Serial/Series Title
Clean Cities alternative fuel information series
8
Field Demonstration of a Membrane Process to Separate Nitrogen From Natural Gas Progress Report
7
Fiscal Year 2000
6
Evaluation of Roof Bolting Requirements Based on In-Mine Bolter Drilling Progress Report
5
Fiscal Year 2003
5
Investigation of Efficiency Improvements During CO2 Injection in Hydraulically and Naturally Fractured Reservoirs Progress Report
4
MUSC Environmental Biosciences Progress Report
4
National Bioenergy Center Biochemical Platform Integration Project Quarterly Update
4
Reducing Ultra-Clean Transportation Fuel Costs with HyMelt Hydrogen Quarterly Report
4
Science & Technology Review
4
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Measurement of the azimuthal angle distribution of leptons from W boson decays as a function of the W transverse momentum in p anti-p collisions at s**(1/2) = 1.8-TeV
We present the first measurement of the A{sub 2} and A{sub 3} angular coefficients of the W boson produced in proton-antiproton collisions. We study W {yields} ev{sub e} and W {yields} {mu}{nu}{sub {mu}} candidate events produced in association with at least one jet at CDF, during Run Ia and Run Ib of the Tevatron at {radical}s = 1.8 TeV. The corresponding integrated luminosity was 110 pb{sup -1}. The jet balances the transverse momentum of the W and introduces QCD effects in W boson production. The extraction of the angular coefficients is achieved through the direct measurement of the azimuthal angle of the charged lepton in the Collins-Soper rest-frame of the W boson. The angular coefficients are measured as a function of the transverse momentum of the W boson. The electron, muon, and combined results are in good agreement with the Standard Model prediction, up to order {alpha}{sub s}{sup 2} in QCD.
Date:
April 1, 2005
Creator:
Acosta, D.; Affolder, Anthony A.; Albrow, M. G.; Ambrose, D.; Amidei, D.; Anikeev, K. et al.
Object Type:
Article
System:
The UNT Digital Library
Wind Energy Benefits
Wind energy provides many benefits, including economic and environmental. This two-sided fact sheet succinctly outlines the top ten wind energy benefits and is especially well suited for general audiences.
Date:
April 1, 2005
Creator:
unknown
Object Type:
Text
System:
The UNT Digital Library
What's New: Spring 2005 Update
Articles focus on subjects of interest to Federal agency fleets covered under EPAct and Executive Order 13149.
Date:
April 1, 2005
Creator:
unknown
Object Type:
Text
System:
The UNT Digital Library
Relative stability of silicon self-interstitial defects
{l_brace}311{r_brace} defects and dislocation loops are formed after ion-implantation and annealing of a silicon wafer. Recent Transmission Electron Microscopy studies by Li and Jones have shown that sub-threshold dislocation loops nucleate from {l_brace}311{r_brace} defects. In our study, the conjugate gradient method with the Stillinger Weber potential is used to relax different configurations such as {l_brace}311{r_brace} defects with a maximum of five chains and perfect dislocation loops. From the formation energies thus obtained we find that there is an optimal width for each length of the {l_brace}311{r_brace} defects. Moreover the relative stability of {l_brace}311{r_brace}s and loops is studied as a function of defect size. We observe that at very small sizes the perfect loops are more stable than the {l_brace}311{r_brace}s. This may provide an explanation for the experimental observation by Robertson et al that, in an annealing study of end of range damage of amorphized samples, 45% of the loops had nucleated in the first 10 minutes of anneal. We propose that homogeneous nucleation, as against unfaulting of the {l_brace}311{r_brace}s, could be the source of these loops.
Date:
April 11, 2000
Creator:
Subramanian, G; Jones, K S; Law, M E; Caturla, M J; Theiss, S & Diaz de la Rubia, T
Object Type:
Article
System:
The UNT Digital Library
Characterization and Compensation of High Speed Digitizers
Increasingly, ADC technology is being pressed into service for single single-shot instrumentation applications that were formerly served by vacuum-tube based oscilloscopes and streak cameras. ADC technology, while convenient, suffers significant performance impairments. Thus, in these demanding applications, a quantitative and accurate representation of these impairments is critical to an understanding of measurement accuracy. We have developed a phase-plane behavioral model, implemented it in SIMULINK and applied it to interleaved, high-speed ADCs (up to 4 gigasamples/sec). We have also developed and demonstrated techniques to effectively compensate for these impairments based upon the model.
