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Responsive copolymers for enhanced petroleum recovery. Quarterly technical progress report, December 21, 1994--March 22, 1995

Description: The purpose of this study is to extend the concept of micellar polymerization to more complex systems, and to explore the responsive nature of hydrophobically modified polyelectrolytes by tailoring the microstructure. The synthesis of hydrophobically modified acrylamide/acrylic acid copolymer is described. These types of polymers are of interest as thickening agents utilized in enhanced oil recovery.
Date: May 1, 1995
Creator: McCormick, C. & Hester, R.
Partner: UNT Libraries Government Documents Department

FOR STIMUL-RESPONSIVE POLYMERS WITH ENHANCED EFFICIENCY IN RESERVOIR RECOVERY PROCESSES

Description: This report contains a series of terpolymers containing acrylic acid, methacrylamide and a twin-tailed hydrophobic monomer that were synthesized using micellar polymerization methods. These polymer systems were characterized using light scattering, viscometry, and fluorescence methods. Viscosity studies indicate that increasing the nonpolar character of the hydrophobic monomer (longer chain length or twin tailed vs. single tailed) results in enhanced viscosity in aqueous solutions. The interactions of these polymers with surfactants were investigated. These surfactants include sodium dodecyl sulfate (SDS), cetyl trimethyl ammonium bromide (CTAB), Triton X-100. Viscosity measurements of DiC{sub 6}AM and DiC{sub 8}AM mixtures indicate little interaction with SDS, gelation with CTAB, and hemimicelle formation followed by polymer hydrophobe solubilization with Triton X-100. The DiC{sub 10}Am terpolymer shows similar interaction behavior with CTAB and Triton X-100. However, the enhanced hydrophobic nature of the DiC{sub 10} polymer allows complex formation with SDS as confirmed by surface tensiometry. Fluorescence measurements performed on a dansyl labeled DiC{sub 10}Am terpolymer in the presence of increasing amounts of each of the surfactant indicate relative interaction strengths to be CTAB>Triton X-100>SDS. A modified model based on Yamakawa-Fujii and Odjik-Skolnick-Fixman theories was found to describe the contribution of electrostatic forces to the excluded volume of a polyelectrolyte in solution. The model was found to be valid for flexible polymer coils in aqueous salt solutions where intermolecular interactions are minimal. The model suggested that a dimensionless group of parameters termed the dimensionless viscosity should be proportional to the dimensionless ratio of solution screening length to polyion charge spacing. Several sets of experimental data from the literature and from our laboratory have been analyzed according to the model and the results suggest that the two dimensionless groups are indeed related by a universal constant. This model has identified the parameters that are important to fluid mobility, thereby revealing ...
Date: March 26, 2004
Creator: McCormick, Charles & Hester, Roger
Partner: UNT Libraries Government Documents Department

Technical Division quarterly progress report, January 1--March 31, 1978

Description: Fuel Cycle Research and Development: Results are presented on the fluidized-bed calcination of simulated waste from the reprocessing of spent commercial nuclear fuel, on the post-treatment of the resultant calcine, and on the use of bidentate extractants for the separation of actinide elements from the high-level waste prior to calcination. In addition, the development of storage technology for krypton-85 waste, and the behavior of RuO/sub 2/ in fluidized-bed combustion of HTGR fuel are reported. Special Materials Production: Reported are the long-term management of defense waste from the ICPP, the chemistry and pilot plant-studies on the removal of actinides and mercury from ICPP first cycle raffinate, the calcined solids retrieval and handling of ICPP waste stored in vaults, and the preparation of environmental impact statements on options given the Defense Waste Document. Process improvements are given on the Fluorinel headend process for zircaloy-clad fuel and on methods for uranium accountability. Other development results reported are on the Rover process for graphite based fuels, on the calcination of sodium-bearing waste, Fluorinel waste, tank WM-183 waste, and electrolytic process waste. Assistance to the Waste Calcination Process Plant is reported as well as support to the New Waste Calcination Process and methods for the monitoring of gaseous effluents. Other Projects Supporting Energy Developments: Results are reported on nuclear materials security, the behavior of liquid-solid fluidized-bed heat exchangers, in-plant reactor source term measurements, burnup methods for fast breeder reactor fuels, absolute thermal fission yields, analytical support to light water breeder reactor development, and species of iodine in the environment. Research on analytical methods cover iodine-129 in calciner feed, computing room improvements, stack gas sampling for particulates, analysis of glassified calcined waste, and specific components in various materials.
Date: July 1, 1978
Creator: Slansky, C.M. (ed.)
Partner: UNT Libraries Government Documents Department

