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SYNTHESIS OF THE FULLY PROTECTED PHOSPHORAMIDITE OF THE BENZENE-DNA ADDUCT, N2- (4-HYDROXYPHENYL)-2'-DEOXYGUANOSINE AND INCORPORATION OF THE LATER INTO DNA OLIGOMERS

Description: N2-(4-Hydroxyphenyl)-2'-deoxyguanosine-5'-O-DMT-3'-phosphoramidite has been synthesized and used to incorporate the N2-(4-hydroxyphenyl)-2'-dG (N2-4-HOPh-dG) into DNA, using solid-state synthesis technology. The key step to obtaining the xenonucleoside is a palladium (Xantphos-chelated) catalyzed N2-arylation (Buchwald-Hartwig reaction) of a fully protected 2'-deoxyguanosine derivative by 4-isobutyryloxybromobenzene. The reaction proceeded in good yield and the adduct was converted to the requi… more
Date: June 9, 2008
Creator: Chenna, Ahmed; Gupta, Ramesh C.; Bonala, Radha R.; Johnson, Francis & Huang, Bo
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Partner: UNT Libraries Government Documents Department
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Structure and Reactions of Carbon and Hydrogen on Ru(0001): A Scanning Tunneling Microscopy Study

Description: The interaction between carbon and hydrogen atoms on a Ru(0001) surface was studied using scanning tunneling microscopy (STM), Density Functional Theory (DFT) and STM image calculations. Formation of CH species by reaction between adsorbed H and C was observed to occur readily at 100 K. When the coverage of H increased new complexes of the form CH+nH (n = 1, 2 and 3) were observed. These complexes, never observed before, might be precursors for further hydrogenation reactions. DFT analysis reve… more
Date: September 9, 2008
Creator: Shimizu, Tomoko K.; Mugarza, Aitor; Cerda, Jorge & Salmeron, Miquel
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Partner: UNT Libraries Government Documents Department
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Toward fully self-consistent simulation of the interaction of E-Clouds and beams with WARP-POSINST

Description: To predict the evolution of electron clouds and their effect on the beam, the high energy physics community has relied so far on the complementary use of 'buildup' and 'single/multi-bunch instability' reduced descriptions. The former describes the evolution of electron clouds at a given location in the ring, or 'station', under the influence of prescribed beams and external fields [1], while the latter (sometimes also referred as the 'quasi-static' approximation [2]) follows the interaction bet… more
Date: April 9, 2012
Creator: Lawrence Livermore National Laboratory
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Partner: UNT Libraries Government Documents Department
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Silver ion mediated shape control of platinum nanoparticles: Removal of silver by selective etching leads to increased catalytic activity

Description: A procedure has been developed for the selective etching of Ag from Pt nanoparticles of well-defined shape, resulting in the formation of elementally-pure Pt cubes, cuboctahedra, or octahedra, with a largest vertex-to-vertex distance of {approx}9.5 nm from Ag-modified Pt nanoparticles. A nitric acid etching process was applied Pt nanoparticles supported on mesoporous silica, as well as nanoparticles dispersed in aqueous solution. The characterization of the silica-supported particles by XRD, TE… more
Date: January 9, 2008
Creator: Grass, Michael E.; Yue, Yao; Habas, Susan E.; Rioux, Robert M.; Teall, Chelsea I. & Somorjai, G.A.
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Partner: UNT Libraries Government Documents Department
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Photofragment Coincidence Imaging of Small I- (H2O)n Clusters Excited to the Charge-transfer-to-solvent State

Description: The photodissociation dynamics of small I{sup -}(H{sub 2}O){sub n} (n = 2-5) clusters excited to their charge-transfer-to-solvent (CTTS) states have been studied using photofragment coincidence imaging. Upon excitation to the CTTS state, two photodissociation channels were observed. The major channel ({approx}90%) is a 2-body process forming neutral I + (H{sub 2}O){sub n} photofragments, and the minor channel is a 3-body process forming I + (H{sub 2}O){sub n-1} + H{sub 2}O fragments. Both proce… more
Date: November 9, 2005
Creator: Neumark, D. E. Szpunar, K. E. Kautzman, A. E. Faulhaber, and D. M.; Kautzman, K.E.; Faulhaber, A.E. & Faulhaber, A.E.
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Partner: UNT Libraries Government Documents Department
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Complete fabrication of target experimental chamber and implement initial target diagnostics to be used for the first target experiments in NDCX-1

