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Operation of a Four-Cylinder 1.9L Propane Fueled Homogeneous Charge Compression Ignition Engine: Basic Operating Characteristics and Cylinder-to-Cylinder Effects (open access)

Operation of a Four-Cylinder 1.9L Propane Fueled Homogeneous Charge Compression Ignition Engine: Basic Operating Characteristics and Cylinder-to-Cylinder Effects

A four-cylinder 1.9 Volkswagen TDI Engine has been converted to run in Homogeneous Charge Compression Ignition (HCCI) mode. The stock configuration is a turbocharged direct injection Diesel engine. The combustion chamber has been modified by discarding the in-cylinder Diesel fuel injectors and replacing them with blank inserts (which contain pressure transducers). The stock pistons contain a reentrant bowl and have been retained for the tests reported here. The intake and exhaust manifolds have also been retained, but the turbocharger has been removed. A heater has been installed upstream of the intake manifold and fuel is added just downstream of this heater. The performance of this engine in naturally aspirated HCCI operation, subject to variable intake temperature and fuel flow rate, has been studied. The engine has been run with propane fuel at a constant speed of 1800 rpm. This work is intended to characterize the HCCI operation of the engine in this configuration that has been minimally modified from the base Diesel engine. The performance (BMEP, IMEP, efficiency, etc) and emissions (THC, CO, NOx) of the engine are presented, as are combustion process results based on heat release analysis of the pressure traces from each cylinder.
Date: March 12, 2001
Creator: Flowers, D.; Aceves, S. M.; Martinez-Frias, J.; Smith, J. R.; Au, M.; Girard, J. et al.
Object Type: Article
System: The UNT Digital Library
Material Balance Assessment for Double-Shell Tank Waste Pipeline Transfer (open access)

Material Balance Assessment for Double-Shell Tank Waste Pipeline Transfer

PNNL developed a material balance assessment methodology based on conservation of mass for detecting leaks and mis-routings in pipeline transfer of double-shell tank waste at Hanford. The main factors causing uncertainty in these transfers are variable property and tank conditions of density, existence of crust, and surface disturbance due to mixer pump operation during the waste transfer. The methodology was applied to three waste transfers from Tanks AN-105 and AZ-102.
Date: March 12, 2001
Creator: Onishi, Yasuo; Wells, Beric E.; Hartley, Stacey A. & Enderlin, Carl W.
Object Type: Report
System: The UNT Digital Library
External Criticality Risk of Immobilized Plutonium Waste Form in a Geologic Repository (open access)

External Criticality Risk of Immobilized Plutonium Waste Form in a Geologic Repository

This purpose of this technical report is to provide a comprehensive summary of the waste package (WP) external criticality-related risk of the Plutonium Disposition ceramic waste form, which is being developed and evaluated by the Office of Fissile Materials Disposition of the United States Department of Energy (DOE). Potential accumulation of the fissile materials, {sup 239}Pu and {sup 235}U, in rock formations having a favorable chemical environment for such actions, requires analysis because autocatalytic configurations, while unlikely to form, never-the-less have consequences which are undesirable and require evaluation. Secondly, the WP design has evolved necessitating a re-evaluation of the internal WP degradation scenarios that contribute to the external source terms. The scope of this study includes a summary of the revised WP degradation calculations, a summary of the accumulation mechanisms in fractures and lithophysae in the tuff beneath the WP footprint, and a summary of the criticality risk calculations from any accumulated fissile material. Accumulations of fissile material external to the WP sufficient to pose a potential criticality risk require a deposition mechanism operating over sufficient time to reach required levels. The transporting solution concentrations themselves are well below critical levels (CRWMS 2001e). The ceramic waste form consists of Pu …
Date: March 12, 2001
Creator: McClure, J.
Object Type: Report
System: The UNT Digital Library
Development of cryotribological theories & application to cryogenic devices. Final report (open access)

Development of cryotribological theories & application to cryogenic devices. Final report

This is the final report of a research program on low-temperature friction and wear, primarily focused on development of cryotribological theories and application to cryogenic devices, particularly superconducting magnets.
Date: March 12, 2001
Creator: Iwasa, Yukikazu
Object Type: Report
System: The UNT Digital Library
[News Clip: Yates Verdict] captions transcript

[News Clip: Yates Verdict]

