Autonomous Pathogen Detection System (open access)

Autonomous Pathogen Detection System

None
Date: February 18, 2004
Creator: Hindson, Benjamin; McBride, Mary; Makarewicz, Anthony; Henderer, Bruce; Sathyam, Ujwal; Nasarabadi, Shanavaz et al.
Object Type: Article
System: The UNT Digital Library
Laser Coupling to Reduced-Scale Targets at the Early Light Program of the National Ignition Facility (open access)

Laser Coupling to Reduced-Scale Targets at the Early Light Program of the National Ignition Facility

A platform for analysis of material properties under extreme conditions, where a sample is bathed in radiation with a high temperature, is under development. This hot environment is produced with a laser by depositing maximum energy into a small, high-Z can. Such targets were recently included in an experimental campaign using the first four of the 192 beams of the National Ignition Facility, under construction at the University of California Lawrence Livermore National Laboratory. These targets demonstrate good laser coupling, reaching a radiation temperature of 340 eV. In addition, there is a unique wavelength dependence of the Raman backscattered light that is consistent with Brillouin backscatter of Raman forward scatter [A. B. Langdon and D. E. Hinkel, Physical Review Letters 89, 015003 (2002)]. Finally, novel diagnostic capabilities indicate that 20% of the direct backscatter from these reduced-scale targets is in the polarization orthogonal to that of the incident light.
Date: November 18, 2004
Creator: Hinkel, D. E.; Schneider, M. B.; Baldis, H. A.; Bower, D.; Campbell, K. M.; Celeste, J. R. et al.
Object Type: Article
System: The UNT Digital Library
Microstructure and Creep Properties of TiAl-Ti3Al In-Situ Composites (open access)

Microstructure and Creep Properties of TiAl-Ti3Al In-Situ Composites

Objectives: {lg_bullet} Exploit thermomechanical-processing techniques to fabricate TiAl/Ti3Al in-situ laminate composites with the size of lamella width down to submicron or nanometer length-scales. {lg_bullet} Characterize microstructure and elevated-temperature creep resistance of the in-situ composites. {lg_bullet} Investigate the fundamental interrelationships among microstructures, alloying additions, and mechanical properties of the in-situ composites so as to achieve the desired properties of the in-situ composites for high-temperature structural applications.
Date: February 18, 2004
Creator: Hodge, A M & Hsiung, L L
Object Type: Report
System: The UNT Digital Library
IMPROVEMENT OF WEAR COMPONENT'S PERFORMANCE BY UTILIZING ADVANCED MATERIALS AND NEW MANUFACTURING TECHNOLOGIES: CASTCON PROCESS FOR MINING APPLICATIONS (open access)

IMPROVEMENT OF WEAR COMPONENT'S PERFORMANCE BY UTILIZING ADVANCED MATERIALS AND NEW MANUFACTURING TECHNOLOGIES: CASTCON PROCESS FOR MINING APPLICATIONS

During this reporting period, we mainly focused on solving the disc distortion problem that was encountered in the last quarter. A slower heating rate during off-gassing was tested to reduce the HIPping can expansion. However, slight expansion still occurred. Two 6.5 inch discs were produced with many defects. One was made of H13 powder only and the other was made of H13 powder with WC inserts. It was believed that the defects were caused by the slight expansion of the HIP can during the elevated temperature off-gassing and a vacuum leak in the HIPping can.
Date: March 18, 2004
Creator: Huang, Xiaodi & Gertsch, Richard
Object Type: Report
System: The UNT Digital Library
A Tribute to George F. Pinder (open access)

A Tribute to George F. Pinder

In the fall of 2001 a Special Session was convened at the Fall Meeting of the American Geophysical Union as a tribute to George F. Pinder's contributions to groundwater modeling in the last thirty-five years. At a subsequent meeting of the editorial board of Advances in Water Resources (AWR), we reflected on George's contributions to the field of groundwater hydrology and his particular contributions to AWR, which he co-founded in 1977 with Carlos A. Brebbia. It was at this meeting that the seed for compiling a special issue of AWR in honor of George's contributions was sown.
Date: February 18, 2004
Creator: Imhoff, P T & Tompson, A F
Object Type: Article
System: The UNT Digital Library
Low-cost flexible packaging for high-power Li-Ion HEV batteries. (open access)

Low-cost flexible packaging for high-power Li-Ion HEV batteries.

