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Measurement of charged particle multiplicities in gluon and quark jets in proton anti-proton collisions at s**(1/2) = 1.8-TeV

Description: The authors report the first model independent measurement of charged particle multiplicities in quark and gluon jets, N{sub q} and N{sub g}, produced at the Tevatron in p{bar p} collisions with center-of-mass energy 1.8 TeV and recorded by the Collider Detector at Fermilab. The measurements are made for jets with average energies 41 and 53 GeV by counting charged particle tracks in cones with opening angle of {theta}{sub c} = 0.28, 0.36, and 0.47 rad around the jet axis. The corresponding jet hardness Q = E{sub jet}{theta}{sub c} varies in the range from 12 GeV to 25 GeV. At Q = 19 GeV, the ratio of multiplicities r = N{sub g}/N{sub q} is found to be 1.64 {+-} 0.17, where statistical and systematic uncertainties are added in quadrature. The results are in agreement with re-summed perturbative QCD calculations.
Date: July 1, 2004
Creator: Acosta, D.; Affolder, Anthony A.; Albrow, M. G.; Ambrose, D.; Amidei, D.; Anikeev, K. et al.
Partner: UNT Libraries Government Documents Department
open access

Monitoring the Energy-Use Effects of Cool Roofs on California Commercial Buildings

Description: Solar-reflective roofs stay cooler in the sun than solar-absorptive roofs. Such ''cool'' roofs achieve lower surface temperatures that reduce heat conduction into the building and the building's cooling load. The California Energy Commission has funded research in which Lawrence Berkeley National Laboratory (LBNL) has measured the electricity use and peak demand in commercial buildings to document savings from implementing the Commission's Cool Roofs program. The study seeks to determine the savings achieved by cool roofs by monitoring the energy use of a carefully selected assortment of buildings participating in the Cool Roofs program. Measurements were needed because the peak savings resulting from the application of cool roofs on different types of buildings in the diverse California climate zones have not been well characterized to date. Only a few occupancy categories (e.g., office and retail buildings) have been monitored before this, and those were done under a limited number of climatic conditions. To help rectify this situation, LBNL was tasked to select the buildings to be monitored, measure roof performance before and after replacing a hot roof by a cool roof, and document both energy and peak demand savings resulting from installation of cool roofs. We monitored the effects of cool roofs on energy use and environmental parameters in six California buildings at three different sites: a retail store in Sacramento; an elementary school in San Marcos (near San Diego); and a 4-building cold storage facility in Reedley (near Fresno). The latter included a cold storage building, a conditioning and fruit-palletizing area, a conditioned packing area, and two unconditioned packing areas (counted as one building).
Date: July 1, 2004
Creator: Akbari, Hashem; Levinson, Ronnen; Konopaki, Steve & Rainer, Leo
Partner: UNT Libraries Government Documents Department
open access

Sub-Angstrom metrology of resolution in aberration-corrected transmission electron microscopes using the A-OK standard test specimens

Description: Using specimens with diamond cubic and zincblende structures, oriented to provide pairs of atoms in ''dumbbell'' configurations, we have identified specimens with well-characterized atom separations over a 3:1 range of spacings straddling the canonical 1 Angstrom value. Spacings ranging from 1.6 Angstrom to 0.5 Angstrom are available from an ''A-OK'' set of test specimens carefully selected for their stability and well-characterized lattice parameters.
Date: July 1, 2004
Creator: Allard, Lawrence F. & O'Keefe, Michael A.
Partner: UNT Libraries Government Documents Department
open access

Synergia: an accelerator modeling tool with 3-D space charge

Description: High precision modeling of space-charge effects, together with accurate treatment of single-particle dynamics, is essential for designing future accelerators as well as optimizing the performance of existing machines. We describe Synergia, a high-fidelity parallel beam dynamics simulation package with fully three dimensional space-charge capabilities and a higher order optics implementation. We describe the computational techniques, the advanced human interface, and the parallel performance obtained using large numbers of macroparticles. We also perform code benchmarks comparing to semi-analytic results and other codes. Finally, we present initial results on particle tune spread, beam halo creation, and emittance growth in the Fermilab booster accelerator.
Date: July 1, 2004
Creator: Amundson, James F.; Spentzouris, P.; Qiang, J. & Ryne, R.
Partner: UNT Libraries Government Documents Department
open access

