The Advanced Petroleum-Based Fuels Program Evaluation of EC-Diesel and Diesel Particulate Filters in Southern California Vehicle Fleets (open access)

The Advanced Petroleum-Based Fuels Program Evaluation of EC-Diesel and Diesel Particulate Filters in Southern California Vehicle Fleets

The EC-Diesel and particulate filter combination greatly reduced the particulate matter, hydrocarbon, and carbon monoxide emissions of all vehicles tested in the program to date. Particulate matter reductions greater than 98% were achieved. For several vehicles tested, the PM and HC emissions were less than background levels. Based on preliminary statistical analysis, there is 95%+ confidence that EC-D and particulate filters reduced emissions from three different types of vehicles. A fuel consumption penalty was not detectable using the current test procedures and chassis dynamometer laboratory. Test vehicles equipped with the CRT and DPX particulate filters and fueled with EC-Diesel fuel have operated reliably during the program start-up period.
Date: April 10, 2000
Creator: unknown
Object Type: Article
System: The UNT Digital Library

Alternative Fuels Program Natural Gas Engine Research and Development

None
Date: April 10, 2000
Creator: unknown
Object Type: Presentation
System: The UNT Digital Library
Analysis of East Tank Farms Contamination Survey Frequency (open access)

Analysis of East Tank Farms Contamination Survey Frequency

This document provides the justification for the change in survey frequency in East Tank Farms occupied contamination areas from weekly to monthly. The Tank Farms Radiological Control Organization has performed radiological surveys of its Contamination Area (CA) Double Shell Tank (DST) farms in 200 East Area on a weekly basis for several years. The task package (DST-W012) controlling these routines designates specific components, at a minimum, that must be surveyed whenever the task is performed. This document documents the evaluation of these survey requirements and provides the recommendation and basis for moving DST tank farms in the 200 East Area from a weekly to monthly contamination survey. The contamination surveys for occupied contamination areas in West Tank Farms (WTF) were changed from a weekly frequency to a monthly frequency in 1997. Review of contamination survey data in WTF indicates a monthly interval remains satisfactory.
Date: April 10, 2000
Creator: ELDER, R.E.
Object Type: Report
System: The UNT Digital Library
Atmosphere recovery and regeneration in heat treating operations: NICE3 Project fact sheet (open access)

Atmosphere recovery and regeneration in heat treating operations: NICE3 Project fact sheet

This report is a fact sheet written for the NICE3 Program on a new atmosphere gas recovery system for furnaces used in heat treating operations. The National Industrial Competitiveness through Energy, Environment, and Economics program (NICE3) promotes energy efficiency, clean production, and economic competitiveness in industry.
Date: April 10, 2000
Creator: National Renewable Energy Laboratory (U.S.)
Object Type: Book
System: The UNT Digital Library
Beam-beam simulations for separated beams (open access)

Beam-beam simulations for separated beams

We present beam-beam simulation results from a strong-strong gaussian code for separated beams for the LHC and RHIC. The frequency spectrum produced by the beam-beam collisions is readily obtained and offers a good opportunity for experimental comparisons. Although our results for the emittance blowup are preliminary, we conclude that, for nominal parameter values, there is no significant difference between separated beams and center-on-center collisions.
Date: April 10, 2000
Creator: Furman, Miguel A.
Object Type: Article
System: The UNT Digital Library
Brazing and spot welding innovations for joining aluminum alloys: Inventions and Innovation Aluminum Project Fact Sheet (open access)

Brazing and spot welding innovations for joining aluminum alloys: Inventions and Innovation Aluminum Project Fact Sheet

Fact sheet written for the Inventions and Innovation Program about a new technology for brazing and spot welding.
Date: April 10, 2000
Creator: National Renewable Energy Laboratory (U.S.)
Object Type: Book
System: The UNT Digital Library
Clean production of coke from waste carbonaceous fines: Inventions and innovation steel project fact sheet (open access)

Clean production of coke from waste carbonaceous fines: Inventions and innovation steel project fact sheet

This report is a fact sheet written for the Inventions and Innovation Program about a new process for manufacturing metallurgical grade coke briquettes for the steel industry.
Date: April 10, 2000
Creator: National Renewable Energy Laboratory (U.S.)
Object Type: Book
System: The UNT Digital Library
Computing Farms (open access)

