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The multipulse Thomson scattering diagnostic on the DIII-D tokamak

Description: This paper describes the design and operation of a 40-spatial channel Thomson scattering system that uses multiple 20 Hz Nd:YAG lasers to measure the electron temperature and density profiles periodically throughout an entire plasma discharge. Interference filter polychromators disperse the scattered light which is detected by silicon avalanche photodiodes. The measurable temperature range from 10 eV to 20 keV and the minimum detectable density is about 2 {times} 10{sup 18} m{sup {minus}3}. Laser control and data acquisition are performed in real-time by a VME-based microcomputer. Data analysis is performed by a MicroVAX 3400. Unique features of this system include burst mode'' operation, where multiple lasers are fired in rapid succession (< 10 KHz), real-time analysis capability, and laser beam quality and alignment monitoring during plasma operation. Results of component testing, calibration, and plasma operation are presented. 8 refs. 6 figs.
Date: September 1, 1991
Creator: Carlstrom, T. N.; Campbell, G. L.; DeBoo, J. C.; Evanko, R. G.; Evans, J.; Greenfield, C. M. et al.
Partner: UNT Libraries Government Documents Department
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Two exercises in supersymmetry: a low-energy supergravity model and free string field theory

Description: The new features of a supersymmetric standard model in the presence of heavy families are studied. The minimal set of Higgs fields, the desert between the electroweak and the grand unification scale and perturbative values of the dimensionless parameters throughout this region are assumed. Using the numerical as well as the approximate analytic solution of the renormalization group equations, the evolution of all the parameters of the theory are studied in the case of large Yukawa couplings for the fourth family. The desired spontaneous symmetry breaking of the electroweak symmetry takes place only for a rather unnatural choice of the initial values of certain mass parameters at the grand unification scale. If it is gravitino mass smaller than 200 GeV the vacuum expectation values of the Higgs fields emerge necessarily in an interplay of the tree level Higgs potential and its quantum corrections and are approximately equal. The qurak masses of the fourth family are roughly 135 GeV, while the mass of the fourth charged lepton has an upper bound of 90 GeV. Further characteristic features of this scenario are one light neutral Higgs field of mass 50 GeV and gluino masses below 75 GeV. If the gravitino mass is higher than 200 GeV one obtains a scaled up version of the well-known three family, heavy top scenario with quark masses between 40 and 205 GeV and all superparticle masses heavier than 150 GeV except the photino, gluino, one chargino and one neutralino. The gauge-invariant theory of the free bosonic open string is generalized to treat closed strings and superstrings. All of these theories can be written as theories of string differential forms defined on suitable spaces. All of the bosonic theories have exactly the same structure; the Ramond theory takes an analogous first-order form. We show explicitly, how to …
Date: September 1, 1986
Creator: Preitschopf, C.R.
Partner: UNT Libraries Government Documents Department
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Assessment of research and development (R and D) needs in ammonia safety and environmental control

Description: This report characterizes the ammonia industry operations, reviews current knowledge of ammonia release and subsequent impacts, summarizes the status of release prevention and control methods and identify research and development needs for safety and environmental control. Appendices include: accidental spills and human exposure; adiabatic mixing of liquid nitrogen and air; fire and explosion hazards; and environmental impact rating tables. (PSB)
Date: September 1, 1981
Creator: Brenchley, D.L.; Athey, G.F. & Bomelburg, H.J.
Partner: UNT Libraries Government Documents Department
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Correlation of alluvial deposits at the Nevada Test Site

Description: Because characteristics of rock layers and problems in drilling must be studied before radioactive waste can be safely contained, an evaluation was made of methods for correlating alluvial deposits at Yucca Flat of the Nevada Test Site (NTS). Although correlation of Tertiary volcanic tuff beds at the NTS has been successfully achieved, correlation of stratigraphic zones in the overlying alluvium has posed technical difficulties. We have evaluated several methods for correlating alluvial deposits from drillholes, including electric resistivity logs (E logs), visual examination of sidewall samples and comparison of their carbonate (CO/sub 2/) content, downhole stereo photography for identifying debris flow deposits, caliche age-dating, and specific yield and permeability measurements of deposits. For predicting the thickness of zones having similar physical properties in the alluvium, E log measurements were found to be the most useful of these methods.
Date: September 30, 1977
Creator: Grothaus, B. & Howard, N.
Partner: UNT Libraries Government Documents Department
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Nuclear facility decommissioning and site remedial actions. Volume 6. A selected bibliography

