Sample records for includes nitrogen compounds

  1. Polybenzimidazole compounds

    DOEpatents

    Klaehn, John R [Idaho Falls, ID; Peterson, Eric S [Idaho Falls, ID; Orme, Christopher J [Shelley, ID; Jones, Michael G [Chubbuck, ID; Wertsching, Alan K [Idaho Falls, ID; Luther, Thomas A [Idaho Falls, ID; Trowbridge, Tammy L [Idaho Falls, ID

    2011-11-22

    A PBI compound includes imidazole nitrogens at least a portion of which are substituted with a moiety containing a carbonyl group, the substituted imidazole nitrogens being bonded to carbon of the carbonyl group. At least 85% of the nitrogens may be substituted. The carbonyl-containing moiety may include RCO--, where R is alkoxy or haloalkyl. The PBI compound may exhibit a first temperature marking an onset of weight loss corresponding to reversion of the substituted PBI that is less than a second temperature marking an onset of decomposition of an otherwise identical PBI compound without the substituted moiety. 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 use more than 5 equivalents in relation to the imidazole nitrogens to be substituted.

  2. 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.

  3. Polybenzimidazole compounds, polymeric media, and methods of post-polymerization modifications

    DOEpatents

    Klaehn, John R.; Peterson, Eric S.; Orme, Christopher J.; Jones, Michael G.; Wertsching, Alan K.; Luther, Thomas A.; Trowbridge, Tammy L.

    2007-12-18

    A PBI compound includes imidazole nitrogens at least a portion of which are substituted with a moiety containing a carbonyl group, the substituted imidazole nitrogens being bonded to carbon of the carbonyl group. At least 85% of the nitrogens may be substituted. The carbonyl-containing moiety may include RCO--, where R is alkoxy or haloalkyl. The PBI compound may exhibit a first temperature marking an onset of weight loss corresponding to reversion of the substituted PBI that is less than a second temperature marking an onset of decomposition of an otherwise identical PBI compound without the substituted moiety. 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 use more than 5 equivalents in relation to the imidazole nitrogens to be substituted.

  4. Polymeric medium

    DOEpatents

    Klaehn, John R [Idaho Falls, ID; Peterson, Eric S [Idaho Falls, ID; Orme, Christopher J [Shelley, ID; Jones, Michael G [Chubbuck, ID; Wertsching, Alan K [Idaho Falls, ID; Luther, Thomas A [Idaho Falls, ID; Trowbridge, Tammy L [Idaho Falls, ID

    2012-03-06

    A PBI compound includes imidazole nitrogens at least a portion of which are substituted with a moiety containing a carbonyl group, the substituted imidazole nitrogens being bonded to carbon of the carbonyl group. At least 85% of the nitrogens may be substituted. The carbonyl-containing moiety may include RCO--, where R is alkoxy or haloalkyl. The PBI compound may exhibit a first temperature marking an onset of weight loss corresponding to reversion of the substituted PBI that is less than a second temperature marking an onset of decomposition of an otherwise identical PBI compound without the substituted moiety. 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 use more than 5 equivalents in relation to the imidazole nitrogens to be substituted.

  5. 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.

  6. 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.

  7. 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.

  8. 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.

  9. Theoretical studies of the nitrogen containing compounds adsorption behavior on Na(I)Y and rare earth exchanged RE(III)Y zeolites.

    PubMed

    Geng, Wei; Zhang, Haitao; Zhao, Xuefei; Zan, Wenyan; Gao, Xionghou; Yao, Xiaojun

    2015-01-01

    In this work, the adsorption behavior of nitrogen containing compounds including NH3, pyridine, quinoline, and carbazole on Na(I)Y and rare earth exchanged La(III)Y, Pr(III)Y, Nd(III)Y zeolites was investigated by density functional theory (DFT) calculations. The calculation results demonstrate that rare earth exchanged zeolites have stronger adsorption ability for nitrogen containing compounds than Na(I)Y. Rare earth exchanged zeolites exhibit strongest interaction with quinoline while weakest with carbazole. Nd(III)Y zeolites are found to have strongest adsorption to all the studied nitrogen containing compounds. The analysis of the electronic total charge density and electron orbital overlaps show that nitrogen containing compounds interact with zeolites by π-electrons of the compounds and the exchanged metal atom. Mulliken charge population analysis also proves that adsorption energies are strongly dependent on the charge transfer between the nitrogen containing molecules and exchanged metal atom in the zeolites.

  10. Electrodes including a polyphosphazene cyclomatrix, methods of forming the electrodes, and related electrochemical cells

    DOEpatents

    Gering, Kevin L; Stewart, Frederick F; Wilson, Aaron D; Stone, Mark L

    2014-10-28

    An electrode comprising a polyphosphazene cyclomatrix and particles within pores of the polyphosphazene cyclomatrix. The polyphosphazene cyclomatrix comprises a plurality of phosphazene compounds and a plurality of cross-linkages. Each phosphazene compound of the plurality of phosphazene compounds comprises a plurality of phosphorus-nitrogen units, and at least one pendant group bonded to each phosphorus atom of the plurality of phosphorus-nitrogen units. Each phosphorus-nitrogen unit is bonded to an adjacent phosphorus-nitrogen unit. Each cross-linkage of the plurality of cross-linkages bonds at least one pendant group of one phosphazene compound of the plurality of phosphazene compounds with the at least one pendant group of another phosphazene compound of the plurality of phosphazene compounds. A method of forming a negative electrode and an electrochemical cell are also described.

  11. 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.

  12. Polybenzimidazole compounds, polymeric media, and methods of post-polymerization modifications

    DOEpatents

    Klaehn, John R [Idaho Falls, ID; Peterson, Eric S [Idaho Falls, ID; Wertsching, Alan K [Idaho Falls, ID; Orme, Christopher J [Shelley, ID; Luther, Thomas A [Idaho Falls, ID; Jones, Michael G [Pocatello, ID

    2007-08-21

    A PBI compound 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 5 equivalents in relation to the imidazole nitrogens to be substituted or, preferably, about 15.

  13. 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.

  14. Detection and Quantification of Nitrogen Compounds in the First Drilled Martian Solid Samples by the Sample Analysis at Mars (SAM) Instrument Suite on the Mars Science Laboratory (MSL)

    NASA Technical Reports Server (NTRS)

    Stern, Jennifer C.; Navarro-Gonzalez, Rafael; Freissinet, Caroline; McKay, Christopher P.; Archer, P. Douglas, Jr.; Buch, Arnaud; Coll, Patrice; Eigenbrode, Jennifer L.; Franz, Heather B.; Glavin, Daniel P.; hide

    2014-01-01

    The Sampl;e 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 the three sites at Gale Crater. Preliminary detections of nitrogen species include No, HCN, ClCN, and TFMA ((trifluoro-N-methyl-acetamide), Confirmation of indigenous Martian nitrogen-bearing compounds requires quantifying N contribution from the terrestrial derivatization reagents carried for SAM's wet chemistry experiment that contribute to the SAM background. Nitrogen species detected 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.

  15. 40 CFR 442.2 - General definitions.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ..., organic chemicals including: alcohols, aldehydes, formaldehydes, phenols, peroxides, organic salts, amines, amides, other nitrogen compounds, other aromatic compounds, aliphatic organic chemicals, glycols, glycerines, and organic polymers; refractory organic compounds including: ketones, nitriles, organo-metallic...

  16. 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)

  17. Detection and Quantification of Nitrogen Compounds in the First Drilled Martian Solid Samples by the Sample Analysis at Mars (SAM) Instrument Suite on the Mars Science Laboratory (MSL)

    NASA Technical Reports Server (NTRS)

    Stern, J. C.; Navarro-Gonzales, R.; Freissinet, C.; McKay, C. P.; Archer, P. D., Jr.; Buch, A.; Brunner, A. E.; Coll, P.; Eigenbrode, J. L.; Franz, H. B.; hide

    2014-01-01

    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 at Yellowknife Bay in Gale Crater. Preliminary detections of nitrogen species include NO, HCN, ClCN, CH3CN, and TFMA (trifluoro-N-methyl-acetamide). Confirmation of indigenous Martian N-bearing compounds requires quantifying N contribution from the terrestrial derivatization reagents (e.g. N-methyl-N-tertbutyldimethylsilyltrifluoroacetamide, MTBSTFA and dimethylformamide, DMF) carried for SAM's wet chemistry experiment that contribute to the SAM background. Nitrogen species detected 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.

  18. 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/; hide

    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 unretained compounds such as NO, N2O, and NO2, which are difficult to detect by EGA-MS due to mass interferences at 30, 44 and 46, respectively. Here we present evolved gas analysis-mass spectrometry (EGA-MS) and gas chromatography mass spectrometry (GC-MS) data on the identification and quantification of these nitrogen-bearing compounds, and suggestions for their origins

  19. 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. Copyright © 2011 Elsevier Ltd. All rights reserved.

  20. Role of Nitrogen and Carbon Transport, Regulation, and Metabolism Genes for Saccharomyces cerevisiae Survival In Vivo†

    PubMed Central

    Kingsbury, Joanne M.; Goldstein, Alan L.; McCusker, John H.

    2006-01-01

    Saccharomyces cerevisiae is both an emerging opportunistic pathogen and a close relative of pathogenic Candida species. To better understand the ecology of fungal infection, we investigated the importance of pathways involved in uptake, metabolism, and biosynthesis of nitrogen and carbon compounds for survival of a clinical S. cerevisiae strain in a murine host. Potential nitrogen sources in vivo include ammonium, urea, and amino acids, while potential carbon sources include glucose, lactate, pyruvate, and fatty acids. Using mutants unable to either transport or utilize these compounds, we demonstrated that no individual nitrogen source was essential, while glucose was the most significant primary carbon source for yeast survival in vivo. Hydrolysis of the storage carbohydrate glycogen made a slight contribution for in vivo survival compared with a substantial requirement for trehalose hydrolysis. The ability to sense and respond to low glucose concentrations was also important for survival. In contrast, there was little or no requirement in vivo in this assay for any of the nitrogen-sensing pathways, nitrogen catabolite repression, the ammonium- or amino acid-sensing pathways, or general control. By using auxotrophic mutants, we found that some nitrogenous compounds (polyamines, methionine, and lysine) can be acquired from the host, while others (threonine, aromatic amino acids, isoleucine, and valine) must be synthesized by the pathogen. Our studies provide insights into the yeast-host environment interaction and identify potential antifungal drug targets. PMID:16682459

  1. 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.

  2. 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.

  3. Fermentative activity and production of volatile compounds by Saccharomyces grown in synthetic grape juice media deficient in assimilable nitrogen and/or pantothenic acid.

    PubMed

    Wang, X D; Bohlscheid, J C; Edwards, C G

    2003-01-01

    To understand the impact of assimilable nitrogen and pantothenic acid on fermentation rate and synthesis of volatile compounds by Saccharomyces under fermentative conditions. A 2 x 3 factorial experimental design was employed with the concentrations of yeast assimilable nitrogen (YAN) (60 and 250 mg l(-1)) and pantothenic acid (10, 50 and 250 microg l(-1)) as variables. In media containing 250 microg l(-1) pantothenic acid, H2S production by two different species of Saccharomyces decreased when YAN was increased from 60 to 250 mg l(-1). Conversely, H2S production was significantly higher when the concentration of assimilable nitrogen was increased if pantothenic acid was deficient (10 or 50 microg l(-1)). Yeast synthesis of other volatile compounds were impacted by both assimilable nitrogen and pantothenic acid. While growth and fermentative rate of Saccharomyces was more influenced by nitrogen than by pantothenic acid, complicated interactions exist between these nutrients that affect the synthesis of volatile compounds including H2S. This study has important implications for the winemaking industry where a better understanding of the nutritional requirements of Saccharomyces is necessary to reduce fermentation problems and to improve final product quality.

  4. Understanding nutrients in the Chesapeake Bay watershed and implications for management and restoration: the Eastern Shore

    USGS Publications Warehouse

    Ator, Scott W.; Denver, Judith M.

    2015-03-12

    The Eastern Shore includes only a small part of the Chesapeake Bay watershed, but contributes disproportionately large loads of the excess nitrogen and phosphorus that have contributed to ecological and economic degradation of the bay in recent decades. Chesapeake Bay is the largest estuary in the United States and a vital ecological and economic resource. The bay and its tributaries have been degraded in recent decades by excessive nitrogen and phosphorus in the water column, however, which cause harmful algal blooms and decreased water clarity, submerged aquatic vegetation, and dissolved oxygen. The disproportionately large nitrogen and phosphorus yields from the Eastern Shore to Chesapeake Bay are attributable to human land-use practices as well as natural hydrogeologic and soil conditions. Applications of nitrogen and phosphorus compounds to the Eastern Shore from human activities are intensive. More than 90 percent of nitrogen and phosphorus reaching the land in the Eastern Shore is applied as part of inorganic fertilizers or manure, or (for nitrogen) fixed directly from the atmosphere in cropland. Also, hydrogeologic and soil conditions promote the movement of these compounds from application areas on the landscape to groundwater and (or) surface waters, and the proximity of much of the Eastern Shore to tidal waters limits opportunities for natural removal of these compounds in the landscape. The Eastern Shore only includes 7 percent of the Chesapeake Bay watershed, but receives nearly twice as much nitrogen and phosphorus applications (per area) as the remainder of the watershed and yields greater nitrogen and phosphorus, on average, to the bay. Nitrogen and phosphorus commonly occur in streams at concentrations that may adversely affect aquatic ecosystems and have increased in recent decades.

  5. 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...

  6. A case study on the influences of long-range transport to Taiwan`s acid deposition using Taiwan air quality model

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Ken-Hui Chang; Fu-Tien Jeng

    1996-12-31

    The long-range and transboundary transport of precursors of add deposition in East Asia became important due to the industrial development around this area. We started to develop Taiwan Air Quality Model (TAQM) system since 1992, which is based on regional Acid Deposition Model (RADM) system. A typical episode in Mei-Yu season has been selected to study. A case considering all emissions within simulated domain has been run as a reference case, and another perturbed case, not including Taiwan`s emission, has been also run for analyzing quantitatively the influence of long-range transport to Taiwan`s wet deposition during the episode are 31%more » and 24% for total sulfur compounds and total nitrogen compounds respectively; but for dry deposition, only 6% is contributed by long range transport for sulfur compounds and 29% for total nitrogen compounds. Therefore, the percentages of total acid deposition contributed by long-range transport are 27% and 25% for total sulfur compounds and total nitrogen compounds, respectively.« less

  7. 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. Copyright © 2015 Elsevier Ltd. All rights reserved.

  8. 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. Copyright © 2016 Elsevier B.V. All rights reserved.

  9. Gas and aerosol fluxes. [emphasizing sulfur, nitrogen, and carbon

    NASA Technical Reports Server (NTRS)

    Martens, C. S.

    1980-01-01

    The development of remote sensing techniques to address the global need for accurate distribution and flux determinations of both man made and natural materials which affect the chemical composition of the atmosphere, the heat budget of the Earth, and the depletion, of stratospheric ozone is considered. Specifically, trace gas fluxes, sea salt aerosol production, and the effect of sea surface microlayer on gas and aerosol fluxes are examined. Volatile sulfur, carbon, nitrogen, and halocarbon compounds are discussed including a statement of the problem associated with each compound or group of compounds, a brief summary of current understanding, and suggestions for needed research.

  10. Compound-specific nitrogen isotope analysis of D-alanine, L-alanine, and valine: application of diastereomer separation to delta15N and microbial peptidoglycan studies.

    PubMed

    Takano, Yoshinori; Chikaraishi, Yoshito; Ogawa, Nanako O; Kitazato, Hiroshi; Ohkouchi, Naohiko

    2009-01-01

    We have developed an analytical method to determine the compound-specific nitrogen isotope compositions of individual amino acid enantiomers using gas chromatography/combustion/isotope ratio mass spectrometry. A novel derivatization of amino acid diastereomers by optically active (R)-(-)-2-butanol or (S)-(+)-2-butanol offers two advantages for nitrogen isotope analysis. First, chromatographic chiral separation can be achieved without the use of chiral stationary-phase columns. Second, the elution order of these compounds on the chromatogram can be switched by a designated esterification reaction. We applied the method to the compound-specific nitrogen isotope analysis of D- and L-alanine in a peptidoglycan derived from the cell walls of cultured bacteria (Firmicutes and Actinobacteria; Enterococcus faecalis, Staphylococcus aureus, Staphylococcus staphylolyticus, Lactobacillus acidophilus, Bacillus subtilis, Micrococcus luteus, and Streptomyces sp.), natural whole bacterial cells (Bacillus subtilis var. natto), (pseudo)-peptidoglycan from archaea (Methanobacterium sp.), and cell wall from eukaryota (Saccharomyces cerevisiae). We observed statistically significant differences in nitrogen isotopic compositions; e.g., delta15N ( per thousand vs air) in Staphylococcus staphylolyticus for d-alanine (19.2 +/- 0.5 per thousand, n = 4) and L-alanine (21.3 +/- 0.8 per thousand, n = 4) and in Bacillus subtilis for D-alanine (6.2 +/- 0.2 per thousand, n = 3) and L-alanine (8.2 +/- 0.4 per thousand, n = 3). These results suggest that enzymatic reaction pathways, including the alanine racemase reaction, produce a nitrogen isotopic difference in amino acid enantiomers, resulting in 15N-depleted D-alanine. This method is expected to facilitate compound-specific nitrogen isotope studies of amino acid stereoisomers.

  11. 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.

  12. [Microbial denitrogenation of fuel oil].

    PubMed

    Li, Shan-shan; Ma, Ting; Li, Guo-qiang; Liang, Feng-lai; Liu, Ru-lin

    2006-12-01

    The amount of organic nitrides contained in fuel oil is smaller than the one of organic sulfur compounds, but the existence of them is enough to affect the invariability of oil product greatly , and has a big effect on the color of oil. They also contribute to catalyst poisoning during the refining of crude oil, thus reducing the catalyzing rate of the catalyst and increasing process costs. Further more, some nitrogen organic compounds possess mutagenic and toxic activities. The combustion of these contaminants form nitrogen oxides (NOx), releasing of which to the air will cause the formation of acid rain and hence to air pollution. The classical hydroprocessing methods of nitrogen removal are costly and complicated, so the scientists are more and more interested in microbial denitrogenation. The aspects as follows are introduced, including the aromatic nitrogen compounds of fuel oil, the varieties of denitrogenation techincs, the classes of microbial denitrogenation and its biochemical pathways, molecular genetics developments of carbazole-degradative genes, and our opinion of the research direction in the future.

  13. 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.

  14. Rapid NMR method for the quantification of organic compounds in thin stillage.

    PubMed

    Ratanapariyanuch, Kornsulee; Shen, Jianheng; Jia, Yunhua; Tyler, Robert T; Shim, Youn Young; Reaney, Martin J T

    2011-10-12

    Thin stillage contains organic and inorganic compounds, some of which may be valuable fermentation coproducts. This study describes a thorough analysis of the major solutes present in thin stillage as revealed by NMR and HPLC. The concentration of charged and neutral organic compounds in thin stillage was determined by excitation sculpting NMR methods (double pulse field gradient spin echo). Compounds identified by NMR included isopropanol, ethanol, lactic acid, 1,3-propanediol, acetic acid, succinic acid, glycerophosphorylcholine, betaine, glycerol, and 2-phenylethanol. The concentrations of lactic and acetic acid determined with NMR were comparable to those determined using HPLC. HPLC and NMR were complementary, as more compounds were identified using both methods. NMR analysis revealed that stillage contained the nitrogenous organic compounds betaine and glycerophosphorylcholine, which contributed as much as 24% of the nitrogen present in the stillage. These compounds were not observed by HPLC analysis.

  15. Populational divergence in the impact of three nitrogenous compounds and their combination on larvae of the frog Pelophylax perezi (Seoane, 1885).

    PubMed

    Egea-Serrano, Andrés; Tejedo, Miguel; Torralva, Mar

    2009-08-01

    Pollution by nitrogenous compounds is a putative stressful factor that may be causally linked to the decline of amphibians. One way to understand the potentially detrimental consequences of eutrophication on amphibian populations is to investigate variation among populations differing in exposure to nitrogen, this variation potentially indicating evolutionary potential to cope with this stressor. We have examined the effect of nitrogenous compounds (NH(4)(+); NO(2)(-); NO(3)(-), both alone and in combination) on fitness-related larval traits in four populations of Pelophylax perezi naturally exposed to different degrees of eutrophication. The results indicate that both survival and larval final size decrease at higher concentrations of these compounds, either singly or in combination. Additionally, the nitrogenous compounds were more lethal and larval food consumption and final mass were significantly reduced when they were exposed to combinations of compounds. Populations inhabiting highly polluted aquatic environments tolerated higher levels of nitrogenous compounds and showed higher survival rates and larger final size than the populations of less polluted environments, suggesting the potential to adapt to increased nitrogenous contamination in this species.

  16. The Origin of Planetary Nitrogen

    NASA Technical Reports Server (NTRS)

    Owen, T.; Niemann, H.; Mahaffy, P.; Atreya, S.

    2006-01-01

    The nitrogen found today in planetary atmospheres appears to come from two sources: N2 and condensed, nitrogen-containing compounds. On Jupiter and thus presumably on the other giant planets, the nitrogen is present mainly as ammonia but was apparently delivered primarily in the form of N2, whereas on the inner planets and Titan, the nitrogen is present as N2 but was delivered as condensed compounds, dominated by ammonia. This analysis is consistent with abundance data from the Interstellar Medium and models for the solar nebula. For Jupiter and the inner planets, it is substantiated by measurements of N-l5/N-14 and is supported by investigations of comets and meteorites, soon to be supplemented by solar wind data from the Genesis Mission. The Cassini-Huygens Mission may be able to constrain models for Saturn s ammonia abundance that could test the proportion of N2 captured by the planet. The Titan story is less direct, depending on studies of noble gases. These studies in turn suggest an evolutionary stage of the early Earth s atmosphere that included the ammonia and methane postulated by S. L. Miller (1953) in his classical experiments on the production of biogenic compounds.

  17. Ionic liquids, electrolyte solutions including the ionic liquids, and energy storage devices including the ionic liquids

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Gering, Kevin L.; Harrup, Mason K.; Rollins, Harry W.

    2015-12-08

    An ionic liquid including a phosphazene compound that has a plurality of phosphorus-nitrogen units and at least one pendant group bonded to each phosphorus atom of the plurality of phosphorus-nitrogen units. One pendant group of the at least one pendant group comprises a positively charged pendant group. Additional embodiments of ionic liquids are disclosed, as are electrolyte solutions and energy storage devices including the embodiments of the ionic liquid.

  18. In Situ Bioremediation of Perchlorate and Nitrate in Vadose Zone Soil using Gaseous Electron Donor Injection Technology (GEDIT)

    DTIC Science & Technology

    2010-08-01

    maximum contaminant level mg-N/kg milligrams of nitrogen per kilogram N2 nitrogen NA not applicable ND non-detect NDMA n-nitrosodimethylamine...Pertechnetate  N-Nitrosodimethylamine ( NDMA )  Chlorinated VOCs such as trichloroethene (TCE)  Highly energetic compounds including nitro

  19. Evaluation of land use regression models (LURs) for nitrogen dioxide and benzene in four U.S. Cities.

    EPA Science Inventory

    Spatial analysis studies have included application of land use regression models (LURs) for health and air quality assessments. Recent LUR studies have collected nitrogen dioxide (NO2) and volatile organic compounds (VOCs) using passive samplers at urban air monitoring networks ...

  20. 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 under...

  1. 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 under...

  2. 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 under...

  3. 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 under...

  4. 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 under...

  5. 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/PbO 2 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 NH 4 + , 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.

  6. 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.

  7. Formation of nitrogen-containing compounds during microwave pyrolysis of microalgae: Product distribution and reaction pathways.

    PubMed

    Huang, Feng; Tahmasebi, Arash; Maliutina, Kristina; Yu, Jianglong

    2017-12-01

    The formation of nitrogen-containing compounds in bio-oil during microwave pyrolysis of Chlorella and Spirulina microalgae has been investigated in this study. Activated carbon (AC) and magnetite (Fe 3 O 4 ) were used as microwave receptors during microwave pyrolysis experiments. It has been found that the use of Fe 3 O 4 increased the total yield of bio-oil. The use of different microwave receptors did not seem to have affected the total yield of nitrogen-containing compounds in the bio-oil. However, Fe 3 O 4 promoted the formation of nitrogen-containing aliphatics, thereby reducing the formation of nitrogen-containing aromatics. The use of AC promoted the dehydration reactions during amino acid decomposition, thereby enhancing the formation of nitrogen-containing aromatics during pyrolysis. From the gas chromatography-mass spectrometry (GC-MS) analysis results, the major high-value nitrogen-containing compounds in the pyrolysis bio-oil of Chlorella and Spirulina were identified as indole and dodecamide. The formation mechanisms of nitrogen-containing compounds were proposed and discussed. Copyright © 2017 Elsevier Ltd. All rights reserved.

  8. 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. Copyright © 2015. Published by Elsevier Ltd.

  9. Evaluation of Grenache, Graciano and Tempranillo grape stilbene content after field applications of elicitors and nitrogen compounds.

    PubMed

    Portu, Javier; López, Rosa; Ewald, Philipp; Santamaría, Pilar; Winterhalter, Peter; Garde-Cerdán, Teresa

    2018-03-01

    Stilbenes have a significant biological activity and are one of the most important non-flavonoid contributors to grape and wine health-related properties. The accumulation of this class of compounds could be favored by viticultural practices such as the application of biostimulants. However, stilbene concentration also depends on several factors, including, for example, grape variety. Therefore, the aim of this work was to study the influence of foliar treatments carried out with elicitors (methyl jasmonate (MeJ) and a commercial foliar spray (YD)) and nitrogen compounds (phenylalanine and urea) on the grape stilbene composition of three varieties: Grenache, Graciano and Tempranillo. An ultra-high-pressure liquid chromatographic methodology was validated for stilbene determination. Results showed that, despite the huge influence of the grape variety, YD significantly improved stilbene composition in Grenache and Graciano, while MeJ increased the stilbene content in Graciano and Tempranillo. As for the nitrogen treatments, phenylalanine significantly increased the stilbene concentration in Graciano, while urea treatment increased it in Tempranillo. However, the application of elicitors had a greater effect than the nitrogen compounds. Overall, the foliar application of the elicitors could be a suitable practice for increasing the amount of stilbenes in grape and, therefore, its nutraceutical properties. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

  10. REACTIONS OF FUEL NITROGEN COMPOUNDS UNDER CONDITIONS OF INERT PYROLYSIS

    EPA Science Inventory

    The paper describes the pyrolysis of fossil fuels and model nitrogen compounds in helium in a small quartz plow reactor, as part of a study of the chemical mechanisms involved in the conversion of fuel-nitrogen compounds to nitric oxide (NO) during combustion. Hydrogen cyanide (H...

  11. Methods of forming boron nitride

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Trowbridge, Tammy L; Wertsching, Alan K; Pinhero, Patrick J

    A method of forming a boron nitride. The method comprises contacting a metal article with a monomeric boron-nitrogen compound and converting the monomeric boron-nitrogen compound to a boron nitride. The boron nitride is formed on the same or a different metal article. The monomeric boron-nitrogen compound is borazine, cycloborazane, trimethylcycloborazane, polyborazylene, B-vinylborazine, poly(B-vinylborazine), or combinations thereof. The monomeric boron-nitrogen compound is polymerized to form the boron nitride by exposure to a temperature greater than approximately 100.degree. C. The boron nitride is amorphous boron nitride, hexagonal boron nitride, rhombohedral boron nitride, turbostratic boron nitride, wurzite boron nitride, combinations thereof, or boronmore » nitride and carbon. A method of conditioning a ballistic weapon and a metal article coated with the monomeric boron-nitrogen compound are also disclosed.« less

  12. 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. © 2015 The Societies and Wiley Publishing Asia Pty Ltd.

  13. Biodegradation of munitions compounds by a sulfate reducing bacterial enrichment culture

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Boopathy, R.; Manning, J.

    1997-08-01

    The degradation of several munitions compounds was studied. The compounds included 2,4,6-trinitrotoluene (TNT), hexahydro-1,3,5-trinitro-1,3,5-triazine, octahydro-1,3,5,7-tetranitro-1,3,5,7-tetraazocine, 2,4,6-trinitrobenzene (TNB), and 2,4-dinitrotoluene. All of the compounds studied were degraded by the sulfate reducing bacterial (SRB) enrichment culture. The SRB culture did not use the munitions compounds as their sole source of carbon. However, all the munitions compounds tested served as the sole source of nitrogen for the SRB culture. Degradation of munitions compounds was achieved by a co-metabolic process. The SRB culture used a variety of carbon sources including pyruvate, ethanol, formate, lactate, and H{sub 2}-CO{sub 2}. The SRB culture was an incompletemore » oxidizer, unable to carry out the terminal oxidation of organic substrates to CO{sub 2} as the sole product, and it did not use acetate or methanol as a carbon source. In addition to serving as nitrogen sources, the munitions compounds also served as electron acceptors in the absence of sulfate. A soil slurry experiment with 5% and 10% munitions compounds-contaminated soil showed that the contaminant TNT was metabolized by the SRB culture in the presence of pyruvate as electron donor. This culture may be useful in decontaminating munitions compounds-contaminated soil and water under anaerobic conditions.« less

  14. Solubility Database

    National Institute of Standards and Technology Data Gateway

    SRD 106 IUPAC-NIST Solubility Database (Web, free access)   These solubilities are compiled from 18 volumes (Click here for List) of the International Union for Pure and Applied Chemistry(IUPAC)-NIST Solubility Data Series. The database includes liquid-liquid, solid-liquid, and gas-liquid systems. Typical solvents and solutes include water, seawater, heavy water, inorganic compounds, and a variety of organic compounds such as hydrocarbons, halogenated hydrocarbons, alcohols, acids, esters and nitrogen compounds. There are over 67,500 solubility measurements and over 1800 references.

  15. Deposit formation in liquid fuels. II - The effect of selected compounds on the storage stability of Jet A turbine fuel

    NASA Technical Reports Server (NTRS)

    Worstell, J. H.; Daniel, S. R.

    1981-01-01

    The influence of substituted pyridines, pyrroles, indoles, and quinolines on the storage stability of conventional Jet A turbine fuel is evaluated. Significant increases in the amount of deposit formed in accelerated storage tests are found upon addition of these compounds at levels as low as one ppm nitrogen. While the effect is correlated with basicity of the nitrogen compound within a given compound class, the correlation does not hold between classes (pyridines, quinolines, etc.). Steric hindrance at the nitrogen atom greatly inhibits deposit promotion. The characteristics, but not the elemental composition, of deposits vary with the identity of the added nitrogen compound and with deposition temperature.

  16. Metabolic Responses of Saccharomyces cerevisiae to Valine and Ammonium Pulses during Four-Stage Continuous Wine Fermentations

    PubMed Central

    Clement, T.; Perez, M.; Mouret, J. R.; Sanchez, I.; Sablayrolles, J. M.

    2013-01-01

    Nitrogen supplementation, which is widely used in winemaking to improve fermentation kinetics, also affects the products of fermentation, including volatile compounds. However, the mechanisms underlying the metabolic response of yeast to nitrogen additions remain unclear. We studied the consequences for Saccharomyces cerevisiae metabolism of valine and ammonium pulses during the stationary phase of four-stage continuous fermentation (FSCF). This culture technique provides cells at steady state similar to that of the stationary phase of batch wine fermentation. Thus, the FSCF device is an appropriate and reliable tool for individual analysis of the metabolic rerouting associated with nutrient additions, in isolation from the continuous evolution of the environment in batch processes. Nitrogen additions, irrespective of the nitrogen-containing compound added, substantially modified the formation of fermentation metabolites, including glycerol, succinate, isoamyl alcohol, propanol, and ethyl esters. This flux redistribution, fulfilling the requirements for precursors of amino acids, was consistent with increased protein synthesis resulting from increased nitrogen availability. Valine pulses, less efficient than ammonium addition in increasing the fermentation rate, were followed by a massive conversion of this amino acid in isobutanol and isobutyl acetate through the Ehrlich pathway. However, additional routes were involved in valine assimilation when added in stationary phase. Overall, we found that particular metabolic changes may be triggered according to the nature of the amino acid supplied, in addition to the common response. Both these shared and specific modifications should be considered when designing strategies to modulate the production of volatile compounds, a current challenge for winemakers. PMID:23417007

  17. Metabolic responses of Saccharomyces cerevisiae to valine and ammonium pulses during four-stage continuous wine fermentations.

    PubMed

    Clement, T; Perez, M; Mouret, J R; Sanchez, I; Sablayrolles, J M; Camarasa, C

    2013-04-01

    Nitrogen supplementation, which is widely used in winemaking to improve fermentation kinetics, also affects the products of fermentation, including volatile compounds. However, the mechanisms underlying the metabolic response of yeast to nitrogen additions remain unclear. We studied the consequences for Saccharomyces cerevisiae metabolism of valine and ammonium pulses during the stationary phase of four-stage continuous fermentation (FSCF). This culture technique provides cells at steady state similar to that of the stationary phase of batch wine fermentation. Thus, the FSCF device is an appropriate and reliable tool for individual analysis of the metabolic rerouting associated with nutrient additions, in isolation from the continuous evolution of the environment in batch processes. Nitrogen additions, irrespective of the nitrogen-containing compound added, substantially modified the formation of fermentation metabolites, including glycerol, succinate, isoamyl alcohol, propanol, and ethyl esters. This flux redistribution, fulfilling the requirements for precursors of amino acids, was consistent with increased protein synthesis resulting from increased nitrogen availability. Valine pulses, less efficient than ammonium addition in increasing the fermentation rate, were followed by a massive conversion of this amino acid in isobutanol and isobutyl acetate through the Ehrlich pathway. However, additional routes were involved in valine assimilation when added in stationary phase. Overall, we found that particular metabolic changes may be triggered according to the nature of the amino acid supplied, in addition to the common response. Both these shared and specific modifications should be considered when designing strategies to modulate the production of volatile compounds, a current challenge for winemakers.

  18. 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...

  19. Construction of an N-nitroso database for assessing dietary intake

    USDA-ARS?s Scientific Manuscript database

    Dietary N-nitroso compounds are carcinogens synthesized during food processing from two main classes of precursors, oxides of nitrogen and amines or amides. Quantification of the dietary intake of N-nitroso compounds is significant to human cancers, including those of the stomach and upper gastro-in...

  20. Evaluation of an 18-year CMAQ simulation: Seasonal variations and long-term temporal changes in sulfate and nitrate

    NASA Astrophysics Data System (ADS)

    Civerolo, Kevin; Hogrefe, Christian; Zalewsky, Eric; Hao, Winston; Sistla, Gopal; Lynn, Barry; Rosenzweig, Cynthia; Kinney, Patrick L.

    2010-10-01

    This paper compares spatial and seasonal variations and temporal trends in modeled and measured concentrations of sulfur and nitrogen compounds in wet and dry deposition over an 18-year period (1988-2005) over a portion of the northeastern United States. Substantial emissions reduction programs occurred over this time period, including Title IV of the Clean Air Act Amendments of 1990 which primarily resulted in large decreases in sulfur dioxide (SO 2) emissions by 1995, and nitrogen oxide (NO x) trading programs which resulted in large decreases in warm season NO x emissions by 2004. Additionally, NO x emissions from mobile sources declined more gradually over this period. The results presented here illustrate the use of both operational and dynamic model evaluation and suggest that the modeling system largely captures the seasonal and long-term changes in sulfur compounds. The modeling system generally captures the long-term trends in nitrogen compounds, but does not reproduce the average seasonal variation or spatial patterns in nitrate.

  1. Metal-Element Compounds of Titanium, Zirconium, and Hafnium as Pyrotechnic Fuels

    DTIC Science & Technology

    2015-05-04

    including ceramic materials in this role has been far less common. Following the development of boron carbide-based pyrotechnics in our laboratories, we...ameliorate these problems. Commercially available group 4 compounds containing hydrogen, boron , carbon, nitrogen, silicon, and phosphorus were obtained for...predicted behavior suggests that these compounds may be useful for a variety of pyrotechnic applications. 1. INTRODUCTION The recent use of boron

  2. Floatabilities of treated coal in water at room temperature

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Kwon, K.C.; Rohrer, R.L.; Lai, R.W.

    1995-04-01

    Experiments on equilibrium adsorption loadings of various probe compounds on 60-200 mesh Illinois No. 6 coal (PSOC-1539), Adaville No. 1 coal (PSOC-1544), Wyodak coal (PSOC-1545), and Pittsburgh No. 8 coal (PSOC-1549) were performed. The probe compounds include 2-methyl-1-pentanol (2M1P), 1-heptanol, benzene, and toluene. Equilibrium adsorption loadings of aromatic compounds such as toluene and benzene on the four chosen coals obey the Langmuir isotherm model up to 100 ppm in concentrations of probe compounds. Equilibrium adsorption loadings of higher aliphatic alcohols such as 2M1P and 1-heptanol on the four chosen coals do not follow both the Langmuir isotherm model and themore » Freundlich empirical adsorption model. Flotation of the coals, equilibrated with aqueous solutions of 2M1P and 1-heptanol, increases linearly with equilibrium adsorption loadings of these probe compounds on the coals. The chosen coals were treated with nitrogen and air at 1 atm and 125-225{degrees}C for 24 h. Flotation experiments of the treated coals were conducted at room temperature, using distilled water only as a flotation medium. Flotation of Adaville No. 1 coal and Wyodak coal treated with nitrogen gas is higher than that of the untreated coals and increases with treatment temperatures. Flotation of Adaville No. 1 coal treated with air at 125-225{degrees}C is not significantly different from that of untreated coal. Flotation of Pittsburgh No. 8 coal treated with air is lower than that of untreated coal and decreases with treatment temperatures. Flotation of Illinois No. 6 coal treated with nitrogen with nitrogen only is higher than that of untreated coal. Flotation of Illinois No. 6 coal treated with nitrogen at 125-175{degrees}C increases with treatment temperatures, whereas flotation of Illinois No. 6 coal treated with nitrogen at 174-225{degrees}C decreases with treatment temperatures.« less

  3. 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.

  4. 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, N 1 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.

  5. 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 with the HCN-hydrogen systematically enriched in 2H by more than 50 ‰. In the reaction of HCN with chromium, H2 and chromium-containing solid residues are formed quantitatively.

  6. DFT Insights into the Competitive Adsorption of Sulfur- and Nitrogen-Containing Compounds and Hydrocarbons on Co-Promoted Molybdenum Sulfide Catalysts

    DOE PAGES

    Rangarajan, Srinivas; Mavrikakis, Manos

    2016-04-07

    The adsorption of 20 nitrogen-/sulfur-containing and hydrocarbon compounds on the sulfur edge of cobalt-promoted molybdenum sulfide (CoMoS) catalyst was studied using density functional theory, accounting for van der Waals interactions, to elicit comparative structure–property trends across different classes of molecules relevant to hydrotreating. Unhindered organosulfur compounds preferentially adsorb on a “CUS-like” site formed by the dimerization of two neighboring sulfur atoms on the edge to create a vacancy. Nitrogen-containing compounds and 4,6-dimethyldibenzothiophene, however, prefer the brim sites. Binding energy trends indicate that nitrogen-containing compounds will inhibit hydrodesulfurization on the brim sites and, relatively weakly, on the CUS-like sites. Edge vacanciesmore » are,thus, likely to be essential for hydrodesulfurization of unhindered organosulfur compounds. Furthermore, van der Waals forces contribute significantly to the binding energy of compounds (up to 1.0 eV for large compounds such as alkyl-substituted acridines) on CoMoS.« less

  7. Food.

    ERIC Educational Resources Information Center

    Athnasios, Albert K.; And Others

    1989-01-01

    Topics covered in this review of analytical methods include: additives, adulteration, contamination, decomposition, carbohydrates, color, enzymes, fats, oils, fatty acids, flavor, identifying compounds, inorganic methods, moisture, organic acids, nitrogen processes, and vitamins. (MVL)

  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. Prebiotic Chemistry and Atmospheric Warming of Early Earth by an Active Young Sun

    NASA Technical Reports Server (NTRS)

    Airapetian, V. S.; Glocer, A.; Gronoff, G.; Hebrard, E.; Danchi, W.

    2016-01-01

    Nitrogen is a critical ingredient of complex biological molecules. Molecular nitrogen, however, which was outgassed Into the Earth's early atmosphere, is relatively chemically inert and nitrogen fixation into more chemically reactive compounds requires high temperatures. Possible mechanisms of nitrogen fixation include lightning, atmospheric shock heating by meteorites, and solar ultraviolet radiation. Here we show that nitrogen fixation in the early terrestrial atmosphere can be explained by frequent and powerful coronal mass ejection events from the young Sun -- so-called superflares. Using magnetohydrodynamic simulations constrained by Kepler Space Telescope observations, we find that successive superflare ejections produce shocks that accelerate energetic particles, which would have compressed the early Earth's magnetosphere. The resulting extended polar cap openings provide pathways for energetic particles to penetrate into the atmosphere and, according to our atmospheric chemistry simulations, initiate reactions converting molecular nitrogen, carbon dioxide and methane to the potent greenhouse gas nitrous oxide as well as hydrogen cyanide, an essential compound for life. Furthermore, the destruction of N2, C02 and CH, suggests that these greenhouse gases cannot explain the stability of liquid water on the early Earth. Instead, we propose that the efficient formation of nitrous oxide could explain a warm early Earth.

  10. Optimization of conditions for thermal treatment of rice bran using an accelerator including an organo-iron compound.

    PubMed

    Kanno, Hikari; Tachibana, Naoya; Fukushima, Masami

    2011-02-01

    A method for thermal conversion of raw organic waste (ROW) to a compost-like material (CLM) with higher levels of unsaturated carbohydrates, nitrogen- and oxygen-containing compounds was developed, in which rice bran and an organo-iron compound were employed as a model ROW and the accelerator, respectively. To evaluate the qualities of CLMs, organic substances of an acid insoluble fraction of alkaline extracts (AIAEs) from a CLM were structurally characterized by elemental analysis, pyrolysis-gas chromatography/mass spectrometry and FT-IR. The levels of unsaturated carbohydrates, and nitrogen- and oxygen-containing compounds in the CLM samples were increased by long-term treatment (60°C for 5 days, 170°C for 3 days). In particular, the high lipid content of the AIAEs, which was indicative of inadequate digestion of CLM components, was dramatically reduced in the presence of the accelerator. Copyright © 2010 Elsevier Ltd. All rights reserved.

  11. Reductive Dehalogenation of a Nitrogen Heterocyclic Herbicide in Anoxic Aquifer Slurries

    PubMed Central

    Adrian, Neal R.; Suflita, Joseph M.

    1990-01-01

    We studied the metabolic fate of bromacil in anaerobic aquifer slurries held under denitrifying, sulfate-reducing, or methanogenic conditions. Liquid chromatograhy-mass spectrometry of the slurries confirmed that bromacil was debrominated under methanogenic conditions but was not degraded under the other incubation conditions. This finding extends the range of aryl reductive dehalogenation reactions to include nitrogen heterocyclic compounds. PMID:16348103

  12. Deposit formation in liquid fuels. III - The effect of selected nitrogen compounds on diesel fuel

    NASA Technical Reports Server (NTRS)

    Worstell, J. H.; Daniel, S. R.; Frauenhoff, G.

    1981-01-01

    The influence of substituted quinolines, pyrroles, indoles, and pyridines on deposit formation in a diesel fuel is evaluated. Significant increases in deposition rate are found which are dependent upon the basicity of the nitrogen compound within a given compound class. These effects correspond closely with those produced in a Jet A fuel. Removal of highly polar fuel components renders the nitrogen compound influence inoperative. These components are therefore participants in deposit-forming reactions.

  13. 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...

  14. Fragmentation analysis of water-soluble atmospheric organic matter using ultrahigh-resolution FT-ICR mass spectrometry.

    PubMed

    Leclair, Jeffrey P; Collett, Jeffrey L; Mazzoleni, Lynn R

    2012-04-17

    Isolated water-soluble atmospheric organic matter (AOM) analytes extracted from radiation fogwater samples were analyzed using collision induced dissociation with ultrahigh-resolution Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS). Tandem mass analysis was performed on several mass ranges between 100 and 400 Da to characterize the functional groups of AOM species. Compounds containing nitrogen and/or sulfur were targeted because of the high number of oxygen atoms contained in their molecular formulas. Due to the large number of isobaric ions in the precursor isolation ranges, large numbers of product ions resulted from collision induced dissociation. Common neutral losses were assigned by matching the molecular formulas of the expected product ions with the detected product ions within the appropriate mass spectra. Since polar functional groups are expected to affect the hygroscopic properties of aerosols, the losses of H(2)O, CO(2), CH(3)OH, HNO(3), CH(3)NO(3), SO(3), SO(4) and combinations of these were specifically targeted. Among the 421 compounds studied, the most frequently observed neutral losses were CO(2) (54%), H(2)O (43%) and CH(3)OH (40%). HNO(3) losses were observed for 63% of the studied nitrogen containing compounds and 33% of the studied compounds containing both nitrogen and sulfur. SO(3) losses were observed for 85% of the studied sulfur containing compounds and 42% of studied compounds containing both nitrogen and sulfur. A number of molecular formulas matching those of monoterpene ozonolysis SOA were observed; they include organonitrates, organosulfates, and nitroxy-organosulfates. Overall, the results of fragmentation analysis of 400+ individual molecular precursors elucidate the complexity and multifunctional nature of the isolated water-soluble AOM.

  15. Electrochemical oxidation of nitrogen-heterocyclic compounds at boron-doped diamond electrode.

    PubMed

    Xing, Xuan; Zhu, Xiuping; Li, Hongna; Jiang, Yi; Ni, Jinren

    2012-01-01

    Nitrogen-heterocyclic compounds (NHCs) are toxic and bio-refractory contaminants widely spread in environment. This study investigated electrochemical degradation of NHCs at boron-doped diamond (BDD) anode with particular attention to the effect of different number and position of nitrogen atoms in molecular structure. Five classical NHCs with similar structures including indole (ID), quinoline (QL), isoquinoline (IQL), benzotriazole (BT) and benzimidazole (BM) were selected as the target compounds. Results of bulk electrolysis showed that degradation of all NHCs was fit to a pseudo first-order equation. The five compounds were degraded with the following sequence: ID>QL>IQL>BT>BM in terms of their rates of oxidation. Quantum chemical calculation was combined with experimental results to describe the degradation character of NHCs at BDD anode. A linear relationship between degradation rate and delocalization energy was observed, which demonstrated that electronic charge was redistributed through the conjugation system and accumulated at the active sites under the attack of hydroxyl radicals produced at BDD anode. Moreover, atom charge was calculated by semi empirical PM3 method and active sites of NHCs were identified respectively. Analysis of intermediates by GC-MS showed agreement with calculation results. Copyright © 2011 Elsevier Ltd. All rights reserved.

  16. Low molecular carbon compounds present in the rhizosphere control denitrification kinetics

    NASA Astrophysics Data System (ADS)

    Herold, M.; Morley, N.; Baggs, E.

    2013-12-01

    Nitrogen and carbon cycles play key roles in plant-microbe interactions in soils. Carbon is supplied by plants to microbes in the form of root exudates which includes both high and low molecular compounds. Nitrogen in turn is taken up by plants and rhizosphere microbes metabolise nitrogen compounds in several biochemical pathways. The conversion of nitrogen compounds to volatile products in the process of denitrification leads to increasing amounts of nitrous oxide (N2O) in the atmosphere. Nitrous oxide is a potent greenhouse gas and increasing emissions of N2O through intense agriculture have lead to intensified research to find possible mitigation strategies to reduce N2O production from soil. In our study we show the effect of low molecular carbon compounds, typically found in root exudates, on the dynamics of denitrification as well as the dose response effect of the single compounds. The hypothesis was tested that different compound groups change the kinetics of the different reduction steps in the biochemical pathway of denitrification, which results in lower N2O production. Experiments were performed in soil-microcosms using 15N labelling approaches to monitor denitrification products . Microcosms were maintained as slurries in order to create oxygen limiting conditions, which favours denitrification. Carbon dioxide and N2O were monitored throughout the experiments and on three destructive sampling days NO3, NO2, NO and 15N-N2 were measured. Results showed that the denitrification process was differently affected by amino acids and organic acids with higher denitrification activity observed in the presence of organic acids. The dynamics of the single reduction steps were time dependent which indicates that substrate availability plays an important role in soil microbial activity. We concluded that the activity of denitrifiers are significantly influenced by different carbon compounds, and that further studies on the effects of the composition of root exudates could contribute to N2O mitigation strategies.

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

    DOEpatents

    Huynh, My Hang V [Los Alamos, NM; Hiskey, Michael A [Los Alamos, NM

    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. Compound-specific stable isotope analysis of nitrogen-containing intact polar lipids.

    PubMed

    Svensson, Elisabeth; Schouten, Stefan; Stam, Axel; Middelburg, Jack J; Sinninghe Damsté, Jaap S

    2015-12-15

    Compound-specific isotope analysis (CSIA) of nitrogen in amino acids has proven a valuable tool in many fields (e.g. ecology). Several intact polar lipids (IPLs) also contain nitrogen, and their nitrogen isotope ratios have the potential to elucidate food-web interactions or metabolic pathways. Here we have developed novel methodology for the determination of δ(15)N values of nitrogen-containing headgroups of IPLs using gas chromatography coupled with isotope-ratio mass spectrometry. Intact polar lipids with nitrogen-containing headgroups were hydrolyzed and the resulting compounds were derivatized by (1) acetylation with pivaloyl chloride for compounds with amine and hydroxyl groups or (2) esterification using acidified 2-propanol followed by acetylation with pivaloyl chloride for compounds with both carboxyl and amine groups. The δ(15)N values of the derivatives were subsequently determined using gas chromatography/combustion/isotope-ratio mass spectrometry. Intact polar lipids with ethanolamine and amino acid headgroups, such as phosphatidylethanolamine and phosphatidylserine, were successfully released from the IPLs and derivatized. Using commercially available pure compounds it was established that δ(15)N values of ethanolamine and glycine were not statistically different from the offline-determined values. Application of the technique to microbial cultures and a microbial mat showed that the method works well for the release and derivatization of the headgroup of phosphatidylethanolamine, a common IPL in bacteria. A method to enable CSIA of nitrogen of selected IPLs has been developed. The method is suitable for measuring natural stable nitrogen isotope ratios in microbial lipids, in particular phosphatidylethanolamine, and will be especially useful for tracing the fate of nitrogen in deliberate tracer experiments. Copyright © 2015 John Wiley & Sons, Ltd.

  19. 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.

  20. Synthesis of pyrido[1,2-a]benzimidazoles and other fused imidazole derivatives with a bridgehead nitrogen atom

    NASA Astrophysics Data System (ADS)

    Begunov, Roman S.; Ryzvanovich, Galina A.

    2013-01-01

    Main methods for the synthesis of fused imidazole derivatives with a bridgehead nitrogen atom are systematically considered and summarized. The reaction mechanisms that underlie the methods for the synthesis of pyrido[1,2-a]benzimidazoles and related compounds are described. Biological properties and mechanisms of the biological activity of fused azaheterocycles are discussed. The bibliography includes 152 references.

  1. Preparation of high nitrogen compound and materials therefrom

    DOEpatents

    Huynh, My Hang V [Los Alamos, NM; Hiskey, Michael A [Los Alamos, NM

    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.

  2. Selective ionization of dissolved organic nitrogen by positive ion atmospheric pressure photoionization coupled with Fourier transform ion cyclotron resonance mass spectrometry.

    PubMed

    Podgorski, David C; McKenna, Amy M; Rodgers, Ryan P; Marshall, Alan G; Cooper, William T

    2012-06-05

    Dissolved organic nitrogen (DON) comprises a heterogeneous family of organic compounds that includes both well-known biomolecules such as urea or amino acids and more complex, less characterized compounds such as humic and fulvic acids. Typically, DON represents only a small fraction of the total dissolved organic carbon pool and therefore presents inherent problems for chemical analysis and characterization. Here, we demonstrate that DON may be selectively ionized by atmospheric pressure photionization (APPI) and characterized at the molecular level by Fourier transform ion cyclotron resonance mass spectrometry. Unlike electrospray ionization (ESI), APPI ionizes polar and nonpolar compounds, and ionization efficiency is not determined by polarity. APPI is tolerant to salts, due to the thermal treatment inherent to nebulization, and thus avoids salt-adduct formation that can complicate ESI mass spectra. Here, for dissolved organic matter from various aquatic environments, we selectively ionize DON species that are not efficiently ionized by other ionization techniques and demonstrate significant signal-to-noise increase for nitrogen species by use of APPI relative to ESI.

  3. Mass spectrometric dereplication of nitrogen-containing constituents of black cohosh (Cimicifuga racemosa L.)

    PubMed Central

    Nikolić, Dejan; Gödecke, Tanja; Chen, Shao-Nong; White, Jerry; Lankin, David C.; Pauli, Guido F.; van Breemen, Richard B.

    2011-01-01

    Black cohosh preparations are popular dietary supplements among women seeking alternative treatments for menopausal complaints. For decades, triterpene glycosides and phenolic acids have dominated the phytochemical and biomedical research on this plant. In this study, we provide evidence that black cohosh contains an unexpected and highly diverse group of secondary nitrogenous metabolites previously unknown to exist in this plant. Using a dereplication approach that combines accurate mass measurements, database searches and general knowledge of biosynthetic pathways of natural products, we identified or tentatively identified 73 nitrogen-containing metabolites, many of which are new natural products. The identified compounds belong to several structural groups including alkaloids, amides or esters of hydroxycinnamic acids and betains. Among the alkaloids, several classes such as guanidino alkaloids, isoquinolines and β-carbolines were identified. Fragmentation patterns for major compound classes are discussed, which provides a framework for the discovery of these compounds from other sources. Identification of alkaloids as a well-known group of bioactive natural products represents an important advance in better understanding of the pharmacological profile of black cohosh. PMID:22178683

  4. Water-soluble organic nitrogen in atmospheric fine particles (PM2.5) from northern California

    NASA Astrophysics Data System (ADS)

    Zhang, Qi; Anastasio, Cort; Jimenez-Cruz, Mike

    2002-06-01

    Recent studies have suggested that organic nitrogen (ON) is a ubiquitous and significant component of atmospheric dry and wet deposition, but very little is known about the concentrations and speciation of organic nitrogen in aerosol particles. In addition, while amino compounds also appear to be ubiquitous in atmospheric condensed phases, their contribution to organic nitrogen has not been previously quantified. To address these issues, we have characterized the water-soluble organic nitrogen and amino compounds in fine particles (PM2.5) collected in Davis, California, over a period of 1 year. Concentrations of water-soluble organic nitrogen (WSON) ranged from 3.1-57.8 nmol N m-3 air, peaking during winter and early spring, and typically accounted for ~20% of total nitrogen in Davis PM2.5. Assuming an average N-normalized molecular weight of 100 Da per N atom for WSON, particulate organic nitrogen had a median mass concentration of 1.6 μg m-3 air, and typically represented 18% of the total fine particle mass. The average mass of water-soluble ON in Davis PM2.5 was comparable to that of sulfate during the summer, but was significantly higher in winter. Total amino compounds (free plus combined forms) made up a significant portion of particulate organic nitrogen (median value equal to 23%), primarily due to the presence of combined amino compounds such as proteins and peptides. Total amino compounds had a median mass concentration of 290 ng m-3 air, and typically accounted for 3.3% of the total fine particle mass. These results indicate that organic nitrogen is a significant component of fine particles in northern California, and suggest that this group of compounds might play an important role in the ecological, radiative, and potential health effects of atmospheric fine particles in this region.

  5. 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 desulfurization of model diesel fuel, which contains equimolar concentrations of nitrogen (i.e., quinoline and indole), sulfur (i.e., dibenzothiophene and 4,6-dimethyldibenzothiophene), and aromatic compounds (naphthalene, 1-methylnaphthalene, and fluorene), was examined. The results revealed that when both nitrogen and sulfur compounds coexist in the fuel, the type and density of oxygen functional groups on the surface of the activated carbon are crucial for selective adsorption of nitrogen compounds but have negligible positive effects for sulfur removal. The adsorption of quinoline and indole is largely governed by specific interactions. There is enough evidence to support the importance of dipole--dipole and acid-base-specific interactions for the adsorption of both quinoline and indole. Modified carbon is a promising material for the efficient removal of the nitrogen compounds from light cycle oil (LCO). Adsorptive denitrogenation of LCO significantly improved the hydrodesulfurization (HDS) performance, especially for the removal of the refractory sulfur compounds such as 4-methyldibenzothiophene and 4,6-dimethyldibenzothiophene. An essential factor in applying activated carbon for adsorptive denitrogenation and desulfurization of liquid hydrocarbon streams is regeneration after saturation. The regeneration method of the saturated adsorbents consisted of toluene washing followed by heating to remove the remaining toluene. The results show that the spent activated carbon can be regenerated to completely recover the adsorption capacity. The high capacity and selectivity of activated carbon for nitrogen compounds, along with their ability to be regenerated, indicate that activated carbon is a promising adsorbent for the deep denitrogenation of liquid hydrocarbon streams.

  6. 78 FR 46552 - Approval and Promulgation of Air Quality Implementation Plans; Massachusetts; Regulations...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-08-01

    ... Volatile Organic Compounds and Nitrogen Oxides AGENCY: Environmental Protection Agency (EPA). ACTION... requirements for stationary sources of volatile organic compounds (VOCs) and nitrogen oxides (NO X ). This... to 310 CMR 7.19, Reasonably Available Control Technology (RACT) for Sources of Oxides of Nitrogen (NO...

  7. Comparison of element-specific capillary chromotography detectors for the identification of heteroatomic species in coal liquids

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Mitchell, S.C.; Bartle, K.D.; Holden, K.M.L.

    1994-12-31

    A series of heteroatom-rich coal and coal-derived liquids have been analysed using gas chromatography (GC) in combination with three different element-selective detectors. Selected chromatograms, including a supercritical extract (Mequinenza lignite) and aromatic fractions isolated from coal tar pitch samples are presented. In each case a series of sulphur- and/or nitrogen-containing compounds have been identified using either flame photometric detection (GC/FID/FPD) or nitrogen-phosphorous detection (GC/FID/NPD) and the information compared with that obtained from a GC coupled to an atomic emission detector (GC-AED). Preliminary results have demonstrated the relative response characteristics of each detector and their respective ability to acquire qualitative andmore » quantitative information in interfering background matrices. Further, due to the unique capabilities of GC-AED, a number of dual heteroatomic (sulphur-oxygen and nitrogen-oxygen) compounds have been identified.« less

  8. Utilization of protein-rich residues in biotechnological processes.

    PubMed

    Pleissner, Daniel; Venus, Joachim

    2016-03-01

    A drawback of biotechnological processes, where microorganisms convert biomass constituents, such as starch, cellulose, hemicelluloses, lipids, and proteins, into wanted products, is the economic feasibility. Particularly the cost of nitrogen sources in biotechnological processes can make up a large fraction of total process expenses. To further develop the bioeconomy, it is of considerable interest to substitute cost-intensive by inexpensive nitrogen sources. The aim of this mini-review was to provide a comprehensive insight of utilization methods of protein-rich residues, such as fish waste, green biomass, hairs, and food waste. The methods described include (i) production of enzymes, (ii) recovery of bioactive compounds, and/or (iii) usage as nitrogen source for microorganisms in biotechnological processes. In this aspect, the utilization of protein-rich residues, which are conventionally considered as waste, allows the development of value-adding processes for the production of bioactive compounds, biomolecules, chemicals, and materials.

  9. Prebiotic chemistry and atmospheric warming of early Earth by an active young Sun

    NASA Astrophysics Data System (ADS)

    Airapetian, V. S.; Glocer, A.; Gronoff, G.; Hébrard, E.; Danchi, W.

    2016-06-01

    Nitrogen is a critical ingredient of complex biological molecules. Molecular nitrogen, however, which was outgassed into the Earth’s early atmosphere, is relatively chemically inert and nitrogen fixation into more chemically reactive compounds requires high temperatures. Possible mechanisms of nitrogen fixation include lightning, atmospheric shock heating by meteorites, and solar ultraviolet radiation. Here we show that nitrogen fixation in the early terrestrial atmosphere can be explained by frequent and powerful coronal mass ejection events from the young Sun--so-called superflares. Using magnetohydrodynamic simulations constrained by Kepler Space Telescope observations, we find that successive superflare ejections produce shocks that accelerate energetic particles, which would have compressed the early Earth’s magnetosphere. The resulting extended polar cap openings provide pathways for energetic particles to penetrate into the atmosphere and, according to our atmospheric chemistry simulations, initiate reactions converting molecular nitrogen, carbon dioxide and methane to the potent greenhouse gas nitrous oxide as well as hydrogen cyanide, an essential compound for life. Furthermore, the destruction of N2, CO2 and CH4 suggests that these greenhouse gases cannot explain the stability of liquid water on the early Earth. Instead, we propose that the efficient formation of nitrous oxide could explain a warm early Earth.

  10. Heterogeneous photocatalytic oxidation of atmospheric trace contaminants

    NASA Technical Reports Server (NTRS)

    Ollis, David F.; Peral, Jose

    1992-01-01

    A two year study to examine the feasibility of using heterogeneous photocatalysis for spacecraft air purification was begun at North Carolina State University on November 1, 1990. The original grant proposal included examination of the rates of destruction of anticipated spacecraft-generated air contaminants, including alcohols, aldehydes, chlorinated compounds, as well as trace levels of volatile compounds containing nitrogen, sulfur, and silicon. The progress made in the second six month period of 5/1/91-11/1/91 is discussed.

  11. 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. Copyright © 2015 Elsevier Ltd. All rights reserved.

  12. Effects of the addition of different nitrogen sources in the tequila fermentation process at high sugar concentration.

    PubMed

    Arrizon, J; Gschaedler, A

    2007-04-01

    To study the effect of the addition of different nitrogen sources at high sugar concentration in the tequila fermentation process. Fermentations were performed at high sugar concentration (170 g l(-1)) using Agave tequilana Weber blue variety with and without added nitrogen from different sources (ammonium sulfate; glutamic acid; a mixture of ammonium sulfate and amino acids) during the exponential phase of growth. All the additions increased the fermentation rate and alcohol efficiency. The level of synthesis of volatile compounds depended on the source added. The concentration of amyl alcohols and isobutanol were decreased while propanol and acetaldehyde concentration increased. The most efficient nitrogen sources for fermentation rate were ammonium sulfate and the mixture of ammonium sulfate and amino acids. The level of volatile compounds produced depended upon types of nitrogen. The synthesis of some volatile compounds increased while others decreased with nitrogen addition. The addition of nitrogen could be a strategy for improving the fermentation rate and efficiency in the tequila fermentation process at high sugar Agave tequilana concentration. Furthermore, the sensory quality of the final product may change because the synthesis of the volatile compounds is modified.

  13. Seasonal changes of concentrations of inorganic and organic nitrogen in coastal marine sediments

    NASA Astrophysics Data System (ADS)

    Yamada, Hisashi; Kayama, Mitsu; Fujisawa, Kuniyasu

    1987-05-01

    The seasonal fluctuations of the concentration of nitrogenous compounds in sediments was investigated for three regions of the Seto Inland Sea in Japan; the variation of nitrogenous compounds in sediments was also studied in a laboratory experiment. The amounts of ammonium, dissolved organic nitrogen, nitrite and nitrate, as percentages of the dissolved total nitrogen of the interstitial water, were in the ranges of 47-99%, 10-50%, 0·1-0·6% and 0·3-4·1%, respectively. Ammonium was the major component and organic nitrogen was the next most important. The concentrations of these nitrogenous compounds changed seasonally: dissolved total nitrogen was higher in the warm month of September than in May; ammonium increased in warm months and decreased in cold months, but nitrite and nitrate increased in cold months. It was possible to explain the seasonal fluctuation of nitrogenous compounds in terms of the rates of the metabolic pathways of nitrogen in the sediments. Ammonium was not necessarily correlated with dissolved organic nitrogen. From this, it was considered that ammonium did not occur from solubilization of particulate organic nitrogen followed by mineralization, but from direct mineralization of particulate organic nitrogen in sediments. For the sediments of Suho Nada, Hiuchi Nada and station B-47 in Beppu Bay, the ratio of dissolved ammonium to adsorbed ammonium in the sediments was in the range 10-25%, but the ratio was 60-70% of adsorbed ammonium in the considerably anaerobic sediments at station B-45 in Beppu Bay. The ratio of dissolved ammonium to adsorbed ammonium increased with the increase of the concentration of sulfide in sediments. It was recognized that the anaerobic conditions of the sediments led to the dissolution of adsorbed ammonium.

