The success of in-situ transmission electron microscopy experimentation is often dictated by proper specimen preparation. We report here a novel technique permitting the production of cross-sectioned tensile specimens of multilayered films for in-situ deformation studies. Of primary importance in the development of this technique is the production of an electron transparent micro-gauge section using focused ion beam technology. This microgauge section predetermines the position at which plastic deformation is initiated; crack nucleation, growth and failure are then subsequently observed.

The value of energy technology R and D as an insurance investment to reduce the cost of climate change stabilization, oil price shocks, urban air pollution, and energy disruptions is estimated to be $5-8 billion/year in sum total. However, the total that is justified is actually less than this sum because some R and D is applicable to more than one risk. nevertheless, the total DOE investment in energy technology R and D (about $1.3 billion/year in FY97) seems easily justified by its insurance value alone; and, in fact, more might be warranted, particularly in the areas related to climate change and urban air pollution. This conclusion appears robust even if the private sector is assumed to be investing a comparable amount. Not counted is the value to the economy and to US competitiveness of better energy technologies that may result from the R and D; only the insurance value for reducing the cost of these four risks to society was estimated.

The transport of a high current relativistic electron beam in a stripline beam kicker is strongly dependent on the wake properties of the structure. The effect of the beam-induced fields on the steering of the beam must be determined for a prescribed trajectory within the structure. A 3-D time domain electromagnetic code is used to determine the wake fields and the resultant Lorentz force on the beam both for an ultra-relativistic electron beam moving parallel to the beamline axis as well as a beam that follows a curved trajectory through the structure. Usually in determining the wake properties of the structure, a wake impedance is found for a beam that is moving parallel to the beamline axis. However, we extend this concept to curved trajectories by calculating beam induced forces along the curved trajectory. Comparisons are made with simple transmission line models of the structure. The wake properties are used in models to transport the beam self-consistently through the structure.

Recent high-voltage breakdown experiments of periodic metallic-dielectric insulating structures have suggested several interesting high-gradient applications. One such area is the employment of high-gradient insulators in high-current, electron-beam, accelerating induction modules. For this application, the understanding of the rf characteristics of the insulator plays an important role in estimating beam-cavity interactions. In this paper, we examine the rf properties of the insulator comparing simulation results with experiment. Different insulator designs are examined to determine their rf transmission properties in gap geometries.

The transport of a high current relativistic electron beam in a stripline beam kicker is strongly dependent on the wake properties of the structure. The effect of the beam-induced fields on the steering of the beam must be determined for a prescribed trajectory within the structure. A 3-D time domain electromagnetic code is used to determine the wake fields and the resultant Lorentz force on the beam both for an ultra-relativistic electron beam moving parallel to the beamline axis as well as a beam that follows a curved trajectory through the structure. Usually in determining the wake properties of the structure, a wake impedance is found for a beam that is moving parallel to the beamline axis. However, we extend this concept to curved trajectories by calculating beam induced forces along the curved trajectory. Comparisons are made with simple transmission line models of the structure. The wake properties are used in models to transport the beam self-consistently through the structure.

Several new explosives have been developed for hard target and related applications. Materials having energy densities as high as 20 KJ/cc have been made. Mid-scale field trials have been carried out at Eglin Air Force Base. Fragmentation improvements 150% that of Tritonal have been attained.

The authors present a number of recent results obtained at the Fermilab Tevatron for b{bar b} production in p{bar p} interactions. The preliminary CDF and D0 measurements of the inclusive b-quark production cross section at {radical}s = 630 GeV are compared with the UA1 results and the next-to-leading order QCD predictions. These results are used to compute the ratio of the cross sections at 630 GeV to 1800 GeV. The CDF results on the B meson differential cross section and {Lambda}{sub b}{sup 0} baryon production and decay properties at {radical}s = 1800 GeV are also presented.

This conference explored the latest developments in low-level radioactive waste management through presentations from professionals in both the public and the private sectors and special guests. The conference included two continuing education seminars, a workshop, exhibits, and a tour of Envirocare of Utah, Inc., one of America's three commercial low-level radioactive waste depositories.

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A set of optical models for a variety of electrostatic lenses and accelerator columns has been developed for the computer code TRACE 3-D. TRACE 3-D is an envelope (matrix) code including space charge often used to model bunched beams in magnetic transport systems and radiofrequency (RF) accelerators when the effects of beam current may be important. Several new matrix models have been developed that allow the code to be used for modeling beam lines and accelerators with electrostatic components. The new models include: (1) three einzel lenses, (2) two accelerator columns, (3) three electrostatic deflectors (prisms), and (4) an electrostatic quadrupole. A prescription for setting up the initial beam appropriate to modeling 2-D (continuous) beams has also been developed. The new models for (1) are described in this paper, selected comparisons with other calculations are presented, and a beamline application is summarized.

