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An introduction to acceleration mechanisms

Description: This paper discusses the acceleration of charged particles by electromagnetic fields, i.e., by fields that are produced by the motion of other charged particles driven by some power source. The mechanisms that are discussed include: Ponderamotive Forces, Acceleration, Plasma Beat Wave Acceleration, Inverse Free Electron Laser Acceleration, Inverse Cerenkov Acceleration, Gravity Acceleration, 2D Linac Acceleration and Conventional Iris Loaded Linac Structure Acceleration. (LSP)
Date: May 1, 1987
Creator: Palmer, R.B.
Partner: UNT Libraries Government Documents Department

A safeguards verification technique for solution homogeneity and volume measurements in process tanks

Description: A safeguards verification technique is being developed for determining whether process-liquid homogeneity has been achieved in process tanks and for authenticating volume-measurement algorithms involving temperature corrections. It is proposed that, in new designs for bulk-handling plants employing automated process lines, bubbler probes and thermocouples be installed at several heights in key accountability tanks. High-accuracy measurements of density using an electromanometer can now be made which match or even exceed analytical-laboratory accuracies. Together with regional determination of tank temperatures, these measurements provide density, liquid-column weight and temperature gradients over the fill range of the tank that can be used to ascertain when the tank solution has reached equilibrium. Temperature-correction algorithms can be authenticated by comparing the volumes obtained from the several bubbler-probe liquid-height measurements, each based on different amounts of liquid above and below the probe. The verification technique is based on the automated electromanometer system developed by Brookhaven National Laboratory (BNL). The IAEA has recently approved the purchase of a stainless-steel tank equipped with multiple bubbler and thermocouple probes for installation in its Bulk Calibration Laboratory at IAEA Headquarters, Vienna. The verification technique is scheduled for preliminary trials in late 1987.
Date: January 1, 1987
Creator: Suda, S. & Franssen, F.
Partner: UNT Libraries Government Documents Department

Coherence in CePd/sub 3/

Description: This paper presents results of resistivity and susceptibility measurements on CePd/sub 3/ and its alloys which support the existence of a third significant temperature, T* = 40K. Anomalous pressure dependence of rho(T) occurs and nonmagnetic impurities cause large increases in rho(T) on this scale, which is distinct from and smaller than the scale T/sub max/ over which coherence first appears. Evidence is given that the magnetic form factor anomaly known to exist in CePd/sub 3/ arises on the same scale T* suggesting that the 5d spin susceptibility which is responsible for the form factor anomaly is connected with the low temperature transport anomalies. The discussion is limited to the relationship of these results to other experimental measurements in CePd/sub 3/. In particular, we stress the relationship of these results to those of recent optical conductivity measurements which show that the quasi-particle effective mass is strongly renormalized at low temperatures. This occurs over a temperature scale proposed for T*.
Date: January 1, 1987
Creator: Lawrence, J.M.; Chen, Y.Y. & Thompson, J.D.
Partner: UNT Libraries Government Documents Department

Performance of low upper-shelf material under pressurized-thermal-shock loading (PTSE-2)

Description: The second pressurized-thermal-shock experiment (PTSE-2) of the Heavy-Section Steel Technology Program was conceived to investigate fracture behavior of steel with low ductile-tearing resistance. PTSE-2 was designed primarily to reveal the interaction of ductile and brittle modes of fracture and secondarily to investigate the effects of warm prestressing. A test vessel was prepared by inserting a crack-like flaw of well-defined geometry on the outside surface of the vessel. The flaw was 1 m long by approx.15 mm deep. The instrumented vessel was placed in a test facility in which it was initially heated to a uniform temperature and was then concurrently cooled on the outside and pressurized on the inside. These actions produced an evolution of temperature, toughness, and stress gradients relative to the prepared flaw that was appropriate to the planned objectives. The experiment was conducted in two separate transients, each one starting with the vessel nearly isothermal. The first transient induced a warm prestressed state, during which K/sub I/ first exceeded K/sub Ic/. This was followed by repressurization until a cleavage fracture propagated and arrested. The final transient was designed to produce and investigate a cleavage crack propagation followed by unstable tearing. During this transient the fracture events occurred as had been planned. 7 refs., 13 figs., 2 tabs.
Date: January 1, 1987
Creator: Bryan, R.H.; Bass, B.R.; Bolt, S.E.; Bryson, J.W.; Corwin, W.R.; Nanstad, R.K. et al.
Partner: UNT Libraries Government Documents Department

