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Sample records for process involving so2

  1. Delayed rectifier potassium channels are involved in SO2 derivative-induced hippocampal neuronal injury.

    Science.gov (United States)

    Li, Guangke; Sang, Nan

    2009-01-01

    Recent studies implicate the possible neurotoxicity of SO(2), however, its mechanisms remain unclear. In the present study, we investigated SO(2) derivative-induced effect on delayed rectifier potassium channels (I(K)) and cellular death/apoptosis in primary cultured hippocampal neurons. The results demonstrate that SO(2) derivatives (NaHSO(3) and Na(2)SO(3), 3:1M/M) effectively augmented I(K) and promoted the activation of delayed rectifier potassium channels. Also, SO(2) derivatives increased neuronal death percentage and contributed to the formation of DNA ladder in concentration-dependent manners. Interestingly, the neuronal death and DNA ladder formation, caused by SO(2) derivatives, could be attenuated by the delayed rectifier potassium channel blocker (tetraethylammonium, TEA), but not by the transient outward potassium channel blocker (4-aminopyridine, 4-AP). It implies that stimulating delayed rectifier potassium channels were involved in SO(2) derivative-caused hippocampal neuronal insults, and blocking these channels might be one of the possibly clinical treatment for SO(2)-caused neuronal dysfunction.

  2. Simplified model of SO2 removal from industrial gas in e-beam process

    International Nuclear Information System (INIS)

    Bouzyk, J.; Sowinski, M.

    1997-01-01

    The analysis of SO 2 and, on the part, NO x removal mechanism by e-beam process has been discussed. It is estimated that radiation contribution to SO 2 removal amounts to 40% while in the case of NO x it appears to reach about 70%. Taking into account the main reactions responsible for SO 2 oxidation as well as the assumption presented in our previous paper an algorithm has been developed to describe linear kinetics of the process. The principal assumption referred to depends on OH radical concentration to be nearly stable. The concept of an extended model of NO x /SO 2 removal has been presented and the literature data have been used to check the suggested model. On that basis the general idea has been proposed for controlling SO 2 /NO x removal which comprises both the simplified and extended pathway. (author)

  3. Reaction behavior of SO2 in the sintering process with flue gas recirculation.

    Science.gov (United States)

    Yu, Zhi-Yuan; Fan, Xiao-Hui; Gan, Min; Chen, Xu-Ling; Chen, Qiang; Huang, Yun-Song

    2016-07-01

    The primary goal of this paper is to reveal the reaction behavior of SO2 in the sinter zone, combustion zone, drying-preheating zone, and over-wet zone during flue gas recirculation (FGR) technique. The results showed that SO2 retention in the sinter zone was associated with free-CaO in the form of CaSO3/CaSO4, and the SO2 adsorption reached a maximum under 900ºC. SO2 in the flue gas came almost from the combustion zone. One reaction behavior was the oxidation of sulfur in the sintering mix when the temperature was between 800 and 1000ºC; the other behavior was the decomposition of sulfite/sulfate when the temperature was over 1000ºC. However, the SO2 adsorption in the sintering bed mainly occurred in the drying-preheating zone, adsorbed by CaCO3, Ca(OH)2, and CaO. When the SO2 adsorption reaction in the drying-preheating zone reached equilibrium, the excess SO2 gas continued to migrate to the over-wet zone and was then absorbed by Ca(OH)2 and H2O. The emission rising point of SO2 moved forward in combustion zone, and the concentration of SO2 emissions significantly increased in the case of flue gas recirculation (FGR) technique. Aiming for the reuse of the sensible heat and a reduction in exhaust gas emission, the FGR technique is proposed in the iron ore sintering process. When using the FGR technique, SO2 emission in exhaust gas gets changed. In practice, the application of the FGR technique in a sinter plant should be cooperative with the flue gas desulfurization (FGD) technique. Thus, it is necessary to study the influence of the FGR technique on SO2 emissions because it will directly influence the demand and design of the FGD system.

  4. miR398 and miR395 are involved in response to SO2 stress in Arabidopsis thaliana.

    Science.gov (United States)

    Li, Lihong; Yi, Huilan; Xue, Meizhao; Yi, Min

    2017-11-01

    Sulfur dioxide (SO 2 ) is a common air pollutant that has adverse effects on plants. MicroRNAs (miRNAs) are small noncoding RNA that play critical roles in plant development and stress response. In this study, we found that two miRNAs, miR398 and miR395, were differentially expressed in Arabidopsis shoots under SO 2 stress. The expression of miR398 was down-regulated, and the transcript levels of its target genes, Cu/Zn superoxide dismutases (CSD1 and CSD2), were increased during SO 2 exposure. The activity of superoxide dismutase (SOD), one of the major antioxidant enzymes, was enhanced with the increase in the CSD transcript level, suggesting an important role of miR398 in response to SO 2 -induced oxidative stress. Meanwhile, the expression of miR395 was increased, and the transcript levels of its target genes, ATP sulfurylases (APS3 and APS4) and a low-affinity sulfate transporter (SULTR2;1), were decreased in Arabidopsis shoots, showing that miR395 played important roles in the regulation of sulfate assimilation and translocation during SO 2 exposure. The content of glutathione (GSH), an important sulfur-containing antioxidant, was enhanced with the changes in sulfur metabolism in Arabidopsis shoots under SO 2 stress. These results showed that both miR398 and miR395 were involved in protecting plants from oxidative damage during SO 2 exposure. Many stress-responsive cis-elements were found in the promoter regions of MIR398 and MIR395, suggesting that these miRNAs might respond to various environmental conditions, including SO 2 stress. Overall, our study provides an insight into the regulatory roles of miRNAs in response to SO 2 stress in plants, and highlights the molecular mechanisms of plant adaptation to environmental stress.

  5. Removal of NOsub(x) and SO2 by the electron beam process

    International Nuclear Information System (INIS)

    Fuchs, P.; Roth, B.; Schwing, U.; Angele, H.; Gottstein, J.

    1988-01-01

    The electron beam process (EBP) is a dry method of flue gas purification for the simultaneous removal of NOsub(x) and SO 2 . The process has the potential to be used as a retrofit for existing coal fired power plants. Since the beginning of last year Badenwerk AG, in an association with other partners, has run a pilot plant incorporating this process in the new Unit No. 7 of the Rheinhafen-Dampfkraftwerk in Karlsruhe. The design and the operation as well as an account of test results and the experience accumulated during the operation of the facility are presented. (author)

  6. Radiation processes for the control of NOx/SO2 emissions

    International Nuclear Information System (INIS)

    Dickson, L.W.; Singh, A.

    1988-01-01

    This report provides a brief review of the use of radiation for the treatment of flue gases and identifies areas for additional research. Two different radiation-based processes have been developed for the removal of nitrogen oxides and sulphur dioxide from the flue gases of coal-fired boilers. In the technique developed by the Ebara Corporation and Japan Atomic Energy Research Institute, ammonia is injected prior to the irradiation step to enhance the process efficiency and to yield a solid ammonium sulphate - ammonium nitrate product that may be used as a fertilizer. The process developed by the Research-Cottrell Corporation uses electron-beam irradiation downstream of a lime spray dryer to remove nitrogen oxides and to enhance the sulphur dioxide removal efficiency. Both of these processes require large quantities of electron-beam power and are currently expected to be more expensive than other available sulphur dioxide emission control technologies. Present emission control regulations in North America do not require the high degree of nitrogen oxide removal provided by the radiation-based processes. Research into the radiolytic oxidation of nitrogen oxides and sulphur dioxide, the radiolytic oxidation of NO x /SO 2 on solid sorbents, and the radiolytic oxidation of NO x /SO 2 in electric fields may lead to the development of more economical radiation treatment processes for flue gases. 44 refs

  7. Thermal and energetic processing of astrophysical ice analogues rich in SO2

    Science.gov (United States)

    Kaňuchová, Z.; Boduch, Ph.; Domaracka, A.; Palumbo, M. E.; Rothard, H.; Strazzulla, G.

    2017-08-01

    Context. Sulfur is an abundant element in the cosmos and it is thus an important contributor to astrochemistry in the interstellar medium and in the solar system. Astronomical observations of the gas and of the solid phases in the dense interstellar/circumstellar regions have evidenced that sulfur is underabundant. The hypothesis to explain such a circumstance is that it is incorporated in some species in the solid phase (I.e. as frozen gases and/or refractory solids) and/or in the gas phase, which for different reasons have not been observed so far. Aims: Here we wish to give a contribution to the field by studying the chemistry induced by thermal and energetic processing of frozen mixtures of sulfur dioxide (one of the most abundant sulfur-bearing molecules observed so far) and water. Methods: We present the results of a series of laboratory experiments concerning thermal processing of different H2O:SO2 mixtures and ion bombardment (30 keV He+) of the same mixtures. We used in situ Fourier transform infrared (FTIR) spectroscopy to investigate the induced effects. Results: The results indicate that ionic species such as HSO, HSO, and S2O are easily produced. Energetic processing also produces SO3 polymers and a sulfurous refractory residue. Conclusions: The produced ionic species exhibit spectral features in a region that, in astronomical spectra of dense molecular clouds, is dominated by strong silicate absorption. However, such a dominant feature is associated with some spectral features, some of which have not yet been identified. We suggest adding the sulfur-bearing ionic species to the list of candidates to help explain some of those features. In addition, we suggest that once expelled in the gas phase by sublimation, due to the temperature increase, and/or by non-thermal erosion those species would constitute a class of molecular ions not detected so far. We also suggest that molecular sulfur-bearing ions could be present on the surfaces and/or in the

  8. Study on in-situ electrochemical impedance spectroscopy measurement of anodic reaction in SO_2 depolarized electrolysis process

    International Nuclear Information System (INIS)

    Xue Lulu; Zhang Ping; Chen Songzhe; Wang Laijun

    2014-01-01

    SO_2 depolarized electrolysis (SDE) is the pivotal reaction in hybrid sulfur process, one of the most promising approaches for mass hydrogen production without CO_2 emission. The net result of hybrid sulfur process is to split water into hydrogen and oxygen at a relatively low voltage, which will dramatically decrease the energy consumption for the production of hydrogen. The potential loss of SDE process could be separated into four components, i.e. reversible cell potential, anode overpotential, cathode overpotential and ohmic loss. So far, it has been identified that the total cell potential for the SO_2 depolarized electrolyzer is dominantly controlled by sulfuric acid concentration of the anolyte and electrolysis temperature of the electrolysis process. In this work, an in-situ Electrochemical Impedance Spectroscopy (EIS) measurement of the anodic SDE reaction was conducted. Results show that anodic overpotential is mainly resulted from the SO_2 oxidation reaction other than ohmic resistance or mass transfer limitation. This study extends the understanding to SDE process and gives suggestions for the further improvement of the SDE performance. (author)

  9. Rate-based modelling of combined SO2 removal and NH3 recycling integrated with an aqueous NH3-based CO2 capture process

    International Nuclear Information System (INIS)

    Li, Kangkang; Yu, Hai; Qi, Guojie; Feron, Paul; Tade, Moses; Yu, Jingwen; Wang, Shujuan

    2015-01-01

    Highlights: • A rigorous, rate-based model for an NH 3 –CO 2 –SO 2 –H 2 O system was developed. • Model predictions are in good agreement with pilot plant results. • >99.9% of SO 2 was captured and >99.9% of slipped ammonia was reused. • The process is highly adaptable to the variations of SO 2 /NH 3 level, temperatures. - Abstract: To reduce the costs of controlling emissions from coal-fired power stations, we propose an advanced and effective process of combined SO 2 removal and NH 3 recycling, which can be integrated with the aqueous NH 3 -based CO 2 capture process to simultaneously achieve SO 2 and CO 2 removal, NH 3 recycling and flue gas cooling in one process. A rigorous, rate-based model for an NH 3 –CO 2 –SO 2 –H 2 O system was developed and used to simulate the proposed process. The model was thermodynamically and kinetically validated by experimental results from the open literature and pilot-plant trials, respectively. Under typical flue gas conditions, the proposed process has SO 2 removal and NH 3 reuse efficiencies of >99.9%. The process is strongly adaptable to different scenarios such as high SO 2 levels in flue gas, high NH 3 levels from the CO 2 absorber and high flue gas temperatures, and has a low energy requirement. Because the process simplifies flue gas desulphurisation and resolves the problems of NH 3 loss and SO 2 removal, it could significantly reduce the cost of CO 2 and SO 2 capture by aqueous NH 3

  10. Novel separation process of gaseous mixture of SO2 and O2 with ionic liquid for hydrogen production in thermochemical sulfur-iodine water splitting cycle

    International Nuclear Information System (INIS)

    Kim, Chang Soo; Gong, Gyeong Taek; Yoo, Kye Sang; Kim, Honggon; Lee, Byoung Gwon; Ahn, Byoung Sung; Jung, Kwang Deog; Lee, Ki Yong; Song, Kwang Ho

    2007-01-01

    Sulfur-Iodine cycle is the most promising thermochemical cycle for water splitting to produce hydrogen which can replace the fossil fuels in the future. As a sub-cycle in the thermochemical Sulfur-Iodine water splitting cycle, sulfuric acid (H 2 SO 4 ) decomposes into oxygen (O 2 ) and sulfur dioxide (SO 2 ) which should be separated for the recycle of SO 2 into the sulfuric acid generation reaction (Bunsen Reaction). In this study, absorption and desorption process of SO 2 by ionic liquid which is useful for the recycle of SO 2 into sulfuric acid generation reaction after sulfuric acid decomposition in the thermochemical Sulfur-Iodine cycle is investigated. At first, the operability as an absorbent for the SO 2 absorption and desorption at high temperature without the volatilization of absorbents which is not suitable for the recycle of absorbent-free SO 2 after the absorption process. The temperature range of operability is determined by TGA and DTA analysis. Most of ionic liquids investigated are applicable at high temperature desorption without volatility around 300 deg. C except [BMIm] Cl, and [BMIm] OAc which show the decomposition of ionic liquids. To evaluate the capability of SO 2 absorption, each ionic liquid is located in the absorption tube and gaseous SO 2 is bubbled into the ionic liquid. During the bubbling, the weight of the system is measured and converted into the absorbed SO 2 amount at each temperature controlled by the heater. Saturated amounts of absorbed SO 2 by ionic liquids at 50 deg. C are presented. The effect of anions for the SO 2 absorption capability is shown in the order of Cl, OAc, MeSO 3 , BF 4 , MeSO 4 , PF 6 , and HSO 4 when they are combined with [BMIm] cation. [BMIm]Cl has the largest amount of SO 2 absorbed which can be the most promising absorbent; however, from the point of operability at high temperature which includes desorption process, [BMIm]Cl is vulnerable to high temperature around 250 deg. C based on the TGA

  11. Absorption of SO2 and NO through an integrative process with a cost-effective aqueous oxidant

    Directory of Open Access Journals (Sweden)

    Chelluboyana Vaishnava Raghunath

    2016-09-01

    Full Text Available Due to the substantial influence on the environment and health, there has been an intensifying environmental concern on sulfur dioxide (SO2 and nitrogen oxide (NO discharge to the atmosphere all over the world. Flue gas of coal-fired power stations is major leading source for the emission of SO2 and NO. Cost-effective and balanced technologies for the reduction of these pollutants from flue gas have become increasingly essential at the present time. The preliminary experimental attributes were retrieved in a batch scale agitating bubbling reactor for instantaneous absorption of SO2 and NO using aqueous oxidant. The prime conditions for instantaneous absorption examined were including absorbent concentration, reaction temperature, and pH in the fabricated flue gas system. Removal efficiencies of 99% for SO2 and 85% for NO were acquired, respectively under absorbent concentration 5 g/100 ml, reaction temperature 313 K, and pH 5.6.

  12. A Green Desulfurization Technique: Utilization of Flue Gas SO2 to Produce H2 via a Photoelectrochemical Process Based on Mo-Doped BiVO4

    Directory of Open Access Journals (Sweden)

    Jin Han

    2017-12-01

    Full Text Available A green photoelectrochemical (PEC process with simultaneous SO2 removal and H2 production has attracted an increasing attention. The proposed process uses flue gas SO2 to improve H2 production. The improvement of the efficiency of this process is necessary before it can become industrial viable. Herein, we reported a Mo modified BiVO4 photocatalysts for a simultaneous SO2 removal and H2 production. And the PEC performance could be significantly improved with doping and flue gas removal. The evolution rate of H2 and removal of SO2 could be enhanced by almost three times after Mo doping as compared with pristine BiVO4. The enhanced H2 production and SO2 removal is attributed to the improved bulk charge carrier transportation after Mo doping, and greatly enhanced oxidation reaction kinetics on the photoanode due to the formation of SO32− after SO2 absorption by the electrolyte. Due to the utilization of SO2 to improve the production of H2, the proposed PEC process may become a profitable desulfurization technique.

  13. A green desulfurization technique: utilization of flue gas SO2 to produce H2 via a photoelectrochemical process based on Mo-doped BiVO4

    Science.gov (United States)

    Han, Jin; Li, Kejian; Cheng, Hanyun; Zhang, Liwu

    2017-12-01

    A green photoelectrochemical (PEC) process with simultaneous SO2 removal and H2 production has attracted an increasing attention. The proposed process uses flue gas SO2 to improve H2 production. The improvement of the efficiency of this process is necessary before it can become industrial viable. Herein, we reported a Mo modified BiVO4 photocatalysts for a simultaneous SO2 removal and H2 production. And the PEC performance could be significantly improved with doping and flue gas removal. The evolution rate of H2 and removal of SO2 could be enhanced by almost 3 times after Mo doping as compared with pristine BiVO4. The enhanced H2 production and SO2 removal is attributed to the improved bulk charge carrier transportation after Mo doping, and greatly enhanced oxidation reaction kinetics on the photoanode due to the formation of SO32- after SO2 absorption by the electrolyte. Due to the utilization of SO2 to improve the production of H2, the proposed PEC process may become a profitable desulfurization technique.

  14. Mechanism of SO2 removal by carbon

    Science.gov (United States)

    Lizzio, Anthony A.; DeBarr, Joseph A.

    1997-01-01

    The reaction of SO2 with carbon (C) in the presence of O2 and H2O involves a series of reactions that leads to the formation of sulfuric acid as the final product. The rate-determining step in the overall process is the oxidation of SO2 to SO3. Three SO2 oxidation reactions are possible. Adsorbed SO2 (C−SO2) can react either with gas phase O2 or with adsorbed oxygen (C−O complex) to form sulfur trioxide (SO3), or gas phase SO2 can react directly with the C−O complex. In optimizing the SO2 removal capabilities of carbon, most studies only assume a given mechanism for SO2 adsorption and conversion to H2SO4 to be operable. The appropriate SO2 oxidation step and role of the C−O complex in this mechanism remain to be determined. The ultimate goal of this study was to prepare activated char from Illinois coal with optimal properties for low-temperature (80−150°C) removal of sulfur dioxide from coal combustion flue gas. The SO2 adsorption capacity of activated char was found to be inversely proportional to the amount of oxygen adsorbed on its surface. A temperature-programmed desorption technique was developed to titrate those sites responsible for adsorption of SO2 and conversion to H2SO4. On the basis of these results, a mechanism for SO2 removal by carbon was proposed. The derived rate expression showed SO2 adsorption to be dependent only on the fundamental rate constant and concentration of carbon atoms designated as free sites. Recent studies indicate a similar relationship exists between the rate of carbon gasification (in CO2 or H2O) and the number of reactive sites as determined by transient kinetics experiments. Utilizing the concept of active or free sites, it was possible to produce a char from Illinois coal having an SO2 adsorption capacity surpassing that of a commercial catalytic activated carbon.

  15. A feasible process for simultaneous removal of CO2, SO2 and NOx in the cement industry by NH3 scrubbing

    International Nuclear Information System (INIS)

    Dong, Ruifeng; Lu, Hongfang; Yu, Yunsong; Zhang, Zaoxiao

    2012-01-01

    Highlights: ► Simultaneous removal of CO 2 , SO 2 and NO x is realized by NH 3 scrubbing with NaClO 2 . ► The crystallization process of NH 4 HCO 3 is employed instead of CO 2 regeneration. ► Energy consumption reduces hugely while CO 2 removal rate remains higher than 90%. ► Exergy calculation reveals that a higher thermodynamic perfection degree is achieved. -- Abstract: With the rapid economic and industrial development, the concentration of carbon dioxide in the atmosphere is increasing enormously, which has greatly affected the global climate and human living environment. At present, a lot of technologies have been applied to CO 2 removal in fossil fuel-fired power plants, which are one of the main CO 2 emission sources. But few researches have been done in the cement industry, which is the third largest CO 2 emission source. There is no mature technology of CO 2 removal in cement industry mentioned before. This paper proposes a feasible process for simultaneous removal of CO 2 , SO 2 and NO x in the cement industry by NH 3 scrubbing. As there is no ready steam source for the regeneration of CO 2 -rich loading solvent after absorption, a process with the final product of ammonium bicarbonate is developed. With the oxidative additive of NaClO 2 added in the aqueous ammonium absorbent, the simultaneous removal of CO 2 , SO 2 and NO x is feasible by NH 3 scrubbing. The products of the process are mainly ammonium bicarbonate, ammonium sulfate and ammonium nitrate, which are all good fertilizers for crops and plants. The crystallization of NH 4 HCO 3 is easier for storage and transportation than that for liquid carbon dioxide, which becomes more stable when dicyandiamide (DCD) is added. The thermodynamic analysis proves that the proposed process has the advantages of energy conservation and high thermodynamic perfection degree compared with the traditional ones.

  16. An innovative process for simultaneous removal of CO2 and SO2 from flue gas of a power plant by energy integration

    International Nuclear Information System (INIS)

    Yu, Y.S.; Li, Y.; Li, Q.; Jiang, J.; Zhang, Z.X.

    2009-01-01

    With the fast development of the society, the amount of carbon dioxide has been increased enormously in the atmosphere all over the world, which has already endangered the survival of human being. More and more people or organizations are studying new technologies to reduce the cost of capturing CO 2 . The recovery and sequestration of CO 2 from flue gas of the power plant is regarded as a feasible way to mitigate the greenhouse gas emissions. Therefore, the process of recovering carbon dioxide by chemical absorption with monoethanolamine (MEA) in industry was emphatically described in this paper. Based on energy integration, a coupled process was proposed which included MEA absorption of CO 2 and SO 2 , and the heat recovery from the flue gas's waste heat recovery unit and compressor inter-stage cooling unit. Compared the innovative process with an original process, 9% of thermal energy could be reduced in the new flowsheet. Meanwhile decarbonization and desulphurization could be carried on in the absorber simultaneously without the usual wet flue gas desulphurization (FGD) system. An exergy analysis model was established and validated by the literature data with a deviation less than 5.40%. The exergy results indicated that the exergy loss of the improved process was 15.48-20.75% less than that of the original one, which proved that the innovative process was reasonable and effective from the perspective of energy utilization.

  17. The US SO2 Auction

    DEFF Research Database (Denmark)

    Svendsen, Gert Tinggaard; Christensen, Jan Lien

    1998-01-01

    An annual discriminative and revenue-neutral auction is linked to the new Acid Rain Program which allows electric utilities all over the US to trade SO2 emission permits. This innovative SO2 auction distributes 2% of the permits in circulation and takes place at the Chicago Board of Trade. Early...

  18. Atmospheric processes affecting the separation of volcanic ash and SO2 in volcanic eruptions: inferences from the May 2011 Grímsvötn eruption

    Directory of Open Access Journals (Sweden)

    F. Prata

    2017-09-01

    Full Text Available The separation of volcanic ash and sulfur dioxide (SO2 gas is sometimes observed during volcanic eruptions. The exact conditions under which separation occurs are not fully understood but the phenomenon is of importance because of the effects volcanic emissions have on aviation, on the environment, and on the earth's radiation balance. The eruption of Grímsvötn, a subglacial volcano under the Vatnajökull glacier in Iceland during 21–28 May 2011 produced one of the most spectacular examples of ash and SO2 separation, which led to errors in the forecasting of ash in the atmosphere over northern Europe. Satellite data from several sources coupled with meteorological wind data and photographic evidence suggest that the eruption column was unable to sustain itself, resulting in a large deposition of ash, which left a low-level ash-rich atmospheric plume moving southwards and then eastwards towards the southern Scandinavian coast and a high-level predominantly SO2 plume travelling northwards and then spreading eastwards and westwards. Here we provide observational and modelling perspectives on the separation of ash and SO2 and present quantitative estimates of the masses of ash and SO2 that erupted, the directions of transport, and the likely impacts. We hypothesise that a partial column collapse or sloughing fed with ash from pyroclastic density currents (PDCs occurred during the early stage of the eruption, leading to an ash-laden gravity intrusion that was swept southwards, separated from the main column. Our model suggests that water-mediated aggregation caused enhanced ash removal because of the plentiful supply of source water from melted glacial ice and from entrained atmospheric water. The analysis also suggests that ash and SO2 should be treated with separate source terms, leading to improvements in forecasting the movement of both types of emissions.

  19. Atmospheric processes affecting the separation of volcanic ash and SO2 in volcanic eruptions: inferences from the May 2011 Grímsvötn eruption

    Science.gov (United States)

    Prata, Fred; Woodhouse, Mark; Huppert, Herbert E.; Prata, Andrew; Thordarson, Thor; Carn, Simon

    2017-09-01

    The separation of volcanic ash and sulfur dioxide (SO2) gas is sometimes observed during volcanic eruptions. The exact conditions under which separation occurs are not fully understood but the phenomenon is of importance because of the effects volcanic emissions have on aviation, on the environment, and on the earth's radiation balance. The eruption of Grímsvötn, a subglacial volcano under the Vatnajökull glacier in Iceland during 21-28 May 2011 produced one of the most spectacular examples of ash and SO2 separation, which led to errors in the forecasting of ash in the atmosphere over northern Europe. Satellite data from several sources coupled with meteorological wind data and photographic evidence suggest that the eruption column was unable to sustain itself, resulting in a large deposition of ash, which left a low-level ash-rich atmospheric plume moving southwards and then eastwards towards the southern Scandinavian coast and a high-level predominantly SO2 plume travelling northwards and then spreading eastwards and westwards. Here we provide observational and modelling perspectives on the separation of ash and SO2 and present quantitative estimates of the masses of ash and SO2 that erupted, the directions of transport, and the likely impacts. We hypothesise that a partial column collapse or sloughing fed with ash from pyroclastic density currents (PDCs) occurred during the early stage of the eruption, leading to an ash-laden gravity intrusion that was swept southwards, separated from the main column. Our model suggests that water-mediated aggregation caused enhanced ash removal because of the plentiful supply of source water from melted glacial ice and from entrained atmospheric water. The analysis also suggests that ash and SO2 should be treated with separate source terms, leading to improvements in forecasting the movement of both types of emissions.

  20. Influence of cathode on the electro-generation of peroxydisulfuric acid oxidant and its application for effective removal of SO_2 by room temperature electro-scrubbing process

    International Nuclear Information System (INIS)

    Balaji, Subramanian; Muthuraman, Govindan; Moon, Il Shik

    2015-01-01

    Highlights: • Electrolytic production of peroxydisulfuric acid (PDSA) with BDD anode. • PDSA yield enhanced by proper selection of cathode material. • Electro-scrubbing of SO_2 in presence of PDSA monitored by online FTIR analyzer. • 100% SO_2 removal was achieved for 25 ppm and 50 ppm in less than 10 min. - Abstract: Peroxydisulfuric acid oxidant (H_2S_2O_8) was electro-generated using boron doped diamond (BDD) anode in an undivided electrolytic cell under the optimized conditions and used for the oxidative removal of gaseous SO_2. The influence of the nature of cathode material on the formation yield of H_2S_2O_8 was investigated with Ti, Pt, Zr and DSA electrodes in a flow type electrolytic cell under batch recirculation mode. Among the various cathodes employed Ti exhibited a good performance and the formation yield was nearly doubled (0.19 M) compared to the reported value of 0.07 M. The optimization of electrode area ratio between the anode and cathode brought out the fact that for nearly 8 times smaller Ti cathode (8.75:1) the achieved yield was ∼65% higher than the 1:1 ratio of anode and cathode. The highest concentration of 6.8% (0.48 M) H_2S_2O_8 was seen for 35 cm"2 BDD anode with 4 cm"2 Ti at 20 °C with the measured redox potential value of +1200 mV. The oxidative removal of SO_2 in an electro-scrubbing column attached to the online production of peroxydisulfuric acid under the optimized conditions of cell parameters shows that SO_2 removal efficiency was nearly 100% for 25 and 50 ppm inlet concentrations and 96% for 100 ppm at the room temperature of 25 °C.

