A prototype equation of state (EOS) browser application has been developed at LLNL. This browser provides an interactive, graphical user interface that allows EOS data to be analyzed, visualized, and compared with experimental data. The user can view our EOS table data in both tabular and graphical form, can obtain lists of table ranges, and can view material information. In addition, the browser allows the user to utilize the interpolation routines of our EOS package to produce the same interpolated EOS data that would be passed to a simulation code, and to analyze this data in many different ways. Interpolated data can be obtained through use of a query function, and lists of interpolated data over various ranges can be produced. Analysis functions include the calculation and display of isotherms, isochores, isobars, adiabats, and shock Hugoniots. Moreover, experimental data can be overlaid onto these plots in order to establish confidence in particular EOS tables. It is expected that this browser environment will be a valuable tool for scientists who use large simulation codes that access equation of state data.

This report provides the results of a field evaluation that PNNL conducted for FEMP and the U.S. Postal Service, The report examines the performance of a sulfur lamp technology using two different light distribution systems.

This report talks about Characterization of the Damping of a Free Vibrating Piezoelectric Motor Stator by Displacement Measurements

This report is descriptive journey of the 2nd Generation PFBC Systems R&D Phase 2 AND Phase 3.

A new Lagrangian formalism for self-consistent collective neutrino-plasma interactions is presented in which each neutrino species is described as a classical ideal fluid. The neutrino-plasma fluid equations are derived from a covariant relativistic variational principle in which finite-temperature effects are retained. This new formalism is then used to investigate the generation of magnetic fields and the production of magnetic helicity as a result of collective neutrino-plasma interactions.

The purpose of the Tanks Focus Area (TFA) Midyear Review was to improve the quality and responsiveness of TFA technical solutions to identified user needs. This review goal was achieved through executing a multi-phased review approach

We have performed Monte Carlo calculations to determine the charge accumulation on threading edge dislocations in GaN as a function of the dislocation density and background dopant density. Four possible core structures have been examined, each of which produces defect levels in the gap and may therefore act as electron or hole traps. Our results indicate that charge accumulation, and the resulting electrostatic interactions, can change the relative stabilities of the different core structures. Structures having Ga and N vacancies at the dislocation core are predicted to be stable under nitrogen-rich and gallium-rich growth conditions, respectively. Due to dopant depletion at high dislocation density and the multitude of charge states, the line charge exhibits complex crossover behavior as the dopant and dislocation densities vary.

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The 12th Annual National Conference of Black Physics Students (NCBPS) was held jointly with the Annual Meeting of the National Society of Black Physicists (NSBP) March 4-8, 1998 in Lexington, Ky. The Proceedings consists of scientific talks and abstracts given by NSBP members and students attending the NCBPS meeting. One joint session of general scientific interest was held, with NCBPS students, NSBP members, and about 75 high school students from the state of Kentucky present. NCBPS session included ''How to get into Graduate School'', ''How to Survive in Graduate School'', and a Panel on ''Opportunities for Physics Graduates.'' The report by AIP: ''Survey of Participants of the 12th Annual NCBPS'' is included in the Proceedings.

This report is issued by the United States Government and talks about the advanced light source compendium of user abstracts and technical report

The primary objective of this project is to enhance domestic petroleum production by field demonstration and technology transfer of an advanced- oil-recovery technology in the Paradox basin, southeastern Utah. If this project can demonstrate technical and economic feasibility, the technique can be applied to approximately 100 additional small fields in the Paradox basin alone, and result in increased recovery of 150 to 200 million barrels (23,850,000-31,800,000 m3) of oil. This project is designed to characterize five shallow-shelf carbonate reservoirs in the Pennsylvanian (Desmoinesian) Paradox Formation and choose the best candidate for a pilot demonstration project for either a waterflood or carbon-dioxide-(CO2-) miscible flood project. The field demonstration, monitoring of field performance, and associated validation activities will take place within the Navajo Nation, San Juan County, Utah.

Understanding factors which control the long-term survival and activity of Fe(III)-reducing bacteria (FeRB) in subsurface sedimentary environments is important for predicting the ability of these organisms to serve as agents for bioremediation of organic and inorganic contaminants. This project seeks to refine our quantitative understanding of microbiological and geochemical controls on bacterial Fe(III) oxide reduction and growth of FeRB, using laboratory reactor systems which mimic to varying degrees the physical and chemical conditions of subsurface sedimentary environments. Methods for studying microbial Fe(III) oxide reduction and FeRB growth in experimental systems which incorporate advective aqueous phase flux are being developed for this purpose. These methodologies, together with an accumulating database on the kinetics of Fe(III) reduction and bacterial growth with various synthetic and natural Fe(III) oxide minerals, will be applicable to experimental and modeling studies of subsurface contaminant transformations directly coupled to or influenced by bacterial Fe(III) oxide reduction activity.

