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Molecular Quantum Mechanics 2010: From Methylene to DNA and Beyond Conference Support

Description: This grant was $12500 for partial support of an international conference, Molecular Quantum Mechanics 2010, which was held on the campus of the University of California, Berkeley, from 24 to 29 May 2010. The conference involved more than 250 participants. The conference schedule ran from as early as 8:00 AM to as late as 10:30 PM at night, in order to accommodate six historical lectures, 16 plenary lectures, 42 invited talks and two very strong poster sessions containing 143 contributed posters. Since 1989, the Molecular Quantum Mechanics (MQM) series of international conferences has show- cased the frontiers of research in quantum chemistry with a strong focus on basic theory and algorithms, as well as highlights of topical applications. Both were strongly in evidence at MQM 2010. At the same time as embracing the future, the MQM conferences also honour the lifetime contributions of some of the most prominent scientists in the field of theoretical and computational quantum chemistry. MQM 2010 recognised the work of Prof. Henry F. ‘Fritz’ Schaefer of the Center for Computational Chemistry at the University of Georgia, who was previously on the faculty at Berkeley The travel of invited speakers was partially covered by sponsorships from Dell Computer, Hewlett-Packard, Journal of Chemical Theory and Computation, Virginia Tech College of Science, Molecular Physics, Q-Chem Inc and the American Institute of Physics. By contrast, the conference grant from the Department of Energy was used to provide fellowships and scholarships to enable graduate students and postdoctoral fellows to attend the meeting, and thereby broaden the participation of young scientists at a meeting where in the past most of the attendees have been more senior faculty researchers. We believe that we were very successful in this regard: 118 students and postdocs attended out of the total of 256 participants. In detail, ...
Date: May 15, 2013
Partner: UNT Libraries Government Documents Department

Development of Risk-Based and Technology-Independent Safety Criteria for Generation IV Systems

Description: This project has developed quantitative safety goals for Generation IV (Gen IV) nuclear energy systems. These safety goals are risk based and technology independent. The foundations for a new approach to risk analysis has been developed, along with a new operational definition of risk. This project has furthered the current state-of-the-art by developing quantitative safety goals for both Gen IV reactors and for the overall Gen IV nuclear fuel cycle. The risk analysis approach developed will quantify performance measures, characterize uncertainty, and address a more comprehensive view of safety as it relates to the overall system. Appropriate safety criteria are necessary to manage risk in a prudent and cost-effective manner. This study is also important for government agencies responsible for managing, reviewing, and for approving advanced reactor systems because they are charged with assuring the health and safety of the public.
Date: March 31, 2009
Creator: Kastenberg, William E.; Blandford, Edward & Kim, Lance
Partner: UNT Libraries Government Documents Department

A high-throughput contact-hole resolution metric for photoresists:Full-process sensitivity study

Description: The ability to accurately quantify the intrinsic resolution of chemically amplified photoresists is critical for the optimization of resists for extreme ultraviolet (EUV) Iithography. We have recently reported on two resolution metrics that have been shown to extract resolution numbers consistent with direct observation. In this paper we examine the previously reported contact-hole resolution metric and explore the sensitivity of the metric to potential error sources associated with the experimental side of the resolution extraction process. For EUV exposures at the SEMATECH Berkeley microfield exposure tool, we report a full-process error-bar in extracted resolution of 1.75 nm RMS and verify this result experimentally.
Date: January 22, 2008
Creator: Anderson, Christopher N. & Naulleau, Patrick P.
Partner: UNT Libraries Government Documents Department

Dislocation-Radiation Obstacle Interactions: Developing Improved Mechanical Property Constitutive Models

Description: Radiation damage to structural and cladding materials, including austenitic stainless steels, ferritic steels, and zirconium alloys, in nuclear reactor environments results in significant mechanical property degradation, including yield strength increases, severe ductility losses and flow localization, which impacts reliability and performance. Generation IV and advanced fuel cycle concepts under consideration will require the development of advanced structural materials, which will operate in increasingly hostile environments. The development of predictive models is required to assess the performance and response of materials in extreme Gen IV reactor operating conditions (temperature, stress, and pressure), to decrease the time to rapidly assess the properties of new materials and insert them into technological applications (Gen IV and Advanced Fuel Cycle Operations).
Date: November 29, 2007
Creator: WIrth, B.D. & Robertson, Ian M.
Partner: UNT Libraries Government Documents Department