Date:
April 4, 2005
Creator:
Fong, P; Teruya, A & Lowry, M
Object Type:
Article
System:
The UNT Digital Library
Shock-Dispersed-Fuel Charges: Combustion in Chambers and Tunnels
None
Date:
April 23, 2003
Creator:
Neuwald, P; Reichenbach, H & Kuhl, A L
Object Type:
Article
System:
The UNT Digital Library
Astronomy Applications of Adaptive Optics at Lawrence Livermore National Laboratory
Astronomical applications of adaptive optics at Lawrence Livermore National Laboratory (LLNL) has a history that extends from 1984. The program started with the Lick Observatory Adaptive Optics system and has progressed through the years to lever-larger telescopes: Keck, and now the proposed CELT (California Extremely Large Telescope) 30m telescope. LLNL AO continues to be at the forefront of AO development and science.
Date:
April 23, 2003
Creator:
Bauman, B J & Gavel, D T
Object Type:
Article
System:
The UNT Digital Library
Hybrid Heat Capacity - Moving Slab Laser Concept
A hybrid configuration of a heat capacity laser (HCL) and a moving slab laser (MSL) has been studied. Multiple volumes of solid-state laser material are sequentially diode-pumped and their energy extracted. When a volume reaches a maximum temperature after a ''sub-magazine depth'', it is moved out of the pumping region into a cooling region, and a new volume is introduced. The total magazine depth equals the submagazine depth times the number of volumes. The design parameters are chosen to provide high duty factor operation, resulting in effective use of the diode arrays. The concept significantly reduces diode array cost over conventional heat capacity lasers, and it is considered enabling for many potential applications. A conceptual design study of the hybrid configuration has been carried out. Three concepts were evaluated using CAD tools. The concepts are described and their relative merits discussed. Because of reduced disk size and diode cost, the hybrid concept may allow scaling to average powers on the order of 0.5 MW/module.
Date:
April 1, 2002
Creator:
Stappaerts, E A
Object Type:
Report
System:
The UNT Digital Library
On Issues of Precision for Hardware-based Volume Visualization
This paper discusses issues with the limited precision of hardware-based volume visualization. We will describe the compositing OVER operator and how fixed-point arithmetic affects it. We propose two techniques to improve the precision of fixed-point compositing and the accuracy of hardware-based volume visualization. The first technique is to perform dithering of color and alpha values. The second technique we call exponent-factoring, and captures significantly more numeric resolution than dithering, but can only produce monochromatic images.
Date:
April 11, 2003
Creator:
LaMar, E C
Object Type:
Article
System:
The UNT Digital Library
K0(s) and Lambda0 production studies in p anti-p collisions at s**(1/2) = 1800 and 630-GeV
The authors present a study of the production of K{sub s}{sup 0} and {Lambda}{sup 0} in inelastic p{bar p} collisions at {radical}s = 1800 and 630 GeV using data collected by the CDF experiment at the Fermilab Tevatron. Analyses of K{sub s}{sup 0} and {Lambda}{sup 0} multiplicity and transverse momentum distributions, as well as of the dependencies of the average number and (p{sub T}) of K{sub s}{sup 0} and {Lambda}{sup 0} on charged particle multiplicity are reported. Systematic comparisons are performed for the full sample of inelastic collisions, and for the low and high momentum transfer subsamples, at the two energies. The p{sub T} distributions extend above 8 GeV/c, showing a (p{sub T}) higher than previous measurements. The dependence of the mean K{sub s}{sup 0}({Lambda}{sup 0}) p{sub T} on the charged particle multiplicity for the three samples shows a behavior analogous to that of charged primary tracks.
Date:
April 1, 2005
Creator:
Acosta, D.; Affolder, Anthony A.; Albrow, M. G.; Ambrose, D.; Amidei, D.; Anikeev, K. et al.
