|
Silex Process
Separation of isotopes by laser excitation (SILEX) is a process under development to enrich uranium on an industrial scale for nuclear reactors. It is strongly suspected that it utilizes laser condensation repression to excite the uranium-235 isotope in uranium hexaflouride (UF6), allowing this lighter molecule to move more rapidly to the outer rim of a gaseous jet and resist condensing compared to the heavier, unexcited 238UF6. This differs greatly from previous methods of laser enrichment explored for their commercial prospects: one using atomic uranium (Atomic Vapor Laser Isotope Separation (AVLIS)) and another molecular method that uses lasers to dissociate a fluorine atom from 235UF6 (Molecular Laser Isotope Separation (MLIS)), allowing the enriched product to precipitate out as a solid. While the Australian company Silex Systems Limited is the most prominent developer of this technology (as part of the Global Laser Enrichment consortium), the acronym SILEX really only refers ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Uranium Hexafluoride
Uranium hexafluoride (), (sometimes called "hex") is an inorganic compound with the formula UF6. Uranium hexafluoride is a volatile white solid that reacts with water, releasing corrosive hydrofluoric acid. The compound reacts mildly with aluminium, forming a thin surface layer of AlF3 that resists any further reaction from the compound. UF6 is used in the process of enriching uranium, which produces fuel for nuclear reactors and nuclear weapons. Preparation Milled uranium ore—U3O8 or "yellowcake"—is dissolved in nitric acid, yielding a solution of uranyl nitrate UO2(NO3)2. Pure uranyl nitrate is obtained by solvent extraction, then treated with ammonia to produce ammonium diuranate ("ADU", (NH4)2U2O7). Reduction with hydrogen gives UO2, which is converted with hydrofluoric acid (HF) to uranium tetrafluoride, UF4. Oxidation with fluorine yields UF6. During nuclear reprocessing, uranium is reacted with chlorine trifluoride to give UF6: :U + 2 ClF3 → UF6 + Cl2 Prope ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
UF6 IR
Uranium hexafluoride (), (sometimes called "hex") is an inorganic compound with the formula UF6. Uranium hexafluoride is a volatile white solid that reacts with water, releasing corrosive hydrofluoric acid. The compound reacts mildly with aluminium, forming a thin surface layer of AlF3 that resists any further reaction from the compound. UF6 is used in the process of enriching uranium, which produces fuel for nuclear reactors and nuclear weapons. Preparation Milled uranium ore—U3O8 or "yellowcake"—is dissolved in nitric acid, yielding a solution of uranyl nitrate UO2(NO3)2. Pure uranyl nitrate is obtained by solvent extraction, then treated with ammonia to produce ammonium diuranate ("ADU", (NH4)2U2O7). Reduction with hydrogen gives UO2, which is converted with hydrofluoric acid (HF) to uranium tetrafluoride, UF4. Oxidation with fluorine yields UF6. During nuclear reprocessing, uranium is reacted with chlorine trifluoride to give UF6: :U + 2 ClF3 → UF6 + Cl2 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Molecular Laser Isotope Separation
Molecular laser isotope separation (MLIS) is a method of isotope separation, where specially tuned lasers are used to separate isotopes of uranium using selective ionization of hyperfine transitions of uranium hexafluoride molecules. It is similar to AVLIS. Its main advantage over AVLIS is low energy consumption and use of uranium hexafluoride instead of vaporized uranium. MLIS was conceived in 1971 at the Los Alamos National Laboratory. MLIS operates in cascade setup, like the gaseous diffusion process. Instead of vaporized uranium as in AVLIS the working medium of the MLIS is uranium hexafluoride which requires a much lower temperature to vaporize. The UF6 gas is mixed with a suitable carrier gas (a noble gas including some hydrogen) which allows the molecules to remain in the gaseous phase after being cooled by expansion through a supersonic de Laval nozzle. A scavenger gas (e.g. methane) is also included in the mixture to bind with the fluorine atoms after they are dissocia ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Atomic Vapor Laser Isotope Separation
Atomic vapor laser isotope separation, or AVLIS, is a method by which specially tuned lasers are used to separate isotopes of uranium using selective ionization of hyperfine transitions. A similar technology, using molecules instead of atoms, is molecular laser isotope separation (MLIS). Natural uranium consists of a large mass of 238U and a much smaller mass of fissile 235U. Traditionally, the 235U is separated from the mass by dissolving it in acid to produce uranium hexafluoride and then using gas centrifuges to separate the isotopes. Each trip through the centrifuge "enriches" the amount of 235U and leaves behind depleted uranium. In contrast, AVLIS produces much higher enrichment in a single step without the need to mix it with acid. The technology could, in principle, also be used for isotope separation of other elements, which is uneconomic outside specialist applications with current non-laser-based technologies for most elements. As the process does not require the fe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chelsie Preston Crayford
Chelsie Florence Preston Crayford (born 1987) is a New Zealand actress. Early life Preston Crayford was born in Wellington to film maker Gaylene Preston and musician Jonathan Crayford. Apart from appearing in a water safety commercial at the age of four, her acting debut was at the age of 13 in the New Zealand-made TV series '' A Twist in the Tale'' starring William Shatner. Several years later, her performance in a stage production was praised by Ian McKellen, encouraging her to pursue an acting career and enrol in the Toi Whakaari national drama school from 2006 to 2008. She graduated in 2008 with a Bachelor of Performing Arts. Career Preston Crayford played a guest role in the soap opera ''Shortland Street'' in 2003, and made her feature film debut in the comedy ''Eagle vs Shark'' in 2007. In 2009, she played a major role in the TV series ''The Cult''. In 2011, she played brothel madam Tilly Devine in the Australian crime drama '' Underbelly: Razor'', a role for which she wo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
The Code (2014 TV Series)
