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Center for volcanic and tectonic studies, Department of Geoscience, Univ. of Nevada, Las Vegas, NV. Annual report No. 69, October 1, 1991--September 30, 1992

Description: The annual report of the Center for Volcanic and Tectonic Studies (CVTS) contains a series of papers, maps, and reprints that review the progress made by the CVTS between October 1, 1991 and December 31, 1992. During this period CVTS staff focused on several topics that had direct relevance to volcanic hazards related to the proposed high-level nuclear waste repository at Yucca Mountain, Nevada. These topics included: (1) The role of the mantle during regional extension. (2) The structural controls and emplacement mechanisms of Pliocene/Quaternary basaltic centers and dikes. (3) The detailed geochemistry of individual volcanic centers in Crater Flat, Nevada. (4) Estimating the probability of disruption of the proposed repository by volcanic eruption (this topic is being studied by Dr. C-H. Ho at UNLV).
Date: December 15, 1992
Creator: Smith, E.I.
Partner: UNT Libraries Government Documents Department

The design and construction of the muon arm in PHENIX. Progress report, December 15, 1994--December 1, 1995

Description: The purpose of this report is to describe activities performed by the Intermediate Energy Nuclear Physics Group (IENPG) at the Louisiana State University (LSU). During the preceding year the authors have been actively involved with three collaborations--the PHENIX Collaboration, the DLS Collaboration, and the E866 Collaboration at Fermilab--that are the foci of their activities. In addition they are members of a fourth collaboration, the AMY Collaboration at KEK, and in concert with other members of that collaboration they are working diligently to terminate all its ongoing activities. The first three collaborations are discussed here.
Date: December 15, 1995
Creator: Kirk, P.N.
Partner: UNT Libraries Government Documents Department

Engineering Development of Coal-Fired High-Performance Power Systems

Description: The concept uses a pyrolyzation process to convert coal into fuel gas and char. The char is fired in a High Temperature Advanced Furnace (HITAF). It is a pulverized fuel- fired boiler/ air heater where steam and gas turbine air are indirectly heated. The fuel gas generated in the pyrolyzer is then used to heat the gas turbine air further before it enters the gas turbine. The project is currently in Phase 2 which includes engineering analysis, laboratory testing and pilot plant testing. Research and development is being done on the HIPPS systems that are not commercial or being developed on other projects. Pilot plant testing of the pyrolyzer subsystem and the char combustion subsystem are being done separately, and then a pilot plant with a more integrated HIPPS arrangement will be tested. The High Performance Power System is a coal- fired, combined cycle power generating system that will have an efficiency of greater than 47 percent (HHV) with NOx and SOx less than 0.025 Kg/ GJ (0.06 lb/ MMBtu). This performance is achieved by combining a coal pyrolyzation process with a High Temperature Advanced Furnace (HITAF). The pyrolyzation process consists of a pressurized fluidized bed reactor which is operated at about 926 o C (1700 o F) at substoichiometric conditions. This process converts the coal into a low- Btu fuel gas and char. These products are then separated. The char is fired in the HITAF where heat is transferred to the gas turbine compressed air and to the steam cycle. The HITAF is fired at atmospheric pressure with pulverized fuel burners. The combustion air is from the gas turbine exhaust stream. The fuel gas from the pyrolyzation process is fired in a Multi- Annular Swirl Burner (MASB) where it further heats the gas turbine air leaving the HITAF. This ...
Date: December 15, 1997
Creator: Shenker, J.
Partner: UNT Libraries Government Documents Department

Development and testing of a high efficiency advanced coal combustor Phase III industrial boiler retrofit. Quarterly technical progress report, July 1, 1995--September 30, 1995 No. 16

Description: The objective of this project is to retrofit a burner, capable of firing microfine coal, to a standard gas/oil designed industrial boiler to assess the technical and economic viability of displacing premium fuels with microfine coal. This report documents the technical aspects of this project during the sixteenth quarter (July `95 through September `95) of the program. The overall program has consisted of five major tasks: (1) A review of current state-of-the-art coal firing system components. (2) Design and experimental testing of a prototype HEACC (High Efficiency Advanced Coal Combustor) burner. (3) Installation and testing of a prototype HEACC system in a commercial retrofit application. (4) Economics evaluation of the HEACC concept for retrofit applications. (5) Long term demonstration under commercial user demand conditions.
Date: December 15, 1995
Creator: Borio, R.W.
Partner: UNT Libraries Government Documents Department

Kinetics of Mn-based sorbents for hot coal gas desulfurization. Quarterly progress report, September 15, 1995--December 15, 1995

