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Texas Department of Transportation Contract Reports
114
Construction Report
84
San Antonio Monthly Reports
43
San Antonio Monthly Permit Report
42
San Antonio Board of Adjustment Monthly Report
41
Fiscal Year 1997
39
Fiscal Year 1998
32
Construction and Maintenance Report
30
Texas Register
30
Fiscal Year 1994
27
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77,328 Matching Results
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Chemical contaminants on DOE lands and selection of contaminant mixtures for subsurface science research
This report identifies individual contaminants and contaminant mixtures that have been measured in the ground at 91 waste sites at 18 US Department of Energy (DOE) facilities within the weapons complex. The inventory of chemicals and mixtures was used to identify generic chemical mixtures to be used by DOE's Subsurface Science Program in basic research on the subsurface geochemical and microbiological behavior of mixed contaminants (DOE 1990a and b). The generic mixtures contain specific radionuclides, metals, organic ligands, organic solvents, fuel hydrocarbons, and polychlorinated biphenyls (PCBs) in various binary and ternary combinations. The mixtures are representative of in-ground contaminant associations at DOE facilities that are likely to exhibit complex geochemical behavior as a result of intercontaminant reactions and/or microbiologic activity stimulated by organic substances. Use of the generic mixtures will focus research on important mixed contaminants that are likely to be long-term problems at DOE sites and that will require cleanup or remediation. The report provides information on the frequency of associations among different chemicals and compound classes at DOE waste sites that require remediation.
Date:
April 1, 1992
Creator:
Riley, R.G. & Zachara, J.M. (Pacific Northwest Lab., Richland, WA (United States))
Object Type:
Report
System:
The UNT Digital Library
Ceramic microstructures and their elucidation by imaging, diffraction and spectroscopic methods
The development and potential utilization of ceramic materials is dependent on a systematic effort involving processing, characterization and appropriate property measurements. The methods of characterization are numerous and it is important to employ the one that is appropriate to the problem both in terms of its information content and the achievable level of resolution. With the incorporation of fine probe forming capabilities in a transmission electron microscope and the development of related diffraction, imaging and spectroscopic methods, it is now possible to obtain structural and chemical information from the same region of the sample at high spatial resolution. In this review, recent advances along with representative examples in the application of high resolution electron microscopy (HREM), convergent beam electron diffraction (CBED), low atomic number element microanalysis by x-ray emission spectroscopy (XES), fine structures in electron energy-loss spectroscopy (EELS) and specific site occupancy determination by channeling experiments are discussed.
Date:
February 1, 1992
Creator:
Kirshnan, K.M.
Object Type:
Article
System:
The UNT Digital Library
(Hadamard Raman imaging)
We have used newly developed holographic notch filters for obtaining both Stokes and anti-Stokes Raman images. The filters can be used as close as {plus minus}70 cm{sup {minus}1} from the Rayleigh line. We have demonstrated that they are insensitive to polarization, have 80% transmission across their clear apertures and block laser light by 10{sup 4}. The devices now have replaced sharp-cut glass filters on our microscope. We have successfully developed multispectral control and display software for the microscope. 4 refs., 3 figs.
Date:
January 1, 1991
Creator:
unknown
Object Type:
Report
System:
The UNT Digital Library
Anion-exchange resin-based desulfurization process
Under DOE Grant No. FG22-90PC90309, the University of Tennessee Space Institute (UTSI) is contracted to further develop its anion-exchange, resin-based desulfurization concept to desulfurize alkali metal sulfates. From environmental as well as economic viewpoints, it is necessary to remove soluble sulfates from the wastes created by flue gas desulfurization systems. In order to do this economically, a low-cost desulfurization process for spent sorbents is necessary. UTSI's anion-exchange resin-based desulfurization concept is believed to satisfy these requirements.
Date:
January 1, 1992
Creator:
Sheth, A.C.; Strevel, S.D. & Dharmapurikar, R.
