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The Use of Thyristors for Repetitive Narrow Pulse, High Power Switching

Description: Inverter type thyristors were switched repetitively to failure with 1 {micro}s pulses at repetition rates of 10, 50 and 100 pps and at peak currents up to 12 kA. Millions of pulses could be obtained before failure if the peak current were held at around 6 kA.
Date: January 13, 2000
Creator: Bayne, S. B.; Portnoy, W. M. & Rohwein, G. J.
Partner: UNT Libraries Government Documents Department
open access

Theory of Nanocluster Size Distributions from Ion Beam Synthesis

Description: Ion beam synthesis of nanoclusters is studied via both kinetic Monte Carlo simulations and the self-consistent mean-field solution to a set of coupled rate equations. Both approaches predict the existence of a steady state shape for the cluster size distribution that depends only on a characteristic length determined by the ratio of the effective diffusion coefficient to the ion flux. The average cluster size in the steady state regime is determined by the implanted species/matrix interface ene… more
Date: June 13, 2008
Creator: Yuan, C. W.; Yi, D. O.; Sharp, I. D.; Shin, S. J.; Liao, C. Y.; Guzman, J. et al.
Partner: UNT Libraries Government Documents Department
open access

Effect of pressure on the luminescence emissions in CuGaSe2

Description: We present the results of a pressure-dependent photoluminescence (PL) study on CuGaSe{sub 2} films grown on GaAs substrate by metalorganic vapor phase epitaxy. The low-temperature PL spectra of the CuGaSe{sub 2} samples measured at atmospheric pressure are dominated by one near band-edge exciton luminescence line and two strong and relatively broad emissions associated with donor acceptor pairs (DAP). All the observed luminescence emission lines shift toward higher energy with increasing pressu… more
Date: July 13, 2004
Creator: Shan, W.; Walukiewicz, W.; Wu, J.; Yu, K. M.; Ager, J. W., III; Siebentritt, S. et al.
Partner: UNT Libraries Government Documents Department
open access

Pressure-dependent photoluminescence study of ZnO nanowires

Description: The pressure dependence of the photoluminescence (PL) transition associated with the fundamental band gap of ZnO nanowires has been studied at pressures up to 15 GPa. ZnO nanowires are found to have a higher structural phase transition pressure around 12 GPa as compared to 9.0 GPa for bulk ZnO. The pressure-induced energy shift of the near band-edge luminescence emission yields a linear pressure coefficient of 29.6 meV/GPa with a small sublinear term of -0.43 meV/GPa{sup 2}. An effective hydros… more
Date: September 13, 2004
Creator: Shan, W.; Walukiewicz, W.; Ager, J. W., III; Yu, K. M.; Zhang, Y.; Mao, S. S. et al.
Partner: UNT Libraries Government Documents Department
open access

W and WSi(x) Ohmic Contacts on p- And n-Type GaN

Description: W and WSi ohmic contacts on both p- and n-type GaN have been annealed at temperatures from 300-1000 *C. There is minimal reaction (< 100 ~ broadening of the metal/GaN interface) even at 1000 *C. Specific contact resistances in the 10-5 f2-cm2 range are obtained for WSiX on Si-implanted GaN with a peak doping concentration of- 5 x 1020 cm-3, after annealing at 950 `C. On p-GaN, leaky Schottky diode behavior is observed for W, WSiX and Ni/Au contacts at room temperature, but true ohmic characteri… more
Date: October 13, 1998
Creator: Abernathy, C. R.; Cao, X. A.; Eizenberg, M.; Han, J.; Lothian, J. R.; Pearton, S. J. et al.
Partner: UNT Libraries Government Documents Department
open access

New Results with the superconducting ECR ion source VENUS

Description: During the last year, the VENUS ECR ion source was commissioned at 18 GHz and preparations for 28 GHz operation, which is set to begin early in 2004, are now underway. The goal of the VENUS ECR ion source project as the RIA R&amp;D injector is the production of 240emA of U30+, a high current medium charge state beam. On the other hand, as an injector ion source for the 88-Inch Cyclotron the design objective is the production of 5emA of U48+, a low current, very high charge state beam. During th… more
Date: May 13, 2004
Creator: Lyneis, C. M.; Leitner, D.; Abbott, S. R.; Dwinell, R. D.; Leitner, M.; Silver, C. S. et al.
Partner: UNT Libraries Government Documents Department
open access

[1/2 HP Maytag Restoration]

Description: Article by Pettinger, Wesley E. about 1/2 HP Maytag Engine Restoration.
Date: January 13, 1997
Creator: Pettinger, Wesley E.
Partner: UNT Libraries Special Collections
open access

Ideal plasticity and shape memory of nanolamellar high-entropy alloys

Description: Article describes how understanding the relationship among elemental compositions, nanolamellar microstructures, and mechanical properties enables the rational design of high-entropy alloys (HEAs). In this article the authors construct nanolamellar Alx-CoCuFeNi HEAs with alternating high- and low-Al concentration layers and explore their mechanical properties using a combination of molecular dynamic simulation and density functional theory calculation.
Date: October 13, 2023
Creator: Chen, Shuai; Liu, Ping; Pei, Qingxiang; Yu, Zhi Gen; Aitken, Zachary H.; Li, Wanghui et al.
Partner: UNT College of Engineering
open access

School counseling prevention programming to address social determinants of mental health

Description: Article describes how school counselors can utilize the Advocating Student-within-Environment (ASE) theoretical lens as a liberation approach to strengthening students' capacity to overcome persistent adversity while addressing root causes of systemic oppression through policy change and advocacy at the school, community, and national levels. This study provides school counselors with an overview of ASE as a theoretical foundation for addressing social determinants of mental health in schools.
Date: May 13, 2023
Creator: Johnson, Kaprea F.; Kim, Hyunhee; Molina, Citlali E.; Thompson, Kaleb A.; Henry, Sarah & Zyromski, Brett
Partner: UNT College of Education
open access

Using Machine Learning to Predict Genes Underlying Differentiation of Multipartite and Unipartite Traits in Bacteria

Description: Article describes how, since the discovery of the second chromosome in the Rhodobacter spaeroides 2.4.1 in 1989 and the revelation of gene sequences, multipartite genomes have been reported in over three hundred bacterial species under nine different phyla. In this study, the authors have attempted to leverage machine learning as a means to identify the genetic factors that underlie the differentiation of bacteria with multipartite and unipartite genomes.
Date: November 13, 2023
Creator: Almalki, Fatemah; Sunuwar, Janak & Azad, Rajeev K.
Partner: UNT College of Science
open access

DEVELOPMENTS IN THE MEASUREMENT OF ACTINIDES AND129I AT LLNL BY ACCELERATOR MASS SPECTROMETRY

Description: The application of ultra-sensitive heavy isotope measurements continues to expand in a variety of fields relevant to the management of nuclear materials, including nuclear isotope forensics and radiobioassay. We have developed a heavy isotope accelerator mass spectrometry (AMS) system at Lawrence Livermore National Laboratory's (LLNL) Center for Accelerator Mass Spectrometry (CAMS). The system was designed particularly for the measurement of actinide concentrations and isotopic ratios, but also… more
Date: January 13, 2005
Creator: Brown, T. A.; Marchetti, A. A.; Weyhenmeyer, C. E.; Knezovich, J. P.; Hamilton, T. F. & Nimz, G. J.
Partner: UNT Libraries Government Documents Department
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