The HELIOS (High Energy Lepton and Ion Spectrometer) experiment, installed at the CERN Super Proton Synchrotron, proposes to examine in detail the physical properties of a state of high energy created in nuclei by ultra-relativistic nucleus-nucleus collisions. It is generally believed that, at high densities or temperatures, a phase transition to a plasma of quark and gluons will occur. The dynamic of the expansion of such a plasma and its subsequent condensation into a hadron gas should markedly affect the composition and momentum distribution of the emerging particles and photons. The HELIOS experimental setup therefore combines 4..pi.. calorimetric coverage with measurements of inclusive particle spectra, two particle correlations, low and high mass lepton pairs and photons. The emphasis is placed on transverse energy flow (E/sub /tau//) measurements with good energy resolution, and the ability to trigger the acquisition of data in a variety of E/sub /tau// ranges, thereby selecting the impact parameter or the violence of the collisions. This short note presents HELIOS results, for the most part still preliminary, on /sup 16/O--nucleus collisions at the incident energies of 60 and 200 GeV per nucleon. The E /sub /tau// distributions from Al, Ag and W targets are discussed and compared …

A comprehensive test program was conducted on the FFTF 8-in. Secondary Isolation Valve (SIV) to qualify its use in the FFTF system. The tests were performed in the Small Components Test Loop/Piping and Valve Test Insert (SCTL/PVTI) facility at the Liquid Metal Engineering Center (LMEC) in accordance with Westinghouse Test Request WDTRS 26.05. Physical inspections were conducted at the conclusion of sodium testing and following an alcohol cleaning process. Results of the investigation indicate that the valve is suitable for use as an FFTF plant spare.

A model for printed circuit boards which can be used to predict the probability that a router will successfully make a connection is presented. The model reflects certain characteristics of the circuit board that is being routed and the model incrementally changes as the board is routed. Routing procedures typically have certain parameters which influence selection of the set of paths that are explored, and determine the order of exploration. These parameters obviously influence the probability that a particular connection can be made. These parameters may also be used to formulate a model of the behavior of a particular routing procedure.

Designing an adaptive optics (AO) system for extremely large telescopes (ELT's) will present new optical engineering challenges. Several of these challenges are addressed in this work, including first-order design of multi-conjugate adaptive optics (MCAO) systems, pyramid wavefront sensors (PWFS's), and laser guide star (LGS) spot elongation. MCAO systems need to be designed in consideration of various constraints, including deformable mirror size and correction height. The y,{bar y} method of first-order optical design is a graphical technique that uses a plot with marginal and chief ray heights as coordinates; the optical system is represented as a segmented line. This method is shown to be a powerful tool in designing MCAO systems. From these analyses, important conclusions about configurations are derived. PWFS's, which offer an alternative to Shack-Hartmann (SH) wavefront sensors (WFS's), are envisioned as the workhorse of layer-oriented adaptive optics. Current approaches use a 4-faceted glass pyramid to create a WFS analogous to a quad-cell SH WFS. PWFS's and SH WFS's are compared and some newly-considered similarities and PWFS advantages are presented. Techniques to extend PWFS's are offered: First, PWFS's can be extended to more pixels in the image by tiling pyramids contiguously. Second, pyramids, which are difficult to manufacture, can …

The corrosion resistance of Alloy 22 (UNS No.: N06022) was studied in simulated ground water of different pH values and ionic contents at various temperatures. Potentiodynamic polarization techniques were used to study the electrochemical behavior and measure the critical potentials in the various systems. Alloy 22 was found to be resistant to localized corrosion in the simulated ground waters tested.

Coherent scattering is a flavor-blind, high-rate, as yet undetected neutrino interaction predicted by the Standard Model. We propose to use a compact (kg-scale), two-phase (liquid-gas) argon ionization detector to measure coherent neutrino scattering off nuclei. In our approach, neutrino-induced nuclear recoils in the liquid produce a weak ionization signal, which is transported into a gas under the influence of an electric field, amplified via electroluminescence, and detected by phototubes or avalanche diodes. This paper describes the features of the detector, and estimates signal and background rates for a reactor neutrino source. Relatively compact detectors of this type, capable of detecting coherent scattering, offer a new approach to flavor-blind detection of man-made and astronomical neutrinos, and may allow development of compact neutrino detectors capable of nonintrusive real-time monitoring of fissile material in reactors.

