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Comments on Worldsheet Theories Dual to Free Large N Gauge Theories (open access)

Comments on Worldsheet Theories Dual to Free Large N Gauge Theories

We continue to investigate properties of the worldsheet conformal field theories (CFTs) which are conjectured to be dual to free large N gauge theories, using the mapping of Feynman diagrams to the worldsheet suggested in [1]. The modular invariance of these CFTs is shown to be built into the formalism. We show that correlation functions in these CFTs which are localized on subspaces of the moduli space may be interpreted as delta-function distributions, and that this can be consistent with a local worldsheet description given some constraints on the operator product expansion coefficients. We illustrate these features by a detailed analysis of a specific four-point function diagram. To reliably compute this correlator we use a novel perturbation scheme which involves an expansion in the large dimension of some operators.
Date: March 21, 2007
Creator: Aharony, Ofer; /Weizmann Inst. /Stanford U., ITP /SLAC; David, Justin R.; Gopakumar, Rajesh; Inst., /Harish-Chandra Res.; Komargodski, Zohar et al.
System: The UNT Digital Library
The Moduli Space and M(Atrix) Theory of 9d N=1 Backgrounds of M/String Theory (open access)

The Moduli Space and M(Atrix) Theory of 9d N=1 Backgrounds of M/String Theory

We discuss the moduli space of nine dimensional N = 1 supersymmetric compactifications of M theory/string theory with reduced rank (rank 10 or rank 2), exhibiting how all the different theories (including M theory compactified on a Klein bottle and on a Moebius strip, the Dabholkar-Park background, CHL strings and asymmetric orbifolds of type II strings on a circle) fit together, and what are the weakly coupled descriptions in different regions of the moduli space. We argue that there are two disconnected components in the moduli space of theories with rank 2. We analyze in detail the limits of the M theory compactifications on a Klein bottle and on a Moebius strip which naively give type IIA string theory with an uncharged orientifold 8-plane carrying discrete RR flux. In order to consistently describe these limits we conjecture that this orientifold non-perturbatively splits into a D8-brane and an orientifold plane of charge (-1) which sits at infinite coupling. We construct the M(atrix) theory for M theory on a Klein bottle (and the theories related to it), which is given by a 2 + 1 dimensional gauge theory with a varying gauge coupling compactified on a cylinder with specific boundary conditions. We …
Date: March 21, 2007
Creator: Aharony, Ofer; /Weizmann Inst. /Stanford U., ITP /SLAC; Komargodski, Zohar; Patir, Assaf & Inst., /Weizmann
System: The UNT Digital Library
U.S.-European Union Trade Relations: Issues and Policy Challenges (open access)

U.S.-European Union Trade Relations: Issues and Policy Challenges

None
Date: March 21, 2003
Creator: Ahearn, Raymond J.
System: The UNT Digital Library
Chemical Depth Profiling from Neutron Reflectometry (open access)

Chemical Depth Profiling from Neutron Reflectometry

The material profile of a thin film can be analyzed by placing the film on a substrate and by sending a neutron beam onto it at various angles of incidence. Technically, the scattering length density of the film needs to be determined as a function of depth. A reflectometer is used to measure the amount of reflection (reflectivity) as a function of the angle of incidence. Mathematically, this is equivalent to sending the neutron beam onto the film at every energy but at a fixed angle of incidence. The film profile needs to be recovered from the measured reflectivity data. Unfortunately, the unique recovery is impossible, and many distinct unrelated profiles may correspond to the same reflectivity data. In our DOE/EPSCoR sponsored research, we have developed an analytical method to uniquely recover the profile of a thin film from the measured reflectivity data. We have shown that by taking reflectivity measurements with two different substrates, one can uniquely determine the film profile. Previously, it was known that one could uniquely recover the profile by taking reflectivity measurements with three different substrates, and our findings indicate that the same goal can be accomplished by using fewer measurements. At Mississippi State University …
Date: March 21, 2006
Creator: Aktosun, Tuncay
System: The UNT Digital Library
EARLY ENTRANCE COPRODUCTION PLANT (open access)

