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The Effects of a Supportive Communication Training Workshop on the Verbal Behavior of Behavior Analysis (open access)

The Effects of a Supportive Communication Training Workshop on the Verbal Behavior of Behavior Analysis

Article on the effects of a supportive communication training workshop on the verbal behavior of behavior analysts.
Date: May 1, 2010
Creator: Blell, Zainab D.; Ala'i-Rosales, Shahla & Rosales-Ruiz, Jesus
System: The UNT Digital Library
Templated Growth of Hexagonal Nickel Carbide Nanocrystals on Vertically Aligned Carbon Nanotubes (open access)

Templated Growth of Hexagonal Nickel Carbide Nanocrystals on Vertically Aligned Carbon Nanotubes

Article discussing the templated growth of hexagonal nickel carbon nanocrystals on vertically aligned carbon nanotubes.
Date: May 18, 2010
Creator: Hwang, Jun Y.; Singh, Antariksh; Chaudhari, Mrunalkumar; Tiley, Jaimie S.; Zhu, Y. T. (Yuntian T.), 1963-; Du, Jincheng et al.
System: The UNT Digital Library
Calculations Predict That Carbon Tunneling Allows the Degenerate Cope Rearrangement of Semibullvalene to Occur Rapidly at Cryogenic Temperatures (open access)

Calculations Predict That Carbon Tunneling Allows the Degenerate Cope Rearrangement of Semibullvalene to Occur Rapidly at Cryogenic Temperatures

Article on calculations predicting that carbon tunneling allows the degenerate cope rearrangement of semibullvalene to occur rapidly at cryogenic temperatures.
Date: May 27, 2010
Creator: Zhang, Xue; Hrovat, David A. & Borden, Weston T.
System: The UNT Digital Library
Femtosecond wave-packet dynamics in cesium dimers studied through controlled stimulated emission (open access)

Femtosecond wave-packet dynamics in cesium dimers studied through controlled stimulated emission

Article on femtosecond wave-packet dynamics in cesium dimers studied through controlled stimulated emission.
Date: May 12, 2010
Creator: Yuan, Luqi; Ariunbold, Gombojav O.; Murawski, Robert K.; Pestov, Dmitry; Wang, Xi; Patnaik, Anil K. et al.
System: The UNT Digital Library
Classifying genes to the correct Gene Ontology Slim term in Saccharomyces cerevisiae using neighbouring genes with classification learning (open access)

Classifying genes to the correct Gene Ontology Slim term in Saccharomyces cerevisiae using neighbouring genes with classification learning

Article discussing research on classifying genes to the correct gene ontology slim term in Saccharomyces cerevisiae using neighbouring genes with classification learning.
Date: May 28, 2010
Creator: Amthauer, Heather A. & Tsatsoulis, C. (Costas), 1962-
System: The UNT Digital Library
Solubility of Phenanthrene in Ternary Mixtures of C1-C4 Alcohols at 298.2 K (open access)

Solubility of Phenanthrene in Ternary Mixtures of C1-C4 Alcohols at 298.2 K

This article discusses the solubility of phenanthrene in ternary mixtures of C1-C4 alcohols at 298.2 K.
Date: May 21, 2010
Creator: Fakhree, Mohammad Amin Abolghassemi; Acree, William E. (William Eugene) & Jouyban, Abolghasem
System: The UNT Digital Library
Solubility of Anthracene in Binary and Ternary Mixtures of Cyclohexanone, Ethyl Acetate, and Methanol at 298.2 K (open access)

Solubility of Anthracene in Binary and Ternary Mixtures of Cyclohexanone, Ethyl Acetate, and Methanol at 298.2 K

This article discusses the solubility of anthracene in binary and ternary mixtures of cyclohexanone, ethyl acetate, and methanol at 298.2 K.
Date: May 10, 2010
Creator: Jouyban, Abolghasem; Manzoori, Jamshid L.; Panahi-Azar, Vahid; Soleymani, Jafar; Fakhree, Mohammad Amin Abolghassemi; Shayanfar, Ali et al.
System: The UNT Digital Library
Novel Geometries for the LHC Crab Cavity (open access)

