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2010 INORGANIC CHEMISTRY GORDON RESEARCH CONFERENCE JUNE 20 - 25, 2010 (open access)

2010 INORGANIC CHEMISTRY GORDON RESEARCH CONFERENCE JUNE 20 - 25, 2010

The Inorganic Chemistry GRC is one of the longest-standing of the GRCs, originating in 1951. Over the years, this conference has played a role in spawning many other GRCs in specialized fields, due to the involvement of elements from most of the periodic table. These include coordination, organometallic, main group, f-element, and solid state chemistries; materials science, catalysis, computational chemistry, nanotechnology, bioinorganic, environmental, and biomedical sciences just to name a few. The 2010 Inorganic Chemistry GRC will continue this tradition, where scientists at all levels from academic, industrial, and national laboratories meet to define the important problems in the field and to highlight emerging opportunities through exchange of ideas and discussion of unpublished results. Invited speakers will present on a wide variety of topics, giving attendees a look at areas both inside and outside of their specialized areas of interest. In addition to invited speakers, the poster sessions at GRCs are a key feature of the conference. All conferees at the Inorganic Chemistry GRC are invited to present a poster on their work, and here the informal setting promotes the free exchange of ideas and fosters new relationships. As in previous years, we will offer poster presenters the opportunity to …
Date: June 25, 2010
Creator: LOCKEMEYER, JOHN
System: The UNT Digital Library
Accelerator Production Options for 99MO (open access)

Accelerator Production Options for 99MO

Shortages of {sup 99}Mo, the most commonly used diagnostic medical isotope, have caused great concern and have prompted numerous suggestions for alternate production methods. A wide variety of accelerator-based approaches have been suggested. In this paper we survey and compare the various accelerator-based approaches.
Date: August 25, 2010
Creator: Bertsche, Kirk
System: The UNT Digital Library
Activation Energy of Tantalum-Tungsten Oxide Thermite Reaction (open access)

Activation Energy of Tantalum-Tungsten Oxide Thermite Reaction

The activation energy of a high melting temperature sol-gel (SG) derived tantalum-tungsten oxide thermite composite was determined using the Kissinger isoconversion method. The SG derived powder was consolidated using the High Pressure Spark Plasma Sintering (HPSPS) technique to 300 and 400 C to produce pellets with dimensions of 5 mm diameter by 1.5 mm height. A custom built ignition setup was developed to measure ignition temperatures at high heating rates (500-2000 C {center_dot} min{sup -1}). Such heating rates were required in order to ignite the thermite composite. Unlike the 400 C samples, results show that the samples consolidated to 300 C undergo an abrupt change in temperature response prior to ignition. This change in temperature response has been attributed to the crystallization of the amorphous WO{sub 3} in the SG derived Ta-WO{sub 3} thermite composite and not to a pre-ignition reaction between the constituents. Ignition temperatures for the Ta-WO{sub 3} thermite ranged from approximately 465-670 C. The activation energy of the SG derived Ta-WO{sup 3} thermite composite consolidated to 300 and 400 C were determined to be 37.787 {+-} 1.58 kJ {center_dot} mol{sup -1} and 57.381 {+-} 2.26 kJ {center_dot} mol{sup -1}, respectively.
Date: February 25, 2010
Creator: Cervantes, O.; Kuntz, J.; Gash, A. & Munir, Z.
System: The UNT Digital Library
The added economic and environmental value of plug-in electric vehicles connected to commercial building microgrids (open access)

The added economic and environmental value of plug-in electric vehicles connected to commercial building microgrids

Connection of electric storage technologies to smartgrids or microgrids will have substantial implications for building energy systems. In addition to potentially supplying ancillary services directly to the traditional centralized grid (or macrogrid), local storage will enable demand response. As an economically attractive option, mobile storage devices such as plug-in electric vehicles (EVs) are in direct competition with conventional stationary sources and storage at the building. In general, it is assumed that they can improve the financial as well as environmental attractiveness of renewable and fossil based on-site generation (e.g. PV, fuel cells, or microturbines operating with or without combined heat and power). Also, mobile storage can directly contribute to tariff driven demand response in commercial buildings. In order to examine the impact of mobile storage on building energy costs and carbon dioxide (CO2) emissions, a microgrid/distributed-energy-resources (DER) adoption problem is formulated as a mixed-integer linear program with minimization of annual building energy costs applying CO2 taxes/CO2 pricing schemes. The problem is solved for a representative office building in the San Francisco Bay Area in 2020. By using employees' EVs for energy management, the office building can arbitrage its costs. But since the car battery lifetime is reduced, a business model …
Date: August 25, 2010
Creator: Stadler, Michael; Momber, Ilan; Megel, Olivier; Gomez, Tomás; Marnay, Chris; Beer, Sebastian et al.
System: The UNT Digital Library
The AdS/QCD Correspondence and Exclusive Processes (open access)