Description: The Heavy Ion Fusion Science Virtual National Laboratory (HIFS-VNL) has completed the fabrication of a new experimental target chamber facility for future Warm Dense Matter (WDM) experiments, and implemented initial target diagnostics to be used for the first target experiments in NDCX-1. The target chamber has been installed on the NDCX-I beamline. This achievement provides to the HIFS-VNL unique and state-of-the-art experimental capabilities in preparation for the planned target heating exper… more
Date: June 9, 2008
Creator: Bieniosek, F.M.; Bieniosek, F.M.; Dickinson, M.R.; Henestroza, E.; Katayanagi, T.; Jung, J.Y. et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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X-ray streak camera temporal resolution improvement using a longitudinal time-dependent field

Description: X-ray streak cameras (XSC) have been known to be one of the fastest detectors forultrafast X-ray science. A number of applications in material science, biochemistry, accelerator physics, require sub-picosecond resolution to study new phenomena. Inthis paper, we report on a new method which can potentially improve the temporal resolution of a streak camera down to 100 femtoseconds. This method uses a time-dependent acceleration field to lengthen the photoelectron bunch, significantlyimproving th… more
Date: May 9, 2008
Creator: Qiang, Ji; Qiang, J.; Byrd, J.M.; Feng, J. & Huang, G.
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Partner: UNT Libraries Government Documents Department
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Characterization of a mixed salt of 1-hydroxy-pyridin-2-one Pu(IV)complexes

Description: Most expert analyses of the projected world energy needs show utilization of nuclear energy will be essential for the next few decades, and hence the need to support this technology grows. But as one measure of the supporting science base of this field, as of December 2006, only 25 Pu containing structures were in the Cambridge Structural Database, as compared to 21,807 for Fe. A comparison of the rate of addition to this knowledge base reveals that approximately 500 Fe structures are registere… more
Date: January 9, 2007
Creator: Gorden, Anne E.V.; Xu, Jide; Szigethy, Geza; Oliver, Allen; Shuh,David K. & Raymond, Kenneth N.
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Partner: UNT Libraries Government Documents Department
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Photo-fragmentation of the closo-carboranes Part 1: Energetics of Decomposition

Description: The ionic fragmentation following B 1s and C 1s excitation of three isomeric carborane cage compounds [closo-dicarbadodecaboranes: orthocarborane (1,2-C2B10H12), metacarborane (1,7-C2B10H12), and paracarborane (1,12-C2B10H12)], is compared with the energetics of decomposition. The fragmentation yields for all three molecules are quite similar. Thermodynamic cycles are constructed for neutral and ionic species in an attempt to systemically characterize single ion closo-carborane creation and fra… more
Date: November 9, 2007
Creator: Kilcoyne, Arthur L; Feng, Danqin; Liu, Jing; Hitchcock, Adam P.; Kilcoyne, A.L. David; Tyliszczak, Tolek et al.
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Partner: UNT Libraries Government Documents Department
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Probing the spin polarization of current by soft x-ray imaging of current-induced magnetic vortex dynamics

Description: Time-resolved soft X-ray transmission microscopy is applied to image the current-induced resonant dynamics of the magnetic vortex core realized in a micron-sized Permalloy disk. The high spatial resolution better than 25 nm enables us to observe the resonant motion of the vortex core. The result also provides the spin polarization of the current to be 0.67 {+-} 0.16 for Permalloy by fitting the experimental results with an analytical model in the framework of the spin-transfer torque.
Date: December 9, 2008
Creator: Kasai, Shinya; Fischer, Peter; Im, Mi-Young; Yamada, Keisuke; Nakatani, Yoshinobu; Kobayashi, Kensuke et al.
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Partner: UNT Libraries Government Documents Department
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EXPERIMENTAL PROBLEMS IN THE USE OF A POLARIZED PROTONTARGET

Description: I have understood my assignment as a review of some of the work done in high-energy physics with polarized proton targets and a description of some of the special problems connected with polarized targets. Most of my report will be based on the polarized target that I am most familiar with--that constructed by Jeffries, Schultz, Shapiro, and myself. This target is no longer unique; in fact, it is now somewhat old-fashioned in some respects. Other polarized proton targets are in operation at CER… more
Date: September 9, 1966
Creator: Chamberlain, Owen
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Partner: UNT Libraries Government Documents Department
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On CO2 Behavior in the Subsurface, Following Leakage from a Geologic Storage Reservoir

