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High resolution difference schemes for compressible gas dynamics (open access)

High resolution difference schemes for compressible gas dynamics

The advantages and disadvantages of four new high-resolution difference schemes, namely the von Neumann-Richtmyer, Godunovs, MUSCL and Glimms, for mathematically representing physical conditions in compressible gas flows are compared. (LCL)
Date: July 30, 1980
Creator: Woodward, P. & Colella, P.
System: The UNT Digital Library
Quark deconfinement and high energy nuclear collisions (open access)

Quark deconfinement and high energy nuclear collisions

Statistical QCD predicts that with increasing density, strongly interacting matter will undergo a transition to a plasma of deconfined quarks and gluons. High energy heavy ion collisions are expected to permit experimental studies of this transition and of the predicted new state of matter. 22 refs., 6 figs.
Date: July 1, 1986
Creator: Satz, H.
System: The UNT Digital Library
Meson spectroscopy viewed from J//PSI/ decay: Gluonic states at BEPC (open access)

Meson spectroscopy viewed from J//PSI/ decay: Gluonic states at BEPC

The theoretical and experimental status of the search for gluonic states is reviewed. Progress clearly requires much higher statistics studies of J//psi/ decay, as will be possible at the Beijing Electron Positron Collider. 83 refs.
Date: July 1, 1987
Creator: Chanowitz, Michael S.
System: The UNT Digital Library
Methane entrained in geopressured aquifers, Texas Gulf Coast (open access)

Methane entrained in geopressured aquifers, Texas Gulf Coast

Six tests of geopressured aquifers have yielded between 3.6 to 4.5 m/sup 3//m/sup 3/ (20 to 25 scf/bbl) of gas. These low gas concentrations are attributed to high salinities, that in all tests exceeded 100,000 mg/l, but undersaturated conditions cannot be ruled out completely. Research efforts are designed to delineate the geographic and stratigraphic variations in salinity and to recognize regional and local trends so that zones of lower salinity and higher gas concentration can be identified. Moreover, well logs and seismic data are being used to develop methods of detecting low concentrations of free gas in watered-out gas sands and in thin sands that were considered as noncommercial prior to renewed interest in unconventional gas supplies. (MHR)
Date: July 1, 1980
Creator: Morton, R. A.
System: The UNT Digital Library
CP violation in the six-quark model (open access)

CP violation in the six-quark model

Some of the recent work on CP violation in the six-quark model is reviewed.
Date: July 1, 1980
Creator: Wise, M.B.
System: The UNT Digital Library
Direct observations of the primary state of radiation damage of ion-irradiated tungsten and platinum (open access)

Direct observations of the primary state of radiation damage of ion-irradiated tungsten and platinum

A brief summary was presented of all the Cornell work on the primary state of radiation damage in ion-irradiated tungsten and platinum. The primary research tool for all this research was the field-ion microscope (FIM); the FIM was ideally suited for this research because of its excellent atomic resolution and the ability to examine the interior of the specimens, as a result of the field-evaporation effect. This paper summarized, in outline form, the following items: (1) the principal experimental quantities determined from the analyses performed on all the individual depleted zones (DZs) observed; (2) the main experimental programs; (3) a number of the more important results and conclusions concerning the vacancy structure of DZs; and (4) the three-dimensional spatial distribution of self-interstitial atoms around DZs in tungsten which had been irradiated and examined in situ at 10/sup 0/K.
Date: July 1, 1980
Creator: Seidman, D. N.; Current, M. I.; Pramanik, D. & Wei, C. Y.
System: The UNT Digital Library
Excited-state proton-transfer kinetics in 1-naphthol, 1-naphthol-sulfonates, and organometallic complexes (open access)

Excited-state proton-transfer kinetics in 1-naphthol, 1-naphthol-sulfonates, and organometallic complexes

The dissociation of 1-naphthol in aqueous solution occurs so rapidly that the fluorescence from the neutral form, ROH, has been previously described as completely extinguished or hardly noticeable. Apparently nearly all of the fluorescence originates from the naphtholate ion. This paper reports on the proton-transfer characteristics of a series of 1-naphthol compounds, and also reports preliminary data on excited-state proton transfer in an organometallic complex of ruthenium.
Date: July 1, 1980
Creator: Shapiro, S. L.; Winn, K. R. & Clark, J. H.
System: The UNT Digital Library
Future engineering needs of mirror fusion reactors (open access)