EARLY ENTRANCE COPRODUCTION PLANT

As part of the Department of Energy's (DOE) Gasification Technologies and Transportation Fuels and Chemicals programs, DOE and Texaco are partners through Cooperative Agreement DE-FC26-99FT40658 to determine the feasibility of developing, constructing and operating an Early Entrance Coproduction Plant (EECP). The overall objective of the project is the three-phase development of an EECP that produces at least one product from at least two of the following three categories: Electric power (or heat); Fuels; and Chemicals. The objective is to have these products produced by technologies capable of using synthesis gas derived from coal and/or some other carbonaceous feedstock, such as petroleum coke. The objective of Phase I was to determine the feasibility and define the concept for the EECP located at a specific site and to develop a Research, Development, and Testing (RD and T) Plan for implementation in Phase II. This objective has now been accomplished. A specific site, Motiva Refinery in Port Arthur, Texas, has been selected as the location best suited for the EECP. The specific work requirements of Phase I included: Prepare an EECP Preliminary Concept Report covering Tasks 2-8 specified in the Cooperative Agreement; Develop a Research, Development, and Testing (RD and T) Plan as …
Date: March 21, 2001
Creator: Anderson, John H.; Davis, William K. & Sloop, Thomas W.
System: The UNT Digital Library
Distortion Correction for the Many Beam Fabry Perot Velocimeter (open access)

Distortion Correction for the Many Beam Fabry Perot Velocimeter

Graphical curves and text tables are presented that map out time and space distortions for data obtained from film records of the Many Beam Fabry Perot Velocimeter. Effective distortion corrections extracted from these mappings can be applied to upcoming velocimetry experiments, but only with limited success over periods of a year or more into the future. A method of using three fiducials to provide fresh time and space distortion data on each film record is presented as a more reliable procedure to correct distortions to an acceptable level of accuracy.
Date: March 21, 2001
Creator: Avara, G.; Collins, L. & Rivera, A.
System: The UNT Digital Library
Test results of chemical reactivity test (CRT) analysis of structural materials and explosives (open access)

Test results of chemical reactivity test (CRT) analysis of structural materials and explosives

The chemical reactivity test, CRT, is a procedure used to screen the compatibility of component structure materials with explosives. This report contains the results of CRT materials evaluations conducted at Mound Facility. Data about materials combinations are catalogued both under the name of the explosive and the nonexplosive.
Date: March 21, 1980
Creator: Back, Paul S.; Barnhart, Brady V.; Walters, Ronald R.; Haws, Lowell D. & Collins, Louis W.
System: The UNT Digital Library
The Effects of Hydroxylamine on the C14O2 Fixation Pattern During Photosynthesis (open access)

The Effects of Hydroxylamine on the C14O2 Fixation Pattern During Photosynthesis

None
Date: March 21, 1958
Creator: Bassham, J. A.; Kirk, M. & Calvin, M.
System: The UNT Digital Library
The State Children's Health Insurance Program: Eligibility, Enrollment, and Program Funding (open access)

The State Children's Health Insurance Program: Eligibility, Enrollment, and Program Funding

None
Date: March 21, 2001
Creator: Baumrucker, Evelyne P.
System: The UNT Digital Library
Production test authorization: 011 HDS and ALSI fuel performance monitoring (open access)

Production test authorization: 011 HDS and ALSI fuel performance monitoring

Much useful information has been gained from this program, leading to improvements and additions to non-destructive testing equipment, improved fuel quality, and a generally better understanding of fuel performance. The original objectives of the program have been met -- at least to the extent that such information can now be effectively used. However, other aspects of the program have a continuing value. Visual examination and dimensional data obtained routinely on production fuels have been a useful tool as a monitor of reactor conditions and trends, and of fuel quality. This test authorization proposes to continue a PT-216 type of program, modified to better serve today`s needs.
Date: March 21, 1966
Creator: Bears, R.E.
System: The UNT Digital Library
BSE (“Mad Cow Disease”): A Brief Overview (open access)

BSE (“Mad Cow Disease”): A Brief Overview

This report provides background on appearance of BSE(bovine spongiform encephalopathy or "mad cow disease") in North America.
Date: March 21, 2006
Creator: Becker, Geoffrey S.
System: The UNT Digital Library
Energy and Water Development: FY2011 Appropriations (open access)

Energy and Water Development: FY2011 Appropriations

This report covers key budgetary issues involving the Energy and Water Development appropriations bill, which provides funding for civil works projects of the Army Corps of Engineers (Corps), the Department of the Interior’s Bureau of Reclamation, the Department of Energy (DOE), and a number of independent agencies.
Date: March 21, 2011
Creator: Behrens, Carl E.
System: The UNT Digital Library
Energy Policy: 113th Congress Issues (open access)

Energy Policy: 113th Congress Issues

This report discusses the energy policy in the United States that is focused on three major goals: assuring a secure supply of energy, keeping energy costs low, and protecting the environment.
Date: March 21, 2014
Creator: Behrens, Carl E.
System: The UNT Digital Library
Nuclear Nonproliferation Issues (open access)

Nuclear Nonproliferation Issues

None
Date: March 21, 2003
Creator: Behrens, Carl E.
System: The UNT Digital Library
Determination of /sup 232/U daughter products released from HTGR fuel during refabrication. Part 2 (open access)

Determination of /sup 232/U daughter products released from HTGR fuel during refabrication. Part 2

