Muchos somos tan afortunados que damos por sentadas las emociones más sublimes.
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When Io peeks out from behind Jupiter once more, the frozen sulfur dioxide warms and sublimes back to its gaseous state.
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Instead, the particles could be tossed into the air when nitrogen ice sublimes—turns from a solid into a gas, creating an upward jet of nitrogen gas.
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It is a colorless solid that readily sublimes into intensely yellow vapors.
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Dicoronylene sublimes under high vacuum, 0.001 torr, between 250 °C and 300 °C.
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Acetylene is also the only other common industrial gas that sublimes at atmospheric pressure.
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However, adamantane slowly sublimes even at room temperature. Adamantane can be distilled with water vapor.
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Gold(III) fluoride, , is an orange solid that sublimes at 300 °C., p. 1184. It is a powerful fluorinating agent.
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Zeitschrift für Kristallographie, 38, 147–148. Above 13 °C (55 °F), almost pure cryptohalite emerges. Bararite sublimes without leaving residue.
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Arsenic triiodide is the inorganic compound with the formula AsI3. It is a dark red solid that readily sublimes. It is a pyramidal molecule that is useful for preparing organoarsenic compounds.
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Francisco Gabriel Junqueira, Baron of Alfenas, began breeding his imported Lusitano to the mares on his farm (primarily Barbs, along with other breeds brought to Brazil when it was colonized). The result was a smooth-gaited, attractive horse which the baron called Sublime. Junqueira sold some of the Sublimes to a friend who had a farm in Paty do Alferes, Rio de Janeiro. The farm's name was Mangalarga, and the owner rode Sublimes to and from Rio de Janeiro.
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Arsenic is attacked by nitric acid and concentrated sulfuric acid. It reacts with fused caustic soda to give the arsenate Na3AsO3 and hydrogen gas.Greenwood & Earnshaw 2002, p. 552 Arsenic sublimes at 615 °C.
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Tungsten(VI) oxytetrabromide is the inorganic compound with the formula WOBr4. This a red-brown, hygroscopic solid sublimes at elevated temperatures. It forms adducts with Lewis bases. The solid consists of weakly associated square pyramidal monomers.
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Crystal structure of OsO4 Osmium(VIII) oxide forms monoclinic crystals. It has a characteristic acrid chlorine-like odor. The element name osmium is derived from osme, Greek for odor. OsO4 is volatile: it sublimes at room temperature.
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Naphthalene, an organic compound commonly found in pesticides such as mothballs, sublimes easily because it is made of non- polar molecules that are held together only by van der Waals intermolecular forces. Naphthalene is a solid that sublimes at standard atmospheric temperature with the sublimation point at around 80°C or 176°F. At low temperature, its vapour pressure is high enough, 1mmHg at 53°C, to make the solid form of naphthalene evaporate into gas. On cool surfaces, the naphthalene vapours will solidify to form needle-like crystals.
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Experimental set up for the sublimation reaction of naphthalene Solid naphthalene sublimes and form the crystal-like structure at the bottom of the watch glass Solid compound of naphthalene sublimed to form a crystal-like structure on the cool surface.
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1-Naphthylamine is an aromatic amine derived from naphthalene. It can cause bladder cancer (transitional cell carcinoma). It crystallizes in colorless needles which melt at 50 °C. It possesses a disagreeable odor, sublimes readily, and turns brown on exposure to air.
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Chromocene is the organochromium compound with the formula [Cr(C5H5)2]. Like structurally related metallocenes, chromocene readily sublimes in a vacuum and is soluble in non-polar organic solvents. It is more formally known as bis(η5-cyclopentadienyl)chromium(II).
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It can be prepared by treating basic beryllium carbonate with hot acetic acid. : 2 + 6 AcOH → + 5 + 2 Basic beryllium acetate is insoluble in water but soluble in chloroform, consistent with it being nonpolar. It melts and sublimes in a vacuum without decomposition.
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Triiron dodecarbonyl is the organoiron compound with the formula Fe3(CO)12. It is a dark green solid that sublimes under vacuum. It is soluble in nonpolar organic solvents to give intensely green solutions. Most low-nuclearity clusters are pale yellow or orange.
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Polonium dibromide (also known as polonium(II) bromide) is a chemical compound with the formula PoBr2. This salt is a purple-brown crystalline solid at room temperature. It sublimes (decomposing slightly) at 110 °C/30 μ and decomposes when melted in nitrogen gas at 270–280 °C.
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Decamethylsilicocene Decamethylsilicocene, (C5Me5)2Si, is a group 14 sandwich compound. It is an example of a main-group cyclopentadienyl complex; these molecules are related to metallocenes but contain p-block elements as the central atom. It is a colorless, air sensitive solid that sublimes under vacuum.
