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Electro-optical streak camera system for use at 1. 3. mu. m

Description: An electro-optical streak camera for use at 1.3 ..mu..m is described, including determination of the streak tube absolute photocathode sensitivity and system dynamic range. Nonlinear response at higher input intensities suggests multi-photon photocathode absorption.
Date: January 1, 1979
Creator: Palmer, M.A. & Palmer, R.E.
Partner: UNT Libraries Government Documents Department

Efficient numerical method for time independent plasticity

Description: A new numerical method for the solution of plasticity equations is presented. The plasticity model is a commonly used elastic-plastic strain hardening model for combined isotropic-kinematic hardening with Ziegler's modification. Thermal strains and temperature variable properties are included. The method is also specialized to the non-thermal linear strain hardening case where only two additional vector and two scalar algebraic equations, including one square root, are needed over that needed for the elastic case. The method has roughly the same accuracy as conventional numerical treatments of the plasticity equations but requires roughly one-third as much computational time.
Date: November 1, 1977
Creator: Krieg, R.D.
Partner: UNT Libraries Government Documents Department

EPR of ion-implanted, laser-annealed silicon

Description: Electron paramagnetic resonance and ion backscattering measurements were made on ion-implanted, pulsed laser-annealed silicon. For phosphorus-implanted silicon (3 x 10/sup 13/ 200 keV P/sup +//cm/sup 2/) the electrical activity of the implanted donors is restored after laser annealing with greater than or equal to 1.8 J/cm/sup 2/. Silicon made amorphous with 2 x 10/sup 15/ 200 keV Si/sup +//cm/sup 2/ and implanted with 3 x 10/sup 13/ 200 keV P/sup +//cm/sup 2/ can be restored to crystallinity after laser annealing, but electrical activity of the P was not restored due to residual defects for laser energies less than or equal to 3 J/cm/sup 2/. Electrical activity can be restored, at least in part, for amorphous silicon implanted at lower energies (approx. = 50 keV). We also observed that N/sub 2/ reacts with amorphous silicon surfaces to form silicon-nitride. Under laser annealing the N is redistributed and exists as an N interstitial within the implanted layer.
Date: January 1, 1979
Creator: Brower, K.L. & Peercy, P.S.
Partner: UNT Libraries Government Documents Department

Evaluation of hand-held ion-mobility explosives vapor detectors

Description: Two types of ion-mobility detectors were evaluated in both laboratory and field tests. Laboratory test results show that these detectors are highly sensitive to dynamite and pistol powder and have good false-alarm agent rejection. Field tests of these two detectors revealed that they would detect dynamite and Ball-C-Propellent in free air. However, neither of the ion-mobility detectors would detect these explosives if the explosives were concealed.
Date: December 1, 1979
Creator: Burrows, T.A. & Thoma, P.J.
Partner: UNT Libraries Government Documents Department

Automated electronic intruder simulator for evaluation of odd frequency microwave detectors

Description: A microwave intruder simulator for testing motion detection sensors is described. This simulator can be used to evaluate a variety of microwave sensors regardless of the value of the center frequency of the signal utilized. Representative curves from the evaluation of one microwave sensor are also presented.
Date: January 1, 1979
Partner: UNT Libraries Government Documents Department

Particle beam fusion. Progress report, April 1978-December 1978

Description: During this period substantial improvements in the theoretical basis for particle beam fusion as well as the execution of critical experiments were instrumental in further definition of the optimum route to our goals of demonstrating scientific and practical feasibility. The major emphasis in the program continues to be focused primarily on issues of power concentration and energy deposition of intense particle beams in solid targets. This utilization of program resources is directed toward conducting significant target implosion and thermonuclear burn experiments using EBFA-I (1 MJ) in the 1981-1983 time period. This step, using EBFA-I, will then set the stage for net energy gain experiments to follow on EBFA-II (> 2 MJ) after 1985. Current program emphasis and activities differ substantially from those stressed in the laser approaches to inertial confinement fusion. Here the critical issues relate to delivering the needed power densities and energies to appropriate targets and to insure that the coupling of energy is efficient and matches target requirements.
Date: December 1, 1979
Partner: UNT Libraries Government Documents Department

