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Promising X-ray fluorescence tests for superconducting tunneljunction detector

Description: Scientists in the Physical Biosciences Division of the Ernest Orlando Berkeley National Laboratory (Berkeley Lab) studying transition metals in proteins with fluorescence-detected L-edge absorption spectroscopy have found the measurements to be extremely challenging. The difficulty is that the metal centers are present in very dilute concentrations so that their weak fluorescence is often obscured by strong background signals carbon and oxygen. To solve this problem, the Berkeley group has been… more
Date: May 15, 2001
Creator: Friedrich, Stephan & Robinson, Arthur L.
Partner: UNT Libraries Government Documents Department
open access

What Do We Know About Ethanol and Alkylates as Pollutants?

Description: Gov. Davis issued Executive Order D-5-99 in March 1999 calling for removal of methyl tertiary butyl ether (MTBE) from gasoline no later than December 31, 2002. The Executive Order required the California Air Board, State Water Resources Control Board (SWRCB) and Office of Environmental Health Hazard Assessment (OEHHA) to prepare an analysis of potential impacts and health risks that may be associated with the use of ethanol as a fuel oxygenate. The SWRCB contracted with the Lawrence Livermore N… more
Date: May 11, 2001
Creator: Rich, D W; Marchetti, A A; Buscheck, T & Layton, D W
Partner: UNT Libraries Government Documents Department
open access

Measurement of Low Level Explosives Reaction in Gauged Multi-Dimensional Steven Impact Tests

Description: The Steven Test was developed to determine relative impact sensitivity of metal encased solid high explosives and also be amenable to two-dimensional modeling. Low level reaction thresholds occur at impact velocities below those required for shock initiation. To assist in understanding this test, multi-dimensional gauge techniques utilizing carbon foil and carbon resistor gauges were used to measure pressure and event times. Carbon resistor gauges indicated late time low level reactions 200-540… more
Date: May 31, 2001
Creator: Niles, A M; Garcia, F; Greenwood, D W; Forbes, J W; Tarver, C M; Chidester, S K et al.
Partner: UNT Libraries Government Documents Department
open access

Cooperative MPC&A Enhancements at Russian Navy Sites

Description: U.S. MPC&A cooperation with the Russian Federation (RF) Navy is based on a Joint Statement signed in 1996 to protect Highly Enriched Uranium (HEU) fresh fuel used for nuclear propulsion. The Russian Federation Navy is the largest owner in Russia of highly enriched uranium, both in the form of fresh nuclear fuel, and in the form of slightly irradiated fuel with a long cooling time after irradiation. As a result of this agreement, projects began at the Northern Fleet Fresh Fuel Storage Facili… more
Date: May 30, 2001
Creator: Nelson, N. N.; O'Shell, P.; Hendrickson, S.; Sukhoruchkin, V.; Antipov, S.; Melkhov, E. et al.
Partner: UNT Libraries Government Documents Department
open access

The ASCI PSE Milepost: Run-Time Systems Performance Tests

Description: The Accelerated Strategic Computing Initiative (ASCI) Problem Solving Environment (PSE) consists of the tools and libraries needed for the development of ASCI simulation codes on ASCI machines. The recently completed ASCI PSE Milepost demonstrated that this software environment is available and functional at the scale used for application mileposts on ASCI White. As part of the PSE Milepost, we performed extensive performance testing of several critical run-time based systems. In this paper, we… more
Date: May 7, 2001
Creator: de Supinski, B R
Partner: UNT Libraries Government Documents Department
open access

Wet-Etch Figuring: Optical Surfacing by Controlled Application of Etchant Solution Using the marangoni Effect

Description: Wet-etch figuring (WEF), a computer-controlled method for generating arbitrarily shaped optical surfaces using wet chemical etching, has been developed. This method uses applicator geometry and surface tension gradients (the Marangoni Effect) to define and confine the footprint of a wetted etchant zone on the surface. Capillary forces attach the flowing etchant solution to the underside of the optic being figured. No mechanical or thermal stresses or residues are applied to the optic by this pr… more
Date: May 17, 2001
Creator: Rushford, M. C.; Britten, J. A.; Hoaglan, C. R.; Thomas, I. M.; Summers, L. J. & Dixit, S. D.
Partner: UNT Libraries Government Documents Department
open access

Evaluation of MOSFETS and IGBTS for Pulsed Power Applications

Description: Single solid-state devices or arrays of solid-state devices are being incorporated into many pulsed power applications as a means of generating fast, high-power, high repetition-rate pulses and ultimately replacing hard tubes and thyratrons. While vendors' data sheets provide a starting point for selecting solid-state devices, most data sheets do not have sufficient information to determine performance in a pulsed application. To obtain this relevant information, MOSFET's and IGBT's from a numb… more
Date: May 31, 2001
Creator: Hickman, B. & Cook, E.
Partner: UNT Libraries Government Documents Department
open access

