Biological transfer and loss of /sup 36/Cl-labeled DDT in an old-field ecosystem (open access)

Biological transfer and loss of /sup 36/Cl-labeled DDT in an old-field ecosystem

An enclosed 10-acre old-field plot treated in June 1969, with chlorine-36 labeled DDT was sampled each year from 1969 through 1974 to monitor the fate of the insecticide in the soil and biota. In order to provide data on compartmentalization of DDT in the vegetation, invertebrates and vertebrates inhabiting the plot, sampling was carried out to estimate both body burdens of DDT and biomass of populations. Another aspect of this study, the determination of rates of accumulation of residues by invertebrates and vertebrates, has been reported previously (Forsyth and Peterle 1973; Forsyth et al. 1975; Peterle 1975). This report describes (a) temporal patterns of DDT residues in soil and biota from 1969 through 1974 and (b) quantities of DDT held in the soil and biotic compartments of the ecosystem. Part II of the report is concerned with translocation and accumulation of/sup 14/C-DDT.
Date: April 20, 1979
Creator: Peterle, T.J.
Object Type: Report
System: The UNT Digital Library
Confidence level in the calculations of HCDA consequences using large codes. [LMFBR] (open access)

Confidence level in the calculations of HCDA consequences using large codes. [LMFBR]

The probabilistic approach to nuclear reactor safety is playing an increasingly significant role. For the liquid-metal fast breeder reactor (LMFBR) in particular, the ultimate application of this approach could be to determine the probability of achieving the goal of a specific line-of-assurance (LOA). Meanwhile a more pressing problem is one of quantifying the uncertainty in a calculated consequence for hypothetical core disruptive accident (HCDA) using large codes. Such uncertainty arises from imperfect modeling of phenomenology and/or from inaccuracy in input data. A method is presented to determine the confidence level in consequences calculated by a large computer code due to the known uncertainties in input invariables. A particular application was made to the initial time of pin failure in a transient overpower HCDA calculated by the code MELT-IIIA in order to demonstrate the method. A probability distribution function (pdf) for the time of failure was first constructed, then the confidence level for predicting this failure parameter within a desired range was determined.
Date: April 20, 1979
Creator: Nguyen, D. H. & Wilburn, N. P.
Object Type: Article
System: The UNT Digital Library
Development of mullite substrates and containers. Final report, October 7, 1977-April 15, 1979 (open access)

Development of mullite substrates and containers. Final report, October 7, 1977-April 15, 1979

The objective of this program was to evaluate mullite in contact with molten silicon to be used as a substrate for Honeywell's Silicon-On-Ceramic process and as a container for melting solar grade silicon. A further requirement was to fabricate respective substrates and containers. To maintain solar grade silicon purity levels, the mullite must generally introduce less than 10/sup 15/ atoms/cc of impurities. To evaluate the mullite-molten silicon interaction, a series of bodies were made with variations in density, alumina-silica ratio and glass-crystalline ratio. These materials were tested in a sessile drop technique. None of the variations stood up to extended exposure to molten silicon sufficiently to be recommended as a contaner material. However, directional solidification experiments by Jet Propulsion Laboratory suggest that, under proper conditions, contamination of the silicon by mullite containers can be minimized. To improve an already good thermal expansion match between mullite and silicon, compositional variations were studied. Altering of the alumina-silica ratio was determined to give a continuously varying thermal expansion. Thus, a composition can be selected to give the desired thermal expansion match with silicon.
Date: April 20, 1979
Creator: Sibold, J.D. & Wirth, D. G.
Object Type: Report
System: The UNT Digital Library
Dynamic analysis methods for nuclear facilities (open access)