Future engineering needs of mirror fusion reactors

Fusion research has matured during the last decade and significant insight into the future program needs has emerged. While some will properly note that the crystal ball is cloudy, it is equally important to note that the shape and outline of our course is discernable. In this short summary paper, I will draw upon the National Mirror Program Plan for mirror projects and on available design studies of these projects to put the specific needs of the mirror program in perspective.
Date: July 30, 1982
Creator: Thomassen, K.I.
System: The UNT Digital Library
Experiment in multiple-criteria energy policy analysis. [Using HOPE (holistic preference evaluation)] (open access)

Experiment in multiple-criteria energy policy analysis. [Using HOPE (holistic preference evaluation)]

An international panel of energy analysts participated in an experiment to use HOPE (holistic preference evaluation): an interactive parametric linear-programming method for multiple-criteria optimization. The criteria of cost, environmental effect, crude oil, and nuclear fuel were considered according to BESOM: an energy model for the US in the year 2000.
Date: July 1, 1980
Creator: Ho, J K
System: The UNT Digital Library
N and. delta. resonances: an experimental review (open access)

N and. delta. resonances: an experimental review

Experimental progress in N and ..delta.. resonances since the Oxford baryon conference is reviewed. The review concentrates on hadronic channels, and on developments of the last one or two years. The topics reviewed include the antiproton lifetime; the ..delta../sup + +/ magnetic moment; measurements of ..pi..N elastic and charge-exchange scattering in the ..delta.. region, the eta n threshold region, and the high-mass region; partial wave analyses of ..pi..N ..-->.. ..pi..N; measurements of two-body inelastic ..pi..N scattering; and isobar analyses of ..pi..N ..-->.. ..pi pi..N. 75 references, 3 figures, 4 tables.
Date: July 1, 1980
Creator: Kelly, R.L.
System: The UNT Digital Library
Synchrotron x-ray study of physisorbed films of mixtures of Ar and Xe on graphite (open access)

Synchrotron x-ray study of physisorbed films of mixtures of Ar and Xe on graphite

Mixtures of Ar and Xe have been studied in most of the submonolayer region of the phase diagram (T,chi,rho), T = temperature, chi = chemical composition, rho = fraction of a monolayer. The basic feature is a large tendency to form ..sqrt.. 3 x ..sqrt.. 3 commensurate alloys (Kr-like structures), but none of the commensurate nor of the incommensurate structures form a chemically ordered alloy at 11 K. Thus the 2D solid can be thought of as a solid consisting of particles of an average size. This allows the study of commensurate-incommensurate phase transition driven by average particle size. The transition is indeed a sharp first order transition taking place through coexisting phases (tau/sub A/ = 1.64 A/sup -1/ and tau/sub B/ = 1.703 A/sup -1/), as was the case for the low temperature pure Kr-system. Another interesting feature is the existence of well correlated liquid-like structures which preserve their correlation over a temperature range of 5 Kelvin or more. This unusual behavior is for chemical compositions where there is coexistence of a commensurate and an incommensurate solid at high temperature.
Date: July 1, 1982
Creator: Bohr, J.; Nielsen, M.; McTague, J. P.; Als-Nielsen, J. & Kjaer, K.
System: The UNT Digital Library
Structural study of multilayered vanadium/nickel superlattices (open access)

Structural study of multilayered vanadium/nickel superlattices

We have studied the microstructure of V/Ni metallic superlattice, using x-ray and neutron diffraction. We find a sharp and broad rocking curves around the first-order Bragg peak, and attribute them to a columnar structure which gives rise to two modulation structures; one the ordinary layered structure within the columns and the other the averaged modulation structure which produces the sharp rocking peak.
Date: July 1, 1985
Creator: Homma, H.; Lepetre, Y.; Murduck, J.M.; Schuller, I.K. & Majkrzak, C.F.
System: The UNT Digital Library
Open cycle OTEC system with falling jet evaporator and condenser (open access)

Open cycle OTEC system with falling jet evaporator and condenser

A configuration for the open cycle (OC) Ocean Thermal Energy Conversion (OTEC) system is presented incorporating a countercurrent falling jet evaporator and a concurrent falling jet condenser. The parameters governing performance of the proposed configuration are discussed and the sizing of equipment for a 100-MWe net power output OC OTEC plant is performed, based on recent experimental falling jet heat and mass transfer results. The performance of an OC OTEC plant with falling jet evaporator-condenser is compared with the Westinghouse conceptual design that uses an open-channel evaporator and a surface condenser. Preliminary calculations indicate that falling jet heat and mass transfer, when applied in the proposed configuration, leads to a very simple and compact plant assembly resulting in substantial capital cost savings.
Date: July 1, 1980
Creator: Kogan, A.; Johnson, D. H.; Green, H. J. & Olson, D. A.
System: The UNT Digital Library
/sup 56/Ni and the light curve of Type I supernova (open access)