When the field of modern publishing was on a collision course with telecommunications, publishing organizations had to come up to speed in fields that were, heretofore, completely foreign and technologically forbidding to them. For generations, the technology of publishing centered on offset lithography, typesetting, and photography--fields that saw evolutionary and incremental change from the time of Guttenberg. But publishing now includes making information available over the World Wide Web--Internet publishing--with its ever-accelerating rate of technological change and dependence on computers and networks. Clearly, we need a methodology to help anyone in the field of Internet publishing plan for the future, and there is a well-known, well-tested technique for just this purpose--Scenario Planning. Scenario Planning is an excellent tool to help organizations make better decisions in the present based on what they identify as possible and plausible scenarios of the future. Never was decision making more difficult or more crucial than during the years of this study, 1996-1999. This thesis takes the position that, by applying Scenario Planning, the Technical Information Department at LLNL, a large government laboratory (and organizations similar to it), could be confident that moving into the telecommunications business of Internet publishing stood a very good chance of …

Transport mirrors within the National Ignition Facility, a 192-beam 4-MJ fusion laser at 1053 nm, will be exposed to backscattered light from plasmas created from fusion targets and backlighters. This backscattered light covers the UV and visible spectrum from 351-600 nm. The transport mirror BK7 substrates will be intentionally solarized to absorb >95% of the backscattered light to prevent damage to the metallic mechanical support hardware. Solarization has minimal impact on the 351- and 1053-nm laser-induced damage threshold or the reflected wavefront of the multilayer hafnia silica coating. Radiation sources of various energies were examined for BK7 darkening efficiency within the UV and visible region with 1.1 MeV gamma rays from a Cobalt 60 source ultimately being selected. Finally, bleaching rates were measured at elevated temperatures to generate a model for predicting the lifetime at ambient conditions (20 C), before solarized BK7 substrates exceed 5% transmission in the UV and visible region. Over a 30-mm thickness, BK7 glass will bleach in 10 years to 5% transmission at 600 nm, the most transmissive wavelengths over the 351-600 nm regions.

This manuscript is meant to give a short summary of the advantages of high order schemes and suitable test problems which can properly illustrate these advantages.

The objective of this study was to measure the leaching and adsorption characteristics of uranium in six near-surface sediment samples collected from the 300 Area of the Hanford Site. Scanning electron micrographs of the samples showed that the uranium contamination in the sediments is most likely present as co-precipitates and/or discrete uranium particles. Molecular probe techniques also confirm the presence of crystalline discrete uranium bearing phases. In all cases, the uranium is present as oxidized uranium (uranyl [U(VI)]). Results from the column leach tests showed that uranium leaching did not follow a constant solubility paradigm. Four of the five contaminated sediments showed a large near instantaneous release of a few percent of the total uranium followed by a slower continual release. Steady-state uranium leachate concentrations were never measured and leaching characteristics and trends were not consistent among the samples. Dissolution kinetics were slow, and the measured leach curves most likely represent a slow kinetically controlled desorption or dissolution paradigm. Batch adsorption experiments were performed to investigate the effect of pH and uranium and carbonate solution concentrations on uranium adsorption onto the uncontaminated sediment. Uranium adsorption Kd values ranged from 0 to > 100 ml/g depending on which solution parameter was …

Solute effect on the creep resistance of two-phase lamellar TiAl with an ultrafine microstructure creep-deformed in a low-stress (LS) creep regime [where a linear creep behavior was observed] has been investigated. The resulted deformation substructure and in-situ TEM experiment revealed that interface sliding by the motion of pre-existing interfacial dislocations is the predominant deformation mechanism in LS creep regime. Solute segregation at lamellar interfaces and interfacial precipitation caused by the solute segregation result in a beneficial effect on the creep resistance of ultrafine lamellar TiAl in LS creep regime.

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Optical parametric amplification is an established broadband amplification technology based on a second-order nonlinear process of difference-frequency generation (DFG). When used in chirped pulse amplification (CPA), the technology has been termed optical parametric chirped pulse amplification (OPCPA). OPCPA holds a potential for producing unprecedented levels of peak and average power in optical pulses through its scalable ultrashort pulse amplification capability and the absence of quantum defect, respectively. The theory of three-wave parametric interactions is presented, followed by a description of the numerical model developed for nanosecond pulses. Spectral, temperature and angular characteristics of OPCPA are calculated, with an estimate of pulse contrast. An OPCPA system centered at 1054 nm, based on a commercial tabletop Q-switched pump laser, was developed as the front end for a large Nd-glass petawatt-class short-pulse laser. The system does not utilize electro-optic modulators or multi-pass amplification. The obtained overall 6% efficiency is the highest to date in OPCPA that uses a tabletop commercial pump laser. The first compression of pulses amplified in highly nondegenerate OPCPA is reported, with the obtained pulse width of 60 fs. This represents the shortest pulse to date produced in OPCPA. Optical parametric amplification in {beta}-barium borate was combined with laser amplification …

