An electronics package for a small, battery-operated, self-contained, neutron coincidence counter based on a portable shift-register (PSR) has been developed. The counter was developed for applications not adequately addressed by commercial packages, including in-plant measurements to demonstrate compliance with regulations (domestic and international), in-plant process control, and in-field measurements (environmental monitoring or safeguards). Our package's features, which address these applications, include the following: Small size for portability and ease of installation;battery or mains operation; a built-in battery to power the unit and a typical detector such as a small sample counter, for over 6 h if power lines are bad or noisy, if there is a temporary absence of power, or if portability is desired; complete support, including bias, for standard neutron detectors; a powerful communications package to easily facilitate robust external control over a serial port; and a C-library to simplify creating external control programs in computers or other controllers. Whereas the PSR specifically addresses the applications mentioned above, it also performs all the measurements made by previous electronics packages for neutron coincidence counters developed at Los Alamos and commercialized. The PSR electronics package, exclusive of carrying handle, is 8 by 10 by 20 cm; it contains the circuit …

It is generally believed that many properties of solid interfaces are ultimately determined by their structure and composition at the atomic level. We report here on work in two areas of grain boundary (GB) research in which structure-property correlations have been investigated recently. HREM observations in connection with computer modeling of GBs in fcc metals have given considerable insight into correlations between GB energy and atomic-scale GB structure. Efforts to understand and possibly control the supercurrent transport behavior across GBs in high-temperature superconductors require the combination of microstructure characterizations with investigations of electric transport properties. In both areas considerable progress is being made and has already lead to important insights concerning interfacial properties.

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The National Storage Laboratory (NSL) was organized to investigate, demonstrate, and commercialize high-performance hardware and software storage technologies that promise to remove network computing bottlenecks and provide critically needed new storage systems functionality. This paper briefly outlines the goals, collaboration and current status of the NSL.

A new 250 GHz, two-frequency microwave interferometer system has been developed to diagnose divertor plasmas on DIII-D. This diagnostic will measure the line-averaged density across both the inner and outer, lower divertor legs. With a cut-off density of over 7 {times} 10{sup 14} cm{sup {minus}3}, temporal measurements of ELMs, MARFs and plasma detachment are expected. The outer leg system will use a double pass method while the inner leg system will be single pass. Two special 3D carbon composite tiles are used, one to protect the microwave antennas mounted directly under the strike point and the other as the outer leg reflecting surface. Performance, design constraints, and the thermalmechanical design of the 3D carbon composite tiles are discussed.

Backscattering experiments at microwave frequencies were conducted off the west coast of Scotland in the summer of 1991. Using a dual-polarization, 8-frequency X-band coherent scatterometer mounted on the bow of a boat, we measured time-resolved backscattering from ocean waves at a range of grazing angles from 10{degrees} to 70{degrees}. From the grazing-angle-dependent signals and their Doppler spectra, we differentiate Bragg scattering from non-Bragg scattering and resolve ``peak separation`` between the vertical and horizontal polarizations. We observe instances of ``super`` events, i.e., instances when the horizontal polarization return power equals or exceeds the vertical polarization power. We find that ``super`` events occur not only at low grazing angles but at any grazing angle for against-wind viewing directions. Statistics for such occurrences as a function of grazing angle are obtained. We study the coherence properties of scatterers and find strong evidence that at low grazing angles, lifetime-dominated, non-Bragg scattering contributes noticeably to returns of both polarizations, but is dominant in providing returns for the horizontal polarization. We examine ``spiking`` events and find that they can be related to, but need not be limited to, breaking wave events. By comparing the data of against-wind runs with cross-wind and circle runs, we obtain wind-direction …

This document contains information about lessons learned from the decontamination and decommissioning of the Feed Materials Production Center in Fernald Ohio. The information relates to Plant 7 which was constructed to house processes for the reduction of uranium hexafluoride to uranium tetrafluoride. Topics discussed include: washdown, lockdown, asbestos removal, and bidding for dismantlement projects.

