Monthly report providing tabular statistical information about motor vehicle accidents in rural areas of Texas during 1992, with data broken out by various criteria including number of persons, locations, types of accidents, time of day, and other factors.

Monthly report providing tabular statistical information about motor vehicle accidents in Texas during 1992, with data broken out by various criteria including number of persons, locations, types of accidents, time of day, and other factors.

The purpose if this study was to better define the range of saturated horizontal hydraulic conductivities in the 100-N Area of the Hanford Site in southeastern Washington for use in a numerical groundwater model. Three methods were used for determining aquifer properties and are discussed within this report (1) reanalysis of past pumping test data using a pressure derivative method to identify the data in the radial flow regime for analysis by traditional graphical techniques, (2) sinusoidal analysis techniques described in Ferris that utilize water-table responses to river-level variations, and (3) the basic flow equation for groundwater.

The purpose if this study was to better define the range of saturated horizontal hydraulic conductivities in the 100-N Area of the Hanford Site in southeastern Washington for use in a numerical groundwater model. Three methods were used for determining aquifer properties and are discussed within this report (1) reanalysis of past pumping test data using a pressure derivative method to identify the data in the radial flow regime for analysis by traditional graphical techniques, (2) sinusoidal analysis techniques described in Ferris that utilize water-table responses to river-level variations, and (3) the basic flow equation for groundwater.

The main purpose of this project is to produce a feedstock from preparation plant fines from an Illinois coal that is ideal for a slurry fed, slagging, entrained-flow coal gasifier. The high sulfur content and high Btu value of Illinois coals are particularly advantageous in such a gasifier; preliminary calculations indicate that the increased cost of removing sulfur from the gas from a high sulfur coal is more than offset by the increased revenue from the sale of the elemental sulfur; additionally the high Btu Illinois coal concentrates more energy into the slurry of a given coal to water ratio. The Btu is higher not only because of the higher Btu value of the coal but also because Illinois coal requires less water to produce a pumpable slurry than western coal, i.e., as little as 30--35% water may be used for Illinois coal as compared to approximately 45% for most western coals. Destec Energy, a wholly-owned subsidiary of Dow Chemical Company, will provide guidelines and test compatibility of the slurries developed for gasification feedstock. Williams Technologies, Inc., will provide their expertise in long distance slurry pumping, and test selected products for viscosity, pumpability, and handleability. The Illinois State Geological Survey …

Infrared reflectance between 4000 and 100 cm{sup {minus}1} and optical spectra between 1.8 and 6.2 eV of high purity silica implanted with nominal doses of 1, 3 and 6 {times} 10{sup 16} Pb ions/cm{sup 2} were recorded before and after annealing at 400, 600, and 800C for 1 hour. Curve resolution analysis of the Si-O stretching region resulted in six peaks which were characterized by their lineshape parameters. The oscillator strength of the ion induced defect peak at 1035 cm{sup {minus}1} was found to depend on ion dose. The defect band at 1035 cm{sup {minus}1} decreased to an intensity comparable to that of the unimplanted glass after thermal annealing for 1 hour at 800C. Far infrared spectra indicated the formation of lead silicate particles after annealing.

FLOWTRAN-TF is a new two-component, two-phase thermal-hydraulics code to capture the detailed assembly behavior associated with loss-of-coolant accident analyses in multichannel assemblies of the SRS reactors. The local interfacial area of the two-phase mixture is computed by summing the interfacial areas contributed by each of three flow regimes. For smooth flow regime transitions, the code uses an interpolation technique in terms of component void fraction for each basic flow regime.

The main purpose of this project was to produce a feedstock from preparation plant fines from an Illinois (IL) coal that is ideal for a slurry fed, slagging, entrained-flow coal gasifier. The high-sulfur content and high-Btu value of IL coals are Particularly advantageous in such a gasifier; preliminary-calculations indicate that the increased cost of removing sulfur from the gas from a high-sulfur coal is more than offset b the increased revenue from the sale of the elemental sulfur; additionally the high-Btu IL coal concentrates more energy into the slurry of a given coal to water ratio. The Btu is--higher not only because of the hither Btu value of the coal but also because IL coal requires less water to produce a pumpable slurry than western coal, i.e., as little as 30--35% water may be used for IL coal as compared to approximately 45% for most western coals. During the contract extension, additional coal testing was completed confirming the fact that coal concentrates can be made from plant waste under a variety of flotation conditions 33 tests were conducted, yielding an average of 13326 Btu with 9.6% ash while recovering 86.0%-Of the energy value.

