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Pion correlations as a function of atomic mass in heavy ion collisions

Description: The method of two pion interferometry was used to obtain source-size and lifetime parameters for the pions produced in heavy ion collisions. The systems used were 1.70 {center dot} A GeV {sup 56}Fe + Fe, 1.82 {center dot} A GeV {sup 40}Ar + KCl and 1.54 {center dot} A GeV {sup 93}Nb + Nb, allowing for a search for dependences on the atomic number. Two acceptances (centered, in the lab., at {approximately} 0{degrees} and 45{degrees}) were used for each system, allowing a search for dependences o… more
Date: November 26, 1989
Creator: Chacon, A.D.
Partner: UNT Libraries Government Documents Department
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Tank 241-BY-105 rotary core sampling and analysis plan

Description: This Sampling and Analysis Plan (SAP) identifies characterization objectives pertaining to sample collection, laboratory analytical evaluation, and reporting requirements for two rotary-mode core samples from tank 241-BY-105 (BY-105).
Date: October 26, 1995
Creator: Sasaki, L.M.
Partner: UNT Libraries Government Documents Department
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Final Report: Analysis of Tank 41h Saltcake Sample {number_sign} 2 and Comparison to Sample {number_sign}1

Description: Three saltcake samples taken from Tank 41H on July 12-13, 1993 have been analyzed for chemical and radiochemical content, identification of crystalline phases, and solubility in inhibited water and compared to the results for the earlier sample taken in March 1993.
Date: January 26, 1994
Creator: Hobbs, D. T. & Coleman, C. J.
Partner: UNT Libraries Government Documents Department
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Anion exchange separation of plutonium from various solutions stored at PFP

Description: Nitrate anion exchange has been demonstrated to effectively separate plutonium from other metals in solution. Specific PFP solutions types will be tested to determine if they are suitable candidates for anion exchange. Reillex HPQ resin is used to separate Pu(IV) from nitric acid solutions.
Date: February 26, 1996
Creator: Jones, S.A.
Partner: UNT Libraries Government Documents Department
open access

The transuranium elements: From neptunium and plutonium to element 112

Description: Beginning in the 1930`s, both chemists and physicists became interested in synthesizing new artificial elements. The first transuranium element, Np, was synthesized in 1940. Over the past six decades, 20 transuranium elements have been produced. A review of the synthesis is given. The procedure of naming the heavy elements is also discussed. It appears feasible to produce elements 113 and 114. With the Berkeley Gas-filled Separator, it should be possible to reach the superheavy elements in the … more
Date: July 26, 1996
Creator: Hoffman, D.C.
Partner: UNT Libraries Government Documents Department
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Ion and Neutral Species in C(2)F(6) and CHF(3) Dielectric Etch Discharges

Description: Relative concentrations of reactive ions, neutral radicals, resist and substrate etch products have been measured in dielectric etch chemistries using an uncollided beam mass spectrometer / ion extractor from Hiden Analytical. Analysis techniques employed include both electron impact ionization and dissociative ionization of neutral gas, and potential bias extraction of positive ions from the reactor discharge volume. Measurements were made in C{sub 2}F{sub 6} and CHF{sub 3} discharges in an in… more
Date: January 26, 1999
Creator: Hebner, G.; Jayaraman, R.P. & McGrath, R.T.
Partner: UNT Libraries Government Documents Department
open access

Workshop for coordinating South Carolina`s pre-college systemic initiatives

Description: The goal of the South Carolina Statewide Systemic Initiative (SC SSI) is to provide quality and effective learning experiences in science and mathematics to all people of South Carolina by affecting systemic change. To accomplish this goal, South Carolina must: (1) coordinate actions among many partners for science and mathematics change; (2) place the instruments of change into the hands of the effectors of change - teachers and schools; and (3) galvanize the support of policy makers, parents,… more
Date: March 26, 1997
Partner: UNT Libraries Government Documents Department
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Research on computed tomography reconstructions from one or two radiographs: A report and the application to FXR radiography

Description: This report documents some cooperative research into volumetric image reconstruction from single radiographs. Imaging dynamic events is the most important application for this type of work, but the techniques have possible extensions. Two general objectives guide this work. The first objective is to gain an understanding of the assumptions and limitations of single-view methods for representing internal features. Second, we endeavor to obtain and/or develop techniques for performing image recon… more
Date: January 26, 1995
Creator: Back, N.; Schneberk, D.; McMillan, C.; Azevedo, S. & Gorvad, M.
Partner: UNT Libraries Government Documents Department
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X-ray, K-edge measurement of uranium concentration in reactor fuel plates

Description: Under the Characterization, Monitoring, and Sensor Technology Crosscutting Program, the authors have designed and built a K-edge heavy-metal detector that measures the level of heavy-metal content inside closed containers in a nondestructive, non-invasive way. They have applied this technique to measurement of the amount of uranium in stacks of reactor fuel plates containing nuclear materials of different enrichments and alloys. They have obtained good agreement with expected uranium concentrat… more
Date: November 26, 1997
Creator: Jensen, T.; Aljundi, T.; Whitmore, C.; Zhong, H. & Gray, J.N.
Partner: UNT Libraries Government Documents Department
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Studies of supported hydrodesulfurization catalysts. Final technical report

