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Techniques for Monitoring Plutonium in the Environment (open access)

Techniques for Monitoring Plutonium in the Environment

Plutonium is one of the principal materials of both commercial and military nuclear power. It is produced primarily in fission reactors that contain uranium fuel, and its importance arises from the fact that a large portion of the plutonium produced is fissile: like uranium 235, the mass 239 and 241 isotopes of plutonium can be caused to fission by neutrons, including those with low energy. Because such fission events also release neutrons, substantial amounts of energy can be extracted from plutonium in a controlled or an explosive nuclear chain reaction. Now that commercial nuclear reactors provide a noticeable fraction of United States (and world) electrical energy, these reactors account for most plutonium production. For the most part, this material now remains in the irradiated fuel after removal from reactors, but should this fuel be reprocessed, the plutonium could be recycled to provide part and even most of the fissile content of fresh fuel. For the current generation of water-cooled reactors, the amount of plutonium to be recycled is substantial. In fast breeder reactors, designed to produce more fissile material than they destroy, considerably larger quantities of plutonium would be recycled. In other types of advanced reactors, particularly those which depend …
Date: July 1, 1978
Creator: Nero, A. V., Jr.
System: The UNT Digital Library
THE COVALENT BINDING OF ENANTIOMERIC BENZO [A] PYRENE DIOL EPOXIDES TO DOUBLE STRANDED DNA IS STEREOSELECTIVE (open access)

THE COVALENT BINDING OF ENANTIOMERIC BENZO [A] PYRENE DIOL EPOXIDES TO DOUBLE STRANDED DNA IS STEREOSELECTIVE

Reaction of optically pure (+) and (-) 7{beta},8{alpha}-dihydroxy-9{alpha},10{alpha}-epoxy-7,8,9.10-tetrahydrobenzo[a]pyrene with DNA in vitro yielded diastereomeric covalent adducts with the exocyclic amino groups of deoxyguanosine and deoxyadenosine. The ratio of two deoxyguanosine diastereomers derived by reacting the (+) and (-) hydrocarbons with native calf thymus and double stranded 0X174 DNA was 20:1 while reaction of the enantiomers with heat denatured calf thymus and single stranded 0X174 DNA resulted in a ratio near 1:1. In contrast, deoxyaadenosine diastereomer pairs were approximately 1:1 in all cases studied. The (+) and (-) enantiomers of the benzo[a]pyrene diol epoxide, therefore, interact asymmetrically with the guanine binding sites of double stranded but not single stranded polydeoxynucleotides. In contrast, reaction of the enantiomers with adenine is not stereoselective.
Date: July 1, 1978
Creator: Meehan, T. & Straub, K.
System: The UNT Digital Library
Mu - e Universality in Charged Current Neutrino Interactions in a Neon - H(2) Mixture (open access)

Mu - e Universality in Charged Current Neutrino Interactions in a Neon - H(2) Mixture

From an exposure of the Fermilab 15-ft Neon (64 atomic %)-H{sub 2} filled bubble chamber to a single-horn-focused {bar {nu}} beam, they have found 60 e{sup -}X and 35 e{sup +}X events, which they compare with 227 {mu}{sup -}X and 202 {mu}{sup +}X events. No statistically significant departures from {mu}-e universality are seen.
Date: July 1, 1978
Creator: Ballagh, H. C.; Bingham, H. H.; Bosetti, P.; Fretter, W. B.; Gee, D.; Grivaz, J. -F. et al.
System: The UNT Digital Library
Department of Energy's Solar Update. Four Regional Conferences Highlighting the Objectives, Plans, and Experience of the National Commercial Solar Heating and Cooling Demonstration Program and the National Solar Data Program (open access)

Department of Energy's Solar Update. Four Regional Conferences Highlighting the Objectives, Plans, and Experience of the National Commercial Solar Heating and Cooling Demonstration Program and the National Solar Data Program

These proceedings represent the overview and project papers made available to all the participants at each of the regional conferences. Papers not available at time of publication, and additional materials, including a summary and analysis of the Workshop/Panel Sessions are included in the complete proceedings CONF-780701--(Rev.) for which individual abstracts were prepared for each paper. (MHR)
Date: July 1, 1978
Creator: unknown
System: The UNT Digital Library
Proceedings of the isotope separator on-line workshop (open access)

