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Book Review Geostatistical Analysis of Compositional Data

Description: Compositional data are represented as vector variables with individual vector components ranging between zero and a positive maximum value representing a constant sum constraint, usually unity (or 100 percent). The earth sciences are flooded with spatial distributions of compositional data, such as concentrations of major ion constituents in natural waters (e.g. mole, mass, or volume fractions), mineral percentages, ore grades, or proportions of mutually exclusive categories (e.g. a water-oil-r… more
Date: March 26, 2007
Creator: Carle, S F
Partner: UNT Libraries Government Documents Department
open access

Characterization of an AO-OCT system

Description: Adaptive optics (AO) and optical coherence tomography (OCT) are powerful imaging modalities that, when combined, can provide high-volumetric-resolution, images of the retina. The AO-OCT system at UC Davis has been under development for 2 years and has demonstrated the utility of this technology for microscopic, volumetric, in vivo retinal imaging [1]. The current system uses an AOptix bimorph deformable mirror (DM) for low-order, high-stroke correction [2] and a 140-actuator Boston Micromachine… more
Date: July 26, 2007
Creator: Evans, J. W.; Zawadzki, R. J.; Jones, S.; Olivier, S. & Werner, J. S.
Partner: UNT Libraries Government Documents Department
open access

ELECTRICAL SAFETY IMPROVEMENT PROJECT A COMPLEX WIDE TEAMING INITIATIVE

Description: This paper describes the results of a year-long project, sponsored by the Energy Facility Contractors Group (EFCOG) and designed to improve overall electrical safety performance throughout Department of Energy (DOE)-owned sites and laboratories. As evidenced by focused metrics, the Project was successful primarily due to the joint commitment of contractor and DOE electrical safety experts, as well as significant support from DOE and contractor senior management. The effort was managed by an ass… more
Date: November 26, 2007
Creator: BJ, GRAY
Partner: UNT Libraries Government Documents Department
open access

Multiplexed Molecular Assays for Rapid Rule-Out of Foot-and-Mouth Disease

Description: A nucleic acid-based multiplexed assay was developed that combines detection of foot-and-mouth disease virus (FMDV) with rule-out assays for two other foreign animal diseases and four domestic animal diseases that cause vesicular or ulcerative lesions indistinguishable from FMDV infection in cattle, sheep and swine. The FMDV 'look-alike' diagnostic assay panel contains five PCR and twelve reverse transcriptase PCR (RT-PCR) signatures for a total of seventeen simultaneous PCR amplifications for … more
Date: June 26, 2007
Creator: Lenhoff, R; Naraghi-Arani, P; Thissen, J; Olivas, J; Carillo, C; Chinn, C et al.
Partner: UNT Libraries Government Documents Department
open access

Colliding with a crunching bubble

Description: In the context of eternal inflation we discuss the fate of Lambda = 0 bubbles when they collide with Lambda< 0 crunching bubbles. When the Lambda = 0 bubble is supersymmetric, it is not completely destroyed by collisions. If the domain wall separating the bubbles has higher tension than the BPS bound, it is expelled from the Lambda = 0 bubble and does not alter its long time behavior. If the domain wall saturates the BPS bound, then it stays inside the Lambda = 0 bubble and removes a finite … more
Date: March 26, 2007
Creator: Freivogel, Ben; Freivogel, Ben; Horowitz, Gary T. & Shenker, Stephen
Partner: UNT Libraries Government Documents Department
open access

Green (2(omega)) Laser Beam propagation in high-temperature Hohlraum Plasmas

Description: We demonstrate propagation and small backscatter losses of a frequency-doubled (2{omega}) laser beam interacting with inertial confinement fusion hohlraum plasmas. The electron temperature of 3.3 keV, approximately a factor of two higher than achieved in previous experiments with open geometry targets, approaches plasma conditions of high-fusion yield hohlraums. In this new temperature regime, we measure 2{omega} laser beam transmission approaching 80% with simultaneous backscattering losses of… more
Date: October 26, 2007
Creator: Niemann, C; Berger, R; Divol, L; Froula, D H; Jones, O S; Kirkwood, R K et al.
Partner: UNT Libraries Government Documents Department
open access

