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1

Process for removing sulfur compounds  

SciTech Connect

A process for removing sulfur compounds including at least hydrogen sulfide and sulfur dioxide from a sulfur contaminated fluid stream having a concentration of said sulfur compounds is described comprising the step of: contacting said sulfur contaminated fluid stream with an absorption composition comprising: zinc oxide in an amount between about 60 and about 90 weight percent; zinc phosphate in an amount between about 10 and about 40 weight percent; and alumina in an amount up to about 30 weight percent to produce a treated effluent stream having a substantially reduced concentration of said sulfur compounds.

Lowery, R.E.; Engelbert, D.R.

1993-06-15

2

Microbial Metabolism of Inorganic Sulfur Compounds  

Microsoft Academic Search

Inorganic sulfur compounds are used by microorganisms (bacteria, fungi, algae) and plants for assimilation, i.e. biosynthesis of sulfur-containing cell constituents.Quantitatively, within the biogeochemical cycle of sulfur the utilization of inorganic sulfur compounds in bacterial energy metabolism, i.e. dissimilatory sulfur utilization, is of far higher importance. Reduced sulfur compounds serve as electron donors for photosynthesis and respiration, whereas inorganic sulfur compounds

Hans G. Trper

1985-01-01

3

Ambient Air Monitoring for Sulfur Compounds  

ERIC Educational Resources Information Center

|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)|

Forrest, Joseph; Newman, Leonard

1973-01-01

4

Formation and Decomposition of Sulfur Compounds in Dispenser Cathodes.  

National Technical Information Service (NTIS)

Formation of sulfur compounds during cathode processing and generation of sulfur during cathode operation were examined using thermodynamic data. Sulfur compounds can be formed in dispenser cathodes exposed to a source of hydrogen sulfide (such as stainle...

R. A. Lipeles

1987-01-01

5

Diagenetic sulfurization of reactive compounds in late Paleozoic sediments  

Microsoft Academic Search

New sulfur isotope data for pairs of organic (OBS: organically bound sulfur from kerogen) and inorganic sulfur (CRS: chromium reducible sulfur, mostly pyrite) compounds of late Palaeozoic sediments (n=145) facilitate an improved insight into diagenetic reactions between bacterially formed hydrogen sulfide and reactive phases in the sediment (i.e. iron and organic matter). Most informative is a very strong correlation between

E. A. Westphal; H. Strauss

2003-01-01

6

Characterization of Sulfur Compounds in Coffee Beans by Sulfur K-XANES Spectroscopy  

SciTech Connect

In this 'feasibility study' the influence of roasting on the sulfur speciation in Mexican coffee beans was investigated by sulfur K-XANES Spectroscopy. Spectra of green and slightly roasted beans could be fitted to a linear combination of 'standard' reference spectra for biological samples, whereas longer roasting obviously involves formation of additional sulfur compounds in considerable amounts.

Lichtenberg, H.; Hormes, J. [Center for Advanced Microstructures and Devices, Louisiana State University, 6980 Jefferson Hwy., Baton Rouge, LA 70806 (United States); Institute of Physics, University of Bonn, Nussallee 12, 53115 Bonn (Germany); Prange, A. [Center for Advanced Microstructures and Devices, Louisiana State University, 6980 Jefferson Hwy., Baton Rouge, LA 70806 (United States); Niederrhein University of Applied Sciences, Rheydter Strasse 277, 41065 Moenchengladbach (Germany); Modrow, H. [Institute of Physics, University of Bonn, Nussallee 12, 53115 Bonn (Germany)

2007-02-02

7

Finishing of Diesel Fuel to Remove Sulfur Compounds after Hydrotreating  

Microsoft Academic Search

A method for finishing hydrotreated diesel fuel to remove sulfur compounds in two stages is described. In the first stage, sulfur compounds remaining in the fuel are oxidized into sulfones with hydrogen peroxide in the presence of molybdenum compounds and in the second stage, the sulfones are decomposed into sulfur dioxide and hydrocarbon on aluminosilicate catalyst. The fuel obtained satisfies

A. Kh. Sharipov; V. R. Nigmatullin

2005-01-01

8

Two stage sorption of sulfur compounds  

DOEpatents

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.

Moore, W.E.

1991-12-31

9

[Determination and distribution of sulfur compounds in coked gasoline by gas chromatography-sulfur chemiluminescence detection].  

PubMed

The method for the separation and determination of sulfur compounds in coked gasoline by gas chromatography-sulfur chemiluminescence detection (GC-SCD) was established. Seventy-four sulfur compounds including hydrogen sulfide, mercaptans, sulfides, disulfides, thiophene, alkyl thiophenes, benzothiophene, alkyl benzothiophenes in a coked gasoline sample were identified by standard samples and past identified results. The retention indexes of different sulfur compounds in coked gasoline under programmed temperature condition were calculated based on the retention times of hydrosulfide, ethyl mercaptan, n-propyl mercaptan, thiophene, 2-methyl thiophene, 2-ethylthiophene, 2-propylthiophene, C4-thiophene (t(R) = 40.28 min), benzothiophene, and methylbenzothiophene (t(R) = 58.13 min). The relative standard deviations of the determination results of main sulfur compounds (isopropyl mercaptan, n-propyl mercaptan, n-butyl mercaptan, 2-methylthiophene, 3-methylthiophene, 2, 4-dimethylthiophene, 2,3,4-trimethylthiophene) in coked gasoline were less than 5%, and the detection limit for sulfur was 0.05 mg/L. The linear range of sulfur was 0.2 - 400 mg/L for each sulfur compounds (r2 = 0. 999). The contents of sulfur compounds, especially the content of mercaptan, are much more than those in the catalytic gasoline. There is also a big difference in the sulfur contents between 2-methylthiophene and 3-methylthiophene. The data can be useful for the study of hydrodesulfurizing catalyst and industrial process planning. PMID:17679435

Yang, Yongtan; Wang, Zheng

2007-05-01

10

Sulfur and nitrogen compounds in urban aerosols  

SciTech Connect

Some results are reported for sulfate, nitrate, and related ionic species taken from a detailed chemical and meteorological data base that has been accumulated for the New York subregion since 1976 (the data base is generally referred to as the New York Summer and Winter Aerosol Studies). Some of the experimental advances in sampling and analysis of aerosol sulfur and nitrogen compounds and related gases are described that offer promise for the measurement of all components of the atmospheric sulfate-nitrate-SO/sub 2/-NO(x)-NH/sub 3/ system with a time resolution of a few minutes. These advances include aerosol sulfur measurement by real-time FPD, gaseous nitric acid sampling and analysis, and continuous ammonia analysis.

Tanner, R.L.

1980-01-01

11

Oxidation of Inorganic Sulfur Compounds by Obligately Organotrophic Bacteria  

Microsoft Academic Search

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

D. Yu. Sorokin

2003-01-01

12

Reduced Sulfur Compound Oxidation byThiobacillus caldus  

Microsoft Academic Search

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 cyanidem-chlorophenyl-hydrazone had

KEVIN B. HALLBERG; MARK DOPSON

1996-01-01

13

Treatment of Waste Gases Contaminated with Odorous Sulfur Compounds  

Microsoft Academic Search

Due to their very low odor threshold value (ppbv range), high toxicity, and potential corrosive effect, the presence of volatile sulfur compounds in waste gases deserves special attention. These sulfur compounds mainly include hydrogen sulfide, dimethyl sulfide, dimethyl disulfide, meth-anethiol, carbon disulfide, and carbonyl sulfide. Contrary to natural emissions, anthropogenic emissions may contribute to local concentrations, strongly exceeding the odor

E. Smet; P. Lens; H. Van Langenhove

1998-01-01

14

Analyze trace sulfur compounds in hydrocarbon gas streams  

SciTech Connect

Measuring trace sulfur compounds in fuel gases has been an industry requirement for many years and now plays a role in a variety of processing areas. One such area involves controlling hydrogen sulfide (H{sub 2}S) and other sulfur compounds in natural gas and fuel gas to prevent corrosion of pipelines and other equipment. Further, using sulfur compounds as odorants makes natural gas safer. In addition, the presence of sulfur compounds in fuel gases used to fire boilers and incinerators contributes to overall facility SO{sub 2} emissions. In all cases, the ability to accurately identify and quantify sulfur compounds is playing an increasingly important role. Despite improvements in analytical technology, little attention has been given to proper sampling of gas streams for trace sulfur. Most existing sample stations and equipment in refineries are inadequate for these purposes. While the hydrocarbon background gases are relatively stable, sulfur compounds found in these process streams are very reactive. Improper collection and storage of the gas sample results in a nonrepresentative sample and a poor result, regardless of the quality of the analytical method. Specific sampling and analytical techniques are successfully used to measure sulfur content of hydrocarbon gas streams as shown here.

Anderson, M.; Dimmer, R.C. [Brimstone Engineering Services, Inc., Englewood, CO (United States)

1997-04-01

15

Electrophilic heterocyclization of unsaturated sulfur and phosphorus compounds  

SciTech Connect

The literature on the electrophilic heterocyclization of unsaturated sulfur and phosphorus compounds has been reviewed. The factors influencing the reactivity of unsaturated compounds in such reactions are discussed, and data on the stereochemistry of the addition are presented.

Gevaza, Yu.I.; Staninets, V.I.

1986-09-01

16

Organic sulfur compounds in crude oils of West Kazakhstan  

Microsoft Academic Search

This article reports on a study of the distribution of organic sulfur compounds (mercaptans, disulfides, and sulfides) in crude oils and in 50°C cuts, and also in gas condensates. Notes that the crude oils of West Kazakhstan, particularly the field that have been discovered recently, are extremely diverse in physiochemical properties, particularly in their content and structure of organic sulfur

V. V. Ryzhenko; N. S. Buyanova; A. V. Kotova; N. K. Nadirov

1983-01-01

17

Manual method for measurement of reduced sulfur compounds  

SciTech Connect

A manual method for measuring reduced sulfur compounds in kraft pulp mill and sulfur recovery plant emissions was evaluated. The method involves removing SO/sub 2/ from the gas stream (if present) with a citric acid-potassium citrate buffer that passes reduced sulfur compounds; thermal oxidation of all reduced sulfur compounds to SO/sub 2/; collection of the SO/sub 2/ in H/sub 2/O/sub 2/; and a titrimetric analysis of the H/sub 2/O/sub 2/ for SO/sub 4//sup 2 -/. A heated filter removes alkaline particulate matter that would produce a negative interference if absorbed by the buffer. When used at kraft pulp mills, the method agrees closely with Reference Method 16, provided that nonregulated reduced sulfur compounds, such as carbonyl sulfide, are not present in the emissions. At sulfur recovery plants, nonregulated reduced sulfur compounds, such as thiophene, are likely to be present in the emissions and will produce a positive bias in the results obtained with this method. The precision of the method ranges from 1 to 7% relative standard deviation.

Margeson, J.H.; Knoll, J.E.; Midgett, M.R.; Ferguson, B.B.; Schworer, P.J.

1985-12-01

18

Method for removal of sulfur compounds from a gas  

SciTech Connect

This invention relates to a process for the removal of sulfur compounds from a gas stream which consists of contacting said gas stream with alkali metal salts of sulfonamides or resins containing sulfonamide functionalities.

Frech, K.J.; Tazuma, J.J.

1981-08-11

19

Process for removal of sulfur compounds from conjugated diolefins  

Microsoft Academic Search

This patent describes a process for reducing the level of sulfur compounds selected from hydrogen sulfide and carbon disulfide in a sulfur compound-containing liquid conjugated diolefin hydrocarbon having an atmospheric boiling point in the range from about -5° to about 45°C. The process consists of contacting the liquid diolefin at a temperature up to about the boiling point of the

Slaugh

1986-01-01

20

Effects of Inorganic Sulfur Addition on Fluxes of Volatile Sulfur Compounds in Sphagnum Peatlands.  

National Technical Information Service (NTIS)

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), On...

W. Z. Demello M. E. Hines S. E. Bayley

1992-01-01

21

Uses of Lunar Sulfur.  

National Technical Information Service (NTIS)

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 extracta...

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

1988-01-01

22

Organic sulfur compounds in crude oils of West Kazakhstan  

Microsoft Academic Search

The group composition of these compounds in the crude oils and cuts was determined by methods that have been used previously [1-4]. The data are listed in Table 1. The oils from the Tortai, Kultuk, and Zhilankabak fields are classed as low-sulfur(total sulfur contents 0.22%, 0.44%, and 0.47%, respectively). The yield of light cuts below 200~C varies from 7.7%to 30.4%,

V. V. Ryzhenko; A. V. Kotova; N. S. Buyanova; N. K. Nadirov

1982-01-01

23

A Systematic Presentation of Organic Phosphorus and Sulfur Compounds.  

ERIC Educational Resources Information Center

|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)|

Hendrickson, James B.

1985-01-01

24

Uses of lunar sulfur  

SciTech Connect

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.

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

1988-01-01

25

Antioxidant combinations of molybdenum complexes and organic sulfur compounds for lubricating oils  

SciTech Connect

An antioxidant additive combination for lubricating oils is prepared by combining (a) a sulfur containing molybdenum compound prepared by reacting an ammonium tetrathiomolybdate, and a basic nitrogen compound, with (b) an organic sulfur compound.

deVries, L.; King, J.M.

1983-09-06

26

SPECIATION EFFECTS OF ALLYL SULFUR COMPOUNDS ON ABERRANT CRYPT FORMATION  

Technology Transfer Automated Retrieval System (TEKTRAN)

Garlic and its associated allyl sulfur compounds have been shown to reduce the incidence of chemically induced breast, colon, skin, uterine, esophagus, and lung cancers. Aqueous suspensions and high exposure to S-allyl cysteine have been shown to inhibit early stage colon carcinogenesis, including a...

27

Microbial removal of organic sulfur from coal (bacterial degradation of sulfur-containing heterocyclic compounds)  

Microsoft Academic Search

The presence of substantial levels of sulfur in coal is a major source of air pollution, and considerable efforts are being made to devise a cost-effective way of removing the sulfur. One method is to mutate a laboratory species, Escherichia coli, an organism which is genetically well-understood and whose pathways for the metabolism of sulfur-containing amino acids have been extensively

Klubek

1990-01-01

28

Service properties of jet fuels in relation to group composition of sulfur compounds in fuel  

Microsoft Academic Search

Most middle-distillate fuels are produced from medium- and high-sulfur crude oils. Even with the increasing use of hydrotreating processes, jet fuels still contain sulfur compounds that may vary in group composition. Numerous studies [1, 2] have been devoted to the matter of how sulfur compounds influence the service properties of fuels. The compounds that have been studied in the most

Ya. B. Chertkov; E. P. Seregin; T. I. Kirsanova; A. N. Romanov; T. A. Lifanova; G. B. Skovorodin

1976-01-01

29

X-ray K ? 1 emission spectra of sulfur in dialkyl sulfides and some heterocyclic compounds of sulfur  

Microsoft Academic Search

The x-ray K~ffemission spectra were obtained for the sulfur in dialkyl sulfides RzS (where R = CH~, C2Hs, C4H9, C6H13, CsHIT), diphenyl sulfide, and some heterocyclic compounds. By comparison with calculations the emission peaks were assigned to electronic transitions from levels of corresponding symmetry. In the unsaturated compounds interaction was detected between the unshared electron pair of the sulfur atom

L. N. Mazalov; A. P. Sadovskii; . A. Gal'tsova; V. V. Murakhtanov; V. G. Torgov; V. M. Bertenev; A. P. Zeif

1973-01-01

30

Sulfur emissions  

Microsoft Academic Search

The Environmental Defense Fund challenges a recent conclusion of the Advisory Committee on Oceans and International Environmental and Scientific Affairs ''that nitrogen oxides were the limiting factor in the formation of acids, including sulfuric acid, in acid rain.'' Acceptance of this would mean shifting strategies to reduce acidic sulfur deposition by reducing regional sulfur dioxide SO emissions in eastern North

1985-01-01

31

Occurrence and Abatement of Volatile Sulfur Compounds during Biogas Production  

Microsoft Academic Search

Volatile sulfur compounds (VSCs) in biogas originating from a biogas production plant and from a municipal sewage water treatment plant were identified. Samples were taken at various stages of the biogas-producing process, including upgrading the gas to vehicle-fuel quality. Solid-phase microextraction was used for preconcentra-tion of the VSCs, which were subsequently analyzed using gas chromatography in combination with mass spectrom-etry.

Frs Annika T. Andersson; Anna Karlsson; Bo H. Svensson; Jrgen Ejlertsson

2004-01-01

32

Analysis of organic sulfur compounds in wine aroma.  

PubMed

Sulfur-containing compounds in wines have been extensively studied because of their effect on wine aroma. The aim of this paper was to give an overview on the analytical methods developed to determine them in wines with special emphasis on gas chromatographic methods, as well as the results obtained. In addition, the problems occurring in application of the common extraction procedures, such as liquid-liquid extraction, static and dynamic headspace and solid-phase microextraction, are presented and discussed. PMID:10905736

Mestres, M; Busto, O; Guasch, J

2000-06-01

33

Quadruple sulfur isotope constraints on the origin and cycling of volatile organic sulfur compounds in a stratified sulfidic lake  

NASA Astrophysics Data System (ADS)

We have quantified the major forms of volatile organic sulfur compounds (VOSCs) distributed in the water column of stratified freshwater Fayetteville Green Lake (FGL), to evaluate the biogeochemical pathways involved in their production. The lake's anoxic deep waters contain high concentrations of sulfate (12-16 mmol L-1) and sulfide (0.12 ?mol L-1 to 1.5 mmol L-1) with relatively low VOSC concentrations, ranging from 0.1 nmol L-1 to 2.8 ?mol L-1. Sulfur isotope measurements of combined volatile organic sulfur compounds demonstrate that VOSC species are formed primarily from reduced sulfur (H2S/HS-) and zero-valent sulfur (ZVS), with little input from sulfate. Thedata support a role of a combination of biological and abiotic processes in formation of carbon-sulfur bonds between reactive sulfur species and methyl groups of lignin components. These processes are responsible for very fast turnover of VOSC species, maintaining their low levels in FGL. No dimethylsulfoniopropionate (DMSP) was detected by Electrospray Ionization Mass Spectrometry (ESI-MS) in the lake water column or in planktonic extracts. These observations indicate a pathway distinct from oceanic and coastal marine environments, where dimethylsulfide (DMS) and other VOSC species are principally produced via the breakdown of DMSP by plankton species.

Oduro, Harry; Kamyshny, Alexey; Zerkle, Aubrey L.; Li, Yue; Farquhar, James

2013-11-01

34

Tandem sulfur chemiluminescence and flame ionization detection with planar microfluidic devices for the characterization of sulfur compounds in hydrocarbon matrices.  

PubMed

The detection of sulfur compounds in different hydrocarbon matrices, from light hydrocarbon feedstocks to medium synthetic crude oil feeds provides meaningful information for optimization of refining processes as well as demonstration of compliance with petroleum product specifications. With the incorporation of planar microfluidic devices in a novel chromatographic configuration, sulfur compounds from hydrogen sulfide to alkyl dibenzothiophenes and heavier distributions of sulfur compounds over a wide range of matrices spanning across a boiling point range of more than 650C can be characterized, using one single analytical configuration in less than 25min. In tandem with a sulfur chemiluminescence detector for sulfur analysis is a flame ionization detector. The flame ionization detector can be used to establish the boiling point range of the sulfur compounds in various hydrocarbon fractions for elemental specific simulated distillation analysis as well as profiling the hydrocarbon matrices for process optimization. Repeatability of less than 3% RSD (n=20) over a range of 0.5-1000 parts per million (v/v) was obtained with a limit of detection of 50 parts per billion and a linear range of 0.5-1000 parts per million with a correlation co-efficient of 0.998. PMID:23726084

Luong, J; Gras, R; Shellie, R A; Cortes, H J

2013-05-02

35

The role of labile sulfur compounds in thermochemical sulfate reduction  

USGS Publications Warehouse

The reduction of sulfate to sulfide coupled with the oxidation of hydrocarbons to carbon dioxide, commonly referred to as thermochemical sulfate reduction (TSR), is an important abiotic alteration process that most commonly occurs in hot carbonate petroleum reservoirs. In the present study we focus on the role that organic labile sulfur compounds play in increasing the rate of TSR. A series of gold-tube hydrous pyrolysis experiments were conducted with n-octane and CaSO4 in the presence of reduced sulfur (e.g. H2S, S??, organic S) at temperatures of 330 and 356 ??C under a constant confining pressure. The in-situ pH was buffered to 3.5 (???6.3 at room temperature) with talc and silica. For comparison, three types of oil with different total S and labile S contents were reacted under similar conditions. The results show that the initial presence of organic or inorganic sulfur compounds increases the rate of TSR. However, organic sulfur compounds, such as 1-pentanethiol or diethyldisulfide, were significantly more effective in increasing the rate of TSR than H2S or elemental sulfur (on a mole S basis). The increase in rate is achieved at relatively low concentrations of 1-pentanethiol, less than 1 wt% of the total n-octane, which is comparable to the concentration of organic S that is common in many oils (???0.3 wt%). We examined several potential reaction mechanisms to explain the observed reactivity of organic LSC. First, the release of H2S from the thermal degradation of thiols was discounted as an important mechanism due to the significantly greater reactivity of thiol compared to an equivalent amount of H2S. Second, we considered the generation of olefines in association with the elimination of H2S during thermal degradation of thiols because olefines are much more reactive than n-alkanes during TSR. In our experiments, olefines increased the rate of TSR, but were less effective than 1-pentanethiol and other organic LSC. Third, the thermal decomposition of organic LSC creates free-radicals that in turn might initiate a radical chain-reaction that creates more reactive species. Experiments involving radical initiators, such as diethyldisulfide and benzyldisulfide, did not show an increase in reactivity compared to 1-pentanethiol. Therefore, we conclude that none of these can sufficiently explain our observations of the initial stages of TSR; they may, however, be important in the later stages. In order to gain greater insight into the potential mechanism for the observed reactivity of these organic sulfur compounds during TSR, we applied density functional theory-based molecular modeling techniques to our system. The results of these calculations indicate that 1-pentanethiol or its thermal degradation products may directly react with sulfate and reduce the activation energy required to rupture the first S-O bond through the formation of a sulfate ester. This study demonstrates the importance of labile sulfur compounds in reducing the onset timing and temperature of TSR. It is therefore essential that labile sulfur concentrations are taken into consideration when trying to make accurate predictions of TSR kinetics and the potential for H2S accumulation in petroleum reservoirs. ?? 2008.

Amrani, A.; Zhang, T.; Ma, Q.; Ellis, G. S.; Tang, Y.

2008-01-01

36

The role of labile sulfur compounds in thermochemical sulfate reduction  

NASA Astrophysics Data System (ADS)

The reduction of sulfate to sulfide coupled with the oxidation of hydrocarbons to carbon dioxide, commonly referred to as thermochemical sulfate reduction (TSR), is an important abiotic alteration process that most commonly occurs in hot carbonate petroleum reservoirs. In the present study we focus on the role that organic labile sulfur compounds play in increasing the rate of TSR. A series of gold-tube hydrous pyrolysis experiments were conducted with n-octane and CaSO 4 in the presence of reduced sulfur (e.g. H 2S, S, organic S) at temperatures of 330 and 356 C under a constant confining pressure. The in-situ pH was buffered to 3.5 (6.3 at room temperature) with talc and silica. For comparison, three types of oil with different total S and labile S contents were reacted under similar conditions. The results show that the initial presence of organic or inorganic sulfur compounds increases the rate of TSR. However, organic sulfur compounds, such as 1-pentanethiol or diethyldisulfide, were significantly more effective in increasing the rate of TSR than H 2S or elemental sulfur (on a mole S basis). The increase in rate is achieved at relatively low concentrations of 1-pentanethiol, less than 1 wt% of the total n-octane, which is comparable to the concentration of organic S that is common in many oils (0.3 wt%). We examined several potential reaction mechanisms to explain the observed reactivity of organic LSC. First, the release of H 2S from the thermal degradation of thiols was discounted as an important mechanism due to the significantly greater reactivity of thiol compared to an equivalent amount of H 2S. Second, we considered the generation of olefines in association with the elimination of H 2S during thermal degradation of thiols because olefines are much more reactive than n-alkanes during TSR. In our experiments, olefines increased the rate of TSR, but were less effective than 1-pentanethiol and other organic LSC. Third, the thermal decomposition of organic LSC creates free-radicals that in turn might initiate a radical chain-reaction that creates more reactive species. Experiments involving radical initiators, such as diethyldisulfide and benzyldisulfide, did not show an increase in reactivity compared to 1-pentanethiol. Therefore, we conclude that none of these can sufficiently explain our observations of the initial stages of TSR; they may, however, be important in the later stages. In order to gain greater insight into the potential mechanism for the observed reactivity of these organic sulfur compounds during TSR, we applied density functional theory-based molecular modeling techniques to our system. The results of these calculations indicate that 1-pentanethiol or its thermal degradation products may directly react with sulfate and reduce the activation energy required to rupture the first S-O bond through the formation of a sulfate ester. This study demonstrates the importance of labile sulfur compounds in reducing the onset timing and temperature of TSR. It is therefore essential that labile sulfur concentrations are taken into consideration when trying to make accurate predictions of TSR kinetics and the potential for H 2S accumulation in petroleum reservoirs.

Amrani, Alon; Zhang, Tongwei; Ma, Qisheng; Ellis, Geoffrey S.; Tang, Yongchun

2008-06-01

37

Reactive uptake of organic compounds by liquid sulfuric acid.  

NASA Astrophysics Data System (ADS)

The uptake of several organic compounds by laboratory surrogates for tropospheric sulfuric acid particles were investigated by mass spectrometry and infrared reflection-absorption spectroscopy. Among the compounds studied were acetone [(CH_3)_2CO], 2,4-hexanedione [CH_3CO(CH_2)_2COCH_3, MBO], and 2-methyl-3-buten-2-ol [CH_2CHC(CH_3)_2OH]. Experiments were carried out on ultrathin sulfuric acid films (ca. 10-100 monolayer equivalents thick) as functions of organic partial pressure, temperature, and acid composition. Acetone uptake is irreversible for acids that contain >70 weight percent (wt. %) H_2SO4, with kinetics that are second-order in concentration of dissolved acetone. Hexanedione and MBO are irreversibly taken for all acid compositions investigated (60-96 wt. %), with first-order uptake kinetics. In all cases, the irreversible uptake is a consequence of sulfuric acid catalyzed reactions that lead to the formation of new C-C bonds. Implications of these results for heterogeneous tropospheric chemistry will be discussed.

Roberts, J.; Michelsen, R.

2003-04-01

38

Detecting endocrine disrupting compounds in water using sulfur-oxidizing bacteria  

Microsoft Academic Search

For the rapid and reliable detection of endocrine disrupting compounds in water, a novel toxicity detection methodology based on sulfur-oxidizing bacteria (SOB) has been developed. The methodology exploits the ability of SOB to oxidize elemental sulfur to sulfuric acid in the presence of oxygen. The reaction results in an increase in electrical conductivity (EC) and a decrease in pH. When

Steven W. Van Ginkel; Sedky H. A. Hassan; Sang-Eun Oh

2010-01-01

39

The interpretation of sulfur K-edge XANES spectra: a case study on thiophenic and aliphatic sulfur compounds.  

PubMed

Sulfur K-edge XANES has been measured for three sulfur model compounds, dibenzothiophene, dibenzothiophene sulfone, and aliphatic sulfur (DL-methionine). The spectra have been simulated with Density Functional Theory (DFT) by using a number of methods, including the half-core-hole approximation. Dipole transition elements were calculated and the transitions were convoluted with linearly increasing Gaussian functions in the first 20 eV of the near-edge region. In the case of dibenzothiophene, relaxation of the first excited states in the presence of the core-hole gave a further improvement. The theoretical results reproduce well the features of the spectra and give insight in the relation between geometric structure and molecular orbitals. Though DL-methionine and dibenzothiophene show a similar sharp rise of the white line, their molecular levels are quite different, pointing out the difficulties in finding useful "fingerprints" in the spectra for specific compounds. PMID:19296706

Mijovilovich, A; Pettersson, L G M; Mangold, S; Janousch, M; Susini, J; Salome, M; de Groot, F M F; Weckhuysen, B M

2009-03-26

40

Determination of sulfur compound distribution in petroleum by gas chromatography with a flame photometric detector  

SciTech Connect

A simulated distillation using a flame photometric detector (FPD) is reported for determining the boiling range distribution of sulfur-containing compounds in middle-to-heavy petroleum distillates. Its success is based on a new calibration method for the FPD involving converting all the sulfur-containing compounds to SO/sub 2/ before detection and linearizing the data. A single calibration equation is formulated expressing a uniform and linear relationship between detector response and sulfur concentration for the various types of sulfur compounds in petroleum. Consequently, the problems of handling the detector's nonlinearity and variance of response to different sulfur compounds are eliminated. The method is quantitative and applicable to petroleum distillates with a final boiling point of 1184 /sup 0/F (640 /sup 0/C) and greater than or equal to850 ppm by weight total sulfur content.

Bradley, C.; Schiller, D.J.

1986-12-01

41

Sulfur recovery process  

SciTech Connect

This paper describes a method for recovering sulfur from a process feed stream mixture of gases comprising sulfur-containing compounds including hydrogen sulfide using the Claus reaction to convert sulfur-containing compounds to elemental sulfur and crystallization to separate sulfur-containing compounds from a tail gas of the Claus reaction for further processing as a recycle stream. It comprises: providing a Claus feed stream containing a stoichiometric excess of hydrogen sulfide, the Claus feed stream including the process feed stream and the recycles stream; introducing the Claus feed stream and an oxidizing agent into a sulfur recovery unit for converting sulfur-containing compounds in the Claus feed stream to elemental sulfur; withdrawing the tail gas from the sulfur recovery unit; separating water from the tail gas to producing a dehydrated tail gas; separating sulfur-containing compounds including carbonyl sulfide from the dehydrated tail gas as an excluded material by crystallization and withdrawing an excluded material-enriched output from the crystallization to produce the recycle stream; and combining the recycle stream with the process feed stream to produce the Claus feed stream.

Hise, R.E.; Cook, W.J.

1991-06-04

42

Sulfur Kedge X-ray absorption spectroscopy of petroleum asphaltenes and model compounds  

Microsoft Academic Search

The utility of sulfur K-edge X-ray absorption spectroscopy for the determination and quantification of sulfur forms in petroleum asphaltenes has been investigated. Both X-ray absorption near edge structure (XANES) and extended X-ray absorption fine structure (EXAFS) spectra were obtained for a selected group of model compounds and for several petroleum asphaltene samples. For the model compounds the sulfur XANES was

Graham N. George; Martin L. Gorbaty

1989-01-01

43

Lunar sulfur  

NASA Astrophysics Data System (ADS)

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.

Kuck, David L.

44

Effect of Temperature Regime on the Removal of Sulfur Compounds.  

National Technical Information Service (NTIS)

The effect of the temperature regime in the adsorptive scrubbing of thermal-cracking gasoline is analyzed. Scrubbed stock quality is investigated and changes in the sulfur load of adsorbents in the specified regime are discussed.

L. G. Geraskina K. B. Chernysheva E. E. Nikitin

1974-01-01

45

Organo-sulfur compounds in sediments of the Puget Sound basin  

Microsoft Academic Search

Sediment samples from a variety of different environments were analyzed for organo-sulfur compounds (OSC) to provide the first characterization of the amounts and types of these compounds in sediments of the greater Puget Sound basin. A gas Chromatograph equipped with a sulfur specific flame photometric detector was used to quantify individual OSC. Compositions of OSC mixtures were essentially constant throughout

Timothy S. Bates; Roy Carpenter

1979-01-01

46

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

Microsoft Academic Search

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

G. Michael; R. Kadmi

2007-01-01

47

A Novel Method for Removing Sulfur Compounds from Light Oil by Molecular Recognition with ?-Cyclodextrin  

Microsoft Academic Search

Studies have been carried out aimed at recognizing ?-cyclodextrin as including sulfur compounds by competitive inclusion using phenolphthalein as a spectral probe. 1-Propanethiol was chosen as a model sulfur compound and the obtained results indicated that ?-CD could include 1-propanethiol and remove it from light oil. The time and the temperature of inclusion and the mass content of ?-CD in

Yan Sun; Daohong Xia; Yuzhi Xiang

2008-01-01

48

Laser spectroscopy on volatile sulfur compounds: possibilities for breath analysis.  

PubMed

There is an emerging interest in the detection of volatile sulfur compounds (VSCs) in the breath environment, given their biological relevance as potential signatures of several pathological conditions. Particularly, laser-based spectroscopic sensors are candidates for conducting accurate breath diagnostics in clinical settings. With these aims in mind, the current status of VSC sensing via laser absorption spectroscopy is reviewed in this paper. Attention has been focused on the most promising exhaled markers of pathological conditions, namely hydrogen sulfide, carbonyl sulfide, methanethiol, carbon disulfide and dimethyl sulfide. Details of the most relevant spectroscopic studies conducted on such molecules are presented, together with suggestions on the future direction of this challenging analytical field. PMID:21593551

Ciaffoni, L; Peverall, R; Ritchie, G A D

2011-05-19

49

Organic volatile sulfur compounds in inland aquatic systems  

SciTech Connect

The speciation, concentration, and fluxes of organic volatile sulfur compounds (VSCs) in a wide variety of inland aquatic systems wee studied. Dissolved VSCs were sparged from water samples, trapped cryogenically, and quantified by gas chromatograph equipped with a flame photometric detector. Species detected and mean surface water concentrations were: carbonyl sulfide (COS), 0.091-7.6 nM; methanethiol (MSH), undetected-180 nM; dimethyl sulfide (DMS), 0.48-1290 nM; carbon disulfide (CS[sub 2]), undetected-69 nM; dimethyl disulfide (DMDS), undetected-68 nM. The range in surface water concentrations of over five orders of magnitude was influenced principally by lake depth and sulfate concentration ([SO[sub 4][sup 2[minus

Richards, S.R.

1991-01-01

50

Measurement of total reduced sulfur compounds in ambient air  

SciTech Connect

Methods for the determination of total reduced sulfur (TRS) compounds in the ambient air based on coulometric detection (Philips Model PW 9700 analyzer) and thermal oxidation followed by detection using pulsed fluorescence (Teco Model 43 analyzer) have been evaluated. Analytical response factors, relative to H/sub 2/S, were determined for both the individual TRS compounds and compounds such as terpenes and carbonyl sulfide that may be a potential source of interference. The results for COS and terpenes indicate that in a typical monitoring situation normally encountered concentrations of these compounds are not expected to cause significant measurement bias. The results for the individual TRS compounds indicate that while variations in TRS composition are not a factor in assessing measurement bias for the thermal oxidation/pulsed fluorescence method, they are a factor for the Philips coulometric method; i.e., increasing positive measurement bias maybe introduced as the TRS composition shifts toward relatively less H/sub 2/S. Philips-Teco comparison data collected at a single site in the vicinity of three operating kraft pupil mills are compatible with these expectations. 8 references, 1 figure, 3 tables.

McQuaker, N.R.; Rajala, G.E.; Pengilly, D.

1986-05-01

51

Process for the hydrodesulfurization of natural gas containing organic sulfur compounds and oxygen  

SciTech Connect

Process is claimed for hydrodesulfurizing a gas comprising together methane, at least one organic sulfur compound and oxygen, characterized by the step of passing a mixture of said gas with a hydrogen containing gas on a palladium catalyst at a temperature of 300/sup 0/ to 450/sup 0/ C. The gas usually comprises at least 2 mg/Nm/sup 3/ of sulfur as organic sulfur and 0.05 to 2% by volume of oxygen.

Deschamps, A.; Cosyns, J.; Le Page, J.F.

1984-07-17

52

Role of reduced sulfur compounds in nutrition of Propionibacterium acnes.  

PubMed Central

In a study of the nutritional requirements of Propionibacterium acnes, acid hydrolyzed casein was shown to be the preferred nitrogen source in a glycerol-salts medium. Of 22 individual amino acids tested, only cysteine supported growth in the glycerol-salts medium. This indicated a requirement not only for amino nitrogen but also for reduced sulfur. In the presence of an auxiliary nitrogen source, thioglycolate or thiosulfate could replace sulfur-containing amino acids. The apparent requirement of P. acnes for reduced sulfur possibly could be satisfied in vivo by the constant availability of this substance in the form of sulfhydryl groups in the sebaceous follicle during keratinization. The relationship between P. acnes and its nutritional substrate may give this organism a selective advantage to exist in this ecological niche.

Nielsen, P A

1983-01-01

53

Role of reduced sulfur compounds in nutrition of Propionibacterium acnes.  

PubMed

In a study of the nutritional requirements of Propionibacterium acnes, acid hydrolyzed casein was shown to be the preferred nitrogen source in a glycerol-salts medium. Of 22 individual amino acids tested, only cysteine supported growth in the glycerol-salts medium. This indicated a requirement not only for amino nitrogen but also for reduced sulfur. In the presence of an auxiliary nitrogen source, thioglycolate or thiosulfate could replace sulfur-containing amino acids. The apparent requirement of P. acnes for reduced sulfur possibly could be satisfied in vivo by the constant availability of this substance in the form of sulfhydryl groups in the sebaceous follicle during keratinization. The relationship between P. acnes and its nutritional substrate may give this organism a selective advantage to exist in this ecological niche. PMID:6833481

Nielsen, P A

1983-02-01

54

Discrimination between 34S and 32S during bacterial metabolism of inorganic sulfur compounds.  

PubMed Central

Sulfur isotope effects during the oxidation of thiosulfate by Thiobacillus versutus were found to be negligible. This result is considered in relation to other oxidative and reductive processes to assess which reactions are most likely to control the isotopic compositions of sulfur compounds in microbial sulfureta.

Fry, B; Cox, J; Gest, H; Hayes, J M

1986-01-01

55

Biogenic Sulfur Compounds in Coastal Atmospheres of North Carolina.  

National Technical Information Service (NTIS)

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 ...

D. R. Hitchcock L. L. Spiller W. E. Wilson

1978-01-01

56

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

SciTech Connect

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.

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

2013-01-01

57

Metal phosphate reduction in the presence of gaseous sulfur compounds  

SciTech Connect

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.

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

1992-05-20

58

Volatile Sulfur Compounds as a Predictor for Esophagogastroduodenal Mucosal Injury  

PubMed Central

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.

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

2008-01-01

59

Sulfur Chemiluminescence Detection Compared to Sulfur Flame Photometric Detection.  

National Technical Information Service (NTIS)

Detection of compounds containing sulfur heteratom is traditionally accomplished using flame photometric detection (FPD). Sulfur chemiluminescence detection (SCD) is an alternative to FPD. This report compares the FPD with two SCD configurations using var...

M. W. Elizy L. G. Janes

1998-01-01

60

Sulfuric Acid on Europa's Surface and the Radiolytic Sulfur Cycle  

NASA Astrophysics Data System (ADS)

Galileo infrared spectra of Europa's surface show distorted water bands that have been attributed to hydrated evaporite salts (McCord et al., J. Geophys. Res. 104, 11827, 1999) or to the scattering properties of ice (Dalton and Clark, Bull. Am. Astron. Soc. 30, 1081, 1998). Using new laboratory spectra, we show that hydrated sulfuric acid can explain Europa's spectra and further show that this species is a product of radiolysis. Sulfuric acid on Europa occurs as the radiolytically stable octahydrate and hemihexahydrate and is a major surface component, along with water ice. The sulfuric acid concentration correlates spatially with Europa's visually dark material, which we identify as radiolytically altered sulfur polymers. Radiolysis by incident jovian plasma continuously cycles sulfur between three chemical reservoirs: sulfuric acid, polymerized sulfur, and sulfur dioxide, with the acid being about 50 times more abundant than the other forms because of the stability of the sulfate anion under irradiation. The original source of sulfur may be incident iogenic sulfur ions or endogenic sulfur compounds that are altered by radiolysis. Geological processes can bury and redistribute the sulfurous material, producing a sulfur-rich crust and a non-uniform surface distribution. The low melting point of sulfuric acid and its ability to supercool may facilitate geological processes. Europa's magnetic response may be influenced by the electrical conductivity of sulfuric acid.

