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2008

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Articles 11791 - 11820 of 13173

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Theory Of The Piezomagnetic Effect In Mn-Based Antiperovskites, Pavel Lukashev, Renat F. Sabirianov, Kirill D. Belashchenko Jan 2008

Theory Of The Piezomagnetic Effect In Mn-Based Antiperovskites, Pavel Lukashev, Renat F. Sabirianov, Kirill D. Belashchenko

Department of Physics and Astronomy: Faculty Publications

Recent experimental and theoretical studies of the magnetoelectric (ME) effect in the nanocomposite structures and in laminates show an enhanced ME coefficient. These materials combine piezoelectric properties of the paramagnetic phase and piezomagnetic properties of the magnetic phase. We propose to fabricate heterostructures formed by piezoelectric materials and magnetic antiperovskites as magnetoelectric materials. We show that the magnetic structure of antiperovskite, such as Mn3GaN, can be controlled by a small applied biaxial strain. The lowering of symmetry with the strain causes the local magnetic moments of Mn atoms to rotate from the trigonal Γ5g structure with symmetric …

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Relativistic Magnetic Monopole Flux Constraints From Rice, Daniel P. Hogan, Dave Z. Besson, John P. Ralston, Ilya Kravchenko, D. Seckel Jan 2008

Relativistic Magnetic Monopole Flux Constraints From Rice, Daniel P. Hogan, Dave Z. Besson, John P. Ralston, Ilya Kravchenko, D. Seckel

Department of Physics and Astronomy: Faculty Publications

We report an upper limit on the flux of relativistic monopoles based on the nonobservation of in-ice showers by the Radio Ice Cherenkov Experiment (RICE) at the South Pole. We obtain a 95% C.L. limit of order 10-18(cm2 s sr)-1 for intermediate-mass monopoles of 107 ≤ γ ≤ 1012 at the anticipated energy Etot = 1016 GeV. This bound is over an order of magnitude stronger than all previously published experimental limits for this range of boost parameters γ and exceeds 2 orders of magnitude improvement over most of the range. We …

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Thermodynamics Of Itinerant Magnets In A Classical Spin-Fluctuation Model, Aleksander L. Wysocki, James K. Glasbrenner, Kirill D. Belashchenko Jan 2008

Thermodynamics Of Itinerant Magnets In A Classical Spin-Fluctuation Model, Aleksander L. Wysocki, James K. Glasbrenner, Kirill D. Belashchenko

Department of Physics and Astronomy: Faculty Publications

Thermodynamics of itinerant magnets is studied using a classical model with one parameter characterizing the degree of itinerancy. Monte Carlo simulations for bcc and fcc lattices are compared with the mean-field approximation and with the Onsager cavity field approximation extended to itinerant systems. The qualitative features of thermodynamics are similar to the known results of the functional integral method. It is found that magnetic short-range order is weak and almost independent on the degree of itinerancy, and the mean-field approximation describes the thermodynamics reasonably well. Ambiguity of the phase space measure for classical models is emphasized. The Onsager cavity field …

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Aharonov–Bohm Phase Shifts Induced By Laser Pulses, Brett E. Barwick, Herman Batelaan Jan 2008

Aharonov–Bohm Phase Shifts Induced By Laser Pulses, Brett E. Barwick, Herman Batelaan

Department of Physics and Astronomy: Faculty Publications

An experimentally accessible scalar Aharonov–Bohm (AB)-effect is proposed using a ponderomotive potential induced by a pulsed laser. This ponderomotive AB (PAB)-effect is unique in that the time-averaged description is classified as type-I, whereas the underlying time-dependent theory is classified as type-II. Not only is the PAB-effect of fundamental interest, it may also be used to characterize ultrashort electron pulses (fs), using low power femtosecond lasers, which is important for ultrafast electron diffraction and microscopy.

