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Ensemble: 1998-07-15 - North Texas Conductor's Collegium
Band concert performed at the UNT College of Music Recital Hall.
Date:
July 15, 1998
Creator:
AETC Band of the West
Object Type:
Sound
System:
The UNT Digital Library
Biological Monitoring Program for East Fork Poplar Creek
In May 1985, a National Pollutant Discharge Elimination System (NPDES) permit was issued for the Oak Ridge Y-12 Plant. As a condition of the permit, a Biologicai Monitoring and Abatement Program (BMAP) was developed to demonstrate that the effluent limitations established for the Y-12 Plant protect the classified uses of the receiving stream (East Fork Poplar Creek; EFPC), in particular, the growth and propagation of aquatic life (Lear et al. 1989). A second objective of the BMAP is to document the ecological effects resulting from the implementation of a water pollution control program designed to eliminate direct discharges of wastewaters to EFPC and to minimize the inadvertent release of pollutants to the environment. Because of the compiex nature of the discharges to EFPC and the temporal and spatial variability in the composition of the discharges, a comprehensive, integrated approach to biological monitoring was developed. A new permit was issued to the Y-12 Plant on April 28, 1995 and became effective on July 1, 1995. Biological monitoring continues to be required under the new permit. The BMAP consists of four major tasks that reflect different but complementary approaches to evaluating the effects of the Y-12 Plant discharges on the aquatic integrity …
Date:
October 15, 1998
Creator:
Adams, S. M.; Christensen, S. W.; Greeley, M. S. Jr.; Hill, W. R.; Kszos, L. A.; McCarthy, J. F. et al.
Object Type:
Report
System:
The UNT Digital Library
Proton Decay Studies of the Light Lu, Tm and Ho Isotopes
A double-sided Si-strip detector system has been installed and commissioned at the focal plane of the Recoil Mass Spectrometer at the Holifield Radioactive Ion Beam Facility. The system can be used for heavy charged particle emission studies with half-lives as low as a few {micro}sec. In this paper the authors present identification and study of the decay properties of the five new proton emitters: {sup 140}Ho, {sup 141m}Ho, {sup 145}Tm, {sup 150m}Lu and {sup 151m}Lu.
Date:
October 15, 1998
Creator:
Akovali, Y.; Batchelder, J. C.; Bingham, C. R.; Davinson, T.; Ginter, T. N.; Gross, C. J. et al.
Object Type:
Article
System:
The UNT Digital Library
Investigation of syngas interactions in alcohol synthesis catalyst
The primary objectives of the project are to (a) synthesize, by controlled sequential and co-impregnation techniques, three distinct composition metal clusters (consisting of Cu-Co-Cr and Cu-Fe-Zn): rich in copper (Methanol selective), rich in ferromagnetic metal (Co or Fe-Hydrocarbon selective) and intermediate range (mixed alcohol catalysts); (b) investigate the changes in the magnetic character of the systems due to interaction with CO, through Zero-field Nuclear Magnetic Resonance (ZFNMR) study of cobalt and Magnetic character (saturation magnetization and coercive field) analysis of the composite catalyst of Vibrating Sample Magnetometry (VSM); (c) examine the changes in syngas adsorption character of the catalyst as the composition changes, by FTIR Spectroscopic analysis of CO stretching frequencies; (d) determine the nature and size of these intermetallic clusters by Scanning Electron Microscopy (SEM); and (e) perform catalytic runs on selected samples and analyze the correlations between the physical and chemical characteristics. The catalysts chosen have a greater promise for industrial application than the Rh and Mo based catalysts. Several groups preparing catalysts by synthetic routes have reported divergent results for activity and selectivity. Generally the research has followed an empirical path and less effort is devoted to analyze the mechanisms and the scientific basis. The primary intent …
Date:
April 15, 1998
Creator:
Akundi, M. A.
Object Type:
Report
System:
The UNT Digital Library
Oral History Interview with Colonel John. E. Olson, March 15, 1998
Access:
Use of this item is restricted to the UNT Community
Interview with Colonel John E. Olson, a Army WWII veteran and POW from Leavenworth, Kansas. Olson discusses his family background, commissioning in the Army from West Point, assignment to the Philippines in 1939 as an infantry officer, the start of the war, withdrawal to Bataan and the ensuing battle and surrender, the Bataan Death March, internment at Cabanatuan, transfer to Osaka, experiences there in internment at a factory labor camp, liberation, organizing the evacuation of POWs, returning to the US, and his postwar career.