Novel Geometries for the LHC Crab Cavity

The planned luminosity upgrade to LHC is likely to necessitate a large crossing angle and a local crab crossing scheme. For this scheme crab cavities align bunches prior to collision. The scheme requires at least four such cavities, a pair on each beam line either side of the interaction point (IP). Upstream cavities initiate rotation and downstream cavities cancel rotation. Cancellation is usually done at a location where the optics has re-aligned the bunch. The beam line separation near the IP necessitates a more compact design than is possible with elliptical cavities such as those used at KEK. The reduction in size must be achieved without an increase in the operational frequency to maintain compatibility with the long bunch length of the LHC. This paper proposes a suitable superconducting variant of a four rod coaxial deflecting cavity (to be phased as a crab cavity), and presents analytical models and simulations of suitable designs.
Date: May 1, 2010
Creator: B. Hall,G. Burt,C. Lingwood,Robert Rimmer,Haipeng Wang; Hall, B.; Burt, G.; Lingwood, C.; Rimmer, Robert & Wang, Haipeng
System: The UNT Digital Library
The Status of De-Inventory of Security Category I/II Nuclear Materials at Lawrence Livermore National Laboratory (LLNL) (open access)

The Status of De-Inventory of Security Category I/II Nuclear Materials at Lawrence Livermore National Laboratory (LLNL)

None
Date: May 13, 2010
Creator: Riley, D C & Dodson, K
System: The UNT Digital Library
Electron Cloud at Low Emittance in CesrTA (open access)

Electron Cloud at Low Emittance in CesrTA

The Cornell Electron Storage Ring (CESR) has been reconfigured as a test accelerator (CesrTA) for a program of electron cloud (EC) research at ultra low emittance. The instrumentation in the ring has been upgraded with local diagnostics for measurement of cloud density and with improved beam diagnostics for the characterization of both the low emittance performance and the beam dynamics of high intensity bunch trains interacting with the cloud. A range of EC mitigation methods have been deployed and tested and their effectiveness is discussed. Measurements of the electron cloud's effect on the beam under a range of conditions are discussed along with the simulations being used to quantitatively understand these results.
Date: May 23, 2010
Creator: Alexander, J. P.; Billing, M. G.; Calvey, J.; Crittenden, J. A.; Dugan, G.; Eggert, N. et al.
System: The UNT Digital Library
Daemen Alternative Energy/Geothermal Technologies Demonstration Program Erie County (open access)

Daemen Alternative Energy/Geothermal Technologies Demonstration Program Erie County

The purpose of the Daemen Alternative Energy/Geothermal Technologies Demonstration Project is to demonstrate the use of geothermal technology as model for energy and environmental efficiency in heating and cooling older, highly inefficient buildings. The former Marian Library building at Daemen College is a 19,000 square foot building located in the center of campus. Through this project, the building was equipped with geothermal technology and results were disseminated. Gold LEED certification for the building was awarded. 1) How the research adds to the understanding of the area investigated. This project is primarily a demonstration project. Information about the installation is available to other companies, organizations, and higher education institutions that may be interested in using geothermal energy for heating and cooling older buildings. 2) The technical effectiveness and economic feasibility of the methods or techniques investigated or demonstrated. According to the modeling and estimates through Stantec, the energy-efficiency cost savings is estimated at 20%, or $24,000 per year. Over 20 years this represents $480,000 in unrestricted revenue available for College operations. See attached technical assistance report. 3) How the project is otherwise of benefit to the public. The Daemen College Geothermal Technologies Ground Source Heat Pumps project sets a standard for …
Date: May 20, 2010
Creator: Robert C. Beiswanger, Jr.
System: The UNT Digital Library
Preliminary Evaluation of the Section 1603 Treasury Grant Program for Renewable Power Projects in the United States (open access)