RADIOISOTOPE AND RADIATION APPLICATIONS. Quarterly Progress Report

Description: Exploratory and optimization experiments in the use of in-process isotope neutron sources to produce short-lived intrinsic radiotracers were initiated. Flux determinations using manganese sulfate solutions and indium foils were performed. The maxtmum thermal-neutron flux measured by indium acttvation was found to be 9.6 x 10/sup 4/ n/(cmsup 2/) (sec) for a 10-curie polonium-beryllium source. The peak flux occurred 3.2 cm from the center of the source through approximately 1.6 cm of water moderator. The study of the mechanism of formation of free radicals in polymeric materials was continued. Again, emphasis was placed on an examination of the effects of structure and molecular weight on the efficiency of free-radical formation in acrylate and methacrylate polymers. In addition, the investtgation of tbe potential application of this information to thc development of graft copolymers was continued. (auth)
Date: January 18, 1962
Creator: Sunderman, D.N. ed.
Partner: UNT Libraries Government Documents Department

RADIOISOTOPE AND RADIATION APPLICATIONS. Quarterly Progress Report

Description: The study of the formation mechanism of free radicals in polymeric materials was continued. Emphasis was placed on an examination of the effect of structural factors on the efficiency of free-radical site formation in acrylate polymers. Site measurements as a function of dose were made for polymethacrylamide and repeated for polymethacrylic acid. The volatile products from the irradiation of polyacrylic acid. polymethacrylic acid, poly-ter- butylmethacrylate. and polycyclohexyl methacrylate were measured quantitatively by mass spectrometry and vapor-phase chromatography. Grafting studies were initiated using polymethylmethacrylate as base polymer and vinylpyrrolidone as graft monomer. (auth)
Date: July 18, 1961
Creator: Sunderman, D.N. ed.
Partner: UNT Libraries Government Documents Department

RADIOISOTOPE AND RADIATION APPLICATIONS QUARTERLY PROGRESS REPORT. SECTION I. USE OF INTRINSIC RADIOACTIVE TRACERS FOR PROCESS CONTROL. SECTION II. RADIATION-INDUCED GRAFT-POLYMERIZATION STUDIES

Description: Research was continued in the areas of intrinsic radioactive tracers for industrial process control and the influence of structural factors in radiation- induced graft polymerization. The use of in-process isotope neutron soarces to produce short-lived radiotraces is discussed. A 10c Po--Be neutron source was obtained for exploratory experiments. The design and construction of a neutronsource storage shield and an activatioa-cell holder are underway. The effect of structural factors oii the eIficiency of free-radical site formation in acrylate and methacrylate polymers was emphasized. Site measurements versus dose were made for poly-n-hexylmethacrylate. Two additional methods for measuring free-radical conceiitrations, a chemical method employing diphenylpicrylhydrazyl and hydroquinone and a method based on molecular-weight decreases, were developed. The grafting studies were continued. (M.C.G.)
Date: October 23, 1961
Creator: McFarling, J.L.; Gluck, P.; Kircher, J.F.; Sunderman, D.N.; Sliemers, F.A.; Luttinger, M. et al.
Partner: UNT Libraries Government Documents Department

Degradation of cellulosic biomass and its subsequent utilization for the production of chemical feedstocks

