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Ensemble and Guest Artist: 2003-11-25 One O'Clock Lab Band and Jimmy Heath, saxophone

Access: Use of this item is restricted to the UNT Community
Ensemble and Guest Artist: 2003-11-25-One O'Clock Lab Band and Jimmy Heath, saxophone A guest artist concert preformed at the UNT College of Music Winspear Hall.
Date: November 25, 2003
Creator: One O'Clock Lab Band
Object Type: Sound
System: The UNT Digital Library
Veterans Affairs: Post-hearing Questions Regarding the Departments of Defense and Veterans Affairs Providing Seamless Health Care Coverage to Transitioning Veterans (open access)

Veterans Affairs: Post-hearing Questions Regarding the Departments of Defense and Veterans Affairs Providing Seamless Health Care Coverage to Transitioning Veterans

Correspondence issued by the General Accounting Office with an abstract that begins "The Ranking Minority Member of the House Committee on Veterans Affairs requested that GAO respond to follow-up questions on its testimony on its report "Hand-off or Fumble: Are DOD and VA Providing Seamless Health Care Coverage to Transitioning Veterans?""
Date: November 25, 2003
Creator: United States. General Accounting Office.
Object Type: Text
System: The UNT Digital Library
Multi-fluid code simulations including anomalous non-diffusive transport of plasma and impurities in the tokamak SOL (open access)

Multi-fluid code simulations including anomalous non-diffusive transport of plasma and impurities in the tokamak SOL

Fast intermittent transport has been observed in the scrape-off layer (SOL) of major tokamaks including Alcator C-Mod, DIII-D, and NSTX. This kind of transport is not diffusive but rather convective. It strongly increases plasma flux to the chamber walls and enhances the recycling of neutral particles in the main chamber. We discuss anomalous cross-field convection (ACFC) model for impurity and main plasma ions and its relation to intermittent transport events, i.e. plasma density blobs and holes in the SOL. Along with plasma diffusivity coefficients, our transport model introduces time-independent anomalous cross-field convective velocity. In the discharge modelling, diffusivity coefficients and ACFC velocity profiles are adjusted to match a set of representative experimental data. We use this model in the edge plasma physics code UEDGE to simulate the multi-fluid two-dimensional transport for these three tokamaks. We present simulation results suggesting the dominance of anomalous convection in the far SOL transport. These results are consistent with the hypothesis that the chamber wall is an important source of impurities and that different impurity charge states have different directions of anomalous convective velocity.
Date: November 25, 2003
Creator: Pigarov, A. Yu; West, W. P.; Soukhanovskii, V.; Rognlien, T. D.; Maingi, R.; Lipschultz, B. et al.
Object Type: Article
System: The UNT Digital Library
Texas Attorney General Opinion: GA-125 (open access)

Texas Attorney General Opinion: GA-125

Document issued by the Office of the Attorney General of Texas in Austin, Texas, providing an interpretation of Texas law. It provides the opinion of the Texas Attorney General, Greg Abbott, regarding a legal question submitted for clarification: Whether a minor may be classified as a “missing child” under article 63.001, Code of Criminal Procedure, if the minor’s legal custodian knows the minor’s whereabouts (RQ-0057-GA)
Date: November 25, 2003
Creator: Texas. Attorney-General's Office.
Object Type: Text
System: The Portal to Texas History
Energy Policy: The Continuing Debate and Omnibus Energy Legislation (H.R. 6) (open access)

Energy Policy: The Continuing Debate and Omnibus Energy Legislation (H.R. 6)

This report includes background and analysis on the debate on energy policy, as well as Omnibus energy legislation. Electricity restructuring, nuclear energy, and renewable energy and fuels are among topics discussed in this report.
Date: November 25, 2003
Creator: Bamberger, Robert L.
Object Type: Report
System: The UNT Digital Library
Monitoring Plan for RCRA Groundwater Assessment at the 216-U-12 Crib, Interim Change Notice 1 (open access)

Monitoring Plan for RCRA Groundwater Assessment at the 216-U-12 Crib, Interim Change Notice 1