Description: The amounts of CO2 that would need to be injected intogeologic storage reservoirs to achieve a significant reduction ofatmospheric emissions are very large. A 1000 MWe coal-fired power plantemits approximately 30,000 tonnes of CO2 per day, 10 Mt per year(Hitchon, 1996). When injected underground over a typical lifetime of 30years of such a plant, the CO2 plume may occupy a large area of order 100km2 or more, and fluid pressure increase in excess of 1 bar(corresponding to 10 m water head) may ex… more
Date: February 9, 2006
Creator: Pruess, Karsten
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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TOF Electron Energy Analyzer for Spin and Angular Resolved Photoemission Spectroscopy

Description: Current pulsed laser and synchrotron x-ray sources provide new opportunities for Time-Of- Flight (TOF) based photoemission spectroscopy to increase photoelectron energy resolution and efficiency compared to current standard techniques. The principals of photoelectron timing front formation, temporal aberration minimization, and optimization of electron beam transmission are presented. We have developed these concepts into a high resolution Electron Optical Scheme (EOS) of a TOF Electron Energy … more
Date: July 9, 2008
Creator: Lebedev, Gennadi; Jozwiak, Chris; Andresen, Nord; Lanzara, Alessandra & Hussain, Zahid
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Partner: UNT Libraries Government Documents Department
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Complete chloroplast genome of Trachelium caeruleum: extensiverearrangements are associated with repeats and tRNAs

Description: Chloroplast genome structure, gene order and content arehighly conserved in land plants. We sequenced the complete chloroplastgenome sequence of Trachelium caeruleum (Campanulaceae) a member of anangiosperm family known for highly rearranged chloroplast genomes. Thetotal genome size is 162,321 bp with an IR of 27,273 bp, LSC of 100,113bp and SSC of 7,661 bp. The genome encodes 115 unique genes, with 19duplicated in the IR, a tRNA (trnI-CAU) duplicated once in the LSC and aprotein coding gene (p… more
Date: January 9, 2006
Creator: Haberle, Rosemarie C.; Fourcade, Matthew L.; Boore, Jeffrey L. & Jansen, Robert K.
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Partner: UNT Libraries Government Documents Department
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A Vlasov Solver for Longitudinal Dynamics in Beam Delivery Systems for X-Ray FELs

Description: Direct numerical methods for solving the Vlasov equationoffer some advantages over macroparticle simulations, as they do notsuffer from the consequences of the statistical fluctuations inherent inusing a number of macroparticles smaller than thebunch population.Unfortunately these methods are more time-consuming and generallyconsidered impractical in a full 6D phase space. However, in alower-dimension phase space they may become attractive if the beamdynamics is sensitive to the presence of sma… more
Date: May 9, 2007
Creator: Venturini, Marco; Warnock, Robert & Zholents, Alexander
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Partner: UNT Libraries Government Documents Department
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On macromolecular refinement at subatomic resolution withinteratomic scatterers

Description: A study of the accurate electron density distribution in molecular crystals at subatomic resolution, better than {approx} 1.0 {angstrom}, requires more detailed models than those based on independent spherical atoms. A tool conventionally used in small-molecule crystallography is the multipolar model. Even at upper resolution limits of 0.8-1.0 {angstrom}, the number of experimental data is insufficient for the full multipolar model refinement. As an alternative, a simpler model composed of conv… more
Date: November 9, 2007
Creator: Afonine, Pavel V.; Grosse-Kunstleve, Ralf W.; Adams, Paul D.; Lunin, Vladimir Y. & Urzhumtsev, Alexandre
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Partner: UNT Libraries Government Documents Department
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Field driven ferromagnetic phase nucleation and propagation from the domain boundaries in antiferromagnetically coupled perpendicular anisotropy films

Description: We investigate the reversal process in antiferromagnetically coupled [Co/Pt]{sub X-1}/{l_brace}Co/Ru/[Co/Pt]{sub X-1}{r_brace}{sub 16} multilayer films by combining magnetometry and Magnetic soft X-ray Transmission Microscopy (MXTM). After out-of-plane demagnetization, a stable one dimensional ferromagnetic (FM) stripe domain phase (tiger-tail phase) for a thick stack sample (X=7 is obtained), while metastable sharp antiferromagnetic (AF) domain walls are observed in the remanent state for a th… more
Date: December 9, 2008
Creator: Hauet, Thomas; Gunther, Christian M.; Hovorka, Ondrej; Berger, Andreas; Im, Mi-Young; Fischer, Peter et al.
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Partner: UNT Libraries Government Documents Department
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Elastic Scattering of Low-Energy Electrons byTetrahydrofuran

