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1

Airborne measurements of sulfur dioxide, dimethyl sulfide, carbon disulfide, and carbonyl sulfide by isotope dilution gas chromatography/mass spectrometry  

NASA Technical Reports Server (NTRS)

A gas chromatograph/mass spectrometer is described for determining atmospheric sulfur dioxide, carbon disulfide, dimethyl sulfide, and carbonyl sulfide from aircraft and ship platforms. Isotopically labelled variants of each analyte were used as internal standards to achieve high precision. The lower limit of detection for each species for an integration time of 3 min was 1 pptv for sulfur dioxide and dimethyl sulfide and 0.2 pptv for carbon disulfide and carbonyl sulfide. All four species were simultaneously determined with a sample frequency of one sample per 6 min or greater. When only one or two species were determined, a frequency of one sample per 4 min was achieved. Because a calibration is included in each sample, no separate calibration sequence was needed. Instrument warmup was only a few minutes. The instrument was very robust in field deployments, requiring little maintenance.

Bandy, Alan R.; Thornton, Donald C.; Driedger, Arthur R., III

1993-01-01

2

Monte Carlo predictions of phase equilibria and structure for dimethyl ether + sulfur dioxide and dimethyl ether + carbon dioxide  

NASA Astrophysics Data System (ADS)

A new force field for dimethyl ether (DME) based on the Lennard-Jones (LJ) 12-6 plus point charge functional form is presented in this work. This force field reproduces experimental saturated liquid and vapor densities, vapor pressures, heats of vaporization, and critical properties to within the statistical uncertainty of the combined experimental and simulation measurements for temperatures between the normal boiling and critical point. Critical parameters and normal boiling point are predicted to within 0.1% of experiment. This force field is used in grand canonical histogram reweighting Monte Carlo simulations to predict the pressure composition diagrams for the binary mixtures DME + SO2 at 363.15 K and DME + CO2 at 335.15 and 308.15 K. For the DME + SO2 mixture, simulation is able to qualitatively reproduce the minimum pressure azeotropy observed experimentally for this mixture, but quantitative errors exist, suggesting that multibody effects may be important in this system. For the DME + CO2 mixture, simulation is able to predict the pressure-composition behavior within 1% of experimental data. Simulations in the isobaric-isothermal ensemble are used to determine the microstructure of DME + SO2 and DME + CO2 mixtures. The DME + SO2 shows weak pairing between DME and SO2 molecules, while no specific pairing or aggregation is observed for mixtures of DME + CO2.

Kamath, Ganesh; Ketko, Marybeth; Baker, Gary A.; Potoff, Jeffrey J.

2012-01-01

3

Future Sulfur Dioxide Emissions  

Microsoft Academic Search

The importance of sulfur dioxide emissions for climate change is now established, although substantial uncertainties remain. This paper presents projections for future sulfur dioxide emissions using the MiniCAM integrated assessment model. A new income-based parameterization for future sulfur dioxide emissions controls is developed based on purchasing power parity (PPP) income estimates and historical trends related to the implementation of sulfur

Steven J. Smith; Hugh M. Pitcher; Tom M. Wigley

2005-01-01

4

Sulfur dioxide disposal system  

Microsoft Academic Search

There is disclosed a multi-stage process for reducing sulfur dioxide to sulfur or to hydrogen sulfide whereby a hydrogen-containing gas from a high temperature gasifier is used. In the first stage of the process, the gasifier exit gas is contacted at a minimum temperature of about 1800° F. With recycle gas containing SO2, H2S, COS, mercaptans, and CS2 in order

Kamody

1981-01-01

5

Sulfur Dioxide Detector.  

National Technical Information Service (NTIS)

A composition is provided for detecting the presence of sulfur dioxide by changing color. One type of composition is prepared by mixing a small amount of finely ground potassium permanganate with finely powdered activated silica gel to produce a lilac col...

J. A. Amy H. C. Huber

1980-01-01

6

Sulfur dioxide removal process  

SciTech Connect

A process is described for removing sulfur dioxide from a gas stream with a buffered, aqueous thiosulfate/polythionate solution which comprises: (a) introducing sulfur dioxide-containing gas, recovered hydrogen sulfide, and a buffered, aqueous, lean thiosulfate/polythionate solution to an SO/sub 2/-gas/liquid contacting zone; (b) recovering cleaned gas and a buffered, aqueous, enriched thiosulfate/polythionate solution from the SO/sub 2/-gas/liquid contacting zone; (c) introducing the recovered, enriched solution to a regeneration zone; (d) introducing externally supplied hydrogen sulfide to the regeneration zone to react a portion of the recovered, enriched solution therein to form a slurry of elemental sulfur in a buffered, aqueous, lean thiosulfate/polythionate solution; (e) recovering unreacted excess hydrogen sulfide from the regeneration zone for use in step (a); and (f) withdrawing the slurry from the regeneration zone, separating elemental sulfur from the slurry, and recovering the buffered, aqueous, lean thiosulfate/polythionate solution for use in step (a).

Sliger, A.G.; O'Donnell, J.J.; Northup, A.H. Jr.

1987-01-06

7

Operational overview of the NASA GTE/CITE 3 airborne instrument intercomparisons for sulfur dioxide, hydrogen sulfide, carbonyl sulfide, dimethyl sulfide, and carbon disulfide  

NASA Technical Reports Server (NTRS)

This paper reports the overall experimental design and gives a brief overview of results from the third airborne Chemical Instrumentation Test and Evaluation (CITE 3) mission conducted as part of the National Aeronautics and Space Administration's Global Tropospheric Experiment. The primary objective of CITE 3 was to evaluate the capability of instrumentation for airborne measurements of ambient concentrations of SO2, H2S, CS, dimethyl sulfide, and carbonyl sulfide. Ancillary measurements augmented the intercomparison data in order to address the secondary objective of CITE 3 which was to address specific issues related to the budget and photochemistry of tropospheric sulfur species. The CITE 3 mission was conducted on NASA's Wallops Flight Center Electra aircraft and included a ground-based intercomparison of sulfur standards and intercomparison/sulfur science flights conducted from the NASA Wallops Flight Facility, Wallops Island, Virginia, followed by flights from Natal, Brazil. Including the transit flights, CITE 3 included 16 flights encompassing approximately 96 flight hours.

Hoell, James M., Jr.; Davis, Douglas D.; Gregory, Gerald L.; Mcneal, Robert J.; Bendura, Richard J.; Drewry, Joseph W.; Barrick, John D.; Kirchhoff, Volker W. J. H.; Motta, Adauto G.; Navarro, Roger L.

1993-01-01

8

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...

9

The continuous crystallization of sulfur formed by the liquid-phase reaction of hydrogen sulfide and sulfur dioxide  

Microsoft Academic Search

The crystallization of elemental sulfur is a unit operation in a process being developed to remove hydrogen sulfide from industrial gas streams. The sulfur is formed by the irreversible, liquid-phase reaction of hydrogen sulfide (HâS) and sulfur dioxide (SOâ). Low-temperature sulfur solubility data in triethylene glycol dimethyl ether (Triglyme) and diethylene glycol methyl ether (DGM) were collected. The effects of

C. A. Stevens; S. Lynn

1989-01-01

10

Theoretical and experimental studies of the spin trapping of inorganic radicals by 5,5-dimethyl-1-pyrroline N-oxide (DMPO). 3. Sulfur dioxide, sulfite, and sulfate radical anions.  

PubMed

Radical forms of sulfur dioxide (SO(2)), sulfite (SO(3)(2-)), sulfate (SO(4)(2-)), and their conjugate acids are known to be generated in vivo through various chemical and biochemical pathways. Oxides of sulfur are environmentally pervasive compounds and are associated with a number of health problems. There is growing evidence that their toxicity may be mediated by their radical forms. Electron paramagnetic resonance (EPR) spin trapping using the commonly used spin trap, 5,5-dimethyl-1-pyrroline N-oxide (DMPO), has been employed in the detection of SO(3)(•-) and SO(4)(•-). The thermochemistries of SO(2)(•-), SO(3)(•-), SO(4)(•-), and their respective conjugate acids addition to DMPO were predicted using density functional theory (DFT) at the PCM/B3LYP/6-31+G**//B3LYP/6-31G* level. No spin adduct was observed for SO(2)(•-) by EPR, but an S-centered adduct was observed for SO(3)(•-)and an O-centered adduct for SO(4)(•-). Determination of adducts as S- or O-centered was made via comparison based on qualitative trends of experimental hfcc's with theoretical values. The thermodynamics of the nonradical addition of SO(3)(2-) and HSO(3)(-) to DMPO followed by conversion to the corresponding radical adduct via the Forrester-Hepburn mechanism was also calculated. Adduct acidities and decomposition pathways were investigated as well, including an EPR experiment using H(2)(17)O to determine the site of hydrolysis of O-centered adducts. The mode of radical addition to DMPO is predicted to be governed by several factors, including spin population density, and geometries stabilized by hydrogen bonds. The thermodynamic data supports evidence for the radical addition pathway over the nucleophilic addition mechanism. PMID:22668066

Zamora, Pedro L; Villamena, Frederick A

2012-07-01

11

Effects of aqueous sulfur dioxide on cellulose  

Microsoft Academic Search

The reaction of aqueous sulfur dioxide with cellulose pulp and cotton linters was investigated to determine the effect of this lignocellulosic pretreatment method on the cellulosic portion. Sulfur dioxide treatment dramatically reduced the DP of the cellulose but did not affect its enzymatic digestibility, and did not decrystallize the cellulose as recently reported by Leeet al. (1979).

Anthony H. Conner

1980-01-01

12

Catalyst for the reduction of sulfur dioxide to elemental sulfur  

DOEpatents

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

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

1996-01-01

13

Sulfur Dioxide: Its Role in Climate Change  

NSDL National Science Digital Library

Sulfur dioxide comes from both anthropogenic (related to human activities) and natural sources. Burning coal and other fossil fuels is the largest source of sulfur dioxide from human activities. Students have a choice of analyzing the impact of volcanoesâ emissions of sulfur dioxide on the environment; they can also investigate injecting sulfates into the atmosphere to counteract global warming. Instructions to access NASA data are provided along with additional resources and activities. Suggested grades 7-12. This module was developed to be used in the Earth System Science Education Alliance (ESSEA) courses for middle and high school teachers and is also available to teachers to adapt for general classroom use.

14

Catalyst for the reduction of sulfur dioxide to elemental sulfur  

DOEpatents

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

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

1996-02-27

15

Exposure to Hydrogen Sulfide, Mercaptans and Sulfur Dioxide in Pulp Industry  

Microsoft Academic Search

An hygienic survey for hydrogen sulfide, methyl mercaptan and its derivatives and sulfur dioxide in kraft mills and in sulfite mills revealed concentrations varying from 0 to 20?ppm hydrogen sulfide, 0 to 15?ppm methyl mercaptan and comparable amounts of dimethyl sulfide with dimethyl disulfide up to 1.5?ppm. The greatest emissions were detected at chip chutes and evaporation vacuum pumps. Batch

J. KANGAS; P. JÄPPINEN; H. SAVOLAINEN

1984-01-01

16

Adsorption of sulfur dioxide by native clinoptilolite  

SciTech Connect

The purpose of the present work was to study the adsorption capacity of the little-studied native clinoptilolite from Beregovo in the Zakarpatskaya region (Ruthenia) for sulfur dioxide. Adsorption of SO/sub 2/ under analogous conditions by Patrick's silica gel, prepared by us by a known method, was studied for comparison. Results indicated that native clinoptilolite studied has much higher adsorption capacity than Patrick's silica gel for sulfur dioxide in the temperature range studied. The adsorption capacity of this zeolite alters little with increase of temperature in the range 25-75/sup 0/. It is considered that native clinoptilolite can be used for removing sulfur dioxide from waste gases in the temperature and pressure ranges studied.

Merkun, I.I.; Kel'tsev, N.V.; Bratchuk, F.N.; Rogovik, M.I.

1982-11-10

17

Removal of sulfur dioxide from gas  

Microsoft Academic Search

Emission gas to be scrubbed of sulfur dioxide or the like has turbulent lengthwise flow through an elongated mixing vessel. At a mixing zone in the vessel, near where said gas enters it, finely comminuted lime (Blaine number preferably 6000 before calcining) is fed into the gas and carried out of the vessel with the gas to a cyclone separator.

Dilworth

1981-01-01

18

RETENTION OF SULFUR DIOXIDE BY NYLON FILTERS  

EPA Science Inventory

Based on laboratory studies, recovery efficiencies of sulfur dioxide (SO2) were determined for nylon filters. The nylon filters used in these experiments were found to retain SO2. A relatively uniform amount (1.7%) was recoverable from each nylon filter, independent of relative...

19

Fly Ash Zeolites as Sulfur Dioxide Adsorbents  

Microsoft Academic Search

Air protection technologies generate massive amounts of solid wastes, including fly ash (FA). Zeolite synthesis from FA seems to be an effective method for FA utilization. In addition, fly ash zeolites (FAZs) could be used for sulfur dioxide (SO2) adsorption. Since there is a lack of sufficient information about SO2 uptake on FAZs, we investigated this phenomenon in detail. Two

T. T. Suchecki; T. Wa?ek; M. Banasik

20

SOLID SORBENT FOR COLLECTING ATMOSPHERIC SULFUR DIOXIDE  

EPA Science Inventory

A solid sorbent for collecting atmospheric SO2 was evaluated as part of an overall effort to develop a replacement method for the West-Gaeke method presently used to measure 24-hour ambient sulfur dioxide concentrations in ambient air. Research showed that a solid sorbent, consis...

21

LABORATORY MEASUREMENT OF SULFUR DIOXIDE DEPOSITION VELOCITIES  

EPA Science Inventory

Measurements of sulfur dioxide deposition velocities have been carried out in the laboratory with the use of a cylindrical flow reaction. Analysis of data from these experiments was performed with models that specifically account for diffusive transport in the system. Consequentl...

22

Distribution of Sulfur Dioxide Frost on Io  

NASA Technical Reports Server (NTRS)

Sulfur dioxide, normally a gas at room temperatures, is known to exist on Io's surface as a frost, condensing there from the hot gases emanating from the Io volcanoes. However, the deposition patterns and relation of the frost distribution to the volcanic activity is unknown, since prior measurements lacked the spatial resolution to accurately map the surface frost.

The Galileo Near Infrared Mapping Spectrometer (NIMS) obtained relatively high spatial and spectral resolution images during the C3 orbit, and the characteristic infrared absorptions of sulfur dioxide frost appearing in the spectra were used to produce the SO2 frost map shown on the right. The comparison image on the left (from 1979 Voyager measurements) shows the same view and indicates the surface brightness as seen in visible light.

The frost map shows maximum SO2 concentration as white, lesser amounts as blue coloration, and areas with little or no SO2 as black. The resolution of this map is about 120 km (75 miles), which spans the latitude range 120 W to 270 W.

It is interesting to compare this frost distribution with regions of volcanic activity. Volcanic hotspots identified from NIMS and SSI images occur in many of the dark - low SO2 - areas, a reasonable finding since sulfur dioxide would not condense on such hot regions. The Pele region (to the lower left), N. Colchis hot spots (upper center) and S. Volund (upper right) are good examples of hot spot areas depleted in sulfur dioxide. Much of the rest of this hemisphere of Io has varying amounts of sulfur dioxide present. The most sulfur dioxide-rich area is Colchis Regio, the white area to the right of center.

Of particular interest is the dark area to the south of Colchis Regio. From the study of other NIMS images, it is seen that this region does not have any large, obvious hotspots. However, it is depleted in sulfur dioxide.

The Jet Propulsion Laboratory, Pasadena, CA manages the mission for NASA's Office of Space Science, Washington, DC.

The Jet Propulsion Laboratory, Pasadena, CA manages the mission for NASA's Office of Space Science, Washington, DC.

This image and other images and data received from Galileo are posted on the World Wide Web, on the Galileo mission home page at URL http://galileo.jpl.nasa.gov.

1997-01-01

23

Anthropogenic sulfur dioxide emissions: 1850-2005  

SciTech Connect

Sulfur aerosols impact human health, ecosystems, agriculture, and global and regional climate. A new annual estimate of anthropogenic global and regional sulfur dioxide emissions has been constructed spanning the period 1850 2005 using a bottom-up mass balance method, calibrated to country-level inventory data. Global emissions peaked in the early 1970s and decreased until 2000, with an increase in recent years due to increased emissions in China, international shipping, and developing countries in general. An uncertainty analysis was conducted including both random and systemic uncertainties. The overall global uncertainty in sulfur dioxide emissions is relatively small, but regional uncertainties ranged up to 30%. The largest contributors to uncertainty at present are emissions from China and international shipping. Emissions were distributed on a 0.5 grid by sector for use in coordinated climate model experiments.

Smith, S. J. [Joint Global Change Research Institute, PNNL; Van Aardenne, J. [European Commission Joint Research Centre; Klimont, Z. [International Institute for Applied Systems Analysis; Andres, Robert Joseph [ORNL; Volke, A. [European Environment Agency, Kongens Nytorv 6, 1050 Copenhagen K, Denmark; Delgado Arias, S [Joint Global Change Research Institute (JGCRI)

2011-01-01

24

Anthropogenic Sulfur Dioxide Emissions: 1850-2005  

SciTech Connect

Sulfur aerosols impact human health, ecosystems, agriculture, and global and regional climate. A new annual estimate of anthropogenic global and regional sulfur dioxide emissions has been constructed spanning the period 1850 - 2005. A combination of mass balance and best available inventory data was used in order to achieve the most accurate estimate possible. Global emissions peaked in the early 1970s and decreased until 2000, with an increase in recent years due to increased emissions in China, international shipping, and developing countries in general. An uncertainty analysis was conducted including both random and systemic uncertainties. The overall global uncertainty in sulfur dioxide emissions is relatively small, but regional uncertainties of up to 30% were found. The largest contributors to uncertainty at present are emissions from China and international shipping.

Smith, Steven J.; van Aardenne, John; Klimont, Z.; Andres, Robert; Volke, April C.; Delgado Arias, Sabrina

2011-01-02

25

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

Code of Federal Regulations, 2011 CFR

...sulfur dioxide from any stack at this facility in excess of 0.50 pound of sulfur dioxide per million BTU actual heat input...steam-generating unit B001 located at plant I. (B) 0.50 pound of sulfur dioxide per million BTU actual heat...

2011-07-01

26

Sulfur Dioxide Emissions from Congo Volcanoes  

NASA Technical Reports Server (NTRS)

The Earth Probe Total Ozone Mapping Spectrometer (TOMS) detected a sulfur dioxide cloud associated with the January 2002 eruption of Nyiragongo as it flew over the region at around 11 a.m. local time (0900 UTC) on January 17. The sensor detected no significant amounts of ash in the eruption cloud. At the time of the TOMS overpass the cloud extended up to roughly 200 km (124 miles) northwest of Nyiragongo and was still attached to the volcano. This observation is consistent with nearly coincident MODIS imagery which shows an opaque cloud of gas and steam in the same location. The TOMS measurements show that the amount of sulfur dioxide in the Nyiragongo's plume range from about 10 to 30 kilotons. Please note that TOMS mass retrievals are dependent on the altitude of the cloud and may be adjusted as more information becomes available. Since the cloud may still have been developing at the time of the TOMS overpass, the final sulfur dioxide burden may have been greater. Wind trajectory data (courtesy of Leslie Lait, SSAI) suggest that part of the cloud may have reached at least mid- to upper-tropospheric altitudes of up to 12 km (7 miles), but scientists suspect no significant stratospheric injection of sulfur dioxide as a result of this eruption since the gas was not visible over the Democratic Republic of the Congo region in subsequent TOMS data acquired on January 18. Production of sulfur dioxide without a significant ash cloud is commonly observed during effusive eruptions such as the Nyiragongo event. Although dense low-level ash may be produced during such eruptions, these particulates usually fall out fairly quickly and elude detection by satellite. The size of the January 17 Nyiragongo cloud and the estimated sulfur dioxide tonnage are fairly modest, and at least an order of magnitude smaller than values typically measured by TOMS during eruptions of nearby Nyamuragira during its frequent outbursts (e.g., on February 6, 2001). Sulfur dioxide column amounts (measured in Dobson Units) are much higher in the more extensive Nyamuragira cloud, which contained roughly 420 kilotons of sulfur dioxide. Although several factors could affect the size of the observed cloud in each case-such as the delay between the onset of the eruption and the TOMS overpass, and the volume of lava emitted and the lava composition-the TOMS data suggest that the Nyiragongo magma may have been largely degassed before eruption. One possible mechanism by which this could be achieved is the cyclic degassing of magma in the subaerial lava lakes that have been intermittently present in Nyiragongo's summit crater over the past few decades. Images courtesy Simon Cairn, TOMS Volcanic Emissions Group, Joint Center for Earth Systems Technology, University of Maryland-Baltimore County

2002-01-01

27

Advanced rechargeable lithium sulfur dioxide cell  

Microsoft Academic Search

The electrochemical performance and safety of the rechargeable lithium sulfur dioxide system has been investigated in laboratory cells and in high rate D cells. Small design and active materials were optimized to that cathode utilization of 1.6Ah\\/grams of carbon and 0.19Ah\\/cm3 of cathode were achieved with 100-200 cycles. Discharge and charge of cells at temperatures down to -30 C were

R. C. McDonald; P. Harris; F. Goebel; S. Hossain; R. Vierra

1991-01-01

28

Sulfur Dioxide Inhibition of Photosynthesis in Isolated Spinach Chloroplasts  

PubMed Central

Photosynthetic oxygen evolution by isolated spinach (Spinacia oleracea L.) chloroplasts approached complete inhibition in the presence of a 5 mm concentration of sulfur dioxide. A similar inhibition was observed in the presence of equimolar concentrations of bisulfite ions, suggesting a parallel mode of action. In contrast, an equimolar concentration of sulfite ions was markedly less inhibitory and sulfate ions caused negligible inhibition of apparent photosynthesis. The mode of action of sulfur dioxide and related sulfur anions in inhibiting photosynthesis was found to be essentially independent of direct hydrogen-ion effects. Supplements of inorganic pyrophosphate lessened the inhibition of oxygen evolution caused by sulfur dioxide and the sulfur anions. Sulfur dioxide and the sulfur anions were almost equally effective in inhibiting cyclic and noncyclic photophosphorylation in chloroplast suspensions. However, the extent of the inhibition of these photosynthetic reactions does not appear sufficient to account for the inhibition of photosynthetic oxygen evolution by sulfur dioxide.

Silvius, John E.; Ingle, Morris; Baer, Charles H.

1975-01-01

29

40 CFR 60.333 - Standard for sulfur dioxide.  

Code of Federal Regulations, 2013 CFR

...Standards of Performance for Stationary Gas Turbines § 60.333 Standard for sulfur dioxide...the atmosphere from any stationary gas turbine any gases which contain sulfur dioxide...subpart shall burn in any stationary gas turbine any fuel which contains total sulfur...

2013-07-01

30

40 CFR 60.173 - Standard for sulfur dioxide.  

Code of Federal Regulations, 2013 CFR

...NEW STATIONARY SOURCES Standards of Performance for Primary Zinc Smelters § 60.173 Standard for sulfur dioxide. ...more than 10 percent of the sulfur initially contained in the zinc sulfide ore concentrates will be considered as a roaster...

2013-07-01

31

Kinetics of decomposition of manganese slimes by sulfur dioxide  

SciTech Connect

Lean manganese ores, and slimes obtained during mechanical beneficiation of Chiatura manganese ores, have been treated by the sulfite process, by saturation of suspensions with sulfur dioxide. The kinetics of saturation of the suspensions with sulfur dioxide, and transfer of manganese into solution was studied. Manganese was leached out by passing sulfur dioxide through the slime suspension. The sulfur dioxide dissolved in water to form the weakly dissociated sulfurous acid in equilibrium with its anhydrides. The leaching was conducted without access of air at room temperature. An equation for determination of the rate of sulfur dioxide adsorption by a manganese-containing slurry and for calculation of the degree of manganese extraction into solution was developed from the experimental results. The reaction order and the control regime of the processes were determined.

Dzhaparidze, P.I.; Kelbakiani, N.V.

1982-02-20

32

40 CFR 60.82 - Standard for sulfur dioxide.  

Code of Federal Regulations, 2013 CFR

...STATIONARY SOURCES Standards of Performance for Sulfuric Acid Plants § 60.82 Standard for sulfur dioxide...dioxide in excess of 2 kg per metric ton of acid produced (4 lb per ton), the production being expressed as 100 percent H2 SO4...

2013-07-01

33

Comparative uptake of sulfur in sulfur dioxide and acid rain by corn (Zea mays L. )  

SciTech Connect

This study has compared and evaluated the absorption and accumulation of sulfur from the two major forms of sulfur pollution (sulfur dioxide and sulfur containing acid rain), by seedlings of corn (Zea mays L.). Plants were exposed to matched treatments containing equivalent ..mu..moles S/treatment in sulfur dioxide or simulated acid rain containing sulfuric acid. Pollution levels were chosen to represent low, medium and high ambient pollutant concentrations (0.13, 1.3 and 130.0 ..mu..moles S/treatment). The uptake and distribution of sulfur by plants was followed by using radioactively labelled sulfur (35-S) in both pollutants. Plants were exposed to the pollutants via a single injection of sulfur dioxide or by rainfall simulators with acid rain treatments. From the sulfur dioxide concentrations evaluated (0.67; 1.00; 2.60; 6.70; and 16 ppm), maximum absorption occurred at the highest concentration while sulfur was more efficiently absorbed at lower concentrations. Absorption of sulfur by plants exposed to acid rain (pH 5.4; 4.4; 3.4; and 2.6) was higher with high sulfur/low pH treatments. pH per se, was not responsible for increased sulfur absorption at low pH treatments. Of the total sulfur associated with the plant following exposure to sulfur dioxide and acid rain, 55% and 97%, respectively was not absorbed, and could be released after one minute of a foliar wash. At each equivalent concentration of sulfur, corn seedlings absorbed significantly greater amounts of sulfur from sulfur dioxide than from acid rain.

Simon, J.E.

1984-01-01

34

DYNAMIC DILUTION SYSTEM FOR AUDITING AMBIENT SULFUR DIOXIDE ANALYZERS  

EPA Science Inventory

This paper discusses the development, evaluation, and field performance of a device designed to provide accurate sulfur dioxide concentration standards suitable for auditing the accuracy of continuous, ambient SO2 monitors. This compact, lightweight, device has been subjected to ...

35

Sulfur Dioxide emission from Mt Pinatubo Eruption June 1991  

NSDL National Science Digital Library

This animation shows sulfur dioxide in the stratosphere during the Mt. Pinatubo Eruption and for a few weeks after the eruption. Stratospheric SO2 dissipates rather quickly compared to volcanic ash and stratoshperic H2SO4

Perkins, Lori; Mcpeters, Richard; Herman, Jay

2001-06-12

36

Effects of Sulfur Dioxide on Stomatic Movements in Plants.  

National Technical Information Service (NTIS)

Observations made at sites of pollution strongly indicate a protective role for stomata against the effects of atmospheric sulfur dioxide on vegetation. To confirm this hypothesis, we constructed equipment for exposing a single leaf to atmospheres contain...

J. Bonte L. de Cornis

1973-01-01

37

40 CFR 60.183 - Standard for sulfur dioxide.  

Code of Federal Regulations, 2013 CFR

...operator subject to the provisions of this subpart shall cause to be discharged into the atmosphere from any sintering machine, electric smelting furnace, or converter gases which contain sulfur dioxide in excess of 0.065 percent by volume....

2013-07-01

38

CATALYST EVALUATION FOR A SULFUR DIOXIDE-DEPOLARIZED ELECTROLYZER  

SciTech Connect

Thermochemical processes are being developed to provide global-scale quantities of hydrogen. A variant on sulfur-based thermochemical cycles is the Hybrid Sulfur (HyS) Process which uses a sulfur dioxide depolarized electrolyzer (SDE) to produce the hydrogen. Testing examined the activity and stability of platinum and palladium as the electrocatalyst for the SDE in sulfuric acid solutions. Cyclic and linear sweep voltammetry revealed that platinum provided better catalytic activity with much lower potentials and higher currents than palladium. Testing also showed that the catalyst activity is strongly influenced by the concentration of the sulfuric acid electrolyte.

Hobbs, D; Hector Colon-Mercado, H

2007-01-31

39

Sulfur dioxide absorption at DF laser wavelengths  

NASA Astrophysics Data System (ADS)

The absorption of DF laser lines by sulfur dioxide under atmospheric conditions is measured in light of the possible application of optical methods to the detection of the atmospheric pollutant. Absorption measurements were performed for 20 DF laser wavelengths between 2792 and 2509 kaysers in a multipass absorption cell. Weak absorption is detected around a wavelength of 3.7 microns and is attributed to the 2 nu 3 band of SO2. The P 4(6) line at 3.9843 microns is found to be strongly absorbed by the (nu 1 + nu 3) band of SO2, with a specific absorption coefficient of 0.44 + or - 0.01/cm per atm, which indicates that strong SO2 emissions in the atmosphere can be detected optically. Measurements of the pressure dependence of the absorption coefficient of the P4(6) line reveal broadening coefficients between 1.5 and 5 MHz/Torr, depending on line strength, and a wavenumber difference of 0.0043 + or - 0.0004 kaysers from the P4(6) DF line to the center of the nearest SO2 line.

Altmann, J.; Pokrowsky, P.

1980-10-01

40

Sulfur dioxide emission control in Japanese copper smelters. Information circular  

Microsoft Academic Search

Japanese copper smelters mostly are located in areas of concentrated industrial activity and high levels of atmospheric pollution. A review of unofficial sulfur dioxide emission control data from major Japanese smelters show capture of 91 to 99.7 percent of the sulfur in the smelter feed. The bulk of Japanese smelting capacity was constructed in the last 10 years. Six of

J. B. Rosenbaum; M. Hayashi; G. M. Potter

1976-01-01

41

Carbon dioxide tolerance in the single-stage liquid-phase synthesis of dimethyl ether  

SciTech Connect

In the liquid-phase dimethyl ether process, methanol synthesis catalyst (Cu/ZnO/Al{sub 2}O{sub 3}) and methanol dehydration catalyst ({gamma}-alumina) are slurred in an inert liquid medium. The inert liquid medium used in this investigation is a white mineral oil, Witco-40. This multiphase reaction is conducted in a mechanically agitated slurry reactor. In this process, syngas conversion can be significantly improved by coproduction of dimethyl ether along with methanol. The coproduction strategy improves the thermodynamic and kinetic environment of the reaction system. The effects of catalyst loadings in the slurry and the roles played by carbon dioxide in dimethyl ether synthesis were studied by conducting kinetic experiments. The liquid-phase dimethyl ether synthesis process exhibits higher carbon dioxide tolerance as compared to the liquid-phase methanol synthesis process, whose optimal carbon dioxide concentration in the unbalanced syngas feed is around 8%. These results have been experimentally confirmed.

Sardesai, A.; Gunda, A.; Tartamella, T.; Lee, S.

2000-01-01

42

Non aqueous electrolytes for lithium-sulfur dioxide batteries  

SciTech Connect

Mixed organic solvent systems are of considerable interest for use in high energy density batteries. It has been observed that with a proper choice of solvents, one can achieve a drastic increase in cell performance-related properties such as dielectric constant, conductance, and viscosity. This paper presents a detailed investigation of the scope of mixed solvent systems with N-methyl pyrrolidinone (NMP) as the common solvent. Physical and thermodynamic properties such as density, viscosity, excess volume, and phase equilibria of mixed solvent systems with sulfur dioxide are studied, with a view to improving the performance and safety aspects of lithium/sulfur dioxide batteries.

Anantaraman, A.V.; Gardiner, C.L.

1983-10-01

43

Process for sequestering carbon dioxide and sulfur dioxide  

DOEpatents

A process for sequestering carbon dioxide, which includes reacting a silicate based material with an acid to form a suspension, and combining the suspension with carbon dioxide to create active carbonation of the silicate-based material, and thereafter producing a metal salt, silica and regenerating the acid in the liquid phase of the suspension.

Maroto-Valer, M. Mercedes (State College, PA); Zhang, Yinzhi (State College, PA); Kuchta, Matthew E. (State College, PA); Andresen, John M. (State College, PA); Fauth, Dan J. (Pittsburgh, PA)

2009-10-20

44

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

45

Fate of air pollutants: removal of ethylene, sulfur dioxide, and nitrogen dioxide by soil  

Microsoft Academic Search

The ultimate sink for many air pollutants is unknown. Data are presented here in support of the idea that reaction with soil, through microbial or chemical means, can remove ethylene, other hydrocarbons, sulfur dioxide, and nitrogen dioxide from the air. 5 references, 1 figure, 1 table.

F. B. Abeles; L. E. Craker; L. E. Forrence; G. R. Leather

1971-01-01

46

Quantitative Gas Analysis of Sulfur Dioxide in Nitrogen by Fourier Transform Infrared Spectrophotometer.  

National Technical Information Service (NTIS)

A method for quantitative gas analysis of sulfur dioxide contained in nitrogen using the Fourier transform infrared spectrophotometer has been established. On account of the strong adsorption properties of sulfur dioxide, the measuring method adopted is o...

Y. Koga M. Sugie S. Kondo S. Saeki

1979-01-01

47

Interaction of sulfur dioxide with 1-benzyl-1,4-dihydronicotinamide  

SciTech Connect

Anhydrous sulfur dioxide reacts rapidly with 1-benzyl-1,4-dihydronicotinamide to give a reduced species of sulfur dioxide, possibly HSO/sub 2//sup -/, which can be trapped by reaction with Michael acceptors to give sulfones.

Jarvis, W.F.; Dittmer, D.C.

1983-08-12

48

75 FR 81555 - Approval and Promulgation of Air Quality Implementation Plans; Minnesota; Sulfur Dioxide SIP...  

Federal Register 2010, 2011, 2012, 2013

...Implementation Plans; Minnesota; Sulfur Dioxide SIP Revision for Marathon Petroleum St. Paul Park AGENCY: Environmental Protection...sulfur dioxide State Implementation Plan revision request for Marathon Petroleum in St. Paul Park, Minnesota. This submittal...

2010-12-28

49

SUSCEPTIBILITY OF WOODY PLANTS TO SULFUR DIOXIDE AND PHOTOCHEMICAL OXIDANTS  

EPA Science Inventory

This report presents the result of a detailed review of European and United States literature regarding the sensitivity of woody vegetation to sulfur dioxide, ozone, peroxyacetyl nitrate (PAN), or nitrogen oxides. Reference is made to Russian, Japanese and Austrian literature onl...

50

Selected Studies on Alkaline Additives. Sulfur Dioxide Control.  

National Technical Information Service (NTIS)

Concentrated on limestone-sulfur dioxide (SO2) reactions, alkaline additives research has defined the kinetics and capacity as well as the effects of overburning. The kinetics of SO2 sorption by limestone calcines has been determined with a high temperatu...

R. H. Borgwardt D. C. Drehmel T. A. Kittleman D. R. Mayfield J. S. Bowen

1971-01-01

51

Process for removing sulfur dioxide from flue gases  

Microsoft Academic Search

This patent describes an improvement in a dry process for the removal of sulfur dioxide from flue gases by the addition thereto of hydrated lime containing sugar in a coal combustion unit, wherein the flue gases result from the combustion of a coal in a combustion chamber, and the flue gases are treated in an electrostatic precipitator prior to discharge

M. W. Jr

1989-01-01

52

SULFUR DIOXIDE SOURCES IN CLASS I WILDERNESS AREAS, WA  

EPA Science Inventory

This map shows industrial plants which emit sulfur dioxide (SO2) in the state of Washington. Different plot symbols are used for sources which emit less than 100 tons/year, between 100 and 1000 tons/year, and over 1000 tons/year of SO2. The SO2 sources are plotted on a background...

53

SULFUR DIOXIDE SOURCES IN WA, OR, AND ID  

EPA Science Inventory

This map shows industrial plants which emit 100 tons/year or more of sulfur dioxide (SO2) in Idaho, Oregon, and Washington. 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: USGS, Nat...

54

LIGNOSULFONATE-MODIFIED CALCIUM HYDROXIDE FOR SULFUR DIOXIDE CONTROL  

EPA Science Inventory

The article discusses the use of lignosulfonate-modified calcium hydroxide Ca(OH)2 for sulfur dioxide (SO2) control. The limestone injection multistage burner (LIMB) process is currently being developed at the U.S. EPA as a low cost retrofittable technology for controlling oxides...

55

Sulfur dioxide removal from flue gases with sulfite oxidation inhibition  

SciTech Connect

This paper discusses an improvement in a method for removal of sulfur dioxide from flue gases in a wet scrubber, wherein an aqueous alkaline earth metal component slurry is contacted in the wet scrubber with the flue gases and the slurry after the contact, containing sulfites and bisulfites, is passed to a recycle tank from which a portion thereof is discharged while the remainder is recycled to the wet scrubber. The improvement comprises: forming a mixture of calcium thiosulfate and calcium polysulfides by reaction of lime and emulsified sulfur; adding the mixture so formed to the recycle tank for reaction with the sulfites and bisulfites in the slurry so as to produce thiosulfates from the calcium polysulfides and provide 0.5 to 20 millimoles of thiosulfate per liter of liquid contained in the wet scrubber; and recycling the slurry from the recycle tank to the wet scrubber to remove sulfur dioxide from the flue gases.

Lee, Y.J.; Benson, L.B.; College, J.W.

1990-12-11

56

Historical Sulfur Dioxide Emissions 1850-2000: Methods and Results  

SciTech Connect

A global, self-consistent estimate of sulfur dioxide emissions over the last one and a half century were estimated by using a combination of bottom-up and best available inventory methods including all anthropogenic sources. We find that global sulfur dioxide emissions peaked about 1980 and have generally declined since this time. Emissions were extrapolated to a 1{sup o} x 1{sup o} grid for the time period 1850-2000 at annual resolution with two emission height levels and by season. Emissions are somewhat higher in the recent past in this new work as compared with some comprehensive estimates. This difference is largely due to our use of emissions factors that vary with time to account for sulfur removals from fossil fuels and industrial smelting processes.

Smith, Steven J.; Andres, Robert; Conception , Elvira; Lurz, Joshua

2004-01-25

57

Collaborative Study of Method for the Determination of Sulfuric Acid Mist and Sulfur Dioxide Emissions from Stationary Sources.  

National Technical Information Service (NTIS)

Statistical analyses are performed on data obtained in collaborative testing of EPA Method 8 (Determination of Sulfuric Acid Mist and Sulfur Dioxide Emissions From Stationary Sources) and from ancillary tests performed in conjunction with the analysis of ...

D. E. Camann H. F. Hamil R. E. Thomas

1974-01-01

58

Biofilm control studies using ferrate and sulfur dioxide. Final report  

SciTech Connect

This study evaluates the possibility of utilizing two new compounds for biofilm control. The two compounds studied were iron (VI) ferrate and sulfur dioxide. Previous studies have indicated that iron (VI) ferrate is an effective disinfectant of bacterial suspensions. Therefore, the possibility of ferrate inactivating bacterial film was studied in test laboratory condensers. Bench scale flow through systems were established and environmental conditions were set so that a bacterial film of greater than 100 microns developed in less than two weeks operation. The effectiveness of ferrate treatment for biofouling control was ascertained by measuring film thickness vs. time in the test systems as a function of various ferrate doses. For ferrate concentrations similar to those effective in suspended systems, that is, 10/sup -5/M ferrate, good biofilm growth prevention was observed. When ferrate concentrations were decreased to below 10/sup -6/M, no repression of film growth was observed. Therefore, ferrate is a possible control chemical for biofilm growth prevention in condenser systems. The second part of this study dealt with the evaluation of sulfur dioxide as a biocidal agent. This study was only preliminary in nature and the main objective was to determine whether sulfur dioxide could act as a biocide against suspended bacterial systems. No biofilm studies were undertaken using SO/sub 2/ as a treatment chemical. The results indicated that sulfur dioxide is an effective biocide but its effectiveness is highly pH dependent. Several different types of bacterial were used as test organisms and all were rapidly inactivated at reasonable sulfur dioxide concentrations when the pH was below four. For neutral or basic pH very large SO/sub 2/ concentrations, often approaching two grams per liter, were required for reasonable disinfection kinetics. 65 references, 35 figures, 6 tables.

Waite, T.D.

1984-10-01

59

Effects of ozone and sulfur dioxide on soybeans  

SciTech Connect

Ambient ozone concentrations at three rural upper-midwestern sites were characterized based upon four years of continuous monitoring. Examination of annual and diurnal fluctuations and individual events revealed a relationship between ozone and temperature, solar radiation, oxides of nitrogen, and stratospheric incursion. Ambient sulfur dioxide concentrations near a large point source in central Minnesota were characterized based upon four years of monitoring during the summer months. Fumigation events were rare, and the concentrations during the events were low. The mean annual concentration of sulfur dioxide was approximately 0.4 ppB. Soybeans were grown in ambient plots and in open-top field chambers which were either filtered or unfiltered to remove pollutants from the incoming air. The results indicated that the programmed ozone and/or sulfur dioxide treatments did not consistently reduce yield, however, they did cause changes in foliar chlorophyll and sulfur concentrations. The 1980 unfiltered ambient air containing high concentrations of ozone caused a yield reduction of approximately four percent compared to soybeans grown in chambers with filtered air.

Pratt, G.C.

1982-01-01

60

The removal of sulfur dioxide from flue gases  

PubMed Central

The growth of industrialization makes it imperative to reduce the amounts of sulfur dioxide emitted into the atmosphere. This article describes various processes for cleaning flue gases, and gives details of new methods being investigated. Wet scrubbing with water, though widely practised, has many disadvantages. Scrubbing with zinc oxide, feasible in zinc works, is more satisfactory. Dry methods use a solid absorbent; they have the advantage of a high emission temperature. Other methods are based on the addition to the fuel or the flue gases of substances such as activated metal oxides, which react with the sulfur to form compounds less harmful than sulfur dioxide. Also being investigated are a two-stage combustion system, in which the sulfur dioxide is removed in the first stage, and the injection of activated powdered dolomite into burning fuel; the resulting sulfates being removed by electrostatic precipitation. A wet catalysis process has recently been developed. Most of the cleaning processes are not yet technically mature, but first results show good efficiency and relatively low cost.

Kettner, Helmut

1965-01-01

61

Sulfur–Aromatic Interactions: A Computational Study of the Dimethyl Sulfide–Benzene Complex  

Microsoft Academic Search

To investigate sulfur–aromatic interactions, intermolecular interaction energies between dimethyl sulfide and benzene were computed using ab initio molecular orbital calculations. Inclusion of electron correlation at the MP2 level predicted significantly more stable complexes compared to Hartree–Fock calculations, whereas density functional theory with the B3LYP functional shows no improvement over Hartree–Fock calculations. The molecular mechanics force fields AMBER95 and OPLS-AA were

Julianto Pranata

1997-01-01

62

Catalytic oxidation of sulfur dioxide by heterogeneous cobalt-phthalocyanine  

SciTech Connect

Various homogeneous and hybrid cobalt phthalocyanines were developed. They were shown to be effective catalysts for the catalytic degradation of many aqueous pollutants. The catalytic activity of these systems was attributed to their ability to activate molecular oxygen. Semiconductor titanium dioxide was found to be useful both as solid support and photocatalyst. The electron relay property of cobalt phthalocyanine on the photoactive TiO/sub 2/ surface was elucidated. The homogeneous and heterogeneous kinetics and mechanisms for the catalytic oxidation of aqueous sulfur dioxide were studied.

Hong, P.K.A.

1988-01-01

63

Simultaneous Sulfur Dioxide and Nitrogen Dioxide Removal by Calcium Hydroxide and Calcium Silicate Solids  

Microsoft Academic Search

At conditions typical of a bag filter exposed to a coal-fired flue gas that has been adiabatically cooled with water, calcium hydroxide and calcium silicate solids were exposed to a dilute, humidified gas stream of nitrogen dioxide (NO2) and sulfur dioxide (SO2) in a packed-bed reactor. A prior study found that NO2 reacted readily with surface water of alkaline and

Christopher H. Nelli; Gary T. Rochelle

1998-01-01

64

Resistance to injury by sulfur dioxide  

SciTech Connect

In Cucurbitaceae young leaves are resistant to injury from acute exposure to SO/sub 2/, whereas mature leaves are sensitive. After exposure of cucumber (Cucumis sativus L.) plants to SO/sub 2/ at injurious concentrations, illuminated leaves emit volatile sulfur, which is solely H/sub 2/S. Young leaves emit H/sub 2/S many times more rapidly than do mature leaves. Young leaves convert approximately 10% of absorbed (/sup 35/S)SO/sub 2/ to emitted (/sup 35/S)H/sub 2/S, but mature leaves convert less than 2%. These results suggest that a high capability for the reduction of SO/sub 2/ to H/sub 2/S and emission of the H/sub 2/S is a part of the biochemical basis of the resistance of young leaves to SO/sub 2/.

Sekiya, J.; Wilson, L.G.; Filner, P.

1982-08-01

65

Lagrangian measurements of sulfur dioxide to sulfate conversion rates  

SciTech Connect

On the basis of Project MISTT data and proposed homogeneous gas phase oxidation mechanisms for sulfur dioxide, it has been suggested that the degree of mixing with background air, the chemical composition of the background air, and the intensity of the sunlight available are key factors determining the rate of sulfur dioxide to sulfate conversion. These hypotheses are examined in light of Lagrangian measurements of conversion rates in power plant plumes made during the Tennessee Plume Study and Project Da Vinci. It is found that the Lagrangian conversion rate measurements are consistent with these hypotheses. It has also been suggested that the concentration of ozone may serve as a workable surrogate for the concentrations of the free radicals involved in the homogeneous gas phase mechanism. Certain of the Lagrangian data indicate that this suggestion should be regarded with caution.

Zak, B.D.

1980-01-01

66

Lagrangian measurements of sulfur dioxide to sulfate conversion rates  

SciTech Connect

On the basis of Project MISTT data and proposed homogeneous gas phase oxidation mechanisms for sulfur dioxide, it has been suggested that the degree of mixing with background air, the chemical composition of the background air, and the intensity of the sunlight available are key factors determining the rate of sulfur dioxide to sulfate conversion. These hypotheses are examined in light of Lagrangian measurements of conversion rates in power plant plumes made during the Tennessee Plume Study and Project Da Vinci. It is found that the Lagrangian conversion rate measurements are consistent with these hypotheses. It has also been suggested that the concentration of ozone may serve as a workable surrogate for the concentrations of the free radicals involved in the homogeneous gas phase mechanism. The nighttime Lagrangian data remind one that the gross difference in mean lifetime of ozone and free radicals can lead to situations in which the ozone concentration is not a good surrogate for the free radical concentrations.

Zak, B.D.

1981-05-01

67

Airborne sulfur trace species intercomparison campaign: Sulfur dioxide, dimethylsulfide, hydrogen sulfide, carbon disulfide, and carbonyl sulfide  

NASA Technical Reports Server (NTRS)

Results from an airborne intercomparison of techniques to measure tropospheric levels of sulfur trace gases are presented. The intercomparison was part of the NASA Global Tropospheric Experiment (GTE) and was conducted during the summer of 1989. The intercomparisons were conducted on the Wallops Electra aircraft during flights from Wallops Island, Virginia, and Natal, Brazil. Sulfur measurements intercompared included sulfur dioxide (SO2), dimethylsulfide (DMS), hydrogen sulfide (H2S), carbon disulfide (CS2), and carbonyl sulfide (OCS). Measurement techniques ranged from filter collection systems with post-flight analyses to mass spectrometer and gas chromatograph systems employing various methods for measuring and identifying the sulfur gases during flight. Sampling schedules for the techniques ranged from integrated collections over periods as long as 50 minutes to one- to three-minute samples every ten or fifteen minutes. Several of the techniques provided measurements of more than one sulfur gas. Instruments employing different detection principles were involved in each of the sulfur intercomparisons. Also included in the intercomparison measurement scenario were a host of supporting measurements (i.e., ozone, nitrogen oxides, carbon monoxide, total sulfur, aerosols, etc.) for purposes of: (1) interpreting results (i.e., correlation of any noted instrument disagreement with the chemical composition of the measurement environment); and (2) providing supporting chemical data to meet CITE-3 science objectives of studying ozone/sulfur photochemistry, diurnal cycles, etc. The results of the intercomparison study are briefly discussed.

Gregory, Gerald L.; Hoell, James M., Jr.; Davis, Douglas D.

1991-01-01

68

Benefits and Costs From Sulfur Dioxide Trading: A Distributional Analysis  

Microsoft Academic Search

Prior to the passage of Title IV of the 1990 Clean Air Act Amendments (CAAA), there had been a lively debate involving Congress,\\u000a the U.S. Environmental Protection Agency (EPA), and academics, about the need for reducing sulfur dioxide (SO2) emissions due to the problem of acid rain. In addition to domestic pressure, Canada was putting political pressure on the\\u000a United

Ronald J. Shadbegian; Wayne Gray; Cynthia Morgan

2005-01-01

69

Performance of lithium-sulfur dioxide rechargeable cells  

Microsoft Academic Search

The lithium-sulfur dioxide rechargeable system has been investigated with LiAlCl4 electrolyte in hermetically sealed experimental cells. Over 50 cells were tested at 1-5 mA\\/cm2 discharge and 0.5-2 mA\\/cm2 charge rates using carbon cathode material to evaluate cycle life and capacity at ambient (21°C) and low (-30°C) temperatures. Most of the cells delivered excellent cycle life with significantly higher capacity than

Sohrab Hossain; Peter Harris; Robert McDonald; Franz Goebel

1990-01-01

70

Sulfur dioxide: episodic injection shows evidence for active venus volcanism.  

PubMed

Pioneer Venus ultraviolet spectra from the first 5 years of operation show a decline (by more than a factor of 10) in sulfur dioxide abundance at the cloud tops and in the amount of submicron haze above the clouds. At the time of the Pioneer Venus encounter, the values for both parameters greatly exceeded earlier upper limits. However, Venus had a similar appearance in the late 1950's, implying the episodic injection of sulfur dioxide possibly caused by episodic volcanism. The amount of haze in the Venus middle atmosphere is about ten times that found in Earth's stratosphere after the most recent major volcanic eruptions, and the thermal energy required for this injection on Venus is greater by about an order of magnitude than the largest of these recent Earth eruptions and about as large as the Krakatoa eruption of 1883. The episodic behavior of sulfur dioxide implies that steady-state models of the chemistry and dynamics of cloud-top regions may be of limited use. PMID:17830154

Esposito, L W

1984-03-01

71

Sulfur dioxide - Episodic injection shows evidence for active Venus volcanism  

NASA Astrophysics Data System (ADS)

Pioneer Venus ultraviolet spectra from the first 5 years of operation show a decline (by more than a factor of 10) in sulfur dioxide abundance at the cloud tops and in the amount of submicron haze above the clouds. At the time of the Pioneer Venus encounter, the values for both parameters greatly exceeded earlier upper limits. However, Venus had a similar appearance in the late 1950's, implying the episodic injection of sulfur dioxide possibly caused by episodic volcanism. The amount of haze in the Venus middle atmosphere is about ten times that found in earth's stratosphere after the most recent major volcanic eruptions, and the thermal energy required for this injection on Venus is greater by about an order of magnitude than the largest of these recent earth eruptions and about as large as the Krakatoa eruption of 1883. The episodic behavior of sulfur dioxide implies that steady-state models of the chemistry and dynamics of cloud-top regions may be of limited use.

Esposito, L. W.

1984-03-01

72

Sulfur dioxide - Episodic injection shows evidence for active Venus volcanism  

NASA Technical Reports Server (NTRS)

Pioneer Venus ultraviolet spectra from the first 5 years of operation show a decline (by more than a factor of 10) in sulfur dioxide abundance at the cloud tops and in the amount of submicron haze above the clouds. At the time of the Pioneer Venus encounter, the values for both parameters greatly exceeded earlier upper limits. However, Venus had a similar appearance in the late 1950's, implying the episodic injection of sulfur dioxide possibly caused by episodic volcanism. The amount of haze in the Venus middle atmosphere is about ten times that found in earth's stratosphere after the most recent major volcanic eruptions, and the thermal energy required for this injection on Venus is greater by about an order of magnitude than the largest of these recent earth eruptions and about as large as the Krakatoa eruption of 1883. The episodic behavior of sulfur dioxide implies that steady-state models of the chemistry and dynamics of cloud-top regions may be of limited use.

Esposito, L. W.

1984-01-01

73

SYNTHESIS OF SULFUR-BASED WATER TREATMENT AGENT FROM SULFUR DIOXIDE WASTE STREAMS  

SciTech Connect

We propose a process that uses sulfur dioxide from coal combustion as a raw material to synthesize polymeric ferric sulfate (PFS), a water treatment agent. The process uses sodium chlorate as an oxidant and ferrous sulfate as an absorbent. The major chemical mechanisms in this reaction system include oxidation, hydrolysis, and polymerization. Oxidation determines sulfur conversion efficiency while hydrolysis and polymerization control the quality of product. Many factors, including SO{sub 2} inlet concentration, flow rate of simulated flue gas, reaction temperature, addition rate of oxidant and stirring rate, may affect the efficiencies of SO{sub 2} removal. Currently, the effects of SO{sub 2} inlet concentration, the flow rate of simulated flue gas and addition rate of flue gas on removal efficiencies of SO{sub 2}, are being investigated. Experiments shown in this report have demonstrated that the conversion efficiencies of sulfur dioxide with ferrous sulfate as an absorbent are in the range of 60-80% under the adopted process conditions. However, the conversion efficiency of sulfur dioxide may be improved by optimizing reaction conditions to be investigated. Partial quality indices of the synthesized products, including Fe{sup 2+} concentration and total iron concentration, have been evaluated.