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I present results from a next-to-leading order event generator of purely gluonic jet production. This calculation is the first step in the construction of a full next-to-leading order calculation of three jet production at hadron colliders. Several jet algorithms commonly used in experiments are implemented and their numerical stability is investigated. A numerical instability is found in the iterative cone algorithm which makes it inappropriate for use in fixed order calculations beyond leading order.

False positive detections account for a great part of the expense associated with unexploded ordnance (UXO) remediation. Presently fielded systems like pulsed electromagnetic induction systems and cesium-vapor magnetometers are able to distinguish between UXO and other metallic ground clutter only with difficulty. The discovery of giant magnetoresistance (GMR) has led to the development of a new generation of integrated-circuit magnetic sensors that are far more sensitive than previously available room-temperature-operation electronic devices. The small size of GMR sensors makes possible the construction of array detectors that can be used to image the flux emanating from a ferrous object or from a non-ferrous object with eddy currents imposed by an external coil. The purpose of a GMR-based imaging detector would be to allow the operator to easily distinguish between UXO and benign objects (like shrapnel or spent bullets) that litter formerly used defense sites (FUDS). In order to demonstrate the potential of a GMR-based imaging technology, a crude magnetic imaging system has been constructed using commercially available sensors. The ability to roughly determine the outline and disposition of magnetic objects has been demonstrated. Improvements to the system which are necessary to make it into a high-performance UXO detector are outlined.

Materials for gas turbine engines are required to meet a wide range of temperature and stress application requirements. These alloys exhibit a combination of creep resistance, creep rupture strength, yield and tensile strength over a wide temperature range, resistance to environmental attack (including oxidation, nitridation, sulphidation and carburization), fatigue and thermal fatigue resistance, metallurgical stability and useful thermal expansion characteristics. These properties are exhibited by a series of solid-solution-strengthened and precipitation-hardened nickel, iron and cobalt alloys. The properties needed to meet the turbine engine requirements have been achieved by specific alloy additions, by heat treatment and by thermal mechanical processing. A thorough understanding of the metallurgy and metallurgical processing of these materials is imperative in order to successfully fusion weld them. This same basic understanding is required for repair of a component with the added dimension of the potential effects of thermal cycling and environmental exposure the component will have endured in service. This article will explore the potential problems in joining and repair welding these materials.

The MicroTechnology Center at Lawrence Livermore National Laboratory is developing a variety of MEMS-Based analytical instrumentation systems in support of programmatic needs, along with numerous external customers. Several of the applications of interest are in the area of biochemical identification and analysis. These applications range from DNA fragment analysis and collection in support of the Human Genome Project, to detection of viruses or biological warfare agents. Each of the applications of interest has focused in micro-machined MEMS technology for reduced cost, higher throughput, and faster results. Development of these analytical instrumentation systems will have long term benefits for the medical community as well. The following describes the technologies several specific applications.

In this report is considered effects of finite crossing angle at collision point on beam dynamics in the Tevatron collider upgrade (TEV33). Impact of the beam-beam interaction on beam sizes, particles diffusion and luminosity is studied with use of computer simulations. Parameter space forr better collider performance is proposed.

It has been shown that the net space-charge forces for a dc beam with space-charge potential depression in a bend have the usual inverse energy square dependence to the first order in the beam radius a over the bend radius R. We extend the analysis to the second order in a/R and allow the beam to have a small transverse displacement. The net space-charge forces are no longer cancelled to inverse energy square factor. The non-cancelled part of self-induced magnetic forces are at the second order in a/R and independent of the beam energy. The nonlinear parts of these forces are much larger than that of the usual inverse energy square forces. Scaling laws for emittance growth caused by the curvature of the beam and a transverse beam displacement, respectively, are presented.

Degenerately-doped (> 10{sup 19} cm{sup {minus}3}) n-type In{sub x}Ga{sub 1{minus}x}As (x > 0.53) possesses a number of intriguing electrical and optical properties relevant to electro-optic devices and thermophotovoltaic devices in particular. Due to the low electron effective mass of this material and the demonstrated ability to incorporate n-type dopants into the mid-10{sup 19} cm{sup {minus}3} range, both the Moss-Burnstein bandgap shift and plasma reflection characteristics are particularly dramatic. These properties are investigated for In{sub x}Ga{sub 1{minus}x}As as a function of doping concentration, dopant type, and growth conditions. For undoped InGaAs with a nominal bandgap of 0.6 eV, doping this material to 5 {times} 10{sup 19} cm{sup {minus}3} increased the effective optical bandgap to 1.1 eV and has a plasma turn-on wavelength of 5 microns. This filter was coupled to a non-absorbing interference filter, creating a functional tandem filter for thermophotovoltaic applications.

