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Plutonium(III) Fluoride
Plutonium(III) fluoride or plutonium trifluoride is the chemical compound composed of plutonium and fluorine with the formula PuF3. This salt forms violet crystals. Plutonium(III) fluoride has the LaF3 structure where the coordination around the plutonium atoms is complex and usually described as tri-capped trigonal prismatic.Wells A.F. (1984) ''Structural Inorganic Chemistry'' 5th edition Oxford Science Publications . Reactions A plutonium(III) fluoride precipitation method has been investigated as an alternative to the typical plutonium peroxide method of recovering plutonium from solution, such as that from a nuclear reprocessing plant. A 1957 study by the Los Alamos National Laboratory reported a less effective recovery than the traditional method, while a more recent study sponsored by the United States Office of Scientific and Technical Information The Office of Scientific and Technical Information (OSTI) is a component of the Office of Science within the U.S. Depart ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Plutonium(III) Chloride
Plutonium(III) chloride is a chemical compound with the formula PuCl3. This ionic plutonium salt can be prepared by reacting the metal with hydrochloric acid. Structure Plutonium atoms in crystalline PuCl3 are 9 coordinate, and the structure is tricapped trigonal prismatic. It crystallizes as the trihydrate, and forms lavender-blue solutions in water.John H. Burns, J. R. Peterson, J. N. Stevenson: "Crystallographic Studies of some Transuranic Trihalides: 239PuCl3, 244CmBr3, 249BkBr3 and 249CfBr3", ''Journal of Inorganic and Nuclear Chemistry'' 1975, ''37 (3)'', 743–749; . Safety As with all plutonium compounds, it is subject to control under the Nuclear Non-Proliferation Treaty. Due to the radioactivity of plutonium, all of its compounds, PuCl3 included, are warm to the touch. Such contact is not recommended, since touching the material may result in serious injury. References Plutonium(III) compounds Nuclear materials Chlorides Actinide halides {{nuclear-t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Precipitation (chemistry)
In an aqueous solution, precipitation is the "sedimentation of a solid material (a precipitate) from a liquid solution". The solid formed is called the precipitate. In case of an inorganic chemical reaction leading to precipitation, the chemical reagent causing the solid to form is called the precipitant. The clear liquid remaining above the precipitated or the centrifuged solid phase is also called the supernate or supernatant. The notion of precipitation can also be extended to other domains of chemistry (organic chemistry and biochemistry) and even be applied to the solid phases (e.g. metallurgy and alloys) when solid impurities segregation (materials science), segregate from a solid phase. Supersaturation The precipitation of a compound may occur when its concentration exceeds its solubility. This can be due to temperature changes, solvent evaporation, or by mixing solvents. Precipitation occurs more rapidly from a strongly supersaturated solution. The formation of a pr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Plutonium(III) Compounds
Plutonium is a chemical element; it has symbol Pu and atomic number 94. It is a silvery-gray actinide metal that tarnishes when exposed to air, and forms a dull coating when oxidized. The element normally exhibits six allotropes and four oxidation states. It reacts with carbon, halogens, nitrogen, silicon, and hydrogen. When exposed to moist air, it forms oxides and hydrides that can expand the sample up to 70% in volume, which in turn flake off as a powder that is pyrophoric. It is radioactive and can accumulate in bones, which makes the handling of plutonium dangerous. Plutonium was first synthesized and isolated in late 1940 and early 1941, by deuteron bombardment of uranium-238 in the cyclotron at the University of California, Berkeley. First, neptunium-238 (half-life 2.1 days) was synthesized, which then beta-decayed to form the new element with atomic number 94 and atomic weight 238 (half-life 88 years). Since uranium had been named after the planet Uranus and nept ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Office Of Scientific And Technical Information
The Office of Scientific and Technical Information (OSTI) is a component of the Office of Science within the U.S. Department of Energy (DOE). The '' Energy Policy Act'' PL 109–58, Section 982, called out the responsibility of OSTI: "The Secretary, through the Office of Scientific and Technical Information, shall maintain with the Department publicly available collections of scientific and technical information resulting from research, development, demonstration, and commercial applications activities supported by the Department." Resources OSTI provides access to energy, science, and technology information through publicly available web-based systems, with supporting tools and technologies to enable information search, retrieval and re-use. Science information resources freely available for public use *OSTI.GOV - The primary search tool for DOE science, technology, and engineering R&D results and the organizational hub for information about DOE OSTI; *DOE PAGES (DOE Public ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
United States
The United States of America (USA), also known as the United States (U.S.) or America, is a country primarily located in North America. It is a federal republic of 50 U.S. state, states and a federal capital district, Washington, D.C. The 48 contiguous states border Canada to the north and Mexico to the south, with the semi-exclave of Alaska in the northwest and the archipelago of Hawaii in the Pacific Ocean. The United States asserts sovereignty over five Territories of the United States, major island territories and United States Minor Outlying Islands, various uninhabited islands in Oceania and the Caribbean. It is a megadiverse country, with the world's List of countries and dependencies by area, third-largest land area and List of countries and dependencies by population, third-largest population, exceeding 340 million. Its three Metropolitan statistical areas by population, largest metropolitan areas are New York metropolitan area, New York, Greater Los Angeles, Los Angel ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Los Alamos National Laboratory