This ICN corrects a typing error that was identified for one of the wells listed in Tables 4.1 and 4.2 on page 4.3 of the original document.
Date: November 25, 2003
Creator: Williams, Bruce A.
Object Type: Report
System: The UNT Digital Library
Coherence Measurements of a Transient 14.7 nm X-ray Laser (open access)

Coherence Measurements of a Transient 14.7 nm X-ray Laser

We present the longitudinal coherence measurement of the transient inversion collisional x-ray laser for the first time. The Ni-like Pd x-ray laser at 14.68 nm is generated by the LLNL COMET laser facility and is operating in the gain-saturated regime. Interference fringes are produced using a Michelson interferometer setup in which a thin multilayer-coated membrane is used as a beam splitter. The longitudinal coherence length for the picosecond duration 4d{sup 1}S{sub 0} {yields} 4p{sup 1}P{sub 1} lasing transition is determined to be {approx}400 {micro}m (1/e HW) by adjusting the length of one interferometer arm and measuring the resultant variation in fringe visibility. This is four times improved coherence than previous measurements on quasi-steady state schemes largely as a result of the narrower line profile in the lower temperature plasma. The inferred gain-narrowed linewidth of {approx}0.29 pm is also substantially narrower than previous measurements on quasi-steady state x-ray laser schemes. This study shows that the coherence of the x-ray laser beam can be improved by changing the laser pumping conditions. The x-ray laser is operating at 4 - 5 times the transform-limited pulse.
Date: November 25, 2003
Creator: Remond, C; Dunn, J; Delmotte, F; Nilsen, J; Hubert, S; Ravet, M et al.
Object Type: Article
System: The UNT Digital Library
Cooper pair formation dynamics in Bi2Sr2CaCu2O8+delta (open access)

Cooper pair formation dynamics in Bi2Sr2CaCu2O8+delta

We utilize ultrafast terahertz pulses to monitor the carrierdynamics in the high-TC superconductor Bi2Sr2CaCu2O8+delta. Thetemperature, density and timedependence distinctly exposes a bimolecularrecombination process of quasiparticles which underlies formation ofCooper pairs.
Date: November 25, 2003
Creator: Kaindl, R. A.; Carnahan, M. A.; Orenstein, J.; Chemla, D. S.; Oh, S. & Eckstein, J. N.
Object Type: Article
System: The UNT Digital Library
[News Clip: Fake Drugs] captions transcript

[News Clip: Fake Drugs]

Video footage from the KXAS-TV/NBC station in Fort Worth, Texas, to accompany a news story.
Date: November 25, 2003
Creator: NBC 5 (Television station : Fort Worth, Tex.)
Object Type: Video
System: The UNT Digital Library
[News Clip: Fake Drugs] captions transcript

[News Clip: Fake Drugs]

Video footage from the KXAS-TV/NBC station in Fort Worth, Texas, to accompany a news story.
Date: November 25, 2003
Creator: NBC 5 (Television station : Fort Worth, Tex.)
Object Type: Video
System: The UNT Digital Library
Comparison of LiFePO4 from different sources (open access)

Comparison of LiFePO4 from different sources

The lithium iron phosphate chemistry is plagued by the poor conductivity and slow lithium diffusion in the solid phase. In order to alleviate these problems, various research groups have adopted different strategies including decreasing the particle sizes, increasing the carbon content, and adding dopants. In this study we obtained LiFePO4 electrodes from six different sources and used a combined model-experimental approach to compare the performance. Samples ranged from one with no carbon coating to one with 15 percent coating. In addition, particle sizes varied by as much as a order of magnitude between samples. The study detailed in this manuscript allows us to provide insight into the relative importance of the conductivity of the samples compared to the particle size, the impact of dopant on performance and ideas for making materials in order to maximize the power capability of this chemistry.
Date: November 25, 2003
Creator: Striebel, Kathryn; Shim, Joongpyo; Srinivasan, Venkat & Newman, John
Object Type: Article
System: The UNT Digital Library
Characterization of high-power lithium-ion cells-performance and diagnostic analysis (open access)

