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Variable-emittance filter for the Electron Laser Facility

Description: We describe a variable-emittance filter designed for the Electron Laser Facility (ELF). The filter attenuates the 4.5-MeV, 6-kA Experimental Test Accelerator (ETA) beam, permitting electrons only which fall within a given region of phase space (r, dr/dz) to pass. Initial experimental results are presented.
Date: August 1, 1983
Creator: Paul, A.C.; Sessler, A.M.; Wurtele, J.S.; Caporaso, G.J. & Cole, A.G.
Partner: UNT Libraries Government Documents Department

Fission product plateout and liftoff in the MHTGR primary system: A review

Description: A review is presented of the technical basis for predicting radioactivity release resulting from depressurization of an MHTGR primary system. Consideration is restricted to so called dry events with no involvement of the steam system. The various types of deposition mechanisms effective for iodine, cesium, strontium, and silver are discussed in terms of their chemical characteristics and the nature of the materials in the primary system. Emphasis is given to iodine behavior, including means for estimating the quantity available for release, the types of plateout locations in the primary system, and the effect of dust on distribution and release. The behavior of fission products cesium, strontium, and silver in such accidents is presented qualitatively. A major part of the review deals with expected dust levels, types, and transport. Available information on the level and nature of dust in the HTGR primary system is reviewed. A summary is presented of dust deposition and liftoff mechanisms. It was concluded that recent approaches to dust liftoff modeling, based on turbulent burst concepts for removal from surfaces, probably offer advantages over the current shear ratio approach. This study concludes that iodine releases from dry depressurization events are likely to be extremely low, on the order of millicuries, due to a predictably low degree of chemical desorption, a low degree of dust liftoff, and a low involvement of iodine with dust. It was also concluded that deposition mechanisms controlling the distribution of fission product material in the primary system, and hence also controlling the degree of liftoff, depend strongly on the chemical nature of the individual elements. Therefore contrary to the current practice, both plateout and liftoff models should reflect those unique chemical and physical properties. 56 refs., 16 figs., 23 tabs.
Date: April 1, 1991
Creator: Wichner, R.P. (Oak Ridge National Lab., TN (USA))
Partner: UNT Libraries Government Documents Department

Incremental cost analysis of advanced concept CAES systems

Description: The costs of compressed air energy storage (CAES) systems using thermal energy storage (TES) are compared to the costs of CAES systems without TES and simple cycle gas turbine systems. Comparisons are made in terms of the system energy costs levelized over the operating life of the systems. These are in 1985 price levels which is the assumed first year of operation for the systems.
Date: September 1, 1979
Creator: Knutsen, C.A.
Partner: UNT Libraries Government Documents Department

Emerging materials systems for solar cell applications - Cu/sub 2-x/Se. First quarterly technical progress report, May 1, 1979-August 1, 1979

Description: The purpose of this program is to investigate the feasibility of using Cu/sub 2-x/Se as a semiconductor material for the low cost production of photovoltaic solar cells. The first quarter of the program (May 1, 1979 through August 1, 1979) is described. The emphasis to date has been to produce Cu/sub 2-x/Se films of good uniformity and reproducibility. The films are deposited onto glass substrates heated to approximately 200/sup 0/C. The Cu and Se are evaporated from separate sources, each individually monitored for rate by quartz crystal microbalances. The techniques used are readily adaptable for scale up to large volume production. Preliminary measurements of optical absorption, electron diffraction, and Hall measurements have been made.
Date: August 1, 1979
Creator: Mickelsen, R.A.; Stewart, J.M.; Chen, W.S. & Buldhaupt, L.F.
Partner: UNT Libraries Government Documents Department

Thermal-structural response of EBR-II major components under reactor operational transients

Description: Until recently, the LMFBR safety research has been focused primarily on severe but highly unlikely accident, such as hypothetical-core-disruptive accidents (HCDA's), and not enough attention has been given to accident prevention, which is less severe but more likely sequence. The objective of the EBR-II operational reliability testing (ORT) is to demonstrate that the reactor can be designed and operated to prevent accident. A series of mild duty cycles and overpower transients were designed for accident prevention tests. An assessment of the EBR-II major plant components has been performed to assure structural integrity of the reactor plant for the ORT program. In this paper, the thermal-structural response and structural evaluation of the reactor vessel, the reactor-vessel cover, the intermediate heat exchanger (IHX) and the superheater are presented.
Date: January 1, 1983
Creator: Chang, L.K. & Lee, M.J.
Partner: UNT Libraries Government Documents Department

