Sample records for sulfur compounds sulfur

  1. Oxidation of Sulfur and Inorganic Sulfur Compounds in Acidianus ambivalens

    Microsoft Academic Search

    Arnulf Kletzin

    Mechanisms of archaeal sulfur and inorganic sulfur compound oxidation were almost exclusively studied in Acidianus species, extremely thermophilic and acidophilic (pHopt 2–3), coccoid microorganisms living in acidic volcanic environments\\u000a (solfataras) worldwide. They utilize H2, H2S, S0, polythionates, and metal sulfi des as the most important sources of metabolic\\u000a energy for CO2 fi xation during aerobic growth. The sulfur oxidation pathways

  2. Thiophenic Sulfur Compounds Released During Coal Pyrolysis.

    PubMed

    Xing, Mengwen; Kong, Jiao; Dong, Jie; Jiao, Haili; Li, Fan

    2013-06-01

    Thiophenic sulfur compounds are released during coal gasification, carbonization, and combustion. Previous studies indicate that thiophenic sulfur compounds degrade very slowly in the environment, and are more carcinogenic than polycyclic aromatic hydrocarbons and nitrogenous compounds. Therefore, it is very important to study the principle of thiophenic sulfur compounds during coal conversion, in order to control their emission and promote clean coal utilization. To realize this goal and understand the formation mechanism of thiophenic sulfur compounds, this study focused on the release behavior of thiophenic sulfur compounds during coal pyrolysis, which is an important phase for all coal thermal conversion processes. The pyrolyzer (CDS-5250) and gas chromatography-mass spectrometry (Focus GC-DSQII) were used to analyze thiophenic sulfur compounds in situ. Several coals with different coal ranks and sulfur contents were chosen as experimental samples, and thiophenic sulfur compounds of the gas produced during pyrolysis under different temperatures and heating rates were investigated. Levels of benzothiophene and dibenzothiophene were obtained during pyrolysis at temperatures ranging from 200°C to 1300°C, and heating rates ranging from 6°C/ms to 14°C/ms and 6°C/s to 14°C/s. Moreover, the relationship between the total amount of benzothiophene and dibenzothiophene released during coal pyrolysis and the organic sulfur content in coal was also discussed. This study is beneficial for understanding the formation and control of thiophenic sulfur compounds, since it provides a series of significant results that show the impact that operation conditions and organic sulfur content in coal have on the amount and species of thiophenic sulfur compounds produced during coal pyrolysis. PMID:23781126

  3. Thiophenic Sulfur Compounds Released During Coal Pyrolysis

    PubMed Central

    Xing, Mengwen; Kong, Jiao; Dong, Jie; Jiao, Haili; Li, Fan

    2013-01-01

    Abstract Thiophenic sulfur compounds are released during coal gasification, carbonization, and combustion. Previous studies indicate that thiophenic sulfur compounds degrade very slowly in the environment, and are more carcinogenic than polycyclic aromatic hydrocarbons and nitrogenous compounds. Therefore, it is very important to study the principle of thiophenic sulfur compounds during coal conversion, in order to control their emission and promote clean coal utilization. To realize this goal and understand the formation mechanism of thiophenic sulfur compounds, this study focused on the release behavior of thiophenic sulfur compounds during coal pyrolysis, which is an important phase for all coal thermal conversion processes. The pyrolyzer (CDS-5250) and gas chromatography–mass spectrometry (Focus GC-DSQII) were used to analyze thiophenic sulfur compounds in situ. Several coals with different coal ranks and sulfur contents were chosen as experimental samples, and thiophenic sulfur compounds of the gas produced during pyrolysis under different temperatures and heating rates were investigated. Levels of benzothiophene and dibenzothiophene were obtained during pyrolysis at temperatures ranging from 200°C to 1300°C, and heating rates ranging from 6°C/ms to 14°C/ms and 6°C/s to 14°C/s. Moreover, the relationship between the total amount of benzothiophene and dibenzothiophene released during coal pyrolysis and the organic sulfur content in coal was also discussed. This study is beneficial for understanding the formation and control of thiophenic sulfur compounds, since it provides a series of significant results that show the impact that operation conditions and organic sulfur content in coal have on the amount and species of thiophenic sulfur compounds produced during coal pyrolysis. PMID:23781126

  4. Reduced sulfur compound oxidation by Thiobacillus caldus.

    PubMed Central

    Hallberg, K B; Dopson, M; Lindström, E B

    1996-01-01

    The oxidation of reduced inorganic sulfur compounds was studied by using resting cells of the moderate thermophile Thiobacillus caldus strain KU. The oxygen consumption rate and total oxygen consumed were determined for the reduced sulfur compounds thiosulfate, tetrathionate, sulfur, sulfide, and sulfite in the absence and in the presence of inhibitors and uncouplers. The uncouplers 2,4-dinitrophenol and carbonyl cyanide m-chlorophenyl-hydrazone had no affect on the oxidation of thiosulfate, suggesting that thiosulfate is metabolized periplasmically. In contrast, the uncouplers completely inhibited the oxidation of tetrathionate, sulfide, sulfur, and sulfite, indicating that these compounds are metabolized in the cytoplasm of T. caldus KU. N-Ethylmaleimide inhibited the oxidation of tetrathionate and thiosulfate at the stage of elemental sulfur, while 2-heptyl-4-hydroxyquinoline-N-oxide stopped the oxidation of thiosulfate, tetrathionate, and elemental sulfur at the stage of sulfite. The following intermediates in the oxidation of the sulfur compounds were found by using uncouplers and inhibitors: thiosulfate was oxidized to tetrathionate, elemental sulfur was formed during the oxidation of tetrathionate and sulfide, and sulfite was found as an intermediate of tetrathionate and sulfur metabolism. On the basis of these data we propose a model for the metabolism of the reduced inorganic sulfur compounds by T. caldus KU. PMID:8550443

  5. Heterogeneous photocatalytic reactions of sulfur aromatic compounds.

    PubMed

    Samokhvalov, Alexander

    2011-11-18

    Sulfur aromatic compounds, such as mono-, di-, tri-, and tetraalkyl-substituted thiophene, benzothiophenes, dibenzothiophenes, are the molecular components of many fossils (petroleum, oil shale, tar sands, bitumen). Structural units of natural, cross-linked heteroaromatic polymers present in brown coals, turf, and soil are similar to those of sulfur aromatic compounds. Many sulfur aromatic compounds are found in the streams of petroleum refining and upgrading (naphthas, gas oils) and in the consumer products (gasoline, diesel, jet fuels, heating fuels). Besides fossils, the structural fragments of sulfur aromatic compounds are present in molecules of certain organic semiconductors, pesticides, small molecule drugs, and in certain biomolecules present in human body (pheomelanin pigments). Photocatalysis is the frontier area of physical chemistry that studies chemical reactions initiated by absorption of photons by photocatalysts, that is, upon electronic rather than thermal activation, under "green" ambient conditions. This review provides systematization and critical review of the fundamental chemical and physicochemical information on heterogeneous photocatalysis of sulfur aromatic compounds accumulated in the last 20-30 years. Specifically, the following topics are covered: physicochemical properties of sulfur aromatic compounds, major classes of heterogeneous photocatalysts, mechanisms and reactive intermediates of photocatalytic reactions of sulfur aromatic compounds, and the selectivity of these reactions. Quantum chemical calculations of properties and structures of sulfur aromatic compounds, their reactive intermediates, and the structure of adsorption complexes formed on the surface of the photocatalysts are also discussed. PMID:21809426

  6. Ambient Air Monitoring for Sulfur Compounds

    ERIC Educational Resources Information Center

    Forrest, Joseph; Newman, Leonard

    1973-01-01

    A literature review of analytical techniques available for the study of compounds at low concentrations points up some of the areas where further research is needed. Compounds reviewed are sulfur dioxide, sulfuric acid, ammonium sulfate and bisulfate, metal sulfates, hydrogen sulfide, and organic sulfides. (BL)

  7. Metabolic Reactions among Organic Sulfur Compounds

    NASA Technical Reports Server (NTRS)

    Schulte, M.; Rogers, K.

    2005-01-01

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

  8. Two stage sorption of sulfur compounds

    DOEpatents

    Moore, William E. (Manassas, VA)

    1992-01-01

    A two stage method for reducing the sulfur content of exhaust gases is disclosed. Alkali- or alkaline-earth-based sorbent is totally or partially vaporized and introduced into a sulfur-containing gas stream. The activated sorbent can be introduced in the reaction zone or the exhaust gases of a combustor or a gasifier. High efficiencies of sulfur removal can be achieved.

  9. Two stage sorption of sulfur compounds

    SciTech Connect

    Moore, W.E.

    1991-12-31

    A two stage method for reducing the sulfur content of exhaust gases is disclosed. Alkali- or alkaline-earth-based sorbent is totally or partially vaporized 10 and introduced into a sulfur-containing gas stream. The activated sorbent can be introduced in the reaction zone or the exhaust gases of a combustor or a gasifier. High efficiencies of sulfur removal can be achieved.

  10. MANUAL METHOD FOR MEASUREMENT OF REDUCED SULFUR COMPOUNDS

    EPA Science Inventory

    A manual method for measuring reduced sulfur compounds in Kraft pulp mill and sulfur recovery plant emissions was evaluated. The method involves removing SO2 from the gas stream (if present) with a citric acid-potassium citrate buffer, that passes reduced sulfur compounds; therma...

  11. Oxidation of Inorganic Sulfur Compounds by Obligately Organotrophic Bacteria

    Microsoft Academic Search

    D. Yu. Sorokin

    2003-01-01

    New data obtained by the author and other researchers on two different groups of obligately heterotrophic bacteria capable of inorganic sulfur oxidation are reviewed. Among culturable marine and (halo)alkaliphilic heterotrophs oxidizing sulfur compounds (thiosulfate and, much less actively, elemental sulfur and sulfide) incompletely to tetrathionate, representatives of the gammaproteobacteria, especially from the Halomonas group, dominate. Some denitrifying species from this

  12. Oxidative metabolism of inorganic sulfur compounds by bacteria

    Microsoft Academic Search

    Donovan P. Kelly; Jasvinder K. Shergill; Wei-Ping Lu; Ann P. Wood

    1997-01-01

    The history of the elucidation of the microbiology and biochemistry of the oxidation of inorganic sulfur compounds in chemolithotrophic bacteria is briefly reviewed, and the contribution of Martinus Beijerinck to the study of sulfur-oxidizing bacteria highlighted. Recent developments in the biochemistry, enzymology and molecular biology of sulfur oxidation in obligately and facultatively lithotrophic bacteria are summarized, and the existence of

  13. Sulfur cycle

    Microsoft Academic Search

    W. W. Kellogg; R. D. Cadle; E. R. Allen; A. L. Lazrus; E. A. Martell

    1972-01-01

    Even granting our uncertainties about parts of our model of the sulfur cycle, we can draw some conclusions from it. Man is now contributing about one half as much as nature to the total atmospheric burden of sulfur compounds, but by A.D. 2000 he will be contributing about as much, and in the northern hemisphere alone he will be more

  14. Stability of reduced sulfur compounds in whole air samplers

    SciTech Connect

    Tran, Q.; Tang, Y.Z. [Bovar-Concord Environmental, Toronto, Ontario (Canada)

    1994-12-31

    Reduced sulfur compounds can cause odor nuisance problems associated with kraft mill and sewage treatment operations. Accurate and reliable determination of reduced sulfur compounds is often required, but it is a challenging task due to the reactivity of reduced sulfur species and consequent difficulties in collection and storage of air samples. Several whole air samplers were evaluated for storage of reduced sulfur compounds at concentrations of 100 ppb (Tedlar bag only), 1 ppm and 100 ppm. Severe losses of H{sub 2}S and mercaptans were found in samples collected in electro-polished stainless steel canisters, although these canisters have been proven suitable for many volatile organic compounds. The losses of more volatile species were less severe than less volatile ones in Teflon vials, and glass and silanized glass bottles with Teflon-lined septum caps. In general, COS, CS{sub 2}, CH{sub 3}SCH{sub 3}, and CH{sub 3}SSCH{sub 3} were more stable than H{sub 2}S and mercaptans, and the reduced sulfur compounds were more stable in the Tedlar bag than in other sample containers.

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

    ERIC Educational Resources Information Center

    Hendrickson, James B.

    1985-01-01

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

  16. Uses of lunar sulfur

    NASA Technical Reports Server (NTRS)

    Vaniman, D.; Pettit, D.; Heiken, G.

    1992-01-01

    Sulfur and sulfur compounds have a wide range of applications for their fluid, electrical, chemical, and biochemical properties. Although known abundances on the Moon are limited (approximately 0.1 percent in mare soils), sulfur is relatively extractable by heating. Coproduction of sulfur during oxygen extraction from ilmenite-rich mare soils could yield sulfur in masses up to 10 percent of the mass of oxygen produced. Sulfur deserves serious consideration as a lunar resource.

  17. Uses of lunar sulfur

    SciTech Connect

    Vaniman, D.T.; Pettit, D.R.; Heiken, G.

    1988-01-01

    Sulfur and sulfur compounds have a wide range of applications for their fluid, electrical, chemical and biochemical properties. Although low in abundance on the Moon (/approximately/0.1% in mare soils), sulfur is surface-correlated and relatively extractable. Co-production of sulfur during oxygen extraction from ilmenite-rich soils could yield sulfur in masses up to 10% of the mass of oxygen produced. Sulfur deserves serious consideration as a lunar resource. 29 refs., 3 figs.

  18. Emission of volatile sulfur compounds from spruce trees

    SciTech Connect

    Rennenberg, H.; Huber, B.; Schroeder, P.; Stahl, K.; Haunold, W.; Georgil, H.W.; Slovik, S.; Pfanz, H. (Fraunhofer Institut fuer Atmosphaerische Umweltforschung, Garmisch-Partenkirchen (West Germany))

    1990-03-01

    Spruce (Picea abies L.) trees from the same clone were supplied with different, but low, amounts of plant available sulfate in the soil (9.7-18.1 milligrams per 100 grams of soil). Branches attached to the trees were enclosed in a dynamic gas exchange cuvette and analyzed for the emission of volatile sulfur compounds. Independent of the sulfate supply in the soil, H{sub 2}S was the predominant reduced sulfur compound continuously emitted from the branches with high rates during the day and low rates in the night. In the light, as well as in the dark, the rates of H{sub 2}S emission increased exponentially with increasing water vapor flux from the needles. Approximately 1 nanomole of H{sub 2}S was found to be emitted per mole of water. When stomata were closed completely, only minute emission of H{sub 2}S was observed. Apparently, H{sub 2}S emission from the needles is highly dependent on stromatal aperture, and permeation through the cuticle is negligible. In several experiments, small amounts of dimethylsulfide and carbonylsulfide were also detected in a portion of the samples. However, SO{sub 2} was the only sulfur compound consistently emitted from branches of spruce trees in addition to H{sub 2}S. Emission of SO{sub 2} mainly proceeded via an outburst starting before the beginning of the light period. The total amount of SO{sub 2} emitted from the needles during this outburst was correlated with the plant available sulfate in the soil. The diurnal changes in sulfur metabolism that may result in an outburst of SO{sub 2} are discussed.

  19. Removal of Sulfur Compounds from Coal by the Thermophilic Organism Sulfolobus acidocaldarius

    PubMed Central

    Kargi, Fikret; Robinson, James M.

    1982-01-01

    The thermophilic, reduced-sulfur, iron-oxidizing bacterium Sulfolobus acidocaldarius was used for the removal of sulfur compounds from coal. The inclusion of complex nutrients such as yeast extract and peptone, and chemical oxidizing agents, 0.01 M FeCl3 into leaching medium, reduced the rate and the extent of sulfur removal from coal. The rate of sulfur removal by S. acidocaldarius was strongly dependent on the sulfur content of the coal and on the total external surface area of coal particles. Approximately 96% of inorganic sulfur was removed from a 5% slurry of coal which had an initial total sulfur content of 4% and an inorganic (pyritic S and sulfate) sulfur content of 2.1%. This resulted in removal of 50% of initial total sulfur present in coal. PMID:16346112

  20. Marine acidophilic sulfur-oxidizing bacterium requiring salts for the oxidation of reduced inorganic sulfur compounds

    Microsoft Academic Search

    Kazuo Kamimura; Emi Higashino; Souichi Moriya; Tsuyoshi Sugio

    2003-01-01

    An acidophilic sulfur-oxidizing bacterium was isolated from seawater, and designated as strain SH. Strain SH was a Gram-negative, rod-shaped and motile bacterium, which had an optimum temperature and pH value for growth of 30°C and 4.0, respectively. The mol% guanine plus cytosine of the DNA was 46.0. Chemolithotrophic growth was observed with elemental sulfur and tetrathionate at pH 4.0, and

  1. The Sulfur Cycle

    ERIC Educational Resources Information Center

    Kellogg, W. W.; And Others

    1972-01-01

    A model estimating the contributions of sulfur compounds by natural and human activities, and the rate of removal of sulfur from the atmosphere, is based on a review of the existing literature. Areas requiring additional research are identified. (AL)

  2. Evaluation of different sulfur compounds in the diet of juvenile sunshine bass ( Morone chrysops ? × M. saxatilis ?)

    Microsoft Academic Search

    C. N. Keembiyehetty; D. M. Gatlin

    1995-01-01

    A semipurified basal diet with 35% crude protein, 0.38% methionine and 0.13% cystine was supplemented with different sulfur compounds to evaluate their efficacy in satisfying the total sulfur amino acid requirement of sunshine bass (Morone chrysops ? × M. saxatilis ?). A control diet was supplemented with l-methionine to meet the total sulfur amino acid requirement of sunshine bass, and

  3. Removal of sulfur compounds from combustion product exhaust

    DOEpatents

    Cheng, Dah Y. (Palo Alto, CA)

    1982-01-01

    A method and device are disclosed for removing sulfur containing contaminents from a combustion product exhaust. The removal process is carried out in two stages wherein the combustion product exhaust is dissolved in water, the water being then heated to drive off the sulfur containing contaminents. The sulfur containing gases are then resolublized in a cold water trap to form a concentrated solution which can then be used as a commercial product.

  4. [Allergy and professional exposure to sulfur compounds: questions posed].

    PubMed

    Vallon, C; Sainte-Laudy, J; Nasr, M

    1995-03-01

    We present here four cases of respiratory diseases which may be due to the exposition or to the handling of sulfur derivatives due to their professional activity. The responsibility of these compounds stands on the clinical history, biological cellular tests and for one of them on the evolution under a metabisulfite-free diet and a positive oral provocation test at 5 mg. The present economical crisis makes the patient-clinician relationship difficult, due to patients' wishing to hide their pathologies or their professional activities. PMID:7741961

  5. Effects of inorganic sulfur addition on fluxes of volatile sulfur compounds in Sphagnum peatlands

    NASA Technical Reports Server (NTRS)

    Demello, William Zamboni; Hines, Mark E.; Bayley, Suzanne E.

    1992-01-01

    Short and long-term impacts of increased S deposition on fluxes of volatile S compounds (VSC's) from Sphagnum peatlands were investigated in an artificially acidified (sulfuric and nitric acids) poor fen (Mire 239) at the Experimental Lakes Area (ELA), Ontario, Canada. Additional experiments were conducted in a poor fen (Sallie's Fen) in Barrington, NH, USA. At Mire 239, emissions of VSC's were monitored, before and after acidification, at control (unacidified) and experimental sections within two major physiographic zones of the mire (oligotrophic and minerotrophic). The experimental segments of the mire received S amendments since 1983, in amounts equivalent to the annual S deposition in the highest polluted areas of Canada and U.S. Dimethyl sulfide (DMS) was the predominant VSC released from the mire and varied largely with time and space (i.e., from 2.5 to 127 nmol/m(sup -2)h(sup -1)). Sulfur addition did not affect DMS emissions in a period of hours to a few days, although it stimulated production of DMS and MSH in the anoxic surficial regions of the peat. DMS emissions in the experimental oligotrophic segment of the mire was approximately 3-fold greater than in the control oligotrophic segment, and approximately 10-fold greater than in the minerotrophic zones. These differences could be due to a combination of differences in types of vegetation, nutritional status, and S input. At Sallie's Fen, DMS fluxes were approximately 8 times higher from a Sphagnum site than from a bare peat site. Fluxes of VSC's were not significantly affected by sulfate amendments at both sites, while DMS and MSH concentrations increases greatly with time in the top 10 cm of the peat column. Our data indicated that although Sphagnum is not the direct source of DMS released from Sphagnum peatlands, it might play a role in regulating DMS emissions to the atmosphere.

  6. Portable instrument and method for detecting reduced sulfur compounds in a gas

    DOEpatents

    Gaffney, J.S.; Kelly, T.J.; Tanner, R.L.

    1983-06-01

    A portable real time instrument for detecting concentrations in the part per billion range of reduced sulfur compounds in a sample gas. Ozonized air or oxygen and reduced sulfur compounds in a sample gas stream react to produce chemiluminescence in a reaction chamber and the emitted light is filtered and observed by a photomultiplier to detect reduced sulfur compounds. Selective response to individual sulfur compounds is achieved by varying reaction chamber temperature and ozone and sample gas flows, and by the use of either air or oxygen as the ozone source gas.

  7. Microbial cycling of volatile organic sulfur compounds in anoxic environments.

    PubMed

    Lomans, B P; Pol, A; Op den Camp, H J M

    2002-01-01

    Microbial cycling of volatile organic sulfur compounds (VOSC) is investigated due to the impact these compounds are thought to have on environmental processes like global temperature control, acid precipitation and the global sulfur cycle. Moreover, in several kinds of industries like composting plants and the paper industry VOSC are released causing odor problems. Waste streams containing these compounds must be treated in order to avoid the release of these compounds to the atmosphere. This paper describes the general mechanisms for the production and degradation of methanethiol (MT) and dimethyl sulfide (DMS), two ubiquitous VOSC in anaerobic environments. Slurry incubations indicated that methylation of sulfide and MT resulting in MT and DMS, respectively, is one of the major mechanisms for VOSC in sulfide-rich anaerobic environments. An anaerobic bacterium that is responsible for the formation of MT and DMS through the anaerobic methylation of H2S and MT was isolated from a freshwater pond after enrichment with syringate as a methyl group donating compound and sole carbon source. In spite of the continuous formation of MT and DMS, steady state concentrations are generally very low. This is due to the microbial degradation of these compounds. Experiments with sulfate-rich and sulfate-amended sediment slurries demonstrated that besides methanogens, sulfate-reducing bacteria can also degrade MT and DMS, provided that sulfate is available. A methanogen was isolated that is able to grow on DMS as the sole carbon source. A large survey of sediments slurries of various origin demonstrated that both isolates are commonly occurring inhabitants of anaerobic environments. PMID:12188577

  8. Active Microbial Sulfur Disproportionation in

    E-print Network

    Long, Bernard

    Active Microbial Sulfur Disproportionation in the Mesoproterozoic David T. Johnston,1 *. Boswell A E. Canfield5 The environmental expression of sulfur compound disproportionation has been placed sulfur isotope 33S. These measurements imply that sulfur compound disproportionation was an active part

  9. Sorption properties of various adsorbents for sulfur compounds in a jet fuel cut

    Microsoft Academic Search

    R. Makhlitt; A. G. Sardanashvili

    1975-01-01

    The adsorption capacity, sorption rate, and diffusivity of silica gel, aluminosilicate, and zeolite adsorbents for the removal of sulfur compounds from jet fuel was examined. A silica gel adsorbent showed the greatest adsorption capacity for sulfur compounds in a 140 to 280°C cut from Romashkino crude. Aluminosilicate adsorbent was next in adsorption capacity, followed by zeolite. However, zeolite showed a

  10. Separation of Sulfur Compounds from a Diesel Fraction by Ligand Exchange Chromatography

    Microsoft Academic Search

    G. Michael; R. Kadmi

    2007-01-01

    Ligand exchange chromatography is reported as an effective technique for the separation of sulfur compounds from hydrocarbon molecules in a petroleum fraction. Palladium (II) chloride anhydrous, ferric chloride 6?hydrate, copper (II) sulfate 5?hydrate, silver nitrate, and tin (II) chloride 2?hydrate were studied for their effectiveness to separate sulfur compounds present in a Kuwaiti diesel fraction. Tin, silver, and palladium salts

  11. ATP-sulfurylase, sulfur-compounds, and plant stress tolerance

    PubMed Central

    Anjum, Naser A.; Gill, Ritu; Kaushik, Manjeri; Hasanuzzaman, Mirza; Pereira, Eduarda; Ahmad, Iqbal; Tuteja, Narendra; Gill, Sarvajeet S.

    2015-01-01

    Sulfur (S) stands fourth in the list of major plant nutrients after N, P, and K. Sulfate (SO42-), a form of soil-S taken up by plant roots is metabolically inert. As the first committed step of S-assimilation, ATP-sulfurylase (ATP-S) catalyzes SO42--activation and yields activated high-energy compound adenosine-5?-phosphosulfate that is reduced to sulfide (S2-) and incorporated into cysteine (Cys). In turn, Cys acts as a precursor or donor of reduced S for a range of S-compounds such as methionine (Met), glutathione (GSH), homo-GSH (h-GSH), and phytochelatins (PCs). Among S-compounds, GSH, h-GSH, and PCs are known for their involvement in plant tolerance to varied abiotic stresses, Cys is a major component of GSH, h-GSH, and PCs; whereas, several key stress-metabolites such as ethylene, are controlled by Met through its first metabolite S-adenosylmethionine. With the major aim of briefly highlighting S-compound-mediated role of ATP-S in plant stress tolerance, this paper: (a) overviews ATP-S structure/chemistry and occurrence, (b) appraises recent literature available on ATP-S roles and regulations, and underlying mechanisms in plant abiotic and biotic stress tolerance, (c) summarizes ATP-S-intrinsic regulation by major S-compounds, and (d) highlights major open-questions in the present context. Future research in the current direction can be devised based on the discussion outcomes. PMID:25904923

  12. Identification of elementary sulfur and sulfur compounds in lipid extracts by thin-layer chromatography

    Microsoft Academic Search

    Mary T. J. Murphy; Bartholomew Nagy; George Rouser; Gene Kritchevsky

    1965-01-01

    Elementary sulfur, long chain thiols and sulfides in lipid mixtures can be separated and identified by thin layer chromatography\\u000a (TLC), preparation of derivatives, development of typical flourescent colors with Rhodamine 6G under ultraviolet light, and\\u000a colors with other spray reagents. Silica gel mixed with magnesium silicate and the same adsorbent plus silver nitrate are\\u000a used for polar stationary phase and

  13. The functional role of reduced inorganic sulfur compounds in the metabolism of the microaerophilic bacterium Spirillum winogradskii

    Microsoft Academic Search

    D. A. Podkopaeva; M. Yu. Grabovich; G. A. Dubinina

    2005-01-01

    Oxidation of reduced sulfur compounds by the microaerophilic sulfur bacterium spirillum winogradskii was found to occur only concomitantly with consumption of an organic substrate and was not linked to their utilization as electron donors in energy metabolism. No enzymes of dissimilatory sulfur metabolism were found in the cells of the sulfur bacterium oxidizing thiosulfate to tetrathionate; oxidation of thiosulfate and

  14. Lunar sulfur

    NASA Technical Reports Server (NTRS)

    Kuck, David L.

    1991-01-01

    Ideas introduced by Vaniman, Pettit and Heiken in their 1988 Uses of Lunar Sulfur are expanded. Particular attention is given to uses of SO2 as a mineral-dressing fluid. Also introduced is the concept of using sulfide-based concrete as an alternative to the sulfur-based concretes proposed by Leonard and Johnson. Sulfur is abundant in high-Ti mare basalts, which range from 0.16 to 0.27 pct. by weight. Terrestrial basalts with 0.15 pct. S are rare. For oxygen recovery, sulfur must be driven off with other volatiles from ilmenite concentrates, before reduction. Troilite (FeS) may be oxidized to magnetite (Fe3O4) and SO2 gas, by burning concentrates in oxygen within a magnetic field, to further oxidize ilmenite before regrinding the magnetic reconcentration. SO2 is liquid at -20 C, the mean temperature underground on the Moon, at a minimum of 0.6 atm pressure. By using liquid SO2 as a mineral dressing fluid, all the techniques of terrestrial mineral separation become available for lunar ores and concentrates. Combination of sulfur and iron in an exothermic reaction, to form iron sulfides, may be used to cement grains of other minerals into an anhydrous iron-sulfide concrete. A sulfur-iron-aggregate mixture may be heated to the ignition temperature of iron with sulfur to make a concrete shape. The best iron, sulfur, and aggregate ratios need to be experimentally established. The iron and sulfur will be by-products of oxygen production from lunar minerals.

  15. Measurement of molecular stopping cross sections of vaporous sulfur compounds and calculation of the atomic stopping cross section of sulfur

    NASA Astrophysics Data System (ADS)

    Olson, H. G.; Powers, D.

    1981-02-01

    The molecular stopping cross sections of hydrogen sulfide, methyl sulfide, methyl disulfide, carbon disulfide, ethylene sulfide, proplene sulfide, trimethylene sulfide, thiophene, and sulfur hexafluoride have beem measured for 0.3-2.0 MeV He+ ions. It is shown that the bond order correlation for the third period element sulfur is qualitatively in agreement with its second row counterpart, oxygen, but that the stopping cross-section dependence on bond order is considerably less (?5% in sulfur compared to ?17% in oxygen). In the energy region where the stopping contribution of the valence electrons is largest, the atomic stopping cross sections of sulfur for double-bonded, ring-structured, and single-bonded compounds decrease in the order eDB(S)?eRING(S)?eSB(S), a trend consistent with that observed for oxygen and carbon. The experimental results suggest a minimum d-orbital involvement in SF6 and reveal a lower peak energy Epeak and width d when S exists in the compound than when C, O, or F are present.

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

    NASA Technical Reports Server (NTRS)

    White, W. F.

    1974-01-01

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

  17. Effect of sulfur and its compounds on the performance of graphite electrooxidation in molten carbonate

    NASA Astrophysics Data System (ADS)

    Liu, Jia; Ye, Ke; Du, Mengmeng; Yin, Jinling; Cao, Dianxue; Wang, Guiling

    2015-01-01

    Direct carbon fuel cells are promising power sources with their performance significantly depending on the electrooxidation activity of carbon fuel. The impurities in the carbon fuel may affect the anode reactions. Sulfur and some of its inorganic compounds (CaSO4, K2SO3, K2S, FeS2) were added in molten carbonate and their effect on graphite electrooxidation was investigated. Cyclic voltammograms of gold electrode with addition of these sulfur compounds showed CaSO4 was stable and other compounds were electrochemically oxidized to high valence state sulfur compounds at operating voltage range. Linear sweep voltammetry of graphite with addition of sulfur compounds exhibited enhanced current density compared to pure graphite electrooxidation. Chronoamperometry was carried out to examine steady-state test of graphite electrooxidation in presence of sulfur compounds and the results indicated the enhanced current densities were caused by improved Boudouard reaction for CaSO4 and sulfur electrooxidation for other compounds, respectively. These inorganic sulfur compounds had no impact on electrooxidation process of graphite.

  18. Measurements of sulfur compounds in CO 2 by diode laser atomic absorption spectrometry

    NASA Astrophysics Data System (ADS)

    Franzke, J.; Stancu, D. G.; Niemax, K.

    2003-07-01

    Two simple methods for the analysis of the total concentration of sulfur in CO 2 by diode laser atomic absorption spectrometry of excited, metastable sulfur atoms in a direct current discharge are presented. In the first method, the CO 2 sample gas is mixed with the plasma gas (Ar or He) while the second is based on reproducible measurements of the sulfur released from the walls in a helium discharge after being deposited as a result of operating the discharge in pure CO 2 sample gas. The detection limits obtained satisfy the requirements for the control of sulfur compounds in CO 2 used in the food and beverage industry.

  19. Combined removal of sulfur compounds and nitrate by autotrophic denitrication in bioaugmented activated sludge system

    Microsoft Academic Search

    I. Manconi; A. Carucci; P. N. L. Lens

    2007-01-01

    An autotrophic denitrification process using reduced sulfur compounds (thiosulfate and sulfide) as electron donor in an activated sludge system is proposed as an efficient and cost effective alternative to conventional heterotrophic denitrification for inorganic (or with low C\\/N ratio) wastewaters and for simultaneous removal of sulfide or thiosulfate and nitrate. A suspended culture of sulfur-utilizing denitrifying bacteria was fast and

  20. Respiratory oxidation of reduced sulfur compounds by intact cells of Thiobacillus tepidarius (type strain)

    Microsoft Academic Search

    Trello Beffa; Catherine Fischer; Michel Aragno

    1992-01-01

    Thiobacillus tepidarius (type strain) was grown in microaerophilic conditions, on tetrathionate, thiosulfate or crystalline So. The rates of tetrathionate, thiosulfate, elemental sulfur (So) and sulfite oxidation of the different cultures were measured respirometrically, using exponentially growing cells, with an oxygen electrode. Cells growing on the three different sulfur compounds retain thiosulfate-, tetrathionate, and So-oxidizing activities (SOA), but lack respiratory sulfite-oxidizing

  1. A STUDY TO IMPROVE EPA METHODS 15 AND 16 FOR REDUCED SULFUR COMPOUNDS

    EPA Science Inventory

    EPA source test methods for reduced sulfur compounds, Method 15 for Claus sulfur recovery plants and Method 16 for Kraft pulp mills have been evaluated, and information is provided for the user. Techniques and procedures for the gas chromatographic measurement of hydrogen sulfide...

  2. Transformations of sulfur compounds in marsh-flat sediments

    SciTech Connect

    Swider, K.T.; Mackin, J.E. (SUNY at Stony Brook, NY (USA))

    1989-09-01

    Measurements were made in mud-flat sediments from Flax Pond salt marsh to characterize the rates and mechanisms of sulfur cycling in an organic-rich coastal marine environment. Approximately 13 mmoles/m{sup 2} of reduced sulfur are generated annually in the mud flat and the dominant solid-phase product is pyrite. Ion activity products involving dissolved iron and sulfide species indicate approximate saturation with respect to metastable iron sulfide phases, showing that pyrite is not likely to be the first-formed Fe-bearing sulfide. Comparison of {Sigma}H{sub 2}S vs. SO{sup =}{sub 4} relationships in anoxic incubation experiments with those occurring in the undisturbed sediment permits evaluation of possible mechanisms involved in the transformation of metastable iron monosulfides to pyrite. Oxidants (e.g. MnO{sub 2}) that are introduced into the surface sediment, either by animal activity or physical events, are apparently necessary to cause major oxidation of FeS and {Sigma}H{sub 2}S to pyrite and sulfate. Solid-phase sulfur analyses and net {Sigma}H{sub 2}S accumulation in sediment pore waters are consistent with major sulfide oxidation, indicating that approximately 95% of the sulfide generated in the mud flat is reoxidized to sulfate and roughly half of this oxidation involves dissolved sulfide. The major factors limiting reduced sulfur burial are physical and biological disturbances and a low abundance of reactive solid-phase iron (2 wt%).

  3. BIOGENIC SULFUR COMPOUNDS IN COASTAL ATMOSPHERES OF NORTH CAROLINA

    EPA Science Inventory

    Atmospheric H2S, SO2, and particulate SO4(-2), Na(+), C1(-), NH4(-), and NO3(-) were measured in two experiments on the North Carolina coast to determine the levels of biogenic sulfur species at marsh and estuarine locations where dissimilatory bacterial sulfate reduction produce...

  4. Inorganic sulfur oxidizing system in green sulfur bacteria

    Microsoft Academic Search

    Hidehiro Sakurai; Takuro Ogawa; Michiko Shiga; Kazuhito Inoue

    2010-01-01

    Green sulfur bacteria use various reduced sulfur compounds such as sulfide, elemental sulfur, and thiosulfate as electron\\u000a donors for photoautotrophic growth. This article briefly summarizes what is known about the inorganic sulfur oxidizing systems\\u000a of these bacteria with emphasis on the biochemical aspects. Enzymes that oxidize sulfide in green sulfur bacteria are membrane-bound\\u000a sulfide-quinone oxidoreductase, periplasmic (sometimes membrane-bound) flavocytochrome c

  5. Determination of sulfur compounds in hydrotreated transformer base oil by potentiometric titration.

    PubMed

    Chao, Qiu; Sheng, Han; Cheng, Xingguo; Ren, Tianhui

    2005-06-01

    A method was developed to analyze the distribution of sulfur compounds in model sulfur compounds by potentiometric titration, and applied to analyze hydrotreated transformer base oil. Model thioethers were oxidized to corresponding sulfoxides by tetrabutylammonium periodate and sodium metaperiodate, respectively, and the sulfoxides were titrated by perchloric acid titrant in acetic anhydride. The contents of aliphatic thioethers and total thioethers were then determined from that of sulfoxides in solution. The method was applied to determine the organic sulfur compounds in hydrotreated transformer base oil. PMID:15984215

  6. Metal phosphate reduction in the presence of gaseous sulfur compounds

    SciTech Connect

    Kriklivyi, D.I.; Klimovich, M.A.; Petrovskaya, N.A.

    1992-05-20

    The phosphorus used for combining with calcium oxide is usually obtained by means of thermally stable acidic or amphoteric oxide additives, i.e., almost only silicon dioxide, aluminum oxide, and aluminum silicate. The reduction of tricalcium phosphate and natural calcium phosphate ores by natural gas in the presence of such additives at an acidity coefficient (C{sub a}) of 1 may be brought to completion in 1-3 h. Increasing the C{sub a} of a charge to 1.5-3 facilitates solid-phase reduction of low-melting phosphate ores and raises the phosphorus vaporization rate. However solid-phase additives in the phosphate and their high consumption increase charge preparation cost and lower equipment efficiency. The purpose of this paper is to study a replacement of solid-phase fluxes by volatiles that can combine with basic oxides. This approach was examined theoretically as to the possibility of replacing solid-phase fluxes by hydrogen chloride and volatile sulfur compounds. The latter is often found in natural gases that could be used in the phosphorus industry without prior purification. 15 refs., 3 figs., 3 tabs.

  7. Volatile Sulfur Compounds as a Predictor for Esophagogastroduodenal Mucosal Injury

    PubMed Central

    Yoo, Seung Hee; Jung, Hyeon Sik; Sohn, Wee Sik; Kim, Bong Hwan; Ku, Bon Ho; Kim, Young Saeng; Park, Sang Woon

    2008-01-01

    Background/Aims Halitosis is a symptom that bothers patients more socially than medically and its pathogenic mechanisms are unclear and treatment armamenterium is limited. Clinicians generally ignored active interventions. Since halitosis is closely associated with volatile sulfur compounds (VSCs), we used a Halimeter and gas chromatography to measure VSCs in patients with Helicobacter-pylori (H. pylori)-associated gastric diseases. Methods We categorized 72 patients with H. pylori infection into two groups based on their endoscopic findings: a non-erosive mucosal group (NE, n=24) and an erosive mucosal group (E, n=48). Halitosis was objectively assessed by applying either a Halimeter to breath air or gas chromatography to gastric juice. Simultaneously, the expression of VSC-generating enzyme was measured with reverse-transcriptase PCR using mRNA isolated from biopsy tissues. Results The levels of VSCs in exhaled breaths or aspirated gastric juices differed significantly between the NE and E groups (p<0.00001), suggesting that VSCs might reflect eroded epithelial damage induced by H. pylori infection. The expressions of cystathionine ?-synthase (CBS) and cystathionine ?-lyase (CSE) were broadly consistent with the degree of mucosal injury. Conclusions Erosive changes in esophagogastroduodenal mucosa were strongly correlated with increased VSC levels, suggesting that halitosis might result from H. pylori-associated erosive lesions. PMID:20485620

  8. Evaluation of the performance of the HCTH exchange-correlation functional using a benchmark of sulfur compounds

    E-print Network

    Peterson, Kirk A.

    of sulfur compounds Julianna A. Altmann*a and Nicholas C. Handyb a Department of Chemistry, KingÏs College L a benchmark of sulfur-containing molecules. Optimised structural parameters, harmonic frequencies methodology and appropriate experimental results. It is shown that, for sulfur compounds that do not contain

  9. Lithium Polysulfidophosphates: A Family of Lithium-Conducting Sulfur-Rich Compounds for Lithium-Sulfur Batteries

    SciTech Connect

    Lin, Zhan [ORNL] [ORNL; Liu, Zengcai [ORNL] [ORNL; Fu, Wujun [ORNL] [ORNL; Dudney, Nancy J [ORNL] [ORNL; Liang, Chengdu [ORNL] [ORNL

    2013-01-01

    Given the great potential for improving the energy density of state-of-the-art lithium-ion batteries by a factor of 5, a breakthrough in lithium-sulfur (Li-S) batteries will have a dramatic impact in a broad scope of energy related fields. Conventional Li-S batteries that use liquid electrolytes are intrinsically short-lived with low energy efficiency. The challenges stem from the poor electronic and ionic conductivities of elemental sulfur and its discharge products. We report herein lithium polysulfidophosphates (LPSP), a family of sulfur-rich compounds, as the enabler of long-lasting and energy-efficient Li-S batteries. LPSP have ionic conductivities of 3.0 10-5 S cm-1 at 25 oC, which is 8 orders of magnitude higher than that of Li2S (~10-13 S cm-1). The high Li-ion conductivity of LPSP is the salient characteristic of these compounds that impart the excellent cycling performance to Li-S batteries. In addition, the batteries are configured in an all-solid state that promises the safe cycling of high-energy batteries with metallic lithium anodes.

  10. Approach for selective separation of thiophenic and sulfidic sulfur compounds from petroleum by methylation/demethylation.

    PubMed

    Wang, Meng; Zhao, Suoqi; Chung, Keng H; Xu, Chunming; Shi, Quan

    2015-01-20

    Detailed characterization of petroleum derived sulfur compounds has been challenging, due to the complex composition of the hydrocarbon matrix. A novel method was developed for selective separation of thiophenic and sulfidic compounds from petroleum. Sulfur compounds were methylated to sulfonium salts by AgBF4 and CH3I, then the polar salts were separated by precipitation from petroleum matrix. The thiophenic and sulfidic sulfonium salts were sequentially demethylated with 7-azaindole and 4-dimethylaminopyridine, obtaining original thiophenic and sulfidic compounds, respectively. The method was validated by model compounds, and applied to a diesel and a vacuum distillation petroleum fraction. Sulfur fractions were characterized by gas chromatography (GC) coupled with a sulfur chemiluminescence detector (SCD) and quadrupole mass spectrometry (MS), and high resolution Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS). The technique was effective to selectively obtain high-purity thiophenic and sulfidic compounds and showed rare discrimination among sulfur compounds with ranging molecular weights and degrees of unsaturation. The method would facilitate multifaceted detailed characterization of sulfur compounds in an organic complex matrix. PMID:25519193

  11. Process for forming sulfuric acid

    DOEpatents

    Lu, Wen-Tong P. (Upper St. Clair, PA)

    1981-01-01

    An improved electrode is disclosed for the anode in a sulfur cycle hydrogen generation process where sulfur dioxie is oxidized to form sulfuric acid at the anode. The active compound in the electrode is palladium, palladium oxide, an alloy of palladium, or a mixture thereof. The active compound may be deposited on a porous, stable, conductive substrate.

  12. Flash pyrolysis of coal, coal maceral, and coal-derived pyrite with on-line characterization of volatile sulfur compounds

    USGS Publications Warehouse

    Chou, I.-Ming; Lake, M.A.; Griffin, R.A.

    1988-01-01

    A Pyroprobe flash pyrolysis-gas chromatograph equipped with a flame photometric detector was used to study volatile sulfur compounds produced during the thermal decomposition of Illinois coal, coal macerals and coal-derived pyrite. Maximum evolution of volatile organic sulfur compounds from all coal samples occurred at a temperature of approximately 700??C. At this temperature, the evolution of thiophene, its alkyl isomers, and short-chain dialkyl sulfide compounds relative to the evolution of benzothiophene and dibenzothiophene compounds was greater from coal high in organic sulfur than from coal low in organic sulfur. The variation in the evolution of sulfur compounds observed for three separate coal macerals (exinite, vitrinite, and inertinite) was similar to that observed for whole coal samples. However, the variation trend for the macerals was much more pronounced. Decomposition of coal-derived pyrite with the evolution of elemental sulfur was detected at a temperature greater than 700??C. The results of this study indicated that the gas chromotographic profile of the volatile sulfur compounds produced during flash pyrolysis of coals and coal macerals varied as a function of the amount of organic sulfur that occurred in the samples. Characterization of these volatile sulfur compounds provides a better understanding of the behavior of sulfur in coal during the thermolysis process, which could be incorporated in the design for coal cleaning using flash pyrolysis techniques. ?? 1988.

  13. Bacterial Sulfur Globules: Occurrence, Structure and Metabolism

    Microsoft Academic Search

    Christiane Dahl; Alexander Prange

    Reduced sulfur compounds such as sulfide, polysulfides, thiosulfate, polythionates, and elemental sulfur are oxidized by a\\u000a large and diverse group of prokaryotes, including the phototrophic sulfur bacteria, the thiobacilli and other colorless sulfur\\u000a bacteria and some thermophilic Archaea. Typically, these sulfur compounds are oxidized to sulfate but in many cases globules of polymeric, water-insoluble sulfur\\u000a accumulate as a transient and

  14. Zeolites Remove Sulfur From Fuels

    NASA Technical Reports Server (NTRS)

    Voecks, Gerald E.; Sharma, Pramod K.

    1991-01-01

    Zeolites remove substantial amounts of sulfur compounds from diesel fuel under relatively mild conditions - atmospheric pressure below 300 degrees C. Extracts up to 60 percent of sulfur content of high-sulfur fuel. Applicable to petroleum refineries, natural-gas processors, electric powerplants, and chemical-processing plants. Method simpler and uses considerably lower pressure than current industrial method, hydro-desulfurization. Yields cleaner emissions from combustion of petroleum fuels, and protects catalysts from poisoning by sulfur.

  15. Air/water oxidative desulfurization of coal and sulfur-containing compounds

    NASA Astrophysics Data System (ADS)

    Warzinski, R. P.; Freidman, S.; LaCount, R. B.

    1981-02-01

    Air/water Oxydesulfurization has been demonstrated in autoclave experiments at the Pittsburgh Energy Technology Center for various coals representative of the major U. S. coal basins. The applicability at present of this treatment for producing an environmentally acceptable coal has been restricted by recently proposed SO2 emission standards for utility boilers. The product would, however, be attractive to the many smaller industrial coal users who cannot afford to operate and maintain flue gas desulfurization systems. It is also possible that the utility industry could realize a benefit by using chemically cleaned coal with partial flue gas scrubbing. The higher cost of the cleaned coal would be offset by the reduction in capital and operating costs resulting from decreased FGD requirements. The susceptibility of sulfur in coal to oxidative removal varies with the nature of the sulfur-containing species. The inorganic sulfur compounds, primarily pyrite, marcasite, and iron sulfate, are more amenable to treatment than the organically bound sulfur which exhibits varying degrees of resistance depending on its chemical environment. Air/water Oxydesulfurization consistently removes in excess of 90 percent of the pyritic sulfur; the extent and efficiency of organic sulfur removal however, depends on the type of coal and severity of treatment used. In general, the organic sulfur of the higher rank coals exhibits more resistance to treatment than that of the lower rank coals; however, the accompanying heating value is greater for the latter. Similar treatment of sulfur-containing model compounds further illustrates the relative susceptibilities of different chemical species to oxidation. Application of these data to the understanding of the complex chemistry involved in the treatment of coal is a preliminary step toward improving the efficiency of Oxydesulfurization.

  16. Effects of inhibitors and NaCl on the oxidation of reduced inorganic sulfur compounds by a marine acidophilic, sulfur-oxidizing bacterium, Acidithiobacillus thiooxidans strain SH

    Microsoft Academic Search

    Kazuo Kamimura; Emi Higashino; Tadayoshi Kanao; Tsuyoshi Sugio

    2005-01-01

    The effect of NaCl and the pathways of the oxidation of reduced inorganic sulfur compounds were studied using resting cells and cell-free extracts of Acidithiobacillus thiooxidans strain SH. This isolate specifically requires NaCl for growth. The oxidation of sulfur and sulfite by resting cells was strongly inhibited by 2-heptyl-4-hydroxyquinoline- N-oxide. Carbonylcyanide m-chlorophenyl-hydrazone and monensin were also relatively strong inhibitors. Thiosulfate-oxidizing

  17. Differential Protein Expression during Growth of Acidithiobacillus ferrooxidans on Ferrous Iron, Sulfur Compounds, or Metal Sulfides

    PubMed Central

    Ramírez, Pablo; Guiliani, Nicolas; Valenzuela, Lissette; Beard, Simon; Jerez, Carlos A.

    2004-01-01

    A set of proteins that changed their levels of synthesis during growth of Acidithiobacillus ferrooxidans ATCC 19859 on metal sulfides, thiosulfate, elemental sulfur, and ferrous iron was characterized by using two-dimensional polyacrylamide gel electrophoresis. N-terminal amino acid sequencing and mass spectrometry analysis of these proteins allowed their identification and the localization of the corresponding genes in the available genomic sequence of A. ferrooxidans ATCC 23270. The genomic context around several of these genes suggests their involvement in the energetic metabolism of A. ferrooxidans. Two groups of proteins could be distinguished. The first consisted of proteins highly upregulated by growth on sulfur compounds (and downregulated by growth on ferrous iron): a 44-kDa outer membrane protein, an exported 21-kDa putative thiosulfate sulfur transferase protein, a 33-kDa putative thiosulfate/sulfate binding protein, a 45-kDa putative capsule polysaccharide export protein, and a putative 16-kDa protein of unknown function. The second group of proteins comprised those downregulated by growth on sulfur (and upregulated by growth on ferrous iron): rusticyanin, a cytochrome c552, a putative phosphate binding protein (PstS), the small and large subunits of ribulose biphosphate carboxylase, and a 30-kDa putative CbbQ protein, among others. The results suggest in general a separation of the iron and sulfur utilization pathways. Rusticyanin, in addition to being highly expressed on ferrous iron, was also newly synthesized, as determined by metabolic labeling, although at lower levels, during growth on sulfur compounds and iron-free metal sulfides. During growth on metal sulfides containing iron, such as pyrite and chalcopyrite, both proteins upregulated on ferrous iron and those upregulated on sulfur compounds were synthesized, indicating that the two energy-generating pathways are induced simultaneously depending on the kind and concentration of oxidizable substrates available. PMID:15294777

  18. Stoichiometric modeling of oxidation of reduced inorganic sulfur compounds (Riscs) in Acidithiobacillus thiooxidans.

    PubMed

    Bobadilla Fazzini, Roberto A; Cortés, Maria Paz; Padilla, Leandro; Maturana, Daniel; Budinich, Marko; Maass, Alejandro; Parada, Pilar

    2013-08-01

    The prokaryotic oxidation of reduced inorganic sulfur compounds (RISCs) is a topic of utmost importance from a biogeochemical and industrial perspective. Despite sulfur oxidizing bacterial activity is largely known, no quantitative approaches to biological RISCs oxidation have been made, gathering all the complex abiotic and enzymatic stoichiometry involved. Even though in the case of neutrophilic bacteria such as Paracoccus and Beggiatoa species the RISCs oxidation systems are well described, there is a lack of knowledge for acidophilic microorganisms. Here, we present the first experimentally validated stoichiometric model able to assess RISCs oxidation quantitatively in Acidithiobacillus thiooxidans (strain DSM 17318), the archetype of the sulfur oxidizing acidophilic chemolithoautotrophs. This model was built based on literature and genomic analysis, considering a widespread mix of formerly proposed RISCs oxidation models combined and evaluated experimentally. Thiosulfate partial oxidation by the Sox system (SoxABXYZ) was placed as central step of sulfur oxidation model, along with abiotic reactions. This model was coupled with a detailed stoichiometry of biomass production, providing accurate bacterial growth predictions. In silico deletion/inactivation highlights the role of sulfur dioxygenase as the main catalyzer and a moderate function of tetrathionate hydrolase in elemental sulfur catabolism, demonstrating that this model constitutes an advanced instrument for the optimization of At. thiooxidans biomass production with potential use in biohydrometallurgical and environmental applications. PMID:23436458

  19. Sulfur/lithium-insertion compound composite cathodes for Li-S batteries

    NASA Astrophysics Data System (ADS)

    Su, Yu-Sheng; Manthiram, Arumugam

    2014-12-01

    A part of carbon additives in sulfur cathodes is replaced by lithium-insertion compounds as they can contribute extra capacity and increase the overall energy density. Accordingly, VO2(B) and TiS2 were incorporated into sulfur cathodes as they can work within the same voltage window as that of sulfur. However, VO2(B) was found to be incompatible with the glyme-based electrolytes that are usually used in Li-S cells, but TiS2 performs well while coupled with sulfur. The S/C/TiS2 composite cathode delivers 252 mAh g-1 more than that of pristine sulfur cathode (1334 mAh g-1 vs. 1082 mAh g-1). The increased capacity is not only due to the contribution by TiS2 itself but also due to a better active-material dispersion and utilization. Serving as active reaction sites during cycling, TiS2 suppresses agglomeration of sulfur and facilitates better ionic/electronic transport within the cathode structure. This composite cathode design provides another direction for Li-S batteries to improve the overall energy density.

  20. Low Temperature Sorbents for removal of Sulfur Compounds from fluid feed Streams

    SciTech Connect

    Siriwardane, Ranjan

    1999-09-30

    A sorbent material is provided comprising a material reactive with sulfur, a binder unreactive with sulfur and an inert material, wherein the sorbent absorbs the sulfur at temperatures between 30 and 200 C. Sulfur absorption capacity as high as 22 weight percent has been observed with these materials.

  1. Low Temperature Sorbents for Removal of Sulfur Compounds from Fluid Feed Streams

    DOEpatents

    Siriwardane, Ranjani

    2004-06-01

    A sorbent material is provided comprising a material reactive with sulfur, a binder unreactive with sulfur and an inert material, wherein the sorbent absorbs the sulfur at temperatures between 30 and 200 C. Sulfur absorption capacity as high as 22 weight percent has been observed with these materials.

  2. Uptake of Small Organic Compounds by Sulfuric Acid Aerosols: Dissolution and Reaction

    NASA Technical Reports Server (NTRS)

    Iraci, L. T.; Michelsen, R. R.; Ashbourn, S. F. M.; Staton, S. J. R.