Growth assays reveal that Rhodococcus rhodochrous IGTS8 can utilize a wide range of organosulfur compounds as the sole source of sulfur. Compounds that are utilized include thiophenes, sulfides, disulfides, mercaptans, sulfoxides, and sulfones. None of the organosulfur compounds tested can serve as a carbon source. A convenient spectrophotometric assay (Gibbs assay) based on the chromogenic reaction of 2,6-dichloroquinone-4-chloroimide with aromatic hydroxyl groups was developed and used in conjunction with GC/MS analysis to examine the kinetics of carbon-sulfur bond cleavage by axenic and mixed cell cultures of Rhodococcus rhodochrous IGTS8. The desulfurization trait is expressed at uniform levels during the mid-exponential phase, reaches a maximum during idiophase, and then declines in stationary-phase cells. Desulfurization rates for dibenzothiophene (DBT) range from 8 to 15 {mu}M of DBT/10{sup 12} cells/hour. Mixtures of genetically marked Rhodococcus rhodochrous IGTS8 and an organisms incapable of cleaning carbon-sulfur bonds in relevant test compounds, Enterobacter cloacae, were prepared in ratios that varied over six orders of magnitude. Growth studies revealed that Enterobacter cloacae was able to gain access to sulfur liberated from organosulfur compounds by IGTS8; however, cell-to-cell contact was required. These data also indicate that the desulfurization activity of IGTS8 cells in mixed cultures may be as …

During the second year of this project, chemical treatments examined included ammonia vapor, 0.1N NaOH, isopropanol, isopropanol plus 0.1N NaOH, methanol, and methanol plus 0.1N NaOH. The exposure of IBC-107 coal to chemical solutions was varied from minutes to days, at temperatures of 70{degrees} to 240{degrees}F, and at pressures of 800 or 1200 psi with an explosive release of pressure. Ammonia vapor was found to be the most effective chemical comminution agent; however, in tests involving combined chemical and physical treatments 240{degrees}F and 1200 psi yielded the greatest comminution with very little effect attributable to the nature of the chemical solutions. In contrast to the mere physical grinding of coal, coal samples subjected to chemical or chemical plus physical comminution can be successfully biodesulfurized by pre-grown biocatalysts. Coal samples treated with ammonia vapor yielded preferred samples for subsequent biodesulfurization. The removal of about 20% of organic sulfur from solid coal samples was observed using 24 hour treatment times. The accessibility of microorganisms to coal was shown to be the chief factor limiting the removal of organic sulfur from coal. Chemical and/or physical treatments that increase the porosity of coal were shown to increase the treatability of coal using biodesulfurization. The …

IGT has developed a microbial culture of Rhodococcus rhodochrous, designated as IGTS8, that is capable of specifically cleaving carbon-sulfur bonds in a range of organosulfur model compounds and is capable of removing organic sulfur from coal and petroleum without significantly sacrificing the calorific value of the fuel. Although IGTS8 possesses the ability to specifically remove organic sulfur from coal, a major research need is to develop improved strains of microorganisms that possess higher levels of desulfurization activity and therefore will permit more favorable biodesulfurization process conditions: faster rates, more complete removal, and smaller reactor size. Strain improvement is the single most important aspect to the development of a practical coal biodesulfurization process and accordingly is the focus of research in this project. The first steps in obtaining high levels of expression of desulfurization genes are to identify specific DNA fragments that encode desulfurization genes and to identify a DNA fragment that encodes a promoter/regulatory element that is capable of functioning at high levels in Rhodococcus rhodochrous. Both of these goals have been accomplished during the first year of this two-year research program.

