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178
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53
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47
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37
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27
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METHODOLOGY, ASSUMPTIONS, AND BASELINE DATA FOR THE REPOSITORY DESIGN AND OPERATION, RAIL CORRIDORS, AND HEAVY TRUCK ROUTES, CLARK COUNTY, NEVADA, LINCOLN COUNTY, NEVADA, NYE COUNTY, NEVADA, "REST OF NEVADA", STATE OF NEVADA
None
Date:
January 25, 2002
Creator:
/a, n
Object Type:
Report
System:
The UNT Digital Library
Suits Against Terrorist States
None
Date:
January 25, 2002
Creator:
Ackerman, David M.
Object Type:
Report
System:
The UNT Digital Library
Effects of Particulate Debris Morphology on the Rolling Wear Behavior of All-Steel and Si(Sub 3)N(Sub 4)-Steel Bearing Element Couples
Rolling contact fatigue experiments were performed on all-steel and hybrid Si{sub 3}N{sub 4}-M50 steel rolling bearing systems using particulate contaminated lubricants. The particulate contaminants used were glycothermally synthesized {alpha}-Al{sub 2}O{sub 3} platelets or Arizona test dust. The effects of contaminant composition and morphology on rolling contact fatigue and wear behavior were explored. The effects of bearing element material properties on fatigue and wear behavior were also examined. Rolling wear behavior is related to bearing component material configuration and the type of particulate contaminant present in the lubricant. Component and particulate material properties such as hardness and elastic modulus are observed to affect rolling wear behavior. Wear mechanisms such as contact stress fatigue, indenting, cutting and plowing are observed.
Date:
January 25, 1999
Creator:
Adair, J.H.; Mecholsky, J.J., Jr. & Mitchell, D.J.
Object Type:
Article
System:
The UNT Digital Library
Fundamental Studies of Recombinant Hydrogenases
This research addressed the long term goals of understanding the assembly and organization of hydrogenase enzymes, of reducing them in size and complexity, of determining structure/function relationships, including energy conservation via charge separation across membranes, and in screening for novel H2 catalysts. A key overall goal of the proposed research was to define and characterize minimal hydrogenases that are produced in high yields and are oxygen-resistant. Remarkably, in spite of decades of research carried out on hydrogenases, it is not possible to readily manipulate or design the enzyme using molecular biology approaches since a recombinant form produced in a suitable host is not available. Such resources are essential if we are to understand what constitutes a “minimal” hydrogenase and design such catalysts with certain properties, such as resistance to oxygen, extreme stability and specificity for a given electron donor. The model system for our studies is Pyrococcus furiosus, a hyperthermophile that grows optimally at 100°C, which contains three different nickel-iron [NiFe-] containing hydrogenases. Hydrogenases I and II are cytoplasmic while the other, MBH, is an integral membrane protein that functions to both evolve H2 and pump protons. Three important breakthroughs were made during the funding period with P. furiosus soluble …
Date:
January 25, 2014
Creator:
Adams, Michael W
Object Type:
Report
System:
The UNT Digital Library
CENRTC Project {number_sign}2F3EOA, OCB A-376, acceptance test procedure
This test procedure provides the steps necessary to verify correct functional operation of controls, annunciators, alarms, protective relays and related systems impacted by CENRTC {number_sign}2F3E0A, Microwave Transfer Trip Project, modification work performed under work package 6B-93-00041/M. This procedure separates three tests into separate sections: energization of A-376 duplex panel and circuits; SCADA tests; and A-376 local trip tests.
Date:
January 25, 1995
Creator:
Akerson, A. W.
Object Type:
Report
System:
The UNT Digital Library
Novel reactor configuration for synthesis gas conversion to alcohols
Our objectives during this quarter was to complete studies on the kinetics of methanol synthesis reaction in the slurry reactor with long periods of on stream studies, start experimentation in the trickle bed reactor assembly, investigate simulation studies using the piston-exchange (PE) and piston-dispersion-exchange (PDE) models, and introduce water gas shift reaction as the second reaction in our simulation studies.
Date:
January 25, 1992
Creator:
Akgerman, A. & Anthony, R. G.
Object Type:
Report
System:
The UNT Digital Library
Novel reactor configuration for synthesis gas conversion to alcohols. Quarterly report, October 1, 1991--December 31, 1991
Our objectives during this quarter was to complete studies on the kinetics of methanol synthesis reaction in the slurry reactor with long periods of on stream studies, start experimentation in the trickle bed reactor assembly, investigate simulation studies using the piston-exchange (PE) and piston-dispersion-exchange (PDE) models, and introduce water gas shift reaction as the second reaction in our simulation studies.