    2003-01-01

    To assess the role of oxygenated volatile organic compounds in the upper troposphere and lower stratosphere, the interactions of a series of small organic compounds with low-temperature aqueous sulfuric acid will be evaluated. The total amount of organic material which may be taken up from the gas phase by dissolution, surface layer formation, and reaction during the particle lifetime will be quantified. Our current results for acetaldehyde uptake on 40 - 80 wt% sulfuric acid solutions will be compared to those of methanol, formaldehyde, and acetone to investigate the relationships between chemical functionality and heterogeneous activity. Where possible, equilibrium uptake will be ascribed to component pathways (hydration, protonation, etc.) to facilitate evaluation of other species not yet studied in low temperature aqueous sulfuric acid.

  3. Stimulation of proinflammatory cytokines by volatile sulfur compounds in endodontically treated teeth

    PubMed Central

    Lechner, Johann; von Baehr, Volker

    2015-01-01

    Persistent microorganisms in endodontically treated teeth produce volatile sulfur compounds (VSC) such as methyl mercaptan, hydrogen sulfide, and thioether. In this retrospective study, we evaluated the ex vivo immune response of peripheral blood mononuclear cells to sulfur compounds in 354 patients with systemic diseases. These systemic findings are correlated with semiquantitative values of a VSC indicator applied directly on endodontically treated teeth. Data elucidate the role of VSC in patients with immunologic diseases and the role of a semiquantitative chairside test, like the VSC indicator presented here, in correlation to IFNg and IL-10 sensitization in peripheral blood mononuclear cells. The association between ex vivo-stimulated cytokines and endodontically derived sulfur components is supported by the fact that the number of interferon gamma- and/or interleukin-10-positive sensitized patients declined significantly 3–8 months after extraction of the corresponding teeth.

  4. Gas chromatography combined with mass spectrometry for the identification of organic sulfur compounds in shellfish and fish

    SciTech Connect

    Ogata, M.; Miyake, Y.

    1980-11-01

    The authors determined that the organic sulfur compounds usually contained in crude oil can be used as a marker of oil pollution in shellfish and fish. Short-necked clams and eels were maintained in a controlled laboratory environment in water with suspension of crude oil. Mass spectra and mass chromatograms of short-necked clam extract showed the presence of organic sulfur compounds. Capillary column gas chromatography-mass chromatograms of crude oil and extract from the soft body of a short-necked clam showed the presence of organic sulfur compounds. Besides sulfur components, various other compounds were contained in crude oil and short-necked clam. Mass chromatograms of crude oil and the extract from eel flesh showed the presence of alkyl benzothiophene, dibenzothiophene, naphthalene, and alkyl naphthalene. Data indicated that the organic sulfur compounds and polyaromatic compounds could serve as markers of oil pollution in shellfish and fish.

  5. Sulfur compounds in therapy: Radiation-protective agents, amphetamines, and mucopolysaccharide sulfation

    SciTech Connect

    Foye, W.O. (Massachusetts College of Pharmacy and Allied Health Sciences, Boston (United States))

    1992-09-01

    Sulfur-containing compounds have been used in the search for whole-body radiation-protective compounds, in the design of amphetamine derivatives that retain appetite-suppressive effects but lack most behavioral effects characteristic of amphetamines, and in the search for the cause of kidney stone formation in recurrently stoneforming patients. Organic synthetic procedures were used to prepare radiation-protective compounds having a variety of sulfur-containing functional groups, and to prepare amphetamine derivatives having electron-attracting sulfur functions. In the case of the kidney stone causation research, isolation of urinary mucopolysaccharides (MPS) from recurrently stoneforming patients was carried out and the extent of sulfation of the MPS was determined by electrophoresis. Whole-body radiation-protective agents with a high degree of protection against lethal doses of gamma-radiation in mice were found in a series of quinolinium and pyridinium bis(methylthio) and methylthio amino derivatives. Mechanism studies showed that the copper complexes of these agents mimicked the beneficial action of superoxide dismutase. Electron-attracting sulfur-containing functions on amphetamine nitrogen, as well as 4'-amino nitrogen provided amphetamine derivatives with good appetite-suppressant effects and few or no adverse behavioral effects. Higher than normal levels of sulfation of the urinary MPS of stone formers suggested a cause for recurrent kidney stone formation. A sulfation inhibitor was found to prevent recurrence of stone formation and inhibit growth of existing stones. The inclusion of various sulfur-containing functions in organic molecules yielded compounds having whole-body radiation protection from lethal doses of gamma-radiation in animals. The presence of electron-attracting sulfur functions in amphetamine gave derivatives that retained appetite-suppressant effects and eliminated most adverse behavioral effects.

  6. Sulfuric acid-sulfur heat storage cycle

    DOEpatents

    Norman, John H. (LaJolla, CA)

    1983-12-20

    A method of storing heat is provided utilizing a chemical cycle which interconverts sulfuric acid and sulfur. The method can be used to levelize the energy obtained from intermittent heat sources, such as solar collectors. Dilute sulfuric acid is concentrated by evaporation of water, and the concentrated sulfuric acid is boiled and decomposed using intense heat from the heat source, forming sulfur dioxide and oxygen. The sulfur dioxide is reacted with water in a disproportionation reaction yielding dilute sulfuric acid, which is recycled, and elemental sulfur. The sulfur has substantial potential chemical energy and represents the storage of a significant portion of the energy obtained from the heat source. The sulfur is burned whenever required to release the stored energy. A particularly advantageous use of the heat storage method is in conjunction with a solar-powered facility which uses the Bunsen reaction in a water-splitting process. The energy storage method is used to levelize the availability of solar energy while some of the sulfur dioxide produced in the heat storage reactions is converted to sulfuric acid in the Bunsen reaction.

  7. Sulfur 1s near-edge x-ray absorption fine structure (NEXAFS) of thiol and thioether compounds

    SciTech Connect

    Beyhan, Shirin; Urquhart, Stephen G. [Department of Chemistry, University of Saskatchewan, Saskatoon, Saskatchewan S7N 5C9 (Canada); Hu Yongfeng [Canadian Light Source, University of Saskatchewan, Saskatoon, Saskatchewan S7N 5C6 (Canada)

    2011-06-28

    The speciation and quantification of sulfur species based on sulfur K-edge x-ray absorption spectroscopy is of wide interest, particularly for biological and petroleum science. These tasks require a firm understanding of the sulfur 1s near-edge x-ray absorption fine structure (NEXAFS) spectra of relevant species. To this end, we have examined the gas phase sulfur 1s NEXAFS spectra of a group of simple thiol and thioether compounds. These high-resolution gas phase spectra are free of solid-state broadening, charging, and saturation effects common in the NEXAFS spectra of solids. These experimental data have been further analyzed with the aid of improved virtual orbital Hartree-Fock ab initio calculations. The experimental sulfur 1s NEXAFS spectra show fine features predicted by calculation, and the combination of experiment and calculation has been used to improve assignment of spectroscopic features relevant for the speciation and quantification of the sulfur compounds.

  8. Measurements of hydrocarbons and reduced sulfur compounds emitted from a wastewater treatment pond

    SciTech Connect

    Tran, G.; Geen, C.; Friel, D. [BOVAR Environmental, Toronto, Ontario (Canada)

    1996-12-31

    A flux chamber was deployed on the water surface to monitor the emissions of hydrocarbons and reduced sulfur compounds from a wastewater treatment pond at a refinery site. Air samples were collected in Tedlar bags and analyzed on-site by means of a gas chromatograph/flame ionization detector (GC/FID) for hydrocarbons and a gas chromatograph/flame photometric detector (GC/FPD) for reduced sulfur compounds. The standard deviations of the duplicate samples for hydrocarbons and for reduced sulfur compounds were better than 4% and 11%, respectively. The pond was monitored during the daytime and nighttime, under two different weather conditions where the daytime temperatures were about 22{degrees}C and 14{degrees}C. The results showed that the difference between day and night emissions of hydrocarbons and reduced sulfur compounds were greater during the warm weather compared to those during cool weather. Air samples were also collected with charcoal adsorbent tubes and analyzed by means of a gas chromatograph/mass selective detector (GC/MSD) at the BOVAR Environmental (BE) laboratory to confirm the GC/FID hydrocarbon analyses. There was excellent agreement between hydrocarbons identified by GC/FID and GC/MSD. 10 refs., 3 figs.

  9. The loss patterns of reduced sulfur compounds in contact with different tubing materials

    Microsoft Academic Search

    Ki-Hyun Kim; Ji-Won Ahn; Ye-Jin Choi; Hang T. Nguyen

    2006-01-01

    To collect or transfer samples of airborne pollutants, tubings made of various materials are used. To analyze the reactive loss patterns of reduced sulfur compounds (RSC) in the use of tubing fittings, a series of laboratory experiments were conducted so that the concentration changes were induced by the physical contact between gas samples and tubing walls. For the purpose of

  10. INFLUENCE OF DIETARY METHIONINE SOURCE ON VOLATILE SULFUR COMPOUNDS IN BROILER EXCRETA

    Technology Transfer Automated Retrieval System (TEKTRAN)

    To evaluate the impact of methionine source on volatile sulfur compounds in broiler excreta a trial was conducted using straight run broiler chicks raised in battery cages. Chicks were randomly distributed into 3 replications of 5 treatment groups with 16 birds per pen. The treatment groups were d...

  11. Influence of anxiety on the production of oral volatile sulfur compounds

    Microsoft Academic Search

    Caroline Morini Calil; Fernanda Klein Marcondes

    2006-01-01

    Since many patients complain about halitosis without there being any clinical evidence of its cause, psychological symptoms have been pointed out as halitosis-inducing factors. The aim of this study was to evaluate the influence of anxiety on the production of volatile sulfur compounds (VSC). Seventeen undergraduate men in good oral and general health participated in this study, after approval by

  12. Volatile Organic Sulfur Compounds of Environmental Interest: Dimethyl Sulfide and Methanethiol

    ERIC Educational Resources Information Center

    Chasteen, Thomas G.; Bentley, Ronald

    2004-01-01

    Volatile organic sulfur compounds (VOSCs) have been assigned environmental roles in global warming, acid precipitation, and cloud formation where two important members dimethyl sulfide (CH3)2 S, DMS, and methanethiol, CH3SH, MT, of VOSC group are involved.

  13. Sulfur cycling in forests

    Microsoft Academic Search

    D. W. Johnson

    1984-01-01

    Sulfur is essential for the production of certain amino acids in plants. As amino acid sulfur is the major form of sulfur in trees, there is a strong relationship between organic S and organic N in tree tissue. Sulfur deficiencies occur in parts of southeastern Australia and northwestern North America, remote from pollutant inputs. Since bilogical S requirements of forests

  14. Low temperature removal of inorganic sulfur compounds from mining process waters.

    PubMed

    Liljeqvist, Maria; Sundkvist, Jan-Eric; Saleh, Amang; Dopson, Mark

    2011-06-01

    Process water and effluents from mining operations treating sulfide rich ores often contain considerable concentrations of metastable inorganic sulfur compounds such as thiosulfate and tetrathionate. These species may cause environmental problems if released to downstream recipients due to oxidation to sulfuric acid catalyzed by acidophilic microorganisms. Molecular phylogenic analysis of the tailings pond and recipient streams identified psychrotolerant and mesophilic inorganic sulfur compound oxidizing microorganisms. This suggested year round thiosalt oxidation occurs. Mining process waters may also contain inhibiting substances such as thiocyanate from cyanidation plants. However, toxicity experiments suggested their expected concentrations would not inhibit thiosalt oxidation by Acidithiobacillus ferrivorans SS3. A mixed culture from a permanently cold (4-6 °C) low pH environment was tested for thiosalt removal in a reactor design including a biogenerator and a main reactor containing a biofilm carrier. The biogenerator and main reactors were successively reduced in temperature to 5-6 °C when 43.8% of the chemical oxidation demand was removed. However, it was found that the oxidation of thiosulfate was not fully completed to sulfate since low residual concentrations of tetrathionate and trithionate were found in the discharge. This study has demonstrated the potential of using biotechnological solutions to remove inorganic sulfur compounds at 6°C and thus, reduce the impact of mining on the environment. PMID:21280027

  15. Sulfuric Acid in the Venus Clouds

    NASA Technical Reports Server (NTRS)

    Sill, G. T.

    1972-01-01

    The visible and ultraviolet transmission features of a thin layer of elemental bromine and hydrobromic acid dissolved in sulfuric acid somewhat resemble the Venus spectrum, up to 14 microns. The chemical process postulated for forming sulfuric acid involves the oxidation of sulfur and its compounds to sulfuric acid through the agency of elemental bromine, produced by the photolytic decomposition of hydrogen bromide.

  16. Quantification of volatile sulfur compounds in complex gaseous matrices by solid-phase microextraction

    Microsoft Academic Search

    Annika T Nielsen; Susanne Jonsson

    2002-01-01

    Procedures were assessed for quantifying nine volatile sulfur compounds found in complex gaseous samples collected at a biogas-production plant and a sewage treatment plant. The target compounds were extracted by solid-phase microextraction (using the 75-?m Carboxen–polydimethylsiloxane fiber coating) at 22°C for 20 min, and analyzed by GC–MS. Detection limits ranged between 1 pptv (v\\/v) for carbon disulfide and 470 pptv

  17. Sulfur and Hydrogen Isotope Anomalies in Organic Compounds from the Murchison Meteorite

    NASA Technical Reports Server (NTRS)

    Cooper, G. W.; Thiemens, M. H.; Jackson, T.; Chang, Sherwood

    1996-01-01

    Isotopic measurements have been made on organic sulfur and phosphorus compounds recently discovered in the Murchison meteorite. Carbon, hydrogen and sulfur measurements were performed on individual members of the organic sulfur compounds, alkyl sulfonates; and carbon and hydrogen measurements were made on bulk alkyl phosphonates. Cooper and Chang reported the first carbon isotopic measurements of Murchison organic sulfonates, providing insight into the potential synthetic mechanisms of these and, possibly, other organic species. Hydrogen isotopic measurements of the sulforiates now reveal deuterium excesses ranging from +660 to +2730 %. The deuterium enrichments indicate formation of the hydrocarbon portion of these compounds in a low temperature astrophysical environment consistent with that of dense molecular clouds. Measurements of the sulfur isotopes provide further constraints on the origin and mechanism of formation of these organic molecules. Recently, there has been growing documentation of sulfur isotopic anomalies in meteoritic material. Thiemens and Jackson have shown that some bulk ureilites possess excess S-33 and Thiemens et al. have reported excess S-33 in an oldhamite separate from the Norton County meteorite. Rees and Thode reported a large S-33 excess in an Allende acid residue, however, attempts to verify this measurements have been unsuccessful, possibly due to the heterogeneous nature of the carrier phase. With the recognition that sulfur isotopes may reflect chemistry in the protosolar nebula or the precursor molecular cloud, identification of potential carriers is of considerable interest. In the present study, the stable isotopes of sulfur were measured in methane sulfonic acid extracted from the Murchison meteorite. The isotopic composition was found to be: (delta)S-33 = 2.48 %, (delta)S-34 = 2.49 % and (delta)S-36 = 6.76 %. Based upon analysis of more than 60 meteoritic and numerous terrestrial samples, the mass fractionation lines are defined by Delta-33 = (delta)S-33 -0.50(delta)S-34 and Delta-36 = (delta)s-36 - 1.97 (delta)S-34. From these relationships Delta-33 = 1.24 % and Delta-36 = 0.89 % are observed. These anomalies, particularly the Delta-33, lie well outside the range of analytical uncertainty. They are the largest observed in any meteoritic component and the first found in an organosulfur compound. As discussed by Thiemens and Jackson, due to it's position on the periodic chart, sulfur undergoes chemically induced mass independent isotopic fractionations as does oxygen. Experiments by Mauersberger et. al. show that in such processes, the magnitude of fractionation for the different isotopically substituted species varies with mass and angular momentum; thus, anomalies are expected for both S-33 and S-36, but not necessarily of the same magnitude. Laboratory experiments have also confirmed that chemically produced, mass independent fractionations are mediated by molecular symmetry factors. A chemical source of fractionation requires that the sulfur isotopic anomaly was established in the gas phase, probably in reactions involving symmetric CS2. The discovery of an anomalous sulfur isotopic composition in a specific molecule containing excess deuterium is an important advance in the understanding of the cosmochemistry of sulfur. This evidence suggests that methanesulfonic acid was synthesized by interstellar processes. Further measurements and details of possible synthesis and fractionation mechanisms will be presented.

  18. Exploring the Arabidopsis sulfur metabolome.

    PubMed

    Gläser, Katharina; Kanawati, Basem; Kubo, Tobias; Schmitt-Kopplin, Philippe; Grill, Erwin

    2014-01-01

    Sulfur plays a crucial role in protein structure and function, redox status and plant biotic stress responses. However, our understanding of sulfur metabolism is limited to identified pathways. In this study, we used a high-resolution Fourier transform mass spectrometric approach in combination with stable isotope labeling to describe the sulfur metabolome of Arabidopsis thaliana. Databases contain roughly 300 sulfur compounds assigned to Arabidopsis. In comparative analyses, we showed that the overlap of the expected sulfur metabolome and the mass spectrometric data was surprisingly low, and we were able to assign only 37 of the 300 predicted compounds. By contrast, we identified approximately 140 sulfur metabolites that have not been assigned to the databases to date. We used our method to characterize the ?-glutamyl transferase mutant ggt4-1, which is involved in the vacuolar breakdown of glutathione conjugates in detoxification reactions. Although xenobiotic substrates are well known, only a few endogenous substrates have been described. Among the specifically altered sulfur-containing masses in the ggt4-1 mutant, we characterized one endogenous glutathione conjugate and a number of further candidates for endogenous substrates. The small percentage of predicted compounds and the high proportion of unassigned sulfur compounds identified in this study emphasize the need to re-evaluate our understanding of the sulfur metabolome. PMID:24147819

  19. Intermediary sulfur compounds in pyrite oxidation: implications for bioleaching and biodepyritization of coal

    Microsoft Academic Search

    A. Schippers; T. Rohwerder; W. Sand

    1999-01-01

    Accumulation of elemental sulfur during pyrite oxidation lowers the efficiency of coal desulfurization and bioleaching. In\\u000a the case of pyrite bioleaching by Leptospirillum ferrooxidans, an iron(II)-ion-oxidizing organism without sulfur-oxidizing capacity, from the pyritic sulfur moiety about 10% elemental\\u000a sulfur, 2% pentathionate, and 1% tetrathionate accumulated by a recently described cyclic pyrite oxidation mechanism. In the\\u000a case of pure cultures of

  20. ATMOSPHERIC CHEMISTRY OF SELECTED SULFUR-CONTAINING COMPOUNDS. OUTDOOR SMOG CHAMBER STUDY. PHASE 2

    EPA Science Inventory

    The photochemical behavior of mixtures of selected sulfur containing species, hydrocarbons, and nitrogen oxides was examined in outdoor smog chambers. Sulfur dioxide, H2S, CH3SH, COS, and thiophene are the sulfur species tested. A surrogate ambient hydrocarbon mixture comprised o...

  1. EVALUATION OF TECHNIQUES FOR MEASURING BIOGENIC AIRBORNE SULFUR COMPOUNDS, CEDAR ISLAND FIELD STUDY, 1977

    EPA Science Inventory

    Sulfur in both gaseous and particulate form has been measured near biogenic sources using new measurement techniques. The preconcentration of gaseous sulfur on gold-coated glass beads followed by desorption into a flame photometric detection for sulfur is shown to have a detectio...

  2. Magmatic sulfur compounds and sulfur diffusion in albite melt at 1 GPa and 1300-1500 8C

    Microsoft Academic Search

    K. TOBIAS WINTHER; E. BRUCE WATSON; GERALD M. KORENOWSKI

    The speciation and diffusion of sulfur in nominally dry albite melt at 1300-1500 8C has been investigated by analyzing glasses formed in piston-cylinder runs using electron microprobe, micro-Raman, infrared-, UV-, and visible-light-spectroscopy, and other tech- niques. The sulfate ion is very stable in the albite melt even at low and is the dominant f o2 species in all glasses. In

  3. Thermodynamics of Aqueous Organic Sulfur Compounds: A Key to the Organic Geochemistry of Hydrothermal Systems?

    NASA Technical Reports Server (NTRS)

    Schulte, Mitchell; Rogers, Karyn L.; DeVincenzi, Donald L. (Technical Monitor)

    2000-01-01

    Hydrothermal environments are locations of varied geochemistry due to the disequilibrium between vent fluids and seawater. The disequilibrium geochemistry has been hypothesized to include reactions to synthesize organic compounds. Observations of the organic geochemistry of hydrothermal vent sites has received little attention. Experimental simulations of these environments, however, indicate that organic compounds may have difficulty forming in a purely aqueous environment. On the other hand, thiols. thioesters and disulfides have been implicated as reaction intermediates between CO or CO2 in experiments of carbon reduction in hydrothermal environments as well as in a variety of biological processes and other abiotic reactions (Wachtershauser, 1990, OLEB 20, 173; Heinen and Lauwers, 1996, OLEB 26, 13 1, Huber and Wachtershauser, 1997, Science 276, 245; Russell et al., 1998, in Thermophiles: The keys to molecular evolution and the origin of life?). The reduction of CO2 to thiols, for example, is observed using the FeS-H2S/FeS2 couple to provide the reducing power (see Schoonen et al., 1999, OLEB 29, 5). In addition, the enzyme involved in final stage of methanogenesis, coenzyme-M, is itself a thiol. Thus, organic sulfur compounds may hold the key to the organic chemistry leading to the origin of life at high temperatures. Understanding the biochemical processes of microorganisms that can live to temperatures at least as high as 113 C (Blochl et al., 1996, Extremophiles 1, 14) requires knowledge of the properties of the chemical reactions involved. In order to assess the role of aqueous organic sulfur compounds in hydrothermal organic geochemistry, we have been attempting to determine their thermodynamic properties. We have culled the literature to obtain the properties of organic sulfur compounds. We are able to calculate a number of essential properties, such as free energies of formation, from solubility data available in the literature together with standard properties of organic sulfur gases. However, a number of the properties for aqueous organic sulfur compounds have not been experimentally determined. Furthermore, most of thermodynamic data that are available are for 25 C and 1 bar. In order to determine reaction properties to temperatures and pressures appropriate to the hydrothermal conditions in which thermophilic organisms actually live, we use equations of state developed by Helgeson and co-workers (Helgeson et al., 1981, AJS 281, 1249). A key piece of information needed to go up in temperature is the partial molal heat capacity, which is one of the properties for which experimental data are unavailable for nearly all organic sulfur compounds. We have used correlation methods to determine the partial molal heat capacities and volumes of many organic solutes. These estimates allow us to asses the role of organic sulfur compounds during the reduction of carbon in hydrothermal settings. We will present these data, along with examples of the thermodynamic properties of reactions involving aqueous organic sulfur compounds.

  4. Removal of sulfur compounds from petroleum re?nery wastewater through adsorption on modified activated carbon.

    PubMed

    Ben Hariz, Ichrak; Al Ayni, Foued; Monser, Lotfi

    2014-01-01

    The adsorption of sulfur compounds from petroleum refinery wastewater on a chemically modified activated carbon (MAC) was investigated. The modification technique (nitric acid, hydrogen peroxide and thermal modification) enhanced the removal capacity of carbon and therefore decreases cost-effective removal of sulfide from refinery wastewater. Adsorption equilibrium and kinetics data were determined for sulfur removal from real re?nery wastewater. The data were evaluated according to several adsorption isotherm and kinetics models. The Freundlich isotherm fitted well with the equilibrium data of sulfur on different adsorbents, whereas the kinetics data were best fitted by the pseudo-second-order model. Insights of sulfide removal mechanisms indicated that the sorption was controlled through the intraparticle diffusion mechanism with a significant contribution of film diffusion. The MAC adsorbent was found to have an effective removal capacity of approximately 2.5 times that of non-modified carbon. Using different MAC, sulfides were eliminated with a removal capacity of 52 mg g(-1). Therefore, MAC can be utilized as an effective and less expensive adsorbent for the reduction of sulfur in refinery wastewater. PMID:25353943

  5. Emission of volatile organic sulfur compounds (VOSCs) during aerobic decomposition of food wastes

    NASA Astrophysics Data System (ADS)

    Wu, Ting; Wang, Xinming; Li, Dejun; Yi, Zhigang

    2010-12-01

    Food wastes collected from typical urban residential communities were investigated for the emission of volatile organic sulfur compounds (VOSCs) during laboratory-controlled aerobic decomposition in an incubator for a period of 41 days. Emission of VOSCs from the food wastes totaled 409.9 mg kg -1 (dry weight), and dimethyl disulfide (DMDS), dimethyl sulfide (DMS), methyl 2-propenyl disulfide, carbonyl sulfide and methyl 1-propenyl sulfide were the five most abundant VOSCs, with shares of 75.5%, 13.5%, 4.8%, 2.2% and 1.3% in total 15 VOSCs released, respectively. The emission fluxes of major VOSCs were very low at the beginning (day 0). They peaked at days 2-4 and then decreased sharply until they leveled off after 10 days of incubation. For most VOSCs, over 95% of their emission occurred in the first 10 days. The time series of VOSC emission fluxes, as well as their significant correlation with internal food waste temperature ( p < 0.05) during incubation, suggested that production of VOSC species was induced mainly by microbial activities during the aerobic decomposition instead of as inherited. Released VOSCs accounted for 5.3% of sulfur content in the food wastes, implying that during aerobic decomposition considerable portion of sulfur in food wastes would be released into the atmosphere as VOSCs, primarily as DMDS, which is very short-lived in the atmosphere and thus usually less considered in the sources and sinks of reduced sulfur gases.

  6. Enhanced Elemental Mercury Removal from Coal-fired Flue Gas by Sulfur-chlorine Compounds

    SciTech Connect

    Chang, Shih-Ger; Yan, Nai-Qiang; Qu, Zan; Chi, Yao; Qiao, Shao-Hua; Dod, Ray; Chang, Shih-Ger; Miller, Charles

    2008-07-02

    Oxidation of Hg0 with any oxidant or converting it to a particle-bound form can facilitate its removal. Two sulfur-chlorine compounds, sulfur dichloride (SCl2) and sulfur monochloride (S2Cl2), were investigated as oxidants for Hg0 by gas phase reaction and by surface-involved reactions in the presence of flyash or activated carbon. The gas phase reaction rate constants between Hg0 and the sulfur/chlorine compounds were determined, and the effects of temperature and the main components in flue gases were studied. The gas phase reaction between Hg0 and SCl2 is shown to be more rapid than the gas phase reaction with chlorine, and the second order rate constant was 9.1(+-0.5) x 10-18 mL-molecules-1cdots-1 at 373oK. Nitric oxide (NO) inhibited the gas phase reaction of Hg0 with sulfur-chlorine compounds. The presence of flyash or powdered activated carbon in flue gas can substantially accelerate the reaction. The predicted Hg0 removal is about 90percent with 5 ppm SCl2 or S2Cl2 and 40 g/m3 of flyash in flue gas. The combination of activated carbon and sulfur-chlorine compounds is an effective alternative. We estimate that co-injection of 3-5 ppm of SCl2 (or S2Cl2) with 2-3 Lb/MMacf of untreated Darco-KB is comparable in efficiency to the injection of 2-3 Lb/MMacf Darco-Hg-LH. Extrapolation of kinetic results also indicates that 90percent of Hg0 can be removed if 3 Lb/MMacf of Darco-KB pretreated with 3percent of SCl2 or S2Cl2 is used. Unlike gas phase reactions, NO exhibited little effect on Hg0 reactions with SCl2 or S2Cl2 on flyash or activated carbon. Mercuric sulfide was identified as one of the principal products of the Hg0/SCl2 or Hg0/S2Cl2 reactions. Additionally, about 8percent of SCl2 or S2Cl2 in aqueous solutions is converted to sulfide ions, which would precipitate mercuric ion from FGD solution.

  7. Regulation of a Novel Acidithiobacillus caldus Gene Cluster Involved in Metabolism of Reduced Inorganic Sulfur Compounds

    Microsoft Academic Search

    Olena I. Rzhepishevska; Jorge Valdes; Liucija Marcinkeviciene; Camelia Algora Gallardo; Rolandas Meskys; Violaine Bonnefoy; David S. Holmes; Mark Dopson

    2007-01-01

    Acidithiobacillus caldus has been proposed to play a role in the oxidation of reduced inorganic sulfur compounds (RISCs) produced in industrial biomining of sulfidic minerals. Here, we describe the regu- lation of a new cluster containing the gene encoding tetrathionate hydrolase (tetH), a key enzyme in the RISC metabolism of this bacterium. The cluster contains five cotranscribed genes, ISac1, rsrR,

  8. Sulfuric acid poisoning

    MedlinePLUS

    Sulfuric acid is a very strong chemical that is corrosive. Corrosive means it can cause severe burns and ... or mucous membranes. This article discusses poisoning from sulfuric acid. This is for information only and not for ...

  9. Molecular Structure of sulfur

    NSDL National Science Digital Library

    2002-08-26

    The discoverer of sulfur remains anonymous because of lack of records. However, one can trace back to the discovery of R.W. Wood when he used ultra-violet rays to find a sulfur deposit near the crater of Aristarchus on the moon. Sulfur is also found in meteorites. In the United States, Sulfur can be found along the Gulf Coast in wells sunk along salt domes. It is brought to the surface using the Frasch Process in which heated water is forced into the wells and melts the surface. Sulfur may also be found in volcanos or hot springs. Other uses of Sulfur include making phosphatic fertilizers, matches, and medicine. The mineral is a good insulator and takes part in bleaching dried fruit. Sulfur is a minor constitute of body fluids, fats, and skeletal minerals. It can be said that Sulfur is essential to life.

  10. Microbiological fractionation of stable sulfur isotopes: A review and critique

    Microsoft Academic Search

    L. A. Chambers; P. A. Trudinger

    1979-01-01

    Microbiological transformations of sulfur compounds discriminate to various degrees between the stable sulfur isotopes S and S. Comparatively little is known on isotopic effects associated with sulfur?oxidizing organisms, and the interpretation of results is complicated since the sulfur pathways are poorly defined and compounds containing two or more sulfur atoms at different oxidation states may be involved. Dissimilatory reduction of

  11. Complete genome sequence of the sulfur compounds oxidizing chemolithoautotroph Sulfuricurvum kujiense type strain (YK-1T)

    SciTech Connect

    Han, Cliff [Los Alamos National Laboratory (LANL); Kotsyurbenko, Oleg [Technical University of Braunschweig; Chertkov, Olga [Los Alamos National Laboratory (LANL); Held, Brittany [Los Alamos National Laboratory (LANL); Lapidus, Alla L. [U.S. Department of Energy, Joint Genome Institute; Nolan, Matt [U.S. Department of Energy, Joint Genome Institute; Lucas, Susan [U.S. Department of Energy, Joint Genome Institute; Hammon, Nancy [U.S. Department of Energy, Joint Genome Institute; Deshpande, Shweta [U.S. Department of Energy, Joint Genome Institute; Cheng, Jan-Fang [U.S. Department of Energy, Joint Genome Institute; Tapia, Roxanne [Los Alamos National Laboratory (LANL); Goodwin, Lynne A. [Los Alamos National Laboratory (LANL); Pitluck, Sam [U.S. Department of Energy, Joint Genome Institute; Liolios, Konstantinos [U.S. Department of Energy, Joint Genome Institute; Pagani, Ioanna [U.S. Department of Energy, Joint Genome Institute; Ivanova, N [U.S. Department of Energy, Joint Genome Institute; Mavromatis, K [U.S. Department of Energy, Joint Genome Institute; Mikhailova, Natalia [U.S. Department of Energy, Joint Genome Institute; Pati, Amrita [U.S. Department of Energy, Joint Genome Institute; Chen, Amy [U.S. Department of Energy, Joint Genome Institute; Palaniappan, Krishna [U.S. Department of Energy, Joint Genome Institute; Land, Miriam L [ORNL; Hauser, Loren John [ORNL; Chang, Yun-Juan [ORNL; Jeffries, Cynthia [Oak Ridge National Laboratory (ORNL); Brambilla, Evelyne-Marie [DSMZ - German Collection of Microorganisms and Cell Cultures GmbH, Braunschweig, Germany; Rohde, Manfred [HZI - Helmholtz Centre for Infection Research, Braunschweig, Germany; Spring, Stefan [DSMZ - German Collection of Microorganisms and Cell Cultures GmbH, Braunschweig, Germany; Sikorski, Johannes [DSMZ - German Collection of Microorganisms and Cell Cultures GmbH, Braunschweig, Germany; Goker, Markus [DSMZ - German Collection of Microorganisms and Cell Cultures GmbH, Braunschweig, Germany; Woyke, Tanja [U.S. Department of Energy, Joint Genome Institute; Bristow, James [U.S. Department of Energy, Joint Genome Institute; Eisen, Jonathan [U.S. Department of Energy, Joint Genome Institute; Markowitz, Victor [U.S. Department of Energy, Joint Genome Institute; Hugenholtz, Philip [U.S. Department of Energy, Joint Genome Institute; Kyrpides, Nikos C [U.S. Department of Energy, Joint Genome Institute; Klenk, Hans-Peter [DSMZ - German Collection of Microorganisms and Cell Cultures GmbH, Braunschweig, Germany; Detter, J. Chris [U.S. Department of Energy, Joint Genome Institute

    2012-01-01

    Sulfuricurvum kujiense Kodama and Watanabe 2004 is the type species of the monotypic genus Sulfuricurvum, which belongs to the family Helicobacteriaceae in the class Epsilonproteobacteria. The species is of interest because it is frequently found in crude oil and oil sands where it utilizes various reduced sulfur compounds such as elemental sulfur, sulfide and thiosulfate as electron donors. Members of the species do not utilize sugars, organic acids and hydrocarbons as carbon and energy sources. This is the first completed genome sequence of a member of the genus Sulfuricurvum. The genome, which consists of a circular chromosome of 2,574,824 bp length and four plasmids of 118,585 bp, 71,513 bp, 51,014 bp, and 3,421 bp length, respectively, harboring a total of 2,879 protein-coding and 61 RNA genes and is a part of the Genomic Encyclopedia of Bacteria and Archaea project.

  12. PCDD/Fs' suppression by sulfur-amine/ammonium compounds.

    PubMed

    Fu, Jian-Ying; Li, Xiao-Dong; Chen, Tong; Lin, Xiao-Qing; Buekens, Alfons; Lu, Sheng-Yong; Yan, Jian-Hua; Cen, Ke-Fa

    2015-03-01

    Three distinct -S and -NH2 or NH4(+) containing compounds, including ammonium thiosulfate, aminosulfonic acid and thiourea, were studied as polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) inhibitors. All these three -S and -N containing compounds tested show strong suppression of PCDD/Fs formation, especially for thiourea which has not been studied before. With a (S+N)/Cl molar ratio of only 0.47, thiourea could inhibit 97.3% of PCDD/Fs and even 99.8% of I-TEQ. At an unusually high de novo test temperature (650 °C), the PCDD/Fs' formation was still very low but also the inhibition capacity of thiourea was weak, with an efficiency of 59% for PCDD/Fs when with a (S+N)/Cl molar ratio of 1.40. The results also revealed that the inhibition capability of the combined -S/-NH2 or -S/NH4(+) suppressant was strongly influenced by both the nature of the functional group of nitrogen and the value of the molar ratio (S+N)/Cl. The amine functional group -NH2 tends to be more efficient than ammonium NH4(+) and within a certain range a higher (S+N)/Cl value leads to a higher inhibition efficiency. Moreover, the emission of gases was continuously monitored: the Gasmet results revealed that SO2, HCN and NH3 were the most important decomposition products of thiourea. Thiourea is non-toxic, environment-friendly and can be sprayed into the post-combustion zone in form of powder or aqueous solution. The cost of thiourea at least can be partially compensated by its high inhibition efficiency. Therefore, the application of thiourea in a full-scale incinerator system is promising and encouraging. PMID:25481352

  13. Sulfuric acid on Europa and the radiolytic sulfur cycle

    NASA Technical Reports Server (NTRS)

    Carlson, R. W.; Johnson, R. E.; Anderson, M. S.

    1999-01-01

    A comparison of laboratory spectra with Galileo data indicates that hydrated sulfuric acid is present and is a major component of Europa's surface. In addition, this moon's visually dark surface material, which spatially correlates with the sulfuric acid concentration, is identified as radiolytically altered sulfur polymers. Radiolysis of the surface by magnetospheric plasma bombardment continuously cycles sulfur between three forms: sulfuric acid, sulfur dioxide, and sulfur polymers, with sulfuric acid being about 50 times as abundant as the other forms. Enhanced sulfuric acid concentrations are found in Europa's geologically young terrains, suggesting that low-temperature, liquid sulfuric acid may influence geological processes.

  14. Replacement of a Thiourea-S with an Amidine-NH Donor Group in a Platinum-Acridine Antitumor Compound Reduces the Metal's Reactivity with Cysteine Sulfur

    E-print Network

    Compound Reduces the Metal's Reactivity with Cysteine Sulfur Zhidong Ma, Lu Rao, and Ulrich Bierbach, 2009 The reactivity of two DNA-targeted platinum-acridine conjugates with cysteine sulfur was studied cisplatin (cis- [PtCl2(NH3)2]) with the intracellular sulfur-containing nucleo- phile glutathione (-L

  15. Molecular Structure of Sulfuric Acid

    NSDL National Science Digital Library

    2002-08-15

    H2SO4 was discovered by alchemists and made from heating a compound of iron sulfate. In 1740, sulfuric acid was produced for commercial sale. Sulfuric acid is a very strong acid which is used in car batteries. The acid disassociates in water to give two protons and sulfate. This acid can destroy flesh and cause blindness. It was discovered in the 19th century that adding sulfuric acid to soil produces phosphorus, which is beneficial to plants; hence, sulfuric acid is used as a fertilizer in the form of super phosphate and ammonium sulfate. Sulfuric acid is also used to refine petroleum and process metals, and is found in paints and car batteries.

  16. 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.

  17. Formation of Volatile Sulfur-Containing Compounds by Saccharomyces cerevisiae in Soymilk Supplemented with L-methionine

    Microsoft Academic Search

    Jasmine Mei Bei Quek; Yi-Xin Seow; Peter K. C. Ong; Shao-Quan Liu

    2011-01-01

    The formation of volatile sulfur-containing flavor compounds from L-methionine catabolism by Saccharomyces cerevisiae EC-1118 was investigated in soymilk supplemented with this sulfur-containing amino acid with a focus on methionol (3-methylthio-1-propanol). Methionol produced from L-methionine metabolism of yeast in soymilk was extracted by solid-phase microextraction (SPME) and analyzed by gas chromatography-mass spectrometry (GC-MS). The effects of time (0 – 72 h),

  18. Isotopically labeled sulfur compounds and synthetic selenium and tellurium analogues to study sulfur metabolism in marine bacteria

    PubMed Central

    Brock, Nelson L; Citron, Christian A; Zell, Claudia; Berger, Martine; Wagner-Döbler, Irene; Petersen, Jörn; Brinkhoff, Thorsten; Simon, Meinhard

    2013-01-01

    Summary Members of the marine Roseobacter clade can degrade dimethylsulfoniopropionate (DMSP) via competing pathways releasing either methanethiol (MeSH) or dimethyl sulfide (DMS). Deuterium-labeled [2H6]DMSP and the synthetic DMSP analogue dimethyltelluriopropionate (DMTeP) were used in feeding experiments with the Roseobacter clade members Phaeobacter gallaeciensis DSM 17395 and Ruegeria pomeroyi DSS-3, and their volatile metabolites were analyzed by closed-loop stripping and solid-phase microextraction coupled to GC–MS. Feeding experiments with [2H6]DMSP resulted in the incorporation of a deuterium label into MeSH and DMS. Knockout of relevant genes from the known DMSP demethylation pathway to MeSH showed in both species a residual production of [2H3]MeSH, suggesting that a second demethylation pathway is active. The role of DMSP degradation pathways for MeSH and DMS formation was further investigated by using the synthetic analogue DMTeP as a probe in feeding experiments with the wild-type strain and knockout mutants. Feeding of DMTeP to the R. pomeroyi knockout mutant resulted in a diminished, but not abolished production of demethylation pathway products. These results further corroborated the proposed second demethylation activity in R. pomeroyi. Isotopically labeled [2H3]methionine and 34SO4 2?, synthesized from elemental 34S8, were tested to identify alternative sulfur sources besides DMSP for the MeSH production in P. gallaeciensis. Methionine proved to be a viable sulfur source for the MeSH volatiles, whereas incorporation of labeling from sulfate was not observed. Moreover, the utilization of selenite and selenate salts by marine alphaproteobacteria for the production of methylated selenium volatiles was explored and resulted in the production of numerous methaneselenol-derived volatiles via reduction and methylation. The pathway of selenate/selenite reduction, however, proved to be strictly separated from sulfate reduction. PMID:23766810

  19. Determination of total sulfur content via sulfur-specific chemiluminescence detection

    SciTech Connect

    Kubala, S.W.; Campbell, D.N. [Fluid Data, Inc., Angleton, TX (United States); DiSanzo, F.P. [Paulsboro Research Lab., NJ (United States)

    1995-12-31

    A specially designed system, based upon sulfur-specific chemiluminescence detection (SSCD), was developed to permit the determination of total sulfur content in a variety of samples. This type of detection system possesses several advantages such as excellent linearity and selectivity, low minimum detectable levels, and an equimolar response to various sulfur compounds. This paper will focus on the design and application of a sulfur-specific chemiluminescence detection system for use in determining total sulfur content in gasoline.

  20. Direct night-time ejection of particle-phase reduced biogenic sulfur compounds from the ocean to the atmosphere.

    PubMed

    Gaston, Cassandra J; Furutani, Hiroshi; Guazzotti, Sergio A; Coffee, Keith R; Jung, Jinyoung; Uematsu, Mitsuo; Prather, Kimberly A

    2015-04-21

    The influence of oceanic biological activity on sea spray aerosol composition, clouds, and climate remains poorly understood. The emission of organic material and gaseous dimethyl sulfide (DMS) from the ocean represents well-documented biogenic processes that influence particle chemistry in marine environments. However, the direct emission of particle-phase biogenic sulfur from the ocean remains largely unexplored. Here we present measurements of ocean-derived particles containing reduced sulfur, detected as elemental sulfur ions (e.g., (32)S(+), (64)S2(+)), in seven different marine environments using real-time, single particle mass spectrometry; these particles have not been detected outside of the marine environment. These reduced sulfur compounds were associated with primary marine particle types and wind speeds typically between 5 and 10 m/s suggesting that these particles themselves are a primary emission. In studies with measurements of seawater properties, chlorophyll-a and atmospheric DMS concentrations were typically elevated in these same locations suggesting a biogenic source for these sulfur-containing particles. Interestingly, these sulfur-containing particles only appeared at night, likely due to rapid photochemical destruction during the daytime, and comprised up to ?67% of the aerosol number fraction, particularly in the supermicrometer size range. These sulfur-containing particles were detected along the California coast, across the Pacific Ocean, and in the southern Indian Ocean suggesting that these particles represent a globally significant biogenic contribution to the marine aerosol burden. PMID:25835033

  1. Lunar Sulfur Capture System

    NASA Technical Reports Server (NTRS)

    Berggren, Mark; Zubrin, Robert; Bostwick-White, Emily

    2013-01-01

    The Lunar Sulfur Capture System (LSCS) protects in situ resource utilization (ISRU) hardware from corrosion, and reduces contaminant levels in water condensed for electrolysis. The LSCS uses a lunar soil sorbent to trap over 98 percent of sulfur gases and about two-thirds of halide gases evolved during hydrogen reduction of lunar soils. LSCS soil sorbent is based on lunar minerals containing iron and calcium compounds that trap sulfur and halide gas contaminants in a fixed-bed reactor held at temperatures between 250 and 400 C, allowing moisture produced during reduction to pass through in vapor phase. Small amounts of Earth-based polishing sorbents consisting of zinc oxide and sodium aluminate are used to reduce contaminant concentrations to one ppm or less. The preferred LSCS configuration employs lunar soil beneficiation to boost concentrations of reactive sorbent minerals. Lunar soils contain sulfur in concentrations of about 0.1 percent, and halogen compounds including chlorine and fluorine in concentrations of about 0.01 percent. These contaminants are released as gases such as H2S, COS, CS2,HCl, and HF during thermal ISRU processing with hydrogen or other reducing gases. Removal of contaminant gases is required during ISRU processing to prevent hardware corrosion, electrolyzer damage, and catalyst poisoning. The use of Earth-supplied, single-use consumables to entirely remove contaminants at the levels existing in lunar soils would make many ISRU processes unattractive due to the large mass of consumables relative to the mass of oxygen produced. The LSCS concept of using a primary sorbent prepared from lunar soil was identified as a method by which the majority of contaminants could be removed from process gas streams, thereby substantially reducing the required mass of Earth-supplied consumables. The LSCS takes advantage of minerals containing iron and calcium compounds that are present in lunar soil to trap sulfur and halide gases in a fixedbed reactor downstream of an in-ISRU process such as hydrogen reduction. The lunar-soil-sorbent trap is held at a temperature significantly lower than the operating temperature of the hydrogen reduction or other ISRU process in order to maximize capture of contaminants, but is held at a high enough temperature to allow moisture to pass through without condensing. The lunar soil benefits from physical beneficiation to remove ultrafine particles (to reduce pressure drop through a fixed bed reactor) and to upgrade concentrations of iron and/or calcium compounds (to improve reactivity with gaseous contaminants).

  2. Groundwater contamination by volatile halogenated alkanes: abiotic formation of volatile sulfur compounds under anaerobic conditions

    SciTech Connect

    Schwarzenbach, R.P.; Giger, W.; Schaffner, C.; Wanner, O.

    1985-01-01

    The investigation of a groundwater contamination caused by a leaking wastewater tank of a chemical plant revealed that in groundwaters, under highly reducing conditions in the presence of hydrogen sulfide, certain volatile bromo- and chloroalkanes may undergo second-order nucleophilic substitution reactions yielding very persistent and hazardous volatile sulfur-containing compounds including dialkyl sulfides. Rate constants determined in the laboratory indicate that these nucleophilic substitution reactions may compete with hydrolysis, even at the low hydrogen sulfide concentrations typically encountered in the aquatic environment.

  3. Enzymology of carbon–sulfur bond formation

    Microsoft Academic Search

    Andrée Marquet

    2001-01-01

    Mobilization of the sulfur of cysteine as persulfide is the first step of sulfur transfer into thiamin, molydopterin, 4-thiouridine, biotin and lipoic acid, but then the pathways diverge completely. For the first three compounds, one or several proteinic persulfides are involved, ending in the nucleophilic attack of a sulfur, persulfide, sulfide or thiocarboxylate on a carbonyl equivalent. Several proteins have

  4. The global sulfur cycle

    NASA Technical Reports Server (NTRS)

    Sagan, D. (editor)

    1985-01-01

    The results of the planetary biology microbial ecology's 1984 Summer Research Program, which examined various aspects of the global sulfur cycle are summarized. Ways in which sulfur flows through the many living and chemical species that inhabit the surface of the Earth were investigated. Major topics studied include: (1) sulfur cycling and metabolism of phototropic and filamentous sulfur bacteria; (2) sulfur reduction in sediments of marine and evaporite environments; (3) recent cyanobacterial mats; (4) microanalysis of community metabolism in proximity to the photic zone in potential stromatolites; and (5) formation and activity of microbial biofilms on metal sulfides and other mineral surfaces. Relationships between the global sulfur cycle and the understanding of the early evolution of the Earth and biosphere and current processes that affect global habitability are stressed.

  5. Spectator Auger transitions of the 1s hole states in ionic sulfur compounds and molecular chlorine compounds

    Microsoft Academic Search

    Teikichi A. Sasaki; Yuji Baba; Kenji Yoshii; Hiroyuki Yamamoto

    1995-01-01

    The Auger transitions after resonant S1s ? 3p? (3p? indicates unoccupied states with 3p character) and C11s ? 3p? excitations were studied for sulfur compounds (MoS2, Li2SO4 and Na2S2O3) and chlorine compounds (Si(CH3)3Cl and SiCl4 solidified on Cu(100) surface) by photoemission spectroscopy using synchrotron radiation. In the photon energy of the resonant excitations, the KL2,3L2,3 spectator Auger line was found

  6. Genome-Wide Transcriptional Profiling of the Purple Sulfur Bacterium Allochromatium vinosum DSM 180T during Growth on Different Reduced Sulfur Compounds

    PubMed Central

    Weissgerber, Thomas; Dobler, Nadine; Polen, Tino; Latus, Jeanette; Stockdreher, Yvonne

    2013-01-01

    The purple sulfur bacterium Allochromatium vinosum DSM 180T is one of the best-studied sulfur-oxidizing anoxygenic phototrophic bacteria, and it has been developed into a model organism for laboratory-based studies of oxidative sulfur metabolism. Here, we took advantage of the organism's high metabolic versatility and performed whole-genome transcriptional profiling to investigate the response of A. vinosum cells upon exposure to sulfide, thiosulfate, elemental sulfur, or sulfite compared to photoorganoheterotrophic growth on malate. Differential expression of 1,178 genes was observed, corresponding to 30% of the A. vinosum genome. Relative transcription of 551 genes increased significantly during growth on one of the different sulfur sources, while the relative transcript abundance of 627 genes decreased. A significant number of genes that revealed strongly enhanced relative transcription levels have documented sulfur metabolism-related functions. Among these are the dsr genes, including dsrAB for dissimilatory sulfite reductase, and the sgp genes for the proteins of the sulfur globule envelope, thus confirming former results. In addition, we identified new genes encoding proteins with appropriate subcellular localization and properties to participate in oxidative dissimilatory sulfur metabolism. Those four genes for hypothetical proteins that exhibited the strongest increases of mRNA levels on sulfide and elemental sulfur, respectively, were chosen for inactivation and phenotypic analyses of the respective mutant strains. This approach verified the importance of the encoded proteins for sulfur globule formation during the oxidation of sulfide and thiosulfate and thereby also documented the suitability of comparative transcriptomics for the identification of new sulfur-related genes in anoxygenic phototrophic sulfur bacteria. PMID:23873913

  7. Synthesis and characterization of porous metal oxides and desulfurization studies of sulfur containing compounds

    NASA Astrophysics Data System (ADS)

    Garces Trujillo, Hector Fabian

    This thesis contains two parts: 1) synthesis and characterization of porous metal oxides that include zinc oxide and a porous mixed-valent manganese oxide with an amorphous structure (AMO) 2) the desulfurization studies for the removal of sulfur compounds. Zinc oxide with different nano-scale morphologies may result in various porosities with different adsorption capabilities. A tunable shape microwave synthesis of ZnO nano-spheres in a co-solvent mixture is presented. The ZnO nano-sphere material is investigated as a desulfurizing sorbent in a fixed bed reactor in the temperature range 200 to 400 °C and compared with ZnO nanorods and platelet-like morphologies. Fresh and sulfided materials were characterized by X-ray diffraction (XRD), BET specific surface area, pore volume, scanning electron microscopy (SEM), X-ray energy dispersive spectroscopy (SEM/EDX), Raman spectroscopy, and thermogravimetric analysis (TGA). The tunable shape microwave synthesis of ZnO presents a high sulfur sorption capacity at temperatures as low as 200 °C which accounts for a three and four fold enhancement over the other preparations presented in this work, and reached 76 % of the theoretical sulfur capacity (TSC) at 300 °C. Another ZnO material with a bimodal micro- and mesopore size distribution investigated as a desulfurizing sorbent presents a sorption capacity that reaches 87% of the theoretical value for desulfurization at 400 °C at breakthrough time. A deactivation model that considers the activity of the solid reactant was used to fit the experimental data. Good agreement between the experimental breakthrough curves and the model predictions are obtained. Manganese oxides are a type of metal oxide materials commonly used in catalytic applications. Little is known about the adsorption capabilities for the removal of sulfur compounds. One of these manganese oxides; amorphous manganese oxide (AMO) is highly promising material for low temperature sorption processes. Amorphous manganese oxide (AMO) has been used in catalytic processes such as for the catalytic oxidation of benzyl alcohol, the preferential oxidation of CO, and for the capture of formate species. This chapter explores the possibility of using AMO in sorption processes for the removal of two contaminants; H 2S and COS in the temperature range 200 - 400 °C.

  8. ADVANCED SULFUR CONTROL CONCEPTS

    SciTech Connect

    Apostolos A. Nikolopoulos; Santosh K. Gangwal; William J. McMichael; Jeffrey W. Portzer

    2003-01-01

    Conventional sulfur removal in integrated gasification combined cycle (IGCC) power plants involves numerous steps: COS (carbonyl sulfide) hydrolysis, amine scrubbing/regeneration, Claus process, and tail-gas treatment. Advanced sulfur removal in IGCC systems involves typically the use of zinc oxide-based sorbents. The sulfides sorbent is regenerated using dilute air to produce a dilute SO{sub 2} (sulfur dioxide) tail gas. Under previous contracts the highly effective first generation Direct Sulfur Recovery Process (DSRP) for catalytic reduction of this SO{sub 2} tail gas to elemental sulfur was developed. This process is currently undergoing field-testing. In this project, advanced concepts were evaluated to reduce the number of unit operations in sulfur removal and recovery. Substantial effort was directed towards developing sorbents that could be directly regenerated to elemental sulfur in an Advanced Hot Gas Process (AHGP). Development of this process has been described in detail in Appendices A-F. RTI began the development of the Single-step Sulfur Recovery Process (SSRP) to eliminate the use of sorbents and multiple reactors in sulfur removal and recovery. This process showed promising preliminary results and thus further process development of AHGP was abandoned in favor of SSRP. The SSRP is a direct Claus process that consists of injecting SO{sub 2} directly into the quenched coal gas from a coal gasifier, and reacting the H{sub 2}S-SO{sub 2} mixture over a selective catalyst to both remove and recover sulfur in a single step. The process is conducted at gasifier pressure and 125 to 160 C. The proposed commercial embodiment of the SSRP involves a liquid phase of molten sulfur with dispersed catalyst in a slurry bubble-column reactor (SBCR).

  9. The Phases of Sulfur.

    ERIC Educational Resources Information Center

    Birdwhistell, Kurt R.