Description: The Morgantown Energy Technology Center (METC) of the U.S. Department of Energy (DOE) is actively pursuing the development of reliable and cost-effective processes to clean coal gasifier gases for application to integrated gasification combined cycle (IGCC) and molten carbonate fuel cell (MCFC) power plants. A large portion of gas cleanup research has been directed towards hot gas desulfurization using Zn-based sorbents. However, zinc titanate sorbents undergo reduction to the metal at temperatures approaching 700{degrees}C and lose reactivity because of volatilization. In addition, sulfate formation during regeneration leads to spalling of reactive surfaces. Because of these problems with zinc-based sorbents, METC has shown interest in formulating and testing manganese-based sorbents. Currently, many proposed IGCC processes include a water quench prior to desulfurization. This quench is required for two reasons; limitations in the process hardware (1000{degrees}C), and excessive Zn-based sorbent loss (about 700{degrees}C). With manganese, the water quench is not necessary to avoid sorbent loss, since Mn-based sorbents have been shown to retain reactivity under cyclic testing at 900{degrees}C. This advantage of manganese over zinc has potential to increase thermal efficiency as the trade-off of increasing the equilibrium H{sub 2}S over-pressure obtainable with a manganese sorbent. In the work which is reported here, lower loading temperatures (as low as 400{degrees}C) are studied. Also formulations containing titania rather then alumina are studied to attempt to improve performance.
Date: December 15, 1995
Creator: Hepworth, M.T. & Berns, J.
Partner: UNT Libraries Government Documents Department

Temperature-dependent tensile strength, surface roughness diagnostics, and magnetic support and positioning of polymer ICF shells. Final report, October 1, 1993--April 30, 1995

Description: During the course of this grant, we perfected emissivity and accommodation coefficient measurements on polymer ICF shells in the temperature range 250 to 350 K. Values for polystyrene shells are generally between 10{sup -2} and 10{sup -3}, which are very advantageous for ICF at cryogenic temperatures. Preliminary results on Br doped target shells indicate an accommodation coefficient, presumably associated with surface roughness on an atomic scale, about an order of magnitude larger than for ordinary polystyrene target shells. We also constructed apparatus with optical access for low temperature tensile strength and emissivity measurements, and made preliminary tests on this system. Magnetic shells were obtained both from GDP coating and from doping styrene with 10 manometer size ferromagnetic particles. The magnetic properties were measured through electron spin resonance (ESR). These experiments confirm the applicability of the Curie law, and establish the validity of using ESR measurements to determine shell temperature in the low temperature regime from 4K to 250K, thus complementing our presently accessible range. The high electron spin densities (> 10{sup 20}/CM{sup 3}) suggest magnetic levitation should be feasible at cryogenic temperatures. This work has resulted in two conference presentations, a Technical Report, a paper to be published in Fusion Technology, and a Master`s Thesis.
Date: December 15, 1995
Creator: Honig, A.
Partner: UNT Libraries Government Documents Department

Braze Process Optimization Involving Conventional Metal/Ceramic Brazing with 50Au-50Cu Alloy

Description: Numerous process variables can influence the robustness of conventional metal/ceramic brazing processes. Experience with brazing of hermetic vacuum components has identified the following parameters as influencing the outcome of hydrogen furnace brazed Kovar{trademark} to metallized alumina braze joints: (a) Mo-Mn metallization thickness, sinter fire temperature and porosity (b) Nil plate purity, thickness, and sinter firing conditions (c) peak process temperature, time above liquidus and (d) braze alloy washer thickness. ASTM F19 tensile buttons are being used to investigate the above parameters. The F19 geometry permits determination of both joint hermeticity and tensile strength. This presentation will focus on important lessons learned from the tensile button study: (A) the position of the Kovar{trademark} interlayer can influence the joint tensile strength achieved--namely, off-center interlayers can lead to residual stress development in the ceramic and degrade tensile strength values. Finite element analysis has been used to demonstrate the expected magnitude in strength degradation as a function of misalignment. (B) Time above liquidus (TAL) and peak temperature can influence the strength and alloying level of the resulting braze joint. Excessive TAL or peak temperatures can lead to overbraze conditions where all of the Ni plate is dissolved. (C) Metallize sinter fire processes can influence the morphology and strength obtained from the braze joints.
Date: December 15, 1999
Creator: MALIZIA JR.,LOUIS A.; MEREDITH,KEITH W.; APPEL,DANIEL B.; MONROE,SAUNDRA L.; BURCHETT,STEVEN N. & STEPHENS JR.,JOHN J.
Partner: UNT Libraries Government Documents Department

