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Simulation of Alpha-Channeling in Mirror Machines

Description: Applying α-channeling techniques to mirror machines can significantly increase their effective reactivity, thus making open configurations more advantageous for practical fusion. A large fraction of α particle energy can be extracted using rf waves. Effects employed to cool α particles can also in principle be used to heat the fusion ions; the possibility to design a configuration of rf waves which could be used to perform both tasks is demonstrated.
Date: March 17, 2008
Creator: A.I. Zhmoginov, N.J. Fisch
Partner: UNT Libraries Government Documents Department
open access

The Low-Income Home Energy Assistance Program: How are State Allotments Determined?

Description: This report discusses the Low-Income Home Energy Assistance Program (LIHEAP), which is a block grant program under which the federal government provides states annual grants to operate multi-component home energy assistance programs for needy households.
Date: April 17, 2001
Creator: Abbey, Craig W.
Partner: UNT Libraries Government Documents Department
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Ion Deflection for Final Optics In Laser Inertial Fusion Power Plants

Description: Left unprotected, both transmissive and reflective final optics in a laser inertial fusion power plant would quickly fail from melting, pulsed thermal stresses, or degradation of optical properties as a result of ion implantation. One potential option for mitigating this threat is to magnetically deflect the ions such that they are directed into a robust energy dump. In this paper we detail integrated studies that have been carried out to asses the viability of this approach for protecting final optics.
Date: November 17, 2006
Creator: Abbott, R P & Latkowski, J F
Partner: UNT Libraries Government Documents Department
open access

The On-Orbit Calibrations for the Fermi Large Area Telescope

Description: The Large Area Telescope (LAT) on-board the Fermi Gamma-ray Space Telescope began its on-orbit operations on June 23, 2008. Calibrations, defined in a generic sense, correspond to synchronization of trigger signals, optimization of delays for latching data, determination of detector thresholds, gains and responses, evaluation of the perimeter of the South Atlantic Anomaly (SAA), measurements of live time, of absolute time, and internal and spacecraft boresight alignments. Here we describe on-orbit calibration results obtained using known astrophysical sources, galactic cosmic rays, and charge injection into the front-end electronics of each detector. Instrument response functions will be described in a separate publication. This paper demonstrates the stability of calibrations and describes minor changes observed since launch. These results have been used to calibrate the LAT datasets to be publicly released in August 2009.
Date: November 17, 2011
Creator: Abdo, Aous A.; /Naval Research Lab, Wash., D.C.; Ackermann, M.; /Stanford U., HEPL /KIPAC, Menlo Park /Stanford U., Phys. Dept.; Ajello, M.; /Stanford U., HEPL /KIPAC, Menlo Park /Stanford U., Phys. Dept. et al.
Partner: UNT Libraries Government Documents Department
open access

Pulsed Gamma-Rays From the Millisecond Pulsar J0030+0451 with the Fermi Large Area Telescope

Description: We report the discovery of gamma-ray pulsations from the nearby isolated millisecond pulsar PSR J0030+0451 with the Large Area Telescope (LAT) on the Fermi Gamma-ray Space Telescope (formerly GLAST). This discovery makes PSR J0030+0451 the second millisecond pulsar to be detected in gamma-rays after PSR J0218+4232, observed by the EGRET instrument on the Compton Gamma Ray Observatory. The spin-down power {dot E} = 3.5 x 10{sup 33} ergs s{sup -1} is an order of magnitude lower than the empirical lower bound of previously known gamma-ray pulsars. The emission profile is characterized by two narrow peaks, respectively 0.07 {+-} 0.01 and 0.08 {+-} 0.02 wide, separated by 0.44 {+-} 0.02 in phase. The first gamma-ray peak falls 0.15 {+-} 0.01 after the main radio peak. The pulse shape is similar to that of the 'normal' gamma-ray pulsars. An exponentially cut-off power-law fit of the emission spectrum leads to an integral photon flux above 100 MeV of (6.76 {+-} 1.05 {+-} 1.35) x 10{sup -8} cm{sup -2} s{sup -1} with cut-off energy (1.7 {+-} 0.4 {+-} 0.5) GeV. Based on its parallax distance of (300 {+-} 90) pc, we obtain a gamma-ray efficiency L{sub {gamma}}/{dot E} {approx_equal} 15% for the conversion of spin-down energy rate into gamma-ray radiation, assuming isotropic emission.
Date: November 17, 2011
Creator: Abdo, Aous A.; /Naval Research Lab, Wash., D.C.; Ackermann, M.; /Stanford U., HEPL /KIPAC, Menlo Park /Stanford U., Phys. Dept.; Atwood, W.B.; /UC, Santa Cruz et al.
Partner: UNT Libraries Government Documents Department
open access

