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Selective extraction of copper, mercury, silver and palladium ionsfrom water using hydrophobic ionic liquids.

Description: Extraction of dilute metal ions from water was performed near room temperature with a variety of ionic liquids. Distribution coefficients are reported for fourteen metal ions extracted with ionic liquids containing cations 1-octyl-4-methylpyridinium [4MOPYR]{sup +}, 1-methyl-1-octylpyrrolidinium [MOPYRRO]{sup +} or 1-methyl-1-octylpiperidinium [MOPIP]{sup +}, and anions tetrafluoroborate [BF{sub 4}]{sup +}, trifluoromethyl sulfonate [TfO]{sup +} or nonafluorobutyl sulfonate [NfO]{sup +}. Ionic … more
Date: June 25, 2007
Creator: Papaiconomou, Nicolas; Lee, Jong-Min; Salminen, Justin; VonStosch, Moritz & Prausnitz, John M.
Partner: UNT Libraries Government Documents Department
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A Cell-Centered Adaptive Projection Method for the IncompressibleNavier-Stokes Equations in Three Dimensions

Description: We present a method for computing incompressible viscousflows in three dimensions using block-structured local refinement in bothspace and time. This method uses a projection formulation based on acell-centered approximate projection, combined with the systematic use ofmultilevel elliptic solvers to compute increments in the solutiongenerated at boundaries between refinement levels due to refinement intime. We use an L_0-stable second-order semi-implicit scheme to evaluatethe viscous terms. Res… more
Date: September 25, 2007
Creator: Martin, D.F.; Colella, P. & Graves, D.T.
Partner: UNT Libraries Government Documents Department
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Design and Performance of the Matching Beamline Between the Bnl Ebis and an Rfq.

Description: A part of a new EBIS-based heavy ion preinjector, the low energy beam transport (LEBT) section between the high current EBIS and the RFQ is a challenging design, because it must serve many functions. In addition to the requirement to provide an efficient matching between the EBIS and the RFQ, this line must serve as a fast ''switchyard'', allowing singly charged ions from external sources to be transported into the EBIS trap region, and extracted, highly charged ions to be deflected to off-axis… more
Date: June 25, 2007
Creator: Alessi, J.; Beebe, E.; Brodowski, J.; Kponou, A.; Okamura, M.; Pikin, A. et al.
Partner: UNT Libraries Government Documents Department
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Heavy ion fusion science research for high energy density physics and fusion applications

Description: During the past two years, the U.S. heavy ion fusion science program has made significant experimental and theoretical progress in simultaneous transverse and longitudinal beam compression, ion-beam-driven warm dense matter targets, high brightness beam transport, advanced theory and numerical simulations, and heavy ion target designs for fusion. First experiments combining radial and longitudinal compression of intense ion beams propagating through background plasma resulted in on-axis beam de… more
Date: June 25, 2007
Creator: Logan, B. G.; Bieniosek, F. M.; Barnard, J. J.; Cohen, R. H.; Coleman, J. E.; Davidson, R. C. et al.
Partner: UNT Libraries Government Documents Department
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Vibration Measurements to Study the Effect of Cryogen Flow in Superconducting Quadrupole.

Description: The conceptual design of compact superconducting magnets for the International Linear Collider final focus is presently under development. A primary concern in using superconducting quadrupoles is the potential for inducing additional vibrations from cryogenic operation. We have employed a Laser Doppler Vibrometer system to measure the vibrations in a spare RHIC quadrupole magnet under cryogenic conditions. Some preliminary results of these studies were limited in resolution due to a rather lar… more
Date: June 25, 2007
Creator: He, P.; Anerella, M.; Aydin, S.; Ganetis, G.; Harrison, M.; Jain, A. et al.
Partner: UNT Libraries Government Documents Department
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The Use of Small Coolers in a Magnetic Field

Description: Small 4 K coolers are used to cool superconducting magnets.These coolers are usually used with high temperature suerconductor (HTS)leads. In most cases, magnet is shielded with iron or active shieldcoils. Thus the field at the cooler is low. There are instances when thecooler must be in a magnetic field. Gifford McMahon (GM) coolers or pulsetube coolers are commercially available to cool the magnets. This paperwill discuss how the two types of coolers are affected by the straymagnetic field. St… more
Date: July 25, 2007
Creator: Green, Michael A. & Witte, Holger
Partner: UNT Libraries Government Documents Department
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Isotopic mass-dependence of noble gas diffusion coefficients inwater

Description: Noble gas isotopes are used extensively as tracers inhydrologic and paleoclimatic studies. These applications requireknowledge of the isotopic mass (m) dependence of noble gas diffusioncoefficients in water (D), which has not been measured but is estimatedusing experimental D-values for the major isotopes along with an untestedrelationship from kinetic theory, D prop m-0.5. We applied moleculardynamics methods to determine the mass dependence of D for four noblegases at 298 K, finding that D pr… more
Date: June 25, 2007
Creator: Bourg, I.C. & Sposito, G.
Partner: UNT Libraries Government Documents Department
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End-to-End Simulations for the Ebis Preinjector.