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Tem/Qed Study Of Fept Ultrathin Films And Co/Coo Core-Shell Particles, Xingzhong Li, T. George, X. H. Wei, David J. Sellmyer Jan 2008

Tem/Qed Study Of Fept Ultrathin Films And Co/Coo Core-Shell Particles, Xingzhong Li, T. George, X. H. Wei, David J. Sellmyer

David Sellmyer Publications

Transmission electron microscopy (TEM) imaging and electron diffraction (ED) techniques are widely used in the studies of thin films and nanoparticles. Although various advanced techniques have been well established, such as high-resolution electron microscopy (HREM) and convergent beam electron diffraction (CBED), the conventional TEM imaging and selected-area electron diffraction (SAED) techniques remain the essential methods for microstructure and crystal structure characterization. Digital TEM image processing and quantitative ED analysis (QED) has become one trend for improvements. Recently computer programs [1,2] have been developed for analysis of SAED patterns of polycrystalline phases. In this paper, we report the preliminary results on …

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Charge Order, Dynamics, And Magnetostructural Transition In Multiferroic Lufe2o4, X. S. Xu, M. Angst, T. V. Brinzari, R. P. Hermann, J. L. Musfeldt, A. D. Christianson, D. Mandrus, B. C. Sales, S. Mcgill, J. -W. Kim, Z. Islam Jan 2008

Charge Order, Dynamics, And Magnetostructural Transition In Multiferroic Lufe2o4, X. S. Xu, M. Angst, T. V. Brinzari, R. P. Hermann, J. L. Musfeldt, A. D. Christianson, D. Mandrus, B. C. Sales, S. Mcgill, J. -W. Kim, Z. Islam

Xiaoshan Xu Papers

We investigated the series of temperature and field-driven transitions in LuFe2O4 by optical and Mossbauer spectroscopies, magnetization, and x-ray scattering in order to understand the interplay between charge, structure, and magnetism in this multiferroic material. We demonstrate that charge fluctuation has an onset well below the charge ordering transition, supporting the ‘‘order by fluctuation’’ mechanism for the development of charge order superstructure. Bragg splitting and large magneto-optical contrast suggest a low-temperature monoclinic distortion that can be driven by both temperature and magnetic field.

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Measurements Of The Gvd Of Water And Methanol And Laser Pulse Characterization Using Direct Imaging Methods, Timothy Scarborough, Chad Petersen, Cornelis J. Uiterwaal Jan 2008

Measurements Of The Gvd Of Water And Methanol And Laser Pulse Characterization Using Direct Imaging Methods, Timothy Scarborough, Chad Petersen, Cornelis J. Uiterwaal

C.J.G.J. Uiterwaal Publications

We report experimental values of the group velocity dispersion (GVD) of water and methanol at 800 nm. We find GVDwater 800 = (25.71± 0.5) fs2 mm−1 and GVDmethanol 800 = (33.56±0.5) fs2 mm-1. These were measured by sending 50 fs, 800 nm pulses with various amounts of chirp through a glass cell filled with a solution of fluorescein in these solvents and recording the production of visible light from the side using a commercial digital camera. This simple setup also gives quantitative information on the duration of our pulses and lets us check …

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Nicarbazin Bait Reduces Reproduction By Pigeons (Columba Livia), Michael L. Avery, Kandy L. Keacher, Eric A. Tillman Jan 2008

Nicarbazin Bait Reduces Reproduction By Pigeons (Columba Livia), Michael L. Avery, Kandy L. Keacher, Eric A. Tillman

United States Department of Agriculture Wildlife Services: Staff Publications

Development of effective methods for reducing populations of overabundant nuisance bird species continues to challenge wildlife biologists. Reproductive inhibition, although conceptually pleasing, has been difficult to implement because of the lack of a safe, approved avian contraceptive. Recently, however, nicarbazin received regulatory approval in the United States for use as a bait to decrease hatchability of resident Canada goose (Branta canadensis) and feral pigeon (Columba livia) eggs. In anticipation of the feral pigeon registration, we evaluated efficacy by exposing captive pairs of nesting pigeons to nicarbazin bait for 4 h daily. Egg production was unaffected, but …

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Evaluation Of Aerial Cluster Sampling Of Double-Crested Cormorants On Aquaculture Ponds In Mississippi, Brian S. Dorr, Loren W. Burger Jr., Scott C. Barras Jan 2008

