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[Bond selective chemistry beyond the adiabatic approximation]

Description: The adiabatic Born-Oppenheimer potential energy surface approximation is not valid for reaction of a wide variety of energetic materials and organic fuels; coupling between electronic states of reacting species plays a key role in determining the selectivity of the chemical reactions induced. This research program initially studies this coupling in (1) selective C-Br bond fission in 1,3- bromoiodopropane, (2) C-S:S-H bond fission branching in CH[sub 3]SH, and (3) competition between bond fissio… more
Date: February 28, 1993
Creator: Butler, Laurie J.
Partner: UNT Libraries Government Documents Department
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Spectroscopic investigations of small-molecule interactions on metal oxide surfaces. Final report, September 1, 1978-December 31, 1981

Description: Angle integrated and angle resolved ultraviolet photoelectron spectroscopy (UPS and ARPES) and high resolution electron energy loss spectroscopy (HREELS) have been performed on the low index single crystal surfaces of zinc oxide. Study of CO/ZnO shows that the mode of binding is dominated by 5sigma donation from the carbon end of the molecule to the unsaturated surface zinc ion with little ..pi.. backbonding to the CO2..pi..* orbital. This electronic structure is verified by a HREELS study. The… more
Date: June 28, 1982
Creator: Solomon, E. I. & McFeely, F. R.
Partner: UNT Libraries Government Documents Department
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Exact calculations of phase and membrane equilibria for complex fluids by Monte Carlo simulation

Description: The general objective of this project is the investigation of phase equilibria for complex fluids using a novel methodology, Monte Carlo simulation in the Gibbs ensemble. The methodology enables the direct determination of the properties of two coexisting fluid phases (e.g. a liquid at equilibrium with its vapor) from a single computer experiment, and is applicable to multicomponent systems with arbitrary equilibrium constraints imposed. The specific goals of this work are to adapt the Gibbs te… more
Date: August 28, 1990
Creator: Panagiotopoulos, A.Z.
Partner: UNT Libraries Government Documents Department
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Interim report on modeling studies of two-photon isotope separation

Description: The two-photon or two-step dissociation method of laser induced isotope enrichment is being modeled for the HBrNO photochemical system. In the model, H/sup 79/Br is selectively excited by resonance IR laser radiation and then dissociated by uv radiation. Selectively dissociated Br atoms are scavenged to form isotopically enriched BrNO and Br/sub 2/. This model includes all kinetic and absorption processes found to be significant and the time-varying concentrations of any species involved in a s… more
Date: January 28, 1975
Creator: Hwang, W.C.; Badcock, C.C. & Kamada, R.F.
Partner: UNT Libraries Government Documents Department
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Automated atomic absorption spectrophotometer, utilizing a programmable desk calculator

Description: A commercial, double-beam atomic absorption spectrophotometer has been interfaced with a sample changer and a Hewlett-Packard 9810A calculator to yield a completely automated analysis system. The interface electronics can be easily constructed and should be adaptable to any double-beam atomic absorption instrument. The calculator is easily programmed and can be used for general laboratory purposes when not operating the instrument. The automated system has been shown to perform very satisfactor… more
Date: March 28, 1977
Creator: Futrell, T. L. & Morrow, R. W.
Partner: UNT Libraries Government Documents Department
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SALTSTONE 2QCY11 TCLP RESULTS

Description: The Saltstone Production Facility (SPF) receives waste from Tank 50H for treatment. In the second quarter of the 2011 calendar year (2QCY11), Tank 50H accepted transfers of approximately 15 kgal from the Effluent Treatment Project (ETP), approximately 2 kgal from Tank 710 - the H-Canyon General Purpose Evaporator, approximately 63 kgal from the HCanyon Super Kukla campaign, approximately 370 kgal from the Actinide Removal Process/Modular Caustic Side Solvent Extraction Unit (ARP/MCU) Decontamin… more
Date: July 28, 2011
Creator: Eibling, R.
Partner: UNT Libraries Government Documents Department
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ICCK Conference Final Report

Description: The 7th International Conference on Chemical Kinetics (ICCK) was held July 10-14, 2011, at Massachusetts Institute of Technology (MIT), in Cambridge, MA, hosted by Prof. William H. Green of MIT’s Chemical Engineering department. This cross-disciplinary meeting highlighted the importance of fundamental understanding of elementary reactions to the full range of chemical investigations. The specific conference focus was on elementary-step kinetics in both the gas phase and in condensed phase. Th… more
Date: May 28, 2013
Creator: Green, William H.
Partner: UNT Libraries Government Documents Department
open access

Progress report for the enhancement of Radcalc: Isotope database, gamma absorption fractions, and G(H{sub 2}) values

