Resource Type
Collection
Office of Scientific & Technical Information Technical Reports
4,957
Congressional Research Service Reports
169
Texas State Publications
144
Government Accountability Office Reports
67
Office of Technology Assessment
27
Technical Report Archive and Image Library
20
Texas State Auditor's Office: Reports
17
End of Term Publications
4
Serial/Series Title
Texas Motor Vehicle Traffic Accident Summaries
81
Argonne National Laboratory Reports
17
Summary of All Reported Accidents in Rural Areas of Texas
14
Summary of All Reported Accidents in the State of Texas
14
Texas Department of Transportation Contract Reports
10
Texas Real Estate Center Trends
9
Fiscal Year 2000
8
San Antonio Board of Adjustment Monthly Report
8
San Antonio Monthly Reports
8
Construction Report
7
78 More
Country
Decade
Month
Language
5,405 Matching Results
Results open in a new window/tab.
Results:
1 - 24 of
5,405
next
Inexpensive cross-flow hydropower turbine at Arbuckle Mountain Hydroelectric Project
This report documents the first three and half years of operation and maintenance on the Arbuckle Mountain Hydroelectric Project. Located on a flashy mountain stream in northern California, the project was designed, built and tested through a Cooperative Agreement between the US DOE and OTT Engineering, Inc. (OTT). The purpose of the Agreement is to build and intensively test an inexpensive American-made cross-flow turbine and to provide information to the DOE on the cost, efficiency, operation, and maintenance of the unit. It requires that OTT document for DOE a summary of the complete operating statistics, operation and maintenance cost, and revenues from power sales for a two-year operating period. Several unique events occurred between the initial start-up (December 1986) and the beginning of the 1989 generation season (October 1988) that delayed the first year's full operation and provided unique information for a demonstration project of this type. Accordingly, this report will discuss certain major problems experienced with the design, operation and maintenance, and energy production, as well as the operation and maintenance costs and value of the power produced for the first three and half years of operation. 9 figs., 2 tabs.
Date:
July 1, 1991
Creator:
unknown
System:
The UNT Digital Library
Study of ICRF wave propagation and plasma coupling efficiency in a linear magnetic mirror device
Ion Cyclotron Range of Frequency (ICRF) wave propagation in an inhomogeneous axial magnetic field in a cylindrical plasma-vacuum system has historically been inadequately modelled. Previous works either sacrifice the cylindrical geometry in favor of a simpler slab geometry, concentrate on the resonance region, use a single mode to represent the entire field structure, or examine only radial propagation. This thesis performs both analytical and computational studies to model the ICRF wave-plasma coupling and propagation problem. Experimental analysis is also conducted to compare experimental results with theoretical predictions. Both theoretical as well as experimental analysis are undertaken as part of the thesis. The theoretical studies simulate the propagation of ICRF waves in an axially inhomogeneous magnetic field and in cylindrical geometry. Two theoretical analysis are undertaken - an analytical study and a computational study. The analytical study treats the inhomogeneous magnetic field by transforming the (r,z) coordinate into another coordinate system ({rho},{xi}) that allows the solution of the fields with much simpler boundaries. The plasma fields are then Fourier transformed into two coupled convolution-integral equations which are then differenced and solved for both the perpendicular mode number {alpha} as well as the complete EM fields. The computational study involves a multiple …
Date:
July 1, 1991
Creator:
Peng, S.Y.
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.
System:
The UNT Digital Library
Studies of Plasma Transport
This report discusses the charge-coupled device camera and other plasma diagnostic equipment used to measure plasma density and other plasma properties. (LSP)
Date:
July 22, 1991
Creator:
Malmberg, J. H.; O'Neil, T. M. & Driscoll, C. F.