  1. Mechanisms of radical removal by SO2

    DEFF Research Database (Denmark)

    Rasmussen, Christian Lund; Glarborg, Peter; Marshall, Paul

    2007-01-01

    It is well established from experiments in premixed, laminar flames, jet-stirred reactors, flow reactors, and batch reactors that SO2 acts to catalyze hydrogen atom removal at stoichiometric and reducing conditions. However, the commonly accepted mechanism for radical removal, SO2 + H......(+M) reversible arrow HOSO(+M), HOSO + H/OH reversible arrow SO2 + H-2/H2O, has been challenged by recent theoretical and experimental results. Based on ab initio calculations for key reactions, we update the kinetic model for this chemistry and re-examine the mechanism of fuel/SO2 interactions. We find...... that the interaction of SO, with the radical pool is more complex than previously assumed, involving HOSO and SO, as well as, at high temperatures also HSO, SH, and S. The revised mechanism with a high rate constant for H + SO2 recombination and with SO + H2O, rather than SO2 + H-2, as major products of the HOSO + H...

  2. Sulfur Dioxide (SO2) Emissions From Onshore Natural Gas Processing for Which Construction, Reconstruction, or Modification Commenced After January 20, 1984, and on or Before August 23, 2011: New Source Performance Standards (NSPS)

    Science.gov (United States)

    Learn more about the NSPS regulation for SO2 emissions from onshore natural gas processing by reading the rule history, rule summary, federal register notices and the code of federal regulations subpart

  3. SO2 - An indirect source of energy

    DEFF Research Database (Denmark)

    Kriek, R.J.; Van Ravenswaay, J.P.; Potgieter, M.

    2013-01-01

    -related processes 12.8 Mt. As a well-known gaseous pollutant, SO2 is not per se known as a source of energy. However, in the presence of water SO2 can be electro-oxidized at the anode of an electrolyser to produce hydrogen ions, which in turn can be reduced at the cathode of the electrolyser to produce hydrogen gas......Global sulphur dioxide (SO2) emissions peaked around the mid- 1970s, after which they declined. However, with the growth of specifically China, emissions are on the rise again. In 2008, global anthropogenic SO2 emissions totalled 127 Mt, with energy production accounting for 63.2 Mt and metal....... Gaseous emissions of SO2 can therefore be cleaned up with the simultaneous production of hydrogen, an energy store or carrier, which provides an economic offset to the overall cost of this potential remediation process. This process forms part of the Hybrid Sulfur (HyS) cycle as well as the once...

  4. Considerations on abatement of SO2 pollution

    International Nuclear Information System (INIS)

    Ataman, E.

    1992-01-01

    The paper brings into focus the problems related to the SO 2 environmental pollution, to the emission standards, stress being laid on the possibilities of SO 2 emissions reduction resulting from the man-made stationary sources. A comparative estimation is made concerning the necessary investments for the desulfurization plants in accordance with the process employed and with the size of the boiler, as well as, of the operating costs brought about by desulfurization. The paper concludes with the prospects of flue gas reduction in thermal power plants. (author). 5 tabs., 21 refs

  5. Future prices and market for SO2 allowances

    International Nuclear Information System (INIS)

    Sanghi, A.; Joseph, A.; Michael, K.; Munro, W.; Wang, J.

    1993-01-01

    The expected price of SO 2 emission allowances is an important issue in energy and integrated resource planning activities. For example, the expected price of SO 2 allowances in needed in order to evaluate alternative strategies for meeting SO 2 provisions of the Clean Air Act Amendments of 1990. In addition, the expected SO 2 allowance price is important to state public utility regulators who must provide guidance on rate-making issues regarding utility compliance plans which involve allowance trading and direct investment of SO 2 control technologies. Last but not the least, the expected SO 2 allowance price is an important determinant of the future market for natural gas and low sulfur coal. The paper develops estimates of SO 2 allowance prices over time by constructing national supply and demand curves for SO 2 reductions. Both the supply and demand for SO 2 reductions are based on an analysis of the sulfur content of fuels burned in 1990 by utilities throughout the United States; and on assumptions about plant retirements, the rate of new capacity growth, the types of new and replacement plants constructed, the costs of SO 2 reduction measures and legislation by midwest states to maintain the use of high sulfur coal to protect local jobs. The paper shows that SO 2 allowance prices will peak around the year 2000 at about $500 per ton, and will eventually fall to zero by about the year 2020. A sensitivity analysis indicates that the price of SO 2 allowances is relatively insensitive to assumptions regarding the availability of natural gas or energy demand growth. However, SO 2 allowance prices tend to be quite sensitive to assumptions regarding regulations which may force early retirement of existing power plants and possible legislation which may reduce CO 2 emissions

  6. Effects of SO2 and sulfite on stromal metabolism

    International Nuclear Information System (INIS)

    Anderson, L.E.; Muschinek, G.; Marques, I.

    1986-01-01

    SO 2 appears to have multiple effects on chloroplast stromal metabolism. What is unique about metabolism in the chloroplast is reductive modulation of enzyme activity. The evidence summarized here implicates both the components of the modulation process and the light modulated enzymes and ribulosebisphosphate carboxylase in SO 2 -sensitivity. Interference with electron transport, acidification of the stroma, and depletion of phosphates will further complicate metabolism in the photosynthesizing chloroplast when sensitive plants are exposed to SO 2 . 35 refs., 6 figs

  7. DHA involvement in neurotransmission process

    Directory of Open Access Journals (Sweden)

    Vancassel Sylvie

    2007-05-01

    Full Text Available The very high enrichment of the nervous system in the polyunsaturated fatty acids, arachidonic (AA, 20: 4n-6 and docosahexaenoic acids (DHA, 22: 6n-3, is dependant of the dietary availability of their respective precursors, linoleic (18: 2n-6 and_-linolenic acids (18: 3n-3. Inadequate amounts of DHA in brain membranes have been linked to a wide variety of abnormalities ranging from visual acuity and learning irregularities, to psychopathologies. However, the molecular mechanisms involved remain unknown. Several years ago, we hypothesized that a modification of DHA contents of neuronal membranes by dietary modulation could change the neurotransmission function and then underlie inappropriate behavioural response. We showed that, in parallel to a severe loss of brain DHA concomitant to a compensatory substitution by 22:5n-6, the dietary lack of α-linolenic acid during development induced important changes in the release of neurotransmitters (dopamine, serotonin, acetylcholine in cerebral areas specifically involved in learning, memory and reward processes. Data suggested alteration of presynaptic storage process and dysregulations of reciprocal functional interactions between monoaminergic and cholinergic pathways. Moreover, we showed that recovery of these neurochemical changes was possible when the deficient diet was switched to a diet balanced in n-3 and n-6 PUFA before weaning. The next step is to understand the mechanism involved. Particularly, we focus on the study of the metabolic cooperation between the endothelial cell, the astrocyte and the neuron which regulate synaptic transmission.These works could contribute to the understanding of the link between some neuropsychiatric disorders and the metabolism of n-3 PUFA, through their action on neurotransmission.

  8. Understanding SO2 Capture by Ionic Liquids.

    Science.gov (United States)

    Mondal, Anirban; Balasubramanian, Sundaram

    2016-05-19

    Ionic liquids have generated interest for efficient SO2 absorption due to their low vapor pressure and versatility. In this work, a systematic investigation of the structure, thermodynamics, and dynamics of SO2 absorption by ionic liquids has been carried out through quantum chemical calculations and molecular dynamics (MD) simulations. MP2 level calculations of several ion pairs complexed with SO2 reveal its preferential interaction with the anion. Results of condensed phase MD simulations of SO2-IL mixtures manifested the essential role of both cations and anions in the solvation of SO2, where the solute is surrounded by the "cage" formed by the cations (primarily its alkyl tail) through dispersion interactions. These structural effects of gas absorption are substantiated by calculated Gibbs free energy of solvation; the dissolution is demonstrated to be enthalpy driven. The entropic loss of SO2 absorption in ionic liquids with a larger anion such as [NTf2](-) has been quantified and has been attributed to the conformational restriction of the anion imposed by its interaction with SO2. SO2 loading IL decreases its shear viscosity and enhances the electrical conductivity. This systematic study provides a molecular level understanding which can aid the design of task-specific ILs as electrolytes for efficient SO2 absorption.

  9. SO2 emission scenarios of eastern China

    International Nuclear Information System (INIS)

    Qi, L.; Hao, J.; Lu, M.

    1995-01-01

    Under the National Key Project in Eighth Five-year Plan, a study was carried out on forecasting SO 2 emission from coal combustion in China, with a special emphasis on the eastern area. 3 scenarios, i.e. 'Optimistic', 'Pessimistic' and 'Business as Usual' scenarios were developed trying to cover changing scale of coal consumption and SO 2 emission from 1990 to 2020. A 'Top-down' approach was employed, and coal consumption elasticity was defined to project future economic growth and coal consumption. SO 2 emission scenarios were outlined, based on coal consumption, estimated sulfur content level and prospective SO 2 control situation. Emission level for each 1 degree longitude x 1 degree latitude grid cell within eastern China was also estimated to show geographical distribution of SO 2 sources. The results show that SO 2 emission in China will increase rapidly, if the current situation for energy saving and SO 2 control is maintained without improvement; measures enhanced reasonably with economic growth could stop further increase of emission by 2010. Realization of more encouraging objective to keep emission at even below 1990 level needs, however, more stringent options. The share of eastern China in the country's total emission would increase until 2000, while the general changing tendency would principally follow the scenarios of the whole country. 4 refs., 5 figs., 1 tab

  10. Emission of SO2 from Cement Production

    DEFF Research Database (Denmark)

    Hu, Guilin

    2007-01-01

    Ph. D. afhandlingen omhandler problemstillinger af speciel relevans for cementproduktion med lave emissioner af svolvdioxid. Afhandlingen omfatter dels pyritoxidation – dvs. dannelse af SO2, dels direkte sulfatering af kalksten – dvs. absorptionen af SO2 på CaCO3 under oxiderende betingelser i...... temperaturområdet 723–973 K. De to parallelle reaktioner er tilsammen ansvarlige for hovedparten af SO2 emissionen fra cementproduktion. Et omfattende litteraturstudium viser at pyrit i en oxidativ atmosfære kan blive oxideret direkte eller via en to–trinsproces hvor der først dannes pyrrhotit. Den præcise...... for SO2 absorption på kalksten i en cyklonforvarmer. Initialkinetikken er således op til 100 gange hurtigere end tidligere målinger præsenteret i litteraturen. Sulfaterinshastigheden falder hurtigt med omsætningsgraden af kalkstenen sandsynligvis på grund af dækning af kalkstensoverfladen med...

  11. Implementing SO2 Emissions in China

    International Nuclear Information System (INIS)

    Schreifels, J.; Yang, J.

    2003-01-01

    Over the past 10 years, the Chinese State Environmental Protection Administration (SEPA) has actively investigated the potential to use emission trading to reduce sulphur dioxide (SO2) emissions from electricity generators and industrial sources. In 1999, SEPA partnered with the U.S. Environmental Protection Agency (U.S. EPA) to cooperate on a study to assess the feasibility of implementing SO2 emission trading in China. SEPA has also pursued emission trading pilot projects in several cities and provinces. The authors, using information from the feasibility study and pilot projects, introduce the circumstances necessary for SO2 emission trading in China, outline the experience to date, and analyse implementation opportunities and barriers in China. The contents of the paper are: (1) SO2 emission control policies in China; (2) institutional requirements and the basis for introducing SO2 emission trading in China; (3) case studies of emission trading in China; (4) opportunities and barriers to implementing emission trading in China; (5) recommendations to transition from pilot projects to a nationwide SO2 emission trading program; and (6) conclusions and suggestions

  12. Imaging volcanic CO2 and SO2

    Science.gov (United States)

    Gabrieli, A.; Wright, R.; Lucey, P. G.; Porter, J. N.

    2017-12-01

    Detecting and quantifying volcanic carbon dioxide (CO2) and sulfur dioxide (SO2) emissions is of relevance to volcanologists. Changes in the amount and composition of gases that volcanoes emit are related to subsurface magma movements and the probability of eruptions. Volcanic gases and related acidic aerosols are also an important atmospheric pollution source that create environmental health hazards for people, animals, plants, and infrastructures. For these reasons, it is important to measure emissions from volcanic plumes during both day and night. We present image measurements of the volcanic plume at Kīlauea volcano, HI, and flux derivation, using a newly developed 8-14 um hyperspectral imaging spectrometer, the Thermal Hyperspectral Imager (THI). THI is capable of acquiring images of the scene it views from which spectra can be derived from each pixel. Each spectrum contains 50 wavelength samples between 8 and 14 um where CO2 and SO2 volcanic gases have diagnostic absorption/emission features respectively at 8.6 and 14 um. Plume radiance measurements were carried out both during the day and the night by using both the lava lake in the Halema'uma'u crater as a hot source and the sky as a cold background to detect respectively the spectral signatures of volcanic CO2 and SO2 gases. CO2 and SO2 path-concentrations were then obtained from the spectral radiance measurements using a new Partial Least Squares Regression (PLSR)-based inversion algorithm, which was developed as part of this project. Volcanic emission fluxes were determined by combining the path measurements with wind observations, derived directly from the images. Several hours long time-series of volcanic emission fluxes will be presented and the SO2 conversion rates into aerosols will be discussed. The new imaging and inversion technique, discussed here, are novel allowing for continuous CO2 and SO2 plume mapping during both day and night.

  13. DHA involvement in neurotransmission process

    OpenAIRE

    Vancassel Sylvie; Aïd Sabah; Denis Isabelle; Guesnet Philippe; Lavialle Monique

    2007-01-01

    The very high enrichment of the nervous system in the polyunsaturated fatty acids, arachidonic (AA, 20: 4n-6) and docosahexaenoic acids (DHA, 22: 6n-3), is dependant of the dietary availability of their respective precursors, linoleic (18: 2n-6) and_-linolenic acids (18: 3n-3). Inadequate amounts of DHA in brain membranes have been linked to a wide variety of abnormalities ranging from visual acuity and learning irregularities, to psychopathologies. However, the molecular mechanisms involved ...

  14. Supported polytertiary amines: highly efficient and selective SO2 adsorbents.

    Science.gov (United States)

    Tailor, Ritesh; Abboud, Mohamed; Sayari, Abdelhamid

    2014-01-01

    Tertiary amine containing poly(propyleneimine) second (G2) and third (G3) generation dendrimers as well as polyethyleneimine (PEI) were developed for the selective removal of SO2. N-Alkylation of primary and secondary amines into tertiary amines was confirmed by FTIR and NMR analysis. Such modified polyamines were impregnated on two nanoporous supports, namely, SBA-15PL silica with platelet morphology and ethanol-extracted pore-expanded MCM-41 (PME) composite. In the presence of 0.1% SO2/N2 at 23 °C, the uptake of modified PEI, G2, and G3 supported on SBA-15PL was 2.07, 2.35, and 1.71 mmol/g, respectively; corresponding to SO2/N ratios of 0.22, 0.4, and 0.3. Under the same conditions, the SO2 adsorption capacity of PME-supported modified PEI and G3 was significantly higher, reaching 4.68 and 4.34 mmol/g, corresponding to SO2/N ratios of 0.41 and 0.82, respectively. The working SO2 adsorption capacity decreased with increasing temperature, reflecting the exothermic nature of the process. The adsorption capacity of these materials was enhanced dramatically in the presence of humidity in the gas mixture. FTIR data before SO2 adsorption and after adsorption and regeneration did not indicate any change in the materials. Nonetheless, the SO2 working capacity decreased in consecutive adsorption/regeneration cycles due to evaporation of impregnated polyamines, rather than actual deactivation. FTIR and (13)C and (15)N CP-MAS NMR of fresh and SO2 adsorbed modified G3 on PME confirmed the formation of a complexation adduct.

  15. Hard target LIDAR calibration for SO2

    CSIR Research Space (South Africa)

    Du Plessis, A

    2006-01-01

    Full Text Available calibration for SO2 A du Plessis, DE Roberts CSIR National Laser Centre, Pretoria Slide 2 © CSIR 2006 www.csir.co.za Project background • Las-R-MAP: Laser – Remote – Measurement of Atmospheric Pollutants • Mobile laser system....csir.co.za Hard target backscatter ∫ = − R dRRn p e R RcE RS 0 )(2 2 )()( λσ λ β S R Slide 10 © CSIR 2006 www.csir.co.za Las-R-MAP hardware: laser system Slide 11 © CSIR 2006 www.csir.co.za Las-R...

  16. User involvement in the innovation process

    DEFF Research Database (Denmark)

    Christensen, Dan Saugstrup

    2008-01-01

    User involvement in the innovation process is not a new phenomenon. However, combined with the growing individualisation of demand and with highly competitive and dynamic environments, user involvement in the innovation process and thereby in the design, development, and manufacturing process, can...... nevertheless provide a competitive advantage. This is the case as an intensified user involvement in the innovation process potentially results in a more comprehensive understanding of the user needs and requirements and the context within which these are required, and thereby provides the possibility...... of developing better and more suitable products. The theoretical framework of this thesis is based on user involvement in the innovation process and how user involvement in the innovation process can be deployed in relation to deriving and colleting user needs and requirements, and thereby serves...

  17. Laboratory study on new particle formation from the reaction OH + SO2: influence of experimental conditions, H2O vapour, NH3 and the amine tert-butylamine on the overall process

    Directory of Open Access Journals (Sweden)

    J. Curtius

    2010-08-01

    Full Text Available Nucleation experiments starting from the reaction of OH radicals with SO2 have been performed in the IfT-LFT flow tube under atmospheric conditions at 293±0.5 K for a relative humidity of 13–61%. The presence of different additives (H2, CO, 1,3,5-trimethylbenzene for adjusting the OH radical concentration and resulting OH levels in the range (4–300 ×105 molecule cm−3 did not influence the nucleation process itself. The number of detected particles as well as the threshold H2SO4 concentration needed for nucleation was found to be strongly dependent on the counting efficiency of the used counting devices. High-sensitivity particle counters allowed the measurement of freshly nucleated particles with diameters down to about 1.5 nm. A parameterization of the experimental data was developed using power law equations for H2SO4 and H2O vapour. The exponent for H2SO4 from different measurement series was in the range of 1.7–2.1 being in good agreement with those arising from analysis of nucleation events in the atmosphere. For increasing relative humidity, an increase of the particle number was observed. The exponent for H2O vapour was found to be 3.1 representing an upper limit. Addition of 1.2×1011 molecule cm−3 or 1.2×1012 molecule cm−3 of NH3 (range of atmospheric NH3 peak concentrations revealed that NH3 has a measureable, promoting effect on the nucleation rate under these conditions. The promoting effect was found to be more pronounced for relatively dry conditions, i.e. a rise of the particle number by 1–2 orders of magnitude at RH = 13% and only by a factor of 2–5 at RH = 47% (NH3 addition: 1.2×1012 molecule cm−3. Using the amine tert-butylamine instead of NH3, the enhancing impact of the base for nucleation and particle growth appears to be stronger. Tert-butylamine addition of about 1010 molecule cm−3 at RH = 13% enhances particle formation by about two orders of magnitude, while for NH3 only a small or negligible

  18. SO2 sorption on fresh and aged SOx traps

    International Nuclear Information System (INIS)

    Limousy, L.; Mahzoul, H.; Brilhac, J.F.; Gilot, P.; Garin, F.; Maire, G.

    2003-01-01

    This study has an important impact on gasoline engine-pollution control working under lean conditions. While NO x trap systems can remove NO x under an oxidative atmosphere, they are poisoned by SO x present in the exhaust gases. In order to protect NO x traps, an upstream SO x trap has to be used. SO 2 adsorption was studied in the presence of water and oxygen. Model and commercial catalysts were tested between 300 and 700C. In order to assign the TPD peaks, the decomposition of commercial sulphates was studied versus the temperature. Adsorption capacity is not sensitive to oxygen and SO 2 concentrations but is strongly related to barium content. Cerium content is not a key parameter for SO 2 adsorption capacity in the presence of oxygen. XPS analysis allowed us to differentiate between all the species formed during the adsorption process. When the catalysts are aged, specific surface area decreases as well as adsorption capacity

  19. Combined CO/CH4 oxidation tests over Pd/Co3O4 monolithic catalyst. Effects of high reaction temperature and SO2 exposure on the deactivation process

    International Nuclear Information System (INIS)

    Liotta, L.F.; Venezia, A.M.; Di Carlo, G.; Pantaleo, G.; Deganello, G.; Merlone Borla, E.; Pidria, M.

    2007-01-01

    CO and CH 4 combined oxidation tests were performed over a Pd (70 g/ft 3 )/Co 3 O 4 monolithic catalyst in conditions of GHSV = 100,000 h -1 and feed composition close to that of emission from bi-fuel vehicles. The effect of SO 2 (5 ppm) on CO and CH 4 oxidation activity under lean condition (λ 2) was investigated. The presence of sulphur strongly deactivated the catalyst towards methane oxidation, while the poisoning effect was less drastic in the oxidation of CO. Saturation of the Pd/Co 3 O 4 catalytic sites via chemisorbed SO 3 and/or sulphates occurred upon exposure to SO 2 . A treatment of regeneration to remove sulphate species was attempted by performing a heating/cooling cycle up to 900 C in oxidizing atmosphere. Decomposition of PdO and Co 3 O 4 phases at high temperature, above 750 C, was observed. Moreover, sintering of Pd 0 and PdO particles along with of CoO crystallites takes place. (author)

  20. Getting Involved in the IEP Process

    Science.gov (United States)

    Kowalski, Ellen; Lieberman, Lauren J.; Daggett, Sara

    2006-01-01

    Although, in many districts, physical educators are integral members of the Individualized Education Program (designed for students with disabilities such as Down syndrome and autism), in other districts, physical educators are only partially involved in the process or are not given the opportunity to be involved at all. However, the physical…

  1. Evaluation of SO2 compliance strategies at Virginia Power

    International Nuclear Information System (INIS)

    Presley, J.V.; Tomlinson, M.; Ulmer, R.H.

    1992-01-01

    This paper will address the process undertaken by Virginia Power to assess SO 2 control strategies available for complying with the Revised Clean Air Act. In April 1990, in anticipation of the passage of an amended Clean Air Act, Virginia Power assembled a task force of personnel from a wide cross section of the company. This task force was given the responsibility of providing an assessment of the requirements of the new legislation, evaluating compliance alternatives and providing recommendations for implementation of the least cost alternative. Twenty-four potential SO 2 compliance options were identified for evaluation for Phase I. These options included various levels of coal switching, gas co-firing and scrubbing. Each option was evaluated and compared to a base case which assumed no SO 2 control. As a result of our evaluations, the lowest cost and least risk approach to Phase I SO 2 compliance for Virginia Power appears to be to construct a scrubber for one unit (550 MW g ) at our Mt. Storm Power Station

  2. Spin versus helicity in processes involving transversity

    CERN Document Server

    Mekhfi, Mustapha

    2011-01-01

    We construct the spin formalism in order to deal in a direct and natural way with processes involving transversity which are now of increasing popularity. The helicity formalism which is more appropriate for collision processes of definite helicity has been so far used also to manage processes with transversity, but at the price of computing numerous helicity amplitudes generally involving unnecessary kinematical variables.In a second step we work out the correspondence between both formalisms and retrieve in another way all results of the helicity formalism but in simpler forms.We then compute certain processes for comparison.A special process:the quark dipole magnetic moment is shown to be exclusively treated within the spin formalism as it is directly related to the transverse spin of the quark inside the baryon.

  3. EFFECT OF TEMPERATURE ON SO2 ABSORPTION

    OpenAIRE

    Mazlumoglu, Hayrunnisa; Gülaboğlu, Mustafa Şahin

    2017-01-01

    There has been an increase in energy requirements linked to the advances in technology. For energy production, the most common method is the use of fossil fuels to obtain energy by processing in thermal power stations (DPT, 2001). For waste gas treatments which reduce the damage to the environment caused by power stations, the wet flue gas desulfurization process is commonly used. Mardin-Mazıdağı phosphate rock was investigated for use in the wet flue gas desulfurization method and with this ...

  4. Heterogeneous Reaction of SO2 on Manganese Oxides: the Effect of Crystal Structure and Relative Humidity.

    Science.gov (United States)

    Yang, Weiwei; Zhang, Jianghao; Ma, Qingxin; Zhao, Yan; Liu, Yongchun; He, Hong

    2017-07-03

    Manganese oxides from anthropogenic sources can promote the formation of sulfate through catalytic oxidation of SO 2 . In this study, the kinetics of SO 2 reactions on MnO 2 with different morphologies (α, β, γ and δ) was investigated using flow tube reactor and in situ Diffuse Reflectance Infrared Fourier Transform Spectroscopy (DRIFTS). Under dry conditions, the reactivity towards SO 2 uptake was highest on δ-MnO 2 but lowest on β-MnO 2 , with a geometric uptake coefficient (γ obs ) of (2.42 ± 0.13) ×10 -2 and a corrected uptake coefficient (γ c ) of (1.48 ± 0.21) ×10 -6 for the former while γ obs of (3.35 ± 0.43) ×10 -3 and γ c of (7.46 ± 2.97) ×10 -7 for the latter. Under wet conditions, the presence of water altered the chemical form of sulfate and was in favor for the heterogeneous oxidation of SO 2 . The maximum sulfate formation rate was reached at 25% RH and 45% for δ-MnO 2 and γ-MnO 2 , respectively, possibly due to their different crystal structures. The results suggest that morphologies and RH are important factors influencing the heterogeneous reaction of SO 2 on mineral aerosols, and that aqueous oxidation process involving transition metals of Mn might be a potential important pathway for SO 2 oxidation in the atmosphere.

  5. Involving IDPs in the Darfur peace process

    Directory of Open Access Journals (Sweden)

    David Lanz

    2008-04-01

    Full Text Available The UN estimates that there are 2.4 millionIDPs in Darfur –over one third of the totalpopulation. There can be no meaningfulpeace process without their involvement.Giving IDPs a formal seat in official peacenegotiations is problematic but there areother ways to ensure their participation.

  6. High-efficiency SO2 removal in utility FGD systems

    International Nuclear Information System (INIS)

    Phillips, J.L.; Gray, S.; Dekraker, D.

    1995-01-01

    The U.S. Department of Energy (DOE) and the Electric Power Research Institute (EPRI) have contracted with Radian Corporation to conduct full-scale testing, process modeling, and economic evaluations of six existing utility flue gas desulfurization (FGD) systems. The project objective is to evaluate low capital cost upgrades for achieving up to 98% sulfur dioxide (SO 2 ) removal efficiency in a variety of FGD system types. The systems include dual-loop, packed absorbers at Tampa Electric Company's Big Bend Station; cocurrent, packed absorbers at Hoosier Energy's Merom Station; dual-loop absorbers with perforated-plate trays at Southwestern Electric Power Company's Pirkey Station; horizontal spray absorbers at PSI Energy's Gibson Station; venturi scrubbers at Duquesne Light's Elrama Station; and open stray absorbers at New york State Electric and Gas Corporations's (NYSEG's) Kintigh Station. All operate in an inhibited-oxidation mode except the system at Big Bend (forced oxidation), and all use limestone reagent except the Elrama system (Mg-lime). The program was conducted to demonstrate that upgrades such as performance additives and/or mechanical modifications can increase system SO 2 removal at low cost. The cost effectiveness of each upgrade has been evaluated on the basis of test results and/or process model predictions for upgraded performance and utility-specific operating and maintenance costs. Results from this upgraded performance and utility-specific operating and maintenance costs. Results from this program may lead some utilities to use SO 2 removal upgrades as an approach for compliance with phase 2 of Title IV of the Clean Air Act Amendments (CAAA) of 1990. This paper summarizes the results of testing, modeling, and economic evaluations that have been completed since July, 1994

  7. Ecological behavior and effects of energy related pollutants. Progress report, June 1976--August 1977. [SO2 impact on survival and stability of plant species; fallout /sup 137/Cs transfer processes in Southeastern Coastal Plain ecosystem

    Energy Technology Data Exchange (ETDEWEB)

    Platt, R.B.; Ragsdale, H.L.; Murdy, W.H.; Shure, D.J.

