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Amplification of a bi-phase shift-key modulated signal by a mm-wave FEL

Description: Bi-phase shift keying (BPSK) is a modulation scheme used in communications and radar in which the phase of a transmitted rf signal is switched in a coded pattern between discrete values differing by {pi} radians. The transmitted information rate (in communications) or resolution (in imaging radar) depends on the rate at which the transmitted signal can be modulated. Modulation rates of greater than 1 GHz are generally desired. Although the instantaneous gain bandwidth of a mm-wave FEL amplifier can be much greater than 10 GHz, slippage may limit the BPSK modulation rate that can be amplified. Qualitative slippage arguments would limit the modulation rate to relatively low values; nevertheless, simulations with a time-dependent FEL code (GINGER) indicate that rates of 2 GHz or more are amplified without much loss in modulation integrity. In this paper we describe the effects of slippage in the simulations and discuss the limits of simple arguments.
Date: October 1, 1991
Creator: Prosnitz, D.; Scharlemann, E.T. & Sheaffer, M.K.
Partner: UNT Libraries Government Documents Department
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Nuclear safety guide TID-7016 Revision 2

Description: The present revision of TID-7016 Nuclear Safety Guide is discussed. This Guide differs significantly from its predecessor in that the latter was intentionally conservative in its recommendations. Firmly based on experimental evidence of criticality, the original Guide and the first revision were considered to be of most value to organizations whose activities with fissionable materials were not extensive and, secondarily, that it would serve as a point of departure for members of established nuclear safety teams, experienced in the field. The reader will find a significant change in the character of information presented in this version. Nuclear Criticality Safety has matured in the past twelve years. The advance of calculational capability has permitted validated calculations to extend and substitute for experimental data. The broadened data base has enabled better interpolation, extension, and understanding of available, information, especially in areas previously addressed by undefined but adequate factors of safety. The content has been thereby enriched in qualitative guidance. The information inherently contains, and the user can recapture, the quantitative guidance characteristic of the former Guides by employing appropriate safety factors. In fact, it becomes incumbent on the Criticality Safety Specialist to necessarily impose safety factors consistent with the possible normal and abnormal credible contingencies of an operation as revealed by his evaluation. In its present form the Guide easily becomes a suitable module in any compendium or handbook tailored for internal use by organizations. It is hoped the Guide will continue to serve immediate needs and will encourage continuing and more comprehensive efforts toward organizing nuclear criticality safety information.
Date: January 1, 1980
Creator: Thomas, J T
Partner: UNT Libraries Government Documents Department
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Assessment of light water reactor fuel damage during a reactivity initiated accident

Description: This paper presents an assessment of LWR fuel damage during a reactivity initiated accident and comments on the adequacy of the present USNRC design requirements. Results from early SPERT tests are reviewed and compared with results from recent computer simulations and PBF tests. A progression of fuel rod and cladding damage events is presented. High strain rate deformation of relatively cool irradiated cladding early in the transient may result in fracture at a radial average peak fuel enthalpy of approximately 140 cal/g UO/sub 2/. Volume expansion of previously irradiated fuel upon melting may cause deformation and rupture of the cladding, and coolant channel blockage at higher peak enthalpies.
Date: January 1, 1980
Creator: MacDonald, P. E.; Seiffert, S. L.; Martinson, Z. R.; McCardell, R. K.; Owen, D. E. & Fukuda, S. K.
Partner: UNT Libraries Government Documents Department
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Recovery of deformed and hydrogen-charge palladium

Description: Positron lifetime and Doppler-broadening studies made at 300 K have been used to investigate the interaction between interstitial hydrogen and lattice defects in deformed Pd. Specimens were charged with hydrogen at 300 K to levels up to 0.1%. The presence of hydrogen was found to have no effect on the recovery curves of Pd upon annealing to 400/sup 0/C. By 400/sup 0/C the values for both lifetime and Doppler-broadening for both cold worked and cold worked plus hydrogen were below the values obtained for annealed pure Pd. This can be interpreted as gaseous-impurity-trapped vacancies being present after the 1200/sup 0/C anneal, but being swept away by the dislocation microstructure recovery between 200 to 400/sup 0/C.
Date: January 1, 1982
Creator: Snead, C. L. Jr.; Lynn, K. G. & Lynch, J. F.
Partner: UNT Libraries Government Documents Department
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INSPECT: a package of computer programs for planning and evaluating safeguards inspections

