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A Proposal to Study Small Angle Proton-Deuteron Scattering

Description: We propose an extension of the present p-p small angle scattering experiment to a measurement of p-d scattering using a deuterium gas jet. In 400 hours of beam time we will measure as a function of energy; (a) the slope of the small angle p-d scattering; (b) the real part of the forward p-d scattering; (c) the total p-d cross section; and (d) the coherent diffraction dissociation of protons on deuterons. No new apparatus is required or need be installed for the performance of this experiment.
Date: September 22, 1972
Creator: Bartenev, V.; Kuznetsov, A.; Morozov, B.; Nikitin, N.; Pilipenko, Y.; Popov, V. et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Characteristics of American coals in relation to their conversion into clean energy fuels. Quarterly technical progress report, July--September 1975

Description: Twenty-one coal samples have been collected and characterized. Sixty coals have been provided to other agencies at their request. The capability of controlling coal characteristics during preparation is being developed: large variations in volatile content occur within a given raw coal but, by controlling the preparation, a uniform product with the devised specifications can be produced. Studies have begun on the suitability of various coals and cokes for use in pressurized fixed bed gasifiers.… more
Date: December 1, 1975
Creator: Spackman, W.; Davis, A.; Walker, P. L.; Lovell, H. L.; Essenhigh, R. H.; Vastola, F. J. et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Set of thermal neutron-scattering experiments for the Weapons Neutron Research Facility

Description: Six classes of experiments form the base of a program of thermal neutron scattering at the Weapons Neutron Research (WNR) Facility. Three classes are to determine the average microscopic positions of atoms in materials and three are to determine the microscopic vibrations of these atoms. The first three classes concern (a) powder sample neutron diffraction, (b) small angle scattering, and (c) single crystal Laue diffraction. The second three concern (d) small kappa inelastic scattering, (e) sca… more
Date: December 1, 1975
Creator: Brugger, R. M.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Positron lifetimes in voids and other defects in annealed, neutron-irradiated aluminum

Description: Positron lifetimes were measured in neutron-irradiated high-purity aluminum single crystals, and companion small-angle x-ray scattering experiments were performed to determine the radius of gyration and volume fraction of radiation-induced voids. The lifetime data are consistent with a model in which positrons are trapped both in voids and in other defects which are tentatively identified as vacancy clusters bound to transmutation-produced silicon. The lifetime in the latter defects increased f… more
Date: January 1, 1976
Creator: McGervey, J. D.; Lindberg, V. W. & Hendricks, R. W.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Characteristics of American coals in relation to their conversion into clean energy fuels. Quarterly technical progress report, October--December 1975

Description: The actual coal gasification reaction is controlled diffusionally in the lower part of the bed and kinetically in the upper part of the bed. When closely size-graded pulverized coal particles undergo rapid devolatilization in a laminar flow reactor, the effect of heating-up time on weight loss is negligibly small. All other experimental conditions being equal, the smaller the particle, the greater is the weight loss. Reactivity of a char increases with increase in partial pressure of oxygen in … more
Date: February 1, 1976
Creator: Spackman, W.; Davis, A.; Walker, P. L.; Lovell, H. L.; Essenhigh, R. H.; Vastola, F. J. et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Coal technology program quarterly progress report for the period ending December 31, 1975

Description: Installation of the bench-scale hydrocarbonization research system was completed and initial pressurization was followed by heat up, leak checking, and testing of instrumentation. Shakedown runs were completed using 5 and 20 lb of pulverized coal as feed and pyrolyzing the coal at approx. 1050/sup 0/F under 5 atm of nitrogen pressure. Some excellent results have been obtained in the additive agglomeration studies using liquid additives designed for the petroleum industry. Characterization studi… more
Date: March 1, 1976
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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SWIMS: a small-angle multiple scattering computer code