Fossil Energy Materials Program conference proceedings

Description: The US Department of Energy Office of Fossil Energy has recognized the need for materials research and development to assure the adequacy of materials of construction for advanced fossil energy systems. The principal responsibility for identifying needed materials research and for establishing a program to address these needs resides within the Office of Technical Coordination. That office has established the Advanced Research and Technology Development (AR and TD) Fossil Energy Materials Program to fulfill that responsibility. In addition to the AR and TD Materials Program, which is designed to address in a generic way the materials needs of fossil energy systems, specific materials support activities are also sponsored by the various line organizations such as the Office of Coal Gasification. A conference was held at Oak Ridge, Tennessee on May 19-21, 1987, to present and discuss the results of program activities during the past year. The conference program was organized in accordance with the research thrust areas we have established. These research thrust areas include structural ceramics (particularly fiber-reinforced ceramic composites), corrosion and erosion, and alloy development and mechanical properties. Eighty-six people attended the conference. Papers have been entered individually into EDB and ERA. (LTN)
Date: August 1, 1987
Creator: Judkins, R.R. (comp.)
Partner: UNT Libraries Government Documents Department

Subcommittee for MHD theory: Status report. [Viewgraphs]

Description: This progress report contains viewgraphs on the limits of the beta value and the safety factor for tokamak magnetohydrodynamic flows. (LSP)
Date: January 1, 1987
Creator: Dory, R.A.
Partner: UNT Libraries Government Documents Department

New theory for competing interactions and microstructures in partially-ordered (liquid-crystalline) phases

Description: A summary of results from a unique statistical-physics theory to predict and explain competing interactions and resulting microstructures in some partially-ordered (in this case, liquid-crystalline (LC)) phases is presented. The static aspects of both partial orientational and partial positional ordering of the molecules into various microstructures in these phases (including the incommensurate smectic-Ad phase) can be understood in terms of various competing interactions (both entropic and energetic) involved in the packing together of the different molecular sub-units at given pressures and temperatures. These microstructures are predicted and explained (using no ad hoc or arbitrarily adjustable parameter) as a function of molecule chemical structure (including lengths and shapes (from bond lengths and angles), intramolecular rotations, site-site polarizabilities and pair potentials, dipole moments, etc). Theoretical results are presented for the nematic, re-entrant nematic, smectic-Ad, and smectic-Al LC phases and the isotropic phase.
Date: January 1, 1987
Creator: Dowell, F.
Partner: UNT Libraries Government Documents Department

MINET (Momentum Integral NETwork) analysis of MHTGR (Modular High Temperature Gas-Cooled Reactor) moisture-ingress transient

Description: The transient which involved a steam-generator tube leak and the ingress of moisture into the primary coolant system of the standard Modular Modular High Temperature Gas-Cooled Reactor (MHTGR) is analyzed by using the MINET (Momentum Integral NETwork) computer code. The analysis provides detailed information on the effect of power excursion on transient system pressures and temperatures. It is concluded that during the short term transient period the moisture ingress presents no threat to the integrity of the fuel elements and does not lead to pressures which would cause relief valve opening and fission product release.
Date: January 1, 1987
Creator: Yang, J.W.; Kroeger, P.G.; Van Tuyle, G.J. & Aronson, A.L.
Partner: UNT Libraries Government Documents Department

Microstructural characterization of irradiated PWR steels using the atom probe field-ion microscope

Description: Atom probe field-ion microscopy has been used to characterize the microstructure of a neutron-irradiated A533B pressure vessel steel weld. The atomic spatial resolution of this technique permits a complete structural and chemical description of the ultra-fine features that control the mechanical properties to be made. A variety of fine scale features including roughly spherical copper precipitates and clusters, spherical and rod-shaped molybdenum carbide and disc-shaped molybdenum nitride precipitates were observed to be inhomogeneously distributed in the ferrite. The copper content of the ferrite was substantially reduced from the nominal level. A thin film of molybdenum carbides and nitrides was observed on grain boundaries in addition to a coarse copper-manganese precipitate. Substantial enrichment of manganese and nickel were detected at the copper-manganese precipitate-ferrite interface and this enrichment extended into the ferrite. Enrichment of nickel, manganese and phosphorus were also measured at grain boundaries.
Date: August 1, 1987
Creator: Miller, M.K. & Burke, M.G.
Partner: UNT Libraries Government Documents Department

