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Ex-vessel remote maintenance design for the Compact Ignition Tokamak

Description: The use of deuterium-tritium (D-T) fuel for operation of the Compact Ignition Tokamak (CIT) imposes a requirement for remote handling technology to carry out maintenance operations on auxiliary machine components. These operations consist of removing and repairing components such as diagnostics and radio frequency (rf) heating modules using remotely operated maintenance equipment. The major equipment that is being developed to accomplish maintenance external to the plasma chamber includes the bridge-mounted manipulator system for test cell operations, decontamination (decon) equipment, hot cell equipment, and solid rad-waste handling equipment. Wherever possible, the project will use commercially available equipment. Several areas of the maintenance system design have been addressed in fiscal year (FY) 1987. These included conceptual designs of manipulator systems, the start of a remote equipment research and development (R and D) program, and definition of the hot cell, decon, and equipment repair facility requirements. The manipulator work included investigating transporters and viewing/lighting subsystems. In each case, existing commercial units are being assessed initially, along with viable alternative approaches. R and D work also included demonstrations of remote handling operations on full-size, partial mock-ups of the CIT machine at the Oak Ridge National Laboratory (ORNL) Remote Operations and Maintenance Development Facility.
Date: January 1, 1987
Creator: Spampinato, P.T. & Macdonald, D.
Partner: UNT Libraries Government Documents Department

Development of Na/sup +/-dependent hexose transport in cultured renal epithelial cells (LLC-PK/sub 1/)

Description: A number of factors were explored to analyze how they interact to yield the increasing transport capacity in differentiating cell populations. These factors include the number of functional transporters in the population, the distribution of these transporters among the individual cells, the Na/sup +/ chemical gradient, the transmembrane potential, the pathways and activities of these pathways for efflux of glucoside, and cell-cell coupling between accumulating and non-accumulating cells. 35 references, 9 figures, 2 tables. (ACR)
Date: January 1, 1984
Creator: Weiss, E.R.; Amsler, K.; Dawson, W.D. & Cook, J.S.
Partner: UNT Libraries Government Documents Department

Far-infrared laser diagnostic on EBT and extreme far-forward laser scattering on ISX

Description: A far-infrared (FIR) laser scattering diagnostic has been installed on the ELMO Bumpy Torus (EBT) experiment, and tests conducted on the system using a TPX Bragg cell show that the system is fully functional. Scattering experiments to date have shown only small detectable signal levels during normal operation and during ion cyclotron heating (ICH) fast-wave and slow-wave propagation experiments. On the Impurity Study Experiment (ISX) the output signal from the rf amplifiers of the FIR interferometer has been spectrum analyzed and shows frequency-shifted sidebands that correspond to extreme far-forward scattering of the laser beam as it passes through the plasma. Although the scattered signal cannot be resolved spatially, the scattered intensity provides information about density fluctuation levels and MHD activity during different modes of operation. Agreement has been found with measurements made by the x-ray diagnostic and the heavy-ion beam probe.
Date: September 1, 1984
Creator: Casson, W.H.; Hutchinson, D.P.; Ma, C.H.; Staats, P.A. & Wilgen, J.B.
Partner: UNT Libraries Government Documents Department

Development of a generalized correlation for phase-velocity measurements obtained from impedance-probe pairs in two-phase flow systems. [PWR]

Description: A flag type electrical impedance probe has been developed at the Oak Ridge National Lab (ORNL) to measure liquid- and vapor-phase velocities in steam-water mixtures flowing through rod bundles. Measurements are made by utilizing the probes in pairs, installed in line, parallel to the flow direction, and extending out into the flow channel. The present study addresses performance difficulties by examining from a fundamental point of view the two-phase flow system which the impedance probes typically operate in. Specifically, the governing equations (continuity, momentum, energy) were formulated for both air-water and steam-water systems, and then subjected to a scaling analysis. The scaling analysis yielded the appropriate dimensionless parameters of significance in both kinds of systems. Additionally, with the aid of experimental data obtained at ORNL, those parameters of significant magnitude were established. As a result, a generalized correlation was developed for liquid and vapor phase velocities that makes it possible to employ the impedance probe velocity measurement technique in a wide variety of test configurations and fluid combinations.
Date: January 1, 1983
Creator: Hsu, C.T.; Keshock, E.G. & McGill, R.N.
Partner: UNT Libraries Government Documents Department

