The neutral-beam injection systems for the next generation of U. S. fusion experiments (TFTR, MX, Doublet III) have requirements that considerably exceed the present state of development. TFTR, for example, desires 20 MW of 120-keV deuterium atoms in pulses of 0.5-sec duration. The neutral-beam systems needed to meet these demands will be large and complex and will require much development effort. In order to develop components for these new systems, a new, large test facility was constructed. The vacuum system, which has a volume in excess of 170,000 liters, will handle the pulsed gas loads by volume expansion; the gas will be pumped out in the one-minute intervals between pulses. The power-supply philosophy and specification are discussed in an accompanying paper. A mini-computer system will be used to monitor and control the power supplies and to diagnose the beam. Of the beam-line components, a plasma source and 120-kV accelerator structure which are under construction are discussed. A new long-pulse version of our 15-cm-diam high-current plasma source has been developed. Significant improvements have been made by re-orienting the filaments, so that they produce closed magnetic field lines near the wall, and by changing the shape and position of the anode. This …

Differential cross sections for the reaction /sup 3/H(d,n)/sup 4/He have been measured at 7.00 and 10.00 MeV using the time-of-flight technique. By measuring both /sup 3/H(d,n)/sup 4/He and /sup 2/H(t,n)/sup 4/He at the same center of mass, energy-complete distributions between 0/sup 0/ and 180/sup 0/ have been obtained. The absolute scales have been established within +- 1.5 percent by using the accurate /sup 2/H(t,/sup 4/He)n cross sections at 20.0 MeV as a standard.

The objective of this study was to determine acceleration levels experienced by the ERDA thermal converter unit implanted abdominally in a calf. A full-scale weighted mock-up of the thermal converter was fabricated containing a triaxial accelerometer. The mock-up was implanted in calf cadavers which were subjected to falls from an operating table. Highest acceleration recorded was 34 g. The mock-up was implanted in living animals and acceleration measurements made under various maneuvers including walking, standing from a laying position, walking up and down stairs, jumping, and falling from a standing position. Maximum acceleration recorded was 8 g and occurred in the falling maneuver.

The analyses of four transients imposed on a Gas Cooled Fast Breeder Reactor (GCFBR) plant are presented. These calculations were carried out using the HELAP code, which is based on RELAP 3B. The transient imposed on the system is a design basis depressurization accident (DBDA) with no scram. Furthermore, the rupture size causing the depressurization was varied over a range from .6 ft/sup 2/ to zero. In the limit of no rupture the transient imposed on the system is due only to the transient behavior of the steam generator and circulator turbine during a DBDA. The following observations can be made, based on this work: (1) The time to clad failure as determined in this work is much shorter than in the previously published preliminary work. (2) In the case of no rupture, the agreement between the current analysis and the previously carried out analysis is better. (3) In the case of smaller rupture sizes the superheater tube wall is subject to rapidly rising temperatures and pressures. The latter rise would be strongly affected by the capacity of the safety and relief valves. These temperatures and pressure transients should be evaluated with the tube wall strength in mind, since a …

Separate abstracts were prepared for each of the six sections on analytical research and development. Service analyses, activities related to education, supplementary professional activities, and means of presentation of research results are also discussed. (JGB)

The work done, primarily in various aspects of U and Pu determinations, was reported in individual reports on each project. Separate abstracts were prepared. (JSR)

Plutonium alloy foils, thin enough for transmission electron microscopy (TEM), were made by rapidly quenching small specimens from the melt in a ''gun''-type, splat-cooling device. Microstructures in selected regions of the nonequilibrium alloys thus produced are illustrated and discussed. (auth)

