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Operating experience and cesium recycling on the LASL polarized triton source
The polarized triton source has had over 3000 hours of operation. Experience gained with Lamb-shift operation that are not unique to tritium handling are discussed. (GHT)
Date:
January 1, 1980
Creator:
Hardekopf, R.A.
Object Type:
Article
System:
The UNT Digital Library
Rigid muffin-tin approximation for the electron-phonon interaction in transition metals
Progress in calculating the electron-phonon parameters of transition metals has been based on either the rigid muffin-tin approximation (RMTA) or the fitted modified tight-binding approximation (FMTBA). The RMTA has been shown to be remarkably accurate for average electron-phonon properties, but there are indications that RMTA matrix elements may be too small at low momentum transfer. An attempt is made to demonstrate these assertions concerning the accuracy of RMTA and the numerous electron-phonon calculations are placed in a broader perspective by a demonstration of how they can be used to explain the trends in the strength of the electron-phonon coupling among the transition metals and the A-15 compounds. (GHT)
Date:
January 1, 1980
Creator:
Butler, W. H.
Object Type:
Article
System:
The UNT Digital Library
Nuclear safety guide TID-7016 Revision 2
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 …
Date:
January 1, 1980
Creator:
Thomas, J T
Object Type:
Article
System:
The UNT Digital Library
Assessment of light water reactor fuel damage during a reactivity initiated accident
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.
Object Type:
Article
System:
The UNT Digital Library
Recovery of deformed and hydrogen-charge palladium
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.
Object Type:
Article
System:
The UNT Digital Library
INSPECT: a package of computer programs for planning and evaluating safeguards inspections
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.
Object Type:
Article
System:
The UNT Digital Library
Bag model, the hyperspherical formalism and the heavy baryons
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.
Object Type:
Article
System:
The UNT Digital Library
Low-Cost Solar Array Project. Progress report 14, August 1979-December 1979 and proceedings of the 14th Project Integration Meeting
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
Creator:
unknown
Object Type:
Report
System:
The UNT Digital Library
Excitation of giant resonances via direct reactions
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.
Object Type:
Article
System:
The UNT Digital Library
Picotron 100 streak tubes as a 150-channel photometer
The characterization of a streak camera based upon Picotron 100 tube types is given. Both a large (30 cm 1 x 10 cm dia.) and a small (18 cm 1 x 5 cm dia.) version of this design has been tested. Over 150 channels of information are simultaneously time resolved with system S.N.R. of 3 at 100 picosecond time resolution without post intensification. Absolute photometric evaluation is given in the dynamic mode, i.e. while operating in the picosecond time domain. Such quantitative data has been lacking in the past, particularly for multiple channel applications.
Date:
January 1, 1982
Creator:
Majumdar, S.; Weiss, P.B. & Black, J.P.
Object Type:
Article
System:
The UNT Digital Library
Low cost Czochralski crystal growing technology: near term implementation of the flat plate photovoltaic cost reduction of the Low Cost Solar Array Project. Fifth quarterly progress report, April 1-June 30, 1980
During this reporting period, the primary activity has been to develop microprocessor control of the crystal growth process and to develop and demonstrate the accelerated crystal growth program. Accelerated recharging of the quartz crucible by the RF melting of polycrystalline silicon feed rods was deemphasized by JPL primarily due to the unavailability of suitable quality feed rods at an effective economical price. The development of the cold crucible program as an alternative method of crucible recharging was continued, but at a lower priority. Work continued on the accelerated crystal growth program. Crystal growth runs were made utilizing the water cooled work coil previously used in the RF polycrystalline silicon rod melting program. Accelerated growth rates were demonstrated but an oxide build-up on the cold surface of the work coil, resulting in heavy flaking and consequent falling of oxide into the melt, resulted in abandoning this approach and redesigning, evaluating, and demonstrating an alternative heat sink arrangement. All necessary parts were received for the cold crucible premelter and system was assembled and interfaced to the multiturn high voltage RF power supply.
Date:
January 1, 1980
Creator:
Roberts, E. G.
Object Type:
Report
System:
The UNT Digital Library
Impulsive ion acceleration in earth's outer magnetosphere
Considerable observational evidence is found that ions are accelerated to high energies in the outer magnetosphere during geomagnetic disturbances. The acceleration often appears to be quite impulsive causing temporally brief (10's of seconds), very intense bursts of ions in the distant plasma sheet as well as in the near-tail region. These ion bursts extend in energy from 10's of keV to over 1 MeV and are closely associated with substorm expansive phase onsets. Although the very energetic ions are not of dominant importance for magnetotail plasma dynamics, they serve as an important tracer population. Their absolute intensity and brief temporal appearance bespeaks a strong and rapid acceleration process in the near-tail, very probably involving large induced electric fields substantially greater than those associated with cross-tail potential drops. Subsequent to their impulsive acceleration, these ions are injected into the outer trapping regions forming ion ''drift echo'' events, as well as streaming tailward away from their acceleration site in the near-earth plasma sheet. Most auroral ion acceleration processes occur (or are greatly enhanced) during the time that these global magnetospheric events are occurring in the magnetotail. A qualitative model relating energetic ion populations to near-tail magnetic reconnection at substorm onset followed by …
Date:
January 1, 1985
Creator:
Baker, D.N. & Belian, R.D.