The production of this Economic Evaluation Guide is one activity of AVFCAP. The guide is intended for use by project managers and fleet operators in the public sector. Public fleets have been identified as one of the most likely areas where ATFs will first gain widespread use, because of existing and impending state and federal legislative mandates, as well as for practical reasons such as centralized servicing and refueling. The purpose of this guide is to provide balanced decision-support information to project managers who are considering conducting, or currently managing, ATF demonstration programs. Information for this guide was gathered as part of a related AVFCAP activity, the development of an Information Resource Database. Economic issues related to the development and implementation of ATF programs at the local government level are extremely complex, and require an analysis of federal policies and national and international economics that is generally beyond the scope of local government project managers. The intent of this guide is to examine the information available on the economic evaluation of ATFs, and identify key elements that will help local governments realistically assess the potential costs and savings of an ATF program. The guide also discusses how these various economic …

This paper presents the design and characterization of an 8channel preamplifier-shaper intended for use with silicon strip detectors ranging in capacitance from 1 to 20pF. The nominal peaking time of the circuit is 200ns with an adjustment range of {plus_minus}50ns. The circuit has a pitch (width) of 84{mu}channel with a power dissipation of 1.2mW/channel and has been fabricated in 2{mu}m p-well CMOS. The 0pF noise is 330e with a noise slope of 64e/pF. The design approach is presented as well as both test bench and strip detector measurements.

CTH is a family of codes developed at Sandia National Laboratories for modeling complex multi-dimensional, multi-material problems that are characterized by large deformations and/or strong shocks. A two-step, second-order accurate Eulerian solution algorithm is used to solve the mass, momentum, and energy conservation equations. CTH includes models for material strength, fracture, porous materials, and high explosive detonation and initiation. Viscoplastic or rate-dependent models of material strength have been added recently. The formulations of Johnson-Cook, Zerilli-Armstrong, and Steinberg-Guinan-Lund are standard options within CTH. These models rely on using an internal state variable to account for the history dependence of material response. The implementation of internal state variable models will be discussed and several sample calculations will be presented. Comparison with experimental data will be made among the various material strength models. The advancements made in modelling material response have significantly improved the ability of CTH to model complex large-deformation, plastic-flow dominated phenomena. Detonation of energetic material under shock loading conditions has been of great interest. A recently developed model of reactive burn for high explosives (HE) has been added to CTH. This model along with newly developed tabular equations-of-state for the HE reaction by-products has been compared to one- and two-dimensional …

A series of numerical simulations have been performed using CTH to predict secondary debris formation and rear structure damage for typical bumper shields under a variety of impact geometries The simulations span a range of velocities from {approximately}3 to 12 km/s and are compared to the experiment data for the lower velocities (3 to 7 km/s). For one velocity ({approximately}7 km/s), CTH was used to demonstrate the effects of bumper thickness on secondary debris formation and rear structure damage. CTH was also used to stimulate a 12 km/s impact of a sphere on a simple Whipple bumper shield and this result will be compared to analytic damage predictions at that velocity. It has been found that CTH accurately predicts secondary debris propagation and rear damage for velocities throughout the experimentally accessible range. The CTH damage predictions at 12 km/s result in a higher ballistic limit than would be predicted from the analytic techniques.

Our goals of this research are to define the substrate oxidation pathways, the electron transport mechanisms, and the modes of energy conservation employed during the dissimilatory oxidation of sulfur by thiobacilli. We have purified APS reductase to electrophoratic homogeneity from cell-free extracts of Thiobacillus denitrificans. Sufficient protein is available to initiate the production of polyclonal antibodies and to perform the kinetic experiments.

This report describes experimental progress in characterizing and identifying redox proteins in a number of iron-oxidizing bacteria. Sections of the paper are entitled (1) In Situ electrolysis was explored to achieve enhanced yields of iron-oxidizing bacteria, (2)Structure/function studies were performed on redox-active biomolecules from Thiobacillus ferrooxidans, (3) Novel redox-active biomolecules were demonstrated in other iron autotrophs, and (4) New probes of metalloprotein electron-transfer reactions were synthesized and characterized.