Description: Radcalc is a spreadsheet currently used to calculate the generation of hydrogen gas in low-level radioactive waste containers for purposes of transportation and packaging. Radcalc is being enlarged and expanded. It will be offered as a Windows compatible software and will include some of the following enhancements: extended radionuclide library, updated gamma absorption fractions for an increased number of packages, inclusion of a G(H{sub 2}) value data base, updated transportation information,… more
Date: September 28, 1994
Creator: Green, J. R.
Partner: UNT Libraries Government Documents Department
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Purification of 238Pu Oxide using the Pu Oxalate Process

Description: The Pu oxalate process is used to remove {sup 234}U from aged {sup 238}Pu-enriched PuO{sub 2} ({sup 234}U grows into the PuO{sub 2} material with time from a-decay of {sup 238}Pu). The Pu oxalate process was first used on a mixture of weapons grade PuO{sub 2} with UO{sub 2} to work out the processing parameters. It was then applied to aged {sup 238}Pu-enriched PuO{sub 2} ({sup 238}PuO{sub 2}). The {sup 234}U content of the {sup 238}PuO{sub 2} was reduced from 13.2 wt% to 0.0254 wt%, and the Pu … more
Date: November 28, 2001
Creator: Mew, D A; Krikorian, O H; Dodson, K E & Schmitz, J A
Partner: UNT Libraries Government Documents Department
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Construction of an Improved Bayesian Clutter Suppression Model for Gas Detection

Description: This technical report describes a nonlinear Bayesian Regression model that can be used to estimate effuent concentrations from IR hyperspectral data. As the title implies, the model is constructed to account for background clutter more effectively than current estimators. Although the main objective is to account for background clutter, which is the dominant source of variability in IR data, the model could easily be extended to allow for uncertainties in the atmosphere. The term, "clutter," re… more
Date: October 28, 2002
Creator: Heasler, Patrick G.; Anderson, Kevin K. & Hylden, Jeffrey L.
Partner: UNT Libraries Government Documents Department
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Volatility: Fluorinator Design FV-100, Zr-U Fuel Element Processing Phase

Description: Volatility Pilot Plant Mark III Fluorinator is a doublechamber type vessel, each chamber 2 1/2 ft by 16 in. outside diameter separated by a 5-in. pipe 15 in. long. ASME flanged and dished heads are used for the chamber tops and conical sections with a 60 deg apex angle for the chamber bottoms. A new furnace designed to maintain the complete lower chamber (molten salt+ freeboard) above melt temperature is to eliminate past experiences of salt solidification on the wall, heads, and in or on the i… more
Date: May 28, 1959
Creator: Ruch, J. B.
Partner: UNT Libraries Government Documents Department
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THOREX PILOT PLANT: SYSTEM FOR CONCENTRATING SECOND URANIUM

Description: A system for concentrating uranyl nitrate solutions was designed and installed in the Thorex Pilot Plant. A total of 16,060 g of uranium was concentrated in the system in 68 batch runs. A total of 14,400 g total uranium (14.180 g U/sup 233/) was recovered as product suitable for shipment. Uranium loss to the evaporator condensate was 0.03% of ihe total uranium processed. The material balance across the system was 98.4%. The average concentration of uranium in the evaporator feed solution was 29… more
Date: January 28, 1957
Creator: Albrecht, W.L.
Partner: UNT Libraries Government Documents Department
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Production of Ionium From a Pitchblende Residue

Description: A plant designed for concentrating thorium by extraction from pitchblende residue by use of tributyl phosphate followed by hydrofluoric acid strip is described. The fluoride product is further purified by a solvent extraction flowsheet in hot laboratory equipment. An outline of the chemical technology used in this process is presented. (J.R.D.)
Date: July 28, 1955
Creator: Kuhlman, C. W.; Knecht, W. S. & Piper, R. D.
Partner: UNT Libraries Government Documents Department
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Reduction of Plutonium (VI) to Plutonium(III) and (IV) by Sodium Nitrite

Description: The use of anion exchange for final Pu purification in the Redox facility requires the adjustment of Pa(VI) to Pu(IV). Two methods of reduction were investigated: ferrous sulfamate and nitrite. The ferrous sulfamate method was adopted. Data on reduction of Pu(VI) to Pu(IV) and Pu(III) by nitrite are presented. The reduction by nitrite was found to be dependent on nitrite concentration, temperature, acidity, ferric ion concentration, and time, and it is possible to obtain >90% reduction to Pu… more
Date: October 28, 1963
Creator: Colvin, C. A.
Partner: UNT Libraries Government Documents Department
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Geochemical Data Package for Performance Assessment Calculations Related to the Savannah River Site

Description: The Savannah River Site disposes of certain types of radioactive waste within subsurface-engineered facilities. One of the tools used to establish the capacity of a given site to safely store radioactive waste (i.e., that a site does not exceed its Waste Acceptance Criteria) is the Performance Assessment (PA). The objective of this document is to provide the geochemical values for the PA calculations. This work is being conducted as part of the on-going maintenance program that permits the PA t… more
Date: February 28, 2006
Creator: Kaplan, D
Partner: UNT Libraries Government Documents Department
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Chemical Techinology Division, Unit Operations Section Monthly Progress Report, April 1960