Robert C. Brown; Maohong Fan

2001-12-01

74

The rotational spectrum of protonated sulfur dioxide, HOSO+  

NASA Astrophysics Data System (ADS)

Aims: We report on the millimeter-wave rotational spectrum of protonated sulfur dioxide, HOSO+. Methods: Ten rotational transitions between 186 and 347 GHz have been measured to high accuracy in a negative glow discharge. Results: The present measurements improve the accuracy of the previously reported centimeter-wave spectrum by two orders of magnitude, allowing a frequency calculation of the principal transitions to about 4 km s-1 in equivalent radial velocity near 650 GHz, or one linewidth in hot cores and corinos. Conclusions: Owing to the high abundance of sulfur-bearing molecules in many galactic molecular sources, the HOSO+ ion is an excellent candidate for detection, especially in hot cores and corinos in which SO2 and several positive ions are prominent.

Lattanzi, V.; Gottlieb, C. A.; Thaddeus, P.; Thorwirth, S.; McCarthy, M. C.

2011-09-01

75

Lithium-sulfur dioxide batteries on Mars rovers  

NASA Technical Reports Server (NTRS)

NASA's 2003 Mars Exploration Rover (MER) missions, Spirit and Opportunity, have been performing exciting surface exploration studies for the past six months. These two robotic missions were aimed at examining the presence of water and, thus, any evidence of life, and at understanding the geological conditions of Mars, These rovers have been successfully assisted by primary lithium-sulfur dioxide batteries during the critical entry, descent, and landing (EDL) maneuvers. These batteries were located on the petals of the lander, which, unlike in the Mars Pathfinder mission, was designed only to carry the rover. The selection of the lithium-sulfur dioxide battery system for this application was based on its high specific energy and high rate discharge capability, combined with low heat evolution, as dictated by this application. Lithium-sulfur dioxide batteries exhibit voltage delay, which tends to increase at low discharge temperatures, especially after extended storage at warm temperatures, In the absence of a depassivation circuit, as provided on earlier missions, e.g., Galileo, we were required to depassivate the lander primary batteries in a unique manner. The batteries were brought onto a shunt-regulated bus set at pre-selected discharge voltages, thus affecting depassivation during constant discharge voltages. Several ground tests were preformed, on cells, cell strings and battery assembly with five parallel strings, to identify optimum shunt voltages and durations of depassivation. We also examined the repassivation of lithium anodes, subsequent to depassivation. In this paper, we will describe these studies, in detail, as well as the depassivation of the lander flight batteries on both Spirit and Opportunity rover prior to the EDL sequence and their performance during landing on Mars.

Ratnakumar, Bugga V.; Smart, M. C.; Ewell, R. C.; Whitcanack, L. D.; Kindler, A.; Narayanan, S. R.; Surampudi, S.

2004-01-01

76

Effects of sulfur dioxide on lichen lipids and fatty acids.  

PubMed

Lipids and fatty acids were studied in some lichen species after exposure to 1 ppm of aqueous sulfur dioxide. The changes in lipid composition are specific to the lichen species tested. The exposure of lichens to SO2 resulted in a slight reduction of the total phospholipid content. The amount of betaine lipid diacylglyceryltrimethylhomoserine was increased in Stereocaulon paschale, but the level of this lipid was not changed in Peltigera aphthosa. An increase in fatty acid unsaturation in lichens in response to the effect of SO2 probably has adaptive significance. PMID:9986914

Bychek-Guschina, I A; Kotlova, E R; Heipieper, H

1999-01-01

77

A sensitive method for measuring atmospheric concentrations of sulfur dioxide  

NASA Technical Reports Server (NTRS)

A new method for measuring tropospheric sulfur dioxide concentrations is proposed which is based on the mist chamber sampling method. At the present stage of development, the detection limit of the method is approximately 20 parts per trillion for a 45-min sampling time, with lower concentrations detectable with lower precision. The overall reproducibility of the method (+/-95 percent confidence intervals) is estimated at +/-10 percent. The technique is relatively simple, inexpensive, and lightweight, making it ideally suited for numerous field applications in atmospheric chemistry and biogeochemical studies from both ground-based and airborne platforms.

Klemm, O.; Talbot, R. W.

1991-01-01

78

40 CFR 721.9672 - Amides, tall-oil fatty, N-[2-[2-hydroxyethyl)amino]ethyl], reaction products with sulfur dioxide...  

Code of Federal Regulations, 2010 CFR

...products with sulfur dioxide; fatty acids, tall-oil, reaction products...1-piperazineethanamine and sulfur dioxide; fatty acids, tall-oil reaction products...products with sulfur dioxide; fatty acids, tall-oil, reaction...

2010-07-01

79

40 CFR 721.9672 - Amides, tall-oil fatty, N-[2-[2-hydroxyethyl)amino]ethyl], reaction products with sulfur dioxide...  

Code of Federal Regulations, 2010 CFR

...products with sulfur dioxide; fatty acids, tall-oil, reaction products...1-piperazineethanamine and sulfur dioxide; fatty acids, tall-oil reaction products...products with sulfur dioxide; fatty acids, tall-oil, reaction...

2009-07-01

80

Cathodic reduction of sulfur dioxide in nonaqueous electrolytes. The effect of solution composition on the diffusion coefficient of sulfur dioxide  

SciTech Connect

The authors measured the diffusion coefficients of SO/sub 2/ in electrolytes based on propylene carbonate, acetonitrile, dimethylformamide and dimethylsulfoxide in order to estimate possible diffusion limitations with respect to SO/sub 2/ and to establish the influence exerted by the solvent type on the process. The diffusion coefficients were calculated from the limiting diffusion currents of steady-state polarization curves for sulfur dioxide reduction recorded at a gold microdisk electrode which had a diameter of 2 x 10/sup -3/ cm. In lithium salt solutions the potentiodynamic curves recorded at the microelectrode do not exhibit a limiting current but are characterized by a current maximum.

Shembel, E.M.; Ksenzhek, O.S.; Lituinova, V.I.; Lobach, G.A.

1986-09-01

81

A palladium-catalyzed three-component coupling of arylboronic acids, sulfur dioxide and hydrazines.  

PubMed

A novel and efficient route to aryl N-aminosulfonamides via a palladium-catalyzed three-component coupling of arylboronic acids, sulfur dioxide and hydrazines in the presence of a balloon of dioxygen is reported. The reaction proceeded smoothly under mild conditions and DABCO·(SO(2))(2) was used as the source of sulfur dioxide. PMID:22743613

Ye, Shengqing; Wu, Jie

2012-08-11

82

Process for preparing a sulfur dioxide containing gas stream for reaction with coal  

SciTech Connect

A process is described for preparing a gas stream containing sulfur dioxide and water for reaction with coal to convert the sulfur dioxide to gaseous elemental sulfur. Water is initially removed from the gas stream to increase the percentage of sulfur dioxide in the stream after which the gas stream is passed through the flame of a burner to add combustion gases to the gas stream. Steam is then mixed with the gas stream to increase the percentage of water in the gas stream before it is reacted with the coal.

Raskin, N.R.

1984-10-16

83

Sulfur dioxide capture in the combustion of mixtures of lime, refuse-derived fuel, and coal  

SciTech Connect

Chlorine and sulfur mass balance studies have been carried out in the combustion of mixtures of lime, refuse-derived fuel, and coal in the NIST multikilogram capacity batch combustor. The catalytic effect of manganese dioxide on the trapping of sulfur dioxide by lime was examined. Under our conditions, only 4% of the chlorine was trapped in the ash and no effect of manganese dioxide was observed. Between 42 and 14% of the total sulfur was trapped in the ash, depending upon the lime concentration. The effect of manganese dioxide on sulfur capture was not detectable. The temperature of the ash was estimated to be near 1200{degrees}C, which was in agreement with that calculated from sulfur dioxide capture thermodynamics. 10 refs., 12 figs., 10 tabs.

Churney, K.L.; Buckley, T.J. (National Inst. of Standards and Technology, Gaithersburg, MD (USA). Center for Chemical Technology)

1990-06-01

84

Sulfur dioxide emissions and sulfur deposition from international shipping in Asian waters  

NASA Astrophysics Data System (ADS)

Emissions of sulfur dioxide from international shipping in Asian waters have been estimated using information on typical shipping parameters and quantities of goods shipped to and from the major ports. Emissions are estimated to be 236,000 t SO 2 per year in 1988. This represents 11.7% of emissions in Southeast Asia and 0.7% of total continental Asian emissions. Emissions from vessels in transit between ports are estimated to be 226,000 t SO 2 per year, and emissions from port activities are estimated to be 10,200 t SO 2 per year. Deposition of this sulfur was calculated using the ATMOS model of atmospheric transport and deposition. Shipping emissions were found to be the dominant source of sulfur deposition in large areas of the Indian Ocean, the western Pacific Ocean, and the South China Sea. Land areas most heavily affected are those bordering the Strait of Malacca, where portions of Sumatra, peninsular Malaysia, and Singapore have contributions from shipping in excess of 10% of total sulfur deposition. Observational data in Malaysia are consistent with these findings. It is suggested that emissions from shipping may be contributing to ecological damage in areas surrounding the Strait of Malacca.

Streets, David G.; Carmichael, Gregory R.; Arndt, Richard L.

85

Detection of sulfur dioxide by cavity ring-down spectroscopy.  

PubMed

Sulfur dioxide (SO(2)) is a major air pollutant that can contribute to the production of particulate sulfate and increase the acidity in the environment. SO(2) is detected by cavity ring-down spectroscopy (CRDS) utilizing the SO(2) absorption in the 308 nm region. A ferrous sulfate scrubber and a sodium carbonate annular denuder are used to reduce background interferences and to obtain quantitative values of SO(2). The method is characterized using SO(2) standards in the laboratory and compared to a commercial pulsed fluorescence analyzer (PFA). A limit of detection of 3.5 ppb/10 s (S/N = 2) is demonstrated. Ambient measurements are attempted to demonstrate this technique. PMID:21309509

Medina, David S; Liu, Yingdi; Wang, Liming; Zhang, Jingsong

2011-03-01

86

Sorption of ozone and sulfur dioxide by petunia leaves  

SciTech Connect

Shoots of three cultivars of Petunia hybrida Vilm. of differing ozone (O/sub 3/) and sulfur dioxide (SO/sub 2/) sensitivity were exposed to O/sub 3/ and SO/sub 2/ in closed chambers for observation of pollutant absorption through the stomates and adsorption by leaf surfaces. The cultivar least sensitive to injury, Capri, absorbed the least ozone or SO/sub 2/ but adsorbed the most. The sensitive White Cascade had the opposite sorption pattern. Absorption of the individual gases was generally less from the mixture, whereas adsorption rates were similar whether the gases were supplied singly or in mixture. The existence of substantial differences in surface adsorption could introduce error in measurements of pollutant absorption by leaves.

Elkiey, T.; Ormrod, D.P.

1980-01-01

87

Band gap narrowing of titanium dioxide by sulfur doping  

NASA Astrophysics Data System (ADS)

Titanium dioxide (TiO2) doped with sulfur (S) was synthesized by oxidation annealing of titanium disulfide (TiS2). According to the x-ray diffraction patterns, TiS2 turned into anatase TiO2 when annealed at 600 degC. The residual S atoms occupied O-atom sites in TiO2 to form TiSingle_BondS bonds. The S doping caused the absorption edge of TiO2 to be shifted into the lower-energy region. Based on the theoretical analyses using ab initio band calculations, mixing of the S 3p states with the valence band was found to contribute to the band gap narrowing.

Umebayashi, T.; Yamaki, T.; Itoh, H.; Asai, K.

2002-07-01

88

Sorption and transport of sulfur dioxide in polysulfone  

SciTech Connect

The sorption and transport of sulfur dioxide (SO[sub 2]) in polymers is important in areas such as food packaging, polymer degradation, and sensors and monitoring devices. Another possible application is in pollution control for exhaust gases from power plants. Polysulfone is a polymer that is widely used for commercial gas separations with membranes. The authors have investigated the sorption and transport of SO[sub 2] in a commercially available Bisphenol A polysulfone near room temperature. The results were interpreted using the dual-mode sorption model with partial immobilization. Although similar data on other polymers have been published in the literature, they are not aware of any studies of sorption and transport of SO[sub 2] in polysulfone.

Pfromm, P.H.; Koros, W.J. (Univ. of Texas, Austin, TX (United States). Dept. of Chemical Engineering)

1993-10-25

89

Carbon fixation efficiency of plants influenced by sulfur dioxide.  

PubMed

In the land ecosystem, the forest can absorb the carbon dioxide (CO2) in the atmosphere and turn the CO2 into organic carbon to store it in the plant body. About 2×10(11) tons of CO2 changes through photosynthesis into organic matter by plant annually. In this research, ten kinds of woody plants were selected for assessing the carbon fixation ability influenced by sulfur dioxide (SO2). The tested trees were put into a fumigation chamber for 210 days in a 40-ppb SO2 environment. The results of this study showed that there was no clear symptom of tested trees under a 40-ppb SO2 environment. The tested trees could tolerate this polluted environment, but it will impact their CO2 absorption ability. The carbon fixation ability will reduce as the polluted period lengthens. The carbon fixation potential of tested trees ranged from 2.1 to 15.5 g·CO2/m2·d with an average of 7.7 g·CO2/m2·d. The changes in CO2 absorption volume for Messerschmidia argentea were more stable during the fumigation period with a variation of 102%. Among the tested trees, Diospyros morrisiana had the best carbon fixation potential of 9.19 g·CO2/m2·d and M. argentea had the least with 2.54 g·CO2/m2·d. PMID:20364315

Chung, Chung-Yi; Chung, Pei-Ling; Liao, Shao-Wei

2011-02-01

90

Real-time monitoring of sulfur dioxide using ultraviolet light-emitting diode  

NASA Astrophysics Data System (ADS)

A compact and low-cost light-emitting diode (LED) with center wavelength of 295 nm and high light density was used measure the concentration of sulfur dioxide, which has a strong structured absorption band in the ultraviolet region 300 nm. Differential optical absorption spectroscopy (DOAS) was used to determine the concentration of sulfur dioxide using reference absorption spectrum due to 1000 ppm SO2. A sensitivity of about 1.5 ppm was achieved with a gas cell in 1-s integration time, enabling real-time monitoring of sulfur dioxide.

Zhong, Weijia; Lin, Hongze; Lou, Xiutao; Yan, Chunsheng; Mei, Liang

2014-02-01

91

Novel cellulose derivative, process for preparing the same and sulfur dioxide gas permselective membrane comprising the same  

SciTech Connect

This patent relates to a novel cellulose derivative and a sulfur dioxide gas permselective membrane comprising the same, and particularly to hydrocarbylsulfinylethyl cellulose, a process for preparing the same and the sulfur dioxide gas permselective membrane comprising the same. An object of the present invention is to provide hydrocarbylsulfinylethyl cellulose which is a novel cellulose derivative and useful as a material for the sulfur dioxide gas permselective membrane and a process for preparing the same. Another object of the present invention is to supply a novel sulfur dioxide gas permselective membrane having an excellent sulfur dioxide gas permselectivity. The present invention provides hydrocarbylsulfinylethyl cellulose. The novel hydrocarbylsulfinylethyl cellulose of the present invention indicates markedly high sulfur dioxide gas permselectivity compared with the conventional cellulose derivatives, for example, cellulose acetate, ethyl cellulose, etc. Accordingly, the sulfur dioxide gas permselective membrane of the present invention can be utilized for separation, purification of sulfur dioxide gas from a gas mixture such as air or for concentration of sulfur dioxide gas in a gas mixture, and is highly practical in industrial use. More specifically, the sulfur dioxide gas permselective membrane is useful for, for example, removal of harmful sulfur dioxide gas from discharged gases from the viewpoint of environmental protection and purification of starting gases for synthesis, etc. from the viewpoint of industrial production. Further, the hydrocarbylsulfinylethyl cellulose of the present invention is useful for a thickening agent, binder, protective colloidal agent, etc.

Imai, K.; Shiomi, T.; Tezuka, Y.

1987-09-15

92

Electrochemical oxidation of wine polyphenols in the presence of sulfur dioxide.  

PubMed

Electrochemical oxidation of three representative wine polyphenols (catechin, caffeic acid, and quercetin) in the presence of sulfur dioxide in a model wine solution (pH = 3.3) was investigated. The oxidation was undertaken using chronoamperometry at a rotating glassy carbon rod electrode, and the reaction products were characterized by HPLC-MS. The mechanism of electrochemical oxidation of polyphenols in the presence of sulfur dioxide was proposed to be an ECEC mechanism. The polyphenols first underwent a one-electron oxidation to a semiquinone radical, which can be reduced back to the original polyphenol by sulfur dioxide, or further oxidized to the quinone form. In the cases of caffeic acid and catechin, the quinone combined with sulfur dioxide and produced new derivatives. The quercetin quinone underwent further chemical transformations, producing several new compounds. The proposed mechanisms were confirmed by digital simulation of cyclic voltammograms. PMID:23692398

Makhotkina, Olga; Kilmartin, Paul A

2013-06-12

93

GROUND-BASED SULFUR DIOXIDE MEASUREMENTS WITHIN A COPPER SMELTER PLUME - ANACONDA, MONTANA  

EPA Science Inventory

The Monitoring Operations Division (MOD) of the Environmental Monitoring and Support Laboratory - Las Vegas developed a mobile sulfur dioxide (SO2) instrument package for use in the remote, rugged terrain surrounding The Anaconda Company's copper smelter at Anaconda, Montana. The...

94

Control of Sulfur Dioxide Emissions from Copper Smelters: Volume II. Hydrogen Sulfide Production from Copper Concentrates.  

National Technical Information Service (NTIS)

A laboratory investigation has been made of a modified copper smelting process which provides a solution to the sulfur dioxide air pollution problem. Preliminary economic evaluation of the process appears favorable with good prospects for further improvem...

C. A. Rohrmann H. T. Fullam

1974-01-01

95

Modification of the Sulfur Dioxide-Iodine Thermochemical Hydrogen Cycle with Lanthanum Sulfites and Sulfates.  

National Technical Information Service (NTIS)

Variable composition, insoluble dilanthanum oxide-sulfite-sulfate-hydrates were prepared by reaction of lanthanum dioxymonosulfate with aqueous sulfur dioxide. These compositions reacted with iodine to yield sulfate in the solid phase, and hydrogen iodide...

E. I. Onstott M. G. Bowman M. F. Michnovicz C. M. Hollabaugh

1984-01-01

96

Reactions for Improving Efficiencies in Thermochemical Cycles Related to the Sulfur Dioxide-Iodine Process.  

National Technical Information Service (NTIS)

A modification of the sulfur dioxide-iodine cycle which uses magnesium oxide, magnesium sulfite and magnesium iodide is examined with particular emphasis on decreasing the amount of water employed and thereby increasing the efficiency. The key reaction is...

C. F. V. Mason M. G. Bowman

1982-01-01

97

Sulfur dioxide emissions from primary copper smelters in the western US  

SciTech Connect

The body of information presented is directed to environmental scientists and policy makers without chemical or metallurgical engineering backgrounds. This paper addresses the problems of reducing sulfur dioxide emissions from primary copper smelters in the western United States and projects the future impact of emissions within a framework of legal, technological, and economic considerations. Methodology used to calculate historical sulfur dioxide emissions is described. Sulfur dioxide emission regulations are outlined as they apply to primary copper smelters. A discussion of available sulfur dioxide control technology and copper smelting processes summarizes the technological and economic problems of reducing copper smelter emissions. Based upon these technological and economic considerations, projections of smelter emissions indicate that compliance with existing legislative requirements will be achieved by 1990. Three smelters are projected to close by 1985.

Mangeng, C.A.; Mead, R.W.

1980-01-01

98

Sulfur Dioxide emission from Mt Pinatubo Eruption June 1991 with dates  

NSDL National Science Digital Library

This animation shows sulfur dioxide in the stratosphere during the Mt. Pinatubo Eruption and for a few weeks after the eruption. Stratospheric SO2 dissipates rather quickly compared to volcanic ash and stratoshperic H2SO4.

Perkins, Lori; Mcpeters, Richard; Herman, Jay

2001-06-12

99

77 FR 46295 - Extension of Deadline for Promulgating Designations for the 2010 Primary Sulfur Dioxide National...  

Federal Register 2010, 2011, 2012, 2013

...initial area designations for the primary sulfur dioxide (SO 2 ) national ambient...to these commenters, we explained our modified expectations at that time for issuing...tribal agencies that described the EPA's modified expectations regarding some SO 2...

2012-08-03

100

75 FR 81471 - Approval and Promulgation of Air Quality Implementation Plans; Minnesota; Sulfur Dioxide SIP...  

Federal Register 2010, 2011, 2012, 2013

...Minnesota; Sulfur Dioxide SIP Revision for Marathon Petroleum St. Paul Park AGENCY: Environmental...State Implementation Plan revision for Marathon Petroleum in St. Paul Park. This submittal...Implementation Plan (SIP) revision request for Marathon Petroleum Co, LLC, (Marathon)...

2010-12-28

101

Gaseous sulfuric acid and sulfur dioxide measurements in the Arctic troposphere and lower stratosphere - Implications for hydroxyl radical abundances  

Microsoft Academic Search

Measurements of gaseous sulfuric acid and sulfur dioxide were made in the winter Arctic troposphere and lower stratosphere using aircraft-borne mass spectrometers. The measurements, covering altitudes between 3.5 and 11.4 km, took place on 14 and 18 February, 1987 in northern Scandinavia. The abundance of H2SO4 was around 0.01 to 0.06 pptv (parts per trillion by volume), and the measured

O. Moehler; F. Arnold

1992-01-01

102

Absorption of sulfur dioxide into aqueous sodium hydroxide and sodium sulfite solutions  

Microsoft Academic Search

The rates of absorption of pure sulfur dioxide into aqueous sodium bisulfite, sodium hydroxide, and sodium sulfite solutions with and without a surface active agent were measured at 25°C using a liquid jet column. For the sulfur dioxide-sodium hydroxide system, the rate of absorption into the solution without surface active agent was higher than that into the solution with surface

Haruo Hikita; Satoru Asai; Tadashi Tsuji

1977-01-01

103

Ambient air concentration of sulfur dioxide affects flight activity in bees  

SciTech Connect

Three long-term (16 to 29 days) low-level (0.14 to 0.28 ppM) sulfur dioxide fumigations showed that exposure tothis gas has deleterious effects on male sweat bees (Lasioglossum zephrum). Although effects on mortality were equivocal, flight activity was definitely reduced. Because flight is necessary for successful mating behavior, the results suggest that sulfur dioxide air pollution could adversely affect this and doubtless other terrestrial insects.

Ginevan, M.E.; Lane, D.D.; Greenberg, L.

1980-10-01

104

Effect of mixing conditions on irritant potency of zinc oxide and sulfur dioxide. [Guinea pigs  

Microsoft Academic Search

Measurement of mechanics of respiration in guinea pigs was used to assess the irritant potency of zinc oxide and sulfur dioxide mixed under different conditions of temperature and humidity. Concentrations were 1-2 mg\\/m³ zinc oxide and 1 ppm sulfur dioxide. Dry conditions of mixing (Chamber RH 30%) either at 24°C in the exposure chamber or at 480°C in a dry

M. O. Amdur; J. F. McCarthy; M. W. Gill

1983-01-01

105

Effect of Mixing Conditions on Irritant Potency of Zinc Oxide and Sulfur Dioxide  

Microsoft Academic Search

Measurement of mechanics of respiration in guinea pigs was used to assess the irritant potency of zinc oxide and sulfur dioxide mixed under different conditions of temperature and humidity. Concentrations were 1-2?mg\\/m zinc oxide and 1?ppm sulfur dioxide. Dry conditions of mixing (Chamber RH 30%) either at 24°C in the exposure chamber or at 480°C in a dry furnace gave

MARY O. AMDUR; JOHN F. McCARTHY; MICHAEL W. GILL

1983-01-01

106

The Survival of Airborne Serratia marcescens in Urban Concentrations of Sulfur Dioxide  

Microsoft Academic Search

Aerosols of Serratia marcescens ATCC 274 were suspended in a 709L rotating drum at 20 ± 1 °C and high to mid-range relative humidities. At specified times after bacterial aerosolization, sulfur dioxide was added to concentrations of 2.5, or 5 mg\\/m. Viable cell decay rate constants, in control aerosols without added sulfur dioxide, increased rapidly from near 100% to 60%

Bruce Lighthart; Victor E. Hiatt; August T. Rossano Jr

1971-01-01

107

Adsorption of sulfur dioxide from coal combustion gases on natural zeolite  

SciTech Connect

In this study, better efficiency of SO{sub 2} removal in flue gas from lignite coal combustion by adding of NZ in the gas phase was achieved. Natural zeolite was exposed to flue gas containing sulfur dioxide at varying conditions of relative humidity and temperature. It was found that the amount of sulfate on the zeolite increased with increasing relative humidity and temperature. The percents of adsorbed sulfur dioxide were 86, 74, 56, and 35, while the values of relative humidity (RH) were 75, 60, 45, and 30% for 40 minutes, respectively. The percents of adsorbed sulfur dioxide sharply increased within the first 40 min for the values of RH were 75 and 60, and after 40 min, slightly increased, then reached a plateau. In general, as increasing the RH increased the amount of sulfur dioxide adsorbed by natural zeolite. The amounts of adsorbed sulfur dioxide increased with exposure time. It increased and reached 30.2 mg/g for 40 min. After 40 min, it slightly increased and then reached a plateau. The NZ adsorbs 35.1 mg SO{sub 2} per gram adsorbent with 75% RH at 298 K from a simulated coal combustion flue gas. The amounts of adsorbed sulfur dioxide increased with increasing temperature. The NZ adsorbs 71.5 mg SO{sub 2} per gram adsorbent with 75% RH for 100 min exposure time from the flue gas mixture.

Demirbas, A. [Selcuk University, Konya (Turkey). Dept. for Chemical Engineering

2006-10-15

108

Sulfur dioxide-induced chronic bronchitis in beagle dogs  

SciTech Connect

This study was done to produce a model of chronic bronchitis. Twelve beagle dogs were exposed to 500 ppm sulfur dioxide (SO/sub 2/) for 2 h/d, 5d/wk for 21 wk and 4 dogs were sham-exposed to filtered ambient air for the same period. Exposure effects were evaluated by periodically examining the dogs using chest radiographs, pulmonary function, tracheal mucous clearance, and the cellular and soluble components of bronchopulmonary lavage fluids. Dogs were serially sacrificed after 13 and 21 wk of exposure and after 6 and 14 wk of recovery. Clinical signs produced in the SO/sub 2/-exposed dogs included mucoid nasal discharge, productive cough, moist rales on auscultation, tonsilitis, and conjunctivitis. Chest radiographs revealed mild peribronchiolar thickening. Histopathology, tracheal mucous clearance measurements, and lavage cytology were consistent with a diagnosis of chronic bronchitis. It is concluded that repeated exposure to 500 ppm SO/sub 2/ for 21 wk produced chronic bronchitis in the beagle dog. Complete recovery occurred within 5 wk following cessation of SO/sub 2/ exposure. 43 references, 2 figures, 2 tables.

Greene, S.A.; Wolff, R.K.; Hahn, F.F.; Henderson, R.F.; Mauderly, J.L.; Lundgren, D.L.

1984-01-01

109

DNA damage in mice treated with sulfur dioxide by inhalation.  

PubMed

Sulfur dioxide (SO2) is a ubiquitous air pollutant produced by the burning of fossil fuels. In this study, single-cell gel electrophoresis (the Comet assay) was used to evaluate the DNA damage produced by inhalation exposure of mice to SO2. Male and female mice were housed in exposure chambers and treated with 14.00 +/- 1.25, 28.00 +/- 1.98, 56.00 +/- 3.11, and 112.00 +/- 3.69 mg/m3 SO2 for 6 hr/day for 7 days, while control groups were exposed to filtered air. Comet assays were performed on blood lymphocytes and cells from the brain, lung, liver, spleen, kidney, intestine, and testicles of the animals. SO2 caused significant, dose-dependent increases in DNA damage, as measured by Olive tail moment, in all the cell types analyzed from both sexes of mice. The results indicate that inhalation exposure to SO2 damages the DNA of multiple organs in addition to the lung, and suggests that this damage could result in mutation, cancer, and other diseases related to DNA damage. Further work will be required to understand the ultimate toxicological significance of this damage. These data also suggest that detecting DNA damage in blood lymphocytes, using the Comet assay, may serve as a useful tool for evaluating the impact of pulmonary SO2 exposure in human biomonitoring studies. PMID:15898097

Meng, Ziqiang; Qin, Guohua; Zhang, Bo

2005-10-01

110

Particulate and sulfur dioxide concentration measurements in Patras, Greece.  

PubMed

The purpose of this study was to obtain a better assessment of the Patras, Greece, air quality, in terms of the primary pollutants total suspended particulates (TSPs) and sulfur dioxide (SO2), because limited and short-duration measurements have been conducted in the past. Installation and operation of a mobile air monitoring station at two different locations in the Patras downtown area and one location in the outskirts of the city was undertaken and covered the periods July 1, 1994-January 30, 1995; March 18-August 23, 1995; and April 19-July 27, 1996, respectively. For both pollutants measured at each location, the monthly average concentrations and typical weekly variation of daily averages, as well as the diurnal variations and frequency concentration distributions in each month of the monitoring periods, were calculated and are presented in bar diagrams. The annual and winter period medians and the annual 98th percentile were also calculated and are compared with the limit and guide values provided by the European Economic Community Council Directive 80/779/EEC. In addition, comparison of SO2 values is made with the limit values adopted by the more recent Directive 1999/30/EC. It was found that the TSP and SO2 levels at all locations were very low and were lower than the levels found in Thessaloniki and Athens, Greece. An attempt to explain what had been measured is also undertaken. The data presented are considered essential for future reference and comparison purposes. PMID:12943315

Yannopoulos, Panayotis C; Skokaki, Georgia N

2003-08-01

111

Process for removing sulfur dioxide from flue gases  

SciTech Connect

This patent describes an improvement in a dry process for the removal of sulfur dioxide from flue gases by the addition thereto of hydrated lime containing sugar in a coal combustion unit, wherein the flue gases result from the combustion of a coal in a combustion chamber, and the flue gases are treated in an electrostatic precipitator prior to discharge to the atmosphere the improvement comprising: passing the flue gases, after the addition of the hydrated lime is of fine particles of a specific surface of 7 to 25 square meters per gram, through a conduit towards the electrostatic precipitator; and adding an aqueous media to the flue gases in the conduit in an amount to increase the water content of the flue gases and cool the same by evaporative cooling to a temperature no lower than 20{sup 0}F. about the dew point of the gas, so as to avoid forming water droplets in the gas, so as to prevent condensation of water therefrom.

Robinson, M.W. Jr.

1989-08-29

112

Pulmonary effects of sulfur dioxide and respirable carbon aerosol  

SciTech Connect

Four-hour individual and combined exposures to 1.0 ppm sulfur dioxide (SO/sub 2/) and 0.5 mg/m/sup 3/ (1.5 ..mu..m mass median diameter) activated carbon aerosol (ACA) were studied in 20 healthy nonsmoking subjects to determine if activated carbon as a carrier aerosol can augment the pulmonary response to SO/sub 2/. Fifteen-minute exercise stints (V/sub E/ = 35 liters/min) were performed at commencement and completion of each 4-hr period. Significant increases in nose or throat irritation occurred with the SO/sub 2/ and SO/sub 2/ + ACA exposures and in eye irritation with the SO/sub 2/ + ACA exposure. Small, statistically significant decrements in spirometric function were observed following the first exercise (t = 17 min) for both the SO/sub 2/ and SO/sub 2/ plus ACA exposures: no significant changes were associated with the ACA exposure. Comparing function changes between the SO/sub 2/ and the SO/sub 2/ + ACA exposures demonstrated no statistically significant differences, thus a lack of SO/sub 2/ response enhancement by the carbon aerosol. The determination that the activated carbon sorbed only 1% of the SO/sub 2/ challenge concentration could explain the observed lack of SO/sub 2/ response enhancement.

Kulle, T.J.; Sauder, L.R.; Hebel, J.R.; Miller, W.R.; Green, D.J.; Shanty, F.

1986-10-01

113

40 CFR Appendix A-1 to Part 50 - Reference Measurement Principle and Calibration Procedure for the Measurement of Sulfur Dioxide...  

Code of Federal Regulations, 2013 CFR

...standards for sulfur oxides (sulfur dioxide) as specified...and possibly other compounds, in the air sample to...interferences from these compounds, which may be present...interferences. These gases can be removed by using...known concentrations of sulfur dioxide are...

2013-07-01

114

Sulfur dioxide emissions from primary copper smelters in the western US  

Microsoft Academic Search

The body of information presented is directed to environmental scientists and policy makers without chemical or metallurgical engineering backgrounds. This paper addresses the problems of reducing sulfur dioxide emissions from primary copper smelters in the western United States and projects the future impact of emissions within a framework of legal, technological, and economic considerations. Methodology used to calculate historical sulfur

C. A. Mangeng; R. W. Mead

1980-01-01

115

Market Efficiency and U.S. Market for Sulfur Dioxide Allowances. Working Paper 2014-01.  

National Technical Information Service (NTIS)

Focusing on the U.S. sulfur dioxide (SO2) allowance market from its inception (in 1994) to 2009, we model allowance prices to determine the influence of market fundamentals such as prices of high- and low-sulfur coalon allowance price level and volatility...

A. Stocking C. Hitaj

2014-01-01

116

Simultaneous sulfur dioxide and nitrogen dioxide removal by calcium hydroxide and calcium silicate solids.  

PubMed

At conditions typical of a bag filter exposed to a coal-fired flue gas that has been adiabatically cooled with water, calcium hydroxide and calcium silicate solids were exposed to a dilute, humidified gas stream of nitrogen dioxide (NO2) and sulfur dioxide (SO2) in a packed-bed reactor. A prior study found that NO2 reacted readily with surface water of alkaline and non-alkaline solids to produce nitrate, nitrite, and nitric oxide (NO). With SO2 present in the gas stream, NO2 also reacted with S(IV), a product of SO2 removal, on the exterior of an alkaline solid. The oxidation of S(IV) to S(VI) by oxygen reduced the availability of S(IV) and lowered removal of NO2. Subsequent acidification of the sorbent by the removal of NO2 and SO2 facilitated the production of NO. However, the conversion of nitrous acid to sulfur-nitrogen compounds reduced NO production and enhanced SO2 removal. A reactor model based on empirical and semi-empirical rate expressions predicted rates of SO2 removal, NO2 removal, and NO production by calcium silicate solids. Rate expressions from the reactor model were inserted into a second program, which predicted the removal of SO2 and NOx by a continuous process, such as the collection of alkaline solids in a baghouse. The continuous process model, depending upon inlet conditions, predicted 30-40% removal for NOx and 50-90% removal for SO2. These results are relevant to dry scrubbing technology for combined SO2 and NOx removal that first oxidizes NO to NO2 by the addition of methanol into the flue duct. PMID:9775761

Nelli, C H; Rochelle, G T

1998-09-01

117

Distribution of Hydrogen Peroxide, Carbon Dioxide, and Sulfuric Acid in Europa's Icy Crust  

NASA Technical Reports Server (NTRS)

Galileo's Near Infrared Mapping Spectrometer (NIMS) detected hydrogen peroxide, carbon dioxide and a hydrated material on Europa's surface, the latter interpreted as hydrated sulfuric acid (H2SO4*nH2O) or hydrated salts. Related compounds are molecular oxygen, sulfur dioxide, and two chromophores, one that is dark in the ultraviolet(UV) and concentrated on the trailing side, the other brighter in the UV and preferentially distributed in the leading hemisphere. The UV-dark material has been suggested to be sulfur.

Carlson, R. W.

2004-01-01

118

40 CFR 60.642 - Standards for sulfur dioxide.  

Code of Federal Regulations, 2010 CFR

...Performance for Onshore Natural Gas Processing: Sec. 60.642...the sulfur content of the acid gas (Y) of the affected facility...the sulfur content of the acid gas (Y) of the affected facility. [[Page 650

2009-07-01

119

Seasonal trends of atmospheric nitrogen dioxide and sulfur dioxide over North Santa Clara, Cuba.  

PubMed

Atmospheric nitrogen dioxide (NO2) and sulfur dioxide (SO2) levels were monitored simultaneously by means of Radiello passive samplers at six sites of Santa Clara city, Cuba, in the cold and the warm seasons in 2010. The dissolved ionic forms of NO2 and SO2 as nitrate and sulfite plus sulfate, respectively, were determined by means of ion chromatography. Analysis of NO2 as nitrite was also performed by UV-Vis spectrophotometry. For NO2, significant t tests show good agreement between the results of IC and UV-Vis methods. The NO2 and SO2 concentrations peaked in the cold season, while their minimum levels were experienced in the warm season. The pollutant levels do not exceed the maximum allowable limit of the Cuban Standard 39:1999, i.e., 40 ?g/m(3) and 50 ?g/m(3) for NO2 and SO2, respectively. The lowest pollutant concentrations obtained in the warm season can be attributed to an increase in their removal via precipitation (scavenging) while to the decreased traffic density and industrial emission during the summer holidays (e.g., July and August). PMID:23208757

Alejo, Daniellys; Morales, Mayra C; de la Torre, Jorge B; Grau, Ricardo; Bencs, László; Van Grieken, René; Van Espen, Piet; Sosa, Dismey; Nuñez, Vladimir

2013-07-01

120

Atmospheric measurements of carbonyl sulfide, dimethyl sulfide, and carbon disulfide using the electron capture sulfur detector  

NASA Technical Reports Server (NTRS)

Measurements of atmospheric dimethyl sulfide (DMS), carbonyl sulfide (COS), and carbon disulfide (CS2) were conducted over the Atlantic Ocean on board the NASA Electra aircraft during the Chemical Instrumentation Test and Evaluation (CITE 3) project using the electron capture sulfur detector (ECD-S). The system employed cryogenic preconcentration of air samples, gas chromatographic separation, catalytic fluorination, and electron capture detection. Samples collected for DMS analysis were scrubbed of oxidants with NaOH impregnated glass fiber filters to preconcentration. The detection limits (DL) of the system for COS, DMS, and CS2 were 5, 5, and 2 ppt, respectively. COS concentrations ranged from 404 to 603 ppt with a mean of 489 ppt for measurements over the North Atlantic Ocean (31 deg N to 41 deg N), and from 395 to 437 ppt with a mean of 419 ppt for measurements over the Tropical Atlantic Ocean (11 deg S to 2 deg N). DMS concentrations in the lower marine boundary layer, below 600-m altitude, ranged from below DL to 150 ppt from flights over the North Atlantic, and from 9 to 104 ppt over the Tropical Atlantic. CS2 concentrations ranged from below DL to 29 ppt over the North Atlantic. Almost all CS2 measurements over the Tropical Atlantic were below DL.

Johnson, James E.; Bates, Timothy S.

1993-01-01

121

Atmospheric measurements of carbonyl sulfide, dimethyl sulfide, and carbon disulfide using the electron capture sulfur detector  

SciTech Connect

Measurements of atmospheric dimethyl sulfide (DMS), carbonyl sulfide (COS), and carbon disulfide (CS2) were conducted over the Atlantic Ocean on board the NASA Electra aircraft during the Chemical Instrumentation Test and Evaluation (CITE 3) project using the electron capture sulfur detector (ECD-S). The system employed cryogenic preconcentration of air samples, gas chromatographic separation, catalytic fluorination, and electron capture detection. Samples collected for DMS analysis were scrubbed of oxidants with NaOH impregnated glass fiber filters to preconcentration. The detection limits (DL) of the system for COS, DMS, and CS2 were 5, 5, and 2 ppt, respectively. COS concentrations ranged from 404 to 603 ppt with a mean of 489 ppt for measurements over the North Atlantic Ocean (31 deg N to 41 deg N), and from 395 to 437 ppt with a mean of 419 ppt for measurements over the Tropical Atlantic Ocean (11 deg S to 2 deg N). DMS concentrations in the lower marine boundary layer, below 600-m altitude, ranged from below DL to 150 ppt from flights over the North Atlantic, and from 9 to 104 ppt over the Tropical Atlantic. CS2 concentrations ranged from below DL to 29 ppt over the North Atlantic. Almost all CS2 measurements over the Tropical Atlantic were below DL.

Johnson, J.E.; Bates, T.S. [NOAA, Seattle, WA (United States)

1993-12-01

122

Application of synthetic molecular sieve zeolites and silica gel towards the separation of sulfur dioxide from combustion gases  

Microsoft Academic Search

Sulfur dioxide loadings were greatest for the type 13X molecular sieve followed by AW500 molecular sieve. The effect of gas throughput was minimal which suggests that mass transfer was adsorbent side controlling. As gas temperature increased, sulfur dioxide adsorption decreased linearly for 100 percent sulfur dioxide concentration and non-linearly for low concentrations (0.003 percent). The effect of water vapor on

1979-01-01

123

Solubility of hydrogen sulfide, sulfur dioxide, carbon dioxide, propane, and n-butane in poly(glycol ethers)  

Microsoft Academic Search

Data on the solubility of acid and hydrocarbon gases for poly(glycol ethers) are necessary for the development of the University of California, Berkeley, Sulfur Removal Process. An automated gas solubility measurement system was used to collect data on the solubility of hydrogen sulfide, carbon dioxide, propane, and n-butane in a variety of these solvents. The partial pressure of solute gas

Steven F. Sciamanna; Scott Lynn

1988-01-01

124

SYNTHESIS OF SULFUR-BASED WATER TREATMENT AGENT FROM SULFUR DIOXIDE WASTE STREAMS  

SciTech Connect

Absorption of sulfur dioxide from a simulated flue gas was investigated for the production of polymeric ferric sulfate (PFS), a highly effective coagulant useful in treatment of drinking water and wastewater. The reaction for PFS synthesis took place near atmospheric pressure and at temperatures of 30-80 C. SO{sub 2} removal efficiencies greater than 90% were achieved, with ferrous iron concentrations in the product less than 0.1%. A factorial analysis of the effect of temperature, oxidant dosage, SO{sub 2} concentration, and gas flow rate on SO{sub 2} removal efficiency was carried out, and statistical analyses are conducted. The solid PFS was also characterized with different methods. Characterization results have shown that PFS possesses both crystalline and non-crystalline structure. The kinetics of reactions among FeSO{sub 4} {center_dot} 7H{sub 2}O, NaHSO{sub 3} and NaClO{sub 3} was investigated. The PFS product was used in pilot-scale tests at a municipal water treatment facility and gave good results in removal of turbidity and superior results in removal of disinfection byproduct precursors (TOC, DOC, UV-254) when compared with equal doses of ferric chloride.

Robert C. Brown; Maohong Fan; Adrienne Cooper

2002-10-01

125

Statistical summary and trend evaluation of air quality data for Cleveland, Ohio in 1967 to 1971: Total suspended particulate, nitrogen dioxide, and sulfur dioxide  

NASA Technical Reports Server (NTRS)

Air quality data for Cleveland, Ohio, for the period of 1967 to 1971 were collated and subjected to statistical analysis. The total suspended particulate component is lognormally distributed; while sulfur dioxide and nitrogen dioxide are reasonably approximated by lognormal distributions. Only sulfur dioxide, in some residential neighborhoods, meets Ohio air quality standards. Air quality has definitely improved in the industrial valley, while in the rest of the city, only sulfur dioxide has shown consistent improvement. A pollution index is introduced which displays directly the degree to which the environmental air conforms to mandated standards.

Neustadter, H. E.; Sidik, S. M.; Burr, J. C., Jr.

1972-01-01

126

Optical sensor for sulfur dioxide determination in wines.  

PubMed

A method for the determination of free and total sulfur dioxide in wines, based on the use of an optical sensor that employs a dichlorobis(diphenylphosphino)methane dipalladium I complex [Pd(2)(dppm)(2)Cl(2)] immobilized in a PVC membrane plasticized with o-nitrophenyloctylether (o-NPOE) is described. A sensing membrane [4.2% Pd(2)(dppm)(2)Cl(2), 20.8% PVC, and 75% o-NPOE] was adapted to the tip of a bifurcated optical fiber bundle to perform reflectance measurements at 550 nm. The detection system consisted of two cells (40 mL), which hold the sample solution (plus reagents) and the optical sensor, respectively. For the determination of free SO(2), a wine sample was mixed with H(2)SO(4) solution in the sample cell, into which N(2) was bubbled, providing mixing of the solutions and conducting the SO(2) formed toward the detection cell. For determination of total SO(2), a KOH solution was mixed with the wine in the sample cell. Afterward, an H(2)SO(4) solution was added to the cell, and then N(2) was bubbled to conclude the measurement. Linear responses up to 50 and 150 mg L(-1) were obtained for free and total SO(2), with detection limits of 0.37 and 0.70 mg L(-1), respectively. The repeatability of the method was evaluated by carrying out 10 measurements using a single wine sample, providing relative standard deviation values of 2.2 and 2.5% for free and total SO(2), respectively. The sensing membrane prepared from 10 muL of the cocktail solution lasted for 80 measurements, whereas those prepared from 200 muL can be used for 250 measurements. The method was applied to free and total SO(2) determination in wines, and the results did not show significant difference from those obtained with the Ripper reference method at a confidence level of 95%. PMID:17090109

Silva, Karime R B; Raimundo, Ivo M; Gimenez, Iara F; Alves, Oswaldo L

2006-11-15

127

P135Sulfur dioxide derivative prevents isoproterenol induced electrophysiological alterations.  

PubMed

Excitation-contraction coupling in cardiac muscle of hypertrophic cardiomyopathy (HCM) remains poorly understood, despite the fact that the genetic alterations are well defined. In this sense, many intracellular signaling molecules and pathways has been tested. Among these, the most interesting ones are carbon monoxide (CO), nitrogen monoxide (NO) and hydrogen sulfide (H2S) referred to as the gasotransmitters. These molecules have been identified primarly as contaminants of the environment. In addition to these substances, sulfur dioxide (SO2) is the one that still investigated in the same way. Recent studies regarding the heart muscle beside other organs, SO2 is endogenously produced and possible intercellular signaling molecule. However, the influence on heart's electrical and mechanical functions is unknown. This study was designed to uncover the potential role of SO2 in rat model of HCM generated by excessive ?-adrenergic stimulation was used. Single cells have been obtained by enzymatically from hearts of wistar rats given ?-adrenergic agonist isoproterenol (25 mg per kg body weight per day) subcutaneously to generate HCM and/or SO2 donor sodium metabisulfite (85 mg per kg body weight per day) for 7 days (i.p). It has been found that SO2 had no effect on isoproterenol induced hypertrophy via examining heart weight/tibia length ratio. It is observed that lengthening at repolarization phase of action potential in the animal model and SO2 application reversed this process. Moreover, isoproterenol treatment reduced L-type Ca2+ current, it was returned to control levels by application of SO2. Experimental HCM model leads to adverse changes in mechanical parameters, even though SO2 causes improvement in the electrophysiological parameters. Also shortening in the resting sarcomere length along with decreasing contraction amplitude in isoproterenol and SO2 applied animals would interpret diastolic dysfunction due to increased Ca2+ sensitivity. Also isoproterenol induced cardiac damage were not caused by oxidation since no difference observed on protein oxidation and lipid peroxidation measurements. However, it is determined that SO2 application alone does increase protein carbonyl values. In this context, while SO2 molecule creates oxidative stress in physiological condition, different effects on the organism can be revealed depending on the physiological conditions. Consequently, the data have implied that SO2 molecule has possible effect on cardiovascular system pathology and on electrophysiology of heart. In order to fully understand of this effect, detailed studies are required. PMID:25020555

Yaras, N; Ozdemir, S; Dalaman, U; Ozdogan, H

2014-07-15

128

40 CFR 60.163 - Standard for sulfur dioxide.  

Code of Federal Regulations, 2013 CFR

... Standards of Performance for Primary Copper Smelters § 60.163 Standard for sulfur...from any roaster, smelting furnace, or copper converter any gases which contain sulfur...the total smelter charge at the primary copper smelter contains a high level of...

2013-07-01

129

Testing of an improved lithium-sulfur dioxide battery for aircrew life support equipment  

NASA Astrophysics Data System (ADS)

This report presents the results of in-house testing of lithium-sulfur dioxide cells. The report includes performance testing of an engineering prototype design of lithium-sulfur dioxide cells and the performance characterization, storage evaluations and abuse test behavior of the pilot production cell design. Several design modifications occurred during the development of this lithium-sulfur dioxide cell technology which significantly changed their performance. Testing of the pilot production cells included: (1) Performance evaluations at rates of 50MA, 100MA, 200MA, and 400 MA at temperatures from -65 F to +140 F; (2) Room temperature discharge tests at high rates of current; (3) Capacity retention capability as a function of storage time at temperatures of 32 F, 70 F and 160 F; (4) Evaluation of intermittent storage capability at 205 F; and (5) Abuse testing. Abuse testing included short circuit, nail penetration, and forced overdischarge conditions.

Cloyd, J. S.

1982-05-01

130

Modelling and Remote Sensing of Ash and Sulfur Dioxide from the 2008 Kasatochi Volcano Eruption  

NASA Astrophysics Data System (ADS)

We simulated the formation, evolution and transport of volcanic ash and sulfur dioxide (SO2) from the 2008 eruption of Kasatochi volcano using the Weather Research Forecasting (WRF) with inline Chemistry (WRF-Chem). The volcano is located at the western Aleutian arc, and the ash and SO2 plume dispersed well over the North American continent. Using the Regional Acid Deposition Model, version 2 (RADM2) within WRF-Chem, we describe the conversion of sulfur dioxide to sulfate aerosols. WRF-Chem was further set up to use the GOCART aerosol module for predicting the fate of the sulfate aerosol downwind from the volcano. We validated model output with temporal and spatial comparisons to data available from various satellite borne sensors, including OMI, AIRS and MODIS. Temporal and special agreement between WRF and sensor data is discussed and the feasibility of using WRF-Chem as a tool for volcanic sulfur dioxide and ash prediction is assessed.

Egan, S.; Stuefer, M.

2013-12-01

131

Sulfur dioxide emissions in China and sulfur trends in East Asia since 2000  

NASA Astrophysics Data System (ADS)

With the rapid development of the economy, the sulfur dioxide (SO2) emission from China since 2000 is of increasing concern. In this study, we estimate the annual SO2 emission in China after 2000 using a technology-based methodology specifically for China. From 2000 to 2006, total SO2 emission in China increased by 53%, from 21.7 Tg to 33.2 Tg, at an annual growth rate of 7.3%. Emissions from power plants are the main sources of SO2 in China and they increased from 10.6 Tg to 18.6 Tg in the same period. Geographically, emission from north China increased by 85%, whereas that from the south increased by only 28%. The emission growth rate slowed around 2005, and emissions began to decrease after 2006 mainly due to the wide application of Flue-Gas Desulfurization (FGD) devices in power plants in response to a new policy of China's government. This paper shows that the trend of estimated SO2 emission in China is consistent with the trends of SO2 concentration and acid rain pH and frequency in China, as well as with the increasing trends of background SO2 and sulfate concentration in East Asia. A longitudinal gradient in the percentage change of urban SO2 concentration in Japan is found during 2000-2007, indicating that the decrease of urban SO2 is lower in areas close to the Asian continent. This implies that the transport of increasing SO2 from the Asian continent partially counteracts the local reduction of SO2 emission downwind. The Aerosol Optical Depth (AOD) products of Moderate Resolution Imaging Spectroradiometer (MODIS) are found to be highly correlated with the Surface Solar Radiation (SSR) measurements in East Asia. Using MODIS AOD data as a surrogate of SSR, we found that China and East Asia excluding Japan underwent a continuous dimming after 2000, which is in line with the dramatic increase in SO2 emission in East Asia. The trends of AOD from both satellite retrievals and model over East Asia are also consistent with the trend of SO2 emission in China, especially during the second half of the year, when sulfur contributes the largest fraction of AOD. The arrested growth in SO2 emissions since 2006 is also reflected in the decreasing trends of SO2 and SO42- concentrations, acid rain pH values and frequencies, and AOD over East Asia.

Lu, Z.; Streets, D. G.; Zhang, Q.; Wang, S.; Carmichael, G. R.; Cheng, Y. F.; Wei, C.; Chin, M.; Diehl, T.; Tan, Q.

2010-04-01

132

Sulfur dioxide emissions in China and sulfur trends in East Asia since 2000  

NASA Astrophysics Data System (ADS)

With the rapid development of the economy, the sulfur dioxide (SO2) emission from China since 2000 is of increasing concern. In this study, we estimate the annual SO2 emission in China after 2000 using a technology-based methodology specifically for China. From 2000 to 2006, total SO2 emission in China increased by 53%, from 21.7 Tg to 33.2 Tg, at an annual growth rate of 7.3%. Emissions from power plants are the main sources of SO2 in China and they increased from 10.6 Tg to 18.6 Tg in the same period. Geographically, emission from north China increased by 85%, whereas that from the south increased by only 28%. The emission growth rate slowed around 2005, and emissions began to decrease after 2006 mainly due to the wide application of flue-gas desulfurization (FGD) devices in power plants in response to a new policy of China's government. This paper shows that the trend of estimated SO2 emission in China is consistent with the trends of SO2 concentration and acid rain pH and frequency in China, as well as with the increasing trends of background SO2 and sulfate concentration in East Asia. A longitudinal gradient in the percentage change of urban SO2 concentration in Japan is found during 2000-2007, indicating that the decrease of urban SO2 is lower in areas close to the Asian continent. This implies that the transport of increasing SO2 from the Asian continent partially counteracts the local reduction of SO2 emission downwind. The aerosol optical depth (AOD) products of Moderate Resolution Imaging Spectroradiometer (MODIS) are found to be highly correlated with the surface solar radiation (SSR) measurements in East Asia. Using MODIS AOD data as a surrogate of SSR, we found that China and East Asia excluding Japan underwent a continuous dimming after 2000, which is in line with the dramatic increase in SO2 emission in East Asia. The trends of AOD from both satellite retrievals and model over East Asia are also consistent with the trend of SO2 emission in China, especially during the second half of the year, when sulfur contributes the largest fraction of AOD. The arrested growth in SO2 emissions since 2006 is also reflected in the decreasing trends of SO2 and SO42- concentrations, acid rain pH values and frequencies, and AOD over East Asia.

