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Electronic and Transport Properties of Artificial Gold Chains (open access)

Electronic and Transport Properties of Artificial Gold Chains

Article on electronic and transport properties of artificial gold chains.
Date: August 27, 2004
Creator: Calzolari, Arrigo; Cavazzoni, Carlo & Buongiorno Nardelli, Marco
System: The UNT Digital Library
Memory Effects in Fractional Brownian Motion with Hurst Exponent H<1/3 (open access)

Memory Effects in Fractional Brownian Motion with Hurst Exponent H<1/3

This article discusses a study on the regression to the origin of a walker driven by dynamically generated fractional Brownian motion.
Date: August 27, 2010
Creator: Bologna, Mauro; Vanni, Fabio; Krokhin, Arkadii A. & Grigolini, Paolo
System: The UNT Digital Library
Hyperon Polarization in Unpolarized Scattering Processes (open access)

Hyperon Polarization in Unpolarized Scattering Processes

Transverse polarization in the Hyperon (\Lambda) production in the unpolarizeddeep inelastic scattering and pp collisions is studied in the twist-three approach, considering the contribution from the quark-gluon-antiquark correlation distribution in nucleon. We further compare our results for deep inelastic scattering to a transverse momentum dependent factorization approach, and find consistency between the two approaches in the intermediate transverse momentum region. We also find that in pp collisions, there are only derivative terms contributions, and the non-derivative terms vanish.
Date: August 27, 2008
Creator: Zhou, Jian; Yuan, Feng & Liang, Zuo-Tang
System: The UNT Digital Library
Studies of Background Levels for the NIF Yield Diagnostics from Neutron and Gamma Radiation (open access)

Studies of Background Levels for the NIF Yield Diagnostics from Neutron and Gamma Radiation

The National Ignition Facility (NIF) at Lawrence Livermore National Laboratory (LLNL) is nearing completion of construction and is preparing for the National Ignition Campaign (NIC) with potentially significant yield in 2010. The design of a wide range of yield diagnostics in and outside the target-bay of the NIF must consider scattered background neutrons and neutron-induced gamma rays to measure neutrons and x-rays from target. The large and complex target chamber and facility make the calculation of scattered neutrons and gamma rays extremely challenging. The NIF was designed with shielded locations for many of the yield diagnostics including the neutron alcove and four diagnostic mezzanines. Accurate calculation of the background levels in these shielded locations requires advanced Monte Carlo techniques, e.g., variance reduction. Placement, size, and materials of collimators on the line of sight (LOS) through the shielding must be evaluated to trade off signal levels and unwanted backgrounds. The background at these locations is also affected by neutrons that pass through the laser beam tubes and scatter off of structures and walls in the switch yards. Detailed 3D Monte Carlo analyses are performed to determine neutron and gamma fluxes for some of the yield diagnostics.
Date: August 27, 2007
Creator: Song, P.; Eder, D.; Moran, M.; Landen, O.; O'Brien, D. & Hsing, W.
System: The UNT Digital Library
GLASS FORMULATION DEVELOPMENT AND TESTING FOR COLD CRUCIBLE INDUCTION MELTER (CCIM) ADVANCED REMEDIATION TECHNOLOGIES DEMONSTRATION PROJECT - 9208 (open access)

GLASS FORMULATION DEVELOPMENT AND TESTING FOR COLD CRUCIBLE INDUCTION MELTER (CCIM) ADVANCED REMEDIATION TECHNOLOGIES DEMONSTRATION PROJECT - 9208

