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Sample records for organic nitrogen compounds

  1. The Atmospheric Fate of Organic Nitrogen Compounds

    NASA Astrophysics Data System (ADS)

    Borduas, Nadine

    Organic nitrogen compounds are present in our atmosphere from biogenic and anthropogenic sources and have impacts on air quality and climate. Due to recent advances in instrumentation, these compounds are being detected in the gas and particle phases, raising questions as to their source, processing and sinks in the environment. With their recently identified role as contributors to aerosol formation and growth, their novel large scale use as solvents in carbon capture and storage (CCS) technology and their emissions from cigarette smoke, it is now important to address the gaps in our understanding of the fate of organic nitrogen. Experimentally and theoretically, I studied the chemical atmospheric fate of specific organic nitrogen compounds in the amine, amide and isocyanate families, yielding information that can be used in chemical transport models to assess the fate of this emerging class of atmospheric molecules. I performed kinetic laboratory studies in a smog chamber to measure the room temperature rate coefficient for reaction with the hydroxyl radical of monoethanolamine, nicotine, and five different amides. I employed online-mass spectrometry techniques to quantify the oxidation products. I found that amines react quickly with OH radicals with lifetimes of a few hours under sunlit conditions, producing amides as oxidation products. My studies on amides revealed that they have much longer lifetimes in the atmosphere, ranging from a few hours to a week. Photo-oxidation of amides produces isocyanates and I investigated these mechanisms in detail using ab initio calculations. Furthermore, I experimentally measured isocyanic acid's Henry's Law constant as well as its hydrolysis rate constants to better understand its sinks in the atmosphere. Finally, I re-examined the structure-activity relationship (SAR) of organic nitrogen molecules for improved model parameterizations.

  2. Adsorption of Compounds that Mimic Urban Stormwater Dissolved Organic Nitrogen.

    PubMed

    Mohtadi, Mehrdad; James, Bruce R; Davis, Allen P

    2017-02-01

      Stormwater runoff carrying nitrogen can accelerate eutrophication. Bioretention facilities are among low impact development systems which are commonly used to manage urban stormwater quality and quantity. They are, however, not designed to remove dissolved organic nitrogen (DON) and may become a net DON exporter. Adsorption of seven organic nitrogenous compounds onto several adsorbents was examined. Batch adsorption study revealed that coal activated carbon (AC) exhibited the best performance in adsorption of the selected organic nitrogenous compounds. The highest adsorption capacity of coal AC was 0.4 mg N/g for pyrrole at an equilibrium concentration of 0.02 mg N/L, while adsorption was not detectable for urea at the same equilibrium concentration. The fastest compound to reach equilibrium adsorption capacity onto the coal AC was pyrrole (1 hour). The adsorption capacity of the coal AC for pyrrole and N-acetyl-d-glucosamine and 1-hour contact time is recommended for designing bioretention systems targeting organic nitrogenous compounds.

  3. Uptake of organic sulfur and nitrogen compounds by aerosols

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Efforts have been undertaken to monitor and model the uptake of medium-sized organic compounds found above agricultural waste. Field effects performed by our collaborators monitor both the gas phase compounds present in a chicken house in Kentucky; using PILS-IC sampling, the contents of PM2.5 parti...

  4. Predicting liquid densities of organic compounds: II, Nitrogen and sulfur compounds

    SciTech Connect

    Wood, G.O.; Weaver, T.B.

    1993-02-01

    Correlations of liquid densities have been extended to more classes of organic compounds. The products of liquid density and molecular weight at or near 20{degrees}C were previously found to be linear functions of the number and types of carbon atoms in the molecule. Cyclic carbon atoms contributed more to density than carbon atoms not part of a ring structure. Carbon atoms which occupy two rings have since been found to contribute even different increments. Additional databases of liquid densities have been set up for compounds with cyclic oxygen atoms, cyclic and noncyclic nitrogen atoms, and cyclic and noncyclic sulfur atoms. Correlation parameters have been obtained by fitting these data by least squares minimization.

  5. Nitrogen Containing Organic Compounds and Oligomers in Secondary Organic Aerosol Formed by Photooxidation of Isoprene

    SciTech Connect

    Nguyen, Tran B.; Laskin, Julia; Laskin, Alexander; Nizkorodov, Serguei

    2011-07-06

    Electrospray ionization high-resolution mass spectrometry (ESI HR-MS) was used to probe molecular structures of oligomers in secondary organic aerosol (SOA) generated in laboratory experiments on isoprene photooxidation at low- and high-NOx conditions. Up to 80-90% of the observed products are oligomers and up to 33% are nitrogen-containing organic compounds (NOC). We observe oligomers with up to 8 monomer units in length. Tandem mass spectrometry (MSn) confirms NOC compounds are organic nitrates and elucidates plausible chemical building blocks contributing to oligomer formation. Most organic nitrates are comprised of methylglyceric acid units. Other important multifunctional C2-C5 monomer units are identified including methylglyoxal, hydroxyacetone, hydroxyacetic acid, glycolaldehyde, and 2-methyltetrols. The majority of the NOC oligomers contain only one nitrate moiety resulting in a low average N:C ratio of 0.019. Average O:C ratios of the detected SOA compounds are 0.54 under the low-NOx conditions and 0.83 under the high-NOx conditions. Our results underscore the importance of isoprene photooxidation as a source of NOC in organic particulate matter.

  6. THE REACTIONS OF NITROGEN ATOMS WITH ORGANIC COMPOUNDS

    DTIC Science & Technology

    mechanism. Relatively crude measurements were made of the intensity and rough wavelength distribution of light emitted during reactions of nitrogen atoms...the intensity of light emission from the reactions of several substrates was measured photometrically with 1P21 photomultiplier tubes located at two...ethylene, propylene, ethane, dimethyl ether, tetrafluoromethane and diborane. Emission intensities with ethane, propylene, diborane and ethylene were comparable in these experiments. (Author)

  7. Microdetermination of nitrogen in organic compounds by the sodium fusion-spectrophotometric method

    SciTech Connect

    Breda, E.J.

    1985-04-01

    In the absence of the preferred Dumas nitrogen apparatus or the more sophisticated nitrogen analyzers, a micro-Parr bomb can serve to determine microquantities of nitrogen in organic compounds. The sample or compound, either solid or nonaqueous liquid, is decomposed by fusing with metallic sodium in a sealed nickel bomb. The nitrogen is converted to sodium cyanide. The excess sodium is decomposed with absolute ethanol. The solution is adjusted to pH 7.1-7.2 with dilute hydrochloric acid and analyzed for cyanide by the Chloramine-T and mixed pyridine/pyrazolone reagent method. The absorbance of the blue color formed is measured with a spectrophotometer at 615 nm. The amount of cyanide found is converted to the equivalent nitrogen in the compound. The method is not as rapid as desired but it is handy, simple, and economical. As with any micro or semimicro method, this procedure is sensitive to technique. Compounds must contain carbon and be essentially free of moisture. 5 references, 1 table.

  8. Thermal and Photochemical Oxidation of Organic Compounds on Model Mineral Dust Particles Exposed to Nitrogen Dioxide

    NASA Astrophysics Data System (ADS)

    Raff, J.; Finlayson-Pitts, B. J.; Szanyi, J.

    2010-12-01

    Alumina is an important component of airborne dust particles as well as of building materials and soils found in the tropospheric boundary layer. While the uptake and reactions of oxides of nitrogen and their photochemistry on alumina have been reported in the past, little is known about the chemistry when organics are also present. Fourier transform infrared (FTIR) spectroscopy was used to study at ~23 °C reactions of NO2 on γ-Al2O3 particles that had been derivatized using 7-octenyltrichlorosilane to form a self-assembled monolayer (SAM). For comparison, the reactions with untreated γ-Al2O3 were also studied. In both cases, the particles were exposed to water vapor prior to NO2 to provide adsorbed water for reaction. As expected, surface-bound HONO, NO2-, and NO3- were formed. Surprisingly, oxidation of the organic by surface-bound nitrogen oxides was observed in the dark, forming organo-nitrogen products identified as nitronates (R2C=NO2-). Oxidation was more rapid under irradiation (λ > 290 nm) and formed organic nitrates and carbonyl compounds and/or peroxy nitrates in addition to the products observed in the dark. Mass spectrometry of the gas phase during irradiation revealed the production of NO, CO2, and CO. These studies provide evidence for oxidation of organic compounds on particles and boundary layer surfaces that are exposed to air containing oxides of nitrogen, as well as new pathways for the formation of nitrogen-containing compounds on these surfaces.

  9. Molecular Characterization of Nitrogen Containing Organic Compounds in Biomass Burning Aerosols Using High Resolution Mass Spectrometry

    SciTech Connect

    Laskin, Alexander; Smith, Jeffrey S.; Laskin, Julia

    2009-05-13

    Although nitrogen-containing organic compounds (NOC) are important components of atmospheric aerosols, little is known about their chemical compositions. Here we present detailed characterization of the NOC constituents of biomass burning aerosol (BBA) samples using high resolution electrospray ionization mass spectrometry (ESI/MS). Accurate mass measurements combined with MS/MS fragmentation experiments of selected ions were used to assign molecular structures to individual NOC species. Our results indicate that N-heterocyclic alkaloid compounds - species naturally produced by plants and living organisms - comprise a substantial fraction of NOC in BBA samples collected from test burns of five biomass fuels. High abundance of alkaloids in test burns of ponderosa pine - a widespread tree in the western U.S. areas frequently affected by large scale fires - suggests that N-heterocyclic alkaloids in BBA can play a significant role in dry and wet deposition of fixed nitrogen in this region.

  10. Isotopic disproportionation during hydrogen isotopic analysis of nitrogen-bearing organic compounds

    USGS Publications Warehouse

    Nair, Sreejesh; Geilmann, Heike; Coplen, Tyler B.; Qi, Haiping; Gehre, Matthias; Schimmelmann, Arndt; Brand, Willi A.

    2015-01-01

    Rationale High-precision hydrogen isotope ratio analysis of nitrogen-bearing organic materials using high-temperature conversion (HTC) techniques has proven troublesome in the past. Formation of reaction products other than molecular hydrogen (H2) has been suspected as a possible cause of incomplete H2 yield and hydrogen isotopic fractionation. Methods The classical HTC reactor setup and a modified version including elemental chromium, both operated at temperatures in excess of 1400 °C, have been compared using a selection of nitrogen-bearing organic compounds, including caffeine. A focus of the experiments was to avoid or suppress hydrogen cyanide (HCN) formation and to reach quantitative H2 yields. The technique also was optimized to provide acceptable sample throughput. Results The classical HTC reaction of a number of selected compounds exhibited H2 yields from 60 to 90 %. Yields close to 100 % were measured for the experiments with the chromium-enhanced reactor. The δ2H values also were substantially different between the two types of experiments. For the majority of the compounds studied, a highly significant relationship was observed between the amount of missing H2and the number of nitrogen atoms in the molecules, suggesting the pyrolytic formation of HCN as a byproduct. A similar linear relationship was found between the amount of missing H2 and the observed hydrogen isotopic result, reflecting isotopic fractionation. Conclusions The classical HTC technique to produce H2 from organic materials using high temperatures in the presence of glassy carbon is not suitable for nitrogen-bearing compounds. Adding chromium to the reaction zone improves the yield to 100 % in most cases. The initial formation of HCN is accompanied by a strong hydrogen isotope effect, with the observed hydrogen isotope results on H2 being substantially shifted to more negative δ2H values. The reaction can be understood as an initial disproportionation leading to H2 and HCN

  11. Analysis of Nitrogen Containing Organic Compounds in Biomass Burning Aerosols Using High Resolution Mass Spectrometry

    NASA Astrophysics Data System (ADS)

    Laskin, A.; Smith, J. S.; Laskin, J.

    2009-05-01

    Chemical characterization of atmospheric aerosols presents a serious analytical challenge because of the complexity of particulate matter analyte composed of a large number of compounds with a wide range of molecular structures, physico-chemical properties, and reactivity. In this study the chemical composition of the nitrogen containing organic (NOC) constituents of biomass burning aerosol (BBA) samples is characterized by high-resolution electrospray ionization mass spectrometry (ESI/MS). Accurate mass measurements combined with MS/MS fragmentation experiments of selected ions were used to assign molecular structures to individual NOC species. Our results indicate that N-heterocyclic alkaloid compounds - species naturally produced by plants and living organisms - comprise a substantial fraction of NOC in BBA samples collected from test burns of five biomass fuels. High abundance of alkaloids in test burns of ponderosa pine - a widespread tree in the western U.S. areas frequently affected by large scale fires - suggests that N-heterocyclic alkaloids in BBA may play a significant role in dry and wet deposition of fixed nitrogen in this region. Atmospheric processing and chemical transformations of alkaloids in the particulate phase will be discussed.

  12. Membrane rejection of nitrogen compounds

    NASA Technical Reports Server (NTRS)

    Lee, S.; Lueptow, R. M.

    2001-01-01

    Rejection characteristics of nitrogen compounds were examined for reverse osmosis, nanofiltration, and low-pressure reverse osmosis membranes. The rejection of nitrogen compounds is explained by integrating experimental results with calculations using the extended Nernst-Planck model coupled with a steric hindrance model. The molecular weight and chemical structure of nitrogen compounds appear to be less important in determining rejection than electrostatic properties. The rejection is greatest when the Donnan potential exceeds 0.05 V or when the ratio of the solute radius to the pore radius is greater than 0.8. The transport of solute in the pore is dominated by diffusion, although convective transport is significant for organic nitrogen compounds. Electromigration contributes negligibly to the overall solute transport in the membrane. Urea, a small organic compound, has lower rejection than ionic compounds such as ammonium, nitrate, and nitrite, indicating the critical role of electrostatic interaction in rejection. This suggests that better treatment efficiency for organic nitrogen compounds can be obtained after ammonification of urea.

  13. Chemical Stabilization of Soil Organic Nitrogen by Phenolic Lignin Compounds in Anaerobic Agrosystems

    NASA Astrophysics Data System (ADS)

    Olk, D. C.

    2004-12-01

    In tropical Asia, continuous cropping of paddy rice promotes the covalent binding of soil organic nitrogen (N) by phenolic lignin residues, which in turns appears to contribute to substantial long-term declines in availability of soil organic N and in grain yield. A newly developed technique of nuclear magnetic resonance spectroscopy that selects for carbon atoms bound to N was applied to a young humic fraction to directly observe an agronomically significant greater quantity of organic N (difference of 55 kg per hectare) that was bound by lignin residues in a triple-cropped rice soil compared to a nearby aerated soil. The resulting compound was an anilide. Crop residues are the parent material of soil organic matter in agricultural soils, and their anaerobic decomposition was found to slow microbially driven mineralization of both soil organic N and soil phenols during the rice season, compared to aerobic decomposition. Through use of 15N-labeled fertilizer, stabilization of soil organic N was shown to be more extensive than binding of inorganic fertilizer N. Similar results were gained in eastern Arkansas when comparing a more anaerobic continuous rice rotation to the conventional rice-soybean rotation. Future studies of covalently bound N will consider both its seasonal dynamics and its significance to long-term yield trends. Agronomic observations suggest that covalent binding of nutrients by lignin residues might also occur in other agrosystems with anaerobic decomposition of crop residues, including paddy taro in Hawaii and to a lesser extent no-tilled crops in regions with cool, wet springtime weather.

  14. USE OF GIS AND ANCILLARY VARIABLES TO PREDICT VOLATILE ORGANIC COMPOUND AND NITROGEN DIOXIDE LEVELS AT UNMONITORED LOCATIONS

    EPA Science Inventory

    This paper presents a GIS-based regression spatial method, known as land-use regression (LUR) modeling, to estimate ambient air pollution exposures used in the EPA El Paso Children's Health Study. Passive measurements of select volatile organic compounds (VOC) and nitrogen dioxi...

  15. Nitrogen-rich higher-molecular soil organic compounds patterned by lignin degradation products: Considerations on the nature of soil organic nitrogen

    NASA Astrophysics Data System (ADS)

    Liebner, Falk; Bertoli, Luca; Pour, Georg; Klinger, Karl; Ragab, Tamer; Rosenau, Thomas

    2016-04-01

    The pathways leading to accumulation of covalently bonded nitrogen in higher-molecular soil organic matter (SOM) are still a controversial issue in soil science and geochemistry. Similarly, structural elucidation of the variety of the types of nitrogenous moieties present in SOM is still in its infancy even though recent NMR studies suggest amide-type nitrogen to form the majority of organically bonded nitrogen which is, however, frequently not in accordance with the results of wet-chemical analyses. Following the modified polyphenol theory of Flaig and Kononova but fully aware of the imperfection of a semi-abiotic simulation approach, this work communicates the results of a study that investigated some potential nitrogen accumulation pathways occurring in the re-condensation branch of the theory following the reactions between well-known low-molecular lignin and carbohydrate degradation products with nitrogenous nucleophiles occurring in soils under aerobic conditions. Different low-molecular degradation products of lignin, cellulose, and hemicellulose, such as hydroquinone, methoxyhydroquinone, p-benzoquinone, 2,5-dihydroxy-[1,4]benzoquinone, glucose, xylose, and the respective polysaccharides, i.e. cellulose, xylan as well as various types of lignin were subjected to a joint treatment with oxygen and low-molecular N-nucleophiles, such as ammonia, amines, and amino acids in aqueous conditions, partly using respective 15N labeled compounds for further 15N CPMAS NMR studies. Product mixtures derived from mono- and polysaccharides have been comprehensively fractionated and analyzed by GC/MS after derivatization. Some of ammoxidized polyphenols and quinones have been analyzed by X-ray photoelectron spectroscopy. Some products, such as those obtained from ammoxidation of methoxy hydroquinone using 15N labeled ammonia were fractionated following the IHSS protocol. Individual humin (H), humic acid (HA), and fulvic acid (FA) fractions were subjected to elemental analyses

  16. Performance evaluation of the UV/H2O2 process on selected nitrogenous organic compounds: reductions of organic contents vs. corresponding C-, N-DBPs formations.

    PubMed

    Chen, Huei-Wen; Chen, Chia-Yang; Wang, Gen-Shuh

    2011-10-01

    The presence of various organic contaminants in water sources is of concern due to their direct threats to human health and potential to react with disinfectants to form carcinogenic byproducts including trihalomethanes, haloacetic acids and nitrosamines in finished water. This study applied both medium-pressure and low-pressure ultraviolet light coupled with hydrogen peroxide (UV/H2O2) to evaluate its efficacy for degradation of selected nitrogenous organic compounds and corresponding disinfection byproduct (DBP) formation. Six organic compounds were chosen as target precursors based on their nitrogen contents and molecular structures. The results showed that higher oxidation capacity resulted in better reduction of organic matters and DBP formation potentials (DBPFPs). However, insufficient contact time and oxidant doses could lead to a rise of DBPFPs in the early stages of UV/H2O2 reactions. A greater percentage removal was achieved for organic carbon than organic nitrogen after UV/H2O2 treatment, especially for compounds with complicated structure such as diltiazem. During the UV/H2O2 treatment, the intermediate products include tertiary amine, dimethyl amine (DMA) or DMA-like structures, which are N-nitrosodimethylamine (NDMA) precursors after chlorination or chloramination. Furthermore, it was observed that using dissolved organic nitrogen and DMA to predict NDMAFP could lead to biased conclusions because of the complex nature of nitrogenous matters in aqueous environments.

  17. Non-thermal plasma techniques for abatement of volatile organic compounds and nitrogen oxides

    SciTech Connect

    Penetrante, B.M.; Hsiao, M.C.; Bardsley, J.N.; Merritt, B.T.; Vogtlin, G.E.; Wallman, P.H.; Kuthi, A.; Burkhart, C.P.; Bayless, J.R.

    1995-12-04

    Non-thermal plasma processing is an emerging technology for the abatement of volatile organic compounds (VOCs) and nitrogen oxides (NO{sub x}) in atmospheric-pressure air streams. Either electrical discharge or electron beam methods can produce these plasmas. Each of these methods can be implemented in many ways. There are many types of electrical discharge reactors, the variants depending on the electrode configuration and electrical power supply (pulsed, AC or DC). Two of the more extensively investigated types of discharge reactors are based on the pulsed corona and dielectric-barrier discharge. Recently, compact low-energy (<200 keV) electron accelerators have been developed to meet the requirements of industrial applications such as crosslinking of polymer materials, curing of solvent-free coatings, and drying of printing inks. Special materials have also been developed to make the window thin and rugged. Some of these compact electron beam sources are already commercially available and could be utilized for many pollution control applications. In this paper we will present a comparative assessment of various nonthermal plasma reactors. The thrust of our work has been two-fold: (1) to understand the scalability of various non-thermal plasma reactors by focusing on the energy efficiency of the electron and chemical kinetics, and (2) to identify the byproducts to ensure that the effluent gases from the processor are either benign or much easier and less expensive to dispose of compared to the original pollutants. We will present experimental results using a compact electron beam reactor and various types of electrical discharge reactors. We have used these reactors to study the removal of NO{sub x} and a wide variety of VOCS. We have studied the effects of background gas composition and gas temperature on the decomposition chemistry.

  18. Reduction of nitrogen compounds in oceanic basement and its implications for HCN formation and abiotic organic synthesis

    PubMed Central

    2009-01-01

    Hydrogen cyanide is an excellent organic reagent and is central to most of the reaction pathways leading to abiotic formation of simple organic compounds containing nitrogen, such as amino acids, purines and pyrimidines. Reduced carbon and nitrogen precursor compounds for the synthesis of HCN may be formed under off-axis hydrothermal conditions in oceanic lithosphere in the presence of native Fe and Ni and are adsorbed on authigenic layer silicates and zeolites. The native metals as well as the molecular hydrogen reducing CO2 to CO/CH4 and NO3-/NO2- to NH3/NH4+ are a result of serpentinization of mafic rocks. Oceanic plates are conveyor belts of reduced carbon and nitrogen compounds from the off-axis hydrothermal environments to the subduction zones, where compaction, dehydration, desiccation and diagenetic reactions affect the organic precursors. CO/CH4 and NH3/NH4+ in fluids distilled out of layer silicates and zeolites in the subducting plate at an early stage of subduction will react upon heating and form HCN, which is then available for further organic reactions to, for instance, carbohydrates, nucleosides or even nucleotides, under alkaline conditions in hydrated mantle rocks of the overriding plate. Convergent margins in the initial phase of subduction must, therefore, be considered the most potent sites for prebiotic reactions on Earth. This means that origin of life processes are, perhaps, only possible on planets where some kind of plate tectonics occur. PMID:19849830

  19. Peculiarities in the formation of complex organic compounds in a nitrogen-methane atmosphere during hypervelocity impacts

    NASA Astrophysics Data System (ADS)

    Zaitsev, M. A.; Gerasimov, M. V.; Safonova, E. N.; Vasiljeva, A. S.

    2016-03-01

    Results of the experiments on model impact vaporization of peridotite, a mineral analogue of stony asteroids, in a nitrogen-methane atmosphere are presented. Nd-glass laser (γ = 1.06 µm) was used for simulation. Pulse energy was ~600-700 J, pulse duration ~10-3 s, vaporization tempereature ~4000-5000 K. The gaseous medium (96% vol. of N2 and 4% vol. of CH4, P = 1 atm) was a possible analogue of early atmospheres of terrestrial planets and corresponded to the present-day atmosphere composition of Titan, a satellite of Saturn. By means of pyrolytic gas chromatography/mass spectrometry, it is shown that solid condensates obtained in laser experiments contain relatively complex lowand high-molecular weight (kerogen-like) organic compounds. The main products of condensate pyrolysis were benzene and alkyl benzenes (including long-chain ones), unbranched aliphatic hydrocarbons, and various nitrogen-containing compounds (aliphatic and aromatic nitriles and pyrrol). It is shown that the nitrogen-methane atmosphere favors the formation of complex organic compounds upon hypervelocity impacts with the participation of stony bodies even with a small methane content in it. In this process, falling bodies may not contain carbon, hydrogen, and other chemical elements necessary for the formation of the organic matter. In such conditions, a noticeable contribution to the impact-induced synthesis of complex organic substances is probably made by heterogeneous catalytic reactions, in particular, Fischer-Tropsch type reactions.

  20. Reduction of nitrogen compounds in oceanic basement and its implications for HCN formation and abiotic organic synthesis.

    PubMed

    Holm, Nils G; Neubeck, Anna

    2009-10-22

    Hydrogen cyanide is an excellent organic reagent and is central to most of the reaction pathways leading to abiotic formation of simple organic compounds containing nitrogen, such as amino acids, purines and pyrimidines. Reduced carbon and nitrogen precursor compounds for the synthesis of HCN may be formed under off-axis hydrothermal conditions in oceanic lithosphere in the presence of native Fe and Ni and are adsorbed on authigenic layer silicates and zeolites. The native metals as well as the molecular hydrogen reducing CO2 to CO/CH4 and NO3-/NO2- to NH3/NH4+ are a result of serpentinization of mafic rocks. Oceanic plates are conveyor belts of reduced carbon and nitrogen compounds from the off-axis hydrothermal environments to the subduction zones, where compaction, dehydration, desiccation and diagenetic reactions affect the organic precursors. CO/CH4 and NH3/NH4+ in fluids distilled out of layer silicates and zeolites in the subducting plate at an early stage of subduction will react upon heating and form HCN, which is then available for further organic reactions to, for instance, carbohydrates, nucleosides or even nucleotides, under alkaline conditions in hydrated mantle rocks of the overriding plate. Convergent margins in the initial phase of subduction must, therefore, be considered the most potent sites for prebiotic reactions on Earth. This means that origin of life processes are, perhaps, only possible on planets where some kind of plate tectonics occur.

  1. Formation of nitrate and ammonium ions in titanium dioxide mediated photocatalytic degradation of organic compounds containing nitrogen atoms

    SciTech Connect

    Low, G.K.-C.; McEvoy, S.R.; Matthews, R.W. )

    1991-03-01

    The photocatalytic oxidation of a related series of primary, secondary, and tertiary amines and other nitrogen- and sulfur-containing organic compounds over a UV-illuminated film of TiO{sub 2} has been studied. The compounds were as follows: n-pentylamine, piperidine, pyridine, phenylalanine, desipramine, thioridazine, penicillamine, isosorbide dinitrate, 4-nitrocatechol, 2,4-dinitrophenol, cyclophosphamide, 5-fluorouracil, atrazine, ethylenediaminetetracetic acid, and tetrabutylammonium phosphate. Both ammonium and nitrate ions were formed. The relative concentration of the two ions depended on the nature of the nitrogen in a compound, but was also influenced by the illumination time and concentration of the solute. It was found that for n-pentylamine, piperidine and pyridine, the rate of formation of ammonium ions was n-pentylamine {much gt} pyridine > piperidine. The order of rates of nitrate formation was pyridine = piperidine {much gt} pentylamine. For n-pentylamine the rate of formation of ammonium ions was {approximately}100 times that of nitrate.

  2. Ambient Observations of Organic Nitrogen Compounds in Submicrometer Aerosols in New York Using High Resolution Aerosol Mass Spectrometry

    NASA Astrophysics Data System (ADS)

    Zhou, S.; Ge, X.; Xu, J.; Sun, Y.; Zhang, Q.

    2015-12-01

    Organic nitrogen (ON) compounds, which include amines, nitriles, organic nitrates, amides, and N-containing aromatic heterocycles, are an important class of compounds ubiquitously detected in atmospheric particles and fog and cloud droplets. Previous studies indicate that these compounds can make up a significant fraction (20-80%) of the total nitrogen (N) content in atmospheric condensed phases and play important roles in new particle formation and growth and affecting the optical and hygroscopicity of aerosols. In this study, we report the observation of ON compounds in submicrometer particles (PM1) at two locations in New York based on measurements using Aerodyne high-resolution time-of-flight mass spectrometer (HR-ToF-AMS). One study was conducted as part of the US Department of Energy funded Aerosol Lifecyle - Intensive Operation Period (ALC-IOP) campaign at Brookhaven National Lab (BNL, 40.871˚N, 72.89˚W) in summer, 2011 and the other was conducted at the Queen's College (QC) in New York City (NYC) in summer, 2009. We observed a notable amount of N-containing organic fragment ions, CxHyNp+ and CxHyOzNp+, in the AMS spectra of organic aerosols at both locations and found that they were mainly associated with amino functional groups. Compared with results from lab experiments, the C3H8N+ at m/z = 58 was primarily attributed to trimethylamine. In addition, a significant amount of organonitrates was observed at BNL. Positive matrix factorization (PMF) analysis of the high resolution mass spectra (HRMS) of organic aerosols identified a unique nitrogen-enriched OA (NOA) factor with elevated nitrogen-to-carbon (N/C) at both BNL and QC. Analysis of the size distributions, volatility profiles, and correlations with external tracer indicates that acid-base reactions of amino compounds with sulfate and acidic gas were mainly responsible for the formation of amine salts. Photochemical production was also observed to play a role in the formation of NOA. Bivariate polar

  3. Field Comparison of Passive Air Samplers with Reference Monitors for Ambient Volatile Organic Compounds and Nitrogen Dioxide Under Week-Long Integrals

    EPA Science Inventory

    This study evaluates performance of nitrogen dioxide NO2 and volatile organic compounds (VOC) passive samplers with corresponding reference monitors at two sites in the Detroit, Michigan area during the summer of 2005.

  4. Current emission trends for nitrogen oxides, sulfur dioxide, and volatile organic compounds by month and state: Methodology and results

    SciTech Connect

    Kohout, E.J.; Miller, D.J.; Nieves, L.A.; Rothman, D.S.; Saricks, C.L.; Stodolsky, F.; Hanson, D.A.

    1990-08-01

    This report presents estimates of monthly sulfur dioxide (SO{sub 2}), nitrogen oxides (NO{sub x}), and nonmethane voltatile organic compound (VOC) emissions by sector, region, and state in the contiguous United States for the years 1975 through 1988. This work has been funded as part of the National Acid Precipitation Assessment Program's Emissions and Controls Task Group by the US Department of Energy (DOE) Office of Fossil Energy (FE). The DOE project officer is Edward C. Trexler, DOE/FE Office of Planning and Environment.

  5. Current emission trends for nitrogen oxides, sulfur dioxide, and volatile organic compounds by month and state: Methodology and results

    SciTech Connect

    Kohout, E.J.; Miller, D.J.; Nieves, L.A.; Rothman, D.S.; Saricks, C.L.; Stodolsky, F.; Hanson, D.A.

    1990-08-01

    This report presents estimates of monthly sulfur dioxide (SO{sub 2}), nitrogen oxides (NO{sub x}), and nonmethane voltatile organic compound (VOC) emissions by sector, region, and state in the contiguous United States for the years 1975 through 1988. This work has been funded as part of the National Acid Precipitation Assessment Program`s Emissions and Controls Task Group by the US Department of Energy (DOE) Office of Fossil Energy (FE). The DOE project officer is Edward C. Trexler, DOE/FE Office of Planning and Environment.

  6. Characterization of semi-volatile organic compounds emitted during heating of nitrogen-containing plastics at low temperature.

    PubMed

    Watanabe, Mafumi; Nakata, Chisto; Wu, Wei; Kawamoto, Katsuya; Noma, Yukio

    2007-08-01

    Because of recent volume increases, appropriate management of plastic recycling, which generates various organic compounds, is required to ensure the chemical safety of the processes. The processing temperature and resin type are the important factors determining both the efficiency of the processes and the emission of chemicals. Therefore, we studied the thermal degradation of various plastics at various temperatures from 70 to 300 degrees C under oxygen-present conditions to identify the semi-volatile organic compounds (SVOCs) emitted and to understand their thermal behaviors. The plastics examined were nitrogen-containing resins, such as polyamide 6, polyurethane, melamine formaldehyde, urea formaldehyde and acrylonitrile-butadiene-styrene. Major commodity plastics were also investigated for comparison. In total, more than 500 SVOCs were detected as emissions from plastics. While various nitrogen-containing SVOCs were detected from nitrogen-containing resins, the major commodity plastics released only these, which possibly were included as additives. These results indicate that the nitrogen atoms in the SVOCs emitted originated from the resins and additives, and not from ambient air at low temperature. As a result of the detection of raw materials, degradation chemicals and by-products of the polymers in the emissions, we found that the variation in chemical species is dependent on the resins. Additives were also emitted from all the resins, meaning that these chemicals were also released to the environment at the temperature examined. In most cases, the numbers and concentrations of SVOCs increased with increasing heating temperature. The variation of thermal behaviors of SVOCs was related to the origins and chemical species of SVOCs.

  7. Nitrogen-containing organic compounds: Origins, toxicity and conditions of their photocatalytic mineralization over TiO2.

    PubMed

    Bamba, Drissa; Coulibaly, Mariame; Robert, Didier

    2017-02-15

    Sustainable water management remains a global concern to meet the food needs of industrial and agricultural activities. Therefore, pollution abatement techniques, cheap and environmentally, are highly desired and recommended. The present review is devoted to the origin and the toxicity of nitrogen-containing organic compounds in water. The progress made in removing these pollutants, in recent years, is addressed. However, a prominent place is given to the photocatalytic degradation process using the TiO2 as a semiconductor, the conditions for good mineralization and especially the factors influencing it. The parameters that impact the performance of this method are the pH, the temperature, the reactor used, the light, the concentration of the pollutant, the amount of catalyst, etc. Up to now, the importance of one parameter relative to another has not been established because in the context of the photocatalytic degradation, certain parameters are often tightly coupled. Consequently, the mineralization is dependent on the initial degree of oxidation of nitrogen atom contained in the pollutant to be degraded. The hydroxyl nitrogen is primarily converted into nitrate ions (NO3(-)), while the amides and the primary amines are converted into ammonium ions (NH4(+)).

  8. Volatile organic compounds released from Microcystis flos-aquae under nitrogen sources and their toxic effects on Chlorella vulgaris.

    PubMed

    Xu, Qinghuan; Yang, Lin; Yang, Wangting; Bai, Yan; Hou, Ping; Zhao, Jingxian; Zhou, Lv; Zuo, Zhaojiang

    2017-01-01

    Eutrophication promotes massive growth of cyanobacteria and algal blooms, which can poison other algae and reduce biodiversity. To investigate the differences in multiple nitrogen (N) sources in eutrophicated water on the emission of volatile organic compounds (VOCs) from cyanobacteria, and their toxic effects on other algal growth, we analyzed VOCs emitted from Microcystis flos-aquae with different types and concentrations of nitrogen, and determined the effects under Normal-N and Non-N conditions on Chlorella vulgaris. M. flos-aquae released 27, 22, 20, 27, 19, 25 and 17 compounds, respectively, with NaNO3, NaNO2, NH4Cl, urea, Ser, Lys and Arg as the sole N source. With the reduction in N amount, the emission of VOCs was increased markedly, and the most VOCs were found under Non-N condition. C. vulgaris cell propagation, photosynthetic pigment and Fv/Fm declined significantly following exposure to M. flos-aquae VOCs under Non-N condition, but not under Normal-N condition. When C. vulgaris cells were treated with two terpenoids, eucalyptol and limonene, the inhibitory effects were enhanced with increasing concentrations. Therefore, multiple N sources in eutrophicated water induce different VOC emissions from cyanobacteria, and reduction in N can cause nutrient competition, which can result in emissions of more VOCs. Those VOCs released from M. flos-aquae cells under Non-N for nutrient competition can inhibit other algal growth. Among those VOCs, eucalyptol and limonene are the major toxic agents.

  9. Effect of nitrogen supply and defoliation on loss of organic compounds from roots of Festuca rubra.

    PubMed

    Paterson, E; Sim, A

    2000-08-01

    The aim of this study was to determine the effects of N-supply and defoliation on rhizodeposition from Festuca rubra, in the context of whole-plant C- partitioning and root morphology. Plants were grown for 36 d in axenic sand microcosms continuously percolated with nutrient solutions of either high or low N concentration (2 mM or 0.01 mM NH(4)NO(3), respectively). The effects of partial defoliation at weekly intervals were determined at high and low N. At low N, dry matter accumulation in roots and shoots was reduced significantly (P<0.001), with proportionately increased partitioning to roots, in comparison with the high N treatment. Root morphology was also affected by N-treatment; at low N, lower biomass production was offset by increased specific root length (P<0.001), reducing the magnitude of the significant (P=0.002) increase in total root length at high N. Cumulative release of organic C from roots of F: rubra over the experimental period was not altered significantly by N-treatment. However, as a proportion of net C-assimilation, rhizodeposition was significantly (P<0.001) greater at low N than at high N. Defoliation transiently (3-5 d) increased the release of soluble organic compounds from roots at each N-supply rate, and increased significantly (P<0.001) cumulative rhizodeposition over the experimental period. These effects of N-supply and defoliation on rhizodeposition are of importance in understanding interactions between plant and microbial productivity in grazed grasslands, and in interpretation of concurrent effects on microbially driven nutrient cycling processes in these systems.

  10. Development of a NIST standard reference material containing thirty volatile organic compounds at 5 nmol/mol in nitrogen.

    PubMed

    Rhoderick, George C; Yen, James H

    2006-05-01

    Primary gravimetric gas cylinder standards containing 30 volatile organic compounds (VOCs) in nitrogen were prepared using a procedure previously developed to prepare gas mixture cylinder standards of VOCs at the 5 nmol/mol level. This set of primary standards was intercompared to existing gas cylinder standards, containing as many as 19 of the 30 volatile organics present in these new primaries, using gas chromatography with a hydrogen flame ionization detector coupled with cryogenic preconcentration. The linear regression analysis showed excellent agreement among the standards for each compound. Similar mixtures containing many of these compounds in treated aluminum gas cylinders have been evaluated over time and have shown stability for as much as 10 years. The development of these 30-component primary standards led to the preparation and certification of a reissue of Standard Reference Material (SRM) 1804 at the nominal amount-of-substance fraction of 5 nmol/mol for each analyte. A lot of 20 cylinders containing the mixture was prepared at NIST following previously demonstrated protocols for preparation of the cylinders. Each cylinder was analyzed against one cylinder from the lot, designated as the "lot standard," for each of the 30 compounds. As a result of the uncertainty analysis, the data showed that rather than declaring the lot homogeneous with a much higher uncertainty, each cylinder could be individually certified. The expanded uncertainty limits ranged from 1.5 to 10% for 28 of the 30 analytes, with two of the analytes having uncertainties as high as 19% in those SRM cylinders certified. Due to stability issues and some high uncertainties for a few analytes in 2 of the samples, 18 of the 20 candidate SRM samples were certified. These volatile organic gas mixtures represent the most complex gas SRMs developed at NIST.

  11. Formation of nitrogen- and sulfur-containing light-absorbing compounds accelerated by evaporation of water from secondary organic aerosols

    NASA Astrophysics Data System (ADS)

    Nguyen, Tran B.; Lee, Paula B.; Updyke, Katelyn M.; Bones, David L.; Laskin, Julia; Laskin, Alexander; Nizkorodov, Sergey A.

    2012-01-01

    Aqueous extracts of secondary organic aerosols (SOA) generated from the ozonolysis of d-limonene were subjected to dissolution, evaporation, and re-dissolution in the presence and absence of ammonium sulfate (AS). Evaporation with AS at pH 4-9 produced chromophores that were stable with respect to hydrolysis and had a distinctive absorption band at 500 nm. Evaporation accelerated the rate of chromophore formation by at least three orders of magnitude compared to the reaction in aqueous solution, which produced similar compounds. Absorption spectroscopy and high-resolution nanospray desorption electrospray ionization (nano-DESI) mass spectrometry experiments suggested that the molar fraction of the chromophores was small (<2%), and that they contained nitrogen atoms. Although the colored products represented only a small fraction of SOA, their large extinction coefficients (>105 L mol-1 cm-1 at 500 nm) increased the effective mass absorption coefficient of the residual organics in excess of 103 cm2 g-1 - a dramatic effect on the optical properties from minor constituents. Evaporation of SOA extracts in the absence of AS resulted in the production of colored compounds only when the SOA extract was acidified to pH ˜ 2 with sulfuric acid. These chromophores were produced by acid-catalyzed aldol condensation, followed by a conversion into organosulfates. The presence of organosulfates was confirmed by high resolution mass spectrometry experiments. Results of this study suggest that evaporation of cloud or fog droplets containing dissolved organics leads to significant modification of the molecular composition and serves as a potentially important source of light-absorbing compounds.

  12. Formation of Nitrogen- and Sulfur-Containing Light-Absorbing Compounds Accelerated by Evaporation of Water from Secondary Organic Aerosols

    SciTech Connect

    Nguyen, Tran B.; Lee, Paula B.; Updyke, Katelyn M.; Bones, David L.; Laskin, Julia; Laskin, Alexander; Nizkorodov, Sergey

    2012-01-14

    Aqueous extracts of secondary organic aerosols (SOA) generated from the ozonolysis of dlimonene were subjected to dissolution, evaporation, and re-dissolution in the presence and absence of ammonium sulfate (AS). Evaporation with AS at pH 4-9 produced chromophores that were stable with respect to hydrolysis and had a distinctive absorption band at 500 nm. Evaporation accelerated the rate of chromophore formation by at least three orders of magnitude compared to the reaction in aqueous solution, which produced similar compounds. Absorption spectroscopy and high-resolution nanospray desorption electrospray ionization (nano-DESI) mass spectrometry experiments suggested that the molar fraction of the chromophores was small (< 2%), and that they contained nitrogen atoms. Although the colored products represented only a small fraction of SOA, their large extinction coefficients (>10{sup 5} L mol{sup -1} cm{sup -1} at 500 nm) increased the effective mass absorption coefficient of the residual organics in excess of 10{sup 3} cm{sup 2} g{sup -1} - a dramatic effect on the optical properties from minor constituents. Evaporation of SOA extracts in the absence of AS resulted in the production of colored compounds only when the SOA extract was acidified to pH {approx} 2 with sulfuric acid. These chromophores were produced by acid-catalyzed aldol condensation, followed by a conversion into organosulfates. The presence of organosulfates was confirmed by high resolution mass spectrometry experiments. Results of this study suggest that evaporation of cloud or fog droplets containing dissolved organics leads to significant modification of the molecular composition and serves as a potentially important source of light-absorbing compounds.

  13. NATURAL EMISSIONS OF NON-METHANE VOLATILE ORGANIC COMPOUNDS, CARBON MONOXIDE, AND OXIDES OF NITROGEN FROM NORTH AMERICA

    EPA Science Inventory

    The magnitudes, distributions, controlling processes and uncertainties associated with North American natural emissions of oxidant precursors are reviewed. Natural emissions are repsonsible for a major portion of the compounds, including non-methane volatile organic compounds (N...

  14. Emissions of nitrogen-containing organic compounds from the burning of herbaceous and arboraceous biomass: Fuel composition dependence and the variability of commonly used nitrile tracers

    NASA Astrophysics Data System (ADS)

    Coggon, Matthew M.; Veres, Patrick R.; Yuan, Bin; Koss, Abigail; Warneke, Carsten; Gilman, Jessica B.; Lerner, Brian M.; Peischl, Jeff; Aikin, Kenneth C.; Stockwell, Chelsea E.; Hatch, Lindsay E.; Ryerson, Thomas B.; Roberts, James M.; Yokelson, Robert J.; Gouw, Joost A.

    2016-09-01

    Volatile organic compounds (VOCs) emitted from residential wood and crop residue burning were measured in Colorado, U.S. When compared to the emissions from crop burning, residential wood burning exhibited markedly lower concentrations of acetonitrile, a commonly used biomass burning tracer. For both herbaceous and arboraceous fuels, the emissions of nitrogen-containing VOCs (NVOCs) strongly depend on the fuel nitrogen content; therefore, low NVOC emissions from residential wood burning result from the combustion of low-nitrogen fuel. Consequently, the emissions of compounds hazardous to human health, such as HNCO and HCN, and the formation of secondary pollutants, such as ozone generated by NOx, are likely to depend on fuel nitrogen. These results also demonstrate that acetonitrile may not be a suitable tracer for domestic burning in urban areas. Wood burning emissions may be best identified through analysis of the emissions profile rather than reliance on a single tracer species.

  15. Seasonal variation of nitrogen oxides, ozone and biogenic volatile organic compound concentrations and fluxes at Norway spruce forest

    NASA Astrophysics Data System (ADS)

    Juran, Stanislav; Vecerova, Kristyna; Holisova, Petra; Zapletal, Milos; Pallozzi, Emanuele; Guidolotti, Gabriele; Calfapietra, Carlo; Vecera, Zbynek; Cudlin, Pavel; Urban, Otmar

    2015-04-01

    Dynamics of nitrogen oxides (NOx) and ozone concentration and their depositions were investigated on the Norway spruce forest at Bily Kriz experimental station at the Silesian Beskydy Mountains (north-eastern part of the Czech Republic). Both NOx and ozone concentration and fluxes were modelled for the whole season and covering thus different climate conditions. Data were recorded for three consecutive years and therefore deeper analyses were performed. During the summer 2014 BVOC field campaign was carried out using proton-transfer-reaction-time-of-flight-mass-spectrometry (PTR-TOF, Ionicon Analytik GmbH, Innsbruck, Austria) and volatile organic compound of biogenic origin (BVOC) were measured at the different levels of tree canopies. By the same time BVOC were trapped into the Tenax tubes (Markes International Ltd., UK) and put afterwards for thermal desorption (Markes Unity System 2, Markes International Ltd., UK) to GS-MS analysis (TSQ Quntum XLS triple Quadrupole, Thermo Scientific, USA). Thus data of different levels of canopies together with different spectra of monoterpenes were obtained. Interesting comparison of both methods will be shown. It was the first BVOC field campaign using PTR technique at any of the forest in the Czech Republic. Highest fluxes and concentrations were recorded around the noon hours, represented particularly by monoterpenes, especially α-pinen and limonene. Other BVOCs than monoterpenes were negligible. Variation of fluxes between different canopies levels was observed, highlighting difference in shaded and sun exposed leaves. Sun leaves emitted up to 2.4 nmol m-2 s-1 of monoterpenes, while shaded leaves emitted only up to 0.6 nmol m-2 s-1 when measured under standard conditions (irradiance 1000 µmol m-2 s-1; temperature 30°C). We discuss here the importance of the most common Norway spruce tree forests in the Czech Republic in bi-directional exchanges of important secondary pollutant such as ozone and nitrogen oxides, their

  16. Assessing traffic and industrial contributions to ambient nitrogen dioxide and volatile organic compounds in a low pollution urban environment.

    PubMed

    Oiamo, Tor H; Johnson, Markey; Tang, Kathy; Luginaah, Isaac N

    2015-10-01

    Land use regression (LUR) modeling is an effective method for estimating fine-scale distributions of ambient air pollutants. The objectives of this study are to advance the methodology for use in urban environments with relatively low levels of industrial activity and provide exposure assessments for research on health effects of air pollution. Intraurban distributions of nitrogen dioxide (NO2) and the volatile organic compounds (VOCs) benzene, toluene and m- and p-xylene were characterized based on spatial monitoring and LUR modeling in Ottawa, Ontario, Canada. Passive samplers were deployed at 50 locations throughout Ottawa for two consecutive weeks in October 2008 and May 2009. Land use variables representing point, area and line sources were tested as predictors of pooled pollutant distributions. LUR models explained 96% of the spatial variability in NO2 and 75-79% of the variability in the VOC species. Proximity to highways, green space, industrial and residential land uses were significant in the final models. More notably, proximity to industrial point sources and road network intersections were significant predictors for all pollutants. The strong contribution of industrial point sources to VOC distributions in Ottawa suggests that facility emission data should be considered whenever possible. The study also suggests that proximity to road network intersections may be an effective proxy in areas where reliable traffic data are not available.

  17. Surface and boundary layer exchanges of volatile organic compounds, nitrogen oxides and ozone during the GABRIEL campaign

    NASA Astrophysics Data System (ADS)

    Ganzeveld, L.; Eerdekens, G.; Feig, G.; Fischer, H.; Harder, H.; Königstedt, R.; Kubistin, D.; Martinez, M.; Meixner, F. X.; Scheeren, H. A.; Sinha, V.; Taraborrelli, D.; Williams, J.; Vilöguerau de Arellano, J.; Lelieveld, J.

    2008-10-01

    We present an evaluation of sources, sinks and turbulent transport of nitrogen oxides, ozone and volatile organic compounds (VOC) in the boundary layer over French Guyana and Suriname during the October 2005 GABRIEL campaign by simulating observations with a single-column chemistry and climate model (SCM) along a zonal transect. Simulated concentrations of O3 and NO as well as NO2 photolysis rates over the forest agree well with observations when a small soil-biogenic NO emission flux was applied. This suggests that the photochemical conditions observed during GABRIEL reflect a pristine tropical low-NOx regime. The SCM uses a compensation point approach to simulate nocturnal deposition and daytime emissions of acetone and methanol and produces daytime boundary layer mixing ratios in reasonable agreement with observations. The area average isoprene emission flux, inferred from the observed isoprene mixing ratios and boundary layer height, is about half the flux simulated with commonly applied emission algorithms. The SCM nevertheless simulates too high isoprene mixing ratios, whereas hydroxyl concentrations are strongly underestimated compared to observations, which can at least partly explain the discrepancy. Furthermore, the model substantially overestimates the isoprene oxidation products methlyl vinyl ketone (MVK) and methacrolein (MACR) partly due to a simulated nocturnal increase due to isoprene oxidation. This increase is most prominent in the residual layer whereas in the nocturnal inversion layer we simulate a decrease in MVK and MACR mixing ratios, assuming efficient removal of MVK and MACR. Entrainment of residual layer air masses, which are enhanced in MVK and MACR and other isoprene oxidation products, into the growing boundary layer poses an additional sink for OH which is thus not available for isoprene oxidation. Based on these findings, we suggest pursuing measurements of the tropical residual layer chemistry with a focus on the nocturnal depletion

  18. Surface and boundary layer exchanges of volatile organic compounds, nitrogen oxides and ozone during the GABRIEL Campaign

    NASA Astrophysics Data System (ADS)

    Ganzeveld, L.; Eerdekens, G.; Feig, G.; Fischer, H.; Harder, H.; Königstedt, R.; Kubistin, D.; Martinez, M.; Meixner, F. X.; Scheeren, B.; Sinha, V.; Taraborrelli, D.; Williams, J.; Vilöguerau de Arellano, J.; Lelieveld, J.

    2008-06-01

    We present an evaluation of sources, sinks and turbulent transport of nitrogen oxides, ozone and volatile organic compounds (VOC) in the boundary layer over French Guyana and Suriname during the October 2005 GABRIEL campaign by simulating observations with a single-column chemistry and climate model (SCM) along a zonal transect. Simulated concentrations of O3 and NO as well as NO2 photolysis rates over the forest agree well with observations when a small soil-biogenic NO emission flux was applied. This suggests that the photochemical conditions observed during GABRIEL reflect a pristine tropical low-NOx regime. The SCM uses a compensation point approach to simulate nocturnal deposition and daytime emissions of acetone and methanol and produces daytime boundary layer mixing ratios in reasonable agreement with observations. The area average isoprene emission flux, inferred from the observed isoprene mixing ratios and boundary layer height, is about half the flux simulated with commonly applied emission algorithms. The SCM nevertheless simulates too high isoprene mixing ratios, whereas hydroxyl concentrations are strongly underestimated compared to observations, which can at least partly explain the discrepancy. Furthermore, the model substantially overestimates the isoprene oxidation products methlyl vinyl ketone (MVK) and methacrolein (MACR) partly due to a simulated nocturnal increase due to isoprene oxidation. This increase is most prominent in the residual layer whereas in the nocturnal inversion layer we simulate a decrease in MVK and MACR mixing ratios, assuming efficient removal of MVK and MACR. Entrainment of residual layer air masses, which are enhanced in MVK and MACR and other isoprene oxidation products, into the growing boundary layer poses an additional sink for OH which is thus not available for isoprene oxidation. Based on these findings, we suggest pursuing measurements of the tropical residual layer chemistry with a focus on the nocturnal depletion

  19. Aqueous phase removal of nitrogen from nitrogen compounds

    DOEpatents

    Fassbender, Alex G.

    1993-01-01

    A method is disclosed for denitrification of compounds containing nitrogen present in aqueous waste streams. The method comprises the steps of (1) identifying the types of nitrogen compounds present in a waste stream, (2) determining the concentrations of nitrogen compounds, (3) balancing oxidized and reduced form of nitrogen by adding a reactant, and (4) heating the mixture to a predetermined reaction temperature from about 300.degree. C. to about 600.degree. C., thereby resulting in less harmful nitrogen and oxygen gas, hydroxides, alcohols, and hydrocarbons.

  20. Synthesis of adenine, guanine, cytosine, and other nitrogen organic compounds by a Fischer-Tropsch-like process.

    NASA Technical Reports Server (NTRS)

    Yang, C. C.; Oro, J.

    1971-01-01

    Study of the formation of purines, pyrimidines, and other bases from CO, H2, and NH3 under conditions similar to those used in the Fischer-Tropsch process. It is found that industrial nickel/iron alloy catalyzes the synthesis of adenine, guanine, cytosine, and other nitrogenous compounds from mixtures of CO, H2, and NH3 at temperatures of about 600 C. Sufficient sample was accumulated to isolate as solid products adenine, guanine, and cytosine, which were identified by infrared spectrophotometry. In the absence of nickel/iron catalyst, at 650 C, or in the presence of this catalyst, at 450 C, no purines or pyrimidines were synthesized. These results confirm and extend some of the work reported by Kayatsu et al. (1968).

  1. Characterization of organic nitrogen in IBCSP coals

    SciTech Connect

    Kruge, M.A.

    1991-01-01

    The overall objective of this study was to determine the content and distribution of organic nitrogen in a series of IBCSP coals and their isolated macerals. The specific objectives were: to determine the bulk nitrogen contents for coals, isolated macerals, oxidation products and residues, solvent extracts and their liquid chromatographic fractions, and pyrolyzates; to determine the distribution of organic nitrogen in all coal derivatives enumerated in Objective 1 which are Gas Chromatography (GC)-amenable. This will be accomplished by GC-Thermionic Specific Detectors; to determine the molecular structure of the major nitrogen compounds detected in Objective 2, using mass spectrometry.

  2. Aerosol from Organic Nitrogen in the Southeast United States

    EPA Science Inventory

    Biogenic volatile organic compounds (BVOCs) contribute significantly to organic aerosol in the southeastern United States. During the Southern Oxidant and Aerosol Study (SOAS), a portion of ambient organic aerosol was attributed to isoprene oxidation and organic nitrogen from BVO...

  3. Extraterrestrial Organic Compounds in Meteorites

    NASA Technical Reports Server (NTRS)

    Botta, Oliver; Bada, Jeffrey L.; Meyer, Michael (Technical Monitor)

    2003-01-01

    Many organic compounds or their precursors found in meteorites originated in the interstellar or circumstellar medium and were later incorporated into planetesimals during the formation of the solar system. There they either survived intact or underwent further processing to synthesize secondary products on the meteorite parent body. The most distinct feature of CI and CM carbonaceous chondrites, two types of stony meteorites, is their high carbon content (up to 3% of weight), either in the form of carbonates or of organic compounds. The bulk of the organic carbon consists of an insoluble macromolecular material with a complex structure. Also present is a soluble organic fraction, which has been analyzed by several separation and analytical procedures. Low detection limits can be achieved by derivatization of the organic molecules with reagents that allow for analysis by gas chromatography/mass spectroscopy and high performance liquid chromatography. The CM meteorite Murchison has been found to contain more than 70 extraterrestrial amino acids and several other classes of compounds including carboxylic acids, hydroxy carboxylic acids, sulphonic and phosphonic acids, aliphatic, aromatic and polar hydrocarbons, fullerenes, heterocycles as well as carbonyl compounds, alcohols, amines and amides. The organic matter was found to be enriched in deuterium, and distinct organic compounds show isotopic enrichments of carbon and nitrogen relative to terrestrial matter.

  4. Influence of olive (cv Grignano) fruit ripening and oil extraction under different nitrogen regimes on volatile organic compound emissions studied by PTR-MS technique.

    PubMed

    Vezzaro, Alice; Boschetti, Andrea; Dell'Anna, Rossana; Canteri, Roberto; Dimauro, Mariano; Ramina, Angelo; Ferasin, Massimo; Giulivo, Claudio; Ruperti, Benedetto

    2011-03-01

    Volatile organic compounds of extra virgin olive oils obtained from the local Italian cultivar Grignano were measured by proton transfer reaction-mass spectrometry (PTR-MS). Oils were extracted by olives harvested at different ripening stages across veraison, performing each extraction step and the whole extraction process in nitrogen atmosphere to observe the changes in the volatile profiles of the oils. Principal component analysis carried out on the full spectral signature of the PTR-MS measurements showed that the stage of ripening has a stronger effect on the global definition of volatile profiles than the use of nitrogen during oil extraction. The fingerprint-like chemical information provided by the spectra were used to construct a heat map, which allowed the dynamical representation of the multivariate nature of mass evolution during the ripening process. This provided the first evidence that some groups of volatile organic compounds displayed a time course of regulation with coordinated increasing or decreasing trends in association with specific stages of fruit ripening.

  5. Volatile Organic Compounds (VOCs)

    MedlinePlus

    ... United States Environmental Protection Agency Search Search Indoor Air Quality (IAQ) Share Facebook Twitter Google+ Pinterest Contact Us Volatile Organic Compounds' Impact on Indoor Air Quality On this page: Introduction Sources Health Effects Levels ...

  6. Determination of chemical oxygen demand of nitrogenous organic compounds in wastewater using synergetic photoelectrocatalytic oxidation effect at TiO2 nanostructured electrode.

    PubMed

    Li, Lihong; Zhang, Shanqing; Li, Guiying; Zhao, Huijun

    2012-11-19

    Chemical oxygen demand (COD) is one of the most important parameters in water quality assessment and monitoring. The natural degradation of nitrogenous organic compounds (NOCs) in water requires significant amounts of oxygen. In the determination of standard COD however, NOCs are persistent compounds that cannot be completely oxidized even in the most oxidative chemical environments, i.e. the reaction media that contain high concentrations of dichromate in strong acid at high temperature. Consequently, the measured COD values of wastewater samples containing NOCs are commonly lower than theoretical COD values and do not reflect the actual oxygen demand of the water body. This problem is partially alleviated when the photoelectrochemical method for COD determination (PeCOD) based on nanostructured TiO(2) photoanode is utilized. To completely overcome this problem, a synergetic photoelectrochemical oxidation effect in thin layer cells is used to achieve complete oxidation of NOCs. This is done by the simple addition of a hydroxyl organic compound (i.e. glucose) into the test sample before the PeCOD measurement. Preliminary experimental results demonstrate that the synergetic PeCOD method provides an effective and reliable means to measure COD values of NOC-containing pollutants without the need for toxic or expensive reagents.

  7. Fluoroalkylation of organic compounds

    NASA Astrophysics Data System (ADS)

    Mikhaylov, D. Yu; Budnikova, Yu H.

    2013-09-01

    Data on fluoroalkylation and perfluoroalkylation methods in organic synthesis are analyzed, summarized and described systematically. The most practically important properties of compounds with fluoroalkyl substituents are illustrated. The key trends and the potential of this field of organic chemistry are considered. Electrochemical syntheses of perfluoroalkyl derivatives that are inaccessible or experimentally difficult to prepare by regular chemical techniques are presented. Particular attention is paid to processes involving organometallic compounds as well as to prospects for the development of this field of research. The bibliography includes 226 references.

  8. Organic compounds in meteorites

    NASA Technical Reports Server (NTRS)

    Anders, E.; Hayatsu, R.; Studier, M. H.

    1973-01-01

    The problem of whether organic compounds originated in meteorites as a primary condensate from a solar gas or whether they were introduced as a secondary product into the meteorite during its residence in a parent body is examined by initially attempting to reconstruct the physical conditions during condensation (temperature, pressure, time) from clues in the inorganic matrix of the meteorite. The condensation behavior of carbon under these conditions is then analyzed on the basis of thermodynamic calculations, and compounds synthesized in model experiments on the condensation of carbon are compared with those actually found in meteorites. Organic compounds in meteorites seem to have formed by catalytic reactions of carbon monoxide, hydrogen, and ammonia in the solar nebula at 360 to 400 K temperature and about 3 to 7.6 microtorr pressure. The onset of these reactions was triggered by the formation of suitable catalysts (magnetite, hydrated silicates) at these temperatures.

  9. NATURAL EMISSIONS OF NON-METHANE VOLATILE ORGANIC COMPOUNDS, CARBON MONOXIDE, AND OXIDES OF NITROGEN FROM NORTH AMERICA. (R825259)

    EPA Science Inventory

    Abstract

    The magnitudes, distributions, controlling processes and uncertainties associated with North American natural emissions of oxidant precursors are reviewed. Natural emissions are responsible for a major portion of the compounds, including non-methane volatile o...

  10. Ambient air levels of volatile organic compounds (VOC) and nitrogen dioxide (NO2) in a medium size city in Northern Spain.

    PubMed

    Parra, M A; Elustondo, D; Bermejo, R; Santamaría, J M

    2009-01-15

    Ambient concentrations of volatile organic compounds (VOC) and nitrogen dioxide (NO2) were measured by means of passive sampling at 40 sampling points in a medium-size city in Northern Spain, from June 2006 to June 2007. VOC and NO2 samplers were analysed by thermal desorption followed by gas chromatography/mass-selective detector and by visible spectrophotometry, respectively. Mean concentrations of benzene, toluene, ethylbenzene, xylenes, propylbenzene, trimethylbenzenes, and NO(2) were 2.84, 13.26, 2.15, 6.01, 0.59, 1.32 and 23.17 microg m(-3) respectively, and found to be highly correlated. Their spatial distribution showed high differences in small distances and pointed to traffic as the main emission source of these compounds. The lowest levels of VOC and NO2 occurred during summer, owing to the increase in solar radiation and to lower traffic densities. Mean concentrations of benzene and NO2 exceeded the European limits at some of the monitored points.

  11. Response of fine particulate matter to emission changes of oxides of nitrogen and anthropogenic volatile organic compounds in the eastern United States

    SciTech Connect

    Alexandra P. Tsimpidi; Vlassis A. Karydis; Spyros N. Pandis

    2008-11-15

    A three-dimensional chemical transport model (Particulate Matter Comprehensive Air Quality Model with Extensions) is used to investigate changes in fine particle (PM2.5) concentrations in response to 50% emissions changes of oxides of nitrogen (NOx) and anthropogenic volatile organic compounds (VOCs) during July 2001 and January 2002 in the eastern United States. The reduction of NOx emissions by 50% during the summer results in lower average oxidant levels and lowers PM2.5 (8% on average), mainly because of reductions of sulfate (9-11%), nitrate (45-58%), and ammonium (7-11%). The organic particulate matter (PM) slightly decreases in rural areas, whereas it increases in cities by a few percent when NOx is reduced. Reduction of NOx during winter causes an increase of the oxidant levels and a rather complicated response of the PM components, leading to small net changes. Sulfate increases (8-17%), nitrate decreases (18-42%), organic PM slightly increases, and ammonium either increases or decreases a little. The reduction of VOC emissions during the summer causes on average a small increase of the oxidant levels and a marginal increase in PM2.5. This small net change is due to increases in the inorganic components and decreases of the organic ones. Reduction of VOC emissions during winter results in a decrease of the oxidant levels and a 5-10% reduction of PM2.5 because of reductions in nitrate (4-19%), ammonium (4-10%), organic PM (12-14%), and small reductions in sulfate. Although sulfur dioxide (SO{sub 2}) reduction is the single most effective approach for sulfate control, the coupled decrease of SO{sub 2} and NOx emissions in both seasons is more effective in reducing total PM2.5 mass than the SO{sub 2} reduction alone. 34 refs., 7 figs., 1 tab.

