States

Electric Boosting System for Light Truck/SUV Application (open access)

Electric Boosting System for Light Truck/SUV Application

Turbo diesel engine use in passenger cars in Europe has resulted in 30-50% improvement in fuel economy. Diesel engine application is particularly suitable for US because of vehicle size and duty cycle patterns. Adopting this technology for use in the US presents two issues--emissions and driveability. Emissions reduction technology is being well addressed with advanced turbocharging, fuel injection and catalytic aftertreatment systems. One way to address driveability is to eliminate turbo lag and increase low speed torque. Electrically assisted turbocharging concepts incorporated in e-TurboTM designs do both. The purpose of this project is to design and develop an electrically assisted turbocharger, e-TurboTM, for diesel engine use in the US. In this report, early design and development of electrical assist technology is described together with issues and potential benefits. In this early phase a mathematical model was developed and verified. The model was used in a sensitivity study. The results of the sensitivity study together with the design and test of first generation hardware was fed into second generation designs. In order to fully realize the benefits of electrical assist technology it was necessary to expand the scope of work to include technology on the compressor side as well as electronic …
Date: June 22, 2005
Creator: Steve Arnold, Craig Balis, Pierre Barthelet, Etienne Poix, Tariq Samad, Greg Hampson, S.M. Shahed
Object Type: Report
System: The UNT Digital Library
Dust-Plasma (open access)

Dust-Plasma

Our theoretical research on dust-plasma interactions has concentrated on three main areas: a)studies of grain charging and applications; b) waves and instabilities in weakly correlated dusty plasma with applications to space and laboratory plasmas; c) waves in strongly coupled dusty plasmas.
Date: February 22, 2005
Creator: Rosenberg, Marelene
Object Type: Report
System: The UNT Digital Library
Density distribution for a polymer adsorbed at an oil-water interface (open access)

Density distribution for a polymer adsorbed at an oil-water interface

None
Date: August 22, 2005
Creator: Cai, Jun & Prausnitz, John M.
Object Type: Article
System: The UNT Digital Library
Insulating Structural Ceramics Program, Final Report (open access)

Insulating Structural Ceramics Program, Final Report

New materials and corresponding manufacturing processes are likely candidates for diesel engine components as society and customers demand lower emission engines without sacrificing power and fuel efficiency. Strategies for improving thermal efficiency directly compete with methodologies for reducing emissions, and so the technical challenge becomes an optimization of controlling parameters to achieve both goals. Approaches being considered to increase overall thermal efficiency are to insulate certain diesel engine components in the combustion chamber, thereby increasing the brake mean effective pressure ratings (BMEP). Achieving higher BMEP rating by insulating the combustion chamber, in turn, requires advances in material technologies for engine components such as pistons, port liners, valves, and cylinder heads. A series of characterization tests were performed to establish the material properties of ceramic powder. Mechanical chacterizations were also obtained from the selected materials as a function of temperature utilizing ASTM standards: fast fracture strength, fatique resistance, corrosion resistance, thermal shock, and fracture toughness. All ceramic materials examined showed excellent wear properties and resistance to the corrosive diesel engine environments. The study concluded that the ceramics examined did not meet all of the cylinder head insert structural design requirements. Therefore we do not recommend at this time their use for …
Date: November 22, 2005
Creator: Andrews, Mark J.; Tandon, Raj; Ott, Eric; Hind, Abi Akar; Long, Mike; Jensen, Robert et al.
Object Type: Report
System: The UNT Digital Library
Plate-Based Fuel Processing System Final Report (open access)