Description: As part of the US Program of Technical Assistance to IAEA Safeguards, PNL has developed a package of computer programs, called INSPECT, that can be used in planning and evaluating safeguards inspections of various types of nuclear facilities. The programs are based on the statistical methods described in Part F of the IAEA Safeguards Technical Manual and can be used to calculate the variance components of the MUF (Material Unaccounted For) statistic, the variance components of the D (difference) statistic, attribute and variables sampling plans, and a measure of the effectiveness of the inspection plan. The paper describes the programs, reviews a number of applications, and indicates areas for future work.
Date: January 1, 1980
Creator: Mullen, M.F.
Partner: UNT Libraries Government Documents Department
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A comparison of predicted and observed turbulent wind fields present in natural and internal wind park environments

Description: This paper assesses the accuracy of simulated wind fields for both the natural flow and that within a wind park environment. The simulated fields are compared with the observed ones in both the time and frequency domains. Actual measurements of the wind fields and the derived kinematic scaling parameters upwind and downwind of a large San Gorgonio Pass wind park are used. The deviations in the modeled wind field from the observed are discussed. 10 refs., 6 figs., 2 tabs.
Date: October 1, 1991
Creator: Kelly, N D & Wright, A D
Partner: UNT Libraries Government Documents Department
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Bag model, the hyperspherical formalism and the heavy baryons

Description: The bag model framework is used to discuss the heavy baryons, triple flavored objects like ccc, cbb, etc. A nonrelativistic picture seems justified. It is insisted that the long-range interaction consist of a genuine three-body force. Once the potential energy of the three quarks is determined, the three-body Schroedinger equation is solved by the method of hyperspherical expansion. 1 table. (RWR)
Date: January 1, 1980
Creator: Richard, J. M.
Partner: UNT Libraries Government Documents Department
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Experience base for Radioactive Waste Thermal Processing Systems: A preliminary survey

Description: In the process of considering thermal technologies for potential treatment of the Idaho National Engineering Laboratory mixed transuranic contaminated wastes, a preliminary survey of the experience base available from Radioactive Waste Thermal Processing Systems is reported. A list of known commercial radioactive waste facilities in the United States and some international thermal treatment facilities are provided. Survey focus is upon the US Department of Energy thermal treatment facilities. A brief facility description and a preliminary summary of facility status, and problems experienced is provided for a selected subset of the DOE facilities.
Date: April 1, 1992
Creator: Mayberry, J.; Geimer, R.; Gillins, R.; Steverson, E.M.; Dalton, D. (Science Applications International Corp., Idaho Falls, ID (United States)) & Anderson, G.L. (EG and G Idaho, Inc., Idaho Falls, ID (United States))
Partner: UNT Libraries Government Documents Department
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COMP: a BASIC language nonlinear least-squares curve fitting program

Description: COMP is an interactive nonlinear least squares routine written in BASIC language and used to obtain estimates of parameters in nonlinear functions and to approximate their associated statistical errors. The program uses the linearizing (or Taylor Series) expansion of partial derivatives outlined in Draper and Smith, (1966, pp. 267 to 270). Therefore, partial derivatives must be supplied (as well as the function) by the user for any new models not currently contained in the programs. When a linearizing method is used to estimate parameters in a nonlinear model, all the usual procedures of linear regression theory can be applied. However, the results so obtained are only valid insofar as the linearized form approximates the true model. All of the statistics computed by COMP should be viewed with this restriction in mind. The output of COMP includes the variance-covariance matrix, t-tests for parameters, Von Neumann's ratio, observed, predicted and residual values, the error mean square, and an optional procedure to evaluate heteroscedasticity.
Date: November 1, 1977
Creator: Thomas, J. M.; Cochran, M. I.; Watson, C. R. & Eberhardt, L. L.
Partner: UNT Libraries Government Documents Department
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Low-Cost Solar Array Project. Progress report 14, August 1979-December 1979 and proceedings of the 14th Project Integration Meeting

Description: Progress made by the Low-Cost Solar Array Project during the period August through November 1979, is described. Progress on project analysis and integration; technology development in silicon material, large-area sheet silicon, and encapsulation; production process and equipment development; engineering, and operations, and the steps taken to integrate these efforts are detailed. A report on the Project Integration Meeting held December 5-6, 1979, including copies of the visual materials used, is presented.
Date: January 1, 1980
Partner: UNT Libraries Government Documents Department
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Biliary Excretion of /Sup 99m/Tc Albumin Microaggregate Degradation Products (a Method for Measuring Kupffer Cell Digestive Function.).

