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"rare-earth element" Definitions
  1. any of a group of closely related metallic elements, comprising the lanthanides, scandium, and yttrium, that are chemically similar by virtue of having the same number of valence electrons.
"rare-earth element" Synonyms
base metal native metal noble metal oxide precious metal rare earth rare-earth metal rare metal lanthanide lanthanate lanthanoid lanthanon

144 Sentences With "rare earth element"

How to use rare earth element in a sentence? Find typical usage patterns (collocations)/phrases/context for "rare earth element" and check conjugation/comparative form for "rare earth element". Mastering all the usages of "rare earth element" from sentence examples published by news publications.

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The redesigned motor still uses a light rare earth element, neodymium.
The rare earth element cerium, for example, is the 25th most abundant on Earth, making it about as common as copper.
Lynas said in June it was stockpiling production of rare earth element Neodymium Praseodymium (NdPr) for strategic customers amid Sino-U.
The company said in June it was stockpiling production of rare earth element Neodymium Praseodymium (NdPr) for strategic customers amid China-U.
He's found high rare earth element content in coal seams — coal deposits that can be seen inside of rocks — and coal ash.
China has invested in at least four key mining operations in Greenland, adding to its dominant position in the rare earth element market.
And not a single high-tech magnet needed for military equipment is made in the U.S. Roughly 91 percent of the rare earth element needed for night-vision googles comes from China.
But left to free market forces, it's going to be a long time before the United States is going to produce enough yttrium or any other rare earth element to meet its needs.
Since Trump took office in January, Ghani and his government have been talking up the economic promise of Afghanistan's mineral resources, especially lithium, a comparatively rare earth element that's used in cellphone and laptop batteries.
MELBOURNE (Reuters) - Australia's Lynas Corp said it was stockpiling production of a major rare earth element, with prices jumping in recent weeks as supply concerns mount amid trade tensions between China and the United States.
In April, U.S. Senators Joe Manchin, Shelley Moore Capito and Lisa Murkowski introduced the Rare Earth Element Advanced Coal Technologies Act, which would allocate $23 million a year to the Department of Energy and its National Energy Technology Laboratory (NETL) through 2027 to help develop technologies that could extract rare earth elements from coal and coal by-products in U.S. mines.
The rare-earth element concentrations are not typically affected by sea and river waters, as rare-earth elements are insoluble and thus have very low concentrations in these fluids. As a result, when a sediment is transported, rare-earth element concentrations are unaffected by the fluid and instead the rock retains the rare-earth element concentration from its source. Sea and river waters typically have low rare-earth element concentrations. However, aqueous geochemistry is still very important.
Lanthanum hydroxide is , a hydroxide of the rare-earth element lanthanum.
The rare-earth element contents are transitional between Planchon-Peteroa and Patagonia alkali basalt signatures.
When the rare earth element-enriched felsic magma cools down to become rock, intense weathering of the rock further concentrates the rare earth element deposit. Therefore, the property of magma and the weathering intensity is the key to concentrate the rare earth element deposits. In South China, 75% of these deposits were derived from granitic and volcanic rocks during the Jurassic to the early Cretaceous. Therefore, the Yanshanian Movement represents one of the vital geological events in South China.
Hence, regolith-hosted rare earth element deposits were recognised and extraction technologies have been rapidly developed since the 1980s. Currently, China dominates more than 95% of the global REE production. Regolith-hosted rare earth element deposits, which contributes 35% of China's REE production, are mainly found in South China.
The rare earth element Neodymium is extracted by di(2-ethyl-hexyl)phosphoric acid into hexane by an ion exchange mechanism.
In terms of trace element characteristics, Archean TTGs exhibit high light rare earth element (LREE) content yet low heavy rare earth element (HREE) content. However, they do not show Eu and Sr anomalies. These features indicate the presence of garnet and amphibole, but no plagioclase in the residual phase during partial melting or precipitation phase during fractional crystallization.
Synchysite-(Ce) is found in rare-earth element bearing pegmatites. It can also occur as a hydrothermal mineral in granite, alkalic syenite and carbonatite.
Regolith-hosted rare earth element deposits are found along ridges in low-lying granitic hills in South China.Yang, D.-H., Xiao, G.-M., 2011.
Superconducting layer in the 2nd generation superconducting wires can be grown by reactive co-evaporation of constituent metals, rare-earth element, barium, and copper.
The magnetic medium are typically amorphous R-Fe-Co thin film (R being a rare earth element). Magneto-optical recording is not very popular. One famous example is Minidisc developed by Sony.
Dollaseite-(Ce) forms as dark-brown subhedral crystals primarily in Swedish mines. With the ideal chemical formula, , dollaseite-(Ce) can be partially identified by its content of the rare earth element cerium.
In regolith-hosted rare earth element deposits, rare earth elements ores do not exist as free ions. Instead, they physically adhere on clay minerals as clay-REE complex or chemically bond with REE-hosting minerals.
Production of REE around the world A rare-earth element-iron-lead-zinc (REE-Fe-Pb-Zn) system was formed from extensional rifting with upwelling of mantle, and therefore magma fractionation. There were multiple rifting events resulting in the deposition of iron minerals and the occurrence rare earth element was closely related to the iron and carbonatite dykes. The REE-Fe-Pb-Zn system occurs in an alternating volcanic and sedimentary succession. Apart from REE, LREE (light rare earth elements) are also found in carbonatite dykes.
It takes its name from its two primary components: iron (from ), and the rare-earth element cerium.van Weert, Ad, Joop Bromet, Alice van Weert (1995). The Legend of the Lighter. New York: Abbeville Press, p. 45.
More importantly, it is responsible for the chemical reactions in the converter. Gadolinium compounds are the active component in various MRI contrast agents. For more applications of other rare earth elements, check "Rare-earth element#List".
S-type granites contain elevated levels of K, Rb and Pb, and are depleted in Sr. With respect to rare earth elements, S-type granites are light rare earth element depleted compared to other granite types.
The Bayan Obo iron ore deposit in Inner Mongolia contains significant amounts of bastnäsite and monazite and is, with an estimated 36 million tonnes of rare-earth element oxides, the largest known deposit. The mining operations at the Bayan Obo deposit made China the largest supplier of rare-earth elements in the 1990s. Only 0.2% of the rare-earth element content is europium. The second large source for rare-earth elements between 1965 and its closure in the late 1990s was the Mountain Pass rare earth mine in California.
Gadolinium(III) oxide (archaically gadolinia) is an inorganic compound with the formula Gd2O3. It is one of the most commonly available forms of the rare- earth element gadolinium, derivatives of which are potential contrast agents for magnetic resonance imaging.
Rapitan types are associated with the glaciogenic sequences of the Archean and Early Proterozoic. The type is distinctive as the hydrothermal-input has notably less influence on this formation's Rare Earth Element (REE) chemistry than other formations during this time period.
250x250px In understanding metamorphic rocks, Lu–Hf can still provide information of origin. In cases where zircon phase is absent or very low in abundance, such as eclogite with cumulate protolith, kyanite and orthopyroxene eclogites can be candidate for Hf analysis. Although the overall rare-earth element concentration is low is the two eclogites, Lu/Hf ratios is high, therefore enabling concentration determination of Lu and Hf. Garnets play an important role in Lu/Hf applications, as they are common metamorphic minerals while having high affinity to rare-earth element. This means garnets generally have high Lu/Hf ratios.