Plate-Based Fuel Processing System Final Report

On-board reforming of liquid fuels into hydrogen is an enabling technology that could accelerate consumer usage of fuel cell powered vehicles. The technology would leverage the convenience of the existing gasoline fueling infrastructure while taking advantage of the fuel cell efficiency and low emissions. Commercial acceptance of on-board reforming faces several obstacles that include: (1) startup time, (2) transient response, and (3) system complexity (size, weight and cost). These obstacles are being addressed in a variety of projects through development, integration and optimization of existing fuel processing system designs. In this project, CESI investigated steam reforming (SR), water-gas-shift (WGS) and preferential oxidation (PrOx) catalysts while developing plate reactor designs and hardware where the catalytic function is integrated into a primary surface heat exchanger. The plate reactor approach has several advantages. The separation of the reforming and combustion streams permits the reforming reaction to be conducted at a higher pressure than the combustion reaction, thereby avoiding costly gas compression for combustion. The separation of the two streams also prevents the dilution of the reformate stream by the combustion air. The advantages of the plate reactor are not limited to steam reforming applications. In a WGS or PrOx reaction, the non-catalytic side …
Date: December 22, 2005
Creator: Faz, Carlos; Liu, Helen; Nicole, Jacques & Yee, David
Object Type: Report
System: The UNT Digital Library
Last Annotation of Fugu rubripes at JGI (open access)

Last Annotation of Fugu rubripes at JGI

None
Date: November 22, 2005
Creator: Salamov, Asaf; Terry, Astrid; Putnam, Nicholas; Rokhsar, Dan; Grigoriev, Igor; Eddie, Loh et al.
Object Type: Article
System: The UNT Digital Library
Physical and Electronic Properties Changed by Aging Plutonium (open access)

Physical and Electronic Properties Changed by Aging Plutonium

Plutonium, because of its radioactive nature, ages from the ''inside out'' by means of self-irradiation damage and thus produces Frankel-type defects and defect clusters. The defects resulting from the residual lattice damage and helium in-growth could result in microstructural, electronic, and physical property changes. This paper presents volume, density, and electronic property change observed from both naturally and accelerated aged plutonium alloys. Accelerated alloys are plutonium alloys with a fraction of Pu-238 to accelerate the aging process by approximately 18 times the rate of unaged weapons-grade plutonium. After thirty-five equivalent years of aging on accelerated alloys, the samples have swelled in volume by approximately 0.1% and now exhibit a near linear volume increase due to helium in-growth. We will correlate the physical property changes to the electronic structure of plutonium observed by the resonant photoelectron spectroscopy (RESPES).
Date: March 22, 2005
Creator: Chung, B. W.; Tobin, J. G.; Thompson, S. R. & Ebbinghaus, B. B.
Object Type: Article
System: The UNT Digital Library
Numerical Studies of Fluid Leakage from a Geologic DisposalReservoir for CO2 Show Self-Limiting Feedback between Fluid Flow and HeatTransfer (open access)

Numerical Studies of Fluid Leakage from a Geologic DisposalReservoir for CO2 Show Self-Limiting Feedback between Fluid Flow and HeatTransfer

Leakage of CO2 from a hypothetical geologic storage reservoir along an idealized fault zone has been simulated, including transitions between supercritical, liquid, and gaseous CO2. We find strong non-isothermal effects due to boiling and Joule-Thomson cooling of expanding CO2. Leakage fluxes are limited by limitations in conductive heat transfer to the fault zone. The interplay between multiphase flow and heat transfer effects produces non-monotonic leakage behavior.
Date: March 22, 2005
Creator: Pruess, Karsten
Object Type: Article
System: The UNT Digital Library
Lied Animal Shelter Animal Campus Renewable Energy Demonstration Project (open access)

Lied Animal Shelter Animal Campus Renewable Energy Demonstration Project

The Animal Shelter campus plan includes a new adoption center coupled with a dog adoption park, a wellness/veterinary technician education center, a show arena, and an addition to the existing shelter that will accommodate all animal control and sheltering for the Las Vegas Valley. The new facility will provide a sophisticated and innovative presentation of the animals to be adopted in an attempt to improve the public's perception of shelter animals. Additionally, the Regional Animal Campus will be a ''green building'', embodying a design intent on balancing environmental responsiveness, resource efficiency and cultural and community sensitivity. Designing an energy-efficient building helps reduce pollution from burning fossil fuels, reduce disturbance of natural habitats for the harvesting of resources and minimizes global warming. The project will be a leader in the use of renewable energy by relying on photovoltaic panels, wind turbines, and solar collectors to produce a portion of the project's energy needs The building will operate more efficiently in comparison to a typical shelter through the use of monitoring and specialized cooling/heating equipment. Windows bringing in natural daylight will reduce the center's demand for electricity.
Date: November 22, 2005
Creator: Spitzmesser, Randy
Object Type: Report
System: The UNT Digital Library
THE HIGH ENERGY GRIBOV: SOME RECOLLECTIONS. (open access)

THE HIGH ENERGY GRIBOV: SOME RECOLLECTIONS.

