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11,813 Matching Results
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Elastic p-/sup 4/He scattering near 1 GeV
New 1.029 GeV p-/sup 4/He data from an Argonne-UCLA-Minnesota collaboration are in excellent agreement with existing multiple diffraction theory predictions. The theoretical calculation includes spin and isospin dependence of the ..delta.. intermediate state process that fills the first diffraction minimum. The recently normalized Saclay data and the older Brookhaven data disagree with our calculation and the new data.
Date:
February 1, 1977
Creator:
Wallace, S. J. & Alexander, Y.
System:
The UNT Digital Library
Directional growth of pearlite in iron--carbon eutectoid alloys. [Rate]
Pearlite was transformed directionally by passing a zone of austenite through high purity Fe--C alloy bars of eutectoid composition. Using a small embedded thermocouple, the temperature gradient at both the austenitizing edge and the pearlite transformation edge of the austenitic zone was recorded. A sharp change in gradient occurred due to the change in thermal conductivity between the phases at each interface. The point of change in gradient enabled the temperature of both interfaces to be determined as a function of velocity. It was found that the undercooling of the pearlite transformation interface below the eutectoid temperature was quadratically dependent on the velocity of transformation. No superheating at the austenitizing interface was observed. Interlamellar spacing measurements of pearlite showed an inverse quadratic dependence of spacing on velocity. These two results are compared with theory. Volume diffusion of carbon through austenite adequately describes the kinetics of the decomposition of austenite to pearlite although extrapolated carbon diffusivities from high temperature austenite data are a factor of 2 to 4 too small. The interlamellar spacing of pearlite and the pearlite transformation interface temperature as a function of velocity are compared to other constant velocity transformation studies as well as isothermal investigations. Results of …
Date:
February 1, 1977
Creator:
Pearson, D. D.
System:
The UNT Digital Library
Methods for the isolation and identification of polycyclic aromatic hydrocarbons found in complex mixtures and the determination of their possible toxicity by means of a host mediated bioassay technique. Progress report, July 1, 1976--February 1, 1977. [Cultured mouse leumemia cell bioassay system]
Techniques were developed to produce excellent high performance glass capillary columns for gas chromatographic analyses of a wide range of complex mixtures of organic compounds, including those containing a wide array of polycyclic aromatic hydrocarbons (PAH) derived from a coal liquefaction process. Work was begun to assess the potential mutogenicity and/or carcinogenicity of the various isolated PAH fractions utilizing a unique host mediated bioassay system. Preliminary results indicate that further efforts will be required to determine dose response parameters of cultured mouse leukemia cells, as well as suitable vehicles for the satisfactory introduction of certain PAH fractions into this particular bioassay system.
Date:
February 1, 1977
Creator:
Lipsky, S. R.; Alexander, G.; McMurray, W. & Capizzi, R.
System:
The UNT Digital Library
Ultraprecise parabolic interpolator for numerically controlled machine tools. [Digital differential analyzer circuit]
The mathematical basis for an ultraprecise digital differential analyzer circuit for use as a parabolic interpolator on numerically controlled machines has been established, and scaling and other error-reduction techniques have been developed. An exact computer model is included, along with typical results showing tracking to within an accuracy of one part per million.
Date:
February 1, 1977
Creator:
Davenport, C. M.
System:
The UNT Digital Library
Some alternatives to the mixed oxide fuel cycle
While on initial examination each of the six fuel cycle concepts (tandem cycle, extended burnup, fuel rejuvenation, coprocessing, partial reprocessing, and thorium) described in the report may have some potential for improving safeguards, none of the six appears to have any other major or compelling advantages over the mixed oxide (MOX) fuel cycle. Compared to the MOX cycle, all but coprocessing appear to have major disadvantages, including severe cost penalties. Three of the concepts-tandem, extended burnup, and rejuvenation--share the basic problems of the throwaway cycle (GESMO Alternative 6): without reprocessing, high-level waste volumes and costs are substantially increased, and overall uranium utilization decreases for three reasons. First, the parasitic fission products left in the fuel absorb neutrons in later irradiation steps reducing the overall neutronic efficiencies of these cycles. Second, discarded fuel still has sufficient fissile values to warrant recycle. Third, perhaps most important, the plutonium needed for breeder start-up will not be available; without the breeder, uranium utilization would drop by about a factor of sixty. Two of the concepts--coprocessing and partial reprocessing--involve variations of the basic MOX fuel cycle's chemical reprocessing step to make plutonium diversion potentially more difficult. These concepts could be used with the MOX fuel …
Date:
February 1, 1977
Creator:
Deonigi, D. E.; Eschbach, E. A.; Goldsmith, S.; Pankaskie, P. J.; Rohrmann, C. A. & Widrig, R. D.