During the heat treatment step of High Temperature Gas-Cooled Reactor (HTGR) fuel beads, the /sup 233/U-loaded fuel beads are exposed to temperatures as high as 1700/sup 0/C. Since /sup 233/U fuel beads unavoidably contain a small percentage of /sup 232/U, decay products of /sup 232/U might be released during the heat treatment step. To avoid shielding requirements, experiments were conducted using /sup 232/Th-loaded fuel beads rather than /sup 232/U-loaded fuel beads. Decay products of /sup 232/U and /sup 232/Th are the same after /sup 228/Th. Experimental data were obtained by monitoring the 583 and 2614 keV gamma emissions of /sup 208/Tl. Computer simulations of the decay process and experimental data were used to infer what relative amount of the daughter products was removed. The carbonization step (300 to 500/sup 0/C) has an effect on the loss of daughter products in the conversion step. Using uncarbonized fuel beads, approximately 50 percent of /sup 220/Rn was removed at 300/sup 0/C and approximately 20 percent of /sup 220/Rn was removed at 200/sup 0/C. At most, 5 percent of /sup 220/Rn was removed from uncarbonized beads at 25/sup 0/C. Marginal /sup 220/Rn loss was detected at 100/sup 0/C using pre-carbonized beads. At 1400/sup 0/C, …
Date: March 21, 1975
Creator: Bencini-Tibo, L. F.; Horton, J. R. & Kelley, D. F.
System: The UNT Digital Library
Systems and economic analysis of microalgae ponds for conversion of CO{sub 2} to biomass. Final report (open access)

Systems and economic analysis of microalgae ponds for conversion of CO{sub 2} to biomass. Final report

There is growing evidence that global warming could become a major global environmental threat during the 21st century. The precautionary principle commands preventive action, at both national and international levels, to minimize this potential threat. Many near-term, relatively inexpensive, mitigation options are available. In addition, long-term research is required to evaluate and develop advanced, possibly more expensive, countermeasures, in the eventuality that they may be required. The utilization of power plant CO{sub 2} and its recycling into fossil fuel substitutes by microalgae cultures could be one such long-term technology. Microalgae production is an expanding industry in the U.S., with three commercial systems (of approximately 10 hectare each) producing nutriceuticals, specifically beta-carotene, extracted from Dunaliella, and Spirulina biomass. Microalgae are also used in wastewater treatment. Currently production costs are high, about $10,000/ton of algal biomass, almost two orders of magnitude higher than acceptable for greenhouse gas mitigation. This report reviews the current state-of-the-art, including algal cultivation and harvesting-processing, and outlines a technique for achieving very high productivities. Costs of CO{sub 2} mitigation with microalgae production of oils ({open_quotes}biodiesel{close_quotes}) are estimated and future R&D needs outlined.
Date: March 21, 1996
Creator: Benemann, John R. & Oswald, William J.
System: The UNT Digital Library
An Equivalent Circuit Model and Power Calculations for the APS SPX Crab Cavities. (open access)

An Equivalent Circuit Model and Power Calculations for the APS SPX Crab Cavities.

An equivalent parallel resistor-inductor-capacitor (RLC) circuit with beam loading for a polarized TM110 dipole-mode cavity is developed and minimum radio-frequency (rf) generator requirements are calculated for the Advanced Photon Source (APS) short-pulse x-ray (SPX) superconducting rf (SRF) crab cavities. A beam-loaded circuit model for polarized TM110 mode crab cavities was derived. The single-cavity minimum steady-state required generator power has been determined for the APS SPX crab cavities for a storage ring current of 200mA DC current as a function of external Q for various vertical offsets including beam tilt and uncontrollable detuning. Calculations to aid machine protection considerations were given.
Date: March 21, 2012
Creator: Berenc, T.
System: The UNT Digital Library
Three methods to measure RH bond energies (open access)

Three methods to measure RH bond energies

In this paper the authors compare and contrast three powerful methods for experimentally measuring bond energies in polyatomic molecules. The methods are: radical kinetics; gas phase acidity cycles; and photoionization mass spectroscopy. The knowledge of the values of bond energies are a basic piece of information to a chemist. Chemical reactions involve the making and breaking of chemical bonds. It has been shown that comparable bonds in polyatomic molecules, compared to the same bonds in radicals, can be significantly different. These bond energies can be measured in terms of bond dissociation energies.
Date: March 21, 1993
Creator: Berkowitz, J.; Ellison, G. B. & Gutman, D.
System: The UNT Digital Library
Survey of Recent Developments in Solvent Extraction With Tributyl Phosphate (open access)

