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Innovative approach to asbestos removal (open access)

Innovative approach to asbestos removal

The most common asbestos materials used at the Savannah River site include: steam pipe insulation; powerhouse boiler insulation; wallboards; roofing materials; and cement products. Asbestos was also found in a number of other materials: aprons; gaskets; laboratory hot pads; and talcum powder used for gloves. Techniques for removal; personnel training; mechanical ventilation; and personnel isolation techniques are described for completing asbestos removal safely and without boiler downtime. (PSB)
Date: January 1, 1984
Creator: Kahal, E J
System: The UNT Digital Library
Electron-beam envelopes and matching for a combined wiggler and alternating-gradient quadrupole channel (open access)

Electron-beam envelopes and matching for a combined wiggler and alternating-gradient quadrupole channel

This work studies the electron-beam envelopes and matching for a combined wiggler and alternating-gradient quadrupole field for a free-electron laser (FEL) that will be operated in the VUV or XUV wavelength region. The quadrupole field is assumed to vary continuously along the symmetry axis. The linearized equations of electron motion are solved analytically by using the two-scale perturbation method for a plane polarized wiggler. The electron-beam envelopes and the envelope equations, as well as the matching conditions in phase space, are obtained from the electron trajectories. A comparison with the numerical solution is presented.
Date: January 1, 1985
Creator: Wang, T. F. & Cooper, R. K.
System: The UNT Digital Library
Technique for dynamic range reduction for Landsat ratio images (open access)

Technique for dynamic range reduction for Landsat ratio images

The LANDSAT ratio image, obtained by dividing one MSS band by another on a point-by-point basis, has become an established tool for geological applications over the past several years. Display of such images can be difficult since the dynamic range can extend from zero to infinity. A scheme for dynamic range reduction, based on a mathematical model of the multispectral image, is presented. It can be implemented on stand-alone digital image processing systems as well as general purpose computers. This technique also has potential application in machine classification of geological data. Digital image processing examples are presented in which this new scheme is compared with other commonly used techniques for dynamic range reduction.
Date: January 1, 1978
Creator: Wecksung, G.W. & Breedlove, J.R. Jr.
System: The UNT Digital Library
Total hadron cross section, new particles, and muon electron events in e/sup +/e/sup -/ annihilation at SPEAR (open access)

Total hadron cross section, new particles, and muon electron events in e/sup +/e/sup -/ annihilation at SPEAR

The review of total hadron electroproduction cross sections, the new states, and the muon--electron events includes large amount of information on hadron structure, nine states with width ranging from 10's of keV to many MeV, the principal decay modes and quantum numbers of some of the states, and limits on charm particle production. 13 references. (JFP)
Date: January 1, 1976
Creator: Richter, B.
System: The UNT Digital Library
Automatic program timing profiles with FTN4 (open access)

Automatic program timing profiles with FTN4

Design of a scheme for producing execution timing profiles of FORTRAN programs automatically is proposed with a recommendation to implement it as an option to the compiler. An experimental implementation on the LBL 7600 is also described. 1 figure.
Date: September 1, 1980
Creator: Friedman, R.
System: The UNT Digital Library
Construction and testing of the Mirror Fusion Test Facility magnets (open access)

Construction and testing of the Mirror Fusion Test Facility magnets

This paper describes the construction and testing of the Mirror Fusion Test Facility superconducting magnet set. Construction of the first Yin Yang magnet was started in 1978. And although this particular magnet was later modified, the final construction of these magnets was not completed until 1985. When completed these 42 magnets weighed over 1200 tonnes and had a maximum stored energy of approximately 1200 MJ at full field. Together with power supplies, controls and liquid nitrogen radiation shields the cost of the fabrication of this system was over $100M. General Dynamics/Convair Division was responsible for the system design and the fabrication of 20 of the magnets. This contract was the largest single procurement action at the Lawrence Livermore National Laboratory. During the PACE acceptance tests, the 26 major magnets were operated at full field for more than 24 hours while other MFTF subsystems were tested. From all of the data, the magnets operated to the performance specifications. For physics operation in the future, additional helium and nitrogen leak checking and repair will be necessary. In this report we will discuss the operation and testing of the MFTF Magnet System, the world's largest superconducting magnet set built to date. The topics …
Date: August 1, 1986
Creator: Kozman, T.; Shimer, D.; VanSant, J. & Zbasnik, J.
System: The UNT Digital Library
Calorimetric and optical beam diagnostics on the LBL 120-keV neutral beam test facility (open access)

Calorimetric and optical beam diagnostics on the LBL 120-keV neutral beam test facility

