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FY 90 annual research plan
The National Institute for Petroleum and Energy Research (NIPER) was established by the DOE to perform contract research for government and industrial clients. The emphasis of the DOE program is immediate near- and mid-term concerns of domestic oil and gas producibility. Its primary purpose is to improve the fundamental understanding of domestic oil and gas resources and the chemical, physical, and biological phenomena that govern the occurrence and recovery of these resources in addition to their associated environmental issues. The near-term objective of the DOE program is to maintain access to resources presently being produced in domestic oil and gas fields, and to decrease the rate of decline of domestic production. NIPER projects in chemical flooding, gas injection, steam injection, and microbial EOR address near-term concerns of domestic oil production. Further, problems associated with the utilization of heavier fossil feedstocks are being addressed. The mid-term objective of the DOE program is to maximize the recovery efficiency of discovered oil and gas through improved understanding of the resource and to develop advanced extraction and instrumentation techniques. The objective also emphasizes an expanded understanding of the environment. NIPER projects dealing with the quantification of reservoir heterogeneities, pore structure analysis, and fluid flow …
Date:
January 1, 1990
Creator:
unknown
Object Type:
Report
System:
The UNT Digital Library
The role of mobile ions in fast ion conducting systems and high impact strength ceramics
This report discusses the following topics: Polymeric systems; Lead halide-containing fast ion conducting glasses; Mixed ionic electronic conduction; Plastic crystals; and Mobile ions as a basis for high impact ceramics.
Date:
January 1, 1991
Creator:
Angell, C. A.
Object Type:
Report
System:
The UNT Digital Library
Condensation in a two-phase pool
We consider the case of vapor condensation in a liquid pool, when the heat transfer is controlled by heat losses through the walls. The analysis is based on drift flux theory for phase separation in the pool, and determines the two-phase mixture height for the pool. To our knowledge this is the first analytical treatment of this classic problem that gives an explicit result, previous work having established the result for the evaporative case. From conservation of mass and energy in a one-dimensional steady flow, together with a void relation between the liquid and vapor fluxes, we determine the increase in the mixture level from the base level of the pool. It can be seen that the thermal and hydrodynamic influences are separable. Thus, the thermal influence of the wall heat transfer appears through its effect on the condensing length L*, so that at high condensation rates the pool is all liquid, and at low rates overflows (the level swell or foaming effect). Similarly, the phase separation effect hydrodynamically determines the height via the relative velocity of the mixture to the entering flux. We examine some practical applications of this result to level swell in condensing flows, and also examine …
Date:
January 1, 1991
Creator:
Duffey, R.B. (Brookhaven National Lab., Upton, NY (United States)) & Hughes, E.D. (EG and G Idaho, Inc., Idaho Falls, ID (United States))
Object Type:
Article
System:
The UNT Digital Library
A study of tau decays of the W boson at CDF (Collider Detector at Fermilab)
A report is given of a search for tau decays of the W boson in p{bar p} collisions at {radical}s = 1.8 TeV using the Collider Detector at Fermilab (CDF). A description of a hardware trigger specifically designed to enhance the number of events with tau decays is presented along with the results of a preliminary analysis of data taken during the 1988--89 run of CDF. 10 refs., 4 figs.
Date:
January 3, 1990
Creator:
Gladney, L. D.
Object Type:
Article
System:
The UNT Digital Library
Repetitive, small-bore two-stage light gas gun
A repetitive two-stage light gas gun for high-speed pellet injection has been developed at Oak Ridge National Laboratory. In general, applications of the two-stage light gas gun have been limited to only single shots, with a finite time (at least minutes) needed for recovery and preparation for the next shot. The new device overcomes problems associated with repetitive operation, including rapidly evacuating the propellant gases, reloading the gun breech with a new projectile, returning the piston to its initial position, and refilling the first- and second-stage gas volumes to the appropriate pressure levels. In addition, some components are subjected to and must survive severe operating conditions, which include rapid cycling to high pressures and temperatures (up to thousands of bars and thousands of kelvins) and significant mechanical shocks. Small plastic projectiles (4-mm nominal size) and helium gas have been used in the prototype device, which was equipped with a 1-m-long pump tube and a 1-m-long gun barrel, to demonstrate repetitive operation (up to 1 Hz) at relatively high pellet velocities (up to 3000 m/s). The equipment is described, and experimental results are presented. 124 refs., 6 figs., 5 tabs.