Description: The EBIS Project at Brookhaven National Laboratory is in the second year of a four-year project. It will replace the Tandem Van de Graaff accelerators with an Electron Beam Ion Source, an RFQ, and one IH Linac cavity, as the heavy ion preinjector for the Relativistic Heavy Ion Collider (RHIC), and for the NASA Space Radiation Laboratory (NSRL). The preinjector will provide all ions species, He to U, (Q/m >0.16) at 2 MeV/amu at a repetition rate of 5 Hz, pulse length of 10-40 {micro}s, and in… more
Date: June 25, 2007
Creator: Raparia, D.; Alessi, J.; Kponou, A.; Pikin, A.; Ritter, J.; Minaev, S. et al.
Partner: UNT Libraries Government Documents Department
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Optical Faraday Cup for Heavy Ion Beams

Description: We have been using alumina scintillators for imaging beams in heavy-ion beam fusion experiments in 2 to 4 transverse dimensions [1]. The scintillator has a limited lifetime under bombardment by the heavy ion beams. As a possible replacement for the scintillator, we are studying the technique of imaging the beam on a gas cloud. A gas cloud for imaging the beam may be created on a solid hole plate placed in the path of the beam, or by a localized gas jet. It is possible to image the beam using ce… more
Date: June 25, 2007
Creator: Bieniosek, Frank; Bieniosek, F. M.; Eylon, S.; Roy, P. K. & Yu, S. S.
Partner: UNT Libraries Government Documents Department
open access

Plasma Lens for Us Based Super Neutrino Beam at Either Fnal or Bnl.

Description: The plasma lens concept is examined as an alternative to focusing horns and solenoids for a neutrino beam facility. The concept is based on a combined high-current lens/target configuration. Current is fed at an electrode located downstream from the beginning of the target where pion capturing is needed. The current is carried by plasma outside the target. A second plasma lens section, with an additional current feed, follows the target. The plasma is immersed in a relatively small solenoidal m… more
Date: June 25, 2007
Creator: Hershcovitch, A.; Weng, W.; Diwan, M.; Gallardo, J.; Kirk, H.; Johnson, B. et al.
Partner: UNT Libraries Government Documents Department
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Numerical Study of Coulomb Scattering Effects on Electron Beamfrom a Nano-Tip

Description: Nano-tips with high acceleration gradient around the emission surface have been proposed to generate high brightness beams. However, due to the small size of the tip, the charge density near the tip is very high even for a small number of electrons. The stochastic Coulomb scattering near the tip can degrade the beam quality and cause extra emittance growth and energy spread. In the paper, we present a numerical study of these effects using a direct relativistic N-body model. We found that emitt… more
Date: June 25, 2007
Creator: Qiang, Ji; Corlett, John N.; Lidia, Steven M.; Padmore, HowardA.; Wan, Weishi; Zholent, Andrew A. et al.
Partner: UNT Libraries Government Documents Department
open access

Performance of capillary discharge guided laser plasma wakefieldaccelerator

Description: A GeV-class laser-driven plasma-based wakefield acceleratorhas been realized at the Lawrence Berkeley National Laboratory (LBNL).The device consists of the 40TW high repetition rate Ti:sapphire LOASISlaser system at LBNL and a gas-filled capillary discharge waveguidedeveloped at Oxford University. The operation of the capillary dischargeguided laser plasma wakefield accelerator with a capillaryof 225 mu mdiameter and 33 mm in length was analyzed in detail. The input intensitydependence suggests… more
Date: June 25, 2007
Creator: Nakamura, Kei; Esarey, Eric; Geddes, Cameron G. R.; Gonsalves, Anthony J.; Leemans, Wim P.; Panasenko, Dmitriy et al.
Partner: UNT Libraries Government Documents Department
open access

Physicochemical properties and toxicities of hydrophobicpiperidinium and pyrrolidinium ionic liquids

