It includes everything from vegetables and seafood to chemical elements and construction materials.
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The chapters in the first section — or movement — are named for chemical elements.
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The list includes everything from vegetables and seafood to chemical elements and construction materials.
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Contrary to their name, the 17 rare earth chemical elements are actually quite common.
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The leftmost column contains hydrogen, lithium, sodium, potassium, and other very reactive chemical elements.
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The Eightfold Way is to elementary particles what the Periodic Table is to chemical elements.
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Astronomers use spectra to identify the chemical elements and molecules present on celestial bodies like stars and planets.
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Devised by Russian chemist Dmitri Mendeleev in 1869, the table categorizes chemical elements according to their atomic number.
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Basalt samples reveal their sources through their chemical elements, which link back to the geology of the site.
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For life to arise, Europa needs two other ingredients: a few essential chemical elements, and a source of energy.
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My original submission used that phrase as the revealer, thereby giving a raison d'être for abbreviating the chemical elements.
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As for Europa, scientists think it first formed with the necessary chemical elements: carbon, hydrogen, nitrogen, oxygen, phosphorus and sulfur.
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The researchers' interest was in the isotopic ratios, in the teeth under investigation, of two chemical elements: oxygen and strontium.
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Rare earths are a group of 17 chemical elements used in products ranging from high-tech consumer electronics to military equipment.
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The chemical elements in these basalt samples were then compared to materials found within several other major quarries on the island.
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These rods are made of chemical elements like boron that can absorb neutrons without getting caught up in the fissioning process.
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To do so, the researchers had to map the chemical elements associated with the pigment melanin—the dominant pigment in animals.
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The chemical elements on the periodic table with atomic numbers 28503 through 22019 make up the critical elements called rare earths.
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The mine was once among the world's largest for rare earths, which are chemical elements used in cell phones and military equipment.
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As its skies are backlit by the star, astronomers can sometimes detect chemical elements in its atmosphere by studying the filtered light.
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But, apart from being fun study tools, this year we have even more reason to sing songs that celebrate the chemical elements.
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China produced 80% of rare-earths, a group of 17 chemical elements used in electronics, imported by the United States in 2017.
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We're also entering into a new era in which scientists can discern the chemical elements found in the atmospheres of these distant worlds.
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In particular, neutron-star mergers are thought to be an important source of the heaviest chemical elements, such as gold, platinum and uranium.
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They have documented landslides near exploration activity, as well as dangerous levels of chemical elements like arsenic, manganese, copper and molybdenum in water sources.
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Dmitri Mendeleev's world-changing system turns 150 in 2019, and the United Nations has designated it the Year of the Periodic Table of Chemical Elements.
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The ministry on Monday also approved several vehicles that use "ternary" lithium-ion batteries, which employ the chemical elements of nickel, cobalt and manganese (NCM).
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Krasznahorkay's team first developed the X17 hypothesis years ago, after conducting an experiment that involved shooting protons at isotopes, which are variants of chemical elements.
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These two-letter answers are the names of chemical elements, and Mr. Eaton-Salners has placed them in slots that match their ATOMIC NUMBERS (34A).
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Precious gems are born of strife, of shotgun marriages between hostile chemical elements, and they're tough enough to survive cataclysms that obliterate everything around them.
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More than 150 years ago, Lord Kelvin—working with fellow Scottish scholar Peter Guthrie Tait—proposed that the chemical elements could be represented by different knots.
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Though previous studies using isotopes (chemical elements) suggested life on Earth dates back 3.8 billion years, this is the first time that physical evidence supports these findings.
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The presence of these chemical elements points to potential risk—radioactive strontium, for instance, can remain in the body for years and cause bone cancer or leukaemia.
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If Europa's ocean also has a source of energy—think hydrothermal vents—and a few choice chemical elements, there's a decent chance it could support basic lifeforms.
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The last time I studied the periodic table was high school chemistry, and since then, more elements have been added to the iconic, colored chart of chemical elements.
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What I found particularly interesting was that some of the chemical elements in this puzzle had appeared before 1993, mostly in the 1940s, when Margaret Farrar was editor.
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Exports of the group of 17 chemical elements used in consumer electronics and military equipment came in at 5,4763 tonnes last month, according to General Administration of Customs data.
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Exports of the group of 17 chemical elements used in consumer electronics and military equipment came in at 5,243 tonnes last month, according to General Administration of Customs data.
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Michael Thron is part of a four-man crew manning a specially-modified Stryker armored vehicle, which can detect chemical elements up to two miles or three kilometers away.
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"When it comes to light chemical elements (such as carbon and oxygen), these are heavily altered but for heavier elements such as strontium no alteration was observed," Snoeck said.
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The Rosalind Franklin rover's instrument could help identify carbon and sulfur isotopes, atoms representative of chemical elements but different in mass because they contain a different amount of neutrons.
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As scientists celebrated Dmitri Mendeleev's enduring array of chemical elements this year, some also wondered whether there might be a better way to organize the stuff of the universe.
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"People who want to recover their health will not come to a place where there are industries with heavy chemical elements involved," said Tigran Margaryan, a Jermuk hotel owner.
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This technique is used to investigate the chemical elements of ancient pottery and old paintings, and it works by using X-rays to reveal the chemical spectrum of a material.
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Scientists would come to understand that the gaps in a spectrum are due to the absorption of light by the atoms of chemical elements that compose a star's outer layers.
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Rare earths are a group of 0003 chemical elements used in both consumer products, from iPhones to electric car motors, and critical military applications including jet engines, satellites and lasers.
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"We produce different colors by using the fact that different chemical elements heated to high temperatures get rid of their energy by emitting very specific wavelengths of light," Conkling explains.
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China accounted for 80% of rare earths, a group of 17 chemical elements used in high-technology consumer electronics and military equipment, imported by the United States from 2014 to 2017.
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China accounted for 80% of the rare earths, a group of 17 chemical elements used in high-technology consumer electronics and military equipment, imported by the U.S. from 10 to 2017.
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While the laser is firing, spectrometers inside ChemCam record the color wavelengths produced and beams that data back to Earth, where scientists are able to identify what chemical elements are present.
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China accounted for 80% of the rare earths, a group of 17 chemical elements used in high-technology consumer electronics and military equipment, imported by the United States from 2014 to 2017.
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Her process is described as harnessing the chemical elements of her work to bring across industrialist concepts, while juxtaposing the mystery hiding underneath the water with the greater flora of the park.
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Monica Tromp, a microscopist at the Max Planck Institute for the Science of Human History, used scanning electron microscopy to show that the pigment had all the chemical elements of lapis lazuli.
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Rare earths are a group of 17 chemical elements used in a wide range of consumer products from iPhones to electric car motors, and critical military applications including jet engines, satellites and lasers.
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In this case, the researchers were hoping to use micro-XRF analysis to discern the chemical elements of the ink under the paint, and to see if they could make out individual letters.
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Exports of the group of 17 chemical elements used in everything from high-tech consumer electronics to military equipment came in at 3,966 tonnes last month, according to General Administration of Customs data.
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China is ready to use rare earths, a group of 2100 chemical elements used in everything from high-tech consumer electronics to military equipment, to strike back at the United States, Chinese newspapers warned.
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Beijing is ready to use rare earths, a group of 17 chemical elements used in everything from high-tech consumer electronics to military equipment, to strike back at the United States, Chinese newspapers warned.
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His famous admirers included Issac Asimov, a science-fiction writer, and a taste for the nerdy was always a hallmark: one popular song was a jauntily rhyming recitation of all of the chemical elements.
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Since the urine was not diluted by other sewage or rainwater, it could be broken down to its chemical elements, which were then compared against a vast database of substances with known psychoactive effects.
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Rare earths are a group of 17 chemical elements used in everything from high-tech consumer electronics to military equipment and Chinese production accounted for 80% of U.S. imports of the substances between 2014 and 2017.
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The chemical elements are available throughout the world, and are key to everyday tech gadgets and growing innovations, such as smartphones, high definition TVs, hybrid cars, missiles — even the extraction of natural gas known as fracking.
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Mr. MacLachlan connects five of the noble gases on the periodic table of chemical elements with their clue numbers: Helium, for example, which is number 2 on the periodic table, is in the grid at 2D.
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China is ready to use rare earths, a group of 21.5 chemical elements used in everything from high-tech consumer electronics to military equipment, to strike back in a trade war with the United States, Chinese newspapers warned.
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China is the world's dominant producer of rare earths, a group of 17 chemical elements used in a wide range of consumer electronics, and is considering restricting supply in its long-running trade war with the United States.
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HONG KONG (Reuters) - China will consider strengthening controls on exports of rare earths, 17 chemical elements used in high-tech consumer electronics and military equipment, to protect and better use such "strategic resource", the state planner said on Tuesday.
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Exports by China, the key supplier of a group of 17 chemical elements used in everything from high-tech consumer electronics to military equipment, swing sharply from month to month, often by 20 percent or more, customs data shows.
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" Reed was one of the country's only dealers at the time who owned an X-ray fluorescence analyzer (XRF), a $40,000 device that looks like a raygun and can identify the chemical elements in a geologic sample within seconds. "Mr.
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The researchers are also excited to have PIXL onboard, an X-ray fluorescence spectrometer with high-resolution capabilities to map the elements in the Martian soil with greater detail and the best detection and analysis of chemical elements so far.
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HONG KONG/BEIJING (Reuters) - Beijing is "seriously considering" restricting exports to the United States of rare earths, 17 chemical elements used in high-tech consumer electronics and military equipment, the editor in chief of China's Global Times said on Tuesday.
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Chinese state-owned newspapers warned this week that Beijing was ready to use its dominance in the production of rare earths - chemical elements used in everything from high-tech consumer electronics to military equipment - in its trade war with the United States.
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Xi's visit stoked fears China would use its dominance over production of rare earths, a group of 17 chemical elements prized for their use in consumer electronics and military equipment, in the escalating trade war, although no restrictions on supplies have so far been announced.
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In one of the latest potential developments, the editor in chief of China's Global Times said on Tuesday that Beijing was "seriously considering" restricting exports to the United States of rare earths, 21 chemical elements used in high-tech consumer electronics and military equipment.
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Safe haven assets rallied strongly in early trade with Germany's 3.1753-year government bond and 10-year US Treasuries falling after reports that China is ready to hit back against the United States with tariffs on rare earths — a group of 17 chemical elements used in everything from high-tech consumer electronics to military equipment.
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In reality, any extraterrestrial receiving the message would be hard-pressed to understand that this low-resolution bitmap has anything to do with chemistry, and if they did understand every part of the message as it was intended, they would only have the most basic description of the chemical elements in human genetic material—how many atoms of hydrogen, carbon, oxygen, nitrogen, and phosphorus there are in the different sections of DNA.
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But Lavoisier's laboratory is as good a place as any to begin, for it was Lavoisier who published the first putatively comprehensive list of chemical elements—substances incapable of being broken down by chemical reactions into other substances—and it was Lavoisier and his wife Marie-Anne who pioneered the technique of measuring quantitatively what went into and came out of a chemical reaction, as a way of getting to the heart of what such a reaction really is.
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The chemical elements of the periodic table have received various names throughout history. This article lists the etymology of chemical elements of the periodic table.
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Chemical elements' symbols in the staircase The symbols of chemical elements are evenly spaced along the top edge of the facade in the side wings of the Chemistry Faculty building. The 24 characters – heavily stylized abbreviations of the symbols of chemical elements – have been divided into 4 groups of 6 symbols each. The non-metals were placed on the west wing, while metals on the east one. The elements are depicted by the symbols used in the late 19th and early 20th century.
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Chemical composition refers to the identity and relative number of the chemical elements that make up any particular compound.
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Neutral atoms of the chemical elements have the same term symbol for each column in the s-block and p-block elements, but may differ in d-block and f-block elements, if the ground state electron configuration changes within a column. Ground state term symbols for chemical elements are given below.
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The various chemical elements are formally identified by their unique atomic numbers, by their accepted names, and by their symbols.
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For pure chemical elements, polymorphism is known as allotropy. For example, diamond, graphite, and fullerenes are different allotropes of carbon.
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The periodic trends in properties of elements Periodic trends are specific patterns in the properties of chemical elements that are revealed in the periodic table of elements. Major periodic trends include electronegativity, ionization energy, electron affinity, atomic radii, ionic radius, metallic character, and chemical reactivity. Periodic trends from the changes in the atomic structure of the chemical elements within their respective periods (horizontal rows) and groups in the periodic table. These laws enable the chemical elements to be organized in the periodic table based on their atomic structures and properties.
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In astrophysics the term "metal" is cast more widely to refer to all chemical elements in a star that are heavier than the lightest two, hydrogen and helium, and not just traditional metals. A star fuses lighter atoms, mostly hydrogen and helium, into heavier atoms over its lifetime. Used in that sense, the metallicity of an astronomical object is the proportion of its matter made up of the heavier chemical elements. Metals, as chemical elements, comprise 25% of the Earth's crust and are present in many aspects of modern life.
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Virtually any chemical may be found in water, but routine testing is commonly limited to a few chemical elements of unique significance.
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The importance of neutron capture to the observed abundance of the chemical elements was first described in 1957 in the B2FH paper.
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Pirkko Eskola is a Finnish physicist. She discovered the chemical elements Rutherfordium and Dubnium whilst working at the Lawrence Berkeley National Laboratory.
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Robert Siegfried. The Discovery of Potassium and Sodium, and the Problem of the Chemical Elements, Isis, Vol. 54, No. 2. (Jun., 1963), p.
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The number of discovered chemical elements is 118. Take the sentence "The number of chemical elements is necessarily greater than 100". Again, there are two interpretations as per the de dicto/de re distinction. According to the de dicto interpretation, even if the inner workings of the atom could differ, the number of elements could not be 100 or less.
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In particular, his group work on how transport of chemical elements across cell membranes in plants is integrated with cellular signalling and nutritional status.
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The spallation reaction requires a high Z material, chemical elements with a high atomic number (Z) of protons in the nucleus, as a target.
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It was subsequently placed as a noble gas in the middle of several spiral representations of the periodic system for classifying the chemical elements.
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Carbon dioxide Triatomic molecules are molecules composed of three atoms, of either the same or different chemical elements. Examples include H2O, CO2 (pictured) and HCN.
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WorldCat Identities. Retrieved on July 6, 2017. The Behavior of Chemical Elements in Stars (1995), and Spectroscopic Atlas for the Southern Sky Stars and other books.
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During the Scientific Revolution, the ancient theory of classical elements was found to be incorrect, and was replaced by the empirically tested concept of chemical elements.
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The fields of work were hydrides of the chemical elements beryllium, magnesium, boron, aluminium and other metals as well as phosphorus, boron, silicon and boron nitrogen compounds.
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According to IUPAC, chemical elements are not proper nouns in English; consequently, the full name of an element is not routinely capitalized in English, even if derived from a proper noun, as in californium and einsteinium. Isotope names of chemical elements are also uncapitalized if written out, e.g., carbon-12 or uranium-235. Chemical element symbols (such as Cf for californium and Es for einsteinium), are always capitalized (see below).
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Estimated distribution of dark matter and dark energy in the universe. Only the fraction of the mass and energy in the universe labeled "atoms" is composed of chemical elements. Only about 4% of the total mass of the universe is made of atoms or ions, and thus represented by chemical elements. This fraction is about 15% of the total matter, with the remainder of the matter (85%) being dark matter.
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EuChemS Periodic Table depicting elements scarcity In light of the UN declared International Year of the Periodic Table of Chemical Elements of 2019, EuChemS published a Periodic Table which depicts the issue of the abundance of the chemical elements to raise awareness of the need to develop better recycling capacities, to manage waste, and to find alternative materials to the elements that are at risk of being unusable.
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Structures and energies of included chemical elements and compounds are rigorously validated and property predictions are up to a factor of 100 more accurate relative to earlier models.
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Gustavus Detlef Hinrichs (2 December 1836 – 14 February 1923) was a chemist and natural philosopher most widely known for his findings on periodic laws within the chemical elements.
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Dietary supplements can be formulated to contain several different chemical elements (as compounds), a combination of vitamins and/or other chemical compounds, or a single element (as a compound or mixture of compounds), such as calcium (calcium carbonate, calcium citrate) or magnesium (magnesium oxide), or iron (ferrous sulfate, iron bis-glycinate). The dietary focus on chemical elements derives from an interest in supporting the biochemical reactions of metabolism with the required elemental components. Appropriate intake levels of certain chemical elements have been demonstrated to be required to maintain optimal health. Diet can meet all the body's chemical element requirements, although supplements can be used when some recommendations are not adequately met by the diet.
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Upward Movement of Salt in the Plant. With T. C. Broyer and P. R. Stout. Nature, 146 :340-340. Minute Amounts of Chemical Elements in Relation to Plant Growth.
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The iron peak is a local maximum in the vicinity of Fe (Cr, Mn, Fe, Co and Ni) on the graph of the abundances of the chemical elements. For elements lighter than iron on the periodic table, nuclear fusion releases energy. For iron, and for all of the heavier elements, nuclear fusion consumes energy. Chemical elements up to the iron peak are produced in ordinary stellar nucleosynthesis, with the alpha elements being particularly abundant.
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Nuclides such as 92Nb that were present in the primordial solar nebula but have long since decayed away completely are termed extinct radionuclides if they have no other means of being regenerated. Because primordial chemical elements often consist of more than one primordial isotope, there are only 83 distinct primordial chemical elements. Of these, 80 have at least one observationally stable isotope and three additional primordial elements have only radioactive isotopes (bismuth, thorium, and uranium).
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Nuclear reaction analysis (NRA) is a nuclear method of nuclear spectroscopy in materials science to obtain concentration vs. depth distributions for certain target chemical elements in a solid thin film.
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The residence time of a molecule in the first shell varies among the chemical elements from about 100 picoseconds to more than 200 years. Aqua ions are prominent in electrochemistry.
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Nizhniye Sergi, with its Lake Montayevo health resort, is a popular destination in the Ural region. The health resort is known for its mineral water that includes thirty-seven chemical elements.
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The relative atomic diameters of carbon, hydrogen, nitrogen, oxygen, phosphorus, and sulfur CHON is a mnemonic acronym for the four most common elements in living organisms: carbon, hydrogen, oxygen, and nitrogen. The acronym CHNOPS, which stands for carbon, hydrogen, nitrogen, oxygen, phosphorus, sulfur, represents the six most important chemical elements whose covalent combinations make up most biological molecules on Earth.The acronym "S.P. Cohn" was also used in high school biology classes to represent the six chemical elements.
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Neutron capture is involved in the formation of isotopes of chemical elements. As a consequence of this fact the energy of neutron capture intervenes in the standard enthalpy of formation of isotopes.
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While different chemical elements can be purified through chemical processes, isotopes of the same element have nearly identical chemical properties, which makes this type of separation impractical, except for separation of deuterium.
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Ten chemical elements including sodium were discovered there; the electric generator was devised at the Institution, and much of the early work on the atomic structure of crystals was carried out within it.
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A complete set of periodic table elements An assortment of precious metals Hafnium samples for collectors Element collecting is the hobby of collecting the chemical elements. Many element collectors simply enjoy finding peculiar uses of chemical elements. Others enjoy studying the properties of the elements, possibly engaging in amateur chemistry, and some simply collect elements for no practical reason. Some element collectors invest in elements, while some amateur chemists have amassed a large collection of elements—Oliver Sacks, for example.
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Ecological systems (ecosystems) have many biogeochemical cycles operating as a part of the system, for example, the water cycle, the carbon cycle, the nitrogen cycle, etc. All chemical elements occurring in organisms are part of biogeochemical cycles. In addition to being a part of living organisms, these chemical elements also cycle through abiotic factors of ecosystems such as water (hydrosphere), land (lithosphere), and/or the air (atmosphere). The living factors of the planet can be referred to collectively as the biosphere.
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Dmitri Mendeleev, responsible for organizing the known chemical elements in a periodic table. An important breakthrough in making sense of the list of known chemical elements (as well as in understanding the internal structure of atoms) was Dmitri Mendeleev's development of the first modern periodic table, or the periodic classification of the elements. Mendeleev, a Russian chemist, felt that there was some type of order to the elements and he spent more than thirteen years of his life collecting data and assembling the concept, initially with the idea of resolving some of the disorder in the field for his students. Mendeleev found that, when all the known chemical elements were arranged in order of increasing atomic weight, the resulting table displayed a recurring pattern, or periodicity, of properties within groups of elements.
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During his years at Berkeley, he worked with Albert Ghiorso, the discoverer of 12 transuranic chemical elements. He is currently (2013) writing a scientific biography: Element: The Amazing Life and Work of Albert Ghiorso.
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The spectrum of the stars shows that their atmosphere is overabundant in the chemical elements yttrium, barium, and lanthanum. The primary additionally shows an overabundance of zirconium and the secondary is overabundant in sulphur.
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Aside from representing the bottom few levels of a food chain that supports commercially important fisheries, plankton ecosystems play a role in the biogeochemical cycles of many important chemical elements, including the ocean's carbon cycle.
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2019 was designated as International Year of the Periodic Table of Chemical Elements by the United Nations General Assembly given that it coincides with the 150th anniversary of its creation by Dmitri Mendeleev in 1869.
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Is the classification of the chemical elements which is in particular associated with Dmitri Mendeleev (cf., History of the periodic table). Hubert Feger (2001, 1967–1968;Feger, Hubert. 2001. Classification: Conceptions in the social sciences.
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The inorganic chemistry section contains detailed specifics on chemical elements and chemical compounds. It covers various elements and compounds of acids (e.g. sulfuric acid, hydrochloric acid), light metals (e.g. sodium, potassium) and heavy metals (e.g.
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Chemical elements can be detected in astronomical objects by emission lines and absorption lines. The shifting of spectral lines can be used to measure the Doppler shift (red shift or blue shift) of distant objects.
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Determination of the cosmic abundance of elements has a history dating back to early spectroscopic measurements of light from astronomical objects and the identification of emission and absorption lines which corresponded to particular electronic transitions in chemical elements identified on Earth. For example, the element Helium was first identified through its spectroscopic signature in the Sun before it was isolated as a gas on Earth.The Encyclopedia of the Chemical Elements, page 256Oxford English Dictionary (1989), s.v. "helium". Retrieved December 16, 2006, from Oxford English Dictionary Online.
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In Earth science, a geochemical cycle is the pathway that chemical elements take in the surface and crust of the Earth. The term "geochemical" tells us that geological and chemical factors are all included. The migration of heated and compressed chemical elements and compounds such as silicon, aluminium, and general alkali metals through the means of subduction and volcanism is known in the geological world as geochemical cycles. The geochemical cycle encompasses the natural separation and concentration of elements and heat- assisted recombination processes.
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Group 9 is a group (column) of chemical elements in the periodic table. Members are cobalt (Co), rhodium (Rh), iridium (Ir) and meitnerium (Mt).Leigh, G. J. Nomenclature of Inorganic Chemistry: Recommendations 1990. Blackwell Science, 1990. .
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Her hypothetical donation to this imaginary museum was a set of samples of the four most recently discovered chemical elements: nihonium, moscovium, tennessine, and oganesson. She sometimes collaborates with her sister Kat Arney, a science communicator.
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Mercury sulfide, mercuric sulfide, mercury sulphide, or mercury(II) sulfide is a chemical compound composed of the chemical elements mercury and sulfur. It is represented by the chemical formula HgS. It is virtually insoluble in water.
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Honey Lemon wears bright pink armor that was built by Hiro with a mechanical purse that can mix different chemical elements, allowing her to create balls that she can use as explosives, traps, or safe exits.
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Jasminka, A., & Robert, S. (2011). Distribution of chemical elements in an old metallurgical area, Zenica. Geoderma, 71–85. As a result, environmental agencies are placed in charge in remediating, monitoring, and mitigating the soil contamination sites.
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Risk list 2011. A new supply risk index for chemical elements or element groups which are of economic value. Minerals UK In 2010, a solar energy conversion efficiency of about 10% was achieved in a CZTS device.
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Group 8 is a group (column) of chemical elements in the periodic table. It consists of iron (Fe), ruthenium (Ru), osmium (Os) and hassium (Hs).Leigh, G. J. Nomenclature of Inorganic Chemistry: Recommendations 1990. Blackwell Science, 1990. .
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The transuranium elements (also known as transuranic elements) are the chemical elements with atomic numbers greater than 92, which is the atomic number of uranium. All of these elements are unstable and decay radioactively into other elements.
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John Dalton was an English chemist who developed the idea of atomic theory of chemical elements. Dalton's atomic theory of chemical elements assumed that each element had unique atoms associated with and specific to that atom. This was in opposition to Lavoisier's definition of elements which was that elements are substances that chemists could not break down further into simpler parts. Dalton's idea also differed from the idea of corpuscular theory of matter, which believed that all atoms were the same, and had been a supported theory since the 17th century.
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The nature of dark matter is unknown, but it is not composed of atoms of chemical elements because it contains no protons, neutrons, or electrons. (The remaining non-matter part of the mass of the universe is composed of the even more mysterious dark energy). The universe's 94 naturally occurring chemical elements are thought to have been produced by at least four cosmic processes. Most of the hydrogen, helium and a very small quantity of lithium in the universe was produced primordially in the first few minutes of the Big Bang.
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New characters can in principle be coined at any time, just as new words can be, but they may not be adopted. Significant historically recent coinages date to scientific terms of the 19th century. Specifically, Chinese coined new characters for chemical elements – see chemical elements in East Asian languages – which continue to be used and taught in schools in China and Taiwan. In Japan, in the Meiji era (specifically, late 19th century), new characters were coined for some (but not all) SI units, such as ( "meter" + "thousand, kilo-") for kilometer.
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The Oddo–Harkins rule holds that an element with an even atomic number (such as carbon: element 6) is more abundant than both elements with the adjacently larger and smaller odd atomic numbers (such as boron: element 5 and nitrogen: element 7, respectively, for carbon). This tendency of the abundance of the chemical elements was first reported by Giuseppe Oddo in 1914 and William Draper Harkins in 1917. Estimated abundances of the chemical elements in the solar system. Hydrogen and helium, atomic numbers are 1 and 2, respectively, are most abundant, from the Big Bang.
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This work identified chemical elements as a specific type of atom, therefore rejecting Newton's theory of chemical affinities. Instead, Dalton inferred proportions of elements in compounds by taking ratios of the weights of reactants, setting the atomic weight of hydrogen to be identically one. Following Jeremias Benjamin Richter (known for introducing the term stoichiometry), he proposed that chemical elements combine in integral ratios. This is known as the law of multiple proportions or Dalton's law, and Dalton included a clear description of the law in his New System of Chemical Philosophy.
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The periodic table of the chemical elements "The Elements" is a song by musical humorist and lecturer Tom Lehrer, which recites the names of all the chemical elements known at the time of writing, up to number 102, nobelium. It was written in 1959 and can be found on his albums Tom Lehrer in Concert, More of Tom Lehrer and An Evening Wasted with Tom Lehrer. The song is sung to the tune of the "Major-General's Song" from The Pirates of Penzance by Gilbert and Sullivan.Shepherd, Marc.
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Many countries have standardized the labeling of fertilizers to indicate their contents of major nutrients. The most common labeling convention, the NPK or N-P-K label, shows the amounts of the chemical elements nitrogen, phosphorus, and potassium.
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Element Lad (Jan Arrah) is a fictional character in the 30th and 31st centuries of the , a member of the Legion of Super-Heroes. A native of the planet Trom, he has the power to transmute chemical elements.
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Charles Janet in around 1925 Charles Janet (; 15 June 1849 – 7 February 1932) was a French engineer, company director, inventor and biologist. He is also known for his innovative left-step presentation of the periodic table of chemical elements.
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The standard presentation of the chemical elements is in the periodic table, which orders elements by atomic number. The periodic table is arranged in groups, or columns, and periods, or rows. The periodic table is useful in identifying periodic trends.
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Albert Ghiorso (July 15, 1915 – December 26, 2010) was an American nuclear scientist and co-discoverer of a record 12 chemical elements on the periodic table. His research career spanned six decades, from the early 1940s to the late 1990s.
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Theodor Benfey's periodic table (1964) Alternative periodic tables are tabulations of chemical elements differing in their organization from the traditional depiction of the periodic system.E. R. Scerri. The Periodic Table, Its Story and Its Significance. Oxford University Press, New York, 2006, .
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Henry Bent. New Ideas in Chemistry from Fresh Energy for the Periodic Law. AuthorHouse, 2006, . Over a thousand have been devised, often for didactic reasons, as not all correlations between the chemical elements are effectively captured by the standard periodic table.
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The periodic table of the chemical elements In chemistry, an element is a pure substance which cannot be broken down by chemical means, consisting of atoms which have identical numbers of protons in their atomic nuclei. The number of protons in the nucleus is the defining property of an element, and is referred to as the atomic number (represented by the symbol Z). Chemical elements constitute all of the baryonic matter of the universe. In total, 118 elements have been identified. The first 94 occur naturally on Earth, and the remaining 24 are synthetic elements produced in nuclear reactions.
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A period 1 element is one of the chemical elements in the first row (or period) of the periodic table of the chemical elements. The periodic table is laid out in rows to illustrate periodic (recurring) trends in the chemical behaviour of the elements as their atomic number increases: a new row is begun when chemical behaviour begins to repeat, meaning that analog elements fall into the same vertical columns. The first period contains fewer elements than any other row in the table, with only two: hydrogen and helium. This situation can be explained by modern theories of atomic structure.
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Kirchhoff deduced that the dark lines in the solar spectrum are caused by absorption by chemical elements in the Solar atmosphere. In this way it was proved that the chemical elements found in the Sun and stars were also found on Earth. Among those who extended the study of solar and stellar spectra was Norman Lockyer, who in 1868 detected radiant, as well as dark, lines in solar spectra. Working with chemist Edward Frankland to investigate the spectra of elements at various temperatures and pressures, he could not associate a yellow line in the solar spectrum with any known elements.
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Vitalism was a widespread conception that substances found in organic nature are created from the chemical elements by the action of a "vital force" or "life-force" (vis vitalis) that only living organisms possess. Vitalism taught that these "organic" compounds were fundamentally different from the "inorganic" compounds that could be obtained from the elements by chemical manipulations. Vitalism survived for a while even after the rise of modern ideas about the atomic theory and chemical elements. It first came under question in 1824, when Friedrich Wöhler synthesized oxalic acid, a compound known to occur only in living organisms, from cyanogen.
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The only difference is that instead of the subscript number used today (e.g., H2O), Berzelius used a superscript (H2O). Berzelius is credited with identifying the chemical elements silicon, selenium, thorium, and cerium. Students working in Berzelius's laboratory also discovered lithium and vanadium.
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Helium was first detected on Earth in 1882,Alfred Walter Stewart, Recent Advances in Physical and Inorganic Chemistry, p. 201, BiblioBazaar, 2008 . but not isolated until 1895,Clifford A. Hampel, The Encyclopedia of the Chemical Elements, Van Nostrand Reinhold, pp. 256–268, 1968 .
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Charlotte Emma Moore Sitterly (September 24, 1898 – March 3, 1990) was an American astronomer. She is known for her extensive spectroscopic studies of the Sun and chemical elements. Her tables of data are known for their reliability and are still used regularly.
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A modern conceptualization of molecules began to develop in the 19th century along with experimental evidence for pure chemical elements and how individual atoms of different chemical substances such as hydrogen and oxygen can combine to form chemically stable molecules such as water molecules.
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Solar Foods Ltd. manufactures Solein, single cell protein. Solein is vegan, and the finished product contains approximately 65 percent protein, 20–25 percent carbohydrates and 5–10 percent fats. Solein also contains small amounts of essential chemical elements, such as nitrogen, phosphorus and potassium.
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Photomicrograph of insect wings by Talbot using a solar microscope Talbot was one of the earliest researchers into the field of spectral analysis. He showed that the spectrum of each of the chemical elements was unique and that it was possible to identify the chemical elements from their spectra. Such analysis was to become important in examining the light from distant stars, and hence inferring their atomic composition. He also investigated the polarization of light using tourmaline crystals and iceland spar or calcite crystals, and pioneered the design and use of the polarizing microscope, now widely used by geologists for examining thin rock sections to identify minerals within them.
