This index to Nuclear Safety covers articles published in Nuclear Safety, Vol. 11, No. 1 (January-February 1970), through Vol. 18, No. 6 (November-December 1977). It is divided into three sections: a chronological list of articles (including abstracts) followed by a permuted-title (KWIC) index and an author index. Nuclear Safety, a bimonthly technical progress review prepared by the Nuclear Safety Information Center (NSIC), covers all safety aspects of nuclear power reactors and associated facilities. Over 450 technical articles published in Nuclear Safety in the last eight years are listed in this index.

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Inclusive distribution for lepton pair production was studied in QCD in an improved leading logarithms approximation that allows for large angle gluon correction. A formula is derived for arbitrary values of the dilepton transverse momentum. It does not factorize into the generalized Drell--Yan form. 10 references.

The fusion-fission hybrid is a combination of the fusion and fission processes, having features which are complementary. Fission energy is running out of readily available fuel, and fusion has extra neutrons which can be used to breed that fission fuel. Fusion would have to take on an extra burden of radioactivity, but this early application would give fusion, which does not work well enough now to make power, practical experience which may accelerate development of pure fusion.

A number of topics in nonlinear and linear instability theory are covered in this report. The nonlinear saturation of the dissipative trapped electron instability is evaluated and its amplitude compares well with existing experimental observations. The nonlinear saturation of the drift cyclotron loss-cone mode is carried out for a variety of empty loss-cone distributions. The saturation amplitude is predicted to be small and stable. An improved linear theory of the collisionless drift instability in sheared magnetic fields yields the surprising result that no instability occurs for a wide range of parameters. Finally, the bump-on-tail calculation is shown to be unchanged by some recent results of Case and Siewart, and a rough time scale is established for the transition from the O'Neil trapping regime to the final time-asymptotic result.

An account is given of the obervations of the pitch angle distributions of energetic particles in the near equatorial regions of the Earth's magnetosphere. The emphasis is on relating the observed distributions to the field configuration responsible for the observed effects. The observed effects relate to drift-shell splitting, to the breakdown of adiabatic guiding center motion in regions of sharp field curvature relative to partial gyro radii, to wave-particle interactions, and to moving field configurations. 39 references.

In response to the increasing severity of target surface finish requirements for laser fusion experiments, it has become necessary to examine spherical targets in the Scanning Electron Microscope prior to laser irradiation on an orderly nondestructive basis. A new sample manipulation technique has been developed which rolls a thin wall sphere through 4..pi.. steradians without damage and allows easy recovery by placing the sphere between two parallel plane surfaces formed in silicone rubber on the ends of two 0.9 mm capillaries. Mechanical slides, actuated by normal stage controls, cause the capillaries in contact with the sphere to translate laterally and roll the ball. Using theta Z and theta Y motions, the entire surface of the sphere can be brought into a position for examination. With the capillaries oriented for best secondary electron collection and conductively coated, resolutions comparable with traditional mounting techniques are attained. A side looking tilted crystal Si(Li) detector has been incorporated to increase the utility of the system and allow simultaneous EDX microanalysis.

In a recent study of the convergence properties of finite element methods in nonlinear fluid mechanics, an indirect approach was taken. A two-dimensional example with a known exact solution was chosen as the vehicle for the study, and various mesh refinements were tested in an attempt to extract information on the effect of the local Reynolds number. However, more direct approaches are usually preferred. In this study one such direct approach is followed, based upon the spectral decomposition of the solution operator. Spectral decomposition is widely employed as a solution technique for linear structural dynamics problems and can be applied readily to linear, transient heat transfer analysis; in this case, the extension to nonlinear problems is of interest. It was shown previously that spectral techniques were applicable to stiff systems of rate equations, while recent studies of geometrically and materially nonlinear structural dynamics have demonstrated the increased information content of the numerical results. The use of spectral decomposition in nonlinear problems of heat and mass transfer would be expected to yield equally increased flow of information to the analyst, and this information could include a quantitative comparison of various solution strategies, meshes, and element hierarchies.

Two types of direct converters, one for beams and one for plasma, are under development with voltages and power densities approaching reactor-like conditions. Beam direct conversion raises the efficiency of producing neutral beams, can save millions of dollars when applied to next-generation experiments, and can improve the power balance of driven reactors. Direct conversion allows positive ion beams to be made into neutrals efficiently up to 150 keV for D/sup 0/, 225 keV for T/sup 0/ and 300 keV for /sup 3/He/sup 0/. Above these energies, the efficiency is less than 50% and falling rapidly, requiring negative ions to be used for neutral beam formation, which even they can benefit from direct conversion because the conversion fraction from negatives to neutrals is less than 100% (approximately 80% plasma cell, approximately 60% gas cell). The in-line beam direct conversion concept uses either electrostatic or magnetic fields for electron suppression. At low powers (approximately 1 kW continuous) and low voltage (10 to 15 keV), both have operated at an efficiency better than 70%.

