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Cryogenic safety aspect of the low -$\beta$ magnest systems at the Large Hadron Collider (LHC)

Description: The low-{beta} magnet systems are located in the LHC insertion regions around the four interaction points. They are the key elements in the beams focusing/defocusing process and will allow proton collisions at a luminosity of up to 10{sup 34}cm{sup -2}s{sup -1}. Large radiation dose deposited at the proximity of the beam collisions dictate stringent requirements for the design and operation of the systems. The hardware commissioning phase of the LHC was completed in the winter of 2010 and permi… more
Date: July 1, 2010
Creator: Darve, C.
Partner: UNT Libraries Government Documents Department
open access

Determination of the spin-flip time in ferromagnetic SrRuO3 from time-resolved Kerr measurements

Description: We report time-resolved Kerr effect measurements of magnetization dynamics in ferromagnetic SrRuO{sub 3}. We observe that the demagnetization time slows substantially at temperatures within 15K of the Curie temperature, which is {approx} 150K. We analyze the data with a phenomenological model that relates the demagnetization time to the spin flip time. In agreement with our observations the model yields a demagnetization time that is inversely proportional to T-T{sub c}. We also make a direct c… more
Date: July 30, 2010
Creator: Kantner, C. L. S.; Langner, M. C.; Siemons, W.; Blok, J. L.; Koster, G.; Rijnders, A.J. H. M. et al.
Partner: UNT Libraries Government Documents Department
open access

Structural and Morphological Properties of Carbon Supports: Effect on Catalyst Degradation

Description: The object of this work was to identify correlations between performance losses of Pt electrocatalysts on carbon support materials and the chemical and morphological parameters that describe them. Accelerated stress testing, with an upper potential of 1.2 V, was used to monitor changes to cathode properties, including kinetic performance and effective platinum surface area losses. The structure and chemical compositions were studied using X-ray Photoelectron Spectroscopy and Scanning Electron M… more
Date: July 1, 2010
Creator: Patel, Anant; Artyushkova, Kateryna; Atanassov, Plamen; Young, Alan; Dutta, Monica; Ahmad, Zaid et al.
Partner: UNT Libraries Government Documents Department
open access

Performance of Integrated Systems of Automated Roller Shade Systems and Daylight Responsive Dimming Systems

Description: Daylight responsive dimming systems have been used in few buildings to date because they require improvements to improve reliability. The key underlying factor contributing to poor performance is the variability of the ratio of the photosensor signal to daylight workplane illuminance in accordance with sun position, sky condition, and fenestration condition. Therefore, this paper describes the integrated systems between automated roller shade systems and daylight responsive dimming systems with… more
Date: July 8, 2010
Creator: Park, Byoung-Chul; Choi, An-Seop; Jeong, Jae-Weon & Lee, Eleanor S.
Partner: UNT Libraries Government Documents Department
open access

Nonlinear Broadband Photoluminescence of Graphene Induced by Femtosecond Laser Irradiation

Description: Upon femtosecond laser irradiation, a bright, broadband photoluminescence is observed from graphene at frequencies well above the excitation frequency. Analyses show that it arises from radiative recombination of a broad distribution of nonequilibrium electrons and holes, generated by rapid scattering between photoexcited carriers within tens of femtoseconds after the optical excitation. Its highly unusual characteristics come from the unique electronic and structural properties of graphene.
Date: July 1, 2010
Creator: Liu, Wei-Tao; Wu, S.W.; Schuck, P.J.; Salmeron, Miquel; Shen, Y.R. & Wang, F.
Partner: UNT Libraries Government Documents Department
open access

Engineering the Electronic Band Structure for Multiband Solar Cells

Description: Using the unique features of the electronic band structure of GaNxAs1-x alloys, we have designed, fabricated and tested a multiband photovoltaic device. The device demonstrates an optical activity of three energy bands that absorb, and convert into electrical current, the crucial part of the solar spectrum. The performance of the device and measurements of electroluminescence, quantum efficiency and photomodulated reflectivity are analyzed in terms of the Band Anticrossing model of the electron… more
Date: July 12, 2010
Creator: Lopez, N.; Reichertz, L. A.; Yu, K. M.; Campman, K. & Walukiewicz, W.
Partner: UNT Libraries Government Documents Department
open access

