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Evolution of Primary Hemostasis in Early Vertebrates (open access)

Evolution of Primary Hemostasis in Early Vertebrates

Article on the evolution of primary hemostasis in early vertebrates.
Date: December 23, 2009
Creator: Kim, Seongcheol; Carrillo, Maira; Kulkarni, Vrinda & Jagadeeswaran, Pudur
System: The UNT Digital Library
Dissociation of Water on Defective Carbon Substrates (open access)

Dissociation of Water on Defective Carbon Substrates

Article on the dissociation of water on defective carbon substrates.
Date: September 23, 2005
Creator: Kostov, Milen; Santiso, Erik; George, A. M.; Gubbins, Keith E. & Buongiorno Nardelli, Marco
System: The UNT Digital Library
Collective polarization effects in β-polyvinylidene fluoride and its copolymers with tri- and tetrafluoroethylene (open access)

Collective polarization effects in β-polyvinylidene fluoride and its copolymers with tri- and tetrafluoroethylene

Article on collective polarization effects in β-polyvinylidene fluoride and its copolymers with tri- and tetrafluoroethylene.
Date: September 23, 2005
Creator: Nakhmanson, Serge M.; Buongiorno Nardelli, Marco & Bernholc, Jerry
System: The UNT Digital Library
Mn Interstitial Diffusion in (Ga, Mn)As (open access)

Mn Interstitial Diffusion in (Ga, Mn)As

This article describes a combined theoretical and experimental study of the ferromagnetic semiconductor (Ga, Mn)As which explains the remarkably lard changes observed on low-temperature annealing.
Date: January 23, 2004
Creator: Edmonds, Kevin; Boguslawski, Piotr; Wang, K. Y.; Campion, Richard Paul; Novikov, Sergei; Farley, N. R. S. et al.
System: The UNT Digital Library
Adapting Existing Spatial Data Sets to New Uses: An Example from Energy Modeling (open access)

Adapting Existing Spatial Data Sets to New Uses: An Example from Energy Modeling

Energy modeling and analysis often relies on data collected for other purposes such as census counts, atmospheric and air quality observations, and economic projections. These data are available at various spatial and temporal scales, which may be different from those needed by the energy modeling community. If the translation from the original format to the format required by the energy researcher is incorrect, then resulting models can produce misleading conclusions. This is of increasing importance, because of the fine resolution data required by models for new alternative energy sources such as wind and distributed generation. This paper addresses the matter by applying spatial statistical techniques which improve the usefulness of spatial data sets (maps) that do not initially meet the spatial and/or temporal requirements of energy models. In particular, we focus on (1) aggregation and disaggregation of spatial data, (2) imputing missing data and (3) merging spatial data sets.
Date: June 23, 2006
Creator: Johanesson, G; Stewart, J S; Barr, C; Sabeff, L B; George, R; Heimiller, D et al.
System: The UNT Digital Library
Accurate labeling of the light-actinide O4,5 ionization edges (open access)

Accurate labeling of the light-actinide O4,5 ionization edges

In this short article the accurate labeling of the O4,5 edges of the light actinides is addressed. The O4 and O5 edges are both contained in what is termed the ''giant resonance'' and the smaller ''pre-peak'' that is observed is a consequence of first-order perturbation by the 5d spin-orbit interaction. Thus, the small prepeak in the actinide 5d {yields} 5f transition should not be labeled the O5 peak, but rather the {Delta}S=1 peak.
Date: August 23, 2006
Creator: Moore, K & der Laan, G v
System: The UNT Digital Library
Beyond Boltzmann-Gibbs statistics: Maximum entropy hyperensemblesout-of-equilibrium (open access)

Beyond Boltzmann-Gibbs statistics: Maximum entropy hyperensemblesout-of-equilibrium

What is the best description that we can construct of athermodynamic system that is not in equilibrium, given only one, or afew, extra parameters over and above those needed for a description ofthe same system at equilibrium? Here, we argue the most appropriateadditional parameter is the non-equilibrium entropy of the system, andthat we should not attempt to estimate the probability distribution ofthe system, but rather the metaprobability (or hyperensemble) that thesystem is described by a particular probability distribution. The resultis an entropic distribution with two parameters, one a non-equilibriumtemperature, and the other a measure of distance from equilibrium. Thisdispersion parameter smoothly interpolates between certainty of acanonical distribution at equilibrium and great uncertainty as to theprobability distribution as we move away from equilibrium. We deducethat, in general, large, rare fluctuations become far more common as wemove away from equilibrium.
Date: February 23, 2006
Creator: Crooks, Gavin E.
System: The UNT Digital Library
Multipole Shimming of Permanent Magnets Using Harmonic CorrectorRings (open access)