Description: Progress in studies on the production of reducing sugars and other products by Clostridium thermocellum on cellulosic biomass is reported. The rate of reducing sugar production using corn residue was found to be equal if not greater than on solka floc. Current work is being devoted towards elucidating discrepancies between reducing sugar analysis and high pressure liquid chromatography sugar analysis in order to permit accurate material balances to be completed. Studies are reported in further characterizing the plasmics of C. thermocellum and in the development of protoplasts of the same microorganism. A process and economic analysis for the production of 200 x 10/sup 6/ pounds (90 x 10/sup 6/ kilograms) per year of soluble reducing sugars from corn stover cellulose, using enzymes derived from Clostridium thermocellum was designed. Acrylic acid was produced in resting cell preparation of Clostridium propionicum from both ..beta..-alanine and from propionic acid. Results from the conversion of corn stover hydrolyzates to lactic acid, a precursor to acrylic acid, show that up to 70% of the sugars produced are converted to lactic acid. Efforts are proceeding to improve the conversion yield and carry out the overall conversion of corn stover to acrylic acid in the same fermentor. Results on the production of acetone and butanol by Clostridium acetobutylicum demonstrated the capability of the strain to produce mixed solvents in concentration and conversion similar to that achieved in industrial processes. Various studies on the production of acetic acid by Clostridium thermoaceticum are also reported.
Date: November 1, 1977
Creator: Wang, D.I.C.; Cooney, C.L.; Demain, A.L.; Gomez, R.F. & Sinskey, A.J.
Partner: UNT Libraries Government Documents Department

Degradation of cellulosic biomass and its subsequent utilization for the production of chemical feedstocks. Progress report, March 1, 1977--May 31, 1977

Description: The degradation of cellulosic biomass continues to focus on the anaerobic thermophile Clostridium thermocellum. When grown on crystalline cellulose (MN300) in batch culture, there is an initial rapid accumulation of reducing sugars but the sugars are rapidly metabolized in later times during the fermentation. When grown on Solka floc with periodic addition of the substrate, there is a continual accumulation of reducing sugars (xylose, glucose, and cellobiose) as well as ethanol and acetic acid during the entire course of the fermentation. In the presence of surfactant in the growth medium, there is an increased appearance of extracellular cellulases. A chemically defined medium is being developed for growth Cl. thermocellum in order to study the enzyme regulations. Lastly, a trinitrophenyl-carboxylmethyl cellulose substrate for determining cellulose activity appears to be a promising and rapid assay. Progress in the genetic manipulations has been cautious but promising. Preliminary evidence leads to optimistic projection on the presence of plasmids and bacteriophage in Cl. thermocellum. The production of chemical feedstocks continues to focus on acrylic acid, acetone/butanol and acetic acid. Studies with cell free extracts of Clostridium propionicum have shown the production and accumulation of acrylic acid from lactic acid. The use of electron acceptor in cell-free systems has shown effective prevention on the reduction of acrylic acid to propionic acid. Medium development and strain selection using available acetone/butanol producing Cl. acetobutylicum have been initiated. There is every indication that these strains are capable to produce mixed solvents close to the theoretical maximum yield. An accurate and rapid method for quantifying acetic acid was developed. This technique is being used to examine the pertinent parameters on the production of acetic acid by Clostridium thermoaceticum.
Date: June 1, 1977
Creator: Wang, D.I.C.; Cooney, C.L.; Demain, A.L.; Gomez, R.F. & Sinskey, A.J.
Partner: UNT Libraries Government Documents Department

Performance testing of the Acurex solar-collector Model 3001-03

Description: Results are summarized of tests conducted at the Collector Module Test Facility on an Acurex Model 3001-03 Parabolic Trough Concentrating Solar Collector. Test temperaure range was 100/sup 0/C to 300/sup 0/C. Tests were conducted with the collector axis oriented east-west and again with the collector axis oriented north-south. Three collectors were tested: one using polished aluminum mirrors, one using glass mirrors, and another using an aluminized acrylic film mirror.
Date: March 1, 1982
Creator: Dudley, V.E. & Workhoven, R.M.
Partner: UNT Libraries Government Documents Department

Recovery of anaerobic digestion after exposure to toxicants. Final report

Description: The concept that methane fermentation cannot tolerate chronic or slug doses of toxicants has almost totally precluded methane fermentation as a viable contender for the treatment of industrial wastewaters. This study assayed a wide variety of toxicants, heavy metals, inorganic salts, organic chemicals, solvents, and antibiotics which are used in industrial processes and, therefore, appear in the industrial wastewaters therefrom. Toxicity was related to the reduction in methane production of a control containing no toxicant. The response of methane fermentation after exposure to a toxicant was assayed with unacclimated cultures as well as cultures which had been acclimated to increasing concentrations of the toxicant over long periods of time. The reversible nature of the toxicants was assayed by adding slug doses to plug flow anaerobic filters and recording gas production prior to, during, and after toxicant addition.
Date: December 1, 1979
Creator: Yang, J.; Parkin, G. F. & Speece, R. E.
Partner: UNT Libraries Government Documents Department

