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Office of Scientific & Technical Information Technical Reports
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97
Texas Patents
56
Texas Attorney General Opinions
46
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42
Technical Report Archive and Image Library
17
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15
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11
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Equipoise-2: A Two-Dimensional, Two-Group, Neutron-Diffusion Code for the IBM-7090 Computer
Equipoise-2, a two-dimensional, two-group neutron-diffusion code in R-Z geometry, has been programmed for the IBM-7090 computer. This code was designed to permit the running of large numbers of cases without requiring excessive machine time. Typical running times are of the order of one to three minutes per case for a 1000-point problems. The maximum number of mesh points that can be used is 1444.
Date:
November 21, 1960
Creator:
Fowler, T. B. & Tobias, Melvin
Object Type:
Report
System:
The UNT Digital Library
Newsletter of Texas State Representative Ernest Bailes: Volume 1, Issue 11, November 2017
Newsletter of Ernest Bailes for his constituents in district 18 discussing news, activities, and various updates related to work in the Texas legislature. It focuses on Bailes expressing the things his thankfulness for the legislative accomplishments in district 18.
Date:
November 21, 2017
Creator:
Bailes, Ernest James, IV
Object Type:
Journal/Magazine/Newsletter
System:
The Portal to Texas History
Servo System for Magnetic Controlled Constant Intensity Flat Top Beam Spill-Out
A uniform intensity flat top spill-out cannot be obtained by manual control for two reasons: 1. The horizontal density of the internal beam of the Cosmotron is far from uniform. As a result, a manually controlled linear motion of the internal beam into a target will result in a non-uniform spill-out intensity. 2. Stability requirements of the Cosmotron magnet voltage are not easily met without feedback because of inherent component stability. The proposed servo system will sense the external beam intensity, and correct the magnet voltage to keep this intensity constant. This servo must operate through the transfer function of the main ignitron system and the flat top filter. Both of those transfer functions impose special problems.
Date:
November 21, 1961
Creator:
Cottingham, J. G.
Object Type:
Report
System:
The UNT Digital Library
A Review of the MPC's for Natural Thorium
The possible hazards from the refining and processing of thorium are of wide interest in atomic energy work. A review of the data available was made at Hanford in the last year to support consultations on the hazards of radioisotopes with other plants which may handle thorium. Since a major discrepancy between the published values of air MPC's and the metabolic data was noted, a review of the calculations on thorium was made in order to obtain the best estimates available. This document tabulates the pertinent data and applies them to the calculation of the MPC of thorium.
Date:
November 21, 1955
Creator:
Healy, J. W.
Object Type:
Report
System:
The UNT Digital Library
A Sensitive Particle Ionization Chamber for Neutron Detection
Abstract. A particle ionization chamber of sensitivity sufficient to detect a source of one neutron per second has been used to measure the neutron yield from a thick target of sulfur upon bombardment with polonium alpha particles. The high-geometry boron trifluoride chamber used had an efficiency of 1.9 percent for fission neutrons. The neutron yield from a thick target of sulfur was measured by this instrument and found to be .0035 +- .0013 neutrons per million incident polonium alpha particles.
Date:
November 21, 1944
Creator:
Sturm, William J. & Dabbs, John
Object Type:
Report
System:
The UNT Digital Library
Vehicle.
Patent for improvements to vehicle structure. This includes adjustments to the wheel base for better steering movements and vehicle capacity.
Date:
November 21, 1922
Creator:
Furlong, Martin J.
Object Type:
Patent
System:
The Portal to Texas History
Knee Pad.
Patent for an improved knee pad, which provides better ventilation and cushioning to the knee, including illustrations.
Date:
November 21, 1922
Creator:
Rylander, Parrish H.
Object Type:
Patent
System:
The Portal to Texas History
Device for Washing Oil Wells.
Patent for "a device for washing, cleaning, and sterilizing oil wells" (lines 10-11), including illustrations.
Date:
November 21, 1922
Creator:
Smith, Edward D. & Smith, Rebah Tillery
Object Type:
Patent
System:
The Portal to Texas History
Argonne National Laboratory Biology Division Quarterly Report: August to October, 1946
From introductory paragraph: "This is the first quarterly report of the Biology Division of the Argonne National Laboratory. During the three-month period covered by this report, a large share of the time of many investigators has been spent in collating work done under the Biology Section of the Metallurgical laboratory for publication in the Plutonium Project Record. The large amount of work done under wartime pressure has made this, as in other divisions and projects, an important part of the transition to the post-war period."
Date:
November 21, 1946
Creator:
Bruss, Austin M.