Characterization of high-power lithium-ion cells-performance and diagnostic analysis

Lithium-ion cells, with graphite anodes and LiNi0.8Co0.15Al0.05O2 cathodes, were cycled for up to 1000 cycles over different ranges of SOC and temperatures. The decline in cell performance increases with the span of SOC and temperature during cycling. Capacity fade was caused by a combination of the loss of cycleable Li and degradation of the cathode. The room temperature anodes showed SEI compositions and degrees of graphite disorder that correlated with the extent of the Li consumption, which was linear in cell test time. TEM of the cathodes showed evidence of crystalline defects, though no major new phases were identified, consistent with XRD. No evidence of polymeric deposits on the cathode particles (FTIR) was detected although both Raman and TEM showed evidence of P-containing deposits from electrolyte salt degradation. Raman microscopy showed differences in relative carbon contents of the cycled cathodes, which is blamed for part of the cathode degradation.
Date: November 25, 2003
Creator: Striebel, K. A.; Shim, J.; Kostecki, R.; Richardson, T. J.; Ross, P. N.; Song, X. et al.
Object Type: Article
System: The UNT Digital Library
Electron beam conditioning by Thomson scattering (open access)

Electron beam conditioning by Thomson scattering

A method is proposed for conditioning electron beams via Thomson scattering. The conditioning provides a quadratic correlation between the electron energy deviation and the betatron amplitude of the electrons, which results in enhanced gain in free-electron lasers. Quantum effects imply conditioning must occur at high laser fluence and moderate electron energy. Conditioning of x-ray free-electron lasers should be achievable with present laser technology, leading to significant size and cost reductions of these large-scale facilities.
Date: November 25, 2003
Creator: Schroeder, C. B.; Esarey, E. & Leemans, W. P.
Object Type: Article
System: The UNT Digital Library
Atomic structure of defects in GaN:Mg grown with Ga polarity (open access)

Atomic structure of defects in GaN:Mg grown with Ga polarity

Abstract: Electron microscope phase images, produced by direct reconstruction of the scattered electron wave from a focal series of high-resolution images, were used to determine the nature of defects formed in GaN:Mg crystals. We studied bulk crystals grown from dilute solutions of atomic nitrogen in liquid gallium at high pressure and thin films grown by the MOCVD method. All the crystals were grown with Ga-polarity. In both types of samples the majority of defects were three dimensional Mg-rich hexagonal pyramids with bases on the (0001) plane and six walls on {l_brace}11{und 2}3{r_brace} planes seen in cross-section as triangulars. Some other defects appear in cross-section as trapezoidal (rectangular) defects as a result of presence of truncated pyramids. Both type of defects have hollow centers. They are decorated by Mg on all six side walls and a base. The GaN which grows inside on the defect walls shows polarity inversion. It is shown that change of polarity starts from the defect tip and propagates to the base, and that the stacking sequence changes from ab in the matrix to bc inside the defect. Exchange of the Ga sublattice with the N sublattice within the defect leads to 0.6 {+-} 0.2{angstrom} displacement between …
Date: November 25, 2003
Creator: Liliental-Weber, Z.; Tomaszewicz, T.; Zakharov, D.; Jasinski, J.; O'Keefe, M. A.; Hautakangas, S. et al.
Object Type: Article
System: The UNT Digital Library
Kinetic Effects on the Stability Properties of Field-reversed Configurations: II. Nonlinear Evolution (open access)

Kinetic Effects on the Stability Properties of Field-reversed Configurations: II. Nonlinear Evolution