Neutral beam energy and power requirements for expanding radius and full bore startup of tokamak reactors

Description: Natural beam power and energy requirements are compared for full density full bore and expanding radius startup scenarios in an elongated plasma, The Next Step (TNS), as a function of beam pulse time and plasma density. Because of the similarity of parameters, the results should also be applicable to Engineering Test Facility (ETF) and International Tokamak Reactor (INTOR) studies. A transport model consisting of neoclassical ion conduction and anomalous electron conduction and diffusion based on ALCATOR scaling leads to average densities in the range <n> approx. 0.8 to 1.2 x 10/sup 14/ cm/sup -3/ being sufficient for ignition. Neutral deuterium beam energies in the range 120 to 180 keV are adequate for penetration, with the required power injected into the plasma decreasing with increasing beam energy. The neutral beam power decreases strongly with increasing beam pulse length b/sub b/ until t/sub b/ exceeds a few total energy confinement times, yielding b/sub b/ approx. = 4 to 6 s for the TNS plasma.
Date: September 1, 1979
Creator: Houlberg, W.A.; Mense, A.T. & Attenberger, S.E.
Partner: UNT Libraries Government Documents Department

Posttest analysis of LOFT LOCE L2-3 using the ESA RELAP4 blowdown model. [PWR]

Description: A posttest analysis of the blowdown portion of Loss-of-Coolant Experiment (LOCE) L2-3, which was conducted in the Loss-of-Fluid Test (LOFT) facility, was performed using the experiment safety analysis (ESA) RELAP4/MOD5 computer model. Measured experimental parameters were compared with the calculations in order to assess the conservatisms in the ESA RELAP4/MOD5 model.
Date: January 1, 1979
Creator: Perryman, J.L.; Samuels, T.K. & Cooper, C.H.
Partner: UNT Libraries Government Documents Department

Model of leaf photosynthesis and the effects of simple gaseous sulfur compounds (H/sub 2/S and SO/sub 2/)

Description: A theoretical development is presented of a leaf model and the effects of simple sulfur compounds (H{sub 2}S and SO{sub 2}) on photosynthesis based upon biochemical mechanisms. The model is developed to interpret short-term fumigation experiments and to use with season-long fumigation experiments to assess the effects of these compounds on growth. The model is designed as a submodel in a growth-and-allocation model of the plant. Included in this development are an analysis of the diffusion of CO{sub 2} and sulfur compound into the leaf, enzymatic interactions of sulfur in dark and light reactions of photosynthesis, temperature dependence of the kinetics and denaturization of enzymes, metabolism of sulfur compounds, and a hypothesis for the long-term effects of sulfur compounds. Enhanced photosynthesis at low H{sub 2}S levels, depression of photosynthesis at high H/sub 2/S levels, threshold to effects of sulfur pollutants, and the nature of the temperature dependence of photosynthesis are explained. Parameters in the model for sugar beets from data in the literature and from experiments funded through LLL were used. The properties of the model were analyzed. Data and experiments still required, sensitivities of the model to parameters and variables, implications to assessments, and the setting of standards for gaseous pollutants, are discussed.
Date: August 10, 1978
Creator: Kercher, J.R.
Partner: UNT Libraries Government Documents Department

Instrument calibration program for startup on FFTF

Description: Calibration of plant instruments and control equipment is a key plant startup activity. Clearly defined calibration requirements are needed to effectively guide this activity. A master-loop/sub-loop concept developed for use at the FFTF to help solve this problem is described. Startup testing methods related to the calibration activity are also described and critiqued.
Date: June 1, 1979
Creator: Swanson, C. D.
Partner: UNT Libraries Government Documents Department

MHD analysis of high (. beta. /sub t/) disruptions in PBX (Princeton Beta Experiment)