I describe through a few anecdotes, Gribov's work on the high energy limit of strong interactions.
Date: May 22, 2005
Creator: McLerran, L.
Object Type: Article
System: The UNT Digital Library
2004 SITE ENVIRONMENTAL REPORT (open access)

2004 SITE ENVIRONMENTAL REPORT

Each year, Brookhaven National Laboratory (BNL) prepares an annual Site Environmental Report (SER) in accordance with DOE Order 231.1A, Environment, Safety and Health Reporting of the U.S. Department of Energy (DOE). The SER is written to inform the public, regulators, Laboratory employees, and other stakeholders of BNL's environmental performance during the calendar year in review. The report summarizes BNL's environmental data; environmental management performance; compliance with applicable DOE, federal, state, and local regulations; and restoration and surveillance monitoring programs. BNL has prepared annual SERs since 1971 and has documented nearly all of its environmental history since the Laboratory's inception in 1947. The SER is intended to be a technical document. It is available in print and as a downloadable file on the BNL web page at http://www.bnl.gov/esd/SER.htm. A summary of the SER is also prepared each year to provide a general overview of the report, and is distributed with a CD version of the full report. The summary supports BNL's educational and community outreach program.
Date: August 22, 2005
Creator: Brookhaven National Laboratory
Object Type: Report
System: The UNT Digital Library
Field Demonstration of a Membrane Process to Separate Nitrogen from Natural Gas (open access)

Field Demonstration of a Membrane Process to Separate Nitrogen from Natural Gas

The original proposal described the construction and operation of a 1 MMscfd treatment system to be operated at a Butcher Energy gas field in Ohio. The gas produced at this field contained 17% nitrogen. During pre-commissioning of the project, a series of well tests showed that the amount of gas in the field was significantly smaller than expected and that the nitrogen content of the wells was very high (25 to 30%). After evaluating the revised cost of the project, Butcher Energy decided that the plant would not be economical and withdrew from the project. Since that time, Membrane Technology and Research, Inc. (MTR) has signed a marketing and sales partnership with ABB Lummus Global, a large multinational corporation. MTR will be working with the company's Randall Gas Technology Group, a supplier of equipment and processing technology to the natural gas industry. Randall's engineering group first found a new site for the project at a North Texas Exploration (NTE) gas processing plant. The plant produced about 1 MMscfd of gas containing 24% nitrogen. The membrane unit was built to bring this gas to 4% nitrogen for delivery to the pipeline. The membrane skid was built by ABB. NTE ordered the …
Date: December 22, 2005
Creator: Lokhandwala, Kaaeid
Object Type: Report
System: The UNT Digital Library
Physical Characterization of Solid-Liquid Slurries at High Weight Fractions Using Optical and Ultrasonic Methods (open access)

Physical Characterization of Solid-Liquid Slurries at High Weight Fractions Using Optical and Ultrasonic Methods

Remediation of highly radioactive waste is a major technical and programmatic challenge for the DOE. Rapid, on-line physical characterization of highly concentrated slurries is required for the safe and efficient remediation of 90 million gallons of high level radioactive waste (HLW), sodium bearing waste, and mixed waste. The research presented here, describes a collaborative effort between Pacific Northwest National Laboratory (PNNL) and the University of Washington (UW) to directly address the need for rapid on-line characterization of the physical properties of HLW slurries during all phases of the remediation process, from in-tank characterization of sediments to monitoring of the concentration, particle size, and degree of agglomeration and gelation of slurries during transport. Near-surface characterization of the slurry flow in the particle size range from nanometer to micrometer is examined using optical low coherence reflectometry. Volumetric characterization at depths in the slurry flow, up to several centimeters in the particle size range from the micrometer to millimeter, is realized by utilizing ultrasonic backscatter and diffuses fields. One of the strengths, the teaming up of significant talents in both experimental and theoretical optics and in ultrasonics, provides a synergistic approach to integrate these complimentary techniques. One of the benefits of this combined …
Date: December 22, 2005
Creator: Burgess, L. W.; Brodsky, A. M. & Panetta, P. D.
Object Type: Report
System: The UNT Digital Library
Updated Evaluations for Americium Isotopes (open access)