Basic data report for drillhole WIPP 25 (Waste Isolation Pilot Plant - WIPP)

Description: WIPP 25 was drilled on the eastern edge of Nash Draw (SW 1/4, Sec. 15, T22S, R30E) in Eddy County, New Mexico, to determine subsurface stratigraphy and examine dissolution features above undisturbed salt in the Salado Formation. Determination of dissolution rates will refine previous estimates and provide short-term (geologically) rates for WIPP risk assessments. The borehole encountered, from top to bottom, Pleistocene sediments (17 ft with fill material for pad), Dewey Lake Red Beds (215 ft, Rustler Formation (333 ft, and 90 ft of the upper Salado Formation. A dissolution residue, 37 ft thick, is at the top of the Salado Formation overlying halite-rich beds. In addition to obtaining nearly continuous core from the surface to total depth (655 ft, geophysical logs were taken to measure acoustic velocities, density, radioactivity, and formation resistivity. An interpretive report on dissolution in Nash Draw will be based on combined borehole basin data, surface mapping, and laboratory analyses of Nash Draw rocks and fluids. The WIPP is to demonstrate (through limited operations) disposal technology for transuranic defense wastes and to then be converted to a repository. The WIPP will also provide research facilities for interactions between high-level waste and salt.
Date: September 1, 1979
Partner: UNT Libraries Government Documents Department

Basic data report for drillhole WIPP 21 (Waste Isolation Pilot Plant - WIPP)

Description: WIPP 21 is an exploratory borehole whose objective is to determine the nature of the near-surface formations after seismic information indicated a possible fault. The borehole is located in section 20, T.22S., R.31E., in eastern Eddy County, New Mexico, and was drilled between May 24 and 26, 1978. The hole was drilled to a depth of 1046 feet and encountered, from top to bottom, surficial Holocene deposits (6', including artificial fill for drill pad), the Mescalero caliche (6'), the Santa Rosa Sandstone (34'), the Dewey Lake Red Beds (487'), the Rustler Formation (308'), and the upper portion of the Salado Formation (178'). Cuttings were collected at 10-foot intervals. A suite of goephysical logs was run to measure acoustic velocities, density, and radioactivity. On the basis of comparison with other geologic sections drilled in the area, the WIPP 21 section is a normal stratigraphic sequence and it does not show structural disruption. The WIPP is to demonstrate (through limited operations) disposal technology for transuranic defense wastes. The WIPP will also provide facilities to research interactions between high-level waste and salt.
Date: March 1, 1980
Partner: UNT Libraries Government Documents Department

Subseabed disposal program annual report, January-December 1978. Volume II. Principal investigator progress reports

Description: The topics covered in this report include: geologic siting considerations for the disposal of radioactive wastes into submarine geologic formations; geologic assessment of the MPG-1 regions Central North Pacific; site mapping; geotechnical aspects of subsurface seabed disposal; heat transfer, thermal and fluid physics in the deep ocean sediments; mechanical response predictive capability; sediment-seawater interaction at 300/sup 0/C, 500 bars; stability of actinides in chloride media; cannister corrosion studies; nuclide sorption and migration; development of apparatus and measurement of thermal conductivity of seabed illite and smectite at temperatures to 500/sup 0/C at simulated depths to 15,000 ft (9000 psi); in-situ heat transfer experiments; preliminary seabed disposal transport modeling studies; radionuclide migration studies; radionuclide distributions in deep ocean cores; benthic biological studies; deep sea microbial studies; activity rates of abyssal communities; Deep-towed RUM III (Sandia Seabed working platform): a third-generation remote underwater manipulator; long coring facility program; transportation; legal, political, and institutional implications of the Seabed Program for radioactive waste disposal.
Date: October 1, 1979
Partner: UNT Libraries Government Documents Department

Development of boron carbide-copper cermets. Status report

Description: The status of a program to develop a B/sub 4/C-Cu cermet for Breeder Reactor spent-fuel shipping cask neutron shields is presented. It is shown that inspectable 6 to 7 cm thick 60 to 70 volume percent B/sub 4/C cermets can be fabricated using hot isostatic powder processing procedures. An alternative manufacturing method, rheocasting, also appears to be a promising, perhaps more cost-effective method for producing these cermets. Recommendations for further development of these manufacturing processes are given.
Date: September 1, 1979
Partner: UNT Libraries Government Documents Department