  14. 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 vadose zone, the direct uptake of dissolved constituent from the upper portion of the saturated zone/capillary fringe, or a combination of these two processes.

  15. Identifying organic nitrogen compounds in Rocky Mountain National Park aerosols

    NASA Astrophysics Data System (ADS)

    Beem, K. B.; Desyaterik, Y.; Ozel, M. Z.; Hamilton, J. F.; Collett, J. L.

    2010-12-01

    Nitrogen deposition is an important issue in Rocky Mountain National Park (RMNP). While inorganic nitrogen contributions to the ecosystems in this area have been studied, the sources of organic nitrogen are still largely unknown. To better understand the potential sources of organic nitrogen, filter samples were collected and analyzed for organic nitrogen species. Samples were collected in RMNP using a Thermo Fisher Scientific TSP (total suspended particulate) high-volume sampler with a PM2.5 impactor plate from April - November of 2008. The samples presented the opportunity to compare two different methods for identification of individual organic nitrogen species. The first type of analysis was performed with a comprehensive two dimensional gas chromatography (GCxGC) system using a nitrogen chemiluminescence detector (NCD). The filter samples were spiked with propanil in dichloromethane to use as an internal standard and were then extracted in water followed by solid phase extraction. The GCxGC system was comprised of a volatility based separation (DB5 column) followed by a polarity based separation (RXI-17 column). A NCD was used to specifically detect nitrogen compounds and remove the complex background matrix. Individual standards were used to identify peaks by comparing retention times. This method has the added benefit of an equimolar response for nitrogen so only a single calibration is needed for all species. In the second analysis, a portion of the same filter samples were extracted in DI water and analyzed with liquid chromatography coupled with mass spectroscopy (LC/MS). The separation was performed using a C18 column and a water-methanol gradient elution. Electrospray ionization into a time of flight mass spectrometer was used for detection. High accuracy mass measurement allowed unambiguous assignments of elemental composition of resulting ions. Positive and negative polarities were used since amines tend to show up in positive mode and nitrates in negative. The differences in the number of species and what species are identified between these two methods are important for planning future analyses of organic nitrogen compounds. In addition, these data provide new insight into the potential source of organic nitrogen in RMNP. Using the GCxGC method, 39 organic nitrogen species were detected and 20 were identified. Identified species include several types of amines and phenols. The LC/MS method identified several types of cresols, amines, and nitrates.

  16. 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, Jill 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.

  17. COMBUSTION AREA SOURCES: DATA SOURCES

    EPA Science Inventory

    The report identifies, documents, and evaluates data sources for stationary area source emissions, including solid waste and agricultural burning. Area source emissions of particulate matter, sulfur dioxide, oxides of nitrogen, reactive volatile organic compounds, and carbon mon...

  18. Method of removing nitrogen monoxide from a nitrogen monoxide-containing gas using a water-soluble iron ion-dithiocarbamate, xanthate or thioxanthate

    DOEpatents

    Liu, David K.; Chang, Shih-Ger

    1989-01-01

    A method of removing nitrogen monoxide from a nitrogen monoxide-containing gas, which method comprises: (a) contacting a nitrogen oxide-containing gas with an aqueous solution of water soluble organic compound-iron ion chelate of the formula: ##STR1## wherein the water-soluble organic compound is selected from compounds of the formula: ##STR2## wherein: R is selected from hydrogen or an organic moiety having at least one polar functional group; Z is selected from oxygen, sulfur, or --N--A wherein N is nitrogen and A is hydrogen or lower alkyl having from one to four carbon atoms; and M is selected from hydrogen, sodium or potassium; and n is 1 or 2, in a contacting zone for a time and at a temperature effective to reduce the nitrogen monoxide. These mixtures are useful to provide an unexpensive method of removing NO from gases, thus reducing atmospheric pollution from flue gases.

  19. Analysis of Nonpoint-Source Ground-Water Contamination in Relation to Land Use: Assessment of Nonpoint-Source Contamination in Central Florida

    USGS Publications Warehouse

    German, Edward R.

    1996-01-01

    In central Florida, activities that might affect the quality of ground water include disposal of stormwater through drainage wells, citrus cultivation, and mining and processing of phosphate ore. Possible effects of these and other land-use activities include high concentrations of nitrogen compounds and the pesticide bromacil in the citrus area, and high concentrations of most of the major-dissolved constituents and some organic compounds in the mining area.

  20. Alkyl halide-free heteroatom alkylation and epoxidation facilitated by a recyclable polymer-supported oxidant for the in-flow preparation of diazo compounds.

    PubMed

    Nicolle, Simon M; Hayes, Christopher J; Moody, Christopher J

    2015-03-16

    Highly reactive metal carbenes, generated from simple ketones via diazo compounds, including diazo-amides and -phosphonates, using a recyclable reagent in-flow, are transient but versatile electrophiles for heteroatom alkylation reactions and for epoxide formation. The method produces no organic waste, with the only by-products being water, KI and nitrogen, without the attendant hazards of isolation of intermediate diazo compounds. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  1. Behavior and Release of Nitrogen at Mines and Quarries in Nordic Conditions

    NASA Astrophysics Data System (ADS)

    Karlsson, Teemu; Neitola, Raisa; Jermakka, Johannes; Merta, Elina; Mroueh, Ulla-Maija

    2015-04-01

    The increased extraction of mineral resources and mining activities creates added pressure on the environmental issues and a proper water management in mining areas in Finland. Among others, nitrogen compounds released from explosives or from mining processes can have a detrimental effect on the environment. Thus, this project aimed at comprehensive understanding on the nitrogen issue in the extractive industry. The project collected essential data on nitrogen compounds present in the environments of mines and quarries, and generated better understanding of the discharge and behaviour of nitrogen compounds in mining areas. The sources and balances of explosives-originated nitrogen compounds at mines and quarries of different sizes were investigated and compared. Additionally, the focus was in 'nitrogen smudging' problem of waste rocks and the intensity, as well as evolution and chemical characteristics of their nitrogen contamination. According to the results, the total load of potential nitrogen to the environment depends on the scale and type of the activity as well as the type of explosives used. The main emission sources of nitrogen are process and dewatering waters. A lysimeter study showed that the explosives originated nitrogen content of left over stones from natural stone quarrying is relatively low and ca. half of the nitrogen is leached within the first weeks after detonation. The "nitrogen smudging" of natural stone quarrying left over stones is relatively low to begin with and enhanced by the rapid flushing by rainwater, thus the residues of explosives should not be considered to prevent the utilization of otherwise mineralogically inert waste rocks of good technical quality. The overall nitrogen management should take into account the background concentrations and sensitivity of the local ecosystem. The research project "Solution for Control of Nitrogen Discharges at Mines and Quarries, (MINIMAN)" was realized during years 2012-2014 as a cooperative project with GTK, VTT and TTY together with several industrial and international partners and financed by Tekes Green Mining Programme.

  2. Comparing compound-specific and bulk stable nitrogen isotope trophic discrimination factors across multiple freshwater fish species and diets

    USDA-ARS?s Scientific Manuscript database

    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...

  3. Assessment of global nitrogen pollution in rivers using an integrated biogeochemical modeling framework.

    PubMed

    He, Bin; Kanae, Shinjiro; Oki, Taikan; Hirabayashi, Yukiko; Yamashiki, Yosuke; Takara, Kaoru

    2011-04-01

    This study has analyzed the global nitrogen loading of rivers resulting from atmospheric deposition, direct discharge, and nitrogenous compounds generated by residential, industrial, and agricultural sources. Fertilizer use, population distribution, land cover, and social census data were used in this study. A terrestrial nitrogen cycle model with a 24-h time step and 0.5° spatial resolution was developed to estimate nitrogen leaching from soil layers in farmlands, grasslands, and natural lands. The N-cycle in this model includes the major processes of nitrogen fixation, nitrification, denitrification, immobilization, mineralization, leaching, and nitrogen absorption by vegetation. The previously developed Total Runoff Integrating Pathways network was used to analyze nitrogen transport from natural and anthropogenic sources through river channels, as well as the collecting and routing of nitrogen to river mouths by runoff. Model performance was evaluated through nutrient data measured at 61 locations in several major world river basins. The dissolved inorganic nitrogen concentrations calculated by the model agreed well with the observed data and demonstrate the reliability of the proposed model. The results indicate that nitrogen loading in most global rivers is proportional to the size of the river basin. Reduced nitrate leaching was predicted for basins with low population density, such as those at high latitudes or in arid regions. Nitrate concentration becomes especially high in tropical humid river basins, densely populated basins, and basins with extensive agricultural activity. On a global scale, agriculture has a significant impact on the distribution of nitrogenous compound pollution. The map of nitrate distribution indicates that serious nitrogen pollution (nitrate concentration: 10-50 mg N/L) has occurred in areas with significant agricultural activities and small precipitation surpluses. Analysis of the model uncertainty also suggests that the nitrate export in most rivers is sensitive to the amount of nitrogen leaching from agricultural lands. Copyright © 2011 Elsevier Ltd. All rights reserved.

  4. 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.

  5. Measurement of air-surface exchange of speciated nitrogen and sulfur compounds using a modified MARGA 2S: Assessment and control of data quality

    EPA Science Inventory

    Improved measurement methods are needed to characterize dry deposition of sulfur and nitrogen compounds to assess ecosystem exposure to nutrients and acidifying compounds and to develop atmospheric deposition budgets in support of critical loads assessments. The purpose of this ...

  6. 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. Copyright © 2014, American Society for Microbiology. All Rights Reserved.

  7. Pressurized entrained-flow pyrolysis of microalgae: Enhanced production of hydrogen and nitrogen-containing compounds.

    PubMed

    Maliutina, Kristina; Tahmasebi, Arash; Yu, Jianglong

    2018-05-01

    Pressurized entrained-flow pyrolysis of Chlorella vulgaris microalgae was investigated. The impact of pressure on the yield and composition of pyrolysis products were studied. The results showed that the concentration of H 2 in bio-gas increased sharply with increasing pyrolysis pressure, while those of CO, CO 2 , CH 4 , and C 2 H 6 were dramatically decreased. The concentration of H 2 reached 88.01 vol% in bio-gas at 900 °C and 4 MPa. Higher pressures promoted the hydrogen transfer to bio-gas. The bio-oils derived from pressurized pyrolysis were rich in nitrogen-containing compounds and PAHs. The highest concentration of nitrogen-containing compounds in bio-oil was achieved at 800 °C and 1 MPa. Increasing pyrolysis pressure promoted the formation of nitrogen-containing compounds such as indole, quinoline, isoquinoline and phenanthridine. Higher pyrolysis pressures led to increased sphericity, enhanced swelling, and higher carbon order of bio-chars. Pressurized pyrolysis of biomass has a great potential for poly-generation of H 2 , nitrogen containing compounds and bio-char. Copyright © 2018 Elsevier Ltd. All rights reserved.

  8. Polymeric media comprising polybenzimidazoles N-substituted with organic-inorganic hybrid moiety

    DOEpatents

    Klaehn, John R [Idaho Falls, ID; Peterson, Eric S [Idaho Falls, ID; Wertsching, Alan K [Idaho Falls, ID; Orme, Christopher J [Shelley, ID; Luther, Thomas A [Idaho Falls, ID; Jones, Michael G [Pocatello, ID

    2009-12-15

    A PBI compound includes imidazole nitrogens at least a portion of which are substituted with an organic-inorganic hybrid moiety may be included in a separator medium. 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 separatory medium may exhibit an H.sub.2, Ar, N.sub.2, O.sub.2, CH.sub.3, or CO.sub.2 gas permeability greater than the gas permeability of a comparable separatory medium comprising the PBI compound without substitution. The separatory medium may further include an electronically conductive medium and/or ionically conductive medium. The separatory medium may be used as a membrane (semi-permeable, permeable, and non-permeable), a barrier, an ion exhcange media, a filter, a gas chromatography coating (such as stationary phase coating in affinity chromatography), etc.

  9. National Acid Precipitation Assessment Program Report to Congress: An integrated assessment

    USGS Publications Warehouse

    Burns, Douglas A.; Fenn, Mark E.; Baron, Jill S.; Lynch, Jason A.; Cosby, Bernard J.

    2011-01-01

    Acid deposition, more commonly known as acid rain, occurs when emissions of sulfur dioxide (SO2) and nitrogen oxides (NOx) react in the atmosphere with water, oxygen, and oxidants to form various acidic compounds. Prevailing winds transport the acidic compounds hundreds of miles, often across state and national borders. These acidic compounds then fall to earth in either a wet form (rain, snow, and fog) or a dry form (gases, aerosols, and particles). At certain levels, the acidic compounds, including small particles such as sulfates and nitrates, can cause many negative human health and environmental effects.

  10. Oxynitride glass production procedure

    DOEpatents

    Weidner, Jerry R.; Schuetz, Stanley T.; O'Brien, Michael H.

    1991-01-01

    The invention is a process for the preparation of high quality oxynitride glasses without resorting to high pressures. Nitrogen-containing compounds such as Si.sub.3 N.sub.4 are first encapsulated in a low melting temperature glass. Particles of the encapsulated nitrogen-containing compound are mixed with other oxide glass-formers and melted in an atmosphere of flowing nitrogen and in the presence of buffering gas to form the oxynitride glass. Glasses containing up to 15 at % nitrogen have been prepared by this method.

  11. Modification of YNbO4 and YNbTiO6 photoluminescence by nitrogen doping

    NASA Astrophysics Data System (ADS)

    Pei, H.; Su, L. M.; Cai, G. M.; Jin, Z. P.

    2018-04-01

    Niobates as multifunctional materials were of vital importance in the industry production and daily life. In present work, niobates YNbO4 and YNbTiO6 are investigated as luminescence materials. The compounds have self-activated luminescence, and it is discussed how nitrogen doping affects their electronic structure and optical properties. Various analytical techniques, including x-ray diffraction, nitrogen-content analysis, x-ray photoelectron spectroscopy, scanning electron microscopy, UV-vis absorption spectroscopy and vacuum ultraviolet emission spectroscopy at variable temperature, were used to characterize the structure, composition, crystallinity and optical performance of these niobates. By considering the luminescence mechanisms in YNbO4 and YNbTiO6, the enhanced luminescence obtained upon nitrogen doping is attributed to the presence of oxygen vacancies and nitrogen levels, which changes the band gaps of the materials. Present work demonstrates the use of nitrogen doping for improving the photoluminescence properties of self-activated niobates.

  12. Secondary targets of nitrite-derived reactive nitrogen species: nitrosation/nitration pathways, antioxidant defense mechanisms and toxicological implications.

    PubMed

    d'Ischia, Marco; Napolitano, Alessandra; Manini, Paola; Panzella, Lucia

    2011-12-19

    Nitrite, the primary metabolite of nitric oxide (NO) and a widely diffused component of human diet, plays distinct and increasingly appreciated roles in human physiology. However, when exposed to acidic environments, typically in the stomach, or under oxidative stress conditions, it may be converted to a range of reactive nitrogen species (RNS) which in turn can target a variety of biomolecules. Typical consequences of toxicological relevance include protein modification, DNA base deamination and the formation of N-nitrosamines, among the most potent mutagenic and carcinogenic compounds for humans. Besides primary biomolecules, nitrite can cause structural modifications to a variety of endogenous and exogenous organic compounds, ranging from polyunsaturated fatty acids to estrogens, tocopherol, catecholamines, furans, retinoids, dietary phenols, and a range of xenobiotics. The study of the interactions between nitrite and key food components, including phenolic antioxidants, has therefore emerged as an area of great promise for delineating innovative strategies in cancer chemoprevention. Depending on substrates and conditions, diverse reaction pathways may compete to determine product features and distribution patterns. These include nitrosation and nitration but also oxidation, via electron transfer to nitrosonium ion or nitrogen dioxide. This contribution aims to provide an overview of the main classes of compounds that can be targeted by nitrite and to discuss at chemical levels the possible reaction mechanisms under conditions that model those occurring in the stomach. The toxicological implications of the nitrite-modified molecules are finally addressed, and a rational chemical approach to the design of potent antinitrosing agents is illustrated. © 2011 American Chemical Society

  13. Regulation of Carbon Flow by Nitrogen and Light in the Red Alga, Gelidium coulteri.

    PubMed

    Macler, B A

    1986-09-01

    The red alga Gelidium coulteri Harv. photosynthetically fixed [(14)C] bicarbonate at high rates under defined conditions in unialgal laboratory culture. The fixation rate and flow of photosynthate into various end products were dependent on the nitrogen status of the tissue. Plants fed luxury levels of nitrogen (approximately 340 micromolar) showed fixation rates several-fold higher than those seen for plants starved for nitrogen. The addition of NO(3) (-) or NH(4) (+) to such starved plants further inhibited fixation over at least the first several hours after addition. The majority of (14)C after incubations of 30 minutes to 8 hours was found in the compounds floridoside, agar and floridean starch. In addition, amino acids and intermediate compounds of the reductive pentose phosphate pathway, glycolytic pathway and tricarboxylic acid cycle were detected. Nitrogen affected the partitioning of labeled carbon into these compounds. Plants under luxury nitrogen conditions had higher floridoside levels and markedly lower amounts of agar and starch than found in plants limited for nitrogen. Amino acid, phycobiliprotein and chlorophyll levels were also significantly higher in nitrogen-enriched plants. Addition of NO(3) (-) to starved plants led to an increase in floridoside, tricarboxylic acid cycle intermediates and amino acids within 1 hour and inhibited carbon flow into agar and starch. Carbon fixation in the dark was only 1 to 7% of that seen in the light. Dark fixation of [(14)C]bicarbonate yielded label primarily in tricarboxylic acid cycle intermediates, amino acids and polysaccharides. Nitrogen stimulated amino acid synthesis at the expense of agar and starch. Floridoside was only a minor component in the dark. Pulse-chase experiments, designed to show carbon turnover, indicated a 2-fold increase in labeling of agar over 96 hours of chase in the light. No increases were seen in the dark. Low molecular weight pools, including floridoside, decreased 2- to 5-fold over this period under both light and dark conditions. Nitrogen status did not influence turnover. There was little or no organic carbon released into the culture medium over this period. The results are consistent with biosynthetic pathways to floridoside and agar that share the common intermediate UDP-d-galactose. It is hypothesized that synthesis of floridoside is regulated by nitrogen and light at the enzymic level.

  14. Regulation of Carbon Flow by Nitrogen and Light in the Red Alga, Gelidium coulteri1

    PubMed Central

    Macler, Bruce A.

    1986-01-01

    The red alga Gelidium coulteri Harv. photosynthetically fixed [14C] bicarbonate at high rates under defined conditions in unialgal laboratory culture. The fixation rate and flow of photosynthate into various end products were dependent on the nitrogen status of the tissue. Plants fed luxury levels of nitrogen (approximately 340 micromolar) showed fixation rates several-fold higher than those seen for plants starved for nitrogen. The addition of NO3− or NH4+ to such starved plants further inhibited fixation over at least the first several hours after addition. The majority of 14C after incubations of 30 minutes to 8 hours was found in the compounds floridoside, agar and floridean starch. In addition, amino acids and intermediate compounds of the reductive pentose phosphate pathway, glycolytic pathway and tricarboxylic acid cycle were detected. Nitrogen affected the partitioning of labeled carbon into these compounds. Plants under luxury nitrogen conditions had higher floridoside levels and markedly lower amounts of agar and starch than found in plants limited for nitrogen. Amino acid, phycobiliprotein and chlorophyll levels were also significantly higher in nitrogen-enriched plants. Addition of NO3− to starved plants led to an increase in floridoside, tricarboxylic acid cycle intermediates and amino acids within 1 hour and inhibited carbon flow into agar and starch. Carbon fixation in the dark was only 1 to 7% of that seen in the light. Dark fixation of [14C]bicarbonate yielded label primarily in tricarboxylic acid cycle intermediates, amino acids and polysaccharides. Nitrogen stimulated amino acid synthesis at the expense of agar and starch. Floridoside was only a minor component in the dark. Pulse-chase experiments, designed to show carbon turnover, indicated a 2-fold increase in labeling of agar over 96 hours of chase in the light. No increases were seen in the dark. Low molecular weight pools, including floridoside, decreased 2- to 5-fold over this period under both light and dark conditions. Nitrogen status did not influence turnover. There was little or no organic carbon released into the culture medium over this period. The results are consistent with biosynthetic pathways to floridoside and agar that share the common intermediate UDP-d-galactose. It is hypothesized that synthesis of floridoside is regulated by nitrogen and light at the enzymic level. PMID:16664980

  15. 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.

  16. Measurement of air-surface exchange of speciated nitrogen and sulfur compounds using a modified MARGA 2S: ? Concentrations and fluxes above a grass field

    EPA Science Inventory

    Improved measurement methods are needed to characterize dry deposition of sulfur and nitrogen compounds to assess ecosystem exposure to nutrients and acidifying compounds and to develop atmospheric deposition budgets in support of critical loads assessments. The purpose of this s...

  17. Nitrogen-based drugs are not essential for blockade of monoamine transporters.

    PubMed

    Madras, B K; Pristupa, Z B; Niznik, H B; Liang, A Y; Blundell, P; Gonzalez, M D; Meltzer, P C

    1996-12-01

    In brain, monoamine transporters are principal targets of widely used therapeutic drugs including antidepressants, methylphenidate (Ritalin), and the addictive drug cocaine. Without exception, these transport blocking agents contain an amine nitrogen. A prevalent view and untested premise is that an amine nitrogen is needed to bind to the same counterion on the transporter as does the amine nitrogen of the monoamine neurotransmitter. We report that several compounds without nitrogen (8-oxa-bicyclo-3-aryl-[3.2.1] octanes, or aryloxatropanes) are active at monoamine transporters. One of these, tropoxane (0-914), bound with high affinity to the dopamine (IC50: 3.35 +/- 0.39 nM), serotonin (IC50: 6.52 +/- 2.05 nM), and norepinephrine (IC50: 20.0 +/- 0.3 nM) transporters in monkey brain, the human striatal dopamine transporter (IC50: 5.01 +/- 1.74 nM), and blocked dopamine transport (IC50: 7.2 +/- 3.0 nM) in COS-7 cells transfected with the human dopamine transporter. These unique compounds require a revision of current concepts of the drug binding domains on monoamine transporters, open avenues for discovery of a new generation of drugs and raise the issue of whether mammalian transporters and receptors may respond to, as yet, undiscovered non-amine bearing neurotransmitters or drugs.

  18. Identification of combustion intermediates in low-pressure premixed pyridine/oxygen/argon flames.

    PubMed

    Tian, Zhenyu; Li, Yuyang; Zhang, Taichang; Zhu, Aiguo; Qi, Fei

    2008-12-25

    Combustion intermediates of two low-pressure premixed pyridine/oxygen flames with respective equivalence ratios of 0.56 (C/O/N = 1:4.83:0.20) and 2.10 (C/O/N = 1:1.29:0.20) have been identified with tunable synchrotron vacuum ultraviolet (VUV) photoionization and molecular-beam mass spectrometry techniques. About 80 intermediates in the rich flame and 60 intermediates in the lean flame, including nitrogenous, oxygenated, and hydrocarbon intermediates, have been identified by measurements of photoionization mass spectra and photoionization efficiency spectra. Some radicals and new nitrogenous intermediates are identified in the present work. The experimental results are useful for studying the conversion of volatile nitrogen compounds and understanding the formation mechanism of NO(x) in flames of nitrogenous fuels.

  19. Tertiary nitrogen heterocyclic material to reduce moisture-induced damage in asphalt-aggregate mixtures

    DOEpatents

    Plancher, Henry; Petersen, Joseph C.

    1982-01-01

    Asphalt-aggregate roads crack when subjected to freezing and thawing cycles. Herein, the useful life of asphalts are substantially improved by a minor amount of a moisture damage inhibiting agent selected from compounds having a pyridine moiety, including acid salts of such compounds. A shale oil fraction may serve as the source of the improving agent and may simply be blended with conventional petroleum asphalts.

  20. USSR and Eastern Europe Scientific Abstracts, Physics and Mathematics, Number 36

    DTIC Science & Technology

    1977-07-06

    Russian, 2 Western. Calorimetry USSR COMBUSTION OF EXPLOSIVE COMPOUNDS WITH NITROGEN-NITROGEN BONDS Novosibirsk FIZIKA GORENIYA I VZRYVA in...trinitrosoamine was studied. The function U(IQ) was determined for some of these compounds (-80 - + 150°C) and the thermocouples embedded in the compounds at...method of calculation is apparently applicable to analysis of nitro esters and nitro compounds with the C-NO2 bond in the region of kinetically

  1. Global nitrogen overload problem grows critical

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Moffat, A.S.

    1998-02-13

    This article discusses a global problem due to man`s intervention in the biosphere resulting from an increased production and usage of products producing nitrogen compounds which can be fixed in ecosystems. This problem was recognized on small scales even in the 1960`s, but recent studies on a more global scale show that the amount of nitrogen compounds in river runoff is strongly related to the use of synthetic fertilizers, fossil-fuel power plants, and automobile emissions. The increased fixed nitrogen load is exceeding the ability of some ecosystems to use or break the compounds down, resulting in a change in themore » types of flora and fauna which are found to inhabit the ecosystems, and leading to decreased biodiversity.« less

  2. Method for combined removal of mercury and nitrogen oxides from off-gas streams

    DOEpatents

    Mendelsohn, Marshall H [Downers Grove, IL; Livengood, C David [Lockport, IL

    2006-10-10

    A method for removing elemental Hg and nitric oxide simultaneously from a gas stream is provided whereby the gas stream is reacted with gaseous chlorinated compound to convert the elemental mercury to soluble mercury compounds and the nitric oxide to nitrogen dioxide. The method works to remove either mercury or nitrogen oxide in the absence or presence of each other.

  3. 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.

  4. Nitrogen containing organic compounds in aerosols: results from TD-PTR-MS measurements during the CALNEX campaign

    NASA Astrophysics Data System (ADS)

    Holzinger, R.; Timkovsky, J.

    2011-12-01

    During the CALNEX campaign we deployed a thermal-desorption proton-transfer-reaction mass-spectrometer (TD-PTR-MS) at the Caltech ground site near downtown Los Angeles. The instrument was equipped with a time of flight mass spectrometer and a mass resolution power of ~4000 was realized under field conditions. Mass peaks could be determined at accuracy levels of +/- 3 mDa, which allowed identification by the empirical formula rather than by m/z alone. Over 900 ion species have been detected in aerosols. The largest signals (m/z 18.032, NH4+, and 45.991, NO2+) were attributed to ammonia and nitrate, respectively. 350 ion species accounted for 80% of the total measured mass of organic aerosol species. Of these, 66 species contained one nitrogen atom and 73 species contained two nitrogen atoms. Each group accounted for ~15% of the total measured mass. This suggests a ~30% contribution of nitrogen compounds to the total organic aerosol burden. However, this number could still underestimate the real fraction of nitrogen compounds for two reasons: (1) thermal desorption may cause decomposition of nitrogen compounds. E.g. peroxy nitrates rapidly decompose at temperatures above 100°C and produce NO2 which cannot be detected by the PTR-MS. (2) During protonation nitrogen functional groups may be preferentially lost. E.g. alkyl nitrates typically fragment during protonation in the PTR-MS. A minor fraction of the alkyl nitrates is detected as NO2+ and contributes to the signal at m/z 45.991, however, the majority is detected as alkyl ion without nitrogen. At this point it the overall loss of nitrogen due to these processes is hard to quantify. Our findings suggest that nitrogen chemistry plays a crucial role in producing secondary organic aerosol.

  5. Nitrogen emission and deposition budget in West and Central Africa

    NASA Astrophysics Data System (ADS)

    Galy-Lacaux, C.; Delon, C.

    2014-12-01

    Atmospheric nitrogen depends on land surface exchanges of nitrogen compounds. In Sub Saharan Africa, deposition and emission fluxes of nitrogen compounds are poorly quantified, and are likely to increase in the near future due to land use change and anthropogenic pressure. This work proposes an estimate of atmospheric N compounds budget in West and Central Africa, along an ecosystem transect, from dry savanna to wet savanna and forest, for years 2000-2007. The budget may be considered as a one point in time budget, to be included in long term studies as one of the first reference point for Sub Saharan Africa. Gaseous dry deposition fluxes are estimated by considering N compounds concentrations measured in the frame of the IDAF network (IGAC/DEBITS/AFrica) at the monthly scale and modeling of deposition velocities at the IDAF sites, taking into account the bi directional exchange of ammonia. Particulate dry deposition fluxes are calculated using the same inferential method. Wet deposition fluxes are calculated from measurements of ammonium and nitrate chemical content in precipitations at the IDAF sites combined with the annual rainfall amount. In terms of emission, biogenic NO emissions are simulated at each IDAF site with a surface model coupled to an emission module elaborated from an artificial neural network equation. Ammonia emissions from volatilization are calculated from literature data on livestock quantity in each country and N content in manure. NOx and NH3 emission from biomass burning and domestic fires are estimated from satellite data and emission factors. The total budget shows that emission sources of nitrogen compounds are in equilibrium with deposition fluxes in dry and wet savannas, with respectively 7.40 (±1.90) deposited and 9.01 (±3.44) kgN ha-1 yr-1 emitted in dry savanna, 8.38 (±2.04) kgN ha-1 yr-1 deposited and 9.60 (±0.69) kgN ha-1 yr-1 emitted in wet savanna. In forested ecosystems, the total budget is dominated by wet plus dry deposition processes (14.75 ± 2.36 kgN ha-1 yr-1), compared to emissions processes (8.54 ± 0.50 kgN ha-1 yr-1).

  6. Compounds from the Fruits of the Popular European Medicinal Plant Vitex agnus-castus in Chemoprevention via NADP(H):Quinone Oxidoreductase Type 1 Induction.

    PubMed

    Li, Shenghong; Qiu, Shengxiang; Yao, Ping; Sun, Handong; Fong, Harry H S; Zhang, Hongjie

    2013-01-01

    As part of our continuing efforts in the search for potential biologically active compounds from medicinal plants, we have isolated 18 compounds including two novel nitrogen containing diterpenes from extracts of the fruits of Vitex agnus-castus. These isolates, along with our previously obtained novel compound vitexlactam A (1), were evaluated for potential biological effects, including cancer chemoprevention. Chemically, the nitrogenous isolates were found to be two labdane diterpene alkaloids, each containing an α , β -unsaturated γ -lactam moiety. Structurally, they were elucidated to be 9 α -hydroxy-13(14)-labden-16,15-amide (2) and 6 β -acetoxy-9 α -hydroxy-13(14)-labden-15,16-amide (3), which were named vitexlactams B and C, respectively. The 15 known isolates were identified as vitexilactone (4), rotundifuran (5), 8-epi-manoyl oxide (6), vitetrifolin D (7), spathulenol (8), cis-dihydro-dehydro-diconiferylalcohol-9-O- β -D-glucoside (9), luteolin-7-O-glucoside (10), 5-hydroxy-3,6,7,4'-tetramethoxyflavone (11), casticin (12), artemetin (13), aucubin (14), agnuside (15), β -sitosterol (16), p-hydroxybenzoic acid (17), and p-hydroxybenzoic acid glucose ester (18). All compound structures were determined/identified on the basis of 1D and/or 2D NMR and mass spectrometry techniques. Compounds 6, 8, 9, and 18 were reported from a Vitex spieces for the first time. The cancer chemopreventive potentials of these isolates were evaluated for NADP(H):quinone oxidoreductase type 1 (QR1) induction activity. Compound 7 demonstrated promising QR1 induction effect, while the new compound vitexlactam (3) was only slightly active.

  7. Compounds from the Fruits of the Popular European Medicinal Plant Vitex agnus-castus in Chemoprevention via NADP(H):Quinone Oxidoreductase Type 1 Induction

    PubMed Central

    Li, Shenghong; Qiu, Shengxiang; Yao, Ping; Sun, Handong; Fong, Harry H. S.; Zhang, Hongjie

    2013-01-01

    As part of our continuing efforts in the search for potential biologically active compounds from medicinal plants, we have isolated 18 compounds including two novel nitrogen containing diterpenes from extracts of the fruits of Vitex agnus-castus. These isolates, along with our previously obtained novel compound vitexlactam A (1), were evaluated for potential biological effects, including cancer chemoprevention. Chemically, the nitrogenous isolates were found to be two labdane diterpene alkaloids, each containing an α, β-unsaturated γ-lactam moiety. Structurally, they were elucidated to be 9α-hydroxy-13(14)-labden-16,15-amide (2) and 6β-acetoxy-9α-hydroxy-13(14)-labden-15,16-amide (3), which were named vitexlactams B and C, respectively. The 15 known isolates were identified as vitexilactone (4), rotundifuran (5), 8-epi-manoyl oxide (6), vitetrifolin D (7), spathulenol (8), cis-dihydro-dehydro-diconiferylalcohol-9-O-β-D-glucoside (9), luteolin-7-O-glucoside (10), 5-hydroxy-3,6,7,4′-tetramethoxyflavone (11), casticin (12), artemetin (13), aucubin (14), agnuside (15), β-sitosterol (16), p-hydroxybenzoic acid (17), and p-hydroxybenzoic acid glucose ester (18). All compound structures were determined/identified on the basis of 1D and/or 2D NMR and mass spectrometry techniques. Compounds 6, 8, 9, and 18 were reported from a Vitex spieces for the first time. The cancer chemopreventive potentials of these isolates were evaluated for NADP(H):quinone oxidoreductase type 1 (QR1) induction activity. Compound 7 demonstrated promising QR1 induction effect, while the new compound vitexlactam (3) was only slightly active. PMID:23662135

  8. 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. © 2013.

  9. Thalassiolin D: a new flavone O-glucoside Sulphate from the seagrass Thalassia hemprichii.

    PubMed

    Hawas, Usama W; Abou El-Kassem, Lamia T

    2017-10-01

    Thalassiolin D, a new flavone O-glucoside sulphate along with three flavonoids, two steroids, p-hydroxybenzoic acid, 4,4'-dihydroxybenzophenone and nitrogen compound, octopamine were isolated from the seagrass Thalassia hemprichii, collected from the Saudi Red Sea coast. By extensive spectroscopic analysis including 1D and 2D NMR and MS data, the structure of the new compound was elucidated as diosmetin 7-O-β-glucosyl-2″-sulphate. The new compound displayed moderately in vitro antiviral HCV protease activity with IC 50 value 16 μM.

  10. Modeling impacts of cold climates on vehicle emissions : final report.

    DOT National Transportation Integrated Search

    2017-01-20

    Vehicle emissions include carbon monoxide (CO), nitrogen oxides (NOx = NO + NO2), volatile organic compounds (VOCs), and air toxics such as benzene. Each of these pollutants is linked to adverse human health effects. To evaluate the contributions of ...

  11. 7 CFR 1466.4 - National priorities.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... statutory resource concerns that include soil, water, wildlife, air quality, and related resource concerns..., nitrogen oxides, volatile organic compounds, and ozone precursors and depleters that contribute to air quality impairment violations of National Ambient Air Quality Standards; (4) Reduction in soil erosion and...

  12. 7 CFR 1466.4 - National priorities.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... statutory resource concerns that include soil, water, wildlife, air quality, and related resource concerns..., nitrogen oxides, volatile organic compounds, and ozone precursors and depleters that contribute to air quality impairment violations of National Ambient Air Quality Standards; (4) Reduction in soil erosion and...

  13. 7 CFR 1466.4 - National priorities.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... statutory resource concerns that include soil, water, wildlife, air quality, and related resource concerns..., nitrogen oxides, volatile organic compounds, and ozone precursors and depleters that contribute to air quality impairment violations of National Ambient Air Quality Standards; (4) Reduction in soil erosion and...

  14. 7 CFR 1466.4 - National priorities.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... statutory resource concerns that include soil, water, wildlife, air quality, and related resource concerns..., nitrogen oxides, volatile organic compounds, and ozone precursors and depleters that contribute to air quality impairment violations of National Ambient Air Quality Standards; (4) Reduction in soil erosion and...

  15. 7 CFR 1466.4 - National priorities.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... statutory resource concerns that include soil, water, wildlife, air quality, and related resource concerns..., nitrogen oxides, volatile organic compounds, and ozone precursors and depleters that contribute to air quality impairment violations of National Ambient Air Quality Standards; (4) Reduction in soil erosion and...

  16. 40 CFR 62.9350 - Identification of plan.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... plan was officially submitted as follows: (1) Control of fluoride emissions from phosphate fertilizer... August 9, 1982. (4) Control of metals, acid gases, organic compounds and nitrogen oxide emissions from..., organic compounds, particulates and nitrogen oxide emissions from existing Hospital/Medical/Infectious...

  17. Microbial denitrogenation of fossil fuels.

    PubMed

    Benedik, M J; Gibbs, P R; Riddle, R R; Willson, R C

    1998-09-01

    The microbial degradation of nitrogen compounds from fossil fuels is important because of the contribution these contaminants make to the formation of nitrogen oxides (NOx) and hence to air pollution and acid rain. They also contribute to catalyst poisoning during the refining of crude oil, thus reducing process yields. We review the current status of microbial degradation of aromatic nitrogen compounds and discuss the potential of microbial processes to alleviate these problems.

  18. Measurement of Total Reactive Nitrogen (Nr) during the FIREX 2016 Lab Study

    NASA Astrophysics Data System (ADS)

    Roberts, J. M.; Liu, Y.; Stockwell, C.; Warneke, C.; Coggon, M.; Franchin, A.; Gilman, J.; De Gouw, J. A.; Jimenez, J. L.; Koss, A.; Krechmer, J. E.; Lerner, B. M.; Middlebrook, A. M.; Sekimoto, K.; Selimovic, V.; Yokelson, R. J.; Yuan, B.; Zarzana, K. J.; Brown, S. S.

    2017-12-01

    Wildfire is a significant source of nitrogen-containing gases and particles to the atmosphere. In addition, a warmer and drier climate is making wildfire an emerging air quality issue in North America. The nitrogen compounds emitted from biomass fires come solely from fuel nitrogen, as a result of pyrolytic and combustion processes, and range from highly reduced (NH3) to highly oxidized (HNO3/NO3-) species. A systematic understanding of the emissions and fate of these compounds is key to quantifying and predicting the role of wild fire in ozone and particle formation, so that wildfire management can be optimized. In addition, many wildfire-derived compounds have unique health impacts that also need to be managed. We have developed a method for the measurement of Total Reactive Nitrogen (Nr = all N-compounds except for N2 and N2O), based on catalytic conversion on a high temperature platinum catalyst, with detection by NO-O3 chemiluminescence. This instrument was fielded during the 2016 FIREX emissions studies at the USFS Missoula, MT., Fire Laboratory, along with a whole suite of measurements of individual gas and particle-phase species. The nitrogen balance of measured emissions will be discussed in the context of fuel-N, fuel type and fire phase (e.g. pyrolysis, flaming, smoldering stages).

  19. Rodent repellents: Preparation and properties of thiouronium compounds and cyclic imides

    USGS Publications Warehouse

    Bellack, E.; DeWitt, J.B.

    1954-01-01

    Syntheses and bioassays of cyclic imides and thiouronium compounds were carried out as part of a search for materials capable of preventing rodent damage to packaged commodities. Previous studies had shown that repellent activity was associated with functional groups containing nitrogen and sulfur, and was enhanced by the presence of ionic linkages. Twenty-seven thiouronium compounds and 40 imides, including 1 0 compounds not described previously, were prepared for these tests. Ten imides and 26 thiouronium compounds were repellent under the conditions of test. Information obtained in these studies will be utilized in the development and selection of more effective materials for prevention of rodent damage to foods and other commodities.

  20. Understanding chemistry behind secondary aerosol production from nitrogen and sulfur compounds from agriculture

    USDA-ARS?s Scientific Manuscript database

    Agricultural emissions impact particulate mass concentrations through both primary and secondary processes. Evidence from laboratory and field work suggest that not only does ammonia produce secondary particulate matter, but nitrogen and sulfur containing volatile organic compounds also contribute. ...

  1. Seasonal and annual variations and regional characteristics of wet and dry deposition amounts in East Asian region

    NASA Astrophysics Data System (ADS)

    Sato, K.; Tsuyoshi, O.; Endo, T.; Yagoh, H.; Matsuda, K.

    2011-12-01

    Emission of sulfur and nitrogen compounds in Asian region has been remarkably increased with recent rapid economical growth (Ohara et al., 2007). To appropriately assess the influence of air pollutants on the ecosystem, it is important to quantitatively determine the atmospheric deposition of air pollutants. Here, Seasonal and annual variations and regional characteristics of estimated wet and dry deposition amounts at 27 monitoring sites of Acid Deposition Monitoring Network in East Asia (EANET) from 2003 to 2009 are discussed. Wet deposition sample was collected every 24 hours or 1 week by a wet only sampler. Wet deposition amounts were calculated by the product of the volume-weighted concentrations of ionic species (SO42-, NO3-, and NH4+) in the precipitation and precipitation amount measured by a standard rain gauge at each site. Dry deposition amount was estimated by the inferential method which was originated the model developed by Wesely and Hicks (1977) and modified by Matsuda (2008). The components examined for dry deposition were sulfur compounds (gaseous SO2 and particulate SO42-) and nitrogen compounds (gaseous HNO3 and NH3, particulate NO3- and NH4+). Dry deposition was calculated by the product of the deposition velocity estimated by the inferential method for forest and grass surfaces and the monitored air concentration of each compound. The mean annual dry deposition amounts for sulfur and nitrogen compounds in Japanese sites were in the range of 5-37 and 7-50 mmol m-2 year-1, respectively. The regional characteristics of dry deposition amounts in Japan were similar between sulfur and nitrogen compounds, which showed higher deposition in the Sea of Japan side and the western Japan. The mean annual total (wet + dry) deposition amounts for sulfur and nitrogen compounds in Japanese sites were in the range of 28-77 and 22-130 mmol m-2 year-1, respectively. The contributions of dry deposition to the total deposition amounts were 10-55% and 13-56% for sulfur and nitrogen compounds, respectively. The regional characteristic of total deposition in Japan was different between sulfur and nitrogen compounds, which showed higher total deposition amounts for sulfur compounds at remote sites caused by long-range transboundary air pollution. When it is focused on the annual trend, the total deposition amounts of sulfur and nitrogen compounds increased remarkably at some sites in Japan, especially in the coast of Sea of Japan. Average dry and wet deposition amounts of sulfur or nitrogen compounds among Japanese EANET sites, 78 CASTNET sites in USA and 2447 EMEP domain grids in Europe were compared. Averages of total S (54 mmol m-2 year-1) and N (77 mmol m-2 year-1) deposition amounts in Japanese sites were larger than those in CASTNET and EMEP because of remarkably high wet deposition amounts. Especially, the higher deposition amounts of sulfur compounds in Japan were possibly caused by the long-range transboundary air pollution and natural emission sources, such as volcanic eruptions in the Japanese Archipelago. The recently increasing SO2 and NOx emissions in East Asian region would cause higher atmospheric depositions in Japan than those in other networks.

  2. High-Temperature Syntheses of New, Thermally-Stable Chemical Compounds.

    DTIC Science & Technology

    SYNTHESIS(CHEMISTRY), HEAT RESISTANT PLASTICS, NITRILES, FLUORINE COMPOUNDS, COMPLEX COMPOUNDS, NITROGEN, SULFIDES, ORGANOMETALLIC COMPOUNDS, ORGANOBORANES, BORIDES, SPINEL, CARBIDES, NITRIDES, SILICIDES .

  3. Hydrogeology and water quality of a surficial aquifer underlying an urban area, Manchester, Connecticut

    USGS Publications Warehouse

    Mullaney, John R.; Grady, Stephen J.

    1997-01-01

    The quality of water along flowpaths in a surficial aquifer system in Manchester, Connecticut, was studied during 1993-95 as part of the National Water Quality Assessment program. The flowpath study examined the relations among hydrogeology, land-use patterns, and the presence of contaminants in a surficial aquifer in an urban area, and evaluated ground water as a source of contamination to surface water. A two-dimensional, finite-difference groundwater- flow model was used to estimate travel distance, which ranged from about 50 to 11,000 feet, from the source areas to the sampled observation wells. Land use, land cover, and population density were determined in the source areas delineated by the ground-water-flow simulation. Source areas to the wells contained either high- or medium-density residential areas, and population density ranged from 629 to 8,895 people per square mile. Concentrations of selected inorganic constituents, including sodium, chloride, and nitrite plus nitrate nitrogen, were higher in the flowpath study wells than in wells in undeveloped areas with similar aquifer materials. One or more of 9 volatile organic compounds were detected at 12 of 14 wells. The three most commonly detected volatile organic compounds were chloroform, methyl-tert-butyl ether, and trichloroethene. Trichloroethene was detected at concentrations greater than the maximum contaminant level for drinking water (5 micrograms per liter) in samples from one well. Four pesticides, including dichloro diphenyl dichloroethylene, dieldrin, dichloroprop, and simazine were detected at low concentrations. Concentrations of sodium and chloride were higher in samples collected from wells screened in the top of the saturated zone than in samples collected from deeper zones. Volatile organic compounds and elevated concentrations of nitrite plus nitrate as nitrogen were detected at depths of as much as 60 feet below the water table, indicating that the effects of human activities on the ground-water quality extends to the bottom of the surficial aquifer. The age of ground water, as determined by tritium and 3helium concentrations, was 0.9 to 22.6 years. pH, alkalinity, and calcium were higher and concentrations of dissolved oxygen were lower in ground-water samples with ages of 10 years or more than in samples younger than 10 years. In addition, concentrations of sodium, chloride, and nitrite plus nitrate nitrogen were low in ground-water samples with ages of 10 years or more, indicating that concentrations of these compounds may be increasing with time or that the recharge areas to these wells may have had less intensive urban land use. Methyl-tert-butyl ether was detected only in wells with ground water ages of less than 11 years, which is consistent with the date of introduction of this compound as a gasoline additive in Connecticut. Analysis of additional samples collected for analysis of stable nitrogen isotopes indicated that the most likely source of elevated concentrations of nitrate nitrogen was lawn and garden fertilizers, but other sources, including wastewater effluents, soil organic nitrogen, and atmospheric deposition, may contribute to the total. Population density was positively correlated (at the 97 percent confidence level) to concentrations of nitrite plus nitrate as nitrogen. Water quality in the Hockanum River aquifer has been degraded by human activities, and, after discharge to surface water, affects the water quality in the Hockanum River. On an annual basis, ground-water discharge from the study area to the river (as measured at a downstream continuous-record gaging station) contributes about 5 percent of the annual load of nitrite plus nitrate nitrogen, but, during low flow, contributes 11 percent of the nitrite plus nitrate nitrogen, 32 percent of the calcium, and 16 percent of the chloride to the river.

  4. Hexacoordinated nitrogen(V) stabilized by high pressure

    PubMed Central

    Kurzydłowski, Dominik; Zaleski-Ejgierd, Patryk

    2016-01-01

    In all of its known connections nitrogen retains a valence shell electron count of eight therefore satisfying the golden rule of chemistry - the octet rule. Despite the diversity of nitrogen chemistry (with oxidation states ranging from + 5 to −3), and despite numerous efforts, compounds containing nitrogen with a higher electron count (hypervalent nitrogen) remain elusive and are yet to be synthesized. One possible route leading to nitrogen’s hypervalency is the formation of a chemical moiety containing pentavalent nitrogen atoms coordinated by more than four substituents. Here, we present theoretical evidence that a salt containing hexacoordinated nitrogen(V), in the form of an NF6− anion, could be synthesized at a modest pressure of 40 GPa (=400 kbar) via spontaneous oxidation of NF3 by F2. Our results indicate that the synthesis of a new class of compounds containing hypervalent nitrogen is within reach of current high-pressure experimental techniques. PMID:27808104

  5. Modeling Nitrogen Decrease in Water Lettuce Ponds from Waste Stabilization Ponds

    NASA Astrophysics Data System (ADS)

    Putri, Gitta Agnes; Sunarsih

    2018-02-01

    This paper presents about the dynamic modeling of the Water Lettuce ponds as a form of improvement from the Water Hyacinth ponds. The purpose of this paper is to predict nitrogen decrease and nitrogen transformation in Water Lettuce ponds integrated with Waste Stabilization Ponds. The model consists of 4 mass balances, namely Dissolved Organic Nitrogen (DON), Particulate Organic Nitrogen (PON), ammonium (NH4+), Nitrate and Nitrite (NOx). The process of nitrogen transformation which considered in a Water Lettuce ponds, namely hydrolysis, mineralization, nitrification, denitrification, plant and bacterial uptake processes. Numerical simulations are performed by giving the values of parameters and the initial values of nitrogen compounds based on a review of previous studies. Numerical results show that the rate of change in the concentration of nitrogen compounds in the integration ponds of waste stabilization and water lettuce decreases and reaches stable at different times.

  6. Analysis of water and nitrogen use efficiency for maize (Zea mays L.) grown on soft rock and sand compound soil.

    PubMed

    Wang, Huanyuan; Han, Jichang; Tong, Wei; Cheng, Jie; Zhang, Haiou

    2017-06-01

    Maize was grown on compound soils constituted from mixtures of soft rock and sand at different ratios, and water use efficiency (WUE), nitrogen use efficiency (NUE) and fertilizer nitrogen use efficiency (FNUE) were quantified. The data were used to assist in designing strategies for optimizing water and nitrogen management practices for maize on the substrates used. Maize was sown in composite soil prepared at three ratios of soft rock and sand (1:1, 1:2 and 1:5 v/v) in Mu Us Sandy Land, Yuyang district, Yulin city, China. Yields, amount of drainage, nitrogen (N) leaching, WUE and NUE were calculated. Then a water and nitrogen management model (WNMM) was calibrated and validated. No significant difference in evapotranspiration of maize was found among compound soils with soft rock/sand ratios of 1:1, 1:2 and 1:5, while water drainage increased significantly with increasing soft rock/sand ratio. WUE increased to 1.30 kg m -3 in compound soil with 1:2 soft rock/sand ratio. Nitrogen leaching and ammonia volatilization were the main reason for nitrogen loss, and N reduction mainly relied on crop uptake. NUE and FNUE could reach 33.1 and 24.9 kg kg -1 N respectively. Water drainage and nitrogen leaching occurred mostly during heavy rainfall or irrigation. Through a scenario analysis of different rainfall types, water and fertilizer management systems were formulated each year. This study shows that soft rock plays a key role in improving the WUE, NUE and FNUE of maize. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

  7. Spectrophotometric Determination of Nitrogen Oxides in the Air with 2-N-Ethyl-5-Naphthol-7-Sulfonic Acid

    NASA Astrophysics Data System (ADS)

    Huang, Y.; Shi, W.; Zhang, C.; Wen, H.

    2017-09-01

    For the determination of nitrogen oxides in the air, the structure of diazo and coupling compounds was studied and tested by experiments. The conditions and methods of diazo and coupling reactions were investigated. Furthermore, a spectrophotometric method using sulfanilamide as a diazo compound and 2-N-ethyl-5-naphthol-7-sulfonic acid (N-ethyl J acid) as a coupling compound was proposed. The maximum absorption wavelength of sulfanilamide-Nethyl J acid azo compound was at 478 nm. The molar absorptivity was 4.31 × 104 L/(mol × cm) with a recovery of 98.7-100.9% and RSD of 1.85%. For nitrogen oxides, the determinate limit of this measurement was 0.015 mg/m3 and the determinate range 0.024-2.0 mg/m3. Moreover, a high degree of correlation was observed between the results obtained by the proposed method and the standard methods. The proposed method can be easily applied to determine nitrogen oxides in the air.

  8. β-Lactam Ring Opening: A Useful Entry to Amino Acids and Relevant Nitrogen-Containing Compounds

    NASA Astrophysics Data System (ADS)

    Palomo, C.; Oiarbide, M.

    The main strategies for the ring opening of β-lactams by chemical means are described. The discovery of each approach is put into context, sometimes in connection to processes occurring in biological systems, and the synthetic opportunities each approach offers are shown. Thus, this β-lactam route affords a number of synthetically relevant building-blocks, including α-amino acids, β-amino acids, their derived peptides, and other nitrogen containing heterocycles and open chain molecules. The content, which encompases references to initial work, further major development, and the most relevant recent literature contributions, is categorized according to the ring bond cleavaged (N 1-C 2, C 2-C 3, C 3 -C 4 , N 1-C 4), to finish with ring opening strategies leading to large heterocyclic compounds. Within each category, distinction has been made according to the type of nucleophilic agent employed, principally O-, N-, and C-nucleophiles. Also, a variety of applications of the strategy to the synthesis of interesting target compounds are shown.

  9. 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 formation was significantly enhanced when the night-time oxidation was performed in the presence of both neutral seed particle and gas-phase SO2, suggesting that the presence of gas-phase SO2 is a key for their formation.

  10. Nitrogen and Oxygen Photochemistry following SL9

    NASA Technical Reports Server (NTRS)

    Moses, Julianne I.; Allen, Mark; Gladstone, G. Randall

    1995-01-01

    The collision of Shoemaker Levy 9 (SL9) with Jupiter caused many new molecular species to be deposited in the Jovian stratosphere. We use a photochemical model to follow the evolution of the impact derived species. Our results regarding the nitrogen and oxygen compounds are presented here. NH3 photolysis initiates the nitrogen photochemistry. Much of the nitrogen ends up in N2, nitrogen-sulfur compounds, and HCN, but NH3 and nitriles such as C2H3CN may also exist in observable quantities for a year or so after the impacts. Oxygen species survive for a long time in the Jovian stratosphere. The only major oxygen containing compounds that exhibit dramatic changes in the lower stratosphere in the first year following the impacts are SO, SO2, and OCS - H2O, CO2, and CO are comparatively stable. We discuss the important photochemical processes operating on the nitrogen and oxygen species in the Jovian stratosphere, make prediction concerning the temporal variation of the major species, and identify molecules that might act as good tracers for atmospheric dynamics.

  11. A Novel Anoxic Pathway for Urea and Cyanate in Marine Oxygen Deficient Zones Revealed by Combined Microbiological and Biogeochemical Tools

    NASA Astrophysics Data System (ADS)

    Widner, B.; Fuchsman, C. A.; Babbin, A. R.; Ji, Q.; Mulholland, M. R.

    2016-02-01

    Urea and cyanate are reduced nitrogen compounds that can serve as nitrogen and carbon sources for marine microbes, and cyanate forms from decomposition of urea. Some marine bacteria, including cyanobacteria, possess genes encoding an ABC-type cyanate transporter and an intracellular cyanate hydratase, and genes for urea uptake and assimilation are widespread. To investigate cyanate distribution and availability in the ocean, we recently developed a nanomolar cyanate assay specific to seawater. In an oxygenated water column, urea and cyanate concentrations are generally low in surface waters and exhibit a concentration maximum near the base of the euphotic zone likely due to production from organic matter degradation. Below the euphotic zone, urea and cyanate concentrations decrease, likely due to oxidation reactions. It has been suggested that simple organic nitrogen compounds may support anaerobic ammonium oxidation (anammox) in oxygen deficient zones (ODZs). We mapped urea and cyanate distributions and used stable isotope-labeled urea and cyanate to measure their potential support of anammox and their uptake within the Eastern Tropical North and South Pacific ODZs. We also employed metagenomic techniques to determine the abundance and distribution of genes for the uptake and assimilation of urea and cyanate. The combined data indicate that, in ODZs, urea is used primarily as a nitrogen source while cyanate is used as both a nitrogen source and to generate energy.

  12. 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. © 2011 Institute of Food Technologists®

  13. Effects of Isoprene- and Toluene-Generated Smog on Allergic Inflammation in Mice

    EPA Science Inventory

    Reactions of organic compounds with nitric oxide (NO) and sunlight produce complex mixtures of pollutants including secondary organic aerosol (SOA), ozone (O3), nitrogen dioxide (NO2), and reactive aldehydes. The health effects of these photochemical smog mixtures in susceptible ...

  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. Effects of UV-B radiation on growth, photosynthesis, UV-B-absorbing compounds and NADP-malic enzyme in bean (Phaseolus vulgaris L.) grown under different nitrogen conditions.

    PubMed

    Pinto, M E; Casati, P; Hsu, T P; Ku, M S; Edwards, G E

    1999-02-01

    The effects of UV-B radiation on growth, photosynthesis, UV-B-absorbing compounds and NADP-malic enzyme have been examined in different cultivars of Phaseolous vulgaris L. grown under 1 and 12 mM nitrogen. Low nitrogen nutrition reduces chlorophyll and soluble protein contents in the leaves and thus the photosynthesis rate and dry-matter accumulation. Chlorophyll, soluble protein and Rubisco contents and photosynthesis rate are not significantly altered by ambient levels of UV-B radiation (17 microW m-2, 290-320 nm, 4 h/day for one week). Comparative studies show that under high nitrogen, UV-B radiation slightly enhances leaf expansion and dry-matter accumulation in cultivar Pinto, but inhibits these parameters in Vilmorin. These results suggest that the UV-B effect on growth is mediated through leaf expansion, which is particularly sensitive to UV-B, and that Pinto is more tolerant than Vilmorin. The effect of UV-B radiation on UV-B-absorbing compounds and on NADP-malic enzyme (NADP-ME) activity is also examined. Both UV-B radiation and low-nitrogen nutrition enhance the content of UV-B-absorbing compounds, and among the three cultivars used, Pinto exhibits the highest increases and Arroz the lowest. The same trend is observed for the specific activity and content of NADP-ME. On a leaf-area basis, the amount of UV-B-absorbing compounds is highly correlated with the enzyme activity (r2 = 0.83), suggesting that NADP-ME plays a key role in biosynthesis of these compounds. Furthermore, the higher sensitivity of Vilmorin than Pinto to UV-B radiation appears to be related to the activity of NADP-ME and the capacity of the plants to accumulate UV-B-absorbing compounds.

  16. Astrobiological Implications of Titan Tholin in Methane Lakes

    NASA Astrophysics Data System (ADS)

    Khare, Bishun N.; McKay, C. P.; McPherson, S.; Cruikshank, D.; Nna-Mvondo, D.; Sekine, Y.

    2010-10-01

    We report here on our ongoing research in the Laboratory for Planetary Studies at NASA Ames Research Center dedicated to determine the degree of solubility of Titan tholin in the methane-ethane lakes. Our work is also directed toward confirming the presence of any astrobiologically significant molecules via hydrolysis and pyrolysis of a simulated lake sample. Our previous work conducted at Cornell University and subsequently in the Laboratory for Planetary Studies at NASA Ames Research Center has established that Titan tholin produces amino acids (Khare et al. Icarus 1986) on hydrolysis, and many compounds including adenine on pyrolysis (Khare et al. Adv. Space Res. 1984). Also, our previous work by Thompson et al. (Icarus 1991) has clearly indicated that when energy is supplied to Titan's atmospheric composition (methane and nitrogen), tholin results from hundreds of contemporary compounds, including highly reactive compounds such as azides and isocyanides. Cassini showed that photolysis of methane produces benzene and many polycyclic aromatic hydrocarbons, along with compounds with very high molecular weights (up to 10000 amu), resulting from the photolytic reactions of CH4 with nitrogen. These heavy aerosols, termed "tholins” by Sagan and Khare (Nature 1979), are also synthesized when Titan intercepts charged particles from the magnetosphere of Saturn. Tholins resulting from both of these syntheses eventually descend to the surface of Titan, where some quantity collects in the methane-ethane lakes. This research is supported by a grant from Planetary Atmospheres.

  17. 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.

  18. 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...

  19. A role for the diazotrophic cyanobacterium, Cyanothece sp. strain ATCC 51142, in nitrogen cycling for CELSS applications.

    PubMed

    Schneegurt, M A; Sherman, L A

    1996-01-01

    Simple calculations show that fixed nitrogen regeneration in a CELSS may not be as efficient as stowage and resupply of fixed nitrogen compounds. However, fixed nitrogen regeneration may be important for the sustainability and safety of a deployed CELSS. Cyanothece sp. strain ATCC 51142, a unicellular, aerobic, diazotrophic cyanobacterium, with high growth rates and a robust metabolism, is a reasonable candidate organism for a biological, fixed nitrogen regeneration system. In addition, Cyanothece sp. cultures may be used to balance gas exchange ratio imparities between plants and humans. The regeneration of fixed nitrogen compounds by cyanobacterial cultures was examined in the context of a broad computer model/simulation (called CELSS-3D). When cyanothece sp. cultures were used to balance gas exchange imparities, the biomass harvested could supply as much as half of the total fixed nitrogen needed for plant biomass production.

  20. Relationship between electronic properties and drug activity of seven quinoxaline compounds: A DFT study

    NASA Astrophysics Data System (ADS)

    Behzadi, Hadi; Roonasi, Payman; Assle taghipour, Khatoon; van der Spoel, David; Manzetti, Sergio

    2015-07-01

    The quantum chemical calculations at the DFT/B3LYP level of theory were carried out on seven quinoxaline compounds, which have been synthesized as anti-Mycobacterium tuberculosis agents. Three conformers were optimized for each compound and the lowest energy structure was found and used in further calculations. The electronic properties including EHOMO, ELUMO and related parameters as well as electron density around oxygen and nitrogen atoms were calculated for each compound. The relationship between the calculated electronic parameters and biological activity of the studied compounds were investigated. Six similar quinoxaline derivatives with possible more drug activity were suggested based on the calculated electronic descriptors. A mechanism was proposed and discussed based on the calculated electronic parameters and bond dissociation energies.

  1. Cyathane diterpenoids and nitrogenous terphenyl derivative from the fruiting bodies of basidiomycete Phellodon niger.

    PubMed

    Fang, Sheng-Tao; Zhang, Ling; Li, Zheng-Hui; Li, Bo; Liu, Ji-Kai

    2010-09-01

    Two new cyathane-type diterpenoids, nigernin A and B (1, 2), one new nitrogenous terphenyl derivative, phellodonin (3), together with three known compounds, 2',3'-diacetoxy-3,4,5',6',4''-pentahydroxy-p-terphenyl, grifolin, and 4-O-methylgrifolic acid, were isolated from the fruiting bodies of basidiomycete Phellodon niger. The structures of these new compounds were elucidated by spectroscopic methods and comparison with the data of known compounds in the literature. All these compounds were isolated from this fungus for the first time.

  2. Indoor Air Quality in Schools (IAQ): The Importance of Monitoring Carbon Dioxide Levels.

    ERIC Educational Resources Information Center

    Sundersingh, David; Bearg, David W.

    This article highlights indoor air quality and exposure to pollutants at school. Typical air pollutants within schools include environmental tobacco smoke, formaldehyde, volatile organic compounds, nitrogen oxides, carbon monoxide, carbon dioxide, allergens, pathogens, radon, pesticides, lead, and dust. Inadequate ventilation, inefficient…

  3. Ebselen reduces the toxicity of mechlorethamine in A-431 cells via inhibition of apoptosis.

    PubMed

    Lulla, Anju; Pino, Maria A; Piętka-Ottlik, Magdalena; Młochowski, Jacek; Sparavalo, Oleksiy; Billack, Blase

    2013-06-01

    A series of test compounds were evaluated for an ability to reduce the toxicity of the nitrogen mustard mechlorethamine (HN2) in vitro. The test compounds included resveratrol, pterostilbene, vitamin C, ebselen, ebselen diselenide, and ebselen-sulfur. Among them, ebselen demonstrated the highest degree of protection against HN2 toxicity. To this end, pretreatment of the cells with ebselen offered protection against the toxicant whereas no protection was observed when cells were first incubated with HN2 and then treated with ebselen. Significant increases in caspase 3 and caspase 9 activities were observed in response to HN2, and ebselen was found to reduce these effects. Taken together, the data presented here indicate that ebselen is an effective countermeasure to nitrogen mustard in vitro, which is worthy of future investigation in vivo. © 2013 Wiley Periodicals, Inc.

  4. Exogenous Glycine Nitrogen Enhances Accumulation of Glycosylated Flavonoids and Antioxidant Activity in Lettuce (Lactuca sativa L.).