Lu, Z.; Streets, D. G.; Zhang, Q.; Wang, S.; Carmichael, G. R.; Cheng, Y. F.; Wei, C.; Chin, M.; Diehl, T.; Tan, Q.

2010-07-01

133

Sulfur cathodes with hydrogen reduced titanium dioxide inverse opal structure.  

PubMed

Sulfur is a cathode material for lithium-ion batteries with a high specific capacity of 1675 mAh/g. The rapid capacity fading, however, presents a significant challenge for the practical application of sulfur cathodes. Two major approaches that have been developed to improve the sulfur cathode performance include (a) fabricating nanostructured conductive matrix to physically encapsulate sulfur and (b) engineering chemical modification to enhance binding with polysulfides and, thus, to reduce their dissolution. Here, we report a three-dimensional (3D) electrode structure to achieve both sulfur physical encapsulation and polysulfides binding simultaneously. The electrode is based on hydrogen reduced TiO2 with an inverse opal structure that is highly conductive and robust toward electrochemical cycling. The relatively enclosed 3D structure provides an ideal architecture for sulfur and polysulfides confinement. The openings at the top surface allow sulfur infusion into the inverse opal structure. In addition, chemical tuning of the TiO2 composition through hydrogen reduction was shown to enhance the specific capacity and cyclability of the cathode. With such TiO2 encapsulated sulfur structure, the sulfur cathode could deliver a high specific capacity of ?1100 mAh/g in the beginning, with a reversible capacity of ?890 mAh/g after 200 cycles of charge/discharge at a C/5 rate. The Coulombic efficiency was also maintained at around 99.5% during cycling. The results showed that inverse opal structure of hydrogen reduced TiO2 represents an effective strategy in improving lithium sulfur batteries performance. PMID:24766547

Liang, Zheng; Zheng, Guangyuan; Li, Weiyang; Seh, Zhi Wei; Yao, Hongbin; Yan, Kai; Kong, Desheng; Cui, Yi

2014-05-27

134

Anomalous Emissions of Sulfur Dioxide and Seismicity of San Miguel Volcano, EL Salvador in October, 2006  

NASA Astrophysics Data System (ADS)

San Miguel (also known as Chaparrastique) volcano in eastern El Salvador is located 15 km southwest of the city of San Miguel. This volcano has erupted more than 30 times since 1699, with the last gas and ash emission on January 16, 2002. During 2006, San Miguel presented anomalous gas emissions and seismicity. In this work, the seismic parameters reported by SNET (Servicio Nacional de Estudios Territoriales de El Salvador) and the crater gas emissions measured by researchers of the University of El Salvador are compared. For the gas efflux, two types of measurements were done using the Mini-DOAS system (Galle et al., 2002): transects around the crater perimeter (~100 m) and transects following roads located between 5 and 10 km from the crater. Several measurements between October 2005 and May 2006 indicate that the sulfur dioxide efflux during quiet periods is around 20 ton/day. From May to June 2006, a progressive increase in fumarolic activity and noise from gas emissions were observed. From May to August 2006, the sulfur dioxide emissions increased to 60 ton/day. A seismic crisis started on October 9, 2006, increasing the RSAM from 10-20 to 208 on October 10, 2006. During this time, the sulfur dioxide efflux reached a maximum of 492 ton/day. This increase in sulfur dioxide efflux represents 25 times the basic emissions during the previous quiet period and 8 times the values observed from May to August 2006. The correlation coefficient between sulfur dioxide efflux and RSAM values during this period of time was 0.81, which is statistically significant at a level higher than 99.9% . These anomalous changes in seismicity and sulfur dioxide emissions at San Miguel volcano suggest a magmatic reactivation with an increase in the exsolution of magma volatiles, long period seismic events, and volcanic tremor.

Olmos, R.; Barahona, F.; Hernández, A.; Cartagena, R.; Henríquez, B.; López, D.; Cárdenas, C.; Galle, B.

2007-12-01

135

Fast-regenerable sulfur dioxide adsorbents for diesel engine emission control  

DOEpatents

Disclosed herein are sorbents and devices for controlling sulfur oxides emissions as well as systems including such sorbents and devices. Also disclosed are methods for making and using the disclosed sorbents, devices and systems. In one embodiment the disclosed sorbents can be conveniently regenerated, such as under normal exhaust stream from a combustion engine, particularly a diesel engine. Accordingly, also disclosed are combustion vehicles equipped with sulfur dioxide emission control devices.

Li, Liyu [Richland, WA; King, David L [Richland, WA

2011-03-15

136

Improved efficiency in the sulfur dioxide - Iodine hydrogen cycle through the use of magnesium oxide  

NASA Astrophysics Data System (ADS)

The reaction of iodine with dry magnesium oxide and magnesium sulfite hexahydrate was studied experimentally as a possible means of improving the efficiency of the sulfur dioxide-iodine cycle. When no extra water was introduced, the maximum product yield was 67% obtained at 423 K. With excess water vapor, a nonporous plug was formed which prevented complete reaction. In the second case, maximum yield was 62% measured at 423 K showing that added water does not increase reaction products. This reaction gives an alternate route for producing hydrogen from water via the sulfur dioxide-iodine process.

Mason, C. F. V.; Bowman, M. G.

137

Improved efficiency in the sulfur dioxide-iodine hydrogen cycle through the use of magnesium oxide  

SciTech Connect

The reaction of iodine with dry magnesium oxide and magnesium sulfite hexahydrate was studied experimentally as a possible means of improving the efficiency of the sulfur dioxide-iodine cycle. When no extra water was introduced, the maximum product yield was 67% obtained at 423 K. With excess water vapor, a nonporous plug was formed which prevented complete reaction. In the second case, maximum yield was 62% measured at 433 K showing that added water does not increase reaction products. This reaction gives an alternate route for producing hydrogen from water via the sulfur dioxide-iodine process.

Mason, C.F.V.; Bowman, M.G.

1981-01-01

138

Forage quality of western wheatgrass exposed to sulfur dioxide  

SciTech Connect

Effects of three exposure levels of SO/sub 2/ (55, 100, and 170 ..mu..m/sup -3/) on the nutritive value of western wheatgrass were investigated. Significant increases in plant sulfur content were observed, both with time and level of SO/sub 2/ exposure. Plant ash content paralled the trends observed for sulfur concentrations. Nitrogen concentrations in western wheatgrass were not affected by SO/sub 2/ treatments. The increased plant sulfur content and decreased N:S ratios across treatments did not significantly affect forage digestibility as measured by in vitro digestible dry matter.

Milchunas, D.G.; Lauenroth, W.K.; Dodd, J.L.

1981-07-01

139

Advanced byproduct recovery: Direct catalytic reduction of sulfur dioxide to elemental sulfur. Quarterly report, April 1--June 30, 1997  

SciTech Connect

The team of Arthur D. Little, Tufts University and Engelhard Corporation are conducting Phase 1 of a four and a half year, two-phase effort to develop and scale-up an advanced byproduct recovery technology that is a direct, single-stage, catalytic process for converting sulfur dioxide to elemental sulfur. This catalytic process reduces SO{sub 2} over a fluorite-type oxide (such as ceria and zirconia). The catalytic activity can be significantly promoted by active transition metals, such as copper. More than 95% elemental sulfur yield, corresponding to almost complete sulfur dioxide conversion, was obtained over a Cu-Ce-O oxide catalyst as part of an on-going DOE-sponsored, University Coal Research Program. This type of mixed metal oxide catalyst has stable activity, high selectivity for sulfur production, and is resistant to water and carbon dioxide poisoning. Tests with CO and CH{sub 4} reducing gases indicate that the catalyst has the potential for flexibility with regard to the composition of the reducing gas, making it attractive for utility use. The performance of the catalyst is consistently good over a range of SO{sub 2} inlet concentration (0.1 to 10%) indicating its flexibility in treating SO{sub 2} tail gases as well as high concentration streams. The principal objective of the Phase 1 program is to identify and evaluate the performance of a catalyst which is robust and flexible with regard to choice of reducing gas. In order to achieve this goal, the authors have planned a structured program including: Market/process/cost/evaluation; Lab-scale catalyst preparation/optimization studies; Lab-scale, bulk/supported catalyst kinetic studies; Bench-scale catalyst/process studies; and Utility review. Progress is reported from all three organizations.

NONE

1997-12-31

140

Improvement in the Capacity and Safety of Lithium/Inorganic Electrolyte Sulfur Dioxide Rechargeable Cells. Phase 2.  

National Technical Information Service (NTIS)

Our objective was to develop a prototype rechargeable lithium/sulfur dioxide/carbon cell, using practical AA size hardware, in which the electrolyte was to be a sulfur dioxide solution of lithium bromide or thiocyanate, together with a highly soluble coso...

A. P. Johnson C. R. Schlaikjer J. E. Torkelson M. D. Jones W. VanSchalkwijk

1990-01-01

141

Pulmonary Response to Threshold Levels of Sulfur Dioxide (1.0 ppm) and Ozone (0.3 ppm) (Journal Version).  

National Technical Information Service (NTIS)

The authors exposed 22 healthy adult non-smoking men for 2 hours to either filtered air, 1.0 ppm sulfur dioxide, 0.30 ppm ozone or the combination of 1.0 ppm sulfur dioxide plus 0.30 ppm ozone. It was hypothesized that exposure to near threshold concentra...

L. J. Folinsbee J. F. Bedi S. M. Horvath

1985-01-01

142

78 FR 47191 - Air Quality Designations for the 2010 Sulfur Dioxide (SO2) Primary National Ambient Air Quality...  

Federal Register 2010, 2011, 2012, 2013

...the 2010 Sulfur Dioxide (SO[bdi2]) Primary National Ambient Air Quality Standard...areas in the United States for the 2010 primary Sulfur Dioxide (SO 2 ) National Ambient...Administrator signed a final rule revising the primary SO 2 NAAQS on June 2, 2010....

2013-08-05

143

Effects of Ozone and Sulfur Dioxide on Forage and Range Species. Volume 1. On Growth and Partioning.  

National Technical Information Service (NTIS)

Tall fescue and red brome plants were grown from seed and planted in pots. Plants were exposed once per week for six hours to 0.2 ppm ozone, 0.2 ppm sulfur dioxide, 0.2 ppm ozone plus 0.2 ppm sulfur dioxide or a charcoal-filtered control in greenhouse fum...

V. B. Younger R. B. Flagler O. C. Taylor

1983-01-01

144

Statistical summary of air quality data for metropolitian Cleveland, Ohio, 1967 - 1972: Total suspended particulates, nitrogen dioxide, and sulfur dioxide  

NASA Technical Reports Server (NTRS)

Air-quality data for metropolitan Cleveland, Ohio, from 1967 through 1972 were collated and statistically analyzed. Total suspended particulates (TSP) departed from lognormal distribution in 1972. Nitrogen dioxide and sulfur dioxide, departed significantly from lognormal distributions in 1972. In Cleveland the Ohio standards were not met. However, the data indicate a general improvement in air quality. Unusually high precipitation (43% above the average in 1972) may be responsible in lowering these values from the 1971 levels. The mean values of TSP, NO2, and SO2 are 104, 191, and 83 microgram/cu m respectively.

King, R. B.; Neustadter, H. E.; Fordyce, J. S.; Burr, J. C., Jr.; Cornett, C. L.

1974-01-01

145

A study on carbothermal reduction of sulfur dioxide to elemental sulfur using oilsands fluid coke.  

PubMed

Experiments and reaction equilibrium calculations were carried out for the SO2 gas and oilsands fluid coke system. The goal was to develop a coke-based sulfur-producing flue gas desulfurization (SP-FGD) process that removes SO2 from flue gases and converts it into elemental sulfur. The conversion of SO2 to elemental sulfur proceeded efficiently at temperatures higher than 600 degrees C, and the sulfur yield reached a maximum (> 95%) at about 700 degrees C. An increase of temperature beyond 700 degrees C enhanced the reduction of product elemental sulfur, resulting in the formation of reduced sulfur species (COS and CS2), which lowered the sulfur yield at 900 degrees C to 90%. Although equilibrium calculations suggest that a lower temperature favors the conversion of SO2 as well as the yield of elemental sulfur, experiments showed no formation of elemental sulfur at 600 degrees C and below, likely due to hindered kinetics. Faster reduction of SO2 was observed at a higher temperature in the range of 700-1000 degrees C. A complete conversion of SO2 was achieved in about 8 s at 700 degrees C. Prolonging the product gas--coke contact, the yield of elemental sulfur decreased due to the formation of COS and CS2 while the SO2 conversion remained complete. Equilibrium calculations suggest that the ultimate yield of elemental sulfur maximizes at the C/SO2 ratio of 1, which represents the stoichiometry of SO2 + C-->CO2 + S. For the C/SO2 ratio < 1, equilibrium calculations predict elemental sulfur and CO2 being major products, suggesting that SO2 + C-->CO2 + S is the predominant reaction if SO2 is in excess. Experiments revealed that elemental sulfur and CO2 were only major products if the conversion of SO2 was incomplete, which is in agreement with the result of the equilibrium modeling. PMID:11349295

Bejarano, C A; Jia, C Q; Chung, K H

2001-02-15

146

ACID PRECIPITATION: EFFECTS OF SULFUR DIOXIDE AND SULFATE AEROSOL PARTICLES ON HUMAN HEALTH  

EPA Science Inventory

While human health impairment has been attributed to pollution by sulfur dioxide (SO2), data from inhalation studies in animals show that its oxidation products are more irritating. Population surveys in which suspended sulfate was a co-variant suggest that certain health paramet...

147

The Sulfur Dioxide Plume from the February 26, 2000 Eruption of Mt. Hekla, Iceland  

NASA Technical Reports Server (NTRS)

The February 2000 fissure eruption of Mt. Hekla, Iceland was captured in sulfur dioxide data from the Earth Probe TOMS. A special algorithm is used to discriminate sulfur dioxide from ozone. The eruption began at 18:19 GMT on February 26, 2000 and was first viewed by TOMS at 09:55 GMT on February 27. The volcanic cloud at that time appeared as a very long and narrow arc extending west from the volcano in southern Iceland, then north across Greenland, and finally east towards Norway. The cloud altitude was reported from aircraft sightings and data to be above 10 km. The circulation of a ridge located north of Iceland produced the large arc shaped cloud. As the eruption is non-explosive the high altitude cloud contains little ash. Almost all the ash from the eruption fell out locally across Iceland. By February 29, the sulfur dioxide cloud had drifted eastward in a band along the Barents Sea coast of Norway and Russia. The analysis includes an assessment of the initial sulfur dioxide content and its rate of conversion to sulfate.

Krueger, Arlin J.; Krotkov, N. A.; Einaudi, Franco (Technical Monitor)

2000-01-01

148

An assessment of spatial and temporal variation of sulfur dioxide levels over Istanbul, Turkey  

Microsoft Academic Search

Sulfur dioxide concentration levels are investigated in Istanbul to assess air pollution during the heating seasons in which the concentration of air pollutants reach high levels due to the consumption of low-quality fossil fuels. Results reveal that in the 1985–91 period there is an increasing trend in the concentrations of air pollutants. One reason for this increase is found to

M Tayanç

2000-01-01

149

Acid Precipitation: Effects of Sulfur Dioxide and Sulfate Aerosol Particles on Human Health.  

National Technical Information Service (NTIS)

While human health impairment has been attributed to pollution by sulfur dioxide (SO2), data from inhalation studies in animals show that its oxidation products are more irritating. Population surveys in which suspended sulfate was a co-variant suggest th...

D. L. Coffin J. H. Knelson

1976-01-01

150

Modification of the sulfur dioxide-iodine thermochemical hydrogen cycle with lanthanum sulfites and sulfates  

Microsoft Academic Search

Variable composition, insoluble dilanthanum oxide-sulfite-sulfate-hydrates were prepared by reaction of lanthanum dioxymonosulfate with aqueous sulfur dioxide. These compositions reacted with iodine to yield sulfate in the solid phase, and hydrogen iodide and water in the gas phase. The highest yield of hydrogen iodide measured was 32% at 660 K for a few seconds reaction time of iodine with a reactant

E. I. Onstott; M. G. Bowman; M. F. Michnovicz; C. M. Hollabaugh

1984-01-01

151

Reactions for improving efficiencies in thermochemical cycles related to the sulfur dioxide-iodine process  

Microsoft Academic Search

A modification of the sulfur dioxide iodine cycle which uses magnesium oxide, magnesium sulfite and magnesium iodide is examined with particular emphasis on decreasing the amount of water employed and thereby increasing the efficiency. The key reaction is that of iodine with magnesium oxide and magnesium sulfite hexahydrate with no additional water. This produces 77% of the total possible sulfate

C. F. V. Mason; M. G. Bowman

1982-01-01

152

Initial interaction of sulfur dioxide with water covered metal surfaces: An in situ IRAS study  

Microsoft Academic Search

Sulfur dioxide is considered to be one of the most important stimulators of atmospheric corrosion in outdoor environments and numerous investigations have been made to understand its role. Despite clear evidence of the corrosion accelerating effect of SOâ there is still a lack in detailed knowledge on a molecular level of how SOâ interacts with metal surfaces during conditions of

D. Persson; C. Leygraf

1995-01-01

153

SPONTANEOUSLY HYPERTENSIVE RATS ARE SUSCEPTIBLE TO AIRWAY DISEASE INDUCED BY SULFUR DIOXIDE  

EPA Science Inventory

Rodent models of chronic pulmonary diseases induced by sulfur dioxide (SO2), elastase or tobacco smoke have limited utility because of their lack of chronicity of inflammation, and they demonstrate limited sensitivity to a given experimental manipulation. We hypothesized that dis...

154

Tree-Ring Variation in Western Larch (Larix Occidentalis Nutt.) Exposed to Sulfur Dioxide Emissions.  

National Technical Information Service (NTIS)

Tree-ring analysis of western larch (Larix occidentialis Nutt) demonstrated both direct and indirect affects of sulfur dioxide emissions from the lead/zinc smelter at Trail, B.C. Tree cores were collected from 5 stands known to have been polluted and from...

C. A. Fox W. B. Kincaid T. H. Nash D. L. Young H. C. Fritts

1984-01-01

155

Sulfur Dioxide Emission Rates from Kilauea Volcano, Hawaii, an Update: 2002-2006.  

National Technical Information Service (NTIS)

Sulfur dioxide (SO2) emission rates from Kilauea Volcano were first measured by Stoiber and Malone (1975) and have been measured on a regular basis since 1979 (Greenland and others, 1985; Casadevall and others, 1987; Elias and others, 1998; Sutton and oth...

A. J. Sutton T. Elias

2007-01-01

156

COMBINED EFFECT OF SULFUR DIOXIDE AND OZONE ON BEAN AND TOBACCO PLANTS  

EPA Science Inventory

Plants of two cultivars of Phaseolus vulgaris and one cultivar of Nicotiana tabacum were exposed to a replicated series of concentrations of sulfur dioxide (SO2), ozone (03), and combinations of these two air pollutants for single four-hour periods. Experiments were performed in ...

157

PREVENTION REFERENCE MANUAL: CHEMICAL SPECIFIC. VOLUME 12. CONTROL OF ACCIDENTAL RELEASES OF SULFUR DIOXIDE  

EPA Science Inventory

The report discusses the control of accidental releases of sulfur dioxide (SO2) to the atmosphere. SO2 has an IDLH (immediately dangerous to life and health) concentration of 100 ppm, making it an acute toxic hazard. Reducing the risk associated with an accidental release of SO2 ...

158

Influence of volcanic sulfur dioxide on spectral UV irradiance as measured by Brewer Spectrophotometers  

Microsoft Academic Search

Spectra of UV irradiance measured by Brewer spectrophotometers at 13 stations in Japan and Canada have been examined to determine the effect of absorption by sulfur dioxide (SO2). A simple algorithm to estimate the total column amount of SO2 from global UV irradiance measurements has been developed. The algorithm which overestimates SO2 amounts at low altitudes is useful for identifying

Vitali E. Fioletov; Erik Griffioen; James B. Kerr; David I. Wardle; Osamu Uchino

1998-01-01

159

Influence of volcanic sulfur dioxide on spectral UV irradiance as measured by Brewer spectrophotometers  

Microsoft Academic Search

Spectra of UV irradiance measured by Brewer spectrophotometers at 13 stations in Japan and Canada have been examined to determine the effect of absorption by sulfur dioxide (SO2). A simple algorithm to estimate the total column amount of SO2 from global UV irradiance measurements has been developed. The algorithm which overestimates SO2 amounts at low altitudes is useful for identifying

Vitali E. Fioletov; Erik Griffioen; James B. Kerr; David I. Wardle; Osamu Uchino

1998-01-01

160

Final San Manuel Sulfur Dioxide Nonattainment Area State Implementation and Maintenance Plan.  

National Technical Information Service (NTIS)

This document includes an attainment demonstration and formal request to the United States Environmental Agency (EPA) to redesignate the San Manuel, Arizona area, a nonattainment area for sulfur dioxide SO(sub 2), to attainment for the health-based 24-hou...

2002-01-01

161

ENHANCEMENT OF REACTIVITY IN SURFACTANT-MODIFIED SORBENTS FOR SULFUR DIOXIDE CONTROL  

EPA Science Inventory

Injection of calcium-based sorbents into the postflame zone of utility boilers is capable of achieving sulfur dioxide (SO2) captures of 50-60% at a stoichiometry of 2. Calcium hydroxide [Ca(OH)2] appears to be the most effective commercially available sorbent. Recent attempts to ...

162

CALCINATION AND SINTERING OF SORBENTS DURING BOILER INJECTION FOR DRY SULFUR DIOXIDE CONTROL  

EPA Science Inventory

The paper discusses the calcination and sintering of sorbents during boiler injection for dry sulfur dioxide (S02) control, with emphasis on calcium hydroxide--Ca(OH)2--because of its superior reactivity with S02 and its wide commercial availability. Calcination and sintering are...

163

OXYGEN ISOTOPES IN ATMOSPHERIC SULFATES, SULFUR DIOXIDE, AND WATER VAPORS FIELD MEASUREMENTS, JULY 1975  

EPA Science Inventory

Oxygen isotope ratios were determined for atmospheric samples of sulfate aerosols, sulfur dioxide, and water vapor collected simultaneously during a six-day period in July, 1975, at St. Louis, MO; Auburn, IL; and Glasgow, IL. The collection sites were located about 100km apart. C...

164

Acute effects of sulfur dioxide exposure on the middle ear mucosa  

SciTech Connect

A variety of atmospheric pollutants are known to depress mucociliary function in the respiratory system. Since the mucociliary function in the middle ear is similar, and the middle ear may be invaded by atmospheric pollutants, we decided to investigate the possible contribution of sulfur dioxide to middle ear effusion. Guinea pigs were exposed for 24 hours to 300 ppm of sulfur dioxide or air. Immediately after exposure, ciliary activity and epithelial structure were examined close to the tympanic orifice (proximal site) and more distal to it (distal site). In the animals exposed to sulfur dioxide, no effusion was found in the tympanic cavity. Ciliary activity was reduced only in the distal site. Electron microscopy demonstrated hypersecretion in the proximal site and severe pathologic changes in the distal site. Although the normally functioning cilia in the proximal site may prevent retention of surplus secretions in the ear, sulfur dioxide may promote middle ear effusion when combined with other detrimental factors, because it stimulates mucus secretion in the proximal site and impairs ciliary function in the distal site.

Ohashi, Y.; Nakai, Y.; Ikeoka, H.; Koshimo, H.; Esaki, Y.

1989-04-01

165

Adsorption-chemical method of determining hydrogen sulfide and sulfur dioxide in gas mixtures  

Microsoft Academic Search

mixtures with other gases [5-8] are associated with the use of various aqueous solutions (specifically sodium arsenate in water), which results in a low accuracy in the analyses because of the good solubility of the sample gases in water. The presence of CO z interferes with the determination of sulfur dioxide and hydrogen sulfide. In addition, much time and a

M. A. Ryashentseva; Yu. A. Afanas'eva

1967-01-01

166

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

167

EQUILIBRIUM PARTIAL PRESSURE OF SULFUR DIOXIDE IN ALKALINE SCRUBBING PROCESSES  

EPA Science Inventory

The report gives results of IERL-RTP in-house studies in which equilibrium partial pressure of SO2 was measured as a function of pH, temperature, and concentration of sulfur (IV) on various scrubber liquors. These studies were done for potassium-, sodium-, and citrate-based scrub...

168

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

Code of Federal Regulations, 2013 CFR

...remove sulfur oxides. (iii) Fossil fuel means natural gas, refinery...from such materials. (iv) Fossil fuel-fired steam generating unit...used in the process of burning fossil fuel for the purpose of producing...

2013-07-01

169

Sulfur Dioxide Flux into Leaves of Geranium carolinianum L. 1  

PubMed Central

The concurrent exchange of SO2 and H2O vapor between the atmosphere and foliage of Geranium carolinianum was investigated using a whole-plant gas exchange chamber. Total leaf flux of SO2 was partitioned into leaf surface and internal fractions. The emission rate of SO2-induced H2S was measured to develop a net leaf budget for atmospherically derived sulfur. Stomatal resistance to SO2 flux was estimated by two techniques: (a) RsSO2? from SO2 data using analog modeling techniques and (b) RsSO2 from analogy to H2O (i.e. 1.89 RsH2o). The emission of H2S was positively correlated with the rate of SO2 flux into the leaf interior. An accounting of the simultaneous, bidirectional flux of gaseous sulfur compounds during pollutant exposure showed that sulfur accumulation in the leaf interior of G. carolinianum was 7 to 15% lower than that estimated solely from mass-balance calculations of SO2 flux data (i.e. ignoring H2S emissions). The esimate of stomatal resistance to pollutant flux from the SO2 data (RsSO2?) was consistently less than the simultaneous estimate derived from analogy to H2O vapor (RsSO2). The resultant of RsSO2? — RsSO2, which was always negative, is indicative of a residual resistance to SO2 flux into the leaf interior. On a comparative basis, SO2 molecules experienced less pathway resistance to diffusion than effluxing H2O molecules. It is proposed that the SO2:H2O path length ratio is less than unity, as a consequence of the pollutant's high water solubility and unique chemical reactivity in solution. Thus, the diffusive paths for H2O and SO2 in G. carolinianum are not completely synonymous.

Taylor, George E.; Tingey, David T.

1983-01-01

170

Advection of sulfur dioxide over the western Atlantic Ocean during CITE 3  

SciTech Connect

During the NASA Chemical Instrumentation Test and Evaluation 3 sulfur intercomparison over the western Atlantic Ocean, five techniques for the determination of sulfur dioxide were evaluated. The response times of the techniques varied from 3 to 30 min. Based on the ensemble of measurements reported, it was clear that advection of SO2 from the North American continent occurred in the boundary layer (altitude less than 1 km) with only one exception. The vertical distribution of SO2 above the boundary layer for the northern and southern Atlantic Ocean was remarkably similar duing this experiment.

Thornton, D.C.; Bandy, A.R.; Beltz, N.; Driedger, A.R. III; Ferek, R. [Drexel Univ., Philadelphia, PA (United States)]|[Univ. of Frankfurt, Frankfurt (Germany)]|[Univ. of Washington, Seatlle, WA (United States)

1993-12-01

171

Theoretical study of formic acid-sulfur dioxide dimers.  

PubMed

We report the first theoretical study of noncovalent and covalent interactions in formic acid (FA)-SO(2) complexes. Using ab initio and DFT model chemistries, five stable noncovalent complexes were identified, as well as a covalent adduct, formic sulfurous anhydride HOSO(2)CHO. syn-FA is predicted to form two nonplanar bidentate complexes with SO(2): the more stable one contains a normal hydrogen bond donated by OH, and the less stable one contains a blue-shifted hydrogen bond donated by CH. Both are stabilized by charge transfer from FA to SO(2). anti-FA forms three planar complexes of nearly equal energy containing OH-to-SO(2) hydrogen bonds. Formic sulfurous anhydride forms via an endothermic concerted cycloaddition. Natural bond orbital analysis showed that the bidentate SO(2)-FA complexes are stabilized by n ? ?* donation from FA to SO(2), and back-donation from SO(2) n and ?* orbitals into FA ?(OH)* or ?(CH)* orbitals. The bidentate formic acid-SO(2) complex that contains an O-H···O hydrogen bond is more stable than the similar nitric acid-SO(2) complex. The latter contains a stronger hydrogen bond but shows no O?S charge transfer interaction. PMID:21117658

Keller, John W; Harrod, Bronwyn L; Chowdhury, Sifat A

2010-12-23

172

40 CFR Appendix A to Part 50 - Reference Method for the Determination of Sulfur Dioxide in the Atmosphere (Pararosaniline Method)  

Code of Federal Regulations, 2010 CFR

...and S. A. Frey. Spectrophotometric Determination of Atmospheric Sulfur Dioxide. Anal. Chem., 39: 1709, 1967. 11. Pate, J. B., B. E. Ammons, G. A. Swanson, and J. P. Lodge, Jr. Nitrite Interference in Spectrophotometric...

1996-07-01

173

40 CFR Appendix A to Part 50 - Reference Method for the Determination of Sulfur Dioxide in the Atmosphere (Pararosaniline Method)  

Code of Federal Regulations, 2010 CFR

...and S. A. Frey. Spectrophotometric Determination of Atmospheric Sulfur Dioxide. Anal. Chem., 39: 1709, 1967. 11. Pate, J. B., B. E. Ammons, G. A. Swanson, and J. P. Lodge, Jr. Nitrite Interference in Spectrophotometric...

1997-07-01

174

Improved efficiency in thermochemical hydrogen cycles through decreasing the use of solvent water. Consideration of the sulfur dioxide: iodine cycle  

Microsoft Academic Search

This paper considers the relationship between evaporation and efficiency and examines experimentally an adaptation of the sulfur dioxide-iodine cycle where little water needs to be evaporated or condensed.

C. F. V. Mason; M. G. Bowman

1982-01-01

175

Control of Air Pollution Emissions from Molybdenum Roasting. Volume 2. Alternatives for Control of Weak Sulfur Dioxide Emissions.  

National Technical Information Service (NTIS)

This report covers the second phase of a three phase effort evaluating (1) characterization of particulate control of a molybdenum sulfide roasters, (2) assessment of sulfur dioxide abatement alternatives for nonferrous smelting and, in particular, for mo...

N. H. Masarky R. D. Delleney K. Schwitzgebel T. P. Nelson R. L. Glover

1983-01-01

176

EFFECT OF SULFUR DIOXIDE ON THE FORMATION MECHANISM OF POLYCHLORINATED DIBENZODIOXIN AND DIBENZOFURAN IN MUNICIPAL WASTE COMBUSTORS  

EPA Science Inventory

The effect of sulfur dioxide on the formation mechanism of polychlorinated dibenzodioxin (PCDD) and polychlorinated dibenzofuran (PCDF) in the postcombustion, downstream region (500-300 °C) of a municipal waste combustor (MWC) was investigated. Laboratory experiments simulating t...

177

Sulfuric Acid Nucleation with NH3, Methyl, Dimethyl, and Trimethyl Amines  

NASA Astrophysics Data System (ADS)

Nucleation of particles from sulfuric acid, water, and nitrogen base molecules was studied within a cylindrical flow reactor. The particles formed from these vapors were detected with a nano Mobility Particle Sizer coupled to a Diethylene Glycol Ultrafine Condensation Particle Counter. The effects of ammonia and small alkyl amines on particle formation with sulfuric acid vapor were very large. Enhancements of particle numbers by factors of thousands to millions indicates that these species have powerful effects on nucleation of sulfuric acid molecules. Power dependencies for particle numbers on sulfuric acid and nitrogen bases elucidates the chemical content of the critical clusters and this helps to shed light on the nucleation mechanisms. The details of the particle detection efficiencies, information on the extent of particle growth, and independently determined cluster thermodynamics help to verify these results and to extrapolate them to atmospheric conditions.

Hanson, D. R.; Volz, K.; Glasoe, W.; Panta, B.

2013-12-01

178

Atmospheric oxidation of sulfur dioxide as viewed from power plant and smelter plume studies  

SciTech Connect

An overview is presented of significant historical, recent, and new power plant and smelter plume studies which have been directed at understanding the atmospheric oxidation of sulfur dioxide. It can be concluded that the average rate of oxidation of sulfur dioxide in plumes entering into and mixing with clean air is generally less than 1% per hour but with polluted urban air the rate can be at least twice as fast. In addition, a diurnal variation in the rate is sometimes observed that is near zero at night and approximately 3% during midday. Although there is a tendency to select the homogeneous over the heterogeneous mechanism as the dominant pathway for the oxidation, the basis for choice is not definitive and most likely both mechanisms are at times operative. Suggestions are advanced for new and important studies that can be performed with technologies just becoming available.

Newman, L

1980-01-01

179

Reactions between calcium oxide and flue gas containing sulfur dioxide at lower temperatures  

SciTech Connect

An experimental study has been performed of the reactions occurring when the reactive particles of calcium oxide are exposed to sulfur dioxide bearing flue gas. Using a differential, fixed-bed reactor, kinetic measurements have been made in the temperature range of 170 and 580C. A relatively simple correlation based on the amassed data has been proposed. This correlation allows the estimation of the reaction rate as a function of temperature, conversion of the solids and concentration of sulfur dioxide in the gas phase. The proposed rate law equation makes it possible to predict in a straightforward manner the rate of sorption which would be required to design the performance of a desulfurization unit.

Hartman, M.; Trnka, O. (Czech Academy of Sciences, Prague (Czechoslovakia))

1993-04-01

180

Protective effects of seabuckthorn seed oil on mouse injury induced by sulfur dioxide inhalation.  

PubMed

Sulfur dioxide (SO2) is a common but important air pollutant. Micronuclei (MN) in the polychromatic erythrocytes (PCE) of mouse bone marrow and the ratio between organ and body weight of treatment mouse were determined and analyzed in vivo in order to study injury of sulfur dioxide inhalation on organs and germ plasm of mouse as well as protective effect of seabuckthorn seed oil against this injury. It was showed that SO2 inhalation induced the change of the ratio between organ and body of mouse organs, such as liver, lung, kidney, and spleen, and a significant increase of number of MNPCE, while seabuckthorn seed oil offered a protection against such injury. PMID:12928980

Ruan, Aidong; Min, Hang; Meng, Ziqiang; Lü, Zhenmei

2003-09-01

181

Sulfur dioxide emission rates from K?lauea Volcano, Hawai‘i, 2007–2010  

USGS Publications Warehouse

K?lauea Volcano has one of the longest running volcanic sulfur dioxide (SO2) emission rate databases on record. Sulfur dioxide emission rates from K?lauea Volcano were first measured by Stoiber and Malone (1975) and have been measured on a regular basis since 1979 (Elias and Sutton, 2007, and references within). Compilations of SO2 emission-rate and wind-vector data from 1979 through 2006 are available on the USGS Web site (Elias and others, 1998; Elias and Sutton, 2002; Elias and Sutton, 2007). This report updates the database, documents the changes in data collection and processing methods, and highlights how SO2 emissions have varied with eruptive activity at K?lauea Volcano for the interval 2007–2010.

Elias, T.; Sutton, A. J.

2012-01-01

182

Utilization of Dimethyl Sulfide as a Sulfur Source with the Aid of Light by Marinobacterium sp. Strain DMS-S1  

PubMed Central

Strain DMS-S1 isolated from seawater was able to utilize dimethyl sulfide (DMS) as a sulfur source only in the presence of light in a sulfur-lacking medium. Phylogenetic analysis based on 16S ribosomal DNA genes indicated that the strain was closely related to Marinobacterium georgiense. The strain produced dimethyl sulfoxide (DMSO), which was a main metabolite, and small amounts of formate and formaldehyde when grown on DMS as the sole sulfur source. The cells of the strain grown with succinate as a carbon source were able to use methyl mercaptan or methanesulfonate besides DMS but not DMSO or dimethyl sulfone as a sole sulfur source. DMS was transformed to DMSO primarily at wavelengths between 380 and 480 nm by heat-stable photosensitizers released by the strain. DMS was also degraded to formaldehyde in the presence of light by unidentified heat-stable factors released by the strain, and it appeared that strain DMS-S1 used the degradation products, which should be sulfite, sulfate, or methanesulfonate, as sulfur sources.

Fuse, Hiroyuki; Takimura, Osamu; Murakami, Katsuji; Yamaoka, Yukiho; Omori, Toshio

2000-01-01

183

Direct linkage between dimethyl sulfide production and microzooplankton grazing, resulting from prey composition change under high partial pressure of carbon dioxide conditions.  

PubMed

Oceanic dimethyl sulfide (DMS) is the enzymatic cleavage product of the algal metabolite dimethylsulfoniopropionate (DMSP) and is the most abundant form of sulfur released into the atmosphere. To investigate the effects of two emerging environmental threats (ocean acidification and warming) on marine DMS production, we performed a large-scale perturbation experiment in a coastal environment. At both ambient temperature and ? 2 °C warmer, an increase in partial pressure of carbon dioxide (pCO2) in seawater (160-830 ppmv pCO2) favored the growth of large diatoms, which outcompeted other phytoplankton species in a natural phytoplankton assemblage and reduced the growth rate of smaller, DMSP-rich phototrophic dinoflagellates. This decreased the grazing rate of heterotrophic dinoflagellates (ubiquitous micrograzers), resulting in reduced DMS production via grazing activity. Both the magnitude and sign of the effect of pCO2 on possible future oceanic DMS production were strongly linked to pCO2-induced alterations to the phytoplankton community and the cellular DMSP content of the dominant species and its association with micrograzers. PMID:24724561

Park, Ki-Tae; Lee, Kitack; Shin, Kyoungsoon; Yang, Eun Jin; Hyun, Bonggil; Kim, Ja-Myung; Noh, Jae Hoon; Kim, Miok; Kong, Bokyung; Choi, Dong Han; Choi, Su-Jin; Jang, Pung-Guk; Jeong, Hae Jin

2014-05-01

184

Improvement in the capacity and safety of lithium\\/inorganic electrolyte sulfur dioxide rechargeable cells, phase 2  

Microsoft Academic Search

The objective was to develop a prototype rechargeable lithium\\/sulfur dioxide\\/carbon cell, using practical AA size hardware, in which the electrolyte was to be a sulfur dioxide solution of lithium bromide or thiocyanate, together with a highly soluble cosolute, a second non-lithium salt of the same anion. The cosolute was intended to replace the organic cosolvents familiar from the primary cells,

Carl R. Schlaikjer; Medlinda D. Jones; Arden P. Johnson; James E. Torkelson; Walter Vanschalkwijk

1990-01-01

185

Sulfur dioxide abatement costs and compliance with health-based standards: the case of copper smelters  

Microsoft Academic Search

This paper estimates the cost of the abatement of sulfur dioxide (SO2) for three copper smelters operating in Chile. It analyses compliance with emission goals and with the atmospheric health-based SO2 and breathable particle standards. The smelters are Chuquicamata, belonging to the State-owned company, Codelco; and Hernán Videla Lira and Ventanas belonging to ENAMI, the national mining company, also owned

Gustavo Lagos; José Miguel Lehuedé; Marcelo And??a

2001-01-01

186

Correcting satellite-based infrared sulfur dioxide retrievals for the presence of silicate ash  

Microsoft Academic Search

Previous studies have suggested that the presence of silicate ash may cause the 8.6-mum sulfur dioxide (SO2) retrieval to overestimate total column abundances and contribute to variations between ultraviolet and 8.6-mum SO2 estimates. Tested here is a volcanic aerosol forward model which allows the determination of transmission spectra. The forward model is embedded into a three-layer atmospheric radiative transfer model,

C. S. Kearney; I. M. Watson

2009-01-01

187

Sulfur dioxide molecule sensors based on zigzag graphene nanoribbons with and without Cr dopant  

NASA Astrophysics Data System (ADS)

Structure, electronic, and transport properties of sulfur dioxide (SO2) molecule adsorbed on pure and Cr doped zigzag graphene nanoribbons (ZGNRs) are investigated by means of first principle density functional theory and nonequilibrium Green's function computations. It is found that Cr doped ZGNR is more sensitive to SO2 molecule than pure ZGNR. The pure ZGNRs with and without SO2 molecule show similar I-V curves, but the current of Cr doped ZGNR will significant increase after SO2 molecule adsorption.

Shao, Li; Chen, Guangde; Ye, Honggang; Niu, Haibo; Wu, Yelong; Zhu, Youzhang; Ding, Bingjun

2014-01-01

188

The GOES-R Approach to Imager Based Sulfur Dioxide Detection  

Microsoft Academic Search

An automated sulfur dioxide (SO2) detection algorithm designed for the Advanced Baseline Imager (ABI) on the next generation of Geostationary Operational Environmental Satellites (GOES-R) is described. SO2 is present in many volcanic eruptions and may present a danger to aircraft, so the ability to identify SO2 clouds is important. This algorithm utilizes infrared SO2 absorption bands and cloud microphysical properties

A. C. Parker; M. J. Pavolonis

2009-01-01

189

Rate of sulfur dioxide oxidation in aqueous suspensions of calcium and magnesium carbonates  

Microsoft Academic Search

Determinations of the quantitative dependence of the rate of sulfur dioxide oxidation in aqueous suspensions of calcium and magnesium carbontes on the temperature, oxygen concentration in the gas, rate of mass transfer in the liquid and gaseous phases, and the presence of catalytic additives showed that increase of the temperature from 40 to 80°C in the bubbling regime (w\\/sub g\\/

E. A. Orlov; B. A. Kopylev; N. N. Treushchenko; G. V. Belchenko

1980-01-01

190

Association of Very Low Birth Weight with Exposures to Environmental Sulfur Dioxide and Total Suspended Particulates  

Microsoft Academic Search

This paper presents results of a population-based case-control study of the association between maternal exposures to environmental sulfur dioxide and total suspended particulates (TSP) and risk for having a very low birth weight (VLBW) baby, i.e., one weighing less than 1,500 g at birth. The study, which took place between April 1,1986 and March 30,1988, comprised 143 mothers of VLBW

J. Felix Rogers; Shirley J. Thompson; Cheryl L. Addy; Robert E. McKeown; David J. Cowen; Pierre Decoufle

191

Studies on the deactivation of NO x storage-reduction catalysts by sulfur dioxide  

Microsoft Academic Search

The interaction of sulfur dioxide with a commercial NOx storage-reduction catalyst (NSR) has been investigated using in situ IR and X-ray absorption spectroscopy. Two pathways of catalyst deactivation by SO2 were identified. Under lean conditions (exposure to SO2 and O2) at 350°C the storage component forms barium sulfates, which transform from surface to hardly reducible bulk sulfate species. The irreversible

Ch. Sedlmair; K. Seshan; A. Jentys; J. A. Lercher

2002-01-01

192

Removal of sulfur dioxide and formation of sulfate aerosol in Tokyo  

Microsoft Academic Search

Ground-based in situ measurements of sulfur dioxide (SO2) and submicron sulfate aerosol (SO4 2-) together with carbon monoxide (CO) were conducted at an urban site in Tokyo, Japan from spring 2003 to winter 2004. The observed concentrations of SO2 were affected dominantly by anthropogenic emissions (for example, manufacturing industries) in source areas, while small fraction of the data (<30%) was

T. Miyakawa; N. Takegawa; Y. Kondo

2007-01-01

193

Removal of sulfur dioxide and formation of sulfate aerosol in Tokyo  

Microsoft Academic Search

Ground-based in situ measurements of sulfur dioxide (SO2) and submicron sulfate aerosol (SO42?) together with carbon monoxide (CO) were conducted at an urban site in Tokyo, Japan from spring 2003 to winter 2004. The observed concentrations of SO2 were affected dominantly by anthropogenic emissions (for example, manufacturing industries) in source areas, while small fraction of the data (<30%) was affected

T. Miyakawa; N. Takegawa; Y. Kondo

2007-01-01

194

Considerations in the use and handling of lithium-sulfur dioxide batteries  

NASA Astrophysics Data System (ADS)

Plans to utilize lithium-sulfur dioxide batteries in the Army and development efforts in this field are discussed. These batteries are characterized by high energy density, high power density as compared with other primary batteries, and exceptional low temperature performance, yielding at -40 C approximately 40% of their 25 C capacity. The discussion focuses on the following areas: safety, transportation, storage, use, battery design, and disposal.

Reiss, E. H., Jr.

195

On the Retrieval of Volcanic Sulfur Dioxide Emissions from GOME Backscatter Measurements  

Microsoft Academic Search

We focus on the retrieval of volcanic sulfur dioxide (SO2) emissions from an analysis of atmospheric UV backscatter spectra obtained by the Global Ozone Monitoring Experiment (GOME) spectrometer on board the ESA European Remote Sensing Satellite (ERS-2). Here, the last major eruptions of Mt. Etna on Sicily (Italy) in July\\/August 2001 and October\\/November 2002 provided an excellent opportunity to study

W. Thomas; T. Erbertseder; T. Ruppert; M. Van Roozendael; J. Verdebout; D. Balis; C. Meleti; C. Zerefos

2005-01-01

196

Long-range transport of sulfur dioxide in the central Pacific  

Microsoft Academic Search

(1) Long-range transport of sulfur dioxide (SO2) from east Asia to the central North Pacific troposphere was observed on transit flights during the NASA Transport and Chemical Evolution over the Pacific mission. A series of SO2-enhanced layers above the boundary layer was observed during these flights. The significant features included enhanced SO2 layers associated with low water vapor and low

Fang Huang Tu; Donald C. Thornton; Alan R. Bandy; Gregory R. Carmichael; Youhua Tang; K. Lee Thornhill; Glenn W. Sachse; Donald R. Blake

2004-01-01

197

Vertical distribution of dimethylsulfide, sulfur dioxide, aerosol ions, and radon over the Northeast Pacific Ocean  

Microsoft Academic Search

Dimethylsulfide (DMS), sulfur dioxide (SO2), methanesulfonate (MSA), nonsea-salt sulfate (nss-SO42-), sodium (Na+), ammonium (NH4+), and nitrate (NO3-) were determined in samples collected by aircraft over the open ocean in postfrontal maritime air masses off the northwest coast of the United States (3–12 May 1985). Measurements of radon daughter concentrations and isentropic trajectory calculations suggested that these air masses had been

M. O. Andreae; H. Berresheim; T. W. Andreae; M. A. Kritz; T. S. Bates; J. T. Merrill

1988-01-01

198

Kinetic-energy release and intercharge distance of the sulfur dioxide dication (SO 2 2+)  

Microsoft Academic Search

The kinetic-energy release distributions (KERDs) of the fragment ion pairs (O+ + SO+ and O+ + S+) produced in dissociative double photoionization of sulfur dioxide have been determined by analyzing the photoion-photoion coincidence spectra measured in the energy region of 37–130 eV by use of a time-of-flight mass spectrometer and synchrotron radiation. It should be noted that the KERDs obtained

Toshio Masuoka

2001-01-01

199

Lithium\\/sulfur dioxide rechargeable cells with cosolute or with tetrachloroaluminate electrolytes  

Microsoft Academic Search

Lithium salts ordinarily slightly soluble in liquid sulfur dioxide may be made substantially soluble by the addition of soluble nonlithium salts, which apparently serve to increase the dielectric constant of the solution. Examples include KSCN\\/LiSCN and CsBr\\/LiBr. The chemical design allows the construction of cells without the need for organic cosolvents. The resistance to capacity fading in Li\\/SO2\\/carbon cells with

C. R. Schlaikjer; M. D. Jones; J. E. Torkelson; A. P. Johnson

1990-01-01

200

Advanced rechargeable lithium\\/sulfur dioxide cell. Final report, Sep 88Feb 91  

Microsoft Academic Search

The electrochemical performance and safety of the rechargeable lithium sulfur dioxide system has been investigated in laboratory cells and in high rate D cells. Small design and active materials were optimized to that cathode utilization of 1.6Ah\\/gram of carbon and 0.19Ah\\/cm3 of cathode were achieved with 100-200 cycles. Discharge and charge of cells at temperatures down to -30 C were

R. C. McDonald; P. Harris; F. Goebel; S. Hossain; R. Vierra

1991-01-01

201

Reactions of sulfur dioxide with pentaaquoorganochromium(III) complexes and trispolypyridinechromium(II) complexes  

Microsoft Academic Search

Chapter I describes the kinetics and mechanism of the reaction between sulfur dioxide and (HâO)âCrR\\/sup 2 +\\/ complexes. Parallels between this reaction and other electrophilic reactions of the (HâO)âCrR\\/sup 2 +\\/ complexes are drawn. The occurrence of two types of inorganic products is explained. Chapter II describes the production of *Cr(NN)â\\/sup 3 +\\/ via photochemical methods, the reductive quenching of

1988-01-01

202

Responses to sulfur dioxide and exercise by medication-depend asthmatics: Effect of varying medication levels  

Microsoft Academic Search

Twenty-one volunteers with moderate to severe asthma were exposed to sulfur dioxide (SOâ) at concentrations of O (control), 0.3, and 0.6 ppm in each of three medication states: (1) low (much of their usual asthma medication withheld), (2) normal (each subject on his own usual medication schedule), and (3) high (usual medication supplemented by inhaled metaproterenol before exposure). Theophylline, the

W. S. Linn; D. A. Shamoo; R. C. Peng; K. W. Clark; E. L. Avol; J. D. Hackney

2009-01-01

203

Responses to Sulfur Dioxide and Exercise by Medication-Dependent Asthmatics: Effect of Varying Medication Levels  

Microsoft Academic Search

Twenty-one volunteers with moderate to severe asthma were exposed to sulfur dioxide (SO2) at concentrations of 0 (control), 0.3, and 0.6 ppm in each of three medication states: (1) low (much of their usual asthma medication withheld), (2) normal (each subject on his own usual medication schedule), and (3) high (usual medication supplemented by inhaled metaproterenol before exposure). Theophylline, the

William S. Linn; Deborah A. Shamoo; Ru-Chuan Peng; Kenneth W. Clark; Edward L. Avol; Jack D. Hackney

1990-01-01

204

Effects of sulfur-dioxide and selected nutrient solutions upon western wheatgrass  

SciTech Connect

Sulfur dioxide is a key component of emissions from coal burning power plants. The effect of SO/sub 2/ upon dominant vegetation in the northern mixed prairie, an area in which production and burning of coal are expected to expand, is of considerable importance. Western wheatgrass plants (Agropyron smithii Rydb.) were maintained in nutrient solutions and exposed to different atmoshperic concentrations of SO/sub 2/ and root medium concentrations of sulfate (SO/sub 4/=) in field experiments. Plants were analyzed at three levels of organization: segments of leaf blades, fully expanded leaf blades and tillers. There were substantial gradients of increasing sulfur concentration from the bases to the tips of individual leaf blades. There was also a general increase in sulfur concentration from the youngest to the oldest leaf blade. Differences in sulfur concentration of leaf blade segments and leaf blades were not strongly related to SO/sub 2/ and demonstrates recognizable yet variable patterns of sulfur distribution. The objective of the laboratory experiment was to determine the effect of sulfur nutrition on growth of western wheatgrass. Growth was only minimally affected by three nutrient solution concentrations of SO/sub 4/ = (0 mM, 2 mM, and 4mM). It was concluded that the burning of coal and the maintenance of quality grassland dominated by western wheatgrass are compatible.

Bicak, C.J.

1982-01-01

205

Sorption of ozone and sulfur dioxide by petunia leaves  

SciTech Connect

Shoots of three cultivars of Petunia hybrida Vilm. of differing ozone (O/sub 3/) and sulphur dioxide (SO/sub 2/) sensitivity were exposed to O/sub 3/ and SO/sub 2/ in closed chambers for observation of pollutant absorption through the stomates and adsorption by leaf surfaces. The cultivar least sensitive to injury, 'Capri', absorbed the least ozone or SO/sub 2/ but absorbed the most. The sensitive 'White Cascade' had the opposite sorption pattern. Absorption of the individual gases was generally less from the mixture, whereas adsorption rates were similar whether the gases were supplied singly or in mixture. The existence of substantial differences in surface adsorption could introduce error in measurements of pollutant absorption by leaves.

Elkiey, T.; Ormrod, D.P.

1980-01-01

206

Analysis of simultaneous diffusion and chemical reaction in the calcium oxide-sulfur dioxide system  

SciTech Connect

There has been significant interest in the reaction between calcium oxide and sulfur dioxide because of its application in the reduction of gaseous sulfur emissions resulting from coal combustion by dry scrubbing and in fluidized bed combustion. This study includes a theoretical and experimental effort to study this reaction. A model is proposed which considers the important diffusion and reaction steps that are important in the sulfation of calcined limestone. The model describes the reacting solid as a sphere made up of randomly-oriented open pores. The macroscopic properties of the solid are obtained by integrating over the entire pore size distribution. The evolution of the pore size distribution is followed by use of a population balance. The predictions of this model are compared to kinetic data obtained using a thermogravimetric analyzer (TGA). Data obtained by the author and others show excellent agreement with the model. The predicted penetration of the sulfur into the reacting pellet is in qualitative agreement with results obtained with a scanning electron microscope. From estimates of the surface reaction rate constants it was determined that the rate controlling step was identical in the presence or absence of oxygen. Finally the results of experiments to study the effect of temperature on the reaction between sulfur dioxide and calcium oxide in lignite ash and limestone are presented. Four different lignite ashes and two different limestones were studied. Similar trends of decreasing total conversion with increasing temperature were observed, but it was not clear that these trends have the same causes.

Christman, P.G.

1981-01-01

207

High carbon dioxide solubilities in imidazolium-based ionic liquids and in poly(ethylene glycol) dimethyl ether.  

