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in subjects: "Carbonic Acid"

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Susceptibility of Granite Rock to scCO2/Water at 200 degrees C and 250 degrees C

Granite rock comprising anorthoclase-type albite and quartz as its major phases and biotite mica as the minor one was exposed to supercritical carbon dioxide (scCO{sub 2})/water at 250 C and 13.78 MPa pressure for 104 hours. For comparison purpose, four other rocks, albite, hornblende, diorite, and quartz, also were exposed. During the exposure of granite, ionic carbonic acid, known as the wet carbonation reactant, preferentially reacted with anorthoclase-type albite and biotite, rather than wi… more

Date: January 1, 2011

Creator: Sugama, T. & Gill, S., Ecker, L., Butcher, T., Warren, J.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Accelerated Carbonate Dissolution as a CO2 Separation and Sequestration Strategy

We have proposed a technique that could reduce CO{sub 2} emissions from near coastal fossil-fuel power plants using existing power plant cooling water flow rates (Rau and Caldeira, 1999; Caldeira and Rau, 2000). Preliminary cost estimates are as low as $68 per tonne C sequestered, as compared to > $170 per tonne C estimated for other approaches to CO{sub 2} separation with geologic or deep-ocean storage. Engineers at McDermott Technologies, Inc., have independently estimated the cost of our … more

Date: February 18, 2004

Creator: Caldeira, K G; Knauss, K G & Rau, G H

Item Type: Report

Partner: UNT Libraries Government Documents Department

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CO2 storage in solid form: a study of direct mineral carbonation

Direct mineral carbonation by an ex-situ process in an aqueous system has been investigated over the past two years. The process utilizes a slurry of water mixed with a magnesium silicate mineral, such as olivine [forsterite end member (Mg2SiO4)], or serpentine [Mg3Si2O5(OH)4]. This slurry is reacted with sub- or supercritical carbon dioxide (CO2) to produce magnesite (MgCO3). The CO2 is dissolved in water to form carbonic acid (H2CO3), which dissociates to H+ and HCO3-. The H+ ion hydrolyzes t… more

Date: January 1, 2000

Creator: O'Connor, William K.; Dahlin, David C.; Nilsen, David N.; Rush, G.E.; Walters, Richard P. & Turner, Paul C.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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In situ Raman spectroscopy of lithium electrode surface in ambient temperature lithium secondary battery. Final report

Raman spectroscopy was used to characterize surface layers on lithium electrodes in different solvents such as propylene carbonate (PC), dimethyl carbonate (DMC), diethyl carbonate (DEC), and polyethylene glycol 400 dimethyl ether (PEG400DME). Both DMC and DEC were used singly, and also mixed with either methyl acetate (MA) or methyl formate (MF). The Raman spectra showed that passive films formed on the Li surface in different solvents may have different chemical structures, which changed duri… more

Date: September 1, 1992

Creator: Tachikawa, Hiroyasu

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Preparation of urethane adhesives. Final report

The scale-up and production of two urethane prepolymers were investigated. The prepolymers can be used as adhesives which have potential use as a replacement for the Adiprene L-100/MOCA system (E. I. du Pont de Nemours and Company). One prepolymer is based on the reaction of a polytetramethylene ether glycol (PTMEG) with 4,4'-methylenebis(phenylisocyanate) (MDI) and in the other the PTMEG is reacted with 4,4'-methylenebis(cyclohexylisocyanate) (H/sub 12/MDI). The scale-up from the lab… more

Date: September 1, 1976

Creator: Parker, B. G.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Carbon dioxide sequestration by ex-situ mineral carbonation

The process developed for carbon dioxide sequestration utilizes a slurry of water mixed with olivine- forsterite end member (Mg{sub 2}SiO{sub 4}), which is reacted with supercritical CO{sub 2} to produce magnesite (MgCO{sub 3}). Carbon dioxide is dissolved in water to form carbonic acid, which likely dissociates to H{sup +} and HCO{sub 3}{sup -}. The H{sup +} hydrolyzes the silicate mineral, freeing the cation (Mg{sup 2+}), which reacts with the HCO{sub 3}{sup -} to form the solid carbonate. Re… more

Date: January 1, 2000

Creator: O'Connor, W. K.; Dahlin, D. C.; Turner, P. C. & Walters, R.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Test methods for the dynamic mechanical properties of polymeric materials. Final report

Various test geometries and procedures for the dynamic mechanical analysis of polymers employing a mechanical spectrometer have been evaluated. The methods and materials included in this work are forced torsional pendulum testing of Kevlar/epoxy laminates and rigid urethane foams, oscillatory parallel plate testing to determine the kinetics of the cure of VCE with Hylene MP, oscillatory compressive testing of B-3223 cellular silicone, and oscillatory tensile testing of Silastic E and single Kev… more

Date: June 1, 1980

Creator: Baker, G.K.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Bond strength of urethane and epoxy-modified adhesives

A number of urethane and epoxy-modified urethane systems were evaluated as room-temperature-curing adhesives. The systems were formulated to yield a variety of modulus levels and to be compatible with certain chemically sensitive materials.