Batteries with various types of chemistries are typically sold in rigid hermetically sealed containers that, at the simplest level, must contain the electrolyte while keeping out the exterior atmosphere. However, such rigid containers can have limitations in packaging situations where the form of the battery is important, such as in hand-held electronics like personal digital assistants (PDAs), laptops, and cell phones. Other limitations exist as well. At least one of the electrode leads must be insulated from the metal can, which necessitates the inclusion of an insulated metal feed-through in the containment hardware. Another limitation may be in hardware and assembly cost, such as exists for the lithium-ion batteries that are being developed for use in electric vehicles (EVs) and hybrid electric vehicles (HEVs). The large size (typically 10-100 Ah) of these batteries usually results in electric beam or laser welding of the metal cap to the metal can. The non-aqueous electrolyte used in these batteries are usually based on flammable solvents and therefore require the incorporation of a safety rupture vent to relieve pressure in the event of overcharging or overheating. Both of these features add cost to the battery. Flexible packaging provides an alternative to the rigid container. …
Date: June 18, 2004
Creator: Jansen, A. N.; Amine, K. & Henriksen, G. L.
Object Type: Report
System: The UNT Digital Library
Real-Time Chord Length Analysis of Strontium and Manganese Precipitates Formed from Hanford Tank 241-AN-107 Simulant (open access)

Real-Time Chord Length Analysis of Strontium and Manganese Precipitates Formed from Hanford Tank 241-AN-107 Simulant

Removal of radioactive strontium and transuranic elements from Hanford Envelope C waste solutions can be accomplished by the sequential addition of sodium hydroxide, strontium nitrate, and sodium permanganate solutions. This multistep precipitation process is the baseline technology in the River Protection Project -Waste Treatment Plant (RPP-WTP) for the removal of these radioactive species from Hanford Waste Tanks. Decontamination targets are easily met using these precipitation technologies and current work in this area focuses on optimization to minimize reagent levels. Downstream treatment processes require filtration of the precipitate slurry. In order to avoid further precipitation after filtration, it is necessary to know the precipitation reaction time-scale. In addition, precipitate slurry filter flux is a primary parameter of interest to plant design personnel. Optimization of the filtration process is benefited by an understanding of the parameters that impact particle size distribution. Filter cake packing and, hence, filter flux are often sensitive to small changes in the particle size distribution. However, traditional methods of particle size analysis often are not sufficiently sensitive to develop correlations to filterability. Focused Beam Reflectance Measurements (FBRM) are a relatively new chord length analysis method with extremely high sensitivity. The method is suited for continuous monitoring of chord …
Date: March 18, 2004
Creator: KING, WILLIAMD
Object Type: Report
System: The UNT Digital Library
PROCEEDINGS OF RIKEN BNL RESEARCH CENTER WORKSHOP, VOLUME 57, HIGH PT PHYSICS AT RHIC, DECEMBER 2-6, 2003 (open access)

PROCEEDINGS OF RIKEN BNL RESEARCH CENTER WORKSHOP, VOLUME 57, HIGH PT PHYSICS AT RHIC, DECEMBER 2-6, 2003

The AuAu, dAu, and pp collision modes of the RHIC collider at BNL have led to the publication of exciting high p{perpendicular} particle production data. There have also been two physics runs with polarized protons, and preliminary results on the double-spin asymmetry for pion production had been presented very recently. The ontological questions behind these measurements are fascinating: Did RHIC collisions create a Quark-Gluon-Plasma phase and did they verify the Color Glass Condensate as the high energy limit of QCD? Will the Spin Crisis finally be resolved in terms of gluon polarization and what new surprises are we yet to meet for Transverse Spin? Phenomena related to sub-microscopic questions as important as these call for interpretations that are footed in solid theory. At large p{perpendicular}, perturbative concepts are legitimately expected to provide useful approaches. The corresponding hard parton dynamics are, in several ways, key to unraveling the initial or final state and collisional phase of hard scattering events in vacuum as well as in hot or cold nuclear matter. Before the advent of RHIC data, a RIKEN-BNL workshop had been held at BNL in March 1999 on ''Hard Parton Physics in High Energy Nuclear Collisions''. The 2003 workshop on ''High …
Date: February 18, 2004
Creator: KRETZER,S. MORRISON,D. VENUGOPALAN,R. VOGELSANG,W.
Object Type: Report
System: The UNT Digital Library
A Hybrid Ion-Source Concept for a Proton Driver Front-End (open access)

