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Novel approaches to the production of higher alcohols from synthesis gas

Description: A detailed technical plan for research on higher-alcohol synthesis in a slurry reactor was prepared and approved internally, as part of the University's requirements for the doctoral degree. The focus of this plan is the high-pressure methanol synthesis catalyst, and modifications thereof. A major challenge of the research will be to identify a slurry medium that is stable at the typical operating temperature ofthis catalyst, i.e., about 400[degrees]C. Two shakedown runs were made in the stirred autoclave without catalyst in order to check the mechanical operation of the system and to test some of the analytical equipment. Further preparation, characterization and screening of higher-oxygenate synthesis catalysts based on rhodium were carried out. The catalyst compositions tested during the period were: Rh/Al[sub 2]O[sub 3], Rh/Nb/Al[sub 2]O[sub 3], Mo/Rh/Al[sub 2]O[sub 3] and W/Rh/Al[sub 2]O[sub 3]. All catalysts contained a nominal 1 wt. % Rh. Rh/Nb/Al[sub 2]O[sub 3] and Rh/Mo/Al[sub 2]O[sub 3] were about twice as active for COconversion as the other catalysts. However, oxygenate yields were disappointing for all of the compositions tested. The Rh/Mo/Al[sub 2]O[sub 3] catalyst had the highest carbon efficiency to oxygenates, 33%.
Date: April 14, 1993
Creator: Roberts, G. & Kow, S.
Partner: UNT Libraries Government Documents Department

TRENDS '90: A compendium of data on global change

Description: This document is a source of frequently used global change data. This first issue includes estimates for global and national CO{sub 2} emissions from the burning of fossil fuels and from the production of cement, historical and modern records of atmospheric CO{sub 2} and methane concentrations, and several long-term temperature records. Included are tabular and graphical presentations of the data, discussions of trends in the data, and references to publications that provide further information. Data are presented in a two-page format, each dealing with a different data set. All data are available in digital form from the Carbon Dioxide Information Analysis Center.
Date: August 1, 1990
Creator: Sepanski, R.J.; Stoss, F.W. (eds.); Boden, T.A.; Kanciruk, P. & Farrell, M.P.
Partner: UNT Libraries Government Documents Department

A discounted-cost continuous-time flexible manufacturing and operator scheduling model solved by deconvexification over time

Description: A discounted-cost, continuous-time, infinite-horizon version of a flexible manufacturing and operator scheduling model is solved. The solution procedure is to convexify the discrete operator-assignment constraints to obtain a linear program, and then to regain the discreteness and obtain an approximate manufacturing schedule by deconvexification of the solution of the linear program over time. The strong features of the model are the accommodation of linear inequality relations among the manufacturing activities and the discrete manufacturing scheduling, whereas the weak features are intra-period relaxation of inventory availability constraints, and the absence of inventory costs, setup times, and setup charges.
Date: August 1, 1990
Creator: Eaves, B.C. & Rothblum, U.G.
Partner: UNT Libraries Government Documents Department

Development, characterization and evaluation of materials for open cycle MHD. Quarterly report for the period ending June 1978

Description: The objectives of this program are directed toward the development and characterization of high temperature ceramics for open-cycle, coal-fired MHD power generators. The current activities are directed to electrode and insulator materials, and include (1) determination of the effects of alkali seed on the behavior of ceramics in a dc electric field; (2) development and testing of improved high temperature ceramic electrodes and insulators with controlled composition, microstructure, and properties; and (3) characterization and evaluation of materials utilized in channels being tested for MHD power generator development. Research is reported on (1) evaluation of metal electrodes from 250 hour MHD test, (2) characterization and properties of USSR MgO insulating wall material, (3) thermal diffusivity/thermal conductivity of electrode and insulator materials, (4) coprecipitation of ceramic powders, (5) properties of yttria chromites, and (6) rare earth hafnates. (WHK)
Date: October 1, 1978
Creator: Bates, J.L.; Marchant, D.D. & Daniel, J.L.
Partner: UNT Libraries Government Documents Department

