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Edge Turbulence Velocity Changes with Lithium Coating on NSTX (open access)

Edge Turbulence Velocity Changes with Lithium Coating on NSTX

Lithium coating improves energy confinement and eliminates edge localized modes in NSTX, but the mechanism of this improvement is not yet well understood. We used the gas-puff-imaging (GPI) diagnostic on NSTX to measure the changes in edge turbulence which occurred during a scan with variable lithium wall coating, in order to help understand the reason for the confinement improvement with lithium. There was a small increase in the edge turbulence poloidal velocity and a decrease in the poloidal velocity fluctuation level with increased lithium. The possible effect of varying edge neutral density on turbulence damping was evaluated for these cases in NSTX. __________________________________________________
Date: August 10, 2012
Creator: A. Cao, S.J. Zweben, D.P. Stotler, M. Bell, A. Diallo, S.M. Kaye and B. LeBlanc
Object Type: Report
System: The UNT Digital Library
Potential for luminosity improvement for low-energy RHIC operation with long bunches (open access)

Potential for luminosity improvement for low-energy RHIC operation with long bunches

Electron cooling was proposed to increase luminosity of the RHIC collider for heavy ion beams at low energies. Luminosity decreases as the square of bunch intensity due to the beam loss from the RF bucket as a result of the longitudinal intra beam scattering (IBS), as well as due to the transverse emittance growth because of the transverse IBS. Both transverse and longitudinal IBS can be counteracted with electron cooling. This would allow one to keep the initial peak luminosity close to constant throughout the store essentially without the beam loss. In addition, the phase-space density of the hadron beams can be further increased by providing stronger electron cooling. Unfortunately, the defining limitation for low energies in RHIC is expected to be the space charge. Here we explore an idea of additional improvement in luminosity, on top of the one coming from just IBS compensation and longer stores, which may be expected if one can operate with longer bunches at the space-charge limit in a collider. This approach together with electron cooling may result in about 10-fold improvement in total luminosity for low-energy RHIC program.
Date: February 10, 2012
Creator: A., Fedotov; Blaskiewicz&#44 & M.
Object Type: Report
System: The UNT Digital Library
Prediction of Partition Coeffecients  and Permeability of Drug Molecules in Biological Systems with Abraham Model Solute Descriptors Derived from Measured Solubilities and Water-to-Organic Solvent Partition Coefficients (open access)

Prediction of Partition Coeffecients and Permeability of Drug Molecules in Biological Systems with Abraham Model Solute Descriptors Derived from Measured Solubilities and Water-to-Organic Solvent Partition Coefficients

Book chapter on the prediction of partition coefficients and permeability of drug molecules in biological systems with Abraham model solute descriptors derived from measured solubilities and water-to-organic solvent partition coefficients.
Date: February 10, 2012
Creator: Acree, William E. (William Eugene); Grubbs, Laura M. & Abraham, M. H. (Michael H.)
Object Type: Book Chapter
System: The UNT Digital Library
Prediction of Toxicity, Sensory Responses and Biological Responses with the Abraham Model (open access)

Prediction of Toxicity, Sensory Responses and Biological Responses with the Abraham Model

This book chapter discusses the prediction of toxicity, sensory responses and biological responses with the Abraham model.
Date: February 10, 2012
Creator: Acree, William E. (William Eugene); Grubbs, Laura M. & Abraham, M. H. (Michael H.)
Object Type: Book Chapter
System: The UNT Digital Library
LITERATURE REVIEW ON IMPACT OF GLYCOLATE ON THE 2H EVAPORATOR AND THE EFFLUENT TREATMENT FACILITY (open access)

