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Chemical Technology Division Unit Operations Section Monthly Progress Report, September 1961

Description: Nine samples of ThO/sub 2/ -UO/sub 2/ prepared as part of the solgel process development studies showed no consistent effects from small variations in several process parameters. The reaction of methane and copper oxide was studied. Engineering studies of the continuous dissolution of simulated U-Zr-Sn fuels in 6.5 M NH4F, 0.6-1.0 M NH/sub 4/NO/sub 3/, 0.1 M H/sub 2/O/sub 2/ were continued in modified 6-in.-dia. equipment. A total of 1642 kg of U from NaK bonded SRE Core I fuel rods wad dejacke… more
Date: April 1, 1962
Creator: Whatley, M. E.; Haas, P. A.; Horton, R. W.; Ryon, A. D.; Suddath, J. C. & Watson, C. D.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Murgatroyd-an Ibm 7090 Program for the Analysis of the Kinetics of the Msre

Description: The IBM 7090 program Murgatroyd is a revised and extended version of the IBM 704 program PET-I, which solves (by a fifth-order Runge-Kutta procedure) the coupled firstorder differential equations for power, delayed neutron concentration, and temperature in a one-region reactor as a function of time, given an input reactivity variation represented by a series of linear ramps. The basic extensions were those which were necessary to include the effects of the separate heat capacities and temperatu… more
Date: April 1, 1962
Creator: Nestor, C. W. Jr.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Continuum damping of low-n toroidicity-induced shear Alfven eigenmodes

Description: The effect of resonant continuum damping is investigated for the low-mode-number, toroidicity-induced, global shear Alfven eigenmodes, which can be self-excited by energetic circulating alpha particles in an ignited tokamak plasma. Resonant interaction with the shear Alfven continuum is possible for these eigenmodes, especially near the plasma periphery, leading to significant dissipation, which is typically larger than direct bulk plasma dissipation rates. Two perturbation methods are develope… more
Date: September 1, 1991
Creator: Berk, H.L.; Van Dam, J.W.; Guo, Z. & Lindberg, D.M.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Power excitation by the use of a rf wiggler

Description: It is well-known that there are difficulties to obtain rf power sources of significant amount for frequencies larger than 3 GHz. Yet, rf sources in the centimeter/millimeter wavelength range would be very useful to drive, for example, high-gradient accelerating linacs for electron-positron linear colliders. We would like to propose an alternative method to produce such radiation. It makes use of a short electron bunch traveling along the axis of a waveguide which is at the same time excited by … more
Date: January 1, 1992
Creator: Ruggiero, Alessandro G.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Boundary element formulation for planar time-dependent inelastic deformation of plates with cutouts

Description: A boundary element formulation for planar, time-dependent, inelastic deformation problems for bodies with cutouts is presented in this paper. A stress function description for these nonlinear problems leads to a nonhomogeneous biharmonic equation for the stress function rate. An integral representation of the solution uses modified kernels which guarantee that the cutout boundary is traction free for all time. This incorporation of the effect of the cutout on the stress field into the kernels l… more
Date: February 1, 1980
Creator: Mukherjee, S. & Morjaria, M.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Final Report of Modeling of CWM Droplet Combustion

Description: The objective of the present study was to develop a one-dimensional, unsteady state model for coal-water mixture droplet combustion, and to compare the characteristic times for the various processes, such as water vaporization, devolatilization and char oxidation with available experimental data. A water film surrounding a spherical coal particle is considered to undergo vaporization by heat transfer from the hot air. After the water vaporization is complete, devolatilization begins. This proce… more
Date: October 1, 1983
Creator: Pandalai, Krish; Aggarwal, Suresh & Sirignano, William
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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The interpretation of reflectometry measurements of plasma fluctuations

Description: Wave reflections from density fluctuations with magnitudes and frequencies typical of drift waves have been investigated. Both drift waves and the reflected phase and amplitude depend on the density gradient scale length, and this common feature implies that both the angular deviation of a normally propagating wave and the phase change on reflection are of order unity. Thus the surface will always appear rough'' and amplitude variations will always be large. For smaller amplitude waves numerica… more
Date: October 1, 1991
Creator: Bretz, N.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Electron-beam envelopes and matching for a combined wiggler and alternating-gradient quadrupole channel