Monthly report, November, 1966

Description: This report gives summaries for the reactor plant operations, fuel and target fabrication, technical activities, advanced concepts and planning, and irradiation services. A feature report is included which describes the following: (1) the safety and control rod systems of the production reactors; (2) the problems which have developed with them; and (3) the corrective rod channel renovation and rod modification work which has been accomplished.
Date: December 15, 1966
Partner: UNT Libraries Government Documents Department

Preliminary study of lead isotopes in the carbonate-silica veins of Trench 14, Yucca Mountain, Nevada

Description: The sub-vertical carbonate-silica veins filling the Bow Ridge Fault, where exposed in Trench 14 on the east side of Yucca Mountain, carry a lead isotopic signature that can be explained in terms of local sources. Two isotopically distinguishable--silicate and carbonate--fractions of lead are recognized within the vein system as well as in overlying surficial calcrete deposits. The acid-insoluble silicate fraction is contributed largely from the decomposing Miocene volcanic tuff, which forms the wall rock of the fault zone and is a ubiquitous component of the overlying soil. Lead contained in the silicate fraction approaches in isotopic composition that of the Miocene volcanic rocks of Yucca Mountain, but diverges from it in some samples by being more enriched in uranogenic isotopes. The carbonate fraction of lead in both vein and calcrete samples resides dominantly in the HCl- and CH{sub 3}COOH-soluble calcite. HCl evidently also attacks and removes lead from silicate phases, but the milder CH{sub 3}COOH dissolution procedure oftentimes identifies a significantly more radiogenic lead in the calcite. Wind-blown particulate matter brought to the area from Paleozoic and Late Proterozoic limestones in surrounding mountains may be the ultimate source of the calcite. Isotopically more uniform samples suggest that locally the basaltic ash and other volcanic rock have contributed most of the lead to both fractions of the vein system. An important finding of this study is that the data does not require the more exotic mechanisms or origins that have been proposed for the veins. Instead, the remarkably similar lead isotopic properties of the veins to those of the soil calcretes support their interpretation as a surficial, pedogenic phenomenon.
Date: December 15, 1993
Creator: Zartman, R.E. & Kwak, L.M.
Partner: UNT Libraries Government Documents Department

Reactor outage schedule (tentative)

Description: This single page document is the December 15, 1970 reactor refueling outage schedule for the Hanford Production Reactor. It also contains data on the amounts and types of fuels to be loaded and relocated in the Production Reactor.
Date: December 15, 1970
Creator: Rowe, R.P.
Partner: UNT Libraries Government Documents Department

An Inertial-Fusion Z-Pinch Power Plant Concept

Description: With the promising new results of fast z-pinch technology developed at Sandia National Laboratories, we are investigating using z-pinch driven high-yield Inertial Confinement Fusion (ICF) as a fusion power plant energy source. These investigations have led to a novel fusion system concept based on an attempt to separate many of the difficult fusion engineering issues and a strict reliance on existing technology, or a reasonable extrapolation of existing technology, wherever possible. In this paper, we describe the main components of such a system with a focus on the fusion chamber dynamics. The concept works with all of the electrically-coupled ICF proposed fusion designs. It is proposed that a z-pinch driven ICF power system can be feasibly operated at high yields (1 to 30 GJ) with a relatively low pulse rate (0.01-0.1 Hz). To deliver the required current from the rep-rated pulse power driver to the z-pinch diode, a Recyclable Transmission Line (RTL) and the integrated target hardware are fabricated, vacuum pumped, and aligned prior to loading for each power pulse. In this z-pinch driven system, no laser or ion beams propagate in the chamber such that the portion of the chamber outside the RTL does not need to be under vacuum. Additionally, by utilizing a graded-density solid lithium or fluorine/lithium/beryllium eutectic (FLiBe) blanket between the source and the first-wall the system can breed its own fuel absorb a large majority of the fusion energy released from each capsule and shield the first-wall from a damaging neutron flux. This neutron shielding significantly reduces the neutron energy fluence at the first-wall such that radiation damage should be minimal and will not limit the first-wall lifetime. Assuming a 4 m radius, 8 m tall cylindrical chamber design with an 80 cm thick spherical FLiBe blanket, our calculations suggest that a 20 cm thick ...
Date: December 15, 2000
Creator: DERZON,MARK S.; ROCHAU,GARY E.; DEGROOT,J.; OLSON,CRAIG L.; PETERSON,P.; PETERSON,R.R. et al.
Partner: UNT Libraries Government Documents Department