The distribution of /sup 210/Pb and /sup 210/Po in dissolved (less than 0.4 micron) and particulate (greater than 0.4 micron) phases was measured at ten stations in the tropical and eastern North Atlantic and at two stations in the Pacific. Both radionuclides occur principally in the dissolved phase. Unsupported /sup 210/Pb activities, maintained by flux from the atmosphere, were present in the surface mixed layer and penetrated into the thermocline to depths of about 500 m. Dissolved /sup 210/Po was ordinarily present in the mixed layer at less than equilibrium concentrations, suggesting rapid biological removal of this nuclide. Particulate matter was enriched in /sup 210/Po, with /sup 210/Po//sup 210/Pb activity ratios greater than 1.0, similar to those reported for phytoplankton. Box-model calculations yield a 2-y residence time for /sup 210/Pb and a 0.6-y residence time for /sup 210/Po in the mixed layer. These residence times are considerably longer than the time calculated for turnover of particles in the mixed layer (about 0.1 y). At depths of 100 to 300 m, /sup 210/Po maxima occurred and unsupported /sup 210/Po was frequently present. Calculations indicate that at least 50 percent of the /sup 210/Po removed from the mixed layer is re-cycled within …

A review of current programs to develop superconducting power transmission shows that current plans require helium refrigerators operating at 5 to 13/sup 0/K and 3 to 15 atm pressure with compressor power input in the range of 1,300 to 3,500 HP. Future requirements will probably trend toward slightly higher temperatures and larger refrigerators. Present large helium refrigerators and APCI standard nitrogen plants were studied and an average outage frequency of about 18 per year is found to be typical for both. Cost and reliability studies of alternate refrigeration systems based on studies of components shows that the best current system which would have a failure rate of once in 20 years would consist of two full size oil flooded screw compressors in parallel, manifolded to two full size cold boxes and a liquid helium back up dewar. The principal area of development needed to implement this system is in the switch over mechanisms. These include switching to an auxillary power source in the event of power interruption, switching to the standby compressor, and switching to the back up liquid helium dewar. Costs are projected as being only slightly greater than preliminary estimates.

Fusion as a power source is receiving an increasing amount of attention. Several designs have been proposed and the feasibility of each alternative is being studied. As we move closer to a working design, attention can be paid to potential biological hazards. Large magnetic fields and the emission of tritium and lithium are unique to some fusion reactor designs. The results of a review of the current state of knowledge concerning the biological effects of magnetic fields alone and in combination with ionizing radiation are summarized in this report. The purpose of the review is to help identify areas where additional biomedical research is needed for establishing guidelines for reactor design and operation. 64 references (auth)

A computer program is described which calculates nuclide concentration histories, power or neutron flux histories, burnups, and fission-product birthrates for fueled experimental capsules subjected to neutron irradiations. Seventeen heavy nuclides in the chain from $sup 232$Th to $sup 242$Pu and a user- specified number of fission products are treated. A fourth-order Runge-Kutta calculational method solves the differential equations for nuclide concentrations as a function of time. For a particular problem, a user-specified number of fuel regions may be treated. A fuel region is described by volume, length, and specific irradiation history. A number of initial fuel compositions may be specified for each fuel region. The irradiation history for each fuel region can be divided into time intervals, and a constant power density or a time-dependent neutron flux is specified for each time interval. Also, an independent cross- section set may be selected for each time interval in each irradiation history. The fission-product birthrates for the first composition of each fuel region are summed to give the total fission-product birthrates for the problem.

Ionization equilibrium calculations are carried out for iron ions at a density of 10/sup 12/ cm/sup -3/ in a (hydrogen) plasma with electron density 10/sup 14/ cm/sup -3/, at temperatures from 0.8 to 10 keV. The computed radiated power loss from this plasma due to the iron ions ranges from about 4 W/cm/sup 3/ at the lowest temperature to about 0.4 W/cm/sup 3/ at the highest temperature; loss rates for other electron and ion densities will scale approximately as N/sub e/N/sub Fe/10/sup 26/. The losses are due principally to collisionally excited line radiation (especially ..delta..n = 0 transitions) at low temperatures, and to collisionally excited ..delta..n not equal to 0 transitions and to continuum radiative recombination at high temperatures. Spectra are also computed for diagnostic x-ray K/sub ..cap alpha../ (1s - 2p) transitions; the change in spectral distribution as a function of temperature agrees well with observations in the ST Tokamak. Bound-bound radiative transitions and dielectronic recombination are discussed at length in appendices; the latter process is of great importance in the establishment of ionization equilibrium, and in the excitation of K/sub ..cap alpha../ radiation at the lower temperatures.

