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X-ray spectroscopic study of the charge state and local orderingof room-temperature ferromagnetic Mn oped ZnO

Description: The charge state and local ordering of Mn doped into a pulsed laser deposited single-phase thin film of ZnO are investigated by using X-ray absorption spectroscopy at the O K-, Mn K- and L-edges, and X-ray emission spectroscopy at the O K- and Mn L-edge. This film is found to be ferromagnetic at room temperature. EXAFS measurement shows that Mn{sup 2+} replaces Zn site in tetrahedral symmetry, and there is no evidence for either metallic Mn or MnO in the film. Upon Mn doping, the top of O 2p va… more
Date: August 7, 2007
Creator: Guo, J.-H.; Gupta, Amita; Sharma, Parmanand; Rao, K.V.; Marcus,M.A.; Dong, C.L. et al.
Partner: UNT Libraries Government Documents Department
open access

Sensitivity study of CO2 storage capacity in brine aquifers withclosed boundaries: Dependence on hydrogeologic properties

Description: In large-scale geologic storage projects, the injected volumes of CO{sub 2} will displace huge volumes of native brine. If the designated storage formation is a closed system, e.g., a geologic unit that is compartmentalized by (almost) impermeable sealing units and/or sealing faults, the native brine cannot (easily) escape from the target reservoir. Thus the amount of supercritical CO{sub 2} that can be stored in such a system depends ultimately on how much pore space can be made available for … more
Date: February 7, 2007
Creator: Zhou, Q.; Birkholzer, J.; Rutqvist, J. & Tsang, C-F.
Partner: UNT Libraries Government Documents Department
open access

Geometrical Properties of a "Snow-Flake" Divertor

Description: Using a simple set of poloidal field coils, one can reach the situation where the null of the poloidal magnetic field in the divertor region is of a second order, not of the first order as in the usual X-point divertor. Then, the separatrix in the vicinity of the null-point splits the poloidal plane not into four sectors, but into six sectors, making the whole structure looking like a snow-flake (whence a name, [1]). This arrangement allows one to spread the heat load over much broader area tha… more
Date: February 7, 2007
Creator: Ryutov, D. D.
Partner: UNT Libraries Government Documents Department
open access

Mixing and CP violation in the D0 and B0(s) systems

Description: Recent developments for mixing and CP violation in the D0 and Bs systems are reviewed, including (i) the recently emerging evidence for D0-D0bar mixing and the interpretations of the measurements; (ii) the theoretical status of the calculations of Delta(Gamma_D) and Delta(m_D); (iii) some implications of the measurement of Bs mixing for new physics.
Date: May 7, 2007
Creator: Ligeti, Zoltan & Ligeti, Zoltan
Partner: UNT Libraries Government Documents Department
open access

COMPARISONS OF CRYSTALLINE SILICOTITANATE AND RESORCINOL FORMALDEHYDE MEDIA FOR CESIUM REMOVAL BY IN-TANK COLUMN PROCESSING

Description: Chemical and thermal performance of crystalline silicotitanate (CST) and resorcinol-formaldehyde (RF) ion exchange media were predicted for column configurations designed for installation in high level waste tanks and intended for cesium removal from radioactive waste supernates. Modeling predictions for the processing of a known Savannah River Site tank waste composition were generated. In a two column configuration under presumed nominal operating conditions (432 gallon packed bed, 10 gpm liq… more
Date: November 7, 2007
Creator: King, W; Frank02 Smith, F; Si Lee, S & Daniel McCabe, D
Partner: UNT Libraries Government Documents Department
open access

Numerical modeling of self-limiting and self-enhancing caprock alteration induced by CO2 storage in a depleted gas reservoir

Description: This paper presents numerical simulations of reactive transport which may be induced in the caprock of an on-shore depleted gas reservoir by the geological sequestration of carbon dioxide. The objective is to verify that CO{sub 2} geological disposal activities currently being planned for the study area are safe and do not induce any undesired environmental impact. In our model, fluid flow and mineral alteration are induced in the caprock by penetration of high CO{sub 2} concentrations from the… more
Date: September 7, 2007
Creator: Xu, Tianfu; Gherardi, Fabrizio; Xu, Tianfu & Pruess, Karsten
Partner: UNT Libraries Government Documents Department
open access