Date:
March 15, 1998
Creator:
Alexander, Bill & Olson, John E.
Object Type:
Book
System:
The UNT Digital Library
Oral History Interview with Raymond F. "Hap" Halloran, March 15, 1998
Access:
Use of this item is restricted to the UNT Community
Interview with Raymond F. "Hap" Halloran, businessman and U.S. Army Air Force WWII Veteran (878th Bomb Squadron, 499th Bomb Group, 73rd Bomb Wing, 20th Air Force) concerning his experiences as a prisoner-of-war of the Japanese during World War II.
Date:
March 15, 1998
Creator:
Alexander, William J. & Halloran, Raymond F.
Object Type:
Book
System:
The UNT Digital Library
The Oklahoma Daily (Norman, Okla.), Vol. 83, No. 24, Ed. 1 Tuesday, September 15, 1998
Student newspaper of the University of Oklahoma in Norman, Oklahoma that includes national, local, and campus news along with advertising.
Date:
September 15, 1998
Creator:
Allam, Heather
Object Type:
Newspaper
System:
The Gateway to Oklahoma History
The Oklahoma Daily (Norman, Okla.), Vol. 83, No. 45, Ed. 1 Thursday, October 15, 1998
Student newspaper of the University of Oklahoma in Norman, Oklahoma that includes national, local, and campus news along with advertising.
Date:
October 15, 1998
Creator:
Allam, Heather
Object Type:
Newspaper
System:
The Gateway to Oklahoma History
Dynamic Fiber Optic Sensors Under Intense Radioactive Environments
A liquid mercury target will be used as the neutron source for the proposed Spallation Neutron Source facility. This target is subjected to bombardment by short-pulse, high-energy proton beams. The intense thermal loads caused by interaction of the pulsed proton beam with the mercury create an enormous rate of temperature rise ({approximately}10{sup 7} K/s) during a very brief beam pulse ({approximately } 0.5 {micro}s). The resulting pressure waves in the mercury will interact with the walls of the mercury target and may lead to large stresses. To gain confidence in the mercury target design concept and to benchmark the computer design codes, we tested various electrical and optical sensors for measuring the transient strains on the walls of a mercury container and the pressures in the mercury. The sensors were attached on several sample mercury targets that were tested at various beam facilities: Oak Ridge Electron Linear Accelerator, Los Alamos Neutron Science Center-Weapons Neutron Research, and Brookhaven National Laboratory's Alternating Gradient Synchrotron. The effects of intense background radiation on measured signals for each sensor are described and discussed. Preliminary results of limited tests at these facilities indicate that the fiber optic sensors function well in this intense radiation environment, whereas …
Date:
October 15, 1998
Creator:
Allison, S. W.; Earl, D. D.; Haines, J. R. & Tsai, C. C.
Object Type:
Article
System:
The UNT Digital Library
A sparse superlinearly convergent SQP with applications to two-dimensional shape optimization.
Discretization of optimal shape design problems leads to very large nonlinear optimization problems. For attaining maximum computational efficiency, a sequential quadratic programming (SQP) algorithm should achieve superlinear convergence while preserving sparsity and convexity of the resulting quadratic programs. Most classical SQP approaches violate at least one of the requirements. We show that, for a very large class of optimization problems, one can design SQP algorithms that satisfy all these three requirements. The improvements in computational efficiency are demonstrated for a cam design problem.
Date:
April 15, 1998
Creator:
Anitescu, M.
Object Type:
Article
System:
The UNT Digital Library
Archer County News (Archer City, Tex.), No. 3, Ed. 1 Thursday, January 15, 1998
Weekly newspaper from Archer City, Texas that includes local, state and national news along with advertising.