A formulation is developed to study reactor power capability based on the likelihood of incipient centerline fuel melting. Attention is also directed to the proper definition of this likelihood. As a consequence, it is shown how to compute the total probability for fuel melting as well as the expected number of fuel pellets and the associated variance. Factors considered include statistical variations in pellet fissile densities, gap sizes, coolant temperatures, reactor power, and the power-to-melt function. General formulas suitable for computation are given along with more transparent analytical results.

Displacement damage by 15 MeV (d-Be source) and fission neutrons at 30$sup 0$C in high purity niobium single crystals has been studied by transmission electron microscopy. The fluence of the 15 MeV neutrons was 1.5-- 2.0 x 10$sup 17$ n/cm$sup 2$ and the fluence of the fission neutrons (5 x 10$sup 17$ n/cm$sup 2$) was chosen so that samples from both types of irradiations had approximately the same damage energy. In both 15 MeV and fission neutron irradiated specimens, the loops were observed to be about $sup 2$/$sub 3$ interstitial and $sup 1$/$sub 3$ vacancy type. The analysis of Burgers vectors of the dislocation loops showed that more than $sup 2$/$sub 3$ of the loops were perfect a/2(111) and that the rest were a/2(110) faulted. It is concluded that at equal damage energies, the detailed nature of the damage is the same for 15 MeV and fission neutron irradiated niobium. (auth)

The actual coal gasification reaction is controlled diffusionally in the lower part of the bed and kinetically in the upper part of the bed. When closely size-graded pulverized coal particles undergo rapid devolatilization in a laminar flow reactor, the effect of heating-up time on weight loss is negligibly small. All other experimental conditions being equal, the smaller the particle, the greater is the weight loss. Reactivity of a char increases with increase in partial pressure of oxygen in the air-nitrogen mixtures. Reactivities of various chars are determined by rank of the parent coals and their mineral matter content. There is a 170-fold difference in the reactivities of various chars. Char reactivities are maximized by keeping the maximum heat treatment temperature as low as possible, the heating rate to maximum temperature as high as possible, and allowing no soak time at maximum temperature. Therefore, reactivity of a char prepared by rapid devolatilization is appreciably higher than that of a char prepared by heat treatment using slow heating rates. The differential scanning calorimetry technique can be used to characterize carbons in terms of their reactivities. Small angle x-radiation scattering shows promise in characterization of internal porosity in coal chars. Siderite and pyrite …

The occurrence and significance of complex characteristics in two-phase flow equation systems are clarified by a detailed analysis of separated two-phase flow between two parallel plates. The basic system of one-dimensional, two-phase flow equations for this problem possesses complex characteristics, exhibits unbounded instabilities in the short-wavelength limit, and constitutes an improperly posed initial value problem. These difficulties have led some workers to propose major modifications to the basic equation system. The relatively minor modification of introducing surface tension is shown to be sufficient to render the characteristics real, to stabilize short-wavelength disturbances, and to produce a properly posed problem. For a given value of the surface tension, the basic equation system thus modified is shown to predict correctly the evolution of small-amplitude disturbances having wavelengths long compared to the plate spacing. A formula is given for the artificial surface tension necessary to stabilize wavelengths of the order of the mesh spacing in a finite-difference numerical calculation. A brief discussion is given concerning the expected behavior of surface tension as compared to viscosity in the nonlinear regime. The general relationship between characteristics and stability is discussed in Appendix A.

We show that classical Sine-Gordon solitons maintain their integrity to a high degree in the presence of external perturbations. Two examples, of particular importance in condensed matter, are described in detail: (i) a model impurity is found to bind low-velocity solitons but merely phase-shift those with high-velocities, (ii) external static driving terms with damping accelerate the soliton to a terminal velocity. The importance of a translation mode is emphasized and it is concluded that the soliton behaves as a classical particle in all essential respects.