System:
The UNT Digital Library
Geophysics: Building E5032 decommissioning, Aberdeen Proving Ground
integration of data from surveys using three geophysical technologies has provided information used to define the locations of buried utilities, tanks, vaults, and debris near building E5032 at the Aberdeen Proving Ground. Ground penetrating radar (GPR) profiles indicate the presence of buried pipes, tanks, reinforcement rods (rebar), and remnants of railroad tracks. A magnetic map constructed from a detailed magnetic survey on the north side of the building outlines buried iron-rich objects that are interpreted to be iron pipes, tank, and other debris of uncertain origin at relatively shallow depths. Horizontal electrical resistivity surveys and vertical electrical resistivity soundings essentially corroborated the findings obtained with the magnetometer and GPR. In addition, a highly resistance layer was observed on the east side of the building where a former railroad bed with a thick grave fill is believed to immediately underlie the lawn. The resistivity data show no evidence of a conductive leachate plume. Geophysical measurements from three techniques over a buried concrete slab approximately 130 ft north of Building E5032 give geophysical signatures interpreted to be due to the presence of a large iron tank or vault. An attempt was made to gather meaningful magnetic data on the east, west, and …
Date:
July 1, 1991
Creator:
McGinnis, L.D. & Miller, S.F.
System:
The UNT Digital Library
Acceleration of electrons using an inverse free electron laser auto- accelerator
We present data from our study of a device known as the inverse free electron laser. First, numerical simulations were performed to optimize the design parameters for an experiment that accelerates electrons in the presence of an undulator by stimulated absorption of radiation. The Columbia free electron laser (FEL) was configured as an auto-accelerator (IFELA) system; high power (MW's) FEL radiation at {approximately}1.65 mm is developed along the first section of an undulator inside a quasi-optical resonator. The electron beam then traverses a second section of undulator where a fraction of the electrons is accelerated by stimulated absorption of the 1.65 mm wavelength power developed in the first undulator section. The second undulator section has very low gain and does not generate power on its own. We have found that as much as 60% of the power generated in the first section can be absorbed in the second section, providing that the initial electron energy is chosen correctly with respect to the parameters chosen for the first and second undulators. An electron momentum spectrometer is used to monitor the distribution of electron energies as the electrons exit the IFELA. We have found; using our experimental parameters, that roughly 10% of …
Date:
July 1, 1992
Creator:
Wernick, I.K. & Marshall, T.C.
System:
The UNT Digital Library
Savannah River Site computing architecture migration guide
The SRS Computing Architecture is a vision statement for site computing which enumerates the strategies which will guide SRS computing efforts for the 1990s. Each strategy is supported by a number of feature statements which clarify the strategy by providing additional detail. Since it is a strategic planning document, the Architecture has sitewide applicability and endorsement but does not attempt to specify implementation details. It does, however, specify that a document will be developed to guide the migration from the current site environment to that envisioned by the new architecture. The goal of this document, the SRS Computing Architecture Migration Guide, is to identify specific strategic and tactical tasks which would have to be completed to fully implement the architectural vision for site computing as well as a recommended sequence and timeframe for addressing these tasks. It takes into account the expected availability of technology, the existing installed base, and interdependencies among architectural components and objectives.
Date:
July 30, 1991
Creator:
unknown
System:
The UNT Digital Library
Two-dimensional nuclear magnetic resonance studies of molecular structure in liquids and liquid crystals
Magnetic couplings between protons, such as through-space dipole couplings, and scalar J-couplings depend sensitively on the structure of the molecule. Two dimensional nuclear magnetic resonance experiments provide a powerful tool for measuring these couplings, correlating them to specific pairs of protons within the molecule, and calculating the structure. This work discusses the development of NMR methods for examining two such classes of problems -- determination of the secondary structure of flexible molecules in anisotropic solutions, and primary structure of large biomolecules in aqueous solutions. 201 refs., 84 figs., 19 tabs.
Date:
July 1, 1991
Creator:
Rucker, S.P.