    PubMed

    Yang, Xiao; Cui, Xiaoxian; Zhao, Li; Guo, Doudou; Feng, Lei; Wei, Shiwei; Zhao, Chao; Huang, Danfeng

    2017-01-01

    Glycine, the simplest amino acid in nature and one of the most abundant free amino acids in soil, is regarded as a model nutrient in organic nitrogen studies. To date, many studies have focused on the uptake, metabolism and distribution of organic nitrogen in plants, but few have investigated the nutritional performance of plants supplied with organic nitrogen. Lettuce ( Lactuca sativa L.), one of the most widely consumed leafy vegetables worldwide, is a significant source of antioxidants and bioactive compounds such as polyphenols, ascorbic acid and tocopherols. In this study, two lettuce cultivars, Shenxuan 1 and Lollo Rossa, were hydroponically cultured in media containing 4.5, 9, or 18 mM glycine or 9 mM nitrate (control) for 4 weeks, and the levels of health-promoting compounds and antioxidant activity of the lettuce leaf extracts were evaluated. Glycine significantly reduced fresh weight compared to control lettuce, while 9 mM glycine significantly increased fresh weight compared to 4.5 or 18 mM glycine. Compared to controls, glycine (18 mM for Shenxuan 1; 9 mM for Lollo Rossa) significantly increased the levels of most antioxidants (including total polyphenols, α-tocopherol) and antioxidant activity, suggesting appropriate glycine supply promotes antioxidant accumulation and activity. Glycine induced most glycosylated quercetin derivatives and luteolin derivatives detected and decreased some phenolic acids compared to nitrate treatment. This study indicates exogenous glycine supplementation could be used strategically to promote the accumulation of health-promoting compounds and antioxidant activity of hydroponically grown lettuce, which could potentially improve human nutrition.

  5. Optimization of fertilization characteristics of urine by addition of Nitrosomonas europaea bio-seed.

    PubMed

    Hashemi, Shervin; Han, Mooyoung; Kim, Tschungil

    2016-10-01

    Because of the high concentration of nutrients in human urine, its utilization as an organic fertilizer has been notable throughout history. However, the nitrogen compounds in urine are not stable. Therefore, to convert urine into a suitable fertilizer, it is important to stabilize and adjust unstable nitrogen compounds such as ammonia. Because nitrification can influence the nitrogen profile, the use of nitrifying microorganisms can be useful for stabilizing the nitrogen profile of urine. This study investigated the changes in nitrogen compounds in pure urine and examined the effect of adding Nitrosomonas europaea bio-seed solution on these changes. It was found that the addition of bio-seed could reduce nitrogen loss as well as the time required to stabilize the nitrogen profile. Furthermore, the optimum concentration of bio-seed (6 × 10(5) N. europaea cells L(-1) ) that not only leads to the least nutrient loss but also results in an adequate nitrate/ammonium ratio and regulates the amount of nitrate produced, thereby preventing over-fertilization, was determined. At this concentration, no dilution or dewatering is required, thus minimizing water and energy consumption. Usage of the optimum of concentration of bio-seed will also eliminate the need for inorganic chemical additives. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

  6. Air Quality Criteria for Oxides of Nitrogen (Final Report, 1993)

    EPA Science Inventory

    This criteria document focuses on a review and assessment of the effects on human health and welfare of the nitrogen oxides, nitric oxide (NO) and nitrogen dioxide (NO2), and the related compounds, nitrites, nitrates, nitrogenous acids, and nitrosamines. Although the emphasis is ...

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

    DOE Office of Scientific and Technical Information (OSTI.GOV)

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

    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,more » 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.« less

  8. Mesoporous nitrogen-doped carbon microfibers derived from Mg-biquinoline-dicarboxy compound for efficient oxygen electroreduction

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Kong, Aiguo, E-mail: agkong@chem.ecnu.edu.cn; Fan, Xiaohong; Chen, Aoling

    An in-situ MgO-templating synthesis route was introduced to obtain the mesoporous nitrogen-doped carbon microfibers by thermal conversion of new Mg-2,2′-biquinoline 4,4-dicarboxy acid coordination compound (Mg-DCA) microfibers. The investigated crystal structure of Mg-DCA testified that the assembling of Mg{sup 2+} and DCA through Mg-O coordination bond and hydrogen bond contributed to the formation of one-dimensional (1D) crystalline Mg-DCA microfibers. The nitrogen-doped carbons derived from the pyrolysis of Mg-DCA showed the well-defined microfiber morphology with high mesopore-surface area. Such mesoporous microfibers exhibited the efficient catalytic activity for oxygen reduction reaction (ORR) in alkaline solutions with better stability and methanol-tolerance performance. - Graphicalmore » abstract: Mesoporous nitrogen-doped carbon microfibers with efficient oxygen electroreduction activity were prepared by thermal conversion of new Mg-biquinoline-based coordination compound microfibers.« less

  9. 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...

  10. Clandestine grave detector

    DOEpatents

    Andrews, Jr., William H.; Thompson, Cyril V [Knoxville, TN; Vass, Arpad A [Oak Ridge, TN; Smith, Rob R [Knoxville, TN

    2011-12-13

    An apparatus and a method for detecting a burial site of human remains are disclosed. An air stream is drawn through an air intake conduit from locations near potential burial sites of human remains. The air stream is monitored by one or more chemical sensors to determine whether the air stream includes one or more indicator compounds selected from halogenated compounds, hydrocarbons, nitrogen-containing compounds, sulfur-containing compounds, acid/ester compounds, oxygen-containing compounds, and naphthalene-containing compounds. When it is determined that an indicator compound is present in the air stream, this indicates that a burial site of human remains is below or nearby. Each sensor may be in electrical communication with an indicator that signals when the sensor has detected the presence of the indicator compound in the air stream. In one form, the indicator compound is a halogenated compound and/or a hydrocarbon, and the presence of the halogenated compound and/or the hydrocarbon in the air stream indicates that a burial site of human remains is below or nearby.

  11. Microfabricated thermionic detector

    DOEpatents

    Lewis, Patrick R; Manginell, Ronald P; Wheeler, David R; Trudell, Daniel E

    2012-10-30

    A microfabricated TID comprises a microhotplate and a thermionic source disposed on the microhotplate. The microfabricated TID can provide high sensitivity and selectivity to nitrogen- and phosphorous-containing compounds and other compounds containing electronegative function groups. The microfabricated TID can be microfabricated with semiconductor-based materials. The microfabricated TID can be combined with a microfabricated separation column and used in microanalytical system for the rapid on-site detection of pesticides, chemical warfare agents, explosives, pharmaceuticals, and other organic compounds that contain nitrogen or phosphorus.

  12. A nitrous acid biosynthetic pathway for diazo group formation in bacteria.

    PubMed

    Sugai, Yoshinori; Katsuyama, Yohei; Ohnishi, Yasuo

    2016-02-01

    Although some diazo compounds have bioactivities of medicinal interest, little is known about diazo group formation in nature. Here we describe an unprecedented nitrous acid biosynthetic pathway responsible for the formation of a diazo group in the biosynthesis of the ortho-diazoquinone secondary metabolite cremeomycin in Streptomyces cremeus. This finding provides important insights into the biosynthetic pathways not only for diazo compounds but also for other naturally occurring compounds containing nitrogen-nitrogen bonds.

  13. Identification of NH4+-regulated genes of Herbaspirillum seropedicae by random insertional mutagenesis.

    PubMed

    Schwab, Stefan; Ramos, Humberto J; Souza, Emanuel M; Pedrosa, Fábio O; Yates, Marshall G; Chubatsu, Leda S; Rigo, Liu U

    2007-05-01

    Random mutagenesis using transposons with promoterless reporter genes has been widely used to examine differential gene expression patterns in bacteria. Using this approach, we have identified 26 genes of the endophytic nitrogen-fixing bacterium Herbaspirillum seropedicae regulated in response to ammonium content in the growth medium. These include nine genes involved in the transport of nitrogen compounds, such as the high-affinity ammonium transporter AmtB, and uptake systems for alternative nitrogen sources; nine genes coding for proteins responsible for restoring intracellular ammonium levels through enzymatic reactions, such as nitrogenase, amidase, and arginase; and a third group includes metabolic switch genes, coding for sensor kinases or transcription regulation factors, whose role in metabolism was previously unknown. Also, four genes identified were of unknown function. This paper describes their involvement in response to ammonium limitation. The results provide a preliminary profile of the metabolic response of Herbaspirillum seropedicae to ammonium stress.

  14. 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. Copyright © 2013 Elsevier Ltd. All rights reserved.

  15. Distribution of Nitrogen Compounds in Marine Aerosol and Their Deposition Over the Pacific Ocean

    NASA Astrophysics Data System (ADS)

    Uematsu, M.; Narita, Y.; Sun, S. Y.

    2016-02-01

    Nutrient supply to the ocean surface layer is an important factor controlling the marine ecosystem. The major paths of supplies of nutrients have been considered as those from nutrient-rich deep waters and riverine input, which is mostly taken up near the estuary region, but the nutrients transported through the atmosphere recognize to be important for the open ocean, where the nutrients are limiting primary productivity. Because of rapid economic development surrounding the Pacific Ocean, anthropogenic NOx emissions increased by 2-3 times during the past decades. This rapid increase of NOx emission causes a large amount of N deposition mostly in the form of nitrate and ammonium over ocean surfaces, and strongly impacts their marine ecosystems. Especially, biological N2 fixation, riverine input and atmospheric deposition contribute to support "new production" and affect CO2 air-sea exchange. The concentration of nitrogen compounds in marine aerosol has been measured on the island stations and onboard of research vessels in the Pacific Ocean over a few decades. The temporal and spatial atmospheric distribution of water-soluble particulate nitrogen compounds is summarized in this study. As the transport of anthropogenic nitrogen compounds from land, high concentration is revealed over the marginal seas in the western North Pacific. Most of nitrate exists in the coarse aerosol associated with sea-salt particle while ammonium exists in the fine particle and showing a good relationship with non-sea-salt sulfate. This different particle size affects to estimate the deposition flux of nitrogen compounds to the ocean surface. Over the high primary productive areas such as the equatorial Pacific and the Southern Ocean, ammonia is released into the atmosphere and transported to other area. By wet and dry deposition, ammonium is removed to the ocean surface and modified the distribution of nitrogen compounds in the surface waters.

  16. Characterization of sulfur and nitrogen compounds in Brazilian petroleum derivatives using ionic liquid capillary columns in comprehensive two-dimensional gas chromatography with time-of-flight mass spectrometric detection.

    PubMed

    Cappelli Fontanive, Fernando; Souza-Silva, Érica Aparecida; Macedo da Silva, Juliana; Bastos Caramão, Elina; Alcaraz Zini, Claudia

    2016-08-26

    Diesel and naphtha samples were analyzed using ionic liquid (IL) columns to evaluate the best column set for the investigation of organic sulfur compounds (OSC) and nitrogen(N)-containing compounds analyses with comprehensive two-dimensional gas chromatography coupled to time-of-flight mass spectrometry detector (GC×GC/TOFMS). Employing a series of stationary phase sets, namely DB-5MS/DB-17, DB-17/DB-5MS, DB-5MS/IL-59, and IL-59/DB-5MS, the following parameters were systematically evaluated: number of tentatively identified OSC, 2D chromatographic space occupation, number of polyaromatic hydrocarbons (PAH) and OSC co-elutions, and percentage of asymmetric peaks. DB-5MS/IL-59 was chosen for OSC analysis, while IL59/DB-5MS was chosen for nitrogen compounds, as each stationary phase set provided the best chromatographic efficiency for these two classes of compounds, respectively. Most compounds were tentatively identified by Lee and Van den Dool and Kratz retention indexes, and spectra-matching to library. Whenever available, compounds were also positively identified via injection of authentic standards. Copyright © 2016 Elsevier B.V. All rights reserved.

  17. The nitrogen isotopic composition in soils and plants: Its use in environmental studies (A Review)

    NASA Astrophysics Data System (ADS)

    Makarov, M. I.

    2009-12-01

    The results of studying the isotopic composition of the nitrogen in soils and plants and its use for characterizing the nitrogen cycle in ecosystems, the transformation of nitrogen compounds in soils, the sources of nitrogen nutrition for plants, and the assessment of the symbiotic nitrogen fixation’s contribution to the nitrogen budget of ecosystems were considered for a wide variety of natural and agricultural ecosystems.

  18. Characterization of commercial inactive dry yeast preparations for enological use based on their ability to release soluble compounds and their behavior toward aroma compounds in model wines.

    PubMed

    Pozo-Bayón, Maria Angeles; Andujar-Ortiz, Inmaculada; Alcaide-Hidalgo, Juan María; Martín-Alvarez, Pedro J; Moreno-Arribas, M Victoria

    2009-11-25

    The characterization of commercial enological inactive dry yeast (IDY) with different applications in wine production has been carried out. This study was based on the yeast's ability to release soluble compounds (high molecular weight nitrogen, free amino nitrogen, peptidic nitrogen, free amino acids, and polysaccharides) into model wines and on its behavior toward the volatility of seven wine aroma compounds. Important differences in soluble compounds released into the model wines supplemented with commercial IDY were found, with the free amino acids being among the most released. The volatility of most of the aroma compounds was affected by the addition of IDY preparations at a concentration usually employed during winemaking. The extent of this effect was dependent on the physicochemical characteristics of the aroma compound and on the length of time the IDY preparations remained in contact with the model wines. Whereas shorter contact times (2, 4, and 6 days) mainly promoted a "salting-out" effect, longer exposure (9 and 13 days) provoked a retention effect, with the consequent reduction of aroma compounds in the headspace. The use of different commercial preparations also promoted different effects toward the aroma compounds that may be at least in part due to differences in their ability to release soluble compounds of yeast origin into the wines.

  19. Nutrient co-limited Trichodesmium as nitrogen source or sink in a future ocean.

    PubMed

    Walworth, Nathan G; Fu, Fei-Xue; Lee, Michael D; Cai, Xiaoni; Saito, Mak A; Webb, Eric A; Hutchins, David A

    2017-11-27

    Nitrogen-fixing (N 2 ) cyanobacteria provide bioavailable nitrogen to vast ocean regions but are in turn limited by iron (Fe) and/or phosphorus (P), which may force them to employ alternative nitrogen acquisition strategies. The adaptive responses of nitrogen-fixers to global-change drivers under nutrient-limited conditions could profoundly alter the current ocean nitrogen and carbon cycles. Here, we show that the globally-important N 2 -fixer Trichodesmium fundamentally shifts nitrogen metabolism towards organic-nitrogen scavenging following long-term high-CO 2 adaptation under iron and/or phosphorus (co)-limitation. Global shifts in transcripts and proteins under high CO 2 /Fe-limited and/or P-limited conditions include decreases in the N 2 -fixing nitrogenase enzyme, coupled with major increases in enzymes that oxidize trimethylamine (TMA). TMA is an abundant, biogeochemically-important organic nitrogen compound that supports rapid Trichodesmium growth while inhibiting N 2 fixation. In a future high-CO 2 ocean, this whole-cell energetic reallocation towards organic nitrogen scavenging and away from N 2 -fixation may reduce new-nitrogen inputs by Trichodesmium , while simultaneously depleting the scarce fixed-nitrogen supplies of nitrogen-limited open ocean ecosystems. Importance Trichodesmium is among the most biogeochemically-significant microorganisms in the ocean, since it supplies up to 50% of the new nitrogen supporting open ocean food webs. We used Trichodesmium cultures adapted to high CO 2 for 7 years followed by additional exposure to iron and/or phosphorus (co)-limitation. We show that 'future ocean' conditions of high CO 2 and concurrent nutrient limitation(s) fundamentally shift nitrogen metabolism away from nitrogen fixation, and instead towards upregulation of organic-nitrogen scavenging pathways. We show that Trichodesmium's responses to projected future ocean conditions include decreases in the nitrogen-fixing nitrogenase enzymes, coupled with major increases in enzymes that oxidize the abundant organic nitrogen source trimethylamine (TMA). Such a shift towards organic nitrogen uptake and away from nitrogen fixation may substantially reduce new-nitrogen inputs by Trichodesmium to the rest of the microbial community in the future high-CO 2 ocean, with potential global implications for ocean carbon and nitrogen cycling. Copyright © 2017 American Society for Microbiology.

  20. Effects of nitrogen nutrients on the volatile organic compound emissions from Microcystis aeruginosa.

    PubMed

    Zuo, Zhaojiang; Yang, Lin; Chen, Silan; Ye, Chaolin; Han, Yujie; Wang, Sutong; Ma, Yuandan

    2018-06-06

    Cyanobacteria release abundant volatile organic compounds (VOCs), which can poison other algae and cause water odor. To uncover the effects of nitrogen (N) nutrients on the formation of cyanobacteria VOCs, the cell growth, VOC emission and the expression of genes involving in VOC formation in Microcystis aeruginosa were investigated under different N conditions. With the supplement of NaNO 3 , NaNO 2 , NH 4 Cl, urea, Serine (Ser) and Arginine (Arg) as the sole N source, NaNO 3 , urea and Arg showed the best effects on M. aeruginosa cell growth, and limited N supply inhibited the cell growth. M. aeruginosa released 26, 25, 23, 27, 23 and 25 compounds, respectively, in response to different N forms, including furans, sulfocompounds, terpenoids, benzenes, hydrocarbons, aldehydes, and esters. Low-N especially Non-N condition markedly promoted the VOC emission. Under Non-N condition, four up-regulated genes involving in VOC precursor formation were identified, including the genes of pyruvate kinase, malic enzyme and phosphotransacetylase for terpenoids, the gene of aspartate aminotransferase for benzenes and sulfocompounds. In eutrophic water, cyanobacteria release different VOC blends using various N forms, and the reduction of N amount caused by cyanobacteria massive growth can promote algal VOC emission by up-regulating the gene expression. Copyright © 2018 Elsevier Inc. All rights reserved.

  1. Acute bioassays and hazard evaluation of representative contaminants detected in Great Lakes fish

    USGS Publications Warehouse

    Passino, Dora R. May; Smith, Stephen B.

    1987-01-01

    We have provided a hazard ranking for 19 classes of compounds representing many of the nearly 500 organic compounds identified by gas chromatography-mass spectrometry in lake trout (Salvelinus namaycush) and walleye (Stizostedion vitreum vitreum) from the Great Lakes and Lake St. Clair. We initially made a provisional hazard ranking based on available published and unpublished information on aquatic toxicity, bioaccumulation, occurrence and sources. Acute toxicity tests with Daphnia pulex at 17A°C in reconstituted hard water were performed with 30 compounds representative of the 19 classes that were highest in the provisional ranking. The resulting toxicity data, along with information on the compounds' occurrence in Great Lakes fish and their sources, were ranked and weighted and then used in calculating the revised hazard ranking. The 10 most hazardous classes, in descending order, are as follows (values shown are mean 48-h EC50s, in μ/ml): arene halides (e.g., polychlorinated biphenyls, DDT), 0.0011; phthalate esters, 0.133; chlorinated camphenes (toxaphene), 0.0082; polyaromatic hydrocarbons (PAHs; e.g., dimethylnaphthalene) and reduced derivatives, 1.01; chlorinated fused polycyclics (e.g., trans-nonachlor), 0.022; nitrogen-containing compounds (e.g., O-methylhydroxyl-amine), 1.35; alkyl halides (e.g., (bromomethyl)cyclohexene), 10.1; cyclic alkanes (e.g., cyclododecane), 20.9; silicon-containing compounds (e.g., dimethyldiethoxy silane), 1.25; and heterocyclic nitrogen compounds (e.g., nicotine), 2.48. We recommend that chronic bioassays be conducted with fish and invertebrates to determine the sublethal effects of the following classes of compounds, for which few toxicity data are available: PAHs, heterocyclic nitrogen compounds, other nitrogen-containing compounds, alkyl halides, cyclic alkanes and silicon-containing compounds. Information from these types of studies will aid researchers in determining the possible causal role these contaminants play in the decline and reproductive impairment of Great Lakes fish.

  2. Leaf Volatile Compounds and Associated Gene Expression during Short-Term Nitrogen Deficient Treatments in Cucumis Seedlings

    PubMed Central

    Deng, Jie; Yu, Hong-Jun; Li, Yun-Yun; Zhang, Xiao-Meng; Liu, Peng; Li, Qiang; Jiang, Wei-Jie

    2016-01-01

    Nitrogen (N) is an important macronutrient for plant growth and development, but the regulatory mechanism of volatile compounds in response to N deficiency is not well understood, especially in cucumber, which consumes excessive N during growth. In this study, the major volatile compounds from cucumber leaves subjected to N deficiency were analyzed by GC-MS. A total of 24 volatile components were identified including 15 aldehydes, two ketones, two alkenes, and five other volatile compounds in 9930 leaves. Principal component analysis using volatile compounds from cucumber leaves provided good separation between N-sufficient and N-deficient treatments. The main volatiles in cucumber leaves were found to be C6 and C9 aldehydes, especially (E)-2-hexanal and (E,Z)-2,6-nonadienal. (E)-2-hexanal belonged to the C6 aldehyde and was the most abundant compound, whereas (E,Z)-2,6-nonadienal was the chief component of C9 aldehydes. During N-deficient treatment, short-chain volatile content was significantly improved at 5 day, other volatiles displayed significant reduction or no significantly changes in all sampling points. Improvement of short-chain volatiles was confirmed in the six other inbred lines at 5 day after N-deficient treatments. The expression analysis of 12 cucumber LOX genes and two HPL genes revealed that CsLOX19, CsLOX20, and CsLOX22 had common up-regulated expression patterns in response to N-deficient stress in most inbred lines; meanwhile, most sample points of CsHPL1 also had significant up-regulated expression patterns. This research focused on the relationship between volatiles in cucumber and different nitrogen environments to provide valuable insight into the effect of cultivation and management of the quality of cucumber and contributes to further research on volatile metabolism in cucumber. PMID:27827841

  3. Effect of two doses of urea foliar application on leaves and grape nitrogen composition during two vintages.

    PubMed

    Pérez-Álvarez, Eva P; Garde-Cerdán, Teresa; García-Escudero, Enrique; Martínez-Vidaurre, José María

    2017-06-01

    Nitrogen affects grapevine growth and also yeast metabolism, which have a direct influence on fermentation kinetics and the formation of different volatile compounds. Throughout the grapevine cycle, soil nitrogen availability and grape nitrogen composition can vary because of different factors. Nitrogen foliar applications can contribute toward enhancing grapevine nitrogen status and minimize the problem of leaching that traditional nitrogen-soil applications can provoke. The present study aimed to evaluate the influence of urea foliar applications on grapevine nitrogen status and grape amino acid content. Accordingly, two different doses of urea were applied over the leaves of a 'Tempranillo' vineyard. The highest urea doses affected nitrogen content on blade leaf tissues after veraison. Must amino acid profiles were modified by urea application and some of the compounds increased their concentrations. The effect of year on the increase of must total amino acid concentrations was more important than the effect of the doses applied. Urea foliar applications can be an interesting tool for decreasing grapevine nitrogen deficiencies. This method of nitrogen implementation in the vineyard could avoid sluggish fermentation problems during winemaking, enhance must nitrogen composition, and contribute to improving wine quality. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

  4. Sources, fate, and transport of nitrogen and phosphorus in the Chesapeake Bay watershed-An empirical model

    USGS Publications Warehouse

    Ator, Scott W.; Brakebill, John W.; Blomquist, Joel D.

    2011-01-01

    Nutrient fate and transport through the Chesapeake Bay watershed to the bay reflect the diferent physical and chemical properties of nitrogen and phosphorus compounds. Groundwater is an important pathway for nitrogen transport (as nitrate), and TN flux is greatest in areas with greater groundwater flow and in areas of the Piedmont underlain by carbonate rocks. TN flux decreases with increasing vegetative growth (likely indicative of plant uptake) and soil available water capacity (likely indicative of reducing conditions). Phosphorus transport to streams, conversely, is greatest in areas most likely to generate overland runoff and related erosion, including those with less permeable and more erodible soils and greater precipitation. Phosphorus transport also is greater in the Coastal Plain than in other areas, possibly due to saturation of soils with historical phosphorus applications. Both nitrogen and phosphorus are lost within watershed impoundments (lakes, ponds, or reservoirs), and nitrogen is also lost significantly along flowing reaches, particularly in small streams and in larger streams in warmer areas.

  5. Powder containing 2H-type silicon carbide produced by reacting silicon dioxide and carbon powder in nitrogen atmosphere in the presence of aluminum

    NASA Technical Reports Server (NTRS)

    Kuramoto, N.; Takiguchi, H.

    1984-01-01

    The production of powder which contains silicon carbide consisting of 40% of 2H-type silicon carbide, beta type silicon carbide and less than 3% of nitrogen is discussed. The reaction temperature to produce the powder containing 40% of 2H-type silicon carbide is set at above 1550 degrees C in an atmosphere of aluminum or aluminum compounds and nitrogen gas or an antioxidation atmosphere containing nitrogen gas. The mixture ratio of silicon dioxide and carbon powder is 0.55 - 1:2.0 and the contents of aluminum or aluminum compounds within silicon dioxide is less than 3% in weight.

  6. Flame resistant elastomeric polymer development. [for use in space shuttle instrument packaging

    NASA Technical Reports Server (NTRS)

    Howarth, J. T.; Sheth, S. G.; Sidman, K. R.

    1975-01-01

    Elastomeric products were developed for use in the space shuttle program, and investigations were conducted to improve the properties of elastomers developed in previous programs, and to evaluate the possibility of using lower-cost general purpose polymers. Products were fabricated and processed on conventional processing equipment; these products include: foams based on fluorinated rubber flame-retarded compounds with a density of 20-30 pounds/cubic foot for use as padding and in helmets; foams based on urethane for use in instrument packaging in the space shuttle; flexible and semi-rigid films of fluorinated rubber and neoprene compounds that would not burn in a 70% nitrogen, 30% oxygen atmosphere, and in a 30% nitrogen, 70% oxygen atmosphere, respectively for use in packaging or in laminates; coated fabrics which used both nylon and Kelvar fabric substrates, coated with either fluorinated or neoprene polymer compositions to meet specific levels of flame retardancy; and other flame-resistant materials.

  7. Azaquinolone dye lasers

    DOEpatents

    Hammond, Peter R.; Atkins, Ronald L.; Henry, Ronald A.; Fletcher, Aaron N.

    1978-01-01

    A dye laser comprising a laser dye solution of a compound having the general structure: ##STR1## wherein at least one of the 5, 6 and 8 ring positions is occupied by a nitrogen atom in lieu of the corresponding CR group and X is OH, alkoxy, or amino including amino substituted by at least one of the following: alkyl, aryl, acyl, aracyl, a group which taken together with the nitrogen atom of the amino group forms a heterocyclic ring, or part of one or two 5 or 6 membered aliphatic heterocyclic rings attached to ring A at positions 6 or 8 or both depending on where the N in ring A is located. R.sub.1, R.sub.3, R.sub.4, R.sub.5, R.sub.6 and R.sub.8 are hydrogen or other groups as defined below. The compounds lase in the blue to near ultraviolet region.

  8. Azacoumarin dye lasers

    DOEpatents

    Hammond, Peter R.; Atkins, Ronald L.; Henry, Ronald A.; Fletcher, Aaron N.

    1978-01-01

    A dye laser comprising a laser dye solution of a compound having the general structure: ##STR1## wherein at least one of the 5, 6 and 8 ring positions is occupied by a nitrogen atom in lieu of the corresponding CR group and X is OH, alkoxy, or amino including amino substituted by at least one of the following: alkyl, aryl, acyl, aracyl, a group which taken together with the nitrogen atom of the amino group forms a heterocyclic ring, or part of one or two 5 or 6 membered aliphatic heterocyclic rings attached to ring A at positions 6 or 8 or both depending on where the N in ring A is located. R.sub.3, R.sub.4, R.sub.5, R.sub.6 and R.sub.8 are hydrogen or other groups as defined below. The compounds lase in the blue-green to near ultraviolet region.

  9. Nitrogen-Containing Constituents of Black Cohosh: Chemistry, Structure Elucidation, and Biological Activities

    PubMed Central

    Lankin, David C.; Cisowska, Tamara; Chen, Shao-Nong; Pauli, Guido F.; van Breemen, Richard B.

    2016-01-01

    The roots/rhizomes of black cohosh (Actaea racemosa L. syn. Cimicifuga racemosa [L]. Nutt., Ranunculaceae) have been used traditionally by Native Americans to treat colds, rheumatism, and a variety of conditions related to women’s health. In recent years black cohosh preparations have become popular dietary supplements among women seeking alternative treatments for menopausal complaints. The popularity of the plant has led to extensive phytochemical and biological investigations, including several clinical trials. Most of the phytochemical and biological research has focused on two abundant classes of compounds: the triterpene glycosides and phenolic acids. A third group of phytoconstituents that has received far less attention consists of the alkaloids and related compounds that contain nitrogen. This chapter summarizes the current state of knowledge of the chemistry and biological activities associated with this group of constituents and provides some perspective on their significance for future research on this interesting plant. PMID:27795590

  10. Recent changes in anthropogenic reactive nitrogen compounds

    NASA Astrophysics Data System (ADS)

    Andronache, Constantin

    2014-05-01

    Significant anthropogenic perturbations of the nitrogen cycle are the result of rapid population growth, with mounting need for food and energy production. The increase of reactive nitrogen compounds (such as NOx, HNO3, NH3, and N2O) has a significant impact on human health, environment, and climate. NOx emissions contribute to O3 chemistry, aerosol formation and acidic precipitation. Ammonia is a notable atmospheric pollutant that may deteriorate ecosystems and contribute to respiratory problems. It reacts with acidic gases to form aerosols or is deposited back to ecosystems. The application of fertilizers accounts for most of the N2O production, adding to greenhouse gas emissions. We analyze the change of some reactive nitrogen compounds based on observations, in eastern United States. Results show that the control of NOx and SO2 emissions over the last decades caused a significant decrease of acidic deposition. The nitrate deposition is highest in eastern US, while the ammonium ion concentration is highest in central US regions. Overall, the inorganic nitrogen wet deposition from nitrate and ammonium is enhanced in central, and eastern US. Research shows that sensitive ecosystems in northeastern regions exhibit a slow recovery from the accumulated effects of acidic deposition. Given the growing demand for nitrogen in agriculture and industry, we discuss possible pathways to reduce the impact of excess reactive nitrogen on the environment.

  11. [Contents of nutrient elements in NH4(+)-N fertilizer and urea].

    PubMed

    Wang, Zheng-Rui; Qu, Gui-Qin; Rui, Yu-Kui; Shen, Jian-Bo; Zhang, Fu-Suo

    2009-03-01

    Fertilizer contains not only one compound or one element, so it is important to determine the contents of other elements necessitous and beneficial to plant. All the other nutrient elements for plant, including necessitous elements and beneficial elements in ammonia nitrogen fertilizer ((NH4)2SO4) and CO(NH2)2, were analyzed by method of ICP-MS. The results showed that ammonia nitrogen fertilizer ((NH4)2SO4) and CO(NH2)2 both contain many necessitous elements, Mg, P, K, Ca, Mn, Fe, Ni, Cu, Zn and Mo, thereinto the contents of Mg, P, K, Ca, Mn and Fe were on microg x g(-1) the level, and Ni, Cu, Zn and Mo were on the ng x g(-1) level; compared with CO(NH2)2, ammonia nitrogen fertilizer ((NH4)2SO4) contains more necessitous elements and beneficial elements except Mo and Si. All the above elements could influence the results of nitrogen fertilizer efficiency experiments, so pure fertilizer should be used in the future nitrogen fertilizer efficiency experiments and the comparative experiments of different form nitrogen fertilizer.

  12. 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...

  13. OPPORTUNITIES IN NITROGEN MANAGEMENT RESEARCH; IMPROVING APPLICATIONS FOR PROVEN TECHNOLOGIES AND IDENTIFYING NEW TOOLS FOR MANAGING NITROGEN FLUX AND INPUT IN ECOSYSTEMS

    EPA Science Inventory

    The presence and distribution of undesirable quantities of bioavailable nitrogenous compounds in the environment are issues of long-standing concern. Importantly for us today, deleterious effects associated with high levels of nitrogen in the ecosystem are becoming everyday news...

  14. INORGANIC COORDINATION POLYMERS. IV. THE ATTEMPTED REPLACEMENT OF ACETYLACETONATE LIGANDS WITH PICOLINATE LIGANDS,

    DTIC Science & Technology

    HETEROCYCLIC COMPOUNDS, PHOSPHENE OXIDES, BENZENE, CHROMIUM COMPOUNDS, CHEMICAL REAC, SYNTHESIS (CHEMISTRY), CHEMICAL ANALY, SPECTRA (INFRARED), ABSORPTION, DISPLACE, POLYMERIZATION, ORGANIC NITROGEN, AROMATIC COMPOUNDS.

  15. Study of the evolution of nitrogen compounds during grape ripening. application to differentiate grape varieties and cultivated systems.

    PubMed

    Garde-Cerdán, Teresa; Lorenzo, Cándida; Lara, José Félix; Pardo, Francisco; Ancín-Azpilicueta, Carmen; Salinas, M Rosario

    2009-03-25

    The aim of this work was to study the evolution of amino acids and ammonium during grape ripening and to evaluate its application to differentiate grape varieties and cultivated systems (organic and nonorganic). For this purpose, Monastrell, Syrah, Merlot, and Petit Verdot grapes produced using conventional agriculture and Monastrell grape cultivated using organic agriculture, collected during two consecutive harvests at different stages of ripening, were studied. These years of harvest were very different climatic years; even so, the grape varieties presented similar qualitative compositions. Therefore, the percentage of amino acids at harvest moment allowed differentiation of grapes according to variety and cultivated system, regardless of the year. The nitrogen composition could allow estimation of the fermentative aroma potential of grapes. Thus, Syrah was the grape with the greatest aroma potential at harvest. Monastrell nonorganic grape had a concentration of nitrogen compounds superior to that of Monastrell organic grape. In Monastrell, Syrah, and Merlot, traditional varieties in the area, the highest concentration of nitrogen compounds coincided with the highest degrees Baume/total acidity ratio and color index during 2007. Consequently, technological and phenolic maturity of these grape varieties coincided with the maximum composition of nitrogen compounds. However, in 2008, this did not happen because grape ripening was irregular as a consequence of different climatological conditions.

  16. Research on the degradation mechanism of pyridine in drinking water by dielectric barrier discharge.

    PubMed

    Li, Yang; Yi, Rongjie; Yi, Chengwu; Zhou, Biyun; Wang, Huijuan

    2017-03-01

    Pyridine, an important chemical raw material, is widely used in industry, for example in textiles, leather, printing, dyeing, etc. In this research, a dielectric barrier discharge (DBD) system was developed to remove pyridine, as a representative type of nitrogen heterocyclic compound in drinking water. First, the influence of the active species inhibitors tertiary butanol alcohol (TBA), HCO 3 - , and CO 3 2- on the degradation rate of pyridine was investigated to verify the existence of active species produced by the strong ionization discharge in the system. The intermediate and final products generated in the degradation process of pyridine were confirmed and analyzed through a series of analytical techniques, including liquid chromatography-mass spectrometry (LC-MS), high performance liquid chromatography (HPLC), ion chromatography (IC), total organic carbon (TOC) analysis, ultraviolet (UV) spectroscopy, etc. The results showed that the degradation of pyridine was mainly due to the strong oxidizing power of ozone and hydroxyl radical produced by the DBD system. Several intermediate products including 3-hydroxyl pyridine, fumaric acid, 2, 3-dihydroxypyridine, and oxalic acid were detected. Nitrogen was removed from the pyridine molecule to form nitrate. Through analysis of the degradation mechanism of pyridine, the oxidation pathway was deduced. The study provided a theoretical and experimental basis for the application of DBD strong ionization discharge in treatment of nitrogen heterocyclic compounds in drinking water. Copyright © 2016. Published by Elsevier B.V.

  17. Cattle feedlot soil moisture and manure content: I. Impacts on greenhouse gases, odor compounds, nitrogen losses, and dust.

    PubMed

    Miller, Daniel N; Berry, Elaine D

    2005-01-01

    Beef cattle feedlots face serious environmental challenges associated with manure management, including greenhouse gas, odor, NH3, and dust emissions. Conditions affecting emissions are poorly characterized, but likely relate to the variability of feedlot surface moisture and manure contents, which affect microbial processes. Odor compounds, greenhouse gases, nitrogen losses, and dust potential were monitored at six moisture contents (0.11, 0.25, 0.43, 0.67, 1.00, and 1.50 g H2O g(-1) dry matter [DM]) in three artificial feedlot soil mixtures containing 50, 250, and 750 g manure kg(-1) total (manure + soil) DM over a two-week period. Moisture addition produced three microbial metabolisms: inactive, aerobic, and fermentative at low, moderate, and high moisture, respectively. Manure content acted to modulate the effect of moisture and enhanced some microbial processes. Greenhouse gas (CO2, N2O, and CH4) emissions were dynamic at moderate to high moisture. Malodorous volatile fatty acid (VFA) compounds did not accumulate in any treatments, but their persistence and volatility varied depending on pH and aerobic metabolism. Starch was the dominant substrate fueling both aerobic and fermentative metabolism. Nitrogen losses were observed in all metabolically active treatments; however, there was evidence for limited microbial nitrogen uptake. Finally, potential dust production was observed below defined moisture thresholds, which were related to manure content of the soil. Managing feedlot surface moisture within a narrow moisture range (0.2-0.4 g H2O g(-1) DM) and minimizing the accumulation of manure produced the optimum conditions that minimized the environmental impact from cattle feedlot production.

  18. NITROGEN DIOXIDE, PULMONARY FUNCTION, AND RESPIRATORY DISEASE

    EPA Science Inventory

    Concern as to the toxicity of the oxides of nitrogen has been frequently expressed in clinical and toxicological literature. Oxides of nitrogen are highly reactive compounds and suggest toxic effects on biological systems. The earliest evidence for potential damage to man occurre...

  19. 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.

  20. Mechanisms of nitrogen heterocycle influence on turbine fuel stability

    NASA Technical Reports Server (NTRS)

    Daniel, S. R.; Worstell, J. H.

    1980-01-01

    Lewis bases were extracted from a Utah COED syncrude via ligand exchange. Addition of this extract to Jet A at levels as low as 5 ppm N produced deterioration of stability in both JFTOT and accelerated storage tests (7 days at 394 K with 13:1air to fuel ratio). Comparable effects on Jet A stability were obtained by addition of pyridine and quinoline, while pyrrole and indole were less detrimental at the same concentration level. The weight of deposit produced accelerated storage tests was found to be proportional to the concentration of added nitrogen compound. Over the narrow temperature range accessible with the experimental method, Arrhenius plots obtained by assuming specific rate to be proportional to the weight of material deposited in seven days exhibit greater slopes in the presence of those nitrogen compounds producing the greater deposition rates. It is shown that despite variation in appearance the elemental composition and spectral characteristics of the deposits are unaffected by addition of the nitrogen compounds. The linearity of the Arrhenius plots and of a plot of Arrhenius slope versus intercept for all the compounds suggests a constancy of mechanism over the range of temperature and heterocycles studied.

  1. Non-Saccharomyces Yeasts Nitrogen Source Preferences: Impact on Sequential Fermentation and Wine Volatile Compounds Profile

    PubMed Central

    Gobert, Antoine; Tourdot-Maréchal, Raphaëlle; Morge, Christophe; Sparrow, Céline; Liu, Youzhong; Quintanilla-Casas, Beatriz; Vichi, Stefania; Alexandre, Hervé

    2017-01-01

    Nitrogen sources in the must are important for yeast metabolism, growth, and performance, and wine volatile compounds profile. Yeast assimilable nitrogen (YAN) deficiencies in grape must are one of the main causes of stuck and sluggish fermentation. The nitrogen requirement of Saccharomyces cerevisiae metabolism has been described in detail. However, the YAN preferences of non-Saccharomyces yeasts remain unknown despite their increasingly widespread use in winemaking. Furthermore, the impact of nitrogen consumption by non-Saccharomyces yeasts on YAN availability, alcoholic performance and volatile compounds production by S. cerevisiae in sequential fermentation has been little studied. With a view to improving the use of non-Saccharomyces yeasts in winemaking, we studied the use of amino acids and ammonium by three strains of non-Saccharomyces yeasts (Starmerella bacillaris, Metschnikowia pulcherrima, and Pichia membranifaciens) in grape juice. We first determined which nitrogen sources were preferentially used by these yeasts in pure cultures at 28 and 20°C (because few data are available). We then carried out sequential fermentations at 20°C with S. cerevisiae, to assess the impact of the non-Saccharomyces yeasts on the availability of assimilable nitrogen for S. cerevisiae. Finally, 22 volatile compounds were quantified in sequential fermentation and their levels compared with those in pure cultures of S. cerevisiae. We report here, for the first time, that non-Saccharomyces yeasts have specific amino-acid consumption profiles. Histidine, methionine, threonine, and tyrosine were not consumed by S. bacillaris, aspartic acid was assimilated very slowly by M. pulcherrima, and glutamine was not assimilated by P. membranifaciens. By contrast, cysteine appeared to be a preferred nitrogen source for all non-Saccharomyces yeasts. In sequential fermentation, these specific profiles of amino-acid consumption by non-Saccharomyces yeasts may account for some of the interactions observed here, such as poorer performances of S. cerevisiae and volatile profile changes. PMID:29163451

  2. Non-Saccharomyces Yeasts Nitrogen Source Preferences: Impact on Sequential Fermentation and Wine Volatile Compounds Profile.

    PubMed

    Gobert, Antoine; Tourdot-Maréchal, Raphaëlle; Morge, Christophe; Sparrow, Céline; Liu, Youzhong; Quintanilla-Casas, Beatriz; Vichi, Stefania; Alexandre, Hervé

    2017-01-01

    Nitrogen sources in the must are important for yeast metabolism, growth, and performance, and wine volatile compounds profile. Yeast assimilable nitrogen (YAN) deficiencies in grape must are one of the main causes of stuck and sluggish fermentation. The nitrogen requirement of Saccharomyces cerevisiae metabolism has been described in detail. However, the YAN preferences of non- Saccharomyces yeasts remain unknown despite their increasingly widespread use in winemaking. Furthermore, the impact of nitrogen consumption by non- Saccharomyces yeasts on YAN availability, alcoholic performance and volatile compounds production by S. cerevisiae in sequential fermentation has been little studied. With a view to improving the use of non- Saccharomyces yeasts in winemaking, we studied the use of amino acids and ammonium by three strains of non- Saccharomyces yeasts ( Starmerella bacillaris, Metschnikowia pulcherrima , and Pichia membranifaciens ) in grape juice. We first determined which nitrogen sources were preferentially used by these yeasts in pure cultures at 28 and 20°C (because few data are available). We then carried out sequential fermentations at 20°C with S. cerevisiae , to assess the impact of the non- Saccharomyces yeasts on the availability of assimilable nitrogen for S. cerevisiae . Finally, 22 volatile compounds were quantified in sequential fermentation and their levels compared with those in pure cultures of S. cerevisiae . We report here, for the first time, that non- Saccharomyces yeasts have specific amino-acid consumption profiles. Histidine, methionine, threonine, and tyrosine were not consumed by S. bacillaris , aspartic acid was assimilated very slowly by M. pulcherrima , and glutamine was not assimilated by P. membranifaciens . By contrast, cysteine appeared to be a preferred nitrogen source for all non- Saccharomyces yeasts. In sequential fermentation, these specific profiles of amino-acid consumption by non- Saccharomyces yeasts may account for some of the interactions observed here, such as poorer performances of S. cerevisiae and volatile profile changes.

  3. A novel bisphosphonate inhibitor of squalene synthase combined with a statin or a nitrogenous bisphosphonate in vitro[S

    PubMed Central

    Wasko, Brian M.; Smits, Jacqueline P.; Shull, Larry W.; Wiemer, David F.; Hohl, Raymond J.

    2011-01-01

    Statins and nitrogenous bisphosphonates (NBP) inhibit 3-hydroxy-3-methylglutaryl-coenzyme-A reductase (HMGCR) and farnesyl diphosphate synthase (FDPS), respectively, leading to depletion of farnesyl diphosphate (FPP) and disruption of protein prenylation. Squalene synthase (SQS) utilizes FPP in the first committed step from the mevalonate pathway toward cholesterol biosynthesis. Herein, we have identified novel bisphosphonates as potent and specific inhibitors of SQS, including the tetrasodium salt of 9-biphenyl-4,8-dimethyl-nona-3,7-dienyl-1,1-bisphosphonic acid (compound 5). Compound 5 reduced cholesterol biosynthesis and lead to a substantial intracellular accumulation of FPP without reducing cell viability in HepG2 cells. At high concentrations, lovastatin and zoledronate impaired protein prenylation and decreased cell viability, which limits their potential use for cholesterol depletion. When combined with lovastatin, compound 5 prevented lovastatin-induced FPP depletion and impairment of protein farnesylation. Compound 5 in combination with the NBP zoledronate completely prevented zoledronate-induced impairment of both protein farnesylation and geranylgeranylation. Cotreatment of cells with compound 5 and either lovastatin or zoledronate was able to significantly prevent the reduction of cell viability caused by lovastatin or zoledronate alone. The combination of an SQS inhibitor with an HMGCR or FDPS inhibitor provides a rational approach for reducing cholesterol synthesis while preventing nonsterol isoprenoid depletion. PMID:21903868

  4. The adjuvant activity of aliphatic nitrogenous bases

    PubMed Central

    Gall, D.

    1966-01-01

    By the use of diphtheria toxoid in guinea-pigs, high adjuvant activity has been found in a number of aliphatic nitrogenous bases including amines, quaternary ammonium compounds, guanidines, benzamidines and thiouroniums. Activity appears to depend on a combination of basicity and a long aliphatic chain of twelve or more carbon atoms. Such adjuvants tend to be haemolytic, and cause damage to tissue culture monolayers. It is suggested that their activity is connected with their surface activity and hence their ability to alter cell membranes, but that the basicity plays a further as yet undetermined role. ImagesFIG. 1-2FIG. 3-4 PMID:5924622

  5. Quantitative Estimation of the Electronic Effects of Substituents in Five-membered Nitrogen-containing Aromatic Heterocycles

    NASA Astrophysics Data System (ADS)

    Lopyrev, Valentin A.; Larina, Ludmila I.; Vakul'skaya, Tamara I.

    1986-05-01

    Data, characterising quantitatively the effect of substituents on the reactivity and physicochemical properties of five-membered nitrogen-containing heterocyclic compounds, which have accumulated in the literature during the last 15 years, are compiled in the review and discussed. The possibility of applying the Hammett and Jaffe equations in the determination of the direction of transmission of the electronic effects of substituents is analysed and the likely usefulness of this approach to the study of electronic influences by taking into account separately the inductive and resonance constants is demonstrated. The bibliography includes 215 references.

  6. Organic Nitrogen in Atmospheric Drops and Particles: Concentrations, (Limited) Speciation, and Chemical Transformations

    NASA Astrophysics Data System (ADS)

    Anastasio, C.; Zhang, Q.

    2003-12-01

    While quite a bit is known of the concentrations, speciation, and chemistry of inorganic forms of nitrogen in the atmosphere, the same cannot be said for organic forms. Despite this, there is growing evidence that organic N (ON) is ubiquitous in the atmosphere, especially in atmospheric condensed phases such as fog/cloud drops and aerosol particles. Although the major compounds that make up organic N are generally unknown, as are the sources of these compounds, it is clear that there are significant fluxes of ON between the atmosphere and ecosystems. It also appears that organic N can have significant effects in both spheres. The goal of our recent work in this area has been to better describe the atmospheric component of the biogeochemistry of organic nitrogen. Based on particle, gas, and fogwater samples from Northern California we have made three major findings: 1) Organic N represents a significant component, approximately 20%, of the total atmospheric N loading in these samples. This is broadly consistent with studies from other locations. 2) Amino compounds, primarily as combined amino acids, account for approximately 20% of the measured ON in our condensed phase samples. Given the properties of amino acids, these compounds could significantly affect the chemical and physical properties of atmospheric particles. 3) Organic nitrogen in atmospheric particles and drops is transformed to inorganic forms - primarily ammonium, nitrate, and nitrogen oxides (NOx) - during exposure to sunlight and/or ozone. These chemical reactions likely increase the bioavailability of the condensed phase nitrogen pool and enhance its biological effects after deposition to ecosystems.

  7. Evolution of the composition of a selected bitter Camembert cheese during ripening: release and migration of taste-active compounds.

    PubMed

    Engel, E; Tournier, C; Salles, C; Le Quéré, J L

    2001-06-01

    The aim of this study was to add to the understanding of changes in taste that occur during the ripening of a bitter Camembert cheese by the evolution of its composition. Physicochemical analyses were performed on rind, under-rind, and center portions of a Camembert cheese selected for its intense bitterness. At each of the six steps of ripening studied organic acids, sugars, total nitrogen, soluble nitrogen, phosphotungstic acid soluble nitrogen, non-protein nitrogen, Na, K, Ca, Mg, Pi, Cl, and biogenic amines were quantified in each portion. Changes in cheese composition seemed to mainly result from the development of Penicillium camemberti on the cheese outer layer. Migration phenomena and the release of potentially taste-active compounds allowed for the evolution of saltiness, sourness, and bitterness throughout ripening to be better understood. Apart from taste-active compounds, the impact of the cheese matrix on its taste development is discussed.

  8. Facile scission of isonitrile carbon–nitrogen triple bond using a diborane(4) reagent

    PubMed Central

    Asakawa, Hiroki; Lee, Ka-Ho; Lin, Zhenyang; Yamashita, Makoto

    2014-01-01

    Transition metal reagents and catalysts are generally effective to cleave all three bonds (one σ and two π) in a triple bond despite its high bonding energy. Recently, chemistry of single-bond cleavage by using main-group element compounds is rapidly being developed in the absence of transition metals. However, the cleavage of a triple bond using non-transition-metal compounds is less explored. Here we report that an unsymmetrical diborane(4) compound could react with carbon monoxide and tert-butyl isonitrile at room temperature. In the latter case, the carbon–nitrogen triple bond was completely cleaved in the absence of transition metal as confirmed by X-ray crystallographic analysis, 13C NMR spectroscopy with 13C labelling and DFT calculations. The DFT calculations also revealed the detailed reaction mechanism and indicated that the key for the carbon–nitrogen triple-bond cleavage could be attributed to the presence of nucleophilic nitrogen atom in one of the intermediates. PMID:24967910

  9. A series of inorganic solid nitrogen sources for the synthesis of metal nitride clusterfullerenes: the dependence of production yield on the oxidation state of nitrogen and counter ion.

    PubMed

    Liu, Fupin; Guan, Jian; Wei, Tao; Wang, Song; Jiao, Mingzhi; Yang, Shangfeng

    2013-04-01

    A series of nitrogen-containing inorganic solid compounds with variable oxidation states of nitrogen and counter ions have been successfully applied as new inorganic solid nitrogen sources toward the synthesis of Sc-based metal nitride clusterfullerenes (Sc-NCFs), including ammonium salts [(NH4)xH(3-x)PO4 (x = 0-2), (NH4)2SO4, (NH4)2CO3, NH4X (X = F, Cl), NH4SCN], thiocyanate (KSCN), nitrates (Cu(NO3)2, NaNO3), and nitrite (NaNO2). Among them, ammonium phosphates ((NH4)xH(3-x)PO4, x = 1-3) and ammonium thiocyanate (NH4SCN) are revealed to behave as better nitrogen sources than others, and the highest yield of Sc-NCFs is achieved when NH4SCN was used as a nitrogen source. The optimum molar ratio of Sc2O3:(NH4)3PO4·3H2O:C and Sc2O3:NH4SCN:C has been determined to be 1:2:15 and 1:3:15, respectively. The thermal decomposition products of these 12 inorganic compounds have been discussed in order to understand their different performances toward the synthesis of Sc-NCFs, and accordingly the dependence of the production yield of Sc-NCFs on the oxidation state of nitrogen and counter ion is interpreted. The yield of Sc3N@C80 (I(h) + D(5h)) per gram Sc2O3 by using the N2-based group of nitrogen sources (thiocyanate, nitrates, and nitrite) is overall much lower than those by using gaseous N2 and NH4SCN, indicating the strong dependence of the yield of Sc-NCFs on the oxidation state of nitrogen, which is attributed to the "in-situ" redox reaction taking place for the N2-based group of nitrogen sources during discharging. For NH3-based group of nitrogen sources (ammonium salts) which exhibits a (-3) oxidation states of nitrogen, their performance as nitrogen sources is found to be sensitively dependent on the anion, and this is understood by considering their difference on the thermal stability and/or decomposition rate. Contrarily, for the N2-based group of nitrogen sources, the formation of Sc-NCFs is independent to both the oxidation state of nitrogen (+3 or +5) and the cation.

  10. Plants can use protein as a nitrogen source without assistance from other organisms

    PubMed Central

    Paungfoo-Lonhienne, Chanyarat; Lonhienne, Thierry G. A.; Rentsch, Doris; Robinson, Nicole; Christie, Michael; Webb, Richard I.; Gamage, Harshi K.; Carroll, Bernard J.; Schenk, Peer M.; Schmidt, Susanne

    2008-01-01

    Nitrogen is quantitatively the most important nutrient that plants acquire from the soil. It is well established that plant roots take up nitrogen compounds of low molecular mass, including ammonium, nitrate, and amino acids. However, in the soil of natural ecosystems, nitrogen occurs predominantly as proteins. This complex organic form of nitrogen is considered to be not directly available to plants. We examined the long-held view that plants depend on specialized symbioses with fungi (mycorrhizas) to access soil protein and studied the woody heathland plant Hakea actites and the herbaceous model plant Arabidopsis thaliana, which do not form mycorrhizas. We show that both species can use protein as a nitrogen source for growth without assistance from other organisms. We identified two mechanisms by which roots access protein. Roots exude proteolytic enzymes that digest protein at the root surface and possibly in the apoplast of the root cortex. Intact protein also was taken up into root cells most likely via endocytosis. These findings change our view of the spectrum of nitrogen sources that plants can access and challenge the current paradigm that plants rely on microbes and soil fauna for the breakdown of organic matter. PMID:18334638

  11. Sulfite Oxidase Activity Is Essential for Normal Sulfur, Nitrogen and Carbon Metabolism in Tomato Leaves

    PubMed Central

    Brychkova, Galina; Yarmolinsky, Dmitry; Batushansky, Albert; Grishkevich, Vladislav; Khozin-Goldberg, Inna; Fait, Aaron; Amir, Rachel; Fluhr, Robert; Sagi, Moshe

    2015-01-01

    Plant sulfite oxidase [SO; E.C.1.8.3.1] has been shown to be a key player in protecting plants against exogenous toxic sulfite. Recently we showed that SO activity is essential to cope with rising dark-induced endogenous sulfite levels in tomato plants (Lycopersicon esculentum/Solanum lycopersicum Mill. cv. Rheinlands Ruhm). Here we uncover the ramifications of SO impairment on carbon, nitrogen and sulfur (S) metabolites. Current analysis of the wild-type and SO-impaired plants revealed that under controlled conditions, the imbalanced sulfite level resulting from SO impairment conferred a metabolic shift towards elevated reduced S-compounds, namely sulfide, S-amino acids (S-AA), Co-A and acetyl-CoA, followed by non-S-AA, nitrogen and carbon metabolite enhancement, including polar lipids. Exposing plants to dark-induced carbon starvation resulted in a higher degradation of S-compounds, total AA, carbohydrates, polar lipids and total RNA in the mutant plants. Significantly, a failure to balance the carbon backbones was evident in the mutants, indicated by an increase in tricarboxylic acid cycle (TCA) cycle intermediates, whereas a decrease was shown in stressed wild-type plants. These results indicate that the role of SO is not limited to a rescue reaction under elevated sulfite, but SO is a key player in maintaining optimal carbon, nitrogen and sulfur metabolism in tomato plants. PMID:27135342

  12. Measurements of Positive Ambient Ions in Lamont OK as Part of the Holistic Interaction of Shallow Clouds Aerosols and Land Ecosystems (HISCALE II) Field Campaign

    NASA Astrophysics Data System (ADS)

    Abdelhamid, A.; Stark, H.; Worsnop, D. R.; Nowak, J. B.; Kuang, C.; Bullard, R.; Browne, E. C.

    2017-12-01

    Atmospheric ions control the electrical properties of the atmosphere, influence chemical composition via ion-molecule and/or ion-catalyzed reactions, and affect new particle formation. Understanding the role of ions in these processes requires knowledge of ionic chemical composition. Due to the low concentration of ions, chemical composition measurements have historically been challenging. Recent advances in mass spectrometry, such as the atmospheric pressure interface time-of-flight mass spectrometer (APi-TOF), are now making these measurements more feasible. Here, we present measurements of ambient cations during the HISCALE II field campaign (August- September 2016) in Lamont, OK. We discuss how the chemical composition of cations varies over the course of the campaign including before, during, and after new particle formation events. We specifically focus on the composition of organic nitrogen ions due to the potential importance of these compounds in atmospheric nucleation. We compare our results to measurements of neutral organic nitrogen compounds in order to gain insight into how organic nitrogen is chemically transformed in the atmosphere and how this influences new particle formation.

  13. Effects of salinity and nitrogen supply on the quality and health-related compounds of strawberry fruits (Fragaria × ananassa cv. Primoris).

    PubMed

    Cardeñosa, Vanessa; Medrano, Evangelina; Lorenzo, Pilar; Sánchez-Guerrero, Maria Cruz; Cuevas, Francisco; Pradas, Inmaculada; Moreno-Rojas, José M

    2015-11-01

    Different nitrogen inputs and/or development under adverse water conditions (water stress/low quality and/or high salinity/electrical conductivity), such as those prevailing in Almeria (Mediterranean coast, south-east Spain), may affect overall fruit and vegetable quality. This study evaluated the influence of salinity and nitrogen reduction in hydroponic nutrient solution on strawberry fruit quality and nutritional compounds (Fragaria × ananassa Duch., cv. Primoris). Strawberries obtained under salinity treatments recorded the highest values for soluble solids content (SSC; all samplings); fruit taste was thus enhanced. Additionally, salinity improved fruit nutritional value, with higher contents of antioxidants compounds (first sampling). During first and second samplings, strawberries grown under N reduction and non-saline conditions showed higher values for firmness compared to fruits developed under other treatments. Regarding health-related compounds, few differences were found except for total polyphenols concentration and antioxidant activity for the first sampling, where strawberries grown under saline treatments obtained the highest values for both parameters. The use of low-quality waters, such as those found in Almeria (salinity, N9S and N5S) and low nitrogen inputs (N5, avoid environmental impact) for strawberry cultivation does not exert a negative impact on overall quality. Positive differences could be found in SSC, firmness and health-related compounds when compared against the control treatment (N9). © 2014 Society of Chemical Industry.

  14. The comparison of phosphorus-nitrogen and sulfur-phosphorus-nitrogen on the anti-flammability and thermal degradation of cotton fabrics

    USDA-ARS?s Scientific Manuscript database

    The phosphorus-nitrogen (P-N) or sulfur (S) containing compounds are well known for their effectiveness as flame retardant additives for many polymeric systems. When either phosphorus or nitrogen is combined with sulfur, the new systems prove to be successful combinations. This research aims to le...

  15. Chemical Variability and Biological Activities of Brassica rapa var. rapifera Parts Essential Oils Depending on Geographic Variation and Extraction Technique.

    PubMed

    Saka, Boualem; Djouahri, Abderrahmane; Djerrad, Zineb; Terfi, Souhila; Aberrane, Sihem; Sabaou, Nasserdine; Baaliouamer, Aoumeur; Boudarene, Lynda

    2017-06-01

    In the present work, the Brassica rapa var. rapifera parts essential oils and their antioxidant and antimicrobial activities were investigated for the first time depending on geographic origin and extraction technique. Gas-chromatography (GC) and GC/mass spectrometry (MS) analyses showed several constituents, including alcohols, aldehydes, esters, ketones, norisoprenoids, terpenic, nitrogen and sulphur compounds, totalizing 38 and 41 compounds in leaves and root essential oils, respectively. Nitrogen compounds were the main volatiles in leaves essential oils and sulphur compounds were the main volatiles in root essential oils. Qualitative and quantitative differences were found among B. rapa var. rapifera parts essential oils collected from different locations and extracted by hydrodistillation and microwave-assisted hydrodistillation techniques. Furthermore, our findings showed a high variability for both antioxidant and antimicrobial activities. The highlighted variability reflects the high impact of plant part, geographic variation and extraction technique on chemical composition and biological activities, which led to conclude that we should select essential oils to be investigated carefully depending on these factors, in order to isolate the bioactive components or to have the best quality of essential oil in terms of biological activities and preventive effects in food. © 2017 Wiley-VHCA AG, Zurich, Switzerland.

  16. Comparative study on pyrolysis of lignocellulosic and algal biomass using pyrolysis-gas chromatography/mass spectrometry.

    PubMed

    Li, Kai; Zhang, Liqiang; Zhu, Liang; Zhu, Xifeng

    2017-06-01

    The cornstalk and chlorella were selected as the representative of lignocelulosic and algal biomass, and the pyrolysis experiments of them were carried out using pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS). The physicochemical properties of samples and the pyrolytic product distribution were presented. And then the compositional differences between the two kinds of pyrolytic products were studied, the relevant pyrolysis mechanisms were analyzed systematically. Pyrolytic vapor from lignocellulosic biomass contained more phenolic and carbonyl compounds while that from algal biomass contained more long-chain fatty acids, nitrogen-containing compounds and fewer carbonyl compounds. Maillard reaction is conducive to the conversion of carbonyl compounds to nitrogenous heterocyclic compounds with better thermal stability. Copyright © 2017 Elsevier Ltd. All rights reserved.

  17. NOx control techniques for the CPI

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Lambert, D.; McGowan, T.F.

    1996-06-01

    After years of air pollution control innovation, the control of emissions of nitrogen oxide compounds stands out as an area where much work remains to be performed in the chemical process industries (CPI). Federal regulations, ozone non-attainment areas, acid rain provisions of the US Clean Air Act, and corporate goals for emission reductions are all motivators. Primary CPI sources are high-temperature combustion systems, including fired heaters, boilers and Kilns. Nitrogen-based processes such as nitric acid manufacture also contribute. The paper discusses the regulations which define the problem and some solutions. These include fuel switching, low-excess air burners, fluegas recirculation, stagedmore » combustion, out of service burners, and wet scrubbing of flue gas. The paper briefly discusses costs of these options.« less

  18. Water quality in the eastern Iowa basins, Iowa and Minnesota, 1996-98

    USGS Publications Warehouse

    Kalkhoff, Stephen J.; Barnes, Kimberlee K.; Becher, Kent D.; Savoca, Mark E.; Schnoebelen, Douglas J.; Sadorf, Eric M.; Porter, Stephen D.; Sullivan, Daniel J.

    2000-01-01

    The water quality in rivers and streams and in selected aquifers in eastern Iowa and part of southern Minnesota is described and illustrated. Major ions, nitrogen and other nutrients, and pesticides and some of their breakdown compounds were analyzed in both surface and ground water. Biological communities that included fish, invertebrates, and algae, were described in relation to stream water quality. Volatile organic compounds that originate from fuels, solvent, and industry were analyzed from ground-water samples. Agricultural and urban land-use effects on shallow ground-water compared and contrasted.

  19. Discovery of Fungal Denitrification Inhibitors by Targeting Copper Nitrite Reductase from Fusarium oxysporum.

    PubMed

    Matsuoka, Masaki; Kumar, Ashutosh; Muddassar, Muhammad; Matsuyama, Akihisa; Yoshida, Minoru; Zhang, Kam Y J

    2017-02-27

    The efficient application of nitrogenous fertilizers is urgently required, as their excessive and inefficient use is causing substantial economic loss and environmental pollution. A significant amount of applied nitrogen in agricultural soils is lost as nitrous oxide (N 2 O) in the environment due to the microbial denitrification process. The widely distributed fungus Fusarium oxysporum is a major denitrifier in agricultural soils and its denitrification activity could be targeted to reduce nitrogen loss in the form of N 2 O from agricultural soils. Here, we report the discovery of first small molecule inhibitors of copper nitrite reductase (NirK) from F. oxysporum, which is a key enzyme in the fungal denitrification process. The inhibitors were discovered by a hierarchical in silico screening approach consisting of pharmacophore modeling and molecular docking. In vitro evaluation of F. oxysporum NirK activity revealed several pyrimidone and triazinone based compounds with potency in the low micromolar range. Some of these compounds suppressed the fungal denitrification in vivo as well. The compounds reported here could be used as starting points for the development of nitrogenous fertilizer supplements and coatings as a means to prevent nitrogen loss by targeting fungal denitrification.

  20. Effects of nitrogen fertilization on the phenolic composition and antioxidant properties of basil (Ocimum basilicum L.).