ES-3100: A New Generation Shipping Container for Bulk Highly Enriched Uranium and Other Fissile Materials

Description: The U.S. Department of Energy (DOE) National Nuclear Security Administration (NNSA) is shipping bulk quantities of surplus fissile materials, primarily highly enriched uranium (HEU), over the next 15 to 20 years for disposition purposes. The U.S. Department of Transportation (DOT) specification 6M container is the package of choice for most of these shipments. However, the 6M does not conform to the Type B packaging requirements in the ''Code of Federal Regulations'' (10CFR71) and, for that reason, is being phased out for use in the secure transportation system of DOE. BWXT Y-12 is currently developing a package to replace the DOT 6M container for HEU disposition shipping campaigns. The new package is based on state-of-the-art, proven, and patented insulation technologies that have been successfully applied in the design of other packages. The new package, designated the ES-3100, will have a 50% greater capacity for HEU than the 6M and will be easier to use. Engineering analysis on the new package includes detailed dynamic impact finite element analysis (FEA). This analysis gives the ES-3100 a high probability of complying with regulatory requirements.
Date: July 1, 2004
Creator: Arbital, J.G.; Byington, G.A. & Tousley, D.R.
Partner: UNT Libraries Government Documents Department
open access

Renewable Energy Water Pumping Systems Handbook; Period of Performance: April 1--September 1, 2001

Description: Water is one of the most basic necessities of rural development. This book provides valuable information on how renewable energy technologies can be used for irrigation, livestock watering, and domestic water supplies. This report emphasizes wind and solar energy resources, and hybrid water pumping systems.
Date: July 1, 2004
Creator: Argaw, N.
Partner: UNT Libraries Government Documents Department
open access

NOVEL COMPOSITE HYDROGEN-PERMEABLE MEMBRANES FOR NON-THERMAL PLASMA REACTORS FOR THE DECOMPOSITION OF HYDROGEN SULFIDE

Description: The goal of this experimental project is to design and fabricate a reactor and membrane test cell to dissociate hydrogen sulfide (H{sub 2}S) in a non-thermal plasma and recover hydrogen (H{sub 2}) through a superpermeable multi-layer membrane. Superpermeability of hydrogen atoms (H) has been reported by some researchers using membranes made of Group V transition metals (niobium, tantalum, vanadium, and their alloys), although it has yet to be confirmed in this study. Experiments involving methane conversion reactions were conducted with a preliminary pulsed corona discharge reactor design in order to test and improve the reactor and membrane designs using a non-toxic reactant. This report details the direct methane conversion experiments to produce hydrogen, acetylene, and higher hydrocarbons utilizing a co-axial cylinder (CAC) corona discharge reactor, pulsed with a thyratron switch. The reactor was designed to accommodate relatively high flow rates (655 x 10{sup -6} m{sup 3}/s) representing a pilot scale easily converted to commercial scale. Parameters expected to influence methane conversion including pulse frequency, charge voltage, capacitance, residence time, and electrode material were investigated. Conversion, selectivity and energy consumption were measured or estimated. C{sub 2} and C{sub 3} hydrocarbon products were analyzed with a residual gas analyzer (RGA). In order to obtain quantitative results, the complex sample spectra were de-convoluted via a linear least squares method. Methane conversion as high as 51% was achieved. The products are typically 50%-60% acetylene, 20% propane, 10% ethane and ethylene, and 5% propylene. First Law thermodynamic energy efficiencies for the system (electrical and reactor) were estimated to range from 38% to 6%, with the highest efficiencies occurring at short residence time and low power input (low specific energy) where conversion is the lowest (less than 5%). The highest methane conversion of 51% occurred at a residence time of 18.8 s with a flow rate …
Date: July 1, 2004
Creator: Argyle, Morris D.; Ackerman, John F.; Muknahallipatna, Suresh; Hamann, Jerry C.; Legowski, Stanislaw; Zhang, Ji-Jun et al.
Partner: UNT Libraries Government Documents Department
open access

A preliminary report on the development of MATLAB tensor classes for fast algorithm prototyping.