    1977-10-25

    The impact of SO/sub 2/ on the survival and stability of plant populations and communities was studied. The results to date have an important bearing on the adequacy of current permissible ambient air levels for SO/sub 2/. Atmospheric SO/sub 2/ concentrations at near permissible levels had a significant adverse effect on sexual reproduction processes, which results in a reduced number of viable seeds, in all 8 populations tested. Implications for both natural and agricultural plant species and possible significant losses of fruit production are discussed. An ecological implication of the invisible effect of fruit and seed mortality is postulated since the life cycle of many insects and the trophic relations of numerous animals depend, at least in part, on fruit production by trees and shrubs. Hence, there is a potential for disruptive effects on ecosystem level processes. Results are also reported from four systems-oriented studies within the Lower Three Runs Creek Watershed, Savannah River Plant, to examine fallout /sup 137/Cs transfer processes in ecological systems characteristic of the Southeastern Coastal Plain. These studies were carried out within the stream and its floodplains, within floodplains along the stream gradient, in upland aquatic systems (Carolina Bays), and in the upland scrub-oak forest system. Results are discussed.

  8. Reversible physical absorption of SO2 by ionic liquids

    DEFF Research Database (Denmark)

    Huang, Jun; Riisager, Anders; Fehrmann, Rasmus

    2006-01-01

    Ionic liquids can reversibly absorb large amounts of molecular SO2 gas under ambient conditions with the gas captured in a restricted configuration, possibly allowing SO2 to probe the internal cavity structures in ionic liquids besides being useful for SO2 removal in pollution control....

  9. Impact of burning oil as auxiliary fuel in kraft recovery furnaces upon SO2 emissions

    International Nuclear Information System (INIS)

    Someshwar, A.V.; Caron, A.L.; Pinkerton, J.E.

    1990-01-01

    The relationship between burning medium sulfur oil as auxiliary fuel in kraft recovery furnaces and SO 2 emissions was examined. Analysis of long-term CEMS SO 2 data from four furnaces shows no increase in SO 2 emissions as a result of oil burning. The results of field tests conducted at four furnaces while co-firing oil with liquor (up to 34% of total heat input) show that (1) average SO 2 emissions during the oil firing period either decreased or remained unchanged; (2) the overall sulfur retention within the furnace remained consistently high (more than 90%) with increasing levels of oil burning; (3) apportioning stack SO 2 emissions between those derived from oil and black liquor was infeasible. The results indicate that the same alkali fume generation processes that lead to the efficient capture of SO 2 resulting from black liquor combustion may be responsible for the capture of SO 2 resulting from sulfur-containing oil combustion

  10. Charge exchange processes involving iron ions

    International Nuclear Information System (INIS)

    Phaneuf, R.A.

    1985-01-01

    A review and evaluation is given of the experimental data which are available for charge exchange processes involving iron ions and neutral H, H 2 and He. Appropriate scaling laws are presented, and their accuracy estimated for these systems. A bibliography is given of available data sources, as well as of useful data compilations and review articles. A procedure is recommended for providing single approximate formulae to the fusion community to describe total cross sections for electron capture by partially-stripped Fe/sup q+/ ions in collisions with H, H 2 and He, based on the scaling relationships suggested by Janev and Hvelplund

  11. On the SO2 problem in power engineering

    International Nuclear Information System (INIS)

    Boyadjiev, C.

    2011-01-01

    The presented theoretical analysis shows, that the low SO2 concentration in the waste gases of the thermal power plants needs an irreversible chemical reactions of SO2 with alkaline reagents in the liquid phase in case of gas-liquid dispersion system. For the purification of huge amounts of waste gases must be used inexpensive reagents (CaCO 3 suspension). The presence of the active component in the absorbent as both a solution and solid phase leads to an increase of the absorption capacity of the absorbent, but the introduction of a new process (the dissolution of the solid phase) creates conditions for a variation of the absorption mechanism (interphase mass transfer through two interphase surfaces - gas/liquid and liquid/solid). At these conditions the mass transfer resistance is distributed in the both phases, i.e. the convection-diffusion equations of SO2 (in gas and liquid phases) and CaCO 3 (in liquid phase) must be solved together. The impossibility for the solution of the convection-diffusion equations in gas-liquid dispersion system leads to the necessity of using a diffusion type of models, where the velocity and concentration distributions in column apparatuses are replaced by the average values of the velocity and concentration over the cross-sectional area of the column. The parameters in these type of models replace the effects, the radial non-uniformities of the velocity and the concentration distributions at the cross-sectional area of the column. They can be obtained, using experimental data

  12. SO(2N) and SU(N) gauge theories

    OpenAIRE

    Lau, Richard; Teper, Michael

    2013-01-01

    We present our preliminary results of SO(2N) gauge theories, approaching the large-N limit. SO(2N) theories may help us to understand QCD at finite chemical potential since there is an orbifold equivalence between SO(2N) and SU(N) gauge theories at large-N and SO(2N) theories do not have the sign problem present in QCD. We consider the string tensions, mass spectra, and deconfinement temperatures in the SO(2N) pure gauge theories in 2+1 dimensions, comparing them to their corresponding SU(N) ...

  13. Continuous desulfurization and bacterial community structure of an integrated bioreactor developed to treat SO2 from a gas stream.

    Science.gov (United States)

    Lin, Jian; Li, Lin; Ding, Wenjie; Zhang, Jingying; Liu, Junxin

    2015-11-01

    Sulfide dioxide (SO2) is often released during the combustion processes of fossil fuels. An integrated bioreactor with two sections, namely, a suspended zone (SZ) and immobilized zone (IZ), was applied to treat SO2 for 6months. Sampling ports were set in both sections to investigate the performance and microbial characteristics of the integrated bioreactor. SO2 was effectively removed by the synergistic effect of the SZ and IZ, and more than 85% removal efficiency was achieved at steady state. The average elimination capacity of SO2 in the bioreactor was 2.80g/(m(3)·hr) for the SZ and 1.50g/(m(3)·hr) for the IZ. Most SO2 was eliminated in the SZ. The liquid level of the SZ and the water content ratio of the packing material in the IZ affected SO2 removal efficiency. The SZ served a key function not only in SO2 elimination, but also in moisture maintenance for the IZ. The desired water content in IZ could be feasibly maintained without any additional pre-humidification facilities. Clone libraries of 16S rDNA directly amplified from the DNA of each sample were constructed and sequenced to analyze the community composition and diversity in the individual zones. The desulfurization bacteria dominated both zones. Paenibacillus sp. was present in both zones, whereas Ralstonia sp. existed only in the SZ. The transfer of SO2 to the SZ involved dissolution in the nutrient solution and biodegradation by the sulfur-oxidizing bacteria. This work presents a potential biological treatment method for waste gases containing hydrophilic compounds. Copyright © 2015. Published by Elsevier B.V.

  14. Chemisorption of SO2 at the surface of In2O3 modified by zink

    International Nuclear Information System (INIS)

    Vinokurova, M.V.; Derlyukova, L.E.; Vinokurov, A.A.

    2005-01-01

    Chemisorption of SO 2 and O 2 at the surface of In 2 O 3 involving zink addition (0.4-2.7 at.%) are investigated in the temperature range 22-200 Deg C. No less than three forms of sorbed SO 2 are available at the surface of modified In 2 O 3 . Temperature effects on the ratio of forms of SO 2 sorption and, consequently, on varying the electric conductivity. Previous sorption of O 2 is favorable to the formation of donor form of chemisorbed SO 2 [ru

  15. 40 CFR 97.288 - CAIR SO2 allowance allocations to CAIR SO2 opt-in units.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 20 2010-07-01 2010-07-01 false CAIR SO2 allowance allocations to CAIR SO2 opt-in units. 97.288 Section 97.288 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) FEDERAL NOX BUDGET TRADING PROGRAM AND CAIR NOX AND SO2 TRADING PROGRAMS...

  16. 40 CFR 96.288 - CAIR SO2 allowance allocations to CAIR SO2 opt-in units.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 20 2010-07-01 2010-07-01 false CAIR SO2 allowance allocations to CAIR SO2 opt-in units. 96.288 Section 96.288 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) NOX BUDGET TRADING PROGRAM AND CAIR NOX AND SO2 TRADING PROGRAMS FOR...

  17. Oxidation behavior of molten magnesium in atmospheres containing SO2

    International Nuclear Information System (INIS)

    Wang Xianfei; Xiong Shoumei

    2011-01-01

    Graphical abstract: Highlights: → We found the film formed on molten magnesium had a two or three layers structure. → The formation mechanism of film was investigated and a growth model was proposed. → We found the formation of MgSO 4 was critical and promoted the growth of the film. - Abstract: The microchemistry and morphology of the oxide layer formed on molten magnesium in atmospheres containing SO 2 were examined. Based on the results and the thermodynamic and kinetic calculations of oxide-growth process, a schematic oxidation mechanism is presented. The results showed that the oxide scales with network structure were generally composed of MgO, MgS, and MgSO 4 with different layers, depending on the SO 2 content, the time and the temperature. The formation of MgSO 4 was important for the formation of the protective oxide scales. The growth of the oxide scales followed the parabolic law at 973 K and was controlled by diffusion.

  18. Processes involved in solving mathematical problems

    Science.gov (United States)

    Shahrill, Masitah; Putri, Ratu Ilma Indra; Zulkardi, Prahmana, Rully Charitas Indra

    2018-04-01

    This study examines one of the instructional practices features utilized within the Year 8 mathematics lessons in Brunei Darussalam. The codes from the TIMSS 1999 Video Study were applied and strictly followed, and from the 183 mathematics problems recorded, there were 95 problems with a solution presented during the public segments of the video-recorded lesson sequences of the four sampled teachers. The analyses involved firstly, identifying the processes related to mathematical problem statements, and secondly, examining the different processes used in solving the mathematical problems for each problem publicly completed during the lessons. The findings revealed that for three of the teachers, their problem statements coded as `using procedures' ranged from 64% to 83%, while the remaining teacher had 40% of his problem statements coded as `making connections.' The processes used when solving the problems were mainly `using procedures', and none of the problems were coded as `giving results only'. Furthermore, all four teachers made use of making the relevant connections in solving the problems given to their respective students.

  19. Involving construction in the preliminary engineering process

    International Nuclear Information System (INIS)

    Mahoney, D.T. Jr.; Boccieri, S.V. Jr.

    1994-01-01

    With today's high cost associated with modifications in nuclear power plants, it is imperative that the authors continue to investigate ways to cut costs but at the same time improve efficiency and reduce radiation exposure to those directly associated with the implementation of modifications. The success associated with involving construction in the preliminary engineering process will not only cut costs and improve efficiency but will establish a Team Building concept to provide accountability to all those associated with the implementation of the task. This form of partnering focuses on the solutions rather than highlighting the difficulties. This paper will demonstrate techniques to implement such ideas and provide examples to corroborate actual successes already achieved

  20. CHEMISTRY OF SO2 AND DESOX PROCESSES ON OXIDE NANOPARTICLES.

    Energy Technology Data Exchange (ETDEWEB)

    RODRIGUEZ, J.A.

    2006-06-30

    On bulk stoichiometric oxides, SO{sub 2} mainly reacts with the O centers to form SO{sub 3} or SO{sub 4} species that decompose at elevated temperatures. Adsorption on the metal cations occurs below 300 K and does not lead to cleavage of the S-O bonds. In bulk oxides, the occupied cation bands are too stable for effective bonding interactions with the LUMO of SO{sub 2}. The effects of quantum confinement on the electronic properties of oxide nanoparticles and the structural defects that usually accompany these systems in general favor the bonding and dissociation of SO{sub 2}. Thus, nanoparticles of MgO, CaO, SrO, Al{sub 2}O{sub 3}, Fe{sub 2}O{sub 3} and CeO{sub 2} are all more efficient for sequestering SO{sub 2} than the corresponding bulk oxides. Structural imperfections in pure or metal-doped ceria nanoparticles accelerate the reduction of SO{sub 2} by CO by facilitating the formation and migration of O vacancies in the oxide surface.

  1. Online analysis of H2S and SO2 via advanced mid-infrared gas sensors.

    Science.gov (United States)

    Petruci, João Flavio da Silveira; Wilk, Andreas; Cardoso, Arnaldo Alves; Mizaikoff, Boris

    2015-10-06

    Volatile sulfur compounds (VSCs) are among the most prevalent emitted pollutants in urban and rural atmospheres. Mainly because of the versatility of sulfur regarding its oxidation state (2- to 6+), VSCs are present in a wide variety of redox-environments, concentration levels, and molar ratios. Among the VSCs, hydrogen sulfide and sulfur dioxide are considered most relevant and have simultaneously been detected within naturally and anthropogenically caused emission events (e.g., volcano emissions, food production and industries, coal pyrolysis, and various biological activities). Next to their presence as pollutants, changes within their molar ratio may also indicate natural anomalies. Prior to analysis, H2S- and SO2-containing samples are usually preconcentrated via solid sorbents and are then detected by gas chromatographic techniques. However, such analytical strategies may be of limited selectivity, and the dimensions and operation modalities of the involved instruments prevent routine field usage. In this contribution, we therefore describe an innovative portable mid-infrared chemical sensor for simultaneously determining and quantifying gaseous H2S and SO2 via coupling a substrate-integrated hollow waveguides (iHWG) serving as a highly miniaturized mid-infrared photon conduit and gas cell with a custom-made preconcentration tube and an in-line UV-converter device. Both species were collected onto a solid sorbent within the preconcentrator and then released by thermal desorption into the UV-device. Hydrogen sulfide is detected by UV-assisted quantitative conversion of the rather weak IR-absorber H2S into SO2, which provides a significantly more pronounced and distinctively detectable rovibrational signature. Modulation of the UV-device system (i.e., UV-lamp on/off) enables discriminating between SO2 generated from H2S conversion and abundant SO2 signals. After optimization of the operational parameters, calibrations in the range of 0.75-10 ppmv with a limit

  2. A Balloon Sounding Technique for Measuring SO2 Plumes

    Science.gov (United States)

    Morris, Gary A.; Komhyr, Walter D.; Hirokawa, Jun; Lefer, Barry; Krotkov, Nicholay; Ngan, Fong

    2010-01-01

    This paper reports on the development of a new technique for inexpensive measurements of SO2 profiles using a modified dual-ozonesonde instrument payload. The presence of SO2 interferes with the standard electrochemical cell (ECC) ozonesonde measurement, resulting in -1 molecule of O3 reported for each molecule of SO2 present (provided [O3] > [SO2]). In laboratory tests, an SO2 filter made with Cr03 placed on the inlet side of the sonde removes nearly 100% of the SO2 present for concentrations up to 60 ppbv and remained effective after exposure to 2.8 X 10(exp 16) molecules of SO2 [equivalent to a column approximately 150 DU (1 DU = 2.69 X 10(exp 20) molecules m(exp -2))]. Flying two ECC instruments on the same payload with one filtered and the other unfiltered yields SO2 profiles, inferred by subtraction. Laboratory tests and field experience suggest an SO2 detection limit of approximately 3 pbb with profiles valid from the surface to the ozonopause [i.e., approximately (8-10 km)]. Two example profiles demonstrate the success of this technique for both volcanic and industrial plumes.

  3. Distribution of SO_{2} and so in the Envelope of Vy-Canis Majoris: Insight Into Circumstellar Sulfur Chemistry

    Science.gov (United States)

    Adande, Gilles; Ziurys, L. M.

    2013-06-01

    Millimeter wave observations of SO_{2} and SO in the envelope of the O-rich supergiant VY-Canis Majoris have been conducted with the Submillimeter Telescope (SMT) of the Arizona Radio Observatory, between 210 and 290 GHz. A non LTE radiative transfer code has been written to fit the line profile of 22 lines of SO_{2} and 5 transitions of SO, and model their abundance and distribution within the circumstellar envelope. The rotational levels involved span a wide energy range, from 13 cm^{-1} to 104 cm^{-1} for SO_{2}, and 17 to 40 cm^{-1} for SO. The high number of transitions fitted provides strong constraints on the excitation conditions, hydrogen density and kinetic temperatures. The results will be discussed in relation to the formation processes and chemistry of these two species in O-rich molecular envelopes.

  4. The vertical distribution of volcanic SO2 plumes measured by IASI

    Directory of Open Access Journals (Sweden)

    E. Carboni

    2016-04-01

    Full Text Available Sulfur dioxide (SO2 is an important atmospheric constituent that plays a crucial role in many atmospheric processes. Volcanic eruptions are a significant source of atmospheric SO2 and its effects and lifetime depend on the SO2 injection altitude. The Infrared Atmospheric Sounding Interferometer (IASI on the METOP satellite can be used to study volcanic emission of SO2 using high-spectral resolution measurements from 1000 to 1200 and from 1300 to 1410 cm−1 (the 7.3 and 8.7 µm SO2 bands returning both SO2 amount and altitude data. The scheme described in Carboni et al. (2012 has been applied to measure volcanic SO2 amount and altitude for 14 explosive eruptions from 2008 to 2012. The work includes a comparison with the following independent measurements: (i the SO2 column amounts from the 2010 Eyjafjallajökull plumes have been compared with Brewer ground measurements over Europe; (ii the SO2 plumes heights, for the 2010 Eyjafjallajökull and 2011 Grimsvötn eruptions, have been compared with CALIPSO backscatter profiles. The results of the comparisons show that IASI SO2 measurements are not affected by underlying cloud and are consistent (within the retrieved errors with the other measurements. The series of analysed eruptions (2008 to 2012 show that the biggest emitter of volcanic SO2 was Nabro, followed by Kasatochi and Grímsvötn. Our observations also show a tendency for volcanic SO2 to reach the level of the tropopause during many of the moderately explosive eruptions observed. For the eruptions observed, this tendency was independent of the maximum amount of SO2 (e.g. 0.2 Tg for Dalafilla compared with 1.6 Tg for Nabro and of the volcanic explosive index (between 3 and 5.

  5. Ultrahigh and Selective SO2 Uptake in Inorganic Anion-Pillared Hybrid Porous Materials.

    Science.gov (United States)

    Cui, Xili; Yang, Qiwei; Yang, Lifeng; Krishna, Rajamani; Zhang, Zhiguo; Bao, Zongbi; Wu, Hui; Ren, Qilong; Zhou, Wei; Chen, Banglin; Xing, Huabin

    2017-07-01

    The efficient capture of SO 2 is of great significance in gas-purification processes including flue-gas desulfurization and natural-gas purification, but the design of porous materials with high adsorption capacity and selectivity of SO 2 remains very challenging. Herein, the selective recognition and dense packing of SO 2 clusters through multiple synergistic host-guest and guest-guest interactions by controlling the pore chemistry and size in inorganic anion (SiF 6 2- , SIFSIX) pillared metal-organic frameworks is reported. The binding sites of anions and aromatic rings in SIFSIX materials grasp every atom of SO 2 firmly via S δ+ ···F δ- electrostatic interactions and O δ- ···H δ+ dipole-dipole interactions, while the guest-guest interactions between SO 2 molecules further promote gas trapping within the pore space, which is elucidated by first-principles density functional theory calculations and powder X-ray diffraction experiments. These interactions afford new benchmarks for the highly efficient removal of SO 2 from other gases, even if at a very low SO 2 concentration. Exceptionally high SO 2 capacity of 11.01 mmol g -1 is achieved at atmosphere pressure by SIFSIX-1-Cu, and unprecedented low-pressure SO 2 capacity is obtained in SIFSIX-2-Cu-i (4.16 mmol g -1 SO 2 at 0.01 bar and 2.31 mmol g -1 at 0.002 bar). More importantly, record SO 2 /CO 2 selectivity (86-89) and excellent SO 2 /N 2 selectivity (1285-3145) are also achieved. Experimental breakthrough curves further demonstrate the excellent performance of these hybrid porous materials in removing low-concentration SO 2 . © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  6. Efficient SO2 capture by amine functionalized PEG.

    Science.gov (United States)

    Yang, Dezhong; Hou, Minqiang; Ning, Hui; Zhang, Jianling; Ma, Jun; Han, Buxing

    2013-11-07

    Polyethylene glycols (PEGs) are a class of non-toxic, non-volatile, biocompatible, and widely available polymers. In this work, we synthesized N-ethyl-N-(2-(2-(2-methoxyethoxy)ethoxy)ethyl)-2-aminoethanol (EE3AE) that combines the properties of PEG and amines, and N-decyl-N-ethyl-2-aminoethanol (DEAE). Their performances to capture SO2 were studied at different temperatures, pressures, and absorption times. The interaction between the absorbents and SO2 were characterized by NMR and FTIR techniques. It was demonstrated that both EE3AE and DEAE could absorb SO2 efficiently, and there existed chemical and physical interactions between the absorbents and SO2. In particular, the absorption capacity of EE3AE could be as high as 1.09 g SO2 per g EE3AE at 1 atm. The absorption capacity of EE3AE was much larger than that of DEAE because the ether group in the EE3AE interacted with SO2 more strongly than the alkyl group in the DEAE. The SO2 absorbed by EE3AE could be stripped out by bubbling N2 or by applying a vacuum and the EE3AE could be reused. Moreover, both absorbents exhibited a high SO2-CO2 selectivity.

  7. Observations of volcanic SO2 from MLS on Aura

    Directory of Open Access Journals (Sweden)

    H. C. Pumphrey

    2015-01-01

    Full Text Available Sulfur dioxide (SO2 is an important atmospheric constituent, particularly in the aftermath of volcanic eruptions. These events can inject large amounts of SO2 into the lower stratosphere, where it is oxidised to form sulfate aerosols; these in turn have a significant effect on the climate. The MLS instrument on the Aura satellite has observed the SO2 mixing ratio in the upper troposphere and lower stratosphere from August 2004 to the present, during which time a number of volcanic eruptions have significantly affected those regions of the atmosphere. We describe the MLS SO2 data and how various volcanic events appear in the data. As the MLS SO2 data are currently not validated we take some initial steps towards their validation. First we establish the level of internal consistency between the three spectral regions in which MLS is sensitive to SO2. We compare SO2 column values calculated from MLS data to total column values reported by the OMI instrument. The agreement is good (within about 1 DU in cases where the SO2 is clearly at altitudes above 147 hPa.

  8. Ultrastructural study of the effect of air pollution by SO2 on the ...

    African Journals Online (AJOL)

    kemrilib

    Sulfur dioxide (SO2) has been associated with excessive mortality during air pollution disasters such as ... epithelium. It is suggested that this synergistic effect is due to the carbon particles adsorbing. SO2 ... in refrigeration plants, fruit processing, manufacturing .... concentration range was absorbed on the nasal mucosa [29 ...

  9. Defining stakeholder involvement in participatory design processes

    NARCIS (Netherlands)

    Vink, P.; Imada, A.S.; Zink, K.J.

    2008-01-01

    A participatory approach could be used to implement work place or organizational improvements. However, the question is which participants should be involved and how. In this paper the theoretical involvement in different steps of a linear stepwise approach is described and compared with the latest

  10. Measurements of SO2 in the Mount St. Helens debris

    International Nuclear Information System (INIS)

    Kerr, J.B.; Evans, F.J.; Mateer, C.L.

    1982-01-01

    Routine measurements of ozone and SO 2 are made with the Dobson and Brewer spectrophotometers at the Atmospheric Environment Service in Downsview Ontario. On May 20 and 21, 1980, large values of column SO 2 were observed with both spectrophotometers at the time of passage of the Mount St. Helens debris. Enhanced SO 2 values were first observed at 1800Z on May 20. The maximum column amount of SO 2 measured was 0.06 cm at 2200 Z. On May 21, SO 2 values slowly decreased from 0.03 cm at 1100 Z cm to 0.01 cm at 2000Z. Typical SO 2 amounts due to pollution at the Downsview site are approximately 0.003 to 0.005 cm. At the same time of maximum SO 2 enhancement, both Dobson and Brewer spectrophotometers measured a 0.040 cm decrease of total ozone. It is not clear whether the decrease of total ozone was caused by the volcanic cloud or natural ozone variability. Air mass trajectories indicate that the altitude of the debris cloud, which passed over Downsview at the time, was between 10 km and 12 km

  11. Surface Hydrophobicity Causes SO2 Tolerance in Lichens

    Science.gov (United States)

    Hauck, Markus; Jürgens, Sascha-René; Brinkmann, Martin; Herminghaus, Stephan

    2008-01-01

    Background and Aims The superhydrophobicity of the thallus surface in one of the most SO2-tolerant lichen species, Lecanora conizaeoides, suggests that surface hydrophobicity could be a general feature of lichen symbioses controlling their tolerance to SO2. The study described here tests this hypothesis. Methods Water droplets of the size of a raindrop were placed on the surface of air-dry thalli in 50 lichen species of known SO2 tolerance and contact angles were measured to quantify hydrophobicity. Key Results The wettability of lichen thalli ranges from strongly hydrophobic to strongly hydrophilic. SO2 tolerance of the studied lichen species increased with increasing hydrophobicity of the thallus surface. Extraction of extracellular lichen secondary metabolites with acetone reduced, but did not abolish the hydrophobicity of lichen thalli. Conclusions Surface hydrophobicity is the main factor controlling SO2 tolerance in lichens. It presumably originally evolved as an adaptation to wet habitats preventing the depression of net photosynthesis due to supersaturation of the thallus with water. Hydrophilicity of lichen thalli is an adaptation to dry or humid, but not directly rain-exposed habitats. The crucial role of surface hydrophobicity in SO2 also explains why many markedly SO2-tolerant species are additionally tolerant to other (chemically unrelated) toxic substances including heavy metals. PMID:18077467

  12. The US SO2 Auction and Environmental Regulation

    DEFF Research Database (Denmark)

    Svendsen, Gert Tinggaard; Christensen, J.L.

    1999-01-01

    The US Acid Rain Program (ARP) is now well-established. The ARP relies on tradable permits and includes an annual revenue-neutral SO2 auction. Has this auction been an important factor in establishing low transaction costs and a successful market? In answering this question, we first compare...... the price signals from the SO2 auction to those found in the market. Second, we try to explain empirical outcomes by analyzing strategic incentives and the number of buyers and sellers in the auction. The policy recommendation is that the non-discriminative SO2 auction is a very useful tool for kick...

  13. Customer Involvement in the Game Development Process

    Directory of Open Access Journals (Sweden)

    Kaja Prystupa-Rządca

    2015-01-01

    Full Text Available The creative industry is a fast developing sector of economy in many countries. Growing competition in this area has led many companies to implement strategy of users' involvement in product development in order to deliver products that are more aligned with customers’ needs. On the other hand, the attempt to align the customers’ expectations with artistic creativity may create tensions. Therefore, the aim of the research is to examine the methods of users’ involvement in product development and real impact of the users on project design. The obtained findings are based on two-year qualitative research project conducted in game development companies.

  14. Impact of coal combustion from thermal power plant: estimates on ambient SO2 levels

    International Nuclear Information System (INIS)

    Joshi, P.V.

