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A 1-Joule laser for a 16-fiber injection system (open access)

A 1-Joule laser for a 16-fiber injection system

A 1-J laser was designed to launch light down 16, multi-mode fibers (400-{micro}m-core dia.). A diffractive-optic splitter was designed in collaboration with Digital Optics Corporation (DOC), and was delivered by DOC. Using this splitter, the energy injected into each fiber varied <1%. The spatial profile out of each fiber was such that there were no ''hot spots,'' a flyer could successfully be launched and a PETN pellet could be initiated. Preliminary designs of the system were driven by system efficiency where a pristine TEM{sub 00} laser beam would be required. The laser is a master oscillator, power amplifier (MOPA) consisting of a 4-mm-dia. Nd:YLF rod in the stable, q-switched oscillator and a 9.5-mm-dia. Nd:YLF rod in the double-passed amplifier. Using a TEM{sub 00} oscillator beam resulted in excellent transmission efficiencies through the fibers at lower energies but proved to be quite unreliable at higher energies, causing premature fiber damage, flyer plate rupture, stimulated Raman scattering (SRS), and stimulated Brillouin scattering (SBS). Upon further investigation, it was found that both temporal and spatial beam formatting of the laser were required to successfully initiate the PETN. Results from the single-mode experiments, including fiber damage, SRS and SBS losses, will be presented. In …
Date: April 6, 2004
Creator: Honig, J.
Object Type: Article
System: The UNT Digital Library
1+ -n+ ECR Ion Source Development Test Stand (open access)

1+ -n+ ECR Ion Source Development Test Stand

A test stand for the investigation of 1+-n+ charge boosting using an ECR ion sources is currently being assembled at the Texas A&M Cyclotron Institute. The ultimate goal is to relate the charge-boosting of ions of stable species to possible charge-boosting of ions of radioactive species extracted from the diverse, low-charge-state ion sources developed for radioactive ion beams.
Date: April 7, 2006
Creator: May, Donald P.
Object Type: Report
System: The UNT Digital Library
2\beta + \gamma from B^0 to D^\mp K^0 \pi^\pm Decays at BaBar: aSimulation Study (open access)

2\beta + \gamma from B^0 to D^\mp K^0 \pi^\pm Decays at BaBar: aSimulation Study

The authors present the results of a simulation study to perform the extraction of 2{beta} + {gamma} from B{sup 0} {yields} D{sup {-+}}K{sup 0}{pi}{sup {+-}} decays through a time-dependent Dalitz analysis of BaBar data.
Date: April 16, 2007
Creator: Polci, Francesco; Schune, Marie-Helene; Stocchi, Achille & /Orsay, LAL
Object Type: Article
System: The UNT Digital Library
2-D and 3-D Elastic Modeling with Shared Seismic Models (open access)

2-D and 3-D Elastic Modeling with Shared Seismic Models

Several elastic models, both 2-D and 3-D, are being built for use in calculating synthetic elastic seismic data. The models will be made available to the research community, along with the synthetic data that are being calculated from them. These shared models have been proposed or contributed by participants in a collaborative industry, national laboratory, and university research project. The purpose of the modeling is to provide synthetic data to better understand elastic wave propagation and the effects of structural and stratigraphic complexities. The 2-D models are easier to design and change and synthetic calculations can be run relatively quickly in them. It will be possible to alter their layer properties and calculate time-lapse data sets from them. Field data will be available to accompany many of the 2-D models. 3-D models are more realistic, but more difficult to design and change. They also require considerably more computing resources to calculate synthetic data from them. A new 3-D model is being designed, and will be used for computing synthetic elastic data.
Date: April 30, 2002
Creator: House, L.; Marfurt, K. J.; Larsen, S. & Martin, G. S.
Object Type: Article
System: The UNT Digital Library
3-D elastic wave scattering by a layer containing vertical periodic fractures (open access)

3-D elastic wave scattering by a layer containing vertical periodic fractures

None
Date: April 30, 2002
Creator: Nakagawa, Seiji; Nihei, Kurt T.; Myer, Larry R. & Majer, Ernest L.
Object Type: Article
System: The UNT Digital Library
A 3-D Model of Signaling and Transport Pathways in Epithelial Cells (open access)

A 3-D Model of Signaling and Transport Pathways in Epithelial Cells

A 3-dimensional computer model was developed to simulate the spatial and chemical evolution of calcium ions inside an array of human epithelial kidney cells. This is a prototype model, intended to develop a methodology to incorporate much more complex interactions of metabolic and other processes within many types of cells and lead to increased ability to predict cellular responses to disease as well as to chemical and biological warfare situations. Preliminary tests of the model are described.
Date: April 1, 2005
Creator: Quong, Andrew A. & Westbrook, Charles K.
Object Type: Report
System: The UNT Digital Library
A 3-Dimensional discrete fracture network generator to examine fracture-matrix interaction using TOUGH2 (open access)