An international standard has emerged for the first true multimedia format. Digital Versatile Disk (by its official name), you may know it as Digital Video Disks. DVD has applications in movies, music, games, information CD-ROMS, and many other areas where massive amounts of digital information is needed. Did I say massive amounts of data? Would you believe over 17 gigabytes on a single piece of plastic the size of an audio-CD? That`s the promise, at least, by the group of nine electronics manufacturers who have agreed to the format specification, and who hope to make this goal a reality by 1998. In this major agreement, which didn`t come easily, the manufacturers will combine Sony and Phillip`s one side double-layer NMCD format with Toshiba and Matsushita`s double sided Super-Density disk. By Spring of this year, they plan to market the first 4.7 gigabyte units. The question is: Will DVD take off? Some believe that read-only disks recorded with movies will be about as popular as video laser disks. They say that until the eraseable/writable DVD arrives, the consumer will most likely not buy it. Also, DVD has a good market for replacement of CD- Roms. Back in the early 80`s, the …

Twelve tests were performed at LLNL to assess loading conditions on a spent fuel casts for side drops, end drops and tipover events. The tests were performed with a 1/3-scale model concrete pad to benchmark the structural analysis code DYNA3D. The side drop and tipover test results are discussed in this report. The billet and test pad were modified with DYNA3D using material properties and techniques used in earlier tests. The peak or maximum deceleration test results were compared to the simulated analytical results. It was concluded that an analytical model based on DYNA3D code and has been adequately benchmarked for this type of application. A generic or represented cask was modified with the DYNA3D code and evaluated for ISFSI side drop and tipover events. The analytical method can be applied to similar casks to estimate impact loads on storage casks resulting from low-velocity side or tip impacts onto concrete storage pads.

A thermophotovoltaic (TPV) efficiency measurement, within a closed cavity, is an integrated test which incorporates four fundamental parameters of TPV direct energy conversion. These are: (1) the TPV devices, (2) spectral control, (3) a radiation/photon source, and (4) closed cavity geometry effects. The overall efficiency of the TPV device is controlled by the TP cell performance, the spectral control characteristics, the radiator temperature and the geometric arrangement. Controlled efficiency measurements and predictions provide valuable feedback on all four. This paper describes and compares two computer codes developed to model 16, 1 cm{sup 2} TPV cells (in a 4 x 4 configuration) in a cavity geometry. The first code, subdivides the infrared spectrum into several bands and then numerically integrates over the spectrum to provide absorbed heat flux and cell electrical output performance predictions (assuming infinite parallel plates). The second code, utilizes a Monte Carlo Photon Transport code that tracks photons, from birth at the radiation source, until they either escape or are absorbed. Absorption depends upon energy dependent reflection probabilities assigned to every geometrical surface within the cavity. The model also has the capability of tallying above and below bandgap absorptions (as a function of location) and can support various …

Baryonic matter, in the form of Machos (MAssive Compact Halo Objects), might be a significant constituent of the dark matter that dominates the Milky Way. This article describes how surveys for Machos exploit the gravitational microlens magnification of extragalactic stars. The experimental searches for this effect monitor millions of stars, in some cases every night, looking for magnification events. The early results of these surveys indicate that Machos make up a significant fraction of the dark matter in the Milky Way, and that these objects have stellar masses. Truly substellar objects do not contribute much to the total. Additionally, the relatively high event rate towards the Galactic bulge seems to require that the bulge be elongated, and massive.

As part of international agreement between the United States and Russia, a significant amount of plutonium requires disposition. One of the disposition paths is to immobilize it and dispose of it in a geological repository. The two favored immobilization forms are glass and ceramic. The plutonium, as an oxide, would be reacted with the glass or ceramic to form a homogeneousmaterial. The resulting solid product would then be encased in High-Level Waste (1-ILW)glass for the can-in-canister option. The HLW glass gives a radiation barrier to increase proliferation resistance. The glass canister would then be disposed of by geological emplacement. This paper discusses how glass meets two criteria: the condition of significant actinide volubility, and That the PuO{sub 2} feed should be incorporated into the matrix without significant amount of unreacted material.

Whether it`s photography, computer graphics, publishing, or video; each medium has a defined color space, or gamut, which defines the extent that a given set of RGB colors can be mixed. When converting from one medium to another, an image must go through some form of conversion which maps colors into the destination color space. The conversion process isn`t always straight forward, easy, or reversible. In video, two common analog composite color spaces are Y`tjv (used in PAL) and Y`IQ (used in NTSC). These two color spaces have been around since the beginning of color television, and are primarily used in video transmission. Another analog scheme used in broadcast studios is Y`, R`-Y`, B`-Y` (used in Betacam and Mll) which is a component format. Y`, R`-Y`,B`-Y` maintains the color information of RGB but in less space. From this, the digital component video specification, ITU-Rec. 601-4 (formerly CCIR Rec. 601) was based. The color space for Rec. 601 is symbolized as Y`CbCr. Digital video formats such as DV, Dl, Digital-S, etc., use Rec. 601 to define their color gamut. Digital composite video (for D2 tape) is digitized analog Y`UV and is seeing decreased use. Because so much information is contained in …