  12. Governing processes for reactive nitrogen compounds in the European atmosphere

    NASA Astrophysics Data System (ADS)

    Hertel, O.; Skjøth, C. A.; Reis, S.; Bleeker, A.; Harrison, R. M.; Cape, J. N.; Fowler, D.; Skiba, U.; Simpson, D.; Jickells, T.; Kulmala, M.; Gyldenkærne, S.; Sørensen, L. L.; Erisman, J. W.; Sutton, M. A.

    2012-12-01

    Reactive nitrogen (Nr) compounds have different fates in the atmosphere due to differences in the governing processes of physical transport, deposition and chemical transformation. Nr compounds addressed here include reduced nitrogen (NHx: ammonia (NH3) and its reaction product ammonium (NH4+)), oxidized nitrogen (NOy: nitrogen monoxide (NO) + nitrogen dioxide (NO2) and their reaction products) as well as organic nitrogen compounds (organic N). Pollution abatement strategies need to take into account the differences in the governing processes of these compounds when assessing their impact on ecosystem services, biodiversity, human health and climate. NOx (NO + NO2) emitted from traffic affects human health in urban areas where the presence of buildings increases the residence time in streets. In urban areas this leads to enhanced exposure of the population to NOx concentrations. NOx emissions generally have little impact on nearby ecosystems because of the small dry deposition rates of NOx. These compounds need to be converted into nitric acid (HNO3) before removal through deposition is efficient. HNO3 sticks quickly to any surface and is thereby either dry deposited or incorporated into aerosols as nitrate (NO3-). In contrast to NOx compounds, NH3 has potentially high impacts on ecosystems near the main agricultural sources of NH3 because of its large ground-level concentrations along with large dry deposition rates. Aerosol phase NH4+ and NO3- contribute significantly to background PM2.5 and PM10 (mass of aerosols with an aerodynamic diameter of less than 2.5 and 10 μm, respectively) with an impact on radiation balance as well as potentially on human health. Little is known quantitatively and qualitatively about organic N in the atmosphere, other than that it contributes a significant fraction of wet-deposited N, and is present in both gaseous and particulate forms. Further studies are needed to characterise the sources, air chemistry and

  13. Approaches to Determining the Oxidation State of Nitrogen and Carbon Atoms in Organic Compounds for High School Students

    ERIC Educational Resources Information Center

    Jurowski, Kamil; Krzeczkowska, Malgorzata Krystyna; Jurowska, Anna

    2015-01-01

    The concept of oxidation state (or oxidation number) and related issues have always been difficult for students. In addition, there are misunderstandings and obscurities, which can cause improper balancing of the chemical equations (mostly in organic reactions). In particular, these problems are related to determination of the oxidation state of…

  14. Prebiotic Evolution of Nitrogen Compounds

    NASA Technical Reports Server (NTRS)

    Arrhenius, G.

    1999-01-01

    Support from this four year grant has funded our research on two general problems. One involves attempts to model the abiotic formation of simple source compounds for functional biomolecules, their concentration from dilute state in the hydrosphere and, in several cases, surface induced reactions to form precursor monomers for bioactive end products (refs. 1-5). Because of the pervasiveness and antiquity of phosphate based biochemistry and the catalytic activity of RNA we have exploring the hypothesis of an RNA World as an early stage in the emergence of life. This concept is now rather generally considered, but has been questioned due to the earlier lack of an experimentally demonstrated successful scheme for the spontaneous formation of ribose phosphate, the key backbone molecule in RNA. That impediment has now been removed. This has been achieved by demonstrating probable sources of activated (condensed) highly soluble and strongly sorbed phosphates in nature (Refs. 1,2) and effective condensation of aldehyde phosphates to form ribose phosphate in high yield (ref.6), thereby placing the RNA World concept on a somewhat safer experimental footing. Like all work in this field these experiments are oversimplifications that largely ignore competing side reactions with other compounds expected to be present. None the less our choice of experimental conditions aim at selective processes that eliminate interfering reactions. We have also sought to narrow the credibility gap by simulating geophysically and geochemically plausible conditions surrounding the putative prebiotic reactions.

  15. Nitrogen compounds in Titan's stratosphere

    NASA Astrophysics Data System (ADS)

    Coustenis, A.; Cirs Investigation Team

    Titan's atmosphere is essentially composed of molecular nitrogen (N2). The chemistry between the two mother molecules (N2 and CH4) leads to the formation of a certain number of nitriles observed in Titan's stratosphere as early as at the time of the Voyager 1 encounter in 1980. In the spectra taken by the Infrared Radiometer Interferometer Spectrometer (IRIS) the signatures of HCN, HC3N, C2N2 and C4N2 (in solid form) were found and reported. Subsequent observations from the ground better described the vertical profiles of these constituents and allowed for the detection of CH3CN (acetonitrile) in the mm range [3,4]. Recent data recorded by the Composite Infrared Spectrometer (CIRS) aboard the Cassini spacecraft during the Titan flybys (October 2004 - June 2006) give a handle on the temporal and latitudinal variations of these constituents. The nadir spectra characterize various regions on Titan from 85°S to 75°N with a variety of emission angles. We study the emission observed in the mid-infrared CIRS detector arrays (covering roughly the 600-1500 cm-1 spectral range with apodized resolutions of 2.54 or 0.53 cm-1 ). The composite spectrum shows several molecular signatures of nitriles. Information is retrieved on the meridional variations of the trace constituents and tied to predictions by dynamical-photochemical models [1,2,5]. The nitriles show a significant enhancement at high northern latitudes albeit not as marked as at the time of the Voyager encounter. We will give a review of our current understanding of the minor nitrile chemistry on Titan. References : [1] Coustenis et al., 2006. Icarus, in press. [2] Flasar et al., 2005. Science 308, 975. [3] Marten, A., et al., 2002, Icarus, 158, 532-544. [4] Marten, A. & Moreno, R., 2003. 35th Annual DPS Meeting, Monterey, Ca, BAAS, 35, 952. [5] Teanby et al., 2006. Icarus, 181, 243-255.

  16. Comparative study of comprehensive gas chromatography-nitrogen chemiluminescence detection and gas chromatography-ion trap-tandem mass spectrometry for determining nicotine and carcinogen organic nitrogen compounds in thirdhand tobacco smoke.

    PubMed

    Ramírez, Noelia; Vallecillos, Laura; Lewis, Alastair C; Borrull, Francesc; Marcé, Rosa M; Hamilton, Jacqueline F

    2015-12-24

    Thirdhand tobacco smoke (THS) constitutes a poorly understood pathway of exposure of non-smokers, especially toddlers, to tobacco-related carcinogens. However, to date most of the carcinogens present in tobacco smoke have not been detected in THS and, therefore, the significance of THS health risk is still unknown. In this study, we have compared the performance of two analytical methods - one based on gas chromatography coupled to ion trap mass spectrometry detection (GC-IT-MS) and the other on comprehensive two-dimensional gas chromatography coupled to a nitrogen chemiluminescence detector (GC×GC-NCD) - for simultaneously determining, in settled house dust, the presence of 16 organic nitrogen carcinogens already detected in tobacco smoke. The target compounds included four aromatic amines, two nitrocompounds, eight N-nitrosamines and two tobacco-specific nitrosamines, as well as nicotine as a tobacco marker. Dust samples were extracted using in-cell clean up pressurized liquid extraction with silica as clean up sorbent and ethyl acetate as the organic solvent, with average recovery of 89%. Although GC-IT-MS, using chemical ionization with methanol and tandem MS, performed well, the optimized GC×GC-NCD gave lower limits of detection (from 4 to 22ngg(-1)) and better repeatability and reproducibility a low concentration levels (%RSD<8%) and, therefore, was applicable for determining these different groups of carcinogens without the need for derivatization prior to the GC analysis. The performance of the optimized PLE/GC×GC-NCD method was tested by quantifying the target compounds in house dust samples from smokers' and non-smokers' homes. The median carcinogen compounds detected was 3.8μgg(-1) and 1.1μgg(-1) in smokers' and non-smokers' house dust, respectively. In this study, we have detected highly carcinogenic aromatic amines and nitro compounds for the first time in settled house dust complementing the state of knowledge of THS composition and providing

  17. Molybdenum compounds in organic synthesis

    NASA Astrophysics Data System (ADS)

    Khusnutdinov, R. I.; Oshnyakova, T. M.; Dzhemilev, U. M.

    2017-02-01

    The review presents the first analysis and systematic discussion of data published in the last 35–40 years on the use of molybdenum compounds and complexes in organic synthesis and catalysis of various ion coordination and radical reactions. Detailed account is given of the key trends in the use of molybdenum complexes as catalysts of alkene epoxidation and oxyketonation, oxidation of sulfur, nitrogen and phosphorus compounds, hydrosilylation of 1,3-dienes, ketones and aldehydes, hydrostannylation of acetylenes and hydrogermylation of norbornadienes. Considerable attention is paid to the description of new reactions and in situ generation of highly reactive hypohalites, ROX and HOX, induced by molybdenum complexes and the use of hypohalites in oxidative transformations. Data on the application of molybdenum complexes in well-known reactions are discussed, including Kharasch and Pauson–Khand reactions, allylic alkylation of C-nucleophiles, aminocarbonylation of halo derivatives and oligomerization of cyclic dienes, trienes, alkynes and 1,3-dienes. The last Section of the review considers 'unusual' organic reactions involving molybdenum compounds and complexes. The bibliography includes 257 references.

  18. Factors affecting the selectivity of the photocatalytic conversion of nitroaromatic compounds over TiO2 to valuable nitrogen-containing organic compounds.

    PubMed

    Hakki, Amer; Dillert, Ralf; Bahnemann, Detlef W

    2013-02-28

    The photocatalytic conversion of various nitroaromatic compounds in alcohols employing four different types of TiO(2) (Sachtleben Hombikat UV100 as anatase, Crystal Global R34 as rutile, Evonik-Degussa Aeroxide P25 as an anatase-rutile mixture, and home-made mesoporous anatase) has been studied. The effect of platinization of these different types of TiO(2) on the reaction sequence has also been investigated. Upon irradiation of an ethanolic solution of m-nitrotoluene, as a model reaction, in the presence of the bare photocatalyst, different products were obtained according to the applied photocatalyst. It was found that the surface properties of the photocatalyst play an important role in the reaction pathway and thus in the selectivity of the products. In all cases, a simultaneous reduction of the nitro compound and an oxidation of the alcohol are induced by the photogenerated electrons and holes, respectively. An imine is then produced upon condensation of the generated aldehyde and amino compounds. Rutile was found to be more selective towards the primary amino compound (m-toluedine) while anatase catalysts gave a mixture of m-toluidine and its imine (N-ethylidene-3-methylaniline). A cyclization reaction of the produced imine to generate methyl quinoline was observed when Aeroxide P25 was used as a photocatalyst. Employing platinized TiO(2), the hydrogenation of the produced imine yielding N-alkylated products was found to occur in all cases. However, the selectivity towards the mono N-alkylated product was the best using platinized Hombikat UV100. This selectivity was found to be also influenced by the loaded amount of Pt, the platinization method, and the illumination time but not by the light intensity.

  19. Organic compounds in meteorites

    NASA Technical Reports Server (NTRS)

    Lawless, J. G.

    1980-01-01

    Recent studies of carbonaceous chondrites provide evidence that certain organic compounds are indigenous and the result of an abiotic, chemical synthesis. The results of several investigators have established the presence of amino acids and precursors, mono- and dicarboxylic acids, N-heterocycles, and hydrocarbons as well as other compounds. For example, studies of the Murchison and Murray meteorites have revealed the presence of at least 40 amino acids with nearly equal abundances of D and L isomers. The population consists of both protein and nonprotein amino acids including a wide variety of linear, cyclic, and polyfunctional types. Results show a trend of decreasing concentration with increasing carbon number, with the most abundant being glycine (41 n Moles/g). These and other results to be reviewed provide persuasive support for the theory of chemical evolution and provide the only natural evidence for the protobiological subset of molecules from which life on earth may have arisen.

  20. Examining compound-specific nitrogen isotopic composition of amino acids (δ15NAA) as a new proxy for sedimentary organic N

    NASA Astrophysics Data System (ADS)

    Batista, F.; Ravelo, A. C.; Mccarthy, M. D.

    2014-12-01

    The stable nitrogen (N) isotopic (δ15N) signature of marine sedimentary N (δ15Nbulk) is commonly applied as a proxy for the δ15N of sinking particulate organic matter (δ15NPOMsink), and by extension the δ15N of marine primary production. Although a general correspondence between the δ15Nbulk and δ15NPOMsink exists in shallow water, diagenesis or mixtures of N sources can affect this relationship. For instance, diagenesis δ15Nbulk enrichment as a function of water depth (Robinson et al., 2012), and terrestrial N sources can constitute a large portion of total sedimentary N near continental margins (Schubert & Calvert, 2001). Compound-specific amino acid analysis (δ15NAA) represents a new approach to address these issues. Proteins and peptides comprise the majority of N-containing molecules in living organisms; hence δ15NAA may be a direct proxy for organic N-δ15N (δ15NON). However, the relationship between δ15NAA data and major sedimentary N fractions has not been evaluated. We analyzed δ15NAA and the δ15N composition of major operationally defined N fractions and their relative contribution to total N from marine POM and shallow sediments collected in Santa Barbara Basin (SBB). Fractions analyzed include bulk, acid-soluble (AS), acid-insoluble (AI), and total hydrolysable amino acid (THAA). Average sedimentary δ15NTHAA and δ15NAS are enriched relative to δ15Nbulk by 2.9‰ and 1.0‰, respectively and δ15NAI is depleted relative to δ15Nbulk by ~1.5‰. The δ15NAS and δ15NTHAA are closest to subsurface nitrate δ15N (~8‰) in SBB, consistent with a primary N source, while depleted δ15NAI values are consistent with a dominant terrestrial N source. Together, these findings help to characterize the mixture of ON compounds, including hydrolysable AA, found in fresh biomass and suggest that δ15NTHAA represents a valuable new molecular level proxy for sedimentary proteinaceous material, but requires calibration to reconstruct δ15N of source N.

  1. Catalytic Destruction Of Toxic Organic Compounds

    NASA Technical Reports Server (NTRS)

    Voecks, Gerald E.

    1990-01-01

    Proposed process disposes of toxic organic compounds in contaminated soil or carbon beds safely and efficiently. Oxidizes toxic materials without producing such other contaminants as nitrogen oxides. Using air, fuel, catalysts, and steam, system consumes less fuel and energy than decontamination processes currently in use. Similar process regenerates carbon beds used in water-treatment plants.

  2. Assessment of the ozone-nitrogen oxide-volatile organic compound sensitivity of Mexico City through an indicator-based approach: measurements and numerical simulations comparison.

    PubMed

    Torres-Jardón, Ricardo; García-Reynoso, J Agustín; Jazcilevich, Arón; Ruiz-Suárez, L Gerardo; Keener, Tim C

    2009-10-01

    The ozone (O3) sensitivity to nitrogen oxides (NOx, or nitric oxide [NO] + nitrogen dioxide [NO2]) versus volatile organic compounds (VOCs) in the Mexico City metropolitan area (MCMA) is a current issue of scientific controversy. To shed light on this issue, we compared measurements of the indicator species O3/NOy (where NOy represents the sum of NO + NO2 + nitric acid [HNO3] + peroxyacetyl nitrate [PAN] + others), NOy, and the semiempirically derived O3/NOz(surrogate) (where NOz(surrogate) is the derived surrogate NOz, and NOz represents NOx reaction products, or NOy - NOx) with results of numerical predictions reproducing the transition regimes between NOx and VOC sensitivities. Ambient air concentrations of O3, NOx, and NOy were measured from April 14 to 25, 2004 in one downwind receptor site of photochemically aged air masses within Mexico City. MCMA-derived transition values for an episode day occurring during the same monitoring period were obtained through a series of photochemical simulations using the Multiscale Climate and Chemistry Model (MCCM). The comparison between the measured indicator species and the simulated spatial distribution of the indicators O3/ NOy, O3/NOz(surrogate), and NOy in MCMA suggest that O3 in this megacity is likely VOC-sensitive. This is in opposition to past studies that, on the basis of the observed morning VOC/NOx ratios, have concluded that O3 in Mexico City is NOx-sensitive. Simulated MCMA-derived sensitive transition values for O3/NOy, hydrogen peroxide (H2O2)/HNO3, and NOy were found to be in agreement with threshold criteria proposed for other regions in North America and Europe, although the transition crossover for O3/NOz and O3/HNO3 was not consistent with values reported elsewhere. An additional empirical evaluation of weekend/weekday differences in average maximum O3 concentrations and 6:00- to 9:00-a.m. NOx and NO levels registered at the same site in April 2004 indirectly confirmed the above results. A preliminary

  3. Integrated operation of the photorespiratory cycle and cytosolic metabolism in the modulation of primary nitrogen assimilation and export of organic N-transport compounds from leaves: a hypothesis.

    PubMed

    Misra, Jitendra B

    2014-02-15

    Photorespiration is generally considered to be an essentially dissipative process, although it performs some protective and essential functions. A theoretical appraisal indicates that the loss of freshly assimilated CO2 due to photorespiration in well-watered plants may not be as high as generally believed. Even under moderately adverse conditions, these losses may not exceed 10%. The photorespiratory metabolism of the source leaves of well-watered and well-nourished crop plants ought to be different from that of other leaves because the fluxes of the export of both carbohydrates and organic N-transport compounds in source leaves is quite high. With a heuristic approach that involved the dovetailing of certain metabolic steps with the photorespiratory cycle (PR-cycle), a novel network is proposed to operate in the source-leaves of well-watered and well-nourished plants. This network allows for the diversion of metabolites from their cyclic-routes in sizeable quantities. With the removal of considerable quantities of glycine and serine from the cyclic route, the number of RuBP oxygenation events would be several times those of the formation of hydroxypyruvate. Thus, to an extreme extent, photorespiratory metabolism would become open-ended and involve much less futile recycling of glycine and serine. Conversion of glyoxylate to glycine has been proposed to be a crucial step in the determination of the relative rates of the futile (cyclic) and anabolic (open-ended) routes. Thus, in the source leaves of well-watered and well-nourished plants, the importance of the cyclic route is limited to the salvaging of photorespiratory intermediates for the regeneration of RuBP. The proposed network is resilient enough to coordinate the rates of the assimilation of carbon and nitrogen in accordance with the moisture and N-fertility statuses of the soil.

  4. Volatile organic compounds (VOC), formaldehyde and nitrogen dioxide (NO2) in schools in Johor Bahru, Malaysia: Associations with rhinitis, ocular, throat and dermal symptoms, headache and fatigue.

    PubMed

    Norbäck, Dan; Hashim, Jamal Hisham; Hashim, Zailina; Ali, Faridah

    2017-03-15

    This paper studied associations between volatile organic compounds (VOC), formaldehyde, nitrogen dioxide (NO2) and carbon dioxide (CO2) in schools in Malaysia and rhinitis, ocular, nasal and dermal symptoms, headache and fatigue among students. Pupils from eight randomly selected junior high schools in Johor Bahru, Malaysia (N=462), participated (96%). VOC, formaldehyde and NO2 were measured by diffusion sampling (one week) and VOC also by pumped air sampling during class. Associations were calculated by multi-level logistic regression adjusting for personal factors, the home environment and microbial compounds in the school dust. The prevalence of weekly rhinitis, ocular, throat and dermal symptoms were 18.8%, 11.6%, 15.6%, and 11.1%, respectively. Totally 20.6% had weekly headache and 22.1% fatigue. Indoor CO2 were low (range 380-690 ppm). Indoor median NO2 and formaldehyde concentrations over one week were 23μg/m(3) and 2.0μg/m(3), respectively. Median indoor concentration of toluene, ethylbenzene, xylene, and limonene over one week were 12.3, 1.6, 78.4 and 3.4μg/m(3), respectively. For benzaldehyde, the mean indoor concentration was 2.0μg/m(3) (median<1μg/m(3)). Median indoor levels during class of benzene and cyclohexane were 4.6 and 3.7μg/m(3), respectively. NO2 was associated with ocular symptoms (p<0.001) and fatigue (p=0.01). Formaldehyde was associated with ocular (p=0.004), throat symptoms (p=0.006) and fatigue (p=0.001). Xylene was associated with fatigue (p<0.001) and benzaldehyde was associated with headache (p=0.03). In conclusion, xylene, benzaldehyde, formaldehyde and NO2 in schools can be risk factors for ocular and throat symptoms and fatigue among students in Malaysia. The indoor and outdoor levels of benzene were often higher than the EU standard of 5μg/m(3).

  5. Toxicity of six heterocyclic nitrogen compounds to Daphnia pulex

    SciTech Connect

    Perry, C.M.; Smith, S.B.

    1988-10-01

    The authors determined the relative toxicities to the aquatic crustacean Daphnia pulex of the six heterocyclic nitrogen compounds: 3-(1-methyl-2-pyrrolidinyl)pyridine (nicotine), 2-pyrrolidinone, 1-methylpyrrolidine, 2-(2-hydroxyethyl)pyridine, 2-amino-4,6-dimethylpyridine, and 2-amino-4,7(1H,8H)-pteridinedione(isoxanthopterin). These compounds were selected because they were detected in lake trout or walleyes and were commercially available. Daphnia pulex was used as the test organism because it is endemic to the Great Lakes, is easy to culture, has parthenogenic reproduction, constant genetic makeup over generations, and is sensitive to ecological stress.

  6. Participant-based monitoring of indoor and outdoor nitrogen dioxide, volatile organic compounds, and polycyclic aromatic hydrocarbons among MICA-Air households

    NASA Astrophysics Data System (ADS)

    Johnson, Markey M.; Williams, Ron; Fan, Zhihua; Lin, Lin; Hudgens, Edward; Gallagher, Jane; Vette, Alan; Neas, Lucas; Özkaynak, Halûk

    2010-12-01

    The Mechanistic Indicators of Childhood Asthma (MICA) study in Detroit, Michigan introduced a participant-based approach to reduce the resource burden associated with collection of indoor and outdoor residential air sampling data. A subset of participants designated as MICA-Air conducted indoor and outdoor residential sampling of nitrogen dioxide (NO 2), volatile organic compounds (VOCs), and polycyclic aromatic hydrocarbons (PAHs). This participant-based methodology was subsequently adapted for use in the Vanguard phase of the U.S. National Children's Study. The current paper examines residential indoor and outdoor concentrations of these pollutant species among health study participants in Detroit, Michigan. Pollutants measured under MICA-Air agreed well with other studies and continuous monitoring data collected in Detroit. For example, NO 2 and BTEX concentrations reported for other Detroit area monitoring were generally within 10-15% of indoor and outdoor concentrations measured in MICA-Air households. Outdoor NO 2 concentrations were typically higher than indoor NO 2 concentration among MICA-Air homes, with a median indoor/outdoor (I/O) ratio of 0.6 in homes that were not impacted by environmental tobacco smoke (ETS) during air sampling. Indoor concentrations generally exceeded outdoor concentrations for VOC and PAH species measured among non-ETS homes in the study. I/O ratios for BTEX species (benzene, toluene, ethylbenzene, and m/p- and o-xylene) ranged from 1.2 for benzene to 3.1 for toluene. Outdoor NO 2 concentrations were approximately 4.5 ppb higher on weekdays versus weekends. As expected, I/O ratios pollutants were generally higher for homes impacted by ETS. These findings suggest that participant-based air sampling can provide a cost-effective alternative to technician-based approaches for assessing indoor and outdoor residential air pollution in community health studies. We also introduced a technique for estimating daily concentrations at each

  7. Virtual Nitrogen Losses from Organic Food Production

    NASA Astrophysics Data System (ADS)

    Cattell Noll, L.; Galloway, J. N.; Leach, A. M.; Seufert, V.; Atwell, B.; Shade, J.

    2015-12-01

    Reactive nitrogen (Nr) is necessary for crop and animal production, but when it is lost to the environment, it creates a cascade of detrimental environmental impacts. The nitrogen challenge is to maximize the food production benefits of Nr, while minimizing losses to the environment. The first nitrogen footprint tool was created in 2012 to help consumers learn about the Nr losses to the environment that result from an individual's lifestyle choices. The nitrogen lost during food production was estimated with virtual nitrogen factors (VNFs) that quantify the amount of nitrogen lost to the environment per unit nitrogen consumed. Alternative agricultural systems, such as USDA certified organic farms, utilize practices that diverge from conventional production. In order to evaluate the potential sustainability of these alternative agricultural systems, our team calculated VNFs that reflect organic production. Initial data indicate that VNFs for organic grains and organic starchy roots are comparable to, but slightly higher than conventional (+10% and +20% respectively). In contrast, the VNF for organic vegetables is significantly higher (+90%) and the VNF for organic legumes is significantly lower (-90%). Initial data on organic meat production shows that organic poultry and organic pigmeat are comparable to conventional production (both <5% difference), but that the organic beef VNF is significantly higher (+30%). These data show that in some cases organic and conventional production are comparable in terms of nitrogen efficiency. However, since conventional production relies heavily on the creation of new reactive nitrogen (Haber-Bosch, biological nitrogen fixation) and organic production primarily utilizes already existing reactive nitrogen (manure, crop residue, compost), the data also show that organic production contributes less new reactive nitrogen to the environment than conventional production (approximately 70% less). Therefore, we conclude that on a local

  8. Organic Compounds in Carbonaceous Meteorites

    NASA Technical Reports Server (NTRS)

    Cooper, Grorge

    2001-01-01

    Carbonaceous meteorites are relatively enriched in soluble organic compounds. To date, these compounds provide the only record available to study a range of organic chemical processes in the early Solar System chemistry. The Murchison meteorite is the best-characterized carbonaceous meteorite with respect to organic chemistry. The study of its organic compounds has related principally to aqueous meteorite parent body chemistry and compounds of potential importance for the origin of life. Among the classes of organic compounds found in Murchison are amino acids, amides, carboxylic acids, hydroxy acids, sulfonic acids, phosphonic acids, purines and pyrimidines (Table 1). Compounds such as these were quite likely delivered to the early Earth in asteroids and comets. Until now, polyhydroxylated compounds (polyols), including sugars (polyhydroxy aldehydes or ketones), sugar alcohols, sugar acids, etc., had not been identified in Murchison. Ribose and deoxyribose, five-carbon sugars, are central to the role of contemporary nucleic acids, DNA and RNA. Glycerol, a three-carbon sugar alcohol, is a constituent of all known biological membranes. Due to the relative lability of sugars, some researchers have questioned the lifetime of sugars under the presumed conditions on the early Earth and postulated other (more stable) compounds as constituents of the first replicating molecules. The identification of potential sources and/or formation mechanisms of pre-biotic polyols would add to the understanding of what organic compounds were available, and for what length of time, on the ancient Earth.

  9. PERSISTENT PERFLUORINATED ORGANIC COMPOUNDS

    EPA Science Inventory

    Perfluorinated compounds (PFCs) have gained notoriety in the recent past. Global distribution of PFCs in wildlife, environmental samples and humans has sparked a recent increase in new investigations concerning PFCs. Historically PFCs have been used in a wide variety of consume...

  10. Organic Compounds in Stardust

    NASA Technical Reports Server (NTRS)

    McKay, David S.; Clemett. Simon J.; Sandford, Scott A.; Nakamura-Messenger, Keiko; Hoerz, Fredrich

    2011-01-01

    The successful return of the STARDUST spacecraft provides a unique opportunity to investigate the nature and distribution of organic matter in cometary dust particles collected from Comet 81P/Wild-2. Analysis of individual cometary impact tracks in silica aerogel using the technique of two-step laser mass spectrometry (L2MS) demonstrates the presence of complex aromatic organic matter. While concerns remain as to the organic purity of the aerogel collection medium and the thermal effects associated with hypervelocity capture, the majority of the observed organic species appear indigenous to the impacting particles and are hence of cometary origin. While the aromatic fraction of the total organic matter present is believed to be small, it is notable in that it appears to be N-rich. Spectral analysis in combination with instrumental detection sensitivities suggest that N is incorporated predominantly in the form of aromatic nitriles (R-C N). While organic species in the STARDUST samples do share some similarities with those present in the matrices of carbonaceous chondrites, the closest match is found with stratospherically collected interplanetary dust particles. These findings are consistent with the notion that a fraction of interplanetary dust is of cometary origin. The presence of complex organic N-containing species in comets has astrobiological implications since comets are likely to have contributed to the prebiotic chemical inventory of both the Earth and Mars.

  11. Biodegradability of nitrogenous compounds under anaerobic conditions and its estimation.

    PubMed

    Hongwei, Yang; Zhanpeng, Jiang; Shaoqi, Shi

    2006-02-01

    The anaerobic biodegradability of 23 nitrogenous compounds, including nitrogenous heterocyclic compounds and aliphatic amines, was tested and assessed in integration. These nitrogenous compounds were classified into readily, partially, and poorly biodegradable compounds after calculation of their integrated assessment indices (IAIs), Rules for anaerobic biodegradation of these compounds were also drawn. Stepwise regression and backpropagation artificial neural network (BP-ANN) methods were applied to establish quantitative structure-biodegradability relationships (QSBRs) based on the assessment results. In QSBR models, three molecular structure descriptors-second-order molecular connectivity index (2chi(V3)chi(v)p), and energy of the highest occupied molecular orbital (EHOMO)--were included. After analysis of the sensitivity of variables in QSBR models, it was found that the key molecular structure descriptor affecting anaerobic biodegradability of nitrogenous compounds is EHOMO, which is directly proportional to the anaerobic biodegradability of nitrogenous compounds.

  12. Formation of nitrogenated organic aerosols in the Titan upper atmosphere

    PubMed Central

    Imanaka, Hiroshi; Smith, Mark A.

    2010-01-01

    Many aspects of the nitrogen fixation process by photochemistry in the Titan atmosphere are not fully understood. The recent Cassini mission revealed organic aerosol formation in the upper atmosphere of Titan. It is not clear, however, how much and by what mechanism nitrogen is incorporated in Titan’s organic aerosols. Using tunable synchrotron radiation at the Advanced Light Source, we demonstrate the first evidence of nitrogenated organic aerosol production by extreme ultraviolet–vacuum ultraviolet irradiation of a N2/CH4 gas mixture. The ultrahigh-mass-resolution study with laser desorption ionization-Fourier transform-ion cyclotron resonance mass spectrometry of N2/CH4 photolytic solid products at 60 and 82.5 nm indicates the predominance of highly nitrogenated compounds. The distinct nitrogen incorporations at the elemental abundances of H2C2N and HCN, respectively, are suggestive of important roles of H2C2N/HCCN and HCN/CN in their formation. The efficient formation of unsaturated hydrocarbons is observed in the gas phase without abundant nitrogenated neutrals at 60 nm, and this is confirmed by separately using 13C and 15N isotopically labeled initial gas mixtures. These observations strongly suggest a heterogeneous incorporation mechanism via short lived nitrogenated reactive species, such as HCCN radical, for nitrogenated organic aerosol formation, and imply that substantial amounts of nitrogen is fixed as organic macromolecular aerosols in Titan’s atmosphere. PMID:20616074

  13. Determination of the concentration of nitrogenous bio-organic compounds using an isotope ratio mass spectrometer operating in continuous flow mode.

    PubMed

    Tea, Illa; Kosieradzka, Katarzyna; Antheaume, Ingrid; Gentil, Emmanuel; Robins, Richard J

    2011-09-01

    The quality of the determination of compound-specific isotopic content at natural abundance by gas chromatography-isotope ratio measurement-mass spectrometry (GC-irm-MS) relies on the stability of the voltage generated by the ion detector Faraday cages. The application of GC-irm-MS to the determination of δ(13)C (‰) and δ(15)N (‰) is now routine. However, for numerous applications, it is necessary to determine both the isotope content (δ(15)N) and the quantity (in micromoles) of analyte present. We now show that it is possible for nitrogen-containing compounds to measure how much analyte is present with an irm mass spectrometer linked to a GC by exploiting the integrated N(2) total ion current intensity (Vs) generated by measuring the (15)N/(14)N isotope ratio. The method is validated over a range of concentration (2-70 mmol/L) and δ(15)N (-70 to +50‰) values for six molecules of diverse chemical nature and functionality (nortropine, norpseudotropine, nortropinone, cysteine, taurine, glutathione). It is shown that once the ion current is calibrated, the quantitative values are of a comparable quality to those obtained from GC with flame ionization detection (GC-FID). In addition, it is demonstrated that over a definable range, the δ(15)N (‰) value is independent of the quantity of analyte introduced, confirming the validity of this method.

  14. Photochemical dimerization of organic compounds

    DOEpatents

    Crabtree, Robert H.; Brown, Stephen H.; Muedas, Cesar A.; Ferguson, Richard R.

    1992-01-01

    At least one of selectivity and reaction rate of photosensitized vapor phase dimerizations, including dehydrodimerizations, hydrodimerizations and cross-dimerizations of saturated and unsaturated organic compounds is improved by conducting the dimerization in the presence of hydrogen or nitrous oxide.

  15. Transformation of nitrogen compounds in the tundra soils of Northern Fennoscandia

    NASA Astrophysics Data System (ADS)

    Maslov, M. N.; Makarov, M. I.

    2016-07-01

    The transformation of organic nitrogen compounds in the soils of tundra ecosystems of Northern Fennoscandia has been studied under laboratory and natural conditions. Tundra soils contain significant reserves of total nitrogen, but they are poor in its extractable mineral and organic forms. The potential rates of the net mineralization and net immobilization of nitrogen by microorganisms vary among the soils and depend on the C: N ratio in the extractable organic matter and microbial biomass of soil. Under natural conditions, the rate of nitrogen net mineralization is lower than the potential rate determined under laboratory conditions by 6-25 times. The incubation of tundra soils in the presence of plants does not result in the accumulation of mineral nitrogen compounds either in the soil or in microbial biomass. This confirms the high competitive capacity of plants under conditions of limited nitrogen availability in tundra ecosystems.

  16. Biomedical Compounds from Marine organisms

    PubMed Central

    Jha, Rajeev Kumar; Zi-rong, Xu

    2004-01-01

    The Ocean, which is called the ‘mother of origin of life’, is also the source of structurally unique natural products that are mainly accumulated in living organisms. Several of these compounds show pharmacological activities and are helpful for the invention and discovery of bioactive compounds, primarily for deadly diseases like cancer, acquired immuno-deficiency syndrome (AIDS), arthritis, etc., while other compounds have been developed as analgesics or to treat inflammation, etc. The life-saving drugs are mainly found abundantly in microorganisms, algae and invertebrates, while they are scarce in vertebrates. Modern technologies have opened vast areas of research for the extraction of biomedical compounds from oceans and seas.

  17. Photoprotective compounds from marine organisms.

    PubMed

    Rastogi, Rajesh P; Richa; Sinha, Rajeshwar P; Singh, Shailendra P; Häder, Donat-P

    2010-06-01

    The substantial loss in the stratospheric ozone layer and consequent increase in solar ultraviolet radiation on the earth's surface have augmented the interest in searching for natural photoprotective compounds in organisms of marine as well as freshwater ecosystems. A number of photoprotective compounds such as mycosporine-like amino acids (MAAs), scytonemin, carotenoids and several other UV-absorbing substances of unknown chemical structure have been identified from different organisms. MAAs form the most common class of UV-absorbing compounds known to occur widely in various marine organisms; however, several compounds having UV-screening properties still need to be identified. The synthesis of scytonemin, a predominant UV-A-photoprotective pigment, is exclusively reported in cyanobacteria. Carotenoids are important components of the photosynthetic apparatus that serve both light-harvesting and photoprotective functions, either by direct quenching of the singlet oxygen or other toxic reactive oxygen species or by dissipating the excess energy in the photosynthetic apparatus. The production of photoprotective compounds is affected by several environmental factors such as different wavelengths of UVR, desiccation, nutrients, salt concentration, light as well as dark period, and still there is controversy about the biosynthesis of various photoprotective compounds. Recent studies have focused on marine organisms as a source of natural bioactive molecules having a photoprotective role, their biosynthesis and commercial application. However, there is a need for extensive work to explore the photoprotective role of various UV-absorbing compounds from marine habitats so that a range of biotechnological and pharmaceutical applications can be found.

  18. Compound-specific amino acid δ15N patterns in marine algae: Tracer potential for cyanobacterial vs. eukaryotic organic nitrogen sources in the ocean

    NASA Astrophysics Data System (ADS)

    McCarthy, Matthew D.; Lehman, Jennifer; Kudela, Raphael

    2013-02-01

    Stable nitrogen isotopic analysis of individual amino acids (δ15N-AA) has unique potential to elucidate the complexities of food webs, track heterotrophic transformations, and understand diagenesis of organic nitrogen (ON). While δ15N-AA patterns of autotrophs have been shown to be generally similar, prior work has also suggested that differences may exist between cyanobacteria and eukaryotic algae. However, δ15N-AA patterns in differing oceanic algal groups have never been closely examined. The overarching goals of this study were first to establish a more quantitative understanding of algal δ15N-AA patterns, and second to examine whether δ15N-AA patterns have potential as a new tracer for distinguishing prokaryotic vs. eukaryotic N sources. We measured δ15N-AA from prokaryotic and eukaryotic phytoplankton cultures and used a complementary set of statistical approaches (simple normalization, regression-derived fractionation factors, and multivariate analyses) to test for variations. A generally similar δ15N-AA pattern was confirmed for all algae, however significant AA-specific variation was also consistently identified between the two groups. The relative δ15N fractionation of Glx (glutamine + glutamic acid combined) vs. total proteinaceous N appeared substantially different, which we hypothesize could be related to differing enzymatic forms. In addition, the several other AA (most notably glycine and leucine) appeared to have strong biomarker potential. Finally, we observed that overall patterns of δ15N values in algae correspond well with the Trophic vs. Source-AA division now commonly used to describe variable AA δ15N changes with trophic transfer, suggesting a common mechanistic basis. Overall, these results show that autotrophic δ15N-AA patterns can differ between major algal evolutionary groupings for many AA. The statistically significant multivariate results represent a first approach for testing ideas about relative eukaryotic vs. prokaryotic

  19. Characteristics and transformations of dissolved organic nitrogen in municipal biological nitrogen removal wastewater treatment plants

    NASA Astrophysics Data System (ADS)

    Huo, Shouliang; Xi, Beidou; Yu, Honglei; Qin, Yanwen; Zan, Fengyu; Zhang, Jingtian

    2013-12-01

    Dissolved organic nitrogen (DON) represents most of the dissolved nitrogen in the effluent of biological nitrogen removal (BNR) wastewater treatment plants (WWTPs). The characteristics of wastewater-derived DON in two different WWTPs were investigated by several different methods. The major removals of DON and biodegradable dissolved organic nitrogen (BDON) along the treatment train were observed in the anaerobic process. Dissolved combined amino acids (DCAA) and dissolved free amino acids (DFAA) in the effluent accounted approximately for less than 4% and 1% of the effluent DON, respectively. Approximately half of wastewater-derived DON was capable of passing through a 1 kDa ultrafilter, and low MW DON cannot effectively be removed by BNR processes. More than 80% of effluent DON was composed of hydrophilic compounds, which stimulate algal growth. The study provided important information for future upgrading of WWTPs or the selection of DON removal systems to meet more demanding nitrogen discharge limits.

  20. Removal of basic nitrogen compounds from hydrocarbon liquids

    DOEpatents

    Givens, Edwin N.; Hoover, David S.

    1985-01-01

    A method is provided for reducing the concentration of basic nitrogen compounds in hydrocarbonaceous feedstock fluids used in the refining industry by providing a solid particulate carbonaceous adsorbent/fuel material such as coal having active basic nitrogen complexing sites on the surface thereof and the coal with a hydrocarbonaceous feedstock containing basic nitrogen compounds to facilitate attraction of the basic nitrogen compounds to the complexing sites and the formation of complexes thereof on the surface of the coal. The adsorbent coal material and the complexes formed thereon are from the feedstock fluid to provide a hydrocarbonaceous fluid of reduced basic nitrogen compound concentration. The coal can then be used as fuel for boilers and the like.

  1. Students' Categorizations of Organic Compounds

    ERIC Educational Resources Information Center

    Domin, Daniel S.; Al-Masum, Mohammad; Mensah, John

    2008-01-01

    Categorization is a fundamental psychological ability necessary for problem solving and many other higher-level cognitive tasks. In organic chemistry, students must establish groupings of different chemical compounds in order not only to solve problems, but also to understand course content. Classic models of categorization emphasize similarity as…

  2. Investigation of nitrogenous compound formation in biomass gasification

    SciTech Connect

    Ishimura, D.M.; Masutani, S.M.; Kinoshita, C.M.

    1994-12-31

    Gasification of high nitrogen content biomass can produce large quantities of nitrogenous compounds that pose potential risks to the environment and human health, and can compromise the performance of related energy conversion processes. Few studies of nitrogenous compound formation in gasification have been reported and little is known about the evolution of fuel-bound nitrogen from biomass fuels. To address these deficiencies, Leucaena, a nitrogen-fixing tree and possible energy crop with 2-3% nitrogen content, was gasified in a bench-scale, indirectly-heated, fluidized bed gasifier to determine the effects of operating conditions on nitrogeneous compound formation. Gas chromatography, and ion-selective electrode and chemiluminescence analyzers were used to measure concentrations of major gas species (e.g., CO, CO{sub 2}, H{sub 2}, CH{sub 4}, and N{sub 2}), NH{sub 3}, HCN, NO{sub x}, and nitrogeneous tar species as functions of gasifier temperature (700{degrees}C to 900{degrees}C), equivalence ration (0.2 to 0.4), and residence time (2.3 to 6.7 s). Nitrogeneous compounds were inventoried, and fundamental conclusions, based on the findings of these tests, are proposed.

  3. Chloroflexi CL500-11 Populations That Predominate Deep-Lake Hypolimnion Bacterioplankton Rely on Nitrogen-Rich Dissolved Organic Matter Metabolism and C1 Compound Oxidation

    PubMed Central

    Mueller, Ryan S.; Chiang, Edna; Liebig, James R.; Vanderploeg, Henry A.

    2015-01-01

    The Chloroflexi CL500-11 clade contributes a large proportion of the bacterial biomass in the oxygenated hypolimnia of deep lakes worldwide, including the world's largest freshwater system, the Laurentian Great Lakes. Traits that allow CL500-11 to thrive and its biogeochemical role in these environments are currently unknown. Here, we found that a CL500-11 population was present mostly in offshore waters along a transect in ultraoligotrophic Lake Michigan (a Laurentian Great Lake). It occurred throughout the water column in spring and only in the hypolimnion during summer stratification, contributing up to 18.1% of all cells. Genome reconstruction from metagenomic data suggested an aerobic, motile, heterotrophic lifestyle, with additional energy being gained through carboxidovory and methylovory. Comparisons to other available streamlined freshwater genomes revealed that the CL500-11 genome contained a disproportionate number of cell wall/capsule biosynthesis genes and the most diverse spectrum of genes involved in the uptake of dissolved organic matter (DOM) substrates, particularly peptides. In situ expression patterns indicated the importance of DOM uptake and protein/peptide turnover, as well as type I and type II carbon monoxide dehydrogenase and flagellar motility. Its location in the water column influenced its gene expression patterns the most. We observed increased bacteriorhodopsin gene expression and a response to oxidative stress in surface waters compared to its response in deep waters. While CL500-11 carries multiple adaptations to an oligotrophic lifestyle, its investment in motility, its large cell size, and its distribution in both oligotrophic and mesotrophic lakes indicate its ability to thrive under conditions where resources are more plentiful. Our data indicate that CL500-11 plays an important role in nitrogen-rich DOM mineralization in the extensive deep-lake hypolimnion habitat. PMID:26682860

  4. Metabolism of nitrogenous compounds by ruminant liver.

    PubMed

    Reynolds, C K

    1992-03-01

    Ruminants absorb substantial amounts of ammonia nitrogen and very little glucose. Ammonia absorbed is removed by the liver and converted to urea, which can be recycled to the digestive tract and add to the pool of ammonia absorbed. When ammonia absorption and liver urea production are increased by changes in nitrogen intake, an associated increase in liver alpha-amino nitrogen removal has been observed. Reasons for the increase in liver removal of amino acids with greater ureagenesis are uncertain, but the aspartate/glutamate requirement of ureagenesis and the complex relationships between ureagenesis and the tricarboxylic acid cycle, glucogenesis, liver energy metabolism and redox state all may be involved. Amino acids represent potential sources of carbon for liver glucogenesis and precise reckonings of the contributions of amino acid carbon to glucogenesis are needed for ruminants fed differing diets. There is evidence for the involvement of peptides in liver nitrogen exchanges and amino acids in peptides represent a potential source of carbon for glucogenesis and nitrogen for ureagenesis. A number of endocrine factors have an impact on liver nitrogen metabolism in ruminants. Growth hormone decreases liver urea release and increases liver glutamate release.

  5. SPECTROSCOPIC STUDY OF SORPTION OF NITROGEN HETEROCYCLIC COMPOUNDS ON PHYLLOSILICATES

    EPA Science Inventory

    The present study focused on understanding the sorption characteristics of acridine (AcN)and acridine-9-carboxylic acid (AcNCOOH), two typical nitrogen heterocyclic compounds (NHCs), on well-characterized phyllosilicates (hectorite, saponite, and muscovite). Results presented in...

  6. Potential of the compound specific isotope analysis of individual amino acid for studying past nitrogen cycle

    NASA Astrophysics Data System (ADS)

    Choi, Bohyung; Shin, Kyung-Hoon

    2016-04-01

    The nitrogen isotope ratio of bulk sediment has been widely used for studying nitrogen cycle in the marine environment. However, since organic nitrogen in sediment is regarded as a mixture of organic matter, it is challenging to identify its exact sources. Recently, compound specific nitrogen isotope analysis of amino acid (CSIA AAs) has been introduced as a potential tool for complement of bulk nitrogen isotope since amino acid more directly reflects information on primary producer and trophic position. However, studies on CSIA of amino acid in sediments are scarce due to the complexities of the analytical method and relatively high analytica costl. In this study, we established a method of the CSIA AAs which is more suitable for the analysis of sediments and accessed if the CSIA AAs can be used for the study of past nitrogen cycle.

  7. Cementation reactions in the presence of nitrogen compounds.

    PubMed

    El Batouti, Mervette

    2003-07-15

    The effect of aniline derivatives on the rate of cementation of copper from dilute copper sulfate solution on iron rods was investigated. The variables studied were concentration of CuSO(4), temperature, organic additives, and their concentrations. It was found that the cementation reaction was first-order in the presence and in the absence of additives. Nitrogen compounds were found to decrease the rate of cementation by 10 to 80% depending on the type of inhibitor as well as its concentration.The adsorption isotherm, the effect of temperature, and the percentage inhibition show that the order of inhibition is p-chloroaniline>o-chloroaniline>m-chloroaniline and p-chloroaniline>p-aminobenzoic acid>p-aminoacetophenone. The thermodynamic parameters DeltaS( not equal ), DeltaG( not equal ), DeltaH( not equal ) were given.

  8. Organic nitrogen in PM2.5 aerosol at a forest site in the Southeast US

    EPA Science Inventory

    There is growing evidence that organo-nitrogen compounds may constitute a significant fraction of the aerosol nitrogen (N) budget. In this study, the concentration of organic nitrogen (ON) and major inorganic ions in PM2.5 aerosol were measured at the Duke Forest Research Facilit...

  9. Preparation of high nitrogen compound and materials therefrom

    DOEpatents

    Huynh, My Hang V.; Hiskey, Michael A.

    2006-10-10

    The high-nitrogen compound of the formula ##STR00001## was prepared. Pyrolysis of the compound yields carbon nitrides C.sub.2N.sub.3 and C.sub.3N.sub.5. The carbon nitrides vary in their density, texture, and morphology.

  10. Volatile organic compound sensor system

    DOEpatents

    Schabron, John F.; Rovani, Jr., Joseph F.; Bomstad, Theresa M.; Sorini-Wong, Susan S.; Wong, Gregory K.

    2011-03-01

    Generally, this invention relates to the development of field monitoring methodology for new substances and sensing chemical warfare agents (CWAs) and terrorist substances. It also relates to a portable test kit which may be utilized to measure concentrations of halogenated volatile organic compounds (VOCs) in the field. Specifically it relates to systems for reliably field sensing the potential presence of such items while also distinguishing them from other elements potentially present. It also relates to overall systems and processes for sensing, reacting, and responding to an indicated presence of such substance, including modifications of existing halogenated sensors and arrayed sensing systems and methods.

  11. Volatile organic compound sensor system

    DOEpatents

    Schabron, John F.; Rovani, Jr., Joseph F.; Bomstad, Theresa M.; Sorini-Wong, Susan S.

    2009-02-10

    Generally, this invention relates to the development of field monitoring methodology for new substances and sensing chemical warfare agents (CWAs) and terrorist substances. It also relates to a portable test kit which may be utilized to measure concentrations of halogenated volatile organic compounds (VOCs) in the field. Specifically it relates to systems for reliably field sensing the potential presence of such items while also distinguishing them from other elements potentially present. It also relates to overall systems and processes for sensing, reacting, and responding to an indicated presence of such substance, including modifications of existing halogenated sensors and arrayed sensing systems and methods.

  12. The effect of high pressure on nitrogen compounds of milk

    NASA Astrophysics Data System (ADS)

    Kielczewska, Katarzyna; Czerniewicz, Maria; Michalak, Joanna; Brandt, Waldemar

    2004-04-01

    The effect of pressurization at different pressures (from 200 to 1000 MPa, at 200 MPa intervals, tconst. = 15 min) and periods of time (from 15 to 35 min, at 10 min intervals, pconst. = 800 MPa) on the changes of proteins and nitrogen compounds of skimmed milk was studied. The pressurization caused an increase in the amount of soluble casein and denaturation of whey proteins. The level of nonprotein nitrogen compounds and proteoso-peptone nitrogen compounds increased as a result of the high-pressure treatment. These changes increased with an increase in pressure and exposure time. High-pressure treatment considerably affected the changes in the conformation of milk proteins, which was reflected in the changes in the content of proteins sedimenting and an increase in their degree of hydration.

  13. Nitrogen-sulfur compounds in stratospheric aerosols

    NASA Technical Reports Server (NTRS)

    Farlow, N. H.; Snetsinger, K. G.; Hayes, D. M.; Lem, H. Y.; Tooper, B. M.

    1978-01-01

    Two forms of nitrosyl sulfuric acid (NOHSO4 and NOHS2O7) have been tentatively identified in stratospheric aerosols. The first of these can be formed either directly from gas reactions of NO2 with SO2 or by gas-particle interactions between NO2 and H2SO4. The second product may form when SO3 is involved. Estimates based on these reactions suggest that the maximum quantity of NO that might be absorbed in stratospheric aerosols could vary from one-third to twice the amount of NO in the surrounding air. If these reactions occur in the stratosphere, then a mechanism exists for removing nitrogen oxides from that region by aerosol particle fallout. This process may typify another natural means that helps cleanse the lower stratosphere of excessive pollutants.

  14. 77 FR 46961 - Approval and Promulgation of Implementation Plans; Wisconsin; Volatile Organic Compound Emission...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-08-07

    ... AGENCY 40 CFR Part 52 Approval and Promulgation of Implementation Plans; Wisconsin; Volatile Organic... Volatile Organic Compound (VOC) emissions in moderate ozone nonattainment areas. Wisconsin's VOC rules..., Intergovernmental relations, Nitrogen dioxide, Ozone, Reporting and recordkeeping requirements, Volatile...

  15. Electrochemical wastewater treatment: influence of the type of carbon and of nitrogen on the organic load removal.

    PubMed

    Fernandes, Annabel; Coelho, João; Ciríaco, Lurdes; Pacheco, Maria José; Lopes, Ana

    2016-12-01

    Boron-doped diamond (BDD) and Ti/Pt/PbO2 anodes were utilized to perform the electrodegradation of synthetic samples containing humic acid in the presence of different organic and inorganic carbon-containing and nitrogen-containing compounds. The influence of the chloride ion in the degradation process of the different synthetic samples was also assessed. The results showed that the anodic oxidation process can efficiently degrade recalcitrant compounds such as humic acid. The presence of carbonate in solution enhances the nitrogen removal, whereas it hinders the oxidation of the organic compounds. When organic nitrogen is present, it is converted to NH4(+), which in turn is oxidized to nitrate and to volatile nitrogen compounds. Hydroxyl radicals are more prone to oxidize the organic nitrogen than the ammonium nitrogen. The presence of chloride enhances the organic matter and nitrogen removal rates, BDD being the anode material that yields the highest removals.

  16. Precursors and factors affecting formation of haloacetonitriles and chloropicrin during chlor(am)ination of nitrogenous organic compounds in drinking water.

    PubMed

    Jia, Aiyin; Wu, Chunde; Duan, Yan

    2016-05-05

    This study investigated the precursors and factors affecting formation of haloacetonitriles (HANs) and chloropicrin (TCNM) during chlorination/chloramination of eight amino acids in the effluent water of V-type clarifying filtration from a drinking water treatment plant. The yields of trichloroacetonitrile (TCAN), dichloroacetonitrile (DCAN) and TCNM were higher during chlorination than during chloramination. Tyrosine and tryptophan produced the greatest amount of DCAN and also generated a small amount of TCAN during chlorination process. Besides, the yields of DCAN were higher than TCNM during chlorination/chloramination. Contact time, Cl2:org-N molar ratios, pH, temperature and bromide ion affected nitrogenous disinfection by-products (N-DBPs) formation during chlorination of tryptophan in different degrees. TCAN, DCAN and TCNM formation showed the increasing and then decreasing with prolonged contact time. Higher Cl2:org-N molar ratios improved N-DBPs formation within a certain range. The pH affected N-DBPs formation differently. HANs increased with increasing pH from 5 to 6 and decreased with increasing pH from 6 to 9, while TCNM increased with increasing pH from 5 to 9. Higher temperatures enhanced TCNM formation, but reduced the formation of TCAN and DCAN. The presence of bromide ions improved the yields of HANs and TCNM and shifted N-DBPs to more brominated ones.

  17. Volatile organic compound sensing devices

    DOEpatents

    Lancaster, Gregory D.; Moore, Glenn A.; Stone, Mark L.; Reagen, William K.

    1995-01-01

    Apparatus employing vapochromic materials in the form of inorganic double complex salts which change color reversibly when exposed to volatile organic compound (VOC) vapors is adapted for VOC vapor detection, VOC aqueous matrix detection, and selective VOC vapor detection. The basic VOC vapochromic sensor is incorporated in various devices such as a ground probe sensor, a wristband sensor, a periodic sampling monitor, a soil/water penetrometer, an evaporative purge sensor, and various vacuum-based sensors which are particularly adapted for reversible/reusable detection, remote detection, continuous monitoring, or rapid screening of environmental remediation and waste management sites. The vapochromic sensor is used in combination with various fiber optic arrangements to provide a calibrated qualitative and/or quantitative indication of the presence of VOCs.

  18. Volatile organic compound sensing devices

    DOEpatents

    Lancaster, G.D.; Moore, G.A.; Stone, M.L.; Reagen, W.K.

    1995-08-29

    Apparatus employing vapochromic materials in the form of inorganic double complex salts which change color reversibly when exposed to volatile organic compound (VOC) vapors is adapted for VOC vapor detection, VOC aqueous matrix detection, and selective VOC vapor detection. The basic VOC vapochromic sensor is incorporated in various devices such as a ground probe sensor, a wristband sensor, a periodic sampling monitor, a soil/water penetrometer, an evaporative purge sensor, and various vacuum-based sensors which are particularly adapted for reversible/reusable detection, remote detection, continuous monitoring, or rapid screening of environmental remediation and waste management sites. The vapochromic sensor is used in combination with various fiber optic arrangements to provide a calibrated qualitative and/or quantitative indication of the presence of VOCs. 15 figs.

  19. Improvements to the Characterization of Organic Nitrogen Chemistry

    EPA Science Inventory

    Excess atmospheric nitrogen deposition can cause significant harmful effects to ecosystems. Organic nitrogen deposition can be an important contributor to the total nitrogen budget, contributing 10-30%, however there are large uncertainties in the chemistry and deposition of thes...

  20. Characterizations of organic compounds in diesel exhaust particulates.

    PubMed

    Lim, Jaehyun; Lim, Cheolsoo; Kim, Sangkyun; Hong, Jihyung

    2015-08-01

    To characterize how the speed and load of a medium-duty diesel engine affected the organic compounds in diesel particle matter (PM) below 1 μm, four driving conditions were examined. At all four driving conditions, concentration of identifiable organic compounds in PM ultrafine (34-94 nm) and accumulation (94-1000 nm) modes ranged from 2.9 to 5.7 μg/m(3) and 9.5 to 16.4 μg/m(3), respectively. As a function of driving conditions, the non-oxygen-containing organics exhibited a reversed concentration trend to the oxygen-containing organics. The identified organic compounds were classified into eleven classes: alkanes, alkenes, alkynes, aromatic hydrocarbons, carboxylic acids, esters, ketones, alcohols, ethers, nitrogen-containing compounds, and sulfur-containing compounds. At all driving conditions, alkane class consistently showed the highest concentration (8.3 to 18.0 μg/m(3)) followed by carboxylic acid, esters, ketones and alcohols. Twelve polycyclic aromatic hydrocarbons (PAHs) were identified with a total concentration ranging from 37.9 to 174.8 ng/m(3). In addition, nine nitrogen-containing polycyclic aromatic compounds (NPACs) were identified with a total concentration ranging from 7.0 to 10.3 ng/m(3). The most abundant PAH (phenanthrene) and NPACs (7,8-benzoquinoline and 3-nitrophenanthrene) comprise a similar molecular (3 aromatic-ring) structure under the highest engine speed and engine load.

  1. Toxicity of six heterocyclic nitrogen compounds to Daphnia pulex

    USGS Publications Warehouse

    Perry, Cynthia M.; Smith, Stephen B.

    1988-01-01

    We determined the relative toxicities to the aquatic crustacean Daphniz pulex of six heterocyclic nitrogen compunds. These compounds were selected because they were detected in lake trout or walleyes and were commercially available. Stress to the daphnid populations may affect forage fish populations that depend either directly or indirectly on zooplankton as a food source in the Great Lakes.

  2. Atmospheric nitrogen compounds II: emissions, transport, transformation, deposition and assessment

    NASA Astrophysics Data System (ADS)

    Aneja, Viney P.; Roelle, Paul A.; Murray, George C.; Southerland, James; Erisman, Jan Willem; Fowler, David; Asman, Willem A. H.; Patni, Naveen

    The Atmospheric Nitrogen Compounds II: Emissions, Transport, Transformation, Deposition and Assessment workshop was held in Chapel Hill, NC from 7 to 9 June 1999. This international conference, which served as a follow-up to the workshop held in March 1997, was sponsored by: North Carolina Department of Environment and Natural Resources; North Carolina Department of Health and Human Services, North Carolina Office of the State Health Director; Mid-Atlantic Regional Air Management Association; North Carolina Water Resources Research Institute; Air and Waste Management Association, RTP Chapter; the US Environmental Protection Agency and the North Carolina State University (College of Physical and Mathematical Sciences, and North Carolina Agricultural Research Service). The workshop was structured as an open forum at which scientists, policy makers, industry representatives and others could freely share current knowledge and ideas, and included international perspectives. The workshop commenced with international perspectives from the United States, Canada, United Kingdom, the Netherlands, and Denmark. This article summarizes the findings of the workshop and articulates future research needs and ways to address nitrogen/ammonia from intensively managed animal agriculture. The need for developing sustainable solutions for managing the animal waste problem is vital for shaping the future of North Carolina. As part of that process, all aspects of environmental issues (air, water, soil) must be addressed as part of a comprehensive and long-term strategy. There is an urgent need for North Carolina policy makers to create a new, independent organization that will build consensus and mobilize resources to find technologically and economically feasible solutions to this aspect of the animal waste problem.

  3. Compound-specific nitrogen isotopes of equatorial Pacific sedimentary record

    NASA Astrophysics Data System (ADS)

    Sauthoff, W.; Ravelo, A. C.; Mccarthy, M. D.

    2014-12-01

    Compound specific nitrogen isotopic analysis of amino acids (δ15N-AA) is a technique that is widely used in regional ecology and food web studies, with newly expanding applications in organic geochemistry. However, its applicability to marine sediment has been minimally examined. This study is one of the first δ15N-AA applications into the paleorecord of marine sediment. We explore how δ15N-AA measurements provide insights into past changes in water column N cycling and N utilization, and into post-depositional processes that impact sedimentary N. This is possible because δ15N-AA investigates the molecular-level basis of the bulk sedimentary δ15N signal, revealing possible diagenetic alteration of sedimentary organic matter. Our goal was is to investigate the extent of alteration (vs. preservation) of individual sedimentary amino acid δ15N values from surface nitrate δ15N across a wide range of depositional environments. The δ15N of bulk sediment differs from that of the surface nitrate δ15N signal because of water column processes or more often because of alteration of the signal during initial sedimentation. To investigate this alteration we compare δ15N-AA to bulk δ15N measurements in a suite of equatorial Pacific core tops (378-4360 m below sea level) across contrasting oceanographic and sedimentary depositional conditions (e.g. high vs. low productivity, hypoxic vs. oxic bottom waters). To examine down core diagenetic alteration of the sediment record, we present δ15N-AA and bulk δ15N of selected deeper depths to observe 1) if diagenetic shift is coherently resolved by both types of measurements and 2) if select individual δ15N-AA values remain representative of the surface organic δ15N signal. We hypothesize that compound specific analysis (δ15N-AA) will provide a molecular level assessment of mechanism for diagenetic changes in bulk organic δ15N values while also preserving detailed information about planktonic ecosystem structure.

  4. [Effect of carcinogenic nitrogen-containing compounds on cell metabolism].