Dynamic analysis methods for nuclear facilities

A comparison is made between three different dynamic analysis methods commonly used in the analysis of nuclear facilities. The methods are applied to a typical non-reactor type nuclear facility; namely, an early configuration of the High Performance Fuel Laboratory which was to have been designed and constructed to house an automated fuel process line on the Hanford Reservation near Richland, Washington. The fuel to be handled was mixed plutonium and uranium in powder and pellet form which, therefore, required design for severe earthquake and tornado conditions. The structure is a two-story reinforced concrete shear wall building with a high bay on one end. The comparison is made for earthquake motion in the lateral horizontal direction only. The first method employs a three degree of freedom spring mass system with the masses lumped at the three floor and roof slab levels. After shears are obtained they are distributed to the shear walls in proportion to their stiffnesses. Floor and roof slabs are assumed rigid but eccentricities are accounted for in the shear distribution. The second method utilizes a pseudo three-dimensional stick model. The shear walls and horizontal floor and roof diaphram are modeled as three dimensional beam elements using the SAP …
Date: April 20, 1979
Creator: Horsager, B. K.
Object Type: Article
System: The UNT Digital Library
MIT LMFBR blanket research project. Quarterly progress report, January 1, 1979--March 31, 1979 (open access)

MIT LMFBR blanket research project. Quarterly progress report, January 1, 1979--March 31, 1979

Progress is summarized in the following areas: fissile build-up in internal blankets, reference cores, and power peaking.
Date: April 20, 1979
Creator: Driscoll, M.J.
Object Type: Report
System: The UNT Digital Library
Near Term Hybrid Passenger Vehicle Development Program. Phase I, Final report. Appendix A: mission analysis and performance specification studies. Volume I (open access)

Near Term Hybrid Passenger Vehicle Development Program. Phase I, Final report. Appendix A: mission analysis and performance specification studies. Volume I

Studies are described which were performed for the Near Term Hybrid Vehicle program to determine passenger car usage patterns and to correlate these trip mission characteristics with vehicle design and performance specifications. (LCL)
Date: April 20, 1979
Creator: Traversi, M. & Barbarek, L.A.C.
Object Type: Report
System: The UNT Digital Library
Texas Register, Volume 4, Number 30, Pages 1409-1450, April 20, 1979 (open access)

Texas Register, Volume 4, Number 30, Pages 1409-1450, April 20, 1979

A weekly publication, the Texas Register serves as the journal of state agency rulemaking for Texas. Information published in the Texas Register includes proposed, adopted, withdrawn and emergency rule actions, notices of state agency review of agency rules, governor's appointments, attorney general opinions, and miscellaneous documents such as requests for proposals. After adoption, these rulemaking actions are codified into the Texas Administrative Code.
Date: April 20, 1979
Creator: Texas. Secretary of State.
Object Type: Journal/Magazine/Newsletter
System: The Portal to Texas History
Development and Organization of White House Conferences. (open access)

Development and Organization of White House Conferences.

This report presents the Development and Organization of White House Conferences. The first White House Conference was held in 1907 whereas the second White House Conference was held in 1909.
Date: April 20, 1978
Creator: Relyea, Harold C.
Object Type: Report
System: The UNT Digital Library
Federal Criminal Code Reform (open access)

Federal Criminal Code Reform

This report is about the Federal Criminal Code Reform
Date: April 20, 1978
Creator: Peter V Gormley
Object Type: Report
System: The UNT Digital Library
Investigation of methods to transfer heat from solar liquid-heating collectors to heat storage tanks. Final report (open access)

Investigation of methods to transfer heat from solar liquid-heating collectors to heat storage tanks. Final report

A study was made of the methods available to transfer heat from the collector to the water storage tank in water heating systems. In counterflow heat exchangers used in double loop water heating systems, it was found to be more important to use a high water flowrate than a high heat transfer fluid flowrate. It was earlier thought to be best to have matched WC/sub p/ (mass flowrate-specific heat) products in the loops. It was shown in this study that the water WC/sub p/ product should be about twice as large as that of the heat transfer fluid. It was found that neither the heat exchanger type nor the size was very critical, so that very simple criteria were adequate in determining optimum heat exchanger size. It was found that there is a definite system size below which one should use a traced tank or a coil in a tank. Equations and optimization criteria were developed for traced tanks or tanks with coils. At present, there is no quantitative understanding of liquid to liquid (direct contact) heat exchangers, though they are clearly quite effective. Draindown systems are discussed, and several appendices are included on heat transfer and other characteristics of …
Date: April 20, 1978
Creator: Horel, J. D. & de Winter, F.
Object Type: Report
System: The UNT Digital Library
Possible variations in atmospheric ozone related to the eleven year solar cycle (open access)

