A model for a windowed, high-temperature cavity receiver of the heated-air type is developed and used to evaluate the greenhouse effect as a method for obtaining high receiver operating efficiencies. The effects on receiver efficiency of varying the window cutoff wavelength, the amount of absorption in the window pass-band, the cavity operating temperature, and the number of windows are determined. Single windowed cavities are found to offer theoretical efficiencies comparable to windowless ones, while multiple windowed units are found to suffer from low operating efficiencies due to losses resulting from reflections at each window/air interface. A ''first order'' examination is made of the feasibility of air cooling the window to assure its survival. This appears possible if a proper combination of cooling technique and window material characteristics is selected.

Numerical codes have been developed for the description of the nonlinear evolution of tearing modes in tokamaks. The m = 1 mode is observed to continue rapid growth in the nonlinear regime, producing significant changes on a time scale consistent with the experimentally observed minor disruption. The double tearing mode associated with a hollow current profile also continues rapid growth in the nonlinear regime, and thus may play a significant role in the anomalous current penetration during the early stages of a tokamak discharge. Single magnetic islands with m greater than or equal to 2, on the other hand, cease exponential growth upon entering the nonlinear regime and saturate shortly thereafter. A model for the saturation processes is presented. Modifications due to thermal transport are discussed.

A system model of the mirror hybrid reactor has been developed. The major components of the model include (1) the reactor description, (2) a capital cost analysis, (3) various fuel management schemes, and (4) an economic analysis that includes the hybrid plus its associated fission burner reactors. The results presented describe the optimization of the mirror hybrid reactor, the objective being to minimize the cost of electricity from the hybrid fission-burner reactor complex. We have examined hybrid reactors with two types of blankets, one containing natural uranium, the other thorium. The major difference between the two optimized reactors is that the uranium hybrid is a significant net electrical power producer, whereas the thorium hybrid just about breaks even on electrical power. Our projected costs for fissile fuel production are approximately 50 $/g for /sup 239/Pu and approximately 125 $/g for /sup 233/U.

Advances in electrochemical engineering are reviewed and the methodology of analysis of electrochemical systems outlined. Examples illustrative of current research concern simultaneous reactions for flow-through porous electrodes and the more fundamental system of a rotating-disk electrode. Here the undesirable side reaction is the formation of dissolved hydrogen, and the main reaction is the deposition of copper from sulfuric acid solutions. Distributions of reaction rate, concentration, and potential describe the detailed system behavior. The side reaction is responsible for the poorly defined limiting-current plateau on the disk electrode and provides a limit for the maximum flow rate at which good recovery can be achieved with the porous electrode. 16 figures.

The fuel temperature attained in laser initiated fusion of DT filled targets is determined from the line width of the neutron energy spectrum. Spectral measurements are made using a 45-meter neutron time-of-flight spectrometer at the ARGUS laser irradiation facility. The large fluor-photomultiplier package used as the neutron detector has a 4.5 nsec FWHM response to a burst of neutrons and a 3.5 nsec response to a single neutron event. Appropriate unfolding of the measured data enables us to determine line widths above 100 keV with a resolution of 40 keV or equivalently, plasma temperatures of approximately 1 keV and above.

An extensive data acquisition and analysis system has been implemented for experiments on the ARGUS laser. The system is based upon a PDP-11/40 minicomputer and CAMAC interfaces. Highspeed transient digitizers, calorimeter digitizing modules and time integrated data are interfaced through CAMAC over a fiber optic serial highway. The system allows for dynamic definition of the experimental environment by an operator, automatic data acquisition during a shot. Two interactive graphics terminals allow experimenters real-time access to target shot data.

The neutronic study of the conceptual laser fusion hybrid reactor designed by the Lawrence Livermore Laboratory in collaboration with the Bechtel Corporation is discussed. The operational parameters of the reactor, i.e., energy multiplication, power density, burnup, and plutonium production, have been investigated for three fuel materials; low alloy uranium metal in its natural and depleted form, uranium carbide and uranium with 7 percent by weight molybdenum alloy. Uranium metal shows the highest energy multiplication and fissile fuel production. The neutronic calculations have been done using the Monte Carlo Neutron Transport code TART for two neutron libraries, the ENDF/B-IV and the ENDL with no significant differences in the results. Spatial and time distributions of the operational parameters have been calculated based on a first-wall loading of 1 MW/m/sup 2/.