Multipole Shimming of Permanent Magnets Using Harmonic CorrectorRings

Shimming systems are required to provide sufficient fieldhomogeneity for high resolution NMR. In certain specialized applications,such as rotating-field NMR and portable (ex-situ) NMR, permanentmagnet-based shimming systems can provide considerable advantages. Wepresent a simple two-dimensional shimming method based on harmoniccorrector rings which can provide arbitrary multipole order shimmingcorrections. Results demonstrate, for example, that quadrupolar ordershimming improves the linewidth by up to and order of magnitude. Anadditional order of magnitude reduction is in principle achievable byultilizing this shimming method for z-gradient correction and higherorder xy gradients.
Date: October 23, 2006
Creator: Jachmann, Rebecca C.; Trease, David R.; Bouchard, Louis-S.; Sakellariou, Dimitris; Martin, Rachel W.; Schlueter, Ross D. et al.
System: The UNT Digital Library
Measurement of the Semileptonic Decays B->D tau nu and B->D* tau nu (open access)

Measurement of the Semileptonic Decays B->D tau nu and B->D* tau nu

The authors present measurements of the semileptonic decays B{sup -} {yields} D{sup 0} {tau}{sup -} {bar {nu}}{sub {tau}}, B{sup -} {yields} D*{sup 0} {tau}{sup -}{bar {nu}}{sub {tau}}, {bar B}{sup 0} {yields} D{sup +} {tau}{sup -} {bar {nu}}{sub {tau}}, and {bar B}{sup 0} {yields} D*{sup +} {tau}{sup -}{bar {nu}}{sub {tau}}, which are sensitive to non-Standard Model amplitudes in certain scenarios. The data sample consists of 232 x 10{sup 6} {Upsilon}(4S) {yields} B{bar B} decays collected with the BABAR detector at the PEP-II e{sup +}e{sup -} collider. They select events with a D or D* meson and a light lepton ({ell} = e or {mu}) recoiling against a fully reconstructed B meson. They perform a fit to the joint distribution of lepton momentum and missing mass squared to distinguish signal B {yields} D{sup (*)}{tau}{sup -} {bar {nu}}{sub {tau}} ({tau}{sup -} {yields} {ell}{sup -} {bar {nu}}{sub {ell}}{nu}{sub {tau}}) events from the backgrounds, predominantly B {yields} D{sup (*)} {ell}{sup -}{bar {nu}}{sub {ell}}. They measure the branching-fraction ratios R(D) {triple_bond} {Beta}(B {yields} D{tau}{sup -} {bar {nu}}{sub {tau}})/{Beta}(B {yields} D{ell}{sup -} {bar {nu}}{sub {ell}}) and R(D*) {triple_bond} {Beta}(B {yields} D*{tau}{sup -} {bar {nu}}{sub {tau}})/{Beta}(B {yields} D* {ell}{sup -} {bar {nu}}{sub {ell}}) and, from a combined fit …
Date: February 23, 2009
Creator: Aubert, B.
System: The UNT Digital Library
Target life time of laser ion source for low charge state ion production (open access)

Target life time of laser ion source for low charge state ion production

Laser ion source (LIS) produces ions by irradiating pulsed high power laser shots onto the solid state target. For the low charge state ion production, laser spot diameter on the target can be over several millimeters using a high power laser such as Nd:YAG laser. In this case, a damage to the target surface is small while there is a visible crater in case of the best focused laser shot for high charge state ion production (laser spot diameter can be several tens of micrometers). So the need of target displacement after each laser shot to use fresh surface to stabilize plasma is not required for low charge state ion production. We tested target lifetime using Nd:YAG laser with 5 Hz repetition rate. Also target temperature and vacuum condition were recorded during experiment. The feasibility of a long time operation was verified.
Date: June 23, 2008
Creator: Kanesue,T.; Tamura, J. & Okamura, M.
System: The UNT Digital Library
The effect of head-on beam-beam compensation on the stochastic boundaries and particle diffusion in RHIC. (open access)

The effect of head-on beam-beam compensation on the stochastic boundaries and particle diffusion in RHIC.

