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Brittle and Ductile Behavior in Carbon Nanotubes (open access)

Brittle and Ductile Behavior in Carbon Nanotubes

Article discussing research on the response of carbon nanotubes to a tensile load.
Date: November 23, 1998
Creator: Buongiorno Nardelli, Marco; Yakobson, Boris I. & Bernholc, Jerry
Object Type: Article
System: The UNT Digital Library

[Photograph 2012.201.B0272.0713]

Photograph used for a story in the Daily Oklahoman newspaper. Caption: "Joe Ihle and an automated shaker bring pecans to the ground."
Date: November 23, 1998
Creator: Argo, Joe
Object Type: Photograph
System: The Gateway to Oklahoma History
Revenue Provisions in Annual Appropriations Acts (open access)

Revenue Provisions in Annual Appropriations Acts

None
Date: November 23, 1998
Creator: unknown
Object Type: Report
System: The UNT Digital Library

[Photograph 2012.201.B0272.0713]

Photograph used for a story in the Daily Oklahoman newspaper. Caption: "Joe Ihle and an automated shaker bring pecans to the ground."
Date: November 23, 1998
Creator: Argo, Joe
Object Type: Photograph
System: The Gateway to Oklahoma History
Predicting Ultimate Loads for Wind Turbine Design (open access)

Predicting Ultimate Loads for Wind Turbine Design

This paper addresses the statistical uncertainty of loads prediction using structural dynamics simulation codes and the requirements for the number and duration of simulations for obtaining robust load estimates.
Date: November 23, 1998
Creator: Madsen, P. H.; Pierce, K. & Buhl, M.
Object Type: Article
System: The UNT Digital Library
Decontamination and dismantlement of the building 594 waste ion exchange facility at Argonne National Laboratory-East project final report. (open access)

Decontamination and dismantlement of the building 594 waste ion exchange facility at Argonne National Laboratory-East project final report.

The Building 594 D&D Project was directed toward the following goals: Removal of any radioactive and hazardous materials associated with the Waste Ion Exchange Facility; Decontamination of the Waste Ion Exchange Facility to unrestricted use levels; Demolition of Building 594; and Documentation of all project activities affecting quality (i.e., waste packaging, instrument calibration, audit results, and personnel exposure) These goals had been set in order to eliminate the radiological and hazardous safety concerns inherent in the Waste Ion Exchange Facility and to allow, upon completion of the project, unescorted and unmonitored access to the area. The ion exchange system and the resin contained in the system were the primary areas of concern, while the condition of the building which housed the system was of secondary concern. ANL-E health physics technicians characterized the Building 594 Waste Ion Exchange Facility in September 1996. The characterization identified a total of three radionuclides present in the Waste Ion Exchange Facility with a total activity of less than 5 {micro}Ci (175 kBq). The radionuclides of concern were Co{sup 60}, Cs{sup 137}, and Am{sup 241}. The highest dose rates observed during the project were associated with the resin in the exchange vessels. DOE Order 5480.2A establishes …
Date: November 23, 1998
Creator: Wiese, E. C.
Object Type: Report
System: The UNT Digital Library
An SXF Extension for Alignment (open access)

An SXF Extension for Alignment

None
Date: November 23, 1998
Creator: W., Ficsher & Pilat, F.
Object Type: Report
System: The UNT Digital Library
The Baytown Sun (Baytown, Tex.), Vol. 77, No. 20, Ed. 1 Monday, November 23, 1998 (open access)

The Baytown Sun (Baytown, Tex.), Vol. 77, No. 20, Ed. 1 Monday, November 23, 1998

Daily newspaper from Baytown, Texas that includes local, state, and national news along with advertising.
Date: November 23, 1998
Creator: Dobbs, Gary
Object Type: Newspaper
System: The Portal to Texas History
Altus Times (Altus, Okla.), Vol. 99, No. 217, Ed. 1 Monday, November 23, 1998 (open access)

Altus Times (Altus, Okla.), Vol. 99, No. 217, Ed. 1 Monday, November 23, 1998

Daily newspaper from Altus, Oklahoma that includes local, state, and national news along with advertising.
Date: November 23, 1998
Creator: Cole, Carol
Object Type: Newspaper
System: The Gateway to Oklahoma History
The Alvin Sun (Alvin, Tex.), Vol. 108, No. 32, Ed. 1 Monday, November 23, 1998 (open access)

