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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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Shear alfven resonances in Tokapole II

Description: It has been suggested that efficient heating can occur by coupling energy through the shear Alfven resonance that is predicted to occur at particular locations within inhomogeneous plasmas. This heating mechanism should be applicable to tokamaks; however, the existence of the resonances in tokamaks has not yet been established experimentally. We present here direct observations of localized enhancement in the driven wave magnetic field which are compatible with theoretical predictions for the s… more
Date: March 1, 1982
Creator: Witherspoon, F.D.; Prager, S.C. & Sprott, J.C.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Solder fatigue reduction in point focus photovoltaic concentrator modules

Description: Solder fatigue tests have been conducted on point focus photovoltaic concentration cell assemblies to identify a baseline fatigue life and to quantify the fatigue life improvements that result using a copper-molybdenum-copper low-expansion insert between the solar cell and copper heat spreader. Solder microstructural changes and fatigue crack growth were identified using cross sections and ultrasonic scans of the fatigue solder joints. The Coffin-Manson and Total Strain fatigue models for low-c… more
Date: January 1, 1991
Creator: Hund, T. D. & Burchett, S. N.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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REMOTELY CONTROLLED SHEARING OF PIPE AND STRUCTURAL MEMBERS

Description: A shearing tool was developed for remotely controlled severing of pipes or structural members. The shear is rotated about its axis in a wrist motion by the pumped hydraulic fluid that also powers the shear blade. It can be used in a stationary mounting or suspended from a crane. A C-shaped support for the shear was designed to pass through a small top opening of a shielded cell. The controls for manipulating the shear pass through or along the Cframe. The shear jaw opens to 5 in. in height and … more
Date: December 28, 1961
Creator: Abbatiello, A. A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Vortices associated with toroidal ion temperature gradient driven fluctuations

Description: The three nonlinear hydrodynamic equations for potential, parallel ion velocity and ion pressure used in simulations of the toroidal ion temperature gradient driven fluctuations and transport in a shear magnetic field are analyzed for coherent vortex structures. Two types of vortex structures are found: one type for weak shear that is a generalization of the usual modon vortex construction and the second type of solution for strong magnetic shear where the convective nonlinearity in the paralle… more
Date: May 1, 1992
Creator: Horton, W. (Texas Univ., Austin, TX (United States). Inst. for Fusion Studies); Jovanovic, D. (Belgrade Univ. (Yugoslavia). Inst. za Fiziku) & Rasmussen, J.J. (Association Euratom-Risoe National Lab., Roskilde (Denmark))
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Molten salt freeze seal. Final report

Description: This report documents the results of the testing performed at Sandia National Laboratory, Albuquerque, New Mexico, on the applicability of a sodium freeze seal type valve stem in a molten salt environment. The freeze seal tests consisted of cycling the valve stem at set temperature intervals, checking the temperature distribution for freeze plug location, and verifying the actuator forces. In addition to the test results, this report also documents the engineering analysis and other tasks perfo… more
Date: August 1, 1985
Creator: Corugedo, J.J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Excitation of high-n toroidicity-induced shear Alfven eigenmodes by energetic particles and fusion alpha particles in tokamaks

Description: The stability of high-n toroidicity-induced shear Alfven eigenmodes (TAE) in the presence of fusion alpha particles or energetic ions in tokamaks is investigated. The TAE modes are discrete in nature and thus can easily tap the free energy associated with energetic particle pressure gradient through wave particle resonant interaction. A quadratic form is derived for the high-n TAE modes using gyro-kinetic equation. The kinetic effects of energetic particles are calculated perturbatively using t… more
Date: July 1, 1992
Creator: Fu, G. Y. & Cheng, C. Z.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Theoretical and experimental studies of churn flow in vertical tubes. Final technical report

Description: The pattern known as churn flow is a highly unsteady pattern with stochastic features and is extremely complex. However, calculations show that for many geothermal wells the condition of churn flow consists over much of the length of the two phase zone. Furthermore, it frequently exists at the surface so that design of separation equipment and surface piping depends on the accurate modelling of this type of flow. It has been the long term purpose of this project to develop physically based mode… more
Date: January 27, 1986
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Gelled polymer systems for permeability modification in petroleum reservoirs