Date:
January 15, 1998
Creator:
Armstrong, Sonny
Object Type:
Newspaper
System:
The Portal to Texas History
Enzyme catalysts for a biotechnology-based chemical industry. Quarterly progress report, September 29--December 28, 1997
The goal of this research is to engineer enzymes to be efficient and economically attractive catalysts for the chemical industry. The author is attempting to demonstrate generally-applicable approaches to enzyme improvement as well as develop specific catalysts for potential industrial application. In this report attention is focused on random mutagenesis of pNB esterase -- improved activity and stability. The most thermostable esterases obtained by sequential random mutagenesis (6H7) and random mutagenesis plus recombination (6sF9) each contain 9 amino acid mutations and a number of silent mutations, relative to the wild-type sequence. Eight of the mutations are present in both genes, for a total of ten potentially adaptive mutations. Because several of these mutations occurred in the same generation, it is difficult to identify the mutations responsible for the increases in activity and stability. In order to aid in this identification, the thermostable genes were recombined with the wild-type gene, in hopes of removing neutral mutations. The gene from the first-generation variant, with five amino acid substitutions was also recombined with wild-type.
Date:
January 15, 1998
Creator:
Arnold, F.H.
Object Type:
Report
System:
The UNT Digital Library
Low-(18)O Silicic Magmas: Why Are They So Rare?
LOW-180 silicic magmas are reported from only a small number of localities (e.g., Yellowstone and Iceland), yet petrologic evidence points to upper crustal assimilation coupled with fractional crystallization (AFC) during magma genesis for nearly all silicic magmas. The rarity of 10W-l `O magmas in intracontinental caldera settings is remarkable given the evidence of intense 10W-l*O meteoric hydrothermal alteration in the subvolcanic remnants of larger caldera systems. In the Platoro caldera complex, regional ignimbrites (150-1000 km3) have plagioclase 6180 values of 6.8 + 0.1%., whereas the Middle Tuff, a small-volume (est. 50-100 km3) post-caldera collapse pyroclastic sequence, has plagioclase 8]80 values between 5.5 and 6.8%o. On average, the plagioclase phenocrysts from the Middle Tuff are depleted by only 0.3%0 relative to those in the regional tuffs. At Yellowstone, small-volume post-caldera collapse intracaldera rhyolites are up to 5.5%o depleted relative to the regional ignimbrites. Two important differences between the Middle Tuff and the Yellowstone 10W-180 rhyolites elucidate the problem. Middle Tuff magmas reached water saturation and erupted explosively, whereas most of the 10W-l 80 Yellowstone rhyolites erupted effusively as domes or flows, and are nearly devoid of hydrous phenocrysts. Comparing the two eruptive types indicates that assimilation of 10W-180 material, combined with …
Date:
October 15, 1998
Creator:
Balsley, Steven D. & Gregory, Robert T.
Object Type:
Article
System:
The UNT Digital Library
News Bulletin (Castroville, Tex.), Vol. 39, No. 42, Ed. 1 Thursday, October 15, 1998
Weekly newspaper from Castroville, Texas that includes local, state, and national news along with extensive advertising.
Date:
October 15, 1998
Creator:
Barnes, Thomas
Object Type:
Newspaper
System:
The Portal to Texas History
Designs Studies of Low-Aspect Ratio Quasi-Omnigenous Stellarators
Significant progress has been made in the development of new modest-size compact stellarator devices that could test optimization principles for the design of a more attractive reactor. These are 3 and 4 field period low-aspect-ratio quasi-omnigenous (QO) stellarators based on an optimization method that targets improved confinement, stability, ease of coil design, low-aspect-ratio, and low bootstrap current.
Date:
October 15, 1998
Creator:
Batchelor, D. B.; Carreras, B. A.; Hirshman, S. P.; Lynch, V. E.; Sanchez, R.; Spong, D. A. et al.
Object Type:
Article
System:
The UNT Digital Library
Comparison of Analytical and Experimental Effectiveness of Four-Row Plate-Fin-Tube Heat Exchangers with Water, R-22, and R-410A
The analytical solutions of heat exchanger effectiveness for four-row crcmilow, cross-countertlow and cross-paralleltlow have been derived in the recent study. The main objective of this study is to investigate the etlkct of heat exchawger tlow conllguration on thermal performance with refrigerant mixtures. Difference of heat exchanger effectiveness for all flow arrangements relative to an analytical many-row solution has been analyzed. A comparison of four-row cross cou~ltet-ilow heat exchanger effectiveness between analytical solutions and experimental data with water, R-22, and R-4 10A is presented.