    PubMed

    Nguyen, Phuong M; Niemeyer, Emily D

    2008-09-24

    Many herbs and spices have been shown to contain high levels of polyphenolic compounds with potent antioxidant properties. In the present study, we explore how nutrient availability, specifically nitrogen fertilization, affects the production of polyphenolic compounds in three cultivars (Dark Opal, Genovese, and Sweet Thai) of the culinary herb, basil ( Ocimum basilicum L.). Nitrogen fertilization was found to have a significant effect on total phenolic levels in Dark Opal ( p < 0.001) and Genovese ( p < 0.001) basil with statistically higher phenolic contents observed when nutrient availability was limited at the lowest (0.1 mM) applied nitrogen treatment. Similarly, basil treated at the lowest nitrogen fertilization level generally contained significantly higher rosmarinic ( p = 0.001) and caffeic ( p = 0.001) acid concentrations than basil treated at other nitrogen levels. Nitrogen fertilization also affected antioxidant activity ( p = 0.002) with basil treated at the highest applied nitrogen level, 5.0 mM, exhibiting lower antioxidant activity than all other nitrogen treatments. The anthocyanin content of Dark Opal basil was not affected by applied nitrogen level, but anthocyanin concentrations were significantly impacted by growing season ( p = 0.001). Basil cultivar was also determined to have a statistically significant effect on total phenolic levels, rosmarinic and caffeic acid concentrations, and antioxidant activities.

  1. Food preferences of mangrove crabs related to leaf nitrogen compounds in the Segara Anakan Lagoon, Java, Indonesia

    NASA Astrophysics Data System (ADS)

    Nordhaus, Inga; Salewski, Tabea; Jennerjahn, Tim C.

    2011-05-01

    The large amounts of leaf litter produced by tropical mangrove forests serve as a major food source for the benthic fauna. The reasons for the preferential consumption of mangrove leaves by crabs are unclear as yet. We investigated the diet, food preferences and consumption rates of 8 dominant grapsoid crab species ( Perisesarma spp., Episesarma spp., Metopograpsus latifrons, and Metaplax elegans) in mangroves of Segara Anakan, Java, Indonesia, by means of stomach-content analysis and feeding experiments. Leaves from the five most abundant mangrove tree species ( Aegiceras corniculatum, Avicennia alba, Ceriops decandra, Rhizophora apiculata, and Sonneratia caseolaris) were analyzed for organic carbon, total nitrogen, δ 13C, δ 15N and amino acids and hexosamines. This study is the first that investigated crab food preferences related to the nitrogen compound composition of leaves. Our results show that Episesarma spp. and Perisesarma spp. are omnivorous crabs which mainly feed on detritus, mangrove litter and bark, and on a small amount of roots, algae and animal matter whereas M. elegans is a detritus feeder. In feeding experiments with green, yellow and brown leaves Perisesarma spp. and E. singaporense had the highest consumption rates for brown leaves of R. apiculata and S. caseolaris, and for green leaves of A. alba. Preferred leaves were characterized by a high amount and/or freshness of nitrogenous compounds and their biochemical composition was significantly different from that of disliked leaves (all leaves of A. corniculatum and C. decandra, green and yellow leaves of R. apiculata and S. caseolaris). The presence of the hexosamine galactosamine found only in brown leaves indicates that bacteria contribute to the amount of bioavailable nitrogen compounds. We infer that the nitrogen compound composition rather than the C/N ratio alone is a determinant for bioavailability of mangrove leaves and hence may partly explain the crabs' food preferences.

  2. 4-Aminoquinolines Active against Chloroquine-Resistant Plasmodium falciparum: Basis of Antiparasite Activity and Quantitative Structure-Activity Relationship Analyses▿

    PubMed Central

    Hocart, Simon J.; Liu, Huayin; Deng, Haiyan; De, Dibyendu; Krogstad, Frances M.; Krogstad, Donald J.

    2011-01-01

    Chloroquine (CQ) is a safe and economical 4-aminoquinoline (AQ) antimalarial. However, its value has been severely compromised by the increasing prevalence of CQ resistance. This study examined 108 AQs, including 68 newly synthesized compounds. Of these 108 AQs, 32 (30%) were active only against CQ-susceptible Plasmodium falciparum strains and 59 (55%) were active against both CQ-susceptible and CQ-resistant P. falciparum strains (50% inhibitory concentrations [IC50s], ≤25 nM). All AQs active against both CQ-susceptible and CQ-resistant P. falciparum strains shared four structural features: (i) an AQ ring without alkyl substitution, (ii) a halogen at position 7 (Cl, Br, or I but not F), (iii) a protonatable nitrogen at position 1, and (iv) a second protonatable nitrogen at the end of the side chain distal from the point of attachment to the AQ ring via the nitrogen at position 4. For activity against CQ-resistant parasites, side chain lengths of ≤3 or ≥10 carbons were necessary but not sufficient; they were identified as essential factors by visual comparison of 2-dimensional (2-D) structures in relation to the antiparasite activities of the AQs and were confirmed by computer-based 3-D comparisons and differential contour plots of activity against P. falciparum. The advantage of the method reported here (refinement of quantitative structure-activity relationship [QSAR] descriptors by random assignment of compounds to multiple training and test sets) is that it retains QSAR descriptors according to their abilities to predict the activities of unknown test compounds rather than according to how well they fit the activities of the compounds in the training sets. PMID:21383099

  3. Influence of temperature on nitrogen fate during hydrothermal carbonization of food waste.

    PubMed

    Wang, Tengfei; Zhai, Yunbo; Zhu, Yun; Peng, Chuan; Xu, Bibo; Wang, Tao; Li, Caiting; Zeng, Guangming

    2018-01-01

    The influence of temperature (180-260°C) on the fate of nitrogen during hydrothermal carbonization (HTC) of food waste (FW) was assessed. The distribution and evolution of nitrogen in aqueous products and bio-oil, as well as hydrochar, were conducted. Results suggested that elevated temperature enhanced the deamination and the highest ammonium concentration (929.75mg/L) was acquired at 260°C. At temperatures above 220°C, the total N in the hydrochar became stable, whereas the mass percentage of N increased. Amines and heterocyclic-N compounds from protein cracking and Maillard reactions were identified as the main nitrogen-containing compounds in the bio-oil. As to the hydrochar, increasing temperature resulted in condensed nitrogen-containing aromatic heterocycles (e.g. pyridine-N and quaternary-N). In particular, remarkable Maillard reactions at 180°C and the highest temperature at 260°C enhanced nitrogen incorporation (i.e. quaternary-N) into hydrochar. Copyright © 2017 Elsevier Ltd. All rights reserved.

  4. Relationships between chemical structure and rat repellency. II. Compounds screened between 1950 and 1960

    USGS Publications Warehouse

    Bowles, W.A.; Adomaitis, V.A.; DeWitt, J.B.; Pratt, J.J.

    1974-01-01

    Over 4,600 compounds, chiefly organic types, were evaluated using both a food acceptance test (Part A) and a barrier penetration bioassay (Part B), to correlate relationships between chemical structure and rodent repellency.These chemicals are indexed and classified according to the functional groups present and to the degree of substitution within their molecular structures. The results of reduction in foot consumption for each compound appraised are calculated and their K values listed in Table I.The repellent activities of the functional groups represented, alone or in combinations, are expressed in Table II by a Functional Group Repellency Index. A ranking of these indices suggests that acyclic and heteroyclic compounds containing tri- or pentavalent nitrogen would be a parent compound of choice for synthesizing novel repellents. Other molecular arrangements, spatial configurations and combinations of functional groups are compared.There were 123 active, interesting or promising compounds included in the 699 having K values of 85 or greater, which were selected for the barrier appraisal study. These chemicals were formulated in selective solvents at several concentrations and applied to burlap. Small foot bags were fashioned using the fabric impregnated with the candidate formulation, and exposed to rodent attack following storage periods of varying intervals. The results of these tests are listed in Table III. Again, those compounds containing nitrogen in the functional groupings indicated a high order of effectiveness. Several commercial patents covering rodent repellents were issued using the data from the food acceptance and barrier studies.Organizations and cooperators which supplied samples for the program are listed in Appendix I. The Wiswesser cipher for compounds in Table I is used in Appendix II to facilitate location of chemicals by sample code number as they appear under the index headings, and for computer storage and analysis.

  5. Relationships between chemical structure and rat repellency: II. compounds screened between 1950 and 1960

    USGS Publications Warehouse

    Bowles, Walter A.; Adomaitis, V.A.; DeWitt, J.B.; Pratt, J.J.

    1974-01-01

    Over 4,600 compounds, chiefly organic types, were evaluated using both a food acceptance test (Part A) and a barrier penetration bioassay (Part B), to correlate relationships between chemical structure and rodent repellency. These chemicals are indexed and classified according to the functional groups present and to the degree of substitution within their molecular structures. The results of reduction in food consumption for each compound appraised are calculated and their K values listed in Table 1. The repellent activities of the functional groups represented, alone or in combinations, are expressed in Table II by a Functional Group Repellency Index.. A ranking of these indices suggests that acyclic and heteroyclic compounds containing tri- or pentavalent nitrogen would be a parent compound of choice for synthesizing novel repellents. Other molecular arrangements, spatial configurations and combinations of functional groups are compared. There were 123 active, interesting or promising compounds included in the 699 having K values of 85 or greater, which were selected for the barrier appraisal study. These chemicals were formulated in selective solvents at several concentrations and applied to burlap. Small food bags were fashioned using the fabric impregnated with the candidate formulation, and exposed to rodent attack following storage periods of varying intervals. The results of these tests are listed in Table III. Again, those compounds containing nitrogen in the functional groupings indicated a high order of effectiveness. Several commercial patents covering rodent repellents were issued using the data from the food acceptance and barrier studies. Organizations and cooperators which supplied samples for the program are listed in Appendix I. The Wiswesser cipher for compounds in Table I is used in Appendix II to facilitate location of chemicals by sample code number as they appear under the index headings, and for computer storage and analysis.

  6. Multi-omics analysis reveals regulators of the response to nitrogen limitation in Yarrowia lipolytica.

    PubMed

    Pomraning, Kyle R; Kim, Young-Mo; Nicora, Carrie D; Chu, Rosalie K; Bredeweg, Erin L; Purvine, Samuel O; Hu, Dehong; Metz, Thomas O; Baker, Scott E

    2016-02-25

    Yarrowia lipolytica is an oleaginous ascomycete yeast that stores lipids in response to limitation of nitrogen. While the enzymatic pathways responsible for neutral lipid accumulation in Y. lipolytica are well characterized, regulation of these pathways has received little attention. We therefore sought to characterize the response to nitrogen limitation at system-wide levels, including the proteome, phosphoproteome and metabolome, to better understand how this organism regulates and controls lipid metabolism and to identify targets that may be manipulated to improve lipid yield. We found that ribosome structural genes are down-regulated under nitrogen limitation, during which nitrogen containing compounds (alanine, putrescine, spermidine and urea) are depleted and sugar alcohols and TCA cycle intermediates accumulate (citrate, fumarate and malate). We identified 1219 novel phosphorylation sites in Y. lipolytica, 133 of which change in their abundance during nitrogen limitation. Regulatory proteins, including kinases and DNA binding proteins, are particularly enriched for phosphorylation. Within lipid synthesis pathways, we found that ATP-citrate lyase, acetyl-CoA carboxylase and lecithin cholesterol acyl transferase are phosphorylated during nitrogen limitation while many of the proteins involved in β-oxidation are down-regulated, suggesting that storage lipid accumulation may be regulated by phosphorylation of key enzymes. Further, we identified short DNA elements that associate specific transcription factor families with up- and down-regulated genes. Integration of metabolome, proteome and phosphoproteome data identifies lipid accumulation in response to nitrogen limitation as a two-fold result of increased production of acetyl-CoA from excess citrate and decreased capacity for β-oxidation.

  7. Infrared Spectroscopy of Matrix-Isolated Polycyclic Aromatic Compounds and their Ions. 6; Polycyclic Aromatic Nitrogen Heterocycles

    NASA Technical Reports Server (NTRS)

    Mattioda, A. L.; Hudgins, Douglas M.; Bauschlicher, C. W., Jr.; Rosi, M.; Allamandola, L. J.; DeVincenzi, D. (Technical Monitor)

    2002-01-01

    The matrix-isolation technique has been employed to measure the mid-infrared spectra of several polycyclic aromatic nitrogen heterocycles in both neutral and cationic forms. The species studied include: 7,8 benzoquinoline (C13H9N); 2-azapyrene (C15H9N); 1- and 2-azabenz(a)anthracene (C17H11N); and 1-, 2-, and 4-azachrysene (also C17H11N). The experimentally measured band frequencies and intensities for each molecule are tabulated and compared with their theoretically calculated values computed using density functional theory at the B3LYP/4-31G level. The overall agreement between experiment and theory is quite good, in keeping with previous investigations involving the parent aromatic hydrocarbons. Several interesting spectroscopic trends are found to accompany nitrogen substitution into the aromatic framework of these compounds. First, for the neutral species, the nitrogen atom produces a significant increase in the total integrated infrared intensity across the 1600 - 1100/cm region and plays an essential role in the molecular vibration that underlies an uncharacteristically intense, discrete feature that is observed near 1400/cm in the spectra of 7,8 benzoquinoline, 1-azabenz(a)anthracene, and 4-azachrysene. The origin of this enhanced infrared activity and the nature of the new 1400/cm vibrational mode are explored. Finally, in contrast to the parent hydrocarbon species, these aromatic nitrogen heterocycles possess a significant permanent dipole moment. Consequently, these dipole moments and the rotational constants are reported for these species in their neutral and ionized forms.

  8. Fermentation performances and aroma production of non-conventional wine yeasts are influenced by nitrogen preferences.

    PubMed

    Rollero, Stéphanie; Bloem, Audrey; Ortiz-Julien, Anne; Camarasa, Carole; Divol, Benoit

    2018-05-07

    Saccharomyces cerevisiae is currently the most important yeast involved in food fermentations, particularly in oenology. However, several other yeast species occur naturally in grape must that are highly promising for diversifying and improving the aromatic profile of wines. If the nitrogen requirement of S. cerevisiae has been described in detail, those of non-Saccharomyces yeasts remain poorly studied despite their increasingly widespread use in winemaking. With a view to improving the use of non-Saccharomyces yeasts in winemaking, we explored the fermentation performances, the utilization of nitrogen sources and the volatile compound production of ten strains of non-conventional yeasts in pure culture. Two different conditions were tested: one mimicking the grape juice's nitrogen composition and one with all the nitrogen sources at the same level. We highlighted the diversity in terms of nitrogen preference and amount consumed among the yeast strains. Some nitrogen sources (arginine, glutamate, glycine, tryptophan and GABA) displayed the largest variations between strains throughout the fermentation. Several non-Saccharomyces strains produced important aroma compounds such as higher alcohols, acetate and ethyl esters in significantly higher quantities than S. cerevisiae.

  9. FIREX (Fire Influence on Regional and Global Environments Experiment): Measurements of Nitrogen Containing Volatile Organic Compounds

    NASA Astrophysics Data System (ADS)

    Warneke, C.; Schwarz, J. P.; Yokelson, R. J.; Roberts, J. M.; Koss, A.; Coggon, M.; Yuan, B.; Sekimoto, K.

    2017-12-01

    A combination of a warmer, drier climate with fire-control practices over the last century have produced a situation in which we can expect more frequent fires and fires of larger magnitude in the Western U.S. and Canada. There are urgent needs to better understand the impacts of wildfire and biomass burning (BB) on the atmosphere and climate system, and for policy-relevant science to aid in the process of managing fires. The FIREX (Fire Influence on Regional and Global Environment Experiment) research effort is a multi-year, multi-agency measurement campaign focused on the impact of BB on climate and air quality from western North American wild fires, where research takes place on scales ranging from the flame-front to the global atmosphere. FIREX includes methods development and small- and large-scale laboratory and field experiments. FIREX will include: emission factor measurements from typical North American fuels in the fire science laboratory in Missoula, Montana; mobile laboratory deployments; ground site measurements at sites influenced by BB from several western states. The main FIREX effort will be a large field study with multiple aircraft and mobile labs in the fire season of 2019. One of the main advances of FIREX is the availability of various new measurement techniques that allows for smoke evaluation in unprecedented detail. The first major effort of FIREX was the fire science laboratory measurements in October 2016, where a large number of previously understudied Nitrogen containing volatile organic compounds (NVOCs) were measured using H3O+CIMS and I-CIMS instruments. The contribution of NVOCs to the total reactive Nitrogen budget and the relationship to the Nitrogen content of the fuel are investigated.

  10. 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 consistent with their formation, or formation of their precursors, by interstellar chemistry.

  11. Molecular composition of rainwater and aerosol during rain events in León, Spain, using high resolution mass spectrometry.

    NASA Astrophysics Data System (ADS)

    Fee, Anna

    2017-04-01

    Anna Fee (1), Markus Kalberer (1), Roberto Fraile (2), Amaya Castro (2), Ana. I. Calvo (2), Carlos Blanco-Alegre (2), Fernanda Oduber (2) and Mário Cerqueira (3). 1 Department of Chemistry, University of Cambridge, UK. 2 Department of Applied Chemistry and Physics, IMARENAB, University of León, Spain. 3 Department of Environmental Planning, University of Aveiro, Portugal. A wide range of atmospheric compounds which are present in rainwater are often also present in aerosol. They can be taken up during cloud droplet formation (in-cloud scavenging) or washed out during precipitation (below-cloud scavenging). Such compounds including aromatic hydrocarbons and organic nitrogen containing compounds are hazardous to health. In this study, the organic chemical composition of rainwater and aerosol from rain events in León, Spain, is being analysed using high resolution mass spectrometry. Collected rainwater along with high volume and low volume filters from rain events which occurred during spring, summer and winter of 2016 have been selected for analysis. Rainwater samples were prepared using Polymeric Reversed Phase Solid Phase Extraction (SPE) and filters have been extracted in water with and without SPE. Three different SPE polymer based sorbents were tested; one for extracting neutral compounds and two which are more suitable for extracting organic compounds containing sulphate and other polar functional groups. The sorbent for extracting neutral compounds was found to yield a higher number of compounds from the sample extraction than the other two varieties. Kendrick masses, Van Krevelen plots and carbon oxidation states have been investigated to identify compounds and patterns. Preliminary results show a predominance in peaks with O/C ratios between 0.2 and 0.7 and H/C ratios between 1 and 2 in both rain and aerosol samples which indicates substituted aromatic compounds. Cellulose material and fatty acids may also be present. The rain samples also have a significant number of peaks with O/C ratios of 0.0 and H/C ratios between 0.5 and 1 which appear to be absent from the aerosol. These may be due to condensed aromatic rings and considering local meteorological factors will aid interpretation. More preliminary results show that on average 70% of assigned compounds in the rainwater contain nitrogen and 28% contain sulphur. In the aerosol, 54% of compounds contain nitrogen and 41% contain sulphur. Further analysis is also predicted to reveal significant seasonal trends between rainwater and aerosol samples.

  12. Biochemical upgrading of oils

    DOEpatents

    Premuzic, Eugene T.; Lin, Mow S.

    1999-01-12

    A process for biochemical conversion of heavy crude oils is provided. The process includes contacting heavy crude oils with adapted biocatalysts. The resulting upgraded oil shows, a relative increase in saturated hydrocarbons, emulsions and oxygenates and a decrease in compounds containing in organic sulfur, organic nitrogen and trace metals. Adapted microorganisms which have been modified under challenged growth processes are also disclosed.

  13. Biochemical upgrading of oils

    DOEpatents

    Premuzic, E.T.; Lin, M.S.

    1999-01-12

    A process for biochemical conversion of heavy crude oils is provided. The process includes contacting heavy crude oils with adapted biocatalysts. The resulting upgraded oil shows, a relative increase in saturated hydrocarbons, emulsions and oxygenates and a decrease in compounds containing organic sulfur, organic nitrogen and trace metals. Adapted microorganisms which have been modified under challenged growth processes are also disclosed. 121 figs.

  14. SOIL NITRATE AND AMMONIUM THROUGH 2 YEARS OF SELECTIVE HERBIVORY AND CHRONIC NITROGEN ENRICHMENT

    EPA Science Inventory

    -The effects of increased amounts and flux of bioavailable nitrogenous compounds in the ecosystem is of great interest to ecological researchers and longstanding concern to land-managers. Excess nitrogen in the environment is associated with many large-scale environmental concer...

  15. Production of fermentation aroma compounds by Saccharomyces cerevisiae wine yeasts: effects of yeast assimilable nitrogen on two model strains.

    PubMed

    Carrau, Francisco M; Medina, Karina; Farina, Laura; Boido, Eduardo; Henschke, Paul A; Dellacassa, Eduardo

    2008-11-01

    The contribution of yeast fermentation metabolites to the aromatic profile of wine is well documented; however, the biotechnological application of this knowledge, apart from strain selection, is still rather limited and often contradictory. Understanding and modeling the relationship between nutrient availability and the production of desirable aroma compounds by different strains must be one of the main objectives in the selection of industrial yeasts for the beverage and food industry. In order to overcome the variability in the composition of grape juices, we have used a chemically defined model medium for studying yeast physiological behavior and metabolite production in response to nitrogen supplementation so as to identify an appropriate yeast assimilable nitrogen level for strain differentiation. At low initial nitrogen concentrations, strain KU1 produced higher quantities of esters and fatty acids whereas M522 produced higher concentrations of isoacids, gamma-butyrolactone, higher alcohols and 3-methylthio-1-propanol. We propose that although strains KU1 and M522 have a similar nitrogen consumption profile, they represent useful models for the chemical characterization of wine strains in relation to wine quality. The differential production of aroma compounds by the two strains is discussed in relation to their capacity for nitrogen usage and their impact on winemaking. The results obtained here will help to develop targeted metabolic footprinting methods for the discrimination of industrial yeasts.

  16. 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 threshold as water-soluble free AA, with an average concentration of 22 ± 9 ng m-3 (N=13). Following microwave-assisted gas phase hydrolysis, the total AA concentration in the forest environment increased significantly (70 ± 35 ng m-3) and additional compounds (methionine, isoleucine) were detected above the reporting threshold. The ability to quantify AA in aerosol samples without derivatization reduces time consuming preparation procedures while providing the advancement of selective mass determination that eliminates potential interferences associated with traditional fluorescence detection. This step forward in precise mass determination with the use of internal standardization, improves the confidence of compound identification. With the increasing focus on WSOC (including ON) characterization in the atmospheric science community, native detection by LC-MS (Q-TOF) will play a central role in determining the most direct approach to quantify an increasing fraction of the co-extracted polar organic compounds. Method application for further characterization of atmospheric ON will be discussed. Reference: Samy, S., Robinson, J., and M.D. Hays. "An Advanced LC-MS (Q-TOF) Technique for the Detection of Amino Acids in Atmospheric Aerosols", Analytical Bioanalytical Chemistry, 2011, DOI: 10.1007/s00216-011-5238-2

  17. Polysaccharides, oligosaccharides and nitrogenous compounds change during the ageing of Tempranillo and Verdejo sparkling wines.

    PubMed

    Martínez-Lapuente, Leticia; Apolinar-Valiente, Rafael; Guadalupe, Zenaida; Ayestarán, Belén; Pérez-Magariño, Silvia; Williams, Pascale; Doco, Thierry

    2018-01-01

    Verdejo and Tempranillo are traditional varieties for producing still wines; however, they could provide an alternative for the manufacturing of sparkling wines. Sparkling wines were elaborated by the traditional method, followed by ageing on lees for 9 months. A study on the changes that take place in polysaccharides, oligosaccharides and nitrogenous compounds during the ageing on lees of Tempranillo and Verdejo sparkling wines has been undertaken. Mannoproteins and the glucose residue of oligosaccharides were the major carbohydrates detected in all vinification stages. Yeast polysaccharides and glucan-like structures of the oligosaccharides increased after 3 months of ageing. The evolution of yeast polysaccharides and the composition of PRAG-like structure were different among grape varieties. A decrease in amino acids and biogenic amines was observed during the ageing. The contents of polysaccharides, oligosaccharides and nitrogenous compound were significantly higher in Tempranillo than in Verdejo sparkling wines at the end of the ageing period. Polysaccharides and oligosaccharides from yeast were more significant autolysis markers of sparkling wines than the nitrogenous compounds. Our data suggest a potential cultivar effect on the evolution of yeast polysaccharides and on the composition of PRAG, which may influence the physico-chemical and sensory properties of sparkling wines. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

  18. 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. Copyright © 2015 Elsevier B.V. All rights reserved.

  19. Effect of some nitrogen compounds thermal stability of jet A

    NASA Technical Reports Server (NTRS)

    Antoine, A. C.

    1982-01-01

    The effect of known concentrations of some nitrogen containing compounds on the thermal stability of a conventional fuel, namely, Jet A was investigated. The concentration range from 0.01 to 0.1 wt% nitrogen was examined. Solutions were made containing, individually, pyrrole, indole, quinoline, pyridine, and 4 ethylpyridine at 0.01, 0.03, 0.06, and 0.1 wt% nitrogen concentrations in Jet A. The measurements were all made by using a standard ASTM test for evaluating fuel thermal oxidation behavior, namely, ASTM D3241, 'thermal oxidation stability of turbine fuels (JFTOT procedure).' Measurements were made at two temperature settings, and 'breakpoint temperatures' were determined. The results show that the pyrrole and indole solutions have breakpoint temperatures substantially lower than those of the Jet A used.

  20. The isolation and identification of 6-hydroxycyclohepta-1,4-dione as a novel intermediate in the bacterial degradation of atropine.

    PubMed Central

    Bartholomew, B A; Smith, M J; Long, M T; Darcy, P J; Trudgill, P W; Hopper, D J

    1993-01-01

    Growth of Pseudomonas AT3 on the alkaloid atropine as its sole source of carbon and nitrogen is nitrogen-limited and proceeds by degradation of the tropic acid part of the molecule, with the metabolism of the tropine being limited to the point of release of its nitrogen. A nitrogen-free compound accumulated in the growth medium and was isolated and identified as 6-hydroxycyclohepta-1,4-dione. This novel compound is proposed as an intermediate in tropine metabolism. It served as a growth substrate for the organism and was also the substrate for an NAD(+)-linked dehydrogenase present in cell extracts. The enzyme was induced during the tropine phase of diauxic growth on atropine or during growth on tropine alone. PMID:8328951

  1. Highly Dynamic Cellular-Level Response of Symbiotic Coral to a Sudden Increase in Environmental Nitrogen

    PubMed Central

    Kopp, C.; Pernice, M.; Domart-Coulon, I.; Djediat, C.; Spangenberg, J. E.; Alexander, D. T. L.; Hignette, M.; Meziane, T.; Meibom, A.

    2013-01-01

    ABSTRACT Metabolic interactions with endosymbiotic photosynthetic dinoflagellate Symbiodinium spp. are fundamental to reef-building corals (Scleractinia) thriving in nutrient-poor tropical seas. Yet, detailed understanding at the single-cell level of nutrient assimilation, translocation, and utilization within this fundamental symbiosis is lacking. Using pulse-chase 15N labeling and quantitative ion microprobe isotopic imaging (NanoSIMS; nanoscale secondary-ion mass spectrometry), we visualized these dynamic processes in tissues of the symbiotic coral Pocillopora damicornis at the subcellular level. Assimilation of ammonium, nitrate, and aspartic acid resulted in rapid incorporation of nitrogen into uric acid crystals (after ~45 min), forming temporary N storage sites within the dinoflagellate endosymbionts. Subsequent intracellular remobilization of this metabolite was accompanied by translocation of nitrogenous compounds to the coral host, starting at ~6 h. Within the coral tissue, nitrogen is utilized in specific cellular compartments in all four epithelia, including mucus chambers, Golgi bodies, and vesicles in calicoblastic cells. Our study shows how nitrogen-limited symbiotic corals take advantage of sudden changes in nitrogen availability; this opens new perspectives for functional studies of nutrient storage and remobilization in microbial symbioses in changing reef environments. PMID:23674611

  2. 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.

  3. Sources and behaviour of nitrogen compounds in the shallow groundwater of agricultural areas (Poyang Lake basin, China)

    NASA Astrophysics Data System (ADS)

    Soldatova, Evgeniya; Guseva, Natalia; Sun, Zhanxue; Bychinsky, Valeriy; Boeckx, Pascal; Gao, Bai

    2017-07-01

    Nitrogen contamination of natural water is a typical problem for various territories throughout the world. One of the regions exposed to nitrogen pollution is located in the Poyang Lake basin. As a result of agricultural activity and dense population, the shallow groundwater of this area is characterised by a high concentration of nitrogen compounds, primarily NO3-, with the concentration varying from 0.1 mg/L to 206 mg/L. Locally, high ammonium content occurs in the shallow groundwater with low reduction potential Eh (< 100 mV). However, in general, the shallow groundwater of the Poyang Lake basin has Eh > 100 mV. To identify sources of nitrogen species and the factors that determine their behaviour, the dual stable isotope approach (δ15N and δ18О) and physical-chemical modelling were applied. Actual data were collected by sampling shallow groundwater from domestic water supply wells around the lake. The δ18О values from - 4.1‰ to 13.9‰ with an average value of 5.3 permille indicate a significant influence of nitrification on nitrogen balance. The enrichment of nitrate with the 15N isotope indicates that manure and domestic sewage are the principal sources of nitrogen compounds. Inorganic nitrogen speciation and thermodynamic calculations demonstrate the high stability of nitrate in the studied groundwater. Computer simulation and field observations indicate the reducing conditions formed under joint effects of anthropogenic factors and appropriate natural conditions, such as the low-level topography in which decreased water exchange rate can occur. The simulation also demonstrates the growth in pH of the groundwater as a consequence of fertilisation, which, in turn, conduced to the clay mineral formation at lower concentrations of aqueous clay-forming components than the ones under the natural conditions.

  4. Modeling the Gas Nitriding Process of Low Alloy Steels

    NASA Astrophysics Data System (ADS)

    Yang, M.; Zimmerman, C.; Donahue, D.; Sisson, R. D.

    2013-07-01

    The effort to simulate the nitriding process has been ongoing for the last 20 years. Most of the work has been done to simulate the nitriding process of pure iron. In the present work a series of experiments have been done to understand the effects of the nitriding process parameters such as the nitriding potential, temperature, and time as well as surface condition on the gas nitriding process for the steels. The compound layer growth model has been developed to simulate the nitriding process of AISI 4140 steel. In this paper the fundamentals of the model are presented and discussed including the kinetics of compound layer growth and the determination of the nitrogen diffusivity in the diffusion zone. The excellent agreements have been achieved for both as-washed and pre-oxided nitrided AISI 4140 between the experimental data and simulation results. The nitrogen diffusivity in the diffusion zone is determined to be constant and only depends on the nitriding temperature, which is ~5 × 10-9 cm2/s at 548 °C. It proves the concept of utilizing the compound layer growth model in other steels. The nitriding process of various steels can thus be modeled and predicted in the future.

  5. [New natural products from the marine-derived Aspergillus fungi-A review].

    PubMed

    Zhao, Chengying; Liu, Haishan; Zhu, Weiming

    2016-03-04

    Marine-derived fungi were the main source of marine microbial natural products (NPs) due to their complex genetic background, chemodiversity and high yield of NPs. According to our previous survey for marine microbial NPs from 2010 to 2013, Aspergillus fungi have received the most of attention among all the marine-derived fungi, which accounted for 31% NPs of the marine fungal origins. This paper reviewed the sources, chemical structures and bioactivites of all the 512 new marine NPs of Aspergillus fungal origins from 1992 to 2014. These marine NPs have diverse chemical structures including polyketides, fatty acids, sterols and terpenoids, alkaloids, peptides, and so on, 36% of which displayed bioactivities such as cytotoxicity, antimicrobial activity, antioxidant and insecticidal activity. Nitrogen compounds are the major secondary metabolites accounting for 52% NPs from the marine-derived Aspergillus fungi. Nitrogen compounds are also the class with the highest ratio of bioactive compounds, 40% of which are bioactive. Plinabulin, a dehydrodiketopiperazine derivative of halimide had been ended its phase II trial and has received its phase III study from the third quarter of 2015 for the treatment of advanced, metastatic non-small cell lung cancer.

  6. 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.

  7. Palladium-Catalyzed Dynamic Kinetic Asymmetric Transformations of Vinyl Aziridines with Nitrogen Heterocycles: Rapid Access to Biologically Active Pyrroles and Indoles

    PubMed Central

    Trost, Barry M.; Osipov, Maksim; Dong, Guangbin

    2010-01-01

    We report that nitrogen heterocycles can serve as competent nucleophiles in the palladium-catalyzed dynamic kinetic asymmetric alkylation of vinyl aziridines. The resulting alkylated products were obtained with high regio-, chemo-, and enantioselectivity. Both substituted 1H-pyrroles and 1H-indoles were successfully employed to give exclusively the branched N-alkylated products. The synthetic utility of this process was demonstrated by applying this method to the preparation of several medicinal chemistry lead compounds and bromopyrrole alkaloids including longamide B, longamide B methyl ester, hanishin, agesamides A and B, and cyclooroidin. PMID:20949972

  8. An Exploratory Research and Development Program Leading to Specifications for Aviation Turbine Fuel from Whole Crude Shale Oil. Part V.

    DTIC Science & Technology

    1982-03-01

    Velocity LP Linear Program LP Sep Low Pressure Separator Mo Molybdenum N2 Nitrogen Gas NA Not Available NH3 Ammonia Gas xiv LIST OF SYMBOLS AND...part, is present as heterocyclic compounds. It is reduced to ammonia and re- moved as such or the heterocyclic compounds are saturated to basic nitro...the carbon-nitrogen bond and then removing the nitrogen from the amine as ammonia .(4) -2- ------- C5HI 1 NH2 +H2 -5l H . - 2C5H2 + NH3 N N H It can be

  9. Possible sources of nitrate in ground water at swine licensed-managed feeding operations in Oklahoma, 2001

    USGS Publications Warehouse

    Becker, Mark F.; Peter, Kathy D.; Masoner, Jason

    2002-01-01

    Samples collected and analyzed by the Oklahoma Department of Agriculture, Food, and Forestry from 1999 to 2001 determined that nitrate exceeded the U.S. Environmental Protection Agency maximum contaminant level for public drinking-water supplies of 10 milligrams per liter as nitrogen in 79 monitoring wells at 35 swine licensed-managed feeding operations (LMFO) in Oklahoma. The LMFOs are located in rural agricultural settings where long-term agriculture has potentially affected the ground-water quality in some areas. Land use prior to the construction of the LMFOs was assessed to evaluate the types of agricultural land use within a 500-meter radius of the sampled wells. Chemical and microbiological techniques were used to determine the possible sources of nitrate in water sampled from 10 wastewater lagoons and 79 wells. Samples were analyzed for dissolved major ions, dissolved trace elements, dissolved nutrients, nitrogen isotope ratios of nitrate and ammonia, wastewater organic compounds, and fecal coliform bacteria. Bacteria ribotyping analysis was done on selected samples to identify possible specific animal sources. A decision process was developed to identify the possible sources of nitrate. First, nitrogen isotope ratios were used to define sources as animal, mixed animal and fertilizer, or fertilizer. Second, wastewater organic compound detections, nitrogen-isotope ratios, fecal coliform bacteria detections, and ribotyping were used to refine the identification of possible sources as LFMO waste, fertilizer, or unidentified animal or mixtures of these sources. Additional evidence provided by ribotyping and wastewater organic compound data can, in some cases, specifically indicate the animal source. Detections of three or more wastewater organic compounds that are indicators of animal sources and detections of fecal coliform bacteria provided additional evidence of an animal source. LMFO waste was designated as a possible source of nitrate in water from 10 wells. The source of waste in water from five of those wells was determined through ribotyping, and the source of waste in water from the remaining five wells was determined by detections of three or more animal-waste compounds in the well samples. LMFO waste in the water from wells with unidentified animal source of nitrate does not indicate that LMFO waste was not the source, but indicated that multiple animal sources, including LMFO waste, may be the source of the nitrate.

  10. Alterations in nitrogen metabolites after putrescine treatment in alfalfa under drought stress.

    PubMed

    Zeid, I M; Shedeed, Z A

    2007-05-01

    Alfalfa (Medicago sativa, Siwa 1) seeds were subjected to drought stress during germination by using polyethylene glycol (PEG 4000) for studying the changes in some enzyme activities involved in nitrogen metabolism and the content of nitrogenous compounds during the first four days of growth after putrescine (Put) treatment. Decreasing the external water potential reduced activities of glutamate-pyruvate transferase (GPT), glutamate-oxaloacetate transferase (GOT) and RNase. Some free amino acids such as proline and glycine increased, while alanine and aspartic acid decreased. Nucleic acids content also decreased. Polyamines e.g., spermidine (Spd) and spermine (Spm) increased at the water potential -0.4 MPa. Put treatment increased activities of GOT, GPT and RNase. Furthermore, Put treatment increased nucleic acids content and the endogenous polyamines under drought stress. Drought stress was imposed during seedling stage by decreasing soil moisture content. GOT, GPT and RNase activities increased in leaves of alfalfa seedlings under drought stress. Soluble nitrogenous compounds accumulated under drought stress, while nucleic acids content decreased. Except glutamic acid, all free amino acids detected increased under drought stress. Put treatment decreased activities of GOT, GPT and RNase, as well as reduced the accumulation of the total soluble nitrogenous compounds, but increased DNA, RNA and protein contents.

  11. Extraction of brewer's yeasts using different methods of cell disruption for practical biodiesel production.

    PubMed

    Řezanka, Tomáš; Matoulková, Dagmar; Kolouchová, Irena; Masák, Jan; Viden, Ivan; Sigler, Karel

    2015-05-01

    The methods of preparation of fatty acids from brewer's yeast and its use in production of biofuels and in different branches of industry are described. Isolation of fatty acids from cell lipids includes cell disintegration (e.g., with liquid nitrogen, KOH, NaOH, petroleum ether, nitrogenous basic compounds, etc.) and subsequent processing of extracted lipids, including analysis of fatty acid and computing of biodiesel properties such as viscosity, density, cloud point, and cetane number. Methyl esters obtained from brewer's waste yeast are well suited for the production of biodiesel. All 49 samples (7 breweries and 7 methods) meet the requirements for biodiesel quality in both the composition of fatty acids and the properties of the biofuel required by the US and EU standards.

  12. Nitrogen and Sulfur Requirements for Clostridium thermocellum and Caldicellulosiruptor bescii on Cellulosic Substrates in Minimal Nutrient Media

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Kridelbaugh, Donna M; Nelson, Josh C; Engle, Nancy L

    2013-01-01

    Growth media for cellulolytic Clostridium thermocellum and Caldicellulosiruptor bescii bacteria usually contain excess nutrients that would increase costs for consolidated bioprocessing for biofuel production and create a waste stream with nitrogen, sulfur and phosphate. C. thermocellum was grown on crystalline cellulose with varying concentrations of nitrogen and sulfur compounds, and growth rate and alcohol production response curves were determined. Both bacteria assimilated sulfate in the presence of ascorbate reductant, increasing the ratio of oxidized to reduced fermentation products. From these results, a low ionic strength, defined minimal nutrient medium with decreased nitrogen, sulfur, phosphate and vitamin supplements was developed formore » the fermentation of cellobiose, cellulose and acid-pretreated Populus. Carbon and electron balance calculations indicate the unidentified residual fermentation products must include highly reduced molecules. Both bacterial populations were maintained in co-cultures with substrates containing xylan or hemicellulose in defined medium with sulfate and basal vitamin supplements.« less

  13. TRANC - a novel fast-response converter to measure total reactive atmospheric nitrogen

    NASA Astrophysics Data System (ADS)

    Marx, O.; Brümmer, C.; Ammann, C.; Wolff, V.; Freibauer, A.

    2012-05-01

    The input and loss of plant available nitrogen (reactive nitrogen: Nr) from/to the atmosphere can be an important factor for the productivity of ecosystems and thus for its carbon and greenhouse gas exchange. We present a novel converter for reactive nitrogen (TRANC: Total Reactive Atmospheric Nitrogen Converter), which offers the opportunity to quantify the sum of all airborne reactive nitrogen compounds (∑Nr) in high time resolution. The basic concept of the TRANC is the full conversion of all Nr to nitrogen monoxide (NO) within two reaction steps. Initially, reduced Nr compounds are being oxidised, and oxidised Nr compounds are thermally converted to lower oxidation states. Particulate Nr is being sublimated and oxidised or reduced afterwards. In a second step, remaining higher nitrogen oxides or those generated in the first step are catalytically converted to NO with carbon monoxide used as reduction gas. The converter is combined with a fast response chemiluminescence detector (CLD) for NO analysis and its performance was tested for the most relevant gaseous and particulate Nr species under both laboratory and field conditions. Recovery rates during laboratory tests for NH3 and NO2 were found to be 95 and 99%, respectively, and 97% when the two gases were combined. In-field longterm stability over an 11-month period was approved by a value of 91% for NO2. Effective conversion was also found for ammonium and nitrate containing particles. The recovery rate of total ambient Nr was tested against the sum of individual measurements of NH3, HNO3, HONO, NH4+, NO3-, and NOx using a combination of different well-established devices. The results show that the TRANC-CLD system precisely captures fluctuations in ∑Nr concentrations and also matches the sum of all individual Nr compounds measured by the different single techniques. The TRANC features a specific design with very short distance between the sample air inlet and the place where the thermal and catalytic conversions to NO occur. This assures a short residence time of the sample air inside the instrument, and minimises wall sorption problems of water soluble compounds. The fast response time (e-folding times of 0.30 to 0.35 s were found during concentration step changes) and high accuracy in capturing the dominant Nr species enables the converter to be used in an eddy covariance setup. Although a source attribution of specific Nr compounds is not possible, the TRANC is a new reliable tool for permanent measurements of the net ∑Nr flux between ecosystem and atmosphere at a relatively low maintenance and reasonable cost level allowing for diurnal, seasonal and annual investigations.

  14. Total nitrogen and total phosphorus removal from brackish aquaculture wastewater using effective microorganism

    NASA Astrophysics Data System (ADS)

    Mohamad, K. A.; Mohd, S. Y.; Sarah, R. S.; Mohd, H. Z.; Rasyidah, A.

    2017-09-01

    Aquaculture is one of dominant food based industry in the world with 8.3% annual growth rate and its development had led to adverse effect on the environment. High nutrient production in form of nitrogenous compound and phosphorus contributed to environmental deterioration such as eutrophication and toxicity to the industry. Usage of Effective Microorganism (EM), one of the biological approaches to remove Total Nitrogen (TN) and Total Phosphorus (TP) in aquaculture pond was proposed. Samples were obtained from the Sea Bass intensive brackish aquaculture wastewater (AW) from fish farm at Juru, Penang and the parameters used to measure the removal of nitrogenous compounds include, pH, EM dosage, shaking, contact time and optimum variable conditions. From the study, for effective contact time, day 6 is the optimum contact time for both TN and TP with 99.74% and 62.78% removal respectively while in terms of optimum pH, the highest TN removal was at pH 7 with 66.89 %. The optimum dosage of EM is 1.5 ml with ratio 1:166 for 81.5 % TN removal was also found appropriate during the experiment. At varied optimum conditions of EM, the removal efficiency of TN and TP were 81.53% and 38.94% respectively while the removal mechanism of TN was highly dependent on the decomposition rate of specific bacteria such as Nitrobacter bacteria, Yeast and Bacillus Subtilis sp. The study has established the efficacy of EM's ability to treat excessive nutrient of TN and TP from AW.

  15. Membrane bioreactor treatment of a simulated metalworking fluid wastewater containing ethylenediaminetetraacetic acid and dicyclohexylamine.

    PubMed

    Anderson, James E; Lofton, Tiffany V; Kim, Byung R; Mueller, Sherry A

    2009-04-01

    Membrane bioreactors (MBRs) have been installed at automotive plants to treat metalworking fluid (MWF) wastewaters, which are known to contain toxic and/or recalcitrant organic compounds. A laboratory study was conducted to evaluate treatment of a simulated wastewater prepared from a semisynthetic MWF, which contains two such compounds, dicyclohexylamine (DCHA) and ethylenediaminetetraacetic acid (EDTA). Primary findings were as follows: During stable operating periods, almost all chemical oxygen demand (COD), total Kjeldahl nitrogen (TKN), and EDTA were removed (by > 96%). During somewhat unstable periods, COD removal was still extremely robust, but removal of EDTA and TKN were sensitive to prolonged episodes of low dissolved oxygen. Nitrogen mass balance suggested 30 to 40% TKN removal by assimilation and 60 to 70% by nitrification (including up to 34% TKN removal via subsequent denitrification). Dicyclohexylamine appeared to be readily biodegraded. Maximum DCHA and EDTA degradation rates between pH 7 and 8 were found. An Arthrobacter sp. capable of growth on DCHA as the sole source of carbon and energy was isolated.

  16. Hydrogen Storage Materials for Mobile and Stationary Applications: Current State of the Art.

    PubMed

    Lai, Qiwen; Paskevicius, Mark; Sheppard, Drew A; Buckley, Craig E; Thornton, Aaron W; Hill, Matthew R; Gu, Qinfen; Mao, Jianfeng; Huang, Zhenguo; Liu, Hua Kun; Guo, Zaiping; Banerjee, Amitava; Chakraborty, Sudip; Ahuja, Rajeev; Aguey-Zinsou, Kondo-Francois

    2015-09-07

    One of the limitations to the widespread use of hydrogen as an energy carrier is its storage in a safe and compact form. Herein, recent developments in effective high-capacity hydrogen storage materials are reviewed, with a special emphasis on light compounds, including those based on organic porous structures, boron, nitrogen, and aluminum. These elements and their related compounds hold the promise of high, reversible, and practical hydrogen storage capacity for mobile applications, including vehicles and portable power equipment, but also for the large scale and distributed storage of energy for stationary applications. Current understanding of the fundamental principles that govern the interaction of hydrogen with these light compounds is summarized, as well as basic strategies to meet practical targets of hydrogen uptake and release. The limitation of these strategies and current understanding is also discussed and new directions proposed. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  17. Preparation of 2-hydroxy-5-oxoproline and analogs thereof

    DOEpatents

    Martinez, Rodolfo A.; Unkefer, Pat J.

    2001-01-01

    The compound 2-hydroxy-5-oxoproline and analogs thereof may be used to produce an increase in carbon dioxide fixation, growth, dry weight, nutritional value (proteins and amino acids), nodulation and nitrogen fixation and photosynthetically derived chemical energy when applied to plants through their roots and/or through their foliar portions. The present invention includes an essentially quantitative chemical synthesis for this compound which is performed in a single step reaction of Fremy's Salt (potassium nitrosodisulphonate) with either glutamine or 2-pyrrolidone-5-carboxylic acid. Fremy's salt (potassium nitrosodisulphonate) is available commercially, or can be readily synthesized.

  18. Ionization Mechanism of Positive-Ion Nitrogen Direct Analysis in Real Time.

    PubMed

    Song, Liguo; Chuah, Wei Chean; Lu, Xinyi; Remsen, Edward; Bartmess, John E

    2018-04-01

    Nitrogen can be an inexpensive alternative to helium used by direct analysis in real time (DART), especially in consideration of the looming helium shortage. Therefore, the ionization mechanism of positive-ion N 2 DART has been systematically investigated. Our experiments suggest that a range of metastable nitrogen species with a variety of internal energies existed and all of them were less energetic than metastable helium atoms. However, compounds with ionization energies (IE) equal to or lower than 10.2 eV (all organic compounds except the extremely small ones) can be efficiently ionized. Because N 2 DART was unable to efficiently ionize ambient moisture and common organic solvents such as methanol and acetonitrile, the most important ionization mechanism was direct Penning ionization followed by self-protonation of polar compounds generating [M+H] + ions. On the other hand, N 2 DART was able to efficiently ionize ammonia, which was beneficial in the ionization of hydrogen-bonding compounds with proton affinities (PA) weaker than ammonia generating [M+NH 4 ] + ions and large PAHs generating [M+H] + ions through proton transfer. N 2 DART was also able to efficiently ionize NO, which led to the ionization of nonpolar compounds such as alkanes and small aromatics generating [M-(2m+1)H] + (m=0,1…) ions. Lastly, metastable nitrogen species was also able to produce oxygen atoms, which resulted in increased oxygen adducts as the polarity of organic compounds decreased. In comparison with He DART, N 2 DART was approximately one order of magnitude less sensitive in generating [M+H] + ions, but could be more sensitive in generating [M+NH 4 ] + ions. Graphical Abstract ᅟ.

  19. Ionization Mechanism of Positive-Ion Nitrogen Direct Analysis in Real Time

    NASA Astrophysics Data System (ADS)

    Song, Liguo; Chuah, Wei Chean; Lu, Xinyi; Remsen, Edward; Bartmess, John E.

    2018-02-01

    Nitrogen can be an inexpensive alternative to helium used by direct analysis in real time (DART), especially in consideration of the looming helium shortage. Therefore, the ionization mechanism of positive-ion N2 DART has been systematically investigated. Our experiments suggest that a range of metastable nitrogen species with a variety of internal energies existed and all of them were less energetic than metastable helium atoms. However, compounds with ionization energies (IE) equal to or lower than 10.2 eV (all organic compounds except the extremely small ones) can be efficiently ionized. Because N2 DART was unable to efficiently ionize ambient moisture and common organic solvents such as methanol and acetonitrile, the most important ionization mechanism was direct Penning ionization followed by self-protonation of polar compounds generating [M+H]+ ions. On the other hand, N2 DART was able to efficiently ionize ammonia, which was beneficial in the ionization of hydrogen-bonding compounds with proton affinities (PA) weaker than ammonia generating [M+NH4]+ ions and large PAHs generating [M+H]+ ions through proton transfer. N2 DART was also able to efficiently ionize NO, which led to the ionization of nonpolar compounds such as alkanes and small aromatics generating [M-(2m+1)H]+ (m=0,1…) ions. Lastly, metastable nitrogen species was also able to produce oxygen atoms, which resulted in increased oxygen adducts as the polarity of organic compounds decreased. In comparison with He DART, N2 DART was approximately one order of magnitude less sensitive in generating [M+H]+ ions, but could be more sensitive in generating [M+NH4]+ ions. [Figure not available: see fulltext.

  20. Thermodynamic Routes to Novel Metastable Nitrogen-Rich Nitrides

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Sun, Wenhao; Holder, Aaron; Orvañanos, Bernardo

    Compared to oxides, the nitrides are relatively unexplored, making them a promising chemical space for novel materials discovery. Of particular interest are nitrogen-rich nitrides, which often possess useful semiconducting properties for electronic and optoelectronic applications. However, such nitrogen-rich compounds are generally metastable, and the lack of a guiding theory for their synthesis has limited their exploration. Here, we review the remarkable metastability of observed nitrides, and examine the thermodynamics of how reactive nitrogen precursors can stabilize metastable nitrogen-rich compositions during materials synthesis. We map these thermodynamic strategies onto a predictive computational search, training a data-mined ionic substitution algorithm specifically formore » nitride discovery, which we combine with grand-canonical DFT-SCAN phase stability calculations to compute stabilizing nitrogen chemical potentials. We identify several new nitrogen-rich binary nitrides for experimental investigation, notably the transition metal nitrides Mn3N4, Cr3N4, V3N4, and Nb3N5, the main group nitride SbN, and the pernitrides FeN2, CrN2, and Cu2N2. By formulating rational thermodynamic routes to metastable compounds, we expand the search space for functional technological materials beyond equilibrium phases and compositions.« less

  1. Thermodynamic Routes to Novel Metastable Nitrogen-Rich Nitrides

    DOE PAGES

    Sun, Wenhao; Holder, Aaron; Orvañanos, Bernardo; ...

    2017-07-17

    Compared to oxides, the nitrides are relatively unexplored, making them a promising chemical space for novel materials discovery. Of particular interest are nitrogen-rich nitrides, which often possess useful semiconducting properties for electronic and optoelectronic applications. However, such nitrogen-rich compounds are generally metastable, and the lack of a guiding theory for their synthesis has limited their exploration. Here, we review the remarkable metastability of observed nitrides, and examine the thermodynamics of how reactive nitrogen precursors can stabilize metastable nitrogen-rich compositions during materials synthesis. We map these thermodynamic strategies onto a predictive computational search, training a data-mined ionic substitution algorithm specifically formore » nitride discovery, which we combine with grand-canonical DFT-SCAN phase stability calculations to compute stabilizing nitrogen chemical potentials. We identify several new nitrogen-rich binary nitrides for experimental investigation, notably the transition metal nitrides Mn3N4, Cr3N4, V3N4, and Nb3N5, the main group nitride SbN, and the pernitrides FeN2, CrN2, and Cu2N2. By formulating rational thermodynamic routes to metastable compounds, we expand the search space for functional technological materials beyond equilibrium phases and compositions.« less

  2. RELATIONS BETWEEN BACTERIAL NITROGEN METABOLISM AND GROWTH EFFICIENCY IN AN ESTUARINE AND AN OPEN-WATER ECOSYSTEM

    EPA Science Inventory

    Bacterial uptake or release of dissolved nitrogen compounds (amino nitrogen, urea, ammonium and nitrate) were examined in 0.8 |m filtered water from an estuary (Santa Rosa Sound [SRS], northwestern Florida) and an open-water location in the Gulf of Mexico [GM]. The bacterial nutr...

  3. Foliar and fungal 15N: 14N ratios reflect development of mycorrhizae and nitrogen supply during primary succession: testing analytical models.

    Treesearch

    Erik A. Hobbie; Ari Jumpponen; Jim Trappe

    2005-01-01

    Nitrogen isotopes (15N/14N ratios, expressed as δ15N values) are useful markers of the mycorrhizal role in plant nitrogen supply because discrimination against 15N during creation of transfer compounds within mycorrhizal fungi decreases the 15N/...

  4. Method of removing nitrogen monoxide from a nitrogen monoxide-containing gas using a water-soluble iron ion-dithiocarbamate, xanthate or thioxanthate

    DOEpatents

    Liu, D. Kwok-Keung; Chang, Shih-Ger

    1987-08-25

    The present invention relates to a method of removing of nitrogen monoxide from a nitrogen monoxide-containing gas which method comprises contacting a nitrogen oxide-containing gas with an aqueous solution of water soluble organic compound-iron ion chelate complex. The NO absorption efficiency of ferrous urea-dithiocarbamate and ferrous diethanolamine-xanthate as a function of time, oxygen content and solution ph is presented. 3 figs., 1 tab.

  5. Seed germination in response to chemicals: effect of nitrogen and pH in the media.

    PubMed

    Pérez-Fernández, M A; Calvo-Magro, E; Montanero-Fernández, J; Oyola-Velasco, J A

    2006-01-01

    Seed germination generally presents a peak in the next growing season after a fire. Among other factors associated with fire are the increase of soil nitrogen and changes in the pH of the soil. In this study, we addressed the question, whether or not the germination response of eight species is linked with the increase in pH and nitrogenous compounds in the germination media? We assessed the separate and combined effects of nitrogenous compounds and pH on the percentage and rate of germination of seeds of Medicago arabica (L.) Hudson, Epilobium hirsutum L., Foeniculum vulgare Miller, Daucus carota L., Thapsia villosa L., Cynosurus cristatus L., Dactylis glomerata L. and Rumex crispus L. All these species are well represented in the Mediterranean ecosystems of the central-west Spain. Water and CaCl2 were used as controls. Nitrogenous compounds increased percent germination (level) and rate in three of the species studied. High pH negatively affected the germination rate of seeds from most species, but had no effect on the per cent germination of any of the species. The higher concentration of the nutritious solutions affected negatively the germination level and rate. The different germination responses of seeds of the studied species could not be exclusively attributed to pH values in the media, whereas the amount and form of Nitrogen in the media has a greater effect on it. These differences in germination are species dependent.

  6. Modeling the long-term fate of agricultural nitrate in groundwater in the San Joaquin Valley, California

    USGS Publications Warehouse

    Chapelle, Francis H.; Campbell, Bruce G.; Widdowson, Mark A.; Landon, Mathew K.

    2013-01-01

    Nitrate contamination of groundwater systems used for human water supplies is a major environmental problem in many parts of the world. Fertilizers containing a variety of reduced nitrogen compounds are commonly added to soils to increase agricultural yields. But the amount of nitrogen added during fertilization typically exceeds the amount of nitrogen taken up by crops. Oxidation of reduced nitrogen compounds present in residual fertilizers can produce substantial amounts of nitrate which can be transported to the underlying water table. Because nitrate concentrations exceeding 10 mg/L in drinking water can have a variety of deleterious effects for humans, agriculturally derived nitrate contamination of groundwater can be a serious public health issue. The Central Valley aquifer of California accounts for 13 percent of all the groundwater withdrawals in the United States. The Central Valley, which includes the San Joaquin Valley, is one of the most productive agricultural areas in the world and much of this groundwater is used for crop irrigation. However, rapid urbanization has led to increasing groundwater withdrawals for municipal public water supplies. That, in turn, has led to concern about how contaminants associated with agricultural practices will affect the chemical quality of groundwater in the San Joaquin Valley. Crop fertilization with various forms of nitrogen-containing compounds can greatly increase agricultural yields. However, leaching of nitrate from soils due to irrigation has led to substantial nitrate contamination of shallow groundwater. That shallow nitrate-contaminated groundwater has been moving deeper into the Central Valley aquifer since the 1960s. Denitrification can be an important process limiting the mobility of nitrate in groundwater systems. However, substantial denitrification requires adequate sources of electron donors in order to drive the process. In many cases, dissolved organic carbon (DOC) and particulate organic carbon (POC) are the primary electron donors driving active denitrification in groundwater. The purpose of this chapter is to use a numerical mass balance modeling approach to quantitatively compare sources of electron donors (DOC, POC) and electron acceptors (dissolved oxygen, nitrate, and ferric iron) in order to assess the potential for denitrification to attenuate nitrate migration in the Central Valley aquifer.

  7. Chemical-meteorological aspects of some atmospheric nitrogen compounds in the tropics (CUBA)

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Cuesta Santos, O.A.; Ortiz Bulto, P.L.; Hurtado, M.S.

    The transboundary problems of global and regional atmospheric pollution are at current time, a concern of scientific community and environmentalist, so our region is not considered as an exception on this matter. In our monitoring stations, some studies confirming the presence of nitrogen compounds connected with long range transport have been undertaken. For such reason, the interesting tropospheric chemistry reactions shall be verified. The above mentioned studies include the analysis of NO{sub x} (NO + NO{sub 2}), NH{sub 3}, nitrate and ammonium concentrations in aerosols and rainfall in some monitoring stations its connection with the Kinds of Synoptic Situations (KSS)more » and the research on back tracks, so all this allows to know its possible sources of origin. As a result of interest it has been found that the total deposition of these compounds oscillates between 0,706 an d3,317 g.m{sup -2} year{sup -1}. The wet deposition exhibits approximately 60%, while the dry one is of 40%. The weight of both depositions depends on our tropical rainy climate`s features. On the other hand, the oxidized nitrogen forms only give 40%, while the reduced ones 60% of total. This coincides more with the power of natural sources in accordance with our climate. The nitrate`s concentrations in aerosols and rainfall connected with Continental Migratory Anticyclone have the higher values than with remaining kinds of synoptic situations influencing on our territory, so it can be concluded that there is transport of these pollutants from continent.« less

  8. Regiochemistry in cobalt-mediated intermolecular Pauson-Khand reactions of unsymmetrical internal heteroaromatic alkynes with norbornene.

    PubMed

    Moulton, Benjamin E; Whitwood, Adrian C; Duhme-Klair, Anne K; Lynam, Jason M; Fairlamb, Ian J S

    2011-07-01

    The intermolecular Pauson-Khand (PK) reactions of sterically comparable (2-phenylethynyl)heteroaromatic compounds with norbornene, mediated by Co(2)(CO)(8) to give cyclopentenone products, were examined in this study. A synthetic protocol utilizing focused-microwave dielectric heating proved indispensable in the efficient synthesis of the PK cyclopentenone products. "π-Deficient" heteroaromatic substrates, e.g., 2-pyrones, and some "π-excessive" heteroaromatics such as 2- and 3-thiophene and 2-furan favor the β-position in the newly formed cyclopentenone ring. Other π-excessive heteroaromatics such as 2-pyrrole or 2-indole favor the α-position. A π-excessive 3-indole derivative gave a nearly equal mixture of regioisomers. The position of the nitrogen in pyridyl-containing alkyne substrates also affects the regiochemical outcome of the PK reaction. A 2-pyridyl alkyne, possessing a proximal nitrogen, influences the regioselectivity relative to a 4-pyridyl variant quite dramatically, favoring the β-position in the newly formed cyclopentenone ring. A 2-pyrimidylalkyne exhibits similar behavior to the 2-pyridylalkyne. Compounds that do not participate in PK reactions with norbornene include (2-phenylethynyl)imidazoles and the related benzimidazoles, which promote rapid decomposition of the in situ generated (μ(2)-alkyne)Co(2)(CO)(6) complexes. This stands in contrast with other nitrogen-containing heteroaromatics, e.g., pyrrole-, indole-, and pyrimidine-derived compounds, which effectively undergo PK reactions. Overall, the type of heteroaromatic group dramatically influences PK regioselectivity, which can in part be explained by rationalization of the current reaction mechanism, but not fully.

  9. Titan Upper Atmosphere: A factory of hydrocarbons

    NASA Image and Video Library

    2005-04-22

    During its closest flyby of Saturn's moon Titan on April 16, the Cassini spacecraft came within 1,025 kilometers (637 miles) of the moon's surface and found that the outer layer of the thick, hazy atmosphere is brimming with complex hydrocarbons. This figure shows a mass spectrum of Titan's ionosphere near 1,200 kilometers (746 miles) above its surface. The mass range covered goes from hydrogen at 1 atomic mass unit per elementary charge (Dalton) to 99 Daltons. This mass range includes compounds with 1, 2, 3, 4, 5, 6, and 7 carbons as the base structure (as indicated in the figure label). The identified compounds include multiple carbon molecules and carbon-nitrogen bearing species as well. http://photojournal.jpl.nasa.gov/catalog/PIA07865

  10. Improving Model Representation of Reduced Nitrogen in the Greater Yellowstone Area

    NASA Astrophysics Data System (ADS)

    Thompson, T. M.

    2015-12-01

    Human activity, including fossil fuel combustion and agriculture has greatly increased the amount of reactive nitrogen (RN) in the atmosphere and its subsequent deposition to land. Increases in deposition of RN compounds can adversely affect sensitive ecosystems and is a growing problem in many natural areas. The National Park Service in conjunction with Colorado State University researchers and assistance from the Forest Service conducted the Grand Teton Reactive Nitrogen Deposition Study (GrandTReNDS) involving spatially and temporally detailed measurements of RN during spring/summer 2011. In this work it was found that during summer months at the high elevation site Grand Targhee, 62% of the nitrogen deposition was due to reduced nitrogen, about equally split between dry and wet deposition, oxidized nitrogen accounted for 27% of the total, and the remaining was wet deposited organic nitrogen. An important next step to GrandTReNDS is the use of chemical transport models (CTMs) to estimate source contributions to RN in the park. Given the large contribution of reduced nitrogen species to total nitrogen deposition in the park, understanding and properly characterizing ammonia in CTMs is critical to estimating the total nitrogen deposition. A model performance evaluation of the CAMx uni-directional model and CMAQ bi-direction and uni-directional 2011 model simulations versus GrandTReNDS and other datasets was conducted. Preliminary results suggest that, in some areas, model performance of ambient ammonia concentration is more sensitive to the spatial resolution of the model and the accuracy of the spatial representation of emissions than to the incorporation of bi-directional flux. Additional model sensitivity runs, including sensitivity to resolution (with and without bi-directional flux capabilities), changes to model estimated ammonia dry deposition velocities, and improved representation of the spatial distribution of ammonia emissions, are used to identify the best set of options for GrandTReNDS modeling, and to provide a measure of uncertainties. This will help atmospheric scientists identify deficiencies in the models and inform future model development.

  11. The Impact of Single Amino Acids on Growth and Volatile Aroma Production by Saccharomyces cerevisiae Strains

    PubMed Central

    Fairbairn, Samantha; McKinnon, Alexander; Musarurwa, Hannibal T.; Ferreira, António C.; Bauer, Florian F.