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

1999-09-01

61

Effects of sulfur-containing compounds on the growth and methane production of acclimated-mixed methanogens  

Microsoft Academic Search

A variety of sulfur-containing compounds were investigated for use as medium reductant and sulfur sources for growth of the acclimated-mixed methanogens. In Hungate tube cultures, the optimum concentrations of sulfur compounds for growth and CH4 formation were sulfide, 0.9 mmol; cysteine, 3.6 mmol; thiosulfate, 0.675 mmol; elemental sulfur (S0), 0.45 gl?1; glutathione, 2.5 mmol; SO42?, 3.6 mmol; SO32?, 0.9 mmol;

Zhen Ya Zhang; Takaaki Maekawa

1996-01-01

62

Liquid-vapor equilibrium under elevated pressures in the systems formed by pentanes with sulfur compounds  

SciTech Connect

The possibility of removing sulfur compounds from the pentane fraction was studied. Experimental data obtained on liquid-vapor equilibrium in the system formed by pentanes with sulfur compounds under elevated pressures is presented. Vapor-liquid equilibrium was studied with the aid of a modified Swietoslawski apparatus made of stainless steel. Experimental data on phase equilibria of binary mixtures in the system studied are presented. The compositions and boiling points of binary azeotropes at the pressures studied are also presented.

Shakirzyanov, R.G.; Telyakov, E.S.; Serafimov, L.A.

1982-10-20

63

A study of the adsorption of thiophenic sulfur compounds using flow calorimetry  

Microsoft Academic Search

Selective adsorption of sulfur compounds from gasoline and diesel fuel has potential to produce ultra clean fuels for on-board fuel cell applications and also to meet the upcoming legislation for clean fuels. Removal of thiophenic sulfur compounds in a hexadecane solution using commercial zeolites, NaY, USY, HY and 13X, has been investigated by adsorption and flow calorimetry techniques. The S

Flora T. T. Ng; Ataur Rahman; Tomotsugu Ohasi; Ming Jiang

2005-01-01

64

Odorous Sulfur Compounds Emitted during Production of Compost Used as a Substrate in Mushroom Cultivation  

PubMed Central

Large-scale composting facilities are known to cause environmental problems, mainly through pungent air emitted by composting material. In air samples taken above stacks set up to prepare compost used as a substrate in mushroom cultivation, several volatile compounds were identified by means of the coupled techniques of gas chromatography and mass spectrography. Among the compounds identified, sulfur-containing compounds [H2S, COS, CH3SH, CS2, (CH3)2S, (CH3)2S2, and (CH3)2S3] are the most conspicuous in causing a nuisance. Quantification of these compounds was performed by concentrating a relatively small air sample on Tenax GC. The sampling method appeared to be very useful under field conditions. During the composting process, the concentration of the volatile sulfur compounds in emitted air ranged from 1 to 35 ?mol/m3. The highest concentrations were obtained at the end of the outdoor process. Total sulfur emission amounted to 8.3 mg of sulfur per kg (fresh weight) of compost. The end product still contained 2.58 g of sulfur per kg (fresh weight) of compost. Suggestions about the origin of the volatile sulfur compounds are made.

Derikx, P. J. L.; Op Den Camp, H. J. M.; van der Drift, C.; van Griensven, L. J. L. D.; Vogels, G. D.

1990-01-01

65

Compounds with mixed and intermediate sulfur valences in pyrite from the Amelia Mine, Southwest Wisconsin  

NASA Astrophysics Data System (ADS)

Compounds with mixed and intermediate sulfur valences form cloudy small inclusions in banded pyrite and 2 4 mm large rounded aggregates in pyrite stalactites. Such areas under high magnification of SEM appear to be a mixture of FeS2 with FeS2O3. Some of the microareas of 40 50 ?m are homogeneous and can be identified by reflected light microscopy, microprobe and soft X-ray spectroscopy as Fe-thiosulphate, FeS2O3 or (Fe, Pb)2S3O7 with this compound having one sulfur -2 and two sulfurs +6. The intermediate sulfur compounds are enriched in Pb, Ni, Co and As.

Kucha, H.; Barnes, H. L.

1995-02-01

66

A solvent system to provide selective removal of sulfur compounds  

SciTech Connect

Energy costs and SRU inefficiencies resulting from utilization of low strength MEA technology induced a large refinery to convert to MDEA. One of the seven product streams being treated required extremely low carbonyl sulfide in the treated product. This required careful consideration in making the decision to convert. However, the conclusions were that the advantages outweighed the disadvantages. When the initial converted operations verified a need to improve the carbonyl sulfide removal, GAS/SPEC Tech Service produced an innovative solution which allowed for efficient operation at acceptable COS specification, lower energy utilization, reduced solvent losses, and improved sulfur recovery unit operation.

Pearce, R.L.; Bacon, T.R.

1986-01-01

67

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

PubMed

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 activity was not inhibited by these uncouplers. Valinomycin did not inhibit the oxidation of sulfur compounds. NaCl stimulated the sulfur- and sulfite-oxidizing activities in resting cells but not in cell-free extracts. The tetrathionate-oxidizing activity in resting cells was slightly stimulated by NaCl, whereas it did not influence the thiosulfate-oxidizing activity. Sulfide oxidation was biphasic, suggesting the formation of intermediate sulfur. The initial phase of sulfide oxidation was not affected by NaCl, whereas the subsequent oxidation of sulfur in the second phase was Na+-dependent. A model is proposed for the role of NaCl in the metabolism of reduced sulfur compounds in A. thiooxidans strain SH. PMID:15375674

Kamimura, Kazuo; Higashino, Emi; Kanao, Tadayoshi; Sugio, Tsuyoshi

2004-09-16

68

Ab initio study of hypervalent sulfur hydrides as model intermediates in the interconversion reactions of compounds containing sulfur-sulfur bonds  

SciTech Connect

Ab initio MO calculations involving the 4-31G* basis set have been used to predict the equilibrium geometries of the hypervalent sulfur hydrides H/sub 2/SS, (HS)/sub 2/SS, H/sub 2/S(SH)/sub 2/, H/sub 2/S(SSH)/sub 2/, and the cyclic H/sub 4/S/sub 4/. The energy changes in their formation from appropriate sulfanes H/sub 2/S/sub n/ (n = 1-4) have been studied with the 6-31G* basis set including the correction for the electron correlation by the second- and third-order Moeller-Plesset perturbation theory. The results are used to discuss the possible pathways in the interconversion reactions between various sulfur compounds containing cumulated SS bonds, for example, the formation of S/sub 7/ from S/sub 8/ for which hypervalent intermediates have been proposed recently. Comparison with experimental evidence is made whenever possible.

Laitinen, R.S.; Pakkanen, T.A.; Steudel, R.

1987-02-04

69

Evaluation of occupational exposure to sulfur compounds in paper pulp kraft mills.  

PubMed

A study was carried out to provide a comprehensive profile of sulfur gas concentrations to which workers are exposed during the manufacture of paper pulp by the kraft process. Methods currently available--including colorimetric tubes, direct-reading monitors, and gas chromatographic methods--were compared. Gas chromatography is the only technique able to reliably measure individual sulfur gases. However, the necessity of using a gas sampling bag renders this technique inappropriate for personal monitoring. A strategy to evaluate occupational exposure was developed, based on fluctuations in workplace concentrations and the time profile of worker activities. In most samples, only three sulfur products were detected: dimethyl sulfide, methyl mercaptan, and hydrogen sulfide. Concentrations varied as a function of time and location and are correlated to process and equipment-operation variables. Using the proposed strategy, it was demonstrated that workers in the pulp and paper industry can be exposed to significant concentrations of sulfur compounds. PMID:2382641

Goyer, N

1990-07-01

70

Anti-Inflammatory Activity of Sulfur-Containing Compounds from Garlic  

PubMed Central

Abstract We identified four anti-inflammatory sulfur-containing compounds from garlic, and their chemical structures were identified as Z- and E-ajoene and oxidized sulfonyl derivatives of ajoene. The sulfur compounds inhibited the production of nitric oxide (NO) and prostaglandin E2 (PGE2) and the expression of the pro-inflammatory cytokines tumor necrosis factor-?, interleukin-1?, and interleukin-6 in lipopolysaccharide (LPS)-activated macrophages. Western blotting and reverse transcriptionpolymerase chain reaction analysis demonstrated that these sulfur compounds attenuated the LPS-induced expression of the inducible NO synthase (iNOS) and cyclooxygenase-2 (COX-2) proteins and mRNA. Moreover, these sulfur-containing compounds suppressed the nuclear factor-?B (NF-?B) transcriptional activity and the degradation of inhibitory-?B? in LPS-activated macrophages. Furthermore, we observed that they markedly inhibited the LPS-induced phosphorylations of p38 mitogen-activated protein kinases and extracellular signal-regulated kinases (ERK) at 20??M. These data demonstrate that the sulfur compounds from garlic, (Z, E)-ajoene and their sulfonyl analogs, can suppress the LPS-induced production of NO/PGE2 and the expression of iNOS/COX-2 genes by inhibiting the NF-?B activation and the phosphorylations of p38 and ERK. Taken together, these data show that Z- and E-ajoene and their sulfonyl analogs from garlic might have anti-inflammatory therapeutic potential.

Lee, Da Yeon; Li, Hua; Lim, Hyo Jin; Lee, Hwa Jin; Jeon, Raok

2012-01-01

71

Efficiency of short, thick-film capillary columns in gas chromatography with sulfur chemiluminescence detector for the separation of sulfur compoundsa best performance study  

Microsoft Academic Search

SummaryShort, thick-film capillary columns can solve most of the routine applications of gas chromatography in much shorter time\\u000a than packed columns. A theoretical and experimental study shows the contribution of various factors involved and permits optimization\\u000a of conditions for the separation of sulfur compounds with good resolution and shortened analysis time, using gas chromatography\\u000a coupled with a sulfur chemiluminescence detector.

Y.-C. Chen; B. S. Inbaraj; J.-G. Lo

1999-01-01

72

Sulfur Extended Asphalt Availability of Sulfur.  

National Technical Information Service (NTIS)

This report assesses the availability and pricing of sulfur with respect to sulfur extended asphalt paving mixtures. The assessment includes a review of past and current trends as well as sulfur estimates up to the year 2000 for the United States and spec...

J. P. Mahoney M. K. Loose J. A. Larry

1982-01-01

73

Sulfuric acid-sulfur heat storage cycle  

DOEpatents

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.

Norman, John H. (LaJolla, CA)

1983-12-20

74

Retrofitted Biotrickling Filters for Odor, VOC, H2S and Reduced Sulfur Compound Emission Control  

Microsoft Academic Search

This paper evaluates treatment of odorous compounds (hydrogen sulfide, reduced sulfur compounds, VOCs, ammonia, and total odor) in wet chemical scrubbers that were converted to biotrickling filters at the Orange County Sanitation District (OCSD), California. Results of over two years of continuous operation in five biotrickling filters are discussed. The biotrickling filters were usually operated at a gas contact time

Marc A. Deshusses; Vladimir Kogan; David Gabriel; Johannes M. Strauss; Jeffrey Brown; Edward Torres

75

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

DOEpatents

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.

Siriwardane, Ranjan

1999-09-30

76

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

DOEpatents

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.

Siriwardane, Ranjani

2004-06-01

77

Reduction of Sulfur Compounds in the Sediments of a Eutrophic Lake Basin  

PubMed Central

Concentrations of various sulfur compounds (SO42?, H2S, S0, acid-volatile sulfide, and total sulfur) were determined in the profundal sediments and overlying water column of a shallow eutrophic lake. Low concentrations of sulfate relative to those of acid-volatile sulfide and total sulfur and a decrease in total sulfur with sediment depth implied that the contribution of dissimilatory sulfur reduction to H2S production was relatively minor. Addition of 1.0 mM Na235SO4 to upper sediments in laboratory experiments resulted in the production of H235S with no apparent lag. Kinetic experiments with 35S demonstrated an apparent Km of 0.068 mmol of SO42? reduced per liter of sediment per day, whereas tracer experiments with 35S indicated an average turnover time of the sediment sulfate pool of 1.5 h. Total sulfate reduction in a sediment depth profile to 15 cm was 15.3 mmol of sulfate reduced per m2 per day, which corresponds to a mineralization of 30% of the particulate organic matter entering the sediment. Reduction of 35S0 occurred at a slower rate. These results demonstrated that high rates of sulfate reduction occur in these sediments despite low concentrations of oxidized inorganic compounds and that this reduction can be important in the anaerobic mineralization of organic carbon.

Smith, Richard L.; Klug, Michael J.

1981-01-01

78

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

SciTech Connect

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.

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

1992-09-01

79

Contribution of sulfuric acid and oxidized organic compounds to particle formation and growth  

NASA Astrophysics Data System (ADS)

Lack of knowledge about the mechanisms underlying new particle formation and their subsequent growth is one of the main causes for the large uncertainty in estimating the radiative forcing of atmospheric aerosols in global models. We performed chamber experiments designed to study the contributions of sulfuric acid and organic vapors to the formation and early growth of nucleated particles. Distinct experiments in the presence of two different organic precursors (1,3,5-trimethylbenzene and ?-pinene) showed the ability of these compounds to reproduce the formation rates observed in the low troposphere. These results were obtained measuring the sulfuric acid concentrations with two chemical ionization mass spectrometers confirming the results of a previous study which modeled the sulfuric acid concentrations in presence of 1,3,5-trimethylbenzene. New analysis methods were applied to the data collected with a condensation particle counter battery and a scanning mobility particle sizer, allowing the assessment of the size resolved growth rates of freshly nucleated particles. The effect of organic vapors on particle growth was investigated by means of the growth rate enhancement factor (?), defined as the ratio between the measured growth rate in the presence of ?-pinene and the kinetically limited growth rate of the sulfuric acid and water system. The observed ? values indicate that the growth is already dominated by organic compounds at particle diameters of 2 nm. Both the absolute growth rates and ? showed a strong dependence on particle size, supporting the nano-Khler theory. Moreover, the separation of the contributions from sulfuric acid and organic compounds to particle growth reveals that the organic contribution seems to be enhanced by the sulfuric acid concentration. Finally, the size resolved growth analysis indicates that both condensation of oxidized organic compounds and reactive uptake contribute to particle growth.

Riccobono, F.; Rondo, L.; Sipil, M.; Barmet, P.; Curtius, J.; Dommen, J.; Ehn, M.; Ehrhart, S.; Kulmala, M.; Krten, A.; Mikkil, J.; Paasonen, P.; Petj, T.; Weingartner, E.; Baltensperger, U.

2012-10-01

80

Contribution of sulfuric acid and oxidized organic compounds to particle formation and growth  

NASA Astrophysics Data System (ADS)

Lack of knowledge about the mechanisms underlying new particle formation and their subsequent growth is one of the main causes for the large uncertainty in estimating the radiative forcing of atmospheric aerosols in global models. We performed chamber experiments designed to study the contributions of sulfuric acid and organic vapors to formation and to the early growth of nucleated particles, respectively. Distinct experiments in the presence of two different organic precursors (1,3,5-trimethylbenzene and ?-pinene) showed the ability of these compounds to reproduce the formation rates observed in the low troposphere. These results were obtained measuring the sulfuric acid concentrations with two Chemical Ionization Mass Spectrometers confirming the results of a previous study which modeled the sulfuric acid concentrations in presence of 1,3,5-trimethylbenzene. New analysis methods were applied to the data collected with a Condensation Particle Counter battery and a Scanning Mobility Particle Sizer, allowing the assessment of the size resolved growth rates of freshly nucleated particles. The effect of organic vapors on particle growth was investigated by means of the growth rate enhancement factor (?), defined as the ratio between the measured growth rate in the presence of ?-pinene and the kinetically limited growth rate of the sulfuric acid and water system. The observed ? values indicate that the growth is dominated by organic compounds already at particle diameters of 2 nm. Both the absolute growth rates and ? showed a strong dependence on particle size supporting the nano-Khler theory. Moreover, the separation of the contributions from sulfuric acid and organic compounds to particles growth reveals that the organic contribution seems to be enhanced by the sulfuric acid concentration. The size resolved growth analysis finally indicates that both condensation of oxidized organic compounds and reactive uptake contribute to particle growth.

Riccobono, F.; Rondo, L.; Sipil, M.; Barmet, P.; Curtius, J.; Dommen, J.; Ehn, M.; Ehrhart, S.; Kulmala, M.; Krten, A.; Mikkil, J.; Petj, T.; Weingartner, E.; Baltensperger, U.

2012-05-01

81

Volatile sulfur compounds in human expiration after eating raw or heat-treated garlic.  

PubMed

Volatile sulfur compounds arising from grated raw or heat-treated garlic in both in-vitro and in-vivo tests were gas-chromatographically analyzed. In in-vitro tests, the head-space vapor gas from garlic in a vial was analyzed. It was clarified that allyl mercaptan arising from raw garlic decreased with the passage of time and other volatile low-molecular sulfur compounds (LMSC) did not show remarkable changes. The change of LMSC from heat-treated garlic was also studied. Methyl mercaptan and allyl mercaptan from heat-treated garlic gradually increased to some extent. On the other hand, the quantities of somewhat high-molecular sulfur compounds (HMSC) were much less in heat-treated garlic compared to those of raw garlic. These compounds increased till approx. 60 min and then decreased gradually. In in-vivo tests, human expiration after eating garlic was analyzed. Allyl mercaptan, methyl mercaptan and allyl methyl sulfide in LMSC were detected in significant amounts. The quantities of these compounds arising from heat-treated garlic were smaller than those from raw garlic. These compounds had the tendency of decreasing with the passage of time. On the other hand, almost no HMSC was detected in both raw and heat-treated garlic. By sensory testing, raw garlic showed a stronger smell than heat-treated garlic in both in-vitro and in-vivo tests. GC analysis exhibited higher values of volatile sulfur compounds in raw garlic. That is, the higher the volatile sulfur compound level, the stronger the garlic flavor or malodor. PMID:10450562

Tamaki, T; Sonoki, S

1999-04-01

82

Volcanic sulfur  

NASA Astrophysics Data System (ADS)

Although I may be overly demanding in expecting a member of the Eos staff to be familiar with recent articles in AGU journals, I am moved to make a mild protest concerning attribution in the Volcanic Sulfur Dynamics news item by Mario E. Godinez (Eos, June 14, 1983, p. 411).Since the news story stated that an important result of the RAVE experiment was to estimate the SO2 flux from Mount St. Helens on just one day, I must point out that both my research group and USGS scientists have monitored the emissions from Mount St. Helens and estimated SO2 (and other) fluxes over extended periods of time. Our results, which were based on in situ airborne measurements carried out over a period of a year, include estimates of the flux rates of SO2, H2S, H2O, sulfates, halides, and various other particles, prior to, during, and after the explosive eruption of Mount St. Helens on May 18, 1980 [Hobbs et al., 1983]. The USGS measurements, which are made remotely through use of an airborne correlation spectrometer, also commenced in 1980 a n d have provided data several times a week since that time [Casadevall et al., 1981]. We have also estimated the fluxes of various materials (including SO2) from eight other volcanos [Radke et al.., 1976; Stith et al.., 1978; Radke, 1982].

Hobbs, Peter V.

83

The effects of biodegradation and water washing on sulfur compound speciation in crude oils from the Bolivar Coastal Fields  

SciTech Connect

A series of crude oils from a partially and heavily biodegraded reservoir were analyzed fro sulfur compound speciation by x-ray absorption spectroscopy. The most reasonable explanation of the data is that they represent a maturity sequence. There is no strong evidence that biodegradation or water washing produce any major changes in sulfur compound speciation. 9 refs., 1 fig., 1 tab.

Manowitz, B.; Jeon, Y.

1991-08-01

84

The effects of biodegradation and water washing on sulfur compound speciation in crude oils from the Bolivar Coastal Fields  

Microsoft Academic Search

A series of crude oils from a partially and heavily biodegraded reservoir were analyzed fro sulfur compound speciation by x-ray absorption spectroscopy. The most reasonable explanation of the data is that they represent a maturity sequence. There is no strong evidence that biodegradation or water washing produce any major changes in sulfur compound speciation. 9 refs., 1 fig., 1 tab.

B. Manowitz; Y. Jeon

1991-01-01

85

VOLATILE SULFUR COMPOUNDS CONTRIBUTE TO THE IRRADIATION-INDUCED OFF-ODOR IN ORANGE JUICE  

Technology Transfer Automated Retrieval System (TEKTRAN)

Ionizing radiation is an effective technology that inactivates foodborne pathogens in fruit juices and other foods. Some studies have shown that ionizing radiation can cause the development of an off-odor, and volatile sulfur compounds have been suggested to be a possible cause of the off-odor. Ho...

86

Effect of Sulfur Compound Addition on Hydrodesulfurization of Coker Gas Oil  

Microsoft Academic Search

To clarify the effect of sulfur compound addition on catalytic activity and catalyst deactivation, hydrodesulfur- ization (HDS) of coker gas oil (CGO) was carried out over demetallation catalysts, metal tolerant desulfurization catalyst and desulfurization catalysts. The initial HDS constant and catalyst life were slightly improved by the addition of 1000 ppm of dimethyldisulfi de (DMDS), probably by the prevention of

Takeshige Takahashi; Yoshiko Harada; Masaru Ueki; Takami Kai

2006-01-01

87

Oral malodor in children and volatile sulfur compound- producing bacteria in saliva: preliminary microbiological investigation  

Microsoft Academic Search

Purpose: This study examined and compared levels of salivary bacteria which produced volatile sulfur compounds (VSC) in young children with and without oral malodor. Methods: Clinic populations of children aged two to seven years, whose parents presented with an unsolicited major complaint of oral malodor in their child (OM+), or aged-matched controls in whom oral malodor was not detected by

Fariba Paryavi-Gholami; Glenn E. Minah; Foo Turng

1999-01-01

88

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

ERIC Educational Resources Information Center

|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.|

Chasteen, Thomas G.; Bentley, Ronald

2004-01-01

89

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

Microsoft Academic Search

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

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

2012-01-01

90

Influence of anxiety on the production of oral volatile sulfur compounds  

Microsoft Academic Search

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

Caroline Morini Calil; Fernanda Klein Marcondes

2006-01-01

91

Electrochemical studies of gold ore processing wastewater containing cyanide, copper, and sulfur compounds  

Microsoft Academic Search

The electrochemistry of real gold ore processing wastewater solutions from copper sulfide containing gold ore has been investigated. Analysis shows that the wastewater contains a range of sulfur compounds in various oxidation states from sulfide to sulfate. The electrochemical characteristics of the gold ore processing wastewater were evaluated using rotating disk, cyclic voltammetric, polarization and preparative electrolysis studies. The solutions

S. C. Cheng; M. Gattrell; T. Guena; B. MacDougall

2006-01-01

92

ENAMAP-2 AIR POLLUTION MODEL FOR LONG-RANGE TRANSPORT OF SULFUR AND NITROGEN COMPOUNDS  

EPA Science Inventory

This report describes the Eastern North American Model for Air Pollution (ENAMAP-2), which simulates the long-range transport and deposition of air pollutants across eastern North America. There are two versions of the model-one for sulfur compounds (ENAMAP-2S) and one for nitrog...

93

A review of volatile sulfur-containing compounds from terrestrial plants: biosynthesis, distribution and analytical methods  

Microsoft Academic Search

This review includes 554 volatile sulfur-containing compounds (VSCs) that have been reported from 43 terrestrial plant families until and including 2010. This review deals with extraction and analytical methods for VSCs, distribution of VSCs among plants, biosynthesis and other important aspects of this class of natural products. It has been shown that some classes of VSCs, specifically those in certain

M. Iranshahi

2012-01-01

94

Microwave Remote Sensing of the Temperature and Distribution of Sulfur Compounds in the Lower Atmosphere of Venus  

Microsoft Academic Search

A dual-wavelength radio frequency observation of Venus was performed on April 5, 1996 with the Very Large Array to investigate potential variations in the vertical and horizontal distribution of temperature and the sulfur compounds sulfur dioxide (SO2) and sulfuric acid vapor (H2SO4(g)) in the Venus atmosphere. Brightness temperature maps were produced which feature significantly darkened polar regions compared to the

J. M. Jenkins; M. A. Kolodner; B. J. Butler; S. H. Suleiman; P. G. Steffes

2001-01-01

95

Microwave Remote Sensing of the Temperature and Distribution of Sulfur Compounds in the Lower Atmosphere of Venus  

Microsoft Academic Search

A multi-wavelength radio frequency observation of Venus was performed on April 5, 1996, with the Very Large Array to investigate potential variations in the vertical and horizontal distribution of temperature and the sulfur compounds sulfur dioxide (SO2) and sulfuric acid vapor (H2SO4(g)) in the atmosphere of the planet. Brightness temperature maps were produced which feature significantly darkened polar regions compared

Jon M. Jenkins; Marc A. Kolodner; Bryan J. Butler; Shady H. Suleiman; Paul G. Steffes

2002-01-01

96

Effects on plants of sulfur pollutants from coal combustion  

Microsoft Academic Search

Sulfur dioxide, the most widely known form of sulfur pollution, is highly toxic to plant life, even at levels lower than the current Federal Ambient Air Quality Standard. Sulfur dioxide can also form sulfates, sulfites, and liquids such as sulfurous acid and sulfuric acid, all of which can be toxic to plant and animal life. Most sulfur compounds also acidify

1978-01-01

97

Investigating the antioxidant properties of oxo-sulfur compounds on metal-mediated DNA damage  

Microsoft Academic Search

The organosulfur compounds allicin, methionine and methylcysteine protect against metal- mediated oxidative DNA damage, but few studies have determined the antioxidant behaviour of the oxo-sulfur derivatives of these compounds. Gel electrophoresis experiments were performed to determine the ability of MetSO, MeCysSO, MMTS, MePhSO and Me2SO2 to inhibit copper- and iron-mediated DNA damage. Under these conditions, MetSO and MeCysSO significantly inhibit

RIA R. RAMOUTAR; JULIA L. BRUMAGHIM

2008-01-01

98

Retention parameters of sulfur-containing and aromatic compounds of petroleum in liquid chromatography on silica gel  

SciTech Connect

The authors present results from determinations of the retention parameters of sulfur-containing compounds, specifically thiophene, benzothiophene, thiophane, dibutyl sulfide, and diphenyl sulfide. The retention time of the sulfur compounds was determined in a chromatograph that is described, with a transport detector and dielectric constant detector. ASK silica gel was used as the adsorbent. The method developed for calculating the retention parameters of sulfur-containing and aromatic compounds in petroleum crudes and products offers a means for a reliable identification of the position of these compounds on chromatograms.

Khairudinov, I.R.; Kolbin, M.A.

1986-01-01

99

Determination of sulfur compounds in coal by mass spectrometry, correlated with XANES and XPS  

SciTech Connect

The objective of this study is to identify important organic sulfur-containing compounds in the Argonne Premium Coals and in selected, separated coal macerals. In-source, desorption/pyrolysis high resolution mass spectrometry is being used to characterize the volatile species of whole coals, macerals, and their extracts. To examine the possibility of secondary reactions and undesirable selectivity, the MS data is compared to data from direct techniques, XANES and XPS. The MS results con-elate very well which supports the suggestion that the species seen are indigenous to the original sample. Therefore, specific structural assignments to the sulfur species can be made. Quantitative speciation of organic sulfur in coals has been accomplished by both XANES and XPS with what appears to be good reliability. Mass spectrometry approaches provide more detailed molecular information, but suffer from problems with sampling. In the past we have found it difficult to isolate aliphatic sulfur compounds by thermal desorption or pyrolysis due to their thermal transformation to aromatic species. However, recently we have found that with in-source pyrolysis the occurrence of secondary reactions is reduced significantly. Results from both a selected setof the Argonne Premium Coal Samples and a set of three macerals from the Listen-Stockton coal (APCS 7) are discussed.

Winans, R.E.; Melnikov, P.E.; Dyrkacz, G.R.; Bloomquist, C.A.A. [Argonne National Lab., IL (United States); Gorbaty, M.L.; Kelemen, S.R.; George, G.N. [Exxon Research and Engineering Co., Annandale, NJ (United States)

1993-03-01

100

Determination of relative concentrations of primary and secondary organics and speciation of sulfur compounds by thermal analysis and photoelectron spectroscopy  

SciTech Connect

Carbon-, sulfur-, and nitrogen-containing particles account for most of the anthropogenic aerosol particle burden. Methodology developed to quantitate the amounts of primary and secondary particulate carbon data are presented on speciation of sulfur compounds by a novel approach using thermal analysis and photoelectron spectroscopy (ESCA).

Novakov, T.; Dod, R.L.; Gundel, L.A.; Hansen, A.D.A.

1981-04-01

101

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...

102

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...

103

SYNTHESIS AND BIOLOGICAL ACTIVITY OF SULFUR COMPOUNDS SHOWING STRUCTURAL ANALOGY WITH COMBRETASTATIN A-4.  

PubMed

We extended our previous exploration of sulfur bridges as bioisosteric replacements for atoms forming the bridge between the aromatic rings of combretastatin A-4. Employing coupling reactions between 5-iodo-1,2,3-trimethoxybenzene and substituted thiols, followed by oxidation to sulfones with m-CPBA, different locations for attaching the sulfur atom to ring A through the synthesis of nine compounds were examined. Antitubulin activity was performed with electrophoretically homogenous bovine brain tubulin, and activity occurred with the 1,2,3-trimethoxy-4-[(4-methoxyphenyl)thio]benzene (12), while the other compounds were inactive. The compounds were also tested for leishmanicidal activity using promastigote forms of Leishmania braziliensis (MHOM/BR175/M2904), and the greatest activity was observed with 1,2,3-trimethoxy-4-(phenylthio)benzene (10) and 1,2,3-trimethoxy-4-[(4-methoxyphenyl) sulfinyl]benzene (15). PMID:23766547

Dos Santos, Edson Dos A; Prado, Paulo C; de Carvalho, Wanderley R; de Lima, Ricardo V; Beatriz E, Adilson; de Lima, Dnis P; Hamel, Ernest; Dyba, Marzena A; Albuquerque, Sergio

2013-02-01

104

Sulfur in the atmosphere  

Microsoft Academic Search

In unpolluted areas sulfur occurs primarily in three compounds, SO\\/sup 2 -\\/ in aerosols and SO and HS in gas. Sources of SO\\/sup 2 -\\/ are the ocean, the soil, and the oxidation of the gaseous compounds. A considerable fraction of the SO is of anthropogenic origin. As measurements in polluted and unpolluted areas indicate, most of the HS seems

C. E. Junge

1960-01-01

105

Sulfur specific chromatography using hydrogenalysis  

SciTech Connect

A totally sulfur specific chromatographic detector is described based on the differential colorimetry of lead acetate tape. Its output is linear with concentration, and has no response to compounds other than sulfur compounds. These characteristics are particularly advantageous when analyzing hydrocarbon gases and light hydrocarbon liquids for low part per million and part per billion concentrations of sulfur compounds. As each particular sulfur species is eluted from a chromatograph column it is mixed with hydrogen and swept into a tube furnace. In the furnace, this sulfur peak is changed into a corresponding hydrogen sulfide peak. The corresponding hydrogen sulfide peak is detected by a lead acetate tape based hydrogen sulfide analyzer. Theory of operation, performance characteristics, and applicability of this type of detector are discussed.

Szinyei, W.J. (Tracor Atlas, Inc., 9441 Baythorne Dr., Houston, TX (US))

1988-01-01

106

Defluorination of organofluorine sulfur compounds by Pseudomonas sp. strain D2  

SciTech Connect

Little is known of the potential for biodegradation of fluorinated sulfonates. Because of the apparent stability of fluorinated organics, their bioactivity, and their potential for accumulation in the environment, it is important to understand their environmental fate and the mechanisms by which they might be degraded. To evaluate this potential, the following model compounds were selected: difluoromethane sulfonate (DFMS), trifluoromethane sulfonate (TFMS), 2,2,2-trifluoroethane sulfonate (TES), perfluorooctane sulfonate (PFOS), and 1H,1H,2H,2H-perfluorooctane sulfonate (H-PFOS). A laboratory isolate designated Pseudomonas sp. strain D2 completely defluorinated DFMS under aerobic sulfur-limiting conditions in a defined mineral medium. Strain D2 utilized DFMS as the sole source of sulfur, but not as a source of carbon or energy. DFMS utilization was inhibited by other forms of sulfur, and noncompetitive inhibition kinetics were observed, with K{sub i}-values of 3--4 {micro}M for sulfate, sulfite, methane sulfonate, and cystine. Strain D2 was subsequently used to evaluate degradation of other fluorinated sulfonates. Growth and defluorination were only observed for those compounds containing hydrogen (TES and H-PFOS). TFMS and PFOS were not degraded. TES was completely defluorinated, and H-PFOS was partially defluorinated. No volatile transformation products were detected for TES or DFMS, but six volatile products were detected for H-PFOS. All of the volatile products contained oxygen and fluorine, but not sulfur. This is the first report of defluorination of fluorinated sulfonates, a linkage between sulfur assimilation and defluorination, and generation of volatile fluorinated biotransformation products.

Key, B.D.; Criddle, C.S. [Michigan State Univ., East Lansing, MI (United States); Howell, R.D. [3M Environmental Technology and Safety Services, St. Paul, MN (United States)

1998-08-01

107

Advanced sulfur control concepts  

Microsoft Academic Search

Regenerable metal oxide sorbents, such as zinc titanate, are being developed to efficiently remove hydrogen sulfide (HS) from coal gas in advanced power systems. Dilute air regeneration of the sorbents produces a tailgas containing a few percent sulfur dioxide (SO). Catalytic reduction of the SO to elemental sulfur with a coal gas slipstream using the Direct Sulfur Recovery Process (DSRP)

S. K. Gangwal; B. S. Turk; R. P. Gupta

1995-01-01

108

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

NASA Astrophysics Data System (ADS)

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.

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

2010-12-01

109

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

SciTech Connect

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.

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

2008-07-02

110

Sulfuric acid on Europa and the radiolytic sulfur cycle.  

PubMed

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. PMID:10506568

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

1999-10-01

111

Adhesion Between Rubber Compounds Containing Various Adhesion Promoters and Brass-Plated Steel Cords. Part I. Effect of Sulfur Loading in Rubber Compounds  

Microsoft Academic Search

The adhesion property between rubber compounds containing different types of adhesion promoters (resinous adhesion promoter (containing both methylene donor and methylene acceptor), cobalt salt and zinc borate) and different loading amounts of sulfur and brass-plated steel cords was investigated to understand the effect of sulfur loading in the rubber compounds on their adhesion characteristics to the brass-plated steel cords. The

Gyung Soo Jeon

2008-01-01

112

Mortar damage due to airborne sulfur compounds in a simulation chamber  

Microsoft Academic Search

The interaction between airborne sulfur compounds and mortars has been investigated. Simulation experiments were carried out\\u000a in a flow chamber where temperature, relative humidity and SO2 concentration were controlled. Samples of lime, pozzolan and cement mortars were exposed for 90 days in air with 3 ppm of\\u000a SO2 concentration, at 25C temperature and 100% relative humidity. Following exposure, the mortar

G. Zappia; C. Sabbioni; M. G. Pauri; G. Gobbi

1994-01-01

113

Novel mesogenic polysiloxane solvents for gas-liquid chromatography. [Methylchrysene: isomers; sulfur heteronuclear compounds  

Microsoft Academic Search

The open-tubular column gas-chromatographic properties of a member of a new class of mesogenic polysiloxane (PMMS) phases are described and compared with those of a polymethylphenylsiloxane solvent (SE-52). The former is shown to yield high column efficiency commensurate with its gum-like character, yet concomitant high selectivity for positional isomers of methylchrysenes and for polycyclic aromatic and sulfur heteronuclear compounds. The

H. Finkelmann; R. J. Laub

1982-01-01

114

Modeling the overall persistence and environmental mobility of sulfur-containing polychlorinated organic compounds  

Microsoft Academic Search

Background, aim, and scopeExperimental data on partition coefficients and environmental half-lives of sulfur analogs of polychlorinated organic compounds\\u000a are scarce. Consequently, little is known about their overall persistence and long-range transport potential, which are the\\u000a most vital measures in the environmental exposure assessment. We performed Multimedia Modeling of environmental fate and transport\\u000a to complement this paucity of scientific data. The

Aleksandra Mostr?g; Tomasz Puzyn; Maciej Haranczyk

2010-01-01

115

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

Microsoft Academic Search

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 409.9mgkg?1 (dry weight), and dimethyl disulfide (DMDS), dimethyl sulfide (DMS), methyl 2-propenyl disulfide, carbonyl sulfide and methyl 1-propenyl sulfide were

Ting Wu; Xinming Wang; Dejun Li; Zhigang Yi

2010-01-01

116

The electrooxidation of sulfur-containing compounds at boron-doped diamond electrode  

Microsoft Academic Search

The electrooxidation of homocysteine, glutathione (GSH), 2-mercapto ethanesulfonic acid and cephalexin at boron-doped diamond (BDD) electrodes and glassy carbon (GC) electrodes was investigated by cyclic voltammetry. The oxidation of these sulfur-containing compounds exhibited well-defined irreversible responses. This preliminary study has shown that BDD has better sensitivity than GC. Concentration dependence has been studied and indicated the promise of using BDD

O. Chailapakul; P. Aksharanandana; T. Frelink; Y. Einaga; A. Fujishima

2001-01-01

117

Sulfur tolerant anode materials  

SciTech Connect

The goal of this program is the development of a molten carbonate fuel cell (MCFC) anode which is more tolerant of sulfur contaminants in the fuel than the current state-of-the-art nickel-based anode structures. This program addresses two different but related aspects of the sulfur contamination problem. The primary aspect is concerned with the development of a sulfur tolerant electrocatalyst for the fuel oxidation reaction. A secondary issue is the development of a sulfur tolerant water-gas-shift reaction catalyst and an investigation of potential steam reforming catalysts which also have some sulfur tolerant capabilities. These two aspects are being addressed as two separate tasks.

Not Available

1988-02-01

118

Biochemistry of sulfur  

SciTech Connect

This book presents information on the following topics: the chemistry of sulfur; the oxidation states of sulfur; the reduction of sulfate and the oxidation of sulfide; the sulfur cycle; oxidation of inorganic sulfide; the metabolism and functions of methionine; taurine and the oxidative metabolism of cysteine; thiols, disulfides, and thioesters; thioethers; thiamine; biotin; sulfates; inherited disorders of sulfur metabolism; cystinuria; sulfur and the metabolism of xenobiotics; general aspects of xenobiotic metabolism; glutathione and sulfation of xenobiotics; and metabolic activation as a result of sulfate conjugation.

Huxtable, R.J.; LaFranconi, W.M.

