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A 3-Dimensional discrete fracture network generator to examine fracture-matrix interaction using TOUGH2

Description: Water fluxes in unsaturated, fractured rock involve the physical processes occurring at fracture-matrix interfaces within fracture networks. Modeling these water fluxes using a discrete fracture network model is a complicated effort. Existing preprocessors for TOUGH2 are not suitable to generate grids for fracture networks with various orientations and inclinations. There are several 3-D discrete-fracture-network simulators for flow and transport, but most of them do not capture fracture-matrix interaction. We have developed a new 3-D discrete-fracture-network mesh generator, FRACMESH, to provide TOUGH2 with information about the fracture network configuration and fracture-matrix interactions. FRACMESH transforms a discrete fracture network into a 3 dimensional uniform mesh, in which fractures are considered as elements with unique rock material properties and connected to surrounding matrix elements. Using FRACMESH, individual fractures may have uniform or random aperture distributions to consider heterogeneity. Fracture element volumes and interfacial areas are calculated from fracture geometry within individual elements. By using FRACMESH and TOUGH2, fractures with various inclinations and orientations, and fracture-matrix interaction, can be incorporated. In this paper, results of flow and transport simulations in a fractured rock block utilizing FRACMESH are presented.
Date: April 9, 2003
Creator: Ito, Kazumasa & Yongkoo, Seol
Partner: UNT Libraries Government Documents Department
open access

8-oxoguainine enhances bending of DNA that favors binding of glycosylases

Description: Molecular dynamics (MD) simulations were carried out on the DNA oligonucleotide GGGAACAACTAG:CTAGTTGTTCCC in its native form and with guanine in the central G19:C6 base pair replaced by 8-oxoguanine (8oxoG). A box of explicit water molecules was used for solvation and Na+ counterions were added to neutralize the system. The direction and magnitude of global bending were assessed by a technique used previously to analyze simulations of DNA containing a thymine dimer. The presence of 8oxoG did not greatly affect the magnitude of DNA bending; however, bending into the major groove was significantly more probable when 8oxoG replaced G19. Crystal structures of glycosylases bound to damaged-DNA substrates consistently show a sharp bend into the major groove at the damage site. We conclude that changes in bending dynamics that assist the formation of this kink are a part of the mechanism by which glycosylases of the base excision repair pathway recognize the presence of 8oxoG in DNA.
Date: April 23, 2003
Creator: Miller, John H.
Partner: UNT Libraries Government Documents Department
captions transcript

9-11 Commission Hearing #1, April 1, 2003, Part 1

Description: Recording of the first public hearing held by the National Commission on Terrorist Attacks upon the United States on April 1, 2003 at the Alexander Hamilton U.S. Custom House. This hearing specifically addresses the topics of borders, money, and transportation; law enforcement, domestic intelligence, and homeland security; and immediate response to the attacks. This section includes testimony on the topic of borders, money, and transportation security from representatives of the U.S. Department of Justice, Boies, Schiller, & Flexner LLP, and the U.S. General Accounting Office. It also includes a question and answer session.
Date: April 1, 2003
Duration: 1 hour 2 minutes 31 seconds
Creator: National Commission on Terrorist Attacks upon the United States
Partner: UNT Libraries Government Documents Department
captions transcript

9-11 Commission Hearing #1, April 1, 2003, Part 3

Description: Recording of the first public hearing held by the National Commission on Terrorist Attacks upon the United States on April 1, 2003 at the Alexander Hamilton U.S. Custom House in New York City.This hearing specifically addresses the topics of borders, money, and transportation; law enforcement, domestic intelligence, and homeland security; and immediate response to the attacks. This section includes testimony from representatives of RAND, the Markle Foundation, and the ANSER Institute on the topic of law enforcement, domestic intelligence, and homeland security, in addition to a question and answer session.
Date: April 1, 2003
Duration: 1 hour 2 minutes 43 seconds
Creator: National Commission on Terrorist Attacks upon the United States
Partner: UNT Libraries Government Documents Department
captions transcript

9-11 Commission Hearing #1, April 1, 2003, Part 4

Description: Recording of the first public hearing held by the National Commission on Terrorist Attacks upon the United States on April 1, 2003 at the Alexander Hamilton U.S. Custom House in New York City.This hearing specifically addresses the topics of borders, money, and transportation; law enforcement, domestic intelligence, and homeland security; and immediate response to the attacks. This section includes the question and answer session on law enforcement, domestic intelligence, and homeland security.
Date: April 1, 2003
Duration: 34 minutes 02 seconds
Creator: National Commission on Terrorist Attacks upon the United States
Partner: UNT Libraries Government Documents Department
captions transcript

