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Altus Times (Altus, Okla.), Vol. 105, No. 216, Ed. 1 Tuesday, November 25, 2003 (open access)

Altus Times (Altus, Okla.), Vol. 105, No. 216, Ed. 1 Tuesday, November 25, 2003

Daily newspaper from Altus, Oklahoma that includes local, state, and national news along with advertising.
Date: November 25, 2003
Creator: Andrews, Mike
Object Type: Newspaper
System: The Gateway to Oklahoma History
Analytical and Numerical Studies of the Complex Interaction of a Fast Ion Beam Pulse with a Background Plasma (open access)

Analytical and Numerical Studies of the Complex Interaction of a Fast Ion Beam Pulse with a Background Plasma

Plasma neutralization of an intense ion beam pulse is of interest for many applications, including plasma lenses, heavy ion fusion, high energy physics, etc. Comprehensive analytical, numerical, and experimental studies are underway to investigate the complex interaction of a fast ion beam with a background plasma. The positively charged ion beam attracts plasma electrons, and as a result the plasma electrons have a tendency to neutralize the beam charge and current. A suite of particle-in-cell codes has been developed to study the propagation of an ion beam pulse through the background plasma. For quasi-steady-state propagation of the ion beam pulse, an analytical theory has been developed using the assumption of long charge bunches and conservation of generalized vorticity. The analytical results agree well with the results of the numerical simulations. The visualization of the data obtained in the numerical simulations shows complex collective phenomena during beam entry into and ex it from the plasma.
Date: November 25, 2003
Creator: Kaganovich, Igor D.; Startsev, Edward A. & Davidson, Ronald C.
Object Type: Report
System: The UNT Digital Library
Aspect Ratio Scaling of Ideal No-wall Stability Limits in High Bootstrap Fraction Tokamak Plasmas (open access)

Aspect Ratio Scaling of Ideal No-wall Stability Limits in High Bootstrap Fraction Tokamak Plasmas

Recent experiments in the low aspect ratio National Spherical Torus Experiment (NSTX) [M. Ono et al., Nucl. Fusion 40 (2000) 557] have achieved normalized beta values twice the conventional tokamak limit at low internal inductance and with significant bootstrap current. These experimental results have motivated a computational re-examination of the plasma aspect ratio dependence of ideal no-wall magnetohydrodynamic stability limits. These calculations find that the profile-optimized no-wall stability limit in high bootstrap fraction regimes is well described by a nearly aspect ratio invariant normalized beta parameter utilizing the total magnetic field energy density inside the plasma. However, the scaling of normalized beta with internal inductance is found to be strongly aspect ratio dependent at sufficiently low aspect ratio. These calculations and detailed stability analyses of experimental equilibria indicate that the nonrotating plasma no-wall stability limit has been exceeded by as much as 30% in NSTX in a high bootstrap fraction regime.
Date: November 25, 2003
Creator: Menard, J. E.; Bell, M. G.; Bell, R. E.; Gates, D. A.; Kaye, S. M.; LeBlanc, B. P. et al.
Object Type: Report
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
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
The Boerne Star (Boerne, Tex.), Vol. 97, No. 95, Ed. 1 Tuesday, November 25, 2003 (open access)

The Boerne Star (Boerne, Tex.), Vol. 97, No. 95, Ed. 1 Tuesday, November 25, 2003

Semiweekly newspaper from Boerne, Texas that includes local, state, and national news along with advertising.
Date: November 25, 2003
Creator: Cartwright, Brian & Morgan, Clay
Object Type: Newspaper
System: The Portal to Texas History
Brady Standard-Herald and Heart O' Texas News (Brady, Tex.), Ed. 1 Tuesday, November 25, 2003 (open access)

Brady Standard-Herald and Heart O' Texas News (Brady, Tex.), Ed. 1 Tuesday, November 25, 2003

Semiweekly newspaper from Brady, Texas that includes local, state, and national news along with advertising.
Date: November 25, 2003
Creator: Stewart, James E.
Object Type: Newspaper
System: The Portal to Texas History
Cash and Noncash Benefits for Persons with Limited Income: Eligibility Rules, Recipient and Expenditure Data, FY2000-FY2002 (open access)

Cash and Noncash Benefits for Persons with Limited Income: Eligibility Rules, Recipient and Expenditure Data, FY2000-FY2002

This report provides basic eligibility rules, recipient numbers, and FY2000-FY2002 expenditure data for 80 programs that have provided cash or non-cash benefits to low-income persons.
Date: November 25, 2003
Creator: Burke, Vee
Object Type: Report
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
Clean Water Act: A Summary of the Law (open access)

Clean Water Act: A Summary of the Law

This report presents the Summary of the Clean Water Act Law describing the essence of the statute.
Date: November 25, 2003
Creator: Copeland, Claudia
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
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
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
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
Dislocation Image Stresses at Free Surfaces by the Finite Element Method (open access)