Mn l3,2 x-ray absorption spectroscopy and magnetic circulardichroism in ferromagnetic ga1-xmnxp

Description: We have measured the X-ray absorption (XAS) and X-ray magnetic circular dichroism (XMCD) at the Mn L{sub 3,2} edges in ferromagnetic Ga{sub 1-x}Mn{sub x}P films for 0.018 {le} x {le} 0.042. Large XMCD asymmetries at the L{sub 3} edge indicate significant spin-polarization of the density of states at the Fermi energy. The spectral shapes of the XAS and XMCD are nearly identical with those for Ga{sub 1-x}Mn{sub x}As indicating that the hybridization of Mn d states and anion p states is similar in the two materials. Finally, compensation with sulfur donors not only lowers the ferromagnetic Curie temperature but also reduces the spin polarization of the hole states.
Date: July 26, 2007
Creator: Stone, P.R.; Scarpulla, M.A.; Farshchi, R.; Sharp, I.D.; Beeman,J.W.; Yu, K.M. et al.
Partner: UNT Libraries Government Documents Department

Final Report for UC Berkeley Terascale Optimal PDE Solvers TOPS DOE Award Number DE-FC02-01ER25478 9/15/2001 – 9/14/2006

Description: In many areas of science, physical experimentation may be too dangerous, too expensive or even impossible. Instead, large-scale simulations, validated by comparison with related experiments in well-understood laboratory contexts, are used by scientists to gain insight and confirmation of existing theories in such areas, without benefit of full experimental verification. The goal of the TOPS ISIC was to develop and implement algorithms and support scientific investigations performed by DOE-sponsored researchers. A major component of this effort is to provide software for large scale parallel computers capable of efficiently solving the enormous systems of equations arising from the nonlinear PDEs underlying these simulations. Several TOPS supported packages where designed in part (ScaLAPACK) or in whole (SuperLU) at Berkeley, and are widely used beyond SciDAC and DOE. Beyond continuing to develop these codes, our main effort focused on automatic performance tuning of the sparse matrix kernels (eg sparse-matrix-vector-multiply, or SpMV) at the core of many TOPS iterative solvers. Based on the observation that the fastest implementation of SpMV (and other kernels) can depend dramatically both on the computer and the matrix (the latter of which is not known until run-time), we developed and released a system called OSKI (Optimized Sparse Kernel Interface) that will automatically produce optimized version of SpMV (and other kernels), hiding complicated implementation details from the user. OSKI led to a 2x speedup in SpMV in a DOE accelerator design code, a 2x speedup in a commercial lithography simulation, and has been downloaded over 500 times. In addition to a stand-alone version, OSKI was also integrated into the TOPS-supported PETSc system.
Date: February 26, 2007
Creator: Demmel, James
Partner: UNT Libraries Government Documents Department

Physiomics Array: A Platform for Genome Research and Cultivation of Difficult-to-Cultivate Microorganisms Final Technical Report

Description: A scalable array technology for parametric control of high-throughput cell cultivations is demonstrated. The technology makes use of commercial printed circuit board (PCB) technology, integrated circuit sensors, and an electrochemical gas generation system. We present results for an array of eight 250 μl microbioreactors. Each bioreactor contains an independently addressable suite that provides closed-loop temperature control, generates feed gas electrochemically, and continuously monitors optical density. The PCB technology allows for the assembly of additional off-the-shelf components into the microbioreactor array; we demonstrate the use of a commercial ISFET chip to continuously monitor culture pH. The electrochemical dosing system provides a powerful paradigm for reproducible gas delivery to high-density arrays of microreactors. We have scaled the technology to a standard 96-well format and have constructed a system that could be easily assembled.
Date: July 10, 2006
Creator: Keasling, Jay D.
Partner: UNT Libraries Government Documents Department

A High Intensity Multi-Purpose D-D Neutron Generator for Nuclear Engineering Laboratories

