High quality TRISCO-coated UCO and ThO{sub 2} particles with reference MHTGR dimensions were produced in a coating campaign in August and September 1986 for irradiation tests. The heavy metal contamination and the defect levels were below the limits established for the MHTGR fuel. Over 9 kg of uranium in UCO and 30 kg of thorium in ThO{sub 2} were TRISCO-coated in 4 fissile and 3 fertile batches in the 240mm Development Coater. These coated fuel particles will be used to produce fuel rods for testing in the irradiation validation tests to be conducted in capsules HRB-19, -20 and -21 on the DOE Fuel and Fission Product Technology Program. 3 refs., 6 figs., 6 tabs.

This report presents results of an analytical study on hydrological transport of a radionuclide released from sources of finite areal extent into a planar fracture. The purposes of this work are to predict the space-time-dependent concentrations of a radionuclide which is released from multiple-patch (or area) sources and transported by advection and transverse dispersion in a planar fracture and by molecular diffusion in rock matrix, and to investigate the effects of transverse dispersion in the fracture. 5 refs., 14 figs.

A bounce-averaged Monte Carlo operator is presented that simulates bounce-averaged perturbative Lorentz pitch angle scattering of particles in toroidal plasmas, in particular a tokamak. In conjunction with bounce-averaged expressions for the deterministic motion, this operator allows a quick and inexpensive simulation on time scales long compared to a bounce time. An analytically tractable model of transport due to toroidal magnetic field ripple is described.

The structural design of the large HTGR prismatic core fuel elements involve the interaction of four engineering disciplines: nuclear physics, thermo-hydraulics, structural and material science. Fuel element stress analysis techniques and the development of structural criteria are discussed in the context of an overview of the entire design process. The core of the proposed 2240 MW(t) HTGR is described as an example where the design process was used. Probabalistic stress analysis techniques coupled with probabalistic risk analysis (PRA) to develop structural criteria to account for uncertainty are described. The PRA provides a means for ensuring that the proposed structural criteria are consistent with plant investment and safety risk goals. The evaluation of cracked fuel elements removed from the Fort St. Vrain reactor in the USA is discussed in the context of stress analysis uncertainty and structural criteria development.

Evidence is shown for the observation of five-closely spaced states in /sup 118/Cd with a centroid at 1989 keV which may represent the first identification of all five members of the three-phonon quintuplet. 11 refs., 2 figs.

Data from e/sup +/e/sup -/ collisions collected by the MAC detector at the SLAC storage ring PEP with a new vertex chamber having position resolution of 50 ..mu..m have been analyzed with a new method to make a determination of the lifetime of hadrons containing b-quarks. In addition, data collected with MAC before the vertex chamber was installed have been re-analyzed using the new method. The combined result for the B lifetime is tau/sub b/ = (1.16 +- 0.16(stat.) +- 0.07(syst.)ps) x (1 +- 0.15), where the last factor is the scale. 12 refs., 2 figs.

Quantitative analyses of angular distributions and angle-mass correlations have been applied to the U + Ca reaction to obtain upper limit estimates for the cross sections for complete fusion near or below the interaction barrier. Extrapolating to the systems Ca + Cm and Ca + Es using the well established scaling properties of the extra push model, an estimate of the cross sections relevant to the efforts of synthesizing super-heavy elements in the region Z = 116 and N = 184 via heavy-ion fusion reactions are obtained. A simple evaporation calculation using properties of the super heavy elements shows that the failure to observe super-heavy elements with the Ca + Cm reaction is consistent with estimates of the complete fusion process. 33 refs., 9 figs., 1 tab.

The surface magneto-optic Kerr effect (SMOKE) is used to explore the magnetism of ultra-thin Fe Films extending into the monolayer regime. Both bcc ..cap alpha..-Fe and fcc ..gamma..-Fe single-crystalline, multilayer films are prepared on the bulk-terminated (1 x 1) structures of Au(100) and Cu(100), respectively. The characterizations of epitaxy and growth mode are performed using low energy electron diffraction and Auger electron spectroscopy. Monolayer-range Fe/Au(100) is ferromagnetic with a lower Curie temperature than bulk ..cap alpha..-Fe. The controversial ..gamma..-Fe/Cu(100) system exhibits a striking, metastable, surface magnetic phase at temperatures above room temperature, but does not exhibit bulk ferromagnetism.