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A period 2 element is one of the chemical elements in the second row (or period) of the periodic table of the chemical elements. The periodic table is laid out in rows to illustrate/display recurring (periodic) trends in the chemical behavior of the elements as their atomic number increases; a new row is started when chemical behavior begins to repeat, creating columns of elements with similar properties. The second period contains the elements lithium, beryllium, boron, carbon, nitrogen, oxygen, fluorine, and neon. In a quantum mechanical description of atomic structure, this period corresponds to the filling of the second () shell, more specifically its 2s and 2p subshells.
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Prior to the publication of the B2FH paper, George Gamow advocated a theory of the Universe in which almost all chemical elements, or equivalently atomic nuclei, were synthesized during the Big Bang. Gamow's theory (which differs from present-day Big Bang nucleosynthesis theory) would imply that the abundance of the chemical elements would remain mostly static over time. Hans Bethe and Charles L. Critchfield had shown that the conversion of hydrogen into helium by nuclear fusion could provide the energy required to power stars, by deriving the Proton proton chain (pp-chain) in 1938. Carl von Weizsäcker and Hans Bethe had independently derived the CNO cycle in 1938 and 1939, respectively.
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Chemical elements listed by ionization energy. Lenntech.com In general, the ionization energy of metals is much lower than the ionization energy of nonmetals, which is why, in general, metals will lose electrons to form positively charged ions and nonmetals will gain electrons to form negatively charged ions.
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Search capacities of crystallographic databases differ widely. Basic functionality comprises search by keywords, physical properties, and chemical elements. Of particular importance is search by compound name and lattice parameters. Very useful are search options that allow the use of wildcard characters and logical connectives in search strings.
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The Encyclopedia of the Chemical Elements. New York: Reinhold Book Corporation. pp. 734. LCCN 68-29938. The usual jewelry-making techniques of rolling and soldering are not practical for titanium, although they can be fabricated by welding in an inert atmosphere using, for example, a laser welder.
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The periodic table of the chemical elements. The columns represent the groups. Groups 1, 2 and 13 to 18 constitute the main group. Sometimes groups 3 and 12, as well as the lanthanides and actinides (the two rows at the bottom), are also included in the main group.
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Studies of the "radioactivity", that soon revealed the phenomenon of radioactive decay, provided another argument against considering chemical elements as fundamental nature's elements. Despite these discoveries, the term atom stuck to Dalton's (chemical) atoms and now denotes the smallest particle of a chemical element, not something really indivisible.
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Stibiopalladinite is a mineral containing the chemical elements palladium and antimony. Its chemical formula is Pd5Sb2. It is a silvery white to steel grey opaque mineral crystallizing in the hexagonal crystal system. It was first described in 1929 for an occurrence in the Bushveld igneous complex of South Africa.
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GRS instruments supply data on the distribution and abundance of chemical elements, much as the Lunar Prospector mission did on the moon. In this case, the chemical element thorium was mapped, with higher concentrations shown in yellow/orange/red in the left-hand side image shown on the right.
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The light emitted in the kilonova is believed to come from the radioactive decay of material ejected in the merger of the two neutron stars. This material may be responsible for the production of many of the chemical elements beyond iron, as opposed to the supernova nucleosynthesis theory.
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Nobel laureate Glenn T. Seaborg (PhD 1937) collaborated with Albert Ghiorso (BS 1913) to discover 12 chemical elements, such as americium, berkelium, and californium. David Bohm (PhD 1943) discovered Bohm Diffusion. Nobel laureate Yuan T. Lee (PhD 1965) developed the crossed molecular beam technique for studying chemical reactions.
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It contains the following chemical elements, in amounts of 100 or more micrograms per liter: lithium, calcium, sulfate, magnesium, potassium, silica, and sodium. The brand is owned by Lithia Spring Water, LLC.; Lithia Spring Water is sold directly from Historic Lithia Springs and shipped only within the United States.
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Once understood, the conservation of mass was of great importance in progressing from alchemy to modern chemistry. Once early chemists realized that chemical substances never disappeared but were only transformed into other substances with the same weight, these scientists could for the first time embark on quantitative studies of the transformations of substances. The idea of mass conservation plus a surmise that certain "elemental substances" also could not be transformed into others by chemical reactions, in turn led to an understanding of chemical elements, as well as the idea that all chemical processes and transformations (such as burning and metabolic reactions) are reactions between invariant amounts or weights of these chemical elements.
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It is still in beta, and a new version is released approximately monthly. The releases follow the sequence of chemical elements from the periodic table. The first public release was named Scandium and the current release is Cobalt.Downloads - qsb-mac - Quick Search Box for the Mac - Google Project Hosting. Code.google.com.
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These phenomena can aid various chemical determinations for the composition of gases lit from behind (absorption spectra) and for glowing gases (emission spectra). Spectroscopy (for example) determines what chemical elements comprise a particular star. Spectroscopy is also used in the determination of the distance of a star, using the red shift.
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Latex being collected from a tapped rubber tree. The chemical elements of which plants are constructed—principally carbon, oxygen, hydrogen, nitrogen, phosphorus, sulfur, etc.—are the same as for all other life forms animals, fungi, bacteria and even viruses. Only the details of the molecules into which they are assembled differs.
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The discovery of the chemical elements and atomic theory began to systematize this science, and researchers developed a fundamental understanding of states of matter, ions, chemical bonds and chemical reactions. The success of this science led to a complementary chemical industry that now plays a significant role in the world economy.
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Stellar molecules are molecules that exist or form in stars. Such formations can take place when the temperature is low enough for molecules to form – typically around 6000 K or cooler. Otherwise the stellar matter is restricted to atoms (chemical elements) in the forms of gas or – at very high temperatures – plasma.
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Berzelius is credited with discovering the chemical elements cerium and selenium and with being the first to isolate silicon and thorium. Berzelius discovered cerium in 1803 and selenium in 1817. Berzelius discovered how to isolate silicon in 1824, and thorium in 1824. Students working in Berzelius's laboratory also discovered lithium, lanthanum, and vanadium.
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Any substance consisting of two or more different types of atoms (chemical elements) in a fixed stoichiometric proportion can be termed a chemical compound; the concept is most readily understood when considering pure chemical substances. It follows from their being composed of fixed proportions of two or more types of atoms that chemical compounds can be converted, via chemical reaction, into compounds or substances each having fewer atoms. The ratio of each element in the compound is expressed in a ratio in its chemical formula. A chemical formula is a way of expressing information about the proportions of atoms that constitute a particular chemical compound, using the standard abbreviations for the chemical elements, and subscripts to indicate the number of atoms involved.
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A period 3 element is one of the chemical elements in the third row (or period) of the periodic table of the chemical elements. The periodic table is laid out in rows to illustrate recurring (periodic) trends in the chemical behaviour of the elements as their atomic number increases: a new row is begun when the periodic table skips a row and a chemical behaviour begins to repeat, meaning that elements with similar behavior fall into the same vertical columns. The third period contains eight elements: sodium, magnesium, aluminium, silicon, phosphorus, sulfur, chlorine, and argon. The first two, sodium and magnesium, are members of the s-block of the periodic table, while the others are members of the p-block.
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A period 7 element is one of the chemical elements in the seventh row (or period) of the periodic table of the chemical elements. The periodic table is laid out in rows to illustrate recurring (periodic) trends in the chemical behaviour of the elements as their atomic number increases: a new row is begun when chemical behaviour begins to repeat, meaning that elements with similar behaviour fall into the same vertical columns. The seventh period contains 32 elements, tied for the most with period 6, beginning with francium and ending with oganesson, the heaviest element currently discovered. As a rule, period 7 elements fill their 7s shells first, then their 5f, 6d, and 7p shells in that order, but there are exceptions, such as uranium.
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In addition, the same atoms may be able to form noncrystalline phases. For example, water can also form amorphous ice, while SiO2 can form both fused silica (an amorphous glass) and quartz (a crystal). Likewise, if a substance can form crystals, it can also form polycrystals. For pure chemical elements, polymorphism is known as allotropy.
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Cleve participated in a Swedish expedition to Spitsbergen in 1898. While on this mission, he discovered a number of species of spumellarians, nassellarians, and phaeodarians. Cleve, in collaboration with Otto Höglund prepared numerous previously-undiscovered salts of yttrium and erbium. The two also did work on the chemistry of the chemical elements thorium and lanthanum.
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The only chemical elements that are stable diatomic homonuclear molecules at STP are hydrogen (H2), nitrogen (N2), oxygen (O2), and two halogens: fluorine (F2) and chlorine (Cl2). When grouped together with the monatomic noble gases - helium (He), neon (Ne), argon (Ar), krypton (Kr), xenon (Xe), and radon (Rn) - these gases are called "elemental gases".
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Spontaneous fission (SF) is a form of radioactive decay that is found only in very heavy chemical elements. The nuclear binding energy of the elements reaches its maximum at an atomic mass number of about 56; spontaneous breakdown into smaller nuclei and a few isolated nuclear particles becomes possible at greater atomic mass numbers.
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Throughout the history of chemistry, several chemical elements have been discovered. In the nineteenth century, Dmitri Mendeleev formulated the periodic table, a table of elements which describes their structure. Because elements have been discovered at various times and places, from antiquity through the present day, their names have derived from several languages and cultures.
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In the periodic table of the elements, each numbered row is a period. A period in the periodic table is a row of chemical elements. All elements in a row have the same number of electron shells. Each next element in a period has one more proton and is less metallic than its predecessor.
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An oxyanion, or oxoanion, is an ion with the generic formula (where A represents a chemical element and O represents an oxygen atom). Oxyanions are formed by a large majority of the chemical elements. The formulae of simple oxyanions are determined by the octet rule. The corresponding oxyacid of an oxyanion is the compound .
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"Element 39: Yttrium". Exploring Chemical Elements and their Compounds. New York: TAB Books. pp. 150–152. . In 1843, Carl Gustaf Mosander found that samples of yttria contained three oxides: white yttrium oxide (yttria), yellow terbium oxide (confusingly, this was called 'erbia' at the time) and rose-colored erbium oxide (called 'terbia' at the time).
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18, no 7, p. 3059 These bond breaks produce paramagnetic sites and the reduction in the number of these sites is always due to additional chemical elements such as hydrogen. Hydrogenated amorphous silicon will later become a basic material for the production of large-area electronic devices such as flat screens or photovoltaic panels.
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Physical changes are changes affecting the form of a chemical substance, but not its chemical composition. Physical changes are used to separate mixtures into their component compounds, but can not usually be used to separate compounds into chemical elements or simpler compounds.Zumdahl, Steven S. and Zumdahl, Susan A. (2000), Chemistry, Houghton Mifflin, 5th ed., p.
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The Distribution of Chemical Elements in Sponges of the Family Lubomirskiidae in Lake Baikal. International Symposium - Speciation in Ancient Lakes, SIAL III - Irkutsk 2002. Berliner Paläobiologische Abhandlungen 4: 151-157. Lubomirskia baikalensis is found on hard bottoms of shallow water at depths between Kaluzhnaya; Belikov; Schröder; Rothenberger; Zapf; Kaandorp; Borejko; Müller; and Müller (2005).
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Joseph von Fraunhofer builds the first accurate spectrometer and uses it to study the spectrum of the Sun's light. He discovers and maps hundreds of fine dark lines crossing the solar spectrum. In 1859 these lines are linked to chemical elements in the Sun's atmosphere. Spectroscopy becomes a method for studying what stars are made of.
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In some pieces, materials have been affixed and then exposed to water or chemical elements, so that their decay is literally imprinted on the surface of the artwork. In 2012 work began on the cover art for the album Hesitation Marks, released in 2013, and subsequently an art book called Cargo in the Blood, released in December 2015.
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This is a list of chemical elements and their atomic properties, ordered by Atomic number. Since valence electrons are not clearly defined for the d-block and f-block elements, there not being a clear point at which further ionisation becomes unprofitable, a purely formal definition as number of electrons in the outermost shell has been used.
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The chalcogens () are the chemical elements in group 16 of the periodic table. This group is also known as the oxygen family. It consists of the elements oxygen (O), sulfur (S), selenium (Se), tellurium (Te), and the radioactive element polonium (Po). The chemically uncharacterized synthetic element livermorium (Lv) is predicted to be a chalcogen as well.
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Cu comes from cuprum, Fe comes from ferrum, Ag from argentum. The symbols were not followed by a period (full stop) as with abbreviations. Later chemical elements were also assigned unique chemical symbols, based on the name of the element, but not necessarily in English. For example, sodium has the chemical symbol 'Na' after the Latin natrium.
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He appeared on Jimmy Kimmel Live! for the third time on April 2, 2014, and showed his interest and knowledge about chemical elements in the periodic table. He appeared on the show again on November 23, 2015, when he won a shut-out victory against the cast of Star Wars: The Force Awakens in a Star Wars trivia contest.
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The neutron activation of the soon-to-be vaporized metal is responsible for a significant portion of the nuclear fallout in nuclear bursts high in the atmosphere. In other types of activation, neutrons may irradiate soil that is dispersed in a mushroom cloud at or near the Earth's surface, resulting in fallout from activation of soil chemical elements.
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A plastic ball-and-stick model of proline. These models usually comply with CPK coloring. In chemistry, the CPK coloring is a popular color convention for distinguishing atoms of different chemical elements in molecular models. The scheme is named after the CPK molecular models designed by chemists Robert Corey and Linus Pauling, and improved by Walter Koltun.
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Aluminium (symbol Al) or aluminum (American English) is a silvery white member of the boron group of chemical elements and a p-block metal classified by some chemists as a post-transition metal.Huheey JE, Keiter EA & Keiter RL 1993, Principles of Structure & Reactivity, 4th ed., HarperCollins College Publishers, , p. 28 It is not soluble in water under normal circumstances.
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SCISAT-1 is a Canadian satellite designed to make observations of the Earth's atmosphere. Its main instruments are an optical Fourier transform infrared spectrometer, the ACE-FTS Instrument, and an ultraviolet spectrophotometer, MAESTRO. These devices record spectra of the Sun, as sunlight passes through the Earth's atmosphere, making analyses of the chemical elements of the atmosphere possible.
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Plant nutrition is the study of the chemical elements that are necessary for plant growth. There are several principles that apply to plant nutrition. Some elements are directly involved in plant metabolism. However, this principle does not account for the so- called beneficial elements, whose presence, while not required, has clear positive effects on plant growth.
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Body composition may be analyzed in various ways. This can be done in terms of the chemical elements present, or by molecular type e.g., water, protein, fats (or lipids), hydroxylapatite (in bones), carbohydrates (such as glycogen and glucose) and DNA. In terms of tissue type, the body may be analyzed into water, fat, connective tissue, muscle, bone, etc.
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Stannoidite is a sulfide mineral composed of five chemical elements: copper, iron, zinc, tin and sulfur. Its name originates from Latin stannum (tin) and Greek eides (or Latin oïda meaning "like"). The mineral is found in hydrothermal Cu-Sn deposits. Stannoidite was first described in 1969 for an occurrence in the Konjo mine, Okayama prefecture, Honshu Island, Japan.
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Willard's research interests focused on analytical chemistry and quantitative analysis of inorganic substances. With student G. Frederick Smith, he was particularly productive in studying perchloric acid and periodic acid salts. In addition, he is credited with important work in determining precise atomic weights of chemical elements such as lithium, silver, and antimony, and with development of metal alloy techniques.
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8 Antoine Lavoisier, in the 18th century, replaced the alchemical theory of elements with the modern theory of chemical elements, and John Dalton further developed the notion of atoms (from the alchemical theory of corpuscles) to explain various chemical processes. The disintegration of atoms is a distinct process involving much greater energies than could be achieved by alchemists.
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This is a list of known oxidation states of the chemical elements, excluding nonintegral values. The most common states appear in bold. The table is based on that of Greenwood and Earnshaw, with additions noted. Every element exists in oxidation state 0 when it is the pure non-ionized element in any phase, whether monatomic or polyatomic allotrope.
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Different isotopes of chemical elements have slightly different chemical behaviors, but for most elements the differences are far too small to have a biological effect. In the case of hydrogen, larger differences in chemical properties among protium (light hydrogen), deuterium, and tritium occur, because chemical bond energy depends on the reduced mass of the nucleus–electron system; this is altered in heavy-hydrogen compounds (hydrogen-deuterium oxide is the most common species) more than for heavy-isotope substitution involving other chemical elements. The isotope effects are especially relevant in biological systems, which are very sensitive to even the smaller changes, due to isotopically-influenced properties of water when it acts as a solvent. Heavy water affects the period of circadian oscillations, consistently increasing the length of each cycle.
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Superheavy elements, also known as transactinide elements, transactinides, or super-heavy elements, are the chemical elements with atomic numbers greater than 103. The superheavy elements are immediately beyond the actinides in the periodic table; the heaviest actinide is lawrencium (atomic number 103). By definition, superheavy elements are also transuranic elements, i.e. having atomic numbers greater than that of uranium (92).
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All life forms require certain core chemical elements needed for biochemical functioning. These include carbon, hydrogen, nitrogen, oxygen, phosphorus, and sulfur—the elemental macronutrients for all organisms—often represented by the acronym CHNOPS. Together these make up nucleic acids, proteins and lipids, the bulk of living matter. Five of these six elements comprise the chemical components of DNA, the exception being sulfur.
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In June 2015, astronomers reported evidence for Population III stars in the Cosmos Redshift 7 galaxy at . Such stars are likely to have existed in the very early universe (i.e., at high redshift), and may have started the production of chemical elements heavier than hydrogen that are needed for the later formation of planets and life as we know it.
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He began measuring the free energy values related to several chemical processes, both organic and inorganic. In 1916, he also proposed his theory of bonding and added information about electrons in the periodic table of the chemical elements. In 1933, he started his research on isotope separation. Lewis worked with hydrogen and managed to purify a sample of heavy water.
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Darkness in an x-ray image corresponds to the amount of matter the x-rays pass through. The density of a neutron image provides information on neutron absorption. Absorption rates vary by many orders of magnitude among the chemical elements. While neutrons have no charge, they do have spin and therefore a magnetic moment that can interact with external magnetic fields.
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Hydrogen is the chemical element with the symbol H and atomic number 1\. With a standard atomic weight of , hydrogen is the lightest element in the periodic table. Hydrogen is the most abundant chemical substance in the universe, constituting roughly 75% of all baryonic mass.However, most of the universe's mass is not in the form of baryons or chemical elements.
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The Periodic Table of Videos (usually shortened to Periodic Videos) is a series of videos about chemical elements and the periodic table. They are published on YouTube and produced by Brady Haran, a former BBC video journalist, featuring Sir Martyn Poliakoff ("The Professor"), Peter Licence, Stephen Liddle, Debbie Kays, Neil Barnes, Sam Tang and others at the University of Nottingham.
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Chemistry as we know it today, was invented by Antoine Lavoisier with his law of conservation of mass in 1783. The discoveries of the chemical elements has a long history culminating in the creation of the periodic table by Dmitri Mendeleev. The Nobel Prize in Chemistry created in 1901 gives an excellent overview of chemical discovery since the start of the 20th century.
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Dmitri Mendeleev From Boyle until the early 20th century, an element was defined as a pure substance that could not be decomposed into any simpler substance. Put another way, a chemical element cannot be transformed into other chemical elements by chemical processes. Elements during this time were generally distinguished by their atomic weights, a property measurable with fair accuracy by available analytical techniques.
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Chaverri Rodríguez created an arrangement of the Periodic Table of Chemical Elements, published in 1952 in the Journal of Chemical Education. His arrangement is based on the electronic structure of the elements, which allows for the placement of the lanthanide and actinide series in a logical sequence according to their atomic number. It has been used for teaching chemistry in Costa Rican schools.
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The lithium nickel cobalt aluminium oxides (NCA) are a group of substances comprising metal oxides. Some of them are important due to their application in lithium ion batteries. NCAs are used as active material on the positive pole (which is the cathode when the battery is discharged). NCAs are mixed oxides comprising the cations of the chemical elements lithium, nickel, cobalt and aluminium.
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The spacecraft had a basic triangular structure of aluminum tubing that provided mounting surfaces for engineering and scientific equipment. The objectives were to obtain postlanding television pictures of the lunar surface, conduct a Vernier engine erosion experiment, determine the relative abundance of the chemical elements in the lunar soil, obtain touchdown dynamics data, and obtain thermal and radar reflectivity data.
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The actinoid (IUPAC nomenclature, also called actinideThe ending -ide normally indicates a negative ion in a binary compound such as chloride, fluoride, nitride, sulfide, etc. therefore actinoid is preferred to actinide. ) series encompasses the 15 metallic chemical elements with atomic numbers from 89 to 103, actinium through lawrencium. The actinoid series derives its name from the first element in the series, actinium.
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Logarithm of the relative energy output (ε) of proton–proton (PP), CNO and Triple-α fusion processes at different temperatures. The dashed line shows the combined energy generation of the PP and CNO processes within a star. At the Sun's core temperature, the PP process is more efficient. Stellar nucleosynthesis is the creation (nucleosynthesis) of chemical elements by nuclear fusion reactions within stars.
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In comparison with the lanthanides, also mostly f-block elements, the actinides show much more variable valence. The actinide series encompasses the 15 metallic chemical elements with atomic numbers from 89 to 103, actinium through lawrencium.Actinide element, Encyclopædia Britannica onlineAlthough "actinoid" (rather than "actinide") means "actinium-like" and therefore should exclude actinium, that element is usually included in the series.
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Hence alumina, magnesia and chromia, are, respectively, Al2O3, MgO and Cr2O3. Special types of oxides are peroxide, O22−, and superoxide, O2−. In such species, oxygen is assigned higher oxidation states than oxide. The chemical formulas of the oxides of the chemical elements in their highest oxidation state are predictable and are derived from the number of valence electrons for that element.
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His doctoral student Marie Curie discovered that only certain chemical elements gave off these rays of energy. She named this behavior radioactivity. Alpha rays (alpha particles) and beta rays (beta particles) were differentiated by Ernest Rutherford through simple experimentation in 1899. Rutherford used a generic pitchblende radioactive source and determined that the rays produced by the source had differing penetrations in materials.
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There are biogeochemical cycles for the chemical elements calcium, carbon, hydrogen, mercury, nitrogen, oxygen, phosphorus, selenium, and sulfur; molecular cycles for water and silica; macroscopic cycles such as the rock cycle; as well as human-induced cycles for synthetic compounds such as polychlorinated biphenyl (PCB). In some cycles there are reservoirs where a substance remains for a long period of time.
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McMillan would found a lab at Berkeley that would be involved in the discovery of many new elements and isotopes. ;1941:Glenn T. Seaborg takes over McMillan's work creating new atomic nuclei. Pioneers method of neutron capture and later through other nuclear reactions. Would become the principal or co- discoverer of nine new chemical elements, and dozens of new isotopes of existing elements.
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The version after that, Juno, has a triple meaning: a Roman mythological figure, an asteroid, and a spacecraft to Jupiter. Kepler, Luna, and Mars continued the astronomy theme, and then Neon and Oxygen constituted a theme of chemical elements. Photon represented a return to sun-themed names. , the alphabetic scheme was abandoned and instead releases are named in the format YYYY-MM.
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Stephen J. Smartt FRS (born 9 November 1968) is an Irish astrophysicist who specializes in stellar evolution, supernovae and time domain sky surveys. He is credited with the discovery of stars that explode as supernovae, measuring their mass, luminosity and the chemical elements synthesized. He is a Professor of Astrophysics at the School of Mathematics and Physics at Queen's University Belfast.
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The building blocks of materials are the chemical elements. These can be identified by their atomic number Z, which is the number of protons in the nucleus. An element can have more than one value for N, the number of neutrons in the nucleus. The sum of these is the mass number, which is roughly equal to the atomic mass.
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The Sun is composed primarily of the chemical elements hydrogen and helium; they account for 74.9% and 23.8% of the mass of the Sun in the photosphere, respectively. All heavier elements, called metals in astronomy, account for less than 2% of the mass, with oxygen (roughly 1% of the Sun's mass), carbon (0.3%), neon (0.2%), and iron (0.2%) being the most abundant.
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This occurs because a large amount of latent heat is liberated as steam condenses into liquid water on the skin. Even though thermal energy is liberated or absorbed during phase transitions, pure chemical elements, compounds, and eutectic alloys exhibit no temperature change whatsoever while they undergo them (see Fig. 7, below right). Consider one particular type of phase transition: melting.
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The abundance of the chemical elements is a measure of the occurrence of the chemical elements relative to all other elements in a given environment. Abundance is measured in one of three ways: by the mass-fraction (the same as weight fraction); by the mole-fraction (fraction of atoms by numerical count, or sometimes fraction of molecules in gases); or by the volume-fraction. Volume-fraction is a common abundance measure in mixed gases such as planetary atmospheres, and is similar in value to molecular mole-fraction for gas mixtures at relatively low densities and pressures, and ideal gas mixtures. Most abundance values in this article are given as mass-fractions. For example, the abundance of oxygen in pure water can be measured in two ways: the mass fraction is about 89%, because that is the fraction of water's mass which is oxygen.
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In the 19th century, Sir William Thomson made a hypothesis that the chemical elements were based upon knotted vortices in the aether. In an attempt to make a periodic table of the elements, P. G. Tait, C. N. Little and others started to attempt to count all possible knots. Because their work predated the invention of the digital computer, all work had to be done by hand.
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289–290 An important class of redox reactions are the electrochemical reactions, where electrons from the power supply are used as the reducing agent. These reactions are particularly important for the production of chemical elements, such as chlorineWiberg, p. 409 or aluminium. The reverse process in which electrons are released in redox reactions and can be used as electrical energy is possible and used in batteries.
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The only chemical elements that are stable single atom molecules at standard temperature and pressure (STP) are the noble gases. These are helium, neon, argon, krypton, xenon, and radon. Noble gases have a full outer valence shell making them rather non-reactive species. While these elements have been described historically as completely inert, chemical compounds have been synthesized with all but neon and helium.
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Group 12, by modern IUPAC numbering, is a group of chemical elements in the periodic table. It includes zinc (Zn), cadmium (Cd) and mercury (Hg). The further inclusion of copernicium (Cn) in group 12 is supported by recent experiments on individual copernicium atoms. Formerly this group was named IIB (pronounced as "group two B", as the "II" is a Roman numeral) by CAS and old IUPAC system.
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Per Teodor Cleve (10 February 1840 – 18 June 1905) was a Swedish chemist, biologist, mineralogist and oceanographer. He is best known for his discovery of the chemical elements holmium and thulium. Born in Stockholm in 1840, Cleve earned his BSc and PhD from Uppsala University in 1863 and 1868, respectively. After receiving his PhD, he became an assistant professor of chemistry at the university.
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Si3N4 ceramic bearing parts Ceramic solids are composed of inorganic compounds, usually oxides of chemical elements. They are chemically inert, and often are capable of withstanding chemical erosion that occurs in an acidic or caustic environment. Ceramics generally can withstand high temperatures ranging from 1000 to 1600 °C (1800 to 3000 °F). Exceptions include non-oxide inorganic materials, such as nitrides, borides and carbides.
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Started in June 2008, Periodic Videos is a series of videos about chemical elements and the periodic table. Working with Professor Martyn Poliakoff, Haran's videos explaining chemistry and science for non-technical persons have received positive recognition. Together, they have made over 500 short videos that cover the elements and other chemistry-related topics. Their YouTube channel has had more than 159 million views.
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Gil Chaverri Rodríguez (March 15, 1921, Heredia, Costa Rica - May 27, 2005 San José, Costa Rica) was a Costa Rican chemist and physicist. Chaverri created an original arrangement of the periodic table of chemical elements, published in 1952 in the Journal of Chemical Education. His arrangement of the periodic table was based on the electronic structure of each element, and was used in Costa Rican schools.
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In addition, different chemical elements, necessary for life, are constantly recycled between the different components. The climate system can change due to internal variability and external forcings. These external forcings can be natural, such as variations in solar intensity and volcanic eruptions, or caused by humans. Accumulation of heat-trapping greenhouse gases, mainly being emitted by people burning fossil fuels, is causing global warming.
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Bird guano has high levels of nutrients like nitrate and ammonium. By mass, it is 8-21% nitrogen; the nitrogen content is about 80% uric acid, 10% protein, 7% ammonia, and 0.5% nitrate. Some of bird guano's most common chemical elements are phosphorus, calcium, and magnesium. It may react with the rocky substrate of islands like basalt to form authigenic, phosphatic minerals including taranakite and leucophosphite.
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A team of researchers at the University of Leicester conducted an analysis of the burst's X-ray afterglow with the XMM-Newton observatory. They found evidence for emission lines of magnesium, silicon, sulphur, and various other chemical elements. This was the first detection of these elements in the spectrum of a GRB. These observations provided strong evidence for a relation between gamma-ray bursts and supernova.
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Julius Lothar Meyer (19 August 1830 – 11 April 1895) was a German chemist. He was one of the pioneers in developing the earliest versions of the periodic table of the chemical elements. Russian chemist Dmitri Mendeleev (his chief rival) and he had both worked with Robert Bunsen. Meyer never used his first given name, and was known throughout his life simply as Lothar Meyer.
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Hydrogen discharge tube Deuterium discharge tube Hydrogen (H) is the chemical element with atomic number 1. At standard temperature and pressure, hydrogen is a colorless, odorless, nonmetallic, tasteless, highly flammable diatomic gas with the molecular formula H2. With an atomic mass of 1.00794 amu, hydrogen is the lightest element. Hydrogen is the most abundant of the chemical elements, constituting roughly 75% of the universe's elemental mass.
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Datasheets and pages are available for specific properties of chemicals in Chemical elements data references: example, Melting points of the elements (data page). Specific materials have technical data in individual sheets such as ethanol: this includes subjects such as structure and properties, thermodynamic properties, spectral data, vapor pressure, etc. Other chemical data sheets are available from individual producers of chemicals, often on their web pages.
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News, Nr. 107, 1913, pp. 97–99 The early researchers also discovered that many other chemical elements, besides uranium, have radioactive isotopes. A systematic search for the total radioactivity in uranium ores also guided Pierre and Marie Curie to isolate two new elements: polonium and radium. Except for the radioactivity of radium, the chemical similarity of radium to barium made these two elements difficult to distinguish.
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Tellurium on quartz (Moctezuma, Sonora, Mexico) Native tellurium crystal on sylvanite (Vatukoula, Viti Levu, Fiji). Picture width 2 mm. With an abundance in the Earth's crust comparable to that of platinum (about 1 µg/kg), tellurium is one of the rarest stable solid elements. In comparison, even the rarest of the stable lanthanides have crustal abundances of 500 µg/kg (see Abundance of the chemical elements).
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Prout's hypothesis was an early 19th-century attempt to explain the properties of the chemical elements using the internal structure of the atom. In 1815, the English chemist William Prout observed that the atomic weights that had been measured were integer multiples of the atomic weight of hydrogen.William Prout (1815). On the relation between the specific gravities of bodies in their gaseous state and the weights of their atoms.
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The most common planetary surface material in the Solar System appears to be water ice. Surface ice is found as close to the Sun as Mercury but is more abundant beyond Mars. Other surfaces include solid matter in combinations of rock, regolith and frozen chemical elements and chemical compounds. In general, ice predominates planetary surfaces beyond the frost line, while closer to the sun, rock and regolith predominate.
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IC 4651 is an open cluster of stars located about 2,900 light years distant in the constellation Ara. It was first catalogued by John Louis Emil Dreyer in his 1895 version of the Index Catalogue. This is an intermediate age cluster that is billion years old. Compared to the Sun, the members of this cluster have a higher abundance of the chemical elements other than hydrogen and helium.
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Gold is a chemical element with the symbol Au (from ) and atomic number 79, making it one of the higher atomic number elements that occur naturally. In a pure form, it is a bright, slightly reddish yellow, dense, soft, malleable, and ductile metal. Chemically, gold is a transition metal and a group 11 element. It is one of the least reactive chemical elements and is solid under standard conditions.
