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Structural Formation Studies of UV-Catalyzed Gels and Aerogels by Light Scattering

Description: The skeletal structure of aerogel is determined before, during, and after the gel is formed. Supercritical drying of aerogel largely preserves the pore structure that is determined near the time of gelation. To better understand these gel formation mechanisms we carried out measurements of the time evolution of light scattering in a series of gels prepared without conventional acid or base catalysis. Instead, ultraviolet light was used to catalyze the formation of silica gels made from the hydr… more
Date: April 1, 1998
Creator: Hunt, Arlon J. & Ayers, Michael R.
Partner: UNT Libraries Government Documents Department
open access

A Sealed-Accelerator-Tube Neutron Generator for Boron Neutron Capture Therapy Application

Description: Radio-frequency (RF) driven ion sources are being developed in Lawrence Berkeley National Laboratory (LBNL) for sealed-accelerator-tube neutron generator applications. By using a 2.5-cm-diameter RF-driven multicusp source and a computer designed 100 keV accelerator column, peak extractable hydrogen current exceeding 1 A from a 3-mm-diameter aperture, together with H{sup +} yields over 94% have been achieved. These experimental findings together with recent moderator design will enable one to de… more
Date: June 1, 1998
Creator: Leung, K. N.; Leung, K. N.; Lee, Y.; Verbeke, J. M.; Vurjic, J.; Williams, M. D. et al.
Partner: UNT Libraries Government Documents Department
open access

Lockheed Martin Hanford Corporation systems engineering project management

Description: Lockheed Martin Hanford Corporation is developing and implementing an integrated technical baseline for cleaning up environmental contamination at the Hanford Site in Washington State. The Hanford Site is located in Washington State and has been referred to as one of the largest Environmental Cleanup challenges in the US. It became contaminated with radioactive and dangerous wastes during the 40+ years it was being used to produce weapons grade plutonium in support of the US nuclear weapons pro… more
Date: April 1, 1998
Creator: Baynes, P. A.
Partner: UNT Libraries Government Documents Department
open access

Three dimensional field calculations for a Short Superconducting Dipole for the UCLA Ultra Compact Synchrotron

Description: The Ultra Compact Synchrotron (UCS), proposed for UCLA, is a compact 1.5 GeV electron light source with superconducting magnets to produce X rays with a critical energy of about 10 keV. The design physical length (cold length) for the dipole is 418 mm. The synchrotron requires that a uniform field be produced in a region that is 180 mm wide by 40 mm high by about 380 mm long. The end regions of the dipole should be short compared to the overall length of the dipole field region. A Vobly H type … more
Date: August 1, 1998
Creator: Green, M.A. & Taylor, C.E.
Partner: UNT Libraries Government Documents Department
open access

Fabrication and Test Results of a Prototype, Nb3Sn Superconducting Racetrack Dipole Magnet

Description: A prototype, Nb{sub 3}Sn superconducting magnet, utilizing a racetrack coil design has been built and tested. This magnet represents the first step in a recently implemented program to develop a high field, accelerator quality magnet. This magnet was constructed with coils wound from conductor developed for the ITER project, limiting the magnet to a field of 6-7 Tesla. Subsequent magnets in the program will utilize improved conductor, culminating in a magnet design capable of producing fields a… more
Date: September 1, 1998
Creator: Gourlay, S. A.; Chow, K.; Dietderich, D. R.; Gupta, R.; Hannaford, R.; Harnden, W. et al.
Partner: UNT Libraries Government Documents Department
open access

Instrumentation for the absorbers in the low Beta* Insertions of the LHC

Description: Concepts are examined for the measurement of luminosity, beam-beam separation and transverse beam shape and size using the high flux of forward neutral particles produced at the low {beta}* (high luminosity) interaction points (IP's) of the LHC. At design luminosity 10{sup 34} cm{sup -2}sec{sup -1} the flux of neutrals striking the neutral beam absorbers (TAN) in front of the D2 beam separation dipoles is high enough ({approx} 8 neutrons per bunch crossing with mean energy 2.3 TeV) to allow mea… more
Date: August 1, 1998
Creator: Turner, W.C.
Partner: UNT Libraries Government Documents Department
open access

Measurements of Modulus of Elasticity and Thermal Contraction of Epoxy Impregnated Niobium-Tin and Niobium-Titanium Composites

Description: In the high field magnet program at Lawrence Berkeley National Laboratory, accelerator magnet prototypes are designed with epoxy impregnated niobium-tin and niobium-titanium superconductor. Accurate mechanical property values are essential for magnet mechanical design and prediction of conductor performance. Two key mean property values are measured on coil samples: modulus of elasticity (Young's modulus) and mean thermal contraction. Measurements are made in compression and are conducted in th… more
Date: September 1, 1998
Creator: Chow, K. P. & Millos, G. A.
Partner: UNT Libraries Government Documents Department
open access

Critical Current of Superconducting Rutherford Cable in High Magnetic Fields with Transverse Pressure

Description: For high energy physics applications superconducting cables are subjected to large stresses and high magnetic fields during service. It is essential to know how these cables perform in these operating conditions. A loading fixture capable of applying loads of up to 700 kN has been developed by NHMFL for LBNL. This fixture permits uniform loading of straight cables over a 122 mm length in a split-pair solenoid in fields up to 12 T at 4.2 K. The first results from this system for Rutherford cable… more
Date: September 1, 1998
Creator: Dietderich, D. R.; Scanlan, R. M.; Walsh, R. P. & Miller, J. R.
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

