Intrinsic tracer impurity diffusion measurements in ceramic oxides have been primarily confined to CoO, NiO, and Fe/sub 3/O/sub 4/. Tracer impurity diffusion in these materials and TiO/sub 2/, together with measurements of the effect of impurities on tracer diffusion (Co in NiO and Cr in CoO), are reviewed and discussed in terms of impurity-defect interactions and mechanisms of diffusion. Divalent impurities in divalent solvents seem to have a weak interaction with vacancies whereas trivalent impurities in divalent solvents strongly influence the vacancy concentrations and significantly reduce solvent jump frequencies near a trivalent impurity. Impurities with small ionic radii diffuse more slowly with a larger activation energy than impurities with larger ionic radii for all systems considered in this review. Cobalt ions (a moderate size impurity) diffuse rapidly along the open channels parallel to the c-axis in TiO/sub 2/ whereas chromium ions (a smaller-sized impurity) do not. 60 references, 11 figures.

The Pacific Northwest Laboratory is conducting a comprehensive study of the impacts, benefits and effects of decontamination as a precursor to decommissioning for the US Nuclear Regulatory Commission. The program deals primarily with chemical cleaning of light-water reactor (LWR) systems that will not be returned to operation. A major section of this study defines the health physics and industrial hygiene and safety concerns during decontamination operations. The primary health physics concerns include providing adequate protection for workers from radiation sources which are transported by the decontamination processes, estimating and limiting radioactive effluents to the environment and maintaining operations in accordance with the ALARA philosophy. Locating and identifying the areas of contamination and measuring the radiation exposure rates throughout the reactor primary system are fundamental to implementing these health physics goals. The principal industrial hygiene and safety concerns stem from the fact that a nuclear power plant is being converted for a time to a chemical plant which will contain large volumes of chemical solutions.

Positron-annihilation characteristics in a monovacancy and a divacancy in aluminium have been calculated self-consistently using a local density functional formalism, into which the many-body enhancement effects have been incorporated. Results for the theoretical two-dimensional angular correlation of annihilation radiation spectra are compared to experimental results obtained from an aluminum single crystal at 20/sup 0/C, where positrons annihilate from a Bloch-state, and at higher temperatures, 500/sup 0/C and 630/sup 0/C, where they annihilate primarily from vacancy-trapped states.

Separate abstracts were prepared for the 47 papers presented. (WHK)

There has been intense interest in re-entrance and coexistence in ternary rare earth magnetic superconductors of the form RE Rh/sub 4/B/sub 4/. Of particular interest in this investigation is the effect of the superconducting state on the RKKY (Yosida, 1957) coupling between RE ions. Since one expects the conduction electron spin susceptibility chi/sup e/(q) to be cut off for q < 1/xi in the superconducting state, a depression f the RKKY coupling should follow. Such an effect would both depress the magnetic ordering temperature and result in slower relaxation rates tau/sub m//sup -1/ for the RE moments in the superconducting state. This paper reports on the spin dynamics of the RE ions using the /sup 11/B nuclear magnetic relaxation rate T/sub 1//sup -1/ in dilute Y/sub 1-x/RE/sub x/Rh/sub 4/B/sub 4/ (RE = Gd and Er).

A density functional scheme has been developed for incorporating electron-positron correlation effects into band-structure calculations of positron-annihilation characteristics. The electron and positron densities are determined from a self-consistent set of equations based on a generalized Kohn-Sham scheme. Application of this formalism to defect-free aluminum is described. The results for a two-dimensional angular-correlation spectrum and the positron lifetime show very good agreement with experiment. The method is of general applicability and can be used with any existing self-consistent band-structure scheme.

Positron annihilation spectroscopy (PAS) has made significant contributions to our knowledge regarding lattice defects in metals in two areas: (i) the determination of atomic defect properties, particularly those of monovacancies, and (ii) the monitoring and characterization of vacancy-like microstructure development during post-irradiation of post-quench annealing. The application of PAS to the study of defects in metals is selectively reviewed and critically assessed within the context of other available techniques for such investigations. Possibilities for using the positron as a localized probe of the structure of atomic defects are discussed. Finally, the present status and future potential of PAS as a tool for the study of defects in metals are considered relative to other available techniques. 92 references, 20 figures.

