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Cause of pitting in beryllium

Description: Light microscopy, bare-film radiography, secondary ion mass spectroscopy, electron microprobe and physical testing were used to examine beryllium specimens exhibiting a stratified, pitted, pattern after chemical milling. The objective was to find the cause of this pattern. Specimens were found to have voids in excess of density specification allowances. These voids are attributed, at least in part, to the sublimation of beryllium fluoride during the vacuum hot pressing operation. The origin of … more
Date: April 16, 1982
Creator: Kershaw, R. P.
Partner: UNT Libraries Government Documents Department
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Light Absorption and Scattering Mechanisms in Laser Fusion Plasmas

Description: The picture of laser light absorption and scattering which is emerging from theory and computer simulation studies of laser-plasma interactions is described. On the subject of absorption, we discuss theoretical and experimental evidence that resonance absorption in a steepened density profile is a dominant absorption mechanism. Recent work also indicates the presence of critical surface ripples, which we study using two and three dimensional computer simulations. Predictions of hot electron spe… more
Date: October 4, 1977
Creator: Barnes, C.; Estabrook, K. G.; Kruer, W. L.; Langdon, A. B.; Lasinski, B. F.; Max, C. E. et al.
Partner: UNT Libraries Government Documents Department
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Characterization of low-level waste from the industrial sector, and near-term projection of waste volumes and types

Description: A telephone survey of low-level waste generators has been carried out in order to make useful estimates of the volume and nature of the waste which the generators will be shipping for disposal when the compacts and states begin operating new disposal facilities. Emphasis of the survey was on the industrial sector, since there has been little information available on characteristics of industrial LLW. Ten large industrial generators shipping to Richland, ten shipping to Barnwell, and two whose w… more
Date: January 1, 1988
Creator: MacKenzie, D.R.
Partner: UNT Libraries Government Documents Department
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Measurements of the dependence of damage thresholds on laser wavelength, pulse duration and film thickness

Description: Results of three experiments will be described. We used 351-nm and 355-nm pulses with durations of 0.6, 1, 5 and 9 ns measure thresholds for a variety of anti-reflectance and high reflectance coatings. The functional form t/sup m/, with t the pulse duration, was used to scale fluence thresholds measured at 0.6 ns to those measured at 9.0 ns. Values of the coefficient m ranged from 0.10 to 0.51. The average value was 0.30. In the second experiment, we measured thresholds at 1064 nm, 527 nm and 3… more
Date: March 1, 1984
Creator: Rainer, F.; Vercimak, C.L.; Milam, D.; Carniglia, C.K. & Tuttle Hart, T.
Partner: UNT Libraries Government Documents Department
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Irradiation experiment for lithium ceramics

Description: Solid breeder materials are required in D-T fusion reactor blankets to convert fusion neutrons to tritium and thermal energy while providing some neutron shielding for the magnets. Lithium compounds such as Li/sub 2/O, LiAlO/sub 2/, Li/sub 4/SiO/sub 4/ and Li/sub 2/ZrO/sub 3/ have been proposed as solid breeder materials. Tritium is necessary to maintain the fuel supply for the D-T fusion reaction. No high burnup irradiation performance data is available for these materials in a neutron environ… more
Date: March 1, 1982
Creator: Hollenberg, G.W.
Partner: UNT Libraries Government Documents Department
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Conductor qualification tests for the 30-MJ Bonneville Power Administration SMES coil

Description: The 30-MJ energy storage coil for the Bonneville Power Administration requires a low-loss, cryostable conductor that is able to carry 4.9 kA in a field of 2.8 T and will maintain its properties over 10/sup 8/ partial discharge cycles. The multi-level cable which satisfies these requirements has been extensively tested at various stages in its development and in its final form. Tests have been performed to determine the effect of manufacturing options on ac losses, low temperature electrical res… more
Date: January 1, 1980
Creator: Schermer, R. I.; Boenig, H. J.; Henke, M.; Turner, R. D. & Schramm, R.
Partner: UNT Libraries Government Documents Department
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A benchmark-problem specification and calculation using SENSIBL, a one- and two-dimensional sensitivity and uncertainty analysis code of the AARE system

