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Conference paper

Description: Carbon Nanotubes as Transparent Electrodes, A case study in Organic Photovoltaics
Date: April 7, 2007
Creator: Glatkowski, Paul J.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

The LLNL Cluster Tool

Description: {lg_bullet} The Cluster Tool -is a set of linked vacuum chambers -can deposit multiple layers of metal and metal oxides {lg_bullet} Each layer can be deposited without breaking vacuum {lg_bullet} Shadow masks can give each layer a different pattern {lg_bullet} The Cluster Tool will be operational in April
Date: March 27, 2007
Creator: Hunter, S L
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

The effect of lattice temperature on surface damage in fused silica optics

Description: We examine the effect of lattice temperature on the probability of surface damage initiation for 355nm, 7ns laser pulses for surface temperatures below the melting point to temperatures well above the melting point of fused silica. At sufficiently high surface temperatures, damage thresholds are dramatically reduced. Our results indicate a temperature activated absorption and support the idea of a lattice temperature threshold of surface damage. From these measurements, we estimate the temperat… more
Date: October 31, 2007
Creator: Bude, J.; Guss, G.; Matthews, M. & Spaeth, M. L.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

DYNAMIC LOADING OF TEFLON AT 200?C

Description: Dynamic loading experiments were performed on inert Teflon (Polytetrafluoroethylene) samples, initially heated to the temperature of 200 C, to test its behavior under these conditions for its use in other heated experiments. Tests were performed in the 100 mm diameter bore propellant driven gas gun with piezo-resistive manganin pressure gauges imbedded into the samples to measure loading pressures. Experimental data provided new information on the shock velocity - particle velocity relationship… more
Date: June 13, 2007
Creator: Urtiew, P A; Forbes, J W; Tarver, C M; Vandersall, K S & Garcia, F
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

The energy coupling efficiency of multi-wavelength laser pulses to damage initiating defects in DKDP nonlinear crystals

Description: The bulk damage performance of potassium dihydrogen phosphate crystals under simultaneous exposure to 1064-, 532-, and 355-nm nanosecond-laser pulses is investigated in order to probe the laser-induced defect reactions leading to damage initiation during frequency conversion. The results provide insight into the mechanisms governing the behavior of the damage initiating defects under exposure to high power laser light. In addition, it is suggested that the damage performance can be directly rel… more
Date: September 25, 2007
Creator: DeMange, P; Negres, R A; Rubenchik, A M; Radousky, H B; Feit, M D & Demos, S G
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Elimination or Minimization of Oscillation Marks: A Path To Improved Cast Surface Quality

Description: Oscillation marks are the most recognizable feature of continuous casting and can be related to the subsurface defects that can be found on product rolled from continuous cast slabs. The purpose of this work was to develop strategies that can be used on industrial continuous casters to reduce oscillation mark depth and, in particular, to minimize the formation of hook type defects that are prevalent on ultra low carbon grades. The major focus of the work was on developing a technique to allow h… more
Date: December 17, 2007
Creator: Cramb, Alan W.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Pump and probe damage testing for investigation of transient material modifications associated with laser damage in optical materials

Description: Laser-induced breakdown in the bulk of transparent dielectric materials is associated with the generation of extreme localized conditions of temperatures and pressures. In this work, we perform pump and probe damage testing experiments to investigate the evolution of transient absorption by the host material arising from modifications following confined laser energy deposition in fused silica and DKDP materials. Specifically, we measure the size of the damage sites observed in the region of spa… more
Date: October 18, 2007
Creator: Negres, R A; Feit, M D; DeMange, P; Bude, J D & Demos, S G
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Journal Article, full text

Description: Single-wall carbon nanotube #1;SWCNT#2; networks form a highly transparent and electrically conductive thin film that can be used to replace traditional transparent conducting oxides #1;TCOs#2; in a variety of applications. Here, the authors demonstrate their use as a transparent back contact in a near-infrared #1;NIR#2; transparent CdTe solar cell. SWCNT networks are hole-selective conductors and have a significantly greater NIR transparency than TCOs—qualities which could both make them very … more
Date: June 11, 2007
Creator: Barnes, T. M.; Wu, X.; Zhou, J.; Duda, A.; Lagemaat, J. van de; Weeks, C. L. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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