Description: The rapid metabolism of radioactive albumin colloids used for liver-spleen-bone marrow scanning radiation exposure to these organs and permits one to study the proteolytic digestive capacity of the reticuloendothial system (RES)
Date: October 31, 1971
Creator: Kitani, K. & Taplin, G. V.
Partner: UNT Libraries Government Documents Department
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Economic foundations of permanent pioneer communities

Description: Although pioneer settlements are often founded for political or ideological reasons distinct from short-term economic justifications, their survival and growth depend on economic factors. The settlers must be able to make a living, whether at subsistence, commercial farming, fishing, mining, manufacturing, trade, or in government service. Although most of this discussion is highly speculative, it does seem from the historical material that there are plausible ways in which an evolutionary lunar program could lead, step by step, to settlement. Once a lunar facility has achieved basic self-sufficiencies in the production of oxygen, food, and construction materials, crew rotation would become a dominant cost factor in continuing lunar operations. At such a point, establishment of a resident staff begins to make economic sense. Subsequent encouragement of private-sector economic activities through such mechanisms as resident bonuses, local purchase preferences, and transfer of responsibility of basic services and production capabilities might well reduce operating costs and significantly multiply the economic effects of the basic import capacity provided by the facility's local expenditures.
Date: January 1, 1988
Creator: Jones, E.M.
Partner: UNT Libraries Government Documents Department
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INEX simulations of the optical performance of the AFEL

Description: The AFEL (Advanced Free-Electron Laser) Project at Los Alamos National Laboratory is presently under construction. The project's goal is to produce a very high-brightness electron beam which will be generated by a photocathode injector and a 20 MeV rf-linac. Initial laser experiments will be performed with a 1-cm-period permanent magnet wiggler which will generate intense optical radiation near a wavelength of 3.7 {mu}m. Future experiments will operate with slotted-tube'' electromagnetic wigglers (formerly called pulsed- wire'' wigglers). Experiments at both fundamental and higher-harmonic wavelengths are planned. This paper presents results of INEX (Integrated Numerical EXperiment) simulations of the optical performance of the AFEL. These simulations use the electron micropulse produced by the accelerator/beam transport code PARMELA in the 3-D FEL simulation code FELEX. 9 refs., 4 figs., 6 tabs.
Date: January 1, 1991
Creator: Goldstein, J.C.; Wang, T.S.F. & Sheffield, R.L.
Partner: UNT Libraries Government Documents Department
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Enhanced oil recovery by CO/sub 2/ foam flooding. Annual report, October 1, 1982-September 30, 1983

Description: The objective is to identify commercially available additives which are effective in reducing the mobility of carbon dioxide, CO/sub 2/, thereby improving its efficiency in the recovery of tertiary oil, and which are low enough in cost to be economically attractive. During the past year significant progress has been made in developing a commercial method of reducing the mobility of carbon dioxide in enhanced oil recovery processes. Four basic chemical structures, listed below, appear to show most promise for gas mobility control: (1) ethoxylated adducts of C/sub 8/ - C/sub 14/ linear alcohols; (2) sulfate esters of ethoxylated C/sub 9/ - C/sub 16/ linear alcohols; (3) low molecular weight co-polymers of ethylene oxide and propylene oxide; and (4) synthetic organic sulfonates. With the exception of the sulfonates, the above types are compatible with normal oil field brines, unaffected by the presence of crude oil and stable under conditions common in a petroleum reservoir. The second significant result during the year involves identification of several sulfonate structures that have high potential for mobility control for carbon dioxide. Commercial sulfonate additives are available that appear optimum for reservoirs where freshwater will be used to inject the surfactant solution. They can also be considered for limited brine applications, for as temperature increases the utility of sulfonates for mobility control also increases. This is encouraging since some of the previously identified additives are chemically unstable at temperatures encountered in most petroleum reservoirs. 113 references, 23 figures, 4 tables.
Date: December 22, 1983
Partner: UNT Libraries Government Documents Department
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DWPF waste glass Product Composition Control System

Description: The Defense Waste Processing Facility (DWPF) will be used to blend aqueous radwaste (PHA) with solid radwaste (Sludge) in a waste receipt vessel (the SRAT). The resulting SRAT material is transferred to the SME an there blended with ground glass (Frit) to produce a batch of melter feed slurry. The SME material is passed to a hold tank (the MFT) which is used to continuously feed the DWPF melter. The melter. The melter produces a molten glass wasteform which is poured into stainless steel canisters for cooling and, ultimately, shipment to and storage in a geologic repository. The Product Composition Control System (PCCS) is the system intended to ensure that the melt will be processible and that the glass wasteform will be acceptable. This document provides a description of this system.
Date: January 1, 1992
Creator: Brown, K.G. & Postles, R.L.
Partner: UNT Libraries Government Documents Department
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State-of-the-art for evaluating the potential impact of tectonism and volcanism on a radioactive waste repository