Over the past few years, Cold Crucible Induction Melter (CCIM) demonstrations have been completed using SRS sludge batches 2, 3 and 4 (SB2, SB3 and SB4) simulant compositions. These campaigns demonstrated the ability of the CCIM to effectively produce quality glasses at high waste loadings. The current Advanced Remediation Technology (ART) Phase II-A Project is aimed at demonstrating the CCIM technology under representative DWPF flowsheet conditions and to demonstrate extended operations of the melter. A glass composition development effort was completed to identify and recommend a frit composition and sludge batch 4 (SB4) simulant waste loading target for subsequent ART-Phase II-A CCIM demonstration testing. Based on the results of the glass formulation testing, it was recommended that the Frit 503-R6 composition (B{sub 2}O{sub 3} = 14 wt %; Li{sub 2}O = 9 wt %; Na{sub 2}O = 3 wt %; and SiO{sub 2} = 74 wt %) be utilized for the demonstration. Furthermore, a waste loading of 46 wt % was recommended. The recommended frit and waste loading would produce a glass with acceptable durability with a liquidus temperature adequately below the 1250 C nominal CCIM operating temperature. This frit composition and waste loading was found to result in a …
Date: August 27, 2008
Creator: Marra, J; Amanda Billings, A; David Peeler, D; Michael Stone, M & Tommy Edwards, T
System: The UNT Digital Library
The Effect of Magnetic Field on the Position of HTS Leads and theCooler in the Services Tower of the MICE Focusing Magnet (open access)

The Effect of Magnetic Field on the Position of HTS Leads and theCooler in the Services Tower of the MICE Focusing Magnet

The MICE focusing solenoids have three 4 K coolers (two forthe superconducting magnet and one for the liquid absorber) and four HTSleads that feed the current to the focusing coils. The focusing solenoidsproduce large radial external fields when they operate with the polarityof the two coils in opposition (the gradient or flip mode). When the MICEfocusing coils operate at the same polarity (the solenoid or non-flipmode), the fields are much smaller and parallel to the axis of thesolenoid. The worst-case magnetic field affects the selection of thecooler and the HTS leads. This magnetic field can also determine theheight of the service towers that house the three coolers and the fourHTS leads. This paper shows the criteria used for Cooler selection, HTSlead selection, and the position of both the cooler and leads withrespect to the solenoid axis of rotation.
Date: August 27, 2007
Creator: Green, M. A.; Yang, S. Q.; Cobb, J.; Lau, P.; Lau, W. W.; Witte, H. et al.
System: The UNT Digital Library
THE DOE OFFICE OF ENVIRONMENTAL MANAGEMENT INTERNATIONAL COOPERATIVE PROGRAM: CURRENT STATUS AND PLANS FOR EXPANSION (open access)

THE DOE OFFICE OF ENVIRONMENTAL MANAGEMENT INTERNATIONAL COOPERATIVE PROGRAM: CURRENT STATUS AND PLANS FOR EXPANSION

None
Date: August 27, 2008
Creator: Marra, J; Kevin Fox, K; David Peeler, D; Michael02 Smith, M; Tim Jannik, T & Eduardo Farfan, E
System: The UNT Digital Library
The Engineering Design of the 1.5 m Diameter Solenoid for the MICERFCC Modules (open access)

The Engineering Design of the 1.5 m Diameter Solenoid for the MICERFCC Modules

The RF coupling coil (RFCC) module of MICE is where muonsthat have been cooled within the MICE absorber focus (AFC) modules arere-accelerated to their original longitudinal momentum. The RFCC moduleconsists of four 201.25 MHz RF cavities in a 1.4 meter diameter vacuumvessel. The muons are kept within the RF cavities by the magnetic fieldgenerated by a superconducting coupling solenoid that goes around the RFcavities. The coupling solenoid will be cooled using a pair of 4 K pulsetube cooler that will generate 1.5 W of cooling at 4.2 K. The magnet willbe powered using a 300 A two-quadrant power supply. This report describesthe ICST engineering design of the coupling solenoid forMICE.
Date: August 27, 2007
Creator: Wang, L.; Green, M. A.; Xu, F. Y.; Wu, H.; Li, L. K.; Gou, C. S. et al.
System: The UNT Digital Library
The Cost of Superconducting Magnets as a Function of Stored Energy and Design Magnetic Induction Times the Field Volume (open access)

The Cost of Superconducting Magnets as a Function of Stored Energy and Design Magnetic Induction Times the Field Volume

