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DiMES Studies of Temperature Dependence of Carbon Erosion and Re-Deposition in the DIII-D Divertor (open access)

DiMES Studies of Temperature Dependence of Carbon Erosion and Re-Deposition in the DIII-D Divertor

A strong effect of a moderately elevated surface temperature on net carbon deposition and deuterium co-deposition in the DIII-D divertor was observed under detached conditions. A DiMES sample with a gap 2 mm wide and 18 mm deep was exposed to lower-single-null (LSN) L-mode plasmas first at room temperature, and then at 200 C. At the elevated temperature, deuterium co-deposition in the gap was reduced by an order of magnitude. At the plasma-facing surface of the heated sample net carbon erosion was measured at a rate of 3 nm/s, whereas without heating net deposition is normally observed under detachment. In a related experiment three sets of molybdenum mirrors recessed 2 cm below the divertor floor were exposed to identical LSN ELMy H-mode discharges. The first set of mirrors exposed at ambient temperature exhibited net carbon deposition at a rate of up to 3.7 nm/s and suffered a significant drop in reflectivity. In contrast, two other mirror sets exposed at elevated temperatures between 90 C and 175 C exhibited virtually no carbon deposition.
Date: October 2, 2006
Creator: Rudakov, D.; Jacob, W.; Krieger, K.; Litnovsky, A.; Philipps, V.; West, W. et al.
Object Type: Article
System: The UNT Digital Library
Toward a Mesoscale Model for the Dynamics of Polymer Solutions (open access)

Toward a Mesoscale Model for the Dynamics of Polymer Solutions

To model entire microfluidic systems containing solvated polymers we argue that it is necessary to have a numerical stability constraint governed only by the advective CFL condition. Advancements in the treatment of Kramers bead-rod polymer models are presented to enable tightly-coupled fluid-particle algorithms in the context of system-level modeling.
Date: October 2, 2006
Creator: Miller, G H & Trebotich, D
Object Type: Article
System: The UNT Digital Library
Olivine-FeS Partial-Melt (open access)

Olivine-FeS Partial-Melt

The figure shows Fe-S-filled melt channels in olivine created at high temperature and pressure. The 3D image was obtained on Beamline 8.3.2 at the Advanced Light Source, Lawrence Berkeley Laboratory, with a spatial resolution of better than two microns (bar is 10 microns). Permeability of Fe-S melts in olivine at high temperatures and pressures provides an important constraint on models of planetary core formation. Permeability must be inferred from empirical relationships based on microstructure. To date, estimates of permeability have varied by more than five orders of magnitude. To provide more accurate constraints, we used high-resolution synchrotron radiation computed tomography to image the three-dimensional network of melt-containing pores in an olivine matrix, and calculated the permeability directly by solving the equations of Stokes flow through the actual pore network using a lattice-Boltzmann approach. These calculations provide an independent constraint on models of planetary core formation.
Date: October 2, 2006
Creator: Roberts, J.; Siebert, J.; Ryerson, F. J. & Kinney, J.
Object Type: Article
System: The UNT Digital Library
RHIC Performance with polarized protons in run-6 (open access)

RHIC Performance with polarized protons in run-6

In this study, an array of vibration measurements at the undisturbed NSLS II site has been performed in order to establish the 'green-field' vibration environment and its spectral characteristics. The interaction of the green-field vibration environment with the NSLS II accelerator structure and the quantification of the storage ring vibration, both in terms of amplitude and spectral content have been assessed through a state-of-the-art wave propagation and scattering analysis. This paper focuses on the wave propagation and scattering aspect as well as on the filtering effects of accelerator structural parameters.
Date: October 2, 2006
Creator: Ptitsyn, V.; Ahrens, L.; Bai, M.; Beebe-Wang, J.; Blaskiewicz, M.; Bravar, S. et al.
Object Type: Article
System: The UNT Digital Library
TDNA Monthly Office Manager's Report: September 2006 (open access)

TDNA Monthly Office Manager's Report: September 2006

Monthly report written by the Texas Daily Newspaper Association's (TDNA's) office manager, Darla Thompson, to Ken Whalen providing a summary of revenues and account balances, programs, meetings, and other activities in the office during the previous month.
Date: October 2, 2006
Creator: Thompson, Darla
Object Type: Report
System: The UNT Digital Library
Lame Duck Sessions of Congress, 1935-2004 (74th-108th Congresses) (open access)

