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INSTALLATION OF BUBBLERS IN THE SAVANNAH RIVER SITED DEFENSE WASTE PROCESSING FACILITY MELTER

Description: Savannah River Remediation (SRR) LLC assumed the liquid waste contract at the Savannah River Site (SRS) in the summer of 2009. The main contractual agreement was to close 22 High Level Waste (HLW) tanks in eight years. To achieve this aggressive commitment, faster waste processing throughout the SRS liquid waste facilities will be required. Part of the approach to achieve faster waste processing is to increase the canister production rate of the Defense Waste Processing Facility (DWPF) from app… more
Date: December 8, 2010
Creator: Smith, M. & Iverson, D.
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

The Importance of High Temporal Resolution in Modeling Renewable Energy Penetration Scenarios

Description: Traditionally, modeling investment and dispatch problems in electricity economics has been limited by computation power. Due to this limitation, simplifications are applied. One common practice, for example, is to reduce the temporal resolution of the dispatch by clustering similar load levels. The increase of intermittent electricity from renewable energy sources (RES-E) changes the validity of this assumption. RES-E already cover a certain amount of the total demand. This leaves an increasing… more
Date: October 8, 2010
Creator: Nicolosi, Marco; Mills, Andrew D & Wiser, Ryan H
Partner: UNT Libraries Government Documents Department
open access

Livermore Lab's giant laser system will bring star power to Earth

Description: In the 50 years since the laser was first demonstrated in Malibu, California, on May 16, 1960, Lawrence Livermore National Laboratory (LLNL) has been a world leader in laser technology and the home for many of the world's most advanced laser systems. That tradition continues today at LLNL's National Ignition Facility (NIF), the world's most energetic laser system. NIF's completion in March 2009 not only marked the dawn of a new era of scientific research - it could also prove to be the next big… more
Date: April 8, 2010
Creator: Moses, Edward
Partner: UNT Libraries Government Documents Department
open access

AFFECTS OF MECHANICAL MILLING AND METAL OXIDE ADDITIVES ON SORPTION KINETICS OF 1:1 LiNH2/MgH2 MIXTURE

Description: The destabilized complex hydride system composed of LiNH{sub 2}:MgH{sub 2} (1:1 molar ratio) is one of the leading candidates of hydrogen storage with a reversible hydrogen storage capacity of 8.1 wt%. A low sorption enthalpy of {approx}32 kJ/mole H{sub 2} was first predicted by Alapati et al. utilizing first principle density function theory (DFT) calculations and has been subsequently confirmed empirically by Lu et al. through differential thermal analysis (DTA). This enthalpy suggests that f… more
Date: December 8, 2010
Creator: Erdy, C.; Anton, D. & Gray, J.
Partner: UNT Libraries Government Documents Department
open access

Electron-Cloud Build-Up: Theory and Data

Description: We present a broad-brush survey of the phenomenology, history and importance of the electron-cloud effect (ECE). We briefly discuss the simulation techniques used to quantify the electron-cloud (EC) dynamics. Finally, we present in more detail an effective theory to describe the EC density build-up in terms of a few effective parameters. For further details, the reader is encouraged to refer to the proceedings of many prior workshops, either dedicated to EC or with significant EC contents, incl… more
Date: October 8, 2010
Creator: Furman, M. A.
Partner: UNT Libraries Government Documents Department
open access

Comparing Vacuum and Extreme Ultraviolet Radiation for Postionization of Laser Desorbed Neutrals from Bacterial Biofilms and Organic Fullerene

Description: Vacuum and extreme ultraviolet radiation from 8 - 24 eV generated at a synchrotron was used to postionize laser desorbed neutrals of antibiotic-treated biofilms and a modified fullerene using laser desorption postionization mass spectrometry (LDPI-MS). Results show detection of the parent ion, various fragments, and extracellular material from biofilms using LDPI-MS with both vacuum and extreme ultraviolet photons. Parent ions were observed for both cases, but extreme ultraviolet photons (16-24… more
Date: December 8, 2010
Creator: Gaspera, Gerald L.; Takahashi, Lynelle K.; Zhou, Jia; Ahmed, Musahid; Moored, Jerry F. & Hanley, Luke
Partner: UNT Libraries Government Documents Department
open access

CO2 Capture with Enzyme Synthetic Analogue

Description: Overview of an ongoing, 2 year research project partially funded by APRA-E to create a novel, synthetic analogue of carbonic anhydrase and incorporate it into a membrane for removal of CO2 from flue gas in coal power plants. Mechanism background, preliminary feasibility study results, molecular modeling of analogue-CO2 interaction, and program timeline are provided.
Date: November 8, 2010
Creator: Cordatos, Harry
Partner: UNT Libraries Government Documents Department
open access