Preliminary Evaluation of the Section 1603 Treasury Grant Program for Renewable Power Projects in the United States

This article evaluates the first year of the Section 1603 Treasury cash grant program, which enables renewable power projects in the U.S. to elect cash grants in lieu of the federal tax credits that are otherwise available. To date, the program has been heavily subscribed, particularly by wind power projects, which had received 86% of the nearly $2.6 billion in grants that had been disbursed as of March 1, 2010. As of that date, 6.2 GW of the 10 GW of new wind capacity installed in the U.S. in 2009 had applied for grants in lieu of production tax credits. Roughly 2.4 GW of this wind capacity may not have otherwise been built in 2009 absent the grant program; this 2.4 GW may have supported approximately 51,600 short-term full-time-equivalent (FTE) gross job-years in the U.S. during the construction phase of these wind projects, and 3,860 longterm FTE gross jobs during the operational phase. The program’s popularity stems from the significant economic value that it provides to renewable power projects, relative to the otherwise available tax credits. Although grants reward investment rather than efficient performance, this evaluation finds no evidence at this time of either widespread “gold-plating” or performance problems.
Date: May 5, 2010
Creator: Bolinger, Mark; Wiser, Ryan & Darghouth, Naim
System: The UNT Digital Library
Infrared birefringence imaging of residual stress and bulk defects in multicrystalline silicon (open access)

Infrared birefringence imaging of residual stress and bulk defects in multicrystalline silicon

This manuscript concerns the application of infrared birefringence imaging (IBI) to quantify macroscopic and microscopic internal stresses in multicrystalline silicon (mc-Si) solar cell materials. We review progress to date, and advance four closely related topics. (1) We present a method to decouple macroscopic thermally-induced residual stresses and microscopic bulk defect related stresses. In contrast to previous reports, thermally-induced residual stresses in wafer-sized samples are generally found to be less than 5 MPa, while defect-related stresses can be several times larger. (2) We describe the unique IR birefringence signatures, including stress magnitudes and directions, of common microdefects in mc-Si solar cell materials including: {beta}-SiC and {beta}-Si{sub 3}N{sub 4} microdefects, twin bands, nontwin grain boundaries, and dislocation bands. In certain defects, local stresses up to 40 MPa can be present. (3) We relate observed stresses to other topics of interest in solar cell manufacturing, including transition metal precipitation, wafer mechanical strength, and minority carrier lifetime. (4) We discuss the potential of IBI as a quality-control technique in industrial solar cell manufacturing.
Date: May 5, 2010
Creator: Ganapati, Vidya; Schoenfelder, Stephan; Castellanos, Sergio; Oener, Sebastian; Koepge, Ringo; Sampson, Aaron et al.
System: The UNT Digital Library
Long Range Active Detection of HEU Based on Thermal Neutron Multiplication (open access)

Long Range Active Detection of HEU Based on Thermal Neutron Multiplication

We report on the results of measurements of proton irradiation on a series of targets at Brookhaven National Laboratory’s (BNL) Alternate Gradient Synchrotron Facility (AGS), in collaboration with LANL and SNL. We examined the prompt radiation environment in the tunnel for the DTRA-sponsored series (E 972), which investigated the penetration of air and subsequent target interaction of 4 GeV proton pulses. Measurements were made by means of an organic scintillator with a 500 MHz bandwidth system. We found that irradiation of a depleted uranium (DU) target resulted in a large gamma-ray signal in the 100-500 µsec time region after the proton flash when the DU was surrounded by polyethylene, but little signal was generated if it was surrounded by boron-loaded polyethylene. Subsequent Monte Carlo (MCNPX) calculations indicated that the source of the signal was consistent with thermal neutron capture in DU. The MCNPX calculations also indicated that if one were to perform the same experiment with a highly enriched uranium (HEU) target there would be a distinctive fast neutron yield in this 100-500 µsec time region from thermal neutron-induced fission. The fast neutrons can be recorded by the same direct current system and differentiated from gamma ray pulses in organic …
Date: May 24, 2010
Creator: L., Forman; I., Dioszegi; Salwen, C. & and Vanier, P.E.
System: The UNT Digital Library
New Particle-in-Cell Code for Numerical Simulation of Coherent Synchrotron Radiation (open access)