Computing Farms

High energy physics, nuclear physics, space sciences, and many other fields have large challenges in computing. In recent years, PCs have achieved performance comparable to the high-end UNIX workstations, at a small fraction of the price. The authors review the development and broad applications of commodity PCs as the solution to CPU needs, and look forward to the important and exciting future of large scale PC computing.
Date: April 10, 2000
Creator: Yeh, G.P.
Object Type: Article
System: The UNT Digital Library
Cosmic microwave background: Past, future, and present (open access)

Cosmic microwave background: Past, future, and present

Anisotropies in the Cosmic Microwave Background (CMB) carry an enormous amount of information about the early universe. The anisotropy spectrum depends sensitively on close to a dozen cosmological parameters, some of which have never been measured before. Experiments over the next decade will help us extract these parameters, teaching us not only about the early universe, but also about physics at unprecedented energies. One of the dangers now is that scientist are tempted to ignore the present data and rely too much on the future. This would be a shame, for hundreds of individuals have put in a great amount of time building state-of-the-art instruments, making painstaking observations at remote places on and off the globe. It seems unfair to ignore all the data that has been taken to date simply because there will be more and better data in the future. The author then makes the following claims: (1) the theory of CMB anisotropies is understood; (2) using this understanding, he is able to extract from future observations extremely accurate measurements of about ten cosmological parameters; (3) taken at face value, present data determines one of these parameters, the curvature of the universe; and (4) the present data is …
Date: April 10, 2000
Creator: Dodelson, S.
Object Type: Article
System: The UNT Digital Library
Detecting antipersonnel mines with a handheld parabolic reflector transmitter/multistatic receiver impulse gpr (open access)

Detecting antipersonnel mines with a handheld parabolic reflector transmitter/multistatic receiver impulse gpr

A novel handheld time-domain array GPR antipersonnel mine detection system using an offset paraboloidal reflector antenna is described. The reflector collimates rays from an ultra-wideband transmitting feed, directing the microwave impulse forward, in front of the antenna structure. As such, much of the ground reflected wave is directed further forward, away from the operator, the reflector, and the receiving antennas, and thereby reducing the major source of clutter. The wave transmitted into the ground that interacts with the target, generating significant backscatter returning toward the receiving antennas. These receiving antennas are configured in a 2 by 2 array to provide spatial focusing in both the along- and cross-track directions. This system has been built and tested at both Lawrence Livermore National Laboratory, and GeoCenters, Inc. In both cases, custom-built wideband antenna elements generate narrow pulse shapes, which allow for resolving small non-metallic targets buried at shallow depths. The LLNL's Micro-Power Impulse Radar (MIR) operates in the 1.5 to 5 GHz range a very narrow pulse shape. The Geo-Centers wideband TEMR antenna elements have higher power, though lower frequency range (850 to 1700 MHz), and generate less residual ringing in the time signal. Preliminary measured data from both systems indicate that …
Date: April 10, 2000
Creator: Rappaport, C.; Yang, B.; Azevedo, S.; Rosenbury, T.; Gough, J. & Dean, A.
Object Type: Article
System: The UNT Digital Library
Domain Green's Function Sampling in Diffusion Monte Carlo (open access)

Domain Green's Function Sampling in Diffusion Monte Carlo

We discuss the mathematical basis of sampling diffusive paths in Monte Carlo using Green's functions that are themselves built up stochastically from Green's functions in geometrical subdomains. The method of spheres is a special case. We show that other subdomains can be used as well, and may be more efficient for some applications. We include the basis for construction of such subdomain Green's functions for rectangular domains (in any number of dimensions) and cylindrical domains.
Date: April 10, 2000
Creator: Kalos, M.H.
Object Type: Report
System: The UNT Digital Library
Energy and environmental innovations for chemically-preserved wood wastes (open access)

Energy and environmental innovations for chemically-preserved wood wastes

This report is a fact sheet written for the Inventions and Innovation Program about a new method of disposing of chemically treated wood wastes.
Date: April 10, 2000
Creator: National Renewable Energy Laboratory (U.S.)
Object Type: Book
System: The UNT Digital Library