Disruption of Maternal DNA Repair Increases Sperm-DerivedChromosomal Aberrations

Description: The final weeks of male germ cell differentiation occur in aDNA repair-deficient environment and normal development depends on theability of the egg to repair DNA damage in the fertilizing sperm. Geneticdisruption of maternal DNA double-strand break repair pathways in micesignificantly increased the frequency of zygotes with chromosomalstructural aberrations after paternal exposure to ionizing radiation.These findings demonstrate that radiation-induced DNA sperm lesions arerepaired after fertil… more
Date: February 7, 2007
Creator: Marchetti, Francesco; Essers, Jeroun; Kanaar, Roland & Wyrobek,Andrew J.
Partner: UNT Libraries Government Documents Department
open access

Lightest Isotope of Bh Produced Via the 209Bi(52Cr,n)260BhReaction

Description: The lightest isotope of Bh known was produced in the new {sup 209}Bi({sup 52}Cr,n){sup 260}Bh reaction at the Lawrence Berkeley National Laboratory's 88-Inch Cyclotron. Positive identification was made by observation of eight correlated alpha particle decay chains in the focal plane detector of the Berkeley Gas-Filled Separator. {sup 260}Bh decays with a 35{sub -9}{sup +19} ms half-life by alpha particle emission mainly by a group at 10.16 MeV. The measured cross section of 59{sub -20}{sup +29}… more
Date: May 7, 2007
Creator: Nelson, Sarah L.; Gregorich, Kenneth E.; Dragojevic, Irena; Garcia, Mitch A.; Gates, Jacklyn M.; Sudowe, Ralf et al.
Partner: UNT Libraries Government Documents Department
open access

Sensor Development for the Large Synoptic Survey Telescope.

Description: The Large Synoptic Survey project proposes to build an 8m-class ground-based telescope with a dedicated wide field camera. The camera consists of a large focal plane mosaic composed of multi-output CCDs with extended red response. Design considerations and preliminary characterization results for the sensors are presented in this contribution to the Workshop.
Date: June 7, 2007
Creator: O'Connor, P.; Radeka, V. & Takacs, P.
Partner: UNT Libraries Government Documents Department
open access

Interlayer Interaction and Electronic Screening in MultilayerGraphene

Description: The unusual transport properties of graphene are the direct consequence of a peculiar bandstructure near the Dirac point. We determine the shape of the {pi} bands and their characteristic splitting, and find the transition from two-dimensional to bulk character for 1 to 4 layers of graphene by angle-resolved photoemission. By detailed measurements of the {pi} bands we derive the stacking order, layer-dependent electron potential, screening length and strength of interlayer interaction by compar… more
Date: June 7, 2007
Creator: Ohta, Taisuke; Bostwick, Aaron; McChesney, J.L.; Seyller, Thomas; Horn, Karsten & Rotenberg, Eli
Partner: UNT Libraries Government Documents Department
open access

The Extinction Toward the Galactic Bulge from RR Lyrae Stars

Description: The authors present mean reddenings toward 3525 RR0 Lyrae stars from the Galactic bulge fields of the MACHO Survey. These reddenings are determined using the color at minimum V-band light of the RR0 Lyrae stars themselves and are found to be in general agreement with extinction estimates at the same location obtained from other methods. Using 3256 stars located in the Galactic Bulge, they derive the selective extinction coefficient R{sub V,VR} = A{sub V}/E(V-R) = 4.2 {+-} 0.2. this value is wha… more
Date: November 7, 2007
Creator: Kunder, A.; Popowski, P.; Cook, K. & Chaboyer, B.
Partner: UNT Libraries Government Documents Department
open access

Passive Spectroscopy Bolometers, Grating- And X-Ray Imaging Crystal Spectrometers

Description: This tutorial gives a brief introduction into passive spectroscopy and describes the working principles of bolometers, a high-resolution grating spectrometer, and a novel X-ray imaging crystal spectrometer, which is of particular interest for profile measurements of the ion temperature and plasma rotation velocity on ITER and future burning plasma experiments.
Date: November 7, 2007
Creator: Bitter, M.; Hill, K. W.; Scott, S.; Paul, S.; Ince-Cushmann, A.; Reinke, M. et al.
Partner: UNT Libraries Government Documents Department
open access