Lame Duck Sessions of Congress, 1935-2004 (74th-108th Congresses)

None
Date: October 2, 2006
Creator: unknown
Object Type: Report
System: The UNT Digital Library
[Letter from Ken Whalen to Jeremy L. Halbreich, October 2, 2006] (open access)

[Letter from Ken Whalen to Jeremy L. Halbreich, October 2, 2006]

Letter from Ken Whalen to Jeremy L. Halbreich on October 2, 2006 with the subject 2007 Board Elections. The letter is in regards to the beginnings of the TDNA board of directors nomination process with enclosed information and review timetable schedule detailing the procedure process. Whalen states that Halbreich has the responsibility to naming the nomination committee and has included a list of committees since 1990.
Date: October 2, 2006
Creator: Whalen, Ken
Object Type: Letter
System: The UNT Digital Library
HIGH LEVEL WASTE SLUDGE BATCH 4 VARIABILITY STUDY (open access)

HIGH LEVEL WASTE SLUDGE BATCH 4 VARIABILITY STUDY

The Defense Waste Processing Facility (DWPF) is preparing for vitrification of High Level Waste (HLW) Sludge Batch 4 (SB4) in early FY2007. To support this process, the Savannah River National Laboratory (SRNL) has provided a recommendation to utilize Frit 503 for vitrifying this sludge batch, based on the composition projection provided by the Liquid Waste Organization on June 22, 2006. Frit 418 was also recommended for possible use during the transition from SB3 to SB4. A critical step in the SB4 qualification process is to demonstrate the applicability of the durability models, which are used as part of the DWPF's process control strategy, to the glass system of interest via a variability study. A variability study is an experimentally-driven assessment of the predictability and acceptability of the quality of the vitrified waste product that is anticipated from the processing of a sludge batch. At the DWPF, the durability of the vitrified waste product is not directly measured. Instead, the durability is predicted using a set of models that relate the Product Consistency Test (PCT) response of a glass to the chemical composition of that glass. In addition, a glass sample is taken during the processing of that sludge batch, the …
Date: October 2, 2006
Creator: Fox, K; Tommy Edwards, T; David Peeler, D; David Best, D; Irene Reamer, I & Phyllis Workman, P
Object Type: Report
System: The UNT Digital Library
SINGLE-TRANSVERSE SPIN ASYMMETRIES (open access)

SINGLE-TRANSVERSE SPIN ASYMMETRIES

We give a brief overview of some of the recent results on single-transverse spin asymmetries, highlighting in particular progress in theoretical understanding.
Date: October 2, 2006
Creator: VOGELSANG, W.
Object Type: Article
System: The UNT Digital Library
ACCELERATING POLARIZED PROTONS TO HIGH ENERGY. (open access)

ACCELERATING POLARIZED PROTONS TO HIGH ENERGY.

The Relativistic Heavy Ion Collider (RHIC) is designed to provide collisions of high energy polarized protons for the quest of understanding the proton spin structure. Polarized proton collisions at a beam energy of 100 GeV have been achieved in RHIC since 2001. Recently, polarized proton beam was accelerated to 250 GeV in RHIC for the first time. Unlike accelerating unpolarized protons, the challenge for achieving high energy polarized protons is to fight the various mechanisms in an accelerator that can lead to partial or total polarization loss due to the interaction of the spin vector with the magnetic fields. We report on the progress of the RHIC polarized proton program. We also present the strategies of how to preserve the polarization through the entire acceleration chain, i.e. a 200 MeV linear accelerator, the Booster, the AGS and RHIC.
Date: October 2, 2006
Creator: Bai, M.; Ahrens, L.; Alekseev, I. G.; Alessi, J.; Beebe-Wang, J.; Blaskiewicz, M. et al.
Object Type: Article
System: The UNT Digital Library
ENDF/B-VII.0: Next Generation Evaluated Nuclear Data Library for Nuclear Science and Technology (open access)

ENDF/B-VII.0: Next Generation Evaluated Nuclear Data Library for Nuclear Science and Technology

