In this paper we describe the operation and testing of a string of magnets comprising a full cell of the Superconducting Super Collider (SSC). The full cell configuration composed of ten dipoles, two quadrupoles, and three spool pieces is the longest SSC magnet string ever tested. Although the tests of the full cell were undertaken after the SSC project was marked for termination, their completion was deemed necessary and useful to future efforts at other accelerator laboratories utilizing Superconducting magnets. The focus of this work is on the electrical and cryogenic performance of the string components and the quench protection system with an emphasis on solving some of the questions concerning electrical performance raised during the previous two experimental runs involving a half cell configuration.

A comparison of the neutron and photon dose rates at different locations on the outside surface of the Model AL-RB, Model FL and the AT-400A containers for a given pit load has been done in order to understand the shielding characteristics of these containers. The Model AL-R8 is not certified for transport and is only used for storage of pits, while the Model FL is a certified Type B pit transportation container. The AT-400A is being developed as a type B pit storage and transportation container. The W48, W56 and B83 pits were chosen for this study because of their encompassing features with regard to other pits presently being stored. A detailed description of the geometry and materials of these containers and of the neutron and photon emission spectra from the actinide materials present in the pit have been used in the calculations of the total dose rates. The calculations have been done using the three-dimensional, neutron-photon Monte Carlo code MCNP. The results indicate the need for a containment vessel (CV), as is found in the Model FL and AT-400A containers, in order to assure compliance with 10 CFR 71 regulations. The absence of a CV in the AL-R8 container …

We have explored the major technical and conceptual issues relating to the suitability of a diode-pumped solid state laser as a driver for an inertial fusion energy power plant. While solid state lasers have long served as the workhorse of inertial confinement fusion physics studies, the deployment of a driver possessing adequate efficiency, reliability, and repetition rate for inertial fusion energy requires the implementation of several technical innovations discussed in this article.

Calculation of river flow is important for managing reservoirs and flood forecasting. In the western United States, a complex terrain which is characterized by steep slopes and narrow valleys often cause a substantial rise of river levels in a short period during heavy precipitation events. Since flood control is one of the major tasks of reservoir operation, inaccurate predictions of precipitation and river flow may cause flooding or waste of water resources. Accurate calculations of river flow need accurate liquid water input to the river system at scales of individual watersheds. Precipitation and snowmelt are the most important natural source of water for a river. Reservoir operations significantly affect river flow in the western United States. Factors such as instantaneous soil water content, vegetation cover, terrain slope and ground water table structure are also crucial for river flow calculation. There are two types of precipitation: rain and snowfall. River flow quickly responds to rainfall while snowfall does not directly affect river flow until it melts afterwards. Therefore, these two types of precipitation must be separately provided to the river flow model for correct calculation of river flows. A large portion of snowfall is accumulated at high terrain during winter months …

This paper theoretically compares the performance of simulated annealing and evolutionary algorithms. Our main result is that under mild conditions a wide variety of evolutionary algorithms can be shown to have greater performance than simulated annealing after a sufficiently large number of function evaluations. This class of EAs includes variants of evolutionary strategie and evolutionary programming, the canonical genetic algorithm, as well as a variety of genetic algorithms that have been applied to combinatorial optimization problems. The proof of this result is based on a performance analysis of a very general class of stochastic optimization algorithms, which has implications for the performance of a variety of other optimization algorithm.

Radioactive and hazardous wastes are generated at many national laboratories, military sites, fuel fabrication and enrichment plants, reactors, and many other facilities. At all of these sites, wastes must be separated, categorized, possibly treated, and packed into containers for shipment to waste-storage or disposal sites. Prior to treatment, storage or, shipment, the containers must be characterized to determine the ultimate disposition of the contained waste. Comprehensive and accurate nondestructive evaluation (NDE) and nondestructive assay (NDA) methods can be used to characterize most waste containers in a safe and cost-effective manner without opening them. The Lawrence Livermore National Laboratory (LLNL) is investigating and developing the application of x-ray and {gamma}-ray methods to nonintrusively characterize waste containers and/or items. X-ray NDE methods are being investigated to determine whether they can be used to identify hazardous and nonconforming materials. A {gamma}-ray NDA method is used to identify the radioactive sources within a container and to accurately quantify their strength. In this paper we describe five waste characterization projects being conducted at LLNL that apply both the NDE and NDA methods and present results.