Dislocation Image Stresses at Free Surfaces by the Finite Element Method

The finite element method has been routinely used to calculate the image stresses of dislocation segments. When these segments intersect with surfaces, the image stresses at the surfaces diverges singularly. At the presence of these singularities, both convergence and accuracy of using the finite element method need to be examined critically. This article addresses these issues with the aim toward the application of dislocation dynamics simulations in thin films.
Date: November 25, 2003
Creator: Cai, W; Bulatov, V; Tang, M & Xu, G
Object Type: Article
System: The UNT Digital Library
East Central Europe: Status of International Criminal Court (ICC) Exemption Agreements and U.S. Military Assistance (open access)

East Central Europe: Status of International Criminal Court (ICC) Exemption Agreements and U.S. Military Assistance

In a broad effort to obtain U.S. exemptions from International Criminal Court (ICC) jurisdiction, the Bush Administration has sought to conclude bilateral agreements worldwide that would prohibit the transfer of U.S. citizens to the ICC. The European Union has strongly promoted the ICC and is opposed to the U.S.- proposed agreements. This report addresses twelve countries of east central Europe affected by the U.S. and European policies – Albania, Bosnia-Herzegovina, Bulgaria, Croatia, Estonia, Latvia, Lithuania, the former Yugoslav Republic of Macedonia, Romania, Serbia and Montenegro, Slovakia, and Slovenia – and the status of their varied approaches to the transatlantic disagreement over the ICC.
Date: November 25, 2003
Creator: Kim, Julie
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
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
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

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
Estimation of host rock thermal conductivities using thetemperature data from the drift-scale test at Yucca Mountain,Nevada (open access)

Estimation of host rock thermal conductivities using thetemperature data from the drift-scale test at Yucca Mountain,Nevada

A large volume of temperature data has been collected from a very large, underground heater test, the Drift Scale Test (DST) at Yucca Mountain, Nevada. The DST was designed to obtain thermal, hydrological, mechanical, and chemical (THMC) data in the unsaturated fractured rock of Yucca Mountain. Sophisticated numerical models have been developed to analyze the collected THMC data. In these analyses, thermal conductivities measured from core samples have been used as input parameters to the model. However, it was not known whether these core measurements represented the true field-scale thermal conductivity of the host rock. Realizing these difficulties, elaborate, computationally intensive geostatistical simulations have also been performed to obtain field-scale thermal conductivity of the host rock from the core measurements. In this paper, we use the temperature data from the DST as the input (instead of the measured core-scale thermal conductivity values) to develop an estimate of the field-scale thermal conductivity values. Assuming a conductive thermal regime, we develop an analytical solution for the temperature rise in the host rock of the DST; and using a nonlinear fitting routine, we obtain a best-fit estimate of field-scale thermal conductivity for the DST host rock. The temperature data collected from the DST …
Date: November 25, 2003
Creator: Mukhopadhyay, Sumitra & Tsang, Y. W.
Object Type: Article
System: The UNT Digital Library
The Express-Star (Chickasha, Okla.), Ed. 1 Tuesday, November 25, 2003 (open access)

The Express-Star (Chickasha, Okla.), Ed. 1 Tuesday, November 25, 2003

Daily newspaper from Chickasha, Oklahoma that includes local, state, and national news along with advertising.
Date: November 25, 2003
Creator: Bush, Kent
Object Type: Newspaper
System: The Gateway to Oklahoma History
Full-Scale Cookoff Model Validation Experiments (open access)

Full-Scale Cookoff Model Validation Experiments

This paper presents the experimental results of the third and final phase of a cookoff model validation effort. In this phase of the work, two generic Heavy Wall Penetrators (HWP) were tested in two heating orientations. Temperature and strain gage data were collected over the entire test period. Predictions for time and temperature of reaction were made prior to release of the live data. Predictions were comparable to the measured values and were highly dependent on the established boundary conditions. Both HWP tests failed at a weld located near the aft closure of the device. More than 90 percent of unreacted explosive was recovered in the end heated experiment and less than 30 percent recovered in the side heated test.
Date: November 25, 2003
Creator: McClelland, M. A.; Rattanapote, M. K.; Heimdahl, E. R.; Erikson, W. E.; Curran, P. O. & Atwood, A. I.
Object Type: Article
System: The UNT Digital Library
Groundwater Monitoring Plan for the 216-S-10 Pond and Ditch, Interim Change Notice 1 (open access)

Groundwater Monitoring Plan for the 216-S-10 Pond and Ditch, Interim Change Notice 1

During 2003, the upgradient well 299-W26-7 went dry and one new groundwater monitoring well was installed downgradient (well 299-W26-14) of the 216-S-10 pond and ditch. This ICN updates the groundwater monitoring wells for the 216-S-10 pond and ditch and adds a revised well location map to the plan.
Date: November 25, 2003
Creator: Williams, Bruce A.
Object Type: Report
System: The UNT Digital Library