Computer simulation of the three-dimensional temperature history in a multipass filled weldment was attempted by modifying a transient heat transfer code, HEATING5. The model includes temperature-dependent physical parameters, radiation and convection heat losses, turbulent and laminar convection in the molten pool, and variable arc velocity, intensity, and weld geometry. The model requires approximately 28 CPU min to simulate one second of welding. 15 figures, 8 tables.

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Magnetic thin film transient current sensor/recorders were modified to make two types of nuclear test measurements, transient currents in hybrid microcircuits and internal electromagnetic pulse (IEMP) fields. The measurements were made possible by the invention of split-domain sensor/recorders which can measure bilateral currents and can be reset and readout on location. The sensor/recorders were used in two underground nuclear tests and numerous calibration tests in radiation-simulation machines. The data showed that the nuclear environment had negligible effect on the sensor/recorder's operation and the recorded informations on the sensor/recorders were the signals intended to be monitored. Also, the experimental data agreed with the theoretical analysis in controlled experiments. The data were examined first by on location readout with a magnetic tape viewer and later by Kerr magneto-optic readout in the laboratory. To translate the data into current readings, we reconstructed facsimile data (on each of the sensor/recorders) in the laboratory by current pulses with the same pulse width as the radiation event. An additional check on the accuracy of the data was made by using both the sensor/recorder and the conventional pickup-oscilloscope-camera technique to monitor the same current lead in a simulated radiation environment. Over five runs were made, and the …

The absolute sensitivity for several different types of radiation detectors has been measured using x-rays in the energy range of 280 eV to 100 keV. The photons in this energy range are produced using three separate x-ray-generating facilities. The detectors include a silicon semiconductor, two photoelectric diode detectors employing aluminum and gold photocathodes, and three detectors incorporating plastic scintillators and photodiodes. The plastic scintillators were MEL-150C, Pilot B, and NE102.

In the numerical solution of initial-value problems in several independent variables, the timestep is controlled, especially in the presence of shocks, by a small portion of the logical mesh, what one may call the crisis zone. One is frustrated by the necessity of doing in the whole mesh frequent calculations required by only a small part of the mesh. It is shown that it is possible to choose different timesteps natural to different parts of the mesh and to advance each zone in time only as often as is appropriate to that zone's own natural timestep. Prior work is reviewed and for the first time an investigation of the conditions for well-posedness, consistency and stability in independent timesteps is presented; a new method results. The prochronic and parachronic Cauchy surfaces are identified; and the reasons (well-posedness) for constraining the Cauchy surfaces to be prochronic (as distinct from the method of Grandey), that is, to lie prior to the time of the crisis zone (the zone of least timestep), are indicated. Stability (in the maximum norm) of parabolic equations and (in the L2 norm) of hyperbolic equations is reviewed, without restricting the treatment to linear equations or constant coefficients, and stability …

An early idea for fueling a controlled fusion device had been the injection of a polarized mixture of ions and electrons across a magnetic field and into the device. Now, the beam intensity (several kA/cm/sup 2/) required for this technique is available from pulsed ion diodes. Remaining feasibility questions involve beam optics and trapping. The most obvious advantage over neutral-beam injection is avoidance of the need to produce high-energy atoms. Therefore, the technique will compete best at ion energies above 100 keV. The method appears feasible for pulsed startup of mirror machines, but not for steady-state injection into a plasma.

This trainer is a complete, self-contained microcomputer system housed in a brief case for portability and convenience of use. It utilizes INTEL's 8080A microprocessor and associated support chips. The trainer is designed to allow the student to explore and learn the hardware and software capability of the 8080 microprocessor. It includes a breadboard socket so that experiments can be interfaced to the trainer. This option allows the student to learn both interfacing techniques and programing. A keyboard and numerical display are provided for the student to communicate with the trainer. The keyboard and numerical display can be used with either the octal number system or the hexadecimal number system. 8 figures. (RWR)

An evaluation of the proposed design for the first blanket zone of the DEMO fusion device at Oak Ridge National Laboratory was performed by determining temperature profiles for a number of possible design geometries. Only one design configuration was acceptable and further evaluated by determining two-dimensional steady state temperature and tritium concentration profiles within the unit. The transient response of this design during periods of plasma shutdown was also determined to evaluate the maximum and minimum possible stress on the stainless steel cooling tubes. The preponderance of unacceptable designs of those investigated led to the recommendation that future studies consider only modules less than 25 cm thick and coolant temperature rises less than 67/sup 0/C.