PubMed

This work is focused on the possible capture of carbon dioxide using ionic liquids (ILs). Such solvents are gaining special attention because the efficiency of many processes can be enhanced by the judicious manipulation of their properties. The absorption of greenhouse gases can be enhanced by the basic character of the IL. In this work, these characteristics are evaluated through the study of the gas-liquid equilibrium of four imidazolium-based ILs: 1-butyl-3-methylimidazolium tetrafluoroborate [BMIM][BF(4)], 1-butyl-3-methylimidazolium thiocyanate [BMIM][SCN], 1,3-dimethylimidazolium methylphosphonate [DMIM][MP], and 1,3-diethoxyimidazolium bis(trifluoromethylsulfonyl)imide [(ETO)(2)IM][Tf(2)N] with CO(2) at temperatures up to 373 K and pressures up to 300 bar. Solubility of carbon dioxide in poly(ethylene glycol) dimethyl ether, component of selexol, was also measured to evaluate the capture's efficiency of ionic liquids. Experimental data indicate that 67 to 123 g of CO(2) can be absorbed per kg of ionic liquid and 198 g per kg of poly(ethylene glycol) dimethyl ether. PMID:20853857

Revelli, Anne-Laure; Mutelet, Fabrice; Jaubert, Jean-Noël

2010-10-14

208

Collaborative Study of Method for the Determination of Sulfur Dioxide Emissions from Stationary Sources (Fossil-Fuel Fired Steam Generators).  

National Technical Information Service (NTIS)

A collaborative study has been performed on Method 6 promulgated by EPA for determining the concentration of sulfur dioxide emissions from stationary sources. Method 6 specified the extraction of a gas sample from the stack, the separation of the sulfur d...

H. F. Hamil D. E. Camann

1973-01-01

209

SOA FORMATION FROM THE IRRADIATION OF A-PINENE-NOX IN THE ABSENCE AND PRESENCE OF SULFUR DIOXIDE  

EPA Science Inventory

Sulfur dioxide (SO2) is an important constituent in the polluted atmosphere. It is emitted from combustion sources using fuels that contain sulfur. Emissions of SO2 in the United States were reportedly 17 Tg in 1996 with most coming from coal and petroleum combustion. The pr...

210

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

NASA Astrophysics Data System (ADS)

Signatures of sulfur mass-independent fractionation (S-MIF) are observed for sulfur minerals in Archean rocks, and for modern stratospheric sulfate aerosols (SSA) deposited in polar ice. Ultraviolet light photolysis of SO2 is thought to be the most likely source for these S-MIF signatures, although several hypotheses have been proposed for the underlying mechanism(s) of S-MIF production. Laboratory SO2 photolysis experiments are carried out with a flow-through photochemical reactor with a broadband (Xe arc lamp) light source at 0.1 to 5 mbar SO2 in 0.25 to 1 bar N2 bath gas, in order to test the effect of SO2 pressure on the production of S-MIF. Elemental sulfur products yield high ?34S values up to 140 ‰, with ?33S/?34S of 0.59 ± 0.04 and ?36S/?33S ratios of -4.6 ± 1.3 with respect to initial SO2. The magnitude of the isotope effect strongly depends on SO2 partial pressure, with larger fractionations at higher SO2 pressures, but saturates at an SO2 column density of 1018 molecules cm-2. The observed pressure dependence and ?33S/?34S and ?36S/?33S ratios are consistent with model calculations based on synthesized SO2 isotopologue cross sections, suggesting a significant contribution of isotopologue self-shielding to S-MIF for high SO2 pressure (>0.1 mbar) experiments. Results of dual-cell experiments further support this conclusion. The measured isotopic patterns, in particular the ?36S/?33S relationships, closely match those measured for modern SSA from explosive volcanic eruptions. These isotope systematics could be used to trace the chemistry of SSA after large Plinian volcanic eruptions.

Ono, S.; Whitehill, A. R.; Lyons, J. R.

2013-03-01

211

Selective catalytic reduction of sulfur dioxide to elemental sulfur. Final report  

SciTech Connect

This project has investigated new metal oxide catalysts for the single stage selective reduction of SO{sub 2} to elemental sulfur by a reductant, such as CO. Significant progress in catalyst development has been made during the course of the project. We have found that fluorite oxides, CeO{sub 2} and ZrO{sub 2}, and rare earth zirconates such as Gd{sub 2}Zr{sub 2}O{sub 7} are active and stable catalysts for reduction Of SO{sub 2} by CO. More than 95% sulfur yield was achieved at reaction temperatures about 450{degrees}C or higher with the feed gas of stoichiometric composition. Reaction of SO{sub 2} and CO over these catalysts demonstrated a strong correlation of catalytic activity with the catalyst oxygen mobility. Furthermore, the catalytic activity and resistance to H{sub 2}O and CO{sub 2} poisoning of these catalysts were significantly enhanced by adding small amounts of transition metals, such as Co, Ni, Co, etc. The resulting transition metal-fluorite oxide composite catalyst has superior activity and stability, and shows promise in long use for the development of a greatly simplified single-step sulfur recovery process to treat variable and dilute SO{sub 2} concentration gas streams. Among various active composite catalyst systems the Cu-CeO{sub 2} system has been extensively studied. XRD, XPS, and STEM analyses of the used Cu-CeO{sub 2} catalyst found that the fluorite crystal structure of ceria was stable at the present reaction conditions, small amounts of copper was dispersed and stabilized on the ceria matrix, and excess copper oxide particles formed copper sulfide crystals of little contribution to catalytic activity. A working catalyst consisted of partially sulfated cerium oxide surface and partially sulfided copper clusters. The overall reaction kinetics were approximately represented by a first order equation.

Liu, W.; Flytzani-Stephanopoulos, M.; Sarofim, A.F.

1995-06-01

212

Excitation band dependence of sulfur isotope mass-independent fractionation during photochemistry of sulfur dioxide using broadband light sources  

NASA Astrophysics Data System (ADS)

Ultraviolet photolysis of sulfur dioxide (SO2) is hypothesized to be the source of the sulfur isotope mass-independent fractionation (S-MIF) observed in Archean sulfate and sulfide minerals and modern stratospheric sulfate aerosols. A series of photochemical experiments were performed to examine the excitation band dependence of S-MIF during the photochemistry of SO2 under broadband light sources (a xenon arc lamp and a deuterium arc lamp). Optical filters (200 ± 35 nm bandpass and 250 nm longpass filters) were used to separately access two different excitation bands of SO2 in the 190-220 nm and the 250-330 nm absorption regions, respectively. UV irradiation of SO2 in the 190-220 nm and 250-330 nm regions both produced elemental sulfur (S0) and sulfur trioxide (SO3) as end products but yielded very different sulfur isotope signatures. The elemental sulfur products from direct photolysis in the 190-220 nm region were characterized by high ?34S values (154.7-212.0‰), modest ?33S anomalies of 21 ± 3‰, and relatively constant 33? (=ln(?33S + 1)/ln(?34S + 1)) values of 0.64 ± 0.3, all with respect to the initial SO2. Photoexcitation in the 250-330 nm region produced elemental sulfur with ?34S values of 7.7-29.1‰ and ?33S values of 15.0 ± 1.6‰. In both excitation regions, the SO3 products were mass dependently fractionated relative to the SO2 reservoir. The two different absorption regions produced contrasting ?36S/?33S signatures in the elemental sulfur products, with ?36S/?33S = -1.9 ± 0.3 and 0.64 ± 0.3 for the 190-220 nm and 250-330 nm bands, respectively. Our results provide several critical constraints on the origin of the S-MIF signatures observed in modern stratospheric aerosols and in the Archean geological record. A lack of S-MIF in the sulfate product and positive ?36S/?33S ratios for the elemental sulfur from SO2 photo-oxidation demonstrate that photoexcitation in the 250-330 nm region is not a likely source for the S-MIF observed in modern stratospheric aerosols. Large ?34S fractionation, 33? values, and ?36S/?33S ratios observed for the 190-220 nm band are qualitatively consistent with predictions from synthetic isotopologue-specific cross sections. These isotope patterns, however, are not compatible with the Archean rock record. We explore the possibility that S-MIF from both the 190 to 220 nm and the 250 to 330 nm absorption bands could have contributed to the Archean S-MIF signatures.

Whitehill, Andrew R.; Ono, Shuhei

2012-10-01

213

Sulfur dioxide emissions and sectorial contributions to sulfur deposition in Asia  

NASA Astrophysics Data System (ADS)

Anthropogenic and volcanic emissions of SO 2 in Asia for 1987-1988 are estimated on a 1° × 1° grid. Anthropogenic sources are estimated to be 31.6 Tg of SO 2 with the regions' volcanoes emitting an additional 3.8 Tg. For Southeast Asia and the Indian sub-continent, the emissions are further partitioned into biomass, industrial, utilities, and non-specific sources. In these regions emissions from biomass, utilities and industrial sources account for 16.7, 21.7, and 12.2%, respectively. In Bangladesh, ˜ 90% of the SO 2 emissions result from biomass burning and nearly 20% of India's 5 Tg of SO 2 emissions are due to biomass burning. Malaysia and Singapore's emissions are dominated by the utilities with 42 and 62% of their respective emissions coming from that sector. The spatial distribution of sulfur deposition resulting from these emissions is calculated using an atmospheric transport and deposition model. Sulfur deposition in excess of 2 g m -2 yr -1 is predicted in vast regions of east Asia, India, Thailand, Malaysia, Taiwan, and Indonesia with deposition in excess of 5 g m -2 yr -1 predicted in southern China. For the Indian sub-continent and Southeast Asia the contribution of biomass burning, industrial activities, and utilities to total sulfur emissions and deposition patterns are evaluated. Biomass burning is found to be a major source of sulfur deposition throughout southeast Asia. Deposition in Bangladesh and northern India is dominated by this emissions sector. Deposition in Thailand, the Malay Peninsula and the island of Sumatra is heavily influenced by emissions from utilities. The ecological impact of the deposition, in 1988 and in the year 2020, is also estimated using critical loads data developed in the RAINS-ASIA projects. Much of eastern China, the Korean Peninsula, Japan, Thailand, and large regions of India, Nepal, Bangladesh, Taiwan, the Philippines, Malaysia, Indonesia, and sections of Vietnam are at risk due to deposition in excess of their critical loads if emission trends continue at the current rate.

Arndt, Richard L.; Carmichael, Gregory R.; Streets, David G.; Bhatti, Neeloo

214

Adsorption of sulfur dioxide on ammonia-treated activated carbon fibers  

USGS Publications Warehouse

A series of activated carbon fibers (ACFs) and ammonia-treated ACFs prepared from phenolic fiber precursors have been studied to elucidate the role of pore size, pore volume, and pore surface chemistry on adsorption of sulfur dioxide and its catalytic conversion to sulfuric acid. As expected, the incorporation of basic functional groups into the ACFs was shown as an effective method for increasing adsorption of sulfur dioxide. The adsorption capacity for dry SO2 did not follow specific trends; however the adsorption energies calculated from the DR equation were found to increase linearly with nitrogen content for each series of ACFs. Much higher adsorption capacities were achieved for SO2 in the presence of oxygen and water due to its catalytic conversion to H2SO4. The dominant factor for increasing adsorption of SO2 from simulated flue gas for each series of fibers studied was the weight percent of basic nitrogen groups present. In addition, the adsorption energies calculated for dry SO2 were shown to be linearly related to the adsorption capacity of H2SO4 from this flue gas for all fibers. It was shown that optimization of this parameter along with the pore volume results in higher adsorption capacities for removal of SO2 from flue gases. ?? 2001 Elsevier Science Ltd. All rights reserved.

Mangun, C. L.; DeBarr, J. A.; Economy, J.

2001-01-01

215

High-pressure phase equilibrium for the binary systems of {carbon dioxide (1) + dimethyl carbonate (2)} and {carbon dioxide (1) + diethyl carbonate (2)} at temperatures of 273 K, 283 K, and 293 K  

Microsoft Academic Search

Phase equilibrium data for the binary systems {carbon dioxide (CO2)+dimethyl carbonate (DMC)} and {carbon dioxide (CO2)+diethyl carbonate (DEC)} were measured at temperatures of 273K, 283K and 293K in the pressure range of 0.5MPa to 4.0MPa. The measurements were carried out in a cylindrical autoclave with a moveable piston and an observation window. The experimental data were correlated with the Peng–Robison

Chengming Lu; Yiling Tian; Wei Xu; Dan Li; Rongjiao Zhu

2008-01-01

216

EVALUATION OF PROTON-CONDUCTING MEMBRANES FOR USE IN A SULFUR-DIOXIDE DEPOLARIZED ELECTROLYZER  

SciTech Connect

The chemical stability, sulfur dioxide transport, ionic conductivity, and electrolyzer performance have been measured for several commercially available and experimental proton exchange membranes (PEMs) for use in a sulfur dioxide depolarized electrolyzer (SDE). The SDE's function is to produce hydrogen by using the Hybrid Sulfur (HyS) Process, a sulfur based electrochemical/thermochemical hybrid cycle. Membrane stability was evaluated using a screening process where each candidate PEM was heated at 80 C in 60 wt. % H{sub 2}SO{sub 4} for 24 hours. Following acid exposure, chemical stability for each membrane was evaluated by FTIR using the ATR sampling technique. Membrane SO{sub 2} transport was evaluated using a two-chamber permeation cell. SO{sub 2} was introduced into one chamber whereupon SO{sub 2} transported across the membrane into the other chamber and oxidized to H{sub 2}SO{sub 4} at an anode positioned immediately adjacent to the membrane. The resulting current was used to determine the SO{sub 2} flux and SO{sub 2} transport. Additionally, membrane electrode assemblies (MEAs) were prepared from candidate membranes to evaluate ionic conductivity and selectivity (ionic conductivity vs. SO{sub 2} transport) which can serve as a tool for selecting membranes. MEAs were also performance tested in a HyS electrolyzer measuring current density versus a constant cell voltage (1V, 80 C in SO{sub 2} saturated 30 wt% H2SO{sub 4}). Finally, candidate membranes were evaluated considering all measured parameters including SO{sub 2} flux, SO{sub 2} transport, ionic conductivity, HyS electrolyzer performance, and membrane stability. Candidate membranes included both PFSA and non-PFSA polymers and polymer blends of which the non-PFSA polymers, BPVE-6F and PBI, showed the best selectivity.

Hobbs, D.; Elvington, M.; Colon-Mercado, H.

2009-11-11

217

Reactions for improving efficiencies in thermochemical cycles related to the sulfur dioxide-iodine process  

NASA Astrophysics Data System (ADS)

A modification of the sulfur dioxide iodine cycle which uses magnesium oxide, magnesium sulfite and magnesium iodide is examined with particular emphasis on decreasing the amount of water employed and thereby increasing the efficiency. The key reaction is that of iodine with magnesium oxide and magnesium sulfite hexahydrate with no additional water. This produces 77% of the total possible sulfate as well as magnesium iodide, hydrogen iodide and hydrogen at 523 K. The efficiency of this cycle varies between 58% and 39% depending on the amount of heat that can be recovered. This is the first example of a cycle where there is no large energy burden due to evaporation.

Mason, C. F. V.; Bowman, M. G.

1982-06-01

218

Oxaldihydroxamic acid as a new reagent for the fixation of atmospheric sulfur dioxide  

NASA Astrophysics Data System (ADS)

In the present investigation 0.01 M aqueous oxaldihydroxamic acid has been used to stabilize the atmospheric sulfur dioxide. The collection efficiency of the reagent was found to be ~ 100% and the sulfite solution was stable for ? 30 days at room temperature. The sulfite ion was estimated colorimetrically using acidified p-aminoazobenzene and formaldehyde. The pink coloured dye, ?max 505 nm, obeys Beer's law in the range of 0.1-1 ppm. The procedure has been optimized with respect to the acidity, time and reagent concentration. The method is simple, free from pH dependence and several commonly present air pollutants do not interfere.

Paul, Khana Rani; Gupta, V. K.

219

Safety hazards associated with the charging of lithium/sulfur dioxide cells  

NASA Technical Reports Server (NTRS)

A continuing research program to assess the responses of spirally wound, lithium/sulfur dioxide cells to charging as functions of charging current, temperature, and cell condition prior to charging is described. Partially discharged cells that are charged at currents greater than one ampere explode with the time to explosion inversely proportional to the charging current. Cells charged at currents of less than one ampere may fail in one of several modes. The data allows an empirical prediction of when certain cells will fail given a constant charging current.

Frank, H.; Halpert, G.; Lawson, D. D.; Barnes, J. A.; Bis, R. F.

1986-01-01

220

Exhaust-gas imaging via planar laser- induced fluorescence of sulfur dioxide  

NASA Astrophysics Data System (ADS)

The potential use of planar laser-induced fluorescence (PLIF) of sulfur dioxide (SO2) for visualization of exhaust-gas distributions is outlined and demonstrated. Strong absorption features in the UV spectral range allow excitation of SO2 with the fourth harmonic of a Nd:YAG laser at 266 nm. Fluorescence emissions are mostly red-shifted and can be easily detected in single-shot imaging arrangements with a good signal-to-noise ratio. This study uses a premixed methane/air flame that is doped with SO2 to demonstrate the technique. The signal strength has a pronounced temperature dependence for excitation at 266 nm.

Sick, V.

221

Safety hazards associated with the charging of lithium/sulfur dioxide cells  

NASA Astrophysics Data System (ADS)

A continuing research program to assess the responses of spirally wound, lithium/sulfur dioxide cells to charging as functions of charging current, temperature, and cell condition prior to charging is described. Partially discharged cells that are charged at currents greater than one ampere explode with the time to explosion inversely proportional to the charging current. Cells charged at currents of less than one ampere may fail in one of several modes. The data allows an empirical prediction of when certain cells will fail given a constant charging current.

Frank, H.; Halpert, G.; Lawson, D. D.; Barnes, J. A.; Bis, R. F.

1986-09-01

222

Solubilities and heats of solution of sulfur dioxide and hydrogen chloride in disulfur dichloride  

SciTech Connect

Data on the solubilities and solution heats of sulfur dioxide and hydrogen chloride in disulfur dichloride are presented for the purpose of optimizing the removal of these compounds from gases resulting from the production of thionyl chloride. Their removal has been found to contribute to the overall efficiency and productivity of thionyl chloride production and has also made possible their recovery and use as feedstocks in the process. The results of this paper have been tested in the development of a cyclic removal and recovery process which has borne out the theory.

Geiko, V.I.; Gladushko, V.I.; Borovikov, A.Ya.

1987-08-10

223

Magmatic vapor source for sulfur dioxide released during volcanic eruptions: Evidence from Mount Pinatubo  

SciTech Connect

Sulfur dioxide (SO[sub 2]) released by the explosive eruption of Mount Pinatubo of 15 June 1991 had an impact on climate and stratospheric ozone. The total mass of SO[sub 2] released was much greater than the amount dissolved in the magma before the eruption, and thus an additional source for the excess SO[sub 2] is required. Infrared spectroscopic analyses of dissolved water and carbon dioxide in glass inclusions from quartz phenocrysts demonstrate that before eruption the magma contained a separate, SO[sub 2]-bearing vapor phase. Data for gas emissions from other volcanoes in subduction-related arcs suggest that preeruptive magmatic vapor is a major source of the SO[sub 2] that is released during many volcanic eruptions.

Wallace, P.J. (Univ. of Chicago, IL (United States)); Gerlach, T.M. (Geological Survey, Vancouver, WA (United States))

1994-07-22

224

Sulfur dioxide and nitrogen dioxide adsorption on zinc oxide and zirconium hydroxide nanoparticles and the effect on photoluminescence  

NASA Astrophysics Data System (ADS)

Nanoparticulate zinc oxide and micron-size zirconium hydroxide powders have been exposed to sulfur dioxide and nitrogen dioxide by flowing the gases, diluted with nitrogen, over powder samples. X-ray photoelectron spectroscopy (XPS), Raman spectroscopy, and thermogravimetric analysis (TGA) indicate strongly bound, chemisorbed SO3 and NO3 surface species. Two pre-treatments of the nanoparticulate ZnO samples prior to gas exposure have been investigated: (1) drying overnight in a vacuum oven and (2) hydrating the samples by placing them overnight in water-saturated air. A dramatic difference in reactivity of ZnO is observed, with approximately two-fold and ten-fold greater uptake of NO2 and SO2, respectively, measured by XPS for the hydrated samples relative to the dried ones. Transmission electron microscopy (TEM) demonstrates that the greater uptake arises from a morphology change in the case of the hydrated samples. For zirconium hydroxide, no morphology change is observed for hydrated samples, and SO4 (ads), in addition to SO3 (ads), is indicated by XPS. ZnO and Zr(OH)4 both exhibit photoluminescence (PL) spectra, with peak intensities that change dramatically due to hydration and subsequent exposure to SO2 and NO2 gases. Dosing of the powders with these gases effectively reverts the PL spectra to those corresponding to less hydration.

Singh, Jagdeep; Mukherjee, Anupama; Sengupta, Sandip K.; Im, Jisun; Peterson, Gregory W.; Whitten, James E.

2012-05-01

225

Sulfur Dioxide  

MedlinePLUS

... SO 2 : Basic Information - Basics about SO 2 air pollution. Health - Effects of SO 2 air pollution. SO 2 Primary Standards - Links to technical information ... Implementation - Programs and requirements for reducing SO 2 air pollution. Regulatory Actions - Links to proposed and final rules, ...

226

Adsorption of sulfur dioxide by CoFe2O4 spinel ferrite nanoparticles and corresponding changes in magnetism.  

PubMed

Adsorption of sulfur dioxide on 10 nm CoFe(2)O(4) spinel ferrite nanoparticles was examined. Adsorption loadings of sulfur dioxide at breakthrough conditions were determined to be approximately 0.62 mol/kg, which is significant given the 150 m(2)/g surface area of the nanoparticles. Adsorption proceeds through a chemisorption mechanism with sulfur dioxide forming a sulfate upon adsorption on the particle surface, which leads to a 23% decrease in the remnant magnetization, a 20% decrease in the saturation magnetization, and a 9% decrease in the coercivity of the magnetic nanoparticles. Adsorbent materials that provide a magnetic signal when adsorption occurs could have broad implications on adsorption-based separations. PMID:22400990

Glover, T Grant; Sabo, Daniel; Vaughan, Lisa A; Rossin, Joseph A; Zhang, Z John

2012-04-01

227

Ion Clusters in Nucleation Experiments in the CERN Cloud Chamber: Sulfuric Acid + Ammonia + Dimethyl Amine + Oxidized Organics  

NASA Astrophysics Data System (ADS)

Nucleation from gaseous precursors is an important source of aerosol particles in the atmosphere. The CLOUD experiment at CERN provides exceptionally clean and well-defined experimental conditions for studies of atmospheric nucleation and initial growth, in a 26 m3 stainless-steel chamber. In addition, the influence of cosmic rays on nucleation and nanoparticle growth can be simulated by exposing the chamber to a pion beam produced by the CERN Proton Synchrotron. A key to understanding the mechanism by which nucleation proceeds in the CLOUD chamber is the use of state-of-the-art instrumentation, including the Atmospheric Pressure interface Time-Of-Flight (APi-TOF) mass spectrometer. The APi-TOF is developed by Tofwerk AG, and Aerodyne Research, Inc., and typically obtains resolutions between 4000 and 6000 Th/Th and mass accuracies < 10 ppm. Sampling occurs directly from atmospheric pressure through a critical orifice. Ions are then focused and guided to the time-of-flight mass spectrometer, while passing through differentially pumped chambers. No ionization of the sampled aerosol is performed; only ions charged in the chamber are detected in the current configuration. For all studied chemical systems, the APi-TOF detected ion clusters that could directly be linked to nucleation. The composition of these ion clusters could be determined based on their exact masses and isotopic patterns. Aided by the chamber's cleanliness and the possibility of enhancing ion concentrations by using CERN's pion beam, a remarkably large fraction of the ion spectra could be identified, even for more complex chemical systems studied. For the ammonia-sulfuric acid-water system, for instance, growing clusters containing ammonia (NH3) and sulfuric acid (H2SO4) were observed up to 3300 Th. Adding dimethyl amine and/or pinanediol into the CLOUD chamber, altered the chemical compositions of the observed ion clusters accordingly. Cluster growth then included mixtures of sulfuric acid and dimethyl amine and/or a wide range of pinanediol oxidation products. The initial growth of clusters/particles was studied from smallest clusters upwards, using a range of employed instrumentation. Condensation particle counters (such as the Particle Size Magnifier, PSM, by Airmodus Oy), for instance, were specially modified to obtain aerosol number size distributions down to the size of molecular clusters at 1.1 nm (mobility equivalent diameter), and at a time resolution of 2 min. The APi-TOF recorded ion spectra every 5 s; and time series for ion cluster appearance could be usually obtained at a practical time resolution of about 30 s. Therefore, the initial growth of ions could be resolved molecule by molecule, while the largest observable ion clusters corresponded to mobility equivalent diameters of 1.8-2.1 nm. Appearance times and growth rates determined from APi-TOF spectra agreed well with those observed by other instruments such as the PSM.

Worsnop, D. R.; Schobesberger, S.; Bianchi, F.; Ehrhart, S.; Junninen, H.; Kulmala, M. T.

2012-12-01

228

The distribution of sulfur dioxide and other infrared absorbers on the surface of Io  

USGS Publications Warehouse

The Galileo Near Infrared Mapping Spectrometer was used to investigate the distribution and properties of sulfur dioxide over the surface of Io, and qualitative results for the anti-Jove hemisphere are presented here. SO2, existing as a frost, is found almost everywhere, but with spatially variable concentration. The exceptions are volcanic hot spots, where high surface temperatures promote rapid vaporization and can produce SO2-free areas. The pervasive frost, if fully covering the cold surface, has characteristic grain sizes of 30 to 100 Urn, or greater. Regions of greater sulfur dioxide concentrations are found. The equatorial Colchis Regio area exhibits extensive snowfields with large particles (250 to 500 ??m diameter, or greater) beneath smaller particles. A weak feature at 3.15 ??m is observed and is perhaps due to hydroxides, hydrates, or water. A broad absorption in the 1 ??m region, which could be caused by iron-containing minerals, shows a concentration in Io'S southern polar region, with an absence in the Pele plume deposition ring. Copyright 1997 by the American Geophysical Union.

Carlson, R. W.; Smythe, W. D.; Lopes-Gautier, R. M. C.; Davies, A. G.; Kamp, L. W.; Mosher, J. A.; Soderblom, L. A.; Leader, F. E.; Mehlman, R.; Clark, R. N.; Fanale, F. P.

1997-01-01

229

High-resolution photoabsorption cross section measurements of sulfur dioxide between 198 nm and 325 nm  

NASA Astrophysics Data System (ADS)

Accurate photoabsorption cross section data at a range of temperatures are required for the incorporation of sulfur dioxide into atmospheric photochemical models. In addition to its role in the terrestrial atmosphere, sulfur dioxide is observed in significant concentrations in the atmospheres of Venus and Io. Our laboratory measurement program focuses on the very congested SO2 spectrum in the ultraviolet. Using the Imperial College UV Fourier transform spectrometer, we have recorded high-resolution (resolving power (?/??) = 450,000) absorption spectra in the 198 to 325 nm region over a range of temperatures from 160 K to 295 K. This high resolving power allows resolutions approaching those required to fully resolve the Doppler profile of SO2 in the UV. We have reported absolute photoabsorption cross sections at 295 K [Stark et al., JGR Planets 104, 16585 (1999); Rufus et al. JGR Planets 108, doi:10.1029/2002JE001931,(2003)]. Further measurements, at 160 K in the 198 to 200 nm region and at 195 K in the 220 to 325 nm region, have been recorded and analyzed. We present an overview of our new measured cross sections at temperatures and pressures comparable to those found in planetary atmospheres. This work was supported in part by NASA Grant NNG05GA03G, PPARC (UK), and the Leverhulme Trust.

Stark, Glenn; Smith, Peter; Blackie, Douglas; Blackwell-Whitehead, Richard; Pickering, Juliet; Rufus, James; Thorne, Anne

230

Inhalation route effects on exposure to 2. 0 parts per million sulfur dioxide in normal subjects  

SciTech Connect

To investigate possible changes in nasal resistance due to sulfur dioxide (SO{sub 2}) exposure, 14 subjects, healthy non-smokers, between the ages of 20 and 46 years, were exposed for 30 minutes to filtered air while free breathing and to 2.0 ppm SO{sub 2} with either free breathing, forced oral or forced nasal breathing with continuous exercise at a workload 300 kg{center dot}m/min below the workload which initiated cross-over from nasal to oral/nasal breathing in a preliminary incremental workload test. An incremental work test under the ambient conditions was performed immediately following the 30-minute exercise to ascertain any change in the cross-over ventilation. Pre- and post-measures of pulmonary functions were obtained to ascertain any changes in these parameters due to the exposure. There was a significant difference in the workload at which cross-over occurred following forced oral breathing in 2.0 ppm sulfur dioxide. The nasal ventilation prior to cross-over and the nasal component of ventilation were significantly smaller for this exposure condition, indicating a possible change in nasal dynamics following the 30 minutes of forced oral breathing in 2.0 ppm SO{sub 2}. Lack of concomitant changes in pulmonary function tests including airway resistance suggests that breathing 2.0 ppm SO{sub 2} does not affect normal subjects whether administration is by free, forced oral or forced nasal breathing.

Bedi, J.F.; Horvath, S.M. (Univ. of California, Santa Barbara (USA))

1989-11-01

231

NATIONAL PERFORMANCE AUDIT PROGRAM: 1980 PROFICIENCY SURVEY FOR SULFUR DIOXIDE, NITROGEN DIOXIDE, CARBON MONOXIDE, SULFATE, NITRATE, LEAD AND HIGH VOLUME FLOW  

EPA Science Inventory

Based on authority granted by provisions of the Clean Air Act (42 U.S.C 7410, et seq.), the Quality Assurance Division of the Environmental Monitoring Systems Laboratory, Research Triangle Park, NC administers periodic surveys of analytical proficiency for sulfur dioxide, nitroge...

232

FIELD TESTING TO DETERMINE THE PRESENCE OR ABSENCE OF SULFUR DIOXIDE EMISSIONS FROM OLD IN SITU OIL SHALE FIELD-SITES  

EPA Science Inventory

One of the major technology needs in the development of the oil shale industry is to adopt and develop methods for controlling the release of pollutants to the environment. Large quantities of sulfur dioxide may be generated from oil shale retorting operations. Sulfur dioxide is ...

233

[Spatial distribution of sulfur dioxide around a tobacco bulk-curing workshop cluster].  

PubMed

In order to manifest lower energy consumption and less labor employment, and provide the theoretical basis for constructing environmentally friendly modem tobacco agriculture, this paper analyzed gas composition of the chimney from a bulk-curing barn and the dispersion of sulfur dioxide (SO2) around the workshop cluster using ecom-J2KN flue gas analyzer and air sampler. During curing, the concentrations of carbon dioxide (CO2) and SO2 in the chimney were both highest at 38 degrees C, while the concentration of nitrogen oxides (NOx) was highest at 42 degrees C. The emission concentration of SO2 from the chimney was 1327.60-2218.40 mg x m(-3). Average SO2 emission would decrease by 49.7% through adding 4.0% of a sulfur-fixed agent. The highest concentrations of SO2 in the surface soil appeared at the yellowing stage. SO2 concentration in horizontal direction localized at 43-80 m exceeded 0.5 mg x m(-3). The highest concentration of SO2 (0.57 mg x m(-3)) was observed at 50 m. At 50 m in the downstream wind direction of the workshop cluster, SO2 concentration in vertical direction localized at 0.9-1.8 m exceeded 0.5 mg x m(-3), and the highest concentration of SO2 in vertical direction was 0.65 mg x m(-3) at 1.6 m. During curing, the average concentration of SO2 was decreased by 0.43 mg x m(-3) by using the sulfur-fixed agent. The polluted boundary was localized at 120 m in the downstream wind direction of the workshop cluster. PMID:24984508

He, Fan; Wang, Mei; Wang, Tao; Sun, Jian-Feng; Huang, Wu-Xing; Tian, Bin-Qiang; Gong, Chang-Rong

2014-03-01

234

Laboratory measurement of the temperature dependence of gaseous sulfur dioxide (SO 2 ) microwave absorption with application to the Venus atmosphere  

Microsoft Academic Search

High-accuracy laboratory measurements of the temperature dependence of the opacity from gaseous sulfur dioxide (SO2) in a carbon dioxide (CO) atmosphere at temperatures from 290 to 505 K and at pressures from I to 4 atrn have been conducted at frequencies of 2.25 GHz (13.3 cm), 8.5 GHz (3.5 cm), and 21.7 GHz (1.4 cm). Based on these absorptivity measurements,

Shady H. Suleiman; Marc A. Kolodner; Paul G. Steffes

1996-01-01

235

Laboratory measurement of the temperature dependence of gaseous sulfur dioxide (SO2) microwave absorption with application to the Venus atmosphere  

Microsoft Academic Search

High-accuracy laboratory measurements of the temperature dependence of the opacity from gaseous sulfur dioxide (SO2) in a carbon dioxide (CO2) atmosphere at temperatures from 290 to 505 K and at pressures from 1 to 4 atm have been conducted at frequencies of 2.25 GHz (13.3 cm), 8.5 GHz (3.5 cm), and 21.7 GHz (1.4 cm). Based on these absorptivity measurements,

Shady H. Suleiman; Marc A. Kolodner; Paul G. Steffes

1996-01-01

236

Effect of pH on sulfite oxidation by Thiobacillus thiooxidans cells with sulfurous acid or sulfur dioxide as a possible substrate.  

PubMed

The oxidation of sulfite by Thiobacillus thiooxidans was studied at various pH values with changing concentrations of potassium sulfite. The optimal pH for sulfite oxidation by cells was a function of sulfite concentrations, rising with increasing substrate concentrations, while that by the cell extracts was unaffected. The sulfite oxidation by cells was inhibited at high sulfite concentrations, particularly at low pH values. The results from kinetic studies show that the fully protonated form of sulfite, sulfurous acid or sulfur dioxide, is the form which penetrates the cells for the oxidation. PMID:8300544

Takeuchi, T L; Suzuki, I

1994-02-01

237

FLUX DETERMINATION AND PHYSIOLOGICAL RESPONSE IN THE EXPOSURE OF RED SPRUCE TO GASEOUS HYDROGEN PEROXIDE, OZONE, AND SULFUR DIOXIDE  

EPA Science Inventory

We report on the 3-week exposure of a branch of a forest-grown red spruce (Picea rubens) sapling to the combination of gaseous hydrogen peroxide. ozone, and sulfur dioxide. he exposure was conducted continuously using concentrations of H2O2, O3, and SO2 that have been observed du...

238

Sulfur Dioxide-Induced Bronchoconstriction in Asthmatics Exposed for Short Durations under Controlled Conditions: A Selected Review,  

National Technical Information Service (NTIS)

Prior to 1980, essentially no health related effects had been observed for short-term ( < 1 hr) exposures to sulfur dioxide (SO2) levels similar to those found in the ambient environment (= or < 1 ppm). In 1980 and 81, the results from several studies ind...

D. H. Horstman

1987-01-01

239

SULFUR DIOXIDE-INDUCED BRONCHOCONSTRICTION IN ASTHMATICS EXPOSED FOR SHORT DURATIONS UNDER CONTROLLED CONDITIONS: A SELECTED REVIEW  

EPA Science Inventory

Prior to 1980, essentially no health related effects had been observed for short-term ( < 1 hr) exposures to sulfur dioxide (SO2) levels similar to those found in the ambient environment (= or < 1 ppm). In 1980 and 81, the results from several studies indicated that asthmatics' a...

240

Acute and chronic sulfur dioxide fumigation of Pi{tilde n}on pine seeds and seedlings: Data compilation  

SciTech Connect

Pi{tilde n}on pine germinating seeds, emergent seedlings, and one-year-old seedlings were exposed to sulfur dioxide under both acute and chronic exposure conditions. These fumigations were conducted in order to determine the potential for damage to pi{tilde n}on pine in southwestern national parks and monuments where there is potential for exposure to elevated sulfur dioxide concentrations from smelters and power plants. Injury was apparent only in acute fumigations of one-year-old seedlings at ambient sulfur dioxide concentrations of greater than 3 ppm. Chronic fumigations were conducted only a ambient concentrations of 0.2 ppm. Pi{tilde n}on pine resistance was evidenced by lack of effect of fumigation on biomass and growth parameters. Growth rate data for both experimental and control seedlings were fit to a linear growth model with a correlation (r{sup 2} = 0.95). The results of this study agree with other data in the literature and indicate that damage from elevated sulfur dioxide concentrations in southwestern national parks and monuments is much more likely for other, more sensitive, species than for pi{tilde n}on pine.

Trujillo, M.L.; Ferenbaugh, R.W.; Gladney, E.S. [Los Alamos National Lab., NM (United States); Bowker, R.G. [Alma Coll., MI (US). Dept. of Biology

1993-09-01

241

The Social Cost of Trading: Measuring the Increased Damages from Sulfur Dioxide Trading in the United States  

ERIC Educational Resources Information Center

The sulfur dioxide (SO[subscript 2]) cap and trade program established in the 1990 Clean Air Act Amendments is celebrated for reducing abatement costs ($0.7 to $2.1 billion per year) by allowing emissions allowances to be traded. Unfortunately, places with high marginal costs also tend to have high marginal damages. Ton-for-ton trading reduces…

Henry, David D., III; Muller, Nicholas Z.; Mendelsohn, Robert O.

2011-01-01

242

Continuous Crystallization of Sulfur Formed by the Liquid-Phase Reaction of Hydrogen Sulfide and Sulfur Dioxide.  

National Technical Information Service (NTIS)

The crystallization of elemental sulfur is a unit operation in a process being developed to remove hydrogen sulfide from industrial gas streams. The sulfur is formed by the irreversible, liquid-phase reaction of hydrogen sulfide (H(sub 2)S) and sulfur dio...

C. A. Stevens S. Lynn

1989-01-01

243

Effects of ozone and sulfur dioxide mixtures on forest vegetation of the southern Sierra Nevada. Final report  

SciTech Connect

In 1981 and 1982, a multidisciplinary study was conducted within a 32-mile zone from Oildale, CA eastward to points in the southern Sierra Nevada. Concentrations of sulfur in pine needles and lichens along transects tended to decrease with increasing elevation. Stable isotope ratios in soils and plant tissue ran counter to expectations because natural isotopic composition at greater distances is similiar to the source area. Recently germinated pine seedlings exposed to ozone and sulfur dioxide mixtures showed significant differences in root dry weight, suggesting that pollutant mixtures may affect seedling establishment. Surveys of the study area showed increased ozone damage to pines between 1977 and 1981. Sulfur dioxide did not appear to be acting jointly with ozone to cause existing injury.

Taylor, O.C.; Miller, P.R.; Page, A.L.; Lund, L.J.

1986-03-01

244

Thermochemical hydrogen production with the sulfur dioxide-iodine cycle by utilization of dipraseodymium dioxymonosulfate as a recycle reagent  

SciTech Connect

Insoluble, dipraseodymium oxide-sulfite-sulfate-hydrates were prepared by reaction of dipraseodymium dioxymonosulfate with sulfur dioxide in aqueous media at 340/sup 0/K. These compositions reacted with iodine to yield sulfate in the solid phase and hydrogen iodide in the gas phase. High yields of hydrogen iodide were measured at 770/sup 0/K for a reaction time of ten minutes. Yields also depended on the sulfite content of the hydrate compositions, and were highest when the dipraseodymium dioxymonosulfate was 60% neutralized with sulfurous acid. An increased yield of hydrogen iodide was obtained by a second iodine oxidation after separation of the first gaseous products. A water splitting thermochemical cycle utilizing these reactions is described in which hydrogen is produced by catalytic decomposition of hydrogen iodide, and oxygen results from thermal decomposition of the solid product that also yields sulfur dioxide and dipraseodymium dioxymonosulfate for recycle.

Onstott, E.I.; de Bruin, D.

1986-01-01

245

Tree-ring variation in western larch (Larix occidentalis Nutt. ) exposed to sulfur dioxide emissions  

SciTech Connect

Tree-ring analysis of western larch (Larix occidentialis Nutt) demonstrated both direct and indirect affects of sulfur dioxide emissions from the lead/zinc smelter at Trail, B.C. Tree cores were collected from 5 stands known to have been polluted and from 3 control stands. Age effects were removed by fitting theoretical growth curves, and macrocliate was modeled using the average of the controls and two laged values thereof. Separate analyses were performed for years before and after installation of two tall stacks, for drought and nondrought years, and for years prior to initiation of smelting. Regression analyses revealed a negative effect on annual growth that diminished with increasing distance from the smelter and during drought years. Furthermore, chronology statistics suggested an increase in sensitivity to climate that persisted decades beyond implementation of pollution controls, which reduced emissions 10-fold. 38 references, 6 figures, 3 tables.

Fox, C.A.; Kincaid, W.B.; Nash, T.H. III; Young, D.L.; Fritts, H.C.

1984-12-01

246

Sulfur dioxide adsorbed on graphene and heteroatom-doped graphene: a first-principles study  

NASA Astrophysics Data System (ADS)

The adsorption of sulfur dioxide (SO2) on intrinsic graphene and heteroatom-doped (B, N, Al, Si, Cr, Mn, Ag, Au, and Pt) graphene samples was theoretically studied using first-principles approach based on density functional theory to exploit their potential applications as SO2 gas sensors. The structural and electronic properties of the graphene-molecule adsorption adducts are strongly dependent on the dopants. SO2 molecule is adsorbed weakly on intrinsic graphene, and B-, N-doped graphene; in general, strong chemisorption is observed on Al-, Si-, Cr-, Mn-, Ag-, Au-, and Pt-doped graphene. The adsorption mechanisms are discussed from charge transfers and density of states. This work reveals that the sensitivity of graphene-based chemical gas sensors for SO2 can be drastically improved by introducing appropriate dopant, and Cr, as well as Mn, may be the best choices among all the dopants.

Shao, Li; Chen, Guangde; Ye, Honggang; Wu, Yelong; Qiao, Zhijuan; Zhu, Youzhang; Niu, Haibo

2013-02-01

247

Chemical transformations and disproportionation of sulfur dioxide on transition metal complexes  

SciTech Connect

Aside from its renown as a source of acid precipitation, sulfur dioxide is remarkable in possessing physicochemical and coordination properties that are more diverse than those of any other small molecule. SO{sub 2} is amphoteric, behaving as a Lewis acid or base, mild oxidant or reductant, or oxygen donor or acceptor. It is an excellent nonaqueous solvent when liquefied at -10{degrees}C and coordinates to many types of compounds, including metal complexes at both metal and ligand sites, strong Lewis acids, and virtually all nucleophiles, even halide ion. SO{sub 2} can bind strongly to low-valent metals like CO or NO or completely reversibly like O{sub 2} or H{sub 2}. The diversity of metal-SO{sub 2} bonding geometries is unmatched and has been reviewed. This Account will focus on the reactivity of SO{sub 2} e.g. SO double bond cleavage. 72 refs., 7 figs., 1 tab.

Kubas, G.J. [Los Alamos National Lab., NM (United States)

1994-07-01

248

Improving volcanic sulfur dioxide cloud dispersal forecasts by progressive assimilation of satellite observations  

NASA Astrophysics Data System (ADS)

Forecasting the dispersal of volcanic clouds during an eruption is of primary importance, especially for ensuring aviation safety. As volcanic emissions are characterized by rapid variations of emission rate and height, the (generally) high level of uncertainty in the emission parameters represents a critical issue that limits the robustness of volcanic cloud dispersal forecasts. An inverse modeling scheme, combining satellite observations of the volcanic cloud with a regional chemistry-transport model, allows reconstructing this source term at high temporal resolution. We demonstrate here how a progressive assimilation of freshly acquired satellite observations, via such an inverse modeling procedure, allows for delivering robust sulfur dioxide (SO2) cloud dispersal forecasts during the eruption. This approach provides a computationally cheap estimate of the expected location and mass loading of volcanic clouds, including the identification of SO2-rich parts.

Boichu, Marie; Clarisse, Lieven; Khvorostyanov, Dmitry; Clerbaux, Cathy

2014-04-01

249

Evaluation of high Ni-Cr-Mo alloys for the construction of sulfur dioxide scrubber plants  

SciTech Connect

Corrosion in wet lime/limestone systems used for flue gas desulfurization in thermal power plants is of great concern. The frequent variations in acidity and in chloride and fluoride ion concentrations experienced by such systems pose a serious threat to the materials of construction. Currently used materials mostly type 316L stainless steel often fail to meet their life expectancy. The present study evaluates the performance of advanced Ni-Cr-Mo alloys 59 and C-276 in a simulated sulfur dioxide scrubber environment. Accelerated tests showed that high Ni-Cr-Mo alloys have little tendency to leach metal ions such as chromium, nickel, and molybdenum at different impressed potentials. Scanning electron microscopy was used to examine the morphology of pitting attack.

Rajendran, N.; Rajeswari, S. [Univ. of Madras (India). Dept. of Analytical Chemistry

1996-02-01

250

Advanced rechargeable lithium/sulfur dioxide cell. Final report, Sep 88-Feb 91  

SciTech Connect

The electrochemical performance and safety of the rechargeable lithium sulfur dioxide system has been investigated in laboratory cells and in high rate D cells. Small design and active materials were optimized to that cathode utilization of 1.6Ah/gram of carbon and 0.19Ah/cm3 of cathode were achieved with 100-200 cycles. Discharge and charge of cells at temperatures down to -30 C were examined, as were pulse discharge, storage, high temperature, and voltage delay. Analytical techniques were developed for determination of SO2 electrolyte phase behavior and analysis of lithium dithionate degradation product. Cell venting, shorting, and over-heating remain persistent problems as the testing proceeds to the larger spiral-wound cell. Cell venting seems to occur the most on charge, or shortly thereafter, and is associated with accumulation of reactive side-products. Large cell electrodes are pyrophoric when examined in air after extensive cycling.

McDonald, R.C.; Harris, P.; Goebel, F.; Hossain, S.; Vierra, R.

1991-11-01

251

Improvements and Validation of Sulfur Dioxide Retrievals from Aura/OMI Observations of Anthropogenic Pollution  

NASA Astrophysics Data System (ADS)

Both natural and anthropogenic sources can release the trace gas, sulfur dioxide (SO2), into the atmosphere, in which it is usually oxidized to form sulfate aerosols, affecting the environment and climate. The largest contributions to the total annual sulfur budget are anthropogenic emissions from combustions of fossil fuels and smelting of metal ores. While these sources emit SO2 into the atmospheric planetary boundary layer (PBL), leading to air quality degradation near the source regions, the pollutants are sometimes lifted into the free troposphere and subsequently transported over long distances, affecting remote regions. It is therefore important to monitor the spatial and temporal distribution of SO2 over the globe. This can be accomplished with satellite UV remote sensing, as exemplified by the SO2 data derived from the global daily observations made by the Dutch-Finnish Ozone Monitoring Instrument (OMI) on board NASA's Aura spacecraft launched in July 2004. In this presentation, we describe the recent progress in developing an advanced algorithm to improve detection and quantification of anthropogenic SO2, and compare the new retrievals with the operational OMI SO2 products to show significant reduction in noise and bias. We also present validation results obtained by the comparisons with co-located in-situ aircraft measurements in China in 2005 - 2008 and during DISCOVER-AQ field experiment in Maryland in July 2011, to illustrate improved accuracy achieved with the advanced algorithm.

Yang, K.; Krotkov, N. A.; He, H.; Dickerson, R. R.; Li, C.

2011-12-01

252

Sulfur dioxide in the atmosphere of Venus 1 sounding rocket observations  

NASA Technical Reports Server (NTRS)

In this paper we present ultraviolet reflectance spectra obtained during two sounding rocket observations of Venus made during September 1988 and March 1991. We describe the sensitivity of the derived reflectance to instrument calibration and show that significant artifacts can appear in that spectrum as a result of using separate instruments to observe both the planetary radiance and the solar irradiance. We show that sulfur dioxide is the primary spectral absorber in the 190 - 230 nm region and that the range of altitudes probed by these wavelengths is very sensitive to incidence and emission angles. In a following paper Na et. al. (1994) show that sulfur monoxide features are also present in these data. Accurate identification and measurement of additional species require observations in which both the planetary radiance and the solar irradiance are measured with the same instrument. The instrument used for these observations is uniquely suited for obtaining large phase angle coverage and for studying transient atmospheric events on Venus because it can observe targets within 18 deg of the sun while earth orbiting instruments are restricted to solar elongation angles greater than or equal to 45 deg.

Mcclintock, William E.; Barth, Charles A.; Kohnert, Richard A.

1994-01-01

253

Sulfur dioxide in the Venus atmosphere measured by SOIR on board Venus Express  

NASA Astrophysics Data System (ADS)

SO2 is a key constituent of the Venus mesosphere, playing an important role in the atmosphere chemistry, as it is a product of the photodisociation of the clouds constituent, H2SO4. New SO2 observations are important in the frame of constraining Global Computation Models (GCM), which simulate the circulation and the chemistry of the Venus atmosphere. The SOIR instrument flying on board the Venus Express spacecraft records infrared spectra of the Venus atmosphere, using the solar occultation technique. Amongst the species absorbing in the SOIR wavelength range, sulfur dioxide presents a weak band, from which regular observations are obtained in the 60 to 100 km altitude region. We derive number density and volume mixing ratio vertical profiles. Total density and temperature profiles are obtained from the carbon dioxide number density profiles. This study presents the latitude and temporal variations observed between 2006 and 2013. The results are compared to literature data and discussed. Future work will consist of including and comparing the data to Venus GCM.

Mahieux, Arnaud; Carine Vandaele, Ann; Drummond, Rachel; Robert, Séverine; Wilquet, Valérie; Belyaev, Denis; Bertaux, Jean-Loup

2014-05-01

254

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

PubMed

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

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

2014-07-01

255

Sulfur  

Microsoft Academic Search

Sulfur, an element in wide industrial use, currently is mined or recovered in the U.S. from elemental sulfur deposits associated with evaporites, from sulfur-bearing petroleum and natural gas, and from sulfide ores. The element also occurs as a constituent in bedded gypsum and anhydrite, coal, tar sands, and oil shale, as well as in volcanic deposits, none of which is

Bodenlos

1973-01-01

256

Sulfur components analysis in hydrocarbon matrix by gas chromatography. [Methyl mercaptan; ethyl mercaptan; dimethyl sulfide; dimethyl disulfide; methyl ethyl sulfide; diethyl sulfide; diethyl disulfide; dipropyl sulfide  

Microsoft Academic Search

The method described is for analysis of trace levels (0 to 200 ppM) of sulfur compounds. Material used for sample transfer lines, 1 cc gas sample loop and nickel column packed with oxi-propionitrile\\/Porasil C - Durapak 80 to 100 mesh. Two certified standard gas blends were used as calibration gases. Ultrahigh purity helium was used as the carrier gas. An

Puzic

1983-01-01

257

Advances in potentiometric gas sensing: Continuous monitors for ambient ammonia and sulfur dioxide  

SciTech Connect

An introduction to the state of gas monitoring in general, and potentiometric gas sensing in particular, is given. A simply yet new way of collecting analyte gas into a suitable recipient stream is described. Continuously-flowing recipient buffer (pH 7) is exposed directly to the gas sample to be analyzed via a microporous sniffer tube. The collected ammonia converts to ammonium in the buffer and is pumped through an established flow-through ammonium-selective electrode. The optimized sensing arrangement is capable of continuously monitoring sub-ppbv levels of atmospheric ammonia. The paper describes the response time, detection limits, stability, and selectivity characteristics of the new system. The theoretical foundations for the behavior of the sniffer design are discussed, accounting for the observed detection limits and response behavior and predicting the sniffer's response to changes in sample temperature. A new solvent/polymeric electrode membrane based on bis(diethyldithiocarbamato)mercury(II) is introduced. The membrane is highly sensitive to sulfite-ion activity, displaying a lower limit of detection below 1 {mu}M sulfite. It is found to exhibit selectivity towards sulfite over most common ions (iodide, bromide, and reduced-sulfur anions interfere). The selectivity of the potentiometric sensor is enhanced by its incorporation into a flow-through gas sensing arrangement, providing selective determination of sulfite in liquid samples even in the presence of the above interferents. In conjunction with the new sniffer, this membrane can also provide continuous measurement of gas-phase sulfur dioxide at parts-per-billion levels.

Pranitis, D.M.

1988-01-01

258

Catalytic removal of sulfur dioxide from dibenzothiophene sulfone over Mg-Al mixed oxides supported on mesoporous silica.  

PubMed

Dibenzothiophene sulfone (DBTS), one of the products of the oxidative desulfurization of heavy oil, can be removed through extraction as well as by an adsorption process. It is necessary to utilize DBTS in conjunction with catalytic cracking. An object of the present study is to provide an Mg-Al-mesoporous silica catalyst for the removal of sulfur dioxide from DBTS. The characteristics of the Mg-Al-mesoporous silica catalyst were investigated through N2 adsorption, XRD, ICP, and XRF. An Mg-Al-mesoporous silica catalyst formulated in a direct incorporation method showed higher catalytic performance compared to pure MgO during the catalytic removal of sulfur dioxide from DBTS. The higher dispersion of Mg as well as the large surface area of the Mg-Al-mesoporous silica catalyst strongly influenced the catalyst basicity in DBTS cracking. PMID:20359023

You, Nansuk; Kim, Min Ji; Jeong, Kwang-Eun; Jeong, Soon-Yong; Park, Young-Kwon; Jeon, Jong-Ki

2010-05-01

259

Sulfur dioxide and primary carbonaceous aerosol emissions in China and India, 1996-2010  

NASA Astrophysics Data System (ADS)

China and India are the two largest anthropogenic aerosol generating countries in the world. In this study, we develop a new inventory of sulfur dioxide (SO2) and primary carbonaceous aerosol (i.e., black and organic carbon, BC and OC) emissions from these two countries for the period 1996-2010, using a technology-based methodology. Emissions from major anthropogenic sources and open biomass burning are included, and time-dependent trends in activity rates and emission factors are incorporated in the calculation. Year-specific monthly fractions for major sectors and gridded emissions at a resolution of 0.1° × 0.1° distributed by multiple year-by-year spatial proxies are also developed. In China, the interaction between economic development and environmental protection causes large temporal variations in the emission trends. From 1996 to 2000, emissions of all three species showed a decreasing trend (by 9 %-17 %) due to a slowdown in economic growth, a decline in coal use in non-power sectors, and the implementation of air pollution control measures. With the economic boom after 2000, emissions from China changed dramatically. BC and OC emissions increased by 46 % and 33 % to 1.85 Tg and 4.03 Tg in 2010. SO2 emissions first increased by 61 % to 34.0 Tg in 2006, and then decreased by 9.2 % to 30.8 Tg in 2010 due to the wide application of flue-gas desulfurization (FGD) equipment in power plants. Driven by the remarkable energy consumption growth and relatively lax emission controls, emissions from India increased by 70 %, 41 %, and 35 % to 8.81 Tg, 1.02 Tg, and 2.74 Tg in 2010 for SO2, BC, and OC, respectively. Monte Carlo simulations are used to quantify the emission uncertainties. The average 95 % confidence intervals (CIs) of SO2, BC, and OC emissions are estimated to be -16 %-17 %, -43 %-93 %, and -43 %-80 % for China, and -15 %-16 %, -41 %-87 %, and -44 %-92 % for India, respectively. Sulfur content, fuel use, and sulfur retention of hard coal and the actual FGD removal efficiency are the main contributors to the uncertainties of SO2 emissions. Biofuel combustion related parameters (i.e., technology divisions, fuel use, and emission factor determinants) are the largest source of OC uncertainties, whereas BC emissions are also sensitive to the parameters of coal combustion in the residential and industrial sectors and the coke-making process. Comparing our results with satellite observations, we find that the trends of estimated emissions in both China and India are in good agreement with the trends of aerosol optical depth (AOD) and SO2 retrievals obtained from different satellites.