Date: April 26, 1976

Creator: Childress, F. G.; Zava, A. K. & Miller, C. E.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Effective Permeability Change in Wellbore Cement with Carbon Dioxide Reaction

Portland cement, a common sealing material for wellbores for geological carbon sequestration was reacted with CO{sub 2} in supercritical, gaseous, and aqueous phases at various pressure and temperature conditions to simulate cement-CO{sub 2} reaction along the wellbore from carbon injection depth to the near-surface. Hydrated Portland cement columns (14 mm diameter x 90 mm length; water-to-cement ratio = 0.33) including additives such as steel coupons and Wallula basalt fragments were reacted w… more

Date: November 1, 2011

Creator: Um, Wooyong; Jung, Hun Bok; Martin, Paul F. & McGrail, B. Peter

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

High load bearing flexible urethane foams

The load bearing properties of flexible urethane foam as a function of the formulation variables were investigated. Varying levels of a polystyrene-acrylonitrile-polyol were added to the foam systems to increase the load-bearing capabilities of the resultant materials. The formulation water level and fluorocarbon blowing agent level were also varied to provide flexible urethane foams covering a wide range of density and compressive properties. The compression set/compression deflection properti… more

Date: November 1, 1977

Creator: Parker, B. G.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Quantitative comparison of electronic component/solder joint stress relief in encapsulated assemblies

A quantitative comparison was made of various stress relief bends with and without sleeving in three commonly used encapsulants. Silicone rubber and heat shrinkable polyolifin sleeving were used on right angle, full loop, and hump style lead bends. Small (from 254 ..mu..m to 762 ..mu..m diameter) and large (762 ..mu..m to 1.27 mm diameter) wires were used to simulate small and large component leads. The component leads were encapsulated in microballoon-filled epoxy, 128 kg/m/sup 3/ urethane foa… more

Date: January 1, 1979

Creator: Cummings, D.A.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Material and processing comparisons of four conformal coatings. Final report

This evaluation compares the processing and properties of four materials in common use as conformal coatings. The processes were optimized to obtain the highest level of electrical properties and direct comparisons of physical properties at three temperatures are included. A design manual, BDX-613-1216, was developed as part of this effort.

Date: March 1, 1977

Creator: Caruthers, D. J.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Modelling regulation of decomposition and related root/mycorrhizal processes in arctic tundra soils

Since this was the final year of this project principal activities were directed towards either collecting data needed to complete existing incomplete data sets or writing manuscripts. Data sets on Imnaviat Creek watershed basin are functionally complete and data finialized on the cellulose mineralizaiton and dust impact on soil organic carbon and phsophorus decomposition. Seven manuscripts were prepared, and are briefly outlined.

Date: January 1, 1992

Creator: Linkins, A. E.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Carbon dioxide sequestration by direct mineral carbonation with carbonic acid

The Albany Research Center (ARC) of the U.S. Dept. of Energy (DOE) has been conducting a series of mineral carbonation tests at its Albany, Oregon, facility over the past 2 years as part of a Mineral Carbonation Study Program within the DOE. Other participants in this Program include the Los Alamos National Laboratory, Arizona State University, Science Applications International Corporation, and the DOE National Energy Technology Laboratory. The ARC tests have focused on ex-situ mineral carbona… more

Date: January 1, 2000

Creator: O'Connor, William K.; Dahlin, David C.; Nilsen, David N.; Walters, Richard P. & Turner, Paul C.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Problems associated with the use of urea-formaldehyde foam for residential insulation. Part I. The effects of temperature and humidity on formaldehyde release from urea-formaldehyde foam insulation

The study is concerned primarily with those properties related to formaldehyde and its application as an ingredient in urea-formaldehyde resins. In particular the effects of temperature and humidity on urea-formaldehyde foam are discussed.

Date: September 1, 1979

Creator: Long, K.R.; Pierson, D.A.; Brennan, S.T.; Frank, C.W. & Hahne, R.A.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Boron trichloride purification with a KrF excimer laser

Selective ultraviolet photolysis using a KrF excimer laser has been used to substantially reduce the phosgene impurity in a binary mixture of boron trichloride and phosgene. Infrared spectroscopic analysis of the sample before and after irradiation shows that it is possible to highly purify commercially available boron trichloride with this technique.