Proceedings of the isotope separator on-line workshop

Separate abstracts were prepared for thirteen of the papers in this volume. The remaining three have already been cited in ERA, and can be located by reference to the entry CONF-771078-- in the Report Number Index. (RWR)
Date: July 1, 1978
Creator: Chrien, R E
System: The UNT Digital Library
Specimen-exchange device for an ultra-high vacuum atom-probe field-ion microscope (open access)

Specimen-exchange device for an ultra-high vacuum atom-probe field-ion microscope

A specimen-exchange device is described for an ultra-high vacuum field-ion microscope (FIM). This device completely eliminates the long pump-down period that is required if the FIM chamber is brought back to atmospheric pressure. The pressure in an air-lock is reduced to 10/sup -6/ Torr before the exchange takes place and the pressure in the FIM chamber remains below 10/sup -7/ Torr during the exchange and it drops to less than 3 x 10/sup -9/ Torr within 15 minutes after the exchange.
Date: July 1, 1978
Creator: Wagner, Alfred; Hall, Thomas M. & Seidman, David N.
System: The UNT Digital Library
Measuring social risk and determining its acceptability (open access)

Measuring social risk and determining its acceptability

The implementation of a nuclear waste management technology raises several issues concerning the regulation of social risk. This paper presents a decision analytic approach to resolving some of those issues. A methodology for developing a radiological risk measure is presented, and several approaches to defining acceptable levels of that risk measure are considered. The methodology presented is oriented toward the development of radiological performance objectives for use as guidance in the drafting of regulations.
Date: July 14, 1978
Creator: Lathrop, J.W.
System: The UNT Digital Library
Estimates of time-dependence fatigue behavior of type 316 stainless steel subject to irradiation damage in fast breeder and fusion power reactor systems. [Fluence 1--2. 63 x 10/sup 26/ n/m/sup 2/ (E > 0. 1 MeV/ at 593/sup 0/C] (open access)

Estimates of time-dependence fatigue behavior of type 316 stainless steel subject to irradiation damage in fast breeder and fusion power reactor systems. [Fluence 1--2. 63 x 10/sup 26/ n/m/sup 2/ (E > 0. 1 MeV/ at 593/sup 0/C]

Cyclic lives obtained from strain controlled fatigue tests at 593/sup 0/C from specimens irradiated to a fluence of 1 to 2.63 x 10/sup 26/ n/m/sup 2/ (E greater than 0.1 MeV) were compared to predictions based on the method of strainrange partitioning. When appropriate tensile and creep-rupture ductilities were employed reasonably good estimates of the influence of hold periods and irradiation damage on the fully reversed fatigue life of type 316 stainless steel could be made. Ductility values for 20 percent cold-worked type 316 stainless steel specimens irradiated in a mixed spectrum fission reactor were used to estimate fusion reactor first wall lifetime. The ductility values were from irradiations that simulate the environment of the first wall of a fusion reactor. Neutron wall loadings ranging from 2 to 5 MW/m/sup 2/ were used. Results, although conjectural because of the many assumptions, tended to show that 20 percent cold-worked type 316 stainless steel could be used as a first wall material meeting a 7.5 to 8.5 MW-year/m/sup 2/ lifetime goal provided the neutron wall loading does not exceed more than about 2 MW/m/sup 2/. Results were obtained for an air environment, and it is expected that the actual vacuum environment will …
Date: July 10, 1978
Creator: Brinkman, C.R.; Liu, K.C. & Grossbeck, M.L.
System: The UNT Digital Library
Picosecond phase shift measurements at 358 MHz using synchrotron radiation (open access)

Picosecond phase shift measurements at 358 MHz using synchrotron radiation

Properties of synchrotron radiation from SPEAR are reviewed. The power--frequency spectrum of source and photomultiplier tube is measured with a spectrum analyzer. The decay time of a single fluorescent species can be deduced by measuring the phase delay between excitation and fluorescence radiation modulated at a single suitable frequency. It is possible to characterize completely the time (impulse) response or the complex frequency response of a linear system with only phase measurements. A number of test experiments were made by using apparatus designed for time-resolved fluorescence emission anisotropy studies of tryptophan in proteins. Phase shifts were produced by insertion of water-filled quartz cells into the beam and by the introduction of a thick glass slab. The total optical path length could also be altered by linear motion of the phototube. The results yielded 4.7 +- 0.5 degrees per cm of motion. It was concluded that this procedure can be used to study short atomic and molecular fluorescence lifetimes. 3 figures. (RWR)
Date: July 1, 1978
Creator: Sabersky, A.P. & Munro, I.H.
System: The UNT Digital Library
Intrusion detection sensors (open access)

