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(Environmental investigation of ground water contamination at Wright-Patterson Air Force Base, Ohio)
An environmental investigation of ground water conditions has been undertaken at Wright-Patterson Air Force Base (WPAFB), Ohio to obtain data to assist in the evaluation of a potential removal action to prevent, to the extent practicable, migration of the contaminated ground water across Base boundaries. Field investigations were limited to the central section of the southwestern boundary of Area C and the Springfield Pike boundary of Area B. Further, the study was limited to a maximum depth of 150 feet below grade. Three primary activities of the field investigation were: (1) installation of 22 monitoring wells, (2) collection and analysis of ground water from 71 locations, (3) measurement of ground water elevations at 69 locations. Volatile organic compounds including trichloroethylene, perchloroethylene, and/or vinyl chloride were detected in concentrations exceeding Maximum Contaminant Levels (MCL) at three locations within the Area C investigation area. Ground water at the Springfield Pike boundary of Area B occurs in two primary units, separated by a thicker-than-expected clay layers. One well within Area B was determined to exceed the MCL for trichloroethylene.
Date:
March 1, 1992
Creator:
unknown
System:
The UNT Digital Library
Manual of analytical methods for the Industrial Hygiene Chemistry Laboratory
This Manual is compiled from techniques used in the Industrial Hygiene Chemistry Laboratory of Sandia National Laboratories in Albuquerque, New Mexico. The procedures are similar to those used in other laboratories devoted to industrial hygiene practices. Some of the methods are standard; some, modified to suit our needs; and still others, developed at Sandia. The authors have attempted to present all methods in a simple and concise manner but in sufficient detail to make them readily usable. It is not to be inferred that these methods are universal for any type of sample, but they have been found very reliable for the types of samples mentioned.
Date:
August 1, 1991
Creator:
Greulich, K. A. & Gray, C. E.
System:
The UNT Digital Library
Surfaces and Thin Films Studied by Picosecond Ultrasonics
This research is the study of thin films and interfaces via the use of the picosecond ultrasonic technique. In these experiments ultrasonic waves are excited in a structure by means of a picosecond light pulse ( pump pulse''). The propagation of these waves is detected through the use of a probe light pulse that is time-delayed relative to the pump. This probe pulse measures the change {Delta}R(t) in the optical reflectivity of the structure that occurs because the ultrasonic wave changes the optical properties of the structure. This technique make possible the study of the attenuation and velocity of ultrasonic waves up to much higher frequencies than was previously possible (up to least 500 GHz). In addition, the excellent time-resolution of the method makes it possible to study nanostructures of linear dimensions down to 100 {Angstrom} or less by ultrasonic pulse-echo techniques. 25 refs.
Date:
May 1, 1992
Creator:
Maris, J. H. & Tauc, J.
System:
The UNT Digital Library
Westinghouse Hanford Company waste minimization and pollution prevention awareness program plan
The purpose of this plan is to establish the Westinghouse Hanford Company's Waste Minimization Program. The plan specifies activities and methods that will be employed to reduce the quantity and toxicity of waste generated at Westinghouse Hanford Company (Westinghouse Hanford). It is designed to satisfy the US Department of Energy (DOE) and other legal requirements that are discussed in Subsection C of the section. The Pollution Prevention Awareness Program is included with the Waste Minimization Program as permitted by DOE Order 5400.1 (DOE 1988a). This plan is based on the Hanford Site Waste Minimization and Pollution Prevention Awareness Program Plan, which directs DOE Field Office, Richland contractors to develop and maintain a waste minimization program. This waste minimization program is an organized, comprehensive, and continual effort to systematically reduce waste generation. The Westinghouse Hanford Waste Minimization Program is designed to prevent or minimize pollutant releases to all environmental media from all aspects of Westinghouse Hanford operations and offers increased protection of public health and the environment. 14 refs., 2 figs., 1 tab.
Date:
August 1, 1991
Creator:
Craig, P.A.; Nichols, D.H. & Lindsey, D.W.
System:
The UNT Digital Library
Molecular interactions in dilute supercritical mixtures: Molecular dynamics investigation
We performed a series of molecular dynamics simulations aimed at investigating the nature of the microstructure around solute molecules in a supercritical solvent, in the limit of infinite dilution (no solute-solute interactions). The choice of model system (pyrene in supercritical carbon dioxide) and state conditions (5--20 moles/liter; 37{degrees}C and 75{degrees}C) was done so as to match corresponding fluorescence experiments performed at Georgia Tech. 18 refs., 3 figs.
