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Macroscopic constraints on string unification

Description: The comparison of sting theory with experiment requires a huge extrapolation from the microscopic distances, of order of the Planck length, up to the macroscopic laboratory distances. The quantum effects give rise to large corrections to the macroscopic predictions of sting unification. I discus the model-independent constraints on the gravitational sector of string theory due to the inevitable existence of universal Fradkin-Tseytlin dilatons. 9 refs.
Date: March 1, 1989
Creator: Taylor, T.R.
Partner: UNT Libraries Government Documents Department
open access

Catalysis studies

Description: The New Research Initiatives Program (NRIP) project on catalysis in Los Alamos Scientific Laboratory (LASL) Group CMB-8 has made significant progress towards performing the first basic in situ experimental studies of heterogeneous catalysis on solid compound surfaces in a LEED-Auger system. To further understand the surface crystallography of a possible catalyst compound, LEED-Auger measurements were made on UO/sub 2/(approximately 100) vicinal surfaces. These (approximately 100) vicinal surfac… more
Date: November 1, 1977
Creator: Taylor, T. N. & Ellis, W. P.
Partner: UNT Libraries Government Documents Department
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Ion scattering studies of some actinide materials. [E < 650 eV]

Description: Surfaces of polycrystalline U, Th, and single crystalline UO/sub 2/(111) were examined with He/sup +/, Ne/sup +/, and Ar/sup +/ at incident beam energies E/sub i/ less than or equal to 650 eV. A double-pass cylindrical mirror analyzer was used in a custom vacuum system intended primarily for UPS. The approach was to determine if the instrument could serve in a complementary ISS capacity and, if so, what the ion scattering conditions are for detecting surface oxygen and the actinides. Data are p… more
Date: January 1, 1977
Creator: Ellis, W. P. & Taylor, T. N.
Partner: UNT Libraries Government Documents Department
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Reactive Barrier Treatment Wall Technology for Remediation of Inorganic Contaminated Groundwater

Description: The potential for subsurface reactive barrier wall technology to aid in remediation of contaminated groundwater in situ has prompted testing of novel porous media. Treatability testing of contaminants contacted with various media has been conducted using equilibrium batch techniques, one-dimensional (1-D) columns and 2-D boxes. Continuous mode column and box experiments are useful for assessing critical design parameters under dynamic flow conditions. Experiments have been conducted using a mul… more
Date: March 1, 2001
Creator: Taylor, T. & Al, Et
Partner: UNT Libraries Government Documents Department
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Plasma synthesis and characterization of ultrafine SiC

Description: Ultrafine SiC powders have been prepared by gas phase synthesis from silane and methane in an argon thermal rf-plasma. Bulk properties of the powders were determined by elemental analysis, x-ray diffractin, helium pycnometry, and BET surface area measurements. The near-surface composition and structure of the particles were examined by x-ray photoelectron spectroscopy (XPS) and transmission electron microscopy (TEM). In addition to free silicon and carbon particles in the powders, free carbon a… more
Date: January 1, 1986
Creator: Vogt, G. J.; Phillips, D. S. & Taylor, T. N.
Partner: UNT Libraries Government Documents Department
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Influence of adsorbed Bi on the chemisorption properties of Pt(111): H/sub 2/, CO, and O/sub 2/

Description: The growth modes and interactions of vapor-deposited Bi on a clean Pt(111) surface and its effects on the chemisorption of H/sub 2/, CO, and O/sub 2/ have been monitored by Auger electron spectroscopy (AES), low-energy electron diffraction (LEED), and thermal desorption mass spectroscopy (TDMS). For submonolayer Bi coverages, LEED patterns were observed to progress with increasing coverage through p(2 x 2), (..sqrt..3 x ..sqrt..3)R30/sup 0/, p(3 x 3), and p(4 x 4) structures. The Bi TDMS and AE… more
Date: January 1, 1984
Creator: Paffett, M. T.; Campbell, C. T. & Taylor, T. N.
Partner: UNT Libraries Government Documents Department
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Oxide thermal stability on gamma titanium aluminide