By various theorems one can relate the capital cost of superconducting magnets to the magnetic energy stored within that magnet. This is particularly true for magnet where the cost is dominated by the structure needed to carry the magnetic forces. One can also relate the cost of the magnet to the product of the magnetic induction and the field volume. The relationship used to estimate the cost the magnet is a function of the type of magnet it is. This paper updates the cost functions given in two papers that were published in the early 1990 s. The costs (escalated to 2007 dollars) of large numbers of LTS magnets are plotted against stored energy and magnetic field time field volume. Escalated costs for magnets built since the early 1990 s are added to the plots.
Date: August 27, 2007
Creator: Green, Mike; Green, M. A. & Strauss, B. P.
System: The UNT Digital Library
MECHANISMS OF PHASE FORMATION IN THE VITRIFICATION OF HIGH-FERROUS SAVANNAH RIVER SITE SB2 HLW SLUDGE SURROGATE - 9300 (open access)

MECHANISMS OF PHASE FORMATION IN THE VITRIFICATION OF HIGH-FERROUS SAVANNAH RIVER SITE SB2 HLW SLUDGE SURROGATE - 9300

Phase formation mechanisms associated with the vitrification of high-ferrous Savannah River Site (SRS) Sludge Batch 2 (SB2) high level waste surrogate were studied by infrared spectroscopy (IRS) and X-ray diffraction (XRD). Two mixtures at 50 wt% waste loading with commercially available Frit 320 (Li{sub 2}O - 8 wt %, B{sub 2}O{sub 3} - 8 wt %, Na{sub 2}O - 12 wt %, SiO{sub 2} - 72 wt %) and batch chemicals (LiOH {center_dot} H{sub 2}O, H{sub 3}BO{sub 3}, NaNO{sub 3}, SiO{sub 2}) to represent the frit formulation were prepared as slurries with a water content of {approx}50 wt%. The mixtures were air-dried at a temperature of 115 C and heat-treated at 500, 700, 900, 1000, 1100, 1200, and 1300 C for 1 hr at each temperature. Infrared spectra and XRD patterns of the products produced at each temperature were recorded. In both mixtures prepared using frit and batch chemicals to represent the frit, phase formation reactions were completed within the temperature range between 900 and 1000 C. However, residual quartz was still present in glass produced from the mixture with batch chemicals even at 1100 C. Although, the phase composition and structure of the glassy products obtained from both mixtures …
Date: August 27, 2008
Creator: Marra, J
System: The UNT Digital Library
Assembly and Test of a Support Structure for 3.5 m Long Nb3Sn Racetrack Coils. (open access)

Assembly and Test of a Support Structure for 3.5 m Long Nb3Sn Racetrack Coils.

The LHC Accelerator Research Program (LARP) is currently developing 4 m long Nb{sub 3}Sn quadrupole magnets for a possible upgrade of the LHC Interaction Regions (IR). In order to provide a reliable test bed for the fabrication and test of long Nb{sub 3}Sn coils, LARP has started the development of the long racetrack magnet LRS01. The magnet is composed of two 3.6 m long racetrack coils contained in a support structure based on an aluminum shell pre-tensioned with water-pressurized bladders and interference keys. For the phase-one test of the assembly procedure and loading operation, the structure was pre-stressed at room temperature and cooled down to 77 K with instrumented, solid aluminum 'dummy coils'. Mechanical behavior and stress homogeneity were monitored with strain gauges mounted on the shell and the dummy coils. The dummy coils were replaced with reacted and impregnated Nb{sub 3}Sn coils in a second assembly procedure, followed by cool-down to 4.5 K and powered magnet test. This paper reports on the assembly and loading procedures of the support structure as well as the comparison between strain gauge data and 3D model predictions.
Date: August 27, 2007
Creator: Ferracin, P.; Ambrosio, G.; Anerella, M.; Caspi, S.; Cheng, D. W.; Felice, H. et al.
System: The UNT Digital Library
LARP Long Nb3Sn Quadrupole Design. (open access)

LARP Long Nb3Sn Quadrupole Design.

