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University Press (Beaumont, Tex.), Vol. 79, No. 10, Ed. 1 Friday, October 18, 2002 (open access)

University Press (Beaumont, Tex.), Vol. 79, No. 10, Ed. 1 Friday, October 18, 2002

Semiweekly newspaper from Lamar University in Beaumont, Texas that includes local, national, and campus news along with advertising.
Date: October 18, 2002
Creator: Achilles, Jenny
Object Type: Newspaper
System: The Portal to Texas History
University Press (Beaumont, Tex.), Vol. 79, No. 11, Ed. 1 Wednesday, October 23, 2002 (open access)

University Press (Beaumont, Tex.), Vol. 79, No. 11, Ed. 1 Wednesday, October 23, 2002

Semiweekly newspaper from Lamar University in Beaumont, Texas that includes local, national, and campus news along with advertising.
Date: October 23, 2002
Creator: Achilles, Jenny
Object Type: Newspaper
System: The Portal to Texas History
University Press (Beaumont, Tex.), Vol. 79, No. 13, Ed. 1 Friday, October 25, 2002 (open access)

University Press (Beaumont, Tex.), Vol. 79, No. 13, Ed. 1 Friday, October 25, 2002

Semiweekly newspaper from Lamar University in Beaumont, Texas that includes local, national, and campus news along with advertising.
Date: October 25, 2002
Creator: Achilles, Jenny
Object Type: Newspaper
System: The Portal to Texas History
University Press (Beaumont, Tex.), Vol. 79, No. 14, Ed. 1 Wednesday, October 30, 2002 (open access)

University Press (Beaumont, Tex.), Vol. 79, No. 14, Ed. 1 Wednesday, October 30, 2002

Semiweekly newspaper from Lamar University in Beaumont, Texas that includes local, national, and campus news along with advertising.
Date: October 30, 2002
Creator: Achilles, Jenny
Object Type: Newspaper
System: The Portal to Texas History
Macro-ions collapse leading to hybrid bio-nanomaterials. (open access)

Macro-ions collapse leading to hybrid bio-nanomaterials.

I used supramolecular self-assembling cyanine and the polyamine spermine binding to Escherichia coli genomic DNA as a model for DNA collapse during high throughput screening. Polyamine binding to DNA converts the normally right handed B-DNA into left handed Z-DNA conformation. Polyamine binding to DNA was inhibited by the supramolecular self-assembling cyanine. Self-assembly of cyanine upon DNA scaffold was likewise competitively inhibited by spermine as signaled by fluorescence quench from DNA-cyanine ensemble. Sequence of DNA exposure to cyanine or spermine was critical in determining the magnitude of fluorescence quench. Methanol potentiated spermine inhibition by >10-fold. The IC{sub 50} for spermine inhibition was 0.35 {+-} 0.03 {micro}M and the association constant Ka was 2.86 x 10{sup -6}M. Reversibility of the DNA-polyamine interactions was evident from quench mitigation at higher concentrations of cyanine. System flexibility was demonstrated by similar spermine interactions with {lambda}DNA. The choices and rationale regarding the polyamine, the cyanine dye as well as the remarkable effects of methanol are discussed in detail. Cyanine might be a safer alternative to the mutagenic toxin ethidium bromide for investigating DNA-drug interactions. The combined actions of polyamines and alcohols mediate DNA collapse producing hybrid bio-nanomaterials with novel signaling properties that might be useful in …
Date: October 1, 2009
Creator: Achyuthan, Komandoor E.
Object Type: Report
System: The UNT Digital Library
Combined U-Th/He and 40Ar/39Ar geochronology of post-shield lavas from the Mauna Kea and Kohala volcanoes, Hawaii (open access)

Combined U-Th/He and 40Ar/39Ar geochronology of post-shield lavas from the Mauna Kea and Kohala volcanoes, Hawaii