    PubMed

    Antropov, V I; Samoĭlov, V O; Slepian, É I

    2012-01-01

    The brown frog (Rana temporaria) skin cells respiration, calcium metabolism and glycolysis, the tree frog (Hyla arborea) skin cells respiration and calcium metabolism were studied under short-term (first hours) and long-term (first days) exposure to nitrogenous compounds [N-nitroso-N-methyl urea (NMU) and thiourea (TU)]. The first direct effect of nitrogenous compounds exposure was cell breathing inhibition occurring in Rana temporaria skin cells after 28 days of exposure, and in Hyla arborea skin cells after 8 days of exposure. These changes were precided by decrease of lactate dehydrogenase (LDH) activity in Rana temporaria skin cells starting 16 days after NMU and TU introduction. The increase of intracellular calcium level was noted in tree frog skin cells 4-8 days after NMU and TU introduction, in brown frogs skin cells this parameter was unchanged.

  5. A new material for selective removal of nitrogen compounds from gasoils towards more efficient HDS processes.

    PubMed

    Macaud, Mathieu; Schulz, Emmanuelle; Vrinat, Michel; Lemaire, Marc

    2002-10-21

    A selective removal of nitrogen compounds from gasoils is proposed, using a recyclable sorbent capable of forming charge-transfer complexes; the selective elimination of nitrogen compounds strongly improves the hydrodesulfurization (HDS) of denitrogenated feed.

  6. Study of nitrogen containing compounds in the polar troposphere.

    PubMed

    Ianniello, Antonietta; Sparapani, Roberto; Allegrini, Ivo; Vazzana, Caterina; Mazziotti, Carla; De Teran, Gomez; Montagnoli, Mauro; Fino, Alessandra; Felici, Andrea

    2003-01-01

    Atmospheric nitrogen compounds play a critical role in tropospheric photochemistry and are crucial to understand the chemical and physical evolution of atmospheric pollutants in polar areas. Measurements of these species in remote areas are rare, although their relevance is well established. Sampling campaigns of gaseous and particulate atmospheric trace species were performed in Arctic and in Antarctica during three consecutive years (1997-1999), using a proper combination of annular denuders and filter pack. After sampling, the ionic species were extracted with aqueous solutions and analysed by means of ion chromatography. Quality assurance on the sampling and analytical steps allowed accurate and precise measurements of all relevant compounds, which are thought to be important to nitrogen chemistry, at very low concentration levels. In addition, the measurements also included a multistage low-pressure impactor for the collection of particulate matter in different size regions (0.035-15.9 mm). Results obtained from these campaigns demonstrate that the minor components may be measured at levels as low as a few nanograms per cubic meter. The reported concentrations are to be considered among the first observations of nitrogen containing compounds in polar sites.

  7. Special applications of fluorinated organic compounds.

    PubMed

    Lewandowski, Grzegorz; Meissner, Egbert; Milchert, Eugeniusz

    2006-08-25

    The applications of fluorinated organic compounds (FOCs) as finishing agent for fabrics, components of extinguishing agents, electroplating bathes, lubricating oils, oxygen carriers in blood substitutes have been discussed. Recent achievements in methods of the fluorination and general principles of the synthesis of useful perfluorinated organic compounds are given as well.

  8. METHOD FOR THE PREPARATION OF BINARY NITROGEN-FLUORINE COMPOUNDS

    DOEpatents

    Frazer, J.W.

    1962-05-01

    A process is given for preparing binary nitrogenfluorine compounds, in particular, tetrafluorohydrazine (N/sub 2/F/sub 4/) and difluorodiazine (N/sub 2/ F/sub 2/), The process comprises subjecting gaseous nitrogen trifluoride to the action of an alternating current electrical glow discharge in the presence of mercury vapors. By the action of the electrical discharge, the nitrogen trifluoride is converted into a gaseous product comprising a mixture of tetrafluorohydrazine, the isomers of difluorodiazine, and other impurities including nitrogen, nitrogen oxides, silicon tetrafiuoride, and unreacted nitrogen trifluoride. The gaseous products and impurities are passed into a trap maintained at about - 196 deg C to freeze out the desired products and impurities with the exception of nitregen gas which passes off from the trap and is discarded. Subsequently, the desired products and remaining impurities are warmed to the gaseous state and passed through a silica gel trap maintained at about - 55DEC, wherein the desired tetrafluorohydrazine and difluorodiazine products are retained while the remaining gaseous impurities pass therethrough. The desired products are volatilized from the silica gel trap by heating and then separated by gas chrounatography means into the respective tetrafluorohydrazine and difluorodiazine products. (A.e.C)

  9. High-resolution mass spectrometry of nitrogenous compounds of the Colorado Green River formation oil shale.

    NASA Technical Reports Server (NTRS)

    Simoneit, B. R.; Schnoes, H. K.; Haug, P.; Burlingame, A. L.

    1971-01-01

    Basic nitrogenous compounds isolated from extracts of Green River Formation oil shale were analyzed. The major homologous constituents found were the compositional types - namely, quinolines, tetrahydrequinolines with minor amounts of pyridines and indoles series and traces of more aromatized nitrogen compounds. These results are correlated with nitrogen compounds isolated from Green River Formation retort oil and are a survey of the unaltered nitrogen compounds indigeneous to the shale.

  10. Characterization of organic nitrogen in IBCSP coals. Final technical report, September 1, 1990--August 31, 1991

    SciTech Connect

    Kruge, M.A.

    1991-12-31

    The overall objective of this study was to determine the content and distribution of organic nitrogen in a series of IBCSP coals and their isolated macerals. The specific objectives were: to determine the bulk nitrogen contents for coals, isolated macerals, oxidation products and residues, solvent extracts and their liquid chromatographic fractions, and pyrolyzates; to determine the distribution of organic nitrogen in all coal derivatives enumerated in Objective 1 which are Gas Chromatography (GC)-amenable. This will be accomplished by GC-Thermionic Specific Detectors; to determine the molecular structure of the major nitrogen compounds detected in Objective 2, using mass spectrometry.

  11. Molecular characterization of nitrogen and sulfur containing compounds in night-time SOA

    NASA Astrophysics Data System (ADS)

    Iinuma, Yoshiteru; Mutzel, Anke; Rodigast, Maria; Böge, Olaf; Herrmann, Hartmut

    2014-05-01

    The oxidation of volatile organic compounds (VOCs) leads to the formation of low volatile organic compounds that can form secondary organic aerosol (SOA). Studies in the past showed that laboratory generated and ambient SOA are made of polar molecules with O/C ratios generally greater than 0.5. More recent studies have shown that SOA compounds can contain heteroatoms mainly sulfur and nitrogen atoms. Offline chemical analysis with high-resolution mass spectrometers and fragmentation experiments has shown that sulphur containing compounds are mainly organosulfates and nitrogen containing species are aromatic heterocyclic compounds such as imidazole and nitrated aromatic compounds such as nitrophenols. In addition to these, SOA compounds containing both sulfur and nitrogen have been reported from the analysis of ambient organic aerosol, rainwater, fog and cloud samples. Based on the mass spectrometric evidence these compounds are attributed to nitrooxy-organosulfates originating from isoprene and monoterpenes. Although these compounds are ubiquitously detected in the ambient samples, reports about their detection in laboratory generated SOA are scares and their formation mechanisms are not well understood. In the present study, we investigated the formation of sulfur and nitrogen containing SOA species in the oxidation of biogenic VOCs. Photooxidation and night-time oxidation experiments were performed in a smog chamber to produce SOA samples. The laboratory generated SOA samples were analysed with UPLC-IMS-TOFMS (Ultra Performance Liquid Chromatography coupled to Ion Mobility Spectrometry and Time of Flight Mass Spectrometry). The presence of highly acidic sulphate seed particles (pH0) did not promote the formation of compounds with chemical formula of C10H17NO7S- and m/z value of 294.0653, indicating that the formation mechanisms of these compounds unlikely involve the ring opening reactions of epoxides and subsequent sulfation reactions. On the other hand, their

  12. Biodegradation of halogenated organic compounds.

    PubMed Central

    Chaudhry, G R; Chapalamadugu, S

    1991-01-01

    In this review we discuss the degradation of chlorinated hydrocarbons by microorganisms, emphasizing the physiological, biochemical, and genetic basis of the biodegradation of aliphatic, aromatic, and polycyclic compounds. Many environmentally important xenobiotics are halogenated, especially chlorinated. These compounds are manufactured and used as pesticides, plasticizers, paint and printing-ink components, adhesives, flame retardants, hydraulic and heat transfer fluids, refrigerants, solvents, additives for cutting oils, and textile auxiliaries. The hazardous chemicals enter the environment through production, commercial application, and waste. As a result of bioaccumulation in the food chain and groundwater contamination, they pose public health problems because many of them are toxic, mutagenic, or carcinogenic. Although synthetic chemicals are usually recalcitrant to biodegradation, microorganisms have evolved an extensive range of enzymes, pathways, and control mechanisms that are responsible for catabolism of a wide variety of such compounds. Thus, such biological degradation can be exploited to alleviate environmental pollution problems. The pathways by which a given compound is degraded are determined by the physical, chemical, and microbiological aspects of a particular environment. By understanding the genetic basis of catabolism of xenobiotics, it is possible to improve the efficacy of naturally occurring microorganisms or construct new microorganisms capable of degrading pollutants in soil and aquatic environments more efficiently. Recently a number of genes whose enzyme products have a broader substrate specificity for the degradation of aromatic compounds have been cloned and attempts have been made to construct gene cassettes or synthetic operons comprising these degradative genes. Such gene cassettes or operons can be transferred into suitable microbial hosts for extending and custom designing the pathways for rapid degradation of recalcitrant

  13. Worldwide organic soil carbon and nitrogen data

    SciTech Connect

    Zinke, P.J.; Stangenberger, A.G.; Post, W.M.; Emanual, W.R.; Olson, J.S.

    1986-09-01

    The objective of the research presented in this package was to identify data that could be used to estimate the size of the soil organic carbon pool under relatively undisturbed soil conditions. A subset of the data can be used to estimate amounts of soil carbon storage at equilibrium with natural soil-forming factors. The magnitude of soil properties so defined is a resulting nonequilibrium values for carbon storage. Variation in these values is due to differences in local and geographic soil-forming factors. Therefore, information is included on location, soil nitrogen content, climate, and vegetation along with carbon density and variation.

  14. Methods of making organic compounds by metathesis

    DOEpatents

    Abraham, Timothy W.; Kaido, Hiroki; Lee, Choon Woo; Pederson, Richard L.; Schrodi, Yann; Tupy, Michael John

    2015-09-01

    Described are methods of making organic compounds by metathesis chemistry. The methods of the invention are particularly useful for making industrially-important organic compounds beginning with starting compositions derived from renewable feedstocks, such as natural oils. The methods make use of a cross-metathesis step with an olefin compound to produce functionalized alkene intermediates having a pre-determined double bond position. Once isolated, the functionalized alkene intermediate can be self-metathesized or cross-metathesized (e.g., with a second functionalized alkene) to produce the desired organic compound or a precursor thereto. The method may be used to make bifunctional organic compounds, such as diacids, diesters, dicarboxylate salts, acid/esters, acid/amines, acid/alcohols, acid/aldehydes, acid/ketones, acid/halides, acid/nitriles, ester/amines, ester/alcohols, ester/aldehydes, ester/ketones, ester/halides, ester/nitriles, and the like.

  15. Method of manufacturing semiconductor having group II-group VI compounds doped with nitrogen

    DOEpatents

    Compaan, Alvin D.; Price, Kent J.; Ma, Xianda; Makhratchev, Konstantin

    2005-02-08

    A method of making a semiconductor comprises depositing a group II-group VI compound onto a substrate in the presence of nitrogen using sputtering to produce a nitrogen-doped semiconductor. This method can be used for making a photovoltaic cell using sputtering to apply a back contact layer of group II-group VI compound to a substrate in the presence of nitrogen, the back coating layer being doped with nitrogen. A semiconductor comprising a group II-group VI compound doped with nitrogen, and a photovoltaic cell comprising a substrate on which is deposited a layer of a group II-group VI compound doped with nitrogen, are also included.

  16. The role of nitrogen reduction in the photocatalytic degradation of nitroaromatic compounds

    SciTech Connect

    Schmelling, D.C.; Gray, K.A.

    1995-12-31

    One interesting characteristic of the photocatalytic behavior of organic compounds containing nitrogen heteroatoms is their tendency to produce both oxidized arid reduced transformation products in an aerated reactor. This presentation will describe the results of research utilizing model nitroaromatic compounds such as nitrobenzene and nitrophenols to develop mechanistic and kinetic information concerning interfacial reduction of nitroaromatic compounds in aqueous photocatalytic systems. TiO{sub 2} thin film electrodes are employed in open-circuit photovoltage and closed-circuit photocurrent analyses to give kinetic data describing the ability of nitrobenzene and its predominant organic by-products to serve as electron acceptors in varying solution conditions. Consideration of the photocatalytic transformation products which are formed when the photocatalyst electrode is subjected to anodic bias provides additional information about the role of conduction band electrons in compound degradation.

  17. Microbial Turnover of Fixed Nitrogen Compounds in Oceanic Crustal Fluids

    NASA Astrophysics Data System (ADS)

    Kraft, B.; Wankel, S. D.; Glazer, B. T.; Huber, J. A.; Girguis, P. R.

    2014-12-01

    Oceanic crust is the largest aquifer on Earth, with a massive volume of seawater advecting through the basaltic crust. The microbiome of this deep marine subsurface biosphere has been estimated to be substantial, and consequently their metabolic activity may have major influences on global biogeochemical cycles. While earlier and recent studies provide insight into the microbial community composition of oceanic crustal fluids, information on the microbial ecophysiology is broadly missing. Therefore, to investigate the microbial transformation of fixed nitrogen compounds in crustal aquifer fluids, fluids were sampled from different horizons of two neighbouring CORK (Circulation Obviation Retrofit Kit) observatories at the North Pond sediment pond. This site is located on the western flank of the Mid Atlantic Ridge and is characterized by relatively young oceanic crust and cold fluids. The crustal fluids contain oxygen and nitrate, which potentially both may serve as electron acceptor for respiration. In a multidisciplinary approach we combined stable isotope incubations, determination of the natural isotopic compositions and plan to analyse relevant functional genes from a metagenomic dataset to investigate the nitrogen cycling at North Pond. The turnover of fixed nitrogen in oceanic crustal fluids may have important implications for the understanding of the global nitrogen cycle.

  18. Alkylation of organic aromatic compounds

    DOEpatents

    Smith, L.A. Jr.

    1989-07-18

    Aromatic compounds are alkylated in a catalytic distillation, wherein the catalyst structure also serves as a distillation component by contacting the aromatic compound with a C[sub 2] to C[sub 10] olefin in the catalyst bed under 0.25 to 50 atmospheres of pressure and at temperatures in the range of 80 C to 500 C, using as the catalyst a mole sieve characterized as acidic or an acidic cation exchange resin. For example, ethyl benzene is produced by feeding ethylene below the catalyst bed while benzene is conveniently added through the reflux in molar excess to that required to react with ethylene, thereby reacting substantially all of the ethylene and recovering benzene as the principal overhead and ethyl benzene in the bottoms. 1 fig.

  19. Alkylation of organic aromatic compounds

    DOEpatents

    Smith, Jr., Lawrence A.; Arganbright, Robert P.; Hearn, Dennis

    1994-01-01

    Aromatic compounds are alkylated in a catalytic distillation, wherein the catalyst structure also serves as a distillation component by contacting the aromatic compound with a C.sub.2 to C.sub.10 olefin in the catalyst bed under 0.25 to 50 atmospheres of pressure and at temperatures in the range of 80.degree. C. to 500.degree. C., using as the catalyst a mole sieve characterized as acidic or an acidic cation exchange resin. For example, ethyl benzene is produced by feeding ethylene below the catalyst bed while benzene is conveniently added through the reflux in molar excess to that required to react with ethylene, thereby reacting substantially all of the ethylene and recovering benzene as the principal overhead and ethyl benzene in the bottoms.

  20. Alkylation of organic aromatic compounds

    DOEpatents

    Smith, L.A. Jr.; Arganbright, R.P.; Hearn, D.

    1993-09-07

    Aromatic compounds are alkylated in a catalytic distillation, wherein the catalyst structure also serves as a distillation component by contacting the aromatic compound with a C[sub 2] to C[sub 10] olefin in the catalyst bed under 0.25 to 50 atmospheres of pressure and at temperatures in the range of 80 C to 500 C, using as the catalyst a molecular sieve characterized as acidic or an acidic cation exchange resin. For example, ethyl benzene is produced by feeding ethylene to about the mid point of the catalyst bed while benzene is conveniently added through the reflux in molar excess to that required to react with ethylene, thereby reacting substantially all of the ethylene and recovering benzene as the principal overhead and ethyl benzene in the bottoms. 1 figures.

  1. Alkylation of organic aromatic compounds

    DOEpatents

    Smith, Jr., Lawrence A.

    1989-01-01

    Aromatic compounds are alkylated in a catalytic distillation, wherein the catalyst structure also serves as a distillation component by contacting the aromatic compound with a C.sub.2 to C.sub.10 olefin in the catalyst bed under 0.25 to 50 atmospheres of pressure and at temperatures in the range of 80.degree. C. to 500.degree. C., using as the catalyst a mole sieve characterized as acidic or an acidic cation exchange resin. For example, ethyl benzene is produced by feeding ethylene below the catalyst bed while benzene is conveniently added through the reflux in molar excess to that required to react with ethylene, thereby reacting substantially all of the ethylene and recovering benzene as the principal overhead and ethyl benzene in the bottoms.

  2. Alkylation of organic aromatic compounds

    DOEpatents

    Smith, Jr., Lawrence A.; Arganbright, Robert P.; Hearn, Dennis

    1993-01-01

    Aromatic compounds are alkylated in a catalytic distillation, wherein the catalyst structure also serves as a distillation component by contacting the aromatic compound with a C.sub.2 to C.sub.10 olefin in the catalyst bed under 0.25 to 50 atmospheres of pressure and at temperatures in the range of 80.degree. C. to 500.degree. C., using as the catalyst a mole sieve characterized as acidic or an acidic cation exchange resin. For example, ethyl benzene is produced by feeding ethylene to about the mid point of the catalyst bed while benzene is conveniently added through the reflux in molar excess to that required to react with ethylene, thereby reacting substantially all of the ethylene and recovering benzene as the principal overhead and ethyl benzene in the bottoms.

  3. Alkylation of organic aromatic compounds

    DOEpatents

    Smith, L.A. Jr.; Arganbright, R.P.; Hearn, D.

    1994-06-14

    Aromatic compounds are alkylated in a catalytic distillation, wherein the catalyst structure also serves as a distillation component by contacting the aromatic compound with a C[sub 2] to C[sub 10] olefin in the catalyst bed under 0.25 to 50 atmospheres of pressure and at temperatures in the range of 80 C to 500 C, using as the catalyst a molecular sieve characterized as acidic or an acidic cation exchange resin. For example, ethyl benzene is produced by feeding ethylene below the catalyst bed while benzene is conveniently added through the reflux in molar excess to that required to react with ethylene, thereby reacting substantially all of the ethylene and recovering benzene as the principal overhead and ethyl benzene in the bottoms. 1 fig.

  4. IDENTIFICATION AND QUANTIFICATION OF AEROSOL POLAR OXYGENATED COMPOUNDS BEARING CARBOXYLIC OR HYDROXYL GROUPS. 2. ORGANIC TRACER COMPOUNDS FROM MONOTERPENES

    EPA Science Inventory

    A comparison was made of polar organic compounds found in the field with those produced in secondary organic aerosol from laboratory irradiations of natural hydrocarbons and oxides of nitrogen. The field samples comprised atmospheric particulate matter (PM2.5) collect...

  5. Organic nitrogen storage in mineral soil: Implications for policy and management.

    PubMed

    Bingham, Andrew H; Cotrufo, M Francesca

    2016-05-01

    Nitrogen is one of the most important ecosystem nutrients and often its availability limits net primary production as well as stabilization of soil organic matter. The long-term storage of nitrogen-containing organic matter in soils was classically attributed to chemical complexity of plant and microbial residues that retarded microbial degradation. Recent advances have revised this framework, with the understanding that persistent soil organic matter consists largely of chemically labile, microbially processed organic compounds. Chemical bonding to minerals and physical protection in aggregates are more important to long-term (i.e., centuries to millennia) preservation of these organic compounds that contain the bulk of soil nitrogen rather than molecular complexity, with the exception of nitrogen in pyrogenic organic matter. This review examines for the first time the factors and mechanisms at each stage of movement into long-term storage that influence the sequestration of organic nitrogen in the mineral soil of natural temperate ecosystems. Because the factors which govern persistence are different under this newly accepted paradigm we examine the policy and management implications that are altered, such as critical load considerations, nitrogen saturation and mitigation consequences. Finally, it emphasizes how essential it is for this important but underappreciated pool to be better quantified and incorporated into policy and management decisions, especially given the lack of evidence for many soils having a finite capacity to sequester nitrogen.

  6. Thermodynamic properties of organic iodine compounds

    NASA Astrophysics Data System (ADS)

    Richard, Laurent; Gaona, Xavier

    2011-11-01

    A critical evaluation has been made of the thermodynamic properties reported in the literature for 43 organic iodine compounds in the solid, liquid, or ideal gas state. These compounds include aliphatic, cyclic and aromatic iodides, iodophenols, iodocarboxylic acids, and acetyl and benzoyl iodides. The evaluation has been made on the basis of carbon number systematics and group additivity relations, which also allowed to provide estimates of the thermodynamic properties of those compounds for which no experimental data were available. Standard molal thermodynamic properties at 25 °C and 1 bar and heat capacity coefficients are reported for 13 crystalline, 29 liquid, and 39 ideal gas organic iodine compounds, which can be used to calculate the corresponding properties as a function of temperature and pressure. Values derived for the standard molal Gibbs energy of formation at 25 °C and 1 bar of these crystalline, liquid, and ideal gas organic iodine compounds have subsequently been combined with either solubility measurements or gas/water partition coefficients to obtain values for the standard partial molal Gibbs energies of formation at 25 °C and 1 bar of 32 aqueous organic iodine compounds. The thermodynamic properties of organic iodine compounds calculated in the present study can be used together with those for aqueous inorganic iodine species to predict the organic/inorganic speciation of iodine in marine sediments and petroleum systems, or in the near- and far-field of nuclear waste repositories.

  7. Organic electronic devices using phthalimide compounds

    DOEpatents

    Hassan, Azad M.; Thompson, Mark E.

    2012-10-23

    Organic electronic devices comprising a phthalimide compound. The phthalimide compounds disclosed herein are electron transporters with large HOMO-LUMO gaps, high triplet energies, large reduction potentials, and/or thermal and chemical stability. As such, these phthalimide compounds are suitable for use in any of various organic electronic devices, such as OLEDs and solar cells. In an OLED, the phthalimide compounds may serve various functions, such as a host in the emissive layer, as a hole blocking material, or as an electron transport material. In a solar cell, the phthalimide compounds may serve various functions, such as an exciton blocking material. Various examples of phthalimide compounds which may be suitable for use in the present invention are disclosed.

  8. Organic electronic devices using phthalimide compounds

    DOEpatents

    Hassan, Azad M.; Thompson, Mark E.

    2013-03-19

    Organic electronic devices comprising a phthalimide compound. The phthalimide compounds disclosed herein are electron transporters with large HOMO-LUMO gaps, high triplet energies, large reduction potentials, and/or thermal and chemical stability. As such, these phthalimide compounds are suitable for use in any of various organic electronic devices, such as OLEDs and solar cells. In an OLED, the phthalimide compounds may serve various functions, such as a host in the emissive layer, as a hole blocking material, or as an electron transport material. In a solar cell, the phthalimide compounds may serve various functions, such as an exciton blocking material. Various examples of phthalimide compounds which may be suitable for use in the present invention are disclosed.

  9. Organic electronic devices using phthalimide compounds

    DOEpatents

    Hassan, Azad M.; Thompson, Mark E.

    2010-09-07

    Organic electronic devices comprising a phthalimide compound. The phthalimide compounds disclosed herein are electron transporters with large HOMO-LUMO gaps, high triplet energies, large reduction potentials, and/or thermal and chemical stability. As such, these phthalimide compounds are suitable for use in any of various organic electronic devices, such as OLEDs and solar cells. In an OLED, the phthalimide compounds may serve various functions, such as a host in the emissive layer, as a hole blocking material, or as an electron transport material. In a solar cell, the phthalimide compounds may serve various functions, such as an exciton blocking material. Various examples of phthalimide compounds which may be suitable for use in the present invention are disclosed.

  10. Microwave spectra of some volatile organic compounds

    NASA Technical Reports Server (NTRS)

    White, W. F.

    1975-01-01

    A computer-controlled microwave (MRR) spectrometer was used to catalog reference spectra for chemical analysis. Tables of absorption frequency, peak absorption intensity, and integrated intensity are included for 26 volatile organic compounds, all but one of which contain oxygen.

  11. VOLATILE ORGANIC COMPOUNDS AS EXPOSURE BIOMARKERS

    EPA Science Inventory

    Alveolar breath sampling and analysis can be extremely useful in exposure assessment studies involving volatile organic compounds (VOCs). Over recent years scientists from the US Environmental Protection Agency's National Exposure Research Laboratory have developed and refined...

  12. PERFLUORINATED ORGANIC COMPOUND EXPOSURE ASSESSMENT RESEARCH

    EPA Science Inventory

    A wide range of perfluorinated organic compounds (PFCs) has been used in a variety of industrial processes and consumer products. The most commonly studied PFCs include perfluorooctane sulfonate (PFOS) and perfluorooctanoic acid (PFOA), but there are many more compounds in this c...

  13. (CHINA) PERFLUORINATED ORGANIC COMPOUND EXPOSURE ASSESSMENT RESEARCH

    EPA Science Inventory

    A wide range of perfluorinated organic compounds (PFCs) has been used in a variety of industrial processes and consumer products. The most commonly studied PFCs include perfluorooctane sulfonate (PFOS) and perfluorooctanoic acid (PFOA), but there are many more compounds in this c...

  14. Volatile organic compound emissions from silage systems

    Technology Transfer Automated Retrieval System (TEKTRAN)

    As a precursor to smog, emission of volatile organic compounds (VOCs) to the atmosphere is an environmental concern in some regions. The major source from farms is silage, with emissions coming from the silo face, mixing wagon, and feed bunk. The major compounds emitted are alcohols with other impor...

  15. VOLATILE ORGANIC COMPOUNDS (VOCS) CHAPTER 31.

    EPA Science Inventory

    The term "volatile organic compounds' (VOCs) was originally coined to refer, as a class, to carbon-containing chemicals that participate in photochemical reactions in the ambient (outdoor) are. The regulatory definition of VOCs used by the U.S. EPA is: Any compound of carbon, ex...

  16. Alkylation of organic aromatic compounds

    DOEpatents

    Smith, L.A. Jr.; Arganbright, R.P.; Hearn, D.

    1993-01-05

    Aromatic compounds are alkylated in a combination reactor/distillation column comprising a vessel suitable for operating between 70 C and 500 C and from 0.5 to 20 atmospheres pressure; an inert distillation packing in the lower one-third of said vessel; solid acidic catalytic material such as zeolites or an acidic cation exchange resin supported in the middle one-third of said vessel; and inert distillation packing in the upper one-third of said vessel. A benzene inlet is located near the upper end of the vessel; an olefin inlet is juxtaposed with said solid acidic catalytic material; a bottoms outlet is positioned near the bottom of said vessel for removing said cumene and ethyl benzene; and an overhead outlet is placed at the top of said vessel for removing any unreacted benzene and olefin.

  17. Alkylation of organic aromatic compounds

    DOEpatents

    Smith, Jr., Lawrence A.; Arganbright, Robert P.; Hearn, Dennis

    1993-01-01

    Aromatic compounds are alkylated in a combination reactor/distillation column comprising a vessel suitable for operating between 70.degree. C. and 500.degree. C. and from 0.5 to 20 atmospheres pressure; an inert distillation packing in the lower one-third of said vessel; solid acidic catalytic material such as zeolites or an acidic cation exchange resin supported in the middle one-third of said vessel; and inert distillation packing in the upper one-third of said vessel. A benzene inlet is located near the upper end of the vessel; an olefin inlet is juxtaposed with said solid acidic catalytic material; a bottoms outlet is positioned near the bottom of said vessel for removing said cumene and ethyl benzene; and an overhead outlet is placed at the top of said vessel for removing any unreacted benzene and olefin.

  18. MICROBIAL DEGRADATION OF NITROGEN, OXYGEN AND SULFUR HETEROCYCLIC COMPOUNDS UNDER ANAEROBIC CONDITIONS: STUDIES WITH AQUIFER SAMPLES

    EPA Science Inventory

    The potential for anaerobic biodegradation of 12 heterocyclic model compounds was studied. Nine of the model compounds were biotransformed in aquifer slurries under sulfate-reducing or methanogenic conditions. The nitrogen and oxygen heterocyclic compounds were more susceptible t...

  19. Formation of xenon-nitrogen compounds at high pressure

    PubMed Central

    Howie, Ross T.; Turnbull, Robin; Binns, Jack; Frost, Mungo; Dalladay-Simpson, Philip; Gregoryanz, Eugene

    2016-01-01

    Molecular nitrogen exhibits one of the strongest known interatomic bonds, while xenon possesses a closed-shell electronic structure: a direct consequence of which renders both chemically unreactive. Through a series of optical spectroscopy and x-ray diffraction experiments, we demonstrate the formation of a novel van der Waals compound formed from binary Xe-N2 mixtures at pressures as low as 5 GPa. At 300 K and 5 GPa Xe(N2)2-I is synthesised, and if further compressed, undergoes a transition to a tetragonal Xe(N2)2-II phase at 14 GPa; this phase appears to be unexpectedly stable at least up to 180 GPa even after heating to above 2000 K. Raman spectroscopy measurements indicate a distinct weakening of the intramolecular bond of the nitrogen molecule above 60 GPa, while transmission measurements in the visible and mid-infrared regime suggest the metallisation of the compound at ~100 GPa. PMID:27748357

  20. Atmospheric Chemistry of Micrometeoritic Organic Compounds

    NASA Technical Reports Server (NTRS)

    Kress, M. E.; Belle, C. L.; Pevyhouse, A. R.; Iraci, L. T.

    2011-01-01

    Micrometeorites approx.100 m in diameter deliver most of the Earth s annual accumulation of extraterrestrial material. These small particles are so strongly heated upon atmospheric entry that most of their volatile content is vaporized. Here we present preliminary results from two sets of experiments to investigate the fate of the organic fraction of micrometeorites. In the first set of experiments, 300 m particles of a CM carbonaceous chondrite were subject to flash pyrolysis, simulating atmospheric entry. In addition to CO and CO2, many organic compounds were released, including functionalized benzenes, hydrocarbons, and small polycyclic aromatic hydrocarbons. In the second set of experiments, we subjected two of these compounds to conditions that simulate the heterogeneous chemistry of Earth s upper atmosphere. We find evidence that meteor-derived compounds can follow reaction pathways leading to the formation of more complex organic compounds.

  1. Enhancing the biodegradation of oil in sandy sediments with choline: a naturally methylated nitrogen compound.

    PubMed

    Mortazavi, Behzad; Horel, Agota; Anders, Jennifer S; Mirjafari, Arsalan; Beazley, Melanie J; Sobecky, Patricia A

    2013-11-01

    We investigated how additions of choline, a naturally occurring methylated nitrogen-containing compound, accelerated hydrocarbon degradation in sandy sediments contaminated with moderately weathered crude oil (4000 mg kg(-1) sediment). Addition of lauroylcholine chloride (LCC) and tricholine citrate (TCC) to oil contaminated sediments resulted in 1.6 times higher hydrocarbon degradation rates compared to treatments without added choline derivatives. However, the degradation rate constant for the oil contaminated sediments amended with LCC was similar to that in contaminated sediments amended with inorganic nitrogen, phosphorus, and glucose. Additions of LLC and TCC to sediments containing extensively weathered oil also resulted in enhanced mineralization rates. Cultivation-free 16S rRNA analysis revealed the presence of an extant microbial community with clones closely related to known hydrocarbon degraders from the Gammaproteobacteria, Alphaproteobacteria, and Firmicutes phyla. The results demonstrate that the addition of minimal amounts of organic compounds to oil contaminated sediments enhances the degradation of hydrocarbons.

  2. Possible complex organic compounds on Mars.

    PubMed

    Kobayashi, K; Sato, T; Kajishima, S; Kaneko, T; Ishikawa, Y; Saito, T

    1997-01-01

    It is suggested that primitive Mars had somehow similar environments as primitive Earth. If life was born on the primitive earth using organic compounds which were produced from the early Earth environment, the same types of organic compounds were also formed on primitive Mars. Such organic compounds might have been preserved on Mars still now. We are studying possible organic formation on primitive and present Mars. A gaseous mixture of CO2, CO, N2 and H2O with various mixing ratios were irradiated with high energy protons (major components of cosmic rays). Hydrogen cyanide and formaldehyde were detected among volatile products, and yellow-brown-colored water-soluble non-volatile substances were produced, which gave amino acids after acid-hydrolysis. Major part of "amino acid precursors" were not simple molecules like aminonitriles, but complex compounds which eluted earlier than free amino acids in cation-exchange HPLC. These organic compounds should be major targets in the future Mars mission. Strategy for the detection of the complex organics on Mars will be discussed.

  3. Nitrogen

    USGS Publications Warehouse

    Apodaca, Lori E.

    2013-01-01

    The article presents an overview of the nitrogen chemical market as of July 2013, including the production of ammonia compounds. Industrial uses for ammonia include fertilizers, explosives, and plastics. Other topics include industrial capacity of U.S. ammonia producers CF Industries Holdings Inc., Koch Nitrogen Co., PCS Nitrogen, Inc., and Agrium Inc., the impact of natural gas prices on the nitrogen industry, and demand for corn crops for ethanol production.

  4. Photocatalytic oxidation of organic compounds on Mars

    NASA Technical Reports Server (NTRS)

    Chun, S. F. S.; Pang, K. D.; Cutts, J. A.; Ajello, J. M.

    1978-01-01

    Ultraviolet-stimulated catalytic oxidation is proposed as a mechanism for the destruction of organic compounds on Mars. The process involves the presence of gaseous oxygen, UV radiation, and a catalyst (titanium dioxide), and all three of these have been found to be present in the Martian environment. Therefore it seems plausible that UV-stimulated oxidation of organics is responsible for degrading organic molecules into inorganic end products.

  5. Reflectance spectroscopy of organic compounds: 1. Alkanes

    USGS Publications Warehouse

    Clark, R.N.; Curchin, J.M.; Hoefen, T.M.; Swayze, G.A.

    2009-01-01

    Reflectance spectra of the organic compounds comprising the alkane series are presented from the ultraviolet to midinfrared, 0.35 to 15.5 /??m. Alkanes are hydrocarbon molecules containing only single carbon-carbon bonds, and are found naturally on the Earth and in the atmospheres of the giant planets and Saturn's moon, Titan. This paper presents the spectral properties of the alkanes as the first in a series of papers to build a spectral database of organic compounds for use in remote sensing studies. Applications range from mapping the environment on the Earth, to the search for organic molecules and life in the solar system and throughout the. universe. We show that the spectral reflectance properties of organic compounds are rich, with major diagnostic spectral features throughout the spectral range studied. Little to no spectral change was observed as a function of temperature and only small shifts and changes in the width of absorption bands were observed between liquids and solids, making remote detection of spectral properties throughout the solar system simpler. Some high molecular weight organic compounds contain single-bonded carbon chains and have spectra similar to alkanes even ' when they fall into other families. Small spectral differences are often present allowing discrimination among some compounds, further illustrating the need to catalog spectral properties for accurate remote sensing identification with spectroscopy.

  6. 40 CFR 721.5330 - Nickel salt of an organo compound containing nitrogen.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Nickel salt of an organo compound... Specific Chemical Substances § 721.5330 Nickel salt of an organo compound containing nitrogen. (a) Chemical... as nickel salt of an organo compound containing nitrogen (PMN P-92-686) is subject to reporting...

  7. 40 CFR 721.5330 - Nickel salt of an organo compound containing nitrogen.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 32 2012-07-01 2012-07-01 false Nickel salt of an organo compound... Specific Chemical Substances § 721.5330 Nickel salt of an organo compound containing nitrogen. (a) Chemical... as nickel salt of an organo compound containing nitrogen (PMN P-92-686) is subject to reporting...

  8. 40 CFR 721.5330 - Nickel salt of an organo compound containing nitrogen.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Nickel salt of an organo compound... Specific Chemical Substances § 721.5330 Nickel salt of an organo compound containing nitrogen. (a) Chemical... as nickel salt of an organo compound containing nitrogen (PMN P-92-686) is subject to reporting...

  9. 40 CFR 721.5330 - Nickel salt of an organo compound containing nitrogen.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Nickel salt of an organo compound... Specific Chemical Substances § 721.5330 Nickel salt of an organo compound containing nitrogen. (a) Chemical... as nickel salt of an organo compound containing nitrogen (PMN P-92-686) is subject to reporting...

  10. 40 CFR 721.5330 - Nickel salt of an organo compound containing nitrogen.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Nickel salt of an organo compound... Specific Chemical Substances § 721.5330 Nickel salt of an organo compound containing nitrogen. (a) Chemical... as nickel salt of an organo compound containing nitrogen (PMN P-92-686) is subject to reporting...

  11. Governing processes for reactive nitrogen compounds in the atmosphere in relation to ecosystem, climatic and human health impacts

    NASA Astrophysics Data System (ADS)

    Hertel, O.; Skjøth, C. A.; Reis, S.; Bleeker, A.; Harrison, R.; Cape, J. N.; Fowler, D.; Skiba, U.; Simpson, D.; Jickells, T.; Kulmala, M.; Gyldenkærne, S.; Sørensen, L. L.; Erisman, J. W.; Sutton, M. A.

    2012-07-01

    Reactive nitrogen (Nr) compounds have different fates in the atmosphere due to differences in governing processes of physical transport, deposition and chemical transformation. Nr compounds addressed here include reduced nitrogen (NHx: ammonia (NH3) and its reaction product ammonium (NH4+)), oxidized nitrogen (NOy: nitrogen monoxide (NO) + nitrogen dioxide (NO2) and their reaction products) as well as organic nitrogen compounds (organic N). Pollution abatement strategies need to take into account these differences in the governing processes of these compounds when assessing their impact on ecosystem services, biodiversity, human health and climate. NOx (NO + NO2) emitted from traffic affects human health in urban areas where the presence of buildings increases the residence time in streets. In urban areas this leads to enhanced exposure of the population to NOx concentrations. NOx emissions have little impact on nearby ecosystems because of the small dry deposition rates of NOx. These compounds need to be converted into nitric acid (HNO3) before removal through deposition is efficient. HNO3 sticks quickly to any surface and is thereby either dry deposited or incorporated into aerosols as nitrate (NO3-). In contrast to NOx compounds, NH3 has potentially high impacts on ecosystems near the main agricultural sources of NH3 because of its large ground-level concentrations along with large dry deposition rates. Aerosol phase NH4+ and NO3- contribute significantly to background PM2.5 and PM10 (mass of aerosols with a diameter of less than 2.5 and 10 μm, respectively) with an impact on radiation balance as well as potentially on human health. Little is known quantitatively and qualitatively about organic N in the atmosphere, other than that it contributes a significant fraction of wet-deposited N, and is present in both gaseous and particulate forms in the atmosphere. Further studies are needed to characterize the sources, air chemistry and removal rates of organic N

  12. Origin of organic compounds in carbonaceous chondrites

    NASA Astrophysics Data System (ADS)

    Cronin, J. R.

    Carbonaceous chondrites, a class of primitive meteorite, have long been known to contain their complement of carbon largely in the form of organic, i.e., hydrocarbon-related, matter. Both discrete organic compounds and an insoluble, macromolecular material are present. Several characteristics of these materials provide evidence for their abiotic origin. The principal formation hypothesis have invoked chemistry occurring either in the solar nebula or on the parent body. However, recent stable isotope analyses of the meteorite carboxylic acids and amino acids indicate that they may be related to interstellar cloud compounds. These results suggest a formation scheme in which interstellar compounds were incorporated into the parent body and subsequently converted to the present suite of meteorite organics by the hydrothermal process believed to have formed the clay minerals of the meteorite matrix.

  13. Analyzing method on biogenic volatile organic compounds

    NASA Astrophysics Data System (ADS)

    Bai, J. H.; Wang, M. X.; Hu, F.; Greenberg, J. P.; Guenther, A. B.

    2002-02-01

    In order to analyze biogenic volatile organic compounds in the atmosphere, an automated gas chromatography is developed and employed at the laboratory of National Center for Atmospheric Research (NCAR) during January to July, 2000. A small refrigerator was used so as to remove water in the air sample from gas line, and get accurate concentrations of volatile organic compounds. At 5degreesC, good water removing efficiency can be obtained at controlled flow rate. Air samples were collected around the building of Mesa Lab. of NCAR and analyzed by this gas chromatography system. This paper reports this gas chromatography system and results of air samples. The experimental results show that this gas chromatography system has a good reproducibility and stability, and main interesting volatile organic compounds such as isoprene, monoterpenes have an evident diurnal variation.

  14. Catalyst for Oxidation of Volatile Organic Compounds

    NASA Technical Reports Server (NTRS)

    Wood, George M. (Inventor); Upchurch, Billy T. (Inventor); Schryer, David R. (Inventor); Davis, Patricia P. (Inventor); Kielin, Erik J. (Inventor); Brown, Kenneth G. (Inventor); Schyryer, Jacqueline L. (Inventor); DAmbrosia, Christine M. (Inventor)

    2000-01-01

    Disclosed is a process for oxidizing volatile organic compounds to carbon dioxide and water with the minimal addition of energy. A mixture of the volatile organic compound and an oxidizing agent (e.g. ambient air containing the volatile organic compound) is exposed to a catalyst which includes a noble metal dispersed on a metal oxide which possesses more than one oxidation state. Especially good results are obtained when the noble metal is platinum, and the metal oxide which possesses more than one oxidation state is tin oxide. A promoter (i.e., a small amount of an oxide of a transition series metal) may be used in association with the tin oxide to provide very beneficial results.

  15. Volatile and semivolatile organic compounds in laboratory ...

    EPA Pesticide Factsheets

    Speciated volatile organic compounds (VOCs) and organic fine particulate matter (PM2.5) mass emission factors were determined from laboratory peat fire experiments. Peat samples originated from two wildlife reserves located near the coast of North Carolina, U.S. Gas and particulate organics were quantified by gas chromatography/mass spectrometry and by high pressure liquid chromatography. Hazardous air pollutants (HAPs) accounted for a large fraction (~60 %) of the speciated VOC emissions from peat burning, including large contributions of acetaldehyde, formaldehyde, benzene, toluene, and chloromethane. Speciated organic PM2.5 mass was dominated by the following compound classes: organic acids, levoglucosan, n-alkanes, and n-alkenes. Emission factors for PM2.5 organic acids including n-alkanoic acids, n-alkenoic acids, n-alkanedioic acids, and aromatic acids were reported for the first time for peat burning, representing the largest fraction of organic carbon (OC) mass (11-12 %) of all speciated compound classes measured in this work. Levoglucosan contributed 2-3 % of the OC mass, while methoxyphenols represented 0.2-0.3 % of the OC mass on a carbon mass basis. Retene was the most abundant particulate phase polycyclic aromatic hydrocarbon. Total HAP VOC and particulate polycyclic aromatic hydrocarbon emissions from a 2008 peat wildfire in North Carolina were estimated, suggesting that peat fires can contribute a large fraction of state-wide HAP emissions. This p

  16. Chlorinated organic compounds in urban river sediments

    SciTech Connect

    Soma, Y.; Shiraishi, H.; Inaba, K.

    1995-12-31

    Among anthropogenic chemicals, many chlorinated organic compounds have been used as insecticides and detected frequently as contaminants in urban river sediments so far. However, the number and total amount of chemicals produced commercially and used are increasing year by year, though each amount of chemicals is not so high. New types of contaminants in the environment may be detected by the use of newly developed chemicals. Chlorinated organic compounds in the urban river sediments around Tokyo and Kyoto, large cities in Japan, were surveyed and recent trends of contaminants were studied. Contaminants of the river sediments in industrial areas had a variety, but PCB (polychlorinated biphenyls) was detected in common in industrial areas. Concentration of PCB related well to the number of factories on both sides of rivers, although the use of PCB was stopped 20 years ago. In domestic areas, Triclosan (5-chloro-2-(2,4-dichlorophenoxy)-phenol) and Triclocarban (3,4,4{prime}-trichlorocarbanilide)(both are contained in soap or shampoo for fungicides), p-dichlorobenzene (insecticides for wears) and TCEP(tris-chloroethyl phosphate) were detected. EOX(extracted organic halogen) in the sediments was 5 to 10 times of chlorinated organic compounds detected by GC/MS. Major part of organic halogen was suggested to be included in chlorinated organics formed by bleaching or sterilization.

  17. Volatile organic compounds from leaves litter.

    PubMed

    Isidorov, Valery; Jdanova, Maria

    2002-09-01

    Qualitative composition of volatile emissions of litter of five species of deciduous trees was investigated by GC-MS. The list of identified substances contains more than 70 organic compounds of various classes. It was established that the composition of components emitted by the litter into the gas phase greatly differs from that of essential oils extracted by hydrodistillation from turned leaves collected from trees during fall. It is suggested that most compounds found in litter emissions are products of vital activity of microorganisms decomposing it. The reported data indicate that after the vegetative period is over the decomposition processes of litter are important seasonal sources of reactive organic compounds under the forest canopy.

  18. Azodicarboxylates: synthesis and functionalization of organic compounds

    NASA Astrophysics Data System (ADS)

    Zhirov, A. M.; Aksenov, A. V.

    2014-06-01

    The data on transformations of dialkyl azodicarboxylates and their analogues involving various substrates are generalized. Nucleophilic addition and oxidation, pericyclic reactions and reactions occurring under the Mitsunobu reaction conditions are considered. Ample opportunities for application of these compounds in fine organic synthesis are shown. The bibliography includes 245 references. Dedicated to Academician B A Trofimov on the occasion of his 75th birthday.

  19. Organic nitrogen chemistry during low-grade metamorphism

    USGS Publications Warehouse

    Boudou, J.-P.; Schimmelmann, A.; Ader, M.; Mastalerz, Maria; Sebilo, M.; Gengembre, L.

    2008-01-01

    Most of the organic nitrogen (Norg) on Earth is disseminated in crustal sediments and rocks in the form of fossil nitrogen-containing organic matter. The chemical speciation of fossil Norg within the overall molecular structure of organic matter changes with time and heating during burial. Progressive thermal evolution of organic matter involves phases of enhanced elimination of Norg and ultimately produces graphite containing only traces of nitrogen. Long-term chemical and thermal instability makes the chemical speciation of Norg a valuable tracer to constrain the history of sub-surface metamorphism and to shed light on the subsurface biogeochemical nitrogen cycle and its participating organic and inorganic nitrogen pools. This study documents the evolutionary path of Norg speciation, transformation and elimination before and during metamorphism and advocates the use of X-ray photoelectron spectroscopy (XPS) to monitor changes in Norg speciation as a diagnostic tool for organic metamorphism. Our multidisciplinary evidence from XPS, stable isotopes, traditional quantitative coal analyses, and other analytical approaches shows that at the metamorphic onset Norg is dominantly present as pyrrolic and pyridinic nitrogen. The relative abundance of nitrogen substituting for carbon in condensed, partially aromatic systems (where N is covalently bonded to three C atoms) increases exponentially with increasing metamorphic grade, at the expense of pyridinic and pyrrolic nitrogen. At the same time, much Norg is eliminated without significant nitrogen isotope fractionation. The apparent absence of Rayleigh-type nitrogen isotopic fractionation suggests that direct thermal loss of nitrogen from an organic matrix does not serve as a major pathway for Norg elimination. Instead, we propose that hot H, O-containing fluids or some of their components gradually penetrate into the carbonaceous matrix and eliminate Norg along a progressing reaction front, without causing nitrogen

  20. Assessment of Tri- and Hexavalent Chromium Phytotoxicity on Oats (Avena sativa L.) Biomass and Content of Nitrogen Compounds.

    PubMed

    Wyszkowski, Mirosław; Radziemska, Maja

    2013-07-01

    The purpose of this study was to determine the effect of soil contamination with tri- and hexavalent chromium and soil application of compost, zeolite, and CaO on the mass of oats and content of nitrogen compounds in different organs of oats. The oats mass and content of nitrogen compounds in the crop depended on the type and dose of chromium and alleviating substances incorporated to soil. In the series without neutralizing substances, Cr(VI), unlike Cr(III), had a negative effect on the growth and development of oats. The highest doses of Cr(VI) and Cr(III) stimulated the accumulation of total nitrogen but depressed the content of N-NO3(-) in most of organs of oats. Among the substances added to soil in order to alleviate the negative impact of Cr (VI) on the mass of plants, compost had a particularly beneficial effect on the growth and development of oats. The application of compost, zeolite, and CaO to soil had a stronger effect on the content of nitrogen compounds in grain and straw than in roots. Soil enrichment with either of the above substances usually raised the content of nitrogen compounds in oats grain and straw, but decreased it in roots.

  1. Microwave spectra of some sulfur and nitrogen compounds. [for chemical analysis

    NASA Technical Reports Server (NTRS)

    White, W. F.

    1974-01-01

    A computer-controlled microwave spectrometer was used to catalog reference spectra for chemical analysis. The apparatus, software, and experimental procedures are described. Tables of absorption frequencies, peak absorption coefficients, and integrated intensities are included for 13 sulfur compounds, 14 nitrogen compounds, and 1 compound containing both sulfur and nitrogen. The frequency range covered was 26,500 to 40,000 MHz for most compounds and 18,000 to 40,000 MHz for some.

  2. [Role of Anammox Bacteria in Removal of Nitrogen Compounds from Wastewater].

    PubMed

    Kallistovaa, A Yu; Dorofeev, A G; Nikolaev, Yu A; Kozlov, M N; Kevbrina, M V; Pimenov, N V

    2016-01-01

    The review deals with the unique microbial group responsible for anaerobic ammonium oxidation with nitrite (anammox), and with the role of this process in development of the biotechnology for removal of nitrogen compounds from wastewater. The history of the study of this process is briefly related. Up-to date knowledge on the intracellular organization, energy metabolism, growth stoichiometry, and physiology of anammox bacteria is described, and the main methods for cultivation of these microorganisms are characterized. Special attention is paid to the problems associated with practical application of anammox bacteria, which result from their extremely slow growth, the absence of pure cultures, and the interaction with other microbial groups.

  3. Emission and deposition of Nitrogen compounds in West Africa

    NASA Astrophysics Data System (ADS)

    Delon, C.; Galy-Lacaux, C.; Adon, M.; Liousse, C.

    2010-12-01

    The atmospheric nitrogen budget depends on emission and deposition fluxes both as reduced and oxidized compounds. In West African ecosystems, data are scarce, and establishing a N budget is not an easy task. This work aims at linking data from diverse origins (surface, aircraft measurements, satellite data, modelling) to estimate emissions and deposition of N compounds in dry and wet savannas of West Africa, and to study their impact on atmospheric chemistry. In remote areas like in the Sahel, N oxidised compounds emissions are dominated by NO biogenic emissions from soils. N emissions from anthropogenic sources (biomass burning, domestic fires, fossil fuel) are less important, due to the low quantity of vegetation, and to the remoteness of big cities. N reduced compounds emissions are dominated by the release of NH3 from cattle dung. Biogenic NO emissions from soils have a direct impact on NOx and O3 concentration increase in the lower troposphere, as shown by results from aircraft and surface measurements, and from modelling (coupled dynamics/chemistry MESONH-C model, with on line emission derived from a neural network algorithm, where the NO flux is dependent on water field pore space, surface and deep soil temperature, sand percentage, pH, fertilization rate and wind speed), in the area of Niamey (Niger) in August 2006. In a second part of this work, estimated emissions of both oxidised and reduced N compounds are compared to estimate dry and wet deposition fluxes for the year 2006 in the Sahel region. The dry deposition flux is the product of modelled dry deposition velocity and the measured concentration. Concentrations have been measured in 3 stations located in dry savanna ecosystem) within the IDAF (IGAC/DEBITS/Africa) network, and dry deposition velocities have been modelled with the surface model ISBA. A first tentative of budget has been calculated for the year 2006, trying to integrate all potentially known sources and sinks in the region. Finally, the

  4. Nonvolatile organic compounds in treated waters.

    PubMed Central

    Watts, C D; Crathorne, B; Fielding, M; Killops, S D

    1982-01-01

    Over the past decade much information has been published on the analysis of organics extracted from treated water. Certain of these organics have been shown to be by-products of the chlorination disinfection process and to possess harmful effects at high concentrations. This has resulted in increased interest in alternative disinfection processes, particularly ozonation. The data on organics had been largely obtained by using gas chromatography-mass spectrometry, which is only capable of analyzing, at best, 20% of the organics present in treated water. Research in key areas such as mutagenicity testing of water and characterization of chlorination and ozonation by-products has emphasized the need for techniques suitable for analysis of the remaining nonvolatile organics. Several methods for the isolation of nonvolatile organics have been evaluated and, of these, freeze-drying followed by methanol extraction appears the most suitable. Reverse-phase HPLC was used for separation of the methanol extract, but increased resolution for separation of the complex mixtures present is desirable. In this context, high resolution size exclusion chromatography shows promise. Characterization of separated nonvolatiles is possible by the application of state-of-the-art mass spectrometric techniques. Results obtained by these techniques have shown that the nonvolatile organic fraction of chlorinated drinking water consists of many discrete compounds. Among these, some of the chlorinated compounds are almost certainly by-products of disinfection. Studies of the by-products of ozonation of fulvic and humic acids isolated from river waters have indicated a similar proportion of nonvolatile organics. Further, ozonation can result in the release of compounds that are trapped in the macromolecules. PMID:6759110

  5. Enantiomer distribution of major chiral volatile organic compounds in selected types of herbal honeys.

    PubMed

    Pažitná, Alexandra; Džúrová, Jana; Spánik, Ivan

    2014-10-01

    In this article, volatile organic compounds in 14 honey samples (rosemary, eucalyptus, orange, thyme, sage, and lavender) were identified. Volatile organic compounds were extracted using a solid phase microextraction method followed by gas chromatography connected with mass spectrometry analysis. The studied honey samples were compared based on their volatile organic compounds composition. In total, more than 180 compounds were detected in the studied samples. The detected compounds belong to various chemical classes such as terpenes, alcohols, acids, aldehydes, ketones, esters, norisoprenoids, benzene and furane derivatives, and organic compounds containing sulfur and nitrogen heteroatom. Ten chiral compounds (linalool, trans-linalool oxide, cis-linalool oxide, 4-terpineol, α-terpineol, hotrienol, and four stereoisomers of lilac aldehydes) were selected for further chiral separation.

  6. Organic photosensitive devices using subphthalocyanine compounds

    SciTech Connect

    Rand, Barry; Forrest, Stephen R.; Mutolo, Kristin L.; Mayo, Elizabeth; Thompson, Mark E.

    2011-07-05

    An organic photosensitive optoelectronic device, having a donor-acceptor heterojunction of a donor-like material and an acceptor-like material and methods of making such devices is provided. At least one of the donor-like material and the acceptor-like material includes a subphthalocyanine, a subporphyrin, and/or a subporphyrazine compound; and/or the device optionally has at least one of a blocking layer or a charge transport layer, where the blocking layer and/or the charge transport layer includes a subphthalocyanine, a subporphyrin, and/or a subporphyrazine compound.

  7. Nitrate Remediation of Soil and Groundwater Using Phytoremediation: Transfer of Nitrogen Containing Compounds from the Subsurface to Surface Vegetation

    NASA Astrophysics Data System (ADS)

    Nelson, Sheldon

    2013-04-01

    Nitrate Remediation of Soil and Groundwater Using Phytoremediation: Transfer of Nitrogen Containing Compounds from the Subsurface to Surface Vegetation Sheldon Nelson Chevron Energy Technology Company 6001 Bollinger Canyon Road San Ramon, California 94583 snne@chevron.com The basic concept of using a plant-based remedial approach (phytoremediation) for nitrogen containing compounds is the incorporation and transformation of the inorganic nitrogen from the soil and/or groundwater (nitrate, ammonium) into plant biomass, thereby removing the constituent from the subsurface. There is a general preference in many plants for the ammonium nitrogen form during the early growth stage, with the uptake and accumulation of nitrate often increasing as the plant matures. The synthesis process refers to the variety of biochemical mechanisms that use ammonium or nitrate compounds to primarily form plant proteins, and to a lesser extent other nitrogen containing organic compounds. The shallow soil at the former warehouse facility test site is impacted primarily by elevated concentrations of nitrate, with a minimal presence of ammonium. Dissolved nitrate (NO3-) is the primary dissolved nitrogen compound in on-site groundwater, historically reaching concentrations of 1000 mg/L. The initial phases of the project consisted of the installation of approximately 1750 trees, planted in 10-foot centers in the areas impacted by nitrate and ammonia in the shallow soil and groundwater. As of the most recent groundwater analytical data, dissolved nitrate reductions of 40% to 96% have been observed in monitor wells located both within, and immediately downgradient of the planted area. In summary, an evaluation of time series groundwater analytical data from the initial planted groves suggests that the trees are an effective means of transfering nitrogen compounds from the subsurface to overlying vegetation. The mechanism of concentration reduction may be the uptake of residual nitrate from the

  8. Climate impacts of biogenic organic compounds

    NASA Astrophysics Data System (ADS)

    Sengupta, Kamalika; Gordon, Hamish; Almeida, Joao; Rap, Alex; Scott, Catherine; Pringle, Kirsty; Carslaw, Ken

    2016-04-01

    Currently the most uncertain driver of climate change, impact of anthropogenic aerosols on earth's radiative balance depends significantly on estimates of cloud condensation nuclei (CCN), representation of the pre-industrial atmosphere among others. Nearly 90% of aerosols in the tropics are organic in nature of which a major part comes from biogenic sources. About 45% of the CCN in the atmosphere are formed in-situ via nucleation. Understanding the role of biogenic organic compounds in particle formation and their subsequent growth is hence imperative in order to quantify the climate impact of aerosols. The CLOUD experiment at CERN, which measures particle formation and growth rates in a uniquely clean chamber under atmospherically relevant conditions, found evidence of a nucleation mechanism involving only biogenic organic compounds. This mechanism significantly changes our pre-industrial estimates. The experimental results have been parameterized and included in a global aerosol microphysics model, GLOMAP, to quantify the impact of pure biogenic nucleation on CCN formation and their climatic impact. Further the treatment of secondary organic compounds in GLOMAP has been improved and the sensitivity of our estimates of radiative forcing to the same has been evaluated.

  9. Predicting the octanol solubility of organic compounds.

    PubMed

    Admire, Brittany; Yalkowsky, Samuel H

    2013-07-01

    The molar octanol solubility of an organic nonelectrolytes can be reasonably predicted solely from its melting point provided that its liquid (or a hypothetical super-cooled liquid) form is miscible with octanol. The aim of this work is to develop criteria to determine if the real or hypothetical liquid form of a given compound will be miscible with octanol based on its molar volume and solubility parameter. Fortunately, most organic compounds (including most drugs) conform to the criteria for complete liquid miscibility, and therefore have solubilities that are proportional to their melting points. The results show that more than 95% of the octanol solubilities studied are predicted with an error of less than 1 logarithmic unit.

  10. Identification and Quantification of Volatile Organic Compounds at a Dairy

    NASA Astrophysics Data System (ADS)

    Filipy, J.; Mount, G.; Westberg, H.; Rumburg, B.

    2003-12-01

    Livestock operations in the United States are an escalating environmental concern. The increasing density of livestock within a farm results in an increased emission of odorous gases, which have gained considerable attention by the public in recent years (National Research Council (NRC), 2002). Odorous compounds such as ammonia (NH3), volatile organic compounds (VOC's), and hydrogen sulfide (H2S) were reported to have a major effect on the quality of life of local residents living near livestock facilities (NRC, 2002). There has been little data collected related to identification and quantification of gaseous compounds collected from open stall dairy operations in the United States. The research to be presented identifies and quantifies VOCs produced from a dairy operation that contribute to odor and other air quality problems. Many different VOCs were identified in the air downwind of an open lactating cow stall area and near a waste lagoon at the Washington State University dairy using Gas Chromatography Mass Spectroscopy (GC-MS) analysis techniques. Identified compounds were very diverse and included many alcohols, aldehydes, amines, aromatics, esters, ethers, a fixed gas, halogenated hydrocarbons, hydrocarbons, ketones, other nitrogen containing compounds, sulfur containing compounds, and terpenes. The VOCs directly associated with cattle waste were dependent on ambient temperature, with the highest emissions produced during the summer months. Low to moderate wind speeds were ideal for VOC collection. Concentrations of quantified compounds were mostly below odor detection thresholds found in the literature, however the combined odor magnitude of the large number of compounds detected was most likely above any minimum detection threshold.

  11. Organic Compounds in Star Forming Regions

    NASA Astrophysics Data System (ADS)

    Kochina, O.; Wiebe, D.

    2014-09-01

    The influence of complex dust composition on the general chemical evolution of a prestellar core and the content of complex organic compounds is studied. It is shown that various component groups respond differently to the presence of a small dust population. At early stages the difference is determined primarily by changes in the balance of photo processes due to effective absorption of ultraviolet photons by small dust grains of the second population and collisional reactions with dust particles. At later stages differences are also caused by the growing dominance of additional reaction channels related to surface organic synthesis.

  12. Organic compounds in star forming regions.

    PubMed

    Kochina, O; Wiebe, D

    2014-09-01

    The influence of complex dust composition on the general chemical evolution of a prestellar core and the content of complex organic compounds is studied. It is shown that various component groups respond differently to the presence of a small dust population. At early stages the difference is determined primarily by changes in the balance of photo processes due to effective absorption of ultraviolet photons by small dust grains of the second population and collisional reactions with dust particles. At later stages differences are also caused by the growing dominance of additional reaction channels related to surface organic synthesis.

  13. Metabolic Reactions among Organic Sulfur Compounds

    NASA Technical Reports Server (NTRS)

    Schulte, M.; Rogers, K.

    2005-01-01

    Sulfur is central to the metabolisms of many organisms that inhabit extreme environments. Numerous authors have addressed the energy available from a variety of inorganic sulfur redox pairs. Less attention has been paid, however, to the energy required or gained from metabolic reactions among organic sulfur compounds. Work in this area has focused on the oxidation of alkyl sulfide or disulfide to thiol and formaldehyde, e.g. (CH3)2S + H2O yields CH3SH + HCHO + H2, eventually resulting in the formation of CO2 and SO4(-2). It is also found that reactions among thiols and disulfides may help control redox disequilibria between the cytoplasm and the periplasm. Building on our earlier efforts for thiols, we have compiled and estimated thermodynamic properties for alkyl sulfides. We are investigating metabolic reactions among various sulfur compounds in a variety of extreme environments, ranging from sea floor hydrothermal systems to organic-rich sludge. Using thermodynamic data and the revised HKF equation of state, along with constraints imposed by the geochemical environments sulfur-metabolizing organisms inhabit, we are able to calculate the amount of energy available to these organisms.