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Despite the low theoretical abundance of lithium, the actual observable amount is less than the calculated amount by a factor of 3-4. This contrasts with the observed abundance of isotopes of hydrogen (1H and 2H) and helium (3He and 4He) that are consistent with predictions. Abundances of the chemical elements in the Solar System. Hydrogen and helium are most common, residuals within the paradigm of the Big Bang.
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The Vogt–Russell theorem states that the structure of a star, in hydrostatic and thermal equilibrium with all energy derived from nuclear reactions, is uniquely determined by its mass and the distribution of chemical elements throughout its interior. Although referred to as a theorem, the Vogt–Russell theorem has never been formally proved. The theorem is named after astronomers Heinrich Vogt and Henry Norris Russell, who devised it independently.
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Theoretical quantum-mechanical calculations become rather accurate to describe the energy structure of some simple electronic configurations. The results of theoretical developments were summarized by Condon and Shortley in 1935. Edlén thoroughly analyzed spectra of MIA for many chemical elements and derived regularities in energy structures of MIA for many isoelectronic sequences (ions with the same number of electrons, but different nuclear charges). Spectra of rather high ionization stages (e.g.
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The IUPAC/IUPAP Joint Working Party is a group convened periodically by the International Union of Pure and Applied Chemistry (IUPAC) and the International Union of Pure and Applied Physics (IUPAP) to consider claims for discovery and naming of new chemical elements. It is sometimes called the Joint Working Party on Discovery of Elements. The working party's recommendations are voted on by the General Assembly of the IUPAP.
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In later life, Urey helped develop the field of cosmochemistry and is credited with coining the term. His work on oxygen-18 led him to develop theories about the abundance of the chemical elements on earth, and of their abundance and evolution in the stars. Urey summarized his work in The Planets: Their Origin and Development (1952). Urey speculated that the early terrestrial atmosphere was composed of ammonia, methane, and hydrogen.
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Fersman wrote more than 1,500 articles and publications on crystallography, mineralogy, geology, chemistry, geochemistry, geography, aerial photography, astronomy, philosophy, art, archeology, soil science, and biology. Among them were: Geochemistry in Russia (1922); Chemical Elements of the Earth and Cosmos (1923); Geochemistry, vols. I–IV (1933–1939); The Search for Mineral Deposits on the Basis of Geochemistry and Mineralogy (1939). He was also a great popularizer of science in Russia.
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This is an important difference from other Reaction Injection Moulding (RIM) systems like polyurethane, since the reaction is not stoichiometric. The 1:1 ratio for DCPD moulding is not critical since this is not a combination of two different chemical elements to form a specific matrix. Significant changes in ratio will slow down the system's reactivity because fewer active reaction nuclei are being formed. This also changes the final properties somewhat.
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Michael Faraday was another early worker, whose major contribution to chemistry was electrochemistry, in which (among other things) a certain quantity of electricity during electrolysis or electrodeposition of metals was shown to be associated with certain quantities of chemical elements, and fixed quantities of the elements therefore with each other, in specific ratios. These findings, like those of Dalton's combining ratios, were early clues to the atomic nature of matter.
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Liquid bronze, being poured into molds during casting. A brass lamp. An alloy is a mixture of chemical elements, which forms an impure substance (admixture) that retains the characteristics of a metal. An alloy is distinct from an impure metal in that, with an alloy, the added elements are well controlled to produce desirable properties, while impure metals such as wrought iron are less controlled, but are often considered useful.
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Structural regularities enable the prediction of as yet unspecified elements, much as occurred with the discovery of the periodic table of chemical elements. Although many parts of the Taxonomy are as yet unformulated, in 2012-2014, Kinston proposed an evolutionary basis for the discovered architecture. In 2007, Kinston introduced THEE by invitation at the Global Organization Design Conference in Toronto, Canada. He then launched the THEE Online Project in 2008.
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The main elements that compose the human body shown from most abundant (by mass) to least abundant. Around two dozen chemical elements are essential to various kinds of biological life. Most rare elements on Earth are not needed by life (exceptions being selenium and iodine), while a few common ones (aluminum and titanium) are not used. Most organisms share element needs, but there are a few differences between plants and animals.
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He was assigned to do ultraviolet spectroscopy of chemical elements. Millikan was persuaded by George Ellery Hale to move to the California Institute of Technology in 1921 and Bowen moved with him. The contact with Hale enabled Bowen also to work at the Mount Wilson Observatory and the Palomar Observatory. Bowen gave lectures on general physics at Caltech and did research on cosmic rays and followed his studies on UV spectroscopy.
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Portable Micro-X-ray fluorescence machine A few minerals are chemical elements, including sulfur, copper, silver, and gold, but the vast majority are compounds. The classical method for identifying composition is wet chemical analysis, which involves dissolving a mineral in an acid such as hydrochloric acid (). The elements in solution are then identified using colorimetry, volumetric analysis or gravimetric analysis. Since 1960, most chemistry analysis is done using instruments.
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Minerals are present in a healthy human being's blood at certain mass and molar concentrations. The figure below presents the concentrations of each of the chemical elements discussed in this article, from center-right to the right. Depending on the concentrations, some are in upper part of the picture, while others are in the lower part. The figure includes the relative values of other constituents of blood such as hormones.
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For comparison, there are about 252 stable nuclides. (In theory, only 146 of them are stable, and the other 106 are believed to decay via alpha decay, beta decay, double beta decay, electron capture, or double electron capture.) All chemical elements can exist as radionuclides. Even the lightest element, hydrogen, has a well-known radionuclide, tritium. Elements heavier than lead, and the elements technetium and promethium, exist only as radionuclides.
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The book describes the internal structure of the atom. The sequence of concepts described in the book follows the sequence that those facts were discovered in. It describes the various sub-atomic structures within the atom, and the functions they fill in the whole structure. Later chapters describe chemical elements and isotopes, the stability and instability of atomic nuclei, and finally atomic energy, the uses it has, and the threat that it poses.
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In 1922 de Hevesy co-discovered (with Dirk Coster) the element hafnium (72Hf) (Latin Hafnia for "Copenhagen", the home town of Niels Bohr). Mendeleev's 1869 periodic table arranged the chemical elements into a logical system, but a chemical element with 72 protons was missing. Hevesy determined to look for that element on the basis of Bohr's atomic model. The mineralogical museum of Norway and Greenland in Copenhagen furnished the material for the research.
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However, it should be easily seen in binoculars or a small telescope. The star is over twice as enriched with chemical elements heavier than hydrogen and helium as the Sun. Because of this and the fact that the star is relatively bright, a group of astronomers in N2K Consortium began to study the star. The star's anomalous composition as measured may be surface pollution only, from the intake of heavy-element planetesimals.
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Chemical similarity (or molecular similarity) refers to the similarity of chemical elements, molecules or chemical compounds with respect to either structural or functional qualities, i.e. the effect that the chemical compound has on reaction partners in inorganic or biological settings. Biological effects and thus also similarity of effects are usually quantified using the biological activity of a compound. In general terms, function can be related to the chemical activity of compounds (among others).
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Both the illumination lens, which is located above the sample and is conventionally called the condenser lens, and the collection lens (called the objective lens) are equipped with fifth-order spherical aberration correctors. The electrons are further energy filtered by a GIF filter and detected by a CCD camera. The filter makes it possible to select electrons scattered by specific chemical elements and so identify individual atoms in the sample being studied.
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Dmitri Mendeleev published a periodic table of the chemical elements in 1869 based on properties that appeared with some regularity as he laid out the elements from lightest to heaviest. When Mendeleev proposed his periodic table, he noted gaps in the table and predicted that then-unknown elements existed with properties appropriate to fill those gaps. He named them eka- boron, eka-aluminium and eka-silicon, with respective atomic masses of 44, 68, and 72.
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As the name implies, coral reefs are made up of coral skeletons from mostly intact coral colonies. As other chemical elements present in corals become incorporated into the calcium carbonate deposits, aragonite is formed. However, shell fragments and the remains of coralline algae such as the green-segmented genus Halimeda can add to the reef's ability to withstand damage from storms and other threats. Such mixtures are visible in structures such as Eniwetok Atoll.
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Gamow, G. (1946, October 1 & 15), Physical Review. Most of the later work in cosmology is founded in Gamow's theory. He applied his model to the question of the creation of the chemical elements for example, Gamow, G. (1942), Jour. Washington Academy of Sciences, Vol. 32 and to the subsequent condensation of matter into galaxies,Gamow, G. (1968) 'On the Origin of Galaxies', Properties of Matter under Unusual Conditions (Edward Teller 60th Birthday Volume).
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In 1934 he was appointed as professor at the University of Oslo. He is well known in the Nordic countries for his textbook Lærebok i organisk kjemi. The first modern Norwegian textbook in organic chemistry, it was first released in 1942 and then re-released several times, the last in 1964. The 1958 edition became known for introducing new Norwegian-language names of several chemical elements: hydrogen, nitrogen, karbon (carbon) og oksygen (oxygen).
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Chemical substances can be simple substances, chemical compounds, or alloys. Chemical elements may or may not be included in the definition, depending on expert viewpoint. Chemical substances are often called 'pure' to set them apart from mixtures. A common example of a chemical substance is pure water; it has the same properties and the same ratio of hydrogen to oxygen whether it is isolated from a river or made in a laboratory.
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Honey Lemon appears as a young American woman in the 2014 Disney animated film Big Hero 6 and television series, voiced by Genesis Rodriguez and in the video game Kingdom Hearts III. She is a quirky chemistry whiz who has a kind heart and tries to find the good in everything. She has a purse that can mix different chemical elements, allowing her to create balls that she uses as explosives or traps.
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Instead, Szilárd proposed using mixtures of lighter known isotopes which produced neutrons in copious amounts. He filed a patent for his idea of a simple nuclear reactor the following year.L. Szilárd, "Improvements in or relating to the transmutation of chemical elements," British patent number: GB630726 (filed: 28 June 1934; published: 30 March 1936). esp@cenet document view In 1936, Szilárd attempted to create a chain reaction using beryllium and indium, but was unsuccessful.
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Individual chemical elements can create more stable electron configurations by combining to share their electrons. It is that sharing of electrons to create stable electronic orbits about the nucleus that appears to us as the chemistry of our macro world. Protons define the entire charge of a nucleus, and hence its chemical identity. Neutrons are electrically neutral, but contribute to the mass of a nucleus to nearly the same extent as the protons.
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Dietary minerals are inorganic chemical elements required by living organisms, other than the four elements carbon, hydrogen, nitrogen, and oxygen that are present in nearly all organic molecules. Some have roles as cofactors, while others are electrolytes. The term "mineral" is archaic, since the intent is to describe simply the less common elements in the diet. Some are heavier than the four just mentioned – including several metals, which often occur as ions in the body.
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Through his use of electric batteries at the Royal Institution Davy first isolated chlorine, followed by the isolation of elemental iodine in 1813. Using the batteries Davy was also able to isolate the elements sodium and potassium. From these experiments Davy concluded that the forces that join chemical elements together must be electrical in nature. Davy was also a proponent against the idea that caloric was an immaterial fluid, arguing instead that heat was a type of motion.
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Cloaca Maxima II (2004) is the second compilation album by the Finnish rock group CMX, released seven years after their first compilation Cloaca Maxima. The name Cloaca Maxima means "Great Sewer" in Latin, and was also the name of the band before it was shortened to CMX. The compilation consists of three CDs named Lyijy, Helium and Uraani respectively. The names of the CDs are all names of chemical elements in Finnish: Lead, Helium and Uranium.
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In survival mode, players need to mine, collect, and refine various chemical elements from asteroids and planets in order to craft tools, weapons, and blocks as well as produce electricity. Resources can be mined manually using a hand drill, or by using ships with the necessary equipment. Components are produced by assembling them from raw materials; however, they can also be harvested by salvaging cargo ships. To avoid death, players must monitor their health, energy and oxygen levels.
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The names for the chemical elements 104 to 106 were the subject of a major controversy starting in the 1960s, described by some nuclear chemists as the Transfermium Wars because it concerned the elements following fermium (element 100) on the periodic table. This controversy arose from disputes between American scientists and Soviet scientists as to which had first isolated these elements. The final resolution of this controversy in 1997 also decided the names of elements 107 to 109.
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Minerals are the exogenous chemical elements indispensable for life. Although the four elements: carbon, hydrogen, oxygen, and nitrogen, are essential for life, they are so plentiful in food and drink that these are not considered nutrients and there are no recommended intakes for these as minerals. The need for nitrogen is addressed by requirements set for protein, which is composed of nitrogen-containing amino acids. Sulfur is essential, but again does not have a recommended intake.
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In the year 2029, chemical elements such as oxygen, carbon, gold, molybdenum, and cobalt were continually disappearing from Earth. These disappearing elements ultimately disrupted the environment and led to the destruction of various homes, cities, and even entire countries. Researchers discovered that the vanishing elements drained into a planet called Nega Earth, located in another dimension. Element dematerialization was occurring rapidly; thus, to save Earth, three special pre-teens picked by the space colony government formed the Element Hunters.
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This oxidation number is found in sulfates, selenates, tellurates, polonates, and their corresponding acids, such as sulfuric acid. Oxygen is the most electronegative element except for fluorine, and forms compounds with almost all of the chemical elements, including some of the noble gases. It commonly bonds with many metals and metalloids to form oxides, including iron oxide, titanium oxide, and silicon oxide. Oxygen's most common oxidation state is −2, and the oxidation state −1 is also relatively common.
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The following outline is provided as an overview of and topical guide to chemistry: Chemistry is the science of atomic matter (matter that is composed of chemical elements), especially its chemical reactions, but also including its properties, structure, composition, behavior, and changes as they relate to the chemical reactions.Chemistry. (n.d.). Merriam-Webster's Medical Dictionary. Retrieved August 19, 2007. Chemistry is centrally concerned with atoms and their interactions with other atoms, and particularly with the properties of chemical bonds.
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Assuming the mass of ordinary matter is about as discussed above, and assuming all atoms are hydrogen atoms (which are about 74% of all atoms in our galaxy by mass, see Abundance of the chemical elements), the estimated total number of atoms in the observable universe is obtained by dividing the mass of ordinary matter by the mass of a hydrogen atom ( divided by ). The result is approximately 1080 hydrogen atoms, also known as the Eddington number.
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The boron group are the chemical elements in group 13 of the periodic table, comprising boron (B), aluminium (Al), gallium (Ga), indium (In), thallium (Tl), and perhaps also the chemically uncharacterized nihonium (Nh). The elements in the boron group are characterized by having three valence electrons. These elements have also been referred to as the triels. Boron is classified as a typical non-metal while the rest, with the possible exception of nihonium, are considered post-transition metals.
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This process was further developed at the Clinton Engineering Works in Oak Ridge, Tennessee, and then entered full-scale production at the Hanford Engineer Works, in Richland, Washington. Seaborg's theoretical development of the actinide concept resulted in a redrawing of the Periodic Table of the Elements into its current configuration with the actinide series appearing below the lanthanide series. Seaborg developed the chemical elements americium and curium while in Chicago. He managed to secure patents for both elements.
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There are also symbols in chemical equations for groups of chemical elements, for example in comparative formulas. These are often a single capital letter, and the letters are reserved and not used for names of specific elements. For example, an "X" indicates a variable group (usually a halogen) in a class of compounds, while "R" is a radical, meaning a compound structure such as a hydrocarbon chain. The letter "Q" is reserved for "heat" in a chemical reaction.
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Knots were studied from a mathematical viewpoint by Carl Friedrich Gauss, who in 1833 developed the Gauss linking integral for computing the linking number of two knots. His student Johann Benedict Listing, after whom Listing's knot is named, furthered their study. In 1867 after observing Scottish physicist Peter Tait's experiments involving smoke rings, Thomson came to the idea that atoms were knots of swirling vortices in the æther. Chemical elements would thus correspond to knots and links.
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The pulsation rate of IK Pegasi A has been measured at 22.9 cycles per day, or once every 0.044 days. Astronomers define the metallicity of a star as the abundance of chemical elements that have a higher atomic number than helium. This is measured by a spectroscopic analysis of the atmosphere, followed by a comparison with the results expected from computed stellar models. In the case of IK Pegasus A, the estimated metal abundance is [M/H] = +0.07 ± 0.20.
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Later, the springs were purchased by the municipality of Salazie, which in turn ceded them to the Colonial administration. However, in 1920 the water temperature dropped and boiling was required to heat it to the accustomated state which in turn destroyed some of the chemical elements. The spa started to lose its attraction. An attempt to clear the springs with dynamite failed disastrously and caused a partial collapse of the spa and the destruction of the casino.
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An 18-column form of the periodic table, positioning Ce−Lu and Th−Lr between groups 3 and 4, in periods 6 and 7. A detailed interactive version is found in below, and an interactive 32-column form, after . The periodic table, also known as the periodic table of elements, is a tabular display of the chemical elements, which are arranged by atomic number, electron configuration, and recurring chemical properties. The structure of the table shows periodic trends.
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He wrote a foreword for Oliver Sacks's 1970 book Migraine. Gooddy delivered in 1976 the Bradshaw Lecture on Time and the nervous system: the neuron as an escapement. Later in his career he became interested in the role of trace elements in the causation of neurological disease, delivering the 8th Gowers Memorial Lecture on chemical elements, neurology, and abiotrophy. Upon his death in 2004 he was survived by his widow, a son, a daughter and three grandchildren.
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In the periodic table of the elements, each numbered column is a group. In chemistry, a group (also known as a family) is a column of elements in the periodic table of the chemical elements. There are 18 numbered groups in the periodic table; the f-block columns (between groups 3 and 4) are not numbered. The elements in a group have similar physical or chemical characteristics of the outermost electron shells of their atoms (i.e.
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The distinction depends on whether heat is going into (melting) or out of (freezing) the sample when the measurement is made. Only gallium is measured while melting; all the other metals are measured while the samples are freezing. A practical effect of ITS-90 is that the triple points and the freezing/melting points of its thirteen chemical elements are precisely known for all temperature measurements calibrated per ITS-90 since these thirteen values are fixed by its definition.
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Soil contamination from heavy elements can be found in the urban environments, which can be attributed to the transportation and industries along with the background levels (minerals- leaching heavy elements from weathering). Also, some of the most soil contaminated areas are around the mines such as the ones in Slovenia, Bosnia and Herzegovina, and in United States (Sulphur Bank Superfund Site, in California).Jasminka, A., & Robert, S. (2011). Distribution of chemical elements in an old metallurgical area, Zenica.
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For 80 of the chemical elements, at least one stable isotope exists. As a rule, there is only a handful of stable isotopes for each of these elements, the average being 3.2 stable isotopes per element. Twenty-six elements have only a single stable isotope, while the largest number of stable isotopes observed for any element is ten, for the element tin. Elements 43, 61, and all elements numbered 83 or higher have no stable isotopes.
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Phlebology, 255: 751- 3. The principles of spectrographic analysis of this test are similar to those used to evaluate the luminescence of captured images by venous translumination, and the histogram also evaluates the scales of red, blue and green (RGB). All organic components are composed of chemical elements that emit light according to their wavelength. This is why the histogram analysis of transluminated images could define an organic element according to the quality and amount of their components.
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In keeping with earlier armchair treasure hunt books, such as Masquerade, the plot bears no relevance to the solution. The answer is instead found in the illustrations and in the squares that border every page. Every page is littered with symbols pointing to the solution including Alchemical symbols, Astrological signs and heraldic cadency symbols. The borders contain objects that make up the solution including Latin names for plants, chemical elements, and symbols indicating direction and movement.
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With their positive charge, the protons within the nucleus are repelled by the long-range electromagnetic force, but the much stronger, but short-range, nuclear force binds the nucleons closely together. Neutrons are required for the stability of nuclei, with the exception of the single-proton hydrogen nucleus. Neutrons are produced copiously in nuclear fission and fusion. They are a primary contributor to the nucleosynthesis of chemical elements within stars through fission, fusion, and neutron capture processes.
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The forces driving biogeochemical cycles include metabolic processes within organisms, geological processes involving the earth's mantle, as well as chemical reactions among the substances themselves, which is why these are called biogeochemical cycles. While chemical substances can be broken down and recombined, the chemical elements themselves can be neither created nor destroyed by these forces, so apart from some losses to and gains from outer space, elements are recycled or stored (sequestered) somewhere on the planet.
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The mineral is called bazirite, named after the chemical elements barium and zirconium. Bazirite has the chemical composition BaZrSi3O9. Rockall forms part of the deeply eroded Rockall Igneous Centre that was formed as part of the North Atlantic Igneous Province, approximately 55 million years ago, when the ancient continent of Laurasia was split apart by plate tectonics. Greenland and Europe separated and the northeast Atlantic Ocean was formed between them, eventually leaving Rockall as an isolated islet.
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The hydrodynamic wind within the upper portion of a planet's atmosphere allows light chemical elements such as Hydrogen to move up to the exobase, the lower limit of the exosphere, where the gases can then reach escape velocity, entering outer space without impacting other particles of gas. This type of gas loss from a planet into space is known as planetary wind. Planets with hot lower atmospheres could result in humid upper atmospheres that accelerate the loss of hydrogen.
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All of the remaining elements in a human body are called "trace elements". The trace elements that have a specific biochemical function in the human body are sulfur, iron, chlorine, cobalt, copper, zinc, manganese, molybdenum, iodine, and selenium. Most chemical elements that are ingested by organisms are in the form of simple compounds. Plants absorb dissolved elements in soils, which are subsequently ingested by the herbivores and omnivores that eat them, and the elements move up the food chain.
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At least twenty chemical elements are known to be required to support human biochemical processes by serving structural and functional roles as well as electrolytes. Oxygen, hydrogen, carbon and nitrogen are the most abundant elements in the body by weight and make up about 96% of the weight of a human body. Calcium makes up 920 to 1200 grams of adult body weight, with 99% of it contained in bones and teeth. This is about 1.5% of body weight.
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As constituent elements, they did not contradict the chemistry of displacement but transcended it: the chemist could never isolate or characterize an element as he characterized a body; an element was not isolable, for it could not be separated from a mixt without re-creating a new mixt in the process. In his book The Sceptical Chymist of 1661, Robert Boyle criticized the traditional understanding of the composition of materials and initiated the modern understanding of chemical elements.
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Once a materials scientist knows about this structure-property correlation, they can then go on to study the relative performance of a material in a given application. The major determinants of the structure of a material and thus of its properties are its constituent chemical elements and the way in which it has been processed into its final form. These characteristics, taken together and related through the laws of thermodynamics and kinetics, govern a material's microstructure, and thus its properties.
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This melts the scrap, lowers the carbon content of the molten iron and helps remove unwanted chemical elements. It is this use of pure oxygen (instead of air) that improves upon the Bessemer process, as the nitrogen (an undesirable element) and other gases in air do not react with the charge, and decrease efficiency of furnace.McGannon, p 486 # Fluxes (burnt lime or dolomite) are fed into the vessel to form slag, to maintain basicity above 3 and absorb impurities during the steelmaking process.
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The Demonstration of a Compact X-ray Spectrometer was an X-ray telescope for the identification of chemical elements on the lunar surface. It detected the x-ray fluorescence (XRF) of crystal compounds created through the interaction of the electron shell with the solar wind particles to measure the abundance of the three main components: magnesium, silicon and aluminium. The detection of iron, calcium and titanium depended on the solar activity. The detection range for x-rays was 0.5 to 10 keV.
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Sneden (1973). This paper contains also the description of the first version of the code and has been cited about 240 times as of 2008-04-24 by publications in international journals studying the abundances of chemical elements in stars. The software package has been developed and is maintained by Christopher Sneden, University of Texas at Austin. The current supported version of the code was released in August 2010 and is described in the MOOG User's Guide (see references below).
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If supported, the scope of the search can be constrained by the exclusion of certain chemical elements. More sophisticated algorithms depend on the material type covered. Organic compounds might be searched for on the basis of certain molecular fragments. Inorganic compounds, on the other hand, might be of interest with regard to a certain type of coordination geometry. More advanced algorithms deal with conformation analysis (organics), supramolecular chemistry (organics), interpolyhedral connectivity (‘non-organics’) and higher-order molecular structures (biological macromolecules).
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The currently accepted names and symbols of the chemical elements are determined by the International Union of Pure and Applied Chemistry (IUPAC), usually following recommendations by the recognized discoverers of each element. However the names of several elements have been the subject of controversies until IUPAC established an official name. In most cases the controversy was due to a priority dispute as to who first found conclusive evidence for the existence of an element, or as to what evidence was in fact conclusive.
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The name and symbol were officially endorsed by IUPAC on 19 February 2010. The heaviest element that is believed to have been synthesized to date is element 118, oganesson, on 9 October 2006, by the Flerov Laboratory of Nuclear Reactions in Dubna, Russia. Tennessine, element 117 was the latest element claimed to be discovered, in 2009. On 28 November 2016, scientists at the IUPAC officially recognized the names for four of the newest chemical elements, with atomic numbers 113, 115, 117, and 118.
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Hiärneite is an oxide mineral named after the Swedish geologist Urban Hiärne (1641-1727).Nationalencyklopedin online The mineral can be found in rocks that mainly consists of fine grained phlogopite. Hiärneite is the first known mineral that contains both of the chemical elements antimony and zirconium.from Naturhistoriska riksmuseet (translation from Swedish ~: Swedish Museum of Natural History) The mineral was described in 1997 for its occurrence in a skarn environment in Långban iron–manganese deposit of the Filipstad district, Värmland, Sweden.
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In 1794, Anders Gustav Ekeberg began teaching at Uppsala. He was a supporter of Antoine Lavoisier's proposals for systematizing chemical nomenclature. In 1795 he and Pehr von Afzelius published the first article to introduce the modern names for chemical elements such as hydrogen, nitrogen, and oxygen into the Swedish language, "On the Present State of Chemical Sciences". He was made docent in chemistry in 1794 and experimentator (laborator) in 1799, working as a demonstrator in the laboratory of Torbern Bergman.
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Group 11, by modern IUPAC numbering, is a group of chemical elements in the periodic table, consisting of copper (Cu), silver (Ag), and gold (Au). Roentgenium (Rg) is also placed in this group in the periodic table, although no chemical experiments have yet been carried out to confirm that it behaves like the heavier homologue to gold. Group 11 is also known as the coinage metals, due to their former usage. They were most likely the first three elements discovered.
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A compound semiconductor is a semiconductor compound composed of chemical elements of at least two different species. These semiconductors typically form in periodic table groups 13–15 (old groups III–V), for example of elements from the Boron group (old group III, boron, aluminium, gallium, indium) and from group 15 (old group V, nitrogen, phosphorus, arsenic, antimony, bismuth). The range of possible formulae is quite broad because these elements can form binary (two elements, e.g. gallium(III) arsenide (GaAs)), ternary (three elements, e.g.
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The history of the periodic table is also a history of the discovery of the chemical elements. The first person in history to discover a new element was Hennig Brand, a bankrupt German merchant. Brand tried to discover the philosopher's stone—a mythical object that was supposed to turn inexpensive base metals into gold. In 1669 (or later), his experiments with distilled human urine resulted in the production of a glowing white substance, which he called "cold fire" (kaltes Feuer).
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Soon after the Big Bang, which occurred roughly 14 Gya, the only chemical elements present in the universe were hydrogen, helium, and lithium, the three lightest atoms in the periodic table. These elements gradually came together to form stars. These early stars were massive and short-lived, producing heavier elements through stellar nucleosynthesis. Carbon, currently the fourth most abundant chemical element in the universe (after hydrogen, helium and oxygen), was formed mainly in white dwarf stars, particularly those bigger than two solar masses.
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Thirteen chemical elements have a standard atomic weight that is defined not as a single number, but as an interval. For example, hydrogen has . This notation states that the various sources on Earth have substantially different isotopic constitutions, and uncertainties are incorporated in the two numbers. For these elements, there is not an 'Earth average' constitution, and the 'right' value is not its middle (that would be 1.007975 for hydrogen, with an uncertainty of (±0.000135) that would make it just cover the interval).
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Across the base game and DLC, there are a total of 120 levels named after chemical elements and organized on a periodic table with the last two being fictional elements due to the periodic table ending at 118. Each level has achievements for completing the stage within the time limit, obtaining all atoms, and completing with 100% of mercury remaining. All achievements can be obtained individually via multiple playthroughs. Collecting achievements allows players to unlock bonus levels and challenge levels.
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Estimated abundances of the chemical elements in the Solar system. Hydrogen and helium are most common, from the Big Bang. The next three elements (lithium, beryllium, and boron) are rare because they are poorly synthesised in the Big Bang and also in stars. The two general trends in the remaining stellar- produced elements are: (1) an alternation of abundance in elements as they have even or odd atomic numbers, and (2) a general decrease in abundance, as elements become heavier.
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Physical principles indicate that complex antimatter atomic nuclei are possible, as well as anti-atoms corresponding to the known chemical elements. There is strong evidence that the observable universe is composed almost entirely of ordinary matter, as opposed to an equal mixture of matter and antimatter. This asymmetry of matter and antimatter in the visible universe is one of the great unsolved problems in physics. The process by which this inequality between matter and antimatter particles developed is called baryogenesis.
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The Pauli exclusion principle helps explain a wide variety of physical phenomena. One particularly important consequence of the principle is the elaborate electron shell structure of atoms and the way atoms share electrons, explaining the variety of chemical elements and their chemical combinations. An electrically neutral atom contains bound electrons equal in number to the protons in the nucleus. Electrons, being fermions, cannot occupy the same quantum state as other electrons, so electrons have to "stack" within an atom, i.e.
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Canadian Copper Company, at Greater Sudbury, in 1913. These converters refined a matte with 36% Ni+Cu, in a matte containing 80% Ni+Cu. The Manhès–David process is a refining process of the copper mattes, invented in 1880 by the French industrialist Pierre Manhès and his engineer . Inspired by the Bessemer process, it consists of the use of a converter to oxidise with air the undesirable chemical elements (mainly iron and sulfur) contained in the matte, to transform it into copper.
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About 29 chemical elements play active roles in living organisms on Earth. About 95% of living matter is built upon only six elements: carbon, hydrogen, nitrogen, oxygen, phosphorus and sulfur. These six elements form the basic building blocks of virtually all life on Earth, whereas most of the remaining elements are found only in trace amounts. The unique characteristics of carbon make it unlikely that it could be replaced, even on another planet, to generate the biochemistry necessary for life.
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This includes nuclear power, nuclear weapons, nuclear medicine and magnetic resonance imaging, industrial and agricultural isotopes, ion implantation in materials engineering, and radiocarbon dating in geology and archaeology. Such applications are studied in the field of nuclear engineering. Particle physics evolved out of nuclear physics and the two fields are typically taught in close association. Nuclear astrophysics, the application of nuclear physics to astrophysics, is crucial in explaining the inner workings of stars and the origin of the chemical elements.
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This cut-away illustrates a model of the interior of Jupiter, with a rocky core overlaid by a deep layer of metallic hydrogen. In planetary science, volatiles are the group of chemical elements and chemical compounds with low boiling points that are associated with a planet's or moon's crust or atmosphere. Examples include nitrogen, water, carbon dioxide, ammonia, hydrogen, methane and sulfur dioxide. In astrogeology, these compounds, in their solid state, often comprise large proportions of the crusts of moons and dwarf planets.
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According to metaphysical naturalism, if nature is all there is, just as natural cosmological processes, e.g. quantum fluctuations from a multiverse, lead to the Big Bang, and stellar nucleosynthesis brought upon the earliest chemical elements, the formation of the Solar System and the processes involved in abiogenesis arose from natural causes.Richard Carrier, [The Argument from Biogenesis: Probabilities Against a Natural Origin of Life], Biology and Philosophy 19.5 (November 2004), pp. 739-64. Naturalists reason about how, not if evolution happened.
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Chemical elements on Earth cycle through atmospheric, terrestrial, and aquatic environments in a process called biogeochemical cycling. Mercury goes through its own version of biogeochemical cycling named the mercury cycle where it circulates through the environment and changes between oxidation states: Hg(0), Hg(I), Hg(II). When mercury is present in the environment microbial organisms can uptake the elemental form of mercury. This signals the transcription of the genes hgcA and hgcB are transcribed to synthesize the HgcA and HgcB proteins.