The AdS/QCD Correspondence and Exclusive Processes

The AdS/CFT correspondence between theories in AdS space and conformal field theories in physical space-time provides an analytic, semi-classical, color-confining model for strongly-coupled QCD. The soft-wall AdS/QCD model modified by a positive-sign dilaton metric leads to a remarkable one-parameter description of nonperturbative hadron dynamics at zero quark mass, including a zero-mass pion and a Regge spectrum of linear trajectories with the same slope in orbital angular momentum L and radial quantum number n for both mesons and baryons. One also predicts the form of the non-perturbative effective coupling {alpha}{sub s}{sup AdS}(q) and its {beta}-function which agrees with the effective coupling {alpha}{sub ga} extracted from the Bjorken sum rule. Light-front holography, which connects the fifth-dimensional coordinate of AdS space z to an invariant impact separation variable {zeta}, allows one to compute the analytic form of the frame-independent light-front wavefunctions, the fundamental entities which encode hadron properties as well as decay constants, form factors, deeply virtual Compton scattering, exclusive heavy hadron decays and other exclusive scattering amplitudes. One thus obtains a relativistic description of hadrons in QCD at the amplitude level with dimensional counting for hard exclusive reactions at high momentum transfer. As specific examples we discuss the behavior of the pion …
Date: August 25, 2010
Creator: Brodsky, Stanley J.; /SLAC /Southern Denmark U., CP3-Origins; de Teramond, Guy F.; U., /Costa Rica; Deur, Alexandre & Lab, /Jefferson
System: The UNT Digital Library
All Tree-level Amplitudes in Massless QCD (open access)

All Tree-level Amplitudes in Massless QCD

We derive compact analytical formulae for all tree-level color-ordered gauge theory amplitudes involving any number of external gluons and up to three massless quark-anti-quark pairs. A general formula is presented based on the combinatorics of paths along a rooted tree and associated determinants. Explicit expressions are displayed for the next-to-maximally helicity violating (NMHV) and next-to-next-to-maximally helicity violating (NNMHV) gauge theory amplitudes. Our results are obtained by projecting the previously-found expressions for the super-amplitudes of the maximally supersymmetric Yang-Mills theory (N = 4 SYM) onto the relevant components yielding all gluon-gluino tree amplitudes in N = 4 SYM. We show how these results carry over to the corresponding QCD amplitudes, including massless quarks of different flavors as well as a single electroweak vector boson. The public Mathematica package GGT is described, which encodes the results of this work and yields analytical formulae for all N = 4 SYM gluon-gluino trees. These in turn yield all QCD trees with up to four external arbitrary-flavored massless quark-anti-quark-pairs.
Date: October 25, 2010
Creator: Dixon, Lance J.; Henn, Johannes M.; Plefka, Jan & Schuster, Theodor
System: The UNT Digital Library
Assessing out-of-band flare effects at the wafer level for EUV lithography (open access)

Assessing out-of-band flare effects at the wafer level for EUV lithography

To accurately estimate the flare contribution from the out-of-band (OOB), the integration of a DUV source into the SEMATECH Berkeley 0.3-NA Micro-field Exposure tool is proposed, enabling precisely controlled exposures along with the EUV patterning of resists in vacuum. First measurements evaluating the impact of bandwidth selected exposures with a table-top set-up and subsequent EUV patterning show significant impact on line-edge roughness and process performance. We outline a simulation-based method for computing the effective flare from resist sensitive wavelengths as a function of mask pattern types and sizes. This simulation method is benchmarked against measured OOB flare measurements and the results obtained are in agreement.
Date: January 25, 2010
Creator: George, Simi; Naulleau, Patrick; Kemp, Charles; Denham, Paul & Rekawa, Senajith
System: The UNT Digital Library
B-meson decays to eta' rho, eta' f0, and eta' K* (open access)