Results of three-dimensional hybrid simulations of the field-reversed configuration (FRC) are presented. Emphasis of this work is on the nonlinear evolution of magnetohydrodynamic (MHD) instabilities in kinetic FRCs. A wide range of ''bar s'' values is considered, where the ''bar s'' is the FRC kinetic parameter, which measures the number of ion gyroradii in the configuration. The linear and nonlinear stability of MHD modes with toroidal mode numbers n greater than or equal to 1 is investigated, including the effects of ion rotation, finite electron pressure, and weak toroidal field. Low-''bar s'' simulations show nonlinear saturation of the n = 1 tilt mode. The n greater than or equal to 2 rotational modes are observed to grow during the nonlinear phase of the tilt instability due to ion spin-up in the toroidal direction. Large-''bar s'' simulations show no saturation of the tilt mode, and there is a slow nonlinear evolution of the instability after the initial fast linear growth. Overall, the hybrid simulations demonstrate the importance of nonlinear effects, which are responsible for the saturation of instabilities in low-''bar s'' configurations, and also for the increase in FRC life-time compared to MHD models in high-''bar s'' configurations.
Date: November 25, 2003
Creator: Belova, Elena V.; Davidson, Ronald C.; Ji, Hantao & Yamada, Masaaki
Object Type: Report
System: The UNT Digital Library
Effect of conductive additives in LiFePO4 cathode for lithium-ion batteries (open access)

Effect of conductive additives in LiFePO4 cathode for lithium-ion batteries

The electrochemical properties of LiFePO4 cathodes with different carbon contents were studied to find out the role of carbon as conductive additive. LiFePO4 cathodes containing from 0 percent to 12 percent of conductive additive (carbon black or mixture of carbon black and graphite) were cycled at different C rates. The capacity of LiFePO4 cathode increased, as conductive additive content increased. Carbon increased the utilization of active material and the electrical conductivity of electrode, but decreased volumetric capacity of electrode.
Date: November 25, 2003
Creator: Shim, J.; Guerfi, A.; Zaghib, K. & Striebel, K.A.
Object Type: Article
System: The UNT Digital Library
The development of low cost LiFePO4-based high power lithium-ion batteries (open access)

The development of low cost LiFePO4-based high power lithium-ion batteries

The cycling performance of low-cost LiFePO4-based high-power lithium-ion cells was investigated and the components were analyzed after cycling to determine capacity fade mechanisms. Pouch type LiFePO4/natural graphite cells were assembled and evaluated by constant C/2 cycling, pulse-power and impedance measurements. From post-test electrochemical analysis after cycling, active materials, LiFePO4 and natural graphite, showed no degradation structurally or electrochemically. The main reasons for the capacity fade of cell were lithium inventory loss by side reaction and possible lithium deposition on the anode.
Date: November 25, 2003
Creator: Shim, Joongpyo; Sierra, Azucena & Striebel, Kathryn A.
Object Type: Article
System: The UNT Digital Library

[Historic Property, Photograph 4508-02]

Photograph of a historic property in Texas.
Date: November 25, 2003
Creator: Texas Historical Commission
Object Type: Photograph
System: The Portal to Texas History

[Pump House, (west façade view south)]

Photograph of the Pump House in Houston, Texas.
Date: November 25, 2003
Creator: Texas Historical Commission
Object Type: Photograph
System: The Portal to Texas History

[Pump House, (view south)]

Photograph of the Pump House in Houston, Texas.
Date: November 25, 2003
Creator: Texas Historical Commission
Object Type: Photograph
System: The Portal to Texas History

[Pump House, (view south)]

Photograph of the Pump House in Houston, Texas.
Date: November 25, 2003
Creator: Texas Historical Commission
Object Type: Photograph
System: The Portal to Texas History

[Incinerator]

Photograph of the Incinerator in Houston, Texas.
Date: November 25, 2003
Creator: Texas Historical Commission
Object Type: Photograph
System: The Portal to Texas History

[Storage Building, (view west)]

Photograph of the Storage Building in Houston, Texas.
Date: November 25, 2003
Creator: Texas Historical Commission
Object Type: Photograph
System: The Portal to Texas History
The Baytown Sun (Baytown, Tex.), Vol. 81, No. 358, Ed. 1 Tuesday, November 25, 2003 (open access)

The Baytown Sun (Baytown, Tex.), Vol. 81, No. 358, Ed. 1 Tuesday, November 25, 2003

Daily newspaper from Baytown, Texas that includes local, state, and national news along with advertising.
Date: November 25, 2003
Creator: Cash, Wanda Garner
Object Type: Newspaper
System: The Portal to Texas History