Nitrogen at very high pressure

Description: High-pressure results for nitrogen are reviewed and discussed in terms of phenomena that occur at extreme conditions.
Date: July 1, 1987
Creator: Nellis, W.J.
Partner: UNT Libraries Government Documents Department

Stress-corrosion cracking susceptibility of V-15Cr-5Ti in pressurized water at 288/sup 0/C

Description: The stress-corrosion cracking susceptibility of V-15Cr-5Ti in pressurized water at 288/sup 0/C has been evaluated by means of constant extension rate tensile (CERT) tests in a refreshed autoclave system. The test environments included high-purity water as well as water containing SO/sub 4//sup 2 -/ and NO/sub 3//sup -/ impurities at a concentration of 10 wppM. Strain rates from 1 x 10/sup -6/ to 5 x 10/sup -8/ s/sup -1/ were employed, and dissolved oxygen levels ranged from <0.005 to 7.9 wppM. Test times were from 3.2 to 619 h. No stress corrosion cracking was observed under any of the test conditions. These results were analyzed using measured electrochemical potentials, available Pourbaix diagram information, and the observed oxidation behavior. 7 refs., 5 figs., 1 tab.
Date: July 1, 1987
Creator: Diercks, D.R. & Smith, D.L.
Partner: UNT Libraries Government Documents Department

Mass spectrometry studies of fission product behavior: 2, Gas phase species

Description: Revaporization of fission products from reactor system surfaces has become a complicating factor in source term definition. Critical to this phenomena is understanding the nature and behavior of the vapor phase species. This study characterizes the stability of the CsI . CsOH vapor phase complex. Vapor pressures were measured with a mass spectrometer. Thermodynamic data were obtained for CsOH(g), Cs/sub 2/(OH)/sub 2/(g), CsI(g), Cs/sub 2/I/sub 2/(g) and CsI . CsOH(g). Activity coefficients were derived for the CsI-CsOH system. The relative ionization cross section of CsOH is about ten times the cross section of CsI(g). CsI . CsOH fragments to Cs/sub 2/OH/sup +/ and an iodine atom. 17 refs., 4 figs., 6 tabs.
Date: January 1, 1987
Creator: Blackburn, P.E. & Johnson, C.E.
Partner: UNT Libraries Government Documents Department

Performance evaluation of PEP

Description: An investigation of collective effects has been undertaken to assess the possibilities for using the low emittance operating mode of the PEP storage ring as a dedicated source of synchrotron radiation. Beam current limitations associated with longitudinal and transverse instabilities, and the expected emittance growth due to intrabeam scattering have been studied as a function of beam energy. Calculations of the beam lifetime due to Touschek and gas scattering are presented, and the growth times of coupled-bunch instabilities are estimated. In general, the results are encouraging, and no fundamental problems have been uncovered. It appears that beam currents up to about 10 mA per bunch should be achievable, and that the emittance growth is not a severe problem at an energy of about 8 GeV. A feedback system to deal with coupled-bunch instabilities is likely to be required. 7 refs., 13 figs.
Date: October 1, 1987
Creator: Zisman, M.S.
Partner: UNT Libraries Government Documents Department

Suppression of x-rays generated by runaway electrons in ATF

Description: X-ray emission from runaway electrons on ATF is a serious issue. Runaway suppression techniques used on Heliotron-E are not adequate for ATF. Three approaches have been developed to suppress runaway production. Monitoring devices have been installed in occupied areas and personnel access and exposure will be limited. Additional shielding will be added as required. These systems will be ready for installation and testing on ATF prior to commissioning or first plasma operation.
Date: January 1, 1987
Creator: Rasmussen, D. A.; England, A. C.; Eberle, C. C.; Devan, W. R.; Harris, J. H.; Jernigan, T. C. et al.
Partner: UNT Libraries Government Documents Department

