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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

Synthesis, scale-up, and characterization of 2,6-diamino-3,5-dinitropyrazine-1-oxide (LLM-105)

Description: We have synthesized 4OOg of the new, insensitive, energetic heterocycle, 2,6-diamino-3,5-dinitropyrazine-l-oxide (LLM-105) with 81% the energy of HMX and excellent thermal stability. The synthesis is a three step reaction sequence from the commercially available starting material, 2,6-dichloropyrazine, with an overall yield of 36%. In this paper we will describe the scale-up of the synthesis of LLM- 105 and report on performance and shock sensitivity experiments performed on this material.
Date: April 27, 1998
Creator: Pagoria, P. F.
Partner: UNT Libraries Government Documents Department

Quantum symmetry and photoreactivity of azabenzenes

Description: The fundamental processes associated with a photochemical reaction are described with reference to experimental properties of azabenzenes. Consideration of both excitation and relaxation processes led to presentation of the symmetry propagator, a unifying principle which maps system fluctuations (perturbations acting on an initial state) with dissipations (transitions to different states), thus directing the energy flow along competing reactive and nonreactive pathways. A coherent picture of relaxation processes including chemical reactions was constructed with the aid of spectroscopic data. Pyrazine (1,4 diazine) possesses vibronically active modes which provide an efficient mechanism for internal conversion to the first excited singlet state, where other promoting modes of the correct symmetry induce both intersystem crossing to the triplet manifold, isomerization through diaza-benzvalene, and chemical reactions through cycloreversion of dewar pyrazine to yield HCN plus an azete. At higher energies simple H atom loss and internal conversion become more predominant, leading to ring opening followed by elimination of methylene nitrile and ground state reaction products. Efficiency of chemical transformations as dissipation mechanisms versus competing fluorescence, phosphorescence and radiationless relaxation was mapped from near ultraviolet to far ultraviolet by photodissociation quantum yields into reaction channels characterized by molecular beam photofragment translational spectroscopy. A reaction path model for azabenzene photochemistry was presented and tested against experiment. Presence of undiscovered channels in other azabenzene systems was predicted and verified. The dominant process, HCN elimination, was resolved into three distinct channels. Both molecular and atomic hydrogen elimination was observed, the former with significant vibrational excitation. Small yields of isomerization products, acetylene and N2, were also observed.
Date: June 1995
Creator: Chesko, J. D. M.
Partner: UNT Libraries Government Documents Department

A diethyl phosphonate containing oxazoline: Synthesis and characterization of monomer and homopolymer

Description: A diethyl phosphonate oxazoline monomer and its polymer have been synthesized. The monomer appears to polymerize via a ring-opening mechanism giving the expected polyethyleneimine backbone with pendant carbonyl groups. Two distinct molecular weights were produced during polymerization suggesting two mechanisms of chain growth. Studies are underway to elucidate the reasons for this. This polymer has potential as a metal-chelating agent.
Date: May 1, 1995
Creator: Hermes, R.E.; Thompson, R.D. & Valdez, L.S.
Partner: UNT Libraries Government Documents Department

The MAP3S Aerosol Sulfate Acidity Network: A Progress Report and Data Summary, November 1981

Description: Abstract: A network of five atmospheric aerosol samplers was established in the northeastern US starting in February 1977. Size-fractionated samples of the aerosol were collected continuously with four-hour time resolution until the network was dismantled in February 1980. The aerosol-loading and aerosol-chemistry data obtained over this three-year period are summarized in this report. In particular, the samples were analyzed for the sulfate acidity of the aerosol. The acidity was found to be quite high over prolonged periods of time, with the monthly averaged acidity approaching that of ammonium bisulfate at several of the sites. Monthly, seasonal, daily, and diurnal variations in aerosol particle loading and acidity, and sulfate, ammonium, and nitrate ion concentrations are presented. The aerosol-chemistry data are tabulated separately for each of the sampling sites.
Date: November 1981
Creator: Johnson, S. A.; Kumar, R.; Cunningham, P. T. & Lang, T. A.
Partner: UNT Libraries Government Documents Department

The System Uranium-Nitrogen

Description: Report discussing experiments in which the uranium-nitrogen system was "subjected to chemical and x-ray study." The results of these studies "require that previously published descriptions of the system and formulas for the nitrides be replaced."
Date: 1948
Creator: Rundle, Robert Eugene; Baensigur, N. C.; Newton, A. S.; Deane, A. H.; Butler, T. A.; Johns, I. B. et al.
Partner: UNT Libraries Government Documents Department

