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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
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
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.
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.
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.
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.
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.
Partner: UNT Libraries Government Documents Department
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Chemistry of intermetallic hydrides

Description: Certain intermetallic hydrides are safe, convenient and inexpensive hydrogen storage compounds. A particular advantage of such compounds is the ease with which their properties can be modified by small changes in alloy composition or preparation. This quality can be exploited to optimize their storage properties for particular applications, e.g. as intermetallic hydride electrodes in batteries. We will be concerned herein with the more important aspects of the thermodynamic and structural princ… more
Date: January 1, 1991
Creator: Reilly, J. J.
Partner: UNT Libraries Government Documents Department
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FLIBE chemistry studies

Description: A 2:1 mixture of LiF and BeF{sub 2} (FLIBE), is a potential tritium breeder material for fusion reactors, in particular, the Advanced Safe Pool Immersed Reactor (ASPIRE). A limited experimental campaign was conducted in an effort to test the postulates of the ASPIRE concept: namely, that MoF{sub 6} is effective in controlling the tritium species by maintaining the FT form and that MoF{sub 6} can serve as a source to plate out Mo on surfaces, thereby making the FLIBE system compatible with the c… more
Date: October 1, 1990
Creator: Clemmer, R.G. (Pacific Northwest Lab., Richland, WA (USA)); Sze, D.K.; Blackburn, P.E.; VanDeventer, E. & Maroni, V.A. (Argonne National Lab., IL (USA))
Partner: UNT Libraries Government Documents Department
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Chemistry at Extreme Conditions

Description: We present equation of state results from impulsively stimulated light scattering (ISLS) experiments conducted in diamond anvil cells on pure supercritical fluids. We have made measurements on fluid H{sub 2}O (water), and CH{sub 3}OH (methanol). Sound speeds measured through ISLS have allowed us to refine existing potential models used in the exponential-6 (EXP-6) detonation product library [Fried, L. E., and Howard, W. M., J. Chem. Phys. 109 (17): 7338-7348 (1998).]. The refined models allow u… more
Date: August 8, 2002
Creator: Zaug, J M; Fried, L E; Abramson, E H; Hansen, D W; Crowhurst, J C & Howard, W M
Partner: UNT Libraries Government Documents Department
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Chemistry of berkelium: a review

Description: Element 97 was first produced in December 1949, by the bombardment of americium-241 with accelerated alpha particles. This new element was named berkelium (Bk) after Berkeley, California, the city of its discovery (Thompson, Ghiorso, and Seaborg, Phys. Rev. 77, 838 (1950); 80, 781 (1950)). In the 36 years since the discovery of Bk, a substantial amount of knowledge concerning the physicochemical properties of this relatively scarce transplutonium element has been acquired. All of the Bk isotope… more
Date: January 1, 1985
Creator: Hobart, D. E. & Peterson, J. R.
Partner: UNT Libraries Government Documents Department
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Physical chemistry and the environment

Description: From the ozone hole and the greenhouse effect to plastics recycling and hazardous waste disposal, society faces a number of issues, the solutions to which require an unprecedented understanding of the properties of molecules. We are coming to realize that the environment is a coupled set of chemical systems, its dynamics determining the welfare of the biosphere and of humans in particular. These chemical systems are governed by fundamental molecular interactions, and they present chemists with … more
Date: August 1, 1994
Creator: Dunning, T. H. Jr.; Garrett, B. C.; Kolb, C. E. Jr.; Shaw, R. W.; Choppin, G. R. & Wagner, A. F.
Partner: UNT Libraries Government Documents Department
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Plutonium chemistry of the ocean

Description: Plutonium is a man-made element whose behavior in the marine environment is inadequately known at present. It has been studied intensively in connection with production of weapons and power sources and has been characterized as an extremely toxic substance. Nevertheless, only a few dozen measurements have been made of concentrations in seawater and in the associated organisms and sediments. The first of these were as recent as 1964. There are reasons to believe its chemical behavior in the ocea… more
Date: December 14, 1972
Creator: Folsom, T.R.
Partner: UNT Libraries Government Documents Department
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Technical basis for hydrogen-water chemistry: Laboratory studies of water chemistry effects on SCC (stress-corrosion-cracking)

Description: The influence of different impurities, viz., oxyacids and several chloride salts, on the stress-corrosion-cracking (SCC) of sensitized Type 304 stainless steel (SS) was investigated in constant-extension-rate-tensile (CERT) tests in 289/sup 0/C water at a low dissolved-oxygen concentration (<5 ppB). Cyclic loading experiments on fatigue precracked fracture-mechanics-type specimens of this material and Type 316NG were also performed at 289/sup 0/C in low-oxygen environments with and without sulf… more
Date: October 1, 1986
Creator: Kassner, T.F.; Ruther, W.E. & Soppet, W.K.
Partner: UNT Libraries Government Documents Department
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Laser diagnostics of materials and chemistry