Geobotanical Remote Sensing for Geothermal Exploration

Description: This paper presents a plan for increasing the mapped resource base for geothermal exploration in the Western US. We plan to image large areas in the western US with recently developed high resolution hyperspectral geobotanical remote sensing tools. The proposed imaging systems have the ability to map visible faults, surface effluents, historical signatures, and discover subtle hidden faults and hidden thermal systems. Large regions can be imaged at reasonable costs. The technique of geobotanica… more
Date: May 22, 2001
Creator: Pickles, W. L.; Kasameyer, P. W.; Martini, B. A.; Potts, D. C. & Silver, E. A.
Partner: UNT Libraries Government Documents Department
open access

An Analysis of Gas Pressure Forming of Superplastic AL 5083 Alloy

Description: Al 5083 disks of a superplastic forming grade were gas-pressure formed to hemispheres and cones at constant forming pressures with and without back pressure. The forming operation was performed using an in-house designed and built biaxial forming apparatus. The temporal change of dome heights of the hemispheres and cones were measured for the different forming and back pressures applied. The flow stresses and strain rates developed at the top of the dome during the forming step were shown to cl… more
Date: May 4, 2001
Creator: Syn, C K; O'Brien, M J; Lesuer, D R & Sherby, O D
Partner: UNT Libraries Government Documents Department
open access

Army Solid State Laser Program: Design, Operation, and Mission Analysis for a Heat-Capacity Laser

Description: Solid-state lasers have held great promise for the generation of high-average-power, high-quality output beams for a number of decades. However, the inherent difficulty of scaling the active solid-state gain media while continuing to provide efficient cooling has limited demonstrated powers to <5kW. Even at the maximum demonstrated average powers, the output is most often delivered as continuous wave (CW) or as small energy pulses at high pulse repetition frequency (PRF) and the beam diverge… more
Date: May 18, 2001
Creator: Dane, C. B.; Flath, L.; Rotter, M.; Fochs, S.; Brase, J. & Bretney, K.
Partner: UNT Libraries Government Documents Department
open access

Effective Communication and File-I/O Bandwidth Benchmarks

Description: We describe the design and MPI implementation of two benchmarks created to characterize the balanced system performance of high-performance clusters and supercomputers: b{_}eff, the communication-specific benchmark examines the parallel message passing performance of a system, and b{_}eff{_}io, which characterizes the effective 1/0 bandwidth. Both benchmarks have two goals: (a) to get a detailed insight into the Performance strengths and weaknesses of different parallel communication and I/O pa… more
Date: May 2, 2001
Creator: Koniges, A E & Rabenseifner, R
Partner: UNT Libraries Government Documents Department
open access

Keck Adaptive Optics Observations of TW Hydrae Association Members

Description: Adaptive optics (AO) on 8-10 m telescopes is an enormously powerful tool for studying young nearby stars. It is especially useful for searching for companions. Using AO on the 10-m W.M. Keck II telescope we have measured the position of the brown dwarf companion to TWA5 and resolved the primary into an 0.055{double_prime} double. Over the next several years follow-up astrometry should permit an accurate determination of the masses of these young stars. We have also re-observed the candidate ext… more
Date: May 30, 2001
Creator: Macintosh, B; Max, C; Zuckerman, B; Becklin, E E; Kaisler, D; Lowrance, P et al.
Partner: UNT Libraries Government Documents Department
open access

Bayesian Spectroscopy and Target Tracking

Description: Statistical analysis gives a paradigm for detection and tracking of weak-signature sources that are moving among a network of detectors. The detector platforms compute and exchange information with near-neighbors in the form of Bayesian probabilities for possible sources. This can shown to be an optimal scheme for the use of detector information and communication resources. Here, we apply that paradigm to the detection and discrimination of radiation sources using multi-channel gamma-ray spectr… more
Date: May 1, 2001
Creator: Cunningham, C
Partner: UNT Libraries Government Documents Department
open access

The plasticity of human breast carcinoma cells is more than epithelial to mesenchymal conversion

Description: The human breast comprises three lineages: the luminal epithelial lineage, the myoepithelial lineage, and the mesenchymal lineage. It has been widely accepted that human breast neoplasia pertains only to the luminal epithelial lineage. In recent years, however, evidence has accumulated that neoplastic breast epithelial cells may be substantially more plastic in their differentiation repertoire than previously anticipated. Thus, along with an increasing availability of markers for the myoepithel… more
Date: May 12, 2001
Creator: Petersen, Ole William; Nielsen, Helga Lind; Gudjonsson, Thorarinn; Villadsen, René Ronnov-Jessen, Lone & Bissell, Mina J.
Partner: UNT Libraries Government Documents Department
open access

A Comparative experimental study of media access protocols for wireless radio networks

Description: We conduct a comparative experimental analysis of three well known media access protocols: 802.11, CSMA, and MACA for wireless radio networks. Both fixed and ad-hoc networks are considered. The experimental analysis was carried out using GloMoSim: a tool for simulating wireless networks. The main focus of experiments was to study how (i) the size of the network, (ii) number of open connections, (iii) the spatial location of individual connections, (iv) speed with which individual nodes move and… more
Date: May 24, 2001
Creator: Barrett, C. L. (Christopher L.); Drozda, M. (Martin) & Marathe, M. V. (Madhav V.)
Partner: UNT Libraries Government Documents Department
open access