Updated Evaluations for Americium Isotopes

Here we describe evaluations for Am isotopes that will be included in the next release of ENDL. Current ENDL99 evaluations for these isotopes are quite outdated and almost entirely undocumented. Because Am is important for several DNT applications, and because quality evaluations are either readily available or easily calculated, the effort to update ENDL seems warranted. Results from good existing evaluations are adopted whenever possible. To this end we devote the next section of this report to a consideration of the availability of evaluations The quality of different evaluations as well as comparisons against experiments are also presented and used to motivate our choice of adopted data sets. Plans for modifying and improving adopted evaluations are also discussed. For {sup 240}Am there are no existing evaluations. To fill this gap, we are providing a new Am evaluation based on calculations with the statistical model reaction codes TALYS and EMPIRE. This evaluation is described below. The ENDF/B-VI formatted file containing this evaluation is given in the appendix.
Date: September 22, 2005
Creator: Brown, D. A. & Pruet, J.
Object Type: Report
System: The UNT Digital Library
Nanoscale Twinning and Martensitic Transformation in Shock-Deformed BCC Metals (open access)

Nanoscale Twinning and Martensitic Transformation in Shock-Deformed BCC Metals

Shock-induced twinning and martensitic transformation in BCC-based polycrystalline metals (Ta and U-6wt%Nb) have been observed and studied using transmission electron microscopy (TEM). The length-scale of domain thickness for both twin lamella and martensite phase is found to be smaller than 100 nm. While deformation twinning of {l_brace}112{r_brace}<111>-type is found in Ta when shock-deformed at 15 GPa, both twinning and martensitic transformation are found in Ta when shock-deformed at 45 GPa. Similar phenomena of nanoscale twinning and martensitic transformation are also found in U6Nb shock-deformed at 30 GPa. Since both deformation twinning and martensitic transformation occurred along the {l_brace}211{r_brace}{sub b} planes associated with high resolved shear stresses, it is suggested that both can be regarded as alternative paths for shear transformations to occur in shock-deformed BCC metals. Heterogeneous nucleation mechanisms for shock-induced twinning and martensitic transformation are proposed and discussed.
Date: March 22, 2005
Creator: Hsiung, L L
Object Type: Article
System: The UNT Digital Library
Review of Geophysical Techniques to Define the Spatial Distribution of Subsurface Properties or Contaminants (open access)

Review of Geophysical Techniques to Define the Spatial Distribution of Subsurface Properties or Contaminants

This is a letter report to Fluor Hanford, Inc. The purpose of this report is to summarize state-of-the-art, minimally intrusive geophysical techniques that can be used to clarify subsurface geology, structure, moisture, and chemical composition. The technology review focused on geophysical characterization techniques that provide two- or three-dimensional information about the spatial distribution of subsurface properties and/or contaminants.
Date: August 22, 2005
Creator: Murray, Christopher J.; Last, George V. & Truex, Michael J.
Object Type: Report
System: The UNT Digital Library
Effect of fluoride in NTS groundwaters on the aqueous speciation of U, Np, Pu, Am and Eu (open access)

Effect of fluoride in NTS groundwaters on the aqueous speciation of U, Np, Pu, Am and Eu