Object Type:
Report
System:
The UNT Digital Library
The use of synchrotron radiation for the analysis of coal combustion products
An understanding of the chemical composition of such slags under boiler operating conditions and as function of the mineral composition of various coals is the ultimate goal of this program. The experiment involves scanning through the K- or L-shell absorption edge of the element in question. The structure of the absorption edge, consisting of transitions to unoccupied molecular levels, can be compared to those of model compounds for identification. The relative position of the absorption edge can yield information regarding the oxidation state of the element. This portion is the X-ray Absorption Near Edge Structure (XANES) portion of the spectrum. The Extended X-ray Absorption Fine Structure (EXFAS) region, extending from about 60 eV above the absorption edge, represents scattering from neighboring constituents and can be used to determine the coordination number of coordination distance of a specific element from its neighboring atoms. The best source of excitation energy for these experiments is an electron storage ring emitting synchrotron radiation (SR). The National Synchrotron Light Source (NSLS) at Brookhaven National Laboratory is a 2.5 GeV storage ring and emits a continuous spectrum of x rays to an energy of about 30 keV. Beam line X-19A is dedicated to XANES and EXAFS …
Date:
May 1, 1992
Creator:
Manowitz, B. & Gordon, B.
Object Type:
Article
System:
The UNT Digital Library
Ab initio calculations on collisions of low energy electrons with polyatomic molecules
The Kohn variational method is one of simplest, and oldest, techniques for performing scattering calculations. Nevertheless, a number of formal problems, as well as practical difficulties associated with the computation of certain required matrix elements, delayed its application to electron--molecule scattering problems for many years. This paper will describe the recent theoretical and computational developments that have made the complex'' Kohn variational method a practical tool for carrying out calculations of low energy electron--molecule scattering. Recent calculations on a number of target molecules will also be summarized. 41 refs., 7 figs.
Date:
August 1, 1991
Creator:
Rescigno, T. N.
Object Type:
Article
System:
The UNT Digital Library
Variability of surface fluxes over a heterogeneous semi-arid grassland
Efforts are increasing throughout the research community to improve the predictive capabilities of general circulation models (GCMs). The US Department of Energy's Atmospheric Radiation Measurement (ARM) program has stated its goals as improving the representation and parameterization of cloud radiative forcing and feedbacks in GCMs by a combined modeling and experimental approach. Along with ambient atmospheric conditions, including advection of water vapor and cloud nuclei from other regions, cloud dynamics depend on surface fluxes of heat and water vapor. The lower boundary of the GCM modeling domain, the earth's surface, exerts a strong influence on regional dynamics of heat and water vapor, and the heterogeneity in the surface features can be responsible for generating regional mesoscale circulation patterns. Changes in the surface vegetation due to anthropogenic activity can cause substantial changes in the ratio of sensible to latent heat flux and result in climate changes that may be irreversible. A broad variety of models for representing energy fluxes are in use, from individual leaf and canopy models to mesoscale atmospheric models and GCMs. Scaling-up a model is likely to result in significant errors, since biophysical responses often have nonlinear dependence on the abiotic environment. Thus, accurate and defensible methods for …
Date:
January 1, 1991
Creator:
Barnes, F.J.; Porch, W.; Cooper, D. (Los Alamos National Lab., NM (United States)); Kunkel, K.E. (Illinois Univ., Urbana, IL (United States)); Hipps, L. & Swiatek, E. (Utah State Univ., Logan, UT (United States))
Object Type:
Article
System:
The UNT Digital Library
Capillary liquid chromatography using laser-based and mass spectrometric detection
The research performed during the past year has mainly focused on investigating and minimizing the problems listed below that limit the practical utility of these capillary electrokinetic separation techniques in chemical analysis. (1) Analyses are hindered by poor reproducibility. This is largely a result of complicated and irreproducible capillary wall-solute interactions that often result in adsorption and mobility changes. (2) While the Micellar Electrokinetic Capillary Chromatography technique permits the separations of neutral solutes, hydrophobic compounds are difficult to separate and manipulation of capacity factors is critically important due to a limited elution range. Because of the limited elution range, it is also beneficial to enhance separation selectivity through the use of non-traditional surfactants. (3) The very small solute band volumes require that on-column'' detection be performed (usually optical detection) and this seriously limits detectability. Laser fluorimetry is particularly amenable to on- column detection with these capillary separation technique. We have explored methods of on-column labeling and multi-wavelength detection to expand the utility of this mode of detection. 35 refs., 7 figs.