Description: This bibliography of 683 references with abstracts on the subject of nuclear facility decommissioning, uranium mill tailings management, and site remedial actions is the sixth in a series of annual reports prepared for the US Department of Energy's Remedial Action Programs. Foreign as well as domestic literature of all types - technical reports, progress reports, journal articles, conference papers, symposium proceedings, theses, books, patents, legislation, and research project descriptions - has been included. The bibliography contains scientific (basic research as well as applied technology), economic, regulatory, and legal literature pertinent to the US Department of Energy's remedial action program. Major chapters are: (1) Surplus Facilities Management Program; (2) Nuclear Facilities Decommissioning; (3) Formerly Utilized Sites Remedial Action Program; (4) Facilities Contaminated with Natural Radioactivity; (5) Uranium Mill Tailings Remedial Action Program; (6) Grand Junction Remedial Action Program; (7) Uranium Mill Tailings Management; (8) Technical Measurements Center; and (9) General Remedial Action Program Studies. Chapter sections for chapters 1, 2, 5, and 7 include Design, Planning, and Regulations; Environmental Studies and Site Surveys; Health, Safety, and Biomedical Studies; Decontamination Studies; Dismantlement and Demolition; Site Stabilization and Reclamation; Waste Disposal; Remedial Action Experience; and General Studies. The references within each chapter or section are arranged alphabetically by leading author. References having no individual author are arranged by corporate affiliation or by publication description.
Date: September 1, 1985
Creator: Owen, P. T.; Michelson, D. C. & Knox, N. P.
Partner: UNT Libraries Government Documents Department
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Prospects of physics at CDF with the SVX

Description: During next physics run CDF will strongly enhance its heavy flavor tagging capabilities with the installation of a silicon vertex detector (SVX), that will allow precise measurements of secondary decay vertices in the plane transverse to the beam (impact parameter resolution {approx equal} 12 {mu}m). We expect this detector to have a significant impact on b-physics (c{tau}{sub B} {approx equal} 350 {mu}m) and top search. In the following we will discuss CDF prospects for top search and for CP violation asymmetry measurements in the B-sector. 16 refs., 5 figs., 1 tabs.
Date: September 1, 1991
Creator: Dell'Agnello, S.
Partner: UNT Libraries Government Documents Department
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Review of tribological sinks in six major industries

Description: Friction and material wear occur throughout all industries and are involved in many processes within each industry. These conditions make assessing tribological activity overall in industry very complex and expensive. Therefore, a research strategy to obtain preliminary information on only the most significant industrial tribological sinks was defined. The industries examined were selected according to both the magnitude of overall energy consumption (particularly machine drive) and the known presence of significant tribological sinks. The six industries chosen are as follows: mining, agriculture, primary metals, chemicals/refining, food, and pulp and paper. They were reviewed to identify and characterize the major tribology sinks. It was concluded that wear losses are greater than friction losses, and that reducing wear rates would improve industrial productivity.
Date: September 1, 1985
Creator: Imhoff, C. H.; Brown, D. R.; Hane, G. J.; Hutchinson, R. A.; Erickson, R.; Merriman, T. et al.
Partner: UNT Libraries Government Documents Department
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HVDC-AC system interaction from AC harmonics. Volume 1. Harmonic impedance calculations. Final report