LITERATURE REVIEW ON IMPACT OF GLYCOLATE ON THE 2H EVAPORATOR AND THE EFFLUENT TREATMENT FACILITY

Glycolic acid (GA) is being studied as an alternate reductant in the Defense Waste Processing Facility (DWPF) feed preparation process. It will either be a total or partial replacement for the formic acid that is currently used. A literature review has been conducted on the impact of glycolate on two post-DWPF downstream systems - the 2H Evaporator system and the Effluent Treatment Facility (ETF). The DWPF recycle stream serves as a portion of the feed to the 2H Evaporator. Glycolate enters the evaporator system from the glycolate in the recycle stream. The overhead (i.e., condensed phase) from the 2H Evaporator serves as a portion of the feed to the ETF. The literature search revealed that virtually no impact is anticipated for the 2H Evaporator. Glycolate may help reduce scale formation in the evaporator due to its high complexing ability. The drawback of the solubilizing ability is the potential impact on the criticality analysis of the 2H Evaporator system. It is recommended that at least a theoretical evaluation to confirm the finding that no self-propagating violent reactions with nitrate/nitrites will occur should be performed. Similarly, identification of sources of ignition relevant to glycolate and/or update of the composite flammability analysis to …
Date: May 10, 2012
Creator: Adu-Wusu, K.
Object Type: Report
System: The UNT Digital Library
Measuring Sparticles with the Matrix Element (open access)

Measuring Sparticles with the Matrix Element

We apply the Matrix Element Method (MEM) to mass determination of squark pair production with direct decay to quarks and LSP at the LHC, showing that simultaneous mass determination of squarks and LSP is possible. We furthermore propose methods for inclusion of QCD radiation effects in the MEM. The goal of the LHC at CERN, scheduled to start this year, is to discover new physics through deviations from the Standard Model (SM) predictions. After discovery of deviations from the SM, the next step will be classification of the new physics. An important first goal in this process will be establishing a mass spectrum of the new particles. One of the most challenging scenarios is pair-production of new particles which decay to invisible massive particles, giving missing energy signals. Many methods have been proposed for mass determination in such scenarios (for a recent list of references, see e.g. [1]). In this proceeding, we report the first steps in applying the Matrix Element Method (MEM) in the context of supersymmetric scenarios giving missing energy signals. After a quick review of the MEM, we will focus on squark pair production, a process where other mass determination techniques have difficulties to simultaneously determine the …
Date: April 10, 2012
Creator: Alwall, Johan; /SLAC /Taiwan, Natl. Taiwan U.; Freitas, Ayres; U., /Pittsburgh; Mattelaer, Olivier & /INFN, Rome3 /Rome III U. /Louvain U.
Object Type: Article
System: The UNT Digital Library
Stauts of the Laser Inertial Fusion Energy (LIFE) Hohlraum Point Design (open access)

Stauts of the Laser Inertial Fusion Energy (LIFE) Hohlraum Point Design

Progress on the hohlraum point design for the LIFE engine is described. New features in the original design [Amendt et al., Fus. Sci. Technol. 60, 49 (2011)] are incorporated that address the imperatives of low target cost, high manufacturing throughput, efficient and prompt material recycling, an ability for near-term testing of key target design uncertainties on the National Ignition Facility, and robustness to target chamber environment and injection insults. To this end, the novel use of Pb hohlraums and aerogel-supported liquid DT fuel loading within a high-density-carbon (HDC) ablator is implemented in the hohlraum point design.
Date: April 10, 2012
Creator: Amendt, P.; Dunne, M.; Ho, D.; Lasinski, B.; Meeker, D. & Ross, J. S.
Object Type: Article
System: The UNT Digital Library
The SM and NLO Multileg Working Group: Summary Report (open access)