Date:
January 1, 1991
Creator:
Combs, S. K.; Foust, C. R.; Fehling, D. T.; Gouge, M. J. & Milora, S. L.
Object Type:
Article
System:
The UNT Digital Library
(Hadamard Raman imaging)
We have used newly developed holographic notch filters for obtaining both Stokes and anti-Stokes Raman images. The filters can be used as close as {plus minus}70 cm{sup {minus}1} from the Rayleigh line. We have demonstrated that they are insensitive to polarization, have 80% transmission across their clear apertures and block laser light by 10{sup 4}. The devices now have replaced sharp-cut glass filters on our microscope. We have successfully developed multispectral control and display software for the microscope. 4 refs., 3 figs.
Date:
January 1, 1991
Creator:
unknown
Object Type:
Report
System:
The UNT Digital Library
Anion-exchange resin-based desulfurization process
Under DOE Grant No. FG22-90PC90309, the University of Tennessee Space Institute (UTSI) is contracted to further develop its anion-exchange, resin-based desulfurization concept to desulfurize alkali metal sulfates. From environmental as well as economic viewpoints, it is necessary to remove soluble sulfates from the wastes created by flue gas desulfurization systems. In order to do this economically, a low-cost desulfurization process for spent sorbents is necessary. UTSI's anion-exchange resin-based desulfurization concept is believed to satisfy these requirements.
Date:
January 1, 1992
Creator:
Sheth, A.C.; Strevel, S.D. & Dharmapurikar, R.
Object Type:
Report
System:
The UNT Digital Library
Variability of surface fluxes over a heterogeneous semi-arid grassland
Efforts are increasing throughout the research community to improve the predictive capabilities of general circulation models (GCMs). The US Department of Energy's Atmospheric Radiation Measurement (ARM) program has stated its goals as improving the representation and parameterization of cloud radiative forcing and feedbacks in GCMs by a combined modeling and experimental approach. Along with ambient atmospheric conditions, including advection of water vapor and cloud nuclei from other regions, cloud dynamics depend on surface fluxes of heat and water vapor. The lower boundary of the GCM modeling domain, the earth's surface, exerts a strong influence on regional dynamics of heat and water vapor, and the heterogeneity in the surface features can be responsible for generating regional mesoscale circulation patterns. Changes in the surface vegetation due to anthropogenic activity can cause substantial changes in the ratio of sensible to latent heat flux and result in climate changes that may be irreversible. A broad variety of models for representing energy fluxes are in use, from individual leaf and canopy models to mesoscale atmospheric models and GCMs. Scaling-up a model is likely to result in significant errors, since biophysical responses often have nonlinear dependence on the abiotic environment. Thus, accurate and defensible methods for …
Date:
January 1, 1991
Creator:
Barnes, F.J.; Porch, W.; Cooper, D. (Los Alamos National Lab., NM (United States)); Kunkel, K.E. (Illinois Univ., Urbana, IL (United States)); Hipps, L. & Swiatek, E. (Utah State Univ., Logan, UT (United States))
Object Type:
Article
System:
The UNT Digital Library
Capillary liquid chromatography using laser-based and mass spectrometric detection
The research performed during the past year has mainly focused on investigating and minimizing the problems listed below that limit the practical utility of these capillary electrokinetic separation techniques in chemical analysis. (1) Analyses are hindered by poor reproducibility. This is largely a result of complicated and irreproducible capillary wall-solute interactions that often result in adsorption and mobility changes. (2) While the Micellar Electrokinetic Capillary Chromatography technique permits the separations of neutral solutes, hydrophobic compounds are difficult to separate and manipulation of capacity factors is critically important due to a limited elution range. Because of the limited elution range, it is also beneficial to enhance separation selectivity through the use of non-traditional surfactants. (3) The very small solute band volumes require that on-column'' detection be performed (usually optical detection) and this seriously limits detectability. Laser fluorimetry is particularly amenable to on- column detection with these capillary separation technique. We have explored methods of on-column labeling and multi-wavelength detection to expand the utility of this mode of detection. 35 refs., 7 figs.
Date:
January 1, 1991
Creator:
Sepaniak, M.J. & Cook, K.D.