Object Type:
Article
System:
The UNT Digital Library
Field Verification Project for Small Wind Turbines Quarterly Report; July-September 2001, 3rd Quarter, Issue#6
This newsletter provides a brief overview of the Field Verification Project for Small Wind Turbines conducted at the NWTC and a description of current activities. The newsletter also contains case studies of current projects.
Date:
April 1, 2003
Creator:
unknown
Object Type:
Text
System:
The UNT Digital Library
Building a Bridge to the Ethanol Industry--Follow-up Project: Period of Performance; February 22, 2001- December 31, 2002
Subcontract report summarizing results of a trial of a corn fiber pretreatment process. The results of the trial showed that the carbohydrates in the pretreated liquid and solid streams are readily hydrolyzed by enzymes and easily fermentable to ethanol by yeast.
Date:
April 1, 2003
Creator:
Ladisch, M.; Mosier, N.; Welch, G. & Dien, B.
Object Type:
Report
System:
The UNT Digital Library
X-Ray Line Measurements with High Efficiency Bragg Crystals
We have studied the focusing properties of two highly oriented pyrolitic graphite (HOPG) spectrometers, which differ in the degree of the mosaic spread: ZYA with a low mosaic spread ({gamma}=0.4 degrees) and ZYH with a large mosaic spread ({gamma}=3.5 degrees). In order to assess the crystal performance for a variety of different experiments, various K{alpha} and K{beta} x-ray lines have been produced using a high-intensity ({approx}>10{sup 17} W/cm{sup 2}) short-pulse ({approx} 100 fs) laser beam focused onto Ti, V, Zn, and Cu foils. The measured spectral resolution of the HOPG crystals in both first and second order diffraction has been compared with theoretical predictions. Using known values for the peak reflectivity of HOPG crystals, we have also computed K{alpha} x-ray conversion efficiencies of Ti, V, Zn, and Cu. These results are important to estimate the optimal conditions under which different types of HOPG monochromators can be used for the detection of weak x-ray signals as the one encountered in x-ray Thomson/Compton scattering experiments.
Date:
April 1, 2004
Creator:
Pak, A; Gregori, G; Knight, J; Campbell, K; Landen, O & Glenzer, S
Object Type:
Article
System:
The UNT Digital Library
A study on D0 Run2b stave structural performance
Two different structural solutions have been proposed and studied for the D0 Run2b stave (Figure 1 and Figure 3). The way the stave structural stiffness is achieved in both designs is essentially the same: the structural material is displaced as far as possible from the neutral axis in order to increase the bending moment of the stave. The agreement of the measured data with what has been theoretically predicted is excellent. The C channel stave with dog-bones glued on top of the sensor (stave No.2) has outperformed the other mockups with a predicted sag of 51 {micro}m for a distributed load of 2.28 N/m [0.013 lbf/in] and a consequent natural frequency of 89.2Hz. The other three C channel staves with the dog-bones not glued on the sensor have a bending stiffness that is -19.0%, -10.8%, +4.0% of that of stave No.2, being 11.0%, 7.8%, 15.1% lighter respectively. An optimized stave structural proposal with 130.5% of the design stiffness within the mass budget is presented at the end of this paper.
Date:
April 1, 2002
Creator:
Lanfranco, Giobatta
Object Type:
Report
System:
The UNT Digital Library
Large Eddy Simulation of Turbulent Flow and Dispersion in Urban Areas and Forest Canopies
Under the sponsorship of the U.S. DOE and DHS, we have developed a CFD model for simulating flow and dispersion of chemical and biological agents released in the urban environment. Our model, FEM3MP (Chan and Stevens, 2000), is based on solving the three-dimensional, time-dependent, incompressible Navier-Stokes equations on massively parallel computer platforms. The model uses the finite element method for accurate representation of complex building shapes and variable terrain, together with a semi-implicit projection method and modern iterative solvers for efficient time integration (Gresho and Chan, 1998). Physical processes treated include turbulence modeling via the RANS (Reynolds Averaged Navier-Stokes) and LES (Large Eddy Simulation) approaches, atmospheric stability, aerosols, UV radiation decay, surface energy budget, and vegetative canopies, etc. Predictions from our model are continuously being verified and validated against data from wind tunnel (Chan and Stevens, 2000; Chan, et al., 2001) and field experiments (Chan, et al., 2002, 2003; Lee, et al., 2002; Humphreys, et al., 2003; and Calhoun, et al., 2004). Discussed below are several examples to illustrate the use of FEM3MP in simulating flow and dispersion in urban areas and forest canopies, with model results compared against available field measurements.