Late Quaternary, post-shield lavas from the Mauna Kea and Kohala volcanoes on the Big Island of Hawaii have been dated using the {sup 40}Ar/{sup 39}Ar and U-Th/He methods. The objective of the study is to compare the recently demonstrated U-Th/He age method, which uses basaltic olivine phenocrysts, with {sup 40}Ar/{sup 39}Ar ages measured on groundmass from the same samples. As a corollary, the age data also increase the precision of the chronology of volcanism on the Big Island. For the U-Th/He ages, U, Th and He concentrations and isotopes were measured to account for U-series disequilibrium and initial He. Single analyses U-Th/He ages for Hamakua lavas from Mauna Kea are 87 {+-} 40 ka to 119 {+-} 23 ka (2{sigma} uncertainties), which are in general equal to or younger than {sup 40}Ar/{sup 39}Ar ages. Basalt from the Polulu sequence on Kohala gives a U-Th/He age of 354 {+-} 54 ka and a {sup 40}Ar/{sup 39}Ar age of 450 {+-} 40 ka. All of the U-Th/He ages, and all but one spurious {sup 40}Ar/{sup 39}Ar ages conform to the previously proposed stratigraphy and published {sup 14}C and K-Ar ages. The ages also compare favorably to U-Th whole rock-olivine ages calculated from …
Date: October 1, 2009
Creator: Aciego, S.M.; Jourdan, F.; DePaolo, D.J.; Kennedy, B.M.; Renne, P.R. & Sims, K.W.W.
Object Type: Article
System: The UNT Digital Library
Global Climate Change: Selected Legal Questions About the Kyoto Protocol (open access)

Global Climate Change: Selected Legal Questions About the Kyoto Protocol

This report addresses legal issues after the United States signed the Kyoto Protocol to the UnitedNations Framework Convention on Climate Change. The protocol is not yet in effect internationally and cannot be legally binding on the U.S. unless and until the Senate gives its advice and consent.
Date: October 1, 2002
Creator: Ackerman, David M.
Object Type: Report
System: The UNT Digital Library
Atmospheric Radiation Measurement Program Science Plan (open access)

Atmospheric Radiation Measurement Program Science Plan

The Atmospheric Radiation Measurement (ARM) Program has matured into one of the key programs in the U.S. Climate Change Science Program. The ARM Program has achieved considerable scientific success in a broad range of activities, including site and instrument development, atmospheric radiative transfer, aerosol science, determination of cloud properties, cloud modeling, and cloud parameterization testing and development. The focus of ARM science has naturally shifted during the last few years to an increasing emphasis on modeling and parameterization studies to take advantage of the long time series of data now available. During the next 5 years, the principal focus of the ARM science program will be to: Maintain the data record at the fixed ARM sites for at least the next five years. Improve significantly our understanding of and ability to parameterize the 3-D cloud-radiation problem at scales from the local atmospheric column to the global climate model (GCM) grid square. Continue developing techniques to retrieve the properties of all clouds, with a special focus on ice clouds and mixed-phase clouds. Develop a focused research effort on the indirect aerosol problem that spans observations, physical models, and climate model parameterizations. Implement and evaluate an operational methodology to calculate broad-band heating …
Date: October 31, 2004
Creator: Ackerman, T
Object Type: Report
System: The UNT Digital Library
Atmospheric Radiation Measurement Program Science Plan Current Status and Future Directions of the ARM Science Program (open access)

Atmospheric Radiation Measurement Program Science Plan Current Status and Future Directions of the ARM Science Program

The Atmospheric Radiation Measurement (ARM) Program has matured into one of the key programs in the U.S. Climate Change Science Program. The ARM Program has achieved considerable scientific success in a broad range of activities, including site and instrument development, atmospheric radiative transfer, aerosol science, determination of cloud properties, cloud modeling, and cloud parameterization testing and development. The focus of ARM science has naturally shifted during the last few years to an increasing emphasis on modeling and parameterization studies to take advantage of the long time series of data now available. During the next 5 years, the principal focus of the ARM science program will be to: • Maintain the data record at the fixed ARM sites for at least the next five years. • Improve significantly our understanding of and ability to parameterize the 3-D cloud-radiation problem at scales from the local atmospheric column to the global climate model (GCM) grid square. • Continue developing techniques to retrieve the properties of all clouds, with a special focus on ice clouds and mixed-phase clouds. • Develop a focused research effort on the indirect aerosol problem that spans observations, physical models, and climate model parameterizations. • Implement and evaluate an operational …
Date: October 30, 2004
Creator: Ackerman, TP; Genio, AD Del; Ellingson, RG; Ferrare, RA; Klein, SA; McFarquhar, GM et al.
Object Type: Report
System: The UNT Digital Library
Small space object imaging : LDRD final report. (open access)

Small space object imaging : LDRD final report.