Description: PBX discharges run at the lowest q and highest (..beta../sub t/) always terminated in a hard disruption. The discharges, with (..beta../sub t/) values of up to 5.5% and q-values down to 2.2, were obtained by employing large current ramps and large gas feed rates during neutral beam injection. Previous work has indicated that the achieved (..beta../sub t/)-values were consistent with the limit imposed by the n = 1 ideal external kink with a conducting wall at b/a = 2. In this work, we investigate further the validity of ideal MHD theory in explaining the low-q/sub psi/j disruptions. In particular, the character of the pre-disruption MHD activity in these low-q discharges, specifically the time scales of growth and internal and external mode structures, was compared with those determined from theoretical calculations. The results of these comparisons indicate that non-ideal effects must be considered to obtain detailed agreement between theory and experiment. 13 refs., 6 figs.
Date: October 1, 1987
Creator: Jahns, G.L.; Chance, M.S.; Kaye, S.M.; Manickam, J.; Takahashi, H.; LeBlanc, B. et al.
Partner: UNT Libraries Government Documents Department

Monte Carlo simulations of fermion systems: the determinant method

Description: Described are the details for performing Monte Carlo simulations on systems of fermions at finite temperatures by use of a technique called the Determinant Method. This method is based on a functional integral formulation of the fermion problem (Blankenbecler et al., Phys. Rev D 24, 2278 (1981)) in which the quartic fermion-fermion interactions that exist for certain models are transformed into bilinear ones by the introduction (J. Hirsch, Phys. Rev. B 28, 4059 (1983)) of Ising-like variables and an additional finite dimension. It is on the transformed problem the Monte Carlo simulations are performed. A brief summary of research on two such model problems, the spinless fermion lattice gas and the Anderson impurity problem, is also given.
Date: January 1, 1985
Creator: Gubernatis, J.E.
Partner: UNT Libraries Government Documents Department

Intrinsic factors that can affect sensitivity to chromosome-aberration induction

Description: The paper addresses the question, are there individuals who are hypersensitive, or are more likely to be hypersensitive, to the induction of chromosome aberrations by radiation and chemicals. Lymphocytes of persons heterozygous for xeroderma pigmentosum, ataxia telangiectasia, and Fauconi's anemia were subjected to chemical and/or ionizing radiations to determine their sensitivity to chromosome aberration induction. In the majority of cases the sensitivity was intermediate between that of normal individuals and homozygotes for these genes. (ACR)
Date: January 1, 1982
Creator: Preston, R.J.
Partner: UNT Libraries Government Documents Department

Numerics for the simulation of electromagnetic-field propagation in nonionized and plasma media

Description: The numerical techniques used to simulate the propagation of low-frequency electromagnetic disturbances in Ohmic media and in collisional and collisionless plasmas are discussed. The scheme is based upon a multimedia propagation equation that is derived from Maxwell's equations. 10 refs., 5 figs.
Date: March 1, 1986
Creator: Borovsky, J.E.
Partner: UNT Libraries Government Documents Department

Production bias: A proposed modification of the driving force for void swelling under cascade damage conditions

Description: A new concept of point-defect production as the main driving force for void swelling under cascade damage conditions is proposed. This concept takes into account the recombination and formation of immobile clusters and loops of vacancies and interstitials in the cascade region. The life times of the clusters and loops due to desolution are strong functions of the temperature, as well as their vacancy and interstitial nature. The resulting biased production of free point defects from the internal sources is shown to be a strong driving force for void swelling. The characteristics of void swelling due to production bias are described and compared with experimental results. We conclude that the production bias concept provides a good description of void swelling under cascade damage conditions.
Date: November 1, 1991
Creator: Woo, C.H. (Atomic Energy of Canada Ltd., Pinawa, MB (Canada). Whiteshell Labs.); Singh, B.N. (Risoe National Lab., Roskilde (Denmark)) & Garner, F.A. (Pacific Northwest Lab., Richland, WA (United States))
Partner: UNT Libraries Government Documents Department

Rayleigh-Taylor instability and resulting failure modes of ablatively imploded inertial-fusion targets

Description: This article presents a theory of these instabilities and potential modes of failure caused by them. Discussions are given for the following: small amplitude growth of the outside surface instability; and modes of failure resulting from nonlinear development of the inside surface instability.
Date: April 15, 1983
Creator: Montierth, L. & Morse, R.
Partner: UNT Libraries Government Documents Department

