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High-performance combinatorial algorithms

Description: Combinatorial algorithms have long played an important role in many applications of scientific computing such as sparse matrix computations and parallel computing. The growing importance of combinatorial algorithms in emerging applications like computational biology and scientific data mining calls for development of a high performance library for combinatorial algorithms. Building such a library requires a new structure for combinatorial algorithms research that enables fast implementation of new algorithms. We propose a structure for combinatorial algorithms research that mimics the research structure of numerical algorithms. Numerical algorithms research is nicely complemented with high performance libraries, and this can be attributed to the fact that there are only a small number of fundamental problems that underlie numerical solvers. Furthermore there are only a handful of kernels that enable implementation of algorithms for these fundamental problems. Building a similar structure for combinatorial algorithms will enable efficient implementations for existing algorithms and fast implementation of new algorithms. Our results will promote utilization of combinatorial techniques and will impact research in many scientific computing applications, some of which are listed.
Date: October 31, 2003
Creator: Pinar, Ali
Partner: UNT Libraries Government Documents Department

Comparison of three options for geologic sequestration of CO2 - a case study for California

Description: Options for sequestration of CO{sub 2} are best viewed in light of the regional distribution of CO{sub 2} sources and potential sequestration sites. This study examines the distribution of carbon emissions from fossil fuel power plants in California and their proximity to three types of reservoirs that may be suitable for sequestration: (1) active or depleted oil fields, (2) active or depleted gas fields, and (3) brine formations. This paper also presents a preliminary assessment of the feasibility of sequestering CO{sub 2} generated from large fossil-fuel fired power plants in California and discusses the comparative advantages of three different types of reservoirs for this purpose. Based on a volumetric analysis of sequestration capacity and current CO{sub 2} emission rates from oil/gas fired power plants, this analysis suggests that oil reservoirs, gas fields and brine formations can all contribute significantly to sequestration in California. Together they could offer the opportunity to meet both short and long term needs. In the near term, oil and gas reservoirs are the most promising because the trapping structures have already stood the test of time and opportunities for offsetting the cost of sequestration with revenues from enhanced oil and gas production. In the long term, if the trapping mechanisms are adequately understood and deemed adequate, brine formations may provide an even larger capacity for geologic sequestration over much of California.
Date: September 1, 2000
Creator: Benson, S.M.
Partner: UNT Libraries Government Documents Department

Development of high-intensity D-D and D-T neutron sources and neutron filters for medical and industrial applications

Description: This thesis consists of three main parts. The first one relates to boron neutron capture therapy. It summarizes the guidelines obtained by numerical simulations for the treatment of shallow and deep-seated brain tumors, as well as the results on the design of beam-shaping assemblies to moderate D-D and D-T neutrons to epithermal energies. The second part is about boron neutron capture synovectomy for the treatment of rheumatoid arthritis. Optimal neutron energy for treatment and beam-shaping assembly designs are summarized in this section. The last part is on the development of the sealed neutron generator, including experimental results on the prototype ion source and the prototype accelerator column.
Date: May 10, 2000
Creator: Verbeke, J.M.
Partner: UNT Libraries Government Documents Department

Electron-impact ionization of atomic hydrogen

Description: Since the invention of quantum mechanics, even the simplest example of collisional breakup in a system of charged particles, e{sup {minus}} + H {r_arrow} H{sup +} + e{sup {minus}} + e{sup {minus}}, has stood as one of the last unsolved fundamental problems in atomic physics. A complete solution requires calculating the energies and directions for a final state in which three charged particles are moving apart. Advances in the formal description of three-body breakup have yet to lead to a viable computational method. Traditional approaches, based on two-body formalisms, have been unable to produce differential cross sections for the three-body final state. Now, by using a mathematical transformation of the Schrodinger equation that makes the final state tractable, a complete solution has finally been achieved, Under this transformation, the scattering wave function can be calculated without imposing explicit scattering boundary conditions. This approach has produced the first triple differential cross sections that agree on an absolute scale with experiment as well as the first ab initio calculations of the single differential cross section.
Date: February 14, 2000
Creator: Baertschy, Mark D.
Partner: UNT Libraries Government Documents Department