Comparison of the target-thickness dependence of the convoy electron yield and the Rydberg electron yield measured in coincidence with exit charge states in fast ion-solid collisions

Description: We have simultaneously measured the yield of convoy electrons and the yield of electrons in high Rydberg states of the projectile (n /approx gt/ 70), produced by 2MeV/u C projectiles passing through C foils, whose thicknesses range from 4--10 ug/cm/sup 2/, for incident charge states q/sub i/ = 4--6 and exit charge states q/sub e/ = 4--6. We have found that these yields exhibit similar trends as a function of foil thickness, but that, nevertheless, the ratio of the number of convoy electrons detected in coincidence with ions of exit charge state q/sub e/ to the number of electrons detected in high Rydberg states of ions with the same exit charge state is a function of foil thickness. This may be due to a broadening of the convoy electron energy spectrum with increasing foil thickness. 6 refs., 3 figs.
Date: January 1, 1988
Creator: Gaither, C.C. III; Breinig, M.; Freyou, J. & Underwood, T.A.
Partner: UNT Libraries Government Documents Department

A level playing field: Obtaining consistent cost estimates for advanced reactor designs

Description: Rules and guidelines for developing cost estimates are given which provide a means for presenting cost estimates for advanced concepts on a consistent and equitable basis. For advanced reactor designs, the scope of a cost estimate includes the plant capital cost, the operating and maintenance cost, the fuel cycle cost, and the cost of decommissioning. Each element is subdivided as is necessary to provide a common reporting format for all power plant concepts. The total generation cost is taken to be a suitable choice for a summary figure of merit. To test the application of the rules and guidelines as well as developing reference costs for current technologies, several different sized coal and pressurized water reactor plant cost estimates have been prepared. (LEW)
Date: January 1, 1987
Creator: Hudson, C.R. II; Rohm, H.H. & Humphreys, J.R. Jr.
Partner: UNT Libraries Government Documents Department

Light quark spectroscopy

Description: Recent data, in particular from LASS and GAMS, are beginning to give a rather clear picture of the spectroscopy of mesons composed of u, d, and s flavors. Details of the radial excitations are now appearing. It may become possible to identify gluonic or molecular and multiquark states by their failure of fit into the emerging q/bar q/ spectrum. An ''anti-selection rule'' for gluonic hadrons is presented. 20 refs., 3 figs., 1 tab.
Date: January 1, 1988
Creator: Close, F.E.
Partner: UNT Libraries Government Documents Department

Reduction of irradiation-induced creep by point defect trapping

Description: The theory of point defect trapping was applied to predict the effect of solutes on the steady-state dislocation climb creep rate. Vacancy loops generated in the cascades of point defect production by heavy particles were included. It is shown that the effect of vacancy loops on the creep rate is mathematically equivalent to a simultaneous reduction in the vacancy trapping rate at solutes as well as in the free point defect generation rate and recombination coefficient. These parameters are reduced by the ratio of the sink strength without vacancy loops to the total sink strength. Solute trapping and vacancy loops do not reduce the unperturbed creep rates by more than an order of magnitude for the parametric range considered.
Date: July 10, 1978
Creator: Mansur, L.K. & Wolfer, W.G.
Partner: UNT Libraries Government Documents Department

Data acquisition and control system for the K/sub 1C/-HSST experiments at the ORR

Description: Major components and primary functions of the process control system for the K/sub 1C/-HSST irradiation experiments at the Oak Ridge Research (ORR) are described. Information relative to methodology for integrating unique features of the Digital Equipment Corporation's RSX-11M Operating System with analog-to-digital and digital-to-analog hardware is presented. In particular, data flow among various real-time applications programs relative to system hardware is presented. General features of the temperature control algorithm are presented, and results that illustrate the spatial temperature distribution in the capsule achieved by the control system are included.
Date: January 1, 1984
Creator: Miller, L.F. & Hobbs, R.W.
Partner: UNT Libraries Government Documents Department