9-11 Commission Hearing #1, April 1, 2003, Part 5

Description: Recording of the first public hearing held by the National Commission on Terrorist Attacks upon the United States on April 1, 2003 at the Alexander Hamilton U.S. Custom House in New York City.This hearing specifically addresses the topics of borders, money, and transportation; law enforcement, domestic intelligence, and homeland security; and immediate response to the attacks.This section begins the testimony from representatives of the Arlington County Fire Department, the American Society of Civil Engineers, and the New York Department of Design and Construction on the topic of immediate response to the 9/11 attacks.
Date: April 1, 2003
Duration: 11 minutes 42 seconds
Creator: National Commission on Terrorist Attacks upon the United States
Partner: UNT Libraries Government Documents Department
captions transcript

9-11 Commission Hearing #1, April 1, 2003, Part 6

Description: Recording of the first public hearing held by the National Commission on Terrorist Attacks upon the United States on April 1, 2003 at the Alexander Hamilton U.S. Custom House in New York City.This hearing specifically addresses the topics of borders, money, and transportation; law enforcement, domestic intelligence, and homeland security; and immediate response to the attacks.This section continues the question and answer session on the topic of the immediate response to the attacks.
Date: April 1, 2003
Duration: 2 minutes 26 seconds
Creator: National Commission on Terrorist Attacks upon the United States
Partner: UNT Libraries Government Documents Department
captions transcript

9-11 Commission Hearing #3, July 9, 2003, Part 2

Description: Recording of the third public hearing held by the National Commission on Terrorist Attacks upon the United States on July 9, 2003 at the Russell Senate Office Building in Washington, D.C. The one-day session focused on "Terrorism, al Qaeda, and the Muslim World." This section includes the second panel on States and Terrorism, and the third panel on The Challenge within the Muslim World with testimony from experts on transnational terrorism.
Date: April 1, 2003
Duration:
Creator: National Commission on Terrorist Attacks upon the United States
Partner: UNT Libraries Government Documents Department
open access

16-APR-03 Final Release of ENDF/B-V for use with LLNL Codes

Description: The new data files were prepared in two steps. First, the ENDF/B-V database was translated to an ENDL-format ascii database. The ENDL ascii format is a point-wise tabular storage scheme where intermediate values are extracted via interpolation. Sufficient point-wise information was generated in the translation to insure an extraction tolerance of 0.1% for most of the data. The only exception is along the incident neutron energy axis of the outgoing particle energy probability density function where a 0.5% tolerance was maintained. Second, processed files were generated from the translated database. Since the translated ENDF/B-V data is in ENDL-format, the standard processing codes were used to generate the new processed data files. To the best of our knowledge, these processed data files are accurate representations of the ENDF/B-V database to within the stated tolerances. However, there are several issues that users must be aware of and they are listed in this report.
Date: April 16, 2003
Creator: Hill, T S; McNabb, D P; Hedstrom, G W; Beck, B & Hagmann, C A
Partner: UNT Libraries Government Documents Department
open access

AN-102 Simulant Sr/TRU Precipitation and Ultrafiltration

Description: The objective of these tests was to gather data on performance of the single-tube crossflow ultrafilter unit to de-water the simulant precipitate derived from a project approved tank 241-AN-102 simulant. Upon completion of the objectives with the approved R1 simulant, the simulant specification was changed and additional work at modified precipitation conditions was requested.
Date: April 28, 2003
Creator: Zamecnik, J. R.
Partner: UNT Libraries Government Documents Department

[2003 World Dance Alliance V General Assembly of The Americas attendees dance at closing ceremony dinner]

Description: Photograph of attendees of the 2003 World Dance Alliance V General Assembly of The Americas dancing at the closing ceremony dinner. The dinner venue was the Museum of the Royal Houses (Museo de las Casas Reales) in the Dominican Republic.
Date: April 26, 2003
Creator: World Dance Alliance
Partner: UNT Libraries Special Collections

[3rd annual "First Ladies Luncheon" tape 1 of 2]

Description: Video recording from The Black Academy of Arts and Letters recorded during the 3rd annual "First Ladies Luncheon" held on April 12th, 2003. The lunch was held to recognize the wives of Dallas/Fort Worth area religious leaders for their work in supporting the Academy. The footage shows various speakers addressing a room of well-dressed women.
Date: April 12, 2003
Duration: 1 hour 34 minutes 05 seconds
Partner: UNT Libraries Special Collections

[6th Annual Miss Dragonfly]

Description: Photograph of the winner of the sixth annual Miss Dragonfly Pageant. They are standing on stage and are wearing a and gold-detailed dress. They are holding a large bouquet of roses and have a blue sash and tiara on. The audience is visible in front of them.
Date: April 5, 2003
Partner: UNT Libraries Special Collections