Dielectric strength of SiO/sub 2/ in a CMOS transistor structure

Description: The distribution of experimental dielectric strengths of SiO/sub 2/ gate dielectric in a CMOS transistor structure is shown to be composed of a primary, statistically-normal distribution of high dielectric strength and a secondary distribution spread through the lower dielectric strength region. The dielectric strength was not significantly affected by high level (1 x 10/sup 6/ RADS (Si)) gamma radiation or high temperature (200/sup 0/C) stress. The primary distribution breakdowns occurred at topographical edges, mainly at the gate/field oxide interface, and the secondary distribution breakdowns occurred at random locations in the central region of the gate.
Date: January 1, 1979
Creator: Soden, J.M.
Partner: UNT Libraries Government Documents Department

CORCON: a computer program for modelling molten fuel/concrete interactions. [PWR; BWR]

Description: A computer program modelling the interaction between molten core materials and structural concrete is being developed to provide a capability for making quantitative estimates of reactor fuel-melt accidents. The principal phenomenological models, inter-component heat transfer, concrete erosion, and melt/gas chemical reactions, are described. A code test comparison calculation is discussed.
Date: January 1, 1980
Creator: Muir, J.F.
Partner: UNT Libraries Government Documents Department

Crashworthy sealed pressure vessel for plutonium transport

Description: A rugged transportation package for the air shipment of radioisotopic materials was recently developed. This package includes a tough, sealed, stainless steel inner containment vessel of 1460 cc capacity. This vessel, intended for a mass load of up to 2 Kg PuO/sub 2/ in various isotopic forms (not to exceed 25 watts thermal activity), has a positive closure design consisting of a recessed, shouldered lid fastened to the vessel body by twelve stainless-steel bolts; sealing is accomplished by a ductile copper gasket in conjunction with knife-edge sealing beads on both the body and lid. Follow-on applications of this seal in newer, smaller packages for international air shipments of plutonium safeguards samples, and in newer, more optimized packages for greater payload and improved efficiency and utility, are briefly presented.
Date: January 1, 1980
Creator: Andersen, J.A.
Partner: UNT Libraries Government Documents Department

Conasauga Near Surface Heater Experiment. Implications for a repository sited in a water-saturated argillaceous formation

Description: Results of the Conasauga Near Surface Heater Experiment suggest that the effects of ground water on a repository located in shale would be most pronounced in their influence on chemical processes. Despite the water-saturated condition of the Conasauga shale, conduction, not convection, was the principal mode of heat transport. Metal corrosion, however, was found to be significantly enhanced by the refluxing steam. The several centimeters of scale left behind by the boiling water, in a repository, could interfere with retrieval operations or form a coating of low thermal conductivity material on a canister. Finally, alternate wetting and drying due to sporadic steam generation caused up to 20 microns of alteration on a sample of borosilicate waste glass simulant (PNL 75-25) included in the test.
Date: January 1, 1979
Creator: Krumhansl, J.L. & Sundberg, W.D.
Partner: UNT Libraries Government Documents Department

Conasauga near-surface heater experiment. Final report

Description: The Conasauga Experiment was undertaken to begin assessment of the thermomechanical and chemical response of a specific shale to the heat resulting from emplacement of high-level nuclear wastes. Canister-size heaters were implanted in Conasauga shale in Tennessee. Instrumentation arrays wee placed at various depths in drill holes around each heater. The heaters operated for 8 months and, after the first 4 days, were maintained at 385/sup 0/C. Emphasis was on characterizing the thermal and mechanical response of the formation. Conduction was the major mode of heat transport; convection was perceptible only at temperatures above the boiling point of water. Despite dehydration of the shale at higher temperatures, in situ thermal conductivity was essentially constant and not a function of temperature. The mechanical response of the formation was a slight overall expansion, apparently resulting in a general decrease in permeability. Metallurgical observations were made, the stability of a borosilicate glass wasteform simulant was assessed, and changes in formation mineralogy and groundwater composition were documented. In each of these areas, transient nonequilibrium processes occur that affect material stability and may be important in determining the integrity of a repository. In general, data from the test reflect favorably on the use of shale as a disposal medium for nuclear waste.
Date: November 1, 1979
Creator: Krumhansl, J.L.
Partner: UNT Libraries Government Documents Department