Description: SWIMS (Sigmund and WInterbon Multiple Scattering) is a computer code for calculation of the angular dispersion of ion beams that undergo small-angle, incoherent multiple scattering by gaseous or solid media. The code uses the tabulated angular distributions of Sigmund and Winterbon for a Thomas-Fermi screened Coulomb potential. The fraction of the incident beam scattered into a cone defined by the polar angle ..cap alpha.. is computed as a function of ..cap alpha.. for reduced thicknesses over … more
Date: July 1, 1976
Creator: Sayer, R. O.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Design study of a time of flight small-angle diffractometer for a pulsed neutron source

Description: The design study for a neutron SAS instrument at Argonne's proposed Intense Pulsed Neutron Source (peak thermal neutron flux 10/sup 16/ n/cm/sup 2/-sec) indicates that an effective high-resolution TOF SAS diffractometer can be constructed. The design features include a converging slit collimator, provision for 5 x 5 cm/sup 2/ sample cross sectional area, and a 1 x 1 m/sup 2/, two-dimensional detector. The fractional wavelength resolution of the instrument is negligibly small for all wavelengths… more
Date: January 1, 1977
Creator: Carpenter, J.M. & Faber, J. Jr.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Determination of low-field critical parameters of superconducting niobium by small-angle neutron diffraction

Description: The perfect double-crystal small-angle diffraction technique enables measurement of scattering angles to within 0.3 arc sec. accuracy. At a wavelength of 2.55 A, this provides a resolution of 3 x 10/sup -6/ A/sup -1/ in the scattering vector. This technique has been used to study the anisotropic behavior of the critical parameters B/sub 0/ and H/sub c1/, characteristic of the first-order magnetic phase transition which occurs in low-kappa type-II superconductors. Magnetic fields were applied pa… more
Date: January 1, 1977
Creator: Christen, D. K.; Spooner, S.; Thorel, P. & Kerchner, H. R.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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New small angle neutron scattering (SANS) instrument at ORNL using a position sensitive area detector

Description: This paper describes the construction and operation of the small-angle neutron scattering instrument which has been set up at the Oak Ridge Research Reactor at ORNL. Motivation for work on this system to date has been the demonstration of the feasibility of the Borkowski-Kopp position-sensitive area detector and the use of pyrolytic graphite monochromating crystal pairs for small angle neutron scattering research. For a relatively modest cost, a serviceable experimental capability has been achi… more
Date: January 1, 1977
Creator: Child, H. R. & Spooner, S.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Recent improvements to RC-line encoded position-sensitive proportional counters

Description: Continuing research on the principles of position encoding with RC lines has advanced the design of position-sensitive proportional counters (PSPCs) to meet the requirements for high count rates (>10/sup 5/ counts/sec) and good spatial resolution (>10/sup 4/ spatial elements) in small-angle scattering experiments with x rays and neutrons. Low-noise preamplifiers were developed with pole-zero cancellation in the feedback circuit and modular linear amplifiers with passive RCL shaping which, compa… more
Date: January 1, 1977
Creator: Borkowski, C. J. & Kopp, M. K.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Characteristics of American coals in relation to their conversion into clean energy fuels. Quarterly technical progress report, January--March 1977

Description: Twenty-one coal samples have been added to the Penn State/ERDA Coal Sample Bank. Ninety-six sets of analytical data and 114 coal samples were provided upon request to other agencies engaged in coal research. Mass spectrometer and reactor systems have been used successfully in measuring the amount of vaporization (and pyrolysis) products of hydrocarbons in low concentrations in a helium carrier gas. Research has shown, using small angle x-ray scattering, that the pore structure of a char is a fu… more
Date: June 1, 1977
Creator: Spackman, W.; Davis, A.; Walker, P. L.; Lovell, H. L.; Essenhigh, R. H.; Vastola, F. J. et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Small-angle neutron scattering from voids in neutron irradiated type 304 stainless steel. [E > 0. 1 MeV]

Description: Preliminary small-angle neutron scattering results designed to investigate the structure of voids in neutron-irradiated polycrystalline annealed type 304 stainless steel were obtained. Specimens were subjected to irradiation at 400/sup 0/C to a fluence of 1.6 x 10/sup 23/ n/cm/sup 2/ (E > 0.1 MeV). Void interference effects were seen for voids having an average diameter of about 290 A. The distribution was ''gas-like''with an exclusion distance of 307 A. 1 figure, 1 table. (RWR)
Date: September 1, 1977
Creator: Child, H.R. & Spooner, S.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Remarks delivered at the awards ceremony

