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LBR deactivation information exchange

Description: This report contains vugraphs of presentations given at the meeting. The topics covered include the following: FFTF Deactivation Strategy; Sodium Drain and Disposition; Sodium Processing; and Fuel Storage and Disposition.
Date: May 15, 1998
Creator: Guttenberg, S.
Partner: UNT Libraries Government Documents Department
open access

Chemicals and excess materials disposition during facility deactivation as a means of pollution prevention

Description: This paper presents several innovative and common sense approaches to pollution prevention that have been employed during facility deactivation at the Hanford Site in South Central Washington. It also presents several pollution prevention principles applicable to other projects. Innovative pollution prevention ideas employed at the Hanford site during facility deactivation included: (1) Recycling more than 185,000 gallons of radioactively contaminated nitric acid by sending it to an operating n… more
Date: May 28, 1998
Creator: Godfrey, S. D.
Partner: UNT Libraries Government Documents Department
open access

Predicting New Hampshire Indoor Radon Concentrations from geologic information and other covariates

Description: Generalized geologic province information and data on house construction were used to predict indoor radon concentrations in New Hampshire (NH). A mixed-effects regression model was used to predict the geometric mean (GM) short-term radon concentrations in 259 NH towns. Bayesian methods were used to avoid over-fitting and to minimize the effects of small sample variation within towns. Data from a random survey of short-term radon measurements, individual residence building characteristics, alon… more
Date: May 1, 1998
Creator: Apte, M. G.; Price, P. N.; Nero, A. V. & Revzan, K. L.
Partner: UNT Libraries Government Documents Department
open access

Potential Nationwide Improvements in Productivity and Health from Better Indoor Environments

Description: Theoretical considerations and empirical data suggest that existing technologies and procedures can improve indoor environments in a manner that significantly increases productivity and health. Existing literature contains moderate to strong evidence that characteristics of buildings and indoor environments significantly influence rates of respiratory disease, allergy and asthma symptoms, sick building symptoms, and worker performance. While there is considerable uncertainty in our estimates of… more
Date: May 1, 1998
Creator: Fisk, W.J. & Rosenfeld, A.H.
Partner: UNT Libraries Government Documents Department
open access

Phenomenology and cosmology of weakly coupled string theory

Description: The weakly coupled vacuum of E{sub 8} {circle_times} E{sub 8} heterotic string theory remains an attractive scenario for phenomenology and cosmology. The particle spectrum is reviewed and the issues of gauge coupling unification, dilaton stabilization and modular cosmology are discussed. A specific model for condensation and supersymmetry breaking, that respects known constraints from string theory and is phenomenologically viable, is described.
Date: May 18, 1998
Creator: Gaillard, Mary K.
Partner: UNT Libraries Government Documents Department
open access

Axionic hot dark matter in the hadronic axion window

Description: Mixed dark matter scenario can reconcile the COBE data and the observed large scale structure. So far the massive neutrino with a mass of a few eV has been the only discussed candidate for the hot dark matter component. We point out that the hadronic axion in the so-called hadronic axion window, f{sub a} {approx} 10{sup 6} GeV, is a perfect candidate as hot dark matter within the mixed dark matter scenario. The current limits on the hadronic axion are summarized. The most promising methods to v… more
Date: May 23, 1998
Creator: Moroi, Takeo & Murayama, Hitoshi
Partner: UNT Libraries Government Documents Department
open access

Irradiation creep of vanadium-base alloys.

Description: A study of irradiation creep in vanadium-base alloys is underway with experiments in the Advanced Test Reactor (ATR) and the High Flux Isotope Reactor (HFIR) in the US. Test specimens are thin-wall sealed tubes with internal pressure loading. The results from the initial ATR irradiation at low temperature (200-300 C) to a neutron damage level of 4.7 dpa show creep rates ranging from {approx}0 to 1.2 x 10{sup {minus}5}/dpa/MPa for a 500-kg heat of V-4Cr-4Ti alloy. These rates were generally lowe… more
Date: May 18, 1998
Creator: Tsai, H.; Matsui, H.; Billone, M. C.; Strain, R. V. & Smith, D. L.
Partner: UNT Libraries Government Documents Department
open access

Progress in metal ion separation and preconcentration : an overview.

Description: A brief historical perspective covering the most mature chemically-based metal ion separation methods is presented, as is a summary of the recommendations made in the 1987 National Research Council (NRC) report entitled ''Separation and Purification: Critical Needs and Opportunities''. A review of Progress in Metal Ion Separation and Preconcentration shows that advances are occurring in each area of need cited by the NRC. Following an explanation of the objectives and general organization of th… more
Date: May 19, 1998
Creator: Bond, A. H.
Partner: UNT Libraries Government Documents Department
open access

Microstructural examination of irradiated V-(4-5%)Cr-(4-5%)Ti.

