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Photoinduced Charge Separation by Polymer-Bound Chromophores

Description: This project has examined the photodynamic behavior of water-soluble polymers that have covalently linked hydrophobic chromophores spaced along the chains. These polymeric systems have been examined for photoinduced charge separation with electron-accepting ions having different total charge. Focus has been on the excited singlet (S{sub 1}) state formed by laser flash absorption. The effects of pH and ionic strength -- factors that govern the conformational nature of the polymer in solution -- … more
Date: September 1, 1991
Creator: Rodgers, M. A. J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Protective coatings and sealants for solar applications

Description: An aging study has been completed which evaluated a number of polymeric materials for potential use as (1) protective coatings for back surfaces of mirrors and (2) solar heliostat edge seals. These investigations were conducted in an artificial weathering chamber that accelerated thermal cycling. The primary mirror failure mode was observed to be silver corrosion resulting from moisture exposure. To increase mirror longevity in current heliostat designs, intimate bonding at all the composite in… more
Date: September 1, 1980
Creator: Wischmann, K. B. & Gonzales, M. H.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Multi-transducer dummy unit evaluation of polystyrene bead foam as an encapsulant for electronic packages

Description: A dummy electronic assembly without electronic components was used to measure loadings and deflections caused by 0.2, 0.3, 0.4, 0.5 and 0.6 g/cm/sup 3/ densities of polystyrene bead foam during fusion and thermal cycling. Previously developed and proven transducers showed that the lower three densities caused low and safe loads and deflections, but that the highest two densities must be used with care for fragile electronic components.
Date: September 1, 1980
Creator: Swanson, G. D.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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A replaceable reflective film for solar concentrators

Description: The 3M Company manufactures a silvered acrylic film called ECP-305 that is regarded as the preferred reflective film for use on stretched-membrane heliostats. However, ECP-305 will degrade in time, due to both corrosion of the silver layer and delamination at the film's silver-to-acrylic interface, and will eventually need to be replaced. 3M uses a very aggressive adhesive on this film, and once it is laminated, replacement is very difficult. The purpose of this investigation was the developmen… more
Date: September 1, 1991
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Corrosion testing of urea-formaldehyde foam insulating material

Description: Two tests of the corrosiveness of urea-formaldehyde (UF) foam insulating materials were compared. One test, the Timm test, had test coupons foamed in place. In the second, the Canadian test, blocks of foam already set were placed in contact with test coupons. The Timm test uses 10 gage thick coupons, while the Canadian test specifies 3 mil thick ones. Two samples of UF foam were tested by the Timm and the Canadian tests. The electrical-resistance probes showed that the corrosion rate against st… more
Date: September 1, 1980
Creator: Weil, R.; Graviano, A. & Sheppard, K.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Polymer concrete patching materials

Description: The increased use of deicing salts is causing rapid deterioration of portland cement concrete bridge decks. Soluble chlorides cause corrosion of the steel reinforcing rods with a corresponding increase in volume of the rods. This expansion causes stresses in the concrete which result in delaminations and surface spalling. The repair of surface spalls with portland cement concrete can only be made if traffic can be avoided for several days. A patching material which would allow traffic to resume… more
Date: September 1, 1977
Creator: Fontana, J.J.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Cryogenic compressive properties of basic epoxy resin systems

Description: The compressive properties of short cylindrical samples of many different epoxy resin systems have been measured at ambient temperature and at 77/sup 0/K. These are pure resin systems of known chemistry, without the inorganic fillers or fibrous reinforcements needed in final cryogenic systems. Of course, chemically incorporated modifiers such as flexibilizing resins have been included. This data should make possible inferences about cryogenic properties from molecular structures and provide spe… more
Date: September 1, 1985
Creator: Markley, F.W.; Hoffman, J.A. & Muniz, D.P.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Decontamination of Cells 6 and 7, Building 3019, Following Plutonium- Release Incident

Description: As a result of the evaporation explosion in the Radiochemical Processing Pilot Plant on Nov. 20, 1959, two cells were contaminated with plutonium to a transferable level of 10/sup 8/ d/m/100 sq cm. The area involved measures 40 by 20 by 27 ft high with a total surface area, including equipment, of 10,000 sq ft. The cells were decontaminated by a factor of 1000 in five months by removing loose equipment, debris, and shielding blocks and flushing with 430,600 liters of various decontaminating rea… more
Date: September 11, 1961
Creator: Parrott, J.R.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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A comparison of the neutron response of CR-39 made by different manufacturers