    1995-01-01

    Presents a demonstration that illustrates the dramatic changes that sulfur undergoes upon heating to 200 degrees centigrade and then cooling to room temperature. Supplements the demonstration of the rubberlike properties of catenasulfur made by rapid cooling of the sulfur melt in ice water. (JRH)

  10. Emission of volatile sulfur compounds during composting of municipal solid waste (MSW)

    SciTech Connect

    Zhang, Hongyu [Beijing Building Materials Academy of Science Research/State Key Laboratory of Solid Waste Reuse for Building Material, Beijing 100041 (China); College of Resources and Environment Sciences, China Agricultural University, Beijing 100094 (China); Schuchardt, Frank [Johann Heinrich von Thuenen-Institute, Institute of Agricultural Technology and Biosystems Engineering, Bundesallee 50, 38116 Braunschweig (Germany); Li, Guoxue, E-mail: ligx@cau.edu.cn [College of Resources and Environment Sciences, China Agricultural University, Beijing 100094 (China); Yang, Jinbing; Yang, Qingyuan [College of Resources and Environment Sciences, China Agricultural University, Beijing 100094 (China)

    2013-04-15

    Highlights: ? We compare the volatile sulfur compounds (VSCs) emissions during three types of municipal solid wastes (MSWs) composting. ? The VSCs released from the kitchen waste composting was significantly higher than that from 15–80 mm fraction of MSW. ? Among the five VSCs, H{sub 2}S was the most abundant compound with 39.0–43.0% of total VSCs released. ? Addition of 20% cornstalks could significantly reduce the VSCs emissions during kitchen waste composting. - Abstract: Volatile sulfur compounds (VSCs) are the main source for malodor from composting plants. In this study, the VSCs generated from composting of 15–80 mm municipal solid waste (T0), kitchen waste (T1) and kitchen waste mixed dry cornstalks (T2) were measured in 60 L reactors with forced aeration for a period of 30 days. The VSCs detected in all treatments were hydrogen sulfide (H{sub 2}S), methyl mercaptan (MM), dimethyl sulfide (DMS), carbon bisulfide (CS{sub 2}) and dimethyl disulfide (DMDS). Over 90% of the VSCs emissions occurred during the first 15 days, and reached their peak values at days 4–7. The emission profiles of five VSCs species were significantly correlated with internal materials temperature and outlet O{sub 2} concentration (p < 0.05). Total emissions of the VSCs were 216.1, 379.3 and 126.0 mg kg{sup ?1} (dry matter) for T0, T1 and T2, respectively. Among the five VSCs, H{sub 2}S was the most abundant compound with 39.0–43.0% of total VSCs released. Composting of kitchen waste from separate collection posed a negative influence on the VSC and leachate production because of its high moisture content. An addition of dry cornstalks at a mixing ratio of 4:1 (wet weight) could significantly reduce the VSCs emissions and avoid leachate. Compared to pure kitchen waste, VSCs were reduced 66.8%.

  11. Elemental sulfur recovery process

    DOEpatents

    Flytzani-Stephanopoulos, M.; Zhicheng Hu.

    1993-09-07

    An improved catalytic reduction process for the direct recovery of elemental sulfur from various SO[sub 2]-containing industrial gas streams. The catalytic process provides combined high activity and selectivity for the reduction of SO[sub 2] to elemental sulfur product with carbon monoxide or other reducing gases. The reaction of sulfur dioxide and reducing gas takes place over certain catalyst formulations based on cerium oxide. The process is a single-stage, catalytic sulfur recovery process in conjunction with regenerators, such as those used in dry, regenerative flue gas desulfurization or other processes, involving direct reduction of the SO[sub 2] in the regenerator off gas stream to elemental sulfur in the presence of a catalyst. 4 figures.

  12. Elemental sulfur recovery process

    DOEpatents

    Flytzani-Stephanopoulos, Maria (Winchester, MA); Hu, Zhicheng (Somerville, MA)

    1993-01-01

    An improved catalytic reduction process for the direct recovery of elemental sulfur from various SO.sub.2 -containing industrial gas streams. The catalytic process provides combined high activity and selectivity for the reduction of SO.sub.2 to elemental sulfur product with carbon monoxide or other reducing gases. The reaction of sulfur dioxide and reducing gas takes place over certain catalyst formulations based on cerium oxide. The process is a single-stage, catalytic sulfur recovery process in conjunction with regenerators, such as those used in dry, regenerative flue gas desulfurization or other processes, involving direct reduction of the SO.sub.2 in the regenerator off gas stream to elemental sulfur in the presence of a catalyst.

  13. Reduced sulfur compounds in the atmosphere of sewer networks in Australia: geographic (and seasonal) variations.

    PubMed

    Wang, B; Sivret, E C; Parcsi, G; Le, N M; Kenny, S; Bustamante, H; Stuetz, R M

    2014-01-01

    The management of odorous emissions from sewer networks has become an important issue for sewer system operators resulting in the need to better understand the composition of reduced sulfur compounds (RSCs). Gaseous RSCs including hydrogen sulfide (H2S), methanethiol (MeSH), dimethyl sul?de (DMS), carbon disul?de (CS2), dimethyl disul?de (DMDS) and dimethyl trisulfide (DMTS) were measured in the atmosphere of selected sewer networks in two major Australian cities (Sydney and Melbourne) during 2011-2012. The RSC concentrations in the sewer air were detected in a highly variable range. H2S and MeSH were found at the highest concentrations, followed by DMS (39.2-94.0 ?g/m(3)), CS2 (18.3-19.6 ?g/m(3)), DMDS (7.8-49.6 ?g/m(3)) and DMTS (10.4-35.3 ?g/m(3)). Temporal trends in the occurrence of targeted RSCs were observed and the highest sulfur concentration occurred either in summer or spring, which are typically regarded as the warmer seasons. Statistical significant difference in the magnitude of targeted RSCs was found between samples collected in Sydney and Melbourne. PMID:24647180

  14. Regional river sulfur runoff

    SciTech Connect

    Husar, R.B.; Husar, J.D.

    1985-01-20

    The water and sulfur runoff data for 54 large river basins were assembled, covering 65% of the nondesert land area of the world. The sulfur concentration ranges from 0.5 mg S/L for the West African rivers Niger and Volta to 100 mg S/L in the Colorado River; the world average is 3.2 mg S/L. The concentrations in central and eastern Europe as well as central and eastern North America exceed 8 mg S/L. The sulfur runoff density is also highest in the river basins over these industrialized regions, exceeding 2 g S/m/sup 2//yr. However, high sulfur runoff density in excess of 3 g S/m/sup 2//yr is also measured over the Pacific islands New Zealand and New Guinea and the archipelagos of Indonesia and the Philippines. The natural background sulfur runoff was estimated by assuming that South America, Africa, Australia, and the Pacific Islands are unperturbed by man and that the average river sulfur concentration is in the range 1--3 mg S/L. Taking these background concentration values, the man-induced sulfur runoff for Europe ranges between 2 and 8 times the natural flow, and over North America, man's contribution ranges between 1 and 5 times the natural runoff. The global sulfur flow from nondesert land to the oceans and the Caspian Sea is estimated as 131 Tg S/yr, of which 46--85 Tg S/yr is attributed to natural causes. The regional river sulfur runoff pattern discussed in this paper does not have enough spatial resolution to be directly applicable to studies of the environmental effects of man-induced sulfur flows. However, it points to the continental-size regions where those perturbations are most evident and to the magnitude of the perturbations as expressed in units of the natural flows.

  15. Specificity of respiratory pathways involved in the reduction of sulfur compounds by Salmonella enterica

    Microsoft Academic Search

    Andrew P. Hinsley; Ben C. Berks

    The tetrathionate (Ttr) and thiosulfate (Phs) reductases of Salmonella enterica LT2, together with the polysulfide reductase (Psr) of Wolinella succinogenes, are unusual examples of enzymes containing a molybdopterin active-site cofactor since all formally catalyse sulfur-sulfur bond cleavage. This is in contrast to the oxygen or hydrogen transfer reactions exhibited by other molybdopterin enzymes. Here the catalytic specificity of Ttr and

  16. The influence of hydroxyl volatile organic compounds on the oxidation of aqueous sulfur dioxide by oxygen.

    PubMed

    Dhayal, Yogpal; Chandel, C P S; Gupta, K S

    2014-07-01

    Although the effect of volatile organic compounds (VOCs) on the oxidation of dissolved sulfur dioxide by oxygen has been the subject of many investigations, this is the first study which examines the effect of a large number of precisely 16 hydroxy compounds. The kinetics both in the absence and the presence of VOCs was defined by rate laws (A and B): -d[S(IV)]dt = R? = k?[S(IV)] (A) -d[S(IV)]dt = R(i) = k(i)[S(IV)] (B) where R? and k? are the initial rate and first-order rate constant, respectively, in the absence of VOCs, R(i), and k(i) are the initial rate and the first-order rate constant, respectively, in the presence of VOCs, and [S(IV)] is the concentration of dissolved sulfur dioxide, sulfur(IV). The nature of the dependence of k(i) on the concentration of inhibitor, [Inh], was defined by Eq. (C). [k(i) = k?/(1 + B[Inh]) (C) where B is an empirical inhibition parameter. The values of B have been determined from the plots of 1/k(i) versus [Inh]. Among aliphatic and aromatic hydroxy compounds studied, t-butyl alcohol and pinacol were without any inhibition effect due to the absence of secondary or tertiary hydrogen. The values of inhibition parameter, B, were related to k(inh), the rate constant for the reaction of SO?(-) radical with the inhibitor, by Eq. (D). B = (9 ± 2) x 10?? x k(inh) (D) Equation (D) may be used to calculate the values of either of B or k(inh) provided that the other is known. The extent of inhibition depends on the value of the composite term, B[Inh]. However, in accordance with Eq. (C), the extent of inhibition would be sizeable and measurable when B[Inh]?> 0.1 and oxidation of S(IV) would be almost completely stopped when B[Inh]???10. B[Inh] value can be used as a guide whether the reaction step: SO4 (-)?+ organics???SO?(2-)?+ non-chain products: should be included in the multiphase models or not. PMID:24638831

  17. Compounds with mixed and intermediate sulfur valences as precursors of banded sulfides in carbonate-hosted Zn-Pb deposits in Belgium and Poland

    Microsoft Academic Search

    H. Kucha; W. Viaene

    1993-01-01

    Compounds of Fe, Pb and Zn with mixed and intermediate sulfur valences form ubiquitous inclusions and relics in banded sphalerite, pyrite-melnikovite and galena. Banded sulfides continuously grade into banded compounds with mixed and intermediate sulfur valences, the latter with a fibrous microtexture. A fibrous microtexture is also shown by banded sphalerite and pyrite from Zn-Pb deposits of Belgium and Poland.

  18. Quantitative structure-property relationship study of normal boiling points for halogen-\\/ oxygen-\\/ sulfur-containing organic compounds using the CODESSA program

    Microsoft Academic Search

    Ovidiu Ivanciuc; Teodora Ivanciuc; Alexandru T. Balaban

    1998-01-01

    QSPR (Quantitative Structure-Property Relationship) models for the estimation of boiling points of organic compounds containing halogens, oxygen, or sulfur without hydrogen bonding were established with the CODESSA (Comprehensive Descriptors for Structural and Statistical Analysis) program developed by Katritzky and coworkers. The boiling points of 185 compounds containing oxygen or sulfur can be accurately computed with a MLR (Multi-Linear Regression) equation

  19. Sulfuric Acid on Europa

    NASA Technical Reports Server (NTRS)

    1999-01-01

    Frozen sulfuric acid on Jupiter's moon Europa is depicted in this image produced from data gathered by NASA's Galileo spacecraft. The brightest areas, where the yellow is most intense, represent regions of high frozen sulfuric acid concentration. Sulfuric acid is found in battery acid and in Earth's acid rain.

    This image is based on data gathered by Galileo's near infrared mapping spectrometer.

    Europa's leading hemisphere is toward the bottom right, and there are enhanced concentrations of sulfuric acid in the trailing side of Europa (the upper left side of the image). This is the face of Europa that is struck by sulfur ions coming from Jupiter's innermost moon, Io. The long, narrow features that crisscross Europa also show sulfuric acid that may be from sulfurous material extruded in cracks.

    Galileo, launched in 1989, has been orbiting Jupiter and its moons since December 1995. JPL manages the Galileo mission for NASA's Office of Space Science, Washington DC. JPL is a division of the California Institute of Technology, Pasadena, CA.

  20. Molecular detection and isolation from antarctica of methylotrophic bacteria able to grow with methylated sulfur compounds.

    PubMed

    Moosvi, S Azra; McDonald, Ian R; Pearce, David A; Kelly, Donovan P; Wood, Ann P

    2005-08-01

    This study is the first demonstration that a diverse facultatively methylotrophic microbiota exists in some Antarctic locations. PCR amplification of genes diagnostic for methylotrophs was carried out with bacterial DNA isolated from 14 soil and sediment samples from ten locations on Signy Island, South Orkney Islands, Antarctica. Genes encoding the mxaF of methanol dehydrogenase, the fdxA for Afipia ferredoxin, the msmA of methanesulfonate monooxygenase, and the 16S rRNA gene of Methylobacterium were detected in all samples tested. The mxaF gene sequences corresponded to those of Hyphomicrobium, Methylobacterium, and Methylomonas. Over 30 pure cultures of methylotrophs were isolated on methanesulfonate, dimethylsulfone, or dimethylsulfide from ten Signy Island lakes. Some were identified from 16S rRNA gene sequences (and morphology) as Hyphomicrobium species, strains of Afipia felis, and a methylotrophic Flavobacterium strain. Antarctic environments thus contain diverse methylotrophic bacteria, growing on various C1-substrates, including C1-sulfur compounds. PMID:16104352

  1. Comparison of volatile sulfur compound concentrations measured with a sulfide detector vs. gas chromatography.

    PubMed

    Furne, J; Majerus, G; Lenton, P; Springfield, J; Levitt, D G; Levitt, M D

    2002-02-01

    The accuracy of the Halimeter, an inexpensive, simple instrument that measures total breath volatile sulfur compounds (VSCs), has not been adequately tested. We compared Halimeter measurements with those obtained with a specific and sensitive gas chromatographic (GC) technique. The Halimeter gave different, biexponential responses to a constant concentration of different VSCs: The relative response rate and sensitivity were hydrogen sulfide > methyl mercaptan > dimethylsulfide. The transient peak VSC concentration of oral samples was reached long before the sulfide detector fully responded. The GC measurement of initial total VSCs in breath samples was 2.7+/-0.48 times greater than the peak concentration of the Halimeter. However, the plateau phase measurement of the Halimeter was 25% greater than that of GC. While GC and Halimeter measurements positively correlated, appreciable differences were observed. In studies where relatively precise VSC measurements are required, GC is the preferable technique. PMID:11827259

  2. The effect of a mouthrinse containing chlorine dioxide in the clinical reduction of volatile sulfur compounds.

    PubMed

    Soares, Leo Guimaraes; Guaitolini, Roberto Luiz; Weyne, Sergio de Carvalho; Falabella, Marcio Eduardo Vieira; Tinoco, Eduardo Muniz Barretto; da Silva, Denise Gomes

    2013-07-01

    This study sought to evaluate the clinical effect of a mouthrinse containing 0.3% chlorine dioxide (ClO2) in reducing oral volatile sulfur compounds (VSC). Halitosis was induced by L-cysteine in 11 volunteers, and 4 solutions were compared: a test solution containing 0.3% ClO2, 0.07% cetylpyridinium chloride (CPC), and 0.05% sodium fluoride; a placebo; a solution containing 0.05% CPC; and a control solution of 0.2% chlorhexidine gluconate (CHX). VSC levels were assessed using a Halimeter, and 6 measurements were made from baseline to 3 hours postrinse. The VSC reduction rate of the test mouthrinse was superior to the placebo and the CPC solution. There was no difference between the test solution and the CHX solution in VSC reduction rates immediately postrinse, or at 2 and 3 hours postrinse; both solutions were statistically superior to the placebo and the CPC solution. PMID:23823344

  3. The relative importance of sulfur and nitrogen compounds in the acidification of freshwater

    SciTech Connect

    Van Miegroet, H.

    1992-08-01

    The acid-base chemistry of streams and lakes is regulated by the amount and composition of atmospheric deposition and by biogeochemical processes in the catchment and within streams and lakes. In this paper the influence of nitrogen (N) and sulfur (S) compounds will be discussed (a) because they are major constituents of atmospheric deposition that have recently become the focus of critical loads assessments in Europe and North America, and (b) because they are essential nutrients for most biota and cycle naturally through terrestrial and aquatic ecosystems. In order to evaluate the relative impact of atmospheric inputs on freshwater acidity, it is necessary to clearly define ``acidification`` and to understand; the mechanisms of change caused or mediated by natural and anthropogenic processes.

  4. CATALYTIC OXIDATION OF TOTAL REDUCED SULFUR COMPOUNDS FROM PULP AND PAPER INDUSTRIES WITH OZONE AS AN OXIDANT

    EPA Science Inventory

    Pulp and paper industry generates more than 144 million lb of VOCs per year including a range of reduced sulfur compounds (TRS) such as dimethyl sulfide (DMS), dimethyl disulfide (DMDS), methane thiol (MT) and H2S that are odorous, toxic and contribute to smog formation. Thermal ...

  5. Effects of oil drops containing Lactobacillus salivarius WB21 on periodontal health and oral microbiota producing volatile sulfur compounds

    Microsoft Academic Search

    Nao Suzuki; Kazunari Tanabe; Toru Takeshita; Masahiro Yoneda; Tomoyuki Iwamoto; Sueko Oshiro; Yoshihisa Yamashita; Takao Hirofuji

    2012-01-01

    The objective of this paper is to evaluate the effects of oil drops containing Lactobacillus salivarius WB21 on periodontal health and oral microbiota producing volatile sulfur compounds (VSCs). For this study, 42 subjects were randomly assigned to receive oil samples containing L. salivarius WB21 or a placebo for two weeks. Oral assessment and saliva collection were performed on days 1

  6. Kinetics of oxidation of odorous sulfur compounds in aqueous alkaline solution with H2O2.

    PubMed

    Feliers, C; Patria, L; Morvan, J; Laplanche, A

    2001-10-01

    Sulfur species oxidation is a crucial issue wastewater treatment. The production of sulfur compounds like H2S,CH3SH, C2H5SH, disulfides and dimethyle sulfide generates odorous nuisances for the neighborhood. The oxidation of these species by H2O2 in alkaline solution has been investigated. The results showed that thiols CH3SH and C2H5SH react with H202 only in their dissociated form RS- with rate constants respectively k = 8.81 +/- 0.48 M-1s-1 and 8.37 +/- 0.63 M-1.s-1. Mercaptans oxidation produces 100 % of dimethyldisulfide or diethyldisulfide. The oxidation of disulfides shows a difference of reactivity between H2O2 and HO2- towards sulfur species. Increasing the pH accelerates significantly the reactions in the case of CH3SSCH3. The oxidation rate can be described as: r = k[RSSR][H2O2][RSSR][H2O2] + k[RSSR][HO2-] [RSSR][HO2-] with k[RSSR][H2O2] = 1.2 x 10(-4) +/- 0.2 x 10(-4) M-1s-1 and k[RSSR][HO2-] = 3.4 x 10(-4) +/- 0.6 x 10(-4) M-1.s-1 for CH3SSCH3. Dimethyl sulfide presents a reactivity different from disulfides. The oxidation rate can also be described as: r = k[CH3SCH3][H2O21][CH3SCH3][H2O2] + k[CH3SCH3][HO-] [CH3SCH3][HO2-], however, oxidation rate decreases with pH increase. k[CH3SCH3][H2O2] = 12.8 x 10(-3) +/- 0.96 x 10(-3) M-1.s-1 and k[CH3SCH3][HO2-] = 4 x 10(-3) +/- 0.3 x 10(-3) M-1.s-1. PMID:11766036

  7. Selectivity among organic sulfur compounds in one- and two-liquid-phase cultures of Rhodococcus sp. strain JVH1.

    PubMed

    Kirkwood, Kathlyn M; Foght, Julia M; Gray, Murray R

    2007-08-01

    The selectivity of Rhodococcus sp. strain JVH1 among selected sulfidic and thiophenic compounds was investigated in both single-liquid-phase (aqueous) cultures and in two-liquid-phase cultures, where the sulfur compounds were dissolved in 2,2,4,4,6,8,8-heptamethylnonane as the immiscible organic carrier phase. In the single-liquid-phase cultures, Rhodococcus sp. strain JVH1 showed a preference for benzyl sulfide over both 1,4-dithiane and benzothiophene. An increased lag was observed in the degradation of benzyl sulfone and benzothiophene sulfone when both compounds were present. These results were consistent with a competitive inhibition mechanism, affecting both sulfur oxidation and carbon-sulfur bond cleavage. In the two-liquid-phase cultures, the effect of partitioning between the two liquid phases dominated the desulfurization activity of the culture. This partitioning resulted in an apparent absence of selectivity, as well as decreases in lag time, extent of degradation, and time to completion of degradation. Desulfurization activity also depended on the growth phase of the cultures. Mass transfer rate limitations were not observed at the low degradation rates of 0.02 mmol day(-1) l(-1). Owing to the importance of partitioning, Rhodococcus sp. strain JVH1 is predicted to show nonselective activity towards the sulfur species in a whole crude oil. PMID:17091345

  8. 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...

  9. 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 ...

  10. Effects of food materials on removal of Allium-specific volatile sulfur compounds.

    PubMed

    Negishi, Osamu; Negishi, Yukiko; Ozawa, Tetsuo

    2002-06-19

    Effects of food materials were investigated on removal of several kinds of thiols, sulfides, and disulfides, which arise from vegetables of Allium species during food preparation and eating. Methanethiol, propanethiol, and 2-propenethiol were captured by raw foods such as fruits, vegetables, and mushrooms or a mixture of their acetone powders and phenolic compounds. The odor of diallyl disulfide was remarkably reduced by kiwi fruit, spinach, cutting lettuce, parsley, basil, mushrooms, and, particularly, cow's milk, raw egg, boiled rice, and bovine serum albumin (BSA). This suggests that the removal of diallyl disulfide could be caused by a physical and chemical interaction between the disulfide and foods. Furthermore, milk and BSA captured propanethiol, 2-propenethiol, dipropyl sulfide, diallyl sulfide, dimethyl disulfide, and dipropyl disulfide very well. An enzymatic degradation of diallyl disulfide by spinach and asparagus was also observed. These results demonstrate that the deodorization with foods is achieved by multiple actions including physical and chemical interaction between volatile sulfur compounds and foods, enzymatic degradation of disulfides, and addition of thiols to polyphenolic compounds, catalyzed by polyphenol oxidases or peroxidases. PMID:12059171

  11. Bacterial ethane formation from reduced, ethylated sulfur compounds in anoxic sediments

    USGS Publications Warehouse

    Oremland, R.S.; Whiticar, Michael J.; Strohmaier, F.E.; Kiene, R.P.

    1988-01-01

    Trace levels of ethane were produced biologically in anoxic sediment slurries from five chemically different aquatic environments. Gases from these locations displayed biogenic characteristics, having 12C-enriched values of ??13CH4 (-62 to -86%.), ??13C2H6 (-35 to -55%.) and high ratios (720 to 140,000) of CH4 [C2H6 + C3H8]. Endogenous production of ethane by slurries was inhibited by autoclaving or by addition of the inhibitor of methanogenic bacteria, 2-bromoethanesulfonic acid (BES). Ethane formation was stimulated markedly by ethanethiol (ESH), and, to a lesser extent, by diethylsulfide (DES). Formation of methane and ethane in ESH- or DES-amended slurries was blocked by BES. Experiments showed that ethionine (or an analogous compound) could be a precursor of ESH. Ethylamine or ethanol additions to slurries caused only a minor stimulation of ethane formation. Similarly, propanethiol additions resulted in only a minor enhancement of propane formation. Cell suspensions of a methyltrophic methanogen produced traces of ethane when incubated in the presence of DES, although the organism did not grow on this compound. These results indicate that methanogenic bacteria produce ethane from the traces of ethylated sulfur compounds present in recent sediments. Preliminary estimates of stable carbon isotope fractionation associated with sediment methane formation from dimethylsulfide was about 40%., while ethane formation from DES and ESH was only 4. 6 and 6.5%., respectively. ?? 1988.

  12. An experimental study of sulfur and NOx fluxes over grassland

    Microsoft Academic Search

    B. B. Hicks; M. L. Wesely; R. L. Coulter; R. L. Hart; J. L. Durham; R. Speer; D. H. Stedman

    1986-01-01

    Three independent sulfur sensors were used in a study of sulfur eddy fluxes to a field of wheat stubble and mixed grasses, conducted in Southern Ohio in September, 1979. Two of these sensors were modified commercial instruments; one operated with a prefilter to measure gaseous sulfur compounds and the other with a denuder system to provide submicron particulate sulfur data.

  13. Topsoe`s Wet gas Sulfuric Acid (WSA) process: An alternative technology for recovering refinery sulfur

    SciTech Connect

    Ward, J.W. [Haldor Topsoe, Inc., Houston, TX (United States)

    1995-09-01

    The Topsoe Wet gas Sulfuric Acid (WSA) process is a catalytic process which produces concentrated sulfuric acid from refinery streams containing sulfur compounds such as H{sub 2}S (Claus plant feed), Claus plant tail gas, SO{sub 2} (FCC off-gas, power plants), and spent sulfuric acid (alkylation acid). The WSA process recovers up to 99.97% of the sulfur value in the stream as concentrated sulfuric acid (93--98.5 wt%). No solid waste products or waste water is produced and no chemicals are consumed in the process. The simple process layout provides low capital cost and attractive operating economy. Twenty four commercial WSA plants have been licensed. The WSA process is explained in detail and comparisons with alternative sulfur management technology are presented. Environmental regulations applying to SO{sub x} abatement and sulfuric acid production plants are explained in the context of WSA plant operation.

  14. Geomicrobiological aspects of the oxidation of reduced sulfur compounds by photosynthesizing bacteria.

    PubMed

    Borkowski, Andrzej; Wolicka, Dorota

    2007-01-01

    The activity of photosynthesizing sulfur bacteria in a continuous culture was studied. The bacteria were isolated from the natural environment with the use of the Winogradski column. Isolated bacteria were cultured in synthetic medium and in the effluent from the column containig HS-. Sulphides, the main product of reduction of sulfates in phosphogypsum, were used by green sulfur bacteria in the photosynthetic column. Almost 70% reduction of the concentration of sulfides was observed. After the experiment, diffractometric methods where employed to analyze the sediment from the column. PMID:17419190

  15. THERMAL PROCESSING OF DICTYONEMA ARGILLITE AND KUKERSITE OIL SHALE: TRANSFORMATION AND DISTRIBUTION OF SULFUR COMPOUNDS IN PILOT-SCALE GALOTER PROCESS

    Microsoft Academic Search

    A. ELENURM; V. OJA; E. TALI; E. TEARO; A. YANCHILIN

    2008-01-01

    Transformation and distribution of sulfur compounds in fossil fuel thermal processing depends on the bonding forms of sulfur in the specific feed-stock, thermal processing conditions and the technology used. This paper is focused on oil shale semicoking in a pilot-scale solid heat carrier retort (Galoter process) where oil shale is heated by means of mixing with ash from retorted shale

  16. [Influence of transition metal compounds on superoxide dismutase activity of sulfur reducing Desulfuromonas acetoxidans bacteria].

    PubMed

    Vasyliv, O M; Hnatush, S O

    2013-01-01

    Superoxide dismutase, as one of the enzymes of cells' antioxidant defensive system, catalyzes superoxide anion-radical (O2-) dismutation with O2 and H2O2 forming. The influence of such transition metal compounds, as FeSO4, FeCl3, MnCl2, NiCl2, and CoCl2 on superoxide dismutase activity of sulfur-reducing Desulfuromonas acetoxidans bacteria has been investigated. Maximal activity of the investigated enzyme has been observed accordingly under the influence of 1.0 mM of NiCl2, 2.0 mM of CoCl2 and MnCl2 on the second day and under the influence of 1.0 mM of FeCl3 and FeSO4 respectively, on the third day of growth in comparison with control samples. An increase of incubation time and concentration of metal compound in the medium caused the inhibition of superoxide dismutase activity. PMID:23720962

  17. Emission of volatile sulfur compounds during composting of municipal solid waste (MSW).

    PubMed

    Zhang, Hongyu; Schuchardt, Frank; Li, Guoxue; Yang, Jinbing; Yang, Qingyuan

    2013-04-01

    Volatile sulfur compounds (VSCs) are the main source for malodor from composting plants. In this study, the VSCs generated from composting of 15-80 mm municipal solid waste (T0), kitchen waste (T1) and kitchen waste mixed dry cornstalks (T2) were measured in 60 L reactors with forced aeration for a period of 30 days. The VSCs detected in all treatments were hydrogen sulfide (H2S), methyl mercaptan (MM), dimethyl sulfide (DMS), carbon bisulfide (CS2) and dimethyl disulfide (DMDS). Over 90% of the VSCs emissions occurred during the first 15 days, and reached their peak values at days 4-7. The emission profiles of five VSCs species were significantly correlated with internal materials temperature and outlet O2 concentration (p<0.05). Total emissions of the VSCs were 216.1, 379.3 and 126.0 mg kg(-1) (dry matter) for T0, T1 and T2, respectively. Among the five VSCs, H2S was the most abundant compound with 39.0-43.0% of total VSCs released. Composting of kitchen waste from separate collection posed a negative influence on the VSC and leachate production because of its high moisture content. An addition of dry cornstalks at a mixing ratio of 4:1 (wet weight) could significantly reduce the VSCs emissions and avoid leachate. Compared to pure kitchen waste, VSCs were reduced 66.8%. PMID:23312132

  18. Catalyst Design for the Electrocatalytic Hydrogenation of Model Compounds in the Presence of Sulfur

    NASA Astrophysics Data System (ADS)

    Murphy, Sean

    In this research, the electrocatalytic hydrogenation of 2-cyclohexen-1-one by Ni-Wand W-S catalysts is investigated. The objective was to demonstrate catalytic activity of sulfide-based electrodes for the hydrogenation reaction in the presence of sulfur containing molecules representative of those found in bitumen distillate fractions. Ni and Pd catalysts were investigated as control standards for the hydrogenation reaction. Both catalysts were found to be ineffective in the presence of sulfur. Ni-W composite films supported on aluminum have been shown to be catalytically active for the electrocatalytic hydrogenation of 2-cyclohexen-1-one, but are poisoned in the presence of sulfur. WS2 catalysts particles supported on vitreous carbon have been shown to be active for the electrocatalytic hydrogenation in the presence of sulfur. The ionic liquid 1-butyl-3-methyl-imidazlium tetrafluoroborate was investigated as a solvent for e1ectrocatalytic hydrogenation reactions. It was found to be incompatible with a vitreous carbon anode and reacted immediately producing an insulating film.

  19. Thermodynamic analysis of the process of formation of sulfur compounds in oxygen gasification of coal

    SciTech Connect

    G.Ya. Gerasimov; T.M. Bogacheva [M.V. Lomonosov Moscow State University, Moscow (Russian Federation). Institute of Mechanics

    2001-05-15

    A thermodynamic approach to the description of the behavior of the system fuel-oxidizer in oxygen gasification of coal is used to reveal the main mechanisms of the process of capture of sulfur by the mineral part of the coal and to determine the fundamental possibility of the process for coals from different coal fields.

  20. Process for removing sulfur from coal

    DOEpatents

    Aida, T.; Squires, T.G.; Venier, C.G.

    1983-08-11

    A process is disclosed for the removal of divalent organic and inorganic sulfur compounds from coal and other carbonaceous material. A slurry of pulverized carbonaceous material is contacted with an electrophilic oxidant which selectively oxidizes the divalent organic and inorganic compounds to trivalent and tetravalent compounds. The carbonaceous material is then contacted with a molten caustic which dissolves the oxidized sulfur compounds away from the hydrocarbon matrix.

  1. Process for removing sulfur from coal

    DOEpatents

    Aida, Tetsuo (Ames, IA); Squires, Thomas G. (Gilbert, IA); Venier, Clifford G. (Ames, IA)

    1985-02-05

    A process for the removal of divalent organic and inorganic sulfur compounds from coal and other carbonaceous material. A slurry of pulverized carbonaceous material is contacted with an electrophilic oxidant which selectively oxidizes the divalent organic and inorganic compounds to trivalent and tetravalent compounds. The carbonaceous material is then contacted with a molten caustic which dissolves the oxidized sulfur compounds away from the hydrocarbon matrix.

  2. Need total sulfur content? Use chemiluminescence

    SciTech Connect

    Kubala, S.W.; Campbell, D.N. [Fluid Data, Inc., Angleton, TX (United States); DiSanzo, F.P. [Mobil Technology Co., Paulsboro, NJ (United States)

    1996-09-01

    Regulations issued by the United States Environmental Protection Agency require petroleum refineries to reduce or control the amount of total sulfur present in their refined products. These legislative requirements have led many refineries to search for online instrumentation that can produce accurate and repeatable total sulfur measurements within allowed levels. Several analytical methods currently exist to measure total sulfur content. They include X-ray fluorescence (XRF), microcoulometry, lead acetate tape, and pyrofluorescence techniques. Sulfur-specific chemiluminescence detection (SSCD) has recently received much attention due to its linearity, selectivity, sensitivity, and equimolar response. However, its use has been largely confined to the area of gas chromatography. This article focuses on the special design considerations and analytical utility of an SSCD system developed to determine total sulfur content in gasoline. The system exhibits excellent linearity and selectivity, the ability to detect low minimum levels, and an equimolar response to various sulfur compounds. 2 figs., 2 tabs.

  3. 40 CFR 50.4 - National primary ambient air quality standards for sulfur oxides (sulfur dioxide).

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...quality standards for sulfur oxides (sulfur dioxide). 50...quality standards for sulfur oxides (sulfur dioxide). ...rounded up). (c) Sulfur oxides shall be measured in the...arithmetic mean and the second-highest 24-hour averages...

  4. 40 CFR 50.4 - National primary ambient air quality standards for sulfur oxides (sulfur dioxide).

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...quality standards for sulfur oxides (sulfur dioxide). Link...rounded up). (c) Sulfur oxides shall be measured in the...arithmetic mean and the second-highest 24-hour averages must...quality standards for sulfur oxides (sulfur dioxide)....

  5. 40 CFR 50.5 - National secondary ambient air quality standard for sulfur oxides (sulfur dioxide).

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...quality standard for sulfur oxides (sulfur dioxide). 50...quality standard for sulfur oxides (sulfur dioxide...rounded up). (b) Sulfur oxides shall be measured in the...demonstrate attainment, the second-highest 3-hour average...

  6. 40 CFR 50.4 - National primary ambient air quality standards for sulfur oxides (sulfur dioxide).

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...quality standards for sulfur oxides (sulfur dioxide). 50...quality standards for sulfur oxides (sulfur dioxide). ...rounded up). (c) Sulfur oxides shall be measured in the...arithmetic mean and the second-highest 24-hour averages...

  7. 40 CFR 50.5 - National secondary ambient air quality standard for sulfur oxides (sulfur dioxide).

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...quality standard for sulfur oxides (sulfur dioxide). 50...quality standard for sulfur oxides (sulfur dioxide...rounded up). (b) Sulfur oxides shall be measured in the...demonstrate attainment, the second-highest 3-hour average...

  8. 40 CFR 50.4 - National primary ambient air quality standards for sulfur oxides (sulfur dioxide).

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...quality standards for sulfur oxides (sulfur dioxide). 50...quality standards for sulfur oxides (sulfur dioxide). ...rounded up). (c) Sulfur oxides shall be measured in the...arithmetic mean and the second-highest 24-hour averages...

  9. 40 CFR 50.5 - National secondary ambient air quality standard for sulfur oxides (sulfur dioxide).

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...quality standard for sulfur oxides (sulfur dioxide). 50...quality standard for sulfur oxides (sulfur dioxide...rounded up). (b) Sulfur oxides shall be measured in the...demonstrate attainment, the second-highest 3-hour average...

  10. 40 CFR 50.4 - National primary ambient air quality standards for sulfur oxides (sulfur dioxide).

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...quality standards for sulfur oxides (sulfur dioxide). 50...quality standards for sulfur oxides (sulfur dioxide). ...rounded up). (c) Sulfur oxides shall be measured in the...arithmetic mean and the second-highest 24-hour averages...

  11. 40 CFR 50.5 - National secondary ambient air quality standard for sulfur oxides (sulfur dioxide).

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...quality standard for sulfur oxides (sulfur dioxide). 50...quality standard for sulfur oxides (sulfur dioxide...rounded up). (b) Sulfur oxides shall be measured in the...demonstrate attainment, the second-highest 3-hour average...

  12. 40 CFR 50.5 - National secondary ambient air quality standard for sulfur oxides (sulfur dioxide).

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...quality standard for sulfur oxides (sulfur dioxide). 50...quality standard for sulfur oxides (sulfur dioxide...rounded up). (b) Sulfur oxides shall be measured in the...demonstrate attainment, the second-highest 3-hour average...

  13. Sodium sulfur battery seal

    DOEpatents

    Mikkor, Mati (Ann Arbor, MI)

    1981-01-01

    This disclosure is directed to an improvement in a sodium sulfur battery construction in which a seal between various battery compartments is made by a structure in which a soft metal seal member is held in a sealing position by holding structure. A pressure applying structure is used to apply pressure on the soft metal seal member when it is being held in sealing relationship to a surface of a container member of the sodium sulfur battery by the holding structure. The improvement comprises including a thin, well-adhered, soft metal layer on the surface of the container member of the sodium sulfur battery to which the soft metal seal member is to be bonded.

  14. Influence of anxiety on the production of oral volatile sulfur compounds.

    PubMed

    Calil, Caroline Morini; Marcondes, Fernanda Klein

    2006-07-10

    Since many patients complain about halitosis without there being any clinical evidence of its cause, psychological symptoms have been pointed out as halitosis-inducing factors. The aim of this study was to evaluate the influence of anxiety on the production of volatile sulfur compounds (VSC). Seventeen undergraduate men in good oral and general health participated in this study, after approval by the ethics committee. The volunteers were requested to refrain from toothbrushing, using mouth rinse and eating on the experimental day. Before presenting the anxiogenic condition, the volunteer was asked to fill out the Beck Anxiety Inventory questionnaire, to check whether he had been exposed to stressors during the previous week. The Video-Recorded Stroop Color-Word Test (VRSCWT) was used to elicit anxiety. The VSC (halimeter), blood pressure, heart rate and salivary flow measurements were taken before and after the VRSCWT. The volunteers presented a minimal or slight level of anxiety before the test. There was an increase in the oral concentration of VSC, Systolic Blood Pressure and of heart rate (p < 0.05) after the VRSCWT, and no changes in the salivary flow. The results of the present study showed that the anxiogenic condition (VRSCWT) induced increases in VSC concentration, which might contribute to halitosis. PMID:16564550

  15. Regulation of a Novel Acidithiobacillus caldus Gene Cluster Involved in Metabolism of Reduced Inorganic Sulfur Compounds?

    PubMed Central

    Rzhepishevska, Olena I.; Valdés, Jorge; Marcinkeviciene, Liucija; Gallardo, Camelia Algora; Meskys, Rolandas; Bonnefoy, Violaine; Holmes, David S.; Dopson, Mark

    2007-01-01

    Acidithiobacillus caldus has been proposed to play a role in the oxidation of reduced inorganic sulfur compounds (RISCs) produced in industrial biomining of sulfidic minerals. Here, we describe the regulation of a new cluster containing the gene encoding tetrathionate hydrolase (tetH), a key enzyme in the RISC metabolism of this bacterium. The cluster contains five cotranscribed genes, ISac1, rsrR, rsrS, tetH, and doxD, coding for a transposase, a two-component response regulator (RsrR and RsrS), tetrathionate hydrolase, and DoxD, respectively. As shown by quantitative PCR, rsrR, tetH, and doxD are upregulated to different degrees in the presence of tetrathionate. Western blot analysis also indicates upregulation of TetH in the presence of tetrathionate, thiosulfate, and pyrite. The tetH cluster is predicted to have two promoters, both of which are functional in Escherichia coli and one of which was mapped by primer extension. A pyrrolo-quinoline quinone binding domain in TetH was predicted by bioinformatic analysis, and the presence of an o-quinone moiety was experimentally verified, suggesting a mechanism for tetrathionate oxidation. PMID:17873067

  16. Regulation of a novel Acidithiobacillus caldus gene cluster involved in metabolism of reduced inorganic sulfur compounds.

    PubMed

    Rzhepishevska, Olena I; Valdés, Jorge; Marcinkeviciene, Liucija; Gallardo, Camelia Algora; Meskys, Rolandas; Bonnefoy, Violaine; Holmes, David S; Dopson, Mark

    2007-11-01

    Acidithiobacillus caldus has been proposed to play a role in the oxidation of reduced inorganic sulfur compounds (RISCs) produced in industrial biomining of sulfidic minerals. Here, we describe the regulation of a new cluster containing the gene encoding tetrathionate hydrolase (tetH), a key enzyme in the RISC metabolism of this bacterium. The cluster contains five cotranscribed genes, ISac1, rsrR, rsrS, tetH, and doxD, coding for a transposase, a two-component response regulator (RsrR and RsrS), tetrathionate hydrolase, and DoxD, respectively. As shown by quantitative PCR, rsrR, tetH, and doxD are upregulated to different degrees in the presence of tetrathionate. Western blot analysis also indicates upregulation of TetH in the presence of tetrathionate, thiosulfate, and pyrite. The tetH cluster is predicted to have two promoters, both of which are functional in Escherichia coli and one of which was mapped by primer extension. A pyrrolo-quinoline quinone binding domain in TetH was predicted by bioinformatic analysis, and the presence of an o-quinone moiety was experimentally verified, suggesting a mechanism for tetrathionate oxidation. PMID:17873067

  17. Effects of Streptococcus thermophilus on volatile sulfur compounds produced by Porphyromonas gingivalis.

    PubMed

    Lee, Sung-Hoon; Baek, Dong-Heon

    2014-11-01

    Halitosis as oral malodour is an unpleasant odour caused by volatile sulfur compounds (VSCs). VSCs are produced primarily by anaerobic bacteria that abundantly produce proteinase as trypsin-like enzyme. General therapies, such as mouthwash and plaque control, do not provide a continuous effect on oral halitosis. Streptococcus thermophilus is a probiotic bacterium that is beneficial for human health. The aim of this study was to evaluate the effect of S. thermophilus on Porphyromonas gingivalis-producing VSCs and to analyze the inhibitory mechanism of halitosis. P. gingivalis was cultured with or without S. thermophilus, and the emission of VSCs from the spent culture medium was measured by gas chromatography. In order to analyze the inhibitory effect, the antibacterial activity of S. thermophilus against P. gingivalis was assessed. After the spent culture medium or whole bacterial of S. thermophilus was mixed with the spent culture medium of P. gingivalis, VSCs were again measured by gas chromatograph. When S. thermophilus and P. gingivalis were co-cultivated, VSCs were present at a lower level than those of single-cultured P. gingivalis. S. thermophilus inhibited growth of P. gingivalis, and the whole bacteria and the spent culture medium of S. thermophilus reduced emission of VSCs gas. S. thermophilus may reduce oral malodour by inhibition of P. gingivalis growth and neutralizing VSCs with their metabolites or themselves. PMID:25105253

  18. In vitro growth characteristics and volatile sulfur compound production of Solobacterium moorei.

    PubMed

    Stephen, Abish S; Naughton, Declan P; Pizzey, Robert L; Bradshaw, David J; Burnett, Gary R

    2014-04-01

    Solobacterium moorei has recently been implicated as a causative agent of halitosis. In vitro experiments to evaluate the role of S. moorei in halitosis have, however, been complicated by a paucity of information on the ideal conditions for culturing this organism. This work aimed to optimize a liquid culture medium for S. moorei, and to determine the growth-curve of the organism. Further, the ability of S. moorei to generate volatile sulfur compounds was investigated and compared quantitatively to other oral anaerobes by an optimized head-space gas chromatography method. Serum-supplementation of standard liquid growth media gave greater growth of S. moorei than non-supplemented broths, with the best medium found to be serum-supplemented tryptone soya broth. S. moorei was able to metabolize cysteine directly to hydrogen sulfide, but was unable to produce methanethiol from methionine. S. moorei produced 2-3 times more hydrogen sulfide (normalized for colony forming units) than Porphyromonas gingivalis and Veillonella dispar, but considerably less than Fusobacterium nucleatum. The study has identified reliable growth conditions for culture of S. moorei, which were employed to show that S. moorei has the requisite biochemistry consistent with a potential role in halitosis. PMID:24487184

  19. Origins of sulfur compounds in the atmosphere of a zone of high productivity (Gulf of Guinea)

    SciTech Connect

    Delmas, R.; Servant, J.

    1982-12-20

    Recent observations have suggested substantial emission of sulfur compounds by oceanic water which could explain the presence of SO/sub 2/ and SO/sup +//sub 4/ in the air above these waters. The emission is thought to increase with the productivity of the oceanic zones. This point is discussed in relation to the Gulf of Guinea, a zone of high productivity. During the first two campaigns between Dakar, Abidjan, and the Gulf of Guinea SO/sup +//sub 4/ concentrations were measured in the air. Between Abidjan and the Gulf of Guinea the atmospheric SO= /sub 4/ concentrations decreased from 800 to 400 ng m/sup -3/. During the third campaign, between Abidjan and the South Equatorial Current (latitude 1/sup 0/S), the H/sub 2/S and SO/sub 2/ concentrations were measured. The mean H/sub 2/S concentration was 20 ng m/sup -3/, and that of SO/sub 2/ varied between 120 and under 50 ng m/sup -3/. The origins of SO/sub 2/ and SO/sup +//sub 4/ in the air of this area are discussed through the daily variations of the H/sub 2/S content of the air and a contribution from the forested zones of West Africa.

  20. The effect of an oral hygiene program on oral levels of volatile sulfur compounds (VSC).

    PubMed

    Seemann, R; Passek, G; Zimmer, S; Roulet, J F

    2001-01-01

    Volatile sulfur compounds (VSCs) produced by bacteria in niches of the oral cavity play a major role in the etiology of bad breath, and can be easily detected by a portable sulfide monitor (Halimeter). To investigate the effect of an oral hygiene program on VSC levels, Halimeter readings were taken from 55 healthy dental students during a course in oral hygiene training, including instruction on brushing, flossing and professional tooth cleaning. Ten students who received no oral hygiene training served as a negative control. The oral hygiene status was measured using the papillary bleeding index (PBI). PBI and VSC values did not show significant changes during the study period of 10 weeks in the control group. In the test group, PBI values significantly decreased compared to baseline and the control, indicating that the oral hygiene program had a benefit on the oral hygiene status. The VSC values also decreased significantly during the study period compared to baseline and the control. It was concluded that in a group of dental students, a thorough oral hygiene training program was capable of reducing the oral level of VSC Halimeter readings. PMID:11507918

  1. The relationship between oral malodor and volatile sulfur compound-producing bacteria.

    PubMed

    Krespi, Yosef P; Shrime, Mark G; Kacker, Ashutosh

    2006-11-01

    Halitosis can be a crippling social problem, and standard dental treatments and mouthwashes often provide only temporary relief. The mouth is home to hundreds of bacterial species that produce several fetid substances as a result of protein degradation. Volatile sulfur compound (VSC)-producing bacteria colonizing the lingual dorsum have recently been implicated in the generation of halitosis. Detection of VSCs, such as methylmercaptan and hydrogen sulfite, via organoleptic and objective methods, can aid in the identification of their source. Following comprehensive evaluation for possible causes, most halitosis in patients seen in an ENT practice can be localized to the tongue. We review methods of diagnosis and treatment of oral malodor from the overgrowth of proteolytic, anaerobic, gram-negative bacteria on the crevices of the lingual dorsum. Bacteriologic analysis of biofilm and scraped specimens obtained from the lingual dorsum and other oral sites, primarily gingival pockets and tonsillar crypts, can identify VSC-producing bacteria. Porphyromonas, Prevotella, Actinobacillus, and Fusobacterium species are the most common organisms identified. Halitosis is an oral phenomenon, with almost no cases originating distal to the tonsils. Halitosis arising from the lingual dorsum secondary to overpopulated VSC-producing bacteria can be successfully managed with a combination of mechanical cleansing using tongue brushes or scrapes and chemical solutions containing essential oils, zinc chloride, and cetylpyridinium chloride. PMID:17071291

  2. Multidimensional gas chromatography in combination with accurate mass, tandem mass spectrometry, and element-specific detection for identification of sulfur compounds in tobacco smoke.

    PubMed

    Ochiai, Nobuo; Mitsui, Kazuhisa; Sasamoto, Kikuo; Yoshimura, Yuta; David, Frank; Sandra, Pat

    2014-09-01

    A method is developed for identification of sulfur compounds in tobacco smoke extract. The method is based on large volume injection (LVI) of 10?L of tobacco smoke extract followed by selectable one-dimensional ((1)D) or two-dimensional ((2)D) gas chromatography (GC) coupled to a hybrid quadrupole time-of-flight mass spectrometer (Q-TOF-MS) using electron ionization (EI) and positive chemical ionization (PCI), with parallel sulfur chemiluminescence detection (SCD). In order to identify each individual sulfur compound, sequential heart-cuts of 28 sulfur fractions from (1)D GC to (2)D GC were performed with the three MS detection modes (SCD/EI-TOF-MS, SCD/PCI-TOF-MS, and SCD/PCI-Q-TOF-MS). Thirty sulfur compounds were positively identified by MS library search, linear retention indices (LRI), molecular mass determination using PCI accurate mass spectra, formula calculation using EI and PCI accurate mass spectra, and structure elucidation using collision activated dissociation (CAD) of the protonated molecule. Additionally, 11 molecular formulas were obtained for unknown sulfur compounds. The determined values of the identified and unknown sulfur compounds were in the range of 10-740ngmg total particulate matter (TPM) (RSD: 1.2-12%, n=3). PMID:25087743

  3. Thiosulfate and Sulfur Oxidation in Purple Sulfur Bacteria

    Microsoft Academic Search

    Frauke Grimm; Bettina Franz; Christiane Dahl

    In chemotrophic and phototrophic sulfur oxidizers that do not form sulfur deposits a periplasmic thiosulfate-oxidizing multienzyme\\u000a complex (Sox complex) has been described to be responsible for formation of sulfate from thiosulfate. In the anoxygenic phototrophic\\u000a sulfur bacterium Allochromatium vinosum intracellular sulfur globules are an obligate intermediate during the oxidation of thiosulfate to sulfate. Despite this fundamental\\u000a difference A. vinosum possesses

  4. Catalyst for the reduction of sulfur dioxide to elemental sulfur

    DOEpatents

    Jin, Yun (Peking, CN); Yu, Qiquan (Peking, CN); Chang, Shih-Ger (El Cerrito, CA)

    1996-01-01

    The inventive catalysts allow for the reduction of sulfur dioxide to elemental sulfur in smokestack scrubber environments. The catalysts have a very high sulfur yield of over 90% and space velocity of 10,000 h.sup.-1. They also have the capacity to convert waste gases generated during the initial conversion into elemental sulfur. The catalysts have inexpensive components, and are inexpensive to produce. The net impact of the invention is to make this technology practically available to industrial applications.

  5. Methods for removing malodorous sulfur compounds from pulp mill flue gases and the like by using green liquor

    SciTech Connect

    Farin, W.G.

    1984-02-14

    This is an improved method for removing malodorous sulfur compounds from flue gases generated in kraft or sodium sulfite pulping operations and the like by the absorption process using green liquor, an aqueous solution containing sodium sulfide and sodium carbonate. The malodorous gas compounds, including hydrogen sulfide, methyl mercaptan, and dimethyl sulfide are preferentially absorbed by the sodium sulfide forming sodium hydrosulfide and methanol. Any sulfur dioxide in the gas is absorbed and neutralized by sodium carbonate. In this method carbon dioxide absorption is minimized and the formation of sodium bicarbonate is limited. Sodium bicarbonate formation is minimized in order to avoid its reaction with sodium hydrosulfide which would then release undesirable hydrogen sulfide during absorption, as well as to forestall the need to increase chemical and lime kiln capacity requirements when the green liquor returned to the kraft recovery process contains excess amounts of sodium bicarbonate.

  6. Simultaneous measurement of volatile sulfur compounds using ascorbic acid for oxidant removal and gas chromatography-flame photometric detection.

    PubMed

    Inomata, Y; Matsunaga, K; Murai, Y; Osada, K; Iwasaka, Y

    1999-12-01

    A method for the simultaneous measurement of volatile sulfur compounds (COS, H2S, CS2, CH3SH, DMS) is established with preconcentration and GC-flame photometric detection (FPD). Prior to preconcentration of ambient air, it was necessary to remove SO2, water vapor and atmospheric oxidant. SO2 and water vapor were removed using a glass fiber filter and a cooled PTFE water trap loop, respectively. In order to remove atmospheric oxidant, the efficiency of an ascorbic acid scrubber was examined. It was found that an ascorbic acid scrubber enabled measurement of volatile sulfur compounds without adsorption and reaction loss. The detection limits for COS, H2S, CS2, CH3SH and DMS were 20, 34, 35, 263 and 44 pg of S, respectively. PMID:10630876

  7. Kinetics of Cisplatin and Its Monohydrated Complex with Sulfur-Containing Compounds Designed for Local Otoprotective Administration

    Microsoft Academic Search

    PERNILLA VIDEHULT; GORAN LAURELL; INGER WALLIN; HANS EHRSSON

    The anticancer drug cisplatin can cause permanent inner ear damage. We have determined the second-order degradation rate constant, kNu, of cisplatin and its more toxic monohydrated complex (MHC) in the presence of each of the sulfur-containing nucleophiles N-acetyl-L-cysteine, L-cysteine methyl ester, 1,3- dimethyl-2-thiourea, D-methionine, and thiosulfate, compounds that are under evaluation for local administration to prevent cisplatin-induced ototoxicity. MHC was

  8. ORIGINAL ARTICLE Sulfur oxidizers dominate carbon fixation

    E-print Network

    Hansell, Dennis

    ORIGINAL ARTICLE Sulfur oxidizers dominate carbon fixation at a biogeochemical hot spot in the dark clade of marine gamma-proteobacterial sulfur oxidizers (GSOs) are distributed throughout proteins for sulfur oxidation (adenosine phosphosulfate reductase, sox (sulfur oxidizing system

  9. Carbon nanostructures as catalytic support for chemiluminescence of sulfur compounds in a molecular emission cavity analysis system.