System:
The UNT Digital Library
Influence of strain rate and temperature on the yield and fracture toughness behavior of selected steels for an LMFBR spent fuel shipping cask, a literature assessment
The literature has been reviewed to determine the possible influences of strain rate and temperature on the yield and fracture toughness behavior of selected steels suggested for use in an LMFBR Spent Fuel Shipping Cask. Based on this information, recommendations have been made for further work which is intended to alleviate potential problems prior to their having a major impact on the shipping cask program.
Date:
February 1, 1976
Creator:
Rack, H. J.
System:
The UNT Digital Library
Collisional effects on trapped electron instabilities
The effects of collisions on dissipative trapped electron instabilities are evaluated by distinguishing between the perpendicular and parallel electron velocity components when calculating trapped and untrapped electron contributions. The growth rate is obtained for all regimes of collisionality and reduces to previous results in appropriate limits. We show that the dominant effect of finite collisionality is to determine the number of trapped and untrapped electrons and that collisional broadening removes the resonant electron response only for collision frequencies greater than or equal to ten times the wave frequency, ..nu../sub e/ greater than or equal to 10 ..omega... For such large ..nu../sub e//..omega.., ion-ion collisions are found to exert a far stronger stabilizing influence than broadening.
Date:
February 1, 1977
Creator:
Tsang, K. T.; Callen, J. D. & Catto, P. J.
System:
The UNT Digital Library
Light Water Reactor Fuel Recycle program plutonium nitrate-to-oxide conversion project progress report, July--September 1976
None
Date:
February 7, 1977
Creator:
Lehmkuhl, G. D.
System:
The UNT Digital Library
Irradiation performance of HTGR fertile fuel in HFIR target capsules HT-12 through HT-15. Part I. Experiment description and fission product behavior
Sixteen types of Biso-coated designs, on ThO/sub 2/ kernels, were irradiated in High Flux Isotope Reactor target capsules HT-12 through HT-15. The report addresses the description of the experiment and extensive postirradiation analyses and experiments to determine fertile-particle burnup, fuel coating failures, and fission product behavior. Several low-temperature isotropic (LTI) pyrocarbon coatings, which ''survived'' according to visual inspection, were shown to have developed permeability during irradiation. These particles were irradiated at temperatures approximately equal to 1250/sup 0/C and to burnups equal to or greater than 8 percent fission per initial heavy-metal atom (FIMA). No evidence of permeability was found in similar particles irradiated at temperatures approximately equal to 1550/sup 0/C and burnups approximately equal to 16 percent FIMA. Failures due to permeability were not detectable by visual inspection but required a more extensive investigation by the 1000/sup 0/C gaseous chlorine leaching technique. Maximum particle surface operating temperatures were found to be approximately 300/sup 0/C in excess of design limits of 900/sup 0/C (low-temperature magazines) and 1250/sup 0/C (high-temperature magazines). The extremes of high temperatures and fast neutron fluences up to 1.6 x 10/sup 22/ neutrons/cm/sup 2/ produced severe degradation and swelling of the Poco graphite magazines and sample holders.
Date:
February 1, 1977
Creator:
Kania, M. J.; Lindemer, T. B.; Morgan, M. T. & Robbins, J. M.