    2017-01-01

    Nitrogen availability and utilization by Saccharomyces cerevisiae significantly influence fermentation kinetics and the production of volatile compounds important for wine aroma. Amino acids are the most important nitrogen source and have been classified based on how well they support growth. This study evaluated the effect of single amino acids on growth kinetics and major volatile production of two phenotypically different commercial wine yeast strains in synthetic grape must. Four growth parameters, lag phase, maximum growth rate, total biomass formation and time to complete fermentation were evaluated. In contrast with previous findings, in fermentative conditions, phenylalanine and valine supported growth well and asparagine supported it poorly. The four parameters showed good correlations for most amino acid treatments, with some notable exceptions. Single amino acid treatments resulted in the predictable production of aromatic compounds, with a linear correlation between amino acid concentration and the concentration of aromatic compounds that are directly derived from these amino acids. With the increased complexity of nitrogen sources, linear correlations were lost and aroma production became unpredictable. However, even in complex medium minor changes in amino acid concentration continued to directly impact the formation of aromatic compounds, suggesting that the relative concentration of individual amino acids remains a predictor of aromatic outputs, independently of the complexity of metabolic interactions between carbon and nitrogen metabolism and between amino acid degradation and utilization pathways. PMID:29312237

  12. The Impact of Single Amino Acids on Growth and Volatile Aroma Production by Saccharomyces cerevisiae Strains.

    PubMed

    Fairbairn, Samantha; McKinnon, Alexander; Musarurwa, Hannibal T; Ferreira, António C; Bauer, Florian F

    2017-01-01

    Nitrogen availability and utilization by Saccharomyces cerevisiae significantly influence fermentation kinetics and the production of volatile compounds important for wine aroma. Amino acids are the most important nitrogen source and have been classified based on how well they support growth. This study evaluated the effect of single amino acids on growth kinetics and major volatile production of two phenotypically different commercial wine yeast strains in synthetic grape must. Four growth parameters, lag phase, maximum growth rate, total biomass formation and time to complete fermentation were evaluated. In contrast with previous findings, in fermentative conditions, phenylalanine and valine supported growth well and asparagine supported it poorly. The four parameters showed good correlations for most amino acid treatments, with some notable exceptions. Single amino acid treatments resulted in the predictable production of aromatic compounds, with a linear correlation between amino acid concentration and the concentration of aromatic compounds that are directly derived from these amino acids. With the increased complexity of nitrogen sources, linear correlations were lost and aroma production became unpredictable. However, even in complex medium minor changes in amino acid concentration continued to directly impact the formation of aromatic compounds, suggesting that the relative concentration of individual amino acids remains a predictor of aromatic outputs, independently of the complexity of metabolic interactions between carbon and nitrogen metabolism and between amino acid degradation and utilization pathways.

  13. Release of nitrogen compounds to the extracellular medium by three strains of Saccharomyces cerevisiae during induced autolysis in a model wine system.

    PubMed

    Martínez-Rodriguez, A J; Carrascosa, A V; Polo, M C

    2001-08-15

    To detect differences among three strains of Saccharomyces cerevisiae used in the manufacture of sparkling wines and to study the changes in nitrogen compounds during autolysis, a model wine system was used. Significant differences were observed between the mean values of the autolytic capacity of the three strains. The amount of nitrogen (total, protein, peptide and amino) present in the autolysates and the concentration of most free amino acids was significantly affected by the strain. These findings suggest that the strain of yeast used in the manufacture of sparkling wines can play an important role in the aging process and can affect final composition.

  14. Gaseous byproducts from high-temperature thermal conversion elemental analysis of nitrogen- and sulfur-bearing compounds with considerations for δ2H and δ18O analyses.

    PubMed

    Hunsinger, Glendon B; Tipple, Christopher A; Stern, Libby A

    2013-07-30

    High-temperature, conversion-reduction (HTC) systems convert hydrogen and oxygen in materials into H2 and CO for δ(2)H and δ(18)O measurements by isotope ratio mass spectrometry. HTC of nitrogen- and sulfur-bearing materials produces unintended byproduct gases that could affect isotope analyses by: (1) allowing isotope exchange reactions downstream of the HTC reactor, (2) creating isobaric or co-elution interferences, and (3) causing deterioration of the chromatography. This study characterizes these HTC byproducts. A HTC system (ThermoFinnigan TC/EA) was directly connected to a gas chromatograph/quadrupole mass spectrometer in scan mode (m/z 8 to 88) to identify the volatile products generated by HTC at conversion temperatures of 1350 °C and 1450 °C for a range of nitrogen- and sulfur-bearing solids [keratin powder, horse hair, caffeine, ammonium nitrate, potassium nitrate, ammonium sulfate, urea, and three nitrated organic explosives (PETN, RDX, and TNT)]. The prominent HTC byproduct gases include carbon dioxide, hydrogen cyanide, methane, acetylene, and water for all nitrogen-bearing compounds, as well as carbon disulfide, carbonyl sulfide, and hydrogen sulfide for sulfur-bearing compounds. The 1450 °C reactor temperature reduced the abundance of most byproduct gases, but increased the significant byproduct, hydrogen cyanide. Inclusion of a post-reactor chemical trap containing Ascarite II and Sicapent, in series, eliminated the majority of byproducts. This study identified numerous gaseous HTC byproducts. The potential adverse effects of these gases on isotope ratio analyses are unknown but may be mitigated by higher HTC reactor temperatures and purifying the products with a purge-and-trap system or with chemical traps. Published in 2013. This article is a U.S. Government work and is in the public domain in the USA.

  15. AIRBORNE REDUCED NITROGEN: AMMONIA EMISSIONS FROM AGRICULTURE AND OTHER SOURCES. (R826371C006)

    EPA Science Inventory

    Ammonia is a basic gas and one of the most abundant nitrogen-containing compounds in the atmosphere. When emitted, ammonia reacts with oxides of nitrogen and sulfur to form particles, typically in the fine particle size range. Roughly half of the PM2.5 mass in easte...

  16. 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. © 2013 Blackwell Publishing Ltd.

  17. Development of airborne eddy-correlation flux measurement capabilities for reactive oxides of nitrogen

    NASA Technical Reports Server (NTRS)

    Bradshaw, John (Principal Investigator); Zheng, Xiaonan; Sandholm, Scott T.

    1996-01-01

    This research is aimed at producing a fundamental new research tool for characterizing the source strength of the most important compound controlling the hemispheric and global scale distribution of tropospheric ozone. Specifically, this effort seeks to demonstrate the proof-of-concept of a new general purpose laser-induced fluorescence based spectrometer for making airborne eddy-correlation flux measurements of nitric oxide (NO) and other reactive nitrogen compounds. The new all solid-state laser technology being used in this advanced sensor will produce a forerunner of the type of sensor technology that should eventually result in highly compact operational systems. The proof-of-concept sensor being developed will have over two orders-of-magnitude greater sensitivity than present-day instruments. In addition, this sensor will offer the possibility of eventual extension to airborne eddy-correlation flux measurements of nitrogen dioxide (NO2) and possibly other compounds, such as ammonia (NH3), peroxyradicals (HO2), nitrateradicals (NO3) and several iodine compounds (e.g., I and IO). Demonstration of the new sensor's ability to measure NO fluxes will occur through a series of laboratory and field tests. This proof-of-concept demonstration will show that not only can airborne fluxes of important ultra-trace compounds be made at the few parts-per-trillion level, but that the high accuracy/precision measurements currently needed for predictive models can also. These measurement capabilities will greatly enhance our current ability to quantify the fluxes of reactive nitrogen into the troposphere and significantly impact upon the accuracy of predictive capabilities to model O3's distribution within the remote troposphere. This development effort also offers a timely approach for producing the reactive nitrogen flux measurement capabilities that will be needed by future research programs such as NASA's planned 1999 Amazon Biogeochemistry and Atmospheric Chemistry Experimental portion of LBA.

  18. Nitrogen uptake by wheat seedlings, interactive effects of four nitrogen sources: NO3-, NO2-, NH4+, and urea

    NASA Technical Reports Server (NTRS)

    Criddle, R. S.; Ward, M. R.; Huffaker, R. C.

    1988-01-01

    The net influx (uptake) rates of NO3-, NH4+, NO2-, and urea into roots of wheat (Triticum aestivum cv Yecora Rojo) seedlings from complete nutrient solutions containing all four compounds were monitored simultaneously. Although urea uptake was too slow to monitor, its presence had major inhibitory effects on the uptake of each of the other compounds. Rates of NO3-, NH4+, and NO2- uptake depended in a complex fashion on the concentration of all four N compounds. Equations were developed which describe the uptake rates of each of the compounds, and of total N, as functions of concentrations of all N sources. Contour plots of the results show the interactions over the range of concentrations employed. The coefficients of these equations provide quantitative values for evaluating primary and interactive effects of each compound on N uptake.

  19. Solar nebula chemistry - Implications for volatiles in the solar system

    NASA Technical Reports Server (NTRS)

    Fegley, Bruce, Jr.; Prinn, Ronald G.

    1989-01-01

    Current theoretical models of solar nebula chemistry which take into account the interplay between chemistry and dynamics are presented for the abundant reactive volatile elements including hydrogen, carbon, nitrogen, oxygen, and sulfur. Results of these models indicate that, in the solar nebula, the dominant carbon and nitrogen gases were CO and NO, whereas, in giant planet subnebulae, the dominant carbon and nitrogen gases were CH4 and NH3; in the solar nebula, the Fe metal grains catalyzed the formation of organic compounds from CO and H2 via the Fischer-Tropsch-type reaction. It was also found that, in solar nebula, bulk FeS formation was kinetically favorable, while FeO incorporation into silicates and bulk Fe3O4 formation were kinetically inhibited. Furthermore, clathrate formation was kinetically inhibited in the solar nebula, while it was kinetically favorable in giant planet subnebulae.

  20. Initial nitrogen enrichment conditions determines variations in nitrogen substrate utilization by heterotrophic bacterial isolates.

    PubMed

    Ghosh, Suchismita; Ayayee, Paul A; Valverde-Barrantes, Oscar J; Blackwood, Christopher B; Royer, Todd V; Leff, Laura G

    2017-04-04

    The nitrogen (N) cycle consists of complex microbe-mediated transformations driven by a variety of factors, including diversity and concentrations of N compounds. In this study, we examined taxonomic diversity and N substrate utilization by heterotrophic bacteria isolated from streams under complex and simple N-enrichment conditions. Diversity estimates differed among isolates from the enrichments, but no significant composition were detected. Substrate utilization and substrate range of bacterial assemblages differed within and among enrichments types, and not simply between simple and complex N-enrichments. N substrate use patterns differed between isolates from some complex and simple N-enrichments while others were unexpectedly similar. Taxonomic composition of isolates did not differ among enrichments and was unrelated to N use suggesting strong functional redundancy. Ultimately, our results imply that the available N pool influences physiology and selects for bacteria with various abilities that are unrelated to their taxonomic affiliation.

  1. Synthesis of carbon-11, fluorine-18, and nitrogen-13 labeled radiotracers for biomedical applications

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Fowler, J.S.; Wolf, A.P.

    A number of reviews, many of them recent, have appeared on various aspects of /sup 11/C, /sup 18/F and /sup 13/N-labeled radiotracers. This monograph treats the topic principally from the standpoint of synthetic organic chemistry while keeping in perspective the necessity of integrating the organic chemistry with the design and ultimate application of the radiotracer. Where possible, recent examples from the literature of organic synthesis are introduced to suggest potentially new routes which may be applied to problems in labeling organic molecules with the short-lived positron emitters, carbon-11, fluorine-18, and nitrogen-13. The literature survey of carbon-11, fluorine-18 and nitrogen-13 labeledmore » compounds presented are of particular value to scientists working in this field. Two appendices are also included to provide supplementary general references. A subject index concludes this volume.« less

  2. Characterization of bio-oil from induction-heating pyrolysis of food-processing sewage sludges using chromatographic analysis.

    PubMed

    Tsai, Wen-Tien; Lee, Mei-Kuei; Chang, Jeng-Hung; Su, Ting-Yi; Chang, Yuan-Ming

    2009-05-01

    In this study, gas chromatography-mass spectrometry (GC-MS) was used to analyze the pyrolytic bio-oils and gas fractions derived from the pyrolysis of industrial sewage sludges using induction-heating technique. The liquid products were obtained from the cryogenic condensation of the devolatilization fraction in a nitrogen atmosphere using a heating rate of 300 degrees C/min ranging from 25 to 500 degrees C. The analytical results showed that the pyrolysis bio-oils were very complex mixtures of organic compounds and contained a lot of nitrogenated and/or oxygenated compounds such as aliphatic hydrocarbons, phenols, pyridines, pyrroles, amines, ketones, and so on. These organic hydrocarbons containing nitrogen and/or oxygen should originate from the protein and nucleic acid textures of the microbial organisms present in the sewage sludge. The non-condensable devolatilization fractions were also composed of nitrogenated and oxygenated compounds, but contained small fractions of phenols, 1H-indoles, and fatty carboxylic acids. On the other hand, the compositions in the non-condensable gas products were principally carbon dioxide, carbon monoxide and methane analyzed by gas chromatography-thermal conductivity detector (GC-TCD).

  3. Study on pyrolysis characteristics of lignocellulosic biomass impregnated with ammonia source.

    PubMed

    Li, Kai; Zhu, Changpeng; Zhang, Liqiang; Zhu, Xifeng

    2016-06-01

    The current study presents the pyrolysis characteristics of rice husk impregnated with different kinds of ammonia source (ammonium acetate, urea, ammonium sulfate and ammonium dihydrogen phosphate) in a fixed bed reactor. The introduction of ammonia source in pyrolysis process achieved the conversation from carbonyl compounds to nitrogenous heterocyclic compounds. The liquid product of urea-impregnated biomass has higher content of nitrogenous heterocyclic compounds (8.35%) and phenols (30.4%). For ammonium sulfate and ammonium dihydrogen phosphate-impregnated biomass, the quantity of compounds in liquid products reduces remarkably, and the gas products are rich in CO and H2. All the solid products of pyrolysis have great potential application in biochar-based fertilizer and activated carbon for their high N content. Copyright © 2016 Elsevier Ltd. All rights reserved.

  4. Effect of additives in the shelflife extension of chilled and frozen stored Indian octopus (Cistopus indicus).

    PubMed

    Manimaran, Uthaman; Shakila, Robinson Jeya; Shalini, Rajendran; Sivaraman, Balasubramanian; Sumathi, Ganesan; Selvaganapathi, Rajendran; Jeyasekaran, Geevarathnam

    2016-02-01

    In this study, the effect of commercial additives viz. cafodos and altesa employed to treat Indian octopus (Cistopus indicus) was examined during chilled and frozen storage. Shelf lives of treated and untreated octopus in ice were 6 and 8 days, respectively in ice. Treated and untreated frozen octopus had a shelf life of 40 days. Autolytic and microbiological changes were not controlled by the additives, as evidenced through rapid reduction in non-protein nitrogen (NPN) and α-amino nitrogen (α-AN) compounds; as well as accumulation of water soluble ammoniacal nitrogen and total volatile base- nitrogen (TVB-N) compounds. Loss of texture and colour were the major quality defects noticed in treated octopus as a result of enhanced protein solubility. Therefore, the additives approved for use in octopus neither enhanced the shelf life nor improved the sensory quality.

  5. Distribution and variability of nitrogen and phosphorus in the alluvial, High Plains, Rush Springs, and Blaine aquifers in western Oklahoma

    USGS Publications Warehouse

    Becker, C.J.

    1994-01-01

    Aquifers are the primary source of water for drinking and agricultural purposes in western Oklahoma. Health concerns about consuming nitrogen and an increased reliance on ground water for drinking necessitate a better understanding of the cause and effect of contamination from nutrients. The purpose of this project was to compile nutrients data from the National Water Information System data base for the alluvial aquifers west of longitude 98 degrees W. and from three bedrock aquifers, High Plains, Rush Springs, and Blaine, and provide this information in a report for future projects and for the facilitation of nutrient source management. The scope of the work consisted of (1) compiling ground-water quality data concerning nitrogen and phosphorus ions, (2) constructing boxplots illustrating data variability, (3) maps for each aquifer showing locations of wells when nitrogen and phosphorus ions were measured in ground water and where concentrations of nitrate and nitrite, reported as nitrogen, exceed the maximum contaminant level, and (4) calculating summary statistics. Nutrient data were obtained from the U.S. Geological Survey data base called the National Water Information System. Data were restricted to ground-water samples, but no restrictions were placed on well and water use or date and time of sampling. Compiled nutrient data consist of dissolved and total concentrations of the common nitrogen and phosphorus ions measured in ground water. For nitrogen these ions include nitrate, nitrite, ammonium, and nitrite plus nitrate. All concentrations are reported in milligrams per liter as nitrogen. Phosphorus in ground water is measured as the orthophosphate ion, and is reported in milligrams per liter as phosphorus. Nutrient variability is illustrated by a standard boxplot. The data are presented by aquifer or hydrologic subregion for alluvial aquifers, with one boxplot constructed for each nutrient compound if more than four analyses are present. Maps for each aquifer show where nitrogen and phosphorus have been measured in ground water and where the concentrations of nitrate and nitrite exceed the maximum contaminant level. A statistical summary for each aquifer and subregion show if censored data were present, number of samples in each data set, largest minimum reporting level for each nutrient compound, percentiles used to construct boxplots, and minimum and maximum values. Also given are the number of wells sampled in each aquifer and the number of wells exceeding the maximum contaminant level.

  6. 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.

  7. Mid-Infrared Spectroscopy of Polycyclic Aromatic Nitrogen Heterocycles (PANHS) and their Ions

    NASA Technical Reports Server (NTRS)

    Mattioda, Andrew L.; Hudgin, Douglas; Bauschlicher, Charles W.; Alamandola, Louis J.

    2003-01-01

    In recent years, polycyclic aromatic nitrogen heterocycles (PANHs) have attracted a good deal of attention because of their potent carcinogenic and mutagenic properties, and their prevalence in our environment. Such species also play a prominent role in the chemistry of life up to and including the very nucleobases from which our DNA is constructed. Surprisingly, these compounds may even be common outside of our terrestrial environment. To wit, it is now widely accepted that polycyclic aromatic materials are abundant in space and represent a major reservoir of organic carbon in the interstellar medium and developing planetary systems. Given that nitrogen is the fourth most abundant chemically reactive element in space (surpassed only by hydrogen, carbon, and oxygen), it is entirely reasonable to suspect that PANHs may represent an important component of that organic reservoir. Motivated by their intrinsic merit and with special attention toward evaluating their exobiological significance, we have initiated a program to study the spectroscopic and chemical properties of P A " s under conditions relevant to extraterrestrial environments. Here we present the first results of that program-infrared spectroscopic measurements on a series of PANH"s in neutral and cationic forms, isolated in inert matrices at cryogenic temperatures.temperatures. The species studied include: 1 -, and 2-azabenz[a]anthracene, 1-, 2-, and 4- azachrysene, dibenz[a,h]acridine, and dibenz[a,J)acridine. The experimental measurements are also compared with theoretical spectra calculated using density functional theory. General spectroscopic trends observed in this series of compounds are discussed and the implications of these results for Astrophysics and Exobiology are considered.

  8. Relationships between Molecular Composition and Optical Properties of Dissolved Organic Matter

    NASA Astrophysics Data System (ADS)

    Cooper, W. T.; Tfaily, M.; Osborne, D.; Paul, A.; Podgorski, D. C.; Corbett, J.; Chanton, J.

    2009-12-01

    Our focus is on the relationships between the optical properties of dissolved organic matter (DOM) and its molecular composition. For example, we demonstrated that changes in the absorption and fluorescence characteristics of DOM in outwelling from Brazilian mangrove forests correlated with decreases in highly unsaturated organic compounds as DOM was transported from mangrove porewaters to the continental shelf. In that work we combined ultrahigh resolution Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS) that provided detailed compositional information with absorption and Excitation/Emission Matrix (EEM) spectroscopy This presentation will highlight new results utilizing the combination of optical spectroscopy and FT-ICR mass spectrometry to illuminate the processes which control DOM cycling. Our focus will be on the contributions of the heteroatom components of DOM (i.e. organic sulfur and organic nitrogen) to its optical properties and how changes in optical properties correlate with important environmental processes like humification and bioavailability. Figure 1 below includes a narrow 0.20 Dalton window from a mass spectrum which demonstrates the ability of ultrahigh resolution mass spectrometry to resolve and identify nitrogen heteroatom compounds in DOM. Our study sites include the Glacial Lake Agassiz Peatlands (GLAP) in northern Minnesota and wetlands in the Caloosahatchee River basin in South Florida. Figure 1. Isolated 0.20 Da window of an ESI-FT-ICR mass spectrum of DOM from a GLAP bog. Labels identify N1 (d,e,f) and N3 classes of nitrogen heteroatoms. The 0.0031 Da mass spacing is used to confirm the N3 class.

  9. Explosive Ordnance Disposal Proficiency Range and Multi-Purpose Contingency Training Area

    DTIC Science & Technology

    2007-04-01

    1,3,5-trimethylene-2,4,6-trinitramine (RDX), cyclo-1,3,5,7- tetramethylene-2,4,6,8-tetra-nitramine [HMX], tetryl, and picric acid ; inorganic compounds...nitrogen oxides, which cause acid rain. Ir. addition, nitrogen oxide emissions contribute to the problem of global warming and also r;ombine with...of sUlfur oxide and nitrogen oxides, which cause acid ram. Ji:, addition, nitrogen oxide emis~ions contribute to the probl!llll of global warming

  10. Effects of low nitrogen supply on tomato (Solanum lycopersicum) fruit yield and quality with special emphasis on sugars, acids, ascorbate, carotenoids, and phenolic compounds.

    PubMed

    Bénard, Camille; Gautier, Hélène; Bourgaud, Frédéric; Grasselly, Dominique; Navez, Brigitte; Caris-Veyrat, Catherine; Weiss, Marie; Génard, Michel

    2009-05-27

    The objective of this study was to determine the impact of lowering nitrogen supply from 12 to 6 or 4 mM NO(3)(-) on tomato fruit yield and quality during the growing season. Lowering nitrogen supply had a low impact on fruit commercial yield (-7.5%), but it reduced plant vegetative growth and increased fruit dry matter content, improving consequently fruit quality. Fruit quality was improved due to lower acid (10-16%) and increased soluble sugar content (5-17%). The content of some phenolic compounds (rutin, a caffeic acid glycoside, and a caffeic acid derivate) and total ascorbic acid tended to be higher in fruit with the lowest nitrogen supply, but differences were significant in only a few cases (trusses). With regard to carotenoids, data did not show significant and univocal differences related to different levels of nitrogen supply. Thus, reducing nitrogen fertilization limited environmental pollution, on the one hand, and may improve, on the other hand, both growers' profits, by limiting nitrogen inputs, and fruit quality for consumers, by increasing tomato sugars content. It was concluded that primary and secondary metabolites could be affected as a result of a specific response to low nitrogen, combined with a lower degree of vegetative development, increasing fruit irradiance, and therefore modifying fruit composition.

  11. 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. Published by Elsevier B.V.

  12. Pharmaceuticals and Related Drugs.

    ERIC Educational Resources Information Center

    Gilpin, R. K.; Pachla, L. A.

    1989-01-01

    This review is divided into these topics: alkaloids, antibiotics, inorganics, nitrogen and oxygen containing compounds, steroids, sulfur containing compounds, vitamins, techniques, and miscellaneous methods. The review covers from November 1986, to October 1988. (MVL)

  13. Sources and behaviour of nitrogen compounds in the shallow groundwater of agricultural areas (Poyang Lake basin, China).

    PubMed

    Soldatova, Evgeniya; Guseva, Natalia; Sun, Zhanxue; Bychinsky, Valeriy; Boeckx, Pascal; Gao, Bai

    2017-07-01

    Nitrogen contamination of natural water is a typical problem for various territories throughout the world. One of the regions exposed to nitrogen pollution is located in the Poyang Lake basin. As a result of agricultural activity and dense population, the shallow groundwater of this area is characterised by a high concentration of nitrogen compounds, primarily NO 3 - , with the concentration varying from 0.1mg/L to 206mg/L. Locally, high ammonium content occurs in the shallow groundwater with low reduction potential Eh (<100mV). However, in general, the shallow groundwater of the Poyang Lake basin has Eh>100mV. To identify sources of nitrogen species and the factors that determine their behaviour, the dual stable isotope approach (δ 15 N and δ 18 О) and physical-chemical modelling were applied. Actual data were collected by sampling shallow groundwater from domestic water supply wells around the lake. The δ 18 О values from -4.1‰ to 13.9‰ with an average value of 5.3 permille indicate a significant influence of nitrification on nitrogen balance. The enrichment of nitrate with the 15 N isotope indicates that manure and domestic sewage are the principal sources of nitrogen compounds. Inorganic nitrogen speciation and thermodynamic calculations demonstrate the high stability of nitrate in the studied groundwater. Computer simulation and field observations indicate the reducing conditions formed under joint effects of anthropogenic factors and appropriate natural conditions, such as the low-level topography in which decreased water exchange rate can occur. The simulation also demonstrates the growth in pH of the groundwater as a consequence of fertilisation, which, in turn, conduced to the clay mineral formation at lower concentrations of aqueous clay-forming components than the ones under the natural conditions. Copyright © 2017 Elsevier B.V. All rights reserved.

  14. The transformation of nitrogen during pressurized entrained-flow pyrolysis of Chlorella vulgaris.

    PubMed

    Maliutina, Kristina; Tahmasebi, Arash; Yu, Jianglong

    2018-08-01

    The transformation of nitrogen in microalgae during entrained-flow pyrolysis of Chlorella vulgaris was systematically investigated at the temperatures of 600-900 °C and pressures of 0.1-4.0 MPa. It was found that pressure had a profound impact on the transformation of nitrogen during pyrolysis. The nitrogen retention in bio-char and its content in bio-oil reached a maximum value at 1.0 MPa. The highest conversion of nitrogen (50.25 wt%) into bio-oil was achieved at 1.0 MPa and 800 °C, which was about 7 wt% higher than that at atmospheric pressure. Higher pressures promoted the formation of pyrrolic-N (N-5) and quaternary-N (N-Q) compounds in bio-oil at the expense of nitrile-N and pyridinic-N (N-6) compounds. The X-Ray photoelectron spectroscopy (XPS) and Fourier transform infrared spectroscopy (FTIR) results on bio-chars clearly evidenced the transformation of N-5 structures into N-6 and N-Q structures at elevated pressures. The nitrogen transformation pathways during pyrolysis of microalgae were proposed and discussed. Copyright © 2018 Elsevier Ltd. All rights reserved.

  15. Amino acid compositions in heated carbonaceous chondrites and their compound-specific nitrogen isotopic ratios

    NASA Astrophysics Data System (ADS)

    Chan, Queenie Hoi Shan; Chikaraishi, Yoshito; Takano, Yoshinori; Ogawa, Nanako O.; Ohkouchi, Naohiko

    2016-01-01

    A novel method has been developed for compound-specific nitrogen isotope compositions with an achiral column which was previously shown to offer high precision for nitrogen isotopic analysis. We applied the method to determine the amino acid contents and stable nitrogen isotopic compositions of individual amino acids from the thermally metamorphosed (above 500 °C) Antarctic carbonaceous chondrites Ivuna-like (CI)1 (or CI-like) Yamato (Y) 980115 and Ornans-like (CO)3.5 Allan Hills (ALH) A77003 with the use of gas chromatography/combustion/isotope ratio mass spectrometry. ALHA77003 was deprived of amino acids due to its extended thermal alteration history. Amino acids were unambiguously identified in Y-980115, and the δ15N values of selected amino acids (glycine +144.8 ‰; α-alanine +121.2 ‰) are clearly extraterrestrial. Y-980115 has experienced an extended period of aqueous alteration as indicated by the presence of hydrous mineral phases. It has also been exposed to at least one post-hydration short-lived thermal metamorphism. Glycine and alanine were possibly produced shortly after the accretion event of the asteroid parent body during the course of an extensive aqueous alteration event and have abstained from the short-term post-aqueous alteration heating due to the heterogeneity of the parent body composition and porosity. These carbonaceous chondrite samples are good analogs that offer important insights into the target asteroid Ryugu of the Hayabusa-2 mission, which is a C-type asteroid likely composed of heterogeneous materials including hydrated and dehydrated minerals.

  16. 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. Copyright © 2013 Elsevier Ltd. All rights reserved.

  17. X-ray photoelectron spectroscopic study of sulfur-nitrogen-fluorine compounds

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Beach, D.B.; Jolly, W.L.; Mews, R.

    1984-11-21

    The gas-phase core binding energies of NSF, NSF/sub 3/, and several compounds of the types NSF/sub 2/R and F/sub 2/SNR have been determined. Qualitative interpretation of the data shows that N(p..pi..) ..-->.. S(d..pi..) bonding is probably important in the NSF/sub 2/R compounds and in NSF/sub 3/, that the bonding of the sulfur atom in NSF is similar to that in SO/sub 2/, and that the nitrogen atom of NSF/sub 3/ is more negatively charged than that of NSF (in spite of a stronger N-S bond in NSF/sub 3/). Quantitative interpretation of the data for NSF and NSF/sub 3/, together withmore » literature valence ionization potentials, shows that the HOMO of each molecule has principally nitrogen 2p character and is stabilized by interaction with a higher lying sulfur 3d orbital. The approximate atomic orbital contributions to the other molecuar orbitals of these molecules are deduced.« less

  18. Compound-Specific δ¹⁵N and δ¹³C Analyses of Amino Acids for Potential Discrimination between Organically and Conventionally Grown Wheat.

    PubMed

    Paolini, Mauro; Ziller, Luca; Laursen, Kristian Holst; Husted, Søren; Camin, Federica

    2015-07-01

    We present a study deploying compound-specific nitrogen and carbon isotope analysis of amino acids to discriminate between organically and conventionally grown plants. We focused on grain samples of common wheat and durum wheat grown using synthetic nitrogen fertilizers, animal manures, or green manures from nitrogen-fixing legumes. The measurement of amino acid δ(15)N and δ(13)C values, after protein hydrolysis and derivatization, was carried out using gas chromatography-combustion-isotope ratio mass spectrometry (GC-C-IRMS). Our results demonstrated that δ(13)C of glutamic acid and glutamine in particular, but also the combination of δ(15)N and δ(13)C of 10 amino acids, can improve the discrimination between conventional and organic wheat compared to stable isotope bulk tissue analysis. We concluded that compound-specific stable isotope analysis of amino acids represents a novel analytical tool with the potential to support and improve the certification and control procedures in the organic sector.

  19. On the Extraction of Aromatic Compounds from Hydrocarbons by Imidazolium Ionic Liquids

    PubMed Central

    Cassol, Cláudia C.; Umpierre, Alexandre P.; Ebeling, Günter; Ferrera, Bauer; Chiaro, Sandra S. X.; Dupont, Jairton

    2007-01-01

    The liquid-liquid equilibrium for the ternary system formed by n-octane and aromatic (alkylbenzenes) and heteroaromatic compounds (nitrogen and sulfur containing heterocyles) and 1-alkyl-3-methylimidazolium ionic liquids (ILs) associated with various anions has been investigated. The selectivity on the extraction of a specific aromatic compound is influenced by anion volume, hydrogen bond strength between the anion and the imidazolium cation and the length of the 1-methyl-3-alkylimidazolium alkyl side chain. The interaction of alkylbenzenes and sulfur heterocyles with the IL is preferentially through CH-π hydrogen bonds and the quantity of these aromatics in the IL phase decreases with the increase of the steric hindrance imposed by the substituents on the aromatic nucleus. In the case of nitrogen heterocycles the interaction occurs preferentially through N(heteroaromatic)-H(imidazolium) hydrogen bonds and the extraction process is largely controlled by the nitrogen heterocycle pKa. Competitive extraction experiments suggest that benzene, pyridine and dibenzothiophene do not compete for the same hydrogen bond sites of the IL.

  20. Effect of Nitrogen Compounds on Shrimp Litopenaeus vannamei: Histological Alterations of the Antennal Gland.

    PubMed

    Fregoso-López, Marcela G; Morales-Covarrubias, María S; Franco-Nava, Miguel A; Ponce-Palafox, Jesús T; Fierro-Sañudo, Juan F; Ramírez-Rochín, Javier; Páez-Osuna, Federico

    2018-06-01

    Two experimental modules with different stocking densities (M1 = 70 and M2 = 120 shrimp m -2 ) were examined weekly during 72-day culture cycle at low-salinity water (1.9 g L -1 ) and zero-water exchange to examine the effects of water quality deterioration on the antennal gland (AG) of shrimp. Results showed survival rates of 87.7% and 11.9% in M1 and M2, respectively. Water temperature, pH, dissolved oxygen, and chlorophyll a were not significantly different between modules but the concentrations of the nitrogen compounds were significantly different between modules with the exception of nitrite-N, showing a higher histological alteration index in M2 (32 ± 10) than M1 (22 ± 0) with a strong correlation with the nitrogen compounds. During the last weeks was evidenced in M1 inflammation and hemocytic and hemolymph infiltration, while in M2, melanization, hemocytic melanized nodules and cells with kariorrexis.

  1. Nitrogen sources affect productivity, desiccation tolerance and storage stability of Beauveria bassiana blastospores.

    PubMed

    Mascarin, G M; Kobori, N N; Jackson, M A; Dunlap, C A; Delalibera, Í

    2018-03-01

    Nitrogen is a critical element in industrial fermentation media. This study investigated the influence of various nitrogen sources on blastospore production, desiccation tolerance and storage stability using two strains of the cosmopolitan insect-pathogenic fungus Beauveria bassiana. Complex organic sources of nitrogen such as soy flour, autolysed yeast and cottonseed flour induced great numbers of blastospores after 2-3 days of fermentation, which also survived drying and remained viable (32-56% survival) after 9 months storage at 4°C, although variations were found between strains. Nitrogen availability in the form of free amino acids directly influenced blastospore production and resistance to desiccation. Increasing glucose and nitrogen concentrations up to 120 and 30 g l -1 , respectively, did not improve blastospore production but enhanced desiccation tolerance. Cell viability after drying and upon fast-rehydration was increased when ≥25 g acid-hydrolysed casein per litre was supplemented in the liquid culture medium. These findings indicate that low-cost complex nitrogen compounds are suitable to enhance yeast-like growth by B. bassiana with good desiccation tolerance and therefore support its further scale-up production as a mycoinsecticide. Nitrogen is the most expensive nutrient in liquid media composition, but this study underscores the feasibility of using low-cost nitrogen compounds composed mainly of agro-industrial by-products for rapid production of desiccation-tolerant B. bassiana blastospores by liquid culture fermentation. © 2018 The Society for Applied Microbiology.

  2. 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.

  3. Utilization of the terrestrial cyanobacteria

    NASA Astrophysics Data System (ADS)

    Katoh, Hiroshi; Tomita-Yokotani, Kaori; Furukawa, Jun; Kimura, Shunta; Yokoshima, Mika; Yamaguchi, Yuji; Takenaka, Hiroyuki

    The terrestrial, N _{2}-fixing cyanobacterium, Nostoc commune has expected to utilize for agriculture, food and terraforming cause of its extracellular polysaccharide, desiccation tolerance and nitrogen fixation. Previously, the first author indicated that desiccation related genes were analyzed and the suggested that the genes were related to nitrogen fixation and metabolisms. In this report, we suggest possibility of agriculture, using the cyanobacterium. Further, we also found radioactive compounds accumulated N. commune (cyanobacterium) in Fukushima, Japan after nuclear accident. Thus, it is investigated to decontaminate radioactive compounds from the surface soil by the cyanobacterium and showed to accumulate radioactive compounds using the cyanobacterium. We will discuss utilization of terrestrial cyanobacteria under closed environment. Keyword: Desiccation, terrestrial cyanobacteria, bioremediation, agriculture

  4. Hydroxymethyl phosphine compounds for use as diagnostic and therapeutic pharmaceuticals and method of making same

    DOEpatents

    Katti, Kattesh V.; Karra, Srinivasa Rao; Berning, Douglas E.; Smith, C. Jeffrey; Volkert, Wynn A.; Ketring, Alan R.

    1999-01-01

    A compound and method of making a compound for use as a diagnostic or therapeutic pharmaceutical comprises at least one functionalized hydroxyalkyl phosphine donor group and one or more sulfur or nitrogen donor and a metal combined with the ligand.

  5. Hydroxymethyl phosphine compounds for use as diagnostic and therapeutic pharmaceuticals and method of making same

    DOEpatents

    Katti, Kattesh V.; Karra, Srinivasa Rao; Berning, Douglas E.; Smith, C. Jeffrey; Volkert, Wynn A.; Ketring, Alan R.

    2000-01-01

    A compound and method of making a compound for use as a diagnostic or therapeutic pharmaceutical comprises at least one functionalized hydroxyalkyl phosphine donor group and one or more sulfur or nitrogen donor and a metal combined with the ligand.

  6. Nitrogenase Reduction of Carbon-Containing Compounds

    PubMed Central

    Seefeldt, Lance C.; Yang, Zhi-Yong; Duval, Simon; Dean, Dennis R.

    2013-01-01

    Nitrogenase is an enzyme found in many bacteria and archaea that catalyzes biological dinitrogen fixation, the reduction of N2 to NH3, accounting for the major input of fixed nitrogen into the biogeochemical N cycle. In addition to reducing N2 and protons, nitrogenase can reduce a number of small, non-physiological substrates. Among these alternative substrates are included a wide array of carbon containing compounds. These compounds have provided unique insights into aspects of the nitrogenase mechanism. Recently, it was shown that carbon monoxide (CO) and carbon dioxide (CO2) can also be reduced by nitrogenase to yield hydrocarbons, opening new insights into the mechanism of small molecule activation and reduction by this complex enzyme as well as providing clues for the design of novel molecular catalysts. PMID:23597875

  7. 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

  8. 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.

  9. 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

  10. 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.

  11. Variations in the Peak Position of the 6.2 micron Interstellar Emission Feature: A Tracer of N in the Interstellar Polycyclic Aromatic Hydrocarbon Population

    NASA Technical Reports Server (NTRS)

    Hudgins, Douglas M.; Bauschlicher, Charles W.; Allamandola, L. J.

    2005-01-01

    This paper presents the results of an investigation of the molecular characteristics that underlie the observed peak position and profile of the nominal 6.2 micron interstellar emission band generally attributed to the CC stretching vibrations of polycyclic aromatic hydrocarbons (PAHs). It begins with a summary of recent experimental and theoretical studies ofthe spectroscopic properties of large (>30 carbon atoms) PAH cations as they relate to this aspect of the astrophysical problem. It then continues with an examination of the spectroscopic properties of a number of PAH variants within the context of the interstellar 6.2 micron emission, beginning with a class of compounds known as polycyclic aromatic nitrogen heterocycles (PANHs; PAHs with one or more nitrogen atoms substituted into their carbon skeleton). In this regard, we summarize the results of recent relevant experimental studies involving a limited set of small PANHs and their cations and then report the results of a comprehensive computational study that extends that work to larger PANH cations including many nitrogen-substituted variants of coronene(+) (C24H12(+)), ovalene(+) (C32H14(+)), circumcoronene(+) (C54H18(+)), and circum-circumcoronene(+) (C96H24(+)). Finally, we report the results of more focused computational studies of selected representatives from a number of other classes of PAH variants that share one or more of the key attributes of the PANH species studied. These alternative classes of PAH variants include (1) oxygen- and silicon-substituted PAH cations; (2) PAH-metal ion complexes (metallocenes) involving the cosmically abundant elements magnesium and iron; and (3) large, asymmetric PAH cations. Overall, the studies reported here demonstrate that increasing PAH size alone is insuEcient to account for the position of the shortest wavelength interstellar 6.2 micron emission bands, as had been suggested by earlier studies. On the other hand, this work reveals that substitution of one or more nitrogen atoms within the interior of the carbon skeleton of a PAH cation induces a significant blueshift in the position of the dominant CC stretching feature of these compounds that is suf6cient to account for the position of the interstellar bands. Subsequent studies of the effects of substitution by other heteroatoms (O and Si), metal ion complexation (Fe(+), Mg(+), and Mg(2+)), and molecular symmetry variation-all of which fail to reproduce the blueshift observed in the PANH cations-indicate that N appears to be unique in its ability to accommodate the position of the interstellar 6.2 micron bands while simultaneously satisfying the other constraints of the astrophysical problem. This result implies that the peak position of the interstellar feature near 6.2 micron traces the degree of nitrogen substitution in the population, that most of the PAHs responsible for the interstellar IR emission features incorporate nitrogen within their aromatic networks, and that a lower limit of 1%-2% of the cosmic nitrogen is sequestered within the interstellar PAH population. Finally, in view of the ubiquity and abundance of interstellar PAHs and the permanent dipoles and distinctive electronic structures of these nitrogen-substituted variants, this work impacts a wide range of observational phenomena outside of the infrared region of the spectrum including the forest of unidentified molecular rotational features and the anomalous Galactic foreground emission in the microwave, and the diffuse interstellar bands (DIBs) and other structure in the interstellar extinction curve in the ulhviolet/visible. These astrophysical ramifications are discussed, and the dipole moments and rotational constants are tabulated to facilitate further investigations of the astrophysical role of nitrogen-substituted aromatic compounds.

  12. Production of sensory compounds by means of the yeast Dekkera bruxellensis in different nitrogen sources with the prospect of producing cachaça.

    PubMed

    Castro Parente, Denise; Vidal, Esteban Espinosa; Leite, Fernanda Cristina Bezerra; de Barros Pita, Will; de Morais, Marcos Antonio

    2015-01-01

    The distilled spirit made from sugar cane juice, also known as cachaça, is a traditional Brazilian beverage that in recent years has increased its market share among international distilled beverages. Several volatile compounds produced by yeast cells during the fermentation process are responsible for the unique taste and aroma of this drink. The yeast Dekkera bruxellensis has acquired increasing importance in the fermented beverage production, as the different metabolites produced by this yeast may be either beneficial or harmful to the end-product. Since D. bruxellensis is often found in the fermentation processes carried out in ethanol fuel distillation in Brazil, we employed this yeast to analyse the physiological profile and production of aromatic compounds and to examine whether it is feasible to regard it as a cachaça-producing microorganism. The assays were performed on a small scale and simulated the conditions for the production of handmade cachaça. The results showed that the presence of aromatic and branched-chain amino acids in the medium has a strong influence on the metabolism and production of flavours by D. bruxellensis. The assimilation of these alternative nitrogen sources led to different fermentation yields and the production of flavouring compounds. The influence of the nitrogen source on the metabolism of fusel alcohols and esters in D. bruxellensis highlights the need for further studies of the nitrogen requirements to obtain the desired level of sensory compounds in the fermentation. Our results suggest that D. bruxellensis has the potential to play a role in the production of cachaça. Copyright © 2014 John Wiley & Sons, Ltd.

  13. Fungal Denitrification Activity in Vertical Flow Constructed Wetlands as Impacted by Plant Species Richness, Carbon, Nitrogen and pH Amendments.

    PubMed

    Liu, W L; Zhang, C B; Han, W J; Guan, M; Liu, S Y; Ge, Y; Chang, J

    2017-12-01

    To control potential fungal denitrification rate (PFDR) in vertical flow simulated wetlands (VFSW) microcosms, thirty VFSW microcosms were established and planted with three plant species richness levels (i.e. unplanted, monoculture, and four-species polyculture treatment), and effects of carbon, nitrogen and pH amendments on the PFDR were investigated using a room-incubating method. Among seven carbon compounds, sodium citrate, glycerol, glucose and sodium succinate were more effective in enhancing PFDRs. These enhanced effects were dependant on a given species richness level. Sodium nitrite mostly stimulated PFDRs to a greater extent than the other three nitrogen compound amendments at any richness level. Treatments with pH 5.6 or 8.4 had significantly greater PFDRs than the treatment with pH 2.8 in the three species richness levels. However, no effect of plant species richness on the PFDR was observed among any carbon, nitrogen and pH amendments. Current results suggest carbon, nitrogen and pH factors should be considered when mediating fungal denitrification in VFSW microcosms.

  14. Structure, thermodynamic and electronic properties of carbon-nitrogen cubanes and protonated polynitrogen cations

    NASA Astrophysics Data System (ADS)

    Chaban, Vitaly V.; Andreeva, Nadezhda A.

    2017-12-01

    Energy generation and storage are at the center of modern civilization. Energetic materials constitute quite a large class of compounds with a high amount of stored chemical energy that can be released. We hereby use a combination of quantum chemistry methods to investigate feasibility and properties of carbon-nitrogen cubanes and multi-charged polynitrogen cations in the context of their synthesis and application as unprecedented energetic materials. We show that the stored energy increases gradually with the nitrogen content increase. Nitrogen-poor cubanes retain their stabilities in vacuum, even at elevated temperatures. Such molecules will be probably synthesized at some point. In turn, polynitrogen cations are highly unstable, except N8H+, despite they are isoelectronic to all-carbon cubane. Kinetic stability of the cation decays drastically as its total charge increases. High-level thermodynamic calculations revealed that large amounts of energy are liberated upon decompositions of polynitrogen cations, which produce molecular nitrogen, acetylene, and protons. The present results bring a substantial insights to the design of novel high-energy compounds.

  15. Nitrogen Doped Carbon Nanotubes from Organometallic Compounds: A Review

    PubMed Central

    Nxumalo, Edward N.; Coville, Neil J.

    2010-01-01

    Nitrogen doped carbon nanotubes (N-CNTs) have become a topic of increased importance in the study of carbonaceous materials. This arises from the physical and chemical properties that are created when N is embedded in a CNT. These properties include modified chemical reactivity and modified conductivity and mechanical properties. A range of methodologies have been devised to synthesize N-CNTs. One of the procedures uses a floating catalyst in which an organometallic complex is decomposed in the gas phase in the presence of a nitrogen containing reactant to give N-CNTs. Most studies have been limited to ferrocene, ring substituted ferrocene and Fe(CO)5. This review covers the synthesis (and properties) of N-CNTs and other shaped carbon nanomaterials (SCNMs) produced using organometallic complexes. It summarizes the effects that physical parameters such as temperature, pressure, gas flow rates, type and concentration of N source etc. have on the N-CNT type, size and yields as well as the nitrogen content incorporated into the tubes that are produced from organometallic complexes. Proposed growth models for N-CNT synthesis are also reported.

  16. The carbon-nitrogen balance of the nodule and its regulation under elevated carbon dioxide concentration.

    PubMed

    Libault, Marc

    2014-01-01

    Legumes have developed a unique way to interact with bacteria: in addition to preventing infection from pathogenic bacteria like any other plant, legumes also developed a mutualistic symbiotic relationship with one gender of soil bacteria: rhizobium. This interaction leads to the development of a new root organ, the nodule, where the differentiated bacteria fix for the plant the atmospheric dinitrogen (atmN2). In exchange, the symbiont will benefit from a permanent source of carbon compounds, products of the photosynthesis. The substantial amounts of fixed carbon dioxide dedicated to the symbiont imposed to the plant a tight regulation of the nodulation process to balance carbon and nitrogen incomes and outcomes. Climate change including the increase of the concentration of the atmospheric carbon dioxide is going to modify the rates of plant photosynthesis, the balance between nitrogen and carbon, and, as a consequence, the regulatory mechanisms of the nodulation process. This review focuses on the regulatory mechanisms controlling carbon/nitrogen balances in the context of legume nodulation and discusses how the change in atmospheric carbon dioxide concentration could affect nodulation efficiency.

  17. The Carbon-Nitrogen Balance of the Nodule and Its Regulation under Elevated Carbon Dioxide Concentration

    PubMed Central

    2014-01-01

    Legumes have developed a unique way to interact with bacteria: in addition to preventing infection from pathogenic bacteria like any other plant, legumes also developed a mutualistic symbiotic relationship with one gender of soil bacteria: rhizobium. This interaction leads to the development of a new root organ, the nodule, where the differentiated bacteria fix for the plant the atmospheric dinitrogen (atmN2). In exchange, the symbiont will benefit from a permanent source of carbon compounds, products of the photosynthesis. The substantial amounts of fixed carbon dioxide dedicated to the symbiont imposed to the plant a tight regulation of the nodulation process to balance carbon and nitrogen incomes and outcomes. Climate change including the increase of the concentration of the atmospheric carbon dioxide is going to modify the rates of plant photosynthesis, the balance between nitrogen and carbon, and, as a consequence, the regulatory mechanisms of the nodulation process. This review focuses on the regulatory mechanisms controlling carbon/nitrogen balances in the context of legume nodulation and discusses how the change in atmospheric carbon dioxide concentration could affect nodulation efficiency. PMID:24987690

  18. 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...

  19. Some Experiments in Sulfur-Nitrogen Chemistry.

    ERIC Educational Resources Information Center

    Banister, Arthur J.; Smith, Nigel R. M.

    1982-01-01

    Briefly surveys the main structural types of sulfur-nitrogen compounds, and describes syntheses, suitable as undergraduate experiments, which illustrate four of the five types of cyclic species. Laboratory procedures, background information, and discussion of results for these experiments are provided. (Author/JN)

  20. A charged aerosol detector/chemiluminescent nitrogen detector/liquid chromatography/mass spectrometry system for regular and fragment compound analysis in drug discovery.

    PubMed

    Jiang, Yutao; Hascall, Daniel; Li, Delia; Pease, Joseph H

    2015-09-11

    In this paper, we introduce a high throughput LCMS/UV/CAD/CLND system that improves upon previously reported systems by increasing both the quantitation accuracy and the range of compounds amenable to testing, in particular, low molecular weight "fragment" compounds. This system consists of a charged aerosol detector (CAD) and chemiluminescent nitrogen detector (CLND) added to a LCMS/UV system. Our results show that the addition of CAD and CLND to LCMS/UV is more reliable for concentration determination for a wider range of compounds than either detector alone. Our setup also allows for the parallel analysis of each sample by all four detectors and so does not significantly increase run time per sample. Copyright © 2015 Elsevier B.V. All rights reserved.

  1. 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

    2017-12-01

    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 .

  2. 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. Copyright © 2016 John Wiley & Sons, Ltd.

  3. USSR Report, Chemistry

    DTIC Science & Technology

    1984-01-06

    Sep-Oct 83) ................................. ANALYTICAL CHEMISTRY Ionometric Determination of Copper in Organic Compounds S(S. L. Davydova, et al...Committee Reviews Progress in Fertilizer Industry (EKONOMICHESKAYA GAZETA, No 42, Oct 83) .................. 30 INORGANIC COMPOUNDS Speed of Ultrasound...Sep 83).. ........... .......... . . .. . . . . .... 39 NITROGEN COMPOUNDS Phototropy of Quaternary Ammonium Salts of N,N’-Bis- Substituted Diimides

  4. Hydroxymethyl phosphine compounds for use as diagnostic and therapeutic pharmaceuticals and method of making same

    DOEpatents

    Katti, K.V.; Karra, S.R.; Berning, D.E.; Smith, C.J.; Volkert, W.A.; Ketring, A.R.

    1999-01-05

    A compound and method of making a compound for use as a diagnostic or therapeutic pharmaceutical comprises at least one functionalized hydroxyalkyl phosphine donor group and one or more sulfur or nitrogen donor and a metal combined with the ligand. 21 figs.

  5. Uptake of organic sulfur and nitrogen compounds by aerosols

    USDA-ARS?s Scientific Manuscript database

    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...

  6. The nitrogen cycle on Mars

    NASA Technical Reports Server (NTRS)

    Mancinelli, Rocco L.

    1989-01-01

    Nirtogen is an essential element for the evolution of life, because it is found in a variety of biologically important molecules. Therefore, N is an important element to study from a exobiological perspective. In particular, fixed nitrogen is the biologically useful form of nitrogen. Fixed nitrogen is generally defines as NH3, NH4(+), NO(x), or N that is chemically bound to either inorganic or organic molecules, and releasable by hydrolysis to NH3 or NH4(+). On Earth, the vast majority of nitrogen exists as N2 in the atmosphere, and not in the fixes form. On early Mars the same situations probably existed. The partial pressure of N2 on early Mars was thought to be 18 mb, significantly less than that of Earth. Dinitrogen can be fixed abiotically by several mechanisms. These mechanisms include thernal shock from meteoritic infall and lightning, as well as the interaction of light and sand containing TiO2 which produces NH3 that would be rapidly destroyed by photolysis and reaction with OH radicals. These mechanisms could have been operative on primitive Mars.The chemical processes effecting these compounds and possible ways of fixing or burying N in the Martian environment are described. Data gathered in this laboratory suggest that the low abundance of nitrogen along (compared to primitive Earth) may not significantly deter the origin and early evolution of a nitrogen utilizing organisms. However, the conditions on current Mars with respect to nitrogen are quite different, and organisms may not be able to utilize all of the available nitrogen.

  7. Characteristics of microbial community functional structure of a biological coking wastewater treatment system.

    PubMed

    Joshi, Dev Raj; Zhang, Yu; Zhang, Hong; Gao, Yingxin; Yang, Min

    2018-01-01

    Nitrogenous heterocyclic compounds are key pollutants in coking wastewater; however, the functional potential of microbial communities for biodegradation of such contaminants during biological treatment is still elusive. Herein, a high throughput functional gene array (GeoChip 5.0) in combination with Illumina HiSeq2500 sequencing was used to compare and characterize the microbial community functional structure in a long run (500days) bench scale bioreactor treating coking wastewater, with a control system treating synthetic wastewater. Despite the inhibitory toxic pollutants, GeoChip 5.0 detected almost all key functional gene (average 61,940 genes) categories in the coking wastewater sludge. With higher abundance, aromatic ring cleavage dioxygenase genes including multi ring1,2diox; one ring2,3diox; catechol represented significant functional potential for degradation of aromatic pollutants which was further confirmed by Illumina HiSeq2500 analysis results. Response ratio analysis revealed that three nitrogenous compound degrading genes- nbzA (nitro-aromatics), tdnB (aniline), and scnABC (thiocyanate) were unique for coking wastewater treatment, which might be strong cause to increase ammonia level during the aerobic process. Additionally, HiSeq2500 elucidated carbozole and isoquinoline degradation genes in the system. These findings expanded our understanding on functional potential of microbial communities to remove organic nitrogenous pollutants; hence it will be useful in optimization strategies for biological treatment of coking wastewater. Copyright © 2017. Published by Elsevier B.V.

  8. Boron containing amino acid compounds and methods for their use

    DOEpatents

    Glass, John D.; Coderre, Jeffrey A.

    2000-01-01

    The present invention provides new boron containing amino acid compounds and methods for making these compounds by contacting melphalan or another nitrogen mustard derivative and sodium borocaptate. The present invention also provides a method of treating a mammal having a tumor by administering to the mammal a therapeutically effective amount of the new boron containing amino acid compounds.

  9. Methylotrophic bacteria in sustainable agriculture.

    PubMed

    Kumar, Manish; Tomar, Rajesh Singh; Lade, Harshad; Paul, Diby

    2016-07-01

    Excessive use of chemical fertilizers to increase production from available land has resulted in deterioration of soil quality. To prevent further soil deterioration, the use of methylotrophic bacteria that have the ability to colonize different habitats, including soil, sediment, water, and both epiphytes and endophytes as host plants, has been suggested for sustainable agriculture. Methylotrophic bacteria are known to play a significant role in the biogeochemical cycle in soil ecosystems, ultimately fortifying plants and sustaining agriculture. Methylotrophs also improve air quality by using volatile organic compounds such as dichloromethane, formaldehyde, methanol, and formic acid. Additionally, methylotrophs are involved in phosphorous, nitrogen, and carbon cycling and can help reduce global warming. In this review, different aspects of the interaction between methylotrophs and host plants are discussed, including the role of methylotrophs in phosphorus acquisition, nitrogen fixation, phytohormone production, iron chelation, and plant growth promotion, and co-inoculation of these bacteria as biofertilizers for viable agriculture practices.

  10. Recent changes in particulate air pollution over China observed from space and the ground: effectiveness of emission control.

    PubMed

    Lin, Jintai; Nielsen, Chris P; Zhao, Yu; Lei, Yu; Liu, Yang; McElroy, Michael B

    2010-10-15

    The Chinese government has moved aggressively since 2005 to reduce emissions of a number of pollutants including primary particulate matter (PM) and sulfur dioxide (SO(2)), efforts inadvertently aided since late 2008 by economic recession. Satellite observations of aerosol optical depth (AOD) and column nitrogen dioxide (NO(2)) provide independent indicators of emission trends, clearly reflecting the sharp onset of the recession in the fall of 2008 and rebound of the economy in the latter half of 2009. Comparison of AOD with ground-based observations of PM over a longer period indicate that emission-control policies have not been successful in reducing concentrations of aerosol pollutants at smaller size range over industrialized regions of China. The lack of success is attributed to the increasing importance of anthropogenic secondary aerosols formed from precursor species including nitrogen oxides (NO(x)), non-methane volatile organic compounds (NMVOC), and ammonia (NH(3)).

  11. Organo-Nitrogen Reactions on Jupiter

    NASA Astrophysics Data System (ADS)

    Lamothe, V. L.; Moses, J. I.

    2000-10-01

    Because the altitude regions for CH4 and NH3 photodissociation are physically separated from each other in the Jovian atmosphere, the possibility of forming organo-nitrogen compounds on Jupiter has been an uncertain problem [1,2,3,4,5]. Carbon- and nitrogen-bearing species do not interact significantly in laboratory experiments involving ultraviolet irradiation of CH4-NH3-H2 mixtures [6,7]. However, HCN and a variety of complex organo-nitrogen molecules are produced when methane in the above experiments is replaced by unsaturated hydrocarbons such as C2H2 or CH3C2H [8,9]. To determine the formation efficiency of organo-nitrogen compounds on Jupiter, we have added the reaction schemes proposed by [3,8,9] to a photochemical model of the Jovian troposphere and stratosphere. We find that HCN does not form in observable quantities unless a large tropospheric source of C2H2 exists (e.g., via lightning-induced chemistry, see [10]). Organo-nitrogen reactions are unlikely to be important on Jupiter --- chromophores are most likely due to inorganic compounds. References: [1] Strobel, D. F. (1973), J. Atmos. Sci. 30, 1205; [2] Kaye, J. A., and D. F. Strobel (1983a), Icarus\\ 55, 399; [3] Kaye, J. A., and D. F. Strobel (1983b), Icarus\\ 54, 417; [4] Tokunaga, A. T. et al./ (1981), Icarus\\ 48, 283; [5] Bézard, B. et al./ (1995), Icarus\\ 118, 384; [6] Raulin, F. et al. (1979), Icarus\\ 38, 358; [7] Ferris, J. P., and J. Y. Morimoto (1981), Icarus\\ 48, 118; [8] Ferris, J. P., and Y. Ishikawa (1988), J. Am. Chem. Soc. 110, 4306; [9] Ferris, J. et\\ al. (1992), Icarus\\ 95, 54; [10] Bétremieux, Y., and R. V. Yelle (1999), BAAS\\ 31, 1180.

  12. Quantifying the Global Nitrous Oxide Emissions Using a Trait-based Biogeochemistry Model

    NASA Astrophysics Data System (ADS)

    Zhuang, Q.; Yu, T.

    2017-12-01

    Nitrogen is an essential element for the global biogeochemical cycle. It is a key nutrient for organisms and N compounds including nitrous oxide significantly influence the global climate. The activities of bacteria and archaea are responsible for the nitrification and denitrification in a wide variety of environments, so microbes play an important role in the nitrogen cycle in soils. To date, most existing process-based models treated nitrification and denitrification as chemical reactions driven by soil physical variables including soil temperature and moisture. In general, the effect of microbes on N cycling has not been modeled in sufficient details. Soil organic carbon also affects the N cycle because it supplies energy to microbes. In my study, a trait-based biogeochemistry model quantifying N2O emissions from the terrestrial ecosystems is developed based on an extant process-based model TEM (Terrestrial Ecosystem Model). Specifically, the improvement to TEM includes: 1) Incorporating the N fixation process to account for the inflow of N from the atmosphere to biosphere; 2) Implementing the effects of microbial dynamics on nitrification process; 3) fully considering the effects of carbon cycling on N nitrogen cycling following the principles of stoichiometry of carbon and nitrogen in soils, plants, and microbes. The difference between simulations with and without the consideration of bacterial activity lies between 5% 25% based on climate conditions and vegetation types. The trait based module allows a more detailed estimation of global N2O emissions.

  13. Conjecture: imines as unidirectional photodriven molecular motors-motional and constitutional dynamic devices.

    PubMed

    Lehn, Jean-Marie

    2006-08-07

    Compounds containing the C==N group, such as imines and their derivatives, may undergo syn-anti isomerization by two different routes: 1) photochemically, by out-of-plane rotation around the carbon-nitrogen double bond through a "perpendicular" form, and 2) thermally, by in-plane nitrogen inversion through a "linear" transition state. When the two interconversions occur in sequence, a full, closed process is accomplished, restoring the initial state of the system along two different steps. In a chiral imine-type compound, for example, with an asymmetric center next to the C==N function, photoinduced rotation may be expected to occur in one sense in preference to the opposite one. Thus, photoisomerization followed by thermal isomerization in a chiral imine compound generates unidirectional molecular motion. Generally, imine-type compounds represent unidirectional molecular photomotors converting light energy into mechanical motion. As they are also able to undergo exchange of the carbonyl and amine partners, they present constitutional dynamics. Thus, imine-type compounds are double dynamic, motional, and constitutional devices.

  14. Effect of nitrogen species supply and mycorrhizal colonization on organosulfur and phenolic compounds in onions.

    PubMed

    Perner, Henrike; Rohn, Sascha; Driemel, Gregor; Batt, Natalie; Schwarz, Dietmar; Kroh, Lothar W; George, Eckhard

    2008-05-28

    The aim of the present study was to test whether variations in the root environment affect the content of health-related organosulfur compounds, total phenolic compounds, and flavonol glycoside concentrations in onions. For this purpose, greenhouse-grown onions ( Allium cepa L.) were either inoculated with a commercial arbuscular mycorrhizal inoculum or a sterile inoculum and were provided with two NH(4)(+):NO(3)(-) ratios as a nitrogen source. Onion growth, arbuscular mycorrhizal colonization rate, sugars, and nutrient element concentrations were also quantified. The plant antioxidant activity and quercetin monoglucoside and organosulfur compound concentrations increased with dominant nitrate supply. Furthermore, mycorrhizal colonization increased the antioxidant activity and also concentrations of the major quercetin glucosides. The present study provides clear evidence that antioxidant activity, quercetin glycosides, and organosulfur compounds can be increased in sufficiently supplied onion plants by dominant nitrate supply or application of arbuscular mycorrhizal fungi. This was probably due to increased precursor production and induced defense mechanisms.

  15. First-principles Study of Phonons in Structural Phase Change of Ge-Sb-Te Compounds

    NASA Astrophysics Data System (ADS)

    Song, Young-Sun; Kim, Jeongwoo; Kim, Minjae; Jhi, Seung-Hoon

    Ge-Sb-Te (GST) compounds, exhibiting substantial electrical and optical contrast at extremely fast switching modes, have attracted great attention for application as non-volatile memory devices. Despite extensive studies of GST compounds, the underlying mechanism for fast transitions between amorphous and crystalline phases is yet to be revealed. We study the vibrational property of various GST compounds and the role of nitrogen doping on phase-change processes using first-principles calculations. We find that a certain vibrational mode (Eu) plays a crucial role to determine transition temperatures, and that its frequency depends on the amount of Ge in GST. We also find that the nitrogen doping drives crystalline-amorphous transition at low power consumption modes. In addition, we discuss the effect of the spin-orbit coupling on vibration modes, which is known essential for correct description of the electrical property of GST. Our understanding of phonon modes in GST compounds paves the way for the improving the device performance especially in terms of switching speed and operating voltage.

  16. A study on heterogeneous photocatalytic degradation of various organic compounds using N-Tio2 under Uv-light irradiation

    NASA Astrophysics Data System (ADS)

    Srujana, Dhegam; Sailu, Chinta

    2018-04-01

    The aim of this work is to determine the photocatalytic degradation of mixture of four selected organic compounds are Congo Red (CR), Methylene Blue (MB), Diclofenaec (DC), 4-Chlorophenol (4-CP) have been subjected to Photo catalytic degradation by Ultraviolet (λ=254nm) radiation in presence of Nitrogen-doped Titanium dioxide (N-TiO2) catalyst. This paper focused on the enhancement of photo catalysis by modification of TiO2 employing non-metal ion (Nitrogen) doping. Experiments are conducted with a mixture of equal proportions of organic compounds (CR, MB, DC, and 4-CP) with combined concentrations of 10, 20, 30, 40 and 50 mg/l in water in a batch reactor in presence of N-TiO2catalyst with UV light (λ=254nm). The rate of degradation of each compound is determined by using spectrophotometer. The kinetics of degradation of the selected organic compounds is followed first order rate.

  17. Detection of Reduced Nitrogen Compounds at Rocknest Using the Sample Analysis At Mars (SAM) Instrument on the Mars Science Laboratory (MSL)

    NASA Technical Reports Server (NTRS)

    Stern, J. C.; Steele, A.; Brunner, A.; Coll, P.; Eigenbrode, J.; Franz, H. B.; Freissinet, C.; Glavin, D.; Jones, J. H.; Navarro-Gonzalez, R.; hide

    2013-01-01

    The Sample Analysis at Mars (SAM) instrument suite on the Mars Science Laboratory (MSL) Curiosity Rover detected nitrogen-bearing compounds during the pyrolysis of Rocknest material at Gale Crater. Hydrogen cyanide and acetonitrile were identified by the quadrupole mass spectrometer (QMS) both in direct evolved gas analysis (EGA). SAM carried out four separate analyses from Rocknest Scoop 5. A significant low temperature release was present in Rocknest runs 1-4, while a smaller high temperature release was also seen in Rocknest runs 1-3. Here we evaluate whether these compounds are indigenous to Mars or a pyrolysis product resulting from known terrestrial materials that are part of the SAM derivatization.