    PubMed

    Safavi, Afsaneh; Maleki, Norouz; Doroodmand, Mohammad Mahdi; Koleini, Mohammad Mehdi

    2009-06-30

    The effect of different substrates including stainless steel, activated carbon, single-walled carbon nanotubes (SWCNTs), multi-walled carbon nanotubes (MWCNTs), fullerenes (C60, C70, etc.) and SWCNTs doped with iron and palladium nanoparticles were compared for catalytic chemiluminescence reaction of sulfur compounds in a flame-containing cavity of molecular emission cavity analysis (MECA) system. Different forms of CNT substrates were fabricated using electric arc-discharge method. The blue emission of excited S2 was monitored using a CCD camera. The results demonstrate that, due to the high surface area, plenty of basal planes, high thermal conductivity, and high flexibility of the carbon nanostructure as appropriate support, carbon nanostructures play an important role in catalytic chemiluminescence emission of sulfur compounds in MECA. Moreover, the presence of metallic nanoparticles doped on carbon nanostructures enhances their catalytic effect. The results revealed that under similar conditions, SWCNTs/Pd doped nanoparticles, SWCNTs/Fe doped nanoparticles, SWCNTs, MWCNTs and fullerenes have the most catalytic effects on chemiluminescence of sulfur compounds, respectively. PMID:19463563

  10. ATP generation during reduced inorganic sulfur compound oxidation by Acidithiobacillus caldus is exclusively due to electron transport phosphorylation.

    PubMed

    Dopson, Mark; Lindström, E Börje; Hallberg, Kevin B

    2002-04-01

    The synthesis of adenosine 5-triphosphate (ATP) (increase in phosphorylation potential) during the oxidation of reduced inorganic sulfur compounds was studied in the moderately thermophilic acidophileAcidithiobacillus caldus (strain KU) (formerly Thiohacillus caldus). The phosphorylation potential increased during the oxidation of all reduced inorganic sulfur compounds tested compared with resting cells. The generation of ATP in whole cells was inhibited by the F0F1 ATPase inhibitor oligomycin, electron transport chain inhibitors, valinomycin and potassium ions. There was no increase in the phosphorylation potential, nor synthesis of ATP. in the absence of electron transport. An apparent lack of substrate-level phosphorylation was indicated by the lack of adenosine 5-phosphosulfate reductase in tetrathionate-grown At. caldus. Studies were also performed on the synthesis of ATP by membrane vesicles of At. caldus when presented with an artificial proton gradient. Complete inhibition of ATP synthesis in these vesicles occurred when they were loaded with N,N-dicyclohexylcarbodiimide (DCCD), but not when they were loaded with oligomycin, vanadate or electron transport chain inhibitors. The data presented here suggest that during the oxidation of reduced inorganic sulfur compounds by At. caldus, all ATP is synthesized by oxidative phosphorylation via a membrane-bound F0F1 ATPase driven by a proton gradient. PMID:12013432

  11. 8, 93479404, 2008 Sulfur isotope

    E-print Network

    Paris-Sud XI, Université de

    ACPD 8, 9347­9404, 2008 Sulfur isotope analyses of individual aerosol particles B. Winterholler et the Creative Commons Attribution 3.0 License. Atmospheric Chemistry and Physics Discussions Sulfur isotope by Copernicus Publications on behalf of the European Geosciences Union. 9347 #12;ACPD 8, 9347­9404, 2008 Sulfur

  12. Sulfur in basaltic magmas

    Microsoft Academic Search

    Paul Wallace; Ian S. E. Carmichael

    1992-01-01

    The concentration of S in basaltic magmas at 1 atm pressure is strongly dependent on temperature, the fugacities of oxygen ( f O 2 ) and sulfur ( f S 2 ), and bulk composition. Microprobe analyses of total S in rapidly quenched, submarine basalt glasses, used in conjunction with wet chemical analyses of Fe 2 O 3 \\/ FeO

  13. Sodium sulfur battery seal

    DOEpatents

    Topouzian, Armenag (Birmingham, MI)

    1980-01-01

    This invention is directed to a seal for a sodium sulfur battery in which a flexible diaphragm sealing elements respectively engage opposite sides of a ceramic component of the battery which separates an anode compartment from a cathode compartment of the battery.

  14. COAL SULFUR MEASUREMENTS

    EPA Science Inventory

    The report describes a new technique for sulfur forms analysis based on low-temperature oxygen plasma ashing. The technique involves analyzing the low-temperature plasma ash by modified ASTM techniques after selectively removing the organic material. The procedure has been tested...

  15. Biogenic sulfur source strengths

    Microsoft Academic Search

    Donald F. Adams; Sherry O. Farwell; Elmer. Robinson; Merrill R. Pack; W. Lee. Bamesberger

    1981-01-01

    Conclusions are presented from a 4-yr field measurement study of biogenic sulfur gas emissions from soils, and some water and vegetated surfaces, at 35 locales in the eastern and southeastern United States. More than one soil order was examined whenever possible to increase the data base obtained from the 11 major soil orders comprising the study area. Data analysis and

  16. Sulfur Dioxide Pollution Monitor.

    ERIC Educational Resources Information Center

    National Bureau of Standards (DOC), Washington, DC.

    The sulfur dioxide pollution monitor described in this document is a government-owed invention that is available for licensing. The background of the invention is outlined, and drawings of the monitor together with a detailed description of its function are provided. A sample stream of air, smokestack gas or the like is flowed through a…

  17. Allyl isothiocyanate from mustard seed is effective in reducing the levels of volatile sulfur compounds responsible for intrinsic oral malodor.

    PubMed

    Tian, Minmin; Hanley, A Bryan; Dodds, Michael W J

    2013-06-01

    Oral malodor is a major social and psychological issue that affects general populations. Volatile sulfur compounds (VSCs), particularly hydrogen sulfide (H?S) and methyl mercaptan (CH?SH), are responsible for most oral malodor. The objectives for this study were to determine whether allyl isothiocyanate (AITC) at an organoleptically acceptable level can eliminate VSCs containing a free thiol moiety and further to elucidate the mechanism of action and reaction kinetics. The study revealed that gas chromatograph with a sulfur detector demonstrated a good linearity, high accuracy and sensitivity on analysis of VSCs. Zinc salts eliminate the headspace level of H?S but not CH?SH. AITC eliminates both H?S and CH?SH via a nucleophilic addition reaction. In addition, a chemical structure-activity relationship study revealed that the presence of unsaturated group on the side chain of the isothiocyanate accelerates the elimination of VSCs. PMID:23470258

  18. Effects of stress hormones on the production of volatile sulfur compounds by periodontopathogenic bacteria.

    PubMed

    Calil, Caroline Morini; Oliveira, Gisele Mattos; Cogo, Karina; Pereira, Antonio Carlos; Marcondes, Fernanda Klein; Groppo, Francisco Carlos

    2014-01-01

    Little is known about the effects of stress hormones on the etiologic agents of halitosis. Thus, the aim of this study was to evaluate in vitro the effects of adrenaline (ADR), noradrenaline (NA) and cortisol (CORT) on bacteria that produce volatile sulfur compounds (VSC), the major gases responsible for bad breath. Cultures of Fusobacterium nucleatum (Fn), Porphyromonas endodontalis (Pe), Prevotella intermedia (Pi) and Porphyromonas gingivalis (Pg) were exposed to 50 µM ADR, NA and CORT or equivalent volumes of sterile water as controls for 12 and 24 h. Growth was evaluated based on absorbance at 660 nm. Portable gas chromatography was used to measure VSC concentrations. Kruskal-Wallis and the Dunn post-hoc test were used to compare the groups. For Fn, ADR, NA and CORT significantly reduced bacterial growth after 12 h and 24 h (p<0.05). All the substances tested increased hydrogen sulfide (H2S) production (p<0.05). For Pe, all the substances tested reduced bacterial development after 24 h (p<0.05), and NA significantly increased the H2S concentration after 12 h (p<0.05). In the Pg and Pi cultures, no effects on bacterial growth were observed (p>0.05). In the Pi cultures, ADR, NA and CORT increased H2S (p<0.05). Catecholamines and cortisol can interfere with growth and H2S production of sub-gingival species in vitro. This process appears to be complex and supports the association between stress and the production of VSC. PMID:24918364

  19. Reduction of bacterial volatile sulfur compound production by licoricidin and licorisoflavan A from licorice.

    PubMed

    Tanabe, Shin-ichi; Desjardins, Jacynthe; Bergeron, Chantal; Gafner, Stefan; Villinski, Jacquelyn R; Grenier, Daniel

    2012-03-01

    Halitosis affects a large proportion of the population and is, in most cases, caused by the production of volatile sulfur compounds (VSCs), particularly methyl mercaptan and hydrogen sulfide, by specific bacterial species colonizing the oral cavity. In this study, a supercritical extract of Chinese licorice (Glycyrrhiza uralensis), and its major isoflavans, licoricidin and licorisoflavan A, were investigated for their effect on growth, VSC production and protease activity of Porphyromonas gingivalis, Prevotella intermedia and Solobacterium moorei, which have been associated with halitosis. The effects of licorice extract, licoricidin, and licorisoflavan A on VSC production in a saliva model were also tested. We first showed that licoricidin and licorisoflavan A, and to a lesser extent the licorice extract, were effective in inhibiting the growth of all three bacterial species, with minimal inhibitory concentrations in the range of 2-80 µg ml(-1). The licorice extract and the two isolates licoricidin and licorisoflavan A, were able to dose-dependently reduce VSC production by P. gingivalis, Prev. intermedia, and S. moorei as well as by a human saliva model. Although the extract and isolates did not inhibit the proteolytic activity of bacteria, they blocked the conversion of cysteine into hydrogen sulfide by Prev. intermedia. Lastly, the deodorizing effects of the licorice extract, licoricidin, and licorisoflavan A were demonstrated, as they can neutralize P. gingivalis-derived VSCs. Licorisoflavan A (10 µg ml(-1)) was found to be the most effective by reducing VSC levels by 50%. Within the limitations of this study, it can be concluded that a licorice supercritical extract and its major isoflavans (licoricidin and licorisoflavan A) represent natural ingredients with a potential for reducing bacterial VSC production and therefore for controlling halitosis. PMID:22368239

  20. Use of Oral Chroma™ in the assessment of volatile sulfur compounds in patients with fixed protheses.

    PubMed

    Sinjari, B; Murmura, G; Caputi, S; Ricci, L; Varvara, G; Scarano, A

    2013-01-01

    Prosthetic rehabilitation improves the patient's quality of life and oral health. The purpose of the present study was to assess the production of volatile sulfur compounds (VSCs) using Oral Chroma? in patients wearing provisional and permanent fixed prosthesis, who were treated or not, with supportive non-surgical periodontal therapy. A total of 10 healthy patients not affected by periodontal disease and who needed the restoration of at least two edentulous single sites were included in the present study. Registrations of VSCs were carried out with a Gas Chromatograph OralChroma™ (Oral Chroma™, Abimedical, Abilit Corp., Osaka, Japan) one month after placement of the provisional restoration (group 1) and one month after placement of the final restoration (group 3). After each measurement, professional oral hygiene was carried out both on patients with provisional (group 2) and permanent prostheses (group 4) and VSC values were registered. The results showed that there were no statistical significant differences in the VSC quantity between groups with temporary or permanent prostheses. Meanwhile, statistically significant differences were found in VCS values between groups before and after the professional health care session (p less than 0.05). Also it was observed that dimethyl sulphide (CH3)2S was present in all the study groups. The present preliminary study suggests that OralChroma™ produce a comprehensive assessment of VSC in the clinical diagnosis of halitosis and that professional oral hygiene seems to influence VSC production. However, further clinical long-term studies with a larger sample size are necessary for a better understanding of halitosis manifestation in patients wearing provisional and permanent fixed prosthesis. PMID:24067465

  1. Global distribution of sulfur compounds in the troposphere estimated in a height/latitude transport model

    SciTech Connect

    Rodhe, H.; Isaksen, I.

    1980-01-01

    A global two-dimensional time-dependent model has been used to estimate the tropospheric distributions of sulfur compounds resulting from natural emissions of H/sub 2/S or DMS and from man-made emissions of SO/sub 2/. Comparisons of observations of H/sub 2/S, DMS, SO/sub 2/, and SO/sub 4//sup 2 -/ remote areas with the model estimates indicate that the global flux of H/sub 2/S and DMS, taken together, amounts to at most a few tens of tg s/yr. The present man-made emissions of SO/sub 2/ (about 80 tg s/yr) can account for a dominant part of the SO/sub 2/ and SO/sub 4//sup 2 -/ observed in the lower troposphere of the northern hemisphere. On the other hand, neither natural emissions of H/sub 2/S and DMS at the surface nor man-made emissions of SO/sub 2/ seem to be able to explain the relatively high values of SO/sub 2/ observed in the middle and upper troposphere in both hemispheres. Our calculations indicate that a relatively long-lived precursor must be involved as a source for this SO/sub 2/. The amount of SO/sub 2/ produced by the oxidation of CS/sub 2/ and OCS does not seem sufficiently high. Average residence times in the atmosphere for H/sub 2/S, SO/sub 2/, and SO/sub 4//sup 2 -/ have been estimated to about 1, 1.5, and 5 days, respectively. If only higher portions of the troposphere are considered, the residence times increase considerably.

  2. The loss patterns of reduced sulfur compounds in contact with different tubing materials.

    PubMed

    Kim, Ki-Hyun; Ahn, Ji-Won; Choi, Ye-Jin; Nguyen, Hang T

    2006-11-01

    To collect or transfer samples of airborne pollutants, tubings made of various materials are used. To analyze the reactive loss patterns of reduced sulfur compounds (RSC) in the use of tubing fittings, a series of laboratory experiments were conducted so that the concentration changes were induced by the physical contact between gas samples and tubing walls. For the purpose of this study, a total of five tubing materials were investigated in reference to silcosteel (S1) tubing: stainless steel (S2), silicone (S3), PTFE Teflon (T1), tygon (T2), and copper (C). This comparative experiment was made using gaseous standards containing equimolar concentrations of four RSCs (H(2)S, CH(3)SH, DMS, and DMDS). The loss patterns of RSC were then evaluated and compared in terms of their calibration slope values across different tubing materials. The results of this comparative analysis indicated that except for a few cases, a fairly good compatibility was seen consistently among different tubing types and different RSCs. The results generally showed that the magnitude of calibration slope values obtained from different tubing materials tend to increase with an increase in RSC molecular weights. If the results are compared between different tubing materials, a highly contrasting pattern was evident. For instance, C tubing shows significant losses of light RSCs (H(2)S and CH(3)SH), while S3 tubing experiences the large losses of DMS and DMDS. A line of evidence found in this study thus suggests that most tubing types have their unique loss mechanism for RSCs, when they contact RSCs in sample gas stream passing through the tubing walls. PMID:16875695

  3. Transporters in plant sulfur metabolism.

    PubMed

    Gigolashvili, Tamara; Kopriva, Stanislav

    2014-01-01

    Sulfur is an essential nutrient, necessary for synthesis of many metabolites. The uptake of sulfate, primary and secondary assimilation, the biosynthesis, storage, and final utilization of sulfur (S) containing compounds requires a lot of movement between organs, cells, and organelles. Efficient transport systems of S-containing compounds across the internal barriers or the plasma membrane and organellar membranes are therefore required. Here, we review a current state of knowledge of the transport of a range of S-containing metabolites within and between the cells as well as of their long distance transport. An improved understanding of mechanisms and regulation of transport will facilitate successful engineering of the respective pathways, to improve the plant yield, biotic interaction and nutritional properties of crops. PMID:25250037

  4. Transporters in plant sulfur metabolism

    PubMed Central

    Gigolashvili, Tamara; Kopriva, Stanislav

    2014-01-01

    Sulfur is an essential nutrient, necessary for synthesis of many metabolites. The uptake of sulfate, primary and secondary assimilation, the biosynthesis, storage, and final utilization of sulfur (S) containing compounds requires a lot of movement between organs, cells, and organelles. Efficient transport systems of S-containing compounds across the internal barriers or the plasma membrane and organellar membranes are therefore required. Here, we review a current state of knowledge of the transport of a range of S-containing metabolites within and between the cells as well as of their long distance transport. An improved understanding of mechanisms and regulation of transport will facilitate successful engineering of the respective pathways, to improve the plant yield, biotic interaction and nutritional properties of crops. PMID:25250037

  5. Immunological consequence of sulfur mustard exposure

    Microsoft Academic Search

    Zuhaiar M Hassan; Massoumeh Ebtekar

    2002-01-01

    Global reports indicate that chemical weapons still impose a serious threat to world security and health. Sulfur mustard is a chemical compound with devastating short and long-term effect on human health.

  6. Genomic and Evolutionary Perspectives on Sulfur Metabolism in Green Sulfur Bacteria

    Microsoft Academic Search

    Niels-Ulrik Frigaard; Donald A. Bryant

    Green sulfur bacteria (GSB) are anaerobic photoautotrophs that oxidize sulfide, elemental sulfur, thiosulfate, ferrous iron,\\u000a and hydrogen for growth. We present here an analysis of the distribution and evolution of enzymes involved in oxidation of\\u000a sulfur compounds in GSB based on genome sequence data from 12 strains. Sulfide:quinone reductase (SQR) is found in all strains.\\u000a Chlorobium ferrooxidans, which cannot grow

  7. Acidithiobacillus caldus Sulfur Oxidation Model Based on Transcriptome Analysis between the Wild Type and Sulfur Oxygenase Reductase Defective Mutant

    PubMed Central

    Chen, Linxu; Ren, Yilin; Lin, Jianqun; Liu, Xiangmei; Pang, Xin; Lin, Jianqiang

    2012-01-01

    Background Acidithiobacillus caldus (A. caldus) is widely used in bio-leaching. It gains energy and electrons from oxidation of elemental sulfur and reduced inorganic sulfur compounds (RISCs) for carbon dioxide fixation and growth. Genomic analyses suggest that its sulfur oxidation system involves a truncated sulfur oxidation (Sox) system (omitting SoxCD), non-Sox sulfur oxidation system similar to the sulfur oxidation in A. ferrooxidans, and sulfur oxygenase reductase (SOR). The complexity of the sulfur oxidation system of A. caldus generates a big obstacle on the research of its sulfur oxidation mechanism. However, the development of genetic manipulation method for A. caldus in recent years provides powerful tools for constructing genetic mutants to study the sulfur oxidation system. Results An A. caldus mutant lacking the sulfur oxygenase reductase gene (sor) was created and its growth abilities were measured in media using elemental sulfur (S0) and tetrathionate (K2S4O6) as the substrates, respectively. Then, comparative transcriptome analysis (microarrays and real-time quantitative PCR) of the wild type and the ?sor mutant in S0 and K2S4O6 media were employed to detect the differentially expressed genes involved in sulfur oxidation. SOR was concluded to oxidize the cytoplasmic elemental sulfur, but could not couple the sulfur oxidation with the electron transfer chain or substrate-level phosphorylation. Other elemental sulfur oxidation pathways including sulfur diooxygenase (SDO) and heterodisulfide reductase (HDR), the truncated Sox pathway, and the S4I pathway for hydrolysis of tetrathionate and oxidation of thiosulfate in A. caldus are proposed according to expression patterns of sulfur oxidation genes and growth abilities of the wild type and the mutant in different substrates media. Conclusion An integrated sulfur oxidation model with various sulfur oxidation pathways of A. caldus is proposed and the features of this model are summarized. PMID:22984393

  8. Sulfur in gasoline

    SciTech Connect

    Pearce, J.R.; Keyworth, D.; Desai, P.H. [Akzo Chemicals Inc., Pasadena, TX (United States)

    1993-12-31

    The international refiner is presently being squeezed by narrow refining margins and ever increasing demands for improved product quality. One high visibility aspect of this quality is the amount of sulfur allowed in motor gasoline under present and future regulations. This limit alone will call for fundamental changes in refining strategy, as well as require large capital investments. This paper will review the interaction of hydrotreating and FCC technologies, with the goal of describing that will be necessary to economically meet the gasoline sulfur limits in the coming years. The interaction with other upstream and downstream refinery operations will be considered within the boarder scope of total refinery products needed in the decade of reformulated fuels.

  9. Effects of heteroatom substitution in conjugated heterocyclic compounds on photovoltaic performance: from sulfur to tellurium.

    PubMed

    Park, Y S; Kale, T S; Nam, C-Y; Choi, D; Grubbs, R B

    2014-07-28

    We report a general strategy for fine-tuning the bandgap of donor-acceptor-donor based organic molecules by modulating the electron-donating ability of the donor moiety by changing the benzochalcogenophene donor groups from benzothiophenes to benzoselenophenes to benzotellurophenes. These molecules show red-shifts in absorption and external quantum efficiency maxima from sulfur to selenium to tellurium. In bulk heterojunction solar cell devices, the benzoselenophene derivative shows a power conversion efficiency as high as 5.8% with PC61BM as the electron acceptor. PMID:24842497

  10. Sulfur mobility in peat

    Microsoft Academic Search

    Martin Novák; Marie Adamová; R. Kelman Wieder; Simon H. Bottrell

    2005-01-01

    Lead-210 chronologies, vertical S concentration gradients and ?34S values are presented for 5 Sphagnum-dominated peat bogs located in Central Europe (Rybarenska slat and Ocean Bog; Czech Republic) and the British Isles (Thorne Moors, England; Connemara, Ireland; and Mull, Scotland). Sulfur concentrations were measured in three 40-cm deep peat cores per site, sectioned into 2-cm segments. The coefficient of variation in

  11. Acidophilic sulfur disproportionation

    NASA Astrophysics Data System (ADS)

    Hardisty, Dalton S.; Olyphant, Greg A.; Bell, Jonathan B.; Johnson, Adam P.; Pratt, Lisa M.

    2013-07-01

    Bacterial disproportionation of elemental sulfur (S0) is a well-studied metabolism and is not previously reported to occur at pH values less than 4.5. In this study, a sediment core from an abandoned-coal-mine-waste deposit in Southwest Indiana revealed sulfur isotope fractionations between S0 and pyrite (?34Ses-py) of up to -35‰, inferred to indicate intense recycling of S0 via bacterial disproportionation and sulfide oxidation. Additionally, the chemistry of seasonally collected pore-water profiles were found to vary, with pore-water pH ranging from 2.2 to 3.8 and observed seasonal redox shifts expressed as abrupt transitions from Fe(III) to Fe(II) dominated conditions, often controlled by fluctuating water table depths. S0 is a common product during the oxidation of pyrite, a process known to generate acidic waters during weathering and production of acid mine drainage. The H2S product of S0 disproportionation, fractionated by up to -8.6‰, is rapidly oxidized to S0 near redox gradients via reaction with Fe(III) allowing for the accumulation of isotopically light S0 that can then become subject to further sulfur disproportionation. A mass-balance model for S0 incorporating pyrite oxidation, S0 disproportionation, and S0 oxidation readily explains the range of observed ?34Ses-py and emphasizes the necessity of seasonally varying pyrite weathering and metabolic rates, as indicated by the pore water chemistry. The findings of this research suggest that S0 disproportionation is potentially a common microbial process at a pH < 4.5 and can create large sulfur isotope fractionations, even in the absence of sulfate reduction.

  12. Sulfur dichloride, SCl2

    NSDL National Science Digital Library

    This month's molecule is sulfur dichloride, SCl2. This and other small inorganic molecules are discussed in the article by Matta and Gillespie. They describe electron density in molecules and how to analyze it to obtain information about molecular bonding and structure. Different depictions of electron density in SCl2 and other small molecules emphasize different aspects of their electron density and of the structures of the molecules.

  13. Sulfur plumes off Namibia

    NASA Technical Reports Server (NTRS)

    2002-01-01

    Sulfur plumes rising up from the bottom of the ocean floor produce colorful swirls in the waters off the coast of Namibia in southern Africa. The plumes come from the breakdown of marine plant matter by anaerobic bacteria that do not need oxygen to live. This image was acquired by the Moderate Resolution Imaging Spectroradiometer (MODIS) on the Terra satellite on April 24, 2002 Credit: Jacques Descloitres, MODIS Land Rapid Response Team, NASA/GSFC

  14. Method for reducing the sulfur content of a sulfur-containing hydrocarbon stream

    DOEpatents

    Mahajan, Devinder

    2004-12-28

    The sulfur content of a liquid hydrocarbon stream is reduced under mild conditions by contracting a sulfur-containing liquid hydrocarbon stream with transition metal particles containing the transition metal in a zero oxidation state under conditions sufficient to provide a hydrocarbon product having a reduced sulfur content and metal sulfide particles. The transition metal particles can be produced in situ by adding a transition metal precursor, e.g., a transition metal carbonyl compound, to the sulfur-containing liquid feed stream and sonicating the feed steam/transition metal precursor combination under conditions sufficient to produce the transition metal particles.

  15. Sulfur Metabolism in Plastids Elizabeth A.H. Pilon-Smits

    E-print Network

    Chapter 19 Sulfur Metabolism in Plastids Elizabeth A.H. Pilon-Smits and Marinus Pilon Biology ................................................................................................................. 387 II. Sulfur Compounds and Their Properties ......................................................................................................................... 398 Summary Sulfur is an essential element for plant primary metabolism as a structural component

  16. Factors controlling fluxes of volatile sulfur compounds in Sphagnum peatlands. Ph.D. Thesis

    NASA Technical Reports Server (NTRS)

    Demello, William Zamboni

    1992-01-01

    Exchange of DMS and OCS between the surface of Sphagnum peatlands and the atmosphere were measured with dynamic (S-free sweep air) and static enclosures. DMS emission rates determined by both methods were comparable. The dynamic method provided positive OCS flux rates (emission) for measurements performed at sites containing Sphagnum. Conversely, data from the static method indicated that OCS was consumed from the atmosphere. Short and long-term impacts of increased S deposition on fluxes of volatile S compounds (VSC's) from Sphagnum peatlands were investigated in a poor fen (Mire 239) at the Experimental Lakes Area, Ontario, Canada. Additional experiments were conducted in a poor fen (Sallie's Fen in Barrington, NH, USA). At Mire 239, emissions of VSC's were monitored, before and after acidification, at control and experimental sections within two major physiographic areas of the mire (oligotrophic and minerotrophic). DMS was the predominant VSC released from Mire 239 and varied largely with time and space. Sulfur addition did not affect DMS emissions in a period of hours to a few days. DMS emissions in the experimental oligotrophic area of the mire was approximately 3-fold greater than in the control oligotrophic area, and approximately 10-fold greater than in the minerotrophic zones. These differences could be due to a combination of differences in types of vegetation, nutritional status, and S input. At Sallie's Fen, DMS fluxes were not significantly affected by sulfate amendments, while DMS and MSH concentrations increased greatly with time in the top 10 cm of the peat column. The major environmental factors controlling fluxes of DMS in a Sphagnum-dominated peatland were investigated in Sallie's Fen, NH. DMS emissions from the surface of the peatland varied greatly over 24 hours and seasonally. Temperature seemed to be the major environmental factor controlling these variabilities. Concentrations of dissolved VSC's varied with time and space throughout the fen. Dissolved DMS, MSH, and OCS in the surface of the water table were supersaturated with respect to their concentrations in the atmosphere. Sphagnum mosses did not appear to be a direct source of VSC's, however they increase transport of DMS from the peat surface to the atmosphere.

  17. Understanding Sulfur Systematics in Large Igneous Provinces Using Sulfur Isotopes

    NASA Astrophysics Data System (ADS)

    Novikova, S.; Edmonds, M.; Turchyn, A. V.; Maclennan, J.; Svensen, H.; Frost, D. J.; Yallup, C.

    2013-12-01

    The eruption of the Siberian Traps coincided with perhaps the greatest environmental catastrophe in Earth's history, at the Permo-Triassic boundary. The source and magnitude of the volatile emissions, including sulfur, associated with the eruption remain poorly understood yet were critical in forcing environmental change. Two of the primary questions are how much sulfur gases were emitted during the eruptions and from where they were sourced. Primary melts carry dissolved sulfur from the mantle. Magmas ponding in sills and ascending through dykes may also assimilate sulfur from country rocks, as well as heat the country rocks and generate fluids through contact metamorphism. If the magmas interacted thermally, for prolonged periods, with sulfur-rich country rocks then it is probable that the sulfur budget of these eruptions might have been augmented considerably. This is exactly what we have shown recently for a basaltic sill emplaced in oil shale that fed eruptions of the British Tertiary Province, where surrounding sediments showed extensive desulfurization (Yallup et al. Geoch. Cosmochim. Acta, online, 2013). In the current study sulfur isotopes and trace element abundances are used to discriminate sulfur sources and to model magmatic processes for a suite of Siberian Traps sill and lava samples. Our bulk rock and pyrite geochemical analyses illustrate clearly their high abundance of 34S over 32S. The high 34S/32S has been noted previously and linked to assimilation of sulfur from sediments but may alternatively be inherited from the mantle plume source. With the aim of investigating the sulfur isotopic signature in the melt prior to devolatilization, we use secondary ion mass spectrometry (SIMS), for which a specific set of glass standards was synthesised. In order to understand how sulfur isotopes fractionate during degassing we have also conducted a parallel study of well-characterized tephras from Kilauea Volcano, where sulfur degassing behavior is well known.

  18. Influence of Sulfur for Oxygen Substitution in the Solvolytic Reactions of Chloroformate Esters and Related Compounds

    PubMed Central

    D’Souza, Malcolm J.; Kevill, Dennis N.

    2014-01-01

    The replacement of oxygen within a chloroformate ester (ROCOCl) by sulfur can lead to a chlorothioformate (RSCOCl), a chlorothionoformate (ROCSCl), or a chlorodithioformate (RSCSCl). Phenyl chloroformate (PhOCOCl) reacts over the full range of solvents usually included in Grunwald-Winstein equation studies of solvolysis by an addition-elimination (A-E) pathway. At the other extreme, phenyl chlorodithioformate (PhSCSCl) reacts across the range by an ionization pathway. The phenyl chlorothioformate (PhSCOCl) and phenyl chlorothionoformate (PhOCSCl) react at remarkably similar rates in a given solvent and there is a dichotomy of behavior with the A-E pathway favored in solvents such as ethanol-water and the ionization mechanism favored in aqueous solvents rich in fluoroalcohol. Alkyl esters behave similarly but with increased tendency to ionization as the alkyl group goes from 1° to 2° to 3°. N,N-Disubstituted carbamoyl halides favor the ionization pathway as do also the considerably faster reacting thiocarbamoyl chlorides. The tendency towards ionization increases as, within the three contributing structures of the resonance hybrid for the formed cation, the atoms carrying positive charge (other than the central carbon) change from oxygen to sulfur to nitrogen, consistent with the relative stabilities of species with positive charge on these atoms. PMID:25310653

  19. Sulfurized limonite as material for fast decomposition of organic compounds by heterogeneous Fenton reaction.

    PubMed

    Toda, Kei; Tanaka, Toshinori; Tsuda, Yutaka; Ban, Masahiro; Koveke, Edwin P; Koinuma, Michio; Ohira, Shin-Ichi

    2014-08-15

    Rapid decomposition of wastewater contaminants using sulfurized limonite (S-limonite) was investigated. Limonite is used for desulfurization of biogases, and S-limonite is obtained from desulfurization plants as solid waste. In this work, the profitable use of S-limonite in water treatment was examined. The divalent Fe in S-limonite was expected to produce OH radicals, as Fe(2+) ions and limonite thermally treated with H2 do. Methylene blue was used for batch-wise monitoring of the decomposition performance. The decomposition rate was fast and the methylene blue solution color disappeared in only 10s when a small amount of H2O2 was added (1mM in the sample solution) in the presence of S-limonite. The OH radicals were formed by a heterogeneous reaction on the S-limonite surface and Fenton reaction with dissolved Fe(2+). The decomposition of pentachlorophenol was also examined; it was successfully decomposed in batch-wise tests. The surfaces of limonite before sulfurization, S-limonite, and S-limonite after use for water treatment were performed using scanning electron microscopy and X-ray photoelectron spectroscopy. The results show that S-limonite reverted to limonite after being used for water treatment. PMID:24997258

  20. Facilitated and selective oxidation of thiophenic sulfur compounds using MoOx/Al?O?-H?O? system under ultrasonic irradiation.

    PubMed

    Akbari, Azam; Omidkhah, Mohammadreza; Towfighi Darian, Jafar

    2015-03-01

    Oxidative desulfurization of thiophenic sulfur compounds of benzothiophene (BT), dibenzothiophene (DBT) and 4,6-dimethyl dibenzothiophene (4,6-DMDBT) with MoOx/Al?O? catalyst and H?O? oxidant has been facilitated and more selective under ultrasonic irradiation. The catalyst with the optimum 10% of Mo loading consisted of isolated tetrahedral molybdenum oxide species based on FTIR analysis. The increase of Mo loading to 15% and 20% caused to generation of polymolybdate and MoO? crystals which decreased desulfurization activity. Sonication enhanced the apparent reaction rate constants in oxidation of all three sulfur compounds. An increase in the Arrhenius factor (A0), which is the total number of collisions per second, could explain the acceleration in the rate constants by sonication. The apparent activated energy (Ea) of BT oxidation was reduced from 96.6 to 75.3 kJ/mol by using ultrasound. This indicated that ultrasound had also a chemical effect, like a catalytic influence, in the acceleration of BT removal. DBT oxidation was reduced when investigated in the presence of tetralin, naphthalene and 2-methyl naphthalene as the model aromatic compounds of actual light oils. A higher selectivity toward DBT elimination in the presence of aromatics was obtained by sonication when compared with the silent treatment. Ultrasound cleaned the catalyst surface from adsorbed aromatics. On the basis of the obtained results, a mechanistic proposal for this desulfurization was explained. Oxidation was performed by nucleophilic attack of sulfur atom to the molybdenum peroxide species of tetrahedral molybdates, which was more advanced by sonication. PMID:25258211

  1. Catalyst for the reduction of sulfur dioxide to elemental sulfur

    DOEpatents

    Jin, Y.; Yu, Q.; Chang, S.G.

    1996-02-27

    The inventive catalysts allow for the reduction of sulfur dioxide to elemental sulfur in smokestack scrubber environments. The catalysts have a very high sulfur yield of over 90% and space velocity of 10,000 h{sup {minus}1}. They also have the capacity to convert waste gases generated during the initial conversion into elemental sulfur. The catalysts have inexpensive components, and are inexpensive to produce. The net impact of the invention is to make this technology practically available to industrial applications. 21 figs.

  2. Argonne Electrochemical Technology Program Sulfur removal from reformate

    E-print Network

    Argonne Electrochemical Technology Program Sulfur removal from reformate Xiaoping Wang, Theodore, and diesel. · These fuels contain sulfur compounds that can poison catalysts in the fuel processor and fuel Electrochemical Technology Program Objective: develop a sulfur removal process for use in on-board fuel processor

  3. Relationship between corrosion and the biological sulfur cycle: A review

    SciTech Connect

    Little, B.J.; Ray, R.I.; Pope, R.K.

    2000-04-01

    Sulfur and sulfur compounds can produce pitting, crevice corrosion, dealloying, stress corrosion cracking, and stress-oriented hydrogen-induced cracking of susceptible metals and alloys. Even though the metabolic by-products of the biological sulfur cycle are extremely corrosive, there are no correlations between numbers and types of sulfur-related organisms and the probability or rate of corrosion, Determination of specific mechanisms for corrosion caused by microbiologically mediated oxidation and reduction of sulfur and sulfur compounds is complicated by the variety of potential metabolic-energy sources and by-products; the coexistence of reduced and oxidized sulfur species; competing reactions with inorganic and organic compounds; and the versatility and adaptability of microorganisms in biofilms. The microbial ecology of sulfur-rich environments is poorly understood because of the association of aerobes and anaerobes and the mutualism or succession of heterotrophs to autotrophs. The physical scale over which the sulfur cycle influences corrosion varies with the environment. The complete sulfur cycle of oxidation and reduction reactions can take place in macroenvironments, including sewers and polluted harbors, or within the microenvironment of biofilms. In this review, reactions of sulfur and sulfur compounds resulting in corrosion were discussed in the context of environmental processes important to corrosion.

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

    SciTech Connect

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

    1990-08-01

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

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

    SciTech Connect

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

    1990-08-01

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

  6. Reduced and Oxidized Sulfur Compounds Detected by Evolved Gas Analyses of Materials from Yellowknife Bay, Gale Crater, Mars

    NASA Technical Reports Server (NTRS)

    McAdam, A. C.; Franz, H. B.; Archer, P. D., Jr.; Sutter, B.; Eigenbrode, J. L.; Freissinet, C.; Atreya, S. K.; Bish, D. L.; Blake, D. F.; Brunner, A.; Mahaffy, P. R.; Ming, D. W.; Morris, R. V.; Navarro-Gonzalez, R.; Rampe, E. B.; Steele, A.; Wray, J. J.

    2014-01-01

    Sulfate minerals have been directly detected or strongly inferred from several Mars datasets and indicate that aqueous alteration of martian surface materials has occurred. Indications of reduced sulfur phases (e.g., sulfides) from orbital and in situ investigations of martian materials have been fewer in number, but these phases are observed in martian meteorites and are likely because they are common minor phases in basaltic rocks. Here we discuss potential sources for the S-bearing compounds detected by the Mars Science Laboratory (MSL) Sample Analysis at Mars (SAM) instrument’s evolved gas analysis (EGA) experiments.

  7. Elemental sulfur in the gills of three species of clams containing chemoautotrophic symbiotic bacteria: a possible inorganic energy storage compound

    Microsoft Academic Search

    R. D. Vetter

    1985-01-01

    Sulfur content and fine structure were studied for tissues of three species of clams, Lucinoma annulata, Calyptogena elongata and Lucina floridana, which inhabit sulfide-rich environments and whose gills harbor symbiotic sulfur bacteria. Lucinoma annulata and C. elongata were dredged from the Santa Barbara basin, California, USA, at a depth of 480 to 490 m, and Lucina floridana were dug from

  8. 40 CFR 50.17 - National primary ambient air quality standards for sulfur oxides (sulfur dioxide).

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...National primary ambient air quality standards for sulfur oxides (sulfur dioxide). 50.17 Section 50.17 Protection...National primary ambient air quality standards for sulfur oxides (sulfur dioxide). (a) The level...

  9. 40 CFR 50.17 - National primary ambient air quality standards for sulfur oxides (sulfur dioxide).

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...National primary ambient air quality standards for sulfur oxides (sulfur dioxide). 50.17 Section 50.17 Protection...National primary ambient air quality standards for sulfur oxides (sulfur dioxide). (a) The level...

  10. 40 CFR 50.17 - National primary ambient air quality standards for sulfur oxides (sulfur dioxide).

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...National primary ambient air quality standards for sulfur oxides (sulfur dioxide). 50.17 Section 50.17 Protection...National primary ambient air quality standards for sulfur oxides (sulfur dioxide). (a) The level...

  11. 40 CFR 50.17 - National primary ambient air quality standards for sulfur oxides (sulfur dioxide).

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...National primary ambient air quality standards for sulfur oxides (sulfur dioxide). 50.17 Section 50.17 Protection...National primary ambient air quality standards for sulfur oxides (sulfur dioxide). (a) The level...

  12. 40 CFR 50.17 - National primary ambient air quality standards for sulfur oxides (sulfur dioxide).

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...National primary ambient air quality standards for sulfur oxides (sulfur dioxide). 50.17 Section 50.17 Protection...National primary ambient air quality standards for sulfur oxides (sulfur dioxide). (a) The level...

  13. Fate of excess sulfur in higher plants

    Microsoft Academic Search

    H Rennenberg

    1984-01-01

    The mechanisms which have evolved in higher plants to cope with excess sulfur in their environments are reviewed. Survival in a sulfur-rich environment is seldom achieved through avoidance of the intake of sulfur. The presence of excess sulfur in the soil or in the air usually results in an intake of excess sulfur into plants. An immediate injury by the

  14. Method of removing and recovering elemental sulfur from highly reducing gas streams containing sulfur gases

    DOEpatents

    Gangwal, Santosh K.; Nikolopoulos, Apostolos A.; Dorchak, Thomas P.; Dorchak, Mary Anne

    2005-11-08

    A method is provided for removal of sulfur gases and recovery of elemental sulfur from sulfur gas containing supply streams, such as syngas or coal gas, by contacting the supply stream with a catalyst, that is either an activated carbon or an oxide based catalyst, and an oxidant, such as sulfur dioxide, in a reaction medium such as molten sulfur, to convert the sulfur gases in the supply stream to elemental sulfur, and recovering the elemental sulfur by separation from the reaction medium.

  15. FTIR-ATR evaluation of topical skin protectants useful for sulfur mustard and related compounds

    NASA Astrophysics Data System (ADS)

    Braue, Ernest H., Jr.; Litchfield, Marty R.; Bangledorf, Catherine R.; Rieder, Robert G.

    1992-03-01

    The US Army has a need to develop topical protectants that can decrease the effects of cutaneous exposure to chemical warfare (CW) agents. Such materials would enhance a soldier's ability to carry out the mission in a chemically hostile environment, would lessen the burden on medical personnel, and may allow the casualties to return to duty in a shorter period of time than might otherwise be possible. In a preliminary report (E. H. Braue, Jr. and M. G. Pannella, Applied Spectrosc., 44, 1061 (1990)), we described a unique analytical method using FT-IR spectroscopy and the horizontal attenuated total reflectance (ATR) accessory for evaluating the effectiveness of topical skin protectants (TSPs) against penetration by chemical agents. We now describe the application of this method to the chemical warfare agent sulfur mustard (HD).

  16. Method of capturing sulfur

    SciTech Connect

    Stewart, R.D.; Gamble, R.L.

    1984-03-27

    A fluidized bed boiler, and a method of operating same in which air is passed through a grate to fluidize a bed of particulate material containing fossil fuel disposed on the grate. A raw acceptor for the sulfur produced as a result of the combustion of the fuel is introduced into the housing and confined within an area of the housing isolated from the bed of particulate material. The area containing the acceptor is maintained at conditions optimal for calcining the acceptor, after which the latter is introduced into the fluidized bed.

  17. Process for removing sulfur from sulfur-containing gases

    DOEpatents

    Rochelle, Gary T. (Austin, TX); Jozewicz, Wojciech (Chapel Hill, NC)

    1989-01-01

    The present disclosure relates to improved processes for treating hot sulfur-containing flue gas to remove sulfur therefrom. Processes in accorda The government may own certain rights in the present invention pursuant to EPA Cooperative Agreement CR 81-1531.

  18. Characterizing reduced sulfur compounds emissions from a swine concentrated animal feeding operation

    NASA Astrophysics Data System (ADS)

    Rumsey, Ian C.; Aneja, Viney P.; Lonneman, William A.

    2014-09-01

    Reduced sulfur compounds (RSCs) emissions from concentrated animal feeding operations (CAFOs) have become a potential environmental and human health concern, as a result of changes in livestock production methods. RSC emissions were determined from a swine CAFO in North Carolina. RSC measurements were made over a period of ?1 week from both the barn and lagoon during each of the four seasonal periods from June 2007 to April 2008. During sampling, meteorological and other environmental parameters were measured continuously. Seasonal hydrogen sulfide (H2S) barn concentrations ranged from 72 to 631 ppb. Seasonal dimethyl sulfide (DMS; CH3SCH3) and dimethyl disulfide (DMDS; CH3S2CH3) concentrations were 2-3 orders of magnitude lower, ranging from 0.18 to 0.89 ppb and 0.47 to 1.02 ppb, respectively. The overall average barn emission rate was 3.3 g day-1 AU-1 (AU (animal unit) = 500 kg of live animal weight) for H2S, which was approximately two orders of magnitude higher than the DMS and DMDS overall average emissions rates, determined as 0.017 g day-1 AU-1 and 0.036 g day-1 AU-1, respectively. The overall average lagoon flux was 1.33 ?g m-2 min-1 for H2S, which was approximately an order of magnitude higher than the overall average DMS (0.12 ?g m-2 min-1) and DMDS (0.09 ?g m-2 min-1) lagoon fluxes. The overall average lagoon emission for H2S (0.038 g day-1 AU-1) was also approximately an order of magnitude higher than the overall average DMS (0.0034 g day-1 AU-1) and DMDS (0.0028 g day-1 AU-1) emissions. H2S, DMS and DMDS have offensive odors and low odor thresholds. Over all four sampling seasons, 77% of 15 min averaged H2S barn concentrations were an order of magnitude above the average odor threshold. During these sampling periods, however, DMS and DMDS concentrations did not exceed their odor thresholds. The overall average barn and lagoon emissions from this study were used to help estimate barn, lagoon and total (barn + lagoon) RSC emissions from swine CAFOs in North Carolina. Total (barn + lagoon) H2S emissions from swine CAFOs in North Carolina were estimated to be 1.22*106 kg yr-1. The barns had significantly higher H2S emissions than the lagoons, contributing ?98% of total North Carolina H2S swine CAFO emissions. Total (barn + lagoon) emissions for DMS and DMDS were 1-2 orders of magnitude lower, with barns contributing ?86% and ?93% of total emissions, respectively. H2S swine CAFO emissions were estimated to contribute ?18% of North Carolina H2S emissions.

  19. Specific biocatalysis for coal sulfur speciation and removal

    SciTech Connect

    Kelly, R.M. (Johns Hopkins Univ., Baltimore, MD (USA). Dept. of Chemical Engineering); Olson, G.J. (National Inst. of Standards and Technology (IMSE), Gaithersburg, MD (USA). Polymers Div.)

    1990-05-01

    This project has as its objective the elucidation of sulfur speciation in coal through the use of microorganisms known to metabolize certain sulfur compounds. Using mesophilic organisms, such as Thiobacillus thiooxidans, and hyperthermophilic organisms, such as Pyrodictium brockii and Pyrococcus furiosus, which are sulfur metabolizers, several coals were probed for elemental sulfur and polysulfide content. The capability to ascertain the occurrence and amounts of these sulfur species in coal is important in examining several controversial hypotheses concerning the forms and transformations of organic sulfur in coal. The work thus far has illustrated the effectiveness of using a biologically-based assay for elemental sulfur and polysulfide in coal as well as provided a clearer picture of the mechanisms by which the organisms examined in this study solubilize and metabolize sulfur. 26 refs., 9 figs., 10 tabs.

  20. The Biogeochemistry of Sulfur in Hydrothermal Systems

    NASA Technical Reports Server (NTRS)

    Schulte, Mitchell; Rogers, K. L.; DeVincenzi, Donald L. (Technical Monitor)

    2001-01-01

    The incorporation of sulfur into many biomolecules likely dates back to the development of the earliest metabolic strategies. Sulfur is common in enzymes and co-enzymes and is an indispensable structural component in many peptides and proteins. Early metabolism may have been heavily influenced by the abundance of sulfide minerals in hydrothermal systems. The incorporation of sulfur into many biomolecules likely dates back to the development of the earliest metabolic strategies. Sulfur is common in enzymes and co-enzymes and is an indispensable structural component in many peptides and proteins. Early metabolism may have been heavily influenced by the abundance of sulfide minerals in hydrothermal systems. Understanding how sulfur became prevalent in biochemical processes and many biomolecules requires knowledge of the reaction properties of sulfur-bearing compounds. We have previously estimated thermodynamic data for thiols, the simplest organic sulfur compounds, at elevated temperatures and pressures. If life began in hydrothermal environments, it is especially important to understand reactions at elevated temperatures among sulfur-bearing compounds and other organic molecules essential for the origin and persistence of life. Here we examine reactions that may have formed amino acids with thiols as reaction intermediates in hypothetical early Earth hydrothermal environments. (There are two amino acids, cysteine and methionine, that contain sulfur.) Our calculations suggest that significant amounts of some amino acids were produced in early Earth hydrothermal fluids, given reasonable concentrations H2, NH3, H2S and CO. For example, preliminary results indicate that glycine activities as high as 1 mmol can be reached in these systems at 100 C. Alanine formation from propanethiol is also a favorable reaction. On the other hand, the calculated equilibrium log activities of cysteine and serine from propanethiol are -21 and -19, respectively, at 100 C. These results indicate that while amino acid formation with thiols as intermediates is favored in some cases, other mechanisms may have been necessary to produce significant amounts of other amino acids. Coupled with our previous results for thiols, these studies imply that sulfur may have been easily incorporated into the organic geochemistry of early Earth hydrothermal systems, leading to its widespread use in biomolecules. Formation of more complex biomolecules in hydrothermal systems may have required sulfur-bearing organic compounds as reaction intermediates.

  1. Effect of a variety of Chinese herbs and an herb-containing dentifrice on volatile sulfur compounds associated with halitosis: An in vitro analysis

    Microsoft Academic Search

    Ming-yu Li; Jun Wang; Zhu-ting Xu

    2010-01-01

    Background: The principal components of halitosis are volatile sulfur compounds (VSCs) such as hydrogen sulfide, methyl mercaptan, and dimethylsulfide or compounds such as butyric acid, propionic acid, putrescine, and cadaverine.Objective: The aim of this study was to evaluate the effect of Chinese herbs on VSCs in vitro.Methods: Saliva samples from volunteers were used as the source for the evaluation of

  2. 21 CFR 184.1095 - Sulfuric acid.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...sulfur dioxide (SO2 ) with oxygen and mixing the resultant sulfur trioxide (SO3 ) with water, or by reacting nitric oxide (NO) with sulfur dioxide and water. (b) The ingredient meets the specifications of the “Food...

  3. Biochemistry of Dissimilatory Sulfur Oxidation

    Microsoft Academic Search

    Blake II

    2003-01-01

    The long term goals of this research were to define the substrate oxidation pathways, the electron transport mechanisms, and the modes of energy conservation employed during the dissimilatory oxidation of sulfur practiced by various species of the thiobacilli. Specific adhesion of the thiobacilli to elemental sulfur was studied by electrical impedance, dynamic light scattering, laser Doppler velocimetry, and optical trapping

  4. SULFUR RETENTION IN COAL ASH

    EPA Science Inventory

    The report gives results of an analytical study to assess the potential for sulfur retention in various types of coal-fired boilers. Results of a field test of 10 industrial coal-fired boilers were used to evaluate the impact on sulfur retention of the operating variables (load a...

  5. Demonstrating Allotropic Modifications of Sulfur.

    ERIC Educational Resources Information Center

    McCarty, Jillian L.; Dragojlovic, Veljko

    2002-01-01

    Shows how a common demonstration that consists of slowly heating sulfur powder in a test tube to illustrate sulfur's allotropic modifications can convince students of conclusions about the moon Io which they often find surprising. Describes the demonstration in full. (Author/MM)

  6. Volume efficient sodium sulfur battery

    DOEpatents

    Mikkor, Mati (Ann Arbor, MI)

    1980-01-01

    In accordance with the teachings of this specification, a sodium sulfur battery is formed as follows. A plurality of box shaped sulfur electrodes are provided, the outer surfaces of which are defined by an electrolyte material. Each of the electrodes have length and width dimensions substantially greater than the thicknesses thereof as well as upwardly facing surface and a downwardly facing surface. An electrode structure is contained in each of the sulfur electrodes. A holding structure is provided for holding the plurality of sulfur electrodes in a stacked condition with the upwardly facing surface of one sulfur electrode in facing relationship to the downwardly facing surface of another sulfur electrode thereabove. A small thickness dimension separates each of the stacked electrodes thereby defining between each pair of sulfur electrodes a volume which receives the sodium reactant. A reservoir is provided for containing sodium. A manifold structure interconnects the volumes between the sulfur electrodes and the reservoir. A metering structure controls the flow of sodium between the reservoir and the manifold structure.

  7. Sulfur turnover and emissions during storage of cattle slurry: effects of acidification and sulfur addition.

    PubMed

    Eriksen, Jørgen; Andersen, Astrid J; Poulsen, Henrik V; Adamsen, Anders Peter S; Petersen, Søren O

    2012-01-01

    Slurry acidification using sulfuric acid reduces ammonia emissions but also affects sulfur (S) cycling. Emission of sulfur is a source of malodor and reduces the sulfur fertilizer value of the slurry. We investigated the effect of sulfate and methionine amendments, alone or in combination with acidification, on sulfur transformations in slurry and emissions of volatile sulfur compounds (VSC) during storage of fresh and aged cattle slurry. When pH was lowered to 5.5 it resulted in an almost complete inhibition of sulfate reduction. There was a huge emission of hydrogen sulfide (HS) with addition of sulfate and methionine ( < 0.01). Methanethiol (MT) was emitted in treatments with addition of methionine, especially when simultaneously acidified ( < 0.01). The large HS production in the sulfate-amended slurries resulted in little accumulation of MT and dimethyl sulfide (DMS) under neutral conditions, in contrast to acidic conditions where the degradation was inhibited and both MT and DMS accumulated. Based on odor activity values, untreated slurry had little odor development from S compounds, especially the aged slurry. Acidification did not significantly increase odor contribution from any of the compounds in fresh or aged slurry. Generally, addition of a sulfate increased the contribution from HS dramatically, whereas acidification lowered the HS contribution but increased that of MT. Thus, acidification of slurry with sulfuric acid may potentially produce more odor from S compounds than untreated slurry. PMID:23099955

  8. Theoretical studies of the marine sulfur cycle

    NASA Technical Reports Server (NTRS)

    Toon, Owen B.; Kasting, James B.; Liu, May S.

    1985-01-01

    Several reduced sulfur compounds are produced by marine organisms and then enter the atmosphere, where they are oxidized and ultimately returned to the ocean or the land. The oceanic dimethyl sulfide (DMS) flux, in particular, represents a significant fraction of the annual global sulfur input to the atmosphere. In the atmosphere, this gas is converted to sulfur dioxide (SO2), methane sulfonic acid, and other organic acids which are relatively stable and about which little is known. SO2 is a short lived gas which, in turn, is converted to sulfuric acid and other sulfate compounds which contribute significantly to acid rain. Because of the complexity of the sulfur system, it is not well understood even in the unperturbed atmosphere. However, a number of new observations and experiments have led to a significant increase in the understanding of this system. A number of one dimensional model experiments were conducted on the gas phase part of the marine sulfur cycle. The results indicate the measured concentration of DMS and the amplitude of its diurnal cycle are in agreement with estimates of its global flux. It was also found that DMS can make a large contribution to the background SO2 concentration in the free troposphere. Estimates of CS2 concentrations in the atmosphere are inconsistent with estimated fluxes; however, measured reaction rates are consistent with the observed steep tropospheric gradient in CS2. Observations of CS2 are extremely sparse. Further study is planned.

  9. Effect of Environmental Factors on Sulfur Gas Emissions from Problem Drywall

    E-print Network

    Effect of Environmental Factors on Sulfur Gas Emissions from Problem Drywall Randy Maddalena on Sulfur Gas Emissions from Problem Drywall Randy Maddalena Indoor Environment Department Environmental for volatile organic compounds (VOCs), aldehydes, reactive sulfur gases1 (RSGs) and volatile sulfur compounds2

  10. Post-SL9 Sulfur Photochemistry on Jupiter

    NASA Technical Reports Server (NTRS)

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

    1995-01-01

    We have modeled the photochemical evolution of the sulfur containing species that were observed in Jupiter's stratosphere after the Shoemaker Levy 9 (SL9) impacts. We find that most of the sulfur is converted to S8 in the first few days. Other important sulfur reservoirs are CS, whose abundance increases markedly with time, and possibly H2CS, HNCS, and NS, whose abundances depend on kinetic reaction rates that are unknown at the present. We discuss the temporal variation of the major sulfur compounds, make abundance and compositional predictions useful for comparison with observations, and discuss the possible condensation of sulfur containing species.