The Environmental Science and Health Effects Program

The goal of the Environmental Science and Health Effect Program is to conduct policy-relevant research that will help us understand atmospheric impacts and potential health effects that may be caused by the use of petroleum-based fuels and alternative transportation fuels from mobile sources.
Date: April 10, 2000
Creator: Gurevich, Michael; Lawson, Doug & Mauderly, Joe
Object Type: Presentation
System: The UNT Digital Library
Export Promotion: Federal Agencies' Activities and Resources in Fiscal Year 1999 (open access)

Export Promotion: Federal Agencies' Activities and Resources in Fiscal Year 1999

A letter report issued by the General Accounting Office with an abstract that begins "Pursuant to a congressional request, GAO provided information on U.S. government programs intended to help businesses promote their products and services in overseas markets, focusing on: (1) the federal agencies involved in promoting exports of U.S. goods and services and the export promotion activities they perform; (2) these agencies' total resources devoted to export promotion in fiscal year (FY) 1999; and (3) the agencies' overseas resources devoted to export promotion during this period."
Date: April 10, 2000
Creator: United States. General Accounting Office.
Object Type: Report
System: The UNT Digital Library
A fracture mechanics approach for estimating fatigue crack initiation in carbon and low-alloy steels in LWR coolant environments (open access)

A fracture mechanics approach for estimating fatigue crack initiation in carbon and low-alloy steels in LWR coolant environments

A fracture mechanics approach for elastic-plastic materials has been used to evaluate the effects of light water reactor (LWR) coolant environments on the fatigue lives of carbon and low-alloy steels. The fatigue life of such steel, defined as the number of cycles required to form an engineering-size crack, i.e., 3-mm deep, is considered to be composed of the growth of (a) microstructurally small cracks and (b) mechanically small cracks. The growth of the latter was characterized in terms of {Delta}J and crack growth rate (da/dN) data in air and LWR environments; in water, the growth rates from long crack tests had to be decreased to match the rates from fatigue S-N data. The growth of microstructurally small cracks was expressed by a modified Hobson relationship in air and by a slip dissolution/oxidation model in water. The crack length for transition from a microstructurally small crack to a mechanically small crack was based on studies on small crack growth. The estimated fatigue S-N curves show good agreement with the experimental data for these steels in air and water environments. At low strain amplitudes, the predicted lives in water can be significantly lower than the experimental values.
Date: April 10, 2000
Creator: Park, H. B. & Chopra, O. K.
Object Type: Article
System: The UNT Digital Library
Interim report task 3: immobilization process/equipment testing - task 3.4: non-destructive evaluation part 1 of 2 to Lawrence Livermore National Laboratory under contract b345772 (open access)

Interim report task 3: immobilization process/equipment testing - task 3.4: non-destructive evaluation part 1 of 2 to Lawrence Livermore National Laboratory under contract b345772

This report contains a summary of the results generated for Task 3.4: Non-destructive Evaluation (a subtask of Task 3: Immobilization Process/Equipment Testing). The aim of this task was to carry out X-ray diffraction (XRD) on selected samples from previous Task 1: Form Development work. These XRD results were to be compared to the results obtained using quantitative scanning electron microscopy.
Date: April 10, 2000
Creator: Stewart, M W A; R, Vance E; Day, R A & Lumpkin, G R
Object Type: Report
System: The UNT Digital Library
Investigation of Mixed Metal Sorbent / Catalysts for the Simultaneous Removal of Sulfur and Nitrogen Oxides (open access)

Investigation of Mixed Metal Sorbent / Catalysts for the Simultaneous Removal of Sulfur and Nitrogen Oxides

