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Electronic properties of the graphene/6H-SiC(0001̅ ) interface: A first-principles study (open access)

Electronic properties of the graphene/6H-SiC(0001̅ ) interface: A first-principles study

This article discusses electronic properties of the graphene/6H-SiC(0001̅) interface.
Date: July 27, 2011
Creator: Jayasekera, Thushari; Xu, Shu; Kim, Ki Wook & Buongiorno Nardelli, Marco
System: The UNT Digital Library
Linear Free Energy Relationship Correlation of the Distribution of Solutes between Water and Sodium Dodecyl Sulfate (SDS) Micelles and between Gas and SDS Micelles (open access)

Linear Free Energy Relationship Correlation of the Distribution of Solutes between Water and Sodium Dodecyl Sulfate (SDS) Micelles and between Gas and SDS Micelles

This article discusses linear free energy relationship correlation of the distribution of solutes between water and sodium dodecyl sulfate (SDS) micelles and between gas and SDS micelles.
Date: July 27, 2007
Creator: Sprunger, Laura M.; Acree, William E. (William Eugene) & Abraham, M. H. (Michael H.)
System: The UNT Digital Library
Phase Equilibria in High Energy Density PVDF-Based Polymers (open access)

Phase Equilibria in High Energy Density PVDF-Based Polymers

Article on phase equilibria in high energy density PVDF-based polymers.
Date: July 27, 2007
Creator: Ranjan, Vivek; Yu, Liping; Buongiorno Nardelli, Marco & Bernholc, Jerry
System: The UNT Digital Library
Switchgrass (Panicum virgatum) possesses a divergent family of cinnamoyl CoA reductases with distinct biochemical properties (open access)

Switchgrass (Panicum virgatum) possesses a divergent family of cinnamoyl CoA reductases with distinct biochemical properties

Article on switchgrass (Panicum virgatum) possessing a divergent family of cinnamoyl CoA reductases with distinct biochemical properties.
Date: July 27, 2009
Creator: Escamilla-Treviño, Luis; Shen, Hui; Uppalapati, Srinivasa Rao; Ray, Tui; Tang, Yuhong; Hernandez, Timothy et al.
System: The UNT Digital Library
Kinetic studies of the Cl + HI reaction using three techniques (open access)

Kinetic studies of the Cl + HI reaction using three techniques

Article on kinetic studies of the Cl + HI reaction using three techniques.
Date: July 27, 2004
Creator: Yuan, Jessie; Misra, Ashutosh; Goumri, Abdellatif; Shao, Diane D. & Marshall, Paul
System: The UNT Digital Library
Adaptive optics high resolution spectroscopy: present status and future direction (open access)

Adaptive optics high resolution spectroscopy: present status and future direction

High resolution spectroscopy experiments with visible adaptive optics (AO) telescopes at Starfire Optical Range and Mt. Wilson have demonstrated that spectral resolution can be routinely improved by a factor of - 10 over the seeing-limited case with no extra light losses at visible wavelengths. With large CCDs now available, a very wide wavelength range can be covered in a single exposure. In the near future, most large ground-based telescopes will be equipped with powerful A0 systems. Most of these systems are aimed primarily at diffraction-limited operation in the near IR. An exciting new opportunity will thus open up for high resolution IR spectroscopy. Immersion echelle gratings with much coarser grooves being developed by us at LLNL will play a critical role in achieving high spectral resolution with a compact and low cost IR cryogenically cooled spectrograph and simultaneous large wavelength coverage on relatively small IR detectors. We have constructed a new A0 optimized spectrograph at Steward Observatory to provide R = 200,000 in the optical, which is being commissioned at the Starfire Optical Range 3.5m telescope. We have completed the optical design of the LLNL IR Immersion Spectrograph (LISPEC) to take advantage of improved silicon etching technology. Key words: adaptive …
Date: July 27, 1999
Creator: Alcock, C.; Angel, R.; Ciarlo, D.; Fugate, R. O.; Ge, J.; Kuzmenko, P. et al.
System: The UNT Digital Library
GIS Meets Airborne MSS: Geospatial Applications of High-Resolution Multispectral Data (open access)

GIS Meets Airborne MSS: Geospatial Applications of High-Resolution Multispectral Data