1986-01-01

119

Allocation of Sulfur to Sulfonium Compounds in Microalgae  

Microsoft Academic Search

Many algae are able to use S surplus to produce sulfonium compounds with different functions. Among these, dimethylsulfoniopropionate\\u000a (DMSP) has attracted the attention of the scientific community for its multiple functions. DMSP is produced by some salt-tolerant\\u000a angiosperms and by many marine algae. Different phytoplankton groups show different abilities to produce this compound: dinoflagellates,\\u000a diatoms, and coccolithophores usually produce large

Simona Ratti; Mario Giordano

120

Microbial removal of organic sulfur from coal (degradation of sulfur-containing heterocyclic compounds). Final report, July 1, 1984June 30, 1985  

Microsoft Academic Search

The presence of substantial levels of sulfur in coal is a major source of air pollution, and considerable efforts are being made to devise a cost-effective way of removing the sulfur. One promising method is the microbial desulfurization of coal. Recent research has shown that it is possible to remove almost all of the inorganic sulfur from coal using the

B. Klubek; D. Clark

1985-01-01

121

Microbial removal of organic sulfur from coal (bacterial degradation of sulfur-containing heterocyclic compounds): Final report, March 1, 1986February 28, 1987. [Thiobacillus  

Microsoft Academic Search

The presence of substantial levels of sulfur in coal is a major source of air pollution, and considerable efforts are being made to devise an inexpensive way of removing the sulfur. One promising method is microbial desulfurization. Almost all of the inorganic sulfur can be removed from coal by the bacteria Thiobacillus or Sulfolobus, which convert sulfide to sulfate but

B. Klubek; D. Clark

1987-01-01

122

Microbial removal of organic sulfur from coal (bacterial degradation of sulfur-containing heterocyclic compounds): Final report, July 1, 1985February 28, 1986  

Microsoft Academic Search

The presence of substantial levels of sulfur in coal is a major source of air pollution, and considerable afforts are being made to devise a cost-effective way of removing the sulfur. One promising method is the microbial desulfurization of coal. Recent research has shown that it is possible to remove almost all of the inorganic sulfur from coal using the

B. Klubek; D. Clark

1986-01-01

123

Regeneration of flue gas desulfurization waste liquors: Precipitation and hydrolysis of nitrogen-sulfur compounds  

SciTech Connect

Regeneration of the Fe[sup II] EDTA scrubbing liquors for simultaneous removal of SO[sub 2] and NO[sub x] in flue gas involves removing the nitrogen-sulfur (N-S) compounds accumulated in the liquor. In this paper, the authors investigate a simple regeneration process which selectively precipitates the N-S compounds as potassium salts and then hydrolyzes them to yield ammonium/potassium sulfate as a marketable byproduct. They believe this is the first report on precipitation and hydrolysis characteristics of N-S compounds in actual waste scrubbing liquor. Precipitation of the N-S compounds was achieved by adding K[sub 2]SO[sub 4] to the scrubbing liquor. The effects of the amount of added K[sub 2]SO[sub 4] on the amount of removed N-S compounds, precipitated crystals, and potassium left over in the scrubbing liquor were studied. Hydrolysis of the precipitated N-S compounds to ammonium sulfate was performed in a sulfuric acid environment. The effects of acidity, concentration of N-S compounds, and temperature of the hydrolysis are discussed. Analysis of the observed hydrolysis pattern showed that the reaction proceeded following first-order kinetics in terms of N-S compound concentration.

Kwon, T.M.; Randolph, A.D. (Univ. of Arizona, Tucson, AR (United States). Dept. of Chemical Engineering)

1994-04-01

124

The chemical processing of gas-phase carbonyl compounds by sulfuric acid aerosols: 2,4-pentanedione  

Microsoft Academic Search

This work investigates the interactions between gas-phase carbonyl compounds and sulfuric acid aerosols. It focuses on understanding the chemical processes, giving a first estimate of their importance in the atmosphere, and suggesting directions for further investigations. The solubility and reactivity of a compound with a large enolization constant, 2,4-pentanedione, in water\\/sulfuric acid solutions 096wt% have been investigated at room temperature

Barbara Nozire; Daniel D Riemer

2003-01-01

125

The Effects of Sulfur, Thiol, and Thiol Inhibitor Compounds on Arsine-Induced Toxicity in the Human Erythrocyte Membrane  

Microsoft Academic Search

The mechanism of arsine (AsH3) toxicity is not completely understood. The first cytotoxic effect of AsH3 is disruption of ion homeostasis, with a subsequent hemolytic action. The only ac- cepted treatment for AsH3 toxicity is exchange transfusion of the blood. In this study the effect of sulfur, sulfur compounds, thiol- containing compounds, and thiol inhibitors on AsH3-induced dis- ruption of

Leonard T. Rael; Felix Ayala-Fierro; Dean E. Carter

2000-01-01

126

[The problem and improvement of colorimetric method for determination of sulfite in foods containing sulfur compounds].  

PubMed

The modified Rankine colorimetric method for measuring sulfite added to food as a food additive has a low determination limit and is little influenced by interfering substances from foods. However, it can give erroneous results for foods containing Liliaceae Allium. So, four different methods, alkaline titration, a colorimetric method, ion chromatography and qualitative analysis with potassium iodate-starch paper, were examined. It was found that the sodium azide used in the colorimetric method forms sulfur dioxide during bubbling and heating. The proposed colorimetric method can be applied to food containing sulfur compounds, if sodium azide is omitted and 1% triethanolamine solution is used as an absorbent instead of 0.1 mol/L sodium hydroxide solution. PMID:15794092

Shimoi, Toshiko; Ibe, Akihiro; Tabata, Setsuko; Suzuki, Jin; Sadamasu, Yuki; Yasui, Akiko; Saito, Kazuo

2004-12-01

127

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

SciTech Connect

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.

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

128

Photoelectrochemical characterization of several semiconducting compounds of palladium with sulfur and/or phosphorus  

SciTech Connect

Semiconducting compounds of palladium with sulfur and/or phosphorus were prepared as crystals and their semiconducting and photoelectrochemical properties studied. The compounds include PdS, PdPS, Pd/sub 3/(PS/sub 4/)/sub 2/ and crystal growth was accomplished by chemical vapor transport with halogens and Bridgeman methods. Photoelectrochemical techniques were used to measure bandgap, transition type, doping level, majority carrier type, flatband potential, quantum yield for electron flow, and stability in a photoelectrochemical cell. The previously undetermined bandgap of PdP/sub 2/ is reported (1.08 eV, indirect).

Folmer, J.C.W.; Turner, J.A.; Parkinson, B.A.

1987-05-01

129

Sulfonates: A novel class of organic sulfur compounds in marine sediments  

SciTech Connect

X-ray absorption near-edge structure spectroscopy (XANES) used to measure sulfur speciation in a variety of organic-rich marine sediments has established sulfonates as a novel and major components of sedimentary organic sulfur. The origins of sulfonates in sediments are not clear, although both biological and geochemical mechanisms are possible. The accumulation of oxidized sulfonate sulfur in reducing marine sediments was not known previously; hence, a new perspective in sulfur geochemistry is established. The bigeochemical implications of the presence of sulfonates in marine sediments are discussed.

Vairavamurthy, A.; Zhou, W.; Manowitz, B. [Brookhaven National Lab., Upton, NY (United States); Eglinton, T. [Woods Hole Oceanographic Institution, MA (United States)

1994-11-01

130

Selective oxidations of organosulfur model compounds and coal for the removal of organic sulfur  

SciTech Connect

Investigations with organosulfur compounds have established that potassium monopersulfate (Oxone) in aqueous ethanol and sodium perborate in glacial acetic acid are highly selective oxidants for the oxidation of organic sum ides and aromatic sulfur heterocycles to their corresponding sulfoxides and sulfones. In a series of selective oxidations, dibenzothiophene in ethanol, fluorene in ethanol, and a 50:50 mol mixture of dibenzothiophene (DBT) and fluoresce in ethanol were reacted with aqueous Oxone under mild conditions. Capillary gas chromatographic analyses showed conversions of DBT to DBT-5,5-dioxide, while its carbon analog, fluorene was recovered quantitatively in every case. Furthermore, selective oxidations with Oxone of a triboelectrostatically cleaned Illinois {number sign}6 ultrafine coal (400 mesh {times} 0) and an Illinois {number sign}6 coal (IBC-101) (200 mesh {times} 0) depyritized via microorganisms were investigated. X-ray photoelectron spectroscopic (XPS) data indicated oxidation of a large fraction of the organic sulfur on the coal surface. Approximately 55--85% of the total S 2p area could be attributed to oxidized organic sulfur in the form of sulfones.

Fauth, D.J.; Baltrus, J.P.; Nowak, M.A.; Olson, G.J.

1991-01-01

131

Apparatus for recovery of sulfur  

SciTech Connect

This patent describes an apparatus for the recovery of sulfur from an underground sulfur formation. It comprises means for the injection of hot water into contact with the underground sulfur formation; means to permit the water and elemental sulfur to remain in contact, so as to melt at least a portion of the sulfur and form a mixture of molten sulfur and water; means for removing the mixture of molten sulfur and heated water to the surface; means for separating the water and sulfur mixture to recover molten sulfur and water; and means to recycle the water to the underground formation.

Peters, J.R.; Ramey, M.E.; Seyffert, A.E.; Canon, J.L.; Robinson, M.W.; Abercrombie, W.T.

1989-09-26

132

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

PubMed Central

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 GCMS. 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.

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

2013-01-01

133

ADVANCED SULFUR CONTROL CONCEPTS  

Microsoft Academic Search

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 (sulfur dioxide) tail gas. Under previous contracts the

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

2003-01-01

134

Sulfur 1s near edge x-ray absorption fine structure spectroscopy of thiophenic and aromatic thioether compounds.  

PubMed

Thiophenic compounds are major constituents of fossil fuels and pose problems for fuel refinement. The quantification and speciation of these compounds is of great interest in different areas such as biology, fossil fuels studies, geology, and archaeology. Sulfur 1s Near-Edge X-ray Absorption Fine Structure (NEXAFS) spectroscopy has emerged as a qualitative and quantitative method for sulfur speciation. A firm understanding of the sulfur 1s NEXAFS spectra of organosulfur species is required for these analytical studies. To support this development, the sulfur 1s NEXAFS spectra of simple thiols and thioethers were previously examined, and are now extended to studies of thiophenic and aromatic thioether compounds, in the gas and condensed phases. High-resolution spectra have been further analyzed with the aid of Improved Virtual Orbital (IVO) and ?(self-consistent field) ab initio calculations. Experimental sulfur 1s NEXAFS spectra show fine features predicted by calculation, and the combination of experiment and calculation has been used to improve the assignment of spectroscopic features important for the speciation and quantification of sulfur compounds. Systematic differences between gas and condensed phases are also explored; these differences suggest a significant role for conformational effects in the NEXAFS spectra of condensed species. PMID:23758366

Behyan, Shirin; Hu, Yongfeng; Urquhart, Stephen G

2013-06-01

135

Physiology of Haloalkaliphilic Sulfur-oxidizing Bacteria  

Microsoft Academic Search

The inorganic sulfur oxidation by obligate haloalkaliphilic chemolithoautotrophs was only recently discovered and investigated. These autotrophic sulfur oxidizing bacteria (SOB), capable of oxidation of inorganic sulfur compounds at moderate to high salt concentration and at high pH, can be divided into three genera belonging to the γ subdivision of the Proteobacteria: Thioalkalimicrobium, Thioalkalivibrio and Thioalkalispira. Their taxonomy, metabolic diversity and

H. L. Banciu

2004-01-01

136

Colourless sulfur bacteria and their role in the sulfur cycle  

Microsoft Academic Search

SummaryThe bacteria belonging to the families of the Thiobacteriaceae, Beggiatoaceae and Achromatiaceae are commonly called the colourless\\u000a sulfur bacteria. While their ability to oxidize reduced inorganic sulfur compounds has clearly been established, it is still\\u000a not known whether all these organisms can derive metabolically useful energy from these oxidations.\\u000a \\u000a During the last decades research has mainly focussed on the genus

J. Gijs Kuenen

1975-01-01

137

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

Microsoft Academic Search

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),

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

2011-01-01

138

Investigation on a new liquid redox method for H 2S removal and sulfur recovery with heteropoly compound  

Microsoft Academic Search

An innovative approach to H2S removal and sulfur recovery involving the use of heteropoly compounds was investigated systematically in this study. The favorable redox potential of sodium phosphomolybdate (HPAS) makes it thermodynamically feasible for it to oxidate H2S to elemental sulfur and to be regenerated by air. The presence of Na2CO3 in HPAS system can improve the absorption rate of

Rui Wang

2003-01-01

139

Microbial removal of organic sulfur from coal (bacterial degradation of sulfur-containing heterocyclic compounds): Final report, January 1December 31, 1988  

Microsoft Academic Search

The presence of substantial levels of sulfur in coal is a major source of air pollution, and considerable efforts are being made to devise a cost-effective way of removing the sulfur. One method is to mutate a laboratory species, Escherichia coli, an organism which is genetically well-understood and whose pathways for the metabolism of sulfur-containing amino acids have been extensively

Klubek

1989-01-01

140

Genome-wide transcriptional profiling of the purple sulfur bacterium Allochromatium vinosum DSM 180T during growth on different reduced sulfur compounds.  

PubMed

The purple sulfur bacterium Allochromatium vinosum DSM 180(T) 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

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

2013-07-19

141

Involvement of a Branched-Chain Aminotransferase in Production of Volatile Sulfur Compounds in Yarrowia lipolytica  

PubMed Central

The enzymatic degradation of l-methionine and the subsequent formation of volatile sulfur compounds (VSCs) are essential for the development of the typical flavor in cheese. In the yeast Yarrowia lipolytica, the degradation of l-methionine was accompanied by the formation of the transamination product 4-methylthio-2-oxobutyric acid. A branched-chain aminotransferase gene (YlBCA1) of Y. lipolytica was amplified, and the l-methionine-degrading activity and the aminotransferase activity were measured in a genetically modified strain and compared to those of the parental strain. Our work shows that l-methionine degradation via transamination is involved in formation of VSCs in Y. lipolytica.

Cernat Bondar, Daniela; Beckerich, Jean-Marie; Bonnarme, Pascal

2005-01-01

142

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

SciTech Connect

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.

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

1985-01-01

143

Novel mesogenic polysiloxane solvents for gas-liquid chromatography. [Methylchrysene: isomers; sulfur heteronuclear compounds  

SciTech Connect

The open-tubular column gas-chromatographic properties of a member of a new class of mesogenic polysiloxane (PMMS) phases are described and compared with those of a polymethylphenylsiloxane solvent (SE-52). The former is shown to yield high column efficiency commensurate with its gum-like character, yet concomitant high selectivity for positional isomers of methylchrysenes and for polycyclic aromatic and sulfur heteronuclear compounds. The nematic/isotropic temperature range of the new phase, 70/sup 0/ to 300/sup 0/ C, exceeds by several factors those of previously-described liquid-crystal stationary solvents, as does its upper useful temperature limit of 300/sup 0/C.

Finkelmann, H.; Laub, R.J.

1982-08-01

144

Export of Sulfur and Nitrogen Compounds From the East Asia Region in Spring  

NASA Astrophysics Data System (ADS)

Measurements of gaseous and particulate compounds of sulfur and reactive nitrogen species as well as other chemical species were made over the western Pacific during the NASA/TRACE-P experiment conducted between February and April 2001. Emission ratios of SO2, NOx, CO, and CO2 over East Asian countries were compared with observed ratios of increases of these species to study the transport efficiency of anthropogenic sulfur and reactive nitrogen compounds. The result obtained in this study suggests that only 20-40% and 10% of SO2 emitted over the continent was exported out into the western Pacific in an altitude range of 0-2 and 4-7 km, respectively. Similarly, a transport efficiency of reactive nitrogen compounds was suggested to be 10-35% and 10-20% at 0-2 and 4-7 km ranges. Only 2-4% and 0.5-1% of NOx emitted in the East Asia region was suggested to be transported in the form of NOx in these altitude ranges.

Koike, M.; Kondo, Y.; Kita, K.; Takegawa, N.; Masui, Y.; Weber, R.; Lee, Y.; Ma, Y.; Thornton, D.; Bandy, A.; Sachse, G.; Avery, M.; Vay, S.; Streets, D.; Miyazaki, Y.; Ikeda, H.

2002-12-01

145

Inhibition of enzymatic browning of chlorogenic acid by sulfur-containing compounds.  

PubMed

The antibrowning activity of sodium hydrogen sulfite (NaHSO(3)) was compared to that of other sulfur-containing compounds. Inhibition of enzymatic browning was investigated using a model browning system consisting of mushroom tyrosinase and chlorogenic acid (5-CQA). Development of brown color (spectral analysis), oxygen consumption, and reaction product formation (RP-UHPLC-PDA-MS) were monitored in time. It was found that the compounds showing antibrowning activity either prevented browning by forming colorless addition products with o-quinones of 5-CQA (NaHSO(3), cysteine, and glutathione) or inhibiting the enzymatic activity of tyrosinase (NaHSO(3) and dithiothreitol). NaHSO(3) was different from the other sulfur-containing compounds investigated, because it showed a dual inhibitory effect on browning. Initial browning was prevented by trapping the o-quinones formed in colorless addition products (sulfochlorogenic acid), while at the same time, tyrosinase activity was inhibited in a time-dependent way, as shown by pre-incubation experiments of tyrosinase with NaHSO(3). Furthermore, it was demonstrated that sulfochlorogenic and cysteinylchlorogenic acids were not inhibitors of mushroom tyrosinase. PMID:22416853

Kuijpers, Tomas F M; Narvez-Cuenca, Carlos-Eduardo; Vincken, Jean-Paul; Verloop, Annewieke J W; van Berkel, Willem J H; Gruppen, Harry

2012-03-26

146

Advanced sulfur control concepts  

SciTech Connect

Regenerable metal oxide sorbents, such as zinc titanate, are being developed to efficiently remove hydrogen sulfide (H{sub 2}S) from coal gas in advanced power systems. Dilute air regeneration of the sorbents produces a tailgas containing a few percent sulfur dioxide (SO{sub 2}). Catalytic reduction of the SO{sub 2} to elemental sulfur with a coal gas slipstream using the Direct Sulfur Recovery Process (DSRP) is a leading first-generation technology. Currently the DSRP is undergoing field testing at gasifier sites. The objective of this study is to develop second-generation processes that produce elemental sulfur without coal gas or with limited use. Novel approaches that were evaluated to produce elemental sulfur from sulfided sorbents include (1) sulfur dioxide (SO{sub 2}) regeneration, (2) substoichiometric (partial) oxidation, (3) steam regeneration followed by H{sub 2}S oxidation, and (4) steam-air regeneration. Preliminary assessment of these approaches indicated that developing SO{sub 2} regeneration faced the fewest technical and economic problems among the four process options. Elemental sulfur is the only likely product of SO{sub 2} regeneration and the SO{sub 2} required for the regeneration can be obtained by burning a portion of the sulfur produced. Experimental efforts have thus been concentrated on SO{sub 2}-based regeneration processes. Results from laboratory investigations are presented and discussed.

Gangwal, S.K.; Turk, B.S.; Gupta, R.P.

1995-11-01

147

Reduce claus sulfur emission  

Microsoft Academic Search

Operating efficiency of the world's more than 400 sulfur recovery plants must be increased to reduce sulfur emission. Unusually strict controls are being proclaimed by many governmental bodies which require careful design of new plants and improved operation of all plants to minimize side reactions and develop maximum recoveries. The Claus Process must be augmented with more reactors or other

1972-01-01

148

Elusive pyrite sulfur  

Microsoft Academic Search

Methods to analyze coal and coal refuse for pyrite sulfur and ash quickly and accurately is presented. ASTM, x-ray diffracton methods, an innovative new method which combines thermogravimetric analysis with ferromagnetism, and direct measurement by reduction of the sulfur to hydrogen sulfide are discussed.

Heunisch

2009-01-01

149

Detection and classification of gaseous sulfur compounds by solid electrolyte cyclic voltammetry of cermet sensor array.  

PubMed

Electrochemical sensors composed of a ceramic-metallic (cermet) solid electrolyte are used for the detection of gaseous sulfur compounds SO(2), H(2)S, and CS(2) in a study involving 11 toxic industrial chemical (TIC) compounds. The study examines a sensor array containing four cermet sensors varying in electrode-electrolyte composition, designed to offer selectivity for multiple compounds. The sensors are driven by cyclic voltammetry to produce a current-voltage profile for each analyte. Raw voltammograms are processed by background subtraction of clean air, and the four sensor signals are concatenated to form one vector of points. The high-resolution signal is compressed by wavelet transformation and a probabilistic neural network is used for classification. In this study, training data from one sensor array was used to formulate models which were validated with data from a second sensor array. Of the 11 gases studied, 3 that contained sulfur produced the strongest responses and were successfully analyzed when the remaining compounds were treated as interferents. Analytes were measured from 10 to 200% of their threshold-limited value (TLV) according to the 8-h time weighted average (TWA) exposure limits defined by the National Institute of Occupational Safety and Health (NIOSH). True positive classification rates of 93.3, 96.7, and 76.7% for SO(2), H(2)S, and CS(2), respectively, were achieved for prediction of one sensor unit when a second sensor was used for modeling. True positive rates of 83.3, 90.0, and 90.0% for SO(2), H(2)S, and CS(2), respectively, were achieved for the second sensor unit when the first sensor unit was used for modeling. Most of the misclassifications were for low concentration levels (such 10-25% TLV) in which case the compound was classified as clean air. Between the two sensors, the false positive rates were 2.2% or lower for the three sulfur compounds, 0.9% or lower for the interferents (eight remaining analytes), and 5.8% or lower for clean air. The cermet sensor arrays used in this analysis are rugged, low cost, reusable, and show promise for multiple compound detection at parts-per-million (ppm) levels. PMID:17386588

Kramer, Kirsten E; Rose-Pehrsson, Susan L; Hammond, Mark H; Tillett, Duane; Streckert, Holger H

2006-11-12

150

Regional river sulfur runoff  

SciTech Connect

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.

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

1985-01-20

151

Preparation of cerium-loaded Y-zeolites for removal of organic sulfur compounds from hydrodesulfurizated gasoline and diesel oil.  

PubMed

Ce(IV)-loaded Y-zeolites (CeY) were prepared for selective removal of the trace amount of organic sulfur compounds from hydrodesulfurization (HDS)-treated diesel oil. The CeY samples can be obtained from NH4-Y-zeolite (NH4Y) using liquid-phase ion-exchange and solid-state ion-exchange methods. The ion-exchange reactions, structures, and selective adsorptions of organic sulfur compounds of the CeY samples were investigated using XRD, IR, XPS, TEM, and GC sulfur analyzer. The organic sulfur compound uptakes strongly depend on the amount and the valency of Ce in the zeolite structure. Ce(IV) shows much higher adsorptive ability than Ce(III). A CeY-S sample prepared by solid-state ion-exchange reaction of NH4Y and Ce(NO3)3 with Ce/NH4 mole ratio of 0.63 at 250 degrees C showed a maximum sulfur uptake from a model solution of HDS-treated gasoline containing thiophene [S = 5 ppm (ppm = mg/L)]. A desulfurization from a HDS-treated diesel oil containing organic sulfur compounds (S = 1.87 ppm) and H2S (S = 0.73 ppm) was investigated with a combination of the CeY-S and a CuO adsorbent for removal of H2S by a batch method. The sulfur content was reduced to below 0.01 ppm for the first time. This method provides a promising desulfurization process to prepare a clean fuel for fuel cells. PMID:16458914

Xue, Mei; Chitrakar, Ramesh; Sakane, Kohji; Hirotsu, Takahiro; Ooi, Kenta; Yoshimura, Yuji; Toba, Makoto; Feng, Qi

2006-02-03

152

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

NASA Astrophysics Data System (ADS)

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.

Garces Trujillo, Hector Fabian

153

Microbial Removal of Organic Sulfur from Coal (Degradation of Sulfur-Containing Heterocyclic Compounds). Final Report, July 1, 1984-June 30, 1985.  

National Technical Information Service (NTIS)

The presence of substantial levels of sulfur in coal is a major source of air pollution, and considerable efforts are being made to devise a cost-effective way of removing the sulfur. One promising method is the microbial desulfurization of coal. Recent r...

B. Klubek D. Clark

1985-01-01

154

Microbial removal of organic sulfur from coal (bacterial degradation of sulfur-containing heterocyclic compounds): Final report, March 1December 31, 1987  

Microsoft Academic Search

The presence of levels of sulfur in coal is a major source of air pollution and considerable efforts are being made to devise a cost-effective way of removing it. One promising method is microbial desulfurization. Almost all of the inorganic sulfur can be removed from coal by the bacteria Thiobacillus or Sulfolobus, which convert sulfide to sulfate but leave the

B. Klubek; D. Clark

1988-01-01

155

Microbial Removal of Organic Sulfur from Coal (Bacterial Degradation of Sulfur-Containing Heterocyclic Compounds): Final Report, March 1-December 31, 1987.  

National Technical Information Service (NTIS)

The presence of levels of sulfur in coal is a major source of air pollution and considerable efforts are being made to devise a cost-effective way of removing it. One promising method is microbial desulfurization. Almost all of the inorganic sulfur can be...

B. Klubek D. Clark

1988-01-01

156

Polarizable Empirical Force Field for Sulfur-Containing Compounds Based on the Classical Drude Oscillator Model  

PubMed Central

Condensed-phase computational studies of molecules using molecular mechanics approaches require the use of force fields to describe the energetics of the systems as a function of structure. The advantage of polarizable force fields over non-polarizable (or additive) models lies in their ability to vary their electronic distribution as a function of the environment. Towards development of a polarizable force field for biological molecules, parameters for a series of sulfur-containing molecules are presented. Parameter optimization was performed to reproduce quantum mechanical and experimental data for gas phase properties including geometries, conformational energies, vibrational spectra, and dipole moments as well as for condensed phase properties such as heats of vaporization, molecular volumes, and free energies of hydration. Compounds in the training set include methanethiol, ethanethiol, propanethiol, ethyl methyl sulfide, and dimethyl disulfide. The molecular volumes and heats of vaporization are in good accordance with experimental values, with the polarizable model performing better than the CHARMM22 non-polarizable force field. Improvements with the polarizable model were also obtained for molecular dipole moments and in the treatment of intermolecular interactions as a function of orientation, in part due to the presence of lone pairs and anisotropic atomic polarizability on the sulfur atoms. Significant advantage of the polarizable model was reflected in calculation of the dielectric constants, a property that CHARMM22 systematically underestimates. The ability of this polarizable model to accurately describe a range of gas and condensed phase properties paves the way for more accurate simulation studies of sulfur-containing molecules including cysteine and methionine residues in proteins.

Zhu, Xiao; MacKerell, Alexander D.

2010-01-01

157

Retention parameters of sulfur-containing and aromatic compounds of petroleum in liquid chromatography on silica gel  

Microsoft Academic Search

gcompounds and are proposing a method for the quantitative calculation of the retention parameters of aromatic and naphthenoaromatic hydrocarbons and derivatives of thiophene. Most of the sulfur compounds that we have investigated were obtained by known methods; some of the compounds, specifically thiophene, benzothiophene, thiophane, dibutyl sulfide, and diphenyl sulfide, were used in the form of finished reagents. The octylthiophene

I. R. Khairudinov; M. A. Kolbin

1985-01-01

158

Polysulfide Sealant Compositions. 2. Interactions between Elemental Sulfur and Organosulfur Compounds. (Reannouncement with New Availability Information).  

National Technical Information Service (NTIS)

Added sulfur in polysulfide aircraft sealants can become chemically bound to the polymer backbone. The chemical processes involved, and their effect on thermal performance of the resulting sealants, have been examined. Reactions of aliphatic thiols with s...

P. J. Hanhela R. J. Hook D. B. Paul

1994-01-01

159

Evaluation of Occupational Exposure to Sulfur Compounds in Paper Pulp Kraft Mills  

Microsoft Academic Search

A study was carried out to provide a comprehensive profile of sulfur gas concentrations to which workers are exposed during the manufacture of paper pulp by the kraft process. Methods currently availableincluding colorimetric tubes, direct-reading monitors, and gas chromatographic methodswere compared. Gas chromatography is the only technique able to reliably measure individual sulfur gases. However, the necessity of using a

NICOLE GOYER

1990-01-01

160

Evolution and Ecology of Microbes Dissimilating Sulfur Compounds: Insights from Siroheme Sulfite Reductases  

Microsoft Academic Search

Sulfur microorganisms have been thriving on Earth since the dawn of life and are still of central importance for the functioning\\u000a of modern ecosystems. Here, we summarize the current perception of the evolution of dissimilatory siroheme sulfite reductases\\u000a (DSRs), antique key enzymes in the energy metabolism of sulfur microbes. We further give recent examples of the diversity\\u000a and ecology of

Alexander Loy; Stephan Duller; Michael Wagner

161

Sulfur geochemistry of Jurassic high-sulfur coals from Egypt  

Microsoft Academic Search

Jurassic high-sulfur coals from the Maghara area in Egypt were analyzed for the abundance and isotopic composition of different forms of sulfur. Analyses indicated that the sulfur occurs in the form of organic, pyrite, and sulfate forms. Pyrite sulfur represents the major fraction, while sulfate sulfur is minor and could be formed during sample preparation for the analyses.The ?34S CDT

Hassan Baioumy

2010-01-01

162

Sulfur capture mechanisms.  

National Technical Information Service (NTIS)

The Morgantown Energy Technology Center is currently involved in developing high-temperature cleanup for the integrated gasification combined cycle process. Solid sorbents are being employed to remove sulfur-bearing gases. Therefore, it is important to kn...

R. V. Siriwardane J. A. Poston S. D. Woodruff

1992-01-01

163

Emission characteristics of nitrogen- and sulfur-containing odorous compounds during different sewage sludge chemical conditioning processes.  

PubMed

Chemical conditioners are often used to enhance sewage sludge dewaterability through altering sludge properties and flocs structure, both affect odorous compounds emissions not only during sludge conditioning but also in subsequent sludge disposal. This study was to investigate emission characteristics of ammonia (NH(3)), sulfur dioxide (SO(2)), hydrogen sulfide (H(2)S) and carbonyl sulfide (COS) generated from sewage sludge conditioned by three representative conditioners, i.e., organic polymers, iron salts and skeleton builders, F-S (Fenton's reagent and skeleton builders) composite conditioner. The results demonstrate that polyacrylamide (PAM) has an insignificant effect on emission characteristics of nitrogen- and sulfur-containing odorous compounds, because the properties, sulfur and nitrogen speciations are similar in PAM-conditioned sludge and raw sludge (RS). Significant increases of SO(2) and H(2)S emissions in the H(2)SO(4) conditioning process were observed due to the accelerated decomposition of sulfur-containing amino acids in acidic environment. Fenton peroxidation facilitates the formation of COS. CaO can reduce sulfur-containing gases emission via generation of calcium sulfate. However, under strong alkaline conditions, free ammonia or protonated amine in sludge can be easily converted to volatile ammonia, resulting in a significant release of NH(3). PMID:22902143

Liu, Huan; Luo, Guang-Qian; Hu, Hong-Yun; Zhang, Qiang; Yang, Jia-Kuan; Yao, Hong

2012-08-07

164

Sulfur capture mechanisms  

Microsoft Academic Search

The Morgantown Energy Technology Center is currently involved in developing high-temperature cleanup for the integrated gasification combined cycle process. Solid sorbents are being employed to remove sulfur-bearing gases. Therefore, it is important to know the reaction mechanisms and kinetics of the interactions of the sulfur-bearing gases with sorbent materials, and the changes in elemental composition during reactions in order to

R. V. Siriwardane; J. A. Poston; S. D. Woodruff

1992-01-01

165

Separation of sulfur isotopes  

DOEpatents

Sulfur isotopes are continuously separated and enriched using a closed loop reflux system wherein sulfur dioxide (SO.sub.2) is reacted with sodium hydroxide (NaOH) or the like to form sodium hydrogen sulfite (NaHSO.sub.3). Heavier sulfur isotopes are preferentially attracted to the NaHSO.sub.3, and subsequently reacted with sulfuric acid (H.sub.2 SO.sub.4) forming sodium hydrogen sulfate (NaHSO.sub.4) and SO.sub.2 gas which contains increased concentrations of the heavier sulfur isotopes. This heavy isotope enriched SO.sub.2 gas is subsequently separated and the NaHSO.sub.4 is reacted with NaOH to form sodium sulfate (Na.sub.2 SO.sub.4) which is subsequently decomposed in an electrodialysis unit to form the NaOH and H.sub.2 SO.sub.4 components which are used in the aforesaid reactions thereby effecting sulfur isotope separation and enrichment without objectionable loss of feed materials.

DeWitt, Robert (Centerville, OH); Jepson, Bernhart E. (Dayton, OH); Schwind, Roger A. (Centerville, OH)

1976-06-22

166

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

Microsoft Academic Search

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

Ovidiu Ivanciuc; Teodora Ivanciuc; Alexandru T. Balaban

1998-01-01

167

Formation and photochemistry of organic sulfur compound-chlorine atom complexes  

NASA Astrophysics Data System (ADS)

Photochemical reactions of organic sulfur compounds (CH3SCH3, C2H5SCH3 and C2H5SC2H5)-chlorine atom complexes have been studied using a combined pulse radiolysis-laser flash photolysis technique. Excitation of all complexes has resulted in photobleaching with a similar quantum yield (0.370.07), independent of solvent polarities and concentration of solutes. The results were compared with previous studies of the analogous dimethyl sulfoxide (DMSO)-Cl complexes. It is concluded that the significant change of photobleaching quantum yields of the excited DMSO-Cl complex observed in the DMSO-CCl4 mixed solvent is mainly due to the specific solvation effect of DMSO for cations.

Okubo, Yu; Kido, Yuta; Fujiyoshi, Ryoko; Sumiyoshi, Takashi

2009-12-01

168

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

PubMed

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

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

2002-02-01

169

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

PubMed

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

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

2013-07-01

170

Measurement and biological significance of the volatile sulfur compounds hydrogen sulfide, methanethiol and dimethyl sulfide in various biological matrices  

Microsoft Academic Search

This review deals with the measurement of the volatile sulfur compounds hydrogen sulfide, methanethiol and dimethyl sulfide in various biological matrices of rats and humans (blood, serum, tissues, urine, breath, feces and flatus). Hydrogen sulfide and methanethiol both contain the active thiol (SH) group and appear in the free gaseous form, in the acid-labile form and in the dithiothreitol-labile form.

Albert Tangerman

2009-01-01

171

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

Microsoft Academic Search

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

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

2012-01-01

172

INVOLVEMENT OF VOLATILE SULFUR COMPOUNDS IN IONIZING RADIATION-INDUCED OFF-ODOR OF FRESH ORANGE JUICE  

Technology Transfer Automated Retrieval System (TEKTRAN)

The influences of ionizing radiation on volatile sulfur compounds in fresh Valencia orange juice were analyzed using GC-pulsed flame photometric detection and sensory evaluation. Methyl sulfide (MS) and methanethiol (MT) were induced most followed by dimethyl disulfide and dimethyl trisulfide. Car...

173

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

National Technical Information Service (NTIS)

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...

E. J. Kohout D. J. Miller L. A. Nieves D. S. Rothman C. L. Saricks

1990-01-01

174

Saturate biomarkers and aromatic sulfur compounds in oils and condensates from different source rock lithologies of Kazakhstan, Japan and Russia  

Microsoft Academic Search

Representative petroleums from the seven basins of Kazakhstan, Russia and Japan were analyzed using gas chromatography with dual FID\\/FPD and GC\\/MS. The present study has shown that the deviation in relative concentrations of aromatic sulfur compounds in petroleums could be related to the type of source rock. All oil samples were classified into three groups on the basis of the

Alexander Chakhmakhchev; Noriyuki Suzuki

1995-01-01

175

Model of Leaf Photosynthesis and the Effects of Simple Gaseous Sulfur Compounds (H Sub 2 S and SO sub 2 ).  

National Technical Information Service (NTIS)

A theoretical development is presented of a leaf model and the effects of simple sulfur compounds (H sub 2 S and SO sub 2 ) on photosynthesis based upon biochemical mechanisms. The model is developed to interpret short-term fumigation experiments and to u...

J. R. Kercher

1978-01-01

176

Ionizing radiation and antioxidants affect volatile sulfur compounds, lipid oxidation, and color of ready-to-eat Turkey bologna.  

PubMed

Bologna was processed from ground turkey breast meats containing one of four antioxidant treatments (none, rosemary extract, sodium erythorbate, and sodium nitrite). After it was cooked, the bologna was sliced, sealed in gas impermeable bags, exposed to 0, 1.5, and 3.0 kGy gamma-radiation, and then stored at 5 degrees C for up to 8 weeks. Thiobarbuturic acid reactive substances (TBARS), color, and volatile sulfur compounds were measured every 2 weeks during storage. Irradiation had no consistent effect on TBARS values. The rosemary extract and sodium nitrite inhibited, while erythorbate increased, TBARS values, independent of radiation dose or storage time. Irradiation promoted redness and reduced yellowness of the control (no antioxidant) bologna at weeks 0 and 2. The use of nitrite and rosemary extract inhibited the changes in color due to irradiation. Several volatile sulfur compounds (hydrogen sulfide, methanethiol, methyl sulfide, and dimethyl disulfide), measured using a pulsed flame photometric detector, increased with radiation dose. However, none of the antioxidants had any substantial effect on volatile sulfur compounds induced by irradiation. Our results suggest that antioxidants did not consistently affect irradiation-induced volatile sulfur compounds of turkey bologna although they did significantly impact color and lipid oxidation. PMID:15161223

Fan, Xuetong; Sommers, Christopher H; Sokorai, Kimberly J B

2004-06-01

177

The effects of biodegradation and water washing on sulfur compound speciation in crude oils from the Bolivar Coastal Fields. Revision  

Microsoft Academic Search

A series of crude oils from a partially and heavily biodegraded reservoir were analyzed for sulfur compound speciation by x-ray absorption spectroscopy. The primary new information is in the ratio of thiophenes to sulfides in the individual classes of oils. The most reasonable explanation of the data is that they represent a maturity sequence. There is no strong evidence that

B. Manowitz; Y. Jeon

1991-01-01

178

Effects of biodegradation and water washing on sulfur compound speciation in crude oils from the Bolivar Coastal Fields. Revision.  

National Technical Information Service (NTIS)

A series of crude oils from a partially and heavily biodegraded reservoir were analyzed for sulfur compound speciation by x-ray absorption spectroscopy. The primary new information is in the ratio of thiophenes to sulfides in the individual classes of oil...

B. Manowitz Y. Jeon

1991-01-01

179

Effects of biodegradation and water washing on sulfur compound speciation in crude oils from the Bolivar Coastal Fields.  

National Technical Information Service (NTIS)

A series of crude oils from a partially and heavily biodegraded reservoir were analyzed for sulfur compound speciation by x-ray absorption spectroscopy. The most reasonable explanation of the data is that they represent a maturity sequence. There is no st...

B. Manowitz Y. Jeon

1991-01-01

180

The effects of biodegradation and water washing on sulfur compound speciation in crude oils from the Bolivar Coastal Fields  

Microsoft Academic Search

A series of crude oils from a partially and heavily biodegraded reservoir were analyzed for sulfur compound speciation by x-ray absorption spectroscopy. The primary new information is in the ratio of thiophenes to sulfides in the individual classes of oils. The most reasonable explanation of the data is that they represent a maturity sequence. There is no strong evidence that

B. Manowitz; Y. Jeon

1991-01-01

181

Variation of some fermentative sulfur compounds in Italian "millesime" classic sparkling wines during aging and storage on lees.  