Possible variations in atmospheric ozone related to the eleven year solar cycle

Changes in ozone and other minor constituents resulting from eleven year variations in the solar flux between 180 and 300 nm reported by Heath and Thekaekara (8) are presented. Results were computed using a one-dimensional time dependent model that allows for all major feedbacks and time delays which may result from changing photolysis rates in the O/sub x/--NO/sub x/--HO/sub x/--ClO/sub x/ system. Since the 1950's the chlorine content of the stratosphere has been increasing. The effect of this increase on ozone variability during the last two solar cycles is analyzed. Expected variations in O/sub 3/ resulting from changes in the uv flux are compared to available measurements of total O/sub 3/.
Date: April 20, 1978
Creator: Penner, J.E. & Chang, J.S.
Object Type: Article
System: The UNT Digital Library
Recirculating flow analyses of Intermediate Size Inducer Pump (ISIP) (open access)

Recirculating flow analyses of Intermediate Size Inducer Pump (ISIP)

This report documents the recirculation flow analyses for the Intermediate-Size Inducer Pump (ISIP), from which the primary flowrates through the pump were obtained. The front and rear impeller labyrinth seals, which incorporate stepped pockets with slanted and rounded ribs were checked. These seal design features should minimize the impeller labyrinth seal leakages and also provide excellent shutoff head characteristics.
Date: April 20, 1978
Creator: Hoshide, R.K.
Object Type: Report
System: The UNT Digital Library
Silicon-on-ceramic coating process. Silicon sheet growth development for the Large-Area Silicon Sheet and Cell Development Tasks of the Low-Cost Silicon Solar Array Project. Quarterly report No. 8, December 28, 1977--March 28, 1977 (open access)

Silicon-on-ceramic coating process. Silicon sheet growth development for the Large-Area Silicon Sheet and Cell Development Tasks of the Low-Cost Silicon Solar Array Project. Quarterly report No. 8, December 28, 1977--March 28, 1977

A research program to investigate the technical and economic feasibility of producing solar-cell-quality sheet silicon by coating inexpensive ceramic substrates with a thin layer of polycrystalline silicon is described. The coating methods to be developed are directed toward a minimum-cost process for producing solar cells with a terrestrial conversion efficiency of 12 percent or greater. By applying a graphite coating to one face of a ceramic substrate, molten silicon can be caused to wet only that graphite-coated face and produce uniform thin layers of large-grain polycrystalline silicon; thus, only a minimal quantity of silicon is consumed. A dip-coating method for putting silicon on ceramic (SOC) has been shown to produce solar-cell-quality sheet silicon. This method and a continuous coating process also being investigated have excellent scale-up potential which offers an outstanding cost-effective way to manufacture large-area solar cells. A variety of ceramic materials have been dip-coated with silicon. The investigation has shown that mullite substrates containing an excess of SiO/sub 2/ best match the thermal expansion coefficient of silicon and hence produce the best SOC layers. With such substrates, smooth and uniform silicon layers 25 cm/sup 2/ in area have been achieved with single-crystal grains as large as 4 mm …
Date: April 20, 1978
Creator: Chapman, P.W. Zook, J.D.; Heaps, J D; Maclolek, R B; Koepke, B; Butter, C D & Schult, S B
Object Type: Report
System: The UNT Digital Library
Sulfur resistant methanation catalyst. Final report, July 1, 1975--January 31, 1978 (open access)

