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A Review of the Utilization of Fission Fragment Energy for the Fixation of Nitrogen

Description: Report issued by the Brookhaven National Laboratory discussing methods of nitrogen fixation, and their economic impacts. As stated in the introduction, "studies are described on circulating dust fuels, as well as fixed plated, porous bed, and other types of fuels as the basis for chemo-nuclear reactor designs, and the various fuel systems are compared on a technical and economic basis" (p. 3). This report includes tables, and illustrations.
Date: January 17, 1961
Creator: Steinberg, Meyer; Powell, J. R. & Green, Leon
Partner: UNT Libraries Government Documents Department

Ultramicro Methods in Biochemistry: [Part] 7. The Determination of Plasma or Serum Urea Nitrogen, [Part] 8. The Determination of Serum Uric Acid, [Part] 9. The Determination of Serum Creatinine

Description: From Introduction: "This report describes the development of an ultramicro modification of the method of Chaney and Marbach which is reliable and remarkably suited to routine analysis in bulk."
Date: April 1965
Creator: Van Stewart, E. & Longwell, Bernard B.
Partner: UNT Libraries Government Documents Department

Kinetic Investigation of the Gas Phase Atomic Sulfur and Nitrogen Dioxide Reaction

Description: The kinetics of the reaction of atomic sulfur and nitrogen dioxide have been investigated over the temperature range 298 to 650 K and pressures from 14 - 405 mbar using the laser flash photolysis - resonance fluorescence technique. The overall bimolecular rate expression k (T) = (1.88 ± 0.49) x10-11 exp-(4.14 ± 0.10 kJ mol-1)/RT cm3 molecule-1 s-1 is derived. Ab initio calculations were performed at the CCSD(T)/CBS level of theory and a potential energy surface has been derived. RRKM theory calculations were performed on the system. It is found that an initially formed SNO2 is vibrationally excited and the rate of collisional stabilization is slower than the rate of dissociation to SO + NO products by a factor of 100 - 1000, under the experimental conditions.
Date: May 2011
Creator: Thompson, Kristopher Michael
Partner: UNT Libraries

Obligately Thermophilic Nitrogen-Fixation in Some Soil Bacteria

Description: In the work presented here, it is claimed that bacteria have been isolated which are capable of growth at high temperatures utilizing molecular nitrogen as their sole nitrogen source. Soil bacteria were isolated which grew at 55 C in nitrogen-free media. They were found to be obligatory thermophiles in nitrogen-free media and facultative thermophiles in media containing organically bound nitrogen.
Date: August 1971
Creator: Milam, Mary
Partner: UNT Libraries

Nitrogen Derivatives of Naphthoquinone

Description: A series of nitrogen derivatives of 1,4-naphthoquinone, which are structurally similar to the compounds of Hall, has been prepared by this worker. In general, the amido groups are those of the long-chain, fatty acids, and it is believed they will have increased physiological activity. These compounds are to be tested for medicinal activity by Parke-Davis and Company.
Date: June 1953
Creator: Wood, Frank M.
Partner: UNT Libraries

Biological Nitrogen Fixation in Two Southwestern Reservoirs

Description: This investigation has determined the presence of biological nitrogen fixation in two reservoirs in the southwestern United States: Lake Arlington and Lake Ray Hubbard. Subsequent tests have gathered baseline data on the effects of various biological, chemical, and physical parameters on in situ nitrogen fixation in these reservoirs. Of specific importance is the relationship between nitrogen fixation arid occasional blooms of blue-green algae which produce such problems as testes and odors in these water-supply impoundments.
Date: August 1973
Creator: Lawley, Gary G.
Partner: UNT Libraries

Functional Assessment of the Medicago truncatula NIP/LATD Protein Demonstrates That It Is a High-Affinity Nitrate Transporter

Description: Article on the functional assessment of the Medicago truncatula NIP/LATD protein demonstrating that it is a high-affinity nitrate transporter.
Date: October 2012
Creator: Bagchi, Rammyani; Salehin, Mohammad; Adeyemo, O. Sarah; Salazar, Carolina; Shulaev, Vladimir; Sherrier, D. Janine et al.
Partner: UNT College of Arts and Sciences

General Hydrology and External Sources of Nutrients Affecting Pine Lake, King County, Washington

Description: Objectives: This report presents the findings of a study that was designed to determine (1) the general hydrologic conditions in the immediate vicinity of the lake, and (2) the loadings of inorganic nitrogen and phosphorus from selected external sources that affect the lake.
Date: 1983
Creator: Dion, N. P.; Sumioka, S. S. & Winter, T. C.
Partner: UNT Libraries Government Documents Department

Nitrogen Deposition: A Component of Global Change Analyses

Description: The global cycles of carbon and nitrogen are being perturbed by human activities that increase the transfer from large pools of nonreactive forms of the elements to reactive forms that are essential to the functioning of the terrestrial biosphere. The cycles are closely linked at all scales, and global change analyses must consider carbon and nitrogen cycles together. The increasing amount of nitrogen originating from fossil fuel combustion and deposited to terrestrial ecosystems as nitrogen oxides could increase the capacity of ecosystems to sequester carbon thereby removing some of the excess carbon dioxide from the atmosphere and slowing the development of greenhouse warming. Several global and ecosystem models have calculated the amount of carbon sequestration that can be attributed to nitrogen deposition based on assumptions about the allocation of nitrogen among ecosystem components with different carbon-nitrogen ratios. They support the premise that nitrogen deposition is responsible for a an increasing terrestrial carbon sink since industrialization began, but there are large uncertainties related to the continued capacity of ecosystems to retain exogenous nitrogen. Whether terrestrial ecosystems continue to sequester additional carbon will depend in part on their response to increasing atmospheric carbon dioxide concentrations, which is widely thought to be constrained by limited nitrogen availability. Ecosystem models generally support the conclusion that the responses of ecosystems to increasing concentrations of carbon dioxide will be larger, and the range of possible responses will be wider, in ecosystems with increased nitrogen inputs originating as atmospheric deposition.
Date: December 31, 1997
Creator: Norby, Richard J.
Partner: UNT Libraries Government Documents Department