To address SNJV concerns that fluoride in Nevada Test site (NTS) groundwaters may impact radionuclide speciation and transport, NTS water quality databases were obtained and scanned for analyses with high fluoride concentrations (> 10 mg/L). The aqueous speciation of nine representative samples of these groundwaters with added trace amounts of uranium (U), neptunium (Np), plutonium (Pu), americium (Am) and europium (Eu) was then calculated with the computer code EQ3NR assuming a temperature of 25 C, using currently available thermodynamic data for these species. Under conditions where U(VI), Np(V), Pu(IV), Am(III) and Eu(III) dominate, F complexes are insignificant (<1 mole %) for U, Np, Pu and Am. Eu-F complexes may be significant in groundwaters that lack bicarbonate, possess pH values less than about 7 at ambient temperatures, or contain F in extremely high concentrations (e.g. > 50 mg/L). The objective is to evaluate the extent to which fluoride in NTS groundwaters complex U(VI), Np(V), Pu(IV), Am(III) and Eu(III). The approach used is to screen existing databases of groundwater chemistry at NTS for waters with high fluoride concentrations and calculate the extent to which fluoride complexes with the nuclides of interest in these waters.
Date: March 22, 2005
Creator: Bruton, C J & Nimz, G J
Object Type: Report
System: The UNT Digital Library
Analysis Summary of an Assembled Western U.S. Dataset (open access)

Analysis Summary of an Assembled Western U.S. Dataset

The dataset for this report is described in Walter et al. (2004) and consists primarily of Nevada Test Site (NTS) explosions, hole collapse and earthquakes. In addition, there were several earthquakes in California and Utah; earthquakes recorded near Cataract Creek, Arizona; mine blasts at two areas in Arizona; and two mine collapses in Wyoming. In the vicinity of NTS there were mainshock/aftershock sequences at Little Skull Mt, Scotty's Junction and Hector ere mine. All the events were shallow and distances ranged from about 0.1 degree to regional distances. All of the data for these events were carefully reviewed and analyzed. In the following sections of the report, we describe analysis procedures, problems with the data and results of analysis.
Date: March 22, 2005
Creator: Ryall, F
Object Type: Report
System: The UNT Digital Library
Strain Relaxation in Si{sub 1-x}Ge{sub x} Thin Films on Si(100) Substrates: Modeling and Comparisons with Experiments (open access)

Strain Relaxation in Si{sub 1-x}Ge{sub x} Thin Films on Si(100) Substrates: Modeling and Comparisons with Experiments

Strained semiconductor thin films grown epitaxially on semiconductor substrates of different composition, such as Si{sub 1-x}Ge{sub x}/Si, are becoming increasingly important in modern microelectronic technologies. In this paper, we report a hierarchical computational approach for analysis of dislocation formation, glide motion, multiplication, and annihilation in Si{sub 1-x}Ge{sub x} epitaxial thin films on Si substrates. Specifically, a condition is developed for determining the critical film thickness with respect to misfit dislocation generation as a function of overall film composition, film compositional grading, and (compliant) substrate thickness. In addition, the kinetics of strain relaxation in the epitaxial film during growth or thermal annealing (including post-implantation annealing) is analyzed using a properly parameterized dislocation mean-field theoretical model, which describes plastic deformation dynamics due to threading dislocation propagation. The theoretical results for Si{sub 1-x}Ge{sub x} epitaxial thin films grown on Si (100) substrates are compared with experimental measurements and are used to discuss film growth and thermal processing protocols toward optimizing the mechanical response of the epitaxial film.
Date: March 22, 2005
Creator: Kolluri, K; Zepeda-Ruiz, L A; Murthy, C S & Maroudas, D
Object Type: Article
System: The UNT Digital Library
ON OPTIMIZATION OF THE DISPERSIVE SECTION STRENGTH IN HGHG FREE ELECTRON LASER (open access)

ON OPTIMIZATION OF THE DISPERSIVE SECTION STRENGTH IN HGHG FREE ELECTRON LASER

In HGHG FEL the optimum strength of dispersive section is determined by the maximum bunching that beam obtains after interaction with seed laser. In this paper we present a simple semi-analytic expression of the required dispersive section strength for a wide range of laser power, intrinsic energy spread and harmonic number.
Date: March 22, 2005
Creator: STAFTAN, T. & YU, L. H.
Object Type: Article
System: The UNT Digital Library
Obtaining Identical Results on Varying Numbers of Processors In Domain Decomposed particle Monte Carlo Simulations (open access)