Los Alamos National Laboratory (often shortened as Los Alamos and LANL) is one of the sixteen research and development Laboratory, laboratories of the United States Department of Energy National Laboratories, United States Department of Energy (DOE), located a short distance northwest of Santa Fe, New Mexico, in the Southwestern United States, American southwest. Best known for its central role in helping develop the First Atomic bomb, first atomic bomb, LANL is one of the world's largest and most advanced scientific institutions. Los Alamos was established in 1943 as Project Y, a top-secret site for designing nuclear weapons under the Manhattan Project during World War II.The site was variously called Los Alamos Laboratory and Los Alamos Scientific Laboratory. Chosen for its remote yet relatively accessible location, it served as the main hub for conducting and coordinating nuclear research, bringing together some of the world's most famous scientists, among them numerous Nobel ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nuclear Reprocessing
Nuclear reprocessing is the chemical separation of fission products and actinides from spent nuclear fuel. Originally, reprocessing was used solely to extract plutonium for producing nuclear weapons. With commercialization of nuclear power, the reprocessed plutonium was recycled back into MOX nuclear fuel for thermal reactors. The reprocessed uranium, also known as the spent fuel material, can in principle also be re-used as fuel, but that is only economical when uranium supply is low and prices are high. Nuclear reprocessing may extend beyond fuel and include the reprocessing of other nuclear reactor material, such as Zircaloy cladding. The high radioactivity of spent nuclear material means that reprocessing must be highly controlled and carefully executed in advanced facilities by specialized personnel. Numerous processes exist, with the chemical based PUREX process dominating. Alternatives include heating to drive off volatile elements, burning via oxidation, and fluoride vola ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Trigonal Crystal System
In crystallography, the hexagonal crystal family is one of the six crystal families, which includes two crystal systems (hexagonal and trigonal) and two lattice systems (hexagonal and rhombohedral). While commonly confused, the trigonal crystal system and the rhombohedral lattice system are not equivalent (see section crystal systems below). In particular, there are crystals that have trigonal symmetry but belong to the hexagonal lattice (such as α-quartz). The hexagonal crystal family consists of the 12 point groups such that at least one of their space groups has the hexagonal lattice as underlying lattice, and is the union of the hexagonal crystal system and the trigonal crystal system. There are 52 space groups associated with it, which are exactly those whose Bravais lattice is either hexagonal or rhombohedral. __TOC__ Lattice systems The hexagonal crystal family consists of two lattice systems: hexagonal and rhombohedral. Each lattice system consists of one Bravais lat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Samarium(III) Fluoride
Samarium(III) fluoride ( Sm F3) is a slightly hygroscopic solid fluoride. Conditions/substances to avoid are: open flame, moisture, strong acids. Preparation Samarium(III) fluoride can be obtained by reacting SmCl3 or Sm2(CO3)3 with 40% hydrofluoric acid: : : Samarium(III) fluoride can also be produced by hydrothermal reaction of samarium nitrate and sodium fluroborate at 200 °C. Properties Chemical Samarium(III) fluoride reacts with some reducing agents at high temperatures to obtain samarium(II) fluoride: : \mathsf : \mathsf Physical At room temperature, samarium(III) fluoride has orthorhombic structure with space group ''Pnma'' – β-YF3 type with lattice constants ''a'' = 666,9 pm, ''b'' = 705,9 pm, ''c'' = 440,5 pm. Above 495 °C, it has the rhombohedral In geometry, a rhombohedron (also called a rhombic hexahedron or, inaccurately, a rhomboid) is a special case of a parallelepiped in which all six faces are congruent rhombus, rhombi. It can be u ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lanthanum(III) Fluoride
Lanthanum trifluoride is a refractory ionic compound of lanthanum and fluorine. The chemical formula is . The LaF3 structure Bonding is ionic with lanthanum highly coordinated. The cation sits at the center of a trigonal prism. Nine fluorine atoms are close: three at the bottom corners of the trigonal prism, three in the faces of the trigonal prism, and three at top corners of the trigonal prism. There are also two fluorides a little further away above and below the prism. The cation can be considered 9-coordinate or 11-coordinate. At 300 K, the structure allows the formation of Schottky defects with an activation energy of 0.07 eV, and free flow of fluoride ions with an activation energy of 0.45 eV, making the crystal unusually electrically conductive. The larger sized rare earth elements (lanthanides), which are those with smaller atomic number, also form trifluorides with the LaF3 structure. Some actinides do as well. Applications This white salt is somet ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chemical Formula
A chemical formula is a way of presenting information about the chemical proportions of atoms that constitute a particular chemical compound or molecule, using chemical element symbols, numbers, and sometimes also other symbols, such as parentheses, dashes, brackets, commas and ''plus'' (+) and ''minus'' (−) signs. These are limited to a single typographic line of symbols, which may include subscripts and superscripts. A chemical formula is not a chemical name since it does not contain any words. Although a chemical formula may imply certain simple chemical structures, it is not the same as a full chemical structural formula. Chemical formulae can fully specify the structure of only the simplest of molecules and chemical substances, and are generally more limited in power than chemical names and structural formulae. The simplest types of chemical formulae are called '' empirical formulae'', which use letters and numbers indicating the numerical ''proportions'' of atoms ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
