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Explosive Chemistry: Simulating the Chemistry of Energetic Materials at Extreme Conditions

Description: In the brief instant of a high-explosive detonation, the shock wave produces a pressure 500,000 times that of the Earth's atmosphere, the detonation wave travels as fast as 10 kilometers per second, and internal temperatures soar up to 5,500 Kelvin. As the shock propagates through the energetic material, the rapid heating coupled with compression that results in almost 30% volume reduction, initiate complex chemical reactions. A dense, highly reactive supercritical fluid is established behind t… more
Date: November 18, 2003
Creator: Reed, E J; Manaa, M R & Fried, L E
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Advances in atmospheric chemistry modeling: the LLNL impact tropospheric/stratospheric chemistry model

Description: We present a unique modeling capability to understand the global distribution of trace gases and aerosols throughout both the troposphere and stratosphere. It includes the ability to simulate tropospheric chemistry that occurs both in the gas phase as well as on the surfaces of solid particles. We have used this capability to analyze observations from particular flight campaigns as well as averaged observed data. Results show the model to accurately simulate the complex chemistry occurring near… more
Date: October 7, 1999
Creator: Rotman, D A & Atherton, C
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Chemistry-Nuclear Chemistry Division. Progress report, October 1980-September 1981

Description: This report describes major progress in the research and development programs pursued by the Chemistry-Nuclear Chemistry Division of the Los Alamos National Laboratory during FY 1981. Topics covered include advanced analytical methods, atmospheric chemistry and transport, biochemistry, biomedical research, medical radioisotopes research, element migration and fixation, nuclear waste isolation research, inorganic and structural chemistry, isotope separation, analysis and applications, the newly … more
Date: May 1, 1982
Creator: Ryan, R.R. (comp.)
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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The single electron chemistry of coals

Description: Our work on single election transfer in coals led us to the knowledge that the energetics of bond cleavage in radical cations is 20-40 kcal/mole lower than the corresponding homolytic bond cleavage energies. Having made excellent progress in the other areas covered by this proposal, we are extending our studies to the investigation of the formation and cleavage reaction of radical cations in coals. The formation of a radical cation requires the transfer of an electron from a neutral molecule to… more
Date: January 18, 1991
Creator: Larsen, J. W. & Kaushal, P.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Chemistry-nuclear chemistry division. Progress report, October 1979-September 1980

Description: This report presents the research and development programs pursued by the Chemistry-Nuclear Chemistry Division of the Los Alamos National Laboratory. Topics covered include advanced analytical methods, atmospheric chemistry and transport, biochemistry, biomedical research, element migration and fixation, inorganic chemistry, isotope separation and analysis, atomic and molecular collisions, molecular spectroscopy, muonic x rays, nuclear cosmochemistry, nuclear structure and reactions, radiochemi… more
Date: May 1, 1981
Creator: Ryan, R.R. (comp.)
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Computational Chemistry for Nuclear Waste Characterization and Processing: Relativistic Quantum Chemistry of Actinides

Description: In the course of the 3 years we have conducted calculations on molecular structures containing actinides, lanthanides, and other heavy elements. Our calculations were done at the relativistically-correct, all-electron, 4-component calculations (DHF, MP2, and CCSD(T)), using density functional theory (DFT) with relativistic effective core potentials (RECPs), and various other methodologies. We studied the ground- and excited state structures, energetics, vibrational frequencies, and NMR, excitat… more
Date: August 2, 2002
Creator: Harrison, Robert J.; Bernholdt, David E.; Bursten, Bruce E.; De Jong, Wibe A.; Dixon, David A.; Dyall, Kenneth G. et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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NCAW feed chemistry: Effect of starting chemistry on melter offgas and iron redox

Description: The Pacific Northwest Laboratory (PNL) Vitrification Technology Development (PVTD) program has been established to develop technology to support immobilization of selected Hanford wastes. The effort of the PVTD program is directed by the U.S. Department of Energy (DOE). This report is part of the effort and focuses on the effect of starting waste chemistry on the vitrification process. The objective of the investigation was the evaluation of the effect of starting chemistry on the cold cap beha… more
Date: March 1, 1995
Creator: Smith, P.A.; Vienna, J.D. & Merz, M.D.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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The single electron chemistry of coals

Description: TCNQ Charge Transfer Complexes with Coals. TCNQ can be readily deposited in coals from pyridine solution. IR spectra of TCNQ and TCNQ in Illinois No. 6 coal are shown in Fig. 1. It is clear that the stretching frequency has been shifted by the full 44 cm[sup [minus]1] caused by the transfer of a single electron. Similar behavior has been observed with a variety of coals, including lignites, subbituminous and a range of bituminous coals. There are two possible explanations for the observed shift… more
Date: July 24, 1990
Creator: Larsen, John W. & Flowers, Robert A., II
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Algorithmic chemistry

Description: In this paper complex adaptive systems are defined by a self- referential loop in which objects encode functions that act back on these objects. A model for this loop is presented. It uses a simple recursive formal language, derived from the lambda-calculus, to provide a semantics that maps character strings into functions that manipulate symbols on strings. The interaction between two functions, or algorithms, is defined naturally within the language through function composition, and results i… more
Date: December 13, 1990
Creator: Fontana, W.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Metallocarboxylate chemistry