  14. Quantitative analysis of nitrogen containing compounds in microalgae based bio-oils using comprehensive two-dimensional gas-chromatography coupled to nitrogen chemiluminescence detector and time of flight mass spectrometer.

    PubMed

    Toraman, Hilal E; Franz, Kristina; Ronsse, Frederik; Van Geem, Kevin M; Marin, Guy B

    2016-08-19

    Insight in the composition of the algae derived bio-oils is crucial for the development of efficient conversion processes and better upgrading strategies for microalgae. Comprehensive two-dimensional gas chromatography (GC×GC) coupled to nitrogen chemiluminescence detector (NCD) and time-of-flight mass spectrometer (TOF-MS) allows to obtain the detailed quantitative composition of the nitrogen containing compounds in the aqueous and the organic fraction of fast pyrolysis bio-oils from microalgae. Normal phase (apolar×mid-polar) and reverse phase column (polar×apolar) combination are investigated to optimize the separation of the detected nitrogen containing compounds. The reverse phase column combination gives the most detailed information in terms of the nitrogen containing compounds. The combined information from the GC×GC-TOF-MS (qualitative) and GC×GC-NCD (quantitative) with the use of a well-chosen internal standard, i.e. caprolactam, enables the identification and quantification of nitrogen containing compounds belonging to 13 different classes: amines, imidazoles, amides, imides, nitriles, pyrazines, pyridines, indoles, pyrazoles, pyrimidines, quinolines, pyrimidinediones and other nitrogen containing compounds which were not assigned to a specific class. The aqueous fraction mostly consists of amines (4.0wt%) and imidazoles (2.8wt%) corresponding to approximately 80wt% of the total identified nitrogen containing compounds. On the other hand, the organic fraction shows a more diverse distribution of nitrogen containing compounds with the majority of the compounds quantified as amides (3.0wt%), indoles (2.0wt%), amines (1.7wt%) and imides (1.3wt%) corresponding to approximately 65wt% of the total identified nitrogen containing compounds.

  15. Compositional space boundaries for organic compounds.

    PubMed

    Lobodin, Vladislav V; Marshall, Alan G; Hsu, Chang Samuel

    2012-04-03

    An upper elemental compositional boundary for fossil hydrocarbons has previously been established as double-bond equivalents (i.e., DBE = rings plus double bonds) not exceeding 90% of the number of carbons. For heteroatom-containing fossil compounds, the 90% rule still applies if each N atom is counted as a C atom. The 90% rule eliminates more than 10% of the possible elemental compositions at a given mass for fossil database molecules. However, some synthetic compounds can fall outside the upper boundary defined for naturally occurring compounds. Their inclusion defines an "absolute" upper boundary as DBE (rings plus double bonds to carbon) equal to carbon number plus one, and applies to all organic compounds including fullerenes and other molecules containing no hydrogen. Finally, the DBE definition can fail for molecules with particular atomic valences. Therefore, we also present a generalized DBE definition that includes atomic valence to enable calculation of the correct total number of rings, double bonds, and triple bonds for heteroatom-containing compounds.

  16. Formation of highly oxidized multifunctional organic compounds from anthropogenic volatile organic compounds

    NASA Astrophysics Data System (ADS)

    Molteni, Ugo; Baltensperger, Urs; Bianchi, Federico; Dommen, Josef; El Haddad, Imad; Frege, Carla; Klein, Felix; Rossi, Michel

    2016-04-01

    Recent studies have shown that highly oxidized multifunctional organic compounds (HOMs) from biogenic volatile organic compounds are important for new particle formation and early particle growth (e.g., Ehn et al., 2014). The formation mechanism has extensively been studied for biogenic precursors like alpha-pinene and was shown to proceed through an initial reaction with either OH radicals or ozone followed by radical propagation in a mechanism that involves O2 attack and hydrogen abstraction (Crounse et al., 2013). While the same processes can be expected for anthropogenic volatile organic compounds (AVOC), few studies have investigated these so far. Here we present the formation of HOMs from a variety of aromatic compounds after reaction with OH. All the compounds analyzed show HOM formation. AVOC could therefore play an important role in new particle formation events that have been detected in urban areas. References Crounse, J.D. et al., Autoxidation of organic compounds in the atmosphere. J. Phys.Chem. Lett. 4, 3513-3520 (2013). Ehn, M., et al. A large source of low-volatility secondary organic aerosol, Nature 506, 476-479 (2014).

  17. Sources of organic nitrogen at the serpentinite-hosted Lost City hydrothermal field.

    PubMed

    Lang, S Q; Früh-Green, G L; Bernasconi, S M; Butterfield, D A

    2013-03-01

    The reaction of ultramafic rocks with water during serpentinization at moderate temperatures results in alkaline fluids with high concentrations of reduced chemical compounds such as hydrogen and methane. Such environments provide unique habitats for microbial communities capable of utilizing these reduced compounds in present-day and, possibly, early Earth environments. However, these systems present challenges to microbial communities as well, particularly due to high fluid pH and possibly the availability of essential nutrients such as nitrogen. Here we investigate the source and cycling of organic nitrogen at an oceanic serpentinizing environment, the Lost City hydrothermal field (30°N, Mid-Atlantic Ridge). Total hydrolizable amino acid (THAA) concentrations in the fluids range from 736 to 2300 nm and constitute a large fraction of the dissolved organic carbon (2.5-15.1%). The amino acid distributions, and the relative concentrations of these compounds across the hydrothermal field, indicate they most likely derived from chemolithoautotrophic production. Previous studies have identified the presence of numerous nitrogen fixation genes in the fluids and the chimneys. Organic nitrogen in actively venting chimneys has δ(15) N values as low as 0.1‰ which is compatible with biological nitrogen fixation. Total hydrolizable amino acids in the chimneys are enriched in (13) C by 2-7‰ compared to bulk organic matter. The distribution and absolute δ(13) C(THAA) values are compatible with a chemolithoautotrophic source, an attribution also supported by molar organic C/N ratios in most active chimneys (4.1-5.5) which are similar to those expected for microbial communities. In total, these data indicate nitrogen is readily available to microbial communities at Lost City.

  18. Carbon and nitrogen isotopic signatures and nitrogen profile to identify adulteration in organic fertilizers.

    PubMed

    Verenitch, Sergei; Mazumder, Asit

    2012-08-29

    Recently it has been shown that stable isotopes of nitrogen can be used to discriminate between organic and synthetic fertilizers, but the robustness of the approach is questionable. This work developed a comprehensive method that is far more robust in identifying an adulteration of organic nitrogen fertilizers. Organic fertilizers of various types (manures, composts, blood meal, bone meal, fish meal, products of poultry and plant productions, molasses and seaweed based, and others) available on the North American market were analyzed to reveal the most sensitive criteria as well as their quantitative ranges, which can be used in their authentication. Organic nitrogen fertilizers of known origins with a wide δ(15)N range between -0.55 and 28.85‰ (n = 1258) were characterized for C and N content, δ(13)C, δ(15)N, viscosity, pH, and nitrogen profile (urea, ammonia, organic N, water insoluble N, and NO3). A statistically significant data set of characterized unique organic nitrogen fertilizers (n = 335) of various known origins has been assembled. Deliberately adulterated samples of different types of organic fertilizers mixed with synthetic fertilizers at a wide range of proportions have been used to develop the quantitative critical characteristics of organic fertilizers as the key indicators of their adulteration. Statistical analysis based on the discriminant functions of the quantitative critical characteristics of organic nitrogen fertilizers from 14 different source materials revealed a very high average rate of correct classification. The developed methodology has been successfully used as a source identification tool for numerous commercial nitrogen fertilizers available on the North American market.

  19. Impact of fermentation on nitrogenous compounds of cocoa beans (Theobroma cacao L.) from various origins.

    PubMed

    Hue, C; Gunata, Z; Breysse, A; Davrieux, F; Boulanger, R; Sauvage, F X

    2016-02-01

    Tangential filtration technique was used to separate and quantify three different fractions of nitrogenous compounds depending on their molecular size, during cocoa fermentation. On every phenotype and origin analyzed, protein profile of non-fermented samples was similar. During fermentation course, proteins get degraded with a concomitant increase in amino acids content. Peptides between 3 and 10 kDa were observed at low levels. A strong correlation between amino acids and ammonia nitrogen, a fermentation marker was found. Attention was drawn on each fraction, and enabled to point out other phenomenon occurring during fermentation. The migration of some nitrogenous compounds towards the bean shell during fermentation was demonstrated. Acetone treatment of cocoa powder prior to SDS-PAGE led to losses of nitrogenous compounds. This result gives clues on the tanning phenomenon carried out by polyphenols on nitrogenous compounds, phenomenon which increases during fermentation.

  20. Self assembly properties of primitive organic compounds

    NASA Technical Reports Server (NTRS)

    Deamer, D. W.

    1991-01-01

    A central event in the origin of life was the self-assembly of amphiphilic, lipid-like compounds into closed microenvironments. If a primitive macromolecular replicating system could be encapsulated within a vesicular membrane, the components of the system would share the same microenvironment, and the result would be a step toward true cellular function. The goal of our research has been to determine what amphiphilic molecules might plausibly have been available on the early Earth to participate in the formation of such boundary structures. To this end, we have investigated primitive organic mixtures present in carbonaceous meteorites such as the Murchison meteorite, which contains 1-2 percent of its mass in the form of organic carbon compounds. It is likely that such compounds contributed to the inventory of organic carbon on the prebiotic earth, and were available to participate in chemical evolution leading to the emergence of the first cellular life forms. We found that Murchison components extracted into non-polar solvent systems are surface active, a clear indication of amphiphilic character. One acidic fraction self-assembles into vesicular membranes that provide permeability barriers to polar solutes. Other evidence indicates that the membranes are bimolecular layers similar to those formed by contemporary membrane lipids. We conclude that bilayer membrane formation by primitive amphiphiles on the early Earth is feasible. However, only a minor fraction of acidic amphiphiles assembles into bilayers, and the resulting membranes require narrowly defined conditions of pH and ionic composition to be stable. It seems unlikely, therefore, that meteoritic infall was a direct source of membrane amphiphiles. Instead, the hydrocarbon components and their derivatives more probably would provide an organic stock available for chemical evolution. Our current research is directed at possible reactions which would generate substantial quantities of membranogenic

  1. Soil organic nitrogen mineralization across a global latitudinal gradient

    NASA Astrophysics Data System (ADS)

    Jones, D. L.; Kielland, K.; Sinclair, F. L.; Dahlgren, R. A.; Newsham, K. K.; Farrar, J. F.; Murphy, D. V.

    2009-03-01

    Understanding and accurately predicting the fate of carbon and nitrogen in the terrestrial biosphere remains a central goal in ecosystem science. Amino acids represent a key pool of C and N in soil, and their availability to plants and microorganisms has been implicated as a major driver in regulating ecosystem functioning. Because of potential differences in biological diversity and litter quality, it has been thought that soils from different latitudes and plant communities may possess intrinsically different capacities to perform key functions such as the turnover of amino acids. In this study we measured the soil solution concentration and microbial mineralization of amino acids in soils collected from 40 latitudinal points from the Arctic through to Antarctica. Our results showed that soil solution amino acid concentrations were relatively similar between sites and not strongly related to latitude. In addition, when constraints of temperature and moisture were removed, we demonstrate that soils worldwide possess a similar innate capacity to rapidly mineralize amino acids. Similarly, we show that the internal partitioning of amino acid-C into catabolic and anabolic processes is conservative in microbial communities and independent of global position. This supports the view that the conversion of high molecular weight (MW) organic matter to low MW compounds is the rate limiting step in organic matter breakdown in most ecosystems.

  2. Sources and source processes of organic nitrogen aerosols in the atmosphere

    NASA Astrophysics Data System (ADS)

    Erupe, Mark E.

    The research in this dissertation explored the sources and chemistry of organic nitrogen aerosols in the atmosphere. Two approaches were employed: field measurements and laboratory experiments. In order to characterize atmospheric aerosol, two ambient studies were conducted in Cache Valley in Northern Utah during strong winter inversions of 2004 and 2005. The economy of this region is heavily dependent on agriculture. There is also a fast growing urban population. Urban and agricultural emissions, aided by the valley geography and meteorology, led to high concentrations of fine particles that often exceeded the national ambient air quality standards. Aerosol composition was dominated by ammonium nitrate and organic species. Mass spectra from an aerosol mass spectrometer revealed that the organic ion peaks were consistent with reduced organic nitrogen compounds, typically associated with animal husbandry practices. Although no direct source characterization studies have been undertaken in Cache Valley with an aerosol mass spectrometer, spectra from a study at a swine facility in Ames, Iowa, did not show any evidence of reduced organic nitrogen species. This, combined with temporal and diurnal characteristics of organic aerosol peaks, was a pointer that the organic nitrogen species in Cache Valley likely formed from secondary chemistry. Application of multivariate statistical analyses to the organic aerosol spectra further supported this hypothesis. To quantify organic nitrogen signals observed in ambient studies as well as understand formation chemistry, three categories of laboratory experiments were performed. These were calibration experiments, smog chamber studies, and an analytical method development. Laboratory calibration experiments using standard calibrants indicated that quantifying the signals from organic nitrogen species was dependent on whether they formed through acid-base chemistry or via secondary organic aerosol pathway. Results from smog chamber

  3. Compound-specific stable isotopes of organic compounds from lake sediments track recent environmental changes in an alpine ecosystem, Rocky Mountain National Park, Colorado

    USGS Publications Warehouse

    Enders, S.K.; Pagani, M.; Pantoja, S.; Baron, J.S.; Wolfe, A.P.; Pedentchouk, N.; Nunez, L.

    2008-01-01

    Compound-specific nitrogen, carbon, and hydrogen isotope records from sediments of Sky Pond, an alpine lake in Rocky Mountain National Park (Colorado, United States of America), were used to evaluate factors contributing to changes in diatom assemblages and bulk organic nitrogen isotope records identified in lake sediments across Colorado, Wyoming, and southern Montana. Nitrogen isotopic records of purified algal chlorins indicate a substantial shift in nitrogen cycling in the region over the past ???60 yr. Temporal changes in the growth characteristics of algae, captured in carbon isotope records in and around Sky Pond, as well as a -60??? excursion in the hydrogen isotope composition of algal-derived palmitic acid, are coincident with changes in nitrogen cycling. The confluence of these trends is attributed to an increase in biologically available nitrogenous compounds caused by an expansion of anthropogenic influences and temporal changes in catchment hydrology and nutrient delivery associated with meltwater dynamics. ?? 2008, by the American Society of Limnology and Oceanography, Inc.

  4. Biogenic volatile organic compounds - small is beautiful

    NASA Astrophysics Data System (ADS)

    Owen, S. M.; Asensio, D.; Li, Q.; Penuelas, J.

    2012-12-01

    While canopy and regional scale flux measurements of biogenic volatile organic compounds (bVOCs) are essential to obtain an integrated picture of total compound reaching the atmosphere, many fascinating and important emission details are waiting to be discovered at smaller scales, in different ecological and functional compartments. We concentrate on bVOCs below ground to <2m above ground level. Emissions at leaf scale are well documented and widely presented, and are not discussed here. Instead we describe some details of recent research on rhizosphere bVOCs, and bVOCs associated with pollination of flowers. Although bVOC emissions from soil surfaces are small, bVOCs are exuded by roots of some plant species, and can be extracted from decaying litter. Naturally occurring monoterpenes in the rhizosphere provide a specialised carbon source for micro-organisms, helping to define the micro-organism community structure, and impacting on nutrient cycles which are partly controlled by microorganisms. Naturally occurring monoterpenes in the soil system could also affect the aboveground structure of ecosystems because of their role in plant defence strategies and as mediating chemicals in allelopathy. A gradient of monoterpene concentration was found in soil around Pinus sylvestris and Pinus halepensis, decreasing with distance from the tree. Some compounds (α-pinene, sabinene, humulene and caryophyllene) in mineral soil were linearly correlated with the total amount of each compound in the overlying litter, indicating that litter might be the dominant source of these compounds. However, α-pinene did not fall within the correlation, indicating a source other than litter, probably root exudates. We also show that rhizosphere bVOCs can be a carbon source for soil microbes. In a horizontal gradient from Populus tremula trees, microbes closest to the tree trunk were better enzymatically equipped to metabolise labeled monoterpene substrate. Monoterpenes can also increase the

  5. Polyphenols, fungal enzymes, and the fate of organic nitrogen in a Californian pygmy forest

    NASA Astrophysics Data System (ADS)

    Slessarev, E.

    2011-12-01

    Polyphenols are a diverse family of plant secondary compounds which may influence litter decay and soil nutrient turnover. The "short circuit" hypothesis for polyphenol function proposes that polyphenolic compounds provision plants with nitrogen in nutrient-poor soils by facilitating the accumulation of organic nitrogen in soil humus. By binding peptides, polyphenols may sequester nitrogen in a bank of recalcitrant organic matter, granting competitive advantage to plants with the mycorrhizal fungi most capable of recapturing the tightly bound organic nitrogen. Specifically, fungi may retrieve nitrogen from polyphenol-peptide complexes with an extracellular enzyme, polyphenol oxidase (PPO). In order to evaluate the "short circuit" hypothesis, I measured soil PPO activity during four seasons in the Mendocino "ecological staircase," a soil age-gradient consisting of a series of wave-cut terraces along stretches of the northern California coast. Stunted, pygmy-forest plants growing in the nutrient-poor soils of the older marine terraces produce more polyphenols than their con-specifics on nutrient-rich younger terraces, potentially influencing PPO facilitated nitrogen cycling. I found that PPO activity reached its maximum in the younger terrace forest during the spring, achieving levels nearly twice as high as those observed on the younger terrace in other seasons and in the older terrace forest year-round. In both terraces, PPO activity was greatest in the organic humus at the soil surface, decreasing dramatically in the lower mineral horizon. When PPO activity reached its maximum in the younger terrace, I found that soil polyphenol content positively correlated (Rsq=0.63) with enzyme activity, suggesting that polyphenols might induce enzyme production. However, in the tannin-rich soil of the pygmy forest on the older terrace, enzyme activity remained low, and was most strongly correlated with soil moisture. The results do not support the hypothesis that nutrient

  6. Molecular signature of organic nitrogen in septic-impacted groundwater

    USGS Publications Warehouse

    Arnold, William A.; Longnecker, Krista; Kroeger, Kevin D.; Kujawinski, Elizabeth B.

    2014-01-01

    Dissolved inorganic and organic nitrogen levels are elevated in aquatic systems due to anthropogenic activities. Dissolved organic nitrogen (DON) arises from various sources, and its impact could be more clearly constrained if specific sources were identified and if the molecular-level composition of DON were better understood. In this work, the pharmaceutical carbamazepine was used to identify septic-impacted groundwater in a coastal watershed. Using ultrahigh resolution mass spectrometry data, the nitrogen-containing features of the dissolved organic matter in septic-impacted and non-impacted samples were compared. The septic-impacted groundwater samples have a larger abundance of nitrogen-containing formulas. Impacted samples have additional DON features in the regions ascribed as ‘protein-like’ and ‘lipid-like’ in van Krevelen space and have more intense nitrogen-containing features in a specific region of a carbon versus mass plot. These features are potential indicators of dissolved organic nitrogen arising from septic effluents, and this work suggests that ultrahigh resolution mass spectrometry is a valuable tool to identify and characterize sources of DON.

  7. Atmospheric Deposition of Soluble Organic Nitrogen due to Biomass Burning

    NASA Astrophysics Data System (ADS)

    Ito, A.; Lin, G.; Penner, J. E.

    2014-12-01

    Atmospheric deposition of reactive nitrogen (N) species from large fires may contribute to enrichment of nutrients in aquatic ecosystems. Here we use an atmospheric chemistry transport model to investigate the supply of soluble organic nitrogen (ON) from open biomass burning to the ocean. The model results show that the annual deposition rate of soluble ON to the oceans is increased globally by 13% with the increase being particularly notable over the coastal water downwind from the source regions. The estimated deposition of soluble ON due to haze events from the secondary formation is more than half of that from the primary sources. We examine the secondary formation of particulate C-N compounds (e.g., imidazole) from the reactions of glyoxal and methylglyoxal with atmospheric ammonium in wet aerosols and upon cloud evaporation. These ON sources result in a significant contribution to the open ocean, suggesting that atmospheric processing in aqueous phase may have a large effect. We compare the soluble ON concentration in aerosols with and without open biomass burning as a case study in Singapore. The model results demonstrate that the soluble ON concentration in aerosols is episodically enriched during the fire events, compared to the without smoke simulations. However, the model results show that the daily soluble ON concentration can be also enhanced in the without smoke simulations during the same period, compared to the monthly averages. This indicates that care should be taken when using in-situ observations to constrain the soluble ON source strength from biomass burning. More accurate quantification of the soluble ON burdens with no smoke sources is therefore needed to assess the effect of biomass burning on bioavailable ON input to the oceans.

  8. Palladium catalyzed hydrogenation of bio-oils and organic compounds

    DOEpatents

    Elliott, Douglas C [Kennewick, WA; Hu, Jianli [Richland, WA; Hart,; Todd, R [Kennewick, WA; Neuenschwander, Gary G [Burbank, WA

    2011-06-07

    The invention provides palladium-catalyzed hydrogenations of bio-oils and certain organic compounds. Experimental results have shown unexpected and superior results for palladium-catalyzed hydrogenations of organic compounds typically found in bio-oils.

  9. Palladium catalyzed hydrogenation of bio-oils and organic compounds

    DOEpatents

    Elliott, Douglas C.; Hu, Jianli; Hart, Todd R.; Neuenschwander, Gary G.

    2008-09-16

    The invention provides palladium-catalyzed hydrogenations of bio-oils and certain organic compounds. Experimental results have shown unexpected and superior results for palladium-catalyzed hydrogenations of organic compounds typically found in bio-oils.

  10. A method of isolating organic compounds present in water

    NASA Technical Reports Server (NTRS)

    Calder, G. V.; Fritz, J.; Junk, G. A.

    1972-01-01

    Water sample is passed through a column containing macroreticular resin, which absorbs only nonionic organic compounds. These compounds are selectively separated using aqueous eluents of varying pH, or completely exuded with small amount of an organic eluent.

  11. Volatile Organic Compound Emissions from Humans Indoors.

    PubMed

    Tang, Xiaochen; Misztal, Pawel K; Nazaroff, William W; Goldstein, Allen H

    2016-12-06

    Research on the sources of indoor airborne chemicals has traditionally focused on outdoor air, building materials, furnishings, and activities such as smoking, cooking, and cleaning. Relatively little research has examined the direct role of occupant emissions, even though this source clearly contributes to indoor volatile organic compounds (VOCs) and influences indoor chemistry. In this work, we quantify occupant-related gaseous VOC emissions in a university classroom using a proton-transfer-reaction time-of-flight mass spectrometer. Time-resolved concentrations of VOCs in room air and supply air were measured continuously during occupied and unoccupied periods. The emission factor for each human-emitted VOC was determined by dividing the occupant-associated source rate by the corresponding occupancy. Among the most abundant species detected were compounds associated with personal care products. Also prominent were human metabolic emissions, such as isoprene, methanol, acetone, and acetic acid. Additional sources included human skin oil oxidation by ozone, producing compounds such as 4-oxopentanal (4-OPA) and 6-methyl-5-hepten-2-one (6-MHO). By mass, human-emitted VOCs were the dominant source (57%) during occupied periods in a well-ventilated classroom, with ventilation supply air the second most important (35%), and indoor nonoccupant emissions the least (8%). The total occupant-associated VOC emission factor was 6.3 mg h(-1) per person.

  12. Volatile Organic Compound Analysis in Istanbul

    NASA Astrophysics Data System (ADS)

    Ćapraz, Ö.; Deniz, A.; Öztürk, A.; Incecik, S.; Toros, H.; Coşkun, M.

    2012-04-01

    Volatile Organic Compound Analysis in Istanbul Ö. Çapraz1, A. Deniz1,3, A. Ozturk2, S. Incecik1, H. Toros1 and, M. Coskun1 (1) Istanbul Technical University, Faculty of Aeronautics and Astronautics, Department of Meteorology, 34469, Maslak, Istanbul, Turkey. (2) Istanbul Technical University, Faculty of Chemical and Metallurgical, Chemical Engineering, 34469, Maslak, Istanbul, Turkey. (3) Marmara Clean Air Center, Ministry of Environment and Urbanization, Nişantaşı, 34365, İstanbul, Turkey. One of the major problems of megacities is air pollution. Therefore, investigations of air quality are increasing and supported by many institutions in recent years. Air pollution in Istanbul contains many components that originate from a wide range of industrial, heating, motor vehicle, and natural emissions sources. VOC, originating mainly from automobile exhaust, secondhand smoke and building materials, are one of these compounds containing some thousands of chemicals. In spite of the risks to human health, relatively little is known about the levels of VOC in Istanbul. In this study, ambient air quality measurements of 32 VOCs including hydrocarbons, halogenated hydrocarbons and carbonyls were conducted in Kağıthane (Golden Horn) region in Istanbul during the winter season of 2011 in order to develop the necessary scientific framework for the subsequent developments. Kağıthane creek valley is the source part of the Golden Horn and one of the most polluted locations in Istanbul due to its topographical form and pollutant sources in the region. In this valley, horizontal and vertical atmospheric motions are very weak. The target compounds most commonly found were benzene, toluene, xylene and ethyl benzene. Concentrations of total hydrocarbons ranged between 1.0 and 10.0 parts per billion, by volume (ppbv). Ambient air levels of halogenated hydrocarbons appeared to exhibit unique spatial variations and no single factor seemed to explain trends for this group of

  13. Semivolatile organic compounds in indoor environments

    NASA Astrophysics Data System (ADS)

    Weschler, Charles J.; Nazaroff, William W.

    Semivolatile organic compounds (SVOCs) are ubiquitous in indoor environments, redistributing from their original sources to all indoor surfaces. Exposures resulting from their indoor presence contribute to detectable body burdens of diverse SVOCs, including pesticides, plasticizers, and flame retardants. This paper critically examines equilibrium partitioning of SVOCs among indoor compartments. It proceeds to evaluate kinetic constraints on sorptive partitioning to organic matter on fixed surfaces and airborne particles. Analyses indicate that equilibrium partitioning is achieved faster for particles than for typical indoor surfaces; indeed, for a strongly sorbing SVOC and a thick sorptive reservoir, equilibrium partitioning is never achieved. Mass-balance considerations are used to develop physical-science-based models that connect source- and sink-rates to airborne concentrations for commonly encountered situations, such as the application of a pesticide or the emission of a plasticizer or flame retardant from its host material. Calculations suggest that many SVOCs have long indoor persistence, even after the primary source is removed. If the only removal mechanism is ventilation, moderately sorbing compounds ( Koa > 10 10) may persist indoors for hundreds to thousands of hours, while strongly sorbing compounds ( Koa > 10 12) may persist for years. The paper concludes by applying the newly developed framework to explore exposure pathways of building occupants to indoor SVOCs. Accumulation of SVOCs as a consequence of direct air-to-human transport is shown to be potentially large, with a maximum indoor-air processing rate of 10-20 m 3/h for SVOC uptake by human skin, hair and clothing. Levels on human skin calculated with a simple model of direct air-to-skin transfer agree remarkably well with levels measured in dermal hand wipes for SVOCs possessing a wide range of octanol-air partition coefficients.

  14. Synthesis of Fuels and Value-Added Nitrogen-Containing Compounds from N2

    DTIC Science & Technology

    2014-11-24

    electron transfer steps throughout the cycle . The elucidation of synthetic routes to important intermediates in both nitrogen reduction and...AFRL-OSR-VA-TR-2014-0354 Synthesis of Fuels and Value-Added Nitrogen -Containing PAUL Chirik TRUSTEES OF PRINCETON UNIVERSITY Final Report 11/24/2014...v Prescribed by ANSI Std. Z39.18 Chirik – Final Report FA9550-11-1-0252 1 Synthesis of Fuels and Value-Added Nitrogen -Containing Compounds from

  15. SUPERCRITICAL FLUID EXTRACTION OF SEMI-VOLATILE ORGANIC COMPOUNDS FROM PARTICLES

    EPA Science Inventory

    A nitrogen oxide flux chamber was modified to measure the flux of semi-volatile organic compounds (SVOCs). Part of the modification involved the development of methods to extract SVOCs from polyurethane foam (PUF), sand, and soil. Breakthroughs and extraction efficiencies were ...

  16. Isotopic analyses of nitrogenous compounds from the Murchison meteorite: ammonia, amines, amino acids, and polar hydrocarbons

    NASA Technical Reports Server (NTRS)

    Pizzarello, S.; Feng, X.; Epstein, S.; Cronin, J. R.

    1994-01-01

    The combined volatile bases (ammonia, aliphatic amines, and possibly other bases), ammonia, amino acids, and polar hydrocarbons were prepared from the Murchison meteorite for isotopic analyses. The volatile bases were obtained by cryogenic transfer after acid-hydrolysis of a hot-water extract and analyzed by combined gas chromatography-mass spectrometry of pentafluoropropionyl derivatives. The aliphatic amines present in this preparation comprise a mixture that includes both primary and secondary isomers through C5 at a total concentration of > or = 100 nmoles g-1. As commonly observed for meteoritic organic compounds, almost all isomers through C5 are present, and the concentrations within homologous series decrease with increasing chain length. Ammonia was chromatographically separated from the other volatile bases and found at a concentration of 1.1-1.3 micromoles g-1 meteorite. The ammonia analyzed includes contributions from ammonium salts and the hydrolysis of extractable organic compounds, e.g., carboxamides. Stable isotope analyses showed the volatile bases to be substantially enriched in the heavier isotopes, relative to comparable terrestrial compounds delta D < or = +1221%; delta 13C = +22%; delta 15N = +93%). Ammonia, per se, was found to have a somewhat lower delta 15N value (+69%) than the total volatile bases; consequently, a higher delta 15N (>93%) can be inferred for the other bases, which include the amines. Solvent-extractable polar hydrocarbons obtained separately were found to be enriched in 15N (delta 15N = +104%). Total amino acids, prepared from a hydrolyzed hot-water extract by cation exchange chromatography, gave a delta 15N of +94%, a value in good agreement with that obtained previously. Nitrogen isotopic data are also given for amino acid fractions separated chromatographically. The delta 15N values of the Murchison soluble organic compounds analyzed to date fall within a rather narrow range (delta 15N = +94 +/- 8%), an observation

  17. Preparation of carbon nanoparticles and carbon nitride from high nitrogen compound

    DOEpatents

    Huynh, My Hang V.; Hiskey, Michael A.

    2009-09-01

    The high-nitrogen compound 3,6-di(azido)-1,2,4,5-tetrazine (DiAT) was synthesized by a relatively simple method and used as a precursor for the preparation of carbon nanospheres and nanopolygons, and nitrogen-rich carbon nitrides.

  18. Characterization of Organic Nitrogen in the Atmosphere Using High Resolution Aerosol Mass Spectrometry

    NASA Astrophysics Data System (ADS)

    Ge, X.; Sun, Y.; Chen, M.; Zhang, Q.

    2015-12-01

    Despite extensive efforts on characterizing organic nitrogen (ON) compounds in atmospheric aerosols and aqueous droplets, knowledge of ON chemistry is still limited, mainly due to its chemical complexity and lack of highly time-resolved measurements. This work is aimed at optimizing the method of using Aerodyne high-resolution time-of-flight aerosol mass spectrometer (HR-AMS) to characterize ON compounds in atmospheric aerosols. Seventy-five pure nitrogen-containing organic compounds covering a variety of functional groups were analyzed with the HR-AMS. Our results show that ON compounds commonly produce NHx+, NOx+, which are usually attributed to inorganic N species such as ammonium and nitrate, and CH2N+ at m/z = 28, which is rarely quantified in ambient aerosol due to large interference from N2+ in the air signal. As a result, using the nitrogen-to-carbon (N/C) calibration factor proposed by Aiken et al. (2008) on average leads to ~ 20% underestimation of N/C in ambient organic aerosol. A new calibration factor of 0.79 is proposed for determining the average N/C in organics. The relative ionization efficiencies (RIEs) of different ON species, on average, are found to be consistent with the default RIE value (1.4) for the total organics. The AMS mass spectral features of various types of ON species (amines, amides, amino acids, etc.) are examined and used for characterizing ON composition in ambient aerosols. Our results indicate that submicron organic aerosol measured during wintertime in Fresno, CA contains significant amounts of amino-compounds whereas more diversified ON species, including N-containing aromatic heterocycle (e.g., imidazoles), are observed in fog waters collected simultaneously. Our findings have important implications for understanding atmospheric ON behaviors via the widespread HR-AMS measurements of ambient aerosols and droplets.

  19. Identification and quantification of volatile organic compounds from a dairy

    NASA Astrophysics Data System (ADS)

    Filipy, Jenny; Rumburg, Brian; Mount, George; Westberg, Hal; Lamb, Brian

    Volatile organic compounds (VOCs) that contribute to odor and air quality problems have been identified from the Washington State University Knott Dairy Farm using gas chromatography-mass spectroscopy (GC-MS). Eighty-two VOCs were identified at a lactating cow open stall and 73 were detected from a slurry wastewater lagoon. These compounds included alcohols, aldehydes, ketones, esters, ethers, aromatic hydrocarbons, halogenated hydrocarbons, terpenes, other hydrocarbons, amines, other nitrogen containing compounds, and sulfur-containing compounds. The concentration of VOCs directly associated with cattle waste increased with ambient air temperature, with the highest concentrations present during the summer months. Concentrations of most detected compounds were below published odor detection thresholds. Emission rates of ethanol (1026±513 μg cow -1 s -1) and dimethyl sulfide (DMS) (13.8±10.3 μg cow -1 s -1) were measured from the lactating stall area using an atmospheric tracer method and concentrations were plotted using data over a 2-year period. Emission rates of acetone (3.03±0.85 ng cow -1 s -1), 2-butanone (145±35 ng cow -1 s -1), methyl isobutyl ketone (3.46±1.11 ng cow -1 s -1), 2-methyl-3-pentanone (25.1±8.0 ng cow -1 s -1), DMS (2.19±0.92 ng cow -1 s -1), and dimethyl disulfide (DMDS) (16.1±3.9 ng cow -1 s -1) were measured from the slurry waste lagoon using a laboratory emission chamber.

  20. Nitrogenous compounds stimulate glucose-derived acid production by oral Streptococcus and Actinomyces.

    PubMed

    Norimatsu, Yuka; Kawashima, Junko; Takano-Yamamoto, Teruko; Takahashi, Nobuhiro

    2015-09-01

    Both Streptococcus and Actinomyces can produce acids from dietary sugars and are frequently found in caries lesions. In the oral cavity, nitrogenous compounds, such as peptides and amino acids, are provided continuously by saliva and crevicular gingival fluid. Given that these bacteria can also utilize nitrogen compounds for their growth, it was hypothesized that nitrogenous compounds may influence their acid production; however, no previous studies have examined this topic. Therefore, the present study aimed to assess the effects of nitrogenous compounds (tryptone and glutamate) on glucose-derived acid production by Streptococcus and Actinomyces. Acid production was evaluated using a pH-stat method under anaerobic conditions, whereas the amounts of metabolic end-products were quantified using high performance liquid chromatography. Tryptone enhanced glucose-derived acid production by up to 2.68-fold, whereas glutamate enhanced Streptococcus species only. However, neither tryptone nor glutamate altered the end-product profiles, indicating that the nitrogenous compounds stimulate the whole metabolic pathways involving in acid production from glucose, but are not actively metabolized, nor do they alter metabolic pathways. These results suggest that nitrogenous compounds in the oral cavity promote acid production by Streptococcus and Actinomyces in vivo.

  1. Chemical characterization of dissolved organic compounds from coastal sea surface microlayers (Baltic Sea, Germany).

    PubMed

    van Pinxteren, Manuela; Müller, Conny; Iinuma, Yoshiteru; Stolle, Christian; Herrmann, Hartmut

    2012-10-02

    The physicochemical properties of the sea surface microlayer (SML), i.e. the boundary layer between the air and the sea, and its impact on air-sea exchange processes have been investigated for decades. However, a detailed description about these processes remains incomplete. In order to obtain a better chemical characterization of the SML, in a case study three pairs of SML and corresponding bulk water samples were taken in the southern Baltic Sea. The samples were analyzed for dissolved organic carbon and dissolved total nitrogen, as well as for several organic nitrogen containing compounds and carbohydrates, namely aliphatic amines, dissolved free amino acids, dissolved free monosaccharides, sugar alcohols, and monosaccharide anhydrates. Therefore, reasonable analytical procedures with respect to desalting and enrichment were established. All aliphatic amines and the majority of the investigated amino acids (11 out of 18) were found in the samples with average concentrations between 53 ng L(-1) and 1574 ng L(-1). The concentrations of carbohydrates were slightly higher, averaging 2900 ng L(-1). Calculation of the enrichment factor (EF) between the sea surface microlayer and the bulk water showed that dissolved total nitrogen was more enriched (EF: 1.1 and 1.2) in the SML than dissolved organic carbon (EF: 1.0 and 1.1). The nitrogen containing organic compounds were generally found to be enriched in the SML (EF: 1.9-9.2), whereas dissolved carbohydrates were not enriched or even depleted (EF: 0.7-1.2). Although the investigated compounds contributed on average only 0.3% to the dissolved organic carbon and 0.4% to the total dissolved nitrogen fraction, these results underline the importance of single compound analysis to determine SML structure, function, and its potential for a transfer of compounds into the atmosphere.

  2. IRRADIATION METHOD OF CONVERTING ORGANIC COMPOUNDS

    DOEpatents

    Allen, A.O.; Caffrey, J.M. Jr.

    1960-10-11

    A method is given for changing the distribution of organic compounds from that produced by the irradiation of bulk alkane hydrocarbons. This method consists of depositing an alkane hydrocarbon on the surface of a substrate material and irradiating with gamma radiation at a dose rate of more than 100,000 rads. The substrate material may be a metal, metal salts, metal oxides, or carbons having a surface area in excess of 1 m/sup 2//g. The hydrocarbons are deposited in layers of from 0.1 to 10 monolayers on the surfaces of these substrates and irradiated. The product yields are found to vary from those which result from the irradiation of bulk hydrocarbons in that there is an increase in the quantity of branched hydrocarbons.

  3. Volatilization of organic compounds from streams

    USGS Publications Warehouse

    Rathburn, R.E.; Tai, D.Y.

    1982-01-01

    Mass-transfer coefficients for the volatilization of ethylene and propane were correlated with the hydraulic and geometric properties of seven streams, and predictive equations were developed. The equations were evaluated using a normalized root-mean-square error as the criterion of comparison. The two best equations were a two-variable equation containing the energy dissipated per unit mass per unit time and the average depth of flow and a three-variable equation containing the average velocity, the average depth of flow, and the slope of the stream. Procedures for adjusting the ethylene and propane coefficients for other organic compounds were evaluated. These procedures are based on molecular diffusivity, molecular diameter, or molecular weight. Because of limited data, none of these procedures have been extensively verified. Therefore, until additional data become available, it is suggested that the mass-transfer coefficient be assumed to be inversely proportional to the square root of the molecular weight.

  4. Extraction of organic compounds from solid samples

    SciTech Connect

    Junk, G.A.; Richard, J.J.

    1986-04-01

    Pyridine, benzene, cyclohexane, methylene chloride, dimethyl sulfoxide, dimethylformamide, and n-methylpyrrolidone have been compared for the extraction of polycyclic organic materials (POMs) from urban air, diesel, and stack particulate samples. Both sonic and Soxhlet techniques have been examined for both natural environmental particulates and particulates spiked with selected POMs. The extraction results vary for different polycyclic compounds adsorbed on different solid matrices, so no single solvent or extraction technique could be unambiguously recommended. However, comparative average results for 14 compounds spiked onto fly ash at 0.1, 0.25, and 1.0 ..mu..g/g showed pyridine to have 1.5 times more extraction efficiency than benzene. These and other reported results suggest that pyridine deserves more attention as an extractant for particulate samples. In separate tests, recoveries of POMs from fly ash were not improved by deactivation with aqueous solutions of ammonium hydroxide, thiocyanate and carbonate, and sodium nitrite prior to the extraction. 39 references, 5 tables.

  5. The contribution of dissolved organic nitrogen and chloramines to nitrogenous disinfection byproduct formation from natural organic matter.

    PubMed

    Chuang, Yi-Hsueh; Lin, Angela Yu-Chen; Wang, Xiao-huan; Tung, Hsin-hsin

    2013-03-01

    The direct incorporation of chloramines and dissolved organic nitrogen (DON) may provide the nitrogen for nitrogenous disinfection byproducts (N-DBPs). This study explores the contributions of natural DON and chloramine incorporation to the formation of N-DBPs during chloramination. This study also evaluates the relationship between N-DBPs and carbonaceous DBPs by investigating four sources of dissolved organic matter with different DON-to-dissolved organic carbon (DOC) ratios. During chloramination, dihaloacetonitrile (DXAN) formation is correlated with the summation of trihalomethanes (THMs) and dichloroacetic acids (DXAAs) yield in molar basis at pH > 6. This study tests the formation kinetics of THMs, DXAAs, and DXANs during chloramination, explores the changes in DBP formation potential before and after a sequence of ozonation and chloramination, and tracks the nitrogen source of dichloroacetonitrile. The results support the hypothesis that THMs, DXAAs, and DXANs mainly derive from similar precursors upon chloramination. In addition, the precursor of HANs was approximately 10% (on a molar basis) of that of THMs and HAAs combined. The N-nitrosodimethylamine (NDMA) formation potential is correlated with DON/DOC in hydrophilic and transphilic fractions. Isotope (15)N-labeled monochloramine coupled with LC-electrospray ionization-tandem mass spectrometry was used to explore the nitrogen source of NDMA formed in chloraminated organic fractions. The results indicate that the nitroso group of the formed NDMA originates mainly from chloramines.

  6. Tropospheric volatile organic compounds in China.

    PubMed

    Guo, H; Ling, Z H; Cheng, H R; Simpson, I J; Lyu, X P; Wang, X M; Shao, M; Lu, H X; Ayoko, G; Zhang, Y L; Saunders, S M; Lam, S H M; Wang, J L; Blake, D R

    2017-01-01

    Photochemical smog, characterized by high concentrations of ozone (O3) and fine particles (PM2.5) in the atmosphere, has become one of the top environmental concerns in China. Volatile organic compounds (VOCs), one of the key precursors of O3 and secondary organic aerosol (SOA) (an important component of PM2.5), have a critical influence on atmospheric chemistry and subsequently affect regional and global climate. Thus, VOCs have been extensively studied in many cities and regions in China, especially in the North China Plain, the Yangtze River Delta and the Pearl River Delta regions where photochemical smog pollution has become increasingly worse over recent decades. This paper reviews the main studies conducted in China on the characteristics and sources of VOCs, their relationship with O3 and SOA, and their removal technology. This paper also provides an integrated literature review on the formulation and implementation of effective control strategies of VOCs and photochemical smog, as well as suggestions for future directions of VOCs study in China.

  7. Organic compounds in meteorites and their origins

    NASA Technical Reports Server (NTRS)

    Hayatsu, R.; Anders, E.

    1981-01-01

    The current investigation represents an extensively updated version of a review conducted by Anders et al. (1973). The investigation takes into account the literature through mid-1980. It is pointed out that Type 1 carbonaceous chondrites (C1) contain 6% of their cosmic complement of carbon, mainly in the form of organic matter. Most authors now agree that this material represents primitive prebiotic matter. The principal questions remaining are what abiotic processes formed the organic matter, and to what extent these processes took place in locales other than the solar nebula, such as interstellar clouds or meteorite parent bodes. The problem is approached in three stages. It is attempted to reconstruct the physical conditions during condensation from the clues contained in the inorganic matrix of the meteorite. The condensation behavior of carbon under these conditions is determined on the basis of thermodynamic calculations. Model experiments on the condensation of carbon are performed, and the synthesized compounds are compared with those actually found in meteorites.

  8. Tritium labeling of organic compounds deposited on porous structures

    DOEpatents

    Ehrenkaufer, Richard L. E.; Wolf, Alfred P.; Hembree, Wylie C.

    1979-01-01

    An improved process for labeling organic compounds with tritium is carried out by depositing the selected compound on the extensive surface of a porous structure such as a membrane filter and exposing the membrane containing the compound to tritium gas activated by the microwave discharge technique. The labeled compound is then recovered from the porous structure.

  9. Nuclear Magnetic Resonance Signatures of Nitrogen-Containing Compounds

    DTIC Science & Technology

    1989-08-01

    FID) trinitrotoluene (TNT) hexamethylenetetramine (HMT) pentaerythrifol tetranitrate (PETN) mannitol AB 6STRACT (Co.a , nmw~eem~wmy a~x1 n4Wy ,bdk...effects in one or more explosive simulant compounds, including hexamethylenetetramine . Task 3. Investigate Explosive Compounds. Investigate hydrogen...pumping of weakly-allowed transitions in hexamethylenetetramine , an explosive simulant, is presented in Appendix A. The theoretical framework for the

  10. The import and export of organic nitrogen species at a Scottish ombrotrophic peatland

    NASA Astrophysics Data System (ADS)

    McKenzie, Rebecca M.; Özel, Mustafa Z.; Cape, J. Neil; Drewer, Julia; Dinsmore, Kerry J.; Nemitz, Eiko; Sim Tang, Y.; van Dijk, Netty; Anderson, Margaret; Hamilton, Jacqueline F.; Sutton, Mark A.; Gallagher, Martin W.; Skiba, Ute

    2016-04-01

    Dissolved organic nitrogen (DON) contributes significantly to the overall nitrogen budget, but is not routinely measured in precipitation or stream water. In order to investigate the contribution of DON to the deposition and export of N, precipitation, stream and soil water samples were collected from an ombrotrophic peatland and analysed for DON over a 2-year period. In wet-only deposition DON contributed up to 10 % of the total dissolved nitrogen (TDN) and was the most dominant fraction in soil water (99 %) and stream water (75 %). NH4+ was the most dominate form of N in precipitation, with NO3- contributing the least to precipitation, soil water and stream water. Precipitation and stream DON were qualitatively analysed by a two-dimensional gas chromatograph coupled to a nitrogen chemiluminescence detector (GC × GC-NCD) after trapping onto C18 solid phase extraction (SPE) cartridges. Ten unique compounds were detected and five identified as pyrrole, benzonitrile, dodecylamine, N-nitrosodipropylamine and decylamine. Five compounds were present in both precipitation and stream samples: pyrrole, benzonitrile and three unidentified compounds. The SPE-extraction efficiency for DON was very low (11 %), but with improvements DON speciation could become a valuable tool to provide information on its sources and pathways and inform chemical transport models.

  11. Improvements to the characterization of organic nitrogen chemistry and deposition in CMAQ

    EPA Science Inventory

    Excess atmospheric nitrogen deposition can cause significant harmful effects to ecosystems. Organic nitrogen deposition can be an important contributor to the total nitrogen budget, contributing 10-30%, however there are large uncertainties in the chemistry and deposition of thes...

  12. Improvements to the characterization of organic nitrogen chemistry and deposition in CMAQ (CMAS Presentation)

    EPA Science Inventory

    Excess atmospheric nitrogen deposition can cause significant harmful effects to ecosystems. Organic nitrogen deposition can be an important contributor to the total nitrogen budget, contributing 10-30%, however there are large uncertainties in the chemistry and deposition of thes...

  13. Improvements to the treatment of organic nitrogen chemistry & deposition in CMAQ

    EPA Science Inventory

    Excess atmospheric nitrogen deposition can cause significant harmful effects to ecosystems. Organic nitrogen deposition can be an important contributor to the total nitrogen budget, contributing 10-30%, however there are large uncertainties in the chemistry and deposition of thes...

  14. Soil biochemical properties of grassland ecosystems under anthropogenic emission of nitrogen compounds

    NASA Astrophysics Data System (ADS)

    Kudrevatykh, Irina; Ivashchenko, Kristina; Ananyeva, Nadezhda

    2016-04-01

    Inflow of pollutants in terrestrial ecosystems nowadays increases dramatically, that might be led to disturbance of natural biogeochemical cycles and landscapes structure. Production of nitrogen fertilizers is one of the air pollution sources, namely by nitrogen compounds (NH4+, NO3-, NO2-). Air pollution by nitrogen compounds of terrestrial ecosystems might be affected on soil biochemical properties, which results increasing mineral nitrogen content in soil, changing soil P/N and Al/Ca ratios, and, finally, the deterioration of soil microbial community functioning. The research is focused on the assessment of anthropogenic emission of nitrogen compounds on soil properties of grassland ecosystems in European Russia. Soil samples (Voronic Chernozem Pachic, upper 10 cm mineral layer, totally 10) were taken from grassland ecosystem: near (5-10 m) nitrogen fertilizer factory (NFF), and far from it (20-30 km, served as a control) in Tula region. In soil samples the NH4+ and NO3- (Kudeyarov's photocolorimetric method), P, Ca, Al (X-ray fluorescence method) contents were measured. Soil microbial biomass carbon (Cmic) was analyzed by substrate-induced respiration method. Soil microbial respiration (MR) was assessed by CO2 rate production. Soil microbial metabolic quotient (qCO2) was calculated as MR/Cmic ratio. Near NFF the soil ammonium and nitrate nitrogen contents were a strongly varied, variation coefficient (CV) was 42 and 86This study was supported by Russian Foundation of Basic Research Grant No. 14-04-00098, 15-44-03220, 15-04-00915.

  15. Formation of Haloacetonitriles, Haloacetamides, and Nitrogenous Heterocyclic Byproducts by Chloramination of Phenolic Compounds.

    PubMed

    Nihemaiti, Maolida; Le Roux, Julien; Hoppe-Jones, Christiane; Reckhow, David A; Croué, Jean-Philippe

    2017-01-03

    The potential formation of nitrogenous disinfection byproducts (N-DBPs) was investigated from the chloramination of nitrogenous and non-nitrogenous aromatic compounds. All molecules led to the formation of known N-DBPs (e.g., dichloroacetonitrile, dichloroacetamide) with various production yields. Resorcinol, a major precursor of chloroform, also formed di/trichloroacetonitrile, di/trichloroacetamide, and haloacetic acids, indicating that it is a precursor of both N-DBPs and carbonaceous DBPs (C-DBPs) upon chloramination. More detailed experiments were conducted on resorcinol to understand N-DBPs formation mechanisms and to identify reaction intermediates. Based on the accurate mass from high resolution Quadrupole Time-of-Flight GC-MS (GC-QTOF) and fragmentation patterns from electronic impact and positive chemical ionization modes, several products were tentatively identified as nitrogenous heterocyclic compounds (e.g., 3-chloro-5-hydroxy-1H-pyrrole-2-one with dichloromethyl group, 3-chloro-2,5-pyrroledione). These products were structurally similar to the heterocyclic compounds formed during chlorination, such as the highly mutagenic MX (3-chloro-4-(dichloromethyl)-5-hydroxy-2(5H)-furanone) or halogenated pyrroles. To our knowledge, this is the first time that the formation of halogenated nitrogenous heterocyclic compounds is reported from chloramination process. The formation of these nitrogenous byproducts during chloramination might be of concern considering their potential toxicity.

  16. BASIC CHEMICAL RESEARCH PROGRAM. ELECTRICAL PROPERTIES OF ORGANIC COMPOUNDS

    DTIC Science & Technology

    BENZENE, *CYANIDES, *HYDROXIDES, *ORGANIC COMPOUNDS, ACETYLENES, ALKYL RADICALS, AMIDES, ANILINES , BENZALDEHYDES, CHEMICAL REACTIONS , CONDENSATION... REACTIONS , ELECTRICAL CONDUCTIVITY, MATERIALS, MEASUREMENT, MONOCYCLIC COMPOUNDS, PHENOLS, PHENYL RADICALS, QUINONES, SOLID STATE PHYSICS, SYNTHESIS.

  17. Breath measurements as volatile organic compound biomarkers.

    PubMed Central

    Wallace, L; Buckley, T; Pellizzari, E; Gordon, S

    1996-01-01

    A brief review of the uses of breath analysis in studies of environmental exposure to volatile organic compounds (VOCs) is provided. The U.S. Environmental Protection Agency's large-scale Total Exposure Assessment Methodology Studies have measured concentrations of 32 target VOCs in the exhaled breath of about 800 residents of various U.S. cities. Since the previous 12-hr integrated personal air exposures to the same chemicals were also measured, the relation between exposure and body burden is illuminated. Another major use of the breath measurements has been to detect unmeasured pathways of exposure; the major impact of active smoking on exposure to benzene and styrene was detected in this way. Following the earlier field studies, a series of chamber studies have provided estimates of several important physiological parameters. Among these are the fraction, f, of the inhaled chemical that is exhaled under steady-state conditions and the residence times. tau i in several body compartments, which may be associated with the blood (or liver), organs, muscle, and fat. Most of the targeted VOCs appear to have similar residence times of a few minutes, 30 min, several hours, and several days in the respective tissue groups. Knowledge of these parameters can be helpful in estimating body burden from exposure or vice versa and in planning environmental studies, particularly in setting times to monitor breath in studies of the variation with time of body burden. Improvements in breath methods have made it possible to study short-term peak exposure situations such as filling a gas tank or taking a shower in contaminated water. PMID:8933027

  18. Breath measurements as volatile organic compound biomarkers.

    PubMed

    Wallace, L; Buckley, T; Pellizzari, E; Gordon, S

    1996-10-01

    A brief review of the uses of breath analysis in studies of environmental exposure to volatile organic compounds (VOCs) is provided. The U.S. Environmental Protection Agency's large-scale Total Exposure Assessment Methodology Studies have measured concentrations of 32 target VOCs in the exhaled breath of about 800 residents of various U.S. cities. Since the previous 12-hr integrated personal air exposures to the same chemicals were also measured, the relation between exposure and body burden is illuminated. Another major use of the breath measurements has been to detect unmeasured pathways of exposure; the major impact of active smoking on exposure to benzene and styrene was detected in this way. Following the earlier field studies, a series of chamber studies have provided estimates of several important physiological parameters. Among these are the fraction, f, of the inhaled chemical that is exhaled under steady-state conditions and the residence times. tau i in several body compartments, which may be associated with the blood (or liver), organs, muscle, and fat. Most of the targeted VOCs appear to have similar residence times of a few minutes, 30 min, several hours, and several days in the respective tissue groups. Knowledge of these parameters can be helpful in estimating body burden from exposure or vice versa and in planning environmental studies, particularly in setting times to monitor breath in studies of the variation with time of body burden. Improvements in breath methods have made it possible to study short-term peak exposure situations such as filling a gas tank or taking a shower in contaminated water.

  19. Volatile organic compound remedial action project

    SciTech Connect

    1991-12-01

    This Environmental Assessment (EA) reviews a proposed project that is planned to reduce the levels of volatile organic compound (VOC) contaminants present in the Mound domestic water supply. The potable and industrial process water supply for Mound is presently obtained from a shallow aquifer via on-site production wells. The present levels of VOCs in the water supply drawn from the on-site wells are below the maximum contaminant levels (MCLs) permissible for drinking water under Safe Drinking Water Act (SDWA; 40 CFR 141); however, Mound has determined that remedial measures should be taken to further reduce the VOC levels. The proposed project action is the reduction of the VOC levels in the water supply using packed tower aeration (PTA). This document is intended to satisfy the requirements of the National Environmental Policy Act (NEPA) of 1969 and associated Council on Environmental Quality regulations (40 CFR parts 1500 through 1508) as implemented through U.S. Department of Energy (DOE) Order 5440.1D and supporting DOE NEPA Guidelines (52 FR 47662), as amended (54 FR 12474; 55 FR 37174), and as modified by the Secretary of Energy Notice (SEN) 15-90 and associated guidance. As required, this EA provides sufficient information on the probable environmental impacts of the proposed action and alternatives to support a DOE decision either to prepare an Environmental Impact Statement (EIS) or issue a Finding of No Significant Impact (FONSI).

  20. Organic compounds in concrete from demolition works.

    PubMed

    Van Praagh, M; Modin, H; Trygg, J

    2015-11-01

    This study aims to verify the effect of physically removing the outer surface of contaminated concrete on total contents and on potential mobility of pollutants by means of leaching tests. Reclaimed concrete from 3 industrial sites in Sweden were included: A tar impregnated military storage, a military tar track-depot, as well as concrete constructions used for disposing of pesticide production surplus and residues. Solid materials and leachates from batch and column leaching tests were analysed for metals, Cl, F, SO4, DOC and contents of suspected organic compounds (polycyclic aromatic hydrocarbons, PAH, and pesticides/substances for pesticide production such as phenoxy acids, chlorophenols and chlorocresols, respectively). In case of PAH contaminated concrete, results indicate that removing 1 or 5 mm of the surface lead to total concentrations below the Swedish guidelines for recycling of aggregates and soil in groundwork constructions. 3 out of 4 concrete samples contaminated with pesticides fulfilled Swedish guidelines for contaminated soil. Results from batch and column leaching tests indicated, however, that concentrations above environmental quality standards for certain PAH and phenoxy acids, respectively, might occur at site when the crushed concrete is recycled in groundwork constructions. As leaching tests engaged in the study deviated from leaching test standards with a limited number of samples, the potential impact of the leaching tests' equipment on measured PAH and pesticide leachate concentrations has to be evaluated in future work.

  1. Volatile Organic Compound Emissions by Agricultural Crops

    NASA Astrophysics Data System (ADS)

    Ormeno, E.; Farres, S.; Gentner, D.; Park, J.; McKay, M.; Karlik, J.; Goldstein, A.

    2008-12-01

    Biogenic Volatile Organic Compounds (BVOCs) participate in ozone and aerosol formation, and comprise a substantial fraction of reactive VOC emission inventories. In the agriculturally intensive Central Valley of California, emissions from crops may substantially influence regional air quality, but emission potentials have not been extensively studied with advanced instrumentation for many important crops. Because crop emissions may vary according to the species, and California emission inventories are constructed via a bottom-up approach, a better knowledge of the emission rate at the species-specific level is critical for reducing uncertainties in emission inventories and evaluating emission model performance. In the present study we identified and quantified the BVOCs released by dominant agricultural crops in California. A screening study to investigate both volatile and semivolatile BVOC fractions (oxygenated VOCs, isoprene, monoterepenes, sesquiterpenes, etc.) was performed for 25 crop species (at least 3 replicates plants each), including branch enclosures of woody species (e.g. peach, mandarin, grape, pistachio) and whole plant enclosures for herbaceous species (e.g. onion, alfalfa, carrot), through a dynamic cuvette system with detection by PTRMS, in-situ GCMS/FID, and collection on carbon-based adsorbents followed by extraction and GCMS analysis. Emission data obtained in this study will allow inclusion of these crops in BVOC emission inventories and air quality simulations.

  2. Soil amino compound and carbohydrate contents influenced by organic amendments

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Amino compounds (i. e. amino acids and sugars), and carbohydrates are labile organic components and contribute to the improvement of soil fertility and quality. Animal manure and other organic soil amendments are rich in both amino compounds and carbohydrates, hence organic soil amendments might af...

  3. The carbon bonus of organic nitrogen enhances nitrogen use efficiency of plants

    PubMed Central

    Cambui, Camila Aguetoni; Gruffman, Linda; Palmroth, Sari; Oren, Ram; Näsholm, Torgny

    2016-01-01

    Abstract The importance of organic nitrogen (N) for plant nutrition and productivity is increasingly being recognized. Here we show that it is not only the availability in the soil that matters, but also the effects on plant growth. The chemical form of N taken up, whether inorganic (such as nitrate) or organic (such as amino acids), may significantly influence plant shoot and root growth, and nitrogen use efficiency (NUE). We analysed these effects by synthesizing results from multiple laboratory experiments on small seedlings (Arabidopsis, poplar, pine and spruce) based on a tractable plant growth model. A key point is that the carbon cost of assimilating organic N into proteins is lower than that of inorganic N, mainly because of its carbon content. This carbon bonus makes it more beneficial for plants to take up organic than inorganic N, even when its availability to the roots is much lower – up to 70% lower for Arabidopsis seedlings. At equal growth rate, root:shoot ratio was up to three times higher and nitrogen productivity up to 20% higher for organic than inorganic N, which both are factors that may contribute to higher NUE in crop production. PMID:27241731

  4. Nitrogen addition influences formation of aroma compounds, volatile acidity and ethanol in nitrogen deficient media fermented by Saccharomyces cerevisiae wine strains.

    PubMed

    Barbosa, Catarina; Falco, Virgilio; Mendes-Faia, Arlete; Mendes-Ferreira, Ana

    2009-08-01

    The effects of nitrogen addition into nitrogen deficient/depleted media on the release of aroma compounds post-fermentation were investigated in three commercial yeast strains of Saccharomyces cerevisiae which highlight the yeast strain effect as well as nitrogen effects. By comparing the two timings of nitrogen addition, prior to fermentation or later at stationary phase (72 h), it was shown that nitrogen addition at stationary phase significantly decreases ethanol and acetic acid formation and significantly increases the following compounds: 2-phenylethanol, ethyl isobutyrate, 2-phenylethyl acetate, ethyl 2-methylbutyrate and ethyl propionate in the three strains, and also isovaleric acid, isoamyl alcohol and ethyl isovalerate in both PYCC4072 and UCD522. The strain EC1118 produced significantly less medium chain fatty acids, hexanoic, octanoic and decanoic acids and their respective esters after nitrogen addition. Therefore, timing of nitrogen addition to a ferment media can vary the concentration of certain aroma compound and might provide a means for varying wine composition.

  5. Method and reaction pathway for selectively oxidizing organic compounds

    DOEpatents

    Camaioni, Donald M.; Lilga, Michael A.

    1998-01-01

    A method of selectively oxidizing an organic compound in a single vessel comprises: a) combining an organic compound, an acid solution in which the organic compound is soluble, a compound containing two oxygen atoms bonded to one another, and a metal ion reducing agent capable of reducing one of such oxygen atoms, and thereby forming a mixture; b) reducing the compound containing the two oxygen atoms by reducing one of such oxygen atoms with the metal ion reducing agent to, 1) oxidize the metal ion reducing agent to a higher valence state, and 2) produce an oxygen containing intermediate capable of oxidizing the organic compound; c) reacting the oxygen containing intermediate with the organic compound to oxidize the organic compound into an oxidized organic intermediate, the oxidized organic intermediate having an oxidized carbon atom; d) reacting the oxidized organic intermediate with the acid counter ion and higher valence state metal ion to bond the acid counter ion to the oxidized carbon atom and thereby produce a quantity of an ester incorporating the organic intermediate and acid counter ion; and e) reacting the oxidized organic intermediate with the higher valence state metal ion and water to produce a quantity of alcohol which is less than the quantity of ester, the acid counter ion incorporated in the ester rendering the carbon atom bonded to the counter ion less reactive with the oxygen containing intermediate in the mixture than is the alcohol with the oxygen containing intermediate.