Description: We present the results of ab initio calculations for elasticelectron scattering by tetrahydrofuran (THF) using the complex Kohnvariational method. We carried out fixed-nuclei calculations at theequilibrium geometry of the target molecule for incident electronenergies up to 20 eV. The calculated momentum transfer cross sectionsclearly reveal the presence of broad shape resonance behavior in the 8-10eV energy range, in agreement with recent experiments. The calculateddifferential cross sections a… more
Date: May 9, 2006
Creator: Trevisan, Cynthia S.; Orel, Ann E. & Rescigno, Thomas N.
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Partner: UNT Libraries Government Documents Department
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Multiscale integration schemes for jump-diffusion systems

Description: We study a two-time-scale system of jump-diffusion stochastic differential equations. We analyze a class of multiscale integration methods for these systems, which, in the spirit of [1], consist of a hybridization between a standard solver for the slow components and short runs for the fast dynamics, which are used to estimate the effect that the fast components have on the slow ones. We obtain explicit bounds for the discrepancy between the results of the multiscale integration method and the … more
Date: December 9, 2008
Creator: Givon, D. & Kevrekidis, I.G.
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Partner: UNT Libraries Government Documents Department
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Thermal effects in plasma-based accelerators

Description: Finite plasma temperature can modify the structure of thewake field, reduce the wave-breaking field, and lead to self-trappedelectrons, which can degrade the electron bunch quality in a plasma-basedaccelerator. A relativistic warm fluid theory is used to describe theplasma temperature evolution and alterations to the structure of anonlinear periodic wave exited in a warm plasma. The trapping thresholdfor a plasma electron and the fraction of electrons trapped from athermal distribution are exam… more
Date: January 9, 2007
Creator: Esarey, E.; Schroeder, C. B.; Michel, E.; Shadwick, B. A.; Geddes, C. G. R. & Leemans, W. P.
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Partner: UNT Libraries Government Documents Department
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Requirements and standards for organelle genome databases

Description: Mitochondria and plastids (collectively called organelles)descended from prokaryotes that adopted an intracellular, endosymbioticlifestyle within early eukaryotes. Comparisons of their remnant genomesaddress a wide variety of biological questions, especially when includingthe genomes of their prokaryotic relatives and the many genes transferredto the eukaryotic nucleus during the transitions from endosymbiont toorganelle. The pace of producing complete organellar genome sequences nowmakes it un… more
Date: January 9, 2006
Creator: Boore, Jeffrey L.
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Partner: UNT Libraries Government Documents Department
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Characteristics of CoxTi1-xO2 thin films deposited by MOCVD

Description: This paper deals with the growth and characterization of ferromagnetic cobalt doped TiO{sub 2} thin films deposited by liquid precursor metal organic chemical vapor deposition (MOCVD) using a new combination of the source materials Co(TMHD){sub 3}, tetrahydrofuran (THF), and titanium isopropoxide (TIP). An array of experiments reveals the intrinsic ferromagnetic nature of the grown films, and suggests that the magnetism is not generated by oxygen vacancies.
Date: May 9, 2008
Creator: McClure, A.; Kayani, A.; Idzerda, Y.U.; Arenholz, E. & Cruz, E.
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Partner: UNT Libraries Government Documents Department
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Improved Spatial Resolution in Thick, Fully-Depleted CCDs withEnhanced Red Sensitivity

Description: The point spread function (PSF) is an important measure of spatial resolution in CCDs for point-like objects, since it affects image quality and spectroscopic resolution. We present new data and theoretical developments for lateral charge diffusion in thick, fully-depleted charge-coupled devices (CCDs) developed at Lawrence Berkeley National Laboratory (LBNL). Because they can be over-depleted, the LBNL devices have no field-free region and diffusion is controlled through the application of an … more
Date: March 9, 2006
Creator: Fairfield, Jessamyn A.; Groom, Donald E.; Bailey, Stephen J.; Bebek, Christopher J.; Holland, Stephen E.; Karcher, Armin et al.
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Partner: UNT Libraries Government Documents Department
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