An important development came in 1924 with Wolfgang Pauli's discovery of the Pauli exclusion principle, which put Bohr's models on a firm theoretical footing. Bohr was then able to declare that the as-yet-undiscovered element 72 was not a rare-earth element, but an element with chemical properties similar to those of zirconium. He was immediately challenged by the French chemist Georges Urbain, who claimed to have discovered a rare-earth element 72, which he called "celtium". At the Institute in Copenhagen, Dirk Coster and George de Hevesy took up the challenge of proving Bohr right and Urbain wrong.
They were emplaced in a compressional regime in an arc tectonic setting within a crust of about 30 km thickness. The rare earth element patterns of these granites suggest that they were subduction related, supporting the obtained magmatic affinity and the tectonic setting.
Lanthanites are a group of isostructural rare earth element (REE) carbonate minerals. This group comprises the minerals lanthanite-(La),Haidinger W (1845) Zweite Klasse: Geogenide. II. Ordnung. Baryte. III. Cerebaryt. Lanthanit., in Handbuch der Bestimmenden Mineralogie, Bei Braumüller and Seidel (Wien) 499-506.
Lanthanum oxide, also known as lanthana, chemical formula La2O3, is an inorganic compound containing the rare earth element lanthanum and oxygen. It is used in some ferroelectric materials, as a component of optical materials, and is a feedstock for certain catalysts, among other uses.
Secondary process (i.e. weathering) is essential in further enrichment of HREE-/LREE- rich granitoid. It turns the granitoid to an economically-extractable orebody. Therefore, warm and humid climate, together with slightly acidic soil in subtropical zones favour the formation of regolith-hosted rare earth element deposits.
Experts from Technical University of Denmark estimate that a geared generator with permanent magnets may use 25 kg/MW of the rare-earth element Neodymium, while a gearless may use 250 kg/MW.Wittrup, Sanne. PMs cause production problems English translation Ing.dk, 1 November 2011. Accessed: 1 November 2011.
Gadolinium is a chemical element with the symbol Gd and atomic number 64. Gadolinium is a silvery-white metal when oxidation is removed. It is only slightly malleable and is a ductile rare-earth element. Gadolinium reacts with atmospheric oxygen or moisture slowly to form a black coating.
The chemical composition of upconverting nanoparticles, UCNPs, directly influences their conversion efficiency and spectral characteristics. Primarily, three compositional parameters influence the particles’ performance: the host lattice, activator ions, and sensitizer ions. The NaYF4:RE cubic unit cell. Key: Na (Teal), rare-earth element (RE, pink), and F (yellow).
Bohuslav Brauner (May 8, 1855 - February 15, 1935) was a Czech chemist from the University of Prague, who investigated the properties of the rare earth elements, especially the determination of their atomic weights. Brauner predicted the existence of the rare earth element promethium ten years before its discovery.
In 2013, a US-based Solyndra solar farm left over 5,670 metric tons of hazardous waste after it bankrupted after 4 years of operations. Manufacturing of solar panels requires rare-earth elements, producing low-level radioactive waste during the mining process (see also: Rare-earth element#Environmental considerations).
Monazite is a rare-earth-element phosphate mineral, with the chemical formula e.g. (Ce, La, Nd, Th, Y)PO4. It appears in a small amount as an accessory mineral in many igneous, metamorphic and sedimentary rocks. Monazite minerals contain significant amounts of radioactive elements Th and U, which trigger radioactive processes.
Li, Y., Burns, P. C., and Gault, R. A., 2000. A new rare-earth-element uranyl carbonate sheet in the structure of bijvoetite-(Y). The Canadian Mineralogist 38, 153-162. Bijvoetite-(Y) is an example of natural salts containing both uranium and yttrium, the other examples being kamotoite-(Y) and sejkoraite-(Y).
Both meteorites contain pyroxene and have a number of other similarities: for example their pyroxene composition, rare-earth element concentrations, and oxygen isotope ratios. However, there are also indicators against the grouping of these two meteorites: for example the texture and occurrence of cohenite in the Vermillion meteorite and the differing siderophile trace element concentrations.
A sulfite sulfate is a chemical compound that contains both sulfite and sulfate anions [SO3]2− [SO4]2−. These compounds were discovered in the 1980s as calcium and rare earth element salts. Minerals in this class were later discovered. Minerals may have sulfite as an essential component, or have it substituted for another anion as in alloriite.
Europium is exempt of this classification as it has two valence states: Eu and Eu. Yttrium is grouped as heavy rare-earth element due to chemical similarities. The 1985 International Union of Pure and Applied Chemistry "Red Book" (p. 45) recommends that lanthanoid is used rather than lanthanide. The ending "-ide" normally indicates a negative ion.
Wakefieldite ((La,Ce,Nd,Y)VO4) is an uncommon rare-earth element vanadate mineral. There are four main types of wakefieldite- wakefieldite-(La), wakefieldite-(Ce), wakefieldite-(Nd), and wakefieldite-(Y), depending upon the dominant rare-earth metal ion present. Wakefieldite has a Mohs hardness ranging from 4 to 5.The Mineral and Locality Database, Wakefieldite-(La).
Thomasclarkite-(Y) is a rare mineral which was known as UK-93 until 1997, when it was renamed in honour of Thomas H. Clark (1893–1996), McGill University professor. The mineral is one of many rare-earth element minerals from Mont Saint-Hilaire. The only reported occurrence is in an alkalic pegmatite dike in an intrusive gabbro-nepheline syenite.
313, p. 78–92. # Suarez, C.A., Macpherson, G.L., González, L.A., and Grandstaff, D.E. (2010) Heterogeneous rare earth element (REE) patterns and concentrations in a fossil bone as determined by LAM-ICP-MS analysis: implications for the use of REE in vertebrate taphonomy and fossilization history: Geochimica et Cosmochimica Acta. v. 74, p. 2970–2988. # Suarez, C.A., Suarez.
Among rare earth element products are lanthanum, cerium, praseodymium, neodymium and samarium-europium-gadolinium carbonates, oxides, metals, chloride and nitrate solutions. On 4 April 2011, the American rare earth metal producer Molycorp announced its acquisition of a 90% stake in AS Silmet. The deal was valued at $89 million at the time. The company was renamed AS Silmet- Molycorp.
In terms of tectonic settings, no obvious trend in tectonic setting that favours the formation of regolith-hosted rare earth element deposits is observed. Geologists had long believed that among different magma sources, magmas originated formed anorogenic (non-mountain building) and anhydrous settings (e.g. divergent plate boundaries), which consequently form A-type granites, are REEs-enriched.Cui, Y., 2014.
China has many different types of mineral resources and has global significant reserves of many of them. They are frequently in the global top 10 countries for mineral reserves or production. They produce more than 90% of the global rare earth element ore. Chrysotile (asbestos) is still mined and used extensively in China as a construction material.
Dysprosium is a chemical element with the symbol Dy and atomic number 66. It is a rare-earth element with a metallic silver luster. Dysprosium is never found in nature as a free element, though it is found in various minerals, such as xenotime. Naturally occurring dysprosium is composed of seven isotopes, the most abundant of which is 164Dy.
Dysprosium sample Dysprosium is a rare-earth element and has a metallic, bright silver luster. It is quite soft and can be machined without sparking if overheating is avoided. Dysprosium's physical characteristics can be greatly affected by even small amounts of impurities. Dysprosium and holmium have the highest magnetic strengths of the elements, especially at low temperatures.
Holmium is a chemical element with the symbol Ho and atomic number 67. Part of the lanthanide series, holmium is a rare-earth element. Holmium was discovered through isolation by Swedish chemist Per Theodor Cleve and independently by Jacques-Louis Soret and Marc Delafontaine who observed it spectroscopically in 1878. Its oxide was first isolated from rare-earth ores by Cleve in 1878.
