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Activation of an S6 Kinase From Human Placenta by Autophosphorylation (open access)

Activation of an S6 Kinase From Human Placenta by Autophosphorylation

Article describing a novel S6 kinase isolated from human placenta which autoactivates through autophosphorylation in vitro. The data supports the hypothesis that this previously uncharacterized S6 kinase belongs to a unique family of protein kinases which utilize autophosphorylation as part of their in vivo activation mechanism.
Date: September 15, 1993
Creator: Dennis, Patrick B. & Masaracchia, Ruthann A.
System: The UNT Digital Library
Incorporation of excess weapons material into the IFR fuel cycle (open access)

Incorporation of excess weapons material into the IFR fuel cycle

The Integral Fast Reactor (IFR) provides both a diversion resistant closed fuel cycle for commercial power generation and a means of addressing safeguards concerns related to excess nuclear weapons material. Little head-end processing and handling of dismantled warhead materials is required to convert excess weapons plutonium (Pu) to IFR fuel and a modest degree of proliferation protection is available immediately by alloying weapons Pu to an IFR fuel composition. Denaturing similar to that of spent fuel is obtained by short cycle (e.g. 45 day) use in an IFR reactor, by mixing which IFR recycle fuel, or by alloying with other spent fuel constituents. Any of these permanent denaturings could be implemented as soon as an operating IFR and/or an IFR recycle capability of reasonable scale is available. The initial Pu charge generated from weapons excess Pu can then be used as a permanent denatured catalyst, enabling the IFR to efficiently and economically generate power with only a natural or depleted uranium feed. The Pu is thereafter permanently safeguarded until consumed, with essentially none going to a waste repository.
Date: September 1, 1993
Creator: Hannum, W. H. & Wade, D. C.
System: The UNT Digital Library
Simulation and analysis of rf feedback systems on the SLC damping rings (open access)

Simulation and analysis of rf feedback systems on the SLC damping rings

The rf system of the SLC Damping Rings has evolved since tighter tolerances on beam stability are encountered as beam intensities are increased. There are now many feedback systems controlling the phase and amplitude of the rf, the phase of the beam, and the tune of the cavity. The bandwidths of the feedback loops range from several MHz to compensate for beam loading to a few Hz for the cavity tuners. To improve our understanding of the interaction of these loops and verify the expected behavior, we have simulated their behavior using computer models. A description of the models and the first results are discussed.
Date: September 1, 1993
Creator: Minty, M.; Himel, T.; Krejcik, P.; Siemann, R. H. & Tighe, R.
System: The UNT Digital Library
Local structure and superconductivity in La{sub 2-x}Ba{sub x}CuO{sub 4} for x=0.125 and x=0.15 (open access)

Local structure and superconductivity in La{sub 2-x}Ba{sub x}CuO{sub 4} for x=0.125 and x=0.15

This paper reviews our recent work on characterising the structural and electronic transitions in La{sub 2-x}Ba{sub x}CuO{sub 4}. This is a high-temperature superconductor which shows interesting an interesting interrelationship between structure and atomic properties. We have used x-ray and neutron diffraction to characterize the structure and show tat the current understanding of the structural phase transitions, and their relationship to the superconductivity, is incomplete.
Date: September 1, 1993
Creator: Billinge, S. J. L.; Kwei, G. H. & Takagi, H.
System: The UNT Digital Library
Contaminated scrap metal management on the Oak Ridge Reservation (open access)

Contaminated scrap metal management on the Oak Ridge Reservation

Large quantities of scrap metal are accumulating at the various Department of Energy (DOE) installations across the country as a result of ongoing DOE programs and missions in concert with present day waste management practices. DOE Oak Ridge alone is presently storing around 500,000 tons of scrap metal. The local generation rate, currently estimated at 1,400 tons/yr, is expected to increase sharply over the next couple of years as numerous environmental restoration and decommissioning programs gain momentum. Projections show that 775,000 tons of scrap metal could be generated at the K-25 Site over the next ten years. The Y-12 Plant and Oak Ridge National Laboratory (ORNL) have similar potentials. The history of scrap metal management at Oak Ridge and future challenges and opportunities are discussed.
Date: September 1, 1993
Creator: Hayden, H. W.; Stephenson, M. J.; Bailey, J. K.; Weir, J. R. & Gilbert, W. C.
System: The UNT Digital Library
The Epicure Control System (open access)