Date:
January 1, 1991
Creator:
Debenedetti, P.G.
System:
The UNT Digital Library
Writer's Guide for technical procedures
A primary objective throughout the Department of Energy (DOE) complex is that operations be conducted in a deliberate and controlled manner with emphasis upon recognition and maintenance of the facility-specific safety envelope. One critical element of maintaining the safety envelope is procedures. DOE is providing guidance through this and other writer's guides to assist procedure writers across the DOE complex in producing accurate, complete, and usable procedures that promote safe and efficient operations in keeping with such DOE Orders as 5480.19, Conduct of Operations for DOE Facilities'', 5480.5, Safety of Nuclear facilities'', and 5480.6, Safety of Department of Energy-Owned Nuclear Reactors''. This Writer's Guide addresses the content, format, and style of technical procedures (procedures that prescribe production, operation of equipment and facilities, and maintenance activities) and is intended to be applied in a manner appropriate to the individual facility, 15 refs.
Date:
September 1, 1991
Creator:
unknown
System:
The UNT Digital Library
Theoretical study of the structure, energetics, and dynamics of silicon and carbon systems using tight-binding approaches
Semiempirical interatomic potentials are developed for silicon and carbon by modeling the total energy of the system using tight-binding approaches. The parameters of the models were obtained by fitting to results from accurate first-principles Local Density Functional calculations. Applications to the computation of phonons as a function of volume for diamond-structured silicon and carbon and the thermal expansions for silicon and diamond yields results which agree well with experiment. The physical origin of the negative thermal expansion observed in silicon is explained. A tight-binding total energy model is generated capable of describing carbon systems with a variety of atomic coordinations and topologies. The model reproduces the total energy versus volume curves of various carbon polytypes as well as phonons and elastic constants of diamond and graphite. The model has also been used in the molecular-dynamics simulation of the properties of carbon clusters. The calculated ground-state geometries of small clusters (C{sub 2}--C{sub 10}) correlates well with results from accurate quantum chemical calculations, and the structural trend of clusters from C{sub 2} to C{sub 60} are investigated. 67 refs., 19 figs.
Date:
October 25, 1991
Creator:
Xu, Chunhui.
System:
The UNT Digital Library
Thin polymer icemaker development and test program
We have constructed and tested a small device to produce ice in ice/water mixtures using a cold fluid as the heat sink. The device is a flexible heat exchanger constructed from a thin film of a suitable polymer. When filled with circulating liquid coolant the heat exchanger consists of an inflated series of parallel tubes; ice forms on the outside in complementary half cylinders. When the circulation is cut off, gravity drains the coolant and the static head of the water bath crushes the tubes, freeing them from the ice which floats to the surface. Brine circulation is then re-started and the cycle begins again. Here we report recent testing of this device: it makes ice readily under water and easily sheds the semi-cylinders of ice over many cycles of operation. It produces ice at a rate of 10 kg/m{sup 2}-hour. It offers substantial benefits in simplicity and reliability over mechanical harvester ice making systems, and the potential for significant improvements in energy efficiency compared to systems which use a re-heat cycle to harvest the ice. A reliable method of leak detection has been developed. The device should be of substantial value to systems where efficiency and reliability are at …
Date:
August 1, 1991
Creator:
Leigh, R.W. (Pratt Inst., Brooklyn, NY (United States))
System:
The UNT Digital Library
Lattice gaugefixing and other optics in lattice gauge theory
We present results from four projects. In the first, quark and gluon propagators and effective masses and {Delta}I = 1/2 Rule operator matching coefficients are computed numerically in gaugefixed lattice QCD. In the second, the same quantities are evaluated analytically in the strong coupling, N {yields} {infinity} limit. In the third project, the Schwinger model is studied in covariant gauges, where we show that the effective electron mass varies with the gauge parameter and that longitudinal gaugefixing ambiguities affect operator product expansion coefficients (analogous to {Delta}I = 1/2 Rule matching coefficients) determined by matching gauge variant matrix elements. However, we find that matching coefficients even if shifted by the unphysical modes are {xi} invariant. In the fourth project, we show that the strong coupling parallelogram lattice Schwinger model as a different thermodynamic limit than the weak coupling continuum limit. As a function of lattice skewness angle these models span the {Delta} = {minus}1 critical line of 6-vertex models which, in turn, have been identified as c = 1 conformal field theories.