The Vanadium Corporation of America was a commercial producer of vanadium, a rare-earth element and a strengthening additive for steel. The company was founded in 1906 by Joseph M. Flannery and was headquartered in Pittsburgh, Pennsylvania. The company operated several vanadium mines in multiple countries, including Peru. The raw material was converted into a ferroalloy at its plant in Bridgeville, Pennsylvania.
Neodymium is a chemical element with the symbol Nd and atomic number 60. Neodymium belongs to the lanthanide series and is a rare-earth element. It is a hard, slightly malleable silvery metal that quickly tarnishes in air and moisture. When oxidized, neodymium reacts quickly to produce pink, purple/blue and yellow compounds in the +2, +3 and +4 oxidation states.
Hence, it can be recovered as a by-product of other mining activities. Already, large quantities of thorium recovered from rare-earth element operations have been stockpiled in many countries. Thorium is fertile material, and essentially all thorium can be used in a nuclear reactor. Thorium is not fissile in itself, absorbs a neutron to transmute into uranium-233, which can fission to produce energy.
Scandiobabingtonite was first discovered in the Montecatini granite quarry near Baveno, Italy in a pegmatite cavity. Though found in pegmatites, the crystals of scandiobabingtonite are sub-millimeter sized, and are tabular shaped. Scandiobabingtonite was the sixth naturally occurring mineral discovered with the rare earth element scandium, and grows around babingtonite, with which it is isostructural, hence the namesake. It is also referred to as scandian babingtonite.
In 1945 he was a member of the Clinton Laboratories team, with Jacob Marinsky and Lawrence E. Glendenin, that isolated the previously undocumented rare- earth element 61.Reactor Chemistry -- Discovery of Promethium , ORNL Review, Vol. 36, No. 1, 2003 Marinsky and Glendenin produced this element (later named "promethium") both by extraction from fission products and by bombarding neodymium with neutrons. They isolated it using ion-exchange chromatography.
He worked as a chemist at the Clinton Laboratories (now Oak Ridge National Laboratory) during the World War II Manhattan Project, engaged in separating, identifying and characterizing the radioactive elements produced by nuclear fission. In 1945, he, together with Jacob A. Marinsky and Charles D. Coryell, isolated the previously undocumented rare-earth element 61.Reactor Chemistry – Discovery of Promethium , ORNL Review, Vol. 36, No. 1, 2003.
The most important mineral resources in the South China Block must be the rare earth element (REE). REEs have a very wide range of application. Nowadays, China accounts for more than 80% of the global REE production. A lot of weathering- related REE deposit are found in South China such as the Zudong deposit and the Guposhan deposit in Jiangxi and Guangxi province respectively.
An example of a plumbide is CeRhPb. The lead atom has a coordination number of 12 in the crystal structure of this compound. It is bound to four rhodiums, six ceriums, and two other lead atoms in the crystal structure of the chemical. Several other plumbides are the M2Pd2Pb plumbides, where M is a rare-earth element, and the intermetallic additionally contains a palladium.
There is an impending increase in the costs of many rare materials used in the manufacture of hybrid cars./ For example, the rare earth element dysprosium is required to fabricate many of the advanced electric motors and battery systems in hybrid propulsion systems. Neodymium is another rare earth metal which is a crucial ingredient in high-strength magnets that are found in permanent magnet electric motors.Choruscars.com .
Scandium-doped LCSM (LSCMS) is also being researched as a cathode material due to its high ionic conductivity. However, the rare-earth element introduces a significant materials cost and was found to cause a slight decrease in overall mixed conductivity. Nonetheless, LCSMS materials have demonstrated high efficiency at temperatures as low as 700 °C.Chen, S., Xie, K., Dong, D., Li, H., Qin, Q., Zhang, Y., & Wu, Y. (2015).
The uranium, thorium, and potassium in particular were used to map the location of KREEP (potassium, rare-earth element, and phosphorus containing material, which is thought to have developed late in the formation of the crust and upper mantle, and is therefore important to understanding lunar evolution). The GRS was also capable of detecting fast (epithermal) neutrons, which complemented the neutron spectrometer in the search for water on the Moon.
It has a variant , reversed under the influence of the initial letter 'C' of 'Ceres'. These symbols were later replaced with the generic asteroid symbol of a numbered disk, . Cerium, a rare-earth element discovered in 1803, was named after Ceres. In the same year, another element was also initially named after Ceres, but, when cerium was named, its discoverer changed the latter to palladium, after the second asteroid, 2 Pallas.
Yttrium is a chemical element with symbol Y and atomic number 39. It is a silvery-metallic transition metal chemically similar to the lanthanides and it has often been classified as a "rare earth element". Yttrium is almost always found combined with the lanthanides in rare earth minerals and is never found in nature as a free element. Its only stable isotope, 89Y, is also its only naturally occurring isotope.
The oldest rocks in the South China Block occur within the Kongling Complex, which yields zircon U–Pb ages of 3.3–2.9 Ga. There are three important reasons to study the South China Block. First, South China hosts a great deal of rare- earth element (REE) ores. Second, the South China Block is a key component of the Rodinia supercontinent. Therefore, such study helps us understand more about the supercontinent cycle.
Eugène-Anatole Demarçay (1 January 1852, Paris – 5 March 1903, Paris) was a French chemist who designed highly specialized apparatus for use in his research. A specialist in the emerging field of spectroscopy, he detected the presence of the rare earth element europium in 1896, and isolated it as the oxide europia in 1901. He helped Marie Curie to confirm the existence of another new element, radium, in 1898.
Anzaite-(Ce) is a rare-earth element (REE) oxide mineral with the formula Ce4Fe2+Ti6O18(OH)2.Chakhmouradian, A. R., Cooper, M. A., Medici, L., Abdu, Y. A., and Shelukhina, Y. S., 2015. Anzaite-(Ce), a new rare-earth mineral and structure type from the Afrikanda silicocarbonatite, Kola Peninsula, Russia. Mineralogical Magazine 79(5), 1231-1244 An example of chemically related mineral is lucasite-(Ce), although it contains no iron.
The first rare-earth element discovered was the black mineral "ytterbite" (renamed to gadolinite in 1800). It was discovered by Lieutenant Carl Axel Arrhenius in 1787 at a quarry in the village of Ytterby, Sweden. Arrhenius's "ytterbite" reached Johan Gadolin, a Royal Academy of Turku professor, and his analysis yielded an unknown oxide (earth) that he called yttria. Anders Gustav Ekeberg isolated beryllium from the gadolinite but failed to recognize other elements ore contained.
Khanashin, or Khan Neshin, (other names: Khān Neshīn, Khannesin, Khan Nashin, Khān Nashīn, Khan Nashim, Khānnešīn) is a village located in the Reg District of Helmand Province, Afghanistan at at 642 altitude. It is close to the Helmand River and 168 km southwest of Lashkargah. It has been identified by the USGS as the site of a deposit, called the Khanneshin carbonatite, of at least 1 million tons of rare earth element ore.
Tranquillityite forms thin stripes up to 15 by 65 micrometres in size in basaltic rocks, where it was produced at a late crystallization stage. It is associated with troilite, pyroxferroite, cristobalite and alkali feldspar. The mineral is nearly opaque and appears dark red-brown in thin crystals. The analyzed samples contain less than 10% impurities (Y, Al, Mn, Cr, Nb and other rare- earth element) and up to 0.01% (100 ppm) of uranium.
Lutetium is a rare-earth element, with one naturally-occurring stable isotope 175Lu and one naturally-occurring radioactive isotope 176Lu. When 176Lu atoms are incorporated into earth materials, such as rocks and minerals, they began to be "trapped" while starting to decay. Through radioactive decay, an unstable nucleus decays into another relatively stable one. Radiometric dating makes use of the decay relationship to calculate how long the atoms have been "trapped", i.e.