Description: Microstructural examination results are reported for two heats of V-(4-5%) Cr-(4-5%)Ti irradiated in the EBR-II X530 experiment to 4.5 dpa at {approximately}400 C to provide an understanding of the microstructural evolution that may be associated with degradation of mechanical properties. Fine precipitates were observed in high density intermixed with small defect clusters for all conditions examined following the irradiation. The irradiation-induced precipitation does not appear to be affected… more
Date: May 4, 1998
Creator: Gelles, D. S.
Partner: UNT Libraries Government Documents Department
open access

Review of W and Z production at the Tevatron

Description: The CDF and D0 collaborations have used recent data taken at the Tevatron to perform QCD tests with W and Z bosons decaying leptonically. D0 measures the production cross section times branching ratio for W and Z bosons. This also gives an indirect measurement of the total width of the W boson: {Lambda}{sub W} = 2.126 {+-} 0.092 GeV. CDF reports on a direct measurement of {Lambda}{sub W} = 2.19 {+-} 0.19 GeV, in good agreement with the indirect determination and Standard Model predictions. D0's… more
Date: May 1, 1998
Creator: Gerber, Cecilia E.
Partner: UNT Libraries Government Documents Department
open access

Mechanical properties and microstructural characteristics of laser and electron-beam welds in V-4Cr-4Ti.

Description: Mechanical properties and microstructural characteristics of laser and electron-beam welds of a 500-kg heat of V4Cr4Ti were investigated in as-welded condition and after postwelding heat treatment by impact testing, microhardness measurement, optical microscopy, X-ray diffraction, and transmission electron microscopy (TEM). Ductile-brittle transition temperatures of the laser and electron-beam welds were significantly higher than that of the base metal. However, excellent impact properties coul… more
Date: May 18, 1998
Creator: Chung, H. M.
Partner: UNT Libraries Government Documents Department
open access

Results on Dijets with a Central Rapidity Gap from CDF

Description: Results on dijets with a central rapidity gap at {radical}s = 1800 GeV are briefly summarized. Preliminary new results from data at {radical}s = 630 GeV are presented and compared to those at {radical}s = 1800 GeV.
Date: May 1, 1998
Creator: Borras, K.
Partner: UNT Libraries Government Documents Department
open access

In-vessel fluid flow measurements using thermocouples cross-correlation.

Description: Fluid flow rate in high temperature and pressure vessels can be difficult to measure due to the associated harsh environment, inaccessible locations and pressure boundary integrity concerns. However, by using quick response miniature thermocouples to measure the naturally occurring temperature variations within the flow, the fluid velocity can be inferred from the transit time analysis. This flow measurement technique has other advantages such as the flow profile is not significantly disturbed,… more
Date: May 8, 1998
Creator: NguyenLe, Q.
Partner: UNT Libraries Government Documents Department
open access

Low-temperature MOCVD growth of oriented PbZr{sub x}Ti{sub 1-x}O{sub 3} thin films on Si substrates.

Description: Polycrystalline Pb(Zr{sub 0.6}Ti{sub 0.4})O{sub 3} (PZT) thin films, 3000-6000 {angstrom} thick, have been grown by metal-organic chemical vapor deposition (MOCVD) on (111)Pt/Ti/SiO{sub 2}/Si substrates at temperatures as low as 450-525 C. Random and (111)-oriented, or occasionally (100)-oriented, PZT films can be deposited directly on (111)Pt/Ti/SiO{sub 2}/Si. In addition, highly (100)-oriented films can be deposited consistently by using 150-250 {angstrom} thick (100)-oriented PbTiO{sub 3} (P… more
Date: May 8, 1998
Creator: Chen, N.
Partner: UNT Libraries Government Documents Department
open access

Lithium-endohedral C{sub 60} complexes.

Description: High capacity, reversible, lithium intercalated carbon anodes have been prepared, 855 m.Ah/g, which exceed the capacity for stage 1 lithium intercalated carbon anodes, 372 mAh/g. Since there is very little hydrogen content in the high capacity anode, the fullerene C{sub 60} lattice is used to investigate the nature of lithium ion bonding and spacing between lithiums in endohedral lithium complexes of C{sub 60}. Three lithium-endohedral complexes have been investigated using ab initio molecular … more
Date: May 4, 1998
Creator: Scanlon, L. G.
Partner: UNT Libraries Government Documents Department
open access

Characterizing transverse beam dynamics at the APS storage ring using a dual-sweep streak camera.