To compensate the effects from the head-on beam-beam interactions in the polarized proton operation in the Relativistic Heavy Ion Collider (RHIC), an electron lens (elens) is proposed to collide head-on with the proton beam. We used an extended version of SixTrack for multiparticle beam-beam simulation in order to study the effect of the e-lens on the stochastic boundary and also on diffusion. The stochastic boundary was analyzed using Lyapunov exponents and the diffusion was characterized as the increase in the rms spread of the action. For both studies the simulations were performed with and without the e-lens and with full and partial compensation. Using the simulated values of the diffusion an attempt to calculate the emittance growth rate is presented.
Date: June 23, 2008
Creator: Abreu,N.; Beebe-Wang, J.; FischW; Luo, Y. & Robert-Demolaize, G.
System: The UNT Digital Library
An Experimental Study of Radiation-Induced Demagnetization of Insertion Device Permanent Magnets (open access)

An Experimental Study of Radiation-Induced Demagnetization of Insertion Device Permanent Magnets

High brilliance in the 3GeV new light source NSLS II is obtained from the high magnetic fields in insertion devices (ID). The beam lifetime is limited to 3h by single Coulomb scattering in the Bunch (Touschek effect). This effect occurs everywhere around the circumference and there is unavoidable beam loss in the adjacent low aperture insertion devices. This raises the issue of degradation and damage of the permanent magnetic material by irradiation with high energy electrons and corresponding shower particles. It is expected that IDs, especially those in-vacuum, would experience changes resulting from exposure to gamma rays, x-rays, electrons and neutrons. By expanding an on-going material radiation damage study at BNL the demagnetization effect of irradiation consisting primarily of neutrons, gamma rays and electrons on a set of NdFeB magnets is studied. Integrated doses ranging from several Mrad to a few Grad were achieved at the BNL Isotope Facility with a 112 MeV, 90 {micro}A proton beam. Detailed information on dose distributions as well as on particle energy spectra on the NdFeB magnets was obtained in realistic simulations with the MARS15 Monte-Carlo code. This paper summarizes the results of this study.
Date: June 23, 2008
Creator: Simos,N.; Job, P.K. & Mokhov, N.
System: The UNT Digital Library
An Alternative Model for Electron Correlation in Pu (open access)

An Alternative Model for Electron Correlation in Pu

Using a density functional theory based approach that treats the 5f electrons relativistically, a Pu electronic structure with zero net magnetic moment is obtained, where the 5f orbital and 5f spin moments cancel each other. By combining the spin and orbital specific densities of states with state, spin and polarization specific transition moments, it is possible to reconstruct the experimentally observed photoemission spectra from Pu. Extrapolating to a spin-resolving Fano configuration, it is shown how this would resolve the extant controversy over Pu electronic structure.
Date: October 23, 2007
Creator: Yu, S.; Tobin, J. & Soderlind, P.
System: The UNT Digital Library
Status of the NSLS-II Injection System Design (open access)

Status of the NSLS-II Injection System Design

The NSLS-II is a new ultra-bright 3rd generation 3 GeV light source that will be built at Brookhaven National Laboratory. Its design is well under way. The requirements for the compact injector complex, which will continuously provide 3 GeV electrons for top-off injection into the storage ring, are demanding: high reliability, relatively high charge and low losses. The injector consists of a linear accelerator, a full-energy booster, as well as transport lines, and an injection straight section. In this paper we give an overview of the NSLS-II injector, discuss its status, specifications, and the design challenges.
Date: June 23, 2008
Creator: Shaftan,T.
System: The UNT Digital Library
High-intensity polarized H-(proton), deuteron and 3He++ion source development at BNL. (open access)

High-intensity polarized H-(proton), deuteron and 3He++ion source development at BNL.

New techniques for the production of polarized electron, H{sup -} (proton), D (D+) and {sup 3}H{sup ++} ion beams are discussed. Feasibility studies of these techniques are in progress at BNL. An Optically Pumped Polarized H{sup -} Ion Source (OPPIS) delivers beam for polarization studies in RHIC. The polarized deuteron beam will be required for the deuteron Electron Dipole Moment (EDM) experiment, and the {sup 3}H{sup ++} ion beam is a part of the experimental program for the future eRHIC (Electron Ion) collider.
Date: June 23, 2008
Creator: Zelenski,A.
System: The UNT Digital Library
Setup and performance of RHIC for the 2008 run with deuteron-gold collisions. (open access)

Setup and performance of RHIC for the 2008 run with deuteron-gold collisions.