[6th Annual Miss Dragonfly court]

Description: Photograph of the winner of the sixth annual Miss Dragonfly Pageant and other contestants. They are gathered on stage and are wearing outfits and evening gowns. The winner is sitting on their throne and have a tiara and sash on. Other contestants are standing behind them in a line and the host is to the side.
Date: April 5, 2003
Partner: UNT Libraries Special Collections

[6th Annual Miss Dragonfly winner and court]

Description: Photograph of the winner of the sixth annual Miss Dragonfly Pageant and other contestants. They are gathered on stage and are wearing outfits and evening gowns. The winner is sitting on their throne and have a tiara and sash on. Other contestants are standing behind them.
Date: April 5, 2003
Partner: UNT Libraries Special Collections

[6th Miss Dragonfly Pageant contestant]

Description: Photograph of the back of a contestant from the sixth annual Miss Dragonfly pageant. They are standing on the edge of the stage and are wearing a gown decorated with rhinestones and matching gloves. Members of the audience are visible past them.
Date: April 5, 2003
Partner: UNT Libraries Special Collections
open access

Abu Sayyaf: Target of Philippine-U.S. Anti-Terrorism Cooperation

Description: This report provides an overview and policy analysis of the Abu Sayyaf terrorist group in the Philippines and the Philippine-U.S. program of military cooperation against it. It examines the origins and operations of Abu Sayyaf, the efforts of the Philippine government and military to eliminate it, and the implications of a greater U.S. military role in attempts to suppress it.
Date: April 8, 2003
Creator: Niksch, Larry
Partner: UNT Libraries Government Documents Department
open access

Accelerator Based Neutron Beams for Neutron Capture Therapy

Description: The DOE-funded accelerator BNCT program at the Massachusetts Institute of Technology has resulted in the only operating accelerator-based epithermal neutron beam facility capable of generating significant dose rates in the world. With five separate beamlines and two different epithermal neutron beam assemblies installed, we are currently capable of treating patients with rheumatoid arthritis in less than 15 minutes (knee joints) or 4 minutes (finger joints) or irradiating patients with shallow brain tumors to a healthy tissue dose of 12.6 Gy in 3.6 hours. The accelerator, designed by Newton scientific Incorporated, is located in dedicated laboratory space that MIT renovated specifically for this project. The Laboratory for Accelerator Beam Applications consists of an accelerator room, a control room, a shielded radiation vault, and additional laboratory space nearby. In addition to the design, construction and characterization of the tandem electrostatic accelerator, this program also resulted in other significant accomplishments. Assemblies for generating epithermal neutron beams were designed, constructed and experimentally evaluated using mixed-field dosimetry techniques. Strategies for target construction and target cooling were implemented and tested. We demonstrated that the method of submerged jet impingement using water as the coolant is capable of handling power densities of up to 6 x 10(sup 7) W/m(sup 2) with heat transfer coefficients of 10(sup 6)W/m(sup 2)-K. Experiments with the liquid metal gallium demonstrated its superiority compared with water with little effect on the neutronic properties of the epithermal beam. Monoenergetic proton beams generated using the accelerator were used to evaluate proton RBE as a function of LET and demonstrated a maximum RBE at approximately 30-40 keV/um, a finding consistent with results published by other researchers. We also developed an experimental approach to biological intercomparison of epithermal beams and compared the RBE characteristics of the MIT Reactor M67 clinical beam, The Brookhaven Medical Research Reactor clinical …
Date: April 11, 2003
Creator: Yanch, Jacquelyn C.
Partner: UNT Libraries Government Documents Department
open access

Accurate Synchronization Between Short Laser Pulse and Electron Bunch by Using HGHG Output at 266nm as Photocathode Laser for RF Gun.

Description: Synchronization between seed laser pulse and electron bunch to below 50 fs is a critically important issue in carrying out cascading HGHG stages to achieve intense temporally coherent x-ray FEL. The single stage HGHG experiment in the IR and recently in UV region has achieved significant success. Hence the next step, to demonstrate the cascading of 2 stages of HGHG becomes crucially important in confirming the viability of this scheme. Based on our experiences at DUVFEL during the HGHG experiment, we can measure the time jitter between the electron bunch and the RF phase before compression to a high precision of order of 50 fs. Without the compression, this is equal to the time jitter between the laser and the RF phase. An analysis of this measurement suggests that it is possible to use a fast feedback system to reduce the jitter significantly. However, during the successful HGHG experiment at 266 nm recently, we realized that there is a simpler way to achieve highly accurate synchronization. Here we describe the method.
Date: April 1, 2003
Creator: Yu, L. H.
Partner: UNT Libraries Government Documents Department
open access

