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Record of Technical Change No.1 for ``Fluid Management Plan for the Project Shoal Area Off-sites Project''
This Record of Technical Change provides updates to the technical information included in the ``Fluid Management Plan for the Project Shoal Area Off-sites Project,'' April 1999
Date:
November 22, 1999
Creator:
/NV, USDOE
Object Type:
Report
System:
The UNT Digital Library
Record of Technical Change No.2 for ``Corrective Action Investigation Plan for Corrective Action Unit 143: Area 25 Contaminated Waste Dumps, Nevada Test Site, Nevada''
This Record of Technical Change provides updates to the technical information included in ``Corrective Action Investigation Plan for Corrective Action Unit 143: Area 25 Contaminated Waste Dumps, Nevada Test Site, Nevada.''
Date:
November 19, 1999
Creator:
/NV, USDOE
Object Type:
Report
System:
The UNT Digital Library
Micromilling of Metal Alloys with Focused Ion Beam-Fabricated Tools
This work combines focused ion beam sputtering and ultra-precision machining as a first step in fabricating microstructure in metals and alloys. Specifically, {approx}25{micro}m diameter micro-end mills are made from cobalt M42 high-speed steel and C2 micrograin tungsten carbide tool blanks by ion beam sputtering. A 20 keV focused gallium beam defines tool cutting edges having radii of curvature < 0.1{micro}m. Micro-end mills having 2, 4 and 5 cutting edges successfully machine small trenches in 6061-T4 aluminum, brass, 4340 steel and polymethyl methacrylate. Machined trench widths are approximately equal to the tool diameters and surface roughnesses (rms) are {approx}150 nm or less. Microtools are robust and operate for more than 6 hours without fracture. Results from ultra-precision machining aluminum at feed rates as high as 50 mm/minute are included.
Date:
November 5, 1999
Creator:
ADAMS,DAVID P.; VASILE,M.J.; BENAVIDES,GILBERT L. & CAMPBELL,ANN N.
Object Type:
Article
System:
The UNT Digital Library
Periodic Boundary Conditions in the ALEGRA Finite Element Code
This document describes the implementation of periodic boundary conditions in the ALEGRA finite element code. ALEGRA is an arbitrary Lagrangian-Eulerian multi-physics code with both explicit and implicit numerical algorithms. The periodic boundary implementation requires a consistent set of boundary input sets which are used to describe virtual periodic regions. The implementation is noninvasive to the majority of the ALEGRA coding and is based on the distributed memory parallel framework in ALEGRA. The technique involves extending the ghost element concept for interprocessor boundary communications in ALEGRA to additionally support on- and off-processor periodic boundary communications. The user interface, algorithmic details and sample computations are given.
Date:
November 1, 1999
Creator:
AIDUN,JOHN B.; ROBINSON,ALLEN C. & WEATHERBY,JOE R.
Object Type:
Report
System:
The UNT Digital Library
Antireflection Coating Design for Series Interconnected Multi-Junction Solar Cells
AR coating design for multi-junction solar cells can be more challenging than in the single junction case. Reasons for this are discussed. Analytical expressions used to optimize AR coatings for single junction solar cells are extended for use in monolithic, series interconnected multi-junction solar cell AR coating design. The result is an analytical expression which relates the solar cell performance (through J{sub SC}) directly to the AR coating design through the device reflectance. It is also illustrated how AR coating design can be used to provide an additional degree of freedom for current matching multi-junction devices.
Date:
November 29, 1999
Creator:
AIKEN,DANIEL J.
Object Type:
Article
System:
The UNT Digital Library
Salinas - User's Notes
Salinas provides a massively parallel implementation of structural dynamics finite element analysis, required for high fidelity, validated models used in modal, vibration, static and shock analysis of weapons systems. This document provides a users guide to the input for Salinas. Details of input specifications for the different solution types, output options, element types and parameters are included. The appendices contain detailed examples, and instructions for running the software on parallel platforms.
Date:
November 1, 1999
Creator:
ALVIN,KENNETH F.; BHARDWAJ,MANOJ K.; DRIESSEN,BRIAN; REESE,GARTH M. & SEGALMAN,DANIEL J.
Object Type:
Report
System:
The UNT Digital Library
DESIGN AND ANALYSIS OF THE SNS CCL HOT MODEL WATER COOLING SYSTEM USING THE SINDA/FLUINT NETWORK MODELING TOOL
This report presents results for design and analysis of the hot model water cooling system for the Spallation Neutron Source (SNS) coupled-cavity linac (CCL). The hot model, when completed, will include segments for both the CCL and coupled-cavity drift-tube linac (CCDTL). The scope of this report encompasses the modeling effort for the CCL portion of the hot model. This modeling effort employed the SINDA/FLUINT network modeling tool. This report begins with an introduction of the SNS hot model and network modeling using SINDA/FLUINT. Next, the development and operation of the SINDA/FLUINT model are discussed. Finally, the results of the SINDA/FLUINT modeling effort are presented and discussed.