Recent advances in forward electron production studies in ion-atom and ion-solid collisions

Description: The manuscript dwells mainly on very recent progress in the field - especially on progress with experimental techniques. This discussion follows a very brief review of basics to provide appropriate orientation for those who may lack acquaintance with the field.
Date: January 1, 1984
Creator: Sellin, I.A.; Elston, S.B. & Berry, S.D.
Partner: UNT Libraries Government Documents Department

The impact of confinement scaling on ITER (International Thermonuclear Experimental Reactor) parameters

Description: Energy confinement scaling is a major concern in the design of the International Thermonuclear Experimental Reactor (ITER). The existing database for tokamaks can be fitted with a number of different confinement scaling expressions that have similar degrees of approximation. These scaling laws predict confinement times for ITER that vary by over an order of magnitude. The uncertainties in the form and magnitude of these scaling laws must be substantially reduced before the plasma performance of ITER can be predicted with adequate reliability. The TETRA systems code is used to calculate the dependence of major ITER parameters on the scaling laws currently in use. Design constraints of interest in the present phase of ITER consideration are used, and the minimum-cost devices arising from these constraints are reviewed. 9 refs., 13 figs., 4 tabs.
Date: September 1, 1988
Creator: Reid, R.L.; Galambos, J.D. & Peng, Y.K.M.
Partner: UNT Libraries Government Documents Department

Observation of a critical angular momentum for deep inelastic processes with light heavy ions

Description: Studies of collisions between nuclei have shown that the large incoming orbital angular momenta play an important role in systems where Coulomb and centrifugal repulsion for the dominant (near grazing) partial waves are of comparable magnitude (A/sub p/,A/sub t/ < 40). The kinetic energy of the fully damped fragments contains significant centrifugal energy contributions. Recent measurements have shown that the yield of fragments from strongly damped processes dominates the spectra at backward angles, and the angular distributions associated with this yield indicate that the fragments emerge from a long-lived rotating dinuclear complex (orbiting). These measurements at backward angles provide a means for studying the products from deep inelastic processes in the absence of contributions from quasielastic processes. In our study of deep inelastic processes in /sup 28/Si + /sup 12/C at backward angles we show here results which demonstrate that the orbital angular momentum of the rotating dinuclear system formed in this collision reaches a critical value beyond which it ceases to increase with increasing bombarding energy.
Date: March 1, 1984
Creator: Thornton, S.T.; Parks, R.L.; Shapira, D.; Schull, D.; Ford, J.L.C. Jr. & Shivakumar, B.
Partner: UNT Libraries Government Documents Department

High-throughput continuous cryopump

Description: A cryopump with a unique method of regeneration which allows continuous operation at high throughput has been constructed and tested. Deuterium was pumped continuously at a throughput of 30 Torr.L/s at a speed of 2000 L/s and a compression ratio of 200. Argon was pumped at a throughput of 60 Torr.L/s at a speed of 1275 L/s. To produce continuous operation of the pump, a method of regeneration that does not thermally cycle the pump is employed. A small chamber (the ''snail'') passes over the pumping surface and removes the frost from it either by mechanical action with a scraper or by local heating. The material removed is topologically in a secondary vacuum system with low conductance into the primary vacuum; thus, the exhaust can be pumped at pressures up to an effective compression ratio determined by the ratio of the pumping speed to the leakage conductance of the snail. The pump, which is all-metal-sealed and dry and which regenerates every 60 s, would be an ideal system for pumping tritium. Potential fusion applications are for mpmp limiters, for repeating pneumatic pellet injection lines, and for the centrifuge pellet injector spin tank, all of which will require pumping tritium at high throughput. Industrial applications requiring ultraclean pumping of corrosive gases at high throughput, such as the reactive ion etch semiconductor process, may also be feasible.
Date: January 1, 1986
Creator: Foster, C.A.
Partner: UNT Libraries Government Documents Department