''The Code'' is an Australian drama television program created and produced by Shelley Birse. Developed from a partnership between Playmaker Media and the Australian Broadcasting Corporation, it premiered on ABC1 in Australia on 21 September 2014, and the first season aired through 26 October 2014. Season 2 of ''The Code'' premiered on 1 September 2016, and aired through 6 October 2016. The first six-part series, set in both outback and metropolitan areas of Australia, interweaves several plot lines. The first follows brothers Ned (Dan Spielman) and Jesse Banks (Ashley Zukerman), who publish a video of a mysterious outback accident, and Hani Parande (Adele Perovic), who becomes involved with them. The second follows the accident, which sees teacher Alex Wisham (Lucy Lawless) and policeman Tim Simons (Aaron Pedersen) becoming involved in the personal affairs of accused teenager Clarence Boyd ( Aaron L. McGrath). The third covers Ned's journalism office, managed by Perry Benson ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Australian Broadcasting Corporation
The Australian Broadcasting Corporation (ABC) is the national broadcaster of Australia. It is principally funded by direct grants from the Australian Government and is administered by a government-appointed board. The ABC is a publicly-owned body that is politically independent and fully accountable, with its charter enshrined in legislation, the ''Australian Broadcasting Corporation Act 1983''. ABC Commercial, a profit-making division of the corporation, also helps to generate funding for content provision. The ABC was established as the Australian Broadcasting Commission on 1 July 1932 by an act of federal parliament. It effectively replaced the Australian Broadcasting Company, a private company established in 1924 to provide programming for A-class radio stations. The ABC was given statutory powers that reinforced its independence from the government and enhanced its news-gathering role. Modelled after the British Broadcasting Corporation (BBC), which is funded by a tel ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Executive Order
In the United States, an executive order is a directive by the president of the United States that manages operations of the federal government. The legal or constitutional basis for executive orders has multiple sources. Article Two of the United States Constitution gives presidents broad executive and enforcement authority to use their discretion to determine how to enforce the law or to otherwise manage the resources and staff of the executive branch. The ability to make such orders is also based on expressed or implied Acts of Congress that delegate to the president some degree of discretionary power (delegated legislation).John Contrubis, '' Executive Orders and Proclamations'', CRS Report for Congress #95-722A, March 9, 1999, Pp. 1-2 The vast majority of executive orders are proposed by federal agencies before being issued by the president. Like both legislative statutes and the regulations promulgated by government agencies, executive orders are subject to judicial r ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
United States Atomic Energy Act Of 1954
The Atomic Energy Act of 1954, 42 U.S.C. §§ 2011-2021, 2022-2286i, 2296a-2297h-13, is a United States federal law that covers for the development, regulation, and disposal of nuclear materials and facilities in the United States. It was an amendment to the Atomic Energy Act of 1946 and substantially refined certain aspects of the law, including increased support for the possibility of a civilian nuclear industry. Notably it made it possible for the government to allow private companies to gain technical information (Restricted Data) about nuclear energy production and the production of fissile materials, allowing for greater exchange of information with foreign nations as part of President Dwight D. Eisenhower's Atoms for Peace program, and reversed certain provisions in the 1946 law which had made it impossible to patent processes for generating nuclear energy or fissile materials. The H.R. 9757 legislation was passed by the 83rd U.S. Congressional session and signed into law ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Classified Information
Classified information is material that a government body deems to be sensitive information that must be protected. Access is restricted by law or regulation to particular groups of people with the necessary security clearance and need to know, and mishandling of the material can incur criminal penalties. A formal security clearance is required to view or handle classified material. The clearance process requires a satisfactory background investigation. Documents and other information must be properly marked "by the author" with one of several (hierarchical) levels of sensitivity—e.g. restricted, confidential, secret, and top secret. The choice of level is based on an impact assessment; governments have their own criteria, including how to determine the classification of an information asset and rules on how to protect information classified at each level. This process often includes security clearances for personnel handling the information. Some corporations and non-governm ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Silicon
Silicon is a chemical element with the symbol Si and atomic number 14. It is a hard, brittle crystalline solid with a blue-grey metallic luster, and is a tetravalent metalloid and semiconductor. It is a member of group 14 in the periodic table: carbon is above it; and germanium, tin, lead, and flerovium are below it. It is relatively unreactive. Because of its high chemical affinity for oxygen, it was not until 1823 that Jöns Jakob Berzelius was first able to prepare it and characterize it in pure form. Its oxides form a family of anions known as silicates. Its melting and boiling points of 1414 °C and 3265 °C, respectively, are the second highest among all the metalloids and nonmetals, being surpassed only by boron. Silicon is the eighth most common element in the universe by mass, but very rarely occurs as the pure element in the Earth's crust. It is widely distributed in space in cosmic dusts, planetoids, and planets as various forms of silicon dioxide ( ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carbon
Carbon () is a chemical element with the symbol C and atomic number 6. It is nonmetallic and tetravalent In chemistry, the valence (US spelling) or valency (British spelling) of an element is the measure of its combining capacity with other atoms when it forms chemical compounds or molecules. Description The combining capacity, or affinity of an ...—its atom making four electrons available to form covalent bond, covalent chemical bonds. It belongs to group 14 of the periodic table. Carbon makes up only about 0.025 percent of Earth's crust. Three Isotopes of carbon, isotopes occur naturally, Carbon-12, C and Carbon-13, C being stable, while Carbon-14, C is a radionuclide, decaying with a half-life of about 5,730 years. Carbon is one of the Timeline of chemical element discoveries#Ancient discoveries, few elements known since antiquity. Carbon is the 15th Abundance of elements in Earth's crust, most abundant element in the Earth's crust, and the Abundance of the c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
