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Recovery of deformed and hydrogen-charge palladium (open access)

Recovery of deformed and hydrogen-charge palladium

Positron lifetime and Doppler-broadening studies made at 300 K have been used to investigate the interaction between interstitial hydrogen and lattice defects in deformed Pd. Specimens were charged with hydrogen at 300 K to levels up to 0.1%. The presence of hydrogen was found to have no effect on the recovery curves of Pd upon annealing to 400/sup 0/C. By 400/sup 0/C the values for both lifetime and Doppler-broadening for both cold worked and cold worked plus hydrogen were below the values obtained for annealed pure Pd. This can be interpreted as gaseous-impurity-trapped vacancies being present after the 1200/sup 0/C anneal, but being swept away by the dislocation microstructure recovery between 200 to 400/sup 0/C.
Date: January 1, 1982
Creator: Snead, C. L. Jr.; Lynn, K. G. & Lynch, J. F.
Object Type: Article
System: The UNT Digital Library
Excitation of giant resonances via direct reactions (open access)

Excitation of giant resonances via direct reactions

Experimental measurements of electric giant multipole resonances are discussed. The parameters of the giant quadrupole resonance are now firmly established by an extensive set of measurements. The GQR is providing a significant influence in other areas of nuclear physics. The monopole resonance has now been established and its observation has provided the first direct measure of the nuclear compressibility. A strong case for the existence of a giant octupole resonance is now being made through a variety of hadron reactions. However, the supply of giant multipole resonances has not been exhausted. The newer techniques such as higher energy proton scattering, charge exchange reactions, heavy-ion scattering and pion reactions offer considerable hope for identifying new resonances during the next few years.
Date: January 1, 1982
Creator: Bertrand, F.E.
Object Type: Article
System: The UNT Digital Library
Picotron 100 streak tubes as a 150-channel photometer (open access)

Picotron 100 streak tubes as a 150-channel photometer

The characterization of a streak camera based upon Picotron 100 tube types is given. Both a large (30 cm 1 x 10 cm dia.) and a small (18 cm 1 x 5 cm dia.) version of this design has been tested. Over 150 channels of information are simultaneously time resolved with system S.N.R. of 3 at 100 picosecond time resolution without post intensification. Absolute photometric evaluation is given in the dynamic mode, i.e. while operating in the picosecond time domain. Such quantitative data has been lacking in the past, particularly for multiple channel applications.
Date: January 1, 1982
Creator: Majumdar, S.; Weiss, P.B. & Black, J.P.
Object Type: Article
System: The UNT Digital Library
HVDC-AC system interaction from AC harmonics. Volume 1. Harmonic impedance calculations. Final report (open access)

HVDC-AC system interaction from AC harmonics. Volume 1. Harmonic impedance calculations. Final report

Improved methods are needed to characterize ac system harmonic behavior for ac filter design for HVDC systems. The purpose of this General Electric Company RP1138 research is to evaluate the present filter design practice and to investigate methods for calculating system harmonic impedances. An overview of ac filter design for HVDC systems and a survey of literature related to filter design have been performed. Two methods for calculating system harmonic impedances have been investigated. In the measurement method, an instrumentation system for measuring system voltage and current has been assembled. Different schemes of using the measurements to calculate system harmonic impedances have been studied. In the analytical method, a procedure to include various operating conditions has been proposed. Computer programs for both methods have been prepared, and the results of the measurement and analytical methods analyzed. A conclusion of the project is that the measurement and analytical methods both provided reasonable results. There are correlations between the measured and analytical results for most harmonics, although there are discrepancies between the assumptions used in the two methods. A sensitivity approach has been proposed to further correlate the results. From the results of the analysis, it is recommended that both methods should …
Date: September 1, 1982
Creator: Breuer, G D; Chow, J H; Lindh, C B; Miller, N W; Numrich, F H; Price, W W et al.
Object Type: Report
System: The UNT Digital Library
Stress analysis of MFTF-B getter system bellows. Final report (open access)