Lu, Z.; Streets, D. G.

2011-07-01

260

Sulfur dioxide and primary carbonaceous aerosol emissions in China and India, 1996-2010  

NASA Astrophysics Data System (ADS)

China and India are the two largest anthropogenic aerosol generating countries in the world. In this study, we develop a new inventory of sulfur dioxide (SO2) and primary carbonaceous aerosol (i.e., black and organic carbon, BC and OC) emissions from these two countries for the period 1996-2010, using a technology-based methodology. Emissions from major anthropogenic sources and open biomass burning are included, and time-dependent trends in activity rates and emission factors are incorporated in the calculation. Year-specific monthly temporal distributions for major sectors and gridded emissions at a resolution of 0.1°×0.1° distributed by multiple year-by-year spatial proxies are also developed. In China, the interaction between economic development and environmental protection causes large temporal variations in the emission trends. From 1996 to 2000, emissions of all three species showed a decreasing trend (by 9 %-17 %) due to a slowdown in economic growth, a decline in coal use in non-power sectors, and the implementation of air pollution control measures. With the economic boom after 2000, emissions from China changed dramatically. BC and OC emissions increased by 46 % and 33 % to 1.85 Tg and 4.03 Tg in 2010. SO2 emissions first increased by 61 % to 34.0 Tg in 2006, and then decreased by 9.2 % to 30.8 Tg in 2010 due to the wide application of flue-gas desulfurization (FGD) equipment in power plants. Driven by the remarkable energy consumption growth and relatively lax emission controls, emissions from India increased by 70 %, 41 %, and 35 % to 8.81 Tg, 1.02 Tg, and 2.74 Tg in 2010 for SO2, BC, and OC, respectively. Monte Carlo simulations are used to quantify the emission uncertainties. The average 95 % confidence intervals (CIs) of SO2, BC, and OC emissions are estimated to be -16 %-17 %, -43 %-93 %, and -43 %-80 % for China, and -15 %-16 %, -41 %-87 %, and -44 %-92 % for India, respectively. Sulfur content, fuel use, and sulfur retention of hard coal and the actual FGD removal efficiency are the main contributors to the uncertainties of SO2 emissions. Biofuel combustion related parameters (i.e., technology divisions, fuel use, and emission factor determinants) are the largest source of OC uncertainties, whereas BC emissions are also sensitive to the parameters of coal combustion in the residential and industrial sectors and the coke-making process. Comparing our results with satellite observations, we find that the trends of estimated emissions in both China and India are in good agreement with the trends of aerosol optical depth (AOD) and SO2 retrievals obtained from different satellites.

Lu, Z.; Zhang, Q.; Streets, D. G.

2011-09-01

261

Evaluation of the first phase of sulfur dioxide and nitrogen oxides provisions of the 1990 Clean Air Act: a plant-based approach.  

PubMed

Electric power generating plants that use coal were among the key targets of Title IV of the 1990 Clean Air Act. Under the first phase of the act, 110 coal-fired electric power plants were required to reduce their sulfur dioxide emissions by 1995 and nitrogen oxide emissions by 1996. Phase 2 of the act requires even greater reduction of sulfur dioxide emissions by 2000 and nitrogen oxide emissions by 2008. This study examines whether the 107 targeted plants (three plants went off-line) have achieved the desired sulfur dioxide and nitrogen oxide emission levels. The analysis of sulfur dioxide is based on data from 1990, 1995, and 1999. The findings show that although sulfur oxide increased by 3% from 1995 to 1999, it decreased by 45% over the 1990-1999 period at the firm level for the targeted firms. The findings also indicate that the overall reduction in sulfur dioxide was achieved by utilizing low sulfur coal and by purchasing emission allowances. So far as nitrogen oxides are concerned, there has been a reduction of 14% over the 1990-1999 period, of which 7% was achieved during the 1995-1999 period. An evaluation of emissions at the plant level indicates that several plants do not meet the emissions level for sulfur dioxide or nitrogen oxides. These results provide a mixed scorecard for reduction in emissions both for sulfur dioxide and nitrogen oxides. Even though there is reduction in the emissions on an overall basis at the firm level, several plants that have not been able to reduce emissions deserve special attention to meet the goals of the act in reducing emissions. PMID:11830772

Freedman, Martin; Jaggi, Bikki

2002-03-01

262

Improvement in the capacity and safety of lithium\\/inorganic electrolyte sulfur dioxide rechargeable cells. Phase 2. Final report, Sep 88-Nov 90  

Microsoft Academic Search

The authors objective was to develop a prototype rechargeable lithium\\/sulfur dioxide\\/carbon cell, using practical AA size hardware, in which the electrolyte was to be a sulfur dioxide solution of lithium bromide or thiocyanate, together with a highly soluble cosolute, a second non-lithium salt of the same anion. The cosolute was intended to replace the organic cosolvents familiar from the primary

C. R. Schlaikjer; M. D. Jones; A. P. Johnson; J. E. Torkelson; W. VanSchalkwijk

1990-01-01

263

Formation of secondary organic aerosol from irradiated ?-pinene\\/toluene\\/NOx mixtures and the effect of isoprene and sulfur dioxide  

Microsoft Academic Search

Secondary organic aerosol (SOA) was generated by irradiating a series of ?-pinene\\/toluene\\/NOx mixtures in the absence and presence of isoprene or sulfur dioxide. The purpose of the experiment was to evaluate the extent to which chemical perturbations to this base-case (?-pinene\\/toluene) mixture led to changes in the gas-phase chemistry which strongly influences mass and composition of SOA and secondary organic

Mohammed Jaoui; Edward O. Edney; Tadeusz E. Kleindienst; Michael Lewandowski; John H. Offenberg; Jason D. Surratt; John H. Seinfeld

2008-01-01

264

Prediction of ground level concentration of sulfur dioxide using ISCST3 model in Mangalore industrial region of India  

Microsoft Academic Search

Ambient air quality management in any industrial area is of prime concern in India considering the industrial growth since\\u000a last two decades. High concentrations of ambient sulfur dioxide (SO2) in many Indian places are responsible for non-compliance of ambient air quality standards. Dispersion modeling finds an\\u000a important tool to simulate the ambient air quality of a region and to predict

Amitava Bandyopadhyay

2009-01-01

265

A Comparison of Sulfur Dioxide Column Content Between Aircraft and Satellite Over the U.S. Mid-Atlantic  

Microsoft Academic Search

Sulfur Dioxide (SO2) is a major contributor to air pollution in the mid-Atlantic region of the United States. Sources of SO2 include coal fired power plants as well as diesel engines. Fine particulate sulfate (with diameter less than 2.5 mm) formed from SO2 can cause health problems as well as decreased visibility. Reliable measurements of SO2 within the lower troposphere

J. C. Hains; R. R. Dickerson; B. G. Doddridge; J. P. Burrows; A. Richter

2002-01-01

266

Comparative effects of sulfur dioxide exposures at 5 degrees C and 22 degrees C in exercising asthmatics  

Microsoft Academic Search

Either airway cooling or sulfur dioxide (SOâ) can induce bronchoconstriction in many asthmatics. Whether these two stresses act synergistically is a question with important public health implications. Eight young adult asthmatic volunteers were exposed to SOâ at 0.0, 0.2, 0.4, and 0.6 ppm, during 5 min heavy exercise at 5 degrees C, both with high (approximately 85%) and with low

W. S. Linn; D. A. Shamoo; T. G. Venet; R. M. Bailey; L. H. Wightman; J. D. Hackney

1984-01-01

267

Effects of Sulfur Dioxide Fumigation in Open-Top Field Chambers on Soil Acidification and Exchangeable Aluminum1  

Microsoft Academic Search

The effects of sulfur dioxide (SO2) fumigation in open-top field chambers on soil pH and exchangeable AI were evaluated. Soil sam- ples were taken from the surface 0-8 cm in plots where tomato (Lycopersicum esculentum L. 'Jet Star') plants were grown. Treat- ments were: 0, 0.06, 0.12, 0.24, and 0.48 ppm SO2 in non-filtered (NF) air, and 0, 0.12, and

Edward H. Lee; Howard E. Heggestad; Jesse H. Bennett

1982-01-01

268

Effects of sulfur dioxide fumigation in open-top field chambers on soil acidification and exchangeable aluminum  

Microsoft Academic Search

The effects of sulfur dioxide (SOâ) fumigation in open-top field chambers on soil pH exchangeable Al were evaluated. Soil samples were taken from the surface 0-8 cm in plots where tomato (Lycopersicum esculentum L. 'Jet Star') plants were grown. Treatments were: 0, 0.06, 0.12, 0.24, and 0.48 ppm SOâ in non-filtered (NF) air, and 0, 0.12, and 0.48 ppm SOâ

E. H. Lee; H. E. Heggestad; J. H. Bennett

2009-01-01

269

Effects of controlled levels of sulfur dioxide on the nutrient quality of western wheatgrass and prairie June grass  

SciTech Connect

Effects of low level (0, 2, 5, and 10 pphm) sulfur dioxide (SO/sub 2/) fumigation on nutrient quality of western wheatgrass and prairie June grass were investigated. Analyses indicated significantly higher levels of sulfur on fumigated vs. control plots. Accumulation rates of sulfur in tissues were greatest in the high treatment (0.0022%/day) followed by the medium (0.0015%/day) and low (0.0002%/day) treatments. Concentrations of sulfur in control plants did not change with time. Ash concentrations paralleled sulfur concentrations and major increases in ash content of plant tissue were attributed to the increased levels of sulfur. Crude protein levels varied seaonally, regardless of fumigation level, with the highest concentrations in May and the lowest in August. There were significantly lower levels of crude protein on treatment plots fumigated for 2 years compared to controls. This significant reduction was attributed to SO/sub 2/ fumigation. Cell-wall constituent analysis indicated SO/sub 2/ fumigation did not measurably alter the fiber content of plant tissue. Digestion of dry matter was significantly higher on treatments fumigated for one year than those fumigated for two years. In general, digestion of dry matter paralleled crude protein concentrations. 24 references, 4 figures, 5 tables.

Schwartz, C.C.; Lauenroth, W.K.; Heitschmidt, R.K.

1984-01-01

270

Relationship between ambient sulfur dioxide levels and neonatal mortality near the Mt. Sakurajima volcano in Japan.  

PubMed

We examined the association between neonatal mortality and ambient sulfur dioxide (SO2) levels in the neighborhood of Mt. Sakurajima, Yamashita public health district of Kagoshima City, during the period between 1978 and 1988. The analysis using Poisson regression models showed that the monthly average level of SO2 was positively associated with the neonatal mortality (P = 0.002). When the SO2 levels were categorized into four groups to estimate the relative risk (RR) of neonatal mortality using the lowest exposure category as a reference, the RR increased with elevated exposure levels (P for trend < 0.001) and was the highest in the group with the highest level of exposure (RR = 2.2, 95% confidence interval; 1.2-4.1). Other than SO2, we also examined the number of eruptions, the amount of ashfall, and the average level of suspended particulate matter. None of these factors was associated with neonatal mortality. Although the present study suggests that increase in SO2 levels has had an adverse effect on neonatal mortality in the neighborhood of Mt. Sakurajima, it is difficult to determine the source of the SO2. Further studies are necessary to elucidate the mechanisms of the excess neonatal mortality probably associated with the volcanic SO2 levels. PMID:10616268

Shinkura, R; Fujiyama, C; Akiba, S

1999-11-01

271

Estimating the altitude of volcanic sulfur dioxide plumes from space borne hyper-spectral UV measurements  

NASA Astrophysics Data System (ADS)

The altitude of volcanic sulfur dioxide (SO2) plumes determines the transport and atmospheric residence time of derived sulfate aerosol, and hence their impacts on the environment and climate. Knowledge of the altitude of fresh eruption clouds is also very important in aviation safety to avoid flying through ash clouds and for forecasting of plume drift. In this paper, we demonstrate the altitude dependence of the spectral response in the backscattered ultraviolet (BUV) radiance when a SO2 absorption layer is added to an ozone-laden atmosphere. The distinctive spectral response serves as the physical basis for simultaneous SO2 loading and altitude retrievals, which can improve the characterization of volcanic emissions. We accomplish this by extending the recently developed Iterative Spectral Fitting (ISF) algorithm to include effective plume altitude determination when performing simultaneous ozone and SO2 retrievals. The extended ISF algorithm is applied to hyper-spectral Ozone Monitoring Instrument (OMI) measurements of two volcanic eruptions: Sierra Negra in October 2005 and Jebel al Tair in September 2007. The results show for the first time that a wide range of SO2 plume altitudes can be estimated directly from hyper-spectral BUV radiance measurements.

Yang, Kai; Liu, Xiong; Krotkov, Nickolay A.; Krueger, Arlin J.; Carn, Simon A.

2009-05-01

272

Removal of sulfur dioxide from flue gas using the sludge sodium humate.  

PubMed

This study shows the ability of sodium humate from alkaline treatment sludge on removing sulfur dioxide (SO2) in the simulated flue gas. Experiments were conducted to examine the effect of various operating parameters, like the inlet SO2 concentration or temperature or O2, on the SO2 absorption efficiency and desulfurization time in a lab-scale bubbling reactor. The sludge sodium humate in the supernatant after alkaline sludge treatment shows great performance in SO2 absorption, and such efficiency can be maintained above 98% with 100 mL of this absorption solution at 298 K (flue gas rate of 0.12 m(3)/h). The highest SO2 absorption by 1.63 g SHA-Na is 0.946 mmol in the process, which is translated to 0.037 g SO2 g(-1) SHA-Na. The experimental results indicate that the inlet SO2 concentration slightly influences the SO2 absorption efficiency and significantly influences the desulfurization time. The pH of the absorption solution should be above 3.5 in this process in order to make an effective desulfurization. The products of this process were characterized by Fourier transform infrared spectroscopy and X-ray diffraction. It can be seen that the desulfurization products mainly contain sludge humic acid sediment, which can be used as fertilizer components. PMID:24453875

Zhao, Yu; Hu, Guoxin

2013-01-01

273

Reduction of sulfur dioxide over alumina-supported molybdenum sulfide catalysts  

SciTech Connect

This paper on an experimental investigation of the reduction of SO{sub 2} with CH{sub 4} using molybdenum sulfide supported on alumina as a catalyst that was carried out. Three molybdenum loadings of 5, 10, and 15% were used. In addition, a catalyst which contained cobalt (5% Co-15% Mo/Al{sub 2}O{sub 3}) was evaluated. The evaluations were based on the activity as well as the yields of sulfur and carbon dioxide. Experiments were carried out at temperatures ranging from 650 to 725{degrees}C and inlet molar feed ratios of SO{sub 2} to CH{sub 4} of 1.0 and 2.0. The 5 and 10% molybdenum loadings showed similar activities and yields to each other. The catalyst containing 15% molybdenum had the highest activity and yields. All catalysts tested were more effective than alumina itself. THe activity of the 15% Mo/Al{sub 2}O{sub 3} catalyst was 1.5-2 times that of alumina. This catalyst was stable under all reaction conditions. The addition of cobalt reduced the activity by 20%. In order to minimize the production of undesired by-products, the reaction temperature should be less than 700{degrees}C.

Mulligan, D.J.; Berk, D. (Dept. of Chemical Engineering, McGill Univ., Montreal, Quebec H3A 2A7 (CA))

1992-01-01

274

A model for the oxidation of sulfur dioxide in a trickle-bed reactor  

SciTech Connect

A reaction rate model based on complete wetting of the catalyst particles in a trickle-bed reactor is presented. It is considered that the pendular rings are formed at the contact points of the particles and the liquid flows down as thin films on the remaining surface between the pendular rings. Assuming that the flow in the films is laminar, the liquid in the pendular rings is well-mixed, and a fraction of the liquid flowing in the films bypasses the pendular rings, the reaction rate was found. The data obtained for oxidation of sulfur dioxide on activated carbon were used to test the model predictions of the dependence of reaction rate on liquid velocity. The reaction rates in nonprewetted beds were found to be lower than those in prewetted beds. The proposed model correlated the observed reaction rates satisfactorily, with the fractional thickness of the film that bypasses the pendular ring as an adjustable parameter. The model also predicted the reaction rate trends, including the minimum of the oxidation rate reported by Mata and Smith.

Ravindra, P.V.; Rao, D.P.; Rao, M.S. [Indian Inst. of Tech., Kanpur (India). Dept. of Chemical Engineering] [Indian Inst. of Tech., Kanpur (India). Dept. of Chemical Engineering

1997-12-01

275

Sulfur dioxide relaxes rat aorta by endothelium-dependent and -independent mechanisms.  

PubMed

This study aimed to investigate the vasoactivity of sulfur dioxide (SO2), a novel gas identified from vascular tissue, in rat thoracic aorta. The thoracic aorta was isolated, cut into rings, and mounted in organ-bath chambers. After equilibrium, the rings were gradually stretched to a resting tension. Isometric tension was recorded under the treatments with vasoconstrictors, SO2 derivatives, and various drugs as pharmacological interventions. In endothelium-intact aortic rings constricted by 1 microM phenylephrine (PE), SO2 derivatives (0.5-8 mM) caused a dose-dependent relaxation. Endothelium removal and a NOS inhibitor L-NAME reduced the relaxation to low doses of SO2 derivatives, but not that to relatively high doses (>or=2 mM). In endothelium-denuded rings, SO2 derivatives attenuated vasoconstriction induced by high K+ (60 mM) or CaCl2 (0.01-10 mM). The relaxation to SO2 derivatives in PE-constricted rings without endothelium was significantly inhibited by blockers of ATP-sensitive K+(KATP) and Ca2+-activated K+ (KCa) channels, but not by those of voltage-dependent K+ channels, Na+- K+-ATPase or Na+-Ca2+ exchanger. SO2 relaxed vessel tone via endothelium-dependent mechanisms associated with NOS activation, and via endothelium-independent mechanisms dependent on the inhibition of voltage-gated Ca2+ channels, and the opening of KATP and KCa channels. PMID:18657003

Wang, Y-K; Ren, A-J; Yang, X-Q; Wang, L-G; Rong, W-F; Tang, C-S; Yuan, W-J; Lin, L

2009-01-01

276

Removal of hydrogen sulfide and sulfur dioxide by carbons impregnated with triethylenediamine.  

PubMed

Activated carbon (AC) adsorption has long been considered to be a readily available technology for providing protection against exposure to acutely toxic gases. However, ACs without chemical impregnation have proven to be much less efficient than impregnated ACs in terms of gas removal. The impregnated ACs in current use are usually modified with metalloid impregnation agents (ASC-carbons; copper, chromium, or silver) to simultaneously enhance the chemical and physical properties of the ACs in removing specific poisonous gases. These metalloid agents, however, can cause acute poisoning to both humans and the environment, thereby necessitating the search for organic impregnation agents that present a much lower risk. The aim of the study reported here was to assess AC or ASC-carbon impregnated with triethylenediamine (TEDA) in terms of its adsorption capability for simulated hydrogen sulfide (H2S) and sulfur dioxide (SO2) gases. The investigation was undergone in a properly designed laboratory-scale and industrial fume hood evaluation. Using the system reported here, we obtained a significant adsorption: the removal capability for H2S and SO2 was 375 and 229 mg/g-C, respectively. BET measurements, element analysis, scanning electron microscopy, and energy dispersive spectrometry identified the removal mechanism for TEDA-impregnated AC to be both chemical and physical adsorption. Chemical adsorption and oxidation were the primary means by which TEDA-impregnated ASC-carbons removed the simulated gases. PMID:18200931

Wu, Li-Chun; Chang, Tsu-Hua; Chung, Ying-Chien

2007-12-01

277

Exploring the Capabilities of Satellite Observation of Anthropogenic Sulfur Dioxide (SO2) in the Lower Atmosphere  

NASA Astrophysics Data System (ADS)

Anthropogenic activities, such as fuel combustion, oil refining, and metal smelting, emit sulfur dioxide (SO2) into the atmospheric planetary boundary layer (PBL), leading to air quality degradation near the source regions. SO2 in the air is oxidized to form sulfate aerosols, which may have a significant impact on regional air quality and climate. Sulfate aerosols are usually removed from the atmosphere through acid deposition, which can damage the environment and ecosystems. SO2 and sulfate aerosols are sometimes lifted into the middle or upper troposphere and subsequently transported over long distances, affecting remote regions. Space-borne UV instruments, such as Aura/OMI, MetOp/GOME-2, and NPP/OMPS, provide a unique perspective on the spatial and temporal distribution of SO2 over the globe. In this presentation, we will describe the recent advances in retrieval algorithm that provide improved detection and quantification of PBL SO2, and compare the new retrievals with the operational OMI SO2 products to show significant reduction in noise and bias. We will also present validation results obtained by the comparisons with co-located in-situ aircraft measurements to illustrate improved accuracy achieved with the advanced algorithm.

Yang, K.; Krotkov, N. A.; Li, C.; He, H.; Dickerson, R. R.

2012-12-01

278

Removal of Sulfur Dioxide from Flue Gas Using the Sludge Sodium Humate  

PubMed Central

This study shows the ability of sodium humate from alkaline treatment sludge on removing sulfur dioxide (SO2) in the simulated flue gas. Experiments were conducted to examine the effect of various operating parameters, like the inlet SO2 concentration or temperature or O2, on the SO2 absorption efficiency and desulfurization time in a lab-scale bubbling reactor. The sludge sodium humate in the supernatant after alkaline sludge treatment shows great performance in SO2 absorption, and such efficiency can be maintained above 98% with 100?mL of this absorption solution at 298?K (flue gas rate of 0.12?m3/h). The highest SO2 absorption by 1.63?g SHA-Na is 0.946?mmol in the process, which is translated to 0.037?g SO2 g?1 SHA-Na. The experimental results indicate that the inlet SO2 concentration slightly influences the SO2 absorption efficiency and significantly influences the desulfurization time. The pH of the absorption solution should be above 3.5 in this process in order to make an effective desulfurization. The products of this process were characterized by Fourier transform infrared spectroscopy and X-ray diffraction. It can be seen that the desulfurization products mainly contain sludge humic acid sediment, which can be used as fertilizer components.

Hu, Guoxin

2013-01-01

279

Sulfur Dioxide Emission Rates of Kilauea Volcano, Hawaii, 1979-1997  

USGS Publications Warehouse

INTRODUCTION Sulfur dioxide (SO2) emission rates from Kilauea Volcano were first measured by Stoiber and Malone (1975) and have been measured on a regular basis since 1979 (Casadevall and others, 1987; Greenland and others, 1985; Elias and others, 1993; Elias and Sutton, 1996). The purpose of this report is to present a compilation of Kilauea SO2 emission rate data from 1979 through 1997 with ancillary meteorological data (wind speed and wind direction). We have included measurements previously reported by Casadevall and others (1987) for completeness and to improve the usefulness of this current database compilation. Kilauea releases SO2 gas predominantly from its summit caldera and rift zones (fig. 1). From 1979 through 1982, vehicle-based COSPEC measurements made within the summit caldera were adequate to quantify most of the SO2 emitted from the volcano. Beginning in 1983, the focus of SO2 release shifted from the summit to the east rift zone (ERZ) eruption site at Pu`u `O`o and, later, Kupaianaha. Since 1984, the Kilauea gas measurement effort has been augmented with intermittent airborne and tripod-based surveys made near the ERZ eruption site. In addition, beginning in 1992 vehicle-based measurements have been made along a section of Chain of Craters Road approximately 9 km downwind of the eruption site. These several types of COSPEC measurements continue to the present.

Elias, Tamar; Sutton, A. J.; Stokes, J. B.; Casadevall, T. J.

1998-01-01

280

Sulfur Dioxide Emission Rates from Kilauea Volcano, Hawai`i, an Update: 1998-2001  

USGS Publications Warehouse

Introduction Sulfur dioxide (SO2) emission rates from Kilauea Volcano were first measured by Stoiber and Malone (1975) and have been measured on a regular basis since 1979 (Greenland and others, 1985; Casadevall and others, 1987; Elias and others, 1998; Sutton and others, 2001). A compilation of SO2 emission-rate and wind-vector data from 1979 through 1997 is available as Open-File Report 98-462 (Elias and others, 1998) and on the web at http://hvo.wr.usgs.gov/products/OF98462/. The purpose of this report is to update the existing database through 2001. Kilauea releases SO2 gas predominantly from its summit caldera and east rift zone (ERZ) (fig. 1), as described in previous reports (Elias and others, 1998; Sutton and others, 2001). These two distinct sources are quantified independently. The summit and east rift zone emission rates reported here were derived using vehicle-based Correlation Spectrometry (COSPEC) measurements as described in Elias and others (1998). In 1998 and 1999, these measurements were augmented with airborne and tripod-based surveys.

Elias, Tamar; Sutton, A. Jefferson

2002-01-01

281

Sulfur Dioxide Emission Rates from Kilauea Volcano, Hawai`i, an Update: 2002-2006  

USGS Publications Warehouse

Introduction Sulfur dioxide (SO2) emission rates from Kilauea Volcano were first measured by Stoiber and Malone (1975) and have been measured on a regular basis since 1979 (Greenland and others, 1985; Casadevall and others, 1987; Elias and others, 1998; Sutton and others, 2001, Elias and Sutton, 2002, Sutton and others, 2003). Compilations of SO2 emission-rate and wind-vector data from 1979 through 2001 are available on the web. (Elias and others, 1998 and 2002). This report updates the database through 2006, and documents the changes in data collection and processing that have occurred during the interval 2002-2006. During the period covered by this report, Kilauea continued to release SO2 gas predominantly from its summit caldera and east rift zone (ERZ) (Elias and others, 1998; Sutton and others, 2001, Elias and others, 2002, Sutton and others, 2003). These two distinct sources are always measured independently (fig.1). Sulphur Banks is a minor source of SO2 and does not contribute significantly to the total emissions for Kilauea (Stoiber and Malone, 1975). From 1979 until 2003, summit and east rift zone emission rates were derived using vehicle- and tripod- based Correlation Spectrometry (COSPEC) measurements. In late 2003, we began to augment traditional COSPEC measurements with data from one of the new generation of miniature spectrometer systems, the FLYSPEC (Horton and others, 2006; Elias and others, 2006, Williams-Jones and others, 2006).

Elias, Tamar; Sutton, A. J.

2007-01-01

282

Sulfur dioxide emissions during the 2011 eruption of Shinmoedake volcano, Japan  

NASA Astrophysics Data System (ADS)

Sulfur dioxide flux of the 2011 Shinmoedake eruption, which started in January 2011, was measured repeatedly throughout its activity. The SO2 flux, which was greater than 10,000 ton/day during the earlier stages, quickly decreased to below 1,000 ton/day over the following two weeks. The flux decreased gradually thereafter to about 200 ton/day by the second half of March 2011. It continued at that level until April 2012. To evaluate the amount of SO2 emitted during the 2011 eruption, daily SO2 flux was estimated based on direct observations and other information. The total SO2 emissions were about 280 kt, with nearly two-thirds emitted during the first two weeks. The degrees of excess degassing estimated for the lava accumulation stages were low (2.3-2.9), suggesting a small pre-eruptive bubble content in the magma. High SO2 flux observed immediately after the sub-Plinian eruptions and before rapid lava effusion is probably related to the extensive degassing of magma in the conduit, which probably played a role in the transition from explosive to effusive eruption. An abrupt and large flux decrease occurred around February 8, 2011, which might be attributable to depletion of pre-eruptive bubbles in the magma.

Mori, T.; Kato, K.

2013-06-01

283

Ion chromatographic measurement of fluoride and sulfur dioxide in samples collected at aluminum smelters  

SciTech Connect

Measurement of airborne fluoride and sulfur dioxide in aluminum smelting plants is important for both industrial hygiene and environmental reasons. The traditional analytical techniques employed have been ion-selective electrodes (ISE) for fluoride and barium/thorin titration for SO2. In this study, ion chromatography (IC) was evaluated as a substitute for these two techniques. Dust for particulate fluoride was collected on membrane filters with carbonate-treated backup pads to collect HF and SO2. Gaseous fluoride and SO2 were ultrasonically extracted from the treated pad, but particulate fluoride required a borate/carbonate fusion. Collection efficiency and recovery of the analytes, along with the acceptable working ranges and instrument conditions used with IC, are discussed. IC is a desirable substitute for the electrode and titration methods because it is easily automated and the two determinations may be performed simultaneously. Organic compounds may cause interference in low-level fluoride measurement. Comparison of the techniques for field samples indicates that IC is an adequate substitute for the traditional measurement methods for full-shift samples of fluoride.

Balya, D.R. (Aluminum Company of America, Alcoa Technical Center, PA (United States))

1991-08-01

284

Sulfur dioxide restores calcium homeostasis disturbance in rat with isoproterenol-induced myocardial injury.  

PubMed

Backgrounds: sulfur dioxide (SO?) could relieve isoproterenol (ISO)-induced myocardial injury, while the mechanism is unclear. This study aims to explore whether the protective effect of SO? on ISO-induced myocardial injury was mediated by the restoration of calcium homeostasis disturbance in cardiomyocyte. Methods and results: Rats were randomly divided into four groups: ISO group, ISO+SO? group, control group and SO? group. Content of Ca²? in H9c2 cells was assayed using confocal microscope, and cardiac function parameters were measured by echocardiography. Plasma biochemical values and myocardial ultra-structure changes were measured. Meanwhile, the activity, protein and gene levels of sarcoplasmic reticulum Ca²? ATPase (SERCA), and protein and phosphorylation of phospholamban (PLN) were detected. We found SO? derivatives could restore the decreased cardiac function, the abnormal lactate dehydrogenase, creatine kinase, alpha-hydroxybutyrate dehydrogenase, potassium, calcium, blood urea nitrogen and the damaged myocardial ultra-structure in rats, and regulate the increased Ca²? content in H9c2 induced by ISO. In addition, compared with ISO group, the decreased activities, protein and mRNA level of SERCA, as well as the decreased protein phosphorylation level of PLN in myocardial tissues were increased in ISO+SO? group. Conclusion: SO? derivatives might relieve calcium overload in association with the upregulating expression of SERCA and p-PLN/PLN by myocardial tissues in rats with ISO-induced myocardial injury. PMID:22806909

Chen, Shanshan; Du, Junbao; Liang, Yinfang; Zhang, Rongyuan; Tang, Chaoshu; Jin, Hongfang

2012-09-01

285

Selective absorption of hydrogen chloride from flue gases in the presence of sulfur dioxide  

SciTech Connect

Detailed results of static and dynamic experiments to determine the vapor-liquid equilibrium for HCl and the co-absorption of hydrogen chloride and sulfur dioxide in concentrated solutions of calcium chloride are presented. The mathematical treatment of the data derived from the experiments demonstrates that, with an acid concentration in the region of 0.01% in 30% CaCl/sub 2/ solution, the concentration of HCl in the gas phase could be maintained below 1 ppm. The dynamic data show that over a pH range 1.5 - 2.0 the absorption efficiency for HCl is greater than 95% whilst SO/sub 2/ is not absorbed. Over the pH range 1.8 - 2.0 the absorption of HCl is essentially 100%. Although a number of questions still remains to be answered before any industrial application could be defined, a conceptual process flowsheet has been developed which shows how the process is seen to fit between the booster blower and absorber of the typical Wellman-Lord flowsheet. Further development work on the laboratory and pilot-plant is necessary. 4 references, 7 figures.

Kyte, W.S.; Bettelheim, J.; Nicholson, N.E.; Scarlett, J.

1984-08-01

286

Removal of sulfur dioxide and\\/or trioxide from gaseous effluents of fossil fuel operated power and steam plants. [weak acid, cation exchange resins  

Microsoft Academic Search

The removal of sulfur dioxide (SOâ) and\\/or sulfur trioxide (SOâ) from the gaseous effluents of fossil fuel burning steam and power plants using certain macroreticular, weak acid, cation exchange resins is described. The gaseous streams to be treated may be derived from other sources but the invention has particular utility and applicability in the control of pollution emanating from the

Kunin

1975-01-01

287

Sulfur dioxide in the Wollongong\\/Port Kembla area: a historical review of ambient atmospheric levels, major emission sources and their regulation  

Microsoft Academic Search

Air pollution from sulfur dioxide (SO2) in the Wollongong\\/Port Kembla region, New South Wales, Australia, has been of major concern for nearly 100 years. This longterm situation is due to the presence of local major industries which emit the gas, in particular, a copper smelter at Port Kembla, established in 1907. Extensive information on the emission and control of sulfur

Peter Bloem

2007-01-01

288

[Effects of volcanic sulfur dioxide on reconstruction workers and residents returning to Miyake Island].  

PubMed

Four and half years have passed since Mt. Oyama in Miyake Island erupted. Ambient sulfur dioxide (SO2) is still above the environmental air standard in parts of the island, even though emission of the volcanic gas has diminished. Reconstruction of life-support infrastructure in the island and safety measures started in July 2002, and a short-term trial stay project for former residents was completed in April 2003 for the total rehabilitation of the island. We conducted health examinations, and questionnaires on clinical symptoms among the reconstruction workers in January 2003, as well as questionnaires on respiratory symptoms among former residents who joined the trial stay, in late fall of 2003. The peak expiratory flow rate and symptoms of the workers and the symptoms of the short-term residents were not correlated to SO2 concentrations. In addition, we investigated the medical histories of outpatients at Miyake-mura National Insurance Center Clinic. We could not recognize any cases directly connected with higher ambient SO2 concentration in the area of the island, but there was a male worker, in his thirties, who suffered an initial attack of bronchial asthma, which required intensive care and treatment. As a general rule, all the workers and the residents are asked to wear gas masks for SO2 when its concentration is above 2.0 ppm and to stay in the house with desulfuration facilities as a precautionary measure at night. The residents are now well informed about the risks of volcanic gas and preventive measures for adverse health effects. We could not evaluate correlations between SO2 exposure indices and health effects sufficiently due to the limitation of the field study, but this study presents useful pieces of information as a risk communication for reconstruction workers and former inhabitants to the island. PMID:16130894

Uno, Hideyuki; Horiguchi, Hyogo; Omae, Kazuyuki; Uchiyama, Iwao; Kudo, Shoji; Kayama, Fujio

2005-07-01

289

Trends and effectiveness of emission control of sulfur dioxide in China: a satellite perspective  

NASA Astrophysics Data System (ADS)

The combination of two satellite instruments (OMI and SCIAMACHY) provides high quality space-borne measurements for the trend analysis of sulfur dioxide (SO2) column density. An improved product of SO2 retrievals from these two satellites was derived with the consistent local air mass factor (AMF) algorithm which converts the line-of-sight 'slant' columns to vertical columns for the period of 2003-2010. The local AMF was calculated using altitude-dependent scattering weights computed from a radiative transfer model (LIDORT) with state-of-art a priori parameters, weighted by relative vertical SO2 profiles (shape factor) determined locally with a global atmospheric chemical model (GEOS-Chem). The derived vertical columns and modeled vertical SO2 profiles were compared to measurements from aircraft campaigns in China. Trends of the long-term SO2 columns showed discrepancies between different regions in China: SO2 columns increased fast during 2003-2007 and then decreased by ~30% in 2010 in North China Plain; continuous increase of SO2 columns were found in Southwest of China with only a slight decrease in 2008 due to the global economic recession. The trends of SO2 columns were further compared to a unit-based power plant emission inventory to evaluate the effectiveness of power plant SO2 emission reductions related to the wide-spread installations of flue-gas desulfurization (FGD) devices since 2005 in China. The combinations of NO2 and SO2 measurements were used to examine the operation and efficiency of the FGD devices in power plants.

Zhang, Q.; Wang, S.; Martin, R. V.; He, K.; Richter, A.; Krotkov, N. A.; Philip, S.; Wang, T.

2011-12-01

290

Absorption removal of sulfur dioxide by falling water droplets in the presence of inert solid particles  

NASA Astrophysics Data System (ADS)

An experimental analysis of the absorption removal of sulfur dioxide by the free falling water droplets containing the inert solid particles is presented. The wheat flour powder is introduced as the inert solid particles. Tests with and without the flour powder in the water droplets are examined. The mass fluxes and mass transfer coefficients of SO 2 for the cases with and without the flour powder are compared to elucidate the effects of the inert solid particles contained in the water droplets on the gas absorption. The results indicate aignificant difference between the two cases for the concentrations of the flour powder in the absorbent droplets ( Cs) within the ranges of the experimental conditions, namely 0.1 to 10 wt% flour powder in the absorbent droplets. In general, the inert solid particles of the flour powder as the impurities in the water droplets tend to decrease the SO 2 absorption rate for the experimental absorption system under investigation. Various values of Cs cause various levels of the interfacial resistance and affect the gas absorption rate. The interfacial resistance is recognized by introducing an interfacial mass transfer coefficient ks with its reciprocal being proportional to the magnitude of the interfacial resistance. The values of 1/ ks may be computed by the use of the equation 1/ ks=(1/ KOLs-1/ KOL), where KOLs and KOL are the overall liquid-phase mass transfer coefficients with and without the inert solid particles, respectively. The values of ks with Cs of 0.1 to 10 wt% are about 0.295-0.032 cms -1 for absorbing 1000-3000 ppmv SO 2 with the water droplets. This kind of information is useful for the SO 2 removal and the information of acid rain that the impurities of the inert solid particles contaminate the water droplets.

Liu, I.-Hung; Chang, Ching-Yuan; Liu, Su-Chin; Chang, I.-Cheng; Shih, Shin-Min

291

Sulfur Dioxide Plume During the Continuing Eruption of Mt. Etna, Italy  

NASA Technical Reports Server (NTRS)

The current eruption of Mt. Etna started on July 17, and has continued to the present. This ASTER image was acquired on Sunday, July 29 and shows the sulfur dioxide plume (in purple) originating form the summit, drifting over the city of Catania, and continuing over the Ionian Sea. ASTER's unique combination of multiple thermal infrared channels and high spatial resolution allows the determination of the thickness and position of the SO2 plume. The image covers an area of 24 x 30 km.

The image is centered at 37.7 degrees north latitude, 15 degrees east longitude.

Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) is one of five Earth-observing instruments launched December 18, 1999, on NASA's Terra satellite. The instrument was built by Japan's Ministry of International Trade and Industry. A joint U.S./Japan science team is responsible for validation and calibration of the instrument and the data products. Dr. Anne Kahle at NASA's Jet Propulsion Laboratory, Pasadena, California, is the U.S. science team leader; Moshe Pniel of JPL is the project manager. ASTER is the only high-resolution imaging sensor on Terra. The primary goal of the ASTER mission is to obtain high-resolution image data in 14 channels over the entire land surface, as well as black and white stereo images. With revisit time of between 4 and 16 days, ASTER will provide the capability for repeat coverage of changing areas on Earth's surface.

The broad spectral coverage and high spectral resolution of ASTER will provide scientists in numerous disciplines with critical information for surface mapping and monitoring dynamic conditions and temporal change. Examples of applications include monitoring glacial advances and retreats, potentially active volcanoes, thermal pollution, and coral reef degradation; identifying crop stress; determining cloud morphology and physical properties; evaluating wetlands; mapping surface temperature of soils and geology; and measuring surface heat balance.

2001-01-01

292

Effects of ozone and sulfur dioxide on phyllosphere fungi from three tree species.  

PubMed

Short-term effects of ozone (O(3)) on phyllosphere fungi were studied by examining fungal populations from leaves of giant sequoia (Sequoiadendron giganteum (Lindl.) Buchholz) and California black oak (Quercus kelloggii Newb.). Chronic effects of both O(3) and sulfur dioxide (SO(2)) were studied by isolating fungi from leaves of mature Valencia orange (Citrus sinensis L.) trees. In this chronic-exposure experiment, mature orange trees were fumigated in open-top chambers at the University of California, Riverside, for 4 years with filtered air, ambient air plus filtered air (1:1), ambient air, or filtered air plus SO(2) at 9.3 parts per hundred million. Populations of Alternaria alternata (Fr.) Keissler and Cladosporium cladosporioides (Fres.) de Vries, two of the four most common fungi isolated from orange leaves, were significantly reduced by chronic exposure to ambient air. In the short-term experiments, seedlings of giant sequoia or California black oak were fumigated in open-top chambers in Sequoia National Park for 9 to 11 weeks with filtered air, ambient air, or ambient air plus O(3). These short-term fumigations did not significantly affect the numbers of phyllosphere fungi. Exposure of Valencia orange trees to SO(2) at 9.3 parts per hundred million for 4 years reduced the number of phyllosphere fungi isolated by 75% compared with the number from the filtered-air treatment and reduced the Simpson diversity index value from 3.3 to 2.5. A significant chamber effect was evident since leaves of giant sequoia and California black oak located outside of chambers had more phyllosphere fungi than did seedlings within chambers. Results suggest that chronic exposure to ambient ozone or SO(2) in polluted areas can affect phyllosphere fungal communities, while short-term exposures may not significantly disturb phyllosphere fungi. PMID:16347849

Fenn, M E; Dunn, P H; Durall, D M

1989-02-01

293

Advances in the Validation of Satellite-Based Maps of Volcanic Sulfur Dioxide Plumes  

NASA Astrophysics Data System (ADS)

The monitoring of volcanic gas emissions with gas cameras, spectrometer arrays, tethersondes, and UAVs presents new opportunities for the validation of satellite-based retrievals of gas concentrations. Gas cameras and spectrometer arrays provide instantaneous observations of the gas burden, or concentration along an optical path, over broad sections of a plume, similar to the observations acquired by nadir-viewing satellites. Tethersondes and UAVs provide us with direct measurements of the vertical profiles of gas concentrations within plumes. This presentation will focus on our current efforts to validate ASTER-based maps of sulfur dioxide plumes at Turrialba and Kilauea Volcanoes (located in Costa Rica and Hawaii, respectively). These volcanoes, which are the subjects of comprehensive monitoring programs, are challenging targets for thermal infrared (TIR) remote sensing due the warm and humid atmospheric conditions. The high spatial resolution of ASTER in the TIR (90 meters) allows us to map the plumes back to their source vents, but also requires us to pay close attention to the temperature and emissivity of the surfaces beneath the plumes. Our knowledge of the surface and atmospheric conditions is never perfect, and we employ interactive mapping techniques that allow us to evaluate the impact of these uncertainties on our estimates of plume composition. To accomplish this interactive mapping we have developed the Plume Tracker tool kit, which integrates retrieval procedures, visualization tools, and a customized version of the MODTRAN radiative transfer (RT) model under a single graphics user interface (GUI). We are in the process of porting the RT calculations to graphics processing units (GPUs) with the goal of achieving a 100-fold increase in the speed of computation relative to conventional CPU-based processing. We will report on our progress with this evolution of Plume Tracker. Portions of this research were conducted at the Jet Propulsion Laboratory, California Institute of Technology, under contract to the National Aeronautics and Space Administration.

Realmuto, V. J.; Berk, A.; Acharya, P. K.; Kennett, R.

2013-12-01

294

Prior exposure to ozone potentiates subsequent response to sulfur dioxide in adolescent asthmatic subjects  

SciTech Connect

The objective of this study was to test whether prior exposure to a low concentration of ozone (120 ppb) would condition airways in asthmatic subjects to respond to a subthreshold concentration of sulfur dioxide (100 ppb). Eight male and five female subjects 12 to 18 yr of age participated. They all had allergic asthma and exercise-induced bronchospasm. Subjects were exposed to three test atmosphere sequences during intermittent moderate exercise (a 45-min exposure to one pollutant followed by a 15-min exposure to the second pollutant). The sequences were: air followed by 100 ppb SO2, 120 ppb O3 followed by 120 ppb O3, and 120 ppb O3 followed by 100 ppb SO2. The pulmonary function measurements assessed were FEV1, total respiratory resistance (RT), and maximal flow (Vmax50). Air-SO2 and O3-O3 exposures did not cause significant changes in pulmonary function. On the other hand, exposure to 100 ppb SO2 after a 45-min exposure to 120 ppb O3 caused a significant (8%) decrease in FEV1 (p = 0.046), a significant (19%) increase in RT (p = 0.048), and a significant (15%) decrease in Vmax50 (p = 0.008). It is concluded that prior O3 exposure increased bronchial hyperresponsiveness in these subjects such that they responded to an ordinarily subthreshold concentration of SO2. These data suggest that assessment of pulmonary changes to single pollutant challenges overlooks the interactive effects of common coexisting or sequentially occurring air pollutants.

Koenig, J.Q.; Covert, D.S.; Hanley, Q.S.; van Belle, G.; Pierson, W.E. (Univ. of Washington, Seattle (USA))

1990-02-01

295

Correcting satellite-based infrared sulfur dioxide retrievals for the presence of silicate ash  

NASA Astrophysics Data System (ADS)

Previous studies have suggested that the presence of silicate ash may cause the 8.6-?m sulfur dioxide (SO2) retrieval to overestimate total column abundances and contribute to variations between ultraviolet and 8.6-?m SO2 estimates. Tested here is a volcanic aerosol forward model which allows the determination of transmission spectra. The forward model is embedded into a three-layer atmospheric radiative transfer model, based upon the moderate spectral resolution atmospheric transmittance algorithm (MODTRAN) radiative transfer code. This model is used to investigate the effects of silicate ash on the 8.6-?m SO2 retrieval from satellite data. Forward modeling of transmission through volcanic clouds enables us to evaluate the assumptions and errors of current retrievals. Four free variables, (1) effective radius, (2) variance, (3) number of particles, and (4) spectral refractive index, are used to determine the transmission and single scattering albedo at 7-13 ?m. Here we present simplistic characterizations of three eruptions, containing sulfates, ice, or andesitic ash using this forward model. The ash correction model based on the aerosol forward model is tested on the ash-rich lobe of the 19 February 2001 eruption plume of Mount Cleveland volcano using Moderate Resolution Imaging Spectroradiometer (MODIS) data. Uncorrected MODIS radiance values estimate 22 kt of SO2, while ash-corrected radiances estimate 17 kt. The minimal reduction in total SO2 indicates that previous variations in ultraviolet and 8.6-?m SO2 retrievals are unlikely to be due solely to the presence of ash.

Kearney, C. S.; Watson, I. M.

2009-11-01

296

Associations of London, England, daily mortality with particulate matter, sulfur dioxide, and acidic aerosol pollution  

SciTech Connect

During the extreme pollution episodes of 1952 and 1962 in London, England, excesses in daily mortality were clearly evident. In this study, we examined daily British Smoke, sulfur dioxide, acid aerosols, and weather variables for their short-term associations with daily mortality in the more typical (nonepisodic) winters of 1965-1972. Consideration of the acid aerosol data was of special interest because this chemical component has been suspected as a causal agent in past episodes. Temporal lag structures between the variables were examined after removal of long-term components from each series in order to obtain rational cross-correlations. Significant associations between same-day and lagged pollution variables and mortality were found. Alternative regression models with pollution and weather variables were also developed. The coefficients obtained were applied to the 1962 pollution episode to examine the continuity of the estimated slopes. The pollution-predicted deaths fit the observed deaths well, which supports the applicability of such deviation-derived coefficients to the absolute scale. These models were also employed to estimate mean excess daily deaths attributed hypothetically to air pollution. On average, mean effect ranged from 2-7% of all deaths during the nonepisodic winters in Greater London, but the 95% confidence intervals of these estimates overlapped for all model specifications examined. This estimated pollutant mixture effect cannot be attributed to a particular pollutant because of a lack of quantitative information on the relative downward biases caused by both analytical errors and errors in the spatial representativeness of each respective pollution index.

Ito, K.; Thurston, G.D.; Hayes, C.; Lippmann, M. (New York Univ. Medical Center, Tuxedo (United States))

1993-07-01

297

Experimental Inhibition of Carbonate Mineral Precipitation by Sulfur Dioxide: Implications for Early Mars  

NASA Astrophysics Data System (ADS)

Sulfur dioxide (SO2) is abundant in terrestrial volcanic emissions and was likely at least as abundant in early martian emissions. Recent photochemical studies indicate that during episodes of vigorous volcanic activity, the atmospheric lifetime of SO2 may have been sufficiently long for it to have helped maintain liquid water on the surface of Mars and perhaps to have regulated the climate through a negative feedback between the atmospheric abundance of SO2 and the rate of chemical weathering of silicate minerals. Here we show experimentally, that atmospheric SO2 concentrations three orders of magnitude lower than those required for it to have been of climatic importance would have had a major impact on the aqueous chemistry at the planet's surface and the precipitated mineral assemblage. Specifically, at near-neutral and even mildly alkaline pH, part-per-billion (ppb) concentrations of SO2 prevent the formation of calcium carbonate in favour of hannebachite - a hydrated calcium sulfite. Based on the results of recent photochemical studies, a volcanic outgassing flux ~300 times smaller than the modern terrestrial flux would have been enough to maintain such atmospheric concentrations. This implies that almost any period of active volcanism would have given rise to conditions under which carbonate precipitation is prevented at near-neutral pH. In the presence of ferrous iron, green rust, a possible precursor to phyllosilicate minerals, co-precipitates with hannebachite. This provides a possible explanation for the presence of phyllosilicates on early Noachian surfaces in the apparent absence of outcrop-scale carbonates. Finally, oxidation of the mineral assemblage precipitated in the experiments produces sulfates, iron oxides and acidity, consistent with observed mineral assemblages and with evidence for acid-sulfate dominated environments on late Noachian-early Hesperian surfaces.

Halevy, I.; Schrag, D. P.

2009-12-01

298

Leaf nitrogen dioxide uptake coupling apoplastic chemistry, carbon/sulfur assimilation, and plant nitrogen status.  

PubMed

Emission and plant uptake of atmospheric nitrogen oxides (NO + NO(2)) significantly influence regional climate change by regulating the oxidative chemistry of the lower atmosphere, species composition and the recycling of carbon and nutrients, etc. Plant uptake of nitrogen dioxide (NO(2)) is concentration-dependent and species-specific, and covaries with environmental factors. An important factor determining NO(2) influx into leaves is the replenishment of the substomatal cavity. The apoplastic chemistry of the substomatal cavity plays crucial roles in NO(2) deposition rates and the tolerance to NO(2), involving the reactions between NO(2) and apoplastic antioxidants, NO(2)-responsive germin-like proteins, apoplastic acidification, and nitrite-dependent NO synthesis, etc. Moreover, leaf apoplast is a favorable site for the colonization by microbes, which disturbs nitrogen metabolism of host plants. For most plant species, NO(2) assimilation in a leaf primarily depends on the nitrate (NO(3) (-)) assimilation pathway. NO(2)-N assimilation is coupled with carbon and sulfur (sulfate and SO(2)) assimilation as indicated by the mutual needs for metabolic intermediates (or metabolites) and the NO(2)-caused changes of key metabolic enzymes such as phosphoenolpyruvate carboxylase (PEPc) and adenosine 5'-phosphosulfate sulfotransferase, organic acids, and photorespiration. Moreover, arbuscular mycorrhizal (AM) colonization improves the tolerance of host plants to NO(2) by enhancing the efficiency of nutrient absorption and translocation and influencing foliar chemistry. Further progress is proposed to gain a better understanding of the coordination between NO(2)-N, S and C assimilation, especially the investigation of metabolic checkpoints, and the effects of photorespiratory nitrogen cycle, diverse PEPc and the metabolites such as cysteine, O-acetylserine (OAS) and glutathione. PMID:20628880

Hu, Yanbo; Sun, Guangyu

2010-10-01

299

Effects of Ozone and Sulfur Dioxide on Phyllosphere Fungi from Three Tree Species  

PubMed Central

Short-term effects of ozone (O3) on phyllosphere fungi were studied by examining fungal populations from leaves of giant sequoia (Sequoiadendron giganteum (Lindl.) Buchholz) and California black oak (Quercus kelloggii Newb.). Chronic effects of both O3 and sulfur dioxide (SO2) were studied by isolating fungi from leaves of mature Valencia orange (Citrus sinensis L.) trees. In this chronic-exposure experiment, mature orange trees were fumigated in open-top chambers at the University of California, Riverside, for 4 years with filtered air, ambient air plus filtered air (1:1), ambient air, or filtered air plus SO2 at 9.3 parts per hundred million. Populations of Alternaria alternata (Fr.) Keissler and Cladosporium cladosporioides (Fres.) de Vries, two of the four most common fungi isolated from orange leaves, were significantly reduced by chronic exposure to ambient air. In the short-term experiments, seedlings of giant sequoia or California black oak were fumigated in open-top chambers in Sequoia National Park for 9 to 11 weeks with filtered air, ambient air, or ambient air plus O3. These short-term fumigations did not significantly affect the numbers of phyllosphere fungi. Exposure of Valencia orange trees to SO2 at 9.3 parts per hundred million for 4 years reduced the number of phyllosphere fungi isolated by 75% compared with the number from the filtered-air treatment and reduced the Simpson diversity index value from 3.3 to 2.5. A significant chamber effect was evident since leaves of giant sequoia and California black oak located outside of chambers had more phyllosphere fungi than did seedlings within chambers. Results suggest that chronic exposure to ambient ozone or SO2 in polluted areas can affect phyllosphere fungal communities, while short-term exposures may not significantly disturb phyllosphere fungi.

