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Recovery of deformed and hydrogen-charge palladium

Description: 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 obt… more
Date: January 1, 1982
Creator: Snead, C. L. Jr.; Lynn, K. G. & Lynch, J. F.
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Partner: UNT Libraries Government Documents Department
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Excitation of giant resonances via direct reactions

Description: 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 … more
Date: January 1, 1982
Creator: Bertrand, F.E.
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Partner: UNT Libraries Government Documents Department
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Picotron 100 streak tubes as a 150-channel photometer

Description: 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 lack… more
Date: January 1, 1982
Creator: Majumdar, S.; Weiss, P.B. & Black, J.P.
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Partner: UNT Libraries Government Documents Department
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Laser-plasma interaction experiments at laser wavelengths of 1. 064. mu. m, 0. 532. mu. m, and 0. 355. mu. m

Description: 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.
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Partner: UNT Libraries Government Documents Department
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Growth regulation by macrophages

Description: 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 activit… more
Date: January 1, 1982
Creator: Wharton, W.; Walker, E. & Stewart, C.C.
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Partner: UNT Libraries Government Documents Department
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Diskless LSI-11 systems

Description: 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.
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Partner: UNT Libraries Government Documents Department
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Statistical magnetohydrodynamics and reversed-field-pinch quiescence

Description: 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/ suggest… more
Date: January 1, 1982
Creator: Turner, L.
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Partner: UNT Libraries Government Documents Department
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Development of 400- to 450-MHz RFQ resonator-cavity mechanical designs

Description: 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 tuni… more
Date: January 1, 1982
Creator: Hansborough, L.D.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Use of principal components analysis and three-dimensional atmospheric-transport models for reactor-consequence evaluation

Description: 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 dispersi… more
Date: January 1, 1982
Creator: Gudiksen, P. H.; Walton, J. J.; Alpert, D. J. & Johnson, J. D.
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Partner: UNT Libraries Government Documents Department
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Selective population of high-j states via heavy-ion-induced transfer reactions

Description: 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 react… more
Date: January 1, 1982
Creator: Bond, P.D.
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Partner: UNT Libraries Government Documents Department
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SIMMER as a safety analysis tool

Description: 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.
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Partner: UNT Libraries Government Documents Department
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Evidence of former higher temperatures from alteration minerals, Bostic 1-A well, Mountain Home, Idaho

Description: Cuttings from the silicic volcanics in the Bostic 1-A well near Mountain Home, Idaho have been examined petrographically with the assistance of x-ray diffraction and electron microprobe analyses. Results indicate that these rocks have been subjected to much higher temperatures than were observed in the well in 1974, when a static temperature log was run. It is not known to what extent the alternation may be due to greater depth of burial in the past, or whether it resulted from an early hydroth… more
Date: January 1, 1982
Creator: Arney, B.
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Partner: UNT Libraries Government Documents Department
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Calculations of thermal-reactor spent-fuel nuclide inventories and comparisons with measurements

Description: Comparisons with integral measurements have demonstrated the accuracy of CINDER codes and libraries in calculating aggregate fission-product properties, including neutron absorption, decay power, and decay spectra. CINDER calculations have, alternatively, been used to supplement measured integral data describing fission-product decay power and decay spectra. Because of the incorporation of the extensive actinide library and the use of ENDF/B-V data, it is desirable to compare the inventory of i… more
Date: January 1, 1982
Creator: Wilson, W. B.; LaBauve, R. J. & England, T. R.
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Partner: UNT Libraries Government Documents Department
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Acoustic agglomeration of power plant fly ash. Final report

Description: The work has shown that acoustic agglomeration at practical acoustic intensities and frequencies is technically and most likely economically viable. The following studies were performed with the listed results: The physics of acoustic agglomeration is complex particularly at the needed high acoustic intensities in the range of 150 to 160 dB and frequencies in the 2500 Hz range. The analytical model which we developed, although not including nonlinear acoustic efforts, agreed with the trends obs… more
Date: January 1, 1982
Creator: Reethof, G. & McDaniel, O.H.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Aspects of model selection in multivariate analyses

Description: Analysis of data sets that involve large numbers of variables usually entails some type of model fitting and data reduction. In regression problems, a fitted model that is obtained by a selection process can be difficult to evaluate because of optimism induced by the choice mechanism. Problems in areas such as discriminant analysis, calibration, and the like often lead to similar difficulties. The preceeding sections reviewed some of the general ideas behind assessment of regression-type predic… more
Date: January 1, 1982
Creator: Picard, R.
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Partner: UNT Libraries Government Documents Department
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Interaction of noble-metal fission products with pyrolytic silicon carbide