System:
The UNT Digital Library
Nonlinear spectroscopic studies of interfacial molecular ordering
The second order nonlinear optical processes of second harmonic generation and sum frequency generation are powerful new probes of surfaces. They possess unusual surface sensitivity due to the symmetry properties of the nonlinear susceptibility. In particular, infrared-visible sum frequency generation (SFG) can obtain the vibrational spectrum of sub-monolayer coverages of molecules. In this thesis, we explore the unique information that can be obtained from SFG. We take advantage of the sensitivity of SFG to the conformation of alkane chains to study the interaction between adsorbed liquid crystal molecules and surfactant treated surfaces. The sign of the SFG susceptibility depends on the sign of the molecular polarizability and the orientation, up or down, of the molecule. We experimentally determine the sign of the susceptibility and use it to determine the absolute orientation to obtain the sign of the molecular polarizability and show that this quantity contains important information about the dynamics of molecular charge distributions. Finally, we study the vibrational spectra and the molecular orientation at the pure liquid/vapor interface of methanol and water and present the most detailed evidence yet obtained for the structure of the pure water surface. 32 refs., 4 figs., 2 tabs.
Date:
July 1, 1991
Creator:
Superfine, R.
System:
The UNT Digital Library
CGVIEW: A program to generate isometric and perspective views of combinatorial geometries
The prototype of a graphical debugger for combinatorial geometry (CG) is described. The prototype debugger consists of two parts: a FORTRAN-based view'' generator and a Microsoft Windows application for displaying the geometry. This document describes the code CGVIEW, which comprises the first part of the system. User-specified options permit the selection of an arbitrary viewpoint in space and the generation of either an isometric or perspective view. Additionally, any combination of zones, materials, or regions can be flagged as invisible to facilitate the inspection of internal details of the geometry. In the same manner, an arbitrary body can be cut away from the geometry to facilitate inspection and debugging. Examples illustrating the various options are described.
Date:
July 1, 1992
Creator:
Burns, T.J.
System:
The UNT Digital Library
Establishment and maintenance of a coal sample bank and data base
In this Project Status Report for 7/9/89--10/8/89, results of a comparative study of coal sample deterioration in several container types were presented. In April 1990, one year after the initial analyses, the set of analyses was repeated on the most important container types. The new results are included in Table 2. During the current reporting period a total of 42 data printouts were distributed. In addition, 7 special data requests were fulfilled by either search/sort and printout or creation of a data disk, resulting in distribution of limited information on 2083 samples. Several preliminary requests for Sample Bank and Data Base information and price quotations have also been handled.
Date:
July 11, 1990
Creator:
Davis, A.
System:
The UNT Digital Library
Beam and viewing dump positioning inside TFTR for CTS alpha-particle diagnostics
A collective Thomson scattering (CTS) diagnostic system for localized measurement of energetic ions is being developed for TFTR. This system will use a 200KW, 56GHz gyrotron and a sensitive heterodyne receiver. In addition, a key element of this system will be beam and viewing dumps which are needed to minimize detection of stray gyrotron and ECE background radiation by the receiver system. It is the purpose of this study to determine the size and location of these dumps inside TFTR taking into account beam refraction and launch and receiver antenna optics scanning. The beam dump must cover all the area in the vacuum chamber where the beam is expected to impinge, and the viewing dump must cover all the areas within the direct line of sight of the receiver antenna. The beam launch system and the receiver antenna are to be placed nearly symmetrically above and below the midplane of the tokamak vacuum vessel, respectively. The beam dump is to be placed at the bottom inside of the vacuum vessel to absorb the gyrotron beam which will be launched from a top port. The viewing dump is expected to be placed symmetrically at the top inside of the vacuum vessel, …
Date:
July 15, 1991
Creator:
Rhee, D.Y.; Woskov, P.P. (Massachusetts Inst. of Tech., Cambridge, MA (United States). Plasma Fusion Center); Ellis, R. & Park, H. (Princeton Univ., NJ (United States). Plasma Physics Lab.)
System:
The UNT Digital Library
Po-210 as long-term integrating radon indicator in the indoor environment
The general objective is to improve the knowledge about the transferring processes leading from airborne radon/radon daughters to embedded Po-210 in hard surfaces in the indoor environment. The specific goal of the research is to identify situations in which the surface activity of Po-210 can be used as a long-term indicator of lung cancer risk from past or future radon exposures.