Pump probe spectroscopy of quasiparticle dynamics in cuprate superconductors

Description: Pump probe spectroscopy is used to examine the picosecond response of a BSCCO thin film, and two YBCO crystals in the near infrared. The role of pump fluence and temperature have been closely examined in an effort to clarify the mechanism by which the quasiparticles rejoin the condensate. BSCCO results suggest that the recombination behavior is consistent with the d-wave density of states in that quasiparticles appear to relax to the nodes immediately before they rejoin the condensate. The first substantial investigation of polarized pump probe response in detwinned YBCO crystals is also reported. Dramatic doping dependent anisotropies along the a and b axes are observed in time and temperature resolved studies. Among many results, we highlight the discovery of an anomalous temperature and time dependence of a- axis response in optimally doped YBCO. We also report on the first observation of the photoinduced response in a magnetic field. We find the amplitude of the response, and in some cases, the dynamics considerably changed with the application of a 6T field. Finally, we speculate on two of the many theoretical directions stimulated by our results. We find that the two-fluid model suggests a mechanism to explain how changes at very low energies are visible to a high-energy probe. Also discussed are basic recombination processes which may play a role in the observed decay.
Date: May 1, 2001
Creator: Segre, Gino P.
Partner: UNT Libraries Government Documents Department

Towards a precision measurement of theta13 with reactor neutrinos: Initiatives in the United States

Description: Recent experimental results have provided unambiguous evidence that neutrinos have a small but finite mass and mix from one type into another. The phenomenon of neutrino mixing is characterized by the coupling between the neutrino flavor (nu e,mu,tau) and mass eigenstates (nu 1,2,3) and the associated mixing angles. Previous neutrino oscillation experiments have determined two of the three mixing angles in the neutrino mixing matrix, U MNSP. Using multiple neutrino detectors placed at different distances from a nuclear power plant, a future reactor neutrino experiment has the potential to discover and measure the coupling of the electron neutrino flavor to the third mass eigenstate, Ue3, the last undetermined element of the neutrino mixing matrix. In this paper we describe recent efforts in the US towards a next-generation experiment to measure theta13 with reactor neutrinos.
Date: September 12, 2004
Creator: Heeger, Karsten M.
Partner: UNT Libraries Government Documents Department

T2LBM Version 1.0: Landfill bioreactor model for TOUGH2

Description: The need to control gas and leachate production and minimize refuse volume in landfills has motivated the development of landfill simulation models that can be used by operators to predict and design optimal treatment processes. T2LBM is a module for the TOUGH2 simulator that implements a Landfill Bioreactor Model to provide simulation capability for the processes of aerobic or anaerobic biodegradation of municipal solid waste and the associated flow and transport of gas and liquid through the refuse mass. T2LBM incorporates a Monod kinetic rate law for the biodegradation of acetic acid in the aqueous phase by either aerobic or anaerobic microbes as controlled by the local oxygen concentration. Acetic acid is considered a proxy for all biodegradable substrates in the refuse. Aerobic and anaerobic microbes are assumed to be immobile and not limited by nutrients in their growth. Methane and carbon dioxide generation due to biodegradation with corresponding thermal effects are modeled. The numerous parameters needed to specify biodegradation are input by the user in the SELEC block of the TOUGH2 input file. Test problems show that good matches to laboratory experiments of biodegradation can be obtained. A landfill test problem demonstrates the capabilities of T2LBM for a hypothetical two-dimensional landfill scenario with permeability heterogeneity and compaction.
Date: May 22, 2001
Creator: Oldenburg, Curtis M.
Partner: UNT Libraries Government Documents Department