Date:
January 25, 1992
Creator:
Akgerman, A. & Anthony, R. G.
Object Type:
Report
System:
The UNT Digital Library
Status of the SPARC Project
The SPARC project has entered its installation phase at the Frascati National Laboratories of INFN: its main goal, the promotion of an R&D activity oriented to the development of a high brightness photoinjector to drive SASE-FEL experiments, is being vigorously pursued by a collaboration among ENEA-INFN-CNR-Universita di Roma Tor Vergata-INFM-ST. In this paper we will report on the installation and test of some major components, like Ti:Sa laser system, RF gun and RF power system. Advancements in the control and beam diagnostics systems will also be reported, in particular on the emittance-meter device for beam emittance measurements in the drift space downstream the RF gun. Recent results on laser pulse shaping show the feasibility of producing 10 ps flat-top laser pulses in the UV with rise time below 1 ps. First FEL experiments have been proposed, using SASE, seeding and non-linear resonant harmonics.
Date:
January 25, 2006
Creator:
Alesini, D.; Bertolucci, S.; Bellaveglia, M.; Biagini, M.E.; Boni, R.; Boscolo, M. et al.
Object Type:
Article
System:
The UNT Digital Library
Wire - Fence Machine.
Patent for a new and useful wire-fence machine. This design is to "provide a simple, compact, light, and comparatively inexpensive machine adapted to be transported with facility to enable a single operator to readily distribute" (line 10 - 13).
Date:
January 25, 1898
Creator:
Allen, John W.
Object Type:
Patent
System:
The Portal to Texas History
Optical Properties of InGaAsN: A New 1eV Bandgap Material System
InGaAsN is a new semiconductor alloy system with the remarkable property that the inclusion of only 2% nitrogen reduces the bandgap by more than 30%. In order to help understand the physical origin of this extreme deviation from the typically observed nearly linear dependence of alloy properties on concentration, we have investigated the pressure dependence of the excited state energies using both experimental and theoretical methods. We report measurements of the low temperature photohnninescence energy of the material for pressures between ambient and 110 kbar. We describe a simple, density-functional-theory-based approach to calculating the pressure dependence of low lying excitation energies for low concentration alloys. The theoretically predicted pressure dependence of the bandgap is in excellent agreement with the experimental data. Based on the results of our calculations, we suggest an explanation for the strongly non-linear pressure dependence of the bandgap that, surprisingly, does not involve a nitrogen impurity band. Addhionally, conduction-band mass measurements, measured by three different techniques, will be described and finally, the magnetoluminescence determined pressure coefficient for the conduction-band mass is measured.
Date:
January 25, 1999
Creator:
Allerman, A. A.; Fritz, I. J.; Jones, E. D.; Kurtz, S. R.; Modine, N. A.; Tozer, S. T. et al.
Object Type:
Article
System:
The UNT Digital Library
Embodied Energy and Off-Grid Lighting
The greenhouse gas (GHG) emissions from fuel-based lighting are substantial given the paltry levels of lighting service provided to users, leading to a great opportunity for GHG mitigation byencouraging the switch from fuel-based to rechargeable LED lighting. However, as with most new energy technology, switching to efficient lighting requires an up-front investment of energy(and GHGs) embedded in the manufacture of replacement components. We studied a population of off-grid lighting users in 2008-2009 in Kenya who were given the opportunity to adopt LEDlighting. Based on their use patterns with the LED lights and the levels of kerosene offset we observed, we found that the embodied energy of the LED lamp was"paid for" in only one month for grid charged products and two months for solar charged products. Furthermore, the energyreturn-on investment-ratio (energy produced or offset over the product's service life divided by energy embedded) for off-grid LED lighting ranges from 12 to 24, which is on par with on-gridsolar and large-scale wind energy. We also found that the energy embodied in the manufacture of a typical hurricane lantern is about one-half to one-sixth of that embodied in the particular LEDlights that we evaluated, indicating that the energy payback time would be …
Date:
January 25, 2011
Creator:
Alstone, Peter; Mills, Evan & Jacobson, Arne
Object Type:
Report
System:
The UNT Digital Library
An Investigation of Cross-Borehole Ground Penetrating Radar Measurements for Characterizing the 2D Moisture Content Distribution in the Vadose Zone
The use of cross-borehole ground penetrating radar (GPR) imaging for determining g the two dimensional (2D) in situ moisture content distribution within the vadose zone is being investigated. The ultimate goal is to use the GPR images as input to a 2D hydrologic inversion scheme for recovering the van Genuchten parameters governing unsaturated ,hydraulic flow. Initial experiments conducted on synthetic data have shown that at least in theory, cross-borehole GPR measurements can provide realistic estimates of the spatial variation in moisture content that are needed for this type of hydrologic inversion scheme. However, the method can not recover exact values of moisture content due to the break down of the empirical expression often employed to convert GPR velocity images to moisture content, and to the smearing nature of the imaging algorithm. To test the applicability of this method in a real world environment cross- borehole GPR measurements were made at a hydrologic/geophysical vadose zone test site in Socorro, New Mexico. Results show that the GPR images compare well with the uncalibrated borehole neutron log data. GPR data acquisition will continue once an infiltration test has started, and the results from these measurements will be employed in a 2D hydrologic inverse …
Date:
January 25, 1999
Creator:
Alumbaugh, D. & Paprocki, L.