The basement membrane (BM) extracellular matrix induces differentiation and suppresses apoptosis in mammary epithelial cells, whereas cells lacking BM lose their differentiated phenotype and undergo apoptosis. Addition of purified BM components, which are known to induce {beta}-casein expression, did not prevent apoptosis, indicating that a more complex BM was necessary. A comparison of culture conditions where apoptosis would or would not occur allowed us to relate inhibition of apoptosis to a complete withdrawal from the cell cycle, which was observed only when cells acquired a three-dimensional alveolar structure in response to BM. In the absence of this morphology, both the G1 cyclin kinase inhibitor p21/WAF-I and positive proliferative signals including c-myc and cyclin Dl were expressed and the retinoblastoma protein (Rb) continued to be hyperphosphorylated. When we overexpressed either c-myc in quiescent cells or p21 when cells were still cycling, apoptosis was induced. In the absence of three-dimensional alveolar structures, mammary epithelial cells secrete a number of factors including transforming growth factor a and tenascin, which when added exogenously to quiescent cells induced expression of c-myc and interleukin-{beta}1-converting enzyme (ICE) mRNA and led to apoptosis. These experiments demonstrate that a correct tissue architecture is crucial for long-range homeostasis, suppression of …

Article on acid-base indicators and transition colours and pH ranges determined in select aqueous-organic mixed solvents.

Article discussing auditory cortex neurons and primary culture and ion channel activity in rat.

This article considers solutions to the wave equation in 3+1 spacetime dimensions whose data is compactly supported at some initial time.

Image-converter (IC) camera photography has provided spectacular images and quantitative records of liner collapse and early jet formation in shaped charges. We have extended the application of the IC camera to observations of shaped charge jet surfaces undergoing particulation. Sequential, high-resolution photographs were taken following the same 10-cm portion of jet at 2.5-{mu}s intervals. Simultaneous color rotating-mirror framing camera photographs and 450-keV flash x-ray radiographs were also taken of the same region. This combination provides a detailed record of the evolution of surface structure during jet necking and particulation. In the high-resolution photographs, individual features on the jet surfaces as small as {approximately}100 {mu}m can easily be detected and followed as they evolve over time. The jet surface structure is rough with overlapping slip dislocation lines running along the surface at 45{degree} to either side of the jet axis. This is similar to the texture that develops in long rods undergoing static tension. We discuss the implications of these images for increasing jet particulation times.

In 1997 NASA will launch the Cassini scientific probe to the planet Saturn. Electric power for this probe will be provided by Radioisotope Thermoelectric Generators thermally driven by General Purpose Heat Source modules.

The EPA has declared vitrification to be the Best Available Demonstrated Technology (BDAT) for High Level Radioactive Waste (40 CFR 268.42). Vitrification has been chosen as the method of choice for treating a number of radioactive residues and wastes in the DOE complex. Vitrification offers advantages of waste volume reduction, the ability to handle changing waste forms, and a stable, nonleachable final waste form. Microwave heating is a superior method for vitrification of radioactive wastes. Advantages of microwave heating include: (1) direct waste heating, eliminates need for electrodes, refractories and other consumables; (2) ``in-can`` processing allows for treatment of the material in its final container, (3) a mechanically simple system where the microwaves are generated away from the treatment area and transmitted to the treatment applicator by a wave guide, thus minimizing worker exposure to radiation; (4) easier equipment maintenance; and (5) a high degree of public acceptance.

The US Inertial Fusion Energy (IFE) Program is developing induction accelerator technology toward the goal of electric power production using Heavy-Ion beam-driven inertial Fusion (HIF). The recirculating induction accelerator promises driver cost reduction by repeatedly passing the beam through the same set of accelerating and focusing elements. The authors present plans for and progress, toward a small (4.5-m diameter) prototype recirculator which will accelerate K{sup +} ions through 15 laps, from 80 to 320 keV and from 2 to 8 mA. Beam confinement is effected via permanent-magnet quadrupoles; bending is via electric dipoles. Scaling laws, and extensive particle and fluid simulations of the space-charge dominated beam behavior, have been used to arrive at the design. An injector and matching section are operational. Initial experiments are investigating intense-beam transport in a linear magnetic channel; near-term plans include studies of transport around a bend. Later experiments will study, insertion/extraction and acceleration with centroid control.