The Epicure Control System

The Epicure Control System supports the Fermilab fixed target physics program. The system is distributed across a network of many different types of components. The use of multiple layers on interfaces for communication between logical tasks fits the client-server model. Physical devices are read and controlled using symbolic references entered into a database with an editor utility. The database system consists of a central portion containing all device information and optimized portions distributed among many nodes. Updates to the database are available throughout the system within minutes after being requested.
Date: September 1, 1993
Creator: Dambik, E.; Kline, D. & West, R.
System: The UNT Digital Library
Plasma-chemical conversion of hydrogen sulfide into hydrogen and sulfur (open access)

Plasma-chemical conversion of hydrogen sulfide into hydrogen and sulfur

A waste-treatment process that recovers both hydrogen and sulfur from hydrogen-sulfide-contaminated industrial wastes is being developed to replace the Claus technology, which recovers only sulfur. The proposed process is based on research reported in the Soviet technical literature and uses microwave (or radio-frequency) energy to initiate plasma-chemical reactions that dissociate hydrogen sulfide into elemental hydrogen and sulfur. In the plasma-chemical process, the gaseous stream would be purified and separated into streams containing the product hydrogen, hydrogen sulfide for recycle to the plasma reactor, and the process purge containing carbon dioxide and water. Since unconverted hydrogen sulfide is recycled to the plasma reactor, the plasma-chemical process has the potential for sulfur recoveries in excess of 99% without the additional tail-gas clean-up processes associated with the Claus technology. Laboratory experiments with pure hydrogen sulfide have confirmed that conversions of over 90% per pass are possible. Experiments with impurities typical of petroleum refinery and natural gas production acid gases have demonstrated that these impurities are compatible with the plasma dissociation process and do not appear to create new waste-treatment problems. Other experiments show that the cyclonic-flow pattern hypothesized by the Russian theoretical analysis of the plasma-chemical process can substantially decrease energy requirements for …
Date: September 1, 1993
Creator: Harkness, J. B. L.; Doctor, R. D. & Daniels, E. J.
System: The UNT Digital Library
Thermal/chemical degradation of inorganic membrane materials (open access)

Thermal/chemical degradation of inorganic membrane materials

The specific objectives of this program are to (1) identify and evaluate long-term degradation mechanisms for inorganic membranes exposed to hot coal gasification and combustion gas streams using data from the existing literature, (2) quantify the extent of the degradation process for the most serious mechanisms by performing experiments under laboratory-scale conditions, and (3) develop a predictive model that allows estimation of membrane degradation under operating conditions. To achieve the above objectives, the program is divided into the following tasks: (1) Development of evaluation methodology; (2) evaluation of potential long-term degradation mechanism; (3) submission of a topical report and a plan for experimental testing; (4) experimental testing; and (5) model development. Tasks 4 and 5 are separate options that may be exercised by the US Department of Energy at the conclusion of Task 3. Accomplishments are presented for Tasks 1, 2 and 3.
Date: September 1, 1993
Creator: Krishnan, G. N.; Sanjurgo, A. & Wood, B. J.
System: The UNT Digital Library
Effect of powder characteristics on gas-pressure sintering of Si{sub 3}N{sub 4} with rare earth additives (open access)

Effect of powder characteristics on gas-pressure sintering of Si{sub 3}N{sub 4} with rare earth additives

Several Si{sub 3}N{sub 4} powders, synthesized by various methods and having different surface areas, oxygen contents and impurity levels, were examined. During early stage densification, all powders showed similar shrinkage with the diimide ederived powder exhibiting delayed {alpha}/{beta} transformation compared to the other powders. The diimide and gas-phase derived powders achieved the highest final densities. Improved densification was observed by increasing the oxygen content and this also resulted in high toughness for some materials with rare earth apatite additives. However, the increased oxygen resulted in reduced high temperature strength. Fracture toughnesses (K{sub Ic}) up to 10 MPa{radical}m were obtained for some compositions.
Date: September 1, 1993
Creator: Tiegs, T. N.; Nunn, S. D.; Walls, C. A.; Barker, D.; Davisson, C. & Jones, P. J.
System: The UNT Digital Library
RHIC Beam Position Monitor Assemblies (open access)

