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Tumor production in Syrian hamsters following inhalation of PuO/sub 2/--ZrO/sub 2/ aerosol (open access)

Tumor production in Syrian hamsters following inhalation of PuO/sub 2/--ZrO/sub 2/ aerosol

Syrian golden hamsters of both sexes were exposed to aerosols of ZrO/sub 2/ containing PuO/sub 2/. The starting material in the aerosol generator also had a small amount of /sup 57/Co added as a tracer. The mixture of all three constituents was nebulized and the droplets passed through a heating column at 1000/sup 0/C. Aerosol sampling was accomplished with a cascade impactor and electrostatic precipitator. The median aerodynamic diameters in all inhalation runs were approximately 2 ..mu..m with a geometric standard deviation of 2. One exposed group of 60 hamsters had 6-day lung burdens averaging 100 nCi. This group had a lung tumor incidence of 44% with an even distribution of adenomas and carcinomas. Two other groups had average 6-day lung burdens of 80 to 90 nCi plus 55 nCi of intravenously injected spheres localized in the lung. These animals had tumor incidences of approximately 30%.
Date: January 1, 1978
Creator: Thomas, R. G. & Smith, D. M.
System: The UNT Digital Library
Thorium fuel cycles for LWRs: fuel diversion assessments and recycle requirements (open access)

Thorium fuel cycles for LWRs: fuel diversion assessments and recycle requirements

A number of fuel cycles have been proposed for evaluation in the nonproliferation alternative systems assessment program. Among these systems are light water reactors (LWR) operating on the thorium-uranium cycle or the plutonium-thorium cycle either inside or outside energy centers. These proposals support the President's nuclear power policy of accelerating research into alternative fuel cycles that do not permit direct access to materials usable for nuclear weapons but still retain the benefits of nuclear power. Reprocessing and refabrication (often referred to as the ''back cycle'') constitute a portion of the overall fuel cycle and represent potential access points to fissionable materials, which, in many cases, may be in a rather attractive form for diversion. These operations for LWR thorium-uranium and plutonium-thorium fuels were analyzed to assess and rate the diversion or proliferation potential of each major operation. Reprocessing and refabrication evaluations per se constitute insufficient data for rating the acceptability of an entire fuel cycle and must be considered along with reactor analysis, environmental data, resource utilization, and political factors. Each back cycle operation has been evaluated according to needed development, material location, material description, convertibility and radiation hazard. Needed development relates to the state of the art of the …
Date: January 1, 1978
Creator: Carter, W. L.; Rainey, R. H. & Johnson, D. R.
System: The UNT Digital Library
Technique for dynamic range reduction for Landsat ratio images (open access)

Technique for dynamic range reduction for Landsat ratio images

The LANDSAT ratio image, obtained by dividing one MSS band by another on a point-by-point basis, has become an established tool for geological applications over the past several years. Display of such images can be difficult since the dynamic range can extend from zero to infinity. A scheme for dynamic range reduction, based on a mathematical model of the multispectral image, is presented. It can be implemented on stand-alone digital image processing systems as well as general purpose computers. This technique also has potential application in machine classification of geological data. Digital image processing examples are presented in which this new scheme is compared with other commonly used techniques for dynamic range reduction.
Date: January 1, 1978
Creator: Wecksung, G.W. & Breedlove, J.R. Jr.
System: The UNT Digital Library
Radiation instrumentation (open access)

Radiation instrumentation

Separate abstracts have been prepared for items within the scope of the energy data base.
Date: January 1, 1978
Creator: Wadman, W.W. III (ed.)
System: The UNT Digital Library
Mirror hybrid reactor studies (open access)

Mirror hybrid reactor studies

The hybrid reactor studies are reviewed. The optimization of the point design and work on a reference design are described. The status of the nuclear analysis of fast spectrum blankets, systems studies for fissile fuel producing hybrid reactor, and the mechanical design of the machine are reviewed. (MHR)
Date: January 19, 1978
Creator: Bender, D.J.
System: The UNT Digital Library
Dielectric strengths of new gases and gas mixtures (open access)