The SM and NLO Multileg Working Group: Summary Report

After years of waiting, and after six Les Houches workshops, the era of LHC running is finally upon us, albeit at a lower initial center-of-mass energy than originally planned. Thus, there has been a great sense of anticipation from both the experimental and theoretical communities. The last two years, in particular, have seen great productivity in the area of multi-parton calculations at leading order (LO), next-to-leading order (NLO) and next-to-next-to-leading order (NNLO), and this productivity is reflected in the proceedings of the NLM group. Both religions, Feynmanians and Unitarians, as well as agnostic experimenters, were well-represented in both the discussions at Les Houches, and in the contributions to the write-up. Next-to-leading order (NLO) is the first order at which the normalization, and in some cases the shape, of perturbative cross sections can be considered reliable. This can be especially true when probing extreme kinematic regions, as for example with boosted Higgs searches considered in several of the contributions to this writeup. A full understanding for both standard model and beyond the standard model physics at the LHC requires the development of fast, reliable programs for the calculation of multi-parton final states at NLO. There have been many advances in the …
Date: April 10, 2012
Creator: Andersen, J. R.; Archibald, J.; Badger, S.; Ball, R. D.; Bevilacqua, G.; Bierenbaum, I. et al.
Object Type: Article
System: The UNT Digital Library
2012 Farm Bill: Changing the Treatment of LIHEAP Receipt in the Calculation of SNAP Benefits (open access)

2012 Farm Bill: Changing the Treatment of LIHEAP Receipt in the Calculation of SNAP Benefits

This report describes the contents of the 2012 Farm Bill, cost reducing measures in the Farm Bill, and the implications of both of these. Specifically, the report focuses on SNAP (Supplemental Nutrition Assistance Program) which is a cost saving measure that addresses how certain deductions from income will be calculated.
Date: July 10, 2012
Creator: Aussenberg, Randy Alison & Perl, Libby
Object Type: Report
System: The UNT Digital Library
Mechanical Design of a High Energy Beam Absorber for the Advanced Superconducting Test Accelerator (ASTA) at Fermilab (open access)

Mechanical Design of a High Energy Beam Absorber for the Advanced Superconducting Test Accelerator (ASTA) at Fermilab

A high energy beam absorber has been built for the Advanced Superconducting Test Accelerator (ASTA) at Fermilab. In the facility's initial configuration, an electron beam will be accelerated through 3 TTF-type or ILC-type SRF cryomodules to an energy of 750MeV. The electron beam will be directed to one of multiple downstream experimental and diagnostic beam lines and then deposited in one of two beam absorbers. The facility is designed to accommodate up to 6 cryomodules, which would produce a 75kW beam at 1.5GeV; this is the driving design condition for the beam absorbers. The beam absorbers consist of water-cooled graphite, aluminum and copper layers contained in a helium-filled enclosure. This paper describes the mechanical implementation of the beam absorbers, with a focus on thermal design and analysis. The potential for radiation-induced degradation of the graphite is discussed.
Date: May 10, 2012
Creator: Baffes, C.; Church, M.; Leibfritz, J.; Oplt, S. & Rakhno, I.
Object Type: Article
System: The UNT Digital Library
Mach-Zehnder Modulator Performance Using the Comet Laser Facility and Implications for Use on NIF (open access)

Mach-Zehnder Modulator Performance Using the Comet Laser Facility and Implications for Use on NIF

None
Date: July 10, 2012
Creator: Beeman, B.; MacPhee, A. G.; Kimbrough, J. R.; Lacaille, G. A.; Barrios, M. A.; Emig, J. et al.
Object Type: Article
System: The UNT Digital Library
On the Lack of Evolution in Galaxy Star Formation Efficiency (open access)

On the Lack of Evolution in Galaxy Star Formation Efficiency

None
Date: December 10, 2012
Creator: Behroozi, Peter S.; Wechsler, Risa H.; /KIPAC, Menlo Park /SLAC; Conroy, Charlie & /UC, Santa Cruz, Astron. Astrophys.
Object Type: Article
System: The UNT Digital Library
Clic Cdr - Physics and Detectors: Clic Conceptual Design Report. (open access)

Clic Cdr - Physics and Detectors: Clic Conceptual Design Report.