This year (2008) deuterons and gold ions were collided in the Relativistic Heavy Ion Collider (RHIC) at Brookhaven National Laboratory (BNL) for the first time since 2003. The setup and performance of the collider for the 2008 run is reviewed with a focus on improvements that have led to an order of magnitude increase in luminosity over that achieved in the 2003 run.
Date: June 23, 2008
Creator: Gardner,C.; Abreu, N.P.; Ahren, L.; Alessi, J.; Bai, M. & al., et
System: The UNT Digital Library
Benchmarking of collimation tracking using RHIC beam loss data. (open access)

Benchmarking of collimation tracking using RHIC beam loss data.

State-of-the-art tracking tools were recently developed at CERN to study the cleaning efficiency of the Large Hadron Collider (LHC) collimation system. In order to estimate the prediction accuracy of these tools, benchmarking studies can be performed using actual beam loss measurements from a machine that already uses a similar multistage collimation system. This paper reviews the main results from benchmarking studies performed with specific data collected from operations at the Relativistic Heavy Ion Collider (RHIC).
Date: June 23, 2008
Creator: Robert-Demolaize,G. & Drees, A.
System: The UNT Digital Library
The Reactivity of Energetic Materials At Extreme Conditions (open access)

The Reactivity of Energetic Materials At Extreme Conditions

Energetic materials are unique for having a strong exothermic reactivity, which has made them desirable for both military and commercial applications. Energetic materials are commonly divided into high explosives, propellants, and pyrotechnics. We will focus on high explosive (HE) materials here, although there is a great deal of commonality between the classes of energetic materials. Although the history of HE materials is long, their condensed-phase properties are poorly understood. Understanding the condensed-phase properties of HE materials is important for determining stability and performance. Information regarding HE material properties (for example, the physical, chemical, and mechanical behaviors of the constituents in plastic-bonded explosive, or PBX, formulations) is necessary for efficiently building the next generation of explosives as the quest for more powerful energetic materials (in terms of energy per volume) moves forward. In modeling HE materials there is a need to better understand the physical, chemical, and mechanical behaviors from fundamental theoretical principles. Among the quantities of interest in plastic-bonded explosives (PBXs), for example, are thermodynamic stabilities, reaction kinetics, equilibrium transport coefficients, mechanical moduli, and interfacial properties between HE materials and the polymeric binders. These properties are needed (as functions of stress state and temperature) for the development of improved micro-mechanical …
Date: October 23, 2006
Creator: Fried, L E
System: The UNT Digital Library
Uncoupled achromatic tilted S-bend (open access)

Uncoupled achromatic tilted S-bend

A particular section of the electron beam transport line, to be used in the e-cooling project [l] of the Relativistic Heavy Ion Collider (RHIC), is constrained to displace the trajectory with both horizontal and vertical offsets so that the outgoing beamline is parallel to the incoming beamline. We also require that section be achromatic in both planes. This mixed horizontal and vertical achromatic Sbend is accomplished by rotating the two dipoles and the quadrupoles of the line, about the longitudinal axis of the incoming beam. However such a rotation of the magnetic elements may couple the transported beam through the first order beam transfer matrix (linear coupling). In this paper we study a sufficient condition, that the first order transport matrix (R-matrix) can satisfy, so that this section of beam transfer line is both achromatic and linearly uncoupled. We provide a complete solution for the beam optics which satisfies both conditions.
Date: June 23, 2008
Creator: Tsoupas, N.; Kayran, D.; Litvinenko, V. & MacKay, W. W.
System: The UNT Digital Library
Metastable Supersymmetry Breaking and Multitrace Deformations of SQCD (open access)

Metastable Supersymmetry Breaking and Multitrace Deformations of SQCD

Metastable vacua in supersymmetric QCD in the presence of single and multitrace deformations of the superpotential are explored, with the aim of obtaining an acceptable phenomenology. The metastable vacua appear at one loop, have a broken R-symmetry, and a magnetic gauge group that is completely Higgsed. With only a single trace deformation, the adjoint fermions from the meson superfield are approximately massless at one loop, even though they are massive at tree level and R-symmetry is broken. Consequently, if charged under the standard model, they are unacceptably light. A multitrace quadratic deformation generates fermion masses proportional to the deformation parameter. Phenomenologically viable models of direct gauge mediation can then be obtained, and some of their features are discussed.
Date: February 23, 2009
Creator: Essig, Rouven; Fortin, Jean-Francois; Sinha, Kuver; Torroba, Gonzalo & Strassler, Matthew J.
System: The UNT Digital Library
Multiple-code simulation study of the long-term EDZ evolution of geological nuclear waste repositories (open access)