Date:
November 15, 1998
Creator:
Baxter, V. D.; Chen, T. D. & Conklin, J. C.
Object Type:
Article
System:
The UNT Digital Library
Decontamination of Radionuclides from Concrete During and After Thermal Treatment
The objective was to clarify from the theoretical viewpoint the mechanical, diffusional, thermodynamic and electromagnetic aspects of the decontaminations problem, by means of developing a powerful computational model to evaluate the effect of a very rapid heating regime on the on the contaminated concrete walls or slabs. The practical objective was to assess the feasibility of the microwave heating scheme envisaged and determine its suitable parameters such as power and duration. This objective was complementary to, but separate from, the chemical and nuclear aspects of long-time processes that led to the contamination and various conceivable alternative methods of decontamination which were investigated by Dr. Brian Spalding of Oak Ridge National Laboratory, with whom the start-up phase of this project was coordinated.
Date:
September 15, 1998
Creator:
Bazant, Z. P.
Object Type:
Report
System:
The UNT Digital Library
An Efficient Molecular Dynamics Scheme for Predicting Dopant Implant Profiles in Semiconductors
The authors present a highly efficient molecular dynamics scheme for calculating the concentration profile of dopants implanted in group-IV alloy, and III-V zinc blende structure materials. The program incorporates methods for reducing computational overhead, plus a rare event algorithm to give statistical accuracy over several orders of magnitude change in the dopant concentration. The code uses a molecular dynamics (MD) model, instead of the binary collision approximation (BCA) used in implant simulators such as TRIM and Marlowe, to describe ion-target interactions. Atomic interactions are described by a combination of 'many-body' and screened Coulomb potentials. Inelastic energy loss is accounted for using a Firsov model, and electronic stopping is described by a Brandt-Kitagawa model which contains the single adjustable parameter for the entire scheme. Thus, the program is easily extensible to new ion-target combinations with the minimum of tuning, and is predictive over a wide range of implant energies and angles. The scheme is especially suited for calculating profiles due to low energy, large angle implants, and for situations where a predictive capability is required with the minimum of experimental validation. They give examples of using their code to calculate concentration profiles and 2D 'point response' profiles of dopants in crystalline …
Date:
September 15, 1998
Creator:
Beardmore, K.M. & Gronbech-Jensen, N.
Object Type:
Article
System:
The UNT Digital Library
BF-4618: Tactical VTOL UAV at Yuma Proving Grounds
Video clip from a test flight of the Bell Eagle Eye, an unmanned aerial vehicle that the company offered as part of the Navy's VT-UAV (Vertical Takeoff-Unmanned Aerial Vehicle) program.
Date:
April 15, 1998
Creator:
Bell Helicopter Textron
Object Type:
Video
System:
The UNT Digital Library
Magnetic anisotropy and its microstructural origin in epitaxially grown SmCo thin films.
Microstructural features and magnetic behavior of epitaxially grown SmCo thin films with very high in-plane anisotropy are presented. Transmission electron microscopy was used to characterize the microstructure while magnetic measurements were performed using dc and SQUID magnetometers. Two substrate orientations were studied, i.e., MgO(100)/Cr(100)/SmCo(11{bar 2}0) and MgO(110)/Cr(211)/SmCo(1{bar 1}00). In the former, the SmCo(11{bar 2}0) film shows a bicrystalline microstructure, whereas in the latter, a uniaxial one is observed. Both microstructure consist of grains with a mixture of SmCo{sub 3} , Sm{sub 2}Co{sub 7} and SmCo{sub 3} polytypoids. A deviation from the c-axes was observed in the in-plane anisotropy of the SmCo(11{bar 2}0) thin film. A strong exchange interaction between the grains would, in principle, explain the observed deviation. On the other hand, both SmCo(11{bar 2}0) and (1{bar 1}00) thin films show very high coercivity values with pinning-type characteristics. Possible coercivity mechanisms related to intergranular exchange interactions and local variation in magnetocrystalline anisotropy constants are discussed.
