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Porous graphite air-bearing components as applied to machine tools (open access)

Porous graphite air-bearing components as applied to machine tools

None
Date: January 1, 1974
Creator: Rasnick, W. H.; Arehart, T. A.; Littleton, D. E. & Steger, P. J.
System: The UNT Digital Library
Analysis of Paraho oil shale products and effluents: an example of the multi-technique approach (open access)

Analysis of Paraho oil shale products and effluents: an example of the multi-technique approach

Inorganic analysis of solid, liquid and gaseous samples from the Paraho Semiworks Retort was completed using a multitechnique approach. The data were statistically analyzed to determine both the precision of each method and to see how closely the various techniques compared. The data were also used to determine the redistribution of 31 trace and major elements in the various effluents, including the offgas for the Paraho Retort operating in the direct mode. The computed mass balances show that approximately 1% or greater fractions of the As, Co, Hg, N, Ni, S and Se are released during retorting and redistributed to the product shale oil, retort water or product offgas. The fraction for these seven elements ranged from almost 1% for Co and Ni to 50 to 60% for Hg and N. Approximately 20% of the S and 5% of the As and Se are released. The mass balance redistribution during retorting for Al, Fe, Mg, V and Zn was observed to be no greater than .05%. These redistribution figures are generally in agreement with previous mass balance studies made for a limited number of elements on laboratory or smaller scale pilot retorts. 7 tables.
Date: June 10, 1979
Creator: Fruchter, J. S.; Wilkerson, C. L.; Evans, J. C. & Sanders, R. W.
System: The UNT Digital Library
Schemes for anti pp interactions at ISABELLE (open access)

Schemes for anti pp interactions at ISABELLE

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.
System: The UNT Digital Library
Comments on septa and other small production angle magnets (open access)

Comments on septa and other small production angle magnets

A discussion is given of possible septum magnet parameters for small production angle experiments in the ISABELLE storage rings. Superconducting septa and torroidal septa are also considered. (PMA)
Date: August 25, 1977
Creator: Allinger, J.; Danby, G. & Jackson, J.
System: The UNT Digital Library
Applications of induction linac technology to heavy ion fusion (open access)

Applications of induction linac technology to heavy ion fusion

Evaluation of the application of heavy ion accelerators to ignite d-t pellets in a thermonuclear reactor is discussed. Accelerator design requirements considered include transport-limited current, beam injection conditions, and pulse bunching and focusing characteristics. The desirability of resonant and non-resonant accelerating structures is comparatively examined. The required power system switch tubes are discussed. It is concluded that heavy ion accelerators could offer a promising solution to the pellet-igniter problem. The advantages pointed out for this approach include electric efficiency greater than 10 percent, the possibility of high repetition rates (1 to 10 Hz), and a mature technological base. (RME)
Date: July 1, 1977
Creator: Faltens, A. & Keefe, D.
System: The UNT Digital Library
Sintering of polycrystalline ionic conductors:. beta. ''-Al/sub 2/O/sub 3/ and NASICON (open access)

Sintering of polycrystalline ionic conductors:. beta. ''-Al/sub 2/O/sub 3/ and NASICON

The densification kinetics for both ..beta..''-alumina and NASICON are dramatically different. ..beta..''-Alumina sinters by a reactive liquid process whereas NASICON densifies by a solid state method. More importantly, a qualitative examination of particle and agglomerate distributions, phase composition, linear shrinkage analysis, and heating rate effects can result in a concise determination of sintering processes without recourse to more quantitative techniques. Such a simple procedural method should be a basis for any beginning investigative study into the densification mechanism of new multicomponent ceramic materials.
Date: January 1, 1979
Creator: McEntire, B. J.; Miller, G. R. & Gordon, R. S.
System: The UNT Digital Library
Tumor production in Syrian hamsters following inhalation of PuO/sub 2/--ZrO/sub 2/ aerosol (open access)

Tumor production in Syrian hamsters following inhalation of PuO/sub 2/--ZrO/sub 2/ aerosol