This report, the seventeenth of a series, is a compendium of monthly progress reports in support of the increased utilization of coal as a source of clean energy. The projects reported include those for hydrocarbonization, solid-liquid separations, chemical research and development, engineering evaluations of nuclear process heat for coal conversion, engineering evaluations of the hydrocarbonization and synthoil processes, and coal-fueled MIUS. Two more runs were completed with the bench-scale hydrocarbonization research system using nitrogen at 20 atm with the preheater at 1400/sup 0/F and the reactor at 1250/sup 0/F. Some difficulty was encountered with the coal feeder and corrective modifications are underway. Revisions and additions were made to the flowsheet for a plant using direct steam gasification of coal, which is thermally driven by a 3000-MW(t) VHTR. In the engineering evaluations work for the synthoil process, flow diagrams for four units were finalized. A preliminary facility site plan was developed. Conceptual design of the solids-liquid separation plant specifying centrifugation followed by filtration of the thickened underflow was completed. In the MIUS program, a /sup 1///sub 12/ scale model of the latest layout is being constructed. (auth)

The thermal, ecological, and social impacts of a 40-reactor NEC are compared to impacts from four 10-reactor NECs and ten 4-reactor power plants. The comparison was made for surrogate sites in western Tennessee. The surrogate site for the 40-reactor NEC is located on Kentucky Lake. A layout is postulated for ten clusters of four reactors each with 2.5-mile spacing between clusters. The plants use natural-draft cooling towers. A transmission system is proposed for delivering the power (48,000 MW) to five load centers. Comparable transmission systems are proposed for the 10-reactor NECs and the 4-reactor dispersed sites delivering power to the same load centers. (auth)

Dynamic compression wave studies have been conducted on Blair dolomite in the stress range of 0-7.0 GPa. Impact techniques were used to generate stress impulse input functions, and diffuse surface laser interferometry provided the dynamic instrumentation. Experimental particle velocity profiles obtained by this method were coupled with the conservation laws of mass and momentum to determine the stress-strain and stress-modulus constitutive properties of the material. Comparison between dynamic and quasistatic uniaxial stress-strain curves uncovered significant differences. Energy dissipated in a complete load and unload cycle differed by almost an order of magnitude and the longitudinal moduli differed by as much as a factor of two. Blair dolomite was observed to yield under dynamic loading at 2.5 GPa. Below 2.5 GPa the loading waves had a finite risetime and exhibited steady propagation. A finite linear viscoelastic constitutive model satisfactorily predicted the observed wave propagation. We speculate that dynamic properties of preexisting cracks provides a physical mechanism for both the rate dependent steady wave behavior and the difference between dynamic and quasistatic response.

An analysis is made of the cost estimating system currently in use at the Los Alamos Scientific Laboratory (LASL) and the benefits of computer assistance are evaluated. A computer-assisted estimating system (CAE) is proposed for LASL. CAE can decrease turnaround and provide more flexible response to management requests for cost information and analyses. It can enhance value optimization at the design stage, improve cost control and change-order justification, and widen the use of cost information in the design process. CAE costs are not well defined at this time although they appear to break even with present operations. It is recommended that a CAE system description be submitted for contractor consideration and bid while LASL system development continues concurrently.

To reduce excessive energy requirements for the implosion heating system of a theta-pinch reactor, two staging methods, the brute force and bucking field options, were proposed. A Marshall coil and a segmented coil were also considered. Calculations involved in coding these coil designs and staging options into a PL/I subprogram are described. A marked savings in the energy required for the IH system is realized with the bucking option and others.

Reflection of 50 eV to 10 keV H atoms from polycrystalline Cu, Nb and Au targets has been calculated using the binary collision cascade program MARLOWE. The fractions of particles and energy reflected (backscattered) increase with increasing atomic number of the target and decrease with increasing incident energy. The results indicate that the effects of polycrystallinity are modest, reducing the amorphous reflection coefficients by about 25 percent. The calculations agree quite well with the experimental data for Cu and Au, but are about a factor of two larger than is observed for Nb.

A computer code is developed for two-dimensional, non-steady heat conduction in heterogeneous, anisotropic solids with nonuniform volumetric internal heating. Thermal radiation and arbitrary heat flux boundary conditions are accommodated. Coolant tubes are taken into account by prescribing fluid temperatures and heat transfer coefficients. With regard to coolant tubes, allowance is made for: (a) heat capacitance in the tube wall, coolant tube in contact with the structural material; (b) zero heat capacitance in the tube wall, coolant tube in contact with the structural material; and (c) zero heat capacitance in the tube wall, radiation gap between the wall and structure. The finite difference equations are solved by the standard explicit method. Stability as well as convergence of the iterative process are considered.