This has been used to study the extracellular matrix in pancreatic tissue and porcine tissue. Armani is interested in using optical devices for epigenetic investigations, and has developed a label-free sensor that can detect and quantify DNA methylation. The sensor incorporates a rare-earth element optical cavity to form a nanolaser. The heterodyned nanolaser sensors can be used to diagnose ovarian cancer as they are sensitive to RASSF1A and BRCA1 promoters.
Yttrium is a chemical element with the symbol Y and atomic number 39. It is a silvery-metallic transition metal chemically similar to the lanthanides and has often been classified as a "rare-earth element". Yttrium is almost always found in combination with lanthanide elements in rare-earth minerals, and is never found in nature as a free element. 89Y is the only stable isotope, and the only isotope found in the Earth's crust.
Neodymium was discovered in 1885 by the Austrian chemist Carl Auer von Welsbach. It is present in significant quantities in the ore minerals monazite and bastnäsite. Neodymium is not found naturally in metallic form or unmixed with other lanthanides, and it is usually refined for general use. Although neodymium is classed as a rare-earth element, it is fairly common, no rarer than cobalt, nickel, or copper, and is widely distributed in the Earth's crust.
Holmium(III) oxide, or holmium oxide is a chemical compound of a rare-earth element holmium and oxygen with the formula Ho2O3. Together with dysprosium(III) oxide (Dy2O3), holmium oxide is one of the most powerfully paramagnetic substances known. The oxide, also called holmia, occurs as a component of the related erbium oxide mineral called erbia. Typically, the oxides of the trivalent lanthanides coexist in nature, and separation of these components requires specialized methods.
The volcanic crater is distinct, and has erupted in historical times, only "blocky" lava flows. Charles Wood and Jürgen Kienle, volcanologists, propose that earlier activity, 4,000–5,000 years ago, consisted primarily of lavas of ethereal (fine) platy and thick andesite. Amak Volcano is unique in that its andesitic lavas, while composed the same as the other Aleutians, contain an abundance of potash. They also could contain more sodium carbonate and rare-earth element deposits than the Aleutian norm.
Gadolinium is a silvery-white, malleable, ductile rare-earth element. It crystallizes in the hexagonal close- packed α-form at room temperature, but, when heated to temperatures above , it transforms into its β-form, which has a body-centered cubic structure. The isotope gadolinium-157 has the highest thermal-neutron capture cross-section among any stable nuclide: about 259,000 barns. Only xenon-135 has a higher capture cross-section, about 2.0 million barns, but this isotope is radioactive.
Hundreds of thousands of gallons of water carrying radioactive waste from rare earth element mining spilled into and around Ivanpah Dry Lake.Lisa Margonelli, Clean Energy's Dirty Little Secret, "The Atlantic", May 2009. In the 1980s, the Mountain Pass rare earth mine began piping wastewater as far as 14 miles to evaporation ponds on or near Ivanpah Dry Lake, east of Interstate 15 near Nevada. This pipeline repeatedly ruptured during cleaning operations to remove mineral deposits called scale.
SiAlON gear (right) prepared from a billet (left) by forging at 1200 °C within 2 seconds. SiAlONs are produced by first combining a mixture of raw materials including silicon nitride, alumina, aluminium nitride, silica and the oxide of a rare-earth element such as yttrium. The powder mix is fabricated into a "green" compact by isostatic powder compaction or slipcasting, for example. Then the shaped form is densified, typically by pressureless sintering or hot isostatic pressing.
Erbium is a chemical element with the symbol Er and atomic number 68. A silvery-white solid metal when artificially isolated, natural erbium is always found in chemical combination with other elements. It is a lanthanide, a rare earth element, originally found in the gadolinite mine in Ytterby in Sweden, from which it got its name. Erbium's principal uses involve its pink-colored Er3+ ions, which have optical fluorescent properties particularly useful in certain laser applications.
Perovskites have a more or less cubic structure with general formula of . In this structure, an A-site ion, on the corners of the lattice, is usually an alkaline earth or rare-earth element. B-site ions, on the center of the lattice, could be 3d, 4d, and 5d transition metal elements. A large number of metallic elements are stable in the perovskite structure, if the Goldschmidt's tolerance factor t is in the range of 0.75–1.0.
Older domes have higher amphibole and lower quartz content than younger domes. Post-caldera domes are strongly hydrothermally altered. Rocks from Incapillo are rich in sodium and have high ratios of lanthanum and samarium to ytterbium and high ratios of barium to lanthanum, as well as high lead-206 to lead-204 and strontium-87/strontium-86 ratios. These rare-earth element patterns are similar to the Late Miocene Maricunga Belt rocks and contrast to early Miocene rocks.
In 1794, after careful chemical analysis, Gadolin reported that approximately 38% of the sample was a previously unknown "earth". (The idea of chemical element was not yet established.) The compound that Gadolin isolated, the first rare-earth metal compound, is now known as Yttrium(III) oxide. It is composed of the first known rare-earth element, yttrium. Examining a different sample, Anders Gustaf Ekeberg confirmed the existence of a new "earth", calling it "yttria" and the source mineral "ytterbite".
Gadolinite was named in 1800 for Johan Gadolin, the Finnish mineralogist- chemist who first isolated an oxide of the rare-earth element yttrium from the mineral in 1792. The rare earth gadolinium was also named for him. However, gadolinite does not contain more than trace amounts of gadolinium. When Gadolin analyzed this mineral, he missed an opportunity to discover a second element: the element he thought was aluminium (alumina) was in fact beryllium (beryllia), an element that was not officially identified until 1798.
Lanthanum has a low to moderate level of toxicity and should be handled with care. The injection of lanthanum solutions produces hyperglycemia, low blood pressure, degeneration of the spleen and hepatic alterations. The application in carbon arc light led to the exposure of people to rare earth element oxides and fluorides, which sometimes led to pneumoconiosis. As the La3+ ion is similar in size to the Ca2+ ion, it is sometimes used as an easily traced substitute for the latter in medical studies.
In glass, there are optical fiber cables that amplify the light pulses at regular intervals, using glass doped with the rare-earth element erbium. The doped glass is spliced into the fiber and pumped by a laser operating at a different frequency. In plastic, field effect transistors are being made with polythiophene, a polymer invented by Alan J. Heeger et al. that becomes an electrical conductor when oxidized. By 2016, a factor of just 20 in electron mobility separated plastic from silicon.
The magmatic evolution of the flood basalts show evidence of different parental magmas, fractionation, and open system processes. Mafic tholeittic samples model N-MORB magmas from a depleted mantle source and likely experienced a small amount of crustal contamination in the form of light rare earth element enriched, crust-derived melt. The presence of MORB-like rocks could indicate that an asthenospheric mantle source was important in west-central Madagascar. Some mafic rocks of transitional-alkaline composition fractionated to evolved basaltic composition.
The postglacial activity appears to originate from a shallow silicic magma chamber beneath the caldera. Research published in 2017 indicates that this system is somewhat heterogeneous with distinct compositions of magmas erupted in the northwesterly and southeasterly parts of the volcanic field. The early post-glacial rhyodacites contain mafic inclusions implying that mafic lavas exist but do not reach the surface. From isotope ratios it has been inferred that the magma is of deep origin, and the rare-earth element composition shows no evidence of crustal contamination.