Thoughts on Verification of Nuclear Disarmament

Description: It is my pleasure to be here to day to participate in this Conference. My thanks to the organizers for preparing such an interesting agenda on a very difficult topic. My effort in preparing my presentation was performed under the auspices of the U.S. Department of Energy by University of California, Lawrence Livermore National Laboratory under Contract W-7405-Eng-48. And as many of you know Lawrence Livermore National Laboratory is now, as of Oct 1st, under contract to the Lawrence Livermore Na… more
Date: September 26, 2007
Creator: Dunlop, W H
Partner: UNT Libraries Government Documents Department
open access

Detailed Comparison of Blast Effects in Air and Vacuum

Description: Although blast mitigation is most often achieved with solid shielding, ambient gas pressure can also affect the coupling of shock waves to solid targets. In this work the role of air as an energy transfer medium was examined experimentally by subjecting identical large-area rectangular witness plates to short-range blast effects in air and vacuum ({approx}50 mtorr) at 25 C. The expanding reactant front of 3 kg C4 charges was observed by fast camera to be cylindrically symmetric in both air and … more
Date: July 26, 2007
Creator: Tringe, J W; Molitoris, J D; Garza, R G; Andreski, H G; Batteux, J D; Lauderbach, L M et al.
Partner: UNT Libraries Government Documents Department
open access

Examination of Scattering Volume Aligment in Thomson Scattering Off of a Shock Front in Argon

Description: Thomson scattering in argon gas successfully probed the region of plasma just behind the shock front. The instantaneous shock velocity can be inferred from the duration of the signal, taking into account the size and shape of the scattering volume. Possible misalignment of the probe beam and spectrometer slits greatly affects the size and shape of the scattering volume, and therefore affects the calculation of the instantaneous shock velocity.
Date: July 26, 2007
Creator: Reighard, A. B.; Froula, D. H.; Drake, R. P.; Ross, J. S. & Divol, L.
Partner: UNT Libraries Government Documents Department
open access

Abrupt onset of a second energy gap at the superconducting transition of underdoped Bi2212

Description: he superconducting gap--an energy scale tied to the superconducting phenomena--opens on the Fermi surface at the superconducting transition temperature (Tc) in conventional BCS superconductors. In underdoped high-Tc superconducting copper oxides, a pseudogap (whose relation to the superconducting gap remains a mystery) develops well above Tc (refs 1, 2). Whether the pseudogap is a distinct phenomenon or the incoherent continuation of the superconducting gap above Tc is one of the central questi… more
Date: May 26, 2007
Creator: Hussain, Zahid; Lee, W. S.; Vishik, I. M.; Tanaka, K.; Lu, D. H.; Sasagawa, T. et al.
Partner: UNT Libraries Government Documents Department
open access

REMOTE IN-CELL SAMPLING IMPROVEMENTS PROGRAM AT THESAVANNAH RIVER SITE (SRS) DEFENSE WASTE PROCESSING FACILITY (DWPF)

Description: Remote Systems Engineering (RSE) of the Savannah River National Lab (SRNL) in combination with the Defense Waste Processing Facility(DWPF) Engineering and Operations has evaluated the existing equipment and processes used in the facility sample cells for 'pulling' samples from the radioactive waste stream and performing equipment in-cell repairs/replacements. RSE has designed and tested equipment for improving remote in-cell sampling evolutions and reducing the time required for in-cell mainten… more
Date: November 26, 2007
Creator: Marzolf, A
Partner: UNT Libraries Government Documents Department
open access

Remarkable Strontium B-Site Occupancy in FerroelectricPb(Zr1-xTix)O3 Solid Solutions Doped with Cryolite-Type StrontiumNiobate

Description: New high-performance ferroelectric materials based on Pb(Zr{sub 1-x}Ti{sub x})O{sub 3} (PZT) that are doped with cryolite-type strontium niobate (SNO, Sr{sub 4}(Sr{sub 2-2y/3}Nb{sub 2+2y/3})O{sub 11+y}V{sub 0,1-y} with 0 {le} y {le} 1), hence denoted PZT:SNO, and their microscopic structure are described. The combination of exceptional piezoelectric properties, i.e. a piezoelectric strain constant of d{sub 33} {approx} 760 pm/V, with excellent stability and degradation resistance makes ferroele… more
Date: April 26, 2007
Creator: Feltz, A.; Schmidt-Winkel, P.; Schossman, M.; Booth, C.H. & Albering, J.
Partner: UNT Libraries Government Documents Department
open access