Description: Some properties are reported for hydrophobic ionic liquids (IL) containing 1-methyl-1-propyl pyrrolidinium [MPPyrro]{sup +}, 1-methyl-1-butyl pyrrolidinium [MBPyrro]{sup +}, 1-methyl-1-propyl piperidinium [MPPip]{sup +}, 1-methyl-1-butyl piperidinium [MBPip]{sup +}, 1-methyl-1-octylpyrrolidinium [MOPyrro]{sup +} and 1-methyl-1-octylpiperidinium [MOPip]{sup +} cations. These liquids provide new alternatives to pyridinium and imidazolium ILs. High thermal stability of an ionic liquid increases sa… more
Date: June 25, 2007
Creator: Salminen, Justin; Papaiconomou, Nicolas; Kumar, R. Anand; Lee,Jong-Min; Kerr, John; Newman, John et al.
Partner: UNT Libraries Government Documents Department
open access

TOWARDS 100% POLARIZATION IN THE OPTICALLY-PUMPED POLARIZED ION SOURCE.

Description: The depolarization factors in the multi-step spin-transfer polarization technique and basic limitations on maximum polarization in the OPPIS (Optically-Pumped Polarized H{sup -} Ion Source) are discussed. Detailed studies of polarization losses in the RHIC OPPIS and the source parameters optimization resulted in the OPPIS polarization increase to 86-90%. This contributed to increasing polarization in the AGS and RHIC to 65-70%.
Date: June 25, 2007
Creator: ZELENSKI,A.; ALESSI, J.; KOKHANOVSKI, S.; KPONOU, A.; RITTER, B.J. & ZUBETS, V.
Partner: UNT Libraries Government Documents Department
open access

A Detailed Chemical Kinetic Reaction Mechanism for n-Alkane Hydrocarbons from n-Octane to n-Hexadecane

Description: Detailed chemical kinetic reaction mechanisms have been developed to describe the pyrolysis and oxidation of the n-alkanes, including n-octane (n-C{sub 8}H{sub 18}), n-nonane (n-C{sub 9}H{sub 20}), n-decane (n-C{sub 10}H{sub 22}), n-undecane (n-C{sub 11}H{sub 24}), n-dodecane (n-C{sub 12}H{sub 26}), n-tridecane (n-C{sub 13}H{sub 28}), n-tetradecane (n-C{sub 14}H{sub 30}), n-pentadecane (n-C{sub 15}H{sub 32}), and n-hexadecane (n-C{sub 16}H{sub 34}). These mechanisms include both high temperatur… more
Date: September 25, 2007
Creator: Westbrook, C K; Pitz, W J; Herbinet, O; Silke, E J & Curran, H J
Partner: UNT Libraries Government Documents Department
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Thermal Emittance Measurement Design for Diamond Secondary Emission

Description: Thermal emittance is a very important characteristic of cathodes. A carefully designed method of measuring the thermal emittance of secondary emission from diamond is presented. Comparison of possible schemes is carried out by simulation, and the most accessible and accurate method and values are chosen. Systematic errors can be controlled and maintained at small values, and are carefully evaluated. Aberration and limitations of all equipment are taken into account.
Date: June 25, 2007
Creator: Wu, Q.; Ben-Zvi, Ilan; Burrill, A.; Chang, X.; Kayran, D.; Rao, T. et al.
Partner: UNT Libraries Government Documents Department
open access

SUPERCONDUCTING MAGNET NEEDS FOR THE ILC.

Description: The ILC Reference Design Report was completed early in February 2007. The Magnet Systems Group was formed to translate magnetic field requirements into magnet designs and cost estimates for the Reference Design. As presently configured, the lLC will have more than 13,000 magnetic elements of which more than 2300 will be based on superconducting technology. This paper will describe the major superconducting magnet needs for the ILC as presently determined by the Area Systems Groups, responsible … more
Date: June 25, 2007
Creator: PARKER, B.; TOMPKINS, J. C.; KASHIKHIN, V. I.; PALMER, M. A. & CLARKE, J. A.
Partner: UNT Libraries Government Documents Department
open access

The energy coupling efficiency of multi-wavelength laser pulses to damage initiating defects in DKDP nonlinear crystals