  6. Oceanic protection of prebiotic organic compounds from UV radiation

    NASA Technical Reports Server (NTRS)

    Cleaves, H. J.; Miller, S. L.; Bada, J. L. (Principal Investigator)

    1998-01-01

    It is frequently stated that UV light would cause massive destruction of prebiotic organic compounds because of the absence of an ozone layer. The elevated UV flux of the early sun compounds this problem. This applies to organic compounds of both terrestrial and extraterrestrial origin. Attempts to deal with this problem generally involve atmospheric absorbers. We show here that prebiotic organic polymers as well as several inorganic compounds are sufficient to protect oceanic organic molecules from UV degradation. This aqueous protection is in addition to any atmospheric UV absorbers and should be a ubiquitous planetary phenomenon serving to increase the size of planetary habitable zones.

  7. A PARAMETRIC STUDY OF THIN FILMS OF TANTALUM-NITROGEN COMPOUNDS.

    DTIC Science & Technology

    Thin films of tantalum-nitrogen compounds were deposited by reactive sputtering onto quartz substrates for electrical and optical measurements and onto carbon-coated grids for electron diffraction analysis using hot- and cold-stage techniques. The films were deposited at substrate temperatures varying from room temperature to 500C at sputtering voltages varying from 1 to 5 kV. The relationship between nitrogen content and lattice structure is presented and compared with resistivity and optical absorption measurements. (Author)

  8. Volatile compounds formation in alcoholic fermentation from grapes collected at 2 maturation stages: influence of nitrogen compounds and grape variety.

    PubMed

    Martínez-Gil, Ana M; Garde-Cerdán, Teresa; Lorenzo, Cándida; Lara, José Félix; Pardo, Francisco; Salinas, M Rosario

    2012-01-01

    The aim of this work was to study the influence of nitrogen compounds on the formation of volatile compounds during the alcoholic fermentation carried out with 4 nonaromatic grape varieties collected at 2 different maturation stages. To do this, Monastrell, Merlot, Syrah, and Petit Verdot grapes were collected 1 wk before harvest and at harvest. Then, the musts were inoculated with the same Saccharomyces cerevisiae yeast strain and were fermented in the same winemaking conditions. Amino acids that showed the highest and the lowest concentration in the must were the same, regardless of the grape variety and maturation stage. Moreover, the consumption of amino acids during the fermentation increased with their concentration in the must. The formation of volatile compounds was not nitrogen composition dependent. However, the concentration of amino acids in the must from grapes collected 1 wk before harvest can be used as a parameter to estimate the concentration of esters in wines from grapes collected at harvest and therefore to have more information to know the grape oenological capacity. Application of principal components analysis (PCA) confirmed the possibility to estimate the concentration of esters in the wines with the concentration of nitrogen compounds in the must.

  9. Effect of ambient temperature on losses of volatile nitrogen compounds from stored laying hen manure.

    PubMed

    Pratt, E V; Rose, S P; Keeling, A A

    2002-09-01

    Eight one tonne lots of laying hen manure were stored in individual, environmentally controlled chambers for 18-weeks at one of four constant temperatures: 12, 15, 20 and 25 degrees C. The losses of volatile nitrogen compounds, ammonia, and changes in dry matter and pH were measured during the storage period. There was a linear (P < 0.001) loss of nitrogen from the manure over the 18-week storage period. This loss represented approximately 60% of the initial nitrogen present in the manure. The rate of nitrogen loss increased non-linearly (P < 0.05) with increasing storage temperature. Poultry housing systems that provide low temperature storage of manure are recommended to reduce the volatile nitrogen losses from egg-laying enterprises.

  10. Nitrated Secondary Organic Tracer Compounds in Biomass Burning Smoke

    NASA Astrophysics Data System (ADS)

    Iinuma, Y.; Böge, O.; Gräfe, R.; Herrmann, H.

    2010-12-01

    Natural and human-initiated biomass burning releases large amounts of gases and particles into the atmosphere, impacting climate, environment and affecting public health. Several hundreds of compounds are emitted from biomass burning and these compounds largely originate from the pyrolysis of biopolymers such as lignin, cellulose and hemicellulose. Some of compounds are known to be specific to biomass burning and widely recognized as tracer compounds that can be used to identify the presence of biomass burning PM. Detailed chemical analysis of biomass burning influenced PM samples often reveals the presence compounds that correlated well with levoglucosan, a known biomass burning tracer compound. In particular, nitrated aromatic compounds correlated very well with levoglucosan, indicating that biomass burning as a source for this class of compounds. In the present study, we present evidence for the presence of biomass burning originating secondary organic aerosol (BSOA) compounds in biomass burning influenced ambient PM. These BSOA compounds are typically nitrated aromatic compounds that are produced in the oxidation of precursor compounds in the presence of NOx. The precursor identification was performed from a series of aerosol chamber experiments. m-Cresol, which is emitted from biomass burning at significant levels, is found to be a major precursor compounds for nitrated BSOA compounds found in the ambient PM. We estimate that the total concentrations of these compounds in the ambient PM are comparable to biogenic SOA compounds in winter months, indicating the BSOA contributes important amounts to the regional organic aerosol loading.

  11. On-line Analysis of Nitrogen Containing Compounds in Complex Hydrocarbon Matrixes.

    PubMed

    Ristic, Nenad D; Djokic, Marko R; Van Geem, Kevin M; Marin, Guy B

    2016-08-05

    The shift to heavy crude oils and the use of alternative fossil resources such as shale oil are a challenge for the petrochemical industry. The composition of heavy crude oils and shale oils varies substantially depending on the origin of the mixture. In particular they contain an increased amount of nitrogen containing compounds compared to the conventionally used sweet crude oils. As nitrogen compounds have an influence on the operation of thermal processes occurring in coker units and steam crackers, and as some species are considered as environmentally hazardous, a detailed analysis of the reactions involving nitrogen containing compounds under pyrolysis conditions provides valuable information. Therefore a novel method has been developed and validated with a feedstock containing a high nitrogen content, i.e., a shale oil. First, the feed was characterized offline by comprehensive two-dimensional gas chromatography (GC × GC) coupled with a nitrogen chemiluminescence detector (NCD). In a second step the on-line analysis method was developed and tested on a steam cracking pilot plant by feeding pyridine dissolved in heptane. The former being a representative compound for one of the most abundant classes of compounds present in shale oil. The composition of the reactor effluent was determined via an in-house developed automated sampling system followed by immediate injection of the sample on a GC × GC coupled with a time-of-flight mass spectrometer (TOF-MS), flame ionization detector (FID) and NCD. A novel method for quantitative analysis of nitrogen containing compounds using NCD and 2-chloropyridine as an internal standard has been developed and demonstrated.

  12. Novel lithium-nitrogen compounds at ambient and high pressures

    PubMed Central

    Shen, Yanqing; Oganov, Artem R.; Qian, Guangri; Zhang, Jin; Dong, Huafeng; Zhu, Qiang; Zhou, Zhongxiang

    2015-01-01

    Using ab initio evolutionary simulations, we predict the existence of five novel stable Li-N compounds at pressures from 0 to 100 GPa (Li13N, Li5N, Li3N2, LiN2, and LiN5). Structures of these compounds contain isolated N atoms, N2 dimers, polyacetylene-like N chains and N5 rings, respectively. The structure of Li13N consists of Li atoms and Li12N icosahedra (with N atom in the center of the Li12 icosahedron) – such icosahedra are not described by Wade-Jemmis electron counting rules and are unique. Electronic structure of Li-N compounds is found to dramatically depend on composition and pressure, making this system ideal for studying metal-insulator transitions. For example, the sequence of lowest-enthalpy structures of LiN3 shows peculiar electronic structure changes with increasing pressure: metal-insulator-metal-insulator. This work also resolves the previous controversies of theory and experiment on Li2N2. PMID:26374272

  13. [Organisms producing hypolipidemic compounds with antioxidant activity].

    PubMed

    Puzhevskaia, T O; Grammatikova, N E; Bibikova, M V; Katlinskiĭ, A V

    2009-01-01

    Complex compounds produced by fungal cultures of Lecanicilium and Beauveria with both high hypolipidemic and antioxydant activities were screened. Two fractions of the hypolipipidemic compounds with antioxidant activity of 95 and 75% in a dose of 25 mcg/ml were isolated.

  14. Relative Stabilities of Organic Compounds Using Benson's Additivity Rules.

    ERIC Educational Resources Information Center

    Vitale, Dale E.

    1986-01-01

    Shows how the structure-energy principle can be presented in organic chemistry (without having to resort to quantum mechanics) by use of Benson's Additive Rules. Examples of the application to several major classes of organic compounds are given.

  15. A sensitive search for organics (CH4, CH3OH, H2CO, C2H6, C2H2, C2H4), hydroperoxyl (HO2), nitrogen compounds (N2O, NH3, HCN) and chlorine species (HCl, CH3Cl) on Mars using ground-based high-resolution infrared spectroscopy

    NASA Astrophysics Data System (ADS)

    Villanueva, G. L.; Mumma, M. J.; Novak, R. E.; Radeva, Y. L.; Käufl, H. U.; Smette, A.; Tokunaga, A.; Khayat, A.; Encrenaz, T.; Hartogh, P.

    2013-03-01

    Is Mars actively releasing organic and other minor gases into the atmosphere? We present a comprehensive search for trace species on Mars, targeting multiple volatile organic species (CH4, CH3OH, H2CO, C2H6, C2H2, C2H4), hydroperoxyl (HO2), several nitrogen compounds (N2O, NH3, HCN), and two chlorine species (HCl, CH3Cl) through their rovibrational spectra in the 2.8-3.7 μm spectral region. The data were acquired over a period of 4 years (2006-2010) using powerful infrared high-resolution spectrometers (CRIRES, NIRSPEC, CSHELL) at high-altitude observatories (VLT, Keck-2, NASA-IRTF), and span a broad range of seasons, Doppler shifts and spatial coverage. Here, we present results from a selection of high-quality spectra obtained on four separate dates, representing a fraction of our search space. For most of these species we derived the most stringent upper limits ever obtained, and because the targeted gases have substantially different resident lifetimes in the Martian atmosphere (from hours to centuries), our measurements not only test for current release but also provide stringent limits on the quiescent levels. In particular, we sampled the same regions where plumes of methane have been recently observed (e.g., Syrtis Major and Valles Marineris), allowing us to test for seasonal and temporal variability.

  16. Selective adsorption for removal of nitrogen compounds from hydrocarbon streams over carbon-based adsorbents

    NASA Astrophysics Data System (ADS)

    Almarri, Masoud S.

    The ultimate goal of this thesis is to develop a fundamental understanding of the role of surface oxygen functional groups on carbon-based adsorbents in the adsorption of nitrogen compounds that are known to be present in liquid fuels. N2 adsorption was used to characterize pore structures. The surface chemical properties of the adsorbents were characterized by X-ray photoelectron spectroscopy (XPS) and temperature-programmed desorption (TPD) techniques with a mass spectrometer to identify and quantify the type and concentration of oxygen functional groups on the basis of CO2 and CO evolution profiles. It was found that although surface area and pore size distribution are important for the adsorption process, they are not primary factors in the adsorption of nitrogen compounds. On the other hand, both the type and concentration of surface oxygen-containing functional groups play an important role in determining adsorptive denitrogenation performance. Higher concentrations of the oxygen functional groups on the adsorbents resulted in a higher adsorption capacity for the nitrogen compounds. A fundamental insight was gained into the contributions of different oxygen functional groups by analyzing the changes in the monolayer maximum adsorption capacity, qm, and the adsorption constant, K, for nitrogen compounds on different activated carbons. Acidic functional groups such as carboxylic acids and carboxylic anhydrides appear to contribute more to the adsorption of quinoline, while the basic oxygen functional groups such as carbonyls and quinones enhance the adsorption of indole. Despite the high number of publications on the adsorptive desulfurization of liquid hydrocarbon fuels, these studies did not consider the presence of coexisting nitrogen compounds. It is well-known that, to achieve ultraclean diesel fuel, sulfur must be reduced to a very low level, where the concentrations of nitrogen and sulfur compounds are comparable. The adsorptive denitrogenation and

  17. Nutrients, organic compounds, and mercury in the Meduxnekeag River watershed, Maine, 2003

    USGS Publications Warehouse

    Schalk, Charles W.; Tornes, Lan

    2005-01-01

    In 2003, the U.S. Geological Survey, in cooperation with the Houlton Band of Maliseet Indians, sampled streambed sediments and surface water of the Meduxnekeag River watershed in northeastern Maine under various hydrologic conditions for nutrients, hydrophobic organic compounds, and mercury. Nutrients were sampled to address concerns related to summer algal blooms, and organic compounds and mercury were sampled to address concerns about regional depositional patterns and overall watershed quality. In most surface-water samples, phosphorus was not detected or was detected at concentrations below the minimum reporting limit. Nitrate and organic nitrogen were detected in every surface-water sample for which they were analyzed; the highest concentration of total nitrogen was 0.75 milligrams per liter during low flow. Instantaneous nitrogen loads and yields were calculated at four stations for two sampling events. These data indicate that the part of the watershed that includes Houlton, its wastewater-treatment plant, and four small urban brooks may have contributed high concentrations of nitrate to Meduxnekeag River during the high flows on April 23-24 and high concentrations of both organic and nitrate nitrogen on June 2-3. Mercury was detected in all three bed-sediment samples for which it was analyzed; concentrations were similar to those reported from regional studies. Notable organic compounds detected in bed sediments included p,p'-DDE and p,p'-DDT (pesticides of the DDT family) and several polycyclic aromatic hydrocarbons. Polychlorinated biphenyls (PCBs) and phthalates were not detected in any sample, whereas p-cresol was the only phenolic compound detected. Phosphorus was detected at concentrations below 700 milligrams per kilogram in each bed-sediment sample for which it was analyzed. Data were insufficient to establish whether the lack of large algal blooms in 2003 was related to low concentrations of phosphorus.

  18. [Characteristics of organic nitrogen mineralization in organic waste compost-amended soil].

    PubMed

    Zhang, Xu; Xi, Bei-Dou; Zhao, Yue; Wei, Zi-Min; Li, Yang; Zhao, Xin-Yu

    2013-06-01

    A laboratory aerobic incubation experiment was conducted under a constant temperature to investigate the differentiation rule of nitrogen form among soils amended with different organic wastes composted with food waste, chicken manure, cow manure, domestic waste, vegetable residue, sludge, turf and tomato residue. Experiment utilized soils amended with 0%, 5% and 50% (m/m) of eight organic waste composts. The purpose was to understand the effect of different organic wastes on nitrogen mineralization in soil. This study deals with eight organic waste compost treatments could rapidly increase NH4(+) -N concentrations, reduce the NO3(-)-N concentrations and promote nitrogen mineralization in soil after 3-4 weeks incubation. All parameter tended to be stable. The improved amplitude of the same compost-amended soil: 30% compost treatments > 15% compost treatments > 5% compost treatments. Within the same proportion, chicken manure compost, turf compost and sludge compost product treatments' relative N mineralization was higher than other compost product treatments, and the chicken manure compost treatment's relative N mineralization was significantly higher than other compost product treatments. Food waste compost and vegetable residue compost product treatments' mineralization was low, the lowest was domestic waste compost product treatment. All compost treatments could significantly improve the values of potentially mineralizable nitrogen(N(0)), mineralization rate (k), and promote nitrogen mineralization in soil. The results illustrated that the effect of organic waste compost on the mineralization of nitrogen varied with types of compost and the amount of input compost.

  19. Seasonal changes in carbon and nitrogen compound concentrations in a Quercus petraea chronosequence.

    PubMed

    Gilson, Angélique; Barthes, Laure; Delpierre, Nicolas; Dufrêne, Éric; Fresneau, Chantal; Bazot, Stéphane

    2014-07-01

    Forest productivity declines with tree age. This decline may be due to changes in metabolic functions, resource availability and/or changes in resource allocation (between growth, reproduction and storage) with tree age. Carbon and nitrogen remobilization/storage processes are key to tree growth and survival. However, studies of the effects of tree age on these processes are scarce and have not yet considered seasonal carbon and nitrogen variations in situ. This study was carried out in a chronosequence of sessile oak (Quercus petraea Liebl.) for 1 year to survey the effects of tree age on the seasonal changes of carbon and nitrogen compounds in several tree compartments, focusing on key phenological stages. Our results highlight a general pattern of carbon and nitrogen function at all tree ages, with carbon reserve remobilization at budburst for growth, followed by carbon reserve formation during the leafy season and carbon reserve use during winter for maintenance. The variation in concentrations of nitrogen compounds shows less amplitude than that of carbon compounds. Storage as proteins occurs later, and mainly depends on leaf nitrogen remobilization and root uptake in autumn. We highlight several differences between tree age groups, in particular the loss of carbon storage function of fine and medium-sized roots with tree ageing. Moreover, the pattern of carbon compound accumulation in branches supports the hypothesis of a preferential allocation of carbon towards growth until the end of wood formation in juvenile trees, at the expense of the replenishment of carbon stores, while mature trees start allocating carbon to storage right after budburst. Our results demonstrate that at key phenological stages, physiological and developmental functions differ with tree age, and together with environmental conditions, influence the carbon and nitrogen concentration variations in sessile oaks.

  20. NITROGEN DEPOSITION AND ORGANIC MATTER MANIPULATIONS AFFECT GROSS AND NET NITROGEN TRANSFORMATIONS IN TWO TEMPERATE FORESTS SOILS

    EPA Science Inventory

    Soil nitrogen transformations are intricately linked to carbon transformations. We utilized two existing organic matter manipulation sites in western Oregon, USA and Hungary to investigate these linkages. Our questions were: 1) Does the quantity and quality of organic matter af...

  1. FIELD SCREENING FOR HALOGENATED VOLATILE ORGANIC COMPOUNDS

    SciTech Connect

    John F. Schabron; Joseph F. Rovani, Jr.; Theresa M. Bomstad

    2003-07-01

    Western Research Institute (WRI) is continuing work toward the development of new screening methodology and a test kit to measure halogenated volatile organic compounds (VOCs) in the field. Heated diode and corona discharge sensors are commonly used to detect leaks of refrigerants from air conditioners, freezers, and refrigerators. They are both selective to the presence of halogens. In prior work, the devices were tested for response to carbon tetrachloride, heptane, toluene, and water vapors. In the current work, sensor response was evaluated with sixteen halogenated VOCs relative to carbon tetrachloride. The results show that the response of the various chlorinated VOCs is within an order of magnitude of the response to carbon tetrachloride for each of the sensors. Thus, for field screening a single response factor can be used. Both types of leak detectors are being further modified to provide an on-board LCD signal readout, which is related to VOC concentration. The units will be fully portable and will operate with 115-V line or battery power. Signal background, noise level, and response data on the Bacharach heated diode detector and the TIF corona discharge detector show that when the response curves are plotted against the log of concentration, the plot is linear to the upper limit for the particular unit, with some curvature at lower levels. When response is plotted directly against concentration, the response is linear at the low end and is curved at the high end. The dynamic ranges for carbon tetrachloride of the two devices from the lower detection limit (S/N=2) to signal saturation are 4-850 vapor parts per million (vppm) for the corona discharge unit and 0.01-70 vppm for the heated diode unit. Additional circuit modifications are being made to lower the detection limit and increase the dynamic response range of the corona discharge unit. The results indicate that both devices show potential utility for future analytical method development work toward

  2. Germination of Aspergillus niger conidia is triggered by nitrogen compounds related to L-amino acids.

    PubMed

    Hayer, Kimran; Stratford, Malcolm; Archer, David B

    2014-10-01

    Conidial germination is fundamentally important to the growth and dissemination of most fungi. It has been previously shown (K. Hayer, M. Stratford, and D. B. Archer, Appl. Environ. Microbiol. 79:6924-6931, 2013, http://dx.doi.org/10.1128/AEM.02061-13), using sugar analogs, that germination is a 2-stage process involving triggering of germination and then nutrient uptake for hyphal outgrowth. In the present study, we tested this 2-stage germination process using a series of nitrogen-containing compounds for the ability to trigger the breaking of dormancy of Aspergillus niger conidia and then to support the formation of hyphae by acting as nitrogen sources. Triggering and germination were also compared between A. niger and Aspergillus nidulans using 2-deoxy-D-glucose (trigger), D-galactose (nontrigger in A. niger but trigger in A. nidulans), and an N source (required in A. niger but not in A. nidulans). Although most of the nitrogen compounds studied served as nitrogen sources for growth, only some nitrogen compounds could trigger germination of A. niger conidia, and all were related to L-amino acids. Using L-amino acid analogs without either the amine or the carboxylic acid group revealed that both the amine and carboxylic acid groups were essential for an L-amino acid to serve as a trigger molecule. Generally, conidia were able to sense and recognize nitrogen compounds that fitted into a specific size range. There was no evidence of uptake of either triggering or nontriggering compounds over the first 90 min of A. niger conidial germination, suggesting that the germination trigger sensors are not located within the spore.

  3. 40 CFR 60.462 - Standards for volatile organic compounds.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 6 2010-07-01 2010-07-01 false Standards for volatile organic compounds. 60.462 Section 60.462 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Coil Surface Coating § 60.462 Standards for volatile organic compounds. (a) On and after the date...

  4. 40 CFR 60.492 - Standards for volatile organic compounds.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 7 2013-07-01 2013-07-01 false Standards for volatile organic compounds. 60.492 Section 60.492 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Beverage Can Surface Coating Industry § 60.492 Standards for volatile organic compounds. On or after...

  5. 40 CFR 60.582 - Standard for volatile organic compounds.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 7 2014-07-01 2014-07-01 false Standard for volatile organic compounds. 60.582 Section 60.582 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Flexible Vinyl and Urethane Coating and Printing § 60.582 Standard for volatile organic compounds. (a)...

  6. 40 CFR 60.462 - Standards for volatile organic compounds.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 7 2014-07-01 2014-07-01 false Standards for volatile organic compounds. 60.462 Section 60.462 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Coil Surface Coating § 60.462 Standards for volatile organic compounds. (a) On and after the date...

  7. 40 CFR 60.462 - Standards for volatile organic compounds.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 6 2011-07-01 2011-07-01 false Standards for volatile organic compounds. 60.462 Section 60.462 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Coil Surface Coating § 60.462 Standards for volatile organic compounds. (a) On and after the date...

  8. 40 CFR 60.602 - Standard for volatile organic compounds.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 6 2010-07-01 2010-07-01 false Standard for volatile organic compounds. 60.602 Section 60.602 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Synthetic Fiber Production Facilities § 60.602 Standard for volatile organic compounds. On and after...

  9. 40 CFR 60.462 - Standards for volatile organic compounds.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 7 2013-07-01 2013-07-01 false Standards for volatile organic compounds. 60.462 Section 60.462 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Coil Surface Coating § 60.462 Standards for volatile organic compounds. (a) On and after the date...

  10. 40 CFR 60.712 - Standards for volatile organic compounds.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 6 2011-07-01 2011-07-01 false Standards for volatile organic compounds. 60.712 Section 60.712 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Magnetic Tape Coating Facilities § 60.712 Standards for volatile organic compounds. Each owner or...

  11. 40 CFR 60.622 - Standards for volatile organic compounds.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 7 2014-07-01 2014-07-01 false Standards for volatile organic compounds. 60.622 Section 60.622 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Petroleum Dry Cleaners § 60.622 Standards for volatile organic compounds. (a) Each affected...

  12. 40 CFR 60.452 - Standard for volatile organic compounds.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 6 2011-07-01 2011-07-01 false Standard for volatile organic compounds. 60.452 Section 60.452 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Industrial Surface Coating: Large Appliances § 60.452 Standard for volatile organic compounds. On or...

  13. 40 CFR 60.582 - Standard for volatile organic compounds.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 6 2010-07-01 2010-07-01 false Standard for volatile organic compounds. 60.582 Section 60.582 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Flexible Vinyl and Urethane Coating and Printing § 60.582 Standard for volatile organic compounds. (a)...

  14. 40 CFR 60.492 - Standards for volatile organic compounds.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 6 2011-07-01 2011-07-01 false Standards for volatile organic compounds. 60.492 Section 60.492 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Beverage Can Surface Coating Industry § 60.492 Standards for volatile organic compounds. On or after...

  15. 40 CFR 60.602 - Standard for volatile organic compounds.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 7 2013-07-01 2013-07-01 false Standard for volatile organic compounds. 60.602 Section 60.602 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Synthetic Fiber Production Facilities § 60.602 Standard for volatile organic compounds. On and after...

  16. 40 CFR 60.742 - Standards for volatile organic compounds.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 6 2011-07-01 2011-07-01 false Standards for volatile organic compounds. 60.742 Section 60.742 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Polymeric Coating of Supporting Substrates Facilities § 60.742 Standards for volatile organic compounds....

  17. 40 CFR 60.452 - Standard for volatile organic compounds.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 7 2014-07-01 2014-07-01 false Standard for volatile organic compounds. 60.452 Section 60.452 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Industrial Surface Coating: Large Appliances § 60.452 Standard for volatile organic compounds. On or...

  18. 40 CFR 60.622 - Standards for volatile organic compounds.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 6 2010-07-01 2010-07-01 false Standards for volatile organic compounds. 60.622 Section 60.622 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Petroleum Dry Cleaners § 60.622 Standards for volatile organic compounds. (a) Each affected...

  19. 40 CFR 60.622 - Standards for volatile organic compounds.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 6 2011-07-01 2011-07-01 false Standards for volatile organic compounds. 60.622 Section 60.622 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Petroleum Dry Cleaners § 60.622 Standards for volatile organic compounds. (a) Each affected...

  20. 40 CFR 60.452 - Standard for volatile organic compounds.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 7 2012-07-01 2012-07-01 false Standard for volatile organic compounds. 60.452 Section 60.452 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Industrial Surface Coating: Large Appliances § 60.452 Standard for volatile organic compounds. On or...

  1. 40 CFR 60.452 - Standard for volatile organic compounds.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 6 2010-07-01 2010-07-01 false Standard for volatile organic compounds. 60.452 Section 60.452 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Industrial Surface Coating: Large Appliances § 60.452 Standard for volatile organic compounds. On or...

  2. 40 CFR 60.582 - Standard for volatile organic compounds.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 7 2013-07-01 2013-07-01 false Standard for volatile organic compounds. 60.582 Section 60.582 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Flexible Vinyl and Urethane Coating and Printing § 60.582 Standard for volatile organic compounds. (a)...

  3. 40 CFR 60.582 - Standard for volatile organic compounds.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 6 2011-07-01 2011-07-01 false Standard for volatile organic compounds. 60.582 Section 60.582 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Flexible Vinyl and Urethane Coating and Printing § 60.582 Standard for volatile organic compounds. (a)...

  4. 40 CFR 60.462 - Standards for volatile organic compounds.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 7 2012-07-01 2012-07-01 false Standards for volatile organic compounds. 60.462 Section 60.462 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Coil Surface Coating § 60.462 Standards for volatile organic compounds. (a) On and after the date...

  5. 40 CFR 60.492 - Standards for volatile organic compounds.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 7 2012-07-01 2012-07-01 false Standards for volatile organic compounds. 60.492 Section 60.492 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Beverage Can Surface Coating Industry § 60.492 Standards for volatile organic compounds. On or after...

  6. 40 CFR 60.622 - Standards for volatile organic compounds.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 7 2013-07-01 2013-07-01 false Standards for volatile organic compounds. 60.622 Section 60.622 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Petroleum Dry Cleaners § 60.622 Standards for volatile organic compounds. (a) Each affected...

  7. 40 CFR 60.712 - Standards for volatile organic compounds.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 7 2014-07-01 2014-07-01 false Standards for volatile organic compounds. 60.712 Section 60.712 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Magnetic Tape Coating Facilities § 60.712 Standards for volatile organic compounds. Each owner or...

  8. 40 CFR 60.622 - Standards for volatile organic compounds.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 7 2012-07-01 2012-07-01 false Standards for volatile organic compounds. 60.622 Section 60.622 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Petroleum Dry Cleaners § 60.622 Standards for volatile organic compounds. (a) Each affected...

  9. 40 CFR 60.722 - Standards for volatile organic compounds.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 7 2013-07-01 2013-07-01 false Standards for volatile organic compounds. 60.722 Section 60.722 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... volatile organic compounds. (a) Each owner or operator of any affected facility which is subject to...

  10. 40 CFR 60.602 - Standard for volatile organic compounds.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 7 2014-07-01 2014-07-01 false Standard for volatile organic compounds. 60.602 Section 60.602 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Synthetic Fiber Production Facilities § 60.602 Standard for volatile organic compounds. On and after...

  11. 40 CFR 60.742 - Standards for volatile organic compounds.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 7 2014-07-01 2014-07-01 false Standards for volatile organic compounds. 60.742 Section 60.742 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Polymeric Coating of Supporting Substrates Facilities § 60.742 Standards for volatile organic compounds....

  12. 40 CFR 60.602 - Standard for volatile organic compounds.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 6 2011-07-01 2011-07-01 false Standard for volatile organic compounds. 60.602 Section 60.602 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Synthetic Fiber Production Facilities § 60.602 Standard for volatile organic compounds. On and after...

  13. 40 CFR 60.712 - Standards for volatile organic compounds.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 7 2013-07-01 2013-07-01 false Standards for volatile organic compounds. 60.712 Section 60.712 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Magnetic Tape Coating Facilities § 60.712 Standards for volatile organic compounds. Each owner or...

  14. 40 CFR 60.602 - Standard for volatile organic compounds.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 7 2012-07-01 2012-07-01 false Standard for volatile organic compounds. 60.602 Section 60.602 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Synthetic Fiber Production Facilities § 60.602 Standard for volatile organic compounds. On and after...

  15. 40 CFR 60.582 - Standard for volatile organic compounds.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 7 2012-07-01 2012-07-01 false Standard for volatile organic compounds. 60.582 Section 60.582 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Flexible Vinyl and Urethane Coating and Printing § 60.582 Standard for volatile organic compounds. (a)...

  16. 40 CFR 60.742 - Standards for volatile organic compounds.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 7 2012-07-01 2012-07-01 false Standards for volatile organic compounds. 60.742 Section 60.742 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Polymeric Coating of Supporting Substrates Facilities § 60.742 Standards for volatile organic compounds....

  17. 40 CFR 60.712 - Standards for volatile organic compounds.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 7 2012-07-01 2012-07-01 false Standards for volatile organic compounds. 60.712 Section 60.712 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Magnetic Tape Coating Facilities § 60.712 Standards for volatile organic compounds. Each owner or...

  18. 40 CFR 60.492 - Standards for volatile organic compounds.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 7 2014-07-01 2014-07-01 false Standards for volatile organic compounds. 60.492 Section 60.492 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Beverage Can Surface Coating Industry § 60.492 Standards for volatile organic compounds. On or after...

  19. 40 CFR 60.742 - Standards for volatile organic compounds.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 7 2013-07-01 2013-07-01 false Standards for volatile organic compounds. 60.742 Section 60.742 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Polymeric Coating of Supporting Substrates Facilities § 60.742 Standards for volatile organic compounds....

  20. 40 CFR 60.492 - Standards for volatile organic compounds.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 6 2010-07-01 2010-07-01 false Standards for volatile organic compounds. 60.492 Section 60.492 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Beverage Can Surface Coating Industry § 60.492 Standards for volatile organic compounds. On or after...

  1. 40 CFR 60.722 - Standards for volatile organic compounds.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 7 2014-07-01 2014-07-01 false Standards for volatile organic compounds. 60.722 Section 60.722 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... volatile organic compounds. (a) Each owner or operator of any affected facility which is subject to...

  2. 40 CFR 60.722 - Standards for volatile organic compounds.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 6 2011-07-01 2011-07-01 false Standards for volatile organic compounds. 60.722 Section 60.722 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... volatile organic compounds. (a) Each owner or operator of any affected facility which is subject to...

  3. 40 CFR 60.722 - Standards for volatile organic compounds.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 6 2010-07-01 2010-07-01 false Standards for volatile organic compounds. 60.722 Section 60.722 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... volatile organic compounds. (a) Each owner or operator of any affected facility which is subject to...

  4. 40 CFR 60.722 - Standards for volatile organic compounds.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 7 2012-07-01 2012-07-01 false Standards for volatile organic compounds. 60.722 Section 60.722 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... volatile organic compounds. (a) Each owner or operator of any affected facility which is subject to...

  5. 40 CFR 60.452 - Standard for volatile organic compounds.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 7 2013-07-01 2013-07-01 false Standard for volatile organic compounds. 60.452 Section 60.452 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Industrial Surface Coating: Large Appliances § 60.452 Standard for volatile organic compounds. On or...

  6. 40 CFR 60.712 - Standards for volatile organic compounds.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 6 2010-07-01 2010-07-01 false Standards for volatile organic compounds. 60.712 Section 60.712 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Magnetic Tape Coating Facilities § 60.712 Standards for volatile organic compounds. Each owner or...

  7. 40 CFR 60.742 - Standards for volatile organic compounds.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 6 2010-07-01 2010-07-01 false Standards for volatile organic compounds. 60.742 Section 60.742 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Polymeric Coating of Supporting Substrates Facilities § 60.742 Standards for volatile organic compounds....

  8. A Systematic Presentation of Organic Phosphorus and Sulfur Compounds.

    ERIC Educational Resources Information Center

    Hendrickson, James B.

    1985-01-01

    Because the names, interrelations, and oxidation levels of the organic compounds of phosphorus and sulfur tend to confuse students, a simple way to organize these compounds has been developed. The system consists of grouping them by oxidation state and extent of carbon substitution. (JN)

  9. A novel membrane distillation-thermophilic bioreactor system: biological stability and trace organic compound removal.

    PubMed

    Wijekoon, Kaushalya C; Hai, Faisal I; Kang, Jinguo; Price, William E; Guo, Wenshan; Ngo, Hao H; Cath, Tzahi Y; Nghiem, Long D

    2014-05-01

    The removal of trace organic compounds (TrOCs) by a novel membrane distillation-thermophilic bioreactor (MDBR) system was examined. Salinity build-up and the thermophilic conditions to some extent adversely impacted the performance of the bioreactor, particularly the removal of total nitrogen and recalcitrant TrOCs. While most TrOCs were well removed by the thermophilic bioreactor, compounds containing electron withdrawing functional groups in their molecular structure were recalcitrant to biological treatment and their removal efficiency by the thermophilic bioreactor was low (0-53%). However, the overall performance of the novel MDBR system with respect to the removal of total organic carbon, total nitrogen, and TrOCs was high and was not significantly affected by the conditions of the bioreactor. All TrOCs investigated here were highly removed (>95%) by the MDBR system. Biodegradation, sludge adsorption, and rejection by MD contribute to the removal of TrOCs by MDBR treatment.

  10. Soluble, semivolatile phenol and nitrogen compounds in milk-processing wastewaters.

    PubMed

    Verheyen, V; Cruickshank, A; Wild, K; Heaven, M W; McGee, R; Watkins, M; Nash, D

    2009-07-01

    Potable water is an essential and major input in processing our food supplies, and the continued growth in food manufacturing is placing increased pressure on this limited resource. Recycling and reuse of factory wastewater can lessen potable water use but requires a detailed understanding of wastewater properties. This study uses solid-phase extraction techniques with gas chromatography-mass spectrometry analysis to investigate trace-level semivolatile organic species in various waste and reference waters associated with the Burra Foods milk-processing plant located in Southeastern Australia. Our focus was on contaminants containing phenolic and heterocyclic nitrogen functional groups, which, because of their toxicity and persistence, may limit options for water recycling and reuse. Effluent from the wastewater treatment plant of the factory showed both the highest soluble carbon burden (47 mg/kg) and concentrations of target compounds. The target species found in these effluents included methyl phenol (13 mg/kg), hydroxy indole (9.8 mg/kg), synthetic tolyltriazoles (5.1 mg/kg) and alkyl phenol ethoxylates (0.2 mg/kg). Given the environmental stability of the tolyltriazoles, they may act as chemical markers where these effluents are used for purposes such as irrigation. Milk evaporator condensate waters, in contrast to the effluent, contained very few target species, with only low levels of pyrrolidine and piperidine derivatives such as ethylglutarimide (450 mug/L) detected. Although there were fewer target microcontaminants overall in the potable and creek reference waters, these samples had characteristic profiles. The potable water analysis revealed hydroxy cineole (2.1 microg/L) and the creek analysis revealed dichlorohydroxyacetophenone (0.3 microg/L), which were not detected in other waters. The compounds found in the wastewaters are likely to have been derived from milk or synthetic chemicals used in factory operations. The presence of nitrogen compounds in

  11. A general, cryogenically-based analytical technique for the determination of trace quantities of volatile organic compounds in the atmosphere

    NASA Technical Reports Server (NTRS)

    Coleman, R. A.; Cofer, W. R., III; Edahl, R. A., Jr.

    1985-01-01

    An analytical technique for the determination of trace (sub-ppbv) quantities of volatile organic compounds in air was developed. A liquid nitrogen-cooled trap operated at reduced pressures in series with a Dupont Nafion-based drying tube and a gas chromatograph was utilized. The technique is capable of analyzing a variety of organic compounds, from simple alkanes to alcohols, while offering a high level of precision, peak sharpness, and sensitivity.

  12. Environmentally friendly organic synthesis using bismuth(III) compounds.

    PubMed

    Krabbe, Scott W; Mohan, Ram S

    2012-01-01

    With increasing environmental concerns, the need for environmentally friendly organic synthesis has gained increased importance. In this regard, bismuth(III) compounds are especially attractive as "green" reagents and catalysts for organic synthesis. Bismuth(III) compounds are remarkably nontoxic, relatively air and moisture stable, and easy to handle. The contributions from our laboratory in the last 5 years in the field of applications of bismuth(III) compounds as catalysts are presented.

  13. Volatile organic compounds in the atmosphere of Mexico City

    NASA Astrophysics Data System (ADS)

    Garzón, Jessica P.; Huertas, José I.; Magaña, Miguel; Huertas, María E.; Cárdenas, Beatriz; Watanabe, Takuro; Maeda, Tsuneaki; Wakamatsu, Shinji; Blanco, Salvador

    2015-10-01

    The Mexico City Metropolitan Area (MCMA) is one of the most polluted megacities in North America. Therefore, it is an excellent benchmark city to understand atmospheric chemistry and to implement pilot countermeasures. Air quality in the MCMA is not within acceptable levels, mainly due to high ground levels of ozone (O3). Tropospheric O3 is a secondary pollutant formed from the oxidation of volatile organic compounds (VOCs) in the presence of nitrogen oxides and sunlight. To gain a better understanding of O3 formation in megacities, evaluate the effectiveness of already-implemented countermeasures, and identify new cost-effective alternatives to reduce tropospheric O3 concentrations, researchers and environmental authorities require updated concentrations for a broader range of VOCs. Moreover, in an effort to protect human health and the environment, it is important to understand which VOCs exceed reference safe values or most contribute to O3 formation, as well as to identify the most probable emission sources of those VOCs. In this work, 64 VOCs, including 36 toxic VOCs, were measured at four sites in the MCMA during 2011-2012. VOCs related to liquefied petroleum gas leakages exhibited the highest concentrations. Toxic VOCs with the highest average concentrations were acetone and ethanol. The toxic VOC benzene represented the highest risk to Mexican citizens, and toluene contributed the most to O3 formation. Correlation analysis indicated that the measured VOCs come from vehicular emissions and solvent-related industrial sources.

  14. Analysis of Volatile Organic Compounds in a Controlled Environment: Ethylene Gas Measurement Studies on Radish

    NASA Technical Reports Server (NTRS)

    Kong, Suk Bin

    2001-01-01

    Volatile organic compound(VOC), ethylene gas, was characterized and quantified by GC/FID. 20-50 ppb levels were detected during the growth stages of radish. SPME could be a good analytical tool for the purpose. Low temperature trapping method using dry ice/diethyl ether and liquid nitrogen bath was recommended for the sampling process for GC/PID and GC/MS analysis.

  15. Pyrolysis of organic compounds in the presence of ammonia The Viking Mars lander site alteration experiment

    NASA Technical Reports Server (NTRS)

    Holzer, G.; Oro, J.

    1977-01-01

    The influence of ammonia on the pyrolysis pattern of selected organic substances sorbed on an inorganic phase was investigated. The thermal degradation products were identified by gas chromatography-mass spectrometry. The feasibility of this technique was tested on a meteoritic sample. All substances examined react with ammonia at the pyrolysis temperature of 500 C, the major products being nitriles and heterocyclic compounds in which nitrogen was incorporated. Based on these results, a model for the non-equilibrium production of organic compounds on Jupiter is discussed. The investigation was performed in connection with the Viking lander molecular analysis. The results obtained indicate that the concentrations of ammonia in the retrorocket fuel exhaust would have been probably too small to produce significant changes in the Martian soil organic compounds if any were found.

  16. COMETARY SCIENCE. Organic compounds on comet 67P/Churyumov-Gerasimenko revealed by COSAC mass spectrometry.

    PubMed

    Goesmann, Fred; Rosenbauer, Helmut; Bredehöft, Jan Hendrik; Cabane, Michel; Ehrenfreund, Pascale; Gautier, Thomas; Giri, Chaitanya; Krüger, Harald; Le Roy, Léna; MacDermott, Alexandra J; McKenna-Lawlor, Susan; Meierhenrich, Uwe J; Muñoz Caro, Guillermo M; Raulin, Francois; Roll, Reinhard; Steele, Andrew; Steininger, Harald; Sternberg, Robert; Szopa, Cyril; Thiemann, Wolfram; Ulamec, Stephan

    2015-07-31

    Comets harbor the most pristine material in our solar system in the form of ice, dust, silicates, and refractory organic material with some interstellar heritage. The evolved gas analyzer Cometary Sampling and Composition (COSAC) experiment aboard Rosetta's Philae lander was designed for in situ analysis of organic molecules on comet 67P/Churyumov-Gerasimenko. Twenty-five minutes after Philae's initial comet touchdown, the COSAC mass spectrometer took a spectrum in sniffing mode, which displayed a suite of 16 organic compounds, including many nitrogen-bearing species but no sulfur-bearing species, and four compounds—methyl isocyanate, acetone, propionaldehyde, and acetamide—that had not previously been reported in comets.

  17. High fluvial export of dissolved organic nitrogen from a peatland catchment with elevated inorganic nitrogen deposition.

    PubMed

    Edokpa, D A; Evans, M G; Rothwell, J J

    2015-11-01

    This study investigates seasonal concentrations and fluxes of nitrogen (N) species under stormflow and baseflow conditions in the peat dominated Kinder River catchment, south Pennines, UK. This upland region has experienced decades of high atmospheric inorganic N deposition. Water samples were collected fortnightly over one year, in combination with high resolution stormflow sampling and discharge monitoring. The results reveal that dissolved organic nitrogen (DON) constitutes ~54% of the estimated annual total dissolved nitrogen (TDN) flux (14.3 kg N ha(-1) yr(-1)). DON cycling in the catchment is influenced by hydrological and biological controls, with greater concentrations under summer stormflow conditions. Dissolved organic carbon (DOC) and DON are closely coupled, with positive correlations observed during spring, summer and autumn stormflow conditions. A low annual mean DOC:DON ratio (<25) and elevated dissolved inorganic N concentrations (up to 63μmoll(-1) in summer) suggest that the Kinder catchment is at an advanced stage of N saturation. This study reveals that DON is a significant component of TDN in peatland fluvial systems that receive high atmospheric inputs of inorganic N.

  18. Preliminary classification of characteristic organic gunshot residue compounds.

    PubMed

    Goudsmits, Ellen; Sharples, George P; Birkett, Jason W

    2016-12-01

    For the first time, a classification system for organic gunshot residue (OGSR) compounds with respect to the confirmation of OGSR materials is presented. There are 136 compounds considered to be associated with OGSR that have been highlighted in the literature. Many of these compounds could be classified as being ubiquitous in the environment and thus their detection as characteristic components of OGSR could cause issues with the interpretation of chemical ballistic evidence. The proposed system aims to address this problem by classifying OGSR compounds based on their forensic relevance with respect to the confirmation of GSR materials. To increase the forensic relevance of such a system, the large number of OGSR compounds reported in the literature has been decreased to 20 OGSR compounds based on the organic chemical composition of over 200 propellant powders. Occupational and environmental materials also associated with OGSR compounds have been considered.

  19. Organic Compounds in Circumstellar and Interstellar Environments

    NASA Astrophysics Data System (ADS)

    Kwok, Sun

    2015-06-01

    Recent research has discovered that complex organic matter is prevalent throughout the Universe. In the Solar System, it is found in meteorites, comets, interplanetary dust particles, and planetary satellites. Spectroscopic signatures of organics with aromatic/aliphatic structures are also found in stellar ejecta, diffuse interstellar medium, and external galaxies. From space infrared spectroscopic observations, we have found that complex organics can be synthesized in the late stages of stellar evolution. Shortly after the nuclear synthesis of the element carbon, organic gas-phase molecules are formed in the stellar winds, which later condense into solid organic particles. This organic synthesis occurs over very short time scales of about a thousand years. In order to determine the chemical structures of these stellar organics, comparisons are made with particles produced in the laboratory. Using the technique of chemical vapor deposition, artificial organic particles have been created by injecting energy into gas-phase hydrocarbon molecules. These comparisons led us to believe that the stellar organics are best described as amorphous carbonaceous nanoparticles with mixed aromatic and aliphatic components. The chemical structures of the stellar organics show strong similarity to the insoluble organic matter found in meteorites. Isotopic analysis of meteorites and interplanetary dust collected in the upper atmospheres have revealed the presence of pre-solar grains similar to those formed in old stars. This provides a direct link between star dust and the Solar System and raises the possibility that the early Solar System was chemically enriched by stellar ejecta with the potential of influencing the origin of life on Earth.

  20. Organic compounds in circumstellar and interstellar environments.

    PubMed

    Kwok, Sun

    2015-06-01

    Recent research has discovered that complex organic matter is prevalent throughout the Universe. In the Solar System, it is found in meteorites, comets, interplanetary dust particles, and planetary satellites. Spectroscopic signatures of organics with aromatic/aliphatic structures are also found in stellar ejecta, diffuse interstellar medium, and external galaxies. From space infrared spectroscopic observations, we have found that complex organics can be synthesized in the late stages of stellar evolution. Shortly after the nuclear synthesis of the element carbon, organic gas-phase molecules are formed in the stellar winds, which later condense into solid organic particles. This organic synthesis occurs over very short time scales of about a thousand years. In order to determine the chemical structures of these stellar organics, comparisons are made with particles produced in the laboratory. Using the technique of chemical vapor deposition, artificial organic particles have been created by injecting energy into gas-phase hydrocarbon molecules. These comparisons led us to believe that the stellar organics are best described as amorphous carbonaceous nanoparticles with mixed aromatic and aliphatic components. The chemical structures of the stellar organics show strong similarity to the insoluble organic matter found in meteorites. Isotopic analysis of meteorites and interplanetary dust collected in the upper atmospheres have revealed the presence of pre-solar grains similar to those formed in old stars. This provides a direct link between star dust and the Solar System and raises the possibility that the early Solar System was chemically enriched by stellar ejecta with the potential of influencing the origin of life on Earth.

  1. Phosphatase hydrolysis of organic phosphorus compounds

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Phosphatases are diverse groups of enzymes that deserve special attention because of the significant roles they play in mineralizing organic phosphorus (P) into inorganic available form. For getting more insight on the enzymatically hydrolysis of organic P, in this work, we compared the catalytic pa...

  2. Extended structures and physicochemical properties of uranyl-organic compounds.

    PubMed

    Wang, Kai-Xue; Chen, Jie-Sheng

    2011-07-19

    The ability of uranium to undergo nuclear fission has been exploited primarily to manufacture nuclear weapons and to generate nuclear power. Outside of its nuclear physics, uranium also exhibits rich chemistry, and it forms various compounds with other elements. Among the uranium-bearing compounds, those with a uranium oxidation state of +6 are most common and a particular structural unit, uranyl UO(2)(2+) is usually involved in these hexavalent uranium compounds. Apart from forming solids with inorganic ions, the uranyl unit also bonds to organic molecules to generate uranyl-organic coordination materials. If appropriate reaction conditions are employed, uranyl-organic extended structures (1-D chains, 2-D layers, and 3-D frameworks) can be obtained. Research on uranyl-organic compounds with extended structures allows for the exploration of their rich structural chemistry, and such studies also point to potential applications such as in materials that could facilitate nuclear waste disposal. In this Account, we describe the structural features of uranyl-organic compounds and efforts to synthesize uranyl-organic compounds with desired structures. We address strategies to construct 3-D uranyl-organic frameworks through rational selection of organic ligands and the incorporation of heteroatoms. The UO(2)(2+) species with inactive U═O double bonds usually form bipyramidal polyhedral structures with ligands coordinated at the equatorial positions, and these polyhedra act as primary building units (PBUs) for the construction of uranyl-organic compounds. The geometry of the uranyl ions and the steric arrangements and functionalities of organic ligands can be exploited in the the design of uranyl--organic extended structures, We also focus on the investigation of the promising physicochemical properties of uranyl-organic compounds. Uranyl-organic materials with an extended structure may exhibit attractive properties, such as photoluminescence, photocatalysis

  3. Superhard composite materials including compounds of carbon and nitrogen deposited on metal and metal nitride carbide and carbonitride

    DOEpatents

    Wong, M.S.; Li, D.; Chung, Y.W.; Sproul, W.D.; Xi Chu; Barnett, S.A.

    1998-03-10

    A composite material having high hardness comprises a carbon nitrogen compound, such as CN{sub x} where x is greater than 0.1 and up to 1.33, deposited on a metal or metal compound selected to promote deposition of substantially crystalline CN{sub x}. The carbon nitrogen compound is deposited on a crystal plane of the metal or metal compound sufficiently lattice-matched with a crystal plane of the carbon nitrogen compound that the carbon nitrogen compound is substantially crystalline. A plurality of layers of the compounds can be formed in alternating sequence to provide a multi-layered, superlattice coating having a coating hardness in the range of 45--55 GPa, which corresponds to the hardness of a BN coating and approaches that of a diamond coating. 10 figs.

  4. Superhard composite materials including compounds of carbon and nitrogen deposited on metal and metal nitride, carbide and carbonitride

    DOEpatents

    Wong, M.S.; Li, D.; Chung, Y.W.; Sproul, W.D.; Chu, X.; Barnett, S.A.

    1998-07-07

    A composite material having high hardness comprises a carbon nitrogen compound, such as CN{sub x} where x is greater than 0.1 and up to 1.33, deposited on a metal or metal compound selected to promote deposition of substantially crystalline CN{sub x}. The carbon nitrogen compound is deposited on a crystal plane of the metal or metal compound sufficiently lattice-matched with a crystal plane of the carbon nitrogen compound that the carbon nitrogen compound is substantially crystalline. A plurality of layers of the compounds can be formed in alternating sequence to provide a multi-layered, superlattice coating having a coating hardness in the range of 45--55 GPa, which corresponds to the hardness of a BN coating and approaches that of a diamond coating. 10 figs.

  5. Superhard composite materials including compounds of carbon and nitrogen deposited on metal and metal nitride, carbide and carbonitride

    DOEpatents

    Wong, Ming-Show; Li, Dong; Chung, Yip-Wah; Sproul, William D.; Chu, Xi; Barnett, Scott A.

    1998-01-01

    A composite material having high hardness comprises a carbon nitrogen compound, such as CN.sub.x where x is greater than 0.1 and up to 1.33, deposited on a metal or metal compound selected to promote deposition of substantially crystalline CN.sub.x. The carbon nitrogen compound is deposited on a crystal plane of the metal or metal compound sufficiently lattice-matched with a crystal plane of the carbon nitrogen compound that the carbon nitrogen compound is substantially crystalline. A plurality of layers of the compounds can be formed in alternating sequence to provide a multi-layered, superlattice coating having a coating hardness in the range of 45-55 GPa, which corresponds to the hardness of a BN coating and approaches that of a diamond coating.

  6. Superhard composite materials including compounds of carbon and nitrogen deposited on metal and metal nitride carbide and carbonitride

    DOEpatents

    Wong, Ming-Show; Li, Dong; Chung, Yin-Wah; Sproul, William D.; Chu, Xi; Barnett, Scott A.

    1998-01-01

    A composite material having high hardness comprises a carbon nitrogen compound, such as CN.sub.x where x is greater than 0.1 and up to 1.33, deposited on a metal or metal compound selected to promote deposition of substantially crystalline CN.sub.x. The carbon nitrogen compound is deposited on a crystal plane of the metal or metal compound sufficiently lattice-matched with a crystal plane of the carbon nitrogen compound that the carbon nitrogen compound is substantially crystalline. A plurality of layers of the compounds can be formed in alternating sequence to provide a multi-layered, superlattice coating having a coating hardness in the range of 45-55 GPa, which corresponds to the hardness of a BN coating and approaches that of a diamond coating.

  7. Monitoring organic nitrogen species in the UT/LS - a new system for analysis of CARIBIC whole air samples

    NASA Astrophysics Data System (ADS)

    Sauvage, Carina; Thorenz, Ute; Baker, Angela; Brenninkmeijer, Carl; Williams, Jonathan

    2014-05-01

    The CARIBIC project is a unique program for long term and global scale monitoring of the atmosphere (http://www.caribic-atmospheric.com). An instrument container is installed monthly into a civil aircraft operated by Lufthansa (Airbus A 340-600) and makes atmospheric observations en route from Frankfurt, Germany to various destinations around the globe. In four to six long distance flights at a cruising altitude of 10 to 12 km online measurements of various atmospheric tracers are performed during the flight as well as whole air samples are taken with two different sampling units (116 samples in both glass and stainless steel canisters). These samples are routinely analyzed for greenhouse gases, non-methane hydrocarbons (NMHC) and halogenated compounds. Nitrogen containing compounds play various important roles in the atmosphere. Alkyl nitrates (RONO2) are products of the reaction of NMHC with OH and other oxidants in the presence of NO. They can provide information on the oxidative history of an air mass. Moreover they influence photolchemical ozone formation and act as a transport mechanism for reactive nitrogen. Less reactive nitrogen containing species such as HCN and acetonitrile are important markers for biomass burning, while organic amines are involved in gas to particle partitioning. Finally N2O is a long lived nitrogen containing gas important for the Earth's radiative budget. Regular measurements of such nitrogen compounds would therefore be a significant contribution to the CARIBIC data set. Especially for high altitude samples, in which the mixing ratios of many species are expected to be in the low ppt range, a highly sensitive method for analysis is required. Therefore a new system for measurement of nitrogen compounds has been built up, comprising a gas chromatograph (GC) using a nitrogen chemiluminescence detector (NCD). An important advantage of the NCD is that it is selective for nitrogen and equimolar. The nitrogen compounds are sequentially pre

  8. Analysis of microbial community and nitrogen transition with enriched nitrifying soil microbes for organic hydroponics.

    PubMed

    Saijai, Sakuntala; Ando, Akinori; Inukai, Ryuya; Shinohara, Makoto; Ogawa, Jun

    2016-06-27

    Nitrifying microbial consortia were enriched from bark compost in a water system by regulating the amounts of organic nitrogen compounds and by controlling the aeration conditions with addition of CaCO3 for maintaining suitable pH. Repeated enrichment showed reproducible mineralization of organic nitrogen via the conversion of ammonium ions ([Formula: see text]) and nitrite ions ([Formula: see text]) into nitrate ions ([Formula: see text]). The change in microbial composition during the enrichment was investigated by PCR-DGGE analysis with a focus on prokaryote, ammonia-oxidizing bacteria, nitrite-oxidizing bacteria, and eukaryote cell types. The microbial transition had a simple profile and showed clear relation to nitrogen ions transition. Nitrosomonas and Nitrobacter were mainly detected during [Formula: see text] and [Formula: see text] oxidation, respectively. These results revealing representative microorganisms acting in each ammonification and nitrification stages will be valuable for the development of artificial simple microbial consortia for organic hydroponics that consisted of identified heterotrophs and autotrophic nitrifying bacteria.

  9. Volatile organic compounds and some very volatile organic compounds in new and recently renovated buildings in Switzerland

    NASA Astrophysics Data System (ADS)

    Rothweiler, Heinz; Wäger, Patrick A.; Schlatter, Christian

    Indoor air in new of recently renovated buildings was analysed by using different sorbents and analytical methods. Increased values of total volatile organic compounds (TVOC) were found on Tenax TA (1.6-31.7 mg m -3). Compared to older buildings, the amount of oxygen-containing compounds (aldehydes, ketones, alcohols) especially was elevated. High hexanal concentrations were measured in a significant amount of the houses. Differences of compound patterns were found from building to building. Complaints about discomfort and negative health effects are expected due to volatile organic compounds (VOC) and very volatile organic compounds (VVOC), as well as from low natural ventilation rates in some newly occupied buildings. Odorous compounds (naphthalene, higher aldehydes and alcohols, capronic acid, etc.) were found mainly, but some irritants and suspected sensitizing agents were also found. At the present state of our investigation chemicals causing other known toxic effects do not seem to increase the toxic risk substantially.

  10. 40 CFR 60.542 - Standards for volatile organic compounds.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 7 2014-07-01 2014-07-01 false Standards for volatile organic... Rubber Tire Manufacturing Industry § 60.542 Standards for volatile organic compounds. (a) On and after...) For each green tire spraying operation where both water-based and organic solvent-based sprays...

  11. 40 CFR 60.542 - Standards for volatile organic compounds.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 7 2012-07-01 2012-07-01 false Standards for volatile organic... Rubber Tire Manufacturing Industry § 60.542 Standards for volatile organic compounds. (a) On and after...) For each green tire spraying operation where both water-based and organic solvent-based sprays...

  12. 40 CFR 60.542 - Standards for volatile organic compounds.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 6 2011-07-01 2011-07-01 false Standards for volatile organic... Rubber Tire Manufacturing Industry § 60.542 Standards for volatile organic compounds. (a) On and after...) For each green tire spraying operation where both water-based and organic solvent-based sprays...

  13. 40 CFR 60.542 - Standards for volatile organic compounds.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 7 2013-07-01 2013-07-01 false Standards for volatile organic... Rubber Tire Manufacturing Industry § 60.542 Standards for volatile organic compounds. (a) On and after...) For each green tire spraying operation where both water-based and organic solvent-based sprays...

  14. 40 CFR 60.542 - Standards for volatile organic compounds.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 6 2010-07-01 2010-07-01 false Standards for volatile organic... Rubber Tire Manufacturing Industry § 60.542 Standards for volatile organic compounds. (a) On and after...) For each green tire spraying operation where both water-based and organic solvent-based sprays...

  15. Modeling organic nitrogen conversions in activated sludge bioreactors.

    PubMed

    Makinia, Jacek; Pagilla, Krishna; Czerwionka, Krzysztof; Stensel, H David

    2011-01-01

    For biological nutrient removal (BNR) systems designed to maximize nitrogen removal, the effluent total nitrogen (TN) concentration may range from 2.0 to 4.0 g N/m(3) with about 25-50% in the form of organic nitrogen (ON). In this study, current approaches to modeling organic N conversions (separate processes vs. constant contents of organic fractions) were compared. A new conceptual model of ON conversions was developed and combined with Activated Sludge Model No. 2d (ASM2d). The model addresses a new insight into the processes of ammonification, biomass decay and hydrolysis of particulate and colloidal ON (PON and CON, respectively). Three major ON fractions incorporated are defined as dissolved (DON) (<0.1 µm), CON (0.1-1.2 µm) and PON (41.2 µm). Each major fraction was further divided into two sub-fractions - biodegradable and non-biodegradable. Experimental data were collected during field measurements and lab experiments conducted at the ''Wschod'' WWTP (570,000 PE) in Gdansk (Poland). The accurate steady-state predictions of DON and CON profiles were possible by varying ammonification and hydrolysis rates under different electron acceptor conditions. With the same model parameter set, the behaviors of both inorganic N forms (NH4-N, NOX-N) and ON forms (DON, CON) in the batch experiments were predicted. The challenges to accurately simulate and predict effluent ON levels from BNR systems are due to analytical methods of direct ON measurement (replacing TKN) and lack of large enough database (in-process measurements, dynamic variations of the ON concentrations) which can be used to determine parameter value ranges.

  16. Nitrate radicals and biogenic volatile organic compounds: oxidation, mechanisms, and organic aerosol

    NASA Astrophysics Data System (ADS)

    Ng, Nga Lee; Brown, Steven S.; Archibald, Alexander T.; Atlas, Elliot; Cohen, Ronald C.; Crowley, John N.; Day, Douglas A.; Donahue, Neil M.; Fry, Juliane L.; Fuchs, Hendrik; Griffin, Robert J.; Guzman, Marcelo I.; Herrmann, Hartmut; Hodzic, Alma; Iinuma, Yoshiteru; Jimenez, José L.; Kiendler-Scharr, Astrid; Lee, Ben H.; Luecken, Deborah J.; Mao, Jingqiu; McLaren, Robert; Mutzel, Anke; Osthoff, Hans D.; Ouyang, Bin; Picquet-Varrault, Benedicte; Platt, Ulrich; Pye, Havala O. T.; Rudich, Yinon; Schwantes, Rebecca H.; Shiraiwa, Manabu; Stutz, Jochen; Thornton, Joel A.; Tilgner, Andreas; Williams, Brent J.; Zaveri, Rahul A.

    2017-02-01

    Oxidation of biogenic volatile organic compounds (BVOC) by the nitrate radical (NO3) represents one of the important interactions between anthropogenic emissions related to combustion and natural emissions from the biosphere. This interaction has been recognized for more than 3 decades, during which time a large body of research has emerged from laboratory, field, and modeling studies. NO3-BVOC reactions influence air quality, climate and visibility through regional and global budgets for reactive nitrogen (particularly organic nitrates), ozone, and organic aerosol. Despite its long history of research and the significance of this topic in atmospheric chemistry, a number of important uncertainties remain. These include an incomplete understanding of the rates, mechanisms, and organic aerosol yields for NO3-BVOC reactions, lack of constraints on the role of heterogeneous oxidative processes associated with the NO3 radical, the difficulty of characterizing the spatial distributions of BVOC and NO3 within the poorly mixed nocturnal atmosphere, and the challenge of constructing appropriate boundary layer schemes and non-photochemical mechanisms for use in state-of-the-art chemical transport and chemistry-climate models. This review is the result of a workshop of the same title held at the Georgia Institute of Technology in June 2015. The first half of the review summarizes the current literature on NO3-BVOC chemistry, with a particular focus on recent advances in instrumentation and models, and in organic nitrate and secondary organic aerosol (SOA) formation chemistry. Building on this current understanding, the second half of the review outlines impacts of NO3-BVOC chemistry on air quality and climate, and suggests critical research needs to better constrain this interaction to improve the predictive capabilities of atmospheric models.