A Hybrid Ion-Source Concept for a Proton Driver Front-End

A novel concept for creating intense beams of negative hydrogen ion beams has been devised, and first steps towards its realization have been taken. In this approach, an ECR plasma generator operating at 2.45 GHz frequency is utilized as a plasma cathode, and electrons are extracted instead of ions and injected at moderate energy into an SNS type multi-cusp H{sup -} ion source. This secondary source is then driven by chopped d. c. power, rather than rf power, but does not need filaments which are the cause for the rather short lifetime of conventional H{sup -} sources. The development of this ion source is primarily aimed at the future beam-power goal of 3 MW for the Spallation Neutron Source (SNS) [1] that will be pursued after the start of SNS operations. The first two phases of this development effort have been successfully passed: assembly of a test stand and verification of the performance of an rf-driven SNS ion-source prototype and extraction of electrons with more than 200 mA current from a 2.45-GHz ECR ion source obtained on loan from Argonne National Laboratory. An electron-extraction chamber that joins these ECR and H{sup -} sources has been fabricated, and the next goal …
Date: October 18, 2004
Creator: Keller, R.; Luft, P.; Regis, M.; Wallig, J.; Monroy, M.; Ratti,A. et al.
Object Type: Article
System: The UNT Digital Library
Evidence for a Proton Transfer Network and a Required Persulfide-Bond-Forming Cysteine Residue in Ni-Containing Carbon Monoxide Dehydrogenases (open access)

Evidence for a Proton Transfer Network and a Required Persulfide-Bond-Forming Cysteine Residue in Ni-Containing Carbon Monoxide Dehydrogenases

OAK-B135 Carbon monoxide dehydrogenase from Moorella thermoacetica catalyzes the reversible oxidation of CO to CO2 at a nickel-iron-sulfur active-site called the C-cluster. Mutants of a proposed proton transfer pathway and of a cysteine residue recently found to form a persulfide bond with the C-cluster were characterized. Four semi-conserved histidine residues were individually mutated to alanine. His116 and His122 were essential to catalysis, while His113 and His119 attenuated catalysis but were not essential. Significant activity was ''rescued'' by a double mutant where His116 was replaced by Ala and His was also introduced at position 115. Activity was also rescued in double mutants where His122 was replaced by Ala and His was simultaneously introduced at either position 121 or 123. Activity was also ''rescued'' by replacing His with Cys at position 116. Mutation of conserved Lys587 near the C-cluster attenuated activity but did not eliminate it. Activity was virtually abolished in a double mutant where Lys587 and His113 were both changed to Ala. Mutations of conserved Asn284 also attenuated activity. These effects suggest the presence of a network of amino acid residues responsible for proton transfer rather than a single linear pathway. The Ser mutant of the persulfide-forming Cys316 was essentially inactive …
Date: May 18, 2004
Creator: Kim, Eun Jin; Feng, Jian; Bramlett, Matthew R. & Lindahl, Paul A.
Object Type: Article
System: The UNT Digital Library
Annual Technical Progress Report of Radioisotope Power System Materials Production and Technology Program Tasks for October 1, 2002 Through September 30, 2003 (open access)

Annual Technical Progress Report of Radioisotope Power System Materials Production and Technology Program Tasks for October 1, 2002 Through September 30, 2003