PubMed

Fermentative sulfur compounds are recognized as strongly affecting wine aroma, mainly as off-flavors, but recently also as possible positive contributors to wine quality and typicity in still wines. Nevertheless, no evidence has been provided for the influence of these molecules on sparkling wine aroma, except for peculiar volatile thiols found in French Champagne. According to the traditional method, the second fermentation, occurring in sealed bottles, is the essence of the procedure. After this fermentation, sparkling wine is aged on yeast lees for a period ranging from a few months to several years so that yeast autolysis can take place. So far, no evidence is provided for the effect of yeast contact duration on the level of sulfur compounds. Following a HS-SPME/GC-MS method, 13 sulfur compounds, that is, ethylmercaptan, dimethyl sulfide, diethyl sulfide, dimethyl disulfide, diethyl disulfide, methyl thioacetate, ethyl thioacetate, 2-mercaptoethanol, 2-(methylthio)-1-ethanol, 3-(methylthio)-1-propanol, 4-(methylthio)-1-butanol, benzothiazole, and 5-(2-hydroxyethyl)-4-methylthiazole, were quantified in several Italian sparkling wines, produced according to the traditional method in two wineries from Trentino-South Tyrol, region. Additionally, the influence of winemaking technology differences and vintage effects on the evolution of the quoted sulfur compounds was considered. This investigation was carried out by coupling the HS-SPME data with those obtained by SPE method and relevant to other volatile compounds, which are considered as winemaking markers. This work furnished the first evidence of the effect of aging and lees contact at different storage temperatures on the levels of these analytes in sparkling wines. Significant increments were observed for dimethyl sulfide, diethyl sulfide, 2-(methylthio)-1-ethanol, 3-(methylthio)-1-propanol, and 4-(methylthio)-1-butanol during aging with a different variation slope possibly due to the remarkably different storage temperatures. No clear influence of lees contact duration was found for the majority of the sulfur compounds considered. PMID:20806972

Fedrizzi, Bruno; Magno, Franco; Finato, Fabio; Versini, Giuseppe

2010-09-01

182

Method of removing pyritic sulfur from coal  

Microsoft Academic Search

The method is described of removing sulfur from coal, comprising: (a) subjecting subdivided pyritic sulfur-containing coal to heat decomposition with evolution of gas containing sulfur compounds; (b) progressively increasing the temperature of the decomposition from a temperature range below 375°C to a temperature range above 550°C; (c) separately collecting gas evolved within the temperature range from 375° to 550°C which

T. M. Godbold; W. R. Baker

1987-01-01

183

Sodium sulfur battery seal  

DOEpatents

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.

Mikkor, Mati (Ann Arbor, MI)

1981-01-01

184

Retention of Aromatic Sulfur-Containing Compounds on RP-HPLC: Correlation with Partition Coefficients and Molecular Connectivity Indices  

Microsoft Academic Search

The partition coefficients (log Kow) in n-octanol\\/water, together with the HPLC capacity factors (k?) measured on a C18 column, using methanol-water mobile phase of different compositions, were determined for 27 aromatic sulfur-containing compounds. The linear relationship between the log k? values and the percentage of the methanol in the eluent was tested for each compound. The best percentage of methanol

Hui Hong; Dai Zhou; Shuokui Han; Liansheng Wang; Zheng Zhang; Gongwei Zou

1996-01-01

185

Refinement of low-grade clay by microbial removal of sulfur and iron compounds using Thiobacillus ferrooxidans  

Microsoft Academic Search

The refinement of low-grade clay, of which impurities are mainly sulfur and iron compounds, is required because of the recent shortage of high-grade clay for manufacturing of structural ceramics. The major impurity compound contained in the low-grade clay we treated was identified as pyrite by X-ray powder diffraction and inductively coupled plasma analyses. The well-formed crystals of pyrite had a

Hee Wook Ryu; Kyeoung Suk Cho; Yong Keun Chang; Sang Done Kim; Tadahiro Mori

1995-01-01

186

Determination of Relative Concentrations of Primary and Secondary Organics and Speciation of Sulfur Compounds by Thermal Analysis and Photoelectron Spectroscopy.  

National Technical Information Service (NTIS)

Carbon-, sulfur-, and nitrogen-containing particles account for most of the anthropogenic aerosol particle burden. Methodology developed to quantitate the amounts of primary and secondary particulate carbon data are presented on speciation of sulfur compo...

T. Novakov R. L. Dod L. A. Gundel A. D. A. Hansen

1981-01-01

187

Comparison of breath and in-mouth collection for the measurement of oral malodorous compounds by gas chromatography using sulfur chemiluminescence detection  

Microsoft Academic Search

Volatile sulfur compounds (VSCs), specifically hydrogen sulfide, methyl mercaptan and dimethyl sulfide, are generally considered to be the primary volatiles responsible for 'morning' malodors in breath. To date, the 'gold standard' for detecting VSC concentrations in breath is the use of gas chromatography coupled with sulfur chemiluminescence detection. Breath gas is often collected in a polypropylene syringe and then aliquots

Debbie J. Paetznick; G. A. Reineccius; T. L. Peppard; J. M. Herkert; P. Lenton

2010-01-01

188

Comparison of breath and in-mouth collection for the measurement of oral malodorous compounds by gas chromatography using sulfur chemiluminescence detection  

Microsoft Academic Search

Volatile sulfur compounds (VSCs), specifically hydrogen sulfide, methyl mercaptan and dimethyl sulfide, are generally considered to be the primary volatiles responsible for morning malodors in breath. To date, the gold standard for detecting VSC concentrations in breath is the use of gas chromatography coupled with sulfur chemiluminescence detection. Breath gas is often collected in a polypropylene syringe and then aliquots

Debbie J Paetznick; G A Reineccius; T L Peppard; J M Herkert; P Lenton

2010-01-01

189

Chicken manure increased concentration of organic sulfur compounds in field-grown onions.  

PubMed

A field study was conducted at Kentucky State University (KSU) Research Farm. The soil in five plots was mixed with sewage sludge, five plots were mixed with yard waste compost, five plots were mixed with laying hen manure each at 15 t acre(-1), and five unamended plots that never received soil amendments were used for comparison purposes. Plots were planted with onion, Allium cepa L. var. Super Star-F1. The objectives of this investigation were to: 1) determine the concentrations of two organosulfur compounds (dipropyl disulfide and dipropyl trisulfide) in onion bulbs and 2) investigate the effect of mixing soil with three amendments (sewage sludge, yard waste, and chicken manure) on the concentration of dipropyl disulfide and dipropyl trisulfide in onion bulbs. Gas chromatographic/mass spectrometric (GC/MS) analyses of onion oil in chloroform extracts revealed the presence of two major fragment ions that correspond to dipropyl disulfide and - trisulfide. Concentration of these two organic sulfur compounds was greatest (1.5 and 0.8 mg 100 g(-1) fresh weight, respectively) in onion bulbs of plants grown in chicken manure and lowest (0.4 and 0.07 mg 100 g(-1) fresh weight, respectively) in onion bulbs of plants grown in yard waste compost treatments. We concluded that chicken manure could be exploited in growing onions with health-promoting properties. PMID:20183053

Antonious, George F; Perkins, Elizabeth; Cantor, Austin H

2009-06-01

190

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

PubMed

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

Vasyliv, O M; Hnatush, S O

191

The south Karelia air pollution study: Effects of low-level expsoure to malodorous sulfur compounds on symptoms  

SciTech Connect

Exposure to very low levels of ambient-air malodorous sulfur compounds and their effect on eye irritation, respiratory-tract symptoms, and central nervous system symptoms in adults were assessed. A cross-sectional self-administered questionnaire (response rate = 77%) was distributed during March and April 1992 to adults (n = 336) who lived in a neighborhood that contained a pulp mill and in a nonpolluted reference community (n = 380). In the exposed community, the measured annual mean concentrations of total reduced sulfur compounds and sulfur dioxide measured in two stations were 2 to 3 {mu}g/m{sup 3} and 1 {mu}g/m{sup 3}, respectively. In the reference community, the annual mean concentration of sulfur dioxide was 1 {mu}g/m{sup 3}. The residents of the community near the pulp mill reported an excess of cough, respiratory infections, and headache during the previous 4 wk, as well as during the preceding 12 mo. The relative risk for headache was increased significantly in the exposed community, compared with the reference area: the adjusted odds ratio (aOR) was 1.83 (95% confidence interval [95% Cl] = 1.06-3.15) during the previous 4 wk and 1.70 (95% Cl = 1.05-2.73) during the preceding 12 mo. The relative risk for cough was also increased during the preceding 12 mo (aOR = 1.64, 95% Cl = 1.01-2.64). These results indicated that adverse health effects of malodorous sulfur compounds occur at lower concentrations than reported previously. 25 refs., 3 tabs.

Partti-Pellinen, K.; Marttila, O. [South Karelia Allergy and Environment Inst., Tiuruniemi (Finland); Vilkka, V. [South Karelia Central Hospital, Lappeenranta (Finland); Jaakkola, J.J. [Univ. of Helsinki (Finland)]|[National Inst. of Public Health, Oslo (Norway)] [and others

1996-07-01

192

Hydrate sulfuric acid after sulfur implantation in water ice  

Microsoft Academic Search

For many years an ongoing research program performed at our laboratory has had the aim to investigate the implantation of reactive ions in ices relevant to planetology by using IR spectroscopy. We present new results obtained by implanting 200 keV sulfur ions into water ice at 80 K. We have looked at the formation of sulfur-bearing molecules such as sulfuric

G. Strazzulla; G. A. Baratta; G. Leto; O. Gomis

2007-01-01

193

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

NASA Astrophysics Data System (ADS)

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.

Murphy, Sean

194

The relationship between oral malodor and volatile sulfur compounds producing bacteria  

Microsoft Academic Search

Objectives: Halitosis can be a crippling social problem where the standard dental treatments and mouthwashes often recommended provide only temporary relief. Oral malodor is primarily the result of microbial metabolism. The mouth is home to hundreds of bacterial species with various nutritional preferences. These organisms enjoy proteins, as they digest proteins several fetid substances arise. The role of volatile sulfur

Yosef P. Krespi; Mel Rosenberg

2004-01-01

195

Regional air pollution study: sulfur compounds and particulate size distribution inventory. Final report  

Microsoft Academic Search

In conjunction with the Regional Air Pollution Study being conducted in the St. Louis Air Quality Control Region (AQCR), a methodology for estimating the amount of sulfur trioxide (SO) emitted by combustion sources was developed. It is based on SO\\/SO ratios determined both experimentally and from literature surveys. The most likely value appears to be 1.85% of the SO emissions.

F. E. Littman; R. W. Griscom; H. Wang

1977-01-01

196

REGIONAL AIR POLLUTION STUDY: SULFUR COMPOUNDS AND PARTICULATE SIZE DISTRIBUTION INVENTORY  

EPA Science Inventory

In conjunction with the Regional Air Pollution Study being conducted in the St. Louis Air Quality Control Region (AQCR), a methodology for estimating the amount of sulfur trioxide (SO3) emitted by combustion sources was developed. It is based on SO2/SO3 ratios determined both exp...

197

Instrumental methods of analysis of sulfur compounds in synfuel process streams. Quarterly technical progress report, October-December 1982  

Microsoft Academic Search

The general objective is to develop dependable and accurate instrumental analysis methods for the determination of sulfur moieties. These will include polysulfides, dithionite and polythionates. Calorimetric procedures (thermometric titrations, injection enthalpimetry) and electroanalytical techniques (voltammetry, coulometric analysis, etc.) will be used. The complete speciation of sulfur will be undertaken in representative synfuel process stream samples. Total sulfidic sulfur has been

J. Jordan; J. Stahl; J. Yakupkovic

1983-01-01

198

Process for removing sulfur from coal  

DOEpatents

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.

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

1983-08-11

199

Development of Specialized Sulfur Concretes.  

National Technical Information Service (NTIS)

Specialized sulfur concretes were developed by the Federal Bureau of Mines as a result of research for the beneficial utilization of sulfur in construction materials. Materials were developed for use in acid and salt corrosive environments where portland ...

T. A. Sullivan W. C. McBee

1979-01-01

200

Concentration and removal of nitrogen and sulfur containing compounds from organic liquids phases using electrochemically reversed chemical complexation  

SciTech Connect

A process is being developed to concentrate and remove sulfur- and nitrogen-containing compounds from organic liquid phases. These phases could include coal liquids, oil from shale or tar sands, as well as conventional crude oil. This process uses reversible complexation and electrolysis. A cyclical contacting scheme is proposed: the compounds are first extracted from a polluted hydrocarbon phase using an aqueous phase containing a complexing agent; the aqueous phase is then contacted with a waste hydrocarbon phase and the complexing agent is oxidized, releasing any complexed pollutants into the waste hydrocarbon phase. This cycle is repeated to extract more pollutants, i.e. sulfur and nitrogen compounds, from the contaminated phase and concentrate them in the waste phase. A description of the process and preliminary results for one system are presented.

Koval, C.A.; Drew, S.M.; Spontarelli, T.; Noble, R.D.

1988-10-01

201

Removal of Sulfur from Hydrotreated Diesel Fuel  

Microsoft Academic Search

A simple and ecological two-stage method of removing sulfur from hydrotreated diesel fuel is described. In the first stage, the sulfur compounds left in the fuel are oxidized by hydrogen peroxide into sulfones, and in the second stage, the sulfones formed are extracted from the oxidation product by adsorption with silica gel. The diesel fuel obtained with this method satisfies

A. Kh. Sharipov; V. R. Nigmatullin

2005-01-01

202

Adventures in Organic Sulfur Chemistry  

Microsoft Academic Search

On several occasions, SULFUR REPORTS has invited persons who have done outstanding work in sulfur chemistry to summarize highlights of their research career in a semiautobiographical review. The present account is from a distinguished chemist who has contributed importantly for nearly 50 years to medicinal and organic aspects of sulfur chemistry. Ernest E. Campaigne (who prefers simply E. Campaigne) was

E. Campaigne

1990-01-01

203

Method of capturing sulfur  

Microsoft Academic Search

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

R. D. Stewart; R. L. Gamble

1984-01-01

204

Advanced Sulfur Control Processing  

Microsoft Academic Search

The primary objective of this project is to determine the feasibility of an alternate concept for the regeneration of high temperature desulfurization sorbents in which elemental sulfur, instead of SO, is produced. If successful, this concept will eliminate or alleviate problems caused by the highly exothermic nature of the regeneration reaction, the tendency for metal sulfate formation, and the need

S. K. Gangwal; J. W. Portzer; B. S. Turk; R. Gupta

1996-01-01

205

For sale: Sulfur emissions  

Microsoft Academic Search

The allowance trading market has started a slow march to maturity. Competitive developers should understand the risks and opportunities now presented. The marketplace for sulfur dioxide (SO) emissions allowances - the centerpiece of Title 4's acid rain reduction program - remains enigmatic 19 months after the Clean Air Act amendments of 1990 were passed. Yet it is increasingly clear that

Heiderscheit

2009-01-01

206

Processing high sulfur coal  

SciTech Connect

Coal is fed to a liquefaction process, and a resulting slurry of ash, unconverted coal, and liquids is fed to a delayed coker. Distillates are hydrotreated and stored or recycled, and the coke is calcined at high temperature to reduce the sulfur content.

Sooter, M.C.

1981-09-29

207

Sodium sulfur battery seal  

DOEpatents

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.

Topouzian, Armenag (Birmingham, MI)

1980-01-01

208

CONTROLLING SULFUR OXIDES  

EPA Science Inventory

This Research Summary describes EPA's program to develop new and improve existing technologies for sulfur oxides control. As we increasingly turn to coal as the primary utility and industrial fuel, while trying to deal with the problems of acid precipitation, visibility degradati...

209

Measurement and biological significance of the volatile sulfur compounds hydrogen sulfide, methanethiol and dimethyl sulfide in various biological matrices.  

PubMed

This review deals with the measurement of the volatile sulfur compounds hydrogen sulfide, methanethiol and dimethyl sulfide in various biological matrices of rats and humans (blood, serum, tissues, urine, breath, feces and flatus). Hydrogen sulfide and methanethiol both contain the active thiol (-SH) group and appear in the free gaseous form, in the acid-labile form and in the dithiothreitol-labile form. Dimethyl sulfide is a neutral molecule and exists only in the free form. The foul odor of these sulfur volatiles is a striking characteristic and plays a major role in bad breath, feces and flatus. Because sulfur is a biologically active element, the biological significance of the sulfur volatiles are also highlighted. Despite its highly toxic properties, hydrogen sulfide has been lately recommended to become the third gasotransmitter, next to nitric oxide and carbon monoxide, based on high concentration found in healthy tissues, such as blood and brain. However, there is much doubt about the reliability of the assay methods used. Many artifacts in the sulfide assays exist. The methods to detect the various forms of hydrogen sulfide are critically reviewed and compared with findings of our group. Recent findings that free gaseous hydrogen sulfide is absent in whole blood urged the need to revisit its role as a blood-borne signaling molecule. PMID:19505855

Tangerman, Albert

2009-05-21

210

Emission of volatile organic sulfur compounds from a heavily polluted river in Guangzhou, South China.  

PubMed

Emissions of five volatile organic sulfur compounds (VOSCs), including methanethiol, carbonyl sulfide, dimethyl sulfide, carbon disulfide, and dimethyl disulfide, from a heavily polluted river, Shijing River in Guangzhou of South China, was studied. The results showed that the amounts of all VOSCs emitted from the river increased from downstream to upstream along the river with increasing magnitude of water pollution. The emission of carbonyl sulfide was the highest among the target analytes, ranging from 23.8 microg m(-2) h(-1) to 42.6 microg m(-2) h(-1) at the water surface of Shijin River. The concentration levels of VOSCs on the riverbank were lower than those at the water surface either in Shijing River or in Liuxi River. However, the contribution of dimethyl disulfide to the total VOSCs on the riverbank was higher than that at the water surface in most sampling sites, indicating that there might be a point source of dimethyl disulfide on the riverbank besides diffusion from water surface. The 24-h semi-continuous monitoring data revealed that the emissions of VOSCs at the water surface peaked at 9:00 and 21:00, which was consistent with the water quality variability in Shijin River caused by daily tidal variation. PMID:17849226

Sheng, Yanqing; Chen, Fanzhong; Yu, Ying; Wang, Xinming; Sheng, Guoying; Fu, Jiamo; Zeng, Eddy Y

2007-09-12

211

Computational Studies of CO2 Activation via Photochemical Reactions with Reduced Sulfur Compounds  

PubMed Central

Reactions between CO2 and reduced sulfur compounds (RSC) - H2S and CH3SH - were investigated using ground and excited state density functional theory (DFT) and coupled cluster (CC) methods to explore possible RSC oxidation mechanisms and CO2 activation mechanisms in the atmospheric environment. Ground electronic state calculations at the CR-CC(2,3)/6-311+G(2df,2p)//CAM-B3LYP/6-311+G(2df,2p) level show proton transfer as a limiting step in the reduction of CO2 with activation energies of 49.64 and 47.70 kcal/mol, respectively, for H2S and CH3SH. On the first excited state surface, CR-EOMCC(2,3)/6-311+G(2df,2p)//CAM-B3LYP/6-311+G(2df,2p) calculations reveal that energies of <250 nm are needed to form H2S-CO2 and CH3SH-CO2 complexes allowing facile hydrogen atom transfer. Once excited, all reaction intermediates and transition states are downhill energetically showing either C-H or C-S bond formation in the excited state whereas only C-S bond formation was found in the ground state. Environmental implications of these data are discussed with a focus on tropospheric reactions between CO2 and RSC, as well as potential for carbon sequestration using photocatalysis.

Baltrusaitis, Jonas; Patterson, Eric; Hatch, Courtney

2012-01-01

212

Measurements of Volatile Organic Compounds and Gaseous Sulfuric Acid During the 2008 CAREBEIJING Campaign  

NASA Astrophysics Data System (ADS)

Air quality in Beijing has been a hot topic recently, because Beijing hosted the 2008 summer Olympics. To combat the problem, China ordered numerous factories shut down or used only sporadically during the games to limit air pollution in the area. Another major step involved ordering about one-half of the city's 3.3 million vehicles off the road during the games, allowing only cars on roads with odd or even-numbered license plates on alternate days until the games were over. In addition, China has implemented new auto emission standards since March 2009 with regulations that are similar to those used throughout Europe. Our team at the Texas A&M participated in the 2008 CAREBEIJING campaign, with the objectives of studying the complex chemistry of the air in Beijing, looking at emission controls and their effectiveness, studying the surrounding air from other regions and how it can affect Beijing's air, and comparing all of our findings with air quality in other cities we have examined, such as Mexico City and Houston. In this talk, preliminary results of measurements of volatile organic compounds (VOCs) and gaseous sulfuric acid will be presented to discuss the trends of VOCs and new particle formation associated with the traffic control.

Zhang, R.; Zheng, J.; Hu, M.; Zhu, T.

2009-05-01

213

Permanganate oxidation of sulfur compounds to prevent poisoning of Pd catalysts in water treatment processes.  

PubMed

The practical application of Pd-catalyzed water treatment processes is impeded by catalyst poisoning by reduced sulfur compounds (RSCs). In this study, the potential of permanganate as a selective oxidant for the removal of microbially generated RSCs in water and as a regeneration agent for S-poisoned catalysts was evaluated. Hydrodechlorination using Pd/Al2O3 was carried out as a probe reaction in permanganate-pretreated water. The activity of the Pd catalysts in the successfully pretreated reaction medium was similar to that in deionized water. The catalyst showed no deactivation behavior in the presence of permanganate at a concentration level < or = 0.07 mM. With a residual oxidant concentration of > or = 0.08 mM, a significant but temporary inhibition of the catalytic dechlorination was observed. Unprotected Pd/Al2O3, which had been completely poisoned by sulfide, was reactivated by a combined treatment with permanganate and hydrazine. However, the anthropogenic water pollutants thiophene and carbon disulfide were resistant against permanganate. Together with the preoxidation of catalyst poisons, hydrophobic protection of the catalysts was studied. Pd/zeolite and various hydrophobically coated catalysts showed a higher stability against ionic poisons and permanganate than the uncoated catalyst. By means of a combination of oxidative water pretreatment and hydrophobic catalyst protection, we provide a new tool to harness the potential of Pd-catalyzed hydrodehalogenation for the treatment of real waters. PMID:18754501

Angeles-Wedler, Dalia; Mackenzie, Katrin; Kopinke, Frank-Dieter

2008-08-01

214

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

PubMed

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

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

2001-01-01

215

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

PubMed

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

Calil, Caroline Morini; Marcondes, Fernanda Klein

2006-03-29

216

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

SciTech Connect

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.

Farin, W.G.

1984-02-14

217

Combined chemical and microbiological removal of organic sulfur from coal  

SciTech Connect

The objective of this work is to investigate techniques for chemically converting the sulfur containing organic compounds in coal to compounds that can be treated microbiologically to remove the organically bound sulfur. The goal is to achieve an economically feasible mild chemical oxidation of the organic sulfur in a representative Illinois Basin coal by converting the sulfur to sulfoxides and sulfones; the carbon sulfur bond in the sulfoxides and sulfones would then be broken microbiologically and the sulfur removed from the coal as sulfate.

Raphaelian, L.A.

1991-01-01

218

Latitudinal Variations of Sulfur Compounds in the Venus Atmosphere Based on the Correlation Between VLA Observations and Radio Occultation Results  

Microsoft Academic Search

To identify the presence of potential spatial variations in the distributions of sulfur compounds (H_2SO_4(g) and SO_2) across the disk of Venus, a dual-frequency radio observation was performed with the NRAO\\/VLA at 14.94 GHz (2 cm) and 22.46 GHz (1.3 cm) on April 5, 1996. The resulting brightness maps have been compared with a radiative transfer model, which shows both

M. A. Kolodner; S. H. Suleiman; B. J. Butler; P. G. Steffes

1997-01-01

219

Simultaneous measurement of volatile sulfur compounds using ascorbic acid for oxidant removal and gas chromatographyflame photometric detection  

Microsoft Academic Search

A method for the simultaneous measurement of volatile sulfur compounds (COS, H2S, CS2, CH3SH, DMS) is established with preconcentration and GCflame 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.

Yayoi Inomata; Katsuji Matsunaga; Yasuhiro Murai; Kazuo Osada; Yasunobu Iwasaka

1999-01-01

220

Complete genome sequence of Desulfocapsa sulfexigens, a marine deltaproteobacterium specialized in disproportionating inorganic sulfur compounds  

PubMed Central

Desulfocapsa sulfexigens SB164P1 (DSM 10523) belongs to the deltaproteobacterial family Desulfobulbaceae and is one of two validly described members of its genus. This strain was selected for genome sequencing, because it is the first marine bacterium reported to thrive on the disproportionation of elemental sulfur, a process with a unresolved enzymatic pathway in which elemental sulfur serves both as electron donor and electron acceptor. Furthermore, in contrast to its phylogenetically closest relatives, which are dissimilatory sulfate-reducers, D. sulfexigens is unable to grow by sulfate reduction and appears metabolically specialized in growing by disproportionating elemental sulfur, sulfite or thiosulfate with CO2 as the sole carbon source. The genome of D. sulfexigens contains the set of genes that is required for nitrogen fixation. In an acetylene assay it could be shown that the strain reduces acetylene to ethylene, which is indicative for N-fixation. The circular chromosome of D. sulfexigens SB164P1 comprises 3,986,761 bp and harbors 3,551 protein-coding genes of which 78% have a predicted function based on auto-annotation. The chromosome furthermore encodes 46 tRNA genes and 3 rRNA operons.

Finster, Kai Waldemar; Kjeldsen, Kasper Urup; Kube, Michael; Reinhardt, Richard; Mussmann, Marc; Amann, Rudolf; Schreiber, Lars

2013-01-01

221

Complete genome sequence of Desulfocapsa sulfexigens, a marine deltaproteobacterium specialized in disproportionating inorganic sulfur compounds.  

PubMed

Desulfocapsa sulfexigens SB164P1 (DSM 10523) belongs to the deltaproteobacterial family Desulfobulbaceae and is one of two validly described members of its genus. This strain was selected for genome sequencing, because it is the first marine bacterium reported to thrive on the disproportionation of elemental sulfur, a process with a unresolved enzymatic pathway in which elemental sulfur serves both as electron donor and electron acceptor. Furthermore, in contrast to its phylogenetically closest relatives, which are dissimilatory sulfate-reducers, D. sulfexigens is unable to grow by sulfate reduction and appears metabolically specialized in growing by disproportionating elemental sulfur, sulfite or thiosulfate with CO2 as the sole carbon source. The genome of D. sulfexigens contains the set of genes that is required for nitrogen fixation. In an acetylene assay it could be shown that the strain reduces acetylene to ethylene, which is indicative for N-fixation. The circular chromosome of D. sulfexigens SB164P1 comprises 3,986,761 bp and harbors 3,551 protein-coding genes of which 78% have a predicted function based on auto-annotation. The chromosome furthermore encodes 46 tRNA genes and 3 rRNA operons. PMID:23961312

Finster, Kai Waldemar; Kjeldsen, Kasper Urup; Kube, Michael; Reinhardt, Richard; Mussmann, Marc; Amann, Rudolf; Schreiber, Lars

2013-04-15

222

Gas chromatographic and capillary gas chromatographic\\/mass spectrometric determination of organic sulfur compounds (OSCs) in sediment from ports: Significance of these compounds as an oil pollution index  

Microsoft Academic Search

Oil pollution arises in waters near petroleum industrial districts. In oily odor fish caught in the coast near petroleum industries, toluene, other aromatic hydrocarbons and olefinic hydrocarbons have been detected. The authors also reported the presence of organic sulfur compounds (OSCs), probably originating from polluting oil, in fish caught in the Seto Inland Sea after an accidental oil spilling from

Masana Ogata; Kuniyasu Fujisawa

1990-01-01

223

Sulfur-substituted tetrahedranes.  

PubMed

The stable sulfur-substituted tetrahedrane derivatives 2-4 were synthesized by the reaction of tris(trimethylsilyl)tetrahedranyllithium 1 with diphenyl disulfide, bis(4-nitrophenyl) disulfide, and bis(2,4-dinitrophenyl) disulfide, respectively, and characterized by both NMR spectroscopy and X-ray crystallography. Phenylsulfonyltetrahedrane 5 was prepared by the reaction of 2 and m-chloroperbenzoic acid. The UV-vis absorption spectra of 2-4 suggested an interaction of the ? orbital of the tetrahedrane core and the lone-pair electrons on the sulfur atom, whereas no interaction for 5 was found. Thermal reactions of 2 and 5 are also reported; 2 underwent fragmentation into two acetylene molecules, whereas 5 gave the corresponding cyclobutadiene. PMID:21728313

Ochiai, Tatsumi; Nakamoto, Masaaki; Inagaki, Yusuke; Sekiguchi, Akira

2011-07-07

224

Genomic Insights into the Sulfur Metabolism of Phototrophic Green Sulfur Bacteria  

Microsoft Academic Search

Green sulfur bacteria (GSB) utilize various combinations of sulfide, elemental sulfur, thiosulfate, ferrous iron, and hydrogen\\u000a for anaerobic photoautotrophic growth. Genome sequence data is currently available for 12 strains of GSB. We present here\\u000a a genome-based survey of the distribution and phylogenies of genes involved in oxidation of sulfur compounds in these strains.\\u000a Sulfide:quinone reductase, encoded by sqr, is the

Niels-Ulrik Frigaard; Donald A. Bryant

225

Genomic and Evolutionary Perspectives on Sulfur Metabolism in Green Sulfur Bacteria  

Microsoft Academic Search

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

Niels-Ulrik Frigaard; Donald A. Bryant

226

New sulfur-containing corrosion inhibitor  

SciTech Connect

No corrosion inhibitor available today is ideal in every way, but a new class of sulfur-containing compounds promises to address many field requirements. This article describes the performance characteristics of these compounds and discusses possible inhibition mechanisms. The emphasis in this work was on better understanding corrosion inhibition by sulfur-containing inhibitors under high shear-stress conditions, with special focus on localized (pitting) corrosion. The results indicate that the new sulfur-containing inhibitors (e.g., mercaptoalcohol [MA]) could be more effective in the field than currently available inhibitors.

Prince, P.

2000-04-01

227

Assimilatory Sulfur Metabolism in Marine Microorganisms.  

National Technical Information Service (NTIS)

The transport of sulfate and its reductive assimilation into cellular organic sulfur compounds and protein was studied in aerobic marine bacteria. Pure culture of Pseudomonas halodurans and Alteromonas luteoviolaceus were used for characterization of sulf...

R. L. Cuhel

1981-01-01

228

Beyond the sulfur effect  

SciTech Connect

The addition of reactive elements (REs) is known to increase the adherence of Al{sub 2}O{sub 3} scales and the underlying alloys. A widely accepted mechanism is that the REs getter the sulfur impurity in the alloy, thus preventing it from segregating to the scale-alloy interface to weaken the interfacial bonding. This paper provides evidence showing that not all S-free interfaces are strong. Although eliminating the sulfur in the alloy can greatly improve scale adhesion, the presence of RE clearly has additional beneficial effects that make the scale-alloy interface even stronger. Fe{sub 3}Al-base alloys, with or without Zr additions or a desulfurization H{sub 2}-anneal were oxidized at 1000 C in O{sub 2}. The amount of sulfur at the Al{sub 2}O{sub 3}-alloy interface was studied after the scales were removed by scratching with a diamond stylus in ultra-high vacuum using Auger spectroscopy. The interface composition was related to the spallation resistance of the scale.

Hou, P.Y. [Lawrence Berkeley National Lab., CA (United States). Materials Science Div.

1999-10-01

229

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

PubMed

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

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

230

Transfer of sulfur: from simple to diverse.  

PubMed

The introduction of sulfur atoms onto target molecules is an important area in organic synthesis, in particular in the synthesis of pharmaceutical compounds, and a wide variety of sulfuration agents have been developed for thionation reactions over the past few decades. In this Focus Review, we collect and summarize the C?S bond-formation reactions that have been used to construct C?S bonds in natural products and pharmaceutical compounds. PMID:23846983

Liu, Hui; Jiang, Xuefeng

2013-07-11

231

The chemical processing of gas-phase carbonyl compounds by sulfuric acid aerosols: 2,4-pentanedione  

NASA Astrophysics Data System (ADS)

This work investigates the interactions between gas-phase carbonyl compounds and sulfuric acid aerosols. It focuses on understanding the chemical processes, giving a first estimate of their importance in the atmosphere, and suggesting directions for further investigations. The solubility and reactivity of a compound with a large enolization constant, 2,4-pentanedione, in water/sulfuric acid solutions 0-96 wt% have been investigated at room temperature using the bubble column/GC-FID technique. 2,4-pentanedione was found to undergo aldol condensation at acidities as low as 20 wt% H 2SO 4, that is, well in the tropospheric range of aerosol composition. In agreement with well-established organic chemical knowledge, this reaction resulted in changes of color of the solutions of potential importance for the optical properties of the aerosols. 2,4-pentanedione was also found to undergo retroaldol reaction, specific to dicarbonyl compounds, producing acetone and acetaldehyde. The Henry's law coefficient for 2,4-pentanedione was found to be a factor 5 larger than the one of acetone over the whole range of acidity, with a value in water of H (297 K)=(15527) M atm -1. A chemical system is proposed to describe the transformations of carbonyl compounds in sulfuric acid aerosols. Aldol condensation is likely to be the most common reaction for these compounds, probably involving a large number of the ones present in the atmosphere and a wide range of aerosol compositions. The enolization constant contributes as a proportional factor to the rate constant for aldol condensation, and is shown in this work to contribute as an additive constant to the Henry's law coefficient. In addition to the many important aspects of these reactions illustrated in this work, the rate of aldol condensation was estimated to be potentially fast enough for the losses of some compounds in acidic aerosols to compete with their gas-phase chemistry in the atmosphere.

Nozire, Barbara; Riemer, Daniel D.

232

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

Microsoft Academic Search

The selectivity of Rhodococcus sp. strain JVH1 among selected sulfidic and thiophenic compounds was investigated in both single-liquid-phase (aqueous) cultures\\u000a and in two-liquid-phase cultures, where the sulfur compounds were dissolved in 2,2,4,4,6,8,8-heptamethylnonane as the immiscible\\u000a 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

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

2007-01-01

233

Expression and functional roles of Bradyrhizobium japonicum genes involved in the utilization of inorganic and organic sulfur compounds in free-living and symbiotic conditions.  

PubMed

Strains of Bradyrhizobium spp. form nitrogen-fixing symbioses with many legumes, including soybean. Although inorganic sulfur is preferred by bacteria in laboratory conditions, sulfur in agricultural soil is mainly present as sulfonates and sulfur esters. Here, we show that Bradyrhizobium japonicum and B. elkanii strains were able to utilize sulfate, cysteine, sulfonates, and sulfur-ester compounds as sole sulfur sources for growth. Expression and functional analysis revealed that two sets of gene clusters (bll6449 to bll6455 or bll7007 to bll7011) are important for utilization of sulfonates sulfur source. The bll6451 or bll7010 genes are also expressed in the symbiotic nodules. However, B. japonicum mutants defective in either of the sulfonate utilization operons were not affected for symbiosis with soybean, indicating the functional redundancy or availability of other sulfur sources in planta. In accordance, B. japonicum bacteroids possessed significant sulfatase activity. These results indicate that strains of Bradyrhizobium spp. likely use organosulfur compounds for growth and survival in soils, as well as for legume nodulation and nitrogen fixation. PMID:21190435

Sugawara, Masayuki; Shah, Gopit R; Sadowsky, Michael J; Paliy, Oleg; Speck, Justin; Vail, Andrew W; Gyaneshwar, Prasad

2011-04-01

234

Process for producing benzene by hydrodealkylation of a hydrocarbon fraction comprising alkylaromatic hydrocarbons, olefinic hydrocarbons and sulfur compound  

SciTech Connect

A stabilized hydrocarbon fraction comprising toluene, xylene, sulfur and olefinic hydrocarbons is converted to benzene by catalytic hydrodesulfurization, hydrodealkylation and catalytic hydrogenation.

Derrien, M.; Cosyns, J.

1984-07-31

235

Insertion of elemental sulfur and SO{sub 2} into the metal-hydride and metal-carbon bonds of platinum compounds  

SciTech Connect

Elemental sulfur (S{sub 8}) has been found to insert only one sulfur atom into the metal-hydride bonds of the platinum alkyl and aryl hydride complexes [(dcpe)PtRH] (dcpe = Cy{sub 2}PC{sub 2}H{sub 4}-PCy{sub 2}). Unlike the parent compounds, the S-inserted complexes do not undergo reductive elimination to form the corresponding alkane- or arenethiols. Methane is lost from the methyl sulfhydryl complex. Sulfur dioxide was also found to insert into a platinum-methyl bond to form the corresponding S-bound sulfinate, which upon reacting with mineral acids generates methylsulfinic acid.

Morton, M.S.; Lachicotte, R.J.; Vicic, D.A.; Jones, W.D. [Univ. of Rochester, NY (United States). Dept. of Chemistry

1999-01-18

236

Origin and diagenetic transformations of C sub 25 and C sub 30 highly branched isoprenoid sulfur compounds: Further evidence for the formation of organically bound sulfur during early diagenesis  

SciTech Connect

A number of C{sub 25} and C{sub 30} highly branched isoprenoid (HBI) sulfur compounds (e.g., thiolanes, 1-oxo-thiolanes, thiophenes, and benzo(b)thiophenes) with 2,6,10,14-tetramethyl-7-(3-methylpentyl)pentadecane and 2,6,10,14,18-pentamethyl-7-(3-methylpentyl)nonadecane carbon skeletons were identified in sediments, ranging from Holocene to Upper Cretaceous. These identifications are based on mass spectral characterization, desulfurization, and, in some cases, by comparison of mass spectral and relative retention time data with those of authentic standards. The presence of unsaturated C{sub 25} and C{sub 30} HBI thiolanes in a Recent sediment from the Black Sea (age 3-6 {times} 10{sup 3} a) strongly supports their formation during early diagenesis. The co-occurrence of HBI polyenes (C{sub 25} and C{sub 30}) and unsaturated HBI thiolanes (C{sub 25} and C{sub 30}) possessing two double bonds less than the corresponding HBI polyenes, in this Recent sediment, testifies to the formation of unsaturated HBI thiolanes by a reaction of inorganic sulfur species with double bonds of the HBI polyenes. Furthermore, a diagenetic scheme for HBI sulfur compounds is proposed based on the identification of HBI sulfur compounds in sediment samples with different maturity levels.

Kohnen, M.E.L.; Damste, J.S.S.; Kock-Van Dalen, A.C.; de Leeuw, J.W. (Delft Univ. of Technology (Netherlands)); Ten Haven, H.L.; Rullkoetter, J. (Institute of Petroleum and Organic Geochemistry, Juelich (West Germany))

1990-11-01

237

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

Code of Federal Regulations, 2013 CFR

... false National primary ambient air quality standards for sulfur oxides (sulfur dioxide...NATIONAL PRIMARY AND SECONDARY AMBIENT AIR QUALITY STANDARDS § 50.17 National primary ambient air quality standards for sulfur oxides (sulfur...

2013-07-01

238

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

Code of Federal Regulations, 2013 CFR

... false National primary ambient air quality standards for sulfur oxides (sulfur dioxide...NATIONAL PRIMARY AND SECONDARY AMBIENT AIR QUALITY STANDARDS § 50.4 National primary ambient air quality standards for sulfur oxides (sulfur...

2013-07-01

239

Use of a Novel Fluorinated Organosulfur Compound To Isolate Bacteria Capable of Carbon-Sulfur Bond Cleavage  

PubMed Central

The vacuum residue fraction of heavy crudes contributes to the viscosity of these oils. Specific microbial cleavage of CS bonds in alkylsulfide bridges that form linkages in this fraction may result in dramatic viscosity reduction. To date, no bacterial strains have been shown conclusively to cleave CS bonds within alkyl chains. Screening for microbes that can perform this activity was greatly facilitated by the use of a newly synthesized compound, bis-(3-pentafluorophenylpropyl)-sulfide (PFPS), as a novel sulfur source. The terminal pentafluorinated aromatic rings of PFPS preclude growth of aromatic ring-degrading bacteria but allow for selective enrichment of strains capable of cleaving CS bonds. A unique bacterial strain, Rhodococcus sp. strain JVH1, that used PFPS as a sole sulfur source was isolated from an oil-contaminated environment. Gas chromatography-mass spectrometry analysis revealed that JVH1 oxidized PFPS to a sulfoxide and then a sulfone prior to cleaving the CS bond to form an alcohol and, presumably, a sulfinate from which sulfur could be extracted for growth. Four known dibenzothiophene-desulfurizing strains, including Rhodococcus sp. strain IGTS8, were all unable to cleave the CS bond in PFPS but could oxidize PFPS to the sulfone via the sulfoxide. Conversely, JVH1 was unable to oxidize dibenzothiophene but was able to use a variety of alkyl sulfides, in addition to PFPS, as sole sulfur sources. Overall, PFPS is an excellent tool for isolating bacteria capable of cleaving subterminal CS bonds within alkyl chains. The type of desulfurization displayed by JVH1 differs significantly from previously described reaction results.