  11. Thermophilic Carbon-Sulfur-Bond-Targeted Biodesulfurization

    Microsoft Academic Search

    JIN KONISHI; YOSHITAKA ISHII; TOSHIMITU ONAKA; KOICHI OKUMURA; MASANORI SUZUKI

    1997-01-01

    Petroleum contains many heterocyclic organosulfur compounds refractory to conventional hydrodesulfu- rization carried out with chemical catalysts. Among these, dibenzothiophene (DBT) and DBTs bearing alkyl substitutions are representative compounds. Two bacterial strains, which have been identified as Paenibacillus strains and which are capable of efficiently cleaving carbon-sulfur (COS) bonds in DBT at high temperatures, have been isolated for the first time.

  12. The significance of glucosinolates for sulfur storage in Brassicaceae seedlings

    PubMed Central

    Aghajanzadeh, Tahereh; Hawkesford, Malcolm J.; De Kok, Luit J.

    2014-01-01

    Brassica juncea seedlings contained a twofold higher glucosinolate content than B. rapa and these secondary sulfur compounds accounted for up to 30% of the organic sulfur fraction. The glucosinolate content was not affected by H2S and SO2 exposure, demonstrating that these sulfur compounds did not form a sink for excessive atmospheric supplied sulfur. Upon sulfate deprivation, the foliarly absorbed H2S and SO2 replaced sulfate as the sulfur source for growth of B. juncea and B. rapa seedlings. The glucosinolate content was decreased in sulfate-deprived plants, though its proportion of organic sulfur fraction was higher than that of sulfate-sufficient plants, both in absence and presence of H2S and SO2. The significance of myrosinase in the in situ turnover in these secondary sulfur compounds needs to be questioned, since there was no direct co-regulation between the content of glucosinolates and the transcript level and activity of myrosinase. Evidently, glucosinolates cannot be considered as sulfur storage compounds upon exposure to excessive atmospheric sulfur and are unlikely to be involved in the re-distribution of sulfur in B. juncea and B. rapa seedlings upon sulfate deprivation. PMID:25566279

  13. The significance of glucosinolates for sulfur storage in Brassicaceae seedlings.

    PubMed

    Aghajanzadeh, Tahereh; Hawkesford, Malcolm J; De Kok, Luit J

    2014-01-01

    Brassica juncea seedlings contained a twofold higher glucosinolate content than B. rapa and these secondary sulfur compounds accounted for up to 30% of the organic sulfur fraction. The glucosinolate content was not affected by H2S and SO2 exposure, demonstrating that these sulfur compounds did not form a sink for excessive atmospheric supplied sulfur. Upon sulfate deprivation, the foliarly absorbed H2S and SO2 replaced sulfate as the sulfur source for growth of B. juncea and B. rapa seedlings. The glucosinolate content was decreased in sulfate-deprived plants, though its proportion of organic sulfur fraction was higher than that of sulfate-sufficient plants, both in absence and presence of H2S and SO2. The significance of myrosinase in the in situ turnover in these secondary sulfur compounds needs to be questioned, since there was no direct co-regulation between the content of glucosinolates and the transcript level and activity of myrosinase. Evidently, glucosinolates cannot be considered as sulfur storage compounds upon exposure to excessive atmospheric sulfur and are unlikely to be involved in the re-distribution of sulfur in B. juncea and B. rapa seedlings upon sulfate deprivation. PMID:25566279

  14. Inhibition of iron corrosion in sulfuric acid at elevated temperatures by bismuth(III) compounds

    SciTech Connect

    Nakai, K.; Nishihara, H.; Aramaki, K. [Keio Univ., Yokohama (Japan). Dept. of Chemistry

    1997-09-01

    Inhibition effects of bismuth(III) chloride (BiCl{sub 3}), bismuth(III) iodide (BiI{sub 3}), and a mixture of BiI{sub 3} and benzyl thiocyanate (C{sub 6}H{sub 5}CH{sub 2}SCN or BTC) on corrosion of iron (Fe) in 0.5 M sulfuric acid (H{sub 2}SO{sub 4}) at elevated temperatures were investigated using polarization measurements. The film formed on the Fe surface was analyzed by x-ray photoelectron spectroscopy (XPS) and electron probe microanalysis (EPMA). Because the anodic process of Fe corrosion was not suppressed, BiCl{sub 3} was an ineffective inhibitor at > 70 C. Since the anodic process was inhibited by specific adsorption of I{sup {minus}}, BiI{sub 3} at 1 {times} 10{sup {minus}4} M was highly efficient for inhibition of Fe corrosion in 0.5 M H{sub 2}SO{sub 4} at 90 C. The synergistic inhibitory effect of 1 {times} 10{sup {minus}4} M BiI{sub 3} and 4 {times} 10{sup {minus}3} M BTC resulted in a significantly high inhibitor efficiency (I{sub eff}) of 99.1% for Fe corrosion in 0.5 M H{sub 2}SO{sub 4} at 90 C. The cathodic process was suppressed by covering most of the surface with metallic bismuth (Bi). The anodic process was inhibited by coverage with the oxidative addition product of BTC at small spots uncoated with the Bi layer.

  15. The Science and Application of Critical Loads for Deposition of Nitrogen and Sulfur Compounds in National Parks

    NASA Astrophysics Data System (ADS)

    Porter, E.

    2008-12-01

    The National Parks of the U.S. contain resources of unsurpassed beauty and ecological significance. Park managers are directed to preserve the scenery and natural resources in these parks unimpaired for future generations. However, air pollution can damage the very resources that parks were created to preserve and, often, air pollution originates from outside park boundaries and therefore beyond the National Park Service's management jurisdiction. The Clean Air Act provides a framework and certain tools for protecting park resources from air pollution, but despite these programs, air pollution impacts to national park resources are widespread, including acidification or eutrophication from atmospheric deposition of nitrogen and sulfur compounds. Advances in ecosystem research and modeling have allowed national park managers to use critical loads to better evaluate ecosystem condition and set clear management goals for parks. Critical loads define the amount of deposition, usually nitrogen or sulfur compounds, below which harmful effects to a given resource are not expected. Resource protection goals based on critical loads, in turn, can be communicated to federal and State air regulatory agencies, and incorporated into air quality management planning for ecosystem protection. For example, the National Park Service, the Colorado Department of Public Health and Environment, and the Environmental Protection Agency have collaborated to use a critical load to set goals for a nitrogen deposition reduction plan to remedy ecosystem impacts in Rocky Mountain National Park. Elevated nitrogen deposition to the park has caused changes in the type and abundance of aquatic plant species, elevated levels of nitrate in surface waters, elevated levels of nitrogen in spruce needles, long-term accumulation of nitrogen in forest soils, and a shift in alpine tundra plant communities favoring sedges and grasses over the natural wildflower flora. The plan calls for nitrogen deposition to be reduced gradually over 20 years, to ultimately ensure ecosystem recovery and protection.

  16. The role of the sulfur globule proteins of Allochromatium vinosum : mutagenesis of the sulfur globule protein genes and expression studies by real-time RT-PCR

    Microsoft Academic Search

    Alexander Prange; Harald Engelhardt; Hans G. Trüper; Christiane Dahl

    2004-01-01

    During oxidation of reduced sulfur compounds, the purple sulfur bacterium Allochromatium vinosum stores sulfur in the periplasm in the form of intracellular sulfur globules. The sulfur in the globules is enclosed by a protein envelope that consists of the homologous 10.5-kDa proteins SgpA and SgpB and the smaller 8.5-kDa SgpC. Reporter gene fusions of sgpA and alkaline phosphatase showed the

  17. Process for production of synthesis gas with reduced sulfur content

    DOEpatents

    Najjar, Mitri S. (Hopewell Junction, NY); Corbeels, Roger J. (Wappingers Falls, NY); Kokturk, Uygur (Wappingers Falls, NY)

    1989-01-01

    A process for the partial oxidation of a sulfur- and silicate-containing carbonaceous fuel to produce a synthesis gas with reduced sulfur content which comprises partially oxidizing said fuel at a temperature in the range of 1800.degree.-2200.degree. F. in the presence of a temperature moderator, an oxygen-containing gas and a sulfur capture additive which comprises an iron-containing compound portion and a sodium-containing compound portion to produce a synthesis gas comprising H.sub.2 and CO with a reduced sulfur content and a molten slag which comprises (i) a sulfur-containing sodium-iron silicate phase and (ii) a sodium-iron sulfide phase. The sulfur capture additive may optionally comprise a copper-containing compound portion.

  18. Production of sulfur from sulfur dioxide obtained from flue gas

    SciTech Connect

    Miller, R.

    1989-06-06

    This patent describes a regenerable process for recovery of elemental sulfur from a gas containing sulfur dioxide comprising the steps of: contacting the gas with an aqueous, alkaline reaction medium containing sodium sulfite in concentration sufficient so that a slurry containing solid sodium sulfide is formed to react sulfur dioxide with sodium sulfite to form a solution containing dissolved sodium pyrosulfite and sodium sulfite; separating sulfur dioxide from the solution produced to leave a residual mixture containing water, sodium sulfite and a sodium pyrosulfite, the amount of sulfur dioxide separated being equal to about one-third the amount of sulfur dioxide which reacted with sodium sulfite; adding, in substantial absence of air, sufficient water and sodium bicarbonate to the residual mixture to react with the dissolved sodium pyrsulfide and form a slurry of solid sodium sulfite suspended in the resulting aqueous, alkaline reaction medium and gaseous carbon dioxide; separating the gaseous carbon dioxide; separating the solid sodium sulfite from the aqueous alkaline reaction medium and recycling the separated reaction medium; reducing the separated sodium sulfite to sodium sulfide; adding the sodium sulfide to an aqueous reaction medium containing sodium bicarbonate and, in the substantial absence of air, carbonating the resulting mixture with the gaseous carbon dioxide to form a slurry of solid particles of sodium bicarbonate dispersed in an aqueous reactor medium containing sodium bicarbonate, along with a gas composed primarily of hydrogen sulfide.

  19. Sulfur isotopes Laura Rosales-Lagarde

    E-print Network

    Lachniet, Matthew S.

    1 Sulfur isotopes Laura Rosales-Lagarde April 9th 2013 Figures from Seal et al. 2000 and Seal 2006 Significance v. 40, 541-602 Seal, R.R. II, 2006, Sulfur Isotope Geochemistry of Sulfide Minerals, in Vaughan D;2 Sulfur species #12;3 Mass-independent fractionation #12;4 #12;5 Sulfur and Oxygen isotopic secular

  20. SULFUR (S) Role of S in plants

    E-print Network

    Balser, Teri C.

    SULFUR #12;SULFUR (S) · Role of S in plants Component of amino acids Essential for nitrate reductase enzyme · Nitrate organic-N · Deficiency symptoms not localized #12;#12;#12;#12;POTENTIAL SULFUR DEFICIENCIES · Low organic matter soils · No recent manure history · Low sulfur in precipitation · Low subsoil

  1. Sulfur Dioxide Crossover during the Production of Hydrogen and Sulfuric Acid in a PEM Electrolyzer

    E-print Network

    Weidner, John W.

    Sulfur Dioxide Crossover during the Production of Hydrogen and Sulfuric Acid in a PEM Electrolyzer in the thermochemical conversion of sulfur dioxide to sulfuric acid for the large-scale production of hydrogen. Unfortunately, during operation, sulfur dioxide can diffuse from the anode to the cathode. This has several

  2. Graphene-sulfur nanocomposites for rechargeable lithium-sulfur battery electrodes

    SciTech Connect

    Liu, Jun; Lemmon, John P; Yang, Zhenguo; Cao, Yuiliang; Li, Xiaolin

    2014-06-17

    Rechargeable lithium-sulfur batteries having a cathode that includes a graphene-sulfur nanocomposite can exhibit improved characteristics. The graphene-sulfur nanocomposite can be characterized by graphene sheets with particles of sulfur adsorbed to the graphene sheets. The sulfur particles have an average diameter less than 50 nm..

  3. Sulfur-Free Selective Pulping

    E-print Network

    Dimmel, D. R.; Bozell, J. J.

    A joint research effort is being conducted on ways to produce cost-effective pulping catalysts from lignin. This project addresses improving selectivities and reducing the levels of sulfur chemicals used in pulping. Improved selectivity means...

  4. High copper level comulled and impregnated sulfur sorbent

    SciTech Connect

    Bishop, K.C.

    1981-03-31

    A porous sulfur sorbent is disclosed which has principal use in desulfurizing reformer feedstreams. The sorbent is prepared by peptizing alumina with acid and mulling the peptized alumina with a copper compound to form an extrudable dough. The dough is extruded, dried and impregnated with additional copper. The resulting sorbent has a higher capacity for adsorbing sulfur compounds than conventional prior art materials.

  5. TECHNIQUE FOR MEASURING REDUCED FORMS OF SULFUR IN AMBIENT AIR

    EPA Science Inventory

    A new technique for measuring low concentrations of volatile sulfur compounds in ambient air is discussed. The technique consists of preconcentration of sulfur compounds by chemisorption on gold metal coated sand or gold foil surface followed by thermal desorption, separation, an...

  6. System for reducing sulfur dioxide

    SciTech Connect

    Bischoff, W.F.; Steiner, P.

    1980-06-10

    A system for reducing sulfur dioxide in which a vessel is provided with an inlet for receiving coal and a plurality of gas distribution nozzles for receiving the sulfur dioxide and discharging same downwardly in the lower portion of the vessel for flowing upwardly in a counterflow relation to the coal. The coal flows through a distribution device located in the hopper section of the vessel for insuring an even distribution of coal through the vessel.

  7. 77 FR 20217 - Secondary National Ambient Air Quality Standards for Oxides of Nitrogen and Sulfur

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-04-03

    ...sulfur that retain the nitrogen and sulfur atoms from directly emitted oxides of nitrogen...various compounds with nitrogen or sulfur atoms that are associated with oxides of nitrogen...to nitrogen and sulfur, and not other atoms (e.g., H, C, O) whether...

  8. Compounds with mixed and intermediate sulfur valences as precursors of banded sulfides in carbonate-hosted Zn-Pb deposits in Belgium and Poland

    NASA Astrophysics Data System (ADS)

    Kucha, H.; Viaene, W.

    1993-01-01

    Compounds of Fe, Pb and Zn with mixed and intermediate sulfur valences form ubiquitous inclusions and relics in banded sphalerite, pyrite-melnikovite and galena. Banded sulfides continuously grade into banded compounds with mixed and intermediate sulfur valences, the latter with a fibrous microtexture. A fibrous microtexture is also shown by banded sphalerite and pyrite from Zn-Pb deposits of Belgium and Poland. It is therefore suggested that the fibrous sphalerite inherited such a microtexture, unusual for cubic ZnS, by direct replacement of a fibrous precursor with mixed and/or intermediate sulfur valences. The last band of banded sphalerite is often overgrown by idiomorphic, isometric sphalerite precipitated directly from the solution as ZnS. The following Fe, Pb and Zn compounds with mixed and intermediate sulfur valences were found in carbonate-hosted Zn-Pb deposits of Belgium and Poland: sulfoxylanes (M2+SO2; S2+), subsulfites (M2+S2O4; S3+), sulfites (M2+SO3; S4+), pyrosulfites (M2+S2O5; S4+) and thiosulphates(M2+S2O3; S2- and S6+).

  9. Photochemical oxidation and dispersion of gaseous sulfur compounds from natural and anthropogenic sources around a coastal location

    NASA Astrophysics Data System (ADS)

    Song, Sang-Keun; Shon, Zang-Ho; Kim, Ki-Hyun

    The photochemical oxidation and dispersion of reduced sulfur compounds (RSCs: H 2S, CH 3SH, DMS, CS 2, and DMDS) emitted from anthropogenic (A) and natural (N) sources were evaluated based on a numerical modeling approach. The anthropogenic emission concentrations of RSCs were measured from several sampling sites at the Donghae landfill (D-LF) (i.e., source type A) in South Korea during a series of field campaigns (May through December 2004). The emissions of natural RSCs in a coastal study area near the D-LF (i.e., source type N) were estimated from sea surface DMS concentrations and transfer velocity during the same study period. These emission data were then used as input to the CALPUFF dispersion model, revised with 34 chemical reactions for RSCs. A significant fraction of sulfur dioxide (SO 2) was produced photochemically during the summer (about 34% of total SO 2 concentrations) followed by fall (21%), spring (15%), and winter (5%). Photochemical production of SO 2 was dominated by H 2S (about 55% of total contributions) and DMS (24%). The largest impact of RSCs from source type A on SO 2 concentrations occurred around the D-LF during summer. The total SO 2 concentrations produced from source type N around the D-LF during the summer (a mean SO 2 concentration of 7.4 ppbv) were significantly higher than those (?0.3 ppbv) during the other seasons. This may be because of the high RSC and SO 2 emissions and their photochemistry along with the wind convergence.

  10. 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)

  11. A three-dimensional study of the tropospheric sulfur cycle

    Microsoft Academic Search

    M. Pham; J.-F. Müller; G. P. Brasseur; C. Granier; G. Mégie

    1995-01-01

    The global tropospheric distributions of seven important sulfur species were simulated with a global three-dimensional chemistry-transport model (IMAGES). Surface emission and deposition velocity maps were established for use as lower boundary conditions in the model. While anthropogenic SO2 emissions are by far the largest sulfur source in the northern midlatitudes, reduced sulfur compounds, notably dimethyl sulfide (DMS) predominate over most

  12. Method of treating coal to remove sulfur and ash

    SciTech Connect

    Brown, G.E.

    1981-12-15

    The present invention is directed to an improved method of chemically treating coal to remove sulfur and ash. It is especially adapted for use on high sulfur, refuse coal. In practice the coal is treated with hydrochloric acid and hypochlorous acid in the presence of ferric and ferrous sulfate to convert the iron pyrites to other sulfur compounds. These are then converted to various salts of calcium through neutralization with lime.

  13. Interactions between natural organic matter, sulfur, arsenic and iron oxides in re-oxidation compounds within riparian wetlands: NanoSIMS and X-ray adsorption spectroscopy evidences.

    PubMed

    Al-Sid-Cheikh, Maya; Pédrot, Mathieu; Dia, Aline; Guenet, Hélène; Vantelon, Delphine; Davranche, Mélanie; Gruau, Gérard; Delhaye, Thomas

    2015-05-15

    Arsenic (As) is a toxic and ubiquitous element which can be responsible for severe health problems. Recently, Nano-scale Secondary Ions Mass Spectrometry (nanoSIMS) analysis has been used to map organomineral assemblages. Here, we present a method adapted from Belzile et al. (1989) to collect freshly precipitated compounds of the re-oxidation period in a natural wetland environment using a polytetrafluoroethylene (PTFE) sheet scavenger. This method provides information on the bulk samples and on the specific interactions between metals (i.e. As) and the natural organic matter (NOM). Our method allows producing nanoSIMS imaging on natural colloid precipitates, including (75)As(-), (56)Fe(16)O(-), sulfur ((32)S(-)) and organic matter ((12)C(14)N) and to measure X-ray adsorption of sulfur (S) K-edge. A first statistical treatment on the nanoSIMS images highlights two main colocalizations: (1) (12)C(14)N(-), (32)S(-), (56)Fe(16)O(-) and (75)As(-), and (2) (12)C(14)N(-), (32)S(-) and (75)As(-). Principal component analyses (PCAs) support the importance of sulfur in the two main colocalizations firstly evidenced. The first component explains 70% of the variance in the distribution of the elements and is highly correlated with the presence of (32)S(-). The second component explains 20% of the variance and is highly correlated with the presence of (12)C(14)N(-). The X-ray adsorption near edge spectroscopy (XANES) on sulfur speciation provides a quantification of the organic (55%) and inorganic (45%) sulfur compositions. The co-existence of reduced and oxidized S forms might be attributed to a slow NOM kinetic oxidation process. Thus, a direct interaction between As and NOM through sulfur groups might be possible. PMID:25704268

  14. Neutralization and biodegradation of sulfur mustard

    SciTech Connect

    Harvey, S.P.; Beaudry, W.T.; Szafraniec, L.L. [and others

    1995-12-31

    One technology recommended for consideration for the disposal of the U.S. Chemical Stockpile is chemical neutralization followed by biodegradation. In the case of sulfur mustard ({open_quotes}mustard gas{close_quotes}, 2,2{prime}-dichlorodiethyl sulfide), alkaline hydrolysis yields a detoxified and biodegradable product. The hydrolysis reaction was studied with respect to the effects of temperature and sulfur mustard concentration on the rate and products of the reaction. A 28-fold overall rate enhancement was observed at 70{degrees}C vs. 30{degrees}C corresponding to an enthalpy of activation value of 17.9 Kcal/mole. Material balance studies conducted by {sup 1}H Nuclear Magnetic Resonance analysis showed that the products of the reaction consisted of thiodiglycol was relatively greater at lower sulfur mustard concentrations and higher temperatures. As temperatures were decreased or sulfur mustard concentrations was increased, the proportion of ether-type compounds increased accordingly. Conditions of 1% (vol//vol) sulfur mustard, 5% stoichiometric excess of NaOH and 90{degrees}C were selected for generation of the hydrolyzed bioreactor influent material. The bioreactor was seeded with activated sludge and was initially operated as 5 liter sequencing batch reactor with a hydraulic residence time of approximately days. Early results show total organic carbon removal of greater than 90%.

  15. Control of oxidative sulfur metabolism in Chlorobium

    SciTech Connect

    Maka, A.

    1986-01-01

    The photosynthetic, anaerobic microorganism Chlorobium limicola forma sp. thiosulfatophilum is being investigated as a possible biocatalyst for the removal of acid gases (primarily H/sub 2/S) generated by the hydroprocessing of fossil fuels. The organism was grown in an anaerobic, fed-batch photobioreactor which was continuously supplied with N/sub 2/, CO/sub 2/ and H/sub 2/S. The effect of light intensity, surface area of illuminated bioreactor, H/sub 2/S flow rate and various wavelength regions of light on oxidative sulfur metabolism by Chlorobium was examined. Light intensity, surface area of illuminated bioreactor, and H/sub 2/S flow rate regulated oxidative sulfur metabolism. The H/sub 2/S utilization rate increased with a corresponding increase in light intensity. The photoautotroph grew in any selected wavelength region with production of the various sulfur compounds, i.e., thiosulfate, sulfate, and sulfur. However, the rate of H/sub 2/S oxidation was wavelength dependent. The photosynthetic quantum efficiency (which is the molecules of sulfur (S/sup 0/) produced per photon utilized) was determined for this system. It is possible that the quantum efficiency can be used as a sufficiency factor for a photobioreactor. The sufficiency factor would be a unique characteristic of the reactor and demonstrate the relationship between light intensity and the rate of the light driven reaction. This sufficiency factor could be used for the determination of a light efficient photobioreactor.

  16. Sulfuric acid in the Venus clouds.

    NASA Technical Reports Server (NTRS)

    Sill, G. T.

    1972-01-01

    The extremely dry nature of the Venus upper atmosphere appears to demand the presence of an efficient desiccating agent as the chief constituent of the clouds of Venus. On the basis of polarization measures it is to be expected that this substance is present as spherical droplets, 1 to 2 microns in diameter, with a refractive index n of 1.46 plus or minus 0.02 at 3500A in the observed region of the atmosphere, with T about equal to 235 K. This substance must have ultraviolet, visible, and infrared reflection properties not inconsistent with the observed spectrum of Venus. Sulfuric acid, of about 86% by weight composition, roughly fulfills the first of these properties. The visible and ultraviolet transmission features of a thin layer of elemental bromine and hydrobromic acid dissolved in sulfuric acid somewhat resemble the Venus spectrum, up to 14 microns. The chemical process postulated for forming sulfuric acid involves the oxidation of sulfur and its compounds to sulfuric acid through the agency of elemental bromine produced by the photolytic decomposition of hydrogen bromide.

  17. 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. ine of the model compounds were biotransformed in aquifer slurries under sulfate-reducing or methanogenic conditions. he nitrogen and oxygen heterocyclic compounds were more susceptible to ...

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

    EPA Science Inventory

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

  19. Io's theothermal (sulfur) - Lithosphere cycle inferred from sulfur solubility modeling of Pele's magma supply

    NASA Astrophysics Data System (ADS)

    Battaglia, Steven M.; Stewart, Michael A.; Kieffer, Susan W.

    2014-06-01

    Surface deposits of volatile compounds such as water (Earth) or sulfur (Io) on volcanically active bodies suggest that a magmatic distillation process works to concentrate volatiles in surface reservoirs. On Earth, this is the combined hydrologic and tectonic cycle. On Io, sulfurous compounds are transferred from the interior to the surface reservoirs through a combination of a mantle-sourced magmatic system, vertical cycling of the lithosphere, and a sulfur-dominated crustal thermal system that we here call the "theothermal" system. We present a geochemical analysis of this process using previously inferred temperature and oxygen fugacity constraints of Pele's basaltic magma to determine the behavior of sulfur in the ionian magmas. Sulfate to sulfide ratios of Pele's magma are -4.084 ± 0.6 and -6.442 ± 0.7 log10 units, comparable to or lower than those of mid-ocean ridge basalts. This reflects the similarity of Io's oxidation state with Earth's depleted mantle as previously suggested by Zolotov and Fegley (Zolotov, M.Y., Fegley, B. [2000]. Geophys. Res. Lett. 27, 2789-2792). Our calculated limits of sulfur solubility in melts from Pele's patera (˜1100-1140 ppm) are also comparable to terrestrial mid-ocean ridge basalts, reflecting a compositional similarity of mantle sources. We propose that the excess sulfur obvious on Io's surface comes from two sources: (1) an insoluble sulfide liquid phase in the magma and (2) theothermal near-surface recycling.

  20. Sulfur in human nutrition and applications in medicine.

    PubMed

    Parcell, Stephen

    2002-02-01

    Because the role of elemental sulfur in human nutrition has not been studied extensively, it is the purpose of this article to emphasize the importance of this element in humans and discuss the therapeutic applications of sulfur compounds in medicine. Sulfur is the sixth most abundant macromineral in breast milk and the third most abundant mineral based on percentage of total body weight. The sulfur-containing amino acids (SAAs) are methionine, cysteine, cystine, homocysteine, homocystine, and taurine. Dietary SAA analysis and protein supplementation may be indicated for vegan athletes, children, or patients with HIV, because of an increased risk for SAA deficiency in these groups. Methylsulfonylmethane (MSM), a volatile component in the sulfur cycle, is another source of sulfur found in the human diet. Increases in serum sulfate may explain some of the therapeutic effects of MSM, DMSO, and glucosamine sulfate. Organic sulfur, as SAAs, can be used to increase synthesis of S-adenosylmethionine (SAMe), glutathione (GSH), taurine, and N-acetylcysteine (NAC). MSM may be effective for the treatment of allergy, pain syndromes, athletic injuries, and bladder disorders. Other sulfur compounds such as SAMe, dimethylsulfoxide (DMSO), taurine, glucosamine or chondroitin sulfate, and reduced glutathione may also have clinical applications in the treatment of a number of conditions such as depression, fibromyalgia, arthritis, interstitial cystitis, athletic injuries, congestive heart failure, diabetes, cancer, and AIDS. Dosages, mechanisms of action, and rationales for use are discussed. The low toxicological profiles of these sulfur compounds, combined with promising therapeutic effects, warrant continued human clinical trails. PMID:11896744

  1. Regulation of Dissimilatory Sulfur Oxidation in the Purple Sulfur Bacterium Allochromatium Vinosum

    PubMed Central

    Grimm, Frauke; Franz, Bettina

    2011-01-01

    In the purple sulfur bacterium Allochromatium vinosum, thiosulfate oxidation is strictly dependent on the presence of three periplasmic Sox proteins encoded by the soxBXAK and soxYZ genes. It is also well documented that proteins encoded in the dissimilatory sulfite reductase (dsr) operon, dsrABEFHCMKLJOPNRS, are essential for the oxidation of sulfur that is stored intracellularly as an obligatory intermediate during the oxidation of thiosulfate and sulfide. Until recently, detailed knowledge about the regulation of the sox genes was not available. We started to fill this gap and show that these genes are expressed on a low constitutive level in A. vinosum in the absence of reduced sulfur compounds. Thiosulfate and possibly sulfide lead to an induction of sox gene transcription. Additional translational regulation was not apparent. Regulation of soxXAK is probably performed by a two-component system consisting of a multi-sensor histidine kinase and a regulator with proposed di-guanylate cyclase activity. Previous work already provided some information about regulation of the dsr genes encoding the second important sulfur-oxidizing enzyme system in the purple sulfur bacterium. The expression of most dsr genes was found to be at a low basal level in the absence of reduced sulfur compounds and enhanced in the presence of sulfide. In the present work, we focused on the role of DsrS, a protein encoded by the last gene of the dsr locus in A. vinosum. Transcriptional and translational gene fusion experiments suggest a participation of DsrS in the post-transcriptional control of the dsr operon. Characterization of an A. vinosum ?dsrS mutant showed that the monomeric cytoplasmic 41.1-kDa protein DsrS is important though not essential for the oxidation of sulfur stored in the intracellular sulfur globules. PMID:21927612

  2. Identification, Synthesis, and Characterization of Novel Sulfur-Containing Volatile Compounds from the In-Depth Analysis of Lisbon Lemon Peels (Citrus limon L. Burm. f. cv. Lisbon).

    PubMed

    Cannon, Robert J; Kazimierski, Arkadiusz; Curto, Nicole L; Li, Jing; Trinnaman, Laurence; Ja?czuk, Adam J; Agyemang, David; Da Costa, Neil C; Chen, Michael Z

    2015-02-25

    Lemons (Citrus limon) are a desirable citrus fruit grown and used globally in a wide range of applications. The main constituents of this sour-tasting fruit have been well quantitated and characterized. However, additional research is still necessary to better understand the trace volatile compounds that may contribute to the overall aroma of the fruit. In this study, Lisbon lemons (C. limon L. Burm. f. cv. Lisbon) were purchased from a grove in California, USA, and extracted by liquid-liquid extraction. Fractionation and multidimensional gas chromatography-mass spectrometry were utilized to separate, focus, and enhance unidentified compounds. In addition, these methods were employed to more accurately assign flavor dilution factors by aroma extract dilution analysis. Numerous compounds were identified for the first time in lemons, including a series of branched aliphatic aldehydes and several novel sulfur-containing structures. Rarely reported in citrus peels, sulfur compounds are known to contribute significantly to the aroma profile of the fruit and were found to be aroma-active in this particular study on lemons. This paper discusses the identification, synthesis, and organoleptic properties of these novel volatile sulfur compounds. PMID:25639384

  3. The sulfurized InP surface

    SciTech Connect

    Wilmsen, C. W.; Geib, K. M.; Shin, J.; Iyer, R.; Lile, D. L.; Pouch, J. J.

    1989-07-01

    Sulfur treatments have previously been shown to improve the electrical characteristics of InP and GaAs devices. This paper reports the results of an Auger/x-ray photoelectron spectroscopy investigation of the InP surface after sulfur treatment. It is shown that the sulfur remains on the surface bonded to indium. There is no indication of elemental sulfur or sulfur bonded to phosphorus. This suggests that the sulfur has replaced phosphorus on the surface and has filled the phosphorus vacancies.

  4. Stable sulfur and carbon isotope investigations of pore-water and solid-phase compounds in sediments of the Chapopote Asphalt Volcano, southern Gulf of Mexico

    NASA Astrophysics Data System (ADS)

    Wilhelm, T.; Bruechert, V.; Pape, T.; Schubotz, F.; Kasten, S.

    2007-05-01

    During R/V Meteor cruise M67 2a/b (March-April 2006) to the Asphalt Volcanoes of the southern Gulf of Mexico two gravity cores were retrieved from the central depression of the Chapopote Knoll which contained viscous oil/asphalt a few meters below the sediment surface. Also several push cores were taken with the remotely operated vehicle (ROV) QUEST at sites where oil/asphalt reached closely below the sediment surface. From these cores solid-phase and pore-water samples were taken for on-board and subsequent shore-based analyses. Together with a core taken from a background site which is not influenced by asphalt/oil seepage these sediment and pore water samples are currently subject to detailed analyses of (1) the stable sulfur isotopic composition of both dissolved (sulfate and sulfide) and solid-phase (iron monosulfides, pyrite) sulfur compounds, and (2) the composition and stable carbon isotopic signatures of hydrocarbon gases. The major aims of these investigations are to identify whether and to which extent the upward migration of oil, asphalt and gas (1) stimulates biogeochemical processes and turn-over rates, and (2) influences the stable sulfur isotopic signatures of both dissolved and solid phase sulfur compounds. Furthermore, we seek to determine the potential of these - possibly unusual - stable sulfur isotopic signals of solid-phase sulfides to reconstruct hydrocarbon seepage in older geological records and to elucidate how the composition and the stable carbon isotopic signatures of the hydrocarbon gases are altered by the action of typical chemosynthetic communities thriving at these sites.

  5. On the Origin of Sulfur

    E-print Network

    Nils Ryde; David L. Lambert

    2005-10-05

    We present our work on the halo evolution of sulfur, based on observations of the S I lines around 9220 A for ten stars for which the S abundance was obtained previously from much weaker S I lines at 8694 A. We cannot confirm the rise and the high [S/Fe] abundances for low [Fe/H], as claimed in the literature from analysis of the 8694 A lines. The reasons for claims of an increase in [S/Fe] with decreasing [Fe/H] are probably twofold: uncertainties in the measurements of the weak 8694 A lines, and systematic errors in metallicity determinations from Fe I lines. The near-infrared sulfur triplet at 9212.9, 9228.1, and 9237.5 A are preferred for an abundance analysis of sulfur for metal-poor stars. Our work was presented in full by Ryde & Lambert (2004).

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

    SciTech Connect

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

    2012-01-14

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

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

    NASA Astrophysics Data System (ADS)

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

    2012-01-01

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

  8. PROTOTYPE CORRELATION MASK FLAME PHOTOMETRIC DETECTOR FOR MEASURING SULFUR DIOXIDE

    EPA Science Inventory

    A prototype flame photometric detector system (FPD) to measure gaseous sulfur compounds was fabricated using a previously developed correlation mask optical system and a new flame housing. Also, a new burner for the FPD system was optimized to view the excited molecular sulfur em...

  9. The Speciation of Sulfur in an Ocean on Europa

    NASA Technical Reports Server (NTRS)

    Zolotov, M. Yu.; Shock, E. L.

    2002-01-01

    Stability of native sulfur, iron sulfides, and aqueous sulfur compounds is evaluated at assumed P-T conditions of the Europa's ocean floor. Pyrite, gypsum, and ferric hydroxides can coexist in contact with sulfate-rich oceanic water. Additional information is contained in the original extended abstract.

  10. Dispersion and photochemical oxidation of reduced sulfur compounds in and around a large industrial complex in Korea

    NASA Astrophysics Data System (ADS)

    Song, Sang-Keun; Shon, Zang-Ho; Kim, Ki-Hyun; Kim, Yoo-Keun; Pal, Raktim

    In this study, the environmental behavior of reduced sulfur compounds (RSCs: H 2S, DMS, CS 2, DMDS, and CH 3SH) was investigated in an area influenced by strong anthropogenic processes based on a numerical modeling approach. The RSC emission concentrations were measured from multiple locations around the Ban-Wall industrial complex (BWIC) in the city of An San (AS), Korea, during a series of field campaigns held between August 2004 and September 2005. These emissions were then used as input for a CALPUFF dispersion model with the 34 dominant chemical reactions for RSCs. The impact of RSC emission on SO 2 concentrations was assessed further in the study areas. The model study indicated the possibility that RSCs emitted in and around the BWIC can exert a direct impact on the ambient SO 2 concentration levels in its surrounding areas with the most prominent effect observed during summer. Our prediction indicated that a significant fraction of SO 2 was produced photochemically in and around the BWIC during the summer (about 30% of total SO 2 concentrations) and fall events (˜20%). These photochemical productions of SO 2 were mainly ascribable to H 2S (˜60% of total contributions) and DMDS (˜25%) out of all five target RSCs. Meteorological contribution (dispersion) to SO 2 concentration level was also highest during summer.

  11. Images of Jupiter's sulfur ring

    NASA Technical Reports Server (NTRS)

    Pilcher, C. B.

    1980-01-01

    Images of the ring of singly ionized sulfur encircling Jupiter, obtained on two successive nights in April 1979, show that the ring characteristics may change dramatically in about 24 hr. On the first night the ring was narrow and confined to the magnetic equator inside Io's orbit. On the second night it was confined symmetrically about the centrifugal symmetry surface and showed considerable radial structure, including a 'fan' extending to Io's orbit. Many of the differences in the ring on the two nights can be explained in terms of differences in sulfur plasma temperature.

  12. Effectiveness of porous covers for control of ammonia, reduced sulfur compounds, total hydrocarbons, selected volatile organic compounds, and odor from hog manure storage lagoons.

    PubMed

    Regmi, Shekhar; Ongwandee, Maneerat; Morrison, Glenn; Fitch, Mark; Surampalli, Rao

    2007-06-01

    Anaerobic lagoons are a major source of odor at concentrated animal feeding operations. Seven different kinds of artificial (geotextile and polyethylene foam) and natural (straw and redwood) permeable lagoon covers were evaluated for their potential to reduce odorous emissions generated by anaerobic waste lagoons. A novel floating sampling raft was constructed and used to simultaneously evaluate the effectiveness of lagoon covers on an operating swine waste lagoon. The air collected from the raft was evaluated for odor, total reduced sulfur (TRS) compounds, ammonia, total hydrocarbons, dimethyldisulfide, and trimethylamine. The emission rates from the lagoon were highly variable both temporally and spatially. All of the lagoon covers substantially reduced TRS emissions and odor. Geotextile fabric and a recycled foam cover exhibited the greatest reduction in total hydrocarbon emissions; natural covers were less effective. Because of consistently low emission rates of ammonia, no statistically significant reduction of ammonia emissions were observed from any of the lagoon covers. PMID:17608010

  13. Six new tin-sulfur containing compounds obtained under solvothermal conditions

    NASA Astrophysics Data System (ADS)

    Pienack, Nicole; Lühmann, Henning; Seidlhofer, Beatrix; Ammermann, Janina; Zeisler, Christoph; Danker, Felix; Näther, Christian; Bensch, Wolfgang

    2014-07-01

    During explorative solvothermal syntheses six new compounds containing either the [Sn2S6]4- or the [SnS4]4- anion were obtained and structurally characterized: [Ni(1,2-dach)3]2Sn2S6·4H2O (1) (1,2-dach = trans-1,2-diaminocyclohexane), o-{[Ni(tepa)]2Sn2S6} (2) (tepa = tetraethylenepentamine), [Ni(peha)]2Sn2S6·H2O (3) (peha = pentaethylenehexamine), [Ni(aepa)]2Sn2S6 (4) (aepa = N-2-aminoethyl-1,3-propandiamine), [Co(dien)]2Sn2S6 (5) (dien = diethylenetriamine), and {[Mn(trien)]2SnS4} (trien = triethylenetetramine). In all compounds in-situ formed transition metal amine complexes act as charge compensating ligands or are bound to the thiostannate anions. Compound 2 is an orthorhombic polymorph of a recently published monoclinic compound. In compound 6 the very rare [Mn2N8S2] bi-octahedron is observed as main structural motif. This compound contains a one-dimensional chain which was also observed in a pseudo-polymorphic compound. The structures of all compounds are characterized by an extended hydrogen bonding network between S atoms of the anions and the H atoms of the amine ligands and/or water molecules.

  14. 40 CFR 60.642 - Standards for sulfur dioxide.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...the sulfur feed rate (X) and the sulfur content of the acid gas (Y) of the affected facility. (b) After demonstrating...the sulfur feed rate (X) and the sulfur content of the acid gas (Y) of the affected facility....

  15. Parameters Influencing Sulfur Speciation in Environmental Samples Using Sulfur K-Edge X-Ray Absorption Near-Edge Structure

    PubMed Central

    Pongpiachan, Siwatt; Thumanu, Kanjana; Kositanont, Charnwit; Schwarzer, Klaus; Prietzel, Jörg; Hirunyatrakul, Phoosak; Kittikoon, Itthipon

    2012-01-01

    This paper aims to enhance the credibility of applying the sulfur K-edge XANES spectroscopy as an innovative “fingerprint” for characterizing environmental samples. The sensitivities of sulfur K-edge XANES spectra of ten sulfur compound standards detected by two different detectors, namely, Lytle detector (LyD) and Germanium detector (GeD), were studied and compared. Further investigation on “self-absorption” effect revealed that the maximum sensitivities of sulfur K-edge XANES spectra were achieved when diluting sulfur compound standards with boron nitride (BN) at the mixing ratio of 0.1%. The “particle-size” effect on sulfur K-edge XANES spectrum sensitivities was examined by comparing signal-to-noise ratios of total suspended particles (TSP) and particulate matter of less than 10 millionths of a meter (PM10) collected at three major cities of Thailand. The analytical results have demonstrated that the signal-to-noise ratios of sulfur K-edge XANES spectra were positively correlated with sulfate content in aerosols and negatively connected with particle sizes. The combination of hierarchical cluster analysis (HCA) and principal component analysis (PCA) has proved that sulfur K-edge XANES spectrum can be used to characterize German terrestrial soils and Andaman coastal sediments. In addition, this study highlighted the capability of sulfur K-edge XANES spectra as an innovative “fingerprint” to distinguish tsunami backwash deposits (TBD) from typical marine sediments (TMS). PMID:23193498

  16. Parameters influencing sulfur speciation in environmental samples using sulfur k-edge x-ray absorption near-edge structure.

    PubMed

    Pongpiachan, Siwatt; Thumanu, Kanjana; Kositanont, Charnwit; Schwarzer, Klaus; Prietzel, Jörg; Hirunyatrakul, Phoosak; Kittikoon, Itthipon

    2012-01-01

    This paper aims to enhance the credibility of applying the sulfur K-edge XANES spectroscopy as an innovative "fingerprint" for characterizing environmental samples. The sensitivities of sulfur K-edge XANES spectra of ten sulfur compound standards detected by two different detectors, namely, Lytle detector (LyD) and Germanium detector (GeD), were studied and compared. Further investigation on "self-absorption" effect revealed that the maximum sensitivities of sulfur K-edge XANES spectra were achieved when diluting sulfur compound standards with boron nitride (BN) at the mixing ratio of 0.1%. The "particle-size" effect on sulfur K-edge XANES spectrum sensitivities was examined by comparing signal-to-noise ratios of total suspended particles (TSP) and particulate matter of less than 10 millionths of a meter (PM(10)) collected at three major cities of Thailand. The analytical results have demonstrated that the signal-to-noise ratios of sulfur K-edge XANES spectra were positively correlated with sulfate content in aerosols and negatively connected with particle sizes. The combination of hierarchical cluster analysis (HCA) and principal component analysis (PCA) has proved that sulfur K-edge XANES spectrum can be used to characterize German terrestrial soils and Andaman coastal sediments. In addition, this study highlighted the capability of sulfur K-edge XANES spectra as an innovative "fingerprint" to distinguish tsunami backwash deposits (TBD) from typical marine sediments (TMS). PMID:23193498

  17. 46 CFR 153.1046 - Sulfuric acid.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ...2010-10-01 false Sulfuric acid. 153.1046 Section 153.1046...SHIPS CARRYING BULK LIQUID, LIQUEFIED GAS, OR COMPRESSED GAS HAZARDOUS MATERIALS Operations...Procedures § 153.1046 Sulfuric acid. No person may liquefy...

  18. A SAW-Based Chemical Sensor for Detecting Sulfur-Containing Organophosphorus Compounds Using a Two-Step Self-Assembly and Molecular Imprinting Technology

    PubMed Central

    Pan, Yong; Yang, Liu; Mu, Ning; Shao, Shengyu; Wang, Wen; Xie, Xiao; He, Shitang

    2014-01-01

    This paper presents a new effective approach for the sensitive film deposition of surface acoustic wave (SAW) chemical sensors for detecting organophosphorus compounds such as O-ethyl-S-2-diisopropylaminoethyl methylphosphonothiolate (VX) containing sulfur at extremely low concentrations. To improve the adsorptive efficiency, a two-step technology is proposed for the sensitive film preparation on the SAW delay line utilizing gold electrodes. First, mono[6-deoxy-6-[(mercaptodecamethylene)thio

  19. Antibacterial and antifungal activity of sulfur-containing compounds from Petiveria alliacea L.

    PubMed

    Kim, Seokwon; Kubec, Roman; Musah, Rabi A

    2006-03-01

    A total of 18 organosulfur compounds originating from Petiveria alliacea L. roots have been tested for their antibacterial and antifungal activities. These represent compounds occurring in fresh homogenates as well as those present in various macerates, extracts and other preparations made from Petiveria alliacea. Of the compounds assayed, the thiosulfinates, trisulfides and benzylsulfinic acid were observed to be the most active, with the benzyl-containing thiosulfinates exhibiting the broadest spectrum of antimicrobial activity. The effect of plant sample preparation conditions on the antimicrobial activity of the extract is discussed. PMID:16229980

  20. Sulfur Species Investigation in Extra and Intracellular Sulfur Globules of Acidithiobacillus ferrooxidans and Acidithiobacillus caldus

    Microsoft Academic Search

    Huan He; Jin-Lan Xia; Hong-Chen Jiang; Yi Yan; Chang-Li Liang; Chen-Yan Ma; Lei Zheng; Yi-Dong Zhao; Guan-Zhou Qiu

    2010-01-01

    The sulfur chemical speciation in extracellular and intracellular sulfur globules of Acidithiobacillus ferrooxidans and Acidithiobacillus caldus were investigated with an integrated approach including scanning electron microscopy, transmission electron microscopy, energy dispersive spectroscopy and sulfur K-edge X-ray absorption near edge structure spectroscopy (XANES). The results indicated that both strains can accumulate extracellular sulfur globules when grown on thiosulfate, and the major

  1. December 2002 Issue #13 2002 SULFUR RESPONSES AND THE WISCONSIN ALFALFA SULFUR

    E-print Network

    Balser, Teri C.

    December 2002 Issue #13 ­ 2002 SULFUR RESPONSES AND THE WISCONSIN ALFALFA SULFUR SURVEY 1/ K to applied sulfur fertilizer in northern and western Wisconsin on lighter textured, low organic matter soils and Kelling, 1987). More recently, crop consultants and others have reported seeing sulfur responses on soils

  2. Sulfur Economy and Cell Wall Biosynthesis during Sulfur Limitation of Chlamydomonas reinhardtii1

    E-print Network

    Sulfur Economy and Cell Wall Biosynthesis during Sulfur Limitation of Chlamydomonas reinhardtii1 that specifically accumulate during sulfur limitation of Chlamydomonas reinhardtii. These polypeptides, present at high levels in the extracellular polypeptide fraction from a sulfur-deprived, cell wall-minus C

  3. Involvement of Intermediate Sulfur Species in Biological Reduction of Elemental Sulfur under Acidic, Hydrothermal Conditions

    E-print Network

    Ahmad, Sajjad

    Involvement of Intermediate Sulfur Species in Biological Reduction of Elemental Sulfur under Acidic-Purdue University, Indianapolis, Indianapolis, Indiana, USAb The thermoacidophile and obligate elemental sulfur (S8-phase sulfur during S8 0 -dependent batch culture growth. Cyclic voltammetry indicated the production

  4. Parallel, high-resolution carbon and sulfur isotope records of the evolving Paleozoic marine sulfur reservoir

    E-print Network

    Saltzman, Matthew R.

    Parallel, high-resolution carbon and sulfur isotope records of the evolving Paleozoic marine sulfur the biogeochemical cycles of carbon and sulfur are expressed in the evolving stable isotope composition of the ocean time, along with the sulfate sulfur isotope composition preserved as carbonate-associated sulfate (CAS

  5. Limits to Sulfur Accumulation in Transgenic Lupin Seeds Expressing a Foreign Sulfur-Rich Protein

    PubMed Central

    Tabe, Linda M.; Droux, Michel

    2002-01-01

    The low sulfur amino acid content of legume seeds restricts their nutritive value for animals. We have investigated the limitations to the accumulation of sulfur amino acids in the storage proteins of narrow leaf lupin (Lupinus angustifolius) seeds. Variation in sulfur supply to lupin plants affected the sulfur amino acid accumulation in the mature seed. However, when sulfur was in abundant supply, it accumulated to a large extent in oxidized form, rather than reduced form, in the seeds. At all but severely limiting sulfur supply, addition of a transgenic (Tg) sink for organic sulfur resulted in an increase in seed sulfur amino acid content. We hypothesize that demand, or sink strength for organic sulfur, which is itself responsive to environmental sulfur supply, was the first limit to the methionine (Met) and cysteine (Cys) content of wild-type lupin seed protein under most growing conditions. In Tg, soil-grown seeds expressing a foreign Met- and Cys-rich protein, decreased pools of free Met, free Cys, and glutathione indicated that the rate of synthesis of sulfur amino acids in the cotyledon had become limiting. Homeostatic mechanisms similar to those mediating the responses of plants to environmental sulfur stress resulted in an adjustment of endogenous protein composition in Tg seeds, even when grown at adequate sulfur supply. Uptake of sulfur by lupin cotyledons, as indicated by total seed sulfur at maturity, responded positively to increased sulfur supply, but not to increased demand in the Tg seeds. PMID:11891268

  6. Behavior of sulfur during coal pyrolysis

    USGS Publications Warehouse

    Shao, D.; Hutchinson, E.J.; Heidbrink, J.; Pan, W.-P.; Chou, C.-L.

    1994-01-01

    The behavior of sulfur in Illinois coals during pyrolysis was evaluated by thermogravimetry/ Fourier transform-infrared spectroscopy (TG/FT-IR) techniques. SO2, COS, and H2S were major gaseous sulfur-containing products observed during coal pyrolysis. The release rates of the gaseous sulfur species showed several peaks within the temperature ranges, which were due to the emission of different forms of sulfur in coal. ?? 1994.

  7. Validation of high performance liquid chromatography methods for determination of bioactive sulfur compounds in garlic bulbs

    Microsoft Academic Search

    Miyoung Yoo; Sanghee Lee; Sangil Lee; Homoon Seog; Dongbin Shin

    2010-01-01

    High performance liquid chromatography (HPLC) methods for determination of organosulfur compounds (OSCs) before their enzymatic\\u000a decomposition and allicin in garlic were optimized and validated. Four ?-glutamyl peptides, 2 S-alk(en)yl cysteine sulfoxides, and 2 S-alk(en)yl cysteine were simply extracted with water, followed by the sensitive and selective determination of all compounds\\u000a in a single run using reverse phase HPLC. Allicin was

  8. Synthesis, Structure and Reactivity of Two–Coordinate Mercury Alkyl Compounds with Sulfur Ligands: Relevance to Mercury Detoxification

    PubMed Central

    Melnick, Jonathan G.; Yurkerwich, Kevin; Parkin, Gerard

    2009-01-01

    The susceptibility of two-coordinate mercury alkyl compounds of the type X–Hg–R (where X is a monodentate sulfur donor) towards protolytic cleavage has been investigated as part of ongoing efforts to obtain information relevant to understanding the mechanism of action of the organomercurial lyase, MerB. Specifically, the reactivity of the two-coordinate mercury alkyl compounds PhSHgR, [mimBut]HgR and {[HmimBut]HgR}+ (HmimBut = 2-mercapto-1-t-butylimidazole; R = Me, Et) towards PhSH was investigated, thereby demonstrating that the ability to cleave the Hg–C bond is very dependent on the nature of the system. For example, whereas the reaction of PhSHgMe with PhSH requires heating at 145 °C for several weeks to liberate CH4, the analogous reaction of PhSHgEt with PhSH leads to evolution of C2H6 over the course of 2 days at 100 °C. Furthermore, protolytic cleavage of the Hg–C bond by PhSH is promoted by HmimBut. For example, whereas the reaction of {[HmimBut]HgEt}+ with PhSH eliminates C2H6 at elevated temperatures, the protolytic cleavage occurs over a period of 2 days at room temperature in the presence of HmimBut. The ability of HmimBut to promote the protolytic cleavage is interpreted in terms of the formation of a higher coordinate species {[HmimBut]nHgR}+ that is more susceptible to Hg–C bond cleavage than is two-coordinate {[HmimBut]HgR}+. These observations support the notion that access to a species with a coordination number greater than two is essential for efficient activity of MerB. PMID:20507113

  9. Model aging and oxidation effects on varietal, fermentative, and sulfur compounds in a dry botrytized red wine.

    PubMed

    Fedrizzi, Bruno; Zapparoli, Giacomo; Finato, Fabio; Tosi, Emanuele; Turri, Arianna; Azzolini, Michela; Versini, Giuseppe

    2011-03-01

    From harvest until wine arrives to the consumer, oxygen plays a crucial role in the definition of the final aroma. In the present research, the effect of the model oxidative aging on a dry red Botrytis wine, such as Italian Amarone, was considered. Amarone wine was submitted to model oxidative aging and then analyzed with two different approaches (SPE-GC-MS and HS-SPME/GC-MS). The same sampling plan was adopted to study the model aging of the same Amarone wine in anaerobic conditions. The HS-SPME/GC-MS method was applied to investigate for the first time the effect of the oxidative aging on a vast number of fermentative sulfur compounds. This research highlighted peculiar evolutions for several volatile compounds. In particular, benzaldehyde showed a sensitive increment during the oxidative aging, with a rate much higher than that reported for non-Botrytis red wines. On the other hand, several sulfides (dimethyl sulfide, 3-(methylthio)-1-propanol, etc.) disappeared after just 15 days of oxidative aging. A wine oxidation marker such as 3-(methylthio)-propanal was not found in any of the oxidized wines; conversely methionol-S-oxide was tentatively identified. This evidence has not been mentioned in the literature. A possible involvement of grape withering process and Botrytis in these mechanisms was supposed: a dry red wine, produced from the same but without any grape withering process and Botrytis infection (e.g., Bardolino wine), was submitted to oxidative aging and analysis. This red wine showed an evolution similar to those reported in the literature for dry red wines but significantly different from the Amarone wine. PMID:21314124

  10. Analysis of Organic Sulfur Compounds in Atmospheric Aerosols at the HKUST Supersite in Hong Kong Using HR-ToF-AMS.

    PubMed

    Huang, Dan Dan; Li, Yong Jie; Lee, Berto P; Chan, Chak K

    2015-03-17

    Organic sulfur compounds have been identified in ambient secondary organic aerosols, but their contribution to organic mass is not well quantified. In this study, using a high-resolution time-of-flight aerosol mass spectrometer (AMS), concentrations of organic sulfur compounds were estimated based on the high-resolution fragmentation patterns of methanesulfonic acid (MSA), and organosulfates (OS), including alkyl, phenyl, and cycloalkyl sulfates, obtained in laboratory experiments. Mass concentrations of MSA and minimum mass concentrations of OS were determined in a field campaign conducted at a coastal site of Hong Kong in September 2011. MSA and OS together accounted for at least 5% of AMS detected organics. MSA is of marine origin with its formation dominated by local photochemical activities and enhanced by aqueous phase processing. OS concentrations are better correlated with particle liquid water content (LWC) than with particle acidity. High-molecular-weight OS were detected in the continental influenced period probably because they had grown into larger molecules during long-range transport or they were formed from large anthropogenic precursors. This study highlights the importance of both aqueous-phase processing and regional influence, i.e., different air mass origins, on organic sulfur compound formation in coastal cities like Hong Kong. PMID:25700022

  11. Identification of components of electron transport chains in the extremely thermoacidophilic crenarchaeon Metallosphaera sedula through iron and sulfur compound oxidation transcriptomes.