Object Type:
Report
System:
The UNT Digital Library
Pelletizing/reslurrying as a means of distributing and firing clean coal
The objective of this study is to develop technology that permits the practical and economic preparation, storage, handling, and transportation of coal pellets, which can be reslurried into Coal water fuels (CWF) suitable for firing in small- and medium-size commercial and industrial boilers, furnaces, and engines. The project includes preparing coal pellets and capsules from wet filter cake that can be economically stored, handled, transported, and reslurried into a CWF that can be suitably atomized and fired at the user site. The wet cakes studied were prepared from ultra-fine (95% -325 mesh) coal beneficiated by advanced froth-flotation techniques. The coals studied included two eastern bituminous coals, one from Virginia (Elkhorn) and one from Illinois (Illinois No. 6) and one western bituminous coal from Utah (Sky Line coal).
Date:
November 21, 1991
Creator:
Conkle, H. N.; Raghavan, J. K.; Smit, F. J. & Jha, M. C.
Object Type:
Report
System:
The UNT Digital Library
Evaluation of BeO ceramic disks for thermally stimulated exoelectron dosimetry
BeO ceramic disks were evaluated for application as dosimeters for both penetrating and non-penetrating radiation. Response to penetrating radiation was measured as thermoluminescence (TL) and to non-penetrating radiation as thermally stimulated exoelectron emission (TSEE). Field experiments demonstrated that both TSEE and TL responses from BeO can monitor diverse radiation fields. BeO disks in a passive dosimeter were found to be sensitive to a lower exposure level of 100 pCi-day/liter of radon. The depth of the more active exoelectron layer in BeO was found to be 4 ..mu..m. A second less active, exoelectron layer extends to a depth of at least 16 ..mu..m.
Date:
November 21, 1975
Creator:
Bush, J. R.; Keeler, J. B. & Piret, J. J.
Object Type:
Report
System:
The UNT Digital Library
Programs to control motor vehicle emissions in the state of Texas
Report on reducing motor vehicle emissions in Texas. Contains recommendations, technical results, discussions, and estimations of emissions.
Date:
November 21, 1980
Creator:
Texas Air Control Board
Object Type:
Report
System:
The Portal to Texas History
Texas Preventable Disease News, Volume 47, Number 46, November 21, 1987
Newsletter of the Texas Bureau of Disease Control and Epidemiology discussing the news, activities, and events of the organization and other information related to health in Texas.
Date:
November 21, 1987
Creator:
Texas. Bureau of Disease Control and Epidemiology.
Object Type:
Journal/Magazine/Newsletter
System:
The Portal to Texas History
An Examination of the Effects of Be Grain Size
During the WBS4 review almost a year ago in January, and in more recent discussions of needed capsule characterization, I was struck by three pieces of information related to machined Be capsules: (1) that the speed of sound (and perhaps other properties) in Be grains is markedly different in orthogonal directions, (2) that the grain size in the best refined bulk Be samples is 10 to 15 {micro}m, and that these grains in the best case are randomly oriented, and (3) that we are concerned about capsule homogeneity on the level of 1 part in 10{sup 4}, presumably over angular length scales corresponding to the maximum in the growth curve. It seems to me that the first two points might be inconsistent with the third, and this led me to attempt to model the effect of randomly oriented Be grains on the radially dependent properties of a capsule.
Date:
November 21, 2000
Creator:
Cook, R
Object Type:
Report
System:
The UNT Digital Library
Efficient Multi-keV X-ray Sources from Ti-doped Aerogel Targets
We have measured the production of h{nu} {ge} 4.5 keV x-rays from low-density Ti-doped aerogel targets at the OMEGA laser facility (University of Rochester). The doped-foam density was {approx} 3 mg/cc. Forty beams of the OMEGA laser ({lambda}{sub L} = 0.351 {micro}m) illuminated the two cylindrical faces of the target with a total power that ranged from 7 to 14 TW. The laser interaction fully ionizes the target (n{sub e}/n{sub crit} {ge} 0.1), and allows the laser-bleaching wave to excite, supersonically, the high-Z emitter ions in the sample. Ti K-shell x-ray emission was spectrally resolved with a two-channel crystal spectrometer and also with a set of filtered aluminum x-ray diodes, both instruments provide absolute measurement of the multi-keV x-ray emission. Back-scattered laser energy is observed to be minimal. We find between 40 - 260 J of output with 4.67 {le} h{nu} {le} 5.0 keV.
Date:
November 21, 2003
Creator:
Satcher, J.; Fournier, K.; Suter, L.; Davis, J.; Back, C.; Grun, J. et al.