Date:
January 1, 1991
Creator:
Sepaniak, M.J. & Cook, K.D.
Object Type:
Report
System:
The UNT Digital Library
Evaluation of a Cray performance tool using a large hydrodynamics code
This paper will discuss one of these automatic tools that has been developed recently by Cray Research, Inc. for use on its parallel supercomputer. The tool is called ATEXPERT; when used in conjunction with the Cray Fortran compiling system, CF77, it produces a parallelized version of a code based on loop-level parallelism, plus information to enable the programmer to optimize the parallelized code and improve performance. The information obtained through the use of the tool is presented in an easy-to-read graphical format, making the digestion of such a large quantity of data relatively easy and thus, improving programmer productivity. In this paper we address the issues that we found when the took a large Los Alamos hydrodynamics code, PUEBLO, that was highly vectorizable, but not parallelized, and using ATEXPERT proceeded to parallelize it. We show that through the advice of ATEXPERT, bottlenecks in the code can be found, leading to improved performance. We also show the dependence of performance on problem size, and finally, we contrast the speedup predicted by ATEXPERT with that measured on a dedicated eight-processor Y-MP.
Date:
January 1, 1992
Creator:
Lord, K.M. (Cray Research, Inc., Eagan, MN (United States)) & Simmons, M.L. (Los Alamos National Lab., NM (United States))
Object Type:
Article
System:
The UNT Digital Library
Manufactured Homes Acquisition Program : Heat Loss Assumptions and Calculations, Heat Loss Coefficient Tables.
This manual is intended to assist builders of manufactured homes in assessing the thermal performance of structural components used in the Manufactured Housing Acquisition Program (MAP) sponsored by the Bonneville Power Administration (BPA). U-factors for these components are calculated using the ASHRAE (1989) parallel heat loss method, with adaptations made for the construction practices found in the Pacific Northwest manufactured home industry. This report is divided into two parts. The first part describes the general assumptions and calculation procedures used to develop U-factors and R-values for specific materials used in the construction industry, overall U-factors for component sections, and the impact of complex framing and thermal configurations on various components' heat loss rates. The individual components of manufactured homes are reviewed in terms of overall thermal conductivity. The second part contains tables showing the results of heat loss calculations expressed as U-factors for various configurations of the major building components: floor systems, ceiling systems, wall systems, windows, doors and skylights. These values can be used to establish compliance with the MAP specifications and thermal performance criteria or to compare manufactured homes built to different standards.
Date:
May 1, 1992
Creator:
Davis, Bob & Baylon, David
Object Type:
Report
System:
The UNT Digital Library
Analysis of energy use in building services of the industrial sector in California: A literature review and a preliminary characterization
Energy use patterns in many of California's fastest-growing industries are not typical of those in the mix of industries elsewhere in the US. Many California firms operate small and medium-sized facilities, often in buildings used simultaneously or interchangeably for commercial (office, retail, warehouse) and industrial activities. In these industrial subsectors, the energy required for building services'' to provide occupant comfort and necessities (lighting, HVAC, office equipment, computers, etc.) may be at least as important as the more familiar process energy requirements -- especially for electricity and on-peak demand. In this report, published or unpublished information on energy use for building services in the industrial sector have been compiled and analyzed. Seven different sources of information and data relevant to California have been identified. Most of these are studies and/or projects sponsored by the Department of Energy, the California Energy Commission, and local utilities. The objectives of these studies were diverse: most focused on industrial energy use in general, and, in one case, the objective was to analyze energy use in commercial buildings. Only one of these studies focused directly on non-process energy use in industrial buildings. Our analysis of Northern California data for five selected industries shows that the contribution …
Date:
April 1, 1991
Creator:
Akbari, H.; Borgers, T.; Gadgil, A. & Sezgen, O.