The energy carried by particles and low energy x-rays resulting from irradiation of targets with .5 to 1 TW, 1.06 ..mu..m lasers has been measured. The energy distributions were obtained from measurements at discrete locations using calorimeters and work is in progress to obtain them over a hemisphere with a thermal imaging system. Azimuthal symmetry and polar distributions for different focusing schemes have been determined. The data have been integrated to obtain the absorbed energy and these values compared to box calorimetry and optical energy balance. The relative emission of low energy x-rays from different Z materials can be obtained by comparing these data to charge collector data. Such comparisons also showed that the effective ion charge can be as low as a factor of two below the completely ionized state. The existence of low charge state ions has since been confirmed with high resolutions spectrometers.

The ion source, acceleration tube, and beam transport system for the Lawrence Livermore Laboratory (LLL) T(d,n) /sup 3/He neutron sources are described. To produce 4 x 10/sup 13/ n/s, a 150-mA D/sup +/ beam at 400 keV is required. A 17-aperture version of the reflex-arc MATS-III ion source is under test for this use. To simplify the acceleration tube and beam transport design, a 90/sup 0/ double-focusing magnet is to be used to separate the D/sup +/ component from molecular beam components. Emittance measurements on the resulting D/sup +/ beam are given. A four-gap, uniform-field acceleration column was designed. Beam trajectory calculations for the acceleration column and transport system are presented. Design concepts will be tested on a prototype accelerator scheduled to operate in mid-1977.

The cross section for the generation of helium in neutron irradiated carbon was found to be 654 mb at 14.4 MeV and 744 mb at 14.9 MeV. Extrapolating to 14.1 MeV (the fusion reactor spectrum) gives 615 mb. The diffusion of helium in dense polycrystalline graphite and in pyrographite was measured and found to be D = 7.2 x 10/sup -7/ m/sup 2/s/sup -1/ exp (-80 kJ/RT). It is assumed that diffusion is primarily in the basal plane direction in crystals of the graphite. In polycrystalline graphite the path length is a factor of ..sqrt..2 longer than the measured distance due to the random orientation mismatch between successive grains. Isochronal anneals (measured helium release as the specimen is steadily heated) were run and maximum release rates were found at 200/sup 0/C in polycrystalline graphite, 1000/sup 0/C in pyrographite, 1350/sup 0/C in boron carbide, and 1350/sup 0/ and 2400/sup 0/C (two peaks) in silicon carbide. It is concluded that in these candidates for curtain materials in fusion reactors the helium releases can probably occur without bubble formation in graphites, may occur in boron carbide, but will probably cause bubble formation in silicon carbide. 7 figures.

Much of the target diagnostics data from the ARGUS laser are acquired through a CAMAC interface system, including equipment on a CAMAC serial highway. A scheme has been developed which allows a very general capability for dynamically defining the experimental configuration such that the serial highway is invisible to the controlling program. High level language software compiles the existence of each experimental entity in the system. As the position and description of each module is defined, a software structure is built, with each entry containing the information to be provided to the CAMAC handlers during operation of the equipment. Provision is made to allow tight loops at the lowest software level for critical high speed data acquisition. Currently, the serial highway is operated at a one megabit rate, allowing 24 bit CAMAC words to be transferred at a 5 KHz rate.

The SHIVA laser is a 20 beam Nd-doped glass laser designed to provide various irradiation geometries for fusion pellets. The general objective of the SHIVA laser is to achieve significant thermonuclear burn or about 1 percent of scientific breakeven by isentropic compression. Descriptions are given of the laser system, physical configuration, alignment system, and the computer control system. (MOW)

The temporal signature of kilovolt x-ray emission from laser compressed fusion targets has previously been described as displaying structure identifiable with distinct heating and compression phases. In this paper quantitative measures of this temporal structure are correlated with neutron yields and laser performance.