Object Type:
Article
System:
The UNT Digital Library
Hydrogeologic Unit Flow Characterization Using Transition Probability Geostatistics
This paper describes a technique for applying the transition probability geostatistics method for stochastic simulation to a MODFLOW model. Transition probability geostatistics has several advantages over traditional indicator kriging methods including a simpler and more intuitive framework for interpreting geologic relationships and the ability to simulate juxtapositional tendencies such as fining upwards sequences. The indicator arrays generated by the transition probability simulation are converted to layer elevation and thickness arrays for use with the new Hydrogeologic Unit Flow (HUF) package in MODFLOW 2000. This makes it possible to preserve complex heterogeneity while using reasonably sized grids. An application of the technique involving probabilistic capture zone delineation for the Aberjona Aquifer in Woburn, Ma. is included.
Date:
November 21, 2003
Creator:
Jones, N L; Walker, J R & Carle, S F
Object Type:
Article
System:
The UNT Digital Library
Precision Manufacturing of Inertial Confinement Fusion Double Shell Laser Targets for OMEGA
Double shell targets have been built by Lawrence Livermore National Laboratory (LLNL) for inertial confinement fusion (ICF) experiments on the Omega laser at the University of Rochester and as a prelude to similar experiments on NIF. Of particular interest to ICF studies are high-precision double shell implosion targets for demonstrating thermonuclear ignition without the need for cryogenic preparation. Because the ignition tolerance to interface instabilities is rather low, the manufacturing requirements for smooth surface finishes and shell concentricity are particularly strict. This paper describes a deterministic approach to manufacturing and controlling error sources in each component. Included is the design philosophy of why certain manufacturing techniques were chosen to best reduce the errors within the target. The manufacturing plan developed for this effort created a deterministic process that, once proven, is repeatable. By taking this rigorous approach to controlling all error sources during the manufacture of each component and during assembly, we have achieved the overall 5 {micro}m dimensional requirement with sub-micron surface flaws. Strengths and weaknesses of the manufacturing process will be discussed.
Date:
November 21, 2003
Creator:
Amendt, P. A.; Bono, M. J.; Hibbard, R. L.; Castro, C. & Bennett, D. W.
Object Type:
Article
System:
The UNT Digital Library
Hydrogen isotope exchange in metal hydride columns
Several metal hydrides were shown to act as chromatographic media for hydrogen isotopes. The procedure was to equilibrate a column of hydride with flowing hydrogen, inject a small quantity of tritium tracer, and observe its elution behavior. Characteristic retention times were found. From these and the extent of widening of the tritium band, the heights equivalent to a theoretical plate could be calculated. Values of around 1 cm were obtained. The following are the metals whose hydrides were studied, together with the temperature ranges in which chromatographic behavior was observed: vanadium, 0 to 70/sup 0/C; zirconium, 500 to 600/sup 0/C; LaNi/sub 5/, -78 to +30/sup 0/C; Mg/sub 2/Ni, 300 to 375/sup 0/C; palladium, 0 to 70/sup 0/C. A dual-temperature isotope separation process based on hydride chromatography was demonstrated. In this, a column was caused to cycle between two temperatures while being supplied with a constant stream of tritium-traced hydrogen. Each half-cycle was continued until ''breakthrough,'' i.e., until the tritium concentration in the effluent was the same as that in the feed. Up to that point, the effluent was enriched or depleted in tritium, by up to 20%.
Date:
November 21, 1977
Creator:
Wiswall, R.; Reilly, J.; Bloch, F. & Wirsing, E.
Object Type:
Report
System:
The UNT Digital Library
Are Published Minimum Vapor Phase Spark Ignition Energy Data Valid?
The use of sprayed flammable fluids as solvents in dissolution and cleaning processes demand detailed understanding of ignition and fire hazards associated with these applications. When it is not feasible to inert the atmosphere in which the spraying process takes place, then elimination of all possible ignition sources must be done. If operators are involved in the process, the potential for human static build-up and ultimate discharge is finite, and it is nearly impossible to eliminate. The specific application discussed in this paper involved the use of heated Dimethyl Sulfoxide (DMSO) to dissolve high explosives (HE). Search for properties of DMSO yielded data on flammability limits and flash point, but there was no published information pertaining to the minimum energy for electrical arc ignition. Due to the sensitivity of this procedure, The Hazards Control Department of Lawrence Livermore National Laboratory (LLNL) was tasked to determine the minimum ignition energy of DMSO aerosol and vapor an experimental investigation was thus initiated. Because there were no electrical sources in spray chamber, Human Electro-Static Discharge (HESD) was the only potential ignition source. Consequently, the electrostatic generators required for this investigation were designed to produce electrostatic arcs with the defined voltage and current pulse …
Date:
November 21, 2001
Creator:
Staggs, K J; Alvares, N J & Greenwood, D W
Object Type:
Article
System:
The UNT Digital Library
Towards An Ideal Slow Cookoff Model For PBXN-109
We present an overview of computational techniques for simulating the thermal cookoff of high explosives using a multi-physics hydrodynamics code, ALE3D. Recent improvements to the code have aided our computational capability in modeling the response of energetic materials systems exposed to extreme thermal environments, such as fires. We consider an idealized model process for a confined explosive involving the transition from slow heating to rapid deflagration in which the time scale changes from days to hundreds of microseconds. The heating stage involves thermal expansion and decomposition according to an Arrhenius kinetics model while a pressure-dependent burn model is employed during the explosive phase. We describe and demonstrate the numerical strategies employed to make the transition from slow to fast dynamics. In addition, we investigate the sensitivity of wall expansion rates to numerical strategies and parameters. Results from a one-dimensional model show increased violence when the gap between the explosive and steel vessel is removed.