System:
The UNT Digital Library
NDA technology for uranium resource evaluation. [ONETRAN]
The following progress report describes the work performed during the first quarter on the contract for NDA Technology for Uranium Resource Evaluation. The initial phases of the work focused on gamma-ray calculations and computer code modifications in support of borehole logging measurements and surface gamma-ray surveys. The existing gamma-ray transport computer codes at Los Alamos Scientific Laboratory are being modified to give the energy group resolution desired for the uranium calculations. Monte Carlo computer calculations have been compared with the discrete ordinates ONETRAN code results for simple cases to gain confidence in the results. Preliminary calculations have been performed to investigate the applicability of transport and Monte Carlo computer calculations to uranium ore measurements. Feasibility studies are in progress to investigate the use of a photoneutron source for direct measurement of the uranium concentration surrounding a borehole. An /sup 124/Sb-Be neutron source was used for the initial laboratory test experiments, and a /sup 4/He gas proportional counter was used to count the induced prompt fission neutrons. A new approach is being investigated for producing photoneutrons by means of converting a beta-decay source to a bremsstrahlung spectrum.
Date:
February 1, 1977
Creator:
Menlove, H. O. (comp.)
System:
The UNT Digital Library
Critique of the Dixy Lee Ray Report, "The Nation's energy future"
None
Date:
February 3, 1975
Creator:
Anderson, C. J.; Moulthrop, P. H.; Ramsey, W. J.; Rubin, B. & Werth, G. C.
System:
The UNT Digital Library
Photo-induced cataphoretic isotope separation. Progress report, June 15, 1976--June 14, 1977. [Monoisotope light sources]
Initial results of studies of the feasibility of radiation-induced cataphoretic segregation of isotopes are summarized. More detailed feasibility calculations show that significant isotope separation efficiencies can be obtained for discharges at low pressure. This may make it desirable to use a buffer gas in the discharge in order to manipulate the electron energy distribution. Requirements for the properties of the buffer gas have been established. The experimental system for studying laser-induced cataphoretic separation of neon isotopes has been completed. Preliminary studies show that the system is capable of detecting less than 1% change in the Ne/sup 20//Ne/sup 22/ isotope ratio. It is anticipated that a systematic study can be made with respect to the photo-induced isotope separation efficiency in about three months. The other experimental system relates to the separation of mercury isotopes in a direct current gaseous discharge using radiation from external monoisotopic mercury light sources. Initial experimental feasibility studies of this technique are expected to be started after about three months. The ultra-high vacuum and gas handling system has been completed.
Date:
February 1, 1977
Creator:
Carruthers, J. A.; Chanin, L. M. & Oskam, H. J.
System:
The UNT Digital Library
Microinstabilities in Complex Magnetic Field Geometries and High- Beta. Sheared Sheath Structure. Progress Report, June 1, 1975--February 27, 1976
A new approach for the solution of the Vlasov equation for complex magnetic field geometries has been developed using operator techniques. The general approach is illustrated by determining the perturbed distribution function and density operator for the problem of shear stabilization of drift waves for transverse and arbitrary directions of propagation. The ensuing corrections to stability criteria of current theories are obtained for certain domains of physical parameters. Preliminary work on the integral equation approach to the dispersion relation has been initiated. As a prelude to the study of particle orbits in complex mirror geometries, the adiabatic and non-adiabatic behavior of a harmonic oscillator has been studied using operator methods. High-..beta.., high shear plasma sheath configurations have been studied with the full ion dynamics taken into account and electrons treated in the zero and first order approximation, in the ratio of the electron Larmor radius to the scale length. The resulting sheath structure equation in the lowest order approximation has been solved for certain entering ion distributions, and prepared for computer analysis for others. In this approximation the electron current parallel to magnetic field lines has to be assumed suppressed or predetermined. Equations in the next order approximation include the …
Date:
February 1, 1976
Creator:
Bakshi, P. & Kalman, G.
System:
The UNT Digital Library
Transient response of three-layered rings
Hamilton's principle is used to derive equations of motion for a linear elastic three-layered ring. The theory includes the effects of shear deformation and rotatory inertia in each layer and radial strain effects in the middle layer. A convenient computational technique is developed for transient response evaluation without resorting to finite-difference or finite-element approximations. A companion experimental study was conducted using three different rings. All rings had aluminum inner and outer layers, but each had a different low-modulus middle layer. Radial impulse loads, axisymmetric and distributed as a cosine over half the ring circumference, were applied to the outer ring surface, and the transient response was monitored with strain gages mounted on the aluminium layers. Measured strain-time histories were compared with theoretical calculations, and good agreement was obtained.