Survey of Recent Developments in Solvent Extraction With Tributyl Phosphate

Tributyl phosphate can be used for extraction in processing all current power reactor fuels. Nitric acid is the only salting agent required. Typical flowsheets are presented. In aluminum nitrate systems which are more than 0.1 M acid deficient, the uranium distribution coefficient is a function of pH and independent of aluminum concentration; the coefficient remains constant at one in fluoride systems when the nitrate to fluoride ratio is approximates 3.5. Many objectionable properties of degraded diluents are ascribed to nitroparaffins. Aliphatic diluents with the least branching are the most stable to nitration. The nitration stability of aromatic diluents varies with structure, e.g., stabilities of diethylbenzenes decrease as meta >> ortho > para. Solvent purification by flash distillation appears superior to other methods. The stability of Amsco 125-82 was permanently improved by treatment with sulfuric acid. The radiation stability of TBP was approximates 2 times higher in an aromatic diluent than in Amsco 125-82. The G decomposition value for 1 M TBP in Amsco alone was approximates 0.9; whereas in 1 to 3 M HNO/sub 3/ it was 1 to 5 and G (--HNO/sub 3/ org phase) was 3 to 20. Variation of uranium--thorium separation factors with structure of some neutral …
Date: March 21, 1963
Creator: Blanco, R. E.; Blake, C. A., Jr.; Davis, W. Jr. & Rainey, R.H.
System: The UNT Digital Library
Partial Acceptance for Beneficial Use (ABU) for the Type 4 In Situ Vapor Sampler (ISVS) Carts (open access)

Partial Acceptance for Beneficial Use (ABU) for the Type 4 In Situ Vapor Sampler (ISVS) Carts

This document provides the ''Partial'' Acceptance for Beneficial Use (ABU), for the Type 4 in-situ vapor sampler system (ISVS). This document is generated to support the completion of equipment modifications and engineering documentation for the ISVS system that is used for sampling gaseous vapors in the Hanford single shell radioactive waste storage tanks. The ABU is used to document the items required for transferring the ISVS system to operations for field use. This document is generated following Characterization Engineering Desk Instruction DI-CE-004-001.
Date: March 21, 2000
Creator: Boger, R. M.
System: The UNT Digital Library
Air Force FB-22 Bomber Concept (open access)

Air Force FB-22 Bomber Concept

The Air Force has expressed interest in developing a bomber variant of the F-22A Raptor to "bridge the gap" between today's bombers and a follow-on bomber in 2037. Questions exist regarding the FB-22's feasibility, cost, and combat potential.
Date: March 21, 2005
Creator: Bolkcom, Christopher
System: The UNT Digital Library
F-22 Aircraft Program (open access)

F-22 Aircraft Program

This report discusses the background information, analysis and the recent developments in the F-22 Aircraft Program. The F-22 program raises questions about its cost and the need for this aircraft, the capabilities it would have, and the number of these planes needed to meet military requirements. The F-22 has had strong congressional support, although some have criticized the program on grounds of cost, requirements, and coordination with other tactical aircraft programs. Deletion of procurement funds in the FY2000 defense appropriation bill passed by the House made the future of the program a major issue for House and Senate conferees in 1999.
Date: March 21, 2000
Creator: Bolkcom, Christopher
System: The UNT Digital Library
F-22 Raptor Aircraft Program (open access)

F-22 Raptor Aircraft Program

None
Date: March 21, 2002
Creator: Bolkcom, Christopher
System: The UNT Digital Library
Nanosecond Ultrasonics to Study Phase Transitions in Solid and Liquid Systems at High Pressure and Temperature (open access)

Nanosecond Ultrasonics to Study Phase Transitions in Solid and Liquid Systems at High Pressure and Temperature

This report describes the development of a high-frequency ultrasonic measurement capability for application to the study of phase transitions at elevated pressure and temperature. We combined expertise in various aspects of static high-pressure technique with recent advances in wave propagation modeling, ultrasonic transducer development, electronic methods and broadband instrumentation to accomplish the goals of this project. The transduction and electronic systems have a demonstrated bandwidth of 400 MHz, allowing investigations of phenomena with characteristic times as short as 2.5 nS. A compact, pneumatically driven moissanite anvil cell was developed and constructed for this project. This device generates a high-pressure environment for mm dimension samples to pressures of 3 GPa. Ultrasonic measurements were conducted in the moissanite cell, an LLNL multi-anvil device and in a modified piston cylinder device. Measurements for water, and elemental tantalum, tin and cerium demonstrate the success of the methods. The {gamma}-{alpha} phase transition in cerium was clearly detected at {approx}0.7 GPa with 75 MHz longitudinal waves. These results have direct application to important problems in LLNL programs, as well as seismology and planetary science.
Date: March 21, 2007
Creator: Bonner, B P; Berge, P A; Carlson, S C; Farber, D L & Akella, J
System: The UNT Digital Library