Bechtel Nevada operates and flies Daedalus multispectral scanners for funded project tasks at the Department of Energy's Remote Sensing Laboratory. Historically, processing and analysis of multispectral data has afforded scientists the opportunity to see natural phenomena not visible to the naked eye. However, only recently has a system, more specifically a Geometric Correction System, existed to automatically geo-reference these data directly into a Geographic Information (GIS) database. Now, analyses, performed previously in a nongeospatial environment, are integrated directly into an Arc/Info GIS. This technology is of direct benefit to environmental and emergency response applications.
Date: July 27, 1999
Creator: Guber, Albert
System: The UNT Digital Library
Nuclear material estimation and uncertainties for the spent fuel treatment at FCF. (open access)

Nuclear material estimation and uncertainties for the spent fuel treatment at FCF.

Spent fuel from the Experimental Breeder Reactor-II (EBR-II) is treated at the Fuel Conditioning Facility (FCF) located at Argonne National Laboratory-West (ANL-W). A number of sensitive nuclear material streams are present in the facility, which mainly include material in the input spent fuel, the element chopper, the electrorefiner, the cathode processor, and the casting furnace. Different types of measurements and calculations are performed in order to estimate the amount of material in those streams. There are three basic types of measurements: weight, elemental and isotopic fractions, and liquid level measurements. Materials in some streams are determined using validated models, which include the mass and composition of the input spent fuel. This paper describes the different streams of sensitive nuclear material for the facility, and the methods for their measurements or estimation as part of the MC&A system at FCF. It also describes the analytical and sampling uncertainties associated with those measurements and estimates, which are required for the facility variance propagation calculations.
Date: July 27, 1999
Creator: Battisti, T.; Bucher, R. G.; Krsul, J.; Mariani, R. D.; McKnight, R. D.; Vaden, D. et al.
System: The UNT Digital Library
U.S. Transparency monitoring under the U.S./Russian HEU purchase agreement (open access)

U.S. Transparency monitoring under the U.S./Russian HEU purchase agreement

The conversion of Highly Enriched Uranium (HEU) metal to low enriched uranium (LEU) takes place at four Russian sites. HEU metal to oxide processing began in 1994 with shipments of HEU oxide from the Siberian Chemical Enterprise (SChE) to the Ural Electrochemical Integrated Plant (UEIP) fluorination and blending facility. U.S. transparency monitoring at these facilities began in February 1996. In 1996, fluorination and blending operations began at the Electrochemical Plant (ECP). In 1997, additional HEU metal to oxide was added at the Mayak Production Association (MPA), and additional fluorination and blending operations have been performed at SChE. U.S. transparency monitoring at these facilities is intended to provide confidence that HEU weapons components are received, that the HEU metal is converted to HEU oxide, and that the HEU is blended to LEU prior to shipment to the U.S. Enrichment Corporation (USEC). The monitoring begins with observation of HEU weapon components in sealed containers, including confirmation of the {sup 235}U enrichment using U.S. nondestructive assay (NDA) equipment. The feeding of HEU metal shavings to the oxidation process and the subsequent packaging of the HEU oxide for shipment to the fluorination and blending facilities are then monitored. At those facilities, monitors are allowed …
Date: July 27, 1999
Creator: Benton, J.; Dougherth, D. R.; Glaser, J. W. & Thomas, D. C.
System: The UNT Digital Library
U.S. DOE's Emergency Communications Network Site Atlas Project (open access)

U.S. DOE's Emergency Communications Network Site Atlas Project

Bechtel Nevada supports the US Department of Energy's Emergency Operations Center by providing Geographic Information System support in the areas of database maintenance, user interface, and daily emergency preparedness operations. This support includes preparation of a set of standardized atlases for many of the sites run by the Department of Energy. The atlases are created from one suite of ARC Macro Language programs that handles problems with producing consistent output for many maps in many different scales from data obtained from multiple sources and created at various scales. Flexibility and ease of change/update are the key benefits of this system.
Date: July 27, 1999
Creator: Coffey, J.R.
System: The UNT Digital Library
Renewable Energy Technologies for Designing and Constructing Low-Energy Commercial Buildings (open access)

Renewable Energy Technologies for Designing and Constructing Low-Energy Commercial Buildings