Description: For almost four decades, the distinguished trio of professors, W. W. Beeman, A. Guinier, and O. Kratky, have provided leadership of the field of small-angle scattering through both their teaching and their personal research. Collectively, they have authored or coauthored over 400 scientific articles and reviews, several books, and have been associated with over 140 graduate and postdoctoral students. It was thus appropriate that each should be honored for his outstanding contributions to the fi… more
Date: June 1, 1978
Creator: Brumberger, H. & Hendricks, R.W. (eds.)
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Static correlations in semidilute polymer solutions

Description: This document reports small-angle x-ray scattering measurements of the concentration dependence of the correlation ranges in semi-dilute solutions of polystyrene in butanone. Results confirm the assumption that xi scales with concentration C (xi approx. C/sup -//sup x/) and xi are independent of the molecular weight. (DLC)
Date: January 1, 1979
Creator: Schaefer, D. W. & Hendricks, R. W.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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/sup 235/Cf anti. nu. discrepancy and the sulfur discrepancy

Description: The cantankerous discrepancy among measured values of anti ..nu.. for /sup 235/Cf appears at last to be nearing a final resolution. A recent review has summarized the progress that has been achieved through revaluation upward by 0.5% of two manganese bath values anti ..nu.. and the performance of a new liquid scintillator measurement. A new manganese bath measurement at INEL is in reasonably good agreement with previous manganese bath values of /sup 235/Cf anti ..nu... It now appears that the m… more
Date: January 1, 1979
Creator: Smith, J. R.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Voids in neutron-irradiated metals and alloys

Description: Small-angle x-ray and neutron scattering are powerful analytical tools for investigating long-range fluctuations in electron (x-rays) or magnetic moment (neutrons) densities in materials. In recent years they have yielded valuable information about voids, void size distributions, and swelling in aluminum, aluminum alloys, copper, molybdenum, nickel, nickel-aluminum, niobium and niobium alloys, stainless steels, graphite and silicon carbide. In the case of aluminum, information concerning the sh… more
Date: January 1, 1980
Creator: Hendricks, R.W.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Small-angle x-ray scattering studies of the porosity of coals and chars. Quarterly progress report, July 1-September 30, 1980

Description: Considerable effort has been devoted to checking and verifying some of the preliminary data reported previously. The technique employed in the past for measuring the x-ray transmission of the samples has been modified to provide more accurate values of the transmission. These transmission measurements are important for quantitative interpretation of the scattering data both because they are needed to determine the amount of background scattering that must be subtracted from a measured scatterin… more
Date: September 1, 1980
Creator: Schmidt, P.W.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Small-angle physics at ISABELLE

Description: ISABELLE will be commissioned a few years after the anti p p colliders, whose plans and first results have been presented here. A look at the design goals for ISABELLE reveals that the two salient features offered in compensation for the later turn-on are high luminosity and (2 x 10/sup 5/-10/sup 6/mb/sup -1/sec/sup -1/) and the number of intersections available for physics. With expected Z/sup 0/ detection rates of in UA1, it is clear that all but the most rudimentary features of the standard … more
Date: January 1, 1981
Creator: Aronson, S.H.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Quantitative comparison of the void distribution in a. beta. '-phase Ni-Al-In alloy using x-ray small-angle scattering and transmission-electron microscopy. [Ni-51. 2 at. % Al-2. 6 at. % In]

Description: Small-angle scattering is a rather mature discipline which can yield valuable information on the size, amount, and distribution of inhomogeneities encountered in materials-science research. Methods have been publisheed which permit one to extend the standard analysis of data from a small-angle-scattering experiment to include determination of the distribution of particle sizes. This extended analysis has been carried out for voids in a ..beta..'-phase Ni-Al-In alloy, and, in order to assess the… more
Date: November 1, 1981
Creator: Epperson, J. E.; Loomis, B. A. & Lin, J. S.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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