Evaluation Of Aerial Cluster Sampling Of Double-Crested Cormorants On Aquaculture Ponds In Mississippi, Brian S. Dorr, Loren W. Burger Jr., Scott C. Barras

United States Department of Agriculture Wildlife Services: Staff Publications

Concern over increasing numbers of double-crested cormorants (Phalacrocorax auritus) and their impacts on channel catfish (Ictalurus punctatus) aquaculture has resulted in increased need for quantitative information to develop and evaluate depredation management efforts. We evaluated aerial surveys in a stratified cluster sampling (SCS) design to estimate and monitor abundance of cormorants on catfish aquaculture ponds in the Yazoo River Basin of Mississippi, USA (hereafter Yazoo Basin). Twice monthly abundance estimates and coefficient of variation during winter averaged 8,128 (n = 29, SE = 1,233) and 33% (n = 29, SE = 0.02), respectively. Counts of cormorants …

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Bioaccumulation Of Pharmaceuticals And Other Anthropogenic Waste Indicators In Earthworms From Agricultural Soil Amended With Biosolid Or Swine Manure, Chad Kinney, Edward Furlong, Dana Kolpin, Mark Burkhardt, Steven Zaugg, Stephen Werner, Joseph Bossio, Mark Benotti Jan 2008

Bioaccumulation Of Pharmaceuticals And Other Anthropogenic Waste Indicators In Earthworms From Agricultural Soil Amended With Biosolid Or Swine Manure, Chad Kinney, Edward Furlong, Dana Kolpin, Mark Burkhardt, Steven Zaugg, Stephen Werner, Joseph Bossio, Mark Benotti

United States Geological Survey: Staff Publications

Analysis of earthworms offers potential for assessing the transfer of organic anthropogenic waste indicators (AWIs) derived from land-applied biosolid or manure to biota. Earthworms and soil samples were collected from three Midwest agricultural fields to measure the presence and potential for transfer of 77 AWIs from land-applied biosolids and livestock manure to earthworms. The sites consisted of a soybean field with no amendments of human or livestock waste (Site 1), a soybean field amended with biosolids from a municipal wastewater treatment plant (Site 2), and a cornfield amended with swine manure (Site 3). The biosolid applied to Site 2 contained …

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Foot-And-Mouth Disease In North American Bison (Bison Bison) And Elk (Cervus Elaphus Nelsoni): Susceptibility, Intra- And Interspecies Transmission, Clinical Signs, And Lesions, Jack Rhyan, Ming Deng, He Wang, Gordon Ward, Thomas Gidlewski, Matthew Mccollum, Samia Metwally, Thomas Mckenna, Sherrilyn Wainwright, Antonio Ramirez, Charles Mebus, Mo Salman Jan 2008

Foot-And-Mouth Disease In North American Bison (Bison Bison) And Elk (Cervus Elaphus Nelsoni): Susceptibility, Intra- And Interspecies Transmission, Clinical Signs, And Lesions, Jack Rhyan, Ming Deng, He Wang, Gordon Ward, Thomas Gidlewski, Matthew Mccollum, Samia Metwally, Thomas Mckenna, Sherrilyn Wainwright, Antonio Ramirez, Charles Mebus, Mo Salman

United States Department of Agriculture Wildlife Services: Staff Publications

There is limited information about the pathogenesis and epidemiology of foot-andmouth disease (FMD) in North American bison (Bison bison) or elk (Cervus elaphus nelsoni). In these two experimental infection studies, we compared the susceptibilities of bison and elk to FMD virus (FMDV), respectively, with that of cattle; determined whether intra- and interspecies transmission could occur in bison and cattle, and elk and cattle; determined suitability of conventional available laboratory tests to detect FMDV infection in bison and elk; and investigated whether bison or elk are efficient long-term carriers of FMDV. In both studies, after a period …

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Geochemical Evidence For Airborne Dust Additions To Soils In Channel Islands National Park, California, Daniel R. Muhs, James R. Budahn, Donald L. Johnson, Marith Reheis, Jossh Beann, Gary Skipp, Eric Fischer, Julia A. Jones Jan 2008