Investigation of induced unimolecular decomposition for development of visible chemical lasers. Quarterly progress report, 1 May 1976--1 August 1976

Description: Progress during the first quarterly period of the subject contract is summarized. A technical review of the azide literature has essentially been completed. A number of interesting reactions of azides which potentially lead to electronic excitation have been identified. However, uncertainties in state-specific mechanisms, branching ratios, and rate constants do exist. To evaluate the potential of azide chemistry for a short wavelength laser, an experiment is being designed to determine some of the critical, but unknown, information and data.
Date: August 1, 1976
Creator: Piper, L G & Taylor, R L
Partner: UNT Libraries Government Documents Department

Determination of the Forms of Nitrogen Released in Coal Tar During Rapid Devolatilization. Semi-annual report, May 1-October 31, 1997

Description: The primary objective of this work is to determine the forms of nitrogen in coal that lead to nitrogen release during devolatilization. Experiments are to be performed in two existing laminar flow reactors available at Brigham Young University, which are both capable of temperatures (up to 2000 K), particle heating rates (104 to 105 K/s), and residence times (up to 500 ms) relevant to conditions commonly encountered in industrial pulverized coal combustors. The forms of nitrogen in coal, char, and tar samples are analyzed using state-of-the-art techniques, including nuclear magnetic resonance (NMR), X-Ray photoelectron spectroscopy (XPS), and high resolution nitrogen-specific chromatography. These sophisticated analysis techniques are being performed in collaboration with other researchers at BYU, the University of Utah, and industrial organizations. Coals have been obtained as a function of rank, including eight coals from the University of Utah that are to be used in pilot scale tests in support of the DOE Coal-2000 HIPPS (High Performance Power Systems) and LEBS (Low- Emission Boiler Systems) programs. Anticipated results from the proposed research are (a) nitrogen release parameters during devolatilization for specific coals pertinent to the HIPPS and LEBS projects, (b) better fundamental understanding of the chemistry of nitrogen release, and (c) a nitrogen release submodel based on fundamental chemistry that may be more widely applicable than existing empirical relationships.
Date: October 31, 1997
Creator: Fletcher, T.H., Goldberg, P.
Partner: UNT Libraries Government Documents Department

Electrochemically-modulated liquid chromatography (EMLC): Column design, retention processes, and applications

Description: This work describes the continued development of a new separation technique, electrochemically-modulated liquid chromatography (EMLC), from column design, retention mechanisms to pharmaceutical applications. The introduction section provides a literature review of the technique as well as a brief overview of the research in each of the chapters. This section is followed by four chapters which investigate the issues of EMLC column design, the retention mechanism of monosubstituted aromatic compounds, and the EMLC-based applications to two important classes of pharmaceutical compounds (i.e., corticosteroids and benzodiazepines). These four sections have been removed to process separately for inclusion on the database. The dissertation concludes with a general summary, a prospectus, and a list of references cited in the General Introduction. 32 refs.
Date: October 8, 1997
Creator: Ting, E. Y.
Partner: UNT Libraries Government Documents Department

Radiation Chemistry of Synthetic Waste

Description: The yield of hydrogen from radiolysis of aqueous solutions is substantially reduced by the presence of nitrate and nitrite in the waste solutions. Nitrate is more efficient in scavenging the precursors to hydrogen than is nitrite, therefore, the latter should be maintained at higher levels if minimization of radiolytic gas production is required. Nitrate is the major scavenger for e(sub aq)(sup (minus)) and nitrite is the major scavenger for H atoms. At the concentration levels of the waste solutions some fraction of the radiation energy will be absorbed directly by the solutes, primarily the nitrate/nitrite components. Organic additive will increase the generation of hydrogen and mechanistic information is available to allow predictive modeling of trends in the rate of the generation. Physical parameters such as temperature, viscosity, and pressure will not significantly affect the gas generation relative to its generation under normal conditions. Radiolytic generation of N2O is very inefficient in the absence of organic solutes. No mechanistic information is available on its generation in the presence of organic additives. At the concentration levels of the inorganic salts in the waste solutions, it will be very difficult to find a chemical additive that could efficiently reduce the yield of the generated hydrogen, except, perhaps, increasing the concentration of the nitrite/nitrate components.
Date: November 1991
Creator: Meisel, Dan; Diamond, H.; Horwitz, E. P.; Jonah, Charles D.; Matheson, Max S.; Sauer, M. C. et al.
Partner: UNT Libraries Government Documents Department