Description: The lack of suitable benchmark problems makes it difficult to test sensitivity codes with a covariance library. A benchmark problem has therefore been defined for one- and two-dimensional sensitivity and uncertainity analysis codes and code systems. The problem, representative of a fusion reactor blanket, has a simple, three-zone )tau)-z geometry containing a D-T fusion neutron source distributed in a central void region surrounded by a thick /sup 6/LiH annulus. The response of interest is the … more
Date: January 1, 1988
Creator: Muir, D. W.; Davidson, J. W.; Dudziak, D. J.; Davierwalla, D. M.; Higgs, C. E. & Stepanek, J.
Partner: UNT Libraries Government Documents Department
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Recovery of plutonium and americium from chloride salt wastes by solvent extraction

Description: Plutonium and americium can be recovered from aqueous waste solutions containing a mixture of HCl and chloride salt wastes by the coupling of two solvent extraction systems: tributyl phosphate (TBP) in tetrachloroethylene (TCE) and octyl(phenyl)-N,N-diisobutylcarbamoylmethylphosphine oxide (CMPO) in TCE. In the flowsheet developed, the salt wastes are dissolved in HCl, the Pu(III) is oxidized to the IV state with NaClO/sub 2/ and recovered in the TBP-TCE cycle, and the Am is then removed from t… more
Date: January 1, 1987
Creator: Reichley-Yinger, L. & Vandegrift, G.F.
Partner: UNT Libraries Government Documents Department
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Data analysis and management for the Uranium Resource Evaluation Project

Description: The Department of Energy has funded a large data collection effort with the purpose of determining the US uranium resources. This Uranium Resource Evaluation (URE) Project required a large data management effort which involved collection, retrieval, processing, display, and analysis of large volumes of data. Many of the characteristics of this data processing system are relevant to other applications, particularly where routine processing involves analyses for input into numerous technical repo… more
Date: January 1, 1980
Creator: Kane, V.E.
Partner: UNT Libraries Government Documents Department
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Source-jerk analysis using a semi-explicit inverse kinetic technique

Description: A method is proposed for measuring the effective reproduction factor, k, in subcritical systems. The method uses the transient response of a subcritical system to the sudden removal of an extraneous neutron source (i.e., a source jerk). The response is analyzed using an inverse kinetic technique that least-squares fits the exact analytical solution corresponding to a source-jerk transient as derived from the point-reactor model. It has been found that the technique can provide an accurate means… more
Date: January 1, 1985
Creator: Spriggs, G.D. & Pederson, R.A.
Partner: UNT Libraries Government Documents Department
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Estimates of SASE power in the short wavelength region

Description: Given a sufficiently bright electron beam, the self-amplified-spontaneous emission (SASE) can provide gigawatts of short wavelength coherent radiation. The advantages of SASE approach are that is requires neither optical cavity nor an imput seed laser. In this note, we estimate the peak power performance of SASE for wavelengths shorter than 1000 {Angstrom}. At each wavelength, we calculate the saturated power from a uniform parameter undulator and the enhanced power from a tapered undulator. Th… more
Date: March 1, 1992
Creator: Kim, Kwang-Je.
Partner: UNT Libraries Government Documents Department
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Operating experience and procedures at the tritium systems test assembly

Description: Operating procedures are important for the safe and efficient operation of the Tritium Systems Test Assembly (TSTA). TSTA has been operating for four years with tritium in a safe and efficient manner. The inventory of tritium in the process loop is 100 grams and several milestone runs have been completed. This paper describes the methods used to operate TSTA. 3 refs., 1 fig.
Date: January 1, 1988
Creator: Carlson, R.V.; Binning, K.E.; Cole, S. P.; Jenkins, E. M.; Wilhelm, R. C. & Cole, S. P.
Partner: UNT Libraries Government Documents Department
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Evidence of former higher temperatures from alteration minerals, Bostic 1-A well, Mountain Home, Idaho