[Microsoft Educational CDROM Products, February 17, 1995]

Description: Photocopy of a letter from Julie Abel, Program Associate, Getty Center for Education in the Arts, to the Regional Institute Directors, in discussion of the Microsoft education CD ROM products inventory in relation to the arts education. Abel writes that she is sending them this inventory in order to get their thoughts on if or how they could be used in the summer institutes or the national specialty programs. If the CD's were used, the Getty would need a report back from the directors on how they were used and by who.
Date: February 17, 1995
Creator: Abel, Julie
Partner: UNT Libraries Special Collections
open access

[Letter from Julie Anne Abel to Regional Institute Directors, September 17, 1992]

Description: A letter from Julie Anne Abel to regional institute directors about requesting more information from the directors in order to update a chart for The Getty Center for Education in the Arts Advisory Committee. Attached documents include cumulative data for the North Texas Institute for Educators on the Visual Arts and a fax letter.
Date: September 17, 1992
Creator: Abel, Julie Anne
Partner: UNT Libraries Special Collections
open access

Effect of Inert Gas Additive Species on Cl(2) High Density Plasma Etching of Compound Semiconductors: Part II. InP, InSb, InGaP and InGaAs

Description: The effects of the additive noble gases He, Ar and Xe on chlorine-based Inductively Coupled Plasma etching of InP, InSb, InGaP and InGaAs were studied as a function of source power, chuck power and discharge composition. The etch rates of all materials with C12/He and C12/Xe are greater than with C12/Ar. Etch rates in excess of 4.8 pndmin for InP and InSb with C12/He or C12/Xe, 0.9 pndmin for InGaP with C12/Xe, and 3.8 prdmin for InGaAs with Clz/Xe were obtained at 750 W ICP power, 250 W rf power, - 1570 C12 and 5 mTorr. All three plasma chemistries produced smooth morphologies for the etched InGaP surfaces, while the etched surface of InP showed rough morphology under all conditions.
Date: December 17, 1998
Creator: Abernathy, C.R.; Cho, H.; Hahn, Y.B.; Hays, D.C.; Jung, K.B.; Pearton, S.J. et al.
Partner: UNT Libraries Government Documents Department
open access

The effect of stick-force gradient and stick gearing on the tracking accuracy of a fighter airplane

Description: Report presenting steady straight-and-level and steady turning tracking runs against an aerial target using an F-51H airplane equipped with a fixed optical sight and with various combinations of maneuvering stick-force and stick-deflection gradients. Results regarding aim wander, elevator movement, and stick-force variation for various test conditions are provided.
Date: December 17, 1954
Creator: Abramovitz, Marvin & Van Dyke, Rudolph D., Jr.
Partner: UNT Libraries Government Documents Department
open access

Investigation of internal film cooling of exhaust nozzle of a 1000-pound-thrust liquid-ammonia liquid-oxygen rocket

Description: Report presenting an investigation of internal film cooling of the exhaust nozzle of a 1000-pound-thrust liquid ammonia liquid-oxygen rocket engine. With water as a coolant, approximately 16 percent of the total propellant and coolant flow was required to film-cool the entire nozzle and with anhydrous liquid ammonia, approximately 19 percent of the total flow was required. Results regarding the coolant results and performance results are provided.
Date: June 17, 1952
Creator: Abramson, Andrew E.
Partner: UNT Libraries Government Documents Department
open access

Theory of high-T{sub c} cuprates based on experimental evidence.