The Thermal Test Facility (TTF) at the National Renewable Energy Laboratory (NREL) in Golden, Colorado, was designed and constructed using a whole-building energy design approach. This approach treats a building as a single unit, not as a shell containing many separate systems. It relies on the use of energy simulation tools for optimization throughout the design process, and requires the involvement and commitment of the architect, engineer, and owner. It can produce a building that requires substantially less energy than a building designed and constructed with conventional means. TTF operating costs are 63% less than those of a code-compliant basecase building. These savings were achieved by implementing an approach that optimized passive solar technologies and integrated energy-efficient building systems. Passive solar technologies include daylighting, high-efficiency lighting systems, engineered overhangs, direct solar gains for heating, thermal mass building materials, managed glazing, and a good thermal envelope. The energy-efficient heating, ventilating, and air-conditioning (HVAC) system, designed to work with the building's passive solar technologies, includes ventilation air preheat, ceiling fans, indirect/direct evaporative cooling, and an automatic control system. This paper focuses on the design features of the TTF and the results of tests conducted on the TTF since its completion in 1996. …
Date: July 27, 1998
Creator: Torcellini, P. A.; Hayter, S. J.; Ketcham, M. S.; Judkoff, R. & Jenior, M. M.
System: The UNT Digital Library
Improving Regional Seismic Event Location Through Calibration of the International Monitoring System (open access)

Improving Regional Seismic Event Location Through Calibration of the International Monitoring System

At Lawrence Livermore National Laboratory (LLNL), we are working to help calibrate the 170 seismic stations that are part of the Comprehensive Nuclear-Test-Ban Treaty (CTBT) monitoring network, in order to enhance the network's ability to locate small seismic events. These low magnitude events are likely to be recorded by only the closest of seismic stations, ranging from local to near teleseismic distances. At these distance ranges, calibration statistics become highly nonstationary, challenging us to develop more general statistical models for proper calibration. To meet the goals outlined above, we are developing a general nonstationary framework to accurately calibrate seismic travel-time predictions over the full distance range, from local, to regional, to teleseismic distances. The objective of this framework is to develop valid region-specific corrections for the Middle Fast, North Africa, and portions of the Soviet Union, to assess our progress towards meeting calibration goals, and to perform cost-benefit analysis for future calibrations. The framework integrates six core components essential to accurate calibration. First, is the compilation and statistical characterization of well located reference events, including aftershock sequences, mining explosions and rockbursts, calibration explosions, and teleseismically constrained events (Harris et al., SSA 1999; Hanley et al., SSA 1999). Second, is the …
Date: July 27, 1999
Creator: Schultz, Craig A.; Myers, Stephen C.; Flanagan, Megan; Swenson, Jennifer; Hanley, William & Pasyanos, Micheal
System: The UNT Digital Library
3(omega) damage threshold evaluation of final optics components using Beamlet mule and off-line testing (open access)

3(omega) damage threshold evaluation of final optics components using Beamlet mule and off-line testing

A statistics-based model is being developed to predict the laser-damage-limited lifetime of UV optical components on the NIF laser. In order to provide data for the model, laser damage experiments were performed on the Beamlet laser system at LLNL. An early prototype NIF focus lens was exposed to twenty 35 1 nm pulses at an average fluence of 5 J/cm{sup 2}, 3ns. Using a high resolution optic inspection system a total of 353 damage sites was detected within the 1160 cm{sup 2} beam aperture. Through inspections of the lens before, after and, in some cases, during the campaign, pulse to pulse damage growth rates were measured for damage initiating both on the surface and at bulk inclusions. Growth rates as high as 79 {micro}m/pulse (surface diameter) were observed for damage initiating at pre-existing scratches in the surface. For most damage sites on the optic, both surface and bulk, the damage growth rate was approximately l0{micro}m/pulse. The lens was also used in Beamlet for a subsequent 1053 {micro}m/526 {micro}m campaign. The 352 {micro}m-initiated damage continued to grow during that campaign although at generally lower growth rate.
Date: July 27, 1998
Creator: Kozlowski, M. F.; Maricle, S.; Mouser, R.; Schwartz, S.; Wegner, P. & Weiland, T.
System: The UNT Digital Library
Vendor-based laser damage metrology equipment supporting the National Ignition Facility (open access)

Vendor-based laser damage metrology equipment supporting the National Ignition Facility

