RELAP4 is a computer code which can be used for the transient therm~l hydraulic analysis of light water reactors and related systems .. Various versions of the RELAP4 code are widely used throughout the world for experimental system analysis, reactor design,and nuclear system safety studies. RELAP4/MOD6 includes many new analytical models which were developed primarily for the analysis of the reflood phase of a PWR loss-of-coolant accident (LOCA) transient. The key feature forming the basis for the MOD6 reflood calculation is a unique moving finite differenced heat conductor. This paper will describe the development and application of the moving heat conductor mesh for use in reflood analysis.

Twenty-seven marine mammal species have been recorded for the Gulf of Mexico, including 7 Mysticetes or baleen whales, 17 Odontocetes or toothed whales, 1 Sirenian (manatee), and 1 or 2 Pinnipeds or seals. The most common species in the Gulf is Tursiops truncatus, the bottlenosed dolphin, an inshore species. Offshore, Stenella plagiodon, the spotted dolphin, is fairly common. Most other species are recorded from very few sightings or strandings. None of the endangered species is common in potential OTEC sites in the Gulf of Mexico. Twenty-two marine mammals may occur in Hawaii; 2 Mystecetes, 19 Odonotocetes, and the endemic monk seal. The monk seal (Monachus schauinslandi), an endangered species, lives in the extreme northwestern island chain away from potential OTEC sites. Among the most common cetaceans in Hawaii is the endangered humpback whale (Megaptera novaeangliae). Stenella longirostris, the spinner dolphin; and Tursiops sp., the bottlenosed dolphin are also fairly common. The baleen whales feed on zooplankton during the summer in polar waters, and are migratory, while the toothed whales feed mainly on fish and squid, and are found in temperate or tropical regions year-round. The manatee is vegetarian and the pinnipeds are fish- or squid-eaters. Environmental effects of OTEC which …

A thermodynamic and economic performance analysis code, SOLSTEP, was developed to facilitate the evaluation of solar thermal power plant designs. The code conducts a time step simulation of the plant thermodynamic performance using actual recorded meteorological and insolation data. Each analysis case provides capacity factor and levelized energy cost results for several plant configurations using various combinations of collector field size and storage capacity. The code has been used to analyze a variety of solar thermal generic concepts involving several collector types and energy conversion and storage subsystems.

The in-situ thermal conductivity and thermal diffusivity of a granite rock mass at the Stripa mine, Sweden, have been extracted from the first 70 days of temperature data for the 5 kW full-scale heater experiment by means of least-squares fit to a finite-line source solution. Thermal conductivity and thermal diffusivity have been determined to be 3.69 W/(m-/sup 0/C) and 1.84 x 10/sup -6/ m/sup 2//s, respectively, at an average rock temperature of 23/sup 0/C (the average value of the actual temperature data used). These values are only slightly higher than the corresponding laboratory values, i.e., there is no significant size effect in the thermal properties of this rock mass. Since the size and shape of the heater canister used are similar to those considered for nuclear waste canisters and a substantial volume of rock is heated, the thermal properties obtained in this study are representative of in-situ rock mass properties under actual nuclear repository operating conditions.

Fresnel zone plate patterns, free of spherical abberation, with diameters of up to 0.63 mm and linewidths as small as 1000 A were fabricated on polyimide-membrane x-ray masks using scanning electron beam lithography Distortion of the electron beam scan raster was reduced to < 2500 A over a 2 mm x 2 mm field by applying deflection corrections, while viewing the distortion using a moire method. C/sub k/ x-ray lithography was used to replicate the zone plate pattern in thick PMMA over a 100 A thick plating base on a glass substrate. Zones plates in 1.3 ..mu..m thick gold were fabricated by plating, and made free-standing by removal of the plating base and the supporting glass substrate. Zone plates were tested as imaging elements with visible light and soft x-rays.

This paper discusses decontamination methods for LWRs. Emphasis is on the chemical cleaning of primary systems and contaminated equipment and components. The equipment is composed primarily of stainless steel, Inconel, Zircaloy, and a few other materials. Variables affecting efficiency are discussed. 10 figures. (DLC)

Substantial differences have been found between measured and computed heat losses from a large in-ground thermal storage tank used for annual cycle heat storage. One suspected source of error in the computation was the neglect of the latent heat effects in the moist soil and efforts have been made to examine these. One of these effects, that was due to freezing and thawing of the soil moisture is discussed, and the results of some simulations of the effect in a numerical model are presented.