Sulfur resistant methanation catalyst. Final report, July 1, 1975--January 31, 1978

The purpose of this work was to develop a catalyst which would methanate a gasified-coal stream without prior sulfur removal. Fifty-eight activity tests have been completed on forty-nine different catalyst compositions which were studied as sulfur-resistant methanation catalysts. Most of the base-metal catalytically-active, transition elements were used to prepare the catalysts. These metals were combined or used singly with carriers such as alumina, silica, chromium oxide, magnesium oxide, magnesium silicate, and magnesium aluminate to provide the test catalysts for this work. In addition, a number of catalysts of identical chemical composition were prepared by several formulation methods. Test conditions, including temperature, gas composition, and steam levels were varied during the course of the work and computer data processing was used to analyze the test results. Two catalysts, namely nickel and chromium on magnesium silicate and nickel and chromium on magnesium aluminate, converted all of the carbon monoxide and part of the carbon dioxide to methane at 500/sup 0/F when reduced with only hydrogen and no sulfur in the process gas. This is equivalent to the performance of nickel-SNG type methanation catalysts. After sulfiding, the nickel--chromium on magnesium silicate catalyst retained a 60 to 80% methanation activity at 1100/sup 0/F with …
Date: April 20, 1978
Creator: Hausberger, A. L. & Kustes, W. A.
Object Type: Report
System: The UNT Digital Library
Texas Attorney General Opinion: H-1157 (open access)

Texas Attorney General Opinion: H-1157

Document issued by the Office of the Attorney General of Texas in Austin, Texas, providing an interpretation of Texas law. It provides the opinion of the Texas Attorney General, John L. Hill, regarding a legal question submitted for clarification; Whether a juvenile probation officer is a peace officer.
Date: April 20, 1978
Creator: Texas. Attorney-General's Office.
Object Type: Text
System: The Portal to Texas History
U.S Taxation of Citizens Working in Other Countries: An Economic Analysis (open access)

U.S Taxation of Citizens Working in Other Countries: An Economic Analysis

This report contains information about the impact of U.S taxes on foreign U.S workers and industries, and the cost on mainland U.S.
Date: April 20, 1978
Creator: Gravelle, Jane G. & Kiefer, Donald W.
Object Type: Report
System: The UNT Digital Library
Variations in the sun and their effects on weather and climate (open access)

Variations in the sun and their effects on weather and climate

Observations on the effects of the solar cycle and solar activity on the earth's climate are reviewed. (GHT)
Date: April 20, 1978
Creator: Roberts, W O
Object Type: Report
System: The UNT Digital Library
Development of Passive Electronic Components for Instrumentation of Improved Geothermal Logging Tools and Components. Semiannual Progress Report. Report No. 1. [For Temperatures Up to 500/sup 0/C] (open access)

Development of Passive Electronic Components for Instrumentation of Improved Geothermal Logging Tools and Components. Semiannual Progress Report. Report No. 1. [For Temperatures Up to 500/sup 0/C]

Research progress is reported on the development of passive components, resistors, capacitors, metallization, and passivation, that will withstand well logging temperatures to 500/sup 0/C and have extremely low temperature coefficients. The lower the temperature coefficients, the more exacting the instrumentation designs can be without elaborate compensation techniques. The method of fabricating the thin film components is that of chemical vapor deposition (CVD) which is a major deviation from the standard approach. The films are grown in a CVD reactor by passing various reactant gases over a heated substrate. The reactor was modified in order to accommodate the gases needed in the deposition of metals. The reactor can be operated over a temperature range of 400/sup 0/C to greater than 1200/sup 0/C, and at any pressure between atmospheric and 1 x 10/sup -3/ torr. Tungsten, tungsten-silicon, and silicon nitride were successfully deposited on oxidized silicon wafers. The tungsten is used for interconnects and capacitor plates, tungsten-silicon is used as a high resistivity material for resistors, and silicon nitride is used as a dielectric for the capacitors and as a passivation layer. The materials are currently being studied in terms of their deposition parameters and electrical characteristics.
Date: April 20, 1977
Creator: Raymond, L. S.; Hamilton, D. J. & Kerwin, W. J.
Object Type: Report
System: The UNT Digital Library
Remote servicing features of two new mirror fusion reactors (open access)

