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Workshop on Excellence Empowered by a Diverse Academic Workforce: Achieving Racial & Ethnic Equity in Chemistry

Description: The purpose of the Workshop 'Excellence Empowered by a Diverse Academic Workforce: Achieving Racial & Ethnic Equity in Chemistry' was to promote the development of a cadre of academic leaders who create, implement and promote programs and strategies for increasing the number of racial and ethnic minorities to equitable proportions on the faculties of departments throughout the academic chemistry community. An important objective of the workshop was to assist in creating an informed and committe… more
Date: February 13, 2008
Creator: Ali, Hassan. B.
Partner: UNT Libraries Government Documents Department
open access

Measurements of the asymmetric, dynamic sheath around a pulse biased sphere immersed in flowing metal plasma

Description: A long-probe technique was utilized to record the expansion and retreat of the dynamic sheath around a spherical substrate immersed in pulsed cathode arc metal plasma. Positively biased, long cylindrical probes were placed on the side and downstream of a negatively pulsed biased stainless steel sphere of 1" (25.4 mm) diameter. The amplitude and width of the negative high voltage pulses (HVP) were 2 kV, 5 kV, 10 kV, and 2 mu s, 4 mu s, 10 mu s, respectively. The variation of the probe (elec… more
Date: June 13, 2008
Creator: Anders, Andre; Wu, Hongchen & Anders, Andre
Partner: UNT Libraries Government Documents Department
open access

Electronic Structure of Halogen Doped CuCr2Se4

Description: We have employed element and chemically sensitive X-ray absorption spectroscopy (XAS) and X-ray magnetic circular dichroism (XMCD) in order to address a long standing controversy regarding the electronic and magnetic state of CuCr{sub 2}Se{sub 4} via halogen doping of the Se anion site in CuCr{sub 2}Se{sub 4-x}Y{sub x} (Y=Cl and Br). Long range magnetic order is observed above room temperature for all samples. The Cr L{sub 2,3} XAS spectra show a prevalent 3+ valence for the Cr ions independent… more
Date: September 13, 2008
Creator: Arenholz, Elke; Liberati, M.; Neulinger, J. R.; Chopdekar, R. V.; Bettinger, J. S.; Arenholz, E. et al.
Partner: UNT Libraries Government Documents Department
open access

Observation of B0 -> chi_c0 K*0 and Evidence of B+ -> chi_c0 K*+

Description: The authors present the observation of the decay B{sup 0} {yields} {chi}{sub c0}K*{sup 0} as well as evidence of B{sup +} {yields} {chi}{sub c0}K*{sup +}, with an 8.9 and a 3.6 standard deviation significance, respectively, using a data sample of 454 million {Upsilon}(4S) {yields} B{bar B} decays collected with the BABAR detector at the PEP-II B meson factory located at the Standard Linear Accelerator Center (SLAC). The measured branching fractions are: {Beta}(B{sup 0} {yields} {chi}{sub c0}K*{… more
Date: August 13, 2008
Creator: Aubert, B.
Partner: UNT Libraries Government Documents Department
open access

Microaspiration for high-pressure freezing: a new method for ultrastructural preservation of fragile and sparse tissues for TEM and electron tomography

Description: High-pressure freezing is the preferred method to prepare thick biological specimens for ultrastructural studies. However, the advantages obtained by this method often prove unattainable for samples that are difficult to handle during the freezing and substitution protocols. Delicate and sparse samples are difficult to manipulate and maintain intact throughout the sequence of freezing, infiltration, embedding, and final orientation for sectioning and subsequent TEM imaging. An established appro… more
Date: February 13, 2008
Creator: Auer, Manfred; Triffo, W. J.; Palsdottir, H.; McDonald, K. L.; Inman, J. L.; Bissell, M. J. et al.
Partner: UNT Libraries Government Documents Department
open access

Product Quality Assurance for Off-Grid Lighting in Africa

Description: Although the emergence of markets for high efficiency off-grid lighting technologies holds promise, realizing the potential of this opportunity on a long-term, sustainable basis requires careful attention to issues of product quality, consumer protection, and the potential for significant 'market spoiling', in anticipation of increases of sales of low cost, low performance off-grid lighting products. The goal of the Lighting Africa quality assurance workshop was to articulate strategies to miti… more
Date: July 13, 2008
Creator: Bank, World; Mills, Evan & Mills, Evan
Partner: UNT Libraries Government Documents Department
open access