Date:
June 1, 1992
Creator:
Yee, Ken.
System:
The UNT Digital Library
Micro-scale mass-transfer variations during electrodeposition
Results of two studies on micro-scale mass-transfer enhancement are reported: (1) Profiled cross-sections of striated zinc surfaces deposited in laminar channel flow were analyzed with fast-fourier transforms (FFT) to determine preferred striation wavelengths. Striation frequency increases with current density until a minimum separation between striae of 150 {mu}m is reached. Beyond this point, independent of substrate used, striae meld together and form a relatively smooth, nodular deposit. Substrates equipped with artificial micron-sized protrusions result in significantly different macro-morphology in zinc deposits. Micro-patterned electrodes (MPE) with hemispherical protrusions 5 {mu}m in diameter yield thin zinc striae at current densities that ordinarily produce random nodular deposits. MPEs with artificial hemi-cylinders, 2.5 {mu}m in height and spaced 250 {mu}m apart, form striae with a period which matches the spacing of micron-sized ridges. (2) A novel, corrosion-resistant micromosaic electrode was fabricated on a silicon wafer. Measurements of mass-transport enhancement to a vertical micromosaic electrode caused by parallel bubble streams rising inside of the diffusion boundary-layer demonstrated the presence of two co-temporal enhancement mechanisms: surface-renewal increases the limiting current within five bubble diameters of the rising column, while bubble-induced laminar flows cause weaker enhancement over a much broader swath. The enhancement caused by bubble curtains …
Date:
August 1, 1991
Creator:
Sutija, D.P.
System:
The UNT Digital Library
Precision measurement of the direct CP violation parameter. var epsilon. prime /. var epsilon. via the four K yields 2. pi. decay modes and a high sensitivity search for CP violating rare K sub L decays, Task J
This report discusses the progress on the measurement of the direct CP violation parameter {var epsilon}{prime}/{var epsilon} and the rare KL decay. The progress has been as follows: (A) results from the complete E731 data set which was collected in the 1987/88 fixed target run; preparations for and the taking of the data for (B) E773 (CPT symmetry test) and (C) E799 (rare decay study); and finally (D) R D for a new detector to further study {var epsilon}{prime}/{var epsilon} and rate decays.
Date:
April 1, 1992
Creator:
Wah, Yau W.
System:
The UNT Digital Library
Comparative mutagenesis of human cells in vivo and in vitro
This report discusses measuring methods of point mutations; high density cell cultures for low dose studies; measurement and sequence determination of mutations in DNA; the mutational spectra of styrene oxide and ethlyene oxide in TK-6 cells; mutational spectrum of Cr in human lymphoblast cells; mutational spectra of radon in TK-6 cells; and the mutational spectra of smokeless tobacco. (CBS)
Date:
May 1, 1992
Creator:
Thilly, W.G.
System:
The UNT Digital Library
Mechanical strength and stability of lithium aluminate
Pacific Northwest Laboratory (PNL) investigated the strength and resistance to thermal shock of lithium aluminate annular pellets. The room temperature, axial compressive fracture strength of pellets made at Westinghouse Advanced Energy Systems (WAES) varied from 80 to 133 ksi. The strength at 430{degrees}C (806{degrees}F) was to 30 to 40% lower. The strength at 900{degrees}C (1652{degrees}F) showed a wide variation with one measurement near 90 ksi. These strength values are consistent with other data and predictions made in the literature when the grain size and porosity of the microstructure are taken into account. In diametral compression tests, the fracture strengths were much lower due to the existence of tensile stresses in some pellet regions from this type of loading. However, the fracture stresses were still generally higher than those reported in the literature; this fracture resistance probably reflects the better quality of the pellets tested in this study. Measurements on pellets made at PNL indicated lower strengths compared to the WAES material. This strength difference could be accounted for by different processing technologies: material made at PNL was cold-pressed and sintered with high porosity whereas the WAES material was isostatically hot-pressed with high density. Thermal shocking of the material by ramping …
Date:
June 1, 1992
Creator:
Brimhall, J.L.