Van Hamme, Jonathan D.; Fedorak, Phillip M.; Foght, Julia M.; Gray, Murray R.; Dettman, Heather D.

2004-01-01

240

Preparation of organic sulfur adsorbent from coal for adsorption of dibenzothiophene-type compounds in diesel fuel  

SciTech Connect

High-performance organic sulfur adsorbents (OSA) have been prepared from coal by chemical activation for selective adsorption of the refractory sulfur compounds, such as 4-methyl dibenzothiophene and 4,6-dimethyldibenzothiophene, in diesel fuel. The performance of the prepared OSAs for adsorptive desulfurization (ADS) was evaluated in batch and flow adsorption systems at room temperature using a model diesel fuel. It was found that coal rank and preparation conditions, including activation agents (NaOH, KOH, and NaOH + KOH) and their ratio to coal, activation temperature, and time have significant impacts on the yield and ADS performance of the OSAs. The high-performance OSAs can be prepared from different ranks of coal by using NaOH + KOH as an activation agent with an activating-agent-to-coal ratio of 3.5. The yield of OSA increased in the order of lignite < high volatile bituminous coal < medium volatile bituminous coal < anthracite. The OSA-A, which was derived from an anthracite with the highest yield (68 wt %) by the activation at 650{sup o}C for 1 h, gave the best ADS performance among the OSAs from all coal samples tested. The sulfur adsorption capacity of OSA-A reached 0.281 mmol-S/g-A at an equilibrium sulfur concentration of 50 ppmw in the model diesel fuel, which was 155% higher than a commercial coal-derived activated carbon and 35% higher than the best commercial activated carbon among all commercial activated carbons examined in our laboratory. The higher ADS capacity of OSA-A can be attributed to its significantly higher density (2.77 {mu}mol/m{sup 2}) of the adsorption sites on the surface as determined by Langmuir adsorption isotherm, which is related to its oxygen-containing functional groups on the carbonaceous surface as revealed by temperature-programmed desorption analysis. 57 refs., 10 figs., 6 tabs.

Cigdem Shalaby; Xiaoliang Ma; Anning Zhou; Chunshan Song [Pennsylvania State University, University Park, PA (United States). Clean Fuels and Catalysis Program, EMS Energy Institute

2009-05-15

241

Bacterial Taxa That Limit Sulfur Flux from the Ocean  

Microsoft Academic Search

Flux of dimethylsulfide (DMS) from ocean surface waters is the predominant natural source of sulfur to the atmosphere and influences climate by aerosol formation. Marine bacterioplankton regulate sulfur flux by converting the precursor dimethylsulfoniopropionate (DMSP) either to DMS or to sulfur compounds that are not climatically active. Through the discovery of a glycine cleavage T-family protein with DMSP methyltransferase activity,

Erinn C. Howard; James R. Henriksen; Alison Buchan; Chris R. Reisch; Helmut Brgmann; Rory Welsh; Wenying Ye; Jos M. Gonzlez; Kimberly Mace; Samantha B. Joye; Ronald P. Kiene; William B. Whitman; Mary Ann Moran

2006-01-01

242

Relationship between corrosion and the biological sulfur cycle: A review  

SciTech Connect

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.

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

2000-04-01

243

Separation of elemental sulfur from hydrometallurgical residue: A review  

Microsoft Academic Search

Elemental sulfur in mining-related residues represents both a disposal challenge and a by-product opportunity. Sulfur and related sulfur compounds in aqueous environments result in acid generation and pH depression in water bodies. Recovery of sulfur from the residue could not only mitigate the volume and reactivity of the residues but may present opportunities in its sale. As a result, many

J. E. Halfyard; K. Hawboldt

2011-01-01

244

Flame photometric detection of phosphorus-alkyl and sulfur-alkyl compounds  

SciTech Connect

Verification of compliance with a chemical weapons treaty will require the collection of a large volume of wipe samples from potentially contaminated vessels, pipes, and other surfaces at facilities involved in the production, consumption, storage, transportation, and destruction of Schedule 1-4 chemicals. Subsequent on-site and off-site labor-intensive laboratory analysis of these samples will then be required. Phosphorus and sulfur are present in a large number of Schedule 1-4 chemicals and are likely to be present in detectable quantities on surfaces contaminated with chemical-weapons-related materials. Detection of phosphorus and sulfur is widely carried out with a gas chromatograph equipped with a flame photometric detector (GC-FPD). This conventional method is inappropriate for screening areas for sampling at numerous locations within a facility because of the lack of portability caused by large size and weight and the need for large sources of carrier, air or oxygen, and hydrogen gases and electrical power. This research was undertaken to obtain a design and performance evaluation of a free-standing, mobile FPD system for screening sample locations to reduce the number of required wipe samples to a manageable volume.

Dugan, J.P. Jr.; McManus, G.J.; Motes, B.G. (Westinghouse Idaho Nuclear Co., Idaho Falls, ID (United States))

1991-11-01

245

The behavior of nitrifying sludge in presence of sulfur compounds using a floating biofilm reactor.  

PubMed

The tolerance, kinetic and oxidizing capability of a nitrifying sludge exposed to different initial concentrations of sulfide (1.7 to 18mg/L) was evaluated in batch experiments. A nitrifying sludge fed with ammonium and thiosulfate and produced in steady state conditions was used as inoculum. Sulfide induced a significant effect either on ammonium consumption rates or nitrite accumulation. In spite of the nitrifying kinetic was affected, the ammonium consumption efficiencies were close to 100%, with nitrate production yields around 1.0. The IC(50) value for ammonium oxidizing-process was 13mg/L of sulfide. Sulfide was oxidized in two steps: first sulfide was oxidized to elemental sulfur and afterward into sulfate. FISH oligonucleotide probes for Thiobacillusdenitrificans, Nitrosomonas spp., and Nitrobacter spp. were used in order to know if these bacteria were part of the microbial ecology. The obtained results showed that under nitrifying conditions are possible to carry out simultaneously two biological processes, nitrification and sulfur oxidation. PMID:20620047

Beristain-Cardoso, Ricardo; Gmez, Jorge; Mndez-Pampn, Ramn

2010-11-01

246

Fluorine-Induced Chemiluminescence Detection of Biologically Methylated Tellurium, Selenium, and Sulfur Compounds and Methyldithiocarbhydrazide as a Formaldehyde Derivatization Reagent  

NASA Astrophysics Data System (ADS)

The first part of this dissertation describes capillary chromatography coupled to a fluorine-induced chemiluminescence detector as a sensitive method by which biologically methylated metalloids can be determined in the presence of high concentrations of potentially interfering molecules. With a wide linear range and excellent sensitivity, this method was applied to the detection of dimethyl selenide (DMSe), dimethyl diselenide (DMDSe), and dimethyl telluride (DMTe), often found in biological environments in the presence of interfering methylated sulfur gases, such as methanethiol, dimethyl sulfide, dimethyl disulfide, and dimethyl trisulfide. Detection limits for DMSe, DMDSe, and DMTe were 30, 9, and 7 picograms, respectively. This DMTe detection limit is the lowest reported to date for a volatile tellurium gas. A variety of selenium-resistant bacteria emitted mixtures of methylated sulfur/selenium gases when dosed with inorganic selenium salts in the presence of sulfur containing growth media. One of the gases detected was dimethyl selenenyl sulfide, CH_3SeSCH _3, reported here for the first time in headspace above microorganisms. In addition, this detector responded to reduced phosphorus compounds such as phosphine. The detection limit for this compound was 2.8 picograms. Detection limits for alkylated phosphines trimethyl and triethyl phosphine were 0.5 and 17 picograms respectively, based on the relative response of these compounds compared to dimethyl sulfide. This method can be used for the simultaneous determination of methylated sulfur, selenium, tellurium compounds found in biological systems. Part II of this dissertation describes work with methyldithiocarbhydrazide, a compound that has been synthesized for use as a derivatization reagent to capture formaldehyde in the gas phase. Chosen for its ability to react in a manner similar to 2,4-dinitrophenylhydrazine, this molecule was selected based on two structural characteristics: a hydrazine tag to react with and thereby capture carbonyls and a methyl sulfide group to allow for sensitive detection by fluorine-induced chemiluminescence. Although in the final analysis methyldithiocarbohydrazide failed as a successful means by which formaldehyde can be determined using gas chromatography in conjunction with fluorine-induced chemiluminescence, it did successfully derivatize formaldehyde in both solution and the gas phase without the need for low pH conditions.

Chasteen, Thomas Girard

1990-01-01

247

Process for removing sulfur from sulfur-containing gases  

DOEpatents

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.

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

1989-01-01

248

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

Microsoft Academic Search

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

R. D. Vetter

1985-01-01

249

Conversion of Enriched Isotopes of Sulfur from SF6 to a Suitable Compound for Feed to the Electromagnetic Calutron Separators  

Microsoft Academic Search

Enriched isotopes of sulfur are becoming attractive for use as tracers in a variety of environmental and scientific experiments. Many stages of separation are needed, especially for 33S and 36S, which exist in low natural abundances. Small amounts of highly enriched sulfur isotopes can be provided by means of electromagnetic separation in the calutrons. However, the cost is prohibitively high

H. H. Caudill; W. D. Bond; E. D. Collins; L. E. McBride; H. T. Milton; J. G. Tracy; A. M. Veach; J. W. York

1990-01-01

250

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

SciTech Connect

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.

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

1990-08-01

251

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

SciTech Connect

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.

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

1990-08-01

252

Sulfur-Oxygen Processes on Io.  

National Technical Information Service (NTIS)

Laboratory studies of irradiated sulfur dioxide frost have found that sulfur trioxide should be formed as a consequence of the irradiation process. The spectral reflectance of solid sulfur trioxide was measured in the laboratory and it was found that the ...

R. M. Nelson W. D. Smythe

1987-01-01

253

Possible interferences of mercury sulfur compounds with ethylated and methylated mercury species using HPLC-ICP-MS.  

PubMed

The HPLC-ICP-MS coupling technique is able to separate and detect methyl, ethyl and inorganic mercury isotopes specifically. An identification of ethyl mercury(+) is not possible when the widely used sodium tetraethylborate derivatisation method in combination with GC-AFS/AAS or ICP-MS techniques is performed because it contains ethyl groups.An unidentified compound with the same retention time as ethyl mercury was found in the HPLC chromatograms of industrial sewage samples and humic-rich soils of microcosm experiments after applying water vapour distillation. We also observed such unidentified peaks in samples of heavily contaminated sites in Eastern Germany, separated by HPLC fractionation only. In the experiments described, different mercury sulfur adducts were synthesised and tested for their retention times in the HPLC-ICP-MS system. It was found that the compound CH(3)-S-Hg(+) showed the same retention time as the ethyl mercury standard. It is therefore possible that ethyl mercury detected in chromatography by comparison of the retention time could also be due to an adduct of a sulfur compound and a mercury species. CH(3)-S-Hg(+ )should be tested in other chromatographic mercury speciation methods for this effect. This work can also be regarded as a contribution to the discussion of artificially occurring methyl mercury in sediments during sample preparation. PMID:12879205

Wilken, R-D; Nitschke, F; Falter, R

2003-07-15

254

Investigation of sulfur removal using direct oxidation processes  

SciTech Connect

Refinery fuel gas streams typically contain sulfur compounds. The principle such compound is hydrogen sulfide: minor constituents are carbonyl sulfide and mercaptan sulfur. These sulfur species must be removed in order that refinery combustion processes meet emission limitations imposed by regulatory authorities. Usually these fuel gas streams are low pressure. Choices for sulfur removal technology are constrained by the low pressure and the relatively low concentration of the sulfur species in the gas. The primary objective of this work is to identify applicable process technologies that might be employed to remove sulfur compounds and produce elemental sulfur directly. The methodology to investigate applicable processes consisted of the following steps: identify applicable technologies that are advanced beyond the research stage; review literature; query licensors to provide information on capital costs, utility requirements, chemical requirements, waste streams, and experience; and interview operators to ascertain actual experience with the process.

Pack, G.E.

1985-01-01

255

Demonstrating Allotropic Modifications of Sulfur.  

ERIC Educational Resources Information Center

|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)|

McCarty, Jillian L.; Dragojlovic, Veljko

2002-01-01

256

Volume efficient sodium sulfur battery  

DOEpatents

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.

Mikkor, Mati (Ann Arbor, MI)

1980-01-01

257

Evolution of Volatile Sulfur Compounds during Laboratory-Scale Incubations and Indoor Preparation of Compost Used as a Substrate in Mushroom Cultivation  

PubMed Central

Volatile sulfur compounds are known to be produced during the preparation of compost used as a substrate in mushroom cultivation. Because they cause odor problems, attempts have been made to reduce the production of these compounds. The influences of temperature and various additions on the production of volatile sulfur compounds from composting material were tested on laboratory-scale preparations. The production of H2S, COS, CH3SH, and (CH3)2S was proven to be a biological process with an optimal temperature that coincides with the optimal temperature for biological activity. The formation of CS2 and (CH3)2S2 was shown to be a nonbiological process. The emission of volatile sulfur compounds during the indoor preparation of mushroom compost appeared to be remarkably reduced (about 90%) as compared with the emission during the conventional outdoor process. Introduction of this indoor composting process would result in a significant reduction in environmental pollution.

Derikx, P. J. L.; Simons, F. H. M.; Op den Camp, H. J. M.; van der Drift, C.; Van Griensven, L. J. L. D.; Vogels, G. D.

1991-01-01

258

Clinical comparison of a new manual toothbrush on breath volatile sulfur compounds.  

PubMed

The objective of this randomized, crossover study was to compare the effectiveness of a newly designed manual toothbrush (Colgate 360 degrees) to two commercially available manual toothbrushes (Oral-B Indicator and Oral-B CrossAction) and a battery-powered toothbrush (Crest SpinBrush PRO) for their ability to reduce overnight volatile sulfur compounds (VSC) associated with oral malodor. The study followed a four-period crossover design. Following a washout period, prospective subjects arrived at the testing facility without eating, drinking, or performing oral hygiene for baseline evaluation of breath VSC levels. For each phase of the study, subjects were given one of the test tooth-brushes and a tube of regular toothpaste to take home, and they were instructed to brush their teeth in their customary manner for 1 minute. When using the Colgate 360 degrees toothbrush, subjects were instructed to clean their tongue with the implement on the back of the brush head for 10 seconds. The following morning, subjects reported to the testing facility, again without performing oral hygiene, eating, or drinking, for the overnight evaluation. After a minimum 2-day washout period, subjects repeated the same regimen using the other toothbrushes. The levels of breath VSC were evaluated instrumentally using a gas chromatograph equipped with a flame photometric detector. Measurements were taken in duplicate and then averaged. The levels of VSC were expressed as parts per billion (ppb) in mouth air. Sixteen men and women completed the study. At baseline, the mean levels of VSC in mouth air for the 4 toothbrushes were 719.8 ppb+/-318.4 ppb, 592.8 ppb+/-264.6 ppb, 673.8 ppb+/-405.9 ppb, and 656.2 ppb+/-310.2 ppb for the Colgate 360 degrees, Oral-B Indicator, Crest SpinBrush PRO, and Oral-B CrossAction, respectively. Overnight, the mean breath VSC levels after using the four toothbrushes were lower than those observed at baseline. The respective mean levels of breath VSC were 266.5 ppb+/-269.9 ppb, 545.2 ppb+/-346.1 ppb, 567 ppb+/-335.7 ppb, and 554.6 ppb+/-398.4 ppb. Only the Colgate 360 degrees toothbrush provided a statistically significant reduction (P < .05) in breath VSC vs baseline. Additionally, the Colgate 360 degrees toothbrush was statistically significantly better (P < .05) than the three commercial toothbrushes in reducing breath VSC. Therefore, the results of this randomized, crossover clinical study indicate that a newly designed manual toothbrush with a tongue-cleaning implement on the back of the brush head was significantly more effective than three commercially available toothbrushes in reducing morning breath VSC associated with oral malodor. PMID:15789979

Williams, Malcolm I; Vazquez, Joe; Cummins, Diane

2004-10-01

259

Assessment of sulfur removal processes for advanced fuel cell systems  

NASA Astrophysics Data System (ADS)

The performance characteristics of potential sulfur removal processes were evaluated and four of these processes, the Selexol process, the Benfield process, the Sulfinol process, and the Rectisol process, were selected for detailed technical and economic comparison. The process designs were based on a consistent set of technical criteria for a grass roots facility with a capacity of 10,000 tons per day of Illinois No. 6 coal. Two raw gas compositions, based on oxygen blown and air blown Texaco gasification, were used. The bulk of the sulfur was removed in the sulfur removal unit, leaving a small amount of sulfur compounds in the gas. The remaining sulfur compounds were removed by reaction with zinc oxide in the sulfur polishing unit. The impact of COS hydrolysis pretreatment on sulfur removal was evaluated. Comprehensive capital and O and M cost estimates for each of the process schemes were developed.

Lorton, G. A.

1980-01-01

260

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

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

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

2010-01-01

261

The purification of elemental sulfur  

SciTech Connect

Sulfur has been purified by a dynamic pyrolysis procedure that takes into account the unique viscosity-temperature relationship of the liquid. An apparatus is described that incorporates gas-bubbling and rocking to overcome diffusion-limited kinetics. For the first time, a mechanism is proposed for the pyrolytic purification of sulfur based upon Carsul formation and the H{sub 2}S{leftrightarrow}H{sub 2}S{sub {ital x}} equilibrium. Infrared methods are delineated for qualitative analysis and quantitative estimates of anion contaminants, including the omnipresent hydrocarbon impurities. Our purified sulfur has a total carbon, oxygen, and hydrogen impurity level of {lt}10 {mu}g/g.

Susman, S.; Rowland, S.C.; Volin, K.J. (Materials Science Division, Argonne National Laboratory, Argonne, Illinois 60439 (United States))

1992-06-01

262

Economic Impact of Revised Measurement Methods for Emissions of Sulfur Compounds, Proposed Regulations R87-31.  

National Technical Information Service (NTIS)

The study provides estimates of the economic impacts of proposed Illinois Pollution Control Board regulations governing measurement methods for sulfur dioxide emissions from coal-fired boilers in Illinois. The study also examines the methods used by facil...

F. T. DePaul J. Helm

1989-01-01

263

Effect of sulfur-containing compounds on growth of Methanosarcina barkeri in defined medium  

SciTech Connect

Methanosarcina barkeri Fusaro (DSM 804) could grow on methanol in a mineral medium containing cysteine or thiosulfate as the sole sulfur source. Optimum growth occurred at cysteine concentrations of 1 to 2.8 mM and at thiosulfate concentrations of 2.5 to 5 mM. No inhibition of growth was observed even when these concentrations were doubled in the culture medium. Under the optimum cysteine and thiosulfate concentrations, the generation times of the organism were about 8 to 10 and 10 to 12 h, respectively, giving a cell yield of about 0.14 to 0.17 and 0.08 to 0.11 g (dry weight)/g of methanol consumed. The organism metabolized cysteine and thiosulfate during growth, giving rise to sulfide in the culture medium. H/sub 2/S evolution from cysteine and thiosulfate was catalyzed by two enzymes, namely cysteine desulfhydrase and thiosulfate reductase, respectively, as revealed by enzyme assay in the crude cell-free extract of the organism.

Mazumder, T.K.; Nishio, N.; Fukuzaki, S.; Nagai, S.

1986-10-01

264

Production of sulfur from sulfur dioxide obtained from flue gas  

SciTech Connect

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.

Miller, R.

1989-06-06

265

New Limits on Sulfur in Combustion.  

National Technical Information Service (NTIS)

New regulation concerning the emission of sulfur from combustion plants are suggested in this report. The emission limits would be 0.05 g sulfur/MJ of fuel for plants emitting more than 400 tons of sulfur/year, and 0.10 g sulfur/MJ of fuel for plants emit...

1987-01-01

266

Sulfurization of carbon surface for vapor phase mercury removal I: Effect of temperature and sulfurization protocol  

Microsoft Academic Search

The uptake of hydrogen sulfide by carbon materials (ACFs and BPL) under dry and anoxic conditions was tested using a fixed bed reactor system to determine the effects of sorbent properties, temperature (200800C) and sulfurization protocols on the sulfur content, sulfur stability, sulfur distribution, and to elucidate possible reaction mechanisms for the formation of sulfur species. Sorbents with higher surface

Wenguo Feng; Eric Borguet; Radisav D. Vidic

2006-01-01

267

Io's Sulfur: Surface Distribution and Chemical Nature of Impurities  

NASA Astrophysics Data System (ADS)

Galileo SSI and NIMS data have returned a wealth of information on the surface composition of Io. Our analysis suggests that elemental sulfur and sulfur dioxide are nearly ubiquitous but that the ratio of these two materials varies widely. Some of the most spectacular concentrations of elemental sulfur occur near major volcanoes and hotspots. In these areas the color and spectral signature of sulfur and any other materials present varies widely, in some cases forming concentrically zoned deposits around calderas. The spectral variability of sulfur may be due to many mechanisms; inclusion of minor impurities is among the possible controls. We have made some tentative identifications of possible impurities-- iron (as opaque inclusions of FeS disseminated in sulfur) appears to cause the green coloration of some deposits on Io-- including Io's so-called "golf courses." Arsenic, selenium, and tellurium (dissolved in quenched sulfur polymers and/or bonded in stoichiometric compounds with sulfur) may contribute to reddish coloration of other deposits. As little as one percent of these impurities may produce marked changes in the spectral reflectance and color of sulfur. However, other mechanisms can account for Io's reds; Io's green deposits are harder to explain in the absence of pyrite or other metallic sulfide inclusions in elemental sulfur; the logical alternative, ultramafic silicates, has fallen out of favor with the Galileo team due to absence of a diagnostic band near 0.9 microns. These colored forms of impure sulfur have been observed both in nature (in terrestrial volcanogenic native sulfur) and in recent lab specimens quenched from the molten state and containing controlled quantities of impurities (cf abstract by MacIntyre et al., this volume). Evidence for impurities in Io's sulfur will be presented, and we will offer a glimpse into possible geological process implications of the distribution of sulfur on Io and the impurities that may be present in Io's sulfur.

Kargel, J. S.; MacIntyre, T.; Dalton, B.; Clark, R.

2000-10-01

268

Alkali metal/sulfur battery  

DOEpatents

Alkali metal/sulfur batteries in which the electrolyte-separator is a relatively fragile membrane are improved by providing means for separating the molten sulfur/sulfide catholyte from contact with the membrane prior to cooling the cell to temperatures at which the catholyte will solidify. If the catholyte is permitted to solidify while in contact with the membrane, the latter may be damaged. The improvement permits such batteries to be prefilled with catholyte and shipped, at ordinary temperatures.

Anand, Joginder N. (Clayton, CA)

1978-01-01

269

Process for production of synthesis gas with reduced sulfur content  

DOEpatents

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.

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

1989-01-01

270

Emission of sulfur from Lake Ontario sediments  

Microsoft Academic Search

Calculations indicate that about 6.0 x 10⁵ kg of sulfur is released annually from Lake Ontario sediments. This constitutes about 1% of the annual sulfur input into the sediments and is insignificant compared to the total sulfur that cycles annually through the lake. The sulfur released from the sediments is enriched in ³²S with the result that the sulfur in

J. O. Nriagu; R. D. Coker

1976-01-01

271

Thermophilic Carbon-Sulfur-Bond-Targeted Biodesulfurization  

PubMed Central

Petroleum contains many heterocyclic organosulfur compounds refractory to conventional hydrodesulfurization 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 (C--S) bonds in DBT at high temperatures, have been isolated for the first time. Upon attacking DBT and its various methylated derivatives at temperatures up to 60(deg)C, both growing and resting cells of these bacteria can release sulfur atoms as sulfate ions and leave the monohydroxylated hydrocarbon moieties intact. Moreover, when either of these paenibacilli was incubated at 50(deg)C with light gas oil previously processed through hydrodesulfurization, the total sulfur content in the oil phase clearly decreased.

Konishi, J.; Ishii, Y.; Onaka, T.; Okumura, K.; Suzuki, M.

1997-01-01

272

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

SciTech Connect

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.

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

1997-09-01

273

[An evaluation of acute effects of sulfur compounds for the human organism in natural gas fields emergencies (review)].  

PubMed

A trend towards a growing number of emergency situations at industrial enterprises has been recently traced throughout the world. The main reasons of such phenomenon are: a comprehensive use of highly dangerous technologies and materials; large-scale violations of the operational rules and norms; and an inadmissibly high wear-and-tear of the main production funds in economic branches with extra risk. The world experience is indicative of a high degree of danger related with exploiting the natural-gas fields with a high content of sulfur compounds. The occurrence of emergency situations in the mentioned fields is accompanied by development of acute and sub-acute toxic effects in the workers and population. It necessitated, recently, an elaboration of a concept of a relative safety, in view of an unfavorable impact produced by chemical substances in emergencies, and an elaboration of methods applicable to the evaluation of emergency regulations. PMID:12852038

Salikhova, L R; Zebseev, V V; Karpov, A I; Eremin, M N; Gorlov, A V

274

Adsorptive Removal of Organic Sulfur Compounds from Jet Fuel over K-exchanged NiY Zeolites Prepared by Impregnation and Ion Exchange  

SciTech Connect

NiY zeolites with different Ni loadings were synthesized by incipient wetness impregnation and liquid phase ion-exchange methods using NH4Y and KY zeolites. These Ni-containing Y zeolites were tested as adsorbents for removing organic sulfur compounds from a model jet fuel containing 510 ppmw sulfur and a real JP-8 jet fuel containing 380 ppmw sulfur under ambient conditions either without reduction or after reduction around 600 C. At the adsorption temperature of 80 C, the NiY zeolite containing 30 wt % Ni synthesized by incipient wetness impregnation of NH4Y zeolite was able to clean only about 10 ml of a model jet fuel per g of the adsorbent to produce a desulfurized fuel containing below 1 ppmw sulfur. Under the same experimental conditions, the NiY zeolite prepared using KY zeolite cleaned about 30 ml of the fuel per g of the adsorbent. Better sulfur adsorption performance was observed when the NiY zeolites were synthesized by ion-exchange, and reduced before sulfur adsorption. The reducibility and surface properties of some of the selected NiY zeolites were investigated by temperature-programmed reduction (TPR) and in-situ X-ray photoelectron spectroscopy (XPS). TPR studies indicated that the reducibility of NiY-zeolite was improved when K was present as a co-cation. The in-situ XPS studies of unreduced and reduced samples revealed that presence of K as co-cation in the zeolite matrix helps Ni dispersion at the surface. The promotional effect of K on the sulfur adsorption performance of NiY zeolites was therefore attributed to improved reducibility and surface dispersion of Ni when K was present as a co-cation.

Subramani, Velu; Song, Chunshan; Engelhard, Mark H.; Chin, Ya-Huei

2005-07-20

275

Metabolism of Reduced Methylated Sulfur Compounds in Anaerobic Sediments and by a Pure Culture of an Estuarine Methanogen  

PubMed Central

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 ?2-?M levels as [14C]DMS, metabolism by sediments resulted in a 14CH4/14CO2 ratio of only 0.06. Addition of molybdate increased the ratio to 1.8, while 2-bromoethanesulfonic acid decreased it to 0, but did not block 14CO2 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 [14C]-DMS to yield a 14CH4/14CO2 ratio of ?2.8. Reduced methylated sulfur compounds represent a new class of substrates for methanogens and may be potential precursors of methane in a variety of aquatic habitats.

Kiene, Ronald P.; Oremland, Ronald S.; Catena, Anthony; Miller, Laurence G.; Capone, Douglas G.

1986-01-01

276

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

NASA Astrophysics Data System (ADS)

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.

Porter, E.

2008-12-01

277

Quantitative proteomics of Chlorobaculum tepidum: insights into the sulfur metabolism of a phototrophic green sulfur bacterium.  

PubMed

Chlorobaculum (Cba.) tepidum is a green sulfur bacterium that oxidizes sulfide, elemental sulfur, and thiosulfate for photosynthetic growth. To gain insight into the sulfur metabolism, the proteome of Cba. tepidum cells sampled under different growth conditions has been quantified using a rapid gel-free, filter-aided sample preparation (FASP) protocol with an in-solution isotopic labeling strategy. Among the 2245 proteins predicted from the Cba. tepidum genome, approximately 970 proteins were detected in unlabeled samples, whereas approximately 630-640 proteins were detected in labeled samples comparing two different growth conditions. Wild-type cells growing on thiosulfate had an increased abundance of periplasmic cytochrome c-555 and proteins of the periplasmic thiosulfate-oxidizing SOX enzyme system when compared with cells growing on sulfide. A dsrM mutant of Cba. tepidum, which lacks the dissimilatory sulfite reductase DsrM protein and therefore is unable to oxidize sulfur globules to sulfite, was also investigated. When compared with wild type, the dsrM cells exhibited an increased abundance of DSR enzymes involved in the initial steps of sulfur globule oxidation (DsrABCL) and a decreased abundance of enzymes putatively involved in sulfite oxidation (Sat-AprAB-QmoABC). The results show that Cba. tepidum regulates the cellular levels of enzymes involved in sulfur metabolism and other electron-transferring processes in response to the availability of reduced sulfur compounds. PMID:22092713

Falkenby, Lasse G; Szymanska, Monika; Holkenbrink, Carina; Habicht, Kirsten S; Andersen, Jens S; Miller, Mette; Frigaard, Niels-Ulrik

2011-08-25

278

Smaller sulfur molecules promise better lithium-sulfur batteries.  

PubMed

The lithium-sulfur battery holds a high theoretical energy density, 4-5 times that of today's lithium-ion batteries, yet its applications have been hindered by poor electronic conductivity of the sulfur cathode and, most importantly, the rapid fading of its capacity due to the formation of soluble polysulfide intermediates (Li(2)S(n), n = 4-8). Despite numerous efforts concerning this issue, combatting sulfur loss remains one of the greatest challenges. Here we show that this problem can be effectively diminished by controlling the sulfur as smaller allotropes. Metastable small sulfur molecules of S(2-4) were synthesized in the confined space of a conductive microporous carbon matrix. The confined S(2-4) as a new cathode material can totally avoid the unfavorable transition between the commonly used large S(8) and S(4)(2-). Li-S batteries based on this concept exhibit unprecedented electrochemical behavior with high specific capacity, good cycling stability, and superior rate capability, which promise a practicable battery with high energy density for applications in portable electronics, electric vehicles, and large-scale energy storage systems. PMID:23101502

Xin, Sen; Gu, Lin; Zhao, Na-Hong; Yin, Ya-Xia; Zhou, Long-Jie; Guo, Yu-Guo; Wan, Li-Jun

2012-10-31

279

Production of ultra-low-sulfur gasoline: an equilibrium and kinetic analysis on adsorption of sulfur compounds over Ni/MMS sorbents.  

PubMed

High performance nickel-based micro-mesoporous silica (Ni/MMS) sorbent was prepared by incipient wetness impregnation with ultrasonic aid (IWI-u) for adsorptive desulfurization (ADS) of commercial gasoline and simulated fuels. The sorbents were characterized with BET, XRD, TPR, SEM, HRTEM and TG/DTG. These results show that 20 wt%Ni/MMS (IWI-u) can still retain the framework of MMS and nickel particles were homogeneously distributed in the MMS channels without any aggregation, which improved significantly the ADS performance of the sorbents. The studies on the ADS kinetics indicate that the adsorption behavior of thiophene (T), benzothiophene (BT) and dibenzothiophene (DBT) over 20 wt%Ni/MMS (IWI-u) can be described appropriately by pseudo second-order kinetic model. The intraparticle diffusion model verified that the steric hindrance and intraparticle diffusion were the rate controlling step of the adsorption process of DBT molecules. Langmuir model can be used to describe the adsorption isotherms for T, BT and DBT due to low coverage. The regeneration sorbent maintains the sulfur removal efficiency of 85.9% for 6 cycles. PMID:23022413

Subhan, Fazle; Liu, B S; Zhang, Q L; Wang, W S

2012-09-14

280

Are we getting enough sulfur in our diet?  

PubMed Central

Sulfur, after calcium and phosphorus, is the most abundant mineral element found in our body. It is available to us in our diets, derived almost exclusively from proteins, and yet only 2 of the 20 amino acids normally present in proteins contains sulfur. One of these amino acids, methionine, cannot be synthesized by our bodies and therefore has to be supplied by the diet. Cysteine, another sulfur containing amino acid, and a large number of key metabolic intermediates essential for life, are synthesized by us, but the process requires a steady supply of sulfur. Proteins contain between 3 and 6% of sulfur amino acids. A very small percentage of sulfur comes in the form of inorganic sulfates and other forms of organic sulfur present in foods such as garlic, onion, broccoli, etc. The minimal requirements (RDA) for all the essential amino acids have always been estimated in terms of their ability to maintain a nitrogen balance. This method asses amino acid requirements for protein synthesis, only one of the pathways that methionine follows after ingestion. To adequately evaluate the RDA for methionine, one should perform, together with a nitrogen balance a sulfur balance, something never done, neither in humans nor animals. With this in mind we decided to evaluate the dietary intake of sulfur (as sulfur amino acids) in a random population and perform sulfur balance studies in a limited number of human volunteers. Initially this was done to try and gain some information on the possible mode of action of a variety of sulfur containing compounds (chondroitin sulfate, glucosamine sulfate, and others, ) used as dietary supplements to treat diseases of the joints. Out of this study came information that suggested that a significant proportion of the population that included disproportionally the aged, may not be receiving sufficient sulfur and that these dietary supplements, were very likely exhibiting their pharmacological actions by supplying inorganic sulfur.

Nimni, Marcel E; Han, Bo; Cordoba, Fabiola

2007-01-01

281

Organic sulfur compounds resulting from the interaction of iron sulfide, hydrogen sulfide and carbon dioxide in an anaerobic aqueous environment.  

PubMed

The reaction of iron sulfide (FeS) with H2S in water, in presence of CO2 under anaerobic conditions was found to yield H2 and a variety of organic sulfur compounds, mainly thiols and small amounts of CS2 and dimethyldisulfide. The same compounds were produced when H2S was replaced by HCl, in the H2S-generating system FeS/HCl/CO2. The identification of the products was confirmed by GC-MS analyses and the incorporation of H2 in the organic sulfur compounds was demonstrated by experiments in which all hydrogen compounds were replaced by deuterium compounds. Generation of H2 and the synthesis of thiols were both dependent upon the relative abundance of FeS and HCl or H2S, i.e. the FeS/HCl- or FeS/H2S-proportions. Whether thiols or CS2 were formed as the main products depended also on the FeS/HCl-ratio: All conditions which create a H2 deficiency were found to initiate a proportional increase in the amount of CS2. The quantities of H2 and thiols generated depended on temperature: the production of H2 was significantly accelerated from 50 degrees C onward and thiol synthesis above 75 degrees C. The yield of thiols increased with the amount of FeS and HCl (H2S), given a certain FeS/HCl-ratio and a surplus of CO2. A deficiency of CO2 results in lower thiol synthesis. The end product, pyrite (FeS2), was found to appear as a silvery granular layer floating on the aqueous surface. The identity of the thiols was confirmed by mass spectrometry, and the reduction of CO2 demonstrated by the determination of deuterium incorporation with DCl and D2O. The described reactions can principally proceed under the conditions comparable to those obtaining around submarine hydrothermal vents, or the global situation about 4 billion years ago, before the dawn of life, and could replace the need for a reducing atmosphere on the primitive earth. PMID:11536750

Heinen, W; Lauwers, A M

1996-04-01

282

Process for the removal of sulfur oxides  

Microsoft Academic Search

Sulfur oxides are removed from waste gases containing the same by scrubbing the waste gas with an aqueous scrubbing solution containing the aluminate of sodium, potassium or ammonium, and an additional compound selected from the group consisting of aluminum sulfate and alum.

T. Takeyama; A. Takahashi; K. Matsumura; K. Kitagawa

1979-01-01

283

Sulfur recovery in a coal gasification plant  

Microsoft Academic Search

To determine the most economical combination of processes for removing sulfur compounds from a coal gasification plant's gasifier raw gas and boiler flue gas, C. F. Braun and Co. examined alternatives for a 250 million cu ft\\/day plant using the Bituminous Coal Research Inc. Bi-Gas gasification process. For a western coal feed, the combination of a nonselective Selexol process for

W. S. Chia; F. A. Todd; W. J. Stupin

1978-01-01

284

Sulfur Oxidation at Deep-Sea Hydrothermal Vents  

Microsoft Academic Search

Microbial oxidation of geothermally produced reduced sulfur compounds is at the nexus of the biogeochemical carbon and sulfur\\u000a cycles at deep-sea hydrothermal vents. Available information indicates that microbial symbionts and free- living gammaproteobacteria\\u000a of the genera Thiomicrospira, Halothiobacillus, and Beggiatoa are important sulfur-oxidizers above the seafloor at these systems. In addition, bacteria belonging to the Epsilonproteobacteria have been identified as

Stefan M. Sievert; Michael Hgler; Craig D. Taylor; Carl O. Wirsen

285

Characterization and quantification of the oxides of sulfur and nitrogen and associated compounds in their gaseous, aerosol, and dissolved states  

SciTech Connect

The needs and problems associated with the characterization and quantification of the oxides of sulfur and nitrogen and associated compounds in their gaseous, aerosol, and dissolved states are discussed. Illustrations are given of the techniques in present usage for the determination of the substances of interest to investigators concerned with the effects of air pollutants on the terrestrial ecosystem. The value and utility of the newer techniques employing real time continuous instrumentation are presented and compared with the more traditional approaches utilizing sampling collection. A plea is made to provide resources for data reduction especially in order to obtain constructive utilization of continuous instrumentation. It is asserted that real time instrumentation is best utilized during campaign measurement programs where short time resolution is required and that collection techniques still have a place, especially in long term monitoring efforts. Special attention was directed at, and the problems highlighted that are associated with, the utilization of the real time instruments available for the flame photometric determination of the oxides of sulfur and the chemiluminescent measurement of the oxides of nitrogen. The newer methods proposed for their use in the determination of sulfate and nitric acid respectively are presented. The difficulties associated with the determination of nitrate are enunciated and attention focused on the problems of obtaining a sample due to the variation of the vapor pressure of gaseous nitric acid and ammonia above solid ammonium nitrate which is in association with an acidic aerosol containing sulfate. The utility of measurements of the composition of rainwater is discussed in light of its application to determine the mechanisms through which rain derives its chemical composition.

Newman, L

1980-05-01

286

Structural analyses of the permease like protein SoxT: a member of the sulfur compound metabolizing sox operon.  