The 120-keV Neutral Beam Test Facility at LBL is fitted with several types of instrumentation to determine the properties of the 10- to 15-A hydrogen and deuterium beams produced in this facility. These include a neutral particle dump for measuring the temperature profile generated by the beam, and a fixed and a moveable ion dump to measure the temperature profiles generated by the various ion components after they have been swept out of the neutral beam by a bending magnet. These several dumps provide enough information to determine the power density profiles and divergences of the neutral beam and the various ion beams for comparison with theoretical calculations, the beam composition, and the neutralization efficiency. The optical beam diagnostic consists of a high-resolution spectrometer coupled with a commercial optical multichannel analyzer. These instruments analyze Doppler-shifted optical radiation from the moving neutral atoms in the beam. Analysis of data so obtained provides the aiming directions and divergences of the various energy components in the neutral beam, as well as the beam composition.
Date: October 1, 1977
Creator: Burrell, C. F.; Cooper, W. S.; Steele, W. F. & Smith, R. R.
System: The UNT Digital Library
Design and operation of an inert gas facility for thermoelectric generator storage (open access)

Design and operation of an inert gas facility for thermoelectric generator storage

While the flight hardware is protected by design from the harsh environments of space, its in-air storage often requires special protection from contaminants such as dust, moisture and other gases. One of these components, the radioisotope thermoelectric generator (RTG) which powers the missions, was deemed particularly vulnerable to pre-launch aging because the generators remain operational at core temperatures in excess of 1000 degrees centigrade throughout the storage period. Any oxygen permitted to enter the devices will react with thermally hot components, preferentially with molybdenum in the insulating foils, and with graphites to form CO/CO{sub 2} gases which are corrosive to the thermopile. It was important therefore to minimize the amount of oxygen which could enter, by either limiting the effective in-leakage areas on the generators themselves, or by reducing the relative amount of oxygen within the environment around the generators, or both. With the generators already assembled and procedures in place to assure minimal in-leakage in handling, the approach of choice was to provide a storage environment which contains significantly less oxygen than normal air. 2 refs.
Date: January 1, 1990
Creator: Goebel, C. J.
System: The UNT Digital Library
Microwave separation of organic chemicals from mixed hazardous waste (open access)

Microwave separation of organic chemicals from mixed hazardous waste

The feasibility of utilizing the differential heating characteristics of microwave energy (MW) to aid in the chemical extraction and separation process of hazardous organic compounds from mixed hazardous waste, was studied at the INEL. The long-term objective of this work was to identify a practical method of separating or enhancing the separation process of organic hazardous waste components from mixed waste using microwave (MW) frequency radiation. Methods using MW energy for calcination, solidification, and drying of radioactive waste from nuclear facilities is becoming more attractive. In order to study the effectiveness of MW heating, samples of several organic chemicals simulating those which may be found at the Radioactive Waste Management Complex at the INEL were exposed to MW energy. Vapor collection and analysis was performed as a function of time, signal frequency, and MW power throughout the process. Signal frequencies ranging from 900 MHz t 8000 MHz were used. Although the signal frequency bandwidth of the selectivity was quite broad, for the material tested an indication of the frequency dependence in the selectivity of MW heating was given. Greater efficiency in terms of energy used and time required was observed. The relatively large electromagnetic field intensities generated at the resonant …
Date: January 1, 1992
Creator: Anderson, A. A. & Albano, R. K.
System: The UNT Digital Library
Pseudorapidity distributions and correlations in central sup 16 O interactions at 200 A GeV (open access)

Pseudorapidity distributions and correlations in central sup 16 O interactions at 200 A GeV

Whether or not adequate energy densities for a transition to the Quark-Gluon Plasma (QGP) phase are possible in {sup 16}O and {sup 32}S induced reactions is still an open question. Before unambiguous signals can be identified it is necessary to understand the background upon which the expected QGP signatures can be sought. An important aim of early experiments in this new energy density regime is thus to understand the process of hadronization in a nuclear environment. In any discussion of high energy nucleus-nucleus collisions formation time is an important feature. If, for example, the final state particles are produced instantaneously in a bound hadron-nucleon collision, all these particles will have a chance to reinteract inside the nuclear medium. If, on the other hand, the formation time is long, i.e., longer than the nuclear diameter, the energy flux will stay together as a unit throughout its passage through the target nucleus. While these extreme cases are clearly unrealistic, one expects interaction parameters such as the multiplicity and pseudorapidity distributions to be sensitive functions of the formation time. Here we present results on charged hadron production in an experiment using tracking detectors with the highest possible spatial resolution: emulsion chambers. A sample …
Date: January 1, 1988
Creator: Wilkes, R. J.
System: The UNT Digital Library
Modeling studies on the precipitation of Kr after implantation into metals (open access)