System:
The UNT Digital Library
Proposed research on advanced accelerator concepts
This report summarizes technical progress and accomplishments during the proposed three-year research on advanced accelerator concepts supported by the Department of Energy under Contract No. DE-FG02-88ER40465. A vigorous theoretical program has been pursued in critical problem areas related to advanced accelerator concepts and the basic equilibrium, stability, and radiation properties of intense charged particle beams. Broadly speaking, our research has made significant contributions in the following three major areas: Investigations of physics issues related to particle acceleration including two-beam accelerators and cyclotron resonance laser (CRL) accelerators; Investigations of RF sources including the free- electron lasers, cyclotron resonance masers, and relativistic magnetrons; Studies of coherent structures in electron plasmas and beams ranging from a low-density, nonrelativistic, pure electron plasma column to high-density, relativistic, non-neutral electron flow in a high-voltage diode. The remainder of this report presents theoretical and computational advances in these areas.
Date:
September 1, 1991
Creator:
Davidson, R.C. & Wurtele, J.S.
System:
The UNT Digital Library
NQR-NMR studies of higher alcohol synthesis Cu-Co catalysts
The primary objective of the project is to examine the relations between the catalytic and magnetic properties of the copper-cobalt higher alcohol synthesis catalysts. We have undertaken to investigate the magnetic character by studying the Nuclear Quadrupole resonance of copper and (Zerofield) Nuclear Magnetic Resonance of cobalt in copper cobalt catalysts.
Date:
December 17, 1991
Creator:
unknown
System:
The UNT Digital Library
FY 1992 task plans for the Hanford Environmental Dose Reconstruction Project
Phase 1 of the HEDR Project was designed to develop and demonstrate a method for estimating radiation doses people may have received from Hanford Site operations since 1944. The method researchers developed relied on a variety of measured and reconstructed data as input to a modular computer model that generates dose estimates and their uncertainties. As part of Phase 1, researchers used the reconstructed data and computer model to calculate preliminary dose estimates for populations from limited radionuclides, in a limited geographical area and time period. Phase 1 ended in FY 1990. In February 1991, the TSP decided to shift the project planning approach away from phases--which were centered around completion of major portions of technical activities--to individual fiscal years (FYs), which span October of one year through September of the next. Therefore, activities that were previously designated to occur in phases are now designated in an integrated schedule to occur in one or more of the next fiscal years into FY 1995. Task plans are updated every 6 months. In FY 1992, scientists will continue to improve Phase 1 data and models to calculate more accurate and precise dose estimates. The plan for FY 1992 has been prepared based …
Date:
October 1, 1991
Creator:
unknown
System:
The UNT Digital Library
Liquefaction of coals using ultra-fine particle, unsupported catalysts: In situ generation by rapid expansion of supercritical fluid solutions
The purpose of this program is to design and fabricate an experimental ultra-fine particle generation system; use this system to generate ultra-fine, iron compound, catalyst particles; and to access the ability of these ultra-fine catalyst particles to improve the performance of the solubilization stage of two-stage, catalytic-catalytic liquefaction processes. The effort applied to this program during this reporting period was devoted to experimental design and fabrication tasks.
Date:
September 1, 1991
Creator:
unknown
System:
The UNT Digital Library
Fundamental spectroscopic studies of carbenes and hydrocarbon radicals
This document details activities during this reporting period topics discussed are: The first spectroscopic identification of the HCCCO and DCCCO radicals; detection of new vibrationally excited states of the carbon chain radicals CCH and CCD and the three-membered carbene ring, cyclopropenylidene; determination of an accurate structure of the cumulene carbene H{sub 2}CCC; analysis the hyperfine structure in the SiC radical; and the undertaking of a systematic search for new sulfur bearing radicals.
Date:
May 1, 1992
Creator:
Thaddeus, P. & Gottlieb, C.
System:
The UNT Digital Library
Glossary: Carbon dioxide and climate
This Glossary contains definitions of selected CO{sub 2}-related terms as well as tables containing information related to CO{sub 2} and climate. Each term is defined with an emphasis on its relationship to CO{sub 2} and climate. Many of the definitions are then followed by a more detailed description of the term and its use. References to the literature from which the definitions were taken are listed at the end of the Glossary.
Date:
August 1, 1990
Creator:
unknown
System:
The UNT Digital Library
Titanium/gold process characterization
Characterization of the titanium/gold (Ti/Au) deposition process used at the Allied-Signal Inc., Albuquerque Microelectronics Operation (AMO) was performed. Tests were conducted to set up evaporation parameters, correlate titanium and gold thicknesses to sheet resistance, improve thickness uniformity, and reduce frontside contamination of deposit material on product wafers. The Ti/Au process is the final step in the production of integrated circuits (ICs) at the AMO wafer fabrication facility. 3 figs.