Reduced instrument responses are presented for Thermal-Hydraulic Test Facility (THTF) test 168R, which is part of the ORNL Pressurized-Water Reactor (PWR) Blowdown Heat Transfer Separate-Effects Program. The objective of the program is to investigate the thermal-hydraulic phenomenon governing the energy transfer and transport processes that occur during a loss-of-coolant accident in a PWR system. Test 168R was conducted to obtain thermal-hydraulic and CHF information in the THTF bundle 1 to compare with tests having intact legs (166S and 167R). The primary purpose of this report is to make the reduced instrument responses during test 168R available. The responses are presented in graphical form in engineering units and have been analyzed only to the extent necessary to assure reasonableness and consistency.

It can cautiously be stated that there is not an imminent U.S. uranium crunch, because the installed capacity of fission reactors to 1990 is less than was anticipated. We have time for careful judgment and deliberation. We probably have until at least the year 2000 before beginning the phasing-in of a new technology to augment or replace the light water reactor. Consequently the fusion-fission hybrid appears to have strong potential as a fuel factory supplying fuel to the LWR industry. The hybrid relaxes some of the physics and engineering constraints on pure fusion and should be available somewhat sooner. The hybrid also integrates into the energy plan by supporting fission rather than replacing it. The hybrid seems like a good interface between the eventual pure fusion reactor and fission. The easing of the fission fuel demand under that which was anticipated, coupled with the high probability that available uranium resources are proportional to the price paid per pound (within limits) are likely, more than currently stated, serving to fusion's advantage by buying time for development.

The purpose of this research program is the demonstration of the technical feasibility of a high-temperature, solid-electrolyte fuel cell, building on the presently-existing technological base. The bulk of the work consists of identifying and selecting candidate component materials, fabricating cells and cell stacks from these materials, and testing these cells and cell stacks under conditions which might be expected in operation. The major emphasis is on the invention and fabrication of an interconnection film. Emphasis is also being placed on the fabrication of porous support tubes of calcia-stabilized zirconia, to the desired specifications of tensile strength, porosity, surface finish, and purity. Concurrently, tubes will be prepared in-house and, if necessary, will also be purchased from commercial suppliers and evaluated for compliance. The overall technical effort is aimed at achieving 5 milestones in the 2 year period of the contract. These include: (1) identifying and selecting new candidate interconnection materials; (2) preparing porous support tubes to desired specifications; (3) demonstrating acceptable test performance in identified interconnection material(s) and (5) in cell stacks. Progress is reported. (WHK)

The Weibull distribution arises as an example of the theory of extreme events. It is commonly used to fit statistical data arising in the failure analysis of electrical components and in DC breakdown of materials. This distribution is employed to analyze time-to-damage and intensity-to-damage statistics obtained when irradiating thin film coated samples of SiO/sub 2/, ZrO/sub 2/, and Al/sub 2/O/sub 3/ with tightly focused laser beams. The data used is furnished by Milam. The fit to the data is excellent; and least squared correlation coefficients greater than 0.9 are often obtained.

This term Q is the ratio of the fusion powder produced to the power input. It is a driven device. Q is truly the success parameter for mirrors--widely discussed but not succinctly specified as to required value. The problem is that Q can be treated as a subjective parameter--there are many milestone Qs; for scientific demonstration, for breakeven power, etc. Yet for a successful reactor, there is only one Q and that is the Q which produces mirror fusion power at the busbar that is less than the cost of delivered power in mills/kwhr by other means. We call this Q/sub PRACTICAL/ and believe there is a convincing argument that says this Q/sub PRACTICAL/ can be about 5.0 even assuming modest efficiencies for system components. A direct convertor is necessary. If the direct convertor were deleted, a Q/sub PRACTICAL/ of approximately 7.5 would be required. If we wish to soften the value of Q further, then the technical logic for the fusion fission hybrid is very powerful. With the hybrid a Q/sub PRACTICAL/ of 1.5 to 2.0 appears to be a very reasonable value. The key in being able to specify values of Q/sub PRACTICAL/ lies in economically comparing the …

Site suitability studies have been made previously at LLL on bedded salt and shale. In the present study domed salt, basalt, and crystalline rock are compared with bedded salt and shale and with each other as possible repositories. The level of effort required to develop models for these media that are similar in quality to those available for bedded salt and shale is evaluated. The effort necessary to develop data bases on the physical and chemical properties comparable to that available for bedded salt and shale is also estimated. Each medium is evaluated as a suitable repository environment. The funding necessary for model and data base development is estimated. (JSR)

Microstructural analysis of sessile drop experiments of silicon on mullite indicate reaction at the liquid solid interface which is especially severe after ten hours. Compositional variation including higher purity and elimination of the glass phase did not affect the reaction. The increased surface area of porous samples caused severe structural damage to these substrates. Reaction phases are found away from the interface after long exposure. Compositional variations have been found to lower the thermal expansion of the mullite to the expansion of silicon. The addition of silica to a standard mullite body is found to increase the amount of glass phase while lowering expansion. It has also been found that a mixture of fused mullite and fused silica fires to a body with thermal expansion very near that of silicon. The thermal expansion of silicon was measured in the 111 crystal direction and found to concur with published data.