Description: This work studies the electron-beam envelopes and matching for a combined wiggler and alternating-gradient quadrupole field for a free-electron laser (FEL) that will be operated in the VUV or XUV wavelength region. The quadrupole field is assumed to vary continuously along the symmetry axis. The linearized equations of electron motion are solved analytically by using the two-scale perturbation method for a plane polarized wiggler. The electron-beam envelopes and the envelope equations, as well … more
Date: January 1, 1985
Creator: Wang, T. F. & Cooper, R. K.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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New Solutions of the Boltzmann Equation for Monoenergetic Neutron Transport in Spherical Geometry

Description: Solutions of the Boltzmann equation for monoenergetic neutron transport in spherical geometry are derived which are respectively singular and regular at the center of the sphere. A few specific partial singular solutions are presented. The regular solutions in spherical geometry are constructed by superposition of solutions in plane geometry which belong to the same k. Finally, the solutions are compared with their representations by a series of spherical harmonics. (D. L.C.)
Date: November 17, 1961
Creator: Kofink, W.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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D/sup -/ production by multiple charge-transfer collisions of low-energy D ions and atoms in cesium vapor

Description: The production of D/sup -/ by multiple charge-transfer collisions of a D/sup +/ beam in a cesium-vapor target is considered for D/sup +/ energies above 300 eV. The cross sections relevant to D/sup -/ formation are obtained by a least-squares fit of three-charge-state differential equations to experimental yield curves. Implications for production of intense negative-ion beams are discussed, and speculations are made about extrapolation to lower engeries.
Date: January 22, 1978
Creator: Hooper, E. B. Jr.; Willmann, P. A. & Schlachter, A. S.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Estimate of the longitudinal self electric field of an ion beam

Description: The self electric field on the axis of an ion beam of radius a in a conducting cylinder of radius b is given. The formula assumes that the radius of the conducting cylinder is much smaller than the length of the ion beam (b much less than L) and that E/sub z/ is calculated away from the edge of the beam (vertical bar z vertical bar less than vertical bar L/2 vertical bar). For the HIDE parameters, i.e., loosely speaking a 50 TW, 100 JK, multi-GeV heavy ion beam, the assumption b much less than … more
Date: January 1, 1977
Creator: Irani, A.A.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Theory of chemical kinetics. Progress report, May 1, 1977--January 15, 1978. [Massachusetts Inst. of Tech. , Cambridge]

Description: Recent work on Franck--Condon factors in studies of the dynamics of chemical reactions is related; emphasis was on simple chemical rearrangement reactions. Other work concerned collision-free unimolecular decomposition of large molecules at a given total energy, equations of motion for simple quantum systems that are strongly driven by an external field and are modulated stochastically by a coupling to a bath, and the efficiency of rate processes in irreversible chemical reactions. This report … more
Date: unknown
Creator: Ross, J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Magnetic fusion with high energy self-colliding ion beams

Description: Field-reversed configurations of energetic large orbit ions with neutralizing electrons have been proposed as the basis of a fusion reactor. Vlasov equilibria consisting of a ring or an annulus have been investigated. A stability analysis has been carried out for a long thin layer of energetic ions in a low density background plasma. There is a growing body of experimental evidence from tokamaks that energetic ions slow down and diffuse in accordance with classical theory in the presence of lar… more
Date: June 1, 1992
Creator: Rostoker, N.; Wessel, F. (California Univ., Irvine, CA (United States)); Maglich, B. (Advanced Physics Corp., Irvine, CA (United States)) & Fisher, A. (Naval Research Lab., Washington, DC (United States))
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Stochastic modelling of physiologic processes with radiotracers and positron emission tomography

Description: The compartment model, so often used in nuclear medicine and in pharmacokinetics, is formed by a set of linear differential equations of order one with constant coefficients; its validity depends upon the hypothesis that the system described contains a finite number of components, and that each component is homogeneous. These hypotheses exclude the presence of diffusion and of age-dependent processes, or in general of transport of a non-Markovian nature. The fact that frequently the experimenta… more
Date: January 1, 1982
Creator: Rescigno, A.; Lambrecht, R. M. & Duncan, C. C.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Coarse-node computations with an adaptive node structure