The use of X-ray spectra (obtained by X-ray crystallography) by Henry Gwyn Jeffreys Moseley made it possible to assign atomic numbers to the elements. Moseley found that the exact number of lanthanides had to be 15, and that element 61 had yet to be discovered. Using these facts about atomic numbers from X-ray crystallography, Moseley also showed that hafnium (element 72) would not be a rare-earth element. Moseley was killed in World War I in 1915, years before hafnium was discovered.
Another additive of REE mining that contributes to REE environmental contamination is cerium oxide () which is produced during the combustion of diesel and is released as an exhaust particulate matter and contributes heavily to soil and water contamination. False-color satellite image of the Bayan Obo Mining District, 2006 Mining, refining, and recycling of rare earths have serious environmental consequences if not properly managed. A potential hazard could be low-level radioactive tailings resulting from the occurrence of thorium and uranium in rare-earth element ores.Bourzac, Katherine.
Unlike one sided subduction where only one magmatic arc is generated on the overriding plate, two parallel magmatic arcs are generated on both colliding overriding plates when the oceanic plate subducts on two sides. Volcanic rocks indicating arc volcanism can be found on both sides of the suture zone. Typical rock types include calc-alkaline basalt, andesites, dacite and tuff. These arc volcanic rocks are enriched in Large Ion Lithophile Element (LILE) and Light Rare Earth Element (LREE) but depleted in niobium, hafnium and titanium.
Marinsky was born in Buffalo, New York on April 11, 1918. He attended the University at Buffalo, entering at age 16Jacob Marinsky; co- discoverer of promethium, Associated Press, September 9, 2005 and receiving a bachelor's degree in chemistry in 1939. During World War II he was employed as a chemist for the Manhattan Project, working at Clinton Laboratories (now Oak Ridge National Laboratory) from 1944 to 1946. In 1945, together with Lawrence E. Glendenin and Charles D. Coryell, he isolated the previously undocumented rare earth element 61.
The youngest intrusive rocks based on cross-cutting relations are arfvedsonite granite dikes and sills in the southwestern periphery of the Brandberg massif which crop out in the Amis valley. The arfvedsonite granites contain minerals rich in rare-earth element minerals such as pyrochlore and bastnaesite. Remnants of Cretaceous volcanic rocks are preserved in a collar along the western and southern margins of the massif. Their angle of dip increases towards the contact where clasts of country rock occur within the granite forming a magmatic breccia.
The similarities of yttrium to the lanthanides are so strong that the element has historically been grouped with them as a rare-earth element, and is always found in nature together with them in rare-earth minerals.Emsley 2001, p. 498 Chemically, yttrium resembles those elements more closely than its neighbor in the periodic table, scandium,Daane 1968, p. 810. and if physical properties were plotted against atomic number, it would have an apparent number of 64.5 to 67.5, placing it between the lanthanides gadolinium and erbium.
Neodymium is typically 10–18% of the rare-earth content of commercial deposits of the light rare- earth-element minerals bastnäsite and monazite. With neodymium compounds being the most strongly colored for the trivalent lanthanides, it can occasionally dominate the coloration of rare-earth minerals when competing chromophores are absent. It usually gives a pink coloration. Outstanding examples of this include monazite crystals from the tin deposits in Llallagua, Bolivia; ancylite from Mont Saint-Hilaire, Quebec, Canada; or lanthanite from the Saucon Valley, Pennsylvania, United States.
Other scientists resumed the search for the elusive element 93, which seemed to be straightforward, as they now knew it resulted from the 23-minute half-life. At the Radiation Laboratory in Berkeley, California, Emilio Segrè and Edwin McMillan used the cyclotron to create the isotope. They then detected a beta activity with a 2-day half-life, but it had rare-earth element chemical characteristics, and element 93 was supposed to have chemistry akin to rhenium. It was therefore overlooked as just another fission product.
Rare-earth barium copper oxide (also referred to as ReBCO) is a family of chemical compounds known for exhibiting high temperature superconductivity. ReBCO superconductors have the potential to sustain stronger magnetic fields than other superconductor materials. Due to their stronger magnetic field and relatively high superconducting critical temperature, these materials have been proposed for future magnetic confinement fusion reactors such as the ARC reactor, allowing a more compact and economical construction. Any rare-earth element can be used in a ReBCO; popular choices include yttrium (YBCO), lanthanum (LBCO), samarium, neodymium, and gadolinium.
1992, 618, 35. In going from the binary to ternary systems, some of the transition metal atoms are substituted by a third element, which can be an alkali metal, alkaline earth metal, rare-earth element, main group element, or another transition metal. This leads to an empirical formula of the form A23−xBxC6. Materials of this kind continue to be studied for potentially interesting magnetic and physical properties.Eriksson, T.; Vennström, M.; Ronneteg, S.; Andersson, Y.; Nordblad, P. Complex magnetic properties of Mn3Ni20P6 and ferromagnetic structure of the new isostructural compound Mn3Pd20P6.
Praseodymium always occurs naturally together with the other rare-earth metals. It is the fourth most common rare-earth element, making up 9.1 parts per million of the Earth's crust, an abundance similar to that of boron. In 1841, Swedish chemist Carl Gustav Mosander extracted a rare-earth oxide residue he called didymium from a residue he called "lanthana", in turn separated from cerium salts. In 1885, the Austrian chemist Baron Carl Auer von Welsbach separated didymium into two elements that gave salts of different colours, which he named praseodymium and neodymium.
Abundance of elements in Earth's crust per million Si atoms (y axis is logarithmic) Rare-earth element cerium is actually the 25th most abundant element in Earth's crust, having 68 parts per million (about as common as copper). Only the highly unstable and radioactive promethium "rare earth" is quite scarce. The rare-earth elements are often found together. The longest-lived isotope of promethium has a half-life of 17.7 years, so the element exists in nature in only negligible amounts (approximately 572 g in the entire Earth's crust).
The phosphate minerals are characterized by the tetrahedral [PO4]3− unit, although the structure can be generalized, and phosphorus is replaced by antimony, arsenic, or vanadium. The most common phosphate is the apatite group; common species within this group are fluorapatite (Ca5(PO4)3F), chlorapatite (Ca5(PO4)3Cl) and hydroxylapatite (Ca5(PO4)3(OH)). Minerals in this group are the main crystalline constituents of teeth and bones in vertebrates. The relatively abundant monazite group has a general structure of ATO4, where T is phosphorus or arsenic, and A is often a rare-earth element (REE).
CL-microscopy is used in geology, mineralogy and materials science (rocks, minerals, volcanic ash, glass, ceramic, concrete, fly ash, etc.). More recently, scientists have begun to investigate its application for studying biological samples, using rare earth element-doped inorganic nanocrystals as imaging probes. Correlative Cathodoluminescence Electron Microscopy (CCLEM) can also be performed on focus ion beam (FIB) sectioned samples, hence potentially enabling 3D CCLEM. Hot cathode CL microscope CL color and intensity are dependent on the characteristics of the sample and on the working conditions of the electron gun.
These suggestions were based on Bohr's theories of the atom, the X-ray spectroscopy of Moseley, and the chemical arguments of Friedrich Paneth. Encouraged by these suggestions and by the reappearance in 1922 of Urbain's claims that element 72 was a rare earth element discovered in 1911, Dirk Coster and Georg von Hevesy were motivated to search for the new element in zirconium ores. Hafnium was discovered by the two in 1923 in Copenhagen, Denmark, validating the original 1869 prediction of Mendeleev. It was ultimately found in zircon in Norway through X-ray spectroscopy analysis.