Description: This NEER project involves the design, construction and testing of a low-cost high intensity D-D neutron generator for teaching nuclear engineering students in a laboratory environment without radioisotopes or a nuclear reactor. The neutron generator was designed, fabricated and tested at Lawrence Berkeley National Laboratory (LBNL).
Date: November 29, 2005
Creator: Leung, Ka-Ngo; Vujic, Jasmina L.; Morse, Edward C. & Peterson, Per F.
Partner: UNT Libraries Government Documents Department

Liquid Metal Bond for Improved Heat Transfer in LWR Fuel Rods

Description: A liquid metal (LM) consisting of 1/3 weight fraction each of Pb, Sn, and Bi has been proposed as the bonding substance in the pellet-cladding gap in place of He. The LM bond eliminates the large AT over the pre-closure gap which is characteristic of helium-bonded fuel elements. Because the LM does not wet either UO2 or Zircaloy, simply loading fuel pellets into a cladding tube containing LM at atmospheric pressure leaves unfilled regions (voids) in the bond. The HEATING 7.3 heat transfer code indicates that these void spaces lead to local fuel hot spots.
Date: August 24, 2005
Creator: Olander, Donald
Partner: UNT Libraries Government Documents Department

Anaerobic U(IV) Bio-oxidation and the Resultant Remobilization of Uranium in Contaminated Sediments

Description: A proposed strategy for the remediation of uranium (U) contaminated sites is based on immobilizing U by reducing the oxidized soluble U, U(VI), to form a reduced insoluble end product, U(IV). Due to the use of nitric acid in the processing of nuclear fuels, nitrate is often a co-contaminant found in many of the environments contaminated with uranium. Recent studies indicate that nitrate inhibits U(VI) reduction in sediment slurries. However, the mechanism responsible for the apparent inhibition of U(VI) reduction is unknown, i.e. preferential utilization of nitrate as an electron acceptor, direct biological oxidation of U(IV) coupled to nitrate reduction, and/or abiotic oxidation by intermediates of nitrate reduction. Recent studies indicates that direct biological oxidation of U(IV) coupled to nitrate reduction may exist in situ, however, to date no organisms have been identified that can grow by this metabolism. In an effort to evaluate the potential for nitrate-dependent bio-oxidation of U(IV) in anaerobic sedimentary environments, we have initiated the enumeration of nitrate-dependent U(IV) oxidizing bacteria. Sediments, soils, and groundwater from uranium (U) contaminated sites, including subsurface sediments from the NABIR Field Research Center (FRC), as well as uncontaminated sites, including subsurface sediments from the NABIR FRC and Longhorn Army Ammunition Plant, Texas, lake sediments, and agricultural field soil, sites served as the inoculum source. Enumeration of the nitrate-dependent U(IV) oxidizing microbial population in sedimentary environments by most probable number technique have revealed sedimentary microbial populations ranging from 9.3 x 101 - 2.4 x 103 cells (g sediment)-1 in both contaminated and uncontaminated sites. Interestingly uncontaminated subsurface sediments (NABIR FRC Background core FB618 and Longhorn Texas Core BH2-18) both harbored the most numerous nitrate-dependent U(IV) oxidizing population 2.4 x 103 cells (g sediment)-1. The nitrate-dependent U(IV) oxidizing microbial population in groundwaters is less numerous ranging from 0 cells mL-1 (Well FW300, ...
Date: June 1, 2005
Creator: Coates, John D.
Partner: UNT Libraries Government Documents Department

Immobilization of Radionuclides Through Anaerobic Bio-oxidation of Fe(ll)

Description: Over the last year we have focused our efforts on two independent aspects (a) further investigation of the microbiology and geochemistry of nitrate-dependent Fe(II) oxidation and (b) assembling the sequenced genome of Dechloromonas aromatica strain RCB. This work has been performed in a cooperative fashion amongst the independent labs of the three PI's with the UC Berkeley lab taking the lead under the guidance of J.D. Coates.
Date: June 1, 2005
Creator: Coates, John D.
Partner: UNT Libraries Government Documents Department

Calibration of 3D Upper Mantle Structure in Eurasia Using Regional and Teleseismic Full Waveform Seismic Data