Controlling magnetic field profiles

Description: A method for designing solenoid magnets with controlled field profiles is discussed. The method, originated by D.B. Montgomery, minimizes both the field errors and the power consumption. An NOS time-sharing computer program for the CDC-6600, entitled MAGCOR, was constructed to provide an interactive magnet design capability. Results obtained during the design of magnets for a radial line electron accelerator are presented. 9 figures.
Date: April 1, 1979
Creator: Freeman, J.R.
Partner: UNT Libraries Government Documents Department

Coal liquefaction process research quarterly report, October-December 1979

Description: This quarterly report summarizes the activities of Sandia's continuing program in coal liquefaction process research. The overall objectives are to: (1) provide a fundamental understanding of the chemistry of coal liquefaction; (2) determine the role of catalysts in coal liquefaction; and (3) determine the mechanism(s) of catalyst deactivation. The program is composed of three major projects: short-contact-time coal liquefaction, mineral effects, and catalyst studies. These projects are interdependent and overlap significantly.
Date: March 1, 1980
Creator: Bickel, T.C.; Curlee, R.M.; Granoff, B.; Stohl, F.V. & Thomas, M.G.
Partner: UNT Libraries Government Documents Department

Cross sections for electron and photon processes required by electron-transport calculations

Description: Electron-transport calculations rely on a large collection of electron-atom and photon-atom cross-section data to represent the response characteristics of the target medium. These basic atomic-physics quantities, and certain qualities derived from them that are now commonly in use, are critically reviewed. Publications appearing after 1978 are not given consideration. Processes involving electron or photon energies less than 1 keV are ignored, while an attempt is made to exhaustively cover the remaining independent parameters and target possibilities. Cases for which data improvements can be made from existing information are identified. Ranges of parameters for which state-of-the-art data are not available are sought out, and recommendations for explicit measurements and/or calculations with presently available tools are presented. An attempt is made to identify the maturity of the atomic-physics data and to predict the possibilities for rapid changes in the quality of the data. Finally, weaknesses in the state-of-the-art atomic-physics data and in the conceptual usage of these data in the context of electron-transport theory are discussed. Brief attempts are made to weight the various aspects of these questions and to suggest possible remedies.
Date: November 1, 1979
Creator: Peek, J.M.
Partner: UNT Libraries Government Documents Department

Calorimetric measurement of electron energy deposition in extended media. Theory vs experiment

Description: A new calorimetric technique has been developed for measuring electron energy deposition profiles in one dimension. The experimental procedures and theoretical analyses required in the application of the new method are reviewed. Extensive results are presented for electron energy deposition profiles in semi-infinite homogeneous and multilayer configurations. These data cover a range of elements from beryllium through uranium at source energies from 0.3 to 1.0 MeV (selected data at 0.5 and 0.1 MeV) and at incident angles from 0/sup 0/ to 60/sup 0/. In every case, the experimental profiles are compared with the predictions of a coupled electron/photon Monte Carlo transport code. Overall agreement between theory and experiment is very good. However, there appears to be a tendency for the theoretical profiles to be higher near the peaks and lower near the tails, especially in high-Z materials. There is also a discrepancy between theory and experiment in low-Z materials near high-Z/low-Z interfaces.
Date: January 1, 1980
Creator: Lockwood, G.J.; Ruggles, L.E.; Miller, G.H. & Halbleib, J.A.
Partner: UNT Libraries Government Documents Department

Calibration model for the DCXC x-ray camera

Description: A physical model for the DCXC camera used in x-radiographic studies of inertial confinement fusion (ICF) targets is described. Empirical calibration procedures, based on pulsed, bremsstrahlung sources, are proposed.
Date: January 1, 1980
Creator: Fehl, D.L. & Chang, J.
Partner: UNT Libraries Government Documents Department

Characterization of hydrogen species on metal-oxide surfaces by electron-stimulated desorption: TiO/sub 2/ and SrTiO/sub 3/*