Description: We describe three MATLAB classes for manipulating tensors in order to allow fast algorithm prototyping. A tensor is a multidimensional or N-way array. We present a tensor class for manipulating tensors which allows for tensor multiplication and 'matricization.' We have further added two classes for representing tensors in decomposed format: cp{_}tensor and tucker{_}tensor. We demonstrate the use of these classes by implementing several algorithms that have appeared in the literature.
Date: July 1, 2004
Creator: Bader, Brett William & Kolda, Tamara Gibson (Sandia National Laboratories, Livermore, CA)
Partner: UNT Libraries Government Documents Department
open access

Preliminary versions of the MATLAB tensor classes for fast algorithm prototyping.

Description: We present the source code for three MATLAB classes for manipulating tensors in order to allow fast algorithm prototyping. A tensor is a multidimensional or Nway array. This is a supplementary report; details on using this code are provided separately in SAND-XXXX.
Date: July 1, 2004
Creator: Bader, Brett William & Kolda, Tamara Gibson (Sandia National Laboratories, Livermore, CA)
Partner: UNT Libraries Government Documents Department
open access

Fiber Optical Micro-Detectors for Oxygen Sensing in Power Plants Progress Report

Description: A reflection mode fiber optic oxygen sensor that can operate at high temperatures for power plant applications is being developed. The sensor is based on the {sup 3}O{sub 2} quenching of the red emission from hexanuclear molybdenum chloride clusters. Alkali salts of Mo{sub 6}Cl{sub 12} were synthesized and heated to 280 C for one hour in air. Optical measurements of the thermally treated material confirm the potential of the salts as lumophores in high temperature fiber optic sensors. In addition sol-gel films containing Mo{sub 6}Cl{sub 12} were dip coated on quartz substrates and heated at 200 C for one hour. Conditions were developed for successfully immobilizing monomeric complexes that are compatible with sol-gel processing.
Date: July 1, 2004
Creator: Baker, Gregory L.; Ghosh, Ruby N. & III, D.J. Osborn
Partner: UNT Libraries Government Documents Department
open access

Sodium-Bearing Waste Treatment Alternatives Implementation Study

Description: The purpose of this document is to discuss issues related to the implementation of each of the five down-selected INEEL/INTEC radioactive liquid waste (sodium-bearing waste - SBW) treatment alternatives and summarize information in three main areas of concern: process/technical, environmental permitting, and schedule. Major implementation options for each treatment alternative are also identified and briefly discussed. This report may touch upon, but purposely does not address in detail, issues that are programmatic in nature. Examples of these include how the SBW will be classified with respect to the Nuclear Waste Policy Act (NWPA), status of Waste Isolation Pilot Plant (WIPP) permits and waste storage availability, available funding for implementation, stakeholder issues, and State of Idaho Settlement Agreement milestones. It is assumed in this report that the SBW would be classified as a transuranic (TRU) waste suitable for disposal at WIPP, located in New Mexico, after appropriate treatment to meet transportation requirements and waste acceptance criteria (WAC).
Date: July 1, 2004
Creator: Barnes, Charles M.; Bosley, James B. & Olsen, Clifford W.
Partner: UNT Libraries Government Documents Department
open access

A laser-based longitudinal density monitor for the large hadroncollider

Description: We report on the development of an instrument for the measurement of the longitudinal beam profile in the Large Hadron Collider (LHC). The technique used, which has been successfully demonstrated at the Advanced Light Source, mixes the synchrotron radiation with the light from a mode-locked solid state laser oscillator in a non-linear crystal.The up-converted radiation is then detected with a photomultiplier and processed to extract, store and display the required information. A 40MHz laser, phase-locked to the ring radio frequency system, with a 50 pspulse length, would be suitable for measuring the dynamics of the core of each of the LHC 2808 bunches in a time span much shorter than the synchrotron period. The same instrument could also monitor the evolution of the bunch tails, the presence of untrapped particles and their diffusion into nominally empty RF buckets (''ghost bunches'') as required by the CERN specifications.
Date: July 1, 2004
Creator: Beche, J.-F.; Byrd, J.; Datte, P.; De Santis, S.; Placidi, M.; Riot, V. et al.
Partner: UNT Libraries Government Documents Department
open access