Video footage from the KXAS-TV/NBC station in Fort Worth, Texas, to accompany a news story.
Date: March 12, 2001, 10:00 p.m.
Creator: KXAS-TV (Television station : Fort Worth, Tex.)
Object Type: Video
System: The UNT Digital Library
The Baytown Sun (Baytown, Tex.), Vol. 79, No. 106, Ed. 1 Monday, March 12, 2001 (open access)

The Baytown Sun (Baytown, Tex.), Vol. 79, No. 106, Ed. 1 Monday, March 12, 2001

Daily newspaper from Baytown, Texas that includes local, state, and national news along with advertising.
Date: March 12, 2001
Creator: Cash, Wanda Garner
Object Type: Newspaper
System: The Portal to Texas History
Development of a Multi-Layer Guided Wave Inspection Technique (open access)

Development of a Multi-Layer Guided Wave Inspection Technique

This study investigates the inspection of a particular layer of a multi-layer structure using ultrasonic guided waves. Techniques based on Lamb waves have been developed for the inspection of plate structures and are well understood. Guided waves also exist in multi-layered plates as well. Energy distributions vary across the thickness of a multi-layer structure depending on the mode and frequency. Hence, a potential way to inspect the bottom layer of a structure is to find modes with sufficient energy in the bottom layer.
Date: March 12, 2001
Creator: Quarry, M; Chinn, D & Hay, T
Object Type: Report
System: The UNT Digital Library
Science Day Abstracts (open access)

Science Day Abstracts

None
Date: March 12, 2001
Creator: Kline, K
Object Type: Report
System: The UNT Digital Library
Development and Application of a Strength and Damage Model for Rock under Dynamic Loading (open access)

Development and Application of a Strength and Damage Model for Rock under Dynamic Loading

Simulating the behavior of geologic materials under impact loading conditions requires the use of a constitutive model that includes the effects of bulking, yielding, damage, porous compaction and loading rate on the material response. This paper describes the development, implementation and calibration of a thermodynamically consistent constitutive model that incorporates these features. The paper also describes a computational study in which the model was used to perform numerical simulations of PILE DRIVER, a deeply-buried underground nuclear explosion detonated in granite at the Nevada Test Site. Particle velocity histories, peak velocity and peak displacement as a function of slant range obtained from the code simulations compare favorably with PILE DRIVER data. The simulated attenuation of peak velocity and peak displacement also agrees with the results from several other spherical wave experiments in granite.
Date: March 12, 2001
Creator: Antoun, T H; Lomov, I N & Glenn, L A
Object Type: Article
System: The UNT Digital Library
Census 2000: Legal Issues re: Data for Reapportionment and Redistricting (open access)

Census 2000: Legal Issues re: Data for Reapportionment and Redistricting

The release of the 2000 Census data for the apportionment of the House of Representatives among the States and the release of the state redistricting data to the States as required has renewed the decennial debate over several issues. This report contains information regarding the release and use of the State redistricting Census data, the Supreme Court case Utah v. Evans, and related material.
Date: March 12, 2001
Creator: Lee, Margaret Mikyung
Object Type: Report
System: The UNT Digital Library
The Role The Federal Student Loan Programs Play in Supporting Postsecondary Students (open access)

The Role The Federal Student Loan Programs Play in Supporting Postsecondary Students

None
Date: March 12, 2001
Creator: unknown
Object Type: Report
System: The UNT Digital Library
The Oklahoma Daily (Norman, Okla.), Vol. 84, No. 120, Ed. 1 Monday, March 12, 2001 (open access)

The Oklahoma Daily (Norman, Okla.), Vol. 84, No. 120, Ed. 1 Monday, March 12, 2001

Student newspaper of the University of Oklahoma in Norman, Oklahoma that includes national, local, and campus news along with advertising.
Date: March 12, 2001
Creator: McFall, Amy
Object Type: Newspaper
System: The Gateway to Oklahoma History
Altus Times (Altus, Okla.), Vol. 101, No. 310, Ed. 1 Monday, March 12, 2001 (open access)

Altus Times (Altus, Okla.), Vol. 101, No. 310, Ed. 1 Monday, March 12, 2001

Daily newspaper from Altus, Oklahoma that includes local, state, and national news along with advertising.
Date: March 12, 2001
Creator: Bush, Michael
Object Type: Newspaper
System: The Gateway to Oklahoma History
The Alvin Sun (Alvin, Tex.), Vol. 110, No. 21, Ed. 1 Monday, March 12, 2001 (open access)