Description: Adequate path calibrations are crucial for improving the accuracy of seismic event location and origin time, size, and mechanism, as required for CTBT monitoring. There is considerable information on structure in broadband seismograms that is currently not fully utilized. The limitations have been largely theoretical. the development and application to solid earth problems of powerful numerical techniques, such as the Spectral Element Method (SEM), has opened a new era, and theoretically, it should be possible to compute the complete predicted wavefield accurately without any restrictions on the strength or spatial extent of heterogeneity. This approach requires considerable computational power, which is currently not fully reachable in practice. We propose an approach which relies on a cascade of increasingly accurate theoretical approximations for the computation of the seismic wavefield to develop a model of regional structure for the area of Eurasia located between longitudes of 30 and 150 degrees E, and latitudes of -10 to 60 degrees North. The selected area is particularly suitable for the purpose of this experiment, as it is highly heterogeneous, presenting a challenge for calibration purposes, but it is well surrounded by earthquake sources and, even though they are sparsely distributed, a significant number of high quality broadband digital stations exist, for which data are readily accessible through IRIS (Incorporated Research Institutions for Seismology) and the FDSN (Federation of Digital Seismic Networks). The starting models used will be a combination of a-priori 3D models recently developed for this region, combining various geophysical and seismological data, and a major goal of this study will be to refine these models so as to fit a variety of seismic waveforms and phases.
Date: April 23, 2005
Creator: Romanowicz, Barbara & Panning, Mark
Partner: UNT Libraries Government Documents Department

Calibration of 3D Upper Mantle Structure in Eurasia Using Regional and Teleseismic Full Waveform Seismic Data

Description: Adequate path calibrations are crucial for improving the accuracy of seismic event location and origin time, size, and mechanism, as required for CTBT monitoring. There is considerable information on structure in broadband seismograms that is currently not fully utilized. The limitations have been largely theoretical. the development and application to solid earth problems of powerful numerical techniques, such as the Spectral Element Method (SEM), has opened a new era, and theoretically, it should be possible to compute the complete predicted wavefield accurately without any restrictions on the strength or spatial extent of heterogeneity. This approach requires considerable computational power, which is currently not fully reachable in practice. We propose an approach which relies on a cascade of increasingly accurate theoretical approximations for the computation of the seismic wavefield to develop a model of regional structure for the area of Eurasia located between longitudes of 30 and 150 degrees E, and latitudes of -10 to 60 degrees North. The selected area is particularly suitable for the purpose of this experiment, as it is highly heterogeneous, presenting a challenge for calibration purposes, but it is well surrounded by earthquake sources and, even though they are sparsely distributed, a significant number of high quality broadband digital stations exist, for which data are readily accessible through IRIS (Incorporated Research Institutions for Seismology) and the FDSN (Federation of Digital Seismic Networks). The starting models used will be a combination of a-priori 3D models recently developed for this region, combining various geophysical and seismological data, and a major goal of this study will be to refine these models so as to fit a variety of seismic waveforms and phases.
Date: April 23, 2005
Creator: Romanowicz, Barbara & Panning, Mark
Partner: UNT Libraries Government Documents Department

Calibration of 3D Upper Mantle Structure in Eurasia Using Regional and Teleseismic Full Waveform Seismic Data

Description: Adequate path calibrations are crucial for improving the accuracy of seismic event location and origin time, size, and mechanism, as required for CTBT monitoring. There is considerable information on structure in broadband seismograms that is currently not fully utilized. The limitations have been largely theoretical. the development and application to solid earth problems of powerful numerical techniques, such as the Spectral Element Method (SEM), has opened a new era, and theoretically, it should be possible to compute the complete predicted wavefield accurately without any restrictions on the strength or spatial extent of heterogeneity. This approach requires considerable computational power, which is currently not fully reachable in practice. We propose an approach which relies on a cascade of increasingly accurate theoretical approximations for the computation of the seismic wavefield to develop a model of regional structure for the area of Eurasia located between longitudes of 30 and 150 degrees E, and latitudes of -10 to 60 degrees North. The selected area is particularly suitable for the purpose of this experiment, as it is highly heterogeneous, presenting a challenge for calibration purposes, but it is well surrounded by earthquake sources and, even though they are sparsely distributed, a significant number of high quality broadband digital stations exist, for which data are readily accessible through IRIS (Incorporated Research Institutions for Seismology) and the FDSN (Federation of Digital Seismic Networks). The starting models used will be a combination of a-priori 3D models recently developed for this region, combining various geophysical and seismological data, and a major goal of this study will be to refine these models so as to fit a variety of seismic waveforms and phases.
Date: April 23, 2005
Creator: Romanowicz, Barbara & Panning, Mark
Partner: UNT Libraries Government Documents Department