A sizable laser damage metrology effort is required as part of optics production and installation for the 192 beam National Ignition Facility (NIF) laser. The large quantities, high damage thresholds, and large apertures of polished and coated optics necessitates vendor-based metrology equipment to assure component quality during production. This equipment must be optimized to provide the required information as rapidly as possible with limited operator experience. The damage metrology tools include: (1) platinum inclusion damage test systems for laser amplifier slabs, (2) laser conditioning stations for mirrors and polarizers, and (3) mapping and damage testing stations for UV transmissive optics. Each system includes a commercial Nd:YAG laser, a translation stage for the optics, and diagnostics to evaluate damage. The scanning parameters, optical layout, and diagnostics vary with the test fluences required and the damage morphologies expected. This paper describes the technical objectives and milestones involved in fulfilling these metrology requirements.
Date: July 27, 1998
Creator: Campbell, J. H; Jennings, R. T.; Kimmons, J. F.; Kozlowski, M. R.; Mouser, R. P.; Schwatz, S. et al.
System: The UNT Digital Library
Adsorption air conditioner for electric vehicle applications. Revision 1 (open access)

Adsorption air conditioner for electric vehicle applications. Revision 1

This paper shows an analysis of the applicability of an adsorption system for electric vehicle (EV) air conditioning. Adsorption systems are designed and optimized to provide the required cooling for four combinations of vehicle characteristics and driving cycles. The resulting adsorption systems are compared with vapor compression air conditioners that can satisfy the cooling load. The objective function is the overall system weight, which includes the cooling system weight and the weight of the battery necessary to provide energy for air conditioner operation. The system with the minimum overall weight is considered to be the best, because a lower weight results in an increased vehicle range. The results indicate that, for the conditions analyzed in this paper, vapor compression air conditioners are superior to adsorption systems not only because they are lighter, but also because they have a higher COP and are more compact.
Date: July 27, 1994
Creator: Aceves, S.M.
System: The UNT Digital Library
Use of alternating-Z doubling in high-dynamic-range tripling: design and evaluation of an optimized prototype tripler (open access)

Use of alternating-Z doubling in high-dynamic-range tripling: design and evaluation of an optimized prototype tripler

We designed and tested an alternating-Z tripler that consisted of two detuned, Type-1, potassium dihydrogen phosphate (KD*P) doublers and one KD*P mixer. The crystal thicknesses were, respectively, 13, 10 and 10 mm, and the detunings of the doublers were +420 and -520 µrad. All three crystals were fabricated from 80% deuterated KDP. Conversion efficiency was measured and calculated for input 1053- nm pulses with approximately rectangular waveforms and durations of either 1 or 6 ns, and for 20-ns pulses that exhibited intensity variation by a factor of 10. The measured peak conversion efficiency was more than 80%, and energy conversion efficiencies ranged from 62-80% depending on the waveform of the input pulse. The expected large dynamic range in input intensity, 9-10, was observed, and the measured and calculated efficiencies were in excellent agreement.
Date: July 27, 1998
Creator: Auerbach, J. M.; Barker, C.; Eimerl, D.; Milan, D. & Milonni, P. W.
System: The UNT Digital Library
U.S. transparency monitoring of HEU oxide conversion and blending to LEU hexafluoride at three Russian blending plants (open access)

U.S. transparency monitoring of HEU oxide conversion and blending to LEU hexafluoride at three Russian blending plants

The down-blending of Russian highly enriched uranium (HEU) takes place at three Russian gaseous centrifuge enrichment plants. The fluorination of HEU oxide and down-blending of HEU hexafluoride began in 1994, and shipments of low enriched uranium (LEU) hexafluoride product to the United States Enrichment Corporation (USEC) began in 1995 US transparency monitoring under the HEU Purchase Agreement began in 1996 and includes a permanent monitoring presence US transparency monitoring at these facilities is intended to provide confidence that HEU is received and down-blended to LEU for shipment to USEC The monitoring begins with observation of the receipt of HEU oxide shipments, including confirmation of enrichment using US nondestructive assay equipment The feeding of HEU oxide to the fluorination process and the withdrawal of HEU hexafluoride are monitored Monitoring is also conducted where the blending takes place and where shipping cylinders are filled with LEU product. A series of process and material accountancy documents are provided to US monitors.
Date: July 27, 1998
Creator: Leich, D.
System: The UNT Digital Library
Recent B-physics results at CDF (open access)

