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RESULTS FROM BETATRON PHASE MEASUREMENTS IN RHIC DURING THE SEXTANT TEST.

Description: The Sextant Test of the Relativistic Heavy Ion Collider (RHIC) was an important step towards its completion. One sixth of the two RHIC accelerators was fully commissioned. Gold ion beam was injected and transported through one sextant of one of the two rings. The betatron phase advance per cell was measured by recording differences in the horizontal and vertical positions of the beam at the end of the sextant due to a sequence of correction dipole kicks along the beam line. Measurement results show excellent agreement with predicted values, confirming that production measurements of the integral functions of the quadrupoles were very accurate, and that the polarity of all elements (correction dipoles, quadrupoles, dipoles etc.) was correct.
Date: June 26, 1998
Creator: TRBOJEVIC, D.
Partner: UNT Libraries Government Documents Department

An Annotated Bibliography of HVDC Transmission and FACTS Devices, 1996-1997.

Description: This edition of the Annotated Bibliography of HVDC Transmission and FACTS Devices continues work begun in 1962 by the late Erik Bromberg, Bonneville Power Administration Librarian. His original bibliography covered the period 1932--1962. Subsequent editions were compiled by Bromberg, Val S. Lava, and Wayne Litzenberger, all of Bonneville Power Administration. Beginning with the 1991--1993 edition, the scope of the bibliography was expanded to include flexible ac transmission (FACTS) devices. This 1996--1997 edition also contains information for 1998. Preparation of the present edition took place primarily in May-June of 1998. All pertinent references have been included that were available to the editors at the time of preparation. Papers for the 1998 IEEE Winter and Summer Power Meetings and 1998 T and D Conference have been included. This edition contains the organizational affiliation of the first-named author as an aid to accessing the reference. Unfortunately, space limitations prevented the inclusion of the affiliations of all authors. Some minor editorial changes have been made to abstracts to ensure consistency in style and syntax.
Date: June 1, 1998
Creator: Litzenberger, Wayne H.; Varma, Rajiv K. & Flanagan, John D.
Partner: UNT Libraries Government Documents Department

Cluster ion beam polishing for inertial confinement fusion target capsules

Description: Targets for Inertial Confinement Fusion (ICF) typically consist of a hollow, spherical capsule filled with a mixture of hydrogen isotopes. Typically, these capsules are irradiated by short, intense pulses of either laser light (``direct drive``) or laser-generated. x-rays (``indirect drive``), causing them to implode This compresses and heats the fuel, leading to thermonuclear fusion. This process is highly sensitive to hydrodynamic (e.g., Rayleigh-Taylor) instabilities, which can be initiated by imperfections in the target. Thus, target capsules must be spherical and smooth One of the lead capsule designs for the National Ignition Facility, a 1.8 MJ laser being built at Livermore, calls for a 2-mm- diam capsule with a 150-{micro}m-thick copper-doped beryllium wall. These capsules can be fabricated by sputter depositing the metal onto a spherical plastic mandrel. This results in surfaces with measured Rq`s of 50 to 150 nm, as measured with an atomic force microscope For optimal performance the roughness should be below 10 nm rms We have begun studying the use of ion cluster beam polishing as a means of improving the surface finish of as-deposited capsules In this approach, a batch of capsules would be agitated in a bounce pan inside a vacuum chamber during exposure to the cluster beam. This would ensure a uniform beam dose around the capsule. We have performed preliminary experiments on both Be flats and on a stationary Be capsule On the capsule, the measured Rq went from 64 nm before polishing to 15 nm after This result was obtained without any effort at process optimization. Similar smoothing was observed on the planar samples
Date: June 9, 1998
Creator: McEachern, R.
Partner: UNT Libraries Government Documents Department

Operator scheduling at the Advanced Light Source

Description: Scheduling Operations staff at the Advanced Light Source (ALS) has evolved from 5 shifts/week for commissioning operations in 1992 to the present 24 hour/day, 21 shift coverage as the ALS went to full operation for users. A number of schedules were developed and implemented in an effort to accommodate changing ALS shift coverage requirements. The present work schedule and the lessons learned, address a number of issues that are useful to any facility that is operating 24 hours/day, 7 days/week.
Date: June 1998
Creator: Miller, B.
Partner: UNT Libraries Government Documents Department