    1991-01-01

    Using a Gaussian dispersion model, ambient Ground Levels Concentrations (GLC) of SO 2 due to Nashik Thermal Power Plant have been computed. Annual GLC in 16 cardinal sectors and concentration levels in 6 atmospheric stability classes have been estimated as a function of down wind distance. The values are compared with national ambient air quality standard and risk involved due to the release of SO 2 from power plant has been assessed. (author). 8 refs., 2 appendixes

  15. Integrated assessment of CO2 and SO2 policies in North East Asia

    International Nuclear Information System (INIS)

    Chae, Yeora; Hope, Chris

    2003-01-01

    This study quantifies the costs and impacts of six scenarios for carbon dioxide (CO 2 ) and sulphur dioxide (SO 2 ) emissions in North East Asia (NEA) within an integrated probabilistic analysis. The inclusion of the cooling effect of sulphates means that CO 2 control in China would be likely to increase the regional temperature in NEA in the short-term. This is because CO 2 control measures would also automatically control SO 2 emissions, and so reduce their cooling effect. The scenario that involves no control for CO 2 and SO 2 emissions has the lowest mean total cumulative net present cost (NPC) as compared to scenarios with various SO 2 controls or with CO 2 reduced to 5% below year 1990 levels (in China and Japan), or any combination of SO 2 + CO 2 controls at these levels. The mean value of the total cumulative NPC of climate change damage, acid rain damage, CO 2 and SO 2 control cost in China for no CO 2 or SO 2 control is about US$ 0.1 trillion, compared, for instance, to about US$ 1.1 trillion for CO 2 emission stabilisation at 1990 levels and no SO 2 control. SO 2 control also brings more disadvantages than advantages in China and Japan. The higher mean climate change impacts and control costs outweigh the benefit of lower acid rain damage. However, strict SO 2 control brings more benefits than costs in South Korea where there is a large urban population and the sensitivity to acid rain is high. However, the impacts of emissions and valuation of these effects are very uncertain. Uncertainty analysis shows that the key determinants of the total NPC of costs and damages are exported climate change damages, followed by domestic climate change damages, and acid rain damages. The use of other valuation methods would make health damage bigger than this study's estimation and acid rain damage could be a major concern in the future

  16. Next Generation Aura-OMI SO2 Retrieval Algorithm: Introduction and Implementation Status

    Science.gov (United States)

    Li, Can; Joiner, Joanna; Krotkov, Nickolay A.; Bhartia, Pawan K.

    2014-01-01

    We introduce our next generation algorithm to retrieve SO2 using radiance measurements from the Aura Ozone Monitoring Instrument (OMI). We employ a principal component analysis technique to analyze OMI radiance spectral in 310.5-340 nm acquired over regions with no significant SO2. The resulting principal components (PCs) capture radiance variability caused by both physical processes (e.g., Rayleigh and Raman scattering, and ozone absorption) and measurement artifacts, enabling us to account for these various interferences in SO2 retrievals. By fitting these PCs along with SO2 Jacobians calculated with a radiative transfer model to OMI-measured radiance spectra, we directly estimate SO2 vertical column density in one step. As compared with the previous generation operational OMSO2 PBL (Planetary Boundary Layer) SO2 product, our new algorithm greatly reduces unphysical biases and decreases the noise by a factor of two, providing greater sensitivity to anthropogenic emissions. The new algorithm is fast, eliminates the need for instrument-specific radiance correction schemes, and can be easily adapted to other sensors. These attributes make it a promising technique for producing long-term, consistent SO2 records for air quality and climate research. We have operationally implemented this new algorithm on OMI SIPS for producing the new generation standard OMI SO2 products.

  17. Intercomparison of SO2 camera systems for imaging volcanic gas plumes

    Science.gov (United States)

    Kern, Christoph; Lübcke, Peter; Bobrowski, Nicole; Campion, Robin; Mori, Toshiya; Smekens, Jean-François; Stebel, Kerstin; Tamburello, Giancarlo; Burton, Mike; Platt, Ulrich; Prata, Fred

    2015-07-01

    SO2 camera systems are increasingly being used to image volcanic gas plumes. The ability to derive SO2 emission rates directly from the acquired imagery at high time resolution allows volcanic process studies that incorporate other high time-resolution datasets. Though the general principles behind the SO2 camera have remained the same for a number of years, recent advances in CCD technology and an improved understanding of the physics behind the measurements have driven a continuous evolution of the camera systems. Here we present an intercomparison of seven different SO2 cameras. In the first part of the experiment, the various technical designs are compared and the advantages and drawbacks of individual design options are considered. Though the ideal design was found to be dependent on the specific application, a number of general recommendations are made. Next, a time series of images recorded by all instruments at Stromboli Volcano (Italy) is compared. All instruments were easily able to capture SO2 clouds emitted from the summit vents. Quantitative comparison of the SO2 load in an individual cloud yielded an intra-instrument precision of about 12%. From the imagery, emission rates were then derived according to each group's standard retrieval process. A daily average SO2 emission rate of 61 ± 10 t/d was calculated. Due to differences in spatial integration methods and plume velocity determination, the time-dependent progression of SO2 emissions varied significantly among the individual systems. However, integration over distinct degassing events yielded comparable SO2 masses. Based on the intercomparison data, we find an approximate 1-sigma precision of 20% for the emission rates derived from the various SO2 cameras. Though it may still be improved in the future, this is currently within the typical accuracy of the measurement and is considered sufficient for most applications.

  18. Intercomparison of SO2 camera systems for imaging volcanic gas plumes

    Science.gov (United States)

    Kern, Christoph; Lübcke, Peter; Bobrowski, Nicole; Campion, Robin; Mori, Toshiya; Smekens, Jean-Francois; Stebel, Kerstin; Tamburello, Giancarlo; Burton, Mike; Platt, Ulrich; Prata, Fred

    2015-01-01

    SO2 camera systems are increasingly being used to image volcanic gas plumes. The ability to derive SO2 emission rates directly from the acquired imagery at high time resolution allows volcanic process studies that incorporate other high time-resolution datasets. Though the general principles behind the SO2 camera have remained the same for a number of years, recent advances in CCD technology and an improved understanding of the physics behind the measurements have driven a continuous evolution of the camera systems. Here we present an intercomparison of seven different SO2 cameras. In the first part of the experiment, the various technical designs are compared and the advantages and drawbacks of individual design options are considered. Though the ideal design was found to be dependent on the specific application, a number of general recommendations are made. Next, a time series of images recorded by all instruments at Stromboli Volcano (Italy) is compared. All instruments were easily able to capture SO2 clouds emitted from the summit vents. Quantitative comparison of the SO2 load in an individual cloud yielded an intra-instrument precision of about 12%. From the imagery, emission rates were then derived according to each group's standard retrieval process. A daily average SO2 emission rate of 61 ± 10 t/d was calculated. Due to differences in spatial integration methods and plume velocity determination, the time-dependent progression of SO2 emissions varied significantly among the individual systems. However, integration over distinct degassing events yielded comparable SO2 masses. Based on the intercomparison data, we find an approximate 1-sigma precision of 20% for the emission rates derived from the various SO2 cameras. Though it may still be improved in the future, this is currently within the typical accuracy of the measurement and is considered sufficient for most applications.

  19. Double C-H activation of ethane by metal-free SO2*+ radical cations.

    Science.gov (United States)

    de Petris, Giulia; Cartoni, Antonella; Troiani, Anna; Barone, Vincenzo; Cimino, Paola; Angelini, Giancarlo; Ursini, Ornella

    2010-06-01

    The room-temperature C-H activation of ethane by metal-free SO(2)(*+) radical cations has been investigated under different pressure regimes by mass spectrometric techniques. The major reaction channel is the conversion of ethane to ethylene accompanied by the formation of H(2)SO(2)(*+), the radical cation of sulfoxylic acid. The mechanism of the double C-H activation, in the absence of the single activation product HSO(2)(+), is elucidated by kinetic studies and quantum chemical calculations. Under near single-collision conditions the reaction occurs with rate constant k=1.0 x 10(-9) (+/-30%) cm(3) s(-1) molecule(-1), efficiency=90%, kinetic isotope effect k(H)/k(D)=1.1, and partial H/D scrambling. The theoretical analysis shows that the interaction of SO(2)(*+) with ethane through an oxygen atom directly leads to the C-H activation intermediate. The interaction through sulfur leads to an encounter complex that rapidly converts to the same intermediate. The double C-H activation occurs by a reaction path that lies below the reactants and involves intermediates separated by very low energy barriers, which include a complex of the ethyl cation suitable to undergo H/D scrambling. Key issues in the observed reactivity are electron-transfer processes, in which a crucial role is played by geometrical constraints. The work shows how mechanistic details disclosed by the reactions of metal-free electrophiles may contribute to the current understanding of the C-H activation of ethane.

  20. Innovative Pedagogical Processes Involving Educational Technology

    DEFF Research Database (Denmark)

    Weitze, Charlotte Lærke

    to create motivating learning for the students. This was done by examining the three actors in the educational institution (students, teachers and the surrounding organisation) individually and relationally. The design-based research project developed knowledge in co-design processes with the three actors...

  1. Microwave heating processes involving carbon materials

    Energy Technology Data Exchange (ETDEWEB)

    Menendez, J.A.; Arenillas, A.; Fidalgo, B.; Fernandez, Y.; Zubizarreta, L.; Calvo, E.G.; Bermudez, J.M. [Instituto Nacional del Carbon, CSIC, Apartado 73, 33080 Oviedo (Spain)

    2010-01-15

    Carbon materials are, in general, very good absorbents of microwaves, i.e., they are easily heated by microwave radiation. This characteristic allows them to be transformed by microwave heating, giving rise to new carbons with tailored properties, to be used as microwave receptors, in order to heat other materials indirectly, or to act as a catalyst and microwave receptor in different heterogeneous reactions. In recent years, the number of processes that combine the use of carbons and microwave heating instead of other methods based on conventional heating has increased. In this paper some of the microwave-assisted processes in which carbon materials are produced, transformed or used in thermal treatments (generally, as microwave absorbers and catalysts) are reviewed and the main achievements of this technique are compared with those obtained by means of conventional (non microwave-assisted) methods in similar conditions. (author)

  2. Continuous SO2 flux measurements for Vulcano Island, Italy

    Directory of Open Access Journals (Sweden)

    Fabio Vita

    2012-06-01

    Full Text Available The La Fossa cone of Vulcano Island (Aeolian Archipelago, Italy is a closed conduit volcano. Today, Vulcano Island is characterized by sulfataric activity, with a large fumarolic field that is mainly located in the summit area. A scanning differential optical absorption spectroscopy instrument designed by the Optical Sensing Group of Chalmers University of Technology in Göteborg, Sweden, was installed in the framework of the European project "Network for Observation of Volcanic and Atmospheric Change", in March 2008. This study presents the first dataset of SO2 plume fluxes recorded for a closed volcanic system. Between 2008 and 2010, the SO2 fluxes recorded showed average values of 12 t.d–1 during the normal sulfataric activity of Vulcano Island, with one exceptional event of strong degassing that occurred between September and December, 2009, when the SO2 emissions reached up to 100 t.d–1.

  3. Emission control of SO2 and NOx by irradiation methods

    International Nuclear Information System (INIS)

    Radoiu, Marilena T.; Martin, Diana I.; Calinescu, Ioan

    2003-01-01

    Microwave discharges at 2.45 GHz frequency and accelerated electron beams operated at atmospheric pressure in synthetic gas mixtures containing N 2 , O 2 , CO 2 , SO 2 , and NO x are investigated experimentally for various gas mixture constituents and operating conditions, with respect to their ability to purify exhaust gases. An original experimental unit easily adaptable for both separate and simultaneous irradiation with microwaves and electron beams was set up. The simultaneous treatment with accelerated electron beams and microwaves was found to increase the removal efficiency of NO x and SO 2 and also helped to reduce the total required dose rate with ∼30%. Concomitant removal of NO x (∼80%) and SO 2 (>95%) by precipitation with ammonia was achieved

  4. Sulfate cooling effects on climate through in-cloud oxidation of anthropogenic SO2

    International Nuclear Information System (INIS)

    Lelieveld, J.; Heintzenberg, J.

    1992-01-01

    Anthropogenic SO 2 emissions may exert a significant cooling effect on climate in the Northern Hemisphere through backscattering of solar radiation by sulfate particles. Earlier estimates of the sulfate climate forcing were based on a limited number of sulfate-scattering correlation measurements from which a high sulfate-scattering efficiency was derived. Model results suggest that cloud processing of air is the underlying mechanism. aqueous phase oxidation of SO 2 into sulfate and the subsequent release of the dry aerosol by cloud evaporation render sulfate a much more efficient scatterer than through gas-phase SO 2 oxidation

  5. Effect of SO2 concentration on polyphenol development during red wine micro-oxygenation.

    Science.gov (United States)

    Tao, Jianxiong; Dykes, Stuart I; Kilmartin, Paul A

    2007-07-25

    A Merlot wine in 15 L research tanks was subjected to micro-oxygenation at 10 mL O2 per liter of wine per month over a 16 week period with additions of 0, 50, 100, and 200 mg/L SO2. A large decrease in monomeric anthocyanins and flavan-3-ols was seen in wines with a lower concentration of SO2, coupled with an increase in nonbleachable pigments; an increase in tannin, measured using precipitation with methyl cellulose; and a greater size and red coloration of a proanthocyanidin extract obtained using Sephadex LH-20. These changes were largely suppressed in wines initially treated with 200 mg/L SO2 and occurred more slowly in wines stored in bottles in the absence of O2. The concentration of SO2 is shown to regulate the polyphenol chemistry involved in the formation of polymeric pigments and changes in tannin structure affecting wine astringency.

  6. SO2 oxidation catalyst model systems characterized by thermal methods

    DEFF Research Database (Denmark)

    Hatem, G; Eriksen, Kim Michael; Gaune-Escard, M

    2002-01-01

    The molten salts M2S2O7 and MHSO4, the binary molten salt Systems M2S2O7-MHSO4 and the molten salt-gas systems M2S2O7 V2O5 and M2S2O7-M2SO4 V2O5 (M = Na, K, Rb, Cs) in O-2, SO2 and At atmospheres have been investigated by thermal methods like calorimetry, Differential Enthalpic Analysis (DEA) and...... to the mechanism Of SO2 oxidation by V2O5 based industrial catalysts....

  7. Electrochemical redox processes involving soluble cerium species

    International Nuclear Information System (INIS)

    Arenas, L.F.; Ponce de León, C.; Walsh, F.C.

    2016-01-01

    Highlights: • The relevance of cerium in laboratory and industrial electrochemistry is considered. • The history of fundamental electrochemical studies and applications is considered. • The chemistry, redox thermodynamics and electrode kinetics of cerium are summarised. • The uses of cerium ions in synthesis, energy storage, analysis and environmental treatment are illustrated. • Research needs and development perspectives are discussed. - Abstract: Anodic oxidation of cerous ions and cathodic reduction of ceric ions, in aqueous acidic solutions, play an important role in electrochemical processes at laboratory and industrial scale. Ceric ions, which have been used for oxidation of organic wastes and off-gases in environmental treatment, are a well-established oxidant for indirect organic synthesis and specialised cleaning processes, including oxide film removal from tanks and process pipework in nuclear decontamination. They also provide a classical reagent for chemical analysis in the laboratory. The reversible oxidation of cerous ions is an important reaction in the positive compartment of various redox flow batteries during charge and discharge cycling. A knowledge of the thermodynamics and kinetics of the redox reaction is critical to an understanding of the role of cerium redox species in these applications. Suitable choices of electrode material (metal or ceramic; coated or uncoated), geometry/structure (2-or 3-dimensional) and electrolyte flow conditions (hence an acceptable mass transport rate) are critical to achieving effective electrocatalysis, a high performance and a long lifetime. This review considers the electrochemistry of soluble cerium species and their diverse uses in electrochemical technology, especially for redox flow batteries and mediated electrochemical oxidation.

  8. Kinematic study of O--ion formation from dissociative electron attachment to SO2

    Science.gov (United States)

    Jana, Irina; Nandi, Dhananjay

    2018-04-01

    We report a complete kinematic study of O--ion formation due to dissociative electron attachment to SO2 using the velocity slice imaging technique in the incident electron energy range over the resonances. Two resonances are observed at 5.2 and 7.5 eV, respectively. From the kinetic energy distribution, the two resonances are observed to have the same threshold energy, pointing to the fact that the two processes, giving rise to the two resonant peaks, have the same dissociation limit. From the angular distribution results we identified the involvement of an A1 and a combination of A1+B2 temporary negative-ion state(s) for the first and second resonances, respectively.

  9. Motivational Influences on Cognition: Task Involvement, Ego Involvement, and Depth of Information Processing.

    Science.gov (United States)

    Graham, Sandra; Golan, Shari

    1991-01-01

    Task involvement and ego involvement were studied in relation to depth of information processing for 126 fifth and sixth graders in 2 experiments. Ego involvement resulted in poorer word recall at deep rather than shallow information processing levels. Implications for the study of motivation are discussed. (SLD)

  10. Simultaneous adsorption of SO2 and NO from flue gas over mesoporous alumina.

    Science.gov (United States)

    Sun, Xin; Tang, Xiaolong; Yi, Honghong; Li, Kai; Ning, Ping; Huang, Bin; Wang, Fang; Yuan, Qin

    2015-01-01

    Mesoporous alumina (MA) with a higher ability to simultaneously remove SO2 and NO was prepared by the evaporation-induced self-assembly process. The adsorption capacities of MA are 1.79 and 0.702 mmol/g for SO2 and NO, respectively. The Brunauer-Emmett-Teller method was used to characterize the adsorbent. Simultaneous adsorption of SO2 and NO from flue gas over MA in different operating conditions had been studied in a fixed bed reactor. The effects of temperature, oxygen concentration and water vapour were investigated. The experimental results showed that the optimum temperature for MA to simultaneously remove SO2 and NO was 90°C. The simultaneous adsorption capacities of SO2 and NO could be enhanced by increasing O2 when its concentration was below 5%. The changes of simultaneous adsorption capacities were not obvious when O2 concentration was above 5%. The increase in relative humidity results in an increase after dropping of SO2 adsorption capacity, whereas the adsorption capacity of NO showed an opposite trend. The results suggest that MA is a great adsorbent for simultaneous removal of SO2 and NO from flue gas.

  11. Sulfation of Condensed Potassium Chloride by SO2

    DEFF Research Database (Denmark)

    Sengeløv, Louise With; Hansen, Troels Bruun; Bartolomé, Carmen

    2013-01-01

    The interaction between alkali chloride and sulfur oxides has important implications for deposition and corrosion in combustion of biomass. In the present study, the sulfation of particulate KCl (90–125 μm) by SO2 was studied in a fixed bed reactor in the temperature range 673–1023 K and with rea......The interaction between alkali chloride and sulfur oxides has important implications for deposition and corrosion in combustion of biomass. In the present study, the sulfation of particulate KCl (90–125 μm) by SO2 was studied in a fixed bed reactor in the temperature range 673–1023 K...... and with reactant concentrations of 500–3000 ppm SO2, 1–20% O2, and 4–15% H2O. The degree of sulfation was monitored by measuring the formation of HCl. Analysis of the solid residue confirmed that the reaction proceeds according to a shrinking core model and showed the formation of an eutectic at higher...... temperatures. On the basis of the experimental results, a rate expression for the sulfation reaction was derived. The model compared well with literature data for sulfation of KCl and NaCl, and the results indicate that it may be applied at even higher SO2 concentrations and temperatures than those...

  12. High-throughput technology for novel SO2 oxidation catalysts

    International Nuclear Information System (INIS)

    Loskyll, Jonas; Stoewe, Klaus; Maier, Wilhelm F

    2011-01-01

    We review the state of the art and explain the need for better SO 2 oxidation catalysts for the production of sulfuric acid. A high-throughput technology has been developed for the study of potential catalysts in the oxidation of SO 2 to SO 3 . High-throughput methods are reviewed and the problems encountered with their adaptation to the corrosive conditions of SO 2 oxidation are described. We show that while emissivity-corrected infrared thermography (ecIRT) can be used for primary screening, it is prone to errors because of the large variations in the emissivity of the catalyst surface. UV-visible (UV-Vis) spectrometry was selected instead as a reliable analysis method of monitoring the SO 2 conversion. Installing plain sugar absorbents at reactor outlets proved valuable for the detection and quantitative removal of SO 3 from the product gas before the UV-Vis analysis. We also overview some elements used for prescreening and those remaining after the screening of the first catalyst generations. (topical review)

  13. Cost-effective control of SO2 emissions in Asia

    NARCIS (Netherlands)

    Cofala, J.; Amann, M.; Gyarfas, F.; Schoepp, F.; Boudri, J.C.; Hordijk, L.; Kroeze, C.; Li Junfeng,; Dai Lin, D.; Panwar, T.S.; Gupta, S.

    2004-01-01

    Despite recent efforts to limit the growth of SO2 emissions in Asia, the negative environmental effects of sulphur emissions are likely to further increase in the future. This paper presents an extension of the RAINS-Asia integrated assessment model for acidification in Asia with an optimisation

  14. Historical analysis of SO2 pollution control policies in China.

    Science.gov (United States)

    Gao, Cailing; Yin, Huaqiang; Ai, Nanshan; Huang, Zhengwen

    2009-03-01

    Coal is not only an important energy source in China but also a major source of air pollution. Because of this, China's national sulfur dioxide (SO(2)) emissions have been the highest in the world for many years, and since the 1990s, the territory of China's south and southwest has become the third largest acid-rain-prone region in the world. In order to control SO(2) emissions, the Chinese government has formulated and promulgated a series of policies and regulations, but it faces great difficulties in putting them into practice. In this retrospective look at the history of SO(2) control in China, we found that Chinese SO(2) control policies have become increasingly strict and rigid. We also found that the environmental policies and regulations are more effective when central officials consistently give environmental protection top priority. Achieving China's environmental goals, however, has been made difficult by China's economic growth. Part of this is due to the practice of environmental protection appearing in the form of an ideological "campaign" or "storm" that lacks effective economic measures. More recently, better enforcement of environmental laws and regulations has been achieved by adding environmental quality to the performance assessment metrics for leaders at all levels. To continue making advances, China needs to reinforce the economic and environmental assessments for pollution control projects and work harder to integrate economic measures into environmental protection. Nonetheless, China has a long way to go before economic growth and environmental protection are balanced.

  15. 76 FR 61098 - Guidance for 1-Hour SO2

    Science.gov (United States)

    2011-10-03

    ...Notice is hereby given that the EPA has posted its draft non- binding guidance titled, ``Guidance for 1-Hour SO2 NAAQS SIP Submissions'' on its Web site. The EPA invites public comments on this guidance document during the comment period specified below, and plans to issue an updated version of the guidance after reviewing timely submitted comments.

  16. Monitoring the dry deposition of SO2 in the Netherlands

    NARCIS (Netherlands)

    Erisman JW; Versluis AH; Verplanke TAJW; Haan D de; Anink D; Elzakker BG van; Aalst RM van

    1989-01-01

    A micrometeorological gradient method has been applied to monitor SO2 dry deposition fluxes on a routine basis. Results of a feasibility study during 1987 to 1989 at a rural site in the Netherlands demonstrated that this method can be used to measure dry deposition flux and deposition velocity

  17. SO2 : Nutrient or toxin for Chinese cabbage

    NARCIS (Netherlands)

    Yang, Liping

    2005-01-01

    Chinese cabbage (Brassica pekinensis) is one of the most important high-yield vegetable crops in China, and is often cultivated around big cities. Atmospheric SO2 pollution may affect Chinese cabbage, which is usually produced under intensive farming practice with low-sulfur or even sulfur-free

  18. Spatially resolved SO2 flux emissions from Mt Etna

    Science.gov (United States)

    Bitetto, M.; Delle Donne, D.; Tamburello, G.; Battaglia, A.; Coltelli, M.; Patanè, D.; Prestifilippo, M.; Sciotto, M.; Aiuppa, A.

    2016-01-01

    Abstract We report on a systematic record of SO2 flux emissions from individual vents of Etna volcano (Sicily), which we obtained using a permanent UV camera network. Observations were carried out in summer 2014, a period encompassing two eruptive episodes of the New South East Crater (NSEC) and a fissure‐fed eruption in the upper Valle del Bove. We demonstrate that our vent‐resolved SO2 flux time series allow capturing shifts in activity from one vent to another and contribute to our understanding of Etna's shallow plumbing system structure. We find that the fissure eruption contributed ~50,000 t of SO2 or ~30% of the SO2 emitted by the volcano during the 5 July to 10 August eruptive interval. Activity from this eruptive vent gradually vanished on 10 August, marking a switch of degassing toward the NSEC. Onset of degassing at the NSEC was a precursory to explosive paroxysmal activity on 11–15 August. PMID:27773952

  19. NOx and SO2 emission factors for Serbian lignite Kolubara

    Directory of Open Access Journals (Sweden)

    Jovanović Vladimir V.

    2012-01-01

    Full Text Available Emission factors are widely accepted tool for estimation of various pollutants emissions in USA and EU. Validity of emission factors is strongly related to experimental data on which they are based. This paper is a result of an effort to establish reliable NOx and SO2 emission factors for Serbian coals. The results of NOx and SO2 emissions estimations based on USA and EU emission factors from thermal power plants Nikola Tesla Obrenovac A and B utilizing the Serbian lignite Kolubara are compared with experimental data obtained during almost one decade (2000-2008 of emissions measurements. Experimental data are provided from regular annual emissions measurement along with operational parameters of the boiler and coal (lignite Kolubara ultimate and proximate analysis. Significant deviations of estimated from experimental data were observed for NOx, while the results for SO2 were satisfactory. Afterwards, the estimated and experimental data were plotted and linear regression between them established. Single parameter optimization was performed targeting the ideal slope of the regression line. Results of this optimization provided original NOx and SO2 emission factors for Kolubara lignite.

  20. Molecular Dynamics Investigation of Efficient SO2 Absorption by ...

    Indian Academy of Sciences (India)

    ANIRBAN MONDAL

    J. Chem. Sci. Vol. 129, No. 7, July 2017, pp. 859–872. c Indian Academy of Sciences. ... Ionic liquids are appropriate candidates for the absorption of acid gases such as SO2. Six anion- ... nificant number of task-specific ILs were designed and used to ...... investigation of a pilot-scale jet bubbling reactor for wet flue gas ...

  1. Heterogeneous oxidation of SO2 by O3-aged black carbon and its dithiothreitol oxidative potential.

    Science.gov (United States)

    Xu, Weiwei; Li, Qian; Shang, Jing; Liu, Jia; Feng, Xiang; Zhu, Tong

    2015-10-01

    Ozone (O3) is an important atmospheric oxidant. Black carbon (BC) particles released into the atmosphere undergo an aging process via O3 oxidation. O3-aged BC particles may change their uptake ability toward trace reducing gases such as SO2 in the atmosphere, leading to different environmental and health effects. In this paper, the heterogeneous reaction process between O3-aged BC and SO2 was explored via in-situ diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS). Combined with ion chromatography (IC), DRIFTS was used to qualitatively and quantitatively analyze the sulfate product. The results showed that O3-aged BC had stronger SO2 oxidation ability than fresh BC, and the reactive species/sites generated on the surface had an important role in the oxidation of SO2. Relative humidity or 254nm UV (ultraviolet) light illumination enhanced the oxidation uptake of SO2 on O3-aged BC. The oxidation potentials of the BC particles were detected via dithiothreitol (DTT) assay. The DTT activity over BC was decreased in the process of SO2 reduction, with the consumption of oxidative active sites. Copyright © 2015. Published by Elsevier B.V.