An investigation of the rapid rise time of x-ray emission from targets heated by an ultrashort-pulse high-intensity optical laser was conducted for use as a pump for inner-shell photo-ionized x-ray lasing. Results of x-ray rise times from instantaneously heated Au rod targets show little benefit for using optical pulse widths less than 30 fs. Gain calculations for inner-shell photo-ionized lasing show that large gains can be obtained for pulse widths between 30 and 100 fs. Calculated spectra, using the hydrodynamic/atomic kinetics code LASNEX, from a 1 J, 65 fs FWHM pulse optical laser incident on a structured Au target gave a gain of 1 1.5 cm{sup {minus}1} in C at 45 {angstrom}.

Experimental methods to search for the ``invisible axion`` (f{sub a} {much_gt} 250 GeV) are reviewed. The report focuses on the axion-photon coupling, both for laboratory experiments as well as those looking for stellar or cosmologically produced axions. The conclusion is that while the axion-photon mixing in principle would permit laboratory axion searches which are broadband in mass, in fact no such experiment could have the sensitivity to the axion, where m{sub afa} {approx} m{sub {pi}f{pi}}. The only experiments which promise to have any chance to find the axion are the microwave cavity experiments, which presume axions to constitute our galactic halo dark matter. The conversion of axions into a monochromatic microwave signal in a resonant circuit affords the experiment the extraordinary sensitivity required to see the axion, at the expense of being narrow-band in mass, i.e. a tuning experiment. Two such efforts are underway in the world.

Accurate assessments of precipitation and surface snow budget during winter seasons are crucial for managing water resources in the western United States. This region receives most of its annual precipitation during winter months and relies on water stored in snowpack and reservoirs for water supply during dry summer seasons. Rainfall directly affects water inflow into reservoirs while snowmelt determines it during spring and summer. Precipitation and snow budget result from interactions among large-scale forcing, mesoscale processes, and surface energy balance. Interaction among these elements is highly nonlinear and includes various processes such as large-scale water vapor and temperature advection, precipitation physics, orographic forcing, turbulence, solar and terrestrial radiative transfer, and snow-albedo feedback. Hence, one need to take these processes into consideration in order to obtain accurate assessments of regional water resources over time scales longer than a season. A regional model that interactively couples atmospheric and land surface processes is a cost-effective tool for an assessment of precipitation and surface hydrology over large areas at a relatively fine resolution. Such models can include complex physical and dynamical processes involved in the interaction between the atmosphere and land surfaces. Another advantage of coupled atmosphere-land surface modeling is that simulations, when verified …

Plutonium scrap and residue represent major national and international concerns because (1) significant environmental, safety, and health (ES&H) problems have been identified with their storage; (2) all plutonium recovered from the black market in Europe has been from this category; (3) storage costs are high; and (4) safeguards are difficult. It is proposed to address these problems by conversion of plutonium scrap and residue to a CRACHIP (CRiticality, Aerosol, and CHemically Inert Plutonium) glass using the Glass Material Oxidation and Dissolution System (GMODS). CRACHIP refers to a set of requirements for plutonium storage forms that minimize ES&H concerns. The concept is several decades old. Conversion of plutonium from complex chemical mixtures and variable geometries into a certified, qualified, homogeneous CRACHIP glass creates a stable chemical form that minimizes ES&H risks, simplifies safeguards and security, provides an easy-to-store form, decreases storage costs, and allows for future disposition options. GMODS is a new process to directly convert metals, ceramics, and amorphous solids to glass; oxidize organics with the residue converted to glass; and convert chlorides to borosilicate glass and a secondary sodium chloride stream. Laboratory work has demonstrated the conversion of cerium (a plutonium surrogate), uranium (a plutonium surrogate), Zircaloy, stainless steel, …

The generation of substantial yields of H{sup {minus}} ions in a laser excited H{sub 2} gas has been reported by Pinnaduwage and Christoforu. These H{sup {minus}} yields have been attributed to (2 + 1) REMP photoexcitation processes leading to dissociative attachment of doubly-excited or superexcited states (SES), or dissociative attachment of high Rydberg product states. The new feature of these experiments is the implied large dissociative attachment rates, of order 10{sup {minus}6} cm{sup 3} sec{sup {minus}1}, values that are orders-of-magnitude larger than the dissociative attachment of the vibrationally excited levels of the ground electronic state. While these laser excitations are not directly applicable to a hydrogen negative-ion discharge, the implication of large dissociative attachment rates to the high Rydberg states may affect both the total negative-ion density and the interpretation of discharge performance. Within the discharge energetic electrons will collisionally excite the higher Rydberg states, and the relative contribution of the dissociative attachment of these states when compared with the dissociative attachment to the ground state vibrational levels, is the topic of this paper.