Stress analysis of MFTF-B getter system bellows. Final report

The MFTF-B design includes a retractable getter system. Eight getter assemblies are planned (4 in each end plug). Electrically heated Ti wires are mounted on a telescoping insertion mechanism and, between machine shots (pulses), are extended into the chamber in the vicinity of inward-facing water-cooled magnet liners. During the shots, the sublimators must be withdrawn because they will intrude into plasma and diagnostic space. Each of the getter assemblies will be mounted on the exterior of the vacuum vessel. Bellows are used to keep essentially all of the mechanism isolated from the vessel vacuum. The bellows come in two sizes (8.25'' O.D. and 14'' O.D.). The smaller of the two bellows has been qualified by testing up to 94,000 cycles by empirically adjusting details of the bellow design (geometry and thickness). The process required 12 different test samples and took over a one-year period to accomplish. The bellows consistently failed in the inside diameter weld heat-affected zone. Results from stress analysis studies are presented.
Date: April 1, 1982
Creator: Tokarz, F. J.; Johnson, J. J.; Mukherjee, A. N. & Dalder, E. N.
Object Type: Report
System: The UNT Digital Library
Laser-plasma interaction experiments at laser wavelengths of 1. 064. mu. m, 0. 532. mu. m, and 0. 355. mu. m (open access)

Laser-plasma interaction experiments at laser wavelengths of 1. 064. mu. m, 0. 532. mu. m, and 0. 355. mu. m

The effect of laser wavelength on laser-plasma coupling is one of the critical issues facing the laser driven inertial confinement community. The advantages of using lasers with output wavelength less than 1 ..mu..m, such as enhanced absorption and hydrodynamic efficiency, reduction in parametric instabilities and corresponding suprathermal electron generation, have long been predicted theoretically.
Date: January 1, 1982
Creator: Campbell, E. M.; Mead, W. C. & Turner, R. E.
Object Type: Article
System: The UNT Digital Library
Growth regulation by macrophages (open access)

Growth regulation by macrophages

The evidence reviewed here indicates that macrophages, either acting alone or in concert with other cells, influence the proliferation of multiple types of cells. Most of the data indicate that these effects are mediated by soluble macrophage-elaborated products (probably proteins) although the role of direct cell-to-cell contacts cannot be ruled out in all cases. A degree of success has been achieved on the biochemical characterization of these factors, due mainly to their low specific activity in conditioned medium and the lack of rapid, specific assays. Understanding the growth-regulating potential of macrophages is an important and needed area of research.
Date: January 1, 1982
Creator: Wharton, W.; Walker, E. & Stewart, C.C.
Object Type: Article
System: The UNT Digital Library
Diskless LSI-11 systems (open access)

Diskless LSI-11 systems

Programs for dedicated LSI-11 based systems can easily be stored in ROM instead of floppy disks, yet execute the same as disk-stored programs. Two sample systems are described.
Date: January 1, 1982
Creator: Ford, W. & Shirk, D. G.
Object Type: Article
System: The UNT Digital Library
Statistical magnetohydrodynamics and reversed-field-pinch quiescence (open access)

Statistical magnetohydrodynamics and reversed-field-pinch quiescence

A statistical model of a bounded, incompressible, cylindrical magnetofluid is presented. This model predicts the presence of magnetic fluctuations about a cylindrically-symmetric, Bessel-function-model, mean magnetic field, which satisfies del x <B> = ..mu.. <B>. As theta ..-->.. 1.56, the model predicts that the significant region of the fluctuation spectrum narrows down to a single (coherent) m = 1 mode. An analogy between the Debye length of an electrostatic plasma and ..mu../sup -1/ suggests the physical validity o the model's prediction of <deltaB(r)deltaB(r')> when /r - r'/ greater than or equal to ..mu../sup -1/.
Date: January 1, 1982
Creator: Turner, L.
Object Type: Article
System: The UNT Digital Library
Energy-Exchange Project (open access)

Energy-Exchange Project

The purpose of the study was to determine what energy savings can be achieved by coordinating the resources and requirements of two facilities, the 26th Ward Water Pollution Control Plant (WPCP) and a housing development named Starrett City with its own total energy system. It was determined that three energy exchange options were economically and technically feasible. These include: the transfer of digester gas produced at the 26th Ward to the boilers at the Starrett City's total energy plant (TEP); the transfer of hot water heated at the TEP to the 26th Ward for space and process heating; and the transfer of coal effluent waste water from the 26th Ward to the condenser cooling systems at the TEP. Technical information is presented to support the findings. The report addresses those tasks of the statement of work dedicated to data acquisition, analysis, and energy conservation strategies internal to the Starrett City TEP and the community it supplies as well as to the 26th Ward WPCP. (MCW)
Date: April 1, 1982
Creator: unknown
Object Type: Report
System: The UNT Digital Library
NRC plan for cleanup operations at Three Mile Island Unit 2 (open access)