RHIC Beam Position Monitor Assemblies

Design calculations, design details, and fabrication techniques for the RHIC BPM Assemblies are discussed. The 69 mm aperture single plane detectors are 23 cm long short-circuited 50 ohm strip transmission lines subtending 80 degrees. They are mounted on the sextupole end of the Corrector-Quadrupole-Sextupole package and operate at liquid helium temperature. The 69 cm aperture was selected to be the same as that of the beampipe in the CQS package, dc 23 cm length is a compromise between mechanical stability and electrical sensitivity to the long low-intensity proton and heavy ion bunches to be found in RHIC during commissioning, and the 80 degree subtended angle maximizes linear aperture. The striplines are aligned after brazing to maintain electrical-to-mechanical centers within 0.1 mm radius, eliminating the need for individual calibration. Because the cryogenic feedthrus isolate the UHV beam vacuum only from the HV insulating vacuum, and do not see liquid helium, a replaceable mini-ConFlat design was chosen to simplify fabrication, calibration, and maintenance.
Date: September 1, 1993
Creator: Cameron, P. R.; Grau, M. C.; Ryan, W. A.; Shea, T. J. & Sikora, R. E.
System: The UNT Digital Library
Radionuclide separations for the reduction of high-level waste volume (open access)

Radionuclide separations for the reduction of high-level waste volume

None
Date: September 1, 1993
Creator: Lumetta, G. J.; Swanson, J. L. & Bray, L. A.
System: The UNT Digital Library
Threat of a sinkhole: A reevaluation of Cavern 4, Bayou Choctaw salt dome, Louisiana (open access)

Threat of a sinkhole: A reevaluation of Cavern 4, Bayou Choctaw salt dome, Louisiana

Cavern Lake at Bayou Choctaw salt dome resulted from the failure of Cavern 7 in 1954. Uncontrolled solutioning of this cavern through the thin caprock had set the stage for overburden to collapse into the cavern below. A similar situation developed with nearby Cavern 4, but with less dissolutioning of the caprock. Because pressure loss was already a problem and because another 800 ft diameter lake would have endangered surface operations, solutioning of Cavern 4 was stopped and the cavern abandoned in 1957 in order to protect the already-small site. In 1978 the Strategic Petroleum Reserve (SPR) acquired a number of caverns at Bayou Choctaw, including Cavern 4, and the possible repeat of the Cavern 7 failure and formation of another lake thus became an issue. The cavern dimensions were re-sonared in 1980 for comparison with 1963 and 1977 surveys. Annual surface leveling between 1982--1992 showed less subsidence occurring than the site average, and a cavern monitoring system, installed in 1984, has revealed no anomalous motion. Repeat sonar surveys in 1992 showed very little, if any, change occurred since 1980 although a small amount of uncertainty exists as a result of changing sonar techniques. We conclude that significant additional solutioning …
Date: September 1, 1993
Creator: Neal, J. T.; Todd, J. L.; Linn, J. K. & Magorian, T. R.
System: The UNT Digital Library
Magnetic insulation of secondary electrons in plasma source ion implantation (open access)

Magnetic insulation of secondary electrons in plasma source ion implantation

The uncontrolled loss of accelerated secondary electrons in plasma source ion implantation (PSII) can significantly reduce system efficiency and poses a potential x-ray hazard. This loss might be reduced by a magnetic field applied near the workpiece. The concept of magnetically-insulated PSII is proposed, in which secondary electrons are trapped to form a virtual cathode layer near the workpiece surface where the local electric field is essentially eliminated. Subsequent electrons that are emitted can then be reabsorbed by the workpiece. Estimates of anomalous electron transport from microinstabilities are made. Insight into the process is gained with multi-dimensional particle-in-cell simulations.
Date: September 1, 1993
Creator: Rej, D. J.; Wood, B. P.; Faehl, R. J. & Fleischmann, H. H.
System: The UNT Digital Library
Data uncertainty impact in radiotoxicity evaluation connected to EFR and IRF systems (open access)

Data uncertainty impact in radiotoxicity evaluation connected to EFR and IRF systems

Time-dependent sensitivity techniques, which have been used in the past for standard reactor applications, have been adapted to calculate the impact of data uncertainties in radiotoxicity evaluations. The methodology has been applied to different strategies of radioactive waste management connected with the EFR and IFR reactor fuel cycles. Results are provided in terms of sensitivity coefficients to basic data (cross sections and decay constants), and uncertainties on global radiotoxicity at different times of storing after discharge.
Date: September 1, 1993
Creator: Palmiotti, G.; Salvatores, M. & Hill, R. N.
System: The UNT Digital Library
Benchmarking UEDGE with DIII-D data (open access)