Description: The hydrogen species on TiO/sub 2/ and SrTiO/sub 3/ have been characterized using the site specificity of electron-excited Auger Stimulated Desorption (ASD). Hydrogen is found to be bonded to surface Ti's in hydride-type bonds, to subsurface or bridgebonded O's in a hydroxyl-like bond, or be part of a surface hydroxyl. On SrTiO/sub 3/ the Ti-H and surface OH species are also found plus a high density of Sr-H and very little Sr-OH bonding. The general features of ASD, both electron- and photon-excited, are discussed.
Date: January 1, 1979
Creator: Knotek, M.L.
Partner: UNT Libraries Government Documents Department

Characterization and properties of plasma polymerized 2-vinylpyridine

Description: The chemical structure, aging, thermal, and adhesive behavior of plasma-deposited 2-vinylpyridine has been investigated. The molecular structure of the plasma polymer is significantly different from the conventional, linear polymer and is strongly dependent on plasma reactor variables. Additional cyano, methyl, and olefinic groups were identified in the plasma polymer, and aromaticity retention was reduced at the more severe (low pressure, high rf power) reactor conditions studied. Post-deposition oxidation occurred, which followed approximately first order kinetics initially (..delta..E approx. 11.6 Kcal/mole, with approx. 25% conversion of aromatic rings to an aromatic ketone in 4.5 months at 23/sup 0/C). Oxidation was significantly reduced in vacuum, inert gas, and hydrogen atmospheres. Thermal weight loss began at relatively low temperatures and appeared to accompany an exothermic, irreversible cross-linking reaction which began at about 100/sup 0/C. Principle low temperature decomposition products were low molecular weight gases (primarily, CO/sub 2/) and 2-methylpyridine. A quantitative tensile-pull adhesion test was developed. Using this technique, the plasma polymer-aluminum cohesive bond strength was found to be 480 psi and was degraded at high humidity levels.
Date: November 1, 1979
Creator: Bieg, K.W.; Ottesen, D.K. & Brower, K.L.
Partner: UNT Libraries Government Documents Department

Active neutron technique for detecting attempted special nuclear material diversion

Description: The identification of special nuclear material (SNM) diversion is necessary if SNM inventory control is to be maintained at nuclear facilities. (Special nuclear materials are defined for this purpose as either /sup 235/U of /sup 239/Pu.) Direct SNM identification by the detection of natural decay or fission radiation is inadequate if the SNM is concealed by appropriate shielding. The active neutron interrogation technique described combines direct SNM identification by delayed fission neutron (DFN) detection with implied SNM detection by the identification of materials capable of shielding SNM from direct detection. This technique is being developed for application in an unattended material/equipment portal through which items such as electronic instruments, packages, tool boxes, etc., will pass. The volume of this portal will be 41-cm wide, 53-cm high and 76-cm deep. The objective of this technique is to identify an attempted diversion of at least 20 grams of SNM with a measurement time of 30 seconds.
Date: January 1, 1979
Creator: Smith, G.W. & Rice, L.G. III
Partner: UNT Libraries Government Documents Department

Assessment of positron annihilation as a potential non-destructive examination technique

Description: The positron annihilation technique can provide a sensitive measure of defect density in metals. In this program the technique has been used to monitor defects generated during plastic deformation by cold work or fatigue cycling. The primary goals have been: (1) to assess the degree of sensitivity of the technique; (2) to correlate positron annihilation readings with observed microstructural changes to better understand the physical basis for these readings; and (3) to determine correlations between positron annihilation measurements and number of fatigue cycles. Examination of fatigued samples by transmission electron microscopy indicates some correlation between dislocation density and positron annihilation lineshape parameter (determined by the Doppler broadening technique). However, annealing studies of deformed samples indicate that positron annihilation response in 316 stainless steel is sensitive primarily to excess vacancies generated during the deformation and is less sensitive to dislocation density. Data on deformed nickel show sensitivity to both vacancies and dislocations. In general, lineshape parameter values tend to achieve a constant level at approximately 10% of fatigue life.
Date: January 1, 1979
Creator: Jones, W.B.; Van Den Avyle, J.A.; Gauster, W.B. & Wampler, W.R.
Partner: UNT Libraries Government Documents Department