Description: Work in the past year has concentrated on completing manuscripts describing the synthesis, isolation and characterization of seven metallocarboxylate anions, M-COOM{prime} (M = CpFe(CO)(PPh{sub 3}) or Cp*Fe(CO)(PPh{sub 3}); M{prime} = alkali metal) and compounds derived from these anions. Four of the anions are hydrated, the others are anhydrous analogs of three of them. The electron-rich metal centers bind CO{sub 2} strongly in all cases; thermolysis occurs through initial hydrolysis to the co… more
Date: January 1, 1990
Creator: Gibson, D.H.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Cluster Chemistry

Description: Metal cluster chemistry is one of the most rapidly developing areas of inorganic and organometallic chemistry. Prior to 1960 only a few metal clusters were well characterized. However, shortly after the early development of boron cluster chemistry, the field of metal cluster chemistry began to grow at a very rapid rate and a structural and a qualitative theoretical understanding of clusters came quickly. Analyzed here is the chemistry and the general significance of clusters with particular emp… more
Date: May 1, 1980
Creator: Muetterties, Earl L.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Chemistry of americium

Description: Essential features of the descriptive chemistry of americium are reviewed. Chapter titles are: discovery, atomic and nuclear properties, collateral reading, production and uses, chemistry in aqueous solution, metal, alloys, and compounds, and, recovery, separation, purification. Author and subject indexes are included. (JCB)
Date: January 1, 1976
Creator: Schulz, W. W.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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PEROXYNITRITE CHEMISTRY

Description: This century old area of research has been experiencing a renaissance during the last decade, with the annual number of publications on the subject increasing from only one in 1990 to nearly 200 in the late-1990s. This renewed interest is stimulated by the discovery of biological roles of nitric oxide, distinguished by the 1998 Nobel prize, and the recognition that the conversion of nitric oxide into peroxynitrite may play major roles in human diseases associated with oxidative stress and in ce… more
Date: November 29, 2000
Creator: Lymar, S. V.
Item Type: Refine your search to only Book
Partner: UNT Libraries Government Documents Department
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Technetium chemistry

Description: Technetium chemistry is a young and developing field. Despite the limited knowledge of its chemistry, technetium is the workhorse for nuclear medicine. Technetium is also a significant environmental concern because it is formed as a byproduct of nuclear weapons production and fission-power generators. Development of new technetium radio-pharmaceuticals and effective environmental control depends strongly upon knowledge of basic technetium chemistry. The authors performed research into the basic… more
Date: April 1996
Creator: Burns, C.; Bryan, J.; Cotton, F.; Ott, K.; Kubas, G.; Haefner, S. et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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CLOUD CHEMISTRY.

Description: Clouds present substantial concentrations of liquid-phase water, which can potentially serve as a medium for dissolution and reaction of atmospheric gases. The important precursors of acid deposition, SO{sub 2} and nitrogen oxides NO and NO{sub 2} are only sparingly soluble in clouds without further oxidation to sulfuric and nitric acids. In the case of SO{sub 2} aqueous-phase reaction with hydrogen peroxide, and to lesser extent ozone, are identified as important processes leading to this oxid… more
Date: March 2001
Creator: Schwartz, S. E.
Item Type: Refine your search to only Book
Partner: UNT Libraries Government Documents Department
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Waste management in an environmental chemistry laboratory. [EG G Idaho's Environmental Chemistry Unit]

Description: The operation of a safe and efficient waste management system in an environmental chemistry laboratory is a technically and administratively challenging task. Such a system must provide a safe working environment, satisfy regulatory requirements, and minimize both waste quantities and handling costs, all without adversely affecting the quality of the laboratory's chemical analysis activities. The waste management system of EG G Idaho's Environmental Chemistry Unit is designed to accomplish the … more
Date: January 1, 1992
Creator: Bennett, J. T. Espinosa, J. M.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Analytical chemistry and measurement science: (What has DOE done for analytical chemistry. )

Description: Over the past forty years, analytical scientists within the DOE complex have had a tremendous impact on the field of analytical chemistry. This paper suggests six ''high impact'' research/development areas that either originated within or were brought to maturity within the DOE laboratories. ''High impact'' means they lead to new subdisciplines or to new ways of doing business. 21 refs.
Date: January 1, 1989
Creator: Shults, W. D.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Analytical Chemistry of the Polyphosphates

Description: Additional data were obtained on the separation of linear polymers from cyclic polymers by precipitation with barium chloride. An unexpected peak was observed in the anion-exchange chromatography of a sodium poly-phosphate of n-bar average degree of polymerization) = 6, and the compound represented by this peak was isolated. An end-group titration of this compound by microtechnique proved unequivocally that it is a cyclic phosphate. Although the identification (number of phosphorus atoms per mo… more
Date: October 17, 1961
Creator: Rieman, W., III & Rothbart, H. L.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Aqueous chemistry of iodine

Description: The chemistry of iodine has been examined in aqueous solutions of pH 6 to 10 containing 2500 ppM boron as H/sub 3/BO/sub 3/ at temperatures up to 150/sup 0/C using absorption spectrophotometry to identify and monitor the iodine species present. Kinetic rate constants for the disproportionation of the HOI intermediate, 3HOI= IO/sub 3//sup -/ + 2I/sup -/ + 3H/sup +/, have been measured as a function of pH even though no direct spectral evidence for HOI itself has been observed. An HOI partition c… more
Date: January 1, 1984
Creator: Toth, L.M.; Pannell, K.D. & Kirkland, O.L.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Array processors in chemistry

Description: The field of attached scientific processors (''array processors'') is surveyed, and an attempt is made to indicate their present and possible future use in computational chemistry. The current commercial products from Floating Point Systems, Inc., Datawest Corporation, and CSP, Inc. are discussed.
Date: January 1, 1980
Creator: Ostlund, N. S.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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