Object Type:
Article
System:
The UNT Digital Library
Bench scale testing of micronized magnetite beneficiation. Quarterly technical progress report 4, October--December, 1993
This project is aimed at development of a process that, by using ultra fine magnetite suspension, would expand the application of heavy media separation technology to processing fine, {minus}28 mesh coals. These coal fines, produced during coal mining and crushing, are separated in the conventional coal preparation plant and generally impounded in a tailings pond. Development of an economic process for processing these fines into marketable product will expand the utilization of coal for power production in an environmentally acceptable and economically viable way. This process has been successfully researched at PETC but has not been studied on a continuous bench-scale unit, which is a necessary step towards commercial development of this promising technology. The goal of the program is to investigate the technology in a continuous circuit at a reasonable scale to provide a design basis for larger plants and a commercial feasibility data.
Date:
January 25, 1994
Creator:
Anast, K.
Object Type:
Report
System:
The UNT Digital Library
Prediction of the Inert Strength Distribution of Si3N4 Diesel Valves
Censored Weibull strength distributions were generated with NT551 silicon nitride four-point flexure data using the ASTM C1161-B and 5.0 mm diameter cylindrical specimens. Utilizing finite element models and AlliedSignal's life prediction codes, the inert or fast fracture strength failure probability of a ceramic diesel valve was estimated from these data sets. The failure probability prediction derived from each data set were found to be more conservative than valve strength data. Fractographic analysis of the test specimens and valves showed that the cylindrical specimens failed from a different flaw population than the prismatic flexure bars and the valves. The study emphasizes the prerequisite of having coincident flaw populations homogeneously distributed in both the test specimen and the ceramic component. Lastly, it suggests that unless material homogeneity exists, that any meaningful life prediction or reliability analysis of a component may not be possible.
Date:
January 25, 1999
Creator:
Andrews, M. J.; Breder, K. & Wereszczak, A. A.
Object Type:
Article
System:
The UNT Digital Library
Continuum-based FEM modeling of ceramic powder compaction using a cap-plasticity constitutive model
Common ceramic component manufacturing typically involves the processing of the raw materials in powder form. Granulated powder is formed into a green body of the desired size and shape by consolidation, often by simply pressing nominally dry powder. Ceramic powders are commonly pressed in steel dies or rubber bags with the aim of producing a near-net-shape green body for subsequent sintering. Density gradients in these compacts, introduced during the pressing operation, are often severe enough to cause distortions in the shape of the part during sintering due to nonuniform shrinkage. In such cases, green machining or diamond grinding operations may be needed to obtain the desired final shape and size part. In severe cases, nonuniform shrinkage may even cause fracture in the parts during sintering. Likewise, density gradients can result in green bodies that break during ejection from the die or that are too fragile to be handled during subsequent processing. Empirical relationships currently exist to describe powder compaction but provide little understanding of how to control die design or compaction parameters to minimize density gradients thereby forcing the designer to use expensive and time consuming trial and error procedures. For this reason, interest has grown in developing computational tools …
Date:
January 25, 2000
Creator:
Arguello, Jose G., Jr.; Fossum, Arlo F.; Zeuch, David H. & Ewsuk, Kevin G.