The Office of Space and Defense Power Systems of the Department of Energy (DOE) provides Radioisotope Power Systems (RPS) for applications where conventional power systems are not feasible. For example, radioisotope thermoelectric generators were supplied by the DOE to the National Aeronautics and Space Administration for deep space missions including the Cassini Mission launched in October of 1997 to study the planet Saturn. The Oak Ridge National Laboratory (ORNL) has been involved in developing materials and technology and producing components for the DOE for more than three decades. For the Cassini Mission, for example, ORNL was involved in the production of carbon-bonded carbon fiber (CBCF) insulator sets, iridium alloy blanks and foil, and clad vent sets (CVS). This report has been divided into three sections to reflect program guidance from the Office of Space and Defense Power Systems for fiscal year (FY) 2003. The first section deals primarily with maintenance of the capability to produce flight quality (FQ) CBCF insulator sets, iridium alloy blanks and foil, and CVS. In all three cases, production maintenance is assured by the manufacture of limited quantities of FQ components. The second section deals with several technology activities to improve the manufacturing processes, characterize materials, …
Date: May 18, 2004
Creator: King, J.F.
Object Type: Report
System: The UNT Digital Library
A new phase of matter in Oakland (open access)

A new phase of matter in Oakland

Recent results from the Relativistic Heavy Ion Collider (RHIC) and the phase diagram of matter at very high energies were the focal points of Quark Matter 2004, held January 10-17, 2004 in the Oakland, California convention center. About 700 participants, including 125 students, from 28 countries gathered for 5 days of plenary and parallel sessions. Besides the scientific discussions, participants enjoyed an afternoon of excursions; choices included visits to San Francisco, the Muir woods, and, of course, a chance to sample Napa Valley wines. There was also a day of introductory lectures for graduate students and a separate afternoon program for 50 local high school teachers. The ''Quark Matter'' conference series has evolved into the premier venue for relativistic heavy ion collisions, and QM2004 was no exception. The 44 plenary and 92 parallel session talks featured a veritable flood of data from STAR (Kai Schweda, LBNL), PHENIX (Tony Frawley, Florida State), PHOBOS (Peter Steinberg, BNL) and BRAHMS (Michael Murray, Kansas), at RHIC. This was accompanied by contributions from HERMES ( Pasquale DiNezza, Frascati) and HERA-B (Joakim Spengler, Heidelberg) and continuing analyses from NA-49 (Marek Gazdzicki, Frankfurt) and NA-57 (Giuseppe Bruno, Bari) at the CERN SPS. The theoretical contributions presented a …
Date: March 18, 2004
Creator: Klein, Spencer & Nystrand, Joakim
Object Type: Article
System: The UNT Digital Library
Physical processes controlling dark current emission and resulting breakdown in Linacs. (open access)

Physical processes controlling dark current emission and resulting breakdown in Linacs.

Higher accelerating gradients are required for future high-power devices such as the TeV electron linear collider and muon-muon collider. A limit in the maximum field gradient is imposed by the rf dark current and the resulting electrical breakdown. Two critical questions need to be answered: What causes high dark current and breakdown? Can the breakdown threshold be increased? These problems have been the focus of significant experimental and theoretical investigations for over a century. The purpose of this report is to shed some light on the possible mechanisms that limit the field gradient in linacs with and without guiding magnetic fields. The idea of enhanced field emission due to separation of grains from a material surface by the electric field tension acting normally to the surface is discussed. The electric force can be high enough to overcome the binding energy of grains in the material. Thus, small-size separated grains result in enhanced field emission. The stopping power of relativistic and ultra-relativistic energies of ejected electrons at high electric field results in more production of secondary electrons. At high energy, E>>mc{sup 2}, the stopping power of relativistic and ultra-relativistic electrons becomes similar to the stopping power of ions with the same …
Date: March 18, 2004
Creator: Konkashbaev, I. & Hassanein, A.
Object Type: Report
System: The UNT Digital Library
The Multi-State Anti-Terrorism Information Exchange (MATRIX) Pilot Project (open access)

The Multi-State Anti-Terrorism Information Exchange (MATRIX) Pilot Project

None
Date: August 18, 2004
Creator: Krouse, William J.
Object Type: Report
System: The UNT Digital Library
Broadband Internet Access and the Digital Divide: Federal Assistance Programs (open access)