Encapsulation of Protonated Diamines in a Water-Soluble Chiral, Supramolecular Assembly Allows for Measurement of Hydrogen-Bond Breaking Followed by Nitrogen Inversion/Rotation (NIR)

Description: Amine nitrogen inversion, difficult to observe in aqueous solution, is followed in a chiral, supramolecular host molecule with purely-rotational T-symmetry that reduces the local symmetry of encapsulated monoprotonated diamines and enables the observation and quantification of {Delta}G{double_dagger} for the combined hydrogen-bond breaking and nitrogen inversion rotation (NIR) process. Free energies of activation for the combined hydrogen-bond breaking and NIR process inside of the chiral assembly were determined by the NMR coalescence method. Activation parameters for ejection of the protonated amines from the assembly confirm that the NIR process responsible for the coalescence behavior occurs inside of the assembly rather than by a guest ejection/NIR/re-encapsulation mechanism. For one of the diamines, N,N,N{prime},N{prime}-tetramethylethylenediamine (TMEDA), the relative energy barriers for the hydrogen-bond breaking and NIR process were calculated at the G3(MP2)//B3LYP/6-31++G(d,p) level of theory, and these agreed well with the experimental data.
Date: September 19, 2007
Creator: Meux, Susan C.; Pluth, Michael D.; Bergman, Robert G. & Raymond, Kenneth N.
Partner: UNT Libraries Government Documents Department

REACTIONS OF MOLYBDENUM, TUNGSTEN AND URANIUM HEXAFLUORIDES WITH NITROGEN COMPOUNDS. III. NITROGEN DIOXIDE AND NITROGEN OXYHALIDES

Description: Reaction between gaseous nitrogen dioxide and gaseous uranium hexafluoride results in the formation of the nitrylium salt NO/sub 2/UF/sub 6/. Under similar conditions no reaction occurs between nitrogen dioxide and molybdenum and tungsten hexafluorides. Reaction between nitrosyl and nitryl fluorides and the three hexafluorides results in solid compounds of the composition NO/sub x/F x MF/sub 6/, where x is 1 or 2 and M represents Mo, W, or U. Reaction between gaseous or liquid nitrosyl chloride and molybdenum and uranium hexafluorides results in the formation of the nitrosylium salts NOMoF/sub 6/ and NOUF/sub 6/ and chlorine. Tungsten hexafluoride was found not to react with nitrosyl chloride. The conditions and stoichiometry of the reactions are described. The nitrylium salt, NO/sub 2/UF/sub 6/, is characterized, and some of its physical and chemical properties are described. The NO/sub x/F x MF/sub 6/ compounds are characterized, and some physical properties are described. Evidence for the presence of NO/sup +/ and MF/sup -//sub 7/ ions in these compounds is given. The nitrosylium salts, NOMoF/sub 6/ and NOUF/sub 6/, were characterized previously. (auth)
Date: January 27, 1961
Creator: Geichman, J.R.; Ogle, P.R. & Swaney, L.R.
Partner: UNT Libraries Government Documents Department

Carbon 14 from Lead Nitrate

Description: Report describing the production of carbon 14 from Pb(NO3)2 in the Oak Ridge Nuclear Reactor via the reaction N14 (n.p.) C14.
Date: 1949
Creator: Goodman, Martin R. & Longacre, Andrew, 1904-
Partner: UNT Libraries Government Documents Department

Plasma-assisted catalytic reduction of NO<sub>x</sub>

Description: Many studies suggest that lean-NO<sub>x</sub> SCR proceeds via oxidation of NO to NO¬ by oxygen, followed by the reaction of the NO¬ with hydrocarbons. On catalysts that are not very effective in catalyzing the equilibration of NO+O¬ and NO¬, the rate of N¬ formation is substantially higher when the input NO<sub>x</sub> is NO¬ instead of NO. The apparent bifunctional mechanism in the SCR of NO<sub>x</sub> has prompted the use of mechanically mixed catalyst components, in which one component is used to accelerate the oxidation of NO to NO¬, and another component catalyzes the reaction between NO¬ and the hydrocarbon. Catalysts that previously were regarded as inactive for NO<sub>x</sub> reduction could therefore become efficient when mixed with an oxidation catalyst. Preconverting NO to NO¬ opens the opportunity for a wider range of SCR catalysts and perhaps improves the durability of these catalysts. This paper describes the use of a non-thermal plasma as an efficient means for selective partial oxidation of NO to NO¬. When combined with some types of SCR catalyst, the plasma can greatly enhance the NO<sub>x</sub> reduction and eliminate some of the deficiencies encountered in an entirely catalyst-based approach. efficiency for reduction of NO<sub>x</su
Date: August 24, 1998
Creator: Voss, K; Brusasco, R M; Kung, H H; Kung, M C; Merritt, B T; Penetrante, B M et al.
Partner: UNT Libraries Government Documents Department