Intrusion detection sensors

Intrusion detection sensors are an integral part of most physical security systems. Under the sponsorship of the U.S. Department of Energy, Office of Safeguards and Security, Sandia Laboratories has conducted a survey of available intrusion detection sensors and has tested a number of different sensors. An overview of these sensors is provided. This overview includes (1) the operating principles of each type of sensor, (2) unique sensor characteristics, (3) desired sensor improvements which must be considered in planning an intrusion detection system, and (4) the site characteristics which affect the performance of both exterior and interior sensors. Techniques which have been developed to evaluate various intrusion detection sensors are also discussed.
Date: July 1, 1978
Creator: Williams, J.D.
System: The UNT Digital Library
Central collisions of relativistic nuclei. [Cross sections, partial data analysis, yield 250 MeV/nucleon to 2. 1 GeV/nucleon] (open access)

Central collisions of relativistic nuclei. [Cross sections, partial data analysis, yield 250 MeV/nucleon to 2. 1 GeV/nucleon]

New data for relativistic heavy ion collisions are presented for the emitted protons and pions, and for the average multiplicities and angular correlations of the charged particles. Comparisons with several different theoretical approaches are made including the nuclear firestreak model. It appears that there is a group of nucleons with randomized motion and high temperature. The stage is reached where one is beginning to look for effects due to the expansion of a compressed region. 16 references.
Date: July 1, 1978
Creator: Poskanzer, A.M.
System: The UNT Digital Library
Preliminary environmental assessments of known geothermal resource areas in the United States (open access)

Preliminary environmental assessments of known geothermal resource areas in the United States

The basic purpose of the Geothermal Overview Project is to identify, summarize, and assess the environmental issues of the top priority KGRAs from among the approximately 40 KGRAs currently identified by the Division of Geothermal Energy, DOE, as having high possibilities for commercial development. The Geothermal Overview Project addresses issues pertaining to air quality, ecosystems quality, noise effects, geological effects, water quality, socioeconomic effects, and health effects. For each KGRA the following functions are accomplished: identification of key issues; inventory of all available data; analysis and assessment of available data; and, identification of what additional information is required for adequate assessments. Studies at the Geysers-Calistoga KGRA in Northern California are used as an example.
Date: July 1, 1978
Creator: Phelps, P. L.; Ermak, D. L.; Anspaugh, L. R.; Jackson, C. D. & Miller, L. A.
System: The UNT Digital Library
CUBE (Computer Use By Engineers) symposium abstracts. [LASL, October 4--6, 1978] (open access)

CUBE (Computer Use By Engineers) symposium abstracts. [LASL, October 4--6, 1978]

This report presents the abstracts for the CUBE (Computer Use by Engineers) Symposium, October 4, through 6, 1978. Contributors are from Lawrence Livermore Laboratory, Los Alamos Scientific Laboratory, and Sandia Laboratories.
Date: July 1, 1978
Creator: Ruminer, J.J. (comp.)
System: The UNT Digital Library
Motion of electron-hole drops in Ge (open access)

Motion of electron-hole drops in Ge

Using a new experimental technique based on hysteresis, the time development of the size of a localized packet of electronhole drops (EHD) in a spatially uniform free exciton gas near threshold is measured for times approximately 10/sup 4/ sec. No significant motion is found, determining an upper limit D approximately < 10/sup -9/cm/sup 2/sec/sup -1/ to the possible EHD diffusion constant.
Date: July 1, 1978
Creator: Westervelt, R. M.; Culbertson, J. C. & Black, B. S.
System: The UNT Digital Library
Studies of tandem mirror confinement (open access)

Studies of tandem mirror confinement

This paper describes a number of physics studies relevant to tandem mirror confinement. We give the basic axial confinement laws and show that T/sub e/ depends critically upon end loss. Sufficient central-cell end loss can stabilize the drift-cyclotron loss-cone mode in the plugs, although the resultant T/sub e/ scaling is too slow for reactors. Minimum-B plugs stabilize flute MHD- and rotation-driven modes; local ballooning sets limits on ..beta.. > or equal to 0.5. Proper magnetic symmetry is important for good drift confinement. For small increases in the total injected power, supplementary ion-cyclotron r.f. heating can halve the neutral-beam energy required to maintain plug densities.
Date: July 10, 1978
Creator: Baldwin, D. E.; Cohen, R. H.; Foote, J. H.; Hall, L. S.; Kaiser, T. B.; Logan, B. G. et al.
System: The UNT Digital Library
Floating dry cooling: a competitive alternative to evaporative cooling in a binary cycle geothermal power plant (open access)