The Alvin Sun (Alvin, Tex.), Vol. 108, No. 32, Ed. 1 Monday, November 23, 1998

Weekly newspaper from Alvin, Texas that includes local, state, and national news along with advertising.
Date: November 23, 1998
Creator: Schwind, Jim & Looby, Edward
Object Type: Newspaper
System: The Portal to Texas History
The Town Tattler (Electra, Tex.), Vol. 66, No. 47, Ed. 1 Monday, November 23, 1998 (open access)

The Town Tattler (Electra, Tex.), Vol. 66, No. 47, Ed. 1 Monday, November 23, 1998

Weekly newspaper from Electra, Texas that includes local and regional news along with advertising.
Date: November 23, 1998
Creator: unknown
Object Type: Newspaper
System: The Portal to Texas History
[E-mail from Melinda Mayer to D. Jack Davis, Nancy Walkup, and Pam Stephens, November 23, 1998] (open access)

[E-mail from Melinda Mayer to D. Jack Davis, Nancy Walkup, and Pam Stephens, November 23, 1998]

An e-mail from Melinda Mayer to D. Jack Davis, Pam Stephens, and Nancy Walkup about the need to notify art specialist and principals about an upcoming leadership retreat.
Date: November 23, 1998
Creator: Mayer, Melinda
Object Type: Letter
System: The UNT Digital Library
Superfund Reauthorization Issues in the 105th Congress (open access)

Superfund Reauthorization Issues in the 105th Congress

For the third Congress in a row, there was a major effort to reauthorize Superfund. Chairmen of the three committees of jurisdiction introduced comprehensive reauthorization bills -- S. 8, H.R. 2727, and H.R. 3000; hearings were held on all three, S. 8 was ordered reported, and H.R. 2727 was approved by subcommittee. None of these bills was enacted.
Date: November 23, 1998
Creator: Reisch, Mark
Object Type: Report
System: The UNT Digital Library
Marine Dead Zones: Understanding the Problem (open access)

Marine Dead Zones: Understanding the Problem

Very low levels of dissolved oxygen (hypoxia) in bottom-water "dead zones" are natural phenomena, but can be intensified by certain human activities. The largest hypoxic area affecting the United States is in the northern Gulf of Mexico near the mouth of the Mississippi River, but there are others as well.
Date: November 23, 1998
Creator: Dandelski, John R. & Buck, Eugene H.
Object Type: Report
System: The UNT Digital Library
Department of Energy FY1999 Research and Development Budget: Description and Analysis (open access)

Department of Energy FY1999 Research and Development Budget: Description and Analysis

This report focuses on the R&D programs. It divides the programs into four categories: energy resources R&D, science, national security R&D, and environmental quality R&D. Those categories, which approximate the way DOE has divided up its programs, are set up to keep similar research activities together.(1) R&D funding is concentrated in the first three. The report gives a description of the programs within each category including their research objectives and the activities where significant budget changes were requested for FY1999. It then describes the request, and congressional appropriation and authorization action. There follows a discussion of issues about the FY1999 request that are emerging during congressional consideration of the budget.
Date: November 23, 1998
Creator: Rowberg, Richard E.
Object Type: Report
System: The UNT Digital Library
Sapulpa Daily Herald (Sapulpa, Okla.), Vol. 84, No. 60, Ed. 1 Monday, November 23, 1998 (open access)

Sapulpa Daily Herald (Sapulpa, Okla.), Vol. 84, No. 60, Ed. 1 Monday, November 23, 1998

Daily newspaper from Sapulpa, Oklahoma that includes local, state, and national news along with advertising.
Date: November 23, 1998
Creator: Horn, Richard A.
Object Type: Newspaper
System: The Gateway to Oklahoma History
Rocketdyne Propulsion and Power DOE Operations annual site environmental report 1997 (open access)

Rocketdyne Propulsion and Power DOE Operations annual site environmental report 1997