NRC plan for cleanup operations at Three Mile Island Unit 2

This NRC Plan, which defines NRC&#x27;s functional role in cleanup operations at Three Mile Island Unit 2 and outlines NRC&#x27;s regulatory responsibilities in fulfilling this role, is the first revision to the initial plan issued in July 1980 (NUREG-0698). Since 1980, a number of policy developments have occurred which will have an impact on the course of cleanup operations. This revision reflects these developments in the area of NRC&#x27;s review and approval process with regard to cleanup operations as well as NRC&#x27;s interface with the Department of Energy&#x27;s involvement in the cleanup and waste disposal. This revision is also intended to update the cleanup schedule by presenting the cleanup progress that has taken place and NRC&#x27;s role in ongoing and future cleanup activities.
Date: February 1, 1982
Creator: Lo, R. & Snyder, B.
Object Type: Report
System: The UNT Digital Library
Development of 400- to 450-MHz RFQ resonator-cavity mechanical designs (open access)

Development of 400- to 450-MHz RFQ resonator-cavity mechanical designs

In the development of the radio-frequency quadrupole (RFQ) linac, the resonator cavity's mechanical design may be a challenge similar in magnitude to that of the development of the accelerator structure itself. Experience with the all-copper 425-MHz RFQ proof-of-principle linac has demonstrated that the resonator cavity must be structurally stiff and easily tunable. This experience has led to development of copper-plated steel structures having vanes that may be moved within a cylinder for tuning. Design of a flexible vane-to-cylinder radio-frequency (rf) joint, the vane, and the cylinder has many constraints dictated by the small-diameter cavities in the 400-MHz-frequency region. Two types of flexible, mechanical vane-to-cylinder rf joints are being developed at Los Alamos: the C-seal and the rf clamp-joint.
Date: January 1, 1982
Creator: Hansborough, L.D.
Object Type: Report
System: The UNT Digital Library
Nuclear power in the Soviet Bloc (open access)

Nuclear power in the Soviet Bloc

The growth of Soviet Bloc nuclear power generation to the end of the century is evaluated on the basis of policy statements of objectives, past and current nuclear power plant construction, and trends in the potential for future construction. Central to this study is a detailed examination of individual reactor construction and site development that provides specific performance data not given elsewhere. A major commitment to nuclear power is abundantly clear and an expansion of ten times in nuclear electric generation is estimated between 1980 and 2000. This rate of growth is likely to have significant impact upon the total energy economy of the Soviet Bloc including lessening demands for use of coal, oil, and gas for electricity generation.
Date: March 1, 1982
Creator: Davey, W.G.
Object Type: Report
System: The UNT Digital Library
SPXCPL: two-dimensional modeling program of self-potential effects from cross-coupled fluid and heat flow (User's Guide and documentation for Version 1. 0) (open access)

SPXCPL: two-dimensional modeling program of self-potential effects from cross-coupled fluid and heat flow (User's Guide and documentation for Version 1. 0)

The program is applicable to the calculation of self-potential effects due to fluid flow (electrokinetic effects) and heat flow (thermoelectric effects). The geological structure is two dimensional but the sources can be either finite line sources or point sources. The accuracy of the calculated potentials depends on the model discretization and the distance from the source(s). For the default mesh, the accuracy is usually a few percent at a distance of about one unit from the source. Surface boundary conditions for the primary problem require careful consideration as the form of the flow near the air-earth interface can have a profound effect on the resultant electric potentials. For temperature problems the appropriate boundary condition is a constant temperature, which is taken as zero. With this boundary condition there is a normal flux of heat at the surface and there will be induced electrical sources here, if the surface medium has a nonzero coupling coefficient. In the models, zero temperature at the surface is produced by giving the air a very large thermal conductivity.
Date: March 1, 1982
Creator: Sill, W. R. & Killpack, T. J.
Object Type: Report
System: The UNT Digital Library
Use of principal components analysis and three-dimensional atmospheric-transport models for reactor-consequence evaluation (open access)

Use of principal components analysis and three-dimensional atmospheric-transport models for reactor-consequence evaluation

This work explores the use of principal components analysis coupled to three-dimensional atmospheric transport and dispersion models for evaluating the environmental consequences of reactor accidents. This permits the inclusion of meteorological data from multiple sites and the effects of topography in the consequence evaluation; features not normally included in such analyses. The technique identifies prevailing regional wind patterns and their frequencies for use in the transport and dispersion calculations. Analysis of a hypothetical accident scenario involving a release of radioactivity from a reactor situated in a river valley indicated the technique is quite useful whenever recurring wind patterns exist, as is often the case in complex terrain situations. Considerable differences were revealed in a comparison with results obtained from a more conventional Gaussian plume model using only the reactor site meteorology and no topographic effects.
Date: January 1, 1982
Creator: Gudiksen, P. H.; Walton, J. J.; Alpert, D. J. & Johnson, J. D.
Object Type: Article
System: The UNT Digital Library
Extracted current densities from surface conversion sources of negative ions (open access)