Initial Screening of Thermochemical Water-Splitting Cycles for High Efficiency Generation of Hydrogen Fuels Using Nuclear Power

Description: OAK B188 Initial Screening of Thermochemical Water-Splitting Cycles for High Efficiency Generation of Hydrogen Fuels Using Nuclear Power There is currently no large scale, cost-effective, environmentally attractive hydrogen production process, nor is such a process available for commercialization. Hydrogen is a promising energy carrier, which potentially could replace the fossil fuels used in the transportation sector of our economy. Fossil fuels are polluting and carbon dioxide emissions from their combustion are thought to be responsible for global warming. The purpose of this work is to determine the potential for efficient, cost-effective, large-scale production of hydrogen utilizing high temperature heat from an advanced nuclear power station. Almost 800 literature references were located which pertain to thermochemical production of hydrogen from water and over 100 thermochemical watersplitting cycles were examined. Using defined criteria and quantifiable metrics, 25 cycles have been selected for more detailed study.
Date: December 15, 1999
Creator: Brown, L. C.; Funk, J. F. & Showalter, S. K.
Partner: UNT Libraries Government Documents Department

HNPF Cold Trap Evaluation

Description: Two designs of sodium cold traps for the HNPF have been subjected to full scale tests, Performance features that were investigated include oxide removal efficiency, oxide capacity, pressure drop characteristics, economizer effectiveness, and temperature profiles, Results indicate that both designs should perform satisfactorily in the Hallam plant, (auth)
Date: December 15, 1959
Creator: Cygan, R.
Partner: UNT Libraries Government Documents Department

Pakistan: U.S. Foreign Aid Conditions, Restrictions, and Reporting Requirements

Description: This report provides a comprehensive list of existing laws and pending legislation containing conditions, limitations, and reporting requirements for U.S. foreign assistance to Pakistan. It will track the debate on this topic and resulting changes.
Date: December 15, 2011
Creator: Epstein, Susan B. & Kronstadt , K. Alan
Partner: UNT Libraries Government Documents Department

Iran: U.S. Concerns and Policy Responses

Description: This report discusses the reasons that Iran is considered a threat to U.S. security, including Iran's nuclear program, involvement with terrorist organizations, and involvement with neighboring countries' local governments. The report also discusses ways which the U.S. hopes to modify Iran's behavior with sanctions, and the effectiveness of these sanctions.
Date: December 15, 2011
Creator: Katzman, Kenneth
Partner: UNT Libraries Government Documents Department

Epidemiology and etiology of Parkinson's disease

Description: This report provides introduction of Dr. James Parkinson, diagnosis of Parkinson's syndromes, the age of onset of the disease, racial origin and incidence rate of Parkinson's, as well as survival after the onset of Parkinson's.
Date: December 15, 1988
Creator: Rajput, A.H.
Partner: UNT Libraries Government Documents Department

CHEMICAL FIXATION OF CO2 IN COAL COMBUSTION PRODUCTS AND RECYCLING THROUGH BIOSYSTEMS

Description: This Annual Technical Progress Report presents the principle results in enhanced growth of algae using coal combustion products as a catalyst to increase bicarbonate levels in solution. A co-current reactor is present that increases the gas phase to bicarbonate transfer rate by a factor of five to nine. The bicarbonate concentration at a given pH is approximately double that obtained using a control column of similar construction. Algae growth experiments were performed under laboratory conditions to obtain baseline production rates and to perfect experimental methods. The final product of this initial phase in algae production is presented. Algal growth can be limited by several factors, including the level of bicarbonate available for photosynthesis, the pH of the growth solution, nutrient levels, and the size of the cell population, which determines the available space for additional growth. In order to supply additional CO2 to increase photosynthesis and algal biomass production, fly ash reactor has been demonstrated to increase the available CO2 in solution above the limits that are achievable with dissolved gas alone. The amount of dissolved CO2 can be used to control pH for optimum growth. Periodic harvesting of algae can be used to maintain algae in the exponential, rapid growth phase. An 800 liter scale up demonstrated that larger scale production is possible. The larger experiment demonstrated that indirect addition of CO2 is feasible and produces significantly less stress on the algal system. With better harvesting methods, nutrient management, and carbon dioxide management, an annual biomass harvest of about 9,000 metric tons per square kilometer (36 MT per acre) appears to be feasible. To sequester carbon, the algal biomass needs to be placed in a permanent location. If drying is undesirable, the biomass will eventually begin to aerobically decompose. It was demonstrated that algal biomass is a suitable feed ...
Date: December 15, 2003
Creator: Copeland, C. Henry; Pier, Paul; Whitehead, Samantha; Enlow, Paul; Strickland, Richard & Behel, David
Partner: UNT Libraries Government Documents Department

