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Radon transport in dry, cracked soil: Two-dimensional, finite element model

Description: A two-dimensional finite element code, CRACK, simulates the effect of changes in surface air pressure on radon concentration in soil with parallel, partially penetrating cracks. A sensitivity analysis investigates the effect of changes in crack dimensions, soil characteristics, and surface air pressure on radon flux to the atmosphere from a dry, cracked soil. Radon flux is found to be most sensitive to changes in soil properties: the diffusion coefficient is most important, followed by permeabi… more
Date: December 1, 1989
Creator: Holford, D. J. (Pacific Northwest Lab., Richland, WA (USA)); Schery, S. D.; Wilson, J. L. & Phillips, F. M. (New Mexico Inst. of Mining and Technology, Socorro, NM (USA))
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Streamflow, specific-conductance, and temperature data for Bayou and Little Bayou Creeks near Paducah, Kentucky, August 15 and 16, 1989

Description: Discharge, temperature, and specific conductance measurements were made August 15 and 16, 1989, at 74 main channel sites and seven tributaries on Bayou and Little Bayou Creeks in the vicinity of the Paducah Gaseous Diffusion Plant. These measurements were made during base flow conditions to provide data for analysis of the interaction of surface and ground water. The discharge of Bayou Creek was 0.30 cubic feet per second (ft{sup 3}/s) at the most upstream site, and 5.8 ft{sup 3}/s at the most … more
Date: December 31, 1989
Creator: Evaldi, R. D. & McClain, D. L.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Applications of computer modeling to fusion research. Progress report, 1988--1989

Description: Progress achieved during this report period is presented on the following topics: Development and application of gyrokinetic particle codes to tokamak transport, development of techniques to take advantage of parallel computers; model dynamo and bootstrap current drive; and in general maintain our broad-based program in basic plasma physics and computer modeling.
Date: December 31, 1989
Creator: Dawson, J. M.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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In-place testing summary (1989)

Description: Periodic evaluation of an air-cleaning system is necessary in order to establish a record of its current operating condition. These evaluations along with Health Physics air sampling determine whether air-cleaning integrity is being maintained. The in-place test is conducted in most instances without disrupting plant operations, and only if the systems failed the test would it become necessary to shut down. Testing is conducted on single and multi-stage filter systems and other filtration devic… more
Date: December 31, 1989
Creator: Ortiz, J. P.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Burning of a spherical fuel droplet in a uniform subsonic flowfield

Description: An analytical/numerical model is described for the evaporation and burning of a spherical fuel droplet in a subsonic crossflow. The external gaseous flowfield is represented using an approximate compressible potential solution, while the internal flowfield of the droplet is represented by the classical Hill`s spherical vortex. This allows numerical solution for the external boundary layer and diffusion flame characteristics to be made, from which the droplet`s effective drag coefficient, rate o… more
Date: December 31, 1989
Creator: Madooglu, K. & Karagozian, A. R.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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A parallel multigrid method for data-driven multiprocessor systems

Description: The multigrid algorithm (MG) is recognized as an efficient and rapidly converging method to solve a wide family of partial differential equations (PDE). When this method is implemented on a multiprocessor system, its major drawback is the low utilization of processors. Due to the sequentiality of the standard algorithm, the fine grid levels cannot start relaxation until the coarse grid levels complete their own relaxation. Indeed, of all processors active on the fine two dimensional grid level … more
Date: December 31, 1989
Creator: Lin, C. H.; Gaudiot, J. L. & Proskurowski, W.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Electrochemical abatement of pollutants NO{sub x} and SO{sub x} in combustion exhaust gases employing a solid-oxide electrolyte. Fourth quarterly report, July 1989--September 1989

Description: During the fourth quarter of this grant, the major accomplishment concerns the spectroscopic investigation of oxygen vacancies in YSZ and ESB. The nature of electrolytic ``blackening`` was studied. It was found that the same reduction processes that turn polycrystalline YSZ black turn single crystals orange. Two absorption bands attributable to this orange coloration, 328 and 470 nm, were observed. The 328 nm absorption band agrees with theoretical calculations for an F-center YSZ. Several fluo… more
Date: December 31, 1989
Creator: Stevenson, D. A. & Frank, C. W.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Permeability Changes in Coal Resulting From Gas Desorption. Quarterly Report, August 16, 1989--November 15, 1989

Description: The goal of this task is to accurately measure the elongation and shrinkage exhibited by coal as it sorbs and desorbs methane gas at elevated pressure. Our research group has discussed several possible methods to measure this strain, including: optical microscopy, laser interferometry, conventional strain gauges, and LVDT strain gauges. There are advantages and disadvantages of each method. We had planned to use optical microscopy but, on further investigation, this approach will be less satisf… more
Date: December 31, 1989
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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High beta and second region stability analysis and ICRF edge modeling. Progress report, March 15, 1988--May 14, 1989

Description: This report describes the tasks accomplished under Department of Energy contract {number_sign}DE-FG02-86ER53236 in modeling the edge plasma-antenna interaction that occurs during Ion Cyclotron Range of Frequency (ICRF) heating. This work has resulted in the development of several codes which determine kinetic and fluid modifications to the edge plasma. When used in combination, these code predict the level of impurity generation observed in experiments on the experiments on the Princeton Large … more
Date: December 31, 1989
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Performance of asynchronous algorithms in multi-level data-driven systems