Studies of Nitrogen-containing Compounds Having Pyrethroid-like Bioactivity

Description: During recent years most of the successful developments in pyrethroids have been primarily concerned with structural or compositional variations. As a part of our continuing interest in pyrethroid insecticides, nitrogen-containing compounds having pyrethroid-like structures were synthesized. Seven prolinate compounds, N-(substituted)-phenyl-prolinates and N-carbobenzoxy-prolinates were coupled with known pyrethroid alcohols. These structural variations which "locked in" a specific conformation between the nitrogen and chiral a-carbon in the acid moiety of fluvalinate were studied to determine the influence of certain conformations on insecticidal toxicity. The toxicity data for the prolinate compounds showed intermediate mortality against nonresistant cockroaches. It was concluded that the conformation imposed by the proline ring portion of the esters was probably close to the favored conformation for interaction of fluvalinate-like pyrethroids with the insect receptor site. A second series of nitrogen-containing compounds, twenty-five carbamate esters resulting from the condensation of N-isopropyl-(substituted)-anilines and N-alkyl-(substituted)-benzylamines with appropriate pyrethroid alcohols were studied for insecticidal activity. These studies were conducted on pyrethroid-susceptible houseflies. Some of the carbamate esters exhibited high toxicity when synergized by piperonyl butoxide. For example, the toxicity ( LD 50 ) of O-a-cyano-3-phenoxyfaenzyl-N-a,a-dimethyl-4-bromo-benzyl carbamate was 0.012 ug/g, which is significantly greater than that reported for the potent pyrethroid, fenvalerate. Correlations of insecticidal activity with respect to structure and conformational factors of the carbamate esters have been made. The N-isopropyl substituent decreases insecticidal activity in the N-benzyl-derived compounds, while the N-isopropyl substituent enhances activity in the N-phenyl-derived compounds. Certain substituents on the phenyl ring of both analogs greatly affect insecticidal potency of the carbamate esters. Also, some alkyl substituents (especially, a,cx-dimethyl and a-cyclopropyl groups) on the benzylic carbon of the benzylamine series enhance toxicity. The a,a-dimethyl branching of the N-benzyl carbamate approximates the steric shape given by the gemdimethyl group for conventional cyclopropane ring-containing pyrethroids. The N-benzyl compounds are significantly synergized by ...
Date: August 1989
Creator: Lee, Jimmy Jing-Ming, 1955-
Partner: UNT Libraries

vic-DIOXIMES AS ANALYTICAL REAGENTS

Description: A review of research that has contributed to a better understanding of the solubility relations among vicdioximes is presented. Included are sections on synthesis, analysis, structure, and analytical uses of these complexes (J.R.D.)
Date: March 1, 1962
Creator: Banks, C.V.
Partner: UNT Libraries Government Documents Department

Chemical and biological studies on nucleic acids and derivatives. Progress report, May 1, 1975--July 31, 1976

Description: The photochemical products from N-oxidized purines in solution are strongly dependent on the tautomeric and ionic state of the compounds. Studies have been done on the effect of pH on the quantum efficiencies of photoreduction and photorearrangement of a 1-hydroxypurine, a purine 3-oxide and hypoxanthine 3-oxide, a compound that exists as a tautomeric N-oxide-N-hydroxyl equilibrium. The quantum yields for each photoreaction from each tautomer of the nonionized species and from the anions have been determined. In every case photoreduction is promoted in the presence of triplet sensitizers.
Date: October 1, 1976
Creator: Brown, G. B. & Parham, J. C.
Partner: UNT Libraries Government Documents Department

Formation of Nitrogen Oxides by Alpha Particle Irradiation of the System N₂-CO₂

Description: Abstract: "The reaction between nitrogen and carbon dioxide, under irradiation with 40 Mev alpha particles from the Berkeley 60 inch cyclotron, was studied at gas temperatures near 50 C and total pressures of about 600 millimeters of Hg, contained in Pyrex capsules. The range of gas compositions investigated included the pure components, as well as mixtures with and without trace oxygen. In all mixtures, a steady state concentration of nitrogen oxides of about 0.15 millimeter was reached after a few microampere hours exposure. The mass-spectrometer analytical procedure employed did not permit identification of the individual species of oxides present. This report is based on studies conducted for the Atomic Energy Commission under Contract AT-11-1-GEN-8."
Date: March 24, 1953
Creator: Steidlitz, M. E. & Feldman, M. H.
Partner: UNT Libraries Government Documents Department

Calculation notes in support of ammonia releases from waste tank ventilation systems

Description: Ammonia is generated in waste tanks via the degradation of nitrogen compounds. The ammonia is released from the liquids by a mechanism which is dependent on temperature, pH, ionic strength and ammonia concentration. The release of ammonia to the environment occurs via diffusion of ammonia through a stagnant air mass and into the ventilation system.
Date: September 5, 1996
Creator: Wojdac, L. F.
Partner: UNT Libraries Government Documents Department