Description: 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… more
Date: October 31, 2007
Creator: Adams, J. J.; Jarboe, J.; Feit, M. & Hackel, R.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

LDA Calculations of Dislocation Mobility in Fe & Mo

Description: This Project was a collaborative effort between Murray Daw (Clemson) and Daryl Chrzan (LBNL/UCB). The main goal of this project was to accomplish the first-ever first principles calculations of the structure of the screw dislocation in Fe and to study the effects of stress and magnetization. The calculations were completed and reported at conferences. During the work on this project, the collaboration also tackled an important related question - the effect of periodic boundary conditions in dis… more
Date: July 13, 2007
Creator: Daw, Murray S. & Chrzan, Daryl
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

M5Si3(M=Ti, Nb, Mo) Based Transition-Metal Silicides for High Temperature Applications

Description: Transition metal silicides are being considered for future engine turbine components at temperatures up to 1600 C. Although significant improvement in high temperature strength, room temperature fracture toughness has been realized in the past decade, further improvement in oxidation resistance is needed. Oxidation mechanism of Ti{sub 5}Si{sub 3}-based alloys was investigated. Oxidation behavior of Ti{sub 5}Si{sub 3}-based alloy strongly depends on the atmosphere. Presence of Nitrogen alters th… more
Date: December 1, 2007
Creator: Tang, Zhihong
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries Government Documents Department
open access

Neutron generator production mission in a national laboratory.

Description: In the late 1980's the Department of Energy (DOE) faced a future budget shortfall. By the spring of 1991, the DOE had decided to manage this problem by closing three production plants and moving production capabilities to other existing DOE sites. As part of these closings, the mission assignment for fabrication of War Reserve (WR) neutron generators (NGs) was transferred from the Pinellas Plant (PP) in Florida to Sandia National Laboratories, New Mexico (SNL/NM). The DOE directive called for t… more
Date: August 1, 2007
Creator: Pope, Larry E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Improving Hardness and Toughness of Boride Composites Based on AIMgB14

Description: The search for new super-hard materials has usually focused on strongly bonded, highly symmetric crystal structures similar to diamond. The two hardest single-phase materials, diamond and cubic boron nitride (cBN), are metastable, and both must be produced at high temperatures and pressures, which makes their production costly. In 2000, a superhard composite based on a low-symmetry, boron-rich compound was reported. Since then, many advances have been made in the study of this AlMgB{sub 14}-TiB… more
Date: December 1, 2007
Creator: Peters, Justin Steven
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries Government Documents Department
open access

Micro and nano composites composed of a polymer matrix and a metal disperse phase.

Description: Low density polyethylene (LDPE) and Hytrel (a thermoplastic elastomer) were used as polymeric matrices in polymer + metal composites. The concentration of micrometric (Al, Ag and Ni) as well as nanometric particles (Al and Ag) was varied from 0 to 10 %. Composites were prepared by blending followed by injection molding. The resulting samples were analyzed by scanning electron microscopy (SEM) and focused ion beam (FIB) in order to determine their microstructure. Certain mechanical properties of… more
Date: December 2007
Creator: Olea Mejia, Oscar Fernando
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
open access

High Temperature Materials Laboratory User Program: 19th Annual Report, October 1, 2005 - September 30, 2006

Description: Annual Report contains overview of the High Temperature Materials Laboratory User Program and includes selected highlights of user activities for FY2006. Report is submitted to individuals within sponsoring DOE agency and to other interested individuals.
Date: August 1, 2007
Creator: Pasto, Arvid
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

SYNTHESIS OF METAL HYDRIDES BY MECHANICAL ALLOYING IN AN ATTRITOR MILL: FY07 STATUS REPORT

Description: The objective of this task was to demonstrate that metal hydrides could be produced by mechanical alloying in the quantities needed to support the tritium production facilities at the Savannah River Site. The objective for the FY07 portion of this task was to demonstrate the production of Zr-Fe getter materials by mechanical alloying and begin to optimize the milling parameters. Three starting compositions (ratios of elemental Zr and Fe powders) were selected and attritor milled under argon for… more
Date: November 8, 2007
Creator: Fox, K
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Catalog of the University of North Texas, 2007-2008, Undergraduate