Temporally and spectrally resolved x-ray emission is an important diagnostic tool for the study of target heating and compression induced by sub-nanosecond laser pulses. The use of the Livermore 15 psec x-ray streak camera to record x-ray emissions in the 1-10 keV range is described. In particular, significant progress is reported during the past year in defining the camera as a quantitative diagnostic instrument, and its implementation for multi-channel, time resolved K-edge filter measurements. Data will be presented which describe x-ray emission from a laser imploded 87 ..mu..m diameter glass shell. Channels centered at 2.6, 4.0 and 5.3 keV provide temporal information which is related to the absorption and compression phases of laser heating. The relative spectral content is found to be in agreement with standard, time integrated measurements.

The continuous-point-source computer code calculates concentrations and surface deposition of radioactive and chemical pollutants at distances from 0.1 to 100 km, assuming a Gaussian plume. The basic input is atmospheric stability category and wind speed, but a number of refinements are also included.

A preliminary design of the ZnSe cycle for thermochemical hydrogen production has been prepared for use in deriving economic costs for hydrogen production. The process flowsheet identifies key equipment items as well as major streams. Flow and heat loads have been estimated based on one mole of hydrogen output. The thermal efficiency of this cycle depends on two factors: (1) the ability to perform the dissolution of ZnSO/sub 4/ and the hydrolysis of ZnSe with a minimum amount of aqueous HCl, and (2) the ability to match the process heat requirements with available heat from the exothermic steps in the cycle. Estimates of the cycle's thermal efficiency range from 34--57 percent depending upon the process heat utilization.

Analytic solutions are dervied for plasma flows in a spherical laser target, emphasizing the region which lies between the ablation surface and the critical density surface. Electron thermal conductivity dominates the heat transport in this zone. Both classical electron thermal conduction and flux-limited conduction are treated in which the finite electron thermal velocity provides an upper bound to the heat flux. These analytic solutions are compared with computational results from 1-D hydrodynamics calculations. Finally, the implications of these solutions for growth rates of plasma instabilities in the conduction region are considered.

Current techniques for manufacturing off-axis paraboloids are both expensive and insufficiently accurate. An alternative method, turning the workpiece about its axis on a diamond-turning machine, is presented, and the equations describing the necessary tool movement are derived. A discussion of a particular case suggests that the proposed technique is feasible.

Pulsed nuclear magnetic resonance spectroscopy has been used to measure the glass transition temperatures of cured epoxy resins. These measurements make it possible to monitor the cure and determine the glass transition temperature as a function of the curing conditions and the concentration of the components. Knowledge of the glass transition temperature of the cured epoxies allows screening of them for a number of uses, including adhesives and coatings operations.

To increase the reliability of the criticality monitoring system in a diagnostic chemistry area and to reduce the number of false alarms, a new monitoring system was built using a fast-neutron detector. This paper outlines the design requirements, describes the plastic scintillation detector system as it was built, and reports on the results of several months of operation. The new monitor has proven much more useful than the gamma-detector system it replaced.

Available information defining the state of the art of encapsulation materials and processes for terrestrial photovoltaic devices and related applications were collected and analyzed. Based on criteria of properties, processability, availability, and cost, candidate materials were identified which have potential for use in encapsulation systems for low-cost, long-life terrestrial photovoltaic arrays manufactured by automated, high-volume processes. The criteria for consideration of the encapsulation systems were based on the goals for arrays with a lifetime of over 20 years high reliability, an efficiency greater than 10 percent, a total array price less than $500/kW, and a production capacity of 5 x 10/sup 5/ kW/yr. (WDM)

During the past year we have studied the effect of pH and inorganic carbon concentration on the photosynthesis of Elodea densa. In the pH range of 6 to 9, there is a dramatic change in the response of photosynthesis to pH. At 1 mM inorganic carbon and below photosynthesis increases with decreasing pH as expected, but at 10 mM and above there is a peak. This peak is between pH 7.5 and 8.0 when the inorganic carbon concentration is 10 to 20 mM and shifts to lower pH's with increasing temperature and decreasing inorganic carbon concentration. At a given temperature the calculated concentration of free CO/sub 2/ is the same at those carbon levels studied. Calculations and experiments have indicated that the presence of lacunae is not a major source of error in our system under the conditions used.