From many body wee partons dynamics to perfect fluid: a standard model for heavy ion collisions

Description: We discuss a standard model of heavy ion collisions that has emerged both from experimental results of the RHIC program and associated theoretical developments. We comment briefly on the impact of early results of the LHC program on this picture. We consider how this standard model of heavy ion collisions could be solidified or falsified in future experiments at RHIC, the LHC and a future Electro-Ion Collider.
Date: July 22, 2010
Creator: Venugopalan, R.
Partner: UNT Libraries Government Documents Department
open access

2010 Thin Film & Small Scale Mechanical Behavior Gordon Research Conference

Description: Over the past decades, it has been well established that the mechanical behavior of materials changes when they are confined geometrically at least in one dimension to small scale. It is the aim of the 2010 Gordon Conference on 'Thin Film and Small Scale Mechanical Behavior' to discuss cutting-edge research on elastic, plastic and time-dependent deformation as well as degradation mechanisms like fracture, fatigue and wear at small scales. As in the past, the conference will benefit from contrib… more
Date: July 30, 2010
Creator: Balk, Dr. Thomas
Partner: UNT Libraries Government Documents Department
open access

Analysis of biostimulated microbial communities from two field experiments reveals temporal and spatial differences in proteome profiles

Description: Stimulated by an acetate-amendment field experiment conducted in 2007, anaerobic microbial populations in the aquifer at the Rifle Integrated Field Research Challenge site in Colorado reduced mobile U(VI) to insoluble U(IV). During this experiment, planktonic biomass was sampled at various time points to quantitatively evaluate proteomes. In 2008, an acetate-amended field experiment was again conducted in a similar manner to the 2007 experiment. As there was no comprehensive metagenome sequence… more
Date: July 15, 2010
Creator: Callister, S. J.; Wilkins, M. J.; Nicora, C. D.; Williams, K. H.; Banfield, J. F.; VerBerkmoes, N. C. et al.
Partner: UNT Libraries Government Documents Department
open access

Methane hydrate distribution from prolonged and repeated formation in natural and compacted sand samples: X-ray CT observations

Description: To study physical properties of methane gas hydrate-bearing sediments, it is necessary to synthesize laboratory samples due to the limited availability of cores from natural deposits. X-ray computed tomography (CT) and other observations have shown gas hydrate to occur in a number of morphologies over a variety of sediment types. To aid in understanding formation and growth patterns of hydrate in sediments, methane hydrate was repeatedly formed in laboratory-packed sand samples and in a natural… more
Date: July 1, 2010
Creator: Rees, E.V.L.; Kneafsey, T.J. & Seol, Y.
Partner: UNT Libraries Government Documents Department
open access

Cleanroom Energy Efficiency: Metrics and Benchmarks

Description: Cleanrooms are among the most energy-intensive types of facilities. This is primarily due to the cleanliness requirements that result in high airflow rates and system static pressures, as well as process requirements that result in high cooling loads. Various studies have shown that there is a wide range of cleanroom energy efficiencies and that facility managers may not be aware of how energy efficient their cleanroom facility can be relative to other cleanroom facilities with the same cleanli… more
Date: July 7, 2010
Creator: Initiative, International SEMATECH Manufacturing; Mathew, Paul A.; Tschudi, William; Sartor, Dale & Beasley, James
Partner: UNT Libraries Government Documents Department
open access

Cadmium Manganese Telluride (Cd1-xMnxTe): A potential material for room-temperature radiation detectors