Mineral dissolution kinetics at the pore scale

Description: Mineral dissolution rates in the field have been reported to be orders of magnitude slower than those measured in the laboratory, an unresolved discrepancy that severely limits our ability to develop scientifically defensible predictive or even interpretive models for many geochemical processes in the earth and environmental sciences. One suggestion links this discrepancy to the role of physical and chemical heterogeneities typically found in subsurface soils and aquifers in producing scale-dependent rates where concentration gradients develop. In this paper, we examine the possibility that scale-dependent mineral dissolution rates can develop even at the single pore and fracture scale, the smallest and most fundamental building block of porous media. To do so, we develop two models to analyze mineral dissolution kinetics at the single pore scale: (1) a Poiseuille Flow model that applies laboratory-measured dissolution kinetics at the pore or fracture wall and couples this to a rigorous treatment of both advective and diffusive transport, and (2) a Well-Mixed Reactor model that assumes complete mixing within the pore, while maintaining the same reactive surface area, average flow rate, and geometry as the Poiseuille Flow model. For a fracture, a 1D Plug Flow Reactor model is considered in addition to quantify the effects of longitudinal versus transverse mixing. The comparison of averaged dissolution rates under various conditions of flow, pore size, and fracture length from the three models is used as a means to quantify the extent to which concentration gradients at the single pore and fracture scale can develop and render rates scale-dependent. Three important minerals that dissolve at widely different rates, calcite, plagioclase, and iron hydroxide, are considered. The modeling indicates that rate discrepancies arise primarily where concentration gradients develop due to comparable rates of reaction and advective transport, and incomplete mixing via molecular diffusion. The magnitude of the reaction ...
Date: May 24, 2007
Creator: Li, L.; Steefel, C.I. & Yang, L.
Partner: UNT Libraries Government Documents Department

Effect of sorption on exposures to organic gases from environmental tobacco smoke (ETS)

Description: The effects of sorption processes on dynamic ETS organic gas concentrations and potential exposures were studied in a carpeted and furnished 50-m{sup 3} room ventilated at 0.6 h{sup -1}. Ten cigarettes were machine-smoked on six of every seven days over four weeks. Concentrations of ETS-specific tracers and regulated toxic compounds were quantified during daily smoking, post-smoking and background periods. Potential exposures were calculated by period and day. Large sorption effects were observed for the widely used tracers 3-ethenylpyridine and nicotine, and for several toxic compounds including naphthalene and cresol isomers. Short-term adsorption to indoor surfaces reduced concentrations and potential exposures during smoking, while later reemission increased concentrations and exposures hours after smoking ended. Concentrations during nonsmoking periods rose from day to day over the first few weeks, presumably from increased reemission associated with increased sorbed mass concentrations. For sorbing compounds, more than half of daily potential exposures occurred during nonsmoking periods.
Date: January 1, 2002
Creator: Singer, B.C.; Hodgson, A.T. & Nazaroff, W.W.
Partner: UNT Libraries Government Documents Department

Network Characterization Service (NCS)

Description: Distributed applications require information to effectively utilize the network. Some of the information they require is the current and maximum bandwidth, current and minimum latency, bottlenecks, burst frequency, and congestion extent. This type of information allows applications to determine parameters like optimal TCP buffer size. In this paper, we present a cooperative information-gathering tool called the network characterization service (NCS). NCS runs in user space and is used to acquire network information. Its protocol is designed for scalable and distributed deployment, similar to DNS. Its algorithms provide efficient, speedy and accurate detection of bottlenecks, especially dynamic bottlenecks. On current and future networks, dynamic bottlenecks do and will affect network performance dramatically.
Date: June 6, 2001
Creator: Jin, Guojun; Yang, George; Crowley, Brian & Agarwal, Deborah
Partner: UNT Libraries Government Documents Department

Network Characterization Service (NCS)

Description: Distributed applications require information to effectively utilize the network. Some of the information they require is the current and maximum bandwidth, current and minimum latency, bottlenecks, burst frequency, and congestion extent. This type of information allows applications to determine parameters like optimal TCP buffer size. In this paper, we present a cooperative information-gathering tool called the network characterization service (NCS). NCS runs in user space and is used to acquire network information. Its protocol is designed for scalable and distributed deployment, similar to DNS. Its algorithms provide efficient, speedy and accurate detection of bottlenecks, especially dynamic bottlenecks. On current and future networks, dynamic bottlenecks do and will affect network performance dramatically.
Date: June 6, 2001
Creator: Jin, Guojun; Yang, George; Crowley, Brian & Agarwal, Deborah
Partner: UNT Libraries Government Documents Department

Application of parallel computing techniques to a large-scale reservoir simulation