These proceedings were generated from a series of presentations made at the Neural Network Workshop for the Hanford Community. The abstracts and viewgraphs of each presentation are reproduced in these proceedings. This workshop was sponsored by the Computing and Information Sciences Department in the Molecular Science Research Center (MSRC) at the Pacific Northwest Laboratory (PNL). Artificial neural networks constitute a new information processing technology that is destined within the next few years, to provide the world with a vast array of new products. A major reason for this is that artificial neural networks are able to provide solutions to a wide variety of complex problems in a much simpler fashion than is possible using existing techniques. In recognition of these capabilities, many scientists and engineers are exploring the potential application of this new technology to their fields of study. An artificial neural network (ANN) can be a software simulation, an electronic circuit, optical system, or even an electro-chemical system designed to emulate some of the brain`s rudimentary structure as well as some of the learning processes that are believed to take place in the brain. For a very wide range of applications in science, engineering, and information technology, ANNs offer …

Realistic multidisciplinary design optimization (MDO) of advanced aircraft using state-of-the-art computers is an extremely challenging problem from both the physical modelling and computer science points of view. In order to produce an efficient aircraft design, many trade-offs must be made among the various physical design variables. Similarly, in order to produce an efficient design scheme, many trade-offs must be made among the various MDO implementation options. In this paper, we examine the effects of vectorization and coarse-grained parallelization on the SD calculation using a representative example taken from a transonic transport design problem.

The U.S. Department of Energy (DOE) Transportation Management Division (TMD) is responsible for managing its various programs via a diverse combination of Government-Owned/Contractor-Operated facilities. TMD is seeking to update it automation capabilities in capturing and processing DOE transportation information. TMD`s Transportation Information Network (TIN) is an attempt to bring together transportation management, shipment tracking, research activities and software products in various stages of development. The TMD`s Automated Transportation Management System (ATMS) proposes to assist the DOE and its contractors in performing their daily transportation management activities and to assist the DOE Environmental Management Division in its waste management responsibilities throughout the DOE complex. The ATMS system will center about the storage, handling and documentation involved in the environmental clean-up of DOE sites. Waste shipments will be moved to approved Treatment, Storage and Disposal (TSD) facilities and/or nuclear material repositories. An additional investment in shipping samples to analytical laboratories also involves packaging and documentation according to all applicable U.S. Department of Transportation (DOT) or International Air Transport Association (IATA) regulations. The most immediate goal of effectively managing DOE transportation management functions during the 1990`s is an increase in automation capabilities of the DOE and its contractors. Subject-matter experts from various DOE …

In the effort to evaluate boron-rich coatings as plasma facing surfaces in fusion devices, a new process for applying boron carbide (B{sub 4}C) coatings to graphite was developed. The process entails eutectic melting of the carbon (C) substrate surface with a precursor layer of B{sub 4}C particles. Adherent coatings were achieved which consisted of two layers: a surface layer and a graded penetration zone in the outer portion of the substrate. The surface-layer microstructure was multiphase and ranged from reaction-sintered structures of sintered B{sub 4}C particles in an eutectic-formed matrix to that of hypereutectic carbon particles in a B{sub 4}C-C eutectic matrix. Because of high surface energy, the coating generally developed a nonuniform thickness. Quantitative evaluations of the coating were performed with limiters in the TEXTOR fusion device and with coupons in electron beam tests. Test results revealed the following: good adherence of the coating even after remelting; and, during remelting, diagnostics detected a corresponding interaction of boron with the plasma.

Packaging of integrated optic modulators can be simplified if the electrodes are 50 ohms impedance. Recently built X-cut lithium niobate velocity matched modulators have a 50 ohm impedance. The interconnection of the modulators to external connectors by on-chip tapers is critical to there performance at frequencies in the 23 to 50 Ghz frequency range. The attachment of fibers to the modulators is being enhanced with work on a robotic machine that uses a combination of machine vision and active alignment to both coarse and fine position the fiber to the waveguide. The design goal is to have each fiber attached in under 2 minutes.

The authors have developed a general technique which combines the temporal resolution of ultrafast laser spectroscopy with the spatial resolution of scanned probe microscopy (SPM). Using this technique with scanning tunneling microscopy (STM), they have obtained simultaneous 2 ps time resolution and 50 {angstrom} spatial resolution. This improves the time resolution currently attainable with STM by nine orders of magnitude. The potential of this powerful technique for studying ultrafast dynamical phenomena on surfaces with atomic resolution is discussed.