Supplement analysis 2 of environmental impacts resulting from modifications in the West Valley Demonstration Project

Description: The West Valley Demonstration Project, located in western New York, has approximately 600,000 gallons of liquid high-level radioactive waste (HLW) in storage in underground tanks. While corrosion analysis has revealed that only limited tank degradation has taken place, the failure of these tanks could release HLW to the environment. Congress requires DOE to demonstrate the technology for removal and solidification of HLW. DOE issued the Final Environmental Impact Statement (FEIS) in 1982. The purpose of this second supplement analysis is to re-assess the 1982 Final Environmental Impact Statement's continued adequacy. This report provides the necessary and appropriate data for DOE to determine whether the environmental impacts presented by the ongoing refinements in the design, process, and operations of the Project are considered sufficiently bounded within the envelope of impacts presented in the FEIS and supporting documentation.
Date: June 23, 1998
Partner: UNT Libraries Government Documents Department

Geothermal high temperature instrumentation applications

Description: A quick look at the geothermal industry shows a small industry producing about $1 billion in electric sales annually. The industry is becoming older and in need of new innovative solutions to instrumentation problems. A quick look at problem areas is given along with basic instrumentation requirements. The focus of instrumentation is on high temperature electronics.
Date: June 11, 1998
Creator: Normann, R.A. & Livesay, B.J.
Partner: UNT Libraries Government Documents Department

The Heisenberg representation of quantum computers

Description: Since Shor`s discovery of an algorithm to factor numbers on a quantum computer in polynomial time, quantum computation has become a subject of immense interest. Unfortunately, one of the key features of quantum computers--the difficulty of describing them on classical computers--also makes it difficult to describe and understand precisely what can be done with them. A formalism describing the evolution of operators rather than states has proven extremely fruitful in understanding an important class of quantum operations. States used in error correction and certain communication protocols can be described by their stabilizer, a group of tensor products of Pauli matrices. Even this simple group structure is sufficient to allow a rich range of quantum effects, although it falls short of the full power of quantum computation.
Date: June 24, 1998
Creator: Gottesman, D.
Partner: UNT Libraries Government Documents Department

Post-accident inhalation exposure and experience with plutonium

Description: This paper addresses the issue of inhalation exposure immediately afterward and for a long time following a nuclear accident. For the cases where either a nuclear weapon burns or explodes prior to nuclear fission, or at locations close to a nuclear reactor accident containing fission products, a major concern is the inhalation of aerosolized plutonium (Pu) particles producing alpha-radiation. We have conducted field studies of Pu- contaminated real and simulated accident sites at Bikini, Johnston Atoll, Tonopah (Nevada), Palomares (Spain), Chernobyl, and Maralinga (Australia).
Date: June 1, 1998
Creator: Shinn, J
Partner: UNT Libraries Government Documents Department

Flammable gas concentrations in ex-tank volumes

Description: A simple two-volume model was defined and used for calculating flammable gas concentrations within headspace volumes of single-shell tanks, and within smaller ex-tank volumes connected to the headspace. Assumptions and parameters used to characterize the headspace portion of the model were taken from the GRE Analysis Tool (AT) for simulating gas release events. Additional assumptions used to construct the ex-tank portion of the two-volume model were conservative extensions of those made within the AT, and chosen to simulate headspace to ex-tank gas-flow conditions that would maximize ex-tank concentrations. Numerical evaluations of the two-volume model were performed over a range of headspace GRE conditions and representative ex-tank parameters. To assure consistency with the AT, the range of headspace parameters was taken from 1000 simulated GREs generated by the AT computer code RESOLVE. Based upon waste level fill factors, three tanks (TX-102, SX-103, and TX 112) were chosen to represent typical large, medium, and small headspace volumes available in actual SSTs. Engineering drawings of these tanks were used to determine values of their ex-tank parameters (V2`s and estimates for the gas-flow fraction ``a`` into the specific V2). The results of these evaluations were used to compare time periods for which flammable gas concentrations in the tank headspace and the ex-tank volumes exceeded the lower flammability limit for upward flame propagation. These results indicate that even for relatively small flow fractions, headspace concentrations that exceed the LFI, can cause delayed ex-tank concentrations to also exceed the LFLU. The extent to which this occurs is determined mostly by the geometrical aspects of the model, as expressed in the effective volume fraction parameter.
Date: June 17, 1998
Creator: Wittekind, W.D.
Partner: UNT Libraries Government Documents Department