Description: Fuel particles for the High-Temperature Gas-Cooled Reactor (HTGR) contain layers of pyrolytic carbon and silicon carbide, which act as a miniature pressure vessel and form the primary fission product barrier. Of the many fission products formed during irradiation, the noble metals are of particular interest because they interact significantly with the SiC layer and their concentrations are somewhat higher in the low-enriched uranium fuels currently under consideration. To study fission product-… more
Date: January 1, 1982
Creator: Lauf, R. J. & Braski, D. N.
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Partner: UNT Libraries Government Documents Department
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Internal magnetic fields in hcp-iron

Description: The magnetic behavior of hcp-Fe (epsilon iron) has been investigated by the Moessbauer Effect over a wide range of temperature T, pressure P, and applied magnetic field H/sub 0/. The internal field H/sub i/ of the induced moment is given by H/sub i/ = 0.20 +- .01 H/sub 0/ and is independent of T and P. Enhanced paramagnetism is suggested as the most likely origin for a contribution of this magnitude to H/sub i/.
Date: January 1, 1982
Creator: Taylor, R. D.; Cort, G. & Willis, J. O.
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Partner: UNT Libraries Government Documents Department
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Integrity of PWR pressure vessels during overcooling accidents

Description: The reactor pressure vessel in a pressurized water reactor is normally subjected to temperatures and pressures that preclude propagation of sharp, crack-like defects that might exist in the wall of the vessel. However, there is a class of postulated accidents, referred to as overcooling accidents, that can subject the pressure vessel to severe thermal shock while the pressure is substantial. As a result of such accidents vessels containing high concentrations of copper and nickel, which enhance… more
Date: January 1, 1982
Creator: Cheverton, R.D.; Iskander, S.K. & Whitman, G.D.
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Partner: UNT Libraries Government Documents Department
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Light composite fermions: an overview

Description: Some rules which have been proposed, including 't Hooft's anomaly conditions, decoupling conditions and tumbling versus no tumbling are discussed. Then mass generation mechanisms for composite fermions are covered, including weak gauging, strong gauging, and unification. The origin of the different generations of quarks and leptons is then considered. In the context of composite models, the three generations of quarks and leptons must appear in the first approximation as three sets of massless … more
Date: January 1, 1982
Creator: Raby, S.
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Partner: UNT Libraries Government Documents Department
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Clonal theory of radiation carcinogenesis

Description: In some cases, usually involving high-LET radiations, the dose response at low doses follows a power function of dose with exponent less than one over a wide dose range. This type of response is of great interest since (a) it implies greater effect per unit dose at progressively smaller doses, and (b) it is not predicted by most models and theories of radiobiology. A theoretical framework is presented for responses having the above characteristics over a dose range extending over a factor of 10… more
Date: January 1, 1982
Creator: Baum, J.W.
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Partner: UNT Libraries Government Documents Department
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Microfaunal evidence of age and depositional environments of the Cerro Prieto section (Plio-Pleistocene), Baja California, Mexico

Description: Microfossils including benthic and planktic foraminifera, ostracodes, calcareous algae, fish skeletal material, and fragments of pelecypods were found in 14 core samples from depths of 185 to 1952 m in the Cerro Prieto geothermal field, providing evidence of both the age and depositional history of sediments comprising the 3000-m-thick Pliocene and Pleistocene section in this area. Ostracodes of brackish water and marine origin constitute the most common microfossils present in this sequence oc… more
Date: January 1, 1982
Creator: Ingle, J.C. Jr.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Electron bremsstrahlung angular-distribution fits for atomic numbers 1 less than or equal to Z less than or equal to 92, and incident-electron energies 1 keV less than or equal to T less than or equal to 500 keV

Description: The analytic fit of a simple expression to the electron bremsstrahlung angular distribution cross section d/sup 2/sigma/dkd..cap omega.. (differential in the emitted photon energy k and angle ..cap omega..) is investigated. Optimal choices for the fit parameters are determined and fit coefficients are tabulated for a large number of neutral-atom cases. Results are also presented for fits to the relativistic Coulomb-Born approximation. Comparisons between the screened neutral-atom results and th… more
Date: January 1, 1982
Creator: Kissel, L.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Shielding considerations for advanced space nuclear reactor systems

Description: To meet the anticipated future space power needs, the Los Alamos National Laboratory is developing components for a compact, 100 kW/sub e/-class heat pipe nuclear reactor. The reactor uses uranium dioxide (UO/sub 2/) as its fuel, and is designed to operate around 1500 k. Heat pipes are used to remove thermal energy from the core without the use of pumps or compressors. The reactor heat pipes transfer mal energy to thermoelectric conversion elements that are advanced versions of the converters u… more
Date: January 1, 1982
Creator: Angelo, J.P. Jr. & Buden, D.
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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.
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Partner: UNT Libraries Government Documents Department
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