Description: The research program described in this report was conducted to improve the performance and predictability of in situ gelation processes designed to increase volumetric sweep efficiency of fluid displacement processes. A principal objective of this research was to develop procedures for design and evaluation of permeability modification processes. Research was conducted in three broad areas: (1) Physical and Chemical Characterization of Gelling Systems (2) In situ Gelation and (3) Mathematical M… more
Date: September 1, 1991
Creator: Willhite, G.P.; Green, D.W.; Thiele, J.L.; McCool, C.S. & Mertes, K.B.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Chemical Technology Division Unit Operations Section Monthly Progress Report, April 1962

Description: Bubble size measurements in the foam column showed that a spinnerette with 50 mu holes gave a nearly normal distribution of bubbles sizes while a coarse fritted glass gas sparger had a tail of large bubbles which did not fit the normal curve. A set of equations solvable by a finite difference technique are presented which completely describe the irreversible reaction rate of H/sub 2/ or CO with a fixed bed of CuO pellets. Radiation damage tests are in progress to evaluate plastics for the Trans… more
Date: October 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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Flow shear suppression of turbulence using externally driven ion Bernstein and Alfven waves

Description: The utilization of externally-launched radio-frequency waves as a means of active confinement control through the generation of sheared poloidal flows is explored. For low-frequency waves, kinetic Alfven waves are proposed, and are shown to drive sheared E {times} B flows as a result of the radial variation in the electromagnetic Reynolds stress. In the high frequency regime, ion Bernstein waves are considered, and shown to generate sheared poloidal rotation through the ponderomotive force. In … more
Date: January 1, 1991
Creator: Biglari, H.; Ono, M. (Princeton Univ., NJ (United States). Plasma Physics Lab.); Diamond, P.H. (California Univ., San Diego, La Jolla, CA (United States). Dept. of Physics) & Craddock, G.G. (Science Applications International Corp., San Diego, CA (United States))
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Development and utilization of new diagnostics for dense-phase pneumatic transport

Description: Dense-phase pneumatic transport is an attractive means of conveying solids. Unfortunately, because of the high solid concentrations, this transport method is a difficult regime in which to carry out detailed measurements. Hence most details of the flow are unknown. In this context, the main objective of this work is to develop probes for local measurements of solid velocity and holdup in dense gas-solid flows. Because we anticipate the recent theories of rapid granular flows will bring insight … more
Date: January 1, 1991
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Nonlinear evolution of resistive tearing mode instability with shear flow and viscosity

Description: The nonlinear evolution of the tearing mode instability with equilibrium shear flow is investigated via numerical solutions of the resistive magnetohydrodynamic equations. The two-dimensional simulations are in slab geometry, are periodic in the x-direction, and are initiated with solutions of the linearized MHD equations. The magnetic Reynolds number S was varied from 10{sup 2} to 10{sup 5}, a parameter V that measures the strength of the flow in units of the average Alfven speed was varied, a… more
Date: December 1, 1991
Creator: Ofman, L.; Morrison, P.J. (Texas Univ., Austin, TX (United States). Inst. for Fusion Studies) & Steinolfson, R.S. (Southwest Research Inst., San Antonio, TX (United States). Dept. of Space Sciences)
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Thinning and rupture of a thin liquid film on a heated surface

Description: The objective of this work continues to be the study of dynamics, stability, and rupture (including contact line motions) of thin liquid films, especially with heat and/or mass transfer. Following the publication of a comprehensive paper on thin-film stability and rupture, taking into account evaporation (condensation), thermocapillarity, surface tension, vapor recoil, van der Waals forces, and mass loss (gain), two follow-up papers have appeared. The first examines the conditions for a non-uni… more
Date: May 1, 1992
Creator: Bankoff, S.G. & Davis, S.H.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Effects of shear on vortex shedding patterns in high Reynolds number flow: an experimental study