    PubMed

    Auernik, Kathryne S; Kelly, Robert M

    2008-12-01

    The crenarchaeal order Sulfolobales collectively contain at least five major terminal oxidase complexes. Based on genome sequence information, all five complexes are found only in Metallosphaera sedula and Sulfolobus tokodaii, the two sequenced Sulfolobales capable of iron oxidization. While specific respiratory complexes in certain Sulfolobales have been characterized previously as proton pumps for maintaining intracellular pH and generating proton motive force, their contribution to sulfur and iron biooxidation has not been considered. For M. sedula growing in the presence of ferrous iron and reduced inorganic sulfur compounds (RISCs), global transcriptional analysis was used to track the response of specific genes associated with these complexes, as well as other known and putative respiratory electron transport chain elements. Open reading frames from all five terminal oxidase or bc(1)-like complexes were stimulated on one or more conditions tested. Components of the fox (Msed0467 to Msed0489) and soxNL-cbsABA (Msed0500 to Msed0505) terminal/quinol oxidase clusters were triggered by ferrous iron, while the soxABCDD' terminal oxidase cluster (Msed0285 to Msed0291) were induced by tetrathionate and S(0). Chemolithotrophic electron transport elements, including a putative tetrathionate hydrolase (Msed0804), a novel polysulfide/sulfur/dimethyl sulfoxide reductase-like complex (Msed0812 to Msed0818), and a novel heterodisulfide reductase-like complex (Msed1542 to Msed1550), were also stimulated by RISCs. Furthermore, several hypothetical proteins were found to have strong responses to ferrous iron or RISCs, suggesting additional candidates in iron or sulfur oxidation-related pathways. From this analysis, a comprehensive model for electron transport in M. sedula could be proposed as the basis for examining specific details of iron and sulfur oxidation in this bioleaching archaeon. PMID:18931292

  12. Identification of Components of Electron Transport Chains in the Extremely Thermoacidophilic Crenarchaeon Metallosphaera sedula through Iron and Sulfur Compound Oxidation Transcriptomes? †

    PubMed Central

    Auernik, Kathryne S.; Kelly, Robert M.

    2008-01-01

    The crenarchaeal order Sulfolobales collectively contain at least five major terminal oxidase complexes. Based on genome sequence information, all five complexes are found only in Metallosphaera sedula and Sulfolobus tokodaii, the two sequenced Sulfolobales capable of iron oxidization. While specific respiratory complexes in certain Sulfolobales have been characterized previously as proton pumps for maintaining intracellular pH and generating proton motive force, their contribution to sulfur and iron biooxidation has not been considered. For M. sedula growing in the presence of ferrous iron and reduced inorganic sulfur compounds (RISCs), global transcriptional analysis was used to track the response of specific genes associated with these complexes, as well as other known and putative respiratory electron transport chain elements. Open reading frames from all five terminal oxidase or bc1-like complexes were stimulated on one or more conditions tested. Components of the fox (Msed0467 to Msed0489) and soxNL-cbsABA (Msed0500 to Msed0505) terminal/quinol oxidase clusters were triggered by ferrous iron, while the soxABCDD? terminal oxidase cluster (Msed0285 to Msed0291) were induced by tetrathionate and S0. Chemolithotrophic electron transport elements, including a putative tetrathionate hydrolase (Msed0804), a novel polysulfide/sulfur/dimethyl sulfoxide reductase-like complex (Msed0812 to Msed0818), and a novel heterodisulfide reductase-like complex (Msed1542 to Msed1550), were also stimulated by RISCs. Furthermore, several hypothetical proteins were found to have strong responses to ferrous iron or RISCs, suggesting additional candidates in iron or sulfur oxidation-related pathways. From this analysis, a comprehensive model for electron transport in M. sedula could be proposed as the basis for examining specific details of iron and sulfur oxidation in this bioleaching archaeon. PMID:18931292

  13. High-sulfur coal for generating electricity

    Microsoft Academic Search

    J. T. Dunham; C. Rampacek; T. A. Henrie

    1974-01-01

    The use of high-sulfur coal from the Midwest and the Eastern U. S. is ; needed to help alleviate the shortages in energy production. U. S. pollution ; regulations on sulfur oxide emissions from power plants prohibit the use of this ; high-sulfur coal, but reliable flue gas desulfurization processes that permit ; burning of these coals without adverse environmental

  14. Genetic engineering of sulfur-degrading Sulfolobus

    SciTech Connect

    Ho, N.W.Y.

    1991-01-01

    The objectives of the proposed research is to first establish a plasmid-mediated genetic transformation system for the sulfur degrading Sulfolobus, and then to clone and overexpress the genes encoding the organic-sulfur-degrading enzymes from Sulfolobus- as well as from other microorganisms, to develop a Sulfolobus-based microbial process for the removal of both organic and inorganic sulfur from coal.

  15. 46 CFR 148.315 - Sulfur.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ...Materials § 148.315 Sulfur. (a) This part applies to lump or coarse grain powder sulfur only. Fine-grained powder (“flowers of sulfur”) may not be transported in bulk. (b) After the loading or unloading of lump or coarse grain powder...

  16. 46 CFR 148.315 - Sulfur.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ...Materials § 148.315 Sulfur. (a) This part applies to lump or coarse grain powder sulfur only. Fine-grained powder (“flowers of sulfur”) may not be transported in bulk. (b) After the loading or unloading of lump or coarse grain powder...

  17. Eagle-Picher Industries Sodium Sulfur Program

    NASA Technical Reports Server (NTRS)

    Silvey, Ronald L.

    1993-01-01

    Viewgraphs of the sodium sulfur program are presented. Sodium sulfur low earth orbit (LEO) cells are described. Topics covered include cell sizes, areas of improvement, and NaS cell testing. Sodium sulfur cell and battery designs continue to evolve with significant improvement demonstrated in resistance, rechargeability, cycle life, energy density, and electrolyte characterization.

  18. 8, 54135436, 2008 Ammonia in sulfuric

    E-print Network

    Boyer, Edmond

    ACPD 8, 5413­5436, 2008 Ammonia in sulfuric acid ion induced nucleation I. K. Ortega et al. Title.0 License. Atmospheric Chemistry and Physics Discussions The role of ammonia in sulfuric acid ion induced­5436, 2008 Ammonia in sulfuric acid ion induced nucleation I. K. Ortega et al. Title Page Abstract

  19. 46 CFR 148.315 - Sulfur.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ...2012-10-01 2012-10-01 false Sulfur. 148.315 Section 148.315 Shipping...for Certain Materials § 148.315 Sulfur. (a) This part applies to lump or coarse grain powder sulfur only. Fine-grained powder...

  20. 46 CFR 148.04-20 - Sulfur.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ...Shipping 5 2010-10-01 2010-10-01 false Sulfur. 148.04-20 Section 148.04-20 Shipping...Requirements for Certain Material § 148.04-20 Sulfur. (a) When sulfur is loaded in a deep hold with general cargo in the...

  1. Air Quality Criteria for Sulfur Oxides.

    ERIC Educational Resources Information Center

    National Air Pollution Control Administration (DHEW), Washington, DC.

    Included is a literature review which comprehensively discusses knowledge of the sulfur oxides commonly found in the atmosphere. The subject content is represented by the 10 chapter titles: Physical and Chemical Properties and the Atmospheric Reactions of the Oxides of Sulfur; Sources and Methods of Measurements of Sulfur Oxides in the Atmosphere;…

  2. 46 CFR 148.315 - Sulfur.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ...2014-10-01 2014-10-01 false Sulfur. 148.315 Section 148.315 Shipping...for Certain Materials § 148.315 Sulfur. (a) This part applies to lump or coarse grain powder sulfur only. Fine-grained powder...

  3. Images of Jupiter's sulfur ring

    Microsoft Academic Search

    C. B. Pilcher

    1980-01-01

    Images of the ring of singly ionized sulfur encircling Jupiter, obtained on two successive nights in April 1979, show that the ring characteristics may change dramatically in about 24 hr. On the first night the ring was narrow and confined to the magnetic equator inside Io's orbit. On the second night it was confined symmetrically about the centrifugal symmetry surface

  4. SULFUR DIOXIDE SOURCES IN AK

    EPA Science Inventory

    This map shows industrial plants which emit 100 tons/year or more of sulfur dioxide (SO2) in Alaska. The SO2 sources are plotted on a background map of cities and county boundaries. Data Sources: SO2 Sites: U.S. EPA AIRS System, County Outlines: 1990 Census Tiger Line Files 1:1...

  5. Exposure to liquid sulfur mustard

    Microsoft Academic Search

    Kurt G. Davis; Gary Aspera

    2001-01-01

    Chemical weapons continue to pose a serious threat to humanity. With the use of chemical weapons by terrorists in Tokyo, and the projected disarming of the chemical weapon stockpile in this country, the possibility that emergency physicians will encounter patients contaminated by chemical munitions, such as sulfur mustard, exists. Mustard is a vesicating agent with a long latency between exposure

  6. Seal for sodium sulfur battery

    DOEpatents

    Topouzian, Armenag (Birmingham, MI); Minck, Robert W. (Lathrup Village, MI); Williams, William J. (Northville, MI)

    1980-01-01

    This invention is directed to a seal for a sodium sulfur battery in which the sealing is accomplished by a radial compression seal made on a ceramic component of the battery which separates an anode compartment from a cathode compartment of the battery.

  7. Nutrient cyling in soils: Sulfur

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Sulfur (S) is an essential element required for normal plant growth, a fact that has been recognized since the nineteenth century. It is considered a secondary macronutrient, following the primary macronutrients nitrogen (N), phosphorus (P), and potassium (K), but is needed by plants at levels compa...

  8. Sulfur Dioxide and Material Damage

    ERIC Educational Resources Information Center

    Gillette, Donald G.

    1975-01-01

    This study relates sulfur dioxide levels with material damage in heavily populated or polluted areas. Estimates of loss were determined from increased maintenance and replacement costs. The data indicate a decrease in losses during the past five years probably due to decline in pollution levels established by air quality standards. (MR)

  9. Hydrogen v. Sulfur: Resolving the Debate on Electron Donor Use By Dominant Thermophilic bacteria Aquificales

    E-print Network

    Walker, Lawrence R.

    Hydrogen v. Sulfur: Resolving the Debate on Electron Donor Use By Dominant Thermophilic bacteria or preferentially use H2 as an electron donor (3). However, many members of the Aquificales can use sulfur compounds the use of sulfur compounds and H2 within monocultures of Aquificales. We used Thermocrinis ruber

  10. Possible Roles of Sulfur-Containing Amino Acids in a Chemoautotrophic Bacterium-Mollusc Symbiosis

    E-print Network

    McFall-Ngai, Margaret

    Possible Roles of Sulfur-Containing Amino Acids in a Chemoautotrophic Bacterium-Mollusc Symbiosis avoiding its toxic effects. The sulfur-containing free amino acids taurine and thiotaurine may function in sulfide detoxification by serving as sulfur storage compounds or as transport compounds between symbiont

  11. Analysis of the elemental sulfur bio-oxidation by Acidithiobacillus ferrooxidans with sulfur Kedge XANES

    Microsoft Academic Search

    Huan HeJin-lan XiaGuan-hua Huang; Jin-lan Xia; Guan-hua Huang; Hong-Chen Jiang; Xiu-Xiang Tao; Yi-Dong Zhao; Wei He

    Elemental sulfur bio-oxidation by the typical acidophilic sulfur-oxidizing microbe Acidithiobacillus ferrooxidans was investigated by using the technique of sulfur K-edge XANES spectroscopy. Our results showed that the majority of elemental\\u000a sulfur altered by A. ferrooxidans was dissolved into the organic phase containing carbon disulfide, while a part of it floated. The fitted results of sulfur\\u000a K-edge XANES spectrum of the

  12. Sulfur-oxidizing Bacteria: A Novel Bioinoculant for Sulfur Nutrition and Crop Production

    Microsoft Academic Search

    R. Anandham; P. Indira Gandhi; M. SenthilKumar; R. Sridar; P. Nalayini; Tong-Min Sa

    \\u000a Sulfur is an essential nutrient for plant growth as sulfur-deficient conditions cause severe losses in crop yield. Sulfur\\u000a nutrition has received little attention for many years, since fertilizers and atmospheric inputs have provided adequate amounts.\\u000a However, recent reductions in sulfur inputs from atmospheric depositions have resulted in a negative sulfur balance in agricultural\\u000a soils, making crop plants increasingly dependent on

  13. A design strategy applied to sulfur resistant lean NOx̳ automotive catalysts

    E-print Network

    Tang, Hairong

    2005-01-01

    Catalyst poisoning due to sulfur compounds derived from fuel sulfur presents a major challenge, intractable thus far, to development of many advanced technologies for automotive catalysts such as the lean NOx, trap. Under ...

  14. Rhodanese Functions as Sulfur Supplier for Key Enzymes in Sulfur Energy Metabolism

    PubMed Central

    Aussignargues, Clément; Giuliani, Marie-Cécile; Infossi, Pascale; Lojou, Elisabeth; Guiral, Marianne; Giudici-Orticoni, Marie-Thérèse; Ilbert, Marianne

    2012-01-01

    How microorganisms obtain energy is a challenging topic, and there have been numerous studies on the mechanisms involved. Here, we focus on the energy substrate traffic in the hyperthermophilic bacterium Aquifex aeolicus. This bacterium can use insoluble sulfur as an energy substrate and has an intricate sulfur energy metabolism involving several sulfur-reducing and -oxidizing supercomplexes and enzymes. We demonstrate that the cytoplasmic rhodanese SbdP participates in this sulfur energy metabolism. Rhodaneses are a widespread family of proteins known to transfer sulfur atoms. We show that SbdP has also some unusual characteristics compared with other rhodaneses; it can load a long sulfur chain, and it can interact with more than one partner. Its partners (sulfur reductase and sulfur oxygenase reductase) are key enzymes of the sulfur energy metabolism of A. aeolicus and share the capacity to use long sulfur chains as substrate. We demonstrate a positive effect of SbdP, once loaded with sulfur chains, on sulfur reductase activity, most likely by optimizing substrate uptake. Taken together, these results lead us to propose a physiological role for SbdP as a carrier and sulfur chain donor to these key enzymes, therefore enabling channeling of sulfur substrate in the cell as well as greater efficiency of the sulfur energy metabolism of A. aeolicus. PMID:22496367

  15. Protective action of ascorbic acid and sulfur compounds against acetaldehyde toxicity: implications in alcoholism and smoking.

    PubMed

    Sprince, H; Parker, C M; Smith, G G; Gonzales, L J

    1975-05-01

    Acetaldehyde is a toxic substance common to heavy drinking of alcohol and heavy smoking of cigarettes. It has been implicated thereby in diseases of the cardiovascular, respiratory, and central nervous systems. Protection against acetaldehyde toxicity (i.e. anesthesia and lethality) was studied in rats by oral intubation of test compounds 30-45 minutes prior to oral intubation of a standardized oral LD 90 dose (18 millimoles/kilogram) of acetaldehyde. Animals were monitored for anesthesia (loss of righting reflexes) and lethality for 72 hours. A total of 18 compounds was tested. L-ascorbic acid at 2 millimoles/kilogram (mM/kg) showed moderate protection against anesthesia and marked protection against lethality. Greatest protection against anesthesia and lethality was obtained at 2 m M/kg with each of the following: L-cysteine, N-acetyl-L-cysteine, thiamin-HCl, sodium metabisulfite, and L-cysteic acid. A combination of L-ascorbic acid with L-cysteine, and thiamin-HCl at reduced dose levels (2.0, 1.0 and 0.3 mM/kg, respectively) gave virtually complete protection. A detailed literature review is presented of the rationale and significance of these findings. Our findings could point the way to a possible build-up of natural protection against the chronic body insult of acetaldehyde arising from heavy drinking of alcohol and heavy smoking of cigarettes. PMID:1171591

  16. INDUSTRIAL PROCESS PROFILES FOR ENVIRONMENTAL USE: CHAPTER 23. SULFUR, SULFUR OXIDES AND SULFURIC ACID

    EPA Science Inventory

    The catalog of Industrial Process Profiles for Environmental Use was developed as an aid in defining the environmental impacts of industrial activity in the United States. Entries for each industry are in consistent format and form separate chapters of the study. The sulfur indus...

  17. Kinetics of Cisplatin and its monohydrated complex with sulfur-containing compounds designed for local otoprotective administration.

    PubMed

    Videhult, Pernilla; Laurell, Göran; Wallin, Inger; Ehrsson, Hans

    2006-11-01

    The anticancer drug cisplatin can cause permanent inner ear damage. We have determined the second-order degradation rate constant, k(Nu), of cisplatin and its more toxic monohydrated complex (MHC) in the presence of each of the sulfur-containing nucleophiles N-acetyl-l-cysteine, l-cysteine methyl ester, 1,3-dimethyl-2-thiourea, d-methionine, and thiosulfate, compounds that are under evaluation for local administration to prevent cisplatin-induced ototoxicity. MHC was isolated from a hydrolysis solution of cisplatin using liquid chromatography (LC). The degradations were evaluated by measuring the disappearance of MHC and cisplatin at 37 degrees C and pH 7.4 in the presence of each of the nucleophiles using LC and photometric detection. The k(Nu) of MHC and of cisplatin was 0.044 M(-1)sec(-1) and 0.012 M(-1)sec(-1) with N-acetyl-l-cysteine, 0.24 M(-1)sec(-1) and 0.067 M(-1)sec(-1) with l-cysteine methyl ester, 0.16 M(-1)sec(-1) and 0.074 M(-1)sec(-1) with 1,3-dimethyl-2-thiourea, 0.070 M(-1)sec(-1) and 0.069 M(-1)sec(-1) with d-methionine, and 3.9 M(-1)sec(-1) and 0.091 M(-1)sec(-1) with thiosulfate, respectively. Our results suggest that thiosulfate, as being the strongest nucleophile, is a promising candidate for local application in order to reduce the inner ear content of MHC and cisplatin. However, otoprotection is a multifactorial event, and it remains to be established how important nucleophilicity is for the effectiveness of the protecting agent. PMID:17060685

  18. Effects of oil drops containing Lactobacillus salivarius WB21 on periodontal health and oral microbiota producing volatile sulfur compounds.

    PubMed

    Suzuki, Nao; Tanabe, Kazunari; Takeshita, Toru; Yoneda, Masahiro; Iwamoto, Tomoyuki; Oshiro, Sueko; Yamashita, Yoshihisa; Hirofuji, Takao

    2012-03-01

    The objective of this paper is to evaluate the effects of oil drops containing Lactobacillus salivarius WB21 on periodontal health and oral microbiota producing volatile sulfur compounds (VSCs). For this study, 42 subjects were randomly assigned to receive oil samples containing L. salivarius WB21 or a placebo for two weeks. Oral assessment and saliva collection were performed on days 1 and 15. Bacterial analysis was performed using the real-time polymerase chain reaction and terminal restriction fragment length polymorphism (T-RFLP). In both the experimental and placebo groups, the average probing depth, number of periodontal pockets, and the percentage of bleeding on probing (BOP) decreased while stimulated salivary flow increased on day 15. BOP was reduced in the experimental group compared with the placebo group (P = 0.010). In the experimental group, total bacterial numbers decreased, and the number of L. salivarius increased. The number of Prevotella intermedia, which is correlated with hydrogen sulfide concentration in mouth air, increased in the placebo group and did not change in the experimental group. T-RFLP analysis found that the peak area proportions representing Porphyromonas gingivalis, P. intermedia, Tannerella forsythensis, and Fusobacterium nucleatum decreased in the experimental group, although there was no significant change in the bacterial composition. Thus we observed oil drops containing L. salivarius WB21 improved BOP and inhibited the reproduction of total and VSC-producing periodontopathic bacteria compared with the placebo group, but also showed the limit of its efficacy in controlling VSCs producing and periodontal pathogens. PMID:22368259

  19. New cysteine-S-conjugate precursors of volatile sulfur compounds in bell peppers (Capsicum annuum L. cultivar).

    PubMed

    Starkenmann, Christian; Niclass, Yvan

    2011-04-13

    The objective of this study was to verify whether the volatile organic sulfur compounds recently discovered in bell pepper (Capsicum annuum, L. cultivars), such as the mercapto-ketones: 4-sulfanyl-2-heptanone and 2-sulfanyl-4-heptanone, the mercapto-alcohols: 4-sulfanyl-2-heptanol and 2-sulfanyl-4-heptanol, and heptane-2,4-dithiol, originate from their corresponding cysteine-S-conjugates. Analysis of aqueous extracts of red and green bell pepper by ultraperformance liquid chromatography-mass spectrometry with electrospray ionization in the positive mode (UPLC-MS ESI(+)) displayed masses corresponding to the expected cysteine-S-conjugates. To confirm this observation, four cysteine-S-conjugates were prepared as authentic samples: S-(3-hydroxy-1-methylhexyl)-L-cysteine, S-(3-hydroxy-1-propylbutyl)-L-cysteine, S-(3-oxo-1-propylbutyl)-L-cysteine, and (2R,2'R)-3,3'-(4-hydroxyheptane-2,6-diyl)bis(sulfanediyl) bis(2-aminopropanoic acid). By comparison with the fragmentation patterns and retention times of synthetic mixtures of cysteine-S-conjugate diastereoisomers, the natural occurrence of cysteine conjugates was confirmed in bell peppers. In addition, the cysteine-S-conjugates from red and green bell pepper extracts were concentrated by ion exchange chromatography and the fractions incubated with a ?-lyase (apotryptophanase). The liberated thiols were concentrated by affinity chromatography, and their occurrence, detected by gas chromatography-mass spectrometry, confirmed our predictions. Moreover, 3-sulfanyl-1-hexanol was also detected and the occurrence of S-(1(2-hydroxyethyl)butyl)-L-cysteine confirmed. A quantitative estimation based on external calibration curves, established by UPLC-MS ESI(+) in selected reaction monitoring mode, showed that cysteine-S-conjugates were present at concentrations in the range of 1 to 100 ?g/kg (±20%). PMID:21375341

  20. Metabolism of reduced methylated sulfur compounds in anaerobic sediments and by a pure culture of an estuarine methanogen

    SciTech Connect

    Kiene, R.P.; Oremland, R.S.; Catena, A.; Miller, L.G.; Capone, A.G.

    1986-11-01

    Addition of dimethylsulfide (DMS), dimethyldisulfide (DMDS), or methane thiol (MSH) to a diversity of anoxic aquatic sediments (e.g., fresh water, estuarine, alkaline/hypersaline) stimulated methane production. The yield of methane recovered from DMS was often 52 to 63%, although high concentrations of DMS (as well as MSH and DMDS) inhibited methanogenesis in some types of sediments. Production of methane from these reduced methylated sulfur compounds was blocked by 2-bromoethanesulfonic acid. Sulfate did not influence the metabolism of millimolar levels of DMS, DMDs, or MSH added to sediments. However, when DMS was added at approx.2-3=M levels as (/sup 14/C)DMS, metabolism by sediments resulted in a /sup 14/CH/sub 4///sup 14/CO/sub 2/ ratio of only 0.06. Addition of molybdate increased the ratio of 1.8, while 2-bromoethanesulfonic acid decreased it to 0, but did not block /sup 14/CO/sub 2/ production. These results indicate the methanogens and sulfate reducers compete for DMS when it is present at low concentrations; however, at high concentrations, DMS is a noncompetitive substrate for methanogens. Metabolism of DMS by sediments resulted in the appearance of MSH as a transient intermediate. A pure culture of an obligately methylotrophic estuarine methanogen was isolated which was capable of growth on DMS. Metabolism of DMS by the culture also resulted in the transient appearance of MSH, but the organism could grow on neither MSH nor DMDS. The culture metabolized (/sup 14/C)-DMS to yield a /sup 14/CH/sub 4///sup 14/CO/sub 2/ ratio of approx. 2.8.

  1. Metagenomic assessment of a sulfur-oxidizing enrichment culture derived from marine sediment

    Microsoft Academic Search

    Man-Young Jung; VinhHoa Pham; Soo-Je Park; So-Jeong Kim; Jong-Chan Chae; Yul Roh; Sung-Keun Rhee

    2010-01-01

    The biological oxidation of reduced sulfur compounds is a critically important process in global sulfur biogeochemistry. In\\u000a this study, we enriched from marine sediments under denitrifying conditions, chemolithotrophic sulfur oxidizers that could\\u000a oxidize a variety of reduced sulfur compounds: thiosulfate, tetrathionate, sulfide, and polysulfide. Two major phylotypes\\u000a of 16S rRNA gene (>99% identity in each phylotype) were detected in this

  2. Sulfur diagenesis in Everglades peat and origin of pyrite in coal

    Microsoft Academic Search

    Z. S. Altschuler; M. M. Schnepfe; C. C. Silber; F. O. Simon

    1983-01-01

    The pattern of sulfur transformation in peat across the Everglades basin indicates that pyrite formation in organic-rich swamps depends on the use of organic oxysulfur compounds in dissimilatory respiration by sulfur-reducing bacteria. This paragenesis explains the primary distribution of sulfur compounds in low-sulfur coals and possibly in most coals and many organic-rich soils and sediments. It also accounts for the

  3. Sulfur diagenesis in everglades peat and origin of pyrite in coal

    USGS Publications Warehouse

    Altschuler, Z.S.; Schnepfe, M.M.; Silber, C.C.; Simon, F.O.

    1983-01-01

    The pattern of sulfur transformation in peat across the Everglades basin indicates that pyrite formation in organic-rich swamps depends on the use of organic oxysulfur compounds in dissimilatory respiration by sulfur-reducing bacteria. This paragenesis explains the primary distribution of sulfur compounds in low-sulfur coals and possibly in most coals and many organic-rich soils and sediments. It also accounts for the occurrence of framboidal pyrite bound in fossil tissue in coal and sediments.

  4. Missing SO2 oxidant in the coastal atmosphere? - Evidence from high resolution measurements of OH and atmospheric sulfur compounds

    NASA Astrophysics Data System (ADS)

    Berresheim, H.; Adam, M.; Monahan, C.; O'Dowd, C.; Plane, J. M. C.; Bohn, B.; Rohrer, F.

    2014-01-01

    Diurnal and seasonal variations of gaseous sulfuric acid (H2SO4) and methane sulfonic acid (MSA) were measured in N.E. Atlantic air at the Mace Head atmospheric research station during the years 2010 and 2011. The measurements utilized selected ion/chemical ionization mass spectrometry (SI/CIMS) with a detection limit for both compounds of 4.3 × 10 4 cm-3 at 5 min signal integration. The H2SO4 and MSA gas-phase concentrations were analysed in conjunction with the condensational sink for both compounds derived from 3 nm-10 ?m (diameter) aerosol size distributions. Accommodation coefficients of 1.0 for H2SO4 and 0.12 for MSA were assumed leading to estimated atmospheric lifetimes of the order of 7 min and 25 min, respectively. With the SI/CIMS instrument in OH measurement mode alternating between OH signal and background (non-OH) signal evidence was obtained for the presence of one or more unknown oxidants of SO2 in addition to OH. Depending on the nature of the oxidant(s) their ambient concentration may be enhanced in the CIMS inlet system by additional production. The apparent unknown SO2 oxidant was additionally confirmed by direct measurements of SO2 in conjunction with calculated H2SO4 concentrations. The calculated concentrations were consistently lower than the measured concentrations by a factor 4.8 ± 3.4 when considering the oxidation of SO2 by OH as the only source of H2SO4. Both the OH and the background signal were also observed to increase significantly during daytime aerosol nucleation events, independent of the ozone photolysis frequency, J(O1D), and were followed by peaks in both H2SO4 and MSA concentrations. This suggests a strong relation between the unknown oxidant(s), OH chemistry, and the atmospheric photo-oxidation of biogenic iodine compounds. As to the identity of the oxidant(s), we have been able to exclude ClO, BrO, IO, and OIO as possible candidates based on ab initio calculations. Stabilized Criegee intermediates (sCI) produced from ozonolysis of alkenes potentially contribute to the oxidation efficiency of the coastal and marine atmosphere. However, analysis of the CIMS background signal in context with recently published kinetic data currently suggests that larger Criegee intermediates produced from ozonolysis play no significant role for SO2 oxidation in the marine atmosphere. The possibility of H2SO4 formation without SO2 as precursor or from SO2 oxidation by small sCI produced photolytically should be explored.

  5. ROLE OF SULFUR IN REDUCING PCDD AND PCDF FORMATION

    EPA Science Inventory

    Past research has suggested that the presence of sulfur (S) in municipal waste combustors (MWCs) can decrease downstream formation of chlorinated organic compounds, particularly polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs). Thus, co-firing a...

  6. Mechanism for sulfur acquisition by the alkanesulfonate monooxygenase system.

    PubMed

    Ellis, Holly R

    2011-12-01

    The bacterial alkanesulfonate monooxygenase system is involved in the acquisition of sulfur from organosulfonated compounds during limiting sulfur conditions. The reaction relies on an FMN reductase to supply reduced flavin to the monooxygenase enzyme. The reaction catalyzed by the alkanesulfonate monooxygenase enzyme involves the carbon-sulfur bond cleavage of a wide range of organosulfonated compounds. A C4a-(hydro)peroxyflavin is the oxygenating intermediate in the mechanism of desulfonation by the alkanesulfonate monooxygenase. This review discusses the physiological importance of this system, and the individual kinetic parameters and mechanistic properties of this enzyme system. PMID:21880344

  7. Comparison between pre-fractionation and fractionation process of heavy gas oil for determination of sulfur compounds using comprehensive two-dimensional gas chromatography.

    PubMed

    Machado, Maria Elisabete; Bregles, Lucas Panizzi; de Menezes, Eliana Weber; Caramão, Elina Bastos; Benvenutti, Edilson Valmir; Zini, Cláudia Alcaraz

    2013-01-25

    The separation of the organic sulfur compounds (OSC) of petroleum or its heavy fractions is a critical step and is essential for the correct characterization of these compounds, especially due to similar physical and chemical properties of polycyclic aromatic sulfur heterocycles (PASH) and polycyclic aromatic hydrocarbons (PAH). This similarity results in coelutions among PAH and PASH and for this reason former steps of fractionation are required before gas chromatographic analysis. The objective of this study was to evaluate the potential of GC×GC for the separation and identification of OSC in a heavy gas oil sample without fractionation, after pre-fractionation in an alumina column and also after fractionation process. This last one was performed with a modified stationary phase manufactured and characterized in the laboratory, called Pd(II)-MPSG, where palladium is chemically linked to silica through mercaptopropyl groups. The fractions obtained from both procedures were analyzed by GC×GC/TOFMS, which was effective to separate and identify various classes of OSC. A hundred and thirty-five compounds were tentatively identified in the sample that was only pre-fractionated. However, when the fractionation was also performed with the Pd(II)-MPSG phase, a larger number of sulfur compounds were found (317). Results have shown that the analysis of a pre-fractionated sample by GC×GC/TOFMS is suitable when the goal is a general characterization of classes of compounds in the sample, while a more detailed analysis of PASH can be performed, using also the fractionation Pd(II)-MPSG phase. GC×GC/TOFMS played a major role in the comparison of samples obtained from pre-fractionation and fractionation steps due to its high peak capacity, selectivity, organized distribution of chromatographic peaks and resolution. PMID:23298843

  8. Metal-sulfur type cell having improved positive electrode

    DOEpatents

    DeJonghe, L.C.; Visco, S.J.; Mailhe, C.C.; Armand, M.B.

    1988-03-31

    A novel metal-sulfur type cell operable at a temperature of 200/degree/C or less with an energy density of 150 Whrs/Kg or better is disclosed characterized by an organo-sulfur cathode formed from an organic-sulfur compound having the general formula, in its charged state, of (R(S)/sub y/)n wherein y = 1 to 6; n = 2 to 20; and R is one or more different aliphatic or aromatic organic moieties having 1 to 20 carbon atoms, which may include one or more oxygen, sulfur, or nitrogen heteroatoms when R comprises one or more aromatic rings, or one or more oxygen, sulfur, nitrogen, or fluorine atoms associated with the chain when R comprises an aliphatic chain, wherein the aliphatic group may be linear or branched, saturated or unsaturated, and wherein either the aliphatic chain or the aromatic ring may have substituted groups thereon. 4 figs.

  9. Metal-sulfur type cell having improved positive electrode

    DOEpatents

    Dejonghe, Lutgard C. (Berkeley, CA); Visco, Steven J. (Berkeley, CA); Mailhe, Catherine C. (Berkeley, CA); Armand, Michel B. (St. Martin D'Uriage, FR)

    1989-01-01

    An novel metal-sulfur type cell operable at a temperature of 200.degree. C. or less with an energy density of 150 Whrs/Kg or better is disclosed characterized by an organo-sulfur cathode formed from an organic-sulfur compound having the general formula, in its charged state, of (R(S).sub.y).sub.n wherein y=1 to 6; n=2 to 20; and R is one or more different aliphatic or aromatic organic moieties having 1 to 20 carbon atoms, which may include one or more oxygen, sulfur, or nitrogen heteroatoms when R comprisises one of more aromatic rings, or one or more oxygen, sulfur, nitrogen, or fluorine atoms associtated with the chain when R comprises an aliphatic chain, wherein the aliphatic group may be linear or branched, saturated or unsaturated, and wherein either the aliphatic chain or the aromatic ring may have substituted groups thereon.

  10. Biotic and abiotic carbon to sulfur bond cleavage. Final report

    SciTech Connect

    Frost, J.W.

    1994-05-01

    The microbial desulfurization of organosulfur compounds occurs by unprecedented and largely unexplored biochemical processes. A study of such biotic desulfurizations can be expected to give rise to new and useful chemistry and enzymology. The potential value of understanding and harnessing these processes is seen in relation to the need for methods for the removal of organically bound sulfur from coal and the degradation of organic sulfur-containing pollutants. This research effort has been directed towards an examination of desulfurization ability in well characterized microorganisms, the isolation of bacteria with desulfurization ability from natural sources, the characterization and mechanistic evaluation of the observed biocatalytic processes, the development of biomimetic synthetic organic chemistry based on biotic desulfurization mechanisms and the design and preparation of improved coal model compounds for use in microbial selection processes. A systematic approach to studying biodesulfurizations was undertaken in which organosulfur compounds have been broken down into classes based on the oxidation state of the sulfur atom and the structure of the rest of the organic material. Microbes have been evaluated in terms of ability to degrade organosulfur compounds with sulfur in its sulfonic acid oxidation state. These compounds are likely intermediates in coal desulfurization and are present in the environment as persistent pollutants in the form of detergents. It is known that oxygen bonded to sulfur lowers the carbon-sulfur bond energy, providing a thermodynamic basis for starting with this class of compounds.

  11. Analytical method for the evaluation of sulfur functionalities in American coals. Final report

    SciTech Connect

    Attar, A.

    1983-05-01

    This investigation consisted of the following 6 tasks: (1) improve the instrumentation for the sulfur functional groups analysis and make it more reliable. (2) create a set of reference standards of sulfur-containing compounds. (3) examine the sulfur groups distribution in untreated and desulfurized coals. (4) examine the sulfur functionalities in raw and processed coals, i.e., liquefied coals. (5) determine the distribution of sulfur functionalities in modified coals. (6) prepare computer programs for calculations related to the distribution of sulfur functional groups in coal. Each task is discussed and results are presented. Appendix A contains the computer program used to interpret the data. 31 references, 56 figures, 17 tables.

  12. Sodium Sulfur Technology Program Nastec

    NASA Technical Reports Server (NTRS)

    Highley, Bob; Somerville, W. Andrew

    1992-01-01

    The NaSTEC program focuses on developing currently available sodium sulfur cells for use in space applications and investigating the operational parameters of the cells. The specific goals of the program are to determine the operational parameters and verify safety limits of Na/S technology battery cells; test long term zero-g operation; and create a life test database. The program approach and ground and flight test objectives are described in textual and graphic form.

  13. Sulfur removal from high-sulfur Illinois coal by low-temperature perchloroethylene (PCE) extraction. Final technical report, 1 September, 1992--31 August, 1993

    SciTech Connect

    Chou, M.I.M.; Lytle, J.M.; Ruch, R.R.; Kruse, C.W.; Chaven, C.; Hackley, K.C.; Hughes, R.E.; Harvey, R.D.; Frost, J.K. [Illinois State Geological Survey, Champaign, IL (United States); Buchanan, D.H. [Eastern Illinois Univ., Charleston, IL (United States); Stucki, J.W. [Univ. of Illinois, Urbana, IL (United States); Huffman, G.P.; Huggins, F.E. [Univ. of Kentucky, Lexington, KY (United States)

    1993-12-31

    The Midwest Ore Processing Co. (MWOPC) has reported a precombustion coal desulfurization process using perchloroethylene (PCE) at 120 C to remove up to 70% of the organic sulfur. The purposes of this research were to independently confirm and possibly to improve the organic sulfur removal from Illinois coals with the PCE desulfurization and to verify the ASTM forms-of-sulfur determination for evaluation of the process. An additional goal was to develop a dechlorination procedure to remove excess PCE from the PCE-treated coal. A laboratory scale operation of the MWOPC PCE desulfurization process was demonstrated, and a dechlorination procedure to remove excess PCE from the PCE-treated coal was developed. The authors have determined that PCE desulfurization removed mainly elemental sulfur from coal. The higher the level of coal oxidization, the larger the amount of elemental sulfur that is removed by PCE extraction. The increased elemental sulfur during short-term preoxidation is found to be pH dependent and is attributed to coal pyrite oxidation under acidic (pH < 2) conditions. The non-ASTM sulfur analyses confirmed the hypothesis that the elemental sulfur produced by oxidation of pyrite complicates the interpretation of analytical data for PCE process evaluations when only the ASTM forms-of-sulfur is used. When the ASTM method is used alone, the elemental sulfur removed during PCE desulfurization is counted as organic sulfur. A study using model compounds suggests that mild preoxidation treatment of coal described by MWOPC for removal of organic sulfur does not produce enough oxidized organic sulfur to account for the amounts of sulfur removal reported. Furthermore, when oxidation of coal-like organosulfur compounds does occur, the products are inconsistent with production of elemental sulfur, the product reported by MWOPC. Overall, it is demonstrated that the PCE process is not suitable for organic sulfur removal.

  14. Investigating missing sources of sulfur at Fairbanks, Alaska.

    PubMed

    Shakya, Kabindra M; Peltier, Richard E

    2013-08-20

    We investigated disparities in elemental sulfur and inorganic sulfate concentrations in ambient fine particulate matter (PM2.5) data from 2005 to 2012 at a monitoring station in Fairbanks, AK. In approximately 28% of the observations from 2005 to 2012, elemental sulfur by X-ray fluorescence (XRF) spectroscopy significantly exceeded the inorganic sulfur by ion chromatography (IC), suggesting the presence of a significant quantity of unmeasured sulfur compounds. The mean ratio of sulfur by XRF to that by IC for only these cases was 1.22 ± 0.11. The largest discrepancies between elemental sulfur and sulfate were most frequently observed in the summer, although discrepancies were observed year round. Assuming the additional sulfur (other than inorganic sulfate) as the upper limit estimate, this work shows that organosulfur species (or the additional sulfur) account for 1.29% of organic carbon (OC) and 0.75% of PM2.5 in Fairbanks. An analysis of all available air quality system (AQS) data suggests that these recurring phenomena are linked to seasons, total carbon, inorganic nitrate, and elemental sources during cold periods and ozone during warm periods. PMID:23927829

  15. Sulfur-impregnated disordered carbon nanotubes cathode for lithium-sulfur batteries.

    PubMed

    Guo, Juchen; Xu, Yunhua; Wang, Chunsheng

    2011-10-12

    The commercialization of lithium-sulfur batteries is hindered by low cycle stability and low efficiency, which are induced by sulfur active material loss and polysulfide shuttle reaction through dissolution into electrolyte. In this study, sulfur-impregnated disordered carbon nanotubes are synthesized as cathode material for the lithium-sulfur battery. The obtained sulfur-carbon tube cathodes demonstrate superior cyclability and Coulombic efficiency. More importantly, the electrochemical characterization indicates a new stabilization mechanism of sulfur in carbon induced by heat treatment. PMID:21928817

  16. Predictive sulfur metabolism - a field in flux.

    PubMed

    Calderwood, Alexander; Morris, Richard J; Kopriva, Stanislav

    2014-01-01

    The key role of sulfur metabolites in response to biotic and abiotic stress in plants, as well as their importance in diet and health has led to a significant interest and effort in trying to understand and manipulate the production of relevant compounds. Metabolic engineering utilizes a set of theoretical tools to help rationally design modifications that enhance the production of a desired metabolite. Such approaches have proven their value in bacterial systems, however, the paucity of success stories to date in plants, suggests that challenges remain. Here, we review the most commonly used methods for understanding metabolic flux, focusing on the sulfur assimilatory pathway. We highlight known issues with both experimental and theoretical approaches, as well as presenting recent methods for integrating different modeling strategies, and progress toward an understanding of flux at the whole plant level. PMID:25477892

  17. Predictive sulfur metabolism – a field in flux

    PubMed Central

    Calderwood, Alexander; Morris, Richard J.; Kopriva, Stanislav

    2014-01-01

    The key role of sulfur metabolites in response to biotic and abiotic stress in plants, as well as their importance in diet and health has led to a significant interest and effort in trying to understand and manipulate the production of relevant compounds. Metabolic engineering utilizes a set of theoretical tools to help rationally design modifications that enhance the production of a desired metabolite. Such approaches have proven their value in bacterial systems, however, the paucity of success stories to date in plants, suggests that challenges remain. Here, we review the most commonly used methods for understanding metabolic flux, focusing on the sulfur assimilatory pathway. We highlight known issues with both experimental and theoretical approaches, as well as presenting recent methods for integrating different modeling strategies, and progress toward an understanding of flux at the whole plant level. PMID:25477892

  18. Reactivity of [Fe 2(CO) 6(?-CO)(?-dppm)] towards unsaturated sulfur-containing compounds, SO 2, CS 2 and ArNCS: facile carbon–sulfur bond cleavage at the diiron centre

    Microsoft Academic Search

    Graeme Hogarth; Mark H Lavender; Khalid Shukri

    2000-01-01

    Photolysis of [Fe2(CO)6(?-CO)(?-dppm)] (1) with SO2, CS2 and ArNCS leads to the formation of [Fe2(CO)6(?-SO2)(?-dppm)] (2), [Fe4(CO)10(?3-S)(?-CS)(?-dppm)2] (3), [Fe2(CO)3(CNAr){?-SC(NAr)C(O)S}(?-dppm)] (4–5) and [Fe2(CO)4{?-SC(N-p-tolyl)C(O)S}(?-dppm)] (6), respectively. Complex 2 is a simple CO substitution product, while in 3 carbon–sulfur cleavage and coupling of diiron units has occurred. Dithiolate-bridged 4–6 also result from carbon–sulfur bond cleavage of one isothiocyanate and coupling of the sulfur

  19. Prebiotic Synthesis of Methionine and Other Sulfur-Containing Organic Compounds on the Primitive Earth: A Contemporary Reassessment Based on an Unpublished 1958 Stanley Miller Experiment

    NASA Technical Reports Server (NTRS)

    Parker, Eric T.; Cleaves, H. James; Callahan, Michael P.; Dworkin, Jason P.; Glavin, Daniel P.; Lazcano, Antonio

    2010-01-01

    Original extracts from an unpublished 1958 experiment conducted by the late Stanley L. Miller were recently found and analyzed using modern state-of-the-art analytical methods. The extracts were produced by the action of an electric discharge on a mixture of methane (CH4), hydrogen sulfide (H2S), ammonia (NH3), and carbon dioxide (CO2). Racemic methionine was farmed in significant yields, together with other sulfur-bearing organic compounds. The formation of methionine and other compounds from a model prebiotic atmosphere that contained H2S suggests that this type of synthesis is robust under reducing conditions, which may have existed either in the global primitive atmosphere or in localized volcanic environments on the early Earth. The presence of a wide array of sulfur-containing organic compounds produced by the decomposition of methionine and cysteine indicates that in addition to abiotic synthetic processes, degradation of organic compounds on the primordial Earth could have been important in diversifying the inventory of molecules of biochemical significance not readily formed from other abiotic reactions, or derived from extraterrestrial delivery.

  20. Prebiotic Synthesis of Methionine and Other Sulfur-Containing Organic Compounds on the Primitive Earth: A Contemporary Reassessment Based on an Unpublished 1958 Stanley Miller Experiment

    NASA Astrophysics Data System (ADS)

    Parker, Eric T.; Cleaves, H. James; Callahan, Michael P.; Dworkin, Jason P.; Glavin, Daniel P.; Lazcano, Antonio; Bada, Jeffrey L.

    2011-06-01

    Original extracts from an unpublished 1958 experiment conducted by the late Stanley L. Miller were recently found and analyzed using modern state-of-the-art analytical methods. The extracts were produced by the action of an electric discharge on a mixture of methane (CH4), hydrogen sulfide (H2S), ammonia (NH3), and carbon dioxide (CO2). Racemic methionine was formed in significant yields, together with other sulfur-bearing organic compounds. The formation of methionine and other compounds from a model prebiotic atmosphere that contained H2S suggests that this type of synthesis is robust under reducing conditions, which may have existed either in the global primitive atmosphere or in localized volcanic environments on the early Earth. The presence of a wide array of sulfur-containing organic compounds produced by the decomposition of methionine and cysteine indicates that in addition to abiotic synthetic processes, degradation of organic compounds on the primordial Earth could have been important in diversifying the inventory of molecules of biochemical significance not readily formed from other abiotic reactions, or derived from extraterrestrial delivery.

  1. Radiolysis of Sulfuric Acid, Sulfuric Acid Monohydrate, and Sulfuric Acid Tetrahydrate and Its Relevance to Europa

    NASA Technical Reports Server (NTRS)

    Loeffler, M. J.; Hudson, R. L.; Moore, M. H.; Carlson, R. W.

    2011-01-01

    We report laboratory studies on the 0.8 MeV proton irradiation of ices composed of sulfuric acid (H2SO4), sulfuric acid monohydrate (H2SO4 H2O), and sulfuric acid tetrahydrate (H2SO4 4H2O) between 10 and 180 K. Using infrared spectroscopy, we identify the main radiation products as H2O, SO2, (S2O3)x, H3O+, HSO4(exp -), and SO4(exp 2-). At high radiation doses, we find that H2SO4 molecules are destroyed completely and that H2SO4 H2O is formed on subsequent warming. This hydrate is significantly more stable to radiolytic destruction than pure H2SO4, falling to an equilibrium relative abundance of 50% of its original value on prolonged irradiation. Unlike either pure H2SO4 or H2SO4 H2O, the loss of H2SO4 4H2O exhibits a strong temperature dependence, as the tetrahydrate is essentially unchanged at the highest irradiation temperatures and completely destroyed at the lowest ones, which we speculate is due to a combination of radiolytic destruction and amorphization. Furthermore, at the lower temperatures it is clear that irradiation causes the tetrahydrate spectrum to transition to one that closely resembles the monohydrate spectrum. Extrapolating our results to Europa s surface, we speculate that the variations in SO2 concentrations observed in the chaotic terrains are a result of radiation processing of lower hydration states of sulfuric acid and that the monohydrate will remain stable on the surface over geological times, while the tetrahydrate will remain stable in the warmer regions but be destroyed in the colder regions, unless it can be reformed by other processes, such as thermal reactions induced by diurnal cycling.

  2. The role of sulfate reduction in longterm accumulation of organic and inorganic sulfur in lake sediments

    Microsoft Academic Search

    JOHN W. M. RUDD; C. A. KELLY; AKIRA FURUTANI

    1986-01-01

    Sulfate reduction and the accumulation of reduced sulfur in epilimnetic sediments were studied in lakes in southern Norway, the Adirondack Mountains, and at the Experimental Lakes Area (ELA) of northwestern Ontario. In all of the lakes, in addition to the previously known formation of acid volatile sulfur, sulfate reduction also produced substantial quantities of pyrite and organic sulfur compounds. In

  3. AN EXPERIMENTAL APPROACH OF ELEMENTAL SULFUR DEPOSITION IN CARBONATE OIL RESERVOIRS

    Microsoft Academic Search

    Shedid A. Shedid; Abdulrazag A. Zekri

    2002-01-01

    The existence of sulfur compounds in crude oils creates many problems of sulfur deposition in the vicinity of the wellbore hole, in well completion and\\/or production equipment, and in producing reservoir rocks. The major objectives of this experimental study are to investigate the influences of oil flow rate, initial sulfur concentration of crude oil, and reservoir rock permeability on elemental

  4. Refining a complex nickel alloy to remove a sulfur impurity during vacuum induction melting: Part II

    NASA Astrophysics Data System (ADS)

    Sidorov, V. V.; Min, P. G.

    2014-12-01

    The results of studying the refining of complexly alloyed nickel melts from sulfur during melting in a vacuum induction furnace or with the use of an oxide calcium crucible, metallic calcium added to a melt, or rare-earth metals additions (which form thermodynamically stable refractory compounds with sulfur and, thus, eliminate the harmful effect of sulfur in the alloys) are reported.

  5. Extending the models for iron and sulfur oxidation in the extreme Acidophile Acidithiobacillus ferrooxidans

    Microsoft Academic Search

    Raquel Quatrini; Corinne Appia-Ayme; Yann Denis; Eugenia Jedlicki; David S. Holmes; Violaine Bonnefoy

    2009-01-01

    BACKGROUND: Acidithiobacillus ferrooxidans gains energy from the oxidation of ferrous iron and various reduced inorganic sulfur compounds at very acidic pH. Although an initial model for the electron pathways involved in iron oxidation has been developed, much less is known about the sulfur oxidation in this microorganism. In addition, what has been reported for both iron and sulfur oxidation has

  6. SEMI-BATCH PRECIPITATION OF CALCIUM SULFATE DIHYDRATE FROM CALCITE AND SULFURIC ACID

    E-print Network

    Paris-Sud XI, Université de

    SEMI-BATCH PRECIPITATION OF CALCIUM SULFATE DIHYDRATE FROM CALCITE AND SULFURIC ACID Frédéric BARD1 a calcite suspension to a sulfuric acid solution from industrial waste. The morphology of the precipitated, sulfuric acid, industrial waste. 1. INTRODUCTION Gypsum is a mineral compound of first importance

  7. Cleavage of the Carbon-Sulfur Bonds in Thiophenes by a Binuclear Ruthenium Complex

    E-print Network

    Jones, William D.

    Notes Cleavage of the Carbon-Sulfur Bonds in Thiophenes by a Binuclear Ruthenium Complex William D Hydrodesulfurization is the industrial process in which sulfur is removed from organosulfur compounds found metal complexes serve as particularly appropriate models for studying the binding modes of sulfur

  8. Surface Science 415 (1998) 2936 Structural studies of sulfur-passivated GaAs (100)

    E-print Network

    Zhang, Yanchao

    Surface Science 415 (1998) 29­36 Structural studies of sulfur-passivated GaAs (100) surfaces) and atomic force microscopy (AFM) analysis of sulfur-passivating layers on the GaAs (100) surface. The Ga-based compounds. We prepared the inorganic sulfur-passivated GaAs(100) surfaces with a wet chemical treatment

  9. ONBOARD SVM ANALYSIS OF HYPERION DATA TO DETECT SULFUR DEPOSITS IN ARCTIC REGIONS

    E-print Network

    Schaffer, Steven

    ONBOARD SVM ANALYSIS OF HYPERION DATA TO DETECT SULFUR DEPOSITS IN ARCTIC REGIONS Lukas Mandrake(1 interaction. In this study, we observe the sulfur-rich Borup-Fiord glacial springs in Canada with the Hyperion to autonomously identify the presence of sulfur compounds associated with the activity of microbial life. However

  10. Performance of Sulfur Tolerant Reforming Catalysts for Production of Hydrogen from Jet Fuel Simulants

    E-print Network

    Azad, Abdul-Majeed

    Performance of Sulfur Tolerant Reforming Catalysts for Production of Hydrogen from Jet Fuel and military applications. The presence of high concentrations of sulfur-containing organic compounds leads to rapid deactivation of traditional reforming catalysts, and removal of the sulfur components from

  11. ICoN2 and the NCycle16 1859 Dissimilatory sulfur cycling in oxygen minimum

    E-print Network

    Stewart, Frank

    ICoN2 and the NCycle16 1859 Dissimilatory sulfur cycling in oxygen minimum zones: an emerging confirm that OMZs also support diverse micro-organisms capable of utilizing inorganic sulfur compounds to identify the molecular basis for autotrophic sulfur oxidation with nitrate in the OMZ water column, as well

  12. Ectothiorhodospira mobilis Pelsh, a Photosynthetic Sulfur Bacterium Depositing Sulfur Outside the Cells1

    PubMed Central

    Trüper, Hans G.

    1968-01-01

    From salt flats on the Galapagos Islands, two strains of a red photosynthetic bacterium were isolated and identified as Ectothiorhodospira mobilis, an organism first described by Pelsh in 1937. The cells are curved in a short spiral, 0.7 to 1.0 ? wide and 2.0 to 4.8 ? long. They are motile by a polar tuft of flagella. Cells contain several large stacks of lamellar membranes, carrying the pigments bacteriochlorophyll a and carotenoids of the spirillo xanthin series. Cell division occurs by binary fission, not budding. The organism is strictly anaerobic and obligately photosynthetic. Its ability to grow well with sulfide, sulfur, thiosulfate, or sulfite as photosynthetic H donors puts it taxonomically in the Thiorhodaceae. During growth with sulfide, elementary sulfur is deposited outside the cells in the medium and disappears during further growth. A limited number of organic carbon compounds can be utilized as hydrogen donors in place of inorganic sulfur compounds. Under these conditions, sulfate can serve as the sulfur source. The enzymes catalase and hydrogenase are present. The newly isolated strains require vitamin B12. They also require a salinity of 2 to 3% NaCl, but they are not extreme halophiles. The organism is not identical with any of the species listed in Bergey's Manual. Images PMID:5650091

  13. Missing SO2 oxidant in the coastal atmosphere? - observations from high-resolution measurements of OH and atmospheric sulfur compounds

    NASA Astrophysics Data System (ADS)

    Berresheim, H.; Adam, M.; Monahan, C.; O'Dowd, C.; Plane, J. M. C.; Bohn, B.; Rohrer, F.