Floating dry cooling: a competitive alternative to evaporative cooling in a binary cycle geothermal power plant

The application of the floating cooling concept to non-evaporative and evaporative atmospheric heat rejection systems was studied as a method of improving the performance of geothermal powerplants operating upon medium temperature hydrothermal resources. The LBL thermodynamic process computer code GEOTHM is used in the case study of a 50 MWe isobutane binary cycle power plant at Heber, California. It is shown that operating a fixed capacity plant in the floating cooling mode can generate significantly more electrical energy at a higher thermodynamic efficiency and reduced but bar cost for approximately the same capital investment. Floating cooling is shown to benefit a plant which is dry cooled to an even greater extent than the same plant operating with an evaporative heat rejection system. Results of the Heber case study indicate that a dry floating cooling geothermal binary cycle plant can produce energy at a bus bar cost which is competitive with the cost of energy associated with evaporatively cooled systems.
Date: July 1, 1978
Creator: Pines, H.S.; Green, M.A.; Pope, W.L. & Doyle, P.A.
System: The UNT Digital Library
Structure of a black chrome solar selective surface (open access)

Structure of a black chrome solar selective surface

The structure of ''CHROM-ONYX'' type of black chrome/metal selective absorber was studied to gain a better understanding of its influence upon the mechanism of wavelength selectivity. Spectral reflectance measurements were performed on seven samples. The best selectivity was found by these measurements to be 0.7 micron of black chrome on nickel and 1.0 micron of black chrome on copper. Both scanning and transmission electron microscopy were employed to study microstructure and chemical composition. As a result of the combined studies, some effects of black chrome thickness and the metallic substrate were determined. It was found that black chrome consisted of a very fine metallic distribution of particles of chromium, possibly suspended within a matrix of an oxide of chromium. This combination was, in turn, agglomerated into larger particles within the 0.05 to 0.3 micron size range. These larger particles formed a network which constituted the surface coating.
Date: July 1, 1978
Creator: Lampert, C.M.
System: The UNT Digital Library
Field reversal in mirror machines (open access)

Field reversal in mirror machines

This report discusses some of the physics issues anticipated in field-reversed mirrors. The effect of current cancellation due to electrons is described. An estimate is made of the required impurity level to maintain a field-reversed configuration. The SUPERLAYER code is used to simulate the high-..beta.. 2XIIB results, and favorable comparisons require inclusion of quasilinear RF turbulence. Impact of a quadrupole field on field-line closure and resonant transport is discussed. A simple self-consistent model of ion currents is presented. Conditions for stability of field-reversed configurations to E x B driven rotations are determined.
Date: July 10, 1978
Creator: Pearlstein, L. D.; Anderson, D. V. & Boozer, A. H.
System: The UNT Digital Library
New neutron simulation capabilities provided by the Sandia Pulse Reactor (SPR-III) and the Upgraded Annular Core Pulse Reactor (ACPR) (open access)

New neutron simulation capabilities provided by the Sandia Pulse Reactor (SPR-III) and the Upgraded Annular Core Pulse Reactor (ACPR)

The paper briefly describes the nuclear reactor facilities at Sandia Laboratories which are used for simulating nuclear weapon produced neutron environments. These reactor facilities are used principally in support of continuing R and D programs for the Department of Energy/Office of Military Application (DOE/OMA) in studying the effects of radiation on nuclear weapon systems and components. As such, the reactors are available to DOE and DOD agencies and their contractors responsible for the radiation hardening of advanced nuclear weapon systems. Emphasis is placed upon two new reactor simulation sources; the Sandia Pulse Reactor-III (SPR-III) Facility which enhances the neutron exposure volume capabilities over those presently available with the existing SPR-II Facility, and the Upgraded Annular Core Pulse Reactor (ACPR) Facility which enhances the neutron exposure capabilities over those of the former ACPR Facility.
Date: July 1, 1978
Creator: Choate, L.M. & Schmidt, T.R.
System: The UNT Digital Library
High-temperature electronics workshop: progress in the development of microelectronics for the 500/sup 0/C environment (open access)