Dielectric strengths of new gases and gas mixtures

It is emphasized that the most effective gaseous dielectrics are gas mixtures with components chosen on the basis of fundamental physicochemical knowledge, especially on low-energy electron-molecule interactions. On the basis of such lnowledge, especially on electron attachment and electron slowing down, a number of new gases and gas mixtures have been found with breakdown strengths superior to pure SF/sub 6/. These include the unitary gases c-C/sub 4/F/sub 8/ (perfluorocyclobutane), C/sub 4/F/sub 8/ (perfluorobutene-2), C/sub 4/F/sub 6/ (perfluoro-2-butyne), C/sub 6/F/sub 10/ (perfluorocyclohexene), C/sub 5/F/sub 8/ (perfluorocyclopentene), and C/sub 6/F/sub 12/ (perfluorodimethylcyclobutane), and the multicomponent gas mixtures 20% C/sub 4/F/sub 6/ + 80% SF/sub 6/, 40% C/sub 4/F/sub 6/ + 60% N/sub 2/, 50% C/sub 4/F/sub 6/ + 50% SF/sub 6/, and 30% C/sub 4/F/sub 6/ + 20% SF/sub 6/ + 50% N/sub 2/ with DC breakdown strengths relative to SF/sub 6/ of 1 equal to 1.4, 1.8, 2.2, 2.1, 2.2, 2,4, 1.3, 1.4, 1.75, and 1.33, respectively. Findings on these and other systems are presented and discussed. Also discussed are results on the dielectric strengths of some of the above new gases measured with cylindrical electrode geometries using different center conductor diameters. Finally, findings on the initial decomposition products of some …
Date: January 1, 1978
Creator: James, D.R.; Christophorou, L.G.; Pai, R.Y.; Pace, M.O.; Mathis, R.A.; Sauers, I. et al.
System: The UNT Digital Library
Liquid waste handling facilities for a conceptual LWR spent fuel reprocessing complex (open access)

Liquid waste handling facilities for a conceptual LWR spent fuel reprocessing complex

The waste evaporator systems and the methods for evaporating the liquid wastes of various radioactivity levels are discussed. After the liquid wastes are evaporated and nitric acid is recovered the high-level liquid waste is incorporated into borosilicate glass and the intermediate-level liquid waste into concrete for final disposal. (LK)
Date: January 1, 1978
Creator: Witt, D.C. & Bradley, R.F.
System: The UNT Digital Library
Fiber optics and microprocessors: a control-system solution for the laser-fusion environment (open access)

Fiber optics and microprocessors: a control-system solution for the laser-fusion environment

The use of fiber optics and microprocessors in a distributed computer control system for a 100-kJ CO/sub 2/ laser fusion facility is described. Gas-laser control systems must operate in an environment in which megavolt Marx circuits generate megampere discharges in the laser amplifiers, with attendant high electromagnetic fields. By linking the distributed controls with fiber optics the adverse effect of these fields on the hard-wired controls is mimimized, and the additional advantage of ground isolation gained. Fiber-optic subsystems and interfaces include low-error-rate digital communication links between computers; nanosecond timing and trigger links; fiber-optic parameter monitors with dc-to-10 MHz bandwidths; binary fiber-optic power control for valves, motors, and contactors; and binary fiber-optic status interfaces to monitor the system response to control outputs.
Date: January 1, 1978
Creator: Thuot, M.E.
System: The UNT Digital Library
Introduction to albedo neutron dosimeters (open access)

Introduction to albedo neutron dosimeters

The design, operation, calibration, and performance of albedo neutron dosimeters are discussed. An albedo neutron dosimeter is designed to measure the flux of thermal neutrons which leave the body when a person is exposed to fast energy neutrons. The fast neutrons are scattered and moderated in the body, and many have lost most of their initial energy and emerge as thermal neutrons. The albedo neutron dosimeter is designed to detect this flux of thermal neutrons by using a thermal neutron detector. This could be any type of thermal neutron detector but in practical applications lithium fluoride (LiF) thermoluminescence dosimeters (TLDs) are most frequently used. Various types of albedo neutron dosimeters are described. (WHK)
Date: January 16, 1978
Creator: Hankins, D.E.
System: The UNT Digital Library
Tapered fluidized-bed bioreactor: an improved device for continuous cultivation (open access)