A major milestone for the LHC Accelerator Research Program (LARP) is the test, by the end of 2009, of two 4m-long quadrupole magnets (LQ) wound with Nb{sub 3}Sn conductor. The goal of these magnets is to be a proof of principle that Nb{sub 3}Sn is a viable technology for a possible LHC luminosity upgrade. The design of the LQ is based on the design of the LARP Technological Quadrupoles, presently under development at FNAL and LBNL, with 90-mm aperture and gradient higher than 200 T/m. The design of the first LQ model will be completed by the end of 2007 with the selection of a mechanical design. In this paper we present the coil design addressing some fabrication technology issues, the quench protection study, and three designs of the support structure.
Date: August 27, 2007
Creator: Ambrosio, G.; Andreev, N.; Anerella, M.; Barzi, E.; Bossert, R.; Caspi, S. et al.
System: The UNT Digital Library
The Helium Cooling System and Cold Mass Support System for theMICE Coupling Solenoid (open access)

The Helium Cooling System and Cold Mass Support System for theMICE Coupling Solenoid

The MICE cooling channel consists of alternating threeabsorber focus coil module (AFC) and two RF coupling coil module (RFCC)where the process of muon cooling and reacceleration occurs. The RFCCmodule comprises a superconducting coupling solenoid mounted around fourconventional conducting 201.25 MHz closed RF cavities and producing up to2.2T magnetic field on the centerline. The coupling coil magnetic fieldis to produce a low muon beam beta function in order to keep the beamwithin the RF cavities. The magnet is to be built using commercialniobium titanium MRI conductors and cooled by pulse tube coolers thatproduce 1.5 W of cooling capacity at 4.2 K each. A self-centering supportsystem is applied for the coupling magnet cold mass support, which isdesigned to carry a longitudinal force up to 500 kN. This report willdescribe the updated design for the MICE coupling magnet. The cold masssupport system and helium cooling system are discussed indetail.
Date: August 27, 2007
Creator: Wang, L.; Wu, H.; Li, L. K.; Green, M. A.; Liu, C. S.; Li, L. Y. et al.
System: The UNT Digital Library
MICE Spectrometer Magnet System Progress (open access)

MICE Spectrometer Magnet System Progress

The first magnets for the muon ionization cooling experimentwill be the tracker solenoids that form the ends of the MICE coolingchannel. The primary purpose of the tracker solenoids is to provide auniform 4 T field (to better than +-0.3 percent over a volume that is 1meter long and 0.3 meters in diameter) spectrometer magnet field for thescintillating fiber detectors that are used to analyze the muons in thechannel before and after ionization cooling. A secondary purpose for thetracker magnet is the matching of the muon beam between the rest of theMICE cooling channel and the uniform field spectrometer magnet. Thetracker solenoid is powered by three 300 amp power supplies. Additionaltuning of the spectrometer is provided by a pair of 50 amp power suppliesacross the spectrometer magnet end coils. The tracker magnet will becooled using a pair of 4 K pulse tube coolers that each provide 1.5 W ofcooling at 4.2 K. Final design and construction of the tracker solenoidsbegan during the summer of 2006. This report describes the progress madeon the construction of the tracker solenoids.
Date: August 27, 2007
Creator: Green, Michael A. & Virostek, Steve P.
System: The UNT Digital Library
Transport and Magnetization Properties of rolled RRP Nb3Sn Strands. (open access)

Transport and Magnetization Properties of rolled RRP Nb3Sn Strands.

Restack Rod Process (RRP) strands with 54 and 108 sub-elements were rolled from 0.7 mm diameter to 0.45 mm thickness to simulate the deformation of strands at the edges of Rutherford cables. Various diagnoses were then applied to assess performance and stability. Transport measurements were used to assess the effect of rolling on the critical current. Magnetization measurements were used to probe superconducting pathway bridging between deformed sub-elements. The copper residual resistivity ratio RRR was also measured to assess tin contamination due to thinned or ruptured diffusion barriers. While systematic changes were observed in all three measurements with increasing deformation, RRR showed the strongest changes. The implications of these measurements for cable stability, and their relationship to observations of the strand cross-section by light microscopy, are discussed.
Date: August 27, 2007
Creator: Ghosh, A. K.; Cooley, L. D.; Dietderich, D. R. & Sun, L.
System: The UNT Digital Library
The Cost of Helium Refrigerators and Coolers for SuperconductingDevices as a Function of Cooling at 4 K (open access)