Molecular Line Emission from Massive Protostellar Disks: Predictions for ALMA and the EVLA

Description: We compute the molecular line emission of massive protostellar disks by solving the equation of radiative transfer through the cores and disks produced by the recent radiation-hydrodynamic simulations of Krumholz, Klein, & McKee. We find that in several representative lines the disks show brightness temperatures of hundreds of Kelvin over velocity channels {approx} 10 km s{sup -1} wide, extending over regions hundreds of AU in size. We process the computed intensities to model the performance o… more
Date: May 7, 2007
Creator: Krumholz, M R; Klein, R I & McKee, C F
Partner: UNT Libraries Government Documents Department
open access

Proton hexality from an anomalous flavor U(1) and neutrino masses--Linking to the string scale

Description: We devise minimalistic gauged U(1)_X Froggatt-Nielsen models which at low-energy give rise to the recently suggested discrete gauge Z_6 symmetry, proton hexality, thus stabilizing the proton. Assuming three generations of right-handed neutrinos, with the proper choice of X-charges, we obtain viable neutrino masses. Furthermore, we find scenarios such that no X-charged hidden sector superfields are needed, which from a bottom-up perspective allows the calculation of g_string, g_X and G_SM's … more
Date: August 7, 2007
Creator: Murayama, Hitoshi; Dreiner, Herbi K.; Luhn, Christoph; Murayama, Hitoshi & Thormeiere, Marc
Partner: UNT Libraries Government Documents Department
open access

TreeQ-VISTA: An Interactive Tree Visualization Tool with Functional Annotation Query Capabilities

Description: Summary: We describe a general multiplatform exploratorytool called TreeQ-Vista, designed for presenting functional annotationsin a phylogenetic context. Traits, such as phenotypic and genomicproperties, are interactively queried from a relational database with auser-friendly interface which provides a set of tools for users with orwithout SQL knowledge. The query results are projected onto aphylogenetic tree and can be displayed in multiple color groups. A richset of browsing, grouping and que… more
Date: May 7, 2007
Creator: Gu, Shengyin; Anderson, Iain; Kunin, Victor; Cipriano, Michael; Minovitsky, Simon; Weber, Gunther et al.
Partner: UNT Libraries Government Documents Department
open access

Interspecific Comparison and annotation of two complete mitochondrial genome sequences from the plant pathogenic fungus Mycosphaerella graminicola

Description: The mitochondrial genomes of two isolates of the wheat pathogen Mycosphaerella graminicola were sequenced completely and compared to identify polymorphic regions. This organism is of interest because it is phylogenetically distant from other fungi with sequenced mitochondrial genomes and it has shown discordant patterns of nuclear and mitochondrial diversity. The mitochondrial genome of M. graminicola is a circular molecule of approximately 43,960 bp containing the typical genes coding for 14 p… more
Date: December 7, 2007
Creator: Millenbaugh, Bonnie A; Pangilinan, Jasmyn L.; Torriani, Stefano F.F.; Goodwin, Stephen B.; Kema, Gert H.J. & McDonald, Bruce A.
Partner: UNT Libraries Government Documents Department
open access

Verification of Gyrokinetic (delta)f Simulations of Electron Temperature Gradient Turbulence

Description: The GEM gyrokinetic {delta}f simulation code [Chen, 2003] [Chen, 2007] is shown to reproduce electron temperature gradient turbulence at the benchmark operating point established in previous work [Nevins, 2006]. The electron thermal transport is within 10% of the expected value, while the turbulent fluctuation spectrum is shown to have the expected intensity and two-point correlation function.
Date: May 7, 2007
Creator: Nevins, W. M.; Parker, S. E.; Chen, Y.; Candy, J.; Dimits, A.; Dorland, W. et al.
Partner: UNT Libraries Government Documents Department
open access

ANALYTICAL METHOD FOR MEASURING TOTAL PROTIUM AND TOTAL DEUTERIUM IN A GAS MIXTURE CONTAINING H2, D2,AND HD VIA GAS CHAROMATOGRAPHY