Part 2 (Basin Analysis of the Mississippi Interior Salt Basin) objectives are to provide a comprehensive analysis of the Mississippi Interior Salt Basin in Years 2 and 3 of the project and to transfer effectively the research results to producers through workshops and topical reports. Work accomplished so far: (Task 1) Tectonic History--Petroleum traps in the Mississippi Interior Salt Basin have been characterized. (Task 2) Depositional History--The depositional systems for Mesozoic strata in the Mississippi Interior Salt Basin have been identified and characterized. (Task 3) Fluid Flow--Modeling of 1-D burial and thermal history profiles for 48 wells in the Mississippi Interior Salt Basin has been completed. Multidimensional thermal maturity modeling has been initiated. (Task 4) Underdeveloped Plays--Three major exploration plays have been identified. These include the basement ridge play, the regional peripheral fault trend play, and the salt anticline play. (Task 5) Technology Transfer--No work was performed on this task for this quarter. (Task 6) Topical Reports--The topical reports on the tectonic, depositional, burial and thermal histories of the Mississippi Interior Salt Basin have been completed and sent to DOE.

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The objective of this project, which is supported by the U.S. Department of Energy (DOE) through the National Renewable Energy Laboratory (NREL), is to provide a comprehensive comparison of heavy-duty trucks operating on alternative fuels and diesel fuel. Data collection from up to eight sites is planned. Currently, the project has four sites: Raley's in Sacramento, CA (Kenworth, Cummins LlO-300G, liquefied natural gas - LNG); Pima Gro Systems, Inc. in Fontana, CA (White/GMC, Caterpillar 31768 Dual-Fuel, compressed natural gas - CNG); Waste Management in Washington, PA (Mack, Mack E7G, LNG); and United Parcel Service in Hartford, CT (Freightliner Custom Chassis, Cummins B5.9G, CNG). This paper summarizes current data collection and evaluation results from this project.

The purpose of this project was to develop tools for understanding the influence of crystal quality and crystal mounting on harmonic-generation efficiency at high irradiance. Measuring the homogeneity of crystals interferometrically, making detailed physics calculations of conversion efficiency, performing finite- element modeling of mounted crystals, and designing a new optical metrology tool were key elements in obtaining that understanding. For this work, we used the following frequency-tripling scheme: type I second- harmonic generation followed by type II sum-frequency mixing of the residual fundamental and the second harmonic light. The doubler was potassium dihydrogen phosphate (KDP), and the tripler was deuterated KDP (KD*P). With this scheme, near-infrared light (1053 nm) can be frequency tripled (to 351 nm) at high efficiency (theoretically >90%) for high irradiance (>3 GW/cm²). Spatial variations in the birefringence of the large crystals studied here (37 to 41 cm square by about 1 cm thick) imply that the ideal phase-matching orientation of the crystal with respect to the incident laser beam varies across the crystal. We have shown that phase-measuring interferometry can be used to measure these spatial variations. We observed transmitted wavefront differences between orthogonally polarized interferograms of {lambda}/50 to {lambda}/100, which correspond to index variations of …

The behavior of high temperature superconducting quantum interference devices (SQUIDs) in the presence of high temperature superconducting surfaces has been investigated. When current sources are placed close to a superconducting imaging surface (SIS) an image current is produced due to the Meissner effect. When a SQUID magnetometer is placed near such a surface it will perform in a gradiometric fashion provided the SQUID and source distances to the SIS are much less than the size of the SIS. We present the first ever experimental verification of this effect for a high temperature SIS. Results are presented for two SQUID-SIS configurations, using a 100 mm diameter YBa{sub 2}Cu{sub 3}O{sub 7-{delta}} disc as the SIS. These results indicate that when the current source and sensor coil (SQUID) are close to the SIS, the behavior is that of a first-order gradiometer. The results are compared to analytic solutions as well as the theoretical predictions of a finite element model.

Gradiometer-like devices can be built using a superconducting imaging surface design. Such devices behave similarly to conventional wire-wound gradiometers for nearby magnetic sources. A large gradiometer array can be built by placing SQUID magnetometers close to the surface of a large superconducting plane. The most attractive advantage of such a gradiometer array is the ability to change a baseline for all channels simultaneously by mechanically moving the superconducting imaging surface relative to the sensor array. This can easily be accomplished even when the gradiometer array is cold. We built, experimentally tested, and simulated both first- and second-order gradiometer-like devices with adjustable baseline using the superconducting imaging surface design. First-order radial gradiometer sensors were made by placing planar magnetometers parallel to and near the superconducting imaging surface. A second-order electronic gradiometer was realized by subtracting the output from two of the first-order gradiometers described above.