Geochemical Evidence For Airborne Dust Additions To Soils In Channel Islands National Park, California, Daniel R. Muhs, James R. Budahn, Donald L. Johnson, Marith Reheis, Jossh Beann, Gary Skipp, Eric Fischer, Julia A. Jones

United States Geological Survey: Staff Publications

There is an increasing awareness that dust plays important roles in climate change, biogeochemical cycles, nutrient supply to ecosystems, and soil formation. In Channel Islands National Park, California, soils are clay-rich Vertisols or Alfi sols and Mollisols with vertic properties. The soils are overlain by silt-rich mantles that contrast sharply with the underlying clay-rich horizons. Silt mantles contain minerals that are rare or absent in the volcanic rocks that dominate these islands. Immobile trace elements (Sc-Th-La and Ta-Nd-Cr) and rare-earth elements show that the basalt and andesite on the islands have a composition intermediate between upper-continental crust and oceanic crust. …

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Isotopic Evidence For The Diversity Of Late Quaternary Loess In Nebraska: Glaciogenic And Nonglaciogenic Sources, John N. Aleinikoff, Daniel R. Muhs, E. Arthur Bettis Iii, William C. Johnson, C. Mark Fanning, Rachel Benton Jan 2008

Isotopic Evidence For The Diversity Of Late Quaternary Loess In Nebraska: Glaciogenic And Nonglaciogenic Sources, John N. Aleinikoff, Daniel R. Muhs, E. Arthur Bettis Iii, William C. Johnson, C. Mark Fanning, Rachel Benton

United States Geological Survey: Staff Publications

Pb isotope compositions of detrital K-feldspars and U-Pb ages of detrital zircons are used as indicators for determining the sources of Peoria Loess deposited during the last glacial period (late Wisconsin, ca. 25–14 ka) in Nebraska and western Iowa. Our new data indicate that only loess adjacent to the Platte River has Pb isotopic characteristics suggesting derivation from this river. Most Peoria Loess in central Nebraska (up to 20 m thick) is non-glaciogenic, on the basis of Pb isotope ratios in K-feldspars and the presence of 34-Ma detrital zircons. These isotopic characteristics suggest derivation primarily from the Oligocene White River …

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Origin And Paleoclimatic Significance Of Late Quaternary Loess In Nebraska: Evidence From Stratigraphy, Chronology, Sedimentology, And Geochemistry, Daniel R. Muhs, E. Arthur Bettis Iii, John N. Aleinikoff, John P. Mcgeehin, Jossh Beann, Gary Skipp, Brian D. Marshall, Helen M. Roberts, William C. Johnson, Rachel Benton Jan 2008

Origin And Paleoclimatic Significance Of Late Quaternary Loess In Nebraska: Evidence From Stratigraphy, Chronology, Sedimentology, And Geochemistry, Daniel R. Muhs, E. Arthur Bettis Iii, John N. Aleinikoff, John P. Mcgeehin, Jossh Beann, Gary Skipp, Brian D. Marshall, Helen M. Roberts, William C. Johnson, Rachel Benton

United States Geological Survey: Staff Publications

Loess is one of the most extensive surficial geologic deposits in mid-continental North America, particularly in the central Great Plains region of Nebraska. Last-glacial-age loess (Peoria Loess) reaches its greatest known thickness in the world in this area. New stratigraphic, geochronologic, mineralogic, and geochemical data yield information about the age and provenance of Peoria Loess, as well as evaluation of recent climate models.

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Web-Based Applications For Building, Managing And Analysing Kinetic Models Of Biological Systems, Dong-Yup Lee, Rajib Saha, Faraaz Noor Khan Yusufi, Wonjun Park, Iftekhara. Karimi Jan 2008

Web-Based Applications For Building, Managing And Analysing Kinetic Models Of Biological Systems, Dong-Yup Lee, Rajib Saha, Faraaz Noor Khan Yusufi, Wonjun Park, Iftekhara. Karimi