This annual report discusses environmental monitoring at two manufacturing and test sites operated in the Los Angeles area by Rocketdyne Propulsion and Power of Boeing North American, Inc. These are identified as Area 4 of the SSFL and the De Soto site. These sites have been used for research and development (R and D), engineering, and testing in a broad range of technical fields primarily in energy research and nuclear reactor technology. The De Soto site had research and development laboratories involved with nuclear research. This work was terminated in 1995 and only D and D activities will have potential for impact on the environment. Since 1956, Area 4 has been used for work with nuclear materials, including fabricating nuclear reactor fuels, testing nuclear reactors, and dissembling used fuel elements. This work ended in 1988 and subsequent efforts have been directed toward decommissioning and decontamination of the former nuclear facilities. The primary purpose of this report is to present information on environmental and effluent monitoring of DOE-sponsored activities to the regulatory agencies responsible for oversight. Information presented here concentrates on Area 4 at SSFL, which is the only area at SSFL where DOE operations were performed.
Date: November 23, 1998
Creator: Robinson, K.S.
Object Type: Report
System: The UNT Digital Library
Inductively Coupled Plasma Etching in ICl- and IBr-Based Chemistries: Part I. GaAs, GaSb and AlGaAs (open access)

Inductively Coupled Plasma Etching in ICl- and IBr-Based Chemistries: Part I. GaAs, GaSb and AlGaAs

High density plasma etching of GaAs, GaSb and AIGaAs was performed in IC1/Ar and lBr/Ar chemistries using an Inductively Coupled Plasma (ICP) source. GaSb and AlGaAs showed maxima in their etch rates for both plasma chemistries as a function of interhalogen percentage, while GaAs showed increased etch rates with plasma composition in both chemistries. Etch rates of all materials increased substantially with increasing rf chuck power, but rapidly decreased with chamber pressure. Selectivities > 10 for GaAs and GaSb over AlGaAs were obtained in both chemistries. The etched surfaces of GaAs showed smooth morphology, which were somewhat better with IC1/Ar than with IBr/& discharge. Auger Electron Spectroscopy analysis revealed equi-rate of removal of group III and V components or the corresponding etch products, maintaining the stoichiometry of the etched surface.
Date: November 23, 1998
Creator: Abernathy, C.R.; Cho, H.; Hahn, Y.B.; Hays, D.C.; Hobson, W.S.; Jung, K.B. et al.
Object Type: Article
System: The UNT Digital Library
A Feature Extraction Toolbox for Pattern Recognition Application (open access)

A Feature Extraction Toolbox for Pattern Recognition Application

Feature extraction and evaluation are procedures common to the development of all pattern recognition application. These features are the primary pieces of information used to train the pattern recognition engine, whether that engine is a neural network, a fuzzy logic rulebase, or a genetic algorithm. Careful selection of the features to be used by the pattern recognition engine can significantly streamline the overall development and training of the solution for the pattern recognition application. Presently, AlliedSignal Federal Manufacturing & Technologies (FM&T) is developing an integrated, computer-based software package, called the Feature Extraction Toolbox. This package will be used for developing and deploying solutions to generic pattern recognition problems. The toolbox integrates a variety of software techniques for signal processing, feature extraction and evaluation, and pattern recognition, under a single, user-friendly developmental environment. While a feature extraction toolbox can help in the selection process, it is the user that ultimately must make all decisions. A prototype version of this toolbox has been developed and currently is being used for applications development on several projects in support of the Department of Energy. The toolbox has been developed to run on a laptop computer so that it can be taken to a site …
Date: November 23, 1998
Creator: Baumgart, C. W.; Linder, K. E. & Nelson, L. K.
Object Type: Article
System: The UNT Digital Library
Reactive Ion Beam Etching of GaAs and Related Compounds in an Inductively Coupled Plasma of Cl(2)-Ar Mixture (open access)

Reactive Ion Beam Etching of GaAs and Related Compounds in an Inductively Coupled Plasma of Cl(2)-Ar Mixture

Reactive ion beam etching (RD3E) of GaAs, GaP, AIGaAs and GaSb was performed in a Cl2-Ar mixture using an Inductively Coupled Plasma (ICP) source. `The etch rates and yields were strongly affected by ion energy and substrate temperature. The RJBE was dominated by ion-assisted etching at <600 eV and by physical sputtering beyond 600 eV. The temperature dependence of the etch rates revealed three different regimes, depending on the substrate temperature: 1) sputtering-etch limited, 2) products-resorption limited, and 3) mass-transfer limited regions. GaSb showed the overall highest etch rates, while GaAs and AIGaAs were etched at the same rates. The etched features showed extremely smooth morphologies with anisotropic sidewalls.
Date: November 23, 1998
Creator: Abernathy, C. R.; Hahn, Y. B.; Hays, D.; Lambers, E. S.; Lee, J. W.; Pearton, S. J. et al.
Object Type: Article
System: The UNT Digital Library
Synthesis of Sol-Gel Matrices for Encapsulation of Enzymes Using an Aqueous Route (open access)