The phase velocity of a microwave signal propagating in a plasma is increased providing that its frequency is much higher than the plasma frequency. It follows that by forming a resonator around the plasma and noting the resonant frequency shift plasma frequency and thus plasma density may be measured. To check the feasibility of this type of measurement, a section of vacuum pipe in the HIF beam transport line was resonated and the frequency shift resulting when beam was turned on was noted.

The document has been prepared pursuant to the second meeting of the Senior Research Review Group of the Seismic Safety Margin Research Program (SSMRP), which was held on June 15, 16, 1978. The major portion of the material contained in the document is descriptions of specific subtasks to be performed on the SSMRP. This is preceded by a brief discussion of the objective of the SSMRP and the approach to be used. Specific subtasks to be performed in Phase I of the SSMRP are as follows: (1) plant/site selection, (2) seismic input, (3) soil structure interaction, (4) structural building response, (5) structural sub-system response, (6) fragility, (7) system analysis, and (8) Phase II task definition.

Progress in developing mathematical models to describe combustion conditions with and without swirl in automotive engine combustion chambers and calculations performed with these models are discussed. (LCL)

The Magnetic Mirror Fusion Program is one of the two main-line fusion efforts in the United States. Starting from the simple axisymmetric mirror concept in the 1950's, the program has successfully overcome gross flute-type instabilities (using minimum-B magnetic fields), and the most serious of the micro-instabilities which plagued it (the drift-cyclotron loss-cone mode). Dense plasmas approaching the temperature range of interest for fusion have been created (n/sub p/ = 10/sup 14//cc at 10 to 12 keV). At the same time, rather extensive conceptual design studies of possible mirror configurations have led to three principle designs of interest: the standard mirror fission-fusion hybrid, tandem mirror, and the field-reversed mirror. The lectures will discuss these three concepts in turn. There will be no discussion of diagnostics for the mirror machine in these lectures, but typical plasma parameters will be given for each type of machine, and the diagnostic requirements will be apparent. In a working fusion reactor, diagnostics will be required for operational control, and remarks will be made on this subject.

The overall purpose of this two-stage program is the demonstration of continuous Czochralski growth. In Stage 1, an existing Varian 2850 Czochralski furnace is to be modified for continuous growth by recharging; in Stage 2, a new puller is to be designed and shown capable of producing 100 kg of crystal from the same crucible with an after-grind yield of at least 70%. The three components required to modify the Varian furnace for batch and continuous recharging with granular silicon have been designed and are currently being fabricated. The feasibility of extended growth cycles up to 40 hours long has been demonstrated by a recharge simulation experiment; a 6 inch diameter crystal was pulled from a 20 kg charge, remelted, and pulled again for a total of four growth cycles, 59/sup 1///sub 8/ inch of body length, and approx.65 kg of calculated mass. A preliminary economic analysis indicates that the 1982 SAMICS price goal allocation can be met by sheet production predicated upon the recharging of otherwise standard Czochralski furnaces; the projections are, in 1975 dollars: add-on cost for growth--$37 per m/sup 2/, direct poly cost--$46 per m/sup 2/, margin available for wafering--$45 per m/sup 2/.

The basic set of equations is derived for the calculation of the time-dependent electrical conductivity of an initially unionized gas generated by a propagating relativistic electron beam. In contrast with previous work, which used thermal averages, conductivity is determined from the complete, nonequilibrium electron energy distribution. The evolution of the distribution function, resulting from interaction with gas molecules, ions, beam induced electric field, and beam current, is described by a Boltzmann equation.

In most past studies of the effectiveness of tactical nuclear weapons vs the amount of collateral damage produced (civilian casualties), civilians have been congregated into idealized shaped towns and cities, and criteria for city avoidance were usually formulated in terms relating to a town's population. This treatment was sufficient in those studies where weapon yields were so large that great numbers of civilians were almost always placed at risk. As further studies developed, demonstrating that real progress could be made in reducing the numbers of civilians potentially placed at risk in tactical nuclear warfare situations, the inadequacies of the present treatment became obvious. The need existed for a more detailed description of the distribution of civilians. The method described determines the number of civilians at risk for a weapon under consideration being detonated at a given point and displays a symbol relating to the numbers at risk on a map or a transparency that overlays a 1:50,000 map of the region. Thus, a weapons planner making the selection of aimpoints for inflicting the necessary military damage required has the means to reduce potential civilian casualties by properly choosing the weapon and aimpoints.