Department of Chemical and Biomolecular Engineering: Faculty Publications

Mathematical modelling and computational analysis play an essential role in improving our capability to elucidate the functions and characteristics of complex biological systems such as metabolic, regulatory and cell signalling pathways. The modelling and concomitant simulation render it possible to predict the cellular behaviour of systems under various genetically and/or environmentally perturbed conditions. This motivates systems biologists/bioengineers/ bioinformaticians to develop new tools and applications, allowing non-experts to easily conduct such modelling and analysis.However, among a multitude of systems biology tools developed to date, only a handful of projects have adopted a web-based approach to kinetic modelling. In this report, we …

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Performance Evaluation Of Aluminum Test Cell Designed For Determining The Heat Resistance Of Bacterial Spores In Foods, H.-J. Chung, Sohan Birla, Juming Tang Jan 2008

Performance Evaluation Of Aluminum Test Cell Designed For Determining The Heat Resistance Of Bacterial Spores In Foods, H.-J. Chung, Sohan Birla, Juming Tang

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Thermal inactivation kinetic studies are necessary to determine heat resistances of spores in the development of new thermal processes for low-acid shelf-stable products. Most currently available sample holders used in the kinetic studies take long time to reach the target sample temperature, hence fail to provide isothermal condition. In this research, novel aluminum test cells were developed to facilitate easy loading and unloading solid and liquid food samples in a hermetically sealed 1 ml cavity to evaluate the heat resistance of bacterial spores when heated at temperatures above 100 °C. Design of the test cell was governed by minimum come-up …

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Characterization Of Radio Frequency Heating Of Fresh Fruits Influenced By Dielectric Properties, Sohan Birla, S. Wang, Juming Tang, G. Tiwari Jan 2008

Characterization Of Radio Frequency Heating Of Fresh Fruits Influenced By Dielectric Properties, Sohan Birla, S. Wang, Juming Tang, G. Tiwari

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Because of its fast and volumetric nature, radio frequency (RF) heating has been looked upon as a way to overcome the problems associated with conventional heating methods used for disinfestation of fruits. But non-uniform heating within fruits is a major obstacle in adaptation of this technology. In this study, RF heating patterns influenced by dielectric properties (DPs) of fruits were investigated both experimentally and mathematically. A computer simulation model was developed using FEMLAB 3.4, a commercial software for solving Maxwell’s electromagnetic and Fourier’s heat transfer equations. Orange, apple, grapefruit, peach, and avocado fruits, selected for these studies were subjected to …

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A Highly Conserved Family Of Inactivated Archaeal B Family Dna Polymerases, Igor Rogozin, Kira Makarova, Youri Pavlov, Eugene Koonin Jan 2008

A Highly Conserved Family Of Inactivated Archaeal B Family Dna Polymerases, Igor Rogozin, Kira Makarova, Youri Pavlov, Eugene Koonin

Papers in Evolution

A widespread and highly conserved family of apparently inactivated derivatives of archaeal B-family DNA polymerases is described. Phylogenetic analysis shows that the inactivated forms comprise a distinct clade among archaeal B-family polymerases and that, within this clade, Euryarchaea and Crenarchaea are clearly separated from each other and from a small group of bacterial homologs. These findings are compatible with an ancient duplication of the DNA polymerase gene followed by inactivation and parallel loss in some of the lineages although contribution of horizontal gene transfer cannot be ruled out. The inactivated derivative of the archaeal DNA polymerase could form a complex …

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Management Recommendations Based On Matrix Projection Models: The Importance Of Considering Biological Limits, Joan Lubben, Brigitte Tenhumberg, Andrew J. Tyre, Richard Rebarber Jan 2008

Management Recommendations Based On Matrix Projection Models: The Importance Of Considering Biological Limits, Joan Lubben, Brigitte Tenhumberg, Andrew J. Tyre, Richard Rebarber

School of Biological Sciences: Faculty Publications

Matrix population models are a common tool for evaluating different management strategies. In general, under deterministic analyses, management strategies are recommended that improve those matrix transitions that are most sensitive or elastic with respect to the asymptotic population growth rate, λ. These recommendations usually ignore the biological limit for these transitions. In this paper we use the endangered Serengeti cheetah (Acinonyx jubatus) as a case study to illustrate that ignoring biological limits leads to a recommendation that will not always achieve the desired goal of an asymptotic population growth rate, λ ≥ 1. We estimate the survivorships of …