Object Type:
Article
System:
The UNT Digital Library
Measurement of the B+- to rho pi0 Branching Fraction and Direct CP Asymmetry
The authors present improved measurements of the branching fraction and CP asymmetry for the process B{sup {+-}} {yields} {rho}{sup {+-}}{pi}{sup 0}. The data sample corresponding to 211 fb{sup -1} comprises 232 million {Upsilon}(4S) {yields} B{bar B} decays collected with the BABAR detector at the PEP-II asymmetric B Factory at SLAC. The yield and CP asymmetry are measured using an extended maximum likelihood fitting method. The branching fraction and Cp asymmetry are found to be {Beta}(B{sup {+-}} {yields} {rho}{sup {+-}}{pi}{sup 0}) = [10.2 {+-} 1.4(stat) {+-} 0.9(syst)] x 10{sup -6} and {Alpha}{sub CP}(B{sup {+-}} {yields} {rho}{sup {+-}}{pi}{sup 0}) = -0.01 {+-} 0.13(stat) {+-} 0.02(syst).
Date:
January 25, 2007
Creator:
Aubert, B.
Object Type:
Article
System:
The UNT Digital Library
Beryllium Sampling and Analysis Within the DOE Complex and Opportunities for Standardization
Since the U. S. Department of Energy (DOE) published the DOE Beryllium Rule (10 CFR 850) in 1999, DOE sites have been required to measure beryllium on air filters and wipes for worker protection and for release of materials from beryllium-controlled areas. Measurements in the nanogram range on a filter or wipe are typically required. Industrial hygiene laboratories have applied methods from various analytical compendia, and a number of issues have emerged with sampling and analysis practices. As a result, a committee of analytical chemists, industrial hygienists, and laboratory managers was formed in November 2003 to address the issues. The committee developed a baseline questionnaire and distributed it to DOE sites and other agencies in the U.S. and U.K. The results of the questionnaire are presented in this paper. These results confirmed that a wide variety of practices were in use in the areas of sampling, sample preparation, and analysis. Additionally, although these laboratories are generally accredited by the American Industrial Hygiene Association (AIHA), there are inconsistencies in performance among accredited labs. As a result, there are significant opportunities for development of standard methods that could improve consistency. The current availabilities and needs for standard methods are further discussed in …
Date:
January 25, 2005
Creator:
BRISSON, MICHAEL
Object Type:
Article
System:
The UNT Digital Library
Review of The SIAM 100-Digit Challenge: A Study in High-Accuracy Numerical Computing
In the January 2002 edition of SIAM News, Nick Trefethen announced the '$100, 100-Digit Challenge'. In this note he presented ten easy-to-state but hard-to-solve problems of numerical analysis, and challenged readers to find each answer to ten-digit accuracy. Trefethen closed with the enticing comment: 'Hint: They're hard! If anyone gets 50 digits in total, I will be impressed.' This challenge obviously struck a chord in hundreds of numerical mathematicians worldwide, as 94 teams from 25 nations later submitted entries. Many of these submissions exceeded the target of 50 correct digits; in fact, 20 teams achieved a perfect score of 100 correct digits. Trefethen had offered $100 for the best submission. Given the overwhelming response, a generous donor (William Browning, founder of Applied Mathematics, Inc.) provided additional funds to provide a $100 award to each of the 20 winning teams. Soon after the results were out, four participants, each from a winning team, got together and agreed to write a book about the problems and their solutions. The team is truly international: Bornemann is from Germany, Laurie is from South Africa, Wagon is from the USA, and Waldvogel is from Switzerland. This book provides some mathematical background for each problem, and …
Date:
January 25, 2005
Creator:
Bailey, David
Object Type:
Report
System:
The UNT Digital Library
Practical superconductor development for electrical power applications - annual report for FY 2000.
Most large-scale high-critical-temperature superconductor applications require wires or tapes that an carry high currents in applied magnetic fields. This report describes technical progress of research and development efforts aimed at producing superconducting components and devices in the Y-Ba-Cu-O and Bi-(Pb)-Sr-Ca-Cu-O systems. Topics discussed are formation of first- and second-generation composite conductors, characterization of structures and superconducting and mechanical properties, modeling of grain-boundary current transport, and fabrication and analysis of prototype components.
Date:
January 25, 2001
Creator:
Balachandran, U.; Cha, Y. S.; Dorris, S. E.; Dusek, J. T.; Emerson, J. E.; Fisher, B. L. et al.