Very high single-step enrichment of deuterium, carbon-13, oxygen-17, and oxygen-18 has been achieved by photo-predissociation of formaldehyde with tunable near-ultraviolet ion lasers. Insertion of an intracavity etalon permitted tuning the XeIII 345.425nm ion laser transition over 10 GHz and the NeII transitions at 337.824nm and 332.375nm over 16 GHz to permit optimized isotopic selectivity of each formaldehyde isotope having absorption within the ion laser tuning range. Natural abundance deuterium was enriched 60-fold at 345nm to yield hydrogen gas with 1.6 percent HD, and 180-fold enrichment of deuterium as D/sub 2/ was achieved at 332nm. Substituting neon-22 blue-shifted laser emission 7 GHz to permit 33-fold enrichment of natural abundance carbon-13 to yield 29 percent /sup 13/CO photoproduct. D/sub 2/CO was used to achieve 44-fold oxygen-18 enrichment at 332nm and 27-fold oxygen-17 enrichment at 338nm also using the neon-22 ion laser. Radical production in D/sub 2/CO is less than 1 percent at 332nm. Isotope scrambling is 24 percent for C-13 using H/sub 2//sup 13/CO at 332nm, 4 percent for 0-18 using D/sub 2/C/sup 18/O at 332nm, and 9 percent for 0-17 using D/sub 2/C/sup 17/O at 338nm.

A more compact ..cap alpha..-particle time-of-flight spectrometer using a permanent field deflection magnet has been developed for laser fusion burn diagnostics. The spectrometer is being used to measure the number and energy distribution of fusion-produced ..cap alpha.. particles emitted from laser implosions of DT gas contained in glass microshells. It is planned to view the target from different angles using several spectrometers simultaneously. Comparison of energy loss and energy broadening vs angle can yield information concerning the nature of compression and subsequent burn. Results from target experiments on the LLL ARGUS laser facility are present.

Tokamak plasmas fueled and heated by energetic neutral-atom beams are characterized by total ion pressure greatly exceeding the electron pressure. For smaller devices with relatively low injection energy, the largest fusion reactivity of energetic-ion plasmas is obtained when oppositely injected D/sup 0/ and T/sup 0/ beams sustain large densities of counterstreaming deuterons and tritons (CIT mode). In this study steady-state ion velocity distributions for the CIT are calculated with a multi-species Fokker-Planck code, and are found to have sufficient thermal spread so that all infinite-medium velocity-space modes are stable. Quasi-stationary operation seems physically realizable, because the injected beams provide all fueling, and the counterstreaming ions can be made to carry the bulk of the plasma current required for equilibrium; a satisfactory magnetic flux-surface configuration is revealed by a particle simulation code. Steady-state radial profiles of plasma parameters are determined with a coupled Fokker-Planck/radial transport code that includes charge-exchange effects and particle and heat diffusion of ''warm'' ions and electrons. With inclusion of realistic charge-exchange loss and a significant warm-ion population, the ideal CIT Q-values are found to be reduced by 60 to 70 percent for a given (n/sub e/tau/sub Ee/). For example, Q = 1.0 for W/sub inj/ = 80 …

There are four known geothermal resource areas in the Imperial Valley that have a combined potential of over 4,000 megawatts of electrical energy for 25 years. The water resources available to support geothermal energy development are imported Colorado River water, agricultural waste waters, Salton Sea water, and ground water. In addition, geothermal power plants can produce their own cooling water in the form of steam condensate. Nevertheless, the relatively high water requirements of geothermal facilities along with a series of real and potential constraints may cause water supply dilemmas involving both the acquisition and use of cooling water. Important constraints are institutional policies, water supply costs, technical problems, and impacts upon the Salton Sea. These constraints and related dilemmas are examined in light of relevant information on the valley's water resources, geothermal resources and energy technologies, cooling water requirements, and water supply options.

The preliminary design of an accelerator suitable to meet the flux and neutron energy requirements of a CTR materials test facility is presented. The specifications of such a facility call for a neutron flux of 10/sup 14/ n/cm/sup 2/-sec distributed over an area of about 10/sup 2/cm/sup 2/ with a neutron spectrum similar to that anticipated from a fusion reactor. A 30 MeV deuteron linac producing a CW beam of 125 mA, upgradable to 40 Mev at 250 mA at a later date, would produce the relatively broad spectrum of neutrons at the required intensity. Beam dynamics at the required current dictate an injection energy of 750 keV and a frequency of 50 MHz. The average axial field of 1 MV/m results in a wall power density of slightly less than the Super-HILAC at full gradient and 30% duty factor. Each of the seven cavities will have its own 800 kW rf power source for a 125 mA beam intensity, expandable to 250 mA by doubling the number of rf sources. Attention to the low-energy beam intercept on the drift tubes and diffusive losses producing neutrons and attendant activation problems are discussed.