Reoxidation of Bioreduced Uranium Under Reducing Conditions

Description: Stimulation of U(VI) bioreduction is becoming an attractive in-situ method for stabilizing U in contaminated sediments. After reduction of U(VI) is completed in sediments, how stable is bioreduced U(IV) upon exposure to oxidizing groundwaters?
Date: April 20, 2005
Creator: Wan, Jiamin; Tokunaga, Tetsu; Larsen, Joern; Brodie, Eoin; Wang, Zheming; Zheng, Zuoping et al.
Partner: UNT Libraries Government Documents Department

Enzyme Activity and Biomolecule Templating at Liquid and Solid Interfaces

Description: There are two main components of this research program. The first involves studies of the adsorption and catalytic activity of proteins at fluid-fluid and fluid-solid interfaces; the second employs biological macromolecules as templates at the solid-liquid interface for controlled crystallization of inorganic materials, to provide materials with specific functionality.
Date: December 1, 2004
Creator: Blanch, Harvey W.
Partner: UNT Libraries Government Documents Department

Theory of Electron Transfer in Complex Systems

Description: This research grant is the most recent of a continuous series of grants from the Department of Energy supporting our theoretical efforts to understand various electron transfer processes. In part, my research on this topic has focused on distributions of electric fields, as it is these fields that drive electron transfer. Additional focus has been concerned with kinetics, as the rates of electron transfer are central to the utility of electron transfer. Finally, we have found that the theoretical tools we originally developed to treat electron transfer can be suitably applied to understand the workings of molecular motors.
Date: October 20, 2004
Creator: Chandler, David
Partner: UNT Libraries Government Documents Department

The Advanced High-Temperature Reactor (AHTR) for Producing Hydrogen to Manufacture Liquid Fuels

Description: Conventional world oil production is expected to peak within a decade. Shortfalls in production of liquid fuels (gasoline, diesel, and jet fuel) from conventional oil sources are expected to be offset by increased production of fuels from heavy oils and tar sands that are primarily located in the Western Hemisphere (Canada, Venezuela, the United States, and Mexico). Simultaneously, there is a renewed interest in liquid fuels from biomass, such as alcohol; but, biomass production requires fertilizer. Massive quantities of hydrogen (H2) are required (1) to convert heavy oils and tar sands to liquid fuels and (2) to produce fertilizer for production of biomass that can be converted to liquid fuels. If these liquid fuels are to be used while simultaneously minimizing greenhouse emissions, nonfossil methods for the production of H2 are required. Nuclear energy can be used to produce H2. The most efficient methods to produce H2 from nuclear energy involve thermochemical cycles in which high-temperature heat (700 to 850 C) and water are converted to H2 and oxygen. The peak nuclear reactor fuel and coolant temperatures must be significantly higher than the chemical process temperatures to transport heat from the reactor core to an intermediate heat transfer loop and from the intermediate heat transfer loop to the chemical plant. The reactor temperatures required for H2 production are at the limits of practical engineering materials. A new high-temperature reactor concept is being developed for H2 and electricity production: the Advanced High-Temperature Reactor (AHTR). The fuel is a graphite-matrix, coated-particle fuel, the same type that is used in modular high-temperature gas-cooled reactors (MHTGRs). The coolant is a clean molten fluoride salt with a boiling point near 1400 C. The use of a liquid coolant, rather than helium, reduces peak reactor fuel and coolant temperatures 100 to 200 C relative to those ...
Date: October 6, 2004
Creator: Forsberg, C. W.; Peterson, P. F. & Ott, L.
Partner: UNT Libraries Government Documents Department