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Proposed Method For Measuring The Duration Of Electron Pulses By Attosecond Streaking, Peter Reckenthaeler, Martin Centurion, V. S. Yakovlev, M. Lezius, F. Krausz, Ernst E. Fill Jan 2008

Proposed Method For Measuring The Duration Of Electron Pulses By Attosecond Streaking, Peter Reckenthaeler, Martin Centurion, V. S. Yakovlev, M. Lezius, F. Krausz, Ernst E. Fill

Martin Centurion Publications

We propose a method to measure the duration of ultrashort electron pulses. The electron pulse to be measured impinges on a solid target, causing the emission of Auger electrons through impact ionization. The energy spectrum of the Auger electrons is altered in the presence of an intense femtosecond laser field. Due to the extremely short lifetime of the Auger effect, this effect can be used to generate cross correlation between a laser and an electron pulse. The method is applicable to electron pulses ranging from hundreds of attoseconds to hundreds of femtoseconds in duration, and for a few hundreds of …

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Unoccupied Orbital Energies Of 1,4-Benzenedithiol And The Homo–Lumo Gap, Adam M. Scheer, Gordon A. Gallup, Paul Burrow Jan 2008

Unoccupied Orbital Energies Of 1,4-Benzenedithiol And The Homo–Lumo Gap, Adam M. Scheer, Gordon A. Gallup, Paul Burrow

Paul Burrow Publications

The energies of the temporary anion states of 1,4-benzenedithiol (BDT) are determined by electron scattering and compared with those computed by density functional theory (DFT) and Hartree–Fock (HF) methods. Using semi-empirical scalings derived from the ionization energies and electron affinities of a series of phenyl–ethynyl compounds, we compute the HOMO–LUMO energy gap of BDT. We show that without such scalings the gap is substantially underestimated using DFT and overestimated using HF methods. Scaled gaps are also determined for several related compounds and compared with experimental measurements in the literature.

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Are There Π* Shape Resonances In Electron Scattering From Phosphate Groups?, Paul Burrow, Gordon A. Gallup, Alberto Modelli Jan 2008

Are There Π* Shape Resonances In Electron Scattering From Phosphate Groups?, Paul Burrow, Gordon A. Gallup, Alberto Modelli

Paul Burrow Publications

The temporary anion states of trimethyl phosphate and several compounds bearing the P=O group were explored using electron transmission spectroscopy and ab initio calculations to determine if these states have the characteristics of the π* resonances usually associated with multiple bonds. No evidence was found for this in (CH3O)3PO and, by extension, we do not expect them to appear in the phosphate group of DNA. Cl3PO, however, does display such characteristics to some extent, and we show that they arise from the spatial properties of the π* (P-Cl) orbitals rather than from multiple PO …

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Oligo(Vinylidene Fluoride) Langmuir-Blodgett Films Studied By Spectroscopic, Rafal Korlacki, J. Travis Johnston, Jihee Kim, Stephen Ducharme, Daniel W. Thompson, Vladimir M. Fridkin, Zhongxin Ge, James M. Takacs Jan 2008

Oligo(Vinylidene Fluoride) Langmuir-Blodgett Films Studied By Spectroscopic, Rafal Korlacki, J. Travis Johnston, Jihee Kim, Stephen Ducharme, Daniel W. Thompson, Vladimir M. Fridkin, Zhongxin Ge, James M. Takacs

Stephen Ducharme Publications

Thin films of amphiphilic vinylidene fluoride oligomers prepared by Langmuir–Blodgett deposition on silicone substrates were investigated by comparing experimental and theoretical mid-infrared (IR) spectra. The experimental spectra were obtained using infrared spectroscopic ellipsometry. Theoretical spectra were calculated using density functional theory. Excellent correspondence of major IR bands in both data sets shows that the molecular backbone is oriented with the long axis normal to the substrate plane. This is in contrast to poly vinylidene fluoride[1] LB films, in which the polymer chains are parallel to the substrate.