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

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
Object Type: Article
System: The UNT Digital Library
8-oxoguainine enhances bending of DNA that favors binding of glycosylases (open access)

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

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.
Object Type: Article
System: The UNT Digital Library
9-11 Commission Hearing #1, April 1, 2003, Part 1 captions transcript

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

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
Creator: National Commission on Terrorist Attacks upon the United States
Object Type: Video
System: The UNT Digital Library
9-11 Commission Hearing #1, April 1, 2003, Part 2 captions transcript

9-11 Commission Hearing #1, April 1, 2003, Part 2

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 Steven Brill on the subject of law enforcement, domestic intelligence, and homeland security.
Date: April 1, 2004
Creator: National Commission on Terrorist Attacks upon the United States
Object Type: Video
System: The UNT Digital Library
9-11 Commission Hearing #1, April 1, 2003, Part 3 captions transcript

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

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
Creator: National Commission on Terrorist Attacks upon the United States
Object Type: Video
System: The UNT Digital Library
9-11 Commission Hearing #1, April 1, 2003, Part 4 captions transcript

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

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
Creator: National Commission on Terrorist Attacks upon the United States
Object Type: Video
System: The UNT Digital Library
9-11 Commission Hearing #1, April 1, 2003, Part 5 captions transcript

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

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
Creator: National Commission on Terrorist Attacks upon the United States
Object Type: Video
System: The UNT Digital Library
9-11 Commission Hearing #1, April 1, 2003, Part 6 captions transcript

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

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
Creator: National Commission on Terrorist Attacks upon the United States
Object Type: Video
System: The UNT Digital Library
9-11 Commission Hearing #3, July 9, 2003, Part 2 captions transcript

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

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
Creator: National Commission on Terrorist Attacks upon the United States
Object Type: Video
System: The UNT Digital Library
9-11 Commission Hearing #9, April 8, 2004, Part 1 captions transcript

9-11 Commission Hearing #9, April 8, 2004, Part 1

Recording of the ninth public hearing held by the National Commission on Terrorist Attacks upon the United States on April 8, 2004 at the Hart Senate Office Building in Washington, D.C. The Commission heard testimony from Dr. Condoleezza Rice, Assistant to the President for National Security Affairs on the formulation and conduct of U.S. counterterrorism policy.
Date: April 8, 2004
Creator: National Commission on Terrorist Attacks upon the United States
Object Type: Video
System: The UNT Digital Library
9-11 Commission Hearing #10, April 13, 2004, Part 1 captions transcript

9-11 Commission Hearing #10, April 13, 2004, Part 1

Recording of the tenth public hearing held by the National Commission on Terrorist Attacks upon the United States on April 13, 2004 in Washington, D.C. The two-day hearing examined the performance of law enforcement and the Intelligence Community prior to September 11 and evaluated post-9/11 reforms in these areas. In addition to witness testimony, four staff statements were delivered during the course of the proceedings. This section includes the opening statement by Chairman Kean, in addition to the staff statement on law enforcement, counterterrorism, and intelligence collection in the United States prior to 9/11, and the first panel with testimony from Louis J. Freeh.
Date: April 13, 2004
Creator: National Commission on Terrorist Attacks upon the United States
Object Type: Video
System: The UNT Digital Library
9-11 Commission Hearing #10, April 13, 2004, Part 2 captions transcript

9-11 Commission Hearing #10, April 13, 2004, Part 2

Recording of the tenth public hearing held by the National Commission on Terrorist Attacks upon the United States on April 13, 2004 in Washington, D.C. The two-day hearing examined the performance of law enforcement and the Intelligence Community prior to September 11 and evaluated post-9/11 reforms in these areas. In addition to witness testimony, four staff statements were delivered during the course of the proceedings.This section includes the second panel of the hearing with testimony from former Attorney General, Janet Reno.
Date: April 13, 2004
Creator: National Commission on Terrorist Attacks upon the United States
Object Type: Video
System: The UNT Digital Library
9-11 Commission Hearing #10, April 13, 2004, Part 3 captions transcript