Obtaining Identical Results on Varying Numbers of Processors In Domain Decomposed particle Monte Carlo Simulations

Domain decomposed Monte Carlo codes, like other domain-decomposed codes, are difficult to debug. Domain decomposition is prone to error, and interactions between the domain decomposition code and the rest of the algorithm often produces subtle bugs. These bugs are particularly difficult to find in a Monte Carlo algorithm, in which the results have statistical noise. Variations in the results due to statistical noise can mask errors when comparing the results to other simulations or analytic results. If a code can get the same result on one domain as on many, debugging the whole code is easier. This reproducibility property is also desirable when comparing results done on different numbers of processors and domains. We describe how reproducibility, to machine precision, is obtained on different numbers of domains in an Implicit Monte Carlo photonics code.
Date: March 22, 2005
Creator: Gentile, N A; Kalos, M H & Brunner, T A
Object Type: Article
System: The UNT Digital Library
Coupled Climate Model Appraisal a Benchmark for Future Studies (open access)

Coupled Climate Model Appraisal a Benchmark for Future Studies

The Program for Climate Model Diagnosis and Intercomparison (PCMDI) has produced an extensive appraisal of simulations of present-day climate by eleven representative coupled ocean-atmosphere general circulation models (OAGCMs) which were developed during the period 1995-2002. Because projections of potential future global climate change are derived chiefly from OAGCMs, there is a continuing need to test the credibility of these predictions by evaluating model performance in simulating the historically observed climate. For example, such an evaluation is an integral part of the periodic assessments of climate change that are reported by the Intergovernmental Panel on Climate Change. The PCMDI appraisal thus provides a useful benchmark for future studies of this type. The appraisal mainly analyzed multi-decadal simulations of present-day climate by models that employed diverse representations of climate processes for atmosphere, ocean, sea ice, and land, as well as different techniques for coupling these components (see Table). The selected models were a subset of those entered in phase 2 of the Coupled Model Intercomparison Project (CMIP2, Covey et al. 2003). For these ''CMIP2+ models'', more atmospheric or oceanic variables were provided than the minimum requirements for participation in CMIP2. However, the appraisal only considered those climate variables that were supplied from …
Date: August 22, 2005
Creator: Phillips, T. J.; AchutaRao, K.; Bader, D.; Covey, C.; Doutriaux, C. M.; Fiorino, M. et al.
Object Type: Article
System: The UNT Digital Library
Atomistic Simulations of Grain Boundary Pinning in CuFe Alloys (open access)

Atomistic Simulations of Grain Boundary Pinning in CuFe Alloys

The authors apply a hybrid Monte Carlo-molecular dynamics code to the study of grain boundary motion upon annealing of pure Cu and Cu with low concentrations of Fe. The hybrid simulations account for segregation and precipitation of the low solubility Fe, together with curvature driven grain boundary motion. Grain boundaries in two different systems, a {Sigma}7+U-shaped half-loop grain and a nanocrystalline sample, were found to be pinned in the presence of Fe concentrations exceeding 3%.
Date: May 22, 2005
Creator: Zepeda-Ruiz, L A; Gilmer, G H; Sadigh, B; Caro, J A & Oppelstrup, T
Object Type: Article
System: The UNT Digital Library
Hard X-ray and Hot Electron Environment in Vacuum Hohlraums at NIF (open access)

Hard X-ray and Hot Electron Environment in Vacuum Hohlraums at NIF

Time resolved hard x-ray images (hv > 9 keV) and time integrated hard x-ray spectra (hv = 18-150 keV) from vacuum hohlraums irradiated with four 351 nm wavelength NIF laser beams are presented as a function of hohlraum size and laser power and duration. The hard x-ray images and spectra provide insight into the time evolution of the hohlraum plasma filling and the production of hot electrons. The fraction of laser energy detected as hot electrons (f{sub hot}) and a comparison to a filling model are presented.
Date: September 22, 2005
Creator: McDonald, J. W.; Suter, L. J.; Landen, O. L.; Foster, J. M.; Celeste, J. R.; Holder, J. P. et al.
Object Type: Article
System: The UNT Digital Library