Recent B-physics results at CDF

Between 1992 and 1996 CDF collected about 100 pb{sup {minus}1} of data at a {radical}s = 1.8 TeV at the Fermilab Tevatron collider. This data sample led to a large number of precision measurements of B hadrons properties including their masses, lifetimes and neutral B meson oscillation parameters and the discovery of the B{sub c} meson. Here the author reports on three recent results: the measurement of the B{sup +} production cross section, the search for radiative penguin B hadron decays and the measurement of the CP violating parameter sin 2{beta}. These results are significant examples of the breadth of the CDF program. In 2001 the main injector will allow the Tevatron initially to deliver 1 fb{sup {minus}1} per year at {radical}s = 2 TeV. The CDF detector will undergo major upgrades which will further increase the B physics reach.
Date: July 27, 2000
Creator: Bortoletto, Daniela
System: The UNT Digital Library
Preliminary designs for an IR insertion at C-Zero (open access)

Preliminary designs for an IR insertion at C-Zero

Given the advanced state of operational plans for late Run II (132 nsec bunch spacing) the C0 IR insert should be designed to operate such that it does not impact nominal Tevatron parameters. This implies an entirely localized insert -- one which is completely transparent to the rest of the machine. This condition has several important design implications, some of which are pointed out below. An IR design similar to that employed at CDF and D0 is unacceptable as a C0 candidate. The addition of such a (single) low-{beta} region to the machine raises the tune by a half-integer in each plane, moving them far from the standard operating point and right onto the 21.0 integer resonance. The nominal (fractional) operating point is most elegantly maintained by adding 2 local low-{beta} in each plane, thereby boosting the tunes by a full integer. The B0 and D0 IR's are not optically-isolated entities. Progression through the low-{beta}squeeze involves adjusting, not only the main IR quadrupoles, but also the tune quad strings distributed around the ring. The result is that the nominal lattice functions at any point in the ring, and the phase advances across any section of the ring, are not fixed, …
Date: July 27, 2000
Creator: Johnstone, John A.
System: The UNT Digital Library
Radiation in an Emitting and Absorbing Medium: A Gridless Approach (open access)

Radiation in an Emitting and Absorbing Medium: A Gridless Approach

A gridless technique for the solution of the integral form of the radiative heat flux equation for emitting and absorbing media is presented. Treatment of non-uniform absorptivity and gray boundaries is included. As part of this work, the authors have developed fast multipole techniques for extracting radiative heat flux quantities from the temperature fields of one-dimensional and three-dimensional geometries. Example calculations include those for one-dimensional radiative heat transfer through multiple flame sheets, a three-dimensional enclosure with black walls, and an axisymmetric enclosure with black walls.
Date: July 27, 2000
Creator: GRITZO,LOUIS A.; STRICKLAND,JAMES H. & DESJARDIN,PAUL E.
System: The UNT Digital Library
Design of a TRU Waste Repackaging System (open access)

Design of a TRU Waste Repackaging System

This paper addresses the work that SRTC is performing in the design, fabrication, assembly, and testing of the TRU-Waste Repackaging Module.
Date: July 27, 2000
Creator: Fogle, R. F.
System: The UNT Digital Library
Operation of the Bayes Inference Engine (open access)

Operation of the Bayes Inference Engine

The authors have developed a computer application, called the Bayes Inference Engine, to enable one to make inferences about models of a physical object from radiographs taken of it. In the BIE calculational models are represented by a data-flow diagram that can be manipulated by the analyst in a graphical-programming environment. The authors demonstrate the operation of the BIE in terms of examples of two-dimensional tomographic reconstruction including uncertainty estimation.
Date: July 27, 1998
Creator: Hanson, K. M. & Cunningham, G. S.
System: The UNT Digital Library
Fatigue Damage Accumulation in 63Sn-37Pb Solder Alloy (open access)

Fatigue Damage Accumulation in 63Sn-37Pb Solder Alloy

None
Date: July 27, 2000
Creator: WEI,Y.; CHOW,C.L.; NEILSEN,MICHAEL K. & FANG,HUEI ELIOT
System: The UNT Digital Library
Damage Mechanics Based Fatigue Life Prediction for 63Sn-37Pb Solder Materials (open access)

Damage Mechanics Based Fatigue Life Prediction for 63Sn-37Pb Solder Materials

None
Date: July 27, 2000
Creator: WEI,Y.; CHOW,C.L.; NEILSEN,MICHAEL K. & FANG,HUEI ELIOT
System: The UNT Digital Library