Description: The most common analytical method of identifying and quantifying non-radioactive isotopic species of hydrogen is mass spectrometry. A low mass, high resolution mass spectrometer with adequate sensitivity and stability to identify and quantify hydrogen isotopes in the low ppm range is an expensive, complex instrument. A new analytical technique has been developed that measures both total protium (H) and total deuterium (D) in a gas mixture containing H{sub 2}, D{sub 2}, and HD using an inexpensi… more
Date: August 7, 2007
Creator: Sessions, H
Partner: UNT Libraries Government Documents Department
open access

Robustness Studies of Ignition Targets for the National Ignition Facility in Two Dimensions

Description: Inertial confinement fusion capsules are critically dependent on the integrity of their hot spots to ignite. At the time of ignition, only a certain fractional perturbation of the nominally spherical hot spot boundary can be tolerated and the capsule still achieve ignition. The degree to which the expected hot spot perturbation in any given capsule design is less than this maximum tolerable perturbation is a measure of the ignition margin or robustness of that design. Moreover, since there will… more
Date: November 7, 2007
Creator: Clark, D S; Haan, S W & Salmonson, J D
Partner: UNT Libraries Government Documents Department
open access

Predictive three dimensional modeling of Stimulated Brillouin Scattering in ignition-scale experiments

Description: The first three-dimensional (3D) simulations of a high power 0.351 {micro}m laser beam propagating through a high temperature hohlraum plasma are reported. We show that 3D linear kinetic modeling of Stimulated Brillouin scattering reproduces quantitatively the experimental measurements, provided it is coupled to detailed hydrodynamics simulation and a realistic description of the laser beam from its millimeter-size envelop down to the micron scale speckles. These simulations accurately predict … more
Date: November 7, 2007
Creator: Divol, L; Berger, R; Meezan, N; Froula, D H; Dixit, S; Suter, L et al.
Partner: UNT Libraries Government Documents Department
open access

Demonstrating fractal scaling of residence time distributions on the catchment scale using a fully-coupled, variably-saturated groundwater and land surface model and a Lagrangian particle tracking approach

Description: The influence of the vadose zone, land surface processes, and macrodispersion on scaling behavior of residence time distributions (RTDs) is studied using a fully coupled watershed model in conjunction with a Lagrangian, particle-tracking approach. Numerical experiments are used to simulate groundwater flow paths from recharge locations along the hillslope to the streambed. These experiments are designed to isolate the influences of topography, vadose zone/land surface processes, and macrodisper… more
Date: November 7, 2007
Creator: Kollet, S J & Maxwell, R M
Partner: UNT Libraries Government Documents Department
open access

The Zeta Potential of Surface-Functionalized Metallic Nanorod Particles in Aqueous Solution

Description: Metallic nanoparticles suspended in aqueous solutions, and functionalized with chemical and biological surface coatings, are important elements in basic and applied nanoscience research. Many applications require an understanding of the electrokinetic or colloidal properties of such particles. In this paper we describe the results of experiments to measure the zeta potential of metallic nanorod particles in aqueous saline solutions, including the effects of pH, ionic strength, metallic composit… more
Date: May 7, 2007
Creator: Dougherty, G M; Rose, K A; Tok, J B; Pannu, S S; Chuang, F S; Sha, M Y et al.
Partner: UNT Libraries Government Documents Department
open access

Fast Electron Generation in Cones with Ultra-Intense Laser Pulses

Description: Experimental results from copper cones irradiated with ultra-intense laser light are presented. Spatial images and total yields of Cu K{sub {alpha}} fluorescence were measured as a function of the laser focusing properties. The fluorescence emission extends into the cone approximately 300 {micro}m from the cone tip and cannot be explained by ray tracing including cone wall absorption. In addition the total fluorescence yield from cones is an order of magnitude higher than for equivalent mass fo… more
Date: December 7, 2007
Creator: Mackinnon, A.; VanWoerkom, L.; Akli, K.; Bartal, T.; Beg, F.; Chawla, S. et al.
Partner: UNT Libraries Government Documents Department
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