Generation IV PR and PP Methods and Applications

Description: This paper presents an evaluation methodology for proliferation resistance and physical protection (PR&PP) of Generation IV nuclear energy systems (NESs). For a proposed NES design, the methodology defines a set of challenges, analyzes system response to these challenges, and assesses outcomes. The challenges to the NES are the threats posed by potential actors (proliferant States or sub-national adversaries). The characteristics of Generation IV systems, both technical and institutional, a… more
Date: October 13, 2008
Creator: Bari, R. A.
Partner: UNT Libraries Government Documents Department
open access

MARKOV Model Application to Proliferation Risk Reduction of an Advanced Nuclear System

Description: The Generation IV International Forum (GIF) emphasizes proliferation resistance and physical protection (PR&PP) as a main goal for future nuclear energy systems. The GIF PR&PP Working Group has developed a methodology for the evaluation of these systems. As an application of the methodology, Markov model has been developed for the evaluation of proliferation resistance and is demonstrated for a hypothetical Example Sodium Fast Reactor (ESFR) system. This paper presents the case of diver… more
Date: July 13, 2008
Creator: Bari, R. A.
Partner: UNT Libraries Government Documents Department
open access

Design and Formation of a Large, Tetrahedral, Metal-ligand Cluster Using 1,1'-Binaphthyl Ligands

Description: Many chemists have been fascinated with the development of discrete supramolecular structures that encapsulate guest molecules. These structures can be assembled through covalent or hydrogen bonds, electrostatic or metal-ligand interactions. These host structures have provided valuable insight into the forces involved in small molecule recognition. Our work has focused on the design and study of metal-ligand clusters of varying sizes. The naphthalene [M{sub 4}L{sub 6}]{sup 12-} cluster 1, shown… more
Date: March 13, 2008
Creator: Biros, Shannon M.; Yeh, Robert M. & Raymond, Kenneth N.
Partner: UNT Libraries Government Documents Department
open access

Mechanisms of disease: epithelial-mesenchymal transition and back again: does cellular plasticity fuel neoplastic progression?

Description: Epithelial-mesenchymal transition (EMT) is a conversion that facilitates organ morphogenesis and tissue remodeling in physiological processes such as embryonic development and wound healing. A similar phenotypic conversion is also detected in fibrotic diseases and neoplasia, which is associated with disease progression. EMT in cancer epithelial cells often seems to be an incomplete and bi-directional process. In this Review, we discuss the phenomenon of EMT as it pertains to tumor development, … more
Date: February 13, 2008
Creator: Bissell, Mina J; Turley, Eva A.; Veiseh, Mandana; Radisky, Derek C. & Bissell, Mina J.
Partner: UNT Libraries Government Documents Department
open access

DHS Regional Reachback: Rapid Expert Radiation Alarm Assistance.

Description: Following assessments that attacks with radiological and nuclear weapons are possible, detection system deployments are being supported at national and local levels. Detection systems include both, highly sensitive but non-discriminating detectors, as well as detectors and algorithms capable of distinguishing and identifying gamma rays by energy. The latter systems, usually handheld systems based on sodium iodide detectors, also provide analysis of the specific radionuclides present and are ref… more
Date: July 13, 2008
Creator: Bowerman, B.; Archer, D.; Young, J.; Monetti, M. & Savage, B.
Partner: UNT Libraries Government Documents Department
open access

THE HYDROLYSIS AND OXIDATION BEHAVIOR OF LITHIUM BOROHYDRIDE AND MAGNESIUM HYDRIDE DETERMINED BY CALORIMETRY

Description: Lithium borohydride, magnesium hydride and the 2:1 'destabilized' ball milled mixtures (2LiBH{sub 4}:MgH{sub 2}) underwent liquid phase hydrolysis, gas phase hydrolysis and air oxidation reactions monitored by isothermal calorimetry. The experimentally determined heats of reaction and resulting products were compared with those theoretically predicted using thermodynamic databases. Results showed a discrepancy between the predicted and observed hydrolysis and oxidation products due to both kine… more
Date: March 13, 2008
Creator: Brinkman, K; Donald Anton, D; Joshua Gray, J & Bruce Hardy, B
Partner: UNT Libraries Government Documents Department
open access