We describe the next generation general purpose Evaluated Nuclear Data File, ENDF/B-VII.0, of recommended nuclear data for advanced nuclear science and technology applications. The library, released by the U.S. Cross Section Evaluation Working Group (CSEWG) in December 2006, contains data primarily for reactions with incident neutrons, protons, and photons on almost 400 isotopes. The new evaluations are based on both experimental data and nuclear reaction theory predictions. The principal advances over the previous ENDF/B-VI library are the following: (1) New cross sections for U, Pu, Th, Np and Am actinide isotopes, with improved performance in integral validation criticality and neutron transmission benchmark tests; (2) More precise standard cross sections for neutron reactions on H, {sup 6}Li, {sup 10}B, Au and for {sup 235,238}U fission, developed by a collaboration with the IAEA and the OECD/NEA Working Party on Evaluation Cooperation (WPEC); (3) Improved thermal neutron scattering; (4) An extensive set of neutron cross sections on fission products developed through a WPEC collaboration; (5) A large suite of photonuclear reactions; (6) Extension of many neutron- and proton-induced reactions up to an energy of 150 MeV; (7) Many new light nucleus neutron and proton reactions; (8) Post-fission beta-delayed photon decay spectra; (9) New …
Date: October 2, 2006
Creator: Chadwick, M. B.; Oblozinsky, P.; Herman, M.; Greene, N. M.; McKnight, R. D.; Smith, D. L. et al.
Object Type: Article
System: The UNT Digital Library
THRESHOLD RESUMMATION EFFECTS IN THE POLARIZED DRELL-YAN MECHANISM. (open access)

THRESHOLD RESUMMATION EFFECTS IN THE POLARIZED DRELL-YAN MECHANISM.

We present theoretical predictions for the cross sections and spin asymmetries in dilepton pair production in transversely polarized pp and {bar p}p collisions. We use the available fixed-order corrections as well as the all-order resummation of threshold logarithms for the pair mass and rapidity distributions. Numerical results for pp collisions at {radical}s = 10 GeV at J-PARC and for {bar p}p collisions at {radical}s = 14.5 GeV at GSI-PAX are given.
Date: October 2, 2006
Creator: YOKOYA, H. & VOGELSANG, W.
Object Type: Article
System: The UNT Digital Library
INL Sitewide Operations and Maintenance Report for CERCLA Response Actions - FY2006 (open access)

INL Sitewide Operations and Maintenance Report for CERCLA Response Actions - FY2006

This report documents how remedies mandated by the Comprehensive Environmental Response, Compensation, and Liability Act for the Idaho National Laboratory Site were operated and maintained during Fiscal Year 2006. The activities addressed in the INEEL Sitewide Operations and Maintenance Plan are reported in this document.
Date: October 2, 2006
Creator: Olaveson, B. E.
Object Type: Report
System: The UNT Digital Library
Development of Front Surface, Spectral Control Filters with Greater Temperature Stability for Thermophotovoltaic Energy Conversion (open access)

Development of Front Surface, Spectral Control Filters with Greater Temperature Stability for Thermophotovoltaic Energy Conversion

Spectral control is an important consideration in achieving high conversion efficiency with thermophotovoltaic (TPV) energy conversion systems. TPV modules using front surface filters as the primary spectral control device have demonstrated conversion efficiencies in excess of 20% with power densities in excess of 0.4 W/cm{sup 2}. The front surface filter we are developing is a short pass, long wavelength reflection filter consisting of an interference filter deposited on a plasma filter. The materials used in the interference filter must exhibit high broad band transmission and good film quality and sufficient temperature stability at the operating temperature of the TPV cells and over any potential temperature excursions that may occur. Three high refractive index materials that offer good potential for use in TPV spectral control filters are antimony selenide (Sb{sub 2}Se{sub 3}), antimony sulfide (Sb{sub 2}S{sub 3}), and gallium telluride (GaTe). The highest spectral efficiency has been demonstrated using Sb{sub 2}Se{sub 3}; however this material develops significant near infrared (NIR, 0.72-2.5 {micro}m) absorption at temperatures in excess of 90 C. The other two materials are being developed as high temperature alternatives to Sb{sub 2}Se{sub 3}. TPV filters using GaTe and Sb{sub 2}S{sub 3} have been designed and fabricated, and initial results …
Date: October 2, 2006
Creator: TD Rahmlow, Jr.; DePoy, DM; Fourspring, PM; Ehsani, H; Lazo-Wasem, JE & Gratiix, EJ
Object Type: Article
System: The UNT Digital Library
Nucleon Structure in Lattice Qcd With Dynamical Domain--Wall Fermions Quarks. (open access)

Nucleon Structure in Lattice Qcd With Dynamical Domain--Wall Fermions Quarks.