/sup 56/Ni and the light curve of Type I supernova

The explanation of SN Type I by radioactive decay of /sup 56/Ni requires a relatively small value of the transparency function M/sub ej//v/sub 9//sup 2/ = 0.22 in units of M/sub solar/'s and 10/sup 9/ cm s/sup -1/ to explain the light curve. A minimum mass of /sup 56/Ni is required to explain the peak and near peak luminosity. Subsequent radioactive decay energy must escape in some other form than optical light in order to explain the rapid early and late time decay. Early ultraviolet and infrared radiation are excluded as sinks of energy by observations. PdV work is excluded by theory. The energy loss due to the escape of gamma rays and ..beta../sup +/'s with the above value of M/sub ej//v/sub 9//sup 2/ gives good agreement with the light curve after maximum, provided essentially all the trapped energy is converted to optical light. The peak of SN 1972e is explained with the above transparency value M/sub ej//v/sub 9//sup 2/ = 0.22 and mass of /sup 56/Ni of 0.25 M/sub solar/ or 0.4 M/sub solar/, and a distance of 3.2 Mpc or 4 Mpc, respectively. These values depend critically upon the prediscovery report of Austin (1972), and the assumption again …
Date: July 24, 1980
Creator: Colgate, S.A. & Petschek, A.G.
System: The UNT Digital Library
Potential of pyroprocessing for partitioning purex wastes (open access)

Potential of pyroprocessing for partitioning purex wastes

The processes are extremely compact. The process reagents are highly resistant to radiation damage and, therefore, can be used to handle short-cooled, highly concentrated waste with negligible degradation. Most reagents can be recycled back through the process many times, thereby minimizing the generation of waste products, and also reducing the process cost. Fission-product wastes are discharged from the process as concentrated, solid wastes, typically in a metal matrix suitable for permanent disposal. Long cooling periods are not needed prior to conversion to a suitable waste form. The recovered actinides are obtained as metals and cen be easily stored or shipped. Pyrochemical processing of nuclear fuels should be considered as a second generation technology.
Date: July 23, 1980
Creator: Coops, M. S. & Sisson, D. H.
System: The UNT Digital Library
Linear accelerators of the future (open access)

Linear accelerators of the future

Some of the requirements imposed on future linear accelerators to be used in electron-positron colliders are reviewed, as well as some approaches presently being examined for meeting those requirements. RF sources for use in these linacs are described, as well as wakefields, single bunches, and multiple-bunch trains. (LEW)
Date: July 1, 1986
Creator: Loew, G.A.
System: The UNT Digital Library
Lawrence Livermore National Laboratory laser-fusion program (open access)

Lawrence Livermore National Laboratory laser-fusion program

The goals of the Laser-Fusion Program at Lawrence Livermore National Laboratory are to produce well-diagnosed, high-gain, laser-driven fusion explosions in the laboratory and to exploit this capability for both military applications and for civilian energy production. In the past year we have made significant progress both theoretically and experimentally in our understanding of the laser interaction with both directly coupled and radiation-driven implosion targets and their implosion dynamics. We have made significant developments in fabricating the target structures. Data from the target experiments are producing important near-term physics results. We have also continued to develop attractive reactor concepts which illustrate ICF's potential as an energy producer.
Date: July 12, 1982
Creator: Ahlstrom, H.G.
System: The UNT Digital Library
Search for narrow states produced in the reaction. pi. /sup -/p. -->. n +. gamma. 's at 13 GeV/c (open access)

Search for narrow states produced in the reaction. pi. /sup -/p. -->. n +. gamma. 's at 13 GeV/c

A double arm lead-glass lead-scintillator calorimeter system was used to search for narrow states, such as the eta/sub c/, produced in the exclusive reactions ..pi../sup -/p ..-->.. ..gamma gamma..n, ..pi../sup -/p ..-->.. ..pi../sup 0/..gamma..n, and ..pi../sup -/p ..-->.. ..pi../sup 0/..pi../sup 0/n at 13 GeV/c. A 90% c.l. upper limit sigma.BR < 260 pb was found for ..gamma gamma.. states with masses from 2.6 to 3.1 GeV/c/sup 2/. Corresponding limits on narrow ..pi../sup 0/..gamma.. and ..pi../sup 0/..pi../sup 0/ states are also given.
Date: July 7, 1980
Creator: Chiang, I. H.; Johnson, R. A. & Kwan, B.
System: The UNT Digital Library
Bubble-chamber experiments on charmed-particle lifetimes (open access)

Bubble-chamber experiments on charmed-particle lifetimes

The three current bubble-chamber experiments on charmed-particle lifetimes are compared. Their most recently released results are discussed.
Date: July 1, 1982
Creator: Field, R.C.
System: The UNT Digital Library
In-situ impurity measurements in PDX Edge plasma (open access)