Toroidal Alfven wave stability in ignited tokamaks

Description: The effects of fusion-product alpha particles on the stability of global-type shear Alfven waves in an ignited tokamak plasma are investigated in toroidal geometry. Finite toroidicity can lead to stabilization of the global Alfven eigenmodes, but it induces a new global shear Alfven eigenmodes, which is strongly destabilized via transit resonance with alpha particles. 8 refs., 2 figs.
Date: January 1, 1989
Creator: Cheng, C.Z.; Fu, G.Y. & Van Dam, J.W.
Partner: UNT Libraries Government Documents Department

International petroleum statistics report for December 1990

Description: This report presents data on international oil production, consumption, imports, exports, and stocks. The report has three sections. Section 1 contains time series on world oil production, and oil consumption and stocks in the Organization for Economic Cooperation and Development (OECD). This section contains annual data beginning in 1973, and monthly data for the most recent two years. Section 2 presents an oil supply/consumption balance for the market economies (i.e. non-communist countries). This balance is presented in quarterly intervals for the most recent two years. Section 3 presents data on oil imports by OECD countries. This section contains annual data beginning in 1982, and quarterly data for the most recent two years.
Date: December 27, 1990
Creator: Available, Not
Partner: UNT Libraries Government Documents Department

Energy and Technology Review, October 1990

Description: This report discuss the following topics: History of Cold Fusion Experiments; LLNL Experiments on Cold Fusion; Roundtable Discussion on Cold Fusion; and Using MeV Ions To Characterize and Modify Materials.
Date: October 1, 1990
Creator: Johnson, K.C.; de Vore, L.; Gleason, K.; Kirvel, R.D. & Sanford, N.M. (eds.)
Partner: UNT Libraries Government Documents Department

Minimum streaming current requirements for MFTF--revised by recent (r/sub p//a/sub i/) scaling in 2XIIB

Description: The minimum warm ion density necessary to effectively stablize the DCLC instability in MFTF represents a significant planning requirement. Thus a review of the theoretical predictions for MFTF stabilization is presented here including the recently revised (a/sub i//r/sub p/) scaling determined from tests with 2XIIB. For the assumptions given the total streaming current requirements range from 1500 to 2800 A, for T/sub e/ predicted from .66 to 1 keV and E/sub i/ approx. 50 keV.
Date: February 14, 1979
Creator: Osher, J.E.
Partner: UNT Libraries Government Documents Department

Improved approximate formulas for flux from cylindrical and rectangular sources

Description: This report provides two new approximate formulas for the flux at detector points outside the radial and axial extensions of a homogeneous cylindrical source and improved approximate formulas for the flux at points opposite rectangular surface sources. These formulas extend the range of geometries for which analytic approximations may be used by shield design engineers to make rapid scoping studies and check more extensive calculations for reasonableness. These formulas can be used to support skeptical, independent evaluations and are also valuable teaching tools for introducing shield designers to complex shield analyses.
Date: March 1, 1993
Creator: Wallace, O.J. & Bokharee, S.A.
Partner: UNT Libraries Government Documents Department

(Acidic deposition and the environment)

Description: The travelers presented several papers at the Fourth International Conference on Acidic Deposition. These covered the following topics: atmospheric chemistry and deposition of airborne nitrogen compounds, soil solution chemistry in high-elevation spruce forests, and forest throughfall measurements for estimating total sulfur deposition to ecosystems. In addition, S. E. Lindberg was invited to organize and chair a conference session on Throughfall and Stemflow Experiments, and to present an invited lecture on Atmospheric Deposition and Canopy Interactions of Metals and Nitrogen in Forest Ecosystems: The Influence of Global Change'' at the 110th Anniversary Celebration of the Free University of Amsterdam.
Date: October 24, 1990
Creator: Garten, C.T.; Lindberg, S.E. & Van Miegroet, H.
Partner: UNT Libraries Government Documents Department

Floating-wire measurements of the magnet used for large-angle pion-nucleus scattering at EPICS

Description: Floating-wire measurements carried out on the circular magnet used for a modification of the EPICS system for large-angle pion-nucleus scattering are described. The region of the incoming pion beam and that of the scattered pion were both covered. The effective radius of the magnet was determined to an uncertainty estimated to be +-1.5 mm. The resulting uncertainty in the scattering angle of the pion in experiments using this system is estimated to be +-0.22/sup 0/, with an upper limit of +-0.50/sup 0/.
Date: August 1, 1984
Creator: Cottingame, W.B.; Burleson, G.R.; Brown, M.; Kiziah, R.; Oakley, D.; Milner, C. et al.
Partner: UNT Libraries Government Documents Department