The reference letter dated October 4, 1956, requested that they review the possibilities of a crippling accident in 232-H and the measures which might be taken to minimize the loss in tritium production associated with such an accident be reviewed. These subjects have been reviewed in considerable detail and the authors feel that the chances of a crippling accident are quite remote. In arriving at this conclusion, the entire process was reviewed and the following three incidents were selected as having the most serious potential. (1) a tank containing tritium at subatmospheric pressure develops a leak and becomes contaminated with air equalized to atmospheric pressure; (2) a flange is removed inadvertently or a nozzle breaks on a tank containing tritium at 15 psig; (3) the water jacket on the extraction furnace ruptures internally, particularly when the charge is molten. From the foregoing, it may be concluded that a serious accident in one line is unlikely to shut down the other from the standpoint of either physical damage or serious contamination. It should be recognized that some outage, perhaps a matter of days or even weeks, could result while safety of operation is assured. Insofar as procurement of long delivery equipment …

The capsule targets for ignition experiments at the National Ignition Facility must meet very exacting requirements. Primary among them is an extremely high degree of symmetry at all length scales for the 2-mm-diameter 150-{micro}m-walled capsule. At LLNL work is in progress to produce both polyimide and sputtered beryllium targets that meet these specifications. Both of these targets require a thin-walled spherical-shell plastic mandrel upon which the beryllium or polyimide ablator is deposited. In this paper we report on recent progress in developing NIF capsules that meet the demanding design requirements.

We are investigating the evaporation of pore water representative of the designated high-level-nuclear-waste repository at Yucca Mountain, NV to predict the range of brine compositions that may contact waste containers. These brines could form potentially corrosive thin films on the containers and impact their long-term integrity. Here we report the geochemistry of a relatively complex synthetic Topopah Spring Tuff pore water that was progressively evaporated in a series of experiments. The experiments were conducted in a closed vessel, heated to 95 C, and purged with atmospheric CO{sub 2}. Aqueous samples of the evaporating solution were taken and analyzed to determine the evolving water chemistry, and the final solid precipitate was analyzed by X-ray diffraction. The synthetic Topopah Spring Tuff water evolved towards a complex brine that contains about 3 mol% SO{sub 4}, and 2 mol% Ca, 3 mol% K, 5 mol% NO{sub 3}, 40 mol% Cl, and 47 mol% Na. Trends in the solution data and identification of CaSO{sub 4} solids (anhydrite and bassanite) suggest that fluorite, carbonate, sulfate, and Mg-silicate precipitation minimize the corrosion potential of ''sulfate type pore water'' by removing F, Ca, and Mg during the early stages of evaporation.

Processing of multiple types of irradiated fuel elements in Purex has been proposed to the Atomic Energy Commission as a means of realizing significant savings in overall CPD operating costs for weapons programs and permitting release of the Redox plant for non-weapons programs. The process and equipment requirements for implementing a multipurpose operations program have been under study in both plant and laboratory programs for processing slightly enriched Zircalloy-clad uranium metal fuels and plutonium-aluminum metal alloy fuels. The purpose of this document is to present the results of a preliminary engineering study on the processing of irradiated NPR, E-Metal, D-Metal, and normal uranium fuels and PRIR and Pu-240 plutonium-aluminum alloy fuels and to provide process flowsheets as the basis for scope design of a project for increasing processing flexibility at Purex.

For flows that contain significant structure, high order schemes offer large advantages over low order schemes. Fundamentally, the reason comes from the truncation error of the differencing operators. If one examines carefully the expression for the truncation error, one will see that for a fixed computational cost that the error can be made much smaller by increasing the numerical order than by increasing the number of grid points. One can readily derive the following expression which holds for systems dominated by hyperbolic effects and advanced explicitly in time: flops = const * p{sup 2} * k{sup (d+1)(p+1)/p}/E{sup (d+1)/p} where flops denotes floating point operations, p denotes numerical order, d denotes spatial dimension, where E denotes the truncation error of the difference operator, and where k denotes the Fourier wavenumber. For flows that contain structure, such as turbulent flows or any calculation where, say, vortices are present, there will be significant energy in the high values of k. Thus, one can see that the rate of growth of the flops is very different for different values of p. Further, the constant in front of the expression is also very different. With a low order scheme, one quickly reaches the limit of …

The Winter Fuels Report is intended to provide concise, timely information to the industry, the press, policymakers, consumers, analysts, and State and local governments on the following topics: Distillate fuel oil net production, imports and stocks on a US level and for all Petroleum Administration for Defense Districts (PADD) and product supplied on a US level; propane net production, imports and stocks on a US level and for PADD`s I, II, and III; natural gas supply and disposition and underground storage for the US and consumption for all PADD`S; as well as selected National average prices; residential and wholesale pricing data for heating oil and propane for those States participating in the joint Energy Information Administration (EIA)/State Heating Oil and Propane Program; crude oil and petroleum price comparisons for the US and selected cities; and a 6--10 Day, 30-Day, and 90-Day outlook for temperature and precipitation and US total heating degree-days by city.