Date:
July 1, 1990
Creator:
Samuelsson, C.
System:
The UNT Digital Library
Advanced Coal Conversion Process Demonstration (Project)
This report contains a description of technical progress made on the Advanced Coal Conversion Process Demonstration Project (ACCP). The project is a US Department of Energy Innovative Clean Coal Technology Project. The cooperative agreement defining the project is between DOE and the Rosebud SynCoal Partnership RSCP. The RSCP is a partnership between Western Energy Company (WECo), a subsidiary of Entech, Montana Power's non-utility group, and NRG, a subsidiary of Northern States Power. The ACCP is a method of upgrading low ranked coals by reducing the moisture and sulfur content and increasing the heating value. The facility is being constructed at WECo's Rosebud No. 6 coal mine, west of Colstrip, Montana. This report contains both a history of the process development and a report of technical progress made since the beginning of the Clean Coal 1 cooperative agreement.
Date:
July 1, 1991
Creator:
unknown
System:
The UNT Digital Library
Analysis of natural gas supply strategies at Fort Drum
This analysis investigates strategies for Fort Drum to acquire a reliable natural gas supply while reducing its gas supply costs. The purpose of this study is to recommend an optimal supply mix based on the life-cycle costs of each strategy analyzed. In particular, this study is intended to provide initial guidance as to whether or not the building and operating of a propane-air mixing station is a feasible alternative to the current gas acquisition strategy. The analysis proceeded by defining the components of supply (gas purchase, gas transport, supplemental fuel supply); identifying alternative options for each supply component; constructing gas supply strategies from different combinations of the options available for each supply component and calculating the life-cycle costs of each supply strategy under a set of different scenarios reflecting the uncertainty of future events.
Date:
July 1, 1992
Creator:
Stucky, D. J.; Shankle, S. A. & Anderson, D. M.
System:
The UNT Digital Library
Excitation of high-n toroidicity-induced shear Alfven eigenmodes by energetic particles and fusion alpha particles in tokamaks
The stability of high-n toroidicity-induced shear Alfven eigenmodes (TAE) in the presence of fusion alpha particles or energetic ions in tokamaks is investigated. The TAE modes are discrete in nature and thus can easily tap the free energy associated with energetic particle pressure gradient through wave particle resonant interaction. A quadratic form is derived for the high-n TAE modes using gyro-kinetic equation. The kinetic effects of energetic particles are calculated perturbatively using the ideal MHD solution as the lowest order eigenfunction. The finite Larmor radius (FLR) effects and the finite drift orbit width (FDW) effects are included for both circulating and trapped energetic particles. It is shown that, for circulating particles, FLR and FDW effects have two opposite influences on the stability of the high-n TAE modes. First, they have the usual stabilizing effects by reducing the wave particle interaction strength. Second, they also have destabilizing effects by allowing more particles to resonate with the TAE modes. It is found that the growth rate induced by the circulating alpha particles increase linearly with toroidal mode number n for small {kappa}{sub {theta}}{rho}{sub {alpha}}, and decreases as 1/n for {kappa}{sub {theta}}{rho}{sub {alpha}} {much gt} 1. The maximum growth rate is obtained at …
Date:
July 1, 1992
Creator:
Fu, G. Y. & Cheng, C. Z.
System:
The UNT Digital Library
Novel nanodispersed coal liquefaction catalysts: Molecular design via microemulsion-based synthesis
The objective of this project is to pursue the development of highly dispersed and inexpensive catalysts for improved coal solubilization and upgrading of coal liquids. A novel study of the synthesis of liquefaction catalysts of nanometer size will be carried out. It is based on the molecular design of reverse micelles (microemulsions). These surfactant-stabilized, metal-bearing microdrops offer unique opportunities for synthesizing very small particles by providing a cage-like effect that limits particle nucleation, growth and agglomeration. The emphasis will be on iron- and molybdenum-based catalysts, but the techniques to be developed should also be generally applicable. (VC)
Date:
July 1, 1991
Creator:
Osseo-Asare, K. & Radovic, L.R.