We report the results of an LDRD effort to investigate new technologies for the identification of small-sized (mm to cm) debris in low-earth orbit. This small-yet-energetic debris presents a threat to the integrity of space-assets worldwide and represents significant security challenge to the international community. We present a nonexhaustive review of recent US and Russian efforts to meet the challenges of debris identification and removal and then provide a detailed description of joint US-Russian plans for sensitive, laser-based imaging of small debris at distances of hundreds of kilometers and relative velocities of several kilometers per second. Plans for the upcoming experimental testing of these imaging schemes are presented and a preliminary path toward system integration is identified.
Date: October 1, 2009
Creator: Ackermann, Mark R.; Valley, Michael T. & Kearney, Sean Patrick
Object Type: Report
System: The UNT Digital Library
Exotic physics: search for scalar leptoquark pairs decaying to nu nu-bar qq-bar in p anti-p collisions at s**(1/2) = 1.96 tev (open access)

Exotic physics: search for scalar leptoquark pairs decaying to nu nu-bar qq-bar in p anti-p collisions at s**(1/2) = 1.96 tev

We report on a search for the pair production of scalar leptoquarks, LQ, using 191 pb{sup -1} of proton-antiproton collision data recorded by the CDF experiment during Run II of the Tevatron. The leptoquarks are sought via their decay into a neutrino and quark yielding missing transverse energy and several jets of large transverse energy. No evidence for leptoquark production is observed, and limits are set on {sigma}(p{bar p} {yields} LQ{ovr OQ}X {yields} v{bar v}q{bar q}X). Using a next-to-leading order theoretical prediction of the cross section for scalar leptoquark production, we exclude first-generation leptoquarks in the mass interval 78 to 117 GeV/c{sup 2} at the 95% confidence level for BR(LQ {yields} vq) = 100%.
Date: October 25, 2004
Creator: Acosta, D.
Object Type: Report
System: The UNT Digital Library
Top physics: measurement of the tt-bar production cross section in pp-bar collisions at s**(1/2) = 1.96 tev using dilepton event (open access)

Top physics: measurement of the tt-bar production cross section in pp-bar collisions at s**(1/2) = 1.96 tev using dilepton event

We report a measurement of the t{bar t} production cross section using dilepton events with jets and missing transverse energy in p{bar p} collisions at a center-of-mass energy of 1.96 TeV. Using a 197 {+-} 12 pb{sup -1} data sample recorded by the upgraded Collider Detector at Fermilab, we use two complementary techniques to select candidate events. We compare the number of observed events and selected kinematical distributions with the predictions of the standard model and find good agreement. The combined result of the two techniques yields a t{bar t} production cross section of 7.0{sub -2.1}{sup +2.4}(stat){sub -1.1}{sup _1.6}(syst) {+-} 0.4(lum) pb.
Date: October 14, 2004
Creator: Acosta, D.
Object Type: Report
System: The UNT Digital Library
Sulfur Polymer Stabilization/Solidification (Spss) Treatability of Simulated Mixed-Waste Mercury Contaminated Sludge. (open access)

Sulfur Polymer Stabilization/Solidification (Spss) Treatability of Simulated Mixed-Waste Mercury Contaminated Sludge.

The Environmental Protection Agency (EPA) is currently seeking to validate technologies that can directly treat radioactively contaminated high mercury (Hg) subcategory wastes without removing the mercury from the waste. The Sulfur Polymer Stabilization/Solidification (SPSS) process developed at Brookhaven National Laboratory is one of several candidate technologies capable of successfully treating various Hg waste streams. To supplement previously supplied data on treatment of soils, EPA needs additional data concerning stabilization of high Hg subcategory waste sludges. To this end, a 5000 ppm sludge surrogate, containing approximately 50 wt% water, was successfully treated by pilot-scale SPSS processing. In two process runs, 85 and 95 wt% of water was recovered from the sludge during processing. At waste loadings of 30 wt% dry sludge, the treated waste form had no detectable mercury (<10 ppb) in TCLP leachates. Data gathered from the demonstration of treatment of this sludge will provide EPA with information to support revisions to current treatment requirements for high Hg subcategory wastes.
Date: October 1, 2002
Creator: Adama, J. W.; Bowerman, B. S. & Kalb, P. D.
Object Type: Report
System: The UNT Digital Library
Micromilling of Metal Alloys with Focused Ion Beam-Fabricated Tools (open access)