Tapered fluidized-bed bioreactor: an improved device for continuous cultivation

The bioreactor concept utilizing a tapered fluidized bed has shown considerable promise for use in bioprocesses where the biological agents can be immobilized on a fluidizable solid phase, but the operating characteristics of such a reactor are not yet fully understood. A simple mathematical model (steady state, plug flow conditions) has been developed and tested with experimental data, and calculated values compare favorably with experimental values. A more complete and presumably more valid mathematical model incorporating void volume changes and particle size distribution is being developed.
Date: January 1, 1978
Creator: Pitt, Jr., W. W.; Hancher, C. W.; Scott, C. D. & Hsu, H. W.
System: The UNT Digital Library
Simple empirical method for estimating the performance of a passive solar heated building of the thermal storage wall type (open access)

Simple empirical method for estimating the performance of a passive solar heated building of the thermal storage wall type

Two methods are presented for estimating the annual solar heating performance of a building utilizing a passive thermal storage wall of the Trombe wall or water wall type with or without night insulation and with or without a reflector. The method is accurate to +-3% as compared with hour-by-hour computer simulations.
Date: January 1, 1978
Creator: Balcomb, J.D. & McFarland, R.D.
System: The UNT Digital Library
Investigation of cooling coil corrosion in storage tanks for radioactive waste (open access)

Investigation of cooling coil corrosion in storage tanks for radioactive waste

The high frequency of cooling coil leaks observed in high-heat waste storage tanks soon after sludge removal operations is attributed to pitting, according to laboratory corrosion studies. Experiments show that the most likely series of events leading to coil leakage is (1) excessive dilution of basic nitrite in the supernate, (2) initiation of attack in crevices due to oxygen depletion cells, and (3) acceleration of the attack by sulfate dissolved from the sludge. When sludge was slurried with water, the interstitial liquid was diluted. Nitrite, the anodic inhibitor that prevented attack on coils and tanks in normal operation when its concentration was 0.5 to 3.0M, could accelerate attack when diluted to 10/sup -4/ to 10/sup -3/M. Attack was presumably initiated at oxygen depletion cells. The presence of sulfate, leached from the sludge, produced a conductive solution that could produce high current densities at the corroding steel surface. The proposed series of events leading to coil leakage agrees with the observations previously made on one leaking coil removed from Tank 2F after sludge removal in 1967. Examination revealed pitting that had originated on the outside of the coils. This pitting was attributed to oxygen depletion cells in coil crevices. To prevent …
Date: January 1, 1978
Creator: Ondrejcin, R.S.
System: The UNT Digital Library
Impacts of the national energy programme on solar economics (open access)

Impacts of the national energy programme on solar economics

The National Energy Plan (NEP) sets as a goal the use of solar energy in two and a half million homes in 1985. A key provision of the NEP (as well as congressional alternatives) provides for the subsidization of solar equipment. The extent to which these subsidies (income tax credits) might offset the impact of continued energy-price control is examined. Regional prices and availability of conventional energy sources (oil, gas, and electricity) were compiled to obtain a current and consistent set of energy prices by state and energy type. These prices are converted into equivalent terms ($/10/sup 6/ Btu) that account for combustion and heat-generation efficiencies. Projections of conventional-fuel price increases (or decreases) are made under both the NEP scenario and a projected scenario where all wellhead price controls are removed on natural gas and crude oil production. The economic feasibility (life-cycle cost basis) of solar energy for residential space heating and domestic hot water is examined on a state-by-state basis. Solar-system costs are developed for each state by fraction of Btu heating load provided. The total number of homes, projected energy savings, and sensitivity to heating loads, alternative energy costs, and prices are included in the analysis.
Date: January 1, 1978
Creator: Ben-David, S.; Noll, S.; Roach, F. & Schulze, W.
System: The UNT Digital Library
Germanium detector system for the detection of transuranics at low-activity concentrations in soil. [/sup 241/Am, /sup 240/Pu, /sup 239/Pu, /sup 238/U, /sup 232/Th] (open access)

Germanium detector system for the detection of transuranics at low-activity concentrations in soil. [/sup 241/Am, /sup 240/Pu, /sup 239/Pu, /sup 238/U, /sup 232/Th]