Mechanical Property Measurements on Ion-Irradiated Metals

Description: A recently developed mechanical properties microprobe (MPM) has been used to investigate strength and elastic modulus changes in ion-irradiated metals. The indenter load and its displacement are simultaneously monitored while the indentation is being made and also during unloading. Microindentation hardness measurements have been performed on ion-irradiated copper and Cu-0.15% Zr (AMZIRC). The depth dependence of the ion damage has been investigated in selected specimens which were prepared using a cross-section technique. This procedure allows a direct comparison to be made of hardness data from different irradiation depths while the indent size is held constant. The displacement damage associated with ion irradiation caused either hardening or softening, depending on the irradiation conditions and the material.
Date: August 1, 1986
Creator: Zinkle, S. J. & Oliver, W. C.
Partner: UNT Libraries Government Documents Department

Application of scanning electron microscopy and ultraviolet fluorescence to a study of Chattanooga Shale

Description: Microanalytical techniques such as scanning electron microscopy, energy-dispersive x-ray analysis, and electron-beam microprobe analysis have been shown to be ideal for determining the host phases of the minor and trace elements in the Chattanooga shale. Positive correlations were found between pyrite and organic constituents. However, these observations provided no evidence that microorganisms acted as hosts for pyrite framboids. Interestingly, appreciable organic sulfur is still present, suggesting that the sulfur used for the formation of pyrite must have been derived mostly from other sources. It may be that the sulfate-reducing bacteria had an affinity for organic matter and that the organic fragments acted as substrates for pyrite growth.
Date: January 1, 1982
Creator: Harris, L.A.; Kopp, O.C. & Crouse, R.S.
Partner: UNT Libraries Government Documents Department

Nondestructive assay of spent boiling water reactor fuel by active neutron interrogation

Description: Spent boiling water reactor (BWR) fuel from Dresden I was assayed for total fissile mass, using the active neutron interrogation method. The nondestructive assay (NDA) system used has four Sb-Be sources for interrogation of the fuels; the induced fission neutrons from the fuel are counted by four lead-shielded methane-filled proportional counters biased above the energy of the source neutrons. Spent fuel rods containing 9 kg of heavy metal were chopped into 5-cm segments and loaded into three 1-liter cans. The three cans were assayed in seven combinations of one, two, or three cans, enabling an evaluation of the precision and accuracy of the NDA system for different amounts of fissile material. The fissile mass in each combination was determined by comparing the induced-fission-neutron counts with the counts obtained from a known standard comprising chopped segments of unirradiated Dresden fuel. These masses were compared to the masses determined by chemical analyses of the spent fuel. The results from the nondestructive assays agreed with results from the chemical analyses to within 2 to 3%. Similar agreement was obtained when two combinations of canned spent fuel were used as standards for the nondesctuctive assays. The assay of BWR spent fuel served as a test of the NDA system which was developed at the Oak Ridge National Laboratory for the assay of spent liquid metal fast breeder reactor (LMFBR) fuel subassemblies at the heat-end of a reprocessing plant. Results of previous experiments and calculations reported earlier using simulated LMFBR fuel subassemblies indicated that the NDA system can measure the fissile masses of spent fuel subassemblies to within an accuracy of 3%. Results of the assays of spent BWR fuel reported herein support this conclusion.
Date: January 1, 1981
Creator: Blakeman, E.D.; Ricker, C.W.; Ragan, G.L.; Difilippo, F.C. & Slaughter, G.G.
Partner: UNT Libraries Government Documents Department

Charged-particle calculations using Boltzmann transport methods

Description: Several aspects of radiation damage effects in fusion reactor neutron and ion irradiation environments are amenable to treatment by transport theory methods. In this paper, multigroup transport techniques are developed for the calculation of charged particle range distributions, reflection coefficients, and sputtering yields. The Boltzmann transport approach can be implemented, with minor changes, in standard neutral particle computer codes. With the multigroup discrete ordinates code, ANISN, determination of ion and target atom distributions as functions of position, energy, and direction can be obtained without the stochastic error associated with atomistic computer codes such as MARLOWE and TRIM. With the multigroup Monte Carlo code, MORSE, charged particle effects can be obtained for problems associated with very complex geometries. Results are presented for several charged particle problems. Good agreement is obtained between quantities calculated with the multigroup approach and those obtained experimentally or by atomistic computer codes.
Date: January 1, 1981
Creator: Hoffman, T.J.; Dodds, H.L. Jr.; Robinson, M.T. & Holmes, D.K.
Partner: UNT Libraries Government Documents Department