Object Type:
Report
System:
The UNT Digital Library
Evaluation of a Cray performance tool using a large hydrodynamics code
This paper will discuss one of these automatic tools that has been developed recently by Cray Research, Inc. for use on its parallel supercomputer. The tool is called ATEXPERT; when used in conjunction with the Cray Fortran compiling system, CF77, it produces a parallelized version of a code based on loop-level parallelism, plus information to enable the programmer to optimize the parallelized code and improve performance. The information obtained through the use of the tool is presented in an easy-to-read graphical format, making the digestion of such a large quantity of data relatively easy and thus, improving programmer productivity. In this paper we address the issues that we found when the took a large Los Alamos hydrodynamics code, PUEBLO, that was highly vectorizable, but not parallelized, and using ATEXPERT proceeded to parallelize it. We show that through the advice of ATEXPERT, bottlenecks in the code can be found, leading to improved performance. We also show the dependence of performance on problem size, and finally, we contrast the speedup predicted by ATEXPERT with that measured on a dedicated eight-processor Y-MP.
Date:
January 1, 1992
Creator:
Lord, K.M. (Cray Research, Inc., Eagan, MN (United States)) & Simmons, M.L. (Los Alamos National Lab., NM (United States))
Object Type:
Article
System:
The UNT Digital Library
Humic substance formation during wastewater infiltration
Soil infiltration of wastewater effluents is a widely practiced method of treatment and disposal/reuse throughout the world. Renovation of the wastewater results from a wide variety of complex physicochemical and biological processes. One set of processes is speculated to involve the accumulation of organic matter by filtration and sorption followed by formation of humic substances. This humic substance formation can effect the performance of soil treatment systems by contributing to soil pore clogging and reduction in hydraulic capacity, and by yielding reactive substances and an enhancement of purification processes. While there has been a wealth of research into the nature and genesis of humic substances in terrestrial environments, there has been limited research of humic substance formation during soil infiltration of wastewater. The purpose of the research reported herein was to determine if humic substances can form under conditions typical of those present during wastewater infiltration into natural soil systems. This work was conducted during 1989 to 1990 as a collaborative effort between the Centre for Soil and Environmental Research, located in Aas, Norway and the Institute for Water, Soil and Air Hygiene located in Langen, West Germany. 11 refs., 3 figs., 6 tabs.
Date:
January 1, 1991
Creator:
Siegrist, R.L. (Oak Ridge National Lab., TN (United States)); Hildmann-Smed, R.; Filip, Z.K. (Bundesgesundheitsamt (BGA), Langen (Germany). Inst. fuer Wasser-, Boden- und Lufthygiene) & Jenssen, P.D. (Norges Landbrukshoegskole, Aas (Norway). Centre for Soil and Environmental Research)
Object Type:
Article
System:
The UNT Digital Library
Molecular interactions in dilute supercritical mixtures: Molecular dynamics investigation
We performed a series of molecular dynamics simulations aimed at investigating the nature of the microstructure around solute molecules in a supercritical solvent, in the limit of infinite dilution (no solute-solute interactions). The choice of model system (pyrene in supercritical carbon dioxide) and state conditions (5--20 moles/liter; 37{degrees}C and 75{degrees}C) was done so as to match corresponding fluorescence experiments performed at Georgia Tech. 18 refs., 3 figs.
Date:
January 1, 1991
Creator:
Debenedetti, P.G.
Object Type:
Report
System:
The UNT Digital Library
Particle production and spectra in E802 at BNL-AGS
The production of {pi}, K, and protons measured in the E802 spectrometer are studied for p+A and Si+A collisions. Systematic properties of particle spectra and rapidity density distributions are discussed in terms of centrality and reaction system. A detailed comparison of the data to the RQMD model, which employs the experimental acceptance and cuts are presented. 8 refs., 6 figs.
Date:
January 1, 1991
Creator:
Videbaek, F.
Object Type:
Article
System:
The UNT Digital Library
An update on environmental, health and safety issues of interest to the photovoltaic industry
There is growing interest in the environmental, health, and safety issues related to new photovoltaic technologies as they approach commercialization. Such issues include potential toxicity of II--VI compounds; the impacts of new environmental regulations on module manufacturers; and, the need for recycling of spent modules and manufacturing wastes. This paper will review these topics. 20 refs.
Date:
January 1, 1992
Creator:
Moskowitz, P. D.; Viren, J. & Fthenakis, V. M.