Description: Several examples are given of the ability of laser-based diagnostic techniques to make noninvasive measurements in hostile environments. Using coherent anti-Stokes Raman scattering both majority and minority species concentrations, as well as temperature, have been measured in the hot, high-pressure, particle-laden stream of a coal gasifier. In addition, numerous toxic and corrosive elements in the gasifier stream have been identified, but not yet quantified. In addition to providing the capabi… more
Date: January 1, 1984
Creator: Hartford, A. Jr.
Partner: UNT Libraries Government Documents Department
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Chemistry and stoichiometry of wood liquefaction

Description: The approximate stoichiometry of liquefaction, from data of two PDU runs and a laboratory run is Wood (100 g) + CO (0.1 - 0.4 Mol) ..-->.. CO/sub 2/ (0.5 - 1.0 Mol) + H/sub 2/O (0.4 - 0.8 Mol) + Product (55 - 64 g). Product includes wood oil, water soluble organics and residues. Water is formed by decomposition, carbon dioxide by decomposition and reduction of wood oxygen by CO. Aqueous products include many carboxylic acids plus a roughly equal percentage of non-acids. The wood oil is divided … more
Date: June 1, 1981
Creator: Davis, H. G.; Kloden, D. J. & Schaleger, L. L.
Partner: UNT Libraries Government Documents Department
open access

Chemistry of combined residual chlorination

Description: The decay of the combined chlorine residual was investigated in this work. Recent concerns about the formation of undesirable compounds such as chloroform with free residual chlorination have focused attention on the alternative use of combined residual chlorination. This work investigates the applicability of reactions proposed to describe the transformations and decay of the combined residual with time. Sodium hypochlorite was added to buffered solutions of ammonia with the chlorine residual … more
Date: January 1, 1982
Creator: Leao, S.F. & Selleck, R.E.
Partner: UNT Libraries Government Documents Department
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High temperatue clay chemistry

Description: Hydrothermal experiments with clays such as sepiolite, attapulgite, saponite, and bentonite are described briefly. Rheological and minerological changes were studied in the clays subjected to hydrothermal treatments with and without the addition of the salts and the hydroxides of Na, K, Ca, and Mg. (MHR)
Date: January 1, 1979
Creator: Guven, N. & Carney, L. L.
Partner: UNT Libraries Government Documents Department
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Frontiers of chemistry for americium and curium

Description: The discoveries of americium and curium were made only after Seaborg had formulated his actinide concept in order to design the chemistry needed to separate them from irradiated /sup 239/Pu targets. Their discoveries thus furnished the first clear-cut evidence that the series exists and justified Seaborg's bold assumption that even though Th and Pa appeared to presage a following 6d series, the pattern established by the periodic table after Cs and Ba would be repeated exactly after Fr and Ra. … more
Date: January 1, 1984
Creator: Keller, O.L. Jr.
Partner: UNT Libraries Government Documents Department
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Role of soot in aerosol chemistry

Description: In order to assess the role of soot in aerosol chemistry, an experimental methodology was developed to determine empirically the soot concentrations in various regions of the United States. These results, when combined with laboratory results on the mechanism and kinetics of SO/sub 2/ oxidation, are used to establish the relative importance of soot-catalyzed SO/sub 2/ oxidation in the atmosphere. The methods used for determining soot concentrations and the experimental results on SO/sub 2/ oxid… more
Date: December 1, 1981
Creator: Novakov, T.
Partner: UNT Libraries Government Documents Department
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Chemistry calculations relating to AIM

Description: This paper describes some single-cell rf-heating and air chemistry computations that are intended to model the conditions of an AIM experiment, either in a laboratory environment or in the atmosphere. For a pulsed mode of rf-induced ionization using repetitive 120-ns pulses with 1-ms separation we examine the relative amounts of power required to sustain ionization in the second and subsequent pulses compared to the first pulse. We also compare power requirements for sustained ionization at a p… more
Date: January 1, 1989
Creator: Zinn, J.; Sutherland, C. D. & Roussel-Dupre', R.
Partner: UNT Libraries Government Documents Department
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Environmental chemistry and cycling processes

Description: Separate abstracts were prepared for the 62 papers presented at the conference. (HLW)
Date: January 1, 1978
Creator: Adriano, D. C. & Brisbin, I. L., Jr.
Partner: UNT Libraries Government Documents Department
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Chemistry and materials in geothermal systems

Description: The development of a geothermal fluid, from its origin as meteoric water precipitating on the earth's surface, as it flows through the soils and rocks of geological formations, to the point where it returns to the surface as a hot spring, geyser, well, etc. is traced. Water of magmatic origin is also included. The tendency of these hydrothermal fluids to form scales by precipitation of a portion of their dissolved solids is noted. A discussion is presented of types of information required for m… more
Date: May 1, 1979
Creator: Miller, R. L.
Partner: UNT Libraries Government Documents Department
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