An extractor for accelerating 50 A of deuterium ions to 10 keV for injection into a metal-vapor charge-exchange cell has been designed. The beam-forming electrodes are convection cooled and capable of continuous service.

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. We have developed a new sample manipulation technique which rolls a thin wall sphere through 4..pi.. steradians, minimizes damage and allows easy recovery. The sphere is placed between two parallel plane surfaces formed in conductively coated silicone rubber on the ends of capillaries. Mechanical slides cause the capillaries to translate laterally and roll the ball bringing the entire surface of the sphere into a position for examination. Resolutions comparable with traditional mounting techniques are attained. A side looking, Si(Li) detector increases the utility of the system by allowing simultaneous energy dispersive x-ray microanalysis. The entire detector assembly slips between the secondary electron detector and the sphere rolling capillaries to collect x-rays from the target.

The rather extensive test program performed on the FFTF preheat control system resulted in successful sodium fill of one secondary heat transport loop on July 2, 1978. The data obtained during testing and the attendant operating experience gained resulted in some design changes and provided the information necessary to fully characterize system performance. Temperature excursions and deviations from preset limits of only a minor nature were encountered during preheat for sodium fill. The addition of the rate alarm feature was beneficial to operation of the preheat system and allowed early detection and correction of impending excursions.

Transport by groundwater is the most likely means of escape for radioactive waste contained in a geologic repository. The rock formations through which the groundwater flows are characterized by inhomogeneities on all distance scales. Large scale inhomogeneities cause pulses of dissolved pollutants to spread both in the direction of motion and transverse to it. This phenomenon is known as macroscopic dispersion. Similarly, inhomogeneities in the chemical properties of the rock will cause this spreading to be greater for species whose movement through the rock is retarded by waste rock chemical interactions. Previous risk analyses of nuclear waste disposal which have ignored macroscopic dispersion found that predicted radiation doses to individuals are very sensitive to the waste dissolution time. When macroscopic dispersion is incorporated into the analysis, however, the sensitivity of risk to dissolution time is greatly reduced. 6 figures, 2 tables.

A method for obtaining a constitutive relation that relates the flow stress to the equivalent plastic strain is developed. The method uses simple tension test data to suggest a functional form. This form is then used as a constitutive model in a computer program that simulates the tension test. The calculated results are compared with the experimental results and the functional form is refined until agreement is obtained between calculations and experiments. The importance of knowing the relationship between the flow stress and the plastic strain is discussed. A work hardening function is calibrated for 6061 T6 aluminum.

Recent experimental progress in the fields of photofission and electrofission of actinide nuclei is summarized. In particular, experimental results which throw light on the delineation of the characteristics of the giant resonances are highlighted. Measurements of especial interest in this regard include photofission cross-section studies with monoenergetic photons and electrofission yield and angular-distribution studies. 36 references.