Influence of fuel vibration on PWR neutron noise associated with core barrel motion

Description: Ex-core neutron detector noise has been utilized to monitor core support barrel (CSB) vibrations. In order to observe long-term changes, noise signals at Sequoyah-1 were monitored continuously during the whole first fuel cycle and part of the second cycle. Results suggest that neutron noise measurements performed infrequently may not provide adequate surveillance of the CSB because it may be difficult to separate noise amplitude changes due solely to CSB motion from changes caused by fuel motion and burnup. (DLC)
Date: January 1, 1984
Creator: Sweeney, F.J. & March-Leuba, J.
Partner: UNT Libraries Government Documents Department

Continuum capture in the three-body problem

Description: The three-body problem, especially the problem of electron capture to the continuum in heavy particle collisions is reviewed. Major topics covered include: second born-induced asymmetry in electron capture to the continuum; historical context, links to other tests of atomic scattering theory; experiments characterizing the velocity distribution of ECC electrons; other atomic physics tests of high velocity Born expansions; atom capture; capture by positrons; and pion capture to the continuum. (GHT)
Date: January 1, 1980
Creator: Sellin, I A
Partner: UNT Libraries Government Documents Department

Optimal filtering, parameter tracking, and control of nonlinear nuclear reactors

Description: This paper presents a new formulation of a class of nonlinear optimal control problems in which the system's signals are noisy and some system parameters are changing arbitrarily with time. The methodology is validated with an application to a nonlinear nuclear reactor model. A variational technique based on Pontryagin's Maximum Principle is used to filter the noisy signals, estimate the time-varying parameters, and calculate the optimal controls. The reformulation of the variational technique as an initial value problem allows this microprocessor-based algorithm to perform on-line filtering, parameter tracking, and control.
Date: June 24, 1988
Creator: March-Leuba, C.; March-Leuba, J. & Perez, R.B.
Partner: UNT Libraries Government Documents Department

Automatic camera tracking for remote manipulators

Description: The problem of automatic camera tracking of mobile objects is addressed with specific reference to remote manipulators and using either fixed or mobile cameras. The technique uses a kinematic approach employing 4 x 4 coordinate transformation matrices to solve for the needed camera PAN and TILT angles. No vision feedback systems are used, as the required input data are obtained entirely from position sensors from the manipulator and the camera-positioning system. All hardware requirements are generally satisfied by currently available remote manipulator systems with a supervisory computer. The system discussed here implements linear plus on/off (bang-bang) closed-loop control with a +-2-deg deadband. The deadband area is desirable to avoid operator seasickness caused by continuous camera movement. Programming considerations for camera control, including operator interface options, are discussed. The example problem presented is based on an actual implementation using a PDP 11/34 computer, a TeleOperator Systems SM-229 manipulator, and an Oak Ridge National Laboratory (ORNL) camera-positioning system. 3 references, 6 figures, 2 tables.
Date: July 1, 1984
Creator: Stoughton, R.S.; Martin, H.L. & Bentz, R.R.
Partner: UNT Libraries Government Documents Department

Angular distributions of very low energy recoil ions

Description: We present the first measurements of the angular distribution of recoil ions near 90/sup 0/ with respect to the incident projectile direction. Beams of 22.5 and 33 MeV chlorine ions (incident charge states q =4,5,8) have been used as ''hammer'' beams incident on Ne atoms. We confirm the long standing assumption that these recoil ions are ejected preferentially at angles near 90/sup 0/ with respect to the primary beam direction and with energies typically less than 5 eV. Recoil ions ejected around 90/sup 0/ have an energy distribution appreciably wider than those ejected at either larger or smaller angles. 9 refs., 6 figs.
Date: January 1, 1986
Creator: Gonzalez Lepera, C.E.; Breinig, M.; Burgdoerfer, J.; DeSerio, R.; Elston, S.B.; Gibbons, J.P. et al.
Partner: UNT Libraries Government Documents Department