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The ridiculously thorough guide to making a MeOH/Water bath. Chemtips.wordpress.com. Retrieved on 2015-02-23. Dry ice sublimes at −78 °C, while liquid nitrogen is used for colder baths. As water or ethylene glycol freeze out of the mixture, the concentration of ethanol/methanol increases.
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Cyclopentadienylthallium, also known as thallium cyclopentadienide, is an organothallium compound with formula C5H5Tl. This light yellow solid is insoluble in most organic solvents, but sublimes readily. It is used as a precursor to transition metal and main group cyclopentadienyl complexes, as well as organic cyclopentadiene derivatives.
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"Water on Mars", April 2004, Physics Today, p. 71. The brilliance of comet tails comes largely from water vapor. On approach to the Sun, the ice many comets carry sublimes to vapor. Knowing a comet's distance from the sun, astronomers may deduce the comet's water content from its brilliance.
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The chemically bound water inside these materials sublimes. During this process, the unexposed side cannot exceed the boiling point of water. Once the hydrates are spent, the temperature on the unexposed side of an endothermic fire barrier tends to rise rapidly. Too much water can be a problem, however.
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In Rio, people noticed the smooth-gaited, attractive Sublimes and began calling them Mangalargas. Breeders and researchers note that until at least 1910, most ranchers involved in the breed's development (especially Junqueira Family members) followed the baron's recommendations to fix the breed's marching gait, hardiness, endurance, health and temperament.
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Titanium perchlorate can be formed by reacting titanium tetrachloride with perchloric acid enriched in dichlorine heptoxide. Another way uses titanium tetrachloride with dichlorine hexoxide. This forms a complex with Cl2O6 which when warmed to 55° in a vacuum, sublimes and can crystallise the pure anhydrous product from the vapour.
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All four trihalides are known. They all contain gallium in the +3 oxidation state. Their proper names are gallium(III) fluoride, gallium(III) chloride, gallium(III) bromide and gallium(III) iodide. ;GaF3 :GaF3 is a white solid which sublimes before it melts, with an estimated melting point above 1000 °C.
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Titanium nitrate is the inorganic compound with formula Ti(NO3)4. It is a colorless, diamagnetic solid that sublimes readily. It is an unusual example of a volatile binary transition metal nitrate. Ill defined species called titanium nitrate are produced upon dissolution of titanium or its oxides in nitric acid.
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Getchellite turns darker red when heated, becoming black by the time it reaches its melting point. Close to this temperature it sublimes (changes directly from a solid to a vapor) and recrystallizes on cooler surfaces as minute acicular black crystals. Melting point: 340 °C to 355 °C. Boiling point: near 470 °C.
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Indigo, space-filling Indigo dye is a dark blue crystalline powder that sublimes at . It is insoluble in water, alcohol, or ether, but soluble in DMSO, chloroform, nitrobenzene, and concentrated sulfuric acid. The chemical formula of indigo is C16H10N2O2. The molecule absorbs light in the orange part of the spectrum (λmax = 613 nm).
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Sorbic acid, or 2,4-hexadienoic acid, is a natural organic compound used as a food preservative. It has the chemical formula CH3(CH)4CO2H. It is a colourless solid that is slightly soluble in water and sublimes readily. It was first isolated from the unripe berries of the Sorbus aucuparia (rowan tree), hence its name.
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Hafnium tetrabromide is the inorganic compound with the formula HfBr4. It is the most common bromide of hafnium. It is a colorless, diamagnetic moisture sensitive solid that sublimes in vacuum.W. Thomas, H. Elias "Darstellung von HfCl4 und HfBr4 durch Umsetzung von Hafnium mit Geschmolzenen Metallhalogeniden" Journal of Inorganic and Nuclear Chemistry 1976, Volume 38, Pages 2227–2229.
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Dry ice subliming in air Solid carbon dioxide (dry ice) sublimes everywhere along the line below the triple point (e.g., at the temperature of −78.5 °C (194.65 K, ) at atmospheric pressure, whereas its melting into liquid CO2 can occur only along the line at pressures and temperatures above the triple point (i.e., 5.2 atm, −56.4 °C).
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The Manhattan Project required the production and handling of uranium hexafluoride for uranium enrichment, whether by diffusion or centrifuge. Uranium hexafluoride is very corrosive, oxidising, volatile solid (sublimes at 56 °C).Uranium Hexafluoride , International Chemical Safety Cards #1250. To handle this material, several new materials were required, including a coolant liquid that could survive contact with uranium hexafluoride.
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Hexamethyltungsten is the chemical compound W(CH3)6 also written WMe6. Classified as a transition metal alkyl complex, hexamethyltungsten is an air- sensitive, red, crystalline solid at room temperature; however, it is extremely volatile and sublimes at −30 °C. Owing to its six methyl groups it is extremely soluble in petroleum, aromatic hydrocarbons, ethers, carbon disulfide, and carbon tetrachloride.
