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The Radical Pair Yield of Ionizing Radiation in Ferrous Sulfate and Ceric Sulfate Solutions

Description: The radical pair yield from dilute aqueous solutions of ferrous sulfate and ceric sulfate solutions has been determined. Using the mechanism of Weiss et al. for the hydrogen formation in deaerated solutions of ferrous sulfate it is found that 23% of the radicals recombine to yield stable products in good agreement with values obtained by others. Two results are found for the reduction of ceric sulfate solutions, depending on the wave length of X-rays used. This indicates that the mechanism post… more
Date: unknown
Creator: Johnson, Everett, R.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Dissociation of fast molecular-ion beams in thin foils. [1 MeV/nucleon]

Description: Distributions in angle and in energy were measured for the break-up fragments produced when fast (approximately MeV/nucleon) beams of molecular ions (H/sub 2//sup +/, HeH/sup +/, OH/sup +/, etc.) bombard thin foil targets. Studies were made using both amorphous and crystalline targets. The results display some dramatic departures from expectations based on a simple Coulomb explosion picture in which a cluster of nuclei stripped of their binding electrons move apart under the influence of their … more
Date: January 1, 1976
Creator: Gemmell, D. S.; Vager, Z. & Zabransky, B. J.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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HALTHANE polyol round robin test results

Description: A round robin chemical analysis of two halthane adhesive polyol cure agents for hydroxyl number, acid number, and water content has been conducted between analytical laboratories at LLL, Pantex, Bendix, and Union Carbide (Y-12). The reported data show sufficient scatter as to recommend that specific test procedures be called out. Different methods were used in the various labs, some with slight modifications, others were entirely different. Also, some ASTM procedures were misapplied and others … more
Date: August 19, 1976
Creator: Larsen, Fred N.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Large Scale Atmospheric Chemistry Simulations for 2001: An Analysis of Ozone and Other Species in Central Arizona

Description: A key atmospheric gas is ozone. Ozone in the stratosphere is beneficial to the biosphere because it absorbs a significant fraction of the sun's shorter wavelength ultraviolet radiation. Ozone in the troposphere is a pollutant (respiratory irritant in humans and acts to damage crops, vegetation, and many materials). It affects the Earths energy balance by absorbing both incoming solar radiation and outgoing long wave radiation. An important part of the oxidizing capacity of the atmosphere involv… more
Date: October 8, 2002
Creator: Atherton, C; Bergmann, D; Cameron-Smith, P; Connell, P; Molenkamp, C; Rotman, D et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Measurement of HO{sub x}{center_dot} production rate due to radon decay in air

Description: Radon in indoor air may cause the exposure of the public to excessive radioactivity. Radiolysis of water vapor in indoor air due to radon decay could produce ({center_dot}OH and HO{sub 2} {center_dot}) that may convert atmospheric constituents to compounds of lower vapor pressure. These lower vapor pressure compounds might then nucleate to form new particles in the indoor atmosphere. Chemical amplification was used to determine HO{sub x}{center_dot} production rate in indoor air caused by radon… more
Date: August 1, 1993
Creator: Ding, Huiling
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries Government Documents Department
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Fundamental limitations of non-thermal plasma processing for internal combustion engine NO{sub x} control

Description: This paper discusses the physics and chemistry of non-thermal plasma processing for post-combustion NO{sub x} control in internal combustion engines. A comparison of electron beam and electrical discharge processing is made regarding their power consumption, radical production, NO{sub x} removal mechanisms, and by product formation. Can non-thermal deNO{sub x} operate efficiently without additives or catalysts? How much electrical power does it cost to operate? What are the by-products of the p… more
Date: August 19, 1993
Creator: Penetrante, B. M.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Global emissions and models of photochemically active compounds

Description: Anthropogenic emissions from industrial activity, fossil fuel combustion, and biomass burning are now known to be large enough (relative to natural sources) to perturb the chemistry of vast regions of the troposphere. A goal of the IGAC Global Emissions Inventory Activity (GEIA) is to provide authoritative and reliable emissions inventories on a 1{degree} {times} 1{degree} grid. When combined with atmospheric photochemical models, these high quality emissions inventories may be used to predict … more
Date: May 20, 1993
Creator: Penner, J. E.; Atherton, C. S. & Graedel, T. E.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Combustion Research Program: Flame studies, laser diagnostics, and chemical kinetics. Final report, 15 July 1987--15 June 1992