Object Type:
Article
System:
The UNT Digital Library
X-ray, soft x-ray, and vuv beam position monitor
An x-ray beam position monitor has been developed and is currently operational at the NIST beamline X-24A of the National Synchrotron Light Source, Upton, NY. It was developed to accurately measure the vertical position of the synchrotron beam and to allow precise positioning of beamline optics. It is an area type monitor positioned 5.6 meters from the Tangent Point and precedes all beamline instrumentation. Vertical beam position is given by the differential photoemission current from two grids mounted on a Macor frame. The monitor also senses the total photon beam flux. 7 refs., 4 figs.
Date:
January 1, 1991
Creator:
Karlin, B.A. (Brookhaven National Lab., Upton, NY (United States)); Cowan, P.L. (Argonne National Lab., IL (United States)) & Woicik, J.C. (National Inst. of Standards and Technology (IMSE), Gaithersburg, MD (United States))
Object Type:
Article
System:
The UNT Digital Library
A design of experiment study of plasma sprayed alumina-titania coatings
An experimental study of the plasma spraying of alumina-titania powder is presented in this paper. This powder system is being used to fabricate heater tubes that emulate nuclear fuel tubes for use in thermal-hydraulic testing. Coating experiments were conducted using a Taguchi fractional-factorial design parametric study. Operating parameters were varied around the typical spray parameters in a systematic design of experiments in order to display the range of plasma processing conditions and their effect on the resultant coating. The coatings were characterized by hardness and electrical tests, image analysis, and optical metallography. Coating qualities are discussed with respect to dielectric strength, hardness, porosity, surface roughness, deposition efficiency, and microstructure. The attributes of the coatings are correlated with the changes in operating parameters.
Date:
January 1, 1992
Creator:
Steeper, T. J. (Du Pont de Nemours (E.I.) and Co., Aiken, SC (United States). Savannah River Lab.); Varacalle, D. J. Jr.; Wilson, G. C. (EG and G Idaho, Inc., Idaho Falls, ID (United States)); Riggs, W. L. II (Tubal Cain Co., Loveland, OH (United States)); Rotolico, A. J. & Nerz, J. E. (Metco/Perkin-Elmer, Westbury, NY (United States))
Object Type:
Article
System:
The UNT Digital Library
The rate dependence of the saturation flow stress of Cu and 1100 Al
The strain-rate dependence of the saturation flow stress of OFHC Cu and 1100 Al from 10{sup {minus}3}s{sup {minus}1} to nearly to 10{sup 12}s{sup {minus}1} is examined. The flow stress above 10{sup 9}s{sup {minus}1} is estimated using Wallace's theory of overdriven shocks in metals. A transition to the power-law behavior {Psi} {approximately} {tau}{sub s}{sup 5} occurs at a strain rate of order 10{sup 5}s{sup {minus}1}. 10 refs., 2 figs.
Date:
January 1, 1991
Creator:
Preston, D.L.; Tonks, D.L. & Wallace, D.C.
Object Type:
Article
System:
The UNT Digital Library
Hot gas desulfurization with oxides of zinc, iron, and vanadium
The objective of this study is to develop an improved sorbent which can reduce H{sub 2}S levels up to 1 ppmv or less, which can stabilize zinc, and produce economically recoverable amounts of elemental sulfur during regeneration. For this purpose, the desulfurization performance of sorbents prepared by the addition of various amounts of V{sub 2}O{sub 5} to the zinc ferrite sorbent is investigated.
Date:
January 1, 1992
Creator:
Akyurtlu, J.F. & Akyurtlu, A.
Object Type:
Article
System:
The UNT Digital Library
Investigation of breached depleted UF sub 6 cylinders
In June 1990, during a three-site inspection of cylinders being used for long-term storage of solid depleted UF{sub 6}, two 14-ton cylinders at Portsmouth, Ohio, were discovered with holes in the barrel section of the cylinders. An investigation team was immediately formed to determine the cause of the failures and their impact on future storage procedures and to recommend corrective actions. Subsequent investigation showed that the failures most probably resulted from mechanical damage that occurred at the time that the cylinders had been placed in the storage yard. In both cylinders evidence pointed to the impact of a lifting lug of an adjacent cylinder near the front stiffening ring, where deflection of cylinder could occur only by tearing the cylinder. The impacts appear to have punctured the cylinders and thereby set up corrosion processes that greatly extended the openings in the wall and obliterated the original crack. Fortunately, the reaction products formed by this process were relatively protective and prevented any large-scale loss of uranium. The main factors that precipitated the failures were inadequate spacing between cylinders and deviations in the orientations of lifting lugs from their intended horizontal position. After reviewing the causes and effects of the failures, the …
Date:
January 1, 1991
Creator:
DeVan, J. H.