  17. Nitrate radicals and biogenic volatile organic compounds: oxidation, mechanisms, and organic aerosol

    SciTech Connect

    Ng, Nga Lee; Brown, Steven S.; Archibald, Alexander T.; Atlas, Elliot; Cohen, Ronald C.; Crowley, John N.; Day, Douglas A.; Donahue, Neil M.; Fry, Juliane L.; Fuchs, Hendrik; Griffin, Robert J.; Guzman, Marcelo I.; Herrmann, Hartmut; Hodzic, Alma; Iinuma, Yoshiteru; Jimenez, José L.; Kiendler-Scharr, Astrid; Lee, Ben H.; Luecken, Deborah J.; Mao, Jingqiu; McLaren, Robert; Mutzel, Anke; Osthoff, Hans D.; Ouyang, Bin; Picquet-Varrault, Benedicte; Platt, Ulrich; Pye, Havala O. T.; Rudich, Yinon; Schwantes, Rebecca H.; Shiraiwa, Manabu; Stutz, Jochen; Thornton, Joel A.; Tilgner, Andreas; Williams, Brent J.; Zaveri, Rahul A.

    2017-01-01

    Oxidation of biogenic volatile organic compounds (BVOC) by the nitrate radical (NO3) represents one of the important interactions between anthropogenic emissions related to combustion and natural emissions from the biosphere. This interaction has been recognized for more than 3 decades, during which time a large body of research has emerged from laboratory, field, and modeling studies. NO3-BVOC reactions influence air quality, climate and visibility through regional and global budgets for reactive nitrogen (particularly organic nitrates), ozone, and organic aerosol. Despite its long history of research and the significance of this topic in atmospheric chemistry, a number of important uncertainties remain. These include an incomplete understanding of the rates, mechanisms, and organic aerosol yields for NO3-BVOC reactions, lack of constraints on the role of heterogeneous oxidative processes associated with the NO3 radical, the difficulty of characterizing the spatial distributions of BVOC and NO3 within the poorly mixed nocturnal atmosphere, and the challenge of constructing appropriate boundary layer schemes and non-photochemical mechanisms for use in state-of-the-art chemical transport and chemistry–climate models.

    This review is the result of a workshop of the same title held at the Georgia Institute of Technology in June 2015. The first half of the review summarizes the current literature on NO3-BVOC chemistry, with a particular focus on recent advances in instrumentation and models, and in organic nitrate and secondary organic aerosol (SOA) formation chemistry. Building on this current understanding, the second half of the review outlines impacts of NO3-BVOC chemistry on air quality and climate, and suggests critical research needs to better constrain this interaction to improve the predictive capabilities of atmospheric models.

  18. Bulk and Compound-Specific Stable Nitrogen Isotopes in Plankton Reveal Large Impact of Diazotrophy across the Subtropical North Atlantic

    NASA Astrophysics Data System (ADS)

    Mompean de la Rosa, M.; McCarthy, M.; Bode, A.

    2012-12-01

    Enhanced stratification linked to global warming is predicted to decrease nutrient input from deep waters, and may therefore increase oligotrophy in the subtropical ocean. However, nitrogen fixation in many subtropical regions also supports a significant fraction of primary production, a process likely to be enhanced by the same warm/stratified conditions. The shifting balance between major nutrient sources with global change may alter subtropical food webs, possibly strongly affecting the production and export of organic matter. In this study we examined the spatial variability of stable nitrogen isotopes in plankton size fractions in the upper 200 m in a high spatial resolution transect across the Atlantic (24N) during the Malaspina-2010. Our main goal was to determine the major origin of nitrogen for plankton production. Bulk stable isotopes in all size fractions showed a nearly symmetrical spatial distribution, with the lowest values (σ15N <1‰) in the central zone, and were inversely correlated to the abundance of the nitrogen-fixer Trichodesmium. Diazotrophy was estimated to account for >50% of organic nitrogen in the central zone, however it was also very significant (>30%) in eastern and western zones. The relative nitrogen contribution from diazotrophy also increased with increasing plankton size fraction, suggesting the increasing concentration (importance) of recently fixed nitrogen at higher trophic levels, with potential implication for sources of exported organic N. To further explore a possible linkage with trophic position, we also measured compound-specific σ15N values of amino acids, which allowed us to explicitly calculate average trophic position for different plankton size classes. The σ15N value of Phe was then used as direct molecular-level proxy for σ15N value of primary production across the plankton size spectrum. These results indicate that the zone influenced by diazotrophy in the North Atlantic is much larger than reported in

  19. Mathematical modeling of wastewater-derived biodegradable dissolved organic nitrogen.

    PubMed

    Simsek, Halis

    2016-11-01

    Wastewater-derived dissolved organic nitrogen (DON) typically constitutes the majority of total dissolved nitrogen (TDN) discharged to surface waters from advanced wastewater treatment plants (WWTPs). When considering the stringent regulations on nitrogen discharge limits in sensitive receiving waters, DON becomes problematic and needs to be reduced. Biodegradable DON (BDON) is a portion of DON that is biologically degradable by bacteria when the optimum environmental conditions are met. BDON in a two-stage trickling filter WWTP was estimated using artificial intelligence techniques, such as adaptive neuro-fuzzy inference systems, multilayer perceptron, radial basis neural networks (RBNN), and generalized regression neural networks. Nitrite, nitrate, ammonium, TDN, and DON data were used as input neurons. Wastewater samples were collected from four different locations in the plant. Model performances were evaluated using root mean square error, mean absolute error, mean bias error, and coefficient of determination statistics. Modeling results showed that the R(2) values were higher than 0.85 in all four models for all wastewater samples, except only R(2) in the final effluent sample for RBNN modeling was low (0.52). Overall, it was found that all four computing techniques could be employed successfully to predict BDON.

  20. Enantiomeric and Isotopic Analysis of Organic Compounds in Carbonaceous Meteorites

    NASA Technical Reports Server (NTRS)

    Cooper, George

    2004-01-01

    Carbonaceous meteorites are relatively enriched in soluble organic compounds. The Murchison and Murray meteorites contain numerous compounds of interest in the study of early solar system organic chemistry and organic compounds of potential importance for the origin of life. These include: amino acids, amides, carboxylic acids, and polyols. This talk will focus on the enantiomeric and isotopic analysis of individual meteoritic compounds - primarily polyol acids. The analyses will determine if, in addition to certain amino acids from Murchison, another potentially important class of prebiotic compounds also contains enantiomeric excesses, i.e., excesses that could have contributed to the current homochirality of life. Preliminary enantiomeric and isotopic (C- 13) measurements of Murchison glyceric acid show that it is indeed extraterrestrial. C-13 and D isotope analysis of meteoritic sugar alcohols (glycerol, threitol, ribitol, etc.) has shown that they are also indigenous to the meteorite.

  1. Organics and nitrogen removal from textile auxiliaries wastewater with A2O-MBR in a pilot-scale.

    PubMed

    Sun, Faqian; Sun, Bin; Hu, Jian; He, Yangyang; Wu, Weixiang

    2015-04-09

    The removal of organic compounds and nitrogen in an anaerobic-anoxic-aerobic membrane bioreactor process (A(2)O-MBR) for treatment of textile auxiliaries (TA) wastewater was investigated. The results show that the average effluent concentrations of chemical oxygen demand (COD), ammonium nitrogen (NH4(+)-N) and total nitrogen (TN) were about 119, 3 and 48 mg/L under an internal recycle ratio of 1.5. The average removal efficiency of COD, NH4(+)-N and TN were 87%, 96% and 55%, respectively. Gas chromatograph-mass spectrometer analysis indicated that, although as much as 121 different types of organic compounds were present in the TA wastewater, only 20 kinds of refractory organic compounds were found in the MBR effluent, which could be used as indicators of effluents from this kind of industrial wastewater. Scanning electron microscopy analysis revealed that bacterial foulants were significant contributors to membrane fouling. An examination of foulants components by wavelength dispersive X-ray fluorescence showed that the combination of organic foulants and inorganic compounds enhanced the formation of gel layer and thus caused membrane fouling. The results will provide valuable information for optimizing the design and operation of wastewater treatment system in the textile industry.

  2. Removal of nitrogen compounds from landfill leachate using reverse osmosis with leachate stabilization in a buffer tank.

    PubMed

    Talalaj, Izabela Anna

    2015-01-01

    In this paper, a removal of nitrogen compounds from a landfill leachate during reverse osmosis (RO) was evaluated. The treatment facility consists of a buffer tank and a RO system. The removal rate of N─NH4, [Formula: see text] and [Formula: see text] in the buffer tank reached 14%, 91% and 41%, respectively. The relatively low concentration of organic carbon limits N─NH4 oxidation in the buffer tank. The removal rate for the total organic nitrogen (TON) was 47%. The removal rate in RO was 99% for [Formula: see text], 84.1% for [Formula: see text] and 41% for [Formula: see text]. The accumulation of [Formula: see text] may be the result of a low pH, which before the RO process is reduced to a value of 6.0-6.5. Besides it, the cause for a low removal rate of the [Formula: see text] in the buffer tank and during RO may be free ammonia, which can inhibit the [Formula: see text] oxidation. The removal rates of total inorganic nitrogen and TON in the RO treatment facility were similar being 99% and 98.5%, respectively.

  3. The effect of formaldehyde and nitrogen-containing compounds on the size and volume of aerosol particles

    NASA Astrophysics Data System (ADS)

    Millage, K.; Galloway, M. M.; De Haan, D. O.

    2012-12-01

    Atmospheric aerosol can interact with clouds in many ways, often resulting in the redistribution or absorption of solar energy or changes in precipitation efficiency. Secondary organic aerosol (SOA) in particular has been linked to climate change and a reduction in the number and size of cloud particles. The reactions of nitrogen containing compounds (primary amines, amino acids and ammonium sulfate) with carbonyl compounds (such as formaldehyde and glycolaldehyde) are potential sources of SOA. Aerosol containing formaldehyde and nitrogen-containing compounds (glycine, methylamine, arginine, or ammonium sulfate) was generated from buffered solutions (pH 5.4) using a nebulizer. The aerosol was then equilibrated into a chamber containing humid air (82-84% RH), and particle sizes were measured using a SMPS system over a period of 1 hour in order to examine how the size and volume of the aerosol particles changed. Formaldehyde concentrations were varied over multiple experiments. Arginine displayed a trend of increasing relative particle size with increasing formaldehyde concentration. Ammonium sulfate and formaldehyde displayed a decrease in relative particle sizes from 0:1 to 2:1 ratios of formaldehyde to ammonium sulfate, but then an increase in relative particle sizes with increasing amounts of formaldehyde. Similarly, glycine and methylamine initially displayed decreasing relative particle sizes, until reaching a 1:1 ratio of each to formaldehyde at which point the relative particle sizes steadily increased. These effects were likely caused by the evaporation of first-generation imine products.

  4. [Effect of nitrogen-containing compounds on hydrogen light emission and nitrogen fixation by purple bacteria].

    PubMed

    Kondrat'eva, E N; Gogotov, I N; Gruzinskiĭ, I V

    1979-01-01

    The cells of Rhodospirillum rubrum and Thiocapsa roseopersicina grown in media containing glutamate and arginine, respectively, as well as under conditions of nitrogen fixation evolve H2 in the light. If the cultures were grown in media with NH4+, NO3-, urea, glutamine or asparagine, hydrogen photoevolution by the cells and acetylene reduction started after the lag-phase and proceeded at a low rate. Extracts of such cells did not display the activity of nitrogenase which could be assayed by the ATP-dependent evolution of H2 from dithionite. The data obtained confirm the fact that hydrogen photoevolution by purple bacteria involves nitrogenase whose synthesis is regulated (according to the action of glutamine) with the participation of glutamine synthetase. NH4+, glutamine and asparagine inhibit also hydrogen photoproduction by purple bacteria and acetylene photoreduction. However, they have no effect on hydrogen evolution in the dark by the cells of R. rubrum and T. roseopersicina in the presence of formiate or pyruvate, respectively, whereas carbon monoxide inhibits hydrogen production. Therefore, hydrogen production by purple bacteria in the dark must be catalyzed by hydrogenase.

  5. SYNTHESIZING ORGANIC COMPOUNDS USING LIGHT-ACTIVATED TIO2

    EPA Science Inventory

    High-value organic compounds have been synthesized successfully from linear and cyclic hydrocarbons, by photocatalytic oxidation using a semiconductor material, titanium dioxide (TiO2). Various hydrocarbons were partially oxgenated in both liquid and gaseous phase reactors usi...

  6. ESTIMATION OF PHYSIOCHEMICAL PROPERTIES OF ORGANIC COMPOUNDS BY SPARC

    EPA Science Inventory

    The computer program SPARC (SPARC Performs Automated Reasoning in Chemistry) has been under development for several years to estimate physical properties and chemical reactivity parameters of organic compounds strictly from molecular structure. SPARC uses computational algorithms...

  7. SEPARATION OF VOLATILE ORGANIC COMPOUNDS FROM SURFACTANT SOLUTIONS BY PERVAPORATION

    EPA Science Inventory

    Pervaporation is gradually becoming an accepted and practical method for the recovery of volatile organic compounds (VOCs) from aqueous process and waste streams. As the technolog has matured, new applications for pervaporation have emerged. One such application is the separati...

  8. Synthesis of fluorinated organic compounds using oxygen difluoride

    NASA Technical Reports Server (NTRS)

    Toy, M. S.

    1971-01-01

    Oxygen difluoride synthesis is a much simpler, higher-yield procedure than reactions originally followed to synthesize various fluorinated organic compounds. Extreme care is taken in working with oxygen difluoride as its reactions present severe explosion hazard.

  9. INDOOR AIR QUALITY DATA BASE FOR ORGANIC COMPOUNDS

    EPA Science Inventory

    The report gives results of the compilation of a data base for concentrations of organic compounds measured indoors. ased on a review of the literature from 1979 through 1990, the data base contains information on over 220 compounds ranging in molecular weight from 30 to 446. he ...

  10. VOLATILE ORGANIC COMPOUNDS MEASURED IN DEARS PASSIVE SAMPLERS

    EPA Science Inventory

    A suite of 27 volatile organic compounds (VOCs) were monitored in personal exposures, indoors and outdoors of participant's residences, and at a central community site during the DEARS summer 2004 monitoring season. The list of VOCs focused on compounds typically associated with ...

  11. Speciation of volatile organic compounds from poultry production

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The air consent agreement between EPA and large animal feeding operations (AFO) is designed to determine at what level compounds are being emitted from these facilities. However, the methodology used for quantifying total non-methane hydrocarbons and speciation of volatile organic compounds (VOC) n...

  12. Predicting the emission of volatile organic compounds from silage systems

    Technology Transfer Automated Retrieval System (TEKTRAN)

    As a precursor to smog, emission of volatile organic compounds (VOCs) to the atmosphere is an environmental concern in some regions. The major VOC emission source from farms is silage, with emissions coming from the silo face, mixing wagon, and feed bunk. The major compounds emitted are alcohols wit...

  13. Molecular and Enantiomeric Analysis of Organic Compounds in Carbonaceous Meteorites

    NASA Technical Reports Server (NTRS)

    Cooper, George

    2003-01-01

    Carbonaceous meteorites are relatively enriched in carbon. Much of this carbon is in the form of soluble organic compounds. The Murchison and Murray meteorites are the best-characterized carbonaceous meteorites with respect to organic chemistry. Their content of organic compounds has led to an initial understanding of early solar system organic chemistry as well as what compounds may have played a role in the origin of life (Cronin and Chang, 1993). Reported compounds include: amino acids, amides, carboxylic acids, sulfonic acids, and polyols. This talk will focus on the molecular and enantiomeric analysis of individual meteoritic compounds: polyol acids; and a newly identified class of meteorite compounds, keto acids, i.e., acetoacetic acid, levulinic acid, etc. Keto acids (including pyruvic) are critically important in all contemporary organisms. They are key intermediates in metabolism and processes such as the citric acid cycle. Using gas chromatography-mass spectrometry we identified individual meteoritic keto acids after derivatization to one or more of the following forms: isopropyl ester (ISP), trimethyIsiIy1 (TMS), tert-butyldimethylsilyl (BDMS). Ongoing analyses will determine if, in addition to certain amino acids from Murchison (Cronin and Pizzarello, 1997), other potentially important prebiotic compounds also contain enantiomeric excesses, i.e., excesses that could have contributed to the current homochirality of life.

  14. Shock Modifications of Organic Compounds in Carbonaceous Chondrite Parent Bodies

    NASA Technical Reports Server (NTRS)

    Cooper, George W.

    1998-01-01

    Impacts among asteroidal objects would have altered or destroyed pre-existing organic matter in both targets and projectiles to a greater or lesser degree depending upon impact velocities. To begin filling a knowledge gap on the shock metamorphism of organic compounds, we are studying the effects of shock impacts on selected classes of organic compounds utilizing laboratory shock facilities. Our approach is to subject mixtures of organic compounds, embedded in the matrix of the Murchison meteorite, to simulated hypervelocity impacts by firing them into targets at various pressures. The mixtures are then analyzed to determine the amount of each compound that survives as well as to determine if new compounds are being synthesized. The initial compounds added to the matrix (with the exception of thiosulfate). The sulfonic acids were chosen in part because they are relatively abundant in Murchison, relatively stable, and because they and the phosphonic acids are the first well-characterized homologous series of organic sulfur and phosphorus compounds identified in an extraterrestrial material. Experimental procedures were more fully described in the original proposal. A 20 mm gun, with its barrel extending into a vacuum chamber (10(exp -2) torr), was used to launch the projectile containing the sample at approx. 1.6 km/sec (3,600 mi/hr) into the target material. Maximum pressure of impact depend on target/projectile materials. The target was sufficiently thin to assure minimum pressure decay over the total sample thickness.

  15. Process for preparing a chemical compound enriched in isotope content. [nitrogen 15-enriched nitric acid

    DOEpatents

    Michaels, E.D.

    1981-02-25

    A process to prepare a chemical enriched in isotope content includes: a chemical exchange reaction between a first and second compound which yields an isotopically enriched first compound and an isotopically depleted second compound; the removal of a portion of the first compound as product and the removal of a portion of the second compound as spent material; the conversion of the remainder of the first compound to the second compound for reflux at the product end of the chemical exchange reaction region; the conversion of the remainder of the second compound to the first compound for reflux at the spent material end of the chemical exchange region; and the cycling of the additional chemicals produced by one conversion reaction to the other conversion reaction, for consumption therein. One of the conversion reactions is an oxidation reaction, and the energy that it yields is used to drive the other conversion reaction, a reduction. The reduction reaction is carried out in a solid polymer electrolyte electrolytic reactor. The overall process is energy efficient and yields no waste by-products. A particular embodiment of the process in the production of nitrogen-15-enriched nitric acid.

  16. Process for reducing organic compounds with calcium, amine, and alcohol

    DOEpatents

    Benkeser, Robert A.; Laugal, James A.; Rappa, Angela

    1985-01-01

    Olefins are produced by contacting an organic compound having at least one benzene ring with calcium metal, ethylenediamine, a low molecular weight aliphatic alcohol, and optionally a low molecular weight aliphatic primary amine, and/or an inert, abrasive particulate substance. The reduction is conducted at temperatures ranging from about -10.degree. C. to about 30.degree. C. or somewhat higher. Substantially all of the organic compounds are converted to corresponding cyclic olefins, primarily diolefins.

  17. Process for reducing organic compounds with calcium, amine, and alcohol

    DOEpatents

    Benkeser, R.A.; Laugal, J.A.; Rappa, A.

    1985-08-06

    Olefins are produced by contacting an organic compound having at least one benzene ring with calcium metal, ethylenediamine, a low molecular weight aliphatic alcohol, and optionally a low molecular weight aliphatic primary amine, and/or an inert, abrasive particulate substance. The reduction is conducted at temperatures ranging from about [minus]10 C to about 30 C or somewhat higher. Substantially all of the organic compounds are converted to corresponding cyclic olefins, primarily diolefins.

  18. The degradation of dissolved organic nitrogen associated with melanoidin using a UV/H2O2 AOP.

    PubMed

    Dwyer, Jason; Kavanagh, Lydia; Lant, Paul

    2008-04-01

    The aim of this study was to examine the simultaneous degradation of dissolved organic nitrogen (DON) and associated colour from wastewater containing melanoidins by an advanced oxidation process (AOP). UV irradiation of H2O2 was used as the mechanism to create the hydroxyl radical for oxidation. Melanoidins are large nitrogenous organic compounds that are refractory during biological wastewater treatment processes. The simultaneous degradation of DON and colour, present as a result of these compounds, was investigated using an AOP. The oxidation process was much more capable of removing colour (99% degradation), dissolved organic carbon (DOC) (50% degradation) and DON (25% degradation) at the optimal applied dose of hydrogen peroxide for the system (3300 mg l(-1)). This indicated that colour and DON removal were decoupled problems for the purpose of treating melanoidin by an AOP and thus colour removal can not be used as an indication of DON removal Colour was caused by organic molecules with molecular weight greater than 10 kDa. Oxidation caused a partial reduction of the DON (41-15% of the total dissolved nitrogen) and DOC (29-14% of the DOC) associated with the large molecular weight fraction (>10 kDa) and almost complete colour removal (87-3% of the total colour). The degraded DON was mostly accounted for by the formation of ammonia (31% of the nitrogen removed from the large fraction) and small molecular weight compounds (66% of the nitrogen removed from the large fraction). The degraded DOC appeared to be mostly mineralised (to CO2) with only 20% of the degraded compounds appearing as small molecular weight DOC.

  19. Dominance of organic nitrogen from headwater streams to large rivers across the conterminous United States

    USGS Publications Warehouse

    Scott, D.; Harvey, J.; Alexander, R.; Schwarz, G.

    2007-01-01

    The frequency and magnitude of hypoxic areas in coastal waterbodies are increasing across the globe, partially in response to the increase in nitrogen delivery from the landscape (Diaz, 2001; Rabalais et al., 2002). Although studies of annual total nitrogen and nitrate yields have greatly improved understanding of the contaminant sources that contribute to riverine nitrogen loads (Alexander et al., 2000; Caraco and Cole, 1999), the emphasis of these studies on annual timescales and selected nitrogen forms is not sufficient to understand the factors that control the cycling, transport, and fate of reactive nitrogen. Here we use data from 850 river stations to calculate long-term mean-annual and interannual loads of organic, ammonia, and nitrate-nitrite nitrogen suitable for spatial analysis. We find that organic nitrogen is the dominant nitrogen pool within rivers across most of the United States and is significant even in basins with high anthropogenic sources of nitrogen. Downstream organic nitrogen patterns illustrate that organic nitrogen is an abundant fraction of the nitrogen loads in all regions. Although the longitudinal patterns are not consistent across regions, these patterns are suggestive of cycling between ON and NO3- on seasonal timescales influenced by land use, stream morphology, and riparian connectivity with active floodplains. Future regional studies need to incorporate multinitrogen species at intraannual timescales, as well as stream characteristics beyond channel depth, to elucidate the roles of nitrogen sources and in-stream transformations on the fate and reactivity of riverine nitrogen transported to coastal seas.

  20. Investigation of Organic Compound Reactivity in Liquid and Frozen Aqueous Systems Using Relative Rate Experiments

    NASA Astrophysics Data System (ADS)

    Kurek, L.; Grannas, A. M.

    2012-12-01

    Previous studies have shown that snow and ice are highly reactive media where photochemical reactions occur. These reactions can have important consequences for the environment, including the production of organic compounds, halogens and nitrogen oxides that impact surface boundary layer chemistry. Laboratory-based studies have shown that the nature of the sample and the physical location of solutes play a large role in determining the reactivity of a particular compound. During the freezing of aqueous solutions, most solute molecules become excluded from the ice crystal lattice, increasing their apparent concentrations as they accumulate in liquid-like layers, micropockets, and microveins within the ice (freeze-concentration effect). In an effort to better understand how the physicochemical properties of solutes may impact reactivity in frozen solutions, we have examined the relative reaction rates of various organic compounds with hydroxyl radical in both liquid and frozen conditions. Solutions containing two target organic compounds and hydrogen peroxide were made in liquid and frozen phases, and then irradiated using a Q-Panel 340 lamp to simulate natural sunlight. Relative rates of reaction were then obtained for the two compounds in both liquid and ice conditions. In most cases the reactions proceeded more quickly in liquid samples, and the relative rates of reaction were different in liquid and frozen conditions. We will discuss the potential role of a compound's physicochemical properties and the influence of the physical nature of the sample with respect to observed reactivity differences.

  1. Mineral and organic compounds in leachate from landfill with concentrate recirculation.

    PubMed

    Talalaj, Izabela Anna

    2015-02-01

    The effect of a reverse osmosis concentrate recirculation on the mineral and organic compounds in a landfill leachate was investigated. Investigated was the quality of a leachate from two landfills operated for different periods (a 20-year-old Cell A and a 1-year-old Cell B), where the concentrate was recirculated. Examined were general parameters (conductivity, pH), organic compounds (biochemical oxygen demand (BOD), chemical oxygen demand (COD), total organic nitrogen, BOD/COD), and inorganic compounds (nitrogen ammonia, sulfite, sulfate, cyanide, boron, chloride, ferrous, zinc, chrome, copper). The findings from the first year of investigation showed that over the initial period of recirculation, the concentration of organic compounds (BOD, COD) increased, but after 6 months their values stabilized. It indicates that the concentrate recirculation accelerated organic decomposition, especially in the new landfill Cell. The analysis of inorganic parameters showed that recirculation landfills produce a leachate with a higher concentration of N-NH4, and Cl(-). In case of the old landfill Cell, an increase in B and Fe was also noticeable. These compounds are cyclically washed out from a waste dump and require an additional pretreatment in order to exclude them from recirculation cycle. The increased concentration of Cu, Zn, and Fe was noticed during the initial months of recirculation and in the season of intense atmospheric precipitation in the leachate from both Cells. Higher values of electro conductivity, Cl(-), N-NH4 (+), B, and Fe in the leachate from the old field indicate that the attenuation capacity of this landfill is close to exhaustion.

  2. Bonded-phase extraction column isolation of organic compounds in groundwater at a hazardous waste site

    SciTech Connect

    Rostad, C.E.; Pereira, W.E.; Ratcliff, S.M.

    1984-12-01

    A procedure for isolation of hazardous organic compounds from water for gas chromatography/mass spectrometry analysis is presented and applied to creosote- and pentachlorophenol-contaminated groundwater resulting from wood-treatment processes. This simple procedure involved passing a 50-100 mL sample through a bonded-phase extraction column, eluting the trapped organic compounds from the column with 2-4 mL of solvent, and evaporating the sample to 100 micro-L with a stream of dry nitrogen, after which the sample was ready for gas chromatography/mass spectrometry analysis. Representative compounds indicative of creosote contamination were used for recovery and precision studies from the cyclohexyl-bonded phase. Recovery of these compounds from n-octyl-, n-octadecyl-, cyclohexyl-, and phenyl-bonded phases was compared. The bonded phase that exhibited the best recovery and least bias toward acidic or basic compounds was the n-octadecyl phase. Detailed compound identification is given for compounds isolated from creosote- and pentrachlorophenol-contaminated groundwater using the cyclohexyl-bonded phase. 12 references, 1 figure, 4 tables.

  3. Transport, behavior, and fate of volatile organic compounds in streams

    USGS Publications Warehouse

    Rathbun, R.E.

    1998-01-01

    Volatile organic compounds (VOCs) are compounds with chemical and physical properties that allow the compounds to move freely between the water and air phases of the environment. VOCs are widespread in the environment because of this mobility. Many VOCs have properties making them suspected or known hazards to the health of humans and aquatic organisms. Consequently, understanding the processes affecting the concentration and distribution VOCs in the environment is necessary. The U.S. Geological Survey selected 55 VOCs for study. This report reviews the characteristics of the various process that could affect the transport, behavior, and fate of these VOCs in streams.

  4. Automated solid-phase synthesis of linear nitrogen-linked compounds.

    PubMed

    Davis, P W; Swayze, E E

    2000-01-01

    A synthetic library motif has been developed to create linear, nitrogen-linked compounds as screening libraries to target structured RNA for drug discovery. Scaffolds were created in situ from suitably protected bifunctional compounds linked together either by acyl or amine links. Acyl links were created from amino acids, which also introduce one degree of functionality. Amine links from the amino acid nitrogen were created from an N-protected amino alcohol via Fukuyama Mitsunobu alkylation. Each amine site can then be used for introducing functionality or extending the scaffold. This synthetic scheme can be used to create a wide variety of modified-backbone PNA in situ, as shown by the synthesis of a PNA-type monomer. The synthesis steps have been enabled on a 96-well parallel-array synthesizer for high-throughput synthesis. The present study represents a versatile synthetic approach to a wide variety of potential RNA-binding molecules.

  5. Composition of Organic Compounds Adsorbed on PM10 in the Air Above Maribor.

    PubMed

    Miuc, Alen; Vončina, Ernest; Lečnik, Uroš

    2015-01-01

    Organic compounds in atmospheric particulate matterabove Maribor were analysed in 120 samples of PM10 sampled according to the EN 12341:2014 reference method. Organic compounds compositions were investigated together with the primary and secondary sources of air pollution. Silylation as derivatisation method was used for the GC/MS determination of volatile and semi-volatile polar organic compounds. Distribution of fatty acids, n-alkanes and iso-alkanes, phthalate esters, siloxanes, different sterols, various sugars and sugar alcohols, compounds of lignin and resin acids, dicarboxylic acids from photochemical reactions, PAHs, organic nitrogen compounds and products from secondary oxidation of monoterpenes were determined. The use of silicone grease for the purpose of lubricating the impact surface of the air sampler caused higher values of gravimetric determination. Solid particles may have been bounced from the surface of a greasy impact plate and re-entrained within the air stream and then collected on a sample filter. The carryover of siloxanes was at least from 5% up to 15% of the accumulated particles weight, depending on ambient temperature. This was the reason that the gravimetric results for determination of PM10 according to the standard EN 12341:2014 were overestimated.

  6. Analysis of volatile organic compounds from illicit cocaine samples

    SciTech Connect

    Robins, W.H.; Wright, B.W.

    1994-07-01

    Detection of illicit cocaine hydrochloride shipments can be improved if there is a greater understanding of the identity and quantity of volatile compounds present. This study provides preliminary data concerning the volatile organic compounds detected in a limited Set of cocaine hydrochloride samples. In all cases, cocaine was one of the major volatile compounds detected. Other tropeines were detected in almost all samples. Low concentrations of compounds that may be residues of processing solvents were observed in some samples. The equilibrium emissivity of. cocaine from cocaine hydrochloride was investigated and a value of 83 parts-per-trillion was determined.

  7. Rejection of trace organic compounds by high-pressure membranes.

    PubMed

    Kim, T U; Amy, G; Drewes, J E

    2005-01-01

    High-pressure membranes, encompassing reverse osmosis (RO), nanofiltration (NF), and low-pressure RO, may provide an effective treatment barrier for trace organic compounds including disinfection by-products (DBPs), pesticides, solvents, endocrine disrupting compounds (EDCs) and pharmaceutically active compounds (PhACs). The objective is to develop a mechanistic understanding of the rejection of trace organic compounds by high-pressure membranes, based on an integrated framework of compound properties, membrane properties, and operational conditions. Eight trace organic compounds, four DBPs and four chlorinated (halogenated) solvents, are being emphasized during an initial study, based on considerations of compound properties, occurrence, and health effects (regulations). Four polyamide FilmTec membranes; three reverse osmosis/RO (BW-400, LE-440, XLE-440) and one nanofiltration/NF (NF-90); are being characterized according to pure water permeability (PWP), molecular weight cutoff (MWCO), hydrophobicity (contact angle), and surface charge (zeta potential). It is noteworthy that rejections of compounds of intermediate hydrophobicity by the candidate membranes were observed to be less than salt rejections reported for these membranes, suggesting that transport of these solutes through these membranes is facilitated by solute-membrane interactions. We are continuing with diffusion cell measurements to describe solute-membrane interactions by estimation of diffusion coefficients through membranes pores, either hindered or facilitated.

  8. Key intermediates in nitrogen transformation during microwave pyrolysis of sewage sludge: a protein model compound study.

    PubMed

    Zhang, Jun; Tian, Yu; Cui, Yanni; Zuo, Wei; Tan, Tao

    2013-03-01

    The nitrogen transformations with attention to NH3 and HCN were investigated at temperatures of 300-800°C during microwave pyrolysis of a protein model compound. The evolution of nitrogenated compounds in the char, tar and gas products were conducted. The amine-N, heterocyclic-N and nitrile-N compounds were identified as three important intermediates during the pyrolysis. NH3 and HCN were formed with comparable activation energies competed to consume the same reactive substances at temperatures of 300-800°C. The deamination and dehydrogenation of amine-N compounds from protein cracking contributed to the formation of NH3 (about 8.9% of Soy-N) and HCN (6.6%) from 300 to 500°C. The cracking of nitrile-N and heterocyclic-N compounds from the dehydrogenation and polymerization of amine-N generated HCN (13.4%) and NH3 (31.3%) between 500 and 800°C. It might be able to reduce the HCN and NH3 emissions through controlling the intermediates production at temperatures of 500-800°C.

  9. Nitrogen oxides as dopants for the detection of aromatic compounds with ion mobility spectrometry.

    PubMed

    Gaik, Urszula; Sillanpää, Mika; Witkiewicz, Zygfryd; Puton, Jarosław

    2017-03-03

    Limits of detection (LODs) in ion mobility spectrometry (IMS) strictly depend on ionization of the analyte. Especially challenging is ionization of compounds with relatively low proton affinity (PA) such as aromatic compounds. To change the course of ion-molecule reactions and enhance the performance of the IMS spectrometer, substances called dopants are introduced into the carrier gas. In this work, we present the results of studies of detection using nitrogen oxides (NOx) dopants. Three aromatic compounds, benzene, toluene, toluene diisocyanate and, for comparison, two compounds with high PA, dimethyl methylphosphonate (DMMP) and triethyl phosphate (TEP), were selected as analytes. The influence of water vapour on these analyses was also studied. Experiments were carried out with a generator of gas mixtures that allowed for the simultaneous introduction of three substances into the carrier gas. The experiments showed that the use of NOx dopants significantly decreases LODs for aromatic compounds and does not affect the detection of compounds with high PA. The water vapour significantly disturbs the detection of aromatic compounds; however, doping with NOx allows to reduce the effect of humidity. Graphical Abstract Two possible ionization mechanisms of aromatic compounds in ion mobility spectrometry: proton transfer reaction and adduct formation.

  10. Recent advances in trifluoromethylation of organic compounds using Umemoto's reagents.

    PubMed

    Zhang, Cai

    2014-09-14

    The incorporation of fluorine-containing moieties into organic compounds is of great importance in pharmaceutical, agricultural, and materials science. Within these organofluorides, the trifluoromethyl group is one of the most important motifs. In recent years, the trifluoromethyl group has attracted more and more attention, and many trifluoromethylated compounds have been found to possess special activities. However, until now, only a few methods have been developed to achieve this efficiently using Umemoto's reagents. This review highlights recent developments in the direct introduction of a trifluoromethyl group into organic compounds with Umemoto's reagents. Seven approaches to the trifluoromethylation of organic compounds are summarized: (i) trifluoromethylation of arenes, (ii) trifluoromethylation of alkenes, (iii) trifluoromethylation of terminal alkynes, (iv) deoxygenative trifluoromethylation of benzylic xanthates, (v) trifluoromethylation of ketoesters, (vi) trifluoromethylation of aryl boronic acids and aromatic amines (synthesis of ArCF3) and (vii) trifluoromethylation of biphenyl isocyanide derivatives.

  11. Characterization of the nitrogen compounds released during yeast autolysis in a model wine system.

    PubMed

    Martínez-Rodríguez, A J; Polo, M C

    2000-04-01

    The nitrogen composition of wines aged with yeast for a long period of time, as in the case of sparkling wines, depends on the composition of the base wine and on the compounds released by the yeast. In this paper, the release of the different classes of nitrogen compounds during autolysis of one of the strains of yeast used in the manufacture of sparkling wines has been studied. The yeast, Saccharomyces bayanus, was suspended in a model wine buffer, pH 3.0 and 10% ethanol, and incubated at 30 degrees C. Samples of the autolysate were taken after 4, 24, 48, 72, 168, and 360 h of autolysis. An electrophoretic and chromatographic study was conducted of the proteins, peptides with molecular weights higher and lower than 700 Da, and amino acids released during the autolysis. Using SDS-PAGE, it was observed that it was predominantly polypeptides with molecular weights lower than 10 000 that were released. Through HPLC of the fraction lower than 10 000 Da, it was observed that it is polypeptides with molecular weights of between 10 000 and 700 Da that are released first and that these later break up to give rise to peptides with molecular weights lower than 700 Da, which in turn break down into amino acids. This indicates that the nature of the nitrogen compounds present in wines aged with yeast depends on the aging time, being less polymerized as the aging time increases.

  12. Molecular nitrogen in natural gas accumulations: Generation from sedimentary organic matter at high temperatures

    SciTech Connect

    Littke, R.; Krooss, B.; Frielingsdorf, J.; Idiz, E.

    1995-03-01

    The occurrence of natural gas accumulations with high percentages (up to 100%) of molecular nitrogen in various hydrocarbon provinces represents a largely unresolved problem and a serious exploration risk. In this context, a geochemical and basin modeling study was performed to evaluate the potential of sedimentary organic matter to generate molecular nitrogen. The masses of nitrogen present in coals - if converted into molecular nitrogen - are sufficient to fill commercial gas reservoirs. A calculation for gas accumulations in northern Germany, where percentages of molecular nitrogen range from less than 5 to greater than 90%, reveals that the molecular nitrogen generated in underlying coal-bearing strata is sufficient to account for the nitrogen gas even in the largest fields. In addition, much of the total nitrogen in clay-rich rock types, such as shales and mudstones, is fixed in sedimentary organic matter and may add to the nitrogen generation capacity of the coals.

  13. Predicting crystal structures of organic compounds.

    PubMed

    Price, Sarah L

    2014-04-07

    Currently, organic crystal structure prediction (CSP) methods are based on searching for the most thermodynamically stable crystal structure, making various approximations in evaluating the crystal energy. The most stable (global minimum) structure provides a prediction of an experimental crystal structure. However, depending on the specific molecule, there may be other structures which are very close in energy. In this case, the other structures on the crystal energy landscape may be polymorphs, components of static or dynamic disorder in observed structures, or there may be no route to nucleating and growing these structures. A major reason for performing CSP studies is as a complement to solid form screening to see which alternative packings to the known polymorphs are thermodynamically feasible.

  14. Scaffold of Asymmetric Organic Compounds - Magnetite Plaquettes

    NASA Technical Reports Server (NTRS)

    Chan, Q. H. S.; Zolensky, M. E.; Martinez, J.

    2015-01-01

    Life on Earth shows preference towards the set of organics with particular spatial configurations, this 'selectivity' is a crucial criterion for life. With only rare exceptions, life prefers the left- (L-) form over the right- (D-) form of amino acids, resulting in an L-enantiomeric excess (L-ee). Recent studies have shown Lee for alpha-methyl amino acids in some chondrites. Since these amino acids have limited terrestrial occurrence, the origin of their stereoselectivity is nonbiological, and it seems appropriate to conclude that chiral asymmetry, the molecular characteristic that is common to all terrestrial life form, has an abiotic origin. A possible abiotic mechanism that can produce chiral asymmetry in meteoritic amino acids is their formation with the presence of asymmetric catalysts, as mineral crystallization can produce spatially asymmetric structures. Magnetite is shown to be an effective catalyst for the formation of amino acids that are commonly found in chondrites. Magnetite 'plaquettes' (or 'platelets'), first described by Jedwab, show an interesting morphology of barrel-shaped stacks of magnetite disks with an apparent dislocation-induced spiral growth that seem to be connected at the center. A recent study by Singh et al. has shown that magnetites can self-assemble into helical superstructures. Such molecular asymmetry could be inherited by adsorbed organic molecules. In order to understand the distribution of 'spiral' magnetites in different meteorite classes, as well as to investigate their apparent spiral configurations and possible correlation to molecular asymmetry, we observed polished sections of carbonaceous chondrites (CC) using scanning electron microscope (SEM) imaging. The sections were also studied by electron backscattered diffraction (EBSD) in order to reconstruct the crystal orientation along the stack of magnetite disks.

  15. Organic nitrogen uptake is a significant contributor to nitrogen economy of subtropical epiphytic bryophytes.

    PubMed

    Song, Liang; Lu, Hua-Zheng; Xu, Xing-Liang; Li, Su; Shi, Xian-Meng; Chen, Xi; Wu, Yi; Huang, Jun-Biao; Chen, Quan; Liu, Shuai; Wu, Chuan-Sheng; Liu, Wen-Yao

    2016-07-27

    Without any root contact with the soil, epiphytic bryophytes must experience and explore poor, patchy, and heterogeneous habitats; while, the nitrogen (N) uptake and use strategies of these organisms remain uncharacterized, which obscures their roles in the N cycle. To investigate the N sources, N preferences, and responses to enhanced N deposition in epiphytic bryophytes, we carried out an in situ manipulation experiment via the (15)N labelling technique in an Asian cloud forest. Epiphytic bryophytes obtained more N from air deposition than from the bark, but the contribution of N from the bark was non-negligible. Glycine accounted for 28.4% to 44.5% of the total N in bryophyte tissue, which implies that organic N might serve as an important N source. Increased N deposition increased the total N uptake, but did not alter the N preference of the epiphytic bryophytes. This study provides sound evidence that epiphytic bryophytes could take up N from the bark and wet deposition in both organic and inorganic N forms. It is thus important to consider organic N and bark N sources, which were usually neglected, when estimating the role of epiphytic bryophytes in N cycling and the impacts of N deposition on epiphytic bryophytes in cloud forests.

  16. Organic nitrogen uptake is a significant contributor to nitrogen economy of subtropical epiphytic bryophytes

    NASA Astrophysics Data System (ADS)

    Song, Liang; Lu, Hua-Zheng; Xu, Xing-Liang; Li, Su; Shi, Xian-Meng; Chen, Xi; Wu, Yi; Huang, Jun-Biao; Chen, Quan; Liu, Shuai; Wu, Chuan-Sheng; Liu, Wen-Yao

    2016-07-01

    Without any root contact with the soil, epiphytic bryophytes must experience and explore poor, patchy, and heterogeneous habitats; while, the nitrogen (N) uptake and use strategies of these organisms remain uncharacterized, which obscures their roles in the N cycle. To investigate the N sources, N preferences, and responses to enhanced N deposition in epiphytic bryophytes, we carried out an in situ manipulation experiment via the 15N labelling technique in an Asian cloud forest. Epiphytic bryophytes obtained more N from air deposition than from the bark, but the contribution of N from the bark was non-negligible. Glycine accounted for 28.4% to 44.5% of the total N in bryophyte tissue, which implies that organic N might serve as an important N source. Increased N deposition increased the total N uptake, but did not alter the N preference of the epiphytic bryophytes. This study provides sound evidence that epiphytic bryophytes could take up N from the bark and wet deposition in both organic and inorganic N forms. It is thus important to consider organic N and bark N sources, which were usually neglected, when estimating the role of epiphytic bryophytes in N cycling and the impacts of N deposition on epiphytic bryophytes in cloud forests.

  17. Inorganic nitrogen supply and dissolved organic nitrogen abundance across the US Great Plains.

    PubMed

    Mobley, Megan L; Cleary, Matthew J; Burke, Ingrid C

    2014-01-01

    Across US Great Plains grasslands, a gradient of increasing mean annual precipitation from west to east corresponds to increasing aboveground net primary productivity (ANPP) and increasing N-limitation. Previous work has shown that there is no increase in net N mineralization rates across this gradient, leading to the question of where eastern prairie grasses obtain the nitrogen to support production. One as-yet unexamined source is soil organic N, despite abundant literature from other ecosystems showing that plants take up dissolved soil organic N. This study measured KCl-extractable dissolved organic N (DON) in surface soils across the grassland productivity gradient. We found that KCl-extractable DON pools increased from west to east. If available to and used by plants, this DON may help explain the high ANPP in the eastern Great Plains. These results suggest a need for future research to determine whether, in what quantities, and in what forms prairie grasses use organic N to support primary production.

  18. Organic nitrogen uptake is a significant contributor to nitrogen economy of subtropical epiphytic bryophytes

    PubMed Central

    Song, Liang; Lu, Hua-Zheng; Xu, Xing-Liang; Li, Su; Shi, Xian-Meng; Chen, Xi; Wu, Yi; Huang, Jun-Biao; Chen, Quan; Liu, Shuai; Wu, Chuan-Sheng; Liu, Wen-Yao

    2016-01-01

    Without any root contact with the soil, epiphytic bryophytes must experience and explore poor, patchy, and heterogeneous habitats; while, the nitrogen (N) uptake and use strategies of these organisms remain uncharacterized, which obscures their roles in the N cycle. To investigate the N sources, N preferences, and responses to enhanced N deposition in epiphytic bryophytes, we carried out an in situ manipulation experiment via the 15N labelling technique in an Asian cloud forest. Epiphytic bryophytes obtained more N from air deposition than from the bark, but the contribution of N from the bark was non-negligible. Glycine accounted for 28.4% to 44.5% of the total N in bryophyte tissue, which implies that organic N might serve as an important N source. Increased N deposition increased the total N uptake, but did not alter the N preference of the epiphytic bryophytes. This study provides sound evidence that epiphytic bryophytes could take up N from the bark and wet deposition in both organic and inorganic N forms. It is thus important to consider organic N and bark N sources, which were usually neglected, when estimating the role of epiphytic bryophytes in N cycling and the impacts of N deposition on epiphytic bryophytes in cloud forests. PMID:27460310

  19. BIOCONCENTRATION FACTORS FOR VOLATILE ORGANIC COMPOUNDS IN VEGETATION

    EPA Science Inventory

    Samples of air and leaves were taken at the University of Nevada-Las Vegas campus and analyzed for volatile organic compounds using vacuum distillation coupled with gas chromatography/mass spectrometry. The data were used to estimate the bioconcentration of volatile organic compo...

  20. LOSS OF ORGANIC CHEMICALS IN SOIL: PURE COMPOUND TREATABILITY STUDIES

    EPA Science Inventory

    Comprehensive screening data on the treatability of 32 organic chemicals in soil were developed. Of the evaluated chemicals, 22 were phenolic compounds. Aerobic batch laboratory microcosm experiments were conducted using two soils: an acidic clay soil with <1% organic matter and ...

  1. INTERACTIONS BETWEEN ORGANIC COMPOUNDS AND CYCLODEXTRIN-CLAY SYSTEMS

    EPA Science Inventory

    Computational and experimental techniques are combined in order to better understand interactions involving organic compounds and cyclodextrin (CD)-clay systems. CD-clay systems may have great potential in the containment of organic contaminants in the environment. This study w...

  2. Students' Understanding of Molecular Structure and Properties of Organic Compounds.

    ERIC Educational Resources Information Center

    Schmidt, Hans-Jurgen

    The purpose of this study was to investigate senior high school students' difficulties predicting the existence of hydrogen bridge bonds between organic molecules, investigate students' difficulties predicting the relative boiling points of simple organic compounds, and develop test questions that enable teachers to quickly get information about…

  3. 40 CFR 60.392 - Standards for volatile organic compounds

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 7 2012-07-01 2012-07-01 false Standards for volatile organic compounds 60.392 Section 60.392 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Automobile and Light Duty Truck Surface Coating Operations § 60.392 Standards for volatile organic...

  4. 40 CFR 60.392 - Standards for volatile organic compounds.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 7 2014-07-01 2014-07-01 false Standards for volatile organic compounds. 60.392 Section 60.392 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Automobile and Light Duty Truck Surface Coating Operations § 60.392 Standards for volatile organic...

  5. 40 CFR 60.392 - Standards for volatile organic compounds

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 6 2011-07-01 2011-07-01 false Standards for volatile organic compounds 60.392 Section 60.392 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Automobile and Light Duty Truck Surface Coating Operations § 60.392 Standards for volatile organic...

  6. 40 CFR 60.432 - Standard for volatile organic compounds.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 7 2013-07-01 2013-07-01 false Standard for volatile organic compounds. 60.432 Section 60.432 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Graphic Arts Industry: Publication Rotogravure Printing § 60.432 Standard for volatile organic...

  7. 40 CFR 60.392 - Standards for volatile organic compounds.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 7 2013-07-01 2013-07-01 false Standards for volatile organic compounds. 60.392 Section 60.392 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Automobile and Light Duty Truck Surface Coating Operations § 60.392 Standards for volatile organic...

  8. 40 CFR 60.432 - Standard for volatile organic compounds.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 7 2012-07-01 2012-07-01 false Standard for volatile organic compounds. 60.432 Section 60.432 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Graphic Arts Industry: Publication Rotogravure Printing § 60.432 Standard for volatile organic...

  9. 40 CFR 60.432 - Standard for volatile organic compounds.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 7 2014-07-01 2014-07-01 false Standard for volatile organic compounds. 60.432 Section 60.432 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Graphic Arts Industry: Publication Rotogravure Printing § 60.432 Standard for volatile organic...

  10. 40 CFR 60.432 - Standard for volatile organic compounds.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 6 2011-07-01 2011-07-01 false Standard for volatile organic compounds. 60.432 Section 60.432 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Graphic Arts Industry: Publication Rotogravure Printing § 60.432 Standard for volatile organic...

  11. 40 CFR 60.432 - Standard for volatile organic compounds.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 6 2010-07-01 2010-07-01 false Standard for volatile organic compounds. 60.432 Section 60.432 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Graphic Arts Industry: Publication Rotogravure Printing § 60.432 Standard for volatile organic...

  12. 40 CFR 60.392 - Standards for volatile organic compounds

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 6 2010-07-01 2010-07-01 false Standards for volatile organic compounds 60.392 Section 60.392 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Automobile and Light Duty Truck Surface Coating Operations § 60.392 Standards for volatile organic...

  13. Leveraging the beneficial compounds of organic and pasture milk

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Much discussion has arisen over the possible benefits of organic food, including milk. Organic milk comes from cows that are on pasture during the growing season, and would be expected to contain some compounds that are not found in animals receiving conventional feed, or at higher concentrations. ...

  14. Volatile and semivolatile organic compounds in laboratory peat fire emissions

    EPA Science Inventory

    Speciated volatile organic compounds (VOCs) and organic fine particulate matter (PM2.5) mass emission factors were determined from laboratory peat fire experiments. Peat samples originated from two wildlife reserves located near the coast of North Carolina, U.S. Gas and particula...

  15. Can volatile organic compounds be markers of sea salt?

    PubMed

    Silva, Isabel; Coimbra, Manuel A; Barros, António S; Marriott, Philip J; Rocha, Sílvia M

    2015-02-15

    Sea salt is a handmade food product that is obtained by evaporation of seawater in saltpans. During the crystallisation process, organic compounds from surroundings can be incorporated into sea salt crystals. The aim of this study is to search for potential volatile markers of sea salt. Thus, sea salts from seven north-east Atlantic Ocean locations (France, Portugal, Continental Spain, Canary Islands, and Cape Verde) were analysed by headspace solid-phase microextraction combined with comprehensive two-dimensional gas chromatography-time-of-flight mass spectrometry. A total of 165 compounds were detected, ranging from 32 to 71 compounds per salt. The volatile composition revealed the variability and individuality of each salt, and a set of ten compounds were detected in all samples. From these, seven are carotenoid-derived compounds that can be associated with the typical natural surroundings of ocean hypersaline environment. These ten compounds are proposed as potential volatile markers of sea salt.

  16. Regional characteristics of dry deposition of sulfur and nitrogen compounds at EANET sites in Japan from 2003 to 2008

    NASA Astrophysics Data System (ADS)

    Endo, Tomomi; Yagoh, Hiroaki; Sato, Keiichi; Matsuda, Kazuhide; Hayashi, Kentaro; Noguchi, Izumi; Sawada, Kiyoshi

    2011-02-01

    The regional characteristics of estimated dry deposition and total atmospheric deposition, including dry and wet deposition, at 10 EANET sites in Japan from April 2003 to March 2008 are discussed. The components examined for dry deposition were sulfur compounds (SO 2 and particulate SO 42-) and nitrogen compounds (HNO 3, NH 3, particulate NO 3-, and NH 4+). Dry deposition was calculated by the product of the deposition velocity estimated by the inferential method for forest and grass surfaces and the air concentration of each compound. The 5-year mean annual dry deposition amounts for sulfur and nitrogen compounds were in the range of 5-37 and 7-50 mmol m -2 year -1, respectively. The regional characteristics of dry deposition amounts were similar between sulfur and nitrogen compounds, which showed higher deposition in the Sea of Japan side and in the Western Japan. The 5-year mean annual total deposition amounts for sulfur and nitrogen compounds were in the range of 28-77 and 22-130 mmol m -2 year -1, respectively. The contribution of dry deposition to the total deposition amounts was 10-55% and 13-56% for sulfur and nitrogen compounds, respectively. The regional characteristic of total deposition was different between sulfur and nitrogen compounds. Total deposition amounts in Japan were larger than those in CASTNET and EMEP because of high wet deposition, which implied that the increasing emissions of air pollutants in East Asia caused high atmospheric depositions.

  17. Lysine biosynthesis and nitrogen metabolism in quinoa (Chenopodium quinoa): study of enzymes and nitrogen-containing compounds.

    PubMed

    Varisi, Vanderlei A; Camargos, Liliane S; Aguiar, Leandro F; Christofoleti, Renata M; Medici, Leonardo O; Azevedo, Ricardo A

    2008-01-01

    Aspartate kinase (AK, EC 2.7.2.4), homoserine dehydrogenase (HSDH, EC 1.1.1.3) and dihydrodipicolinate synthase (DHDPS, EC 4.2.1.52) were isolated and partially purified from immature Chenopodium quinoa Willd seeds. Enzyme activities were studied in the presence of the aspartate-derived amino acids lysine, threonine and methionine and also the lysine analogue S-2-aminoethyl-l-cysteine (AEC), at 1 mM and 5 mM. The results confirmed the existence of, at least, two AK isoenzymes, one inhibited by lysine and the other inhibited by threonine, the latter being predominant in quinoa seeds. HSDH activity was also shown to be partially inhibited by threonine, whereas some of the activity was resistant to the inhibitory effect, indicating the presence of two isoenzymes, one resistant and another sensitive to threonine inhibition. Only one DHDPS isoenzyme highly sensitive to lysine inhibition was detected. The results suggest that the high concentration of lysine observed in quinoa seeds is possibly due to a combined effect of increased lysine synthesis and accumulation in the soluble form and/or as protein lysine. Nitrogen assimilation was also investigated and based on nitrate content, nitrate reductase activity, amino acid distribution and ureide content, the leaves were identified as the predominant site of nitrate reduction in this plant species. The amino acid profile analysis in leaves and roots also indicated an important role of soluble glutamine as a nitrogen transporting compound.

  18. ACE: Detecting Volatile Organic Compounds from Orbit

    NASA Astrophysics Data System (ADS)

    Harrison, Jeremy J.; Allen, Nicholas D. C.; Bernath, Peter F.

    2010-12-01

    High-resolution infrared absorption cross sections for ethane, propane (both in the 3 μm region) and acetone (in the 3 μm and 5-8 μm regions) have been determined from spectra recorded using a high-resolution FTIR spectrometer (Bruker IFS 125/HR). Data are presented for mixtures with dry synthetic air at 0.015 cm-1 resolution (calculated as 0.9/MOPD using the Bruker definition of resolution), at a number of temperatures and pressures appropriate for atmospheric conditions. Intensities were calibrated using spectra taken from the Pacific Northwest National Laboratory (PNNL) IR database. Methane measurements are currently being performed in the 3 μm region in order to retrieve line mixing parameters, which will be used in an improved ACE forward model to minimize CH4 residuals in the retrievals of organic species. Preliminary retrievals of acetone from ACE spectra using a microwindow from 1364.7 to 1367.1 cm-1 have been performed.

  19. The development of a new technical platform to measure soil organic nitrogen cycling processes by microbes

    NASA Astrophysics Data System (ADS)

    Hu, Yuntao; Richter, Andreas; Wanek, Wolfgang

    2016-04-01

    nucleic acids) are prepared by enzymatic and/or acid digestion of the polymers. Different UPLC separation columns (Hypercarb, HiliC and C18) make it possible to separate more than 100 related monomers and oligomers produced during polymer decomposition, a prerequisite for analyzing the concentrations and isotope kinetics of decomposition products in complex soil samples. The benchtop Orbitrap mass analyzer has a nominal mass resolving power of 100,000 (FWHM at m/z 200), which enables us to separate compounds that are 13C- and 15N-labelled (mass difference: 0.00632) in the same compound, allowing tracing carbon and nitrogen isotopes in the same compound in IPD experiments. With the accurate masses, retention times and the isotopic pattern we can quantify and qualify the target decomposition products and their isotope kinetics during soil incubation experiments. This will enable us to estimate in situ decomposition rates of the major organic nitrogen polymers in soils, allowing new insights into the major controls of the most important step in soil organic nitrogen recycling.

  20. Analysis of organic compounds' degradation and electricity generation in anaerobic fluidized bed microbial fuel cell for coking wastewater treatment.

    PubMed

    Liu, Xinmin; Wu, Jianjun; Guo, Qingjie

    2017-02-22

    A single-chambered packing-type anaerobic fluidized microbial fuel cell (AFBMFC) with coking wastewater (CWW) as fuel was built to treat CWW, which not only has high treating efficiency, but also can convert organic matter in wastewater into electricity. AFBMFC was constructed by using anaerobic sludge that was domesticated as inoculation sludge, which was used to biochemically treat CWW. The organic compounds in CWW were extracted by liquid-liquid extraction step by step every day. The extraction phase was concentrated by a rotary evaporator and a nitrogen sweeping device and was analyzed by GC-MS. And the electricity-generation performances of AFBMFC were investigated. The results show that the composition of CWW was complicated, which mainly contains hydrocarbons, phenols, nitrogenous organic compounds, alcohols and aldehydes, esters and acids and so on. After a cycle of anaerobic biochemical treatment, the content of organic compounds in the effluent decreased significantly. After the treatment of AFBMFC, 99.9% phenols, 98.4% alcohol and aldehydes and 95.3% nitrogenous compounds were biodegraded. In the effluent, some new compounds (such as tricosane and dibutyl phthalate) were produced. The chemical oxygen demand (COD) of CWW decreased from 3372 to 559 mg/L in the closed-circuit microbial fuel cell, and the COD removal was 83.4 ± 1.0%. The maximum power density of AFBMFC was 2.13 ± 0.01 mW m(-2).

  1. Use of Bromine and Bromo-Organic Compounds in Organic Synthesis.

    PubMed

    Saikia, Indranirekha; Borah, Arun Jyoti; Phukan, Prodeep

    2016-06-22

    Bromination is one of the most important transformations in organic synthesis and can be carried out using bromine and many other bromo compounds. Use of molecular bromine in organic synthesis is well-known. However, due to the hazardous nature of bromine, enormous growth has been witnessed in the past several decades for the development of solid bromine carriers. This review outlines the use of bromine and different bromo-organic compounds in organic synthesis. The applications of bromine, a total of 107 bromo-organic compounds, 11 other brominating agents, and a few natural bromine sources were incorporated. The scope of these reagents for various organic transformations such as bromination, cohalogenation, oxidation, cyclization, ring-opening reactions, substitution, rearrangement, hydrolysis, catalysis, etc. has been described briefly to highlight important aspects of the bromo-organic compounds in organic synthesis.

  2. Catalytic combustion of volatile organic compounds.

    PubMed

    Everaert, K; Baeyens, J

    2004-06-18

    Despite the success of adsorption and thermal incineration of (C)VOC emissions, there is still a need for research on techniques which are both economically more favorable and actually destroy the pollutants rather than merely remove them for recycling elsewhere in the biosphere. The catalytic destruction of (C)VOC to CO2, H2O and HCl/Cl2 appears very promising in this context and is the subject of the present paper. The experiments mainly investigate the catalytic combustion of eight target compounds, all of which are commonly encountered in (C)VOC emissions and/or act as precursors for the formation of PCDD/F. Available literature on the different catalysts active in the oxidation of (C)VOC is reviewed and the transition metal oxide complex V2O5-WO3/TiO2 appears most suitable for the current application. Different reactor geometries (e.g. fixed pellet beds, honeycombs, etc.) are also described. In this research a novel catalyst type is introduced, consisting of a V2O5-WO3/TiO2 coated metal fiber fleece. The conversion of (C)VOC by thermo-catalytic reactions is governed by both reaction kinetics and reaction equilibrium. Full conversion of all investigated VOC to CO2, Cl2, HCl and H2O is thermodynamically feasible within the range of experimental conditions used in this work (260-340 degrees C, feed concentrations 30-60 ppm). A first-order rate equation is proposed for the (C)VOC oxidation reactions. The apparent rate constant is a combination of reaction kinetics and mass transfer effects. The oxidation efficiencies were measured with various (C)VOC in the temperature range of 260-340 degrees C. Literature data for oxidation reactions in fixed beds and honeycomb reactors are included in the assessment. Mass transfer resistances are calculated and are generally negligible for fleece reactors and fixed pellet beds, but can be of importance for honeycomb monoliths. The experimental investigations demonstrate: (i) that the conversion of the hydrocarbons is

  3. Molecular Mechanics Study of Enzymatic Relationships in a Group of Nitrogenous Compounds.

    NASA Astrophysics Data System (ADS)

    Strickland, Alan Douglas

    Molecular mechanics using the MMX parameterization was used to model a series of nitrogen containing compounds to determine their lowest energy conformations. Measurements of dihedral angles and atomic distances were then correlated with results of enzymatic reactions on the nitrogen containing compounds. A preferred conformation of the compounds was found which allowed enzymatic action. Repeating the modeling of the compounds with the PM3 semi-empirical technique confirmed the preferred conformation. Practicum two. The Industrial Practicum report on "Development of polysaccharide derivatives for industrial Uses." Since many polysaccharides are inexpensive, this exploratory project was designed to prepare derivatives of carbohydrates and evaluate their industrial uses. Derivatives of dextran, carboxymethyl cellulose, and cellulose were prepared using three reaction schemes. Periodate oxidation of the carbohydrate followed by reductive amination was used with several amines. Linking various amines to carbohydrates through epichlorohydrin was performed. Reacting carbohydrates with 2-oxazolidinone was explored. Uses of the derivatives were explored. Practicum one. The study on "Thermochemistry of strained cycloalkenes: Experimental and computational studies." Pulsed time-resolved photoacoustic calorimetry in combination with quantum yield determinations revealed the relaxed triplet energy of 1-phenylcyclooctene and the energy of geometric isomerization of cis-1-phenylcyclooctene. Computational approaches for modeling strained cycloalkenes were evaluated against the experimental results.