Benchmarking UEDGE with DIII-D data

Comparisons between a 2-D fluid simulation of the scrape-off-layer (SOL) plasma of a diverted tokamak and experimental data from the DIII-D are shown. It is concluded that a simple diffusive model for perpendicular transport is consistent with the data. Discrepancies in the simulation suggest that impurity radiation may be playing a significant role in the experiment, and that further work is required to understand hydrogen recycling at the divertor.
Date: September 1, 1993
Creator: Porter, G. D.; Fenstermacher, M.; Rensink, M. E.; Rognlien, T. D.; Groebner, R.; Leonard, A. et al.
System: The UNT Digital Library
Characterization studies of lower and non-TDI polyurethane encapsulants (open access)

Characterization studies of lower and non-TDI polyurethane encapsulants

Polyurethane prepolymers containing toluene diisocyanate (TDI) are used within the Nuclear Weapons complex for many adhesive and encapsulation applications. As part of a program for minimizing hazards to workers and the environment, TDI will be eliminated. This report presents evaluation of alternative encapsulants.
Date: September 1, 1993
Creator: Wilson, M. H.
System: The UNT Digital Library
Coal Ash Behavior in Reducing Environments (open access)

Coal Ash Behavior in Reducing Environments

A series of tests have been conducted on two coals with the PDTF under various conditions (temperatures ranging from 1100{degree} to 1500{degree}C, pressures ranging from 50 to 100 psi, O/C ratios ranging from 1.0 to 2.0, and residence times ranging from 5 to 13 seconds). In summary, the results from the pressurized drop-tube furnace testing show differences in the inorganic transformations as a function of temperature residence time and coal type. The gas atmosphere and pressure did not have a visibly substantial effect on the results. It is expected that in a full-scale system that is oxygen- and/or air-blown, the initial atmosphere that the particles see will be similar regardless of amount of oxygen/air, but during the later stages the gas compositions will be significantly different. This would impact the vapor species, such as sodium, the most. The formation of calcium sulfide appears limited by high temperatures and longer residence times. This is primarily due to the instability of calcium sulfide at high temperatures. Iron sulfide, formed form the pyrite content in the coal, has a kinetically limited life in the high temperature regions of a gasification reactor. The iron sulfide decomposes to form metallic iron and iron aluminosilicates. The …
Date: September 1, 1993
Creator: Benson, S. A.; Erickson, T. A.; Brekke, D. W.; Folkedahl, B. C.; Tibbetts, J. E. & Nowok, J. W.
System: The UNT Digital Library
Hazardous waste cleanup at federal facilities: Need for an integrated policy (open access)

Hazardous waste cleanup at federal facilities: Need for an integrated policy

The U.S. Department of Energy (DOE) has generated and disposed of large volumes of hazardous and radioactive waste as a result of 50 years of nuclear weapons production. DOE is now faced with the problem of remediating its more than 13,000 hazardous waste sites. To be effective for the good of the environment and public health, our nation`s hazardous waste policy must first address several questions: What is the level of risk at federal facilities? (Is remediation really necessary?) Can and should institutional controls be incorporated into the cleanup process? How effective are cleanup technologies? What cleanup standards should be used? What will be done with waste generated during remediation? How do we obtain appropriate stakeholder involvement? Once these questions are answered and a more reliable, predictable policy has been developed, the waste management and environmental restoration program may not be an unwanted drain on America`s pocketbook, and we may have a cleaner country as well.
Date: September 22, 1993
Creator: Travis, C. C. & Ladd, B.
System: The UNT Digital Library
Fact-based Enterprise Information Management using NIAM (open access)

Fact-based Enterprise Information Management using NIAM

The effort to consolidate the ``islands of information`` within an enterprise -- to manage information at the enterprise level rather than the department or sub-system level -- is known by many names, such as ``Information Resource Management`` and ``Corporate Data Administration``. Here we will call it ``Enterprise Information Management`` (EIM). This effort is becoming increasingly vital as the need for shared information grows, yet it is plagued by costly, time-consuming efforts that produce reams of hard-to-maintain documentation. The results are difficult to integrate, measure, or apply. Management needs a tool that can integrate models from diverse modeling efforts into a global knowledge base, produce metrics to clarify the value of the integration process, and provide a short, traceable route between information models and their physical implementations. The natural-language emphasis of NIAM makes it an ideal candidate for this tool. When integrated with enterprise-wide data administration, the collection of metrics, CASE tools that produce application code, and automated support tools, NIAM can effectively manage multiple Universes of Discourse (UOD). Prototypes of automated support tools, ``Fact Manager`` and ``Fact Designer``, will be discussed.
Date: September 1, 1993
Creator: Rivord, G.
System: The UNT Digital Library
Pions and neutrinos as probes of the nucleon and nuclear few-body system (open access)