Rationale for the closure of the soil density unreviewed safety question and recommended structural analyses improvements for the TWRS underground storage facilities

Description: The purpose of this report is twofold. First, this report documents the technical evaluation supporting the Project Hanford Management Contract (PHMC) contractor recommendation to close the Unreviewed Safety Question (USQ) as originally evaluated in TF-94-0260, Soil Compaction Test Data Indicates Soil Density in Excess of Density Used in Tank Qualification Analysis for AP Tank Farm. Second, this report describes the status of existing structural analyses for the Tank Waste Remediation System (TWRS) waste storage structures and outlines the associated technical upgrades being considered by the contractor. This second feature of the report serves to communicate the distinction between the soil density issue which is the topic of the open USQ and other technical issues which are important to the contractor from a programmatic standpoint. Contractor actions to address the latter technical issues would support improvements in day-to-day operations (e.g., provide possible relaxations in soil load restrictions) but are not necessary to close the soil density USQ. Section 2.0 of this report documents the rationale for the PHMC contractor recommendation to the Department of Energy (DOE) to close the soil density USQ. Section 3.0 documents the recommended structural analyses improvements for the double-shell tanks (DSTs) which are the structures associated with the soil density USQ. Sections 4.0 and 5.0 provide, for completeness, the same information for single-shell tanks (SSTs), double-contained receiver tanks (DCRTs), catch tanks and inactive miscellaneous underground storage tanks (IMUSTs). Section 6.0 provides the conclusions of this report.
Date: June 12, 1998
Creator: Morris, K.H.
Partner: UNT Libraries Government Documents Department

Search for high mass photon pairs in p{anti p} collisions at {radical}s = 1.8 TeV

Description: The authors present results of a search for diphoton resonances produced inclusively and in association with a vector boson using 100 pb{sup {minus}1} of p{anti p} collisions using the CDF detector. They set upper limits on the product of cross section times branching ratio for p{anti p} {r_arrow} {gamma}{gamma} {r_arrow} X and p{anti p} {r_arrow} {gamma}{gamma} {r_arrow} W/Z. Using a NLO prediction for associated production cross section of a Higgs with a vector boson (W or Z), they set an upper limit on the branching ratio for H {r_arrow} {gamma}{gamma}. They set a lower limit on the mass of a `bosophilic` Higgs boson (e.g. one which couples only to {gamma}, W, and Z bosons with Standard Model couplings) of 82 GeV/c{sup 2} at 95% C.L.
Date: June 29, 1998
Creator: Wilson, P. J.
Partner: UNT Libraries Government Documents Department

Applications of direct chemical oxidation to demilitarization

Description: Research is reported concerning an aqueous process for oxidative destruction of solid- and liquid organic wastes, including ongoing work relevant to demilitarization This process uses acidified ammonium- or sodium peroxydisulfate and operates at ambient pressure and at temperatures of 80- 100 C The oxidant may be regenerated by electrolysis of the sulfate by- product at Pt anodes at roughly 80% coulombic efficiency, even in the presence of inorganic contaminants (e g , nitrate, phosphate or chloride) found in the original waste and entrained in the recycle stream Integral rate constants have been determined for the oxidation of diverse organic compounds at low concentrations (50 ppm, C), with rate constants (based on equivalents) of 0 004-O 02 miri Higher concentrations generally react at a 2-4X higher rate. The process has been carried through full- scale laboratory tests and initial pilot plant tests on chlorinated solvents, using a hydrolysis pretreatment Integral rate data indicate throughput rates of about 200 kg- C/m3-day The process may benefit the demilitarization efforts in various specialized applications destruction of solvents; destruction of trace propellants and explosives in shell casings remaining after bulk removal, destruction of red and pink waters, in situ remediation of soils at open pit burning/detonation sites; and as a regenerative filter for offgas carrying toxic or explosive substances.
Date: June 1, 1998
Creator: Cooper, J.F., LLNL
Partner: UNT Libraries Government Documents Department