Operations Training Program

Description: No Description Available.
Date: January 1, 1998
Creator: Spata, Michael
Partner: UNT Libraries Government Documents Department
open access

Longitudinal and Transverse Cross Sections in the <sup>1</sup>H(e,e'K<sup>+</sup>)Lambda Reaction

Description: The <sup>1</sup>H(e,e'K<sup>+</sup>)Lambda reaction was studied as a function of the squared four-momentum transfer, Q<sup>2</sup>, and the virtual photon polarizations. The Q<sup>2</sup> dependence of the sigma-L/sigma-T ratio differs significantly from current theoretical predictions. This, combined with the precision of the measurement, implies a need for revision of existing calculations.
Date: August 1, 1998
Creator: Niculescu, Gabriel; Gueye, Paul & Mtingwa, Sekazi
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

Quasifree (e,e'p) Reactions and Proton Propagation in Nuclei

Description: The (e,e'p) reaction was studies on targets of C, Fe, and Au at momentum transfers squared Q{sup 2} of 0.6, 1.3, 1.8 and 3.3 GeV{sup 2} in a region of kinematics dominated by quasifree electron-proton scattering. Missing energy and missing momentum distributions are reasonably well described by plane wave impulse approximation calculations with Q{sup 2} and A dependent corrections that measure the attenuation of the final state protons.
Date: June 1, 1998
Creator: Abbott, David; Ahmidouch, A.; Amatuni, Ts. A.; Armstrong, C.; Arrington, J.; Assamagan, J. A. et al.
Partner: UNT Libraries Government Documents Department
open access

Improved HEPA Filter Technology for Flexible and Rigid Containment Barriers

Description: Safety and reliability in glovebox operations can be significantly improved and waste packaging efficiencies can be increased by inserting flexible, lightweight, high capacity HEPA filters into the walls of plastic sheet barriers. This HEPA filter/barrier technology can be adapted to a wide variety of applications: disposable waste bags, protective environmental barriers for electronic equipment, single or multiple use glovebag assemblies, flexible glovebox wall elements, and room partitions. T… more
Date: July 1, 1998
Creator: Pinson, Paul Arthur
Partner: UNT Libraries Government Documents Department
open access

Cross-industry Performance Modeling: Toward Cooperative Analysis

Description: One of the current unsolved problems in human factors is the difficulty in acquiring information from lessons learned and data collected among human performance analysts in different domains. There are several common concerns and generally accepted issues of importance for human factors, psychology and industry analysts of performance and safety. Among these are the need to incorporate lessons learned in design, to carefully consider implementation of new designs and automation, and the need to… more
Date: October 1, 1998
Creator: Reece, Wendy Jane & Blackman, Harold Stabler
Partner: UNT Libraries Government Documents Department
open access

Destructive versus Nondestructive Assay Comparisons Using the SWEPP Gamma-ray Spectrometer

Description: In support of data quality objectives for the INEEL Stored Waste Examination Pilot Plant (SWEPP) a series of 208-liter (55-gallon) waste drums containing inorganic sludge have been sampled and destructively analyzed. The drums were non-destructively assayed by the SWEPP PAN system and the SWEPP Gamma-Ray Spectrometer (SGRS) prior to sampling. This paper reports some of the conclusions from the destructive versus NDA comparisons, and additionally presents the results of an on-going effort to use… more
Date: November 1, 1998
Creator: Hartwell, John Kelvin; Harker, Yale Deon; Killian, Elmo Wayne & Yoon, Woo Yong
Partner: UNT Libraries Government Documents Department
open access

Imaging of Lamb Waves in Plates for Quantitative Determination of Anisotropy using Photorefractive Dynamic Holography

Description: Anisotropic properties of sheet materials can be determined by measuring the propagation of Lamb waves in different directions. Electromagnetic acoustic transduction and laser ultrasonic methods provide noncontacting approaches that are often desired for application to industrial and processing environments. This paper describes a laser imaging approach utilizing the adaptive property of photorefractive materials to produce a real-time measurement of the antisymmetric Lamb wave mode in all dire… more
Date: June 1, 1998
Creator: Telschow, Kenneth Louis; Deason, Vance Albert; Schley, Robert Scott & Watson, Scott Marshall
Partner: UNT Libraries Government Documents Department
open access

Uncertainty Analysis of Nondestructive Assay Measurements of Nuclear Waste

Description: Regulatory agencies governing the disposal of nuclear waste require that the waste be appropriately characterized prior to disposition. The most important aspect of the characterization process, establishing radionuclide content, is often achieved by nondestructive assay (NDA). For NDA systems to be approved for use in these applications, measurement uncertainty must be established. Standard “propagation of errors” methods provide a good starting point for considering the uncertainty analysis o… more
Date: November 1, 1998
Creator: Blackwood, Larry Gene & Harker, Yale Deon
Partner: UNT Libraries Government Documents Department
open access

Using New Fission Data with the Multi-detector Analysis System for Spent Nuclear Fuel

Description: New experiments using an array of high purity germanium detectors and fast liquid scintillation detectors has been performed to observe the radiation emitted from the induced fission of 235U with a beam of thermal neutrons. The experiment was performed at the Argonne National Laboratory Intense Pulsed Neutron Source. Preliminary observations of the data are presented. A nondestructive analysis system for the characterization of DOE spent nuclear fuel based on these new data is presented.
Date: November 1, 1998
Creator: Cole, Jerald Donald
Partner: UNT Libraries Government Documents Department
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