Climate response to projected changes in short-lived species under an A1B scenario from 2000-2050 in the GISS climate model

Description: We investigate the climate forcing from and response to projected changes in short-lived species and methane under the A1B scenario from 2000-2050 in the GISS climate model. We present a meta-analysis of new simulations of the full evolution of gas and aerosol species and other existing experiments with variations of the same model. The comparison highlights the importance of several physical processes in determining radiative forcing, especially the effect of climate change on stratosphere-tro… more
Date: March 26, 2007
Creator: Menon, Surabi; Shindell, Drew T.; Faluvegi, Greg; Bauer, Susanne E.; Koch, Dorothy M.; Unger, Nadine et al.
Partner: UNT Libraries Government Documents Department
open access

Compulsory Deep Mixing of 3He and CNO Isotopes on the First Giant Branch

Description: We have found a deep-mixing process which occurs during First Giant Branch (FGB) evolution. It begins at the point in evolution where the surface convection zone (SCZ), having previously grown in size, starts to shrink, and it is driven by a local minimum that develops in the mean molecular weight as a result of the burning of {sup 3}He. This mixing can solve two important observational problems. One is why the interstellar medium (ISM) has not been considerably enriched in {sup 3}He since the … more
Date: July 26, 2007
Creator: Eggleton, P P; Dearborn, D P & Lattanzio, J
Partner: UNT Libraries Government Documents Department
open access

Synthesis of Non-molecular Nitrogen Phases at Mbar Pressures by Direct Laser-heating

Description: Direct laser heating of molecular N2 to above 1400 K at 120-130 GPa results in the formation of a reddish amorphous phase and a transparent crystalline solid above 2000 K. Raman and x-ray data confirm that the transparent phase is cubic-gauche nitrogen (cg-N), while the reddish color of the amorphous phase might indicate the presence of N=N dish bonds. The quenched amorphous phase is stable down to at least 70GPa, analogous to cg-N, and could be a new non-molecular phase or an extension of the … more
Date: March 26, 2007
Creator: Lipp, M. J.; Klepeis, J. P.; Baer, B. J.; Cynn, H.; Evans, W. J.; Iota, V. et al.
Partner: UNT Libraries Government Documents Department
open access

TANK 5 SAMPLING

Description: Tank 5 at the Savannah River Site has been used to store high level waste and is currently undergoing waste removal processes in preparation for tank closure. Samples were taken from two locations to determine the contents in support of Documented Safety Analysis (DSA) development for chemical cleaning. These samples were obtained through the use of the Drop Core Sampler and the Snowbank Sampler developed by the Engineered Equipment & Systems (EES) group of the Savannah River National Laborator… more
Date: November 26, 2007
Creator: Vrettos, N; William Cheng, W & Thomas Nance, T
Partner: UNT Libraries Government Documents Department
open access

Fast Prediction of HCCI and PCCI Combustion with an Artificial Neural Network-Based Chemical Kinetic Model

Description: We have added the capability to look at in-cylinder fuel distributions using a previously developed ignition model within a fluid mechanics code (KIVA3V) that uses an artificial neural network (ANN) to predict ignition (The combined code: KIVA3V-ANN). KIVA3V-ANN was originally developed and validated for analysis of Homogeneous Charge Compression Ignition (HCCI) combustion, but it is also applicable to the more difficult problem of Premixed Charge Compression Ignition (PCCI) combustion. PCCI co… more
Date: September 26, 2007
Creator: Piggott, W. T.; Aceves, S. M.; Flowers, D. L. & Chen, J. Y.
Partner: UNT Libraries Government Documents Department
open access

A Linear Scaling Three Dimensional Fragment Method for Large ScaleElectronic Structure Calculations