Broadband Internet Access and the Digital Divide: Federal Assistance Programs

This report is on Broadband Internet Access and the Digital Divide: Federal Assistance Programs.
Date: May 18, 2004
Creator: Kruger, Lennard G.
Object Type: Report
System: The UNT Digital Library
Teacher Recruitment and Retention: Current Programs and Legislation in the 108th Congress (open access)

Teacher Recruitment and Retention: Current Programs and Legislation in the 108th Congress

Congressional Research Service (CRS) report entailing information about current programs and legislation in the 108th Congress, in regards to teacher recruitment and retention. Topics include, current federal programs, non-federal programs, legislation in the 108th congress, etc..
Date: February 18, 2004
Creator: Kuenzi, Jeffrey J.
Object Type: Report
System: The UNT Digital Library
Effect of Oxalate on the Recycle of Neptunium Filtrate Solution by Anion Exchange (open access)

Effect of Oxalate on the Recycle of Neptunium Filtrate Solution by Anion Exchange

A series of laboratory column runs has been performed that demonstrates the recovery of neptunium (Np) containing up to 0.05 M oxalate. Np losses were generally less than one percent to the raffinate for feed solutions that contained 2 to 10 g Np/L. Up to 16 percent Np losses were observed with lower Np feed concentrations, but those losses were attributed to the shortened residence times rather than the higher oxalate to Np ratios. Losses in the plant are expected to be significantly less due to the lower cross-section flowrate possible with existing plant pumps. Elimination of the permanganate treatment of filtrates appears to be reasonable since the amount of Np in those filtrates does not appear to be practical to recover. Combination of untreated filtrates with other actinide rich solutions is not advisable as precipitation problems are likely. If untreated filtrates are kept segregated from other actinide rich streams, the recovery of the remaining Np is probably still possible, but could be limited due to the excessively high oxalate to Np ratio. The persistence of hydrazine/hydrazoic acid in filtrate solutions dictates that the nitrite treatment be retained to eliminate those species from the filtrates prior to transfer to the …
Date: November 18, 2004
Creator: Kyser, E
Object Type: Report
System: The UNT Digital Library
Computational Methods for Collisional Plasma Physics (open access)

Computational Methods for Collisional Plasma Physics

Modeling the high density, high temperature plasmas produced by intense laser or particle beams requires accurate simulation of a large range of plasma collisionality. Current simulation algorithms accurately and efficiently model collisionless and collision-dominated plasmas. The important parameter regime between these extremes, semi-collisional plasmas, has been inadequately addressed to date. LLNL efforts to understand and harness high energy-density physics phenomena for stockpile stewardship require accurate simulation of such plasmas. We have made significant progress towards our goal: building a new modeling capability to accurately simulate the full range of collisional plasma physics phenomena. Our project has developed a computer model using a two-pronged approach that involves a new adaptive-resolution, ''smart'' particle-in-cell algorithm: complex particle kinetics (CPK); and developing a robust 3D massively parallel plasma production code Z3 with collisional extensions. Our new CPK algorithms expand the function of point particles in traditional plasma PIC models by including finite size and internal dynamics. This project has enhanced LLNL's competency in computational plasma physics and contributed to LLNL's expertise and forefront position in plasma modeling. The computational models developed will be applied to plasma problems of interest to LLNL's stockpile stewardship mission. Such problems include semi-collisional behavior in hohlraums, high-energy-density physics experiments, …
Date: February 18, 2004
Creator: Lasinski, B. F.; Larson, D. J.; Hewett, D. W.; Langdon, A. B. & Still, C. H.
Object Type: Report
System: The UNT Digital Library
Studies of nondegenerate, quasi-phase-matched optical parametric amplification (open access)

Studies of nondegenerate, quasi-phase-matched optical parametric amplification

We have performed extensive numerical studies of quasi-phase-matched optical parametric amplification with the aim to improve its nondegenerate spectral bandwidth. Our multi-section fan-out design calculations indicate a 35-fold increase in spectral bandwidth.
Date: March 18, 2004
Creator: Lawrence Livermore National Laboratory
Object Type: Article
System: The UNT Digital Library
Compact neutron generator developement and applications (open access)