  2. Simultaneous removal of SO2 and NOX with ammonia absorbent in a packed column

    International Nuclear Information System (INIS)

    Jia, Yong; Du, Daqian; Zhang, Xinxi; Ding, Xilou; Zhong, Oin

    2013-01-01

    Catalytic oxidation of NO followed by simultaneous removal of SO 2 and NO X with ammonia is a promising method for control of coal-fired flue gas pollutants. We investigated simultaneous absorption of SO 2 and NO X in a packed column with ammonia, and found that SO 2 and NO X could promote absorption with each other in the process of simultaneous removal SO 2 and NO X . The removal efficiency of SO 2 and NO X was, respectively, about 98% and 70.9% at pH 5.5, temperature 323.15 K, SO 2 concentration 1,800x10 −6 , NO X concentration 400x10 −6 and m NO2 /m NO 1 in our experimental system. The experimental results also show that the formation of sulfite oxidized by reacting with dissolved NO 2 and the molar ratio of sulfite to total sulfur is more than 0.8 in the solution. Accordingly, the energy consumption for sulfite oxidation would be greatly reduced in the process of simultaneous desulfurization and denitrification with ammonia

  3. Simultaneous absorption of NO and SO2 into hexamminecobalt(II)/iodide solution.

    Science.gov (United States)

    Long, Xiang-Li; Xiao, Wen-De; Yuan, Wei-kang

    2005-05-01

    An innovative catalyst system has been developed to simultaneously remove NO and SO2 from combustion flue gas. Such catalyst system may be introduced to the scrubbing solution using ammonia solution to accomplish sequential absorption and catalytic oxidation of both NO and SO2 in the same reactor. When the catalyst system is utilized for removing NO and SO2 from the flue gas, Co(NH3)(6)2+ ions act as the catalyst and I- as the co-catalyst. Dissolved oxygen, in equilibrium with the residual oxygen in the flue gas, is the oxidant. The overall removal process is further enhanced by UV irradiation at 365 nm. More than 95% of NO is removed at a feed concentration of 250-900 ppm, and nearly 100% of SO2 is removed at a feed concentration of 800-2500 ppm. The sulfur dioxide co-existing in the flue gas is beneficial to NO absorption into hexamminecobalt(II)/iodide solution. NO and SO2 can be converted to ammonium sulfate and ammonium nitrate that can be used as fertilizer materials. The process described here demonstrates the feasibility of removing SO2 and NO simultaneously only by retrofitting the existing wet ammonia flue-gas-desulfurization (FGD) scrubbers.

  4. Application of DBD and DBCD in SO2 removal

    International Nuclear Information System (INIS)

    Sun Yanzhou; Henan Polytechnic Univ., Jiaozuo; Qiu Yuchang; Yuan Xingcheng; Yu Fashan

    2004-01-01

    The dielectric barrier corona discharge (DBCD) in a wire-cylinder configuration and the dielectric barrier discharge (DBD) in a coaxial cylinder configuration are studied. The discharge current in DBD has a higher pulse amplitude than in DBCD. The dissipated power and the gas-gap voltage are calculated by analyzing the measured Lissajous figure. With the increasing applied voltage, the energy utilization factor for SO 2 removal increases in DBCD but decreases in DBD because of the difference in their electric field distribution. Experiments of SO 2 removal show that in the absence of NH 3 the energy utilization factor can reach 31 g/k Wh in DBCD and 39 g/kWh in DBD. (authors)

  5. 76 FR 66925 - Guidance for 1-Hour SO2

    Science.gov (United States)

    2011-10-28

    ...The EPA is announcing an extension of the public comment period for its draft non-binding guidance titled, ``Guidance for 1-Hour SO2 SIP Submissions.'' The draft of the guidance document is currently on the EPA's Web site. The EPA is extending the comment period for an additional 30-day period and invites public comments on this guidance during this period. The EPA plans to issue an updated version of the guidance after reviewing timely submitted comments.

  6. Coal sulfur-premium models for SO2 allowance valuation

    International Nuclear Information System (INIS)

    Henry, J.B. II; Radulski, D.R.; Ellingson, E.G.; Engels, J.P.

    1995-01-01

    Clean Air Capital Markets, an investment bank structuring SO 2 Allowance transactions, has designed two allowance value models. The first forecasts an equilibrium allowance value based on coal supply and demand. The second estimates the sulfur premium of all reported coal deliveries to utilities. Both models demonstrate that the fundamental allowance value is approximately double current spot market prices for small volumes of off-system allowances

  7. Soil acidification in China: is controlling SO2 emissions enough?

    Science.gov (United States)

    Zhao, Yu; Duan, Lei; Xing, Jia; Larssen, Thorjorn; Nielsen, Chris P; Hao, Jiming

    2009-11-01

    Facing challenges of increased energy consumption and related regional air pollution, China has been aggressively implementing flue gas desulfurization (FGD) and phasing out small inefficient units in the power sector in order to achieve the national goal of 10% reduction in sulfur dioxide (SO(2)) emissions from 2005 to 2010. In this paper, the effect of these measures on soil acidification is explored. An integrated methodology is used, combining emission inventory data, emission forecasts, air quality modeling, and ecological sensitivities indicated by critical load. National emissions of SO(2), oxides of nitrogen (NO(X)), particulate matter (PM), and ammonia (NH(3)) in 2005 were estimated to be 30.7, 19.6, 31.3, and 16.6 Mt, respectively. Implementation of existing policy will lead to reductions in SO(2) and PM emissions, while those of NO(X) and NH(3) will continue to rise, even under tentatively proposed control measures. In 2005, the critical load for soil acidification caused by sulfur (S) deposition was exceeded in 28% of the country's territory, mainly in eastern and south-central China. The area in exceedance will decrease to 26% and 20% in 2010 and 2020, respectively, given implementation of current plans for emission reductions. However, the exceedance of the critical load for nitrogen (N, combining effects of eutrophication and acidification) will double from 2005 to 2020 due to increased NO(X) and NH(3) emissions. Combining the acidification effects of S and N, the benefits of SO(2) reductions during 2005-2010 will almost be negated by increased N emissions. Therefore abatement of N emissions (NO(X) and NH(3)) and deposition will be a major challenge to China, requiring policy development and technology investments. To mitigate acidification in the future, China needs a multipollutant control strategy that integrates measures to reduce S, N, and PM.

  8. SO2 Spectroscopy with A Tunable UV Laser

    Science.gov (United States)

    Morey, W. W.; Penney, C. M.; Lapp, M.

    1973-01-01

    A portion of the fluorescence spectrum of SO2 has been studied using a narrow wavelength doubled dye laser as the exciting source. One purpose of this study is to evaluate the use of SO2 resonance re-emission as a probe of SO2 in the atmosphere. When the SO2 is excited by light at 300.2 nm, for example, a strong reemission peak is observed which is Stokes-shifted from the incident light wavelength by the usual Raman shift (the VI symmetric vibration frequency 1150.5/cm ). The intensity of this peak is sensitive to small changes (.01 nm) in the incident wavelength. Measurements of the N2 quenching and self quenching of this re-emission have been obtained. Preliminary analysis of this data indicates that the quenching is weak but not negligible. The dye laser in our system is pumped by a pulsed N2 laser. Tuning 'and spectral narrowing are accomplished using a telescope-echelle grating combination. In a high power configuration the resulting pulses have a spectral width of about 5 x 10(exp -3) nm and a time duration of about 6 nsec. The echelle grating is rotated by a digital stepping motor, such that each step shifts the wavelength by 6 x 10(exp -4) nm. In addition to the tunable, narrow wavelength uv source and spectral analysis of the consequent re-emission, the system also provides time resolution of the re-emitted light to 6 nsec resolution. This capability is being used to study the lifetime of low pressure S02 fluorescence at different wavelengths and pressures.

  9. Forecasting the market for SO2 emission allowances under uncertainty

    International Nuclear Information System (INIS)

    Hanson, D.; Molburg, J.; Fisher, R.; Boyd, G.; Pandola, G.; Lurie, G.; Taxon, T.

    1991-01-01

    This paper deals with the effects of uncertainty and risk aversion on market outcomes for SO 2 emission allowance prices and on electric utility compliance choices. The 1990 Clean Air Act Amendments (CAAA), which are briefly reviewed here, provide for about twice as many SO 2 allowances to be issued per year in Phase 1 (1995--1999) than in Phase 2. Considering the scrubber incentives in Phase 1, there is likely to be substantial emission banking for use in Phase 2. Allowance prices are expected to increase over time at a rate less than the return on alternative investments, so utilities which are risk neutral, or potential speculators in the allowance market, are not expected to bank allowances. The allowances will be banked by utilities that are risk averse. The Argonne Utility Simulation Model (ARGUS2) is being revised to incorporate the provisions of the CAAA acid rain title and to simulate SO 2 allowance prices, compliance choices, capacity expansion, system dispatch, fuel use, and emissions using a unit level data base and alternative scenario assumptions. 1 fig

  10. Low SO2 Emission Preheaters for Cement Production

    DEFF Research Database (Denmark)

    Rasmussen, Martin Hagsted

    in this thesis has been to produce CaO with a large surface area in order to increase the absorption of SO2. For this purpose flash calcination of CaCO3, calcination under vacuum, calcination in a fixed bed and a fluid bed has been tested between 650 °C and 850 °C. The results showed that flash calcination...... at low temperatures resulted in the largest surface area, about 140 m2/g CaO. The material produced from all of the methods was a mixture of CaO and CaCO3, meaning that the material was only partly calcined, but with the particle surface area being comprised by CaO. One focus in this thesis...... against SO2 data from five full-scale plants, showing satisfactory results in two cases. An investigation of the parameters showed that it was possible to obtain satisfactory results in four out of five cases by allowing the CaCO3 surface area available for SO2 absorption to be about 4 m2/g instead...

  11. Persistent explosive activity at Stromboli investigated with OP-FTIR and SO2 cameras

    Science.gov (United States)

    Burton, M. R.; La Spina, A.; Sawyer, G. M.; Harris, A. J.

    2012-12-01

    Stromboli volcano in Italy exhibits what is perhaps one of the most well-known examples of cyclic activity, in the form of its regular explosions, which send a few m3 of material 100-200 m into the air every 10-20 minutes. Recent developments in measurements of volatile release from Stromboli using a series of novel approaches have allowed this cyclic behaviour to be examined in detail. In particular, the use of an automated OP-FTIR has revealed unprecedented detail in the dynamics of degassing from individual craters at the summit of Stromboli. Furthermore, the variations in composition of explosive degassing from Stromboli demonstrate a deep source ~2 km for the gas slugs which produce explosions at this volcano, in contrast to the commonly-held view that gas coalescence at shallow depth is responsible for the behaviour. The SO2 camera has revealed fascinating new details on the dynamics of degassing at Stromboli, and has allowed direct quantification of the amount of gas released during explosions and through quiescent degassing. The remarkable observation that 99% of degassing takes place quiescently, and that the explosions, whilst apparently more significant, are in fact a secondary process compared with the mass and energy involved in background, quiet processes. The new insight that the explosions are actually only a relatively minor aspect of the activity (in terms of mass and energy) actually makes the regularity of the cyclic explosive activity still more remarkable. In this paper we present a detailed overview of the state of the art of our understanding of cyclic explosive activity at Stromboli volcano from the perspective of recent advances in geochemical monitoring of the gas emissions. We also report initial results from a multidisciplinary campaign on Stromboli which utilised both OP-FTIR and SO2 camera techniques.

  12. Temperature impact on SO2 removal efficiency by ammonia gas scrubbing

    International Nuclear Information System (INIS)

    He Boshu; Zheng Xianyu; Wen Yan; Tong Huiling; Chen Meiqian; Chen Changhe

    2003-01-01

    Emissions reduction in industrial processes, i.e. clean production, is an essential requirement for sustainable development. Fossil fuel combustion is the main emission source for gas pollutants, such as NO X , SO 2 and CO 2 , and coal is now a primary energy source used worldwide with coal combustion being the greatest atmospheric pollution source in China. This paper analyzes flue gas cleaning by ammonia scrubbing (FGCAS) for power plants to remove gaseous pollutants, such as NO X , SO 2 and CO 2 , and presents the conceptual zero emission design for power plants. The byproducts from the FGCAS process can be used in agriculture or for gas recovery. Experimental results presented for SO 2 removal from the simulated flue gas in a continuous flow experiment, which was similar to an actual flue gas system, showed that the effectiveness of the ammonia injection or scrubbing depends on the temperature. The FGCAS process can effectively remove SO 2 , but the process temperature should be below 60 deg. C or above 80 deg. C for SO 2 reduction by NH 3 scrubbing

  13. Simultaneous removal of SO2, NO and Hg0 from flue gas by ferrate (VI) solution

    International Nuclear Information System (INIS)

    Zhao, Yi; Han, Yinghui; Guo, Tianxiang; Ma, Tianzhong

    2014-01-01

    Simultaneously removing SO 2 , NO and Hg 0 from flue gas was examined by ferrate (VI) solution at a bubbling reactor. The removal efficiencies of 100% for SO 2 , 64.8% for NO and 81.4% for Hg 0 were achieved respectively, under the optimum experimental conditions, in which concentration of ferrate (VI) solution was 0.25 mmol/L, solution pH was 8.0, flue gas flow rate was 1 L/min and reaction temperature was 320 K. Based on the discussions of the ferrate (VI) solution characteristics, the comparisons of the standard electrode potential (E 0 ) of ferrate (VI) solution with E 0 values of reactant, and the analysis of the reaction products, a mechanism of simultaneous removal was proposed. In the process of simultaneous removal, FeO 4 2− and HFeO 4 − as the dominant species of ferrate (VI), could rapidly oxidize SO 2 , NO, and Hg 0 into SO 4 2− , NO 3 − and Hg 2+ . - Highlights: • Prepared ferrate (VI) absorbent has excellent property of removing SO 2 , NO and Hg 0 . • 100% of SO 2 , 63.8% of NO and 83.6% of Hg 0 were simultaneously removed. • The simultaneous removal mechanism of SO 2 , NO and Hg 0 was proposed

  14. Next-Generation Aura/OMI NO2 and SO2 Products

    Science.gov (United States)

    Krotkov, Nickolay; Yang, Kai; Bucsela, Eric; Lamsal, Lok; Celarier, Edward; Swartz, William; Carn, Simon; Bhartia, Pawan; Gleason, James; Pickering, Ken; hide

    2011-01-01

    The measurement of both SO2 and NO2 gases are recognized as an essential component of atmospheric composition missions. We describe current capabilities and limitations of the operational Aura/OMI NO2 and SO2 data that have been used by a large number of researchers. Analyses of the data and validation studies have brought to light a number of areas in which these products can be expanded and improved. Major improvements for new NASA standard (SP) NO2 product include more accurate tropospheric and stratospheric column amounts, along with much improved error estimates and diagnostics. Our approach uses a monthly NO2 climatology based on the NASA Global Modeling Initiative (GMI) chemistry-transport model and takes advantage of OMI data from cloudy scenes to find clean areas where the contribution from the trap NO2 column is relatively small. We then use a new filtering, interpolation and smoothing techniques for separating the stratospheric and tropospheric components of NO2, minimizing the influence of a priori information. The new algorithm greatly improves the structure of stratospheric features relative to the original SP. For the next-generation OMI SO2 product we plan to implement operationally the offline iterative spectral fitting (ISF) algorithm and re-process the OMI Level-2 SO2 dataset using a priori SO2 and aerosol profiles, clouds, and surface reflectivity appropriate for observation conditions. This will improve the ability to detect and quantify weak tropospheric SO2 loadings. The new algorithm is validated using aircraft in-situ data during field campaigns in China (2005 and 2008) and in Maryland (Frostburg, 2010 and DISCOVER-AQ in July 2011). The height of the SO2 plumes will also be estimated for high SO2 loading cases (e.g., volcanic eruptions). The same SO2 algorithm will be applied to the data from OMPS sensor to be launched on NPP satellite later this year. The next-generation NO2 and SO2 products will provide critical information (e

  15. Sulfur Dioxide (SO2) Primary NAAQS Review: Integrated Review Plan - Advisory with CASAC

    Science.gov (United States)

    The SO2 Integrated Review Plan is the first document generated as part of the National Ambient Air Quality Standards (NAAQS) review process. The Plan presents background information, the schedule for the review, the process to be used in conducting the review, and the key policy-...

  16. Impediments to markets for SO2 emission allowances

    International Nuclear Information System (INIS)

    Walsh, M.; Ramesh, V.C.; Ghosh, K.

    1996-01-01

    The Clean Air Act (CAA) of 1990 imposed tighter limits on allowed emissions from electric utilities. The CAA also introduced an innovative SO 2 market mechanism to help lower the cost of compliance. The annual Environmental Protection Agency (EPA) auctions of emission allowances intended to help usher in the market mechanisms for trading allowances. In that respect, the results have been mixed. A full fledged market for emission allowances has been slow to emerge. Starting with a detailed study of the EPA auctions to date, this paper analyzes and discusses some of the reasons for this slow development

  17. Effect of SO2 Dry Deposition on Porous Dolomitic Limestones

    Directory of Open Access Journals (Sweden)

    Florica Doroftei

    2010-01-01

    Full Text Available The present study is concerned with the assessment of the relative resistance of a monumental dolomitic limestone (Laspra – Spain used as building material in stone monuments and submitted to artificial ageing by SO2 dry deposition in the presence of humidity. To investigate the protection efficiency of different polymeric coatings, three commercially available siloxane-based oligomers (Lotexan-N, Silres BS 290 and Tegosivin HL 100 and a newly synthesized hybrid nanocomposite with silsesquioxane units (TMSPMA were used. A comparative assessment of the data obtained in this study underlines that a better limestone protection was obtained when treated with the hybrid nanocomposite with silsesquioxane units.

  18. The thermochromic behavior of aromatic amine-SO2 charge transfer complexes

    Science.gov (United States)

    Monezi, Natália M.; Borin, Antonio C.; Santos, Paulo S.; Ando, Rômulo A.

    2017-02-01

    The distinct thermochromism observed in solutions containing N,N-dimethylaniline (DMA) and N,N-diethylaniline (DEA) and SO2 was investigated by resonance Raman spectroscopy in a wide range of temperatures. The results indicate in addition to the charge transfer (CT) complexes DMA-SO2 and DEA-SO2, the presence of collision complexes involving the CT complexes and excess DMA and DEA molecules. The latter in fact is the chromophore responsible for the long wavelength absorption originating the color. The Raman signature of the collision complex was attributed to the distinct enhancement of a band at 1140 cm- 1 assigned to νs(SO2), in contrast to the same mode in the 1:1 complex at 1115 cm- 1. The intensity of such band, assigned to the collision complex is favored at high temperatures and depends on the steric hindrance associated to amines, as well as the SO2 molar fraction. Quantum chemical calculations based on time-dependent density functional theory (TDDFT) support the proposed interpretation.

  19. Impact of Manufacturing Transfer on SO2 Emissions in Jiangsu Province, China

    Directory of Open Access Journals (Sweden)

    Ying Peng

    2016-05-01

    Full Text Available The impact of manufacturing transfer in Jiangsu province, China, on the spatial-temporal variations of SO2 emissions is investigated using estimated sector-specific SO2 emissions, and emissions in the different transfer-in and transfer-out regions were quantified during 2000–2011. Our results show that SO2 emissions had undergone three phases: an increase in the period of 2000–2005, a rapid decline in 2005–2008 and a slow decline in 2008–2011. Emissions from the south dominated the total emissions in the province. Cleaner production generally contributed to the reduced emissions, but rather, at the industrial scale. Pollution abatement was occasional and industrial structure was negligible in some years. The three phases also coincided with the three periods of the manufacturing transfer: transferred to the south from outside the province during 2000–2005, to the central from the south within the province during 2005–2008 and to the north from the south or partly from the inner central within the province during 2008–2011. With the manufacturing transfer, SO2 emission magnitudes and distributions were also changed. In the south, −12.36 and −5.62 Mt of SO2 emissions were transferred out during 2005–2008 and 2008–2011, respectively. Forty-three-point-four percent and 56.4% of the SO2 emissions in the south were transferred to the central and north during 2005–2008, respectively. The north region received 77.7% and 22.1% of SO2 emissions from the south and the central region during 2008–2011, respectively. The paper reveals that structure adjustments should be executed in a timely manner in the manufacturing transfer-in process so that the transfer-in regions can benefit from the economic boom without bearing a deteriorated environment.

  20. Democratizing Process Innovation? On Citizen Involvement in Public Sector BPM

    Science.gov (United States)

    Niehaves, Björn; Malsch, Robert

    ‘Open Innovation’ has been heavily discussed for product innovations; however, an information systems (IS) perspective on ‘process innovation’ has not yet been taken. Analyzing the example of the public sector in Germany, the paper seeks to investigate the factors that hinder and support ‘open process innovation’, a concept we define as the involvement of citizens in business process management (BPM) activities. With the help of a quantitative study (n=358), six factors are examined for their impact on citizen involvement in local government BPM initiatives. The results show that citizen involvement in reform processes is not primarily motivated by the aim of cost reduction, but rather related to legitimacy reasons and the intent to increase employee motivation. Based on these findings, implications for (design) theory and practice are discussed: Instead of detailed collaborative business processes modeling, the key of citizen involvement in public sector BPM lies in communication and mutual understanding.

  1. Experimental and simulation studies of iron oxides for geochemical fixation of CO2-SO2 gas mixtures

    Science.gov (United States)

    Garcia, Susana; Rosenbauer, Robert J.; Palandri, James; Maroto-Valer, M. Mercedes

    2011-01-01

    Iron-bearing minerals are reactive phases of the subsurface environment and could potentially trap CO2–SO2gas mixtures derived from fossil fuel combustion processes by their conversion to siderite (FeCO3) and dissolved sulfate. Changes in fluid and mineral compositions resulting from reactions, involving the co-injection of SO2 with CO2 were observed both theoretically and experimentally. Experiments were conducted with a natural hematite (α-Fe2O3) sample. A high pressure-high temperature apparatus was used to simulate conditions in geologic formations deeper than 800 m, where CO2 is in the supercritical state. Solid samples were allowed to react with a NaCl–NaOH brine and SO2-bearing CO2-dominated gas mixtures. The predicted equilibrium mineral assemblage at 100 °C and 250 bar became hematite, dawsonite (NaAl(OH)2CO3), siderite (FeCO3) and quartz (SiO2). Experimentally, siderite and dawsonite, derived from the presence of kaolinite (Al2Si2O5(OH)4) in the parent material, were present in residual solids at longer reaction time intervals, which agreed well with results from the modelling work.

  2. The SO2 pollution in Madrid: Pt. 2

    International Nuclear Information System (INIS)

    Finzi, G.; Garcia, R.; Hernandez, E.

    1983-01-01

    In this work, two different stochastic models will be considered, both oriented to the real-time forecast of daily SO 2 pollution in Madrid. The first one a ''black-box'' model, in which the input-output transfer function is identified by means of the methodology given by Box and Jenkins. The second one is a ''grey-box'' model with a simple reasonable structure in accordance with the physical laws of the phenomena. Moreover, its parameters can assume different values according to the different meteorological synoptic classes defined in part I. The comparison between the performance of the two models shows that the second one is more effective in predicting the critical pollution values

  3. Anthropogenic SO2/NOx committee--current status

    International Nuclear Information System (INIS)

    Benkovitz, C.M.

    1993-04-01

    Current activities of the Anthropogenic SO 2 /NO x Committee center around the compilation of Version 1 of the GEIA inventories. These inventories will be based on the GEIA-specified 1 degrees by 1 degrees grid (lower left corner at 180 degrees W/90 degrees S, west to east and south to north), reflect 1985 emissions and consist of two data sets: Version 1A inventories with annual emissions at one level and Version 1B inventories with seasonal emissions, two vertical levels (defined at 100 m) and sectoral split information. The basic information used for both versions of the GEIA inventories will be identical; i.e., emissions totals across both inventories will be the same. Work is being carried out in two complementary working groups; Carmen Benkovitz, Brookhaven National Laboratory, Upton, NY, USA heads the work on the annual inventory, Eva Voldner, Atmospheric Environment Services, Canada and Trevor Scholtz, ORTECH International, Canada, head the work on the seasonal inventory

  4. Simultaneous removal of NO and SO2 using vacuum ultraviolet light (VUV)/heat/peroxymonosulfate (PMS).

    Science.gov (United States)

    Liu, Yangxian; Wang, Yan; Wang, Qian; Pan, Jianfeng; Zhang, Jun

    2018-01-01

    Simultaneous removal process of SO 2 and NO from flue gas using vacuum ultraviolet light (VUV)/heat/peroxymonosulfate (PMS) in a VUV spraying reactor was proposed. The key influencing factors, active species, reaction products and mechanism of SO 2 and NO simultaneous removal were investigated. The results show that vacuum ultraviolet light (185 nm) achieves the highest NO removal efficiency and yield of and under the same test conditions. NO removal is enhanced at higher PMS concentration, light intensity and oxygen concentration, and is inhibited at higher NO concentration, SO 2 concentration and solution pH. Solution temperature has a double impact on NO removal. CO 2 concentration has no obvious effect on NO removal. and produced from VUV-activation of PMS play a leading role in NO removal. O 3 and ·O produced from VUV-activation of O 2 also play an important role in NO removal. SO 2 achieves complete removal under all experimental conditions due to its very high solubility in water and good reactivity. The highest simultaneous removal efficiency of SO 2 and NO reaches 100% and 91.3%, respectively. Copyright © 2017 Elsevier Ltd. All rights reserved.

  5. Energy consumption of SO2 removal from humid air under electron beam and electric field influence

    International Nuclear Information System (INIS)

    Nichipor, H.; Radjuk, E.; Chmielewski, A.G.; Zimek, Z.

    1998-01-01

    The kinetic of SO 2 oxidation in humid air under influence of electron beam and electrical field was investigated by computer simulation method in steady state and pulse mode. SO 2 oxidation process was stimulated by radical and ion reactions. The calculation model has included 46 different particles and 160 chemical reactions. Gas mixture containing 1000 ppm of SO 2 concentration was investigated at temperature T=67 deg. C and pressure p=1 at. Water content was within the range 2-12%. Electron beam parameters were as follows: average beam current density 0.0032-3,2 mA/cm 2 , pulse duration 400 μs, repetition rate 50 Hz. Electrical field density was E/n =10 -15 Vcm 2 . Electrical pulse duration was changed within the range 5 x10 -7 -10 -5 s. The influence of the parameters of synchronized electron beam and electrical field pulses on energy deposition was under consideration. Energy cost of SO 2 removal on 90% level was estimated in steady state and pulse modes. It was found that total electron beam and electrical field energy losses in pulse mode are 6 times lower to compare with steady state conditions. The optimum of electrical field pulse duration from point of view minimum energy cost of SO 2 removal was found for different electron beam pulse current levels

  6. Reactive adsorption of SO2 on activated carbons with deposited iron nanoparticles.

    Science.gov (United States)

    Arcibar-Orozco, Javier A; Rangel-Mendez, J Rene; Bandosz, Teresa J

    2013-02-15

    The effect of iron particle size anchored on the surface of commercial activated carbon on the removal of SO(2) from a gas phase was studied. Nanosize iron particles were deposited using forced hydrolysis of FeCl(3) with or without H(3)PO(4) as a capping agent. Dynamic adsorption experiments were carried out on either dry or pre-humidified materials and the adsorption capacities were calculated. The surface of the initial and exhausted materials was extensively characterized by microscopic, porosity, thermogravimetric and surface chemistry. The results indicate that the SO(2) adsorption capacity increased two and half times after the prehumidification process owing to the formation of H(2)SO(4) in the porous system. Iron species enhance the SO(2) adsorption capacity only when very small nanoparticles are deposited on the pore walls as a thin layer. Large iron nanoparticles block the ultramicropores decreasing the accessibility of the active sites and consuming oxygen that rest adsorption centers for SO(2) molecules. Iron nanoparticles of about 3-4 nm provide highly dispersed adsorption sites for SO(2) molecules and thus increase the adsorption capacity of about 80%. Fe(2)(SO(4))(3) was detected on the surface of exhausted samples. Copyright © 2012 Elsevier B.V. All rights reserved.