B-meson decays to eta' rho, eta' f0, and eta' K*

We present measurements of B-meson decays to the final states {eta}{prime} {rho}, {eta}{prime} f{sub 0}, and {eta}{prime} K*, where K* stands for a vector, scalar, or tensor strange meson. We observe a significant signal or evidence for {eta}{prime} {rho}{sup +} and all the {eta}{prime}K* channels. We also measure, where applicable, the charge asymmetries, finding results consistent with no direct CP violation in all cases. The measurements are performed on a data sample consisting of 467 x 10{sup 6} B{bar B} pairs, collected with the BABAR detector at the PEP-II e{sup +}e{sup -} collider at the SLAC National Accelerator Laboratory. Our results favor the theoretical predictions from perturbative QCD and QCD Factorization and we observe an enhancement of the tensor K*{sub 2} (1430) with respect to the vector K*(892) component.
Date: August 25, 2010
Creator: del Amo Sanchez, P.; Lees, J. P.; Poireau, V.; Prencipe, E.; Tisserand, V.; Garra Tico, J. et al.
System: The UNT Digital Library
Billion-atom Synchronous Parallel Kinetic Monte Carlo Simulations of Critical 3D Ising Systems (open access)

Billion-atom Synchronous Parallel Kinetic Monte Carlo Simulations of Critical 3D Ising Systems

None
Date: May 25, 2010
Creator: Martinez, E.; Monasterio, P. R. & Marian, J.
System: The UNT Digital Library
A Case for Including Transactions in OpenMP (open access)

A Case for Including Transactions in OpenMP

Transactional Memory (TM) has received significant attention recently as a mechanism to reduce the complexity of shared memory programming. We explore the potential of TM to improve OpenMP applications. We combine a software TM (STM) system to support transactions with an OpenMP implementation to start thread teams and provide task and loop-level parallelization. We apply this system to two application scenarios that reflect realistic TM use cases. Our results with this system demonstrate that even with the relatively high overheads of STM, transactions can outperform OpenMP critical sections by 10%. Overall, our study demonstrates that extending OpenMP to include transactions would ease programming effort while allowing improved performance.
Date: January 25, 2010
Creator: Wong, M.; Bihari, B. L.; de Supinski, B. R.; Wu, P.; Michael, M.; Liu, Y. et al.
System: The UNT Digital Library
Characterization of LER propagation in resists: Underlayer interfaces in ultra-thin resist films (open access)

Characterization of LER propagation in resists: Underlayer interfaces in ultra-thin resist films

None
Date: February 25, 2010
Creator: Georege, Simi; Naulleau, Patrick; Krishnamoorthy, Ahila; Wu, Zeyu; Kennedy, Joseph; Rutter, Edward et al.
System: The UNT Digital Library
COMPARISON OF SIMULATION CODES FOR MICROWAVE INSTABILITY IN BUNCHED BEAMS (open access)

COMPARISON OF SIMULATION CODES FOR MICROWAVE INSTABILITY IN BUNCHED BEAMS

In accelerator design, there is often a need to evaluate the threshold to the (longitudinal) microwave instability for a bunched beam in an electron storage ring. Several computational tools are available that allow them, once given the wakefield representing a ring, to numerically find the threshold current and to simulate the development of the instability. In this work, they present results of coputer simulations using two codes recently developed at the SLAC National Accelerator Laboratory: a Vlasov-Fokker-Planck (VFP) solver based on an algorithm by Warnock and Ellison, and a program that find the threshold from the linearized Vlasov equation. They apply the programs to find the instability threshold for three models of ring impedances: that of a Q = 1 resonator, of shielded coherent synchrotron radiation (CSR), and of a resistive wall. The first example is wel-bheaved, but the other two are singular wakes that need special care. Note that similar numerical studies of the threshold of a Q = 1 resonantor wake have been performed by Oide and Yokova, and others. They compare the results of the two programs and discuss their respective capabilities and limitations. In this report they assume the slippage factor {eta} is always positive. They …
Date: August 25, 2010
Creator: Bane, K.L.F.; Cai, Y. & Stupakov, G.
System: The UNT Digital Library
The Complete Four-Loop Four-Point Amplitude in N (open access)