Micromilling of Metal Alloys with Focused Ion Beam-Fabricated Tools

None
Date: October 3, 2000
Creator: Adams, D.P.; Vasile, M.J.; Benavides, G.L. & Campbell, A.N.
Object Type: Article
System: The UNT Digital Library
Wavelength and pulselength dependence of laser conditioning and bulk damage in doubler-cut KH2PO4 (open access)

Wavelength and pulselength dependence of laser conditioning and bulk damage in doubler-cut KH2PO4

An experimental technique has been utilized to measure the variation of bulk damage scatter with damaging fluence in plates of KH{sub 2}PO{sub 4} (KDP) crystals. Bulk damage in unconditioned and laser-conditioned doubler-cut KDP crystals has been studied using 527 nm (2{omega}) light at pulselengths of 0.3-10 ns. It is found that there is less scatter due to damage at fixed fluence for longer pulselengths. In particular, there is {approx}4X increase in fluence for equivalent scatter for damage at 2{omega}, 10 ns as compared to 0.30 ns in unconditioned KDP. The results for the unconditioned and conditioned KDP show that for all the pulselengths the scatter due to the bulk damage is a strong function of the damaging fluence ({phi}{sup -5}). It is determined that the 2{omega} fluence pulselength-scaling for equivalent bulk damage scatter in unconditioned KDP varies as {tau}{sup 0.30{+-}0.11} and in 3{omega}, 3ns ramp-conditioned KDP varies as {tau}{sup 0.27{+-}0.14}. The effectiveness of 2{omega} and 3{omega} laser conditioning at pulselengths in the range of 0.30-23 ns for damage induced 2{omega}, 3 ns is analyzed in terms of scatter. For the protocols tested (i.e. peak conditioning irradiance, etc.), the 3{omega}, 300 ps conditioning to a peak fluence of 3 J/cm{sup 2} …
Date: October 28, 2005
Creator: Adams, J. J.; Bruere, J. R.; Bolourchi, M.; Carr, C. W.; Feit, M. D.; Hackel, R. P. et al.
Object Type: Article
System: The UNT Digital Library
Comparison between S/1 and R/1 tests and damage density vs. fluence (rho(phi)) results for unconditioned and sub-nanosecond laser-conditioned KD2PO4 crystals (open access)

Comparison between S/1 and R/1 tests and damage density vs. fluence (rho(phi)) results for unconditioned and sub-nanosecond laser-conditioned KD2PO4 crystals

We present S/1 and R/1 test results on unconditioned and 355 nm (3{omega}), 500 ps laser conditioned DKDP. We find up to {approx}2.5X improvement in fluence in the S/1 performance after 3{omega}, 500 ps conditioning to 5 J/cm{sup 2}. For the first time, we observe a shift to higher fluences in the R/1 results for DKDP at 3{omega}, 7 ns due to 500 ps laser conditioning. The S/1 results are compared to {rho}({phi}) results previously measured on the same DKDP crystal [1]. A consistent behavior in fluence was found between the S/1 and {rho}({phi}) results for unconditioned and 500 ps conditioned DKDP. We were successful at using Poisson statistics to derive a connection between the S/1 and {rho}({phi}) results that could be tested with our data sets by trying to predict the shape of the {rho}({phi}) curve. The value for the power dependence on fluence of {rho}({phi}) derived from the S/1 data was {approx}11 {+-} 50%. The results presented and discussed here imply a strong correlation between the damage probability (S/1) test and {rho}({phi}). We find a consistent description of the two test types in terms of a power law {rho}({phi}) and that this basic shape held for all cases, …
Date: October 31, 2007
Creator: Adams, J. J.; Jarboe, J.; Feit, M. & Hackel, R.
Object Type: Article
System: The UNT Digital Library
Azimuthal anisotropy at RHIC: The first and fourth harmonics (open access)