A photon spectroscopy system is described which is designed for the detection of plutonium and /sup 241/Am in soil samples with a minimum turnaround time. Quantification is based upon the 60-keV gamma emitted in /sup 241/Am decay and upon the uranium L x-rays (energies from 13 to 22 keV) emitted by plutonium isotopes during alpha decay. The detector is a single-crystal, intrinsic-germanium-planar detector with a surface area of 21 cm/sup 2/. Sensitivity is increased by incorporating a detector window with a larger than normal surface area. This optimized window size was established by Monte Carlo calculations. For small, Petri-dish samples, detection limits at the 3 sigma level for a 4-hr counting time are better than 4 pCi/g for plutonium and better than 0.05 pCi/g for /sup 241/Am. The specifications, performance, and cost of the system are discussed.
Date: January 1, 1978
Creator: West, L.; Umbarger, C.J. & Dempsey, T.
System: The UNT Digital Library
Geothermal environmental seminar-'78 (open access)

Geothermal environmental seminar-'78

Thirty-seven papers are included. Two were abstracted for EDB previously. Abstracts were prepared for the remaining thirty-five. (MHR)
Date: January 1, 1978
Creator: Tucker, F. L. & Tanner, L. R.
System: The UNT Digital Library
Initial results from the first Los Alamos hot dry rock energy system (open access)

Initial results from the first Los Alamos hot dry rock energy system

The pressurized-water loop for extraction of natural heat from dry crustal rock is, as this is written, eight weeks into its initial long-term continuous circulation test. During most of this time, flow-impedance through the man-made fracture system has decreased continuously so that, with a nearly constant pressure difference between injection and recovery wells, flow rate has increased steadily to the maximum capacity of the surface piping--about 16 liters per second. Temperature of water entering the recovery well from the fracture system at first decreased rapidly; however, the rate of decrease has diminished steadily, and temperature is now nearly constant at about 94/sup 0/C. The increase in flow rate so far has overwhelmed the temperature decrease, so that rate of heat extraction has approximately doubled, to above 5 MW. Composition of the recirculated water apparently has not yet stabilized, but total dissolved solids (chiefly silica) is relatively low and rate of water loss from the loop has decreased to about 2% of the total flow rate. Both the effective volume and the effective surface area of the fracture system have recently increased significantly which, together with stabilization of the effluent temperature, suggests that thermal contraction is having its expected effect on …
Date: January 1, 1978
Creator: Smith, M.C.
System: The UNT Digital Library
Hot dry rock, an alternate geothermal energy resource: a challenge for instrumentation (open access)

Hot dry rock, an alternate geothermal energy resource: a challenge for instrumentation

The natural internal heat from the Earth is one of the cleanest, nearly inexhaustible energy sources. The hot dry rock that composes most of the Earth's crust has the potential of becoming one of the largest reservoirs of energy economically available in the near future. The Los Alamos Scientific Laboratory, for the past five years, has been working toward exploiting this very abundant, clean energy source. The LASL technique to demonstrate the technical and economic feasibility of extracting heat from the hot dry rock source depends upon the connection of two deep boreholes drilled into impermeable precambrian granite where the temperature approaches 200/sup 0/C. The boreholes are connected by a system of hydraulic-produced fractures. Cold water flowing down the deeper hole will be heated by the hot rock and will be brought to the surface through the second hole. The hot water will be circulated through a closed-loop heat exchanger. The first phase of operating the 10 MW(t) heat extraction experiment will be conducted to determine the mechanical, physical and chemical properties of the reservoir and heat exchange system. Environmental effects will be carefully monitored. For optimum extraction of energy from this man-made geothermal reservoir, it is vital that the …
Date: January 1, 1978
Creator: Dennis, B.R. & Horton, E.H.
System: The UNT Digital Library
Removal of uv-induced pyrimidine dimers from the replicated and unreplicated DNA of human fibroblasts (open access)

Removal of uv-induced pyrimidine dimers from the replicated and unreplicated DNA of human fibroblasts

Excision repair in uv irradiated human fibroblasts has been examined in portions of DNA replicating after irradiation versus those remaining unreplicated. Two approaches, one using a uv-endonuclease to estimate pyrimidine dimers remaining in DNA, the other using density labeling to measure excision resynthesis, indicate that the extent of repair is the same for both replicated and unreplicated DNA.
Date: January 1, 1978
Creator: Waters, R.
System: The UNT Digital Library
Superconductor development program at Lawrence Livermore Laboratory (open access)