Object Type:
Article
System:
The UNT Digital Library
Quantitative analysis of the hydrothermal system in Lassen Volcanic National Park and Lassen Known Geothermal Resource Area
The Lassen hydrothermal system is in the southern Cascade Range, approximately 70 kilometers east-southeast of Redding, California. The conceptual model of the Lassen system is termed a liquid-dominated hydrothermal system with a parasitic vapor-dominated zone. The essential feature of this model is that steam and steam-heated discharge at relatively high elevations in Lassen Volcanic National Park (LVNP) and liquid discharge with high chloride concentrations at relatively low elevations outside LVNP in the Lassen Known Geothermal Resource Area (KGRA) are both fed by an upflow of high-enthalpy, two-phase fluid within the Park. Liquid flows laterally away from the upflow area towards the areas of high-chloride discharge, and steam rises through a vapor-dominated zone to feed the steam and steam-heated features. The geometric model corresponds to an areally restricted flow regime that connects the Bumpass Hell area in LVNP with regions of chloride hot springs in the Mill Creek canyon in the KGRA south of LVNP. Simulations of thermal fluid withdrawal in the Mill Creek Canyon were carried out in order to determine the effects of such withdrawal on portions of the hydrothermal system within the Park. 19 refs., 17 figs., 4 tabs.
Date:
January 1, 1984
Creator:
Sorey, M.L. & Ingebritsen, S.E.
Object Type:
Report
System:
The UNT Digital Library
Relativistic effects in the atomic and nuclear few-body problems
Relativistic effects in the atomic and nuclear few-body systems are classified and discussed with the emphasis on electromagnetic transitions. The size of relativistic corrections, calculational techniques and ambiguities, and comparison of theory and experiment are considered. 8 figures.
Date:
January 1, 1980
Creator:
Friar, J.L.
Object Type:
Article
System:
The UNT Digital Library
Western Gas Sands Project. Status report, 1 May-31 May, 1980
This report summarizes the progress of the government-sponsored project directed towards increasing gas production from the low permeability gas sands of the western United States. The planning activities for the multi-well experiment continued in May. Bartlesville Energy Technology Center continued formation evaluation and reservoir simulation studies. Lawrence Livermore Laboratory continued calculations of fracturing near interfaces. Los Alamos Scientific Laboratory focused work on the permanent magnet system for NMR logging. Results of the 3-D Seismic Reflection Survey were presented by Sandia Laboratories. Production and injection experiments continued for the Colorado Interstate Gas Company Miller No. 1 and Sprague No. 1 wells. The DOE Well Test Facility was transported to Las Vegas for repairs and modifications. In situ testing continued at the Nevada Test Site for the Sandia Mineback program.
Date:
January 1, 1980
Creator:
unknown
Object Type:
Report
System:
The UNT Digital Library
Microcrystalline silicon growth for heterojunction solar cells. Second quarterly report, 1 April 1983-30 June 1983
In this reporting period, a single source of evaporation with B mixed with highly doped Si was used instead of the co-evaporation of separate Si and B sources. The purpose was to reduce possible carbon contamination. The results of both the heterojunction or heteroface structures, however, were similar to last quarter when evaporation was used. The best Voc of the heterojunction was about 460mV and no improvement in Voc in the heteroface structure, was observed; slight Voc degradation occurred. A study of the p m-Si/p c-Si structure showed a negative Voc in many cases. The highest /sup 0/C voltage was up to -150mV. This indicated that the interface properties between the two materials are such that instead of repelling minority carriers from the substrate carrier, collection actually occurred. This structure defeated the purpose, but it might also mean that n-type m-Si could be beneficial and should be included in future study. Another study of cells made in the part of substrates not covered by m-Si resulted in performance lower than the controls. This indicated possible substrate degradation in the process, the extent of which will be studied in the future.
Date:
January 1, 1983
Creator:
Iles, P. A.; Leung, D. C. & Fang, P. H.
Object Type:
Report
System:
The UNT Digital Library
De-entrainment on vertical elements in air droplet cross flow. [PWR]
De-entrainment phenomena on vertical elements in air-water droplet cross flow are generated using a horizontal array of water spray nozzles and a draft-induced wind tunnel. These conditions are used to obtain experimental values of the de-entrainment efficiency of isolated elements (25.4-, 63.5-, and 101.6-mm-diam cylinders and a 76.2-mm-square tube), and of an array of 101.6-mm-diam cylinders. A flow model is developed that extrapolates the de-entrainment efficiency of isolated elements through the use of a correlation for the interference effect to predict the efficiency of large arrays of similar elements. This simple model is shown to provide a good prediction of the de-entrainment efficiency of arrays in terms of the efficiency of an isolated element.