Description: Most estimates of the time required for safe isolation of radioactive wastes from the biosphere range from 100,000 to 1,000,000 years. For such long time spans, it is necessary to assess the potential effects of geologic processes such as volcanism and tectonic activity on the integrity of geologic repositories. Predictions of geologic phenomena can be based on probabilistic models, which assume a random distribution of events. The necessary historic and geologic records are rarely available to provide an adequate data base for such predictions. The observed distribution of volcanic and tectonic activity is not random, and appears to be controlled by extremely complex deterministic processes. The advent of global plate tectonic theory in the past two decades has been a giant step toward understanding these processes. At each potential repository site, volcanic and tectonic processes should be evaluated to provide the most thorough possible understanding of those deterministic processes. Based on this knowledge, judgements will have to be made as to whether or not the volcanic and tectonic processes pose unacceptable risk to the integrity of the repository. This report describes the potential hazards associated with volcanism and tectonism, and the means for evaluating these processes.
Date: July 16, 1980
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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Excitation of giant resonances via direct reactions

Description: Experimental measurements of electric giant multipole resonances are discussed. The parameters of the giant quadrupole resonance are now firmly established by an extensive set of measurements. The GQR is providing a significant influence in other areas of nuclear physics. The monopole resonance has now been established and its observation has provided the first direct measure of the nuclear compressibility. A strong case for the existence of a giant octupole resonance is now being made through a variety of hadron reactions. However, the supply of giant multipole resonances has not been exhausted. The newer techniques such as higher energy proton scattering, charge exchange reactions, heavy-ion scattering and pion reactions offer considerable hope for identifying new resonances during the next few years.
Date: January 1, 1982
Creator: Bertrand, F.E.
Partner: UNT Libraries Government Documents Department
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Note on the cryostatic stability of superconducting composites

Description: A careful discussion is given of the ''equal area condition'' developed by Maddock et al. In order to make the essential points as clear as possible, analytical solutions are derived under simplifying assumptions (simple model for heat transfer by nucleate and film boiling liquid helium; constant heat conduction and specific heat) instead of using more realistic but less controllable computer calculations. A quantitative definition of the concept of a long wire is given. Numerical examples for the Maddock transition characterized by the equal area condition are given for a long superconducting composite with linear cooling and for a liquid helium-cooled resistance wire of finite length. In addition, cases are shown where instead of applying the equal area stability condition, time-dependent solutions should be considered.
Date: February 1, 1978
Creator: Gauster, W. F.
Partner: UNT Libraries Government Documents Department
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Pion correlations as a function of atomic mass in heavy ion collisions

Description: The method of two pion interferometry was used to obtain source-size and lifetime parameters for the pions produced in heavy ion collisions. The systems used were 1.70 {center dot} A GeV {sup 56}Fe + Fe, 1.82 {center dot} A GeV {sup 40}Ar + KCl and 1.54 {center dot} A GeV {sup 93}Nb + Nb, allowing for a search for dependences on the atomic number. Two acceptances (centered, in the lab., at {approximately} 0{degrees} and 45{degrees}) were used for each system, allowing a search for dependences on the viewing angle. The correlation functions were calculated by comparing the data samples to background (or reference) samples made using the method of event mixing, where pions from different events are combined to produce a data sample in which the Bose-Einstein correlation effect is absent. The effect of the correlation function on the background samples is calculated, and a method for weighting the events to remove the residual correlation effect is presented. The effect of the spectrometer design on the measured correlation functions is discussed, as are methods for correcting for these effects during the data analysis. 58 refs., 39 figs., 18 tabs.
Date: November 26, 1989
Creator: Chacon, A.D.
Partner: UNT Libraries Government Documents Department
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The development of precipitated iron catalysts with improved stability

Description: The objective of this program is to identify the chemical principles governing the deactivation of precipitated iron catalysts during Fischer-Tropsch synthesis and to use these chemical principles in the design of catalysts suitable for slurry reactors. The performance targets are 88% CO+H{sub 2} conversion with less than 1% deactivation/day for 1 month and a methane and ethane selectivity of no more than 7% (based on hydrocarbons and oxygenates only) at a space velocity of at least 2 normal liters per hr per gram iron (NL/hr/gFe) using a synthesis gas with 0.5-1.0 H{sub 2}:CO ratio in a slurry reactor.
Date: May 6, 1992
Creator: Abrevaya, H.
Partner: UNT Libraries Government Documents Department
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The Federal Reporter. Volume 94 Cases Argued and Determined in the Circuit Courts of Appeals and Circuit and District Courts of the United States. June-August, 1899.

Description: The Federal Reporter contains the text of decisions and commentary regarding cases tried in circuit and district courts throughout the United States. The opinions printed in the volumes include both written statements and oral comments transcribed for publication. Index of cases starts on page vii.
Date: 1899
Partner: UNT Libraries Government Documents Department
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