{sup 16}O neutron cross section evaluation

Description: This work has resulted from a need to compute more accurately the neutron scattering cross sections and angular distributions for {sup 16}O. Several oxygen evaluations have been performed in the past with R-Matrix theory, including ENDF/B-V and ENDF/B-VI. ENDF/B-VI is an improvement over ENDF/B-V, but still underpredicts in general the forward scattering of neutrons below 2.5 MeV. R-Matrix theory is used in describing cross sections at and near the resonance energies; but may not always be adequate in describing cross sections between resonances, especially when they are widely spaced. The optical (potential well) model of the nucleus is very good in representing cross sections that vary smoothly with energy, but not at describing all of the detailed resonance cross sections. A combination of the potential well model and R-Matrix theory was used for this work to represent cross sections with isolated resonances with large spacings between them. The total neutron cross section of oxygen-16 below 3.0 MeV has widely separated resonances and a dip in the cross section at 2.35 MeV. In the vicinity of resonances, where cross sections vary rapidly with energy, R-Matrix theory has been successful in fitting experimental data. In the region between resonances, an analytical procedure with physical basis is needed that agrees with data over a wide range of energies bracketing regions where experimental measurements are lacking.
Date: June 1, 1998
Creator: Caro, E.
Partner: UNT Libraries Government Documents Department

The role of Cr antiferromagnetism on interlayer magnetic coupling in Fe/Cr multilayered systems

Description: Many experiments have verified the presence of a spin-density wave (SDW) within the Cr spacer of Fe/Cr multilayers and wedges. The authors review the recently-proposed interlayer magnetic coupling mediated by a SDW. Unlike previously proposed mechanisms, this magnetic coupling is strongly temperature-dependent. Depending on the temperature and the number N of Cr monolayers (ML), the SDW may be either commensurate (C) or incommensurate (I) with the bcc Cr lattice.
Date: June 1, 1998
Creator: Shi, Z.P. & Fishman, R.S.
Partner: UNT Libraries Government Documents Department

Technical report for the generic site add-on facility for plutonium polishing

Description: The purpose of this report is to provide environmental data and reference process information associated with incorporating plutonium polishing steps (dissolution, impurity removal, and conversion to oxide powder) into the genetic-site Mixed-Oxide Fuel Fabrication Facility (MOXFF). The incorporation of the plutonium polishing steps will enable the removal of undesirable impurities, such as gallium and americium, known to be associated with the plutonium. Moreover, unanticipated impurities can be removed, including those that may be contained in (1) poorly characterized feed materials, (2) corrosion products added from processing equipment, and (3) miscellaneous materials contained in scrap recycle streams. These impurities will be removed to the extent necessary to meet plutonium product purity specifications for MOX fuels. Incorporation of the plutonium polishing steps will mean that the Pit Disassembly and Conversion Facility (PDCF) will need to produce a plutonium product that can b e dissolved at the MOXFF in nitric acid at a suitable rate (sufficient to meet overall production requirements) with the minimal usage of hydrofluoric acid, and its complexing agent, aluminum nitrate. This function will require that if the PDCF product is plutonium oxide powder, that powder must be produced, stored, and shipped without exceeding a temperature of 600 C.
Date: June 1998
Partner: UNT Libraries Government Documents Department

Recent progress in GaInAsSb thermophotovoltaics grown by organometallic vapor phase epitaxy