  7. SO2 Release as a Consequence of Alternative Fuel Combustion in Cement Rotary Kiln Inlets

    DEFF Research Database (Denmark)

    Cortada Mut, Maria del Mar; Nørskov, Linda Kaare; Glarborg, Peter

    2015-01-01

    The combustion of alternative fuels in direct contact with the bed material of the rotary kiln may cause local reducing conditions and, subsequently, decomposition of sulfates from cement raw materials, increasing the SO2 concentration in the gas phase. The decomposition of sulfates increases...... the sulfur circulation and may be problematic because high sulfur circulation can cause sticky material buildup, affecting the process operation of the cement kiln system. The SO2 release from cement raw materials during combustion of pine wood and tire rubber has been studied experimentally in a high...

  8. Retrieve of atmospheric SO2 and O3 columns in the UV region using mobile DOAS

    International Nuclear Information System (INIS)

    Galicia, R.; La Rosa, J. de la; Stolik, S.

    2012-01-01

    We present the use of a passive DOAS system to retrieve SO2 and O3 columns emitted by industrial chimneys. It works with software built in LabVIEW and running with a PC linked to mini spectrometer and GPS. The system uses the sun light as light source, a telescope a fiber optic, a mini-spectrometer and a GPS. The spectrometer and the GPS are linked to a PC where the system is controlled and where all data are processed to retrieve the SO2 and O3 slant columns. (Author)

  9. A Method for the Simultaneous Cleansing of H2S and SO2

    Directory of Open Access Journals (Sweden)

    Dzhamal R. Uzun

    2016-01-01

    Full Text Available A method for the simultaneous electrochemical purification of hydrogen sulfide and sulfur dioxide from sea water or industrial wastes is proposed. Fundamentally the method is based on the electrochemical affinity of the pair H2S and SO2. The reactions (oxidation of H2S and reduction of SO2 proceed on а proper catalyst in a flow reactor, without an external power by electrochemical means. The partial curves of oxidation of H2S and reduction of SO2 have been studied electrochemically on different catalysts. Following the additive principle the rate of the process has been found by intersection of the curves. The overall process rate has been studied in a flow type reactor. Similar values of the process rate have been found and these prove the electrochemical mechanism of the reactions. As a result the electrochemical method at adequate conditions is developed. The process is able to completely convert the initial reagents (concentrations CH2S, SO2=0, which is difficult given the chemical kinetics.

  10. Vulcamera: a program for measuring volcanic SO2 using UV cameras

    Directory of Open Access Journals (Sweden)

    Alessandro Aiuppa

    2011-06-01

    Full Text Available We report here on Vulcamera, a stand-alone program for the determination of volcanic SO2  fluxes using ultraviolet cameras. The code enables field image acquisition and all the required post-processing operations.

  11. Making a market for SO2 emissions trading

    International Nuclear Information System (INIS)

    Solomon, B.D.; Rose, K.

    1992-01-01

    Under the innovative, market-based approach to acid rain control included in the Clean Air Act amendments of 1990 (CAAA), sulfur dioxide emission allowances allocated to existing electric utility sources of these emissions can be used by utilities, banked for future use, or sold or traded to other users. Most power plants that burn fossil fuels will need to obtain an adequate supply of allowances from the market of EPA-sponsored auctions to cover their future emissions. This article addresses the respective roles of regulators and the private sector in facilitating a market for SO 2 emission allowances. In previous work, the authors have argued that state public utility commissions should seize the opportunity to encourage utilities to facilitate the allowance market. Yet it is the nature of new markets that many potential participants (including regulators) are risk-averse and wait for others to make the first move. Taken to the extreme, such behavior is a prescription for failure. The authors stated purpose is both to offer a perspective on how to make a market for what was previously considered an externality, as well as to stimulate debate among the various players and elicit better ideas. In fact, much more may be at stake. The success or failure of the emissions trading program could well set a benchmark for future environmental protection efforts in the US and globally

  12. SO2 policy and input substitution under spatial monopoly

    International Nuclear Information System (INIS)

    Gerking, Shelby; Hamilton, Stephen F.

    2010-01-01

    Following the U.S. Clean Air Act Amendments of 1990, electric utilities dramatically increased their utilization of low-sulfur coal from the Powder River Basin (PRB). Recent studies indicate that railroads hauling PRB coal exercise a substantial degree of market power and that relative price changes in the mining and transportation sectors were contributing factors to the observed pattern of input substitution. This paper asks the related question: To what extent does more stringent SO 2 policy stimulate input substitution from high-sulfur coal to low-sulfur coal when railroads hauling low-sulfur coal exercise spatial monopoly power? The question underpins the effectiveness of incentive-based environmental policies given the essential role of market performance in input, output, and abatement markets in determining the social cost of regulation. Our analysis indicates that environmental regulation leads to negligible input substitution effects when clean and dirty inputs are highly substitutable and the clean input market is mediated by a spatial monopolist. (author)

  13. Debunking the myths: Natural gas and SO2 allowance solutions

    International Nuclear Information System (INIS)

    Roberts, G.D. Jr.

    1993-01-01

    During the decade of the 1990's and beyond, natural gas is expected to be the fuel of choice for a significant portion of new generation capacity. Natural gas already enjoys a greater than 50% market share as a fuel source in the non-regulated cogeneration and Independent Power Producer market. With the new administration in Washington, increased environmental focus will likely increase the attractiveness of natural gas based capacity expansions. While these various issues may appear to contribute to making this decade, the decade for natural gas, there are a number of challenges that must be met if the natural gas and power generation industries are going to satisfy the ever increasing needs of the marketplace. These challenges include: (1) myths of natural gas supply availability, (2) transportation and operational coordination issues, (3) uncertainty of price and reliability, and (4) natural gas for NO x and SO 2 compliance. The author believes that these challenges are actively being met and that there are existing solutions already being offered and incorporated into contracts by natural gas suppliers. The focus of this paper is how electric utilities need to become comfortable with the new natural gas industry and how services can be structured to meet these challenges of serving the electric market requirements

  14. DSCOVR/EPIC observations of SO2 reveal dynamics of young volcanic eruption clouds

    Science.gov (United States)

    Carn, S. A.; Krotkov, N. A.; Taylor, S.; Fisher, B. L.; Li, C.; Bhartia, P. K.; Prata, F. J.

    2017-12-01

    Volcanic emissions of sulfur dioxide (SO2) and ash have been measured by ultraviolet (UV) and infrared (IR) sensors on US and European polar-orbiting satellites since the late 1970s. Although successful, the main limitation of these observations from low Earth orbit (LEO) is poor temporal resolution (once per day at low latitudes). Furthermore, most currently operational geostationary satellites cannot detect SO2, a key tracer of volcanic plumes, limiting our ability to elucidate processes in fresh, rapidly evolving volcanic eruption clouds. In 2015, the launch of the Earth Polychromatic Imaging Camera (EPIC) aboard the Deep Space Climate Observatory (DSCOVR) provided the first opportunity to observe volcanic clouds from the L1 Lagrange point. EPIC is a 10-band spectroradiometer spanning UV to near-IR wavelengths with two UV channels sensitive to SO2, and a ground resolution of 25 km. The unique L1 vantage point provides continuous observations of the sunlit Earth disk, from sunrise to sunset, offering multiple daily observations of volcanic SO2 and ash clouds in the EPIC field of view. When coupled with complementary retrievals from polar-orbiting UV and IR sensors such as the Ozone Monitoring Instrument (OMI), the Ozone Mapping and Profiler Suite (OMPS), and the Atmospheric Infrared Sounder (AIRS), we demonstrate how the increased observation frequency afforded by DSCOVR/EPIC permits more timely volcanic eruption detection and novel analyses of the temporal evolution of volcanic clouds. Although EPIC has detected several mid- to high-latitude volcanic eruptions since launch, we focus on recent eruptions of Bogoslof volcano (Aleutian Islands, AK, USA). A series of EPIC exposures from May 28-29, 2017, uniquely captures the evolution of SO2 mass in a young Bogoslof eruption cloud, showing separation of SO2- and ice-rich regions of the cloud. We show how analyses of these sequences of EPIC SO2 data can elucidate poorly understood processes in transient eruption

  15. Investigating Individuals' Intention to be Involved in Knowledge Management Process

    OpenAIRE

    M. J.M. Razi; N. S.A. Karim

    2011-01-01

    Problem statement: Implementation of Knowledge Management (KM) process in organizations is considered as essential to be competitive in the present competitive world. Though the modern KM practices highly depend on technology, individuals (organizational members) intention to be involved in KM process plays a major role in the success. Hence, the evaluation of individuals intention is deemed as significant before the actual implementation of KM process in organizations. Nevertheless, inadequa...

  16. Aura OMI Observations of Global SO2 and NO2 Pollution from 2005 to 2013

    Science.gov (United States)

    Krotkov, Nickolay; Li, Can; Lamsal, Lok; Celarier, Edward; Marchenko, Sergey; Swartz, William H.; Bucsela, Eric; Fioletov, Vitali; McLinden, Chris; Joiner, Joanna; hide

    2014-01-01

    The Ozone Monitoring Instrument (OMI), a NASA partnership with the Netherlands and Finland, flies on the NASA Aura satellite and uses reflected sunlight to measure the two critical atmospheric trace gases: nitrogen dioxide (NO2) and sulfur dioxide (SO2) characterizing daily air quality. Both gases and the secondary pollutants they produce (particulate matter, PM2.5, and tropospheric ozone) are USEPA designated criteria pollutants, posing serious threats to human health and the environment (e.g., acid rain, plant damage and reduced visibility). Our group at NASA GSFC has developed and maintained OMI standard SO2 and NO2 data products. We have recently released an updated version of the standard NO2 L2 and L3 products (SP v2.1) and continue improving the algorithm. We are currently in the process of releasing next generation pollution SO2 product, based on an innovative Principal Component Analysis (PCA) algorithm, which greatly reduces the noise and biases. These new standard products provide valuable datasets for studying anthropogenic pollution on local to global scales. Here we highlight some of the OMI observed changes in air quality over several regions. Over the US average NO2 and SO2 pollution levels had decreased dramatically as a result of both technological improvements (e.g., catalytic converters on cars) and stricter regulations of emissions. We see continued decline in pollution over Europe. Over China OMI observed an increase of about 60 percent in NO2 pollution between 2005 and 2013, despite a temporal reversal of the growing trend due to both 2008 Olympic Games and the economic recession in 2009. Chinese SO2 pollution seems to have stabilized since peaking in 2007, probably due to government efforts to curb SO2 emissions from the power sector. We have also observed large increases in both SO2 and NO2 pollution particularly in Eastern India where a number of large new coal power plants had been built in recent years. We expect that further

  17. Infrasound and SO2 Observations of the 2011 Explosive Eruption of Nabro Volcano, Eritrea

    Science.gov (United States)

    Fee, D.; Carn, S. A.; Prata, F.

    2011-12-01

    SO2 measurements to investigate the relationship between degassing and infrasound, and to speculate on possible eruption source mechanisms. This example, in addition to other recent work, demonstrates the utility of using regional and global infrasound arrays to characterize explosive volcanic eruptions, particularly in remote and poorly monitored regions. Further, comparison of SO2 emissions and infrasound lends insight into degassing processes and shows the potential to use infrasound as a real-time, remote means to detect hazardous emissions.

  18. Secretory processes involved in the formation of milk

    International Nuclear Information System (INIS)

    Knutsson, P.G.

    1976-01-01

    Current knowledge on milk formation is reviewed. Emphasis is given to sites of formation of protein, fat and lactose, and transfer of these compounds into the alveolar lumen. Further, the formation of the water phase of milk is thoroughly discussed, and evidence presented that milk formation includes both secretory and re-absorptive processes as well as diffusion. A short presentation of colostrum formation is included. Neither biochemical processes involved in synthesis of organic compounds nor mammary gland endocrinology are discussed. (author)

  19. Thermodynamic modeling of NH_3-CO_2-SO_2-K_2SO_4-H_2O system for combined CO_2 and SO_2 capture using aqueous NH_3

    International Nuclear Information System (INIS)

    Qi, Guojie; Wang, Shujuan

    2017-01-01

    Highlights: • A new application of aqueous NH_3 based combined CO_2 and SO_2 process was proposed. • A thermodynamic model simulated the heat of absorption and the K_2SO_4 precipitation. • The CO_2 content can be regenerated in a stripper with lower heat of desorption. • The SO_2 content can be removed by K_2SO_4 precipitation from the lean NH_3 solvent. - Abstract: A new application of aqueous NH_3 based post-combustion CO_2 and SO_2 combined capture process was proposed to simultaneously capture CO_2 and SO_2, and remove sulfite by solid (K_2SO_4) precipitation method. The thermodynamic model of the NH_3-CO_2-SO_2-K_2SO_4-H_2O system for the combined CO_2 and SO_2 capture process was developed and validated in this work to analyze the heat of CO_2 and SO_2 absorption in the NH_3-CO_2-SO_2-H_2O system, and the K_2SO_4 precipitation characteristics in the NH_3-CO_2-SO_2-K_2SO_4-H_2O system. The average heat of CO_2 absorption in the NH_3-CO_2-H_2O system at 40 °C is around −73 kJ/mol CO_2 in 2.5 wt% NH_3 with CO_2 loading between 0.2 and 0.5 C/N. The average heat of SO_2 absorption in the NH_3-SO_2-H_2O system at 40 °C is around −120 kJ/mol SO_2 in 2.5 wt% NH_3 with SO_2 loading between 0 and 0.5 S/N. The average heat of CO_2 absorption in the NH_3-CO_2-SO_2-H_2O system at 40 °C is 77, 68, and 58 kJ/mol CO_2 in 2.5 wt% NH_3 with CO_2 loading between 0.2 and 0.5 C/N, when SO_2 loading is 0, 0.1, 0.2 S/N, respectively. The solubility of K_2SO_4 increases with temperature, CO_2 and SO_2 loadings, but decreases with NH_3 concentration in the CO_2 and SO_2 loaded aqueous NH_3. The thermodynamic evaluation indicates that the combined CO_2 and SO_2 capture process could employ the typical absorption/regeneration process to simultaneously capture CO_2 and SO_2 in an absorber, thermally desorb CO_2 in a stripper, and feasibly remove sulfite (oxidized to sulfate) content by precipitating K_2SO_4 from the lean NH_3 solvent after the lean/rich heat exchanger.

  20. A global catalogue of large SO2 sources and emissions derived from the Ozone Monitoring Instrument

    Directory of Open Access Journals (Sweden)

    V. E. Fioletov

    2016-09-01

    Full Text Available Sulfur dioxide (SO2 measurements from the Ozone Monitoring Instrument (OMI satellite sensor processed with the new principal component analysis (PCA algorithm were used to detect large point emission sources or clusters of sources. The total of 491 continuously emitting point sources releasing from about 30 kt yr−1 to more than 4000 kt yr−1 of SO2 per year have been identified and grouped by country and by primary source origin: volcanoes (76 sources; power plants (297; smelters (53; and sources related to the oil and gas industry (65. The sources were identified using different methods, including through OMI measurements themselves applied to a new emission detection algorithm, and their evolution during the 2005–2014 period was traced by estimating annual emissions from each source. For volcanic sources, the study focused on continuous degassing, and emissions from explosive eruptions were excluded. Emissions from degassing volcanic sources were measured, many for the first time, and collectively they account for about 30 % of total SO2 emissions estimated from OMI measurements, but that fraction has increased in recent years given that cumulative global emissions from power plants and smelters are declining while emissions from oil and gas industry remained nearly constant. Anthropogenic emissions from the USA declined by 80 % over the 2005–2014 period as did emissions from western and central Europe, whereas emissions from India nearly doubled, and emissions from other large SO2-emitting regions (South Africa, Russia, Mexico, and the Middle East remained fairly constant. In total, OMI-based estimates account for about a half of total reported anthropogenic SO2 emissions; the remaining half is likely related to sources emitting less than 30 kt yr−1 and not detected by OMI.

  1. Observation of SO2 degassing at Stromboli volcano using a hyperspectral thermal infrared imager

    Science.gov (United States)

    Smekens, Jean-François; Gouhier, Mathieu

    2018-05-01

    Thermal infrared (TIR) imaging is a common tool for the monitoring of volcanic activity. Broadband cameras with increasing sampling frequency give great insight into the physical processes taking place during effusive and explosive event, while Fourier transform infrared (FTIR) methods provide high resolution spectral information used to assess the composition of volcanic gases but are often limited to a single point of interest. Continuing developments in detector technology have given rise to a new class of hyperspectral imagers combining the advantages of both approaches. In this work, we present the results of our observations of volcanic activity at Stromboli volcano with a ground-based imager, the Telops Hyper-Cam LW, when used to detect emissions of sulfur dioxide (SO2) produced at the vent, with data acquired at Stromboli volcano (Italy) in early October of 2015. We have developed an innovative technique based on a curve-fitting algorithm to quickly extract spectral information from high-resolution datasets, allowing fast and reliable identification of SO2. We show in particular that weak SO2 emissions, such as inter-eruptive gas puffing, can be easily detected using this technology, even with poor weather conditions during acquisition (e.g., high relative humidity, presence of fog and/or ash). Then, artificially reducing the spectral resolution of the instrument, we recreated a variety of commonly used multispectral configurations to examine the efficiency of four qualitative SO2 indicators based on simple Brightness Temperature Difference (BTD). Our results show that quickly changing conditions at the vent - including but not limited to the presence of summit fog - render the establishment of meaningful thresholds for BTD indicators difficult. Building on those results, we propose recommendations on the use of multispectral imaging for SO2 monitoring and routine measurements from ground-based instruments.

  2. A Global Catalogue of Large SO2 Sources and Emissions Derived from the Ozone Monitoring Instrument

    Science.gov (United States)

    Fioletov, Vitali E.; McLinden, Chris A.; Krotkov, Nickolay; Li, Can; Joiner, Joanna; Theys, Nicolas; Carn, Simon; Moran, Mike D.

    2016-01-01

    Sulfur dioxide (SO2) measurements from the Ozone Monitoring Instrument (OMI) satellite sensor processed with the new principal component analysis (PCA) algorithm were used to detect large point emission sources or clusters of sources. The total of 491 continuously emitting point sources releasing from about 30 kt yr(exp -1) to more than 4000 kt yr(exp -1) of SO2 per year have been identified and grouped by country and by primary source origin: volcanoes (76 sources); power plants (297); smelters (53); and sources related to the oil and gas industry (65). The sources were identified using different methods, including through OMI measurements themselves applied to a new emission detection algorithm, and their evolution during the 2005- 2014 period was traced by estimating annual emissions from each source. For volcanic sources, the study focused on continuous degassing, and emissions from explosive eruptions were excluded. Emissions from degassing volcanic sources were measured, many for the first time, and collectively they account for about 30% of total SO2 emissions estimated from OMI measurements, but that fraction has increased in recent years given that cumulative global emissions from power plants and smelters are declining while emissions from oil and gas industry remained nearly constant. Anthropogenic emissions from the USA declined by 80% over the 2005-2014 period as did emissions from western and central Europe, whereas emissions from India nearly doubled, and emissions from other large SO2-emitting regions (South Africa, Russia, Mexico, and the Middle East) remained fairly constant. In total, OMI-based estimates account for about a half of total reported anthropogenic SO2 emissions; the remaining half is likely related to sources emitting less than 30 kt yr(exp -1) and not detected by OMI.

  3. Stakeholders involvement in the decommissioning processes in Italy

    International Nuclear Information System (INIS)

    Dionisi, Mario

    2006-01-01

    The aim of this paper is to present the situation about stakeholders involvement in Italy in the framework of the decommissioning process of the Italian nuclear installations, and in particular the specific experience of the Italian Regulatory Body APAT. Specific aspects and APAT initiatives for building confidence of stakeholders in the process of the release of solid material from the regulatory control are presented. Content: Decommissioning activities in Italy, Decommissioning licensing procedures (Site and material release, APAT - ARPA Partnership approach in the clearance process)

  4. Experimental study on removals of SO2 and NOX using adsorption of activated carbon/microwave desorption.

    Science.gov (United States)

    Ma, Shuang-Chen; Yao, Juan-Juan; Gao, Li; Ma, Xiao-Ying; Zhao, Yi

    2012-09-01

    Experimental studies on desulfurization and denitrification were carried out using activated carbon irradiated by microwave. The influences of the concentrations of nitric oxide (NO) and sulfur dioxide (SO 2 ), the flue gas coexisting compositions, on adsorption properties of activated carbon and efficiencies of desulfurization and denitrification were investigated. The results show that adsorption capacity and removal efficiency of NO decrease with the increasing of SO 2 concentrations in flue gas; adsorption capacity of NO increases slightly first and drops to 12.79 mg/g, and desulfurization efficiency descends with the increasing SO 2 concentrations. Adsorption capacity of SO 2 declines with the increasing of O 2 content in flue gas, but adsorption capacity of NO increases, and removal efficiencies of NO and SO 2 could be larger than 99%. Adsorption capacity of NO declines with the increase of moisture in the flue gas, but adsorption capacity of SO 2 increases and removal efficiencies of NO and SO 2 would be relatively stable. Adsorption capacities of both NO and SO 2 decrease with the increasing of CO 2 content; efficiencies of desulfurization and denitrification augment at the beginning stage, then start to fall when CO 2 content exceeds 12.4%. The mechanisms of this process are also discussed. [Box: see text].

  5. Acidic gases (CO_2, NO_2 and SO_2) capture and dissociation on metal decorated phosphorene

    International Nuclear Information System (INIS)

    Kuang, Anlong; Kuang, Minquan; Yuan, Hongkuan; Wang, Guangzhao; Chen, Hong; Yang, Xiaolan

    2017-01-01

    Highlights: • The light metal decorated phosphorene sheets are very effective for capture of CO_2, NO_2 and SO_2 because of large adsorption energies. • The adsorption energy is obviously dependent on the amount of electrons transferred between acidic gases and metal decorated phosphorene. • Pt-decorated phosphorene can effectively catalyze the dissociation of acidic gas. - Abstract: Density functional theory is employed to investigate the adsorption and dissociation of several acidic gases (CO_2, NO_2 and SO_2) on metal (Li, Al, Ni and Pt) decorated phosphorene. The results show that light metal (Li, Al) decorated phosphorene exhibits a strong adsorption of acidic gases, i.e., the adsorption energy of CO_2 on Li decorated phosphorene is 0.376 eV which is the largest in all adsorption of CO_2 on metal decorated phosphorene and Al decorated phosphorene is most effective for capture of NO_2 and SO_2 due to large adsorption energies of 3.951 and 3.608 eV, respectively. Moreover, Li and Al light metals have stronger economic effectiveness and more friendly environment compared with the transition metals, the strong adsorption ability of acidic gases and low price suggest that Li, Al decorated phosphorene may be useful and promising for collection and filtration of exhaust gases. The reaction energy barriers of acidic gases dissociated process on Pt decorated phosphorene are relatively low and the reaction processes are significantly exothermic, indicating that the dissociation process is favorable.

  6. Experimental study on removals of SO2 and NO(x) using adsorption of activated carbon/microwave desorption.

    Science.gov (United States)

    Ma, Shuang-Chen; Yao, Juan-Juan; Gao, Li; Ma, Xiao-Ying; Zhao, Yi

    2012-09-01

    Experimental studies on desulfurization and denitrification were carried out using activated carbon irradiated by microwave. The influences of the concentrations of nitric oxide (NO) and sulfur dioxide (SO2), the flue gas coexisting compositions, on adsorption properties of activated carbon and efficiencies of desulfurization and denitrification were investigated. The results show that adsorption capacity and removal efficiency of NO decrease with the increasing of SO2 concentrations in flue gas; adsorption capacity of NO increases slightly first and drops to 12.79 mg/g, and desulfurization efficiency descends with the increasing SO2 concentrations. Adsorption capacity of SO2 declines with the increasing of O2 content in flue gas, but adsorption capacity of NO increases, and removal efficiencies of NO and SO2 could be larger than 99%. Adsorption capacity of NO declines with the increase of moisture in the flue gas, but adsorption capacity of SO2 increases and removal efficiencies of NO and SO2 would be relatively stable. Adsorption capacities of both NO and SO2 decrease with the increasing of CO2 content; efficiencies of desulfurization and denitrification augment at the beginning stage, then start to fall when CO2 content exceeds 12.4%. The mechanisms of this process are also discussed. The prominent SO2 and NOx treatment techniques in power plants are wet flue gas desulfurization (FGD) and the catalytic decomposition method like selective catalytic reduction (SCR) or nonselective catalytic reduction (NSCR). However, these processes would have some difficulties in commercial application due to their high investment, requirement of expensive catalysts and large-scale equipment, and so on. A simple SO2 and NOx reduction utilizing decomposition by microwave energy method can be used. The pollutants control of flue gas in the power plants by the method of microwave-induced decomposition using adsorption of activated carbon/microwave desorption can meet the

  7. Progress on the mechanistic understanding of SO2 oxidation catalysts

    DEFF Research Database (Denmark)

    Lapina, Olga B.; Bal'zhinimaev, B.S.; Boghosian, Soghomon

    1999-01-01

    Production, Goskhimizdat (in Russian), Moscow, 1954, p. 348]. In recent years these catalysts have also been used to clean flue gases and other SO; containing, industrial off-gases. In spite of the importance and long utilization of these industrial processes, the catalytic active species and the reaction......For almost a century vanadium oxide based catalysts have been the dominant materials in industrial processes for sulfuric acid production. A vast body of information leading to fundamental knowledge on the catalytic process was obtained by Academician [G.K. Boreskov, Catalysis in Sulphuric Acid...... mechanism. A multiinstrumental investigation that combine the efforts of four groups from four different countries has been carried out on the model system as well as on working industrial catalysts. Detailed information has been obtained on the complex and on the redox chemistry of vanadium. Based on this...

  8. Rate constant for the reaction SO + BrO yields SO2 + Br

    Science.gov (United States)

    Brunning, J.; Stief, L.

    1986-01-01

    The rate of the radical-radical reaction SO + BrO yields SO2 + Br has been determined at 298 K in a discharge flow system near 1 torr pressure with detection of SO and BrO via collision-free sampling mass spectrometry. The rate constant was determined using two different methods: measuring the decay of SO radicals in the presence of an excess of BrO and measuring the decay of BrO radicals in excess SO. The results from the two methods are in reasonable agreement and the simple mean of the two values gives the recommended rate constant at 298 K, k = (5.7 + or - 2.0) x 10 to the -11th cu cm/s. This represents the first determination of this rate constant and it is consistent with a previously derived lower limit based on SO2 formation. Comparison is made with other radical-radical reactions involving SO or BrO. The reaction SO + BrO yields SO2 + Br is of interest for models of the upper atmosphere of the earth and provides a potential coupling between atmospheric sulfur and bromine chemistry.

  9. Measuring the complex behavior of the SO2 oxidation reaction

    Directory of Open Access Journals (Sweden)

    Muhammad Shahzad

    2015-09-01

    Full Text Available The two step reversible chemical reaction involving five chemical species is investigated. The quasi equilibrium manifold (QEM and spectral quasi equilibrium manifold (SQEM are used for initial approximation to simplify the mechanisms, which we want to utilize in order to investigate the behavior of the desired species. They show a meaningful picture, but for maximum clarity, the investigation method of invariant grid (MIG is employed. These methods simplify the complex chemical kinetics and deduce low dimensional manifold (LDM from the high dimensional mechanism. The coverage of the species near equilibrium point is investigated and then we shall discuss moving along the equilibrium of ODEs. The steady state behavior is observed and the Lyapunov function is utilized to study the stability of ODEs. Graphical results are used to describe the physical aspects of measurements.

  10. SO2 influence on the K/La2O3 soot combustion catalyst deactivation

    International Nuclear Information System (INIS)

    Peralta, M.A.; Ulla, M.A.; Querini, C.A.