The Alvin Sun (Alvin, Tex.), Vol. 110, No. 21, Ed. 1 Monday, March 12, 2001

Weekly newspaper from Alvin, Texas that includes local, state, and national news along with advertising.
Date: March 12, 2001
Creator: Schwind, Jim & Holton, Kathleen
Object Type: Newspaper
System: The Portal to Texas History
The Express-Star (Chickasha, Okla.), Ed. 1 Monday, March 12, 2001 (open access)

The Express-Star (Chickasha, Okla.), Ed. 1 Monday, March 12, 2001

Daily newspaper from Chickasha, Oklahoma that includes local, state, and national news along with advertising.
Date: March 12, 2001
Creator: Bush, Kent
Object Type: Newspaper
System: The Gateway to Oklahoma History
[News Clip: SAG Awards] captions transcript

[News Clip: SAG Awards]

B-roll video footage from the KXAS-TV/NBC station in Fort Worth, Texas, to accompany a news story about the SAG Awards.
Date: March 12, 2001, 4:00 p.m.
Creator: KXAS-TV (Television station : Fort Worth, Tex.)
Object Type: Video
System: The UNT Digital Library
Texas Disease Prevention News, Volume 61, Number 6, March 2001 (open access)

Texas Disease Prevention News, Volume 61, Number 6, March 2001

Newsletter of the Texas Department of Health discussing the news, activities, and events of the organization and other information related to health in Texas.
Date: March 12, 2001
Creator: Texas. Department of Health.
Object Type: Journal/Magazine/Newsletter
System: The Portal to Texas History

Ensemble: 2001-03-12 - Baroque Orchestra

Ensemble concert at the UNT College of Music Recital Hall.
Date: March 12, 2001
Creator: University of Nroth Texas. Baroque Orchestra.
Object Type: Sound
System: The UNT Digital Library
Campaign Finance Reform: A Legal Analysis of Issue and Express Advocacy (open access)

Campaign Finance Reform: A Legal Analysis of Issue and Express Advocacy

Issue advocacy communications have become increasingly popular in recent federal election cycles. These advertisements are often interpreted to favor or disfavor certain candidates, while also serving to inform the public about a policy issue. However, unlike communications that expressly advocate the election or defeat of a clearly identified candidate, the Supreme Court has determined that issue ads are constitutionally protected First Amendment speech that cannot be regulated in any manner. According to most lower court rulings, only speech containing express words of advocacy of election or defeat, also known as "express advocacy" or "magic words" can be regulated and therefore be subject to the requirements of the Federal Election Campaign Act (FECA). Unlike express advocacy communications, therefore, issue ads may be paid for with funds unregulated by federal law, i.e., soft money.
Date: March 12, 2001
Creator: Whitaker, L. Paige
Object Type: Report
System: The UNT Digital Library
Sapulpa Daily Herald (Sapulpa, Okla.), Vol. 86, No. 153, Ed. 1 Monday, March 12, 2001 (open access)

Sapulpa Daily Herald (Sapulpa, Okla.), Vol. 86, No. 153, Ed. 1 Monday, March 12, 2001

Daily newspaper from Sapulpa, Oklahoma that includes local, state, and national news along with advertising.
Date: March 12, 2001
Creator: Quinnelly, Lorrie J.
Object Type: Newspaper
System: The Gateway to Oklahoma History
A decisional process model for stewardship. (open access)

A decisional process model for stewardship.

The U.S. Department of Energy (DOE), other federal agencies, state agencies, and the private sector pursuing environmental remediation programs are considering developing stewardship programs at contaminated sites that might not be remediated to the point of allowing unrestricted land use in the immediate future. Deciding to develop, implement, and monitor a stewardship program requires addressing the risks and costs inherent in such programs. A process that lays out the decision points and information and technology needs associated with these risks and costs would assist site managers, regulators, and members of the interested public in making decisions about full remediation versus stewardship programs and the management of such programs. Development of such a process is the subject of this report. The goals for development and use of this decisional process are twofold. The first goal is to help decision makers determine whether a stewardship program would be appropriate for a site and, if so, how to design it. The term ''decision makers'' is used in a very broad sense to include everyone with an interest in the site, even though they have varying degrees of authority and responsibility for decisions regarding the site. Site decision makers can include personnel responsible for …
Date: March 12, 2001
Creator: Hocking, E.; Johnson, R.; Martino, L. & Elcock, D.
Object Type: Report
System: The UNT Digital Library
Material Balance Assessment for Double-Shell Tank Waste Pipeline Transfer (open access)