Description: Cuttings from the silicic volcanics in the Bostic 1-A well near Mountain Home, Idaho have been examined petrographically with the assistance of x-ray diffraction and electron microprobe analyses. Results indicate that these rocks have been subjected to much higher temperatures than were observed in the well in 1974, when a static temperature log was run. It is not known to what extent the alternation may be due to greater depth of burial in the past, or whether it resulted from an early hydroth… more
Date: January 1, 1982
Creator: Arney, B.
Partner: UNT Libraries Government Documents Department
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Potential effects of maternal contribution on egg and larva population dynamics of striped bass: Integrated individual-based model and directed field sampling

Description: We have used a bioenergetically-driven, individual-based model (IBM) of striped bass as a framework for synthesizing available information on population biology and quantifying, in a relative sense, factors that potentially affect year class success. The IBM has been configured to simulate environmental conditions experienced by several striped bass populations; i.e., in the Potomac River, MD; in Hudson River, NY; in the Santee-Cooper River System, SC, and; in the San Joaquin-Sacramento River S… more
Date: January 1, 1991
Creator: Cowan, J.H., Jr. (Maryland Univ., Solomons, MD (United States). Chesapeake Biological Lab.) & Rose, K.A. (Oak Ridge National Lab., TN (United States))
Partner: UNT Libraries Government Documents Department
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Calculations of thermal-reactor spent-fuel nuclide inventories and comparisons with measurements

Description: Comparisons with integral measurements have demonstrated the accuracy of CINDER codes and libraries in calculating aggregate fission-product properties, including neutron absorption, decay power, and decay spectra. CINDER calculations have, alternatively, been used to supplement measured integral data describing fission-product decay power and decay spectra. Because of the incorporation of the extensive actinide library and the use of ENDF/B-V data, it is desirable to compare the inventory of i… more
Date: January 1, 1982
Creator: Wilson, W. B.; LaBauve, R. J. & England, T. R.
Partner: UNT Libraries Government Documents Department
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Adaptive Mesh Refinement for 1-Dimensional Gas Dynamics

Description: We consider the solution of the one-dimensional equation of gas-dynamics. Accurate numerical solutions are difficult to obtain on a given spatial mesh because of the existence of physical regions where components of the exact solution are either discontinuous or have large gradient changes. Numerical methods treat these phenomena in a variety of ways. In this paper, the method of adaptive mesh refinement is used. A thorough description of this method for general hyperbolic systems is given else… more
Date: 1982-08~
Creator: Hedstrom, Gerald; Rodrigue, Garry; Berger, Marsha & Oliger, Joseph
Partner: UNT Libraries Government Documents Department
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Magma energy and geothermal permeability enhancement programs

Description: Accomplishments during FY85 and project plans for FY86 are described for the Magma Energy Extraction and Permeability Enhancement programs. (ACR)
Date: January 1, 1985
Creator: Dunn, J.C.
Partner: UNT Libraries Government Documents Department
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Plutonium scrap recovery at Savannah River: Past, present, and vision of the future

Description: As a result of the changing requirement, plus environmental and regulatory commitments, SRP now has essentially completed its paradigm shift. SRP has been transformed from primarily a reprocessor of irradiated uranium targets to primarily a reprocessor of non-specification plutonium. This is the mission which will carry SRP into the 21st Century. Accomplishment of the defined goals for the three-pronged RandD program will achieve several objectives: exploit new processes for recovering low-grad… more
Date: January 1, 1988
Creator: Gray, Leonard W.; Gray, John H.; Blancett, Allen L.; Lower, William M. & Rudisill, Tracy S.
Partner: UNT Libraries Government Documents Department
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Aspects of model selection in multivariate analyses