Object Type:
Report
System:
The UNT Digital Library
Advanced microinstrumentation for rapid DNA sequencing and large DNA fragment separation
Our efforts to develop novel technology for a rapid DNA sequencer and large fragment analysis system based upon gel electrophoresis are described. We are using microfabrication technology to build dense arrays of high speed micro electrophoresis lanes that will ultimately increase the sequencing rate of DNA by at least 100 times the rate of current sequencers. We have demonstrated high resolution DNA fragment separation needed for sequencing in polyacrylamide microgels formed in glass microchannels. We have built prototype arrays of microchannels having up to 48 channels. Significant progress has also been made in developing a sensitive fluorescence detection system based upon a confocal microscope design that will enable the diagnostics and detection of DNA fragments in ultrathin microchannel gels. Development of a rapid DNA sequencer and fragment analysis system will have a major impact on future DNA instrumentation used in clinical, molecular and forensic analysis of DNA fragments.
Date:
January 25, 1995
Creator:
Balch, J.; Davidson, J.; Brewer, L.; Gingrich, J.; Koo, J.; Mariella, R. et al.
Object Type:
Report
System:
The UNT Digital Library
Specimen Size Effect on the Creep of Si3N4
The effect of specimen size on the measured tensile creep behavior of a commercially available gas pressure sintered Si3N4 was examined. Button-head tensile test specimens were used for the testing, and were machined to a variety of different gage section diameters (ranging from 2.5 to 6.35 mm) or different surface-area-to-volume ratios. The specimens were then creep tested at 1350 Degrees C and 200 MPa with tensile creep strain continuously measured as a function of time. The steady-state creep rate increased and the lifetime decreased with an increase in diameter (or decrease in the ratio of gage section surface area to volume). The time and specimen size dependence of transformation of a secondary phase correlated with the observed creep rate and lifetime dependence.
Date:
January 25, 1999
Creator:
Barnes, A. S.; Ferber, M. K.; Kirkland, T. P. & Wereszczak, A. A.
Object Type:
Article
System:
The UNT Digital Library
PNNL OS3300 Alpha/Beta Monitoring System Software and Hardware Operations Manual, Revision 0
This Pacific Northwest National Laboratory (PNNL) OS3300 Alpha/Beta Monitoring System Software and Hardware Operations Manual describes how to install and operate the software and hardware on a personal computer in conjunction with the EG&G Berthold LB150D continuous air monitor. Included are operational details for the software functions, how to read and use the drop-down menus, how to understand readings and calculations, and how to access the database tables.
Date:
January 25, 2006
Creator:
Barnett, J. M.; Duchsherer, Cheryl J.; Sisk, Daniel R.; Carter, Gregory L.; Douglas, David D. & Carrell, Dorothy M.
Object Type:
Report
System:
The UNT Digital Library
Applications of advanced petroleum production technology and water alternating gas injection for enhanced oil recovery: Mattoon Oil Field, Illinois. Fourth quarterly report, [October 1, 1993--December 31, 1993]
The objectives of this project are to continue reservoir characterization of the Cypress Sandstone; to identify and map fades-defined waterflood units (FDWS); and to design and Implement water-alternating-gas (WAG) oil recovery utilizing carbon dioxide (CO{sub 2}). The producibility problems are permeability variation and poor sweep efficiency. Phase 1 of the project focuses on the development of computer-generated geological and reservoir simulation models that will be used to select sites for the demonstration and implementation of CO{sub 2} displacement programs in Phase 2. Included in Phase 1 is the site selection and drilling of an infill well, coring of the Cypress interval, and injectivity testing to gather information used to update the reservoir simulation model. Phase 2 involves field implementation of WAG. Technology Transfer includes outreach activity such as seminars, workshops, and field trips. Technical progress for this quarter is described.
Date:
January 25, 1994
Creator:
Baroni, M.
Object Type:
Report
System:
The UNT Digital Library
Investigation of Stresses Due to Thermal Gradients in Typical Aircraft Structures
Memorandum presenting an investigation of a series of five 75S-T6 aluminum-alloy elementary skin and spar-cap combinations with skin varying from 0.051 to 0.500 inch in thickness to determine the temperature and stress gradients resulting from the application of heat to the surface. The data are presented in the form of tables of the measured temperatures and stresses calculated from the measured strains.
Date:
January 25, 1952
Creator:
Barzelay, Martin E. & Boison, James C.
Object Type:
Report
System:
The UNT Digital Library