We report RBC and RBC/UKQCD lattice QCD numerical calculations of nucleon electroweak matrix elements with dynamical domain-wall fermions (DWF) quarks. The first, RBC, set of dynamical DWF ensembles employs two degenerate flavors of DWF quarks and the DBW2 gauge action. Three sea quark mass values of 0.04, 0.03 and 0.02 in lattice units are used with 220 gauge configurations each. The lattice cutoff is a{sup -1} {approx} 1.7GeV and the spatial volume is about (1.9fm){sup 3}. Despite the small volume, the ratio of the isovector vector and axial charges g{sub A}/g{sub V} and that of structure function moments <x>{sub u-d}/<x>{sub {Delta}u-{Delta}d} are in agreement with experiment, and show only very mild quark mass dependence. The second, RBC/UK, set of ensembles employs one strange and two degenerate (up and down) dynamical DWF quarks and Iwasaki gauge action. The strange quark mass is set at 0.04, and three up/down mass values of 0.03, 0.02 and 0.01 in lattice units are used. The lattice cutoff is a{sup -1} {approx} 1.6GeV and the spatial volume is about (3.0fm){sup 3}. Even with preliminary statistics of 25-30 gauge configurations, the ratios g{sub A}/g{sub V} and <x>{sub u-d}/<x>{sub {Delta}u-{Delta}d} are consistent with experiment and show only very …
Date: October 2, 2006
Creator: Lin, H. W. & Ohta, S.
Object Type: Article
System: The UNT Digital Library
Cathodic Vacuum Arc Plasma of Thallium (open access)

Cathodic Vacuum Arc Plasma of Thallium

Thallium arc plasma was investigated in a vacuum arc ionsource. As expected from previous consideration of cathode materials inthe Periodic Table of the Elements, thallium plasma shows lead-likebehavior. Its mean ion charge state exceeds 2.0 immediately after arctriggering, reaches the predicted 1.60 and 1.45 after about 100 microsecand 150 microsec, respectively. The most likely ion velocity is initially8000 m/s and decays to 6500 m/s and 6200 m/s after 100 microsec and 150microsec, respectively. Both ion charge states and ion velocities decayfurther towards steady state values, which are not reached within the 300microsec pulses used here. It is argued that the exceptionally high vaporpressure and charge exchange reactions are associated with theestablishment of steady state ion values.
Date: October 2, 2006
Creator: Yushkov, Georgy Yu. & Anders, Andre
Object Type: Article
System: The UNT Digital Library
THE FUTURE OF SPIN PHYSICS AT BNL. (open access)

THE FUTURE OF SPIN PHYSICS AT BNL.

The Relativistic Heavy Ion Collider (RHIC) at BNL is the world's only polarized proton-proton collider. Collisions at center-of-mass energies up to 500 GeV and beam polarizations approaching 70% (longitudinal or transverse) are provided to two experiments, STAR and PHENIX, at luminosities {ge} 10{sup 32}/cm{sup 2}/sec. Transverse polarized beam has also been provided to the BRAHMS experiment. Measurements that bear on the important question of the spin content of the nucleon are beginning to appear. Over the next 10 years, as the performance of polarized proton running at RHIC is further developed, the Spin Physics program at RHIC will provide definitive measurements of the contributions to the proton's spin of the gluon, the sea quarks and the orbital motion of the partons in the proton's wave function. We plan to extend the reach of our study of the role of spin in QCD with the development of ''eRHIC'', which will provide polarized e-p collisions to a new detector.
Date: October 2, 2006
Creator: ARONSON, S. & DESHPANDE, A.
Object Type: Article
System: The UNT Digital Library
A Study of Polarized Proton Acceleration in J-Parc. (open access)

A Study of Polarized Proton Acceleration in J-Parc.