Description: We present a novel linear scaling ab initio total energyelectronic structure calculation method, which is simple to implement,easily to parallelize, and produces essentially thesame results as thedirect ab initio method, while it could be thousands of times faster.Using this method, we have studied the dipole moments of CdSe quantumdots, and found both significant bulk and surface contributions. The bulkdipole contribution cannot simply be estimated from the bulk spontaneouspolarization value b… more
Date: July 26, 2007
Creator: Wang, Lin-Wang; Zhao, Zhengji & Meza, Juan
Partner: UNT Libraries Government Documents Department
open access

Catalytic Deprotection of Acetals In Strongly Basic Solution Usinga Self-Assembled Supramolecular 'Nanozyme'

Description: Acetals are among the most commonly used protecting groups for aldehydes and ketones in organic synthesis due to their ease of installation and resistance to cleavage in neutral or basic solution.[1] The common methods for hydrolyzing acetals almost always involve the use of either Broensted acid or Lewis acid catalysts.[2] Usually aqueous acids or organic solutions acidified with organic or inorganic acids have been used for reconversion of the acetal functionality to the corresponding carbony… more
Date: July 26, 2007
Creator: Pluth, Michael D.; Bergman, Robert G. & Raymond, Kenneth N.
Partner: UNT Libraries Government Documents Department
open access

Diagnostic evaluation of a multiplexed RT-PCR microsphere array assay for the detection of foot-and-mouth disease virus and look-alike disease viruses

Description: A high-throughput multiplexed assay was developed for the differential laboratory diagnosis of foot-and-mouth disease virus (FMDV) from viruses which cause clinically similar diseases of livestock. This assay simultaneously screens for five RNA and two DNA viruses using multiplexed reverse transcription PCR (mRT-PCR) amplification coupled with a microsphere hybridization array and flow-cytometric detection. Two of the seventeen primer-probe sets included in this multiplex assay were adopted fro… more
Date: July 26, 2007
Creator: Hindson, B J; Reid, S M; Baker, B R; Ebert, K; Ferris, N P; Bentley Tammero, L F et al.
Partner: UNT Libraries Government Documents Department
open access

Status of the Nif Power Conditioning System

Description: The NIF Power Conditioning System provides the pulsed excitation required to drive flashlamps in the laser's optical amplifiers. Modular in design, each of the 192 Main Energy Storage Modules (MESMs) storage up to 2.2 MJ of electrical energy in its capacitor bank before delivering the energy to 20 pairs of flashlamps in a 400 {micro}s pulse (10% power points). The peak current of each MESM discharge is 0.5 MA. Production, installation, commissioning and operation of the NIF Power Conditioning c… more
Date: July 26, 2007
Creator: Arnold, P.; Hulsey, S.; Ullery, G.; Petersen, D.; Pendleton, D.; Ollis, C. et al.
Partner: UNT Libraries Government Documents Department
open access

Low doses of alpha particles do not induce sister chromatid exchanges in bystander Chinese hamster cells defective in homologous recombination

Description: We reported previously that the homologous recombinational repair (HRR)-deficient Chinese hamster mutant cell line irs3 (deficient in the Rad51 paralog Rad51C) showed only a 50% spontaneous frequency of sister chromatid exchange (SCE) as compared to parental wild-type V79 cells. Furthermore, when irradiated with very low doses of alpha particles, SCEs were not induced in irs3 cells, as compared to a prominent bystander effect observed in V79 cells (Nagasawa et al., Radiat. Res. 164, 141-147, 20… more
Date: October 26, 2007
Creator: Nagasawa, H; Wilson, P F; Chen, D J; Thompson, L H; Bedford, J S & Little, J B
Partner: UNT Libraries Government Documents Department
open access

Diamond Amplified Photocathodes

Description: High-average-current linear electron accelerators require photoinjectors capable of delivering tens to hundreds of mA average current, with peak currents of hundreds of amps. Standard photocathodes face significant challenges in meeting these requirements, and often have short operational lifetimes in an accelerator environment. We report on recent progress toward development of secondary emission amplifiers for photocathodes, which are intended to increase the achievable average current while … more
Date: November 26, 2007
Creator: Smedley, J.; Ben-Zvi, Ilan; Bohon, J.; Chang, X.; Grover, R.; Isakovic, A. et al.
Partner: UNT Libraries Government Documents Department
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