ACHIEVING NEW SOURCE PERFORMANCE STANDARDS (NSPS) EMISSION STANDARDS THROUGH INTEGRATION OF LOW-NOx BURNERS WITH AN OPTIMIZATION PLAN FOR BOILER COMBUSTION

Description: The objective of this project is to demonstrate the use of an Integrated Combustion Optimization System to achieve NO{sub x} emissions levels in the range of 0.15 to 0.22 lb/MMBtu while simultaneously enabling increased power output. The project consists of the integration of low-NO{sub x} burners and advanced overfire air technology with various process measurement and control devices on the Holcomb Station Unit 1 boiler. The project includes the use of sophisticated neural networks or other artificial intelligence technologies and complex software that can optimize several operating parameters, including NO{sub x} emissions, boiler efficiency, and CO emissions. The program is being performed in three phases. In Phase I, the boiler is being equipped with sensors that can be used to monitor furnace conditions and coal flow to permit improvements in boiler operation. In Phase II, the boiler will be equipped with burner modifications designed to reduce NO{sub x} emissions and automated coal flow dampers to permit on-line fuel balancing. In Phase III, the boiler will be equipped with an overfire air system to permit deep reductions in NO{sub x} emissions to be achieved. Integration of the overfire air system with the improvements made in Phases I and II will permit optimization of the boiler performance, output, and emissions. During this reporting period, efforts were focused on Phase I and Phase II activities. The furnace sensors were procured and installed in February 2003. Baseline testing was performed following the sensor installation. The low-NO{sub x} burner modifications, the coal flow dampers, and the coal flow monitoring system were procured and installed during a boiler outage in March 2003. Process design activities were performed to support design of the equipment installed and to develop specifications for the overfire air system. The overfire air system preliminary engineering design was initiated.
Date: April 1, 2003
Creator: Penrod, Wayne & Moyeda, David
Partner: UNT Libraries Government Documents Department
open access

Acoustic Detecting and Locating Gas Pipe Line Infringement Quarterly Report: Number 3

Description: The West Virginia University natural gas transmission line leak detection research is only considering using readily available 1/2 inch pipeline access ports for the detection of leak generated signals. The main problem with leak signals is the low signal to noise ratio. One of the acoustic signals associated with gas escaping through a leak is only temporary and is in the form of a rarefaction wave originating when the leak is formed. Due to pipeline friction, over distance such a step function transitions to a ramp function. The ability to identify a leak by pipeline monitoring and signal processing depends a great deal on the quality and signal to noise ratio of the characteristics of the detectors used. Combinations of sensing devices are being used for the WVU sensor package and are contained in a removable sensor housing. The four sensors currently installed are a 1/2 inch 3 Hz-40 Khz microphone, an audible range moving coil sensor, a piezo-electric pressure transducer, and the WVU designed floating 3 inch diameter diaphragm to detect flow transient induced pressure ramp type signals. The WVU diaphragm sensor, which is currently under development, uses the same diaphragm principle as a high quality capacitance type microphone, but utilizes aerodynamic signal amplification. This type of amplification only amplifies the ramp-signal itself, not the random pipeline noise.
Date: April 1, 2003
Creator: Loth, John L.; Morris, Gary J.; Palmer, George M.; Guiler, Richard & Mehra, Deepak
Partner: UNT Libraries Government Documents Department
open access

Active Cathodes for Super-High Power Density Solid Oxide Fuel Cells Through Space Charge Effects Quarterly Report: October 2002 - January 2003

Description: This report summarizes the work done during the first quarter of the project. Effort was directed in three areas: (1) The determination of the role of ionic conductor morphology, used in composite cathodes, on the ionic conductivity of the ionic conductor. It was shown that if the particles are not well sintered, the necks formed between particles will be very narrow, and the resulting conductivity will be too low (resistivity will be too high). Specifically, a mathematical equation was derived to demonstrate the singular nature of conductivity. (2) Nanosize powders of Sc-doped CeO{sub 2} were prepared by combustion synthesis. The rationale is that the particle size of the composite electrode must be as small as possible to ensure a high ionic conductivity--and resulting in high performance in fuel cells. Di-gluconic acid (DGA) was used as fuel. The process led to the formation of nanosize Sc-doped CeO{sub 2}. The powder was characterized by X-ray diffraction (XRD) and transmission electron microscopy (TEM). (3) Samples were sintered to form materials containing various levels of porosity, from {approx}3% to {approx}43%. Conductivity was measured over a range of temperatures by four probe DC method. It was observed that in highly porous samples, the conductivity was far lower than can be expected purely based on total porosity. The difference could be rationalized on the basis of the theoretical model developed.
Date: April 14, 2003
Creator: Virkar, Professor Anil V.
Partner: UNT Libraries Government Documents Department
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