Fenn, Mark E.; Dunn, Paul H.; Durall, Daniel M.

1989-01-01

300

Imaging DOAS detection of primary formaldehyde and sulfur dioxide emissions from petrochemical flares  

NASA Astrophysics Data System (ADS)

areas with a high number of petrochemical facilities are often struggling to meet current and future air quality standards. The Houston-Galveston area, for example, continues to be in noncompliance with the U.S. federal air quality standard of ozone, despite significant progress in mitigating air pollution. In recent years, the magnitude and role of primary emissions of ozone-forming chemicals, and in particular formaldehyde, from flares in petrochemical facilities have been discussed as a potential factor contributing to ozone formation. However, no direct observations of flare emissions of formaldehyde have thus far been reported. Here we present observations of formaldehyde and sulfur dioxide emissions from petrochemical flares in the Houston-Galveston area during the 2009 Formaldehyde and Olefin from Large Industrial Sources campaign using a new imaging differential optical absorption spectrometer (I-DOAS). Formaldehyde emissions from burning flares were observed directly above the flare stack and ranged from 0.2 to 8.5 kg/h. Unlit flares were found not to emit formaldehyde. SO2 emission rates from a burning acid gas flare ranged between 2 and 4 kg/h. None of the sampled flares coemitted HCHO and SO2. Comparison of the emission fluxes measured by the I-DOAS instrument with those from emission inventories and with fluxes calculated from plumes detected by the long-path DOAS over downtown Houston shows that the flares observed by the I-DOAS were relatively small. While burning flares clearly emit HCHO, a larger observational database is needed to assess the importance of flare emissions for ozone formation.

Pikelnaya, Olga; Flynn, James H.; Tsai, Catalina; Stutz, Jochen

2013-08-01

301

Interaction of sulfur dioxide with titanium-carbide nanoparticles and surfaces: A density functional study  

NASA Astrophysics Data System (ADS)

In the control of environmental pollution, metal carbides are potentially useful for trapping and destroying sulfur dioxide (SO2). In the present study, the density functional theory was employed to study the surface structures and electronic properties of the adsorbed SO2 on titanium carbides: metcar Ti8C12, nanocrystal Ti14C13, and a bulk TiC(001) surface. The geometries and orientations of SO2 were fully optimized on all these substrates. Our calculations show that, in spite of the high C/Ti ratio and C2 groups, metcar Ti8C12 exhibits extremely high activity towards SO2. The S-O bonds of SO2 spontaneously break on Ti8C12. The products of the decomposition reaction (S, O) interact simultaneously with Ti and C sites. The C atoms are not simple spectators, and their participation in the dissociation of SO2 is a key element for the energetics of this process. Nanocrystal Ti14C13 also displays a strong interaction with SO2. Although the dissociation of SO2 on Ti14C13 cannot proceed as easily as that on Ti8C12, it could occur by thermal activation even at very low temperature. SO2 is weakly bonded with the bulk TiC(001) surface. By thermal activation the dissociation of SO2 on a TiC(001) surface may also take place but it should be much more difficult than that on Ti14C13. Therefore, we suggest that the carbide nanoparticles (Ti8C12 and Ti14C13) should have special chemical activity towards SO2 removal associated with their ``magic'' structures.

Liu, Ping; Rodriguez, José A.

2003-11-01

302

Purification and properties of Escherichia coli dimethyl sulfoxide reductase, an iron-sulfur molybdoenzyme with broad substrate specificity.  

PubMed Central

Dimethyl sulfoxide reductase, a terminal electron transfer enzyme, was purified from anaerobically grown Escherichia coli harboring a plasmid which codes for dimethyl sulfoxide reductase. The enzyme was purified to greater than 90% homogeneity from cell envelopes by a three-step purification procedure involving extraction with the detergent Triton X-100, chromatofocusing, and DEAE ion-exchange chromatography. The purified enzyme was composed of three subunits with molecular weights of 82,600, 23,600, and 22,700 as identified by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The native molecular weight was determined by gel electrophoresis to be 155,000. The purified enzyme contained 7.5 atoms of iron and 0.34 atom of molybdenum per mol of enzyme. The presence of molybdopterin cofactor in dimethyl sulfoxide reductase was identified by reconstitution of cofactor-deficient NADPH nitrate reductase activity from Neurospora crassa nit-I mutant and by UV absorption and fluorescence emission spectra. The enzyme displayed a very broad substrate specificity, reducing various N-oxide and sulfoxide compounds as well as chlorate and hydroxylamine. Images

Weiner, J H; MacIsaac, D P; Bishop, R E; Bilous, P T

1988-01-01

303

Sulfur components analysis in hydrocarbon matrix by gas chromatography. [Methyl mercaptan; ethyl mercaptan; dimethyl sulfide; dimethyl disulfide; methyl ethyl sulfide; diethyl sulfide; diethyl disulfide; dipropyl sulfide  

SciTech Connect

The method described is for analysis of trace levels (0 to 200 ppM) of sulfur compounds. Material used for sample transfer lines, 1 cc gas sample loop and nickel column packed with oxi-propionitrile/Porasil C - Durapak 80 to 100 mesh. Two certified standard gas blends were used as calibration gases. Ultrahigh purity helium was used as the carrier gas. An effluent spliter is placed on the outlet of the column to send identical gas streams to the dual flame photometer and the flame ionization detector, thus allowing detection of components simultaneously. The temperature programming profile is described. Flow rates for the carrier gas and the flame gases were determined. The calibration blend is analyzed daily to assure optimum performance. Standard 2250-cc stainless steel sampling cylinders are used. Problems related to the analysis of hydrocarbon streams containing hydrogen sulfide and methyl mercaptan appear to be caused by the nature of the material in the sampling cylinders. 6 figures, 2 tables.

Puzic, O.

1983-09-01

304

On-line pervaporation-capillary electrophoresis for the determination of volatile acidity and free sulfur dioxide in wines.  

PubMed

Pervaporation has been coupled on-line to capillary electrophoresis (CE) by a simple interface consisting of a modified CE vial. The approach allows volatile analytes to be removed and injected into the capillary meanwhile the sample matrix remains in the pervaporator. By this approach volatile acidity and free sulfur dioxide have been simultaneously determined in wines. The detection limits (LODs) are 1.25 and 5.00 microg/mL, the quantification limits 4.12 and 16.50 microg/mL, and the linear dynamic ranges between LOD and 50 microg/mL and between 0.1 and 0.9 g/L for free sulfur dioxide and volatile acidity, respectively. The repeatability and within laboratory reproducibility, expressed as relative standard deviation (RSD), are 1.61% and 3.00% for free sulfur, and 3.35% and 4.58% for volatile acidity, respectively. The optimal pervaporation time and the time necessary for the individual separation-detection of the target analytes are 6 and 5 min, respectively. The analysis frequency is 7 h(-1) and the sample amount necessary is less than 7 mL. The proposed method and official methods for the analytes were applied to 32 wine samples. A two-tailed t-test was used to compare the methods, which yielded similar results. The errors, expressed as RSD for the two parameters, ranged between 1.3 and 4.1%. PMID:15880611

Ruiz-Jiménez, Jose; Luque de Castro, Maria D

2005-06-01

305

Reduction of sulfur dioxide by syngas to elemental sulfur over iron-based mixed oxide supported catalyts  

SciTech Connect

An iron-based supported catalyst has been developed for the reduction of SO{sub 2} by synthesis gas to obtain more than 97 % yield of elemental sulfur with a single stage reactor for 340-480{degrees}C (30-40 mesh particles), 440-580{degrees}C (d -{center_dot}3 mm x b {center_dot} 5 mm granules). Parametric studies on the performance of the catalyst have been conducted. The parameters studied include temperature, space velocity, molar ratio of H{sub 2} to CO, molar ratio of syngas to SO{sub 2} in the feed, and particle size of the catalyst. A lifetime test has been successfully performed. The mass balance of sulfur and carbon has been demonstrated. 21 refs., 19 figs., 3 tabs.

Jin, Yun; Yu, Qiquan; Chang, Shih-Ger [Univ. of California, Berkeley, CA (United States)

1997-12-31

306

Dimethyl sulfoxide (DMSO) as the sulfur source for the production of desulfurizing resting cells of Gordonia alkanivorans RIPI90A.  

PubMed

The sulfate repression of desulfurization (Dsz) phenotype represents a major barrier to the mass production of desulfurizing resting cells. This repression can be avoided by replacing sulfate with dibenzothiophene (DBT) as the main substrate for the 4S pathway. However, mass production of biocatalyst using DBT is impractical because of its high price, low water solubility, and growth inhibition by 2-hydroxybiphenyl (2-HBP), which is the end product of the 4S pathway. In this work, the results showed that readily bioavailable sulfur compounds led to repression of the desulfurization activity of Gordonia alkanivorans RIPI90A. However, the Dsz phenotype was expressed through the 4S pathway in the presence of DMSO as the sulfur source for growth. Resting cells grown on DMSO were more active than the resting cells grown on DBT. The growth rate of strain RIPI90A on DMSO was higher than when DBT was used as the sole sulfur source. DMSO concentration significantly influenced the growth pattern of the strain, and the highest growth rate was observed at a concentration of 200 microg ml(-1). Above this concentration, the growth rate gradually decreased. DBT was found to induce the Dsz phenotype, with no observed lag period, in cells grown on DMSO as the sole sulfur source. Prior to induction, the specific activity was detected as 1.4 micromol 2-HBP (g dry cell weight)(-1) h(-1), and following incubation (5 h) the highest specific activity was observed as 5.11 micromol 2-HBP (g dry cell weight)(-1 )h(-1). This study identified that resting cells can be prepared in a two-step process. First, resting cells can be produced using DMSO as the sulfur source for growth; in the second step, improvements to their desulfurizing activity can be made using DBT as an inducer. DMSO is recommended as an appropriate sulfur source for the mass production of G. alkanivorans RIPI90A. PMID:18310033

Mohebali, Ghasemali; Ball, Andrew S; Kaytash, Ashk; Rasekh, Behnam

2008-03-01

307

Dimethyl disulfide (DMDS) and dimethyl sulfide (DMS) emissions from biomass burning in Australia  

NASA Astrophysics Data System (ADS)

We identify dimethyl disulfide (DMDS) as the major reduced sulfur-containing gas emitted from bushfires in Australia's Northern Territory. Like dimethyl sulfide (DMS), DMDS is oxidized in the atmosphere to sulfur dioxide (SO2) and methane sulfonic acid (MSA), which are intermediates in the formation of sulfuric acid (H2SO4). The mixing ratios of DMDS and DMS were the highest we have ever detected, with maximum values of 113 and 35 ppbv, respectively, whereas background values were below the detection limit (10 pptv). Molar emission ratios relative to carbon monoxide (CO) were [1.6 +/- 0.1] × 10-5 and [6.2 +/- 0.3] × 10-6, for DMDS and DMS respectively, while molar emission ratios relative to carbon dioxide (CO2) were [4.7 +/- 0.4] × 10-6 and [1.4 +/- 0.4] × 10-7, respectively. Assuming these observations are representative of biomass burning, we estimate that biomass burning could yield up to 175 Gg/yr of DMDS (119 Gg S/yr) and 13 Gg/yr of DMS.

Meinardi, Simone; Simpson, Isobel J.; Blake, Nicola J.; Blake, Donald R.; Rowland, F. Sherwood

2003-05-01

308

Crystalline sulfur dioxide: Crystal field splittings, absolute band intensities and complex refractive indices derived from infrared spectra  

NASA Technical Reports Server (NTRS)

The infrared absorption spectra of thin crystalline films of sulfur dioxide at 90 K are reported in the 2700 to 450/cm region. The observed multiplicity of the spectral features in the regions of fundamentals is attributed to factor group splittings of the modes in a biaxial crystal lattice and the naturally present minor S-34, S-36, and O-18 isotopic species. Complex refractive indices determined by an iterative Kramers-Kronig analysis of the extinction data, and absolute band strengths derived from them, are also reported in this region.

Khanna, R. K.; Zhao, Guizhi

1986-01-01

309

Dynamics of Sulfur Dioxide in the Marine Boundary During Trace P  

NASA Astrophysics Data System (ADS)

An atmospheric pressure ionization mass spectrometer (APIMS) was employed to obtain 25 Hz sulfur dioxide (SO2) meausrements during the NASA Trace P field experiment. The APIMS was deployed on the NASA Wallops P-3B, which was equiped with the total air motion measurement system (TAMMS). The APIMS SO2 signal was recorded on the TAMMS data system to insure that the data was recorded on the same time base to allow processing of the data for eddy correlation measurements of SO2 with the vertical wind velocity from TAMMS. A preliminary estimate of the SO2 deposition velocity will be presented. At the high data sampling rates the dynamics of boundary layer could be studied for the effects on the SO2 distribution in conjunction with high data rate water vapor and temperature data from TAMMS. The turbulence data showed that the well mixed layer (within the planetary boundary layer) often was approximately 500 m with an intermittently turbulent layer above. The vertical distribution of SO2 was often constrained by the dynamics of these layers. In some cases the highest SO2 concentrations were in the well mixed layer and at other times the highest SO2 concentrations were in the less well mixed layer above. This partitioning could also be seen for water vapor and sometimes for carbon monoxide. In some cases it appeared that the continental boundary layer air had overrun the marine mixed layer during frontal progress through the experiment area. This partitioning can greatly affect the loss rates and mechanisms of SO2 in the absence of convection. When SO2 is predominantly above the well mixed layer, SO2 loss to the sea surface is primarily controlled by entraiment into the well mixed layer, which is a relatively slow process. When the SO2 is primarily in the well mixed layer its lifetime during transport can be much shorter than during transport aloft unless convection through the boundary layer occurs. The transport of SO2 in and around clouds was also observed during Trace P. The in situ data have been compared to 3-D modeling of the transport in an attempt to determine how cloud processing may explain the differences between the in situ data and the model results.

Thornton, D. C.; Tu, F.; Bandy, A. R.; Kim, M.; Thornhill, L.; Barrick, J. D.; Anderson, B.

2002-12-01

310

Sulfur chemistry over the central Arctic Ocean during the summer: Gas-to-particle transformation  

Microsoft Academic Search

Atmospheric gas-to-particle transformation of the oxidation products of dimethyl sulfide (DMS) was investigated over the central Arctic Ocean by using observational data and a coupled gas phase chemistry-aerosol dynamics model. Chemical compounds investigated were sulfuric acid (H2SO4(g)), methasulfonic acid (MSA(g)), and sulfur dioxide (SO2(g)) in the gas phase, and non-sea-salt sulfate (nss-SO42-) and MSA in the particulate phase. During the

Veli-Matti Kerminen; Caroline Leck

2001-01-01

311

Sulfur mass-independent fractionation patterns in the broadband UV photolysis of sulfur dioxide: Pressure and third body effects  

NASA Astrophysics Data System (ADS)

The production of mass-independent fractionation (MIF) in the products of the middle/far UV photolysis of SO 2 isotopologues has been linked to large S-MIF signatures observed in the pre-2.45 Ga rock record, and provides a valuable proxy for the evolution of atmospheric O 2. The origin of such large MIF signatures in photolytic products has recently been ascribed to the optical self-shielding of SO 2 isotopologues in photon-limited regions of the lower atmosphere. To better characterize the origin of such a signal we have performed pressure-variant broadband UV photolysis experiments of SO 2 and SO 2-He mixtures. Low pressure (~ 20 Torr) photolysis of SO 2 produces extractable sulfur with large ? 34S ? 120-180‰, ? 33S ~ 20‰, and ? 36S/? 33S ? - 2.5, while near atmospheric pressures produce sulfur with ? 33S ~ 2‰, and ? 36S/? 33S ? - 12. Similar experiments conducted with variable pressures of helium bath gas produce a similar diminution in ? 33S, and in both cases a ? 36S/? 33S ratio that is a linear function of pressure over several orders of magnitude. We postulate a photochemical and kinetic origin for the large S-MIF observed in these static cell experiments, produced from the excited state predissociative dynamics of SO 2, but cannot expressly rule out self-shielding as a contributor to fractionations observed here.

Masterson, Andrew L.; Farquhar, James; Wing, Boswell A.

2011-06-01

312

Sulfur X-Ray Absorption And Vibrational Spectroscopic Study of Sulfur Dioxide, Sulfite, And Sulfonate Solutions And of the Substituted Sulfonate Ions X(3)CSO(3-)(X = H, Cl, F)  

Microsoft Academic Search

Sulfur K-edge X-ray absorption near-edge structure (XANES) spectra have been recorded and the S(1s) electron excitations evaluated by means of density functional theory-transition potential (DFT-TP) calculations to provide insight into the coordination, bonding, and electronic structure. The XANES spectra for the various species in sulfur dioxide and aqueous sodium sulfite solutions show considerable differences at different pH values in the

E. Damian Risberg; L. Eriksson; J. Mink; L. G. M. Pettersson; M. Yu. Skripkin; M. Sandstrom

2009-01-01

313

The Use of Nahcolite Ore and Bag Filters For Sulfur Dioxide Emission Control  

Microsoft Academic Search

This paper describes some technical and economic aspects of the nahcolite ore injection process for the simultaneous removal of fly ash and sulfur oxides from stack gases. The process is capable of removing greater than 99% of the particulate matter and greater than 70% of the sulfur oxides present in such gases. In the process, nahcolite ore, a naturally occurring

J. M. Genco; H. S. Rosenberg; M. Y. Anastas; E. C. Rosar; J. M. Dulin

1975-01-01

314

Thermodynamic analysis of low-temperature carbon dioxide and sulfur dioxide capture from coal-burning power plants.  

PubMed

We discuss the possibility of capturing carbon dioxide from the flue gas of a coal-fired electrical power plant by cryogenically desublimating the carbon dioxide and then preparing it for transport in a pipeline to a sequestration site. Various other means have been proposed to accomplish the same goal. The problem discussed here is to estimate the "energy penalty" or "parasitic energy loss,' defined as the fraction of electrical output that will be needed to provide the refrigeration and that will then not be deliverable. We compute the energy loss (7.9-9.2% at 1 atm) based on perfect Carnot efficiency and estimate the achievable parasitic energy loss (22-26% at 1 atm) by incorporating the published coefficient of performance values for appropriately sized refrigeration or liquefaction cycles at the relevant temperatures. The analyses at 1 atm represent a starting point for future analyses using elevated pressures. PMID:23005487

Swanson, Charles E; Elzey, John W; Hershberger, Robert E; Donnelly, Russell J; Pfotenhauer, John

2012-07-01

315

Relaxed eddy accumulation measurements of ammonia, nitric acid, sulfur dioxide and particulate sulfate dry deposition near Tampa, FL, USA  

NASA Astrophysics Data System (ADS)

The relaxed eddy accumulation (REA) method was utilized to measure fluxes of key atmospheric species, specifically ammonia (NH3), nitric acid (HNO3), sulfur dioxide (SO2) and particulate sulfate (SO42-) to vegetation that is characteristic throughout the Tampa Bay Watershed. Three annular denuder systems (ADS), each consisting of two annular denuders and a filter pack in series, were deployed to accumulate gaseous constituents and fine-fraction particulates (Dp<2.5 µm) in updraft and downdraft eddies, as well as in the mid-draft velocity range. Relaxed eddy accumulation samples, which were analyzed by ion chromatography, and continuous meteorological data were collected during the May 2002 Bay Regional Atmospheric Chemistry Experiment (BRACE) near Sydney, FL. For the chemical species of current interest, concentrations were 1.64 ± 0.23 for NH3, 2.06 ± 0.24 for HNO3, 3.49 ± 0.50 for SO2 and 4.64 ± 0.31 µg m-3 for SO42-, and the deposition velocity (Vd) estimates for NH3, HNO3, SO2 and SO42- were 1.27 ± 3.65, 3.63 ± 1.47, 0.45 ± 0.98 and 0.42 ± 1.00 cm s-1, respectively. The results obtained confirm the expectation that the deposition of ammonia, nitric acid and particulate sulfate was controlled by aerodynamic and quasi-laminar layer resistances and that sulfur dioxide is relatively dependent upon stomatal conditions.

Toya Myles, La; Meyers, Tilden P.; Robinson, Larry

2007-07-01

316

A periodic orbit bifurcation analysis of vibrationally excited isotopologues of sulfur dioxide and water molecules: symmetry breaking substitutions.  

PubMed

Theoretical predictions and assignment of highly excited vibrational states and their organization is one of the most important challenges in molecular spectroscopy. A systematic procedure to investigate such problems is locating the principal families of periodic orbits that emanate from the stationary points of the molecule and then following their evolution with the total energy. This results in constructing continuation/bifurcation diagrams that assist in locating the critical bifurcation energies and to discover new types of vibrational modes. Another parameter that may influence the dynamics of a molecule is isotopic mass substitution. In this article, we investigate the effect of symmetry breaking by isotopic mass substitution of triatomic molecules with C(2v) symmetry in classical and quantum dynamics. Sulfur dioxide and water molecules in their ground electronic state are studied by employing accurate potential energy surfaces. Continuation/bifurcation diagrams of periodic orbits are constructed by varying the energy and the mass of one oxygen atom of sulfur dioxide and one hydrogen atom of a water molecule. The transition from normal-to-local mode vibrations is studied in terms of a pitchfork to a center-saddle elementary bifurcation of periodic orbits. The results presented in this article aim to help the assignment of experimentally obtained spectra. PMID:20825241

Mauguiere, Frederic; Rey, Michael; Tyuterev, Vladimir; Suarez, Jaime; Farantos, Stavros C

2010-09-16

317

Increased thiol biosynthesis of transgenic poplar expressing a wheat O -acetylserine(thiol) lyase enhances resistance to hydrogen sulfide and sulfur dioxide toxicity  

Microsoft Academic Search

O-acetylserine(thiol) lyase (OASTL), a key enzyme of the plant sulfur assimilatory pathway, catalyses the formation of cysteine\\u000a from sulfide and O-acetylserine. Transgenic hybrid poplar (Populus sieboldi × P. grandidentata ‘Y63’) plants expressing cys1, encoding a wheat cytosolic OASTL, were developed in order to examine the role of this enzyme in thiol production following\\u000a hydrogen sulfide or sulfur dioxide exposure and in the

Michimi Nakamura; Masato Kuramata; Isao Kasugai; Midori Abe; Shohab Youssefian

2009-01-01

318

Adsorption and reaction of sulfur dioxide with Cu(110) and Cu(110)-p(2×1)-O  

NASA Astrophysics Data System (ADS)

On Cu(110)-p(2×1)-O at 300 K SO2(g) reacts stoichiometrically with O(a) to form a surface covered with both c(4×2)-SO3 and p(2×2)-SO3 structures. With heating SO2(g) evolves from the surface in distinct reaction-limited states at 384 K, 425 K, and 470 K, and the surface reverts to its initially oxidized state. On Cu(110), SO2(g) adsorbs molecularly below 300 K; upon annealing to 300 K, the sulfur dioxide disproportionates according to 3SO2(a)-->S(a)+2SO3(a) with concomitant desorption of excess SO2(a). The surface formed in this manner exhibits large c(2×2)-S domains which encompass scattered c(4×2)-SO3 and p(2×2)-SO3 structures in a 1:2 coverage ratio. After being annealed to 400 K, the surface exhibits large p(2×2)-SO3 domains surrounding smaller c(4×2)-SO3 and c(2×2)-S islands. Continued heating past 400 K results in decomposition of sulfite according to SO3(a)-->SO2(g)+O(a), evolving sulfur dioxide at 470 K and leaving the surface covered with atomic sulfur and oxygen. Real-time STM images show the mobility of oxygen at island boundaries and the mobility of sulfite amid the p(2×1)-O structures. STM measurements suggest that the sulfite occupy four-fold hollow sites.

Alemozafar, Ali R.; Guo, Xing-Cai; Madix, Robert J.

2002-03-01

319

40 CFR 60.4330 - What emission limits must I meet for sulfur dioxide (SO2)?  

Code of Federal Regulations, 2010 CFR

...from the affected source any gases that contain SO 2 in excess...not have access to natural gas and that the removal of sulfur compounds would cause more environmental...stationary combustion turbine any gases which contain SO 2...

2009-07-01

320

A Demonstration of Acid Rain and Lake Acidification: Wet Deposition of Sulfur Dioxide.  

ERIC Educational Resources Information Center

Introduces a science demonstration on the dissolution of sulfuric oxide emphasizing the concept of acid rain which is an environmental problem. Demonstrates the acidification from acid rain on two lake environments, limestone and granite. Includes safety information. (YDS)

Goss, Lisa M.

2003-01-01

321

Sulfur dioxide estimations in the planetary boundary layer using dispersion models and satellite retrievals  

NASA Astrophysics Data System (ADS)

The health and environmental conditions in the Central Andes city La Oroya, Peru, have been seriously damaged by the heavy metal mining activities in the region. The situation has been exacerbated by the complex topography, which prevents proper mixing and dissolution of particles and gases released into the atmosphere. Understanding how pollutants are dispersed in populated regions, especially in complex terrain, would help to create mitigation strategies. The present study uses CALPUFF and HYSPLIT dispersion/deposition models to estimate sulfur dioxide (SO2) dispersion from the main stack of the La Oroya metallurgical plant. Due to the lack of meteorological data in the area, the Weather Research and Forecasting model (WRF) is used with observational nudging for temperature, relative humidity, and wind fields of three surface meteorological stations specifically installed for the study. The pollutant dispersion models are sensitive to a precise estimation of the turbulent vertical transport of mass, energy and moisture in the low atmosphere; therefore, two planetary boundary layer (PBL) schemes are tested, the Mellor-Yamada-Janjic and Yonsei University models. The dispersion models are run and results compared with field measurements at La Oroya, and Huancayo. The observation-nudging and YSU scheme considerably improved the prognostic variables. CALPUFF and HYSPLIT models showed similar patterns; however, HYSPLIT overestimated SO2 concentrations for low PBLs. Moreover, recent enhancements on spectral, spatial and temporal resolution of atmospheric scanning sensors of chemical constituents from the space, have led to detecting trace gases of anthropogenic origin in the lower troposphere. This contribution also explores the SO2 level 2 dataset from Ozone Mapping Instrument (OMI), in conjunction with atmospheric optical depth and Angstrom coefficient data products, extracted from MODerate Resolution Imaging Spectroradiometer (MODIS) to estimate SO2 loads in the PBL for clear and turbid atmospheric conditions. A narrow temporal sampling (three days) with no clear atmospheres and best sensor viewing geometry are examined and compared with a pollutant dispersion and deposition model (CALPUFF) and field observations. The efficacy of the developed method is further examined incorporating synchronous wind vectors, and daily accumulated precipitation derived from Tropical Rainfall Measuring Mission (TRMM) data. The source and trajectories of SO2 concentrations are detected by satellite based observations, and the pollutant plume is correctly traced downwind. Then, the spatial patterns of SO2 loads are analyzed for clear atmospheres and optimal viewing conditions (for 55 samples found in 467 days) and compared with field measurements. A logarithmic model is found between in situ observations and OMI estimations. The correlation can be increased when Angstrom exponents are between 0.7 and 1 and a linear relationship obtained when very high SO2 loads are extracted. Results show that the spatio-temporal dynamics of SO2 as monitored from space is in agreement with both field measurements and CALPUFF, which takes into account topography and wind field patterns. The study concludes that anthropogenic pollutants, i.e., SO2, and its trajectory can be monitored from OMI sensor even for turbid sky conditions. Findings of the research have great potential in public health managements and predictions.

Zarauz, Jorge V.

322

Laboratory Measurments of the 3.7-20 cm Wavelength Opacity of Sulfur Dioxide and Carbon Dioxide under Simulated Conditions for the Deep Atmosphere of Venus  

NASA Astrophysics Data System (ADS)

In the past two decades, multiple observations of Venus have been made at X band (3.6 cm) using the Jansky Very Large Array (VLA) and maps have been created of the 3.6 cm emission from Venus. Since the emission morphology is related both to surface features and to deep atmospheric absorption from CO2 and SO2 (see, e.g., Butler et al., Icarus 154, 2001), knowledge of the microwave absorption properties of sulfur dioxide in a carbon dioxide atmosphere under conditions for the deep atmosphere of Venus is required for proper interpretation. Except for a single measurement campaign conducted at a single wavelength (3.2 cm) over 40 years ago (Ho et al., JGR 71, 1966), no measurements of the centimeter-wavelength properties of any Venus atmospheric constituent have been conducted under conditions characteristic of the deep atmosphere (pressures from 10-92 Bars and temperatures from 400-700 K). New measurements of the microwave properties of SO2 and CO2 at wavelengths from 3.7-20 cm are now being conducted under simulated conditions for the deep atmosphere of Venus, using a new high-pressure system. Initial results from this measurement campaign conducted at 430 K and at pressures up to 92 Bars will be presented. This work is supported by the NASA Planetary Atmospheres Program under Grant NNX11AD66G.

Steffes, Paul G.; Barisich, C.

2012-10-01

323

[Significance of endogenous sulfur dioxide in the regulation of cardiovascular system].  

PubMed

Since the 1980's nitric oxide (NO), carbon monoxide (CO) and hydrogen sulfide (H(2)S), the endogenous gas molecules produced from metabolic pathway, have been realized as signal molecules to be involved in the regulation of body homeostasis and to play important roles under physiological and pathophysiological conditions. The researches on these endogenous gas signal molecules opened a new avenue in life science. To explore the new member of gasotransmitter family, other endogenous gas molecules which have been regarded as metabolic waste up to date, and their biological regulatory effects have been paid close attention to in the current fields of life science and medicine. Sulfur dioxide (SO(2)) can be produced endogenously from normal metabolism of sulfur-containing amino acids. L-cysteine is oxidized via cysteine dioxygenase to L-cysteinesulfinate, and the latter can proceed through transamination by glutamate oxaloacetate transaminase (GOT) to beta-sulfinyl pyruvate which decomposes spontaneously to pyruvate and SO(2). In mammals, activated neutrophils by oxidative stress can convert H(2)S to sulfite through a reduced form of nicotinamide-adenine dinucleotide phosphate (NADPH) oxidase-dependent process. The authors detected endogenous production of SO(2) in all cardiovascular tissues, including in heart, aorta, pulmonary artery, mesenteric artery, renal artery, tail artery and the plasma SO(2) content. As the key enzyme producing SO(2), GOT mRNA in cardiovascular system was detected and found to be located enriched in endothelial cells and vascular smooth muscle cells near the endothelial layer. When the normal rats were treated with hydroxamate(HDX), a GOT inhibitor, at a dose of 3.7 mg/kg body weight, the blood pressure (BP) went high markedly, the ratio of wall thickness to lumen radius was increased by 18.34%, and smooth muscle cell proliferation was enhanced. The plasma SO(2) level in the rats injected with 125 micromol/kg body weight SO(2) donor was increased to 721.98+/-30.11 micromol/L at the end of 30 seconds, while the blood pressure was decreased to the lowest point 65.0+/- 4.9 mm Hg at the end of 1 minute. The above results showed that endogenous SO(2) might be involved in the maintenance of blood pressure and normal vascular structure. In spontaneous hypertensive rat (SHR) animal model, exogenous supplement of SO(2) donor decreased the BP, the media cross-sectional area, and pressure of the media and the ratio of wall thickness to lumen radius in the SHR. Moreover, the proliferative index of aortic smooth muscle cells was decreased in the SHR treated with SO(2) donor compared with that in SHR. The above data showed that SO(2) could prevent the aortic structural remodeling by inhibiting the proliferation of aortic smooth muscle cells. The authors observed the direct vasorelaxant effects of SO(2) on the aortic ring pre-treated with norepinephrine (NE). SO(2) donor at a concentration of 25-100 micromol/L relaxed the aortic ring temporarily and slightly, but SO(2) donor at a concentration of 1-12 mmol/L induced relaxation of the ring in a concentration-dependent manner. Administration with nicardipine, an L-type calcium channel blocker other than glibenclamide, an ATP sensitive potassium channel (K(ATP) channel) blocker or removal of vascular endothelium could decrease the SO(2)-induced vasorelaxation. In hypoxic pulmonary hypertension animal model, SO(2) donor decreased the mean pulmonary artery pressure and the systolic pulmonary artery pressure (P<0.01), respectively as compared with hypoxic group, and alleviated obviously the hypoxic pulmonary vascular structural remodeling. The percentage of muscularized arteries of small pulmonary vessels was significantly decreased in hypoxia+SO(2) donor-treated rats compared with that of hypoxic rats (P<0.01), while the percentage of non-muscularized vessels was obviously higher in hypoxia with SO(2) donor-treated rats than that of hypoxic rats (P<0.01). Similarly, SO(2) obviously decreased relative media area and relative media thickness of small musculariz

Jin, Hong Fang; DU, Shu Xu; Zhao, Xia; Zhang, Su Qing; Tian, Yue; Bu, Ding Fang; Tang, Chao Shu; DU, Jun Bao

2007-08-18

324

Dimethyl disulfide produced by the naturally associated bacterium bacillus sp B55 promotes Nicotiana attenuata growth by enhancing sulfur nutrition.  

PubMed

Bacillus sp B55, a bacterium naturally associated with Nicotiana attenuata roots, promotes growth and survival of wild-type and, particularly, ethylene (ET)-insensitive (35)S-ethylene response1 (etr1) N. attenuata plants, which heterologously express the mutant Arabidopsis thaliana receptor ETR1-1. We found that the volatile organic compound (VOC) blend emitted by B55 promotes seedling growth, which is dominated by the S-containing compound dimethyl disulfide (DMDS). DMDS was depleted from the headspace during cocultivation with seedlings in bipartite Petri dishes, and (35)S was assimilated from the bacterial VOC bouquet and incorporated into plant proteins. In wild-type and (35)S-etr1 seedlings grown under different sulfate (SO(4)(-2)) supply conditions, exposure to synthetic DMDS led to genotype-dependent plant growth promotion effects. For the wild type, only S-starved seedlings benefited from DMDS exposure. By contrast, growth of (35)S-etr1 seedlings, which we demonstrate to have an unregulated S metabolism, increased at all SO(4)(-2) supply rates. Exposure to B55 VOCs and DMDS rescued many of the growth phenotypes exhibited by ET-insensitive plants, including the lack of root hairs, poor lateral root growth, and low chlorophyll content. DMDS supplementation significantly reduced the expression of S assimilation genes, as well as Met biosynthesis and recycling. We conclude that DMDS by B55 production is a plant growth promotion mechanism that likely enhances the availability of reduced S, which is particularly beneficial for wild-type plants growing in S-deficient soils and for (35)S-etr1 plants due to their impaired S uptake/assimilation/metabolism. PMID:23903320

Meldau, Dorothea G; Meldau, Stefan; Hoang, Long H; Underberg, Stefanie; Wünsche, Hendrik; Baldwin, Ian T

2013-07-01

325

Formation of Secondary Organic Aerosol from Irradiated a -Pinene/Tolueme/NOx Mixtures and the Effect of Isoprene and Sulfur Dioxide  

EPA Science Inventory

Secondary organic aerosol (SOA) was generated by irradiating a series of a-pinene/toluene/NOx mixtures in the absence and presence of isoprene or sulfur dioxide. The purpose of the experiment was to evaluate the extent to which chemical perturbations to this base-case (a-pinene/...

326

INTERMEDIATE-RANGE GRID MODEL AND USER'S GUIDE FOR ATMOSPHERIC SULFUR DIOXIDE AND SULFATE CONCENTRATIONS AND DEPOSITIONS - WISCONSIN POWER PLANT IMPACT STUDY  

EPA Science Inventory

The UWATM-SOX computer model was developed to address the acid rain problem on a mesoscale. It predicts sulfur dioxide (SO2) and sulfate (SO4) ambient air concentrations and ground level dry and wet (rain or snow) depositions given certain emission and meteorological input data. ...

327

Synthesis of the C(1)-C(11) polyene fragment of apoptolidin with a new sulfur dioxide-based organic chemistry.  

PubMed

A new sulfur dioxide-based organic chemistry has been developed as a novel approach for the stereoselective synthesis of polyene fragments based on our one-pot, four-component synthesis of polyfunctional epsilon-alkanesulfonyl-gamma,delta-unsaturated ketones. The flexibility and efficiency of this methodology are illustrated by the preparation of (+)-methyl (2E,4E,6E,8R,9S)-9-{[(tert-butyl)dimethylsilyl]oxy}-2,4,6,8-tetramethyl-11-(triethylsilyl)undeca-2,4,6-trien-10-ynoate, a synthetic intermediate of Nicolaou and co-workers, that corresponds to the C(1)-C(11) fragment of apoptolidin, which was used by the authors in their total synthesis of this promising anticancer agent. PMID:15954151

Bouchez, Laure C; Vogel, Pierre

2005-08-01

328

Quartz-enhanced photoacoustic spectroscopy-based sensor system for sulfur dioxide detection using a CW DFB-QCL  

NASA Astrophysics Data System (ADS)

Sulfur dioxide (SO2) trace gas detection based on quartz-enhanced photoacoustic spectroscopy (QEPAS) using a continuous wave, distributed feedback quantum cascade laser operating at 7.24 ?m was performed. Influence of water vapor addition on monitored QEPAS SO2 signal was also investigated. A normalized noise equivalent absorption coefficient of NNEA (1?) = 1.21 × 10-8 cm-1 W Hz-1/2 was obtained for the ? 3 SO2 line centered at 1,380.93 cm-1 when the gas sample was moisturized with 2.3 % H2O. This corresponds to a minimum detection limit (1?) of 63 parts per billion by volume for a 1 s lock-in time constant.

Waclawek, J. P.; Lewicki, R.; Moser, H.; Brandstetter, M.; Tittel, F. K.; Lendl, B.

2014-04-01

329

Appearance of compound cilia in the nasal mucosa of normal human subjects following acute, in vivo exposure to sulfur dioxide  

SciTech Connect

Electron microscopic examination of ultrathin sections of ciliated nasal epithelium obtained from seven normal, healthy human volunteers indicated increases in the prevalence of compound cilia following controlled, acute exposure to 0.75 ppm sulfur dioxide (SO/sub 2/). Morphometric analyses of the specimens confirmed a statistically significant association between SO/sub 2/ exposure and compounding of nasal epithelial cilia in four of the seven subjects. Concomitant freeze-fracture replicas prepared from these samples also revealed the occurrence of compound cilia with accompanying evidence of abnormal ciliary membrane ultrastructure in the nasal epithelium. These studies indicate that SO/sub 2/ may be implicated as a causative agent in ciliary compounding in the upper respiratory tract and that compound cilia represent a form of acquired ciliary defect which may serve as a readily quantifiable marker of epithelial injury.

Carson, J.L.; Collier, A.M.; Hu, S.C.; Smith, C.A.; Stewart, P.

1987-02-01

330

40 CFR 60.4330 - What emission limits must I meet for sulfur dioxide (SO2)?  

Code of Federal Regulations, 2010 CFR

...from the affected source any gases that contain SO2 in excess...not have access to natural gas and that the removal of sulfur compounds would cause more environmental...stationary combustion turbine any gases which contain SO2 in...

2010-07-01

331

Removal of Sulfur Dioxide by a Slurry of Jordanian Oil Shale Ash  

Microsoft Academic Search

This work presents a study on the capacity of oil shale ash to remove sulphur dioxide from air streams before escaping into the atmosphere. Slurries of different concentrations of this ash showed an uptake capacity of 4 × 10 mol SO2\\/g ash obtained after 250 sec. This value increases with the increase of solution pH, temperature, and ash concentration, and

A. M. Al-Harahsheh; R. A. Shawabkeh; M. S. Al-Harahsheh; M. M. Batiha

2011-01-01

332

Models for the Centimeter-Wavelength Opacity of Sulfur Dioxide and Carbon Dioxide based on Laboratory Measurements Conducted under Simulated Conditions for the Deep Atmosphere of Venus  

NASA Astrophysics Data System (ADS)

In the past two decades, multiple observations of Venus have been made at X band (3.6 cm) using the Jansky Very Large Array (VLA), and maps have been created of the 3.6 cm emission from Venus. Since the emission morphology is related both to surface features and to deep atmospheric absorption from CO2 and SO2 (see, e.g., Butler et al., Icarus 154, 2001), knowledge of the microwave absorption properties of sulfur dioxide in a carbon dioxide atmosphere under conditions for the deep atmosphere of Venus is required for proper interpretation. Initial measurements of the centimeter-wavelength (3.7-20 cm) of SO2 and CO2 under simulated conditions for the deep atmosphere of Venus, conducted using a new high-pressure system operating at 430 K and at pressures up to 92 Bars, were presented by Steffes and Barisich (DPS-2012, B.A.A.S., v.44, p.241). Over the past year, we have completed this measurement campaign for temperatures up to 550 K, so as to better understand the effects of SO2 and CO2 on the microwave emission from the Venus boundary layer. Results indicate that the model for the centimeter-wavelength opacity from pure CO2 (developed over 40 years ago -- Ho et al., JGR 71, 1966), is valid over the entire centimeter-wavelength range under simulated conditions for the deep atmosphere of Venus. Additionally, the laboratory results indicate that the model for the centimeter-wavelength opacity of SO2 in a CO2 atmosphere from Suleiman et al. (JGR-Planets, 101, Feb. 1996) can reliably be used under conditions of the deep atmosphere of Venus with the modifications described in this paper . This work is supported by the NASA Planetary Atmospheres Program under Grant NNX11AD66G.

Steffes, Paul G.; Shahan, P. M.

2013-10-01

333

Short-term exposure to 0. 3 ppm nitrogen dioxide does not potentiate airway responsiveness to sulfur dioxide in asthmatic subjects  

SciTech Connect

Whether short-term exposure to low levels of nitrogen dioxide (NO2) enhances airway responsiveness in asthmatic subjects is controversial. Because it is well established that asthma is associated with increased airway responsiveness to another common air pollutant, sulfur dioxide (SO2), we examined whether short-term exposure of asthmatic subjects to 0.3 ppm NO2 potentiates airway responsiveness to inhaled SO2. We exposed nine subjects with clinically stable asthma to 0.3 ppm NO2 or filtered air in an environmental room for 30 min on 2 separate days at least 1 wk apart in a double-blind, randomized fashion. A questionnaire about common symptoms related to inhaled irritants was completed before and immediately after each exposure. Each subject exercised (60 to 80 W) on a cycloergometer during the first 20 min of each exposure. We measured specific airway resistance (SRaw) and FEV1/FVC before, 5 min after, and 1 h after completion of the air or NO2 exposure. The single-breath nitrogen test (SBN2) was also performed before and 1 h after completion of the air or NO2 exposures and closing volume was determined; subsequently, SO2 dose-response curves (0.25 to 4.0 ppm) were performed via a mouthpiece. Each dose of SO2 was inhaled at a minute ventilation of 20 L/min for 4 min and was doubled until SRaw increased by at least 8 U above baseline. The dose of SO2 required to provoke an increase in SRaw of 8 U above baseline was determined by linear interpolation from the dose-response curve (PD8Uso2).

Rubinstein, I.; Bigby, B.G.; Reiss, T.F.; Boushey, H.A. Jr. (Univ. of California, San Francisco (USA))

1990-02-01

334

Plotting of Acid Rain and Sulfur Dioxide Pollution Control Zones and Integrated Control Planning in China  

Microsoft Academic Search

The distribution and characteristics of acid rain and SO2 pollution were presented, indicating that the areas with sulfur deposition over critical loads reached 21.9% of the territory in 1995. In order to control the acid rain and SO2 pollution effectively, the Acid Rain Control Zone and SO2 Pollution Control Zone (Two Control Zones for short) were designated based on the

Jiming Hao; Shuxiao Wang; Bingjiang Liu; Kebin He

2001-01-01

335

Sulfur dioxide flux into leaves of Geranium carolinianum L. : evidence for a nonstomatal or residual resistance  

Microsoft Academic Search

The concurrent exchange of SOâ and HâO vapor between the atmosphere and foliage of Geranium carolinianum was investigated using a whole-plant gas exchange chamber. Total leaf flux of SOâ was partitioned into leaf surface and internal fractions. The emission rate of SOâ-induced HâS was measured to develop a net leaf budget for atmospherically derived sulfur. Stomatal resistance to SOâ flux

G. E. Jr. Taylor; D. T. Tingey

1983-01-01

336

21 CFR 184.1095 - Sulfuric acid.  

Code of Federal Regulations, 2013 CFR

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

2013-04-01

337

The production of sulfate particles through the radiolytic oxidation of sulfur dioxide  

SciTech Connect

The production of hydroxyl radicals by the radiolytic decomposition of water vapor following alpha decay of {sup 222}Rn can be used to produce an ultrafine sulfuric acid aerosol in the presence of SO{sub 2}. In the past, the production of this aerosol appeared to have a limiting threshold in as much as sufficient conversion of SO{sub 2} to SO{sub 4} must be attained to achieve the concentration required for nucleation. This appeared to occur when the bulk average acidity reached an adequately high value. The threshold curve for the onset of the sulfuric acid aerosol formation is a function of the H{sub 2}O, SO{sub 2} and Rn concentrations. The hydroxyl radical formation is dependent on the H{sub 2}O and Rn concentrations. The mass conversion rate of SO{sub 2} to H{sub 2}SO{sub 4} has been studied by measuring the airborne H{sub 2}SO{sub 4} concentration by ion chromatography after it has been collected on a filter and leached into solution. 39 refs., 9 figs.

Karpen-Hayes, K.

1991-09-13

338

Vertical distribution of dimethylsulfide, sulfur dioxide, aerosol ions, and radon over the northeast Pacific Ocean  

NASA Technical Reports Server (NTRS)

The vertical distributions, in temperate latitudes, of dimethylsulfide (DMS), SO2, radon, methanesulfonate (MSA), nonsea-salt sulfate (nss-sulfate), and aerosol Na(+), NH4(+), and NO(-) ions were determined in samples collected by an aircraft over the northeast Pacific Ocean during May 3-12, 1985. DMS was also determined in surface seawater. It was found that DMS concentrations, both in seawater and in the atmospheric boundary layer, were significantly lower than the values reported previously for subtropical and tropical regions, reflecting the seasonal variability in the temperate North Pacific. The vertical profiles of DMS, MSA, SO2, and nss-sulfate were found to be strongly dependent on the convective stability of the atmosphere and on air mass origin. Biogenic sulfur emissions could account for most of the sulfur budget in the boundary layer, while the long-range transport of continentally derived air masses was mainly responsible for the elevated levels of both SO2 and nss-sulfate in the free troposphere.

Andreae, M. O.; Berresheim, H.; Andreae, T. W.; Kritz, M. A.; Bates, T. S.

1988-01-01

339

Electrophoresis pattern of serum from mice exposed to different concentrations of sulfur dioxide  

NASA Technical Reports Server (NTRS)

Three day old mice were continuously exposed to sulphur dioxide concentrations at 0ppm, 0.05ppm, 0.15ppm and 1ppm for eight weeks. At the end of the experiment, blood samples were collected and centrifuged for electrophoresis studies of the serum in 5 percent acrylamide gel. The length of bands of different serum proteins from the SO2 exposed mice was at a variance as compared with the length of bands from the control exposed mice and alpha-1 band seems to be missing from the serum of SO2 exposed mice.

Singh, J.

1977-01-01

340

Effects of ozone and sulfur dioxide on forage and range species. Volume 2. Under simulated grazing (defoliation). Final report Oct 80-Jun 83  

SciTech Connect

Soft chess and broadleaf filaree plants were grown in pots and exposed to sulfur dioxide in open-top field chambers. Plants were fumigated with 0.0 ppm, 0.1 ppm or 0./sub 2/'' ppm sulfur dioxide for six hours per day, five days per week over an 18 week period. Plants were harvested at week 9, week 13 and week 18. Defoliation treatments were carried out on one-half of the plants. Chronic exposure of nonclipped soft chess to SO/sub 2/ led to reduced yield. Clipping of soft chess usually cancelled the SO/sub 2/ effects. Broadleaf filaree appeared more tolerant to SO/sub 2/ than soft chess.

Younger, V.B.; Shropshire, F.M.; Thompson, C.R.

1983-06-30

341

Development of a countercurrent multistage fluidized-bed reactor and mathematical modeling for prediction of removal efficiency of sulfur dioxide from flue gases  

SciTech Connect

A bubbling countercurrent multistage fluidized-bed reactor for the sorption of sulfur dioxide by hydrated lime particles was simulated employing a two-phase model, with the bubble phase assumed to be in plug flow and with the emulsion phase either in plug flow (EGPF model) or in perfectly mixed flow (EGPM model). The model calculations were compared with experimental data in term of percentage removal efficiency of sulfur dioxide. Both models were applied to understand the influence of operating parameters on the reactor performance. The comparison showed that the EGPF model agreed well with the experimental data. From the perspective of use of a multistage fluidized-bed reactor as air pollution control equipment in industry, the model could be considered general enough for predicting the performance of reactors for gas-solid treatment.

Mohanty, C.R.; Malavia, G.; Meikap, B.C. [Indian Institute of Technology, Kharagpur (India). Dept. of Chemical Engineering

2009-02-15

342

Surface-enhanced Raman spectroscopy at transition metal-gas interfaces: Adsorption and reactions of sulfur dioxide on platinum-, rhodium-, and ruthenium-coated gold  

Microsoft Academic Search

Surface-enhanced Raman (SER) spectra obtained using 647-nm excitation are reported for the adsorption and oxidation of sulfur dioxide in flowing argon-based streams at ambient pressures and at 300 K on electrochemically roughened Au, and on Au surfaces modified by thin (2-3 monolayer) electrodeposited films of Pt, Rh, and Ru. The spectra were recorded by using a spectrograph\\/charge-coupled device (CCD) detector

T. Wilke; Xiaoping Gao; C. G. Takoudis; M. J. Weaver

1991-01-01

343

Replacement of Hazardous Chromium Impregnating Agent from Silver\\/Copper\\/Chromium-Impregnated Active Carbon Using Triethylenediamine to Remove Hydrogen Sulfide, Trichloromethane, Ammonia, and Sulfur Dioxide  

Microsoft Academic Search

Activated carbon (AC) is widely used as an effective adsorbent in many applications, including industrial-scale air purification systems and air filter systems in gas masks. In general, ACs without chemical impregnation are good adsorbents of organic vapors but poor adsorbents of low-molecular-weight or polar gases such as chlorine, sulfur dioxide (SO2), formaldehyde, and ammonia (NH3). Impregnated ACs modified with metallic

Li-Chun Wu; Ying-Chien Chung; Tracy Glenz; Lisa Brosseau; Richard Hoffbeck; Kyoko Yamashita; Naomichi Yamamoto; Atsushi Mizukoshi; Miyuki Noguchi; Yueyong Ni; Yukio Yanagisawa; Yongping Li; Guohe Huang; James Schwab; John Spicer; Kenneth Demerjian; Mark Gibson; Judith Guernsey; Stephen Beauchamp; David Waugh; Mathew Heal; Jeffrey Brook; Robert Maher; Graham Gagnon; Johnny McPherson; Barbara Bryden; Richard Gould; Liming Zhou; Philip Hopke; Weixiang Zhao; Elisabeth Hawley; Neven Kresic; Alexandra Wright; Michael Kavanaugh; Pat Saathoff; Amit Gupta; Ted Stathopoulos; Louis Lazure; ABM Khan; Nigel Clark; Mridul Gautam; W. Wayne; Gregory Thompson; Donald Lyons; Yu-Ming Kuo; Yasuhiro Fukushima

2009-01-01

344

Determination of free and total sulfur dioxide in wine samples by vapour-generation inductively coupled plasma–optical-emission spectrometry  

Microsoft Academic Search

Sulfur dioxide (SO2) is used as a preservative and stabilizer in wine production to prevent undesired biochemical processes in the must and the\\u000a final product. The concentration of SO2 is restricted by national regulations. There are two main forms of SO2 in wine—free (inorganic forms) and bound (fixed to organic compounds, e.g. aldehydes). Iodometric titration is commonly employed\\u000a for determination

Ji?í ?melík; Ji?í Machát; Eva Niedobová; Vít?zslav Otruba; Viktor Kanický

2005-01-01

345

Bisulfite and sulfite as derivatives of sulfur dioxide alters biomechanical behaviors of airway smooth muscle cells in culture.  

PubMed

Sulfur dioxide (SO2) is a common air pollutant that triggers asthmatic symptoms, but its toxicological mechanisms are not fully understood. Specifically, it is unclear how SO2 in vivo affects airway smooth muscle (ASM) cells of which the mechanics is known to ultimately mediate airway hyperresponsiveness (AHR) - a hallmark feature of asthma. To this end, we investigated the effects of bisulfite/sulfite (1:3 M/M in neutral fluid to simulate the in vivo derivatives of inhaled SO2 in the airways), on the viability, migration, stiffness and contractility of ASM cells cultured in vitro. The results showed that bisulfite/sulfite consistently increased viability, migration, F-actin intensity and stiffness of ASM cells in similar fashion as concentration increasing from 10(-4) to 10(-1)?mmol/L. However, bisulfite/sulfite increased the ASM cell contractility induced by KCl only at the concentration between 10(-4) and 10(-3)?mmol/L (p?

Song, Aijing; Lin, Feng; Li, Jianming; Liao, Qingfeng; Liu, Enmei; Jiang, Xuemei; Deng, Linhong

2014-02-01

346

Ground level concentration of sulfur dioxide at Kuwait`s major population centers during the oil-field fires  

SciTech Connect

During the Iraqi occupation, Kuwait`s oil wells were ignited. the fires were damaging to the country`s oil resources and air quality. The impact of the oil-field fires on the air quality was studied to determine the level of exposure to pollutants in major population centers. The period of July-September 1991 was selected for examination. A mathematical model was used to compute the ground-level concentration isopleths. The results of these computations are supported by significant concentrations measured and reported by the Environmental Protection Council, Kuwait. The ground-level concentrations of sulfur dioxide in the major population centers, whether measure or estimated, were less than the ambient standards of the U.S. Environmental Protection Agency`s air pollution index. The dispersive characteristics were classified according to wind conditions. The results of this assessment provide historical data on Kuwait`s oil fires and may be useful in assessing risks resulting from this catastrophe. 6 refs., 10 fig., 2 tab.