This included new geochemical and geochronometric data for the Baldface Mountain and Satah Mountain volcanic fields, as well as for Nazko Cone. The data obtained indicated that volcanism in the two volcanic fields were contemporaneous with the Itcha Range shield volcano and that both fields agree with the vector of the North American Plate motion over a hotspot in the British Columbia Interior. It was also noted that the trace and rare-earth element patterns of mafic lavas in the Anahim Volcanic Belt are similar to ocean island basalts, providing more evidence for a hotspot.
Near Waratah is a sub-alkaline basalt from an ocean floor, another is a high-magnesium andesite- basalt with chrome spinel and clinoenstatite named boninitic rock after the Bonin Islands. This magma produced the layered pyroxenite dunite in the ultramafic area. Thirdly there is a low titanium basalt-andesite with extreme light rare-earth element depletion that produced the layered pyroxenite- peridotite and associated gabbro cumulate. Two kinds of basalt from the Birchs Inlet–Mainwaring River Volcanics, occur in a belt north from Veridian Point and west of the south end of Birchs Inlet.
Norra Kärr was discovered a few years earlier during regional geological maping by the Swedish Geological Survey. The complex derives its name from a local farm, which translates into English as "Northern Fen". In 1968 Harry von Eckermann published his investigations on the complex defining its boundaries and confirming the view of it as an intrusion. A study has shown that the elevated rare-earth element concentrations in the bedrock in the Norra Kärr area are particularly well reflected in high contents of these elements in the fern Dryopteris filix-mas.
Working with Glenn Seaborg, Segrè isolated the metastable isotope technetium-99m. Its properties made it ideal for use in nuclear medicine, and it is now used in about 10 million medical diagnostic procedures annually. Segrè went looking for element 93, but did not find it, as he was looking for an element chemically akin to rhenium instead of a rare-earth element, which is what element 93 was. Working with Alexander Langsdorf, Jr., and Chien- Shiung Wu, he discovered xenon-135, which later became important as a nuclear poison in nuclear reactors.
Gadolin became famous for his description of the first rare-earth element, yttrium. In 1792 Gadolin received a sample of black, heavy mineral found in a quarry in a Swedish village Ytterby near Stockholm by Carl Axel Arrhenius. By careful experiments, Gadolin determined that approximately 38% of the sample was a previously unknown "earth", an oxide which was later named yttria. Yttria, or yttrium oxide, was the first known rare-earth metal compound—at that time, it was not yet regarded as an element in the modern sense.
Argillization of primary minerals enriches insoluble elements by leaching out silica and other soluble elements, recrystallizing feldspar into clay minerals such kaolinite, halloysite and montmorillonite. In tropical regions where precipitation is high, weathering forms a thick argillized regolith, this process is called supergene enrichment and produces laterite deposits; heavy rare-earth elements are incorporated into the residual clay by absorption. This kind of deposit is only mined for REE in Southern China, where the majority of global heavy rare-earth element production occurs. REE-laterites do form elsewhere, including over the carbonatite at Mount Weld in Australia.
The production of permanent magnets used in some wind turbines makes use of neodymium. Pollution concerns associated with the extraction of this rare- earth element, which is primarily exported by China, have prompted government action in recent years, and international research attempts to refine the extraction process. Research is underway on turbine and generator designs which reduce the need for neodymium, or eliminate the use of rare-earth metals altogether. Additionally, the large wind turbine manufacturer Enercon GmbH chose very early not to use permanent magnets for its direct drive turbines, to avoid responsibility for the adverse environmental impact of rare-earth mining.
Titone was born and raised in the Hudson Valley region of New York. Titone attended the State University of New York at New Paltz from 1996 to 2002 where she earned bachelor's degrees in Geology and Physics.Marianne Goodland, Meet Brianna Titone, Colorado’s first transgender lawmaker, November 24, 2018, The Gazette She later earned a master's degree in Geochemistry at Stony Brook University, and another master's degree in information and communications technology from the University of Denver. At Stony Brook, her master's thesis was on Rare-earth element and Thorium speciation of fossils and sediments of the Green River Formation.
The ridge is primarily composed of mid- ocean ridge basalt, which erupted on the Nazca Plate when the plate was already 5-13 Ma old. Based on isotopic ratios and rare earth element composition, it is estimated that the magma was sourced at approximately 95 km depth from a 7% partial melt. The Nazca Ridge has a conjugate feature on the Pacific Plate, the Tuamotu Plateau. Magnetic anomalies have shown that there was symmetrical spreading at the Pacific-Farallon/Nazca center, so the Tuamotu Plateau can be used as a proxy for the pre-subducted Nazca Ridge geometry.
Ytterbium is a soft, malleable and ductile chemical element that displays a bright silvery luster when pure. It is a rare earth element, and it is readily dissolved by the strong mineral acids. It reacts slowly with cold water and it oxidizes slowly in air. Ytterbium has three allotropes labeled by the Greek letters alpha, beta and gamma; their transformation temperatures are −13 °C and 795 °C, although the exact transformation temperature depends on the pressure and stress. The beta allotrope (6.966 g/cm3) exists at room temperature, and it has a face-centered cubic crystal structure.
Then, these dopant atoms actually carry out the lasing process in the crystal. The rest of the atoms in the crystal consist of yttrium, aluminium, and oxygen atoms, but just as above, these other three elements function to simply support the neodymium atoms. In addition, the rare-earth element erbium can readily be used as the dopant rather than neodymium, giving a different wavelength of its output. In many optically-transparent hosts, such active centers may keep their excitation for a time on the order of milliseconds, and relax with stimulated emission, providing the laser action.
They can be categorised alternatively into three or four groups based on their rare-earth element content.The SNC meteorites: basaltic igneous processes on Mars, Bridges & Warren 2006 These two classification systems do not line up with each other, hinting at complex relationships between the various source rocks and magmas from which the shergottites formed. NWA 6963,NWA 6963 a shergottite found in Morocco, September 2011. The shergottites appear to have crystallised as recently as 180 million years ago, which is a surprisingly young age considering how ancient the majority of the surface of Mars appears to be, and the small size of Mars itself.
Hafnium had been predicted by Dmitri Mendeleev in 1869 and Henry Moseley measured in 1914 the effective nuclear charge by X-ray spectroscopy to be 72, placing it between the already known elements lutetium and tantalum. Dirk Coster and Georg von Hevesy were the first to search for the new element in zirconium ores. Hafnium was discovered by the two in 1923 in Copenhagen, Denmark, validating the original 1869 prediction of Mendeleev. There has been some controversy surrounding the discovery of hafnium and the extent to which Coster and Hevesy were guided by Bohr's prediction that hafnium would be a transition metal rather than a rare earth element.
Klaproth characterised uranium and zirconium as distinct elements, though he did not obtain any of them in the pure metallic state. Klaproth independently discovered cerium (1803), a rare earth element, around the same time as Jöns Jacob Berzelius and Wilhelm Hisinger, in the winter of 1803. William Gregor of Cornwall was the first to identify the element titanium in 1791, correctly concluding that he had found a new element in the ore ilmenite from the Menachan valley. He proposed the name "menachanite", but his discovery attracted little attention. Klaproth verified the presence of an oxide of an unknown element in the ore rutile from Hungary in 1795.
In the 1990s, the PNRI identified the occurrence of Rare-earth element (REE) deposits in the northwestern part of Palawan through earlier geo-chemical surveys and studies. Considered as strategic minerals, REEs are supportive elements in the production of electronics and in the renewable energy industry. From 2013-2016, The PNRI undertook a project that was a combined verification stream sediment and radiometric survey to identify and recommend a detailed evaluation of prospective sites. The collected samples were analyzed for REE and Thorium using X-ray fluorescence (XRF) and Uranium determination using Fluorimetry, including Atomic absorption spectroscopy for the other trace elements of economic value.