The spermatogonial cell renewal system can maintain function and a steady level of cell population for relatively long periods of continuous low-level irradiation indicating that there does not appear to be a serious accumulation, over many generations, of damage affecting proliferation. Provided the dose-rate is quite low, there is an effective selective removal of damaged cells with almost complete repair of cellular nonlethal damage. At dose-rates greater than 2 rad/day, spermatogonia are very sensitive to radiation death, and the main reason for the low tolerance to continuous stress could, in part, be the limited extent of compensatory mechanisms regulating spermatogonial cell production. However, there is some capacity to change the patterns of cellular proliferation while still remaining under homeostatic control, and this capacity appears to reside in the relatively radioresistant A/sub s/ stem-cell population. Little is known about the extent to which the spermatogonial cell population can repair nonlethal cellular radiation damage accumulated under continuous stress affecting the regenerative capacity of the tissue. After acute exposure, a minimum number of surviving type A/sub s/ stem-cells are required to repopulate the functional seminiferous epithelium, regeneration proceeds along an ordered cell stage sequence, and is dependent on the time required for all …

Theoretical aspects of the measurements of production of low transverse momentum secondaries in high-energy hadron-nucleus and nucleus-nucleus collisions are discussed. Applications of the quark model to those processes are discussed in some detail. 58 references.

High power pulse copper vapor laser systems consist of a master oscillator and numerous power amplifiers. Large systems used in laser isotope separation experiments require several automatic control systems. The rapid development of compact mini computers over the past several years has enabled the implementation of sophisticated computer controlled copper vapor laser systems. Present systems provide automatic time synchronization and input power stabilization. Future systems will incorporate semi-automatic start-up capabilities.

The gamma-ray component of the reactor radiation field can produce effects which impact strongly upon reactor design, shielding, and safety. Radiation effects arising from the gamma-ray component are induced by interaction of the absolute gamma-ray energy spectrum in the reactor environment. Hence, the most fundamental quantity underlying effects produced by the reactor gamma-ray field is the absolute gamma-ray energy continuum. To this end, the current status of Compton recoil gamma-ray spectrometry in Light Water Reactors (LWR) and Fast Breeder Reactors (FBR) environments is described. Particular emphasis is given to continuous gamma spectometry experiments in a LWR pressure vessel mockup at the Oak Ridge National Laboratory Poolside Critical Assembly (PCA). Gamma spectrometry plans for FBR environments are outlined with special attention placed on start-up experiments in the Fast Test Reactor (FTR). Improvements in Compton recoil gamma-ray spectroscopy are presented.

The emphasis of much of the current and planned research on the toxicity of alpha-emitting radionuclides is directed toward the complexities of actual and potential conditions of occupational environmental exposures of human beings. These, as well as the more limited studies on mechanisms of biological transport and effects, should increase our ability to predict health risks more accurately and to deal more confidently with human exposures, if and when they occur.

Associated with commercial nuclear power production in the United States is the generation of potentially hazardous radioactive wastes. The Department of Energy (DOE), through the National Waste Terminal Storage (NWTS) Program, is seeking to develop nuclear waste isolation systems in geologic formations that will preclude contact with the biosphere of waste radionuclides in concentrations which are sufficient to cause deleterious impact on humans or their environments. Comprehensive analyses of specific isolation systems are needed to assess the expectations of meeting that objective. The Waste Isolation Safety Assessment Program (WISAP) has been established at the Pacific Northwest Laboratory (operated by Battelle Memorial Institute) for developing the capability of making those analyses. Among the analyses required for isolation system evaluation is the detailed assessment of the post-closure performance of nuclear waste repositories in geologic formations. This assessment is essential, since it is concerned with aspects of the nuclear power program which previously have not been addressed. Specifically, the nature of the isolation systems (e.g., involving breach scenarios and transport through the geosphere), and the time-scales necessary for isolation, dictate the development, demonstration and application of novel assessment capabilities. The assessment methodology needs to be thorough, flexible, objective, and scientifically defensible. Further, the …

The importance of experiments detecting more than one particle is pointed out. The production of nuclei far from stability in peripheral collisions and the expectations for the explosive disassembly of dense nuclear matter (nuclear fireball) and some evidence for it are related. Pion interferometry concerns the measurement of correlations in the momentum and energy of two identical pions; the subject is discussed in relation to incoherent production, coherent production, partially coherent production, final-state interactions, impact parameter average, and outlook. Much of the paper deals with an assessment of the possibility of determining the form of the hadronic spectrum in the high-mass region through nuclear collisions at ultrarelativistic energies. The subject is developed under the following topics: perspective, the initial fireball, isoergic equilibrium expansion of the fireball, quasi-dynamical expansion, quark matter, and the mass degree of freedom. The quasi-dynamical model obtained indicates that certain parameters, such as the ..pi../N and K/N ratios at high kinetic energy, will survive the collision; therefore, a determination of the asymptotic form of the hadron spectrum probably can be made by studying nuclear collisions at very high energies (10 GeV/nucleon in the center of mass). 16 figures. (RWR)

Ways of detecting tau neutrinos emerging from a beam dump are studied. Key signatures are elaborated and contrasted with background arising from muon and electron neutrino interactions. Expected event rates are given for various neutrino spectra. 16 references.