Description: We present a novel technique for characterizing transverse beam dynamics using a dual-sweep streak camera. The camera is used to record the front view of successive beam bunches and/or successive turns of the bunches. This extension of the dual-sweep technique makes it possible to display non-repeatable beam transverse motion in two fast and slow time scales of choice, and in a single shot. We present a study of a transverse multi-bunch instability in the APS storage ring. The positions, sizes,… more
Date: May 27, 1998
Creator: Yang, B.
Partner: UNT Libraries Government Documents Department
open access

Experimental observations to the electrical field for electrorefining of spent nuclear fuel in the Mark-IV electrorefiner.

Description: Experimental results from the pilot scale electrorefiner (Mark-IV ER) treating spent nuclear fuel are reported in this article. The electrorefining processes were carried out in a LiCl-KCl-UCl{sub 3} electrolyte. It has been noted that spool of molten cadmium below the electrolyte plays an important role in the electrorefining operations. In addition, formations of electrical shorting path between anode baskets and the electrorefiner vessel were observed, which lessened the uranium dissolution … more
Date: May 13, 1998
Creator: Li, S. X.
Partner: UNT Libraries Government Documents Department
open access

SUSY searches at the Tevatron

Description: CDF and D0 have performed searches for Supersymmetry with data collected at {radical}s = 1.8 TeV during the years 1992-95. These searches are based on detector signatures: events with appreciable missing transverse energy plus jets with or without dileptons can signal squark and gluino production; the spectacular signature of trilepton events can result from the production of charginos and neutralinos; and the inclusion of R parity violation can produce events with like-sign dileptons and no mi… more
Date: May 1, 1998
Creator: Chertok, Maxwell
Partner: UNT Libraries Government Documents Department
open access

EPR detection of light-generated nuclear coherences in photosynthetic reaction centers.

Description: In this study we first discuss a pulsed EPR experiment designed to establish the mechanism of coherence generation [1]. The pulse sequence employed, flash-t-({pi}/2){sub x}-{tau}, consists of a short laser pulse at time zero, followed by a variable period t. At the end of this period a non-ideal ({pi}/2) microwave pulse is applied. The resulting free-induction decay at fixed detection time {tau} is then monitored as a function of successively incremented values of t. For P{sub 700}{sup +} A{sub… more
Date: May 4, 1998
Creator: Bechtold, M.
Partner: UNT Libraries Government Documents Department
open access

Characterization of spent EBR-II driver fuel.

Description: Operations and material control and accountancy requirements for the Fuel Conditioning Facility demand accurate prediction of the mass flow of spent EBR-II driver fuel into the facility. This requires validated calculational tools that can predict the burnup and isotopic distribution in irradiated Zr-alloy fueled driver assemblies. Detailed core-follow depletion calculations have been performed for an extensive series of EBR-II runs to produce a database of material inventories for the spent fu… more
Date: May 4, 1998
Creator: McKnight, R. D.
Partner: UNT Libraries Government Documents Department
open access

Cryocooler applications for high-temperature superconductor magnetic bearings.

Description: The efficiency and stability of rotational magnetic suspension systems are enhanced by the use of high-temperature superconductor (HTS) magnetic bearings. Fundamental aspects of the HTS magnetic bearings and rotational magnetic suspension are presented. HTS cooling can be by liquid cryogen bath immersion or by direct conduction, and thus there are various applications and integration issues for cryocoolers. Among the numerous cryocooler aspects to be considered are installation; operating tempe… more
Date: May 22, 1998
Creator: Niemann, R. C.
Partner: UNT Libraries Government Documents Department
open access

BWR drywell behavior under steam blowdown.

Description: Historically, thermal hydraulics analyses on Large Break Loss of Coolant Accidents (LOCA) have been focused on the transients within the reactor or steam generator. Few have studied the effects of steam blowdown on the containment building. This paper discusses some theoretical issues as well as presenting numerical and experimental results of the blowdown tests performed at the Purdue University Multi-Dimensional Integrated Test Assembly (PUMA).
Date: May 8, 1998
Creator: NguyenLe, Q.
Partner: UNT Libraries Government Documents Department
open access

Calibration of an Advanced Photon Source linac beam position monitor used for positron position measurement of a beam containing both positrons and electrons.

Description: The Advanced Photon Source (APS) linac beam position monitors can be used to monitor the position of a positron beam also containing electrons. To accomplish this task, both the signal at the bunching frequency of 2856 MHz and the signal at 2 x 2856 MHz are acquired and processed for each stripline. The positron beam position is obtained by forming a linear combination of both 2856- and 5712-MHz signals for each stripline and then performing the standard difference over sum computation. The req… more
Date: May 19, 1998
Creator: Sereno, N. S.
Partner: UNT Libraries Government Documents Department
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