Catalytic hydrocarbon reactions over supported metals

Description: During the past year we have completed our characterization of the factors that control the structure of fully oxidized W and Mo on silica and have established that support hydroxyl groups play a central role in dispersing and attaching cations to the support oxide. Work with M[sub 2](CO)[sub 4]Cp[sub 2](M[sub 2]=MoMo, WW, MoW) system has been very encouraging and continues to support the notion that it may be possible to control the structure of adsorbed catalysts (in this case generate metal dimers) by use of organometallic precursors. Techniques are being developed necessary to employ XPS as a means to characterize the attachment process and the oxidation state of the cations after various thermal and photolytic reduction steps.
Date: March 29, 1993
Creator: Ekerdt, J.G.
Partner: UNT Libraries Government Documents Department

Evaluation of exposure conditions for the water-side corrosion test of a sodium heated steam generator evaporator model employing a duplex tube (2160 hours at critical heat flux - phase III SSGM tests). [LMFBR]

Description: This report describes the specialized corrosion test water steam loop, test procedures, test conditions, and test results. A complete water chemistry and thermal hydraulic performance history is given and evaluated for the Phase III test program. The movement of the dryout location and the heat flux variations in pre- and post-critical heat flux regions are documented and analyzed. On seven occasions during the course of the test program to date, the operating conditions drifted from the CHF reference Phase III operation in the dryout regime into the DNB regime. The corresponding corrosion mechanism experienced differing exposure conditions on these occasions. CHF sensitivity to this apparent drift behavior is evaluated.
Date: December 1, 1975
Creator: Waszink, R.P.; Hwang, J.Y. & Efferding, L.E.
Partner: UNT Libraries Government Documents Department

Identification of sulfur heterocycles in coal liquids and shale oils. Technical progress report, August 1, 1980-May 1, 1981

Description: The sulfur heterocycle separation scheme which was described in the last progress report was evaluated for quantitative recovery of individual components. The results indicate that recoveries can range from 10% to approx. 30% depending on the structure of the compound. During this period, 23 unsubstituted sulfur-containing heterocyclic ring systems were synthesized in oder to confirm GC/MS identifications and for biological testing. The four possible 3-ring heterocycles and the thirteen possible 4-ring heterocycles were tested for mutagenic activity in the histidine reversion (Ames assay) system. One of the 3-ring isomers, naphtho(1,2-b)-thiophene, and six of the 4-ring isomers induced mutations in Salmonella test strains. One of these compounds, phenanthro(3,4-b)thiophene, displayed approximately the same mutagenic activity as benzo(a)pyrene. A two-step adsorption chromatographic procedure was developed in order to fractionate synthetic fuels into various chemical-type classes for studying the relative concentrations and mutagenic activities of the various types. An SRC-II Heavy Distillate was fractionated into aliphatic hydrocarbons, polycyclic aromatic hydrocarbons, sulfur heterocycles, indoles and carbazoles, azaarenes, and amino polycyclic aromatic hydrocarbons. It was found that the amino-PAH fraction contained most of the mutagenic activity. A survey was made for compounds containing both nitrogen and sulfur heteroatoms in their structures. A number of these compounds were detected by GC using nitrogen- and sulfur-selective detection.
Date: January 1, 1981
Creator: Lee, M. L. & Castle, R. N.
Partner: UNT Libraries Government Documents Department

(Energy and electricity supply and demand)

Description: At the request of the International Atomic Energy Agency (IAEA), representing eleven international agencies which are sponsoring the 1991 Helsinki Symposium on Electricity and the Environment, I traveled to Brussels to participate in the second meeting of one of four advisory groups established to prepare for the Symposium. At the meeting, I was involved in a review of a draft issue paper being prepared for the Symposium and of the Symposium program.
Date: October 9, 1990
Creator: Wilbanks, T.J.
Partner: UNT Libraries Government Documents Department