Description: This project has comprised laser flame diagnostic experiments, chemical kinetics measurements, and low pressure flame studies. Collisional quenching has been investigated for several systems: the OH radical, by H{sub 2}0 in low pressure flames; the rotational level dependence for NH, including measurements to J=24; and of NH{sub 2} at room temperature. Transition probability measurements for bands involving v{prime} = 2 and 3 of the A-X system of OH were measured in a flame. Laser-induced fluor… more
Date: September 1, 1992
Creator: Crosley, D. R.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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On the formation of iron(III) oxides via oxidation of iron(II)

Description: Formation of iron oxides in aqueous salt solutions is reviewed. The discussion is focused on the oxidation of iron(II) and the following hydrolysis process that leads to the formation of a solid phase from homogeneous solutions. Results from our own studies on the kinetics of the oxidation reactions and the ensuing growth processes are presented.
Date: September 1, 1994
Creator: Bongiovanni, R.; Pelizzetti, E.; Borgarello, E. & Meisel, D.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Incineration alternatives for combustible waste ultraviolet/hydrogen peroxide process. Annual report, FY 1992

Description: We have demonstrated that the ultraviolet light/hydrogen peroxide (UV/H{sub 2}O{sub 2} process is capable of completely destroying liquid and solid organic wastes. Using the UV/H{sub 2}O{sub 2} process, we destroyed two liquid wastes: ethylene glycol (water-soluble) and Trimsol (water-dispersible), and two solid wastes: sodium salts of carboxymethylcellulose (water-soluble) and powdered fibrous cellulose (water-insoluble cellulose). We have found that Fenton`s reagent is needed to treat fibrous… more
Date: March 1, 1993
Creator: Wang, F.; Cassidy, K. & Lum, B.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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DNA damage produced by exposure of supercoiled plasmid DNA to high- and low-LET ionizing radiation: Effects of hydroxyl radical quenchers. DNA breakage, neutrons, OH radicals

Description: A supercoiled plasmid of 7300 base pairs was isolated and exposed in an aqueous environment to {sup 60}Co {gamma} rays and JANUS 0.85 MeV fission-spectrum neutrons. Dose responses for the production of single-strand breaks (SSBs), double-strand breaks (DSBs) and alkali-labile sites (ALSs) were compared with computations made from the conversion of the supercoil to its relaxed and linear forms. The relative biological effectiveness (RBE) for production of SSBs and DSBs was similar to that previo… more
Date: August 1, 1994
Creator: Peak, J. G.; Ito, T.; Peak, M. J. & Robb, F. T.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Plasma-assisted cleanup of flue gas. [Quarterly] technical report, March 1, 1993--May 31, 1993

Description: The objective of the proposed research is to design and implement a novel scheme for the combined removal of SO{sub 2} and NO{sub x} using a dielectric-barrier discharge in conjunction with UV irradiation. This investigation requires the design of a dielectric-barrier reactor and testing the proposed scheme under different conditions. The testing of the uniformity of the discharge with UV irradiation has been very successful. The details are provide-din this report and has been submitted to the… more
Date: September 1, 1993
Creator: Dhali, S. K.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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[Reaction Dynamics of High-Temperature Systems]. Final Report

Description: Objective was to study reactions at superthermal collision energies using a fast neutral beam produced by photodetachment. Systems under initial study included basic oxygen-hydrogen reactions. Although progress was made on each stage of the experiment, conflicting requirements (maximizing photodetachment efficiency and maximizing transmission through reaction zone) precluded ultimate success. Parameters described refer to the model system O+H{sub 2}{r_arrow}OH+H. 2 figs.
Date: March 8, 1992
Creator: Graff, M. M.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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The relationship between hydroxyl groups on oxide surfaces and the properties of supported metals. Progress report, June 1, 1992--December 31, 1992

Description: Purpose of this investigation is to characterize the relation between the complex hydroxyl inventory at oxide/solution interface and the intrinsic acid/base properties of partially dehydroxylated oxides.
Date: December 31, 1992
Creator: Schwarz, J. A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Combustion Research Program: Flame studies, laser diagnostics, and chemical kinetics. Progress report, 15 July 1987--3 December 1990

Description: We have made a detailed study of the care that must be taken to correctly measure OH radical concentrations in flames. A large part of these studies has concerned collisional quenching of hydride radical species (OH, NH, and NH{sub 2}), in particular the dependence upon rotational level and collision velocity (temperature). The results on OH and NH have shown unique and interesting behavior from the viewpoint of fundamental molecular dynamics, pointing to quenching often governed by collisions … more
Date: January 22, 1991
Creator: Crosley, D. R.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Study of the atmospheric chemistry of radon progeny in laboratory and real indoor atmospheres. Progress report, May 1, 1993--January 31, 1994