System:
The UNT Digital Library
On a quasi-isochronous B Factory in the PEP tunnel
Isochronous, or quasi-isochronous storage rings with very small momentum compaction factor {alpha} for various applications are discussed. This approach looks very promising for the B-Factory design. A small momentum compaction factor reduces the bunch length at the given RF voltage. A small bunch length allows, in principle, reduction of the beta function at the interaction point (IP) with a corresponding increase of the luminosity. However, achieving this is not easy due to difficulties with local chromatic effects at the IP, more severe background problems in the detector, and enhanced adverse effects of the beam-beam interaction. Although these problems can be addressed, they require substantial changes in the present design. It is worth noting that shorter bunches would also have larger energy losses and larger energy spread, due to wake field excitation and the smaller disruption parameter reducing the enhancement factor. But energy losses scale with the bunch length {sigma}{sub z} as {sigma}{sub z}{sup {minus}{1/2}}, remaining small compared with the losses due to synchrotron radiation. The disruption parameter is small in the present design anyway; hence, these effects do not cause additional problems.
Date:
July 1, 1991
Creator:
Heifets, S.
System:
The UNT Digital Library
An analysis of grazing incidence metal mirrors in a laser ICF reactor driver
Grazing incidence metal mirrors (GIMMs) are examined to replace dielectric mirrors for the final elements in a laser beam line for an inertial confinement fusion reactor. For a laser driver with a wavelength from 250 to 500 nm in a 10-ms pulse, irradiated mirrors made of Al, Al alloys, or Mg were found to have calculated laser damage limits of 0.3--2.3 J/cm{sup 2} of beam energy and neutron lifetime fluence limits of over 5 {times} 10{sup 20} 14 MeV n/cm{sup 2} when used at grazing incidence and operated at room temperature or at 77 K. A final focusing system including mirrors made of Al alloy 7475 at room temperature or at liquid nitrogen temperatures used with a driver which delivers 5 MJ of beam energy in 32 beams would require 32 mirrors of roughly 10 m{sup 2} each. This chapter includes calculations of damage limits for GIMMs and discusses critical issues relevant to the integrity and lifetime of such mirrors in a reactor environment. The reflectivities of various metals are calculated from measured optical constants at room temperature and at cryogenic temperatures for 250- to 500-nm light at both normal and grazing incidence. Then, for the mirrors in a representative …
Date:
July 12, 1991
Creator:
Bieri, R. & Guinan, M.
System:
The UNT Digital Library
Studies of human mutation rates
The three objectives of the program are: To isolate by the technique of two-dimensional polyacrylamide gel electrophoresis (2-D PAGE), proteins of special interest because of the relative mutability of the corresponding gene, establish the identity of the protein, and, for selected proteins, move to a characterization of the corresponding gene; To develop a more efficient approach, based on 2-D PAGE, for the detection of variants in DNA, with special reference to the identification of a variant in a child not present in either parent of the child (i.e., a mutation); and, To continue an effective interface with the genetic studies on the children of atomic bomb survivors in Japan, with reference to both the planning and implementation of new studies at the molecular level. For administrative purposes, the program is subdivided into four sections, each under the direction of one of the four co-PIs; the progress during the past year will be summarized in accordance with this sectional structure. 1 tab.
Date:
July 15, 1991
Creator:
Neel, J.V.