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Crystals of ferrocene after purification by vacuum sublimation Ferrocene is an air- stable orange solid with a camphor-like odor. As expected for a symmetric, uncharged species, ferrocene is soluble in normal organic solvents, such as benzene, but is insoluble in water. It is stable to temperatures as high as 400 °C. Ferrocene readily sublimes, especially upon heating in a vacuum.
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This cooling bath, often used in laboratories, achieves a temperature of −78 °C.Cooling baths – ChemWiki. Chemwiki.ucdavis.edu. Retrieved on 2013-06-17. However, this practice is discouraged due to its safety risks; the solvents are flammable and volatile, and dry ice con cause frostbite (through contact with exposed skin) and suffocation (due to the large volume of carbon dioxide generated when it sublimes).
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Its structure was determined by both NMR spectroscopy and X-ray crystallography in 1963. The structure is square planar, as has been confirmed by neutron diffraction studies, According to VSEPR theory, in addition to four fluoride ligands, the xenon center has two lone pairs of electrons. These lone pairs are mutually trans. Xenon tetrafluoride sublimes at a temperature of 115.7 °C.
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Copper(II) nitrate, Cu(NO3)2, is an inorganic compound that forms a blue crystalline solid. Anhydrous copper nitrate forms deep blue-green crystals and sublimes in a vacuum at 150-200 °C. Copper nitrate also occurs as five different hydrates, the most common ones being the hemipentahydrate and trihydrate. These materials are more commonly encountered in commerce than in the laboratory.
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It is less sensitive than pentaerythritol tetranitrate (PETN). Under normal conditions, RDX has a Figure of Insensitivity of exactly 80 (RDX defines the reference point). RDX sublimes in vacuum, which restricts or prevents its use in some applications. RDX, when exploded in air, has about 1.5 times the explosive energy of TNT per unit weight and about 2.0 times per unit volume.
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Dinitrogen pentoxide is the chemical compound with the formula N2O5, also known as nitrogen pentoxide or nitric anhydride. It is one of the binary nitrogen oxides, a family of compounds that only contain nitrogen and oxygen. It exists as colourless crystals that melt at 41 °C. Its boiling point is 47 °C, and sublimes slightly above room temperature, yielding a colorless gas.
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Zirconium perchlorate is a molecular substance containing zirconium and perchlorate groups with formula Zr(ClO4)4. Zr(ClO4)4 is a volatile crystalline product. It can be formed by reacting zirconium tetrachloride with dry perchloric acid at liquid nitrogen temperatures. Zr(ClO4)4 sublimes slowly in a vacuum at 70°C showing that the molecule is covalently bound rather than being ionic.
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She also created ad campaigns for Thierry Mugler, Lanvin, and Christian Lacroix. Actes Sud also published her book Sublimes, the result of her work in the fashion world in the 1980s and 90s. In 2001, she spent a few years in Saint Petersburg to report on communal apartments. A book of this work, Kommounalki, was published by Actes Sud in 2008.
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Highly anisotropic thermal conductivity has been measured in three major principal crystal orientations and is effected by strain applied across the lattice. Exfoliated black phosphorus sublimes at 400 °C in vacuum. It gradually oxidizes when exposed to water in the presence of oxygen, which is a concern when contemplating it as a material for the manufacture of transistors, for example.
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Pagodane is an organic compound with formula whose carbon skeleton was said to resemble a pagoda, hence the name. It is a polycyclic hydrocarbon whose molecule has the D2h point symmetry group. The compound is a highly crystalline solid that melts at 243 °C, is barely soluble in most organic solvents and moderately soluble in benzene and chloroform. It sublimes at low pressure.
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Monomeric SeO2 is a polar molecule, with the dipole moment of 2.62 D pointed from the midpoint of the two oxygen atoms to the selenium atom. The solid sublimes readily. At very low concentrations the vapour has a revolting odour, resembling decayed horseradishes. At higher concentrations the vapour has an odour resembling horseradish sauce and can burn the nose and throat on inhalation.
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2,4-Dinitrophenol (2,4-DNP or simply DNP) is an organic compound with the formula HOC6H3(NO2)2. It is a yellow, crystalline solid that has a sweet, musty odor. It sublimes, is volatile with steam, and is soluble in most organic solvents as well as aqueous alkaline solutions. When in a dry form, it is a high explosive and has an instantaneous explosion hazard.
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On the other hand, graphite was cheap, actually gets stronger at temperatures up to , and sublimes rather than melts at . Graphite was therefore chosen. To control the reactor, the core was surrounded by control drums coated with graphite or beryllium (a neutron moderator) on one side and boron (a neutron poison) on the other. The reactor's power output could be controlled by rotating the drums.
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Cobaltocene, known also as bis(cyclopentadienyl)cobalt(II) or even "bis Cp cobalt", is an organocobalt compound with the formula Co(C5H5)2. It is a dark purple solid that sublimes readily slightly above room temperature. Cobaltocene was discovered shortly after ferrocene, the first metallocene. Due to the ease with which it reacts with oxygen, the compound must be handled and stored using air-free techniques.