The Cost of Helium Refrigerators and Coolers for SuperconductingDevices as a Function of Cooling at 4 K

This paper is an update of papers written in 1991 and in1997 by Rod Byrns and this author concerning estimating the cost ofrefrigeration for superconducting magnets and cavities. The actual costsof helium refrigerators and coolers (escalated to 2007 dollars) areplotted and compared to a correlation function. A correlation functionbetween cost and refrigeration at 4.5 K is given. The capital cost oflarger refrigerators (greater than 10 W at 4.5 K) is plotted as afunction of 4.5-K cooling. The cost of small coolers is plotted as afunction of refrigeration available at 4.2 K. A correlation function forestimating efficiency (percent of Carnot) of both types of refrigeratorsis also given.
Date: August 27, 2007
Creator: Green, Michael A.
System: The UNT Digital Library
Inverted Social Reward: Associations between Psychopathic Traits and Self-Report and Experimental Measures of Social Reward (open access)

Inverted Social Reward: Associations between Psychopathic Traits and Self-Report and Experimental Measures of Social Reward

This article describes two studies of individuals with high levels of psychopathic traits. Study 1 explores what aspects of social reward are associated with psychopathic traits, and Study 2 administers these measures to a new group of participants along with two experimental tasks investigating monetary and social reward value.
Date: August 27, 2014
Creator: Foulkes, Lucy; McCrory, Eamon J.; Neumann, Craig S. & Viding, Essi
System: The UNT Digital Library
Analytic ICF Hohlraum Energetics (open access)

Analytic ICF Hohlraum Energetics

We apply recent analytic solutions to the radiation diffusion equation to problems of interest for ICF hohlraums. The solutions provide quantitative values for absorbed energy which are of use for generating a desired radiation temperature vs. time within the hohlraum. Comparison of supersonic and subsonic solutions (heat front velocity faster or slower, respectively, than the speed of sound in the x-ray heated material) suggests that there may be some advantage in using high Z metallic foams as hohlraum wall material to reduce hydrodynamic losses, and hence, net absorbed energy by the walls. Analytic and numerical calculations suggest that the loss per unit area might be reduced {approx} 20% through use of foam hohlraum walls. Reduced hydrodynamic motion of the wall material may also reduce symmetry swings, as found for heavy ion targets.
Date: August 27, 2003
Creator: Rosen, M D & Hammer, J
System: The UNT Digital Library
The ANL experiment for a wake field accelerator using an rf structure (open access)

The ANL experiment for a wake field accelerator using an rf structure

Experiments are planned at ANL to study a new accelerating concept that has been developed during the last few years named the WAKEATRON. This requires a very special, simple configuration of the beams and of the rf structure involved. The basic concepts are explained. Like most proposed experimental work, this too was initiated by a considerable amount of computational work, both analytical and numerical, on which we would like to report. We will then describe details of the planned experiments we will carry out at ANL to check some of our predictions for this concept. These experiments concentrate on beam and cavity geometry applicable to the Wakeatron.
Date: August 27, 1986
Creator: Ruggiero, A. G.; Schoessow, P. & Simpson, J.
System: The UNT Digital Library
Hydrodynamic Issues in PAMS Mandrel Target Fabrication (open access)

Hydrodynamic Issues in PAMS Mandrel Target Fabrication

Imperfections in PAMS mandrels critically govern the quality of final ICF targets. Imperfections in the mandrels can have a wide range of origins. Here, they present observations of 3 types of imperfections, and data to support the proposal that hydrodynamic factors during the curing of the mandrel are potential causes of these imperfections.
Date: August 27, 2003
Creator: McQuillan, B M; Paguio, R; Subramanian, P; Takagi, M & Zebib, A
System: The UNT Digital Library
PRESERVATION OF H2 PRODUCTION ACTIVITY IN NANOPOROUS LATEX COATINGS OF RHODOPSEUDOMONAS PALUSTRIS CGA009 DURING DRY STORAGE AT AMBIENT TEMPERATURES (open access)