The Argonne PIIECR ion source project status

Description: The first beam from the Argonne PIIECR ion source was achieved on October 21, 1987. The major construction effort for both the source and high voltage platform is finished but a number of subsystems remain to be completed such as the remote control system and a gas handling system. Early source operation indicates that the major elements are functioning as designed, with the exception of the extraction high voltage insulation. Beam has been accelerated off the high voltage platform to a temporary atomic physics experimental area. The source is a major element in the ATLAS Positive Ion Injector project. 4 refs., 5 figs., 1 tab.
Date: January 1, 1987
Creator: Pardo, R.C. & Billquist, P.J.
Partner: UNT Libraries Government Documents Department

Proceedings of the international workshop on engineering design of next step reversed field pinch devices

Description: These Proceedings contain the formal contributed papers, the workshop papers and workshop summaries presented at the International Workshop on Engineering Design of Next Step RFP Devices held at Los Alamos, July 13-17, 1987. Contributed papers were presented at formal sessions on the topics: (1) physics overview (3 papers); (2) general overview (3 papers); (3) front-end (9 papers); (4) computer control and data acquisition (1 paper); (5) magnetics (5 papers); and (6) electrical design (9 papers). Informal topical workshop sessions were held on the topics: (1) RFP physics (9 papers); (2) front-end (7 papers); (3) magnetics (3 papers); and (4) electrical design (1 paper). This volume contains the summaries written by the Chairmen of each of the informal topical workshop sessions. The papers in these Proceedings represent a significant review of the status of the technical base for the engineering design of the next step RFP devices being developed in the US, Europe, and Japan, as of this date.
Date: November 1, 1987
Creator: Thomson, D.B. (comp.)
Partner: UNT Libraries Government Documents Department

Recent progress on the Los Alamos Aurora ICF (inertial confinement fusion) laser system

Description: Aurora is the Los Alamos short-pulse, high-power, krypton-fluoride laser system. It serves as an end-to-end technology demonstration prototype for large-scale ultraviolet laser systems for short wavelength inertial confinement fusion (ICF) investigations. The system is designed to employ optical angular multiplexing and serial amplification by electron-beam-driven KrF laser amplifiers to deliver stacked, 248-nm, 5-ns duration multikilojoule laser pulses to ICF-relevant targets. This paper presents a summary of the Aurora system and a discussion of the progress achieved in the construction and integration of the laser system. We concentrate on the main features of the following major system components: front-end lasers, amplifier train, multiplexer, optical relay train, demultiplexer, and the associated optical alignment system. During the past year, two major construction and integration tasks have been accomplished. The first task is the demonstration of 96-beam multiplexing and amplified energy extraction, as evidenced by the integrated operation of the front end, the multiplexer (12-fold and 8-fold encoders), the optical relay train, and three electron-beam-driven amplifiers. The second task is the assembly and installation of the demultiplexer optical hardware, which consists of over 300 optical components ranging in size from several centimeters square to over a meter square. 13 refs., 13 figs.
Date: January 1, 1987
Creator: Rosocha, L.A. & Blair, L.S.
Partner: UNT Libraries Government Documents Department

Resistivity of EuBa/sub 2/(Cu/sub 1-y/Zn/sub y/)/sub 3/O/sub x/ as a function of temperature, magnetic field, pressure and Zn concentration

Description: We report electrical resistance and magnetoresistance measurements on EuBa/sub 2/(Cu/sub 1-y/Zn/sub y/)/sub 3/O/sub x/ under pressure to 17 kbar. With Zn substitution, T/sub c/ is depressed rapidly (approx.19 K/at.% Zn) and there are qualitative changes in the temperature and field response of the resistance. Pressure drives the Zn-substituted samples toward undoped EuBa/sub 2/Cu/sub 3/O/sub x/ behavior. Analysis of the temperature dependent resistance for y = 0.05 and P = O, together with Hall effect and thermopower data, suggests that the suppression of superconductivity may arise from weak three-dimensional localization promoted by Coulomb interactions.
Date: January 1, 1987
Creator: Borges, H.A.; Wells, G.L.; Cheong, S.W.; Kwok, R.S.; Thompson, J.D.; Fisk, Z. et al.
Partner: UNT Libraries Government Documents Department

Detection and characterization of flaws in segments of light water reactor pressure vessels