Description: Experiments showed that 30% tributyl phosphate will not extract acid- deficient species of uranyl nitrate. Flooding throughputs for the Mark I stacked- clone contactor ranged from 600 cc/min organic at zero aqueous to 60 cc/min organic at 1950 cc aqueous. A large electronic vibrator of 5000-lb thrust was found somewhat inferior to pneumatic vibration for compacting oxide fuels into stainless-steel tubes. Tests were started on the use of fixed-bed CuO oxidizers for removing hydrogen contaminatio… more
Date: July 28, 1960
Creator: Whatley, M E; Haas, P A; Horton, R W; Ryon, A D; Suddath, J C & Watson, C D
Partner: UNT Libraries Government Documents Department
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Chemical Processing Technology Quarterly Progress Report, July-September 1962

Description: Aqueous zirconium fuel processing studies, directed at adapting the hydrofluoric acid process to continuous dissolution-complexing in order to increase the capacity of the ICPP process, resulted in two successful approaches to the complexing-feed adjustment step. Continuous in-line adjustment (conversion of uranium(IV) to uranium(VI) necessary for extraction) was accomplished in one minute or less at approximately 90 deg C; surges of dissolver product from the operating dissolver up to 1.9 time… more
Date: December 28, 1962
Creator: Bower, J.R. ed.
Partner: UNT Libraries Government Documents Department
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THE DETERMINATION OF NIOBIUM IN URANIUM NIOBIUM ALLOYS

Description: The niobium-uranium alloy is dissolved in hydrofluoric nitric acids and the fluoride removed by fuming sulfuric acid. The niobium is hydrolyzed in an acid-sulfur dioxide medium and converted to niobic oxide by ignition at 900 deg C. The method covers the determination of niobium in niobium-uranium alloys having a niobium content of 8 to 12%. Metals which hydrolyze readily in dilute acid solutions interfere with the determination. (auth)
Date: February 28, 1958
Creator: Goward, G. W.; Reinhold, T. M. & Wiederkehr, V. R.
Partner: UNT Libraries Government Documents Department
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Isotopic Analysis of Boron as Trimethyl Borate

Description: Boron-impregnated polyethylene tape was irradiated in the Engineering Test Reactor Critical Facility to study the effect of boron as a burnable poison in reactor fuel. Isotopic analysis of the boron was performed with a conventional CEC Model 21-103 mass spectrometer. The tape was distilled off and the residual boron was converted to trimethyl borate. The reaction mixture was analyzed without separation. Good precision was obtained with samples containing less than 0.5 mg. boron. Features of th… more
Date: January 28, 1960
Creator: Abernathey, R. M.
Partner: UNT Libraries Government Documents Department
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Emission, Dispersion, Transformation, and Deposition of Asian Particulates Over the Western Pacific Ocean

Description: In this project we developed and applied a coupled three-dimensional meteorology/chemistry/microphysics model to study the patterns of aerosol dispersion and deposition in the western Pacific area; carried out a series of detailed regional aerosol simulations to test the ability of models to treat emission, dispersion and removal processes prior to long-range transport; calculated and analyzed trajectories that originate in Asian dust source regions and reach the Pacific Basin; performed detail… more
Date: February 28, 2005
Creator: Turco, Richard P.
Partner: UNT Libraries Government Documents Department
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ISOTOPE SEPARATION AND ISOTOPE EXCHANGE. A Bibliography with Abstracts

Description: The unclassified literature covering 2498 reports from 1907 through 1957 has been searched for isotopic exchange and isotepic separation reactions involving U and the lighter elements of the periodic chart through atomic number 30. From 1953 to 1957, all elements were included Numerous references to isotope properties, isotopic ratios, and kinetic isotope effects were included. This is a complete revision of TID-3036 (Revised) issued June 4, 1954. An author index is included. (auth)
Date: October 28, 1959
Creator: Begun, G.M.
Partner: UNT Libraries Government Documents Department
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Enhanced Control of PWR Primary Coolant Water Chemistry Using Selective Separation Systems for Recovery and Recycle of Enriched Boric Acid

Description: The objective of this project is to develop systems that will allow for increased nuclear energy production through the use of enriched fuels. The developed systems will allow for the efficient and selective recover of selected isotopes that are additives to power water reactors' primary coolant chemistry for suppression of corrosion attack on reactor materials.
Date: February 28, 2006
Creator: Czerwinski, Ken; Yeamans, Charels; Olander, Don; Raymond, Kenneth; Schroeder, Norman; Robison, Thomas et al.
Partner: UNT Libraries Government Documents Department
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