Date:
February 1, 1975
Creator:
Sagartz, M. J.
System:
The UNT Digital Library
Review of actinide-sediment reactions with an annotated bibliography
The annotated bibliography is divided into sections on chemistry and geochemistry, migration and accumulation, cultural distributions, natural distributions, and bibliographies and annual reviews. (LK)
Date:
February 10, 1976
Creator:
Ames, L. L.; Rai, D. & Serne, R. J.
System:
The UNT Digital Library
Maximally Concentrating Optics for Photovoltaic Solar Energy Conversion
The use of a two-stage concentrator with a fresnel lens primary and a non-imaging dielectric totally internally reflecting secondary, has unique advantages for photovoltaic concentration. This new design has a much larger acceptance angle than the conventional lens-cell concentrating system. In the continuation of this research, an optimally designed prototype which employs a 13.6-cm diameter flat fresnel tons as the primary focusing device, a dielectric compound hyperbolic concentrator (DCHC) as secondary and a 1-cm diameter high-concentration cell for electricity conversion has been built, tested and analyzed. Measurements under sunlight show that it has an angular acceptance of [plus minus]3.6 degrees, which is dramatically better than the [plus minus]0.5 degree achievable without a secondary concentrator. This performance agrees well with theoretical ray-tracing predictions. The secondary shows an optical efficiency of (91[plus minus]2)% at normal incidence. Combining with the primary fresnel tens which has an optical efficiency of (82[plus minus]2)%, tho two-stage system yields a total optical efficiency of (7l[plus minus]2)%. The measurement of the system electrical performance yielded a net electrical efficiency of 11.9%. No problems associated with non-uniform cell illumination were found, as evidenced by the excellent fill factor of (79[plus minus]2)% measured under concentration. The secondary geometrical properties and …
Date:
February 27, 1986
Creator:
Winston, R.; O'Gallagher, J. & Ning, X.
System:
The UNT Digital Library
Estimation of gas leak rates through very small orifices and channels. [From sealed PuO/sub 2/ containers under accident conditions]
As a result of a literature search, equations have been compiled for estimating the flow rates of pure gases through very small orifices and capillaries. Such equations might be useful in establishing upper limits of leak rates from sealed PuO/sub 2/ containers under accident conditions.
Date:
February 1, 1977
Creator:
Bomelburg, H. J.
System:
The UNT Digital Library
Supporting documents for LLL area 27 (410 area) safety analysis reports, Nevada Test Site
The following appendices are common to the LLL Safety Analysis Reports Nevada Test Site and are included here as supporting documents to those reports: Environmental Monitoring Report for the Nevada Test Site and Other Test Areas Used for Underground Nuclear Detonations, U. S. Environmental Protection Agency, Las Vegas, Rept. EMSL-LV-539-4 (1976); Selected Census Information Around the Nevada Test Site, U. S. Environmental Protection Agency, Las Vegas, Rept. NERC-LV-539-8 (1973); W. J. Hannon and H. L. McKague, An Examination of the Geology and Seismology Associated with Area 410 at the Nevada Test Site, Lawrence Livermore Laboratory, Livermore, Rept. UCRL-51830 (1975); K. R. Peterson, Diffusion Climatology for Hypothetical Accidents in Area 410 of the Nevada Test Site, Lawrence Livermore Laboratory, Livermore, Rept. UCRL-52074 (1976); J. R. McDonald, J. E. Minor, and K. C. Mehta, Development of a Design Basis Tornado and Structural Design Criteria for the Nevada Test Site, Nevada, Lawrence Livermore Laboratory, Livermore, Rept. UCRL-13668 (1975); A. E. Stevenson, Impact Tests of Wind-Borne Wooden Missiles, Sandia Laboratories, Tonopah, Rept. SAND 76-0407 (1976); and Hydrology of the 410 Area (Area 27) at the Nevada Test Site.
Date:
February 1, 1977
Creator:
Odell, B. N.
System:
The UNT Digital Library
Dynamical zoning within a Lagrangian mesh by use of DYN, a stellar pulsation code
None
Date:
February 1, 1977
Creator:
Castor, J. I.; Davis, C. G. & Davison, D. K.