Description: The bulk damage performance of potassium dihydrogen phosphate crystals under simultaneous exposure to 1064-, 532-, and 355-nm nanosecond-laser pulses is investigated in order to probe the laser-induced defect reactions leading to damage initiation during frequency conversion. The results provide insight into the mechanisms governing the behavior of the damage initiating defects under exposure to high power laser light. In addition, it is suggested that the damage performance can be directly rel… more
Date: September 25, 2007
Creator: DeMange, P; Negres, R A; Rubenchik, A M; Radousky, H B; Feit, M D & Demos, S G
Partner: UNT Libraries Government Documents Department
open access

Colliding pulse injection experiments in non-collinear geometryfor controlled laser plasma wakefield acceleration of electrons

Description: An optical injection scheme for a laser-plasma basedaccelerator which employs a non-collinear counter-propagating laser beamto push background electrons in the focusing and acceleration phase viaponderomotive beat with the trailing part of the wakefield driver pulseis discussed. Preliminary experiments were performed using a drive beamof a_0 = 2.6 and colliding beam of a_1 = 0.8 both focused on the middleof a 200 mu m slit jet backed with 20 bar, which provided ~; 260 mu mlong gas plume. The en… more
Date: June 25, 2007
Creator: Toth, Carl B.; Esarey, Eric H.; Geddes, Cameron G.R.; Leemans,Wim P.; Nakamura, Kei; Panasenko, Dmitriy et al.
Partner: UNT Libraries Government Documents Department
open access

THE SUPERCONDUCTION MAGNETS OF THE ILC BEAM DELIVERY SYSTEM.

Description: The ILC Reference Design Report was completed early in February 2007. The Magnet Systems Group was formed to translate magnetic field requirements into magnet designs and cost estimates for the Reference Design. As presently configured, the ILC will have more than 13,000 magnetic elements of which more than 2300 will be based on superconducting technology. This paper will describe the major superconducting magnet needs for the ILC as presently determined by the Area Systems Groups, responsible … more
Date: June 25, 2007
Creator: PARKER,B.; ANEREELA, M.; ESCALLIE, J.; HE, P.; JAIN, A.; MARONE, A. et al.
Partner: UNT Libraries Government Documents Department
open access

A simple and realistic model of supersymmetry breaking

Description: We present a simple and realistic model of supersymmetry breaking. In addition to the minimal supersymmetric standard model, we only introduce a hidden sector gauge group SU(5) and three fields X, F and \bar{F}. Supersymmetry is broken at a local minimum of the potential, and its effects are transmitted to the supersymmetric standard model sector through both standard model gauge loops and local operators suppressed by the cutoff scale, which is taken to be the unification scale. The form of th… more
Date: September 25, 2007
Creator: Nomura, Yasunori & Papucci, Michele
Partner: UNT Libraries Government Documents Department
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Insertion Devices R and Ds for NSLS-II

Description: NSLS-II is a medium energy storage ring of 3GeV electron beam energy with sub-nm.rad horizontal emittance and top-off capability at 500mA. Damping wigglers will be used not only to reduce the beam emittance but also for broadband sources for users. Cryo-Permanent Magnet Undulators (CPMUs) are considered for hard X-ray linear device, and permanent magnet based Elliptically Polarized Undulators (EPUs) are for polarization control. Rigorous R&D plans have been established to pursue the perform… more
Date: June 25, 2007
Creator: Tanabe, T.; Harder, D. A.; Rakowsky, G.; Shaftan, T. & Skaritka, J.
Partner: UNT Libraries Government Documents Department
open access

Ab initio Molecular Dynamics Simulations of Water Under Static and Shock Compressed Conditions

Description: We report herein a series of ab initio simulations of water under both static and shocked conditions. We have calculated the coherent x-ray scattering intensity of several phases of water under high pressure, using ab initio Density Functional Theory (DFT). We provide new atomic scattering form factors for water at extreme conditions, which take into account frequently neglected changes in ionic charge and electron delocalization. We have also simulated liquid water undergoing shock loading of … more
Date: July 25, 2007
Creator: Goldman, N; Fried, L E; Mundy, C J; Kuo, I W; Curioni, A & Reed, E
Partner: UNT Libraries Government Documents Department
open access

Error Estimates Derived from the Data for Least-Squares Spline Fitting

Description: The use of least-squares fitting by cubic splines for the purpose of noise reduction in measured data is studied. Splines with variable mesh size are considered. The error, the difference between the input signal and its estimate, is divided into two sources: the R-error, which depends only on the noise and increases with decreasing mesh size, and the Ferror, which depends only on the signal and decreases with decreasing mesh size. The estimation of both errors as a function of time is demonstr… more
Date: June 25, 2007
Creator: Blair, Jerome
Partner: UNT Libraries Government Documents Department
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