Superconductor development program at Lawrence Livermore Laboratory

Winding of a Nb--Ti test coil at the Lawrence Livermore Laboratory is nearly complete. The conductor in this coil operates in a maximum field of 7.5 T and provides the 2-T field required by the Mirror Fusion Test Facility. Nb/sub 3/Sn multifilamentary conductors, made using the ''bronze'' technique, appear capable of providing the higher fields needed by commercial reactors.
Date: January 19, 1978
Creator: Cornish, D.N.
System: The UNT Digital Library
Computer graphics for extracting information from data (open access)

Computer graphics for extracting information from data

Computer graphics which are useful for displaying and analyzing data are presented. Many classical and several newly developed graphical techniques in statistical data analysis are presented for small univariate and multivariate data sets. These include histograms, empirical density functions, pie charts, contour plots, a discriminant analysis display, cluster analysis, Chernoff ''faces,'' Andrews' sine curves, three-dimensional plots, and probability plots. Recent advances in data collection technology and computer data base management systems have made it imperative to utilize computer graphics for large data sets. Several innovative graphical techniques are presented to handle this situation. Spatial relationships among the data (particularly geographic data) are difficult to conceptualize. Several cartographic techniques are presented which enhance the understanding of these spatial relationships within the data.
Date: January 1, 1978
Creator: Lohrding, R. K.; Johnson, M. M. & Whiteman, D. E.
System: The UNT Digital Library
Simulation experiments and solar wind sputtering (open access)

Simulation experiments and solar wind sputtering

In order to isolate the role played by solar wind sputtering from other lunar surface phenomena a number of simulation experiments were performed, including isotope abundance measurements of Ca sputtered from terrestrial fluorite and plagioclase by 50-keV and 130-keV /sup 14/N beams, measurement of the energy distribution of U atoms sputtered with 80-keV /sup 40/Ar, and measurement of the fraction of sputtered U atoms which stick on the surfaces used to collect these atoms. 10 references. (JFP)
Date: January 1, 1978
Creator: Griffith, J. E.; Papanastassiou, D. A.; Russell, W. A.; Tombrello, T. A. & Weller, R. A.
System: The UNT Digital Library
Distinction between the roles of O/sub 2/ and of O/sup -//sub 2/ in biological radiodamage (open access)

Distinction between the roles of O/sub 2/ and of O/sup -//sub 2/ in biological radiodamage

The paper attempts to elucidate the roles of oxygen and superoxide radical in biological damage due to ionizing radiation. Specifically, the effect of gamma radiation on the survival of T4 bacteriophage and of E. coli B has been investigated. (ACR)
Date: January 1, 1978
Creator: Samuni, A.; Chevion, M.; Halpern, Y. S.; Ilan, Y. A. & Czapski, G.
System: The UNT Digital Library
Solar opacity and equation of state (open access)

Solar opacity and equation of state

The disadvantages of radiative diffusion over radiative transfer in the photosphere as used in structure calculations is reemphasized. Uncertainties in the opacity due to uncertainties in chemical composition and in approximations of the physics are described and estimated. Internal consistency of equation of state and opacity is recommended.
Date: January 1, 1978
Creator: Huebner, W.F.
System: The UNT Digital Library
Excision repair in mammalian cells. [uv radiation, N-acetoxy-2-acetylaminofluorene] (open access)

Excision repair in mammalian cells. [uv radiation, N-acetoxy-2-acetylaminofluorene]

Excision repair after combined treatments of uv and N-acetoxy-2-acetylaminofluorene (AAAF) was studied by three different techniques in cells proficient in uv excision repair and in cells deficient in uv repair. Two patterns of repair were observed: in repair proficient cells total repair was additive, and in repair deficient cells total repair was much less than additive--usually less than observed for separate treatments--and AAAF inhibited dimer excision. We conclude that in the 1st class of cells pathways for repair of uv and AAAF lesions are not identical, and in the 2nd class the residual excision enzymes are different from those in repair proficient cells.
Date: January 1, 1978
Creator: Ahmed, F.E. & Setlow, R.B.
System: The UNT Digital Library