The Collider Detector at Fermilab is upgrading its end plug calorimeter from a gas detector system to one using scintillating tiles and wavelength shifting fibers. This tile-fiber calorimeter will be read out through 1,824 photomultiplier tubes. The performance requirements of the calorimeter require that the PMTs have good response to light in the 500 nm region, provide adequate amplification for signals from minimum ionizing particles yet provide linear response for peak anode currents up to 25 mA at a gain of 50,000, and fit into the restricted space at the rear of the plugs. This paper will describe the evaluation process used to determine the adequacy of the commercially available PMTs which appeared to meet these performance requirements.

The reactions {sup 129}Xe + {sup 27}Al, {sup nat}Cu, {sup 89}Y, {sup 165}Ho and {sup 197}Au at 60 MeV/nucleon were investigated with the combination of a high-resolution forward array of Si-Si-plastic telescopes and a high-efficiency phoswich ball. The projectile-like primary source was reconstructed. Its parallel velocity component is strongly correlated with the observed multiplicity and hence with dissipation. At high multiplicity, large fragments still show a projectile-like and target-like components in their parallel velocity distributions. A further sub-division of highly dissipative events into binary-like and non binary-like subclasses has been performed by applying an additional experimental selection of the orientation of the event in momentum space.

The power requirements for a satellite power beaming laser system depend upon the diameter of the beam director, the performance of the adaptive optics system, and the mission requirements. For an 8 meter beam director and overall Strehl ratio of 50%, a 30 kW laser at 850 nm can deliver an equivalent solar flux to a satellite at geostationary orbit. Advances in Diode Pumped Solid State Lasers (DPSSL) have brought these small, efficient and reliable devices to high average power and they should be considered for satellite power beaming applications. Two solid state systems are described: a diode pumped Alexandrite and diode pumped Thulium doped YAG. Both can deliver high average power at 850 nm in a single aperture.

Sodium dichromate has been identified as a contaminant of concern at several waste sites on the Hanford Site. Although chromium standards for soil are typically stated in terms of total chrome, much of the toxicity and carcinogenicity are attributed to the hexavalent state, which typically exists as a relatively mobile anion. Investigation and removal of crushed drums potentially containing residual sodium dichromate required a field test for hexavalent chromium to support characterization and remediation activities. Previous experience with a commercially available field test kit had been unsuccessful. This stimulated an effort to determine potential sources of error in the field test and led to a number of modifications that significantly improved the reliability of the test.

The objective of the planned research in advanced tokamak development on DIII-D at General Atomics, San Diego, USA. is to establish improved tokamak operation through significant improvements in the stability factor, confinement quality, and bootstrap current fraction using localized radio frequency (rf) current profile control, rf and neutral beam heating for pressure profile control, as well as control of plasma rotation and optimization of the plasma boundary conditions. Recent research results in H-mode confinement, modifications of current profiles to achieve higher confinement and higher {beta}, a new regime of improved confinement (VH-mode), and rf noninductive current drive are encouraging. In this talk, arguments will be presented supporting the need for improved performance in tokamak reactors. Experimentally observed advanced performance regimes on DIII-D will be discussed. Confinement improvement up to H = 4, where H is the ratio of energy confinement time to the ITER89-P scaling H{triple_bond} {Tau}{sub E}/{Tau}{sub E-ITER89-P}, has been achieved. In other discharges {beta}{sub N} = {beta}/(I/aB),[%-m{center_dot}{Tau}/MA] {approx_gt} 6 has been obtained. These values have so far been achieved transiently and independently. Techniques, will be described which can extend the high performance to quasi-steady-state and sustain the high H and {beta}{sub N} values simultaneously. Two high performance regimes, …

Segregation of cations based on size is observed in samples of zeolite-A loaded with simulated radioactive-waste ({approximately}5 wt.% Li, K, Cs and Ba, 1 wt.% Sr and Y, <1 wt.% Na) prepared from chloride salts. In contrast to traditional Na zeolite-A, for which all 8-ring access super ({alpha}) cages are identical and situated on a simple face-centered-cubic lattice, these simulated rad-waste mixtures contain two types of {alpha}-cages situated on a NaCl-like lattice. The long range ordering of extra-framework ions is propagated by severe distortion of frame work oxygens due to strong coordination with Li.