The Complete Four-Loop Four-Point Amplitude in N

We present the complete four-loop four-point amplitude in N = 4 super-Yang-Mills theory, for a general gauge group and general D-dimensional covariant kinematics, and including all non-planar contributions. We use the method of maximal cuts - an efficient application of the unitarity method - to construct the result in terms of 50 four-loop integrals. We give graphical rules, valid in D-dimensions, for obtaining various non-planar contributions from previously-determined terms. We examine the ultraviolet behavior of the amplitude near D = 11/2. The non-planar terms are as well-behaved in the ultraviolet as the planar terms. However, in the color decomposition of the three- and four-loop amplitude for an SU(N{sub c}) gauge group, the coefficients of the double-trace terms are better behaved in the ultraviolet than are the single-trace terms. The results from this paper were an important step toward obtaining the corresponding amplitude in N = 8 supergravity, which confirmed the existence of cancellations beyond those needed for ultraviolet finiteness at four loops in four dimensions. Evaluation of the loop integrals near D = 4 would permit tests of recent conjectures and results concerning the infrared behavior of four-dimensional massless gauge theory.
Date: August 25, 2010
Creator: Bern, Z.; Carrasco, J.J.M.; /UCLA; Dixon, Lance J.; /CERN, /SLAC; Johansson, H. et al.
System: The UNT Digital Library
Complete Genome Sequence of Coraliomargarita Akajimensis Type Strain (04OKA010-24T) (open access)

Complete Genome Sequence of Coraliomargarita Akajimensis Type Strain (04OKA010-24T)

Coraliomargarita akajimensis Yoon et al. 2007 the type species of the genus Coraliomargarita. C. akajimensis is an obligately aerobic, Gram-negative, non-spore-forming, non-motile, spherical bacterium which was isolated from seawater surrounding the hard coral Galaxea fascicularis. C. akajimensis organism is of special interest because of its phylogenetic position in a genomically purely studied area in the bacterial diversity. Here we describe the features of this organism, together with the complete genome sequence, and annotation. This is the first complete genome sequence of a member of the family Puniceicoccaceae. The 3,750,771 bp long genome with its 3,137 protein-coding and 55 RNA genes is a part of the Genomic Encyclopedia of Bacteria and Archaea project.
Date: June 25, 2010
Creator: Mavromatis, Konstantinos; Abt, Birte; Brambilla, Evelyne; Lapidus, Alla; Copeland, Alex; Desphande, Shweta et al.
System: The UNT Digital Library
Complete Genome Sequence of Denitrovibrio Acetiphilus Type Strain (N2460T) (open access)

Complete Genome Sequence of Denitrovibrio Acetiphilus Type Strain (N2460T)

Denitrovibrio acetiphilus Myhr and Torsvik 2000 is the type species of the genus Denitrovibrio in the bacterial family Deferribacteraceae. It is of phylogenetic interest because there are only six genera described in the family Deferribacteraceae. D. acetiphilus was isolated as a representative of a population reducing nitrate to ammonia in a laboratory column simulating the conditions in off-shore oil recovery fields. When nitrate was added to this column undesirable hydrogen sulfide production was stopped because the sulfate reducing populations were superseded by these nitrate reducing bacteria. Here we describe the features of this marine, mesophilic, obligately anaerobic organism respiring by nitrate reduction, together with the complete genome sequence, and annotation. This is the second complete genome sequence of the order Deferribacterales and the class Deferribacteres, which is the sole class in the phylum Deferribacteres. The 3,222,077 bp genome with its 3,034 protein-coding and 51 RNA genes is part of the Genomic Encyclopedia of Bacteria and Archaea project.
Date: June 25, 2010
Creator: Kiss, Hajnalka; Lang, Elke; Lapidus, Alla; Copeland, Alex; Nolan, Matt; Glavina Del Rio, Tijana et al.
System: The UNT Digital Library
CONSIDERATIONS FOR GROUT FORMULATIONS FOR FACILITY CLOSURES USING IN SITU STRATEGIES (open access)