Electronic and magnetic structure of GaxFe1-x thin films

Description: The electronic as well as magnetic properties of Ga{sub x}Fe{sub 1-x} films were studied by soft x-ray measurements. Using x-ray magnetic circular dichroism the Fe majority-spin band was found to be completely filled for x {approx} 0.3. With further enhanced Ga content, the Fe moment as well as the angular dependence of the x-ray magnetic linear dichroism decrease strongly, which we attribute to the formation of D0{sub 3} precipitates. Moreover, the magnetocrystalline anisotropy drops significa… more
Date: September 8, 2010
Creator: Arenholz, E.; van der Laan, G.; McClure, A. & Idzerda, Y.
Partner: UNT Libraries Government Documents Department
open access

An Improved Reaction Rate Equation for Simulating the Ignition and Growth of Reaction in High Explosives

Description: We describe an improved reaction rate equation for simulating ignition and growth of reaction in high explosives. It has been implemented into CALE and ALE3D as an alternate to the baseline the Lee-Tarver reactive flow model. The reactive flow model treats the explosive in two phases (unreacted/reactants and reacted/products) with a reaction rate equation to determine the fraction reacted, F. The improved rate equation has fewer parameters, is continuous with continuous derivative, results in a… more
Date: March 8, 2010
Creator: Murphy, M J
Partner: UNT Libraries Government Documents Department
open access

Controlled incorporation of mid-to-high Z transition metals in CVD diamond

Description: We report on a general method to fabricate transition metal related defects in diamond. Controlled incorporation of Mo and W in synthetic CVD diamond was achieved by adding volatile metal precursors to the diamond chemical vapor deposition (CVD) growth process. Effects of deposition temperature, grain structure and precursor exposure on the doping level were systematically studied, and doping levels of up to 0.25 at.% have been achieved. The metal atoms are uniformly distributed throughout the … more
Date: January 8, 2010
Creator: Biener, M M; Biener, J; Kucheyev, S O; Wang, Y M; El-Dasher, B; Teslich, N E et al.
Partner: UNT Libraries Government Documents Department
open access

Deflagration Rate Measurements of Three Insensitive High Explosives: LLM-105, TATB, and DAAF

Description: The pressure dependent deflagration rates of LLM-105, DAAF and TATB based formulations were measured in the LLNL high pressure strand burner. The role of binder amount, explosive type, and thermal damage and their effects on the deflagration rate will be discussed. One DAAF formulation, two different formulations of LLM-105, and four formulations of TATB were studied; results indicate that binder amount and type play a minor role in the deflagration behavior. This is in sharp contrast to the HM… more
Date: March 8, 2010
Creator: Glascoe, E A; Maienschein, J L; Lorenz, K T; Tan, N & Koerner, J G
Partner: UNT Libraries Government Documents Department
open access

Recent Advances in Automatic Alignment System for the National Iginition Facility

Description: The automatic alignment system for the National Ignition Facility (NIF) is a large-scale parallel system that directs all 192 laser beams along the 300-m optical path to a 50-micron focus at target chamber in less than 50 minutes. The system automatically commands 9,000 stepping motors to adjust mirrors and other optics based upon images acquired from high-resolution digital cameras viewing beams at various locations. Forty-five control loops per beamline request image processing services runni… more
Date: December 8, 2010
Creator: Wilhelmsen, K.; Awwal, A.; Kalantar, D.; Leach, R.; Lowe-Webb, R.; McGuigan, D. et al.
Partner: UNT Libraries Government Documents Department
open access

E-Cloud Effects on Singe-Bunch Dynamics in the Proposed PS2

Description: One of the options considered for future upgrades of the LHC injector complex entails the replacement of the PSwith the PS2, a longer circumference and higher energy synchrotron. Electron cloud effects represent an importantpotential limitation to the achievement of the upgrade goals. We report the results of numerical studies aimingat estimating the e-cloud density thresholds for the occurrence of single bunch instabilities.
Date: October 8, 2010
Creator: Venturini, M.; Furman, M. & Vay, J. L.
Partner: UNT Libraries Government Documents Department
open access

Improving the Material Response for Slow Heat of Energetic Materials

Description: The goal of modern high explosive slow heat cookoff modeling is to understand the level of mechanical violence. This requires understanding the coupled thermal-mechanical-chemical system that such an environment creates. Recent advances have improved our ability to predict the time to event, and we have been making progress on predicting the mechanical response. By adding surface tension to the product gas pores in the high explosive, we have been able to reduce the current model's tendency to … more
Date: March 8, 2010
Creator: Nichols, A. L.
Partner: UNT Libraries Government Documents Department
open access

Neutronics Design of a Thorium-Fueled Fission Blanket for LIFE (Laser Inertial Fusion-based Energy)