    2008-01-01

    In the present work, K/La 2 O 3 was prepared and tested as a potential catalyst to be used in a diesel engine exhaust. The soot combustion activity was evaluated by temperature-programmed-oxidation (TPO), and the NO x -catalyst interaction was studied using a microbalance experiment. The SO 2 poisoning process and the regeneration of a poisoned K/La 2 O 3 catalyst were analyzed. The fresh catalyst presented a good soot combustion activity. After being treated with a 1000 ppm SO 2 stream, the catalyst was poisoned due to lanthanum sulfate and potassium sulfate formation. The NO x treatment contributed to the K 2 (SO 4 ) decomposition at the expense of extra La 2 (SO 4 ) 3 formation and the H 2 treatment contributed to the La 2 (SO 4 ) 3 decomposition. (author)

  11. East Asian SO2 pollution plume over Europe – Part 2: Evolution and potential impact

    Directory of Open Access Journals (Sweden)

    A. Stohl

    2009-07-01

    Full Text Available We report on the first observation-based case study of an aged East Asian anthropogenic SO2 pollution plume over Europe. Our airborne measurements in that plume detected highly elevated SO2 mole fractions (up to 900 pmol/mol between about 5000 and 7000 m altitude. Here, we focus on investigations of the origin, dispersion, evolution, conversion, and potential impact of the observed excess SO2. In particular, we investigate SO2 conversion to gas-phase sulfuric acid and sulfuric acid aerosols. Our FLEXPART and LAGRANTO model simulations, along with additional trace gas measurements, suggest that the plume originated from East Asian fossil fuel combustion sources and, 8–7 days prior to its arrival over Europe, ascended over the coast region of central East Asia to 9000 m altitude, probably in a cyclonic system with an associated warm conveyor belt. During this initial plume ascent a substantial fraction of the initially available SO2 must have escaped from removal by cloud processes. Hereafter, while mostly descending slowly, the plume experienced advection across the North Pacific, North America and the North Atlantic. During its upper troposphere travel, clouds were absent in and above the plume and OH-induced gas-phase conversion of SO2 to gas-phase sulfuric acid (GSA was operative, followed by GSA nucleation and condensation leading to sulfuric acid aerosol formation and growth. Our AEROFOR model simulations indicate that numerous large sulfuric acid aerosol particles were formed, which at least tempora-rily, caused substantial horizontal visibility degradation, and which have the potential to act as water vapor condensation nuclei in liquid water cloud formation, already at water vapor supersaturations as low as about 0.1%. Our AEROFOR model simulations also indicate that those fossil fuel combustion generated soot particles, which have survived cloud induced removal during the initial plume ascent, have experienced extensive H2SO4/H2O

  12. 40 CFR 96.286 - Withdrawal from CAIR SO2 Trading Program.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 20 2010-07-01 2010-07-01 false Withdrawal from CAIR SO2 Trading... PROGRAMS (CONTINUED) NOX BUDGET TRADING PROGRAM AND CAIR NOX AND SO2 TRADING PROGRAMS FOR STATE IMPLEMENTATION PLANS CAIR SO2 Opt-in Units § 96.286 Withdrawal from CAIR SO2 Trading Program. Except as provided...

  13. 40 CFR 97.286 - Withdrawal from CAIR SO2 Trading Program.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 20 2010-07-01 2010-07-01 false Withdrawal from CAIR SO2 Trading... PROGRAMS (CONTINUED) FEDERAL NOX BUDGET TRADING PROGRAM AND CAIR NOX AND SO2 TRADING PROGRAMS CAIR SO2 Opt-in Units § 97.286 Withdrawal from CAIR SO2 Trading Program. Except as provided under paragraph (g) of...

  14. 40 CFR 96.253 - Recordation of CAIR SO2 allowances.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 20 2010-07-01 2010-07-01 false Recordation of CAIR SO2 allowances. 96... (CONTINUED) NOX BUDGET TRADING PROGRAM AND CAIR NOX AND SO2 TRADING PROGRAMS FOR STATE IMPLEMENTATION PLANS CAIR SO2 Allowance Tracking System § 96.253 Recordation of CAIR SO2 allowances. (a)(1) After a...

  15. Responses of plants to sulfur containing air pollutants (H2S and SO2)

    NARCIS (Netherlands)

    Maas, Franciscus Marie

    1987-01-01

    Effects of air pollution by hydrogen sulfide (H2S) and sulfur dioxide (SO2) were already reported more than half a century ago. The wider range of pollution by SO2 is reflected in the number of publications concerning effects of SO2 on plants. The major part of the reported studies effects of SO2

  16. 40 CFR 97.253 - Recordation of CAIR SO2 allowances.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 20 2010-07-01 2010-07-01 false Recordation of CAIR SO2 allowances. 97... (CONTINUED) FEDERAL NOX BUDGET TRADING PROGRAM AND CAIR NOX AND SO2 TRADING PROGRAMS CAIR SO2 Allowance Tracking System § 97.253 Recordation of CAIR SO2 allowances. (a)(1) After a compliance account is...

  17. EARLY READING ASSESSMENT INSTRUMENTS: ABILITIES AND PROCESSES INVOLVED

    Directory of Open Access Journals (Sweden)

    Ana Cláudia de Souza

    2017-04-01

    Full Text Available This study investigates the following early reading assessment instruments: “Bateria de Recepção e Produção da Linguagem Verbal” (SCLIAR-CABRAL, 2003a and “Teste de Competência de Leitura de Palavras e Pseudopalavras” (SEABRA; CAPOVILLA, 2010. The main research goal is to analyze in each one of these reading assessment instruments some of the multiple cognitive processes and basic low-level abilities involved in reading. In this sense, decoding, word recognition, lexical access, syntactic and textual processing, and comprehension are the cognitive processes taken into account. With regard to the basic reading abilities, accuracy and fluency (rhythm, prosody and speed are considered. The results indicate that each one of the analyzed reading assessment instruments assesses different aspects of the reading processes and abilities, mainly through off-line measures. ScliarCabral’s assessment battery allows the researcher or the teacher to evaluate the following processes: perception of the grapheme opposition in minimal pairs of words and in sentences, difficulties in sentence processing, skills in decoding the graphemic-phonemic relationship, and textual comprehension. In its turn, the reading assessment instrument proposed by Seabra e Capovilla allows one to evaluate student’s reading development level, by classifying the kind of processing as logographic, alphabetic or orthographic.

  18. Effects of sulphur dioxide (SO2) on growth and flowering of SO2-tolerant and non-tolerant genotypes of Phleum pratense.

    Science.gov (United States)

    Clapperton, M J; Reid, D M

    1994-01-01

    The objective of this study was to compare the growth and interaction of clipping and sulphur dioxide (SO(2)) exposure on SO(2)-tolerant and non-tolerant genotypes of Phleum pratense at two field sites along an SO(2)-concentration gradient. Sulphur-dioxide-tolerant and non-tolerant genotypes of Phleum pratense were identified from indigenous populations that had been collected along the same SO(2)-concentration gradient in southern Alberta, Canada. Physiological differences between the two genotypes were confirmed by supplying leaves with (14)CO(2) and examining the assimilate partitioning between the genotypes. For the field experiment, clones of each genotype and seedlings grown from commercial seed were planted at two different field sites along an SO(2)-emission gradient. There were no differences in growth between the genotypes at the two field sites after the first year except that the SO(2)-tolerant clones had a greater percentage of root length colonised by vesicular-arbuscular (VA) mycorrhizal fungi. After the second growing season, there was a significant decrease in the number of inflorescences produced by plants exposed to SO(2), particularly by the non-tolerant genotype. The added stress of defoliation appeared to increase the sensitivity of flowering to SO(2), again particularly in the non-tolerant genotype. The results of the field study showed that flowering as opposed to vegetative plant growth was more sensitive to long-term low-concentration SO(2) exposure and that this sensitivity was compounded by the stress interaction of defoliation.

  19. Model study of initial adsorption of SO2 on calcite and dolomite

    International Nuclear Information System (INIS)

    Malaga-Starzec, Katarina; Panas, Itai; Lindqvist, Oliver

    2004-01-01

    The rate of calcareous stone degradation is to a significant extent controlled by their surface chemistry with SO 2 . Initial surface sulphite is converted to a harmful gypsum upon, e.g. NO 2 catalysed oxidation. However, it has been observed by scanning electron microscopy that the lateral distributions of gypsum crystals differ between calcitic and dolomitic marbles. The first-principles density functional theory is employed to understand the origin of these fundamentally different morphologies. Here, the stability differences of surface sulphite at calcite CaCO 3 (s) and dolomite Ca x Mg 1-x CO 3 (s) are determined. A qualitative difference in surface sulphite stability, favouring the former, is reported. This is taken to imply that calcitic micro-crystals embedded in a dolomitic matrix act as sinks in the surface sulphation process, controlled by SO 2 diffusion. The subsequent formation of gypsum under such conditions will not require SO 4 2- (aq) ion transport. This explains the homogeneous distribution of gypsum observed on the calcitic micro-crystals in dolomite. In contrast, sulphation on purely calcitic marbles never reaches such high SO 2 coverage. Rather, upon oxidation, SO 4 2- (aq) transport to nucleation centres, such as grain boundaries, is required for the growth of gypsum crystals

  20. Numerical Study of the Simultaneous Oxidation of NO and SO2 by Ozone

    Science.gov (United States)

    Li, Bo; Zhao, Jinyang; Lu, Junfu

    2015-01-01

    This study used two kinetic mechanisms to evaluate the oxidation processes of NO and SO2 by ozone. The performance of the two models was assessed by comparisons with experimental results from previous studies. The first kinetic mechanism was a combined model developed by the author that consisted of 50 species and 172 reactions. The second mechanism consisted of 23 species and 63 reactions. Simulation results of both of the two models show under predictions compared with experimental data. The results showed that the optimized reaction temperature for NO with O3 ranged from 100~200 °C. At higher temperatures, O3 decomposed to O2 and O, which resulted in a decrease of the NO conversion rate. When the mole ratio of O3/NO was greater than 1, products with a higher oxidation state (such as NO3, N2O5) were formed. The reactions between O3 and SO2 were weak; as such, it was difficult for O3 to oxidize SO2. PMID:25642689

  1. Decision-making for complying with SO2 provisions of the Clean Air Act

    International Nuclear Information System (INIS)

    Metzler, A.R.; Gallardy, P.B.; Sebesta, J.J.; Mc Laughlin, B.R.; Ireland, P.A.

    1992-01-01

    Prior to the Clean Air Act of 1990 (CAA), SO 2 removal options were based on a command and control approach for each plant. This approach usually resulted in the addition of an FGD system. However, the CAA offers a market based emission allowance program which offers considerable flexibility for compliance with the new regulations. The flexibility for compliance introduces more available options into the evaluation and increases the complexity of the decision-making process. This paper discusses the methodology of a recent analysis which evaluated various strategies for meeting SO 2 compliance. The importance of evaluating options based on certain goals is discussed. An overall goal was established to develop a flexible and least cost compliance plan. However, these goals need to be balanced against constraints for the utility which may include: minimizing SO 2 allowance market risk; optimizing the availability, cost and timing of capital expenditures into the analysis; minimizing site impacts and construction lead time; and coordinating strategies from various units and stations into a cohesive plan

  2. Corrosion of Pipeline and Wellbore Steel by Liquid CO2 Containing Trace Amounts of Water and SO2

    Science.gov (United States)

    McGrail, P.; Schaef, H. T.; Owen, A. T.

    2009-12-01

    Carbon dioxide capture and storage in deep saline formations is currently considered the most attractive option to reduce greenhouse gas emissions with continued use of fossil fuels for energy production. Transporting captured CO2 and injection into suitable formations for storage will necessarily involve pipeline systems and wellbores constructed of carbon steels. Industry standards currently require nearly complete dehydration of liquid CO2 to reduce corrosion in the pipeline transport system. However, it may be possible to establish a corrosion threshold based on H2O content in the CO2 that could allow for minor amounts of H2O to remain in the liquid CO2 and thereby eliminate a costly dehydration step. Similarly, trace amounts of sulfur and nitrogen compounds common in flue gas streams are currently removed through expensive desulfurization and catalytic reduction processes. Provided these contaminants could be safely and permanently transported and stored in the geologic reservoir, retrofits of existing fossil-fuel plants could address comprehensive emissions reductions, including CO2 at perhaps nearly the same capital and operating cost. Because CO2-SO2 mixtures have never been commercially transported or injected, both experimental and theoretical work is needed to understand corrosion mechanisms of various steels in these gas mixtures containing varying amounts of water. Experiments were conducted with common tool steel (AISI-01) and pipeline steel (X65) immersed in liquid CO2 at room temperature containing ~1% SO2 and varying amounts of H2O (0 to 2500 ppmw). A threshold concentration of H2O in the liquid CO2-SO2 mixture was established based on the absence of visible surface corrosion. For example, experiments exposing steel to liquid CO2-SO2 containing ~300 ppmw H2O showed a delay in onset of visible corrosion products and minimal surface corrosion was visible after five days of testing. However increasing the water content to 760 ppmw produced extensive

  3. Public involvement in decision making process in nuclear field

    International Nuclear Information System (INIS)

    Constantin, M.; Diaconu, D.

    2009-01-01

    Decision Making Process (DMP) in nuclear field is influenced by multiple factors such as: complex technical aspects, diversity of stakeholders, long term risks, psychological stresses, societal attitudes, etc. General public is sometimes considered as the only one of stakeholders, the involvement of the public being seen as a factor to obtain the acceptance in the late phase of DMP. Generally it is assessed by public consultation on the environment impact studies and by approval of the sitting through the local authorities decision. Modern society uses methods to involve public from the beginning of DMP. The paper shows a general view of the methods and tools used in Europe for public involvement in DMP. The process of construction of a continuous democratic dialog inside of Romanian Stakeholder Group (RSG) in the frame of the FP6-COWAM2 and CIP projects is presented with a focusing of the barriers and factors of disturbing the trust and collaboration between stakeholders. The influence on the public acceptance is also discussed. (authors)

  4. Oxidation of SO2 and formation of water droplets under irradiation of 20MeV protons in N2/H2O/SO2

    DEFF Research Database (Denmark)

    Tomita, Shigeo; Nakai, Yoichi; Funada, Shuhei

    2015-01-01

    We have performed an experiment on charged droplet formation in a humidified N2 gas with trace SO2 concentration and induced by 20MeV proton irradiation. It is thought that SO2 reacts with the chemical species, such as OH radicals, generated through the reactions triggered by N2+ production. Both...

  5. Volcanic Ash and SO2 Monitoring Using Suomi NPP Direct Broadcast OMPS Data

    Science.gov (United States)

    Seftor, C. J.; Krotkov, N. A.; McPeters, R. D.; Li, J. Y.; Brentzel, K. W.; Habib, S.; Hassinen, S.; Heinrichs, T. A.; Schneider, D. J.

    2014-12-01

    NASA's Suomi NPP Ozone Science Team, in conjunction with Goddard Space Flight Center's (GSFC's) Direct Readout Laboratory, developed the capability of processing, in real-time, direct readout (DR) data from the Ozone Mapping and Profiler Suite (OMPS) to perform SO2 and Aerosol Index (AI) retrievals. The ability to retrieve this information from real-time processing of DR data was originally developed for the Ozone Monitoring Instrument (OMI) onboard the Aura spacecraft and is used by Volcano Observatories and Volcanic Ash Advisory Centers (VAACs) charged with mapping ash clouds from volcanic eruptions and providing predictions/forecasts about where the ash will go. The resulting real-time SO2 and AI products help to mitigate the effects of eruptions such as the ones from Eyjafjallajokull in Iceland and Puyehue-Cordón Caulle in Chile, which cause massive disruptions to airline flight routes for weeks as airlines struggle to avoid ash clouds that could cause engine failure, deeply pitted windshields impossible to see through, and other catastrophic events. We will discuss the implementation of real-time processing of OMPS DR data by both the Geographic Information Network of Alaska (GINA) and the Finnish Meteorological Institute (FMI), which provide real-time coverage over some of the most congested airspace and over many of the most active volcanoes in the world, and show examples of OMPS DR processing results from recent volcanic eruptions.

  6. Emission sensitization processes involving Nd{sup 3+} in YAG

    Energy Technology Data Exchange (ETDEWEB)

    Lupei, V., E-mail: lupei_voicu@yahoo.com [National Institute of Laser, Plasma and Radiation Physics, Bucharest 077125 (Romania); Lupei, A.; Gheorghe, C. [National Institute of Laser, Plasma and Radiation Physics, Bucharest 077125 (Romania); Ikesue, A. [World Lab. Co., Nagoya (Japan)

    2016-02-15

    The paper investigates the characteristics of sensitization processes of Nd{sup 3+} emission in YAG ceramics under broad band pumping by co-doping with Cr{sup 3+} and the prospect of using Nd{sup 3+} and Cr{sup 3+} for sensitization of emission of Yb{sup 3+}. It is evidenced that the energy transfer from Cr{sup 3+} to Nd{sup 3+} involves both direct and weak migration-assisted processes and is thus dependent on the concentrations of both species. It is also found that the ion–ion interaction responsible for the direct transfer contains besides the dipole–dipole coupling strong superexchange contribution that dominates the transfer to the Nd{sup 3+} ions up to the third coordination sphere and has major implication in sensitization. Investigation of (Cr, Nd, Yb)-doped YAG ceramics shows that Cr{sup 3+} can sensitize the emission of Yb{sup 3+} both via the chain Cr–Nd–Yb or by direct Cr–Yb energy transfer. The prospect of utilization of these processes in the solar-pumped laser is discussed. - Highlights: • The efficiency of sensitization increases at high Cr and Nd doping concentrations. • The Cr-to-Nd energy transfer involves both direct and migration-assisted processes. • The direct transfer implies both dipole–dipole and superexchange interactions. • The superexchange interaction has major influence on sensitization. • Sensitized emission of Yb{sup 3+} in (Cr,Nd,Yb):YAG by Cr–Nd–Yb and Cr–Yb transfers.

  7. Smog chamber studies on the air chemistry of biogenic hydrocarbons in the presence of ozone, NOx and SO2

    International Nuclear Information System (INIS)

    Nolting, F.; Zetzsch, C.

    1990-01-01

    The influence of SO 2 on the photochemical degradation processes of the biogenic hydrocarbon α-pinene was studied with respect to the present forest decline. For that purpose premixed air was irradiated with simulated sunlight in laboratory experiments using a modified smog chamber. The performance of a novel semi continuous analyzer for H 2 SO 4 /sulfate was tested for smog chamber studies of the transformation of SO 2 to sulfuric acid and sulfur containing aerosol. An influence of SO 2 on the formation of ozone was not detected. The rates of degradation cannot be described by gas phase reactions alone, and, in addition, they are faster in the presence of humidity. Depending on humidity, 30-50% of the consumed SO 2 can be recovered in the suspended aerosol. In the presence of 60% relative humidity the nearly exclusive product is sulfur aerosol that needs further characterization. (orig.) With 9 figs., 42 refs [de

  8. Sulphur dioxide (SO2) electrotransfer in electric field generated by corona discharge

    International Nuclear Information System (INIS)

    Wang, Zu-wu; Guo, Jia; Zeng, Han-cai; Ge, Chun-liang; Yu, Jiang

    2007-01-01

    The mechanism of the forming SO 2 negative ions and their electrotransfer in the corona discharge electric field was investigated in this paper. The experimental results showed that SO 2 electrotransfer occurred in the electric field with corona discharge, which had potential applications in removal of SO 2 of the flue gas from coal-fired power plants by electrotransfer. SO 2 electrotransfer was enhanced by higher electric-field intensity or a larger discharging area. Assistant uniform electric field after the corona discharge electric field would improve SO 2 electrotransfer. The increment of the desulphurization efficiency by SO 2 electrotransfer might reach as high as 50%. (author)

  9. Understanding the cognitive processes involved in writing to learn.

    Science.gov (United States)

    Arnold, Kathleen M; Umanath, Sharda; Thio, Kara; Reilly, Walter B; McDaniel, Mark A; Marsh, Elizabeth J

    2017-06-01

    Writing is often used as a tool for learning. However, empirical support for the benefits of writing-to-learn is mixed, likely because the literature conflates diverse activities (e.g., summaries, term papers) under the single umbrella of writing-to-learn. Following recent trends in the writing-to-learn literature, the authors focus on the underlying cognitive processes. They draw on the largely independent writing-to-learn and cognitive psychology learning literatures to identify important cognitive processes. The current experiment examines learning from 3 writing tasks (and 1 nonwriting control), with an emphasis on whether or not the tasks engaged retrieval. Tasks that engaged retrieval (essay writing and free recall) led to better final test performance than those that did not (note taking and highlighting). Individual differences in structure building (the ability to construct mental representations of narratives; Gernsbacher, Varner, & Faust, 1990) modified this effect; skilled structure builders benefited more from essay writing and free recall than did less skilled structure builders. Further, more essay-like responses led to better performance, implicating the importance of additional cognitive processes such as reorganization and elaboration. The results highlight how both task instructions and individual differences affect the cognitive processes involved when writing-to-learn, with consequences for the effectiveness of the learning strategy. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

  10. SO2 and NO removal from flue gas over V2O5/AC at lower temperatures - role of V2O5 on SO2 removal

    International Nuclear Information System (INIS)

    Ma, Jianrong; Liu, Zhenyu; Liu, Qingya; Guo, Shijie; Huang, Zhanggen; Xiao, Yong

    2008-01-01

    Supporting V 2 O 5 onto an activated coke (AC) has been reported to significantly increase the AC's activity in simultaneous SO 2 and NO removal from flue gas. To understand the role of V 2 O 5 on SO 2 removal, V 2 O 5 /AC is studied through SO 2 removal reaction, surface analysis, X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and Fourier transform infrared (FTIR) techniques. It is found that the main role of V 2 O 5 in SO 2 removal over V 2 O 5 /AC is to catalyze SO 2 oxidation through a VOSO 4 -like intermediate species, which reacts with O 2 to form SO 3 and V 2 O 5 . The SO 3 formed transfers from the V sites to AC sites and then reacts with H 2 O to form H 2 SO 4 . At low V 2 O 5 loadings, a V atom is able to catalyze as many as 8 SO 2 molecules to SO 3 . At high V 2 O 5 loadings, however, the number of SO 2 molecules catalyzed by a V atom is much less, due possibly to excessive amounts of V 2 O 5 sites in comparison to the pores available for SO 3 and H 2 SO 4 storage. (author)

  11. Motor cortical processing is causally involved in object recognition.

    Science.gov (United States)

    Decloe, Rebecca; Obhi, Sukhvinder S

    2013-12-14

    Motor activity during vicarious experience of actions is a widely reported and studied phenomenon, and motor system activity also accompanies observation of graspable objects in the absence of any actions. Such motor activity is thought to reflect simulation of the observed action, or preparation to interact with the object, respectively. Here, in an initial exploratory study, we ask whether motor activity during observation of object directed actions is involved in processes related to recognition of the object after initial exposure. Single pulse Transcranial Magnetic Stimulation (TMS) was applied over the thumb representation of the motor cortex, or over the vertex, during observation of a model thumb typing on a cell-phone, and performance on a phone recognition task at the end of the trial was assessed. Disrupting motor processing over the thumb representation 100 ms after the onset of the typing video impaired the ability to recognize the phone in the recognition test, whereas there was no such effect for TMS applied over the vertex and no TMS trials. Furthermore, this effect only manifested for videos observed from the first person perspective. In an additional control condition, there was no evidence for any effects of TMS to the thumb representation or vertex when observing and recognizing non-action related shape stimuli. Overall, these data provide evidence that motor cortical processing during observation of object-directed actions from a first person perspective is causally linked to the formation of enduring representations of objects-of-action.

  12. Motor cortical processing is causally involved in object recognition

    Science.gov (United States)

    2013-01-01

    Background Motor activity during vicarious experience of actions is a widely reported and studied phenomenon, and motor system activity also accompanies observation of graspable objects in the absence of any actions. Such motor activity is thought to reflect simulation of the observed action, or preparation to interact with the object, respectively. Results Here, in an initial exploratory study, we ask whether motor activity during observation of object directed actions is involved in processes related to recognition of the object after initial exposure. Single pulse Transcranial Magnetic Stimulation (TMS) was applied over the thumb representation of the motor cortex, or over the vertex, during observation of a model thumb typing on a cell-phone, and performance on a phone recognition task at the end of the trial was assessed. Disrupting motor processing over the thumb representation 100 ms after the onset of the typing video impaired the ability to recognize the phone in the recognition test, whereas there was no such effect for TMS applied over the vertex and no TMS trials. Furthermore, this effect only manifested for videos observed from the first person perspective. In an additional control condition, there was no evidence for any effects of TMS to the thumb representation or vertex when observing and recognizing non-action related shape stimuli. Conclusion Overall, these data provide evidence that motor cortical processing during observation of object-directed actions from a first person perspective is causally linked to the formation of enduring representations of objects-of-action. PMID:24330638

  13. Green's functions through so(2,1) lie algebra in nonrelativistic quantum mechanics

    International Nuclear Information System (INIS)

    Boschi-Filho, H.; Vaidya, A.N.

    1991-01-01

    The authors discuss an algebraic technique to construct the Green's function for systems described by the noncompact so(2,1) Lie algebra. They show that this technique solves the one-dimensional linear oscillator and Coulomb potentials and also generates particular solutions for other one-dimensional potentials. Then they construct explicitly the Green's function for the three-dimensional oscillator and the three-dimensional Coulomb potential, which are generalizations of the one-dimensional cases, and the Coulomb plus an Aharanov-Bohm, potential. They discuss the dynamical algebra involved in each case and also find their wave functions and bound state spectra. Finally they introduce in each case and also find their wave functions and bound state spectra. Finally they introduce a point canonical transformation in the generators of so(2,10) Lie algebra, show that this procedure permits us to solve the one-dimensional Morse potential in addition to the previous cases, and construct its Green's function and find its energy spectrum and wave functions

  14. Public involvement in the decision making process, Argentine experience

    International Nuclear Information System (INIS)

    Clein, D.

    1999-01-01

    In the frame of a young participative democracy the Comision Nacional de Energia Atomica (C.N.E.A.), technical and legal responsible for radioactive waste management, is developing a plan for the close out of tailings facilities from past mining and milling operations and the environmental restoration of nine different sites in six provinces all over the country. In the first site, Malargue Facility, different activities have been developed promoting public involvement in the decision making process. The lessons learned and the experience acquired have given the background for the systematization of public consultation in the ongoing and future stages of the plan. Malargue's experience in this field will be analyzed stressing on different aspects considered of importance for the design of a communicational strategy adapted to the characteristics of a society without experience in this field. The influence of public concern on conservative bias of technical decisions will be evaluated. (author)

  15. Photocatalytic removal of SO2 using natural zeolite modified by TiO2 and polyoxypropylene surfactant.

    Science.gov (United States)

    Amini, Nasibeh; Soleimani, Mohsen; Mirghaffari, Nourollah

    2018-01-25

    Air pollution due to emission of various hazardous gases such as SO 2 into the atmosphere and its control is an important environmental issue. Application of photocatalysts is considered as a suitable process to control the gaseous pollutants. In this study, the efficiency of clinoptilolite as a natural zeolite (Ze) modified by TiO 2 (Ze-Ti) and a polymeric surfactant polyoxypropylene (Ze-Ti-POP) for removal of SO 2 was investigated. The nanocomposites were characterized by SEM, EDX, and BET analyses. The photocatalytic oxidation experiments of SO 2 by the nanocomposites and natural zeolite were done under UV irradiation with initial SO 2 concentration of 500 ppm in a photoreactor. The effects of different factors including reaction time, catalyst dose, UV irradiation intensity, humidity content, and calcination temperature and dose of TiO 2 were studied. The modification of clinoptilolite by TiO 2 and POP increased considerably the BET specific surface area of the nanocomposites. The results showed that maximum removal efficiencies of SO 2 by Ze-Ti and Ze-Ti-POP under the optimum experimental conditions were 82.1 and 87.4%, respectively. Adsorption kinetics data well fitted with the Langmuir-Hinshelwood model. Moreover, reusing of nanocomposites after three regeneration cycles indicated that application of Ze-Ti and Ze-Ti-POP nanocomposites could be a promising approach for SO 2 removal. Graphical abstract ᅟ.