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Napoleon Bonaparte allowed him to go free after he had become First Consul in 1799. He exiled himself to Geneva during the Empire, and to Brussels during the Bourbon Restoration. In 1808 Buonarroti formed a Masonic Lodge, Les Sublimes Maîtres Parfaits, to which only serving freemasons were admitted. Within this lodge he formed an inner circle which he used to further his political dreams and aspirations.
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Perfluorocyclohexane is chemically inert and thermally stable. It is a relatively non-toxic, clear, waxy solid, which has a high vapor pressure and therefore sublimes readily at room temperature. In common with other cyclic perfluorocarbons, perfluoromethylcyclohexane can be detected at extremely low concentrations, making it ideal as a tracer. The molecule predominantly exists in its chair conformation, in which it possesses D3d molecular symmetry.
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Geysers of nitrogen gas were observed by Voyager 2 to spew from the subpolar regions around Triton's southern polar ice cap. A possible explanation of this observed phenomenon is that the sun shines through the transparent layer of nitrogen ice, heating the layers beneath. Nitrogen sublimes and eventually erupts through holes in the upper layer, carrying dust along with it and creating dark streaks.
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It does not ignite in air until heated to 300 °C and is insoluble in all solvents. It is not attacked by alkali and only slowly reacts with halogens. It can be oxidised by nitric acid to phosphoric acid. If it is heated in an atmosphere of inert gas, for example nitrogen or carbon dioxide, it sublimes and the vapour condenses as white phosphorus.
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Other reductants such as K, Na, or CaH2 may be used as well in the reduction of decamethylzincocene to decamethyldizincocene. 650px This complex does not react with Lewis bases such PMe3, PPh3, NEt3, or pyridine nor does it react with H2, CO2, or CO. This compound appears to be indefinitely stable at room temperature (however storage at -20 °C is advised) and sublimes near 70 °C.
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Ferrocene is an organometallic compound with the formula . The molecule consists of two cyclopentadienyl rings bound on opposite sides of a central iron atom. It is an orange solid with a camphor-like odor, that sublimes above room temperature, and is soluble in most organic solvents. It is remarkable for its stability: it is unaffected by air, water, strong bases, and can be heated to 400 °C without decomposition.
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In 2015 Marc Quinn opened an exhibition of new work at White Cube Bermondsey, entitled The Toxic Sublime. It featured new bodies of work that explore the ecological impact of man on nature. ‘The Toxic Sublimes’ are distorted, three dimensional seascapes. Alongside these paintings, a new series of sculptures, cast in stainless steel, including one measuring over 7.5 meters long, form part of a body of work titled Frozen Waves.
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Her buildings were the first grand ones planned for that location. The focal point of the complex was the Djeser-Djeseru or "the Sublime of Sublimes", a colonnaded structure of perfect harmony built nearly one thousand years before the Parthenon. Djeser-Djeseru sits atop a series of terraces that once were graced with lush gardens. Djeser-Djeseru is built into a cliff face that rises sharply above it.
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Chromium(III) fluoride is the name for the inorganic compounds with the chemical formula CrF3 as well as several related hydrates. The compound CrF3 is a green crystalline solid that is insoluble in common solvents, but the coloured hydrates [Cr(H2O)6]F3 and [Cr(H2O)6]F3•3H2O are soluble in water. The trihydrate is green, and the hexahydrate is violet. The anhydrous form sublimes at 1100–1200 °C.
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The planet Mars has two permanent polar ice caps. During a pole's winter, it lies in continuous darkness, chilling the surface and causing the deposition of 25–30% of the atmosphere into slabs of CO2 ice (dry ice). When the poles are again exposed to sunlight, the frozen CO2 sublimes. These seasonal actions transport large amounts of dust and water vapor, giving rise to Earth-like frost and large cirrus clouds.
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The high temperature stability, low vapor pressure, good wear resistance and ability to withstand arc corrosion of rhenium are useful in self-cleaning electrical contacts. In particular, the discharge that occurs during electrical switching oxidizes the contacts. However, rhenium oxide Re2O7 has poor stability (sublimes at ~360 °C) and therefore is removed during the discharge. Rhenium has a high melting point and a low vapor pressure similar to tantalum and tungsten.
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Mars has two permanent polar ice caps. During a pole's winter, it lies in continuous darkness, chilling the surface and causing the deposition of 25–30% of the atmosphere into slabs of CO2 ice (dry ice). When the poles are again exposed to sunlight, the frozen CO2 sublimes. These seasonal actions transport large amounts of dust and water vapor, giving rise to Earth-like frost and large cirrus clouds.
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For structural materials in the reactor, the choice came down to graphite or metals. Of the metals, tungsten emerged as the frontrunner, but it was expensive, hard to fabricate, and had undesirable neutronic properties. To get around its neutronic properties, it was proposed to use tungsten-184, which does not absorb neutrons. Graphite was chosen as it is cheap, gets stronger at temperatures up to , and sublimes rather than melts at .