Description: Vortex shedding has been identified as a potential major source of loading on the Ocean Thermal Energy Conversion (OTEC) Plant Cold Water Pipe (CWP). To gain a better understanding of the vortex shedding phenomena, a series of model tests has been conducted. The results of this investigation are presented. The effects of current shear on vortex shedding patterns in high Reynolds number (R/sub e/) flow around a circular cylinder used to model the OTEC CWP are addressed. Tests were conducted in a… more
Date: unknown
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Hydrodynamic design loads for the OTEC cold water pipe

Description: Ocean current and/or plant motion crossflows induce time dependent hydrodynamic loads on the OTEC cold water pipe due to vortex shedding. Design criteria were established for mean and fluctuating loads based on a review of the literature, analysis of test data acquired by SAI under a previous experimental program and an analytical extension of test results to higher Reynolds number. Baseline loads were specified for rigid cylinders in uniform flows. Modifications to the loads by current shear, … more
Date: September 1, 1978
Creator: Hove, D.; Shih, W. & Albano, E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Finite element analysis for the initiation of lamellar tearing in welded joints

Description: A numerical procedure using the finite element method is presented for predicting the initiation of lamellar tearing in fillet welded T-joints commonly employed in large structures. Starting with a prescribed geometry, the welding process is approximated by a known time-dependent volumetric heat source which simulates the arc heating and deposition of liquid metal. The transient nonlinear thermal and stress problems are then solved using finite element computer codes. Results of the elastic-pla… more
Date: January 1, 1980
Creator: Krieg, R. D. & Thomas, R. K.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Pretreatment of Kapton-coated cable for epoxy adhesion

Description: Preliminary testing of a new system for protecting bonded strain gages that will be attached to the MFTF magnets indicated falling electrical resistance to ground, attributed to the infiltration of moisture. The most likely infiltration route seemed to be along the Kapton lead cable, which has an outer surface of FEP fluorocarbon resin. Samples of the cable were pretreated with a fluorocarbon etchant, Tetra-Etch, for periods of 10, 25, and 40 s at room temperature, followed by rinsing with demi… more
Date: January 9, 1984
Creator: Carley, J. F.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Relationship between swelling and the shear modulus of irradiated metal

Description: In three alloy systems, AISI 316, the Ni-Al binary system, and the Fe-Cr-Ni ternary system, a relationship exists between the shear modulus of the unirradiated alloys and the resultant swelling observed. An alloying addition which reduces the shear modulus will subsequently reduce the irradiation-induced swelling in a solid solution hardened alloy system. The reduction in swelling is thought to be associated with the void nucleation phase of the swelling phenomenon. Thus, relative high temperat… more
Date: February 1, 1979
Creator: Bates, J. F.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Mechanical tests for validation of seismic isolation elastomer constitutive models

Description: High damping laminated elastomeric bearings are becoming the preferred device for seismic isolation of large buildings and structures, such as nuclear power plants. The key component of these bearings is a filled natural rubber elastomer. This material exhibits nonlinear behavior within the normal design range. The material damping cannot be classified as either viscous or hysteritic, but it seems to fall somewhere in between. This paper describes a series of tests that can be used to character… more
Date: January 1, 1992
Creator: Kulak, R.F. & Hughes, T.H.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Numerical simulations of collisionless drift instabilities for low-density plasmas

Description: Nonlinear behavior of the collisionless drift instabilities are studied for the universal and current driven modes by means of electrostatic particle simulations in two-and-a-half dimensions. Realistic mass ratios of the electrons to the ions are used in the simulations, where the guiding-center approximation for the electrons and the exact dynamics for the ions are employed. Several nonlinear effects including the quasilinear diffusion of the particle density, the frequency shift due to the am… more
Date: October 1, 1977
Creator: Lee, W. W.; Yau, Y. Y. K. & Okuda, H.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Structural analysis of TFTR toroidal field coil conceptual design

Description: The conceptual design evaluation of the V-shaped toroidal field coils on the Tokamak Fusion Test Reactor has been performed by detailed structural analysis with the finite element method. The innovation provided by this design and verified in this work is the capability to support toroidal field loads while simultaneously performing the function of twist restraint against the device axial torques resulting from the vertical field loads. The evaluations made for the conceptual design provide pre… more
Date: October 1, 1975
Creator: Smith, R. A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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