Description: This report describes a series of studies on the following: Mo/titania and Mo/alumina catalysts for thiophene hydrodesulfurization; absorption of metal oxyanion on alumina; particle size effects for Co/silica catalyst for CO hydrogenation; correlation of Mo oxidation states with benzene hydrogenation activity; factor analysis for curve fitting Mo ESCA spectra; and quantitative Raman and ESCA characterization of W/titania catalysts. 27 refs.
Date: October 26, 1995
Creator: Hercules, D. M.
Partner: UNT Libraries Government Documents Department
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Tank 241-BY-103 headspace gas and vapor characterization results for samples collected in May 1994 and November 1994

Description: Significant changes have been made to all of the original vapor characterization reports. This report documents specific headspace gas and vapor characterization results for all vapor sampling events to date. In addition, changes have been made to the original vapor reports to qualify the data based on quality assurance issues associated with the performing laboratories
Date: September 26, 1995
Creator: Bratzel, D.R.
Partner: UNT Libraries Government Documents Department
open access

An experimental method for investigating phase transformations in the heat affected zone of welds using synchrotron radiation

Description: Although welding is an established technology used in many industrial settings, it is least understand terms of the phases that actually exist, the variation of their spatial disposition with time, and the rate of transformation from one phase to another at various thermal coordinates in the vicinity of the weld. With the availability of high flux and, more recently, high brightness synchrotron x-radiation sources, a number of diffraction and spectroscopic methods have been developed for struct… more
Date: May 26, 1995
Creator: Elmer, J.W.; Wong, J.; Froba, M.; Waide, P.A. & Larson, E.M.
Partner: UNT Libraries Government Documents Department
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The hydrothermal stability of cement sealing materials in the potential Yucca Mountain high level nuclear waste repository

Description: Cementitious materials, together with other materials, are being considered to seal a potential repository at Yucca Mountain. A concern with cementitious materials is the chemical and mineralogic changes that may occur as these materials age while in contact with local ground waters. A combined theoretical and experimental approach was taken to determine the ability to theoretically predict mineralogic changes. The cementitious material selected for study has a relatively low Ca:Si ratio approa… more
Date: November 26, 1991
Creator: Krumhansl, J. L.; Hinkebein, T. E. & Myers, J.
Partner: UNT Libraries Government Documents Department
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Effect of tetralin on polymer degradation in solution. [Quarterly report, January--March 1995]

Description: The effect of a hydrogen-donor solvent (tetralin) on the thermal degradation of poly(styrene-allyl alcohol) in solution was investigated in a steady-state tubular flow reactor at 1000 psig (6.8 MPa), at various tetralin concentrations (0--50%), polymer concentrations (1--4 g/L), and temperatures (130--200 C). The molecular weight distributions of the effluent at each condition were examined as a function of residence time by gel permeation chromatography. In the presence of tetralin, the polyme… more
Date: April 26, 1995
Creator: Madras, G.; Smith, J. M. & McCoy, B. J.
Partner: UNT Libraries Government Documents Department
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Thermal decomposition of UO{sub 3}-2H{sub 2}0

Description: The first part of the report summarizes the literature data regarding the uranium trioxide water system. In the second part, the experimental aspects are presented. An experimental program has been set up to determine the steps and species involved in decomposition of uranium oxide di-hydrate. Particular attention has been paid to determine both loss of free water (moisture in the fuel) and loss of chemically bound water (decomposition of hydrates). The influence of water pressure on decomposit… more
Date: February 26, 1998
Creator: Flament, T.A.
Partner: UNT Libraries Government Documents Department
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Oxidation of Coal and Coal Pyrite Mechanisms and Influence on Surface Characteristics. Final Report

Description: Coal oxidation has been studies extensively in previous work. However, there is still no general agreement concerning the mechanisms of oxidation. Moreover, the oxidation behavior of coal and mineral matter have generally been regarded as separate processed. There is appreciable evidence that organic and inorganic oxidation process are actually coupled, consequently the changes in their surface properties induced by oxidation are difficult to predict. This makes the effectively of coal cleaning… more
Date: January 26, 1996
Creator: Doyle, F. M.
Partner: UNT Libraries Government Documents Department
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Thermal chemical-mechanical reactive flow model of shock initiation in solid explosives

Description: The three dimensional Arbitrary Lagrange Eulerian hydrodynamic computer code ALE3D with fully coupled thermal-chemical-mechanical material models provides the framework for the development of a physically realistic model of shock initiation and detonation of solid explosives. The processes of hot spot formation during shock compression, subsequent ignition of reaction or failure to react, growth of reaction in individual hot spots, and coalescence of reacting hot spots during the transition to … more
Date: August 26, 1998
Creator: Nicholls, A. L., III & Tarver, C. M.
Partner: UNT Libraries Government Documents Department
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