In-situ impurity measurements in PDX Edge plasma

The surface analysis station of PDX combines several surface analysis techniques (AES, XPS, SIMS) for in-situ measurement of impurity fluxes in the edge-plasma. The major impurities deposited on a sample surface during nondiverted PDX discharges are oxygen, titanium (limiter material) and chlorine. The impurity fluxes measured at different radial positions decreased by a factor of ten from the plasma edge to the wall. The sample surface collecting the impurity ions is located behind a circular aperture. The observed broadening of the deposition profile of Ti relative to the aperture diameter enables an estimate to be made of the ratio of charge state/energy of Ti ions in the edge plasma. Time-resolved analyses of the deposited impurities are presented which indicate that the time behavior for various impurities may be quite different for different impurity species. This aspect is discussed in relation to probable impurity release mechanisms.
Date: July 1, 1980
Creator: Staib, P.; Dylla, H.F. & Rossnagel, S.M.
System: The UNT Digital Library
Numerical analysis of laminar forced convection in a spherical annulus (open access)

Numerical analysis of laminar forced convection in a spherical annulus

Calculations of steady laminar incompressible fluid-flow and heat transfer in a spherical annulus are presented. Steady pressures, temperatures, velocities, and heat transfer coefficients are calculated for an insulated outer sphere and a 0/sup 0/C isothermal inner sphere with 50/sup 0/C heated water flowing in the annulus. The inner sphere radius is 13.97 cm, the outer sphere radius is 16.83 cm and the radius ratio is 1.2. The transient axisymmetric equations of heat, mass, and momentum conservation are solved numerically in spherical coordinates. The transient solution is carried out in time until steady state is achieved. A variable mesh is used to improve resolution near the inner sphere where temperature and velocity gradients are steep. It is believed that this is the first fully two-dimensional analysis of forced flow in a spherical annulus. Local and bulk Nusselt numbers are presented for Reynolds numbers from 4.4 to 440. Computed bulk Nusselt numbers ranged from 2 to 50 and are compared to experimental results from the literature. Inlet flow jetting off the inner sphere and flow separation are predicted by the analysis. The location of wall jet separation was found to be a function of Reynolds number, indicating the location of separation depends …
Date: July 21, 1980
Creator: Tuft, D.B.
System: The UNT Digital Library
Highlights of the heavy ion fusion symposium (open access)

Highlights of the heavy ion fusion symposium

The current status and prospects for inertial confinement fusion based on the use of intense beams of heavy ions will be described in the light of results presented at the International Symposium on Heavy Ion Fusion, (Washington, DC, May 27-29, 1986).
Date: July 1, 1986
Creator: Keefe, D.
System: The UNT Digital Library
Operational, control and protective system transient analyses of the closed-cycle GT-HTGR power plant (open access)

Operational, control and protective system transient analyses of the closed-cycle GT-HTGR power plant

This paper presents a description of the analyses of the control/protective system preliminary designs for the gas turbine high-temperature gas-cooled reactor (GT-HTGR) power plant. The control system is designed to regulate reactor power, control electric load and turbine speed, control the temperature of the helium delivered to the turbines, and control thermal transients experienced by the system components. In addition, it provides the required control programming for startup, shutdown, load ramp, and other expected operations. The control system also handles conditions imposed on the system during upset and emergency conditions such as loop trip, reactor trip, or electrical load rejection.
Date: July 1, 1980
Creator: Openshaw, F.L. & Chan, T.W.
System: The UNT Digital Library
Liquid-metal embrittlement of refractory metals by molten plutonium (open access)

Liquid-metal embrittlement of refractory metals by molten plutonium

Embrittlement by molten plutonium of the refractory metals and alloys W-25 wt % Re, tantalum, molybdenum, and Ta-10 wt % W was studied. At 900/sup 0/C and a strain rate of 10/sup -4/ s/sup -1/, the materials tested may be ranked in order of decreasing susceptibility to liquid-plutonium embrittlement as follows: molybdenum, W-25 wt % Re, Ta-10 wt % W, and tantalum. These materials exhibited a wide range in susceptibility. Embrittlement was found to exhibit a high degree of temperature and strain-rate dependence, and we present arguments that strongly support a stress-assisted, intergranular, liquid-metal corrosion mechanism. We also believe microstructure plays a key role in the extent of embrittlement. In the case of W-25 wt % Re, we have determined that a dealloying corrosion takes place in which rhenium is selectively withdrawn from the alloy.
Date: July 1, 1980
Creator: Lesuer, D. R.; Bergin, J. B.; McInturff, S. A. & Kuhn, B. A.
System: The UNT Digital Library