Remote servicing features of two new mirror fusion reactors

Several general approaches to remote servicing are briefly described for the LLL Field Reversed Mirror and Tandem Mirror Fusion reactors. Remote servicing system design considerations for the blanket module are briefly discussed. (RME)
Date: April 20, 1977
Creator: Neef, W.S. Jr.
Object Type: Article
System: The UNT Digital Library
Review of mirror fusion reactor designs (open access)

Review of mirror fusion reactor designs

Three magnetic confinement concepts, based on the mirror principle, are described. These mirror concepts are summarized as follows: (1) fusion-fission hybrid reactor, (2) tandem mirror reactor, and (3) reversed field mirror reactor. (MOW)
Date: April 20, 1977
Creator: Bender, D. J.
Object Type: Article
System: The UNT Digital Library
Texas Attorney General Opinion: H-984 (open access)

Texas Attorney General Opinion: H-984

Document issued by the Office of the Attorney General of Texas in Austin, Texas, providing an interpretation of Texas law. It provides the opinion of the Texas Attorney General, John L. Hill, regarding a legal question submitted for clarification: Whether various supplies are stationery within article 16, section 21 of the Texas Constitution.
Date: April 20, 1977
Creator: Texas. Attorney-General's Office.
Object Type: Text
System: The Portal to Texas History
Basic Research needs in Energy Technologies (open access)

Basic Research needs in Energy Technologies

This report is about the basic research needs in energy technologies
Date: April 20, 1976
Creator: Krebs-Leidecker, Martha & Hack, David B.
Object Type: Report
System: The UNT Digital Library
Boron-filled elastomers (SANL 252-056). [Vinyl copolymer; Viton A fluoroelastomer; physical characteristics] (open access)

Boron-filled elastomers (SANL 252-056). [Vinyl copolymer; Viton A fluoroelastomer; physical characteristics]

A series of boron-filled vinyl copolymer elastomer (VCE) and Viton A fluoroelastomer formulations was prepared and the physical characteristics of the cured formulations determined. Their weight loss on heating to 300/sup 0/C, as determined by two different analytical methods, did not agree. The presence of up to 0.23 percent boric acid in the boron powders used to fill a standard boron-filled VCE elastomer did not appear to affect the physical characteristics of the cured formulation. 7 tables. (auth)
Date: April 20, 1976
Creator: Schneider, R. E. & Hartzel, L. W.
Object Type: Report
System: The UNT Digital Library
Development of all-beryllium riveted structures. [Frustrum; cylinders; cones] (open access)

Development of all-beryllium riveted structures. [Frustrum; cylinders; cones]

Results are presented of a development program aimed at making a full-scale, all-beryllium frustrum by riveted assembly methods. Included are descriptions of the sheet-metal fabrication practices and assembly plans. Results of extensive mechanical testing of both ingot- and powder-source beryllium products that are presented include tensile, notch-tensile, bearing, and shear tests. Although the full-size structure has not been built, examples are given of several conical and cylindrical structures that were made. The largest of these is a 20-in. diameter, 15-in. long cylinder that was roll-formed from one 0.050-in. thick ingot sheet and assembled with 60 countersunk rivets. Tensile testing of riveted flat coupons is also reported as is bulge testing of riveted cylindrical shells. A cost comparison of riveted deep-drawn and powder-source cylinders is made. Results show that when strength and dimensional tolerance requirements are not severe, a riveted assembly approach is warranted. 33 figures, 8 tables. (auth)
Date: April 20, 1976
Creator: Floyd, D. R.; Leslie, W. W.; Miley, D. V. & Nokes, R. W.
Object Type: Report
System: The UNT Digital Library