Date:
November 1, 1999
Creator:
AMMERMAN, C. & BERNARDIN, J.
Object Type:
Report
System:
The UNT Digital Library
STATUS OF THE ACCELERATOR PRODUCTION OF TRITIUM (APT) PROJECT
None
Date:
November 1, 1999
Creator:
ANDERSON, J. L.; LISOWSKI, P. W. & AL, ET
Object Type:
Article
System:
The UNT Digital Library
DEVELOPMENT OF REMOTE MONITORING SYSTEM FOR THE UNATTENDED MODE NDA IN PFPF
None
Date:
November 1, 1999
Creator:
ASAKURA, K.; OHTANI, T. & AL, ET
Object Type:
Article
System:
The UNT Digital Library
Roles and Delegation of Authority (R/DA) System
The processes of defining managerial roles and providing for delegation of authority are essential to any enterprise. At most large organizations, these processes are defined in policy manuals and through sets of standard operating procedures for many, if not all, business and administrative functions. Many of these staff-initiated, administrative functions require the routing of documents for approval to one or more levels of management. These employee-oriented, back office types of workflows tend to require more flexibility in determining to whom these documents should go to, while, at the same time, providing the responsible parties with the flexibility to delegate their approval authority or allow others to review their work. Although this practice is commonplace in manual, paper-based processes that exist in many organizations, it is difficult to provide the same flexibility in the more structured, electronic-based, workflow systems. The purpose of this report is to present a framework or architecture for creating a R/DA system and provide some insights associated with its design and utilization. To improve understanding and clarify subsequent discussion, the goals and requirements for the major R/DA system components, namely, the database and interface modules, are initially presented along with the identification of important concepts and the …
Date:
November 1, 1999
Creator:
Abbott, John P.; Hutchins, James C. & Schoch, David G.
Object Type:
Report
System:
The UNT Digital Library
Using Cytochrome c{sub 3} to Make Selenium Nanowires
We report on a new method to make nanostructures, in this case selenium nanowires, in aqueous solution at room temperature. We used the protein cytochrome c{sub 3} to reduce selenate (SeO{sub 4}{sup 2{minus}}) to selenium (Se{sup 0}). Cytochrome c{sub 3} is known for its ability to catalyze reduction of metals including U{sup VI} {yields} U{sup IV}, Cr{sup VI} {yields} Cr{sup III}, Mo{sup VI} {yields} Mo{sup IV}, Cu{sup II} {yields} Cu{sup 0}, Pb{sup II} {yields} Pb{sup 0}, Hg{sup II} {yields} Hg{sup 0}. Nanoparticles of Se{sup 0} precipitated from an aqueous solution at room temperature, followed by spontaneous self-assembling into nanowires. Cytochrome c{sub 3} was extracted from the sulfate-reducing bacteria Desulfovibrio vulgaris (strain Holdenborough) and isolated by the procedure of DerVartanian and Legall.
Date:
November 24, 1999
Creator:
Abdelouas, A.; Franco, R.; Gong, W. L.; Lutze, W.; Moura, I. & Shelnutt, John A.
Object Type:
Article
System:
The UNT Digital Library
Facet Model and Mathematical Morphology for Surface Characterization
This paper describes an algorithm for the automatic segmentation and representation of surface structures and non-uniformities in an industrial setting. The automatic image processing and analysis algorithm is developed as part of a complete on-line web characterization system of a papermaking process at the wet end. The goal is to: (1) link certain types of structures on the surface of the web to known machine parameter values, and (2) find the connection between detected structures at the beginning of the line and defects seen on the final product. Images of the pulp mixture (slurry), carried by a fast moving table, are obtained using a stroboscopic light and a CCD camera. This characterization algorithm succeeded where conventional contrast and edge detection techniques failed due to a poorly controlled environment. The images obtained have poor contrast and contain noise caused by a variety of sources. After a number of enhancement steps, conventional segmentation methods still f ailed to detect any structures and are consequently discarded. Techniques tried include the Canny edge detector, the Sobel, Roberts, and Prewitt's filters, as well as zero crossings. The facet model algorithm, is then applied to the images with various parameter settings and is found to be …
Date:
November 13, 1999
Creator:
Abidi, B.R.; Goddard, J.S.; Hunt, M.A. & Sari-Sarraf, H.
Object Type:
Article
System:
The UNT Digital Library
Computational Analysis of Heat Flow Calorimeters
None
Date:
November 28, 1999
Creator:
Aboagye, Steve A. & Ball, Kenneth S.