TFTR Mirnov coil analysis at plasma start-up

Description: The methods for finding poloidal and toroidal numbers of MHD oscillations from Mirnov coils are reviewed and modified. Examples of various MHD phenomena occurring during start-up on TFTR are illustrated. It is found that the MHD mode structure best fits a model with the toroidal correction included. A new algorithm which finds m,n numbers can accommodate toroidal effects which are manifested in the phase data. The algorithm can find m,n numbers with a given toroidal correction parameter lambda', (lambda' = 0 cylindrical). This algorithm is also used to find the optimal value of lambda' automatically, eliminating the need for ''guesswork.'' The algorithm finds the best parameters to the fit much faster than more conventional computational techniques. 9 refs., 21 figs., 2 tabs.
Date: January 1, 1986
Creator: Harley, T.R.; Buchenauer, D.A.; Coonrod, J. & McGuire, K.M.
Partner: UNT Libraries Government Documents Department

Ceramic process and plant design for high-level nuclear waste immobilization

Description: In the last 3 years, significant advances in ceramic technology for high-level nuclear waste solidification have been made. Product quality in terms of leach-resistance, compositional uniformity, structural integrity, and thermal stability promises to be superior to borosilicate glass. This paper addresses the process effectiveness and preliminary designs for glass and ceramic immobilization plants. The reference two-step ceramic process utilizes fluid-bed calcination (FBC) and hot isostatic press (HIP) consolidation. Full-scale demonstration of these well-developed processing steps has been established at DOE and/or commercial facilities for processing radioactive materials. Based on Savannah River-type waste, our model predicts that the capital and operating cost for the solidification of high-level nuclear waste is about the same for the ceramic and glass options. However, when repository costs are included, the ceramic option potentially offers significantly better economics due to its high waste loading and volume reduction. Volume reduction impacts several figures of merit in addition to cost such as system logistics, storage, transportation, and risk. The study concludes that the ceramic product/process has many potential advantages, and rapid deployment of the technology could be realized due to full-scale demonstrations of FBC and HIP technology in radioactive environments. Based on our finding and those of others, the ceramic innovation not only offers a viable backup to the glass reference process but promises to be a viable future option for new high-level nuclear waste management opportunities.
Date: January 1, 1983
Creator: Grantham, L.F.; McKisson, R.L.; De Wames, R.E.; Guon, J.; Flintoff, J.F. & McKenzie, D.E.
Partner: UNT Libraries Government Documents Department

Radiological safety design considerations for fusion research experiments

Description: A wide variety of fusion research experiments are in the planning or construction stages. Two such experiments, the Nova Laser Fusion Facility and the Mirror Fusion Test Facility (MFTF), are currently under construction at Lawrence Livermore Laboratory. Although the plasma chamber vault for MFTF and the Nova target room will have thick concrete walls and roofs, the radiation safety problems are made complex by the numerous requirements for shield wall penetrations. This paper addresses radiation safety considerations for the MFTF and Nova experiments, and the need for integrated safety considerations and safety technology development during the planning stages of fusion experiments.
Date: January 1, 1979
Creator: Crase, K.W. & Singh, M.S.
Partner: UNT Libraries Government Documents Department

Cesium Chloride Compatibility Testing Program. Annual report, fiscal year 1984

Description: During the course of a prior examination, it was found that one of the aged test capsules exhibited discoloration and pitting on the outer surface of the inner capsule. The damage was attributed to problems encountered in the electropolishing operation, which is used to decontaminate the inner capsule after it is loaded with the CsCl and welded shut. A study was carried out in FY 1984 to: determine if the pitting was associated with the electropolishing operation; identify acceptable solution(s) to the problem; and establish the effect, if any, on the long-term integrity of the capsule. Another special study performed in FY 1984 was that of examining two capsules from the Waste Encapsulation and Storage Facility (WESF) storage pool. The objective was to establish the extent of the capsule corrosion while in storage. The study of cause and long-term consequences of the pitting on the WESF cesium chloride capsules has found: The pitting is caused by a nonuniform current distribution at the rack/capsule contact, which forms localized hot spots. The high temperature causes the acid to become more concentrated through boiling of the acid. The concentrated boiling phosphoric acid causes a high rate of corrosion which forms the crevice. The lack of intergranular attack at the base of the crevices and the favorable results of the mechanical testing leads to the conclusion that there will be no long-term failure mechanism accentuated by the pitting, beyond that of having a small hole in the capsule wall with a consequential thinner wall. An attempt to penetrate the capsule wall by electropolishing failed after 30 min with the loss of electrical contact. Consequently, the maximum wall penetration is 40 mils, out of a total thickness of 136 mil. No justification was found to require examination and repack of the existing capsules. A modification ...
Date: January 1, 1985
Creator: Bryan, G.H. & Divine, J.R.
Partner: UNT Libraries Government Documents Department