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This odor can be detected on striking arsenide minerals such as arsenopyrite with a hammer. It burns in oxygen to form arsenic trioxide and arsenic pentoxide, which have the same structure as the more well-known phosphorus compounds, and in fluorine to give arsenic pentafluoride. Arsenic (and some arsenic compounds) sublimes upon heating at atmospheric pressure, converting directly to a gaseous form without an intervening liquid state at . The triple point is 3.63 MPa and .
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It is an insulator with a band gap of about 3.7 eV. alt=Two dull silver clusters of crystalline shards. Arsenic is a grey, metallic looking solid which is stable in dry air but develops a golden bronze patina in moist air, which blackens on further exposure. It has a density of 5.727 g/cm3, and is brittle and moderately hard (MH 3.5; more than aluminium; less than iron). Arsenic sublimes at 615 °C.
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Californium(III) iodide (CfI3) is a lemon- yellow solid that has a rhombohedral structure and sublimes at ~800 °C. Californium(III) oxyfluoride (CfOF) is prepared by hydrolysis of californium(III) fluoride (CfF3) at high temperature. Californium(III) oxychloride (CfOCl) is prepared by hydrolysis of the hydrate of californium(III) chloride at 280–320 °C. Heating the sulfate in air at about 1200 °C and then reducing with hydrogen at 500 °C produces the sesquioxide (Cf2O3).
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Although carbon remains solid at higher temperatures than tungsten, carbon sublimes at atmospheric pressure instead of melting, so it has no melting point. Tungsten has the lowest coefficient of thermal expansion of any pure metal. The low thermal expansion and high melting point and tensile strength of tungsten originate from strong covalent bonds formed between tungsten atoms by the 5d electrons. Alloying small quantities of tungsten with steel greatly increases its toughness.
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HCB is a white crystalline solid that has negligible solubility in water (0.00000002 M) but sparingly soluble in organic solvents. It is most soluble in halogenated solvents like chloroform (approx 0.03 M), less soluble in esters and hydrocarbons (approx 0.020 M), and even less soluble in short chain alcohols (0.002-0.006 M). Its vapour pressure is 1.09×10−5 mmHg (1.45 mPa) at 20 °C. Its flash point is 242 °C and it sublimes at 322 °C.
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Mars's north polar region with ice cap, composite of Viking 1 orbiter images (Courtesy NASA/JPL-Caltech) In addition to Earth, the planet Mars also has polar ice caps. They consist of primarily water-ice with a few percent dust. Frozen carbon dioxide makes up a small permanent portion of the Planum Australe or the South Polar Layered Deposits. In both hemispheres a seasonal carbon dioxide frost deposits in the winter and sublimes during the spring.
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The synthesis of XeF2 is an endothermic process which results in a white powder which sublimes at low pressures. (P < 4 Torr) The low vapor pressure allowed early researchers and engineers to use it in comparatively simple set ups. Modern vapour etch tools are more sophisticated and are characterized by the way the gas is feed into the etch chamber. In pulsed systems the etchant is expanded, feed into the reaction chamber and remains there until it has been consumed by the reaction.
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Magnesocene is a white solid at room temperature. It has a melting point of 176 °C, though at atmospheric pressures it sublimes at 100 °C. Unlike ferrocene, magnesocene displays slight dissociation and subsequent ion association in polar, electron-donating solvents (such as ether and THF). :MgCp2 <=> MgCp+ + Cp- :MgCp2 + MgCp+ <=> Mg2Cp3+ :MgCp2 + Cp- <=> MgCp3- While ferrocene is stable at ambient conditions, magnesocene decomposes rapidly on exposure to oxygen or moisture, and as such must be synthesized and stored under inert conditions.
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Chromium carbonyl, also known as chromium hexacarbonyl, is the chemical compound with the formula Cr(CO)6. At room temperature the solid is stable to air, although it does have a high vapor pressure and sublimes readily. Cr(CO)6 is zerovalent, meaning that Cr has an oxidation state of zero, and it is a homoleptic complex, which means that all the ligands are identical. The complex is octahedral with Cr–C and C–O distances of 1.91 and 1.14 Å, respectively.
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Modern safety precautions recommend storing picric acid wet, to minimize the danger of explosion. Dry picric acid is relatively sensitive to shock and friction, so laboratories that use it store it in bottles under a layer of water, rendering it safe. Glass or plastic bottles are required, as picric acid can easily form metal picrate salts that are even more sensitive and hazardous than the acid itself. Industrially, picric acid is especially hazardous because it is volatile and slowly sublimes even at room temperature.