Description: Improved methods are needed to characterize ac system harmonic behavior for ac filter design for HVDC systems. The purpose of this General Electric Company RP1138 research is to evaluate the present filter design practice and to investigate methods for calculating system harmonic impedances. An overview of ac filter design for HVDC systems and a survey of literature related to filter design have been performed. Two methods for calculating system harmonic impedances have been investigated. In the measurement method, an instrumentation system for measuring system voltage and current has been assembled. Different schemes of using the measurements to calculate system harmonic impedances have been studied. In the analytical method, a procedure to include various operating conditions has been proposed. Computer programs for both methods have been prepared, and the results of the measurement and analytical methods analyzed. A conclusion of the project is that the measurement and analytical methods both provided reasonable results. There are correlations between the measured and analytical results for most harmonics, although there are discrepancies between the assumptions used in the two methods. A sensitivity approach has been proposed to further correlate the results. From the results of the analysis, it is recommended that both methods should be tested further. For the measurement method, more testing should be done to cover different system operating conditions. In the analytical method, more detailed models for representing system components should be studied. In addition, alternative statistical and sensitivity approaches should be attempted.
Date: September 1, 1982
Creator: Breuer, G D; Chow, J H; Lindh, C B; Miller, N W; Numrich, F H; Price, W W et al.
Partner: UNT Libraries Government Documents Department
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Schemes for anti pp interactions at ISABELLE

Description: Various schemes for obtaining anti pp interactions are outlined, and the luminosities obtainable for each case calculated. In the simplest realistic case, a luminosity of 1.3 x 10/sup 29/ is obtained with a 13 hour filling time. The addition of special rf systems in both the AGS and ISABELLE give a scheme with luminosity 8 x 10/sup 29/ in 6 hours. The use of stochastic cooling to stack raises the luminosity to as high as 10/sup 31/ but the filling time is then 68 hours. Finally a scheme is considered that uses a special 30 GeV capture ring. With this, a luminosity of 10/sup 31/ could be achieved after 20 hours, or higher if a larger filling time were acceptable. Further gains could be made if a smaller proton spot on the target is used but a simple calculation suggests that even the spot size assumed may explode the target too fast.
Date: September 8, 1977
Creator: Palmer, Robert B.
Partner: UNT Libraries Government Documents Department
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ETRANS: an energy transport system optimization code for distributed networks of solar collectors

Description: The optimization code ETRANS was developed at the Pacific Northwest Laboratory to design and estimate the costs associated with energy transport systems for distributed fields of solar collectors. The code uses frequently cited layouts for dish and trough collectors and optimizes them on a section-by-section basis. The optimal section design is that combination of pipe diameter and insulation thickness that yields the minimum annualized system-resultant cost. Among the quantities included in the costing algorithm are (1) labor and materials costs associated with initial plant construction, (2) operating expenses due to daytime and nighttime heat losses, and (3) operating expenses due to pumping power requirements. Two preliminary series of simulations were conducted to exercise the code. The results indicate that transport system costs for both dish and trough collector fields increase with field size and receiver exit temperature. Furthermore, dish collector transport systems were found to be much more expensive to build and operate than trough transport systems. ETRANS itself is stable and fast-running and shows promise of being a highly effective tool for the analysis of distributed solar thermal systems.
Date: September 1, 1980
Creator: Barnhart, J.S.
Partner: UNT Libraries Government Documents Department
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Physical simulations of cavity closure in a creeping material

Description: The finite element method has been used extensively to predict the creep closure of underground petroleum storage cavities in rock salt. Even though the numerical modeling requires many simplifying assumptions, the predictions have generally correlated with field data from instrumented wellheads, however, the field data are rather limited. To gain an insight into the behavior of three-dimensional arrays of cavities and to obtain a larger data base for the verification of analytical simulations of creep closure, a series of six centrifuge simulation experiments were performed using a cylindrical block of modeling clay, a creeping material. Three of the simulations were conducted with single, centerline cavities, and three were conducted with a symmetric array of three cavities surrounding a central cavity. The models were subjected to body force loading using a centrifuge. For the single cavity experiments, the models were tested at accelerations of 100, 125 and 150 g's for 2 hours. For the multi-cavity experiments, the simulations were conducted at 100 g's for 3.25 hours. The results are analyzed using dimensional analyses. The analyses illustrate that the centrifuge simulations yield self-consistent simulations of the creep closure of fluid-filled cavities and that the interaction of three-dimensional cavity layouts can be investigated using this technique.
Date: September 1, 1985
Creator: Sutherland, H.J. & Preece, D.S.
Partner: UNT Libraries Government Documents Department
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Stark broadening of isolated lines from high-Z emitters in dense plasmas