New Particle-in-Cell Code for Numerical Simulation of Coherent Synchrotron Radiation

We present a first look at the new code for self-consistent, 2D simulations of beam dynamics affected by the coherent synchrotron radiation. The code is of the particle-in-cell variety: the beam bunch is sampled by point-charge particles, which are deposited on the grid; the corresponding forces on the grid are then computed using retarded potentials according to causality, and interpolated so as to advance the particles in time. The retarded potentials are evaluated by integrating over the 2D path history of the bunch, with the charge and current density at the retarded time obtained from interpolation of the particle distributions recorded at discrete timesteps. The code is benchmarked against analytical results obtained for a rigid-line bunch. We also outline the features and applications which are currently being developed.
Date: May 1, 2010
Creator: Balsa Terzic, Rui Li
System: The UNT Digital Library
BEAM CONTAINMENT SYSTEM FOR NSLS-II (open access)

BEAM CONTAINMENT SYSTEM FOR NSLS-II

The shielding design for the NSLS-II will provide adequate protection for the full injected beam loss in two periods of the ring around the injection point, but the remainder of the ring is shielded for lower losses of {le} 10% full beam. This will require a system to insure that beam losses don't exceed these levels for a period of time that could cause excessive radiation levels outside the shield walls. This beam containment system will measure, provide a level of control and alarm indication of the beam power losses along the beam path from the source (e-gun, linac) thru the injection system and the storage ring. This system will consist of collimators that will provide limits to (and potentially to measure) the beam miss-steering and control the loss points of the charge and monitors that will measure the average beam current losses along the beam path and alarm when this beam power loss exceeds the level set by the shielding specifications. This will require some new ideas in beam loss detection capability and collimation. The initial planning and R&D program will be presented.
Date: May 23, 2010
Creator: Kramer, S. L.; Casey, W. & Job, P. K.
System: The UNT Digital Library
Novel Geometries for the LHC Crab Cavity (open access)

Novel Geometries for the LHC Crab Cavity

The planned luminosity upgrade to LHC is likely to necessitate a large crossing angle and a local crab crossing scheme. For this scheme crab cavities align bunches prior to collision. The scheme requires at least four such cavities, a pair on each beam line either side of the interaction point (IP). Upstream cavities initiate rotation and downstream cavities cancel rotation. Cancellation is usually done at a location where the optics has re-aligned the bunch. The beam line separation near the IP necessitates a more compact design than is possible with elliptical cavities such as those used at KEK. The reduction in size must be achieved without an increase in the operational frequency to maintain compatibility with the long bunch length of the LHC. This paper proposes a suitable superconducting variant of a four rod coaxial deflecting cavity (to be phased as a crab cavity), and presents analytical models and simulations of suitable designs.
Date: May 23, 2010
Creator: B. Hall, G. Burt, C. Lingwood, R. Rimmer, H. Wang
System: The UNT Digital Library
An imaging proton spectrometer for short-pulse laser plasma experiments (open access)

An imaging proton spectrometer for short-pulse laser plasma experiments

Ultra intense short pulse laser pulses incident on solid targets can generate energetic protons. In additions to their potentially important applications such as in cancer treatments and proton fast ignition, these protons are essential to understand the complex physics of intense laser plasma interaction. To better characterize these laser-produced protons, we designed and constructed a novel, spatially imaging proton spectrometer that will not only measure proton energy distribution with high resolution, but also provide its angular characteristics. The information obtained from this spectrometer compliments those from commonly used diagnostics including radiochromic film packs, CR39 nuclear track detectors, and non-imaging magnetic spectrometers. The basic characterizations and sample data from this instrument are presented.
Date: May 11, 2010
Creator: Chen, H.; Hazi, A.; van Maren, R.; Chen, S.; Fuchs, J.; Gauthier, M. et al.
System: The UNT Digital Library
RHIC BBLR measurements in 2009 (open access)