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Dhu Moraes (born 1953 in Rio de Janeiro), is a Brazilian actress and singer. She started the career using the stage name Dudu Moraes, turning after to use Dhu Moraes. She was member of the vocal group As Frenéticas and also member of the groups Mucamas do Painho and Radio Stars, both consequences of her participations in programs of Chico Anysio, Chico Anysio Show. In the 1970s, beyond having taken part of the producing of the Hair, took part of a group "Sublimes", inspired in The Supremes.
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Even though CO2 (dry ice) also sublimes under the conditions present, it would do so at a rate much faster than observed. On July 31, 2008, NASA announced that Phoenix further confirmed the presence of water ice at its landing site. During the initial heating cycle of a sample, the mass spectrometer detected water vapor when the sample temperature reached . Liquid water cannot exist on the surface of Mars with its present low atmospheric pressure and temperature, except at the lowest elevations for short periods.
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WO2Cl2 is prepared by ligand redistribution reaction from tungsten trioxide and tungsten hexachloride: : 2 WO3 \+ WCl6 -> 3 WO2Cl2 Using a two-zone tube furnace, a vacuum-sealed tube containing these solids is heated to 350 °C. The yellow product sublimes to the cooler end of the reaction tube. No redox occurs in this process. An alternative route highlights the oxophilicity of tungsten: :WCl6 \+ 2 O(Si(CH3)3)2 -> 3 WO2Cl2 \+ 4 ClSi(CH3)3 This reaction, like the preceding one, proceeds via the intermediacy of WOCl4.
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The Curtisite variety is only slightly soluble in hot acetone, amyl acetate, butanol, petroleum ether. The solubility is 0.5% or less in hot carbon bisulfide, carbon tetrachloride, chloroform, diethyl ether, or boiling benzene; about 1.5% in toluene, about 2.5% in xylene, and over 10% in hot aniline. The material purified by repeated recrystallization melts at 360-370 C while turning very black. It sublimes giving very thin iridescent colors. Raman spectroscopy studies indicate that it may be a mixture of complex hydrocarbons including benzonaphthothiophenes (chemical formula: C16H10S) and dinaphthothiophenes (chemical formula: C20H12S).
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The literary sublime, as well as the philosophical, aesthetic sublimes, is inherently connected to nature but, as with most literary terms, the sublime evolved alongside literature. More authors began to connect the natural sublime to an internalized emotion of terror. Authors began to see the sublime, with its inherent contradictions (pain and pleasure, terror and awe) as representative of the changing political and cultural climate of the times. They began to incorporate more aspects of the sublime into their literary works as a way of externalizing their inner conflicts.
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Pellets of "dry ice", a common form of solid carbon dioxide Carbon dioxide is colorless. At low concentrations the gas is odorless; however, at sufficiently-high concentrations, it has a sharp, acidic odor. At standard temperature and pressure, the density of carbon dioxide is around 1.98 kg/m3, about 1.67 times that of air. Carbon dioxide has no liquid state at pressures below . At 1 atmosphere (near mean sea level pressure), the gas deposits directly to a solid at temperatures below and the solid sublimes directly to a gas above −78.5 °C.
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Passing gaseous S4N4 over silver metal wool at 250–300 °C at low pressure (1mm Hg) yields cyclic S2N2. The silver reacts with the sulfur produced by the thermal decomposition of the S4N4 to form Ag2S, and the resulting Ag2S catalyzes the conversion of the remaining S4N4 into the four-membered ring S2N2, :S4N4 \+ 8 Ag → 4 Ag2S + 2 N2 :S4N4 → 2S2N2 An alternative uses the less explosive S4N3Cl. S2N2 decomposes explosively above 30°C, and is shock sensitive. It readily sublimes, and is soluble in diethyl ether.
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On this basis they are estimated to be , respectively. Some experimental evidence suggests astatine may have lower melting and boiling points than those implied by the halogen trend; a chromatographic estimation of the boiling point of elemental astatine in 1982 suggested a boiling point of 503±3 K (about 230±3 °C or 445±5 °F). Astatine sublimes less readily than does iodine, having a lower vapor pressure. Even so, half of a given quantity of astatine will vaporize in approximately an hour if put on a clean glass surface at room temperature.
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When the pressure is below the triple point, solid nitrogen directly sublimes to gas. The triple point is at 63.14±0.06 K and 0.1255±0.0005 bar. The vapour pressure has been measured from 20 K up to the triple point. For α-nitrogen (below 35 K) the logarithm of the pressure is given by 12.40 −807.4 × T−1 −3926 T−2 +6.297×10\+ 4T−3 −4.633× 10 +5T−4 1.325× 10\+ 6T−5. For β-nitrogen it is given by 8.514 −458.4T−1 −19870 T−2 4.800 × 10\+ 5T−3 −4.524 × 10+6T−4.