This report forms part of the Conceptual Design Report (CDR) of the Compact LInear Collider (CLIC). The CLIC accelerator complex is described in a separate CDR volume. A third document, to appear later, will assess strategic scenarios for building and operating CLIC in successive center-of-mass energy stages. It is anticipated that CLIC will commence with operation at a few hundred GeV, giving access to precision standard-model physics like Higgs and top-quark physics. Then, depending on the physics landscape, CLIC operation would be staged in a few steps ultimately reaching the maximum 3 TeV center-of-mass energy. Such a scenario would maximize the physics potential of CLIC providing new physics discovery potential over a wide range of energies and the ability to make precision measurements of possible new states previously discovered at the Large Hadron Collider (LHC). The main purpose of this document is to address the physics potential of a future multi-TeV e{sup +}e{sup -} collider based on CLIC technology and to describe the essential features of a detector that are required to deliver the full physics potential of this machine. The experimental conditions at CLIC are significantly more challenging than those at previous electron-positron colliders due to the much higher …
Date: February 10, 2012
Creator: Berger, E.; Demarteau, M.; Repond, J.; Xia, L. & Weerts, H.
Object Type: Report
System: The UNT Digital Library
DEVELOPMENT OF THE HS99 AIR TRANSPORT TYPE A FISSILE PACKAGE (open access)

DEVELOPMENT OF THE HS99 AIR TRANSPORT TYPE A FISSILE PACKAGE

An air-transport Type A Fissile radioactive shipping package for the transport of special form uranium sources has been developed by the Savannah River National Laboratory (SRNL) for the Department of Homeland Security. The Package model number is HS99 for Homeland Security Model 99. This paper presents the major design features of the HS99 and highlights engineered materials necessary for meeting the design requirements for this light-weight Type AF packaging. A discussion is provided demonstrating how the HS99 complies with the regulatory safety requirements of the Nuclear Regulatory Commission. The paper summarizes the results of structural testing to specified in 10 CFR 71 for Normal Conditions of Transport and Hypothetical Accident Conditions events. Planned and proposed future missions for this packaging are also addressed.
Date: July 10, 2012
Creator: Blanton, P. & Eberl, K.
Object Type: Article
System: The UNT Digital Library
Multiplexed gas spectroscopy using tunable VCSELs (open access)

Multiplexed gas spectroscopy using tunable VCSELs

Detection and identification of gas species using tunable laser diode laser absorption spectroscopy has been performed using vertical cavity surface emitting lasers (VCSEL). Two detection methods are compared: direct absorbance and wavelength modulation spectroscopy (WMS). In the first, the output of a DC-based laser is directly monitored to detect for any quench at the targeted specie wavelength. In the latter, the emission wavelength of the laser is modulated by applying a sinusoidal component on the drive current of frequency {omega}, and measuring the harmonics component (2{omega}) of the photo-detected current. This method shows a better sensitivity measured as signal to noise ratio, and is less susceptible to interference effects such as scattering or fouling. Gas detection was initially performed at room temperature and atmospheric conditions using VCSELs of emission wavelength 763 nm for oxygen and 1392 nm for water, scanning over a range of approximately 10 nm, sufficient to cover 5-10 gas specific absorption lines that enable identification and quantization of gas composition. The amplitude and frequency modulation parameters were optimized for each detected gas species, by performing two dimensional sweeps for both tuning current and either amplitude or frequency, respectively. We found that the highest detected signal is observed …
Date: April 10, 2012
Creator: Bond, T; Bond, S; McCarrick, J; Zumstein, J; Chang, A; Moran, B et al.
Object Type: Article
System: The UNT Digital Library
The role of members of viral quasispecies in adaptation to new host environments (open access)

The role of members of viral quasispecies in adaptation to new host environments

None
Date: February 10, 2012
Creator: Borucki, M.; Allen, J. E.; Chen-Harris, H.; Mabery, S.; Vanier, G.; Torres, C. et al.
Object Type: Article
System: The UNT Digital Library
On The Record, Vol. 4, No. 3, Ed. 1 Friday, August 10, 2012 (open access)

On The Record, Vol. 4, No. 3, Ed. 1 Friday, August 10, 2012

Summer magazine produced and edited by students at the University of North Texas in Denton, Texas. Articles cover local and campus news, information, and events, along with human interest stories about campus and community life.
Date: August 10, 2012
Creator: Bottoni, Paul
Object Type: Journal/Magazine/Newsletter
System: The Portal to Texas History
FY2013 Appropriations: District of Columbia (open access)