We study the use of such compounds in the strong, permanent magnet multipoles required for handling high energy, charged particle beams. We have made a number of SmCo/sub 5/ multipoles which have been used in a variety of ways, e.g., sextupoles for chromatic correction of the SLAC damping rings and quadrupoles for matching their associated injection and extraction lines. For applications in high radiation areas, we have used VACOMAX 170 thermally stabilized at 80/sup 0/C. Because our fabrication method uses measured characteristics of individual blocks in isolation, linearity over the operating range of the B-H curve is important. Stronger PM materials or multipole magnets increase the operating range which decreases linearity and increases unwanted harmonics. To study such effects, multipole magnets of VACODYM 370 are being made at different radii to emphasize high field effects which can drive parts of a magnet well into the third quadrant of the B-H curve. The results are compared to calculations based on various assumptions and our previous results for SmCo.

Spent fuel is being considered as a waste form for disposal in a repository located in salt. To adequately model spent fuel performance as a waste form that may be contacted by brine in a repository, it is necessary to describe the leach (dissolution) behavior of spent fuel and the chemical interactions of the released radionuclides with their environment. To this end, leach tests were conducted on: UO/sub 2/ in Permian Basin salt brine or deionized water at test temperatures of 25, 75, and 150/sup 0/C. Some tests were done in the presence of ductile cast iron, which is a representative overpack material, and/or oxidized Zircaloy, which is the usual fuel cladding material. Spent fuel (H.B. Robinson) in Permian Basin salt brine at 25 and 75/sup 0/C. Some of the tests were conducted in the presence of ductile cast iron. The release values for leach periods up to 60 days were determined for systems utilizing both UO/sub 2/ and spent fuel. This report is based upon data obtained during 1982 and 1983. The larger temperature dependence of the leach behavior that was observed for deionized water than was observed for brine is difficult to interpret on the basis of our …

A new central drift chamber has been constructed for the Mark II detector for use at the new SLAC Linear Collider (SLC). The design of the chamber is based on a multi-sense-wire cell of the jet chamber type. In addition to drift-time measurements, pulse-height measurements from the sense wires provide electron-hadron separation by dE/dx. The chamber has been tested in operation at PEP before its move to the SLC. The design and construction are described, and measurements from the new chamber are presented.

A combination of pellets, off-axis heating, and current ramp is used to delay the onset of sawtooth oscillations for 3.4 seconds and achieve ignition with less than 0.2-second confinement time in a 1-1/2-D BALDUR simulation of the Compact Ignition Tokamak. Deuterium and tritium pellets are injected into an initially cold, relatively low density plasma, where they cool the center and produce a very centrally peaked density profile. A centrally peaked density profile (n/sub e0//<n/sub e/> = 4.0) is subsequently maintained by an inward particle pinch. Twenty megawatts of auxiliary heating is applied halfway between the magnetic axis and the edge of the plasma for 2 seconds after the pellets are injected. The plasma ignites and then burns from the time the auxiliary heating is turned off until the first large sawtooth crash occurs at 3.4 seconds. The burn would be expected to continue after that only if the sawtooth period is sufficiently long (roughly 0.3 seconds or longer).

Pacific Northwest Laboratory, supported by the US Department of Energy, developed advanced materials for use in open-cycle, closed cycle magnetohydrodynamics (MHD) power generation, an advanced energy conversion system in which the flow of electrically conducting fluid interacts with an electric field to convert the energy directly into electricity. The purpose of the PNL work was to develop electrodes for the MHD channel. Such electrodes must have: (1) electrical conductivity above 0.01 (ohm-cm)/sup -1/ from near room temperature to 1900/sup 0/K, (2) resistance to both electrochemical and chemical corrosion by both slag and potassium seed, (3) resistance to erosion by high-velocity gases and particles, (4) resistance to thermal shock, (5) adequate thermal conductivity, (6) compatibility with other channel components, particularly the electrical insulators, (7) oxidation-reduction stability, and (8) adequate thermionic emission. This report describes the concept and development of high-temperature, graded ceramic composite electrode materials and their electrical and structural properties. 47 refs., 16 figs., 13 tabs.