Description: Cadmium Manganese Telluride (CdMnTe) recently emerged as a promising material for room-temperature X- and gamma-ray detectors. It offers several potential advantages over CdZnTe. Among them is its optimal tunable band gap ranging from 1.7-2.2 eV, and its relatively low (< 50%) content of Mn compared to that of Zn in CdZnTe that assures this favorable band-gap range. Another important asset is the segregation coefficient of Mn in CdTe that is approximately unity compared to 1.35 for Zn in CdZ… more
Date: July 11, 2010
Creator: Hossain, A.; Cui, Y.; Bolotnikov, A.; Camarda, G.; Yang, G.; Kim, K. H. et al.
Partner: UNT Libraries Government Documents Department
open access

2010 Membranes: Materials & Processes Gordon Research Conference

Description: The GRC series on Membranes: Materials and Processes have gained significant international recognition, attracting leading experts on membranes and other related areas from around the world. It is now known for being an interdisciplinary and synergistic meeting. The next summer's edition will keep with the past tradition and include new, exciting aspects of material science, chemistry, chemical engineering, computer simulation with participants from academia, industry and national laboratories.… more
Date: July 30, 2010
Creator: Lin, Jerry
Partner: UNT Libraries Government Documents Department
open access

A molecularly defined duplication set for the X chromosome of Drosophila melanogaster

Description: We describe a molecularly defined duplication kit for the X chromosome of Drosophila melanogaster. A set of 408 overlapping P[acman] BAC clones was used to create small duplications (average length 88 kb) covering the 22-Mb sequenced portion of the chromosome. The BAC clones were inserted into an attP docking site on chromosome 3L using C31 integrase, allowing direct comparison of different transgenes. The insertions complement 92% of the essential and viable mutations and deletions tested, dem… more
Date: July 22, 2010
Creator: Venken, Koen J. T.; Popodi, Ellen; Holtzman, Stacy L.; Schulze, Karen L.; Park, Soo; Carlson, Joseph W. et al.
Partner: UNT Libraries Government Documents Department
open access

Complete Calculation of Evaluated Maxwellian-Averaged Cross Sections and Their Uncertainties for S-Process Nucleosynthesis

Description: Present contribution represents a significant improvement of our previous calculation of Maxwellian-averaged cross sections and astrophysical reaction rates. Addition of newly-evaluated neutron reaction libraries, such as ROSFOND and Low-Fidelity Covariance Project, and improvements in data processing techniques allowed us to extend it for entire range of sprocess nuclei, calculate Maxwellian-averaged cross section uncertainties for the first time, and provide additional insights on all current… more
Date: July 19, 2010
Creator: Pritychenko, B.
Partner: UNT Libraries Government Documents Department
open access

Intra- and interspecific responses to Rafinesque’s big-eared bat (Corynorhinus rafinesquii) social calls.

Description: Bats respond to the calls of conspecifics as well as to calls of other species; however, few studies have attempted to quantify these responses or understand the functions of these calls. We tested the response of Rafinesque’s big-eared bats (Corynorhinus rafinesquii) to social calls as a possible method to increase capture success and to understand the function of social calls. We also tested if calls of bats within the range of the previously designated subspecies differed, if the responses o… more
Date: July 1, 2010
Creator: Loeb, Susan, C. & Britzke, Eric, R.
Partner: UNT Libraries Government Documents Department
open access

SINGLE MOLECULE APPROACHES TO BIOLOGY, 2010 GORDON RESEARCH CONFERENCE, JUNE 27-JULY 2, 2010, ITALY

Description: The 2010 Gordon Conference on Single-Molecule Approaches to Biology focuses on cutting-edge research in single-molecule science. Tremendous technical developments have made it possible to detect, identify, track, and manipulate single biomolecules in an ambient environment or even in a live cell. Single-molecule approaches have changed the way many biological problems are addressed, and new knowledge derived from these approaches continues to emerge. The ability of single-molecule approaches to… more
Date: July 9, 2010
Creator: Moerner, Professor William
Partner: UNT Libraries Government Documents Department
open access

2010 POLYMER PHYSICS - JUNE 27 - JULY 2, 2010

Description: The 2010 Gordon Research Conference on Polymer Physics will provide outstanding lectures and discussions in this critical field that impacts every industrial sector from electronics to transportation to medicine to textiles to energy generation and storage. Fundamental topics range from mechanical properties of soft gels to new understanding in polymer crystallization to energy conversion and transmission to simulating polymer dynamics at the nanoscale. This international conference will featur… more
Date: July 2, 2010
Creator: Winey, Karen
Partner: UNT Libraries Government Documents Department
open access