Pions and neutrinos as probes of the nucleon and nuclear few-body system

A number of studies of few-body nucleon and nuclear systems are being pursued at LAMPF using pions and neutrinos as probes. These include: a high-statistics measurement of the cross section for the reaction {pi}{sup +}p {yields} {pi}{sup +}{pi}{sub o}{pi}{sup 0} to determine the 1 = 2 {pi}{pi} scattering length; precision measurements of the {pi}{sup {minus}}p charge exchange cross section in the region of the A; measurements of the cross section for the ({pi}{sup +}p {yields} {pi}{sup +}{pi}{sup +} p), from D, {sup 3}He as {sup 4}He as tests of charge symmetry and reaction mechanisms; measurements of the {pi}{sup +}p cross section below the {Delta}; and studies of vp elastic scattering at low Q{sup 2} to determine the quark content of the proton spin. Some of these experiments acquired data last year, while others are presently running. LAMPF, the highest power proton accelerator in the world, is presently in the midst of its 1993 production run.
Date: September 1, 1993
Creator: Hoffman, C. M.
System: The UNT Digital Library
Molten carbonate fuel cell networks: Principles, analysis and performance (open access)

Molten carbonate fuel cell networks: Principles, analysis and performance

Key to the concept of networking is multiple fuel cell stacks with regard to flow of reactant streams. In a fuel cell network, reactant streams are ducted so that they are fed and recycled through stacks in series. Stacks networked in series more closely approach a reversible process, which increases efficiency. Higher total reactant utilizations can be achieved by stacks networked in series. Placing stacks in series also allows reactant streams to be conditioned at different stages of utilization. Between stacks, heat can be consumed or removed, (methane injection, heat exchange) which improves thermal balance. Composition of streams can be adjusted between stacks by mixing exhaust streams or by injecting reactant streams. Computer simulations demonstrated that a combined cycle system with MCFC stacks networked in series is more efficient than an identical system with MCFC stacks in parallel.
Date: September 1, 1993
Creator: Wimer, J. G.; Williams, M. C.; Archer, D. H. & Osterle, J. F.
System: The UNT Digital Library
LASH oxidation, waste management (open access)

LASH oxidation, waste management

Temperature for highest sulfation of both as-received KRW LASH and FW LASH was found to be 1700{degrees}F in the temperature range of 1500 to 1700{degrees}F studied. No significant amount of SO{sub 2} was measured by gas analysis in the tests reported here. Confirmation of SO{sub 2} release by sulfur balance including the solids is in progress. The sulfide conversion achieved for HSCF KRW LASH including the conversion obtained in the muffle furnace was about 80%. Grinding it did not enhance the conversion. By grinding and then doping it with an alkali, the conversion was increased to about 95%. The impregnation of CFHS FW LASH with the alkali enhanced the sulfide conversion to a high level (94%) just as observed for HSCF KRW LASH. The absorption of H{sub 2}S by the KRW LASH is as good as that observed for the two pure limestones used in this study. The absorption of SO{sub 2} by the KRW LASH is poor compared to that of the pure limestones. Additional experiments are planned to attempt to identify the mechanism.
Date: September 1, 1993
Creator: Shires, P. J.; Katta, S. & Henningsen, G.
System: The UNT Digital Library
The systems and the developmental target for IGCC (open access)

The systems and the developmental target for IGCC

Brief descriptions are provided concerning integrated combined cycle power technology and fluidized bed combustion technology. The General Electric Integrated Gasifier and HGCU Operation program, Power Systems Development Facility, Gasification Product Improvement Facility, and Advanced Gas Turbine Systems Program are discussed.
Date: September 1, 1993
Creator: Schmidt, D. K.
System: The UNT Digital Library
Applications of the Aurora parallel Prolog system to computational molecular biology (open access)

Applications of the Aurora parallel Prolog system to computational molecular biology

We describe an investigation into the use of the Aurora parallel Prolog system in two applications within the area of computational molecular biology. The computational requirements were large, due to the nature of the applications, and were large, due to the nature of the applications, and were carried out on a scalable parallel computer the BBN ``Butterfly`` TC-2000. Results include both a demonstration that logic programming can be effective in the context of demanding applications on large-scale parallel machines, and some insights into parallel programming in Prolog.
Date: September 1, 1993
Creator: Lusk, E. L.; Overbeek, R.; Mudambi, S. & Szeredi, P.
System: The UNT Digital Library