FY2013 Appropriations: District of Columbia

None
Date: August 10, 2012
Creator: Boyd, Eugene
Object Type: Report
System: The UNT Digital Library
Workforce Investment Act (WIA) Reauthorization Proposals in the 112th Congress: Comparison of Major Features of Current Law and H.R. 4297 (open access)

Workforce Investment Act (WIA) Reauthorization Proposals in the 112th Congress: Comparison of Major Features of Current Law and H.R. 4297

None
Date: August 10, 2012
Creator: Bradley, David H. & Collins, Benjamin
Object Type: Report
System: The UNT Digital Library
NEAMS Update. Quarterly Report for April - June 2012 (open access)

NEAMS Update. Quarterly Report for April - June 2012

None
Date: August 10, 2012
Creator: Bradley, K. S.; Hayes, S.; Pointer, D.; Summers, R.; Sadasivan, P.; Sun, X. et al.
Object Type: Report
System: The UNT Digital Library
Derivation of site-specific relationships between hydraulic parameters and p-wave velocities based on hydraulic and seismic tomography (open access)

Derivation of site-specific relationships between hydraulic parameters and p-wave velocities based on hydraulic and seismic tomography

In this study, hydraulic and seismic tomographic measurements were used to derive a site-specific relationship between the geophysical parameter p-wave velocity and the hydraulic parameters, diffusivity and specific storage. Our field study includes diffusivity tomograms derived from hydraulic travel time tomography, specific storage tomograms, derived from hydraulic attenuation tomography, and p-wave velocity tomograms, derived from seismic tomography. The tomographic inversion was performed in all three cases with the SIRT (Simultaneous Iterative Reconstruction Technique) algorithm, using a ray tracing technique with curved trajectories. The experimental set-up was designed such that the p-wave velocity tomogram overlaps the hydraulic tomograms by half. The experiments were performed at a wellcharacterized sand and gravel aquifer, located in the Leine River valley near Göttingen, Germany. Access to the shallow subsurface was provided by direct-push technology. The high spatial resolution of hydraulic and seismic tomography was exploited to derive representative site-specific relationships between the hydraulic and geophysical parameters, based on the area where geophysical and hydraulic tests were performed. The transformation of the p-wave velocities into hydraulic properties was undertaken using a k-means cluster analysis. Results demonstrate that the combination of hydraulic and geophysical tomographic data is a promising approach to improve hydrogeophysical site characterization.
Date: January 10, 2012
Creator: Brauchler, R.; Doetsch, J.; Dietrich, P. & Sauter, M.
Object Type: Article
System: The UNT Digital Library
The Express-Star (Chickasha, Okla.), Ed. 1 Friday, August 10, 2012 (open access)

The Express-Star (Chickasha, Okla.), Ed. 1 Friday, August 10, 2012

Daily newspaper from Chickasha, Oklahoma that includes local, state, and national news along with advertising.
Date: August 10, 2012
Creator: Bright, James
Object Type: Newspaper
System: The Gateway to Oklahoma History
The Express-Star (Chickasha, Okla.), Ed. 1 Saturday, November 10, 2012 (open access)

The Express-Star (Chickasha, Okla.), Ed. 1 Saturday, November 10, 2012

Daily newspaper from Chickasha, Oklahoma that includes local, state, and national news along with advertising.
Date: November 10, 2012
Creator: Bright, James
Object Type: Newspaper
System: The Gateway to Oklahoma History
The Express-Star (Chickasha, Okla.), Ed. 1 Wednesday, October 10, 2012 (open access)

The Express-Star (Chickasha, Okla.), Ed. 1 Wednesday, October 10, 2012

Daily newspaper from Chickasha, Oklahoma that includes local, state, and national news along with advertising.
Date: October 10, 2012
Creator: Bright, James
Object Type: Newspaper
System: The Gateway to Oklahoma History