Date:
April 15, 1998
Creator:
Benaissa, M.
Object Type:
Article
System:
The UNT Digital Library
TAE Saturation of Alpha Particle Driven Instability in TFTR
A nonlinear theory of kinetic instabilities near threshold [H.L. Berk, et al., Plasma Phys. Rep. 23, (1997) 842] is applied to calculate the saturation level of Toroidicity-induced Alfvén Eigenmodes (TAE) and be compared with the predictions of (delta)f method calculations [Y. Chen, Ph.D. Thesis, Princeton University, 1998]. Good agreement is observed between the predictions of both methods and the predicted saturation levels are comparable with experimentally measured amplitudes of the TAE oscillations in TFTR [D.J. Grove and D.M. Meade, Nucl. Fusion 25, (1985) 1167].
Date:
September 15, 1998
Creator:
Berk, H. L.; Chen, Y.; Gorelenkov, N. N. & White, R. B.
Object Type:
Report
System:
The UNT Digital Library
Cryogenic D-T fuel layers formed in 1mm spheres by beta-layering
Solid D-T fuel smoothly layered on the interior of spherical capsules is required for all inertial confinement fusion ignition target designs. One process for forming these layers, beta-layering, has been studied in surrogate geometries such as open cylinders or tori to allow accurate characterization of the DT surfaces. We present the first results from beta layering in 1 mm spherical containers, such as will be used in upcoming Omega experiments. These results are also directly relevant to ignition capsules for the National Ignition Facility. We find that layers can form with roughness as small as 1.2 microns rms, and that results are strongly dependent upon freezing rate as well as layer thickness.
Date:
October 15, 1998
Creator:
Bernat, T. P.; Burmann, J.; Collins, G. W.; Kozioziemski, B.; Mapoles, E. R.; Pipes, J. et al.
Object Type:
Article
System:
The UNT Digital Library
In-Situ Tritium Beta Detector
The objectives of this three-phase project were to design, develop, and demonstrate a monitoring system capable of detecting and quantifying tritium in situ in ground and surface waters, and in water from effluent lines prior to discharge into public waterways. The tritium detection system design is based on measurement of the low energy beta radiation from the radioactive decay of tritium using a special form of scintillating optical fiber directly in contact with the water to be measured. The system consists of the immersible sensor module containing the optical fiber, and an electronics package, connected by an umbilical cable. The system can be permanently installed for routine water monitoring in wells or process or effluent lines, or can be moved from one location to another for survey use. The electronics will read out tritium activity directly in units of pico Curies per liter, with straightforward calibration. In Phase 1 of the project, we characterized the sensitivity of fluor-doped plastic optical fiber to tritium beta radiation. In addition, we characterized the performance of photomultiplier tubes needed for the system. In parallel with this work, we defined the functional requirements, target specifications, and system configuration for an in situ tritium beta detector …
Date:
April 15, 1998
Creator:
Berthold, J. W. & Jeffers, L. A.
Object Type:
Report
System:
The UNT Digital Library
Phase 1 Final Report for In-Situ Tritium Beta Detector
The objectives of this three-phase project were to design, develop, and demonstrate a monitoring system capable of detecting and quantifying tritium in situ in ground and surface waters, and in water from effluent lines prior to discharge into public waterways. The tritium detection system design is based on measurement of the low energy beta radiation from the radioactive decay of tritium using a special form of scintillating optical fiber directly in contact with the water to be measured. The system consists of the immersible sensor module containing the optical fiber, and an electronics package, connected by an umbilical cable. The system can be permanently installed for routine water monitoring in wells or process or effluent lines, or can be moved from one location to another for survey use. The electronics will read out tritium activity directly in units of pico Curies per liter, with straightforward calibration. In Phase 1 of the project, we characterized the sensitivity of fluor-doped plastic optical fiber to tritium beta radiation. In addition, we characterized the performance of photomultiplier tubes needed for the system. In parallel with this work, we defined the functional requirements, target specifications, and system configuration for an in situ tritium beta detector …
Date:
April 15, 1998
Creator:
Berthold, J. W. & Jeffers, L. A.
Object Type:
Report
System:
The UNT Digital Library