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In 1896, Henri Becquerel discovered radioactive decay in a variety of chemical elements. Subsequently, the beta radiation from these decays was discovered to be the emission of a negatively charged particle. Later these particles were identified with the electron, discovered in cathode ray experiments by J. J. Thomson in 1897. This was connected with the theoretical prediction of the electromagnetic mass by J. J. Thomson in 1881, who showed that the electromagnetic energy contributes to the mass of a moving charged body.
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Once a materials scientist knows about this structure-property correlation, they can then go on to study the relative performance of a material in a certain application. The major determinants of the structure of a material and thus of its properties are its constituent chemical elements and the way in which it has been processed into its final form. These characteristics, taken together and related through the laws of thermodynamics and kinetics, govern a material's microstructure, and thus its properties.
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IUPAC was established in 1919 as the successor of the International Congress of Applied Chemistry for the advancement of chemistry. Its members, the National Adhering Organizations, can be national chemistry societies, national academies of sciences, or other bodies representing chemists. There are fifty-four National Adhering Organizations and three Associate National Adhering Organizations. IUPAC's Inter-divisional Committee on Nomenclature and Symbols (IUPAC nomenclature) is the recognized world authority in developing standards for the naming of the chemical elements and compounds.
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The total energy of all particle motion translational and internal, including that of conduction electrons, plus the potential energy of phase changes, plus zero-point energy comprise the internal energy of a substance. Fig. 8 When many of the chemical elements, such as the noble gases and platinum-group metals, freeze to a solid — the most ordered state of matter — their crystal structures have a close-packed arrangement. This yields the greatest possible packing density and the lowest energy state.
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Some heavier elements are produced by less efficient processes such as the r-process and s-process. Elements with atomic numbers close to iron are produced in large quantities in supernova due to explosive oxygen and silicon fusion, followed by radioactive decay of nuclei such as Nickel-56. On average, heavier elements are less abundant in the universe, but some of those near iron are comparatively more abundant than would be expected from this trend. Abundances of the chemical elements in the Solar System.
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Elser's research focuses on ecological stoichiometry, how the balance of chemical elements and affects ecological systems. Particular contributions include global analyses of the nutrient limitation of primary producers, the stoichiometry of nutrient recycling, and the linkage between the phosphorus and RNA content of organisms and their growth rate (the Growth Rate Hypothesis). This work is summarized in the 2002 book Ecological Stoichiometry, co-authored with Robert Sterner. Elser has also organized Woodstoich, a series of four workshops on ecological stoichiometry for early career researchers.
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A sample of aluminium A sample of beryllium in elemental form Samples of yttrium in elemental form Wöhler investigated more than twenty‐five chemical elements during his career. Hans Christian Ørsted was the first to separate out the element aluminium, in 1825, using a reduction of aluminium chloride with a potassium amalgam. Although Ørsted published his findings on the isolation of aluminium in the form of small particles, no other investigators were able to replicate his findings until 1936. Ørsted is now credited with discovering aluminium.
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Uranium ore When Hitchins first worked with Soddy, researchers were still searching for new chemical elements, and isotopes were not yet understood. As early as 1904, researchers had hypothesized that the decay of uranium resulted in the creation of radium, but how this occurred was not clear. In 1907, the American radiochemist Bertram Boltwood had isolated what he believed to be a new intermediate element in the decay chain between uranium and radium, "ionium". Researchers eventually determined that ionium was actually an isotope of thorium, 230Th.
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The nucleus of the lithium atom verges on instability, since the two stable lithium isotopes found in nature have among the lowest binding energies per nucleon of all stable nuclides. Because of its relative nuclear instability, lithium is less common in the solar system than 25 of the first 32 chemical elements even though its nuclei are very light: it is an exception to the trend that heavier nuclei are less common.Numerical data from: Graphed at :File:SolarSystemAbundances.jpg For related reasons, lithium has important uses in nuclear physics.
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In his theory of mineral nutrients, Liebig identified the chemical elements of nitrogen (N), phosphorus (P), and potassium (K) as essential to plant growth. He reported that plants acquire carbon (C) and hydrogen (H) from the atmosphere and from water (H2O). In addition to emphasizing the importance of minerals in the soil, he argued that plants feed on nitrogen compounds derived from the air. This assertion was a source of contention for many years, and turned out to be true for legumes, but not for other plants.
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The lightest chemical elements, primarily hydrogen and helium, were created during the Big Bang through the process of nucleosynthesis. In a sequence of stellar nucleosynthesis reactions, smaller atomic nuclei are then combined into larger atomic nuclei, ultimately forming stable iron group elements such as iron and nickel, which have the highest nuclear binding energies. The net process results in a later energy release, meaning subsequent to the Big Bang. Such reactions of nuclear particles can lead to sudden energy releases from cataclysmic variable stars such as novae.
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Control rod assembly for a pressurized water reactor, above fuel element Control rods are used in nuclear reactors to control the fission rate of uranium or plutonium. Their compositions includes chemical elements such as boron, cadmium, silver, or indium, that are capable of absorbing many neutrons without themselves fissioning. These elements have different neutron capture cross sections for neutrons of various energies. Boiling water reactors (BWR), pressurized water reactors (PWR), and heavy-water reactors (HWR) operate with thermal neutrons, while breeder reactors operate with fast neutrons.
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Beryllium-8 (8Be, Be-8) is a radionuclide with 4 neutrons and 4 protons. It is an unbound resonance and nominally an isotope of beryllium. It decays into two alpha particles with a half-life on the order of 10−16 seconds; this has important ramifications in stellar nucleosynthesis as it creates a bottleneck in the creation of heavier chemical elements. The properties of 8Be have also led to speculation on the fine tuning of the Universe, and theoretical investigations on cosmological evolution had 8Be been stable.
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Computational thermodynamics is the use of computers to simulate thermodynamic problems specific to materials science, particularly used in the construction of phase diagrams. Several open and commercial programs exist to perform these operations. The concept of the technique is minimization of Gibbs free energy of the system; the success of this method is due not only to properly measuring thermodynamic properties, such as those in the list of thermodynamic properties, but also due to the extrapolation of the properties of metastable allotropes of the chemical elements.
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It was also believed that radioactive decay violated one of the central principles of the periodic table, namely that chemical elements could not undergo transmutations and always had unique identities. Frederick Soddy and Kazimierz Fajans found in 1913 that although these substances emitted different radiation, many of these substances were identical in their chemical characteristics, so shared the same place on the periodic table. They became known as isotopes, from the Greek ' ("same place").Soddy first used the word "isotope" in: See p. 400.
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Antimony has consistently been ranked high in European and US risk lists concerning criticality of the element indicating the relative risk to the supply of chemical elements or element groups required to maintain the current economy and lifestyle. With most of the antimony imported into Europe and the US coming from China, Chinese production is critical to supply. As China is revising and increasing environmental control standards, antimony production is becoming increasingly restricted. Additionally Chinese export quotas for antimony have been decreasing in the past years.
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After five years at Princeton, as part of an ongoing collaboration between Russell and research groups there, she moved to the Mount Wilson Observatory where she worked extensively on solar spectroscopy, analyzing the spectral lines of the Sun and thereby identifying the chemical elements in the Sun. With her collaborators, she analyzed the spectra of sunspots. Moore was able to deduce the temperature of sunspots to be about 4,700 degrees kelvin.Elizabeth Landau, "How Charlotte Moore Sitterly Wrote The Encyclopedia of Starlight," Smithsonian, September 23, 2019.
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A space-filling model of the diatomic molecule dinitrogen, N2 Diatomic molecules are molecules composed of only two atoms, of the same or different chemical elements. The prefix di- is of Greek origin, meaning "two". If a diatomic molecule consists of two atoms of the same element, such as hydrogen (H2) or oxygen (O2), then it is said to be homonuclear. Otherwise, if a diatomic molecule consists of two different atoms, such as carbon monoxide (CO) or nitric oxide (NO), the molecule is said to be heteronuclear.
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The bond in a homonuclear diatomic molecule is non-polar. A periodic table showing the elements that exist as homonuclear diatomic molecules under typical laboratory conditions. The only chemical elements that form stable homonuclear diatomic molecules at standard temperature and pressure (STP) (or typical laboratory conditions of 1 bar and 25 °C) are the gases hydrogen (H2), nitrogen (N2), oxygen (O2), fluorine (F2), and chlorine (Cl2). The noble gases (helium, neon, argon, krypton, xenon, and radon) are also gases at STP, but they are monatomic.
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The discovery of the 118 chemical elements known to exist as of 2020 is presented in chronological order. The elements are listed generally in the order in which each was first defined as the pure element, as the exact date of discovery of most elements cannot be accurately determined. There are plans to synthesise more elements, and it is not known how many elements are possible. Each element's name, atomic number, year of first report, name of the discoverer, and notes related to the discovery are listed.
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Titanium alloys are alloys that contain a mixture of titanium and other chemical elements. Such alloys have very high tensile strength and toughness (even at extreme temperatures). They are light in weight, have extraordinary corrosion resistance and the ability to withstand extreme temperatures. However, the high cost of both raw materials and processing limit their use to military applications, aircraft, spacecraft, bicycles, medical devices, jewelry, highly stressed components such as connecting rods on expensive sports cars and some premium sports equipment and consumer electronics.
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Phosphorus occurs in amounts of about 2/3 of calcium, and makes up about 1% of a person's body weight. The other major minerals (potassium, sodium, chlorine, sulfur and magnesium) make up only about 0.85% of the weight of the body. Together these eleven chemical elements (H, C, N, O, Ca, P, K, Na, Cl, S, Mg) make up 99.85% of the body. The remaining ~18 ultratrace minerals comprise just 0.15% of the body, or about one hundred grams in total for the average person.
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The s-process is secondary, meaning that it requires pre-existing heavy isotopes as seed nuclei to be converted into other heavy nuclei by a slow sequence of captures of free neutrons. The r-process scenarios create their own seed nuclei, so they might proceed in massive stars that contain no heavy seed nuclei. Taken together, the r- and s-processes account for almost the entire abundance of chemical elements heavier than iron. The historical challenge has been to locate physical settings appropriate for their time scales.
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Each branch of the s-process reaction chain eventually terminates at a cycle involving lead, bismuth, and polonium. The s-process contrasts with the r-process, in which successive neutron captures are rapid: they happen more quickly than the beta decay can occur. The r-process dominates in environments with higher fluxes of free neutrons; it produces heavier elements and more neutron-rich isotopes than the s-process. Together the two processes account for most of the relative abundance of chemical elements heavier than iron.
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Salts were identified by the suffix -an added to the noun. Many of the terms created by Presl derive from Latin, German or Russian; only some were retained in use. A similar attempt, published in "Orbis pictus" (1852), by Karel Slavoj Amerling (1807-1884) to create Czech names for the chemical elements (and to order the elements into a structure, similar to the work of Russian chemist Nikolay Beketov) was not successful. Later work on the nomenclature was performed by Vojtěch Šafařík (1829-1902).
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Stan Woosley's research centers on theoretical high-energy astrophysics, especially violent explosive events such as supernovae and gamma ray bursts. A supernova occurs when the core of a star collapses under the gravitational force of its own mass. The resulting explosion can be as bright as an entire galaxy, releasing immense amounts of energy. The explosion also spews into space all of the chemical elements forged by nuclear fusion reactions during the life of the star and some that are formed during the explosion itself.
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No automated software was used to clean up the film's repaired and digitised photo-chemical elements. The work was done by hand, a single frame at a time, by 40 to 60 trained digital artists, over several months. In addition to the DVD and Blu-ray re-release, the restored version also received a limited theatrical run in May 2012. For the 50th anniversary of the film, the soundtrack and score were remixed in 5.1 stereo surround sound at Abbey Road Studios by mix engineer Peter Cobbin.
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William Thomson, later to become Lord Kelvin, became concerned with the nature of Dalton's chemical elements, whose atoms appeared in only a few forms but in vast numbers. He was inspired by Helmholz' findings, reasoning that the aether, a substance then hypothesised to pervade all of space, should be capable of supporting such stable vortices. According to Helmholtz’ theorems, these vortices would correspond to different kinds of knot. Thomson suggested that each type of knot might represent an atom of a different chemical element.
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The B2FH paper was a landmark scientific paper on the origin of the chemical elements. The paper's title is "Synthesis of the Elements in Stars", but it became known as B2FH from the initials of its authors: Margaret Burbidge, Geoffrey Burbidge, William A. Fowler, and Fred Hoyle. It was written from 1955–56 at the University of Cambridge and Caltech, then published in Reviews of Modern Physics in 1957. The B2FH paper reviewed stellar nucleosynthesis theory and supported it with astronomical and laboratory data.
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Deep-level traps shorten the non-radiative life time of charge carriers, and—through the Shockley–Read–Hall (SRH) process—facilitate recombination of minority carriers, having adverse effects on the semiconductor device performance. Hence, deep-level traps are not appreciated in many opto-electronic devices as it may lead to poor efficiency and reasonably large delay in response. Common chemical elements that produce deep-level defects in silicon include iron, nickel, copper, gold, and silver. In general, transition metals produce this effect, while light metals such as aluminium do not.
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Hayes eventually moved into Sacks' building, though they maintained separate apartments. In Insomniac City, Hayes reverently describes Sacks' unique and curious mind. The two would use marijuana together (Sacks preferred edibles, and always called it "cannabis"), and Sacks would report on vivid visual hallucinations, partly owing to his significantly impaired eyesight. Sacks was an eccentric: he was fascinated by the chemical elements, insisted on wearing swim goggles to open a bottle of champagne, and was utterly unaware of popular culture (he did not know who Michael Jackson was).
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Chemical elements are defined by their number of protons, but the mass of the atom is determined by the number of protons and neutrons in the nucleus. Isotopes are atoms that are of a specific element, but have different numbers of neutrons and thus different masses. In a specific object, you can have a ratio between two isotopes of an element. This ratio varies slightly in the world, so in order to study isotopic ratio changes across the world, changes in isotope ratios are defined as deviations from a standard, multiplied by 1000.
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The lanthanide () or lanthanoid () series of chemical elementsThe current IUPAC recommendation is that the name lanthanoid be used rather than lanthanide, as the suffix "-ide" is preferred for negative ions, whereas the suffix "-oid" indicates similarity to one of the members of the containing family of elements. However, lanthanide is still favored in most (~90%) scientific articles and is currently adopted on Wikipedia. In the older literature, the name "lanthanon" was often used. comprises the 15 metallic chemical elements with atomic numbers 57-71, from lanthanum through lutetium.
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Gerolsteiner Brunnen GmbH & Co. KG (Gerolsteiner) is a leading German mineral water firm with its seat in Gerolstein in the Eifel mountains. It is well known for its Gerolsteiner Sprudel brand, a bottled, naturally carbonated mineral water. This water, in addition to hydrogen and oxygen (H2O) and carbon (in the carbon dioxide (CO2) carbonation), contains at least the following chemical elements in amounts of 100 or more micrograms per liter: bromine, calcium, chlorine, fluorine, lithium, magnesium, manganese, nitrogen, potassium, silicon, sodium, strontium, and sulfur. The strontium is naturally occurring, not the radioactive strontium-90.
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Yuri Tsolakovich Oganessian ( ; born 14 April 1933) is a Russian nuclear physicist of Armenian descent who is considered the world's leading researcher in superheavy chemical elements. He led the discovery of these elements in the periodic table. He succeeded Georgy Flyorov as director of the Flerov Laboratory of Nuclear Reactions at the Joint Institute for Nuclear Research in 1989 and is now its scientific leader. The heaviest element on the periodic table, oganesson, is named after him, only the second time that an element was named after a living scientist (the other being seaborgium).
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In the 1970s, Oganessian invented the method of cold fusion, a technique to produce transactinide elements (superheavy elements). It played a vital role in the discoveries of elements from 106 to 113. From the mid-1970s to the mid-1990s, the partnership of JINR, led by Oganessian, and the GSI Helmholtz Centre for Heavy Ion Research in Germany, led to the discovery of six chemical elements (107 to 112): bohrium, meitnerium, hassium, darmstadtium, roentgenium, and copernicium. His newer technique, called hot fusion, helped to discover the rest of the superheavy elements (elements 113–118).
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BBC, 2009 In Europe, the Ancient Greek system of Aristotle evolved slightly into the medieval system, which for the first time in Europe became subject to experimental verification in the 1600s, during the Scientific Revolution. Modern science does not support the classical elements as the material basis of the physical world. Atomic theory classifies atoms into more than a hundred chemical elements such as oxygen, iron, and mercury. These elements form chemical compounds and mixtures, and under different temperatures and pressures, these substances can adopt different states of matter.
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This clumpiness may be caused by a magnetic cycle in the star that is comparable to the solar cycle in the Sun and results in periodic increases in mass loss. Various chemical elements and about 50 molecules have been detected in the outflows from CW Leonis, among others nitrogen, oxygen and water, silicon and iron. One theory was that the star was once surrounded by comets which melted once the star started expanding, but water is now thought to form naturally in the atmospheres of all carbon stars.
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In physics and chemistry, "monatomic" is a combination of the words "mono" and "atomic", and means "single atom". It is usually applied to gases: a monatomic gas is one in which atoms are not bound to each other. Examples at standard conditions include the noble gases argon, krypton, and xenon, though all chemical elements will be monatomic in the gas phase at sufficiently high temperatures. The thermodynamic behavior of a monatomic gas is extremely simple when compared to polyatomic gases because it is free of any rotational or vibrational energy.
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Periodic table for looking up element numbers (atomic number) These isotope tables show all of the known isotopes of the chemical elements, arranged with increasing atomic number from left to right and increasing neutron number from top to bottom. Half lives are indicated by the color of each isotope's cell (see color chart in each section). Colored borders indicate half lives of the most stable nuclear isomer states. The data for these tables came from Brookhaven National Laboratory which has an interactive Table of Nuclides with data on ~3000 nuclides.
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For chemical elements without isolated molecules, such as carbon and metals, the molar mass is computed dividing by the number of moles of atoms instead. Thus, for example, the molar mass of iron is about 55.845g/mol. Between 1971 and 2019, SI defined the "amount of substance" as a separate dimension of measurement, and the mole was defined as the amount of substance that has as many constituent particles as there are atoms in 12 grams of carbon-12. In that period, the molar mass of carbon-12 was thus exactly 12g/mol, by definition.
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The lightest chemical elements are hydrogen and helium, both created by Big Bang nucleosynthesis during the first 20 minutes of the universeSee the timeline on p.10 in in a ratio of around 3:1 by mass (or 12:1 by number of atoms), along with tiny traces of the next two elements, lithium and beryllium. Almost all other elements found in nature were made by various natural methods of nucleosynthesis. On Earth, small amounts of new atoms are naturally produced in nucleogenic reactions, or in cosmogenic processes, such as cosmic ray spallation.
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Several terms are commonly used to characterize the general physical and chemical properties of the chemical elements. A first distinction is between metals, which readily conduct electricity, nonmetals, which do not, and a small group, (the metalloids), having intermediate properties and often behaving as semiconductors. A more refined classification is often shown in colored presentations of the periodic table. This system restricts the terms "metal" and "nonmetal" to only certain of the more broadly defined metals and nonmetals, adding additional terms for certain sets of the more broadly viewed metals and nonmetals.
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In the second half of the twentieth century, physics laboratories became able to produce nuclei of chemical elements with half-lives too short for an appreciable amount of them to exist at any time. These are also named by IUPAC, which generally adopts the name chosen by the discoverer. This practice can lead to the controversial question of which research group actually discovered an element, a question that delayed the naming of elements with atomic number of 104 and higher for a considerable amount of time. (See element naming controversy).
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Quantities, Units and Symbols in Physical Chemistry, commonly known as the Green Book, is a compilation of terms and symbols widely used in the field of physical chemistry. It also includes a table of physical constants, tables listing the properties of elementary particles, chemical elements, and nuclides, and information about conversion factors that are commonly used in physical chemistry. The most recent edition is the third edition (), originally published by IUPAC in 2007. A second printing of the third edition was released in 2008; this printing made several minor revisions to the 2007 text.
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In his studies of meteorites, he identified thirty chemical elements that could also be found in Earth-based rocks. Referring to research of Gustav Kirchhoff (1824–1887) and Robert Wilhelm Bunsen (1811–1899) involving spectral analysis of the Sun, he stated that a unity of chemical composition existed in the solar system. The meteorite collection of the National Museum of Natural History Meunier also performed important geological studies (general and experimental) of the Paris Basin. Meunier was a prolific author, publishing more than 570 works that included around thirty books.
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The sub- theory of GP modelling the internal structure of segments is called Element Theory (ET). Like chemical elements, the melodic primes of ET are phonetically interpretable alone as well as in combinations - hence their name. They are assumed, depending on the version of ET, to correspond to either characteristic acoustic signatures in the signal, or articulatory gestures (or hot features, as previously referred to). Unlike the (binary) distinctive features of Structuralist Phonology and SPE, each element is a monovalent (unary, single-valued) and potentially interpretable phonological expression.
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Carbon is constantly transported between the different elements of the climate system: fixed by living creatures and transported through the ocean and atmosphere. Chemical elements, vital for life, are also constantly cycled through the different components of the climate system. The carbon cycle is directly important for climate as it determines the concentrations of two important greenhouse gases in the atmosphere: and methane. In the fast part of the carbon cycle, plants take up carbon dioxide from the atmosphere using photosynthesis; this is later re-emitted by the breathing of living creatures.
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The team combined data on elemental abundances produced by the Burbidges with Hoyle's hypothesis that all chemical elements might be produced in stars by a series of nuclear reactions, and Fowler's laboratory experiments on those reactions. The idea became known as stellar nucleosynthesis. They published their model in a series of papers, culminating in a magnum opus in 1957, now known as the B2FH paper after the initials of Burbidge, Burbidge, Fowler & Hoyle. Margaret Burbidge was the first author of the paper, which was written while she was pregnant.
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The paper demonstrated that most heavier chemical elements were formed in stellar evolution. The theory they developed remains the fundamental basis for stellar nucleosynthesis. Fowler was later awarded the 1983 Nobel Prize in Physics (shared with Subrahmanyan Chandrasekhar) for his work on nucleosynthesis, and expressed surprise that Burbidge was not included. When Fowler moved back to the US, he advised the Burbidges to come with him to California, suggesting Margaret (the observer) should re-apply for the fellowship at Mount Wilson Observatory while Geoff (the theorist) should seek the Kellogg Fellowship at Caltech.
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Conway's cosmological theorem asserts that every sequence eventually splits ("decays") into a sequence of "atomic elements", which are finite subsequences that never again interact with their neighbors. There are 92 elements containing the digits 1, 2, and 3 only, which John Conway named after the chemical elements up to uranium, calling the sequence audioactive. There are also two "transuranic" elements for each digit other than 1, 2, and 3.Ekhad, S. B., Zeilberger, D.: Proof of Conway's lost cosmological theorem, Electronic Research Announcements of the American Mathematical Society, August 21, 1997, Vol.
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Van Helmont (1579 - 1644) is sometimes considered the founder of pneumatic chemistry, as he was the first natural philosopher to take an interest in air as a reagent. Alessandro Volta began investigating pneumatic chemistry in 1776 and argued that there were different types of inflammable air based on experiments on marsh gases. Pneumatic chemists credited with discovering chemical elements include Joseph Priestley, Henry Cavendish, Joseph Black, Daniel Rutherford, and Carl Scheele. Other individuals who investigated gases during this period include Robert Boyle, Stephen Hales, William Brownrigg, Antoine Lavoisier, Joseph Louis Gay-Lussac, and John Dalton.
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Theodore Richards was born in Germantown, Pennsylvania in 1868, educated at home, and then at Haverford College and Harvard University, where he received his PhD in chemistry in 1888. From an early time he was interested in the question of atomic weights, a subject that he would study for most of his professional career. After his graduation he became an instructor at Harvard, eventually gaining promotion to full professor in 1901. He successfully recalculated the atomic weights of a number of chemical elements, developing methodology and apparatus along the way.
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The lyrics of "The Elements" (Flash animation) are a recitation of the names of all the chemical elements that were known at the time of writing, up to number 102, nobelium. It can be found on his albums Songs & More Songs by Tom Lehrer as well as An Evening Wasted with Tom Lehrer. The song is sung to the tune of Sir Arthur Sullivan's "Major General's Song" ("I am the very model of a modern major-general...") from The Pirates of Penzance. Since that time, 16 more have been discovered.
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For example, Mustafin stated that chemical reaction is similar to a performance, in which all characters are known, and chemical thermodynamics allows one to peep behind the curtain and find out what will become with the heroes of this performance as a result of the chemical reaction. Speaking about chemical elements, he assimilated them to people, differing from each other in their activity and their ability and readiness to come into contact with each other. He knew how to emphasize the main points and select memorable laws. He died suddenly and unexpectedly in December, 1968.
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Charas' Pharmacopée royale contains one of the earliest comprehensive classification of chemical elements and compounds, which can be regarded as the forerunner of chemical symbols and periodic table. His chemical table contains nine elements, namely lead, tin, iron, gold, copper, quicksilver, sulfur, and arsenic (but he listed sulfur and arsenic under minerals or chemical compounds). He assigned chemical symbols to the seven metals corresponding to the known celestial bodies at the time, Saturn, Jupiter, Mars, Sun, Venus, Mercury, and Moon respectively. He used these chemical symbols to predict the chemical properties of chemical compounds.
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An endmember (also end-member or end member) in mineralogy is a mineral that is at the extreme end of a mineral series in terms of purity. Minerals often can be described as solid solutions with varying compositions of some chemical elements, rather than as substances with an exact chemical formula. There may be two or more endmembers in a group or series of minerals. For example, the tectosilicate feldspar can be described as a solid solution of the endmembers K-feldspar [KAlSi3O8], albite [NaAlSi3O8] and anorthite [CaAl2Si2O8].
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By 1912, almost 50 different radioactive substances had been found in the decay chains of thorium and uranium. American chemist Bertram Boltwood proposed several decay chains linking these radioelements between uranium and lead. These were thought at the time to be new chemical elements, substantially increasing the number of known "elements" and leading to speculations that their discoveries would undermine the concept of the periodic table. For example, there was not enough room between lead and uranium to accommodate these discoveries, even assuming that some discoveries were duplicates or incorrect identifications.
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Additionally, X-rays cause fluorescence in most materials, and these emissions can be analyzed to determine the chemical elements of an imaged object. Another use is to generate diffraction patterns, a process used in X-ray crystallography. By analyzing the internal reflections of a diffraction pattern (usually with a computer program), the three- dimensional structure of a crystal can be determined down to the placement of individual atoms within its molecules. X-ray microscopes are sometimes used for these analyses because the samples are too small to be analyzed in any other way.
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Solid samples can also be introduced using laser ablation. The sample enters the central channel of the ICP, evaporates, molecules break apart, and then the constituent atoms ionise. At the temperatures prevailing in the plasma a significant proportion of the atoms of many chemical elements are ionized, each atom losing its most loosely bound electron to form a singly charged ion. The plasma temperature is selected to maximise ionisation efficiency for elements with a high first ionisation energy, while minimising second ionisation (double charging) for elements that have a low second ionisation energy.
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In principle, they can be separated into the component substances by purely mechanical processes. Butter, soil and wood are common examples of mixtures. Grey iron metal and yellow sulfur are both chemical elements, and they can be mixed together in any ratio to form a yellow-grey mixture. No chemical process occurs, and the material can be identified as a mixture by the fact that the sulfur and the iron can be separated by a mechanical process, such as using a magnet to attract the iron away from the sulfur.
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In the work, Boyle presents his hypothesis that every phenomenon was the result of collisions of particles in motion. Boyle appealed to chemists to experiment and asserted that experiments denied the limiting of chemical elements to only the classic four: earth, fire, air, and water. He also pleaded that chemistry should cease to be subservient to medicine or to alchemy, and rise to the status of a science. Importantly, he advocated a rigorous approach to scientific experiment: he believed all theories must be proved experimentally before being regarded as true.
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A technology-critical element (TCE) is a chemical element that is important to emerging technologies, in much higher demand than in the past, and in scarce supply relative to demand. Many advanced engineering applications, like clean- energy production, communications or computing, use emergent technologies that utilize numerous chemical elements. As a result, a much greater proportion of metals in the periodic table are economically significant than in past centuries. Technology-critical elements are those elements for which a striking acceleration in usage has emerged, relative to past consumption.
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According to the BGS Risk List 2015, antimony is ranked second highest (after rare earth elements) on the relative supply risk index. This indicates that it has currently the second highest supply risk for chemical elements or element groups which are of economic value to the British economy and lifestyle. Furthermore, antimony was identified as one of 20 critical raw materials for the EU in a report published in 2014 (which revised the initial report published in 2011). As seen in Figure xxx antimony maintains high supply risk relative to its economic importance.
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Examples include the element carbon and the organic compounds. The chemical elements are often displayed in a periodic table that is laid out to display recurring chemical properties, and elements with the same number of valence electrons form a group that is aligned in the same column of the table. (The horizontal rows correspond to the filling of a quantum shell of electrons.) The elements at the far right of the table have their outer shell completely filled with electrons, which results in chemically inert elements known as the noble gases.
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Intrinsically valuable currencies are used in the Frank Herbert's Dune universe; the Dragonlance world of Krynn where steel coins are the primary currency and are more valuable than gold by weight; and the Apprentice Adept series by Piers Anthony. The space opera Consider Phlebas by Iain M. Banks features coins convertible for chemical elements, land, or computers. In utopian fiction, a money-free economy may still need a unit of exchange: in The Great Explosion by Eric Frank Russell, the Gands use favor- exchange based on "obs" (obligations).
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The definitions surveyed in this article encompass up to 96 out of the 118 known chemical elements; only mercury, lead and bismuth meet all of them. Despite this lack of agreement, the term (plural or singular) is widely used in science. A density of more than 5 g/cm3 is sometimes quoted as a commonly used criterion and is used in the body of this article. The earliest known metals—common metals such as iron, copper, and tin, and precious metals such as silver, gold, and platinum—are heavy metals.
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Periodic table for looking up element numbers (atomic number) These isotope tables show all of the known isotopes of the chemical elements, arranged with increasing atomic number from left to right and increasing neutron number from top to bottom. Half lives are indicated by the color of each isotope's cell (see color chart in each section). Colored borders indicate half lives of the most stable nuclear isomer states. The data for these tables came from Brookhaven National Laboratory which has an interactive Table of Nuclides with data on ~3000 nuclides.
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William Hyde Wollaston in 1802 and Joseph von Fraunhofer in 1814 described the dark lines within the solar spectrum. Later, Gustav Kirchhoff explained the lines by atomic absorption or emission, which allowed the lines to be used for the identification of chemical elements. In the early days of telescopic astronomy, the word nebula was used to describe any fuzzy patch of light that did not look like a star. Many of these, such as the Andromeda Nebula, had spectra that looked like stellar spectra, and these turned out to be galaxies.
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Gadolin 1794 Anders Gustaf Ekeberg confirmed the identification in 1797 and named the new oxide yttria. In the decades after Antoine Lavoisier developed the first modern definition of chemical elements, it was believed that earths could be reduced to their elements, meaning that the discovery of a new earth was equivalent to the discovery of the element within, which in this case would have been yttrium. Friedrich Wöhler is credited with first isolating the metal in 1828 by reacting a volatile chloride that he believed to be yttrium chloride with potassium.Heiserman, David L. (1992).
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Her pictures from the Mount Wilson Observatory helped redetermine the new International Angstrom scale. She earned a Ph.D. in astronomy in 1931 from the University of California, Berkeley on a Lick Fellowship; she was not able to study at Princeton because they did not accept women - and would not for the next 30 years. While working on her Ph.D, she continued researching spectroscopy and collected and analyzed data about the spectra of chemical elements and molecules. After obtaining her Ph.D, she returned to Princeton to continue work with Russell as a research assistant.