PubMed

One of the oldest known gene clusters that are involved in biological oxidation processes is the sox operon. This operon is present in different microbial species. In the present study an attempt has been made to analyze the probable structural role of SoxT protein from Pseudaminobacter salicylatoxidans. This protein has been predicted to be a permease-like protein. A comparative model of the protein has been made and analyzed. The possible membrane spanning region of the protein has been detected by structural bioinformatics approach. The inducer of the sulfur oxidation process has been predicted. And thereby the plausible mechanism of the transport of the sulfur anion inside the bacterial cell has been elucidated. Since this is the first study regarding the structural aspect of the protein this study may shed light on the theory of the yet unknown molecular mechanism of the sulfur oxidation process by sox operon. PMID:23500599

Bagchi, Angshuman

2013-03-14

287

Intermediate sulfur oxidation state compounds in the euxinic surface sediments of the Dvurechenskii mud volcano (Black Sea)  

NASA Astrophysics Data System (ADS)

The deep Black Sea is known to be depleted in electron-acceptors for sulfide oxidation. This study on depth distributions of sulfur species (S(II), S(0), Sn2-, SO32-, SO32-, SO42-) in the Dvurechenskii mud volcano, a cold seep situated in the permanently anoxic eastern Black Sea basin (Sorokin Trough, 2060 m water depth), showed remarkable concentrations of sulfide oxidation products. Sulfite concentrations of up to 11 ?mol L-1, thiosulfate concentrations of up to 22 ?mol L-1, zero-valent sulfur concentrations of up to 150 ?mol L-1 and up to five polysulfide species were measured in the upper 20 cm of the sediment. Electron-acceptors found to be available in the Dvurechenskii mud volcano (DMV) for the oxidation of hydrogen sulfide to sulfide oxidation intermediates are iron-minerals, and probably also reactive manganese phases. Up to 60 ?mol g-1 of reactive iron-minerals and up to 170 ?mol L-1 dissolved iron was present in the central summit with the highest fluid upflow and fresh mud outflow. Thus, the source for the oxidative power in the DMV are reactive iron phases extruded with the mud from an ancient source in the deeply buried sediments, leading to the formation of various sulfur intermediates in comparably high concentrations. Another possible source of sulfide oxidation intermediates in DMV sediments could be the formation of zero-valent sulfur by sulfate dependent anaerobic microbial oxidation of methane followed by disproportionation of zero-valent sulfur. Sulfide oxidation intermediates, which are produced by these processes, do not reach thermodynamic equilibrium with rhombic sulfur, especially close to the active center of the DMV due to a short equilibration time. Thus, mud volcano sediments, such as in the DMV, can provide oxidizing niches even in a highly reduced environment like the abyssal part of the Black Sea.

Lichtschlag, Anna; Kamyshny, Alexey; Ferdelman, Timothy G.; deBeer, Dirk

2013-03-01

288

Biochemistry of Dissimilatory Sulfur Oxidation  

SciTech Connect

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 methods. The conclusion is that the thiobacilli appear to express specific receptors that enable the bacteria to recognize and adhere to insoluble sulfur. The enzyme tetrathionate oxidase was purified from two species of the thiobacilli. Extensive structural and functional studies were conducted on adenosine 5'-phosphosulfate reductase purified from cell-free extracts of Thiobacillus denitrificans. The kinetic mechanism of rhodanese was studied.

Blake II, R.

2003-05-30

289

Identification of organic sulfur compounds in coal bitumen obtained by different extraction techniques using comprehensive two-dimensional gas chromatography coupled to time-of-flight mass spectrometric detection  

Microsoft Academic Search

The determination of organic sulfur compounds (OSC) in coal is of great interest. Technically and operationally these compounds\\u000a are not easily removed and promote corrosion of equipment. Environmentally, the burning of sulfur compounds leads to the emission\\u000a of SO\\u000a x\\u000a gases, which are major contributors to acid rain. Health-wise, it is well known that these compounds have mutagenic and carcinogenic

Maria Elisabete Machado; Fernando Cappelli Fontanive; Jos Vladimir de Oliveira; Elina Bastos Caramo; Cludia Alcaraz Zini

290

Microbial Desulfurization of a Crude Oil Middle-Distillate Fraction: Analysis of the Extent of Sulfur Removal and the Effect of Removal on Remaining Sulfur  

PubMed Central

Rhodococcus sp. strain ECRD-1 was evaluated for its ability to desulfurize a 232 to 343C middle-distillate (diesel range) fraction of Oregon basin (OB) crude oil. OB oil was provided as the sole source of sulfur in batch cultures, and the extent of desulfurization and the chemical fate of the residual sulfur in the oil after treatment were determined. Gas chromatography (GC), flame ionization detection, and GC sulfur chemiluminesce detection analysis were used to qualitatively evaluate the effect of Rhodococcus sp. strain ECRD-1 treatment on the hydrocarbon and sulfur content of the oil, respectively. Total sulfur was determined by combustion of samples and measurement of released sulfur dioxide by infrared absorption. Up to 30% of the total sulfur in the middle distillate cut was removed, and compounds across the entire boiling range of the oil were affected. Sulfur K-edge X-ray absorption-edge spectroscopy was used to examine the chemical state of the sulfur remaining in the treated OB oil. Approximately equal amounts of thiophenic and sulfidic sulfur compounds were removed by ECRD-1 treatment, and over 50% of the sulfur remaining after treatment was in an oxidized form. The presence of partially oxidized sulfur compounds indicates that these compounds were en route to desulfurization. Overall, more than two-thirds of the sulfur had been removed or oxidized by the microbial treatment.

Grossman, M. J.; Lee, M. K.; Prince, R. C.; Garrett, K. K.; George, G. N.; Pickering, I. J.

1999-01-01

291

Kinetics of Sulfur Oxide, Sulfur Fluoride, and Sulfur Oxyfluoride Anions with Atomic Species at 298 and 500 K.  

National Technical Information Service (NTIS)

The rate constants and product-ion branching ratios for the reactions of sulfur dioxide (SO2(-)), sulfur fluoride (SF(n)-), and sulfur oxyfluoride anions (SO(x)F(y)) with H, H2, N, N2, NO, and 0 have been measured in a selected-ion flow tube (SIFT). H ato...

A. A. Viggiano A. J. Midey

2007-01-01

292

Sulfur Volatiles in the Early Martian Atmosphere  

NASA Astrophysics Data System (ADS)

Our modeling indicates a high sulfur solubility in martian mantle melts and suggests that sulfur volatile pulses associated with large, discreet volcanic events during the late Noachian may have significantly warmed the atmosphere.

Johnson, S. S.; Zuber, M. T.; Grove, T. L.; Pavlov, A. A.; Mischna, M. A.

2007-03-01

293

Oceanic emissions of sulfur: Application of new techniques  

Microsoft Academic Search

Sulfur gases and aerosols are important in the atmosphere because they play major roles in acid rain, arctic haze, air pollution, and climate. Globally, man-made and natural sulfur emissions are comparable in magnitude. The major natural source is dimethyl sulfide (DMS) from the oceans, where it originates from the degradation of dimethysulfonioproprionate (DMSP), a compound produced by marine phytoplankton. Global

Clara Mary Jodwalis

1998-01-01

294

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...

295

Grapevine & Sulfur: Old Partners, New Achievements  

Microsoft Academic Search

The central role of sulfur in biological functions Sulfur (S) is the 14th more abundant element on earth crust (Charlson et\\u000a al. 1992), the 9th and least abundant essential macronutrient in plants (Saito 2004) and the 6th element in the cytoplasm\\u000a (Xavier and LeGall 2007). The interconversion of oxidized and reduced sulfur states, the biogeochemical sulfur cycle, depends\\u000a mainly on

S. Amncio; S. Tavares; J. C. Fernandes; C. Sousa

296

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

PubMed Central

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.

Tabe, Linda M.; Droux, Michel

2002-01-01

297

Formation of insoluble, nonhydrolyzable, sulfur-rich macromolecules via incorporation of inorganic sulfur species into algal carbohydrates  

NASA Astrophysics Data System (ADS)

The process of sulfur incorporation into organic matter was simulated in the laboratory by sulfurization of cell material of the prymnesiophyte alga Phaeocystis in sea water with inorganic polysulfides at 50C. Flash pyrolysis of the residue, obtained after extraction and several hydrolysis steps, yielded mainly C 1-C 4 alkylbenzenes and C 1-C 4 alkylphenols and, in contrast to control and blank experiments, relatively high amounts of C 0-C 4 alkylthiophenes. The distribution of the thiophenes is very similar to that in pyrolysates of type II-S kerogens. The formation of high-molecular-weight sulfur-rich macromolecules co-occurs with a marked drop in the content of hydrolyzable carbohydrates. This indicates that sulfurization results in the preservation of algal carbohydrate carbon in a macromolecular structure composed of (poly)sulfidic cross-linked carbohydrate skeletons, which upon pyrolysis yields alkylthiophenes. Sulfurization of glucose under similar conditions resulted in the formation of a nonhydrolyzable, solid material, which yielded high amounts of organic sulfur compounds upon pyrolysis, mainly short-chain alkylthiophenes, although with a different distribution than that in the pyrolysate of the sulfurized algal material. The carbon numbers of these organic sulfur compounds extend beyond six, indicating that the length of the carbon skeleton of the pyrolysis products is not limited by the length of the carbon skeleton of the substrate. These results suggest that the sulfurization of carbohydrates may be an important pathway in the preservation of organic matter in euxinic depositional environments.

Kok, Marika D.; Schouten, Stefan; Sinninghe Damst, Jaap S.

2000-08-01

298

Swept Away: Resuspension of Bacterial Mats Regulates Benthic-Pelagic Exchange of Sulfur  

NASA Astrophysics Data System (ADS)

Filaments and extracellular material from colorless sulfur bacteria (Beggiatoa spp.) form extensive white sulfur mats on surface sediments of coastal, oceanic, and even deep-sea environments. These chemoautotrophic bacteria oxidize soluble reduced sulfur compounds and deposit elemental sulfur, enriching the sulfur content of surface sediment fivefold over that of deeper sediments. Laboratory flume experiments with Beggiatoa mats from an intertidal sandflat (Nova Scotia) demonstrated that even slight erosion of sediment causes a flux of 160 millimoles of sulfur per square meter per hour, two orders of magnitude greater than the flux produced by sulfur transformations involving either sulfate reduction or sulfide oxidation by benthic bacteria. These experiments indicate that resuspension of sulfur bacterial mats by waves and currents is a rapid mechanism by which sediment sulfur is recycled to the water column. Benthic communities thus lose an important storage intermediate for reduced sulfur as well as a high-quality bacterial food source for benthic grazers.

Grant, Jonathan; Bathmann, Ulrich V.

1987-06-01

299

46 CFR 153.1046 - Sulfuric acid.  

Code of Federal Regulations, 2011 CFR

...2011-10-01 2011-10-01 false Sulfuric acid. 153.1046 Section 153.1046 Shipping...Cargo Procedures § 153.1046 Sulfuric acid. No person may liquefy frozen or congealed sulfuric acid other than by external tank heating...

2011-10-01

300

46 CFR 153.1046 - Sulfuric acid.  

Code of Federal Regulations, 2012 CFR

...2012-10-01 2012-10-01 false Sulfuric acid. 153.1046 Section 153.1046 Shipping...Cargo Procedures § 153.1046 Sulfuric acid. No person may liquefy frozen or congealed sulfuric acid other than by external tank heating...

2012-10-01

301

Genetic engineering of sulfur-degrading Sulfolobus  

SciTech Connect

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.

Ho, N.W.Y.

1991-01-01

302

Air Quality Criteria for Sulfur Oxides.  

ERIC Educational Resources Information Center

|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

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

303

Chemical removal of pyritic sulfur from coal  

Microsoft Academic Search

A new approach for the chemical removal of pyritic sulfur from coal is described. The process is based on the discovery that aqueous ferric salt selectively oxidizes the pyritic sulfur in coal to chemical forms which can be removed by vaporization, steam, or solvent extraction. Data for removal of the pyritic sulfur from four major coals (Lower Kittanning, Illinois No.

J. W. Hamersma; M. L. Kraft; E. P. Koutsoukos; R. A. Meyers

1976-01-01

304

TRENDS IN RURAL SULFUR CONCENTRATIONS  

EPA Science Inventory

This paper presents an analysis of regional trends in atmospheric concentrations in sulfur dioxide (502) and particulate sulfate (50~- ) at rural monitoring sites in the Clean Air Act Status and Trends Monitoring Network (CAsTNet) from 1990 to 1999. A two-stage approach is used t...

305

Sulfur Dioxide and Material Damage  

ERIC Educational Resources Information Center

|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)|

Gillette, Donald G.

1975-01-01

306

Seal for sodium sulfur battery  

DOEpatents

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.

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

1980-01-01

307

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...

308

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

SciTech Connect

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.

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

2012-01-14

309

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

NASA Astrophysics Data System (ADS)

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.

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

2012-01-01

310

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

Microsoft Academic Search

\\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

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

311

Genomics of alternative sulfur utilization in ascomycetous yeasts.  

PubMed

Thirteen ascomycetous yeast strains with sequenced genomes were assayed for their ability to grow on chemically defined medium with 16 different sulfur compounds as the only significant source of sulfur. These compounds included sulfoxides, sulfones, sulfonates, sulfamates and sulfate esters. Broad utilization of alternative sulfur sources was observed in Komagataella pastoris (syn. Pichia pastoris), Lodderomyces elongisporus, Millerozyma farinosa (syn. Pichia sorbitophila), Pachysolen tannophilus, Scheffersomyces stipitis (syn. Pichia stipitis), Spathaspora passalidarum, Yamadazyma tenuis (syn. Candida tenuis) and Yarrowia lipolytica. Kluyveromyces lactis, Saccharomyces cerevisiae and Zygosaccharomyces rouxii were mainly able to utilize sulfonates and sulfate esters, while Lachancea thermotolerans and Schizosaccharomyces pombe were limited to aromatic sulfate esters. Genome analysis identified several candidate genes with bacterial homologues that had been previously shown to be involved in the utilization of alternative sulfur sources. Analysis of candidate gene promoter sequences revealed a significant overrepresentation of DNA motifs that have been shown to regulate sulfur metabolism in Sacc. cerevisiae. PMID:22790398

Linder, Tomas

2012-07-12

312

Comparison of breath and in-mouth collection for the measurement of oral malodorous compounds by gas chromatography using sulfur chemiluminescence detection.  

PubMed

Volatile sulfur compounds (VSCs), specifically hydrogen sulfide, methyl mercaptan and dimethyl sulfide, are generally considered to be the primary volatiles responsible for 'morning' malodors in breath. To date, the 'gold standard' for detecting VSC concentrations in breath is the use of gas chromatography coupled with sulfur chemiluminescence detection. Breath gas is often collected in a polypropylene syringe and then aliquots are injected into a gas chromatograph for analysis. The objective of this work was to compare the Twister bar in-mouth extraction methodology for measurement of VSCs with the gas syringe breath-sampling collection technique. The Twister bar technology captures malodorous compounds in the mouth as opposed to breath gas. Using these techniques, comparable results were obtained in studies demonstrating the efficacy of a proprietary oral malodor counteraction system. PMID:21386211

Paetznick, Debbie J; Reineccius, G A; Peppard, T L; Herkert, J M; Lenton, P

2010-02-18

313

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

PubMed Central

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.

Aussignargues, Clement; Giuliani, Marie-Cecile; Infossi, Pascale; Lojou, Elisabeth; Guiral, Marianne; Giudici-Orticoni, Marie-Therese; Ilbert, Marianne

2012-01-01

314

Assimilatory sulfur metabolism in marine microorganisms: Sulfur metabolism, growth, and protein synthesis of Pseudomonas halodurans and Alteromonas luteo-violaceus during sulfate limitation  

Microsoft Academic Search

Sulfate concentration in the growth medium exerted a strong influence on the sulfur content of protein in two marine bacteria, Pseudomonas halodurans and Alteromonasluteo-violaceus, but the distribution of sulfur in major biochemical fractions was not affected. 90% of the total cellular sulfur was contained in low molecular weight organic compounds and protein; inorganic sulfate was not an important component. The

Russell L. Cuhel; Craig D. Taylor; Holger W. Jannasch

1981-01-01

315

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...

316

Determination of sulfur trioxide in engine exhaust.  

PubMed Central

Sulfur trioxide in the exhaust gas of an internal combustion engine is removed and concentrated by absorption in a solution of 80% isopropyl alcohol, which quantitatively absorbs it and inhibits the oxidation of any sulfur dioxide which may be absorbed. The absorbed sulfur trioxide (sulfuric acid) is determined by an absorption titration by using barium chloride as the titrant and thorin as the indicator. The sulfur dioxide content of the exhaust is measured continuously by means of a DuPont Model 411 ultraviolet photoanalyzer.

Arnold, D R

1975-01-01

317

Antibotulinal efficacy of sulfur dioxide in meat.  

PubMed Central

The addition of sodium metabisulfite as a source of sulfur dioxide delayed botulinal outgrowth in perishable canned comminuted pork when it was temperature abused at 27 degree C. The degree of inhibition was directly related to the level of sulfur dioxide. Levels greater than 100 microgram of sulfur dioxide per g were necessary to achieve significant inhibition when a target level of 100 botulinal spores per g was used. Sodium nitrite partially reduced the efficacy of the sulfur dioxide. Sulfur dioxide offers a new option for the control of botulinal outgrowth in cured or noncured meat and poultry products.

Tompkin, R B; Christiansen, L N; Shaparis, A B

1980-01-01

318

Effects of high salinity and constituent organic compounds on treatment of photo-processing waste by a sulfur-oxidizing bacteria\\/granular activated carbon sludge system  

Microsoft Academic Search

To achieve practical treatment of photo-processing waste (PW) using our previously proposed sulfur-oxidizing bacteria (SOB)\\/granular activated carbon (GAC) sludge system, this paper elucidates why 3- to 5-X dilution of PW was required. That is, a series of experiments were carried out to show the effects of high salinity and constituent organic compounds in PW, respectively. Both an inorganic salts system

Bin-Le Lin; Masaaki Hosomi; Akihiko Murakami

2002-01-01

319

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

PubMed Central

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.

Auernik, Kathryne S.; Kelly, Robert M.

2008-01-01

320

Bipotentiometry in Organic Redox Systems. II. Oxidation of Nonaromatics Including Sulfur Compounds.  

National Technical Information Service (NTIS)

Bipotentiometry has been found to be applicable in the oxidation with lead (IV) acetate of various polyenes and organosulfur compounds in trifluoroacetic acid. It is assumed that oxidation produces intermediates such as radical cations that are electroche...

H. W. Yurow S. Sass

1971-01-01

321

Allyl sulfur compounds and cellular detoxification system: effects and perspectives in cancer therapy  

Microsoft Academic Search

Natural organosulfur compounds (OSCs) have been shown to have chemopreventive effects and to suppress the proliferation of\\u000a tumor cells in vitro through the induction of apoptosis. The biochemical mechanisms underlying the antitumorigenic and anti-proliferative\\u000a effects of garlic-derived OSCs are not fully understood. Several modes of action of these compounds have been proposed, and\\u000a it seems likely that the rate of

S. Melino; R. Sabelli; M. Paci

2011-01-01

322

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

PubMed Central

The susceptibility of two-coordinate mercury alkyl compounds of the type XHgR (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 HgC 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 HgC 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 HgC 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.

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

2009-01-01

323

A method for measuring nitric oxide radical scavenging activity. Scavenging properties of sulfurcontaining compounds  

Microsoft Academic Search

A new method for the quantification of the nitric oxide (NO) scavenging activity of compounds in aqueous solutions is described using an amperometric NO sensor. After correction for the spontaneous degradation of NO, secondorder rate kinetics of the scavenging reaction are observe. The rate constant for hemoglobin found with this method is comparable with that found with an established spectrophotometric

Martijn F. Vriesman; Guido R. M. M. Haenen; Jos B. G. Paquay; Aalt Bast

1997-01-01

324

Method for removing sulfur oxide from waste gases and recovering elemental sulfur  

DOEpatents

A continuous catalytic fused salt extraction process is described for removing sulfur oxides from gaseous streams. The gaseous stream is contacted with a molten potassium sulfate salt mixture having a dissolved catalyst to oxidize sulfur dioxide to sulfur trioxide and molten potassium normal sulfate to solvate the sulfur trioxide to remove the sulfur trioxide from the gaseous stream. A portion of the sulfur trioxide loaded salt mixture is then dissociated to produce sulfur trioxide gas and thereby regenerate potassium normal sulfate. The evolved sulfur trioxide is reacted with hydrogen sulfide as in a Claus reactor to produce elemental sulfur. The process may be advantageously used to clean waste stack gas from industrial plants, such as copper smelters, where a supply of hydrogen sulfide is readily available.

Moore, Raymond H. (Richland, WA)

1977-01-01

325

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

Microsoft Academic Search

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

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

2010-01-01

326

Pyrolysis of Model Sulfur-Containing Compounds in Molten Salt NaAlCl4  

Microsoft Academic Search

The authors experimentally investigated pyrolysis of model vulcanized butadiene compounds with different sulphur content on the melt of NaAlCl4. The maximum yield of liquid pyrolysis products occurs at 400C, and is independent on S content. There was also observed strong desulphurization of liquid products, due to removal of S with the pyrolysis gases in the form of H2S. On the

A. Besruckov; O. Deryabina; L. Maharinsky; N. Halturinsky

1990-01-01

327

Emission of sulfur-bearing compounds from motor vehicle and aircraft engines. A report to congress  

Microsoft Academic Search

This report was generated in response to section 403(g) of The Clean Air Act as amended August, 1977. The report covers (1) a review of emission factors for HSO, SO, sulfate, HS, and carbonyl sulfide from motor vehicles, motor vehicle engines and aircraft engines; (2) a review of the known effects on health and welfare of these compounds; (3) the

Kawecki

1978-01-01

328

Sulfur Cycling in Constructed Wetlands  

Microsoft Academic Search

Constructed wetlands (CWs) have been successfully employed in both mining and domestic wastewater applications, yet the fundamental\\u000a processes responsible for treatment are poorly quantified. Sulfur is common in CW influent streams and is highly reactive,\\u000a redox-sensitive, and microbially active; therefore, it plays an important role in both desirable and deleterious processes\\u000a in CWs. In this chapter we review the major

Paul J. Sturman; Otto R. Stein; Jan Vymazal; Lenka Krpfelov

329

Titanium and Iron Oxide-Based Magnetic Photocatalysts for Oxidation of Organic Compounds and Sulfur Dioxide  

Microsoft Academic Search

New approaches to designing magnetic photocatalysts on the basis of microheterogeneous structures built according to the scheme magnetic corephotocatalytic shell were proposed. A procedure for preparing the Zn0.35Ni0.65Fe2O4\\/SiO2\\/TiO2 catalyst designed for the destructive oxidation of organic compounds, as well as the Fe3O4\\/Fe2O3\\/Fe4[Fe(CN)6]3: KCo[Co(CN)6] and Fe3O4\\/Fe2O3\\/polyaniline catalysts designed for the photo-oxidation of SO2, was considered. It was shown that the reduction

D. G. Shchukin; E. A. Ustinovich; D. V. Sviridov; A. I. Kulak

2004-01-01

330

Metal-sulfur type cell having improved positive electrode  

DOEpatents

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.

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

331

Metal-sulfur type cell having improved positive electrode  

DOEpatents

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.

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

1988-03-31

332

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

PubMed

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

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

2012-02-27

333

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

PubMed

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

Starkenmann, Christian; Niclass, Yvan

2011-03-04

334

Perfluorinated oxygen- and sulfur-containing compounds as extractants for gold(III)  

Microsoft Academic Search

A series of highly fluorinated compounds of the type {CF3(CF2)5CH2CH2}3P=O, [{CF3(CF2)5CH2CH2}2P(E)CH2CH2P(E){CH2CH2(CF2)5CF3}] and {CF3(CF2)5CH2CH2}2C=E (E = O or S) have been examined for their ability to extract gold(III) from aqueous solutions. The phosphine oxides have\\u000a been studied under liquidliquid extraction conditions from water into perfluorohexane and found to give poor distribution\\u000a ratios. The bidentate phosphine oxide, ketone and thioketone were studied

Julia Baker; Robert J. Baker; Carola Schulzke

335

In vivo nitrogen dioxide exposure depresses spleen cell in vitro mitogenic responses: effects of sulfur compounds  

SciTech Connect

The in vivo mitogenic responses to lipopolysaccharide or concanavalin A by spleen cells of mice exposed to 20 ppm nitrogen dioxide (NO/sub 2/) for 96 hr, were evaluated. (/sup 3/H)Thymidine incorporation after addition of either mitogen, was significantly lower in spleen cells from acutely NO/sub 2/-exposed mice (NO/sub 2/SC) than from control mice, although cell viability was not affected. T- and B-cell mitogenic responses were inhibited to the same extent by NO/sub 2/ exposure. NO/sub 2/SC responses were protected by the thiol compounds 2-mercaptoethanol, L-cysteine, and selenomethionine. No restoration of mitogenic response was observed after treatment with reduced glutathione. Mechanisms accounting for this in vivo NO/sub 2/ immune toxicity, are discussed in terms of oxidative injury.

Azoulay-Dupuis, E.; Gougerot-Pocidalo, M.A.; Kraus, L.; Moreau, J.

1987-02-01

336

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

PubMed

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

Guo, Juchen; Xu, Yunhua; Wang, Chunsheng

2011-09-22

337

Comparative Aspects of Sulfur Mineralization in Sediments of a Eutrophic Lake Basin  

PubMed Central

The net mineralization of organic sulfur compounds in surface sediments of Wintergreen Lake was estimated from a mass-balance budget of sulfur inputs and sediment sulfur concentrations. The net mineralization of organic sulfur inputs is <50% complete, which is consistent with the dominance of organic sulfur (>80% of total sulfur) in sediment. Although sediment sulfur is predominantly organic, sulfate reduction is the most significant process in terms of the quantities of sulfur transformed in surface sediments. Rates of sulfate reduction in these sediments average 7 mmol/m2 per day. On an annual basis, this rate is 19-fold greater than net rates of organic sulfur mineralization and 65-fold greater than sulfate ester hydrolysis.

King, Gary M.; Klug, M. J.

1982-01-01

338

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

SciTech Connect

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.

Attar, A.

1983-05-01

339

Electron capture sulfur detector: reduced sulfur species detection at the femtomole level  

SciTech Connect

The authors have developed a new technique to detect reduced sulfur compounds by fluorination with F/sub 2/ (at 200 ppm) on a heated Ag catalyst after GC separation. The excess F/sub 2/ is removed by conversion to HF by reaction with H/sub 2/ on a heated Pd catalysts. The fluorination product, presumably SF/sub 6/, is then detected in an electron capture detector (ECD). The Pd catalyst also destroys the response from halocarbons making the system sulfur specific. This ECD sulfur detector has a calculated minimum detectable level (MDL) for H/sub 2/S, OCS, CH/sub 3/SH, DMS, and CS/sub 2/ of less than 2 fmol/s for each compound, 2 orders of magnitude lower than the best FPD systems. The ratio of the detected molar response of each of these sulfur compounds to the molar response of SF/sub 6/ ranges from 2% to 20% and increases with increasing AgF/sub 2/ temperature.

Johnson, J.E.; Lovelock, J.E.

1988-04-15

340

Biotic and abiotic carbon to sulfur bond cleavage. Final report  

SciTech Connect

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.

Frost, J.W.

1994-05-01

341

Wet scavenging of sulfur compounds and other constituents during the Indian Ocean Experiment (INDOEX)  

NASA Astrophysics Data System (ADS)

Rainwater samples for chemical analysis were collected over the Indian Ocean during the Indian Ocean Experiment (INDOEX) campaign January-March 1999 on board the research vessels Ronald H. Brown and Sagar Kanya. Samples were analyzed for major ions and some trace metals. The rainwater data are interpreted in terms of transport from potential source regions in Asia using air mass trajectories covering 10 days. A comparison is also made between the rainwater data and the concentration of aerosol components measured simultaneously on the ships. The concentrations of nonsea-salt (nss)-SO42-, NO3-, NH4+, nss-K+, and nss-Ca2+ in rainwater over the Indian Ocean, while a factor of 2 to 3 lower than over the Indian continent, were still clearly influenced by pollution and soil sources in Asia. The concentration of nss-Ca2+ decreased more rapidly as the air moved southward from the continent out over the ocean, whereas the concentration of nss-SO42- became relatively more abundant. This was consistent with the observed higher acidity of the rainwater over the ocean (pH in the range 4.8 to 5.4) than over the Indian subcontinent, with NH4+ as the main cation (rather than Ca2+, as over land). Variations in the concentration of Al and Fe correlated well with those of nss-Ca2+, indicating a crustal source for these elements. The relation between Na+, Cl-, and Br- in the rainwater was close to that of seawater, implying no excess or deficit of the two halogen ions. The ratio between the concentration in rainwater and the concentration in surface air was systematically larger for aerosol components that exist in the coarse mode of sea-salt origin (Na+, Mg2+, and Cl-) than those in the fine mode (NH4+, nss-K+, and nss-SO42-), indicating that fine-mode particles are scavenged mainly by in-cloud processes whereas coarse-mode sea-salt particles are scavenged also by falling raindrops under the clouds. Nss-Ca2+ and NO3- fall in a category in between, indicating that these compounds are not as effectively removed by below-cloud scavenging as sea-salt aerosols.

Granat, L.; Norman, M.; Leck, C.; Kulshrestha, U. C.; Rodhe, H.

2002-10-01

342

Radiolysis of sulfuric acid, sulfuric acid monohydrate, and sulfuric acid tetrahydrate and its relevance to Europa  

NASA Astrophysics Data System (ADS)

We report laboratory studies on the 0.8 MeV proton irradiation of ices composed of sulfuric acid (H 2SO 4), sulfuric acid monohydrate (H 2SO 4H 2O), and sulfuric acid tetrahydrate (H 2SO 44H 2O) between 10 and 180 K. Using infrared spectroscopy, we identify the main radiation products as H 2O, SO 2, (S 2O 3) x, H 3O +, HSO4-, and SO42-. At high radiation doses, we find that H 2SO 4 molecules are destroyed completely and that H 2SO 4H 2O is formed on subsequent warming. This hydrate is significantly more stable to radiolytic destruction than pure H 2SO 4, falling to an equilibrium relative abundance of 50% of its original value on prolonged irradiation. Unlike either pure H 2SO 4 or H 2SO 4H 2O, the loss of H 2SO 44H 2O 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 SO 2 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.

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

2011-09-01

343

World petroleum-derived sulfur production  

SciTech Connect

Research efforts in new uses for sulfur, among them those of the Sulfur Development Institute of Canada, have resulted in the development of several new product markets. Petroleum and natural gas derived sulfurs are finding use as asphalt extenders in road construction throughout North America and as concrete extenders and substitutes for Portland cement in the construction industries of Mexico and the Middle East. Their use in masonry blocks is now being commercialized. Canada is the world's largest producer of commercial sulfur; 80% of it is used as a processing chemical in the form of sulfuric acid. Saudi Arabia, recently having begun to commercialize its vast resources, is constructing plants for the extraction of sulfur from natural gas and plans to export between 6 and 7 x 10/sup 5/ tons annually, much of it for fertilizer manufacture to India, Tunisia, Italy, Pakistan, Greece, Morocco, and Thailand.

Cantrell, A.

1982-08-02

344

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

Code of Federal Regulations, 2013 CFR

...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...

2013-07-01

345

Introduction to Sulfur Metabolism in Phototrophic Organisms  

Microsoft Academic Search

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

Christiane Dahl; Rdiger Hell; Thomas Leustek; David Knaff

346

HYDROCARBON AND SULFUR SENSORS FOR SOFC SYSTEMS  

SciTech Connect

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.

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

2003-11-01

347

Effects of elemental sulfur during programmed pyrolysis  

Microsoft Academic Search

The effects of elemental sulfur during programmed pyrolysis (Rock-Eval method) of Eocene Green River shale and common rock matrix minerals were assessed experimentally. Mixtures of elemental sulfur and Green River shale with calcium carbonate, silicon dioxide, and calcium sulfate were analyzed. With weight-fraction Green River shale held at a near-constant value, geologically realistic contents of elemental sulfur result in substantial

R. Sassen; E. W. Chinn

1989-01-01

348

Nutritional studies with Pseudomonas aeruginosa grown on inorganic sulfur sources.  

PubMed Central

Pseudomonas aeruginosa was grown on a succinate-basal salts medium supplemented with various inorganic sulfur compounds as its sole source of sulfur. The organism was able to grow on the sodium salts of sulfide, thiosulfate, tetrathionate, dithionite, metabisulfite, sulfite, or sulfate, but not on those of dithionate. Analyses of the culture media after 24 h of growth indicated accumulation of sulfate from each inorganic sulfur source except sulfate. Manometric studies with resting cells obtained by growth on each of these sulfur sources yielded net oxygen uptake for all substrates except sulfite and dithionate. Similar results were obtained with extracts from these cells by spectrophotometric techniques. Thiosulfate oxidase activity appeared to be induced by growth on sulfide, thiosulfate, or tetrathionate, with little or no activity observed when cells were grown on inorganic sulfur sources of higher oxidative states. Metabisulfite oxidase appeared to be associated with growth on all inorganic sulfur compounds. Rhodanese activity appeared to be constitutively present, and its activity, observed only in soluble fraction, seemed independent of the growth medium employed. Thiosulfate and tetrathionate oxidase activities were studied in greater detail than some of the other sulfur oxidases, and both were found to be distributed between particulate and soluble fractions.

Schook, L B; Berk, R S

1978-01-01

349

Limestone Corrosion by Neutrophilic Sulfur-Oxidizing Bacteria: A Coupled Microbe-Mineral System  

Microsoft Academic Search

Subsurface karst aquifers receiving sulfidic water can host complex chemolithotrophic microbial communities that are capable of dissolving limestone, forming new karstic habitat. Neutrophilic sulfur-oxidizing bacteria use reduced sulfur compounds as energy rich substrate, potentially producing sulfuric acid as a geochemically reactive byproduct. The physicochemical relationship between a biofilm forming on a limestone surface and the extent of microbial influence on

Elspeth S. Steinhauer; Christopher R. Omelon; Philip C. Bennett

2010-01-01

350

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

Microsoft Academic Search

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

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

2009-01-01

351

Genetic and Proteomic Studies of Sulfur Oxidation in Chlorobium tepidum (syn. Chlorobaculum tepidum)  

Microsoft Academic Search

The oxidation of reduced sulfur compounds is perhaps the most poorly understood physiological process carried out by the green\\u000a sulfur bacteria (the Chlorobiaceae). My laboratory is testing models of sulfur oxidation pathways in the model system Chlorobium tepidum (ATCC 49652 syn. Chlorobaculum tepidum (Imhoff, 2003) ) by the creation and analysis of mutant strains lacking specific gene products. The availability

Leong-Keat Chan; Rachael Morgan-Kiss; Thomas E. Hanson

352

Taxonomy and Ecology of the Sulfur Bacteria.  

National Technical Information Service (NTIS)

Contents: Culture; Occurrences in nature (General, Thiorhodaceae, Chlorobacteriaceae, Thiobacteriaceae, Chlamydobacteriaceae, Beggiatoaceae, Thiodendron, Achromatiaceae); Characteristics of waters in which sulfur bacteria were found (temperature, light, p...

J. B. Lackey E. W. Lackey G. B. Morgan E. B. Phelps

1965-01-01

353

Charles H. Winston and Confederate Sulfuric Acid  

NASA Astrophysics Data System (ADS)

Sulfuric acid turned out to be one of the critical chemicals made in the South during the Civil War. It was necessary for the manufacture of mercury fulminate which was used in the production of percussion caps and sulfuric acid was used in the Daniells cell to produce electricity. Charles H. Winston, president of the Richmond Female Institute and later professor at the University of Richmond (VA) was instrumental in the establishment of a plant to manufacture sulfuric acid in Charlotte, North Carolina. His patent and method of manufacture plus the uses of sulfuric acid during the Civil War are discussed.

Reithmiller, Steven

1995-07-01

354

Mobility of sulfur in thermally altered meteorites  

NASA Astrophysics Data System (ADS)

Sulfur and volatile trace element (bismuth, cadmium, and thallium) mobility were studied in Allende (CV3) and Leedey (L6) chondrite samples heated for 1 to 168 hours, at 100 C increments, from 400 to 1000 C in a low pressure environment of hydrogen and oxygen. A vacuum system was constructed to heat samples in an open and closed environment. Three trace elements were determined by direct analysis of solids using electrothermal atomic absorption spectroscopy. Sulfur was determined by either iodometric titration or infrared absorption of sulfur dioxide expelled during inductive heating of samples in an oxygen environment. The sulfur gases released during the heating experiments were also analyzed by gas chromatography to better understand the mechanism of sulfur mobility. Sulfur is very mobile in a low pressure oxygen environment (10 exp -8 power atm) at 650 C. Sulfur is also mobilized in a low-pressure hydrogen environment (10 exp -5 power atm) at 650 C, but to a lesser extent. Ordinary chondrites have a constant sulfur content. They are depleted in sulfur by a factor of two compared to CI chondrites. The results are compared to earlier heating experiments completed by the Purdue group, J. Cripe and J. W. Larimer (1976) and E. K. Gibson, Jr. (1976). The loss of volatile trace elements from ordinary chondrites by simple open system metamorphism is not supported by the results obtained.

Primus, Thomas Michael

355

Improved sulfur removal processes evaluated for IGCC  

SciTech Connect

An inherent advantage of Integrated Coal Gasification Combined Cycle (IGCC) electric power generation is the ability to easily remove and recover sulfur. During the last several years, a number of new, improved sulfur removal and recovery processes have been commercialized. An assessment is given of alternative sulfur removal processes for IGCC based on the Texaco coal gasifier. The Selexol acid gas removal system, Claus sulfur recovery, and SCOT tail gas treating are currently used in Texaco-based IGCC. Other processes considered are: Purisol, Sulfinol-M, Selefning, 50% MDEA, Sulften, and LO-CAT. 2 tables.

Not Available

1986-12-01

356

Options for small-scale sulfur recovery  

SciTech Connect

With the issuance by the Alberta Energy Resources Conservation Board and Alberta Environment of their report entitled Sulphur Recovery Guidelines for Sour Gas Plants in Alberta in August of 1988, the requirement in Alberta to recover sulfur was broadened to a sulfur content of 1 ton/D or greater in the inlet gas to a new sour-gas treating plant. This paper reviews the processes in use for recovering sulfur from sour-natural-gas streams that have a total sulfur content of 5 ton/D or less. These processes are the modified Claus process, the recycle Selectox process, and the reduction/oxidation processes LO-CAT and SulFerox. While the modified Claus process is used in large sulfur-recovery plants, the other processes may be more economical for sulfur recovery on a small scale. A description of the sour-gas treating and sulfur-recovery processes is given, and a comparison of estimated capital and operating costs for typical sour-gas streams is provided. All of the above processes are in operation in North America. Operating experiences with these processes in Alberta are discussed. The quality of the end-product sulfur varies among these processes, and the options for sulfur disposal are reviewed.

Royan, T. [Tartan Engineering Corp. Ltd. (Canada); Wichert, E. [Gascan Resources Ltd., Calgary, Alberta (Canada)

1997-11-01

357

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

Microsoft Academic Search

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 400600C were found to be optimal for producing effective mercury uptake sorbents. The increased amount of sulfur deposited during the

Wenguo Feng; Eric Borguet; Radisav D. Vidic

2006-01-01

358

Prediction Model of Sulfur Deposition in the High Sulfur Gas Well Bore  

Microsoft Academic Search

Sulfur deposition in the well bore not only jams the equipment and pipeline, but also gets heavy corrosion of down-holes\\u000a pipe string and rig on ground. The accurate prediction of sulfur deposition in the well bore is very important. Because sulfur\\u000a solubility is a function of temperature and pressure in the high sulfur gas well bore, this paper addressed solubility

Chun-bi Xu; Jiong Wang; Shun-peng Zeng

359

Exchange of sulfur pollution between Bulgaria and Greece.  

PubMed

The EMAP model (Eulerian Model for Air Pollution) is applied for calculating the sulfur concentration and deposition fields for 1995 as based upon Bulgarian and Greek sources. The country-to-country budgets show that about 4% of the sulfur oxides emitted by Bulgaria are deposited over Greek territory, estimated at 28 kt S. Only 2% of sulfur compounds emitted by Greece are deposited over Bulgaria, estimated at 6.2 kt S for 1995. This data is in agreement with EMEP/MSC-W estimates and provides more details concerning time and space. The results can be used in decision-making, negotiating and the development of contamination strategies. PMID:12391807

Syrakov, Dimiter; Prodanova, Maria; Ganev, Kostadin; Zerefos, Christos; Vasaras, Alexandros

2002-01-01

360

Method for the conversion of calcium sulfoxy compounds into calcium carbonate compounds in sulfur oxide treatment processes  

SciTech Connect

A method for converting calcium sulfoxy compounds selected from the group consisting of casox and ca(Hsox)2 and their hydrates wherein X is 3 or 4 into calcium carbonate, the method consisting essentially of; converting the ca(Hsox)2 compounds into casox compounds by reacting the ca(Hsox)2 compounds with calcium carbonate in the presence of water, thereafter reacting the casox compounds with ammonia and carbon dioxide in the presence of water to produce nh4(Hsox) wherein X is 3 or 4 and calcium carbonate, thereafter separating the nh4(Hsox) and calcium carbonate and reacting the nh4(Hsox) with carbon to produce ammonia, hydrogen sulfide and carbon oxides.