Four field theory models are studied: Periodic Quantum Electrodynamics (PQED) in (2 + 1) dimensions, free scalar field theory in (1 + 1) dimensions, the Quantum XY model in (1 + 1) dimensions, and the (1 + 1) dimensional Ising model in a transverse magnetic field. The last three parts deal exclusively with variational methods; the PQED part involves mainly the path-integral approach. The PQED calculation results in a better understanding of the connection between electric confinement through monopole screening, and confinement through tunneling between degenerate vacua. This includes a better quantitative agreement for the string tensions in the two approaches. Free field theory is used as a laboratory for a new variational blocking-truncation approximation, in which the high-frequency modes in a block are truncated to wave functions that depend on the slower background modes (Boron-Oppenheimer approximation). This ''adiabatic truncation'' method gives very accurate results for ground-state energy density and correlation functions. Various adiabatic schemes, with one variable kept per site and then two variables per site, are used. For the XY model, several trial wave functions for the ground state are explored, with an emphasis on the periodic Gaussian. A connection is established with the vortex Coulomb gas of …

The purpose of the Performance Evaluation of Electrical Equipment during Severe Accident States Program is to determine the performance of electrical equipment, important to safety, under severe accident conditions. In FY85, a method was devised to identify important electrical equipment and the severe accident environments in which the equipment was likely to fail. This method was used to evaluate the equipment and severe accident environments for Browns Ferry Unit 1, a BWR/Mark I. Following this work, a test plan was written in FY86 to experimentally determine the performance of one selected component to two severe accident environments.

A review is presented of data and theoretical interpretations of the nuclear dependence of quark and antiquark distributions as observed in the deep inelastic scattering of neutrinos and charged leptons from nuclei. After a summary of the experimental situation and a survey of proposed explanations, the author concentrates on interpretations in terms of conventional nuclear physics and on the Q/sup 2/-rescaling approach. The review concludes with a list of desirable future experiments. 32 refs., 5 figs.

A review is given on the phenomenology of CP violation in B and D decays that has been developed over the last few years. Since a firm data base on B decays is still lacking, semiquantitative scenarios are drawn. Within the Standard Model one predicts asymmetries that can be as large as O (10%) with a confidence level that ranges between hopeful and considerable. Even so, millions of produced B and D mesons are required to make such studies feasible. A B factory would be crucial in such an endeavor. 10 refs.

The mineralogy of drill holes J-13, UE-25A No. 1, and USW G-1 was previously determined using qualitative and semiquantitative techniques, and most of the available data were neither complete nor accurate. New quantitative x-ray diffraction data were obtained for rocks from all three of these drill holes at Yucca Mountain, Nevada. These quantitative analyses employed both external and internal standard x-ray powder diffraction methods and permitted the precise determination of all phases commonly found in the tuffs at Yucca Mountain, including glass and opal-CT. These new data supplant previous analyses and include numerous additional phases. New findings of particular importance include better constraints on the distribution of the more soluble silica polymorphs, cristobalite and opal-CT. Opal-CT was associated solely with clinoptilolite-bearing horizons, and cristobalite disappearance coincided with the appearance of analcime in USW G-1. Unlike previous analyses, we identified significant amounts of smectite in drill hole J-13. We found no evidence to support previous reports of the occurrence of erionite or phillipsite in these drill holes.

As heavy ion reaction studies have progressed from beam energies below 10 MeV/nucleon to higher energies, many non-equilibrium reaction phenomena have been observed. Among these are nucleon emission with velocities in excess of the beam velocity, incomplete momentum transfer to evaporation residue and fission-like fragments, ..gamma..-rays with energies in excess of 100 MeV, and ..pi../sup 0/ production when beam energies are below the threshold for production by the nucleon-nucleon collision mechanism. Additionally, prefission neutrons have been observed in excess of numbers expected from equilibrium models. A few of the approaches which have been applied to these phenomena are as follows: Intranuclear cascade: two body collisions are assumed to mediate the equilibration. The geometry and momentum space is followed semiclassically. The approach has many successes though it may suffer in a few applications is not following holes; TDHF considers one body processes only; in the energy regime of interest, two body processes are important so that this may not be a viable approach; Boltzmann-Uehling-Uhlenbeck or Vlasov-Uehling-Uhlenbeck (BUU/VUU) equations combine both one body and two body dynamics. The spatial and momentum evolution of the reactions are followed in a mean field. These should be the Cadillacs of the models. They are computationally …

Precompound decay models generally rely on use of a partial state density (PSD) formula which is generated using an assumed equidistantly spaced set of single particle levels. This is a reasonable assumption for mid-shell nuclei; however it has been demonstrated that quite large errors may be introduced by making the equidistant spacing assumption for nuclei which have neutron or proton numbers near or at major shell closures. This work reviews the simple qualitative considerations of those deviations expected for near closed shell nuclei, these expectations are compared with experimental results, and steps are taken to implement use of partial state densities calculated with more realistic sets of single particle levels in precompound decay calculations. This is done for the case of Zr targets. 13 refs., 14 figs.