Description: Even with the continual advances made in both computational algorithms and computer hardware used in reservoir modeling studies, large-scale simulation of fluid and heat flow in heterogeneous reservoirs remains a challenge. The problem commonly arises from intensive computational requirement for detailed modeling investigations of real-world reservoirs. This paper presents the application of a massive parallel-computing version of the TOUGH2 code developed for performing large-scale field simulations. As an application example, the parallelized TOUGH2 code is applied to develop a three-dimensional unsaturated-zone numerical model simulating flow of moisture, gas, and heat in the unsaturated zone of Yucca Mountain, Nevada, a potential repository for high-level radioactive waste. The modeling approach employs refined spatial discretization to represent the heterogeneous fractured tuffs of the system, using more than a million 3-D gridblocks. The problem of two-phase flow and heat transfer within the model domain leads to a total of 3,226,566 linear equations to be solved per Newton iteration. The simulation is conducted on a Cray T3E-900, a distributed-memory massively parallel computer. Simulation results indicate that the parallel computing technique, as implemented in the TOUGH2 code, is very efficient. The reliability and accuracy of the model results have been demonstrated by comparing them to those of small-scale (coarse-grid) models. These comparisons show that simulation results obtained with the refined grid provide more detailed predictions of the future flow conditions at the site, aiding in the assessment of proposed repository performance.
Date: February 1, 2001
Creator: Zhang, Keni; Wu, Yu-Shu; Ding, Chris & Pruess, Karsten
Partner: UNT Libraries Government Documents Department

Multiphase Modeling of Flow, Transport, and Biodegradation in a Mesoscale Landfill Bioreactor

Description: The need to control gas and leachate production and minimize refuse volume in municipal solid waste landfills has motivated the development of landfill simulation models to predict and design optimal treatment processes. We have developed a multiphase and multicomponent nonisothermal module called T2LBM for the three-dimensional TOUGH2 flow and transport simulator. T2LBM can be used to simulate aerobic or anaerobic biodegradation of municipal solid waste and the associated flow and transport of gas and liquid through the refuse mass. Acetic acid is used as a proxy for all biodegradable substrates in the refuse. T2LBM incorporates a Monod kinetic rate law for the biodegradation of acetic acid by either aerobic or anaerobic microbes as controlled by the local oxygen concentration. We have verified the model against published data, and applied it to our own mesoscale laboratory aerobic landfill bioreactor experiments. We observe spatial variability of flow and biodegradation consistent with permeability heterogeneity and the geometry of the radial grid. The model is capable of matching results of a shut-in test where the respiration of the system is measured over time.
Date: February 1, 2002
Creator: Oldenburg, Curtis M.; Borglin, Sharon E. & Hazen, Terry C.
Partner: UNT Libraries Government Documents Department

Laboratory directed research and development program FY 1999

Description: The Ernest Orlando Lawrence Berkeley National Laboratory (Berkeley Lab or LBNL) is a multi-program national research facility operated by the University of California for the Department of Energy (DOE). As an integral element of DOE's National Laboratory System, Berkeley Lab supports DOE's missions in fundamental science, energy resources, and environmental quality. Berkeley Lab programs advance four distinct goals for DOE and the nation: (1) To perform leading multidisciplinary research in the computing sciences, physical sciences, energy sciences, biosciences, and general sciences in a manner that ensures employee and public safety and protection of the environment. (2) To develop and operate unique national experimental facilities for qualified investigators. (3) To educate and train future generations of scientists and engineers to promote national science and education goals. (4) To transfer knowledge and technological innovations and to foster productive relationships among Berkeley Lab's research programs, universities, and industry in order to promote national economic competitiveness. This is the annual report on Laboratory Directed Research and Development (LDRD) program for FY99.
Date: March 8, 2000
Creator: Hansen, Todd & Levy, Karin
Partner: UNT Libraries Government Documents Department

Sequence Compaction to Preserve Transition Frequencies

Description: Simulation-based power estimation is commonly used for its high accuracy despite excessive computation times. Techniques have been proposed to speed it up by compacting an input sequence while preserving its power-consumption characteristics. We propose a novel method to compact a sequence that preserves transition frequencies. We prove the problem is NP-Complete, and propose a graph model to reduce it to that of finding a heaviest weighted trail on a directed graph, along with a heuristic utilizing this model. We also propose using multiple sequences for better accuracy with even shorter sequences. Experiments showed that power dissipation can be estimated with an error of only 2.3 percent, while simulation times are reduced by 10. Proposed methods effectively preserve transition frequencies and generated solutions that are very close to an optimal. Experiments also showed that multiple sequences granted more accurate results with even shorter sequences.
Date: December 12, 2002
Creator: Pinar, Ali & Liu, C.L.
Partner: UNT Libraries Government Documents Department