    2014-11-01

    Diurnal and seasonal variations of gaseous sulfuric acid (H2SO4) and methane sulfonic acid (MSA) were measured in NE Atlantic air at the Mace Head atmospheric research station during the years 2010 and 2011. The measurements utilized selected-ion chemical ionization mass spectrometry (SI/CIMS) with a detection limit for both compounds of 4.3 × 104 cm-3 at 5 min signal integration. The H2SO4 and MSA gas-phase concentrations were analyzed in conjunction with the condensational sink for both compounds derived from 3 nm to 10 ?m (aerodynamic diameter) aerosol size distributions. Accommodation coefficients of 1.0 for H2SO4 and 0.12 for MSA were assumed, leading to estimated atmospheric lifetimes on the order of 7 and 25 min, respectively. With the SI/CIMS instrument in OH measurement mode alternating between OH signal and background (non-OH) signal, evidence was obtained for the presence of one or more unknown oxidants of SO2 in addition to OH. Depending on the nature of the oxidant(s), its ambient concentration may be enhanced in the CIMS inlet system by additional production. The apparent unknown SO2 oxidant was additionally confirmed by direct measurements of SO2 in conjunction with calculated H2SO4 concentrations. The calculated H2SO4 concentrations were consistently lower than the measured concentrations by a factor of 4.7 ± 2.4 when considering the oxidation of SO2 by OH as the only source of H2SO4. Both the OH and the background signal were also observed to increase significantly during daytime aerosol nucleation events, independent of the ozone photolysis frequency, J(O1D), and were followed by peaks in both H2SO4 and MSA concentrations. This suggests a strong relation between the unknown oxidant(s), OH chemistry, and the atmospheric photolysis and photooxidation of biogenic iodine compounds. As to the identity of the atmospheric SO2 oxidant(s), we have been able to exclude ClO, BrO, IO, and OIO as possible candidates based on {ab initio} calculations. Nevertheless, IO could contribute significantly to the observed CIMS background signal. A detailed analysis of this CIMS background signal in context with recently published kinetic data currently suggests that Criegee intermediates (CIs) produced from ozonolysis of alkenes play no significant role for SO2 oxidation in the marine atmosphere at Mace Head. On the other hand, SO2 oxidation by small CIs such as CH2OO produced photolytically or possibly in the photochemical degradation of methane is consistent with our observations. In addition, H2SO4 formation from dimethyl sulfide oxidation via SO3 as an intermediate instead of SO2 also appears to be a viable explanation. Both pathways need to be further explored.

  14. Sulfur and Hydrogen Isotope Anomalies in Meteorite Sulfonic Acids

    NASA Technical Reports Server (NTRS)

    Cooper, George W.; Thiemens, Mark H.; Jackson, Teresa L.; Chang, Sherwood

    1997-01-01

    Intramolecular carbon, hydrogen, and sulfur isotope ratios were measured on a homologous series of organic sulfonic acids discovered in the Murchison meteorite. Mass-independent sulfur isotope fractionations were observed along with high deuterium/hydrogen ratios. The deuterium enrichments indicate formation of the hydrocarbon portion of these compounds in a low-temperature environment that is consistent with that of interstellar clouds. Sulfur-33 enrichments observed in methanesulfonic acid could have resulted from gas-phase ultraviolet irradiation of a precursor, carbon disulfide. The source of the sulfonic acid precursors may have been the reactive interstellar molecule carbon monosulfide.

  15. Sulfur and Hydrogen Isotope Anomalies in Meteorite Sulfonic Acids

    NASA Astrophysics Data System (ADS)

    Cooper, George W.; Thiemens, Mark H.; Jackson, Teresa L.; Chang, Sherwood

    1997-08-01

    Intramolecular carbon, hydrogen, and sulfur isotope ratios were measured on a homologous series of organic sulfonic acids discovered in the Murchison meteorite. Mass-independent sulfur isotope fractionations were observed along with high deuterium/hydrogen ratios. The deuterium enrichments indicate formation of the hydrocarbon portion of these compounds in a low-temperature environment that is consistent with that of interstellar clouds. Sulfur-33 enrichments observed in methanesulfonic acid could have resulted from gas-phase ultraviolet irradiation of a precursor, carbon disulfide. The source of the sulfonic acid precursors may have been the reactive interstellar molecule carbon monosulfide.

  16. 40 CFR 52.1881 - Control strategy: Sulfur oxides (sulfur dioxide).

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...elemental sulfur, alkylation acid, hydrogen sulfide, organic sulfides and...of the stoichiometric amount of hydrogen peroxide absorbent. (ii) The test methods...total sulfur content expressed as hydrogen sulfide in excess of 350...

  17. 40 CFR 52.1881 - Control strategy: Sulfur oxides (sulfur dioxide).

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...elemental sulfur, alkylation acid, hydrogen sulfide, organic sulfides and...of the stoichiometric amount of hydrogen peroxide absorbent. (ii) The test methods...total sulfur content expressed as hydrogen sulfide in excess of 350...

  18. 40 CFR 52.1881 - Control strategy: Sulfur oxides (sulfur dioxide).

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...elemental sulfur, alkylation acid, hydrogen sulfide, organic sulfides and...of the stoichiometric amount of hydrogen peroxide absorbent. (ii) The test methods...total sulfur content expressed as hydrogen sulfide in excess of 350...

  19. 40 CFR 52.1881 - Control strategy: Sulfur oxides (sulfur dioxide).

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...elemental sulfur, alkylation acid, hydrogen sulfide, organic sulfides and...of the stoichiometric amount of hydrogen peroxide absorbent. (ii) The test methods...total sulfur content expressed as hydrogen sulfide in excess of 350...

  20. Ceramic-metal seals for advanced battery systems. [sodium sulfur and lithium sulfur batteries

    NASA Technical Reports Server (NTRS)

    Reed, L.

    1978-01-01

    The search for materials which are electrochemically compatible with the lithium sulfur and sodium sulfur systems is discussed. The use liquid or braze alloys, titanium hydrite coatings, and tungsten yttria for bonding beryllium with ceramic is examined.

  1. Contribution of isotopologue self-shielding to sulfur mass-independent fractionation during sulfur dioxide photolysis

    E-print Network

    Lyons, J. R.

    Signatures of sulfur mass-independent fractionation (S-MIF) are observed for sulfur minerals in Archean rocks, and for modern stratospheric sulfate aerosols (SSA) deposited in polar ice. Ultraviolet light photolysis of ...

  2. Introduction to Sulfur Metabolism in Phototrophic Organisms

    Microsoft Academic Search

    Christiane Dahl; Rüdiger Hell; Thomas Leustek; David Knaff

    Sulfur is one of the most versatile elements in life due to its reactivity in different oxidation and reduction states. In\\u000a phototrophic organisms, the redox properties of sulfur in proteins and of sulfur-containing metabolites are particularly important\\u000a for the mediation between the reductive assimilation processes of photosynthesis and reactive oxygen species that arise as\\u000a by-products of electron transport chains in

  3. HYDROCARBON AND SULFUR SENSORS FOR SOFC SYSTEMS

    SciTech Connect

    A.M. Azad; Chris Holt; Todd Lesousky; Scott Swartz

    2003-11-01

    The following report summarizes work conducted during the Phase I program Hydrocarbon and Sulfur Sensors for SOFC Systems under contract No. DE-FC26-02NT41576. For the SOFC application, sensors are required to monitor hydrocarbons and sulfur in order to increase the operation life of SOFC components. This report discusses the development of two such sensors, one based on thick film approach for sulfur monitoring and the second galvanic based for hydrocarbon monitoring.

  4. Sulfur Chemistry in Bacterial Leaching of Pyrite

    Microsoft Academic Search

    AXEL SCHIPPERS; PETER-GEORG JOZSA

    1996-01-01

    In the case of pyrite bioleaching byLeptospirillum ferrooxidans, an organism without sulfur-oxidizing capac- ity, besides the production of tetra- and pentathionate, a considerable accumulation of elemental sulfur occurred. A similar result was obtained for chemical oxidation assays with acidic, sterile iron(III) ion- containing solutions. In the case of Thiobacillus ferrooxidans, only slight amounts of elemental sulfur were detectablebecauseoftheorganism'scapacitytooxidizesulfurcompounds.Inthecourseofoxidative,chemical pyrite degradation

  5. Lithoheterotrophic growth and electron transfer chain components of the filamentous gliding bacterium Leucothrix mucor DSM 2157 during oxidation of sulfur compounds

    Microsoft Academic Search

    Margarita Yu. Grabovich; Maria S. Muntyan; Valentina Yu. Lebedeva; Vladimir S. Ustiyan; Galina A. Dubinina

    1999-01-01

    Evidence is presented that the type strain of filamentous gliding bacterium Leucothrix mucor DSM 2157 is capable of lithoheterotrophic growth. Thiosulfate oxidation was accompanied by accumulation of sulfate and tetrathionate in the growth medium and intracellular accumulation of elemental sulfur, as occurs in filamentous sulfur bacteria of the genus Thiothrix. Thiosulfate oxidation by L. mucor was induced during growth with

  6. Sulfurization of a carbon surface for vapor phase mercury removal – II: Sulfur forms and mercury uptake

    Microsoft Academic Search

    Wenguo Feng; Eric Borguet; Radisav D. Vidic

    2006-01-01

    Sulfur forms deposited on carbonaceous surfaces after exposure to hydrogen sulfide were analyzed using XPS and XANES. Higher temperatures promote the formation of organic sulfur and the presence of H2S during the cooling process increased elemental sulfur content. Temperatures between 400–600°C were found to be optimal for producing effective mercury uptake sorbents. The increased amount of sulfur deposited during the

  7. Sulfur: Not a Silent Element Any More!

    SciTech Connect

    Jalilehvand, F.

    2007-07-09

    To understand the many important functions of sulfur, a ubiquitous element in biological systems, in the environment and for industrial applications, detailed analyses are needed. Characterization of the variety of sulfur functional groups in a natural sample, often occurring in a wide range of oxidation states, became possible when the development of dedicated X-ray absorption near-edge structure (XANES) spectroscopy started in the mid-1980s. This tutorial review provides an overview of sulfur XANES spectroscopic investigations into the role of sulfur in all kinds of natural samples, from sediment and oil to marine-archaeological wood and plants.

  8. Are the clouds of Venus sulfuric acid.

    NASA Technical Reports Server (NTRS)

    Young, A. T.

    1973-01-01

    It is shown that strong aqueous sulfuric acid solutions have the right refractive index and freeze at Venusian cloud temperature, explain the dryness of the Venusian stratosphere, are consistent with some features of the Venusian IR spectrum, and do not absorb in highly reflecting areas of Venus. It is also indicated that such solutions should be produced by reactions between known atmospheric constituents and most sulfur-bearing rock at the Venusian surface temperature, and require only small amounts of sulfur consistent with its cosmic abundance and with the amounts of other volatile elements present in the atmosphere. It is believed therefore that the clouds of Venus consist of sulfuric acid solutions.

  9. Elemental sulfur in Eddy County, New Mexico

    USGS Publications Warehouse

    Hinds, Jim S.; Cunningham, Richard R.

    1970-01-01

    Sulfur has been reported in Eddy County, N. Mex., in rocks ranging from Silurian to Holocene in age at depths of 0-15,020 feet. Targets of present exploration are Permian formations in the Delaware Basin and northwest shelf areas at depths of less than 4,000 feet. Most of the reported sulfur occurrences in the shelf area are in the 'Abo' (as used by some subsurface geologists), Yeso, and San Andres Formations and the Artesia Group. Sulfur deposition in the dense dolomites of the 'Abo,' Yeso, and San Andres Formations is attributed to the reduction of ionic sulfate by hydrogen sulfide in formation waters in zones of preexisting porosity and permeability. A similar origin accounts for most of the sulfur deposits in the formations of the Artesia Group, but some of the sulfur in these formations may have originated in place through the alteration of anhydrite to carbonate and sulfur by the metabolic processes of bacteria in the presence of hydrocarbons. Exploration in the Delaware Basin area is directed primarily toward the Castile Formation. Sulfur deposits in the Castile Formation are found in irregular masses of cavernous brecciated secondary carbonate rock enveloped by impermeable anhydrite. The carbonate masses, or 'castiles,' probably originated as collapse features resulting from subsurface solution and upward stopping. Formation of carbonate rock and sulfur in the castiles is attributed to the reduction of brecciated anhydrite by bacteria and hydrocarbons in the same process ascribed to the formation of carbonate and sulfur in the caprocks of salt domes.

  10. biochemical reaction mechanisms in sulfur oxidation by chemosynthetic bacteria

    Microsoft Academic Search

    M. I. H. Aleem

    1975-01-01

    Summary  Aspects of the biochemistry of the oxidation of inorganic sulfur compounds are discussed in thiobacilli but chiefly inThiobacillus denitrificans. Almost all of the thiobacilli (e.g. T. denitrificans, T. neapolitanus, T. novellus, andThiobacillus A\\u000a 2) were capable of producing approximately 7.5 moles of sulfuric acid aerobically from 3.75 moles of thiosulfate per gram of\\u000a cellular protein per hr. By far the

  11. Massive atmospheric sulfur loading of the AD 1600 Huaynaputina eruption and implications for petrologic sulfur estimates

    E-print Network

    Paris-Sud XI, Université de

    Massive atmospheric sulfur loading of the AD 1600 Huaynaputina eruption and implications for petrologic sulfur estimates Fidel Costa1 and Bruno Scaillet Institut des Sciences de la Terre d'Orle´ans, UMR petrological, analytical, and thermodyna- mical data to constrain the sulfur yield of the AD 1600 Huaynaputina

  12. Binding mechanism of sulfur and dehydrogenated polyacrylonitrile in sulfur/polymer composite cathode

    NASA Astrophysics Data System (ADS)

    Doan, The Nam Long; Ghaznavi, Mahmoudreza; Zhao, Yan; Zhang, Yongguang; Konarov, Aishuak; Sadhu, Mikhail; Tangirala, Ravichandra; Chen, P.

    2013-11-01

    A composite consisting of sulfur/dehydrogenated polyacrylonitrile is one of the most promising cathode materials for use in rechargeable lithium-sulfur batteries. However, the reported sulfur contents have been low, less than 50 wt%, which compromise the intrinsic high specific capacity and energy of elemental sulfur and hence decrease significantly the specific energy of the composite. To identify the potential to further increase the sulfur content, we elucidate the binding mechanism of sulfur and polyacrylonitrile in their composite. The heat treatment experiments at varying timespans with excess sulfur showed a constancy of sulfur content after a critical length of timespan, indicating the saturation of sulfur in the structure of dehydrogenated polyacrylonitrile. Based on molecular structure and size consideration, it is proposed that the binding involves the formation of an 8 membered ring of sulfur embedded between 4 heterocyclic rings of dehydrogenated polyacrylonitrile. From this model and experimental results, we show that there exists an upper limit of sulfur content in the sulfur/dehydrogenated polyacrylonitrile composite at 56 wt%.

  13. Electron Collision Data: Sulfur Hexafluorine

    NSDL National Science Digital Library

    Tables of electron interaction cross sections, electron transport parameters, and information about references, uncertainties, and data needs regarding sulfur hexafluorine (SF-6) are provided here by the Electronics and Electronic Engineering Laboratory (EEEL) of the National Institute of Standards and Technology (NIST). These data come out of NIST's mission to provide a complete set of reliable electron collision data for gases used in the plasma processing of semiconductor devices. Along with the tables are color graphs of electron energy vs. cross section and electron transport coefficients for SF-6.

  14. Protocols for the selective cleavage of carbon-sulfur bonds in coal. Technical report, March 1, 1992May 30, 1992

    Microsoft Academic Search

    Bausch

    1992-01-01

    Chemical reactions that result in carbon-sulfur bond cleavage are an essential aspect of any protocol designed to remove organic sulfur from coal. Unfortunately, several classes of reactions that lead to carbon-sulfur bond cleavage are not well understood. Planned in ``Protocols for the Selective Cleavage of Carbon-Sulfur Bonds in Coal`` are reactions in which organic sulfur-containing coal model compounds are subjected

  15. Synthesis and structural elucidation of novel uranyl-crown ether compounds isolated from nitric, hydrochloric, sulfuric, and acetic acids

    Microsoft Academic Search

    Robin D. Rogers; Andrew H. Bond; William G. Hipple; Andrew N. Rollins; Rodger F. Henry

    1991-01-01

    The reactions of UOâSOâÃ3HâO with 12-crown-4, 15-crown-5, benzo-15-crown-5, 18-crown-6, and dibenzo-18-crown-6 were investigated in nitric, acetic, hydrochloric, and sulfuric acids. Impurities in the nitric acid resulted in the isolation of the complexes ((HâOâ)((NOâ)â benzo-15-crown-5)â)â((UOâ(NOâ)â)âCâOâ) (benzo-15-crown-5 was nitrated during the reaction) and ((HâO)(18-crown-6))â(UOâ(NOââ)âCâOâ), which were crystallographically characterized. (Mg(OHâ)â)((HâO)(15-crown-5))â((UOâ(SOâ))âCâOâ)â was also isolated from nitric acid and partially characterized crystallographically. Reactions in acetic

  16. Spectroscopic Detection and Structure of Hydroxidooxidosulfur (HOSO) Radical, an Important Intermediate in the Chemistry of Sulfur-Bearing Compounds

    NASA Astrophysics Data System (ADS)

    McCarthy, Michael C.; Lattanzi, Valerio; Martinez, Oscar, Jr.; Gauss, Jürgen; Thorwirth, Sven

    2013-11-01

    The rotational spectrum of hydroxidooxidosulfur, HOSO, an intermediate of particular interest in the combustion of sulfur-rich fuels, has been determined to high accuracy from gas-phase measurements. Detection of specific isotopic species using isotopically enriched gases suggests that HOSO is formed in our discharge nozzle via the reaction H + SO2 (+M) ? HOSO (+M). A precise experimental r0 geometry has also been derived from the isotopic analysis; HOSO has a cis configuration, but the subtle structural question of its planarity remains unresolved. From the derived spectroscopic constants, in situ and remote sensing for this fundamental radical can now be undertaken in a variety of environments, including in combustion reactors, the troposphere of Earth, and Io, the innermost Galilean moon of Jupiter.

  17. Graphene-wrapped sulfur nanospheres with ultra-high sulfur loading for high energy density lithium-sulfur batteries

    NASA Astrophysics Data System (ADS)

    Liu, Ya; Guo, Jinxin; Zhang, Jun; Su, Qingmei; Du, Gaohui

    2015-01-01

    Lithium-sulfur (Li-S) battery with high theoretical energy density is one of the most promising energy storage systems for electric vehicles and intermittent renewable energy. However, due to the poor conductivity of the active material, considerable weight of the electrode is occupied by the conductive additives. Here we report a graphene-wrapped sulfur nanospheres composite (S-nanosphere@G) with sulfur content up to 91 wt% as the high energy density cathode material for Li-S battery. The sulfur nanospheres with diameter of 400-500 nm are synthesized through a solution-based approach with the existence of polyvinylpyrrolidone (PVP). Then the sulfur nanospheres are uniformly wrapped by conductive graphene sheets through the electrostatic interaction between graphene oxide and PVP, followed by reducing of graphene oxide with hydrazine. The design of graphene wrapped sulfur nanoarchitecture provides flexible conductive graphene coating with void space to accommodate the volume expansion of sulfur and to minimize polysulfide dissolution. As a result, the S-nanosphere@G nanocomposite with 91 wt% sulfur shows a reversible initial capacity of 970 mA h g-1 and an average columbic efficiency > 96% over 100 cycles at a rate of 0.2 C. Taking the total mass of electrode into account, the S-nanosphere@G composite is a promising cathode material for high energy density Li-S batteries.

  18. The arbuscular mycorrhizal symbiosis influences sulfur starvation responses of Medicago truncatula.

    PubMed

    Sieh, Daniela; Watanabe, Mutsumi; Devers, Emanuel A; Brueckner, Franziska; Hoefgen, Rainer; Krajinski, Franziska

    2013-01-01

    Arbuscular mycorrhizal (AM) symbiosis is a mutualistic interaction that occurs between the large majority of vascular plants and fungi of the phylum Glomeromycota. In addition to other nutrients, sulfur compounds are symbiotically transferred from AM fungus to host plants; however, the physiological importance of mycorrhizal-mediated sulfur for plant metabolism has not yet been determined. We applied different sulfur and phosphate fertilization treatments to Medicago truncatula and investigated whether mycorrhizal colonization influences leaf metabolite composition and the expression of sulfur starvation-related genes. The expression pattern of sulfur starvation-related genes indicated reduced sulfur starvation responses in mycorrhizal plants grown at 1 mM phosphate nutrition. Leaf metabolite concentrations clearly showed that phosphate stress has a greater impact than sulfur stress on plant metabolism, with no demand for sulfur at strong phosphate starvation. However, when phosphate nutrition is high enough, mycorrhizal colonization reduces sulfur stress responses, probably as a result of symbiotic sulfur uptake. Mycorrhizal colonization is able to reduce sulfur starvation responses in M. truncatula when the plant's phosphate status is high enough that sulfur starvation is of physiological importance. This clearly shows the impact of mycorrhizal sulfur transfer on plant metabolism. PMID:23190168

  19. 40 CFR 52.2575 - Control strategy: Sulfur dioxide.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...2010-07-01 false Control strategy: Sulfur dioxide. 52.2575 Section 52.2575...Wisconsin § 52.2575 Control strategy: Sulfur dioxide. (a) Part D—Approval...the Administrator approved the Wisconsin sulfur dioxide control plan. (1) Part...

  20. 46 CFR 153.545 - Special requirements for liquid sulfur.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... false Special requirements for liquid sulfur. 153.545 Section 153.545 Shipping...153.545 Special requirements for liquid sulfur. (a) A containment system carrying liquid sulfur must have: (1) A cargo tank...

  1. 40 CFR 52.231 - Regulations: Sulfur oxides.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...2011-07-01 false Regulations: Sulfur oxides. 52.231 Section 52.231...California § 52.231 Regulations: Sulfur oxides. (a) [Reserved...National Ambient Air Quality Standard for Sulfur Oxides. (1) Lake County...

  2. 40 CFR 52.231 - Regulations: Sulfur oxides.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...2014-07-01 false Regulations: Sulfur oxides. 52.231 Section 52.231...California § 52.231 Regulations: Sulfur oxides. (a) [Reserved...National Ambient Air Quality Standard for Sulfur Oxides. (1) Lake County...

  3. 40 CFR 52.724 - Control strategy: Sulfur dioxide.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...2014-07-01 false Control strategy: Sulfur dioxide. 52.724 Section 52.724...Illinois> § 52.724 Control strategy: Sulfur dioxide. (a) Part D—Conditional...insure attainment and maintenance of the sulfur dioxide standard, and the...

  4. 40 CFR 52.795 - Control strategy: Sulfur dioxide.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...2014-07-01 false Control strategy: Sulfur dioxide. 52.795 Section 52.795...Indiana § 52.795 Control strategy: Sulfur dioxide. (a) Revised APC-13...Indiana's Air Pollution Control regulations (sulfur dioxide emission limitation) is...

  5. 40 CFR 52.231 - Regulations: Sulfur oxides.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...2010-07-01 false Regulations: Sulfur oxides. 52.231 Section 52.231...California § 52.231 Regulations: Sulfur oxides. (a) [Reserved...National Ambient Air Quality Standard for Sulfur Oxides. (1) Lake County...

  6. 40 CFR 52.795 - Control strategy: Sulfur dioxide.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...2011-07-01 false Control strategy: Sulfur dioxide. 52.795 Section 52.795...Indiana § 52.795 Control strategy: Sulfur dioxide. (a) Revised APC-13...Indiana's Air Pollution Control regulations (sulfur dioxide emission limitation) is...

  7. 40 CFR 52.795 - Control strategy: Sulfur dioxide.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...2010-07-01 false Control strategy: Sulfur dioxide. 52.795 Section 52.795...Indiana § 52.795 Control strategy: Sulfur dioxide. (a) Revised APC-13...Indiana's Air Pollution Control regulations (sulfur dioxide emission limitation) is...

  8. 40 CFR 52.2575 - Control strategy: Sulfur dioxide.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...2012-07-01 false Control strategy: Sulfur dioxide. 52.2575 Section 52.2575...Wisconsin § 52.2575 Control strategy: Sulfur dioxide. (a) Part D—Approval...the Administrator approved the Wisconsin sulfur dioxide control plan. (1) Part...

  9. 46 CFR 153.545 - Special requirements for liquid sulfur.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... false Special requirements for liquid sulfur. 153.545 Section 153.545 Shipping...153.545 Special requirements for liquid sulfur. (a) A containment system carrying liquid sulfur must have: (1) A cargo tank...

  10. 40 CFR 52.1030 - Control strategy: Sulfur oxides.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...2011-07-01 false Control strategy: Sulfur oxides. 52.1030 Section 52... § 52.1030 Control strategy: Sulfur oxides. (a) The revision to Regulation 100.6 (Chapter 106) “Low Sulfur Fuel Regulation” for the...

  11. 40 CFR 180.444 - Sulfur dioxide; tolerances for residues.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...2014-07-01 2014-07-01 false Sulfur dioxide; tolerances for residues. ...Specific Tolerances § 180.444 Sulfur dioxide; tolerances for residues. ...follows for sulfite residues of the fungicide sulfur dioxide (determined as (SO2 ))...

  12. Transport and equilibrium in molecular plasmas: the sulfur lamp

    E-print Network

    Eindhoven, Technische Universiteit

    Transport and equilibrium in molecular plasmas: the sulfur lamp PROEFSCHRIFT ter verkrijging van de William Transport and equilibrium in molecular plasmas: the sulfur lamp / by Colin William Johnston. : plasma / zwavel lamp / moleculen / transporteigenschappen Subject headings : plasma / sulfur lamp

  13. 40 CFR 52.724 - Control strategy: Sulfur dioxide.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...2011-07-01 false Control strategy: Sulfur dioxide. 52.724 Section 52.724...Illinois> § 52.724 Control strategy: Sulfur dioxide. (a) Part D—Conditional...insure attainment and maintenance of the sulfur dioxide standard, and the...

  14. 40 CFR 180.444 - Sulfur dioxide; tolerances for residues.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...2013-07-01 2013-07-01 false Sulfur dioxide; tolerances for residues. ...Specific Tolerances § 180.444 Sulfur dioxide; tolerances for residues. ...follows for sulfite residues of the fungicide sulfur dioxide (determined as (SO2 ))...

  15. 40 CFR 52.2575 - Control strategy: Sulfur dioxide.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...2014-07-01 false Control strategy: Sulfur dioxide. 52.2575 Section 52.2575...Wisconsin § 52.2575 Control strategy: Sulfur dioxide. (a) Part D—Approval...the Administrator approved the Wisconsin sulfur dioxide control plan. (1) Part...

  16. 46 CFR 153.545 - Special requirements for liquid sulfur.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... false Special requirements for liquid sulfur. 153.545 Section 153.545 Shipping...153.545 Special requirements for liquid sulfur. (a) A containment system carrying liquid sulfur must have: (1) A cargo tank...

  17. 40 CFR 180.444 - Sulfur dioxide; tolerances for residues.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...2010-07-01 2010-07-01 false Sulfur dioxide; tolerances for residues. ...Specific Tolerances § 180.444 Sulfur dioxide; tolerances for residues. ...follows for sulfite residues of the fungicide sulfur dioxide (determined as (SO2 ))...

  18. 40 CFR 52.231 - Regulations: Sulfur oxides.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...2013-07-01 false Regulations: Sulfur oxides. 52.231 Section 52.231...California § 52.231 Regulations: Sulfur oxides. (a) [Reserved...National Ambient Air Quality Standard for Sulfur Oxides. (1) Lake County...

  19. 46 CFR 153.545 - Special requirements for liquid sulfur.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... false Special requirements for liquid sulfur. 153.545 Section 153.545 Shipping...153.545 Special requirements for liquid sulfur. (a) A containment system carrying liquid sulfur must have: (1) A cargo tank...

  20. 40 CFR 180.444 - Sulfur dioxide; tolerances for residues.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...2011-07-01 2011-07-01 false Sulfur dioxide; tolerances for residues. ...Specific Tolerances § 180.444 Sulfur dioxide; tolerances for residues. ...follows for sulfite residues of the fungicide sulfur dioxide (determined as (SO2 ))...

  1. 40 CFR 52.231 - Regulations: Sulfur oxides.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...2012-07-01 false Regulations: Sulfur oxides. 52.231 Section 52.231...California § 52.231 Regulations: Sulfur oxides. (a) [Reserved...National Ambient Air Quality Standard for Sulfur Oxides. (1) Lake County...

  2. 40 CFR 52.795 - Control strategy: Sulfur dioxide.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...2013-07-01 false Control strategy: Sulfur dioxide. 52.795 Section 52.795...Indiana § 52.795 Control strategy: Sulfur dioxide. (a) Revised APC-13...Indiana's Air Pollution Control regulations (sulfur dioxide emission limitation) is...

  3. 40 CFR 52.2575 - Control strategy: Sulfur dioxide.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...2011-07-01 false Control strategy: Sulfur dioxide. 52.2575 Section 52.2575...Wisconsin § 52.2575 Control strategy: Sulfur dioxide. (a) Part D—Approval...the Administrator approved the Wisconsin sulfur dioxide control plan. (1) Part...

  4. 46 CFR 153.545 - Special requirements for liquid sulfur.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... false Special requirements for liquid sulfur. 153.545 Section 153.545 Shipping...153.545 Special requirements for liquid sulfur. (a) A containment system carrying liquid sulfur must have: (1) A cargo tank...

  5. 40 CFR 52.724 - Control strategy: Sulfur dioxide.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...2012-07-01 false Control strategy: Sulfur dioxide. 52.724 Section 52.724...Illinois> § 52.724 Control strategy: Sulfur dioxide. (a) Part D—Conditional...insure attainment and maintenance of the sulfur dioxide standard, and the...

  6. 40 CFR 52.795 - Control strategy: Sulfur dioxide.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...2012-07-01 false Control strategy: Sulfur dioxide. 52.795 Section 52.795...Indiana § 52.795 Control strategy: Sulfur dioxide. (a) Revised APC-13...Indiana's Air Pollution Control regulations (sulfur dioxide emission limitation) is...

  7. 40 CFR 52.1030 - Control strategy: Sulfur oxides.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...2013-07-01 false Control strategy: Sulfur oxides. 52.1030 Section 52... § 52.1030 Control strategy: Sulfur oxides. (a) The revision to Regulation 100.6 (Chapter 106) “Low Sulfur Fuel Regulation” for the...

  8. 40 CFR 180.444 - Sulfur dioxide; tolerances for residues.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...2012-07-01 2012-07-01 false Sulfur dioxide; tolerances for residues. ...Specific Tolerances § 180.444 Sulfur dioxide; tolerances for residues. ...follows for sulfite residues of the fungicide sulfur dioxide (determined as (SO2 ))...

  9. 40 CFR 52.2575 - Control strategy: Sulfur dioxide.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...2013-07-01 false Control strategy: Sulfur dioxide. 52.2575 Section 52.2575...Wisconsin § 52.2575 Control strategy: Sulfur dioxide. (a) Part D—Approval...the Administrator approved the Wisconsin sulfur dioxide control plan. (1) Part...

  10. 40 CFR 52.724 - Control strategy: Sulfur dioxide.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...2013-07-01 false Control strategy: Sulfur dioxide. 52.724 Section 52.724...Illinois> § 52.724 Control strategy: Sulfur dioxide. (a) Part D—Conditional...insure attainment and maintenance of the sulfur dioxide standard, and the...

  11. Sulfur metabolism in the extreme acidophile acidithiobacillus caldus.

    PubMed

    Mangold, Stefanie; Valdés, Jorge; Holmes, David S; Dopson, Mark

    2011-01-01

    Given the challenges to life at low pH, an analysis of inorganic sulfur compound (ISC) oxidation was initiated in the chemolithoautotrophic extremophile Acidithiobacillus caldus. A. caldus is able to metabolize elemental sulfur and a broad range of ISCs. It has been implicated in the production of environmentally damaging acidic solutions as well as participating in industrial bioleaching operations where it forms part of microbial consortia used for the recovery of metal ions. Based upon the recently published A. caldus type strain genome sequence, a bioinformatic reconstruction of elemental sulfur and ISC metabolism predicted genes included: sulfide-quinone reductase (sqr), tetrathionate hydrolase (tth), two sox gene clusters potentially involved in thiosulfate oxidation (soxABXYZ), sulfur oxygenase reductase (sor), and various electron transport components. RNA transcript profiles by semi quantitative reverse transcription PCR suggested up-regulation of sox genes in the presence of tetrathionate. Extensive gel based proteomic comparisons of total soluble and membrane enriched protein fractions during growth on elemental sulfur and tetrathionate identified differential protein levels from the two Sox clusters as well as several chaperone and stress proteins up-regulated in the presence of elemental sulfur. Proteomics results also suggested the involvement of heterodisulfide reductase (HdrABC) in A. caldus ISC metabolism. A putative new function of Hdr in acidophiles is discussed. Additional proteomic analysis evaluated protein expression differences between cells grown attached to solid, elemental sulfur versus planktonic cells. This study has provided insights into sulfur metabolism of this acidophilic chemolithotroph and gene expression during attachment to solid elemental sulfur. PMID:21687411

  12. Sulfur Metabolism in the Extreme Acidophile Acidithiobacillus Caldus

    PubMed Central

    Mangold, Stefanie; Valdés, Jorge; Holmes, David S.; Dopson, Mark

    2011-01-01

    Given the challenges to life at low pH, an analysis of inorganic sulfur compound (ISC) oxidation was initiated in the chemolithoautotrophic extremophile Acidithiobacillus caldus. A. caldus is able to metabolize elemental sulfur and a broad range of ISCs. It has been implicated in the production of environmentally damaging acidic solutions as well as participating in industrial bioleaching operations where it forms part of microbial consortia used for the recovery of metal ions. Based upon the recently published A. caldus type strain genome sequence, a bioinformatic reconstruction of elemental sulfur and ISC metabolism predicted genes included: sulfide–quinone reductase (sqr), tetrathionate hydrolase (tth), two sox gene clusters potentially involved in thiosulfate oxidation (soxABXYZ), sulfur oxygenase reductase (sor), and various electron transport components. RNA transcript profiles by semi quantitative reverse transcription PCR suggested up-regulation of sox genes in the presence of tetrathionate. Extensive gel based proteomic comparisons of total soluble and membrane enriched protein fractions during growth on elemental sulfur and tetrathionate identified differential protein levels from the two Sox clusters as well as several chaperone and stress proteins up-regulated in the presence of elemental sulfur. Proteomics results also suggested the involvement of heterodisulfide reductase (HdrABC) in A. caldus ISC metabolism. A putative new function of Hdr in acidophiles is discussed. Additional proteomic analysis evaluated protein expression differences between cells grown attached to solid, elemental sulfur versus planktonic cells. This study has provided insights into sulfur metabolism of this acidophilic chemolithotroph and gene expression during attachment to solid elemental sulfur. PMID:21687411

  13. Sulfur dioxide in geothermal waters and gases

    Microsoft Academic Search

    Stephen Zinder; Thomas D. Brock

    1977-01-01

    Methods were developed for stabilizing SO 2 in water and gas samples. The pararosaniline colorimetric method, and a gas Chromatographic method using a flame photometric detector specific for sulfur gases were used to assay SO 2 . Assays were also performed for sulfide, elemental sulfur and sulfate. A large number of acidic, neutral, and alkaline springs in Yellowstone National Park

  14. SURFACE REACTIONS OF OXIDES OF SULFUR

    EPA Science Inventory

    Surface reactions of several sulfur-containing molecules have been studied in order to understand the mechanism by which sulfate ions are formed on atmospheric aerosols. At 25C the heterogeneous oxidation of SO2 by NO2 to sulfuric acid and sulfate ions occurred on hydrated silica...

  15. Sulfur in Distillers Grains for Dairy Cattle

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Sulfur is an essential element needed by animals for many functions. About 0.15% of the body weight is sulfur. It is found in the amino acids methionine, cysteine, cystine, homocysteine, and taurine; in chondroitin sulfate of cartilage; and in the B-vitamins, thiamin and biotin. Methionine, thiam...

  16. Microbial Architecture of Environmental Sulfur Processes: A

    E-print Network

    Hitchcock, Adam P.

    potential impacts on water quality, including acid generation in acid mine drainage (AMD) environments, 2009. Accepted July 9, 2009. Microbial oxidation of sulfur-rich mining waste materials drives acid mine drainage (AMD) and affects the global sulfur biogeochemical cycle. The generation of AMD is a complex

  17. Sulfuric Acid and Water: Paradoxes of Dilution

    ERIC Educational Resources Information Center

    Leenson, I. A.

    2004-01-01

    On equilibrium properties of aqueous solutions of sulfuric acid, Julius Thomsen has marked that the heat evolved on diluting liquid sulfuric acid with water is a continuous function of the water used, and excluded absolutely the acceptance of definite hydrates as existing in the solution. Information about thermochemical measurement, a discussion…

  18. INTERNATIONAL SULFUR DEPOSITION MODEL EVALUATION (ISDME)

    EPA Science Inventory

    Eleven linear-chemistry atmospheric models of sulfur deposition were evaluated for each season of 1980. The evaluation data set consisted of sulfur wet deposition amounts calculated from screened precipitation chemistry measurements at 46 sites across eastern North America. The f...

  19. Stability of sulfur slopes on Io

    NASA Technical Reports Server (NTRS)

    Clow, G. D.; Carr, M. H.

    1980-01-01

    The mechanical properties of elemental sulfur are such that the upper crust of Io cannot be primarily sulfur. For heat flows in the range 100-1000 ergs/sq cm sec sulfur becomes ductile within several hundred meters of the surface and would prevent the formation of calderas with depths greater than this. However, the one caldera for which precise depth data are available is 2 km deep, and this value may be typical. A study of the mechanical equilibrium of simple slopes shows that the depth to the zone of rapid ductile flow strongly controls the maximum heights for sulfur slopes. Sulfur scarps with heights greater than 1 km will fail for all heat flows greater than 180 ergs/sq cm sec and slope angles greater than 22.5 deg. The observed relief on Io is inconsistent with that anticipated for a predominantly sulfur crust. However, a silicate crust with several percent sulfur included satisfies both the mechanical constraints and the observed presence of sulfur on Io.

  20. Sulfur oxide adsorbents and emissions control

    DOEpatents

    Li, Liyu (Richland, WA); King, David L. (Richland, WA)

    2006-12-26

    High capacity sulfur oxide absorbents utilizing manganese-based octahedral molecular sieve (Mn--OMS) materials are disclosed. An emissions reduction system for a combustion exhaust includes a scrubber 24 containing these high capacity sulfur oxide absorbents located upstream from a NOX filter 26 or particulate trap.

  1. Sulfuric acid leaching of Turkish chromite concentrate

    Microsoft Academic Search

    A. Geveci; Y. Topkaya; E. Ayhan

    2002-01-01

    In this work a high grade chromite concentrate obtained from Pinarbasi–Kayseri district of Turkey was reacted with a solution of sulfuric acid and perchloric acid. The effect of sulfuric acid concentration, temperature, duration, and perchloric acid addition on leach recovery was studied. At the end of leach reaction chromium appeared in the solution as Cr3+ and it did not change

  2. Isotopic composition and concentration of sulfur in carbonaceous chondrites

    NASA Technical Reports Server (NTRS)

    Gao, Xia; Thiemens, Mark H.

    1993-01-01

    New sulfur isotopic ratio measurements are reported for seven carbonaceous chondrites. Newly developed procedures permit measurement of delta S-33, delta S-34, and delta S-36 at precisions significantly greater than previously reported. A search for S-36 nucleosynthetic anomalies coproduced with anomalies in, for example, Ti-50 and Ca-48 was negative. The high endemic sulfur concentration probably dilutes any S-36 anomaly, and separation of individual sulfur phases may be needed to identify S-36 carrier phases. Large internal isotopic variations are observed, deriving from parent body and possibly nebular processes. Chondrule separates from Allende demonstrate isotopic compositions which vary as a function of diameter. High-temperature gas-solid exchange and a two-component mixing model may account for the observations. High-resolution isotopic data and structural information are reported for organic sulfur compounds separated by chemical extractions. The insoluble organics appear to be of either aliphatic or alicyclic structure and are dominant phases.

  3. Development of instrumental methods of analysis of sulfur compounds in coal process streams. Quarterly technical progress report for October-December 1980

    SciTech Connect

    Jordan, J.; Stutts, J. D.; Ankabrandt, S. J.; Stahl, J.; Yakupkovic, J. E.

    1981-01-01

    Work is in progress on the preparation of a user-oriented computer software manual, for estimating sulfur speciation in aqueous coal process streams form a thermodynamic data base. Capabilities and limitations of sulfide and polysulfide analysis by differential pulse polarography at a dropping mercury anode are assessed critically. Thallous nitrate used as the titrant reagent in a thermometric enthalpy titration yields the molar sum of monosulfide and polysulfide. Inorganic sulfur has been successfully speciated in coal conversion by-product water samples. A combination of differential pulse voltammetry, thermometric enthalpy titrations and classical methods was used. One hundred percent of the total sulfur present was quantitatively accounted for.

  4. The role of sulfur in detectingThe role of sulfur in detecting climate change on Venusclimate change on Venus

    E-print Network

    Treiman, Allan H.

    The role of sulfur in detectingThe role of sulfur in detecting climate change on Venusclimate: Progress, Prospects, and New Missions LPI Gilruth Center #12;Sulfur CyclesSulfur Cycles · Fast Atmospheric H2 + (1/n)Sn H2S CO + (1/n)Sn COS #12;Geologic Sulfur CycleGeologic Sulfur Cycle SO2 + 1/2O2 + CaCO3

  5. Sodium sulfur battery flight experiment definition study

    NASA Technical Reports Server (NTRS)

    Chang, Rebecca R.; Minck, Robert

    1989-01-01

    Sodium-sulfur batteries were identified as the most likely successor to nickel-hydrogen batteries for space applications. One advantage of the Na/S battery system is that the usable specific energy is two to three times that of nickel-hydrogen batteries. This represents a significant launch cost savings or increased payload mass capabilities. Sodium-sulfur batteries support NASA OAST's proposed Civil Space Technology Initiative goal of a factor of two improvement in spacecraft power system performance, as well as the proposed Spacecraft 2000 initiative. The sodium-sulfur battery operates at between 300 and 400 C, using liquid sodium and sulfur/polysulfide electrodes and solid ceramic electrolyte. The transport of the electrode materials to the surface of the electrolyte is through wicking/capillary forces. These critical transport functions must be demonstrated under actual microgravity conditions before sodium-sulfur batteries can be confidently utilized in space. Ford Aerospace Corporation, under contract to NASA Lewis Research Center, is currently working on the sodium-sulfur battery space flight experiment definition study. The objective is to design the experiment that will demonstrate operation of the sodium-sulfur battery/cell in the space environment with particular emphasis on evaluation of microgravity effects. Experimental payload definitions were completed and preliminary designs of the experiment were defined.

  6. Modeling total reduced sulfur and sulfur dioxide emissions from a kraft recovery boiler using an artificial neural network, and, Investigating volatile organic compounds in an urban intermountain valley using a TD/GC/MS methodology and intrinsic tracer molecules

    NASA Astrophysics Data System (ADS)

    Wrobel, Christopher Louis

    2000-11-01

    Back-propagation neural networks were trained to predict total reduced sulfur (TRS) and SO2 emissions from kraft recovery boiler operational data. A 0.721 coefficient of correlation was achieved between actual and predicted sulfur emissions on test data withheld from network training. The artificial neural network (ANN) models found an inverse, linear relationship between TRS/SO2 emissions and percent opacity. A number of relationships among operating parameters and sulfur emissions were identified by the ANN models. These relationships were used to formulate strategies for reducing sulfur emissions. Disagreement between ANN model predictions on a subsequent data set revealed an additional scenario for sulfur release not present in the training data. ANN modeling was demonstrated to be an effective tool for analyzing process variables when balancing productivity and environmental concerns. Five receptor sites distributed in the Missoula Valley, Montana, were employed to investigate possible VOC (benzene, 2,3,4-trimethylpentane, toluene, ethylbenzene, m-/p-xylene, o-xylene, naphthalene, acetone, chloroform, ?-pinene, ?-pinene, p-cymene and limonene) sources. The most dominant source of VOCs was found to be vehicle emissions. Furthermore, anthropogenic sources of terpenoids overwhelmed biogenic emissions, on a local scale. Difficulties correlating wind direction and pollutant levels could be explained by wind direction variability, low wind speed and seasonally dependent meteorological factors. Significant evidence was compiled to support the use of p-cymene as a tracer molecule for pulp mill VOC emissions. Apportionment techniques using o-xylene and p-cymene as tracers for automobile and pulp mill emissions, respectively, were employed to estimate each source's VOC contribution. Motor vehicles were estimated to contribute between 56 and 100 percent of the aromatic pollutants in the Missoula Valley airshed, depending upon the sampling location. Pulp mill emissions were estimated to account from 1 to 34 percent of the aromatic chemicals in the airshed. Measured ambient chloroform levels were attributable to the pulp mill (12-70%) and non-point source urban emissions (7.5-30%).

  7. Sulfur Recovery from Acid Gas Using the Claus Process and High Temperature Air Combustion (HiTAC) Technology

    Microsoft Academic Search

    Mohamed Sassi; Ashwani K. Gupta

    Sulfur-bearing compounds are very detrimental to the environment and to industrial process equipment. They are often obtained or formed as a by-product of separation and thermal processing of fuels containing sulfur, such as coal, crude oil and natural gas. The two sulfur compounds, which need special attention, are: hydrogen sulfide (H2S) and sulfur dioxide (SO2). H2S is a highly corrosive

  8. Catalyst for elemental sulfur recovery process

    DOEpatents

    Flytzani-Stephanopoulos, M.; Liu, W.

    1995-01-24

    A catalytic reduction process is described for the direct recovery of elemental sulfur from various SO[sub 2]-containing industrial gas streams. The catalytic process provides high activity and selectivity, as well as stability in the reaction atmosphere, for the reduction of SO[sub 2] to elemental sulfur product with carbon monoxide or other reducing gases. The reaction of sulfur dioxide and reducing gas takes place over a metal oxide composite catalyst having one of the following empirical formulas: [(FO[sub 2])[sub 1[minus]n](RO)[sub n

  9. Sulfur to nitrogen ratios in Ponderosa pine as bioindicators of foliar sulfur loading from air pollution

    SciTech Connect

    Johns, C.

    1984-01-01

    The objective of the research was to investigate the potential of foliar S:N ratios in Ponderosa pine as bioindicators of foliar sulfur loading in areas of long-term exposure to low levels of sulfurous air pollutants. First it was necessary to document seasonal variation in S:N ratios in trees not exposed to air pollution. Fifteen Ponderosa pines were selected at a site remote from urban and industrial sources of air pollution and the trees sampled at 18 intervals over a 15 month study period. Significant differences in sulfur and nitrogen concentrations occurred among the five needle age groups within most collections. One-year-old needles contained significantly more sulfur than other needles. Current-year needles contained more nitrogen than the three and four-year-old needles. Within each foliar age class significant differences in total sulfur content and S:N ratios occurred throughout the season. Sulfur concentrations and S:N r

  10. Large fractions of CO2-fixing microorganisms in pristine limestone aquifers appear to be involved in the oxidation of reduced sulfur and nitrogen compounds

    USGS Publications Warehouse

    Herrmann, Martina; Rusznyák, Anna; Akob, Denise M.; Schulze, Isabel; Opitz, Sebastian; Totsche, Kai Uwe; Küsel, Kirsten

    2015-01-01

    The traditional view of the dependency of subsurface environments on surface-derived allochthonous carbon inputs is challenged by increasing evidence for the role of lithoautotrophy in aquifer carbon flow. We linked information on autotrophy (Calvin-Benson-Bassham cycle) with that from total microbial community analysis in groundwater at two superimposed—upper and lower—limestone groundwater reservoirs (aquifers). Quantitative PCR revealed that up to 17% of the microbial population had the genetic potential to fix CO2 via the Calvin cycle, with abundances of cbbM and cbbL genes, encoding RubisCO (ribulose-1,5-bisphosphate carboxylase/oxygenase) forms I and II, ranging from 1.14 × 103 to 6 × 106 genes liter?1 over a 2-year period. The structure of the active microbial communities based on 16S rRNA transcripts differed between the two aquifers, with a larger fraction of heterotrophic, facultative anaerobic, soil-related groups in the oxygen-deficient upper aquifer. Most identified CO2-assimilating phylogenetic groups appeared to be involved in the oxidation of sulfur or nitrogen compounds and harbored both RubisCO forms I and II, allowing efficient CO2 fixation in environments with strong oxygen and CO2 fluctuations. The genera Sulfuricellaand Nitrosomonas were represented by read fractions of up to 78 and 33%, respectively, within the cbbM and cbbL transcript pool and accounted for 5.6 and 3.8% of 16S rRNA sequence reads, respectively, in the lower aquifer. Our results indicate that a large fraction of bacteria in pristine limestone aquifers has the genetic potential for autotrophic CO2 fixation, with energy most likely provided by the oxidation of reduced sulfur and nitrogen compounds.

  11. Effect of Non-Surgical Periodontal Therapy on the Concentration of Volatile Sulfur Compound in Mouth Air of a Group of Nigerian Young Adults

    PubMed Central

    Ehizele, AO; Akhionbare, O

    2013-01-01

    Background: The major goal of non-surgical periodontal therapy is to reduce or eliminate the subgingival pathogenic microbial flora that is known to be associated with volatile sulfur compounds (VSC). Aim: The aim of this study was, therefore, to determine the effect of non-surgical periodontal therapy on the concentration of VSC in mouth air of young adults. Subjects and Methods: Four hundred subjects, grouped into two based on the absence or presence of periodontal diseases, were involved in this study. Basic periodontal examination was used for the grouping. The measurement of the concentration of the VSC in the mouth air of the subjects was done objectively, using the Halimeter, before and after the therapy, and at recall visits 2 weeks and 6 weeks after therapy. Chi-square and Paired t-test were used to find statistical significance. Results: The results revealed that at baseline, 78.7% (48/61) of the subjects who had VSC concentration more than 250 parts per billion (ppb) were from the group with periodontal disease. Immediately after non-surgical periodontal therapy, only 8.5% (17/200) of the subjects with periodontal disease had VSC concentration of more than 250 ppb while all the subjects with no periodontal disease had VSC concentration less than 181 ppb. The same pattern of reduction in the concentration of the VSC and improvement in oral hygiene was also obtained 2 weeks and 6 weeks after therapy. Conclusion: It can be concluded that non-surgical periodontal therapy brought about reduction in the concentration of volatile sulfur compounds in mouth air of young adults. PMID:24116328

  12. Large Fractions of CO2-Fixing Microorganisms in Pristine Limestone Aquifers Appear To Be Involved in the Oxidation of Reduced Sulfur and Nitrogen Compounds.

    PubMed

    Herrmann, Martina; Rusznyák, Anna; Akob, Denise M; Schulze, Isabel; Opitz, Sebastian; Totsche, Kai Uwe; Küsel, Kirsten

    2015-04-01

    The traditional view of the dependency of subsurface environments on surface-derived allochthonous carbon inputs is challenged by increasing evidence for the role of lithoautotrophy in aquifer carbon flow. We linked information on autotrophy (Calvin-Benson-Bassham cycle) with that from total microbial community analysis in groundwater at two superimposed-upper and lower-limestone groundwater reservoirs (aquifers). Quantitative PCR revealed that up to 17% of the microbial population had the genetic potential to fix CO2 via the Calvin cycle, with abundances of cbbM and cbbL genes, encoding RubisCO (ribulose-1,5-bisphosphate carboxylase/oxygenase) forms I and II, ranging from 1.14 × 10(3) to 6 × 10(6) genes liter(-1) over a 2-year period. The structure of the active microbial communities based on 16S rRNA transcripts differed between the two aquifers, with a larger fraction of heterotrophic, facultative anaerobic, soil-related groups in the oxygen-deficient upper aquifer. Most identified CO2-assimilating phylogenetic groups appeared to be involved in the oxidation of sulfur or nitrogen compounds and harbored both RubisCO forms I and II, allowing efficient CO2 fixation in environments with strong oxygen and CO2 fluctuations. The genera Sulfuricella and Nitrosomonas were represented by read fractions of up to 78 and 33%, respectively, within the cbbM and cbbL transcript pool and accounted for 5.6 and 3.8% of 16S rRNA sequence reads, respectively, in the lower aquifer. Our results indicate that a large fraction of bacteria in pristine limestone aquifers has the genetic potential for autotrophic CO2 fixation, with energy most likely provided by the oxidation of reduced sulfur and nitrogen compounds. PMID:25616797

  13. CONSTRUCTION OF A PROTOTYPE SULFURIC ACID MIST MONITOR

    EPA Science Inventory

    A prototype sulfuric acid mist monitor has been constructed for the purpose of detecting sulfuric acid-sulfur trioxide. The monitor utilized the selective condensation method with subsequent determination of sulfuric acid by measuring the conductivity of an aqueous isopropanol so...

  14. 46 CFR 151.50-21 - Sulfuric acid.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ...5 2011-10-01 2011-10-01 false Sulfuric acid. 151.50-21 Section 151.50-21 Shipping...CARGOES Special Requirements § 151.50-21 Sulfuric acid. (a) How sulfuric acid may be carried. (1) Sulfuric acid...

  15. 46 CFR 151.50-21 - Sulfuric acid.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ...5 2014-10-01 2014-10-01 false Sulfuric acid. 151.50-21 Section 151.50-21 Shipping...CARGOES Special Requirements § 151.50-21 Sulfuric acid. (a) How sulfuric acid may be carried. (1) Sulfuric acid...