Object Type:
Article
System:
The UNT Digital Library
Volatilization of Fission Products from Metallic Melts in the Melt-Dilute Treatment Technology Development for Al-Based DOE Spent Nuclear Fuels
The melt-dilute treatment technology is being developed to facilitate the ultimate disposition of highly enriched Al-Base DOE spent nuclear fuels in a geologic repository such as that proposed for Yucca Mountain. Currently, approximately 28 MTHM is expected to be returned to the Savannah River Site from domestic and foreign research reactors. The melt-dilute treatment technology will melt the fuel assemblies to reduce their volume and alloys them with depleted uranium to isotopically dilute the 235U concentration. The resulting alloy is cast into a form for long term geologic repository storage. Benefits accrued from the melt-dilute process include the potential for significant volume reduction; reduced criticality potential, and proliferation concerns. A critical technology element in the development of the melt-dilute process is the development of offgas system requirements. The volatilization of radioactive species during the melting stage of the process primarily constitutes the offgas in this process. Several of the species present following irradiation of a fuel assembly have been shown to be volatile or semi-volatile under reactor core melt-down conditions. Some of the key species that have previously been studied are krypton, iodine, and cesium. All of these species have been shown to volatilize during melting experiments however, the degree …
Date:
November 18, 1999
Creator:
Adams, T.
Object Type:
Article
System:
The UNT Digital Library
Ion Beam Sputter Fabrication of Micro-Grooving and Micro-Threading Tools
This paper presents techniques for fabricating microscopic, nonplanar features in a variety of materials. Micro-grooving and micro-threading tools having cutting dimensions of 10-30{micro}m are made by focused ion beam sputtering and used in ultra-precision machining. Tool fabrication involves directing a 20 keV gallium beam at polished cylindrical punches made of cobalt M42 high-speed steel or C2 tungsten carbide. This creates cutting edges having radii of curvature less than 0.4 {micro}m, and rake features similar to conventional lathe tools. Clearance for minimizing frictional drag of a tool results from the sputter yield dependence on ion herd target incidence angle. Numerically controlled, ultra-precision machining with micro-grooving tools results in a close matching between tool width and feature size. Microtools controllably machine 13 {micro}m wide, 4 {micro}m deep, helical grooves in polymethyl methacrylate and 6061-T6 Al cylindrical substrates. Micro-grooving tools also fabricate sinusoidal waveform features in polished metal substrates.
Date:
November 5, 1999
Creator:
Adams,David P.; Vasile,M. J. & Krishnan,A. S. M.
Object Type:
Article
System:
The UNT Digital Library
Ensemble: 1999-11-08 - Les Petits Violons
Concert presented at the UNT College of Music Recital Hall.
Date:
November 8, 1999
Creator:
Adkins, Cecil
Object Type:
Sound
System:
The UNT Digital Library
Final report: Efficient thyratron modulator project
The purpose of this program was to examine methods of increasing the efficiency of producing pulses to drive Klystrons in the 150 MW range. This may include 2 Klystrons in the 75 MW range. Specific methods of interest to improve the pulse efficiency were the use of a circuit to add energy to the tail of the pulse, the use of a bipyrimidal transformer, and the use of gas insulation as a means of improving the pulse shape. These methods were investigated using both thyratron and IGBT switching. The low cost designs developed in this work consisted of low voltage designs which don't require the oil immersion. These designs can be ''hot tuned'' based on the use of simple, tunable inductors.
Date:
November 26, 1999
Creator:
Adler, R. J.; Richter-Sand, R. J. & Gregg, C. W.
Object Type:
Report
System:
The UNT Digital Library
Mesoscale Engineering of Nanocomposite Nonlinear Optical Materials
Complex nonlinear optical materials comprising elemental, compound or alloy quantum dots embedded in appropriate dielectric or semiconducting hosts may be suitable for deployment in photonic devices. Ion implantation, ion exchange followed by ion implantation, and pulsed laser deposition have ail been used to synthesize these materials. However, the correlation between the parameters of energetic-beam synthesis and the nonlinear optical properties is still very rudimentary when one starts to ask what is happening at nanoscale dimensions. Systems integration of complex nonlinear optical materials requires that the mesoscale materials science be well understood within the context of device structures. We discuss the effects of beam energy and energy density on quantum-dot size and spatial distribution, thermal conductivity, quantum-dot composition, crystallinity and defects - and, in turn, on the third-order optical susceptibility of the composite material. Examples from recent work in our laboratories are used to illustrate these effects.
Date:
November 1, 1999
Creator:
Afonso, C.N.; Feldman, L.C.; Gonella, F.; Haglund, R.F.; Luepke, G.; Magruder, R.H. et al.
Object Type:
Article
System:
The UNT Digital Library
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 research 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:
November 30, 1999
Creator:
Akyurtlu, Ates & Akyurtlu, Jale F.