Object Type:
Report
System:
The UNT Digital Library
Humic substance formation during wastewater infiltration
Soil infiltration of wastewater effluents is a widely practiced method of treatment and disposal/reuse throughout the world. Renovation of the wastewater results from a wide variety of complex physicochemical and biological processes. One set of processes is speculated to involve the accumulation of organic matter by filtration and sorption followed by formation of humic substances. This humic substance formation can effect the performance of soil treatment systems by contributing to soil pore clogging and reduction in hydraulic capacity, and by yielding reactive substances and an enhancement of purification processes. While there has been a wealth of research into the nature and genesis of humic substances in terrestrial environments, there has been limited research of humic substance formation during soil infiltration of wastewater. The purpose of the research reported herein was to determine if humic substances can form under conditions typical of those present during wastewater infiltration into natural soil systems. This work was conducted during 1989 to 1990 as a collaborative effort between the Centre for Soil and Environmental Research, located in Aas, Norway and the Institute for Water, Soil and Air Hygiene located in Langen, West Germany. 11 refs., 3 figs., 6 tabs.
Date:
January 1, 1991
Creator:
Siegrist, R.L. (Oak Ridge National Lab., TN (United States)); Hildmann-Smed, R.; Filip, Z.K. (Bundesgesundheitsamt (BGA), Langen (Germany). Inst. fuer Wasser-, Boden- und Lufthygiene) & Jenssen, P.D. (Norges Landbrukshoegskole, Aas (Norway). Centre for Soil and Environmental Research)
Object Type:
Article
System:
The UNT Digital Library
Cationically polymerizable monomers derived from renewable sources
The objective of this project is to make use of products obtained from renewable plant sources as monomers for the direct production of polymers which can be used for a wide range of plastic applications. In this report is described progress in the synthesis and polymerization of cationically polymerizable monomers and oligomers derived from botanical oils, terpenes, natural rubber, and lignin. Nine different botanical oils were obtained from various sources, characterized and then epoxidized. Their photopolymerization was carried out using cationic photoinitiators and the mechanical properties of the resulting polymers characterized. Preliminary biodegradation studies are being conducted on the photopolymerized films from several of these oils. Limonene was cationically polymerized to give dimers and the dimers epoxidized to yield highly reactive monomers suitable for coatings, inks and adhesives. The direct phase transfer epoxidation of squalene and natural rubber was carried out. The modified rubbers undergo facile photocrosslinking in the presence of onium salts to give crosslinked elastomers. 12 refs., 3 figs., 10 tabs.
Date:
October 1, 1991
Creator:
Crivello, J. V.
Object Type:
Report
System:
The UNT Digital Library
Ceramic technology for Advanced Heat Engines Project
Significant accomplishments in fabricating ceramic components for advanced heat engine programs have provided evidence that the operation of ceramic parts in high-temperature engine environments is feasible. However, these programs have also demonstrated that additional research is needed in materials and processing development, design methodology, and database and life prediction before industry will have a sufficient technology base from which to produce reliable cost-effective ceramic engine components commercially. An assessment of needs was completed, and a five year project plan was developed with extensive input from private industry. The project approach includes determining the mechanisms controlling reliability, improving processes for fabricating existing ceramics, developing new materials with increased reliability, and testing these materials in simulated engine environments to confirm reliability. Although this is a generic materials project, the focus is on the structural ceramics for advanced gas turbine and diesel engines, ceramic bearings and attachments, and ceramic coatings for thermal barrier and wear applications in these engines. To facilitate the rapid transfer of this technology to US industry, the major portion of the work is being done in the ceramic industry, with technological support from government laboratories, other industrial laboratories, and universities. This project is managed by ORNL for the Office …
Date:
July 1, 1991
Creator:
Johnson, D. R.