Since 1958, CO{sub 2} concentrations at Mauna Loa Observatory have been obtained using a nondispersive, dual detector, infrared gas analyzer. Air samples are obtained from air intakes at the top of four 7m towers and one 27m tower. Those involved in the monitoring project have attempted to improving sampling techniques, reduce possible contamination sources, and adjust data to represent uncontaminated, true conditions throughout the twenty-eight year sampling period. The gas analyzer is calibrated by standardized CO{sub 2}-in-nitrogen reference gases twice daily. Flask samples are taken twice a month for comparison to the data recorded using the infrared gas analyzer. Data are scrutinized daily for possible contamination and archived on magnetic tape for further scrutiny and adjustment. Daily, monthly, and annual averages are computed for the Mauna Loa data after deletion of contaminated samples and readjustment of the data. These averages have shown a steady rise in annual average concentration from 316 parts per million by volume (ppmv) in 1959 to 346 ppmv in 1986.

Based on BNL's study it was concluded that there are low-level radioactive wastes (LLWs) which contain chemically hazardous components. Scintillation liquids may be considered an EPA listed hazardous waste and are, therefore, potential mixed wastes. Since November 1985, no operating LLW disposal site will accept these wastes for disposal. Unless such wastes contain de minimis quantities of radionuclides, they cannot be disposed of at an EPA permitted site. Currently generators of liquid scintillation wastes can ship de minimis wastes to be burned at commercial facilities. Oil wastes may also eventually be an EPA listed waste and thus will have to be considered a potential radioactive mixed waste unless NRC establishes de minimis levels of radionuclides below which oils can be managed as hazardous wastes. Regarding wastes containing lead metal there is some question as to the extent of the hazard posed by lead disposed in a LLW burial trench. Chromium-containing wastes would have to be tested to determine whether they are potential mixed wastes. There may be other wastes that are mixed wastes; the responsibility for determining this rests with the waste generator. While management options for handling potential mixed wastes are available, there is limited regulatory guidance for generators. …

A type of Three Mile Island Unit 2 (TMI-2) defueling canister, called a ''knockout'' canister, was subjected to a series of drop tests at the Oak Ridge National Laboratory's Drop Test Facility. These tests were designed to confirm the structural integrity of internal fixed neutron poisons in support of a request for NRC licensing of this type of canister for the shipment of TMI-2 reactor fuel debris to the Idaho National Engineering Laboratory (INEL) for the Core Examination R and D Program. Work conducted at the Oak Ridge National Laboratory included (1) precise physical measurements of the internal poison rod configuration before assembly, (2) canister assembly and welding, (3) nondestructive examination (an initial hydrostatic pressure test and an x-ray profile of the internals before and after each drop test), (4) addition of a simulated fuel load, (5) instrumentation of the canister for each drop test, (6) fabrication of a cask simulation vessel with a developed and tested foam impact limiter, (7) use of refrigeration facilities to cool the canister to well below freezing prior to three of the drops, (8) recording the drop test with still, high-speed, and normal-speed photography, (9) recording the accelerometer measurements during impact, (10) disassembly and …

Important topics concerning Muon Catalyzed Fusion were investigated in experiments at the Swiss Institute for Nuclear Research (SIN), including transient and steady state rates for the main d..mu..t cycle as well as detailed information about the competing d..mu..d and t..mu..t fusion branches. The basic kinetic parameters were determined and striking features of the resonant d..mu..t formation process were revealed (density effect, epithermal behavior). DT sticking was measured with independent techniques, i.e., detection of fusion neutrons as well as ..mu..He x-rays after fusion. Fusion yields per muon of 113 +- 10 were observed at liquid conditions, yields exceeding 200 are anticipated for optimal conditions from our results. 43 refs., 8 figs., 3 tabs.