  18. Investigations into the chemical structure based selectivity of the microfabricated nitrogen-phosphorus detector

    DOE PAGES

    Brocato, Terisse A.; Hess, Ryan F.; Moorman, Matthew; ...

    2015-10-28

    The nitrogen and phosphorus atoms are constituents of some of the most toxic chemical vapors. Nitrogen-phosphorus gas chromatograph detectors (NPDs) rely on selective ionization of such compounds using ionization temperatures typically greater than 600 °C. NPDs have previously been reported to be 7*10 4× and 10 5× more sensitive for nitrogen and phosphorus, respectively, than for carbon. Presented here is an investigation of the structure-based selectivity of a microfabricated nitrogen-phosphorus detector (μNPD). The μNPD presented here is smaller than a dime and can be placed in a system that is 1/100th the size of a commercial NPD. Comparison of responsesmore » of such devices to homologous anilines (p-methoxyaniline, p-fluoroaniline, and aniline) revealed that detection selectivity, determined by the ratio of μNPD to nonselective flame ionization detector (FID) peak areas, is correlated with acid disassociation pK a values for the respective analine. Selectivity was determined to be greatest for p-methoxyaniline, followed by p-fluoroaniline, with aniline having the smallest response. The limit of detection for a nitrogen containing chemical, p-methoxyaniline, using the μNPD was determined to be 0.29 ng compared to 59 ng for a carbon chemical containing no nitrogen or phosphorus, 1,3,5-trimethybenzene. The μNPD presented here has increased detection for nitrogen and phosphorus compared to the FID and with a slight increase in detection of carbon compounds compared to commercial NPD's sensitivity to nitrogen and carbon.« less

  19. Spatial and temporal variations of water quality in the Belaya River Basin

    NASA Astrophysics Data System (ADS)

    Fashchevskaia, Tatiana; Motovilov, Yuri

    2016-04-01

    The aim of this research is to identify the spatiotemporal regularities of the maintenance of nitrogen compounds in the streams of the Belaya River basin. The dynamics of human activities in the catchment and intra and inter-annual changes in the water quality are analyzed for the period 1969-2007 years. The Belaya River is situated in the South Ural region and is one of the biggest tributary in the Volga River basin with catchment area of 142 000 km2. The Belaya River provides drinking water for a lot of settlements, it is used for industrial and agricultural water supply, fishery use, it is also a wastewater receiver for industry and housing and communal services. More than sixty years the diverse economic activities are carried out in the Belaya River basin, the intensity of this activity is characterized by high temporal variability. The leading industries in the region are oil mining, petroleum processing, chemistry and petro chemistry, mechanical engineering, metallurgy, power industry, timber industry. About 50% of the river basin is used for agriculture. Inter-annual dynamics of the nitrogen content in the river waters was identified on the basis of the long-term hydrological monitoring statistics at the 32 sites. It was found that the dynamics of the intensity of economic activities in the Belaya River basin is the cause statistically significant changes in the content of nitrogen compounds of the river network. Statistically homogeneous time intervals have been set for each monitoring site. Within these time intervals there were obtained averaged reliable quantitative estimations of water quality. Calculations showed that from the end of 1980 to 2007 the average long-term content of nutrients in the river waters is reduced in comparison with the previous period: ammonium nitrogen - in 1,6-7,5 times, nitrite nitrogen - 1,9-37,3 times, but the average concentration of nitrate nitrogen is increased in 1,4-6,6 times. Empirical probability distributions of ammonia nitrogen, nitrite nitrogen and nitrate nitrogen concentrations for various phases of the water regime in all investigated monitoring sites were approximated by Pearson type III curve and the averages of the concentration values for the water regime phases, the coefficient of variation and asymmetry, as well as the values of the concentrations of nitrogen compounds in the range of 1-95% of frequency ware estimated. It was found that by the end of the test period, the average long-term values for nitrogen compounds become smaller MAC in many streams of Belaya River basin that points to the suitability of river water quality for fishery use. However, in some points of river network there may be excess of MAC. Acknowledgements. The work was financially supported by the Russian Foundation for Basic Research (Grant 15-05-09022)

  20. 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...

  1. Method for inhibiting silica precipitation and scaling in geothermal flow systems

    DOEpatents

    Harrar, Jackson E.; Lorensen, Lyman E.; Locke, Frank E.

    1982-01-01

    A method for inhibiting silica scaling and precipitation in geothermal flow systems by on-line injection of low concentrations of cationic nitrogen-containing compounds, particularly polymeric imines, polymeric amines, and quaternary ammonium compounds.

  2. Composition of the water-soluble fraction of different cheeses.

    PubMed

    Taborda, Gonzalo; Molina, Elena; Martínez-Castro, Isabel; Ramos, Mercedes; Amigo, Lourdes

    2003-01-01

    Volatile and nonvolatile compounds present in the water-soluble fraction (WSF) and water-soluble fraction with molecular weight lower than 1000 Da (WSF < 1000 Da) of six Spanish cheeses, Cabrales, Idiazábal, Mahón, Manchego, Roncal, and a goat's milk cheese, were analyzed. Different nitrogen fractions (determined by Kjeldahl method), caseins (by capillary electrophoresis), peptides and amino acids (by HPLC), and volatile components (by dynamic headspace coupled to GC-MS) as well as mineral content in the cheese fractions were analyzed and compared. The different nitrogen and volatile compounds identified in the WSF were characteristic of each cheese variety. Cabrales cheese displayed the highest content of free amino acids and the highest quantity and variety of volatile compounds. The WSF < 1000 Da fraction was less representative, especially for volatile compounds, as some of the components were lost in the ultrafiltration. Alcohols were better recovered than ketones and esters.

  3. The neuromuscular blocking properties of a series of bis-quaternary tropeïnes

    PubMed Central

    Haining, C. G.; Johnston, R. G.; Smith, J. M.

    1960-01-01

    Linkage of two tropine esters through their nitrogen atoms by the chain -[CH2]m-O-CO-[CH2]n-CO-O-[CH2]m-, in which m was 2 or 3 and n varied from 0 to 6, gave compounds which produced neuromuscular block without depolarization. Reversibility be neostigmine was confirmed for a few compounds. Potency was found to depend upon the tropine ester employed and upon the values of n and m. Short duration and hypotensive properties were favoured by the higher values of n. The duration of action of the compound based on the phenylacetic acid ester of tropine, in which n=4 and m=2, varied considerably in different species. Epimerization, in which the relative positions of the methyl group and the linking chain on the quaternary tropane nitrogen atom were reversed, did not produce subtances having more favourable properties than those possessed by the unepimerized compounds. PMID:14398886

  4. Ab initio calculation of electronic structure and magnetic properties of R2Fe14BNx (R = Pr,Nd)

    NASA Astrophysics Data System (ADS)

    Tian, Guang; Zha, Liang; Yang, Wenyun; Qiao, Guanyi; Wang, Changsheng; Yang, Yingchang; Yang, Jinbo

    2018-05-01

    The site preference of N atom for R2Fe14BNx (R= Pr, Nd) and the interstitial nitrogen effect on the magnetic properties have been studied by the first-principles method. It was found that the nitrogen is more likely to occupy the 4e site for Pr2Fe14BNx compound, while 4f site for Nd2Fe14BNx. When N atoms entering some specific crystal sites (such as 2a and 4f), the total magnetic moments of these compounds are not reduced, but slightly increased. Although the doping of N may reduce the total magnetic moments of some R2Fe14B compounds in the cases of optimal occupancy, the volumetric effect caused by N doping can still change the electron density distributions of Fe near the Fermi level, improving the magnetic ordering temperature of such compounds.

  5. Preparation of nanoporous metal foam from high nitrogen transition metal complexes

    DOEpatents

    Tappan, Bryce C.; Huynh, My Hang V.; Hiskey, Michael A.; Son, Steven F.; Oschwald, David M.; Chavez, David E.; Naud, Darren L.

    2006-11-28

    Nanoporous metal foams are prepared by ignition of high nitrogen transition metal complexes. The ammonium salts of iron(III) tris[bi(tetrazolato)-amine], cobalt(III) tris(bi(tetrazolato)amine), and high nitrogen compounds of copper and silver were prepared as loose powders, pressed into pellets and wafers, and ignited under an inert atmosphere to form nanoporous metal foam monoliths having very high surface area and very low density.

  6. Nitrogen Limited Red and Green Leaf Lettuce Accumulate Flavonoid Glycosides, Caffeic Acid Derivatives, and Sucrose while Losing Chlorophylls, Β-Carotene and Xanthophylls.

    PubMed

    Becker, Christine; Urlić, Branimir; Jukić Špika, Maja; Kläring, Hans-Peter; Krumbein, Angelika; Baldermann, Susanne; Goreta Ban, Smiljana; Perica, Slavko; Schwarz, Dietmar

    2015-01-01

    Reduction of nitrogen application in crop production is desirable for ecological and health-related reasons. Interestingly, nitrogen deficiency can lead to enhanced concentrations of polyphenols in plants. The reason for this is still under discussion. The plants' response to low nitrogen concentration can interact with other factors, for example radiation intensity. We cultivated red and green leaf lettuce hydroponically in a Mediterranean greenhouse, supplying three different levels of nitrogen (12 mM, 3 mM, 0.75 mM), either in full or reduced (-50%) radiation intensity. In both red and green lettuce, we found clear effects of the nitrogen treatments on growth characteristics, phenolic and photosynthetic compounds, nitrogen, nitrate and carbon concentration of the plants. Interestingly, the concentrations of all main flavonoid glycosides, caffeic acid derivatives, and sucrose increased with decreasing nitrogen concentration, whereas those of chlorophylls, β-carotene, neoxanthin, lactucaxanthin, all trans- and cis-violaxanthin decreased. The constitutive concentrations of polyphenols were lower in the green cultivar, but their relative increase was more pronounced than in the red cultivar. The constitutive concentrations of chlorophylls, β-carotene, neoxanthin, all trans- and cis-violaxanthin were similar in red and green lettuce and with decreasing nitrogen concentration they declined to a similar extent in both cultivars. We only detected little influence of the radiation treatments, e.g. on anthocyanin concentration, and hardly any interaction between radiation and nitrogen concentration. Our results imply a greater physiological plasticity of green compared to the red lettuce regarding its phenolic compounds. They support the photoprotection theory regarding anthocyanins as well as the theory that the deamination activity of phenylalanine ammonia-lyase drives phenylpropanoid synthesis.

  7. Nitrogen Limited Red and Green Leaf Lettuce Accumulate Flavonoid Glycosides, Caffeic Acid Derivatives, and Sucrose while Losing Chlorophylls, Β-Carotene and Xanthophylls

    PubMed Central

    Becker, Christine; Urlić, Branimir; Jukić Špika, Maja; Kläring, Hans-Peter; Krumbein, Angelika; Baldermann, Susanne; Goreta Ban, Smiljana; Perica, Slavko; Schwarz, Dietmar

    2015-01-01

    Reduction of nitrogen application in crop production is desirable for ecological and health-related reasons. Interestingly, nitrogen deficiency can lead to enhanced concentrations of polyphenols in plants. The reason for this is still under discussion. The plants’ response to low nitrogen concentration can interact with other factors, for example radiation intensity. We cultivated red and green leaf lettuce hydroponically in a Mediterranean greenhouse, supplying three different levels of nitrogen (12 mM, 3 mM, 0.75 mM), either in full or reduced (-50%) radiation intensity. In both red and green lettuce, we found clear effects of the nitrogen treatments on growth characteristics, phenolic and photosynthetic compounds, nitrogen, nitrate and carbon concentration of the plants. Interestingly, the concentrations of all main flavonoid glycosides, caffeic acid derivatives, and sucrose increased with decreasing nitrogen concentration, whereas those of chlorophylls, β-carotene, neoxanthin, lactucaxanthin, all trans- and cis-violaxanthin decreased. The constitutive concentrations of polyphenols were lower in the green cultivar, but their relative increase was more pronounced than in the red cultivar. The constitutive concentrations of chlorophylls, β-carotene, neoxanthin, all trans- and cis-violaxanthin were similar in red and green lettuce and with decreasing nitrogen concentration they declined to a similar extent in both cultivars. We only detected little influence of the radiation treatments, e.g. on anthocyanin concentration, and hardly any interaction between radiation and nitrogen concentration. Our results imply a greater physiological plasticity of green compared to the red lettuce regarding its phenolic compounds. They support the photoprotection theory regarding anthocyanins as well as the theory that the deamination activity of phenylalanine ammonia-lyase drives phenylpropanoid synthesis. PMID:26569488

  8. [Nitrogen pool in northern taiga larch forests of Central Siberia].

    PubMed

    Shugaleĭ, L S; Vedrova, E F

    2004-01-01

    The pools of nitrogen in different blocks of forest ecosystems and its cycle in the soil are considered. It is shown that the bulk of nitrogen concentrates in the soil and dead organic matter (necromass) of an ecosystem. The nitrogen pool of forest litters and soils consists by 83-93% of the inert compounds that cannot be involved in the biological cycle. Mineralization of organic nitrogen-containing substances in the litters and soils usually yields ammonium as an end product. The amount of nitrogen mineralized over the growing season is partially expended for annual plant increment (30-65%) and immobilization (12-17%), with its large proportion being found in the soil.

  9. Management of Multiple Nitrogen Sources during Wine Fermentation by Saccharomyces cerevisiae.

    PubMed

    Crépin, Lucie; Truong, Nhat My; Bloem, Audrey; Sanchez, Isabelle; Dequin, Sylvie; Camarasa, Carole

    2017-03-01

    During fermentative growth in natural and industrial environments, Saccharomyces cerevisiae must redistribute the available nitrogen from multiple exogenous sources to amino acids in order to suitably fulfill anabolic requirements. To exhaustively explore the management of this complex resource, we developed an advanced strategy based on the reconciliation of data from a set of stable isotope tracer experiments with labeled nitrogen sources. Thus, quantifying the partitioning of the N compounds through the metabolism network during fermentation, we demonstrated that, contrary to the generally accepted view, only a limited fraction of most of the consumed amino acids is directly incorporated into proteins. Moreover, substantial catabolism of these molecules allows for efficient redistribution of nitrogen, supporting the operative de novo synthesis of proteinogenic amino acids. In contrast, catabolism of consumed amino acids plays a minor role in the formation of volatile compounds. Another important feature is that the α-keto acid precursors required for the de novo syntheses originate mainly from the catabolism of sugars, with a limited contribution from the anabolism of consumed amino acids. This work provides a comprehensive view of the intracellular fate of consumed nitrogen sources and the metabolic origin of proteinogenic amino acids, highlighting a strategy of distribution of metabolic fluxes implemented by yeast as a means of adapting to environments with changing and scarce nitrogen resources. IMPORTANCE A current challenge for the wine industry, in view of the extensive competition in the worldwide market, is to meet consumer expectations regarding the sensory profile of the product while ensuring an efficient fermentation process. Understanding the intracellular fate of the nitrogen sources available in grape juice is essential to the achievement of these objectives, since nitrogen utilization affects both the fermentative activity of yeasts and the formation of flavor compounds. However, little is known about how the metabolism operates when nitrogen is provided as a composite mixture, as in grape must. Here we quantitatively describe the distribution through the yeast metabolic network of the N moieties and C backbones of these nitrogen sources. Knowledge about the management of a complex resource, which is devoted to improvement of the use of the scarce N nutrient for growth, will be useful for better control of the fermentation process and the sensory quality of wines. Copyright © 2017 American Society for Microbiology.

  10. Management of Multiple Nitrogen Sources during Wine Fermentation by Saccharomyces cerevisiae

    PubMed Central

    Crépin, Lucie; Truong, Nhat My; Bloem, Audrey; Sanchez, Isabelle; Dequin, Sylvie

    2017-01-01

    ABSTRACT During fermentative growth in natural and industrial environments, Saccharomyces cerevisiae must redistribute the available nitrogen from multiple exogenous sources to amino acids in order to suitably fulfill anabolic requirements. To exhaustively explore the management of this complex resource, we developed an advanced strategy based on the reconciliation of data from a set of stable isotope tracer experiments with labeled nitrogen sources. Thus, quantifying the partitioning of the N compounds through the metabolism network during fermentation, we demonstrated that, contrary to the generally accepted view, only a limited fraction of most of the consumed amino acids is directly incorporated into proteins. Moreover, substantial catabolism of these molecules allows for efficient redistribution of nitrogen, supporting the operative de novo synthesis of proteinogenic amino acids. In contrast, catabolism of consumed amino acids plays a minor role in the formation of volatile compounds. Another important feature is that the α-keto acid precursors required for the de novo syntheses originate mainly from the catabolism of sugars, with a limited contribution from the anabolism of consumed amino acids. This work provides a comprehensive view of the intracellular fate of consumed nitrogen sources and the metabolic origin of proteinogenic amino acids, highlighting a strategy of distribution of metabolic fluxes implemented by yeast as a means of adapting to environments with changing and scarce nitrogen resources. IMPORTANCE A current challenge for the wine industry, in view of the extensive competition in the worldwide market, is to meet consumer expectations regarding the sensory profile of the product while ensuring an efficient fermentation process. Understanding the intracellular fate of the nitrogen sources available in grape juice is essential to the achievement of these objectives, since nitrogen utilization affects both the fermentative activity of yeasts and the formation of flavor compounds. However, little is known about how the metabolism operates when nitrogen is provided as a composite mixture, as in grape must. Here we quantitatively describe the distribution through the yeast metabolic network of the N moieties and C backbones of these nitrogen sources. Knowledge about the management of a complex resource, which is devoted to improvement of the use of the scarce N nutrient for growth, will be useful for better control of the fermentation process and the sensory quality of wines. PMID:28115380

  11. An enhanced approach for the use of satellite-derived leaf area index values in dry deposition modeling in the Athabasca oil sands region.

    PubMed

    Davies, Mervyn; Cho, Sunny; Spink, David; Pauls, Ron; Desilets, Michael; Shen, Yan; Bajwa, Kanwardeep; Person, Reid

    2016-12-15

    In the Athabasca oil sands region (AOSR) of Northern Alberta, the dry deposition of sulphur and nitrogen compounds represents a major fraction of total (wet plus dry) deposition due to oil sands emissions. The leaf area index (LAI) is a critical parameter that affects the dry deposition of these gaseous and particulate compounds to the surrounding boreal forest canopy. For this study, LAI values based on Moderate Resolution Imaging Spectroradiometer satellite imagery were obtained and compared to ground-based measurements, and two limitations with the satellite data were identified. The satellite LAI data firstly represents one-sided LAI values that do not account for the enhanced LAI associated with needle leaf geometry, and secondly, underestimates LAI in winter-time northern latitude regions. An approach for adjusting satellite LAI values for different boreal forest cover types, as a function of time of year, was developed to produce more representative LAI values that can be used by air quality sulphur and nitrogen deposition models. The application of the approach increases the AOSR average LAI for January from 0.19 to 1.40, which represents an increase of 637%. Based on the application of the CALMET/CALPUFF model system, this increases the predicted regional average dry deposition of sulphur and nitrogen compounds for January by factors of 1.40 to 1.30, respectively. The corresponding AOSR average LAI for July increased from 2.8 to 4.0, which represents an increase of 43%. This increases the predicted regional average dry deposition of sulphur and nitrogen compounds for July by factors of 1.28 to 1.22, respectively. These findings reinforce the importance of the LAI metric for predicting the dry deposition of sulphur and nitrogen compounds. While satellite data can provide enhanced spatial and temporal resolution, adjustments are identified to overcome associated limitations. This work is considered to have application for other deposition model studies where dry deposition represents a significant fraction of total deposition. Copyright © 2016 Elsevier Ltd. All rights reserved.

  12. Dry deposition of reduced and reactive nitrogen: A surrogate surfaces approach

    NASA Astrophysics Data System (ADS)

    Shahin, Usama Mohammed

    Nitrogen deposition constitutes an important component of acidic deposition to terrestrial surfaces. However, deposition flux and ambient concentration measurement methods and are still under development. A new sampler using water as a surrogate surface was developed in the Department of Environmental Engineering at Illinois Institute of Technology. This study investigated nitrate and ammonia dry deposition to the water surface sampler, a Nylasorb filter, a citric acid impregnated filter, and a greased strip on the dry deposition plate. The nitrogen containing species that may be responsible for nitrate dry deposition to the WSS include nitrogen monoxide (NO), nitrogen dioxide (NO2), peroxyacetyl nitrate (PAN), nitrous acid (HNO2), nitric acid (HNO3), and particulate nitrate. The experimental measurements showed that HNO3 and particulate nitrate are the major nitrate contributors to the WSS. Ammonia sources to the water surface are ammonia gas (NH3) and ammonium (NH4+). The experimental results showed that these two species are the sole sources to ammonium deposition. Comparison between the measured deposition velocity of SO2, and HNO3, shows that their dry deposition velocities are statistically the same at the 95% confidence level and NH3 deposition velocity and the water evaporation rate are also the same. It was also shown that the air side MTC of two different compounds were correlated to the square root of the inverse of the molecular weight for compounds. The measured MTC was tested by the application of two models, the resistance model and the water evaporation model. The resistance model prediction of the MTC was very close to the measured value but the evaporation model prediction was not. This result is compatible with the finding of Yi, (1997) who used the same WSS for measurements of SO2. The experimental data collected in this research project was used to develop an empirical model to measure the MTC that is [kl/over D] = 0.0426 ([lv/rho/over /mu])0.8([/mu/over /rho [ D

  13. Carbon source recovery from excess sludge by mechanical disintegration for biological denitrification.

    PubMed

    Zubrowska-Sudol, M

    2018-04-01

    The goal of the study was to evaluate the possibility of carbon source recovery from excess sludge by mechanical disintegration for biological denitrification. The total efficiency of denitrification, unit demand for organic compounds for denitrification, unit volume of disintegrated sludge and unit cost of nitrogen removal as a function of energy density used for excess sludge disintegration (70, 140 and 210 kJ/L) were analyzed. In the study a full-scale disc disintegrator was used (motor power: 30 kWh, motor speed: 2,950 rpm). It was shown that the amounts of organic compounds released from the activated sludge flocs at all tested levels of energy density are high enough to be used to intensify the removal of nitrogen compounds from wastewater. It was also documented that the energy density provided during process of disintegration was an important factor determining the characteristics of organic compounds obtained under the disintegration for their use in order to intensify the process of denitrification. The highest value of total efficiency of denitrification (50.5 ± 3.1 mg N/L) was obtained for carbon source recovery from excess sludge at 70 kJ/L, but the lowest unit cost of nitrogen removal occurred for 140 kJ/L (0.0019 ± 0.0011 EUR/g N).

  14. Nanoscale carbon materials from hydrocarbons pyrolysis: Structure, chemical behavior, utilisation for non-aqueous supercapacitors

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Savilov, Serguei V., E-mail: savilov@chem.msu.ru; Strokova, Natalia E.; Ivanov, Anton S.

    Highlights: • N-doped and regular carbon nanomaterials were obtained by pyrolitic technique. • Dynamic vapor sorption of different solvents reveals smaller S{sub BET} values. • Steric hindrance and specific chemical interactions are the reasons for this. • Nitrogen doping leads to raise of capacitance and coulombic efficiency with non-aqueous N-containing electrolyte. - Abstract: This work systematically studies adsorption properties of carbon nanomaterials that are synthesized through hydrocarbons that is a powerful technique to fabricate different kinds of carbon materials, e.g., nanotubes, nanoshells, onions, including nitrogen substituted. The adsorption properties of the as-synthesized carbons are achieved by low temperature nitrogen adsorptionmore » and organic vapors sorption. Heptane, acetonitrile, water, ethanol, benzene and 1-methylimidazole, which are of great importance for development of supercapacitors, are used as substrates. It is discovered that while nitrogen adsorption reveals a high specific surface area, this parameter for most of organic compounds is rather small depending not only on the size of its molecule but also on chemical interactions for a pair adsorbent–adsorbate. The experimental values of heat of adsorption for carbon and N-substituted structures, when Coulomb cross-coupling of nitrogen atoms in adsorbent and adsorbate takes place, confirms this supposition.« less

  15. Procedures for making gaseous industrial waste safe

    NASA Astrophysics Data System (ADS)

    Matros, Yu Sh; Noskov, Aleksandr S.

    1990-10-01

    The application of various methods (adsorption, absorption, thermal afterburning, catalytic purification, and others) for the removal of sulphur and nitrogen oxides, toxic organic compounds, hydrogen sulphide, and carbon monoxide from industrial waste gases is described. Much attention is devoted to the catalytic procedure for making the gases safe using an energy collecting non-stationary method (reversible process). The advantages and limitations of various gas purification methods are considered. The bibliography includes 279 references.

  16. PRODUCTION, MANAGEMENT AND THE ENVIRONMENT SYMPOSIUM: Measurement and mitigation of reactive nitrogen species from swine and poultry production.

    PubMed

    Powers, W; Capelari, M

    2017-05-01

    Reactive nitrogen (Nr) species include oxides of nitrogen [N; nitric oxide, nitrogen dioxide and nitrous oxide (NO)], anions (nitrate and nitrite), and amine derivatives [ammonia (NH), ammonium salts and urea]. Of the different Nr species, air emissions from swine and poultry facilities are predominantly NH followed by NO. Excreta emissions are NH, ammonium ions, and urea with trace amounts of nitrate and nitrite. Farm systems and practices that handle manure as a wet product without pH modification favor almost exclusive NH production. Systems and practices associated with dry manure handling and bedded systems emit more NH than NO. Results from a turkey grow-out study estimated that just under 1% of consumed N was emitted as NO from housing, compared with just under 11% emitted as NH. Despite generally less NO emissions from animal housing compared with crop field emissions, NO emissions from housing are often greater than estimated. Lagoon systems emit more NO than either slurry or deep pit swine systems. Deep pit swine buildings emit only one-third the NO that is emitted from deep bedded swine systems. Laying hen, broiler chicken, and turkey buildings emit over 4 times as much NO as swine housing, on a weight-adjusted basis. Critical control points for mitigation center on: 1) reducing the amount of N excreted and, therefore, excreted N available for loss to air or water during housing, manure storage, or following land application of manures; 2) capturing excreted N to prevent release of N-containing compounds to air, water, or soil resources; or 3) conversion or treatment of N-containing compounds to non-reactive N gas.

  17. Compound-specific amino acid isotopic analyses of invertebrates in the Chukchi Sea: New insights on food web dynamics

    NASA Astrophysics Data System (ADS)

    Zhang, M.; Cooper, L. W.; Biasatti, D. M.; Kedra, M.; Grebmeier, J. M.

    2016-02-01

    Food web dynamics in the Chukchi Sea have been previously evaluated using bulk analysis of stable carbon and nitrogen isotopes of organisms. However, recent advances in compound-specific stable isotope analysis of amino acids indicate the potential to better identify the contributions of different dietary sources (e.g., pelagic vs. benthic, ice algae vs. phytoplankton) and to resolve complexities of food web structure that are difficult to address with bulk isotope analysis. Here we combine amino acid δ13C and δ15N data measured from primary producers and tissues of bivalves, polychaetes and other benthic invertebrates collected during two cruises in the summer of 2013 and 2015 in the Pacific Arctic. The results showed spatial variation of carbon isotope values in amino acids with difference up to 6 per mil for each individual species or taxa studied, indicating a shift in the food-web baseline geographically. Furthermore, the spatial variation in isotopic values was related to environmental factors, specifically sea ice extent, and total organic carbon, total organic nitrogen and the carbon/nitrogen ratio of the organic fractions of surface sediments. Results also indicated that trophic levels, as estimated by differences in the nitrogen isotope composition of glutamic acid and phenylalanine [Δ15Nglu-phe (δ15Nglu - δ15Nphe)], varied spatially by 0.5 to 1.5 trophic levels for certain species or taxa such as Macoma calcarea, Maldanidae and Ampelisca, indicating trophic level shifts that were associated with the food quality of organic matter in the organic fraction of the sediments. These results can be potentially used to predict future food web change in this high latitude marine system that is known for its ecological importance and on-going environmental changes, including warming and sea ice decline.

  18. Molecular Analysis of Ammonia-Oxidizing Bacteria of the β Subdivision of the Class Proteobacteria in Compost and Composted Materials

    PubMed Central

    Kowalchuk, George A.; Naoumenko, Zinaida S.; Derikx, Piet J. L.; Felske, Andreas; Stephen, John R.; Arkhipchenko, Irina A.

    1999-01-01

    Although the practice of composting animal wastes for use as biofertilizers has increased in recent years, little is known about the microorganisms responsible for the nitrogen transformations which occur in compost and during the composting process. Ammonia is the principle available nitrogenous compound in composting material, and the conversion of this compound to nitrite in the environment by chemolithotrophic ammonia-oxidizing bacteria is an essential step in nitrogen cycling. Therefore, the distribution of ammonia-oxidizing members of the β subdivision of the class Proteobacteria in a variety of composting materials was assessed by amplifying 16S ribosomal DNA (rDNA) and 16S rRNA by PCR and reverse transcriptase PCR (RT-PCR), respectively. The PCR and RT-PCR products were separated by denaturing gradient gel electrophoresis (DGGE) and were identified by hybridization with a hierarchical set of oligonucleotide probes designed to detect ammonia oxidizer-like sequence clusters in the genera Nitrosospira and Nitrosomonas. Ammonia oxidizer-like 16S rDNA was detected in almost all of the materials tested, including industrial and experimental composts, manure, and commercial biofertilizers. A comparison of the DGGE and hybridization results after specific PCR and RT-PCR suggested that not all of the different ammonia oxidizer groups detected in compost are equally active. amoA, the gene encoding the active-site-containing subunit of ammonia monooxygenase, was also targeted by PCR, and template concentrations were estimated by competitive PCR. Detection of ammonia-oxidizing bacteria in the composts tested suggested that such materials may not be biologically inert with respect to nitrification and that the fate of nitrogen during composting and compost storage may be affected by the presence of these organisms. PMID:9925559

  19. Occurrence of anthropogenic organic compounds and nutrients in source and finished water in the Sioux Falls area, South Dakota, 2009-10

    USGS Publications Warehouse

    Hoogestraat, Galen K.

    2012-01-01

    Anthropogenic organic compounds (AOCs) in drinking-water sources commonly are derived from municipal, agricultural, and industrial wastewater sources, and are a concern for water-supply managers. A cooperative study between the city of Sioux Falls, S. Dak., and the U.S. Geological Survey was initiated in 2009 to (1) characterize the occurrence of anthropogenic organic compounds in the source waters (groundwater and surface water) to water supplies in the Sioux Falls area, (2) determine if the compounds detected in the source waters also are present in the finished water, and (3) identify probable sources of nitrate in the Big Sioux River Basin and determine if sources change seasonally or under different hydrologic conditions. This report presents analytical results of water-quality samples collected from source waters and finished waters in the Sioux Falls area. The study approach included the collection of water samples from source and finished waters in the Sioux Falls area for the analyses of AOCs, nutrients, and nitrogen and oxygen isotopes in nitrate. Water-quality constituents monitored in this study were chosen to represent a variety of the contaminants known or suspected to occur within the Big Sioux River Basin, including pesticides, pharmaceuticals, sterols, household and industrial products, polycyclic aromatic hydrocarbons, antibiotics, and hormones. A total of 184 AOCs were monitored, of which 40 AOCs had relevant human-health benchmarks. During 11 sampling visits, 45 AOCs (24 percent) were detected in at least one sample of source or finished water, and 13 AOCs were detected in at least 20 percent of all samples. Concentrations of detected AOCs were all less than 1 microgram per liter, except for two AOCs in multiple samples from the Big Sioux River, and one AOC in finished-water samples. Concentrations of AOCs were less than 0.1 microgram per liter in more than 75 percent of the detections. Nutrient concentrations varied seasonally in source-water samples from surface water and groundwater. In the Big Sioux River, nitrite plus nitrate concentrations were typically less than 1 milligram per liter as nitrogen, and reached a maximum of 4.06 milligrams per liter as nitrogen following a June 2010 storm. Nitrite plus nitrate concentrations in groundwater ranged from less than 0.1 to 0.701 milligram per liter as nitrogen. Eight of the AOCs detected have a human-health benchmark that could be used to evaluate the concentrations in a human-health context. Four AOCs had maximum concentrations within an order of magnitude of the benchmark, indicating that additional monitoring of the compound may be warranted. Three herbicides (atrazine, metolachlor, and prometon) and one degradate (deethylatrazine) were detected in finished-water samples as frequently as in source-water samples. The concentrations of herbicides in source water varied by an order of magnitude from the period of peak use (early summer) to the winter months. Groundwater and finished-water concentrations of atrazine were similar for the six sampling dates when groundwater was the only source water used. Upstream wastewater discharges contributed a fairly small percentage of the flow to the Big Sioux River near Sioux Falls, but several AOCs associated with wastewater were frequently detected. The interpretation of all potential sources of nitrogen cannot be accomplished by use of nitrogen and oxygen isotopes in nitrate alone, but provides a qualitative indication that very little nitrate originates from excess fertilizer runoff, and most nitrate originates from municipal wastewater effluent, manure runoff (either from field application or feeding operations), or fertilizers mineralized by processes in the soil.

  20. Syntheses, crystal structures and characterization of nitrogen-rich salts based on bis (1H-tetrazol-5-yl) methanone oxime

    NASA Astrophysics Data System (ADS)

    Lin, Xinyu; Guo, Weiming; Zhang, Tianhe; Huang, Jingru; Tong, Yi; Zhang, Tonglai

    2017-08-01

    Two nitrogen-rich energetic salts (NH4)2(bto) (1) and (NH3OH)2(bto)·H2O (2) [H2bto = Bis (1H-tetrazol-5-yl) methanone oxime] were synthesized by an improved method in which water was used as solvent. These compounds were characterized by FT-IR spectroscopy, elemental analysis and single crystal X-ray diffraction. Their crystal structures were confirmed to belong to monoclinic system with space group P21 for 1 and Pc for 2, respectively. The detailed thermal behaviours were investigated by using differential scanning calorimetry (DSC) and thermogravimetric method (TG) (decomposition temperature >250 °C). The enthalpies of formation were calculated through the experimental values of combustion enthalpy. In addition, the sensitivities toward impact and friction were tested with standard methods, and those results indicated that two compounds are all insensitive (impact >40 J and friction >360 N). In short, both of the compounds show potential usages as energetic materials. The improved process opens a door for exploring nitrogen-rich salts based on Bis (1H-tetrazol-5-yl) methanone oxime.

  1. Hypoxanthine enhances the cured meat taste

    PubMed Central

    Nakamura, Yukinobu; Yoshida, Yuka; Hattori, Akihito

    2016-01-01

    Abstract We evaluated the enhancement of cured meat taste during maturation by sensory analysis. We focused on the heat‐stable sarcoplasmic fraction (HSSF) to identify the factors related to cured meat taste. Because the dry matter of HSSF contained more than 30% nitrogen, nitrogen compounds such as free amino acids, small peptides and adenosine triphosphate‐related compounds seemed to be the important components of HSSF. The samples cured with HSSF for 2 h exhibited the same taste profile as ones cured without HSSF for 168 h. Therefore, the changes in the amount and fractions of nitrogen compounds were examined in HSSF during incubation from 0 to 168 h. The concentration of hypoxanthine (Hx) gradually increased, while inosine‐5′‐monophosphate decreased during the incubation. The samples cured with pickles containing various concentrations of Hx were subjected to sensory analysis. The addition of Hx, in a dose‐dependent fashion, enhanced cured meat taste by maturation for 2 h. It was concluded that Hx is essential for the enhancement of cured meat taste. PMID:27169902

  2. Binding of nitrogen-containing bisphosphonates (N-BPs) to the Trypanosoma cruzi farnesyl diphosphate synthase homodimer

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Huang, Chuan-Hsiang; Gabelli, Sandra B.; Oldfield, Eric

    Bisphosphonates (BPs) are a class of compounds that have been used extensively in the treatment of osteoporosis and malignancy-related hypercalcemia. Some of these compounds act through inhibition of farnesyl diphosphate synthase (FPPS), a key enzyme in the synthesis of isoprenoids. Recently, nitrogen-containing bisphosphonates (N-BPs) used in bone resorption therapy have been shown to be active against Trypanosoma cruzi, the parasite that causes American trypanosomiasis (Chagas disease), suggesting that they may be used as anti-trypanosomal agents. The crystal structures of TcFPPS in complex with substrate (isopentenyl diphosphate, IPP) and five N-BP inhibitors show that the C-1 hydroxyl and the nitrogen-containing groupsmore » of the inhibitors alter the binding of IPP and the conformation of two TcFPPS residues, Tyr94 and Gln167. Isothermal titration calorimetry experiments suggest that binding of the first N-BPs to the homodimeric TcFPPS changes the binding properties of the second site. This mechanism of binding of N-BPs to TcFPPS is different to that reported for the binding of the same compounds to human FPPS.« less

  3. 77 FR 74115 - Approval and Promulgation of Air Quality Implementation Plans; Pennsylvania; The 2002 Base Year...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-12-13

    ... ), volatile organic compounds (VOCs), ammonia (NH 3 ), and sulfur dioxide (SO 2 ). EPA has reviewed the... , coarse particles (PM 10 ), nitrogen oxides (NO X ), volatile organic compounds (VOCs), ammonia (NH 3...

  4. Method for inhibiting silica precipitation and scaling in geothermal flow systems

    DOEpatents

    Harrar, J.E.; Lorensen, L.E.; Locke, F.E.

    1980-06-13

    A method for inhibiting silica scaling and precipitation in geothermal flow systems by on-line injection of low concentrations of cationic nitrogen-containing compounds, particularly polymeric imines, polymeric amines, and quaternary ammonium compounds is described.

  5. PA-824 Kills Nonreplicating Mycobacterium tuberculosis by Intracellular NO Release

    PubMed Central

    Singh, Ramandeep; Manjunatha, Ujjini; Boshoff, Helena I. M.; Ha, Young Hwan; Niyomrattanakit, Pornwaratt; Ledwidge, Richard; Dowd, Cynthia S.; Lee, Ill Young; Kim, Pilho; Zhang, Liang; Kang, Sunhee; Keller, Thomas H.; Jiricek, Jan; Barry, Clifton E.

    2009-01-01

    Bicyclic nitroimidazoles, including PA-824, are exciting candidates for the treatment of tuberculosis. These prodrugs require intracellular activation for their biological function. We found that Rv3547 is a deazaflavin-dependent nitroreductase (Ddn) that converts PA-824 into three primary metabolites; the major one is the corresponding des-nitroimidazole (des-nitro). When derivatives of PA-824 were used, the amount of des-nitro metabolite formed was highly correlated with anaerobic killing of Mycobacterium tuberculosis (Mtb). Des-nitro metabolite formation generated reactive nitrogen species, including nitric oxide (NO), which are the major effectors of the anaerobic activity of these compounds. Furthermore, NO scavengers protected the bacilli from the lethal effects of the drug. Thus, these compounds may act as intracellular NO donors and could augment a killing mechanism intrinsic to the innate immune system. PMID:19039139

  6. A reconnaissance of the effects of a forest fire on water quality in Kings Canyon National Park, California

    USGS Publications Warehouse

    Hoffman, Ray J.; Ferreira, Rodger F.

    1976-01-01

    Following two forest fires in the Roaring River drainage basin, Kings Canyon National Park, Calif., water samples were collected from May to July 1974 to determine water-quality changes resulting from the fires. Field measurements included alkalinity , pH, specific conductance, temperature, and discharge. Samples were analyzed in the laboratory for major dissolved chemical constituents, selected plant nutrients, trace metals, suspended sediment, total organic carbon, and seston. Periphytic algae and benthic invertebrate samples were collected. A noticeable increase in the concentration of nitrogen was found in Roaring River immediately downstream from the Moraine Creek fire. The increase in the concentration of inorganic nitrogen compounds, however, was not great enough to pose a serious threat to the aquatic ecosystem. High total organic nitrogen concentrations may have been due, in part, to factors other than the effect of fire. The results of other water-quality measurements were typical of dilute Sierra Nevada streams and indicate that Roaring River was not adversely affected by the fires. (Woodard-USGS)

  7. Synthesis of Novel Aza-aromatic Curcuminoids with Improved Biological Activities towards Various Cancer Cell Lines.

    PubMed

    Theppawong, Atiruj; Van de Walle, Tim; Grootaert, Charlotte; Bultinck, Margot; Desmet, Tom; Van Camp, John; D'hooghe, Matthias

    2018-05-01

    Curcumin, a natural compound extracted from the rhizomes of Curcuma longa , displays pronounced anticancer properties but lacks good bioavailability and stability. In a previous study, we initiated structure modification of the curcumin scaffold by imination of the labile β-diketone moiety to produce novel β-enaminone derivatives. These compounds showed promising properties for elaborate follow-up studies. In this work, we focused on another class of nitrogen-containing curcuminoids with a similar objective: to address the bioavailability and stability issues and to improve the biological activity of curcumin. This paper thus reports on the synthesis of new pyridine-, indole-, and pyrrole-based curcumin analogues (aza-aromatic curcuminoids) and discusses their water solubility, antioxidant activity, and antiproliferative properties. In addition, multivariate statistics, including hierarchical clustering analysis and principal component analysis, were performed on a broad set of nitrogen-containing curcuminoids. Compared to their respective mother structures, that is, curcumin and bisdemethoxycurcumin, all compounds, and especially the pyridin-3-yl β-enaminone analogues, showed better water solubility profiles. Interestingly, the pyridine-, indole-, and pyrrole-based curcumin derivatives demonstrated improved biological effects in terms of mitochondrial activity impairment and protein content, in addition to comparable or decreased antioxidant properties. Overall, the biologically active N -alkyl β-enaminone aza-aromatic curcuminoids were shown to offer a desirable balance between good solubility and significant bioactivity.

  8. In-depth molecular characterization and biodegradability of water-extractable organic nitrogen in Erhai Lake sediment.

    PubMed

    Zhang, Li; Wang, Shengrui; Yang, Jiachun; Xu, Kechen

    2018-05-08

    Dissolved organic nitrogen (DON) constitutes a significant fraction of the total dissolved nitrogen content of most aquatic systems and is thus a major nitrogen source for bacteria and phytoplankton. The present work applied Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS) to a compound-level analysis of the depth-dependent molecular composition of water-extractable organic nitrogen (WEON) in lake sediment. The study focused on Erhai Lake, China. It was found that a large portion (from 16.33 ± 7.87 to 39.54 ± 5.77%) of the WEON in the lake sediment was reactive under cultivation by algal or bacteria. The WEON in the mid-region of Erhai sediment particularly exhibited a lower bioavailability, having been less affected by the basin environment. The FT-ICR MS results revealed the presence of thousands of compounds in the Erhai Lake sediment samples collected at different depths, with the N-containing compounds accounting for 28.3-34.4% of all the compounds. The WEON molecular weight was also observed to increase with increasing sediment depth. A van Krevelen diagram showed that the lignin-type components were dominant (~ 56.2%) in the sediment WEON, contributing to its stabilization and reducing the risk of sediment nutrient release. The FT-ICR MS results further revealed 204 overlapping formulas of WEON for each core sediment sample, attributable to the presence of refractory components. It was observed that 78.4% of the formulas were within the lignin-like region, suggesting unique allochthonous DON sources. The aliphatic component proportion of all the unique formulas was also found to increase with increasing sediment depth. This indicates that, with the development and evolution of the Erhai Basin, the more labile WEON components were transformed into more stable lignin-like substrates, with a positive effect on the Lake Erhai ecosystem. Graphical abstract ᅟ.

  9. EMMC process for combined removal of organics, nitrogen and an odor producing substance.

    PubMed

    Yang, P Y; Su, R; Kim, S J

    2003-12-01

    In order to improve the process performance regarding the removal of organics, nitrogen, and an odor-causing compound (sulfide) contained in domestic wastewater, an entrapped-mixed-microbial cell (EMMC) with and without humic substances for both fixed and moving carrier reactors and conventional suspended growth culture (i.e. conventional activated sludge process) were investigated simultaneously. Both synthetic (simulated to the organics concentration of general domestic sewage) and actual domestic wastewater were investigated under operational conditions of 12 h of hydraulic retention time (HRT) with 1 h of aeration and 1 h of non-aeration, and 6 h of HRT with continuous aeration, at a room temperature of 25 +/- 2 degrees C. It was found that entrapping humic substances in the EMMC carriers had no impact on the removal of organics, nitrogen, and the odor-producing compound. Additionally, the performance of the EMMC moving carrier system for the removal of these pollutants is similar to that of the EMMC fixed carrier system. In general, the EMMC associated systems which provide high solids retention time achieve a better removal of chemical oxygen demand (COD), nitrogen, and the odor-producing substance than the suspended growth system for both HRTs of 6 h (continuous aeration) and 12 h (1 h of aeration and 1 h of non-aeration). Both the fixed and moving carrier EMMC processes, therefore, have the potential for improvement or replacement of the existing conventional activated sludge process with regard to improving the effluent qualities (such as COD, nitrogen and odor-producing compound) for reuse/disposal.

  10. CYP79D enzymes contribute to jasmonic acid-induced formation of aldoximes and other nitrogenous volatiles in two Erythroxylum species.

    PubMed

    Luck, Katrin; Jirschitzka, Jan; Irmisch, Sandra; Huber, Meret; Gershenzon, Jonathan; Köllner, Tobias G

    2016-10-04

    Amino acid-derived aldoximes and nitriles play important roles in plant defence. They are well-known as precursors for constitutive defence compounds such as cyanogenic glucosides and glucosinolates, but are also released as volatiles after insect feeding. Cytochrome P450 monooxygenases (CYP) of the CYP79 family catalyze the formation of aldoximes from the corresponding amino acids. However, the majority of CYP79s characterized so far are involved in cyanogenic glucoside or glucosinolate biosynthesis and only a few have been reported to be responsible for nitrogenous volatile production. In this study we analysed and compared the jasmonic acid-induced volatile blends of two Erythroxylum species, the cultivated South American crop species E. coca and the African wild species E. fischeri. Both species produced different nitrogenous compounds including aliphatic aldoximes and an aromatic nitrile. Four isolated CYP79 genes (two from each species) were heterologously expressed in yeast and biochemically characterized. CYP79D62 from E. coca and CYP79D61 and CYP79D60 from E. fischeri showed broad substrate specificity in vitro and converted L-phenylalanine, L-isoleucine, L-leucine, L-tryptophan, and L-tyrosine into the respective aldoximes. In contrast, recombinant CYP79D63 from E. coca exclusively accepted L-tryptophan as substrate. Quantitative real-time PCR revealed that CYP79D60, CYP79D61, and CYP79D62 were significantly upregulated in jasmonic acid-treated Erythroxylum leaves. The kinetic parameters of the enzymes expressed in vitro coupled with the expression patterns of the corresponding genes and the accumulation and emission of (E/Z)-phenylacetaldoxime, (E/Z)-indole-3-acetaldoxime, (E/Z)-3-methylbutyraldoxime, and (E/Z)-2-methylbutyraldoxime in jasmonic acid-treated leaves suggest that CYP79D60, CYP79D61, and CYP79D62 accept L-phenylalanine, L-leucine, L-isoleucine, and L-tryptophan as substrates in vivo and contribute to the production of volatile and semi-volatile nitrogenous defence compounds in E. coca and E. fischeri.

  11. Utilization of urea, ammonia, nitrite, and nitrate by crop plants in a Controlled Ecological Life Support System (CELSS)

    NASA Technical Reports Server (NTRS)

    Huffaker, R. C.; Rains, D. W.; Qualset, C. O.

    1982-01-01

    The utilization of nitrogen compounds by crop plants is studied. The selection of crop varieties for efficient production using urea, ammonia, nitrite, and nitrate, and the assimilation of mixed nitrogen sources by cereal leaves and roots are discussed.

  12. 75 FR 47218 - Approval and Promulgation of Implementation Plans and Designation of Areas for Air Quality...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-08-05

    ... Kentucky, through the Kentucky Energy and Environment Cabinet, Division for Air Quality (DAQ), to... (MVEBs) for nitrogen oxides (NO X ) and volatile organic compounds (VOC) for Northern Kentucky. This... control, Incorporation by reference, Nitrogen dioxide, Ozone, Intergovernmental relations, and Volatile...

  13. New thymine-based derivative of nitrogen mustards.

    PubMed

    Boëns, Benjamin; Teste, Karine; Hadj-Bouazza, Amel; Ismaili, Jihane; Zerrouki, Rachida

    2012-01-01

    This work deals with the synthesis of a new nitrogen mustard derivative based on thymine. To introduce the bis(2-chloroethyl)amine group to position 4 of the pyrimidine base, many strategies were explored and the desired compound was finally obtained, thanks to a synthetic pathway in five steps.

  14. Long-term trends in sulfur and reactive nitrogen deposition across the Northern Hemisphere and United States

    EPA Science Inventory

    A detailed understanding of the distribution and fate of atmospheric sulfur (SOx) and reactive nitrogen compounds (NOy and NHx) is desirable given their role in determining tropospheric acidic substances and particulate matter budgets and potential nutrient loading effects in sen...

  15. Anti-flammable properties of capable phosphorus-nitrogen containing triazine derivatives on cotton

    USDA-ARS?s Scientific Manuscript database

    Most of new phosphorus-nitrogen containing compounds were prepared by organic reactions of cyanuric chloride and phosphonates. They were characterized by analytical tools such as proton (1H), carbon (13C), and phosphorus (31P) nuclear magnetic resonance (NMR) spectroscopy and elemental analysis (EA)...

  16. Low-energy N+ ion irradiation induced synthesis of nitrogenous compound from solid organic sodium salts

    NASA Astrophysics Data System (ADS)

    Wang, Xiangqin; Yu, Zengliang

    2003-08-01

    In this paper, samples of solid organic sodium salts (sodium formate, sodium acetate and sodium benzoate) were irradiated by low-energy N+ ions. The induced damage was detected by infrared (FT-IR). It is shown that a new cyano group (-CN) and amino group (-NH2) were formed in the irradiated sodium carbroxylic sample with N+ ion irradiation. The experimental results examined the effect of N+ ion irradiation by reacting with sodium salt molecules, and presented a new way for the synthesis of nitrogenous compound by low-energy ion irradiation.

  17. [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.

  18. TRANC - a novel fast-response converter to measure total reactive atmospheric nitrogen

    NASA Astrophysics Data System (ADS)

    Marx, O.; Brümmer, C.; Ammann, C.; Wolff, V.; Freibauer, A.

    2011-12-01

    The input and loss of plant available nitrogen (N) from/to the atmosphere can be an important factor for the productivity of ecosystems and thus for its carbon and greenhouse gas exchange. We present a novel converter for the measurement of total reactive nitrogen (TRANC: Total Reactive Atmospheric Nitrogen Converter), which offers the opportunity to quantify the sum of all airborne reactive nitrogen (Nr) compounds in high time resolution. The basic concept of the TRANC is the full conversion of total Nr to nitrogen monoxide (NO) within two reaction steps. Initially, reduced N compounds are being oxidised, and oxidised N compounds are thermally converted to lower oxidation states. Particulate N is being sublimated and oxidised or reduced afterwards. In a second step, remaining higher N oxides or those originated in the first step are catalytically converted to NO with carbon monoxide used as reduction gas. The converter is combined with a fast response chemiluminescence detector (CLD) for NO analysis and its performance was tested for the most relevant gaseous and particulate Nr species under both laboratory and field conditions. Recovery rates during laboratory tests for NH3 and NO2 were found to be 95 and 99%, respectively, and 97% when the two gases were combined. In-field longterm stability over an 11-month period was approved by a value of 91% for NO2. Effective conversion was also found for ammonium and nitrate containing particles. The recovery rate of total ambient Nr was tested against the sum of individual measurements of NH3, HNO3, HONO, NH4+, NO3-, and NOx using a combination of different well-established devices. The results show that the TRANC-CLD system precisely captures fluctuations in Nr concentrations and also matches the sum of all Nr compounds measured by the different single techniques. The TRANC features a specific design with very short distance between the sample air inlet and the place where the thermal and catalytic conversions to NO occur. This assures a short residence time of the sample air inside the instrument, and minimises wall sorption problems of water soluble compounds. The fast response time (half-value periods of 0.30 s were found during concentration step changes) and high accuracy in capturing the dominant Nr species enables the converter to be used in an eddy covariance setup. Although a source attribution of specific Nr compounds is not possible, the TRANC is a new reliable tool for permanent measurements of the net Nr flux between ecosystem and atmosphere at a relatively low maintenance and reasonable cost level allowing for diurnal, seasonal and annual investigations.

  19. Influence of a reaction medium on the oxidation of aromatic nitrogen-containing compounds by peroxyacids

    NASA Astrophysics Data System (ADS)

    Dutka, V. S.; Matsyuk, N. V.; Dutka, Yu. V.

    2011-01-01

    The influence of different solvents on the oxidation reaction rate of pyridine (Py), quinoline (QN), acridine (AN), α-oxyquinoline (OQN) and α-picolinic acid (APA) by peroxydecanoic acid (PDA) was studied. It was found that the oxidation rate grows in the series Py < QN < AN, and the rate of the oxidation reaction of compounds containing a substituent in the α position from a reactive center is significantly lower than for unsubstituted analogues. The effective energies of activation of the oxidation reaction were found. It was shown that in the first stage, the reaction mechanism includes the rapid formation of an intermediate complex nitrogen-containing compound, peroxyacid, which forms products upon decomposing in the second stage. A kinetic equation that describes the studied process is offered. The constants of equilibrium of the intermediate complex formation ( K eq) and its decomposition constant ( k 2) in acetone and benzene were calculated. It was shown that the nature of the solvent influences the numerical values of both K p and k 2. It was established that introduction of acetic acid (which is able to form compounds with Py) into the reaction medium slows the rate of the oxidation process drastically. Correlation equations linking the polarity, polarizability, electrophilicity, and basicity of solvents with the constant of the PDA oxidation reaction rate for Py were found. It was concluded that the basicity and polarity of the solvent have a decisive influence on the oxidation reaction rate, while the polarizability and electrophilicity of the reaction medium do not influence the oxidation reaction rate.

  20. Numerical and Experimental Study on the Residual Stresses in the Nitrided Steel

    NASA Astrophysics Data System (ADS)

    Song, X.; Zhang, Zhi-Qian; Narayanaswamy, S.; Huang, Y. Z.; Zarinejad, M.

    2016-09-01

    In the present work, residual stresses distribution in the gas nitrided AISI 4140 sample has been studied using finite element (FE) simulation. The nitrogen concentration profile is obtained from the diffusion-controlled compound layer growth model, and nitrogen concentration controls the material volume change through phase transformation and lattice interstitials which results in residual stresses. Such model is validated through residual stress measurement technique—micro-ring-core method, which is applied to the nitriding process to obtain the residual stresses profiles in both the compound and diffusion layer. The numerical and experimental results are in good agreement with each other; they both indicate significant stress variation in the compound layer, which was not captured in previous research works due to the resolution limit of the traditional methods.

  1. Structural characteristics of novel symmetrical diaryl derivatives with nitrogenated functions. Requirements for cytotoxic activity.

    PubMed

    Font, María; Ardaiz, Elena; Cordeu, Lucia; Cubedo, Elena; García-Foncillas, Jesús; Sanmartin, Carmen; Palop, Juan-Antonio

    2006-03-15

    In an attempt to discover the essential features that would allow us to explain the differences in cytotoxic activity shown by a series of symmetrical diaryl derivatives with nitrogenated functions, we have studied by molecular modelling techniques the variation in Log P and conformational behaviour, in terms of structural modifications. The Log P data--although they provide few clues concerning the observed variability in activity--suggest that an initial separation of active and inactive compounds is possible based on this parameter. The subsequent study of the conformational behaviour of the compounds, selected according to their Log P values, showed that the active compounds preferentially display an extended conformation and inactive ones are associated with a certain type of folding, with a triangular-type conformation adopted in these cases.

  2. Occurrence of organic wastewater contaminants, pharmaceuticals, and personal care products in selected water supplies, Cape Cod, Massachusetts, June 2004

    USGS Publications Warehouse

    Zimmerman, Marc J.

    2005-01-01

    In June 2004, the U.S. Geological Survey, in cooperation with the Barnstable County Department of Health and Environment, sampled water from 14 wastewater sources and drinking-water supplies on Cape Cod, Massachusetts, for the presence of organic wastewater contaminants, pharmaceuticals, and personal care products. The geographic distribution of sampling locations does not represent the distribution of drinking-water supplies on Cape Cod. The environmental presence of the analyte compounds is mostly unregulated; many of the compounds are suspected of having adverse ecological and human health effects. Of the 85 different organic analyte compounds, 43 were detected, with 13 detected in low concentrations (less than 1 microgram per liter) from drinking-water supplies thought to be affected by wastewater because of previously detected high nitrate concentrations. (Phenol and d-limonene, detected in equipment blanks at unacceptably high concentrations, are not included in counts of detections in this report.) Compounds detected in the drinking-water supplies included the solvent, tetrachloroethylene; the analgesic, acetaminophen; the antibiotic, sulfamethoxazole; and the antidepressant, carbamazapine. Nitrate nitrogen, an indicator of wastewater, was detected in water supplies in concentrations ranging from 0.2 to 8.8 milligrams per liter.

  3. 77 FR 60626 - Approval and Promulgation of Air Quality Implementation Plans; Virginia; The 2002 Base Year...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-10-04

    ... nitrogen oxides (NO X ), volatile organic compounds (VOCs), PM 2.5 , coarse particles (PM 10 ), ammonia (NH... X ), volatile organic compounds (VOCs), PM 2.5 , coarse particles (PM 10 ), ammonia (NH 3 ), and...

  4. Interrelated responses of tomato plants and the leaf miner Tuta absoluta to nitrogen supply.

    PubMed

    Larbat, R; Adamowicz, S; Robin, C; Han, P; Desneux, N; Le Bot, J

    2016-05-01

    Plant-insect interactions are strongly modified by environmental factors. This study evaluates the influence of nitrogen fertilisation on the tomato (Solanum lycopersicum L.) cv. Santa clara and the leafminer (Tuta absoluta (Meyrick), Lepidoptera: Gelechiidae). Greenhouse-grown tomato plants were fed hydroponically on a complete nutrient solution containing either a high nitrogen concentration (HN) sustaining maximum growth or a low nitrogen concentration (LN) limiting plant growth. Insect-free plants were compared with plants attacked by T. absoluta. Seven and 14 days after artificial oviposition leading to efficacious hatching and larvae development, we measured total carbon, nitrogen and soluble protein as well as defence compounds (phenolics, glycoalkaloids, polyphenol oxidase activity) in the HN versus LN plants. Only in the HN treatment did T. absoluta infestation slightly impair leaf growth and induce polyphenol oxidase (PPO) activity in the foliage. Neither the concentration of phenolic compounds and proteins nor the distribution of nitrogen within the plant was affected by T. absoluta infestation. In contrast, LN nutrition impaired T. absoluta-induced PPO activity. It decreased protein and total nitrogen concentration of plant organs and enhanced the accumulation of constitutive phenolics and tomatine. Moreover, LN nutrition impaired T. absoluta development by notably decreasing pupal weight and lengthening the development period from egg to adult. Adjusting the level of nitrogen nutrition may thus be a means of altering the life cycle of T. absoluta. This study provides a comprehensive dataset concerning interrelated responses of tomato plants and T. absoluta to nitrogen nutrition. © 2015 German Botanical Society and The Royal Botanical Society of the Netherlands.

  5. Biotransformation of nitrogen- and sulfur-containing pollutants during coking wastewater treatment: Correspondence of performance to microbial community functional structure.

    PubMed

    Joshi, Dev Raj; Zhang, Yu; Gao, Yinxin; Liu, Yuan; Yang, Min

    2017-09-15

    Although coking wastewater is generally considered to contain high concentration of nitrogen- and sulfur-containing pollutants, the biotransformation processes of these compounds have not been well understood. Herein, a high throughput functional gene array (GeoChip 5.0) in combination with Illumina MiSeq sequencing of the 16S rRNA gene were used to identify microbial functional traits and their role in biotransformation of nitrogen- and sulfur-containing compounds in a bench-scale aerobic coking wastewater treatment system operated for 488 days. Biotransformation of nitrogen and sulfur-containing pollutants deteriorated when pH of the bioreactor was increased to >8.0, and the microbial community functional structure was significantly associated with pH (Mantels test, P < 0.05). The release of ammonia nitrogen and sulfate was correlated with both the taxonomic and functional microbial community structure (P < 0.05). Considering the abundance and correlation with the release of ammonia nitrogen and sulfate, aromatic dioxygenases (e.g. xylXY, nagG), nitrilases (e.g. nhh, nitrilase), dibenzothiophene oxidase (DbtAc), and thiocyanate hydrolase (scnABC) were important functional genes for biotransformation of nitrogen- and sulfur-containing pollutants. Functional characterization of taxa and network analysis suggested that Burkholderiales, Actinomycetales, Rhizobiales, Pseudomonadales, and Hydrogenophiliales (Thiobacillus) were key functional taxa. Variance partitioning analysis showed that pH and influent ammonia nitrogen jointly explained 25.9% and 35.5% of variation in organic pollutant degrading genes and microbial community structure, respectively. This study revealed a linkage between microbial community functional structure and the likely biotransformation of nitrogen- and sulfur-containing pollutants, along with a suitable range of pH (7.0-7.5) for stability of the biological system treating coking wastewater. Copyright © 2017 Elsevier Ltd. All rights reserved.

  6. Investigation of atmospheric pressure capillary non-thermal plasmas and their applications to the degradation of volatile organic compounds

    NASA Astrophysics Data System (ADS)

    Yin, Shu-Min

    Atmospheric pressure capillary non-thermal plasma (AP-CNTP) has been investigated as a potential technology far the removal of volatile organic compounds (VOCs) in Advanced Life Support Systems (ALS). AP-CNTP is a destructive technology far the removal of VOCs from air streams by active plasma species, such as electrons, ions, and excited molecules. Complete VOC destruction ideally results in the formation of water, carbon dioxide (CO2), and other by-product's may also form, including ozone (O3), nitrous oxide (N2O), nitrogen dioxide (NO2), and decomposed hydrocarbons. Several organic compounds, such as BTEX, ethylene, n-heptane, isooctane, methanol and NH3, were tested in an AP-CNTP system. Parametric experiments were carried out by varying plasma discharge power, flowrates, and initial concentrations. The degradation efficiency varied depending on the chemical nature of the compounds. A plasmochemical kinetic model was derived for toluene, ethylbenzene, and m-xylene and n-heptane.

  7. The role of aromatic precursors in the formation of haloacetamides by chloramination of dissolved organic matter.

    PubMed

    Le Roux, Julien; Nihemaiti, Maolida; Croué, Jean-Philippe

    2016-01-01

    Water treatment utilities are diversifying their water sources and often rely on waters enriched in nitrogen-containing compounds (e.g., ammonia, organic nitrogen such as amino acids). The disinfection of waters exhibiting high levels of nitrogen has been associated with the formation of nitrogenous disinfection byproducts (N-DBPs) such as haloacetonitriles (HANs) and haloacetamides (HAcAms). While the potential precursors of HANs have been extensively studied, only few investigations are available regarding the nature of HAcAm precursors. Previous research has suggested that HAcAms are hydrolysis products of HANs. Nevertheless, it has been recently suggested that HAcAms can be formed independently, especially during chloramination of humic substances. When used as a disinfectant, monochloramine can also be a source of nitrogen for N-DBPs. This study investigated the role of aromatic organic matter in the formation of N-DBPs (HAcAms and HANs) upon chloramination. Formation kinetics were performed from various fractions of organic matter isolated from surface waters or treated wastewater effluents. Experiments were conducted with (15)N-labeled monochloramine ((15)NH2Cl) to trace the origin of nitrogen. N-DBP formation showed a two-step profile: (1) a rapid formation following second-order reaction kinetics and incorporating nitrogen atom originating from the organic matrix (e.g., amine groups); and (2) a slower and linear increase correlated with exposure to chloramines, incorporating inorganic nitrogen ((15)N) from (15)NH2Cl into aromatic moieties. Organic matter isolates showing high aromatic character (i.e., high SUVA) exhibited high reactivity characterized by a major incorporation of (15)N in N-DBPs. A significantly lower incorporation was observed for low-aromatic-content organic matter. (15)N-DCAcAm and (15)N-DCAN formations exhibited a linear correlation, suggesting a similar behavior of (15)N incorporation as SUVA increases. Chloramination of aromatic model compounds (i.e., phenol and resorcinol) showed higher HAcAm and HAN formation potentials than nitrogenous precursors (i.e., amino acids) usually considered as main precursors of these N-DBPs. These results demonstrate the importance of aromatic organic compounds in the formation of N-DBPs, which is of significant importance for water treatment facilities using chloramines as final disinfectant. Copyright © 2015 Elsevier Ltd. All rights reserved.