  4. Composition and major sources of organic compounds in urban aerosols

    NASA Astrophysics Data System (ADS)

    Bi, Xinhui; Simoneit, Bernd R. T.; Sheng, Guoying; Ma, Shexia; Fu, Jiamo

    Total suspended particles (TSP), collected during June 2002 to July 2003 in Guangzhou, a typical economically developed city in South China, were analyzed for the organic compound compositions using gas chromatography-mass spectrometry (GC/MS). Over 140 organic compounds were detected in the aerosols and grouped into different classes including n-alkanes, hopanoids, polycyclic aromatic hydrocarbons, alkanols, fatty acids, dicarboxylic acids excluding oxalic acid, polyols/polyacids, lignin products, phytosterols, phthalates and water-soluble sugars. The total amounts of the identified organic compounds including unresolved complex mixture (UCM) ranged from 3112 ng/m 3 in spring to 5116 ng/m 3 in winter, comprising on seasonal average 2.8% of TSP. Primary organic compounds peaked in winter although there are no heating systems burning fuels in Guangzhou. The highest saccharide levels occurred in fall due to agricultural activities. This study demonstrated that utilization of fossil fuels, biomass burning, soil resuspension and plastic/refuse burning are the major contributors to the identified organic compounds in the urban atmosphere of South China.

  5. Topological research on diamagnetic susceptibilities of organic compounds.

    PubMed

    Mu, Lailong; Feng, Changjun; He, Hongmei

    2008-02-01

    A novel molecular connectivity index, (m)chi('), based on the adjacency matrix of molecular graphs and novel atomic valence connectivities, delta(i)(') for predicting the molar diamagnetic susceptibilities of organic compounds is proposed. The delta(i)(') is defined as: delta(i)(') = delta(i)(nu) x Ei=12:625, where delta(i)(nu) and E(i) are the atomic valence connectivity and the valence orbital energy of atom i, respectively. A good QSPR model for molar diamagnetic susceptibilities can be constructed from (0)chi('), (1)chi('), (2)chi(') and (4)chi(p)(') using multivariate linear regression (MLR). The correlation coefficient r, standard error, and average absolute deviation of the MLR model are 0.9918, 5.56 cgs, and 4.26 cgs, respectively, for the 721 organic compounds tested (training set). Cross-validation using the leave-one-out method demonstrates that the MLR model is highly reliable statistically. Using the MLR model, the average absolute deviations of the predicted values of molar diamagnetic susceptibility of another 360 organic compounds (test set) is 4.34 cgs. The results show that the current method is more effective than literature methods for estimating the molar diamagnetic susceptibility of an organic compound. The MLR method thus provides an acceptable model for the prediction of molar diamagnetic susceptibilities of organic compounds.

  6. Well-purging criteria for sampling purgeable organic compounds

    USGS Publications Warehouse

    Gibs, J.; Imbrigiotta, T.E.

    1990-01-01

    The results indicate that 1) purgeable organic compound concentrations stabilized when three casing volume were purged in only 55% of the cases evaluated in this study, 2) purgeable organic compounds concentrations did not consistently follow the temporal variation of, nor stabilize at the same time as, the measure field characteristics, and 3) purging to achieve hydraulic equilibrium between casing and aquifer water consistently underestimated the time and casing volumes needed to achieve stable values of water-quality measurements in highly transmissive aquifers. The conclusion from these data is that none of the previously recommended criteria for purging a well can be applied reliably to collecting a "representative' sample of purgeable organic compounds. These results indicate that the criteria for purging a well prior to sampling for purgeable organic compounds must take into account other factors, such as the unique hydrogeologic characteristics of a site, the nature and extent of purgeable organic compounds present, and areal extent of the contamination, the well construction, and the sampling objectives of the investigation. -from Authors

  7. Improving rubber concrete by waste organic sulfur compounds.

    PubMed

    Chou, Liang-Hisng; Lin, Chun-Nan; Lu, Chun-Ku; Lee, Cheng-Haw; Lee, Maw-Tien

    2010-01-01

    In this study, the use of crumb tyres as additives to concrete was investigated. For some time, researchers have been studying the physical properties of concrete to determine why the inclusion of rubber particles causes the concrete to degrade. Several methods have been developed to improve the bonding between rubber particles and cement hydration products (C-S-H) with the hope of creating a product with an improvement in mechanical strength. In this study, the crumb tyres were treated with waste organic sulfur compounds from a petroleum refining factory in order to modify their surface properties. Organic sulfur compounds with amphiphilic properties can enhance the hydrophilic properties of the rubber and increase the intermolecular interaction forces between rubber and C-S-H. In the present study, a colloid probe of C-S-H was prepared to measure these intermolecular interaction forces by utilizing an atomic force microscope. Experimental results showed that rubber particles treated with waste organic sulfur compounds became more hydrophilic. In addition, the intermolecular interaction forces increased with the adsorption of waste organic sulfur compounds on the surface of the rubber particles. The compressive, tensile and flexural strengths of concrete samples that included rubber particles treated with organic sulfur compound also increased significantly.

  8. The nitrogen source impacts major volatile compounds released by Saccharomyces cerevisiae during alcoholic fermentation.

    PubMed

    Barbosa, Catarina; Mendes-Faia, Arlete; Mendes-Ferreira, Ana

    2012-11-15

    Sulphur-containing amino acids, cysteine and methionine, are generally found in very low concentrations in grape-juice. The objective of this study was to identify the effects of methionine on aroma compounds formation. Nitrogen source effects on growth, fermentative behaviour and aroma compounds formation were evaluated in three strains of Saccharomyces cerevisiae cultivated in batch under moderate nitrogen concentration, 267mg YAN/L, supplied as di-ammonium phosphate (DAP), a mixture of amino acids with (AA) or without methionine (AA(wMet)), and a mixture of AA plus DAP. Fermentative vigour and final biomass yields were dependent on the nitrogen source, for each of the strains tested, in particular for EC1118. Additionally, despite the strain-dependent behaviour with respect to the basal level of H(2)S produced, the comparison of treatments AA and AA(wMet) showed that presence of methionine suppressed H(2)S production in all strains tested, and altered aroma compound formation, particularly some of those associated with fruity and floral characters which were consistently more produced in AA(wMet). Moreover, DAP supplementation resulted in a remarkable increase in H(2)S formation, but no correlation between sulphide produced and yeast fermentative vigour was observed. Results suggest that the use of different nitrogen sources results in the production of wines with divergent aroma profiles, most notably when EC1118 strain is used. Methionine determination and its management prior to fermentation are crucial for suppressing H(2)S and to endowing beverages with diverse sensory traits.

  9. Identification of nitrogenous organic species in Titan aerosols analogs: Nitrogen fixation routes in early atmospheres

    NASA Astrophysics Data System (ADS)

    He, Chao; Smith, Mark A.

    2013-09-01

    Titan, an icy world surrounded by auburn organic haze, is considered as one of the best targets for studying abiotic planetary organic chemistry. In spite of a great many efforts being made, the chemistry in Titan’s atmosphere and its resulting chemical structures are still not fully understood. In our previous work, we have investigated the structure of Titan aerosols analogs (tholin) by NMR and identified hexamethylenetetramine as a dominant small molecule in Titan tholin. Here we report a more complete and definitive structural investigation of the small molecule inventory in Titan tholin. We identified several nitrogenous organic molecules including cyanamide, guanidine, 2-cyanoguanidine, melamine, N‧-cyanoformamidine and 1,2,4-triazole in Titan tholin by using NMR and GC-MS and standard sample comparison. The structural characteristics of these molecules suggest a possible formation pathway from the reaction of HCN and NH3, both of which are known to exist in appreciable density in the atmosphere and were tentatively detected by the Huygens probe.

  10. Bonded-phase extraction column isolation of organic compounds in groundwater at a hazardous waste site

    USGS Publications Warehouse

    Rostad, C.E.; Pereira, W.E.; Ratcliff, S.M.

    1984-01-01

    A procedure for isolation of hazardous organic compounds from water for gas chromatography/mass spectrometry analysis Is presented and applied to creosote- and pentachlorophenol-contaminated groundwater resulting from wood-treatment processes. This simple procedure involved passing a 50-100-mL sample through a bonded-phase extraction column, eluting the trapped organic compounds from the column with 2-4 mL of solvent, and evaporating the sample to 100 ??L with a stream of dry nitrogen, after which the sample was ready for gas chromatography/mass spectrometry analysis. Representative compounds indicative of creosote contamination were used for recovery and precision studies from the cyclohexyl-bonded phase. Recovery of these compounds from n-octyl-, n-octadecyl-, cyclohexyl-, and phenyl-bonded phases was compared. The bonded phase that exhibited the best recovery and least bias toward acidic or basic cmpounds was the n-octadecyl phase. Detailed compound Identification Is given for compounds Isolated from creosote- and pentachlorophenol-contaminated groundwater using the cyclohexyl-bonded phase.

  11. Emission characteristics of nitrogen- and sulfur-containing odorous compounds during different sewage sludge chemical conditioning processes.

    PubMed

    Liu, Huan; Luo, Guang-Qian; Hu, Hong-Yun; Zhang, Qiang; Yang, Jia-Kuan; Yao, Hong

    2012-10-15

    Chemical conditioners are often used to enhance sewage sludge dewaterability through altering sludge properties and flocs structure, both affect odorous compounds emissions not only during sludge conditioning but also in subsequent sludge disposal. This study was to investigate emission characteristics of ammonia (NH(3)), sulfur dioxide (SO(2)), hydrogen sulfide (H(2)S) and carbonyl sulfide (COS) generated from sewage sludge conditioned by three representative conditioners, i.e., organic polymers, iron salts and skeleton builders, F-S (Fenton's reagent and skeleton builders) composite conditioner. The results demonstrate that polyacrylamide (PAM) has an insignificant effect on emission characteristics of nitrogen- and sulfur-containing odorous compounds, because the properties, sulfur and nitrogen speciations are similar in PAM-conditioned sludge and raw sludge (RS). Significant increases of SO(2) and H(2)S emissions in the H(2)SO(4) conditioning process were observed due to the accelerated decomposition of sulfur-containing amino acids in acidic environment. Fenton peroxidation facilitates the formation of COS. CaO can reduce sulfur-containing gases emission via generation of calcium sulfate. However, under strong alkaline conditions, free ammonia or protonated amine in sludge can be easily converted to volatile ammonia, resulting in a significant release of NH(3).

  12. Refractory dissolved organic nitrogen accumulation in high-elevation lakes.

    PubMed

    Goldberg, S J; Ball, G I; Allen, B C; Schladow, S G; Simpson, A J; Masoom, H; Soong, R; Graven, H D; Aluwihare, L I

    2015-02-23

    The role of dissolved organic matter (DOM) as either a sink for inorganic nutrients or an additional nutrient source is an often-neglected component of nutrient budgets in aquatic environments. Here, we examined the role of DOM in reactive nitrogen (N) storage in Sierra Nevada (California, USA) lakes where atmospheric deposition of N has shifted the lakes toward seasonal phosphorus (P)-limitation. Nuclear magnetic resonance (NMR) spectroscopy and isotope analyses performed on DOM isolated from Lake Tahoe reveal the accumulation of refractory proteinaceous material with a 100-200-year residence time. In contrast, smaller lakes in the same watershed contain DOM with typical terrestrial characteristics, indicating that proteins in Lake Tahoe are autochthonously produced. These data support the role of DOM as a possible sink for reactive N in these lake ecosystems and identify a potential role for DOM in affecting the inorganic nutrient stoichiometry of these environments.

  13. Origin of organic matter in early solar system. VI - Catalytic synthesis of nitriles, nitrogen bases and porphyrin-like pigments.

    NASA Technical Reports Server (NTRS)

    Hayatsu, R.; Matsuoka, S.; Anders, E.; Studier, M. H.

    1972-01-01

    A variety of nitrogen compounds have been synthesized by a static Fischer-Tropsch type reaction from CO, D2 and ND3, with Ni-Fe and Al2O3 catalysts. In this reaction, the gas is heated to 500-700 C for about 0.5 hr, and then cycled through lower temperatures (100-400 C) for 1-14 days. Products were analyzed by mass spectrometry in conjunction with gas chromatography and other chromatographic techniques. Compounds produced include alkyl cyanides, pyrroles, porphyrin-like compounds, guanidines, hydantoin, uracil and its derivatives, thymine, adenine, guanine, xanthine, melamine, as well as alkanes, alkenes and aromatic hydrocarbons. Such reactions may have been involved in the production of interstellar molecules, organic compounds in meteorites, and prebiotic organic matter on planets.

  14. Determination of sulfur and nitrogen compounds during the processing of dry fermented sausages and their relation to amino acid generation.

    PubMed

    Corral, Sara; Leitner, Erich; Siegmund, Barbara; Flores, Mónica

    2016-01-01

    The identification of odor-active sulfur and nitrogen compounds formed during the processing of dry fermented sausages was the objective of this study. In order to elucidate their possible origin, free amino acids (FAAs) were also determined. The volatile compounds present in the dry sausages were extracted using solvent assisted flavor evaporation (SAFE) and monitored by one and two-dimensional gas chromatography with different detectors: mass spectrometry (MS), nitrogen phosphorous (NPD), flame photometric (FPD) detectors, as well as gas chromatography-olfactometry. A total of seventeen sulfur and nitrogen compounds were identified and quantified. Among them, 2-acetyl-1-pyrroline was the most potent odor active compound, followed by methional, ethylpyrazine and 2,3-dihydrothiophene characterized by toasted, cooked potato, and nutty notes. The degradation of FAAs, generated during processing, was related to the production of aroma compounds, such as methionine forming methional and benzothiazole while ornithine was the precursor compound for 2-acetyl-1-pyrroline and glycine for ethylpyrazine.

  15. Particulate organic carbon and nitrogen export from major Arctic rivers

    NASA Astrophysics Data System (ADS)

    McClelland, J. W.; Holmes, R. M.; Peterson, B. J.; Raymond, P. A.; Striegl, R. G.; Zhulidov, A. V.; Zimov, S. A.; Zimov, N.; Tank, S. E.; Spencer, R. G. M.; Staples, R.; Gurtovaya, T. Y.; Griffin, C. G.

    2016-05-01

    Northern rivers connect a land area of approximately 20.5 million km2 to the Arctic Ocean and surrounding seas. These rivers account for ~10% of global river discharge and transport massive quantities of dissolved and particulate materials that reflect watershed sources and impact biogeochemical cycling in the ocean. In this paper, multiyear data sets from a coordinated sampling program are used to characterize particulate organic carbon (POC) and particulate nitrogen (PN) export from the six largest rivers within the pan-Arctic watershed (Yenisey, Lena, Ob', Mackenzie, Yukon, Kolyma). Together, these rivers export an average of 3055 × 109 g of POC and 368 × 109 g of PN each year. Scaled up to the pan-Arctic watershed as a whole, fluvial export estimates increase to 5767 × 109 g and 695 × 109 g of POC and PN per year, respectively. POC export is substantially lower than dissolved organic carbon export by these rivers, whereas PN export is roughly equal to dissolved nitrogen export. Seasonal patterns in concentrations and source/composition indicators (C:N, δ13C, Δ14C, δ15N) are broadly similar among rivers, but distinct regional differences are also evident. For example, average radiocarbon ages of POC range from ~2000 (Ob') to ~5500 (Mackenzie) years before present. Rapid changes within the Arctic system as a consequence of global warming make it challenging to establish a contemporary baseline of fluvial export, but the results presented in this paper capture variability and quantify average conditions for nearly a decade at the beginning of the 21st century.

  16. Volatile organic compounds in Gulf of Mexico sediments

    SciTech Connect

    McDonald, T.J.

    1988-01-01

    Volatile organic compounds (VOC), concentrations and compositions were documented for estuarine, coastal, shelf, slope, and deep water sediments from the Gulf of Mexico. VOC were measured (detection limit >0.01 ppb) using a closed-loop stripping apparatus with gas chromatography (GC) and flame ionization, flame photometric, and mass spectrometric detectors. The five primary sources of Gulf of Mexico sediment VOC are: (1) planktonic and benthic fauna and flora; (2) terrestrial material from riverine and atmospheric deposition; (3) anthropogenic inputs: (4) upward migration of hydrocarbons; and (5) transport by bottom currents or slumping. Detected organo-sulfur compounds include alkylated sulfides, thiophene, alkylated thiophenes, and benzothiophenes. Benzothiophenes are petroleum related. Low molecular weight organo-sulfur compounds result from the biological oxidation of organic matter. A lack of organosulfur compounds in the reducing environment of the Orca Basin may result from a lack of free sulfides which are necessary for their production.

  17. Soil Organic Chemistry.

    ERIC Educational Resources Information Center

    Anderson, G.

    1979-01-01

    A brief review is presented of some of the organic compounds and reactions that occur in soil. Included are nitrogenous compounds, compounds of phosphorus and sulfur, carbohydrates, phenolic compounds, and aliphatic acids. (BB)

  18. Modeling the effects of organic nitrogen uptake by plants on the carbon cycling of boreal ecosystems

    NASA Astrophysics Data System (ADS)

    Zhu, Q.; Zhuang, Q.

    2013-08-01

    Boreal forest and tundra are the major ecosystems in the northern high latitudes in which a large amount of carbon is stored. These ecosystems are nitrogen-limited due to slow mineralization rate of the soil organic nitrogen. Recently, abundant field studies have found that organic nitrogen is another important nitrogen supply for boreal ecosystems. In this study, we incorporated a mechanism that allowed boreal plants to uptake small molecular amino acids into a process-based biogeochemical model, the Terrestrial Ecosystem Model (TEM), to evaluate the impact of organic nitrogen uptake on ecosystem carbon cycling. The new version of the model was evaluated at both boreal forest and tundra sites. We found that the modeled organic nitrogen uptake accounted for 36-87% of total nitrogen uptake by plants in tundra ecosystems and 26-50% for boreal forests, suggesting that tundra ecosystem might have more relied on the organic form of nitrogen than boreal forests. The simulated monthly gross ecosystem production (GPP) and net ecosystem production (NEP) tended to be larger with the new version of the model since the plant uptake of organic nitrogen alleviated the soil nitrogen limitation especially during the growing season. The sensitivity study indicated that the most important factors controlling the plant uptake of organic nitrogen were the maximum root uptake rate (Imax) and the radius of the root (r0) in our model. The model uncertainty due to uncertain parameters associated with organic nitrogen uptake at tundra ecosystem was larger than at boreal forest ecosystems. This study suggests that considering the organic nitrogen uptake by plants is important to boreal ecosystem carbon modeling.

  19. Volatile and semivolatile organic compounds in laboratory peat fire emissions

    NASA Astrophysics Data System (ADS)

    George, Ingrid J.; Black, Robert R.; Geron, Chris D.; Aurell, Johanna; Hays, Michael D.; Preston, William T.; Gullett, Brian K.

    2016-05-01

    In this study, volatile and semi-volatile organic compound (VOCs and SVOCs) mass emission factors were determined from laboratory peat fire experiments. The peat samples originated from two National Wildlife Refuges on the coastal plain of North Carolina, U.S.A. Gas- and particle-phase organic compounds were quantified by gas chromatography-mass spectrometry and by high pressure liquid chromatography. Hazardous air pollutants (HAPs) accounted for a large fraction (∼60%) of the speciated VOC emissions from peat burning, including large contributions of acetaldehyde, formaldehyde, benzene, toluene, and chloromethane. In the fine particle mass (PM2.5), the following organic compound classes were dominant: organic acids, levoglucosan, n-alkanes, and n-alkenes. Emission factors for the organic acids in PM2.5 including n-alkanoic acids, n-alkenoic acids, n-alkanedioic acids, and aromatic acids were reported for the first time for peat burning, representing the largest fraction of organic carbon (OC) mass (11-12%) of all speciated compound classes measured in this work. Levoglucosan contributed to 2-3% of the OC mass, while methoxyphenols represented 0.2-0.3% of the OC mass on a carbon mass basis. Retene was the most abundant particulate phase polycyclic aromatic hydrocarbon (PAH). Total HAP VOC and particulate PAH emissions from a 2008 peat wildfire in North Carolina were estimated, suggesting that peat fires can contribute a large fraction of state-wide HAP emissions.

  20. GROUNDWATER TRANSPORT OF HYDROPHOBIC ORGANIC COMPOUNDS IN THE PRESENCE OF DISSOLVED ORGANIC MATTER

    EPA Science Inventory

    The effects of dissolved organic matter (DOM) on the transport of hydrophobic organic compounds in soil columns were investigated. Three compounds (naphthalene, phenanthrene and DDT) that spanned three orders of magnitude in water solubility were used. Instead of humic matter, mo...

  1. Compositions comprising a polypeptide having cellulolytic enhancing activity and a nitrogen-containing compound and uses thereof

    DOEpatents

    Quinlan, Jason; Xu, Feng; Sweeney, Matthew

    2016-05-31

    The present invention relates to compositions comprising: a polypeptide having cellulolytic enhancing activity and a nitrogen-containing compound. The present invention also relates to methods of using the compositions.

  2. SEASONAL AND ANNUAL MODELING OF REDUCED NITROGEN COMPOUNDS OVER THE EASTERN UNITED STATES: EMISSIONS, AMBIENT LEVELS, AND DEPOSITION AMOUNTS

    EPA Science Inventory

    Detailed description of the distributions and seasonal trends of atmospheric nitrogen compounds is of considerable interest given their role in formation of acidic substances, tropospheric ozone and particulate matter and nutrient loading effects resulting from their deposition t...

  3. Retardation effect of nitrogen compounds and condensed aromatics on shale oil catalytic cracking processing and their characterization.

    PubMed

    Li, Nan; Chen, Chen; Wang, Bin; Li, Shaojie; Yang, Chaohe; Chen, Xiaobo

    Untreated shale oil, shale oil treated with HCl aqueous solution and shale oil treated with HCl and furfural were used to do comparative experiments in fixed bed reactors. Nitrogen compounds and condensed aromatics extracted by HCl and furfural were characterized by electrospray ionization Fourier transform cyclotron resonance mass spectrometry and gas chromatography and mass spectrometry, respectively. Compared with untreated shale oil, the conversion and yield of liquid products increased considerably after removing basic nitrogen compounds by HCl extraction. Furthermore, after removing nitrogen compounds and condensed aromatics by both HCl and furfural, the conversion and yield of liquid products further increased. In addition, N1 class species are predominant in both basic and non-basic nitrogen compounds, and they are probably indole, carbazole, cycloalkyl-carbazole, pyridine and cycloalkyl-pyridine. As for the condensed aromatics, most of them possess aromatic rings with two to three rings and zero to four carbon atom.

  4. Comparing compound-specific and bulk stable nitrogen isotope trophic discrimination factors across multiple freshwater fish species and diets

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The use of nitrogen stable isotopes for estimation of animal trophic position has become an indispensable approach in food web ecology. Compound-specific isotope analysis of amino acids is a new approach for estimating trophic position that may overcome key issues associated with nitrogen stable iso...

  5. Dosimeter for monitoring vapors and aerosols of organic compounds

    DOEpatents

    Vo-Dinh, Tuan

    1987-01-01

    A dosimeter is provided for collecting and detecting vapors and aerosols of organic compounds. The dosimeter comprises a lightweight, passive device that can be conveniently worn by a person as a badge or placed at a stationary location. The dosimeter includes a sample collector comprising a porous web treated with a chemical for inducing molecular displacement and enhancing phosphorescence. Compounds are collected onto the web by molecular diffusion. The web also serves as the sample medium for detecting the compounds by a room temperature phosphorescence technique.

  6. Dosimeter for monitoring vapors and aerosols of organic compounds

    DOEpatents

    Vo-Dinh, T.

    1987-07-14

    A dosimeter is provided for collecting and detecting vapors and aerosols of organic compounds. The dosimeter comprises a lightweight, passive device that can be conveniently worn by a person as a badge or placed at a stationary location. The dosimeter includes a sample collector comprising a porous web treated with a chemical for inducing molecular displacement and enhancing phosphorescence. Compounds are collected onto the web by molecular diffusion. The web also serves as the sample medium for detecting the compounds by a room temperature phosphorescence technique. 7 figs.

  7. Organic compounds in indoor air—their relevance for perceived indoor air quality?

    NASA Astrophysics Data System (ADS)

    Wolkoff, Peder; Nielsen, Gunnar D.

    It is generally believed that indoor air pollution, one way or another may cause indoor air complaints. However, any association between volatile organic compounds (VOCs) concentrations and increase of indoor climate complaints, like the sick-building syndrome symptoms, is not straightforward. The reported symptom rates of, in particular, eye and upper airway irritation cannot generally be explained by our present knowledge of common chemically non-reactive VOCs measured indoors. Recently, experimental evidence has shown those chemical reactions between ozone (either with or without nitrogen dioxide) and unsaturated organic compounds (e.g. from citrus and pine oils) produce strong eye and airway irritating species. These have not yet been well characterised by conventional sampling and analytical techniques. The chemical reactions can occur indoors, and there is indirect evidence that they are associated with eye and airway irritation. However, many other volatile and non-volatile organic compounds have not generally been measured which could equally well have potent biological effects and cause an increase of complaint rates, and posses a health/comfort risk. As a consequence, it is recommended to use a broader analytical window of organic compounds than the classic VOC window as defined by the World Health Organisation. It may include hitherto not yet sampled or identified intermediary species (e.g., radicals, hydroperoxides and ionic compounds like detergents) as well as species deposited onto particles. Additionally, sampling strategies including emission testing of building products should carefully be linked to the measurement of organic compounds that are expected, based on the best available toxicological knowledge, to have biological effects at indoor concentrations.

  8. Simplified Production of Organic Compounds Containing High Enantiomer Excesses

    NASA Technical Reports Server (NTRS)

    Cooper, George W. (Inventor)

    2015-01-01

    The present invention is directed to a method for making an enantiomeric organic compound having a high amount of enantiomer excesses including the steps of a) providing an aqueous solution including an initial reactant and a catalyst; and b) subjecting said aqueous solution simultaneously to a magnetic field and photolysis radiation such that said photolysis radiation produces light rays that run substantially parallel or anti-parallel to the magnetic field passing through said aqueous solution, wherein said catalyst reacts with said initial reactant to form the enantiomeric organic compound having a high amount of enantiomer excesses.

  9. Measurements of bromine containing organic compounds at the tropical tropopause

    NASA Astrophysics Data System (ADS)

    Schauffler, S. M.; Atlas, E. L.; Flocke, F.; Lueb, R. A.; Stroud, V.; Travnicek, W.

    The amount of bromine entering the stratosphere from organic source gases is a primary factor involved in determining the magnitude of bromine catalyzed loss of ozone. Thirty two whole air samples were collected at the tropical tropopause during the NASA STRAT Campaign in Feb., Aug., and Dec., 1996 and were analyzed for brominated organic compounds. Total organic bromine was 17.4±0.9 ppt with 55% from methyl bromide, 38% from the Halons, 6% from dibromomethane, and 0.8% from bromochloromethane and dichlorobromomethane. One flight showed the presence of 0.42 ppt of additional organic bromine from bromoform and dibromochloromethane.

  10. Detection of Organic Compounds with Whole-Cell Bioluminescent Bioassays

    PubMed Central

    Xu, Tingting; Close, Dan; Smartt, Abby; Ripp, Steven

    2015-01-01

    Natural and manmade organic chemicals are widely deposited across a diverse range of ecosystems including air, surface water, groundwater, wastewater, soil, sediment, and marine environments. Some organic compounds, despite their industrial values, are toxic to living organisms and pose significant health risks to humans and wildlife. Detection and monitoring of these organic pollutants in environmental matrices therefore is of great interest and need for remediation and health risk assessment. Although these detections have traditionally been performed using analytical chemical approaches that offer highly sensitive and specific identification of target compounds, these methods require specialized equipment and trained operators, and fail to describe potential bioavailable effects on living organisms. Alternatively, the integration of bioluminescent systems into whole-cell bioreporters presents a new capacity for organic compound detection. These bioreporters are constructed by incorporating reporter genes into catabolic or signaling pathways that are present within living cells and emit a bioluminescent signal that can be detected upon exposure to target chemicals. Although relatively less specific compared to analytical methods, bioluminescent bioassays are more cost-effective, more rapid, can be scaled to higher throughput, and can be designed to report not only the presence but also the bioavailability of target substances. This chapter reviews available bacterial and eukaryotic whole-cell bioreporters for sensing organic pollutants and their applications in a variety of sample matrices. PMID:25084996

  11. Black Nitrogen or Plant-Derived Organic Nitrogen - which Form is More Efficiently Sequestered in Soils?

    NASA Astrophysics Data System (ADS)

    López-Martín, María; Velasco-Molina, Marta; Knicker, Heike

    2014-05-01

    and approached those of the pots with fresh grass litter supporting the mobilization of black nitrogen and its uptake by plants. Our results point to the suggestion that N in PyOM and humified SOM have comparable biochemical stability. In order to test this hypothesis, a further experiment was set up mixtures of soil and humified 15N grass residues or aged 15N grass char to which fresh PyOM or fresh grass residues, respectively, were added. In addition solid-state 15N NMR spectroscopy was applied to disclose the nature of the sequestered N. REFERENCES Knicker, H., Almendros, G., González-Vila, F.J., Martín, F., Lüdemann, H.-D., 1996. 13C- and 15N-NMR spectroscopic examination of the transformation of organic nitrogen in plant biomass during thermal treatment. Soil Biology and Biochemistry, 28, 1053-1060.

  12. ANALYSIS OF ORGANOSILICON COMPOUNDS IV SEPARATION AND DETERMINATION OF METHYLVINYL-CHLOROSILANES AND VINYLCHLOROSILANES BY GAS CHROMOTOGRAPHY (ANALYSE VON ORGANOSILICIUM-VERBINDUNGEN IV. TRENNUNG UND BESTEMMUNG VON METHYLVINYLCHLORSILANEN UND VINYLCHLORSILANEN MITTELS),

    DTIC Science & Technology

    GAS CHROMATOGRAPHY), (*SILICON COMPOUNDS, SEPARATION, ORGANIC COMPOUNDS, SILANES, CHEMICAL ANALYSIS, THERMAL CONDUCTIVITY, NITROGEN, RECORDING SYSTEMS, IDENTIFICATION, VOLUMETRIC ANALYSIS, DISTILLATION, CZECHOSLOVAKIA.

  13. Organic and Inorganic Nitrogen Amendments to Soil as Nematode Suppressants

    PubMed Central

    Rodríguez-Kábana, R.

    1986-01-01

    Inorganic fertilizers containing ammoniacal nitrogen or formulations releasing this form of N in the soil are most effective for suppressing nematode populations. Anhydrous ammonia has been shown to reduce soil populations of Tylenchorhynchus claytoni, Helicotylenchus dihystera, and Heterodera glycines. The rates required to obtain significant suppression of nematode populations are generally in excess of 150 kg N/ha. Urea also suppresses several nematode species, including Meloidogyne spp., when applied at rates above 300 kg N/ha. Additional available carbon must be provided with urea to permit soil microorganisms to metabolize excess N and avoid phytotoxic effects. There is a direct relation between the amount of "protein" N in organic amendments and their effectiveness as nematode population suppressants. Most nematicidal amendments are oil cakes, or animal excrements containing 2-7% (w:w) N; these materials are effective at rates of 4-10 t/ha. Organic soil amendments containing mucopolysaccharides (e.g., mycelial wastes, chitinous matter) are also effective nematode suppressants. PMID:19294153

  14. Effects of halogenated aromatics/aliphatics and nitrogen(N)-heterocyclic aromatics on estimating the persistence of future pharmaceutical compounds using a modified QSAR model.

    PubMed

    Lim, Seung Joo; Fox, Peter

    2014-02-01

    The effects of halogenated aromatics/aliphatics and nitrogen(N)-heterocyclic aromatics on estimating the persistence of future pharmaceutical compounds were investigated using a modified half life equation. The potential future pharmaceutical compounds investigated were approximately 2000 pharmaceutical drugs currently undergoing the United States Food and Drug Administration (US FDA) testing. EPI Suite (BIOWIN) model estimates the fates of compounds based on the biodegradability under aerobic conditions. While BIOWIN considered the biodegradability of a compound only, the half life equation used in this study was modified by biodegradability, sorption and cometabolic oxidation. It was possible that the potential future pharmaceutical compounds were more accurately estimated using the modified half life equation. The modified half life equation considered sorption and cometabolic oxidation of halogenated aromatic/aliphatics and nitrogen(N)-heterocyclic aromatics in the sub-surface, while EPI Suite (BIOWIN) did not. Halogenated aliphatics in chemicals were more persistent than halogenated aromatics in the sub-surface. In addition, in the sub-surface environment, the fates of organic chemicals were much more affected by halogenation in chemicals than by nitrogen(N)-heterocyclic aromatics.

  15. Humic substances and nitrogen-containing compounds from low rank brown coals

    SciTech Connect

    Demirbas, A.; Kar, Y.; Deveci, H.

    2006-03-15

    Coal is one of the sources of nitrogen-containing compounds (NCCs). Recovery of NCCs from brown coals in high yield was carried out from tars of stepwise semicoking of brown coals. Humic acids have been shown to contain many types of nitrogen compounds. Humic acids are thought to be complex aromatic macromolecules with amino acids, amino sugars, peptides, and aliphatic compounds that are involved in the linkages between the aromatic groups. Humic acids extracted from peats, brown coals, and lignites, are characterized using different techniques. Humic substances (HSs) have several known benefits to agriculture. The properties of humic substances vary from source to source, because they are heterogeneous mixtures of biochemical degradation products from plant and animal residues, and synthesis activities of microorganisms. HSs have been considered to be a significant floculant in surface water filtration plants for the production of drinking water as well as the processing of water. HSs are produced from chemical and biological degradation of plant and animal residues and from synthetic activities of microorganisms.

  16. Ammoxidation of Lignocellulosic Materials: Formation of Nonheterocyclic Nitrogenous Compounds from Monosaccharides

    PubMed Central

    2013-01-01

    Ammoxidized technical lignins are valuable soil-improving materials that share many similarities with native terrestrial humic substances. In contrast to lignins, the chemical fate of carbohydrates as typical minor constituents of technical lignins during the ammoxidation processes has not been thoroughly investigated. Recently, we reported the formation of N-heterocyclic, ecotoxic compounds (OECD test 201) from both monosaccharides (d-glucose, d-xylose) and polysaccharides (cellulose, xylan) under ammoxidation conditions and showed that monosaccharides are a source more critical than polysaccharides in this respect. GC/MS-derivatization analysis of the crude product mixtures revealed that ammoxidation of carbohydrates which resembles the conditions encountered in nonenzymatical browning of foodstuff affords also a multitude of nonheterocyclic nitrogenous compounds such as aminosugars, glycosylamines, ammonium salts of aldonic, deoxyaldonic, oxalic and carbaminic acids, urea, acetamide, α-hydroxyamides, and even minor amounts of α-amino acids. d-Glucose and d-xylose afforded largely similar product patterns which differed from each other only for those products that were formed under preservation of the chain integrity and stereoconfiguration of the respective monosaccharide. The kinetics and reaction pathways involved in the formation of the different classes of nitrogenous compounds under ammoxidation conditions are discussed. PMID:23967905

  17. Ammoxidation of lignocellulosic materials: formation of nonheterocyclic nitrogenous compounds from monosaccharides.

    PubMed

    Klinger, Karl Michael; Liebner, Falk; Hosoya, Takashi; Potthast, Antje; Rosenau, Thomas

    2013-09-25

    Ammoxidized technical lignins are valuable soil-improving materials that share many similarities with native terrestrial humic substances. In contrast to lignins, the chemical fate of carbohydrates as typical minor constituents of technical lignins during the ammoxidation processes has not been thoroughly investigated. Recently, we reported the formation of N-heterocyclic, ecotoxic compounds (OECD test 201) from both monosaccharides (D-glucose, D-xylose) and polysaccharides (cellulose, xylan) under ammoxidation conditions and showed that monosaccharides are a source more critical than polysaccharides in this respect. GC/MS-derivatization analysis of the crude product mixtures revealed that ammoxidation of carbohydrates which resembles the conditions encountered in nonenzymatical browning of foodstuff affords also a multitude of nonheterocyclic nitrogenous compounds such as aminosugars, glycosylamines, ammonium salts of aldonic, deoxyaldonic, oxalic and carbaminic acids, urea, acetamide, α-hydroxyamides, and even minor amounts of α-amino acids. D-glucose and D-xylose afforded largely similar product patterns which differed from each other only for those products that were formed under preservation of the chain integrity and stereoconfiguration of the respective monosaccharide. The kinetics and reaction pathways involved in the formation of the different classes of nitrogenous compounds under ammoxidation conditions are discussed.

  18. An advanced technique for speciation of organic nitrogen in atmospheric aerosols

    NASA Astrophysics Data System (ADS)

    Samy, S.; Robinson, J.; Hays, M. D.

    2011-12-01

    The chemical composition of organic nitrogen (ON) in the environment is a research topic of broad significance. The topic intersects the branches of atmospheric, aquatic, and ecological science; thus, a variety of instrumentation, analytical methods, and data interpretation tools have evolved for determination of ON. Recent studies that focus on atmospheric particulate nitrogen (N) suggest a significant fraction (20-80%) of total N is bound in organic compounds. The sources, bioavailability and transport mechanisms of these N-containing compounds can differ, producing a variety of environmental consequences. Amino acids (AA) are a key class of atmospheric ON compounds that can contribute to secondary organic aerosol (SOA) formation and potentially influence water cycles, air pollutant scavenging, and the radiation balance. AA are water-soluble organic compounds (WSOC) that can significantly alter the acid-base chemistry of aerosols, and may explain the buffering capacity that impacts heterogeneous atmospheric chemistry. The chemical transformations that N-containing organic compounds (including AA) undergo can increase the light-absorbing capacity of atmospheric carbon via formation of 'brown carbon'. Suggested sources of atmospheric AA include: marine surface layer transport from bursting sea bubbles, the suspension of bacteria, fungi, algae, pollen, spores, or biomass burning. Methodology for detection of native (underivatized) amino acids (AA) in atmospheric aerosols has been developed and validated (Samy et al., 2011). This presentation describes the use of LC-MS (Q-TOF) and microwave-assisted gas phase hydrolysis for detection of free and combined amino acids in aerosols collected in a Southeastern U.S. forest environment. Accurate mass detection and the addition of isotopically labeled surrogates prior to sample preparation allows for sensitive quantitation of target AA in a complex aerosol matrix. A total of 16 native AA were detected above the reporting

  19. Organic and inorganic nitrogen dynamics in soil - advanced Ntrace approach

    NASA Astrophysics Data System (ADS)

    Andresen, Louise C.; Björsne, Anna-Karin; Bodé, Samuel; Klemedtsson, Leif; Boeckx, Pascal; Rütting, Tobias

    2016-04-01

    Depolymerization of soil organic nitrogen (SON) into monomers (e.g. amino acids) is currently thought to be the rate limiting step for the terrestrial nitrogen (N) cycle. The production of free amino acids (AA) is followed by AA mineralization to ammonium, which is an important fraction of the total N mineralization. Accurate assessment of depolymerization and AA mineralization rate is important for a better understanding of the rate limiting steps. Recent developments in the 15N pool dilution techniques, based on 15N labelling of AA's, allow quantifying gross rates of SON depolymerization and AA mineralization (Wanek et al., 2010; Andersen et al., 2015) in addition to gross N mineralization. However, it is well known that the 15N pool dilution approach has limitations; in particular that gross rates of consumption processes (e.g. AA mineralization) are overestimated. This has consequences for evaluating the rate limiting step of the N cycle, as well as for estimating the nitrogen use efficiency (NUE). Here we present a novel 15N tracing approach, which combines 15N-AA labelling with an advanced version of the 15N tracing model Ntrace (Müller et al., 2007) explicitly accounting for AA turnover in soil. This approach (1) provides a more robust quantification of gross depolymerization and AA mineralization and (2) suggests a more realistic estimate for the microbial NUE of amino acids. Advantages of the new 15N tracing approach will be discussed and further improvements will be identified. References: Andresen, L.C., Bodé, S., Tietema, A., Boeckx, P., and Rütting, T.: Amino acid and N mineralization dynamics in heathland soil after long-term warming and repetitive drought, SOIL, 1, 341-349, 2015. Müller, C., Rütting, T., Kattge, J., Laughlin, R. J., and Stevens, R. J.: Estimation of parameters in complex 15N tracing models via Monte Carlo sampling, Soil Biology & Biochemistry, 39, 715-726, 2007. Wanek, W., Mooshammer, M., Blöchl, A., Hanreich, A., and Richter

  20. Removal of organic pollutants by surfactant modified zeolite: comparison between ionizable phenolic compounds and non-ionizable organic compounds.

    PubMed

    Xie, Jie; Meng, Wenna; Wu, Deyi; Zhang, Zhenjia; Kong, Hainan

    2012-09-15

    The aim of this study was to examine the adsorption capability and mechanism of hexadecyltrimethylammonium modified zeolite, which was synthesized from coal fly ash, for the removal of ionizable phenolic compounds (phenol, p-chlorophenol and bisphenol A, with different pK(a)) and non-ionizable organic compounds (aniline, nitrobenzene, and naphthalene, with different hydrophobicity). The obtained zeolite was identified as type Na-P1 (Na(6)Al(6)Si(10)O(32)·12H(2)O, JCPDS code 39-0219), which is classified into the gismondine group with a pore size of 3.1 Å × 4.5 Å [100] and 2.8 Å × 4.8 Å [101]. The adsorption of the two kinds of organic compounds was due to loaded surfactant bilayer because modified zeolite showed great ability for the removal of organic chemicals while little adsorption by zeolite was observed. The isotherm data of ionizable compounds fitted well to the Langmuir model but those of non-ionizable chemicals followed a linear equation. Uptake of ionizable compounds depended greatly on pH, increasing at alkaline pH conditions. In contrary, adsorption of non-ionizable chemicals was essentially the same at all pH levels studied. The adsorption of both kinds of organic compounds correlated well to k(ow) value, suggesting that more hydrophobic organic contaminants are more easily retained by modified zeolite. Based on the different adsorption behavior, the uptake of non-ionizable pollutants was thought to be a single partitioning process into the surfactant bilayer. For ionizable compounds, however, interaction of the phenol group(s) with the positively charged "head" of surfactant additionally functions.

  1. Chemical reactions of organic compounds on clay surfaces.

    PubMed Central

    Soma, Y; Soma, M

    1989-01-01

    Chemical reactions of organic compounds including pesticides at the interlayer and exterior surfaces of clay minerals and with soil organic matter are reviewed. Representative reactions under moderate conditions possibly occurring in natural soils are described. Attempts have been made to clarify the importance of the chemical nature of molecules, their structures and their functional groups, and the Brönsted or Lewis acidity of clay minerals. PMID:2533556

  2. The photostabililty of prebiotic organic compounds on cometary dusts.

    NASA Astrophysics Data System (ADS)

    Saiagh, K.; Aleian, A.; Fray, N.; Cloix, M.; Cottin, H.

    2013-09-01

    A new methodology for measuring the photostability of organic compounds in extraterrestrial environments will be presented. It is based on Low Earth Orbit (LEO) and "classical" laboratory photolysis experiments, as well as on quantitative measurements of the VUV/UV ( < 300 nm) absorption cross section spectra. We will discuss the complementarily and limits of each approach, and discuss the astrobiological relevance of such studies in the frame of the importation of organic matter to Earth via micrometeorites.

  3. Biotic and Abiotic Attenuation of Nitrogenous Energetic Compounds (NEC) in Coastal Waters and Sediments

    DTIC Science & Technology

    2006-05-30

    B.J., Steele, J.K., and T.J. Boyd. 2002. Transport, deposition and biodegradation of particle bound polycyclic aromatic hydrocarbons in a tidal basin...deficient of organic nitrogen sources but rich in polycyclic aromatic hydrocarbons (PAHs) and polychlorinated biphenyls (PCBs). This facultative anaerobe was...detonations on primary production may be transient. Work on NEC biodegradation by bacteria (Task 4) involved surveys of the TNT, 2,4- 3

  4. Evaluation of organic compounds and trace elements in Amazon Creek Basin, Oregon, September 1990

    USGS Publications Warehouse

    Rinella, F.A.

    1993-01-01

    Water and bottom sediment were collected from Amazon Creek, Oregon during a summer low-flow condition and analyzed for different classes of organic compounds, including many from the U.S. Environmental Protection Agency's priority pollutant list. Bottom sediment also was analyzed for trace elements typically associated with urban runoff. Trace-element concentrations in the less than 63 micrometer fraction of Amazon Creek bottom-sediment samples were compared with baseline concentrations (expected 95 percent confidence range) for soils from the Western United States and with concen- trations found in bottom sediment from the Willamette River Basin. Total-digestion concentrations of antimony, arsenic, cadmium, chromium, cobalt, copper, lead, manganese, mercury, nickel, silver, titanium, and zinc were enriched at some or all sites sampled. Whole-water samples from some sites contained concentrations of several chlorophenoxy-acid herbicides, the organophosphorus insecticide diazinon, and several semivolatile priority pollutants. Classes of compounds not detected in whole-water samples included carbamate insecticides, triazine and other nitrogen-containing herbicides, and purgeable organic compounds. Bottom-sediment samples contained many organochlorine compounds, including chlordane, DDT plus metabolites, dieldrin, endrin, heptachlor epoxide (a metabolite of heptachlor), and PCBs at some or all sites sampled. Twenty-four of 54 semivolatile compounds were detected in bottom- sediment samples at some or all sites sampled.

  5. Non-targeted analyses of organic compounds in urban wastewater.

    PubMed

    Alves Filho, Elenilson G; Sartori, Luci; Silva, Lorena M A; Silva, Bianca F; Fadini, Pedro S; Soong, Ronald; Simpson, Andre; Ferreira, Antonio G

    2015-09-01

    A large number of organic pollutants that cause damage to the ecosystem and threaten human health are transported to wastewater treatment plants (WWTPs). The problems regarding water pollution in Latin America have been well documented, and there is no evidence of substantive efforts to change the situation. In the present work, two methods to study wastewater samples are employed: non-targeted 1D ((13)C and (1)H) and 2D NMR spectroscopic analysis to characterize the largest possible number of compounds from urban wastewater and analysis by HPLC-(UV/MS)-SPE-ASS-NMR to detect non-specific recalcitrant organic compounds in treated wastewater without the use of common standards. The set of data is composed of several compounds with the concentration ranging considerably with treatment and seasonality. An anomalous discharge, the influence of stormwater on the wastewater composition and the presence of recalcitrant compounds (linear alkylbenzene sulfonate surfactant homologs) in the effluent were further identified. The seasonal variations and abnormality in the composition of organic compounds in sewage indicated that the procedure that was employed can be useful in the identification of the pollution source and to enhance the effectiveness of WWTPs in designing preventive action to protect the equipment and preserve the environment.

  6. Key volatile organic compounds emitted from swine nursery house

    NASA Astrophysics Data System (ADS)

    Yao, H. Q.; Choi, H. L.; Zhu, K.; Lee, J. H.

    2011-05-01

    This study was carried out to quantify the concentration and emission levels of key volatile organic compounds (VOCs) - sulfides, indolics, phenolics and volatile fatty acids (VFA) - emitted from swine nursery house, and assess the effect of microclimate (including temperature, relative humidity and air speed) on the key odorous compounds. Samples were collected from the Experimental Farm of Seoul National University in Suwon, South Korea. And the collection took place for four seasons and the sampling time was fixed at 10:30 in the morning. The application of one-way ANOVA and Bonferroni t analyses revealed that, most of the odorous compound concentrations, such as dimethyl sulfide (DMS), dimethyl disulfide (DMDS), indole, p-cresol and all the volatile fatty acids were lowest during the summer ( P < 0.01). Meanwhile, negative correlations were observed between temperature and odorants, as well as air speed and odorants. A possible reason was that high ventilation transferred most of the odors out of the house during the summer. From the whole year data, non-linear multiple regressions were conducted and the equations were proposed depending upon the relationships between microclimate parameters and odorous compounds. The equations were applied in hope of easily calculating the concentrations of the odorous compounds in the commercial farms. The results obtained in this study should be used for reducing the volatile organic compounds by controlling microclimate parameters and also could be helpful in setting a guideline for good management practices in nursery house.

  7. Intake and digestibility in cattle fed low-quality tropical forage and supplemented with nitrogenous compounds.

    PubMed

    Sampaio, Claudia B; Detmann, Edenio; Paulino, Mario F; Valadares Filho, Sebastiao C; de Souza, Marjorrie A; Lazzarini, Isis; Paulino, Pedro V Rodrigues; de Queiroz, Augusto C

    2010-10-01

    The effects of supplementation with nitrogenous compounds on intake, digestibility, and microbial protein synthesis in cattle fed low-quality tropical forage were assessed. Five rumen fistulated crossbred Holstein x Gir heifers were used, with initial average live weight of 180 +/- 21 kg. Signal grass (Brachiaria decumbens) hay (48.6 g kg(-1) of crude protein (CP), on a dry matter (DM) basis) was used as roughage. Five treatments were defined according to nitrogen supplementation level (0, 20, 40, 60, and 80 g of CP kg(-1) above the CP level of the hay). A mixture of urea, ammonium sulfate, and albumin at the ratios of 4.5:0.5:1.0, respectively, was used as nitrogen source. The experiment consisted of five experimental periods, according to a 5 x 5 Latin square design. The average CP contents in the diets were 51.9, 71.1, 86.0, 116.7, and 130.2 g kg(-1), on a DM basis. A quadratic effect was detected (P < 0.10) of the CP levels in the diets on DM and neutral detergent fiber intake (kg/day), with maximum response at the levels of 102.4 and 100.5 g CP kg(-1) DM, respectively. The average daily concentration of rumen ammonia nitrogen showed increasing linear pattern (P < 0.01) as function of CP levels in the diet, with estimated value of 9.64 mg dL(-1) equivalent to the maximum DM intake. Microbial nitrogen flow in the intestine was linearly and positively related (P < 0.01) with the CP levels in the diet.

  8. Biogeochemical toxicity and phytotoxicity of nitrogenous compounds in a variety of arctic soils.

    PubMed

    Anaka, Alison; Wickstrom, Mark; Siciliano, Steven D

    2008-08-01

    Ammonium nitrate (NH(4)NO(3)) is a common water pollutant associated with many industrial and municipal activities. One solution to reduce exposure of sensitive aquatic systems to nitrogenous compounds is to atomize (atmospherically disperse in fine particles) contaminated water over the Arctic tundra, which will reduce nitrogen loading to surface water. The toxicity of ammonium nitrate to Arctic soils, however, is poorly understood. In the present study, we characterized the biogeochemical toxicity and phytotoxicity of ammonium nitrate solutions in four different Arctic soils and in a temperate soil. Soil was exposed to a range of ammonium nitrate concentrations over a 90-d period. Dose responses of carbon mineralization, nitrification, and phytotoxicity endpoints were estimated. In addition to direct toxicity, the effect of ammonium nitrate on ecosystem resilience was investigated by dosing nitrogen-impacted soils with boric acid. Ammonium nitrate had no effect on carbon mineralization activity and only affected nitrification in one soil, a polar desert soil from Cornwallis Island, Northwest Territories, Canada. In contrast, ammonium nitrate applications (43 mmol N/L soil water) significantly impaired seedling emergence, root length, and shoot length of northern wheatgrass (Elymus lanceolatus). Concentrations of ammonium nitrate in soil water that inhibited plant parameters by 20% varied between 43 and 280 mmol N/L soil water, which corresponds to 2,100 to 15,801 mg/L of ammonium nitrate in the application water. Arctic soils were more resistant to ammonium nitrate toxicity compared with the temperate soil under these study conditions. It is not clear, however, if this represents a general trend for all polar soils, and because nitrogen is an essential macronutrient, nitrogenous toxicity likely should be considered as a special case for soil toxicity.

  9. Analysis of Organic Compounds in Mars Analog Samples

    NASA Technical Reports Server (NTRS)

    Mahaffy, P. R.; Brinckerhoff, W. B.; Buch, A.; Cabane, M.; Coll, P.; Demick, J.; Glavin, D. P.

    2004-01-01

    The detailed characterization of organic compounds that might be preserved in rocks, ices, or sedimentary layers on Mars would be a significant step toward resolving the question of the habitability and potential for life on that planet. The fact that the Viking gas chromatograph mass spectrometer (GCMS) did not detect organic compounds should not discourage further investigations since (a) an oxidizing environment in the near surface fines analyzed by Viking is likely to have destroyed many reduced carbon species; (b) there are classes of refractory or partially oxidized species such as carboxylic acids that would not have been detected by the Viking GCMS; and (c) the Viking landing sites are not representative of Mars overall. These factors motivate the development of advanced in situ analytical protocols to carry out a comprehensive survey of organic compounds in martian regolith, ices, and rocks. We combine pyrolysis GCMS for analysis of volatile species, chemical derivatization for transformation of less volatile organics, and laser desorption mass spectrometry (LDMS) for analysis of elements and more refractory, higher-mass organics. To evaluate this approach and enable a comparison with other measurement techniques we analyze organics in Mars simulant samples.

  10. Near-Roadway Emission of Reactive Nitrogen Compounds and Other Non-Criteria Pollutants at a Southern California Freeway Site

    NASA Astrophysics Data System (ADS)

    Moss, J. A.; Baum, M.; Castonguay, A. E.; Aguirre, V., Jr.; Pesta, A.; Fanter, R. K.; Anderson, M.

    2015-12-01

    Emission control systems in light-duty motor vehicles (LDMVs) have played an important role in improving regional air quality by dramatically reducing the concentration of criteria pollutants (carbon monoxide, hydrocarbons, and nitrogen oxides) in exhaust emissions. Unintended side-reactions occurring on the surface of three-way catalysts may lead to emission of a number of non-criteria pollutants whose identity and emission rates are poorly understood. A series of near-roadway field studies conducted between 2009-2015 has investigated LDMV emissions of these pollutants with unprecedented depth of coverage, including reactive nitrogen compounds (NH3, amines, HCN, HONO, and HNO3), organic peroxides, and carbonyl compounds (aldehydes, ketones, and carboxylic acids). Methods to collect these pollutants using mist chambers, annular denuders, impingers, and solid-phase cartridges and quantify their concentration using GC-MS, LC-MS/MS, IC, and colorimetry were developed and validated in the laboratory and field. These methods were subsequently used in near-roadway field studies where the concentrations of the target compounds integrated over 1-4 hour blocks were measured at the edge of a freeway and at a background site 140 m from the roadway. Concentrations followed a steep decreasing gradient from the freeway to the background site. Emission factors (pollutant mass emitted per mass fuel consumed) were calculated by carbon mass balance using the difference in concentration measured between the freeway and background sites for the emitted pollutant and CO2 as a measure of carbon mass in the vehicle exhaust. The significance of these results will be discussed in terms of emissions inventories in the South Coast Air Basin of California, emission trends at this site over the period of 2009-2015, and for NH3, emission measurements conducted by our group and others over the period 2000-2015.

  11. [Experimental evaluation of actoprotective activity of nitrogen-containing heterocyclic compounds derivatives in extreme conditions].

    PubMed

    Tsublova, E G; Ivanova, T G; Ivanova, T N; Iasnetsov, V V

    2013-07-01

    In experiments on nonlinear male mice the ability of new derivatives of nitrogen-containing heterocyclic compounds to increase the physical working capacity in conditions of hyperthermia, hypothermia and acute normobaric hypoxia and hypercapnia has been investigated. It is established, that pyridine derivative IBHF-11 has more expressed positive action in the said conditions. It provided increase of the working capacity of animals at all kinds of extreme influence, and the value of positive action was comparable, and in conditions of acute normobaric hypoxia and hypercapnia exceeded those at the reference products bemitil and bromantan.

  12. Global inventory of volatile organic compound emissions from anthropogenic sources

    SciTech Connect

    Piccot, S.D.; Watson, J.J.; Jones, J.W.

    1992-01-01

    The paper discusses the development of a global inventory of anthropogenic volatile organic compound (VOC) emissions. It includes VOC estimates for seven classes of VOCs: paraffins, olefins, aromatics (benzene, toluene, xylene), formaldehyde, other aldehydes, other aromatics, and marginally reactive compounds. These classes represent general classes of VOC compounds that possess different chemical reactivities in the atmosphere. The inventory shows total global anthropogenic VOC emissions of about 110,000 Gg/yr, about 10% lower than global VOC inventories developed by other researchers. The study identifies the U.S. as the largest emitter (21% of the total global VOC), followed by the USSR, China, India, and Japan. Globally, fuel wood combustion and savanna burning were among the largest VOC emission sources, accounting for over 35% of the total global VOC emissions. The production and use of gasoline, refuse disposal activities, and organic chemical and rubber manufacturing were also found to be significant sources of global VOC emissions.

  13. Biogenic volatile organic compounds in the Earth system.

    PubMed

    Laothawornkitkul, Jullada; Taylor, Jane E; Paul, Nigel D; Hewitt, C Nicholas

    2009-01-01

    Biogenic volatile organic compounds produced by plants are involved in plant growth, development, reproduction and defence. They also function as communication media within plant communities, between plants and between plants and insects. Because of the high chemical reactivity of many of these compounds, coupled with their large mass emission rates from vegetation into the atmosphere, they have significant effects on the chemical composition and physical characteristics of the atmosphere. Hence, biogenic volatile organic compounds mediate the relationship between the biosphere and the atmosphere. Alteration of this relationship by anthropogenically driven changes to the environment, including global climate change, may perturb these interactions and may lead to adverse and hard-to-predict consequences for the Earth system.

  14. Influence of volatile organic compounds on Fusarium graminearum mycotoxin production

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Volatile organic compounds (VOCs) are involved in a diverse range of ecological interactions. Due to their low molecular weight, lipophilic nature, and high vapor pressure at ambient temperatures, they can serve as airborne signaling molecules that are capable of mediating inter and intraspecies com...

  15. Volatile organic compound emissions from dairy facilities in central California

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Emissions of volatile organic compounds (VOCs) from dairy facilities are thought to be an important contributor to high ozone levels in central California, but emissions inventories from these sources contain significant uncertainties. In this work, VOC emissions were measured at two central Califor...

  16. Modeling emissions of volatile organic compounds from silage

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Photochemical smog is a major air pollution problem and a significant cause of premature death in the U.S. Smog forms in the presence of volatile organic compounds (VOCs), which are emitted primarily from industry and motor vehicles in the U.S. However, dairy farms may be an important source in so...

  17. LEAVES AS INDICATORS OF EXPOSURE TO AIRBORNE VOLATILE ORGANIC COMPOUNDS

    EPA Science Inventory

    The concentration of volatile organic compounds (VOCs) in leaves is primarily a product of airborne exposures and dependent upon bioconcentration factors and release rates. The bioconcentration factors for VOCs in grass are found to be related to their partitioning between octan...

  18. Volatile organic compounds of whole grain soft winter wheat

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The aroma from volatile organic compounds (VOCs) is an indicator of grain soundness and also an important quality attribute of grain foods. To identify the inherent VOCs of wheat grain unaffected by fungal infestation and other extrinsic factors, grains of nine soft wheat varieties were collected at...

  19. Measuring Emissions of Volatile Organic Compounds from Silage

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Volatile organic compound (VOC) emissions are considered to be important precursors to smog and ozone production. An experimental protocol was developed to obtain undisturbed silage samples from silage storages. Samples were placed in a wind tunnel where temperature, humidity, and air flow were cont...

  20. Modeling emissions of volatile organic compounds from silage

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Volatile organic compounds (VOCs), necessary reactants for photochemical smog formation, are emitted from numerous sources. Limited available data suggest that dairy farms emit VOCs with cattle feed, primarily silage, being the primary source. Process-based models of VOC transfer within and from si...

  1. 40 CFR 60.442 - Standard for volatile organic compounds.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 6 2011-07-01 2011-07-01 false Standard for volatile organic compounds. 60.442 Section 60.442 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Pressure Sensitive Tape and Label Surface Coating Operations § 60.442 Standard for volatile...

  2. 40 CFR 60.442 - Standard for volatile organic compounds.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 7 2014-07-01 2014-07-01 false Standard for volatile organic compounds. 60.442 Section 60.442 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Pressure Sensitive Tape and Label Surface Coating Operations § 60.442 Standard for volatile...

  3. Instrument for Analysis of Organic Compounds on Other Planets

    NASA Technical Reports Server (NTRS)

    Daulton, Riley M.; Hintze, Paul E.

    2016-01-01

    The goal of this project is to develop the Instrument for Solvent Extraction and Analysis of Extraterrestrial Bodies using In Situ Resources (ISEE). Specifically, ISEE will extract and characterize organic compounds from regolith which is found on the surface of other planets or asteroids. The techniques this instrument will use are supercritical fluid extraction (SFE) and supercritical fluid chromatography (SFC). ISEE aligns with NASA's goal to expand the frontiers of knowledge, capability, and opportunities in space in addition to supporting NASA's aim to search for life elsewhere by characterizing organic compounds. The outcome of this project will be conceptual designs of 2 components of the ISEE instrument as well as the completion of proof-of-concept extraction experiments to demonstrate the capabilities of SFE. The first conceptual design is a pressure vessel to be used for the extraction of the organic compounds from the regolith. This includes a comparison of different materials, geometry's, and a proposition of how to insert the regolith into the vessel. The second conceptual design identifies commercially available fluid pumps based on the requirements needed to generate supercritical CO2. The proof-of-concept extraction results show the percent mass lost during standard solvent extractions of regolith with organic compounds. This data will be compared to SFE results to demonstrate the capabilities of ISEE's approach.

  4. 40 CFR 60.442 - Standard for volatile organic compounds.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 6 2010-07-01 2010-07-01 false Standard for volatile organic compounds. 60.442 Section 60.442 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Pressure Sensitive Tape and Label Surface Coating Operations § 60.442 Standard for volatile...

  5. 40 CFR 60.442 - Standard for volatile organic compounds.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 7 2013-07-01 2013-07-01 false Standard for volatile organic compounds. 60.442 Section 60.442 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Pressure Sensitive Tape and Label Surface Coating Operations § 60.442 Standard for volatile...

  6. 40 CFR 60.442 - Standard for volatile organic compounds.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 7 2012-07-01 2012-07-01 false Standard for volatile organic compounds. 60.442 Section 60.442 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Pressure Sensitive Tape and Label Surface Coating Operations § 60.442 Standard for volatile...