Bioorganometallic Chemistry, Part 15. A novel molecular recognition process of host, trans-[Cp*Rh({eta}{sup 1}(N3)-1-methylcytosine)({mu}-OH)]{sub 2} (OTf){sub 2}, with l-aromatic amino acid guests: selective hydrogen bonding to the {mu}-OH groups and the 1-methylcytosine ligands

Description: The {sup 1}H-NMR and computer docking experiments have elucidated a novel molecular recognition process of host, trans-[Cp*Rh({eta}{sup 1}(Ne)-1-methylcytosine)({mu}-OH)]{sub 2}(OTf){sub 2} (1), with L-aromatic amino acids, which is predicated on a selective hydrogen bonding regime of the NH{sub 3}{sup +} of the amino acid to one of the Rh-{mu}-OH groups, as well as to a C{double_bond}O group of one of the other 1-methycytosine ligands, while the COO{sup -} H-bonds to an NH{sub 2} of the other 1-methycytosine ligand.
Date: November 1, 2002
Creator: Elduque, Anabel; Carmona, Daniel; Oro, Luis; Eisenstein, Miriam & Fish, Richard H.
Partner: UNT Libraries Government Documents Department

Carbon dioxide reuse and sequestration: The state of the art today

Description: Atmospheric concentrations of CO{sub 2} and other greenhouse gases (GHGs) are growing steadily. GHG levels seem likely to grow more quickly in the future as developed countries continue to use large amounts of energy, while developing countries become wealthy enough to afford energy-intensive automobiles, refrigerators, and other appliances (as well as live and work in larger, more comfortable structures). To keep GHGs at manageable levels, large decreases in CO{sub 2} emissions will be required. Yet analysts understand the difficulty of developing enough zero- and low-carbon-emission technologies to meet the goal of safe GHG stabilization. Carbon sequestration technologies can help bridge this gap. These technologies are only beginning to be developed, but their promise is already evident. In Europe, CO{sub 2} has been continuously and safely pumped into a below-sea limestone structure for over three years, where it remains. In New Mexico, CO{sub 2} is being used to drive out natural gas from within unminable coal seams 1,000 meters below the surface, and again, continuously injected CO{sub 2} has stayed sequestered for over three years, even though the project was designed for natural gas production, not CO{sub 2} sequestration. These and other beginnings suggest that much CO{sub 2} could be reused or sequestered over time. However, substantial R and D will be required so that CO{sub 2} can be captured inexpensively, and then reused or safely sequestered economically. Advanced concepts likely hold great promise as well.
Date: August 1, 2000
Creator: Benson, Sally M.; Dorchak, Thomas; Jacobs, Gary; Ekmann, James; Bishop, Jim & Grahame, Thomas
Partner: UNT Libraries Government Documents Department

Geologic Investigation of a Potential Site for a Next-Generation Reactor Neutrino Oscillation Experiment -- Diablo Canyon, San Luis Obispo County, CA

Description: This report provides information on the geology and selected physical and mechanical properties of surface rocks collected at Diablo Canyon, San Luis Obispo County, California as part of the design and engineering studies towards a future reactor neutrino oscillation experiment. The main objective of this neutrino project is to study the process of neutrino flavor transformation or neutrino oscillation by measuring neutrinos produced in the fission reactions of a nuclear power plant. Diablo Canyon was selected as a candidate site because it allows the detectors to be situated underground in a tunnel close to the source of neutrinos (i.e., at a distance of several hundred meters from the nuclear power plant) while having suitable topography for shielding against cosmic rays. The detectors have to be located underground to minimize the cosmic ray-related background noise that can mimic the signal of reactor neutrino interactions in the detector. Three Pliocene-Miocene marine sedimentary units dominate the geology of Diablo Canyon: the Pismo Formation, the Monterey Formation, and the Obispo Formation. The area is tectonically active, located east of the active Hosgri Fault and in the southern limb of the northwest trending Pismo Syncline. Most of the potential tunnel for the neutrino detector lies within the Obispo Formation. Review of previous geologic studies, observations from a field visit, and selected physical and mechanical properties of rock samples collected from the site provided baseline geological information used in developing a preliminary estimate for tunneling construction cost. Gamma-ray spectrometric results indicate low levels of radioactivity for uranium, thorium, and potassium. Grain density, bulk density, and porosity values for these rock samples range from 2.37 to 2.86 g/cc, 1.41 to 2.57 g/cc, and 1.94 to 68.5 percent respectively. Point load, unconfined compressive strength, and ultrasonic velocity tests were conducted to determine rock mechanical and acoustic properties. The ...
Date: June 11, 2004
Creator: Onishi, Celia Tiemi; Dobson, Patrick; Nakagawa, Seiji; Glaser, Steven & Galic, Dom
Partner: UNT Libraries Government Documents Department