9-11 Commission Hearing #10, April 13, 2004, Part 3

Recording of the tenth public hearing held by the National Commission on Terrorist Attacks upon the United States on April 13, 2004 in Washington, D.C. The two-day hearing examined the performance of law enforcement and the Intelligence Community prior to September 11 and evaluated post-9/11 reforms in these areas. In addition to witness testimony, four staff statements were delivered during the course of the proceedings. This section includes the staff statement on threats and responses in 2001 in addition to the third panel on Summer 2001, with testimony from Thomas J. Pickard and J. Cofer Black.
Date: April 13, 2004
Creator: National Commission on Terrorist Attacks upon the United States
Object Type: Video
System: The UNT Digital Library
9-11 Commission Hearing #10, April 13, 2004, Part 4 captions transcript

9-11 Commission Hearing #10, April 13, 2004, Part 4

Recording of the tenth public hearing held by the National Commission on Terrorist Attacks upon the United States on April 13, 2004 in Washington, D.C. The two-day hearing examined the performance of law enforcement and the Intelligence Community prior to September 11 and evaluated post-9/11 reforms in these areas. In addition to witness testimony, four staff statements were delivered during the course of the proceedings. This section includes the panel on Summer 2001 with testimony by John Ashcroft, Attorney General of the United States.
Date: April 13, 2004
Creator: National Commission on Terrorist Attacks upon the United States
Object Type: Video
System: The UNT Digital Library
9-11 Commission Hearing #10, April 14, 2004, Part 1 captions transcript

9-11 Commission Hearing #10, April 14, 2004, Part 1

Recording of the tenth public hearing held by the National Commission on Terrorist Attacks upon the United States on April 14, 2004 in Washington, D.C. The two-day hearing examined the performance of law enforcement and the Intelligence Community prior to September 11 and evaluated post-9/11 reforms in these areas. In addition to witness testimony, four staff statements were delivered during the course of the proceedings. This section includes the staff statement on the performance of the intelligence community in addition to the panel on Summer 2001 with testimony from George J. Tenet.
Date: April 14, 2004
Creator: National Commission on Terrorist Attacks upon the United States
Object Type: Video
System: The UNT Digital Library
9-11 Commission Hearing #10, April 14, 2004, Part 2 captions transcript

9-11 Commission Hearing #10, April 14, 2004, Part 2

Recording of the tenth public hearing held by the National Commission on Terrorist Attacks upon the United States on April 14, 2004 in Washington, D.C. The two-day hearing examined the performance of law enforcement and the Intelligence Community prior to September 11 and evaluated post-9/11 reforms in these areas. In addition to witness testimony, four staff statements were delivered during the course of the proceedings. This section includes the panel on preventing future attacks inside the United States, with testimony from John O. Brennan, Lieutenant General Patrick M. Hughes, John S. Pistole, and James L. Pavitt.
Date: April 14, 2004
Creator: National Commission on Terrorist Attacks upon the United States
Object Type: Video
System: The UNT Digital Library
9-11 Commission Hearing #10, April 14, 2004, Part 3 captions transcript

9-11 Commission Hearing #10, April 14, 2004, Part 3

Recording of the tenth public hearing held by the National Commission on Terrorist Attacks upon the United States on April 14, 2004 in Washington, D.C. The two-day hearing examined the performance of law enforcement and the Intelligence Community prior to September 11 and evaluated post-9/11 reforms in these areas. In addition to witness testimony, four staff statements were delivered during the course of the proceedings. This section includes the staff statement on reforming law enforcement, counterterrorism, and intelligence collection in the United States, in addition to the panel on FBI leadership and initiatives post 9/11 with testimony from Robert S. Muller.
Date: April 14, 2004
Creator: National Commission on Terrorist Attacks upon the United States
Object Type: Video
System: The UNT Digital Library
12.6 keV Kr K-alpha X-ray Source For High Energy Density Physics Experiments (open access)

12.6 keV Kr K-alpha X-ray Source For High Energy Density Physics Experiments

A high contrast 12.6 keV Kr K{alpha} source has been demonstrated on the petawatt-class Titan laser facility. The contrast ratio (K{alpha} to continuum) is 65, with a competitive ultra short pulse laser to x-ray conversion efficiency of 10{sup -5}. Filtered shadowgraphy indicates that the Kr K{alpha} and K{beta} x-rays are emitted from a roughly 1 x 2 mm emission volume, making this source suitable for area backlighting and scattering. Spectral calculations indicate a typical bulk electron temperature of 50-70 eV (i.e. mean ionization state 13-16), based on the observed ratio of K{alpha} to K{beta}. Kr gas jets provide a debris-free high energy K{alpha} source for time-resolved diagnosis of dense matter.
Date: April 22, 2008
Creator: Kugland, N.; Constantin, C. G.; Niemann, C.; Neumayer, P.; Chung, H.; Doppner, T. et al.
Object Type: Article
System: The UNT Digital Library