A novel concept for heat transfer fluids used in district cooling systems

Description: Low-temperature phase-change materials (PCMS) were mixed with water to enhance the performance of heat transfer fluid. Several PCMs were tested in a laboratory-scale test loop to check their suitability to district cooling applications. The phase-change temperatures and latent heats of fusion of tetradecane, pentadecane, and hexadecane paraffin waxes were measured using a differential scanning calorimeter. The heat of fusion of these materials is approximately 60% of that of ice. They exhibit no supercooling and are stable under repeated thermal cycling. For 10% and 25% PCM-water slurries, the heat transfer enhancement was found to be approximately 18 and 30 percent over the value of water, respectively. It was also found that, in the turbulent region, there is only a minor pumping penalty from the addition of up to 25% PCM to the water. It was demonstrated that pentadecane does not clog in a glass-tube chiller, and continuous pumping below its freezing, point (9.9[degrees]C):was successfully carried out in a bench-scale flow loop. Adding PCM to water increases the thermal capacity of the heat transfer fluid and therefore decreases the volume that needs to be pumped in a district cooling system. It also increases the heat transfer rate, resulting in smaller heat exchangers. Research is continuing on these fluids in order to determine their behavior in large-size loops and to arrive at optimum formulations.
Date: January 4, 1991
Creator: Cho, Y.I.; Choi, E. & Lorsch, H.G.
Partner: UNT Libraries Government Documents Department

High magnetic field MHD generator program. Final report, July 1, 1976-December 31, 1979

Description: A theoretical and experimental program was undertaken to investigate MHD channel phenomena which are important at high magnetic fields. The areas studied were inhomogeneity effects, boundary layers, Hall field breakdown and electrode configuration and current concentrations. In addition, a program was undertaken to study steady-state combustion disk and linear channels in an existing 6 Tesla magnet of small dimensions. The structure of the inhomogeneities in the Stanford M-2 was characterized and compared with theoretical results from a linearized perturbation analysis. General agreement was obtained and the analysis was used to compute stability regions for large size generators. The Faraday electrical connection was found to be more stable than the Hall or diagonal wall connections. Boundary layer profile measurements were compared with theoretical calculations with good agreement. Extrapolation of the calculations to pilot scale MHD channels indicates that Hartmann effects are important in the analysis of the sidewall, and Joule heating is important in calculating heat transfer and voltage drops for the electrode wall. Hall field breakdown was shown to occur both in the plasma and through the interelectrode insulator with the insulator breakdown threshold voltage lower than the plasma value. The threshold voltage was shown to depend on the interelectrode gap but was relatively independent of plasma conditions. Experiments were performed at 5.5 Tesla with both disk and linear MHD channels.
Date: April 1, 1980
Creator: Eustis, R. H.; Kruger, C. H.; Mitchner, M.; Self, S. A.; Koester, J. K. & Nakamura, T.
Partner: UNT Libraries Government Documents Department

Enhanced recovery of unconventional gas. Executive summary. Volume I (of 3 volumes)

Description: R and D efforts in enhanced gas recovery of near-conventional and unconventional gas sources are needed in order to augment domestic supplies. Unconventional gas sources could provide 200 to 220 Tcf of additional gas supply, if a combination of economic incentives and publicly sponsored R and D is used, and as much as 2 to 8 Tcf could be delivered per year by 1990. This volume comprises three parts discussing the public policy issues, proposed research strategy in enhanced gas recovery, and methodology. 14 figures. (DLC)
Date: October 1, 1978
Creator: Kuuskraa, V. A.; Brashear, J. P.; Doscher, T. M. & Elkins, L. E.
Partner: UNT Libraries Government Documents Department