Description: The joint distribution of the electric microfield and its longitudinal derivative is required for the calculation of line profiles for the He-like ions in very dense plasmas. We used a molecular dynamics code to compute exact distributions in single- and multi-component plasmas, and then we investigated various analytical approximations to these results. We found that a simplified, two-nearest-neighbor scheme leads to surprisingly accurate distribution functions. Our results are illustrated by sample profiles for Ne/sup +8/ and Ar/sup +16/ resonance lines.
Date: September 1, 1980
Creator: Weisheit, J.C. & Pollock, E.L.
Partner: UNT Libraries Government Documents Department
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Photoinduced Charge Separation by Polymer-Bound Chromophores

Description: This project has examined the photodynamic behavior of water-soluble polymers that have covalently linked hydrophobic chromophores spaced along the chains. These polymeric systems have been examined for photoinduced charge separation with electron-accepting ions having different total charge. Focus has been on the excited singlet (S{sub 1}) state formed by laser flash absorption. The effects of pH and ionic strength -- factors that govern the conformational nature of the polymer in solution -- have been studied. A second major effort has been to study photoinduced redox processes involving excited states of water-soluble variants of anthracene and acridine. 27 refs., 16 figs., 2 tabs.
Date: September 1, 1991
Creator: Rodgers, M. A. J.
Partner: UNT Libraries Government Documents Department
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Physical fitness training reference manual for security force personnel at fuel cycle facilities possessing formula quantities of special nuclear materials

Description: The recommendations contained throughout this NUREG are being provided to the Nuclear Regulatory Commission (NRC) as a reference manual which can be used by licensee management as they develop a program plan for the safe participation of guards, Tactical Response Team members (TRTs), and all other armed response personnel in physical fitness training and in physical performance standards testing. The information provided in this NUREG will help licensees to determine if guards, TRTs, and other armed response personnel can effectively perform their normal and emergency duties without undue hazard to themselves, to fellow employees, to the plant site, and to the general public. The recommendations in this NUREG are similar in part to those contained within the Department of Energy (DOE) Medical and Fitness Implementation Guide which was published in March 1991. The guidelines contained in this NUREG are not requirements, and compliance is not required. 25 refs.
Date: September 1, 1991
Creator: Arzino, P. A.; Caplan, C. S. & Goold, R. E. (California State Univ., Hayward, CA (United States). Foundation)
Partner: UNT Libraries Government Documents Department
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State of the art of pressurized fluidized bed combustion systems

Description: This report was prepared at the request of the Tennessee Valley Authority (TVA) to clarify the development status of the pressurized fluidized bed combustor (PFBC) and to place in perspective the problems which are yet to be solved before commercialization of the concept is practical. This report, in essence, supersedes the interim report published in 1979, Assessment of the State of the Art of Pressurized Fluidized Bed Combustion Systems. A brief overview of the PFBC concept is included citing potential advantages and disadvantages relative to atmospheric fluidized bed combustion (AFBC) and conventional pulverized coal plants. A survey of existing and developing PFBC experimental facilities is presented in some detail which includes the major accomplishments at the respective facilities. Recent data on plant emissions, turbine/gas cleanup systems, and overall efficiency are provided. Findings of several design studies are also discussed. The results of recent gas turbine and cascade tests have been encouraging although the full assessment of the accomplishments have not been made. The delay in construction of the Grimethorpe plant causes further delay in proof-testing full-size, rotating turbomachinery. Several parameters are recommended for further assessment in design studies including: (1) effect of turbine life on cost of power; and (2) effect of reduced gas turbine inlet temperature and pressure on cost of power.
Date: September 1, 1980
Creator: Graves, R.L.
Partner: UNT Libraries Government Documents Department
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Continuum damping of low-n toroidicity-induced shear Alfven eigenmodes