Syrian golden hamsters of both sexes were exposed to aerosols of ZrO/sub 2/ containing PuO/sub 2/. The starting material in the aerosol generator also had a small amount of /sup 57/Co added as a tracer. The mixture of all three constituents was nebulized and the droplets passed through a heating column at 1000/sup 0/C. Aerosol sampling was accomplished with a cascade impactor and electrostatic precipitator. The median aerodynamic diameters in all inhalation runs were approximately 2 ..mu..m with a geometric standard deviation of 2. One exposed group of 60 hamsters had 6-day lung burdens averaging 100 nCi. This group had a lung tumor incidence of 44% with an even distribution of adenomas and carcinomas. Two other groups had average 6-day lung burdens of 80 to 90 nCi plus 55 nCi of intravenously injected spheres localized in the lung. These animals had tumor incidences of approximately 30%.
Date: January 1, 1978
Creator: Thomas, R. G. & Smith, D. M.
System: The UNT Digital Library
/sup 16/O + /sup 40/Ca inelastic scattering and the elastic scattering wave function (open access)

/sup 16/O + /sup 40/Ca inelastic scattering and the elastic scattering wave function

The /sup 16/O + /sup 40/Ca inelastic scattering has been measured at 60-MeV incident energy, and evidence has been found in support of an explicit coupling between direct and elastic channels. The measurements were extended over a large angular range and in particular to very forward angles. The ratio of cross sections between extreme forward and backward angles proved very useful in studying the underlying reaction mechanism.
Date: January 1, 1977
Creator: Rehm, K.E.; Henning, W.; Erskine, J.R. & Kovar, D.G.
System: The UNT Digital Library
Approach to decision modeling for an ignition test reactor (open access)

Approach to decision modeling for an ignition test reactor

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.
System: The UNT Digital Library
Effects of light intensity and PH on photosynthesis in Elodea densa (open access)

Effects of light intensity and PH on photosynthesis in Elodea densa

None
Date: August 1, 1975
Creator: Weber, J.A. & Gates, D.M.
System: The UNT Digital Library
Heavy mass states (open access)

Heavy mass states

The indirect evidence for the production of a heavy lepton and direct evidence for the product of a new hadronic state or states in proton-proton interactions is considered for the interpretation requiring the existence of two more leptons and two new quarks. It is shown that such a picture is consistent and in good agreement with existing data. The new structure is located at M = 9.54 GeV/c/sup 2/ and is much wider than the experimental resolution. Also it is asymmetric, suggesting the presence of several resonances. 7 references. (JFP)
Date: August 23, 1977
Creator: Paschos, E. A.
System: The UNT Digital Library
Compatibility testing of vitrified waste forms (open access)

Compatibility testing of vitrified waste forms

An experimental program to evaluate candidate metals for use in the fabrication of canisters for long-term storage of vitrified radioactive wastes is described. The long-term compatibility of the candidate metal both with the contained vitrified radioactive waste and with the external environments expected in possible final storage locations will be determined. These tests involve heating combinations of waste forms and canister metals in intimate contact for up to 50,000 hr to accelerate any reactions that occur.
Date: March 6, 1978
Creator: Rankin, W.N.
System: The UNT Digital Library
Cryogenic supplies for the TFTR neutral beam line cryopanels (open access)

Cryogenic supplies for the TFTR neutral beam line cryopanels

Cryocondensing panels will be used for the Neutral Beam Lines of the TFTR to satisfy a pumping speed requirement of 2.5 x 10/sup 6/ l/s. The cryocondensing panels are fed by liquid helium (LHe), boiling at selectable temperatures of 4.5/sup 0/K or 3.8/sup 0/K. Liquid nitrogen (LN/sub 2/) panels and chevrons thermally shield the LHe panel. The closed-loop LHe supply system and the open loop LN/sub 2/ system are discussed. The helium refrigerator of minimum 1070-W capacity, together with its distribution system, and the nitrogen distribution system in the ton/hour LN/sub 2/ range is presented. Problems and their solutions in connection with the LHe system, including the distribution over a distance of 500 feet of large quantities of liquid/gas mixtures with load variations over the range of about 3 : 1, and the economies of various types of distribution lines (passive, pumped, shielded, combined), are described. The system design passed the preliminary phase. Design features and auxiliary equipment to assure dispersion of large quantities of nitrogen into the atmosphere and to permit operation under degraded cryogenic helium refrigerator performance are also discussed in Design Considerations.
Date: January 1, 1977
Creator: Pinter, G.
System: The UNT Digital Library
Discussion: ''toughness variations during the tempering of a plain carbon martensitic steel'' by J. E. King, R. F. Smith and J. F. Knott. Retained austenite and transgranular tempered martensite embrittlement (open access)

Discussion: ''toughness variations during the tempering of a plain carbon martensitic steel'' by J. E. King, R. F. Smith and J. F. Knott. Retained austenite and transgranular tempered martensite embrittlement