Multiple-code simulation study of the long-term EDZ evolution of geological nuclear waste repositories

This simulation study shows how widely different model approaches can be adapted to model the evolution of the excavation disturbed zone (EDZ) around a heated nuclear waste emplacement drift in fractured rock. The study includes modeling of coupled thermal-hydrological-mechanical (THM) processes, with simplified consideration of chemical coupling in terms of time-dependent strength degradation or subcritical crack growth. The different model approaches applied in this study include boundary element, finite element, finite difference, particle mechanics, and elastoplastic cellular automata methods. The simulation results indicate that thermally induced differential stresses near the top of the emplacement drift may cause progressive failure and permeability changes during the first 100 years (i.e., after emplacement and drift closure). Moreover, the results indicate that time-dependent mechanical changes may play only a small role during the first 100 years of increasing temperature and thermal stress, whereas such time-dependency is insignificant after peak temperature, because decreasing thermal stress.
Date: October 23, 2008
Creator: Rutqvist, J.; Backstrom, A.; Chijimatsu, M.; Feng, X. T.; Pan, P. Z.; Hudson, J. et al.
System: The UNT Digital Library
SALT FOG TEST OF SAM2X5 COATED STAINLESS STEEL CYLINDER (open access)

SALT FOG TEST OF SAM2X5 COATED STAINLESS STEEL CYLINDER

A salt fog test of an iron-based amorphous metal, SAM2X5, coated Type 316L stainless steel (SS316L) cylinder was made. The cylinder was 30-inch diameter by 88-inch long, and 3/8-inch thick. One end was welded shut with a SS316L end cap before coating. The body of the cylinder and the end cap were both coated. The cylinder was coated with SAM2X5 by the HVOF thermal spray process. The coating thickness was 0.015-inch to 0.019-inch thick. The cylinder was tested in a horizontal position. Also included in the test for reference purposes were five coupons (2-inch x 2-inch x 1/8-inch) of uncoated Type 1018 carbon steel (1018CS). The test used an abbreviated form of GM 9540P. Each cycle was 6 hours in duration and the cylinder and reference samples were exposed to a total of eight cycles. The cylinder was in relatively good condition after the test. Along the body of the cylinder only two pinpoint spot sized signs of rust were seen. The 1018CS reference specimens were extensively rusted.
Date: April 23, 2007
Creator: Aprigliano, L F; Rebak, R B; Choi, J; Lian, T & Day, S D
System: The UNT Digital Library
Dipole magnet for use of RHIC EBIS HEBT line. (open access)

Dipole magnet for use of RHIC EBIS HEBT line.

Construction and magnetic field measurement of dipole magnets for RHIC-EBIS HEBT line have completed. These magnets will be used to guide highly charged ion beams ranging from proton to Uranium provided by a new injector toward the Booster ring in BNL. In this paper, overview of the magnetic design of the dipoles and results of magnetic field measurement are summarized.
Date: June 23, 2008
Creator: Kanesue,T.; Okamura, M.; Ritter, J. & Raparia, D.
System: The UNT Digital Library
Simulating SiD Calorimetry: Software Calibration Procedures and Jet Energy Resolution (open access)

Simulating SiD Calorimetry: Software Calibration Procedures and Jet Energy Resolution

Simulated calorimeter performance in the SiD detector is examined. The software calibration procedures are described, as well as the perfect pattern recognition PFA reconstruction. Performance of the SiD calorimeters is summarized with jet energy resolutions from calorimetry only, perfect pattern recognition and the SiD PFA algorithm. Presented at LCWS08[1]. Our objective is to simulate the calorimeter performance of the SiD detector, with and without a Particle Flow Algorithm (PFA). Full Geant4 simulations using SLIC[2] and the SiD simplified detector geometry (SiD02) are used. In this geometry, the calorimeters are represented as layered cylinders. The EM calorimeter is Si/W, with 20 layers of 2.5mm W and 10 layers of 5mm W, segmented in 3.5 x 3.5mm{sup 2} cells. The HAD calorimeter is RPC/Fe, with 40 layers of 20mm Fe and a digital readout, segmented in 10 x 10mm{sup 2} cells. The barrel detectors are layered in radius, while the endcap detectors are layered in z(along the beam axis).
Date: February 23, 2009
Creator: Cassell, Ron
System: The UNT Digital Library