Modeling studies on the precipitation of Kr after implantation into metals

A rate-theory approach is applied to interpreting observations on the precipitation of Kr injected into Ni at temperatures between 25 and 560/degree/C. At temperatures of 400/degree/C or higher, the implanted Kr precipitates evolve into a bi-modal size distribution containing small solid precipitates and an additional population of larger, faceted bubbles. The calculations explore the dependence of the observed bi-modal distribution on the maximum size of the solid Kr precipitates and the effect of this dependence on bubble mobility. The analysis suggests that during the irradiation, whereas the large bubbles move by surface diffusion, the solid Kr precipitates are immobile. The relevance of the Kr-Ni interaction on the solid Kr precipitates size cutoff is discussed. 18 refs., 8 figs., 2 tabs.
Date: February 1, 1988
Creator: Rest, J.
System: The UNT Digital Library
Model for the control of dissolved manganese in the interstitial waters of Chesapeake Bay (open access)

Model for the control of dissolved manganese in the interstitial waters of Chesapeake Bay

None
Date: January 1, 1975
Creator: Holdren, G. R., Jr.; Bricker, O. P., III & Matisoff, G.
System: The UNT Digital Library
EPICS System: An Overview (open access)

EPICS System: An Overview

This paper presents an overview of the EPICS control system at FERMILAB. EPICS is a distributed, multi-user, interactive system for the control and monitoring of particle beamlines at a high-energy experimental physics laboratory. The overview discusses the operating environment of the control system, the requirements which determined the design decisions, the hardware and software configurations, and plans for the future growth and enhancement of the present system. This paper is the first of three related papers on the EPICS system. The other two cover (1) the system structure and user interface and (2) RSX implementation issues.
Date: February 1, 1984
Creator: Bartlett, J. F.; Bobbitt, J. S.; Kramper, B. J.; Lahey, T. E.; MacKinnon, B. A. & West, R. E.
System: The UNT Digital Library
Catalytic steam gasification of bagasse for the production of methanol (open access)

Catalytic steam gasification of bagasse for the production of methanol

Pacific Northwest Laboratory (PNL) tested the catalytic gasification of bagasse for the production of methanol synthesis gas. The process uses steam, indirect heat, and a catalyst to produce synthesis gas in one step in fluidized bed gasifier. Both laboratory and process development scale (nominal 1 ton/day) gasifiers were used to test two different catalyst systems: (1) supported nickel catalysts and (2) alkali carbonates doped on the bagasse. This paper presents the results of laboratory and process development unit gasification tests and includes an economic evaluation of the process. 20 references, 6 figures, 9 tables.
Date: December 1, 1983
Creator: Baker, E.G. & Brown, M.D.
System: The UNT Digital Library
Geothermal waste treatment biotechnology: Progress and advantages to the utilities (open access)

Geothermal waste treatment biotechnology: Progress and advantages to the utilities

Development of biotechnology for treatment of geothermal residual waste is aimed at the application of low-cost biochemical processes for the surface treatment and disposal of residual geothermal sludges. These processes, in addition to the lowering of disposal cost, are designed to be environmentally acceptable. Recent studies at Brookhaven National Laboratory (BNL) have shown that optimization of several process variables results in fast rates (<24h) of metal removal from residual sludges at acidic pH ({minus}1--2). Optimization of the process variables also enables the removal of radioactive isotopes. In addition, the aqueous phase produced during the bioprocessing which contains solubilized metals can be further treated in a manner which precipitates out the metals and renders the aqueous effluent toxic metal free. In this paper, the various process options will be discussed in terms of biotreatment variables. Chemical composition before and after biotreatment will also be discussed in terms of long-range effects, quality assurance and potential disposal costs.
Date: March 1, 1992
Creator: Premuzic, E.T.; Lin, M.S. & Jin, J.
System: The UNT Digital Library
Alignment and focusing device for a multibeam laser system (open access)