Description: Surface composition plays an important role in hydrogen embrittlement of the TiAl-based structural alloys proposed for NASP. A clear understanding of the thermal stability of the oxide on the various titanium aluminides will give important insight into the way that hydrogen reacts with these materials in the initial step of the hydriding process. The present work addresses these issues by using surface probes to analyze the thermal stability of an oxide formed under atmospheric conditions on ga… more
Date: January 1, 1990
Creator: Taylor, T. N.
Partner: UNT Libraries Government Documents Department
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Studies of the Ag/Cu(110) bimetallic interface using optical second-harmonic generation

Description: Optical second harmonic generation (SHG) has recently been shown to be a sensitive, real-time, in situ probe for studying interfaces under many different environments. With regard to atomically clean well-characterized surfaces, SHG has been shown to be sensitive to submonolayer coverages of adsorbates, the structural symmetry or molecular arrangement on the surface, and the surface reordering observed during laser induced melting and recrystallization. Previous SHG studies of bimetallic system… more
Date: January 1, 1989
Creator: Muenchausen, R. E.; Hoffbauer, M. A. & Taylor, T. N.
Partner: UNT Libraries Government Documents Department
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Oxide properties of a gamma titanium aluminide: A surface science study

Description: The surface properties of oxides grown on a gamma titanium aluminide (2 at. % Nb) have been examined using a x-ray photoelectron spectroscopy (XPS) and secondary-ion mass spectroscopy (SIMS). An oxide formed on the sample during air exposure at room temperature was thermally destabilized in ultra-high vacuum. The heating largely decomposed the advanced Ti oxidation states to give a predominate +2 valence configuration at 600{degrees}C, while the Al oxide was somewhat enhanced for the same treat… more
Date: January 1, 1991
Creator: Taylor, T. N. & Paffett, M. T.
Partner: UNT Libraries Government Documents Department
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Radiation and electrical safety systems for PEP

Description: At SLAC, the Personnel Protection System (PPS) protects people from radiation hazards. For PEP, the system has been expanded to include protection against electrical and RF hazards. This paper describes the overall system design, giving particular attention to the novel features not found in similar systems in other areas of SLAC. These include the Restricted Access Mode to allow limited occupancy in the ring while high voltage or RF may be present, the automatic badge reader system for improvi… more
Date: February 1, 1981
Creator: Smith, H.; Constant, T.; Crook, K.; Fitch, J. & Taylor, T.
Partner: UNT Libraries Government Documents Department
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The reaction of vapor-deposited Al with Cu oxides

Description: Interfaces formed by controlled deposition of Al on Cu oxides at 300K have been characterized using Auger electron spectroscopy (AES) and x-ray photoelectron spectroscopy (XPS). When Al is deposited onto a thin oxide grown on Cu(110) by atmospheric exposure, it completely scavenges the oxygen from the substrate material, increasing the O(1s) binding energy by 2.0 eV to give the value found for atmospheric oxidation of a thin Al film. Similar oxygen behavior is seen for Al deposition on sputter-… more
Date: January 1, 1990
Creator: Taylor, T. N. & Martin, J. A.
Partner: UNT Libraries Government Documents Department
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Evaluation of ASME Section XI Reference Level Sensitivity for Initiation of Ultrasonic Inspection Examination

Description: This report evaluates the change in inspection sensitivity resulting in major changes of ASME Boiler and Pressure Vessel Code Section XI between 1974 and 1977 Editions. It was found that the inspection sensitivity resulting from requirements of the 1977 Edition of Section XI were not adequate to detect minimum flaws referenced by same Code.
Date: April 1, 1981
Creator: Taylor, T. T. & Selby, G. P.
Partner: UNT Libraries Government Documents Department
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Physics of advanced tokamaks