The natural circulation tests of the Fast Flux Test Facility (FFTF) demonstrated a safe and stable transition from forced convection to natural convection and showed that natural convection may adequately remove decay heat from the reactor core. The COBRA-WC computer code was developed by the Pacific Northwest laboratory (PNL) to account for buoyancy-induced coolant flow redistribution and interassembly heat transfer, effects that become important in mitigating temperature gradients and reducing reactor core temperatures when coolant flow rate in the core is low. This report presents work sponsored by the US Department of Energy (DOE) with the objective of checking the validity of COBRA-WC during the first 220 seconds (sec) of the FFTF natural-circulation (plant-startup) tests using recorded data from two instrumented Fuel Open Test Assemblies (FOTAs). Comparison of COBRA-WC predictions of the FOTA data is a part of the final confirmation of the COBRA-WC methodology for core natural-convection analysis.

We begin with a discussion of e/sup +/e/sup -/ annihilation into hadrons, a process blessed with well-known elements of simplicity. We consider the opposite extreme of highly relativistic nucleus-nucleus collisions. Here a space-time description has its own elements of simplicity, elements which might conceivably be applicable in hadron-hadron collisions. We also address the more immediate issues of how these ideas relate to present-day observations, especially high-energy hadron-hadron collisions. 40 references.

Materials presented at the workshop are included here: International Petroleum Exchange Model: Nazli Choucri; Gas Research Institute, 1983 Baseline Projection: Daniel A. Dreyfus; Energy Information Administration, Annual Report to Congress, 1981: W. Calvin Kilgore; PILOT Oil Import Demand Scenario Results: George Dantzig; and DRI Energy Review, Summer 1981: Roger Brinner.

The barrier penetration factor for the fusion reaction of ..mu..-mesic hydrogen atoms with hydrogen nuclei is studied. (MOW)

A brief discussion of the use of aluminium walls in fusion reactors is presented. The topics considered are related to maintenance, safety, and waste disposal. (MOW)

The off-gas characteristics of liquid-fed joule-heated ceramic melters have been investigated as a function of melter operational condition and simulated waste feed composition. The results of these studies have established the identity and behavior patterns of gaseous emissions, the characteristics of melter-generated aerosols, the nature and magnitude of melter effluent losses and the factors affecting melter operational performance. 8 figures, 16 tables.

Conceptual design studies have been carried out on an integrated fusion/chemical plant system using a Tandem Mirror Reactor fusion energy source to drive the General Atomic Sulfur-Iodine Water-Splitting Cycle and produce hydrogen as a future feedstock for synthetic fuels. Blanket design studies for the Tandem Mirror Reactor show that several design alternatives are available for providing heat at sufficiently high temperatures to drive the General Atomic Cycle. The concept of a Joule-boosted decomposer is introduced in one of the systems investigated to provide heat electrically for the highest temperature step in the cycle (the SO/sub 3/ decomposition step), and thus lower blanket design requirements and costs. Flowsheeting and conceptual process designs have been developed for a complete fusion-driven hydrogen plant, and the information has been used to develop a plot plan for the plant and to estimate hydrogen production costs. Both public and private utility financing approaches have been used to obtain hydrogen production costs of $12-14/GJ based on July 1980 dollars.

Currently, studies are underway at the Lawrence Livermore National Laboratory (LLNL) on thermochemical hydrogen production based on magnetic fusion energy (MFE) and solar central receivers as heat sources. These areas of study were described earlier at the previous IEA Annex I Hydrogen Workshop (Juelich, West Germany, September 23-25, 1981), and a brief update will be given here. Some basic research has also been underway at LLNL on the electrolysis of water from fused phosphate salts, but there are no current results in that area, and the work is being terminated.

Particle motion in the ELF wiggler was investigated numerically and analytically. A transport system was designed using continuous quadrupole focusing in the wiggle plane and natural wiggle focusing in the non-wiggle plane.

