The strange-quark vector current {rho}-to-{pi} meson transition form factor is computed at one-loop order using strange meson intermediate states. A comparison is made with a {phi}-meson dominance model estimate. They find that one-loop contributions are comparable in magnitude to those predicted by {phi}-meson dominance. It is possible that the one-loop contribution can make the matrix element as large as those of the electromagnetic current mediating vector meson radiative decays. However, due to the quadratic dependence of the one-loop results on the hadronic form factor cut-off mass, a large uncertainty in the estimate of the loops is unavoidable. These results indicate that non-nucleonic strange quarks could contribute appreciably in moderate-{vert_bar}Q{sup 2}{vert_bar} parity-violating electron-nucleus scattering measurements aimed at probing the strange-quark content of the nucleon.

A finite element formulation which derives constitutive response from crystal plasticity theory is used to examine localized deformation in fcc polycrystals. The polycrystals are simple, idealized arrangements of grains. Localized deformations within individual grains lead to the development of domains that are separated by boundaries of high misorientation. Shear banding is seen to occur on a microscopic scale of grain dimensions. The important consequences of these simulations are that the predicted local inhomogeneities are meeting various requirements which make them possible nucleation sites for recrystallization.

The NASA Standard Detonator (NSD) is employed in support of a number of current applications, including the Space Shuttle. This effort was directed towards providing test results to characterize the output of this device for its use in a safe and arm device. As part of the investigation, flash X-ray was used to provide stop-motion photographs of the flying metal plate that is created by initiation of the detonator. This provided researchers with a better understanding of the shape and character of the high-velocity disk as it propagated across the gap between the detonator and next assembly. The second portion of the study used a velocity interferometer to evaluate the acceleration and velocity histories of the flying plate, providing a quantified assessment of the detonator`s ability to initiate the explosive in the next explosive.

The DO collaboration reports on a search for the Standard Model top quark in p{bar p} collisions at {radical}s = 1.8 TeV at the Fermilab Tevatron, with an integrated luminosity of approximately 50 pb{sup {minus}1}. We have searched for t{bar t} production in the dilepton and single-lepton decay channels, with and without tagging of b quark jets. We observe 17 events with an expected background of 3.8 {plus_minus} 0.6 events. The probability for an upward fluctuation of the background to produce the observed signal is 2 {times} 10{sup {minus}6} (equivalent to 4.6 standard deviations). The kinematic properties of the excess events are consistent with top quark decay. We conclude that we have observed the top quark and measure its mass to be 199{sub {minus}21}{sup +19} (stat.) {plus_minus}22 (syst.) GeV/c{sup 2} and its production cross section to be 6.4 {plus_minus} 2.2 pb.

Beginning with a tracking code for the LHC, we construct the canonical generator of the full-turn map in polar coordinates. For very fast mapping we adopt a model in which the momentum is modulated sinusoidally with a period of 130 turns (very close to the synchrotron period). We achieve symplectic mapping of 10{sup 7} turns in 3.6 hours on a workstation. Quasi-invariant tori are constructed on the Poincare section corresponding to multiples of the synchrotron period. The possible use of quasi-invariants in derivin, long-term bounds on the motion is discussed.

Powerful CW proton linear accelerators (100 mA at 0.5--1 GeV) are being proposed for spallation neutron source applications.These production accelerators require high availability and reliability. A microwave proton source, which has already demonstrated several key beam requirements, was operated for one week (170 hours) in a dc mode to test the reliability and lifetime of its plasma generator. The source was operated with 570 W of microwave (2.45 GHz) discharge power and with a 47-kV extraction voltage. This choice of operating parameters gave a proton current density of 250-mA/cm{sup 2} at 83% proton fraction, which is sufficient for a conservative dc injector design. The beam current was 60--65 mA over most of the week, and was sufficiently focused for RFQ injection. Total beam availability, defined as 47-keV beam-on time divided by elapsed time, was 96.2%. Spark downs in the high voltage column and a gas flow control problem caused all the downtime; no plasma generator failures were observed.

This paper discusses the emergence of a new, necessary philosophy for the successful implementation of advanced technologies to improve plant performance and longevity. Thus philosophy is necessary to ensure the expected return on the initial capital investment is realized. This paper defines the elements of an Operations and Maintenance (O&M) methodology that utilizes a holistic approach which considers all aspects of the supporting infrastructure (Operations, Maintenance, Engineering, Training, and Administration) as integral parts of the whole system. This paper also discusses a network structure that provides an intelligent integrated plant communication network for the measurement and management of plant performance goals.

The development of a three-dimensional spatially evolving compressible mixing layer is investigated numerically using a parallel implementation of Adaptive Mesh Refinement (AMR) on a Cray C-90. The parallel implementation allowed the flow to be highly resolved while significantly reducing the wall-clock runtime. A sustained computation rate of 5.3 Gigaflops including I/O was obtained for a typical production run on a 16 processor machine. A novel mixing layer configuration is investigated where a pressure mismatch is maintained between the two inlet streams. In addition, the sonic character of the two streams is sufficiently different so that the pressure relief wave is trapped in the high speed stream. The trapped wave forces the mixing layer to form a characteristic cellular pattern. The cellular structure introduces curvature into the mixing layer that excites centrifugal instabilities characterized by large-scale counter-rotating vortical pairs embedded within the mixing layer. These are the dominant feature of the flow. Visualizations of these structures in cross-section show the pumping action which lifts dense fluid up into light gas. This effect has a strong impact on mixing enhancement as monitored by a conserved scalar formulation. Once the large-scale structures axe well established in the flow and undergo intensification from favorable …