Simultaneous removal of SO{sub 2} and NO{sub x} using a regenerable solid sorbent will constitute an important improvement over the use of separate processes for the removal of these two pollutants from stack gases and possibly eliminate several shortcomings of the individual SO{sub 2} and NO{sub x} removal operations. The work done at PETC and the DOE-funded investigation of the investigators on the sulfation and regeneration of alumina-supported cerium oxide sorbents have shown that they can perform well at relatively high temperatures (823-900 K) as regenerable desulfurization sorbents. Survey of the recent literature shows that addition of copper oxide to ceria lowers the sulfation temperature of ceria down to 773 K, sulfated ceria-based sorbents can function as selective SCR catalysts even at elevated temperatures, SO{sub 2} can be directly reduced to sulfur by CO on CuO-ceria catalysts, and ceria-based catalysts may have a potential for selective catalytic reduction of NO{sub x} by methane. These observations indicate a possibility of developing a ceria-based sorbent/catalyst which can remove both SO{sub 2} and NO{sub x} from flue gases within a relatively wide temperature window, produce significant amounts of elemental sulfur during regeneration, and use methane for the selective catalytic reduction of NO{sub x}. …
Date: April 10, 2000
Creator: Akyurtlu, Ates & Akyurtlu, Jale F.
Object Type: Report
System: The UNT Digital Library
IRS Modernization: Business Practice, Performance Management, and Information Technology Challenges (open access)

IRS Modernization: Business Practice, Performance Management, and Information Technology Challenges

Testimony issued by the General Accounting Office with an abstract that begins "Pursuant to a congressional request, GAO discussed the Internal Revenue Service's (IRS) modernization efforts, focusing on the business practice, performance management, and information technology challenges IRS faces."
Date: April 10, 2000
Creator: United States. General Accounting Office.
Object Type: Text
System: The UNT Digital Library
Making nanostructured pyrotechnics in a beaker (open access)

Making nanostructured pyrotechnics in a beaker

Controlling composition at the nanometer scale is well known to alter material properties in sometimes highly desirable and dramatic ways. In the field of energetic materials component distributions, particle size, and morphology, effect both sensitivity and reactivity performance. To date nanostructured energetic materials are largely unknowns with the exception of nanometer-sized reactive powders now being produced at a number of laboratories. We have invented a new method of making nanostructured energetic materials, specifically explosives, propellants, and pyrotechnics, using sol-gel chemistry. The ease of this synthetic approach along with the inexpensive, stable, and benign nature of the metal precursors and solvents permit large-scale syntheses to be carried out. This approach can be accomplished using low cost processing methods. We will describe here, for the first time, this new synthetic route for producing metal-oxide-based pyrotechnics. The procedure employs the use of stable and inexpensive hydrated-metal inorganic salts and environmentally friendly solvents such as water and ethanol. The synthesis is straightforward and involves the dissolution the metal salt in a solvent followed by the addition of an epoxide, which induces gel formation in a timely manner. Experimental evidence suggests that the epoxide acts as an irreversible proton scavenger that induces the hydrated-metal species …
Date: April 10, 2000
Creator: Gash, A. E.; Simpson, R. L.; Tillotson, T. M.; Satcher, J. H. & Hrubesh, L. W.
Object Type: Article
System: The UNT Digital Library
Neutrino radiation at muon colliders and storage rings (open access)

Neutrino radiation at muon colliders and storage rings

Intense highly collimated neutrino beams, created from muon decays at high-energy muon colliders or storage rings, cause significant radiation problems even at very large distances from the machine. A recently developed weighted neutrino interaction generator permits detailed Monte Carlo simulations of the interactions of neutrinos and of their progeny with the MARS code. Special aspects of neutrino radiation dose evaluation are discussed. Dose distributions in a tissue-equivalent phantom are calculated when irradiated with 100 MeV to 10 TeV neutrino beams. Results are obtained for a bare phantom, one embedded in several shielding materials, and one located at various distances behind a shield. Neutrino radiation is investigated around muon storage rings serving as the basis for neutrino factories. The most challenging problem of off-site neutrino dose from muon colliders and storage rings is studied. The distance from the collider ring (up to 60 km) at which the expected dose rates equals prescribed annual dose limits is calculated for 0.5--4 TeV muon colliders and 30 and 50 GeV muon storage rings. Possible mitigation of neutrino radiation problems are discussed and investigated.
Date: April 10, 2000
Creator: Mokhov, N.V. & Van Ginneken, A.J.
Object Type: Article
System: The UNT Digital Library
A New Class of High Force, Low-Voltage, Compliant Actuation System (open access)