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The Kinetic Energy Dependent Effective Debye Temperature For Cos2 (100), Ning Wu, David Wisbey, Takashi Komesu, Z. X. Yu, M. Manno, L. Wang, C. Leighton, Peter A. Dowben Jan 2008

The Kinetic Energy Dependent Effective Debye Temperature For Cos2 (100), Ning Wu, David Wisbey, Takashi Komesu, Z. X. Yu, M. Manno, L. Wang, C. Leighton, Peter A. Dowben

Peter Dowben Publications

The effective Debye temperatures of the highly spin-polarized material CoS2 were measured using temperature dependent low energy electron diffraction and shown to be dependent upon electron kinetic energy. The normal dynamic motion of the (100) surface results in the effective surface Debye temperature of 326 ± 9 K compared to a bulk Debye temperature of 612 ± 24 K. Similar values for the bulk Debye temperature have been obtained through LEED I(V) analysis, core level photoemission with a lower value for the bulk Debye temperature found from heat capacity measurements.

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Search For The Lightest Scalar Top Quark In Events With Two Leptons In Pp Collisions At √S = 1.96 Tev, V. M. Abazov, Kenneth A. Bloom, Gregory Snow, D0 Collaboration Jan 2008

Search For The Lightest Scalar Top Quark In Events With Two Leptons In Pp Collisions At √S = 1.96 Tev, V. M. Abazov, Kenneth A. Bloom, Gregory Snow, D0 Collaboration

Kenneth Bloom Publications

Data collected by the D0 detector at a pp center-of-mass energy of 1.96 TeV at the Fermilab Tevatron Collider have been used to search for pair production of the lightest supersymmetric partner of the top quark decaying into bℓν. The search is performed in the ℓℓ′ = eμ and μμ final states. No evidence for this process has been found in data samples of approximately 400 pb-1. The domain in the [M(t1),M(ν)] plane excluded at the 95% C.L. is substantially extended by this search.

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Interface-Induced Spin And Dipole Ordering Of The Copper Spin ½ Molecule: Bis(4-Cyano-2,2,6,6-Tetramethyl-3,5-Heptanedionato)Copper(Ii), David Wisbey, Ning Wu, Danqin Feng, Anthony N. Caruso, John Belot, Yaroslav B. Losovyj, Elio Vescovo, Peter A. Dowben Jan 2008

Interface-Induced Spin And Dipole Ordering Of The Copper Spin ½ Molecule: Bis(4-Cyano-2,2,6,6-Tetramethyl-3,5-Heptanedionato)Copper(Ii), David Wisbey, Ning Wu, Danqin Feng, Anthony N. Caruso, John Belot, Yaroslav B. Losovyj, Elio Vescovo, Peter A. Dowben

Peter Dowben Publications

Using light-polarization-dependent angle-resolved photoemission, the metal-organic molecule bis(4-cyano- 2,2,6,6-tetramethyl-3,5-heptanedionato)copper(II) (or Cu(CNdpm)2, i.e., C24H36N2O4Cu, Cu(II)) is observed to adopt a preferential orientation that depends on the film thickness and substrate when adsorbed on Co(111) and Cu(111). In addition, the final-state binding energies change with film thickness, suggesting the substrates affect the screening or charging in the photoemission final state. For Cu(CNdpm)2 deposited on Co(111), the induced spin polarization was found to depend strongly on the molecular orbital contributions.

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The Surface Stability Of Cos2(100), Ning Wu, Renat F. Sabirianov, Chun-Gang Duan, Wai-Ning Mei, David Wisbey, Yaroslav B. Losovyj, M. Manno, C. Leighton, En Cai, Jiandi Zhang, Peter A. Dowben Jan 2008

The Surface Stability Of Cos2(100), Ning Wu, Renat F. Sabirianov, Chun-Gang Duan, Wai-Ning Mei, David Wisbey, Yaroslav B. Losovyj, M. Manno, C. Leighton, En Cai, Jiandi Zhang, Peter A. Dowben