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Cartridges of uranium were irradiated in the Windscale reactors to produce plutonium. The cartridges were pushed through the reactor, and exited on the other side, where they fell into submerged steel skips which were pulled into a deep cooling pond. After being irradiated, each cartridge contained as many as 180 isotopes of 35 different chemical elements. Less than half of one per cent of the feed would have been converted to plutonium, but about 5 per cent was now radioactive fission products, the remainder being slightly depleted uranium.
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Solar flare photographed in the light of ionized helium, using the extreme- ultraviolet spectroheliograph of the U.S. Naval Research Laboratory. The spectroheliograph is an instrument used in astronomy which captures a photographic image of the Sun at a single wavelength of light, a monochromatic image. The wavelength is usually chosen to coincide with a spectral wavelength of one of the chemical elements present in the Sun. It was developed independently by George Ellery Hale and Henri-Alexandre Deslandres in the 1890s and further refined in 1932 by Robert R. McMath to take motion pictures.
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The concept of a nuclear chain reaction brought about by nuclear reactions mediated by neutrons was first realized shortly thereafter, by Hungarian scientist Leó Szilárd, in 1933. He filed a patent for his idea of a simple reactor the following year while working at the Admiralty in London.L. Szilárd, "Improvements in or relating to the transmutation of chemical elements," British patent number: GB630726 (filed: 28 June 1934; published: 30 March 1936). However, Szilárd's idea did not incorporate the idea of nuclear fission as a neutron source, since that process was not yet discovered.
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Around 1% of the mass of HH objects is made up of heavier chemical elements, including oxygen, sulfur, nitrogen, iron, calcium and magnesium. Abundances of these elements, determined from emission lines of respective ions, are generally similar to their cosmic abundances. Many chemical compounds found in the surrounding interstellar medium, but not present in the source material, such as metal hydrides, are believed to have been produced by shock-induced chemical reactions. Around 20–30% of the gas in HH objects is ionized near the source star, but this proportion decreases at increasing distances.
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In the work, Boyle presents his hypothesis that every phenomenon was the result of collisions of particles in motion. Boyle appealed to chemists to experiment and asserted that experiments denied the limiting of chemical elements to only the classic four: earth, fire, air, and water. He also pleaded that chemistry should cease to be subservient to medicine or to alchemy, and rise to the status of a science. Importantly, he advocated a rigorous approach to scientific experiment: he believed all theories must be tested experimentally before being regarded as true.
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Methane, CH4, space-filling, van der Waal's-based representation, carbon (C ) in black, hydrogen (H) in white. In chemistry, a space-filling model is a type of three-dimensional (3D) molecular model where the atoms are represented by spheres whose radii are, either as van der Waals radii or otherwise, proportional to the radii of the atoms. Center-to-center distances of the atoms are proportional to the distances between the atomic nuclei, all in the same scale. Atoms of different chemical elements are usually represented by spheres of different colors, see below.
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Working at the Cavendish Laboratory, established by Maxwell, J. J. Thompson directed a dedicate experiment demonstrating that cathode rays were in fact negatively charged particles, now called electrons. The experiment enabled Thompson to calculate the ratio between the magnitude of the charge and the mass of the particle (q/m). In addition, because the ratio was the same regardless of the metal used, Thompson concluded that electrons must be a constituent of all atoms. Although the atoms of each chemical elements have different numbers of electrons, all electrons are identical.
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While the term 'substance' in 'substance flow analysis (SFA) always refers to chemical substances, the term 'material' in 'material flow analysis (MFA)' has a much wider scope. According to Brunner and Rechberger the term 'material' comprises substances AND goods, and the reason for this wide scope is the wish to apply MFA not only to chemical elements or substances but also to materials like steel, timber, or products like cars or buildings. It is thus possible to conduct an MFA for the passenger vehicle fleet by recording the vehicles entering and leaving the use phase.
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Tetrakis(hexahydropyrimidinopyrimidine)ditungsten(II), known as ditungsten tetra(hpp), is the name of the coordination compound with the formula W2(hpp)4. This material consists of a pair of tungsten centers linked by the conjugate base of four hexahydropyrimidopyrimidine (hpp) ligands. It adopts a structure sometimes called a Chinese lantern structure or paddlewheel compound, the prototype being copper(II) acetate. The hpp ligand anion The molecule is of research interest because it has the lowest ionization energy (3.51 eV) of all stable chemical elements or chemical compounds as of the year 2005.
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Next, the plutonium and uranium are available for making nuclear-energy materials, such as new reactor fuel and nuclear weapons. The ion-exchange process is also used to separate other sets of very similar chemical elements, such as zirconium and hafnium, which is also very important for the nuclear industry. Physically, zirconium is practically transparent to free neutrons, used in building nuclear reactors, but hafnium is a very strong absorber of neutrons, used in reactor control rods. Thus, ion-exchange is used in nuclear reprocessing and the treatment of radioactive waste.
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The book received mixed but generally positive reviews from The Daily Telegraph, Kirkus Reviews, Publishers Weekly, and Science News. The Telegraph described the book as "a 400-page love letter to the chemical elements", and "an agreeable jumble of anecdote, reflection and information, rather than a source of understanding". Robert Buntrock, reviewing the book for the Journal of Chemical Education, found it to be more accurate and more enjoyable than The Disappearing Spoon by Sam Kean, a book with similar subject matter and audience published the year before.
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Ytterby quarry ASM International society at the entrance of Ytterby mine Terbiumvägen (Terbium Road) and Gruvvägen (Mine Road) close to the Ytterby mine () Ytterby () is a village on the Swedish island of Resarö, in Vaxholm Municipality in the Stockholm archipelago. Today the residential area is dominated by suburban homes. The name of the village translates to "outer village". Ytterby is perhaps most famous for being the single richest source of elemental discoveries in the world; the chemical elements yttrium (Y), terbium (Tb), erbium (Er), and ytterbium (Yb) are all named after Ytterby.
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His experiments helped to support the interpretation given by Einstein in 1905. In 1925 he developed the first spectrograph with a concave, reflective, and vacuum network which worked in the far ultra-violet up to wavelengths of up to 20 nm. The tables of wavelengths established with this apparatus on 30 chemical elements, and their variously charged ions, are still in use. In 1940 Eugene Bloch was dismissed from his professorship following the anti-Jewish laws of the Vichy government and had to leave the Ecole Normale Superieure.
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The periodic table of mathematical shapes is popular name given to a project to classify Fano varieties. The project was thought up by Professor Alessio Corti, from the Department of Mathematics at Imperial College London. It aims to categorise all three-, four- and five-dimensional shapes into a single table, analogous to the periodic table of chemical elements. It is meant to hold the equations that describe each shape and, through this, mathematicians and other scientists expect to develop a better understanding of the shapes’ geometric properties and relations.
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They used radiometric methods to identify which stream the radioactivity was in after each chemical separation; they separated the uranium ore into each of the different chemical elements that were known at the time, and measured the radioactivity of each fraction. They then attempted to separate these radioactive fractions further, to isolate a smaller fraction with a higher specific activity (radioactivity divided by mass). In this way, they isolated polonium and radium. It was noticed in about 1901 that high doses of radiation could cause an injury in humans.
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The Periodic Law: the number affixed to an element is the number of "Anu" (the ultimate physical particles of which matter is constituted). Occult Chemistry: Investigations by Clairvoyant Magnification into the Structure of the Atoms of the Periodic Table and Some Compounds (originally subtitled A Series of Clairvoyant Observations on the Chemical Elements) is a book written by Annie Besant and C.W. Leadbeater, who were all members of the Theosophical Society based in Adyar, India. Besant was at the time the President of the Society having succeeded Henry Olcott after his death in 1907.
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Specific protein complexes, known as histone-modifying complexes catalyze addition or removal of various chemical elements on histones. These enzymatic modifications include acetylation, methylation, phosphorylation, and ubiquitination and primarily occur at N-terminal histone tails. Such modifications affect the binding affinity between histones and DNA, and thus loosening or tightening the condensed DNA wrapped around histones, e.g., Methylation of specific lysine residues in H3 and H4 causes further condensation of DNA around histones, and thereby prevents binding of transcription factors to the DNA that lead to gene repression.
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I-III-VI2 semiconductors are solid semiconducting materials that contain three or more chemical elements belonging to groups I, III and VI (IUPAC groups 1/11, 13 and 16) of the periodic table. They usually involve two metals and one chalcogen. Some of these materials have a direct bandgap, Eg, of approximately 1.5 eV, which makes them efficient absorbers of sunlight and thus potential solar cell materials. A fourth element is often added to a I-III-VI2 material to tune the bandgap for maximum solar cell efficiency.
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In North America, the earliest dog remains were found in Illinois and radiocarbon dating indicates 9,900 YBP. These include three isolated burials at the Koster Site near the lower Illinois River in Greene County, and one burial 35 km away at the Stilwell II site in Pike County. These dogs were medium-sized adults around in height and around in weight, with very active lifestyles and varied morphologies. Isotope analysis can be used to identify some chemical elements, allowing researchers to make inferences about the diet of a species.
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Cross- section details of a long bone The hard outer layer of bones is composed of cortical bone, which is also called compact bone as it is much denser than cancellous bone. It forms the hard exterior (cortex) of bones. The cortical bone gives bone its smooth, white, and solid appearance, and accounts for 80% of the total bone mass of an adult human skeleton. It facilitates bone's main functions—to support the whole body, to protect organs, to provide levers for movement, and to store and release chemical elements, mainly calcium.
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Alpha, beta, and gamma are the first three letters of the Greek alphabet. In 1900, Becquerel measured the mass-to-charge ratio () for beta particles by the method of J.J. Thomson used to study cathode rays and identify the electron. He found that for a beta particle is the same as for Thomson's electron, and therefore suggested that the beta particle is in fact an electron. In 1901, Rutherford and Frederick Soddy showed that alpha and beta radioactivity involves the transmutation of atoms into atoms of other chemical elements.
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Radical theory is an obsolete scientific theory in chemistry describing the structure of organic compounds. The theory was pioneered by Justus von Liebig, Friedrich Wöhler and Auguste Laurent around 1830 and is not related to the modern understanding of free radicals.The Oxford Companion to the History of Modern Science John L. Heilbron Ed. 2003Organic chemistry in the nineteenth century, Rochelle Forrester 2006 Link In this theory, organic compounds were thought to exist as combinations of radicals that could be exchanged in chemical reactions just as chemical elements could be interchanged in inorganic compounds.
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The Periodic Table is a collection of short pieces, based in episodes from his life but including two short stories that he wrote before his time in Auschwitz. Each story was related in some way to one of the chemical elements. At London's Royal Institution on 19 October 2006, The Periodic Table was voted onto the shortlist for the best science book ever written.The Guardian, 21 October 2006 In 1977 at the age of 58, Levi retired as a part-time consultant at the SIVA paint factory to devote himself full-time to writing.
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If irradiated with select projectile nuclei at kinetic energies Ekin, target solid thin-film chemical elements can undergo a nuclear reaction under resonance conditions for a sharply defined resonance energy. The reaction product is usually a nucleus in an excited state which immediately decays, emitting ionizing radiation. To obtain depth information the initial kinetic energy of the projectile nucleus (which has to exceed the resonance energy) and its stopping power (energy loss per distance traveled) in the sample has to be known. To contribute to the nuclear reaction the projectile nuclei have to slow down in the sample to reach the resonance energy.
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The chemical formula for a molecule uses one line of chemical element symbols, numbers, and sometimes also other symbols, such as parentheses, dashes, brackets, and plus (+) and minus (−) signs. These are limited to one typographic line of symbols, which may include subscripts and superscripts. A compound's empirical formula is a very simple type of chemical formula. It is the simplest integer ratio of the chemical elements that constitute it. For example, water is always composed of a 2:1 ratio of hydrogen to oxygen atoms, and ethanol (ethyl alcohol) is always composed of carbon, hydrogen, and oxygen in a 2:6:1 ratio.
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Hoyle authored the first two research papers ever published on the synthesis of the chemical elements heavier than helium by nuclear reactions in stars. The first of these in 1946 showed that the cores of stars will evolve to temperatures of billions of degrees, much hotter than temperatures considered for thermonuclear origin of stellar power in main sequence stars. Hoyle showed that at such high temperatures the element iron can become much more abundant than other heavy elements owing to thermal equilibrium among nuclear particles, explaining the high natural abundance of iron. This idea would later be called the e Process.
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Worried about being misunderstood and by British libel laws, Hoyle carefully composed a letter of explanation to The Times. The second controversy came when the 1983 prize went in part to William Alfred Fowler "for his theoretical and experimental studies of the nuclear reactions of importance in the formation of the chemical elements in the universe." The controversy arose because Hoyle had been the inventor of the theory of nucleosynthesis in the stars with two research papers"The synthesis of the elements from hydrogen" MNRAS 106, 343 (1946); "The synthesis of the elements from carbon to nickel" Astrophys. J. Suppl.
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In comparison, the flux of the HFIR reactor is 5 > neutrons/(cm2·s). A dedicated laboratory was set up right at Enewetak Atoll > for preliminary analysis of debris, as some isotopes could have decayed by > the time the debris samples reached the U.S. The laboratory was receiving > samples for analysis, as soon as possible, from airplanes equipped with > paper filters which flew over the atoll after the tests. Whereas it was > hoped to discover new chemical elements heavier than fermium, those were not > found after a series of megaton explosions conducted between 1954 and 1956 > at the atoll.Seaborg, p.
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The first sector field mass spectrometer was the result of these experiments. Replica of Aston's third mass spectrometer It was speculations about isotopy that directly gave rise to the building of a mass spectrometer capable of separating the isotopes of the chemical elements. Aston initially worked on the identification of isotopes in the element neon and later chlorine and mercury. First World War stalled and delayed his research on providing experimental proof for the existence of isotopes by mass spectroscopy and during the war, Aston worked at the Royal Aircraft Establishment in Farnborough as a Technical Assistant working on aeronautical coatings.
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Cherry tree moving with the wind blowing about 22 m/sec (about 49 mph) Wind is the flow of gases on a large scale. On the surface of the Earth, wind consists of the bulk movement of air. In outer space, solar wind is the movement of gases or charged particles from the Sun through space, while planetary wind is the outgassing of light chemical elements from a planet's atmosphere into space. Winds are commonly classified by their spatial scale, their speed, the types of forces that cause them, the regions in which they occur, and their effect.
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In 1766 he published an Essay on the Management of Bees. The A New System of Practical Husbandry, (1767) treated all branches of agriculture, and contains the first mention of the potato as grown in fields. In 1770 appeared a translation from the Latin of G.A. Gyllenberg's Natural and Chemical Elements of Agriculture; in 1772 an Essay on the Weather (translated into Dutch in 1772), and Essays, Moral, Philosophical, and Political (anonymous, but advertised under his name); and in 1776 a Treatise on Cattle. On 13 February 1766List of Fellows of the Royal Society 1660 – 2007 at royalsociety.
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Friedrich Wöhler () FRS(For) HFRSE (31 July 180023 September 1882) was a German chemist, known for his work in inorganic chemistry, being the first to isolate the chemical elements beryllium and yttrium in pure metallic form. He was the first to prepare several inorganic compounds including silane and silicon nitride. Wöhler is known for seminal contributions in organic chemistry, in particular the Wöhler synthesis of urea. His synthesis of the organic compound urea in the laboratory from inorganic precursors refuted the prevailing belief that organic compounds could only be produced by living organisms due to a "life force".
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Habitat degradation and pollution are major threats to their conservation; North American river otters are highly sensitive to pollution and readily accumulate high levels of mercury, organochloride compounds, and other chemical elements. The species is often used as a bioindicator because of its position at the top of the food chain in aquatic ecosystems. Environmental disasters, such as oil spills, may increase levels of blood haptoglobin and interleukin-6 immunoreactive protein, but decrease body mass. Home ranges of North American river otters increase in size on oiled areas compared to unoiled areas, and individual otters also modify their habitat use.
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This annex contains a list of elements by atomic number, giving the names and standard symbols of the chemical elements from atomic number 1 (hydrogen, H) to 109 (unnilennium, Une). The list given in ISO 31-8:1992 was quoted from the 1998 IUPAC "Green Book" Quantities, Units and Symbols in Physical Chemistry and adds in some cases in parentheses the Latin name for information, where the standard symbol has no relation to the English name of the element. Since the 1992 edition of the standard was published, some elements with atomic number above 103 have been discovered and renamed.
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In the 1957 nuclear physics course at Caltech Clayton learned from William Alfred Fowler about a new theory that the chemical elements had been assembled within the stars by nuclear reactions occurring there. He was captivated for life by that idea. Clayton completed his Ph.D. Thesis in 1961 on the growth of the abundances of the heavy elements owing to the slow capture of free neutrons (the s process) by more abundant lighter elements in stars. Clayton and his wife Mary LouNote: Mary Lou Clayton was hired by Mathew Sands on the Ford Foundation project for these lectures.
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Edward Anders (born June 21, 1926) is a Latvian-born American chemist and emeritus professor of chemistry at the University of Chicago. His major areas of research have included the origin and ages of meteorites, the existence of presolar grains in meteorites, the solar-system abundance of chemical elements, and mass extinctions in earth history. In the 1970s, he was one of the 142 principal investigators who studied lunar samples brought back to Earth by the Apollo program. After retiring from scientific research in 1991, he became a prominent researcher, speaker and writer on issues related to the Holocaust in Latvia.
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A total of seventeen mendelevium isotopes are known, the most stable being 258Md with a half-life of 51 days; nevertheless, the shorter- lived 256Md (half-life 1.17 hours) is most commonly used in chemistry because it can be produced on a larger scale. Mendelevium was discovered by bombarding einsteinium with alpha particles in 1955, the same method still used to produce it today. It was named after Dmitri Mendeleev, father of the periodic table of the chemical elements. Using available microgram quantities of the isotope einsteinium-253, over a million mendelevium atoms may be produced each hour.
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The strength and resilience of some metals has led to their frequent use in, for example, high-rise building and bridge construction, as well as most vehicles, many home appliances, tools, pipes, and railroad tracks. Precious metals were historically used as coinage, but in the modern era, coinage metals have extended to at least 23 of the chemical elements. The history of refined metals is thought to begin with the use of copper about 11,000 years ago. Gold, silver, iron (as meteoric iron), lead, and brass were likewise in use before the first known appearance of bronze in the 5th millennium BCE.
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In southern Henan Province, Xinyang is a place with a mild climate and good conditions for growing trees that produce the tea's unique quality: Xinyang tea trees are planted at high altitudes where the weather is clearly divided by four seasons. Many high mountains, such as Mt. Cheyun, Mt. Jiyun, and Mt. Tianyun, surround the location and support environmental humidification and moisture. Moreover, the location is abundant with forests, clouds, rainfall, with large temperature difference between day and night. These geographical advantages help keep Xinyang's soil healthy and fertile, while trees more efficiently absorb chemical elements to produce higher quality green tea.
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By convention, naming rights for newly discovered chemical elements go to their discoverers. For elements 104, 105, and 106, there was a controversy between Soviet researchers at the Joint Institute for Nuclear Research and American researchers at Lawrence Berkeley National Laboratory regarding which group had discovered them first. Both parties suggested their own names for elements 104 and 105, not recognizing the other's name. The American name of seaborgium for element 106 was also objectionable to some, because it referred to American chemist Glenn T. Seaborg who was still alive at the time this name was proposed.
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Mononuclidic and monoisotopic (19 elements) Two mononuclidic, but radioactive elements (bismuth and protactinium) A mononuclidic element or monotopic element is one of the 21 chemical elements that is found naturally on Earth essentially as a single nuclide (which may, or may not, be a stable nuclide). This single nuclide will have a characteristic atomic mass. Thus, the element's natural isotopic abundance is dominated either by one stable isotope or by one very long-lived isotope. There are 19 elements in the first category (which are both monoisotopic and mononuclidic), and 2 (bismuthUntil 2003, 209Bi was thought to be in the first category.
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Alexandre-Emile Béguyer de Chancourtois Alexandre-ÉmileShaka mate \D. H. Rouvray – Endeavour, Elements in the history of the Periodic Table 2004 – Elsevier "As if on cue, only 18 months after the Karlsruhe Congress, the earliest version of the Periodic Table Émile Beguyer de Chancourtois (1819–1886) in April 1862 [19]." Béguyer de Chancourtois (20 January 1820 – 14 November 1886) was a French geologist and mineralogist who was the first to arrange the chemical elements in order of atomic weights, doing so in 1862. De Chancourtois only published his paper, but did not publish his actual graph with the irregular arrangement.
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Group 10, numbered by current IUPAC style, is the group of chemical elements in the periodic table that consists of nickel (Ni), palladium (Pd), platinum (Pt), and perhaps also the chemically uncharacterized darmstadtium (Ds). All are d-block transition metals. All known isotopes of darmstadtium are radioactive with short half-lives, and are not known to occur in nature; only minute quantities have been synthesized in laboratories. Like other groups, the members of this group show patterns in electron configuration, especially in the outermost shells, although for this group they are particularly weak, with palladium being an exceptional case.
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Mendeleev's office and library in his apartment in St. Petersburg Dmitry Mendeleev's Memorial Museum Apartment is a museum apartment of the Russian chemist Dmitry Mendeleev, who is famous for establishing the Periodic table of arranging chemical elements by their atomic masses, which allowed the prediction of properties of elements (i.e., simple substances) yet to be discovered. It is located in the Twelve Collegia building, now being the centre of Saint Petersburg State University, and in Mendeleev's time called Head Pedagogical Institute with his archives. The street in front of these is named after him as Mendeleevskaya liniya (Mendeleev Line).
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The American Academy of Achievement presented Seaborg with the Golden Plate Award in 1972. The element seaborgium was named after Seaborg by Albert Ghiorso, E. Kenneth Hulet, and others, who also credited Seaborg as a co-discoverer. It was named while Seaborg was still alive, which proved controversial. He influenced the naming of so many elements that with the announcement of seaborgium, it was noted in Discover magazine's review of the year in science that he could receive a letter addressed in chemical elements: seaborgium, lawrencium (for the Lawrence Berkeley Laboratory where he worked), berkelium, californium, americium.
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Observations show that more distant galaxies are closer together and have lower content of chemical elements heavier than lithium.:Image:CMB Timeline75.jpg – NASA (public domain image) Applying the cosmological principle, this suggests that heavier elements were not created in the Big Bang but were produced by nucleosynthesis in giant stars and expelled across a series of supernovae explosions and new star formation from the supernovae remnants, which means heavier elements would accumulate over time. Another observation is that the furthest galaxies (earlier time) are often more fragmentary, interacting and unusually shaped than local galaxies (recent time), suggesting evolution in galaxy structure as well.
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Some molecules contain one or more unpaired electrons, creating radicals. Most radicals are comparatively reactive, but some, such as nitric oxide (NO) can be stable. A 2-D structural formula of a benzene molecule (C6H6) The "inert" or noble gas elements (helium, neon, argon, krypton, xenon and radon) are composed of lone atoms as their smallest discrete unit, but the other isolated chemical elements consist of either molecules or networks of atoms bonded to each other in some way. Identifiable molecules compose familiar substances such as water, air, and many organic compounds like alcohol, sugar, gasoline, and the various pharmaceuticals.
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Ancient philosophy posited a set of classical elements to explain observed patterns in nature. These elements originally referred to earth, water, air and fire rather than the chemical elements of modern science. The term 'elements' (stoicheia) was first used by the Greek philosopher Plato in about 360 BCE in his dialogue Timaeus, which includes a discussion of the composition of inorganic and organic bodies and is a speculative treatise on chemistry. Plato believed the elements introduced a century earlier by Empedocles were composed of small polyhedral forms: tetrahedron (fire), octahedron (air), icosahedron (water), and cube (earth).
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Duncumb worked at the University of Cambridge as a research fellow from 1957 until 1959. He carried out key work on the development of the scanning electron probe X-ray microanalyser, now a common tool for surface studies in most materials laboratories. His early work led to the first commercial instrument for imaging the distribution of selected chemical elements on a microscale, providing essential information for failure analysis and the development of new materials. After joining the Central Laboratories of Tube Investments in 1959, he built a second instrument, known as EMMA, combining X-ray microanalysis with transmission electron microscopy.
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Furthermore, the Ixupi are associated with chemical elements and materials, such as sand, metal, wood or electricity, which they can inhabit. These led to the demise of the unfortunate teens, and eventually of the Professor himself. The player becomes tasked with finding a way to capture the ten spirits before the sun rises (though no actual time limit is imposed on the gameplay), and free the trapped ghosts of the Professor and the teens. This can be done by finding each vessel and its corresponding talisman/cover throughout all the museum, and where the respective Ixupi is hiding in order to trap it.
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These stars are red giants with a high metallicity (a measure of the proportion of chemical elements other than hydrogen and helium within a star) indicating an inner galactic origin, since stars outside the disks of galaxies tend to have low metallicity and are older. Some recently discovered supernovae have been confirmed to have exploded hundreds of thousands of light years from the nearest star or galaxy. Most intergalactic star candidates found in the neighborhood of the Milky Way seem not to have an origin in the Galactic Center but in the Milky Way disk or elsewhere.
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Georgius Agricola is considered the 'father of mineralogy'. Nicolas Steno founded the stratigraphy (the study of rock layers (strata) and layering (stratification)), the geology characterizes the rocks in each layer and the mineralogy characterizes the minerals in each rock. The chemical elements were discovered in identified minerals and with the help of the identified elements the mineral crystal structure could be described. One milestone was the discovery of the geometrical law of crystallization by René Just Haüy, a further development of the work by Nicolas Steno and Jean-Baptiste L. Romé de l'Isle (the characterisation of a crystalline mineral needs knowledge on crystallography).
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Nowadays, non-destructive electron microprobe analysis is used to get the empirical formula of a mineral. Finally, the International Zeolite Association (IZA) took care of the zeolite frameworks (part of molecular sieves and/or molecular cages). There are only a few thousand mineral species and 83 geochemically stable chemical elements combine to form them (84 elements, if plutonium and the Atomic Age are included). The mineral evolution in the geologic time context were discussed and summarised by Arkadii G. Zhabin (and subsequent Russian workers), Robert M. Hazen, William A. Deer, Robert A. Howie and Jack Zussman.
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Shortly after the war, she taught astronomy at ULO to undergraduate students from across the University of London system, including Arthur C. Clarke who was then an undergraduate at King's College London. In 1951 she took a position at the University of Chicago's Yerkes Observatory, Wisconsin, her first job in the United States. Her research during this period focused on the abundances of chemical elements in stars. She returned to the UK in 1953, when Margaret and her husband Geoffrey Burbidge were invited to work with William Alfred Fowler and Fred Hoyle at the University of Cambridge.
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John Marmion Edmond FRS (April 27, 1943 - April 10, 2001) was a professor of marine geochemistry and oceanography at the Massachusetts Institute of Technology, who did pioneering work on oceanic particulate matter, the oceanic carbon dioxide cycle, trace elements, and radioisotopes. He explored and analyzed water chemistry from environments as diverse as the mid-ocean ridge hydrothermal vents to the polar oceans to remote rivers and lakes in South America, Africa, Siberia, and Tibet. He and his students and colleagues in his lab measured more chemical elements at lower concentrations in water than had ever been done before.
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Clarice Evone Phelps () is an American nuclear chemist researching the processing of radioactive transuranic elements at the U.S. Department of Energy's Oak Ridge National Laboratory (ORNL). She was part of ORNL's team that collaborated with the Joint Institute for Nuclear Research to discover tennessine (element 117). The International Union of Pure and Applied Chemistry (IUPAC; which, among other responsibilities, coordinates with laboratories and the public for the naming of new chemical elements), recognizes her as the first African-American woman to be involved with the discovery of a chemical element. Phelps was formerly in the US Navy Nuclear Power Program.
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Janet started from the fact that the series of chemical elements is a continuous sequence, which he represented as a helix traced on the surfaces of four nested cylinders. By various geometrical transformations he derived several striking designs, one of which is his "left-step Periodic Table", in which hydrogen and helium are placed above lithium and beryllium. It was only later that he realized that his arrangement agreed perfectly with quantum theory and the electronic structure of the atom. He placed the actinides under the lanthanides twenty years before Glenn Seaborg, and he continued the series to element 120.
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Below Jupiter's outer atmosphere, volume fractions are significantly different from mole fractions due to high temperatures (ionization and disproportionation) and high density where the Ideal Gas Law is inapplicable. The abundance of chemical elements in the universe is dominated by the large amounts of hydrogen and helium which were produced in the Big Bang. Remaining elements, making up only about 2% of the universe, were largely produced by supernovae and certain red giant stars. Lithium, beryllium and boron are rare because although they are produced by nuclear fusion, they are then destroyed by other reactions in the stars.
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Figure 7: Plot of the cross section of different fusion reactions. Nuclear fusion refers to nuclear reactions that combine lighter nuclei to become heavier nuclei. All chemical elements can be fused; for elements with fewer protons than iron, this process changes mass into energy that can potentially be captured to provide fusion power. The probability of a fusion reaction occurring is controlled by the cross section of the fuel,"Development of the indirect drive approach to inertial confinement fusion and the target physics basis for ignition and gain" John Lindl, Physics of Plasma, 1995 which is in turn a function of its temperature.
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Furthermore, for many nuclides cross sections for nuclear reactions with thermal neutrons are quoted, usually for the (n, γ)-reaction (neutron capture), partly fission cross sections for the induced nuclear fission and cross sections for the (n, α)-reaction or (n, p)-reaction. For the chemical elements cross sections and standard atomic weights (both averaged over natural isotopic composition) are specified (the relative atomic masses partially as an interval to reflect the variability of the composition of the element's natural isotope mixture). For the nuclear fission of 235U and 239Pu with thermal neutrons, percentage isobaric chain yields of fission products are listed.
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French astronomer Pierre Janssen observed the eclipse from Guntur in Madras State, British India. It was the first total eclipse since Gustav Kirchhoff's 1859 theory that the Fraunhofer lines in the solar spectrum correspond to the emission line of the different chemical elements present in the Sun. Correspondingly, Janssen observed the eclipse with the aid of a spectroscope. He noticed a bright yellow line (λ = 587.49 nm) in the spectra of the solar prominences that could not be due to sodium as had previously been assumed, and was subsequently able to observe the same line even without the need for an eclipse.
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The alkali metals consist of the chemical elements lithium (Li), sodium (Na), potassium (K),The symbols Na and K for sodium and potassium are derived from their Latin names, natrium and kalium; these are still the origins of the names for the elements in some languages, such as German and Russian. rubidium (Rb), caesium (Cs), and francium (Fr). Together with hydrogen they constitute group 1, which lies in the s-block of the periodic table. All alkali metals have their outermost electron in an s-orbital: this shared electron configuration results in their having very similar characteristic properties.
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118 chemical elements are known to exist. All elements to element 94 are found in nature, and the remainder of the discovered elements are artificially produced, with isotopes all known to be highly radioactive with relatively short half-lives (see below). The elements in this list are ordered according to the lifetime of their most stable isotope. Of these, three elements (bismuth, thorium, and uranium) are primordial because they have half-lives long enough to still be found on the Earth, while all the others are produced either by radioactive decay or are synthesized in laboratories and nuclear reactors.
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Although relatively infrequent the use of SIMS on obsidian surface investigations has produced great progress in OHD dating. SIMS in general refers to four instrumental categories according to their operation; static, dynamic, quadrupole, and time-of-flight, TOF. In essence it is a technique with a large resolution on a plethora of chemical elements and molecular structures in an essentially non destructive manner. An approach to OHD with a completely new rationale suggests that refinement of the technique is possible in a manner which improves both its accuracy and precision and potentially expands the utility by generating reliable chronological data.
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Fleischer was the coauthor with Judith W. Frondel of a glossary of minerals bearing uranium and thorium, published in four editions in 1950, 1952, 1955 and 1967. Between 1962 and 1989 he published 14 papers on the geochemistry of the lanthanide series of chemical elements. His interest in trace elements led him to study their effect on the human body. In the Fall 1970 issue of The Mineralogical Record Fleischer proposed in Some possible new minerals not yet found that BaF2 might exist in nature, but probably not in association with the highly soluble sulfate, phosphate or carbonate phases of barium.