A New Class of High Force, Low-Voltage, Compliant Actuation System

Although many actuators employing electrostatic comb drives have been demonstrated in a laboratory environment, widespread acceptance in mass produced microelectromechanical systems (MEMS) may be limited due to issues associated with low drive force, large real estate demands, high operating voltages, and reliability concerns due to stiction. On the other hand, comb drives require very low drive currents, offer predictable response, and are highly compatible with the fabrication technology. The expand the application space and facilitate the widespread deployment of self-actuated MEMS, a new class of advanced actuation systems has been developed that maintains the highly desirable aspects of existing components, while significantly diminishing the issues that could impede large scale acceptance. In this paper, the authors will present low-voltage electrostatic actuators that offer a dramatic increase in force over conventional comb drive designs. In addition, these actuators consume only a small fraction of the chip area previously used, yielding significant gains in power density. To increase the stroke length of these novel electrostatic actuators, the authors have developed highly efficient compliant stroke amplifiers. The coupling of compact, high-force actuators with fully compliant displacement multipliers sets a new paradigm for highly integrated microelectromechanical systems.
Date: April 10, 2000
Creator: Rodgers, M. Steven; Kota, Sridhar; Hetrick, Joel; Li, Zhe; Jensen, Brian D.; Krygowski, Thomas W. et al.
Object Type: Article
System: The UNT Digital Library
P-type doping of GaN (open access)

P-type doping of GaN

After implantation of As, As + Be, and As + Ga into GaN and annealing for short durations at temperatures as high as 1500 C, the GaN films remained highly resistive. It was apparent from c-RBS studies that although implantation damage did not create an amorphous layer in the GaN film, annealing at 1500 C did not provide enough energy to completely recover the radiation damage. Disorder recovered significantly after annealing at temperatures up to 1500 C, but not completely. From SIMS analysis, oxygen contamination in the AIN capping layer causes oxygen diffusion into the GaN film above 1400 C. The sapphire substrate (A1203) also decomposed and oxygen penetrated into the backside of the GaN layer above 1400 C. To prevent donor-like oxygen impurities from the capping layer and the substrate from contaminating the GaN film and compensating acceptors, post-implantation annealing should be done at temperatures below 1500 C. Oxygen in the cap could be reduced by growing the AIN cap on the GaN layer after the GaN growth run or by depositing the AIN layer in a ultra high vacuum (UHV) system post-growth to minimize residual oxygen and water contamination. With longer annealing times at 1400 C or at …
Date: April 10, 2000
Creator: Wong, R.K.
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Particulate briquetting technology for the steel industry: NICE3 (open access)

Particulate briquetting technology for the steel industry: NICE3

This report is a fact sheet on a new method for producing metallurgical furnace briquettes for the steel industry written for the NICE3 Program.
Date: April 10, 2000
Creator: National Renewable Energy Laboratory (U.S.)
Object Type: Book
System: The UNT Digital Library
Physics Design Considerations for Diagnostic X Electron Beam Transport System (open access)

Physics Design Considerations for Diagnostic X Electron Beam Transport System

The Diagnostic X (D-X) beamlines will transport the DARHT-II beam from the end of the accelerator to the Diagnostic X firing point providing four lines of sight for x-ray radiography. The design goal for the Diagnostic X beamline is to deliver four x-ray pulses with the DARHT-II dose format and time integrated spot size on each line of sight. The D-X beamline's final focus should be compatible with a range of first conjugates from 1 m-5 m. Furthermore, the D-X beamline operational parameters and the beamline layout should not preclude a possible upgrade to additional lines of sight. The DARHT-II accelerator is designed to deliver beams at a rate of 1 pulse per minute or less. Tuning the D-X beamline with several hundred optical elements would be time consuming. Therefore, minimizing the required number of tuning shots for the D-X beamline is also an important design goal. Many different beamline configurations may be able to accomplish these design objectives, and high beam quality (i.e., high current and low emittance) must be maintained throughout the chosen beamline configuration in order to achieve the DARHT-II x-ray dose format. In general, the longer the distance a beam travels, the harder it is to …
Date: April 10, 2000
Creator: Chen, Y. J.
Object Type: Report
System: The UNT Digital Library