Description: The analysis with COMMIX of liquid metal reactor (LMR) intermediate heat exchanger (IHX) transients that are characterized by low flows, and especially imbalanced low flows, shows that if a coarse-node structure is used the predicted temperatures are significantly different than those given by a fine-node structure. If a fine-node structure is used, for problems that involve a large part of the plant, the computation time becomes excessive. This paper presents an improved version of an adaptive… more
Date: January 1, 1988
Creator: Tzanos, C.P.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Is the two-term expansion valid for highly anisotropic systems. The Townsend ionization coefficient in strong runaway as a test case

Description: The Townsend ionization coefficient in the strong runaway regime is calculated within the framework of the two-term expansion. Results are compared to the 1-D model. General features of the two models are qualitatively similar, but quantitative differences by factors of approx. 2 are observed.
Date: July 15, 1982
Creator: Yu, S. S. & Melendez, R. E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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PHYSICS ANALYSIS OF THE JUGGERNAUT REACTOR

Description: The JUGGERNAUT is an intermediate-power research reactor designed and constructed as a supporting facility for chemistry and physics research. The design of this reactor is similar to that of the ARGONAUT, and those methods of evaluating the nuclear characteristics of the ARGONAUT which gave good agreement with experimental data were considered applicable to the analysis of the JUGGERNAUT. The analyses for both the JUGGERNAUT and the ARGONAUT were based on a modified two-group theory. The criti… more
Date: July 1, 1962
Creator: Moon, D.P.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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A PROGRAM OF RESEARCH AND CALCULATIONS OF RESONANCE ABSORPTION. Final Report

Description: A direct numerical integration of the integral equation for the average collision density in the absorber was previously suggested in a discussion of resonance absorption. The implementation of this program is considered. The method of calculation, comparison with experimental data, and the computer code developed are described. The method of integration, computation of cross sections, selection of mesh size, integration interval, outside correction, the Dancoff correction, and unresolved reson… more
Date: August 28, 1961
Creator: Nordheim, L.W.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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CALCULATIONS OF THE DOPPLER COEFFICIENT OF LARGE CERAMIC-FUELED FAST REACTORS

Description: ABS>Calculations of the Doppler coefficient of large, ceramicfueled fast reactors containing plutonium were made by means of the ELMOE program to provide accurate flux calculations. The temperature-dependent cross sections of P. Greebler et al., for U/sup 238/ and Pu/sup 239/ were used. Doppler coefficients of the order of 10/sup -5/ ntermediate tem k/ C were obtained, in agreement with Greebler's results. Coefficients of carbide fueled reactors are about 0.7 of those of oxide-fueled reactors a… more
Date: August 1, 1962
Creator: Bhide, M.G. & Hummel, H.H.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Multi-grid and ICCG for problems with interfaces

Description: Computation times for the multi-grid (MG) algorithm, the incomplete Cholesky conjugate gradient (ICCG) algorithm (J. Comp. Phys. 26, 43-65 (1978); Math. Comp. 31, 148-162 (1977)), and the modified ICCG (MICCG) algorithm (BIT 18, 142-156 (1978)) to solve elliptic partial differential equations are compared. The MICCG and ICCG algorithms are more robust than the MG for general positive definite systems. A major advantage of the MG algorithm is that the structure of the problem can be exploited to… more
Date: January 1, 1980
Creator: Dendy, J.E. & Hyman, J.M.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Fermi molecular dynamics

Description: classical many body models supplemented by repulsive momentum-dependent potentials to simulate the Pauli and Heisenberg principles have been use with some success for nuclear and atomic bound state and collision problems. They are capable of describing mean ground state properties, hydrodynamics, shocks (if warranted by the physics), viscosity, correlations, clustering, fragmentation, etc. We have become interested in the Feldmeier Gaussian packet formulation since it is based on a variational … more
Date: January 1, 1991
Creator: Wilets, L. & Beck, W.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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