System:
The UNT Digital Library
ANL ITER high-heat-flux blanket-module heat transfer experiments
An Argonne National Laboratory facility for conducting tests on multilayered slab models of fusion blanket designs is being developed; some of its features are described. This facility will allow testing under prototypic high heat fluxes, high temperatures, thermal gradients, and variable mechanical loadings in a helium gas environment. Steady and transient heat flux tests are possible. Electrical heating by a two-sided, thin stainless steel (SS) plate electrical resistance heater and SS water-cooled cold panels placed symmetrically on both sides of the heater allow achievement of global one-dimensional heat transfer across blanket specimen layers sandwiched between the hot and cold plates. The heat transfer characteristics at interfaces, as well as macroscale and microscale thermomechanical interactions between layers, can be studied in support of the ITER engineering design effort. The engineering design of the test apparatus has shown that it is important to use multidimensional thermomechanical analysis of sandwich-type composites to adequately analyze heat transfer. This fact will also be true for the engineering design of ITER.
Date:
February 1, 1992
Creator:
Kasza, K. E.
System:
The UNT Digital Library
Three-body approach to the single scattering optical potential. [Watson and KMT multiple scattering theory]
The single scattering optical potential was in the multiple scattering approaches of Watson and KMT. Since the kinematics of single scattering is three-body in nature, one builds a three-body model of this term. This approach can include the proper kinematics for the struck nucleon, the identity of the target nucleons, and the binding interaction of the struck nucleon. Integral equations of the Faddeev type are derived for both the Watson and KMT single scattering optical potentials. Unitarity relations are investigated and one observes that these relations can be expanded in order to identify the intermediate states responsible for the absorptive parts. The transition amplitudes to the inelastic states implicit in the model are extracted and evaluated. This permits one to understand the physical meaning of the imaginary part in precise terms. The same procedure is applied to the closure and impulse approximations for the single scattering term and their implicit inelastic states and reaction amplitudes are identified. These approximations are evaluated by analyzing the inelastic data. It is concluded that the impulse approximation to the Watson single scattering term should provide the best two-body approximation to a single-scattering optical potential.
Date:
February 1, 1977
Creator:
Tandy, P. C.; Redish, E. F. & Bolle, D.
System:
The UNT Digital Library
Explicit inverses of some special matrices (with a few computer programs)
Explicit inverses of some classes of special matrices are presented. In Section I, the tridiagonal matrices are discussed. In Section II a discussion is given of an algorithm due to Sherman and Morrison, which is useful in finding the inverse, when an explicit inverse is known for an unperturbed matrix. Section III presents inverses of some patterned matrices. Appendix A and Appendix B contain computer programs of some of the problems discussed in Sections I, II, and III. (auth)
Date:
February 1, 1976
Creator:
Uppuluri, V R. R. & Kirk, B L
System:
The UNT Digital Library
Sector 30 collimator radiation
The collimators at Sector 30 of the SLAC accelerator are designed to scrape off a significant fraction (e.g., {approximately}20%) of the SLC beam. The electromagnetic cascade shower that develops in the collimator, and in the scraper and waveguide downbeam, leads to very high radiation exposures of TV cameras (and other devices) located nearby. The collimator (point) source accounts for one-third of the dose and is best shielded by extending the radius of the copper scraper. Radiation from the waveguide accounts for the remaining two-thirds of the dose, and is difficult to shield since it is a line source. However, the spectrum from the waveguide is expected to be softer than that from the collimator. This paper discusses shielding of these sources.
Date:
February 22, 1990
Creator:
Namito, Y. (Ship Research Inst., Tokyo (Japan)); Nelson, W. R. & Benson, E.
System:
The UNT Digital Library
Improved real gas routines for Sandia's NASA Ames flow field program
The real gas subroutines in Sandia's version of the NASA Ames flow field code have been extensively revised. Using these modifications the required computer run time for a difficult high Mach number case has been reduced from 1330 seconds to 151 seconds. (auth)
Date:
February 1, 1976
Creator:
Eaton, R. R. & Larson, D. E.
System:
The UNT Digital Library