Databases of mechanical properties for both the piping and reactor vessels at the Savannah River Site (SRS) were developed from weldment components (base, weld, and weld heat-affected-zone (HAZ)) of archival piping specimens in the unirradiated and irradiated conditions. Tensile, Charpy V-notch (CVN), and Compact Tension C(T) specimens were tested at 25 and 125C before and after irradiation at low temperatures (90 to 150C) to levels of 0.065 to 2.1 dpa. irradiation hardened the weldment components and reduced the absorbed energy and toughness properties from the unirradiated values. A marked difference in the Charpy V-notch absorbed energy and the elastic-plastic fracture toughness (J{sub IC}) was observed for both the base and HAZ components with the C-L orientation being lower in toughness than the L-C orientation in both the unirradiated and irradiated conditions. Fracture surface examination of the base and HAZ components of unirradiated C(T) specimens showed a ``channel`` morphology in the fracture surfaces of the C-L specimens, whereas equiaxed ductile rupture occurred in the L-C specimens. Chromium carbide precipitation in the HAZ component reduced the fracture toughness of the C-L and L-C specimens compared to the respective base component C-L and L-C specimens. Optical metallography of the piping materials showed stringers …

Assessing the mechanisms which govern the distribution, fate, and pathways of entry into biological systems, as well as the ultimate hazards associated with the radon progeny and their secondary reaction products, depends on knowledge of their chemistry. Our studies are directed toward developing fundamental information which will provide a basis for modeling studies that are requisite in obtaining a complete picture of growth, attachment to aerosols, and transport to the bioreceptor and ultimate incorporation within. Our program is divided into three major areas of research. These include measurement of the determination of their mobilities, study of the role of radon progeny ions in affecting reactions, including study of the influence of the degree of solvation (clustering), and examination of the important secondary reaction products, with particular attention to processes leading to chemical conversion of either the core ions or the ligands as a function of the degree of clustering.

Chemical reactions that proceed following either a photophysical or ionizing event, are directly influenced by the mechanisms of energy transfer and dissipation away from the primary site of absorption. Neighboring solvent or solute molecules can affect this by collisional deactivation (removal of energy), through effects in which dissociating molecules are kept in relatively close proximity for comparatively long periods of time due to the presence of the solvent, and in other ways where the solvent influences the energetics of the reaction coordinate. Research on clusters offers one of the most viable ways of elucidating the molecular details of these processes. The current program is comprised of three general areas of research. Investigation of the dynamics of ionization and the mechanisms of the early-time reactions following the interaction of ionizing electromagnetic radiation with matter; measurement of the kinetics of ensuing ion reactions with effort focused on the influence of solvation effects and identifying similarities and differences between gas and condensed phase reactions; and determination of the structure of solvated reaction centers via spectroscopy, dynamics and thermochemistry.

TVA is proposing to develop and commercially demonstrate the coproduction of electricity and fertilizer (urea) using integrated gasification/combined cycle (IGCC) technology. The coal-based coproduction demonstration project will show that the coproduction process can economically and environmentally enhance the production of both electric power and urea. As conceptualized, the proposed coproduction demonstration project facility would be designed for a nominal electrical capacity of about 250 megawatts (MW), Table I. During normal operation, the facility would produce about 150 MW of base-load electrical power and 1,000 tons per day of urea. Sulfur from the coal would be recovered as elemental sulfur. During peak power demand, the fertilizer capacity could be reduced or bypassed and the full 250 MW could be made available. This scheme would allow continuous operation of the gasifier at 100% of its rated capacity which would reduce the annual revenue requirements for power generation by permitting the production of fertilizer. As TVA`s vision of this proposal matures (i.e., as consideration is given to alternative schemes, as TVA reviews its power demands, and as more detailed engineering estimates are developed), the nature and scope of cyclic-operation may be altered.

The objectives of this report are three-fold: (1) assess physical, chemical, and biological conditions in the major embayments of Chickamauga Reservoir; (2) compare water quality and biological conditions of embayments with main river locations; and (3) identify any water quality concerns in the study embayments that may warrant further investigation and/or management actions. Embayments are important areas of reservoirs to be considered when assessments are made to support water quality management plans. In general, embayments, because of their smaller size (water surface areas usually less than 1000 acres), shallower morphometry (average depth usually less than 10 feet), and longer detention times (frequently a month or more), exhibit more extreme responses to pollutant loadings and changes in land use than the main river region of the reservoir. Consequently, embayments are often at greater risk of water quality impairments (e.g. nutrient enrichment, filling and siltation, excessive growths of aquatic plants, algal blooms, low dissolved oxygen concentrations, bacteriological contamination, etc.). Much of the secondary beneficial use of reservoirs occurs in embayments (viz. marinas, recreation areas, parks and beaches, residential development, etc.). Typically embayments comprise less than 20 percent of the surface area of a reservoir, but they often receive 50 percent or more …