Evaluation of polarized fuels in a commercial deuterium/tritium tokamak reactor

Description: The use of polarized fuels in commercial deuterium-tritium tokamak fusion reactors has been assessed. Some of the advantages cited for this fueling modification have been evaluated. Although the advantages are real, their magnitude is such that polarized fuels do not appear to be a significant reactor in increasing the attractiveness of commercial reactor designs. 17 figs., 19 tabs.
Date: December 1, 1985
Creator: Finn, P.A.; Brooks, J.N.; Ehst, D.A.; Gohar, Y.; Mattas, R.F. & Baker, C.C.
Partner: UNT Libraries Government Documents Department

Preliminary assessment of costs and risks of transporting spent fuel by barge

Description: The purpose of this study is to analyze the costs and risks associated with transporting spent fuel by barge. The barge movements would be made in combination with rail movements to transport spent fuel from plants to a repository. For the purpose of this analysis, three candidate repository sites are analyzed: Yucca Mountain, Nevada, Deaf Smith, Texas, and Hanford, Washington. This report complements a report prepared by Sandia National Laboratories in 1984 that analyzes the costs and risks of transporting spent fuel by rail and by truck to nine candidate repository sites.
Date: December 1, 1985
Creator: Tobin, R.L.; Meshkov, N.K. & Jones, R.H.
Partner: UNT Libraries Government Documents Department

Fossil Energy Program. Progress report for October 1979

Description: This report, the sixty-third of a series, is a compendium of monthly progress reports for the ORNL research and development programs that are in support of the increased utilization of coal and other fossil fuel alternatives to oil and gas as sources of clean energy. The projects reported this month include those for coal conversion development, materials engineering, a coal equipment test program, an atmospheric fluid bed combustor for cogeneration, engineering studies and technical support, process and program analysis, environmental assessment studies, magnetic beneficiation of dry pulverized coal, technical support to the TVA fluid bed combustion program, coal cogeneration/district heating plant assessment, chemical research and development, and technical support to major liquefaction projects.
Date: December 1, 1979
Creator: McNeese, L.E.
Partner: UNT Libraries Government Documents Department

Results of the radiological survey at 88 East Central Avenue, Maywood, New Jersey (MJ037)

Description: Maywood Chemical Works (MCW) of Maywood, New Jersey, generated process wastes and residues associated with the production and refining of thorium and thorium compounds from monazite ores from 1916 to 1956. MCW supplied rare earth metals and thorium compounds to the Atomic Energy Commission and various other government agencies from the late 1940s to the mid-1950s. Area residents used the sandlike waste from this thorium extraction process mixed with tea and cocoa leaves as mulch in their yards. Some of these contaminated wastes were also eroded from the site into Lodi Brook. At the request of the US Department of Energy (DOE), a group from Oak Ridge National Laboratory conducts investigative radiological surveys of properties in the vicinity of MCW to determine whether a property is contaminated with radioactive residues, principally /sup 232/Th, derived from the MCW site. The survey typically includes direct measurement of gamma radiation levels and soil sampling for radionuclide analyses. The survey of this site, 88 East Central Avenue Maywood, New Jersey (MJ037), was conducted during 1988. Results of the survey indicated radioactivity in the range of normal background for the northern New Jersey area. Radiological assessments of soil samples from the site demonstrate no radionuclide concentrations in excess of DOE Formerly Utilized Sites Remedial Action Program criteria. 4 refs., 2 figs., 3 tabs.
Date: June 1, 1989
Creator: Foley, R.D. & Crutcher, J.W.
Partner: UNT Libraries Government Documents Department