Peter Dowben Publications

The stability of various possible terminations of the CoS2 (1 × 1) surface have been explored and theoretical expectations are found to agree with experiment. With extensive annealing, there is a phase separation at the (100) surface of CoS2. Sulfur segregation to the surface leads to a significant change in the largely sulfur bands due to changes in the hybridized bands, with cobalt. Resonant photoemission spectra indicate clearly that the hybridized cobalt and sulfur bands, characteristic of the CoS2 bulk, lie at higher binding energies than those of segregated sulfur layers. This is discussed in terms …

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The Cms Experiment At The Cern Lhc, S. Chatrchyan, Kenneth A. Bloom, Brian Bockelman, Daniel R. Claes, Aaron Dominguez, Michael Eads, Makoto Furukawa, J. Keller, T. Kelly, Carl Lundstedt, Sudhir Malik, Gregory Snow, David R. Swanson, Cms Collaboration Jan 2008

The Cms Experiment At The Cern Lhc, S. Chatrchyan, Kenneth A. Bloom, Brian Bockelman, Daniel R. Claes, Aaron Dominguez, Michael Eads, Makoto Furukawa, J. Keller, T. Kelly, Carl Lundstedt, Sudhir Malik, Gregory Snow, David R. Swanson, Cms Collaboration

Kenneth Bloom Publications

The Compact Muon Solenoid (CMS) detector is described. The detector operates at the Large Hadron Collider (LHC) at CERN. It was conceived to study proton-proton (and leadlead) collisions at a centre-of-mass energy of 14 TeV (5.5 TeV nucleon-nucleon) and at luminosities up to 1034 cm-2s-1 (1027 cm-2s-1). At the core of the CMS detector sits a high-magnetic field and large-bore superconducting solenoid surrounding an all-silicon pixel and strip tracker, a lead-tungstate scintillating-crystals electromagnetic calorimeter, and a brass-scintillator sampling hadron calorimeter. The iron yoke of the flux-return is instrumented with four stations …

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Temperature Dependence Of The Training Effect In Exchange Coupled Ferromagnetic Bilayers, Srinivas Polisetty, Sarbeswar Sahoo, Andreas Berger, Christian Binek Jan 2008

Temperature Dependence Of The Training Effect In Exchange Coupled Ferromagnetic Bilayers, Srinivas Polisetty, Sarbeswar Sahoo, Andreas Berger, Christian Binek

Christian Binek Publications

The temperature dependence of the training effect is studied in an exchange coupled thin-film bilayer composed of a hard ferromagnetic pinning (CoPtCrB) layer in proximity of a soft ferromagnetic pinned (CoCr) layer. Interlayer exchange shifts the hysteresis loops of the soft layer along the magnetic-field axis. This shift is quantified by the bias field in far reaching analogy to the exchange bias field of conventional antiferromagnetic/ferromagnetic heterostructures. A ferromagnetic domain state induced in the hard layer experiences aging very similar to the training behavior of the antiferromagnetic domain state in conventional exchange bias systems. Training originates from changes in the …

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Development Of Truck Weight Limits For Concrete Bridges Using Reliability Theory Desenvolvimento De Equações Para A Limitação Do Peso De Veículos De Carga Em Pontes De Concreto Através Da Teoria De Confiabilidade, L. M. Ferreira, A. S. Nowak, M. K. El Debs Jan 2008

Development Of Truck Weight Limits For Concrete Bridges Using Reliability Theory Desenvolvimento De Equações Para A Limitação Do Peso De Veículos De Carga Em Pontes De Concreto Através Da Teoria De Confiabilidade, L. M. Ferreira, A. S. Nowak, M. K. El Debs

Department of Civil and Environmental Engineering: Faculty Publications

The increase in gross weight limits allowed by Brazilian legislation and the soaring number of new truck configurations on national highways has called for greater attention regarding the structural safety of bridges when submitted to real traffic. This paper verifies the performance of bridges under Sao Paulo Department of Transportation jurisdiction using the reliability index β and obtains truck weight limits in order to guarantee structural integrity. The superstructures of reinforced and prestressed concrete bridges, classes 36 and 45, are considered. The ultimate limit state is verified in cross sections subjected to positive and negative critical bending moments. In case …

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