Neutrino telescopes as a direct probe of supersymmetrybreaking

Description: We consider supersymmetric models where the scale of supersymmetry breaking lies between 5 x 10{sup 6} GeV and 5 x 10{sup 8} GeV. In this class of theories, which includes models of gauge mediated supersymmetry breaking, the lightest supersymmetric particle is the gravitino. The next to lightest supersymmetric particle is typically a long lived charged slepton with a lifetime between a microsecond and a second, depending on its mass. Collisions of high energy neutrinos with nucleons in the earth can result in the production of a pair of these sleptons. Their very high boost means they typically decay outside the earth. We investigate the production of these particles by the diffuse flux of high energy neutrinos, and the potential for their observation in large ice or water Cerenkov detectors. The relatively small cross-section for the production of supersymmetric particles is partially compensated for by the very long range of heavy particles. The signal in the detector consists of two parallel charged tracks emerging from the earth about 100 meters apart, with very little background. A detailed calculation using the Waxman-Bahcall limit on the neutrino flux and realistic spectra shows that km{sup 3} experiments could see as many as 4 events a year. We conclude that neutrino telescopes will complement collider searches in the determination of the supersymmetry breaking scale, and may even give the first evidence for supersymmetry at the weak scale.
Date: December 15, 2003
Creator: Albuquerque, Ivone; Burdman, Gustavo & Chacko, Z.
Partner: UNT Libraries Government Documents Department

Catalyzed hydrogenation of nitrogen and ethylene on metal (Fe, Pt) single crystal surfaces and effects of coadsorption: A sum frequency generation vibrational spectroscopy study

Description: High-pressure catalytic reactions and associated processes, such as adsorption have been studied on a molecular level on single crystal surfaces. Sum Frequency Generation (SFG) vibrational spectroscopy together with Auger Electron Spectroscopy (AES), Temperature Programmed Desorption (TPD) and Gas Chromatography (GC) were used to investigate the nature of species on catalytic surfaces and to measure the catalytic reaction rates. Special attention has been directed at studying high-pressure reactions and in particular, ammonia synthesis in order to identify reaction intermediates and the influence of adsorbates on the surface during reaction conditions. The adsorption of gases N{sub 2}, H{sub 2}, O{sub 2} and NH{sub 3} that play a role in ammonia synthesis have been studied on the Fe(111) crystal surface by sum frequency generation vibrational spectroscopy using an integrated Ultra-High Vacuum (UHV)/high-pressure system. SFG spectra are presented for the dissociation intermediates, NH{sub 2} ({approx}3325 cm{sup -1}) and NH ({approx}3235 cm{sup -1}) under high pressure of ammonia (200 Torr) on the clean Fe(111) surface. Addition of 0.5 Torr of oxygen to 200 Torr of ammonia does not significantly change the bonding of dissociation intermediates to the surface. However, it leads to a phase change of nearly 180{sup o} between the resonant and non-resonant second order non-linear susceptibility of the surface, demonstrated by the reversal of the SFG spectral features. Heating the surface in the presence of 200 Torr ammonia and 0.5 Torr oxygen reduces the oxygen coverage, which can be seen from the SFG spectra as another relative phase change of 180{sup o}. The reduction of the oxide is also supported by Auger electron spectroscopy. The result suggests that the phase change of the spectral features could serve as a sensitive indicator of the chemical environment of the adsorbates.
Date: December 15, 2004
Creator: Westerberg, Staffan Per Gustav
Partner: UNT Libraries Government Documents Department

120 MW, 800 MHz Magnicon for a Future Muon Collider

Description: Development of a pulsed magnicon at 800 MHz was carried out for the muon collider application, based on experience with similar amplifiers in the frequency range between 915 MHz and 34.3 GHz. Numerical simulations using proven computer codes were employed for the conceptual design, while established design technologies were incorporated into the engineering design. A cohesive design for the 800 MHz magnicon amplifier was carried out, including design of a 200 MW diode electron gun, design of the magnet system, optimization of beam dynamics including space charge effects in the transient and steady-state regimes, design of the drive, gain, and output cavities including an rf choke in the beam exit aperture, analysis of parasitic oscillations and design means to eliminate them, and design of the beam collector capable of 20 kW average power operation.
Date: December 15, 2005
Creator: Hirshfield, Jay L.
Partner: UNT Libraries Government Documents Department