Description: CR-39 was obtained from American Acrylics and Plastics, Inc. (A.A), N. E. Technology, Ltd. (N.E), and Tech/Ops Landauer, Inc. (LT). The dosemeters were exposed to radioisotopic neutron sources at SLAC, and moderated {sup 252}Cf at ORNL. The A.A. and N.E. dosemeters were electrochemically etched (pre-etch in 6.5 N KOH at 60{degrees}C for 1 hour and 45 minutes, a 5 hour etch at 3000 V and 60 Hz, a 23 minute blow-up step at 2 kHz and a post-etch for 15 minutes). Track densities were determined wit… more
Date: September 1, 1991
Creator: Ipe, N.E.; Liu, J.C. (Stanford Linear Accelerator Center, Menlo Park, CA (United States)); Buddemeier, B.R. (Lawrence Livermore National Lab., CA (United States)); Miles, C.J. (Radiation Detection Co., Sunnyvale, CA (United States)) & Yoder, R.C. (Tech/OPS Landauer, Inc., Glenwood, IL (United States))
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Selective emitter. Task II topical report for radiative-cooling materials

Description: The theoretical basis of the selective emitter is that, if a material emits only in the 8-13 micron interval, it will absorb only in the same interval. After a survey of several candidate materials, the silicon oxynitride system was found to have better optical properties than previously used materials as well as economic feasibility, and efforts to acquire a sample are described. Other promising materials are described: polyvinylidene fluoride (Tedlar), silicon monoxide, silicon dioxide, and s… more
Date: September 20, 1981
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

State-of-the-art report on low-level radioactive waste treatment

Description: An attempt is made to identify the main sources of low-level radioactive wastes that are generated in the United States. To place the waste problem in perspective, rough estimates are given of the annual amounts of each generic type of waste that is generated. Most of the wet solid wastes arise from the cleanup of gaseous and liquid radioactive streams prior to discharge or recycle. The treatment of the process streams and the secondary wet solid wastes thus generated is described for each type… more
Date: September 1, 1980
Creator: Kibbey, A. H. & Godbee, H. W.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Solar-heated municipal swimming pools, a case study: Dade County, Florida

Description: The experience of installing a solar energy system to heat the water in the swimming pool in one of Dade County, Florida's major parks is described and the mechanics of solar heated swimming pools are explained. The solar heating system consists of 216 unglazed polypropylene tube collectors, a differential thermostat, and the distribution system. The performance and economics of the system are discussed as well as future plants. (LEW)
Date: September 1, 1981
Creator: Levin, M.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Low level waste treatment by ion-exchange. II. Use of a weak acid, carboxylic-phenolic ion-exchange resin

Description: Laboratory results are presented for a flowsheet study of a process for decontaminating ORNL low level waste water. The water is adjusted to approximately pH 12 with NaOH, clarified, and passed through a bed of phenolic cation exchange resin. This study, using a phenolic-carboxylic resin, showed essentially the same results as those previously reported using a phenolic-sulfonic resin, i.e., radioactivities in ORNL waste were reduced to the order of 10% of MPC. The phenolic-carboxylic resin has … more
Date: September 25, 1961
Creator: Holcomb, R.R. & Roberts, J.T.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Biological and clinical dosimetry. Progress report, October 1, 1980-September 30, 1981

Description: A second measurement of the event size distribution for 20 MeV neutrons was carried out at Ohio University to determine the reproducability of results. Again a significant difference between measurement and theoretical calculations by Caswell and Coyne was found. The measured fraction of events due to alpha particles was significantly lower than that predicted by the calculation of Casell and Coyne. Furthermore, the discrepancies with the theoretical calculations made by Caswell and Coyne were … more
Date: September 30, 1981
Creator: Laughlin, J. S. & Zeitz, L.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Development of improved insulation materials. Final technical report, September 1,1978-September 30, 1979

Description: Evaluations of three types of silicone foam, on which Dow Corning holds patent rights, for use as insulation in flat plate solar collectors. The three types of foam were: Type IA: a two part, room temperature curing foam cross-linked through identical with SiOSi identical with linkages; Type IB: a one-part, heat activated foam also crosslinked through identical with SiOSi identical with bonds; and Type II: a two-part, room temperature curing foam cross-linked with =NCOS(CH/sub 2/)/sup 3/ identi… more
Date: September 1, 1979
Creator: Rabe, J A; Spells, S; Homan, G R; Rasch, D M; Lee, C L & Parmele, R C
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Evaluation and performance of the special wasteform lysimeters at a humid site

Description: The Savannah River Laboratory has been evaluating the leaching/migration behavior of commercial power reactor wasteforms by the use of lysimeters operated under field conditions at a humid site. These lysimeters model the conditions in actual burial trenches. Wasteforms comprising Portland cement, masonry cement, and vinyl ester-styrene polymer wasteforms were emplaced in the lysimeters in March 1982. Effluent water has been analyzed on a regular basis since that time. Cs-137, Sr-90, and/or Co-… more
Date: September 1, 1985
Creator: Oblath, S B & Hoeffner, S L
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Laser cutting of Kevlar laminates