Description: The effect of resonant continuum damping is investigated for the low-mode-number, toroidicity-induced, global shear Alfven eigenmodes, which can be self-excited by energetic circulating alpha particles in an ignited tokamak plasma. Resonant interaction with the shear Alfven continuum is possible for these eigenmodes, especially near the plasma periphery, leading to significant dissipation, which is typically larger than direct bulk plasma dissipation rates. Two perturbation methods are developed for obtaining the Alfven resonance damping rate from the ideal fluid zeroth-order shear Alfven eigenvalue and eigenfunction. In both methods the real part of the frequency is estimated to zeroth order, and the imaginary part, which includes the damping rate, is then obtained by perturbation theory. One method, which is applicable when the eigenfunction is nearly real, can readily be incorporated into general MHD codes. In the second method, the zeroth-order eigenfunctions may be complex; however, the application of this method to general MHD codes needs more detailed development. Also, an analytical estimate is found for the next-order real frequency shift of the fluid global Alfven mode. Analytical and numerical studies of this continuum damping effect indicate that it can substantially reduce the alpha particle-induced growth rate. Thus, either it is possible to prevent instability, or if unstable, to use the Alfven resonance damping to estimate the saturation amplitude level predicted from quasilinear theory. 44 refs., 13 figs., 1 tab.
Date: September 1, 1991
Creator: Berk, H.L.; Van Dam, J.W.; Guo, Z. & Lindberg, D.M.
Partner: UNT Libraries Government Documents Department
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PILOT PLANT SHUTDOWN AND Pu-Al PROCESSING

Description: The large aqueous pilot plant facilities at ORNL were cleaned and are being put in standby condition. Experience was gained during the year as anion exchange was used to recover more than one kg of plutonium left in the exploded evaporator system. This experience is being applied to a new recovery program just beginning in cell 1 of Building 4507. (auth)
Date: September 25, 1961
Creator: Bresee, J.C.
Partner: UNT Libraries Government Documents Department
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Aerial gamma ray and magnetic survey: Mississippi and Florida airborne survey, Nashville quadrangle, Tennessee, and Kentucky. Final report

Description: The Nashville quadrangle covers a portion of the interior lowland plateau region of the Midwestern Physiographic Province. The quadrangle contains a shallow to moderately thick Paleozoic section that overlies a Precambrian basement complex. Paleozoic carbonates dominate surficial exposures. A search of available literature revealed no known uranium deposits. Fifty-five uranium anomalies were detected and are discussed briefly. Most anomalies appear to relate to cultural features. Some have relatively high uranium concentration levels that may be significant despite their correlation with culture. Magnetic data appear to illustrate complexities in the Precambrian basement.
Date: September 1, 1980
Partner: UNT Libraries Government Documents Department
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Approach to decision modeling for an ignition test reactor

Description: A comparison matrix decision model is applied to candidates for a D-T ignition tokamak (TNS), including assessment of semi-quantifiable or judgemental factors as well as quantitative ones. The results show that TNS is mission-sensitive with a choice implied between near-term achievability and reactor technology.
Date: September 30, 1977
Creator: Howland, H.R. & Varljen, T.C.
Partner: UNT Libraries Government Documents Department
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Configuration Management Program Plan

Description: Westinghouse Savannah River Company (WSRC) has established a configuration management (CM) plan to execute the SRS CM Policy and the requirements of the DOE Order 4700.1. The Reactor Restart Division (RRD) has developed its CM Plan under the SRS CM Program and is implementing it via the RRD CM Program Plan and the Integrated Action Plan. The purpose of the RRD CM program is to improve those processes which are essential to the safe and efficient operation of SRS production reactors. This document provides details of this plan.
Date: September 25, 1991
Partner: UNT Libraries Government Documents Department
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Use of molybdenum ion source electrodes at RTNS-II

Description: Reports are reported for an ongoing effort to optimize D+ beam production by the MATS-III ion source used at RTNS-II. The three seven-aperture electrodes, originally consisting of water-cooled copper, have now been tested using uncooled molybdenum and with water cooling on the second (decel) electrode only. Details of the change, the results of the testing, and the benefits in operation, performance and cost are given.
Date: September 29, 1986
Creator: Massoletti, D.J.; Harter, G.A. & Heikkinen, D.W.
Partner: UNT Libraries Government Documents Department
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Structure functions: Their status and implications

Description: I discuss the current status of structure functions. Attention is given to the uncertainties in them and the implications of these uncertainties for experimental predictions. I indicate which experiments are capable of removing these uncertainties. 17 refs., 17 figs., 1 tab.
Date: September 29, 1988
Creator: Hinchliffe, I.
Partner: UNT Libraries Government Documents Department
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