Degradation of cellulosic biomass and its subsequent utilization for the production of chemical feedstocks. Progress report, June 1-August 31, 1978

Description: Studies concerning the cellobiose properties of Clostridium thermocellum were started to determine if the cellulose degradation end products can be enhanced for glucose (with a subsequent decrease in cellobiose). Implications of preliminary studies indicate that the cells or the enzyme(s) responsible for converting cellobiose to glucose can be manipulated environmentally and genetically to increase the final yield of glucose. The second area of effort is to the production of chemical feedstocks. Three fermentations have been identified for exploration. Preliminary reports on acrylic acid acetone/butanol, and acetic acid production by C. propionicum, C. acetobutylicum, and C. thermoaceticum, respectively, are included. (DMC)
Date: August 1, 1978
Creator: Wang, D.I.C.; Cooney, C.L.; Demain, A.L.; Gomez, R.F. & Sinskey, A.J.
Partner: UNT Libraries Government Documents Department

Degradation of cellulosic biomass and its subsequent utilization for the production of chemical feedstocks. Progress report, June 1, 1977--August 31, 1977

Description: Studies on the microbial degradation of cellulose biomass continues to be centered around Clostridium thermocellum. The effect of surfactants on growth and cellulase production by C. thermocellum was investigated. The effect of pH on growth and reducing sugar accumulation rate of Clostridium thermocellum on solka floc was evaluated. Activity of extracellular cellulase of Clostridium thermocellum ATCC 27405 was examined using TNP--CMC and Avicel as substrates. The pH optima are 5 and 4.5, respectively. Hydrolysis of either substrate is not inhibited by cellobiose, xylose, or glucose. The enzyme appears to be quite stable under reaction conditions at 60/sup 0/C. Thus far, regulation studies indicate that CMCase formation is not repressed by cellobiose. The search for plasmids in C. thermocellum was continued. The presence of plasmids was confirmed by cesium chloride ethidium bromide gradient centrifugation and electron microscopy. Two plasmids were detected, one with an approximate molecular weight of 1 x 10/sup 6/ daltons. Studies on the fermentation of lactic acid to propionic acid showed the pathway in C. propionicum to be simpler than in M. elsdenii and hence more amenable to manipulation for acrylate production. Using Lactobacillius delbrueckii, it was possible to convert glucose, cellobiose, and cellulose hydrolysates to lactic acid rapidly and quantitatively. Fermentations of C. acetobutylicum growing in soluble media were performed. Detailed studies of Clostridium thermoaceticum have shown that pH is the primary limiting factor in the production of acetic acid. pH-controlled fermentations indicated accumulations of over 30 gm/l of acetic acid.
Date: September 1, 1977
Creator: Wang, D.I.C.; Cooney, C.L.; Demain, A.L.; Gomez, R.F. & Sinskey, A.J.
Partner: UNT Libraries Government Documents Department

Degradation of cellulosic biomass and its subsequent utilization for the production of chemical feedstocks. Progress report, December 1, 1978-February 28, 1979

Description: The ongoing progress of a coordinated research program aimed at optimizing the biodegradation of cellulosic biomass to ethanol and chemical feedstocks is summarized. Growth requirements and genetic manipulations of clostridium thermocellum for selection of high cellulose producers are reported. The enzymatic activity of the cellulase produced by these organisms was studied. The soluble sugars produced from hydrolysis were analyzed. Increasing the tolerance of C. thermocellum to ethanol during liquid fuel production, increasing the rate of product formation, and directing the catabolism to selectively achieve high ethanol concentrations with respect to other products were studied. Alternative substrates for C. thermocellum were evaluated. Studies on the utilization of xylose were performed. Single stage fermentation of cellulose using mixed cultures of C. thermocellum and C. thermosaccharolyticum were studied. The study of the production of chemical feedstocks focused on acrylic acid, acetone/butanol, acetic acid, and lactic acid.
Date: February 1, 1979
Creator: Wang, D.I.C.; Cooney, C.L.; Demain, A.L.; Gomez, R.F. & Sinskey, A.J.
Partner: UNT Libraries Government Documents Department