Azimuthal anisotropy at RHIC: The first and fourth harmonics

No abstract prepared.
Date: October 28, 2003
Creator: Adams, J.; Adler, C.; Aggarwal, M. M.; Ahammed, Z.; Amonett, J.; Anderson, B. D. et al.
Object Type: Article
System: The UNT Digital Library
Cross sections and transverse single-spin asymmetries in forward neutral pion production from proton collisions at sqrt(s) = 200 GeV (open access)

Cross sections and transverse single-spin asymmetries in forward neutral pion production from proton collisions at sqrt(s) = 200 GeV

No abstract prepared.
Date: October 29, 2003
Creator: Adams, J.; Adler, C.; Aggarwal, M. M.; Ahammed, Z.; Amonett, J.; Anderson, B. D. et al.
Object Type: Article
System: The UNT Digital Library
Identified particle distributions in pp and Au+Au collisions atsqrt sNN=200 GeV (open access)

Identified particle distributions in pp and Au+Au collisions atsqrt sNN=200 GeV

Transverse mass and rapidity distributions for charged pions, charged kaons, protons and antiprotons are reported for {radical}sNN = 200 GeV pp and Au+Au collisions at RHIC. The transverse mass distributions are rapidity independent within |y| < 0.5, consistent with a boost-invariant system in this rapidity interval. Spectral shapes and relative particle yields are similar in pp and peripheral Au+Au collisions and change smoothly to central Au+Au collisions. No centrality dependence was observed in the kaon and antiproton production rates relative to the pion production rate from medium-central to central collisions. Chemical and kinetic equilibrium model fits to our data reveal strong radial flow and relatively long duration from chemical to kinetic freeze-out in central Au+Au collisions. The chemical freeze-out temperature appears to be independent of initial conditions at RHIC energies.
Date: October 6, 2003
Creator: Adams, J.; Adler, C.; Aggarwal, M. M.; Ahammed, Z.; Amonett, J.; Anderson, B. D. et al.
Object Type: Article
System: The UNT Digital Library
Computational Modeling of K-shell Argon Spectra from Z-pinch Dynamic Hohlraum Experiments (open access)

Computational Modeling of K-shell Argon Spectra from Z-pinch Dynamic Hohlraum Experiments

Z-pinch dynamic hohlraum experiments on the Z-Machine at Sandia National Laboratories measured K-shell argon spectra using a focusing spectrometer with spatial resolution. The spectra are modeled using Hullac atomic data input, Cretin nonlocal thermodynamic equilibrium (nlte) atomic kinetics and radiative transfer calculations, and Dakota optimization capabilities. Hullac provides atomic structure and cross section data for Ar XIX, Ar XXVIII (n=1 (illegible) 5), Ar XXVII (n=1 (illegible) 10), and Ar XXVI (n=1 (illegible) 5), where n is the principal quantum number. Cretin calculates the area-integrated spectral intensity escaping an argon doped Dcapsule as a function of electron density, electron temperature, and capsule radius. Dakota optimizes the plasma properties for the best to the measured spectrum by minimizing an objective function comprise of argon spectral line ratios and full-width at half-maximums (fwhms). We highlight the framework of this general spectroscopic capability and discuss the extension to magnetized plasmas using Totalb spectral line shapes.
Date: October 27, 2004
Creator: Adams, M L; Sinars, D B; Scott, H A; Brandon, S T; Chung, H K & Lee, R W
Object Type: Article
System: The UNT Digital Library
Scaling to 150K cores: recent algorithm and performance engineering developments enabling XGC1 to run at scale (open access)

Scaling to 150K cores: recent algorithm and performance engineering developments enabling XGC1 to run at scale