There are numerous conditions of the generation system that may ultimately develop into system states affecting system reliability and security. Such generation system conditions should also be considered when evaluating the potential impacts on system operations. The following five issues have been identified to impact system reliability and security to the greatest extent: transmission access/retail wheeling; non-utility generators and independent power producers; integration of dispersed storage and generation into utility distribution systems; EMF and right-of-way limitations; Clean Air Act Amendments. Strictly speaking, some issues are interrelated and one issue cannot be completely dissociated from the others. However, this report addresses individual issues separately in order to determine all major aspects of bulk power system operations affected by each issue. The impacts of the five issues on power system reliability and security are summarized. This report examines the five critical issues that the US electric utility industry will be facing over the next decade. The investigation of their impacts on utility industry will be facing over the next decade. The investigation of their impacts on utility system reliability and security is limited to the system operation viewpoint. Those five issues will undoubtedly influence various planning aspects of the bulk transmission system. …

Return can be increased on the order of $1000 to $2000 per calendar day at each K Reactor if the goal exposure for natural I & E slugs is reduced from 800 to 700 MWD/T. This gain is predicated on primarily a decrease in rupture losses. The recommended goal is a straight line on a linear graph of exposure in MWD/T versus maximum tube power in kw per tube, passing through the following two points: (850 kw/tube, 900 MWD/T); (1400 kw/tube; 490 MWD/T). In addition, I & E natural uranium charges running below 850 kw, if any, should be discharged not higher than 900 MWD/T. At a maximum tube power of 1300 kw, the recommended goal will give a weighted average exposure of about 700 MWD/T. Power at which a tube operates should be determined as recommended in HW-57937, ``Goal Exposure for Enriched I & E Material at the C and K Reactors.`` These are interim recommendations. We expect to recommend some changes in the goal, for reasons explained below. The recommended goal was calculated on the IBM-650, using an equation for return. The equation included, we believe, proper allowance for all but two factors. Principle affecting factors were included.

The accomplishments of the work done under DOE sponsorship are summarized in the list of publications at the end of this narrative. Here we give a brief description of the nature and the significance of the accomplishments. The activity can be roughly subdivided into three parts: studies of surface alloys, studies of epitaxial ultra-thin films, and studies of electron band structure of metals. The list reflects the developments of particular areas of research and the phasing out of others as this was suggested by the interest in, and the success of, specific experimental projects.

The International Petroleum Statistics Report presents data on international oil production, demand, imports, exports, and stocks. The report has four sections. Section 1 contains time series data on world oil production, and on oil demand and stocks in the Organization for Economic Cooperation and Development (OECD). This section contains annual data beginning in 1985, and monthly data for the most recent two years. Section 2 presents an oil supply/demand balance for world. This balance is presented in quarterly intervals for the most recent two years. Section 3 presents data on oil imports by OECD countries. This section contains annual data for the most recent year, quarterly data for the most recent twelve months. Section 4 presents annual time series data on world oil production and oil stocks, demand, and trade in OECD countries World oil production and OECD demand data are for the years 1970 through 1992; OECD stocks from 1973 through 1992: and OECD trade from 1982 through 1992.

The mixing necessary to explain the ``Fe`` line widths and possibly the observed red shifts of 1987A is explained in terms of large scale, entropy conserving, up and down flows (calculated with a smooth particle 2-D code) taking place between the neutron star and the explosion shock wave due to the gravity and neutrino deposition. Depending upon conditions of entropy and mass flux further accretion takes place in single events, similar to relaxation oscillator, fed by the downward flows of low entropy matter. The shock, in turn, is driven by the upflow of the buoyant high entropy bubbles. Some accretion events will reach a temperature high enough to create a neutrino ``fireball,`` a region hot enough, 11 Mev, so as to be partially opaque to its own (neutrino) radiation. The continuing neutrino deposition drives the explosion shock until the entropy of matter flowing downwards onto the neutron star is high enough to prevent further accretion. This process should result in a robust supernova explosion.