Deformation of evaporites near the Waste Isolation Pilot Plant (WIPP) site

Description: Layered evaporite units of Ochoan age in the Delaware Basin are 1000 m thick. They are divided into three stratigraphic units (listed in order of increasing age): the Rustler Formation, the Salado Formation, the Castile Formation. These units, especially the Castile, are deformed along portions of the margin of the Delaware Basin and in some areas internal to the basin. Hypotheses of origin of deformation considered are: gravity foundering; gravity sliding; gypsum dehydration; dissolution; and depositional variations. Gravity foundering and sliding are considered the most probable causes of deformation. However, no hypothesis adequately answers why the deformation has a limited areal distribution. A possible explanation would be areal variations in rock strength caused by variations of intergranular water content. Age and timing of deformation are also crucial. Standard stratigraphic arguments based on superposition may not apply to such a highly incompetent material as halite. Gravity foundering could have happened at any time since deposition including the present; gravity sliding would probably have occurred since basin tilting began in the Cenozoic. Deformation could be ongoing. However, the strain rates are such (10/sup -16/ s/sup -1/) that deformation would progress slowly relative to the facility's time frame of 2.5 x 10/sup 5/ y. Deformation of Salado units would be minimal (<10 m) or nonexistent, but within this time frame, upper anhydrite units of the Castile could fracture and provide the volume for a brine reservoir. Such Volumes would be small (<1%) and would require 10/sup 4/ to 10/sup 6/ y to develop. At these strain rates, fractures that connect the fractured anhydrites of the Castile with the middle Salado could not develop. Deformation should not directly jeopardize the facility over the next 2.5 x 10/sup 5/ y.
Date: March 1, 1983
Creator: Borns, D.J.; Barrows, L.J.; Powers, D.W. & Snyder, R.P.
Partner: UNT Libraries Government Documents Department

GeoProducts WEN-2 well, Wendel-Amedee, California

Description: The GeoProducts WEN-2 well, drilled 2200 feet northwest of Wendel Hot Springs in Lassen County, California, penetrated 4330 feet (1320 meters) of Tertiary basalt flows and volcanoclastics. Production of 251/sup 0/F (122/sup 0/C) thermal fluids comes either from a fault or from intergranular permeability in a 570-foot thick quartzite conglomerate channel overlying the granitic basement rocks at a depth of 4900 feet. The chemistry, temperature and hydrostatic head of the resource in WEN-2 are very similar to that of WEN-1 to the northeast. Unknown faults in the granitic basement rocks, other than the Wendel fault, may be important channelways for the geothermal system. 4 refs., 3 figs.
Date: October 25, 1985
Creator: Sibbett, B.S.
Partner: UNT Libraries Government Documents Department

Waste Isolation Safety Assessment Program: a comparison of evapotranspiration estimates using DOE Hanford climatological data

Description: Three methods of estimating monthly values of evapotranspiration on a year-round basis were compared by using the same set of long-term Hanford climatological data as input. Potential evapotranspiration calculated by all three methods yielded an annual value 5 to 9 times the mean annual precipitation. One method yields a value for actual evapotranspiration and one yields a value for areal evapotranspiration. These are compared on a monthly basis and show quite different distributions over the year. The third method examined is relatively new, was calibrated using data from arid stations, and yields results that may be more truly representative of arid areas like Hanford.
Date: October 1, 1978
Creator: Wallace, R.W.
Partner: UNT Libraries Government Documents Department

Aerated atomization of coal water slurry

Description: In order to better understand the process of slurry atomization, it is important to observe the influence of fluid non-Newtonian rheological behavior on the spray formation process. As a first step, glycerin-water solutions have been atomized. This report describes findings of photographs taken during atomization. 19 figs.
Date: January 5, 1989
Creator: Buckner, H.N.; Sojka, P.E. & Lefebvre, A.H.
Partner: UNT Libraries Government Documents Department

Maywood Interim Storage Site environmental report for calendar year 1989, Maywood, New Jersey

Description: The environmental monitoring program, which began in 1984, was continued in 1989 at the Maywood Interim Storage Site (MISS), a US Department of Energy (DOE) facility located in the Borough of Maywood and the Township of Rochelle Park, New Jersey. MISS is currently used for storage of soils contaminated with low-level radioactivity. MISS is part of the Formerly Utilized Sites Remedial Action Program (FUSRAP), a DOE program to identify and decontaminate or otherwise control sites where residual radioactive materials are present. The monitoring program at MISS measures thoron and radon concentrations in air; external gamma radiation levels; and thorium, uranium, and radium concentrations in surface water, groundwater, and sediment. Additionally, several nonradiological parameters are measured in groundwater. The radiation dose was calculated for a hypothetical maximally exposed individual to verify that the site is in compliance with the DOE radiation protection standard (100 mrem/yr) and to assess its potential effects on public health. This report presents the results of the environmental monitoring program conducted at the US Department of Energy's (DOE) Maywood Interim Storage Site (MISS) during calendar year 1989. Environmental monitoring began at MISS in 1984. 19 refs., 23 figs., 14 tabs.
Date: May 1, 1990
Creator: Available, Not
Partner: UNT Libraries Government Documents Department