The Hanford Site began operations in 1943 as one of the sites for plutonium production associated with the Manhattan Project. It has been used, in part, for nuclear reactor operation, reprocessing of spent fuel, and management of radioactive waste. The Hanford Site covers approximately 1,434 km{sup 2} (560 mi{sup 2}2) in southeastern Washington State. The subject of this paper, the 618-9 Burial Ground, is located on the Hanford Site approximately 1.6 km (1 mi) west of the Columbia River, and a few miles north of Richland, Washington. Throughout Hanford Site history, prior to legislation regarding disposal of chemical waste products, some chemical waste byproducts were disposed ,ia burial in trenches. One such trench was the 618-9 Burial Ground. This burial ground was suspected to contain approximately 19,000 L (5,000 gal) of uranium-contaminated organic solvent, disposed in standard 55-gal (208-L) metal drums. The waste was produced from research and development activities related to fuel reprocessing.

The Fernald Environmental Management Project (FEMP), formerly the Feed Materials Production Center (FMPC), is a Department of Energy (DOE) site which produced high-quality uranium for military defense beginning in 1951. Production at the FEMP was halted in July 1989. Later that year, the facility was placed on the National Priorities List (NPL). The DOE is currently conducting a Remedial Investigation/Feasibility Study (RI/FS) and other response actions under the Amended Consent Agreement between the US Environmental Protection Agency (USEPA) and the DOE.

Performance simulation has been carried out for several LiBr/H2O triple-effect cycles using the Absorption Simulation Model (ABSIM) . The systems investigated include the three-condenser-three-desorber (3C3D) cycle, forming an extension of the conventional double-effect cycle; and two cycles which additionally recover heat from the hot condensate leaving the highest temperature condenser by adding the heat to the lowest temperature desorber. These latter two cycles are called Double Condenser Coupled (DCC) cycles since each uses heat recovered from the highest temperature refrigerant to heat both the middle temperature desorber (heat of condensation) and the lowest temperature desorber (by further subcooling the condensed refrigerant), hence the ``double-coupling``. ABSIM, a modular computer code for simulation of absorption systems, was used to investigate the performances of each of the cycles and compare them on an equivalent basis. The performance simulation was carried out over a range of operating conditions, including some investigation into the influence of varying particular design parameters. Cooling coefficients of performance ranging from 1.27 for the series-flow 3C3D to 1.73 for the parallel-flow DCC have been calculated at the design point. Relative merits of these LiBr/H20 triple-effect cycle configurations are discussed.

Ti:Sapphire (Ti:Al{sub 2}O{sub 3}) amplifier stages are typically pumped with Q-switched Nd:YAG lasers doubled to 532 nm because of good spectral overlap, short temporal width, high repetition rate (i.e., 10 Hz to > 5 kHz) and the problems associated with flashlamp pumping a material with a relatively short upper state lifetime. Limitations to this pumping method arise due to the 1 to 1.5 joule/pulse ceiling found in most commercial high rep rate Nd:YAG lasers. The availability of high quality, large aperture Ti:Sapphire rods has made the flashlamp-pumping scheme an attractive option. The excellent thermal properties of Ti:Sapphire also allows an amplifier to be operated at high repetition rates. The front end of our laser relies on Chirped Pulse Amplification (CPA) in laser pumped Ti:Sapphire to generate 55 mJ, 90 fsec pulses at a 10 Hz rate. We report the use of a flashlamp pumped Ti:Sapphire head to further amplify the output of our system, producing 90 fsec, 250 mJ pulses at 5 Hz. The excellent output spatial profile yields a near diffraction-limited 5 {mu}m spot size and peak irradiance in excess of 5 {times} 10{sup 18} W/cm{sup 2}.

We present a brief summary of recent news from LBL related to accelerator physics. This talk was given on October 29, 1993 at the 6th Advanced ICFA Beam Dynamics Workshop on the subject ``Synchro- Betraton Resonances,`` held in Funchal (Madeira, Portugal), October 24--30, 1993.