CONSIDERATIONS FOR GROUT FORMULATIONS FOR FACILITY CLOSURES USING IN SITU STRATEGIES

The U.S. Department of Energy (DOE) is conducting in situ closures (entombment) at a large number of facilities throughout the complex. Among the largest closure actions currently underway are the closures of the P and R Reactors at the Savannah River Site (SRS), near Aiken, South Carolina. In these facilities, subgrade open spaces are being stabilized with grout; this ensures the long term structural integrity of the facilities and permanently immobilizes and isolates residual contamination. The large size and structural complexity of these facilities present a wide variety of challenges for the identification and selection of appropriate fill materials. Considerations for grout formulations must account for flowability, long term stability, set times, heat generation and interactions with materials within the structure. The large size and configuration of the facility necessitates that grout must be pumped from the exterior to the spaces to be filled, which requires that the material must retain a high degree of flowability to move through piping without clogging while achieving the required leveling properties at the pour site. Set times and curing properties must be controlled to meet operations schedules, while not generating sufficient heat to compromise the properties of the fill material. The properties of …
Date: August 25, 2010
Creator: Gladden, J.; Serrato, M.; Langton, C.; Long, T.; Blankenship, J.; Hannah, G. et al.
System: The UNT Digital Library
Dalitz-plot Analysis of B0 -> anti-D0 pi pi- (open access)

Dalitz-plot Analysis of B0 -> anti-D0 pi pi-

The authors report preliminary results from a study of the decay B{sup 0} {yields} {bar D}{sup 0}{pi}{sup +}{pi}{sup -} using a data sample of 470.9 {+-} 2.8 million B{bar B} events collected with the BABAR detector at the {Upsilon}(4S) resonance. Using the Dalitz-plot analysis technique, they find contributions from the intermediate resonances D*{sub 2}(2460){sup -}, D*{sub 0}(2400){sup -}, {rho}(770){sup 0} and f{sub 2}(1270) as well as a {pi}{sup +}{pi}{sup -} S-wave term, a {bar D}{sup 0}{pi}{sup -} nonresonant S-wave term and a virtual D*(2010) amplitude. They measure the branching fractions of the contributing decays.
Date: August 25, 2010
Creator: del Amo Sanchez, P.; Lees, J. P.; Poireau, V.; Prencipe, E.; Tisserand, V.; /Annecy, LAPP et al.
System: The UNT Digital Library
Development of a compact neutron source based on field ionization processes (open access)

Development of a compact neutron source based on field ionization processes

The authors report on the use of carbon nanofiber nanoemitters to ionize deuterium atoms for the generation of neutrons in a deuterium-deuterium reaction in a preloaded target. Acceleration voltages in the range of 50-80 kV are used. Field emission of electrons is investigated to characterize the emitters. The experimental setup and sample preparation are described and first data of neutron production are presented. Ongoing experiments to increase neutron production yields by optimizing the field emitter geometry and surface conditions are discussed.
Date: November 25, 2010
Creator: Persaud, Arun; Allen, Ian; Dickinson, Michael R.; Schenkel, Thomas; Kapadia, Rehan; Takei, Kuniharu et al.
System: The UNT Digital Library
Development of Abraham model correlations for solvation characteristics of secondary and branched alcohols (open access)

Development of Abraham model correlations for solvation characteristics of secondary and branched alcohols

This article discusses the development of Abraham model correlations for solvation characteristics of secondary and branched alcohols.
Date: January 25, 2010
Creator: Sprunger, Laura M.; Achi, Sai S.; Pointer, Racheal; Acree, William E. (William Eugene) & Abraham, M. H. (Michael H.)
System: The UNT Digital Library
Development of correlations for describing solute transfer into acyclic alcohol solvents based on the Abraham model and fragment-specific equation coefficients (open access)

Development of correlations for describing solute transfer into acyclic alcohol solvents based on the Abraham model and fragment-specific equation coefficients

This article discusses the development of correlations for describing solute transfer into acyclic alcohol solvents based on the Abraham model and fragment-specific equation coefficients.
Date: January 25, 2010
Creator: Sprunger, Laura M.; Achi, Sai S.; Abraham, M. H. (Michael H.) & Acree, William E. (William Eugene)
System: The UNT Digital Library
A Dual-Moded Cavity for RF Breakdown Studies (open access)