Date:
November 1, 1991
Creator:
Fajardo, L.S.
System:
The UNT Digital Library
Integrated dry NO sub x /SO sub 2 emissions control system
The DOE Cooperative Agreement No. DE-FC22-91PC90550 dated March 11, 1991, Public Service Company of Colorado has prepared the following quarterly report for Phases I, IIA, and IIB of the Integrated Dry NO{sub x}SO{sub 2} Emissions Control System Project. This project includes low NO{sub x} burners with NO{sub x} ports (post firing air injection), humidification and dry sorbent injection.
Date:
February 15, 1992
Creator:
unknown
System:
The UNT Digital Library
Evaluation of weldments in Type 21-6-9 stainless steel for Compact Ignition Tokamak structural applications: Phase 1
Primary design considerations for the Compact Ignition Tokamak toroidal field-coil cases are yield strength and toughness in the temperature range from 77 to 300 K. Type 21-6-9 stainless steel, also still known by its original Armco Steel Company trade name Nitronic 40, is the proposed alloy for this application. It has high yield strength and usually adequate base metal toughness, but weldments in thick sections have not been adequately characterized in terms of mechanical properties or hot-cracking propensity. In this study, weldability of the alloy in heavy sections and the mechanical properties of the resultant welds were investigated including tensile yield strength and Charpy V-notch toughness at 77 K and room temperature. Weldments were made in four different base metals using seven different filler metals. None of the weldments showed any indication of hot-cracking problems. All base metals, including weldment heat-affected zones, were found to have adequate strength and impact toughness at both test temperatures. Weld metals, on the other hand, except ERNiCr-3 and ENiCrFe-3 had impact toughnesses of less than 67 J at 77 K. Inconel 82 had an average weld metal impact toughness of over 135 J at 77 K, and although its strength at 77 K is …
Date:
June 1, 1991
Creator:
Alexander, D. J.; Goodwin, G. M. & Bloom, E. E.
System:
The UNT Digital Library
Influence of compositional modifications on the corrosion of iron aluminides of molten nitrate salts
The corrosion of iron-aluminum alloys by molten nitrate salt as a function of aluminum, chromium, and other minor elements has been studied as part of an alloy design effort aimed at the development of a strong, ductile, corrosion-resistant FeAl type of aluminide. Short- term weight change data were used to examine the compositional dependence of the corrosion processes that occurred upon exposure of iron aluminides to highly oxidizing nitrate salts of 650{degrees}C. Corrosion resistance was found to increase with increasing aluminum concentrations of the alloy up to approximately 30 at. % Al. Chromium additions to the aluminide were not detrimental and may have improved the corrosion behavior for certain aluminum concentrations. No effects of minor alloying additions (C, B, Ti, and Zr) could be determined. The best overall corrosion resistance as measured by weight change results were obtained for an Fe-35.8 at. % Al aluminide containing some chromium. Based on linear weight loss kinetics, the weight change measurements for the most resistant compositions predict corrosion rates of 300 {mu}m/year or less at 650{degrees}C. These rates are substantially better than typical nickel-based alloys and stainless steels. From a consideration of the weight changes; the microstructural, thermodynamic, and X-ray diffraction data; and …
Date:
January 1, 1991
Creator:
Tortorelli, P. F. & Bishop, P. S.
System:
The UNT Digital Library
Comparison of TRAC and RELAP5 reactor system calculations for a DEGB LOCA in K-14. 1
A comparison of TRAC and RELAP5 predictions of steady-state and DEGB LOCA results (FI phase) for K-14.1 has been made. Both codes had been previously benchmarked against 1985 L Reactor AC Flow data and were under configuration control. The purpose of the code-to-code comparison is to provide insight on the transient uncertainty in TRAC plenum and tank bottom plenum pressures. The comparisons focus on LOCA results between 0.5 and 2.0 s, which is the primary period of interest for Flow Instability (FI) limits.
Date:
September 1, 1990
Creator:
Griggs, D.P. (Westinghouse Savannah River Co., Aiken, SC (United States)) & Liebmann, M.L. (Wais and Associates (United States))
System:
The UNT Digital Library