MODEL/LINDA/GRAPEL is a unified logic design automation system consisting of a synthesis program (LINDA), a simulation program (MODEL), and a documentation program (GRAPEL). The base hardware description language is briefly covered. Extensibility features to nonhardware aspects of digital systems designs are discussed. The algorithms of GRAPEL, (Graph for Engineering Language), particularly the device placement and inter-connect routing strategies, are explained. Several examples and applications are offered. 6 figures, 3 tables.

The early stage deformation behavior of Ti-50.3 at. percent Ni alloy was investigated. It was found that stress induced twin-boundary migration within existing martensite variants, migration of twin boundaries between twin-related adjacent martensite variants, reorientation of existing martensite by twinning on the most favorably oriented twin system, and additional transformation at the expense of retained high temperature phase.

The feasibility of using ammonia as an intermediate heat exchange fluid, i.e. between the power plant and the dry cooling tower was studied. Information is included on the advantages and disadvantages of using ammonia, design criteria for such a dry cooling system, and a comparative cost projection for the components and overall system. The results showed that the ammonia heat exchange system could save half the cost of transporting the coolant as compared with a conventional indirect cooled dry system, that the heat exchanger cost would be 20 percent less, and the tower would be smaller and cheaper. The condenser/reboiler would be more expensive. Overall a 25 percent saving in total system capital cost and $500 K/yr. in operating costs are projected as compared with wet/dry deluge system of identical capability. Also there are no freezing problems with the ammonia system. It is recommended that: a demonstration unit be designed; performance testing on components be undertaken; a design optimization code for dry/wet systems be developed; and that a test loop be constructed and operated. (LCL)

A versatile and highly adaptable computer controlled x-ray diffraction system, capable of multi-sample unattended operation, is described. This system, operated from a terminal at the instrument site on a 24 hour-per-day basis, is a tool currently in use for both routine sample analysis and research purposes. Interfacing between the computer and the instrument was accomplished through CAMAC, an internationally standardized, nonproprietary modular technique. System controlling software was developed by Atlantic Richfield Hanford Company personnel and was written in FORTRAN. The diffraction system is discussed from the aspects of hardware (the instrument, CAMAC, and the computer) and from software, (system considerations, data acquisition, instrument control, and data reduction). User control and adaptability are emphasized as the prime advantages of the system. Planned future enhancements are briefly described to illustrate these advantages.

In recent years there has been growing discussion over the ability of new siting approaches to redress the increasing problems of nuclear plant location. This debate has focused largely on three alternatives to the conventional siting of nuclear reactors; floating offshore plants; underground siting; and nuclear energy centers (NECs) consisting of up to 40 reactors at a single site, and, possibly, including fuel cycle facilities within their perimeter. Congressional interest in energy centers, especially in view of concern over the proliferation of nuclear reactors throughout the country, and with the special problems of safeguards over fuel reprocessing and the use of plutonium as a reactor fuel, resulted in a mandate to the Nuclear Regulatory Commission to make a comprehensive analysis of the energy center concept. A common finding of all of the studies of the nuclear energy center concept thus far is that there appear to be no technical considerations that would clearly preclude energy centers. With the one significant exception regarding the meteorological impacts of the concentration of heat and moisture releases to the atmosphere, engineering solutions would appear to be quite adequate to address any difficulties of environmental impact, electrical systems management, water supply or construction management, and …

The design of a first wall for a 20 MW thermonuclear power laser fusion hybrid reactor is presented. The 20 mm thick graphite first wall is located 3.5 m from the DT microexplosion with a thermonuclear yield of 10 MJ. Estimates of the energy deposition, temperature, stresses, and material vaporized from the first wall due to the interaction of the x-rays, charged particle debris, and reflected laser light with the graphite are presented, along with a brief description of the analytical methods used for these estimations. Graphite is a viable first wall material for inertially-confined fusion reactors, with lifetimes of a year possible.