Date: January 1, 1980

Creator: Hyer, R.C.; Hartford, A. Jr. & Atencio, J.H.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Peak-power dependence of rovibronic populations below the quasicontinuum during IR multiphoton absorption

Experimental studies on IR multiphoton absorption and dissociation have generally provided insight only into the relationship of IR laser characteristics such as power, wavelength, and mode structure to the observables dissociation yields, average number of photons absorbed, and product energy distribution. As a result, theoretical modeling of absorption at levels below the quasicontinuum has been based on facts somewhat removed from the actual phenomenon of interest. The experiments presented … more

Date: January 1, 1981

Creator: Brenner, D M

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Effects of pesticides on crab cheliped regeneration

The mud crab cheliped regeneration bioassay has proven to be a sensitive and reliable bioassay in studies of the potential sublethal effects of pesticides, including teratogenesis, spontaneous autotomy, and duration of the various stages of development. The assay has also been demonstated to be a useful indication of mortality associated with the impact of these chemicals of anthropogenic origin during the megalopal and early postlarval stages of development. Four pesticides were tested here us… more

Date: January 1, 1993

Creator: Costlow, J.D. Jr.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Effect of hydrotropic salts on phase relationships involving hydrocarbons, water, and alcohols

Hydrotropic salts, which can increase the solubility of organic materials in aqueous solutions, are useful to tertiary oil recovery. We have examined effects on solubility of hydrocarbons in water (with and without alcohols) through addition of inorganic hydrotropic salts, such as perchlorates, thiocyanates, and iodides - high in the usual Hofmeister series - and of organic salts such as short chain alkyl benzene sulfonates and other salts based on substituted benzene derivatives. Although the … more

Date: January 1, 1980

Creator: Ho, P.C. & Kraus, K.A.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Preliminary evaluation of the biological oxidation of thiocyanates. Progress report, November 30, 1977--February 28, 1978

Acclimated biological cultures were developed from activated sludge taken from coke plant biological waste treatment facilities. These cultures are capable of degrading potassium thiocyanate from an original concentration of 2000 mg/l SCN to less than 1 mg/l in an aeration period of 9 hours. pH inhibition appears to be significant at values greater than 7.6. Substrate inhibition occurs at concentrations of thiocyanate greater than 500 mg/l. Air stripping of thiocyanate does not appear to occur … more

Date: March 1, 1978

Creator: Neufeld, R.D. & Valiknac, T.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Sensitive, coupled assay for plasminogen activator using a thiol ester substrate for plasmin

Several assays for plasminogen activator employ a direct assay method. These are remarkably sensitive methods, yet they suffer in comparison to the sensitivity of coupled methods. Coupling the assay with plasminogen not only amplifies the sensitivity by the multiplicative effect of plasmin, but insures that only those proteases specific for plasminogen are assayed. The choice of substrate for plasmin is critical. A thiol ester substrate, thiobenzyl benzyloxy-carbonyl-L-lysinate (Z-Lys-SBzl), ha… more

Date: January 1, 1980

Creator: Coleman, P L & Green, G D.J.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Physicochemical Studies of the Carbamate-CO/sub 2/-Solvent System

The formation of carbamate from CO/sub 2/ and the various amine solutions has been investigated for the purpose of elucidating the structure of the species generated in the reaction. The amine solutions used were 1 and 2 molar solutions of di-n-butylamine (DNBA) in triethylamine (TEA), pure DNBA and pure TEA. It has been found that the nonaqueous solvent participates in the formation of carbamate in 1 and 2M-DNBA/TEA solutions as a proton acceptor in DNBA-carbamate formation. However, due to th… more

Date: August 1, 1977

Creator: Prencipe, M. & Ishida, T.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Effect of fluoride, chloride, bromide, and thiocynate on potentiometric titrations of iron(II)-tin(II) mixtures with cerium(IV)

A two-step curve is expected in the potentiometric titration of Fe(II)-Sn(II) mixtures with Ce(IV) in H/sub 2/SO/sub 4/. Each end point should indicate the respective oxidation of Sn(II) and Fe(II). However, experimentally only one end point was found; it corresponded to the total oxidation of Sn(II) and Fe(II). When this oxidation-reduction reaction was carried out in the presence of Cl/sup -/, the theoretical behavior was observed. The present study was done to ascertain if monovalent anions … more

Date: July 31, 1980

Creator: Kwok, Y.M.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Molecular models for explosives: Application to NTO (3-nitro-1,2,4-triazol-5-one)

We calculated structures and energies for several isomers of 3-nitro-1,2,4-triazol-5-one (NTO), using molecular orbital theory. The 1H,4H isomer was found to be lowest in energy. We predict the existence of an additional low-lying form that may either be directly observable or have its existence inferred in experiments. We also calculated some possible forms of the conjugate base of NTO. Finally, we have applied a new method of calculation to predict the geometry of the diaminoguanidinium salt … more

Date: January 1, 1989

Creator: Ritchie, J. P. & Kober, E. M.

Item Type: Article

Partner: UNT Libraries Government Documents Department