Alignment and focusing device for a multibeam laser system

Large inertial confinement fusion laser systems have many beams focusing on a small target. The Antares system is a 24-beam CO/sub 2/ pulse laser. To produce uniform illumination, the 24 beams must be individually focused on (or near) the target's surface in a symmetric pattern. To assess the quality of a given beam, we will locate a Smartt (point diffraction) interferometer at the desired focal point and illuminate it with an alignment laser. The resulting fringe pattern shows defocus, lateral misalignment, and beam aberrations; all of which can be minimized by tilting and translating the focusing mirror and the preceding flat mirror. The device described in this paper will remotely translate the Smartt interferometer to any position in the target space and point it in any direction using a two-axis gimbal. The fringes produced by the interferometer are relayed out of the target vacuum shell to a vidicon by a train or prisms. We are designing four separate snap-in heads to mount on the gimbal; two of which are Smartt interferometers (for 10.6 ..mu..m and 633 nm) and two for pinholes, should we wish to put an alignment beam backwards through the system.
Date: January 1, 1980
Creator: Sweatt, W.C.
System: The UNT Digital Library
Physics of antimatter-matter reactions for interstellar propulsion (open access)

Physics of antimatter-matter reactions for interstellar propulsion

At the stage of the antiproton-nucleon annihilation chain of events relevant to propulsion the annihilation produces energetic charged pions and gamma rays. If annihilation occurs in a complex nucleus, protons, neutrons, and other nuclear fragments are also produced. The charge, number, and energy of the annihilation products are such that annihilation rocket engine concepts involving relatively low specific impulse (I/sub sp/ approx. = 1000 to 2000 s) and very high I/sub sp/ (3 x 10/sup 7/ s) appear feasible and have efficiencies on the order of 50% for annihilation energy to propulsion energy conversion. At I/sub sp/'s of around 15,000 s, however, it may be that only the kinetic energy of the charged nuclear fragments can be utilized for propulsion in engines of ordinary size. An estimate of this kinetic energy was made from known pieces of experimental and theoretical information. Its value is about 10% of the annihilation energy. Control over the mean penetration depth of protons into matter prior to annihilation is necessary so that annihilation occurs in the proper region within the engine. Control is possible by varying the antiproton kinetic energy to obtain a suitable annihilation cross section. The annihilation cross section at low energies is …
Date: August 22, 1986
Creator: Morgan, D.L. Jr.
System: The UNT Digital Library
HTGR safety philosophy (open access)

HTGR safety philosophy

The accident at the Three Mile Island has focused public attention on reactor safety. Many public figures advocate a safer method of generating nuclear electricity for the second nuclear era in the US. The paper discusses the safety philosophy of a concept deemed suitable for this second nuclear era. The HTGR, in the course of its evolution, included safety as a significant determinant in design philosophy. This is particularly evident in the design features which provide inherent safety. Inherent features cause releases from a wide spectrum of accident conditions to be low. Engineered features supplement inherent features. The significance of HTGR safety features is quantified and order-of-magnitude type of comparisons are made with alternative ways of generating electricity.
Date: August 1, 1980
Creator: Joskimovic, V. & Fisher, C.R.
System: The UNT Digital Library
Bumps and poles in the S-matrix: A systematic study of 0 sup ++ and 2 sup ++ mesons plus a molecule approach to the E(1420) in the K K. pi. system (open access)

Bumps and poles in the S-matrix: A systematic study of 0 sup ++ and 2 sup ++ mesons plus a molecule approach to the E(1420) in the K K. pi. system

The goal of Hadron Spectroscopy is to find the spectrum of states formed by color singlet arrangements of quarks and gluons. Ideally these spectral states are associated with poles of the scattering matrix of hadrons which are the decay channels of the states. For example the {rho} meson is the lowest q{bar q} s-wave, spin one color singlet state and decays into {pi}{sup +}{pi}{sup -}. Since the {rho}decays in a relative p-wave, one finds the {rho} pole in the I = 1 p-wave {pi}{pi} phase shifts. There are forces between quarks and gluons which do not manifest themselves as true resonances and thus cannot be described by a Breit-Wigner pole. I will give some examples that are not Breit-Wigner poles of the scattering matrix but are important bumps in meson production. 22 refs., 10 figs.
Date: November 16, 1989
Creator: Longacre, R. S.
System: The UNT Digital Library
In-Vitro and in-Vivo Characterization of Ruthenium-Bleomycin Compared to Cobalt- and Copper-Bleomycin (open access)

In-Vitro and in-Vivo Characterization of Ruthenium-Bleomycin Compared to Cobalt- and Copper-Bleomycin