At Lawrence Livermore National Laboratory (LLNL), we are working to help calibrate the 170 seismic stations that are part of the Comprehensive Nuclear-Test-Ban Treaty (CTBT) monitoring network, in order to enhance the network's ability to locate small seismic events. These low magnitude events are likely to be recorded by only the closest of seismic stations, ranging from local to near teleseismic distances. At these distance ranges, calibration statistics become highly nonstationary, challenging us to develop more general statistical models for proper calibration. To meet the goals outlined above, we are developing a general nonstationary framework to accurately calibrate seismic travel-time predictions over the full distance range, from local, to regional, to teleseismic distances. The objective of this framework is to develop valid region-specific corrections for the Middle Fast, North Africa, and portions of the Soviet Union, to assess our progress towards meeting calibration goals, and to perform cost-benefit analysis for future calibrations. The framework integrates six core components essential to accurate calibration. First, is the compilation and statistical characterization of well located reference events, including aftershock sequences, mining explosions and rockbursts, calibration explosions, and teleseismically constrained events (Harris et al., SSA 1999; Hanley et al., SSA 1999). Second, is the …

Currently, there is interest in utilizing lignin, a major constituent of biomass, as a renewable source of chemicals and fuels. High yields of liquid products can be obtained from the flash or fast pyrolysis of biomass, but the reaction pathways that lead to product formation are not understood. To provide insight into the primary reaction pathways under process relevant conditions, we are investigating the flash vacuum pyrolysis (FVP) of lignin model compounds at 500 C. This presentation will focus on the FVP of {beta}-ether linkages containing aromatic methoxy groups and the reaction pathways of methoxy-substituted phenoxy radicals.

Solid freeform fabrication is the near-net-shape manufacturing of components by sequentially stacking thin layers of material until complicated three dimensional shapes are produced. The operation is computer controlled and requires no molds. This exciting new field of technology provides engineers with the ability to rapidly produce prototype parts directly from CAD drawings and oftentimes little or no machining is necessary after fabrication. Techniques for freeform fabrication with several types of plastics and metals are already quite advanced and maybe reviewed in references 1 and 2. Very complicated plastic models can be fabricated by stereolithography, selective laser sintering, fused deposition modeling, or three-dimensional ink jet printing. Metals may be freeformed by the LENS{trademark} technique and porous ceramic bodies by three dimensional printing into a porous powder bed. However, methods for freeform fabrication that utilize particulate slurries to build dense ceramics and composites are not as well developed. The techniques that are being developed for the freeform fabrication of dense structural ceramics primarily revolve around the sequential layering of ceramic loaded polymers or waxes. Laminated Object Manufacturing and CAM-LEM processing use controlled stacking and laser cutting of ceramic tapes [2,3]. Similar to fused deposition modeling, ceramic loaded polymer/wax filaments are being used …

This report is a summary of the work completed for an LDRD project. The objective of the project was to develop a solid freeform fabrication technique for ceramics and composites from fine particle slurries. The work was successful and resulted in the demonstration of a manufacturing technique called robocasting. Some ceramic components may pow be fabricated without the use of molds or tooling by dispensing colloidal suspensions through an orifice and stacking two-dimensional layers into three-dimensional shapes. Any conceivable two-dimensional pattern may be ''written'' layer by layer into a three-dimensional shape. Development of the robocasting technique required the materials expertise for fabrication and theological control of very highly concentrated fine particle slurries, and development of robotics for process control and optimization. Several ceramic materials have been manufactured and characterized. Development of techniques for robocasting multiple materials simultaneously have also been developed to build parts with unique structures or graded compositions.

Incorporation of nitrogen in conventional III-V compound semiconductors to form III-N-V alloys leads to a splitting of the conduction band into two nonparabolic sub-bands. The splitting can be described in terms of an anticrossing interaction between a narrow band of localized nitrogen states and the extended conduction-band states of the semiconductor matrix. The downward shift of the lower sub-band edge is responsible for the N-induced reduction of the fundamental band-gap energy. The modification of the conduction-band structure profoundly affects the optical and electrical properties of the III-N-V alloys.

Mass transport limitations impact the thermochemical processing of fossil and renewable energy resources, which involves the breakdown of cross-linked, macromolecular networks. To Investigate the molecular level details of the consequences of molecular confinement on high temperature (275-500°C) free-radical reaction pathways, we have been examining the pyrolysis of model compounds attached to the surface of non-porous silica nanoparticles through a thermally robust Si-O-C_aryl, tetha. Pyrolysis of silica-immobilized diphenylalkanes and related ethers have been studied in detail and compared with the corresponding behavior in fluid phases. The diffusional constraints can lead to reduced rates of radical termination on the surface, and enhancement of neophyl-like rearrangements, cyclization-dehydrogenation pathways, and <i>ipso-</i> aromatic substitutions. Furthermore, studies of two-component surfaces have revealed the importance of a radical relay mechanism involving rapid serial hydrogen transfer steps resulting from the molecular pre-organization on the low fractal dimension silica surface. Key findings are reviewed in this paper, and the implications of these results for fuel processing are described.