Development of a Methodology to Assess Proliferation Resistance and Physical Protection for Generation IV Systems

Description: Enhanced proliferation resistance and physical protection (PR&PP) is one of the technology goals for advanced nuclear concepts, such as Generation IV systems. Under the auspices of the Generation IV International Forum, the Office of Nuclear Energy, Science and Technology of the U.S. DOE, the Office of Nonproliferation Policy of the National Nuclear Security Administration, and participating organizations from six other countries are sponsoring an international working group to develop an evaluation methodology for PR&PP. This methodology will permit an objective PR&PP comparison between alternative nuclear systems (e.g., different reactor types or fuel cycles) and support design optimization to enhance robustness against proliferation, theft and sabotage. The paper summarizes the proposed assessment methodology including the assessment framework, measures used to express the PR&PP characteristics of the system, threat definition, system element and target identification, pathway identification and analysis, and estimation of the measures.
Date: October 6, 2004
Creator: Nishimura, R.; Bari, R.; Peterson, P.; Roglans-Ribas, J. & Kalenchuk, D.
Partner: UNT Libraries Government Documents Department

Combined Extraction of Cesium, Strontium, and Actinides from Alkaline Media : An Extension of the Caustic-Side Solvent Extraction (CSSX) Process Technology

Description: This fundamental research on combined cesium, strontium, and actinide separation from alkaline media by solvent extraction addresses the EM need for more efficient processes for the combined separation of these elements. The goal of this research is to obtain fundamental information for the development of more efficient processes for the combined separation of cesium, strontium, and transuranic elements from high level waste within the U.S. Department of Energy's (U.S. DOE) complex. These improved processes are targeted primarily for treating the wastes present at the U.S. DOE's Hanford and Savannah River sites. Combined separation of the radionuclides from these wastes would permit disposal of the treated waste as low-level waste, significantly reducing the volume of high level waste. Solvent extraction using the calixarene-based CSSX process has been shown to be a very effective separation method for cesium removal from High Level Waste (HLW) present at the U.S. DOE's Savannah River Site (SRS).
Date: June 1, 2004
Creator: Delmau, Laetitia H.; Hobbs, David T. & Raymond, Kenneth N.
Partner: UNT Libraries Government Documents Department

How plant functional-type, weather, seasonal drought and soil physical properties alter water and energy fluxes of an oak-grass savanna and an annual grassland.

Description: Savannas and open grasslands often co-exist in semi-arid regions. Questions that remain unanswered and are of interest to biometeorologists include: how do these contrasting landscapes affect the exchanges of energy on seasonal and annual time scales; and, do biophysical constraints imposed by water supply and water demand affect whether the land is occupied by open grasslands or savanna? To address these questions, and others, we examine how a number of abiotic, biotic and edaphic factors modulate water and energy flux densities over an oak-grass savanna and an annual grassland that coexist in the same climate but on soils with different hydraulic properties. The net radiation balance was greater over the oak woodland than the grassland, despite the fact that both canopies received similar sums of incoming short and long wave radiation. The lower albedo and lower radiative surface temperature of the transpiring woodland caused it to intercept and retain more long and shortwave energy over the course of the year, and particularly during the summer dry period. The partitioning of available energy into sensible and latent heat exchanged over the two canopies differed markedly. The annual sum of sensible heat exchange over the woodland was 40% greater than that over the grassland (2.05 GJ m{sup -2} per year versus 1.46 GJ m{sup -2} per year). With regards to evaporation, the oak woodland evaporated about 380mm of water per year and the grassland evaporated about 300mm per year. Differences in available energy, canopy roughness, the timing of physiological functioning, water holding capacity of the soil and rooting depth of the vegetation explained the observed differences in sensible and latent heat exchange of the contrasting vegetation surfaces. The response of canopy evaporation to diminishing soil moisture was quantified by comparing normalized evaporation rates (in terms of equilibrium evaporation) with soil water potential ...
Date: May 1, 2004
Creator: Baldocchi, DD, Xu L, Kiang N.
Partner: UNT Libraries Government Documents Department