The AdS/CFT Correspondence and Light-Front QCD

Description: We identify an invariant light-front coordinate {zeta} which allows the separation of the dynamics of quark and gluon binding from the kinematics of constituent spin and internal orbital angular momentum. The result is a single-variable light-front Schroedinger equation for QCD which determines the eigenspectrum and the light-front wavefunctions of hadrons for general spin and orbital angular momentum. This frame-independent light-front wave equation is equivalent to the equations of motion whi… more
Date: October 13, 2008
Creator: Brodsky, Stanley J. & de Teramond, Guy F.
Partner: UNT Libraries Government Documents Department
open access

Radiation monitoring with CVD Diamonds and PIN Diodes at BaBar

Description: The BaBar experiment at the Stanford Linear Accelerator Center has been using two polycrystalline chemical vapor deposition (pCVD) diamonds and 12 silicon PIN diodes for radiation monitoring and protection of the Silicon Vertex Tracker (SVT). We have used the pCVD diamonds for more than 3 years, and the PIN diodes for 7 years. We will describe the SVT and SVT radiation monitoring system as well as the operational difficulties and radiation damage effects on the PIN diodes and pCVD diamonds in a… more
Date: February 13, 2008
Creator: Bruinsma, M.; Burchat, P.; Curry, S.; Edwards, A.J.; Kagan, H.; Kass, R. et al.
Partner: UNT Libraries Government Documents Department
open access

Hyperfine Quenching of the 2s2p 3P0 State of Berylliumlike Ions

Description: The hyperfine-induced 2s2p {sup 3}P{sub 0}-2s{sup 2} {sup 1}S{sub 0} transition rate for Be-like {sup 47}Ti{sup 18+} was recently measured in a storage-ring experiment by Schippers et al. [Phys. Rev. Lett. 98, 033001 (2007)]. The measured value of 0.56(3) s{sup -1} is almost 60% larger than the theoretical value of 0.356 s{sup -1} from a multiconfiguration Dirac-Fock calculation by Marques et al. [Phys. Rev. A 47, 929 (1993)]. In this work, we use a large-scale relativistic configuration-intera… more
Date: March 13, 2008
Creator: Cheng, K T; Chen, M H & Johnson, W R
Partner: UNT Libraries Government Documents Department
open access

Multi-year search for a diffuse flxu of muon neutrinos with AMANDA-II

Description: A search for TeV-PeV muon neutrinos from unresolved sources was performed on AMANDA-II data collected between 2000 and 2003 with an equivalent livetime of 807 days. This diffuse analysis sought to find an extraterrestrial neutrino flux from sources with non-thermal components. The signal is expected to have a harder spectrum than the atmospheric muon and neutrino backgrounds. Since no excess of events was seen in the data over the expected background, an upper limit of E{sup 2}{Phi}{sub 90%C.L.… more
Date: April 13, 2008
Creator: Collaboration, IceCube; Klein, Spencer; Achterberg, A. & Collaboration, IceCube
Partner: UNT Libraries Government Documents Department
open access

Action-Oriented Benchmarking: Concepts and Tools

Description: Most energy benchmarking tools provide static feedback on how one building compares to a larger set of loosely similar buildings, without providing information at the end-use level or on what can be done to reduce consumption, cost, or emissions. In this article--Part 1 of a two-part series--we describe an 'action-oriented benchmarking' approach, which extends whole-building energy benchmarking to include analysis of system and component energy use metrics and features. Action-oriented benchmar… more
Date: February 13, 2008
Creator: Commission, California Energy; Mathew, Paul; Mills, Evan; Mathew, Paul; Piette, Mary Ann; Bourassa, Norman et al.
Partner: UNT Libraries Government Documents Department
open access

The US Support Program to IAEA Safeguards Priority of Containment and Surveillance

Description: The United States Support Program (USSP) priority for containment and surveillance (US) focuses on maintaining or improving the reliability and cost-effectiveness of C/S systems for IAEA safeguards, expanding the number of systems that are unattended and remotely monitored, and developing verification methods that help streamline the on-site inspection process. Existing IAEA C/S systems have evolved to become complex, integrated systems, which may include active seals, nondestructive assay (NDA… more
Date: June 13, 2008
Creator: Diaz,R.A.
Partner: UNT Libraries Government Documents Department
open access

Prompt gamma activation analysis (PGAA) and short-lived neutron activation analysis (NAA) applied to the characterization of legacy materials