Particle-in-cell (PIC) methods have proven to be eft#11;ective in discretizing the Vlasov-Maxwell system of equations describing the core of toroidal burning plasmas for many decades. Recent physical understanding of the importance of edge physics for stability and transport in tokamaks has lead to development of the fi#12;rst fully toroidal edge PIC code - XGC1. The edge region poses special problems in meshing for PIC methods due to the lack of closed flux surfaces, which makes fi#12;eld-line following meshes and coordinate systems problematic. We present a solution to this problem with a semi-#12;field line following mesh method in a cylindrical coordinate system. Additionally, modern supercomputers require highly concurrent algorithms and implementations, with all levels of the memory hierarchy being effe#14;ciently utilized to realize optimal code performance. This paper presents a mesh and particle partitioning method, suitable to our meshing strategy, for use on highly concurrent cache-based computing platforms.
Date: October 1, 2009
Creator: Adams, Mark F.; Ku, Seung-Hoe; Worley, Patrick; D'Azevedo, Ed; Cummings, Julian C. & Chang, C. S.
Object Type: Article
System: The UNT Digital Library
Synthesis and Characterization of Cluster-Derived Supported Bimetallic Catalysts (open access)

Synthesis and Characterization of Cluster-Derived Supported Bimetallic Catalysts

New procedures have been developed for synthesizing di- and tri-metallic cluster complexes. The chemical properties of the new complexes have been investigated, particularly toward the activation of molecular hydrogen. These complexes were then converted into bi- and tri-metallic nanoparticles on silica and alumina supports. These nanoparticles were characterized by electron microscopy and were then tested for their ability to produce catalytic hydrogenation of unsaturated hydrocarbons and for the preferential oxidation of CO in the presence of hydrogen. The bi- and tri-metallic nanoparticles exhibited far superior activity and selectivity as hydrogenation catalysts when compared to the individual metallic components. It was found that the addition of tin greatly improved the selectivity of the catalysts for the hydrogenation of polyolefins. The addition of iron improves the catalysts for the selective oxidation of CO by platinum in the presence of hydrogen. The observations should lead to the development of lower cost routes to molecules that can be used to produce polymers and plastics for use by the general public and for procedures to purify hydrogen for use as an alternative energy in the hydrogen economy of the future.
Date: October 10, 2008
Creator: Adams, Richard D & Amiridis, Michael D
Object Type: Report
System: The UNT Digital Library
Quarterly Progress Report - Biological Monitoring Program for East Fork Poplar Creek (open access)

Quarterly Progress Report - Biological Monitoring Program for East Fork Poplar Creek

In May 1985, a National Pollutant Discharge Elimination System (NPDES) permit was issued for the Oak Ridge Y-12 Plant. As a condition of the permit, a Biological Monitoring and Abatement Program (BMAP) was developed to demonstrate that the effluent limitations established for the Y-12 Plant protect the classified uses of the receiving stream (East Fork Poplar Creek; EFPC), in particular, the growth and propagation of aquatic life (Loar et al. 1989). A second objective of the BMAP is to document the ecological effects resulting from the implementation of a water pollution control program designed to eliminate direct discharges of wastewaters to EFPC and to minimize the inadvertent release of pollutants to the environment. Because of the complex nature of the discharges to EFPC and the temporal and spatial variability in the composition of the discharges, a comprehensive, integrated approach to biological monitoring was developed. A new permit was issued to the Y-12 Plant on April 28, 1995 and became effective on July 1, 1995. Biological monitoring continues to be required under the new permit. The BMAP consists of four major tasks that reflect different but complementary approaches to evaluating the effects of the Y-12 Plant discharges on the aquatic integrity …
Date: October 18, 2000
Creator: Adams, S. M.; Christensen, S. W.; Greeley, M. S. Jr; Hill, W. R.; McCarthy, J. F.; Peterson, M. J. et al.
Object Type: Report
System: The UNT Digital Library
The Development of Mobile Melt-Dilute Technology for the Treatment of Former Soviet Union Research Reactor Fuel (open access)

The Development of Mobile Melt-Dilute Technology for the Treatment of Former Soviet Union Research Reactor Fuel

On-site application of the MMD process offers an economical method for converting weapons usable Former Soviet Union (FSU) High Enriched Uranium (HEU) research reactor fuel to a safe and secure Low Enriched Uranium (LEU) ingot. The objective of the MMD Project is to develop the mobile melt and dilute technology in preparation for active equipment deployment in the Newly Independent States (NIS) of the FSU.
Date: October 9, 2003
Creator: Adams, T.
Object Type: Article
System: The UNT Digital Library