  8. Enzyme activity in terrestrial soil in relation to exploration of the Martian surface

    NASA Technical Reports Server (NTRS)

    Ardakani, M. S.; Mclaren, A. D.; Pukite, A. H.

    1972-01-01

    An exploration was made of enzyme activities in soil, including abundance, persistence and localization of these activities. An attempt was made to develop procedures for the detection and assaying of enzymes in soils suitable for presumptive tests for life in planetary soils. A suitable extraction procedure for soil enzymes was developed and measurements were made of activities in extracts in order to study how urease is complexed in soil organic matter. Mathematical models were developed, based on enzyme action and microbial growth in soil, for rates of oxidation of nitrogen as nitrogen compounds are moved downward in soil by water flow. These biogeochemical models should be applicable to any percolating system, with suitable modification for special features, such as oxygen concetrations, and types of hydrodynamic flow.

  9. Stable and Inert Cobalt Catalysts for Highly Selective and Practical Hydrogenation of C≡N and C═O Bonds.

    PubMed

    Chen, Feng; Topf, Christoph; Radnik, Jörg; Kreyenschulte, Carsten; Lund, Henrik; Schneider, Matthias; Surkus, Annette-Enrica; He, Lin; Junge, Kathrin; Beller, Matthias

    2016-07-20

    Novel heterogeneous cobalt-based catalysts have been prepared by pyrolysis of cobalt complexes with nitrogen ligands on different inorganic supports. The activity and selectivity of the resulting materials in the hydrogenation of nitriles and carbonyl compounds is strongly influenced by the modification of the support and the nitrogen-containing ligand. The optimal catalyst system ([Co(OAc)2/Phen@α-Al2O3]-800 = Cat. E) allows for efficient reduction of both aromatic and aliphatic nitriles including industrially relevant dinitriles to primary amines under mild conditions. The generality and practicability of this system is further demonstrated in the hydrogenation of diverse aliphatic, aromatic, and heterocyclic ketones as well as aldehydes, which are readily reduced to the corresponding alcohols.

  10. Radiolysis and Photolysis of Icy Satellite Surfaces: Experiments and Theory

    NASA Technical Reports Server (NTRS)

    Cassidy, T.; Coll, P.; Raulin, F.; Carlson, R. W.; Hand, K. P.; Johnson, R. E.; Loeffler, M. J.; Baragiola, R. A.

    2010-01-01

    The transport and exchange of material between bodies in the outer solar system is often facilitated by their exposure to ionizing radiation. With this in mind we review the effects of energetic ions, electrons and UV photons on materials present in the outer solar system. We consider radiolysis, photolysis, and sputtering of low temperature solids. Radiolysis and photolysis are the chemistry that follows the bond breaking and ionization produced by incident radiation, producing, e.g., O2 and H2 from irradiated H2O ice. Sputtering is the ejection of molecules by incident radiation. Both processes are particularly effective on ices in the outer solar system. Materials reviewed include H2O ice, sulfur-containing compounds (such as S02 and S8), carboncontajning compounds (such as CH4), nitrogen-containing compounds (such as NH3 and N2), and mixtures of those compounds. We also review the effects of ionizing radiation on a mixture of N2 and CH4 gases, as appropriate to Titan's upper atmosphere, where radiolysis and photolysis produce complex organic compounds (tholins).

  11. Chitin: 'Forgotten' Source of Nitrogen: From Modern Chitin to Thermally Mature Kerogen: Lessons from Nitrogen Isotope Ratios

    USGS Publications Warehouse

    Schimmelmann, A.; Wintsch, R.P.; Lewan, M.D.; DeNiro, M.J.

    1998-01-01

    Chitinous biomass represents a major pool of organic nitrogen in living biota and is likely to have contributed some of the fossil organic nitrogen in kerogen. We review the nitrogen isotope biogeochemistry of chitin and present preliminary results suggesting interaction between kerogen and ammonium during thermal maturation. Modern arthropod chitin may shift its nitrogen isotope ratio by a few per mil depending on the chemical method of chitin preparation, mostly because N-containing non-amino-sugar components in chemically complex chitin cannot be removed quantitatively. Acid hydrolysis of chemically complex chitin and subsequent ion-chromatographic purification of the "deacetylated chitin-monomer" D-glucosamine (in hydrochloride form) provides a chemically well-defined, pure amino-sugar substrate for reproducible, high-precision determination of ??15N values in chitin. ??15N values of chitin exhibited a variability of about one per mil within an individual's exoskeleton. The nitrogen isotope ratio differed between old and new exoskeletons by up to 4 per mil. A strong dietary influence on the ??15N value of chitin is indicated by the observation of increasing ??15N values of chitin from marine crustaceans with increasing trophic level. Partial biodegradation of exoskeletons does not significantly influence ??15N values of remaining, chemically preserved amino sugar in chitin. Diagenesis and increasing thermal maturity of sedimentary organic matter, including chitin-derived nitrogen-rich moieties, result in humic compounds much different from chitin and may significantly change bulk ??15N values. Hydrous pyrolysis of immature source rocks at 330??C in contact with 15N-enriched NH4Cl, under conditions of artificial oil generation, demonstrates the abiogenic incorporation of inorganic nitrogen into carbon-bound nitrogen in kerogen. Not all organic nitrogen in natural, thermally mature kerogen is therefore necessarily derived from original organic matter, but may partly result from reaction with ammonium-containing pore waters.

  12. 77 FR 73544 - Approval and Promulgation of Air Quality Implementation Plans; West Virginia; The 2002 Base Year...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-12-11

    ... nitrogen oxides (NO X ), volatile organic compounds (VOCs), PM 2.5 , coarse particles (PM 10 ), ammonia (NH... oxides (NO X ), volatile organic compounds (VOCs), PM 2.5 , coarse particles (PM 10 ), ammonia (NH 3...

  13. Alkynylation of heterocyclic compounds using hypervalent iodine reagent.

    PubMed

    Kamlar, M; Císařová, I; Veselý, J

    2015-03-14

    The alkynylation of various nitrogen- and/or sulphur-containing heterocyclic compounds using hypervalent iodine TMS-EBX by utilization of tertiary amines under mild conditions is described. The developed metal-free methodology furnishes the corresponding alkynylated heterocycles bearing quaternary carbon in high yields.

  14. 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 ...

  15. Methylamine as a nitrogen source for microorganisms from a coastal marine environment.

    PubMed

    Taubert, Martin; Grob, Carolina; Howat, Alexandra M; Burns, Oliver J; Pratscher, Jennifer; Jehmlich, Nico; von Bergen, Martin; Richnow, Hans H; Chen, Yin; Murrell, J Colin

    2017-06-01

    Nitrogen is a key limiting resource for biomass production in the marine environment. Methylated amines, released from the degradation of osmolytes, could provide a nitrogen source for marine microbes. Thus far, studies in aquatic habitats on the utilization of methylamine, the simplest methylated amine, have mainly focussed on the fate of the carbon from this compound. Various groups of methylotrophs, microorganisms that can grow on one-carbon compounds, use methylamine as a carbon source. Non-methylotrophic microorganisms may also utilize methylamine as a nitrogen source, but little is known about their diversity, especially in the marine environment. In this proof-of-concept study, stable isotope probing (SIP) was used to identify microorganisms from a coastal environment that assimilate nitrogen from methylamine. SIP experiments using 15 N methylamine combined with metagenomics and metaproteomics facilitated identification of active methylamine-utilizing Alpha- and Gammaproteobacteria. The draft genomes of two methylamine utilizers were obtained and their metabolism with respect to methylamine was examined. Both bacteria identified in these SIP experiments used the γ-glutamyl-methylamide pathway, found in both methylotrophs and non-methylotrophs, to metabolize methylamine. The utilization of 15 N methylamine also led to the release of 15 N ammonium that was used as nitrogen source by other microorganisms not directly using methylamine. © 2017 Society for Applied Microbiology and John Wiley & Sons Ltd.

  16. Atmosphere-Forest Exchange: Important Questions Regarding the Atmosphere's Role in the Delivery of Nutrient Nitrogen and Impacts on Nitrogen and Carbon Cycling

    NASA Astrophysics Data System (ADS)

    Carroll, M.; Shepson, P. B.; Bertman, S. B.; Sparks, J. P.; Holland, E. A.

    2002-12-01

    Atmosphere-Forest Exchange: Important Questions Regarding the Atmosphere's Role in the Delivery of Nutrient Nitrogen and Impacts on Nitrogen and Carbon Cycling Atmospheric composition and chemistry directly affect ecosystem nitrogen cycling and indirectly affect ecosystem carbon cycling and storage. Current understanding of atmosphere-forest nitrogen exchange and subsequent impacts is based almost exclusively on nitrogen deposition data obtained from networks using buckets placed in open areas, studies involving inorganic nitrogen, frequently with enhanced N deposition inputs applied only to soils, and that ignore multiple stresses (e.g., the combined effects of aerosols, ozone exposure, elevated CO2, and drought). Current models of nitrogen cycling treat deposited nitrogen (e.g., HNO3 and NO3-) as a permanent sink whereas data appear to indicate that photolytic and heterogeneous chemical processes occurring on surfaces and in dew can result in the re-evolution of gaseous species such as NO and HONO. Similarly, the direct uptake of gaseous nitrogen compounds by foliage has been neglected, compromising conclusions drawn from deposition experiments and ignoring a mechanism that may significantly affect nitrogen cycling and carbon storage, one that may become more significant with future atmospheric and climate change. We hypothesize that the atmosphere plays a significant role in the delivery of nutrient nitrogen to the N-limited mixed hardwood forest at the PROPHET research site at the University of Michigan Biological Station. We assert that a complete understanding of atmosphere- biosphere interactions and feedbacks is required to develop a predictive capability regarding forest response to increasing atmospheric CO2, reactive nitrogen, oxidants, and aerosols, increasing nitrogen and acidic deposition, and anticipated climate change. We further assert that conclusions drawn from studies that are limited to inorganic nitrogen, fertilization of soils, and/or that neglect the role of the canopy (in N uptake and/or remobilization) may not produce a complete understanding of N and C cycling in terrestrial ecosystems, including atmosphere-biosphere interactions and feedbacks. Here, as part of a new PROPHET focus on Biosphere Exchange of Atmospheric Carbon and Odd Nitrogen (BEACON), we identify a number of issues associated with nitrogen limited forest ecosystems and nitrogen saturation and important science questions that require collaborative studies involving the atmospheric and biospheric science communities.

  17. Actinide halide complexes

    DOEpatents

    Avens, Larry R.; Zwick, Bill D.; Sattelberger, Alfred P.; Clark, David L.; Watkin, John G.

    1992-01-01

    A compound of the formula MX.sub.n L.sub.m wherein M is a metal atom selected from the group consisting of thorium, plutonium, neptunium or americium, X is a halide atom, n is an integer selected from the group of three or four, L is a coordinating ligand selected from the group consisting of aprotic Lewis bases having an oxygen-, nitrogen-, sulfur-, or phosphorus-donor, and m is an integer selected from the group of three or four for monodentate ligands or is the integer two for bidentate ligands, where the sum of n+m equals seven or eight for monodentate ligands or five or six for bidentate ligands, a compound of the formula MX.sub.n wherein M, X, and n are as previously defined, and a process of preparing such actinide metal compounds including admixing the actinide metal in an aprotic Lewis base as a coordinating solvent in the presence of a halogen-containing oxidant, are provided.

  18. Soluble Nutrient and Trace Metal Fluxes from Aerosol Dry Deposition to Elkhorn Slough, CA

    NASA Astrophysics Data System (ADS)

    Gray, E. T.; Paytan, A.; Haskins, J.

    2009-12-01

    Atmospheric deposition has been widely recognized as a source of pollutants and nutrients to coastal ecosystems. Specifically, deposition includes nitrogen compounds, sulfur compounds, mercury, pesticides, phosphate, trace metals and other toxic compounds that can travel great distances in aerosols. These components can come from both natural (volcanoes, mineral dust, forest fires) and anthropogenic (fossil fuels, chemical byproducts, incineration of waste) sources. These pollutants may affect ecosystem health and water quality with environmental impacts such as eutrophication, contaminated fish and harmful algal blooms. In this study we focus on dry deposition to Elkhorn Slough, California. Size fractionated aerosol samples (PM 2.5 and PM 10) collected continuously over a seven day period using a cascade impactor are used along with a deposition model to determine the soluble nutrient and trace metal fluxes on the Elkhorn Slough ecosystem. Atmospheric deposition inputs will be compared to other sources and their potential impact evaluated.

  19. Actinide halide complexes

    DOEpatents

    Avens, L.R.; Zwick, B.D.; Sattelberger, A.P.; Clark, D.L.; Watkin, J.G.

    1992-11-24

    A compound is described of the formula MX[sub n]L[sub m] wherein M is a metal atom selected from the group consisting of thorium, plutonium, neptunium or americium, X is a halide atom, n is an integer selected from the group of three or four, L is a coordinating ligand selected from the group consisting of aprotic Lewis bases having an oxygen-, nitrogen-, sulfur-, or phosphorus-donor, and m is an integer selected from the group of three or four for monodentate ligands or is the integer two for bidentate ligands, where the sum of n+m equals seven or eight for monodentate ligands or five or six for bidentate ligands. A compound of the formula MX[sub n] wherein M, X, and n are as previously defined, and a process of preparing such actinide metal compounds are described including admixing the actinide metal in an aprotic Lewis base as a coordinating solvent in the presence of a halogen-containing oxidant.

  20. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Larimer, Frank W; Chain, Patrick S. G.; Hauser, Loren John

    Rhodopseudomonas palustris is among the most metabolically versatile bacteria known. It uses light, inorganic compounds, or organic compounds, for energy. It acquires carbon from many types of green plant-derived compounds or by carbon dioxide fixation, and it fixes nitrogen. Here we describe the genome sequence of R. palustris, which consists of a 5,459,213-base-pair (bp) circular chromosome with 4,836 predicted genes and a plasmid of 8,427 bp. The sequence reveals genes that confer a remarkably large number of options within a given type of metabolism, including three nitrogenases, five benzene ring cleavage pathways and four light harvesting 2 systems. R. palustrismore » encodes 63 signal transduction histidine kinases and 79 response regulator receiver domains. Almost 15% of the genome is devoted to transport. This genome sequence is a starting point to use R. palustris as a model to explore how organisms integrate metabolic modules in response to environmental perturbations.« less

  1. The Chemistry of Nitroxyl-Releasing Compounds

    PubMed Central

    DuMond, Jenna F.

    2011-01-01

    Abstract Nitroxyl (HNO) demonstrates a diverse and unique biological profile compared to nitric oxide, a redox-related compound. Although numerous studies support the use of HNO as a therapeutic agent, the inherent chemical reactivity of HNO requires the use of donor molecules. Two general chemical strategies currently exist for HNO generation from nitrogen-containing molecules: (i) the disproportionation of hydroxylamine derivatives containing good leaving groups attached to the nitrogen atom and (ii) the decomposition of nitroso compounds (X-N=O, where X represents a good leaving group). This review summarizes the synthesis and structure, the HNO-releasing mechanisms, kinetics and by-product formation, and alternative reactions of six major groups of HNO donors: Angeli's salt, Piloty's acid and its derivatives, cyanamide, diazenium diolate-derived compounds, acyl nitroso compounds, and acyloxy nitroso compounds. A large body of work exists defining these six groups of HNO donors and the overall chemistry of each donor requires consideration in light of its ability to produce HNO. The increasing interest in HNO biology and the potential of HNO-based therapeutics presents exciting opportunities to further develop HNO donors as both research tools and potential treatments. Antioxid. Redox Signal. 14, 1637–1648. PMID:21235345

  2. Highly dynamic cellular-level response of symbiotic coral to a sudden increase in environmental nitrogen.

    PubMed

    Kopp, C; Pernice, M; Domart-Coulon, I; Djediat, C; Spangenberg, J E; Alexander, D T L; Hignette, M; Meziane, T; Meibom, A

    2013-05-14

    Metabolic interactions with endosymbiotic photosynthetic dinoflagellate Symbiodinium spp. are fundamental to reef-building corals (Scleractinia) thriving in nutrient-poor tropical seas. Yet, detailed understanding at the single-cell level of nutrient assimilation, translocation, and utilization within this fundamental symbiosis is lacking. Using pulse-chase (15)N labeling and quantitative ion microprobe isotopic imaging (NanoSIMS; nanoscale secondary-ion mass spectrometry), we visualized these dynamic processes in tissues of the symbiotic coral Pocillopora damicornis at the subcellular level. Assimilation of ammonium, nitrate, and aspartic acid resulted in rapid incorporation of nitrogen into uric acid crystals (after ~45 min), forming temporary N storage sites within the dinoflagellate endosymbionts. Subsequent intracellular remobilization of this metabolite was accompanied by translocation of nitrogenous compounds to the coral host, starting at ~6 h. Within the coral tissue, nitrogen is utilized in specific cellular compartments in all four epithelia, including mucus chambers, Golgi bodies, and vesicles in calicoblastic cells. Our study shows how nitrogen-limited symbiotic corals take advantage of sudden changes in nitrogen availability; this opens new perspectives for functional studies of nutrient storage and remobilization in microbial symbioses in changing reef environments. The methodology applied, combining transmission electron microscopy with nanoscale secondary-ion mass spectrometry (NanoSIMS) imaging of coral tissue labeled with stable isotope tracers, allows quantification and submicrometric localization of metabolic fluxes in an intact symbiosis. This study opens the way for investigations of physiological adaptations of symbiotic systems to nutrient availability and for increasing knowledge of global nitrogen and carbon biogeochemical cycling.

  3. Reactive Uptake of Ammonia to Secondary Organic Aerosols: Kinetics of Organonitrogen Formation

    NASA Astrophysics Data System (ADS)

    Liu, Yongchun; Liggio, John; Staebler, Ralf; Li, Shao-Meng

    2015-04-01

    Organonitrogen compounds originating from the heterogeneous uptake of NH3 or amines by secondary organic aerosol (SOA) has received significant attention recently. This is primarily due to its potential contribution to brown carbon (BrC), which can absorb solar radiation and affect climate. In addition, particle phase Organonitrogen species may represent a means of altering regional nitrogen cycles and/or nitrogen deposition patterns though the sequestering of ambient ammonia which is ultimately deposited downwind. Several reduced nitrogen forming heterogeneous reactions have previously been proposed, including Schiff base and/or Mannich reactions between NH3, ammonium salts or amines and organic carbonyl functional groups in particles. In order to assess and model the possible impact of Schiff base, Mannich or other N-forming reactions (via NH3) on the radiative forcing ability of ambient SOA and/or its impact on N-deposition, the kinetics of such heterogeneous reactions are required, and yet remain largely unknown. In the current study, the uptake kinetics of NH3 to form organonitrogen compounds in SOA derived from the ozonolysis of α-pinene and the OH oxidation of m-xylene is reported for the first time from experiments performed in a 9 m3 smog chamber equipped with a High Resolution Time-of-Flight Aerosol Mass Spectrometer. The results demonstrate that particle bound organonitrogen compounds are mainly formed by NH3 uptake onto newly formed SOA (~1 hr), but relatively little onto more aged SOA. The uptake coefficients of NH3 to form organonitrogen compounds (between 0-150 min) are on the order of 10-4-10-3 and are prominently dependent upon particle acidity. Following 6 hours of reaction, the total organonitrogen mass contributed up to 10.0±1.5 wt% and 31.5±4.4 wt% to the total SOA mass from the ozonolysis of α-pinene and OH oxidation of m-xylene. The influence of VOC precursors, seed particle acidity and gaseous NH3 concentration on the obtained uptake coefficients is described. The implications of the kinetics on atmospheric BrC and N-deposition are also discussed.

  4. Quantification of Lightning-induced Nitrogen Oxides in CMAQ and the Assessment of its impact on Ground-level Air Quality

    EPA Science Inventory

    Lightning-induced nitrogen oxides (LNOX), in the presence of sunlight, volatile organic compounds and water, can be a relatively large but uncertain source for ozone (O3) and hydroxyl radical (OH) in the atmosphere. Using lightning flash data from the National Lightning Detection...

  5. 78 FR 34911 - Approval and Promulgation of Air Quality Implementation Plans; Maryland; Low Emission Vehicle...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-06-11

    ... twofold. The first is to reduce emissions of nitrogen oxide (NO X ) and volatile organic compound (VOC..., Incorporation by reference, Intergovernmental relations, Nitrogen dioxide, Ozone, Reporting and recordkeeping... begins]. 26.11.34.07 Initial NMOG Credit 12/17/07 6/11/13; [Insert page Account Balances. number where...

  6. 77 FR 44560 - Revisions to the Nevada State Implementation Plan, Washoe County Air Quality District

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-07-30

    ... emissions of criteria pollutants such as volatile organic compounds (VOC), oxides of nitrogen (NO X ), and... to, mass balance types of analysis, be made by the operator. Section 030.970A, Part 70 Permit... relations, Nitrogen dioxide, Ozone, Particulate matter, Reporting and recordkeeping requirements, Volatile...

  7. 78 FR 78315 - Revision to the Idaho State Implementation Plan; Approval of Fine Particulate Matter Control...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-12-26

    ... ), nitrogen oxides (NO X ), volatile organic compounds (VOC), and ammonia. An analysis of the baseline year... Idaho Transportation Department agreed to use straight salt and liquid salt brine throughout Franklin.... List of Subjects in 40 CFR Part 52 Environmental protection, Air pollution control, Nitrogen dioxide...

  8. Dry deposition of nitrogen and sulfur to ponderosa and jeffrey pine in the San Bernardino National Forest in southern California

    Treesearch

    Mark E. Fenn; Andrzej Bytnerowicz

    1993-01-01

    Little is known about the concentrations, deposition rates, and effects of nitrogenous and sulfurous compounds in photochemical smog in the San Bernardino National Forest (SBNF) in southern Calfirnia. Dry deposition of NO3- and NH4+ to foliage of ponderosa pine (Pinus...

  9. Nitrogen deposition in California forests: a review

    Treesearch

    Andrzej Bytnerowicz; Mark E. Fenn

    1996-01-01

    Atmospheric concentrations and deposition of the major nitrogenous (N) compounds and their biological effects in California forests are reviewed. Climatic characteristics of California are summarized in light of their effects on pollutant accumulation and transport. Over large areas of the state dry deposition is of greater magnitude than wet deposition due to the arid...

  10. Advances in the application of amino acid nitrogen isotopic analysis in ecological and biogeochemical studies

    USDA-ARS?s Scientific Manuscript database

    Compound-specific isotopic analysis of amino acids (CSIA-AA) has emerged in the last decade as a powerful approach for tracing the origins and fate of nitrogen in ecological and biogeochemical studies. This approach is based on the empirical knowledge that source AAs (i.e., phenylalanine), fractiona...

  11. Influence of shielding gas on the mechanical and metallurgical properties of DP-GMA-welded 5083-H321 aluminum alloy

    NASA Astrophysics Data System (ADS)

    Koushki, Amin Reza; Goodarzi, Massoud; Paidar, Moslem

    2016-12-01

    In the present research, 6-mm-thick 5083-H321 aluminum alloy was joined by the double-pulsed gas metal arc welding (DP-GMAW) process. The objective was to investigate the influence of the shielding gas composition on the microstructure and properties of GMA welds. A macrostructural study indicated that the addition of nitrogen and oxygen to the argon shielding gas resulted in better weld penetration. Furthermore, the tensile strength and bending strength of the welds were improved when oxygen and nitrogen (at concentrations as high as approximately 0.1vol%) were added to the shielding gas; however, these properties were adversely affected when the oxygen and nitrogen contents were increased further. This behavior was attributed to the formation of excessive brown and black oxide films on the bead surface, the formation of intermetallic compounds in the weld metal, and the formation of thicker oxide layers on the bead surface with increasing nitrogen and oxygen contents in the argon-based shielding gas. Analysis by energy-dispersive X-ray spectroscopy revealed that most of these compounds are nitrides or oxides.

  12. Bulk vs. amino acid stable N isotope estimations of metabolic status and contributions of nitrogen fixation to size-fractionated zooplankton biomass in the subtropical N Atlantic

    NASA Astrophysics Data System (ADS)

    Mompeán, Carmen; Bode, Antonio; Gier, Elizabeth; McCarthy, Matthew D.

    2016-08-01

    A comparative analysis of natural abundance of stable N isotopes (δ15N) in individual amino acids and bulk organic matter of size-fractionated plankton revealed the differential impact of nitrogen fixation through the food web in a transect across the subtropical North Atlantic. All δ15N measurements showed low values in the central region, followed by the western zone, while maximum δ15N values were found in the eastern zone. These results were consistent with the prevalence of nitrogen fixation in the central and western zones, and the influence of the west Africa upwelling in the eastern zone. Use of compound-specific amino acid isotope data (CSI-AA) revealed relatively low variability in the impact of diazotrophic nitrogen within the different plankton size fractions, while δ15N of bulk organic matter showed high variability with size. Explicit CSI-AA trophic position estimates showed a small increase with mean plankton size class and varied in a relatively narrow range 1.8-2.5), with the lowest values in the central zone. High correlations between bulk plankton δ15N and individual amino acids (in particular Phe and Thr), as well as reconstructed total protein δ15N values, suggest a set of new relationships that may be important to tracing direct plankton contributions to nitrogen recycling in the ocean, including detrital organic nitrogen pools. Overall, these new results represent the most detailed investigation of CSI-AA data in plankton size classes to date, and indicated a greater importance of diazotrophic N than suggested by concurrent measurements of bulk δ15N, abundance of large nitrogen fixing organisms or nitrogen fixation rates.

  13. A new 1D manganese(II) coordination polymer with end-to-end azide bridge and isonicotinoylhydrazone Schiff base ligand: Crystal structure, Hirshfeld surface, NBO and thermal analyses

    NASA Astrophysics Data System (ADS)

    Khani, S.; Montazerozohori, M.; Masoudiasl, A.; White, J. M.

    2018-02-01

    A new manganese (II) coordination polymer, [MnL2 (μ-1,3-N3)2]n, with co-ligands including azide anion and Schiff base based on isonicotinoylhydrazone has been synthesized and characterized. The crystal structure determination shows that the azide ligand acts as end-to-end (EE) bridging ligand and generates a one-dimensional coordination polymer. In this compound, each manganes (II) metal center is hexa-coordinated by four azide nitrogens and two pyridinic nitrogens for the formation of octahedral geometry. The analysis of crystal packing indicates that the 1D chain of [MnL2 (μ-1,3-N3)2]n, is stabilized as a 3D supramolecular network by intra- and inter-chain intermolecular interactions of X-H···Y (X = N and C, Y = O and N). Hirshfeld surface analysis and 2D fingerprint plots have been used for a more detailed investigation of intermolecular interactions. Also, natural bond orbital (NBO) analysis was performed to get information about atomic charge distributions, hybridizations and the strength of interactions. Finally, thermal analysis of compound showed its complete decomposition during three thermal steps.

  14. A combined evaluation of the characteristics and acute toxicity of antibiotic wastewater.

    PubMed

    Yu, Xin; Zuo, Jiane; Li, Ruixia; Gan, Lili; Li, Zaixing; Zhang, Fei

    2014-08-01

    The conventional parameters and acute toxicities of antibiotic wastewater collected from each treatment unit of an antibiotic wastewater treatment plant have been investigated. The investigation of the conventional parameters indicated that the antibiotic wastewater treatment plant performed well under the significant fluctuation in influent water quality. The results of acute toxicity indicated that the toxicity of antibiotic wastewater could be reduced by 94.3 percent on average after treatment. However, treated antibiotic effluents were still toxic to Vibrio fischeri. The toxicity of antibiotic production wastewater could be attributed to the joint effects of toxic compound mixtures in wastewater. Moreover, aerobic biological treatment processes, including sequencing batch reactor (SBR) and aerobic biofilm reactor, played the most important role in reducing toxicity by 92.4 percent. Pearson׳s correlation coefficients revealed that toxicity had a strong and positive linear correlation with organic substances, nitrogenous compounds, S(2-), volatile phenol, cyanide, As, Zn, Cd, Ni and Fe. Ammonia nitrogen (NH4(+)) was the greatest contributor to toxicity according to the stepwise regression method. The multiple regression model was a good fit for [TU50-15 min] as a function of [NH₄(+)] with the determination coefficient of 0.981. Copyright © 2014 Elsevier Inc. All rights reserved.

  15. [Flame retardants--use and hazards for human].

    PubMed

    Góralczyk, Katarzyna; Struciński, Paweł; Czaja, Katarzyna; Hernik, Agnieszka; Ludwicki, Jan K

    2002-01-01

    Flame retardants (FRs) are chemicals which added to materials during or after manufacture, inhibit or even suppress the combustion process due to their thermal stability. Large quantities of FRs are added to the plastic material (resins) in variety of electrical and electronic appliances including television and computer casing. The other uses of these compounds include production of building materials, upholstered furniture, textiles, wall covering, carpets, hydraulic fluids as well as vehicles and aircraft. Taking into account the chemical structure, there are five main groups of FRs: brominated, chlorinated, phosphorous-containing, nitrogen-containing (i.e. melamines) and inorganic compounds. Halogenated compounds, especially polybrominated diphenyl ethers (PBDEs), a class of brominated flame retardants, due to their lipophilic characteristics and persistence have become ubiquitous environmental contaminants. There are indications that PBDEs may affect hormone function acting as endocrine disruption and may be toxic for developing brain. These compounds have been associated with non-Hodgkin's lymphoma in humans, a variety of cancers in rodents and disruption of thyroid hormones balance. Similarly to other persistent halogenated compounds they are also able to affect the xenobiotic metabolizing enzymes activity. PBDEs are now found as residues in sediments, wildlife and human (milk, serum adipose tissue) samples. The predominant congeners in environmental samples, including human specimens are two congeners: 47 and 99. Currently, the estimated daily intake of PBDEs by adult humans is equal 51 ng x day-1 while by breast-fed infants equals 110 ng x day-1.

  16. High performance of a cobalt–nitrogen complex for the reduction and reductive coupling of nitro compounds into amines and their derivatives

    PubMed Central

    Zhou, Peng; Jiang, Liang; Wang, Fan; Deng, Kejian; Lv, Kangle; Zhang, Zehui

    2017-01-01

    Replacement of precious noble metal catalysts with low-cost, non-noble heterogeneous catalysts for chemoselective reduction and reductive coupling of nitro compounds holds tremendous promise for the clean synthesis of nitrogen-containing chemicals. We report a robust cobalt–nitrogen/carbon (Co–Nx/C-800-AT) catalyst for the reduction and reductive coupling of nitro compounds into amines and their derivates. The Co–Nx/C-800-AT catalyst was prepared by the pyrolysis of cobalt phthalocyanine–silica colloid composites and the subsequent removal of silica template and cobalt nanoparticles. The Co–Nx/C-800-AT catalyst showed extremely high activity, chemoselectivity, and stability toward the reduction of nitro compounds with H2, affording full conversion and >97% selectivity in water after 1.5 hours at 110°C and under a H2 pressure of 3.5 bar for all cases. The hydrogenation of nitrobenzene over the Co–Nx/C-800-AT catalyst can even be smoothly performed under very mild conditions (40°C and a H2 pressure of 1 bar) with an aniline yield of 98.7%. Moreover, the Co–Nx/C-800-AT catalyst has high activity toward the transfer hydrogenation of nitrobenzene into aniline and the reductive coupling of nitrobenzene into other derivates with high yields. These processes were carried out in an environmentally friendly manner without base and ligands. PMID:28232954

  17. Synthesis, biological evaluation, and computational studies of Tri- and tetracyclic nitrogen-bridgehead compounds as potent dual-acting AChE inhibitors and hH3 receptor antagonists.

    PubMed

    Darras, Fouad H; Pockes, Steffen; Huang, Guozheng; Wehle, Sarah; Strasser, Andrea; Wittmann, Hans-Joachim; Nimczick, Martin; Sotriffer, Christoph A; Decker, Michael

    2014-03-19

    Combination of AChE inhibiting and histamine H3 receptor antagonizing properties in a single molecule might show synergistic effects to improve cognitive deficits in Alzheimer's disease, since both pharmacological actions are able to enhance cholinergic neurotransmission in the cortex. However, whereas AChE inhibitors prevent hydrolysis of acetylcholine also peripherally, histamine H3 antagonists will raise acetylcholine levels mostly in the brain due to predominant occurrence of the receptor in the central nervous system. In this work, we designed and synthesized two novel classes of tri- and tetracyclic nitrogen-bridgehead compounds acting as dual AChE inhibitors and histamine H3 antagonists by combining the nitrogen-bridgehead moiety of novel AChE inhibitors with a second N-basic fragment based on the piperidinylpropoxy pharmacophore with different spacer lengths. Intensive structure-activity relationships (SARs) with regard to both biological targets led to compound 41 which showed balanced affinities as hAChE inhibitor with IC50 = 33.9 nM, and hH3R antagonism with Ki = 76.2 nM with greater than 200-fold selectivity over the other histamine receptor subtypes. Molecular docking studies were performed to explain the potent AChE inhibition of the target compounds and molecular dynamics studies to explain high affinity at the hH3R.

  18. Condensation Reactions and Formation of Amides, Esters, and Nitriles Under Hydrothermal Conditions

    NASA Astrophysics Data System (ADS)

    Rushdi, Ahmed I.; Simoneit, Bernd R. T.

    2004-06-01

    Hydrothermal pyrolysis experiments were performed to assess condensation (dehydration) reactions to amide, ester, and nitrile functionalities from lipid precursors. Beside product formation, organic compound alteration and stability were also evaluated. Mixtures of nonadecanoic acid, hexadecanedioic acid, or hexadecanamide with water, ammonium bicarbonate, and oxalic acid were heated at 300°C for 72 h. In addition, mixtures of ammonium bicarbonate and oxalic acid solutions were used to test the abiotic formation of organic nitrogen compounds at the same temperature. The resulting products were condensation compounds such as amides, nitriles, and minor quantities of N-methylalkyl amides, alkanols, and esters. Mixtures of alkyl amide in water or oxalic acid yielded mainly hydrolysis and dehydration products, and with ammonium bicarbonate and oxalic acid the yield of condensation products was enhanced. The synthesis experiments with oxalic acid and ammonium bicarbonate solutions yielded homologous series of alkyl amides, alkyl amines, alkanes, and alkanoic acids, all with no carbon number predominances. These organic nitrogen compounds are stable and survive under the elevated temperatures of hydrothermal fluids.

  19. Novel Rubidium Poly-Nitrogen Energetic Materials

    NASA Astrophysics Data System (ADS)

    Huff, Ashley; Steele, Brad; Oleynik, Ivan

    High-nitrogen content compounds are being actively explored with the goal of discovering new high-energy density materials with performance surpassing the conventional energetic materials such as HMX or RDX. Although pure polynitrogen compounds such as cg-N are predicted to deliver 10-fold increase in detonation pressure and detonation velocity of 30 km/s, their synthesis and recovery at ambient conditions is problematic. Doping polynitrogens with other elements is a viable route to promote metastability while reducing synthesis pressure. In this work, rubidium poly-nitrides are being investigated as candidates for high energy density materials. Using first principles evolutionary structure search methods performed at varying stoichiometries and several pressures ranging from 0 to 100 GPa, several new polynitrogen compounds have been discovered. The phase diagrams containing thermodynamically stable and lowest metastable phases are calculated and the dynamical stability of the promising materials is investigated at various pressures. Raman spectra and XRD patterns are also calculated to provide experimentally relevant information useful for identification of these compounds during their synthesis.

  20. The Search for Ammonia in Martian Soils with Curiosity's SAM Instrument

    NASA Technical Reports Server (NTRS)

    Wray, James J.; Archer, P. D.; Brinckerhoff, W. B.; Eigenbrode, J. L.; Franz, H. B.; Freissinet, C.; Glavin, D. P.; Mahaffy, P. R.; McKay, C. P.; Navarro-Gonzalez, R.; hide

    2013-01-01

    Nitrogen is the second or third most abundant constituent of the Martian atmosphere [1,2]. It is a bioessential element, a component of all amino acids and nucleic acids that make up proteins, DNA and RNA, so assessing its availability is a key part of Curiosity's mission to characterize Martian habitability. In oxidizing desert environments it is found in nitrate salts that co-occur with perchlorates [e.g., 3], inferred to be widespread in Mars soils [4-6]. A Mars nitrogen cycle has been proposed [7], yet prior missions have not constrained the state of surface N. Here we explore Curiosity's ability to detect N compounds using data from the rover's first solid sample. Companion abstracts describe evidence for nitrates [8] and for nitriles (C(triple bond)N) [9]; we focus here on nonnitrile, reduced-N compounds as inferred from bonded N-H. The simplest such compound is ammonia (NH3), found in many carbonaceous chondrite meteorites in NH4(+) salts and organic compounds [e.g., 10].

  1. Development of Chemical and Metabolite Sensors for Rhodococcus opacus PD630.

    PubMed

    DeLorenzo, Drew M; Henson, William R; Moon, Tae Seok

    2017-10-20

    Rhodococcus opacus PD630 is a nonmodel, Gram-positive bacterium that possesses desirable traits for biomass conversion, including consumption capabilities for lignocellulose-based sugars and toxic lignin-derived aromatic compounds, significant triacylglycerol accumulation, relatively rapid growth rate, and genetic tractability. However, few genetic elements have been directly characterized in R. opacus, limiting its application for lignocellulose bioconversion. Here, we report the characterization and development of genetic tools for tunable gene expression in R. opacus, including: (1) six fluorescent reporters for quantifying promoter output, (2) three chemically inducible promoters for variable gene expression, and (3) two classes of metabolite sensors derived from native R. opacus promoters that detect nitrogen levels or aromatic compounds. Using these tools, we also provide insights into native aromatic consumption pathways in R. opacus. Overall, this work expands the ability to control and characterize gene expression in R. opacus for future lignocellulose-based fuel and chemical production.

  2. A Structure-Activity Study with Aryl Acylamidases

    PubMed Central

    Villarreal, David T.; Turco, Ronald F.; Konopka, Allan

    1994-01-01

    We examined the relationship between chemical structure and biodegradability of acylanilide herbicides by using a set of model compounds. Four bacterial isolates (one gram-negative and three gram-positive) that grew on acetanilide were used. These soil isolates cleaved the amide bond of acetanilide via an aryl acylamidase reaction, producing aniline and the organic acid acetate. A series of acetanilide analogs with alkyl substitutions on the nitrogen atom or the aromatic ring were tested for their ability to induce aryl acylamidase activity and act as substrates for the enzyme. The substrate range, in general, was limited to those analogs not disubstituted in the ortho position of the benzene ring or which did not contain an alkyl group on the nitrogen atom. These same N-substituted compounds did not induce enzyme activity either, whereas the ortho-substituted compounds could in some cases. PMID:16349428

  3. Titan aerosol analogues: analysis of the nonvolatile tholins.

    PubMed

    Sarker, Niladri; Somogyi, Arpad; Lunine, Jonathan I; Smith, Mark A

    2003-01-01

    Laboratory experiments that produced tholins in a simulated Titan atmosphere were conducted. We report the first systematic analyses of these compounds using Fourier-transform ion cyclotron resonance mass spectrometry. The findings suggest surprising simplicity and nonrandomness in the mass distribution and regularity in species clusters. The degree of unsaturation generally increased with increasing molecular weight in a predictable fashion, and nitrogen is proposed as the dominant carrier of unsaturation. In detected compounds with a general formula of C(x)H(y)N(z), the carbon to nitrogen ratio (x/z) varied only slightly within a narrow limit, and decreased with increasing molecular weights. These compounds are of potential prebiotic interest since they sediment to the surface of Titan, and would dissolve readily in transient aqueous pools that might be generated from time to time by impacts and volcanic

  4. Direct asymmetric N-specific reaction of nitrosobenzene with aldehydes catalyzed by a chiral primary amine-based organocatalyst.

    PubMed

    Qin, Long; Li, Lei; Yi, Lei; Da, Chao-Shan; Zhou, Yi-Feng

    2011-08-01

    Nitroso compounds have two reactive nitrogen and oxygen atoms. It is interesting and important to perform a nitrogen or oxygen selective reaction with interesting substrates. These atom specific reactions are crucial to specifically synthesis of specific compounds. An enantioselective N-specific reaction of nitrosobenzene with unmodified aldehydes was successfully achieved catalyzed first by a variety of primary amine-based organocatalysts with higher yield and enantioselectivity. The bulkier substituted groups of the organocatalyst and two hydrogen bonds from the organocatalyst and the oxygen atom of nitrosobenzene make the reaction preferentially N-specific and predominantly afford R products. Copyright © 2011 Wiley-Liss, Inc.

  5. Effect of pH, application technique, and chlorine-to-nitrogen ratio on disinfectant activity of inorganic chloramines with pure culture bacteria.

    PubMed Central

    Ward, N R; Wolfe, R L; Olson, B H

    1984-01-01

    The influence of pH, application technique, and chlorine-to-nitrogen weight ratio on the bactericidal activity of inorganic chloramine compounds was determined with stock and environmental strains of Escherichia coli, Salmonella spp., Pseudomonas aeruginosa, Klebsiella pneumoniae, and Enterobacter cloacae. The rate of inactivation increased from 1.5 to 2 times as the chlorine-to-nitrogen weight ratio was adjusted from 2:1 to 5:1, 5 to 6 times as the pH was decreased from 8 to 6, and 5 to 6 times as the concentration was increased from 1 to 5 mg/liter. Separate additions of free chlorine and ammonia (concurrent addition and preammoniation) into seeded water at or below pH 7.5 resulted in killing comparable to that observed with free chlorine (99% inactivation in less than 20 s). At pH 8, inactivation by separate additions was considerably slower and was comparable to that by prereacted chloramine compounds (99% inactivation in 25 to 26 min). Determination of the effectiveness of inorganic chloramine compounds as primary disinfectants for drinking water must consider the method of application, pH and concentrations of chlorine and ammonia. PMID:6437328

  6. Tris-(hydroxyamino)triazines: high-affinity chelating tridentate O,N,O-hydroxylamine ligand for the cis-V(V)O2(+) cation.

    PubMed

    Nikolakis, Vladimiros A; Exarchou, Vassiliki; Jakusch, Tamás; Woolins, J Derek; Slawin, Alexandra M Z; Kiss, Tamás; Kabanos, Themistoklis A

    2010-10-14

    The treatment of the trichloro-1,3,5-triazine with N-methylhydroxylamine hydrochloride results in the replacement of the three chlorine atoms of the triazine ring with the function -N(OH)CH(3) yielding the symmetrical tris-(hydroxyamino)triazine ligand H(3)trihyat. Reaction of the ligand H(3)trihyat with NaV(V)O(3) in aqueous solution followed by addition of Ph(4)PCl gave the mononuclear vanadium(V) compound Ph(4)P[V(V)O(2)(Htrihyat)] (1). The structure of compound 1 was determined by X-ray crystallography and indicates that this compound has a distorted square-pyramidal arrangement around vanadium. The ligand Htrihyat(2-) is bonded to vanadium atom in a tridentate fashion at the triazine ring nitrogen atom and the two deprotonated hydroxylamido oxygen atoms. The high electron density of the triazine ring nitrogen atoms, which results from the resonative contribution of electrons of exocyclic nitrogen atoms, leads to a very strong V-N bond. The cis-[V(V)O(2)(Htrihyat)](-) species exhibits high hydrolytic stability in aqueous solution over a wide pH range, 2.5-11.5, as was evidenced by potentiometry.

  7. Hypoxanthine enhances the cured meat taste.

    PubMed

    Ichimura, Sayaka; Nakamura, Yukinobu; Yoshida, Yuka; Hattori, Akihito

    2017-02-01

    We evaluated the enhancement of cured meat taste during maturation by sensory analysis. We focused on the heat-stable sarcoplasmic fraction (HSSF) to identify the factors related to cured meat taste. Because the dry matter of HSSF contained more than 30% nitrogen, nitrogen compounds such as free amino acids, small peptides and adenosine triphosphate-related compounds seemed to be the important components of HSSF. The samples cured with HSSF for 2 h exhibited the same taste profile as ones cured without HSSF for 168 h. Therefore, the changes in the amount and fractions of nitrogen compounds were examined in HSSF during incubation from 0 to 168 h. The concentration of hypoxanthine (Hx) gradually increased, while inosine-5'-monophosphate decreased during the incubation. The samples cured with pickles containing various concentrations of Hx were subjected to sensory analysis. The addition of Hx, in a dose-dependent fashion, enhanced cured meat taste by maturation for 2 h. It was concluded that Hx is essential for the enhancement of cured meat taste. © 2016 The Authors. Animal Science Journal published by John Wiley & Sons Australia, Ltd on behalf of Japanese Society of Animal Science.

  8. Contamination control methods for gases used in the microlithography process

    NASA Astrophysics Data System (ADS)

    Rabellino, Larry; Applegarth, Chuck; Vergani, Giorgio

    2002-07-01

    Sensitivity to contamination continues to increase as the technology shrinks from 365 nm I-line lamp illumination to 13.4 nm Extreme Ultraviolet laser activated plasma. Gas borne impurities can be readily distributed within the system, remaining both suspended in the gas and attached to critical surfaces. Effects from a variety of contamination, some well characterized and others not, remain a continuing obstacle for stepper manufacturers and users. Impurities like oxygen, moisture and hydrocarbons in parts per billion levels can absorb light, reducing the light intensity and subsequently reducing the consistence of the process. Moisture, sulfur compounds, ammonia, acid compounds and organic compounds such as hydrocarbons can deposit on lens or mirror surfaces affecting image quality. Regular lens replacement or removal for cleaning is a costly option and in-situ cleaning processes must be carefully managed to avoid recontamination of the system. The contamination can come from outside the controlled environment (local gas supply, piping system, & leaks), or from the materials moving into the controlled environment; or contamination may be generated inside the controlled environment as a result of the process itself. The release of amines can occur as a result of the degassing of the photo-resists. For the manufacturer and user of stepper equipment, the challenge is not in predictable contamination, but the variable or unpredictable contamination in the process. One type of unpredictable contamination may be variation in the environmental conditions when producing the nitrogen gas and Clean Dry Air (CDA). Variation in the CDA, nitrogen and xenon may range from parts per billion to parts per million. The risk due to uncontrolled or unmonitored variation in gas quality can be directly related to product defects. Global location can significantly affect the gas quality, due to the ambient air quality (for nitrogen and CDA), production methods, gas handling equipment maintenance, transportation and storage processes. Fortunately, technology has been developed which can remove the killer impurities from these processes. This paper will review processes, and purification media that can be used in the photolithography processes, and detail the advances in purification technologies for removal of hydrocarbons, oxygen (where applicable), moisture, carbon dioxide, carbon monoxide, hydrogen, nitrogen (where applicable), sulfur compounds, ammonia and acid compounds from process gases such as nitrogen, CDA, argon, krypton and xenon.

  9. Simultaneous determination of total nitrogen and total phosphorus in environmental waters using alkaline persulfate digestion and ion chromatography.

    PubMed

    De Borba, Brian M; Jack, Richard F; Rohrer, Jeffrey S; Wirt, Joan; Wang, Dongmei

    2014-11-21

    An ion chromatography (IC) method was developed for the simultaneous determination of total nitrogen and total phosphorus after alkaline persulfate digestion. This study takes advantage of advances in construction of high-resolution, high-capacity anion-exchange columns that can better tolerate the matrices typically encountered when a determination of total nitrogen and total phosphorous is required. Here, we used an electrolytically generated hydroxide eluent combined with a high-capacity, hydroxide-selective, anion-exchange column for the determination of total nitrogen (as nitrate-N) and total phosphorus (as phosphate-P) in environmental samples by IC. This method yielded LODs for nitrate-N and phosphate-P of 1.0 and 1.3 μg/L, respectively. The LOQs determined for these analytes were 3.4 and 4.2 μg/L, respectively. Due to the dilution factor required and the blank nitrate-N concentration after the persulfate digestion, the quantification limits increased for nitrate-N and phosphate-P to 171 and 63 μg/L, respectively. The suitability of the method was evaluated by determining the nitrogen and phosphorus concentrations from known concentrations of organic-containing nitrogen and phosphorus compounds. In addition, environmental samples consisting of six different wastewaters and 48 reservoir samples were evaluated for total nitrogen and phosphorus. The recoveries of nitrogen and phosphorus from the organic-containing compounds ranged from 93.1 to 100.1% and 85.2 to 97.1%, respectively. In addition, good correlation between results obtained by the colorimetric method and IC was also observed. The linearity, accuracy, and evaluation of potential interferences for determining TN and TP will be discussed. Copyright © 2014 Elsevier B.V. All rights reserved.

  10. Autohydrolysis of agricultural residues: study of reaction byproducts.

    PubMed

    Garrote, Gil; Falqué, Elena; Domínguez, Herminia; Parajó, Juan Carlos

    2007-07-01

    Samples of rice husks and corn cobs were subjected to hydrothermal treatments in aqueous media under conditions leading to maximal xylooligomer concentration, and the reaction liquors were extracted with dichloromethane (DCM) to assess the type and amount of reaction byproducts with potential application as food ingredients and cosmetics. The identified DCM-soluble compounds were classified in four categories (sugar-derived compounds, lignin-derived compounds, nitrogen-containing compounds and fatty acids). The experimental results were compared with literature data.

  11. Synthesis of 4-hydroxy-1-methylindole and benzo[b]thiophen-4-ol based unnatural flavonoids as new class of antimicrobial agents.

    PubMed

    Yadav, Prem P; Gupta, Prasoon; Chaturvedi, A K; Shukla, P K; Maurya, Rakesh

    2005-03-01

    Synthesis of nitrogen and sulfur heterocyclic mimics of furanoflavonoids have been achieved for the first time. Synthesized flavonoid alkaloids and thiophenyl flavonoids have been screened for antifungal and antibacterial activities. All the test compounds barring 25 exhibited antifungal activity. The compound 19 was the best and showed comparable MICs to the known compound karanjin. Compounds 5, 12, 14 and 22 also showed comparable MIC to karanjin.

  12. Summary of Surface-Water Quality Data from the Illinois River Basin in Northeast Oklahoma, 1970-2007

    USGS Publications Warehouse

    Andrews, William J.; Becker, Mark F.; Smith, S. Jerrod; Tortorelli, Robert L.

    2009-01-01

    The quality of streams in the Illinois River Basin of northeastern Oklahoma is potentially threatened by increased quantities of wastes discharged from increasing human populations, grazing of about 160,000 cattle, and confined animal feeding operations raising about 20 million chickens. Increasing numbers of humans and livestock in the basin contribute nutrients and bacteria to surface water and groundwater, causing greater than the typical concentrations of those constituents for this region. Consequences of increasing contributions of these substances can include increased algal growth (eutrophication) in streams and lakes; impairment of habitat for native aquatic animals, including desirable game fish species; impairment of drinking-water quality by sediments, turbidity, taste-and-odor causing chemicals, toxic algal compounds, and bacteria; and reduction in the aesthetic quality of the streams. The U.S. Geological Survey, in cooperation with the Oklahoma Scenic Rivers Commission, prepared this report to summarize the surface-water-quality data collected by the U.S. Geological Survey at five long-term surface-water-quality monitoring sites. The data summarized include major ions, nutrients, sediment, and fecal-indicator bacteria from the Illinois River Basin in Oklahoma for 1970 through 2007. General water chemistry, concentrations of nitrogen and phosphorus compounds, chlorophyll-a (an indicator of algal biomass), fecal-indicator bacteria counts, and sediment concentrations were similar among the five long-term monitoring sites in the Illinois River Basin in northeast Oklahoma. Most water samples were phosphorus-limited, meaning that they contained a smaller proportion of phosphorus, relative to nitrogen, than typically occurs in algal tissues. Greater degrees of nitrogen limitation occurred at three of the five sites which were sampled back to the 1970s, probably due to use of detergents containing greater concentrations of phosphorus than in subsequent periods. Concentrations of nitrogen, phosphorus, and sediment, and counts of bacteria generally increased with streamflow at the five sites, probably due to runoff from the land surface and re-suspension of streambed sediments. Phosphorus concentrations typically exceeded the Oklahoma standard of 0.037 milligrams per liter for Scenic Rivers. Concentrations of chlorophyll-a in phytoplankton in water samples collected at the five sites were not well correlated with streamflow, nor to concentrations of the nutrients nitrogen and phosphorus, probably because much of the algae growing in these streams are periphyton attached to streambed cobbles and other debris, rather than phytoplankton in the water column. Sediment concentrations correlated with phosphorus concentrations in water samples collected at the sites, probably due to sorption of phosphorus to soil particles and streambed sediments and runoff of soils and animal wastes at the land surface and resuspension of streambed sediments and phosphorus during wet, high-flow periods. Fecal coliform bacteria counts at the five sites sometimes exceeded the Oklahoma Primary Body Contact Standard of 400 colonies per 100 milliliters when streamflows were greater than 1000 cubic feet per second. Ultimately, Lake Tenkiller, an important ecological and economic resource for the region, receives the compounds that runoff the land surface or seep to local streams from groundwater in the basin. Because of eutrophication from increased nutrient loading, Lake Tenkiller is listed for impairment by diminished dissolved oxygen concentrations, phosphorus, and chlorophyll-a by the State of Oklahoma in evaluation of surface-water quality required by section 303d of the Clean Water Act. Stored phosphorus in soils and streambed and lakebed sediments may continue to provide phosphorus to local streams and lakes for decades to come. Steps are being made to reduce local sources of phosphorus, including upgrades in capacity and effective

  13. Effects of different microbes on fermenting feed for sea cucumber ( Apostichopus japonicus)

    NASA Astrophysics Data System (ADS)

    Jiang, Yan; Wang, Yingeng; Mai, Kangsen; Zhang, Zheng; Liao, Meijie; Rong, Xiaojun

    2015-10-01

    The effects of different microbes on fermenting feed for sea cucumber ( Apostichopus japonicus) were compared to select the optimal fermentation strain in this study. Saccharomgces cerevisae, Candida utilis, Bacillus subtilis and Geotrichum candidum were independently added into the experimental compound feed, while only saline was mixed with the control feed. The fermentation treatments were inoculated with 10% seed solution under the condition of 25°C and 70% water content, which lasted for 5 days to elucidate the optimal microbe strain for fermenting effect. Physicochemical indexes and sensorial characteristics were measured per day during the fermentation. The indexes included dry matter recovery (DMR), crude protein (CP), the percentage of amino acid nitrogen to total nitrogen (AA-N/tN), the percentage of ammonia nitrogen to total nitrogen (NH3-N/tN), and the ratio of fermentation strains and vibrios to the total microbes, color, smell and viscosity. The results showed that DMR, CP and AA-N/tN of the S. cerevisae group reached the highest level on day 3, but the ratio of fermentation strain was second to C. utilis group. In addition, its NH3-N/tN and the ratio of vibrios were maintained at low levels, and the sensory evaluation score including smell, color and viscosity was the highest in S. cerevisae group on day 3. Therefore, S. cerevisae could be the optimal strain for the feed fermentation for sea cucumber. This research developed a new production method of fermentation feed for sea cucumber.

  14. Nonflammable potting, encapsulating and/or conformal coating compound

    NASA Technical Reports Server (NTRS)

    Kline, H. F.; Dawn, F.

    1972-01-01

    Compound formed from dimethylpolysiloxane, ammonium phosphate, and ground glass is nonflammable in air environment and self-extingushing in atmosphere of 60 percent oxygen and 40 percent nitrogen. Material may have applications for reducing industrial fire hazards and should interest aircraft industry, machinery manufacturers, and automotive industry.

  15. Sources and sinks of nitrogen and phosphorus to a deep, oligotrophic lake, Lake Crescent, Olympic National Park, Washington

    USGS Publications Warehouse

    Moran, P.W.; Cox, S.E.; Embrey, S.S.; Huffman, R.L.; Olsen, T.D.; Fradkin, S.C.

    2012-01-01

    Lake Crescent, in Olympic National Park in the northwest corner of Washington State is a deep-water lake renowned for its pristine water quality and oligotrophic nature. To examine the major sources and sinks of nutrients (as total nitrogen, total phosphorus, and dissolved nitrate), a study was conducted in the Lake Crescent watershed. The study involved measuring five major inflow streams, the Lyre River as the major outflow, recording weather and climatic data, coring lake bed sediment, and analyzing nutrient chemistry in several relevant media over 14 months. Water samples for total nitrogen, total phosphorous, and dissolved nitrate from the five inflow streams, the outlet Lyre River, and two stations in the lake were collected monthly from May 2006 through May 2007. Periodic samples of shallow water from temporary sampling wells were collected at numerous locations around the lake. Concentrations of nutrients detected in Lake Crescent and tributaries were then applied to the water budget estimates to arrive at monthly and annual loads from various environmental components within the watershed. Other sources, such as leaf litter, pollen, or automobile exhaust were estimated from annual values obtained from various literature sources. This information then was used to construct a nutrient budget for total nitrogen and total phosphorus. The nitrogen budget generally highlights vehicle traffic-diesel trucks in particular-along U.S. Highway 101 as a potential major anthropogenic source of nitrogen compounds in the lake. In contrast, contribution of nitrogen compounds from onsite septic systems appears to be relatively minor related to the other sources identified.

  16. Nitroaromatic Compounds, from Synthesis to Biodegradation

    PubMed Central

    Ju, Kou-San; Parales, Rebecca E.

    2010-01-01

    Summary: Nitroaromatic compounds are relatively rare in nature and have been introduced into the environment mainly by human activities. This important class of industrial chemicals is widely used in the synthesis of many diverse products, including dyes, polymers, pesticides, and explosives. Unfortunately, their extensive use has led to environmental contamination of soil and groundwater. The nitro group, which provides chemical and functional diversity in these molecules, also contributes to the recalcitrance of these compounds to biodegradation. The electron-withdrawing nature of the nitro group, in concert with the stability of the benzene ring, makes nitroaromatic compounds resistant to oxidative degradation. Recalcitrance is further compounded by their acute toxicity, mutagenicity, and easy reduction into carcinogenic aromatic amines. Nitroaromatic compounds are hazardous to human health and are registered on the U.S. Environmental Protection Agency's list of priority pollutants for environmental remediation. Although the majority of these compounds are synthetic in nature, microorganisms in contaminated environments have rapidly adapted to their presence by evolving new biodegradation pathways that take advantage of them as sources of carbon, nitrogen, and energy. This review provides an overview of the synthesis of both man-made and biogenic nitroaromatic compounds, the bacteria that have been identified to grow on and completely mineralize nitroaromatic compounds, and the pathways that are present in these strains. The possible evolutionary origins of the newly evolved pathways are also discussed. PMID:20508249

  17. Chronic bioassays of rainbow trout fry with compounds representative of contaminants in Great Lakes fish

    USGS Publications Warehouse

    Passino-Reader, Dora R.; Berlin, William H.; Hickey, James P.

    1995-01-01

    To evaluate the hazard of organic compounds detected in Great Lakes fish by gas chromatography/mass spectrometry, we tested compounds representative of heterocyclic nitrogen compounds, polycyclic aromatic hydrocarbons, and cyclic alkanes and alkenes. Sixty-day bioassays on the effects of nicotine, phenanthrene, pinane, and pinene on the behavior, growth, and survival of rainbow trout fry, Oncorhynchus mykiss, were conducted in a large, constant-flow, temperature-controlled water system. The following 60-day LCSO's were determined (mg/L): nicotine 5.0, phenanthrene 0.2, pinane 0.8, and pinene 1.2. Values of lowest observed effects level (LOEL) and no observed effects level (NOEL) showed that growth was generally as sensitive an endpoint as behavior and was more sensitive than time of swim-up. The 60-day LC50 values for rainbow trout were compared with earlier acute bioassays with Daphnia pulexand rainbow trout and chronic bioassays with D.pulex conducted at the Great Lakes Science Center. Rainbow trout fry were less sensitive than daphnids in all tests, indicating that toxicity tests with daphnids should be protective of salmonid fry for these types of compounds. The results for representative compounds indicate that these classes of compounds should be included in aquatic risk assessments at sites in the Great Lakes.

  18. [Ammonia volatilization of slow release compound fertilizer in different soils water conditions].

    PubMed

    Hu, Xiao-feng; Wang, Zheng-yin; You, Yuan; Li, Jing-chao

    2010-08-01

    By using venting method incubation experiment, we studied the ammonia volatilization and kinetics characteristics of uncoated slowed release compound fertilizer (SRF) under different soil water conditions and the growth and nitrogen utilization efficiency of rice in pot experiment. Results indicated that the ammonia volatilization of SRF under waterflooding reached the peak ahead of 3-4 days compared to the moist treatment. The peak and accumulation of ammonia volatilization in the waterflooding treatments were higher than those under the moist condition. SRF could significantly reduce total ammonia volatilization compared to the common compound fertilizer (CCF), reduced by 50.6% and 22.8% in the moist treatment and reduced by 24.2% and 10.4% in the waterflooding treatment,but the loss of ammonia volatilization of SRF was higher significantly than that of the coated fertilizer (CRF). Ammonia volatilization increased with the increasing of fertilizer application. The dynamics of ammonia volatilization of SRF could be quantitatively described with three equations: the first order kinetics equation, Elovich equation and parabola equation. Compared to moist condition, the biomass of rice plant in SRF, CCF and SRF treatments increased by 67.86%, 78.25% and 48.75%, and nitrogen utilization efficiency increased by 57.73%, 80.70% and 12.06% under waterflooding condition, respectively. Comparing with CCF, nitrogen utilization efficiency in SRF treatment improved by 59.10% and 10.40% under two soil moisture conditions. SRF could reduce ammonia volatilization and improve biomass and nitrogen utilization efficiency.

  19. Bio-markers and the search for extinct life on Mars

    NASA Technical Reports Server (NTRS)

    Schwartz, D. E.; Mancinelli, R. L.

    1989-01-01

    In order to predict what biomarkers could be used on Mars, several biomarkers, or key signatures, of extinct life on earth are identified. Some of these biomarkers which may be applicable to Mars include reduced carbon and nitrogen compounds, CO3(2-), SO4(2-), NO3(-), Mg, Mn, Fe, and the isotopic ratios of C, N, and S. It is suggested that a fully equipped Mars rover might be able to perform analyses to measure most of these biomarkers while on the Martian surface.

  20. Global consequences of afforestation and bioenergy cultivation on ecosystem service indicators

    NASA Astrophysics Data System (ADS)

    Krause, Andreas; Pugh, Thomas A. M.; Bayer, Anita D.; Doelman, Jonathan C.; Humpenöder, Florian; Anthoni, Peter; Olin, Stefan; Bodirsky, Benjamin L.; Popp, Alexander; Stehfest, Elke; Arneth, Almut

    2017-11-01

    Land management for carbon storage is discussed as being indispensable for climate change mitigation because of its large potential to remove carbon dioxide from the atmosphere, and to avoid further emissions from deforestation. However, the acceptance and feasibility of land-based mitigation projects depends on potential side effects on other important ecosystem functions and their services. Here, we use projections of future land use and land cover for different land-based mitigation options from two land-use models (IMAGE and MAgPIE) and evaluate their effects with a global dynamic vegetation model (LPJ-GUESS). In the land-use models, carbon removal was achieved either via growth of bioenergy crops combined with carbon capture and storage, via avoided deforestation and afforestation, or via a combination of both. We compare these scenarios to a reference scenario without land-based mitigation and analyse the LPJ-GUESS simulations with the aim of assessing synergies and trade-offs across a range of ecosystem service indicators: carbon storage, surface albedo, evapotranspiration, water runoff, crop production, nitrogen loss, and emissions of biogenic volatile organic compounds. In our mitigation simulations cumulative carbon storage by year 2099 ranged between 55 and 89 GtC. Other ecosystem service indicators were influenced heterogeneously both positively and negatively, with large variability across regions and land-use scenarios. Avoided deforestation and afforestation led to an increase in evapotranspiration and enhanced emissions of biogenic volatile organic compounds, and to a decrease in albedo, runoff, and nitrogen loss. Crop production could also decrease in the afforestation scenarios as a result of reduced crop area, especially for MAgPIE land-use patterns, if assumed increases in crop yields cannot be realized. Bioenergy-based climate change mitigation was projected to affect less area globally than in the forest expansion scenarios, and resulted in less pronounced changes in most ecosystem service indicators than forest-based mitigation, but included a possible decrease in nitrogen loss, crop production, and biogenic volatile organic compounds emissions.