The techniques and models used in the study of rapid reactivity insertion in a BWR have ranged from approximate conservative methods with simple feedback models to detailed representations of coupled neutronic thermal-hydraulic mechanisms. In a recent paper Cheng and Diamond presented a detailed evaluation of the control rod drop accident (CRDA). Their calculations suggested that the effect of inlet subcooling and rod drop speed may play an important role in determining the severity of the rod drop accident. The purpose of the work summarized in this paper has been to determine in detail the dynamic behavior of a BWR core as the inlet moderator temperature and the speed of the dropped rod are varied.

A successful experimental program has been initiated on the filter difference spectrometer. The instrument is most appropriate for energy transfers from about 50 to 600 MeV when moderate energy resolution is sufficient and a high count rate of importance. The difference technique is well enough understood so that peak positions, line widths and integrated intensities can be determined from fairly complex spectra. Several improvements to the instrument are in progress. An important change will be cooling of the sections which is expected to give approximately a factor of two increase in signal. The solid angle subtended by the detector banks will also be increased by a factor of 1.7 without significant degradation in resolution. With these improvements, much smaller samples can be examined in cases where material is unavailable in larger quantities, as well as samples with much small scattering cross sections. The major improvement will come when the proton storage ring becomes operational in 1985. A total increase of approximately 100 in neutrons detected will allow much more difficult experiments to be performed on this instrument with still a fast turnover rate.

A preliminary report is presented of a positron-annihilation study of the equilibrium vacancy ensemble in aluminum using one- and two-dimensional angular correlation of annihilation radiation (ACAR) measurements versus temperature. The annihilation characteristics of a positron from the Bloch state, and the monovancy- and divacancy-trapped states have been calculated self-consistently within a supercell, including many-body enhancement effects, and are compared with experiment. 4 figures.

A charge-particle beam contained in an accelerator vacuum chamber interacts electromagnetically with its environment to create a wake field. This field than acts back on the beam, perturbing the particle motion. If the beam intensity is high enough, this beam-environment interaction may lead to an instability and to subsequent beam loss. The beam and its environment form a dynamical system, and it is this system that will be studied. 84 references.

The Nova laser will have a large pulse power system for driving laser amplifiers, incorporating approximately 1600 flashlamp circuits. An automated system has been designed for diagnosing the condition of these flashlamp circuits. It records digitized circuit current waveforms and detects current excursions above a given threshold. In addition, it is able to fire flashlamps at a low energy to ascertain the health of the system. Data from this system can be ploted for inspection by the operator, analyzed by the computer system and archived for future reference.

We have produced a series of reactor designs to meet the variety of driver-target combinations that could possibly result from the inertial-confinement fusion program. In this paper we discuss four reactor designs, the goals of which are low cost; a low probability of risk to the public, the plant employees, and the utility investment; and a minimal environmental impact under normal plant operation. HYLIFE is a low pulse rate, lithium-cooled reactor. Pulse*Star and Cascade are high pulse rate reactors. In Pulse*Star, fusion energy is absorbed in the PbLi pool; in Cascade it is absorbed by Li/sub 2/O particles. Sunburst, a very low pulse rate, lithium-cooled reactor, directly converts over 40% of the fusion energy to electricity using a pulsed magnetic field.

The quantitative estimation of the carcinogenic risk of low-dose, high-LET radiation in the case of exposure to radon daughters and lung-cancer is subject to numerous uncertainties. The greatest of these concerns the parametric values of the dose-response curve. We lack knowledge and an understanding of the dosimetry and the distribution of aggregates of radioactivity that remain localized as hot spots in specific regions of the lungs and the influence on greater or lesser risk of lung cancer per average lung dose than uniformly deposited radiation (NRC76). We have only a limited understanding of the response to exposure to high-LET radiations, such as alpha particles, for which linear risk estimates for low doses are less likely to overestimate the risk, and may, in fact, underestimate the risk (BEIR80). Other uncertainties include the length of the latency period, the RBE for alpha radiation relative to gamma radiation, the period during which the radiation risk is expressed, the risk projection model used - whether absolute or relative - for projecting risk beyond the period of observation, the effect of dose rate and protraction of dose, and the influence of differences in the natural incidence of lung cancer in different populations. In addition, uncertainties …

A report on the impact upon LBL of the policy changes and budget actions in Department of Energy programs since early 1981 is given, and some views are given on more general problems that appear to underlie the interaction between the federal government, which supports research, and the scientific community, which performs it. (WHK)