The object of this program is to demonstrate that large single-crystal ingots, 6-inch diameter by 4 inches tall, can be economically cast by the Heat Exchanger Method (HEM) and economically sliced into thin sheets, 0.008-inches thick, with a multi-wafer slicer. The thrust of the experimental work during this quarter was to establish the proper seed meltback and to nucleate single-crystal growth off the seed. Slicing tests were begun on the multi-blade wafering machine, using a newly fabricated sensitive feed mechanism and associated components. (WDM)

This research demonstrates the feasibility of using homogeneously-generated fission fragments to simulate high-fluence fusion neutron damage in niobium tensile specimens. This technique makes it possible to measure radiation effects on bulk mechanical properties at high damage states, using conveniently short irradiation times. The primary knock-on spectrum for a fusion reactor is very similar to that produced by fission fragments, and nearly the same ratio of gas atoms to displaced atoms is produced in niobium. The damage from fission fragments is compared to that from fusion neutrons and fission reactor neutrons in terms of experimentally measured yield strength increase, transmission electron microscopy (TEM) observations, and calculated damage energies.

Dr. John W. Shupe, Univ. of Hawaii, the first of seven speakers, reviewed geothermal sources in Hawaii by means of a slide presentation. Prof. Hamilton Hess, University of San Francisco, dealt philosophically with geothermal energy, considered an ''exotic alternative, or at best, a marginal energy source.'' Robert G. Lacy, San Diego Gas and Electric Co., discussed geothermal development in the Imperial Valley. Dr. Tsvi Meidav, Geonomics, Inc., discussed the size of the geothermal resource and how far away full utilization of the resource is. Donald Finn, Geothermal Energy Institute, presented slides of geothermal sources ranging from areas in New England to the geysers in the western U.S.; he touched on some legal aspects about leasing areas for geothermal development. John Aldridge, Nevada Power Co., discussed further the legal impediments to geothermal development, with comments especially on the Geothermal Steam Act of 1970. Jim Breesee, Acting Director, Division of Geothermal Development, ERDA commented further on ERDA's program. The questions asked and answered in the panel discussion that followed are presented. (MCW)

The equilibrium constant, K/sub HDO/, for the reaction H/sub 2/O + D/sub 2/O = 2HDO can be expressed as an intensity ratio, I, measured mass spectrometrically, times a sensitivity ratio, S, measured in mass spectrometric calibration experiments. The latter is difficult to measure and previously was assumed to be unity. The 2.4 percent discrepancy between K's from theoretical calculations and direct mass spectrometric measurements might be explained by another value of S. An indirect measurement of S using a pulsed-molecular beam quadrupole mass filter that has a unique three-chamber, three-leak gas inlet system is reported. The results show the sensitivities are probably equal and therefore S = 1. Systematic errors were found in the procedure, however, which precluded an unambiguous test of the theory.

Restricted Hartree-Fock calculations for the ground electronic states of BrH/sup +/, KrH/sup +/, and RbH/sup +/ have been carried out using carefully selected nominal atomic basis sets for the heavy atoms, supplemented with an additional orbital designed to allow for a better description of atomic distortion at intermediate internuclear separations. A flexible four-function basis set was used on the hydrogen atom. Molecular optimization was carried out for the heavy-atom distortion orbital and also for the hydrogen 2p orbital. The interatomic potentials obtained for the X /sup 2/PI state of BrH/sup +/ and the X /sup 1/..sigma../sup +/ state of KrH/sup +/ show strong molecular binding (i.e., 3-4 eV) relative to the neutral heavy atoms plus a proton. The RbH/sup +/ X /sup 2/..sigma../sup +/ calculations give a repulsive interatomic potential with dissociation to Rb/sup +/ and a neutral hydrogen atom.

In the course of the Cascade Improvement Program, many component equipment parts will be electroplated with nickel for corrosion protection. The maximum hardness which will be acceptable in the electroplated deposit is specified in Union Carbide's Job Specification JS-1396, Revision 3, entitled Electroplated Nickel Coatings on Steel Parts. The hardness specification is intended primarily as a control over both organic and inorganic impurities in the deposit. This report covers a study evaluating several of the numerous controllable variables which influence the hardness of the nickel plate deposited from a Watts-type bath. The variables tested were: 1) bath composition, 2) pH, 3) current density, 4) anode-cathode area ratio, and 5) bath temperature. Within the tested ranges of the variables studied, the pH and current density had the most influence on the plate hardness. The softest deposit was obtained with a bath pH of 1.5, a current density of 30 to 40 amperes/square foot, and with the anode-cathode area ratio in the range of 3:1 to 1:1. (auth)

An apparatus for producing small quantities of glass balloons for use as laser fusion targets is described. To produce precise quantities of the ingredients of one glass balloon, a jet of an aqueous solution of the glass constituents and a blowing agent is metered into uniformly sized drops by Rayleigh breakup. A small fraction of these uniform drops is then passed through an oven where the water is evaporated, the remaining solid material is fused into glass, and the blowing agent decomposes to blow the drop into a balloon. An analysis is made of the heat flow process and photographs of the resulting glass balloons are presented.