  1. Where the rubber meets the road: What is needed to sustainably manage reactive nitrogen in the United States?

    EPA Science Inventory

    Reactive nitrogen (N) is essential for food, fuel and fiber production of a growing human population. Intensification of reactive N (defined as any N compound other than N2) release to the environment, however, has resulted in important and mounting impacts on human health and e...

  2. The Load of Lightning-induced Nitrogen Oxides and Its Impact on the Ground-level Ozone during Summertime over the Mountain West States

    EPA Science Inventory

    Lightning-induced nitrogen oxides (LNOX), in the presence of sunlight, volatile organic compounds and water, can be a relatively large but uncertain source for ozone (O3) and hydroxyl radical (OH) in the atmosphere. Using lightning flash data from the National Lightning Detection...

  3. OBSERVATION-BASED ASSESSMENT OF THE IMPACT OF NITROGEN OXIDES EMISSIONS REDUCTIONS ON OZONE AIR QUALITY OVER THE EASTERN UNITED STATES

    EPA Science Inventory

    Ozone is produced by chemical interactions involving nitrogen oxides (NOx) and Volatile Organic Compounds (VOCs) in the presence of sunlight. At high concentrations, ground-level ozone has been shown to be harmful to human health and the environment. It has been reco...

  4. 78 FR 35181 - Approval and Promulgation of Air Quality Implementation Plans; Utah; Revisions to Utah...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-06-12

    ... replaced with low oxide of nitrogen burners. We are proposing to approve R307-401-4(1) and (3) because they... , 4 tons per year for volatile organic compounds (VOCs), nitrogen dioxide (NO 2 ), and sulfur dioxide... levels represent a reasonable balance between environmental protection and economic growth (76 FR 38758...

  5. Hydrogen cyanide polymers, comets and the origin of life.

    PubMed

    Matthews, Clifford N; Minard, Robert D

    2006-01-01

    Hydrogen cyanide polymers--heterogeneous solids ranging in colour from yellow to orange to brown to black--could be major components of the dark matter observed on many bodies of the outer solar system including asteroids, moons, planets and, especially, comets. The presence on cometary nuclei of frozen volatiles such as methane, ammonia and water subjected to high energy sources makes them attractive sites for the ready formation and condensed-phase polymerization of hydrogen cyanide. This could account for the dark crust observed on Comet Halley in 1986 by the Vega and Giotto missions. Dust emanating from its nucleus would arise partly from HCN polymers as suggested by the Giotto detection of free hydrogen cyanide, CN radicals, solid particles consisting only of H, C and N, or only of H, C, N, O, and nitrogen-containing organic compounds. Further evidence for cometary HCN polymers could be expected from in situ analysis of the ejected material from Comet Tempel 1 after collision with the impactor probe from the two-stage Deep Impact mission on July 4, 2005. Even more revealing will be actual samples of dust collected from the coma of Comet Wild 2 by the Stardust mission, due to return to Earth in January 2006 for analyses which we have predicted will detect these polymers and related compounds. In situ results have already shown that nitriles and polymers of hydrogen cyanide are probable components of the cometary dust that struck the Cometary and Interstellar Dust Analyzer of the Stardust spacecraft as it approached Comet Wild 2 on January 2, 2004. Preliminary evidence (January 2005) obtained by the Huygens probe of the ongoing Cassini-Huygens mission to Saturn and its satellites indicates the presence of nitrogen-containing organic compounds in the refractory organic cores of the aerosols that give rise to the orange haze high in the atmosphere of Titan, Saturn's largest moon. Our continuing investigations suggest that HCN polymers are basically of two types: ladder structures with conjugated -C=N- bonds and polyamidines readily converted by water to polypeptides. Thermochemolysis GC-MS studies show that cleavage products of the polymer include alpha-amino acids, nitrogen heterocycles such as purines and pyrimidines, and provide evidence for peptide linkages. Hydrogen cyanide polymers are a plausible link between cosmochemistry and the origin of informational macromolecules. Implications for prebiotic chemistry are profound. Following persistent bolide bombardment, primitive Earth may have been covered by water and carbonaceous compounds, particularly HCN polymers which would have supplied essential components for establishing protein/nucleic acid life.

  6. Supramolecular packing and polymorph screening of N-isonicotinoyl arylketone hydrazones with phenol and amino modifications

    NASA Astrophysics Data System (ADS)

    Hean, Duane; Michael, Joseph P.; Lemmerer, Andreas

    2018-04-01

    Thirteen structural variants based on the (E)-N‧-(1-arylethylidene)pyridohydrazide template were prepared, investigated and screened for possible polymorphic behaviour. Four variants showed from Differential Scanning Calorimetry Scans thermal events indicative of new solid-state phases. The thirteen variants included substituents R = sbnd OH or sbnd NH2 placed at ortho, meta and para positions on the phenyl ring; and shifting the pyridyl nitrogen between positions 4-, 3- and 2-. The crystal structures of twelve of the compounds were determined to explore their supramolecular structures. The outcomes of these modifications demonstrated that the pyridyl nitrogen at the 2- position is 'locked' by forming a hydrogen bond with the amide hydrogen; while placing the pyridyl nitrogen at positions 3- and 4- offers a greater opportunity for hydrogen bonding with neighbouring molecules. Such interactions include Osbnd H⋯N, Nsbnd H⋯N, Osbnd H⋯O, Nsbnd H⋯O, Nsbnd H⋯π, π⋯π stacking, as well as other weaker interactions such as Csbnd H⋯N, Csbnd H⋯O, Csbnd H⋯N(pyridyl). When OH or NH2 donors are placed in the ortho position, an intramolecular hydrogen bond is formed between the acceptor hydrazone nitrogen and the respective donor. The meta- and para-positioned donors form an unpredictable array of supramolecular structures by forming hydrogen-bonded chains with the pyridyl nitrogen and carbonyl acceptors respectively. In addition to the intramolecular and chain hydrogen bond formation demonstrated throughout the crystal structures under investigation, larger order hydrogen-bonded rings were also observed in some of the supramolecular aggregations. The extent of the hydrogen-bonded ring formations range from two to six molecular participants depending on the specific crystal structure.

  7. A Continuous Flow System for the Measurement of Ambient Nitrogen Oxides [NO + NO2] Using Rhodamine B Hydrazide as a Chemosensor.

    PubMed

    Malingappa, Pandurangappa; Yarradoddappa, Venkataramanappa

    2014-01-01

    A new chemosensor has been used to monitor atmospheric nitrogen oxides [NO + NO2] at parts per billion (ppb) level. It is based on the catalytic reaction of nitrogen oxides with rhodamine B hydrazide (RBH) to produce a colored compound through the hydrolysis of the amide bond of the molecule. A simple colorimeter has been used to monitor atmospheric nitrogen dioxide at ppb level. The air samples were purged through a sampling cuvette containing RBH solution using peristaltic pump. The proposed method has been successfully applied to monitor the ambient nitrogen dioxide levels at traffic junction points within the city limits and the results obtained are compared with the standard Griess-Ilosvay method.

  8. Mass spectral analysis of N-oxides of Chemical Weapons Convention related aminoethanols under electrospray ionization conditions.

    PubMed

    Sridhar, L; Karthikraj, R; Murty, M R V S; Raju, N Prasada; Vairamani, M; Prabhakar, S

    2011-02-28

    N,N'-Dialkylaminoethanols are the hydrolyzed products or precursors of chemical warfare agents such as V-agents and nitrogen mustards, and they are prone to undergo oxidation in environmental matrices or during decontamination processes. Consequently, screening of the oxidized products of aminoethanols in aqueous samples is an important task in the verification of chemical weapons convention-related chemicals. Here we report the successful characterization of the N-oxides of N,N'-dialkylaminoethanols, alkyl diethanolamines, and triethanolamine using positive ion electrospray ionization mass spectrometry. The collision-induced dissociation (CID) spectra of the [M+H](+) and [M+Na](+) ions show diagnostic product ions that enable the unambiguous identification of the studied N-oxides, including those of isomeric compounds. The proposed fragmentation pathways are supported by high-resolution mass spectrometry data and product/precursor ion spectra. The CID spectra of [M+H](+) ions included [MH-CH(4)O(2)](+) as the key product ion, in addition to a distinctive alkene loss that allowed us to recognize the alkyl group attached to the nitrogen. The [M+Na](+) ions show characteristic product ions due to the loss of groups (R) attached to nitrogen either as a radical (R) or as a molecule [R+H or (R-H)] after hydrogen migration. Copyright © 2011 John Wiley & Sons, Ltd.

  9. Space-Based Diagnosis of Surface Ozone Sensitivity to Anthropogenic Emissions

    NASA Technical Reports Server (NTRS)

    Martin, Randall V.; Fiore, Arlene M.; VanDonkelaar, Aaron

    2004-01-01

    We present a novel capability in satellite remote sensing with implications for air pollution control strategy. We show that the ratio of formaldehyde columns to tropospheric nitrogen dioxide columns is an indicator of the relative sensitivity of surface ozone to emissions of nitrogen oxides (NO(x) = NO + NO2) and volatile organic compounds (VOCs). The diagnosis from these space-based observations is highly consistent with current understanding of surface ozone chemistry based on in situ observations. The satellite-derived ratios indicate that surface ozone is more sensitive to emissions of NO(x) than of VOCs throughout most continental regions of the Northern Hemisphere during summer. Exceptions include Los Angeles and industrial areas of Germany. A seasonal transition occurs in the fall when surface ozone becomes less sensitive to NOx and more sensitive to VOCs.

  10. The development of a volatile organics concentrator for use in monitoring Space Station water quality

    NASA Technical Reports Server (NTRS)

    Bodek, Itamar; Ehntholt, Daniel J.; Stolki, Thomas J.; Valentine, James R.; Trabanino, Rudy; Webb, Johanna V.; Sauer, Richard L.

    1991-01-01

    A breadboard concept of a volatile organics concentrator (VOC) is manufactured and tested for optimized water-quality analysis in a space environment. The VOC system is attached to a gas chromatograph/mass spectrometer to analyze the volatile chemicals relevant to the operation of Space Station Freedom. The preliminary tests include: (1) comparisons with analyses based on direct on-column injections of standards; (2) analyses of iodinated volatile organics; (3) comparisons of nitrogen vs helium as the chromatography carrier gas; and (4) measurements of collection efficiency. The VOC can analyze EPA method-624 analytes at comparable detection using flame-ionization detection and can analyze volatile iodinated compounds. The breadboard has good reproducibility and can use nitrogen as a carrier gas; good results are noted for the collection and concentration levels and for water removal.

  11. Biological cycling of atmospheric trace gases

    NASA Technical Reports Server (NTRS)

    Hitchcock, D. R.; Wechsler, A. E.

    1972-01-01

    A detailed critical review was conducted of present knowledge of the influence of biological processes on the cycling of selected atmospheric gas constituents--methane, carbon monoxide, and gaseous compounds of nitrogen (nitrous oxide, ammonia, nitric oxide, and nitrogen dioxide) and sulfur (hydrogen sulfide and sulfur dioxide). The identification was included of biological and other sources of each gas, a survey of abundance measurements reported in the literature, and a review of the atmospheric fate of each contituent. Information is provided on which to base conclusions regarding the importance of biological processes on the atmospheric distribution and surface-atmosphere exchange of each constituent, and a basis for estimating the adequacy of present knowledge of these factors. A preliminary analysis was conducted of the feasibility of monitoring the biologically influenced temporal and spatial variations in abundance of these gases in the atmosphere from satellites.

  12. 78 FR 38587 - Approval and Promulgation of Air Quality Implementation Plans; Connecticut; Reasonably Available...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-06-27

    ... reasonably available control technology (RACT) for oxides of nitrogen (NO X ) and volatile organic compounds.... I. Background and Purpose II. Connecticut's Reasonably Available Control Technology Certification... controlling volatile organic compound emissions that Connecticut submitted to EPA on July 20, 2007. \\1\\ The...

  13. Oxidation of refractory sulfur compounds over Ti-containing mesoporous molecular sieves prepared by using a fluorosilicon compound.

    PubMed

    Jeong, Kwang-Eun; Cho, Chin-Soo; Chae, Ho-Jeong; Kim, Chul-Ung; Jeong, Soon-Yong

    2010-05-01

    Titanium containing mesoporous molecular sieve (Ti-MMS) catalysts were studied for the oxidative desulfurization of refractory sulfur compounds. Ti-MMS catalysts were synthesized from fluorosilicon compounds and Ti with the hydrolysis reaction of H2SiF6 in an ammonia-surfactant mixed solution. The solid products were characterized by XRD, XRF, nitrogen adsorption, and diffuse reflectance UV-vis spectroscopy. Effects of Ti loading and oxidant/sulfur mole ratio, and sulfur species on ODS activity were investigated.

  14. Temporal variation in leaf nitrogen partitioning of a broad-leaved evergreen tree, Quercus myrsinaefolia.

    PubMed

    Yasumura, Yuko; Ishida, Atsushi

    2011-01-01

    We examined temporal changes in the amount of nitrogenous compounds in leaves from the outer and inner parts of the crown of Quercus myrsinaefolia growing in a seasonal climate. Throughout the leaf life span, metabolic protein and Rubisco content closely correlated with total nitrogen content, while structural protein content was relatively stable after full leaf expansion. Chlorophyll content was affected by shading as well as total nitrogen content in outer leaves that were overtopped by new shoots in the second year. Outer leaves showed a large seasonal variation in photosynthetic nitrogen-use efficiency (PNUE; the light-saturated photosynthetic rate per unit leaf nitrogen content) during the first year of their life, with PNUE decreasing from the peak in summer towards winter. Outer and inner leaves both showed age-related decline in PNUE in the second year. There were no such drastic changes in leaf nitrogen partitioning that could explain seasonal and yearly variations in PNUE. Nitrogen resorption occurred in overwintering leaves in spring. Metabolic protein explained the majority of nitrogen being resorbed, whereas structural protein, which was low in degradability, contributed little to nitrogen resorption.

  15. 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.

  16. Plasma impregnation of wood with fire retardants

    NASA Astrophysics Data System (ADS)

    Pabeliña, Karel G.; Lumban, Carmencita O.; Ramos, Henry J.

    2012-02-01

    The efficacy of chemical and plasma treatments with phosphate and boric compounds, and nitrogen as flame retardants on wood are compared in this study. The chemical treatment involved the conventional method of spraying the solution over the wood surface at atmospheric condition and chemical vapor deposition in a vacuum chamber. The plasma treatment utilized a dielectric barrier discharge ionizing and decomposing the flame retardants into innocuous simple compounds. Wood samples are immersed in either phosphoric acid, boric acid, hydrogen or nitrogen plasmas or a plasma admixture of two or three compounds at various concentrations and impregnated by the ionized chemical reactants. Chemical changes on the wood samples were analyzed by Fourier transform infrared spectroscopy (FTIR) while the thermal changes through thermo gravimetric analysis (TGA). Plasma-treated samples exhibit superior thermal stability and fire retardant properties in terms of highest onset temperature, temperature of maximum pyrolysis, highest residual char percentage and comparably low total percentage weight loss.

  17. Pollutant emissions during the pyrolysis and combustion of flexible polyurethane foam.

    PubMed

    Garrido, María A; Font, Rafael; Conesa, Juan A

    2016-06-01

    Thermal decomposition of flexible polyurethane foam (FPUF) was studied under nitrogen and air atmospheres at 550°C and 850°C using a laboratory scale reactor to analyse the evolved products. Ammonia, hydrogen cyanide and nitrile compounds were obtained in high yields in pyrolysis at the lower temperature, whereas at 850°C polycyclic aromatic hydrocarbons (PAHs) and other semivolatile compounds, especially compounds containing nitrogen (benzonitrile, aniline, quinolone and indene) were the most abundant products. Different behaviour was observed in the evolution of polychlorodibenzo-p-dioxins and furans (PCDD/Fs) at 550°C and 850°C. At 550°C, the less chlorinated congeners, mainly PCDF, were more abundant. Contrarily, at 850°C the most chlorinated PCDD were dominant. In addition, the total yields of PCDD/Fs in the pyrolysis and combustion runs at 850°C were low and quite similar. Copyright © 2016 Elsevier Ltd. All rights reserved.

  18. Recent advance in oxazole-based medicinal chemistry.

    PubMed

    Zhang, Hui-Zhen; Zhao, Zhi-Long; Zhou, Cheng-He

    2018-01-20

    Oxazole compounds containing nitrogen and oxygen atoms in the five-membered aromatic ring are readily able to bind with a variety of enzymes and receptors in biological systems via diverse non-covalent interactions, and thus display versatile biological activities. The related researches in oxazole-based derivatives including oxazoles, isoxazoles, oxazolines, oxadiazoles, oxazolidones, benzoxazoles and so on, as medicinal drugs have been an extremely active topic, and numerous excellent achievements have been acquired. Noticeably, a large number of oxazole compounds as clinical drugs or candidates have been frequently employed for the treatment of various types of diseases, which have shown their large development value and wide potential as medicinal agents. This work systematically reviewed the recent researches and developments of the whole range of oxazole compounds as medicinal drugs, including antibacterial, antifungal, antiviral, antitubercular, anticancer, anti-inflammatory and analgesic, antidiabetic, antiparasitic, anti-obesitic, anti-neuropathic, antioxidative as well as other biological activities. The perspectives of the foreseeable future in the research and development of oxazole-based compounds as medicinal drugs are also presented. It is hoped that this review will serve as a stimulant for new thoughts in the quest for rational designs of more active and less toxic oxazole medicinal drugs. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

  19. Is nitrogen the next carbon?

    NASA Astrophysics Data System (ADS)

    Battye, William; Aneja, Viney P.; Schlesinger, William H.

    2017-09-01

    Just as carbon fueled the Industrial Revolution, nitrogen has fueled an Agricultural Revolution. The use of synthetic nitrogen fertilizers and the cultivation of nitrogen-fixing crops both expanded exponentially during the last century, with most of the increase occurring after 1960. As a result, the current flux of reactive, or fixed, nitrogen compounds to the biosphere due to human activities is roughly equivalent to the total flux of fixed nitrogen from all natural sources, both on land masses and in the world's oceans. Natural fluxes of fixed nitrogen are subject to very large uncertainties, but anthropogenic production of reactive nitrogen has increased almost fivefold in the last 60 years, and this rapid increase in anthropogenic fixed nitrogen has removed any uncertainty on the relative importance of anthropogenic fluxes to the natural budget. The increased use of nitrogen has been critical for increased crop yields and protein production needed to keep pace with the growing world population. However, similar to carbon, the release of fixed nitrogen into the natural environment is linked to adverse consequences at local, regional, and global scales. Anthropogenic contributions of fixed nitrogen continue to grow relative to the natural budget, with uncertain consequences.

  20. Nitrogen recycling from fuel-extracted algal biomass: residuals as the sole nitrogen source for culturing Scenedesmus acutus.

    PubMed

    Gu, Huiya; Nagle, Nick; Pienkos, Philip T; Posewitz, Matthew C

    2015-05-01

    In this study, the reuse of nitrogen from fuel-extracted algal residues was investigated. The alga Scenedesmus acutus was found to be able to assimilate nitrogen contained in amino acids, yeast extracts, and proteinaceous alga residuals. Moreover, these alternative nitrogen resources could replace nitrate in culturing media. The ability of S. acutus to utilize the nitrogen remaining in processed algal biomass was unique among the promising biofuel strains tested. This alga was leveraged in a recycling approach where nitrogen is recovered from algal biomass residuals that remain after lipids are extracted and carbohydrates are fermented to ethanol. The protein-rich residuals not only provided an effective nitrogen resource, but also contributed to a carbon "heterotrophic boost" in subsequent culturing, improving overall biomass and lipid yields relative to the control medium with only nitrate. Prior treatment of the algal residues with Diaion HP20 resin was required to remove compounds inhibitory to algal growth. Copyright © 2014 Elsevier Ltd. All rights reserved.

  1. 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.

  2. Nitrogen, Aerosol Composition, and Halogens on a Tall Tower (NACHTT): Overview of a wintertime air chemistry field study in the front range urban corridor of Colorado

    NASA Astrophysics Data System (ADS)

    Brown, Steven S.; Thornton, Joel A.; Keene, William C.; Pszenny, Alexander A. P.; Sive, Barkley C.; Dubé, William P.; Wagner, Nicholas L.; Young, Cora J.; Riedel, Theran P.; Roberts, James M.; VandenBoer, Trevor C.; Bahreini, Roya; Öztürk, Fatma; Middlebrook, Ann M.; Kim, Saewung; Hübler, Gerhard; Wolfe, Daniel E.

    2013-07-01

    The Nitrogen, Aerosol Composition, and Halogens on a Tall Tower (NACHTT) field experiment took place during late winter, 2011, at a site 33 km north of Denver, Colorado. The study included fixed-height measurements of aerosols, soluble trace gases, and volatile organic compounds near surface level, as well as vertically resolved measurements of nitrogen oxides, aerosol composition, soluble gas-phase acids, and halogen species from 3 to 270 m above ground level. There were 1928 individual profiles during the three-week campaign to characterize trace gas and aerosol distributions in the lower levels of the boundary layer. Nitrate and ammonium dominated the ionic composition of aerosols and originated primarily from local or regional sources. Sulfate and organic matter were also significant and were associated primarily with longer-range transport to the region. Aerosol chloride was associated primarily with supermicron size fractions and was always present in excess of gas-phase chlorine compounds. The nighttime radical reservoirs, nitryl chloride, ClNO2, and nitrous acid, HONO, were both consistently present in nighttime urban air. Nitryl chloride was especially pronounced in plumes from large point sources sampled aloft at night. Nitrous acid was typically most concentrated near the ground surface and was the dominant contributor (80%) to diurnally averaged primary OH radical production in near-surface air. Large observed mixing ratios of light alkanes, both in near-surface air and aloft, were attributable to local emissions from oil and gas activities.

  3. Wet and dry nitrogen deposition in the central Sichuan Basin of China

    NASA Astrophysics Data System (ADS)

    Kuang, Fuhong; Liu, Xuejun; Zhu, Bo; Shen, Jianlin; Pan, Yuepeng; Su, Minmin; Goulding, Keith

    2016-10-01

    Reactive nitrogen (Nr) plays a key role in the atmospheric environment and its deposition has induced large negative impacts on ecosystem health and services. Five-year continuous in-situ monitoring of N deposition, including wet (total nitrogen (WTN), total dissolved nitrogen (WTDN), dissolved organic nitrogen (WDON), ammonium nitrogen (WAN) and nitrate nitrogen (WNN)) and dry (DNH3, DHNO3, DpNH4+, DpNO3- and DNO2) deposition, had been conducted since August 2008 to December 2013 (wet) and May 2011 to December 2013 (dry) in Yan-ting, China, a typical agricultural area in the central Sichuan Basin. Mean annual total N deposition from 2011 to 2013 was 30.8 kg N ha-1 yr-1, and speculated that of 2009 and 2010 was averaged 28.2 kg N ha-1 yr-1, respectively. Wet and dry N deposition accounted for 76.3% and 23.7% of annual N deposition, respectively. Reduced N (WAN, DNH3 and DpNH4+) was 1.7 times of oxidized N (WNN, DHNO3, DNO2 and DpNO3-) which accounted for 50.9% and 30.3% of TN, respectively. Maximum loadings of all N forms of wet deposition, gaseous NH3, HNO3 and particulate NH4+ in dry deposition occurred in summer and minimum loadings in winter. Whether monthly, seasonal or annual averaged, dissolved N accounted for more than 70% of the total. N deposition in the central Sichuan Basin increased during the sampling period, especially that of ammonium compounds, and has become a serious threat to local aquatic ecosystems, the surrounding forest and other natural or semi-natural ecosystems in the upper reaches of the Yangtze River.

  4. Factors Controlling the Stable Nitrogen Isotopic Composition (δ15N) of Lipids in Marine Animals

    PubMed Central

    Svensson, Elisabeth; Schouten, Stefan; Hopmans, Ellen C.; Middelburg, Jack J.; Sinninghe Damsté, Jaap S.

    2016-01-01

    Lipid extraction of biomass prior to stable isotope analysis is known to cause variable changes in the stable nitrogen isotopic composition (δ15N) of residual biomass. However, the underlying factors causing these changes are not yet clear. Here we address this issue by comparing the δ15N of bulk and residual biomass of several marine animal tissues (fish, crab, cockle, oyster, and polychaete), as well as the δ15N of the extracted lipids. As observed previously, lipid extraction led to a variable offset in δ15N of biomass (differences ranging from -2.3 to +1.8 ‰). Importantly, the total lipid extract (TLE) was highly depleted in 15N compared to bulk biomass, and also highly variable (differences ranging from -14 to +0.7 ‰). The TLE consisted mainly of phosphatidylcholines, a group of lipids with one nitrogen atom in the headgroup. To elucidate the cause for the 15N-depletion in the TLE, the δ15N of amino acids was determined, including serine because it is one of the main sources of nitrogen to N-containing lipids. Serine δ15N values differed by -7 to +2 ‰ from bulk biomass δ15N, and correlated well with the 15N depletion in TLEs. On average, serine was less depleted (-3‰) than the TLE (-7 ‰), possibly due to fractionation during biosynthesis of N-containing headgroups, or that other nitrogen-containing compounds, such as urea and choline, or recycled nitrogen contribute to the nitrogen isotopic composition of the TLE. The depletion in 15N of the TLE relative to biomass increased with the trophic level of the organisms. PMID:26731720

  5. Denitrification likely catalyzed by endobionts in an allogromiid foraminifer

    PubMed Central

    Bernhard, Joan M; Edgcomb, Virginia P; Casciotti, Karen L; McIlvin, Matthew R; Beaudoin, David J

    2012-01-01

    Nitrogen can be a limiting macronutrient for carbon uptake by the marine biosphere. The process of denitrification (conversion of nitrate to gaseous compounds, including N2 (nitrogen gas)) removes bioavailable nitrogen, particularly in marine sediments, making it a key factor in the marine nitrogen budget. Benthic foraminifera reportedly perform complete denitrification, a process previously considered nearly exclusively performed by bacteria and archaea. If the ability to denitrify is widespread among these diverse and abundant protists, a paradigm shift is required for biogeochemistry and marine microbial ecology. However, to date, the mechanisms of foraminiferal denitrification are unclear, and it is possible that the ability to perform complete denitrification is because of the symbiont metabolism in some foraminiferal species. Using sequence analysis and GeneFISH, we show that for a symbiont-bearing foraminifer, the potential for denitrification resides in the endobionts. Results also identify the endobionts as denitrifying pseudomonads and show that the allogromiid accumulates nitrate intracellularly, presumably for use in denitrification. Endobionts have been observed within many foraminiferal species, and in the case of associations with denitrifying bacteria, may provide fitness for survival in anoxic conditions. These associations may have been a driving force for early foraminiferal diversification, which is thought to have occurred in the Neoproterozoic era when anoxia was widespread. PMID:22134648

  6. Heterogeneous Atmospheric Chemistry of Lead Oxide Particles with Nitrogen Dioxide Increases Lead Solubility: Environmental and Health Implications

    PubMed Central

    Baltrusaitis, Jonas; Chen, Haihan; Rubasinghege, Gayan

    2012-01-01

    Heterogeneous chemistry of nitrogen dioxide with lead-containing particles is investigated to better understand lead metal mobilization in the environment. In particular, PbO particles, a model lead-containing compound due to its wide spread presence as a component of lead paint and as naturally occurring minerals, massicot and litharge, are exposed to nitrogen dioxide at different relative humidity. X-ray photoelectron spectroscopy (XPS) shows that upon exposure to nitrogen dioxide the surface of PbO particles react to form adsorbed nitrates and lead nitrate thin films with the extent of formation of nitrate relative humidity dependent. Surface adsorbed nitrate increases the amount of dissolved lead. These reacted particles are found to have an increase in the amount of lead that dissolves in aqueous suspensions at circumneutral pH compared to unreacted particles. These results point to the potential importance and impact that heterogeneous chemistry with trace atmospheric gases can have on increasing solubility and therefore the mobilization of heavy metals, such as lead, in the environment. This study also show that surface intermediates, such as adsorbed nitrates, that form can yield higher concentrations of lead in water systems. In the environment, these water systems can include drinking water, ground water, estuaries and lakes. PMID:23057678

  7. Genotypic Tannin Levels in Populus tremula Impact the Way Nitrogen Enrichment Affects Growth and Allocation Responses for Some Traits and Not for Others

    PubMed Central

    Bandau, Franziska; Decker, Vicki Huizu Guo; Gundale, Michael J.; Albrectsen, Benedicte Riber

    2015-01-01

    Plant intraspecific variability has been proposed as a key mechanism by which plants adapt to environmental change. In boreal forests where nitrogen availability is strongly limited, nitrogen addition happens indirectly through atmospheric N deposition and directly through industrial forest fertilization. These anthropogenic inputs of N have numerous environmental consequences, including shifts in plant species composition and reductions in plant species diversity. However, we know less about how genetic differences within plant populations determine how species respond to eutrophication in boreal forests. According to plant defense theories, nitrogen addition will cause plants to shift carbon allocation more towards growth and less to chemical defense, potentially enhancing vulnerability to antagonists. Aspens are keystone species in boreal forests that produce condensed tannins to serve as chemical defense. We conducted an experiment using ten Populus tremula genotypes from the Swedish Aspen Collection that express extreme levels of baseline investment into foliar condensed tannins. We investigated whether investment into growth and phenolic defense compounds in young plants varied in response to two nitrogen addition levels, corresponding to atmospheric N deposition and industrial forest fertilization. Nitrogen addition generally caused growth to increase, and tannin levels to decrease; however, individualistic responses among genotypes were found for height growth, biomass of specific tissues, root:shoot ratios, and tissue lignin and N concentrations. A genotype’s baseline ability to produce and store condensed tannins also influenced plant responses to N, although this effect was relatively minor. High-tannin genotypes tended to grow less biomass under low nitrogen levels and more at the highest fertilization level. Thus, the ability in aspen to produce foliar tannins is likely associated with a steeper reaction norm of growth responses, which suggests a higher plasticity to nitrogen addition, and potentially an advantage when adapting to higher concentrations of soil nitrogen. PMID:26488414

  8. Genotypic Tannin Levels in Populus tremula Impact the Way Nitrogen Enrichment Affects Growth and Allocation Responses for Some Traits and Not for Others.

    PubMed

    Bandau, Franziska; Decker, Vicki Huizu Guo; Gundale, Michael J; Albrectsen, Benedicte Riber

    2015-01-01

    Plant intraspecific variability has been proposed as a key mechanism by which plants adapt to environmental change. In boreal forests where nitrogen availability is strongly limited, nitrogen addition happens indirectly through atmospheric N deposition and directly through industrial forest fertilization. These anthropogenic inputs of N have numerous environmental consequences, including shifts in plant species composition and reductions in plant species diversity. However, we know less about how genetic differences within plant populations determine how species respond to eutrophication in boreal forests. According to plant defense theories, nitrogen addition will cause plants to shift carbon allocation more towards growth and less to chemical defense, potentially enhancing vulnerability to antagonists. Aspens are keystone species in boreal forests that produce condensed tannins to serve as chemical defense. We conducted an experiment using ten Populus tremula genotypes from the Swedish Aspen Collection that express extreme levels of baseline investment into foliar condensed tannins. We investigated whether investment into growth and phenolic defense compounds in young plants varied in response to two nitrogen addition levels, corresponding to atmospheric N deposition and industrial forest fertilization. Nitrogen addition generally caused growth to increase, and tannin levels to decrease; however, individualistic responses among genotypes were found for height growth, biomass of specific tissues, root:shoot ratios, and tissue lignin and N concentrations. A genotype's baseline ability to produce and store condensed tannins also influenced plant responses to N, although this effect was relatively minor. High-tannin genotypes tended to grow less biomass under low nitrogen levels and more at the highest fertilization level. Thus, the ability in aspen to produce foliar tannins is likely associated with a steeper reaction norm of growth responses, which suggests a higher plasticity to nitrogen addition, and potentially an advantage when adapting to higher concentrations of soil nitrogen.

  9. 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.

  10. [Features of the biochemical action of paraquat on oxidative deamination of biogenic amines and other nitrogen compounds].

    PubMed

    Amanov, K; Mamadiev, M; Khuzhamberdiev, M A; Gorkin, V Z

    1994-01-01

    Intoxication of rats with the herbicide paraquat (1,1-dimethyl-4,4-bipyridilium dichloride) was accompanied by accumulation in lungs, brain, heart, liver or kidney of malonic dialdehyde (MDA) (the compounds reacting with 2-thiobarbituric acid), indicating that the intoxication stimulated lipid peroxidation (LPO) in biomembranes. Treatment of the intoxicated rats with the antioxidant diludin (2,6-dimethyl-3,5-diethoxycarbonyl-1,4-dihydropyridine) or with the nucleophilic reagents sodium ascorbate or thiosulphate normalized the content of MDA in lungs, brain, heart, liver or kidney demonstrating the reversibility of the LPO stimulation caused by paraquat. On incubation of mitochondrial fractions of homogenates of lungs, brain, heart, liver or kidney of the intoxicated rats (as compared with the corresponding fractions from the intact animals) a decrease was noted in deamination of the substrates of monoamine oxidases serotonin, tryptamine, benzylamine, tyramine; at the same time, deamination of glucosamine and gamma-aminobutyric acid was increased and deamination of putrescine and L-lysine appeared. These impairments in deamination of nitrogenous compounds caused by paraquat were reversible. All the impairments were normalized by the treatment of the experimental animals with the antioxidative and nucleophilic reagents; a decrease was noted in the rate of development of the lethal paraquat intoxication and appearance of morphological manifestations of normalization. The data obtained suggest that the reversible, qualitative modification ("transformation") of the monoamine oxidases of the type A might explain the peculiarities of the alterations in deamination of nitrogenous compounds in paraquat intoxication.

  11. Theoretical study of the alkaline hydrolysis of an aza-β-lactam derivative of clavulanic acid

    NASA Astrophysics Data System (ADS)

    Garcías, Rafael C.; Coll, Miguel; Donoso, Josefa; Muñoz, Francisco

    2003-04-01

    DFT calculations based on the hybrid functional B3LYP/6-31+G * were used to study the alkaline hydrolysis of an aza-clavulanic acid, which results from the substitution of the carbon atom at position 6 in clavulanic acid by a nitrogen atom. The presence of the nitrogen atom endows the compound with special properties; in fact, once formed, the tetrahedral intermediate can evolve with cleavage of the N 4-C 7 or N 6-C 7 bond, which obviously leads to different reaction products. These differential bond cleavages may play a central role in the inactivation of β-lactamases, so the compound may be a powerful inactivator of these enzymes.

  12. [Nitrous compound content in the tissues of the cerebral hemispheres and cerebellum of rats after a flight on the Kosmos-1129 biosatellite].

    PubMed

    Kurkina, L M; Tigranian, R A

    1982-01-01

    The content of ammonia, glutamine, urea, glutamic acid, aspartic acid, and GABA was measured to study nitrogen metabolism. Soon after recovery (6-10 hours after recovery) the content of the above compounds in brain tissues increased, except for GABA whose content decreased. Similar but more marked changes were seen in the brain of control rats exposed to a repeated immobilization stress-effect. These changes were still greater in the flight rats exposed to a repeated immobilization stress-effect postflight. It is suggested that the postflight changes of the above parameters of nitrogen metabolism are induced by stress-agents inherent in space flight and recovery.

  13. Will more nitrogen enhance carbon storage in young forest stands in central Appalachia?

    Treesearch

    Zachariah K. Fowler; Mary Beth Adams; William T. Peterjohn

    2015-01-01

    Many temperate deciduous forests in the Eastern US are secondary, regrowing forests and have experienced decades of elevated inputs of acidic compounds and biologically available nitrogen (N) from the atmosphere. These young forests play an important role in the global carbon (C) cycle as C sinks, and it is possible that acidic deposition will influence the strength...

  14. Lattice Gas Model Based Optimization of Plasma-Surface Processes for GaN-Based Compound Growth

    NASA Astrophysics Data System (ADS)

    Nonokawa, Kiyohide; Suzuki, Takuma; Kitamori, Kazutaka; Sawada, Takayuki

    2001-10-01

    Progress of the epitaxial growth technique for GaN-based compounds makes these materials attractive for applications in high temperature/high-power electronic devices as well as in short-wavelength optoelectronic devices. For MBE growth of GaN epilayer, atomic nitrogen is usually supplied from ECR-plasma while atomic Ga is supplied from conventional K-cell. To grow high-quality epilayer, fundamental knowledge of the detailed atomic process, such as adsorption, surface migration, incorporation, desorption and so forth, is required. We have studied the influence of growth conditions on the flatness of the growth front surface and the growth rate using Monte Carlo simulation based on the lattice gas model. Under the fixed Ga flux condition, the lower the nitrogen flux and/or the higher the growth temperature, the better the flatness of the front surface at the sacrifice of the growth rate of the epilayer. When the nitrogen flux is increased, the growth rate reaches saturation value determined from the Ga flux. At a fixed growth temperature, increasing of nitrogen to Ga flux ratio results in rough surface owing to 3-dimensional island formation. Other characteristics of MBE-GaN growth using ECR-plasma can be well reproduced.

  15. 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.

  16. Effect of reduced industrial pumpage on the migration of dissolved nitrogen in an outwash aquifer at Olean, Cattaraugus County, New York

    USGS Publications Warehouse

    Bergeron, M.P.

    1987-01-01

    A quasi-three-dimensional digital groundwater flow model of a shallow outwash aquifer system at Olean, New York, was developed to study the effects of several pumping alternatives on groundwater flow and stream seepage. Nitrogen compounds have contaminated the aquifer in an industrial park in North Olean. Pumping from seven industrial production wells and a purge well has created a cone of depression within which all nitrogen compounds are contained, thus preventing their migration to nearby private, municipal, and industrial-supply wells. A simulated total shutdown of an industrial well field and the purge well indicates that groundwater flowing laterally southward to southwestward from the area of contamination would require about 5 yr to reach a municipal well field along the Allegheny River. Simulation of a partial shutdown with only three main production wells and the purge well or just the three production wells indicate that all nitrogen-bearing groundwater would be captured. Pumping from only the purge well would allow contaminated groundwater along the southwestern edge of the site to escape and, in 8 to 9 yr, reach the municipal well field. (USGS)

  17. 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. Copyright © 2013 Elsevier Ltd. All rights reserved.

  18. Tracking changes in composition and amount of dissolved organic matter throughout drinking water treatment plants by comprehensive two-dimensional gas chromatography-quadrupole mass spectrometry.

    PubMed

    Li, Chunmei; Wang, Donghong; Xu, Xiong; Xu, Meijia; Wang, Zijian; Xiao, Ruiyang

    2017-12-31

    Dissolved organic matter (DOM) can affect the performance of water treatment processes and produce undesirable disinfection by-products during disinfection. Several studies have been undertaken on the structural characterization of DOM, but its fate during drinking water treatment processes is still not fully understood. In this work, the nontargeted screening method of comprehensive two-dimensional gas chromatography-quadrupole mass spectrometry (GC×GC-qMS) was used to reveal the detailed changes of different chemical classes of compounds in DOM during conventional and advanced drinking water treatment processes at three drinking water treatment plants in China. The results showed that when the dissolved organic carbon removal was low, shifts in the DOM composition could not be detected with the specific ultraviolet absorbance at 254nm, but the changes were clear in the three-dimensional fluorescence excitation-emission matrix or GC×GC-qMS analyses. Coagulation-sedimentation processes selectively removed 37-59% of the nitrogenous compounds, alcohols and aromatic hydrocarbons but increased the concentrations of halogen-containing compounds by 17-26% because of the contact time with chlorine in this step. Filtration was less efficient at removing DOM but preferentially removed 21-60% of the acids. However, other organic matter would be released from the filter (e.g., nitrogenous compounds, acids, and aromatic hydrocarbons). Biological activated carbon (BAC) treatment removed most of the compounds produced from ozonation, particularly ketones, alcohols, halogen-containing compounds and acids. However, it should be noted that certain highly polar or high molecular weight compounds not identified in this study might be released from the BAC bed. After the whole treatment processes, the concentrations of nitrogenous compounds, alcohols, alkenes, aromatic hydrocarbons and ketones were decreased more by the advanced treatment processes than by the conventional treatment processes. Alcohol and ketone removals were probably related to the reduction in protein-like materials. Alkane removal was probably related to the reduction in fulvic acid-like and humic acid-like materials. Copyright © 2017 Elsevier B.V. All rights reserved.

  19. Specificity of the Antibody Receptor Site to D-Lysergamide: Model of a Physiological Receptor for Lysergic Acid Diethylamide

    PubMed Central

    Vunakis, Helen Van; Farrow, John T.; Gjika, Hilda B.; Levine, Lawrence

    1971-01-01

    Antibodies to D-lysergic acid have been produced in rabbits and guinea pigs and a radioimmunoassay for the hapten was developed. The specificity of this lysergamide-antilysergamide reaction was determined by competitive binding with unlabeled lysergic acid diethylamide (LSD), psychotomimetic drugs, neurotransmitters, and other compounds with diverse structures. LSD and several related ergot alkaloids were potent competitors, three to seven times more potent than lysergic acid itself. The N,N-dimethyl derivatives of several compounds, including tryptamine, 5-hydroxytryptamine, 4-hydroxytryptamine, 5-methoxytryptamine, tyramine, and mescaline, were only about ten times less effective than lysergic acid, even though these compounds lack some of the ring systems of lysergic acid. The pattern of inhibition by related compounds with various substituents suggests that the antibody receptor site recognizes structural features resembling the LSD molecule. In particular, the aromatic nucleus and the dimethylated ethylamine side chain in phenylethylamine and tryptamine derivatives may assume in solution a conformation resembling ring A and the methylated nitrogen in ring C of LSD. Among the tryptamine derivatives, a large percentage of the most potent competitors are also psychotomimetic compounds. PMID:5283939

  20. Quantitative Characterization of Aqueous Byproducts from Hydrothermal Liquefaction of Municipal Wastes, Food Industry Wastes, and Biomass Grown on Waste

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Maddi, Balakrishna; Panisko, Ellen; Wietsma, Thomas

    Hydrothermal liquefaction (HTL) is a viable thermochemical process for converting wet solid wastes into biocrude which can be hydroprocessed to liquid transportation fuel blendstocks and specialty chemicals. The aqueous byproduct from HTL contains significant amounts (20 to 50%) of the feed carbon, which must be used to enhance economic sustainability of the process on an industrial scale. In this study, aqueous fractions produced from HTL of industrial and municipal waste were characterized using a wide variety of analytical approaches. Organic chemical compounds present in these aqueous fractions were identified using two-dimensional gas chromatography equipped with time-of-flight mass spectrometry. Identified compoundsmore » include organic acids, nitrogen compounds, alcohols, aldehydes, and ketones. Conventional gas chromatography and liquid chromatography methods were employed to quantify the identified compounds. Inorganic species, in the aqueous stream of hydrothermal liquefaction of these aqueous byproducts, also were quantified using ion chromatography and inductively coupled plasma optical emission spectroscopy. The concentrations of organic chemical compounds and inorganic species are reported, and the significance of these results is discussed in detail.« less

  1. Removal of nitrogen oxides from gas streams by biofiltration

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Barrett, K.B.; Barnes, J.M.; Apel, W.A.

    1994-12-31

    Nitrogen oxides (NO{sub x}) are primary air pollutants and, as such, there is considerable interest in the development of efficient, cost effective technologies to remediate NO{sub x} containing emissions. Biofiltration involves the venting of contaminated gas streams through biologically active material such as soil or compost. This technology has been used successfully to control odors as well as volatile organic compounds from a variety of industrial and public sources. The purpose of this study was to evaluate the feasibility of using biofiltration to convert NO{sub x} to nitrogen gas.

  2. Populations of Pratylenchus penetrans Relative to Decomposing Nitrogenous Soil Amendments

    PubMed Central

    Walker, J. T.

    1971-01-01

    Populations of Pratylenchus penetrans decreased in soil following addition of 70 and 700 ppm N in the form of nitrate, nitrite, organic nitrogen, or ammonium compounds. Nitrate was less effective than other nitrogen carriers. Population reduction is principally attributed to ammonification during decomposition. This hypothesis is supported by chromatographic analyses of soil atmospheres, survival of nematodes in pure CO₂ and N₂, inverse relationship of CO₂, content in amended soils to nematode populations, and direct relationship of NH₃-N content of amended soils to nematode populations. PMID:19322339

  3. Chemical Characteristics of Organic Aerosols in Shanghai: A Study by Ultrahigh-Performance Liquid Chromatography Coupled With Orbitrap Mass Spectrometry

    NASA Astrophysics Data System (ADS)

    Wang, Xinke; Hayeck, Nathalie; Brüggemann, Martin; Yao, Lei; Chen, Hangfei; Zhang, Ci; Emmelin, Corinne; Chen, Jianmin; George, Christian; Wang, Lin

    2017-11-01

    Particulate matter 2.5 (PM2.5) filter samples were collected in July and October 2014 and January and April 2015 in urban Shanghai and analyzed using ultrahigh-performance liquid chromatography coupled to Orbitrap mass spectrometry. The measured chromatogram-mass spectra were processed by a nontarget screening approach to identify significant signals. In total, 810-1,510 chemical formulas of organic compounds in the negative polarity (negative electrospray ionization (ESI-)) and 860-1,790 in the positive polarity (ESI+), respectively, were determined. The chemical characteristics of organic aerosols (OAs) in Shanghai varied among different months and between daytime and nighttime. In the January samples, organics were generally richer in terms of both number and abundance, whereas those in the July samples were far lower. More CHO- (compounds containing only carbon, hydrogen, and oxygen and detected in ESI-) and CHOS- (sulfur-containing organics) were found in the daytime samples, suggesting a photochemical source, whereas CHONS- (nitrogen- and sulfur-containing organics) were more abundant in the nighttime samples, due to nocturnal nitrate radical chemistry. A significant number of monocyclic and polycyclic aromatic compounds, and nitrogen- and sulfur-containing heterocyclic compounds, were detected in all samples, indicating that biomass burning and fossil fuel combustion made important contributions to the OAs in urban Shanghai. Additionally, precursor-product pair analysis indicates that the epoxide pathway is an important formation route for organosulfates observed in Shanghai. Moreover, a similar analysis suggests that 35-57% of nitrogen-containing compounds detected in ESI+ could be formed through reactions between ammonia and carbonyls. Our study presents a comprehensive overview of OAs in urban Shanghai, which helps to understand their characteristics and sources.

  4. Design of co-crystals/salts of some Nitrogenous bases and some derivatives of thiophene carboxylic acids through a combination of hydrogen and halogen bonds.

    PubMed

    Jennifer, Samson Jegan; Muthiah, Packianathan Thomas

    2014-01-01

    The utility of N-heterocyclic bases to obtain molecular complexes with carboxylic acids is well studied. Depending on the solid state interaction between the N-heterocyclic base and a carboxylic acid a variety of neutral or ionic synthons are observed. Meanwhile, pyridines and pyrimidines have been frequently chosen in the area of crystal engineering for their multipurpose functionality. HT (hetero trimers) and LHT (linear heterotetramers) are the well known synthons that are formed in the presence of pyrimidines and carboxylic acids. Fourteen crystals involving various substituted thiophene carboxylic acid derivatives and nitrogenous bases were prepared and characterized by using single crystal X-ray diffraction. The 14 crystals can further be divided into two groups [1a-7a], [8b-14b] based on the nature of the nitrogenous base. Carboxylic acid to pyridine proton transfer has occurred in 3 compounds of each group. In addition to the commonly occurring hydrogen bond based pyridine/carboxylic acid and pyrimidine/carboxylic acid synthons which is the reason for assembly of primary motifs, various other interactions like Cl…Cl, Cl…O, C-H…Cl, C-H…S add additional support in organizing these supermolecules into extended architectures. It is also interesting to note that in all the compounds π-π stacking occurs between the pyrimidine-pyrimidine or pyridine-pyridine or acid-acid moieties rather than acid-pyrimidine/pyridine. In all the compounds (1a-14b) either neutral O-H…Npyridyl/pyrimidine or charge-assisted Npyridinium-H…Ocarboxylate hydrogen bonds are present. The HT (hetero trimers) and LHT (linear heterotetramers) are dominant in the crystal structures of the adducts containing N-heterocyclic bases with two proton acceptors (1a-7a). Similar type supramolecular ladders are observed in 5TPC44BIPY (8b), TPC44BIPY (9b), TPC44TMBP (11b). Among the seven compounds [8b-14b] the extended ligands are linear in all except for the TMBP (10b, 11b, 12b). The structure of each compound depends on the dihedral angle between the carboxyl group and the nitrogenous base. All these compounds indicate three main synthons that regularly occur, namely linear heterodimer (HD), heterotrimer (HT) and heterotetramer (LHT).

  5. Molecular Basis of Microbial One-Carbon Metabolism 2008 Gordon Research Conference (July 20-25, 2008)

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Stephen W. Ragsdale

    2009-08-12

    One-carbon (C-1) compounds play a central role in microbial metabolism. C-1 compounds include methane, carbon monoxide, CO2, and methanol as well as coenzyme-bound one-carbon compounds (methyl-B12, CH3-H4folate, etc). Such compounds are of broad global importance because several C-1 compounds (e.g., CH4) are important energy sources, some (e.g., CO2 and CH4) are potent greenhouse gases, and others (e.g., CH2Cl2) are xenobiotics. They are central in pathways of energy metabolism and carbon fixation by microbes and many are of industrial interest. Research on the pathways of one-carbon metabolism has added greatly to our understanding of evolution, structural biology, enzyme mechanisms, gene regulation,more » ecology, and applied biology. The 2008 meeting will include recent important findings in the following areas: (a) genomics, metagenomics, and proteomic studies that have expanded our understanding of autotrophy and C-1 metabolism and the evolution of these pathways; (b) redox regulation of carbon cycles and the interrelationship between the carbon cycle and other biogeochemical cycles (sulfur, nitrogen, oxygen); (c) novel pathways for carbon assimilation; (d) biotechnology related to C-1 metabolism; (e) novel enzyme mechanisms including channeling of C-1 intermediates during metabolism; and (f) the relationship between metal homeostasis and the global carbon cycle. The conference has a diverse and gender-balanced slate of speakers and session leaders. The wide variety of disciplines brought to the study of C-1 metabolism make the field an excellent one in which to train young researchers.« less

  6. How intensive agriculture affects surface-atmosphere exchange of nitrogen and carbon compounds over peatland

    NASA Astrophysics Data System (ADS)

    Bruemmer, C.; Richter, U.; Schrader, F.; Hurkuck, M.; Kutsch, W. L.

    2016-12-01

    Mid-latitude peatlands are often exposed to high atmospheric nitrogen deposition when located in close vicinity to agricultural land. As the impacts of altered deposition rates on nitrogen-limited ecosystems are poorly understood, we investigated the surface-atmosphere exchange of several nitrogen and carbon compounds using multiple high-resolution measurement techniques and modeling. Our study site was a protected semi-natural bog ecosystem. Local wind regime and land use in the adjacent area clearly regulated whether total reactive nitrogen (∑Nr) concentrations were ammonia (NH3) or NOx-dominated. Eddy-covariance measurements of NH3 and ∑Nr revealed concentration, temperature and surface wetness-dependent deposition rates. Intermittent periods of NH3 and ∑Nr emission likely attributed to surface water re-emission and soil efflux, respectively, were found, thereby indicating nitrogen oversaturation in this originally N-limited ecosystem. Annual dry plus wet deposition resulted in 20 to 25 kg N ha-1 depending on method and model used, which translated into a four- to fivefold exceedance of the ecosystem-specific critical load. As the bog site had likely been exposed to the observed atmospheric nitrogen burden over several decades, a shift in grass species' composition towards a higher number of nitrophilous plants was already visible. Three years of CO2 eddy flux measurements showed that the site was a small net sink in the range of 33 to 268 g CO2 m-2 yr-1. Methane emissions of 32 g CO2-eq were found to partly offset the sequestered carbon through CO2. Our study demonstrates the applicability of novel micrometeorological measurement techniques in biogeochemical sciences and stresses the importance of monitoring long-term changes in vulnerable ecosystems under anthropogenic pressure and climate change.

  7. Tailoring surface and photocatalytic properties of ZnO and nitrogen-doped ZnO nanostructures using microwave-assisted facile hydrothermal synthesis

    NASA Astrophysics Data System (ADS)

    Rangel, R.; Cedeño, V.; Ramos-Corona, A.; Gutiérrez, R.; Alvarado-Gil, J. J.; Ares, O.; Bartolo-Pérez, P.; Quintana, P.

    2017-08-01

    Microwave hydrothermal synthesis, using an experimental 23 factorial design, was used to produce tunable ZnO nano- and microstructures, and their potential as photocatalysts was explored. Photocatalytic reactions were conducted in a microreactor batch system under UV and visible light irradiation, while monitoring methylene blue degradation, as a model system. The variables considered in the microwave reactor to produce ZnO nano- or microstructures, were time, NaOH concentration and synthesis temperature. It was found that, specific surface area and volume/surface area ratio were affected as a consequence of the synthesis conditions. In the second stage, the samples were plasma treated in a nitrogen atmosphere, with the purpose of introducing nitrogen into the ZnO crystalline structure. The central idea is to induce changes in the material structure as well as in its optical absorption, to make the plasma-treated material useful as photocatalyst in the visible region of the electromagnetic spectrum. Pristine ZnO and nitrogen-doped ZnO compounds were characterized by means of X-ray diffraction (XRD), scanning electron microscopy (SEM), specific surface area (BET), XPS, and UV-Vis diffuse reflectance spectroscopy. The results show that the methodology presented in this work is effective in tailoring the specific surface area of the ZnO compounds and incorporation of nitrogen into their structure, factors which in turn, affect its photocatalytic behavior.

  8. Metabolic Analysis of Adaptation to Short-Term Changes in Culture Conditions of the Marine Diatom Thalassiosira pseudonana

    PubMed Central

    Bromke, Mariusz A.; Giavalisco, Patrick; Willmitzer, Lothar; Hesse, Holger

    2013-01-01

    This report describes the metabolic and lipidomic profiling of 97 low-molecular weight compounds from the primary metabolism and 124 lipid compounds of the diatom Thalassiosira pseudonana. The metabolic profiles were created for diatoms perturbed for 24 hours with four different treatments: (I) removal of nitrogen, (II) lower iron concentration, (III) addition of sea salt, (IV) addition of carbonate to their growth media. Our results show that as early as 24 hours after nitrogen depletion significant qualitative and quantitative change in lipid composition as well as in the primary metabolism of Thalassiosira pseudonana occurs. So we can observe the accumulation of several storage lipids, namely triacylglycerides, and TCA cycle intermediates, of which citric acid increases more than 10-fold. These changes are positively correlated with expression of TCA enzymes genes. Next to the TCA cycle intermediates and storage lipid changes, we have observed decrease in N-containing lipids and primary metabolites such as amino acids. As a measure of counteracting nitrogen starvation, we have observed elevated expression levels of nitrogen uptake and amino acid biosynthetic genes. This indicates that diatoms can fast and efficiently adapt to changing environment by altering the metabolic fluxes and metabolite abundances. Especially, the accumulation of proline and the decrease of dimethylsulfoniopropionate suggest that the proline is the main osmoprotectant for the diatom in nitrogen rich conditions. PMID:23799147

  9. A Continuous Flow System for the Measurement of Ambient Nitrogen Oxides [NO + NO2] Using Rhodamine B Hydrazide as a Chemosensor

    PubMed Central

    Malingappa, Pandurangappa; Yarradoddappa, Venkataramanappa

    2014-01-01

    A new chemosensor has been used to monitor atmospheric nitrogen oxides [NO + NO2] at parts per billion (ppb) level. It is based on the catalytic reaction of nitrogen oxides with rhodamine B hydrazide (RBH) to produce a colored compound through the hydrolysis of the amide bond of the molecule. A simple colorimeter has been used to monitor atmospheric nitrogen dioxide at ppb level. The air samples were purged through a sampling cuvette containing RBH solution using peristaltic pump. The proposed method has been successfully applied to monitor the ambient nitrogen dioxide levels at traffic junction points within the city limits and the results obtained are compared with the standard Griess-Ilosvay method. PMID:25210422

  10. 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.

  11. Cable Feedthrough Between Liquid Oxygen And Ambient

    NASA Technical Reports Server (NTRS)

    Myers, Don A.

    1992-01-01

    Encapsulant and back pressure provide double protection. Cable-feedthrough tube between ambient air and interior of vessel containing liquid oxygen protects external instrumentation and cable from oxygen. Cable in tube surrounded by potting compound. Provides flow of gaseous nitrogen to dilute oxidant and makes it harmless in case of leakage through crack in potting compound.

  12. 75 FR 57390 - Approval and Promulgation of Implementation Plans; Alabama: Volatile Organic Compounds

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-09-21

    ... Tropospheric ozone, commonly known as smog, occurs when VOCs and nitrogen oxides (NO X ) react in the... contribution to tropospheric ozone formation. EPA is approving revisions to the Alabama SIP submitted on March... the VOC definition on the basis that these compounds make a negligible contribution to tropospheric...

  13. Comparing Laser Desorption Ionization and Atmospheric Pressure Photoionization Coupled to Fourier Transform Ion Cyclotron Resonance Mass Spectrometry To Characterize Shale Oils at the Molecular Level

    USGS Publications Warehouse

    Cho, Yunjo; Jin, Jang Mi; Witt, Matthias; Birdwell, Justin E.; Na, Jeong-Geol; Roh, Nam-Sun; Kim, Sunghwan

    2013-01-01

    Laser desorption ionization (LDI) coupled to Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS) was used to analyze shale oils. Previous work showed that LDI is a sensitive ionization technique for assessing aromatic nitrogen compounds, and oils generated from Green River Formation oil shales are well-documented as being rich in nitrogen. The data presented here demonstrate that LDI is effective in ionizing high-double-bond-equivalent (DBE) compounds and, therefore, is a suitable method for characterizing compounds with condensed structures. Additionally, LDI generates radical cations and protonated ions concurrently, the distribution of which depends upon the molecular structures and elemental compositions, and the basicity of compounds is closely related to the generation of protonated ions. This study demonstrates that LDI FT-ICR MS is an effective ionization technique for use in the study of shale oils at the molecular level. To the best of our knowledge, this is the first time that LDI FT-ICR MS has been applied to shale oils.

  14. The Kinetic Mechanism for Cytochrome P450 Metabolism of Type II Binding Compounds: Evidence Supporting Direct Reduction

    PubMed Central

    Pearson, Joshua; Dahal, Upendra P.; Rock, Daniel; Peng, Chi-Chi; Schenk, James O.; Joswig-Jones, Carolyn; Jones, Jeffrey P.

    2011-01-01

    The metabolic stability of a drug is an important property that should be optimized during drug design and development. Nitrogen incorporation is hypothesized to increase the stability by coordination of nitrogen to the heme iron of cytochrome P450, a binding mode that is referred to as type II binding. However, we noticed that the type II binding compound 1 has less metabolic stability at subsaturating conditions than a closely related type I binding compound 3. Three kinetic models will be presented for type II binder metabolism; 1) Dead-end type II binding, 2) a rapid equilibrium between type I and II binding modes before reduction, and 3) a direct reduction of the type II coordinated heme. Data will be presented on reduction rates of iron, the off rates of substrate (using surface plasmon resonance) and the catalytic rate constants. These data argue against the dead-end, and rapid equilibrium models, leaving the direct reduction kinetic mechanism for metabolism of the type II binding compound 1. PMID:21530484

  15. Relationship between organic precursors and N-nitrosodimethylamine (NDMA) formation in tropical water sources.

    PubMed

    Qi, Wang; Fang Yee, Lim; Jiangyong, Hu

    2014-12-01

    The presence of organic compounds in water sources is one of the concerns in water treatment. They are potential precursors of disinfection byproducts (DBPs) and thus induce health problems in humans. Among the emerging DBPs, carcinogenic compound N-nitrosodimethylamine (NDMA) has been receiving attention during the last decade. This study examined the characteristics of organic components in various water sources and investigated their relationships with NDMA formation. Experiments were carried out on selected water samples from both natural water and wastewater. Results showed similar NDMA formation kinetics for both water sources. However, more contribution of NDMA precursors was found to be from the wastewater due to its higher organic nitrogen content. NDMA formation potential (NDMAFP) of secondary effluent ranged from 264 to 530 ng/L. A correlation study between organic compound characteristics and NDMAFP indicated that the majority of NDMA precursors came from dissolved organic nitrogen (DON) compound with small molecular weight (smaller than 500 Da), with correlation R(2) = 0.898. Although secondary treatment removed more than 90% of NDMA precursors, the remaining precursors in secondary effluent would still pose a challenge for water quality.

  16. 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.

  17. Polymers incorporating covalently attached organoimido polyoxometalates

    DOEpatents

    Maatta, Eric A.; Moore, Aaron R.

    2004-03-16

    New polyoxometalate compounds and polymers comprising recurring monomers of those compounds are provided. The compounds are formed by replacing at least one oxide of the starting polyoxometalate with an organoimido (NR) group bonded to the polyoxometalate via a triple bond to the nitrogen atom. The R of the (NR) group comprises a reactive functional group which renders the compound readily polymerizable, alone or with other monomers (e.g., divinylbenzene), to form the inventive polymers. Additionally, a countercation (e.g., bis(tetra-n-butylammonium)) can be mixed with the polyoxometalate compounds in order to neutralize the negative charge thereof as well as to make those compounds more soluble in organic solvents.

  18. Generation of Maillard compounds from inulin during the thermal processing of Agave tequilana Weber Var. azul.

    PubMed

    Mancilla-Margalli, Norma A; López, Mercedes G

    2002-02-13

    During the cooking process of Agave tequilana Weber var. azul to produce tequila, besides the hydrolysis of inulin to generate fermentable sugars, many volatiles, mainly Maillard compounds, are produced, most of which may have a significant impact on the overall flavor of tequila. Exudates (agave juice) from a tequila company were collected periodically, and color, Brix, fructose concentration, and reducing sugars were determined as inulin breakdown took place. Maillard compounds were obtained by extraction with CH(2)Cl(2), and the extracts were analyzed by GC-MS. Increments in color, Brix, and reducing sugars were observed as a function of time, but a decrease in fructose concentration was found. Many Maillard compounds were identified in the exudates, including furans, pyrans, aldehydes, and nitrogen and sulfur compounds. The most abundant Maillard compounds were methyl-2-furoate, 2,3-dihydroxy-3,5-dihydro-6-methyl-4(H)-pyran-4-one, and 5-(hydroxymethyl)furfural. In addition, a series of short- and long-chain fatty acids was also found. A large number of the volatiles in A. tequilana Weber var. azul were also detected in tequila extracts, and most of these have been reported as a powerful odorants, responsible for the unique tequila flavor.

  19. Development of marine toxicity data for ordnance compounds

    USGS Publications Warehouse

    Nipper, M.; Carr, R.S.; Biedenbach, J.M.; Hooten, R.L.; Miller, K.; Saepoff, S.

    2001-01-01

    A toxicity database for ordnance compounds was generated using eight compounds of concern and marine toxicity tests with five species from different phyla. Toxicity tests and endpoints included fertilization success and embryological development with the sea urchin Arbacia punctulata; zoospore germination, germling length, and cell number with the green macroalga Ulva fasciata; survival and reproductive success of the polychaete Dinophilus gyrociliatus; larvae hatching and survival with the redfish Sciaenops ocellatus; and survival of juveniles of the opossum shrimp Americamysis bahia (formerly Mysidopsis bahia). The studied ordnance compounds were 2,4- and 2,6-dinitrotoluene, 2,4,6-trinitrotoluene, 1,3-dinitrobenzene, 1,3,5-trinitrobenzene, 2,4,6-trinitrophenylmethylnitramine (tetryl), 2,4,6-trinitrophenol (picric acid), and hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX). The most sensitive toxicity test endpoints overall were the macroalga zoospore germination and the polychaete reproduction tests. The most toxic ordnance compounds overall were tetryl and 1,3,5-trinitrobenzene. These were also the most degradable compounds, often being reduced to very low or below-detection levels at the end of the test exposure. Among the dinitro- and trinitrotoluenes and benzenes, toxicity tended to increase with the level of nitrogenation. Picric acid and RDX were the least toxic chemicals tested overall.

  20. 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.

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