Synthesis of Sol-Gel Matrices for Encapsulation of Enzymes Using an Aqueous Route

Sol-gel matrices are promising host materials for potential chemical and biosensor applications. Previous studies have focused on modified sol-gel routes using alkoxides for encapsulation of enzymes. However the formation of alcohol as a byproduct during hydrolysis and condensation reactions poses limitations. We report the immobilization of glucose oxidase and peroxidase in silica prepared by an aqueous route which may provide a more favorable environment for the biomolecules. A two step aqueous sol-gel procedure using sodium silicate as the precursor was developed to encapsulate the enzymes and the dye precursor, o-dianisidine. Glucose oxidase catalyzes the oxidation of glucose to give gluconic acid and hydrogen peroxide. Peroxidase then catalyzes the reaction of the dye precursor with hydrogen peroxide to produce a colored product. The kinetics of the coupled enzymatic reactions were monitored by optical spectroscopy and compared to those occurring in tetramethyl orthosilicate (TMOS) derived silica matrices developed by Yamanaka. Enhanced kinetics in the aqueous silicate matrices were related to differences in the host microstructure as elucidated by microstructural comparisons of the corresponding aerogels.
Date: November 23, 1998
Creator: Ashley, C. S.; Bhatia, R. B.; Brinker, C. J. & Harris, T. M.
Object Type: Article
System: The UNT Digital Library
Modeling Coal Seam Damage in Cast Blasting (open access)

Modeling Coal Seam Damage in Cast Blasting

A discrete element computer program named DMC_BLAST (Distinct Motion Code) has been under development since 1987 for modeling rock blasting (Preece & Taylor, 1989). This program employs explicit time integration and uses spherical or cylindrical elements that are represented as circles in two dimensions. DMC_BLAST calculations compare favorably with data from actual bench blasts (Preece et al, 1993). Coal seam chilling refers to the shattering of a significant portion of the coal leaving unusable fines. It is also refereed to as coal damage. Chilling is caused during a blast by a combination of explosive shock energy and movement of the adjacent rock. Chilling can be minimized by leaving a buffer zone between the bottom of the blastholes and the coal seam or by changing the blast design to decrease the powder factor or by a combination of both. Blast design in coal mine cast blasting is usually a compromise between coal damage and rock fragmentation and movement (heave). In this paper the damage to coal seams from rock movement is examined using the discrete element computer code DMC_BLAST. A rock material strength option has been incorporated into DMC_BLAST by placing bonds/links between the spherical particles used to model the rock. …
Date: November 23, 1998
Creator: Chung, S.H. & Preece, D.S.
Object Type: Article
System: The UNT Digital Library
1997 Atmospheric Chemistry Colloquium for Emerging Senior Scientists (open access)

1997 Atmospheric Chemistry Colloquium for Emerging Senior Scientists

DOE's Atmospheric Chemistry Program is providing partial funding for the Atmospheric Chemistry Colloquium for Emerging Senior Scientists (ACCESS) and FY 1997 Gordon Research Conference in Atmospheric Chemistry
Date: November 23, 1998
Creator: Wine, Paul H.
Object Type: Article
System: The UNT Digital Library
Managing Reliability in the 21st Century (open access)

Managing Reliability in the 21st Century

The rapid pace of change at Ike end of the 20th Century should continue unabated well into the 21st Century. The driver will be the marketplace imperative of "faster, better, cheaper." This imperative has already stimulated a revolution-in-engineering in design and manufacturing. In contrast, to date, reliability engineering has not undergone a similar level of change. It is critical that we implement a corresponding revolution-in-reliability-engineering as we enter the new millennium. If we are still using 20th Century reliability approaches in the 21st Century, then reliability issues will be the limiting factor in faster, better, and cheaper. At the heart of this reliability revolution will be a science-based approach to reliability engineering. Science-based reliability will enable building-in reliability, application-specific products, virtual qualification, and predictive maintenance. The purpose of this paper is to stimulate a dialogue on the future of reliability engineering. We will try to gaze into the crystal ball and predict some key issues that will drive reliability programs in the new millennium. In the 21st Century, we will demand more of our reliability programs. We will need the ability to make accurate reliability predictions that will enable optimizing cost, performance and time-to-market to meet the needs of every …
Date: November 23, 1998
Creator: Dellin, T.A.
Object Type: Article
System: The UNT Digital Library