Date:
January 1, 1980
Creator:
Dallman, J.C. & Kirchner, W.L.
Object Type:
Article
System:
The UNT Digital Library
Catalyst and process development for hydrogen preparation from future fuel cell feedstocks. Quarterly progress report, October 1, 1979-December 31, 1979. [Pt/Rh, Ni/Rh, Ni/Pt/Rh, Ni, Ni/Ru, Ni/Pt, Ni/Co]
Twelve steam reforming catalysts were evaluated using an autothermal reforming screening unit. Duplicate tests were run with two samples to determine test variability. The samples tested contained either base metals, precious metals, or combinations of base and precious metals. The test was capable of distinguishing among samples where gross variations in composition are the main factor; for example, catalysts containing 2% by weight precious metals are more active than catalysts containing 15% by weight nickel. The results show a decrease in hydrocarbon breakthrough as the weight of nickel charged to the constant volume reactor increases. A commercial nickel catalyst, G90C, appears slightly better than some Engelhard prepared samples of equal nickel concentrations due to the higher density of G90C. Visual observation of the used catalysts show that samples containing only precious metals (Pt/Rh) did not coke during the run. The samples containing only base metals (nickel, cobalt) were coked and were magnetic. Samples containing 14.5% nickel by weight with 0.5% precious metals by weight added were not coked, were not magnetic, and had a blue colored core as compared to the black core of the virgin samples. Some speculation about deactivation mechanisms based on these observations are made.
Date:
January 1, 1980
Creator:
Yarrington, R M; Feins, I R; Hwang, H S & Mayer, C P
Object Type:
Report
System:
The UNT Digital Library
Laser-plasma interaction experiments at laser wavelengths of 1. 064. mu. m, 0. 532. mu. m, and 0. 355. mu. m
The effect of laser wavelength on laser-plasma coupling is one of the critical issues facing the laser driven inertial confinement community. The advantages of using lasers with output wavelength less than 1 ..mu..m, such as enhanced absorption and hydrodynamic efficiency, reduction in parametric instabilities and corresponding suprathermal electron generation, have long been predicted theoretically.
Date:
January 1, 1982
Creator:
Campbell, E. M.; Mead, W. C. & Turner, R. E.
Object Type:
Article
System:
The UNT Digital Library
Coordination/management tasks for the IEA and CCMS solar heating and cooling programs
None
Date:
January 1, 1980
Creator:
unknown
Object Type:
Report
System:
The UNT Digital Library
Growth regulation by macrophages
The evidence reviewed here indicates that macrophages, either acting alone or in concert with other cells, influence the proliferation of multiple types of cells. Most of the data indicate that these effects are mediated by soluble macrophage-elaborated products (probably proteins) although the role of direct cell-to-cell contacts cannot be ruled out in all cases. A degree of success has been achieved on the biochemical characterization of these factors, due mainly to their low specific activity in conditioned medium and the lack of rapid, specific assays. Understanding the growth-regulating potential of macrophages is an important and needed area of research.
Date:
January 1, 1982
Creator:
Wharton, W.; Walker, E. & Stewart, C.C.
Object Type:
Article
System:
The UNT Digital Library
Diskless LSI-11 systems
Programs for dedicated LSI-11 based systems can easily be stored in ROM instead of floppy disks, yet execute the same as disk-stored programs. Two sample systems are described.
Date:
January 1, 1982
Creator:
Ford, W. & Shirk, D. G.
Object Type:
Article
System:
The UNT Digital Library
Severe accident core heatup transients in modular high temperature gas-cooled reactors without operating Reactor Cavity Cooling Systems
The ultimate decay heat removal system for the current Modular High Temperature Gas-Cooled reactors is a completely passive natural convection air cooling loop. This paper considers an extremely remote accident scenario, where even this passive system fails, and heat rejection is only via a layer of thermal insulation to the reactor silo structure and the surrounding soil. The results show that even in this case the peak fuel temperatures remain well within safe limits. However, vessel and concrete temperatures can - under extreme circumstances and after several weeks - reach temperature levels at which structural failure becomes possible.
Date:
January 1, 1988
Creator:
Kroeger, P. G.
Object Type:
Article
System:
The UNT Digital Library
Numerical study of the NOL large-scale gap test
The NOL large-scale gap test has been modeled numerically using the LASL reactive hydrodynamics code 2DE with Forest Fire burn rates. The model gives good agreement between calculated and experimental critical gap values for VTQ-2 and Composition B. The calibration of peak pressure in the gap versus gap length has been obtained from these calculations, and is in good agreement with the published experimental curve. The two-dimensional nature of the gap test is evident from the curvature of the shock wave in the gap and test sample, and from the observed distance of run to detonation in the test samples.
Date:
January 1, 1980
Creator:
Bowman, A.L.
Object Type:
Report
System:
The UNT Digital Library