  7. Qualitative analysis of volatile organic compounds on biochar

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Qualitative identification of sorbed volatile organic compounds (VOCs) on biochar was conducted by headspace thermal desorption coupled to capillary gas chromatographic-mass spectrometry. VOCs may have a mechanistic role influencing plant and microbial responses to biochar amendments, since VOCs ca...

  8. MEASUREMENT OF ORGANIC COMPOUND EMISSIONS USING SMALL TEST CHAMBERS

    EPA Science Inventory

    Organic compounds emitted from a variety of indoor materials have been measured using small (166 L) environmental test chambers. The paper discusses: a) factors to be considered in small chamber testing; b) parameters to be controlled; c) the types of results obtained. The follow...

  9. MICROBIAL VOLATILE ORGANIC COMPOUND EMISSION RATES AND EXPOSURE MODEL

    EPA Science Inventory

    This paper presents the results from a study that examined microbial volatile organic compound (MVOC) emissions from six fungi and one bacterial species (Streptomyces spp.) commonly found in indoor environments. Data are presented on peak emission rates from inoculated agar plate...

  10. The Survival of Meteorite Organic Compounds with Increasing Impact Pressure

    NASA Technical Reports Server (NTRS)

    Cooper, George; Horz, Friedrich; Oleary, Alanna; Chang, Sherwood; DeVincenzi, Donald L. (Technical Monitor)

    2000-01-01

    The majority of carbonaceous meteorites studied today are thought to originate in the asteroid belt. Impacts among asteroidal objects generate heat and pressure that may have altered or destroyed pre-existing organic matter in both targets and projectiles to a greater or lesser degree depending upon impact velocities. Very little is known about the shock related chemical evolution of organic matter relevant to this stage of the cosmic history of biogenic elements and compounds. The present work continues our study of the effects of shock impacts on selected classes of organic compounds utilizing laboratory shock facilities. Our approach was to subject mixtures of organic compounds, embedded in a matrix of the Murchison meteorite, to a simulated hypervelocity impact. The molecular compositions of products were then analyzed to determine the degree of survival of the original compounds. Insofar as results associated with velocities < 8 km/sec may be relevant to impacts on planetary surfaces (e.g., oblique impacts, impacts on small outer planet satellites) or grain-grain collisions in the interstellar medium, then our experiments will be applicable to these environments as well.

  11. SOIL NITROGEN TRANSFORMATIONS AND ROLE OF LIGHT FRACTION ORGANIC MATTER IN FOREST SOILS

    EPA Science Inventory

    Depletion of soil organic matter through cultivation may alter substrate availability for microbes, altering the dynamic balance between nitrogen (N) immobilization and mineralization. Soil light fraction (LF) organic matter is an active pool that decreases upon cultivation, and...

  12. Association of nitrogen compounds in drinking water with incidence of esophageal squamous cell carcinoma in Shexian, China.

    PubMed

    Zhang, Nan; Yu, Cao; Wen, Denggui; Chen, Jun; Ling, Yiwei; Terajima, Kenshi; Akazawa, Kohei; Shan, Baoen; Wang, Shijie

    2012-01-01

    The incidence of esophageal squamous cell carcinoma (ESCC), which is the eighth most common malignancy worldwide, is highest in China. The purpose of this study was to investigate the association between nitrogen compounds in drinking water with the incidence of ESCC by geographical spatial analysis. The incidence of ESCC is high in Shexian county, China, and environmental factors, particularly nitrogen-contaminated drinking water, are the main suspected risk factors. This study focuses on three nitrogen compounds in drinking water, namely, nitrates, nitrites, and ammonia, all of which are derived mainly from domestic garbage and agricultural fertilizer. The study surveyed 48 villages in the Shexian area with a total population of 54,716 (661 adults with ESCC and 54,055 non-cancer subjects). Hot-spot analysis was used to identify spatial clusters with a high incidence of ESCC and a high concentration of nitrogen compounds. Logistic regression analysis was used to detect risk factors for ESCC incidence. Most areas with high concentrations of nitrate nitrogen in drinking water had a high incidence of ESCC. Correlation analysis revealed a significant positive relationship between nitrate concentration and ESCC (P = 0.01). Logistic regression analysis also confirmed that nitrate nitrogen has a significantly higher odds ratio. The results indicate that nitrate nitrogen is associated with ESCC incidence in Shexian county. In conclusion, high concentrations of nitrate nitrogen in drinking water may be a significant risk factor for the incidence of ESCC.

  13. [Binding of Volatile Organic Compounds to Edible Biopolymers].

    PubMed

    Misharina, T A; Terenina, M B; Krikunova, N I; Medvedeva, I B

    2016-01-01

    Capillary gas chromatography was used to study the influence of the composition and structure of different edible polymers (polysaccharides, vegetable fibers, and animal protein gelatin) on the binding of essential oil components. The retention of volatile organic compounds on biopolymers was shown to depend on their molecule structure and the presence, type, and position of a functional group. The maximum extent of the binding was observed for nonpolar terpene and sesquiterpene hydrocarbons, and the minimum extent was observed for alcohols. The components of essential oils were adsorbed due mostly to hydrophobic interactions. It was shown that the composition and structure of a compound, its physico-chemical state, and the presence of functional groups influence the binding. Gum arabic and guar gum were found to bind nonpolar compounds to a maximum and minimum extent, respectively. It was demonstrated the minimum adsorption ability of locust bean gum with respect to all studied compounds.

  14. Structuring of bacterioplankton communities by specific dissolved organic carbon compounds.

    PubMed

    Gómez-Consarnau, Laura; Lindh, Markus V; Gasol, Josep M; Pinhassi, Jarone

    2012-09-01

    The main role of microorganisms in the cycling of the bulk dissolved organic carbon pool in the ocean is well established. Nevertheless, it remains unclear if particular bacteria preferentially utilize specific carbon compounds and whether such compounds have the potential to shape bacterial community composition. Enrichment experiments in the Mediterranean Sea, Baltic Sea and the North Sea (Skagerrak) showed that different low-molecular-weight organic compounds, with a proven importance for the growth of marine bacteria (e.g. amino acids, glucose, dimethylsulphoniopropionate, acetate or pyruvate), in most cases differentially stimulated bacterial growth. Denaturing gradient gel electrophoresis 'fingerprints' and 16S rRNA gene sequencing revealed that some bacterial phylotypes that became abundant were highly specific to enrichment with specific carbon compounds (e.g. Acinetobacter sp. B1-A3 with acetate or Psychromonas sp. B3-U1 with glucose). In contrast, other phylotypes increased in relative abundance in response to enrichment with several, or all, of the investigated carbon compounds (e.g. Neptuniibacter sp. M2-A4 with acetate, pyruvate and dimethylsulphoniopropionate, and Thalassobacter sp. M3-A3 with pyruvate and amino acids). Furthermore, different carbon compounds triggered the development of unique combinations of dominant phylotypes in several of the experiments. These results suggest that bacteria differ substantially in their abilities to utilize specific carbon compounds, with some bacteria being specialists and others having a more generalist strategy. Thus, changes in the supply or composition of the dissolved organic carbon pool can act as selective forces structuring bacterioplankton communities.

  15. Bioavailable and biodegradable dissolved organic nitrogen in activated sludge and trickling filter wastewater treatment plants

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A study was carried out to understand the fate of biodegradable dissolved organic nitrogen (BDON) and bioavailable dissolved organic nitrogen (ABDON) along the treatment trains of a wastewater treatment facility (WWTF) equipped with an activated sludge (AS) system and a WWTF equipped with a two-stag...

  16. Polybenzimidazole compounds

    DOEpatents

    Klaehn, John R.; Peterson, Eric S.; Wertsching, Alan K.; Orme, Christopher J.; Luther, Thomas A.; Jones, Michael G.

    2010-08-10

    A PBI compound that includes imidazole nitrogens, at least a portion of which are substituted with an organic-inorganic hybrid moiety. At least 85% of the imidazole nitrogens may be substituted. The organic-inorganic hybrid moiety may be an organosilane moiety, for example, (R)Me.sub.2SiCH.sub.2--, where R is selected from among methyl, phenyl, vinyl, and allyl. The PBI compound may exhibit similar thermal properties in comparison to the unsubstituted PBI. The PBI compound may exhibit a solubility in an organic solvent greater than the solubility of the unsubstituted PBI. The PBI compound may be included in separatory media. A substituted PBI synthesis method may include providing a parent PBI in a less than 5 wt % solvent solution. Substituting may occur at about room temperature and/or at about atmospheric pressure. Substituting may use at least five equivalents in relation to the imidazole nitrogens to be substituted or, preferably, about fifteen equivalents.

  17. Detection and Quantification of Nitrogen Compounds in Martian Solid Samples by the Sample Analysis at Mars (SAM) Instrument Suite

    NASA Technical Reports Server (NTRS)

    Stern, Jennifer C.; Navarro-Gonzalez, Rafael; Freissinet, Caroline; McKay, Christopher P.; Archer, Paul Douglas; Buch, Arnaud; Eigenbrode, Jennifer L.; Franz, Heather; Glavin, Daniel Patrick; Ming, Douglas W/; Steele, Andrew; Szopa, Cyril; Wray, James J.; Conrad, Pamela Gales; Mahaffay, Paul R.

    2013-01-01

    The Sample Analysis at Mars (SAM) instrument suite on the Mars Science Laboratory (MSL) Curiosity Rover detected both reduced and oxidized nitrogen-bearing compounds during the pyrolysis of surface materials from three sites at Gale Crater. Preliminary detections of nitrogen species include NO, HCN, ClCN, CH3CN, and TFMA (trifluoro-Nmethyl-acetamide). On Earth, nitrogen is a crucial bio-element, and nitrogen availability controls productivity in many environments. Nitrogen has also recently been detected in the form of CN in inclusions in the Martian meteorite Tissint, and isotopically heavy nitrogen (delta N-15 approx +100per mille) has been measured during stepped combustion experiments in several SNC meteorites. The detection of nitrogen-bearing compounds in Martian regolith would have important implications for the habitability of ancient Mars. However, confirmation of indigenous Martian nitrogen bearing compounds will require ruling out their formation from the terrestrial derivatization reagents (e.g. N-methyl-N-tert-butyldimethylsilyl-trifluoroacetamide, MTBSTFA and dimethylformamide, DMF) carried for SAM's wet chemistry experiment that contribute to the SAM background. The nitrogen species we detect in the SAM solid sample analyses can also be produced during laboratory pyrolysis experiments where these reagents are heated in the presence of perchlorate, a compound that has also been identified by SAM in Mars solid samples. However, this does not preclude a Martian origin for some of these compounds, which are present in nanomolar concentrations in SAM evolved gas analyses. Analysis of SAM data and laboratory breadboard tests are underway to determine whether nitrogen species are present at higher concentrations than can be accounted for by maximum estimates of nitrogen contribution from MTBSTFA and DMF. In addition, methods are currently being developed to use GC Column 6, (functionally similar to a commercial Q-Bond column), to separate and identify

  18. Diagnostics of organic compounds in water quality monitoring

    SciTech Connect

    Poryvkina, L.; Leeben, A.

    1997-08-01

    The application of two-dimensional fluorescent technique for automatic monitoring of organic compounds in a water is discussed. For recognition and quantitative estimation of water organics the spectra were systematized and arranged into the calibrated catalogues of spectral signatures. The catalogue compilation and training of expert system for diagnostics of natural organics, oils and chemical pollution are considered. The two-dimensional fluorescent method was applied for the investigation of the environmental effects of the power plants on the river`s water in the north area of Estonia.

  19. Analysis of organic compounds in returned comet nucleus samples

    NASA Technical Reports Server (NTRS)

    Cronin, J. R.

    1989-01-01

    Techniques for analysis of organic compounds in returned comet nucleus samples are described. Interstellar, chondritic and transitional organic components are discussed. Appropriate sampling procedures will be essential to the success of these analyses. It will be necessary to return samples that represent all the various regimes found in the nucleus, e.g., a complete core, volatile components (deep interior), and crustal components (surface minerals, rocks, processed organics such as macromolecular carbon and polymers). Furthermore, sampling, storage, return, and distribution of samples must be done under conditions that preclude contamination of the samples by terrestrial matter.

  20. Emission of volatile organic compounds from silage: compounds, sources, and implications

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Silage, fermented cattle feed, has recently been identified as a significant source of volatile organic compounds (VOCs) emitted to the atmosphere. A small number of studies have measured VOC emission from silage, but not enough is known about the processes involved to accurately quantify emission r...

  1. Determination of fluorine in organic compounds: Microcombustion method

    USGS Publications Warehouse

    Clark, H.S.

    1951-01-01

    A reliable and widely applicable means of determining fluorine in organic compounds has long been needed. Increased interest in this field of research in recent years has intensified the need. Fluorine in organic combinations may be determined by combustion at 900?? C. in a quartz tube with a platinum catalyst, followed by an acid-base titration of the combustion products. Certain necessary precautions and known limitations are discussed in some detail. Milligram samples suffice, and the accuracy of the method is about that usually associated with the other halogen determinations. Use of this method has facilitated the work upon organic fluorine compounds in this laboratory and it should prove to be equally valuable to others.

  2. Measurements of Halogenated Organic Compounds near the Tropical Tropopause

    NASA Technical Reports Server (NTRS)

    Schauffler, S. M.; Heidt, L. E.; Pollock, W. H.; Gilpin, T. M.; Vedder, J. F.; Solomon, S.; Leub, R. A.; Atlas, E. L.

    1993-01-01

    The amount of organic chlorine and bromine entering the stratosphere have a direct influence on the magnitude of chlorine and bromine catalyzed ozone losses. Twelve organic chlorine species and five organic bromine species were measured from 12 samples collected near the tropopause between 23.8 deg N and 25.3 deg N during AASE 2. The average mixing ratios of total organic chlorine and total organic bromine were 3.50 +/- 0.06 ppbv and 21.1 +/- 0.8 pptv, respectively. CH3Cl represented 15.1% of the total organic chlorine, with CFC 11 (CCl3F) and CFC 12 (CCl2F2) accounting for 22.6% and 28.2%, respectively, with the remaining 34.1% primarily from CCl4, CH3CCl3, and CFC 113 (CCl2FCClF2). CH3Br represented 54% of the total organic bromine. The 95% confidence intervals of the mixing ratios of all but four of the individual compounds were within the range observed in low and mid-latitude midtroposphere samples. The four compounds with significantly lower mixing ratios at the tropopause were CHCl3, CH2Cl2, CH2Br2, and CH3CCl3. The lower mixing ratios may be due to entrainment of southern hemisphere air during vertical transport in the tropical region and/or to exchange of air across the tropopause between the lower stratosphere and upper troposphere.

  3. Measurements of halogenated organic compounds near the tropical tropopause

    NASA Technical Reports Server (NTRS)

    Schauffler, S. M.; Heidt, L. E.; Pollock, W. H.; Gilpin, T. M.; Vedder, J. F.; Solomon, S.; Lueb, R. A.; Atlas, E. L.

    1993-01-01

    The amount of organic chlorine and bromine entering the stratosphere have a direct influence on the magnitude of chlorine and bromine catalyzed ozone losses. Twelve organic chlorine species and five organic bromine species were measured from 12 samples collected near the tropopause between 23.8 deg N and 25.3 deg N during AASE 2. The average mixing ratios of total organic chlorine and total organic bromine were 3.50 +/- 0.06 ppbv and 21.1 +/- 0.8 pptv, respectively. CH3Cl represented 15.1% of the total organic chlorine, with CFC 11 (CCl3F) and CFC 12 (CCl2F2) accounting for 22.6% and 28.2%, respectively, with the remaining 34.1% primarily from CCl4, CH3CCl3, and CFC 113 (CCl2FCClF2). CH3Br represented 54% of the total organic bromine. The 95% confidence intervals of the mixing ratios of all but four of the individual compounds were within the range observed in low and mid-latitude mid-troposphere samples. The four compounds with significantly lower mixing ratios at the tropopause were CHCl3, CH2Cl2, CH2Br2, and CH3CCl3. The lower mixing ratios may be due to entrainment of southern hemisphere air during vertical transport in the tropical region and/or to exchange of air across the tropopause between the lower stratosphere and upper troposphere.

  4. Flame retardant finishing of cotton fabric based on synergistic compounds containing boron and nitrogen.

    PubMed

    Xie, Kongliang; Gao, Aiqin; Zhang, Yongsheng

    2013-10-15

    Boric acid and compound containing nitrogen, 2,4,6-tri[(2-hydroxy-3-trimethyl-ammonium)propyl]-1,3,5-triazine chloride (Tri-HTAC) were used to finish cotton fabric. The flame retardant properties of the finished cotton fabrics and the synergetic effects of boron and nitrogen elements were investigated and evaluated by limited oxygen index (LOI) method. The mechanism of cross-linking reaction among cotton fiber, Tri-HTAC, and boric acid was discussed by FTIR and element analysis. The thermal stability and surface morphology of the finished cotton fabrics were investigated by thermogravimetric analysis (TGA) and scanning electron microscope (SEM), respectively. The finishing system of the mixture containing boron and nitrogen showed excellent synergistic flame retardancy for cotton fabric. The cotton fabric finished with mixture system had excellent flame retardancy. The LOI value of the treated cotton fabric increased over 27.5. Tri-HTAC could form covalent bonds with cellulose fiber and boric acid. The flame retardant cotton fabric showed a slight decrease in tensile strength and whiteness. The surface morphology of flame retardant cotton fiber was smooth.

  5. Multisorbent tubes for collecting volatile organic compounds in spacecraft air

    NASA Technical Reports Server (NTRS)

    Matney, M. L.; Beck, S. W.; Limero, T. F.; James, J. T.

    2000-01-01

    The sampling capability of Tenax-TA tubes, used in the National Aeronautics and Space Administration's solid sorbent air sampler to trap and concentrate contaminants from air aboard spacecraft, was improved by incorporating two sorbents within the tubes. Existing tubes containing only Tenax-TA allowed highly volatile compounds to "break through" during collection of a 1.5 L air sample. First the carbon molecular sieve-type sorbents Carboxen 569 and Carbosieve S-III were tested for their ability to quantitatively trap the highly volatile compounds. Breakthrough volumes were determined with the direct method, whereby low ppm levels of methanol or Freon 12 in nitrogen were flowed through the sorbent tubes at 30 mL/min, and breakthrough was detected by gas chromatography. Breakthrough volumes for methanol were about 9 L/g on Carboxen 569 and 11 L/g on Carbosieve S-III; breakthrough volumes for Freon 12 were about 7 L/g on Carboxen 569 and > 26 L/g on Carbosieve S-III. Next, dual-bed tubes containing either Tenax-TA/Carbosieve S-III, Tenax-TA/Carboxen 569, or Carbotrap/Carboxen 569 to a 10-component gas mixture were exposed, in dry and in humidified air (50% relative humidity), and percentage recoveries of each compound were determined. The Tenax-TA/Carboxen 569 combination gave the best overall recoveries (75-114% for the 10 compounds). Acetaldehyde had the lowest recovery (75%) of the 10 compounds, but this value was still an improvement over either the other two sorbent combinations or the original single-sorbent tubes.

  6. Response of Dissolved Organic Matter to Warming and Nitrogen Addition

    NASA Astrophysics Data System (ADS)

    Choi, J. H.; Nguyen, H.

    2014-12-01

    Dissolved Organic Matter (DOM) is a ubiquitous mixture of soluble organic components. Since DOM is produced from the terrestrial leachate of various soil types, soil may influence the chemistry and biology of freshwater through the input of leachate and run-off. The increased temperature by climate change could dramatically change the DOM characteristics of soils through enhanced decomposition rate and losses of carbon from soil organic matter. In addition, the increase in the N-deposition affects DOM leaching from soils by changing the carbon cycling and decomposition rate of soil decay. In this study, we conducted growth chamber experiments using two types of soil (wetland and forest) under the conditions of temperature increase and N-deposition in order to investigate how warming and nitrogen addition influence the characteristics of the DOM leaching from different soil types. This leachate controls the quantity and quality of DOM in surface water systems. After 10 months of incubation, the dissolved organic carbon (DOC) concentrations decreased for almost samples in the range of 7.6 to 87.3% (ANOVA, p<0.05). The specific UV absorption (SUVA) values also decreased for almost samples after the first 3 months and then increased gradually afterward in range of 3.3 to 108.4%. Both time and the interaction between time and the temperature had the statistically significant effects on the SUVA values (MANOVA, p<0.05). Humification index (HIX) showed the significant increase trends during the duration of incubation and temperature for almost the samples (ANOVA, p<0.05). Higher decreases in the DOC values and increases in HIX were observed at higher temperatures, whereas the opposite trend was observed for samples with N-addition. The PARAFAC results showed that three fluorescence components: terrestrial humic (C1), microbial humic-like (C2), and protein-like (C3), constituted the fluorescence matrices of soil samples. During the experiment, labile DOM from the soils was

  7. Biodiversity of volatile organic compounds from five French ferns.

    PubMed

    Fons, Françoise; Froissard, Didier; Bessière, Jean-Marie; Buatois, Bruno; Rapior, Sylvie

    2010-10-01

    Five French ferns belonging to different families were investigated for volatile organic compounds (VOC) by GC-MS using organic solvent extraction. Fifty-five VOC biosynthesized from the shikimic, lipidic and terpenic pathways including monoterpenes, sesquiterpenes and carotenoid-type compounds were identified. The main volatile compound of Adiantum capillus-veneris L. (Pteridaceae) was (E)-2-decenal with a plastic or "stink bug" odor. The volatile profiles of Athyrium filix-femina (L.) Roth (Woodsiaceae) and Blechnum spicant (L.) Roth (Blechnaceae) showed similarities, with small amounts of isoprenoids and the same main volatile compounds, i.e., 2-phenylethanal (odor of lilac and hyacinth) and 1-octen-3-ol (mushroom-like odor). The main volatile compound of Dryopteris filix-mas (L.) Schott (Dryopteridaceae) was (E)-nerolidol with a woody or fresh bark note. Polyketides, as acylfilicinic acids, were mainly identified in this fern. Oreopteris limbosperma (Bellardi ex. All.) J. Holub (Thelypteridaceae), well-known for its lemon smell, contained the highest biodiversity of VOC. Eighty percent of the volatiles was issued from the terpenic pathway. The main volatiles were (E)-nerolidol, alpha-terpineol, beta-caryophyllene and other minor monoterpenes (for example, linalool, pinenes, limonene, and gamma-terpinen-7-al). It was also the fern with the highest number of carotenoid-type derivatives, which were identified in large amounts. Our results were of great interest underlying new industrial valorisation for ferns based on their broad spectrum of volatiles.

  8. New graphene fiber coating for volatile organic compounds analysis.

    PubMed

    Zhang, GuoJuan; Guo, XiaoXi; Wang, ShuLing; Wang, XueLan; Zhou, YanPing; Xu, Hui

    2014-10-15

    In the work, a novel graphene-based solid phase microextraction-gas chromatography/mass spectrometry method was developed for the analysis of trace amount of volatile organic compounds in human exhaled breath vapor. The graphene fiber coating was prepared by a one-step hydrothermal reduction reaction. The fiber with porous and wrinkled structure exhibited excellent extraction efficiency toward eight studied volatile organic compounds (two n-alkanes, five n-aldehydes and one aromatic compound). Meanwhile, remarkable thermal and mechanical stability, long lifespan and low cost were also obtained for the fiber. Under the optimal conditions, the developed method provided low limits of detection (1.0-4.5ngL(-1)), satisfactory reproducibility (3.8-13.8%) and acceptable recoveries (93-122%). The method was applied successfully to the analysis of breath samples of lung cancer patients and healthy individuals. The unique advantage of this approach includes simple setup, non-invasive analysis, cost-efficient and sufficient sensitivity. The proposed method supply us a new possibility to monitor volatile organic compounds in human exhaled breath samples.

  9. Temperature sensitivity of organic compound destruction in SCWO process.

    PubMed

    Tan, Yaqin; Shen, Zhemin; Guo, Weimin; Ouyang, Chuang; Jia, Jinping; Jiang, Weili; Zhou, Haiyun

    2014-03-01

    To study the temperature sensitivity of the destruction of organic compounds in supercritical water oxidation process (SCWO), oxidation effects of twelve chemicals in supercritical water were investigated. The SCWO reaction rates of different compounds improved to varying degrees with the increase of temperature, so the highest slope of the temperature-effect curve (imax) was defined as the maximum ratio of removal ratio to working temperature. It is an important index to stand for the temperature sensitivity effect in SCWO. It was proven that the higher imax is, the more significant the effect of temperature on the SCWO effect is. Since the high-temperature area of SCWO equipment is subject to considerable damage from fatigue, the temperature is of great significance in SCWO equipment operation. Generally, most compounds (imax > 0.25) can be completely oxidized when the reactor temperature reaches 500°C. However, some compounds (imax > 0.25) need a higher temperature for complete oxidation, up to 560°C. To analyze the correlation coefficients between imax and various molecular descriptors, a quantum chemical method was used in this study. The structures of the twelve organic compounds were optimized by the Density Functional Theory B3LYP/6-311G method, as well as their quantum properties. It was shown that six molecular descriptors were negatively correlated to imax while other three descriptors were positively correlated to imax. Among them, dipole moment had the greatest effect on the oxidation thermodynamics of the twelve organic compounds. Once a correlation between molecular descriptors and imax is established, SCWO can be run at an appropriate temperature according to molecular structure.

  10. Volatile organic compound (VOC) emissions during malting and beer manufacture

    NASA Astrophysics Data System (ADS)

    Gibson, Nigel B.; Costigan, Gavin T.; Swannell, Richard P. J.; Woodfield, Michael J.

    Estimates have been made of the amounts of volatile organic compounds (VOCs) released during different stages of beer manufacture. The estimates are based on recent measurements and plant specification data supplied by manufacturers. Data were obtained for three main manufacturing processes (malting, wort processing and fermentation) for three commercial beer types. Some data on the speciation of emitted compounds have been obtained. Based on these measurements, an estimate of the total unabated VOC emission. from the U.K. brewing industry was calculated as 3.5 kta -1, over 95% of which was generated during barley malting. This value does not include any correction for air pollution control.

  11. [Volatile Organic Compounds (VOC): definition, classification and properties].

    PubMed

    Cicolella, A

    2008-02-01

    The term volatile organic compounds includes a wide variety of chemical substances with the common feature of being carbon compounds that are volatile at ambient temperature. They can be classified into different families defined by their chemical formulae, each of which possesses common properties, although there may be major differences in terms of toxicity. For that reason the effects of VOC on health have to be considered both in an individual way and also from a global viewpoint on account of their common toxic properties and the role they play in the formation of environmental photo-oxidative pollutants, both outdoors and indoors.

  12. [Responses of rice-wheat rotation system in south Jiangsu to organic-inorganic compound fertilizers].

    PubMed

    Tian, Heng-Da; Zhang, Li; Zhang, Jian-Chao; Wang, Qiu-Jun; Xu, Da-Bing; Yibati, Halihashi; Xu, Jia-Le; Huang, Qi-Wei

    2011-11-01

    In 2006-2007, a field trial was conducted to study the effects of applying three kinds of organic-inorganic compound fertilizers [rapeseed cake compost plus inorganic fertilizers (RCC), pig manure compost plus inorganic fertilizers (PMC), and Chinese medicine residues plus inorganic fertilizers (CMC)] on the crop growth and nitrogen (N) use efficiency of rice-wheat rotation system in South Jiangsu. Grain yield of wheat and rice in the different fertilization treatments was significantly higher than the control (no fertilization). In treatments RCC, PMC and CMC, the wheat yield was 13.1%, 32.2% and 39.3% lower than that of the NPK compound fertilizer (CF, 6760 kg x hm(-2)), respectively, but the rice yield (8504-9449 kg x hm(-2)) was significantly higher than that (7919 kg x hm(-2)) of CF, with an increment of 7.4%-19.3%. In wheat season, the aboveground dry mass, N accumulation, and N use efficiency in treatments RCC, PMC, and CMC were lower than those of CF, but in rice season, these parameters were significantly higher than or as the same as CF. In sum, all the test three compound fertilizers had positive effects on the rice yield and its nitrogen use efficiency in the rice-wheat rotation system, being most significant for RCC.

  13. Group extraction of organic compounds present in liquid samples

    NASA Technical Reports Server (NTRS)

    Jahnsen, Vilhelm J. (Inventor)

    1976-01-01

    An extraction device is disclosed comprising a tube containing a substantially inert, chemically non-reactive packing material with a large surface area to volume ratio. A sample which consists of organic compounds dissolved in a liquid, is introduced into the tube. As the sample passes through the packing material it spreads over the material's large surface area to form a thin liquid film which is held on the packing material in a stationary state. A particular group or family of compounds is extractable from the sample by passing a particular solvent system consisting of a solvent and selected reagents through the packing material. The reagents cause optimum conditions to exist for the compounds of the particular family to pass through the phase boundary between the sample liquid and the solvent of the solvent system. Thus, the compounds of the particular family are separated from the sample liquid and become dissolved in the solvent of the solvent system. The particular family of compounds dissolved in the solvent, representing an extract, exits the tube together with the solvent through the tube's nozzle, while the rest of the sample remains on the packing material in a stationary state. Subsequently, a different solvent system may be passed through the packing material to extract another family of compounds from the remaining sample on the packing material.

  14. A Review of the Tissue Residue Approach for Organic and Organometallic Compounds in Aquatic Organisms

    EPA Science Inventory

    This paper reviews the tissue residue approach (TRA) for toxicity assessment as it applies to organic chemicals and some organometallic compounds (tin, mercury, and lead). Specific emphasis was placed on evaluating key factors that influence interpretation of critical body resid...

  15. Seasonal trends of dry and bulk concentration of nitrogen compounds over a rain forest in Ghana

    NASA Astrophysics Data System (ADS)

    Fattore, F.; Bertolini, T.; Materia, S.; Gualdi, S.; Thongo M'Bou, A.; Nicolini, G.; Valentini, R.; De Grandcourt, A.; Tedesco, D.; Castaldi, S.

    2014-06-01

    African tropical forests of the equatorial belt might receive significant input of extra nitrogen derived from biomass burning occurring in the north savanna belt and transported equatorward by northeastern winds. In order to test this hypothesis an experiment was set up in a tropical rain forest in the Ankasa Game Reserve and Nini-Suhien National Park (Ghana) aimed at quantifying magnitude and seasonal variability of concentrations of N compounds, present as gas and aerosol (dry nitrogen) or in the rainfall (bulk nitrogen), over the studied forest; and relating their seasonal variability to trends of local and regional winds and rainfall and to variations of fire events in the region. Three DELTA systems, implemented for monthly measurements of NO2, were mounted over a tower at 45 m height, 20 m above forest canopy to sample gas (NH3, NO2, HNO3, HCl, SO2) and aerosol (NH4+, NO3-, and several ions), together with three tanks for bulk rainfall collection (to analyze NH4+, NO3- and ion concentration). The tower was provided with a sonic anemometer to estimate local wind data. The experiment started in October 2011 and data up to October 2012 are presented. To interpret the observed seasonal trends of measured compounds, local and regional meteo data and regional satellite fire data were analyzed. The concentration of N compounds significantly increased from December to April, during the drier period, peaking from December to February when NE winds (the Harmattan) were moving dry air masses over the west-central African region, and the Intertropical Convergence Zone (ITCZ) was at its minimum latitude over the Equator. This period also coincided with fire peaks in the whole region. On the contrary, N concentration in gas, aerosol and rain decreased from May to October when prevalent winds arrived from the sea (southeast), during the monsoon period. Both ionic compositions of rain and analysis of local wind direction showed a significant and continuous presence of see

  16. Production of a High Efficiency Microbial Flocculant by Proteus mirabilis TJ-1 Using Compound Organic Wastewater

    NASA Astrophysics Data System (ADS)

    Zhang, Zhiqiang; Xia, Siqing; Zhang, Jiao

    2010-11-01

    The production of a high efficiency microbial flocculant (MBF) by Proteus mirabilis TJ-1 using compound organic wastewater was investigated. To cut down the cost of the MBF production, several nutritive organic wastewaters were selected to replace glucose and peptone as the carbon source and the nitrogen source in the optimized medium of strain TJ-1, respectively. The compound wastewater of the milk candy and the soybean milk was found to be good carbon source and nitrogen source for this strain to produce MBF. The cost-effective culture medium consists of (per liter): 800 mL wastewater of milk candy, 200 mL wastewater of soybean milk, 0.3 g MgSO4ṡ7 H2O, 5 g K2HPO4, 2 g and KH2PO4, pH 7.0. The economic cost for the MBF production can be cut down over a half by using the developed culture medium. Furthermore, the utilization of the two wastewaters in the preparation of culture medium of strain TJ-1 can not only save their big treatment cost, but also realize their resource reuse.

  17. Natural organic compounds as tracers for biomass combustion in aerosols

    SciTech Connect

    Simoneit, B.R.T. |; Abas, M.R. bin |; Cass, G.R. |; Rogge, W.F. |; Mazurek, M.A.; Standley, L.J.; Hildemann, L.M.

    1995-08-01

    Biomass combustion is an important primary source of carbonaceous particles in the global atmosphere. Although various molecular markers have already been proposed for this process, additional specific organic tracers need to be characterized. The injection of natural product organic tracers to smoke occurs primarily by direct volatilization/steam stripping and by thermal alteration based on combustion temperature. The degree of alteration increases as the burn temperature rises and the moisture content of the fuel decreases. Although the molecular composition of organic matter in smoke particles is highly variable, the molecular structures of the tracers are generally source specific. The homologous compound series and biomarkers present in smoke particles are derived directly from plant wax, gum and resin by volatilization and secondarily from pyrolysis of biopolymers, wax, gum and resin. The complexity of the organic components of smoke aerosol is illustrated with examples from controlled burns of temperate and tropical biomass fuels. Burning of biomass from temperate regions (i.e., conifers) yields characteristic tracers from diterpenoids as well as phenolics and other oxygenated species, which are recognizable in urban airsheds. The major organic components of smoke particles from tropical biomass are straight-chain, aliphatic and oxygenated compounds and triterpenoids. The precursor-to-product approach of organic geochemistry can be applied successfully to provide tracers for studying smoke plume chemistry and dispersion.

  18. Coordinated regulation of nitrogen supply mode and initial cell density for energy storage compounds production with economized nitrogen utilization in a marine microalga Isochrysis zhangjiangensis.

    PubMed

    Chi, Lei; Yao, Changhong; Cao, Xupeng; Xue, Song

    2016-01-01

    Lipids and carbohydrates are main energy storage compounds (ESC) of microalgae under stressed conditions and they are potential feedstock for biofuel production. Yet, the sustainable and commercially successful production of ESC in microalgae needs to consider nitrogen utilization efficiency. Here the impact of different initial cell densities (ICDs) on ESC accumulation in Isochrysis zhangjiangensis under two nitrogen supply modes (an initially equal concentration of nitrogen per-cell in the medium (N1) and an equal total concentration of nitrogen in the culture system (N2)) were investigated. The results demonstrated that the highest ESC yield (1.36gL(-1)) at N1, which included a maximal nitrogen supply in the cultivation system, and the highest ESC content (66.5%) and ESC productivity per mass of nitrogen (3.28gg(-1) (N) day(-1)) at N2, were all obtained under a high ICD of 8.0×10(6)cellsmL(-1). Therefore I. zhangjiangensis qualifies for ESC-enriched biomass production with economized nitrogen utilization.

  19. Vapor phase adsorption of organic compounds on octyl silicas

    NASA Astrophysics Data System (ADS)

    Roshchina, T. M.; Shoniya, N. K.; Tayakina, O. Ya.; Fadeev, A. Y.

    2011-02-01

    The influence of the modification of silica by octyltrichlorosilane with the formation of an oligomeric grafted layer (sample C8(II)) and additional silanization (sample C8(III)) on the thermodynamic adsorption characteristics (TACs) of different classes of organic compounds was investigated by gas chromatography. It was shown that the modification leads to decreased adsorption values for most of the investigated compounds (with the exception of alkanes, for which TACs on sample C8(II) approach the values observed on the initial support, due probably to additional interactions with silanol groups formed in modifying the surface with octyltrichlorosilane). It was established that blocking these silanol groups during additional silanization with trimethylsilane resulted in inert surfaces whose adsorption properties with respect to many compounds (including some capable of participating in strong specific interactions) approaches to the properties of octyl-silica with a close-packed grafted monolayer.

  20. Identification of volatile organic compounds in flowers of Astragalus lagopoides.

    PubMed

    Movafeghi, Ali; Delazar, Abbas; Amini, Majid; Asnaashari, Solmaz

    2012-01-01

    Composition of volatile organic compounds (VOCs) in flowers of Astragalus lagopoides was studied using a hydrodistillation extraction procedure coupled with gas chromatography-mass spectrometry. The analyses allowed the identification of a number of 25 compounds, among which the presence of several bioactive aromatic derivatives such as guaiacol, eugenol, linalool, α- and 4-terpineol as well as nerol was attention-grabbing. Moreover, some other compounds like cyclohexane, 2-bromoethyl with repellent function also appeared to be present in the flower. As a result, the floral VOCs profile of A. lagopoides might reflect an adaptation to attract specialised pollinator insects. These findings provide important information for advances in understanding the ecological and evolutionary perspectives of pollination biology of the giant genus Astragalus.

  1. Compositions of volatile organic compounds emitted from melted virgin and waste plastic pellets.

    PubMed

    Yamashita, Kyoko; Yamamoto, Naomichi; Mizukoshi, Atsushi; Noguchi, Miyuki; Ni, Yueyong; Yanagisawa, Yukio

    2009-03-01

    To characterize potential air pollution issues related to recycling facilities of waste plastics, volatile organic compounds (VOCs) emitted from melted virgin and waste plastics pellets were analyzed. In this study, laboratory experiments were performed to melt virgin and waste plastic pellets under various temperatures (150, 200, and 250 degrees C) and atmospheres (air and nitrogen [N2]). In the study presented here, low-density polyethylene (LDPE), polypropylene (PP), polystyrene (PS) and the recycled waste plastic pellets were used. The VOCs generated from each plastic pellets were collected by Tenax/Carboxen adsorbent tubes and analyzed by thermal desorption-gas chromatography/mass spectrometry (TD-GC/MS). The result showed the higher temperatures generated larger amounts of total VOCs (TVOCs). The VOCs emitted from the virgin plastic pellets likely originated from polymer degradation. Smaller TVOC emissions were observed in N2 atmosphere than in air atmosphere. In particular, larger amounts of the oxygenated compounds, which are generally hazardous and malodorous, were detected in air than in N2. In addition to the compounds originating from polymer degradation, the compounds originating from the plastic additives were also detected from LDPE and PS. Furthermore, various species of VOCs likely originating from contaminant inseparate polyvinyl chloride (PVC), food residues, cleaning agents, degreasers, and so on were detected from the waste plastic. Thus, melting waste plastics, as is conducted in recycling facilities, might generate larger amounts of potentially toxic compounds than producing virgin plastics.

  2. Photocatalytic destruction of volatile organic compounds in water. Master's thesis

    SciTech Connect

    Oluic, S.

    1991-12-10

    Ground water at the Anniston Army Depot in Anniston, Alabama has been found to be contaminated with volatile organic compounds. Recent research has indicated that advanced oxidation processes, namely hydrogen peroxide catalyzed by ultraviolet light radiation, can be successful in destroying these contaminants. In this process hydrogen peroxide is decomposed by ultraviolet radiation producing hydroxyl free radicals which in turn oxidize the organic compounds present. A series of batch tests and flow through experiments using this oxidation process was performed on a synthetic wastewater that closely duplicated contaminant concentration levels found at Anniston. These contaminants, 1,2 dichloroethene, trichloroethene, dichloromethane and benzene, were found readily destructed by the UV/H2O2 process both individually and in mixtures during batch testing and in flow-through experiments. All experimentation was performed utilizing a thin film reactor.

  3. Bibliography on contaminants and solubility of organic compounds in oxygen

    NASA Technical Reports Server (NTRS)

    Ordin, P. M. (Compiler)

    1975-01-01

    A compilation of a number of document citations is presented which contains information on contaminants in oxygen. Topics covered include contaminants and solubility of organic compounds in oxygen, reaction characteristics of organic compounds with oxygen, and sampling and detection limits of impurities. Each citation in the data bank contains many items of information about the document. Some of the items are title, author, abstract, corporate source, description of figures pertinent to hazards or safety, key references, and descriptors (keywords) by which the document can be retrieved. Each citation includes an evaluation of the technical contents as to being good/excellent, acceptable, or poor. The descriptors used to define the contents of the documents and subsequently used in the computerized search operations were developed for the cryogenic fluid safety by experts in the cryogenics field.

  4. Emission of volatile organic compounds (VOCs) from PVC floor coverings.

    PubMed

    Wiglusz, R; Igielska, B; Sitko, E; Nikel, G; Jarnuszkiewicz, I

    1998-01-01

    In this study 29 PVC floor coverings were tested for emission of vinyl chloride (VC) and other volatile organic compounds (VOCs). A study on the effect of higher temperature on emission of VOCs from newly manufactured PVC flooring was also carried out. The study was conducted in climatic chamber, according to Polish Standard PN-89/Z-04021. GC method was used for analyzing of the compounds emitted. VC was not emitted from any of the floorings tested. Other VOCs were emitted in different concentrations. The influence of temperature on emission was conducted at temperatures of 23 degrees C and 35 degrees C from 2 hrs up to 180 days after introduction of materials in the chamber. The increase of temperature caused increase of total volatile organic compounds (TVOC) emission during 24 hrs of experiment. Then the emission was comparable for both temperatures. After 9 days emission of identified and unidentified compounds (TVOC) showed a rapid decay and stayed on very low level during a few months. The study conducted showed that PVC floorings after 10 days of installation in the room should not be source of indoor air contamination.

  5. Destruction of organic compounds in water using supported photocatalysts

    SciTech Connect

    Zhang, Y.; Crittenden, J.C.; Hand, D.W.; Perram, D.L.

    1996-05-01

    Photocatalytic destruction of organic compounds in water is investigated using tanning lamps and fixed-bed photoreactors. Platinized titanium dioxide (Pt-TiO{sub 2}) supported on silica gel is used as a photocatalyst. Complete mineralization of influent concentrations of 4.98 mg/L tetrachloroethylene and 2.35 mg/L p-dichlorobenzene requires a reactor residence time less than 1.3 minutes. While for influent concentrations of 3.58 mg/L 2-chlorobiphenyl, 2.50 mg/L methyl ethyl ketone and 0.49 mg/L carbon tetrachloride, complete mineralization requires reactor residence times of 1.6, 10.5, and 16.8 minutes, respectively. A reactor model is developed using Langmuir-Hinshelwood kinetics and the model parameters are determined using a reference compound, trichloroethylene. Based on the results of experiments with trichloroethylene, the model predicts the mineralization of the aforementioned compounds from ultraviolet (UV) irradiance, influent concentration, hydroxyl radical rate constants, and the known physical properties of the compounds. The model is also able to predict organic destruction using solar insolation (which has a different spectral distribution from the tanning lamps) based on the UV absorption characteristics of titanium dioxide.

  6. Smart Metal-Organic Framework Coatings: Triggered Antibiofilm Compound Release.

    PubMed

    Claes, Birgit; Boudewijns, Tom; Muchez, Laurens; Hooyberghs, Geert; Van der Eycken, Erik V; Vanderleyden, Jozef; Steenackers, Hans P; De Vos, Dirk E

    2017-02-08

    Metal-organic frameworks (MOFs) have a large potential for delivery of active molecules. Here, a MOF coating is investigated as a smart host matrix for triggered release of antibiofilm compounds. In addition to a coating consisting of the regular Fe-terephthalate MIL-88B(Fe), a new hydrophobic MIL-88B(Fe) coating is synthesized in hydrothermal conditions using palmitic acid as a lattice terminating group. These porous materials are used as a host matrix for the antibiofilm compound 5-(4-chlorophenyl)-N-(2-isobutyl)-2-aminoimidazole, which has a specific biofilm-inhibiting effect at concentrations at which no activity against planktonic cells is detected. The stability of MIL-88B(Fe) in distilled water and tryptic soy broth medium is investigated, together with the ability of iron(III) chelators to serve as a trigger for controlled decomposition of MIL-88B(Fe) by metal complexation. Organic iron chelators are used to mimic the iron chelating function of siderophores, which are specific molecules excreted by biofilm-forming bacteria. Trisodium citrate is able to chelate metal ions from the junctions of the framework. By sequestration of these metal ions, the host matrix is partially degraded, resulting in an antibiofilm compound release. Finally, the antibiofilm properties against Salmonella Typhimurium are validated by monitoring biofilm growth on MOF layers either loaded or not with aminoimidazole. A strong proof-of-concept is shown for efficient inhibition of biofilm growth through triggered antibiofilm compound release.

  7. Hydroxyl radical-induced formation of highly oxidized organic compounds

    NASA Astrophysics Data System (ADS)

    Berndt, Torsten; Richters, Stefanie; Jokinen, Tuija; Hyttinen, Noora; Kurtén, Theo; Otkjær, Rasmus V.; Kjaergaard, Henrik G.; Stratmann, Frank; Herrmann, Hartmut; Sipilä, Mikko; Kulmala, Markku; Ehn, Mikael

    2016-12-01

    Explaining the formation of secondary organic aerosol is an intriguing question in atmospheric sciences because of its importance for Earth's radiation budget and the associated effects on health and ecosystems. A breakthrough was recently achieved in the understanding of secondary organic aerosol formation from ozone reactions of biogenic emissions by the rapid formation of highly oxidized multifunctional organic compounds via autoxidation. However, the important daytime hydroxyl radical reactions have been considered to be less important in this process. Here we report measurements on the reaction of hydroxyl radicals with α- and β-pinene applying improved mass spectrometric methods. Our laboratory results prove that the formation of highly oxidized products from hydroxyl radical reactions proceeds with considerably higher yields than previously reported. Field measurements support these findings. Our results allow for a better description of the diurnal behaviour of the highly oxidized product formation and subsequent secondary organic aerosol formation in the atmosphere.

  8. Hydroxyl radical-induced formation of highly oxidized organic compounds

    PubMed Central

    Berndt, Torsten; Richters, Stefanie; Jokinen, Tuija; Hyttinen, Noora; Kurtén, Theo; Otkjær, Rasmus V.; Kjaergaard, Henrik G.; Stratmann, Frank; Herrmann, Hartmut; Sipilä, Mikko; Kulmala, Markku; Ehn, Mikael

    2016-01-01

    Explaining the formation of secondary organic aerosol is an intriguing question in atmospheric sciences because of its importance for Earth's radiation budget and the associated effects on health and ecosystems. A breakthrough was recently achieved in the understanding of secondary organic aerosol formation from ozone reactions of biogenic emissions by the rapid formation of highly oxidized multifunctional organic compounds via autoxidation. However, the important daytime hydroxyl radical reactions have been considered to be less important in this process. Here we report measurements on the reaction of hydroxyl radicals with α- and β-pinene applying improved mass spectrometric methods. Our laboratory results prove that the formation of highly oxidized products from hydroxyl radical reactions proceeds with considerably higher yields than previously reported. Field measurements support these findings. Our results allow for a better description of the diurnal behaviour of the highly oxidized product formation and subsequent secondary organic aerosol formation in the atmosphere. PMID:27910849

  9. Sugar-Related Organic Compounds in Carbonaceous Meteorites

    NASA Technical Reports Server (NTRS)

    Cooper, G.; Kimmich, N.; Belisle, W.; Sarinana, J.; Brabham, K.; Garrel, L.; DeVincenzi, Donald L. (Technical Monitor)

    2001-01-01

    Sugars and related polyols are critical components of all organisms and may have been necessary for the origin of life. To date, this class of organic compounds had not been definitively identified in meteorites. This study was undertaken to determine if polyols were present in the early Solar System as constituents of carbonaceous meteorites. Results of analyses of the Murchison and Murray meteorites indicate that formaldehyde and sugar chemistry may be responsible for the presence of a variety of polyols. We conclude that polyols were present on the early Earth through delivery by asteroids and possibly comets.

  10. Oceanic Emissions and Atmospheric Depositions of Volatile Organic Compounds

    NASA Astrophysics Data System (ADS)

    Yang, M.; Blomquist, B.; Beale, R.; Nightingale, P. D.; Liss, P. S.

    2015-12-01

    Atmospheric volatile organic compounds (VOCs) affect the tropospheric oxidative capacity due to their ubiquitous abundance and relatively high reactivity towards the hydroxyal radical. Over the ocean and away from terrestrial emission sources, oxygenated volatile organic compounds (OVOCs) make up a large fraction of VOCs as airmasses age and become more oxidized. In addition to being produced or destroyed in the marine atmosphere, OVOCs can also be emitted from or deposited to the surface ocean. Here we first present direct air-sea flux measurements of three of the most abundant OVOCs - methanol, acetone, and acetaldehyde, by the eddy covariance technique from two cruises in the Atlantic: the Atlantic Meridional Transect in 2012 and the High Wind Gas Exchange Study in 2013. The OVOC mixing ratios were quantified by a high resolution proton-reaction-transfer mass spectrometer with isotopically labeled standards and their air-sea (net) fluxes were derived from the eddy covariance technique. Net methanol flux was consistently from the atmosphere to the surface ocean, while acetone varied from supersaturation (emission) in the subtropics to undersaturation (deposition) in the higher latitudes of the North Atlantic. The net air-sea flux of acetaldehyde is near zero through out the Atlantic despite the apparent supersaturation of this compound in the surface ocean. Knowing the dissolved concentrations and in situ production rates of these compounds in seawater, we then estimate their bulk atmospheric depositions and oceanic emissions. Lastly, we summarize the state of knowledge on the air-sea transport of a number of organic gasses, and postulate the magnitude and environmental impact of total organic carbon transfer between the ocean and the atmosphere.

  11. Towards understanding organic nitrogen species in emissions from post-combustion CO2 capture plants

    NASA Astrophysics Data System (ADS)

    Ge, X.; Zhang, Q.

    2012-12-01

    Post-combustion capture of carbon dioxide using aqueous amine solutions is the most advanced technology for reducing CO2 emissions from fossil fuel power plants. This technology, however, may lead to the emissions of amines and various nitrogen-containing degradation products with serious potential implications for human health and the environment. Understanding the chemistry of emissions from amine-based CO2-capture plants is therefore important and requires analytical methods that are capable of thoroughly characterizing the composition and concentration of organic nitrogen (ON) species in actual or simulated flue gas. In this study, we have developed a suite of methods for analyzing particulate and gaseous samples for the bulk and molecular compositions of these species. Specifically, we have optimized high-resolution aerosol mass spectrometry (HR-ToF-AMS) for real-time and offline analyses of the bulk chemistry of ON species. We have also developed methods for quantitatively analyzing up to 12 amino compounds using ion chromatography. In addition, by applying liquid chromatography-tandem mass spectrometry (LC-MS/MS), we have studied the molecular masses and empirical formulas of individual ON molecules. This suite of techniques has been applied for characterizing liquid and particulate samples generated from simulated amine-based CO2 capture process. The results from these analyses will be presented.

  12. Effects of airborne volatile organic compounds on plants.

    PubMed

    Cape, J N

    2003-01-01

    Routine measurements of volatile organic compounds (VOCs) in air have shown that average concentrations are very much smaller than those used in laboratory experiments designed to study the effects of VOCs on plants. However, maximum hourly concentrations of some VOCs can be 100 times larger than the average, even in rural air. Experimental studies have rarely extended for longer than a few days, so there is little information on potential long-term effects of exposure to small concentrations. This review considers the available evidence for long-term effects, based on laboratory and field data. Previous reviews of the literature from Germany and the USA are cited, prior to an assessment of the effects of individual VOCs. Although hydrocarbons from vehicle exhausts have been implicated in the observed effects on roadside vegetation, the evidence suggests that it is the nitrogen oxides in the exhaust gases that are mostly responsible. There is evidence that aromatic hydrocarbons can be metabolised in plants, although the fate of the metabolites is not known. There is a large literature on the effects of ethylene, because of its role as a plant hormone. Effects have been reported in the field, in response to industrial emissions, and dose-response experiments over several weeks in laboratory studies have clearly identified the potential for effects at ambient concentrations. The main responses are morphological (e.g. epinasty), which may be reversible, and on the development of flowers and fruit. Effects on seed production may be positive or negative, depending on the exposure concentration. Chlorinated hydrocarbons have been identified as potentially harmful to vegetation, but only one long-term experiment has studied dose-response relationships. As for ethylene, the most sensitive indication of effect was on seed production, although long-term accumulation of trichloroacetic acid in tissue may also be a problem. There is little evidence of the direct effects of

  13. Engineering biosynthesis of high-value compounds in photosynthetic organisms.

    PubMed

    O'Neill, Ellis C; Kelly, Steven

    2016-10-04

    The photosynthetic, autotrophic lifestyle of plants and algae position them as ideal platform organisms for sustainable production of biomolecules. However, their use in industrial biotechnology is limited in comparison to heterotrophic organisms, such as bacteria and yeast. This usage gap is in part due to the challenges in generating genetically modified plants and algae and in part due to the difficulty in the development of synthetic biology tools for manipulating gene expression in these systems. Plant and algal metabolism, pre-installed with multiple biosynthetic modules for precursor compounds, bypasses the requirement to install these pathways in conventional production organisms, and creates new opportunities for the industrial production of complex molecules. This review provides a broad overview of the successes, challenges and future prospects for genetic engineering in plants and algae for enhanced or de novo production of biomolecules. The toolbox of technologies and strategies that have been used to engineer metabolism are discussed, and the potential use of engineered plants for industrial manufacturing of large quantities of high-value compounds is explored. This review also discusses the routes that have been taken to modify the profiles of primary metabolites for increasing the nutritional quality of foods as well as the production of specialized metabolites, cosmetics, pharmaceuticals and industrial chemicals. As the universe of high-value biosynthetic pathways continues to expand, and the tools to engineer these pathways continue to develop, it is likely plants and algae will become increasingly valuable for the biomanufacturing of high-value compounds.

  14. Anticancer and cancer preventive compounds from edible marine organisms.

    PubMed

    Correia-da-Silva, Marta; Sousa, Emília; Pinto, Madalena M M; Kijjoa, Anake

    2017-04-06

    A direct impact of food on health, which demonstrates that dietary habit is one of the most important determinants of chronic diseases such as cancers, has led to an increased interest of the consumers toward natural bioactive compounds as functional ingredients or nutraceuticals. Epidemiological studies revealed that the populations of many Asian countries with high consumption of fish and seafood have low prevalence of particular type of cancers such as lung, breast, colorectal and prostate cancers. This observation has led to extensive investigations of the benefits of compounds present in edible marine organisms such as fish, marine invertebrates (mollusks, echinoderms) and marine algae as cancer chemopreventive agents. Interestingly, many of these marine organisms not only constitute as seafood delicacy but also as ingredients used in folk medicine of some East and Southeast Asian countries. The results of the investigations on extracts and compounds from fish (cods, anchovy, eel and also fish protein hydrolysates), mollusks (mussel, oyster, clams and abalone), as well as from sea cucumbers on the in vivo/in vitro anticancer/antitumor activities can, in part, support the health benefits of these edible marine organisms.

  15. Inorganic sulfur-nitrogen compounds: from gunpowder chemistry to the forefront of biological signaling.

    PubMed

    Cortese-Krott, Miriam M; Butler, Anthony R; Woollins, J Derek; Feelisch, Martin

    2016-04-14

    The reactions between inorganic sulfur and nitrogen-bearing compounds to form S-N containing species have a long history and, besides assuming importance in industrial synthetic processes, are of relevance to microbial metabolism; waste water treatment; aquatic, soil and atmospheric chemistry; and combustion processes. The recent discovery that hydrogen sulfide and nitric oxide exert often similar, sometimes mutually dependent effects in a variety of biological systems, and that the chemical interaction of these two species leads to formation of S-N compounds brought this chemistry to the attention of physiologists, biochemists and physicians. We here provide a perspective about the potential role of S-N compounds in biological signaling and briefly review their chemical properties and bioactivities in the context of the chronology of their discovery. Studies of the biological role of NO revealed why its chemistry is ideally suited for the tasks Nature has chosen for it; realising how the distinctive properties of sulfur can enrich this bioactivity does much to revive 'die Freude am experimentellen Spiel' of the pioneers in this field.

  16. Effect of yeast assimilable nitrogen on the synthesis of phenolic aroma compounds by Hanseniaspora vineae strains.

    PubMed

    Martin, Valentina; Boido, Eduardo; Giorello, Facundo; Mas, Albert; Dellacassa, Eduardo; Carrau, Francisco

    2016-07-01

    In several grape varieties, the dominating aryl alkyl alcohols found are the volatile group of phenylpropanoid-related compounds, such as glycosylated benzyl and 2-phenylethyl alcohol, which contribute to wine with floral and fruity aromas after being hydrolysed during fermentation. Saccharomyces cerevisiae is largely recognized as the main agent in grape must fermentation, but yeast strains belonging to other genera, including Hanseniaspora, are known to predominate during the first stages of alcoholic fermentation. Although non-Saccharomyces yeast strains have a well-recognized genetic diversity, understanding of their impact on wine flavour richness is still emerging. In this study, 11 Hansenisapora vineae strains were used to ferment a chemically defined simil-grape fermentation medium, resembling the nutrient composition of grape juice but devoid of grape-derived secondary metabolites. GC-MS analysis was performed to determine volatile compounds in the produced wines. Our results showed that benzyl alcohol, benzyl acetate and 2-phenylethyl acetate are significantly synthesized by H. vineae strains. Levels of these compounds found in fermentations with 11 H. vineae different strains were one or two orders of magnitude higher than those measured in fermentations with a known S. cerevisiae wine strain. The implications for winemaking in response to the negative correlation of benzyl alcohol, benzyl acetate and 2-phenylethyl acetate production with yeast assimilable nitrogen concentrations are discussed. Copyright © 2016 John Wiley & Sons, Ltd.

  17. Evaluations of an Enhanced Total Hydrocarbon Analyzer With Complex Mixtures of Volatile Organic Compounds

    NASA Technical Reports Server (NTRS)

    Cross, John H.; Limero, Thomas F.; James, John T.; Breach, James; Hinton, Mark

    1995-01-01

    From the earliest manned missions, the volatile organic compound (VOC) content of spacecraft air has been a concern because of a much greater potential for contamination than air in most terrestrial settings. First, the volume of air is small compared to the mass of man- made materials comprising the interior furnishings of the spacecraft. These man-made materials offgas VOCs trapped during manufacture. Second, the nitrogen fraction of the air is recycled. Any VOCs not scrubbed out with charcoal filters or aqueous condensate (mainly water expired by the crew) will accumulate in the air. Third, the crew emits metabolic VOCs. Fourth, experimental payloads can also offgas or accidentally release a VOC; in fact a major organic constituent of the atmosphere is the disinfectant isopropanol released from swabs used in medical experiments.

  18. Effects of biochar on organic nitrogen mineralization of Northeast forest soil

    NASA Astrophysics Data System (ADS)

    Du, Siyao; Tao, Jun; Luo, Xianxiang

    2016-04-01

    These years,Biochar,as a new environmental functional material,received widespread attention of scholars both in China and abroad.Biochar is applied as a soil conditioner which is because it will improve the soil texture and increase plant yields. But the influence of nitrogen cycle while biochar is added to the forest soil is still controversial. This article takes forest soil as the object of research, aiming at learning the effects of different biochar on nitrogen mineralization of forest soil,and that in the case of different incubation temperature.The results show that it can reduce the net mineralization of soil organic nitrogen. That means the addition of biochar could suppress the mineralization of forest soil organic nitrogen.In a certain range,high temperature significantly facilitate to the mineralization of soill organic nitrogen while the existence of biochar also inhibits of that.

  19. Refractory Organic Compounds in Enceladus' Ice Grains and Hydrothermal Activity

    NASA Astrophysics Data System (ADS)

    Postberg, F.; Khawaja, N.; Hsu, H. W.; Sekine, Y.; Shibuya, T.

    2015-12-01

    Cassini's Cosmic Dust Analyzer (CDA) generates time-of-flight mass spectra of individual grains impinging on the instruments target-plate. Following the analysis of salt rich ice grains emitted by Enceladus that indicated a salt-water ocean in contact with the moon's rocky core [1,2] a recent CDA analysis of nano-phase silica particles pointed at hydrothermal activity at the moon's rock/water interface [3]. The results imply temperatures above 80 - 90°C and alkaline pH values around 10 reminiscent of alkaline hydrothermal vents on Earth like the Lost City Hydrothermal Field. In this context the compositional analysis of organic components in CDA mass spectra of the ejected ice grains is of particular relevance. A multitude of volatile organic species has already been identified in the gas component of the plume [4]. As expected, we find more complex organic molecules in ice grains than in the gas indicating aromatic species, amines, and carbonyl group species. The composition of organic-bearing ice grains displays a great diversity indicating a variety of different organic species in varying concentrations. Recent spatially resolved CDA in situ measurements inside Enceladus' plume indicate that these organic compounds are especially frequent in 'young' ice grains that have just been ejected by high velocity jets. We investigate the implications of our findings with respect to ice grain formation at the water surface and inside the icy vents. We constrain the generation of organic compounds at the rock/water interface in the light of hydrothermal activity and the potential for the formation of life precursor molecules in Enceladus' ocean. Ref:[1] Postberg et al., Nature 459, 1098-1101 (2009). [2] Postberg et al., Nature 474, 620-622 (2011). [3]. Hsu, Postberg, Sekine et al., Nature, 519, 207-210 (2015). [4] Waite et al., Nature 460, 487-490 (2009).

  20. Volatile organic compound and pesticide data in public water-supply reservoirs and wells, Texas, 1999-2001

    USGS Publications Warehouse

    Mahler, Barbara J.; Gary, M.O.; Canova, M.G.; Strom, Eric W.; Fahlquist, Lynne; Dorsey, Michael E.

    2002-01-01

    To provide data for the Texas Source-Water Assessment and Protection Program, the U.S. Geological Survey conducted a synoptic survey of 48 public water-supply reservoirs and 174 public water-supply wells during 1999?2001. The surface-water samples were analyzed for volatile organic compounds and soluble pesticides. The ground-water samples were analyzed for volatile organic compounds and soluble pesticides, as well as nitrite plus nitrate nitrogen and tritium. One or more volatile organic compounds were detected in 75 percent of the reservoirs and in 9 percent of the wells. Methyl tert-butyl ether was detected most frequently in reservoirs, and toluene was detected most frequently in wells. One or more pesticides were detected in 96 percent of the reservoirs and in 33 percent of the wells. Atrazine or its breakdown product deethylatrazine was the most frequently detected pesticide. Volatile organic compounds and pesticides were not detected at concentrations exceeding the maximum contaminant level allowed in drinking water. The only constituent sampled for that exceeded its maximum contaminant level (10 milligrams per liter) was nitrate nitrogen (in 8 percent of the 174 wells).