Description: An investigation has been conducted of the use of laser energy for cutting contours, diameters, and holes in flat and shaped Kevlar 49 fiber-reinforced epoxy laminates as an alternate to conventional machining. The investigation has shown that flat laminates 6.35 mm thick may be cut without backup by using a high-powered (1000-watt) continuous wave CO/sub 2/ laser at high feedrates (33.87 mm per second). The cut produced was free of the burrs and delaminations resulting from conventional machin… more
Date: September 1977
Creator: VanCleave, R. A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Comparison of the effect of outdoor exposure on the optical properties of solar mirrors and transparent encapsulant materials

Description: The effects of outdoor exposure on solar mirrors and transparent encapsulant materials are assessed and compared. The encapsulant materials tested included glasses, polymers and silicones. Samples of the materials were placed on stationary exposure racks in six locations that represented urban, desert, oceanside and high altitude mountain areas. Samples were removed periodically for optical characterizations. The spectral hemispherical and diffuse reflectance of the mirror samples and the spect… more
Date: September 1, 1981
Creator: Dake, L.S.; Lind, M.A. & Maag, C.R.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Cross Section Evaluation Working Group benchmark specifications. Volume 2. Supplement

Description: Neutron and photon flux spectra have been measured and calculated for the case of neutrons produced by D-T reactions streaming through a cylindrical iron duct surrounded by concrete. Measurements and calculations have also been obtained when the iron duct is partially filled by a laminated stainless steel and borated polyethylene shadow bar. Schematic diagrams of the experimental apparatus is included.
Date: September 1, 1986
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Cementing of geothermal wells. Progress report No. 6, July--September 1977

Description: A coordinated program for the development of improved cements specifically designed for geothermal well applications was started in April 1976. Since that time an assessment of the state of the art of well cementing has been made, a management plan prepared, and research on organic and inorganic cementing materials started.
Date: September 1, 1977
Creator: Kukacka, L. E.; Fontana, J.; Zeldin, A.; Carciello, N. & Sugama, T.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Cross-section sensitivity analyses for a Tokamak Experimental Power Reactor

Description: The objectives of this report were (1) to determine the sensitivity of neutronic responses in the preliminary design of the Tokamak Experimental Power Reactor by Argonne National Laboratory, and (2) to develop the use of a neutron-gamma coupled cross-section set in the calculation of cross-section sensitivity analysis. Response functions such as neutron plus gamma kerma, Mylar dose, copper transmutation, copper dpa, and activation of the toroidal field coil dewar were investigated. Calculations… more
Date: September 1, 1977
Creator: Simmons, E.L.; Gerstl, S.A.W. & Dudziak, D.J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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US/French joint research program regarding the behavior of polymer base materials subjected to beta radiation: Volume 2, Phase-2a screening tests: (Final report)

Description: As part of the ongoing joint NRC/CEA cooperative test program to investigate the relative effectiveness of beta and gamma irradiation to produce damage in polymer base materials, ethylene propylene rubber (EPR) specimens, in slab geometry, were exposed to Cobalt-60 gamma rays and accelerator produced electron beams. Specimens were irradiated and evaluated at research facilities in the US (Sandia National Laboratories) and France (Compagnie ORIS Industrie). These tests included several electron … more
Date: September 1, 1987
Creator: Buckalew, W.H.; Wyant, F.J.; Chenion, J.; Carlin, F.; Gaussens, G.; Le Tutour, P. et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Development of nanostructured and surface modified semiconductors for hybrid organic-inorganic solar cells.

Description: Solar energy conversion is increasingly being recognized as one of the principal ways to meet future energy needs without causing detrimental environmental impact. Hybrid organic-inorganic solar cells (SCs) are attracting particular interest due to the potential for low cost manufacturing and for use in new applications, such as consumer electronics, architectural integration and light-weight sensors. Key materials advantages of these next generation SCs over conventional semiconductor SCs are … more
Date: September 1, 2008
Creator: Hsu, Julia, W. P.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Potential application of microsensor technology in radioactive waste management with emphasis on headspace gas detection.

Description: Waste characterization is probably the most costly part of radioactive waste management. An important part of this characterization is the measurements of headspace gas in waste containers in order to demonstrate the compliance with Resource Conservation and Recovery Act (RCRA) or transportation requirements. The traditional chemical analysis methods, which include all steps of gas sampling, sample shipment and laboratory analysis, are expensive and time-consuming as well as increasing worker's… more
Date: September 1, 2004
Creator: Davis, Chad Edward; Thomas, Michael Loren; Wright, Jerome L.; Pohl, Phillip Isabio; Hughes, Robert Clark; Wang, Yifeng et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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