RHIC BBLR measurements in 2009

Long range beam-beam experiments were conducted during the Run 2009 in the Yellow and the Blue beams of the RHIC accelerator with DC wires. The effects of a long-range interaction with a DC wire on colliding and non-colliding bunches with the aid of beam losses, orbits, tunes were studied. Results from distance scans and an attempt to compensate a long-range interaction with a DC wire is presented. Two DC wires in the vertical plane were installed in the RHIC accelerator in 2006 with the aim of investigating long range (LR) beam-beam effects and a potential compensation. Extensive experiments were conducted focusing mainly on the effect of a wire on single ion beams from 2006-2009. A unique opportunity to compare the effect of the wire on colliding beams and compensation of a single LR beam-beam interaction were conducted in Run2009 with protons at 100 GeV. Due to aperture considerations for decreasing {beta}*, the Blue wire was removed during the shutdown after the Run2009 and the Yellow wire is foreseen to be removed in the near future. Therefore, these experiments serve as the final set of measurements for LR beam-beam with RHIC as a test bed. The relevant RHIC beam and lattice …
Date: May 23, 2010
Creator: Calaga, R.; Robert-Demolaize, G. & Fischer, W.
System: The UNT Digital Library
Electrodeposition of U and Pu on Thin C and Ti Substrates (open access)

Electrodeposition of U and Pu on Thin C and Ti Substrates

Physics experiments aimed at deducing key parameters for use in a variety of programs critical to the mission of the National Laboratories require actinide targets placed onto various substrates. The target material quantity and the substrate desired depend upon the type of experiment being designed. The physicist(s) responsible for the experimental campaign will consult with the radiochemistry staff as to the feasibility of producing a desired target/substrate combination. In this report they discuss the production of U and Pu targets on very thin C and Ti substrates. The techniques used, plating cells designed for, tips, and limits is discussed.
Date: May 19, 2010
Creator: Henderson, R. A. & Gostic, J. M.
System: The UNT Digital Library
Quantum efficiency temporal response and lifetime of a GaAs cathode in SRF electron gun (open access)

Quantum efficiency temporal response and lifetime of a GaAs cathode in SRF electron gun

RF electron guns with a strained super lattice GaAs cathode can generate polarized electron beam of higher brightness and lower emittance than do DC guns, due to their higher field gradient at the cathode's surface. In a normal conducting RF gun, the extremely high vaccum required by these cathodes can not be met. We report on an experiment with a superconducting SRF gun, which can maintain a vacuum of nearly 10-12 torr because of cryo-pumping at the temperature of 4.2K. With conventional activation, we obtained a QE of 3% at 532 nm, with lifetime of nearly 3 days in the preparation chamber. We plan to use this cathode in a 1.3 GHz 1/2 cell SRF gun to study its performance. In addition, we studied the multipacting at the location of cathode. A new model based on the Forkker-Planck equation which can estimate the bunch length of the electron beam is discussed in this paper. Future particle accelerators such as eRHIC and ILC require high brightness, high current polarized electrons Recently, using a superlattice crystal, the maximum polarization of 95% was reached. Activation with Cs,O lowers the electron affinity and makes it energetically possible for all the electrons excited in to …
Date: May 23, 2010
Creator: Wang, E.; Ben-Zvi, Ilan; Kewisch, J.; Burrill, A.; Rao, T.; Wu, Q. et al.
System: The UNT Digital Library
Task 1—Steam Oxidation (NETL-US) (open access)