Date:
April 9, 2004
Creator:
Chan, Stevens T.
Object Type:
Article
System:
The UNT Digital Library
Background reduction in cryogenic detectors
This paper discusses the background reduction and rejection strategy of the Cryogenic Dark Matter Search (CDMS) experiment. Recent measurements of background levels from CDMS II at Soudan are presented, along with estimates for future improvements in sensitivity expected for a proposed SuperCDMS experiment at SNOLAB.
Date:
April 1, 2005
Creator:
Bauer, Daniel A.
Object Type:
Article
System:
The UNT Digital Library
SEA - A Simplified Employee Assessment
This paper presents a proposal for modifying the current employee annual evaluation process in SCAD. It purports to simplify that process, primarily by breaking up the resultant document into a set of more or less independent components. It claims to reduce the overall time and effort required from each actor.
Date:
April 23, 2001
Creator:
Busby, L
Object Type:
Report
System:
The UNT Digital Library
DOE Advanced Controls R&D Planning Workshop, June 11, 2003, Washington DC: Workshop Results
On June 11, 2003, representatives from universities, federal and state government agencies, Department of Energy national laboratories, and the private sector attended a one-day workshop in Washington, DC. The objective of the workshop was to review and provide input into DOE's assessment of the market for advanced sensors and controls technology and potential R&D pathways to enhance their success in the buildings market place. The workshop consisted of two sessions. During the morning session, participants were given an overview on the following topics: market assessment, current applications and strategies for new applications, sensors and controls, networking, security, and protocols and standards, and automated diagnostics, performance measurement, commissioning and optimal control and tools. In the sessions, workshop participants were asked to review the potential R&D pathways, identify high priority activities, and outline a five year path for each of these activities. Priorities were as follows: largest and quickest impact; best use of finite resources; greatest likelihood for market penetration; and ability to replicate results. The participants identified several promising R&D opportunities.
Date:
April 13, 2005
Creator:
Brambley, Michael R.; Haves, Philip; McDonald, Sean C.; Torcellini, Paul; Hansen, David G.; Holmberg, David et al.
Object Type:
Report
System:
The UNT Digital Library
Measurement of the polarization of the K-shell resonance line emission of S13+ and S14+ at relativistic electron beam energies.
We have measured the polarization of the heliumlike sulfur resonance line 1s2p {sup 1}P{sub 1} {yields} 1s{sup 2} {sup 1}S{sub 0}, and of the blend of the lithiumlike sulfur resonance lines 1s2s2p {sup 2}P{sub 3/2} {yields} 1s{sup 2}2s {sup 2}S{sub 1/2} and 1s2s2p {sup 2}P{sub 1/2} {yields} 1s{sup 2}2s {sup 2}S{sub 1/2} as a function of electron beam energy from near threshold to 144 keV. These lines were excited with the LLNL high-energy electron beam ion trap and measured using a newly modified two-crystal technique. Our results test polarization predictions in an energy regime where few empirical results have been reported. We also present calculations of the polarization using two different methods, and good agreement is obtained.
Date:
April 6, 2004
Creator:
Robbins, D; Faenov, A Y; Pikuz, T; Chen, H; Beiersdorfer, P; May, M et al.