Date:
November 21, 2003
Creator:
Wardell, J. F.; Maienschein, J. L.; Yoh, J. J.; Nichols, A. L. & McClelland, M. A.
Object Type:
Article
System:
The UNT Digital Library
Freshwater Flow Charts - 1995
This report covers the following: (1) Explanation of Charts Showing Freshwater Flow in 1995; (2) Estimated U.S. Freshwater Flow in 1995 (chart); (3) Estimated California Freshwater Flow in 1995 (chart); (4) Estimated New Mexico Freshwater Flow in 1995 (chart); and (5) Web locations and credits.
Date:
November 21, 2003
Creator:
Kaiper, G V
Object Type:
Report
System:
The UNT Digital Library
The effect of area size and predation on the time to extinction of prairie vole populations. simulation studies via SERDYCA: a Spatially-Explicit Individual-Based Model of Rodent Dynamics
We present a spatially-explicit individual-based computational model of rodent dynamics, customized for the prairie vole species, M. Ochrogaster. The model is based on trophic relationships and represents important features such as territorial competition, mating behavior, density-dependent predation and dispersal out of the modeled spatial region. Vegetation growth and vole fecundity are dependent on climatic components. The results of simulations show that the model correctly predicts the overall temporal dynamics of the population density. Time-series analysis shows a very good match between the periods corresponding to the peak population density frequencies predicted by the model and the ones reported in the literature. The model is used to study the relation between persistence, landscape area and predation. We introduce the notions of average time to extinction (ATE) and persistence frequency to quantify persistence. While the ATE decreases with decrease of area, it is a bell-shaped function of the predation level: increasing for 'small' and decreasing for 'large' predation levels.
Date:
November 21, 2003
Creator:
Kostova, T & Carlsen, T
Object Type:
Article
System:
The UNT Digital Library
Electrical Resistivity Modeling of a Permeable Reactive Barrier for Vista Engineering Technologies: Summary
We have performed a numerical modeling study that evaluated the capacity of electrical resistance tomography (ERT) to detect flaws in a passive reactive barrier (PRB). The model barrier is based on a real barrier described in the literature Slater and Binley (2003). It consists of highly conducting, granular iron emplaced within a trench. We assumed that the barrier was filled with a mixture of iron and sand, and that vertical electrode arrays were embedded within the barrier. We have considered (a) characterization and (b) monitoring scenarios. For (a), the objective is to use tomographs of absolute resistivity to detect construction flaws and inhomogeneities in iron distribution shortly after installation. For (b), the objective is to use resistivity change tomographs to detect iron oxidation and barrier plugging as a function of time. The study considered varying PRB hole sizes and locations. For any given model, a hole was located right next to and near the center of an electrode array (maximum sensitivity and resolution expected), at the center between two electrode arrays (moderate sensitivity and resolution), or near the bottom centered between the two arrays (minimum sensitivity and resolution). We also considered various hole sizes. The smallest hole considered had a …
Date:
November 21, 2003
Creator:
Ramirez, A L & Daily, W D
Object Type:
Report
System:
The UNT Digital Library
Low-Temperature Aging and Phase Stability of U6Nb
Aging behavior and phase stability of a water-quenched U-6wt%Nb (U-14at%Nb) alloy artificially aged at 200 C and naturally aged at ambient temperature for 15 years have been investigated using Vickers hardness test, X-ray diffraction analysis, and transmission electron microscopy techniques. Age hardening/softening phenomenon is observed from the artificially aged samples according to microhardness measurement. The age hardening can be rationalized by the occurrence of spinodal decomposition, or fine scale of Nb segregation, which results in the formation of a nano-scale modulated structure within the artificially aged samples. Coarsening of the modulated structure after prolonged aging leads to the age softening. The occurrence of chemical ordering (disorder-order transformation) is found in the naturally aged sample based upon the observations of antiphase domain boundaries (APB's) and superlattice diffraction patterns. A possible superlattice structure is accordingly proposed for the chemically ordered phase observed in the naturally aged alloy sample.
Date:
November 21, 2003
Creator:
Hsiung, L M; Briant, C L & Chasse, K R
Object Type:
Article
System:
The UNT Digital Library