Object Type:
Report
System:
The UNT Digital Library
(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
Object Type:
Report
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.
Object Type:
Report
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.
Object Type:
Report
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.
Object Type:
Report
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.
Object Type:
Report
System:
The UNT Digital Library
Particle production and spectra in E802 at BNL-AGS
The production of {pi}, K, and protons measured in the E802 spectrometer are studied for p+A and Si+A collisions. Systematic properties of particle spectra and rapidity density distributions are discussed in terms of centrality and reaction system. A detailed comparison of the data to the RQMD model, which employs the experimental acceptance and cuts are presented. 8 refs., 6 figs.
Date:
January 1, 1991
Creator:
Videbaek, F.
Object Type:
Article
System:
The UNT Digital Library
An update on environmental, health and safety issues of interest to the photovoltaic industry
There is growing interest in the environmental, health, and safety issues related to new photovoltaic technologies as they approach commercialization. Such issues include potential toxicity of II--VI compounds; the impacts of new environmental regulations on module manufacturers; and, the need for recycling of spent modules and manufacturing wastes. This paper will review these topics. 20 refs.
Date:
January 1, 1992
Creator:
Moskowitz, P. D.; Viren, J. & Fthenakis, V. M.
Object Type:
Article
System:
The UNT Digital Library
X-ray, soft x-ray, and vuv beam position monitor
An x-ray beam position monitor has been developed and is currently operational at the NIST beamline X-24A of the National Synchrotron Light Source, Upton, NY. It was developed to accurately measure the vertical position of the synchrotron beam and to allow precise positioning of beamline optics. It is an area type monitor positioned 5.6 meters from the Tangent Point and precedes all beamline instrumentation. Vertical beam position is given by the differential photoemission current from two grids mounted on a Macor frame. The monitor also senses the total photon beam flux. 7 refs., 4 figs.
Date:
January 1, 1991
Creator:
Karlin, B.A. (Brookhaven National Lab., Upton, NY (United States)); Cowan, P.L. (Argonne National Lab., IL (United States)) & Woicik, J.C. (National Inst. of Standards and Technology (IMSE), Gaithersburg, MD (United States))
Object Type:
Article
System:
The UNT Digital Library
A design of experiment study of plasma sprayed alumina-titania coatings
An experimental study of the plasma spraying of alumina-titania powder is presented in this paper. This powder system is being used to fabricate heater tubes that emulate nuclear fuel tubes for use in thermal-hydraulic testing. Coating experiments were conducted using a Taguchi fractional-factorial design parametric study. Operating parameters were varied around the typical spray parameters in a systematic design of experiments in order to display the range of plasma processing conditions and their effect on the resultant coating. The coatings were characterized by hardness and electrical tests, image analysis, and optical metallography. Coating qualities are discussed with respect to dielectric strength, hardness, porosity, surface roughness, deposition efficiency, and microstructure. The attributes of the coatings are correlated with the changes in operating parameters.
Date:
January 1, 1992
Creator:
Steeper, T. J. (Du Pont de Nemours (E.I.) and Co., Aiken, SC (United States). Savannah River Lab.); Varacalle, D. J. Jr.; Wilson, G. C. (EG and G Idaho, Inc., Idaho Falls, ID (United States)); Riggs, W. L. II (Tubal Cain Co., Loveland, OH (United States)); Rotolico, A. J. & Nerz, J. E. (Metco/Perkin-Elmer, Westbury, NY (United States))
Object Type:
Article
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
Object Type:
Report
System:
The UNT Digital Library