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The journal was established by William Hume-Rothery in 1958 as the Journal of the Less- Common Metals, focussing on the chemical elements in the rows of the periodic table for the Actinide and Lanthanide series. The lanthanides are sometimes referred to as the rare earths. The journal was not strictly limited to articles about those specific elements: it also included papers about the preparation and use of other elements and alloys. The journal developed out of an international symposium on metals and alloys above 1200°C which Hume- Rothery organized at Oxford University on September 17-18, 1958.
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Spectrometers for space missions conversely tend to be of the germanium kind. When exposed to cosmic rays (charged particles from space thought to possibly originate in supernova and active galactic nuclei), chemical elements in soils and rocks emit uniquely identifiable signatures of energy in the form of gamma rays. The gamma-ray spectrometer looks at these signatures, or energies, coming from the elements present in the target soil. 250px By measuring gamma rays coming from the target body, it is possible to calculate the abundance of various elements and how they are distributed around the planet's surface.
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Lavoisier also contributed to early ideas on composition and chemical changes by stating the radical theory, believing that radicals, which function as a single group in a chemical process, combine with oxygen in reactions. He also introduced the possibility of allotropy in chemical elements when he discovered that diamond is a crystalline form of carbon. He was also responsible for the construction of the gasometer, an expensive instrument he used at his demonstrations. While he used his gasometer exclusively for these, he also created smaller, cheaper, more practical gasometers that worked with a sufficient degree of precision that more chemists could recreate.
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Deuterium discharge tube Deuterium is frequently represented by the chemical symbol D. Since it is an isotope of hydrogen with mass number 2, it is also represented by . IUPAC allows both D and , although is preferred. A distinct chemical symbol is used for convenience because of the isotope's common use in various scientific processes. Also, its large mass difference with protium (1H) (deuterium has a mass of , compared to the mean hydrogen atomic weight of , and protium's mass of ) confers non-negligible chemical dissimilarities with protium-containing compounds, whereas the isotope weight ratios within other chemical elements are largely insignificant in this regard.
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The most games won by a team is 12 by Chrissy from Blackrod and Joe from Canterbury. Trish McGowan and Seamus Hussein have won the most money (£170,000). They won 8 times. Chrissy and Joe are second in terms of winnings, with £165,000 in 12 games, while Nat Moitt and Euan Fleming are third in terms of winnings, with £155,000 in 7 games; they also held the record for the most answers given on a single list, with 40 (for Chemical Elements), until series 7 episode 5 where Hayley and Ranjit managed to name a 52 word list (the words in Bohemian Rhapsody).
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This final burning in massive stars, called explosive nucleosynthesis or supernova nucleosynthesis, is the final epoch of stellar nucleosynthesis. A stimulus to the development of the theory of nucleosynthesis was the discovery of variations in the abundances of elements found in the universe. The need for a physical description was already inspired by the relative abundances of isotopes of the chemical elements in the solar system. Those abundances, when plotted on a graph as a function of atomic number of the element, have a jagged sawtooth shape that varies by factors of tens of millions (see history of nucleosynthesis theory).
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These chemical differences extend to a range of trace elements as well (that is, chemical elements occurring in amounts of 1000 ppm or less). In particular, trace elements associated with subduction zone (island arc) volcanics tend to be high in ophiolites, whereas trace elements that are high in ocean ridge basalts but low in subduction zone volcanics are also low in ophiolites.Metcalf, R.V. and Shervais, J.W., (2008) The crystallization order of feldspar and pyroxene (clino- and orthopyroxene) in the gabbros is reversed, and ophiolites also appear to have a multi-phase magmatic complexity on par with subduction zones.
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The name Utterby comes from the Scandinavian 'by' which means village, and is a common place name suffix in the area. The 'utter' comes from the Old English 'uttera', cognate with the modern English word 'outer', or remote, and not the modern Swedish 'utter' which means otter. Therefore, to the Vikings this was 'the remote village'. This is a common construction also seen in Itterby, one of the parishes which formed Cleethorpes, and also Ytterby in Sweden, which is relatively frequent in Scandinavia and from which derive the names of the Chemical elements Yttrium, Ytterbium, Terbium and Erbium.
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The fading is caused by condensation of carbon to soot, making the star fade in visible light while measurements in infrared light exhibit no real luminosity decrease. R Coronae Borealis variables are typically supergiant stars in the spectral classes F and G (by convention called "yellow"), with typical C2 and CN molecular bands, characteristic of yellow supergiants. RCB star atmospheres do however lack hydrogen by an abundance of 1 part per 1,000 down to 1 part per 1,000,000 relative to helium and other chemical elements, while the universal abundance of hydrogen is about 3 to 1 relative to helium.
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These processes produce most of the chemical elements in the universe heavier than zirconium (element 40), because nuclear fusion processes become increasingly inefficient and unlikely for elements heavier than this. By convention, such heavier elements produced in normal elemental abundance, are not referred to as "nucleogenic". Instead, this term is reserved for nuclides (isotopes) made on Earth from natural nuclear reactions. Also, the term "nucleogenic" by convention excludes artificially produced radionuclides, for example tritium, many of which are produced in large amounts by a similar artificial processes, but using the copious neutron flux produced by conventional nuclear reactors.
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Both of these values are slightly lower than those of barium, confirming periodic trends down the group 2 elements. Like barium and the alkali metals, radium crystallizes in the body-centered cubic structure at standard temperature and pressure: the radium–radium bond distance is 514.8 picometers. Radium has a density of 5.5 g/cm3, higher than that of barium, again confirming periodic trends; the radium-barium density ratio is comparable to the radium-barium atomic mass ratio, due to the two elements' similar crystal structures."Crystal Structures of the Chemical Elements at 1 bar" . uni-bielefeld.de.
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Partial pressure gas blending equipment for scuba diving A breathing gas is a mixture of gaseous chemical elements and compounds used for respiration. The essential component for any breathing gas is a partial pressure of oxygen of between roughly 0.16 and 1.60 bar at the ambient pressure. The oxygen is usually the only metabolically active component unless the gas is an anaesthetic mixture. Some of the oxygen in the breathing gas is consumed by the metabolic processes, and the inert components are unchanged, and serve mainly to dilute the oxygen to an appropriate concentration, and are therefore also known as diluent gases.
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Using the cyclotron, Berkeley professors and Berkeley Lab researchers went on to discover 16 chemical elements – more than any other university in the world. In particular, during World War II and following Glenn Seaborg's then-secret discovery of plutonium, Ernest Orlando Lawrence's Radiation Laboratory began to contract with the U.S. Army to develop the atomic bomb. Physics professor J. Robert Oppenheimer was named scientific head of the Manhattan Project in 1942. Along with the Lawrence Berkeley National Laboratory, Berkeley founded and was then a partner in managing two other labs, Los Alamos National Laboratory (1943) and Lawrence Livermore National Laboratory (1952).
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Administratium is a well-known in-joke in scientific circles and is a parody both on the bureaucracy of scientific establishments and on descriptions of newly discovered chemical elements. In 1991, Thomas Kyle (the supposed discoverer of this element) was awarded an Ig Nobel Prize for physics, making him one of only three fictional people to have won the award. A spoof article was written by William DeBuvitz in 1988 and first appeared in print in the January 1989 issue of The Physics Teacher. It spread rapidly among university campuses and research centers; many versions surfaced, often customized to the contributor's situation.
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Possible future for Earth due to the planetary wind: Venus The hydrodynamic wind within the upper portion of a planet's atmosphere allows light chemical elements such as hydrogen to move up to the exobase, the lower limit of the exosphere, where the gases can then reach escape velocity, entering outer space without impacting other particles of gas. This type of gas loss from a planet into space is known as planetary wind. Such a process over geologic time causes water-rich planets such as the Earth to evolve into planets like Venus. Additionally, planets with hotter lower atmospheres could accelerate the loss rate of hydrogen.
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Deep ocean minerals (DOM) are mineral nutrients (chemical elements) extracted from deep ocean water (DOW) found at ocean depths of between 250 and 1500 meters. DOW contains over 70 mineral nutrients and trace elements including magnesium (Mg), calcium (Ca) and potassium (K) in their bio ionic form. To extract these products, DOW is treated with micro filtration and reverse osmosis to desalinate and concentrate magnesium, other minerals and trace elements whilst eliminating the salt (sodium chloride). Although research about DOM is in its early stages, as it is a source of electrolytes that can help metabolize carbohydrate, proteins and fat plus maintain bone, teeth and muscle function, health benefits are possible.
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Seaborg was notified and the team left to sleep. Additional analysis and further experimentation showed the produced mendelevium isotope to have mass 256 and to decay by electron capture to fermium-256 with a half-life of 1.5 h. Being the first of the second hundred of the chemical elements, it was decided that the element would be named "mendelevium" after the Russian chemist Dmitri Mendeleev, father of the periodic table. Because this discovery came during the Cold War, Seaborg had to request permission of the government of the United States to propose that the element be named for a Russian, but it was granted.
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The solar wind had a velocity at the time of about , at which speed it would have taken eight days for the tail to be carried out to where the spacecraft was situated at 3.73 AU, approximately 45 degrees out of the ecliptic plane. The orientation of the ion tail inferred from the magnetic field measurements agreed with the source lying in Comet Hyakutake's orbital plane. The other team, working on data from the spacecraft's ion composition spectrometer, discovered a sudden large spike in detected levels of ionised particles at the same time. The relative abundances of chemical elements detected indicated that the object responsible was definitely a comet.
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Magnetic sector mass spectrometer used in isotope ratio analysis, through thermal ionization Isotope analysis is the identification of isotopic signature, the abundance of certain stable isotopes and chemical elements within organic and inorganic compounds. Isotopic analysis can be used to understand the flow of energy through a food web, to reconstruct past environmental and climatic conditions, to investigate human and animal diets in the past, for food authentification, and a variety of other physical, geological, palaeontological and chemical processes. Stable isotope ratios are measured using mass spectrometry, which separates the different isotopes of an element on the basis of their mass-to-charge ratio.
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The Mystery of Matter: Search for the Elements is a 2014 American documentary film, which premiered nationwide on August 19, 2015. The PBS film, in three- episodes of one hour each, was directed by Stephen Lyons and Muffie Meyer. The film, which took ten years to make, describes the search for the basic chemical elements that form matter by focusing on the lives and times of seven scientific visionaries. Hosted by actor Michael Emerson, the film depicts the creative process of the scientists, with actors describing the process of discovery in the scientists' own words and reenacting their major discoveries using replicas of their original laboratory equipment.
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In January 2011, Muller created the educational science channel Veritasium on YouTube, the focus of which is "addressing counter-intuitive concepts in science, usually beginning by discussing ideas with members of the public". The videos range in style from interviews with experts, such as 2011 Physics Nobel Laureate Brian Schmidt, to science experiments, dramatisations, songs, and—a hallmark of the channel—interviews with the public to uncover misconceptions about science. The name Veritasium is a combination of the Latin word for truth, Veritas, and the suffix common to many elements, -ium. This creates Veritasium, an "element of truth", a play on the popular phrase and a reference to chemical elements.
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Chemical elements may also be categorized by their origin on Earth, with the first 94 considered naturally occurring, while those with atomic numbers beyond 94 have only been produced artificially as the synthetic products of man-made nuclear reactions. Of the 94 naturally occurring elements, 83 are considered primordial and either stable or weakly radioactive. The remaining 11 naturally occurring elements possess half lives too short for them to have been present at the beginning of the Solar System, and are therefore considered transient elements. Of these 11 transient elements, 5 (polonium, radon, radium, actinium, and protactinium) are relatively common decay products of thorium and uranium.
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In 1661, Robert Boyle proposed his theory of corpuscularism which favoured the analysis of matter as constituted by irreducible units of matter (atoms) and, choosing to side with neither Aristotle's view of the four elements nor Paracelsus' view of three fundamental elements, left open the question of the number of elements. The first modern list of chemical elements was given in Antoine Lavoisier's 1789 Elements of Chemistry, which contained thirty-three elements, including light and caloric. By 1818, Jöns Jakob Berzelius had determined atomic weights for forty-five of the forty-nine then-accepted elements. Dmitri Mendeleev had sixty-six elements in his periodic table of 1869.
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The white dwarf cannot be seen directly, but is estimated to have an apparent magnitude of 13.2. Zeta Cygni has an overabundance of barium, as well as other heavy chemical elements in its atmosphere, making it a so-called "mild" barium star. These elements were synthesized by the other member of the system as it passed through the asymptotic giant branch (AGB) stage of its evolution, then ejected in its stellar wind and accreted onto the current primary component. Prior to acquiring this additional mass, Zeta Cygni had about 2.5 times the mass of the Sun, while the more evolved AGB star had three solar masses.
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2016: current form, 118 known elements The periodic table is an arrangement of the chemical elements, organized on the basis of their atomic numbers, electron configurations and recurring chemical properties. Elements are presented in order of increasing atomic number. The standard form of the table consists of a grid with rows called periods and columns called groups. The history of the periodic table reflects over two centuries of growth in the understanding of the chemical and physical properties of the elements, with major contributions made by Antoine-Laurent de Lavoisier, Johann Wolfgang Döbereiner, John Newlands, Julius Lothar Meyer, Dmitri Mendeleev, Glenn T. Seaborg, and others.
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Dr. Hall is the only scientist authorized to disarm the automatic self-destruct mechanism; he is an unmarried male and thus presumed to make the most dispassionate decisions during crisis. Further investigation determines that the deaths were caused by an extraterrestrial microbe transported by a meteor that crashed into the satellite, knocking it from orbit. The microbe contains chemical elements required for terrestrial life and appears to have a crystalline structure, but lacks the DNA, RNA, proteins, and amino acids present in all forms of terrestrial life, and directly transforms energy to matter with no discernible byproducts. The microbe, code named "Andromeda", mutates with each growth cycle, changing its biological properties.
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Biogeochemistry is the scientific discipline that involves the study of the chemical, physical, geological, and biological processes and reactions that govern the composition of the natural environment (including the biosphere, the cryosphere, the hydrosphere, the pedosphere, the atmosphere, and the lithosphere). In particular, biogeochemistry is the study of the cycles of chemical elements, such as carbon and nitrogen, and their interactions with and incorporation into living things transported through earth scale biological systems in space through time. The field focuses on chemical cycles which are either driven by or influence biological activity. Particular emphasis is placed on the study of carbon, nitrogen, sulfur, iron, and phosphorus cycles.
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Lemaître's model was needed to explain the existence of deuterium and nuclides between helium and carbon, as well as the fundamentally high amount of helium present, not only in stars but also in interstellar space. As it happened, both Lemaître and Hoyle's models of nucleosynthesis would be needed to explain the elemental abundances in the universe. The goal of the theory of nucleosynthesis is to explain the vastly differing abundances of the chemical elements and their several isotopes from the perspective of natural processes. The primary stimulus to the development of this theory was the shape of a plot of the abundances versus the atomic number of the elements.
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Those abundances, when plotted on a graph as a function of atomic number, have a jagged sawtooth structure that varies by factors up to ten million. A very influential stimulus to nucleosynthesis research was an abundance table created by Hans Suess and Harold Urey that was based on the unfractionated abundances of the non-volatile elements found within unevolved meteorites. Such a graph of the abundances is displayed on a logarithmic scale below, where the dramatically jagged structure is visually suppressed by the many powers of ten spanned in the vertical scale of this graph. Abundances of the chemical elements in the Solar System.
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Thus pseudoscience is a subset of un-science, and un-science, in turn, is subset of non-science. Science is also distinguishable from revelation, theology, or spirituality in that it offers insight into the physical world obtained by empirical research and testing. The most notable disputes concern the origin of life, all living and decreased organisms sharing common descent, the geological history of Earth, the formation of the solar system, origin of early chemical elements, and the origin of the universe. Systems of belief that derive from divine or inspired knowledge are not considered pseudoscience if they do not claim either to be scientific or to overturn well-established science.
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Each stardust grain existed before the Earth was formed. Stardust is a scientific term referring to refractory dust grains that condensed from cooling ejected gases from individual presolar stars and incorporated into the cloud from which the Solar System condensed.Donald D. Clayton, Precondensed Matter: Key to the Early Solar System, Moon & Planets 19, 109 (1978) Many different types of stardust have been identified by laboratory measurements of the highly unusual isotopic composition of the chemical elements that comprise each stardust grain. These refractory mineral grains may earlier have been coated with volatile compounds, but those are lost in the dissolving of meteorite matter in acids, leaving only insoluble refractory minerals.
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Accordingly, ITS-90 uses numerous defined points, all of which are based on various thermodynamic equilibrium states of fourteen pure chemical elements and one compound (water). Most of the defined points are based on a phase transition; specifically the melting/freezing point of a pure chemical element. However, the deepest cryogenic points are based exclusively on the vapor pressure/temperature relationship of helium and its isotopes whereas the remainder of its cold points (those less than room temperature) are based on triple points. Examples of other defining points are the triple point of hydrogen (−259.3467 °C) and the freezing point of aluminium (660.323 °C).
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Further, because metasomatism is a mass transfer process, it is not restricted to the rocks which are changed by addition of chemical elements and minerals or hydrous compounds. In all cases, to produce a metasomatic rock some other rock is also metasomatised, if only by dehydration reactions with minimal chemical change. This is best illustrated by gold ore deposits which are the product of focused concentration of fluids derived from many cubic kilometres of dehydrated crust into thin, often highly metasomatised and altered shear zones and lodes. The source region is often largely chemically unaffected compared to the highly hydrated, altered shear zones, but both must have undergone complementary metasomatism.
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The most stable of plastics used in photo preservation, polyester, does not generate any harmful chemical elements, but nor does it have any capability to absorb acids generated by the photograph itself. Polyester sleeves and encapsulation have been praised for their ability to protect the photograph from humidity and environmental pollution, slowing the reaction between the item and the atmosphere. This is true, however the polyester just as frequently traps these elements next to the material it is intended to protect. This is especially risky in a storage environment that experiences drastic fluctuations in humidity or temperature, leading to ferrotyping, or sticking of the photograph to the plastic.
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TU Bergakademie campus, April 2007 The Technische Universität Bergakademie Freiberg (usually translated from German as Freiberg University of Mining and Technology or Freiberg Mining Academy, University of Technology) is a German university of technology with about 4,300 students in the city of Freiberg, Saxony. It was established in 1765 by Prince Franz Xaver, regent of Saxony, based on plans by Friedrich Wilhelm von Oppel and Friedrich Anton von Heynitz, and is the oldest university of mining and metallurgy in the world. The chemical elements indium (1863) and germanium (1886) were discovered by scientists of Freiberg University. The polymath Alexander von Humboldt studied mining at the Bergakademie from 1791 to 1792.
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The noble gases (historically also the inert gases; sometimes referred to as aerogens) make up a class of chemical elements with similar properties; under standard conditions, they are all odorless, colorless, monatomic gases with very low chemical reactivity. The six naturally occurring noble gases are helium (He), neon (Ne), argon (Ar), krypton (Kr), xenon (Xe), and the radioactive radon (Rn). Oganesson (Og) is variously predicted to be a noble gas as well or to break the trend due to relativistic effects; its chemistry has not yet been investigated. For the first six periods of the periodic table, the noble gases are exactly the members of group 18\.
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The chirp mass, a directly observable parameter which may be very roughly equated to the geometric mean of the masses, is measured at . The neutron star merger event is thought to result in a kilonova, characterized by a short gamma-ray burst followed by a longer optical "afterglow" powered by the radioactive decay of heavy r-process nuclei. Kilonovae are candidates for the production of half the chemical elements heavier than iron in the Universe. A total of 16,000 times the mass of the Earth in heavy elements is believed to have formed, including approximately 10 Earth masses just of the two elements gold and platinum.
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They trace the epicenter of the pending disaster to an area beneath the Carlsbad Caverns and descend to a hitherto unexplored level. Here they find a strange ore which, when removed from contact with water, becomes highly explosive, and realize that this element, somehow working its way from deep in the Earth, is responsible for the earthquakes. Although the material is not analyzed for specific atomic traits, it is named Element 112 just because so far, 111 chemical elements had been discovered. A computer determines that in approximately one month, enough of Element 112 will emerge from the deep earth to cause the entire planet to explode.
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A notable exception is "The Elements", in which he set the names of the chemical elements to the tune of the "Major-General's Song" from Gilbert and Sullivan's Pirates of Penzance. Lehrer's early musical work typically dealt with non- topical subject matter and was noted for its black humor in songs such as "Poisoning Pigeons in the Park". In the 1960s, he produced a number of songs that dealt with social and political issues of the day, particularly when he wrote for the U.S. version of the television show That Was the Week That Was. The popularity of these songs has far outlasted their topical subjects and references.
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The Chinese Chemical Society (CCS; ) lays out a set of rules based on those given by the International Union of Pure and Applied Chemistry (IUPAC) for the purpose of systematic organic nomenclature in Chinese. The chemical names derived from these rules are meant to correspond with the English IUPAC name in a manner that is close to one-to-one, while being adapted to and taking advantage of the logographic nature of the Chinese written language. A standard set of characters invented during the 20th century (vide infra), along with characters for the chemical elements and characters corresponding to standard chemical prefixes and suffixes, are used for this purpose.
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Hinrichs is one of the discoverers of the periodic laws, which are the basis for the periodic table of elements. Although his contribution is not generally considered as important as those of Dmitri Mendeleev or Lothar Meyer, he presented his ideas as early as 1855 and published his book Programme der Atommechanik in 1867. His periodic table had the form of a spiral, and the elements were placed into the structure according to their atomic mass. Hinrichs also postulated a theory on the cause of the periodicity within the chemical elements based on his theory of the composition of elements out of smaller Panatome.
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The remaining 4.9% comprises all ordinary matter observed as atoms, chemical elements, gas and plasma, the stuff of which visible planets, stars and galaxies are made. The great majority of ordinary matter in the universe is unseen, since visible stars and gas inside galaxies and clusters account for less than 10% of the ordinary matter contribution to the mass-energy density of the universe. Also, the energy density includes a very small fraction (~ 0.01%) in cosmic microwave background radiation, and not more than 0.5% in relic neutrinos. Although very small today, these were much more important in the distant past, dominating the matter at redshift > 3200.
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In chemistry, a retained name is a name for a chemical compound that is recommended for use by a system of chemical nomenclature (for example, IUPAC nomenclature), but that is not fully systematic. Retained names are often used for the most fundamental parts of a nomenclature system: almost all the chemical elements have retained names rather than being named systematically, as do the first four alkanes, benzene and most simple heterocyclic compounds. Water and ammonia are other examples of retained names. Retained names may be either semisystematic or completely trivial; that is, they may contain certain elements of systematic nomenclature or none at all.
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The "Arecibo answer" is a hoax by people that created an imprint in a crop field (crop circle) in 2001 near the Chilbolton radio telescope in Hampshire, UK, portrayed as a response from an extraterrestrial civilization. The crop circle is a near replica of the Arecibo message. The feature forms the same 23 × 73 grid because these numbers are primes and most of the chemical data remains the same with the exception that in the section detailing important chemical elements, the main focus is altered from carbon to silicon, and the diagram of DNA has been rewritten. At the bottom, the pictogram of a human is replaced with a shorter figure with a large, bulbous head.
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He used of some of the first computers in Canada, originally purchased for use by the accounting department at the laboratory, to do the calculations. At first, he was able to give programs on trays of punch cards to the accountants to run on his behalf. However, as his calculations increased in sophistication and the computing resources at Chalk River improved, he switched to work during the night and on weekends when the machines were not in use. In 1957, he published Nuclear Reactions in Stars and Nucleogenesis, known as the AGWC paper, which introduced an important, early, comprehensive theory of the production of chemical elements in stars, especially r-process elements.
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Donald D. Clayton in 2012 Donald Delbert Clayton (born March 18, 1935) is an American astrophysicist whose most visible achievement was the prediction from nucleosynthesis theory that supernovae are intensely radioactive. That earned Clayton the NASA Exceptional Scientific Achievement Medal (1992) for “theoretical astrophysics related to the formation of (chemical) elements in the explosions of stars and to the observable products of these explosions”. Supernovae thereafter became the most important stellar events in astronomy owing to their profoundly radioactive nature. Not only did Clayton discover radioactive nucleosynthesis during explosive silicon burning in stars ["Nucleosynthesis During Silicon Burning", D. Bodansky. D.D, Clayton & W.A. Fowler, Physical Review Letters, 20, 161, (1968); “Nuclear quasi-equilibrium during silicon burning”, D. Bodansky.
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To do this, however, Redcloak needed the cooperation of an arcane caster, recruiting Xykon. Intelligent, with a dry and somewhat sarcastic sense of humour, Redcloak usually plays the straight man to the rest of his team's antics. He appears to have a decent grasp of tactics and considers them more important than does his master. He is familiar with chemistry to the extent that he can summon elementals based on specific chemical elements, such as titanium and chlorine during the siege of Azure City, osmium when taking control of the resistance HQ, magnesium during a bonus comic, and silicon while in the desert, rather than the classical elements of Earth, Air, Water and Fire.
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Chemical compounds can be molecular compounds held together by covalent bonds, salts held together by ionic bonds, intermetallic compounds held together by metallic bonds, or the subset of chemical complexes that are held together by coordinate covalent bonds. Pure chemical elements are generally not considered chemical compounds, failing the two or more atom requirement, though they often consist of molecules composed of multiple atoms (such as in the diatomic molecule H2, or the polyatomic molecule S8, etc.). Many chemical compounds have a unique numerical identifier assigned by the Chemical Abstracts Service (CAS): its CAS number. There is varying and sometimes inconsistent nomenclature differentiating substances, which include truly non-stoichiometric examples, from chemical compounds, which require the fixed ratios.
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Photographic recording of the characteristic X-ray emission lines of some elements In his report on The Periodic Law of the Chemical Elements, in 1869, Dmitri Mendeleev had implicitly predicted the existence of a heavier analog of titanium and zirconium. At the time of his formulation in 1871, Mendeleev believed that the elements were ordered by their atomic masses and placed lanthanum (element 57) in the spot below zirconium. The exact placement of the elements and the location of missing elements was done by determining the specific weight of the elements and comparing the chemical and physical properties. The X-ray spectroscopy done by Henry Moseley in 1914 showed a direct dependency between spectral line and effective nuclear charge.
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Heike Kamerlingh Onnes and Johannes van der Waals with the helium liquefactor at Leiden in 1908 One of the first studies of condensed states of matter was by English chemist Humphry Davy, in the first decades of the nineteenth century. Davy observed that of the forty chemical elements known at the time, twenty-six had metallic properties such as lustre, ductility and high electrical and thermal conductivity. This indicated that the atoms in John Dalton's atomic theory were not indivisible as Dalton claimed, but had inner structure. Davy further claimed that elements that were then believed to be gases, such as nitrogen and hydrogen could be liquefied under the right conditions and would then behave as metals.
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The outer shell of dark, opaque, hot cloud is assumed to consist of vanadium and titanium oxides, but other compounds like tholins cannot be ruled out yet. The chemical elements in the atmosphere can be studied by finding their absorption lines in the thermal spectrum of the planet; given typical planet temperatures, the spectrum has its peak at infrared wavelengths. So far, only water vapor has been detected in this planet, while carbon monoxide and methane are still under the detection limit. The planet is unlikely to have large moons, since tidal forces would either eject them from orbit or destroy them on short timescales compared to the age of the system.
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The history of the discovery and use of the elements began with primitive human societies that discovered native minerals like carbon, sulfur, copper and gold (though the concept of a chemical element was not yet understood). Attempts to classify materials such as these resulted in the concepts of classical elements, alchemy, and various similar theories throughout human history. Much of the modern understanding of elements is attributed to Dmitri Mendeleev, a Russian chemist who published the first recognizable periodic table in 1869. The properties of the chemical elements are summarized in this table, which organizes them by increasing atomic number into rows ("periods") in which the columns ("groups") share recurring ("periodic") physical and chemical properties.
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The properties of the chemical elements are often summarized using the periodic table, which powerfully and elegantly organizes the elements by increasing atomic number into rows ("periods") in which the columns ("groups") share recurring ("periodic") physical and chemical properties. The current standard table contains 118 confirmed elements as of 2019. Although earlier precursors to this presentation exist, its invention is generally credited to the Russian chemist Dmitri Mendeleev in 1869, who intended the table to illustrate recurring trends in the properties of the elements. The layout of the table has been refined and extended over time as new elements have been discovered and new theoretical models have been developed to explain chemical behavior.
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Previous to this burst, there had not yet been any concrete evidence linking gamma-ray bursts to supernovae, though it had long been hypothesized that the two phenomena were results of the same type of event. The spectrum of GRB 011211 was reported to include emission lines associated with the chemical elements magnesium, silicon, sulphur, argon, and calcium, which supported the theory that gamma-ray bursts are preceded by highly massive stars undergoing a supernova collapse. However, these results were considered statistically insignificant and somewhat controversial due to the low resolution of the instruments used. The spectrum of GRB 020813 was also found to display emission lines of elements associated with supernovae, in this case sulphur and silicon.
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In physical cosmology, the Alpher–Bethe–Gamow paper, or αβγ paper, was created by Ralph Alpher, then a physics PhD student, and his advisor George Gamow. The work, which would become the subject of Alpher's PhD dissertation, argued that the Big Bang would create hydrogen, helium and heavier elements in the correct proportions to explain their abundance in the early universe. While the original theory neglected a number of processes important to the formation of heavy elements, subsequent developments showed that Big Bang nucleosynthesis is consistent with the observed constraints on all primordial elements. Formally titled "The Origin of Chemical Elements", it was published in the April 1948 issue of Physical Review.
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The change of the external environment and the wrong production process are also the reasons of wine flavour defects. The lack of wine is due to the turn of the external environment caused by the chemical changes in the composition of the wine, such as the poor sanitary conditions of the winery, dirty wine, excessive use and oak cork rot, and the influence of temperature fluctuations of the wine flavour defects. Different from the flavour defect of wine, in the brewing process of beer, the concentration of inorganic chemical elements is too high due to improper production, or the malting of malt and hops in the brewing process causes microbial deterioration, which leads to the loss of beer flavour.
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The coinage metals comprise, at a minimum, those metallic chemical elements which have historically been used as components in alloys used to mint coins. The term is not perfectly defined, however, since a number of metals have been used to make "demonstration coins" which have never been used to make monetized coins for any nation-state, but could be. Some of these elements would make excellent coins in theory (for example, zirconium), but their status as coin metals is not clear. In general, because of problems caused when coin metals are intrinsically valuable as commodities, there has been a trend in the 21st century toward use of coinage metals of only the least exotic and expensive types.
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BPS CS22892-0052 (Sneden's Star) is an old population II star located at a distance of 4.7 kpc in the galactic halo. It belongs to a class of ultra- metal-poor stars (Metallicity [Fe/H]=-3.1), specifically the very rare subclass of neutron-capture (r-process) enhanced stars. It was discovered by Tim C. Beers and collaborators with the Curtis Schmidt telescope at the Cerro Tololo Inter-American Observatory in Chile. Extended high-resolution spectroscopic observations since around 1995 (with Chris Sneden from the University of Texas at Austin as the leading observer) allowed observers to determine the abundances of 53 chemical elements in this star, as of December 2005 only second in number to the Sun.
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During the total solar eclipse of 7 August 1869, a green emission line of wavelength 530.3 nm was independently observed by Charles Augustus Young (1834–1908) and William Harkness (1837–1903) in the coronal spectrum. Since this line did not correspond to that of any known material, it was proposed that it was due to an unknown element, provisionally named coronium. In 1902, in an attempt at a chemical conception of the aether, the Russian chemist and chemical educator Dmitri Mendeleev hypothesized that there existed two inert chemical elements of lesser atomic weight than hydrogen. Of these two, he thought the lighter to be an all-penetrating, all-pervasive gas, and the slightly heavier one to be coronium.
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Diamond and graphite are two allotropes of carbon: pure forms of the same element that differ in crystalline structure. Allotropy or allotropism () is the property of some chemical elements to exist in two or more different forms, in the same physical state, known as allotropes of the elements. Allotropes are different structural modifications of an element; the atoms of the element are bonded together in a different manner. For example, the allotropes of carbon include diamond (the carbon atoms are bonded together in a tetrahedral lattice arrangement), graphite (the carbon atoms are bonded together in sheets of a hexagonal lattice), graphene (single sheets of graphite), and fullerenes (the carbon atoms are bonded together in spherical, tubular, or ellipsoidal formations).