Development of an abort gap monitor for the large hadroncollider

Description: The Large Hadron Collider (LHC), presently under construction at CERN, requires monitoring the parasitic charge in the 3.3ms long gap in the machine fill structure. This gap, referred to as the abort gap, corresponds to the raise time of the abort kickers magnets. Any circulating particle present in the abort gap at the time of the kickers firing is lost inside the ring, rather than in the beam dump, and can potentially damage a number of the LHC components. CERN specifications indicate a linear density of 6 x 106 protons over a 100 ns interval as the maximum charge safely allowed to accumulate in the abort gap at 7 TeV. We present a study of an abort gap monitor, based on a photomultiplier tube with a gated microchannel plate, which would allow for detecting such low charge densities by monitoring the synchrotron radiation emitted in the dedicated diagnostics port. We show results of beam test experiments at the Advanced Light Source (ALS) using a Hamamatsu 5961U MCP-PMT, which indicate that such an instrument has the required sensitivity to meet LHC specifications.
Date: July 1, 2004
Creator: Beche, J.-F.; Byrd, J.; De Santis, S.; Placidi, M.; Turner, W. & Zolotorev, M.
Partner: UNT Libraries Government Documents Department
open access

Source and Pathway Determination for Beryllium Found in Bechtel Nevada North Las Vegas Facilities

Description: In response to the report ''Investigation of Beryllium Exposure Cases Discovered at the North Las Vegas Facility of the National Nuclear Security Administration'', published by the U.S. Department of Energy (DOE), National Nuclear Security Administration (NNSA) in August 2003, Bechtel Nevada (BN) President and General Manager Dr. F. A. Tarantino appointed the Beryllium Investigation & Assessment Team (BIAT) to identify both the source and pathway for the beryllium found in the North Las Vegas (NLV) B-Complex. From September 8 to December 18, 2003, the BIAT investigated the pathway for beryllium and determined that a number of locations existed at the Nevada Test Site (NTS) which could have contained sufficient quantities of beryllium to result in contamination if transported. Operations performed in the B-1 Building as a result of characterization activities at the Engine Maintenance, Assembly, and Disassembly (EMAD); Reactor Maintenance, Assembly, and Disassembly (RMAD); Test Cells A and C; and the Central Support Facility in Area 25 had the greatest opportunity for transport of beryllium. Investigative monitoring and sampling was performed at these sites with subsequent transport of sample materials, equipment, and personnel from the NTS to the B-1 Building. The timeline established by the BIAT for potential transport of the beryllium contamination into the B-1 Building was from September 1997 through November 2002. Based on results of recently completed swipe sampling, no evidence of transport of beryllium from test areas has been confirmed. Results less than the DOE beryllium action level of 0.2 ???g/100 cm2 were noted for work support facilities located in Area 25. All of the identified sites in Area 25 worked within the B-1 tenant's residency timeline have been remediated. Legacy contaminants have either been disposed of or capped with clean borrow material. As such, no current opportunity exists for release or spread of beryllium contamination. …
Date: July 1, 2004
Creator: Bechtel Nevada (Firm)
Partner: UNT Libraries Government Documents Department
open access

Tolerance of Three-Stage CIGS Deposition to Variations Imposed by Roll-to-Roll Processing: Phase II Annual Report, May 2003--May 2004

Description: Global Solar Energy, Inc. (GSE) and lower-tier subcontractor ITN Energy Systems, Inc. (ITN) are addressing process tolerance issues in this program. The definition and resolution of process tolerance issues satisfy many of the goals of the Thin Film Photovoltaics Partnerships Program (TFPPP). First, the investigation is likely to identify acceptable ranges for critical deposition parameters. This will have the benefit of providing upper and lower control limits for in-situ process monitoring components, thus increasing average efficiency as well as yield of product. Second, the exploration may uncover insensitivities to some processing procedures, allowing manufacture of modules at increased throughput and decreased cost. The exploration allows a quantitative evaluation of the trade-offs between performance, throughput, and costs. Third, the proposed program also satisfies the TFPPP goal of establishing a wider research and development base for higher-efficiency processing. Four th, the acquisition of data defining sensitivity to processing has important implications for the required accuracy of process sensors and control. Finally, the program helps the photovoltaic community advance toward a better understanding of CIGS growth, a longer-term goal of the TFPPP.
Date: July 1, 2004
Creator: Beck, M. E. & Repins, I. L.
Partner: UNT Libraries Government Documents Department
open access