Object Type:
Article
System:
The UNT Digital Library
Tokamak and RFP ignition requirements
A plasma model is applied to calculate numerically transport- confinement (n{tau}{sub E}) requirements and steady-state operation tokamak. The CIT tokamak and RFP ignition conditions are examined. Physics differences between RFP and tokamaks, and their consequences for a DT ignition machine, are discussed. The ignition RFP, compared to a tokamak, has many physics advantages, including ohmic heating to ignition (no need for auxiliary heating systems), higher beta, low ignition current, less sensitivity of ignition requirements to impurity effects, no hard disruptions (associated with beta or density limits), and successful operation with high radiation fractions (f{sub RAD} {approximately} 0.95). These physics advantages, coupled with important engineering advantages associated with lower external magnetic fields, larger aspect ratios, and smaller plasma cross sections translate into significant cost reductions for both ignition and power reactor. The primary drawback of the RFP is the uncertainty that the present confinement scaling will extrapolate to reactor regimes. The 4-MA ZTH was expected to extend the n{tau}{sub E} transport scaling data three order of magnitude above ZT-40M results, and if the present scaling held, to achieve a DT-equivalent scientific energy breakeven, Q=1. A basecase RFP ignition point is identified with a plasma current of 8.1 MA and no auxiliary …
Date:
January 1, 1991
Creator:
Werley, K.A.
Object Type:
Article
System:
The UNT Digital Library
Antiproton driven microfission-fusion on closer inspection
A closer look at the energetics of antiproton annihilation in real systems, coupled to hydrodynamics, materials strength, particle transport, equations of state, and related interactions is necessary to assess ultimate viability. The systematics of antiproton microfission-fusion are the subject of this analysis, as well as technology constraints.
Date:
January 1, 1992
Creator:
Wienke, B.R.
Object Type:
Article
System:
The UNT Digital Library
Slit-mounted LED fiducial system for rotating mirror streak cameras
We have developed a fiducial system for rotating mirror streak cameras that utilizes light emitting diodes mounted at the slit position of the camera. The diodes are driven to the required high brightness by a unique pulse power circuit designed to provide high voltage, high current pulses 18 nanoseconds in length at a frequency of up to 2.5 megahertz. The availability of super bright light emitting diodes with a wavelength of 630 to 640 nanometers allows us to record fiducial pulses, at streaking speeds in excess of 20mm per microsecond, on all the black and white films commonly used in high speed photography. The time marks on the film record are referenced to the real time of the experiment from a clock-driver that controls the start and frequency of the fiducial pulse train and by three adjustable and discreet blanked fiducials. This paper discusses the development of this system and describes the full setup as used at LLNL. 6 refs., 4 figs.
Date:
January 1, 1991
Creator:
Shaw, L.L.; Muelder, S.A. & Rivera, A.T.
Object Type:
Article
System:
The UNT Digital Library
Performance of trim coils made by a novel method
A precision, automated method of manufacturing trim coils based on printed circuit technology has been developed. Excellent quench performance and increased radiation resistance have been achieved in recently-tested models of sextupole trim coils developed for operation inside 40 mm-aperture SSC Main Collider dipoles. 6 refs., 2 figs.
Date:
January 1, 1991
Creator:
Wanderer, P.; Anerella, M.; Cottingham, J.; Ganetis, G.; Garber, M.; Ghosh, A. et al.
Object Type:
Article
System:
The UNT Digital Library
Progress in collisions of multiply charged ions
The increasing power and availability of supercomputers during the last decade led to significant progress in the theory of multicharged ion interactions. However, important tests of many theoretical predictions were lacking, and have become possible only quite recently as new capabilities have been realized in the laboratory. This paper broadly surveys some of these experimental developments, and their impact on our understanding of collisional interactions of multicharged ions. The scope is limited to measurements made with monoenergetic beams. 35 refs., 6 figs.
Date:
January 1, 1991
Creator:
Phaneuf, R.A.
Object Type:
Article
System:
The UNT Digital Library