Description: Analysis of data sets that involve large numbers of variables usually entails some type of model fitting and data reduction. In regression problems, a fitted model that is obtained by a selection process can be difficult to evaluate because of optimism induced by the choice mechanism. Problems in areas such as discriminant analysis, calibration, and the like often lead to similar difficulties. The preceeding sections reviewed some of the general ideas behind assessment of regression-type predic… more
Date: January 1, 1982
Creator: Picard, R.
Partner: UNT Libraries Government Documents Department
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Current drive and heating systems based on high-energy (1- to 3-MeV) negative ion beams

Description: This paper describes a concept for a current drive system based on negative ions with beam energy > 1 MeV. Preliminary physics calculations show that the core current necessary for stability enhancement can best be achieved by beams with energy ranging from 1 to 4 MeV. Further study and experiments will better define the optimum energy. Work under way at Oak Ridge National Laboratory (ORNL) and at collaborating institutes in Canada and the Federal Republic of Germany is defining a system, its e… more
Date: January 1, 1988
Creator: Becraft, W. R.; Akerman, M. A.; Haselton, H. H.; Murphy, B. D.; Lousteau, D. C.; Ryan, P. M. et al.
Partner: UNT Libraries Government Documents Department
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Some recent developments in nuclear charged particle detectors

Description: The latest developments of large-area, position sensitive gas-filled ionization chambers are described. Multi-wire-proportional chambers as position-sensing and parallel-plate-avalanche counters as time-sensing detectors at low pressure (5 torr) have proven to be useful and reliable instruments in heavy ion physics. Gas (proportional) scintillation counters, used mainly for x-ray spectroscopy, have recently been applied as particle detectors. Finally, a brief description of a large plastic scin… more
Date: August 1, 1980
Creator: Stelzer, H.
Partner: UNT Libraries Government Documents Department
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Pressure losses in fracture-dominated reservoirs: the wellbore constriction effect

Description: Improved energy production from many types of energy reservoirs such as hot dry rock geothermal as well as hydraulically fractured oil, gas, and other geothermal reservoirs requires a better understanding of the fluid mechanics in the vicinity of the fracture-wellbore intersection. Typically, the aperture (smallest dimension) of a hydraulic fracture is only of the order of 1 mm (0.04 in.) so that reasonable energy production rates from geothermal systems require fairly large flow velocities wit… more
Date: January 1, 1980
Creator: Murphy, H.
Partner: UNT Libraries Government Documents Department
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Measurement of energy loss in the region of relativistic rise for particle identification

Description: The following boundary conditions are desirable for particle detectors providing momentum and mass measurement in a magnetic field. A multilayer drift chamber of the socalled ''bicycle'' type with a radius of 1.5 m is considered. The useful track length will be l/sub min/ = 1.3 m for a straight track at 90/sup 0/ to the beam axis. Two examples for possible subdivisions of this volume are chosen: (1) number of layers, n = 200 and thickness/layer, x = 6.5 mm; and (2) n = 56 and x = 23 mm. An anal… more
Date: January 1, 1977
Creator: Fischer, J.; Okuno, H. & Walenta, A.H.
Partner: UNT Libraries Government Documents Department
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Advances in the Helium-Jet Coupled on-Line Mass Separator RAMA. [Recoil Atom Mass Analyzer]

Description: General improvements to the on-line mass separator RAMA (Recoil Atom Mass Analyzer) have yielded a greater reliability and efficiency for some elements. A new utilitarian helium-jet chamber has been installed to facilitate quick target and degrader foil changes in addition to a new ion source holder. A higher efficiency hollow-cathode, cathode-extraction ion source, for lower melting point elements (< 1200/sup 0/C) has also been designed. Tests with the beta-delayed proton emitter /sup 37/Ca… more
Date: January 1, 1980
Creator: Moltz, D. M.; Aysto, J.; Cable, M. D.; Parry, R. F.; Haustein, P. E.; Wouters, J. M. et al.
Partner: UNT Libraries Government Documents Department
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