A nucleon in a tiny box

Description: The authors use Chiral Perturbation Theory to compute the nucleon mass-shift due to finite volume and temperature effects. The results are valid up to next-to-leading order in the ''{epsilon}-regime'' (mL {approx} m{beta} << 1) as well as in the ''p-regime'' (mL {approx} m{beta} >> 1). Based on the two leading orders, they discuss the convergence of the expansion as a function of the lattice size and quark masses. This result can be used to extrapolate lattice results obtained from lattice sizes smaller than the pion cloud, avoiding the numerical simulation of physics under theoretical control. An extraction of the low-energy coefficient c{sub 3} of the chiral Lagrangean from lattice simulations at small volumes and a ''magic'' ratio {beta} = 1.22262 L might be possible.
Date: July 1, 2004
Creator: Bedaque, Paulo F.; Griesshammer, Harald W. & Rupak, Gautam
Partner: UNT Libraries Government Documents Department
open access

SHEAR WAVE SEISMIC STUDY COMPARING 9C3D SV AND SH IMAGES WITH 3C3D C-WAVE IMAGES

Description: The objective of this study was to compare the relative merits of shear-wave (S-wave) seismic data acquired with nine-component (9-C) technology and with three-component (3-C) technology. The original proposal was written as if the investigation would be restricted to a single 9-C seismic survey in southwest Kansas (the Ashland survey), on the basis of the assumption that both 9-C and 3-C S-wave images could be created from that one data set. The Ashland survey was designed as a 9-C seismic program. We found that although the acquisition geometry was adequate for 9-C data analysis, the source-receiver geometry did not allow 3-C data to be extracted on an equitable and competitive basis with 9-C data. To do a fair assessment of the relative value of 9-C and 3-C seismic S-wave data, we expanded the study beyond the Ashland survey and included multicomponent seismic data from surveys done in a variety of basins. These additional data were made available through the Bureau of Economic Geology, our research subcontractor. Bureau scientists have added theoretical analyses to this report that provide valuable insights into several key distinctions between 9-C and 3-C seismic data. These theoretical considerations about distinctions between 3-C and 9-C S-wave data are presented first, followed by a discussion of differences between processing 9-C common-midpoint data and 3-C common-conversion-point data. Examples of 9-C and 3-C data are illustrated and discussed in the last part of the report. The key findings of this study are that each S-wave mode (SH-SH, SV-SV, or PSV) involves a different subsurface illumination pattern and a different reflectivity behavior and that each mode senses a different Earth fabric along its propagation path because of the unique orientation of its particle-displacement vector. As a result of the distinct orientation of each mode's particle-displacement vector, one mode may react to …
Date: July 1, 2004
Creator: Beecherl, John & Hardage, Bob A.
Partner: UNT Libraries Government Documents Department
open access

A Simple Model for Induction Core Voltage Distributions

Description: In fall 2003 T. Hughes of MRC used a full EM simulation code (LSP) to show that the electric field stress distribution near the outer radius of the longitudinal gaps between the four Metglas induction cores is very nonuniform in the original design of the DARHT-2 accelerator cells. In this note we derive a simple model of the electric field distribution in the induction core region to provide physical insights into this result. The starting point in formulating our model is to recognize that the electromagnetic fields in the induction core region of the DARHT-2 accelerator cells should be accurately represented within a quasi-static approximation because the timescale for the fields to change is much longer than the EM wave propagation time. The difficulty one faces is the fact that the electric field is a mixture of both a ''quasi-magnetostatic field'' (having a nonzero curl, with Bdot the source) and a ''quasi-electrostatic field'' (the source being electric charges on the various metal surfaces). We first discuss the EM field structure on the ''micro-scale'' of individual tape windings in Section 2. The insights from that discussion are then used to formulate a ''macroscopic'' description of the fields inside an ''equivalent homogeneous tape wound core region'' in Section 3. This formulation explicitly separates the nonlinear core magnetics from the quasi-electrostatic components of the electric field. In Section 4 a physical interpretation of the radial dependence of the electrostatic component of the electric field derived from this model is presented in terms of distributed capacitances, and the voltage distribution from gap to gap is related to various ''equivalent'' lumped capacitances. Analytic solutions of several simple multi-core cases are presented in Sections 5 and 6 to help provide physical insight into the effect of various proposed changes in the geometrical parameters of the DARHT-2 …
Date: July 1, 2004
Creator: Briggs, Richard J. & Fawley, William M.
Partner: UNT Libraries Government Documents Department
open access