Interactions of chemicals and radiation are complex and there may exist other unexpected patterns that are not mentioned. We show some examples. Photodynamic mutation induction by fluorescein dyes and Radiosensitization with iodine compounds are classified as Interactions of chemicals and radiation outside of the cell. On the other hand, the Antimutagenic effects of cobaltous chloride is concerned with events taking place in cells that had already been exposed to a mutagenic agent. It is likely that the action of a mutagenic agent is not direct and that cellular functions, such as mutators or repair systems, are involved in the mutagenesis initiated by the agent. Such cellular functions can be affected by a second agent. In sexually reproducing organisms, the two agents can also act on separate cells (male and female germcells) which subsequently fuse. Interaction effects of all types will be useful in future research in shedding light on the main pathways of mutagenesis.

Analytical chemists have devoted considerable effort to develop detailed analysis of hydrocarbons in tissues. The methods developed are time consuming, and there is often a high degree of variability between samples. In light of this, the cost effectiveness of these analyses is questioned. The need to simplify tissue analysis is discussed. Data are provided on a number of benthic marine organisms exposed to continuous contamination with crude oil and problems of individual organism variability are discussed.

A computer model SHADE (Selection of Heliostat Arrangement for Distributed Engines) has been developed at the Pacific Northwest Laboratory to aid in determining the optical performance of two-axis tracking parabolic concentrators. The shading of individual mirror assemblies in a field of parabolic dishes determines the optimal field arrangement and the most efficient method of plant operation. SHADE provides a simple and inexpensive analytical tool for examining certain design aspects of solar thermal power systems using a network of point-focusing parabolic concentrators.

Inertial confinement fusion requires production of power plant grade targets at high rates and process yield. A review of present project specifications and techniques to produce targets is discussed with special emphasis on automating the processes and combining them with an electrostatic transport and suspension system through the power plant target factory.

The seasonal sensible heat storage model developed by F.C. Hooper and C.R. Attwater is modified to describe the thermal behaviour of the soil regime surrounding cylindrical, in-ground, heat storage tanks with optimally distributed insulation. The model assumes steady-state heat transfer, and the surrounding soil is considered to be homogeneous and isotropic. Changes in soil thermal properties due to moisture migration, whether driven by thermal or hydrostatic gradients, are assumed negligible. The optimal distribution is determined using the method of Lagrange multipliers. It is shown that the marginal cost per unit of energy lost and per unit of tank surface area must be the same at all points on the surface of the tank as the condition for minimum total heat loss with a given total investment in insulation. This condition appears to apply for all axi-symmetric in-ground tank geometries. For a given volume of insulation, the incremental increase in storage efficiency with an optimal redistribution of the insulation is a function of tank geometry. The problem of determining the optimal total investment in insulation for a given marginal cost of fuel is described and a method of solution is outlined.

Oxygen-to-metal ratio (O/M) of mixed oxide fuel pellets can be controlled during fabrication by proper selection of binder (type and content) and sintering conditions. Sintering condition adjustments involved the passing of Ar--8% H/sub 2/ sintering gas across a cryostat ice bath controlled to temperatures ranging from -5 to -60/sup 0/C to control as-sintered pellet O/M ratio. As-sintered fuel pellet O/M decreased with increasing Sterotex binder and PuO/sub 2/ concentrations, increasing sintering temperature, and decreasing sintering gas dew point. Approximate relationships between Sterotex binder level and O/M were established for PuO/sub 2/--UO/sub 2/ and PuO/sub 2/--ThO/sub 2/ fuels. O/M was relatively insensitive to Carbowax binder concentration. Several methods of increasing O/M using post-sintering pellet heat treatments were demonstrated, with the most reliable being a two-step process of first raising the O/M to 2.00 (stoichiometric) at 650/sup 0/C in Ar--8% H/sub 2/ bubbled through H/sub 2/O, followed by hydrogen reduction to specification O/M in oxygen-gettered Ar-(% H/sub 2/ at temperatures ranging from 1200 to 1690/sup 0/C.

Separate abstracts were prepared for 17 of the papers in these Proceedings. The remaining six have already been cited in ERA, and can be located by referring to the entry CONF-781174-- in the Report Number Index. (RWR)

A multiple-computer data acquisition system is described. The use of multiple central processors, distributed intelligence in a CAMAC system, and large external memories is illustrated. 1 figure.

The problems involved in designing an experiment using cosmic-ray neutrinos to measure the y-distribution in neutrino scattering at 2 to 50 TeV, which should be capable of demonstrating the existence of the W through its propagator effect on the y-distribution is discussed in detail. 19 references.