Extracted current densities from surface conversion sources of negative ions

The condition for extracting a maximum negative ion current density is found when the product of the radius of the negative ion conversion electrode, the cross-section for negative and positive ion recombination, and the density of positive ions in the ion source equals one. The optimum output is obtained at the highest positive ion density and the smallest electrode radius.
Date: February 10, 1982
Creator: Fink, J.H.
Object Type: Report
System: The UNT Digital Library
Selective population of high-j states via heavy-ion-induced transfer reactions (open access)

Selective population of high-j states via heavy-ion-induced transfer reactions

One of the early hopes of heavy-ion-induced transfer reactions was to populate states not seen easily or at all by other means. To date, however, I believe it is fair to say that spectroscopic studies of previously unknown states have had, at best, limited success. Despite the early demonstration of selectivity with cluster transfer to high-lying states in light nuclei, the study of heavy-ion-induced transfer reactions has emphasized the reaction mechanism. The value of using two of these reactions for spectroscopy of high spin states is demonstrated: /sup 143/Nd(/sup 16/O,/sup 15/O) /sup 144/Nd and /sup 170/Er(/sup 16/O,/sup 15/O..gamma..) /sup 171/Er. (WHK)
Date: January 1, 1982
Creator: Bond, P.D.
Object Type: Article
System: The UNT Digital Library
SIMMER as a safety analysis tool (open access)

SIMMER as a safety analysis tool

SIMMER has been used for numerous applications in fast reactor safety, encompassing both accident and experiment analysis. Recent analyses of transition-phase behavior in potential core disruptive accidents have integrated SIMMER testing with the accident analysis. Results of both the accident analysis and the verification effort are presented as a comprehensive safety analysis program.
Date: January 1, 1982
Creator: Smith, L. L.; Bell, C. R.; Bohl, W. R.; Bott, T. F.; Dearing, J. F. & Luck, L. B.
Object Type: Article
System: The UNT Digital Library
Cause of pitting in beryllium (open access)

Cause of pitting in beryllium

Light microscopy, bare-film radiography, secondary ion mass spectroscopy, electron microprobe and physical testing were used to examine beryllium specimens exhibiting a stratified, pitted, pattern after chemical milling. The objective was to find the cause of this pattern. Specimens were found to have voids in excess of density specification allowances. These voids are attributed, at least in part, to the sublimation of beryllium fluoride during the vacuum hot pressing operation. The origin of the pattern is attributed to these voids and etching out of fines and associated impurities. Hot isostatic pressing with a subsequent heat treatment close residual porosity and dispersed impurities enough to correct the problem.
Date: April 16, 1982
Creator: Kershaw, R. P.
Object Type: Article
System: The UNT Digital Library
Irradiation experiment for lithium ceramics (open access)

Irradiation experiment for lithium ceramics

Solid breeder materials are required in D-T fusion reactor blankets to convert fusion neutrons to tritium and thermal energy while providing some neutron shielding for the magnets. Lithium compounds such as Li/sub 2/O, LiAlO/sub 2/, Li/sub 4/SiO/sub 4/ and Li/sub 2/ZrO/sub 3/ have been proposed as solid breeder materials. Tritium is necessary to maintain the fuel supply for the D-T fusion reaction. No high burnup irradiation performance data is available for these materials in a neutron environment prototypic of the fusion blanket. The FUBR Experiment in EBR-II has been designed and built to evaluate the irradiation performance of these materials.
Date: March 1, 1982
Creator: Hollenberg, G.W.
Object Type: Article
System: The UNT Digital Library
Institutional and Financial Guide to Geothermal District Heating. Serial No. 2 (open access)

Institutional and Financial Guide to Geothermal District Heating. Serial No. 2

General planning considerations which affect nearly every community are reviewed, and alternative operating structures which are available to communities are reviewed, including local governments, nonprofit cooperatives, private enterprises, and joint ventures. The financing options available to publicly-owned and privately-owned district heating systems are then summarized. The geothermal production and distribution activities most appropriate to each type of operating structure are reviewed, along with typical equity and debt funding sources. The tax advantages for private developers are described, as are the issures of customer contracts and service prices, and customer retrofit financing. The treatment is limited to an introductory overview. (LEW)
Date: March 1, 1982
Creator: unknown
Object Type: Report
System: The UNT Digital Library