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Near the end of the 18th century, two laws about chemical reactions emerged without referring to the notion of an atomic theory. The first was the law of conservation of mass, closely associated with the work of Antoine Lavoisier, which states that the total mass in a chemical reaction remains constant (that is, the reactants have the same mass as the products). The second was the law of definite proportions. First established by the French chemist Joseph Proust in 1797 this law states that if a compound is broken down into its constituent chemical elements, then the masses of the constituents will always have the same proportions by weight, regardless of the quantity or source of the original substance.
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European Union, City Audits: Darmstadt holds the official title "City of Science" () as it is a major centre of scientific institutions, universities, and high-technology companies. The European Organisation for the Exploitation of Meteorological Satellites (EUMETSAT) and the European Space Operations Centre (ESOC) are located in Darmstadt, as well as GSI Centre for Heavy Ion Research, where several chemical elements such as bohrium (1981), meitnerium (1982), hassium (1984), darmstadtium (1994), roentgenium (1994), and copernicium (1996) were discovered. The existence of the following elements were also confirmed at GSI Centre for Heavy Ion Research: nihonium (2012), flerovium (2009), moscovium (2012), livermorium (2010), and tennessine (2012). The Facility for Antiproton and Ion Research (FAIR) is an international accelerator facility under construction.
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For the density of the observable universe of about 4.6×10−28 kg/m3 and given the known abundance of the chemical elements, the corresponding maximal radiation energy density of 9.2×10−31 kg/m3, i.e. temperature 3.2 K (matching the value observed for the optical radiation temperature by Arthur Eddington). This is close to the summed energy density of the cosmic microwave background (CMB) and the cosmic neutrino background. The Big Bang hypothesis predicts that the CBR should have the same energy density as the binding energy density of the primordial helium, which is much greater than the binding energy density of the non-primordial elements; so it gives almost the same result.
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The Commission on Isotopic Abundances and Atomic Weights (CIAAW) is an international scientific committee of the International Union of Pure and Applied Chemistry (IUPAC) under its Division of Inorganic Chemistry. Since 1899, it is entrusted with periodic critical evaluation of atomic weights of chemical elements and other cognate data, such as the isotopic composition of elements. The biennial CIAAW Standard Atomic Weights are accepted as the authoritative source in science and appear worldwide on the periodic table wall charts. The use of CIAAW Standard Atomic Weights is also required legally, for example, in calculation of calorific value of natural gas (ISO 6976:1995), or in gravimetric preparation of primary reference standards in gas analysis (ISO 6142:2006).
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In his Faraday Memorial Lecture in 1881, the German Hermann von Helmholtz asserted that Faraday's laws of electrochemistry hinted at the atomic structure of matter. If the chemical elements were distinguishable from one another by simple ratios of mass, and if the same amounts of electricity deposited amounts of these elements upon the poles in ratios, then electricity must also come in as discrete units, later named electrons. In the late nineteenth century, the nature of the energy emitted by the discharge between high-voltage electrodes inside an evacuated tube—cathode rays—attracted the attention of many physicists. While the Germans thought cathode rays were waves, the British and the French believed they were particles.
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Between 1917 and 1922, it became clear from work by Heber Curtis, Ernst Öpik and others, that some objects ("nebulae") seen by astronomers were in fact distant galaxies like our own. But when radio astronomy commenced in the 1950s, astronomers detected, among the galaxies, a small number of anomalous objects with properties that defied explanation. The objects emitted large amounts of radiation of many frequencies, but no source could be located optically, or in some cases only a faint and point-like object somewhat like a distant star. The spectral lines of these objects, which identify the chemical elements of which the object is composed, were also extremely strange and defied explanation.
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Like other stars in its class, it is slightly variable with a range in brightness of 0.06 magnitude, and is listed as a Delta Scuti variable. Alderamin has a very high rotation speed of at least 246 km/s, completing one complete revolution in less than 12 hours, with such a rapid turnover appearing to inhibit the differentiation of chemical elements usually seen in such stars. By comparison, the Sun takes almost a month to turn on its axis. Alpha Cephei is also known to emit an amount of X radiation similar to the Sun, which along with other indicators suggests the existence of considerable magnetic activity—something unexpected (though not at all unusual) for a fast rotator.
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Periodic Tales: A Cultural History of the Elements, from Arsenic to Zinc is a 2011 popular science and history book by English writer Hugh Aldersey- Williams, on the history and cultural associations of the chemical elements. The book is divided into five sections, "Power", "Fire", "Craft", "Beauty", and "Earth", which group elements according to their primary cultural connotations, rather than their position on the periodic table. For certain elements such as phosphorus, the author documents his attempts to obtain samples by reproducing the original method of discovery. He also visits the site of discovery of several elements uncovered in modern times, including the famed Ytterby mine in Sweden, from which seven new elements were isolated.
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For the youngest pupils, about ages 5–9, the educational goal is utilitarian: batteries are devices that can power other devices, so as long as they are connected by a conductive material. Batteries are components in electrical circuits; hooking a single wire between a battery and a light bulb will not power the bulb. For children in the age range 10−13, batteries are used to illustrate the connection between chemistry and electricity as well as to deepen the circuit concept for electricity. The fact that different chemical elements such as copper and zinc are used can be placed in the larger context that the elements do not disappear or break down when they undergo chemical reactions.
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There is still no direct evidence about the composition of the inner core. However, based on the relative prevalence of various chemical elements in the Solar System, the theory of planetary formation, and constraints imposed or implied by the chemistry of the rest of the Earth's volume, the inner core is believed to consist primarily of an iron–nickel alloy. At the known pressures and estimated temperatures of the core, it is predicted that pure iron could be solid, but its density would exceed the known density of the core by approximately 3%. That result implies the presence of lighter elements in the core, such as silicon, oxygen, or sulfur, in addition to the probable presence of nickel.
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Presl had invented Czech neologisms for most of the then known chemical elements; ten of these, including vodík - hydrogen, kyslík - oxygen, uhlík - carbon, dusík - nitrogen and křemík - silicon, have entered the language. Presl also created naming conventions for oxides where the electronegative component of the compound became the noun, and the electropositive component became an adjective. The adjectives were associated with a suffix, according to the valence number of the component they represented (originally there were five suffices: -ný, -natý, -itý, -ový, -elý, later expanded to eight by Vojtěch Šafařík: -ný, -natý, -itý, -ičitý, -ičný and -ečný, -ový, -istý, -ičelý, representing oxidation numbers from 1 to 8). For example železnatý corresponds to "ferrous" and železitý to "ferric".
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Several changes were applied to the basic terminology during the second half of the 20th century, usually moving closer to the international nomenclature: for example, the former term kysličník was officially replaced by oxid (oxide), uhlovodan by sacharid and later even karbohydrát (carbohydrate) and the spelling of some chemical elements changed; and berylium should be now written beryllium. Adoption of these changes by the Czech public has been quite slow, and the older terms are still used decades later. Czechoslovak Academy of Sciences (founded in 1953) took over responsibility for the maintenance of the nomenclature, and proper implementation of the IUPAC recommendations. Since the Velvet Revolution (1989) this activity has slowed down considerably.
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A classic example of the predictive power of a theory is the discovery of Neptune as a result of predictions made by mathematicians John Couch Adams and Urbain Le Verrier, based on Newton's theory of gravity. Another example of the predictive power of theories or models is Dmitri Mendeleev's use of his periodic table to predict previously undiscovered chemical elements and their properties. Though largely correct, he misjudged the relative atomic masses of tellurium and iodine. Moreover, Charles Darwin used his knowledge of evolution by natural selection to predict that since a plant (Angraecum sesquipedale) with a long spur in its flowers exists, a complementary animal with a 30 cm proboscis must also exist to feed on and pollinate it.
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He attributed those elements to specific nuclear fusion reactions between abundant constituents in concentric shells of evolved massive, pre-supernova stars. This startlingly modern picture is the accepted paradigm today for the supernova nucleosynthesis of these primary elements. In the mid 1950s, Hoyle became the leader of a group of very talented experimental and theoretical physicists who met in Cambridge: William Alfred Fowler, Margaret Burbidge, and Geoffrey Burbidge. This group systematized basic ideas of how all the chemical elements in our universe were created, with this now being a field called nucleosynthesis. Famously, in 1957, this group produced the B2FH paper (known for the initials of the four authors) in which the field of nucleosynthesis was organized into complementary nuclear processes.
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Ulf S. von Euler was born in Stockholm, the son of two noted scientists, Hans von Euler-Chelpin, a professor of chemistry, and Astrid Cleve, a professor of botany and geology. His father was German and the recipient of Nobel Prize for Chemistry in 1929, and his maternal grandfather was Per Teodor Cleve, Professor of Chemistry at the Uppsala University, and the discoverer of the chemical elements thulium and holmium. Enjoying such a privileged family environment in science, education and research, it is not surprising that young Ulf would become a scientist, too, so he went to study medicine at the Karolinska Institute in 1922. At Karolinska, he worked under Robin Fåhraeus in blood sedimentation and rheology and did research work on the pathophysiology of vasoconstriction.
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The periodic trends are based on the Periodic Law, which states that if the chemical elements are listed in order of increasing atomic number, many of their properties go through cyclical changes, with elements of similar properties recurring at intervals. For example, after arranging elements in their increasing atomic numbers, many of the physical and chemical properties of Lithium, such as its vigorous reactivity with water, recur in sodium, potassium and caesium. This principle was discovered by Russian chemist Dmitri Mendeleev in 1871 after a number of investigations by scientists in the 19th century. Mendeleev also proposed a periodic system of elements that was based not only on atomic weights but also on chemical and physical properties of the elements and their compounds.
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"Uncleftish Beholding" (1989) is a short text by Poul Anderson designed to illustrate what English might look like without its large number of loanwords from languages such as French, Greek, and Latin. Written with the linguistic purism in English, the work explains atomic theory using Germanic words almost exclusively and coining new words when necessary; many of these new words have cognates in modern German, an important scientific language in its own right. The title phrase uncleftish beholding calques "atomic theory." To illustrate, the text begins: It goes on to define firststuffs (chemical elements), such as waterstuff (hydrogen), sourstuff (oxygen), and ymirstuff (uranium), as well as bulkbits (molecules), bindings (compounds), and several other terms important to uncleftish worldken (atomic science).
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The production of gold from a more common element, such as lead, has long been a subject of human inquiry, and the ancient and medieval discipline of alchemy often focused on it; however, the transmutation of the chemical elements did not become possible until the understanding of nuclear physics in the 20th century. The first synthesis of gold was conducted by Japanese physicist Hantaro Nagaoka, who synthesized gold from mercury in 1924 by neutron bombardment. An American team, working without knowledge of Nagaoka's prior study, conducted the same experiment in 1941, achieving the same result and showing that the isotopes of gold produced by it were all radioactive. Gold can currently be manufactured in a nuclear reactor by irradiation either of platinum or mercury.
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The masses of the two pre-merger black holes provide information about stellar evolution. Both black holes were more massive than previously discovered stellar-mass black holes, which were inferred from X-ray binary observations. This implies that the stellar winds from their progenitor stars must have been relatively weak, and therefore that the metallicity (mass fraction of chemical elements heavier than hydrogen and helium) must have been less than about half the solar value. The fact that the pre-merger black holes were present in a binary star system, as well as the fact that the system was compact enough to merge within the age of the universe, constrains either binary star evolution or dynamical formation scenarios, depending on how the black hole binary was formed.
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During his lifetime, Seaborg is said to have been the author or co-author of numerous books and 500 scientific journal articles, many of them brief reports on fast-breaking discoveries in nuclear science while other subjects, most notably the actinide concept, represented major theoretical contributions in the history of science. He held more than 40 patents—among them the only patents ever issued for chemical elements, americium and curium, and received more than 50 doctorates and honorary degrees in his lifetime. At one time, he was listed in the Guinness Book of World Records as having the longest entry in Marquis Who's Who in America. In February 2005, he was posthumously inducted into the National Inventors Hall of Fame.
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Analytical studies, performed on the rock by the Curiosity rover in October 2012, suggest the Jake M rock is an igneous rock but found to be high in elements consistent with feldspar, such as sodium, aluminum and potassium, and lower concentrations of magnesium, iron and nickel than other such rocks previously found on Mars. The mineral content and elemental abundance indicates Jake M rock may be a mugearite, a sodium rich oligoclase-bearing basaltic trachyandesite. Igneous rocks similar to the Jake M rock are well known but occur rarely on Earth. On Earth, such rocks form when magma, usually found in volcanoes, rises to the surface, cools and partially solidifies with certain chemical elements, while the warmer liquid magma portion becomes enriched with the left-behind elements.
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Potash is primarily a mixture of potassium salts because plants have little or no sodium content, and the rest of a plant's major mineral content consists of calcium salts of relatively low solubility in water. While potash has been used since ancient times, its composition was not understood. Georg Ernst Stahl obtained experimental evidence that led him to suggest the fundamental difference of sodium and potassium salts in 1702, and Henri Louis Duhamel du Monceau was able to prove this difference in 1736. The exact chemical composition of potassium and sodium compounds, and the status as chemical element of potassium and sodium, was not known then, and thus Antoine Lavoisier did not include the alkali in his list of chemical elements in 1789.
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The estimate also restricts the chemical elements used to be Carbon, Hydrogen, Oxygen, Nitrogen and Sulfur. It further makes the assumption of a maximum of 30 atoms to stay below 500 Daltons, allows for branching and a maximum of 4 rings and arrives at an estimate of 1063. This number is often misquoted in subsequent publications to be the estimated size of the whole organic chemistry space, which would be much larger if including the halogens and other elements. In addition to the drug-like space and lead- like space that are, in part, defined by the Lipinski's rule of five, the concept of known drug space (KDS), which is defined by the molecular descriptors of marketed drugs, has also been introduced.
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His original system consisted of seven elements, which included the five classical elements (aether, air, earth, fire, and water) in addition to two chemical elements representing the metals: sulphur, "the stone which burns", which characterized the principle of combustibility, and mercury, which contained the idealized principle of metallic properties. Shortly thereafter, this evolved into eight elements, with the Arabic concept of the three metallic principles: sulphur giving flammability or combustion, mercury giving volatility and stability, and salt giving solidity.Strathern, Paul. (2000), Mendeleyev's Dream – the Quest for the Elements, New York: Berkley Books The atomic theory of corpuscularianism, where all physical bodies possess an inner and outer layer of minute particles or corpuscles, also has its origins in the work of Jabir.
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The names for chemical elements in East Asian languages, along with those for some chemical compounds (mostly organic), are among the newest words to enter the local vocabularies. Except for those metals well-known since antiquity, the names of most elements were created after modern chemistry was introduced to East Asia in the 18th and 19th century, with more translations being coined for those elements discovered later. While most East Asian languages use—or have used—the Chinese script, only the Chinese language uses the characters as the predominant way of naming elements. On the other hand, the Japanese, Koreans and Vietnamese primarily employ native writing systems for the names of the elements, such as Katakana, Hangul and Quốc Ngữ, respectively.
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Their challenge was that the tools had not yet been invented with which to prove these assertions. For much of the nineteenth century, astronomical research was focused on the routine work of measuring the positions and computing the motions of astronomical objects. A new astronomy, soon to be called astrophysics, began to emerge when William Hyde Wollaston and Joseph von Fraunhofer independently discovered that, when decomposing the light from the Sun, a multitude of dark lines (regions where there was less or no light) were observed in the spectrum. By 1860 the physicist, Gustav Kirchhoff, and the chemist, Robert Bunsen, had demonstrated that the dark lines in the solar spectrum corresponded to bright lines in the spectra of known gases, specific lines corresponding to unique chemical elements.
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Flame atomic absorption spectroscopy instrument A scientist preparing solutions for atomic absorption spectroscopy, reflected in the glass window of the AAS's flame atomizer cover door Atomic absorption spectroscopy (AAS) and atomic emission spectroscopy (AES) is a spectroanalytical procedure for the quantitative determination of chemical elements using the absorption of optical radiation (light) by free atoms in the gaseous state. Atomic absorption spectroscopy is based on absorption of light by free metallic ions. In analytical chemistry the technique is used for determining the concentration of a particular element (the analyte) in a sample to be analyzed. AAS can be used to determine over 70 different elements in solution, or directly in solid samples via electrothermal vaporization, and is used in pharmacology, biophysics, archaeology and toxicology research.
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During World War II, Huizenga supervised teams at the Manhattan Project in Oak Ridge, Tenn., involved in enriching uranium used in the atomic weapon dropped on Hiroshima in August 1945. During his Argonne years, as a result of examining debris from the "Ivy Mike" nuclear test in 1952, Huizenga was part of the team that added two new synthetic chemical elements, einsteinium and fermium, to the periodic table. Google Books Google Books Huizenga and his colleagues were at first unable to publish papers on their discoveries in the open literature, because of classification concerns relating to the nuclear test, but these concerns were eventually resolved and the team was able to publish in Physical Review and thus claim priority for their discovery.
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Classical physics is generally concerned with matter and energy on the normal scale of observation, while much of modern physics is concerned with the behavior of matter and energy under extreme conditions or on a very large or very small scale. For example, atomic and nuclear physics studies matter on the smallest scale at which chemical elements can be identified. The physics of elementary particles is on an even smaller scale since it is concerned with the most basic units of matter; this branch of physics is also known as high-energy physics because of the extremely high energies necessary to produce many types of particles in particle accelerators. On this scale, ordinary, commonsensical notions of space, time, matter, and energy are no longer valid.
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Though the characters would seem to have little in common, their work in fact relates to the same topic. Some ideas in the play recall Goethe's novella Elective Affinities: Stoppard's characters "Thomasina" and "Septimus" have parallels in Goethe's "Ottilie" and "Eduard", and the historical section of Stoppard's play is set in 1809, the year of Goethe's novella. Among other parallels, the older work takes the theory of affinity between chemical elements as a metaphor for ineluctable, inevitable "human chemistry" in the same way as Stoppard makes use of the force of determinism acting on his characters. A feature of both works is the preoccupation with remodelling country house landscapes; Goethe's young character "Ottilie" (the counterpart to Thomasina) dies as an indirect result of this.
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Carolinium and berzelium were the proposed names for new chemical elements that Charles Baskerville believed he had isolated from the already known element thorium. During his time at the University of North Carolina, Baskerville experimented with thorium and published his results in 1901. He reported having separated thorium into three fractions with slightly different chemical properties: the known thorium and two new elements, carolinium (symbol Cn) and berzelium (symbol Bz). The names derived from two sources: # the first element was named for the State in which the university was located at which the experiments were done, North Carolina, and # the other element was named after Jöns Jakob Berzelius, a renowned Swedish chemist and discoverer of silicon, selenium, cerium and thorium.
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A voltaic pile on display in the Tempio Voltiano (the Volta Temple) near Volta's home in Como, Italy A reproduction of the first Voltaic Pile The voltaic pile was the first electrical battery that could continuously provide an electric current to a circuit. It was invented by Italian physicist Alessandro Volta, who published his experiments in 1799. The voltaic pile then enabled a rapid series of other discoveries including the electrical decomposition (electrolysis) of water into oxygen and hydrogen by William Nicholson and Anthony Carlisle (1800) and the discovery or isolation of the chemical elements sodium (1807), potassium (1807), calcium (1808), boron (1808), barium (1808), strontium (1808), and magnesium (1808) by Humphry Davy. The entire 19th-century electrical industry was powered by batteries related to Volta's (e.g.
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These similarities led to chlorine, bromine, and iodine together being classified as one of the original triads of Johann Wolfgang Döbereiner, whose work foreshadowed the periodic law for chemical elements. It is intermediate in atomic radius between chlorine and iodine, and this leads to many of its atomic properties being similarly intermediate in value between chlorine and iodine, such as first ionisation energy, electron affinity, enthalpy of dissociation of the X2 molecule (X = Cl, Br, I), ionic radius, and X–X bond length. The volatility of bromine accentuates its very penetrating, choking, and unpleasant odour.Greenwood and Earnshaw, p. 793–4 All four stable halogens experience intermolecular van der Waals forces of attraction, and their strength increases together with number of electrons among all homonuclear diatomic halogen molecules.
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In 1888 Ivan Osipovich Yarkovsky suggested that some sort of aether is absorbed within Earth and transformed into new chemical elements, forcing the celestial bodies to expand. This was connected with his mechanical explanation of gravitation. Also the theses of Ott Christoph Hilgenberg (1933, 1974) and Nikola Tesla (1935) were based on absorption and transformation of aether-energy into normal matter. Samuel Warren Carey After initially supporting continental drift, the late Australian geologist S. Warren Carey advocated expansion from the 1950s (before the development of plate tectonics provided the generally accepted explanation of the movement of continents) to his death, demonstrating that subduction and other events could not balance the sea-floor spreading at oceanic ridges, and piling yet unresolved paradoxes that continue to plague plate tectonics.
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Significant isotopic anomalies were in turn measured by improvements in secondary ion mass spectrometry within the structural chemical elements of these grains.Ernst Zinner (1996) Stardust in the laboratory, Science 271:5245, 41-42 Improved SIMS experiments showed that the silicon isotopes within each SiC grain did not have solar isotopic ratios but rather those expected in certain red-giant stars. The finding of stardust is therefore dated 1987. To measure the isotopic abundance ratios of the structural elements (e.g. silicon in an SiC grain) in microscopic stardust grains had required two difficult technological and scientific steps: 1) locating micron-sized stardust grains within the meteorite's overwhelming mass; 2) development of SIMS technology to a sufficiently high level to measure isotopic abundance ratios within micron-sized grains.
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Central to Armstrong's philosophy is the idea of states of affairs ("facts" in Russell's terminology): in Sketch for a Systematic Metaphysics, Armstrong claims that states of affairs are "the fundamental structures in reality". A state of affairs roughly put is an instantiation of a particular and a universal: a state of affairs might be that a particular atom exists, instantiating a universal (say, that it is of a particular element, if chemical elements are ultimately accepted as part of Armstrong's universals). The particulars in Armstrong's ontology must have at least one universal—just as he rejects uninstantiated universals, he also rejects "unpropertied particulars". Armstrong argues that states of affairs are distinct things in ontology because they are more than the sum of their parts.
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The alkaline earth metals are six chemical elements in group 2 of the periodic table. They are beryllium (Be), magnesium (Mg), calcium (Ca), strontium (Sr), barium (Ba), and radium (Ra).. The elements have very similar properties: they are all shiny, silvery-white, somewhat reactive metals at standard temperature and pressure. Structurally, they (together with helium) have in common an outer s-orbital which is full; that is, this orbital contains its full complement of two electrons, which the alkaline earth metals readily lose to form cations with charge +2, and an oxidation state of +2. All the discovered alkaline earth metals occur in nature, although radium occurs only through the decay chain of uranium and thorium and not as a primordial element.
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Experimenting with the energy of beta particles in 1912, Moseley showed that high potentials were attainable from a radioactive source of radium, thereby inventing the first atomic battery, though he was unable to produce the 1MeV necessary to stop the particles. In 1913, Moseley observed and measured the X-ray spectra of various chemical elements (mostly metals) that were found by the method of diffraction through crystals. This was a pioneering use of the method of X-ray spectroscopy in physics, using Bragg's diffraction law to determine the X-ray wavelengths. Moseley discovered a systematic mathematical relationship between the wavelengths of the X-rays produced and the atomic numbers of the metals that were used as the targets in X-ray tubes.
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In chemistry, a space-filling model, also known as a calotte model, is a type of three-dimensional (3D) molecular model where the atoms are represented by spheres whose radii are proportional to the radii of the atoms and whose center-to-center distances are proportional to the distances between the atomic nuclei, all in the same scale. Atoms of different chemical elements are usually represented by spheres of different colors. Space-filling calotte models are also referred to as CPK models after the chemists Robert Corey, Linus Pauling, and Walter Koltun, who over a span of time developed the modeling concept into a useful form. They are distinguished from other 3D representations, such as the ball-and-stick and skeletal models, by the use of the "full size" space-filling spheres for the atoms.
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5, 190 (2010)R.A. Zubarev, Role of stable isotopes in life – Testing isotopic resonance hypothesis, Genomics Proteomics Bioinformatics 9, 15 (2011) postulates that certain isotopic compositions of chemical elements affect kinetics of chemical reactions involving molecules built of these elements. The isotopic compositions for which this effect is predicted are called resonance isotopic compositions. Fundamentally, the IsoRes hypothesis relies on a postulate that less complex systems exhibit faster kinetics than equivalent but more complex systems. Furthermore, system’s complexity is affected by its symmetry (more symmetric systems are simpler), and symmetry (in general meaning) of reactants may be affected by their isotopic composition. The term “resonance” relates to the use of this term in nuclear physics, where peaks in the dependence of a reaction cross section upon energy are called “resonances”.
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Sir Humphry Davy was "the most important man of science in Britain who can be described as a Romantic." His new take on what he called "chemical philosophy" was an example of Romantic principles in use that influenced the field of chemistry; he stressed a discovery of "the primitive, simple and limited in number causes of the phenomena and changes observed" in the physical world and the chemical elements already known, those having been discovered by Antoine-Laurent Lavoisier, an Enlightenment philosophe. True to Romantic anti-reductionism, Davy claimed that it was not the individual components, but "the powers associated with them, which gave character to substances"; in other words, not what the elements were individually, but how they combined to create chemical reactions and therefore complete the science of chemistry.
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Gamow would not live to see his colleague's opening of this innovative new science museum, in late August 1969. In his 1961 book The Atom and its Nucleus, Gamow proposed representing the periodic system of the chemical elements as a continuous tape, with the elements in order of atomic number wound round in a three- dimensional helix whose diameter increased stepwise (corresponding to the longer rows of the conventional periodic table). Gamow continued his teaching at the University of Colorado Boulder and focused increasingly on writing textbooks and books on science for the general public. After several months of ill health, surgeries on his circulatory system, diabetes and liver problems, Gamow was dying from liver failure, which he had called the "weak link" that could not withstand the other stresses.
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Brown was born at Haddington, East Lothian, the fourth son of Samuel Brown, the founder of itinerating libraries, and grandson of John Brown, author of the Self-Interpreting Bible. In 1832, he entered the university of Edinburgh, where, after studying in Berlin and St. Petersburg, he graduated as MD in 1839. About 1840, he was engaged in experiments by which he sought to prove that carbon in certain states of combination is susceptible of conversion into silicon, and his failure to establish this proposition had much to do with his want of success as a candidate for the chair of chemistry at Edinburgh in 1843. He held the doctrine that the chemical elements are compounds of equal and similar atoms, and might therefore possibly be all derived from one generic atom.
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This is a list of the 118 chemical elements which have been identified as of 2020. A chemical element, often simply called an element, is a species of atoms which all have the same number of protons in their atomic nuclei (i.e., the same atomic number, or Z). A popular visualization of all 118 elements is the periodic table of the elements, a convenient tabular arrangement of the elements by their chemical properties that uses abbreviated chemical symbols in place of full element names, but the simpler list format presented here may also be useful. Like the periodic table, the list below organizes the elements by the number of protons in their atoms; it can also be organized by other properties, such as atomic weight, density, and electronegativity.
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Chemist Stephen Berry explained Kenyon and Steinman's theory as "describing the following causal chain: the properties of the chemical elements dictate the types of monomers that can be formed in prebiotic syntheses, which then dictate the properties of the occurring polymers, which finally dictate the properties of the first eobionts and all succeeding cells.""Biochemical Predestination" as Heuristic Principle for Understanding the Origin of Life" by Stephen Berry, J. Chem. Educ., 1997, 74 (8), p. 950 Link Kenyon's work was about virus production."Prof Flips Theory Coin About Virus Production," Winnipeg Free Press, Wednesday, March 22, 1972. p. 43 During the 1969–1970 academic year he was "on a fellowship at the Graduate Theological Union in Berkeley, where he reviewed the contemporary literature on the relationship of science and religion.
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This is analogous to the Lyman-alpha line transition for hydrogen, and has the same frequency factor. Because the 2p electron is not screened by any other electrons in the atom from the nucleus, the nuclear charge is diminished only by the single remaining 1s electron, causing the system to be effectively a hydrogenic atom, but with a diminished nuclear charge Z − 1. Its frequency is thus the Lyman- alpha hydrogen frequency, increased by a factor of (Z − 1)2. This formula of f = c/λ = (Lyman-alpha frequency)⋅(Z − 1)2 is historically known as Moseley's law (having added a factor c to convert wavelength to frequency), and can be used to predict wavelengths of the Kα (K-alpha) X-ray spectral emission lines of chemical elements from aluminum to gold.
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Thomson published his proposed model in the March 1904 edition of the Philosophical Magazine, the leading British science journal of the day. In Thomson's view: > ... the atoms of the elements consist of a number of negatively electrified > corpuscles enclosed in a sphere of uniform positive electrification, ... With this model, Thomson abandoned his 1890 "nebular atom" hypothesis based on the vortex atomic theory in which atoms were composed of immaterial vortices and suggested that there were similarities between the arrangement of vortices and periodic regularity found among the chemical elements. Being an astute and practical scientist, Thomson based his atomic model on known experimental evidence of the day. His proposal of a positive volume charge reflects the nature of his scientific approach to discovery which was to propose ideas to guide future experiments.
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John Wallis of Kent, introduced the symbol for infinity, and the standard notation for powers of numbers in 1656. Thomas Bayes was an important statistician from Tunbridge Wells; his theorem (of probability theory) is used for spam filters and Google's search. Sir David N. Payne at the University of Southampton's Optoelectronics Research Centre invented the erbium-doped fibre amplifier, a type of optical amplifier, in the mid-1980s, which became essential for the internet. Henry Moseley at Oxford in 1913 discovered his Moseley's law of X-ray spectra of chemical elements that enabled him to be the first to assign the correct atomic number to elements in periodic table; he did not receive any Nobel Prize as it is not awarded posthumously, and he was killed in 1915 at Gallipoli with the Royal Engineers.
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Nuclear fission differs importantly from other types of nuclear reactions, in that it can be amplified and sometimes controlled via a nuclear chain reaction (one type of general chain reaction). In such a reaction, free neutrons released by each fission event can trigger yet more events, which in turn release more neutrons and cause more fission. The chemical element isotopes that can sustain a fission chain reaction are called nuclear fuels, and are said to be fissile. The most common nuclear fuels are 235U (the isotope of uranium with mass number 235 and of use in nuclear reactors) and 239Pu (the isotope of plutonium with mass number 239). These fuels break apart into a bimodal range of chemical elements with atomic masses centering near 95 and 135 u (fission products).
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As the white dwarf consists of degenerate matter, the accreted hydrogen does not inflate, but its temperature increases. Runaway fusion occurs when the temperature of this atmospheric layer reaches ~20 million K, initiating nuclear burning, via the CNO cycle. Hydrogen fusion may occur in a stable manner on the surface of the white dwarf for a narrow range of accretion rates, giving rise to a super soft X-ray source, but for most binary system parameters, the hydrogen burning is unstable thermally and rapidly converts a large amount of the hydrogen into other, heavier chemical elements in a runaway reaction, liberating an enormous amount of energy. This blows the remaining gases away from the surface of the white dwarf surface and produces an extremely bright outburst of light.
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A synthetic element is one of 24 chemical elements that do not occur naturally on Earth: they have been created by human manipulation of fundamental particles in a nuclear reactor, a particle accelerator, or the explosion of an atomic bomb; thus, they are called "synthetic", "artificial", or "man-made". The synthetic elements are those with atomic numbers 95–118, as shown in purple on the accompanying periodic table: these 24 elements were first created between 1944 and 2010. The mechanism for the creation of a synthetic element is to force additional protons onto the nucleus of an element with an atomic number lower than 95. All synthetic elements are unstable, but they decay at a widely varying rate: their half-lives range from 15.6 million years to a few hundred microseconds.