Ice Formation in Gas-Diffusion Layers

Description: Under sub-freezing conditions, ice forms in the gas-diffusion layer (GDL) of a proton exchange membrane fuel cell (PEMFC) drastically reducing cell performance. Although a number of strategies exist to prevent ice formation, there is little fundamental understanding of the mechanisms of freezing within PEMFC components. Differential scanning calorimetry (DSC) is used to elucidate the effects of hydrophobicity (Teflon® loading) and water saturation on the rate of ice formation within three comme… more
Date: July 10, 2010
Creator: Dursch, Thomas; Radke, Clayton J. & Weber, Adam Z.
Partner: UNT Libraries Government Documents Department
open access

Assessing Equivalent Viscous Damping Using Piping System Test Results

Description: The specification of damping for nuclear piping systems subject to seismic-induced motions has been the subject of many studies and much controversy. Damping estimation based on test data can be influenced by numerous factors, consequently leading to considerable scatter in damping estimates in the literature. At present, nuclear industry recommendations and nuclear regulatory guidance are not consistent on the treatment of damping for analysis of nuclear piping systems. Therefore, there is sti… more
Date: July 18, 2010
Creator: Nie, J. & Morante, R.
Partner: UNT Libraries Government Documents Department
open access

Multi-Level Bitmap Indexes for Flash Memory Storage

Description: Due to their low access latency, high read speed, and power-efficient operation, flash memory storage devices are rapidly emerging as an attractive alternative to traditional magnetic storage devices. However, tests show that the most efficient indexing methods are not able to take advantage of the flash memory storage devices. In this paper, we present a set of multi-level bitmap indexes that can effectively take advantage of flash storage devices. These indexing methods use coarsely binned in… more
Date: July 23, 2010
Creator: Wu, Kesheng; Madduri, Kamesh & Canon, Shane
Partner: UNT Libraries Government Documents Department
open access

Full multiple scattering analysis of XANES at the Cd L3 and O K edges in CdO films combined with a soft-x-ray emission investigation

Description: X-ray absorption near edge structure (XANES) at the cadmium L3 and oxygen K edges for CdO thin films grown by pulsed laser deposition method, is interpreted within the real-space multiple scattering formalism, FEFF code. The features in the experimental spectra are well reproduced by calculations for a cluster of about six and ten coordination shells around the absorber for L3 edge of Cd and K edge of O, respectively. The calculated projected electronic density of states is found to be in good … more
Date: July 5, 2010
Creator: Demchenko, I. N.; Denlinger, J. D.; Chernyshova, M.; Yu, K. M.; Speaks, D. T.; Olalde-Velasco, P. et al.
Partner: UNT Libraries Government Documents Department
open access

A nanocrystal strain gauge for luminescence detection of mechanical forces

Description: Local microscale stresses play a crucial role in inhomogeneous mechanical processes from cell motility to material failure. However, it remains difficult to spatially resolve stress at these small length scales. While contact-probe and non-contact based techniques have been used to quantify local mechanical behavior in specific systems with high stiffness or stress and spatial resolution, these methods cannot be used to study a majority of micromechanical systems due to spectroscopic and geomet… more
Date: July 26, 2010
Creator: Choi, Charina; Koski, Kristie; Olson, Andrew & Alivisatos, Paul
Partner: UNT Libraries Government Documents Department
open access

Energy-Water Nexus

Description: Conclusions of this presentation are: (1) energy and water are interconnected; (2) new energy sources will place increased demands on water supplies; (3) existing energy sources will be subjected to increasing restrictions on their water use; and (4) integrated decision support tools will need to be developed to help policy makers decide which policies and advanced technologies can address these issues.
Date: July 26, 2010
Creator: Horak, W.
Partner: UNT Libraries Government Documents Department
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