Clark, W.E.

1980-05-06

361

Development of the Hybrid Sulfur Thermochemical Cycle  

SciTech Connect

The production of hydrogen via the thermochemical splitting of water is being considered as a primary means for utilizing the heat from advanced nuclear reactors to provide fuel for a hydrogen economy. The Hybrid Sulfur (HyS) Process is one of the baseline candidates identified by the U.S. Department of Energy [1] for this purpose. The HyS Process is a two-step hybrid thermochemical cycle that only involves sulfur, oxygen and hydrogen compounds. Recent work has resulted in an improved process design with a calculated overall thermal efficiency (nuclear heat to hydrogen, higher heating value basis) approaching 50%. Economic analyses indicate that a nuclear hydrogen plant employing the HyS Process in conjunction with an advanced gas-cooled nuclear reactor system can produce hydrogen at competitive prices. Experimental work has begun on the sulfur dioxide depolarized electrolyzer, the major developmental component in the cycle. Proof-of-concept tests have established proton-exchange-membrane cells (a state-of-the-art technology) as a viable approach for conducting this reaction. This is expected to lead to more efficient and economical cell designs than were previously available. Considerable development and scale-up issues remain to be resolved, but the development of a viable commercial-scale HyS Process should be feasible in time to meet the commercialization schedule for Generation IV gas-cooled nuclear reactors.

Summers, William A.; Steimke, John L

2005-09-23

362

Sulfur isotopic variations in low-sulfur coals from the Rocky Mountain region  

Microsoft Academic Search

The isotopic composition of organic sulfur and disseminated and massive pyrite has been determined in vertical sections from eight low-sulfur coals (Paleocene and Cretaceous in age) in four coal fields of Wyoming and Colorado. The 34 S values of organic sulfur from five sites in the Anderson-Wyodak coal (Paleocene) of the eastern Powder River Basin, Wyoming, are more negative than

Keith C. Hackley; Thomas F. Anderson

1986-01-01

363

Phase transformations and the spectral reflectance of solid sulfur - Can metastable sulfur allotropes exist on Io?  

Microsoft Academic Search

Laboratory investigations have been conducted on the effects of variations in sulfur sample histories on their solid-state transformation rate and the corresponding spectral variation of freshly frozen sulfur. The temporal variations in question may be due to differences in the amount and type of metastable allotropes present in the sulfur after solidification, as well as to the physics of the

J. I. Moses; D. B. Nash

1991-01-01

364

High pressure sulfuric acid decomposition experiments for the sulfur-iodine thermochemical cycle  

Microsoft Academic Search

A series of three pressurized sulfuric acid decomposition tests were performed to (1) obtain data on the fraction of sulfuric acid catalytically converted to sulfur dioxide, oxygen, and water as a function of temperature and pressure, (2) demonstrate real-time measurements of acid conversion for use as process control, (3) obtain multiple measurements of conversion as a function of temperature within

Carlos E Velasquez; Andrew R. Reay; James C. Andazola; Gerald E. Naranjo; Fred Gelbard

2005-01-01

365

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.  

PubMed

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 (CH(4)), hydrogen sulfide (H(2)S), ammonia (NH(3)), and carbon dioxide (CO(2)). 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 H(2)S 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. PMID:21063908

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

2010-11-10

366

Effects of rehydration nutrients on H2S metabolism and formation of volatile sulfur compounds by the wine yeast VL3  

PubMed Central

In winemaking, nutrient supplementation is a common practice for optimising fermentation and producing quality wine. Nutritionally suboptimal grape juices are often enriched with nutrients in order to manipulate the production of yeast aroma compounds. Nutrients are also added to active dry yeast (ADY) rehydration media to enhance subsequent fermentation performance. In this study we demonstrate that nutrient supplementation at rehydration also has a significant effect on the formation of volatile sulfur compounds during wine fermentations. The concentration of the 'fruity' aroma compounds, the polyfunctional thiols 3-mercaptohexan-1-ol (3MH) and 3-mercaptohexyl acetate (3MHA), was increased while the concentration of the 'rotten egg' aroma compound, hydrogen sulfide (H2S), was decreased. Nutrient supplementation of the rehydration media also changed the kinetics of H2S production during fermentation by advancing onset of H2S production. Microarray analysis revealed that this was not due to expression changes within the sulfate assimilation pathway, which is known to be a major contributor to H2S production. To gain insight into possible mechanisms responsible for this effect, a component of the rehydration nutrient mix, the tri-peptide glutathione (GSH) was added at rehydration and studied for its subsequent effects on H2S formation. GSH was found to be taken up during rehydration and to act as a source for H2S during the following fermentation. These findings represent a potential approach for managing sulfur aroma production through the use of rehydration nutrients.

2011-01-01

367

Effects of rehydration nutrients on H2S metabolism and formation of volatile sulfur compounds by the wine yeast VL3.  

PubMed

In winemaking, nutrient supplementation is a common practice for optimising fermentation and producing quality wine. Nutritionally suboptimal grape juices are often enriched with nutrients in order to manipulate the production of yeast aroma compounds. Nutrients are also added to active dry yeast (ADY) rehydration media to enhance subsequent fermentation performance. In this study we demonstrate that nutrient supplementation at rehydration also has a significant effect on the formation of volatile sulfur compounds during wine fermentations. The concentration of the 'fruity' aroma compounds, the polyfunctional thiols 3-mercaptohexan-1-ol (3MH) and 3-mercaptohexyl acetate (3MHA), was increased while the concentration of the 'rotten egg' aroma compound, hydrogen sulfide (H2S), was decreased. Nutrient supplementation of the rehydration media also changed the kinetics of H2S production during fermentation by advancing onset of H2S production. Microarray analysis revealed that this was not due to expression changes within the sulfate assimilation pathway, which is known to be a major contributor to H2S production. To gain insight into possible mechanisms responsible for this effect, a component of the rehydration nutrient mix, the tri-peptide glutathione (GSH) was added at rehydration and studied for its subsequent effects on H2S formation. GSH was found to be taken up during rehydration and to act as a source for H2S during the following fermentation. These findings represent a potential approach for managing sulfur aroma production through the use of rehydration nutrients. PMID:22044590

Winter, Gal; Henschke, Paul A; Higgins, Vincent J; Ugliano, Maurizio; Curtin, Chris D

2011-11-02

368

Development of instrumental methods of analysis of sulfur compounds in coal process streams. Eleventh quarterly technical progress report, April-June 1980  

Microsoft Academic Search

Full implementation of an algorithm for calculating thermodynamic estimates of sulfur moiety concentrations is reported. The scope of the algorithm is unrestricted, including mononuclear and polynuclear sulfur species. Implementation is achieved through the use of substantiated numerical approximation. In Voltammetric Method Development, equations describing the analytic geometry of differential pulse voltammograms are reviewed critically. Work on appropriate refinements has been

1980-01-01

369

Enhanced sulfur removal from fuels  

SciTech Connect

This patent describes a process for hydrotreating a petroleum distillate feedstock in a plurality of hydrotreating zones. It comprises splitting the feedstock by fractionation into at least two different boiling point fractions, including a first distillate stream relatively depleted in sulfur and a second distillate stream relatively concentrated in sulfur, wherein the first distillate stream boils in the range of 350{degrees} to 575{degrees} F and the second distillate stream boils in the range of 575{degrees} to 700{degrees} F; hydrotreating in a first hydrotreating zone the first distillate stream in admixture with an excess of hydrogen to obtain a first effluent; and hydrotreating in a second hydrotreating zone, the second distillate stream in admixture with an excess of hydrogen to obtain a second effluent; wherein the first hydrotreating zone is at a total pressure of 100 wherein the first hydrotreating zone is at a total pressure of 100 to 250 psia and the second hydrotreating zone is at a total pressure of 100 to 800 psia and the ratio of total pressure in the first hydrotreating zone to the total pressure in the second hydrotreating zone is in the range of about 1:2 to 1:8 and whereby a greater hydrogen consumption per barrel occurs in the second hydrotreating zone than in the first hydrotreating zone.

Kingswood, S.L.; Markley, G.E.

1991-02-05

370

Contribution of Gulf Area natural sulfur to the North American sulfur budget  

SciTech Connect

To evaluate the contribution of natural sulfur compounds from the Gulf of Mexico to the overall North American sulfur budget two series of air sampling flights were performed over the gulf area. Total aerosol mass load and sulfate concentration data indicate, in agreement with our previous findings on gas-phase products, that these observations can be divided into two categories. One group of measurements was taken under offshore airflow and the other under onshore flow conditions. From the measurements performed under clean (onshore) flow, average inside boundary layer SO/sub 4//sup 2 -/ concentrations were evaluated. Using these data, together with our previously reported dimethyl sulfide levels, a simple model was developed to estimate the sulfur flux transported northward from the gulf area. Upper and lower limits of this contribution are estimated at 0.25 and 0.04 Tg (S) year/sup -1/, respectively. Although this quantity is relatively low compared with the national US anthropogenic emission, it has significance for the global sulfur cycle, and it can cause a significant acidification of cloud water. 24 references, 5 figures, 3 tables.

Luria, M.; Van Valin, C.C.; Wellman, D.L.; Pueschel, R.F.

1986-01-01

371

Occurrence and identification of series of organic sulfur compounds in oils and sediment extracts. I. A study of Rozel Point Oil (USA)  

SciTech Connect

A number of novel series of organic sulfur compounds (OSC) have been identified in several oils and sediment extracts including Rozel Point Oil (Bos Elder County, Utah, U.S.A.; Miocene). This oil contains these series in abundance, and the OSC were therefore studied in detail. The aromatic fraction was fractionated using column chromatography, and the fractions obtained were analyzed by GC with simultaneous flame ionization and flame photometric detection (PFD) and by Gas Chromatography/Ma (GC-MS). Series of isoprenoid thiophenes, isoprenoid thiolanes, isoprenoid bithiophenes, isoprenoid thienylthiolanes, isoprenoid benzothiophenes, thiophene and thiolane steranes, 2,5-di-n-alkylthiolanes, 2,6-di-n-alkylthianes and 2,4-di-n-alkylbenzo(b)thiophenes have been identified. The identifications were based on chromatographic and mass spectral data, response on the FPD, carbon skeleton determination by desulfurization and in some cases on mass spectral data from, and coinjections with, synthetic compounds. Together, almost 1000 OSC have been identified in the aromatic fraction of this oil. Because the carbon skeletons of the OSC identified have the same structures as the well know hydrocarbons from geological materials (isoprenoid hydrocarbons, steranes, n-alkanes) these compounds are thought to be products of sulfur incorporation reactions into specific precursors.

Damste, J.S.S.; De Leeuw, J.W.; Dalen, A.C.K.; De Zeeuw, M.A.; Lange, F.; Rijstra, W.I.C.; Schenck, P.A.

1987-09-01

372

Sulfur oxide adsorbents and emissions control  

DOEpatents

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.

Li, Liyu (Richland, WA); King, David L. (Richland, WA)

2006-12-26

373

Fate of excess sulfur in higher plants  

SciTech Connect

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 excess sulfur taken up is, however, prevented by a series of metabolic processes. Storage of excess sulfur in a metabolically inactive compartment, i.e. the vacuole, appears to occur in most plants. The finding of a storage of glutathione is several investigations suggests that with increasing accumulation of sulfate its reduction also increases. Under these conditions the cysteine concentration in different compartments of the cell may still be maintained at a low level by the incorporation of the excess cysteine synthesized into glutathione. This peptide appears to be the storage form of reduced sulfur in higher plants. 167 references, 2 figures.

Rennenberg, H.

1984-01-01

374

CALCIUM AND SULFUR LOCATION IN HUMAN NAIL  

Microsoft Academic Search

Analytical electron microscopy was performed in order to elucidate the importance of calcium and sulfur to the hardness of nails. The free surfaces adsorb a considerable quantity of calcium from the environment. It is suggested that such adsorption occurs due to ion exchange. This concept is supported by the fact that the distribution of sulfur does not vary over the

B. Forslind; R. Wroblewski; B. A. Afzelius

1976-01-01

375

Method for measuring gaseous sulfur dioxide  

Microsoft Academic Search

A method is described for measuring sulfur dioxide or sulfur trioxide in an oxygen-containing gas comprising: contacting the gas with a solid electrolyte comprising lithium sulfate and silver sulfate, the electrolyte being in electrical contact with a solid reference electrode comprising lithium sulfate, silver sulfate and silver in intimate admixture; and measuring the electrical potential between the electrolyte and the

Q. G. Liu; W. L. Worrell

1986-01-01

376

Biogenic sulfur emissions in the SURE region  

Microsoft Academic Search

The objective of this study was to estimate the magnitude of biogenic sulfur emissions from the northeastern United States - defined as the EPRI Sulfate Regional Experiment (SURE) study area. Initial laboratory efforts developed and validated a portable sulfur sampling system and a sensitive, gas chromatographic analytical detection system. Twenty-one separate sites were visited in 1977 to obtain a representative

D. F. Adams; S. O. Farwell; E. Robinson; M. R. Pack

1980-01-01

377

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...

378

Options for Small-Scale Sulfur Recovery  

Microsoft Academic Search

With the issuance by the Alberta Energy Resources Conservation Board and Alberta Environment of their report entitled Sulphur Recovery Guidelines for Sour Gas Plants in Alberta in August of 1988, the requirement in Alberta to recover sulfur was broadened to a sulfur content of 1 ton\\/D or greater in the inlet gas to a new sour-gas treating plant. This paper

Tom Royan; Edward Wichert

1997-01-01

379

Sulfuric Acid and Water: Paradoxes of Dilution  

ERIC Educational Resources Information Center

|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

Leenson, I. A.

2004-01-01

380

Oxidation decomposition of nitrogen-sulfur oxides  

SciTech Connect

The oxidative decomposition of nitrogen-sulfur oxides, formed by the reaction of nitrite ion and hydrogen sulfite ion in aqueous solution, has been investigated. The oxidants used in this study included hydrogen peroxide, nitrogen dioxide, and ozone. There was a wide range of susceptibility to oxidation among the compounds studied. Ozone was a better oxidant than nitrogen dioxide and hydrogen peroxide under the conditions used. The rate expression for the reaction of hydrogen peroxide with hydroxylamine was found to be -d[H[sub 2]O[sub 2

Littlejohn, D.; Chang, S.G. (Lawrence Berkeley Lab., CA (United States). Energy Environment Division)

1994-03-01

381

Sulfur metabolism in the extreme acidophile acidithiobacillus caldus.  

PubMed

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

Mangold, Stefanie; Valds, Jorge; Holmes, David S; Dopson, Mark

2011-02-10

382

Drug Targets in Mycobacterial Sulfur Metabolism  

PubMed Central

The identification of new antibacterial targets is urgently needed to address multidrug resistant and latent tuberculosis infection. Sulfur metabolic pathways are essential for survival and the expression of virulence in many pathogenic bacteria, including Mycobacterium tuberculosis. In addition, microbial sulfur metabolic pathways are largely absent in humans and therefore, represent unique targets for therapeutic intervention. In this review, we summarize our current understanding of the enzymes associated with the production of sulfated and reduced sulfur-containing metabolites in Mycobacteria. Small molecule inhibitors of these catalysts represent valuable chemical tools that can be used to investigate the role of sulfur metabolism throughout the Mycobacterial lifecycle and may also represent new leads for drug development. In this light, we also summarize recent progress in the development of inhibitors of sulfur metabolism enzymes.

Bhave, Devayani P.; Muse, Wilson B.; Carroll, Kate S.

2011-01-01

383

Assessment of sulfur removal processes for advanced fuel cell systems  

SciTech Connect

This study consisted of a technical evaluation and economic comparison of sulfur removal processes for integration into a coal gasification-molten carbonate (CGMC) fuel cell power plant. Initially, the performance characteristics of potential sulfur removal processes were evaluated and screened for conformance to the conditions and requirements expected in commercial CGMC power plants. Four of these processes, the Selexol process, the Benfield process, the Sulfinol process, and the Rectisol process, were selected for detailed technical and economic comparison. The process designs were based on a consistent set of technical criteria for a grass roots facility with a capacity of 10,000 tons per day of Illinois No. 6 coal. Two raw gas compositions, based on oxygen-blown and air-blown Texaco gasification, were used. The bulk of the sulfur was removed in the sulfur removal unit, leaving a small amount of sulfur compounds in the gas (1 ppMv or 25 ppMv). The remaining sulfur compounds were removed by reaction with zinc oxide in the sulfur polishing unit. The impact of COS hydrolysis pretreatment on sulfur removal was evaluated. Comprehensive capital and O and M cost estimates for each of the process schemes were developed for the essentially complete removal of sulfur compounds. The impact on the overall plant performance was also determined. The total capital requirement for sulfur removal schemes ranged from $59.4/kW to $84.8/kW for the oxygen-blown cases and from $89.5/kW to $133/kW for the air-blown cases. The O and M costs for sulfur removal for 70% plant capacity factor ranged from 0.82 mills/kWh to 2.76 mills/kWh for the oxygen-blown cases and from 1.77 mills/kWh to 4.88 mills/kWh for the air-blown cases. The Selexol process benefitted the most from the addition of COS hydrolysis pretreatment.

Lorton, G.A.

1980-01-01

384

Using remotely sensed information to interpret the distribution of some volatile organic sulfur compounds in the upper ocean along an Atlantic meridional transect (AMT)  

NASA Astrophysics Data System (ADS)

Volatile organic sulfur compounds from an Atlantic Meridional Transect of the RRS James Clark Ros are presented together with optical data and upper ocean chlorophyl data. The latitudinal distribution of DMS and CH3SH is consistent with a biological source with low values in oligotrophic areas and high values in coastal regions. The DMS/CH3SH ratio shows systematic variation between oligotrophic and coastal areas and seems to correlate inversely with absorbance and fluorescence of colored dissolved organic matter. The latitudinal distribution of COS and CS2 conform with existing models based on known sources and sinks of these compounds. A system of photochemical provinces is developed for these compounds based on a previously published scheme. An estimate of the global distribution of these provinces is made based on data archives and remotely sensed data.

Kettle, A. J.; Rhee, T. S.; von Hobe, Marc; Andreae, M. O.

2000-12-01

385

Desulfurization of HS containing gas streams with production of elemental sulfur  

Microsoft Academic Search

A process is disclosed for desulfurization of gas streams by which reduced sulfur compound, such as HS, is reacted with solid sulfur removal metal oxide compound which is an oxide of chromium, combination of zinc and chromium, combination of zinc and aluminum and mixtures thereof at about 400 to 1600°F producing sulfided sulfur removal compound followed by regeneration of the

G. L. Anderson; F. O. Berry; H. A. Borders

1982-01-01

386

Exposure to liquid sulfur mustard.  

PubMed

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 and symptoms. Exposure can cause burns, conjunctivitis, pneumonia, and death. We describe 3 workers exposed to mustard at a chemical weapon storage facility. This article reports the first case of an exposure to mustard at a storage facility, as well as the first documented incident occurring in the United States. All physicians who manage patients in an acute care setting should be aware of the presentation and emergency treatments involving patients contaminated with mustard. PMID:11385337

Davis, K G; Aspera, G

2001-06-01

387

Process for preparing a sulfurized molybdenum-containing composition and lubricating oil containing said composition  

SciTech Connect

Antioxidant additives for lubricating oil are prepared by combining a polar promoter, ammonium tetrathiomolybdate, and a basic nitrogen compound complex to form a sulfur- and molybdenumcontaining composition.

Devries, L.; King, J.M.

1981-08-11

388

Sulfur K-edge XANES spectroscopy as a tool for understanding sulfur chemical state in anaerobic granular sludge  

NASA Astrophysics Data System (ADS)

Sulfur is an essential biological element, yet its biochemistry in anaerobic biofilm is poorly understood because there are few tools for studying this element in biological systems. X-ray absorption spectroscopy provides a unique approach to determining the chemical speciation of sulfur in intact biological samples. When treating sulfate containing wastewaters in full scale up-flow anaerobic sludge bed bioreactors, microbial activity forms biofilms, consisting of a complex mixture of cells and associated extracellular substances as well as undefined inorganic precipitates. In addition to the anaerobic sludges, a large variety of model compounds of S (esp. sulfides) were investigated to find consistencies in the XANES that were used to model each "valence state" of S. The results confirmed that attributing a specific valence to most sulfides is impossible as we measured a continuum of edge shifts from sulfur "-2" to "-1", depending on the electronic structure of S in the probed sulfides. In the sludges, various sulfur hot spots were probed for speciation, despite photo-reduction was sometimes a problem. First, we index the main features of complex K-edge XANES spectra for S2--type units and sulfate units. Organic sulfur compounds were also shown to contribute significantly to the sulfur species present in some anaerobic granular sludge.

van Hullebusch, E.; Rossano, S.; Farges, F.; Lenz, M.; Labanowski, J.; Lagarde, P.; Flank, A.-M.; Lens, P.

2009-11-01

389

Solvent-refined-coal (SRC) process. Determination of trace hydrocarbon, sulfur, and nitrogen compounds in SRC-II process development Unit P-99 gas streams. [Impure hydrogen in recycle gas and low pressure gas processing  

Microsoft Academic Search

A knowledge of the identity and concentration of trace hydrocarbon, sulfur, and nitrogen compounds in the various gas streams of the SRC-II Coal Liquefaction Process is needed in order to design the recycle gas purification and low pressure gas processing systems in large-scale plants. This report discusses the results of an experimental study to identify and quantify trace compounds in

J. A. Gray; R. D. Galli; J. H. McCracken

1982-01-01

390

Combined chemical and microbiological removal of organic sulfur from coal. Technical report, September 1, 1990--August 31, 1991  

SciTech Connect

The objective of this work is to investigate techniques for chemically converting the sulfur containing organic compounds in coal to compounds that can be treated microbiologically to remove the organically bound sulfur. The goal is to achieve an economically feasible mild chemical oxidation of the organic sulfur in a representative Illinois Basin coal by converting the sulfur to sulfoxides and sulfones; the carbon sulfur bond in the sulfoxides and sulfones would then be broken microbiologically and the sulfur removed from the coal as sulfate.

Raphaelian, L.A.

1991-12-31

391

Sulfur and olefin management in the gasoline  

SciTech Connect

As transportation fuel composition is fine-tuned, sulfur and olefin concentration in the gasoline will come under increased scrutiny. This paper presents various options to limit sulfur and olefins with special emphasis on FCC Gasoline Desulfurization and C{sub 5} Skeletal Isomerization. Hydrodesulfurization of the C{sub 6} + FCC gasoline and processing of the FCC C{sub 5} cut in a Tame/Skeletal Isomerization complex is shown to meet the most stringent olefin and sulfur specifications while substantially reducing RVP and increasing refinery based oxygenates production.

Nocca, J.L.; Gialella, R.M. [IFP Enterprises, Inc., Houston, TX (United States); Cosyns, J.; Burzynski, J.P. [IFP, Rueil Malmaison (France)

1995-09-01

392

Sulfuric acid/hydrogen peroxide rinsing study  

SciTech Connect

Sulfuric acid hydrogen peroxide mixtures (SPM) are commonly used in the semiconductor industry to remove organic contaminants from wafer surfaces. This viscous solution is very difficult to rinse off water surfaces. Various rinsing conditions were tested and the resulting residual acid left on the water surface was measured. Particle growth resulting from incomplete rinse is correlated with the amount of sulfur on the wafer surface measured by Time of Flight Secondary Ion Mass Spectroscopy (TOF-SIMS). The amount of sulfur on the wafer structure after the rinse step is strongly affected by the wafer film type and contact angle prior to the SPM clean.

Clews, P.J.; Nelson, G.C.; Matlock, C.A. [and others

1995-12-01

393

X-ray absorption spectroscopy of bacterial sulfur globules  

SciTech Connect

Sulfur K-edge X-ray absorption spectroscopy is a powerful in situ probe of sulfur biochemistry in intact cells and tissues. Under favorable circumstances the technique can provide quantitative information on the chemical identify of the sulfur species that are present in a sample. Prange et al. have recently reported an X-ray absorption spectroscopic study of bacterial sulfur storage globules. Unfortunately there are substantial problems with the experimental technique employed that, they contend, lead to completely erroneous conclusions. In the more recent of their two papers Prange et al. employed a curve-fitting method similar to that used by us (for more than 10 years). In essence, the method employs simply fitting a linear combination of the spectra of standard compounds to that of the unknown, in this case cultures of bacterial cells. This type of analysis can provide quantitative estimates of the individual sulfur types in the sample, but is critically dependent upon the choice of reference spectra. Prange et al. deduce substantial differences between the chemical forms of sulfur stored in the globules of different organisms; they conclude that the globules of Beggiatoa alba and Thiomargarita namibiensis contain cyclo-octasulfur (S{sub 8}), while those of other organisms contain polythionates (Acidithiobacillus ferrooxidans) and polymeric sulfur (e.g. Allochromatium vinosum). This is in contradiction with an earlier study, in which they found that sulfur in all globule species examined resembled that expected for various sized spherical particles of S{sub 8}. The discrepancy is due to an experimental artefact in the work of Prange et al. arising from their choice of transmittance detection, which is also discussed.

George, Graham N.

2002-08-01

394

Microphysical simulations of sulfur burdens from stratospheric sulfur geoengineering  

NASA Astrophysics Data System (ADS)

Recent microphysical studies suggest that geoengineering by continuous stratospheric injection of SO2 gas may be limited by the growth of the aerosols. We study the efficacy of SO2, H2SO4 and aerosol injections on aerosol mass and optical depth using a three-dimensional general circulation model with sulfur chemistry and sectional aerosol microphysics (WACCM/CARMA). We find increasing injection rates of SO2 in a narrow band around the equator to have limited efficacy while broadening the injecting zone as well as injecting particles instead of SO2 gas increases the sulfate burden for a given injection rate, in agreement with previous work. We find that injecting H2SO4 gas instead of SO2 does not discernibly alter sulfate size or mass, in contrast with a previous study using a plume model with a microphysical model. However, the physics and chemistry in aircraft plumes, which are smaller than climate model grid cells, need to be more carefully considered. We also find significant perturbations to tropospheric aerosol for all injections studied, particularly in the upper troposphere and near the poles, where sulfate burden increases by up to 100 times. This enhanced burden could have implications for tropospheric radiative forcing and chemistry. These results highlight the need to mitigate greenhouse gas emissions rather than attempt to cool the planet through geoengineering, and to further study geoengineering before it can be seriously considered as a climate intervention option.

English, J. M.; Toon, O. B.; Mills, M. J.

2012-05-01

395

Amylopectin wrapped graphene oxide/sulfur for improved cyclability of lithium-sulfur battery.  

PubMed

An amylopectin wrapped graphene oxide-sulfur composite was prepared to construct a 3-dimensionally cross-linked structure through the interaction between amylopectin and graphene oxide, for stabilizing lithium sulfur batteries. With the help of this cross-linked structure, the sulfur particles could be confined much better among the layers of graphene oxide and exhibited significantly improved cyclability, compared with the unwrapped graphene oxide-sulfur composite. The effect of the electrode mass loading on electrochemical performance was investigated as well. In the lower sulfur mass loading cells, such as 2 mg cm(-2), both the capacity and the efficiency were obviously better than those of the higher sulfur mass loading cells, such as 6 mg cm(-2). PMID:24007262

Zhou, Weidong; Chen, Hao; Yu, Yingchao; Wang, Deli; Cui, Zhiming; Disalvo, Francis J; Abrua, Hctor D

2013-09-06

396

Reactivity of metal oxide sorbents for removal of sulfur compounds from coal gases at high temperature and pressure  

SciTech Connect

Hot-gas desulfurization for the integrated gasification combined cycle (IGCC) process has been investigated to effectively remove hydrogen sulfide with various metal oxide sorbents at high temperatures and pressures. Metal oxide sorbents such as zinc titanate oxide, zinc ferrite oxide, copper oxide, manganese oxide and calcium oxide were found to be promising sorbents in comparison with other removal methods such as membrane separation and reactive membrane separation. The removal reaction of H{sub 2}S from coal gas mixtures with zinc titanate oxide sorbents was conducted in a batch reactor. The main objectives of this research are to formulate promising metal oxide sorbents for removal of hydrogen sulfide from coal gas mixtures, to compare reactivity of a formulated sorbent with a sorbent supplied by the Research Triangle Institute at high temperatures and pressures, and to determine effects of concentrations of moisture contained in coal gas mixtures on equilibrium absorption of H{sub 2}S into metal oxide sorbents. Promising durable metal oxide sorbents with high-sulfur-absorbing capacity were formulated by mixing active metal oxide powders with inert metal oxide powders and calcining these powder mixtures.

Kwon, K.C.; Crowe, E.R. [Tuskegee Univ., AL (United States); Gangwal, S.K. [Research Triangle Inst., Research Triangle Park, NC (United States)

1997-01-01

397

Conversion of enriched isotopes of sulfur from SF sub 6 to a suitable compound for feed to the electromagnetic calutron separators  

Microsoft Academic Search

Enriched isotopes of sulfur are becoming attractive for use as tracers in a variety of environmental and scientific experiments. many stages of separation are needed, especially for ³³S and ³⁶S, which exist in low natural abundances. Small amounts of highly enriched sulfur isotopes can be provided by means of electromagnetic separation in the calutrons. However, the cost is prohibitively high

H. H. Caudill; W. D. Bond; E. D. Collins; L. E. McBride; H. T. Milton; J. G. Tracy; A. M. Veach; J. W. York

1989-01-01

398

Sulfur Assimilatory Metabolism. The Long and Smelling Road  

Microsoft Academic Search

Sulfur represents the ninth and least abundant essential macronutrient in plants, preceded by carbon, oxygen, hydrogen, nitrogen, potassium, calcium, mag- nesium, and phosphorus. The dry matter of sulfur in plants is only about one-fifteenth of that of nitrogen. Both sulfur and nitrogen are necessary to be assimi- lated into organic metabolites. While nitrogen is mainly used for structural macromolecules, sulfur

Kazuki Saito

2004-01-01

399

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...

400

Sulfur isotopic variations in low-sulfur coals from the Rocky Mountain region  

NASA Astrophysics Data System (ADS)

The isotopic composition of organic sulfur and disseminated and massive pyrite has been determined in vertical sections from eight low-sulfur coals (Paleocene and Cretaceous in age) in four coal fields of Wyoming and Colorado. The 34 S values of organic sulfur from five sites in the Anderson-Wyodak coal (Paleocene) of the eastern Powder River Basin, Wyoming, are more negative than expected for low-sulfur coals (-18.7 to +3.9%), suggesting that organic sulfur was derived from a combination of original plant sulfur and secondary, 34 S-depleted sulfur. The 34 S-depleted sulfur was probably produced from bacterial reduction of sulfate which infiltrated from the top and bottom during the peat stage. The 34 S of organic sulfur in a Paleocene coal from the Hanna Basin, Wyoming, ranges from +1.6 to +13.1 %. Vertical variation in 34 S here suggests bacterial reduction in a partially closed system of sulfate which infiltrated from the top of the seam. A Paleocene and a Cretaceous coal from the Green River Coal region, in Wyoming and Colorado, both yield 34 S values of organic sulfur (+2.4 to +8.1 %) consistent with what would be expected for original plant sulfur. 34 S values of pyrite at all sites varies widely (-52.6 to +34.6%). The isotope composition of the disseminated pyrite correlates with that of the organic sulfur, implying a similar mode and timing of incorporation. 34 S of the massive pyrite shows no such correlation.

Hackley, Keith C.; Anderson, Thomas F.

1986-08-01

401

Process for the separation of sulfur oxides from a gaseous mixture containing sulfur oxides and oxygen  

SciTech Connect

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.

Derosset, A.J.; Ginger, E.A.

1980-12-23

402

Sulfur capture for fluidized-bed combustion of high-sulfur content lignites  

Microsoft Academic Search

Sulfur release and capture behavior of lignites with highly combustible sulfur-contents were investigated by extending a previously-developed comprehensive model to incorporate sulfur retention. The predictive performance of the model was tested by comparing the model predictions with on-line concentration measurements of O2, CO2, CO and SO2. Favorable comparisons are obtained between the predicted and measured concentrations of gaseous species along

Hakan Altindag; Yusuf Gogebakan; Nevin Seluk

2004-01-01

403

Quaternary Marine Sulfur Cycle Dynamics  

NASA Astrophysics Data System (ADS)

Published data show a -0.8% change in marine sulfate ?34S ratios in the past 2 Ma. Prior to this period it was stable at ~ 22% for ~ 50Ma since the Eocene. Compared to the residence time of sulfate (>10 Ma) the observed change is large and implies a major disturbance of the marine sulfur cycle. However, the cause of the disturbance, as well as the timing of its onset are poorly constrained. Here we present a new set of ?34S ratios of marine sulfate for the last 3 Ma with a temporal resolution of ~300ka, which shows a linear decline from 22 to ~21% in the past 1.75Ma. This may represent a change in volcanic and hydrothermal activity, pyrite burial or erosion and weathering of exposed evaporites and sulfides, which are the main processes affecting sulfate ?34S. However, during this period there is no geological evidence for exceptional volcanic and hydrothermal activity and consequently, the observed negative shift reflects either a change in isotopic composition and volume of erosional input of sulfate to the ocean, or a decrease in pyrite burial. The isotopic composition of the input flux depends on the relative proportion of sulfide vs. sulfate weathering. Sedimentary sulfides are mostly concentrated in organic rich sediments on continental shelves. Existing sea level records suggest periodic sea level drops during glacial stages related to the formation of ice sheets. This could affect sulfur cycling in two ways: a) exposure to surface weathering and erosion agents of large parts of continental shelves increased global sulfide oxidation and thus the input flux of sulfate to the ocean and/or b) the reduction of shelf areas resulted in decreased pyrite burial. We explore the effects of these changes with a simple box model. The modeling results indicate that the observed isotopic shift requires a 150% increase of pyrite weathering or a 90% reduction of pyrite burial over the past 1.75Ma. When both of these processes change in concert the same effect is produced with the doubling of pyrite weathering and 50% decrease of pyrite burial. As pyrite burial and organic matter burial are intimately linked, a drastic decrease in pyrite burial should leave its mark in the carbon isotopic record which shows no evidence of a major change in carbon cycling. We thus propose that increased sulfide weathering, either from subaerial exposure, or as a result of increased winnowing might be the principal cause of the negative ?34S shift in the Quaternary.

Markovic, S.; Paytan, A.; Wortmann, U. G.

2011-12-01

404

Sulfur Recovery from Acid Gas Using the Claus Process and High Temperature Air Combustion (HiTAC) Technology  

Microsoft Academic Search

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

Mohamed Sassi; Ashwani K. Gupta

405

Method for removing sulfur dioxide from flue gases  

SciTech Connect

A method is described for removing sulfur oxide compounds from flue gases. The method comprises forming a slurry of calcium oxide and water, exothermically reacting the slurry of calcium oxide and water to form a hydrate containing saturated water and calcium hydroxide, flashing the saturated water to steam to break up the calcium hydroxide into very fine particles and passing the fine particles of calcium hydroxide in a counterflow relationship with the flue gases so that the sulfur oxide compounds from the flue gases are reacted with the calcium hydroxide particles.

Sommerlad, R.E.

1987-05-19

406

Medical Management of Cutaneous Sulfur Mustard Injuries.  

National Technical Information Service (NTIS)

Background: Sulfur mustard (2,2 -dichlorodiethyl sulfide; HD) is a potent vesicating chemical warfare agent that poses a continuing threat to both military and civilian populations. Significant cutaneous HD injuries can take several months to heal, necess...

J. S. Graham L. W. Mitcheltree R. R. Deckert R. S. Stevenson T. A. Hamilton

2009-01-01

407

Low-Sulfur Fuel Oil from Coal.  

National Technical Information Service (NTIS)

A high-sulfur bituminous coal suspended in coal tar was hydrodesulfurized by continuous processing through a fixed bed of pelletized cobalt molybdate on alumina catalyst, under conditions of highly turbulent flow of hydrogen to prevent obstruction of the ...

P. M. Yavorsky S. Akhtar S. Friedman

1971-01-01

408

Analysis of atmospheric sulfur dioxide: a review  

Microsoft Academic Search

Commonly used manual and automatic methods for measurement and monitoring of sulfur dioxide in the atmosphere are critically reviewed. Promising but undeveloped techniques are discussed to stimulate interest in further development. 42 references.

Hochheiser

1967-01-01

409

Sodium and sulfur chemistry in combustion gases.  

National Technical Information Service (NTIS)

In the present work the chemistry of sodium and sulfur in flue gas are examined with respect to deposit formation and corrosion effects. Measurements, industrial as well as laboratory, constitute the basis of the treatment. In the theoretical consideratio...

R. Backman

1989-01-01

410

Sulfuric Acid Regeneration Waste Disposal Technology.  

National Technical Information Service (NTIS)

All U.S. Army Ammunition Plants (AAPs) having sulfuric acid regeneration (SAR) facilities use lime precipitation as the principal means of acid wastewater neutralization. This is as an advanced system as is used in industrial practice. However, lime preci...

A. A. Balasco D. E. Johnson J. J. Stahr J. I. Stevens M. A. Fields

1986-01-01

411

21 CFR 582.3862 - Sulfur dioxide.  

Code of Federal Regulations, 2013 CFR

...3862 Section 582.3862 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT...RECOGNIZED AS SAFE Chemical Preservatives § 582.3862 Sulfur dioxide...that it is not used in meats or in food recognized as source of...

2013-04-01

412

21 CFR 182.3862 - Sulfur dioxide.  

Code of Federal Regulations, 2013 CFR

...3862 Section 182.3862 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT...HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN CONSUMPTION (CONTINUED...RECOGNIZED AS SAFE Chemical Preservatives § 182.3862 Sulfur...

2013-04-01

413

Process for Producing Sulfurous Acid Treated Alumina.  

National Technical Information Service (NTIS)

The activated alumina is effective for bleaching refined cottonseed oil. It is prepared by soaking ground activated alumina with an aqueous solution of sulfurous acid until a specific saturation is reached. The alumina is then removed from the solution an...

W. A. Pons J. C. Kuck V. L. Frampton

1964-01-01

414

Neutralization and Biodegradation of Sulfur Mustard.  

National Technical Information Service (NTIS)

The chemical warfare agent sulfur mustard was hydrolyzed to products that were biologically mineralized in sequencing batch reactors seeded with activated sludge. Greater than 90% carbon removal was achieved using laboratory scale bioreactors processing h...

S. P. Harvey L. L. Szafraniec W. T. Beaudry J. T. Earley R. L. Irvine

1997-01-01

415

Biologically produced sulfur particles and polysulfide ions  

Microsoft Academic Search

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

W. E. Kleinjan

2005-01-01

416

Sulfur Acidity Loading in South Korean Ecosystems  

Microsoft Academic Search

The applicability of critical load (CL) methodology for thedetermination of natural terrestrial ecosystem sensitivity to sulfur acidity loading in South Korea was investigated.The sulfur critical load values, CLmaxS, were calculated for the terrestrial ecosystems of South Korea using the steady-state mass balance approach. The corresponding mapping of CLmaxS was carried out on the scale of 11 14 km grid

Soon-Ung Park; Vladimir Bashkin

2001-01-01

417

Polarization measurements in sodium-sulfur cells  

SciTech Connect

This paper reports on measurements of discharge polarization in 40 Ah sodium-sulfur cells that have been performed. The voltage relaxation rate as a function of state of charge was monitored over a period of several hours. Relaxations of the order of seconds were determined using an ac impedance technique. The data were combined to construct an impedance model of a sodium-sulfur cell which includes a Warburg term which varies as a function of state of charge.