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Theodore W. Richards, a member of the International Atomic Weights Commission, was awarded the 1914 Nobel Prize in Chemistry for his work on atomic weight determination Since its establishment, many notable chemists have been members of the Commission. Notably, eight Nobel laureates have served in the Commission: Henri Moissan (1903-1907), Wilhelm Ostwald (1906-1916), Francis William Aston, Frederick Soddy, Theodore William Richards, Niels Bohr, Otto Hahn and Marie Curie. Richards was awarded the 1914 Nobel Prize in Chemistry "in recognition of his accurate determinations of the atomic weight of a large number of chemical elements" while he was a member of the Commission. Likewise, Francis Aston was a member of the Commission when he was awarded the 1922 Nobel Prize in Chemistry for his work on isotope measurements.
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Chapter XII. Anaxagoras wrote: Concerning cosmology, Anaxagoras, like some Greek philosophers already before him, believed the cosmos was revolving, and had formed into its visible order as a result of such revolving causing a separating and mixing of different types of chemical elements. Nous, in his system, originally caused this revolving motion to start, but it does not necessarily continue to play a role once the mechanical motion has started. His description was in other words (shockingly for the time) corporeal or mechanical, with the moon made of earth, the sun and stars made of red hot metal (beliefs Socrates was later accused of holding during his trial) and nous itself being a physical fine type of matter which also gathered and concentrated with the development of the cosmos.
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One can also say that for a given substance at constant pressure, absolute zero is the point of lowest enthalpy (a measure of work potential that takes internal energy, pressure, and volume into consideration).Nearly half of the 92 naturally occurring chemical elements that can freeze under a vacuum also have a closest-packed crystal lattice. This set includes beryllium, osmium, neon, and iridium (but excludes helium), and therefore have zero latent heat of phase transitions to contribute to internal energy (symbol: U). In the calculation of enthalpy (formula: H = U + pV), internal energy may exclude different sources of thermal energy (particularly ZPE) depending on the nature of the analysis. Accordingly, all T = 0 closest-packed matter under a perfect vacuum has either minimal or zero enthalpy, depending on the nature of the analysis.
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Many types of object emit copious quantities of UV radiation, though: the hottest and most massive stars in the universe can have surface temperatures high enough that the vast majority of their light is emitted in the UV. Active Galactic Nuclei, accretion disks, and supernovae all emit UV radiation strongly, and many chemical elements have strong absorption lines in the UV, so that UV absorption by the interstellar medium provides a powerful tool for studying its composition. UV astronomy was impossible before the Space Age, and some of the first space telescopes were UV telescopes designed to observe this previously inaccessible region of the electromagnetic spectrum. One particular success was the second Orbiting Astronomical Observatory, which had a number of 20 cm UV telescopes on board. It was launched in 1968, and took the first UV observations of 1200 objects, mostly stars.
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A rare-earth element (REE) or rare-earth metal (REM), as defined by the International Union of Pure and Applied Chemistry, is one of a set of seventeen chemical elements in the periodic table, specifically the fifteen lanthanides, as well as scandium and yttrium. Scandium and yttrium are considered rare-earth elements because they tend to occur in the same ore deposits as the lanthanides and exhibit similar chemical properties, but have different electronic and magnetic properties. Rarely, a broader definition that includes actinides may be used, since the actinides share some mineralogical, chemical, and physical (especially electron shell configuration) characteristics. The 17 rare-earth elements are cerium (Ce), dysprosium (Dy), erbium (Er), europium (Eu), gadolinium (Gd), holmium (Ho), lanthanum (La), lutetium (Lu), neodymium (Nd), praseodymium (Pr), promethium (Pm), samarium (Sm), scandium (Sc), terbium (Tb), thulium (Tm), ytterbium (Yb), and yttrium (Y).
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Some mineral species can have variable proportions of two or more chemical elements that occupy equivalent positions in the mineral's structure; for example, the formula of mackinawite is given as , meaning , where x is a variable number between 0 and 9. Sometimes a mineral with variable composition is split into separate species, more or less arbitrarily, forming a mineral group; that is the case of the silicates , the olivine group. Besides the essential chemical composition and crystal structure, the description of a mineral species usually includes its common physical properties such as habit, hardness, lustre, diaphaneity, colour, streak, tenacity, cleavage, fracture, parting, specific gravity, magnetism, fluorescence, radioactivity, as well as its taste or smell and its reaction to acid. Minerals are classified by key chemical constituents; the two dominant systems are the Dana classification and the Strunz classification.
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In fields as varied as mathematics, physics, astronomy, medicine, pharmacy, biology, and philosophy Latin still provides internationally accepted names of concepts, forces, objects, and organisms in the natural world. The most prominent retention of Latin occurs in the classification of living organisms and the binomial nomenclature devised by Carl Linnaeus, although the rules of nomenclature used today allow the construction of names which may deviate considerably from historical norms. Another continuation is the use of Latin names for the constellations and celestial objects (used in the Bayer designations of stars), as well as planets and satellites, whose surface features have been given Latin selenographic toponyms since the 17th century. Symbols for many of those chemical elements of the periodic table known in ancient times reflect and echo their Latin names, like Au for (gold) and Fe for (iron).
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Standard form of the periodic table of chemical elements. The colors represent different categories of elements A chemical element is a pure substance which is composed of a single type of atom, characterized by its particular number of protons in the nuclei of its atoms, known as the atomic number and represented by the symbol Z. The mass number is the sum of the number of protons and neutrons in a nucleus. Although all the nuclei of all atoms belonging to one element will have the same atomic number, they may not necessarily have the same mass number; atoms of an element which have different mass numbers are known as isotopes. For example, all atoms with 6 protons in their nuclei are atoms of the chemical element carbon, but atoms of carbon may have mass numbers of 12 or 13.
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Front cover of the Green Book Quantities, Units and Symbols in Physical Chemistry, also known as the Green Book, is a compilation of terms and symbols widely used in the field of physical chemistry. It also includes a table of physical constants, tables listing the properties of elementary particles, chemical elements, and nuclides, and information about conversion factors that are commonly used in physical chemistry. The Green Book is published by the International Union of Pure and Applied Chemistry (IUPAC) and is based on published, citeable sources. Information in the Green Book is synthesized from recommendations made by IUPAC, the International Union of Pure and Applied Physics (IUPAP) and the International Organization for Standardization (ISO), including recommendations listed in the IUPAP Red Book Symbols, Units, Nomenclature and Fundamental Constants in Physics and in the ISO 31 standards.
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He began his studies with Manuel Salvador Carmona at the Real Academia de Bellas Artes de San Fernando and won a prize for engraving in 1784. On numerous occasions, he collaborated on projects to illustrate the scientific publications of the Imprenta Real (Royal Printing Office), such as Elements of Theoretical and Experimental Physics, by the French physicist Joseph-Aignan Sigaud de Lafond (1787), The Ten Books of Architecture, by Vitruvius, translated by (1787), Physical-chemical Elements of General Water Analysis by Torbern Bergman (1794),Bergman, Elementos físico- químicos de la (sic) análisis general de las aguas, Google books. and New Inquiries About Kneecap Fractures and the Diseases that are Related to it, by the Catalonian physician Leonardo Galli (1795).Leonardo Galli, Nuevas indagaciones acerca de las fracturas de la rótula y de las enfermedades que con ella tienen relación, Google books.
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As beryllium-8 is unbound by only 92 keV, it is theorized that very small changes in nuclear potential and the fine tuning of certain constants (such as α, the fine structure constant), could sufficiently increase the binding energy of 8Be to prevent its alpha decay, thus making it stable. This has led to investigations of hypothetical scenarios in which 8Be is stable and speculation about other universes with different fundamental constants. These studies suggest that the disappearance of the bottleneck created by 8Be would result in a very different reaction mechanism in Big Bang nucleosynthesis and the triple-alpha process, as well as alter the abundances of heavier chemical elements. As Big Bang nucleosynthesis only occurred within a short period having the necessary conditions, it is thought that there would be no significant difference in carbon production even if 8Be were stable.
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According to scientists, more than 20% of the carbon in the universe may be associated with PAHs, possible starting materials for the formation of life. PAHs seem to have been formed shortly after the Big Bang, are widespread throughout the universe, and are associated with new stars and exoplanets. On August 11, 2014, astronomers released studies, using the Atacama Large Millimeter/Submillimeter Array (ALMA) for the first time, that detailed the distribution of HCN, HNC, H2CO, and dust inside the comae of comets C/2012 F6 (Lemmon) and C/2012 S1 (ISON). For the study of the recourses of chemical elements and molecules in the universe is developed the mathematical model of the molecules composition distribution in the interstellar environment on thermodynamic potentials by professor M.Yu. Dolomatov using methods of the probability theory, the mathematical and physical statistics and the equilibrium thermodynamics.
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In November 2014, Ahmed Salim announced a partnership between UNESCO and 1001 Inventions to support the United Nations proclaimed International Year of Light 2015 as founding partners and the launch of a global campaign to celebrate the work of 11th century scientist Ibn Al-Haytham in optics. UNESCO Director General Irina Bokova formalised the partnership during the high-profile opening ceremony of the International Year of Light at the UNESCO headquarters in Paris on 19 January 2015 during which Ahmed Salim addressed the audience. The global campaign engaged more than 25 million people in 2015 In October 2018, Ahmed Salim announced a new partnership between UNESCO and 1001 Inventions to support the United Nations proclaimed International Year of the Periodic Table and Chemical Elements 2019. The official opening was held at the UNESCO headquarters in Paris on 29 January 2019.
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The probability of such events increases with the neutron flux, and nuclear explosions are the most powerful man-made neutron sources, providing densities of the order 1023 neutrons/cm2 within a microsecond, or about 1029 neutrons/(cm2·s). In comparison, the flux of the HFIR reactor is 5 neutrons/(cm2·s). A dedicated laboratory was set up right at Enewetak Atoll for preliminary analysis of debris, as some isotopes could have decayed by the time the debris samples reached the mainland U.S. The laboratory was receiving samples for analysis as soon as possible, from airplanes equipped with paper filters which flew over the atoll after the tests. Whereas it was hoped to discover new chemical elements heavier than fermium, none of these were found even after a series of megaton explosions conducted between 1954 and 1956 at the atoll.
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The first edition reprinting articles from The Theosophist was published in 1908, followed by a second edition edited by Alfred Percy Sinnett in 1919, and a third edition edited by Curuppumullage Jinarajadasa in 1951.List of Sources - Occult Chemistry for Postgraduate Students of Physics, Philosophy & Psychology Since the first edition was published in 1908, the book is in the public domain, and available in whole or in excerpts, on many sites on the internet.Occult Chemistry by Annie Wood Besant and C. W. Leadbeater at Project Gutenberg Occult Chemistry states that the structure of chemical elements can be assessed through clairvoyant observation with the microscopic vision of the third eye.It was claimed by C.W. Leadbeater that, by extending an "etheric tube" from the third eye, it is possible for one to develop microscopic vision and telescopic vision.
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Bak received his bachelor's degree at the University of Copenhagen in mathematics, physics, chemistry and astronomy, specializing in organic chemistry. Immediately following his graduation, Bak served as a research assistant in the University's Department of Chemistry where he worked closely with the renowned organic chemist Einar Biilmann and spectroscopist Alex Langseth; and just the union of spectroscopy and synthetic organic chemistry formed the basis for Bak's later scientific work. Bak's contribution to the field began early with his prize winning submission to the University of Copenhagen's call for papers on the subject of organic chemical elements that won him the Gold Medal.Børge, Bak, Der ønskes en Oversigt over de kendte Metoder til Fremstilling af Tartronsyre og en eksperimentel Gennemprøvning af et Udvalg af disse, samt, om muligt, Angivelse af en forbedret eller ny og fordelagtigere Fremgangsmaade.
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Intelligent design proponents have also occasionally appealed to broader teleological arguments outside of biology, most notably an argument based on the fine-tuning of universal constants that make matter and life possible and which are argued not to be solely attributable to chance. These include the values of fundamental physical constants, the relative strength of nuclear forces, electromagnetism, and gravity between fundamental particles, as well as the ratios of masses of such particles. Intelligent design proponent and Center for Science and Culture fellow Guillermo Gonzalez argues that if any of these values were even slightly different, the universe would be dramatically different, making it impossible for many chemical elements and features of the Universe, such as galaxies, to form.Gonzalez 2004 Thus, proponents argue, an intelligent designer of life was needed to ensure that the requisite features were present to achieve that particular outcome.
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The first ideas on nucleosynthesis were simply that the chemical elements were created at the beginning of the universe, but no rational physical scenario for this could be identified. Gradually it became clear that hydrogen and helium are much more abundant than any of the other elements. All the rest constitute less than 2% of the mass of the Solar System, and of other star systems as well. At the same time it was clear that oxygen and carbon were the next two most common elements, and also that there was a general trend toward high abundance of the light elements, especially those with isotopes composed of whole numbers of helium-4 nuclei (alpha nuclides). Arthur Stanley Eddington first suggested in 1920, that stars obtain their energy by fusing hydrogen into helium and raised the possibility that the heavier elements may also form in stars.
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This rule is derived from the fact that, perhaps coincidentally, for the most common chemical elements in neutral organic compounds (hydrogen, carbon, nitrogen, oxygen, silicon, phosphorus, sulfur, and the halogens), elements with even numbered nominal masses form even numbers of covalent bonds, while elements with odd numbered nominal masses form odd numbers of covalent bonds, with the exception of nitrogen, which has a nominal (or integer) mass of 14, but has a valency of 3. The nitrogen rule is only true for neutral structures in which all of the atoms in the molecule have a number of covalent bonds equal to their standard valency (counting each sigma bond and pi bond as a separate covalent bond for the purposes of the calculation). Therefore, the rule is typically only applied to the molecular ion signal in the mass spectrum. Mass spectrometry generally operates by measuring the mass of ions.
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Surveyor 6 was the sixth lunar lander of the American uncrewed Surveyor program that reached the surface of the Moon. Surveyor 6 landed on the Sinus Medii. A total of 30,027 images were transmitted to Earth. This spacecraft was the fourth of the Surveyor series to successfully achieve a soft landing on the Moon, obtain post landing television pictures, determine the abundance of the chemical elements in the lunar soil, obtain touchdown dynamics data, obtain thermal and radar reflectivity data, and conduct a Vernier engine erosion experiment. Virtually identical to Surveyor 5, this spacecraft carried a television camera, a small bar magnet attached to one footpad, and an alpha- scattering instrument as well as the necessary engineering equipment. It landed on November 10, 1967, in Sinus Medii, 0.49 deg in latitude and 1.40 deg w longitude (selenographic coordinates)–the center of the Moon's visible hemisphere.
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Clark was born in Fairbanks, Alaska."John D. Clark, 80, Rocket Fuel Developer" (obituary) in the New York Times, July 9, 1988, page 33. He attended the University of Alaska, and then the California Institute of Technology at Pasadena, California from 1927-1930, graduating with a B.S. in Physical Chemistry. During his last two years at Caltech his college roommate was future science fiction author L. Sprague de Camp. He received an M.S. from the University of Wisconsin–Madison, and, in 1934, a PhD from Stanford University. In 1933 Clark published a novel spiral chart of the periodic system of the chemical elements. This design was used by Life Magazine for a striking and influential illustration as part of a special number on the elements, 16 May 1949. It inspired the artist Edgar Longman, whose mural was a prominent exhibit in the Festival of Britain science exhibition, London, 1951.
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Unlike most planets containing an atmosphere where the atmosphere is visibly more dense closest to the surface, planetary atmospheres in No Man's Sky are reversed as to provide a more dramatic transition when a player is taking off or landing on a planet. Other elements of their procedural generation system were made to break the realism that was previously built into the engine as to have more alien- looking planets and features be potential outcomes of the system, such as by introducing chemical elements that would enable green-tinted atmospheres and allowing moons to orbit much closer than the laws of gravity would allow to create impressive backdrops on planets. To assure that the procedural generation worked well, the development team created the in-game equivalent of automated probes to visit the various planets and take images to review; this allowed for some tweaks to be made by human developers.
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An extended periodic table theorises about chemical elements beyond those currently known in the periodic table and proven up through oganesson, which completes the seventh period (row) in the periodic table at atomic number (Z) 118. , no element with a higher atomic number than oganesson has been successfully synthesized; all elements in the eighth period and beyond thus remain purely hypothetical. If further elements with higher atomic numbers than this are discovered, they will be placed in additional periods, laid out (as with the existing periods) to illustrate periodically recurring trends in the properties of the elements concerned. Any additional periods are expected to contain a larger number of elements than the seventh period, as they are calculated to have an additional so-called g-block, containing at least 18 elements with partially filled g-orbitals in each period. An eight-period table containing this block was suggested by Glenn T. Seaborg in 1969.
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With his focus on radioactive supernova gas Clayton discovered a new chemical pathway causing carbon dust to condense there by a process that is activated by the radioactivity.“A New Astronomy with Radioactivity: Radiogenic Carbon Chemistry”, New Astronomy Reviews, 55, 155–65 (2011)] Clayton's foundational ideas for five original subfields of astrophysics are detailed in Section 5 below. They are: (1) nucleosynthesis, the assembly within stars of the atomic nuclei of the common chemical elements by nuclear reactions occurring therein; (2) astronomical detection of gamma-ray lines emitted by radioactive atoms created and ejected by supernovae; (3) mathematical models of the growth over time of the interstellar abundances of radioactive atoms; (4) predictions of the existence of interstellar cosmic dust grains from individual stars—individual chunks of long-dead stars. He named those stardust, each containing isotopically identifiable radioactive atoms of the host stars; (5) predictions of the condensation of solid grains of pure carbon within hot, oxygen-dominated radioactive supernova gases.
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In an attempt at a chemical conception of the aether, he put forward a hypothesis that there existed two inert chemical elements of lesser atomic weight than hydrogen. Of these two proposed elements, he thought the lighter to be an all-penetrating, all-pervasive gas, and the slightly heavier one to be a proposed element, coronium. Mendeleev devoted much study and made important contributions to the determination of the nature of such indefinite compounds as solutions. Mendeleev Medal In another department of physical chemistry, he investigated the expansion of liquids with heat, and devised a formula similar to Gay-Lussac's law of the uniformity of the expansion of gases, while in 1861 he anticipated Thomas Andrews' conception of the critical temperature of gases by defining the absolute boiling-point of a substance as the temperature at which cohesion and heat of vaporization become equal to zero and the liquid changes to vapor, irrespective of the pressure and volume.
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As viewed by Chandrayaan-1's NASA Moon Mineralogy Mapper equipment, on the right, the first time discovered water-rich minerals (light blue), shown around a small crater from which it was ejected. The European spacecraft SMART-1, the second ion-propelled spacecraft, was in lunar orbit from 15 November 2004 until its lunar impact on 3 September 2006, and made the first detailed survey of chemical elements on the lunar surface. The ambitious Chinese Lunar Exploration Program began with Chang'e 1, which successfully orbited the Moon from 5 November 2007 until its controlled lunar impact on 1 March 2009. It obtained a full image map of the Moon. Chang'e 2, beginning in October 2010, reached the Moon more quickly, mapped the Moon at a higher resolution over an eight-month period, then left lunar orbit for an extended stay at the Earth–Sun L2 Lagrangian point, before finally performing a flyby of asteroid 4179 Toutatis on 13 December 2012, and then heading off into deep space.
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Schlesinger has a long research career studying the circulation of the chemical elements in natural ecosystems—now widely known as biogeochemistry. Most of his work has focused on soils, especially on the carbon stored in soils, which contain a major pool in the global carbon cycle. His early work provided estimates of the storage of organic carbon (humus) and inorganic carbon (largely calcium carbonate) in soils, losses of soil carbon to runoff, changes in soil carbon with conversion of land to agriculture, and accumulations of carbon during soil development. More recently, he has examined changes in soil processes and soil carbon storage that accompany plant growth at elevated levels of atmospheric carbon dioxide, as simulated in the Duke Forest Free-Air CO2 Enrichment (FACE) experiment. His work also evaluates recommendations for carbon sequestration as a means to control the accumulation of CO2 in Earth’s atmosphere and to mitigate the potential for global warming.
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Since moving to Trondheim in 1977, Naqvi has worked on a wide range of problems within physics, chemistry and biology, dividing his time equally between theory and experiment and between the pure and the applied. These topics include: (1) calculation of Franck–Condon factors, (2) applications of linear transport theory to chemical kinetics, diffuse reflection spectroscopy, and phonon transport in semiconductors, (3) spectroscopy of absorbing and scattering specimens, (4) primary photophysical processes in carotenoids, vitamin E and related molecules, (5) revival of quantum wave packets, (6) photoprotection in artificial and natural photosynthesis, (7) use of diffusive gradient in thin films (DGTF) for the in situ measurement of the labile forms of chemical elements in aqueous environments, sediments and soils, and (8) non-invasive measurement of blood pressure. Naqvi’s many coauthors include a very large number of scientists from all over the world. Within NTNU, his collaborators include, apart from many physicists, several chemists (analytical, organic, physical) and two mathematicians.
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The Disappearing Spoon: And Other True Tales of Madness, Love, and the History of the World from the Periodic Table of the Elements, is a 2010 book by science reporter Sam Kean. The book was first published in hardback on July 12, 2010 through Little, Brown and Company and was released in paperback on June 6, 2011 through Little, Brown and Company's imprint Back Bay Books. The book focuses on the history of the periodic table by way of short stories showing how a number of chemical elements affected their discoverers, for either good or bad. People discussed in the book include the physicist and chemist Marie Curie, whose discovery of radium almost ruined her career; the writer Mark Twain, whose short story "Sold to Satan" featured a devil who was made of radium and wore a suit made of polonium; and the theoretical physicist Maria Goeppert-Mayer, who earned a Nobel Prize in Physics for her groundbreaking work, yet continually faced opposition owing to her sex.
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Young Earth creationism is most famous for an opposition to the theory of evolution, but believers also are on record opposing many measurements, facts, and principles in the fields of physics and chemistry, dating methods including radiometric dating, geology, astronomy, cosmology, and paleontology. Young Earth creationists do not accept any explanation for natural phenomena which deviates from the veracity of a plain reading of the Bible, whether it be the origins of biological diversity, the origins of life, the geological, atmospheric, and oceanic history of Earth, the origins of the Solar System and Earth, formation of the earliest chemical elements or the origins of the universe itself. This has led some young Earth creationists to criticize other creationist proposals such as intelligent design, for not taking a strong stand on the age of the Earth, special creation, or even the identity of the designer. Young Earth creationists disagree with the methodological naturalism that is part of the scientific method.
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The Center for Advanced Study Marsilius Kolleg, situated in House Buhl, was founded in 2007 Among historical scientific achievements of Heidelberg researchers features prominently the invention of spectroscopy, and of the Bunsen burner; the discovery of chemical elements Caesium and Rubidium; the identification of the absolute point of ebullition; and the identification and isolation of nicotine as the main pharmacologically active component of tobacco. Modern scientific psychiatry; psychopharmacology; psychiatric genetics; environmental physics; and modern sociology were introduced as scientific disciplines by Heidelberg faculty. Almost 800 dwarf planets, the North America Nebula, and the return of Halley's Comet have been discovered and documented at institutes of the Heidelberg Center for Astronomy. Moreover, Heidelberg researchers invented the process of plastination to preserve body tissue, conducted the first successful transplantation of hematopoietic stem cells, and recently developed a new strategy for a vaccination against certain forms of cancer, which earned Harald zur Hausen of the university the Nobel Prize in Physiology or Medicine 2008.
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Molar heat capacity of most elements at 25 °C is in the range between 2.8 R and 3.4 R: Plot as a function of atomic number with a y range from 22.5 to 30 J/mol K. The Dulong–Petit law, a thermodynamic law proposed in 1819 by French physicists Pierre Louis Dulong and Alexis Thérèse Petit, states the classical expression for the molar specific heat capacity of certain chemical elements. Experimentally the two scientists had found that the heat capacity per weight (the mass-specific heat capacity) for a number of elements was close to a constant value, after it had been multiplied by a number representing the presumed relative atomic weight of the element. These atomic weights had shortly before been suggested by John Dalton and modified by Jacob Berzelius. In modern terms, Dulong and Petit found that the heat capacity of a mole of many solid elements is about 3R, where R is the modern constant called the universal gas constant.
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"Willo"'s supposed "heart" A study published in 2011 applied multiple lines of inquiry to the question of the object's identity, including more advanced CT scanning, histology, X-ray diffraction, X-ray photoelectron spectroscopy, and scanning electron microscopy. From these methods, the authors found the following: the object's internal structure does not include chambers but is made up of three unconnected areas of lower density material, and is not comparable to the structure of an ostrich's heart; the "walls" are composed of sedimentary minerals not known to be produced in biological systems, such as goethite, feldspar minerals, quartz, and gypsum, as well as some plant fragments; carbon, nitrogen, and phosphorus, chemical elements important to life, were lacking in their samples; and cardiac cellular structures were absent. There was one possible patch with animal cellular structures. The authors found their data supported identification as a concretion of sand from the burial environment, not the heart, with the possibility that isolated areas of tissues were preserved.
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The stone-like mineral could be broken up into smaller fragments and used as a laundry detergent. S. rosmarinus growing on small sand mounds in Qatar Some of the salt bushes produced a type of potassium alum (Arabic: shab) that was brownish in color, having a strong alkalinity and burning effect when tasted. Al-Tamimi adds that one of the chemical elements had by burning Seidlitzia's succulent green leaves is al-qalī, which, besides being a natural cleansing agent, its "plant ashes" (potash) could be converted into potassiumMany of the saltworts, such as Salsola spp., including Seidlitzia, are known to contain high amounts of potassium chloride (KCl), potassium carbonate (K2CO3) and potassium hydroxide (KOH), and which combined minerals were given the general name of alkali (qelw) among the Arabs (Zohar Amar and Yaron Serri, The Land of Israel and Syria as Described by al-Tamimi – Jerusalem Physician of the 10th Century, Ramat-Gan 2004, p.
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On Earth, phosphorus is washed into the oceans by rainwater hitting rocks on exposed land so the mechanism would not work on an ocean world. Simulations of ocean planets with 50 Earth oceans' worth of water indicate the pressure on the sea floor would be so immense that the planet's interior would not sustain plate tectonics to cause volcanism to provide the right chemical environment for terrestrial life. On the other hand, small bodies such as Europa and Enceladus are regarded as particularly habitable environments because their oceans are in direct contact with the underlying silicate core, a potential source of both heat and biologically important chemical elements. The surface geological activity of these bodies may also lead to the transport to the oceans of biologically-important building blocks implanted at the surface, such as organic molecules from comets or tholins —formed by solar ultraviolet irradiation of simple organic compounds such as methane or ethane, often in combination with nitrogen.
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However, the essential novelty of Dalton's atomic theory is that he provided a method of calculating relative atomic weights for the chemical elements, something that neither Bryan nor William Higgins did; his priority for that crucial step is uncontested. A study of Dalton's laboratory notebooks, discovered in the rooms of the Manchester Literary and Philosophical Society, concluded that so far from Dalton being led by his search for an explanation of the law of multiple proportions to the idea that chemical combination consists in the interaction of atoms of definite and characteristic weight, the idea of atoms arose in his mind as a purely physical concept, forced on him by study of the physical properties of the atmosphere and other gases. The first published indications of this idea are to be found at the end of his paper "On the Absorption of Gases by Water and other Liquids" already mentioned. There he says: He then proposes relative weights for the atoms of a few elements, without going into further detail.
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In 1995, inspired by Dyson's 1970 suggestion of seeding uninhabited deserts on Earth with self-replicating machines for industrial development, Klaus Lackner and Christopher Wendt developed a more detailed outline for such a system.Lackner, Klaus S., and Wendt, Christopher H., "Self-reproducing machine systems for global scale projects," Document LA-UR-93-2886, 4th International Conference and Exposition on Engineering, Construction and Operations in Space/Conference and Exposition/Demonstrations on Robotic for Challenging Environments, Albuquerque, New Mexico, 26 February – 3 March 1994 They proposed a colony of cooperating mobile robots 10–30 cm in size running on a grid of electrified ceramic tracks around stationary manufacturing equipment and fields of solar cells. Their proposal didn't include a complete analysis of the system's material requirements, but described a novel method for extracting the ten most common chemical elements found in raw desert topsoil (Na, Fe, Mg, Si, Ca, Ti, Al, C, O2 and H2) using a high-temperature carbothermic process. This proposal was popularized in Discover Magazine, featuring solar-powered desalination equipment used to irrigate the desert in which the system was based.
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These rare objects, known as metal-poor stars, are the most chemically primitive stars known, and are among the first generations of stars born in our galaxy, the Milky Way. They provide crucial information on the astrophysical nucleosynthesis sites of the chemical elements, and are powerful tracers of the assembly and evolution of large spiral galaxies. Beers’ discoveries include: (1) The identification of the first metal-poor stars with measured abundances of Uranium, enabling the determination of a radioactive decay age limit on the Universe, (2) a class of stars known as carbon-enhanced metal- poor (CEMP) stars, a subset of which are thought to reflect the nucleosynthesis products of the very first stars in the Universe, and (3) The first large-scale chronographic (age) maps of the halo of the Milky Way, which astronomers can compare with simulations of the formation of the galaxy. In 2017, Beers and his graduate students were part of a team that identified the characteristic signature of the astrophysical r-process in the kilonova associated with a neutron star merger.
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Computed tomography (CT) scans conducted in 2000 of the chest cavity of a specimen of the ornithopod Thescelosaurus found the apparent remnants of a complex four-chambered heart, much like those found in today's mammals and birds. The idea is controversial within the scientific community, criticised for being bad anatomical science or simply wishful thinking. A study published in 2011 applied multiple lines of inquiry to the question of the object's identity, including more advanced CT scanning, histology, X-ray diffraction, X-ray photoelectron spectroscopy, and scanning electron microscopy. From these methods, the authors found that: the object's internal structure does not include chambers but is made up of three unconnected areas of lower density material, and is not comparable to the structure of an ostrich's heart; the "walls" are composed of sedimentary minerals not known to be produced in biological systems, such as goethite, feldspar minerals, quartz, and gypsum, as well as some plant fragments; carbon, nitrogen, and phosphorus, chemical elements important to life, were lacking in their samples; and cardiac cellular structures were absent.
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For a few illustrative examples: German speakers use "Wasserstoff" (water substance) for "hydrogen", "Sauerstoff" (acid substance) for "oxygen" and "Stickstoff" (smothering substance) for "nitrogen", while English and some romance languages use "sodium" for "natrium" and "potassium" for "kalium", and the French, Italians, Greeks, Portuguese and Poles prefer "azote/azot/azoto" (from roots meaning "no life") for "nitrogen". For purposes of international communication and trade, the official names of the chemical elements both ancient and more recently recognized are decided by the International Union of Pure and Applied Chemistry (IUPAC), which has decided on a sort of international English language, drawing on traditional English names even when an element's chemical symbol is based on a Latin or other traditional word, for example adopting "gold" rather than "aurum" as the name for the 79th element (Au). IUPAC prefers the British spellings "aluminium" and "caesium" over the U.S. spellings "aluminum" and "cesium", and the U.S. "sulfur" over the British "sulphur". However, elements that are practical to sell in bulk in many countries often still have locally used national names, and countries whose national language does not use the Latin alphabet are likely to use the IUPAC element names.
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In the periodic table, because atoms of elements in a column usually have the same outer electron structure, and always have the same electron structure in the "s-block" and "p-block" elements (see block (periodic table)), all elements may share the same ground state term symbol for the column. Thus, hydrogen and the alkali metals are all 2S, the alkali earth metals are 1S0, the boron column elements are 2P, the carbon column elements are 3P0, the pnictogens are 4S, the chalcogens are 3P2, the halogens are 2P, and the inert gases are 1S0, per the rule for full shells and subshells stated above. Term symbols for the ground states of most chemical elements are given in the collapsed table below (with citations for the heaviest elements here). In the d-block and f-block, the term symbols are not always the same for elements in the same column of the periodic table, because open shells of several d or f electrons have several closely spaced terms whose energy ordering is often perturbed by addition of an extra complete shell to form the next element in the column.
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