Degradation of cellulosic biomass and its subsequent utilization for the production of chemical feedstocks. Progress report, September 1-November 30, 1978

Description: Studies on the accumulation of glucose during the fermentation of cellulose by Clostridium thermocellum are discussed. Production of ethanol and its relationship to growth rate in C. thermocellum is reported. Different biomasses were tested for ethanol yields. These included exploded poplar, sugar cane, bagasse, corn cobs, sweet gum, rice straw, and wheat straw. Thermophilic bacteria were tested to determine relationship of temperature to yield of ethanol. A preliminary report on isolating plaque forming emits derived from C. thermocellum is presented as well as the utilization of carbohydrates in nutrition. A cellulose enzyme is being purified from C. thermocellum. The production of chemical feedstocks by fermentation is reported. Acrylic acid, acetone/butanol, and acetic acid, produced by C. propionicum, C. acetobutylicum, and C. thermoaceticum, are discussed. (DC)
Date: November 1, 1978
Creator: Wang, D.I.; Cooney, C.L.; Demain, A.L.; Gomez, R.F. & Sinskey, A.J.
Partner: UNT Libraries Government Documents Department

Radioisotope and Radiation Applications. Quarterly Progress Report

Description: An evaluation was given of the possible hazards to consumers from radioisotope residues in consumer products. A laboratory demonstration was given of the use of Mn/sup 54/ to facilitate removal of manganese from process feed water. lt was found in the hazards evaluation that the "worst case" of radiation exposure from residual radioisotopes in steel gives a radiation exposure somewhat less than the maximum allowable dose levels for occupational exposure. Initial study indicates that for actual cases, the radiation exposures to be expected from radioisotope residues in steel products would ordinarily be small compared to natural background. An exception to this generalization might be found when a longer lived isotope like Mn/sup 54/ was present. Preliminary results of the laboratory demonstnation of using Mn/sup 54/ to monitor the removal of manganese from feed water indicated that the method may allow a considerable improvement in accuracy of process control. The study of the mechanism of formation of free radicals in polymeric materials was continued. Emphasis was placed on examination of the effect of structural factors on the efficiency of free-radical site formation in acrylate polymers. The investigation was extended to include an examination of the effect on free-radical formation of the constituents on the carbon atom located alpha to the ester group. Polymethylacrylate, polymethylmethacrylate, and polymethyl- alpha -chloroacrylate were used in this study. Measurement of the volatile products from the irradiation of the polymethyl- alpha -chloroacrylate was completed. The data substantiated earlier findings which indicated that the point of attack in free-radical formation occurs on the ester side chain. (auth)
Date: January 18, 1961
Creator: Sunderman, D. N.
Partner: UNT Libraries Government Documents Department

THE EFFECT OF RADIATION ON THE MECHANICAL PROPERTIES OF POLYMERS. A BIBLIOGRAPHY OF THE UNCLASSIFIED LITERATURE, 1955-SEPTEMBER 1962

Description: A bibliography of approximates 440 references is presented which is arranged into sections dealing with polyacrylates, polyamides, polybutadienes and copolymers, polycarbonates, cellulosics, epoxy resins, polyesters, polyethers, polyethylenes, natural rubber, neoprene, phenolics, polypropylene, rubbers, silicones, polystyrenes, urethanes, polyvinylidenes, polyvinyls, and miscellaneous systems. Reviews, data compilations, books, and references dealing with dynamic mechanical properties are also listed. (D.L.C.)
Date: July 1, 1963
Partner: UNT Libraries Government Documents Department

Diosmacycloalkanes as models for the formation of hydrocarbons from surface methylenes

Description: We are making progress on our investigation of the mechanism of olefin exchange with Os{sub 2}(C{sub 2}H{sub 4})(CO){sub 8}. We are probing this system by kinetic study of the reaction of Os{sub 2}(C{sub 2}H{sub 4})(CO){sub 8} with butyl acrylate (BA) under various pressures of ethylene.
Date: May 1, 1992
Creator: Norton, J.R.
Partner: UNT Libraries Government Documents Department

Investigation of test methods, material properties, and processes for solar cell encapsulants. Seventh annual report