Johnson, P.J. (Chloride Silent Power, Ltd., Runcorn, Cheshire WA7 1PZ (GB)); Koening, A.A. (Beta Power, Inc., Wayne, PA (US))

1990-04-01

418

Multiple sulfur isotopes and the evolution of the atmosphere  

Microsoft Academic Search

Interest in multiple sulfur isotope analyses has been fueled by recent reports of mass-independent sulfur isotope signatures in the geologic record. A non-zero multiple isotopic signature of sulfur (?33S and ?36S) is produced primarily through photochemical reactions, and it is an almost perfect tracer of the source of sulfur. Once the signature is passed on to a given sulfur reservoir,

James Farquhar; Boswell A. Wing

2003-01-01

419

Early generation characteristics of a sulfur-rich Monterey kerogen  

Microsoft Academic Search

This paper documents the critical role of organic sulfur in the early formation of bitumen and oil from a sulfur-rich kerogen from the Miocene Monterey Formation in California. Monterey kerogen commonly contains abundant chemically bound sulfur (8-14 wt %) which appears responsible for early, low-temperature generation of heavy, sulfur-rich petroleum due to the lower energy required to break carbon-sulfur bonds

D. K. Baskin; K. E. Peters

1992-01-01

420

Microphysical simulations of sulfur burdens from stratospheric sulfur geoengineering  

NASA Astrophysics Data System (ADS)

Recent microphysical studies suggest that geoengineering by continuous stratospheric injection of SO2 gas may be limited by the growth of the aerosols. We study the efficacy of SO2, H2SO4 and aerosol injections on aerosol mass and optical depth using a three-dimensional general circulation model with sulfur chemistry and sectional aerosol microphysics (WACCM/CARMA). We find increasing injection rates of SO2 in a narrow band around the equator to have limited efficacy while broadening the injecting zone as well as injecting particles instead of SO2 gas increases the sulfate burden for a given injection rate, in agreement with previous work. We find that injecting H2SO4 gas instead of SO2 does not discernibly alter sulfate size or mass, in contrast with a previous study using a plume model with a microphysical model. However, the physics and chemistry in aircraft plumes, which are smaller than climate model grid cells, need to be more carefully considered. We find equatorial injections increase aerosol optical depth in the Northern Hemisphere more than the Southern Hemisphere, potentially inducing regional climate changes. We also find significant perturbations to tropospheric aerosol for all injections studied, particularly in the upper troposphere and near the poles, where sulfate burden increases by up to 100 times. This enhanced burden could have implications for tropospheric radiative forcing and chemistry. These results highlight the need to mitigate greenhouse gas emissions through means other than geoengineering, and to further study geoengineering before it can be seriously considered as a climate intervention option.

English, J. M.; Toon, O. B.; Mills, M. J.

2012-01-01

421

Volcanogenic Sulfur on Earth and Io: Composition and Spectroscopy  

USGS Publications Warehouse

The causes of Io's variegated surface, especially the roles of sulfur, and the geochemical history of sulfur compounds on Io are not well understood. Suspecting that minor impurities in sulfur might be important, we have investigated the major and trace element chemistry and spectroscopic reflectance of natural sulfur from a variety of terrestrial volcanic-hydrothermal environments. Evidence suggests that Io may be substantially coated with impure sulfur. On Earth, a few tenths of a percent to a few percent of chalcophile trace elements (e.g., As and Se) comonly occur in sulfur and appear to stabilize material of yellow, brown, orange, and red hues, which may persist even at low temperatures. Percentage levels of chalcophile impurities are reasonably expected to occur on Io in vapor sublimate deposits and flows derived from such deposits. Such impurities join a host of other mechanisms that might explain Io's reds and yellows. Two-tenths to two percent opaque crystalline impurities, particularly pyrite (FeS2), commonly produces green, gray, and black volcanic sulfur on Earth and might explain areas of Io having deposits of these colors. Pyrite produces a broad absorption near 1 ??m that gradually diminishes out to 1.6 ??m - similar but not identical to the spectrum of Io seen in Galileo NIMS data. Percentage amounts of carbonaceous impurities and tens of percent SiO2 (as silicates) also strongly affect the spectral properties of Earth's sulfur. Io's broad absorption between 0.52 and 0.64 ??m remains unexplained by these data but could be due to sodium sulfides, as suggested previously by others, or to As, Se, or other impurities. These impurities and others, such as P and Cl (which could exist on Io's surface in amounts over 1% that of sulfur), greatly alter the molecular structure of molten and solid sulfur. Minor impurities could impact Io's geology, such as the morphology of sulfur lava flows and the ability of sulfur to sustain high relief. We have not found any natural sulfur containing significant Na beyond that attributable to silicate inclusions. In sum, the unique physical-chemical properties of S-rich systems and the strong affinity of certain elements for S may have broad implications for the appearance, spectroscopic interpretation, and geologic processes of Io. Identification of impurities in sulfur may be helpful in tracing the geochemical evolution of surface deposits on Io. Perhaps foretelling of new areas of investigation, Cl has recently been reported in the Io torus (M. Kueppers and N. M. Schneider 1999, Eos Trans.80, 5207), suggesting the presence on Io of either salts, such as halite, or sulfur chlorides. Further evidence of minor iogenic impurities should be sought in Io's neutral cloud and plasma torus as well as in further scrutiny of Io's reflectance spectra. ?? 1999 Academic Press.

Kargel, J. S.; Delmelle, P.; Nash, D. B.

1999-01-01

422

Effects of high salinity and constituent organic compounds on treatment of photo-processing waste by a sulfur-oxidizing bacteria/granular activated carbon sludge system.  

PubMed

To achieve practical treatment of photo-processing waste (PW) using our previously proposed sulfur-oxidizing bacteria (SOB)/granular activated carbon (GAC) sludge system, this paper elucidates why 3- to 5-X dilution of PW was required. That is, a series of experiments were carried out to show the effects of high salinity and constituent organic compounds in PW, respectively. Both an inorganic salts system and calcination PW system showed that SOB completely oxidizes S2O(3)2- -S to SO(4)2- -S even at 12.3 or 13.6% salinity, respectively; hence the dilution requirement is not attributable to high salinity. In experiments employing SOB and SOB/GAC systems to investigate the effects of 23 constituent compounds in PW, compounds were classified into Groups I, II, IIIa, and IIIb. Even with 10 g/l GAC, the nine compounds in Group IIIb still exhibited a toxic effect on SOB activity at 1- and 3-X dilutions; thus it is these compounds that are responsible for requiring dilution of PW. Accordingly, a reduction in their use within the photodeveloping and fix-stabilizing industry, and/or use of > 10g/l GAC, are new considerations for establishing a more practical PW treatment process. PMID:11848345

Lin, Bin-Le; Hosomi, Masaaki; Murakami, Akihiko

2002-02-01

423

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

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.

Ehizele, AO; Akhionbare, O

2013-01-01

424

Process and apparatus for generating elemental sulfur and re-usable metal oxide from spent metal sulfide sorbents  

DOEpatents

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.

Ayala, Raul E. (Clifton Park, NY); Gal, Eli (Lititz, PA)

1995-01-01

425

Taxing sulfur dioxide emission allowances  

SciTech Connect

The acid rain control program authorized by Title IV of the Clean Air Act Amendments of 1990 (CAAA) was designed to reduce the adverse effects of acid rain by limiting emissions of sulfur dioxide (SO[sub 2]) into the atmosphere. The program is a complex scheme involving the issuance, consumption, holding, and trading of emission allowances for SO[sub 2]. Not surprisingly, electric utilities will face federal income tax issues in connection with the program. Under the emission allowance program, the U.S. Environmental Protection Agency (EPA) will issue emission allowance to owners or operators of certain utility power plants at no cost to the recipients. An emission allowance is an authorization to emit one ton of SO[sub 2] during or after the calendar year for which it is issued. If a utility power plant subject to the program emits SO[sub 2] in excess of its allowances, the owner or operator will be subject to a penalty of $2,000 a ton, and must offset the excess emissions with allowances in the subsequent year. Allowances may be bought and sold. Phase I of the program begins January 1, 1995, and will apply to 110 utility generating units. Phase II takes effect January 1, 2000, and will include most electric utility generating units. EPA will withhold a specified number of allowances for direct sale and auction. The resulting proceeds will be paid to the utilities from which the allowances were withheld. The Internal Revenue Service (IRS) has provided somewhat limited guidance on several tax issues raised by the program. Significant tax issues and the positions articulated by the IRS (if any) are discussed in this article.

Nelson, G.L. (Reid Priest, Washington, DC (United States))

1993-09-15

426

Coal gasification pilot plant support studies. Subtask 3-3. Improved methods of removal, recovery, or conversion of sulfur and nitrogen compounds in raw product gases from coal gasification processes  

SciTech Connect

Results are reported from three exploratory programs to improve the processing techniques for the removal, conversion, or recovery of sulfur and nitrogen compounds without gas quenching in coal gasification processes. The areas of investigation were the following: (1) fuel gas desulfurization, (2) catalytic ammonia decomposition in fuel gas streams, and (3) catalytic hydrolysis of carbonyl sulfide in fuel gas streams.

Not Available

1980-12-01

427

He(I)\\/He(II) ultraviolet photoelectron spectroscopic studies on organosulfur compounds with emphasis on the sulfuroxygen interaction 1 In honor of Professor rpad Kucsman on the occasion of his 70th birthday. 1  

Microsoft Academic Search

The electronic structure of compounds having the possibility of exhibiting intramolecular sulfuroxygen non-bonded interaction of the S(II, IV or VI)?O(carbonyl or nitro) type and a hypervalent sulfur atom of the OSO type i.e, RSMe, RSOMe, RSO2Me (R=2-nitrophenyl; 2, 7 and 12), RSR, RSOR, RSO2R (R=2-methoxycarbonylphenyl; 5, 10 and 15) and spirosulfurane (16) have been investigated by the He(I)

Istvn Pl Csonka; Gbor Vass; Lszl Szepes; Dnes Szab; Istvn Kapovits

1998-01-01

428

Nashville Sulfur Dioxide Emission Inventory and the Relationship of Emission to Measured Sulfur Dioxide  

Microsoft Academic Search

A detailed inventory of sulfur dioxide emissions was prepared as part of the Nashville Community Air Pollution Study conducted by the Public Health Service during 195859. The primary purpose of the inventory was to provide data for a study of the relationship between the emission of sulfur dioxide and measured ambient levels. The development of the inventory, data collection methods,

W. W. Stalker; P. A. Kenline; H. J. Paulus

1964-01-01

429

Sulfur Variations in Glasses from Volcanic Rocks: Effect of Melt Composition on Sulfur Solubility  

Microsoft Academic Search

A worldwide data set of major element and sulfur analyses of undegassed lavas, pumices, and melt inclusions from 14 volcanic locations was selected to investigate the compositional effects on sulfur solubility in magmas. We utilized analyses on calc-alkaline, alkaline, and tholeiitic rocks, with a range of 3400 ppm S variation. There is a strong correlation between chemical composition and the

Mihai N. Ducea; Brent I. A. Mcinnes; Peter J. Wyllie

1994-01-01

430

EFFECT OF PYRITIC SULFUR AND MINERAL HATTER ON ORGANIC SULFUR REMOVAL FROM COAL  

Microsoft Academic Search

The perchloroethylene coal cleaning process uses perchloroethylene as the solvent to remove both organic and inorganic forms of sulfur without any significant loss to its calorific value. The process removes these forms of sulfur in two sequential unit steps. The objective of this investigation was to determine the exact sequence of operations in the Process. Hence, organosulfur was removed before

Padmakar Vishnubhatt; Theodore Thome; Sunggyu Lee

1993-01-01

431

Sulfur isotope fractionation during the reduction of elemental sulfur and thiosulfate by Dethiosulfovibrio spp.  

NASA Astrophysics Data System (ADS)

Thiosulfate and elemental sulfur are typical by-products of the oxidation of dissolved sulfide and important sulfur intermediates in the biogeochemical sulfur cycle of natural sediments where they can be further transformed by microbial or chemical oxidation, reduction, or disproportionation. Due to the often superimposing reaction pathways of the sulfur intermediates in natural environments specific tracers are needed to better resolve the complex microbial and biogeochemical reactions. An important fingerprint for sulfur cycling is provided by the microbial fractionation of the stable sulfur isotopes S-34 and S-32. Proper interpretation of isotope signals in nature, however, is only possible by the calibration with results obtained with pure cultures under defined experimental conditions. In addition, sulfur isotope discrimination may provide informations about specific encymatic biochemical pathways within the bacterial cells. In this study, we report the results for the discrimination of stable sulfur isotopes S-32 and S-34 during reduction of thiosulfate and elemental sulfur by non-sulfate, but sulfur- and thiosulfate-reducing bacteria which are phylogenetically not related to sulfate-reducing bacteria. Experiments with were conducted at known cell-specific thiosulfate reduction rates. Stable sulfur isotope fractionation was investigated during reduction of thiosulfate and elemental sulfur at 28C by growing batch cultures of Dethiosulfovibrio marinus WS100 (type strain DSM 12537) and Dethiosulfovibrio russensis (type strain DSM 12538) using citrate as carbon and energy source. The cell-specific reduction rates were 0.3 to 2.4 fmol cell-1 d-1 (thiosulfate) and 31 to 38 fmol cell-1 d-1 (elemental sulphur), respectively. The sulfide produced was depleted in S-34 by 12 per mil compared to total thiosulfate sulfur, close to previous results observed for sulfate-reducing bacteria, indicating that the thiosulfate-reducing mechanism of sulfate reducers is similar to that of the investigated thiosulfate-reducing strains. Elemental sulfur reduction yields sulfide depleted in S-34 and isotope fractionation effects between 1.3 and 5.2 per mil for Dethiosulfovibrio russensis and 1.7 and 5.1 per mil Dethiosulfovibrio marinus, with the smaller fractionation effects observed in the exponential growth phase and enhanced discrimination under conditions of citrate depletion and cell lysis.

Surkov, A. V.; Bttcher, M. E.; Kuever, J.

2009-04-01

432

Sulfur accumulation in the timbers of King Henry VIII's warship Mary Rose: A pathway in the sulfur cycle of conservation concern  

PubMed Central

In marine-archaeological oak timbers of the Mary Rose large amounts of reduced sulfur compounds abound in lignin-rich parts such as the middle lamella between the cell walls, mostly as thiols and disulfides, whereas iron sulfides and elemental sulfur occur in separate particles. Synchrotron-based x-ray microspectroscopy was used to reveal this environmentally significant accumulation of organosulfur compounds in waterlogged wood. The total concentration of sulfur in reduced forms is ?1 mass % throughout the timbers, whereas iron fluctuates up to several mass %. Conservation methods are being developed aiming to control acid-forming oxidation processes by removing the reactive iron sulfides and stabilizing the organosulfur compounds.

Sandstrom, Magnus; Jalilehvand, Farideh; Damian, Emiliana; Fors, Yvonne; Gelius, Ulrik; Jones, Mark; Salome, Murielle

2005-01-01

433

Accelerated Corrosion of Printed Circuit Boards due to High Levels of Reduced Sulfur Gasses in Industrial Environments  

Microsoft Academic Search

Accelerated corrosion leading to system failure has been observed on printed circuit boards present in industrial environments that contain abnormal levels of reduced sulfur gasses, such as hydrogen sulfide (H2S) and elemental sulfur. The problem is compounded by the fact that elemental sulfur is regulated by OSHA as a nuisance dust, and is allowed in a human working environment at

Paul Mazurkiewicz

434

Role of Cystathionine Lyase in Catabolism of Amino Acids to Sulfur Volatiles by Genetic Variants of Lactobacillus helveticus CNRZ 32  

Microsoft Academic Search

Catabolism of sulfur-containing amino acids plays an important role in the development of cheese flavor. During ripening, cystathionine -lyase (CBL) is believed to contribute to the formation of volatile sulfur compounds (VSCs) such as methanethiol and dimethyl disulfide. However, the role of CBL in the generation of VSCs from the catabolism of specific sulfur-containing amino acids is not well characterized.

Won-Jae Lee; Dattatreya S. Banavara; Joanne E. Hughes; Jason K. Christiansen; James L. Steele; Jeffery R. Broadbent; Scott A. Rankin

2007-01-01

435

Workshop on sulfur chemistry in flue gas desulfurization  

SciTech Connect

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)

Wallace, W.E. Jr.

1980-05-01

436

Emission of reduced malodorous sulfur gases from wastewater treatment plants  

SciTech Connect

The emission of malodorous gaseous compounds from wastewater collection and treatment facilities is a growing maintenance and environmental problem. Numerous gaseous compounds with low odor detection thresholds are emitted from these facilities. Sulfur-bearing gases represent compounds with the lowest odor detection threshold. Using solid adsorbent preconcentration and gas chromatographic methods, the quantity and composition of reduced malodorous sulfur gases emitted from various steps of the treatment process were determined in wastewater treatment plants in Baton Rouge, Louisiana. Hydrogen sulfide, which is a malodorous, corrosive, and potentially toxic gas, was the most dominant volatile reduced sulfur (S) compound measured. Concentrations were not only more than the odor detection threshold of hydrogen sulfide, but above levels that may affect health during long-term exposure. The concentrations of methanethiol, dimethyl sulfide, carbon disulfide, and carbonyl sulfide were significantly less than hydrogen sulfide. However, even though emissions of reduced sulfur gases other than hydrogen sulfide were low, previous studies suggested that long-term exposure to such levels may cause respiratory problems and other symptoms.

Devai, I.; DeLaune, R.D.

1999-03-01

437

40 CFR 60.104 - Standards for sulfur oxides.  

Code of Federal Regulations, 2013 CFR

...fuel gas combustion device any fuel gas that contains hydrogen sulfide (H2 S) in excess of 230 mg/dscm (0.10...reduced sulfur compounds and 10 ppm by volume of hydrogen sulfide (H2 S), each calculated as ppm SO2 by...

2013-07-01

438

Dynamic simulation of sulfur-removal systems. Final report  

Microsoft Academic Search

A generalized computer simulation has been developed to predict the dynamic response of alternate gas absorption systems for selective removal of sulfur compounds or ammonia from fuel gas or synthesis gas produced from coal or other fossil fuels. The models use numerical methods based upon finite difference techniques to determine the spatial distribution of process variables within both the absorption

J. H. Alexander; T. R. Blake; D. H. Jr. Brownell; W. D. Henline; D. E. Wilkins

1982-01-01

439

Growth kinetics of haloalkaliphilic, sulfur-oxidizing bacterium Thioalkalivibrio versutus strain ALJ 15 in continuous culture  

Microsoft Academic Search

The chemolithoautotrophic, sulfur-oxidizing bacterium Thioalkalivibrio versutus strain ALJ 15, isolated from a soda lake in Kenya, was grown in a continuous culture, with thiosulfate or polysulfide as growth-limiting energy source and oxygen as electron acceptor, at pH 10 and at pH 0.6, 2M and 4M total sodium. The end product of the sulfur-compound oxidation was sulfate. Elemental sulfur and a

Horia Banciu; Dimitry Y. Sorokin; Robbert Kleerebezem; Gerard Muyzer; Erwin A. Galinski; J. Gijs Kuenen

2004-01-01

440

Clues to early diagenetic sulfurization processes from mild chemical cleavage of labile sulfur-rich geomacromolecules  

NASA Astrophysics Data System (ADS)

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.

Adam, P.; Schneckenburger, P.; Schaeffer, P.; Albrecht, P.

2000-10-01

441

Ametryne and prometryne as sulfur sources for bacteria.  

PubMed

Bacteria were isolated that could utilize quantitatively the s-triazine herbicide prometryne [N,N' -bis(1-methylethyl)-6-(methylthio)-1,3,5-triazine-2,4-diamine] or ametryne [N-ethyl-N'-(1-methylethyl)-6-(methylthio)-1,3,5-triazine- 2,4-diamine], or both, as a sole source of sulfur for growth. The success of enrichments depended on previous exposure of the soil inoculum to s-triazine herbicides. Deaminoethylametryne [4-(1-methylethyl)amino-6-(methylthio)-1,3,5-triazine-2-(1H)-one], methylsulfonic acid, and sodium sulfate could also be used as sulfur sources. Utilization of a compound was quantified as the growth yield per mole of sulfur supplied. Yields were about 6 kg of protein per mol of sulfur. The product of the desulfuration of an s-triazine was identified as the corresponding hydroxy-derivative. This is the first substantiated report of the utilization of these s-triazines as sulfur sources by bacteria. PMID:16345988

Cook, A M; Htter, R

1982-04-01

442

Ametryne and Prometryne as Sulfur Sources for Bacteria  

PubMed Central

Bacteria were isolated that could utilize quantitatively the s-triazine herbicide prometryne [N,N? -bis(1-methylethyl)-6-(methylthio)-1,3,5-triazine-2,4-diamine] or ametryne [N-ethyl-N?-(1-methylethyl)-6-(methylthio)-1,3,5-triazine- 2,4-diamine], or both, as a sole source of sulfur for growth. The success of enrichments depended on previous exposure of the soil inoculum to s-triazine herbicides. Deaminoethylametryne [4-(1-methylethyl)amino-6-(methylthio)-1,3,5-triazine-2-(1H)-one], methylsulfonic acid, and sodium sulfate could also be used as sulfur sources. Utilization of a compound was quantified as the growth yield per mole of sulfur supplied. Yields were about 6 kg of protein per mol of sulfur. The product of the desulfuration of an s-triazine was identified as the corresponding hydroxy-derivative. This is the first substantiated report of the utilization of these s-triazines as sulfur sources by bacteria.

Cook, Alasdair M.; Hutter, Ralf

1982-01-01

443

Dramatic changes in geometry after ionization: experimental and theoretical studies on the electronic properties of fluorocarbonyl (mono-, di-, and tri-) sulfur compounds.  

PubMed

In this work, we present a complete study on He I photoelectron spectroscopy (PES) for the fluorocarbonyl mono-, di-, and trisulfur compounds FC(O)SCl, FC(O)SSCH(3), and FC(O)SSSC(O)F. After optimizations of the structure for stable conformers at different levels of theory, a complete theoretical study involving the calculation of the ionization energies using orbital valence Green's functional (OVGF) was performed. Calculations of radical-cationic forms were carried out in order to compare their properties with those of the neutral molecules. The first IP values are 10.7, 9.0, and 10.5 eV for FC(O)SCl, FC(O)SSCH(3), and FC(O)SSSC(O)F, respectively. The groups bonded to the S atom mainly influence the ionizations originating from the sulfur lone pairs. A wide electronic delocalization in the FC(O)S moiety can be deduced from experimental and theoretical results, which leads to a strong energetic stabilization of the n' '(S) (sulfur lone pair pi orbital). Other conclusions relate to effects on the substituents attached to the S atom and the importance of the molecular planarity in the orbital stabilization of the FC(O)S moiety for the neutral molecules. It is worthwhile mentioning that FC(O)SCl retains its planar structure after ionization, but drastic changes occur in the geometry of both FC(O)SSCH(3) and FC(O)SSSC(O)F. The FC(O)SSCH(3) molecule adopts a heavy atom planar structure after ionization. The FC(O)SSS moiety becomes a planar form after the ionization of the FC(O)SSSC(O)F molecule, whereas the second C(O)F group maintains its original conformation with respect to the SSS group. PMID:12099879

Erben, Mauricio F; Della Vdova, Carlos O

2002-07-15

444

Io: longitudinal distribution of sulfur dioxide frost.  

PubMed

Twenty spectra of Io (0.26 to 0.33 micrometer), acquired with the International Ultraviolet Explorer spacecraft, have been studied. There is a strong ultraviolet absorption shortward of 0.33 micrometer that is consistent with earlier ground-based spectrophotometry; its strength is strongly dependent on Io's rotational phase angle at the time of observation. This spectral feature and its variation are interpreted as indicative of a longitudinal variation in the distribution of sulfur dioxide frost on Io. The frost is most abundant at orbital longitudes 72 degrees to 137 degrees and least abundant at longitudes 250 degrees to 323 degrees . Variations in spectral reflectivity between 0.4 and 0.5 micrometer, reported in earlier ground-based spectral studies, correlate inversely with variations in reflectivity between 0.26 and 0.33 micrometer. It is concluded that this is because the Io surface component with the highest visible reflectivity (sulfur dioxide frost) has the lowest ultraviolet reflectivity. At least one other component is present and may be sulfur allotropes or alkali sulfides. This model is consistent with ground-based ultraviolet, visible, and infrared spectrophotometry. Comparison with Voyager color photographs indicates that the sulfur dioxide frost is in greatest concentration in the "white" areas on Io and the other sulfurous components are in greatest concentration in the "red" areas. PMID:17739547

1980-11-14

445

Sulfur Particles on the Early Earth  

NASA Astrophysics Data System (ADS)

Understanding the atmosphere of the early Earth during the Archean, the period of time approximately 4 - 2.45 billion years ago, is an important part of understanding the conditions under which life originated and developed. The presence of sulfur mass independent fractionation (S-MIF) in Archean sediments is thought to be evidence for an early anoxic atmosphere. Photolysis of sulfur dioxide (SO2) by UV light with ?<220 nm has been shown in models and some initial laboratory studies to create a S-MIF fractionation; however, sulfur must leave the atmosphere in at least two chemically different forms to preserve any S-MIF signature. It has been suggested that atmospheric reactions in a reducing atmosphere could favor S8 particles over sulfuric acid particles. Here we use aerosol mass spectrometry to probe the chemical composition of particles formed from reactions of sulfur dioxide under a range of atmospheric conditions. We find that S8 formation is enhanced in the presence of reducing species, such as H2 (with electrical discharge as the energy source for reaction) and CH4 (using UV light with wavelengths from 115-400 nm to initiate reaction). Additionally, organosulfur species are formed from the photochemical reaction of SO2 and CH4. These species could be important in the later Archean when methanogenic bacteria could provide a source of CH4 to the atmosphere. Implications for the early Earth are discussed.

Hasenkopf, C. A.; Dewitt, H.; Trainer, M. G.; Farmer, D.; Jimenez, J. L.; McKay, C. P.; Toon, O. B.; Tolbert, M. A.

2010-12-01

446

Development of enhanced sulfur rejection processes  

SciTech Connect

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.

Yoon, R.H.; Luttrell, G.; Adel, G.; Richardson, P.E.

1993-03-23

447

LIVER INJURY, LIVER PROTECTION, AND SULFUR METABOLISM  

PubMed Central

Protein-depleted dogs are very susceptible to injurious agentsin particular, chloroform. Methionine given shortly before chloroform anesthesia will give complete protection against chloroform. Methionine (or cysteine plus choline) given 3 or 4 hours after chloroform anesthesia will give significant protection against the liver injury of chloroform anesthesia. Methionine given more than 4 hours after chloroform anesthesia gives no protection against liver injury. Choline alone given before chloroform gives no protection against liver injury. The protein-depleted dogs have livers which are deficient in both nitrogen and sulfur, but sulfur is depleted more than is the nitrogen. The N/S ratio therefore rises. Methionine or cystine feeding promptly makes up this liver sulfur deficit. Viable liver cells are necessary for this uptake of sulfur. Livers of fetuses in utero or of newborn pups tolerate a chloroform anesthesia which will cause fatal liver injury in adults. The nitrogen and sulfur values of these fetus or pup livers are within the high normal values for adults. Blood-forming cells are present in the fetus or pup livers during this period. When these blood islands are eliminated during the 3rd or 4th week of life, the liver then becomes normally susceptible to chloroform liver injury. Methionine or methionine-rich protein digests (e.g. casein) or various proteins by mouth or by vein should prove useful to protect the liver against certain types of injury and to aid in organ repair.

Miller, L. L.; Whipple, G. H.

1942-01-01

448

Conversion of enriched isotopes of sulfur from SF sub 6 to a suitable compound for feed to the electromagnetic calutron separators  

SciTech Connect

Enriched isotopes of sulfur are becoming attractive for use as tracers in a variety of environmental and scientific experiments. many stages of separation are needed, especially for {sup 33}S and {sup 36}S, which exist in low natural abundances. Small amounts of highly enriched sulfur isotopes can be provided by means of electromagnetic separation in the calutrons. However, the cost is prohibitively high for enrichment of large amounts needed by many experiments. Thus, a two-stage process is planned to obtain large amounts using gas centrifuges for preenrichment, followed by final enrichment in the calutrons. Sulfur hexafluoride is the most efficient form for processing sulfur in the centrifuges; however, SF{sub 6} is unacceptable as feed to the calutrons because it has excellent insulating properties for the high voltage apparatus used to ionize the feed. An efficient process is needed to convert the preenriched sulfur isotopes from SF{sub 6} to a suitable form for calutron feed. Development of a process is difficult because of the relatively high stability of SF{sub 6}. Reiner and Simmons have successfully converted SF{sub 6} to SO{sub 2} in pilot studies using a propane/oxygen flame reactor. However, H{sub 2}S is a more desirable intermediate for producing metal sulfides or sulfur halides. Thus, experiments have been made using direct hydrogenation at temperatures of >900{degrees}C. Conversion to cadmium sulfide has been accomplished by scrubbing the H{sub 2}S product gas with 5% CdCl{sub 2} and product yields of >90% have been achieved. A developmental program to convert SF{sub 6} to CdS, or another more efficient form is being carried out. Optimum conditions for the conversion are being determined and the products are being evaluated in calutron test runs. 7 refs., 5 figs., 2 tabs.

Caudill, H.H.; Bond, W.D.; Collins, E.D.; McBride, L.E.; Milton, H.T.; Tracy, J.G.; Veach, A.M.; York, J.W. (Professional Analysis, Inc., Oak Ridge, TN (USA); Oak Ridge National Lab., TN (USA))

1989-01-01

449

Ferrihydrite-Dependent Growth of Sulfurospirillum deleyianum through Electron Transfer via Sulfur Cycling  

PubMed Central

Observations in enrichment cultures of ferric iron-reducing bacteria indicated that ferrihydrite was reduced to ferrous iron minerals via sulfur cycling with sulfide as the reductant. Ferric iron reduction via sulfur cycling was investigated in more detail with Sulfurospirillum deleyianum, which can utilize sulfur or thiosulfate as an electron acceptor. In the presence of cysteine (0.5 or 2 mM) as the sole sulfur source, no (microbial) reduction of ferrihydrite or ferric citrate was observed, indicating that S. deleyianum is unable to use ferric iron as an immediate electron acceptor. However, with thiosulfate at a low concentration (0.05 mM), growth with ferrihydrite (6 mM) was possible and sulfur was cycled up to 60 times. Also, spatially distant ferrihydrite in agar cultures was reduced via diffusible sulfur species. Due to the low concentrations of thiosulfate, S. deleyianum produced only small amounts of sulfide. Obviously, sulfide delivered electrons to ferrihydrite with no or only little precipitation of black iron sulfides. Ferrous iron and oxidized sulfur species were produced instead, and the latter served again as the electron acceptor. These oxidized sulfur species have not yet been identified. However, sulfate and sulfite cannot be major products of ferrihydrite-dependent sulfide oxidation, since neither compound can serve as an electron acceptor for S. deleyianum. Instead, sulfur (elemental S or polysulfides) and/or thiosulfate as oxidized products could complete a sulfur cycle-mediated reduction of ferrihydrite.

Straub, Kristina L.; Schink, Bernhard

2004-01-01

450

One-step synthesis of a sulfur-impregnated graphene cathode for lithium-sulfur batteries.  

PubMed

A practical route is introduced for synthesizing a sulfur-impregnated graphene composite as a promising cathode material for lithium-sulfur batteries. Sulfur particles with a size of a few microns are successfully grown in the interior spaces between randomly dispersed graphene sheets through a heterogeneous crystal growth mechanism. The proposed route not only enables the control of the particle size of active sulfur but also affords quantitative yields of composite powder in large quantities. We investigate the potential use of the sulfur-impregnated graphene composite as a cathode material owing to its advantages of confining active sulfur, preventing the dissolution of soluble polysulfides, and providing sufficient electrical conduction. A high discharge capacity of 1237 mA h g(-1) during the first cycle and a good cyclic retention of 67% after 50 cycles are attained in a voltage range of 1.8-2.6 V vs. Li/Li(+). These results emphasize the importance of tailoring cathode materials for improving the electrochemical properties of lithium-sulfur batteries. Our results provide a basis for further investigations on advanced lithium batteries. PMID:22481469

Park, Min-Sik; Yu, Ji-Sang; Kim, Ki Jae; Jeong, Goojin; Kim, Jae-Hun; Jo, Yong-Nam; Hwang, Uk; Kang, Shin; Woo, Taewoo; Kim, Young-Jun

2012-04-01

451

Sulfur contents and sulfur-isotope compositions of thiotrophic symbioses in bivalve molluscs and vestimentiferan worms  

USGS Publications Warehouse

Total sulfur (S(TOT)), elemental sulfur (S??) and sulfur-isotope compositions (??34S) of marine animals were analyzed to determine whether these chemical characteristics could help distinguish animals with a sulfur-based, thiotrophic nutrition from animals whose nutrition is based on methanotrophy or on more normal consumption of phytoplankton-derived organic matter. The presence of S??was almost entirely confined to the symbiont-containing tissues of thiotrophs, but was sometimes undetectable in thiotrophic species where sulfide availability was probably low. When S??contents were subtracted, the remaining tissue-sulfur concentrations were similar for all nutritional groups. ??34S values were typically lower for thiotrophs than for other groups, although there was overlap in methanotroph and thiotroph values at some sites. Field evidence supported the existence of small to moderate (1 to 10???)34S fractionations in the uptake of sulfides and metabolism of thiosulfate. In general, a total sulfur content of >3% dry weight, the presence of elemental sulfur, and ??34S values less than + 5??? can be used to infer a thiotrophic mode of nutrition.

Vetter, R. D.; Fry, B.

1998-01-01

452

The Abundance of Sulfur in Venus Magmas  

NASA Astrophysics Data System (ADS)

Outgassing of sulfur gases due to volcanism within the past 100 My on Venus is probably responsible for the planet's globally encircling H2SO4 cloud layers. Dramatic changes in volcanic output on Venus would have altered the atmospheric inventory of sulfur gases, and hence the structure of its clouds (Bullock and Grinspoon, Icarus, submitted 1999). Although Magellan radar images provide some constraints on the magnitude of volcanism in the geologically recent past, little is known of the sulfur content of Venus lavas. In order to assess the effects that Venus' volcanic history may have had on cloud and therefore climate change, it is desirable to place some constraints on the abundance of sulfur in Venus magmas. The sulfur content of terrestrial volcanic lavas varies widely, depending upon the local sedimentary environment and the source and history of upwelling magmas. We estimate the average abundance of sulfur in Venus lavas from an analysis of the production and loss of atmospheric SO2. The volumetric rate of resurfacing on Venus in the recent past is approximately 0.1 to 2 km3/yr (Bullock et al., JGR 20, 1993, Basilevsky and Head, GRL 23, 1996). Outgassed SO2 reacts quickly with crustal carbonate -- residence times in the atmosphere with respect to the reaction SO2 + CaCO3 <=> CaSO4 + CO are about 2-30 My (Fegley and Prinn, Nature 337, 1989, Bullock and Grinspoon, Icarus, submitted 1999). Assuming steady state conditions and an abundance of 25-180 ppm of atmospheric SO2 (Oyama et al., JGR 85, 1980, Bertaux et al., JGR 101, 1996), we will discuss constraints on the abundance of this important greenhouse and cloud-precursor gas in Venus lavas.

Bullock, M. A.; Grinspoon, D. H.

1999-09-01

453

Stable Carbon and Sulfur Isotopes as Records of the Early Biosphere. Abstract Only.  

National Technical Information Service (NTIS)

The abundance ratios of the stable isotopes of light elements such as carbon and sulfur can differ between various naturally-occurring chemical compounds. If coexisting compounds have achieved mutual chemical and isotopic equilibrium, then the relative is...

D. J. Desmarais

1989-01-01

454

Dinitrogen Complexes of Sulfur-ligated Iron  

PubMed Central

We report a unique class of dinitrogen complexes of iron featuring sulfur donors in the ancillary ligand. The ligands utilized are related to the recently studied tris(phosphino)silyl ligands, [SiPR3] ([SiPR3] = [(2-R2PC6H4)3Si]; R = Ph, iPr), but have one or two phosphine arms replaced with thioether donors. Depending on the number of phosphine arms replaced, both mononuclear and dinuclear iron complexes with dinitrogen are accessible. These complexes contribute to a desirable class of model complexes that possess both dinitrogen and sulfur ligands in the immediate iron coordination sphere.

Takaoka, Ayumi; Mankad, Neal P.; Peters, Jonas C.

2011-01-01

455

Method of making a sodium sulfur battery  

DOEpatents

A method of making a portion of a sodium sulfur battery is disclosed. The battery portion made is a portion of the container which defines the volume for the cathodic reactant materials which are sulfur and sodium polysulfide materials. The container portion is defined by an outer metal casing with a graphite liner contained therein, the graphite liner having a coating on its internal diameter for sealing off the porosity thereof. The steel outer container and graphite pipe are united by a method which insures that at the operating temperature of the battery, relatively low electrical resistance exists between the two materials because they are in intimate contact with one another. 3 figs.

Elkins, P.E.

1981-09-22

456

CE IGCC Repowering plant sulfuric acid plant. Topical report, June 1993  

SciTech Connect

A goal of the CE IGCC Repowering project is to demonstrate a hot gas clean-up system (HGCU), for the removal of sulfur from the product gas stream exiting the gasifier island. Combustion Engineering, Inc. (ABB CE) intends to use a HGCU developed by General Electric Environmental Services (GEESI). The original design of this system called for the installation of the HGCU, with a conventional cold gas clean-up system included as a full-load operational back-up. Each of these systems removes sulfur compounds and converts them into an acid off-gas. This report deals with the investigation of equipment to treat this off-gas, recovering these sulfur compounds as elemental sulfur, sulfuric acid or some other form. ABB CE contracted ABB Lummus Crest Inc. (ABB LCI) to perform an engineering evaluation to compare several such process options. This study concluded that the installation of a sulfuric acid plant represented the best option from both a technical and economic point of view. Based on this evaluation, ABB CE specified that a sulfuric acid plant be installed to remove sulfur from off-gas exiling the gas clean-up system. ABB LCI prepared a request for quotation (RFQ) for the construction of a sulfuric acid production plant. Monsanto Enviro-Chem Inc. presented the only proposal, and was eventually selected as the EPC contractor for this system.

Chester, A.M.

1993-12-01

457

Sulfur gas geochemical detection of hydrothermal systems. Final report  

SciTech Connect

The purpose of this investigation was to determine whether a system of exploration using sulfur gases was capable of detecting convecting hydrothermal systems. Three surveying techniques were used at the Roosevelt Hot Springs KGRA in Utah. These were (a) a sniffing technique, capable of instantaneous determinations of sulfur gas concentration, (b) an accumulator technique, capable of integrating the sulfur gas emanations over a 30 day interval, and (c) a method of analyzing the soils for vaporous sulfur compounds. Because of limitations in the sniffer technique, only a limited amount of surveying was done with this method. The accumulator and soil sampling techniques were conducted on a 1000 foot grid at Roosevelt Hot Springs, and each sample site was visited three times during the spring of 1980. Thus, three soil samples and two accumulator samples were collected at each site. The results are shown as averages of three soil and two accumulator determinations of sulfur gas concentrations at each site. Soil surveys and accumulator surveys were conducted at two additional KGRA's which were chosen based on the state of knowledge of these hydrothermal systems and upon their differences from Roosevelt Hot Springs in an effort to show that the exploration metho