Geologic Investigation of a Potential Site for a Next-Generation Reactor Neutrino Oscillation Experiment -- Diablo Canyon, San Luis Obispo County, CA

Description: This report provides information on the geology and selected physical and mechanical properties of surface rocks collected at Diablo Canyon, San Luis Obispo County, California as part of the design and engineering studies towards a future reactor neutrino oscillation experiment. The main objective of this neutrino project is to study the process of neutrino flavor transformation--or neutrino oscillation--by measuring neutrinos produced in the fission reactions of a nuclear power plant. Diablo Canyon was selected as a candidate site because it allows the detectors to be situated underground in a tunnel close to the source of neutrinos (i.e., at a distance of several hundred meters from the nuclear power plant) while having suitable topography for shielding against cosmic rays. The detectors have to be located underground to minimize the cosmic ray-related background noise that can mimic the signal of reactor neutrino interactions in the detector. Three Pliocene-Miocene marine sedimentary units dominate the geology of Diablo Canyon: the Pismo Formation, the Monterey Formation, and the Obispo Formation. The area is tectonically active, located east of the active Hosgri Fault and in the southern limb of the northwest trending Pismo Syncline. Most of the potential tunnel for the neutrino detector lies within the Obispo Formation. Review of previous geologic studies, observations from a field visit, and selected physical and mechanical properties of rock samples collected from the site provided baseline geological information used in developing a preliminary estimate for tunneling construction cost. Gamma-ray spectrometric results indicate low levels of radioactivity for uranium, thorium, and potassium. Grain density, bulk density, and porosity values for these rock samples range from 2.37 to 2.86 g/cc, 1.41 to 2.57 g/cc, and 1.94 to 68.5% respectively. Point load, unconfined compressive strength, and ultrasonic velocity tests were conducted to determine rock mechanical and acoustic properties. The rock strength values ...
Date: August 1, 2004
Creator: Onishi, Celia Tiemi; Dobson, Patrick; Nakagawa, Seiji; Glaser, Steven & Galic, Dom
Partner: UNT Libraries Government Documents Department

Synchronization of x-ray pulses to the pump laser in an ultrafast x-ray facility

Description: Accurate timing of ultrafast x-ray probe pulses emitted from a synchrotron radiation source with respect to a pump laser exciting processes in the sample under study is critical for the investigation of structural dynamics in the femtosecond regime. We describe a scheme for synchronizing femtosecond x-ray pulses relative to a pump laser. X-ray pulses of <100 fs duration are generated from a proposed source based on a recirculating superconducting linac [1,2,3]. Short x-ray pulses are obtained by a process of electron pulse compression, followed by transverse temporal correlation of the electrons, and ultimately x-ray pulse compression. Timing of the arrival of the x-ray pulse with respect to the pump laser is found to be dominated by the operation of the deflecting cavities which provide the transverse temporal correlation of the electrons. The deflecting cavities are driven from a highly stable RF signal derived from a modelocked laser oscillator which is also the origin of the pump l aser pulses.
Date: May 30, 2002
Creator: Corlett, J.N.; Barry, W.; Byrd, J.M.; Schoenlein, R. & Zholents, A.
Partner: UNT Libraries Government Documents Department

Temperature-dependent x-ray diffraction study of Pd/Cu site interchange in non-Fermi liquid UCu(4)Pd

Description: A pair distribution function (PDF) analysis of temperature-dependent x-ray diffraction measurements from UCu{sub 4}Pd is presented. Fits to the displacement parameters (u{sup 2}'s) with a Debye model show better agreement with a model that includes 25% of the Pd atoms on 16$e$ (Cu) sites. In addition, significant non-thermal disorder is observed in the Cu environment, in contrast to previous measurements of local order in the U-Cu pairs.
Date: June 1, 2002
Creator: Han, S.-W.; Booth, C.H.; Bauer, E.D. & Maple, M.B.
Partner: UNT Libraries Government Documents Department