Description: The Laser Inertial Fusion-based Energy (LIFE) project at LLNL includes development of hybrid fusion-fission systems for energy generation. These hybrid LIFE engines use high-energy neutrons from laser-based inertial confinement fusion to drive a subcritical blanket of fission fuel that surrounds the fusion chamber. The fission blanket contains TRISO fuel particles packed into pebbles in a flowing bed geometry cooled by a molten salt (flibe). LIFE engines using a thorium fuel cycle provide poten… more
Date: March 8, 2010
Creator: Powers, J.; Abbott, R.; Fratoni, M.; Kramer, K.; Latkowski, J.; Seifried, J. et al.
Partner: UNT Libraries Government Documents Department
open access

RADBALL TECHNOLOGY TESTING IN THE SAVANNAH RIVER SITE HEALTH PHYSICS INSTRUMENT CALIBRATION LABORATORY

Description: The United Kingdom's National Nuclear Laboratory (NNL) has developed a radiation-mapping device that can locate and quantify radioactive hazards within contaminated areas of the nuclear industry. The device, known as RadBall{trademark}, consists of a colander-like outer collimator that houses a radiation-sensitive polymer sphere. The collimator has over two hundred small holes; thus, specific areas of the polymer sphere are exposed to radiation becoming increasingly more opaque in proportion to… more
Date: July 8, 2010
Creator: Farfan, E.
Partner: UNT Libraries Government Documents Department
open access

MCNPX Simulation Study of STRAW Neutron Detectors

Description: A novel prototype fission meter is being designed at National Security Technologies, LLC, using a thin uniform coating (only 1 micron thick) of {sup 10}B as a neutron converter inside a large array of thin (4 mm diameter) copper tubes. The copper tubes are only 2 mils thick, and each holds the stretched anode wire under tension and high voltage. The tubes are filled with proportional counter gas (a mixture of 90%/10% of Ar/CO{sub 2}). The tubes operate in proportional counter mode and attract m… more
Date: January 8, 2010
Creator: Sanjoy Mukhopadhyay, Richard Maurer, Stephen Mitchell
Partner: UNT Libraries Government Documents Department
open access

CERTS Microgrid Laboratory Test Bed

Description: The objective of the CERTS Microgrid Test Bed project was to enhance the ease of integrating energy sources into a microgrid. The project accomplished this objective by developing and demonstrating three advanced techniques, collectively referred to as the CERTS Microgrid concept, that significantly reduce the level of custom field engineering needed to operate microgrids consisting of generating sources less than 100kW. The techniques comprising the CERTS Microgrid concept are: 1 a method for … more
Date: June 8, 2010
Creator: ETO, J.; LASSETER, R.; SCHENKMAN, B.; STEVENS, J.; KLAPP, D.; VOLKOMMER, H. et al.
Partner: UNT Libraries Government Documents Department
open access

Evidence for plasma phase transition in high pressure hydrogen from ab-initio simulations

Description: We have performed a detailed study of molecular dissociation in liquid hydrogen using both Born-Oppenheimer molecular dynamics with Density Functional Theory and Coupled Electron-Ion Monte Carlo simulations. We observe a range of densities where (dP/d{rho}){sub T} = 0 that coincides with sharp discontinuities in the electronic conductivity, which is clear evidence of the plasma phase transition for temperatures 600K {le} T {le} 1500K. Both levels of theory exhibit the transition, although Quant… more
Date: February 8, 2010
Creator: Morales, M; Pierleoni, C; Schwegler, E & Ceperley, D
Partner: UNT Libraries Government Documents Department
open access

Radballtechnology Testing and MCNP Modeling of the Tungsten Collimator

Description: The United Kingdom's National Nuclear Laboratory (NNL) has developed a remote, non-electrical, radiation-mapping device known as RadBall{trademark}, which can locate and quantify radioactive hazards within contaminated areas of the nuclear industry. RadBall{trademark} consists of a colander-like outer shell that houses a radiation-sensitive polymer sphere. The outer shell works to collimate radiation sources and those areas of the polymer sphere that are exposed react, becoming increasingly mor… more
Date: July 8, 2010
Creator: Farfan, E.
Partner: UNT Libraries Government Documents Department
open access

Strain induced electronic structure changes in magnetic transition metal oxides thin films

Description: We show that the angular dependence of x-ray magnetic circular dichroism (XMCD) is strongly sensitive to strain-induced electronic structure changes in magnetic transition metal oxides. We observe a pronounced dependence of the XMCD spectral shape on the experimental geometry as well as nonvanishing XMCD with distinct spectral features in transverse geometry in compressively strained MnCr{sub 2}O{sub 4} films. The angular dependent XMCD can be described as a sum over an isotropic and anisotropi… more
Date: July 8, 2010
Creator: van der Laan, G.; Chopdekar, R.V.; Suzuki, Y. & Arenholz, E.
Partner: UNT Libraries Government Documents Department
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