Magnet options for sensors for the pulp and paper industry

Description: The Lawrence Berkeley National Laboratory (LBNL) has been developing sensors for the pulp and paper industry that uses a magnetic field. The applications for magnetic sensors that have studied include (1) sensors for the measurement of the water and ice content of wood chips entering the pulping mill, (2) sensors for measuring the water content and other constituents of the black liquor leaving the paper digester, and (3) sensors for measuring paper thickness and water content as the paper is b… more
Date: May 5, 2001
Creator: Green, M. A.; Barale, P. J.; Fong, C. G.; Luft, P. A.; Reimer, J. A. & Yahnke, M. S.
Partner: UNT Libraries Government Documents Department
open access

Reanalysis of the Schwertmannite structure and the incorporationof SO42- groups: An IR, XAS, WAXS and simulation study

Description: Schwertmannite is a poorly crystallized iron oxyhydroxidewith essential structural sulfate that can be a major component in acidmine drainage environments. Original characterization work concluded thatthe sulfate was largely contained within tunnels of an orderedakaganeite-like structure based on powder XRD, analysis of IR spectra,and sulfate extraction procedures [1]. Since the original description,problems have emerged with the nature of the tunnel sulfate, and with theinterpretation of the I… more
Date: May 5, 2001
Creator: Waychunas, G.A.; Myneni, S.C.B.; Traina, S.J.; Bigham, J.M.; Fuller, C.C. & Davis, J.A.
Partner: UNT Libraries Government Documents Department
open access

A Vortex Contactor for Carbon Dioxide Separations

Description: Many analysts identify carbon dioxide (CO2) capture and separation as a major roadblock in efforts to cost effectively mitigate greenhouse gas emissions via sequestration. An assessment 4 conducted by the International Energy Agency (IEA) Greenhouse Gas Research and Development Programme cited separation costs from $35 to $264 per tonne of CO2 avoided for a conventional coal fired power plant utilizing existing capture technologies. Because these costs equate to a greater than 40% increase in c… more
Date: May 1, 2001
Creator: Raterman, Kevin Thomas; Mc Kellar, Michael George; Turner, Terry Donald; Podgorney, Anna Kristine; Stacey, Douglas Edwin; Stokes, B. et al.
Partner: UNT Libraries Government Documents Department
open access

Requirements Analysis in the Value Methodology

Description: The Value Methodology (VM) study brings together a multidisciplinary team of people who own the problem and have the expertise to identify and solve it. With the varied backgrounds and experiences the team brings to the study, come different perspectives on the problem and the requirements of the project. A requirements analysis step can be added to the Information and Function Analysis Phases of a VM study to validate whether the functions being performed are required, either regulatory or cus… more
Date: May 1, 2001
Creator: Conner, Alison Marie
Partner: UNT Libraries Government Documents Department
open access

Multiple Peaks in the Angular Power Spectrum of the CosmicMicrowave Background: Significance and Consequences for Cosmology

Description: Three peaks and two dips have been detected in the power spectrum of the cosmic microwave background from the BOOMERANG experiment, at {ell} {approx} 210, 540, 840 and {ell} {approx} 420, 750, respectively. Using model-independent analyses, we find that all five features are statistically significant and we measure their location and amplitude. These are consistent with the adiabatic inflationary model. We also calculate the mean and variance of the peak and dip locations and amplitudes in a la… more
Date: May 17, 2001
Creator: de Bernardis, P.; Ade, P. A. R.; Bock, J. J.; Bond, J. R.; Borrill, J.; Boscaleri, A. et al.
Partner: UNT Libraries Government Documents Department
open access

THERM Simulations of Window Indoor Surface Temperatures for Predicting Condensation

Description: As part of a ''round robin'' project, the performance of two wood windows and a Calibrated Transfer Standard was modeled using the THERM heat-transfer simulation program. The resulting interior surface temperatures can be used as input to condensation resistance rating procedures. The Radiation and Condensation Index features within THERM were used to refine the accuracy of simulation results. Differences in surface temperatures between the ''Basic'' calculations and those incorporating the Rad… more
Date: May 18, 2001
Creator: Kohler, Christian; Arasteh, Dariush & Mitchell, Robin
Partner: UNT Libraries Government Documents Department
open access

Obtaining the nuclear gluon distribution from heavy quark decaysto lepton pairs in pA collisions

Description: We have studied how lepton pairs from decays of heavy-flavoured mesons produced in pA collisions can be used to determine the modifications of the gluon distribution in the nucleus. Since heavyquark production is dominated by the gg channel, the ratio of correlated lepton pair cross sections from DD-bar and BB-bar decays in pA and pp collisions directly reflects the ratio R{sub g}A= f{sub g}A/f{sub g}p. We have numerically calculated the lepton pair cross sections from these decays in pp and pA… more
Date: May 10, 2001
Creator: Eskola, K.J.; Kolhinen, V.J. & Vogt, R.
Partner: UNT Libraries Government Documents Department
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