High-temperature electronics workshop: progress in the development of microelectronics for the 500/sup 0/C environment

This workshop proceedings describes the status of the Los Alamos Scientific Laboratory (LASL) and University of Arizona programs in the development of high-temperature microelectronic devices for geothermal well-logging applications.
Date: July 1, 1978
Creator: McCormick, J.B. (ed.)
System: The UNT Digital Library
Noise limitations of the DC SQUID (open access)

Noise limitations of the DC SQUID

The dc SQUID (Superconducting Quantum Interference Device) is a very sensitive detector of changes in magnetic flux, and is becoming widely used as a magnetometer and as a voltmeter. The paper summarizes the noise limitations of the device and makes projections of its ultimate performance. A more detailed account of the work is to appear elsewhere.
Date: July 1, 1978
Creator: Clarke, J.
System: The UNT Digital Library
Enhanced filtration program at LLL. A progress report. (open access)

Enhanced filtration program at LLL. A progress report.

As part of Lawrence Livermore Laboratory's Enhanced Filtration Program, we are investigating the use of an externally applied electric field to improve the performance of fibrous filters. Our objective in this program is to develop filtration systems for the nuclear industry that will reduce the cost and volume of nuclear waste associated with present systems. We have developed a new theory of the electrostatic filter that is consistent with experimental tests made during transient and steady-state conditions. For these tests, we used ac and dc electric fields, insulated and noninsulated electrodes, and conducting and nonconducting filter media; all tests were conducted in our small-scale 25 l/s test system, using sodium chloride aerosols. Our theory employs a new mechanism based on the attraction between charged particles and charged fibers in addition to the previously proposed mechanism based on the attraction between charged particles and polarized fibers. In this theory, fibers are charged when charged particles deposit on them. We have also developed a theoretical model that explains the increase in filter efficiency and pressure drop when particles load on the filter. The filter loading tests we conducted to evaluate this model verify its accuracy to a remarkable degree. By using the …
Date: July 28, 1978
Creator: Bergman, W.; Taylor, R. D.; Miller, H. H.; Bierman, A. H.; Hebard, H. D.; daRoza, R. A. et al.
System: The UNT Digital Library
Reduction of irradiation-induced creep by point defect trapping (open access)

Reduction of irradiation-induced creep by point defect trapping

The theory of point defect trapping was applied to predict the effect of solutes on the steady-state dislocation climb creep rate. Vacancy loops generated in the cascades of point defect production by heavy particles were included. It is shown that the effect of vacancy loops on the creep rate is mathematically equivalent to a simultaneous reduction in the vacancy trapping rate at solutes as well as in the free point defect generation rate and recombination coefficient. These parameters are reduced by the ratio of the sink strength without vacancy loops to the total sink strength. Solute trapping and vacancy loops do not reduce the unperturbed creep rates by more than an order of magnitude for the parametric range considered.
Date: July 10, 1978
Creator: Mansur, L. K. & Wolfer, W. G.
System: The UNT Digital Library
Energetics of semi-catalyzed-deuterium, light-water-moderated, fusion-fission toroidal reactors (open access)

Energetics of semi-catalyzed-deuterium, light-water-moderated, fusion-fission toroidal reactors

The semi-catalyzed-deuterium Light-Water Hybrid Reactor (LWHR) comprises a lithium-free light-water-moderated blanket with U/sub 3/Si fuel driven by a deuterium-based fusion-neutron source, with complete burn-up of the tritium but almost no burn-up of the helium-3 reaction product. A one-dimensional model for a neutral-beam-driven tokamak plasma is used to determine the operating modes under which the fusion energy multiplication Q/sub p/ can be equal to or greater than 0.5. Thermonuclear, beam-target, and energetic-ion reactions are taken into account. The most feasible operating conditions for Q/sub p/ approximately 0.5 are <n/sub e/>tau/sub E/ = 2 to 4 x 10/sup 14/ cm/sup -3/s, <T/sub e/> = 10 to 20 keV, and E/sub beam/ = 500 to 1000 keV, with approximately 40% of the fusion energy produced by beam-target reactions. Illustrative parameters of LWHRs are compared with those of an ignited D-T reactor.
Date: July 1, 1978
Creator: Jassby, D. L.; Towner, H. H.; Greenspan, E.; Schneider, A.; Misolovin, A. & Gilai, D.
System: The UNT Digital Library