Discussion is presented to substantiate, clarify and reinterpret some of the results of the above authors for the existence and origin of tempered martensite embrittlement (TME) in relation to retained austenite, with reference to the experimental steels worked at LBL for the past several years.
Date: June 1, 1977
Creator: Rao, B.V.N. & Thomas, G.
System: The UNT Digital Library
Thorium fuel cycles for LWRs: fuel diversion assessments and recycle requirements (open access)

Thorium fuel cycles for LWRs: fuel diversion assessments and recycle requirements

A number of fuel cycles have been proposed for evaluation in the nonproliferation alternative systems assessment program. Among these systems are light water reactors (LWR) operating on the thorium-uranium cycle or the plutonium-thorium cycle either inside or outside energy centers. These proposals support the President's nuclear power policy of accelerating research into alternative fuel cycles that do not permit direct access to materials usable for nuclear weapons but still retain the benefits of nuclear power. Reprocessing and refabrication (often referred to as the ''back cycle'') constitute a portion of the overall fuel cycle and represent potential access points to fissionable materials, which, in many cases, may be in a rather attractive form for diversion. These operations for LWR thorium-uranium and plutonium-thorium fuels were analyzed to assess and rate the diversion or proliferation potential of each major operation. Reprocessing and refabrication evaluations per se constitute insufficient data for rating the acceptability of an entire fuel cycle and must be considered along with reactor analysis, environmental data, resource utilization, and political factors. Each back cycle operation has been evaluated according to needed development, material location, material description, convertibility and radiation hazard. Needed development relates to the state of the art of the …
Date: January 1, 1978
Creator: Carter, W. L.; Rainey, R. H. & Johnson, D. R.
System: The UNT Digital Library
First order study for an iron core OH system for TNS (open access)

First order study for an iron core OH system for TNS

A simple comparison has been made between an air core and an iron core ohmic heating system for a particular device, and it was shown that the peak power requirements can be substantially reduced by the use of an iron core to power levels handled by industry today. It was also shown that for an ohmic heating system initiated plasma that the cost of the iron core ohmic heating power system (iron core, dual rectifier, and DC switch) is less than the cost for a subset of the power system for an air core system (dual rectifier and DC switch). There is considerable work being done on other methods of initiating the plasma none of which seem to be incompatible with the use of an iron core system.
Date: January 1, 1977
Creator: Ballou, J. K. & Schultz, J.
System: The UNT Digital Library
Experimental program to validate analyses of accelerator breeder concepts (open access)

Experimental program to validate analyses of accelerator breeder concepts

The concept of using high-energy particle accelerators to produce neutrons for converting fertile material to fissile is over 25 years old. It is only relatively recently that accelerator design has progressed to a point where the operation approaches commercial viability. Critical unknowns in the concept were identified in a detailed study of specic configurations. Experiments to elucidate these unknowns in a timely manner using existing material and facilities are defined and identified. Basic measurements are described to evaluate effects of the primary particle beam and resulting secondary particles in massive assemblies of most materials of interest.
Date: January 1, 1977
Creator: Talbert Jr., W. L.; Russell, G. J. & Malenfant, R. E.
System: The UNT Digital Library
Light Absorption and Scattering Mechanisms in Laser Fusion Plasmas (open access)

Light Absorption and Scattering Mechanisms in Laser Fusion Plasmas

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 spectra due to resonance absorption are described, as are effects of plasma outflow. We then discuss two regimes where stimulated scattering may occur. Brillouin scattering is expected in the underdense target blow-off, for long laser pulses, and is limited by ion heating. Raman scattering in the background gas of a reactor target chamber is predicted to be at most a 10 percent effect for 1 ..mu..m lasers.
Date: October 4, 1977
Creator: Barnes, C.; Estabrook, K. G.; Kruer, W. L.; Langdon, A. B.; Lasinski, B. F.; Max, C. E. et al.
System: The UNT Digital Library
Measurement of energy loss in the region of relativistic rise for particle identification (open access)

Measurement of energy loss in the region of relativistic rise for particle identification

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 analysis is given in which the counting gas, the pressure, and the maximum allowable particle rate are considered as variables.
Date: January 1, 1977
Creator: Fischer, J.; Okuno, H. & Walenta, A.H.
System: The UNT Digital Library
High-energy proton radiation damage of high-purity germanium detectors (open access)