The rare-earth element dysprosium is required to fabricate many of the advanced electric motors and battery systems in hybrid propulsion systems./ However, nearly all the rare- earth elements in the world come from China, and one analyst believes that an overall increase in Chinese electronics manufacturing may consume this entire supply by 2012. In addition, export quotas on Chinese rare-earth exports have resulted in a generally shaky supply of those metals. A few non-Chinese sources such as the advanced Hoidas Lake project in northern Canada and Mt Weld in Australia were under development, however it is not known if these sources will be developed before a shortage hits.
Charles James (27 April 1880 – 10 December 1928) was a chemist of British origin working in the United States. He became a professor and head of the chemistry department at the New Hampshire College of Agriculture and the Mechanic Arts (now the University of New Hampshire) in Durham, New Hampshire, USA. James developed the James method for the separation and identification of rare-earth elements by fractional precipitation and crystallization, and provided extracted elements to researchers worldwide. James was one of the first scientists to identify element 71, later named lutetium, and believed that he had found the final rare earth element 61, later named promethium.
The determination of atomic numbers also clarified the order of chemically similar rare-earth elements; it was also used to confirm that Georges Urbain's claimed discovery of a new rare-earth element (celtium) was invalid, earning Moseley acclamation for this technique. Swedish physicist Karl Siegbahn continued Moseley's work for elements heavier than gold (Z = 79), and found that the heaviest known element at the time, uranium, had atomic number 92. In determining the largest identified atomic number, gaps in the atomic number sequence were conclusively determined where an atomic number had no known corresponding element; the gaps occurred at atomic numbers 43, 61, 72, 75, 85, and 87.
The European Union's ETN-Demeter project (European Training Network for the Design and Recycling of Rare-Earth Permanent Magnet Motors and Generators in Hybrid and Full Electric Vehicles) is examining sustainable design of electric motors used in vehicles. They are, for example, designing electric motors in which the magnets can be easily removed for recycling the rare earth metals. The European Union's European Research Council also awarded to Principal Investigator, Prof. Thomas Zemb, and co-Principal Investigator, Dr. Jean- Christophe P. Gabriel, an Advanced Research Grant for the project "Rare Earth Element reCYCling with Low harmful Emissions : REE-CYCLE", which aimed at finding new processes for the recycling of rare earth.
Many scientist are currently working to see if this massive eruption caused a global cooling event. Some scientists are working with conodonts from the rock units surrounding the bentonite layers to see if there is a shift in the rare-earth element concentrations. If there is a shift in the concentration of certain elements then that could potentially correlate to a shift from a tropical marine system to a cold marine system. Also sample localities could effect these concentrations so it is crucial that researchers gather samples from all over the country where the bentonite beds have been confirmed to be from the Deicke eruption.
However, owing to wide current use, "lanthanide" is still allowed and is roughly analogous to rare earth element. According to chemistry professor Andrea Sella, rare-earth elements differ from other elements, insofar that "rare-earth metals, when looked at anatomically, seem to be inseparable from each other, in that they are all almost exactly the same in terms of their chemical properties. However, in terms of their electronic properties, their magnetic properties, each one is really exquisitely unique, and so it can occupy a tiny niche in our technology, where virtually nothing else can."Professor of Chemistry at University College London, Andrea Sella, , Interview on TRT World / Oct 2016, minutes 4:40 - ff.
A piece of cuprate of bismuth and strontium: this piece is a cube with an edge of nearly 1 mm. Bismuth strontium calcium copper oxide (BSCCO, pronounced bisko), is a type of cuprate superconductor having the generalized chemical formula Bi2Sr2Can−1CunO2n+4+x, with n = 2 being the most commonly studied compound (though n = 1 and n = 3 have also received significant attention). Discovered as a general class in 1988, BSCCO was the first high-temperature superconductor which did not contain a rare-earth element. It is a cuprate superconductor, an important category of high-temperature superconductors sharing a two-dimensional layered (perovskite) structure (see figure at right) with superconductivity taking place in a copper-oxide plane.
The Hubbard model can therefore explain the transition from metal to insulator in certain interacting systems. For example, it has been used to describe metal oxides as they are heated, where the corresponding increase in nearest- neighbor spacing reduces the hopping integral to the point where the on-site potential is dominant. Similarly, the Hubbard model can explain the transition from conductor to insulator in systems such as rare-earth pyrochlores as the atomic number of the rare-earth metal increases, because the lattice parameter increases (or the angle between atoms can also change – see Crystal structure) as the rare-earth element atomic number increases, thus changing the relative importance of the hopping integral compared to the on-site repulsion.
Public Hearing Transcript February 19, 2013 - Yellowknife, NECHALACHO RARE EARTH ELEMENT PROJECT - EA1011-001 [2010] The North Slave Métis Alliance (NSMA) has been registered as a non-profit society in the Northwest Territories since 1996. The organization exists for the stated purpose of negotiating a regionally based comprehensive claim centred in the North Slave Region of the Northwest Territories. Prior to 1996, their members were represented in the 1975-1990 Dene-Métis Comprehensive Claim negotiation process by the Métis Nation of the Northwest Territories (MNNWT), which was formed in 1972 to represent all indigenous Métis in the Northwest Territories. This organisation was disbanded after the Final Agreement was rejected, and the pan-territorial process was abandoned in favor of the pursuit of regional claims.
Common technology for plug-ins and electric cars is based on the lithium-ion battery and an electric motor which uses rare-earth elements. The demand for lithium, heavy metals, and other specific elements (such as neodymium, boron and cobalt) required for the batteries and powertrain is expected to grow significantly due to the future sales increase of plug-in electric vehicles in the mid and long term. , the Toyota Prius battery contains more than of the rare-earth element lanthanum, and its motor magnets use neodymium and dysprosium. While only of lithium carbonate equivalent (LCE) are required in a smartphone and in a tablet computer, electric vehicles and stationary energy storage systems for homes, businesses or industry use much more lithium in their batteries.
Common technology for plug-in hybrids and electric cars is based on the lithium-ion battery and an electric motor which uses rare-earth elements. The demand for lithium and other specific elements (such as neodymium, boron and cobalt) required for the batteries and powertrain is expected to grow significantly due to the future sales increase of plug-in electric vehicles in the mid and long term. , the Toyota Prius battery contains more than of the rare-earth element lanthanum, and its motor magnets use neodymium and dysprosium. While only of lithium carbonate equivalent (LCE) are required in a smartphone and in a tablet computer, electric vehicles and stationary energy storage systems for homes, businesses or industry use much more lithium in their batteries.
A CD-RW (CD). Amorphous chalcogenide materials form the basis of re-writable CD and DVD solid-state memory technology. Uses include infrared detectors, mouldable infrared optics such as lenses, and infrared optical fibers, with the main advantage being that these materials transmit across a wide range of the infrared electromagnetic spectrum. The physical properties of chalcogenide glasses (high refractive index, low phonon energy, high nonlinearity) also make them ideal for incorporation into lasers, planar optics, photonic integrated circuits, and other active devices especially if doped with rare-earth element ions. Some chalcogenide glasses exhibit several non-linear optical effects such as photon-induced refraction,Tanaka, K. and Shimakawa, K. (2009), Chalcogenide glasses in Japan: A review on photoinduced phenomena. Phys. Status Solidi B, 246: 1744–1757.