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Although the temperature on Mars can reach above freezing (), liquid water is unstable over much of the planet, as the atmospheric pressure is below water's triple point and water ice sublimes into water vapor. Exceptions to this are the low-lying areas of the planet, most notably in the Hellas Planitia impact basin, the largest such crater on Mars. It is so deep that the atmospheric pressure at the bottom reaches 1155 Pa, which is above the triple point, so if the temperature exceeded 0 °C liquid water could exist there.
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When this obliquity is high, its poles get much more direct sunlight and heat; this causes the ice caps to warm and become smaller as ice sublimes. Adding to the variability of the climate, the eccentricity of the orbit of Mars changes twice as much as Earth's eccentricity. As the poles sublime, the ice is redeposited closer to the equator, which receive somewhat less solar insolation at these high obliquities. Computer simulations have shown that a 45° tilt of the Martian axis would result in ice accumulation in areas that display glacial landforms.
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Permafrost polygons imaged by the Phoenix lander. The Phoenix lander also confirmed the existence of large amounts of water ice in the northern region of Mars. This finding was predicted by previous orbital data and theory, and was measured from orbit by the Mars Odyssey instruments. On June 19, 2008, NASA announced that dice-sized clumps of bright material in the "Dodo-Goldilocks" trench, dug by the robotic arm, had vaporized over the course of four days, strongly indicating that the bright clumps were composed of water ice that sublimes following exposure.
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The compound is prepared by treating selenium with chlorine. When the reacting selenium is heated, the product sublimes from the reaction flask. The volatility of selenium tetrachloride can be exploited to purification of selenium. Solid SeCl4 is actually a tetrameric cubane-type cluster, for which the Se atom of an SeCl6 octahedron sits on four corners of the cube and the bridging Cl atoms sit on the other four corners. The bridging Se-Cl distances are longer than the terminal Se-Cl distances, but all Cl-Se-Cl angles are approximately 90°.
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The anionic is isotypic to its cerium, uranium, neptunium, and plutonium analogues and has a distorted icosahedral structure. Particularly important is the borohydride, , first prepared in the Manhattan Project along with its uranium(IV) analogue. It is produced as follows: :ThF4 \+ 2 Al(BH4)3 → + 2 AlF2BH4 following which thorium borohydride can be easily isolated, as it sublimes out of the reaction mixture. Like its protactinium(IV) and uranium(IV) analogues, it is a thermally and chemically stable compound where thorium has a coordination number of 14 with a bicapped hexagonal antiprismatic molecular geometry.
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Dry ice pellet subliming in water, releasing thick white fog. UN 1845 label for dry ice Prolonged exposure to dry ice can cause severe skin damage through frostbite, and the fog produced may also hinder attempts to withdraw from contact in a safe manner. Because it sublimes into large quantities of carbon dioxide gas, which could pose a danger of hypercapnia, dry ice should only be exposed to open air in a well- ventilated environment. For this reason, dry ice is assigned the S-phrase in the context of laboratory safety.
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The Lely method produces bulk silicon carbide crystals through the process of sublimation. Silicon carbide powder is loaded into a graphite crucible, which is purged with Argon gas and heated to approximately . The silicon carbide near the outer walls of the crucible sublimes and is deposited on a graphite rod near the center of the crucible, which is at a lower temperature. Several modified versions of the Lely method exist, most commonly the silicon carbide is heated from the bottom end rather than the walls of the crucible, and deposited on the lid.
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All gases can potentially be used as a refrigerant around the temperatures at which they are liquid; for example nitrogen (R728) and methane (R50) are used as refrigerant at cryogenic temperatures. Exceptionally carbon dioxide can be produced as a cold solid known as dry ice, which sublimes as it warms in ambient conditions, the properties of carbon dioxide are such that it cannot be liquid at a pressure below its triple point of 5.1 bar. Acetylene is also supplied differently. Since it is so unstable and explosive, this is supplied as a gas dissolved in acetone within a packing mass in a cylinder.
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Lunar and Planetary Science XLVIII, 2017 Large amounts of water ice exist below the Martian surface, as well as on the surface at the poles, where it is mixed with dry ice, frozen . Significant amounts of water are located at the south pole of Mars, which, if melted, would correspond to a planetwide ocean 5–11 meters deep. Frozen carbon dioxide () at the poles sublimes into the atmosphere during the Martian summers, and small amounts of water residue are left behind, which fast winds sweep off the poles at speeds approaching . This seasonal occurrence transports large amounts of dust and water ice into the atmosphere, forming Earth-like ice clouds.
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Iodine is a chemical element with the symbol I and atomic number 53. The heaviest of the stable halogens, it exists as a lustrous, purple-black non- metallic solid at standard conditions that melts to form a deep violet liquid at 114 degrees Celsius, and boils to a violet gas at 184 degrees Celsius. However, it sublimes easily with gentle heat, resulting in a widespread misconception even taught in some science textbooks that it does not melt. The element was discovered by the French chemist Bernard Courtois in 1811, and was named two years later by Joseph Louis Gay-Lussac, after the Greek ἰώδης "violet-coloured".