Description: Progress is reported on the chemical and physical behavior of the {sup 218}Po atom immediately following its formation by the alpha decay of radon. Two areas of radon progeny behavior are being pursued; laboratory studies under controlled conditions to better understand the fundamental physical and chemical processes that affect the progeny`s atmospheric behavior and studies in actual indoor environments to develop a better assessment of the exposure of the occupants of that space to the size a… more
Date: January 1, 1993
Creator: Hopke, P. K.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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A shock tube study of the reactions of the hydroxyl radical with combustion species and pollutants. Progress report

Description: To extend the database of reliable high temperature measurements of OH radicals with hydrocarbons and other fuels and their decomposition products, we undertook, a research program with both experimental and computational tasks. The experimental goal was to design a procedure for measuring, at combustion temperatures, the reaction rate coefficients of OH radicals with fuels and other species of importance in combustion or propulsion systems. The computational effort was intended to refine the s… more
Date: August 1, 1992
Creator: Cohen, N.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Biologically important radiation damage in DNA. Annual progress report, May 1, 1993--January 31, 1994

Description: Most DNA damage by the hydroxyl radical is confined to the bases, and this base damage represents an important component of locally multiply demanded sites (LMOS). The yields of the major damaged bases have been determined by gas chromatography mass spectrometry. For our propose, it was necessary to convert a known fraction of these damaged bases to strand breaks and then assay these labile sites as the increase in strand break yield over the normally observed level. Three potential agents by w… more
Date: March 1, 1994
Creator: Ward, J. F.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Elementary reaction rate measurements at high temperatures by tunable-laser flash-absorption

Description: The major objective of this program is to measure thermal rate coefficients and branching ratios of elementary reactions. To perform these measurements, we have constructed an ultrahigh-purity shock tube to generate temperatures between 1000 and 5500 K. The tunable-laser flash-absorption technique is used to measure the rate of change of the concentration of species which absorb below 50,000 cm{sup {minus}1} e.g.: OH, CH, and CH{sub 3}. This technique is being extended into the vacuum-ultraviol… more
Date: March 20, 1992
Creator: Hessler, J. P.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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A shock tube study of the reactions of the hydroxyl radical with combustion species. Progress report, June 1990--May 1991

Description: The reactions of OH radicals with hydrocarbons have received a great deal of attention in recent years because of these processes are principal steps in the oxidation of organic fuels -- whether occurring in combustion/propulsion systems, in the atmosphere, or elsewhere. Of the various radicals capable of attacking hydrocarbons, OH radicals are generally the most reactive, and their reactions directly yield water molecules, one of the major final oxidation products. In the atmosphere, the combi… more
Date: May 21, 1991
Creator: Cohen, N.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Development of atmospheric characteristics of chlorine-free alternative fluorocarbons. Report on R-134a and E-143a

Description: Rate constants have been measured for the gas phase reaction of OH radicals with 1,1,1,2-tetrafluoroethane R-134a (CH{sub 2}F-CF{sub 3}) and methyl trifluoromethyl ether E-143a (CH{sub 3}-O-CF{sub 3}) over the temperature range 298--460 K. Arrhenius expressions were derived for atmospheric modeling. The infrared absorption cross-sections for R-134a and E-143a have been measured in the region from 400 to 1600 cm{sup {minus}1} and the integrated band strengths have been calculated. The atmospheri… more
Date: April 1, 1993
Creator: Orkin, V. L.; Khamaganov, V. G.; Guschin, A. G.; Kasimovskaya, E. E. & Larin, I. K.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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The effect of chemical reactivity on source reconciliation modeling of nonmethane hydrocarbons

Description: Source fingerprints for 18 nonmethane hydrocarbons (NMHCS) containing 2-8 carbon atoms are currently used to apportion NMHC sources by chemical mass balance (CMB) modeling approaches. The source profiles must be stable in the troposphere to obtain accurate CMB model predictions. The NMHC source apportionment compounds are susceptible to gas phase oxidation in the atmosphere by hydroxyl radical (OH). Expected tropospheric lifetimes for peak concentrations of OH in typical urban air range from an… more
Date: April 1, 1994
Creator: Doskey, P. V. & Gaffney, J. S.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Rate coefficient for the reaction H + O{sub 2} {yields} OH + O: Results from 2000 to 5300 K

Description: Tunable-laser flash-absorption has recently provided an unprecedented extension of the temperature range over which the rate of the reaction H + O{sub 2} {yields} OH + O has been measured, resolving an 18-year-old controversy over the high-temperature behavior of the rate of the most important reaction in combustion. Studies have shown that the rate of the above reaction follows a simple Arrhenius expression, k(T) = 1.62 {times} 10{sup {minus}10} exp[{minus}7474/T(K)] cm{sup 3} s{sup {minus}1},… more
Date: March 1, 1994
Creator: Hessler, J. P. & Du, Hong
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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