Zircon, a common target for Lu–Hf analysis Lutetium–hafnium dating is a geochronological dating method utilizing the radioactive decay system of lutetium–176 to hafnium–176. With a commonly accepted half-life of 37.1 billion years, the long-living Lu–Hf decay pair survives through geological time scales, thus is useful in geological studies. Due to chemical properties of the two elements, namely their valences and ionic radii, Lu is usually found in trace amount in rare-earth element loving minerals, such as garnet and phosphates, while Hf is usually found in trace amount in zirconium-rich minerals, such as zircon, baddeleyite and zirkelite. The trace concentration of the Lu and Hf in earth materials posed some technological difficulties in using Lu–Hf dating extensively in the 1980s.
Her research activities mainly concerned the use of SIMS for the quantitative measurement of low-concentration constituents, of light (Lithium, Beryllium and Boron) and volatile elements (Hydrogen, Fluorine, Chlorine, Carbon) in geological samples, with particular reference to the investigation of the physical/chemical processes underlying the production of secondary ions, aiming at overcoming the limitations of the technique (interferences and non- linear effects, “matrix effects”); the development, set up and optimization of SIMS procedures for trace elements,AN ION PROBE CONTRIBUTION TO RARE-EARTH ELEMENT INVESTIGATION OF GABBRO GOG-1 USING SECONDARY ION MASS-SPECTROMETRY light and volatile elements, and ultra-trace elements in the frame of petrologic, geochemical and crystal-chemical studies, with particular reference to the investigation of melt inclusions, silicate minerals, artificial glasses, chemically-complex silicate and non-silicate matrixes, experimental charges.
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).
Greta J. Orris and Richard I. Grauch Rare Earth Element Mines, Deposits, and Occurrences , USGS, 2002 The 3T polytype was originally found in the Poudrette quarry at Mont Saint-Hilaire, which is a rare alkaline intrusive complex.Haring, Monika Characterization and crystal-structure determination of UK 117 and UK 120, two potentially new minerals from Mont Saint-Hilaire, Québec, B.Sc. Thesis, Laurentian University, 2010 The 2H polytype is pleochroic, meaning that the mineral changes colors (in this case yellow and light yellow) when viewed at different angles under a polarizing petrographic microscope. The 3T polytype, however, is not commonly pleochroic but can show green pleochroism if it is high in iron. The 3T polytype has a positive index of refraction whereas the 2H polytype can possess crystals with either a positive or a negative index of refraction.
Glauconite, a major component of greensand, is also a common source of potassium (K) in plant fertilizers and is also used to adjust soil pH. It is used for soil conditioning in both organic and nonorganic farming, whether as an unprocessed material (for mixing in at proper proportions) or as a feedstock in the synthesis of commercial fertilizer powders. In Brazil, greensand refers to a fertilizer produced from glauconitic siltstone, unit belonging to the Serra da Saudade Formation, Bambuí Group, of Neoproterozoic/Ediacaran age. The outcrops occur in the Serra da Saudade ridge, in the Alto Paranaíba region, Minas Gerais state. It is a silty-clayed sedimentary rock, laminated, bluish-green, composed of glauconite (40-80%), potassium feldspar (10-15%), quartz (10-60%), muscovite (5%) and minor quantities of biotite (2%), goethite (<1%), titanium and manganese oxides (<1%), barium phosphate and rare-earth element phosphates (<1%).
Rare-earth element abundances of basalts, of both terrestrial and lunar origins The Europium anomaly is the phenomenon whereby the europium (Eu) concentration in a mineral is either enriched or depleted relative to some standard, commonly a chondrite or mid-ocean ridge basalt (MORB). In geochemistry a europium anomaly is said to be "positive" if the Eu concentration in the mineral is enriched relative to the other rare-earth elements (REEs), and is said to be "negative" if Eu is depleted relative to the other REEs. While all lanthanides form relatively large trivalent (3+) ions, Eu and cerium (Ce) have additional valences, europium forms 2+ ions, and Ce forms 4+ ions, leading to chemical reaction differences in how these ions can partition versus the 3+ REEs. In the case of Eu, its reduced divalent (2+) cations are similar in size and carry the same charge as Ca2+, an ion found in plagioclase and other minerals.
Grande Comore is the youngest island and is still volcanically active. Karthala, a shield volcano occupying some two thirds of the island, rises to 2361 meters. The summit caldera is quite large, being approximately 3 x 4 km (1.9 x 2.5 miles) in size at the rim (2007).GlobalVolcanism Program: Karthala Esson J., M.F.J., Flower, D.F. Strong, B.G.J. Upton, and W.J. Wadsworth, Geology of the Comores archipelago western Indian Ocean Geological Magazine 107 (6) 549-557 1970 Flower, M.F.J., Evidence for the role of phlogopite in the genesis of alkali basalts Contrib. Mineral. Petrol. 32 (2) 126-137 1971 Flower, M.F.J., Rare earth element distribution in lavas and ultramafic xenoliths from the Comores archipelago, western Indian Ocean Contributions to Mineralogy and Petrology 31 (4) 335-346 1971 Flower, M.F.J., R N Thompson, One-atmosphere melting and crystallization relations of lavas from Anjouan Comores Archipelago western Indian Ocean Earth and Planetary Science Letters 12 (1) 97-107 1971 Flower, M.F.J., Petrology of volcanic rocks from Anjouan Comores archipelago, Bull, volcanol., 36 (1) 238-250 1973 Flower, M.F.J., Evolution of basaltic and differentiated lavas from Anjouan Comores Archipelago, Contrib. Mineral. Petrol.
The cerium anomaly, in geochemistry, is the phenomenon whereby cerium (Ce) concentration is either depleted or enriched in a rock relative to the other rare-earth elements (REEs). A Ce anomaly is said to be "negative" if Ce is depleted relative to the other REEs and is said to be "positive" if Ce is enriched relative to the other REEs. Cerium is a rare-earth element (lanthanide) characterized by two different redox states: III and IV. Contrary to other lanthanide elements, which are only trivalent (with the notable exception of Eu2+), Ce3+ can be oxidized by atmospheric oxygen (O2) to Ce4+ under alkaline conditions. The cerium anomaly relates to the decrease in solubility, which accompanies the oxidation of Ce(III) to Ce(IV). Under reducing conditions, Ce3+ is relatively soluble, while under oxidizing conditions CeO2 precipitates. Sediments deposited under oxic or anoxic conditions can preserve on the long term the geochemical signature of Ce3+ or Ce4+ upon reserve that no early diagenetic transformation altered it. Cerium can occur in nature as a 3+ or 4+ ion and is a compatible element (at 4+ valency) in zircon and less commonly in silica. Thomas et al.
In 1973, Akira Hasegawa and Fred Tappert of AT&T; Bell Labs were the first to suggest that solitons could exist in optical fibres, due to a balance between self-phase modulation and anomalous dispersion. Also in 1973 Robin Bullough made the first mathematical report of the existence of optical solitons. He also proposed the idea of a soliton-based transmission system to increase performance of optical telecommunications. Solitons in a fibre optic system are described by the Manakov equations. In 1987, P. Emplit, J.P. Hamaide, F. Reynaud, C. Froehly and A. Barthelemy, from the Universities of Brussels and Limoges, made the first experimental observation of the propagation of a dark soliton, in an optical fiber. In 1988, Linn Mollenauer and his team transmitted soliton pulses over 4,000 kilometres using a phenomenon called the Raman effect, named for the Indian scientist Sir C. V. Raman who first described it in the 1920s, to provide optical gain in the fibre. In 1991, a Bell Labs research team transmitted solitons error-free at 2.5 gigabits over more than 14,000 kilometres, using erbium optical fibre amplifiers (spliced-in segments of optical fibre containing the rare earth element erbium). Pump lasers, coupled to the optical amplifiers, activate the erbium, which energizes the light pulses.

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