Description: Studies on the materials development of Ga{sub 1{minus}x}In{sub x}As{sub y}Sb{sub 1{minus}y} alloys for thermophotovoltaic (TPV) devices are reviewed. Ga{sub 1{minus}x}In{sub x}As{sub y}Sb{sub 1{minus}y} epilayers were grown lattice matched to GaSb substrates by organometallic vapor phase epitaxy (OMVPE) using all organometallic precursors including triethylgallium, trimethylindium, tertiarybutylarsine, and trimethylantimony with diethyltellurium and dimethylzinc as the n- and p-type dopants, respectively. The overall material quality of these alloys depends on growth temperature, In content, V/III ratio, substrate misorientation, and to a lesser extent, growth rate. A mirror-like surface morphology and room temperature photoluminescence (PL) are obtained for GaInAsSb layers with peak emission in the wavelength range between 2 and 2.5 {micro}m. The crystal quality improves for growth temperature decreasing from 575 to 525 C, and with decreasing In content, as based on epilayer surface morphology and low temperature PL spectra. A trend of smaller full width at half-maximum for low temperature PL spectra is observed as the growth rate is increased from 1.5 to 2.5 and 5 {micro}m/h. In general, GaInAsSb layers grown on (100) GaSb substrates with a 6{degree} toward (111)B misorientation exhibited overall better material quality than layers grown on the more standard substrate (100)2{degree} toward (110). Consistent growth of high performance lattice-matched GaInAsSb TPV devices is also demonstrated.
Date: June 1, 1998
Creator: Wang, C.A.; Choi, H.K.; Oakley, D.C. & Charache, G.W.
Partner: UNT Libraries Government Documents Department

Implementation of passive samplers for monitoring volatile organic compounds in ground water at the Kansas City Plant

Description: Passive sampling for monitoring volatile organic compounds (VOCs) has been suggested as a possible replacement to the traditional bailer method used at the Department of Energy Kansas City Plant (KCP) for routine groundwater monitoring. To compare methods, groundwater samples were collected from 19 KCP wells with VOC concentrations ranging from non-detectable to > 100,000 {micro}g/L. Analysis of the data was conducted using means and medians of multiple measurements of TCE, 1,2-DCE, 1,1-DCE and VC. All 95% confidence intervals of these VOCs overlap, providing evidence that the two methods are similar. The study also suggests that elimination of purging and decontamination of sampling equipment reduces the labor required to sample by approximately 32%. Also, because the passive method generates no waste water, there are no associated disposal costs. The results suggest evidence to continue studies and efforts to replace traditional bailer methods with passive sampling at KCP based on cost and the similarity of the methods.
Date: June 1, 1998
Creator: Gardner, F.G.; Korte, N.E.; Wilson-Nichols, M.J.; Baker, J.L. & Ramm, S.G.
Partner: UNT Libraries Government Documents Department

Hard x-ray production from high intensity laser solid interactions

Description: Intense laser (> 10{sup 21} W/cm{sup 2}) driven hard x-ray sources offer a new alternative to conventional electron accelerator bremsstrahlung sources. These laser driven sources offer considerable simplicity in design and cost advantage for multiple axis views and have the potential for much higher spatial and temporal resolution than is achievable with accelerator sources We have begun a series of experiments using the Petawatt Laser system at LLNL to determine the potential of these sources for radiography applications Absolutely calibrated spectra extending to 20 MeV and high resolution radiographs through a {rho}r{>=}150 gm/cm{sup 2} have been obtained The physics of these sources and the scaling relationships and laser technology required to provide the dose levels necessary for radiography applications will be discussed Diagnostics of the laser produced electrons and photons will be addressed
Date: June 3, 1998
Creator: Sefcik, J. A.
Partner: UNT Libraries Government Documents Department

High temperature properties of alloys being considered for design of a concentric canister launcher