Al-Ajmi, D.N.; Marmoush, Y.R. [Kuwait Institute for Scientific Research (Kuwait)] [Kuwait Institute for Scientific Research (Kuwait)

1996-08-01

347

Sulfur dioxide-induced bronchoconstriction in asthmatics exposed for short durations under controlled conditions: a selected review  

SciTech Connect

Prior to 1980, essentially no health related effects had been observed for short-term ( < 1 hr) exposures to sulfur dioxide (SO/sub 2/) levels similar to those found in the ambient environment (= or < 1 ppm). In 1980 and 81, the results from several studies indicated that asthmatics' airways were substantially more responsive to SO/sub 2/ than those of nonasthmatic individuals and that, when combined with moderate exercise, significant bronchoconstriction resulted from exposures to as low as 0.5 ppm SO/sub 2/. Since then, a multitude of reports regarding short-term exposure of asthmatics to low SO/sub 2/ levels have appeared in the literature. From these studies, reflex bronchoconstriction, mast cell degranulation and other, yet unidentified, mechanisms were implicated in the induction of response. A broad range of responsiveness to SO/sub 2/ exists within the asthmatic population. Precise knowledge of factors involved in this variable responsiveness is lacking; differences in nonspecific airway sensitivity and severity of disease are suggested.

Horstman, D.H.

1987-11-01

348

The last decade of global anthropogenic sulfur dioxide: 2000-2011 emissions  

NASA Astrophysics Data System (ADS)

The evolution of global and regional anthropogenic SO2 emissions in the last decade has been estimated through a bottom-up calculation. After increasing until about 2006, we estimate a declining trend continuing until 2011. However, there is strong spatial variability, with North America and Europe continuing to reduce emissions, with an increasing role of Asia and international shipping. China remains a key contributor, but the introduction of stricter emission limits followed by an ambitious program of installing flue gas desulfurization on power plants resulted in a significant decline in emissions from the energy sector and stabilization of total Chinese SO2 emissions. Comparable mitigation strategies are not yet present in several other Asian countries and industrial sectors in general, while emissions from international shipping are expected to start declining soon following an international agreement to reduce the sulfur content of fuel oil. The estimated trends in global SO2 emissions are within the range of representative concentration pathway (RCP) projections and the uncertainty previously estimated for the year 2005.

Klimont, Z.; Smith, S. J.; Cofala, J.

2013-03-01

349

Sulfur dioxide emissions from combustion in china: from 1990 to 2007.  

PubMed

China has become the world's largest emitter of SO(2) since 2005, and aggressive deployment of flue gas desulfurization (FGD) at coal-fired power plants appeared in China when facing the formidable pressure of environment pollution. In this work, we estimate the annual emission from combustion sources at provincial levels in China from 1990 to 2007, with updated data investigations. We have implemented the method of transportation matrix to gain a better understanding of sulfur content of coal in consuming provinces, which in turn improved the inventory. The total emissions from combustion in 2007 were 28.3 Tg, half of which was contributed by coal-fired power plants. Meanwhile, the industrial boiler coal combustion and residential coal consumed in centralized heating were responsible for another 32% of the total emissions. From 1990 to 2007, annual SO(2) emission was fluctuated with two peaks (1996 and 2006), and total emission doubled from 15.4 Tg to 30.8 Tg, at an annual growth rate of 4.4% (6.3% since 2000). Due to the extensive application of FGD technology and the phase-out of small, high emitting units, the SO(2) emission began to decrease after 2006. Furthermore, the differences among estimates reported in literatures highlight a great need for further research to reduce the uncertainties with more detailed information on key sources and actual operation of devices. PMID:21851093

Su, Shenshen; Li, Bengang; Cui, Siyu; Tao, Shu

2011-10-01

350

Spatial Distribution of Ozone and Sulfur Dioxide on Ganymede and Europa  

NASA Astrophysics Data System (ADS)

The discovery of O_2 and O_3 in spectra of Ganymede's trailing hemisphere has revealed its icy surface to be an unexpectedly complex and dynamic environment. Europa, exposed to a slightly different radiation environment, has SO_2 on its trailing hemisphere with no trace of either O_3 or O_2. What role is played by plasma composition and energy, surface-ice composition, surface temperature, porosity, global magnetic field, or other possible physical parameters in determining whether oxygen or sulfur-bearing molecules, and how much, will be produced is unknown. Scant existing data on spatial distributions of these molecules suggests that the simplest model, abundance peaking at the antapex of orbital motion and decreasing symmetrically away from that point is inadequate. The new capability to measure spectra at 0.1 arcsec spatial scales offered by STIS gives us the opportunity to address such questions by mapping the distribution of O_3 and OH on Ganymede and SO_2 on Europa. In addition, STIS can obtain the first albedo spectra of these satellites at wavelengths below ~ 210 nm because STIS will not be sensitive to scattered visible light as was the FOS. Understanding the details of how the ice of Europa and Ganymede are chemically processed will help to determine whether ion-surface systems should be expected on other icy satellites outside the Jupiter system.

Noll, Keith

1997-12-01

351

Process for removing sulfur and sulfur compounds from the effluent of industrial processes  

Microsoft Academic Search

Sulfur dioxide in the stack gas from an industrial process is converted to elemental sulfur in a claus reactor at low temperature to produce sulfur fume. The sulfur is condensed by direct heat transfer with a continuously flowing countercurrent recirculating catalyst and a substantially sulfur dioxide-free gas is discharged. Catalyst and condensed sulfur are fed into the top of a

Sims

1981-01-01

352

Theoretical and experimental studies of the spin trapping of inorganic radicals by 5,5-dimethyl-1-pyrroline N-oxide (DMPO). 1. Carbon dioxide radical anion.  

PubMed

The carbon dioxide radical anion (CO2*-) is known to be generated in vivo through various chemical and biochemical pathways. Electron paramagnetic resonance (EPR) spin trapping with the commonly used spin trap, 5,5-dimethyl-1-pyrroline N-oxide (DMPO), has been employed in the detection of CO2*-. The thermodynamics of CO2*- addition to DMPO was predicted using density functional theory (DFT) at the B3LYP/6-31++G**//B3LYP/6-31G* and B3LYP/6-311+G* levels with the polarizable continuum model (PCM) to simulate the effect of the bulk dielectric effect of water on the calculated energetics. Three possible products of CO2*- addition to DMPO were predicted: (1) a carboxylate adduct, (2) pyrroline-alcohol and (3) DMPO-OH. Experimentally, UV photolysis of H2O2 in the presence of sodium formate (NaHCO2) and DMPO gave an EPR spectrum characteristic of a C-centered carboxylate adduct and is consistent with the theoretically derived hyperfine coupling constants (hfcc). The pKa of the carboxylate adduct was estimated computationally to be 6.4. The mode of CO2*- addition to DMPO is predicted to be governed predominantly by the spin (density) population on the radical, whereas electrostatic effects are not the dominant factor for the formation of the persistent adduct. The thermodynamic behavior of CO2*- in the aqueous phase is predicted to be similar to that of mercapto radical (*SH), indicating that formation of CO2*- in biological systems may have an important role in the initiation of oxidative damage in cells. PMID:17149843

Villamena, Frederick A; Locigno, Edward J; Rockenbauer, Antal; Hadad, Christopher M; Zweier, Jay L

2006-12-14

353

Selective Extraction of Metals from Pacific Sea Nodules with Dissolved Sulfur Dioxide  

NASA Astrophysics Data System (ADS)

How to tritrate a rock? … The following article illustrates the possibility of titrating a metallic constituent in a mineral with a selective reagent to an endpoint of near complete metal extraction. A very rapid and efficient—almost instantaneous and quantitative—method has been devised to differentially leach manganese, nickel, and cobalt to the exclusion of copper and iron from deep-sea nodules.1 In this method, a given weight of raw sea nodules ground to -200 mesh in an aqueous slurry is contacted for 10 min at room temperature and ambient pressure with a specified quantity of SO2. An independent leaching parameter R has been defined as the ratio of the number of moles of SO2 in the leaching solution to the weight of sea nodules. Variation of metal extraction with R generates sigmoidal curves characteristic of the metals extracted. A threshold value of R is required to initiate the leaching of a given metal from the mixed oxides. Once this threshold is reached, the metal recovery can rise above 95% in less than 10 minutes. For increasing value of R the extractability of various metals from Pacific sea nodules by SO2 follows the order: Mn > Ni > Co ? Fe, Al, Cu. Disparity in the R values permits a variety of selective leaching systems and metal separations simply by changing the quantity of SO2 in the contacting solution. Success in this leaching system depends on comminuting the nodules to less than 100 mesh. Above this critical size, leaching is slowed due to the inaccessibility of the inner particle reacting groups to the SO2 leaching agent, resulting in lower and nonselective extractions of preferred metal values. Leaching with HCl solutions of the same pH level as dissolved SO2 yielded mixed, slow, and incomplete metal extractions. This finding rules out any interpretation based on hydrogen ion from the ionization of sulfurous acid as the leaching agent. The leaching curves observed in the new system resemble the complexometric titration curves of heavy metals with specific coordination species.

Khalafalla, Sanaa E.; Pahlman, John E.

1981-08-01

354

Fundamental study of ammonia-sulfur dioxide reactions to form solid particles. Final report  

SciTech Connect

The effects of reaction residence time, presence of inert particles and moisture content on the SO{sub 2} removal and the product particle size distributions have been determined. Results indicated that both gas phase and particle phase reach equilibria in a very short time. The presence of inert particles increases the SO{sub 2} removal efficiency slightly, with a greater increase in removal efficiency at higher surface areas. Moisture content is the most important parameter affecting SO{sub 2} removal. Increasing the moisture content from 1.6% to 6.4% by volume results in a 30% increase of the SO{sub 2} removal at a reaction temperature of 51{degree}C. The products at near anhydrous conditions were concluded to be NH{sub 3}SO{sub 2}, (NH{sub 3}){sub 2}SO{sub 2} and (NH{sub 4}){sub 2}S{sub 2}O{sub 5}. While the products at humid conditions could be either the 1:1 sulfites, NH{sub 4}HSO{sub 3} and (NH{sub 4}){sub 2}S{sub 2}O{sub 5}, or the 2:1 sulfites, (NH{sub 4}){sub 2}SO{sub 3} and (NH{sub 4}){sub 2}SO{sub 3} {minus}H{sub 2}O, or a mixture of the 1:1 and 2:1 sulfite. Those sulfite particles could subsequently oxidize to form the more stable sulfate particles. A gas-to-particle formation model has been developed to simulate the NH{sub 3}-SO{sub 2} system in the presence and absence of seed aerosols at trace water conditions. This model accounts for simultaneous nucleation, coagulation, condensation and chemical reaction. The applicability of utilizing ammonia injection to a flue gas system has been discussed in terms of two possible removal schemes. One utilizes ammonia injection alone and the other is in conjunction with the injection of Ca(OH){sub 2} slurry in a spray dryer system. Both schemes have the potential of achieving over 90% SO{sub 2} removal from power plants burning high-sulfur coals.

Biswas, P.; Bai, H. [Cincinnati Univ., OH (United States). Dept. of Civil and Environmental Engineering

1994-01-18

355

Cell type specificity of female lung cancer associated with sulfur dioxide from air pollutants in Taiwan: An ecological study  

PubMed Central

Background Many studies have examined the association between air pollutants (including sulfur dioxide [SO2], carbon monoxide [CO], nitrogen dioxide [NO2], nitric oxide [NO], ozone [O3], and particulate matter < 10 ?m [PM10]) and lung cancer. However, data from previous studies on pathological cell types were limited, especially for SO2 exposure. We aimed to explore the association between SO2 exposure from outdoor air pollutants and female lung cancer incidence by cell type specificity. Methods We conducted an ecological study and calculated annual average concentration of 6 air pollutants (SO2, CO, NO2, NO, O3, and PM10) using data from Taiwan Environmental Protection Administration air quality monitoring stations. The Poisson regression models were used to evaluate the association between SO2 and age-standardized incidence rate of female lung cancer by two major pathological types (adenocarcinoma [AC] and squamous cell carcinoma [SCC]). In order to understand whether there is a dose-response relationship between SO2 and two major pathological types, we analyzed 4 levels of exposure based on quartiles of concentration of SO2. Results The Poisson regression results showed that with the first quartile of SO2 concentration as the baseline, the relative risks for AC/SCC type cancer among females were 1.20 (95% confidence interval [CI], 1.04-1.37)/1.39 (95% CI, 0.96-2.01) for the second, 1.22 (95% CI, 1.04-1.43)/1.58 (95% CI, 1.06-2.37) for the third, and 1.27 (95% CI, 1.06-1.52)/1.80 (95% CI, 1.15-2.84) for the fourth quartile of SO2 concentration. The tests for trend were statistically significant for both AC and SCC at P = 0.0272 and 0.0145, respectively. Conclusion The current study suggests that SO2 exposure as an air pollutant may increase female lung cancer incidence and the associations with female lung cancer is much stronger for SCC than for AC. The findings of this study warrant further investigation on the role of SO2 in the etiology of SCC.

2012-01-01

356

Theoretical studies of the marine sulfur cycle  

NASA Technical Reports Server (NTRS)

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

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

1985-01-01

357

Endogenous sulfur dioxide protects against isoproterenol-induced myocardial injury and increases myocardial antioxidant capacity in rats.  

PubMed

Recently, sulfur dioxide (SO(2)) was discovered to be produced in the cardiovascular system and to influence important biological processes. Here, we investigated changes in endogenous SO(2)/glutamic oxaloacetic transaminase (GOT) pathway in the development of isoproterenol (ISO)-induced myocardial injury in rats and the regulatory effect of SO(2) on cardiac function, myocardial micro- and ultrastructure, and oxidative stress. Wistar male rats were divided into control, ISO-treated, ISO+SO(2), and SO(2) groups. At the termination of the experiment, parameters of cardiac function and hemodynamics were measured and the micro- and ultrastructure of myocardium and stereological ultrastructure of mitochondria were analyzed. Myocardial SO(2) content was detected by high-performance liquid chromatography. GOT (key enzyme for endogenous SO(2) production) activity and gene (GOT1 and GOT2) expressions were measured, and superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), hydrogen peroxide, and superoxide radical levels were assayed. SOD (SOD1 and SOD2) and GSH-Px (GSH-Px1) gene expressions were also detected. The results showed that SO(2) donor at a dose of 85?mg/(kg?day) did not impact the cardiac function and structure of rats, but exerted a subtle influence on myocardial redox status. ISO-treated rats exhibited decreased cardiac function, damaged myocardial structures, and downregulated endogenous SO(2)/GOT pathway. Meanwhile, myocardial oxidative stress increased, whereas antioxidative capacity downregulated. Administration of SO(2) markedly improved cardiac function and ISO-induced myocardial damage by ameliorating the pathological structure of the myocardium and the mitochondria. At the same time, myocardial products of oxidative stress decreased, whereas antioxidative capacity increased. These results suggest that downregulation of the endogenous SO(2)/GOT pathway is likely involved in the pathogenesis of ISO-induced myocardial injury. SO(2) protects against ISO-induced myocardial injury associated with increased myocardial antioxidant capacity in rats. PMID:20733562

Liang, Yinfang; Liu, Die; Ochs, Todd; Tang, Chaoshu; Chen, Stella; Zhang, Suqing; Geng, Bin; Jin, Hongfang; Du, Junbao

2011-01-01

358

Risk of Asthmatic Episodes in Children Exposed to Sulfur Dioxide Stack Emissions from a Refinery Point Source in Montreal, Canada  

PubMed Central

Background Little is known about the respiratory effects of short-term exposures to petroleum refinery emissions in young children. This study is an extension of an ecologic study that found an increased rate of hospitalizations for respiratory conditions among children living near petroleum refineries in Montreal (Canada). Methods We used a time-stratified case–crossover design to assess the risk of asthma episodes in relation to short-term variations in sulfur dioxide levels among children 2–4 years of age living within 0.5–7.5 km of the refinery stacks. Health data used to measure asthma episodes included emergency department (ED) visits and hospital admissions from 1996 to 2004. We estimated daily levels of SO2 at the residence of children using a) two fixed-site SO2 monitors located near the refineries and b) the AERMOD (American Meteorological Society/Environmental Protection Agency Regulatory Model) atmospheric dispersion model. We used conditional logistic regression to estimate odds ratios associated with an increase in the interquartile range of daily SO2 mean and peak exposures (31.2 ppb for AERMOD peaks). We adjusted for temperature, relative humidity, and regional/urban background air pollutant levels. Results The risks of asthma ED visits and hospitalizations were more pronounced for same-day (lag 0) SO2 peak levels than for mean levels on the same day, or for other lags: the adjusted odds ratios estimated for same-day SO2 peak levels from AERMOD were 1.10 [95% confidence interval (CI), 1.00–1.22] and 1.42 (95% CI, 1.10–1.82), over the interquartile range, for ED visits and hospital admissions, respectively. Conclusions Short-term episodes of increased SO2 exposures from refinery stack emissions were associated with a higher number of asthma episodes in nearby children.

Smargiassi, Audrey; Kosatsky, Tom; Hicks, John; Plante, Celine; Armstrong, Ben; Villeneuve, Paul J.; Goudreau, Sophie

2009-01-01

359

Volcanic sulfur dioxide plume forecasts based on UV satellite retrievals for the 2011 Grímsvötn and the 2010 Eyjafjallajökull eruption  

NASA Astrophysics Data System (ADS)

sulfur dioxide plumes released by the eruptions of the Icelandic volcanoes Eyjafjallajökull in May 2010 and Grímsvötn in May 2011 were studied using satellite observations from the Second Global Ozone Monitoring Experiment (GOME-2), Ozone Monitoring Instrument (OMI), and Scanning Imaging Absorption Spectrometer for Atmospheric Chartography and modeled with the Integrated Forecasting System of the European Centre for Medium-Range Weather Forecasts (ECMWF). The retrievals of SO2 total columns (TCSO2) were (i) used to estimate emission rate and injection height of the two eruptions and (ii) assimilated with ECMWF's four-dimensional variational data assimilation algorithm to obtain initial conditions for subsequent forecasts. The OMI retrievals provided the highest plume observation values, and GOME-2 had the best coverage. The emission parameters were estimated by comparing TCSO2 observations with an ensemble of test tracers injected at different heights. The applied methodology led to emission estimates of 0.25 Tg over 20 days in May 2010 and 0.32 Tg over 2 days in May 2011. The SO2 analyses produced by assimilating GOME-2 TCSO2 retrievals captured the plume maxima well but exaggerated the plume area. The injection height estimate was used during the assimilation to determine the height of the assimilated plume. Plume forecasts were evaluated by means of hit-rate and plume-size statistics for different TCSO2 thresholds. Plume forecasts using either the emission parameters or the SO2 analyses as initial conditions agreed reasonably with the observations, but using both led to the best forecast performance. The initialization with SO2 analysis fields improved, in particular, the forecast of the Grímsvötn plume after the end of the eruption. The developed forecast and assimilation system can be applied for near-real-time forecasting of volcanic SO2 plumes.

Flemming, Johannes; Inness, Antje

2013-09-01

360

Pre-exposure to sulfur dioxide attenuates most allergic reactions upon trimellitic anhydride challenge in sensitized Brown Norway rats.  

PubMed

Irritant-induced inflammation of the airways may aggravate respiratory allergy induced by chemical respiratory allergens. Therefore, it was studied whether airway irritation by sulfur dioxide (SO(2)) would enhance respiratory allergic reactions to trimellitic anhydride (TMA), using a rat model. Brown Norway (BN) rats were topically sensitized, subsequently exposed for a single time or repeatedly to 300 ppm SO(2), and challenged by inhalation to a distinctly irritating or minimally irritating concentration of TMA after the (last) SO(2) exposure. Repeated exposure to SO(2) alone reduced breathing frequency during exposure, and caused epithelial alterations including hyperplasia and squamous metaplasia, and infiltration of polymorphonuclear inflammatory cells into nasal tissues, larynx, trachea, and bronchi/bronchioli. Histopathological changes were less prominent after 1 day of SO(2) exposure. Repeated pre-exposure to SO(2) reduced the number of TMA-induced apnoeas, in an SO(2) exposure duration-dependent manner. This effect of SO(2) on TMA-induced functional allergic reactions (apnoeas) was distinct only when the TMA challenge concentration was not too irritating itself. Repeated pre-exposure to SO(2) reduced TMA-induced laryngeal ulceration, goblet-cell hyperplasia, and inflammation in the lungs in most animals, regardless of the TMA challenge concentration. The SO(2)-induced replacement of normal respiratory epithelium by less sensitive, squamous epithelium may offer an explanation for the, unexpected, reduced allergic manifestation. However in a few animals, SO(2) appeared to facilitate TMA-induced irritation, probably due to incomplete protection. Overall, SO(2) exposure of TMA-sensitized rats reduced TMA-related allergic respiratory responses in most animals. PMID:20067440

Arts, Josje H E; Jacobs, Erik J; Kuper, C Frieke

2010-02-01

361

Land Use Regression Modeling To Estimate Historic (1962-1991) Concentrations of Black Smoke and Sulfur Dioxide for Great Britain  

PubMed Central

Land-use regression modeling was used to develop maps of annual average black smoke (BS) and sulfur dioxide (SO2) concentrations in 1962, 1971, 1981, and 1991 for Great Britain on a 1 km grid for use in epidemiological studies. Models were developed in a GIS using data on land cover, the road network, and population, summarized within circular buffers around air pollution monitoring sites, together with altitude and coordinates of monitoring sites to consider global trend surfaces. Models were developed against the log-normal (LN) concentration, yielding R2 values of 0.68 (n = 534), 0.68 (n = 767), 0.41 (n = 771), and 0.39 (n = 155) for BS and 0.61 (n = 482), 0.65 (n = 733), 0.38 (n = 756), and 0.24 (n = 153) for SO2 in 1962, 1971, 1981, and 1991, respectively. Model evaluation was undertaken using concentrations at an independent set of monitoring sites. For BS, values of R2 were 0.56 (n = 133), 0.41 (n = 191), 0.38 (n = 193), and 0.34 (n = 37), and for SO2 values of R2 were 0.71 (n = 121), 0.57 (n = 183), 0.26 (n = 189), and 0.31 (n = 38) for 1962, 1971, 1981, and 1991, respectively. Models slightly underpredicted (fractional bias: 0??0.1) monitored concentrations of both pollutants for all years. This is the first study to produce historic concentration maps at a national level going back to the 1960s.

2011-01-01

362

Kinetics of oxidation of carbon in liquid iron-carbon-silicon-manganese-sulfur alloys by carbon dioxide in nitrogen  

NASA Astrophysics Data System (ADS)

The oxidation of carbon with the simultaneous oxidation of silicon, manganese, and iron of liquid alloys by carbon dioxide in nitrogen and the absorption of oxygen by the alloys from the gas were studied using 1-g liquid iron droplets levitated in a stream of the gas at 1575 °C to 1715 °C. Oxidation of carbon was favored over oxidation of silicon and manganese when cast iron (3.35 pct C, 2.0 pct Si, 0.36 pct Mn, and 0.05 pct S) reacted with CO2/N2 gas at 1635 °C. An increase in the flow rate of CO2/N2 gas increased the decarburization rate of cast iron. The rate of carbon oxidation by this gas mixture was found to be independent of temperature and alloying element concentrations (in the range of silicon = 0 to 2.0 pct manganese = 0 to 0.36 pct and sulfur = 0 to 0.5 pct) within the temperature range of the present study. Based on the results of a kinetic analysis, diffusion of CO2 in the boundary layer of the gas phase was found to be the rate-limiting step for the reactions during the earlier period of the reaction when the contents of carbon, silicon, and manganese are higher. However, the limiting step changed to diffusion of the elements in the metal phase during the middle period of the reaction and then to the diffusion of CO in the gas phase during the later period of the reaction when the content of the elements in the metal were relatively low. For the simultaneous oxidation reactions of several elements in the metal, however, the diffusion of CO2 in the gas phase is the primary limiting step of the reaction rate for the oxidation of carbon during the later period of reaction.

Sun, Haiping; Pehlke, Robert D.

1995-04-01

363

N2-, O2- and He-collision-induced broadening of sulfur dioxide ro-vibrational lines in the 9.2 ?m atmospheric window.  

PubMed

Sulfur dioxide (SO2) is a molecule of considerable interest for both atmospheric chemistry and astrophysics. In the Earth's atmosphere, it enters in the sulfur cycle and it is ubiquitous present in polluted atmospheres, where it is responsible for acid rains. It is also of astrophysical and planetological importance, being present on Venus and in interstellar clouds. In this work the collisional broadening of a number of ?1 ro-vibrational lines of SO2 perturbed by N2, O2 and He are investigated at room temperature in the 9 ?m atmospheric region by means of high resolution tunable diode laser (TDL) infrared spectroscopy. From N2- and O2-broadening coefficients, the broadening parameters of sulfur dioxide in air, useful for atmospheric applications, are derived as well. From the present measurements some conclusions on the quantum number dependence of the N2-, O2- and He-broadening coefficients are drawn. While the J dependence is weak for all the perturbers investigated, different trends with Ka are reported. N2-broadening coefficients show a slight decrease with increasing values of Ka, whereas O2 and He broadening cross sections first increase up to Ka(?)?6 and then they keep a nearly constant value. A comparison and a brief discussion on the efficiency of self-, N2-, O2- and He-collisional dynamics are given. The data obtained represent a significant analysis on foreign broadening of SO2 useful for atmospheric remote sensing and astrophysical applications. PMID:24060483

Tasinato, Nicola; Pietropolli Charmet, Andrea; Stoppa, Paolo; Giorgianni, Santi; Buffa, Giovanni

2014-01-24

364

Impact of free calcium oxide content of fly ash on dust and sulfur dioxide emissions in a lignite-fired power plant  

SciTech Connect

Emitted pollutants from the Agios Dimitrios lignite-fired power plant in northern Greece show a very strong linear correlation with the free calcium oxide content of the lignite ash. Dust (fly ash) emissions are positively correlated to free calcium oxide content, whereas sulfur dioxide (SO{sub 2}) emissions are negatively correlated. As a result, at present, the Agios Dimitrios Power Plant operates very strictly within the legislative limits on atmospheric particulate emission. In the study reported, the factors to be considered in assessing the impact of lignite combustion on the environment are presented and evaluated statistically. The ash appears to have a remarkable SO{sub 2} natural dry scrubbing capability when the free calcium oxide content ranges between 4 and 7%. Precipitator operating problems attributable to high ash resistivity can be overcome by injecting sulfur trioxide to reduce the ash resistivity, with, of course, a probable increase in operating costs. 27 refs., 7 figs., 1 tab.

Dimitrios Sotiropoulos; Andreas Georgakopoulos; Nestoras Kolovos [Agios Dimitrios Power Plant, Ptolemais (Greece). Public Power Corporation of Greece

2005-07-01

365

Electrochemical studies of the corrosion behavior of carbon and weathering steels in alternating wet/dry environments with sulfur dioxide gas  

SciTech Connect

Electrochemical impedance techniques were used to investigate the corrosion behavior of carbon steel (CS) and weathering steel (WS) in sulfur dioxide (SO{sub 2})-containing environments. Impedance measurements were conducted in a modified three-electrode electrochemical cell covered by a thin electrolyte layer during the wet/dry period. Results showed WS was more resistant to SO{sub 2}-induced atmospheric corrosion than CS. Three forms of impedance spectra were observed, depending upon exposure period. Accordingly, three impedance models were proposed to explain the characteristic impedance data and corrosion behaviors in different stages of exposure. The proposed models and equivalent circuits produced good agreement with experimental impedance data.

Wang, J.H.; Shih, H.C. [National Tsing Hua Univ., Hsinchu (Taiwan, Province of China). Dept. of Materials Science and Engineering; Wei, F.I. [China Steel Corp., Kaoshiung (Taiwan, Province of China)

1996-08-01

366

MAP3S/RAINE modeling abstracts, 1980. [Concise descriptions of models and availability for calculation of airborne concentration of sulfur dioxide and sulfate  

SciTech Connect

The MultiState Atmospheric Power Production Pollution Study (MAP3S) has produced as a primary research output a number of numerical models for the calculation of airborne concentrations of sulfur dioxide and sulfate resulting from anthropogenic sources. Concise descriptions of these models, and of related modeling developments, are collected in this report. For each model, or model component, there is included a listing of the authors, a summary of what it is the model calculates and the method used, a list of references, and a statement of availability.

Michael, P. (ed.) [ed.

1980-07-01

367

Total fluxes of sulfur dioxide from the Italian volcanoes Etna, Stromboli, and Vulcano measured by differential absorption lidar and passive differential optical absorption spectroscopy  

SciTech Connect

The authors present measurements of the total flux of sulfur dioxide from three Italian volcanoes Etna, Stromboli, and Vulcano, measured in a three day period in Sept, 1992. The fluxes were measured from shipboard by means of an active differential absorption lidar technique, and a passive differential optical absorption spectroscopy technique. Corrections had to be applied to the passive optical technique because the light source paths were not well defined. The total fluxes were found to be roughly 25, 180, and 1300 tons/day for Vulcano, Stromboli, and Etna, respectively. 43 refs., 10 figs., 6 tabs.

Edner, H.; Ragnarson, P.; Svanberg, S.; Wallinder, E. [Lund Institute of Technology (Sweden)] [Lund Institute of Technology (Sweden); Ferrara, R. [Istituto di Biofisica, Pisa (Italy)] [Istituto di Biofisica, Pisa (Italy); Cioni, R.; Raco, B.; Taddeucci, G. [Istituto di Geocronologia e Geochimica Isotopica, Pisa (Italy)] [Istituto di Geocronologia e Geochimica Isotopica, Pisa (Italy)

1994-09-20

368

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

369

A compilation of sulfur dioxide and carbon dioxide emission-rate data from Cook Inlet volcanoes (Redoubt, Spurr, Iliamna, and Augustine), Alaska during the period from 1990 to 1994  

USGS Publications Warehouse

Airborne sulfur dioxide (SO2) gas sampling of the Cook Inlet volcanoes (Mt. Spurr, Redoubt, Iliamna, and Augustine) began in 1986 when several measurements were carried out at Augustine volcano during the eruption of 1986 (Rose and others, 1988). More systematic monitoring for SO2 began in March 1990 and for carbon dioxide (CO2) began in June, 1990 at Redoubt Volcano (Brantley, 1990 and Casadevall and others, 1994) and continues to the present. This report contains all of the available daily SO2 and CO2 emission rates determined by the U.S. Geological Survey (USGS) from March 1990 through July 1994. Intermittent measurements (four to six month intervals) at Augustine and Iliamna began in 1990 and continues to the present. Intermittent measurements began at Mt. Spurr volcano in 1991, and were continued at more regular intervals from June, 1992 through the 1992 eruption at the Crater Peak vent to the present.

Doukas, Michael P.

1995-01-01

370

Characterization and identification of genes essential for dimethyl sulfide utilization in Pseudomonas putida strain DS1  

Microsoft Academic Search

Microbial dimethyl sulfide (DMS) conversion is thought to be involved in the global sulfur cycle. We isolated Pseudomonas putida strain DS1 from soil as a bacterium utilizing DMS as a sole sulfur source, and tried to elucidate the DMS conversion mechanism of strain DS1 at biochemical and genetic level. Strain DS1 oxidized DMS to dimethyl sulfone (DMSO 2) via dimethyl

T. Endoh; K. Kasuga; M. Horinouchi; T. Yoshida; H. Habe; H. Nojiri; T. Omori

2003-01-01

371

Determination of the effects of sulfur dioxide on recovery systems for CO/sub 2/. Final report, 1977-1980  

SciTech Connect

The present study was initiated to investigate the problems associated with recovery of CO/sub 2/ from flue gases for enhanced oil recovery. In particular, the scope of this work may be stated: determine the type of impurities formed in ammonia, monoethanolamine (MEA), and potassium carbonate systems when extracting CO/sub 2/ from oxidizing flue gases containing nitrogen oxides and sulfur oxides; determine the levels of impurity build-up in the solvents; estimate the impurity level in the recovered CO/sub 2/; evaluate the effect on corrosion in metals by these solvents in a flue gas environment; determine the carbon-dioxide absorption coefficients in solvents contaminated due to the pollutants present in the flue gas; evaluate the effect of particulate matter on absorption coefficients in the solvents; and recommend potential absorption systems for CO/sub 2/ from flue gas and estimate the cost of recovery. The results of this study indicate that in ammonia, ammonia sulfate is quickly formed to render that portion of the absorbent inactive. In MEA, amine sulfite and amine sulfate are the dominant impurities formed. In amine-activated potassium carbonate solutions, only sulfite and sulfate ions were found. No nitrogen-oxide species were found in any solution. The impurity levels obtained in the present experiments indicated no limit on contaminant build-up. The impurity level in the recovered CO/sub 2/ was estimated to be less than or equal to 100 ppM non-condensible gases, 20 to 200 ppM SO/sub 2/, and < 20 ppM NO/sub x. Corrosion in the absorption systems will be similar to that observed in CO/sub 2/ absorption systems from reducing gas streams. The absorption rate of CO/sub 2/ in solutions decreases with increasing loading of CO/sub 2/ in almost a linear fashion. Several alternative absorption systems were evaluated in a preliminary cost evaluation, and a K/sub 2/CO/sub 3/ (EAE activated) solution was recommended.

Sears, J.T.

1981-01-01

372

Gas-liquid interactions of ammonia, sulfur dioxide, hydrogen sulfide, deuterated acetic acid and ethanol on aqueous surfaces  

NASA Astrophysics Data System (ADS)

Heterogeneous gas-liquid interactions play a fundamental role in atmospheric chemistry and are of importance also in biochemical and industrial processes. Here we examine the gas-liquid interactions of several species important in the chemistry of the atmosphere. The experiments are performed using a droplet apparatus in which a stream of well-defined, monodisperse droplets is passed through a low pressure flow tube containing the gas phase species of interest. The uptake of gas species by the droplets is determined by measuring changes in gas density as the droplet area is changed in a step-wise fashion. The experimental results yield information useful in atmospheric modeling and important to the understanding of chemical interactions at the gas-liquid interface. The following studies were performed: (1) Uptake of gas phase ammonia (NH3) by aqueous surfaces was measured as a function of pH (0-13), temperature (263-293K), and gas liquid interaction time (2-15 ms). Uptake measurements yielded values of the mass accommodation and Henry's law coefficients as a function of temperature. (2) Uptake of gas phase sulfur dioxide (SO2) by aqueous surfaces was measured as a function of pH (3-14) and temperature (263-293K). Experimental results yielded the rate coefficient for the SO2 + OH- reaction and mass accommodation coefficient, both as a function of temperature. (3) Uptake of gas phase hydrogen sulfide (H2S) by aqueous surfaces was measured as a function of pH (10-14) and temperature. Studies yielded the rate coefficient for the reaction of H2S with OH- including the activation energy for the reaction. (4) Isotope exchange for deuterated gas-phase acetic acid and ethanol in contact with water (H 2O) droplets was studied using the droplet apparatus. Studies were conducted as a function of pH, droplet temperature and gas liquid interaction time. Experimental results provided a better understanding of the fundamental properties of the gas-liquid interface including the nature of the reactive processes at the gas-liquid interface.

Shi, Quan

1998-11-01

373

Methods of measuring sulfur dioxide, dustfall and suspended matter in city air, and their use in the study of air pollution in Italy*  

PubMed Central

This paper presents a comparative survey of the methods and apparatus used in Italy, particularly in Genoa, for measuring the three main components of city air pollution—sulfur dioxide, dustfall and suspended matter. The most frequently employed devices for sampling sulfur dioxide are the lead-peroxide and volumetric apparatuses, as developed by the British Department of Scientific and Industrial Research. For the collection of dustfall, the British standard deposit gauge is widely used; in Genoa, a simple, low-cost type of dustfall collector has been tried in combination with that gauge, and good results have been obtained. The measurement of suspended matter is effected by the thermal precipitator, electrostatic precipitator and konimeters of different types, in addition to the classic method of filtration through various media. In Genoa, suspended matter is monitored by automatic filter-paper samplers and directional samplers. The use of membrane filters for counting dust particles has proved particularly satisfactory. All these techniques are described in detail, and their results are subjected to statistical analysis.

Petrilli, F. L.

1962-01-01

374

Dimethyl Fumarate  

MedlinePLUS

... to treat psoriasis (a skin disease in which red, scaly patches form on some areas of the ... or any of the ingredients in dimethyl fumarate capsules. Ask your pharmacist or check the manufacturer's patient ...

375

Sulfur rate control system  

SciTech Connect

A sulfur rate control system is described for substantially optimizing particulate removal performance of an electrostatic precipitator in fluid communication with a flue carrying combustion products of a fossil fuel, comprising: an electrostatic precipitator having an inlet for receiving a flue gas: means for injecting sulfur trioxide into a flue for mixing with said flue gas at a location preceding entry of said flue gas into said electrostatic precipitator, said injection of sulfur trioxide being varied responsive to a proportional control signal; and, control means coupled to both said flue and said sulfur trioxide injection means for generating said proportional control signal, said control means including (1) means for measuring a sulfur dioxide concentration quantity in said flue gas at a location preceding said sulfur trioxide injection means, (2) means for measuring a flow rate of particulates in said flue gas at a location preceding said sulfur trioxide injection means, and (3) a controller for calculating a ratio between said sulfur dioxide concentration quantity and said flow rate of particulates, said ratio calculating controller having a first input coupled to said sulfur dioxide measuring means and a second input coupled to said particulate flow rate measuring means for generating said proportional control signal in proportion to a difference between a predetermined value and said ratio between said sulfur dioxide concentration quantity and said flow rate of particulates, said ratio controller having an output coupled to said sulfur trioxide injection means for maximizing particulate removal efficiency of said electrostatic precipitator.

Bell, T.A.; Mullendore, M.G.; Kleinfeldt, T.E.; Walker, H.G. Jr.

1993-07-20

376

Carbon dioxide conversion to dimethyl carbonate: The effect of silica as support for SnO 2 and ZrO 2 catalysts  

Microsoft Academic Search

Abundant in nature, CO2 poses few health hazards and consequently is a promising alternative to phosgene feedstock according with the principles of Green Chemistry and Engineering. The synthesis organic carbonates from CO2 instead of phosgene is highly challenging as CO2 is much less reactive. As part of our ongoing research on the investigation of catalysts for dimethyl carbonate (DMC) synthesis

Danielle Ballivet-Tkatchenko; João H. Z. dos Santos; Karine Philippot; Sivakumar Vasireddy

2011-01-01

377

Sulfur X-Ray Absorption And Vibrational Spectroscopic Study of Sulfur Dioxide, Sulfite, And Sulfonate Solutions And of the Substituted Sulfonate Ions X(3)CSO(3-)(X = H, Cl, F)  

SciTech Connect

Sulfur K-edge X-ray absorption near-edge structure (XANES) spectra have been recorded and the S(1s) electron excitations evaluated by means of density functional theory-transition potential (DFT-TP) calculations to provide insight into the coordination, bonding, and electronic structure. The XANES spectra for the various species in sulfur dioxide and aqueous sodium sulfite solutions show considerable differences at different pH values in the environmentally important sulfite(IV) system. In strongly acidic (pH < {approx}1) aqueous sulfite solution the XANES spectra confirm that the hydrated sulfur dioxide molecule, SO{sub 2}(aq), dominates. The theoretical spectra are consistent with an OSO angle of {approx}119{sup o} in gas phase and acetonitrile solution, while in aqueous solution hydrogen bonding reduces the angle to {approx}116{sup o}. The hydration affects the XANES spectra also for the sulfite ion, SO{sub 3}{sup 2-}. At intermediate pH (4) the two coordination isomers, the sulfonate (HSO{sub 3{sup -}}) and hydrogen sulfite (SO{sub 3}H{sup -}) ions with the hydrogen atom coordinated to sulfur and oxygen, respectively, could be distinguished with the ratio HSO{sub 3{sup -}}:SO{sub 3}H{sup -} about 0.28:0.72 at 298 K. The relative amount of HSO{sub 3{sup -}} increased with increasing temperature in the investigated range from 275 to 343 K. XANES spectra of sulfonate, methanesulfonate, trichloromethanesulfonate, and trifluoromethanesulfonate compounds, all with closely similar S-O bond distances in tetrahedral configuration around the sulfur atom, were interpreted by DFT-TP computations. The energy of their main electronic transition from the sulfur K-shell is about 2478 eV. The additional absorption features are similar when a hydrogen atom or an electron-donating methyl group is bonded to the -SO{sub 3} group. Significant changes occur for the electronegative trichloromethyl (Cl{sub 3}C-) and trifluoromethyl (F{sub 3}C-) groups, which strongly affect the distribution especially of the {pi} electrons around the sulfur atom. The S-D bond distance 1.38(2) {angstrom} was obtained for the deuterated sulfonate (DSO{sub 3{sup -}}) ion by Rietveld analysis of neutron powder diffraction data of CsDSO{sub 3}. Raman and infrared absorption spectra of the CsHSO{sub 3}, CsDSO{sub 3}, H{sub 3}CSO{sub 3}Na, and Cl{sub 3}CSO{sub 3}Na{center_dot}H{sub 2}O compounds and Raman spectra of the sulfite solutions have been interpreted by normal coordinate calculations. The C-S stretching force constant for the trichloromethanesulfonate ion obtains an anomalously low value due to steric repulsion between the Cl{sub 3}C- and -SO{sub 3} groups. The S-O stretching force constants were correlated with corresponding S-O bond distances for several oxosulfur species.

Risberg, E.Damian; Eriksson, L.; Mink, J.; Pettersson, L.G.M.; Skripkin, M.Yu.; Sandstrom, M.

2009-06-02

378

Chemical Recycling of Carbon Dioxide to Methanol and Dimethyl Ether: From Greenhouse Gas to Renewable, Environmentally Carbon Neutral Fuels and Synthetic Hydrocarbons  

Microsoft Academic Search

Nature's photosynthesis uses the sun's energy with chlorophyll in plants as a catalyst to recycle carbon dioxide and water into new plant life. Only given sufficient geological time can new fossil fuels be formed naturally. In contrast, chemical recycling of carbon dioxide from natural and industrial sources as well as varied human activities or even from the air itself to

George A. Olah; Alain Goeppert; G. K. Surya Prakash

2009-01-01

379

Determination of sulfur forms in wine including free and total sulfur dioxide based on molecular absorption of carbon monosulfide in the air-acetylene flame.  

PubMed

A new method for the determination of sulfur forms in wine, i.e., free SO(2), total SO(2), bound SO(2), total S, and sulfate, is presented. The method is based on the measurement of the carbon monosulfide (CS) molecular absorption produced in a conventional air-acetylene flame using high-resolution continuum source absorption spectrometry. Individual sulfur forms can be distinguished because of the different sensitivities of the corresponding CS molecular absorption. The sensitivity of free SO(2) is about three times higher than the value for bound SO(2) and sulfate. The method makes use of procedures similar to those used in classic reference methods. Its performance is verified by analyzing six wine samples. Relative standard deviations are between 5 and 13% for free SO(2) and between 1 and 3% for total SO(2). For the validation of the accuracy of the new method, the results are compared with those of reference methods. The agreement of the values for total SO(2) with values of the classic method is satisfactory: five out of six samples show deviations less than 16%. Due to the instability of free SO(2) in wine and the known problems of the used reference method, serious deviations of the free SO(2) results are found for three samples. The evaluation of the limits of detection focuses on the value for free SO(2), which is the sulfur form having by far the lowest concentration in wine. Here, the achievable limit of detection is 1.8 mg L(-1). [figure: see text] Detection of non-metal elements using continuum source flame absorption spectrometry. PMID:17972067

Huang, Mao Dong; Becker-Ross, Helmut; Florek, Stefan; Heitmann, Uwe; Okruss, Michael; Patz, Claus-Dieter

2008-01-01

380

Correct Assembly of Iron-Sulfur Cluster FS0 into Escherichia coli Dimethyl Sulfoxide Reductase (DmsABC) Is a Prerequisite for Molybdenum Cofactor Insertion*  

PubMed Central

The FS0 [4Fe-4S] cluster of the catalytic subunit (DmsA) of Escherichia coli dimethyl sulfoxide reductase (DmsABC) plays a key role in the electron transfer relay. We have now established an additional role for the cluster in directing molybdenum cofactor assembly during enzyme maturation. EPR spectroscopy indicates that FS0 has a high spin ground state (S = 32) in its reduced form, resulting in an EPR spectrum with a peak at g ? 5.0. The cluster is predicted to be in close proximity to the molybdo-bis(pyranopterin guanine dinucleotide) (Mo-bisPGD) cofactor, which provides the site of dimethyl sulfoxide reduction. Comparison with nitrate reductase A (NarGHI) indicates that a sequence of residues (18CTVNC22) plays a role in both FS0 and Mo-bisPGD coordination. A DmsA?N21 mutant prevented Mo-bisPGD binding and resulted in a degenerate [3Fe-4S] cluster form of FS0 being assembled. DmsA belongs to the Type II subclass of Mo-bisPGD-containing catalytic subunits that is distinguished from the Type I subclass by having three rather than two residues between the first two Cys residues coordinating FS0 and a conserved Arg residue rather than a Lys residue following the fourth cluster coordinating Cys. We introduced a Type I Cys group into DmsA in two stages. We changed its sequence from 18CATVNCBGSRCCP27 to 18CATYCBGVGCCG26 (similar to that of formate dehydrogenase (FdnG)) and demonstrated that this eliminated both Mo-bisPGD binding and EPR-detectable FS0. We then combined this change with a DmsAR61K mutation and demonstrated that this additional change partially rescued Mo-bisPGD insertion.

Tang, Huipo; Rothery, Richard A.; Voss, James E.; Weiner, Joel H.

2011-01-01

381

Correct assembly of iron-sulfur cluster FS0 into Escherichia coli dimethyl sulfoxide reductase (DmsABC) is a prerequisite for molybdenum cofactor insertion.  

PubMed

The FS0 [4Fe-4S] cluster of the catalytic subunit (DmsA) of Escherichia coli dimethyl sulfoxide reductase (DmsABC) plays a key role in the electron transfer relay. We have now established an additional role for the cluster in directing molybdenum cofactor assembly during enzyme maturation. EPR spectroscopy indicates that FS0 has a high spin ground state (S = 3/2) in its reduced form, resulting in an EPR spectrum with a peak at g ? 5.0. The cluster is predicted to be in close proximity to the molybdo-bis(pyranopterin guanine dinucleotide) (Mo-bisPGD) cofactor, which provides the site of dimethyl sulfoxide reduction. Comparison with nitrate reductase A (NarGHI) indicates that a sequence of residues ((18)CTVNC(22)) plays a role in both FS0 and Mo-bisPGD coordination. A DmsA(?N21) mutant prevented Mo-bisPGD binding and resulted in a degenerate [3Fe-4S] cluster form of FS0 being assembled. DmsA belongs to the Type II subclass of Mo-bisPGD-containing catalytic subunits that is distinguished from the Type I subclass by having three rather than two residues between the first two Cys residues coordinating FS0 and a conserved Arg residue rather than a Lys residue following the fourth cluster coordinating Cys. We introduced a Type I Cys group into DmsA in two stages. We changed its sequence from (18)C(A)TVNC(B)GSRC(C)P(27) to (18)C(A)TYC(B)GVGC(C)G(26) (similar to that of formate dehydrogenase (FdnG)) and demonstrated that this eliminated both Mo-bisPGD binding and EPR-detectable FS0. We then combined this change with a DmsA(R61K) mutation and demonstrated that this additional change partially rescued Mo-bisPGD insertion. PMID:21357619

Tang, Huipo; Rothery, Richard A; Voss, James E; Weiner, Joel H

2011-04-29

382

Interaction of mineral dust with gas phase nitric acid and sulfur dioxide during the MINATROC II field campaign: First estimate of the uptake coefficient ?HNO3 from atmospheric data  

Microsoft Academic Search

Mineral dust, one of the most abundant aerosols by mass in the atmosphere, may have a lasting but to date almost unexplored effect on the trace gases nitric acid (HNO3) and sulfur dioxide (SO2). These gases have an important influence on, for example, the tropospheric ozone cycle, aerosol formation or acid rain. Within the second part of the MINATROC project

B. Umann; F. Arnold; C. Schaal; M. Hanke; J. Uecker; H. Aufmhoff; Y. Balkanski; R. Van Dingenen

2005-01-01

383

Quaternary Ammonium Ionic Liquids as Bifunctional Catalysts for One-step Synthesis of Dimethyl Carbonate from Ethylene Oxide, Carbon Dioxide and Methanol  

Microsoft Academic Search

\\u000a Abstract  One kind of novel ionic liquids (ILs) with a tertiary amino moiety and a quaternary ammonium group were synthesized and identified\\u000a by FT-IR, 1H and 13C NMR. The elemental chemical state and basicity of ILs were determined by XPS and Hammett indicator method, respectively.\\u000a Then the catalytic performance of these bi-functional catalysts was investigated in one-step synthesis of dimethyl carbonate

Jian Li; Liguo Wang; Feng Shi; Shimin Liu; Yude He; Liujin Lu; Xiangyuan Ma; Youquan Deng

2011-01-01

384

Potential particulate pollution derived from UV-induced degradation of odorous dimethyl sulfide.  

PubMed

UV-induced degradation of odorous dimethyl sulfide (DMS) was carried out in a static White cell chamber with UV irradiation. The combination of in situ Fourier transform infrared (FT-IR) spectrometer, gas chromatograph-mass spectrometer (GC-MS), wide-range particle spectrometer (WPS) technique, filter sampling and ion chromatographic (IC) analysis was used to monitor the gaseous and potential particulate products. During 240 min of UV irradiation, the degradation efficiency of DMS attained 20.9%, and partially oxidized sulfur-containing gaseous products, such as sulfur dioxide (SO2), carbonyl sulfide (OCS), dimethyl sulfoxide (DMSO), dimethyl sulfone (DMSO2) and dimethyl disulfide (DMDS) were identified by in situ FT-IR and GC-MS analysis, respectively. Accompanying with the oxidation of DMS, suspended particles were directly detected to be formed by WPS techniques. These particles were measured mainly in the size range of accumulation mode, and increased their count median diameter throughout the whole removal process. IC analysis of the filter samples revealed that methanesulfonic acid (MSA), sulfuric acid (H2SO4) and other unidentified chemicals accounted for the major non-refractory compositions of these particles. Based on products analysis and possible intermediates formed, the degradation pathways of DMS were proposed as the combination of the O(1D)- and the OH- initiated oxidation mechanisms. A plausible formation mechanism of the suspended particles was also analyzed. It is concluded that UV-induced degradation of odorous DMS is potentially a source of particulate pollutants in the atmosphere. PMID:21476340

Qiao, Liping; Chen, Jianmin; Yang, Xin

2011-01-01

385

Total sulfur dioxide emissions and pre-eruption vapor-saturated magma at Mount St. Helens, 1980-88  

SciTech Connect

SO{sub 2} from explosive volcanism can cause significant climatic and atmospheric impacts, but the source of the sulfur is controversial. TOMS, COSPEC, and ash leachate data for Mount St. Helens from the time of the climactic eruption on 18 May 1980 to the final stages of non-explosive degassing in 1988 give a total SO{sub 2} emission of 2 Mt. COSPEC data show a sharp drop in emission rate that was apparently controlled by a decreasing rate of magma supply. A total SO{sub 2} emission of only 0.08 Mt is estimated from melt inclusion data and the conventional assumption that the main sulfur source was pre-eruption melt; commonly invoked sources of {open_quotes}excess sulfur{close_quotes} (anhydrite decomposition, basaltic magma, and degassing of non-erupted magma) are unlikely in this case. Thus melt inclusions may significantly underestimate SO{sub 2} emissions and impacts of explosive volcanism on climate and the atmosphere. Measured CO{sub 2} emissions, together with the H{sub 2}O content of melt inclusions and experimental solubility data, indicate the Mount St. Helens dacite was vapor-saturated at depth prior to ascent and suggest that a vapor phase was the main source of sulfur for the 2-Mt of SO{sub 2}. A vapor source is consistent with experimental studies on the Mount St. Helens dacite and removes the need for a much debated shallow magma body. 23 refs., 3 figs.

Gerlach, T.M.; McGee, K.A. [Geological Survey, Vancouver, WA (United States)] [Geological Survey, Vancouver, WA (United States)

1994-12-15

386

The Radiolysis of Sulfur Dioxide and Hydrogen Sulfide in Water Ice: Implications for the Icy Jovian Satellites  

NASA Astrophysics Data System (ADS)

Spectra of Europa, Ganymede, and Callisto reveal surfaces dominated by frozen water (Calvin et al., 1995), hydrated materials (McCord et al., 1998b; Carlson et al., 1999), and minor amounts of SO2 (Lane et al., 1981; Noll et al., 1995), CO2 (Smythe et al., 1998), and H2O2 (Carlson et al., 1999). These icy moons undergo significant bombardment by jovian magnetospheric radiation (protons, electrons, and sulfur and oxygen ions) which alters their surface compositions. In order to understand these radiation-induced changes, we have measured the mid-infrared (IR) spectra of proton-irradiated H2O-ice mixtures containing SO2 or H2S. Samples with H2O/SO2 or H2O/H2S ratios of 3 and 30 have been irradiated at 86 K, 110 K, and 132 K, and the radiation half-lives of SO2 and H2S have been determined. New radiation products include H2S2, and ions (SO42- and HSO4-). During warming, we have identified the IR spectrum of both the tetrahydrate and monohydrate of sulfuric acid. In addition we have documented the dehydration of the monohydrate to form sulfuric acid near 250 K. A summary of these findings will be presented along with implications of similar processes affecting the outer icy shells of Europa, Ganymede, and Callisto. 691.gsfc.nasa.gov/cosmic.ice.lab

Moore, M. H.; Hudson, R. L.; Carlson, R. L.