PRESERVATION OF H2 PRODUCTION ACTIVITY IN NANOPOROUS LATEX COATINGS OF RHODOPSEUDOMONAS PALUSTRIS CGA009 DURING DRY STORAGE AT AMBIENT TEMPERATURES

To assess the applicability of latex cell coatings as an &quot;off-the-shelf&#x27; biocatalyst, the effect of osmoprotectants, temperature, humidity and O{sub 2} on preservation of H{sub 2} production in Rhodopseudomonas palustris coatings was evaluated. Immediately following latex coating coalescence (24 h) and for up to 2 weeks of dry storage, rehydrated coatings containing different osmoprotectants displayed similar rates of H{sub 2} production. Beyond 2 weeks of storage, sorbitol- treated coatings lost all H{sub 2} production activity, whereas considerable H{sub 2} production was still detected in sucrose- and trehalose-stabilized coatings. The relative humidity level at which the coatings were stored had a significant impact on the recovery and subsequent rates of H{sub 2} production. After 4 weeks storage under air at 60% humidity, coatings produced only trace amounts of H{sub 2} (0-0.1% headspace accumulation), whereas those stored at &lt;5% humidity retained 27-53% of their H{sub 2} production activity after 8 weeks of storage. When stored in argon at &lt;5% humidity and room temperature, R. palustris coatings retained full H{sub 2} production activity for 3 months, implicating oxidative damage as a key factor limiting coating storage. Overall, the results demonstrate that biocatalytic latex coatings are an attractive cell immobilization platform for preservation of …
Date: August 27, 2012
Creator: Milliken, C.; Piskorska, M.; Soule, T.; Gosse, J.; Flickinger, M.; Smith, G. et al.
System: The UNT Digital Library
Monte Carlo Simulation of Neutron Noise Effects on Beam Position Determination With Real and Simulated Beam Images at the National Ignition Facility (open access)

Monte Carlo Simulation of Neutron Noise Effects on Beam Position Determination With Real and Simulated Beam Images at the National Ignition Facility

None
Date: August 27, 2013
Creator: Awwal, A.; Leach, R.; Datte, P. & Manuel, A.
System: The UNT Digital Library
The Effects of the Scattering by Edge Plasma Density Fluctuations on Lower Hyybrid Wave Propagation (open access)

The Effects of the Scattering by Edge Plasma Density Fluctuations on Lower Hyybrid Wave Propagation

Scattering effects induced by edge density fluctuations on lower hybrid (LH) wave propagation are investigated. The scattering model used here is based on the work of Bonoli and Ott [Phys. Fluids 25 (1982) 361]. It utilizes an electromagnetic wave kinetic equation solved by a Monte Carlo technique. This scattering model has been implemented in GENRAY , a ray tracing code which explicitly simulates wave propagation, as well as collisionless and collisional damping processes, over the entire plasma discharge, including the scrape-off layer (SOL) that extends from the separatrix to the vessel wall. A numerical analysis of the LH wave trajectories and the power deposition profile with and without scattering is presented for Alcator CMod discharges. Comparisons between the measured hard x-ray emission on Alcator C-Mod and simulations of the data obtained from the synthetic diagnostic included in the GENRAY/CQL3D package are shown, with and without the combination of scattering and collisional damping. Implications of these results on LH current drive are discussed.
Date: August 27, 2012
Creator: Bertelli, N.; Bonoli, P. T.; Harvey, R. W.; Smirnov, A. P.; Baek, S. G.; Parker, R. R. et al.
System: The UNT Digital Library
Theoretical Summary Lecture for Higgs Hunting 2012 (open access)

Theoretical Summary Lecture for Higgs Hunting 2012

In this lecture, I review some of the perspectives on the Higgs boson discussed at the Higgs Hunting 2012 Worshop and discuss the short- and long-term aspects of Higgs physics.
Date: August 27, 2012
Creator: Peskin, Michael E.
System: The UNT Digital Library