Description: The goal of the program is to identify and evaluate encapsulation materials and processes for the protection of silicon solar cells for service in a terrestrial environment. Aging and degradation studies were performed including: thermal aging, sunlamp exposures, aging in controlled environment reactors and outdoor photothermal aging devices, and metal catalyzed degradation. Other tests addressed water absorption, primers and adhesives, soiling experiments, and corrosion protection. (LEW)
Date: January 1, 1983
Creator: Willis, P.B.
Partner: UNT Libraries Government Documents Department

Solar-collector materials exposure to the IPH site environment. Final report

Description: In-situ environmental exposure tests were conducted at nine proposed intermediate-temperature Industrial Process Heat (IPH) sites. Three types of reflector materials were evaluated for survivability at the nine sites: second-surface silvered glass, aluminized acrylic FEK-244 film on aluminum substrate, and Alzak (electropolished aluminum) on aluminum substrate. Black chrome absorber material and low-iron float glass were evaluated for thermal, photochemical, and environmental degradation. The reflector specimens were monitored for decreases in specular and hemispherical reflectance due to soil buildup. The absorber material was evaluated for changes in solar absorptivity and emissivity, and the float glass was monitored for changes in transmissivity. Surface and subsurface defects on all materials were examined microscopically and, where deemed of note, were documented photographically.
Date: January 1, 1982
Creator: Morris, V.L.
Partner: UNT Libraries Government Documents Department

Solar-collector-materials exposure to the IPH site environment. Volume 1. Final report

Description: In-situ environmental exposure tests were conducted at nine proposed intermediate-temperature Industrial Process Heat (IPH) sites. Three types of reflector materials were evaluated for survivability at the nine sites: second-surface silvered glass, aluminized acrylic FEK-244 film on aluminumsubstrate and Alzak (electropolished aluminum) on aluminium substrate. Black chrome absorber material and low-iron float glass were evaluated for thermal, photochemical, and environmental degradation. The reflector specimens were monitored for decreases in specular and hemispherical reflectance due to soil buildup. The absorber material was evaluated for changes in solar absorptivity and emissivity, and the float glass was monitored for changes in transmissivity. Surface and subsurface defects on all materials were examined microscopically and, where deemed of note, were documented photographically.
Date: January 1, 1982
Creator: Morris, V.L.
Partner: UNT Libraries Government Documents Department

Fever--A One-Dimensional Few-Group Depletion Program for Reactor Analysis

Description: The one-dimensional difiusion-theory depletion program FEVER, written in FORTRAN-II for a 32,000-word computer is described. The code allows for the representation of self-shielded burnable poisons and provides methods for automatically adjusting control poisons in various regions of the reactor according to some specified sequence. No intermediate tape manipulation is required during the calculations, since all program and data storage are contained in the fast memory of the computer. Information oriented to meet the needs of the potential user of the program and a documentation of the programming details. are presented. (auth)
Date: November 28, 1962
Creator: Todt, F.
Partner: UNT Libraries Government Documents Department

Degradation of cellulosic biomass and its subsequent utilization for the production of chemical feedstocks. Progress report, December 1, 1976--February 28, 1977

Description: The microbial degradation of cellulosic biomass has focused on the use of a thermophilic (55 to 60/sup 0/C), anaerobic microorganism, Clostridium thermocellum. When this organism is grown with a crystalline cellulose, the cellulases produced are mainly extracellular. This same organism when grown on solka floc, high specific growth rates are exhibited as well as the ability to produce high concentrations of soluble reducing sugars. The rate of soluble sugar production appears to be growth associated. Studies on acrylic acid production are focused on two organisms: Peptostreptococcus elsdenii and Clostridium propionicum. An economic analysis on the acetone/butanol fermentation has been completed. The results show that continuous operation can reduce significantly the production cost compared to batch operation with the cost of raw material being major fractions for both processes. An increase in solvent concentration will effect substantial cost reduction. The production of acetic acid by Clostridium thermoaceticum has been shown to occur rapidly by this organism. Acetic acid concentration between 15 to 20 gm/liter have been achieved, corresponding to 86 percent of the theoretical maximum yield.
Date: May 1, 1977
Creator: Wang, D. I. C.; Cooney, C. L.; Demain, A. L.; Gomez, R. F. & Sinskey, A. J.
Partner: UNT Libraries Government Documents Department