Object Type:
Report
System:
The UNT Digital Library
Local Probe into the Atomic Structure of Metallic Glasses using EELS
Electron energy loss spectroscopy (EELS) is used to extract information on the topological arrangement of atoms around Pd in the bulk-glass-forming Pd{sub 60}Ni{sub 20}P{sub 20}. It is found that the environment around Pd in the glass is only a slight modification of the Pd crystalline structure. However, the modification is enough to allow this alloy to form a glass in bulk. In examining the differences between the structure of crystalline Pd and glassy Pd{sub 60}Ni{sub 20}P{sub 20} it is concluded that incorporation of Ni and P into the structure frustrates the structure enough that glass formation becomes easy.
Date:
November 30, 1999
Creator:
Alamgir, F. M.; Ito, Y.; Schwarz, R. B.; Jain, H. & Williams, D. B.
Object Type:
Article
System:
The UNT Digital Library
Oral History Interview with Wilbur H. Ford, November 18, 1999
Access:
Use of this item is restricted to the UNT Community
Interview with Army Air Forces veteran Wilbur H. Ford. The interview includes Ford's personal experiences about being a B-17 pilot in the European Theater during World War II, training, transferring to the Army Air Force from the Army, flight training, B-17 transition training, and crew training. Ford also talks about his assignment to the 401st Bomb Group, enemy flak, the highlights of his nine missions over Germany, battle damage to his plane, the Dresden raid, returning to the States, and transition training in B-29s for transfer to the Pacific Theater.
Date:
November 18, 1999
Creator:
Alexander, William J. & Ford, Wilbur H.
Object Type:
Book
System:
The UNT Digital Library
Deep Levels in p- and n-type InGaAsN for High Efficiency Multi-Junction III-V Solar Cells
Red Teaming is an advanced form of assessment that can be used to identify weaknesses in a variety of cyber systems. it is especially beneficial when the target system is still in development when designers can readily affect improvements. This paper discusses the red team analysis process and the author's experiences applying this process to five selected Information Technology Office (ITO) projects. Some detail of the overall methodology, summary results from the five projects, and lessons learned are contained within this paper.
Date:
November 11, 1999
Creator:
Allerman, Andrew A.; Jones, Eric D.; Kaplar, Robert J.; Kurtz, Steven R.; Kwon, Daewon & Ringel, Steven A.
Object Type:
Article
System:
The UNT Digital Library
Antiprotons and the Crystal Ball
During the 1998 running of the Crystal Ball experiment, a couple of brief test runs were done with the C6 beamline tuned to produce antiprotons. Specifically, one shift on July 29th produced runs 329-334 with the beam momentum set for 650 MeV/c, run 355 was done on July 31st with a 550 MeV/c beam momentum, and run 926-929 were obtained in a single shift on November 3rd, also with a beam momentum of 550 MeV/c. The beam tune for the November data was greatly superior to that of the July data, however. Therefore, only the November data have been analyzed in detail, and the results of this analysis are presented in this note. Due to the paucity of statistics that were obtained, it was decided not to attempt to publish the results. However, the results are valuable as a tool for planning a possible future program of dedicated measurements of antiproton-proton annihilation into all-neutral final states using the Crystal Ball. The data in fact show that the Crystal Ball with its large angular acceptance and multi-photon capability would be an excellent detector for such an experiment. Only one other such experiment (the Crystal Barrel experiment at CERN/LEAR) has ever been …
Date:
November 15, 1999
Creator:
Allgower, C. & Peaslee, D.
Object Type:
Report
System:
The UNT Digital Library
Increased Oil Production and Reserves Utilizing Secondary/Tertiary Recovery Techniques on Small Reservoirs in the Paradox Basin, Utah
The primary objective of this project is to enhance domestic petroleum production by demonstration and technology transfer of an advanced oil recovery technology in the Paradox basin, southeastern Utah. If this project can demonstrate technical and economic feasibility, the technique can be applied to about 100 additional small fields in the Paradox basin alone, and result in increased recovery of 150 to 200 million bbl of oil. This project is designed to characterize five shallow-shelf carbonate reservoirs in the Pennsylvanian (Desmoinesian) Paradox Formation and choose the best candidate for a pilot demonstration project for either a waterflood or carbon dioxide-(CO-) flood 2 project. The field demonstration, monitoring of field performance, and associated validation activities will take place in the Paradox basin within the Navajo Nation. The results of this project will be transferred to industry and other researchers through a petroleum extension service, creation of digital databases for distribution, technical workshops and seminars, field trips, technical presentations at national and regional professional meetings, and publication in newsletters and various technical or trade journals.
Date:
November 3, 1999
Creator:
Allison, M. Lee & Chidsey, Thomas, Jr.
Object Type:
Report
System:
The UNT Digital Library