Description: A model of superconductivity in layered high-temperature superconducting cuprates is proposed, based on the extended saddle point singularities in the electron spectrum, weak screening of the Coulomb interaction and phonon-mediated interaction between electrons plus a small short-range repulsion of Hund's, or spin-fluctuation, origin. This permits to explain the large values of T{sub c}, features of the isotope effect on oxygen and copper, the existence of two types of the order parameter, the peak in the inelastic neutron scattering, the positive curvature of the upper critical field, as function of temperature etc.
Date: August 17, 1999
Creator: Abrikosov, A. A.
Partner: UNT Libraries Government Documents Department
open access

EARLY ENTRANCE COPRODUCTION PLANT

Description: The overall objective of this project is the three-phase development of an Early Entrance Coproduction Plant (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 accomplishments of Phase I are discussed in detail in this Phase I Concept Report. A RD and T Plan and a preliminary project financing plan have been developed and are submitted separately from this report.
Date: May 17, 2001
Creator: Abughazaleh, John S.; Ahmed, Mushtaq; Anand, Ashok; Anderson, John H.; Benham, Charles; Brent, Fred D. et al.
Partner: UNT Libraries Government Documents Department
open access

PWR AXIAL BURNUP PROFILE ANALYSIS

Description: The purpose of this activity is to develop a representative ''limiting'' axial burnup profile for pressurized water reactors (PWRs), which would encompass the isotopic axial variations caused by different assembly irradiation histories, and produce conservative isotopics with respect to criticality. The effect that the low burnup regions near the ends of spent fuel have on system reactivity is termed the ''end-effect''. This calculation will quantify the end-effects associated with Pressurized Water Reactor (PWR) fuel assemblies emplaced in a hypothetical 21 PWR waste package. The scope of this calculation covers an initial enrichment range of 3.0 through 5.0 wt% U-235 and a burnup range of 10 through 50 GWd/MTU. This activity supports the validation of the process for ensuring conservative generation of spent fuel isotopics with respect to criticality safety applications, and the use of burnup credit for commercial spent nuclear fuel. The intended use of these results will be in the development of PWR waste package loading curves, and applications involving burnup credit. Limitations of this evaluation are that the limiting profiles are only confirmed for use with the B&W 15 x 15 fuel assembly design. However, this assembly design is considered bounding of all other typical commercial PWR fuel assembly designs. This calculation is subject to the Quality Assurance Requirements and Description (QARD) because this activity supports investigations of items or barriers on the Q-list (YMP 2001).
Date: September 17, 2003
Creator: Acaglione, J.M.
Partner: UNT Libraries Government Documents Department
open access

Operation of a Free-Electron Laser from the Extreme Ultraviolet to the Water Window

Description: We report results on the performance of a free-electron laser operating at a wavelength of 13.7 nm where unprecedented peak and average powers for a coherent extreme-ultraviolet radiation source have been measured. In the saturation regime, the peak energy approached 170 {micro}J for individual pulses, and the average energy per pulse reached 70 {micro}J. The pulse duration was in the region of 10 fs, and peak powers of 10 GW were achieved. At a pulse repetition frequency of 700 pulses per second, the average extreme-ultraviolet power reached 20mW. The output beam also contained a significant contribution from odd harmonics of approximately 0.6% and 0.03% for the 3rd (4.6 nm) and the 5th (2.75 nm) harmonics, respectively. At 2.75 nm the 5th harmonic of the radiation reaches deep into the water window, a wavelength range that is crucially important for the investigation of biological samples.
Date: December 17, 2007
Creator: Ackermann, W.; Asova, G.; Ayvazyan, V.; Azima, A.; Baboi, N.; Bahr, J. et al.
Partner: UNT Libraries Government Documents Department
open access

Commentary on “Experimental Measurements and Equilibrium Study of Functional D-Sorbitol in Good and Anti-Solvent Binary Mixtures”

Description: This article provides a commentary on the published equation coefficients for mathematically describing the solubility behavior of D-sorbitol in binary acetonitrile + ethanol solvent mixtures using the modified Apelblat, Combined Nearly Ideal Binary Solvent/Redlich-Kister (CNIBS/R-K) and Jouyban-Acree models.
Date: May 11, 2017
Creator: Acree, William E. (William Eugene)
Partner: UNT College of Science

Commentary on "Solubility and solution thermodynamics of cetilistat in water and (acetone, isopropyl alcohol, acetonitrile) binary solvent mixtures"

Description: This article reanalyzes experimental solubility data reported in the recent paper "Solubility and solution thermodynamics of cetilistat in water and (acetone, isopropyl alcohol, acetonitrile) binary solvent mixtures" in the Journal of Molecular Liquids.
Date: January 17, 2017
Creator: Acree, William E. (William Eugene)
Partner: UNT College of Arts and Sciences
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