Object Type:
Article
System:
The UNT Digital Library
Biological Review of the Hanford Solid Waste EIS - Borrow Area C (600 Area), Stockpile and Conveyance Road Area (600 Area), Environmental Restoration Disposal Facility (ERDF) (600 Area), Central Waste Complex (CWC) Expansion (200 West), 218-W-5 Expansion Area (200 West), New Waste Processing Facility (200 West)...ECR No. 2002-600-012b
This letter report is a supplement to the letter reports submitted previously under ECRs No. 2002-600-012 (Borrow Area C) and No. 2002-600-012a (CWC expansion). This letter report covers all areas that may be subject to surface disturbance under Alternative Groups A, B, C, D1, D2, D3, E1, E2, E3, and the No Action Alternative of the Hanford Solid Waste Environmental Impact Statement (HSW EIS), except for the following Low-Level Burial Grounds (LLBGs). The LLBGs proposed for use in the HSW EIS that are not subject of this letter report (218-W-3A, 218-W-3AE, 218-W 4B, 218-W-5, the developed portion of 218-W-4C, and the eastern half [except the northeastern corner] of 218-W-6 in the 200 West Area; and 218-E-10 and 218-E-12B in the 200 East Area) are surveyed annually. Annual letter reports concerning these are currently sent to Mr. Brett M. Barnes of Fluor Hanford, Inc. For the areas of surface disturbance described herein we provide a summary of field survey methods, survey results, and considerations and recommendations based on these results.
Date:
April 7, 2003
Creator:
Sackschewsky, Michael R.
Object Type:
Report
System:
The UNT Digital Library
Final Focus Spot Size in a Solenoid Focusing System
A linear lens can focus a cold beam to a singular point. Unfortunately, this ideal situation would never occur in the real world. Besides nonlinearity of the lens, any deviation of the beam parameters from the ideal beam's nominal beam parameters would lead to nonzero final spot size. In other words, the final spot size of a beam focused by a focusing lens with a given focusing strength depends on its beam parameters, such as the emittance, variations in beam current, energy, envelope and envelope slopes, and nonlinearity of the focusing lens. There are many types of final focusing systems. We consider only the system using a ''thin'' solenoid lens in this notes. Generally, the net focusing force in a solenoid focusing system is not sensitive to the beam current for an emittance dominated beam. For simplicity, we will ignore the space charge forces in the discussion, and focus on the contributions of beam emittance, energy variation and nonlinearity of the lens to the final spot size here.
Date:
April 8, 2003
Creator:
Chen, Y. J.
Object Type:
Report
System:
The UNT Digital Library
NIF HEPW 2D Radiography Option Survey
None
Date:
April 28, 2004
Creator:
Koch, J
Object Type:
Report
System:
The UNT Digital Library
HUNTING THE QUARK GLUON PLASMA.
The U.S. Department of Energy's Relativistic Heavy Ion Collider (RHIC) construction project was completed at BNL in 1999, with the first data-taking runs in the summer of 2000. Since then the early measurements at RHIC have yielded a wealth of data, from four independent detectors, each with its international collaboration of scientists: BRAHMS, PHENIX, PHOBOS, and STAR [1]. For the first time, collisions of heavy nuclei have been carried out at colliding-beam energies that have previously been accessible only for high-energy physics experiments with collisions of ''elementary'' particles such as protons and electrons. It is at these high energies that the predictions of quantum chromodynamics (QCD), the fundamental theory that describes the role of quarks and gluons in nuclear matter, come into play, and new phenomena are sought that may illuminate our view of the basic structure of matter on the sub-atomic scale, with important implications for the origins of matter on the cosmic scale. The RHIC experiments have recorded data from collisions of gold nuclei at the highest energies ever achieved in man-made particle accelerators. These collisions, of which hundreds of millions have now been examined, result in final states of unprecedented complexity, with thousands of produced particles radiating …
Date:
April 11, 2005
Creator:
LUDLAM, T. & ARONSON, S.
Object Type:
Report
System:
The UNT Digital Library
Effect of Structural Modification on Second Harmonic Generation in Collagen
The effects of structural perturbation on second harmonic generation in collagen were investigated. Type I collagen fascicles obtained from rat tails were structurally modified by increasing nonenzymatic cross-linking, by thermal denaturation, by collagenase digestion, or by dehydration. Changes in polarization dependence were observed in the dehydrated samples. Surprisingly, no changes in polarization dependence were observed in highly crosslinked samples, despite significant alterations in packing structure. Complete thermal denaturation and collagenase digestion produced samples with no detectable second harmonic signal. Prior to loss of signal, no change in polarization dependence was observed in partially heated or digested collagen.
Date:
April 4, 2003
Creator:
Stoller, P C; Reiser, K M; Celliers, P M & Rubenchik, A M
Object Type:
Article
System:
The UNT Digital Library