Under U.S. Department of Energy, Pittsburgh Energy Technology Center (PETC) support, the development of a High Efficiency Advanced Coal Combustor (HEACC) has been in progress since 1987 at the ABB Power Plant Laboratories. As summarized in previous publications on the subject, the initial work produced an advanced coal firing system that was capable of firing both water-based and dry pulverized coal in an industrial boiler environment. With continued DOE-PETC support, carried out in cooperation with the Energy and Fuels Research Center of The Pennsylvania State University (Penn State), the HEACC burner concept has been used as a major component in a system design intended for industrial-scale, coal fired retrofit applications. The overall objective of the current work is to demonstrate the technical and economic feasibility of retro a gas/oil-designed industrial boiler to burn micronized coal. In this respect, the major technical goals for the combustion system design have included: a compact, easy to retrofit burner design; low NOx generation, while maintaining high combustion efficiency; commercially acceptable combustion air pressure drop and burner turndown ratio; and integration of coal preparation system controls into boiler control system The design of the HEACC burner is based on the well established principle of internal …

A metal-organic chemical vapor deposition (MOCVD) process for the growth of crystalline-as-deposited cerium doped calcium thiogallate (CaGa{sub 2}S{sub 4}:Ce) at substrate temperatures less than 600{degree}C has been developed. Blue-green electroluminescence was observed with a luminance of {approx} 2 cd/m{sup 2} at 40 volts above threshold using 60 Hz drive frequency. Threshold voltages were approximately 200 V.

This paper will discuss the value of assessments in Lawrence Livermore National Laboratory`s Waste Certification Programs by: introducing the organization and purpose of the LLNL Waste Certification Programs for transuranic, low-level, and hazardous waste; examining the differences in internal assessment/audit requirements for these programs; discussing the values and costs of assessments in a waste certification program; presenting practical recommendations to maximize the value of your assessment programs; and presenting improvements in LLNL`s waste certification processes that resulted from assessments.

The thermal performance of a commercially available 80 gallon, solar storage tank with an integral wrap-around heat exchanger is characterized experimentally an indoor test stand. The experimental results are used to evaluated the accuracy of a previously developed simulation model. Heat input on the collector side of the heat exchanger is held constant causing the heat transfer to reach a quasi-steady state. Temperatures in the heat exchanger and tank increase with time, however, the temperature differences across the heat exchanger remain nearly constant. Several combinations of heat input and collector loop flow are investigated. The development of the tank temperature profiles over time and the overall heat transfer performance predicted by the model are compared with experimental results. The influence of an electric auxiliary heater located in the top of the solar storage tank on the heat exchanger performance is investigated. Experimental normalization of the model is considered and modifications to the model and experiments are recommended.

A comparative study of ArF- and KrF-laser generated carbon plasmas has been performed under pulsed laser deposition conditions of amorphous diamond-like carbon (DLC) films. Gated-ICCD species-resolved imaging, luminescence spectroscopy and ion probe diagnostics have revealed distinct differences between the carbon plumes generated by ArF- and KrF-lasers. KrF-laser (6.7 J/cm{sup 2}) irradiation produces a less energetic carbon plasma containing larger amounts of luminescent C{sub 2} compared with ArF-laser ablation at the same energy fluence. Spectroscopic ellipsometry and EELS analysis of the DLC films deposited on Si <100> and NaCl substrates were utilized to characterize the high quality ArF- and KrF-laser deposited films (up to 84% of sp{sup 3} bonded carbon for 7 J/cm{sup 2}-ArF-laser DLC film). The more energetic and highly-atomized ArF-laser carbon plasma appears to be responsible for the better diamond-like properties.

The packaging, designated the H1636A is a high-performing packageing for large payloads. The H1636A is 50 in. in diameter and 113 in. in length and weighs approximately 4600 lb when empty. The design objective was to meet 1996 proposed IAEA Type C criteria for air transport of large quantities of radioactive material (RAM). That is, the package should survive the standard Type B tests and more severe tests such as an impact onto an unyielding target at 280 ft/s and a one-hour jet fuel fire. The packaging consists of a large double-walled stainless steel outer drum filled with uniform density polyurethane foam. A stainless steel containment vessel (CV) with an inside diameter of 23 in. and a length of 78 in. carries the RAM. The CV has a nominal thickness of 0.375 in. and seals with two elastomeric 0-rings. The lid of the CV is joined to the body with a unique closure called a tape joint. The tape joint utilizes interlocking features preloaded with wedges and can withstand significant deformation.

Radioisotope yields from 1.85-GeV proton interactions in a natural isotopic composition Mo target and those from 1.85- and 5.0-GeV protons in natural Te targets were measured at Lawrence Berkeley Laboratory`s Bevatron. The radioisotope yields were determined by {gamma}-counting the targets using a 100-cm{sup 3} coaxial Ge detector following the irradiations. Cross sections were determined for the production of 31 radioactive nuclides, ranging from Z = 35, A = 74, to Z = 43, A = 97, from the Mo target and for 47 radioactive nuclides, ranging from Z = 35, A = 75, to Z = 53, A = 130 from the Te targets.