High-energy proton radiation damage of high-purity germanium detectors

Motivated by their applicability to gamma-ray spectroscopy experiments in space, quantitative studies of radiation damage effects in high-purity germanium detectors due to high-energy charged particles have been initiated with the irradiation by 6 GeV/c protons of two 1.0 cm thick planar detectors maintained at 88/sup 0/K. The threshold for resolution degradation and the annealing characteristics differs markedly from those previously observed for detectors irradiated by fast neutrons. Under proton bombardment, degradation in the energy resolution was found to begin below 7 x 10/sup 7/ protons/cm/sup 2/, and increased proportionately in both detectors until the experiment was terminated at a total flux of 5.7 x 10/sup 8/ protons/cm/sup 2/, equivalent to about a six year exposure to cosmic-ray protons in space. At the end of the irradiation, the FWHM resolution measured at 1332 keV stood at 8.5 and 13.6 keV, with both detectors of only marginal utility as a spectrometer due to the severe tailing caused by charge trapping. The two detectors displayed a significant difference in proton damage sensitivity, which is consistent with fast neutron damage effects. To ensure that detector variability did not influence the comparison of proton- and neutron-induced damage effects, one of the detectors had been used …
Date: October 1, 1977
Creator: Pehl, R.H.; Varnell, L.S. & Metzger, A.E.
System: The UNT Digital Library
Conceptual design of a superconducting magnet coil for the large coil program. [Flat-wound NbTi coils] (open access)

Conceptual design of a superconducting magnet coil for the large coil program. [Flat-wound NbTi coils]

A conceptual design for a toroidal field (TF) coil for a six coil test array has been developed. The electromagnetic, cryogenic, structural, manufacturing, quality assurance and verification testing requirements have been analyzed. The bore is oval shaped and is 2.35 meters horizontally and 3.35 meters vertically. The coil is designed to operate at 8T peak field at rated current of 10450 amperes when the other 5 coils in the toroidal array are at 80% rated current. Using-flat-wound NbTi conductor this pool-boiling, pancake wound coil is fully cryostable, and is enclosed in a 316LN stainless steel coil structure and helium container capable of supporting all expected in-plane loads and out-of-plane loads due to pulsed fields and unsymmetrical current distributions in the other 5 coils.
Date: January 1, 1977
Creator: Quay, R.; Bryant, R. W.; Koenig, R. F.; Ferrante, J. J.; Linkinhoker, C. L.; Donato, J. W. et al.
System: The UNT Digital Library
Review of recent measurements of charmed particle lifetimes using emulsions (open access)

Review of recent measurements of charmed particle lifetimes using emulsions

This talk is a review of results which have been reported during the past year on charmed particle decays in emulsions.
Date: December 1, 1979
Creator: Voyvodic, L.
System: The UNT Digital Library
Proceedings of the symposium on experiments using enriched antiproton, polarized proton, and polarized antiproton beams at Fermilab energies (open access)

Proceedings of the symposium on experiments using enriched antiproton, polarized proton, and polarized antiproton beams at Fermilab energies

The conference included 10 papers, one of which appeared previously under conference number Conf: 770675-1. Separate abstracts were prepared for the remaining nine papers. (JFP)
Date: June 10, 1977
Creator: Yokosawa, A. (ed.)
System: The UNT Digital Library
Tellurium interference in /sup 129/I activation analysis (open access)

Tellurium interference in /sup 129/I activation analysis

Measurement of /sup 129/I at low levels is required for effluent control, environmental assessment and tracer studies in the natural environment. Low level /sup 129/I analysis has also been used for measurement of natural-fission-produced /sup 129/I in minerals and ores as well as meteorites. The most sensitive method for /sup 129/I measurements is neutron activation analysis of iodine separated from a suitable sample. Minimum sample processing prior to neutron activation is desirable in order to reduce chances of sample contamination with uranium or /sup 129/I. A potential interference in the activation analysis method is the production of /sup 129/I (/sup 130/I) from Te impurities in the irradiated ampoule. Procedures have been developed and applied to measurement of the magnitude of the potential Te interference. One-tenth of a microgram of Te in the irradiated ampoule is sufficient to produce interference in the analysis. This is detectable by either radiochemical Te measurements or by /sup 131/I detection in the iodine fraction from the irradiated ampoule. This paper discusses the procedures and results of Te interference studies in /sup 129/I activation analysis. The interference was found to be insignificant for most analyses. 5 tables.
Date: September 20, 1979
Creator: Kaye, J. H.; Brauer, F. P. & Strebin, Jr., R. S.
System: The UNT Digital Library