Task 1—Steam Oxidation (NETL-US)

The proposed steam in let temperature in the Advanced Ultra Supercritical (A·USC) steam turbine is high enough (760°C) Ihat traditional turbine casing and valve body materials such as ferr;tic/manensitic steels will not suffice due to temperature lim itations of this class of materials. Cast versions of three traditionally wrought Ni-based superalloys (Haynes 263. Haynes 282, and Nimonic 105) were evaluated for use as casing or valve components for the next generation of industrial steam turbines. The full size castings are substantia l: 2-5,000 kg each half and on the order of 100 nun thick. Experimental castings were quite a bit smaller, but section size was retained and cooling rate controlled to produce equi valem microslruclUre •. A multi_step homogenization heat treatment was d~ve loped to better disperse the al loy constituents. These castings were subsequently evaluated by characterizing their microstructure as well as their steam oxidation resistance (al 760 and 800 "C).
Date: May 1, 2010
Creator: Holcomb, G. R.
System: The UNT Digital Library
Predicting Image Blur in Proton Radiography: Comparisons Between Measurements and Monte Carlo Simulations (open access)

Predicting Image Blur in Proton Radiography: Comparisons Between Measurements and Monte Carlo Simulations

Given the cost and lead-times involved in high-energy proton radiography, it is prudent to model proposed radiographic experiments to see if the images predicted would return useful information. We recently modified our raytracing transmission radiography modeling code HADES to perform simplified Monte Carlo simulations of the transport of protons in a proton radiography beamline. Beamline objects include the initial diffuser, vacuum magnetic fields, windows, angle-selecting collimators, and objects described as distorted 2D (planar or cylindrical) meshes or as distorted 3D hexahedral meshes. We present an overview of the algorithms used for the modeling and code timings for simulations through typical 2D and 3D meshes. We next calculate expected changes in image blur as scattering materials are placed upstream and downstream of a resolution test object (a 3 mm thick sheet of tantalum, into which 0.4 mm wide slits have been cut), and as the current supplied to the focusing magnets is varied. We compare and contrast the resulting simulations with the results of measurements obtained at the 800 MeV Los Alamos LANSCE Line-C proton radiography facility.
Date: May 7, 2010
Creator: Schach von Wittenau, Alexis E.; Aufderheide, Maurice B., III & Henderson, Gary L.
System: The UNT Digital Library
500 MW X-BAND RF SYSTEM OF A 0.25 GEV ELECTRON LINAC FOR ADVANCED COMPTON SCATTERING SOURCE APPLICATION (open access)

500 MW X-BAND RF SYSTEM OF A 0.25 GEV ELECTRON LINAC FOR ADVANCED COMPTON SCATTERING SOURCE APPLICATION

A Mono-Energetic Gamma-Ray (MEGa-Ray) Compton scattering light source is being developed at LLNL in collaboration with SLAC National Accelerator Laboratory. The electron beam for the Compton scattering interaction will be generated by a X-band RF gun and a X-band LINAC at the frequency of 11.424 GHz. High power RF in excess of 500 MW is needed to accelerate the electrons to energy of 250 MeV or greater for the interaction. Two high power klystron amplifiers, each capable of generating 50 MW, 1.5 msec pulses, will be the main high power RF sources for the system. These klystrons will be powered by state of the art solid-state high voltage modulators. A RF pulse compressor, similar to the SLED II pulse compressor, will compress the klystron output pulse with a power gain factor of five. For compactness consideration, we are looking at a folded waveguide setup. This will give us 500 MW at output of the compressor. The compressed pulse will then be distributed to the RF gun and to six traveling wave accelerator sections. Phase and amplitude control are located at the RF gun input and additional control points along the LINAC to allow for parameter control during operation. This high …
Date: May 12, 2010
Creator: Chu, T S; Anderson, S G; Gibson, D J; Hartemann, F V; Marsh, R A; Siders, C et al.
System: The UNT Digital Library