We have studied the feasibility of polarized proton acceleration in rhe J-PARC accelerator facility, consisting of a 400 MeV linac, a 3 GeV rapid cycling synchrotron (RCS) and a 50 GeV synchrotron (MR). We show how the polarization of the beam can be preserved using an rf dipole in the RCS and two superconductive partial helical Siberian snakes in the MR. The lattice of the MR will be modified with the addition of quadrupoles to compensate for the focusing properties of the snakes.
Date: October 2, 2006
Creator: Luccio, A. U.; Bai, M. & Roser, T.
Object Type: Article
System: The UNT Digital Library
Studies of electron and proton isochoric heating for fast ignition (open access)

Studies of electron and proton isochoric heating for fast ignition

Isochoric heating of inertially confined fusion plasmas by laser driven MeV electrons or protons is an area of great topical interest in the inertial confinement fusion community, particularly with respect to the fast ignition (FI) proposal to use this technique to initiate burn in a fusion capsule. Experiments designed to investigate electron isochoric heating have measured heating in two limiting cases of interest to fast ignition, small planar foils and hollow cones. Data from Cu K{alpha} fluorescence, crystal x-ray spectroscopy of Cu K shell emission, and XUV imaging at 68eV and 256 eV are used to test PIC and Hybrid PIC modeling of the interaction. Isochoric heating by focused proton beams generated at the concave inside surface of a hemi-shell and from a sub hemi-shell inside a cone have been studied with the same diagnostic methods plus imaging of proton induced K{alpha}. Conversion efficiency to protons has also been measured and modeled. Conclusions from the proton and electron heating experiments will be presented. Recent advances in modeling electron transport and innovative target designs for reducing igniter energy and increasing gain curves will also be discussed.
Date: October 2, 2006
Creator: Mackinnon, A.; Key, M.; Akli, K.; Beg, F.; Clarke, R.; Clarke, D. et al.
Object Type: Article
System: The UNT Digital Library
Finding General Explicit Formulas for Ising Integral Recursions (open access)

Finding General Explicit Formulas for Ising Integral Recursions

None
Date: October 2, 2006
Creator: Bailey, D. H. & Borwein, J. M.
Object Type: Report
System: The UNT Digital Library
Multilayer Defects Nucleated by Substrate Pits: A Comparison of Actinic Inspection and Non-Actinic Inspection Techniques (open access)

Multilayer Defects Nucleated by Substrate Pits: A Comparison of Actinic Inspection and Non-Actinic Inspection Techniques

The production of defect-free mask blanks remains a key challenge for EUV lithography. Mask-blank inspection tools must be able to accurately detect all critical defects while simultaneously having the minimum possible false-positive detection rate. We have recently observed and here report the identification of bump-type buried substrate defects, that were below the detection limit of a non-actinic (i.e. non-EUV) in inspection tool. Presently, the occurrence inspection of pit-type defects, their printability, and their detectability with actinic techniques and non-actinic commercial tools, has become a significant concern. We believe that the most successful strategy for the development of effective non-actinic mask inspection tools will involve the careful cross-correlation with actinic inspection and lithographic printing. In this way, the true efficacy of prototype inspection tools now under development can be studied quantitatively against relevant benchmarks. To this end we have developed a dual-mode actinic mask inspection system capable of scanning mask blanks for defects (with simultaneous EUV bright-field and dark-field detection) and imaging those same defects with a zoneplate microscope that matches or exceeds the resolution of EUV steppers.
Date: October 2, 2006
Creator: Barty, A.; Goldberg, K.; Kearney, P.; Rekawa, S.; LaFontaine, B.; Wood, O. et al.
Object Type: Article
System: The UNT Digital Library
The International Space Station and the Space Shuttle (open access)

The International Space Station and the Space Shuttle

This report provides an overview of the international space station and the space shuttle.
Date: October 2, 2006
Creator: Behrens, Carl E.
Object Type: Report
System: The UNT Digital Library
The Baytown Sun (Baytown, Tex.), Vol. 85, No. 312, Ed. 1 Monday, October 2, 2006 (open access)

The Baytown Sun (Baytown, Tex.), Vol. 85, No. 312, Ed. 1 Monday, October 2, 2006

Daily newspaper from Baytown, Texas that includes local, state, and national news along with advertising.
Date: October 2, 2006
Creator: Clements, Clifford E.
Object Type: Newspaper
System: The Portal to Texas History
[Funeral Program for Willie Tatum Carter, October 2, 2006] (open access)

[Funeral Program for Willie Tatum Carter, October 2, 2006]

Funeral program for Willie T. Tatum Carter, died September 2006. The funeral was held October 2, 2006 at Friendship Missionary Baptist Church, officiated by Rev. R. L. Archield, Sr. The funeral arrangements were made through Lewis Funeral Home and she was buried in Fort Sam Houston National Cemetery near San Antonio, Texas.
Date: October 2, 2006
Creator: unknown
Object Type: Pamphlet
System: The Portal to Texas History