Description: Studies have been conducted to determine flaw density in segments cut from light water reactor (LWR) pressure vessels as part of the Oak Ridge National Laboratory's Heavy-Section Steel Technology (HSST) Program. Segments from the Hope Creek Unit 2 vessil and the Pilgrim Unit 2 Vessel were purchased from salvage dealers. Hope Creek was a boiling water reactor (BWR) design and Pilgrim was a pressurized water reactor (PWR) design. Neither were ever placed in service. Objectives were to evaluate these LWR segments for flaws with ultrasonic and liquid penetrant techniques. Both objectives were successfully completed. One significant indication was detected in a Hope Creek seam weld by ultrasonic techniques and characterized by further analyses terminating with destructive correlation. This indication (with a through-wall dimension of approx.6 mm (approx.0.24 in.)) was detected in only 3 m (10 ft) of weldment and offers extremely limited data when compared to the extent of welding even in a single pressure vessel. However, the detection and confirmation of the flaw in the arbitrarily selected sections implies the Marshall report estimates (and others) are nonconservative for such small flaws. No significant indications were detected in the Pilgrim material by ultrasonic techniques. Unfortunately, the Pilgrim segments contained relatively little weldment; thus, we limited our ultrasonic examinations to the cladding and subcladding regions. Fluorescent liquid penetrant inspection of the cladding surfaces for both LWR segments detected no significant indications (i.e., for a total of approximately 6.8 m/sup 2/ (72 ft/sup 2/) of cladding surface).
Date: January 1, 1987
Creator: Cook, K.V.; Cunningham, R.A. Jr. & McClung, R.W.
Partner: UNT Libraries Government Documents Department

Summary of HSST wide-plate crack-arrest tests and analyses

Description: Eleven wide-plate crack-arrest tests have been completed to date, seven utilizing specimens fabricated from A533B class 1 material (WP-1 series), and four fabricated from a low upper-shelf base material (WP-2 series). With the exception of one test in the WP-1 series and two tests in the WP-2 series which utilized 152-mm-thick specimens, each test utilized a single-edge notched (SEN) plate specimen 1 by 1 by 0.1 m that was subjected to a linear thermal gradient along the plane of crack propagation. Test results exhibit an increase in crack-arrest toughness with temperature, with the rate of increase becoming greater as the temperature increases. When the wide-plate test results are combined with other large-specimen results (Japanese ESSO, thermal-shock experiments and pressurized-thermal-shock experiments), the data show a consistent trend in which the K/sub Ia/ data extends above the limit provided in ASME Section XI.
Date: January 1, 1987
Creator: Naus, D.J.; Bass, B.R.; Keeney-Walker, J.; Fields, R.J.; deWit, R. & Low, S.R. III
Partner: UNT Libraries Government Documents Department

Reinjection into geothermal reservoirs

Description: Reinjection of geothermal wastewater is practiced as a means of disposal and for reservoir pressure support. Various aspects of reinjection are discussed, both in terms of theoretical studies as well as specific field examples. The discussion focuses on the major effects of reinjection, including pressure maintenance and chemical and thermal effects. (ACR)
Date: August 1, 1987
Creator: Bodvarsson, G.S. & Stefansson, V.
Partner: UNT Libraries Government Documents Department

Fabrication and installation of the vacuum vessel for the Advanced Toroidal Facility

Description: The vacuum vessel for the Advanced Toroidal Facility (ATF) has been completed and installed in the facility. The vessel fabrication has involved many unique methods to correct unanticipated problems. The primary fabrication concern has been to correct for dimensional inconsistency so that the vessel would fit into the closely nested helical coil set. The vessel has been installed and the remainder of the facility components are being assembled.
Date: January 1, 1987
Creator: Chipley, K.K.
Partner: UNT Libraries Government Documents Department

Effects of commercial cladding on the fracture behavior of pressure vessel steel plates

Description: The objective of this program is to determine the effect, if any, of stainless steel cladding upon the propagation of small surface cracks subjected to stress states similar to those produced by thermal shock conditions. Preliminary results from testing at temperatures 10/sup 0/ and 60/sup 0/C below NDT have shown that (1) a tough surface layer (cladding and/or HAZ) has arrested running flaws under conditions where unclad plates have ruptured, and (2) the residual load-bearing capacity of clad plates with large subclad flaws significantly exceeded that of an unclad plate.
Date: January 1, 1987
Creator: Iskander, S.K.; Alexander, D.J.; Bolt, S.E.; Cook, K.V.; Corwin, W.R.; Oland, B.C. et al.
Partner: UNT Libraries Government Documents Department