Compact neutron generator developement and applications

The Plasma and Ion Source Technology Group at the Lawrence Berkeley National Laboratory has been engaging in the development of high yield compact neutron generators for the last ten years. Because neutrons in these generators are formed by using either D-D, T-T or D-T fusion reaction, one can produce either mono-energetic (2.4 MeV or 14 MeV) or white neutrons. All the neutron generators being developed by our group utilize 13.5 MHz RF induction discharge to produce a pure deuterium or a mixture of deuterium-tritium plasma. As a result, ion beams with high current density and almost pure atomic ions can be extracted from the plasma source. The ion beams are accelerated to {approx}100 keV and neutrons are produced when the beams impinge on a titanium target. Neutron generators with different configurations and sizes have been designed and tested at LBNL. Their applications include neutron activation analysis, oil-well logging, boron neutron capture therapy, brachytherapy, cargo and luggage screening. A novel small point neutron source has recently been developed for radiography application. The source size can be 2 mm or less, making it possible to examine objects with sharper images. The performance of these neutron generators will be described in this paper.
Date: January 18, 2004
Creator: Leung, Ka-Ngo; Reijonen, Jani; Gicquel, Frederic; Hahto, Sami & Lou, Tak-Pui
Object Type: Article
System: The UNT Digital Library
Offshoring (a.k.a. Offshore Outsourcing) and Job Insecurity Among U.S. Workers (open access)

Offshoring (a.k.a. Offshore Outsourcing) and Job Insecurity Among U.S. Workers

None
Date: June 18, 2004
Creator: Levine, Linda
Object Type: Report
System: The UNT Digital Library
Military Base Closures: A Historical Review from 1988 to 1995 (open access)

Military Base Closures: A Historical Review from 1988 to 1995

This report discusses a concerted effort to close unneeded military bases as part of wide-ranging efforts during the 1980s and 1990s to balance the budget. This effort had been supported by a broad consensus that, among the approximately 3,800 military bases (1990 est.) in the United States, many could be closed without significant detrimental effect to national security. While most analysts agreed that the department of Defense's (DOD's) base structure was larger than necessary to meet the department's needs, there were differences concerning which, if any, additional bases should be closed, at what speed, and what criteria should be used for making those decisions.
Date: October 18, 2004
Creator: Lockwood, David E. & Siehl, George
Object Type: Report
System: The UNT Digital Library
Military Base Closures: A Historical Review from 1988 to 1995 (open access)

Military Base Closures: A Historical Review from 1988 to 1995

The United States has experienced difficulty in closing military bases to match the requirements of downsized forces with changed composition. During the decade of the 1980s, major military base closures were seriously hampered by procedural requirements established by Congress, to the point that none occurred. The mismatch between real estate assets and defense requirements grew with the military downsizing that began late in the Reagan Administration and continued under Presidents George H. W. Bush and Clinton.
Date: October 18, 2004
Creator: Lockwood, David E. & Siehl, George
Object Type: Report
System: The UNT Digital Library
Development of Burning Plasma and Advanced Scenarios in the DIII-D Tokamak (open access)

Development of Burning Plasma and Advanced Scenarios in the DIII-D Tokamak

Significant progress in the development of burning plasma scenarios, steady-state scenarios at high fusion performance, and basic tokamak physics has been made by the DIII-D Team. Discharges similar to the ITER baseline scenario have demonstrated normalized fusion performance nearly 50% higher than required for Q = 10 in ITER, under stationary conditions. Discharges that extrapolate to Q {approx} 10 for longer than one hour in ITER at reduced current have also been demonstrated in DIII-D under stationary conditions. Proof of high fusion performance with full noninductive operation has been obtained. Underlying this work are studies validating approaches to confinement extrapolation, disruption avoidance and mitigation, tritium retention, ELM avoidance, and operation above the no-wall pressure limit. In addition, the unique capabilities of the DIII-D facility have advanced studies of the sawtooth instability with unprecedented time and space resolution, threshold behavior in the electron heat transport, and rotation in plasmas in the absence of external torque.
Date: October 18, 2004
Creator: Luce, T C
Object Type: Article
System: The UNT Digital Library