Description: This report describes a study to determine the high temperature mechanical properties of several titanium alloys and to compare them with properties of AISI 316L stainless steel and ASTM A 387 structural steel. The steel materials are less costly to procure but exhibit good resistance to corrosion in seawater environments. Six titanium alloys were evaluated as candidate materials for use in a c Concentric Canister Launcher (CCL). Each titanium alloy was tested at three temperatures (68°, 2000°F, and 2400°F). Strain-rate changes tests were used to determine the strain rate sensitivity of the alloys at each test temperature. Optical metallography was performed on two of the alloys to determine the relationship between test temperature and microstructure (presence of second phase precipitates, grain size). Complete test results are includes, a long with figures and tables of test data.
Date: June 1, 1998
Creator: Kassner, M E; Lowry, R W & Rosen, R S
Partner: UNT Libraries Government Documents Department

The supercritical pomeron in QCD.

Description: Deep-inelastic diffractive scaling violations have provided fundamental insight into the QCD pomeron, suggesting a single gluon inner structure rather than that of a perturbative two-gluon bound state. This talk outlines a derivation of a high-energy, transverse momentum cut-off, confining solution of QCD. The pomeron, in first approximation, is a single reggeized gluon plus a ''wee parton'' component that compensates for the color and particle properties of the gluon. This solution corresponds to a super-critical phase of Reggeon Field Theory.
Date: June 29, 1998
Creator: White, A. R.
Partner: UNT Libraries Government Documents Department

Corrosion performance of structural alloys in oxygen/sulfur/chlorine-containing environments.

Description: Component reliability and long-term trouble-free performance of structural materials are essential in power-generating processes that utilize coal as a feedstock. The combustion environments encompass a wide range of oxygen partial pressures, from excess-air conditions in conventional systems to air-deficient conditions in low-NO{sub x} systems. Apart from the environmental aspects of the effluent from coal combustion, one concern from the systems standpoint is the aggressiveness of the combustion environment toward boiler structural components such as waterwall tubes and steam superheaters. The corrosion tests in this program address the individual and combined effects of oxygen, sulfur, and chlorine on the corrosion response of several ASME-coded and noncoded boiler materials exposed to air-deficient and excess-air combustion conditions. Data in this paper address the corrosion behavior of structural materials such as Type 347 stainless steel, Alloys 800, 825, 625, 214, and Hastelloy X when exposed at 650 C to excess-air combustion conditions with and without HCl. Thermodynamic calculations were made to evaluate the gas chemistries formed from coal combustion. The results of such calculations, coupled with oxygen/sulfur/chlorine thermochemical diagrams, were used to select the gas environments for the laboratory test program. Results are presented for weight change, thickness loss, microstructural characteristics of corrosion products, mechanical integrity and cracking of scales, and the mechanistic understanding gained on the role of sulfur and chlorine in the corrosion process.
Date: June 22, 1998
Creator: Natesan, K.
Partner: UNT Libraries Government Documents Department

Columbia River : Select Area Fishery Evaluation project : 1995-96 Annual Reports.

Description: Water quality monitoring was conducted from November 1994 through October 1996 at five Oregon and three Washington select area study sites in the lower Columbia River. Physicochemical monitoring and aquatic biomonitoring programs were established to profile baseline parameters at each study site and document differences between study sites. Data collected at study sites where fish rearing operations were initiated indicate a potential negative impact on the surrounding benthic invertebrate communities.
Date: June 1, 1998
Creator: Hirose, Paul; Miller, Marc & Hill, Jim
Partner: UNT Libraries Government Documents Department

Optics damage inspection for the NIF

Description: Two optics damage inspection systems will be implemented on the National Ignition Facility (NIF), one to inspect optics within the laser and transport sections and the other to inspect the final optics at the target chamber. Both systems use dark-field imaging technology to enhance resolution of defects. Details of each system design will be provided. A functional optics damage inspection system prototype, using dark-field imaging technology, is currently in operation on the Beamlet laser. This system provides us with the opportunity to measure non-ideal optical surfaces expected to be present on NIF. Prototype details and performance will be presented.
Date: June 1, 1998
Creator: Thompson, C. E., LLNL
Partner: UNT Libraries Government Documents Department