2006-05-01

387

Dimethyl Disulfide Produced by the Naturally Associated Bacterium Bacillus sp B55 Promotes Nicotiana attenuata Growth by Enhancing Sulfur Nutrition[W  

PubMed Central

Bacillus sp B55, a bacterium naturally associated with Nicotiana attenuata roots, promotes growth and survival of wild-type and, particularly, ethylene (ET)–insensitive 35S-ethylene response1 (etr1) N. attenuata plants, which heterologously express the mutant Arabidopsis thaliana receptor ETR1-1. We found that the volatile organic compound (VOC) blend emitted by B55 promotes seedling growth, which is dominated by the S-containing compound dimethyl disulfide (DMDS). DMDS was depleted from the headspace during cocultivation with seedlings in bipartite Petri dishes, and 35S was assimilated from the bacterial VOC bouquet and incorporated into plant proteins. In wild-type and 35S-etr1 seedlings grown under different sulfate (SO4?2) supply conditions, exposure to synthetic DMDS led to genotype-dependent plant growth promotion effects. For the wild type, only S-starved seedlings benefited from DMDS exposure. By contrast, growth of 35S-etr1 seedlings, which we demonstrate to have an unregulated S metabolism, increased at all SO4?2 supply rates. Exposure to B55 VOCs and DMDS rescued many of the growth phenotypes exhibited by ET-insensitive plants, including the lack of root hairs, poor lateral root growth, and low chlorophyll content. DMDS supplementation significantly reduced the expression of S assimilation genes, as well as Met biosynthesis and recycling. We conclude that DMDS by B55 production is a plant growth promotion mechanism that likely enhances the availability of reduced S, which is particularly beneficial for wild-type plants growing in S-deficient soils and for 35S-etr1 plants due to their impaired S uptake/assimilation/metabolism.

Meldau, Dorothea G.; Meldau, Stefan; Hoang, Long H.; Underberg, Stefanie; Wunsche, Hendrik; Baldwin, Ian T.

2013-01-01

388

Microporous Activated Carbons Prepared from Palm Shell by Thermal Activation and Their Application to Sulfur Dioxide Adsorption  

Microsoft Academic Search

Textural characterization of activated carbons prepared from palm shell by thermal activation with carbon dioxide (CO2) gas is reported in this paper. Palm shell (endocarp) is an abundant agricultural solid waste from palm-oil processing mills in many tropical countries such as Malaysia, Indonesia, and Thailand. The effects of activation temperature on the textural properties of the palm-shell activated carbons, namely

Jia Guo; Aik Chong Lua

2002-01-01

389

Kinetics of oxidation of carbon in liquid iron-carbon-silicon-manganese-sulfur alloys by carbon dioxide in nitrogen  

Microsoft Academic Search

The oxidation of carbon with the simultaneous oxidation of silicon, manganese, and iron of liquid alloys by carbon dioxide\\u000a in nitrogen and the absorption of oxygen by the alloys from the gas were studied using 1-g liquid iron droplets levitated\\u000a in a stream of the gas at 1575 C to 1715 C. Oxidation of carbon was favored over oxidation of

Haiping Sun; Robert D. Pehlke

1995-01-01

390

Process for removing sulfur from sulfur-containing gases  

SciTech Connect

This patent describes a process for reducing the level of sulfur dioxide in a sulfur dioxide- containing gas. It comprises preparing an aqueous slurry comprising a calcium alkali together with a calcium-reactive silica or alumina, the calcium alkali and calcium-reactive silica or alumina being introduced into the slurry in a form consisting essentially of a high calcium fly ash, which are present in amounts sufficient to allow for the formation of a sulfur dioxide-absorbing component which includes a calcium silicate or calcium aluminate; heating the slurry to a temperature between about 50{degrees} and 200{degrees} C. for between about 0.1 and about 24 hours to facilitate in the formation of the sulfur dioxide-absorbing component; contacting the gas with the slurry in a manner sufficient to allow for the absorption of sulfur dioxide by the absorbing component; and separating the absorbing component in the form of spent solids from the gas.

Rochelle, G.T.; Chang, J.C.S.

1991-09-10

391

Process for removing sulfur from sulfur-containing gases  

SciTech Connect

This patent describes a process for reducing the level of sulfur dioxide in a sulfur dioxide- containing gas. It comprises preparing an aqueous slurry comprising a calcium alkali together with a calcium-reactive silica or alumina which are present in amounts sufficient to allow for the formation of a sulfur dioxide-absorbing component which includes a calcium silicate or calcium aluminate; heating the slurry to a temperature between about 120{degrees} and 180{degrees} C. to facilitate in the formation of the sulfur dioxide-absorbing component; contacting the gas with the slurry in a manner sufficient to allow for the absorption of sulfur dioxide by the absorbing component; and separating the absorbing component in the form of spent solids from the gas.

Jozewicz, W.; Chang, J.C.S.; Sedman, C.B.; Brna, T.G.; Rochelle, G.T.

1991-09-10

392

Calcium looping process for high purity hydrogen production integrated with capture of carbon dioxide, sulfur and halides  

DOEpatents

A process for producing hydrogen comprising the steps of: (i) gasifying a fuel into a raw synthesis gas comprising CO, hydrogen, steam, sulfur and halide contaminants in the form of H.sub.2S, COS, and HX, wherein X is a halide; (ii) passing the raw synthesis gas through a water gas shift reactor (WGSR) into which CaO and steam are injected, the CaO reacting with the shifted gas to remove CO.sub.2, sulfur and halides in a solid-phase calcium-containing product comprising CaCO.sub.3, CaS and CaX.sub.2; (iii) separating the solid-phase calcium-containing product from an enriched gaseous hydrogen product; and (iv) regenerating the CaO by calcining the solid-phase calcium-containing product at a condition selected from the group consisting of: in the presence of steam, in the presence of CO.sub.2, in the presence of synthesis gas, in the presence of H.sub.2 and O.sub.2, under partial vacuum, and combinations thereof.

Ramkumar, Shwetha; Fan, Liang-Shih

2013-07-30

393

The reductive tricarboxylic acid cycle of carbon dioxide assimilation: initial studies and purification of ATP-citrate lyase from the green sulfur bacterium Chlorobium tepidum.  

PubMed Central

Carbon dioxide is fixed largely by the reductive tricarboxylic acid (RTCA) cycle in green sulfur bacteria. One of the key enzymes, ATP-citrate lyase, was purified to apparent homogeneity from the moderately thermophilic green sulfur bacterium Chlorobium tepidum. The molecular weight of the native enzyme was about 550,000, and the preponderance of evidence indicated that the protein is composed of identical subunits (Mr of approximately 135,000) which degraded to two major proteins with Mrs of approximately 65,000 and approximately 42,000. Western immunoblots and in vitro phosphorylation experiments indicated that these two species could have been the result of proteolysis by an endogenous protease, similar to what has been observed with mammalian, yeast, and mold ATP-citrate lyase. In addition to apparent structural similarities, the catalytic properties of C. tepidum ATP-citrate lyase showed marked similarities to the eukaryotic enzyme, with significant differences from other prokaryotic ATP-citrate lyases, including the enzyme from the closely related organism Chlorobium limicola. Phosphorylation of C. tepidum ATP-citrate lyase occurred, presumably on a histidine residue at the active site, similar to the case for the mammalian enzyme. In contrast to the situation observed for other prokaryotic ATP-citrate lyase enzymes, the C. tepidum enzyme was not able to replace ATP and GTP for activity or use Cu2+ to replace Mg2+ for enzyme activity. Given the apparent structural and catalytic similarities of the enzyme from C. tepidum and its eukaryotic counterpart, the C. tepidum system should serve as an excellent model for studies of the enzymology and regulation of this protein.

Wahlund, T M; Tabita, F R

1997-01-01

394

Volcanic Eruption Detection by the Total Ozone Mapping Spectrometer (TOMS) Instruments: a 22-Year Record of Sulfur Dioxide and Ash Emissions  

NASA Astrophysics Data System (ADS)

Since their first deployment in November 1978, the Total Ozone Mapping Spectrometer (TOMS) instruments have provided a unique, robust and near-continuous record of sulfur dioxide (SO2) and ash emissions from active volcanoes worldwide. Data from the four TOMS satellites that have flown to date (Nimbus-7, Meteor-3, ADEOS and Earth Probe) have been incorporated into a TOMS volcanic emissions database that presently covers 22 years of SO2 and ash emissions, representing one of the longest satellite-derived records of volcanic activity in existence. At the beginning of 2002, this database comprised 194 individual eruptive events produced during 100 eruptions from 60 volcanoes, resulting in a total of 666 days of volcanic cloud observations by TOMS. Regular eruptions of the African volcano Nyamuragira (DR Congo) since 1978, accompanied by copious SO2 production (Guth et al., 2002), have alone contributed approximately 20% of the days on which clouds were observed. Indonesian volcanoes have produced over 30% of detected eruptive events, due largely to frequent explosive activity at Galunggung, Soputan and Colo during the 1980s. The latest SO2 retrieval results from Earth Probe (EP) TOMS document a period (1996-2001) lacking large explosive eruptions, and also dominated by SO2 emission from 4 eruptions of Nyamuragira. EP TOMS has detected the SO2 and ash produced during 39 eruptive events from 15 volcanoes to date, with volcanic clouds observed on 128 days. Data from EP TOMS have recently begun to degrade, and its erstwhile successor (QuikTOMS) failed to achieve orbit in 2001. New SO2 algorithms are currently being developed for the Ozone Monitoring Instrument (OMI), which will continue the TOMS record of UV remote sensing of volcanic emissions from 2004. OMI will offer SO2 detection limits up to 50 times lower than TOMS and comparable to COSPEC, offering the prospect of regular space-based measurement of passive degassing. Reference: A.L. Guth, G.J.S. Bluth & S.A. Carn (2002). Analyzing sulfur dioxide emissions of Nyamuragira, Abstract (this meeting).

Carn, S. A.; Krueger, A. J.; Bluth, G. J.; Schaefer, S. J.; Krotkov, N. A.; Watson, I. M.; Datta, S.

2002-05-01

395

Rice husk ash/calcium oxide/ceria sorbent for simultaneous removal of sulfur dioxide and nitric oxide from flue gas at low temperature  

SciTech Connect

The reduction of sulfur dioxide (SO{sub 2}) and nitric oxide (NO) emissions has become an isssue of great importance to government regulatory agencies and general public due to their negative effect towards the environment and human health. In this work, the simultaneous removal of sulfur dioxide (SO{sub 2}) and nitric oxide (NO) from simulated flue gas was investigated in a fixed-bed reactor using rice husk ash (RHA)/CaO/CeO{sub 2} sorbent. Attention was focused on the major reactor operation parameters affecting sorption capacity of RHA/CaO/CeO{sub 2} sorbent, which include feed concentration of SO{sub 2} and NO, relative humidity (RH), operating temperature and space velocity (GHSV). This is because such information is unavailable for RHA-based sorbent and the effects of these parameters reported in the literature are also not reliable. Enhancement effect of NO on removal of SO{sub 2} was observed and the presence of SO{sub 2} was essential to the removal of NO. However, at a high level of SO{sub 2}/NO concentration, competition in the sorption of NO and SO{sub 2} on the sorbent active sites might have occurred. RH was found to significantly enhance the SO{sub 2} sorption of the RHA/CaO/CeO{sub 2} sorbent. By contrast, NO sorption capacity decreases when RH was further introduced, as it was not easy to sorb NO in the presence of water. Apart from that, the results also shows that there was a threshold value for the RH to ensure higher SO{sub 2} and NO removal and this value was observed at 50% RH. Higher operating temperatures were favored for SO{sub 2} and NO removal. Nevertheless, beyond 150 degrees C the SO{sub 2} removal was found to decrease. On the other hand, a lower space velocity resulted in a higher SO{sub 2} and NO removal.

Dahlan, I.; Lee, K.T.; Kamaruddin, A.H.; Mohamed, A.R. [University of Sains Malaysia, Pulau Pinang (Malaysia). School of Chemical Engineering

2009-06-15

396

Sensitive quantification of sulfur compounds in wine by headspace solid-phase microextraction technique  

Microsoft Academic Search

A sensitive solid-phase microextraction and gas chromatography-pulsed flame photometric detection technique was developed to quantify volatile sulfur compounds in wine. Eleven sulfur compounds, including hydrogen sulfide, methanethiol, ethanethiol, dimethyl sulfide, diethyl sulfide, methyl thioacetate, dimethyl disulfide, ethyl thioacetate, diethyl disulfide, dimethyl trisulfide and methionol, can be quantified simultaneously by employing three internal standards. Calibration curves were established in a synthetic

Yu Fang; Michael C. Qian

2005-01-01

397

I: THE INVESTIGATION OF THE CYCLOADDITION REACTIONS OF KETENE AND TERTBUTYL CYANOKETENE WITH AZOMETHINE GROUPS IN THE PRESENCE OF LIQUID SULFUR DIOXIDE. II: THE UTILIZATION OF THE UGI FOUR-COMPONENT CONDENSATION IN THE ASYMMETRIC SYNTHESIS OF NORFURANOMYCIN, A MODEL STUDY  

Microsoft Academic Search

I. The reaction of a ketene-sulfur dioxide adduct (15) with aryl aldehyde and ketone azines was investigated. Additional evidence for the existence of this adduct was obtained from its ('13)C nmr spectrum. Efforts to form an adduct with tert-butyl cyano ketene and sulfur dioxide, analogous to (15), were unsuccessful. Instead a previously unreported reaction took place with N-methyl aryl imines

ZENON LYSENKO

1980-01-01

398

Nu sub 1 plus nu sub 3 combination band of SO2. [measurement of infrared-active vibration-rotation fundamental bands of sulfur dioxide at high spectral resolution  

NASA Technical Reports Server (NTRS)

The infrared-active vibration-rotation combination band nu sub 1 + nu sub 3 of sulfur dioxide was measured with moderately high spectral resolution. Quantum number identifications of spectral lines were made by comparison with theoretically computed spectra which include the effects of centrifugal distortion. Relative line intensities were also calculated. The band center for nu sub 1 + nu sub 3 was determined to be 2499.60 + or - 0.10/cm.

Corice, R. J., Jr.; Fox, K.; Tejwani, G. D. T.

1972-01-01

399

Carbon nanotubes supported Cu-Ni bimetallic catalysts and their properties for the direct synthesis of dimethyl carbonate from methanol and carbon dioxide  

NASA Astrophysics Data System (ADS)

Multi-walled carbon nanotubes (MWCNTs) supported Cu-Ni bimetallic catalysts for the direct synthesis of dimethyl carbonate (DMC) from CH 3OH and CO 2 were synthesized and investigated. The supporting materials and the synthesized catalysts were fully characterized using FTIR, scanning electron microscopy (SEM), transmission electron microscopy (TEM), temperature-programmed reduction (TPR), X-ray diffraction (XRD) and X-ray photoelectron spectrum (XPS) techniques. The catalytic activities were investigated by performing micro-reactions. The experimental results showed that the metal phase and Cu-Ni alloy phase in the catalyst were partially formed during the calcination and activation step. Active metal particles were dispersed homogeneously on the surface of the MWCNTs. Cu-Ni/MWCNTs catalysts were efficient for the direct synthesis of DMC. The highest conversion of CH 3OH was higher than 4.3% and the selectivity of DMC was higher than 85.0% under the optimal catalytic conditions of 120 °C and around 1.2 MPa. The high catalytic activity of Cu-Ni/MWCNTs in DMC synthesis can be attributed to the synergetic effects of metal Cu, Ni and Cu-Ni alloy in the activation of CH 3OH and CO 2, the unique structure of MWCNTs and the interaction between the metal particles and the supports.

Bian, Jun; Xiao, Min; Wang, Shuan-Jin; Lu, Yi-Xin; Meng, Yue-Zhong

2009-05-01

400

A case study of the relative effects of power plant nitrogen oxides and sulfur dioxide emission reductions on atmospheric nitrogen deposition.  

PubMed

The contrasting effects of point source nitrogen oxides (NOx) and sulfur dioxide (SO2) air emission reductions on regional atmospheric nitrogen deposition are analyzed for the case study of a coal-fired power plant in the southeastern United States. The effect of potential emission reductions at the plant on nitrogen deposition to Escambia Bay and its watershed on the Florida-Alabama border is simulated using the three-dimensional Eulerian Community Multiscale Air Quality (CMAQ) model. A method to quantify the relative and individual effects of NOx versus SO2 controls on nitrogen deposition using air quality modeling results obtained from the simultaneous application of NOx and SO2 emission controls is presented and discussed using the results from CMAQ simulations conducted with NOx-only and SO2-only emission reductions; the method applies only to cases in which ambient inorganic nitrate is present mostly in the gas phase; that is, in the form of gaseous nitric acid (HNO3). In such instances, the individual effects of NOx and SO2 controls on nitrogen deposition can be approximated by the effects of combined NOx + SO2 controls on the deposition of NOy, (the sum of oxidized nitrogen species) and reduced nitrogen species (NHx), respectively. The benefit of controls at the plant in terms of the decrease in nitrogen deposition to Escambia Bay and watershed is less than 6% of the overall benefit due to regional Clean Air Interstate Rule (CAIR) controls. PMID:20397558

Vijayaraghavan, Krish; Seigneur, Christian; Bronson, Rochelle; Chen, Shu-Yun; Karamchandani, Prakash; Walters, Justin T; Jansen, John J; Brandmeyer, Jo Ellen; Knipping, Eladio M

2010-03-01

401

The Role of Sulfur Dioxide in the Regulation of Mitochondrion-Related Cardiomyocyte Apoptosis in Rats with Isopropylarterenol-Induced Myocardial Injury  

PubMed Central

The authors investigated the regulatory effects of sulfur dioxide (SO2) on myocardial injury induced by isopropylarterenol (ISO) hydrochloride and its mechanisms. Wistar rats were divided into four groups: control group, ISO group, ISO plus SO2 group, and SO2 only group. Cardiac function was measured and cardiomyocyte apoptosis was detected. Bcl-2, bax and cytochrome c (cytc) expressions, and caspase-9 and caspase-3 activities in the left ventricular tissues were examined in the rats. The opening status of myocardial mitochondrial permeability transition pore (MPTP) and membrane potential were analyzed. The results showed that ISO-treated rats developed heart dysfunction and cardiac injury. Furthermore, cardiomyocyte apoptosis in the left ventricular tissues was augmented, left ventricular tissue bcl-2 expression was down-regulated, bax expression was up-regulated, mitochondrial membrane potential was significantly reduced, MPTP opened, cytc release from mitochondrion into cytoplasm was significantly increased, and both caspase-9 and caspase-3 activities were increased. Administration of an SO2 donor, however, markedly improved heart function and relieved myocardial injury of the ISO-treated rats; it lessened cardiomyocyte apoptosis, up-regulated myocardial bcl-2, down-regulated bax expression, stimulated mitochondrial membrane potential, closed MPTP, and reduced cytc release as well as caspase-9 and caspase-3 activities in the left ventricular tissue. Hence, SO2 attenuated myocardial injury in association with the inhibition of apoptosis in myocardial tissues, and the bcl-2/cytc/caspase-9/caspase-3 pathway was possibly involved in this process.

Jin, Hongfang; Liu, Angie Dong; Holmberg, Lukas; Zhao, Manman; Chen, Siyao; Yang, Jinyan; Sun, Yan; Chen, Shanshan; Tang, Chaoshu; Du, Junbao

2013-01-01

402

Growth response of four species of Eastern hardwood tree seedlings exposed to ozone, acidic precipitation, and sulfur dioxide. [Prunus serotina, Acer rubrum, Quercus rubra, Liriodendron tulipifera  

SciTech Connect

In 1987 a study was conducted in controlled environment chambers to determine the foliar sensitivity of tree seedlings of eight species to ozone and acidic precipitation, and to determine the influence of leaf position on symptom severity. Jensen and Dochinger conducted concurrent similar studies in Continuously Stirred Tank Reactor (CSTR) chambers with ten species of forest trees. Based on the results of these initial studies, four species representing a range in foliar sensitivity to ozone were chosen: black cherry (Prunus serotina Ehrh.), red maple (Acer rubrum L.), northern red oak (Quercus rubra L.) and yellow-poplar (Liriodendron tulipifera L.). These species were also chosen because of their ecological and/or commercial importance in Pennsylvania. Seedlings were exposed in growth chambers simulated acid rain. In addition acute exposures to sulfur dioxide were conducted in a regime based on unpublished monitoring data collected near coal-fired power plants. The objective of this study was to determine if the pollutant treatments influenced the growth and productivity of seedlings of these four species. This information will help researchers and foresters understand the role of air pollution in productivity of eastern forests.

Davis, D.D. Skelly, J.M. (Pennsylvania State Univ., University Park (United States))

1992-03-01

403

Distribution, metabolism and toxicity of inhaled sulfur dioxide and endogenously generated sulfite in the respiratory tract of normal and sulfite oxidase-deficient rats  

SciTech Connect

We report on the distribution, metabolism, and toxicity of sulfite in the respiratory tract and other tissues of rats exposed to endogenously generated sulfite or to inhaled sulfur dioxide (SO/sub 2/). Graded sulfite oxidase deficiency was induced in several groups of rats by manipulating their tungsten to molybdenum intake ratio. Endogenously generated sulfite and S-sulfonate compounds (a class of sulfite metabolite) accumulated in the respiratory tract tissues and in the plasma of these rats in inverse proportion to hepatic sulfite oxidase activity. In contrast to this systemic mode of exposure, sulfite exposure of normal, sulfite oxidase-competent rats via inhaled SO/sub 2/ (10 and 30 ppm) was restricted to the airways. Minor pathological changes consisting of epithelial hyperplasia, mucoid degeneration, and desquamation of epithelium were observed only in the tracheas and bronchi of the rats inhaling SO/sub 2/, even though the concentration of sulfite plus S-sulfonates in the tracheas and bronchi of these rats was considerably lower than that in the endogenously exposed rats. We attribute this histological damage to hydrogen ions stemming from inhaled SO/sub 2/, not to the sulfite/bisulfite ions that are also a product of inhaled SO/sub 2/. In addition to the lungs and trachea, all other tissues examined, except the testes, appeared to be refractory to high concentrations of endogenously generated sulfite. The testes of grossly sulfite oxidase-deficient rats were severely atrophied and devoid of spermatogenic cells.

Gunnison, A.F.; Sellakumar, A.; Currie, D.; Snyder, E.A.

1987-01-01

404

EPR characterization of ascorbyl and sulfur dioxide anion radicals trapped during the reaction of bovine Cytochrome c Oxidase with molecular oxygen  

NASA Astrophysics Data System (ADS)

The reaction intermediates of reduced bovine Cytochrome c Oxidase (C cO) were trapped following its reaction with oxygen at 50 ?s-6 ms by innovative freeze-quenching methods and studied by EPR. When the enzyme was reduced with either ascorbate or dithionite, distinct radicals were generated; X-band (9 GHz) and D-band (130 GHz) CW-EPR measurements support the assignments of these radicals to ascorbyl and sulfur dioxide anion radical ( SO2-rad ), respectively. The X-band spectra show a linewidth of 12 G for the ascorbyl radical and 11 G for the SO2-rad radical and an isotropic g-value of 2.005 for both species. The D-band spectra reveal clear distinctions in the g-tensors and powder patterns of the two species. The ascorbyl radical spectrum displays approximate axial symmetry with g-values of g x = 2.0068, g y = 2.0066, and g z = 2.0023. The SO2-rad radical has rhombic symmetry with g-values of g x = 2.0089, g y = 2.0052, and g z = 2.0017. When the contributions from the ascorbyl and SO2-rad radicals were removed, no protein-based radical on C cO could be identified in the EPR spectra.

Yu, Michelle A.; Egawa, Tsuyoshi; Yeh, Syun-Ru; Rousseau, Denis L.; Gerfen, Gary J.

2010-04-01

405

Soap bubbles in analytical chemistry. Conductometric determination of sub-parts per million levels of sulfur dioxide with a soap bubble.  

PubMed

Soap bubbles provide a fascinating tool that is little used analytically. With a very low liquid volume to surface area ratio, a soap bubble can potentially provide a very useful interface for preconcentration where mass transfer to an interfacial surface is important. Here we use an automated system to create bubbles of uniform size and film thickness. We utilize purified Triton-X 100, a nonionic surfactant, to make soap bubbles. We use such bubbles as a gas-sampling interface. Incorporating hydrogen peroxide into the bubble provides a system where electrical conductance increases as the bubble is exposed to low concentrations of sulfur dioxide gas. We theoretically derive the conductance of a hollow conducting spherical thin film with spherical cap electrodes. We measure the film thickness by incorporating a dye in the bubble making solution and laser transmission photometry and find that it agrees well with the geometrically computed thickness. With the conductance of the bubble-making soap solution being measured by conventional methods, we show that the measured values of the bubble conductance with known bubble and electrode dimensions closely correspond to the theoretically computed value. Finally, we demonstrate that sub-ppm levels of SO(2) can readily be detected by the conductivity change of a hydrogen peroxide-doped soap bubble, measured in situ, when the gas flows around the bubble. PMID:16615794

Kanyanee, Tinakorn; Borst, Walter L; Jakmunee, Jaroon; Grudpan, Kate; Li, Jianzhong; Dasgupta, Purnendu K

2006-04-15

406

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

407

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

NASA Astrophysics Data System (ADS)

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°C onward and thiol synthesis above 75°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 systhesis. 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.

Heinen, Wolfgang; Lauwers, Anne Marie

1996-04-01

408

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

409

Process for removing sulfur from sulfur-containing gases  

SciTech Connect

This patent describes a process for reducing the level of sulfur in a sulfur dioxide-containing gas. It comprises: preparing an aqueous slurry comprising a calcium alkali together with a calcium-reactive silica or alumina which are present in amounts sufficient to allow for the formation of a sulfur dioxide-absorbing component which includes a calcium silicate or calcium aluminate; heating the slurry to a temperature between about 40{degrees} and about 200{degrees} C. to facilitate in the formation of the sulfur dioxide-absorbing component; contacting the gas with the slurry in a manner sufficient to allow for the absorption of sulfur dioxide by the absorbing component; and separating the absorbing component in the form of spent solids from the gas.

Rochelle, G.T.; Jozewicz, W.

1990-06-05

410

Spectroscopic study for photocatalytic decomposition of organic compounds on titanium dioxide containing sulfur under visible light irradiation.  

PubMed

Yellowish S-containing TiO2 (S-TiO2) powders were prepared by calcination of a mixture of titanium(III) chloride and ammonium thiocyanate solutions. Three kinds of S-TiO2 were prepared by varying the concentration of ammonium thiocyanate (0.5, 1 or 13 M). X-ray photoelectron spectroscopy spectra of the S-TiO2 showed that sulfur atoms existed on the surface of TiO2 powders. But the peaks assigned to S disappeared after Ar+ etching, which means that these atoms were not doped in the bulk of the TiO2 powders. While UV-visible absorption spectra of S-TiO2 showed that the absorption edges of these photocatalysts were seen to shift to a longer wavelength (lower band gap energy) than those of undoped rutile TiO2 prepared and commercial anatase type TiO2 (ST-01). The S-TiO2 (1 M) exhibited higher photocatalytic activity than ST-01 for degradation of methylene blue in aqueous solution under visible light irradiation (lambda > 400 nm). It was also confirmed by IR spectroscopy that acetaldehyde in oxygen under visible light irradiation (lambda > 400 nm) was decomposed to acetic acid by the S-TiO2 and ST-01 at the first decomposition step. PMID:16527296

Katoh, Masahiro; Aihara, Hironori; Horikawa, Toshihide; Tomida, Tahei

2006-06-15

411

High Purity Hydrogen Production with In-Situ Carbon Dioxide and Sulfur Capture in a Single Stage Reactor  

SciTech Connect

Enhancement in the production of high purity hydrogen (H{sub 2}) from fuel gas, obtained from coal gasification, is limited by thermodynamics of the water gas shift (WGS) reaction. However, this constraint can be overcome by conducting the WGS in the presence of a CO{sub 2}-acceptor. The continuous removal of CO{sub 2} from the reaction mixture helps to drive the equilibrium-limited WGS reaction forward. Since calcium oxide (CaO) exhibits high CO{sub 2} capture capacity as compared to other sorbents, it is an ideal candidate for such a technique. The Calcium Looping Process (CLP) developed at The Ohio State University (OSU) utilizes the above concept to enable high purity H{sub 2} production from synthesis gas (syngas) derived from coal gasification. The CLP integrates the WGS reaction with insitu CO{sub 2}, sulfur and halide removal at high temperatures while eliminating the need for a WGS catalyst, thus reducing the overall footprint of the hydrogen production process. The CLP comprises three reactors - the carbonator, where the thermodynamic constraint of the WGS reaction is overcome by the constant removal of CO{sub 2} product and high purity H{sub 2} is produced with contaminant removal; the calciner, where the calcium sorbent is regenerated and a sequestration-ready CO{sub 2} stream is produced; and the hydrator, where the calcined sorbent is reactivated to improve its recyclability. As a part of this project, the CLP was extensively investigated by performing experiments at lab-, bench- and subpilot-scale setups. A comprehensive techno-economic analysis was also conducted to determine the feasibility of the CLP at commercial scale. This report provides a detailed account of all the results obtained during the project period.

Nihar Phalak; Shwetha Ramkumar; Daniel Connell; Zhenchao Sun; Fu-Chen Yu; Niranjani Deshpande; Robert Statnick; Liang-Shih Fan

2011-07-31

412

Photooxidation of dimethyl sulfide and dimethyl disulfide. II - Mechanism evaluation  

NASA Astrophysics Data System (ADS)

The mechanisms for atmospheric photooxidation of CH3SCH3 and CH3SSCH3 are evaluated with a set of outdoor smog chamber studies of CH3SCH3 and CH3SSCH3 photooxidation in the presence or absence of NO(x). A study was conducted over a range of initial conditions relevant to both the clean and polluted troposphere in order to determine yields of the major gas-phase and aerosol-phase products, sulfur dioxide, formaldehyde, sulfuric acid, and methanesulfonic acid. Kinetic simulations are compared to experimental observations and the results of these comparisons are discussed with respect to known tenets of atmospheric chemistry of organosulfur compounds.

Yin, Fangdong; Grosjean, Daniel; Flagan, Richard C.; Seinfeld, John H.

1990-11-01

413

Studies on air pollution: Effects of nitrogen dioxide on airway caliber and reactivity in asthmatic subjects; effects of nitrogen dioxide on lung lymphocytes and macrophage products in healthy subjects; nasal and bronchial effects of sulfur dioxide in asthmatic subjects. Final report, 26 June 1987-26 November 1988  

SciTech Connect

The investigators performed three studies of the effects of NO/sub 2/ and SO/sub 2/ on airway function in human subjects. In 9 exercising asthmatic subjects, a 30-min exposure to 0.3 ppm nitrogen dioxide did not alter specific airway resistance, maximal expiratory flow, or the slope of phase III on the single breath test of nitrogen distribution and had no effect on airway hyperresponsiveness to sulfur dioxide. In the second study, repeated exposure of 5 healthy subjects to nitrogen dioxide was associated neither with any significant change in pulmonary function nor in the levels of secretory product of lung macrophages in bronchoalveolar lavage fluid. Analysis of the numbers and types of lymphocytes in venous blood and bronchoalveolar lavage fluid revealed no change apart from a small, possibly artifactual increase in natural killer cells in bronchoalveolar lavage fluid after NO/sub 2/ exposure. The third study examined whether brief exposures to moderately high concentrations of SO/sub 2/ caused acute increases in nasal symptoms and nasal resistance in 8 subjects with a history of both asthma and allergic rhinitis and with demonstrable bronchial hyperreactivity to SO/sub 2/.

Boushey, H.A.; Rubinstein, I.; Bigby, B.G.

1988-12-13

414

Replacement of hazardous chromium impregnating agent from silver/copper/chromium-impregnated active carbon using triethylenediamine to remove hydrogen sulfide, trichloromethane, ammonia, and sulfur dioxide.  

PubMed

Activated carbon (AC) is widely used as an effective adsorbent in many applications, including industrial-scale air purification systems and air filter systems in gas masks. In general, ACs without chemical impregnation are good adsorbents of organic vapors but poor adsorbents of low-molecular-weight or polar gases such as chlorine, sulfur dioxide (SO2), formaldehyde, and ammonia (NH3). Impregnated ACs modified with metallic impregnating agents (ASC-carbons; e.g., copper, chromium, and silver) enhance the adsorbing properties of the ACs for simultaneously removing specific poisonous gases, but disposal of the chromium metal salt used to impregnate the ACs has the potential to result in situations that are toxic to both humans and the environment, thereby necessitating the search for replaceable organic impregnating agents that represent a much lower risk. The aim of this study was to assess the gas removal efficiency of an AC in which the organic impregnating agent triethylenediamine (TEDA) largely replaced the metallic impregnating agent chromium. We assessed batch and continuous adsorption capacities in situ for removing simulated hydrogen sulfide (H2S), trichloromethane (CHCl3), NH3, and SO2 gases. Brunauer-Emmet-Teller measurements and scanning electron microscopy analyses identified the removal mechanism by which TEDA-impregnated AS-carbon (dechromium ASC-carbon) adsorbs gases and determined the removal capacity for H2S, CHCl3, NH3, and SO2 to be 311, 258, 272, and 223 mg/g-C, respectively. These results demonstrate that TEDA-impregnated AS-carbon is significantly more efficient than ASC-carbon in adsorbing these four gases. Organic TEDA-impregnating agents have also been proven to be a reliable and environmental friendly agent and therefore a safe replacement of the hazardous chromium found in conventional ASC-carbon used in removing toxic gases from the airstream. PMID:19320264

Wu, Li-Chun; Chung, Ying-Chien

2009-03-01

415

Attribution of primary formaldehyde and sulfur dioxide at Texas City during SHARP/formaldehyde and olefins from large industrial releases (FLAIR) using an adjoint chemistry transport model  

NASA Astrophysics Data System (ADS)

adjoint version of the Houston Advanced Research Center (HARC) neighborhood air quality model with 200 m horizontal resolution, coupled offline to the Quick Urban & Industrial Complex (QUIC-URB) fast response urban wind model, was used to perform 4-D variational (4Dvar) inverse modeling of an industrial release of formaldehyde (HCHO) and sulfur dioxide (SO2) in Texas City, Texas during the 2009 Study of Houston Atmospheric Radical Precursors (SHARP). The source attribution was based on real-time observations by the Aerodyne mobile laboratory and a high resolution 3-D digital model of the emitting petrochemical complex and surrounding urban canopy. The inverse model estimate of total primary HCHO emitted during the incident agrees very closely with independent remote sensing estimates based on both Imaging and Multi-Axis Differential Optical Absorption Spectroscopy (DOAS). Whereas a previous analysis of Imaging DOAS data attributed the HCHO release to a Fluidized Catalytic Cracking Unit (FCCU), the HARC model attributed most of the HCHO event emissions to both the FCCU and desulfurization processes. Fugitives contributed significantly to primary HCHO, as did combustion processes, whereas the latter accounted for most SO2 event emissions. The inferred HCHO-to-SO2 molar emission ratio was similar to that computed directly from ambient air measurements during the release. The model-estimated HCHO-to-CO molar emission ratio for combustion units with significant inferred emissions ranged from 2% to somewhat less than 7%, consistent with other observationally-based estimates obtained during SHARP. A model sensitivity study demonstrated that the inclusion of urban morphology has a significant, but not critical, impact on the source attribution.

Olaguer, Eduardo P.; Herndon, Scott C.; Buzcu-Guven, Birnur; Kolb, Charles E.; Brown, Michael J.; Cuclis, Alex E.

2013-10-01

416

A novel lithium/sulfur battery based on sulfur/graphene nanosheet composite cathode and gel polymer electrolyte  

PubMed Central

A novel sulfur/graphene nanosheet (S/GNS) composite was prepared via a simple ball milling of sulfur with commercial multi-layer graphene nanosheet, followed by a heat treatment. High-resolution transmission and scanning electronic microscopy observations showed the formation of irregularly interlaced nanosheet-like structure consisting of graphene with uniform sulfur coating on its surface. The electrochemical properties of the resulting composite cathode were investigated in a lithium cell with a gel polymer electrolyte (GPE) prepared by trapping 1 mol dm?3 solution of lithium bistrifluoromethanesulfonamide in tetraethylene glycol dimethyl ether in a polymer matrix composed of poly(vinylidene fluoride-co-hexafluoropropylene)/poly(methylmethacrylate)/silicon dioxide (PVDF-HFP/PMMA/SiO2). The GPE battery delivered reversible discharge capacities of 809 and 413 mAh g?1 at the 1st and 50th cycles at 0.2C, respectively, along with a high coulombic efficiency over 50 cycles. This performance enhancement of the cell was attributed to the suppression of the polysulfide shuttle effect by a collective effect of S/GNS composite cathode and GPE, providing a higher sulfur utilization.

2014-01-01

417

A novel lithium/sulfur battery based on sulfur/graphene nanosheet composite cathode and gel polymer electrolyte  

NASA Astrophysics Data System (ADS)

A novel sulfur/graphene nanosheet (S/GNS) composite was prepared via a simple ball milling of sulfur with commercial multi-layer graphene nanosheet, followed by a heat treatment. High-resolution transmission and scanning electronic microscopy observations showed the formation of irregularly interlaced nanosheet-like structure consisting of graphene with uniform sulfur coating on its surface. The electrochemical properties of the resulting composite cathode were investigated in a lithium cell with a gel polymer electrolyte (GPE) prepared by trapping 1 mol dm-3 solution of lithium bistrifluoromethanesulfonamide in tetraethylene glycol dimethyl ether in a polymer matrix composed of poly(vinylidene fluoride-co-hexafluoropropylene)/poly(methylmethacrylate)/silicon dioxide (PVDF-HFP/PMMA/SiO2). The GPE battery delivered reversible discharge capacities of 809 and 413 mAh g-1 at the 1st and 50th cycles at 0.2C, respectively, along with a high coulombic efficiency over 50 cycles. This performance enhancement of the cell was attributed to the suppression of the polysulfide shuttle effect by a collective effect of S/GNS composite cathode and GPE, providing a higher sulfur utilization. PACS: 82.47.Aa; 82.45.Gj; 62.23.Kn

Zhang, Yongguang; Zhao, Yan; Bakenov, Zhumabay

2014-03-01

418

Aspects of carbon dioxide utilization  

Microsoft Academic Search

Carbon dioxide reacts with hydrogen, alcohols, acetals, epoxides, amines, carbon–carbon unsaturated compounds, etc. in supercritical carbon dioxide or in other solvents in the presence of metal compounds as catalysts. The products of these reactions are formic acid, formic acid esters, formamides, methanol, dimethyl carbonate, alkylene carbonates, carbamic acid esters, lactones, carboxylic acids, polycarbonate (bisphenol-based engineering polymer), aliphatic polycarbonates, etc. Especially,

Iwao Omae

2006-01-01

419

Sulfur Oxides: Current Status of Knowledge. Final Report.  

National Technical Information Service (NTIS)

The report is a state-of-the-art review on sulfur oxides, including sulfur dioxide, sulfurous and sulfuric acid, sulfates, sulfites, and bisulfites. The report considers the interaction of sulfur oxides with other pollutants that may be associated with he...

A. V. Colucci

1976-01-01

420

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

421

DSRP, Direct Sulfur Production  

Microsoft Academic Search

Hot-gas desulfurization processes for IGCC and other advanced power applications utilize regenerable mixed-metal oxide sorbents to remove hydrogen sulfide (HâS) from raw coal gas. Regeneration of these sorbents produces an off-gas typically containing I to 3 percent sulfur dioxide (SOâ). Production of elemental sulfur is a highly desirable option for the ultimate disposal of the SOâ content of this off-gas.

S. K. Gangwal; W. J. McMichael; S. K. Agarwal; B. L. Jang; G. B. Howe; D. H. Chen; J. R. Hopper

1993-01-01

422

Removal of dimethyl sulfide by the combination of non-thermal plasma and biological process.  

PubMed

A bench scale system integrated with a non-thermal plasma (NTP) and a biotricking filtration (BTF) unit for the treatment of gases containing dimethyl sulfide (DMS) was investigated. DMS removal efficiency in the integrated system was up to 96%. Bacterial communities in the BTF were assessed by PCR-DGGE, which play the dominant role in the biological processes of metabolism, sulfur oxidation, sulfate-reducing and carbon oxidation. The addition of ozone from NTP made microbial community in BTF more complicated and active for DMS removal. The NTP oxidize DMS to simple compounds such as methanol and carbonyl sulfide; the intermediate organic products and DMS are further oxidized to sulfate, carbon dioxide, water vapors by biological degradation. These results show that NTP-BTF is achievable and open new possibilities for applying the integrated with NTP and BTF to odour gas treatment. PMID:23954717

Wei, Z S; Li, H Q; He, J C; Ye, Q H; Huang, Q R; Luo, Y W

2013-10-01

423

Determination of free sulfites (SO3-2) in dried fruits processed with sulfur dioxide by ion chromatography through anion exchange column and conductivity detection.  

PubMed

A simple and effective anion ion chromatography (IC) method with anion exchange column and conductivity detector has been developed to determine free sulfites (SO3-2) in dried fruits processed with sulfur dioxide. No oxidation agent, such as hydrogen peroxide, is used to convert sulfites to sulfates for IC analysis. In addition, no stabilizing agent, such as formaldehyde, fructose or EDTA, is required during the sample extraction. This method uses aqueous 0.2 N NaOH as the solvent for standard preparation and sample extraction. The sulfites, either prepared from standard sodium sulfite powder or extracted from food samples, are presumed to be unbound SO3-2 in aqueous 0.2 N NaOH (pH > 13), because the bound sulfites in the sample matrix are released at pH > 10. In this study, sulfites in the standard solutions were stable at room temperature (i.e., 15-25 degrees C) for up to 12 days. The lowest standard of the linear calibration curve is set at 1.59 microg/mL SO3-2 (equivalent to 6.36 microg/g sample with no dilution) for analysis of processed dried fruits that would contain high levels (>1000 microg/g) of sulfites. As a consequence, this method typically requires significant dilution of the sample extract. Samples are prepared with a simple procedure of sample compositing, extraction with aqueous 0.2 N NaOH, centrifugation, dilution as needed, and filtration prior to IC. The sulfites in these sample extracts are stable at room temperature for up to 20 h. Using anion IC, the sulfites are eluted under isocratic conditions with 10 mM aqueous sodium carbonate solution as the mobile phase passing through an anion exchange column. The sulfites are easily separated, with an analysis run time of 18 min, regardless of the dried fruit matrix. Recoveries from samples spiked with sodium sulfites were demonstrated to be between 81 and 105% for five different fruit matrixes (apricot, golden grape, white peach, fig, and mango). Overall, this method is simple to perform and effective for the determination of high levels of sulfites in dried fruits. PMID:24282955

Liao, Benjamin S; Sram, Jacqueline C; Files, Darin J

2013-01-01

424

Sulfur dioxide inhibits vascular smooth muscle cell proliferation via suppressing the Erk/MAP kinase pathway mediated by cAMP/PKA signaling  

PubMed Central

The present study was designed to investigate the role of endogenous sulfur dioxide (SO2) in vascular smooth muscle cell (VSMC) proliferation, and explore the possible role of cross-talk between cyclic adenosine monophosphate (cAMP)/protein kinase A (PKA) and extracellular signal-regulated kinase (Erk)/mitogen-activated protein kinase (MAPK) pathways in this action. By cell counting, growth curve depict, flow cytometry and bromodeoxyuridine (BrdU) labeling assays, we found that SO2 inhibited VSMC proliferation by preventing cell cycle progression from G1 to S phase and by reducing DNA synthesis. SO2 synthase aspartate aminotransferase (AAT1 and AAT2) overexpression significantly inhibited serum-induced proliferating cell nuclear antigen (PCNA) protein expression in VSMCs, demonstrated by western blot analysis. Moreover, overexpression of AAT1 or AAT2 markedly reduced incorporation of BrdU in serum-treated VSMCs. By contrast, either AAT1 or AAT2 knockdown significantly exacerbated serum-stimulated VSMC proliferation. Thus, both exogenous- and endogenous-derived SO2 suppressed serum-induced VSMC proliferation. However, annexin V-propidium iodide (PI) staining and cell cycle analysis demonstrated that SO2 did not influence VSMC apoptosis in the serum-induced proliferation model. In a platelet-derived growth factor (PDGF)-BB-stimulated VSMC proliferation model, SO2 dephosphorylated the active sites of Erk1/2, MAPK kinase 1/2 and RAF proto-oncogene serine/threonine-protein kinase (c-Raf) induced by PDGF-BB. However, the inactivation of the three kinases of the Erk/MAPK pathway was not due to the separate interferences on them by SO2 simultaneously, but a consequence of the influence on the upstream activity of the c-Raf molecule. Hence, we examined the cAMP/PKA pathway, which could inhibit Erk/MAPK transduction in VSMCs. The results showed that SO2 could stimulate the cAMP/PKA pathway to block c-Raf activation, whereas the Ser259 site on c-Raf had an important role in SO2-induced suppression of Erk/MAPK pathway. The present study firstly demonstrated that SO2 exerted a negative regulation of VSMC proliferation via suppressing the Erk/MAPK pathway mediated by cAMP/PKA signaling.

Liu, D; Huang, Y; Bu, D; Liu, A D; Holmberg, L; Jia, Y; Tang, C; Du, J; Jin, H

2014-01-01

425

Sulfur dioxide (SO2) as observed by MIPAS/Envisat: temporal development and spatial distribution at 15-45 km altitude  

NASA Astrophysics Data System (ADS)

We present a climatology of monthly and 10° zonal mean profiles of sulfur dioxide (SO2) volume mixing ratios (vmr) derived from MIPAS/Envisat measurements in the altitude range 15-45 km from July 2002 until April 2012. The vertical resolution varies from 3.5-4 km in the lower stratosphere up to 6-10 km at the upper end of the profiles with estimated total errors of 5-20 pptv for single profiles of SO2. Comparisons with few available observations of SO2 up to high altitudes from ATMOS, for a volcanically perturbed situations from ACE-FTS and, at the lowest altitudes, with stratospheric in-situ observations reveal general consistency of the datasets. The observations are the first empirical confirmation of features of the stratospheric SO2 distribution which have only been shown by models up to now: (1) the local maximum of SO2 at around 25-30 km altitude which is explained by the conversion of carbonyl sulfide (COS) as the precursor of the Junge layer, and (2) the downwelling of SO2 rich air to altitudes of 25-30 km at high latitudes during winter and its subsequent depletion on availability of sunlight. This has been proposed as the reason for the sudden appearance of enhanced concentrations of condensation nuclei during Arctic and Antarctic spring. Further, the strong increase of SO2 to values of 80-100 pptv in the upper stratosphere through photolysis of H2SO4 has been confirmed. Lower stratospheric variability of SO2 could mainly be explained by volcanic activity and no hint for a strong anthropogenic influence has been found. Regression analysis revealed a QBO (quasi-biennial oscillation) signal of the SO2 time series in the tropics at about 30-35 km, a SAO (semi-annual oscillation) signal at tropical and subtropical latitudes above 32 km and annual periodics predominantly at high latitudes. Further, the analysis indicates a correlation with the solar cycle in the tropics and southern subtropics above 30 km. Significant negative linear trends are found in the tropical lower stratosphere, probably due to reduced tropical volcanic activity and at southern mid-latitudes above 35 km. A positive trend is visible in the lower and middle stratosphere at polar to subtropical southern latitudes.

Höpfner, M.; Glatthor, N.; Grabowski, U.; Kellmann, S.; Kiefer, M.; Linden, A.; Orphal, J.; Stiller, G.; von Clarmann, T.; Funke, B.

2013-05-01

426

Sulfur dioxide (SO2) as observed by MIPAS/Envisat: temporal development and spatial distribution at 15-45 km altitude  

NASA Astrophysics Data System (ADS)

We present a climatology of monthly and 10° zonal mean profiles of sulfur dioxide (SO2) volume mixing ratios (vmr) derived from MIPAS/Envisat measurements in the altitude range 15-45 km from July 2002 until April 2012. The vertical resolution varies from 3.5-4 km in the lower stratosphere up to 6-10 km at the upper end of the profiles, with estimated total errors of 5-20 pptv for single profiles of SO2. Comparisons with the few available observations of SO2 up to high altitudes from ATMOS for a volcanically perturbed situation from ACE-FTS and, at the lowest altitudes, with stratospheric in situ observations reveal general consistency of the datasets. The observations are the first empirical confirmation of features of the stratospheric SO2 distribution, which have only been shown by models up to now: (1) the local maximum of SO2 at around 25-30 km altitude, which is explained by the conversion of carbonyl sulfide (COS) as the precursor of the Junge layer; and (2) the downwelling of SO2-rich air to altitudes of 25-30 km at high latitudes during winter and its subsequent depletion on availability of sunlight. This has been proposed as the reason for the sudden appearance of enhanced concentrations of condensation nuclei during Arctic and Antarctic spring. Further, the strong increase of SO2 to values of 80-100 pptv in the upper stratosphere through photolysis of H2SO4 has been confirmed. Lower stratospheric variability of SO2 could mainly be explained by volcanic activity, and no hints of a strong anthropogenic influence have been found. Regression analysis revealed a QBO (quasi-biennial oscillation) signal of the SO2 time series in the tropics at about 30-35 km, an SAO (semi-annual oscillation) signal at tropical and subtropical latitudes above 32 km and annual periodics predominantly at high latitudes. Further, the analysis indicates a correlation with the solar cycle in the tropics and southern subtropics above 30 km. Significant negative linear trends are found in the tropical lower stratosphere, probably due to reduced tropical volcanic activity and at southern mid-latitudes above 35 km. A positive trend is visible in the lower and middle stratosphere at polar to subtropical southern latitudes.

Höpfner, M.; Glatthor, N.; Grabowski, U.; Kellmann, S.; Kiefer, M.; Linden, A.; Orphal, J.; Stiller, G.; von Clarmann, T.; Funke, B.; Boone, C. D.

2013-10-01

427

Elemental sulfur recovery process  

DOEpatents

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

Flytzani-Stephanopoulos, M.; Zhicheng Hu.

1993-09-07

428

Elemental sulfur recovery process  

DOEpatents

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

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

1993-01-01

429

Method of detecting sulfur dioxide  

DOEpatents

(CH.sub.3).sub.3 SiNSO is produced by the reaction of ((CH.sub.3).sub.3 Si).sub.2 NH with SO.sub.2. Also produced in the reaction are ((CH.sub.3).sub.3 Si).sub.2 O and a new solid compound [NH.sub.4 ][(CH.sub.3).sub.3 SiOSO.sub.2 ]. Both (CH.sub.3).sub.3 SiNSO and [NH.sub.4 ][(CH.sub.3).sub.3 SiOSO.sub.2 ] have fluorescent properties. The reaction of the subject invention is used in a method of measuring the concentration of SO.sub.2 pollutants in gases. By the method, a sample of gas is bubbled through a solution of ((CH.sub.3).sub.3 Si).sub.2 NH, whereby any SO.sub.2 present in the gas will react to produce the two fluorescent products. The measured fluorescence of these products can then be used to calculate the concentration of SO.sub.2 in the original gas sample. The solid product [NH.sub.4][(CH.sub.3).sub.3 SiOSO.sub.2 ] may be used as a standard in solid state NMR spectroscopy.

Spicer, Leonard D. (Salt Lake City, UT); Bennett, Dennis W. (Clemson, SC); Davis, Jon F. (Salt Lake City, UT)

1985-01-01

430

78 FR 5303 - Approval and Promulgation of Implementation Plans; State of Missouri; Control of Sulfur Emissions...  

Federal Register 2010, 2011, 2012, 2013

...area by limiting sulfur dioxide (SO 2 ) emissions (a precursor pollutant to PM 2.5 ), from industrial boilers...area by limiting sulfur dioxide (SO 2 ) emissions (a precursor pollutant to PM 2.5 ), from industrial...

2013-01-25

431

TOTAL SULFUR DEPOSITION (WET+DRY) FROM THE ATMOSPHERE  

EPA Science Inventory

Sulfur Dioxide (SO2) is emitted primarily as a by-product of coal combustion from power plants. Sulfur Dioxide reacts in the atmosphere to form other chemical such as Sulfuric Acid and Amonium Sulfate. These compounds and their secondarily formed constituents deposit to the sur...

432

TOTAL SULFUR DEPOSITION (WET+DRY) FROM THE ATMOSHERE  

EPA Science Inventory

Sulfur Dioxide (SO2) is emitted primarily as a by-product of coal combustion from power plants. Sulfur Dioxide reacts in the atmosphere to form other chemical such as Sulfuric Acid and Amonium Sulfate. These compounds and their secondarily formed constituents deposit to the sur...

433

A spectroscopic identification of the products formed in the gas-phase reaction of OH with the atmospheric sulfur compounds: CHâSH, CHâSSCHâ and SOâ  

Microsoft Academic Search

The mechanism for the conversion of naturally occurring atmospheric sulfur compounds to sulfur dioxide is not yet established. The sulfur dioxide produced during degradation of sulfur compounds can undergo further chemical and\\/or physical interactions to form sulfuric acid, which is one of the components of acid rain. A number of sulfur compounds have been detected in the atmosphere; COS (carbonyl

S. C. Bhatia; J. H. Jr. Hall

1986-01-01

434

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

435

APPLICATION OF AN SO2-DENUDER FOR CONTINUOUS MEASUREMENT OF SULFUR IN SUBMICROMETRIC AEROSOLS  

EPA Science Inventory

A method is described for the continuous measurement of total sulfur in submicrometric aerosols suspended in air containing sulfur dioxide. The aerocolloid is passed through a tube coated internally with lead dioxide. The gaseous sulfur dioxide diffuses to the surface of the tube...

436

Identification and quantification of sulfur and nitrogen containing odorous compounds in wastewater  

Microsoft Academic Search

Sulfur and nitrogen containing malodorous compounds were identified and quantified in the samples taken from each step of sewage treatment employing aerated biofilters for advanced treatment. The sulfur compounds hydrogen sulfide, carbon disulfide, methyl mercaptan, dimethyl sulfide and dimethyl disulfide were detected by using GC-FPD with a headspac