IBACOS Builder System Performance Packages: January 2003 to December 2003

Description: This report presents system design packages for cold and mixed-humid climates. Builders and contractors can use these design packages to construct homes that achieve a Home Energy Rating System (HERS) score between 86 and 88. This represents a reduction in space-conditioning and domestic hot-water energy consumption of between 30% and 40%, compared to a similar home built to meet the 1993 Model Energy Code. The six different design packages, three for each climate zone, give the builder flexibility in their design strategy by allowing them to choose the most cost-effective approach. The recommendations presented in these design packages are based on more than 10 years of experience that IBACOS has had working with builders throughout the United States on Building America projects.
Date: July 1, 2004
Creator: Broniek, J.
Partner: UNT Libraries Government Documents Department
open access

MONITORING POWER PLANT EFFICIENCY USING THE MICROWAVE-EXCITED PHOTOACOUSTIC EFFECT TO MEASURE UNBURNED CARBON

Description: Three test instruments are being evaluated to determine the feasibility of using photoacoustic technology for measuring unburned carbon in fly ash. The first test instrument is a single microwave frequency system previously constructed to measure photoacoustic signals in an off-line configuration. A second off-line instrument was constructed based in part on lessons learned with the first instrument, but which also expands the capabilities of the first instrument. Improvements include a control loop to allow more constant microwave power output and an ability to operate over a range of microwave frequencies. The third instrument, the on-line version of the fly ash monitor, has been designed, constructed, and initial efficiency tests have been conducted on the monitor's electrical components. This quarter focused on improving the signal strength of the accelerometer by increasing the power level of the microwaves that induced the thermo-elastic effect, and also to conduct repeatability experiments. Efforts this quarter were spent improving the coupling of the accelerometer with the diaphragm, detecting and eliminating microwave leakage, isolating stray electrical current within the laboratory, specifically within the ground, and replacing a faulty lock-in amplifier.
Date: July 1, 2004
Creator: Brown, Robert C.; Weber, Robert J. & Sweterlitsch, Jeff
Partner: UNT Libraries Government Documents Department
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An evaluation of the PENCURV model for penetration events in complex targets.

Description: Three complex target penetration scenarios are run with a model developed by the U. S. Army Engineer Waterways Experiment Station, called PENCURV. The results are compared with both test data and a Zapotec model to evaluate PENCURV's suitability for conducting broad-based scoping studies on a variety of targets to give first order solutions to the problem of G-loading. Under many circumstances, the simpler, empirically based PENCURV model compares well with test data and the much more sophisticated Zapotec model. The results suggest that, if PENCURV were enhanced to include rotational acceleration in its G-loading computations, it would provide much more accurate solutions for a wide variety of penetration problems. Data from an improved PENCURV program would allow for faster, lower cost optimization of targets, test parameters and penetration bodies as Sandia National Laboratories continues in its evaluation of the survivability requirements for earth penetrating sensors and weapons.
Date: July 1, 2004
Creator: Broyles, Todd P.
Partner: UNT Libraries Government Documents Department
open access

Coherent infrared radiation from the ALS generated via femtosecond laser modulation of the electron beam

Description: Interaction of an electron beam with a femtosecond laser pulse co-propagating through a wiggler at the ALS produces large modulation of the electron energies within a short {approx}100 fs slice of the electron bunch. Propagating around the storage ring, this bunch develops a longitudinal density perturbation due to the dispersion of electron trajectories. The length of the perturbation evolves with a distance from the wiggler but is much shorter than the electron bunch length. This perturbation causes the electron bunch to emit short pulses of temporally and spatially coherent infrared light which are automatically synchronized to the modulating laser. The intensity and spectra of the infrared light were measured in two storage ring locations for a nominal ALS lattice and for an experimental lattice with the higher momentum compaction factor. The onset of instability stimulated by laser e-beam interaction had been discovered. The infrared signal is now routinely used as a sensitive monitor for a fine tuning of the laser beam alignment during data accumulation in the experiments with femtosecond x-ray pulses.
Date: July 1, 2004
Creator: Byrd, J.M.; Hao, Z.; Martin, M.C.; Robin, D.S.; Sannibale, F.; Schoenlein, R.W. et al.
Partner: UNT Libraries Government Documents Department
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