Description: Significant reductions in the size and cost of a fusion power plant core can be realized if simultaneous improvements in the energy replacement time, {tau}{sub E}, and the plasma pressure or beta, {beta}{sub T} = 2 {micro}{sub 0} <P>/B{sup 2} can be achieved in steady-state conditions with high self-driven, bootstrap current fraction. Significant recent progress has been made in experimentally achieving these high performance regimes and in developing a theoretical understanding of the underlyi… more
Date: November 1997
Creator: Taylor, T. S.
Partner: UNT Libraries Government Documents Department
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Advanced tokamak physics experiments on DIII-D

Description: Significant reductions in the size and cost of a fusion power plant core can be realized if simultaneous improvements in the energy confinement time ({tau}{sub E}) and the plasma pressure (or beta {beta}{sub T} = 2 {mu}{sub 0} < p > /B{sub T}{sup 2}) can be achieved in steady-state conditions with high self driven bootstrap current fraction. In addition, effective power exhaust and impurity and particle control is required. Significant progress has been made in experimentally achieving regimes … more
Date: December 1998
Creator: Taylor, T. S.
Partner: UNT Libraries Government Documents Department
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An assessment of nondestructive testing technologies for chemical weapons monitoring

Description: The US Department of Energy (DOE), with the US Army Chemical Research, Development and Engineering Center (CRDEC) under the sponsorship of the Defense Nuclear Agency (DNA), completed testing of Nondestructive Evaluation (NDE) technology on live agent systems. The tests were conducted at Tooele Army Depot during August 1992. The Nondestructive Evaluation systems were tested for potential use in verifying chemical treaty requirements. Five technologies, two neutron and three acoustic, were develo… more
Date: May 1, 1993
Creator: Taylor, T. T.
Partner: UNT Libraries Government Documents Department
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An assessment of nondestructive testing technologies for chemical weapons monitoring

Description: The US Department of Energy (DOE), with the US Army Chemical Research, Development and Engineering Center (CRDEC) under the sponsorship of the Defense Nuclear Agency (DNA), completed testing of Nondestructive Evaluation (NDE) technology on live agent systems. The tests were conducted at Tooele Army Depot during August 1992. The Nondestructive Evaluation systems were tested for potential use in verifying chemical treaty requirements. Five technologies, two neutron and three acoustic, were develo… more
Date: May 1, 1993
Creator: Taylor, T. T.
Partner: UNT Libraries Government Documents Department
open access

Growth and stability of Ag layers on Cu(110)

Description: Combined surface science and high energy ion beam techniques have been used to characterize the composition, structure and thermal stability of Ag layers < 900A thick on Cu(110). A uniform Ag/Cu surface composite is formed for one monolayer coverage. Analysis of its growth with LEED shows that the Ag is initially confined to the (110) troughs and that further deposition results in a Ag(111) layer exhibiting c(2 x 4) symmetry. This surface science determination of Ag coverage is consistent with … more
Date: January 1, 1986
Creator: Taylor, T. N.; Hoffbauer, M. A.; Maggiore, C. J. & Beery, J. G.
Partner: UNT Libraries Government Documents Department
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Detection of small-sized near-surface under-clad cracks for reactor pressure vessels

Description: The analysis of pressurized thermal shock (PTS) shows it is necessary for nondestructive evaluation to demonstrate high probability of detecting evaluation to demonstrate high probability of detecting cracks 0.250 inches deep and deeper at the clad/base metal interface. Ultrasonic techniques developed and used in Europe are evaluated in this paper for their applicability to US reactor pressure vessels for detecting cracks of interest for PTS. Flaw detectability experiments were carried out by t… more
Date: February 1, 1983
Creator: Taylor, T. T.; Crawford, S. L.; Doctor, S. R. & Posakony, G. J.
Partner: UNT Libraries Government Documents Department
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