Description: Asynchronous algorithms are efficient methods in solving scientific and engineering problems. Much research has been devoted to the study of asynchronous algorithms in different areas. This paper will show asynchronous algorithms applied to logic circuit simulation, communication networks, partial differential equations (PDE) and artificial neural networks, and as well as implementations of these asynchronous algorithms on a special class of multiprocessor systems, namely Multi-level Tagged-tok… more
Date: December 31, 1989
Creator: Gaudiot, J. L. & Lin, C. M.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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[Genetics and biochemistry of surfactant synthesis in Rhodococcus sp. H13-A]. Final report

Description: The rationale for these studies resides is that biosurfactant synthesis occurs only when cells are grown with alkanes as sole source of carbon and energy. It is reasoned that biosurfactant synthesis is linked genetically to alkane oxidation and that the identification and characterization of the alk genes would provide information about the structural and regulator genes involved, in biosurfactant synthesis. Rhodococcus H13-A chromosomal DNA was isolated and digested with the restriction endonu… more
Date: December 31, 1989
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Volcanic studies at Katmai

Description: The Continental Scientific Drilling Program (CSDP) is a national effort supported by the Department of Energy, the US Geological Survey, and the National Science Foundation. One of the projects proposed for the CSDP consists of drilling a series of holes in Katmai National Park in Alaska to give a third dimension to the model of the 1912 eruption of Novarupta, and to investigate the processes of explosive volcanism and hydrothermal transport of metals (Eichelberger et al., 1988). The proposal f… more
Date: December 31, 1989
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Research on the Seasonal Snow of the Arctic Slope. Annual Progress Report, January 1, 1989--December 31, 1989

Description: This project deals with the seasonal snow on Alaska`s Arctic Slope. Although it is concentrated on snow of the R40 project area, it is important to relate the snow cover of this area with the rest of the Arctic Slope. The goals include determination Of the amount of precipitation which comes as snow, the wind transport of this snow and its depositional pattern as influenced by drifting, the physical properties of the snow, the physical processes which operate in it, the proportions of it which … more
Date: December 31, 1989
Creator: Benson, C. S.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Parallel computing: One opportunity, four challenges

Description: The author reviews briefly the area of parallel computer processing. This area has been expanding at a great rate in the past decade. Great strides have been made in the hardware area, and in the speed of performance of chips. However to some degree the hardware area is beginning to run into basic physical speed limits, which will slow the rate of advance of this area simply because of physical limitations. The author looks at ways that computer architecture, and software applications, can work… more
Date: December 31, 1989
Creator: Gaudiot, J.-L.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Chemical reactions of excited nitrogen atoms for short wavelength chemical lasers. Final technical report

Description: Accomplishments of this program include the following: (1) Scalable, chemical generation of oxygen atoms by reaction of fluorine atoms and water vapor. (2) Production of nitrogen atom densities of 1 {times} 10{sup 1}5 cm{sup {minus}3} with 5% electrical efficiency by injecting trace amounts of fluorine into microwave discharged nitrogen. (3) Production of cyanide radicals by reaction of high densities of N atoms with cyanogen. (4) Production of carbon atoms by reaction of nitrogen atoms with cy… more
Date: December 15, 1989
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

[Generic ecosystem model for assessing the effects of elevated carbon dioxide on ecosystems]. [Annual] report, July 1, 1988--June 30, 1989

Description: Development of simulation models of the effects of elevated CO{sub 2} on plant physiological processes requires close cooperation between modelers and experimentalists. In particular, the detailed process-based, leaf-level photosynthesis model currently in development at San Diego State University requires parameterization data for different plant species, levels within the canopy, and growth conditions. Validation of model predictions will require additional data. The purpose of this supplemen… more
Date: December 31, 1989
Creator: Reynolds, J. F.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Alkali/TX{sub 2} catalysts for CO/H{sub 2} conversion to C{sub 1}-C{sub 4} alcohols. Technical progress report, March 1989--August 1989

Description: Ruthenium disulfide catalysts have been synthesized, tested, and characterized during this period of research. It was observed that both the undoped and Cs-doped RuS{sub 2} catalysts produced alcohols and lower amounts of hydrocarbons from H{sub 2}/CO = 1.0 synthesis gas at temperatures above 300{degree}C. Calcination and catalytic testing resulted in partial reduction of the RuS{sub 2} to Ru{sup o}. Calcination under H{sub 2}S prevented the partial reduction of the RuS{sub 2} catalyst, but sub… more
Date: December 31, 1989
Creator: Klier, Kamil; Herman, Richard G.; Bastian, Roy D. & Flanagan, Kelly L.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

ALT-II progress report and proposal, December 1989--December 1990

Description: The Advanced Limiter Test (ALT-11) is a joint international program among the United States, the Federal Republic of Germany, and Japan to investigate the performance of a toroidal belt pump limiter in a tokamak, to investigate the behavior of the plasma edge, and to relate edge behavior to overall core energy and particle confinement. The experiments are carried out in the TEXTOR tokamak at KFA Juelich, Federal Republic of Germany. The ALT-II experiment was installed in TEXTOR in 1987 with the… more
Date: December 31, 1989
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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