CONTROLLED-POTENTIAL COULOMETRIC TITRATION OF URANIUM(VI) IN THE PRESENCE OF NITRATE

Description: A study into the use of sulfamic acld as a nitritedestroying reagent in the controlled-potentlal coulometrlc tltratlon method for uranlum(VI) was made. When nltrites are thus destroyed, the tltration ls much less subject to error from HNO/sub 3/. The results of titratlons of known amounts of uranlum(VI) in the presence of varlous amounts of HNO/sub 3/, Th(NO/sub 3/)/sub 4/, Al(NO/sub 3/ )/sub 4/, and LiNO/sub 3/ are given. (auth)
Date: January 17, 1962
Creator: Shults, W.D.
Partner: UNT Libraries Government Documents Department

Heat of detonation, the cylinder test, and performance munitions

Description: Heats of detonation of CHNO explosives correlate well with copper cylinder test expansion data. The detonation products/calorimetry data can be used to estimate performance in the cylinder test, in munitions, and for new molecules or mixtures of explosives before these are made. Confidence in the accuracy of the performance estimates is presently limited by large deviations of a few materials from the regression predictions; but these same deviations, as in the insensitive explosive DINGU and the low carbon systems, appear to be sources of information useful for detonation and explosives research. The performance correlations are functions more of the detonation products and thermochemical energy than they are of the familiar parameters of detonation pressure and velocity, and the predictions are closer to a regression line on average than are those provided by CJ calculations. The prediction computations are simple but the measurements (detonation calorimetry/products and cylinder experiments) are not. 17 refs., 5 tabs.
Date: January 1, 1989
Creator: Akst, I.B.
Partner: UNT Libraries Government Documents Department

Bibliography of mass spectroscopy literature for 1973 compiled by a computer method. Bibliography and author index. [About 8,000 citations]

Description: This report covers the year 1973, and lists approximately 8,000 articles of interest to mass spectroscopists. This report consists of three sections, a Bibliography section, an Author Index section and a Key Word Out of Context Index (KWOC Index) section. The Bibliography section lists the authors, the title and the publication data for each article. The Author Index lists the authors' names and the reference numbers of their articles. The KWOC Index lists the key words, the reference numbers of the articles in which the key word appears and the first 100 characters of the title.
Date: June 1, 1976
Creator: Capellen, J.; Svec, H. J.; Sage, C. R. & Sun, R. (comps.)
Partner: UNT Libraries Government Documents Department

Environmental significance of biocatalytic conversion of low grade oils

Description: Studies dealing with the interactions between extremophilic microorganisms and crude oils have led to the identification of biocatalysts which through multiple biochemical reactions catalyze desulfurization, denitrogenation, and demetalation reactions in oils. Concurrently, the oils are also converted to lighter oils. These complex biochemical reactions have served as models in the development of the crude oil bioconversion technology to be applied prior to the treatment of oils by conventional chemical processes. In practical terms, this means that the efficiency of the existing technology is being enhanced. For example, the recently introduced additional regulation for the emission of nitrogen oxides in some states restricts further the kinds of oils that may be used in burners. The biocatalysts being developed in this laboratory selectively interact with nitrogen compounds, i.e. basic and neutral types present in the oil and, hence, affect the fuel NOx production. This, in turn, has a cost-efficient influence on the processed oils and their consumption. In this paper, these cost-efficient and beneficial effects will be discussed in terms of produced oils, the lowering of sulfur and nitrogen contents, and the effect on products, as well as the longevity of catalysts due to the removal of heteroatoms and metal containing compounds found in crudes.
Date: September 1, 1996
Creator: Lin, M.S.; Premuzic, E.T.; Lian, H.; Zhou, W.M. & Yablon, J.
Partner: UNT Libraries Government Documents Department

[Towards computer-aided catalyst design: Three effective core potential studies of C-H activation]. Final report

Description: Research in the initial grant period focused on computational studies relevant to the selective activation of methane, the prime component of natural gas. Reaction coordinates for methane activation by experimental models were delineated, as well as the bonding and structure of complexes that effect this important reaction. This research, highlighted in the following sections, also provided the impetus for further development, and application of methods for modeling metal-containing catalysts. Sections of the report describe the following: methane activation by multiple-bonded transition metal complexes; computational lanthanide chemistry; and methane activation by non-imido, multiple-bonded ligands.
Date: December 31, 1998
Partner: UNT Libraries Government Documents Department