A Dual-Moded Cavity for RF Breakdown Studies

The phenomenon of rf breakdown presents a technological limitation in the application of high-gradient particle acceleration in normal conducting rf structures. Attempts to understand the onset of this phenomenon and to study its limits with different materials, cell shapes, and pulse widths has been driven in recent years by linear collider development. One question of interest is the role magnetic field plays relative to electric field. A design is presented for a single, nonaccelerating, rf cavity resonant in two modes, which, driven independently, allow the rf magnetic field to be increased on the region of highest electric field without affecting the latter. The design allows for the potential reuse of the cavity with different samples in the high-field region. High power data is not yet available.
Date: August 25, 2010
Creator: Nantista, Christopher; /SLAC; Adolphsen, Chris; /SLAC; Wang, Faya & /SLAC
System: The UNT Digital Library
Dynamic Characterization of Mock Explosive Material Using Reverse Taylor Impact Experiments (open access)

Dynamic Characterization of Mock Explosive Material Using Reverse Taylor Impact Experiments

The motivation for the current study is to evaluate the dynamic loading response of an inert mock explosive material used to replicate the physical and mechanical properties of LX-17-1 and PBX 9502 insensitive high explosives. The evaluation of dynamic material parameters is needed for predicting the deformation behavior including the onset of failure and intensity of fragmentation resulting from high velocity impact events. These parameters are necessary for developing and validating physically based material constitutive models that will characterize the safety and performance of energetic materials. The preliminary study uses a reverse Taylor impact configuration that was designed to measure the dynamic behavior of the explosive mock up to and including associated fragmentation. A stationary rod-shaped specimen was impacted using a compressed-gas gun by accelerating a rigid steel anvil attached to a sabot. The impact test employed high-speed imaging and velocity interferometry diagnostics for capturing the transient deformation of the sample at discrete times. Once established as a viable experimental technique with mock explosives, future studies will examine the dynamic response of insensitive high explosives and propellants.
Date: March 25, 2010
Creator: Ferranti, L; Gagliardi, F J; Cunningham, B J & Vandersall, K S
System: The UNT Digital Library
Dynamic Star Formation in the Massive DR21 Filament (open access)

Dynamic Star Formation in the Massive DR21 Filament

The formation of massive stars is a highly complex process in which it is unclear whether the star-forming gas is in global gravitational collapse or an equilibrium state supported by turbulence and/or magnetic fields. By studying one of the most massive and dense star-forming regions in the Galaxy at a distance of less than 3 kpc, i.e. the filament containing the well-known sources DR21 and DR21(OH), we attempt to obtain observational evidence to help us to discriminate between these two views. We use molecular line data from our {sup 13}CO 1 {yields} 0, CS 2 {yields} 1, and N{sub 2}H{sup +} 1 {yields} 0 survey of the Cygnus X region obtained with the FCRAO and CO, CS, HCO{sup +}, N{sub 2}H{sup +}, and H{sub 2}CO data obtained with the IRAM 30m telescope. We observe a complex velocity field and velocity dispersion in the DR21 filament in which regions of the highest column-density, i.e., dense cores, have a lower velocity dispersion than the surrounding gas and velocity gradients that are not (only) due to rotation. Infall signatures in optically thick line profiles of HCO{sup +} and {sup 12}CO are observed along and across the whole DR21 filament. By modelling the observed …
Date: August 25, 2010
Creator: Schneider, N.; Csengeri, T.; Bontemps, S.; Motte, F.; Simon, R.; Hennebelle, P. et al.
System: The UNT Digital Library
Echo-Enabled Harmonic Generation (open access)

Echo-Enabled Harmonic Generation

A recently proposed concept of the Echo-Enabled Harmonic Generation (EEHG) FEL uses two laser modulators in combination with two dispersion sections to generate a high-harmonic density modulation in a relativistic beam. This seeding technique holds promise of a one-stage soft x-ray FEL that radiates not only transversely but also longitudinally coherent pulses. Currently, an experimental verification of the concept is being conducted at the SLAC National Accelerator Laboratory aimed at the demonstration of the EEHG.
Date: August 25, 2010
Creator: Stupakov, Gennady
System: The UNT Digital Library