Description: The UNT Undergraduate Bulletin includes information about class offerings as well as general information about the university (academic calendar, admissions and degree requirements, financial information, etc.) about research, and about the colleges and schools on campus. Index starts on page 544.
Date: July 2007
Creator: University of North Texas
Item Type: Refine your search to only Book
Partner: UNT Libraries
open access

Future Science Needs and Opportunities for Electron Scattering: Next-Generation Instrumentation and Beyond. Report of the Basic Energy Sciences Workshop on Electron Scattering for Materials Characterization, March 1-2, 2007

Description: To identify emerging basic science and engineering research needs and opportunities that will require major advances in electron-scattering theory, technology, and instrumentation.
Date: March 2, 2007
Creator: Miller, D. J.; Williams, D. B.; Anderson, I. M.; Schmid, A. K. & Zaluzec, N. J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Thermosetting Polymer-Matrix Composites for Strucutral Repair Applications

Description: Several classes of thermosetting polymer matrix composites were evaluated for use in structural repair applications. Initial work involved the characterization and evaluation of woven carbon fiber/epoxy matrix composites for structural pipeline repair. Cyanate ester resins were evaluated as a replacement for epoxy in composites for high-temperature pipe repair applications, and as the basis for adhesives for resin infusion repair of high-temperature composite materials. Carbon fiber/cyanate est… more
Date: December 1, 2007
Creator: Goertzen, William Kirby
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries Government Documents Department
open access

Structural and Magnetothermal Properties of Compounds: Yb5SixGe4-x,Sm5SixGe4-x, EuO, and Eu3O4

Description: The family of R{sub 5}Si{sub x}Ge{sub 4-x} alloys demonstrates a variety of unique physical phenomena related to magneto-structural transitions associated with reversible breaking and reforming of specific bonds that can be controlled by numerous external parameters such as chemical composition, magnetic field, temperature, and pressure. Therefore, R{sub 5}Si{sub x}Ge{sub 4-x} systems have been extensively studied to uncover the mechanism of the extraordinary magneto-responsive properties inclu… more
Date: May 9, 2007
Creator: Ahn, Kyunghan
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries Government Documents Department
open access

Microstructural Evolution and Interfacial Motion in Systems with Diffusion Barriers

Description: The initial goal of this research program was to model and to simulate phase transformations in systems containing diffusion barriers. The modeling work included the development and testing of code to describe mass flow, the kinetics of phase formation, elastic deformation, and subsequent microstructural evolution occurring during interdiffusion. The primary simulation tools to be used were a class of diffuse interface methods described by the Cahn-Hilliard and phase field equations for the tem… more
Date: June 30, 2007
Creator: Johnson, William C.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Catalog of the University of North Texas, 2007-2008, Graduate

Description: The UNT Graduate Bulletin includes information about class offerings as well as general information about the university (academic calendar, admissions and degree requirements, financial information, etc.) about research, and about the colleges and schools on campus. Index starts on page 455.
Date: July 2007
Creator: University of North Texas
Item Type: Refine your search to only Book
Partner: UNT Libraries
open access

Processing and Protection of Rare Earth Permanent Magnet Particulate for Bonded Magnet Applications

Description: Rapid solidification of novel mixed rare earth-iron-boron, MRE{sub 2}Fe{sub 14}B (MRE = Nd, Y, Dy; currently), magnet alloys via high pressure gas atomization (HPGA) have produced similar properties and structures as closely related alloys produced by melt spinning (MS) at low wheel speeds. Recent additions of titanium carbide and zirconium to the permanent magnet (PM) alloy design in HPGA powder (using He atomization gas) have made it possible to achieve highly refined microstructures with mag… more
Date: December 1, 2007
Creator: Sokolowski, Peter Kelly
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries Government Documents Department
open access

Indentation Size Effects in Single Crystal Copper as Revealed by Synchrotron X-ray Microdiffraction

Description: The indentation size effect (ISE) has been observed in numerous nanoindentation studies on crystalline materials; it is found that the hardness increases dramatically with decreasing indentation size - a 'smaller is stronger' phenomenon. Some have attributed the ISE to the existence of strain gradients and the geometrically necessary dislocations (GNDs). Since the GND density is directly related to the local lattice curvature, the Scanning X-ray Microdiffraction ({mu}SXRD) technique, which can … more
Date: November 19, 2007
Creator: Feng, G.; Budiman, A. S.; Nix, W. D.; Tamura, N. & Patel, J. R.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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