System:
The UNT Digital Library
Installation restoration program: Hydrologic measurements with an estimated hydrologic budget for the Joliet Army Ammunition Plant, Joliet, Illinois. [Contains maps of monitoring well locations, topography and hydrologic basins]
Hydrologic data were gathered from the 36.8-mi{sup 2} Joliet Army Ammunition Plant (JAAP) located in Joliet, Illinois. Surface water levels were measured continuously, and groundwater levels were measured monthly. The resulting information was entered into a database that could be used as part of numerical flow model validation for the site. Deep sandstone aquifers supply much of the water in the JAAP region. These aquifers are successively overlain by confining shales and a dolomite aquifer of Silurian age. This last unit is unconformably overlain by Pleistocene glacial tills and outwash sand and gravel. Groundwater levels in the shallow glacial system fluctuate widely, with one well completed in an upland fluctuating more than 17 ft during the study period. The response to groundwater recharge in the underlying Silurian dolomite is slower. In the upland recharge areas, increased groundwater levels were observed; in the lowland discharge areas, groundwater levels decreased during the study period. The decreases are postulated to be a lag effect related to a 1988 drought. These observations show that fluid at the JAAP is not steady-state, either on a monthly or an annual basis. Hydrologic budgets were estimated for the two principal surface water basins at the JAAP site. …
Date:
July 1, 1991
Creator:
Diodato, D. M.; Cho, H. E. & Sundell, R. C.
System:
The UNT Digital Library
Enhancing the use of coals by gas reburning-sorbent injection
The objective of this project is to evaluate and demonstrate a cost effective emission control technology for acid rain precursors, oxides of nitrogen (NO{sub x}) and sulfur (SO{sub x}), on two coal fired utility boilers in Illinois. The units selected are representative of pre-NSPS design practices: tangential and cyclone fired. Work on a third unit, wall fired, is on hold'' because of funding limitations. The specific objectives are to demonstrate reductions of 60 percent in NO{sub x} and 50 percent in SO{sub x} emissions, by a combination of two developed technologies, gas reburning (GR) and sorbent injection (SI). With GR, about 80{endash}85 percent of the coal fuel is fired in the primary combustion zone. The balance of the fuel is added downstream as natural gas to create a slightly fuel rich environment in which NO{sub x} is converted to N{sub 2}. The combustion process is completed by overfire air addition. SO{sub x} emissions are reduced by injecting dry sorbents (usually calcium based) into the upper furnace. The sorbents trap SO{sub x} as solid sulfates that are collected in the particulate control device.
Date:
July 19, 1990
Creator:
unknown
System:
The UNT Digital Library
HEATING 7. 1 user's manual
HEATING is a FORTRAN program designed to solve steady-state and/or transient heat conduction problems in one-, two-, or three- dimensional Cartesian, cylindrical, or spherical coordinates. A model may include multiple materials, and the thermal conductivity, density, and specific heat of each material may be both time- and temperature-dependent. The thermal conductivity may be anisotropic. Materials may undergo change of phase. Thermal properties of materials may be input or may be extracted from a material properties library. Heating generation rates may be dependent on time, temperature, and position, and boundary temperatures may be time- and position-dependent. The boundary conditions, which may be surface-to-boundary or surface-to-surface, may be specified temperatures or any combination of prescribed heat flux, forced convection, natural convection, and radiation. The boundary condition parameters may be time- and/or temperature-dependent. General graybody radiation problems may be modeled with user-defined factors for radiant exchange. The mesh spacing may be variable along each axis. HEATING is variably dimensioned and utilizes free-form input. Three steady-state solution techniques are available: point-successive-overrelaxation iterative method with extrapolation, direct-solution (for one-dimensional or two-dimensional problems), and conjugate gradient. Transient problems may be solved using one of several finite-difference schemes: Crank-Nicolson implicit, Classical Implicit Procedure (CIP), Classical Explicit Procedure …
Date:
July 1, 1991
Creator:
Childs, K.W.
System:
The UNT Digital Library
Development of improved iron Fischer-Tropsch catalysts
The objective of proposed research is development of catalysts with enhanced slurry phase activity and better selectivity to fuel range products, through a more detailed understanding and systematic studies of the effects of pretreatment procedures and promoters/binders (silica) on catalyst performance.
Date:
July 19, 1991
Creator:
Bukur, D.B.
System:
The UNT Digital Library