  16. 46 CFR 151.50-21 - Sulfuric acid.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ...5 2013-10-01 2013-10-01 false Sulfuric acid. 151.50-21 Section 151.50-21 Shipping...CARGOES Special Requirements § 151.50-21 Sulfuric acid. (a) How sulfuric acid may be carried. (1) Sulfuric acid...

  17. 46 CFR 151.50-21 - Sulfuric acid.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ...5 2012-10-01 2012-10-01 false Sulfuric acid. 151.50-21 Section 151.50-21 Shipping...CARGOES Special Requirements § 151.50-21 Sulfuric acid. (a) How sulfuric acid may be carried. (1) Sulfuric acid...

  18. 40 CFR 60.642 - Standards for sulfur dioxide.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...2013-07-01 false Standards for sulfur dioxide. 60.642 Section 60.642...23, 2011 § 60.642 Standards for sulfur dioxide. (a) During the initial...be determined from table 1 based on the sulfur feed rate (X) and the sulfur...

  19. Sulfur Dioxide Treatment from Flue Gases Using a Biotrickling

    E-print Network

    Sulfur Dioxide Treatment from Flue Gases Using a Biotrickling Filter-Bioreactor System L I G Y P H of California, Riverside, California 92521 Complete treatment of sulfur dioxide (SO2) from flue gases in a two effectively treat the biotrickling filter effluent and produce elemental sulfur. The sulfur production

  20. 40 CFR 60.642 - Standards for sulfur dioxide.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...2014-07-01 false Standards for sulfur dioxide. 60.642 Section 60.642...23, 2011 § 60.642 Standards for sulfur dioxide. (a) During the initial...be determined from table 1 based on the sulfur feed rate (X) and the sulfur...

  1. 40 CFR 60.642 - Standards for sulfur dioxide.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...2012-07-01 false Standards for sulfur dioxide. 60.642 Section 60.642...Emissions § 60.642 Standards for sulfur dioxide. (a) During the initial...be determined from table 1 based on the sulfur feed rate (X) and the sulfur...

  2. Sulfur isotope biogeochemistry of the Proterozoic McArthur Basin

    E-print Network

    Kaufman, Alan Jay

    Sulfur isotope biogeochemistry of the Proterozoic McArthur Basin David T. Johnston a,b,*, James such a scenario, we look to the structure of the biogeochemical sulfur cycle. We present sulfur (32 S, 33 S, 34 S of the Proterozoic ocean, highlight contributions from the oxidative sulfur cycle, and outline a new tool

  3. 40 CFR 60.642 - Standards for sulfur dioxide.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...2011-07-01 false Standards for sulfur dioxide. 60.642 Section 60.642...Emissions § 60.642 Standards for sulfur dioxide. (a) During the initial...be determined from table 1 based on the sulfur feed rate (X) and the sulfur...

  4. Separation techniques: sulfur recovery from low hydrogen sulfide gases

    Microsoft Academic Search

    Chute

    1982-01-01

    Processes are described for recovering sulfur from acid gases containing less HâS than can be processed satisfactorily in a typical Claus sulfur recovery unit. A previous work discussed several problems related to unusual conditions encountered in the design and operation of the modified Claus sulfur process for the conversion and recovery of elemental sulfur from gases containing HâS. Many of

  5. A Comparative Quantitative Proteomic Study Identifies New Proteins Relevant for Sulfur Oxidation in the Purple Sulfur Bacterium Allochromatium vinosum

    PubMed Central

    Weissgerber, Thomas; Sylvester, Marc; Kröninger, Lena

    2014-01-01

    In the present study, we compared the proteome response of Allochromatium vinosum when growing photoautotrophically in the presence of sulfide, thiosulfate, and elemental sulfur with the proteome response when the organism was growing photoheterotrophically on malate. Applying tandem mass tag analysis as well as two-dimensional (2D) PAGE, we detected 1,955 of the 3,302 predicted proteins by identification of at least two peptides (59.2%) and quantified 1,848 of the identified proteins. Altered relative protein amounts (?1.5-fold) were observed for 385 proteins, corresponding to 20.8% of the quantified A. vinosum proteome. A significant number of the proteins exhibiting strongly enhanced relative protein levels in the presence of reduced sulfur compounds are well documented essential players during oxidative sulfur metabolism, e.g., the dissimilatory sulfite reductase DsrAB. Changes in protein levels generally matched those observed for the respective relative mRNA levels in a previous study and allowed identification of new genes/proteins participating in oxidative sulfur metabolism. One gene cluster (hyd; Alvin_2036-Alvin_2040) and one hypothetical protein (Alvin_2107) exhibiting strong responses on both the transcriptome and proteome levels were chosen for gene inactivation and phenotypic analyses of the respective mutant strains, which verified the importance of the so-called Isp hydrogenase supercomplex for efficient oxidation of sulfide and a crucial role of Alvin_2107 for the oxidation of sulfur stored in sulfur globules to sulfite. In addition, we analyzed the sulfur globule proteome and identified a new sulfur globule protein (SgpD; Alvin_2515). PMID:24487535

  6. Process for the separation of sulfur oxides from a gaseous mixture containing sulfur oxides and oxygen

    SciTech Connect

    Derosset, A.J.; Ginger, E.A.

    1980-12-23

    An improved process for the separation of sulfur oxides from a gaseous mixture containing sulfur oxides and oxygen is disclosed. The gaseous mixture is contacted with a solid sulfur oxide acceptor comprising copper, copper oxide, or a mixture thereof dispersed on a carrier material in combination with a platinum group metal component and a component selected from the group consisting of rhenium, germanium and tin.

  7. Mass-independent sulfur of inclusions in diamond and sulfur recycling on early Earth.

    PubMed

    Farquhar, J; Wing, B A; McKeegan, K D; Harris, J W; Cartigny, P; Thiemens, M H

    2002-12-20

    Populations of sulfide inclusions in diamonds from the Orapa kimberlite pipe in the Kaapvaal-Zimbabwe craton, Botswana, preserve mass-independent sulfur isotope fractionations. The data indicate that material was transferred from the atmosphere to the mantle in the Archean. The data also imply that sulfur is not well mixed in the diamond source regions, allowing for reconstruction of the Archean sulfur cycle and possibly offering insight into the nature of mantle convection through time. PMID:12493909

  8. Improvement of cycle property of sulfur electrode for lithium\\/sulfur battery

    Microsoft Academic Search

    Young-Jin Choi; Ki-Won Kim; Hyo-Jun Ahn; Jou-Hyeon Ahn

    2008-01-01

    Although a theoretical specific capacity of lithium\\/sulfur redox couple battery is 1672mAh\\/g, lithium\\/sulfur battery has the serious problems of low utilization of active material and poor rechargeability, due to the loss of active material in the form of soluble polysulfides (Li2Sn, n>2). In this study, carbon nano-fiber having average fiber diameter of 150nm was added into the sulfur electrode in

  9. Desulfurization with transition-metal catalysts: scope and mechanism of cleaving carbon-sulfur bonds with subvalent nickel compounds. Final technical report, September 27, 1979September 26, 1981. [Desulfurization of dibenzothiophene, coal liquids benzylmercaptan, dibenzyl sulfide, dibenzyl disulfide

    Microsoft Academic Search

    Eisch

    1981-01-01

    Ongoing research in this author's laboratory has uncovered novel nickel(0) reagents that desulfurize dibenzothiophene, a common constituent of coal tar, in an homogeneous medium at temperatures below 100°. The first objective of this research was to make a thorough study of the mechanism and scope of this desulfurization, in which study a variety of organic sulfur compounds were examined and

  10. Analysis of sulfur in deposited aerosols by thermal decomposition and sulfur dioxide analyzer.

    PubMed

    Yamamoto, Masatoshi

    2005-07-15

    A thermal decomposition method that measures aerosol sulfur at the nanogram level directly from the collection substrate is described. A thermal decomposition apparatus was designed. A stainless steel strip was used as the aerosol collection substrate. A 0.1 mol/L MnCl2 solution was added as the thermal decomposition catalyst. Currents were passed through the strip where aerosol particles had been deposited. In this way, the strip was heated at 780 +/- 10 degrees C, and particulate sulfur was evaporated. A sulfur dioxide analyzer (SDA) with flame photometric detector (FPD) was used to detect gaseous sulfur. High sulfur recoveries from (NH4)2SO4 and other inorganic sulfates, such as NH4HSO4, K2SO4, MgSO4, and CaSO4, were obtained. From the sulfur blank and the calibration, a lower limited detection of 0.2 ng of sulfur and the determination range of 3.3-167 ng of sulfur were estimated. The method is effective for measuring the sulfate size distributions of urban aerosols in a small sample air volume of 50-60 L. The method is applicable to measuring the sulfur in aqueous extracts of size-segregated urban aerosols collected by impactor and comparing the results with the sulfate data measured by ion chromatography. PMID:16013855

  11. Definition of Non-Conventional Sulfur Utilization in Western Kazakhstan for Sulfur Concrete (Phase 1)

    SciTech Connect

    Kalb, Paul

    2007-05-31

    Battelle received a contract from Agip-KCO, on behalf a consortium of international oil and gas companies with exploration rights in the North Caspian Sea, Kazakhstan. The objective of the work was to identify and help develop new techniques for sulfur concrete products from waste, by-product sulfur that will be generated in large quantitites as drilling operations begin in the near future. BNL has significant expertise in the development and use of sulfur concrete products and has direct experience collaborating with the Russian and Kazakh partners that participated. Feasibility testing was successfully conducted for a new process to produce cost-effective sulfur polymer cement that has broad commerical applications.

  12. Sulfur Dioxide: Its Role in Climate Change

    NSDL National Science Digital Library

    2013-02-21

    In this problem-based learning activity, learners investigate impact of sulfur dioxide on the environment. Sulfur dioxide comes from both human activities and natural sources. Burning coal and other fossil fuels is the largest source of sulfur dioxide from human activities. Students have a choice of analyzing the impact of volcanoes’ emissions of sulfur dioxide on the environment; they can also investigate the idea of injecting sulfates into the atmosphere to counteract global warming. Instructions to access NASA data are provided along with additional resources and activities. This module was developed to be used in the Earth System Science Education Alliance (ESSEA) courses for middle and high school teachers and is also available to teachers to adapt for general classroom use.

  13. Identification of control parameters for the sulfur gas storability with bag sampling methods

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Air samples containing sulfur compounds are often collected and stored in sample bags prior to analyses. The storage stability of six gaseous sulfur compounds (H2S, CH3SH, DMS, CS2, DMDS and SO2) was compared between two different bag materials (polyvinyl fluoride (PVF) and polyester aluminum (PEA))...

  14. Effect of feeding distiller’s grains on reduced sulfur emissions

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Odorous reduced sulfur compounds are produced during manure decomposition and emitted from confined animal feeding operations. Feeding high-sulfur distiller’s byproducts may increase the emission of these compounds. The objectives of a series of feedlot pen studies was to (i) determine if emission...

  15. Sulfur removal and comminution of carbonaceous material

    SciTech Connect

    Narain, N.K.; Ruether, J.A.; Smith, D.N.

    1988-10-04

    A method is described of removing sulfur during the comminution of carbonaceous material comprising: forming a slurry including the carbonaceous material in aqueous, alkali-containing solution, increasing the temperature and pressure of the slurry to at least the critical temperature and pressure of steam; abruptly reducing the pressure to explosively comminute the carbonaceous material and release sulfur containing gases; separating the alkali from the comminuted carbonaceous material.

  16. Copper mercaptides as sulfur dioxide indicators

    DOEpatents

    Eller, Phillip G. (Los Alamos, NM); Kubas, Gregory J. (Los Alamos, NM)

    1979-01-01

    Organophosphine copper(I) mercaptide complexes are useful as convenient and semiquantitative visual sulfur dioxide gas indicators. The air-stable complexes form 1:1 adducts in the presence of low concentrations of sulfur dioxide gas, with an associated color change from nearly colorless to yellow-orange. The mercaptides are made by mixing stoichiometric amounts of the appropriate copper(I) mercaptide and phosphine in an inert organic solvent.

  17. Comparative genomics of green sulfur bacteria

    Microsoft Academic Search

    Colin Davenport; David W. Ussery; Burkhard Tümmler

    2010-01-01

    Eleven completely sequenced Chlorobi genomes were compared in oligonucleotide usage, gene contents, and synteny. The green sulfur bacteria (GSB) are equipped\\u000a with a core genome that sustains their anoxygenic phototrophic lifestyle by photosynthesis, sulfur oxidation, and CO2 fixation. Whole-genome gene family and single gene sequence comparisons yielded similar phylogenetic trees of the sequenced\\u000a chromosomes indicating a concerted vertical evolution of

  18. Biologically produced sulfur particles and polysulfide ions

    Microsoft Academic Search

    W. E. Kleinjan

    2005-01-01

    This thesis deals with the effects of particles of biologically produced sulfur (or 'biosulfur<\\/span>') on a biotechnological process for the removal of hydrogen sulfide from gas streams. Particular emphasis is given to the role of polysulfide ions in such a process. These polysulfide ions are formed from reaction of sulfide with biologically produced sulfur. The basic concepts of this

  19. Polymer Electrolytes for Lithium/Sulfur Batteries

    PubMed Central

    Zhao, Yan; Zhang, Yongguang; Gosselink, Denise; Doan, The Nam Long; Sadhu, Mikhail; Cheang, Ho-Jae; Chen, Pu

    2012-01-01

    This review evaluates the characteristics and advantages of employing polymer electrolytes in lithium/sulfur (Li/S) batteries. The main highlights of this study constitute detailed information on the advanced developments for solid polymer electrolytes and gel polymer electrolytes, used in the lithium/sulfur battery. This includes an in-depth analysis conducted on the preparation and electrochemical characteristics of the Li/S batteries based on these polymer electrolytes. PMID:24958296

  20. Atmospheric Influence of Earth's Earliest Sulfur Cycle

    Microsoft Academic Search

    James Farquhar; Huiming Bao; Mark Thiemens

    2000-01-01

    Mass-independent isotopic signatures for delta33S, delta34S, and delta36S from sulfide and sulfate in Precambrian rocks indicate that a change occurred in the sulfur cycle between 2090 and 2450 million years ago (Ma). Before 2450 Ma, the cycle was influenced by gas-phase atmospheric reactions. These atmospheric reactions also played a role in determining the oxidation state of sulfur, implying that atmospheric

  1. X-Ray Absorption Spectroscopy As a Probe of Microbial Sulfur Biochemistry: the Nature of Bacterial Sulfur Globules Revisited

    Microsoft Academic Search

    G. N. George; M. Gnida; D. A. Bazylinski; R. C. Prince; I. J. Pickering

    2009-01-01

    The chemical nature of the sulfur in bacterial sulfur globules has been the subject of controversy for a number of years. Sulfur K-edge X-ray absorption spectroscopy (XAS) is a powerful technique for probing the chemical forms of sulfur in situ, but two groups have used it with very different conclusions. The root of the controversy lies with the different detection

  2. X-Ray Absorption Spectroscopy as a Probe of Microbial Sulfur Biochemistry: the Nature of Bacterial Sulfur Globules Revisited

    Microsoft Academic Search

    Graham N. George; Manuel Gnida; Dennis A. Bazylinski; Roger C. Prince; Ingrid J. Pickering

    2008-01-01

    The chemical nature of the sulfur in bacterial sulfur globules has been the subject of controversy for a number of years. Sulfur K-edge X-ray absorption spectroscopy (XAS) is a powerful technique for probing the chemical forms of sulfur in situ, but two groups have used it with very different conclusions. The root of the controversy lies with the different detection

  3. Sulfur K-edge XANES Spectroscopy as a Tool for Understanding Sulfur Dynamics in Soil Organic Matter

    E-print Network

    Lehmann, Johannes

    Sulfur K-edge XANES Spectroscopy as a Tool for Understanding Sulfur Dynamics in Soil Organic Matter Dawit Solomon,* Johannes Lehmann, and Carmen Enid Marti´nez ABSTRACT in oxidation states. Sulfur occurs, form, and bio- and cultivated fields at Munesa sites in Ethiopia. Sulfur XANES geochemical

  4. Rapid determination of total sulfur in fuels using gas chromatography with atomic emission detection.

    PubMed

    Link, Dirk D; Baltrus, John P; Rothenberger, Kurt S; Zandhuis, Paul; Minus, Donald; Striebich, Richard C

    2002-10-01

    The purpose of this study is to determine whether gas chromatography (GC)-atomic emission detection (AED) can be used in a low-resolution mode for rapid, accurate determinations of total sulfur in fuels at trace levels to complement other popular methods of total sulfur analysis. A method for the rapid determination of total sulfur in fuels (called "fast GC-AED") is developed. The method is tested on gasoline, jet fuel, kerosene, and diesel fuel with sulfur concentrations ranging from 125 mg/L down to 2.5 mg/L. Fast GC-AED shows better performance than traditional GC-AED for total sulfur determinations, especially for complex mixtures containing many different sulfur-containing compounds at trace levels. This method also shows that GC-AED can be used for both rapid determinations of total sulfur and traditional determinations of speciated sulfur without requiring equipment changes. Fast GC-AED is competitive with other popular methods for sulfur analysis. The 5-min program that is developed for fast GC-AED is comparable with the time scale of other methods, such as wavelength dispersive X-ray fluorescence and UV-fluorescence (2 to 5 min). Fast GC-AED also compares favorably with UV-fluorescence for trace sulfur determinations, demonstrating accuracy down to 2.5-mg/L sulfur. PMID:12433111

  5. Process and apparatus for generating elemental sulfur and re-usable metal oxide from spent metal sulfide sorbents

    DOEpatents

    Ayala, Raul E. (Clifton Park, NY); Gal, Eli (Lititz, PA)

    1995-01-01

    A process and apparatus for generating elemental sulfur and re-usable metal oxide from spent metal-sulfur compound. Spent metal-sulfur compound is regenerated to re-usable metal oxide by moving a bed of spent metal-sulfur compound progressively through a single regeneration vessel having a first and second regeneration stage and a third cooling and purging stage. The regeneration is carried out and elemental sulfur is generated in the first stage by introducing a first gas of sulfur dioxide which contains oxygen at a concentration less than the stoichiometric amount required for complete oxidation of the spent metal-sulfur compound. A second gas containing sulfur dioxide and excess oxygen at a concentration sufficient for complete oxidation of the partially spent metal-sulfur compound, is introduced into the second regeneration stage. Gaseous sulfur formed in the first regeneration stage is removed prior to introducing the second gas into the second regeneration stage. An oxygen-containing gas is introduced into the third cooling and purging stage. Except for the gaseous sulfur removed from the first stage, the combined gases derived from the regeneration stages which are generally rich in sulfur dioxide and lean in oxygen, are removed from the regenerator as an off-gas and recycled as the first and second gas into the regenerator. Oxygen concentration is controlled by adding air, oxygen-enriched air or pure oxygen to the recycled off-gas.

  6. Homolytic bond dissociation energies for C-H bonds adjacent to sulfur and aromatic moieties: The effects of substituents of C-H bond strengths of the benzylic positions in coal model compounds

    SciTech Connect

    Alnajjar, M.S.; Franz, J.A. [Pacific Northwest Lab., Richland, WA (United States); Gleicher, G.J.; Truksa, S. [Oregon State Univ., Corvallis, OR (United States). Dept. of Chemistry; Bordwell, F.; Zhang, Xian-Man [Northwestern Univ., Evanston, IL (United States). Dept. of Chemistry

    1993-09-01

    Sulfur-containing compounds are precursors for thiyl radicals at coal liquefaction temperatures due to the weakness of The and S-S bonds. Thiyl radicals play important roles in hydrogen atom shuttling between benzylic positions and catalyze the cleavage and the formation of strong C-C bonds. Although many reactions of thiyl and other sulfur-containing radicals are qualitatively understood, the homolytic bond dissociation energies (EDE`s) and the thermochemistry associated with many key high molecular weight hydrocarbon and sulfur-containing organic structures important to coal is lacking because they are inappropriate for gas-phase techniques. The measurement of BDE`s has been proven to be difficult even in the simplest of molecules.

  7. Improved Chromatographic Techniques for Sulfur Pollutants

    NASA Technical Reports Server (NTRS)

    Hartmann, C. H.

    1971-01-01

    This paper describes several improvements in instrumental techniques for the analysis of low ppb concentrations of sulfur gases using gas chromatography (G.C.). This work has focused on the analytical problem of ambient air monitoring of the two main sulfur gas pollutants, hydrogen sulfide and sulfur dioxide. The most significant technical improvement that will be reported here is the newly developed silica gel column for ppb concentrations of the light sulfur gases (COS, H2S, CS2, SO2, CH3SH). A simplified inlet system will be described which improves reliability of the GC system. The flame photometric detector is used as the means of selectively and sensitively detecting the low concentrations of sulfur gases. Improvements will be described which have yielded better performance than previously reported for this application of the detector. Also included in this paper will be a report of field monitoring using this improved GC system. Reliability and repeatability of performance at the low ppb concentrations of sulfur gases will be demonstrated.

  8. The biology of reactive sulfur species (RSS).

    PubMed

    Gruhlke, Martin C H; Slusarenko, Alan J

    2012-10-01

    Sulfur is an essential and quantitatively important element for living organisms. Plants contain on average approximately 1 g S kg?¹ dry weight (for comparison plants contain approximately 15 g N kg?¹ dry weight). Sulfur is a constituent of many organic molecules, for example amino acids such as cysteine and methionine and the small tripeptide glutathione, but sulfur is also essential in the form of Fe-S clusters for the activity of many enzymes, particularly those involved in redox reactions. Sulfur chemistry is therefore important. In particular, sulfur in the form of thiol groups is central to manifold aspects of metabolism. Because thiol groups are oxidized and reduced easily and reversibly, the redox control of cellular metabolism has become an increasing focus of research. In the same way that oxygen and nitrogen have reactive species (ROS and RNS), sulfur too can form reactive molecular species (RSS), for example when a -SH group is oxidized. Indeed, several redox reactions occur via RSS intermediates. Several naturally occurring S-containing molecules are themselves RSS and because they are physiologically active they make up part of the intrinsic plant defence repertoire against herbivore and pathogen attack. Furthermore, RSS can also be used as redox-active pharmacological tools to study cell metabolism. The aim of this review is to familiarize the general reader with some of the chemical concepts, terminology and biology of selected RSS. PMID:22541352

  9. Sulfur "Concrete" for Lunar Applications - Sublimation Concerns

    NASA Technical Reports Server (NTRS)

    Grugel, Richard N.; Toutanji, Houssam

    2006-01-01

    Melting sulfur and mixing it with an aggregate to form "concrete" is commercially well established and constitutes a material that is particularly well-suited for use in corrosive environments. Discovery of the mineral troilite (FeS) on the moon poses the question of extracting the sulfur for use as a lunar construction material. This would be an attractive alternative to conventional concrete as it does not require water. However, the viability of sulfur concrete in a lunar environment, which is characterized by lack of an atmosphere and extreme temperatures, is not well understood. Here it is assumed that the lunar ore can be mined, refined, and the raw sulfur melded with appropriate lunar regolith to form, for example, bricks. This study evaluates pure sulfur and two sets of small sulfur concrete samples that have been prepared using JSC-1 lunar stimulant and SiO2 powder as aggregate additions. Each set was subjected to extended periods in a vacuum environment to evaluate sublimation issues. Results from these experiments are presented and discussed within the context of the lunar environment.

  10. Characterization of Sulfur in New York/New Jersey Waterway Sediment Ulrich Neuhusler, Huan Feng*, and Keith W. Jones**

    E-print Network

    Brookhaven National Laboratory

    Characterization of Sulfur in New York/New Jersey Waterway Sediment Ulrich Neuhäusler, Huan Feng. Sulfur plays an important role in the biogeochemical cycle of trace elements and in the diagenetic concern in the coastal and marine environment. In this study, we investigated sulfur compounds

  11. Feasibility of reconstructing paleoatmospheric records of selected alkanes, methyl halides, and sulfur gases from Greenland ice cores

    E-print Network

    Saltzman, Eric

    , and sulfur gases from Greenland ice cores M. Aydin,1 M. B. Williams,1 and E. S. Saltzman1 Received 7H6, and n-C4H10; two methyl halides, CH3Cl and CH3Br; and two sulfur compounds, OCS and CS2), Feasibility of reconstructing paleoatmospheric records of selected alkanes, methyl halides, and sulfur gases

  12. Experiments on ??34S mixing between organic and inorganic sulfur species during thermal maturation

    USGS Publications Warehouse

    Amrani, A.; Said-Ahamed, W.; Lewan, M.D.; Aizenshtat, Z.

    2006-01-01

    Reduced sulfur species were studied to constrain isotopic exchange-mixing with synthetic polysulfide cross-linked macromolecules (PCLM), model sulfur containing molecules and natural sulfur-rich kerogen, asphalt and oil of the Dead Sea area. PCLM represents protokerogens that are rich in sulfur and thermally unstable. Mixing rates of PCLM with HS-(aq) (added as (NH4)2S(aq)) at low to moderate temperatures (50-200 ??C) are rapid. Elemental sulfur and H2S(gas) fully mix isotopes with PCLM during pyrolysis conditions at 200 ??C. During these reactions significant structural changes of the PCLM occur to form polysulfide dimers, thiolanes and thiophenes. As pyrolysis temperatures or reaction times increase, the PCLM thermal products are transformed to more aromatic sulfur compounds. Isotopic mixing rates increase with increasing pyrolysis temperature and time. Polysulfide bonds (S-S) in the PCLM are responsible for most of these structural and isotopic changes because of their low stability. Conversely, sulfur isotope mixing does not occur between dibenzothiophene (aromatic S) or hexadecanthiol (C-SH) and HS-(aq) at 200 ??C after 48 h. This shows that rates of sulfur isotope mixing are strongly dependent on the functionality of the sulfur in the organic matter. The order of isotopic mixing rates for organic matter is kerogen > asphalt > oil, which is inverse to their sulfur thermal stability. Asphalt and oil with more refractory sulfur show significantly lower isotopes mixing rates than the kerogen with more labile sulfur. Based on the findings of the present study we suggest that sulfur isotopes mixing can occur from early diagenesis into catagenesis and result in isotopic homogenization of the inorganic and organic reduced sulfur pools. ?? 2006 Elsevier Inc. All rights reserved.

  13. Workshop on sulfur chemistry in flue gas desulfurization

    SciTech Connect

    Wallace, W.E. Jr.

    1980-05-01

    The Flue Gas Desulfurization Workshop was held at Morgantown, West Virginia, June 7-8, 1979. The presentations dealt with the chemistry of sulfur and calcium compounds in scrubbers. DOE and EPRI programs in this area are described. Ten papers have been entered individually into EDB and ERA. (LTN)

  14. Biotic and abiotic carbon to sulfur bond cleavage. Final report

    Microsoft Academic Search

    Frost

    1994-01-01

    The microbial desulfurization of organosulfur compounds occurs by unprecedented and largely unexplored biochemical processes. A study of such biotic desulfurizations can be expected to give rise to new and useful chemistry and enzymology. The potential value of understanding and harnessing these processes is seen in relation to the need for methods for the removal of organically bound sulfur from coal

  15. Modern applications for a total sulfur reduction distillation method - what’s old is new again

    PubMed Central

    2014-01-01

    Background The use of a boiling mixture of hydriodic acid, hypophosphorous acid, and hydrochloric acid to reduce any variety of sulfur compounds has been in use in various applications since the first appearance of this method in the literature in the 1920’s. In the realm of sulfur geochemistry, this method remains a useful, but under-utilized technique. Presented here is a detailed description of the distillation set-up and procedure, as well as an overview of potential applications of this method for marine sulfur biogeochemistry/isotope studies. The presented applications include the sulfur isotope analysis of extremely low amounts of sulfate from saline water, the conversion of radiolabeled sulfate into sulfide, the extraction of refractory sulfur from marine sediments, and the use of this method to assess sulfur cycling in Aarhus Bay sediments. Results The STrongly Reducing hydrIodic/hypoPhosphorous/hydrochloric acid (STRIP) reagent is capable of rapidly reducing a wide range of sulfur compounds, including the most oxidized form, sulfate, to hydrogen sulfide. Conversion of as little as approximately 5 micromole sulfate is possible, with a sulfur isotope composition reproducibility of 0.3 permil. Conclusions Although developed many decades ago, this distillation method remains relevant for many modern applications. The STRIP distillation quickly and quantitatively converts sulfur compounds to hydrogen sulfide which can be readily collected in a silver nitrate trap for further use. An application of this method to a study of sulfur cycling in Aarhus Bay demonstrates that we account for all of the sulfur compounds in pore-water, effectively closing the mass balance of sulfur cycling. PMID:24808759

  16. 40 CFR Appendix T to Part 50 - Interpretation of the Primary National Ambient Air Quality Standards for Oxides of Sulfur (Sulfur...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...Ambient Air Quality Standards for Oxides of Sulfur (Sulfur Dioxide...Ambient Air Quality Standards for Oxides of Sulfur (Sulfur Dioxide...ambient air quality standards for Oxides of Sulfur as measured by Sulfur...data from the monitor with the highest average of the four...

  17. 40 CFR Appendix T to Part 50 - Interpretation of the Primary National Ambient Air Quality Standards for Oxides of Sulfur (Sulfur...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...Ambient Air Quality Standards for Oxides of Sulfur (Sulfur Dioxide...Ambient Air Quality Standards for Oxides of Sulfur (Sulfur Dioxide...ambient air quality standards for Oxides of Sulfur as measured by Sulfur...data from the monitor with the highest average of the four...

  18. 40 CFR Appendix T to Part 50 - Interpretation of the Primary National Ambient Air Quality Standards for Oxides of Sulfur (Sulfur...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...Ambient Air Quality Standards for Oxides of Sulfur (Sulfur Dioxide...Ambient Air Quality Standards for Oxides of Sulfur (Sulfur Dioxide...ambient air quality standards for Oxides of Sulfur as measured by Sulfur...data from the monitor with the highest average of the four...

  19. 40 CFR Appendix T to Part 50 - Interpretation of the Primary National Ambient Air Quality Standards for Oxides of Sulfur (Sulfur...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...Ambient Air Quality Standards for Oxides of Sulfur (Sulfur Dioxide...Ambient Air Quality Standards for Oxides of Sulfur (Sulfur Dioxide...ambient air quality standards for Oxides of Sulfur as measured by Sulfur...data from the monitor with the highest average of the four...

  20. Failure to Insert the Iron-Sulfur Cluster into the Rieske Iron-Sulfur Protein Impairs Both Center N and Center P of the

    E-print Network

    Trumpower, Bernard L.

    Failure to Insert the Iron-Sulfur Cluster into the Rieske Iron-Sulfur Protein Impairs Both Center N to the iron-sulfur cluster of the Rieske iron-sulfur protein to a cysteine results in a respiratory-deficient yeast strain due to formation of iron-sulfur protein lacking the iron- sulfur cluster. The Rieske

  1. Extraction, separation, and analysis of high sulfur coal. Final report

    SciTech Connect

    Olesik, S.V.; Pekay, L.A.; Larkins, W. Jr. [comps.

    1992-05-31

    The work described in this report studies the removal of sulfur by oxidative interaction of various cupric salts with coal and also considers the possibility of removing organic sulfur by the selective interaction of supercritical ethanol with the organic coal matrix. Either one of these methods could potentially be used to pretreat coals before burning. The primary purpose of these studies is to ascertain the nature of the chemical reactions occurring, the chemical composition of the resultant products, and information on possible reaction mechanisms. This information should allow prediction of reasonable reaction conditions for the removal of organosulfur compound from coal.

  2. Extraction, separation, and analysis of high sulfur coal

    SciTech Connect

    Olesik, S.V.; Pekay, L.A.; Larkins, W. Jr. (comps.)

    1992-05-31

    The work described in this report studies the removal of sulfur by oxidative interaction of various cupric salts with coal and also considers the possibility of removing organic sulfur by the selective interaction of supercritical ethanol with the organic coal matrix. Either one of these methods could potentially be used to pretreat coals before burning. The primary purpose of these studies is to ascertain the nature of the chemical reactions occurring, the chemical composition of the resultant products, and information on possible reaction mechanisms. This information should allow prediction of reasonable reaction conditions for the removal of organosulfur compound from coal.

  3. Sugar yields from dilute sulfuric acid and sulfur dioxide pretreatments and subsequent enzymatic hydrolysis of switchgrass

    E-print Network

    California at Riverside, University of

    Sugar yields from dilute sulfuric acid and sulfur dioxide pretreatments and subsequent enzymatic%, and 10% wt.% of dry biomass were also tested at 180 °C for 10 min. Sugar yields were tracked for pretreatment and subsequent enzymatic hydrolysis to identify conditions for the highest total sugar yields

  4. Fibrous hybrid of graphene and sulfur nanocrystals for high-performance lithium-sulfur batteries.

    PubMed

    Zhou, Guangmin; Yin, Li-Chang; Wang, Da-Wei; Li, Lu; Pei, Songfeng; Gentle, Ian Ross; Li, Feng; Cheng, Hui-Ming

    2013-06-25

    Graphene-sulfur (G-S) hybrid materials with sulfur nanocrystals anchored on interconnected fibrous graphene are obtained by a facile one-pot strategy using a sulfur/carbon disulfide/alcohol mixed solution. The reduction of graphene oxide and the formation/binding of sulfur nanocrystals were integrated. The G-S hybrids exhibit a highly porous network structure constructed by fibrous graphene, many electrically conducting pathways, and easily tunable sulfur content, which can be cut and pressed into pellets to be directly used as lithium-sulfur battery cathodes without using a metal current-collector, binder, and conductive additive. The porous network and sulfur nanocrystals enable rapid ion transport and short Li(+) diffusion distance, the interconnected fibrous graphene provides highly conductive electron transport pathways, and the oxygen-containing (mainly hydroxyl/epoxide) groups show strong binding with polysulfides, preventing their dissolution into the electrolyte based on first-principles calculations. As a result, the G-S hybrids show a high capacity, an excellent high-rate performance, and a long life over 100 cycles. These results demonstrate the great potential of this unique hybrid structure as cathodes for high-performance lithium-sulfur batteries. PMID:23672616

  5. Airborne sulfur trace species intercomparison campaign: Sulfur dioxide, dimethylsulfide, hydrogen sulfide, carbon disulfide, and carbonyl sulfide

    NASA Technical Reports Server (NTRS)

    Gregory, Gerald L.; Hoell, James M., Jr.; Davis, Douglas D.

    1991-01-01

    Results from an airborne intercomparison of techniques to measure tropospheric levels of sulfur trace gases are presented. The intercomparison was part of the NASA Global Tropospheric Experiment (GTE) and was conducted during the summer of 1989. The intercomparisons were conducted on the Wallops Electra aircraft during flights from Wallops Island, Virginia, and Natal, Brazil. Sulfur measurements intercompared included sulfur dioxide (SO2), dimethylsulfide (DMS), hydrogen sulfide (H2S), carbon disulfide (CS2), and carbonyl sulfide (OCS). Measurement techniques ranged from filter collection systems with post-flight analyses to mass spectrometer and gas chromatograph systems employing various methods for measuring and identifying the sulfur gases during flight. Sampling schedules for the techniques ranged from integrated collections over periods as long as 50 minutes to one- to three-minute samples every ten or fifteen minutes. Several of the techniques provided measurements of more than one sulfur gas. Instruments employing different detection principles were involved in each of the sulfur intercomparisons. Also included in the intercomparison measurement scenario were a host of supporting measurements (i.e., ozone, nitrogen oxides, carbon monoxide, total sulfur, aerosols, etc.) for purposes of: (1) interpreting results (i.e., correlation of any noted instrument disagreement with the chemical composition of the measurement environment); and (2) providing supporting chemical data to meet CITE-3 science objectives of studying ozone/sulfur photochemistry, diurnal cycles, etc. The results of the intercomparison study are briefly discussed.

  6. Protocols for the selective cleavage of carbon-sulfur bonds in coal. Technical report, December 1, 1992February 28, 1993

    Microsoft Academic Search

    M. Bausch; K. K. Ho

    1993-01-01

    Chemical reactions that result in carbon-sulfur bond cleavage are an essential aspect of any protocol designed to remove organic sulfur from coal. Planned in the second year of our project Protocols for the Selective Cleavage of Carbon-Sulfur Bonds in Coal are investigations of reactions in which organic sulfur-containing coal model compounds are subjected to different conditions of temperature, solvent mixtures

  7. SH radical: the key intermediate in sulfur transformation during thermal processing of coal

    SciTech Connect

    Jinding Yan; Jianli Yang; Zhenyu Liu [Chinese Academy of Sciences, Taiyuan (China). State Key Laboratory of Coal Conversion, Institute of Coal Chemistry

    2005-07-01

    To uncouple the complex behavior of sulfur transformation during thermal processing of coal and to elucidate the main mechanism, typical organic and inorganic sulfur compounds impregnated on or mixed with a low-ash char are studied through temperature-programmed decomposition coupled with online mass spectrum analysis (TPD-MS) and followed by temperature-programmed oxidation coupled also with online mass spectrum analysis (TPO-MS) in a temperature range of up to 800{sup o}C. It is evident that the cleavages of C{sub al}-S and C{sub ar}-S bonds, where the subscripts al and ar stand for aliphatic and aromatic carbon, respectively, in the organic compounds result in the formation of SH radicals, which then undergo secondary reactions with the char to form various sulfur compounds such as H{sub 2}S, SO{sub 2}, COS, and elemental sulfur, as well as sulfur structures in the char. H{sub 2} has the ability to stabilize the SH radicals and weaken the interactions between the SH radicals and the char. For the sulfur compounds, which do not generate the SH radical, the only sulfur products detected are those formed directly from the decomposition of the starting sulfur compounds, H{sub 2}S from FeS{sub 2} in H{sub 2} or SO{sub 2} from Fe{sub 2}(SO{sub 4}){sub 3} in He, for example, and no sulfur structure is formed in the char. Minerals have significant effects on the bond cleavage temperature and the reactions of the SH radicals with the char. It is clear that the SH radical is a key species interacting with the char to form secondary sulfur compounds, while H{sub 2}S and SO{sub 2} play no role in the sulfur transformation to the carbon structure. 34 refs., 12 figs., 1 tab.

  8. Sulfur oxidation activities of pure and mixed thermophiles and sulfur speciation in bioleaching of chalcopyrite.

    PubMed

    Zhu, Wei; Xia, Jin-Lan; Yang, Yi; Nie, Zhen-yuan; Zheng, Lei; Ma, Chen-yan; Zhang, Rui-yong; Peng, An-an; Tang, Lu; Qiu, Guan-zhou

    2011-02-01

    The sulfur oxidation activities of four pure thermophilic archaea Acidianus brierleyi (JCM 8954), Metallosphaera sedula (YN 23), Acidianus manzaensis (YN 25) and Sulfolobus metallicus (YN 24) and their mixture in bioleaching chalcopyrite were compared. Meanwhile, the relevant surface sulfur speciation of chalcopyrite leached with the mixed thermophilic archaea was investigated. The results showed that the mixed culture, with contributing significantly to the raising of leaching rate and accelerating the formation of leaching products, may have a higher sulfur oxidation activity than the pure cultures, and jarosite was the main passivation component hindering the dissolution of chalcopyrite, while elemental sulfur seemed to have no influence on the dissolution of chalcopyrite. In addition, the present results supported the former speculation, i.e., covellite might be converted from chalcocite during the leaching experiments, and the elemental sulfur may partially be the derivation of covellite and chalcocite. PMID:21194927

  9. Examination of sulfur forms in coal by direct pyrolysis and flameless ozone-sulfur chemiluminescence detection

    SciTech Connect

    Glinski, R.J.; Xu, Xiaoyang; McGowan, C.W. [Tennessee Technological Univ., Cookeville, TN (United States)

    1995-12-31

    The extremely high selectivity of the newly developed ozone-sulfur chemiluminescence detector (SCD) has been coupled with controlled-temperature pyrolysis to allow qualitative and semiquantitative determination of sulfur forms in coal. Pyrolysis products from the heating of a sulfur containing solid sample were swept directly through a high-temperature conversion tube and into the SCD to yield a strong signal. Upon heating the pyrolysis tube from room temperature to 700 degrees C, several distinct peaks were observed by the SCD, identified as being due to aliphatic sulfides and thiols, elemental sulfur, simple thiophenes, pyrite, and complex thiophenes. Standard addition of the pure inorganic substances provided semiquantitative determinations. Three coals were examined and could be quickly and easily distinguished by their sulfur forms. The results are compared with those of other pyrolysis methods.

  10. Comparison of the UCB sulfur recovery process with conventional sulfur recovery technology for treating recycle gas from a crude oil residuum hydrotreater. [UCBSRP sulfur recovery process

    Microsoft Academic Search

    S. Lynn; D. W. Neumann; S. F. Sciamanna; F. H. Vorhis

    1986-01-01

    The University of California, Berkeley, Sulfur Recovery Process (UCBSRP) is being developed as an alternative to conventional sulfur recovery technology for removing hydrogen sulfide from gas streams and converting it to elemental sulfur. In the UCBSRP the hydrogen sulfide is absorbed by a physical solvent and the resulting solution of HâS is mixed with a stoichiometrically equivalent amount of slulfur

  11. A primer on sulfur for the planetary geologist

    NASA Technical Reports Server (NTRS)

    Theilig, E.

    1982-01-01

    Sulfur has been proposed as the dominant composition for the volcanic material on Io. Sulfur is a complex element which forms many intramolecular and intermolecular allotropes exhibiting a variety of physical properties. Cyclo-S8 sulfur is the most abundant and stable molecular form. The important molecular species within liquid sulfur change in concentration with temperature. Concentrations of the allotropes control the physical properties of the melt. Discontinuities in density, viscosity, and thermal properties reflect the polymerization process within liquid sulfur. Variations in the melting point are related to autodissociation of the liquid. Many solids forms of sulfur have been identified but only orthorhombic alpha and monoclinic beta sulfur, both composed of cyclo-S8 sulfur, are stable under terrestrial conditions. Physical properties of solid sulfur are dependent on the allotrope and, in some cases, the thermal history. Three natural terrestrial sulfur flows are described: (1) Siretoko-Iosan, Japan; (2) Volcan Azufre, Galapagos Islands; and (3) Mauna Loa, Hawaii. All of the flows are associated with fumarolic areas and are considered to have formed by the melting and mobilization of sulfur deposits. Surface textures of the flows indicate a behavior of molten sulfur similar to that of silicate lava. Channels, rivulets, and lobate edges were described for the flows. The solidification of man-made sulfur flows formed as part of the Frasch mining process by which sulfur is removed from the subsurface in a liquid state is described.

  12. 40 CFR 721.7770 - Alkylphenoxypoly(oxyethylene) sulfuric acid ester, substituted amine salt.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...Alkylphenoxypoly(oxyethylene) sulfuric acid ester, substituted amine salt...Alkylphenoxypoly(oxyethylene) sulfuric acid ester, substituted amine salt...alkyl phenoxypoly(oxyethylene) sulfuric acid ester, substituted amine...

  13. 40 CFR 721.7770 - Alkylphenoxypoly(oxyethylene) sulfuric acid ester, substituted amine salt.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...Alkylphenoxypoly(oxyethylene) sulfuric acid ester, substituted amine salt...Alkylphenoxypoly(oxyethylene) sulfuric acid ester, substituted amine salt...alkyl phenoxypoly(oxyethylene) sulfuric acid ester, substituted amine...

  14. 40 CFR 721.7770 - Alkylphenoxypoly(oxyethylene) sulfuric acid ester, substituted amine salt.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...Alkylphenoxypoly(oxyethylene) sulfuric acid ester, substituted amine salt...Alkylphenoxypoly(oxyethylene) sulfuric acid ester, substituted amine salt...alkyl phenoxypoly(oxyethylene) sulfuric acid ester, substituted amine...

  15. Clues to early diagenetic sulfurization processes from mild chemical cleavage of labile sulfur-rich geomacromolecules

    NASA Astrophysics Data System (ADS)

    Adam, P.; Schneckenburger, P.; Schaeffer, P.; Albrecht, P.

    2000-10-01

    Macromolecular fractions, isolated from the solvent extract of sulfur-rich Recent (Siders Pond, USA; Lake Cadagno, Switzerland; Walvis Bay, Namibia) and immature sediments (Gibellina, Messinian of Sicily; Vena del Gesso, Messinian of Italy), were investigated by chemical degradation using sodium ethanethiolate/methyliodide. This mild reagent which cleaves polysulfide bonds to yield methylsulfides has the advantage over other methods of leaving intact other functionalities (like double bonds) and preserving sulfur atoms at their incorporation site. The method is, therefore, well-suited to the molecular level investigation of sulfur-rich macromolecules from Recent sediments containing highly functionalized polysulfide-bound subunits. In Recent anoxic sulfur-rich sediments, the release of various methylthioethers clearly demonstrates that intermolecular sulfurization of organic matter does occur at the earliest stages of diagenesis. Steroids and phytane derivatives are the major sulfurized lipids, a feature also observed in more mature sulfur-rich sediments. Several phytene derivatives, such as cis and trans 1-methylthiophyt-2-enes, as well as methylthiosteroids, including 5?- and 5?-3-(methylthio)-cholest-2-enes, were identified by comparison with synthesized standards. Steroid methylthioenolethers are released from polysulfide-bound steroid enethiols present in the macromolecular fractions. The latter, which correspond to thioketones, can be considered as intermediates in the reductive sulfurization pathway leading from steroid ketones to polysulfide-bound saturated steroid skeletons and are characterized for the first time in the present study. Thus, it could be shown that the major part of the polysulfide-bound lipids occurring in Recent sediments is apparently the result of sulfurization processes affecting carbonyls (aldehydes and ketones). The unsaturated methylthioethers obtained from Recent sediments were not present in more mature evaporitic samples, which suggests that polysulfide-bound unsaturated thiols are intermediates formed during the first sulfurization steps occurring soon after deposition and that they are rapidly transformed by various processes taking place during early diagenesis, notably to yield their saturated counterparts.

  16. An Aerosol Condensation Model for Sulfur Trioxide

    SciTech Connect

    Grant, K E

    2008-02-07

    This document describes a model for condensation of sulfuric acid aerosol given an initial concentration and/or source of gaseous sulfur trioxide (e.g. fuming from oleum). The model includes the thermochemical effects on aerosol condensation and air parcel buoyancy. Condensation is assumed to occur heterogeneously onto a preexisting background aerosol distribution. The model development is both a revisiting of research initially presented at the Fall 2001 American Geophysical Union Meeting [1] and a further extension to provide new capabilities for current atmospheric dispersion modeling efforts [2]. Sulfuric acid is one of the most widely used of all industrial chemicals. In 1992, world consumption of sulfuric acid was 145 million metric tons, with 42.4 Mt (mega-tons) consumed in the United States [10]. In 2001, of 37.5 Mt consumed in the U.S., 74% went into producing phosphate fertilizers [11]. Another significant use is in mining industries. Lawuyi and Fingas [7] estimate that, in 1996, 68% of use was for fertilizers and 5.8% was for mining. They note that H{sub 2}SO{sub 4} use has been and should continue to be very stable. In the United States, the elimination of MTBE (methyl tertiary-butyl ether) and the use of ethanol for gasoline production are further increasing the demand for petroleum alkylate. Alkylate producers have a choice of either a hydrofluoric acid or sulfuric acid process. Both processes are widely used today. Concerns, however, over the safety or potential regulation of hydrofluoric acid are likely to result in most of the growth being for the sulfuric acid process, further increasing demand [11]. The implication of sulfuric acid being a pervasive industrial chemical is that transport is also pervasive. Often, this is in the form of oleum tankers, having around 30% free sulfur trioxide. Although sulfuric acid itself is not a volatile substance, fuming sulfuric acid (referred to as oleum) is [7], the volatile product being sulfur trioxide. Sulfate aerosols and mist may form in the atmosphere on tank rupture. From chemical spill data from 1990-1996, Lawuyi02 and Fingas [7] prioritize sulfuric acid as sixth most serious. During this period, they note 155 spills totaling 13 Mt, out of a supply volume of 3700 Mt. Lawuyi and Fingas [7] summarize information on three major sulfuric acid spills. On 12 February 1984, 93 tons of sulfuric acid were spilled when 14 railroad cars derailed near MacTier, Parry Sound, Ontario. On 13 December 1978, 51 railroad cars derailed near Springhill, Nova Scotia. One car, containing 93% sulfuric acid, ruptured, spilling nearly its entire contents. In July 1993, 20 to 50 tons of fuming sulfuric acid spilled at the General Chemical Corp. plant in Richmond, California, a major industrial center near San Francisco. The release occurred when oleum was being loaded into a nonfuming acid railroad tank car that contained only a rupture disk as a safety device. The tank car was overheated and this rupture disk blew. The resulting cloud of sulfuric acid drifted northeast with prevailing winds over a number of populated areas. More than 3,000 people subsequently sought medical attention for burning eyes, coughing, headaches, and nausea. Almost all were treated and released on the day of the spill. By the day after the release, another 5,000 people had sought medical attention. The spill forced the closure of five freeways in the region as well as some Bay Area Rapid Transit System stations. Apart from corrosive toxicity, there is the additional hazard that the reactions of sulfur trioxide and sulfuric acid vapors with water are extremely exothermic [10, 11]. While the vapors are intrinsically denser than air, there is thus the likelihood of strong, warming-induced buoyancy from reactions with ambient water vapor, water-containing aerosol droplets, and wet environmental surface. Nordin [12] relates just such an occurrence following the Richmond, CA spill, with the plume observed to rise to 300 m. For all practical purposes, sulfur trioxide was the constituent released from the heated tank

  17. Sulfur copolymers for infrared optical imaging

    NASA Astrophysics Data System (ADS)

    Namnabat, S.; Gabriel, J. J.; Pyun, J.; Norwood, R. A.; Dereniak, E. L.; van der Laan, J.

    2014-06-01

    The development of organic polymers with low infrared absorption has been investigated as a possible alternative to inorganic metal oxide, semiconductor, or chalcogenide-based materials for a variety of optical devices and components, such as lenses, goggles, thermal imaging cameras and optical fibers. In principle, organic-based polymers are attractive for these applications because of their low weight, ease of processing, mechanical toughness, and facile chemical variation using commercially available precursors. Herein we report on the optical characterization of a new class of sulfur copolymers that are readily moldable, transparent above 500 nm, possess high refractive index (n > 1.8) and take advantage of the low infrared absorption of S-S bonds for potential use in the mid-infrared at 3-5 microns. These materials are largely made from elemental sulfur by an inverse vulcanization process; in the current study we focus on the properties of a chemically stable, branched copolymer of poly(sulfur-random-1,3-diisopropenylbenzene) (poly(S-r- DIB). Copolymers with elemental sulfur content ranging from 50% to 80% by weight were studied by UV-VIS spectroscopy, FTIR, and prism coupling for refractive index measurement. Clear correlation between material composition and the optical properties was established, confirming that the high polarizability of the sulfur atom leads to high refractive index while also maintaining low optical loss in the infrared.

  18. Development of enhanced sulfur rejection processes

    SciTech Connect

    Yoon, R.H.; Luttrell, G.; Adel, G.; Richardson, P.E.

    1993-03-23

    Research at Virginia Tech led to two complementary concepts for improving the removal of inorganic sulfur from much of the Eastern US coals. One controls the surface properties of coal pyrite (FeS[sub 2]) by electrochemical-.potential control, referred to as the Electrochemically Enhanced Sulfur Rejection (EESR) Process: The second controls the flotation of middlings, i.e., particles composed of pyrite with coal inclusions by using polymeric reagents to react with pyrite and convert the middlings to hydrophilic particles, and is termed the Polymer Enhanced Sulfur Rejection (PESR) Process. These new concepts are based on recent research establishing the two main reasons why flotation fails to remove more than about 50% of the pyritic sulfur from coal: superficial oxidization of liberated pyrite to form polysulfide oxidation products so that a part of the liberated pyrite floats with the coal; and hydrophobic coal inclusions in the middlings dominating their flotation so that the middlings also float with the coal. These new pyritic-sulfur rejection processes do not require significant modifications of existing coal preparation facilities, enhancing their adoptability by the coal industry. It is believed that they can be used simultaneously to achieve both free pyrite and locked pyrite rejection.

  19. Sulfur 'Concrete' for Lunar Applications - Environmental Considerations

    NASA Technical Reports Server (NTRS)

    Grugel, R. N.

    2008-01-01

    Commercial use of sulfur concrete on Earth is well established, particularly in corrosive, e.g., acid and salt, environments. Having found troilite (FeS) on the Moon raises the question of using extracted sulfur as a lunar construction material, an attractive alternative to conventional concrete as it does not require water. For the purpose of this Technical Memorandum, it is assumed that lunar ore is mined, refined, and the raw sulfur processed with appropriate lunar regolith to form, for example, bricks. With this stipulation, it is then noted that the viability of sulfur concrete in a lunar environment, which is characterized by lack of an atmosphere and extreme temperatures, is not well understood. The work presented here evaluates two sets of small sulfur concrete samples that have been prepared using JSC-1 lunar simulant as an aggregate addition. One set was subjected to extended periods in high vacuum to evaluate sublimation issues, and the other was cycled between room and liquid nitrogen temperatures to investigate their subsequent mechanical integrity. Results are presented from both investigations, discussed, and put into the context of the lunar environment.

  20. New developments in lithium sulfur batteries

    NASA Astrophysics Data System (ADS)

    Xu, Rui; Belharouak, Ilias; Zhang, Xiaofeng; Polzin, Bryant; Li, James C. M.

    2013-05-01

    In this work, efforts were conducted in order to mitigate the issue of polysulfides dissolution and hence to improve the capacity and efficiency of Li-sulfur cells. The first approach was achieved by optimizing the amount of sulfur that can be contained in the sulfur/carbon electrode. Five sulfur/carbon ratios were prepared- (1) 50/50, (2) 60/40, (3) 70/30, (4) 80/20, and (5) 90/10- to study the effect of carbon contents on electrochemical cycling. The second approach was by adding nano-sized TiO2 particles having a large specific surface area as the polysulfide adsorbing agent in the electrodes. The impact of nano-sized TiO2 particles in improving the electrochemical properties of sulfur electrodes was investigated using CV measurements and charge/discharge tests. To further enhance the efficiency and cycling stability of Li-S batteries, a novel polysulfide electrolyte was developed. This new electrolyte mainly consisted of pre-dissolved lithium polysulfides (Li2Sx) as an alternative electrolyte salt to replace the lithium bis(trifluoromethanesulfone)imide (LiTFSI). We also used LiNO3 to mitigate the shuttle mechanism that occurs in Li-S cells during the charge and discharge. By creating a dynamic equilibrium at the interface of the cathode and electrolyte, the dissolution of lithium polysulfides, and thus the loss of active materials from the cathode during the discharge and charge of the cell, was greatly prevented.