Bleomycin (BLM) has undergone extensive investigation both as a cancer chemotherapeutic agent, and as a carrier for radionuclides for tumor imaging. The available methods or the radionuclides used, however, have had limited effectiveness. Although labeling of BLM with /sup 103/Ru has been reported earlier, we carried out a study to develop a more reproducible method of labeling particularly for use with Brookhaven Linac Isotope Producer produced /sup 97/Ru. Ruthenium-97 has favorable physical properties that make it ideal for imaging applications: decay by electron capture; ..gamma.. 216 keV, 85%; t/sub 1/2/ 2.9 d. A novel method based on the reduction of Ru/sup 3 +/ to Ru/sup 2 +/ using stannous chloride was investigated for labeling BLM with /sup 97/Ru and/or /sup 103/Ru. In-vitro and in vivo comparisons of the product(s) with /sup 57/Co and /sup 67/Cu-labeled BLM were also carried out. 4 refs., 3 tabs.
Date: January 1, 1986
Creator: Shao, H. S.; Meinken, G. E.; Srivastava, S. C.; Slosman, D.; Sacker, D. F.; Som, P. et al.
System: The UNT Digital Library
Radiation dosimetry through spectral definition (open access)

Radiation dosimetry through spectral definition

We have developed a fieldable instrumentation system for determining from measured flux spectra, both the neutron and gamma ray dose rate distributions associated with radioactive sources. This system includes the sensors, the computer-based data acquisition and analysis hardware, and the requisite software for unfolding the sensor response functions to obtain the flux spectra, and for folding the resultant flux spectra with appropriate flux spectrum-to-dose conversion factors. We use bismuth germanate scintillators that have experimentally measured and analytically interpolated response functions to determine the gamma ray flux spectra, and a suite of neutron sensors, based on proton recoil and /sup 3/He capture, to determine the neutron flux spectra. In addition, gamma ray peak identification is done using HPGe sensors. We describe the equipment and procedures and present some recent results. 10 refs., 15 figs.
Date: January 1, 1985
Creator: Dowdy, E. J.; Moss, C. E.; Robba, A. A.; Evans, A. E.; Lucas, M. C.; Shunk, E. R. et al.
System: The UNT Digital Library
A theoretical prediction of critical heat flux in subcooled pool boiling during power transients (open access)

A theoretical prediction of critical heat flux in subcooled pool boiling during power transients

Understanding and predicting critical heat flux (CHF) behavior during steady-state and transient conditions are of fundamenatal interest in the design, operation, safety of boiling and two-phase flow devices. This paper discusses the results of a comprehensive theoretical study made specifically to model transient CHF behavior in subcooled pool boiling. This study is based upon a simplified steady-state CHF model in terms of the vapor mass growth period. The results obtained from this theory indicate favorable agreement with the experimental data from cylindrical heaters with small radii. The statistical nature of the vapor mass behavior in transient boiling also is considered and upper and lower limits for the current theory are established. Various factors that affect the discrepancy between the data and the theory are discussed.
Date: January 1, 1988
Creator: Pasamehmetoglu, K. O.; Nelson, R. A. & Gunnerson, F. S.
System: The UNT Digital Library
Transverse spin observables in chromodynamics (open access)

Transverse spin observables in chromodynamics

Quantum Chromodynamics confronts a harsh series of tests in the attempt to formulate a comprehensive approach to the calculation of transverse spin observables. The basic obstacles to understanding transverse spin can be illustrated by considering the transverse structure function g{sub T}(x, Q{sup 2}) = g{sub 1}(x, Q{sup 2}) + g{sub 2}(x, Q{sup 2}), extracted from deep-inelastic scattering using a polarized lepton and a polarized proton. The inadequacy of the transverse-spin basis for quarks and gluons found there suggests a new approach to the problems of single-spin observables in large-transverse-momentum processes. This approach, presented earlier for single spin production asymmetries, is discussed here. It is shown that the mechanism can also lead to baryon polarization effects at large P{sub T}. 14 refs.
Date: December 1, 1989
Creator: Sivers, D.
System: The UNT Digital Library
Neutron scattering from solutions: the hydration of lanthanide and actinide ions (open access)

Neutron scattering from solutions: the hydration of lanthanide and actinide ions

The neutron scattering difference method is described and applied to investigations of the aqua rare-earth ions, Nd/sup 3 +/ and Dy/sup 3 +/. Metal-water distances and hydration numbers have been unambiguously determined for these ions' inner coordination spheres. The values of the hydration number, n, of 8.5 +- 0.2 for Nd/sup 3 +/ and 7.4 +- 0.5 for Dy/sup 3 +/, directly support the claim of Spedding et al. that n decreases by one unit across the lanthanide series. The possible application of this method to actinide ions in solution is also discussed. 7 refs., 4 figs.
Date: January 1, 1985
Creator: Hahn, R.L.; Narten, A.H. & Annis, B.K.
System: The UNT Digital Library