Description: Without quality historical records that provide the composition of legacy materials, the elemental and/or chemical characterization of such materials requires a manual analytical strategy that may expose the analyst to unknown toxicological hazards. In addition, much of the existing legacy inventory also incorporates radioactivity, and, although radiological composition may be determined by various nuclear-analytical methods, most importantly, gamma-spectroscopy, current methods of chemical cha… more
Date: February 13, 2008
Creator: Firestone, Richard B; English, G. A.; Firestone, R. B.; Perry, D. L.; Reijonen, J. P.; Leung, Ka-Ngo et al.
Partner: UNT Libraries Government Documents Department
open access

Constraining Cosmic Evolution of Type Ia Supernovae

Description: We present the first large-scale effort of creating composite spectra of high-redshift type Ia supernovae (SNe Ia) and comparing them to low-redshift counterparts. Through the ESSENCE project, we have obtained 107 spectra of 88 high-redshift SNe Ia with excellent light-curve information. In addition, we have obtained 397 spectra of low-redshift SNe through a multiple-decade effort at Lick and Keck Observatories, and we have used 45 ultraviolet spectra obtained by HST/IUE. The low-redshift spect… more
Date: February 13, 2008
Creator: Foley, Ryan J.; Filippenko, Alexei V.; Aguilera, C.; Becker, A. C.; Blondin, S.; Challis, P. et al.
Partner: UNT Libraries Government Documents Department
open access

Nanofiltration of Electrolyte Solutions by Sub-2nm Carbon Nanotube Membranes

Description: Both MD simulations and experimental studies have shown that liquid and gas flow through carbon nanotubes with nanometer size diameter is exceptionally fast. For applications in separation technology, selectivity is required together with fast flow. In this work, we use pressure-driven filtration experiments to study ion exclusion in silicon nitride/sub-2-nm CNT composite membranes as a function of solution ionic strength, pH, and ion valence. We show that carbon nanotube membranes exhibit sign… more
Date: March 13, 2008
Creator: Fornasiero, F.; Park, H. G.; Holt, J. K.; Stadermann, M.; Kim, S.; In, J. B. et al.
Partner: UNT Libraries Government Documents Department
open access

Creep Testing Plastic-Bonded Explosives in Uni-axial Compression

Description: High fidelity measurements of time-dependent strain in the plastic-bonded explosives LX-17-1 and PBX 9502 have been performed under constant, uni-axial, compressive load using a custom designed apparatus. The apparatus uses a combination of extensometers and linear variable differential transformers coupled with a data acquisition system, thermal controls, and gravitational loading. The materials being tested consist of a crystalline explosive material mixed with a polymeric binder. The behavio… more
Date: March 13, 2008
Creator: Gagliardi, F J & Cunningham, B J
Partner: UNT Libraries Government Documents Department
open access

The Structural Quality of AlxGa1-xN Epitaxial Layers Grown by Digitally-AlloyedModulated Precursor Epitaxy Determined by Transmission Electron Microscopy

Description: Al(x)Ga(1-x)N layers of varying composition (0.5<x(Al)<1.0) grown in the digitally-alloyed modulated precursor epitaxial regime employing AlN and GaN binary sub-layers by metalorganic chemical vapor deposition on AlN templates were characterized by transmission electron microscopy techniques. Fine lamellae were observed in bright field images that indicate a possible variation in composition due to the modulated nature of growth. In higher Ga content samples (x(Al)<0.75), a composition… more
Date: October 13, 2008
Creator: Hawkridge, M. E.; Liliental-Weber, Zuzanna; Kim, Hee Jin; Choi, S.; Yoo, D.; Ryou, Jae-Hyun et al.
Partner: UNT Libraries Government Documents Department
open access

The U.S. Support Program to IAEA Safeguards - Destructive Analysis

Description: The U.S. Support Program (USSP) to IAEA Safeguards priority of destructive analysis is aimed at strengthening the IAEA's ability to use destructive analysis as a safeguards tool. IAEA inspectors bring back nuclear and environmental samples from inspections, which are first cataloged by the IAEA and then analyzed by a network of laboratories located in many Member States and the IAEA's own Safeguards Analytical Laboratory in Seibersdorf, Austria. Historically, the USSP was instrumental in introd… more
Date: July 13, 2008
Creator: Hoffheins,B.
Partner: UNT Libraries Government Documents Department
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