Material Balance Assessment for Double-Shell Tank Waste Pipeline Transfer

PNNL developed a material balance assessment methodology based on conservation of mass for detecting leaks and mis-routings in pipeline transfer of double-shell tank waste at Hanford. The main factors causing uncertainty in these transfers are variable property and tank conditions of density, existence of crust, and surface disturbance due to mixer pump operation during the waste transfer. The methodology was applied to three waste transfers from Tanks AN-105 and AZ-102.
Date: March 12, 2001
Creator: Onishi, Yasuo; Wells, Beric E; Hartley, Stacey A & Enderlin, Carl W
Object Type: Report
System: The UNT Digital Library
Photovoltaic Manufacturing Cost and Throughput Improvements for Thin-Film CIGS-Based Modules; Phase II Annual Subcontract Technical Report, July 1999 - August 2000 (open access)

Photovoltaic Manufacturing Cost and Throughput Improvements for Thin-Film CIGS-Based Modules; Phase II Annual Subcontract Technical Report, July 1999 - August 2000

Thin-film photovoltaics (PV) has expanded dramatically in the last five years, but commercial use remains limited by performance, cost, and reliability. Of all the thin-film systems, copper indium gallium diselenide (CIGS) has demonstrated the greatest potential for achieving high performance at a low cost. The highest-quality CIGS has been formed by multi-source co-evaporation, a technique pioneered in this country by researchers at NREL. Multi-source co-evaporation is also potentially the fastest and most cost-effective method of CIGS absorber deposition. Global Solar Energy (GSE) has adapted multi-source co-evaporation of CIGS to large-area, roll-to-roll processing on flexible substrates, enabling several manufacturing and product capability advantages. Roll-to-roll processing enables a low-cost, automated continuous manufacturing process. Flexible substrates enable product application in unique, as well as traditional, areas. The primary objectives of the GSE Photovoltaic Manufacturing Technology (PVMaT) subcontract are to reduce cost and expand the production rate of thin-film CIGS-based PV modules on flexible substrates. Improvements will be implemented in monolithic integration, CIGS deposition, contact deposition, and in-situ CIGS control and monitoring. Specific goals of the three-year contract are: - Monolithic Integration - Increase integration speed by developing high-speed, all-laser scribing processes that are more than 100% faster than the baseline process and offer …
Date: March 12, 2001
Creator: Wendt, T.G. & Wiedeman, S. (Global Solar Energy, L.L.C.)
Object Type: Report
System: The UNT Digital Library
PVMaT Improvements in the BP Solarex Photovoltaic Module Manufacturing Technology: Annual Report, May 5, 1999 - June 15, 2000 (open access)

PVMaT Improvements in the BP Solarex Photovoltaic Module Manufacturing Technology: Annual Report, May 5, 1999 - June 15, 2000

This is the annual report for a 3-year PV program to continue to advance BP Solarex photovoltaic manufacturing technologies to design and implement a process that produces polycrystalline silicon PV modules that can be sold profitably for $2.00 per peak watt or less, and which increases the production capacity of the Frederick plant to at least 25 megawatts per year. The accomplishments discussed in this report include: (1) developed processes to produce high-purity SiF4 gas from a number of available commercial sources; (2) designed and implemented a new control system for casting; (3) verified relationship between higher minority-carrier lifetime in cast Si and cell efficiency; tracking material quality by measuring minority-carrier lifetime for each production casting; (4) reduced the wire-saw pitch to 450 microns with no loss in downstream yield; (5) demonstrated 8% improvement in average cell power on pre-production trial lots using PECVD silicon nitride; (6) developed a new EVA formation and demonstrated a 6-minute process to achieve adequate cure of PV modules in standard lamination equipment; (7) designed, purchased, and installed a new automated assembly line for large-area modules; and (8) implemented a factory-wide data collection and tracking system; production volumes and performance parameters are now monitored in …
Date: March 12, 2001
Creator: Wohlgemuth, J. & Shea, S. (BP Solarex)
Object Type: Report
System: The UNT Digital Library