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Ablative heat shield (after use) on Apollo 12 capsule The ablative heat shield functions by lifting the hot shock layer gas away from the heat shield's outer wall (creating a cooler boundary layer). The boundary layer comes from blowing of gaseous reaction products from the heat shield material and provides protection against all forms of heat flux. The overall process of reducing the heat flux experienced by the heat shield's outer wall by way of a boundary layer is called blockage. Ablation occurs at two levels in an ablative TPS: the outer surface of the TPS material chars, melts, and sublimes, while the bulk of the TPS material undergoes pyrolysis and expels product gases.
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At room temperatures, has a high vapor pressure, making it useful in the gaseous diffusion process to separate the rare uranium-235 from the common uranium-238 isotope. This compound can be prepared from uranium dioxide and uranium hydride by the following process: : + 4 HF → + 2 (500 °C, endothermic) : + → (350 °C, endothermic) The resulting , a white solid, is highly reactive (by fluorination), easily sublimes (emitting a vapor that behaves as a nearly ideal gas), and is the most volatile compound of uranium known to exist. One method of preparing uranium tetrachloride () is to directly combine chlorine with either uranium metal or uranium hydride. The reduction of by hydrogen produces uranium trichloride () while the higher chlorides of uranium are prepared by reaction with additional chlorine.
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Protactinium(V) fluoride can be prepared by reacting protactinium oxide with either bromine pentafluoride or bromine trifluoride at about 600 °C, and protactinium(IV) fluoride is obtained from the oxide and a mixture of hydrogen and hydrogen fluoride at 600 °C; a large excess of hydrogen is required to remove atmospheric oxygen leaks into the reaction. Protactinium(V) chloride is prepared by reacting protactinium oxide with carbon tetrachloride at temperature of 200–300 °C. The by-products (such as PaOCl3) are removed by fractional sublimation. Reduction of protactinium(V) chloride with hydrogen at about 800 °C yields protactinium(IV) chloride – a yellow-green solid which sublimes in vacuum at 400 °C; it can also be obtained directly from protactinium dioxide by treating it with carbon tetrachloride at 400 °C.
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Recent evidence has suggested that any water on the Martian surface may have been too salty and acidic to support regular terrestrial life. impact glass deposits (green spots) at Alga crater, a possible site for preserved ancient life The lack of a magnetosphere and the extremely thin atmosphere of Mars are a challenge: the planet has little heat transfer across its surface, poor insulation against bombardment of the solar wind and insufficient atmospheric pressure to retain water in a liquid form (water instead sublimes to a gaseous state). Mars is nearly, or perhaps totally, geologically dead; the end of volcanic activity has apparently stopped the recycling of chemicals and minerals between the surface and interior of the planet. In situ investigations have been performed on Mars by the Viking landers, Spirit and Opportunity rovers, Phoenix lander, and Curiosity rover.
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" (A. García Calvo, Análisis de la Sociedad del Bienestar, 2nd ed. Zamora 1995, p. 26). and must therefore be considered a "cheat"."(...) la creencia de que puede uno disfrutar de la riqueza en medio de la miseria (de los otros) sin que la riqueza de uno resulte trasformada [sic] por la miseria que la rodea es una creencia falsa, pero al mismo tiempo fundamental para el manejo y mantenimiento del Desarrollo." (A. García Calvo, Análisis de la Sociedad del Bienestar, 2nd ed. Zamora 1995, p. 31). An essential ingredient of the maintenance of Power and Reality is God, a personage who has assumed many different names (such as the name of Man) in the past,"(...) con el Desarrollo no ha hecho sino avanzar el proceso de las Religiones anteriores, que cada vez tenían que hacer que sus Dioses, para mayor dominio, fuesen más astractos [sic] y sublimes.
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Carbonic acid forms as a by-product of CO2/H2O irradiation, in addition to carbon monoxide and radical species (HCO and CO3). Another route to form carbonic acid is protonation of bicarbonates (HCO3−) with aqueous HCl or HBr. This has to be done at cryogenic conditions to avoid immediate decomposition of H2CO3 to CO2 and H2O. Amorphous H2CO3 forms above 120 K, and crystallization takes place above 200 K to give "β-H2CO3", as determined by infrared spectroscopy. The spectrum of β-H2CO3 agrees very well with the by- product after CO2/H2O irradiation. β-H2CO3 sublimes at 230 - 260 K largely without decomposition. Matrix-isolation infared spectroscopy allows for the recording of single molecules of H2CO3. The fact that the carbonic acid may form by irradiating a solid H2O + CO2 mixture or even by proton-implantation of dry ice alone has given rise to suggestions that H2CO3 might be found in outer space or on Mars, where frozen ices of H2O and CO2 are found, as well as cosmic rays. The surprising stability of sublimed H2CO3 up to rather high- temperatures of 260 K even allows for gas-phase H2CO3, e.g.
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