  16. 76 FR 79541 - Revisions to Final Response to Petition From New Jersey Regarding SO2

    Science.gov (United States)

    2011-12-22

    ... Revisions to Final Response to Petition From New Jersey Regarding SO2 Emissions From the Portland Generating... Jersey Regarding SO2 Emissions From the Portland Generating Station (Portland) published November 7, 2011... Final Response to Petition From New Jersey Regarding SO2 Emissions From the Portland Generating Station...

  17. 40 CFR 60.4330 - What emission limits must I meet for sulfur dioxide (SO2)?

    Science.gov (United States)

    2010-07-01

    ... sulfur dioxide (SO2)? 60.4330 Section 60.4330 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... sulfur dioxide (SO2)? (a) If your turbine is located in a continental area, you must comply with either... gases which contain SO2 in excess of 110 nanograms per Joule (ng/J) (0.90 pounds per megawatt-hour (lb...

  18. 40 CFR 73.19 - Certain units with declining SO2 rates.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 16 2010-07-01 2010-07-01 false Certain units with declining SO2 rates... declining SO2 rates. (a) Eligibility. A unit is eligible for allowance allocations under this section if it... generator with nameplate capacity equal to or greater than 75 MWe; (3) Its 1985 actual SO2 emissions rate...

  19. Catalytic conversion of CO, NO and SO2 on supported sulfide catalysts. Part 2. Catalytic reduction of NO and SO2 by CO

    International Nuclear Information System (INIS)

    Zhuang, S.-X.; Yamazaki, M.; Omata, K.; Takahashi, Y.; Yamada, M.

    2001-01-01

    To investigate the possibility of simultaneous catalytic reduction of NO and SO 2 by CO, reactions of NO, NO-CO, and NO-SO 2 -CO were performed on γ-alumina-supported sulfides of transition metals including Co, Mo, CoMo and FeMo. NO was decomposed into N 2 O and N 2 accompanied with the formation of SO 2 ; this serious oxidation of lattice sulfur resulted in the deactivation of the catalysts. The addition of CO to the NO stream suppressed SO 2 formation and yielded COS instead. A stoichiometric conversion of NO and CO to N 2 and CO 2 was observed above 350C on the CoMo and the FeMo catalysts. Although the CO addition lengthened catalyst life, it was not enough to maintain activity. After the NO-CO reaction, an XPS analysis showed the growth of Mo 6+ and SO 4 2- peaks, especially for the sulfided FeMo/Al 2 O 3 ; the FeMo catalyst underwent strong oxidation in the NO-CO reaction. The NO and the NO-CO reactions proceeded non-catalytically, consuming catalyst lattice sulfur to yield SO 2 or COS. The addition of SO 2 in the NO-CO system enabled in situ regeneration of the catalysts; the catalysts oxidized through abstraction of lattice sulfur experienced anew reduction and sulfurization through the SO 2 -CO reaction at higher temperature. NO and SO 2 were completely and catalytically converted at 400C on the sulfided CoMo/Al 2 O 3 . By contrast, the sulfided FeMo/Al 2 O 3 was easily oxidized by NO and hardly re-sulfided under the test conditions. Oxidation states of the metals before and after the reactions were determined. Silica and titania-supported CoMo catalysts were also evaluated to study support effects

  20. Sulfur isotope fractionation during heterogeneous oxidation of SO2 on mineral dust

    Directory of Open Access Journals (Sweden)

    P. Hoppe

    2012-06-01

    Full Text Available Mineral dust is a major fraction of global atmospheric aerosol, and the oxidation of SO2 on mineral dust has implications for cloud formation, climate and the sulfur cycle. Stable sulfur isotopes can be used to understand the different oxidation processes occurring on mineral dust. This study presents measurements of the 34S/32S fractionation factor α34 for oxidation of SO2 on mineral dust surfaces and in the aqueous phase in mineral dust leachate. Sahara dust, which accounts for ~60% of global dust emissions and loading, was used for the experiments. The fractionation factor for aqueous oxidation in dust leachate is αleachate = 0.9917±0.0046, which is in agreement with previous measurements of aqueous SO2 oxidation by iron solutions. This fractionation factor is representative of a radical chain reaction oxidation pathway initiated by transition metal ions. Oxidation on the dust surface at subsaturated relative humidity (RH had an overall fractionation factor of αhet = 1.0096±0.0036 and was found to be almost an order of magnitude faster when the dust was simultaneously exposed to ozone, light and RH of ~40%. However, the presence of ozone, light and humidity did not influence isotope fractionation during oxidation on dust surfaces at subsaturated relative humidity. All the investigated reactions showed mass-dependent fractionation of 33S relative to 34S. A positive matrix factorization model was used to investigate surface oxidation on the different components of dust. Ilmenite, rutile and iron oxide were found to be the most reactive components, accounting for 85% of sulfate production with a fractionation factor of α34 = 1.012±0.010. This overlaps within the analytical uncertainty with the fractionation of other major atmospheric oxidation pathways such as the oxidation of SO2 by H2O2 and O3 in the aqueous phase and OH in the gas phase. Clay minerals accounted for roughly 12% of the sulfate production, and oxidation on clay minerals

  1. SO2 columns over China: Temporal and spatial variations using OMI and GOME-2 observations

    Science.gov (United States)

    Huanhuan, Yan; Liangfu, Chen; Lin, Su; Jinhua, Tao; Chao, Yu

    2014-03-01

    Enhancements of SO2 column amounts due to anthropogenic emission sources over China were shown in this paper by using OMI and GOME-2 observations. The temporal and spatial variations of SO2 columns over China were analyzed for the time period 2005-2010. Beijing and Chongqing showed a high concentration in the SO2 columns, attributable to the use of coal for power generation in China and the characteristic of terrain and meteorology. The reduction of SO2 columns over Beijing and surrounding provinces in 2008 was observed by OMI, which confirms the effectiveness of strict controls on pollutant emissions and motor vehicle traffic before and during 2008 Olympic and Paralympic Games. The SO2 columns over China from GOME-2 (0.2-0.5 DU) were lower than those from OMI (0.6-1 DU), but both showed a decrease in SO2 columns over northern China since 2008 (except an increase in OMI SO2 in 2010).

  2. Interaction of SO2 with the Surface of a Water Nanodroplet.

    Science.gov (United States)

    Zhong, Jie; Zhu, Chongqin; Li, Lei; Richmond, Geraldine L; Francisco, Joseph S; Zeng, Xiao Cheng

    2017-11-29

    We present a comprehensive computational study of interaction of a SO 2 with water molecules in the gas phase and with the surface of various sized water nanodroplets to investigate the solvation behavior of SO 2 in different atmospheric environments. Born-Oppenheimer molecular dynamics (BOMD) simulation shows that, in the gas phase and at a temperature of 300 K, the dominant interaction between SO 2 and H 2 O is (SO 2 ) S···O (H 2 O) , consistent with previous density-functional theory (DFT) computation at 0 K. However, at the surface of a water nanodroplet, BOMD simulation shows that the hydrogen-bonding interaction of (SO 2 ) O···H (H 2 O) becomes increasingly important with the increase of droplet size, reflecting a marked effect of the water surface on the SO 2 solvation. This conclusion is in good accordance with spectroscopy evidence obtained previously (J. Am. Chem. Soc. 2005, 127, 16806; J. Am. Chem. Soc. 2006, 128, 3256). The prevailing interaction (SO 2 ) O···H (H 2 O) on a large droplet is mainly due to favorable exposure of H atoms of H 2 O at the air-water interface. Indeed, the conversion of the dominant interaction in the gas phase (SO 2 ) S···O (H 2 O) to the dominant interaction on the water nanodroplet (SO 2 ) O···H (H 2 O) may incur effects on the SO 2 chemistry in atmospheric aerosols because the solvation of SO 2 at the water surface can affect the reactive sites and electrophilicity of SO 2 . Hence, the solvation of SO 2 on the aerosol surface may have new implications when studying SO 2 chemistry in the aerosol-containing troposphere.

  3. Physiological characteristics of Plantago major under SO2 exposure as affected by foliar iron spray.

    Science.gov (United States)

    Mohasseli, Vahid; Khoshgoftarmanesh, Amir Hossein; Shariatmadari, Hossein

    2017-08-01

    Sulfur dioxide (SO 2 ) is considered as a main air pollutant in industrialized areas that can damage vegetation. In the present study, we investigated how exposure to SO 2 and foliar application of iron (Fe) would affect certain physiological characteristics of Plantago major. The plant seedlings exposed or unexposed to SO 2 (3900 μg m -3 ) were non-supplemented or supplemented with Fe (3 g L -1 ) as foliar spray. Plants were exposed to SO 2 for 6 weeks in 100 × 70 × 70 cm chambers. Fumigation of plants with SO 2 was performed for 3 h daily for 3 days per week (alternate day). Lower leaf Fe concentration in the plants exposed to SO 2 at no added Fe treatment was accompanied with incidence of chlorosis symptoms and reduced chlorophyll concentration. No visible chlorotic symptoms were observed on the SO 2 -exposed plants supplied with Fe that accumulated higher Fe in their leaves. Both at with and without added Fe treatments, catalase (CAT) and peroxidase (POD) activity was higher in the plants fumigated with SO 2 in comparison with those non-fumigated with SO 2 . Foliar application of Fe was also effective in increasing activity of antioxidant enzymes CAT and POD. Exposure to SO 2 led to reduced cellulose but enhanced lignin content of plant leaf cell wall. The results obtained showed that foliar application of Fe was effective in reducing the effects of exposure to SO 2 on cell wall composition. In contrast to SO 2 , application of Fe increased cellulose while decreased lignin content of the leaf cell wall. This might be due to reduced oxidative stress induced by SO 2 in plants supplied with Fe compared with those unsupplied with Fe.

  4. Re-Examining Embodied SO2 and CO2 Emissions in China

    Directory of Open Access Journals (Sweden)

    Rui Huang

    2018-05-01

    Full Text Available CO2 and SO2, while having different environmental impacts, are both linked to the burning of fossil fuels. Research on joint patterns of CO2 emissions and SO2 emissions may provide useful information for decision-makers to reduce these emissions effectively. This study analyzes both CO2 emissions and SO2 emissions embodied in interprovincial trade in 2007 and 2010 using multi-regional input–output analysis. Backward and forward linkage analysis shows that Production and Supply of Electric Power and Steam, Non-metal Mineral Products, and Metal Smelting and Pressing are key sectors for mitigating SO2 and CO2 emissions along the national supply chain. The total SO2 emissions and CO2 emissions of these sectors accounted for 81% and 76% of the total national SO2 emissions and CO2 emissions, respectively.

  5. Synergistic reaction between SO2 and NO2 on mineral oxides: a potential formation pathway of sulfate aerosol.

    Science.gov (United States)

    Liu, Chang; Ma, Qingxin; Liu, Yongchun; Ma, Jinzhu; He, Hong

    2012-02-07

    Sulfate is one of the most important aerosols in the atmosphere. A new sulfate formation pathway via synergistic reactions between SO(2) and NO(2) on mineral oxides was proposed. The heterogeneous reactions of SO(2) and NO(2) on CaO, α-Fe(2)O(3), ZnO, MgO, α-Al(2)O(3), TiO(2), and SiO(2) were investigated by in situ Diffuse Reflectance Infrared Fourier Transform Spectroscopy (in situ DRIFTS) at ambient temperature. Formation of sulfate from adsorbed SO(2) was promoted by the coexisting NO(2), while surface N(2)O(4) was observed as the crucial oxidant for the oxidation of surface sulfite. This process was significantly promoted by the presence of O(2). The synergistic effect between SO(2) and NO(2) was not observed on other mineral particles (such as CaCO(3) and CaSO(4)) probably due to the lack of the surface reactive oxygen sites. The synergistic reaction between SO(2) and NO(2) on mineral oxides resulted in the formation of internal mixtures of sulfate, nitrate, and mineral oxides. The change of mixture state will affect the physicochemical properties of atmospheric particles and therefore further influence their environmental and climate effects.

  6. Impact of SO2 and NO on CO Oxidation under Post-Flame Conditions

    DEFF Research Database (Denmark)

    Glarborg, Peter; Kubel, Dorte; Dam-Johansen, Kim

    1996-01-01

    An experimental and theoretical study of the effect of SO2 on moist CO oxidation with and without NO present was carried out under plug-flow conditions. The H/S/O thermochemistry and reaction subset was revised and a chemical kinetic model established that provide a good description of the effect...... of SO2 and NO on CO oxidation as well as the SO2/SO3 ratio in the products....

  7. 40 CFR 60.43Da - Standard for sulfur dioxide (SO2).

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 6 2010-07-01 2010-07-01 false Standard for sulfur dioxide (SO2). 60... for sulfur dioxide (SO2). (a) On and after the date on which the initial performance test is completed...) of this section, any gases that contain SO2 in excess of: (1) 520 ng/J (1.20 lb/MMBtu) heat input and...

  8. 40 CFR 60.43 - Standard for sulfur dioxide (SO2).

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 6 2010-07-01 2010-07-01 false Standard for sulfur dioxide (SO2). 60... sulfur dioxide (SO2). (a) Except as provided under paragraph (d) of this section, on and after the date... affected facility any gases that contain SO2 in excess of: (1) 340 ng/J heat input (0.80 lb/MMBtu) derived...

  9. The Characterization of Cognitive Processes Involved in Chemical Kinetics Using a Blended Processing Framework

    Science.gov (United States)

    Bain, Kinsey; Rodriguez, Jon-Marc G.; Moon, Alena; Towns, Marcy H.

    2018-01-01

    Chemical kinetics is a highly quantitative content area that involves the use of multiple mathematical representations to model processes and is a context that is under-investigated in the literature. This qualitative study explored undergraduate student integration of chemistry and mathematics during problem solving in the context of chemical…

  10. Adsorption of SO2 on bituminous coal char and activated carbon fiber prepared from phenol formaldehyde

    Science.gov (United States)

    DeBarr, Joseph A.; Lizzio, Anthony A.; Daley, Michael A.

    1996-01-01

    Carbon-based materials are used commercially to remove SO2 from coal combustion flue gases. Historically, these materials have consisted of granular activated carbons prepared from lignite or bituminous coal. Recent studies have reported that activated carbon fibers (ACFs) may have potential in this application due to their relatively high SO2 adsorption capacity. In this paper, a comparison of SO2 adsorption for both coal-based carbons and ACFs is presented, as well as ideas on carbon properties that may influence SO2 adsorption

  11. Adsorption of SO2 on bituminous coal char and activated carbon fiber

    Science.gov (United States)

    DeBarr, Joseph A.; Lizzio, Anthony A.; Daley, Michael A.

    1997-01-01

    The SO2 adsorption behaviors of activated carbons produced from Illinois coal and of commercially prepared activated carbon fibers (ACFs) were compared. There was no relation between surface area of coal-based carbons and SO2 adsorption, whereas adsorption of SO2 on the series of ACFs was inversely proportional to N2 BET surface area. Higher surface area ACFs had wider pores and adsorbed less SO2; thus, pore size distribution is thought to play a significant role in SO2 adsorption for these materials. Oxidation with HNO3 and/or H2SO4, followed by heat treatment at 700−925°C to remove carbon−oxygen complexes, resulted in increased SO2 adsorption for both coal chars and ACFs. This behavior was explained by an increase in the available number of free sites, previously occupied by oxygen and now available for SO2 adsorption. The use of nitrogen-containing functional groups on ACFs of proper pore size shows promise for further increasing SO2 adsorption capacities. Knowledge of the relationship among the number of free sites, pore size, and surface chemistry on corresponding SO2 adsorption should lead to the development of more efficient adsorbents prepared from either coal or ACFs.

  12. Mechanisms of Heightened Airway Sensitivity and Responses to Inhaled SO2 in Asthmatics.

    Science.gov (United States)

    Reno, Anita L; Brooks, Edward G; Ameredes, Bill T

    2015-01-01

    Sulfur dioxide (SO2) is a problematic inhalable air pollutant in areas of widespread industrialization, not only in the United States but also in countries undergoing rapid industrialization, such as China, and it can be a potential trigger factor for asthma exacerbations. It is known that asthmatics are sensitive to the effects of SO2; however, the basis of this enhanced sensitivity remains incompletely understood. A PubMed search was performed over the course of 2014, encompassing the following terms: asthma, airway inflammation, sulfur dioxide, IL-10, mouse studies, and human studies. This search indicated that biomarkers of SO2 exposure, SO2 effects on airway epithelial cell function, and animal model data are useful in our understanding of the body's response to SO2, as are SO2-associated amplification of allergic inflammation, and potential promotion of neurogenic inflammation due to chemical irritant properties. While definitive answers are still being sought, these areas comprise important foci of consideration regarding asthmatic responses to inhaled SO2. Furthermore, IL-10 deficiency associated with asthma may be another important factor associated with an inability to resolve inflammation and mitigate oxidative stress resulting from SO2 inhalation, supporting the idea that asthmatics are predisposed to SO2 sensitivity, leading to asthma exacerbations and airway dysfunction.

  13. Drowning unconformities: Palaeoenvironmental significance and involvement of global processes

    Science.gov (United States)

    Godet, Alexis

    2013-07-01

    Drowning unconformities are stratigraphic key surfaces in the history of carbonate platforms. They mostly consist in the deposition of deep marine facies on top of shallow marine limestones. Although large-scale depositional geometries mimic lowstand systems track architecture, these sedimentary turnovers are developed in relation with major sea level rise, inducing an increase in the rate of creation of accommodation space that outpaces the capacity of carbonate to keep up. This so-called paradox of carbonate platform drowning implies that parameters other than purely eustatic fluctuations are involved in the demise of shallow marine ecosystems. Worldwide and at different times during Earth history, in-depth studies of drowning unconformities revealed that changes in nutrient input, clastic delivery, temperature, or a combination of them may be responsible for a decrease in light penetration in the water column and the progressive suffocation and poisoning of photosynthetic carbonate producers. The examination of such case examples from various stratigraphic intervals and palaeogeographical settings thus helps in identifying and hierarchizing potential triggering mechanisms for drowning unconformities. This is complemented by new data from Early Cretaceous successions from the Helvetic Alps. During this time period, the Helvetic carbonate platform developed along the northern Tethyan margin using both photozoan and heterozoan communities. Phases of healthy production were interrupted by several drowning episodes. The latter are marked in the sedimentary record by condensation and associated phosphogenesis and glauconitisation. From the earliest Valanginian to the early to late Barremian, three drowning unconformities reflect the intermittent installation of a more humid climate and subsequent enhanced trophic conditions, which first induced a switch from photozoan to heterozoan communities and then to long-lasting drowning phases. The latter encompass several sea

  14. OMI measurements of SO2 pollution over Eastern China in 2005-2008

    Science.gov (United States)

    Krotkov, N.; Pickering, K.; Witte, J.; Carn, S.; Yang, K.; Carmichael, G.; Streets, D.; Zhang, Q.; Wei, C.

    2009-05-01

    The Ozone Monitoring Instrument (OMI) on NASA Aura satellite makes global daily measurements of the total column of sulfur dioxide (SO2), a short-lived trace gas produced by fossil fuel combustion, smelting, and volcanoes. OMI seasonal to multi-year average images clearly show the world-highest consistent SO2 pollution in northeast China. China is the world's largest SO2 emitter, mostly due to the burning of high-sulfur coal in its many coal-fired power plants, which lack the technology used in many other countries to remove sulfur from smoke stack emissions. China's government has instituted nationwide measures to control SO2 emissions through the adoption of flue-gas desulfurization technology on new power plants; and even greater measures were adopted in the Beijing area in anticipation of the Olympic Games. To study the environmental effects of the emission controls we compared OMI SO2 time series over eastern China for 2005 through 2008. The time series have been done as 7-day running means of the cloud-free daily observations. By mid-March we started to see substantial periods of lower SO2 values in 2008 compared to 2007, and by mid June the 2008 values were consistently lower than 2007 and prior years. The decline is widespread with highest SO2 typically located to the south and southwest of Beijing in regions with large clusters of power plants and also around Shanghai. The decline also lasted beyond the Olympic season. We do not yet know to what extent the economic downturn in China (and reduced industrial production) contributed to lower SO2 levels in the fall of 2008. We have also compared the observed and modeled fields using University of Iowa STEM model for the period June - September 2008. The model provided SO2 vertical distributions as well as aerosol vertical profiles that were used to correct OMI operational SO2 retrievals and improve the comparisons. The OMI SO2 changes in 2008 have also been compared with the estimated changes in SO2 emissions

  15. Crown Ether Complexes of Alkali-Metal Chlorides from SO2.

    Science.gov (United States)

    Reuter, Kirsten; Rudel, Stefan S; Buchner, Magnus R; Kraus, Florian; von Hänisch, Carsten

    2017-07-18

    The structures of alkali-metal chloride SO 2 solvates (Li-Cs) in conjunction with 12-crown-4 or 1,2-disila-12-crown-4 show strong discrepancies, despite the structural similarity of the ligands. Both types of crown ethers form 1:1 complexes with LiCl to give [Li(1,2-disila-12-crown-4)(SO 2 Cl)] (1) and [Li(12-crown-4)Cl]⋅4 SO 2 (2). However, 1,2-disila-12-crown-4 proved unable to coordinate cations too large for the cavity diameter, for example, by the formation of sandwich-type complexes. As a result, 12-crown-4 reacts exclusively with the heavier alkali-metal chlorides NaCl, KCl and RbCl. Compounds [Na(12-crown-4) 2 ]Cl⋅4 SO 2 (3) and [M(12-crown-4) 2 (SO 2 )]Cl⋅4 SO 2 (4: M=K; 5: M=Rb) all showed S-coordination to the chloride ions through four SO 2 molecules. Compounds 4 and 5 additionally exhibit the first crystallographically confirmed non-bridging O,O'-coordination mode of SO 2 . Unexpectedly, the disila-crown ether supports the dissolution of RbCl and CsCl in the solvent and gives the homoleptic SO 2 -solvated alkali-metal chlorides [MCl⋅3 SO 2 ] (6: M=Rb; 7: M=Cs), which incorporate bridging μ-O,O'-coordinating moieties and the unprecedented side-on O,O'-coordination mode. All compounds were characterised by single-crystal X-ray diffraction. The crown ether complexes were additionally studied by using NMR spectroscopy, and the presence of SO 2 at ambient temperature was revealed by IR spectroscopy of the neat compounds. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  16. Technical and economical aspects of SO2 and NOx removal from flue gas by electron beam irradiation

    International Nuclear Information System (INIS)

    Turhan, S.; Karadeniz, S.; Tugluoglu, N.; Eken, M.; Oktar, O.; Ercan, I.

    2001-01-01

    The emission of sulfur dioxide (SO 2 , also SO 3 ) and nitrogen oxides (NO, NO 2 , called NO x ) from fossil fuel burning power and industrial plants is one of the major sources of environmental pollution. These pollutants are named as acid gases causing acid rain and also indirect greenhouse gases contributing greenhouse effect. Acid rain damages forest, agriculture fields and flora, and cause public health concerns in regions having a number of industrial plants. Today, many countries have started to impose industrial emission limits and this movement has generated renewed interest in finding viable and cost effective solutions to SO 2 and NO x pollution control. The conventional technologies, wet scrubbing de-SO 2 and de-NO x , now reached their full potential therefore these methods are not expected to provide further improvements in terms of efficiency or reduction in construction costs. However, new technologies are being investigated for industrial scale commercial viability. One of them is electron beam process, which is dry scrubbing process and simultaneously removes SO 2 and NO x , and useful by-product for agriculture fertilizer. In this study, the economical and technical aspects of electron beam flue gas treatment process are discussed. Because an electron accelerator facility with electron beam energy of 500 KeV and electron beam current of 20 mA will be installed at ANRTC in TURKEY

  17. Numerical simulation of flue gas purification from NOx, SO2 by electron beam

    International Nuclear Information System (INIS)

    Morgunov, V.V.; Shkilko, A.M.; Fainchtein, O.L.

    2011-01-01

    received: NO - 99.97%, NO 2 - -17.53% (the concentration growth was observed), SO 2 - 77.32% (without taking into consideration direct reaction SO 2 and NH 3 ); amount of selected species - 111; amount of selected reactions - 941. Elaborated computer code can be used for optimization of the EB flue gases purification technology, modeling kinetic mechanism of radiation-chemical processes in the flue gases, carry out numerical experiments.

  18. Effect of SO 2 on CO 2 Capture Using Liquid-like Nanoparticle Organic Hybrid Materials

    KAUST Repository

    Lin, Kun-Yi Andrew

    2013-08-15

    Liquid-like nanoparticle organic hybrid materials (NOHMs), consisting of silica nanoparticles with a grafted polymeric canopy, were synthesized. Previous work on NOHMs has revealed that CO2 capture behaviors in these hybrid materials can be tuned by modifying the structure of the polymeric canopy. Because SO2, which is another acidic gas found in flue gas, would also interact with NOHMs, this study was designed to investigate its effect on CO2 capture in NOHMs. In particular, CO2 capture capacities as well as swelling and CO2 packing behaviors of NOHMs were analyzed using thermogravimetric analyses and Raman and attenuated total reflectance (ATR) Fourier transform infrared (FTIR) spectroscopies before and after exposure of NOHMs to SO2. It was found that the SO2 absorption in NOHMs was only prominent at high SO2 levels (i.e., 3010 ppm; Ptot = 0.4 MPa) far exceeding the typical SO2 concentration in flue gas. As expected, the competitive absorption between SO2 and CO2 for the same absorption sites (i.e., ether and amine groups) resulted in a decreased CO2 capture capacity of NOHMs. The swelling of NOHMs was not notably affected by the presence of SO 2 within the given concentration range (Ptot = 0-0.68 MPa). On the other hand, SO2, owing to its Lewis acidic nature, interacted with the ether groups of the polymeric canopy and, thus, changed the CO2 packing behaviors in NOHMs. © 2013 American Chemical Society.

  19. Effect of SO 2 on CO 2 Capture Using Liquid-like Nanoparticle Organic Hybrid Materials

    KAUST Repository

    Lin, Kun-Yi Andrew; Petit, Camille; Park, Ah-Hyung Alissa

    2013-01-01

    Liquid-like nanoparticle organic hybrid materials (NOHMs), consisting of silica nanoparticles with a grafted polymeric canopy, were synthesized. Previous work on NOHMs has revealed that CO2 capture behaviors in these hybrid materials can be tuned by modifying the structure of the polymeric canopy. Because SO2, which is another acidic gas found in flue gas, would also interact with NOHMs, this study was designed to investigate its effect on CO2 capture in NOHMs. In particular, CO2 capture capacities as well as swelling and CO2 packing behaviors of NOHMs were analyzed using thermogravimetric analyses and Raman and attenuated total reflectance (ATR) Fourier transform infrared (FTIR) spectroscopies before and after exposure of NOHMs to SO2. It was found that the SO2 absorption in NOHMs was only prominent at high SO2 levels (i.e., 3010 ppm; Ptot = 0.4 MPa) far exceeding the typical SO2 concentration in flue gas. As expected, the competitive absorption between SO2 and CO2 for the same absorption sites (i.e., ether and amine groups) resulted in a decreased CO2 capture capacity of NOHMs. The swelling of NOHMs was not notably affected by the presence of SO 2 within the given concentration range (Ptot = 0-0.68 MPa). On the other hand, SO2, owing to its Lewis acidic nature, interacted with the ether groups of the polymeric canopy and, thus, changed the CO2 packing behaviors in NOHMs. © 2013 American Chemical Society.

  20. Interactive effects of high CO2 and SO2 on growth and antioxidant levels in wheat

    NARCIS (Netherlands)

    Rao, M.V.; De Kok, L.J.

    1994-01-01

    The impact of elevated CO2 and/or SO2 on the growth and antioxidant levels of wheat {Triticum aestivum L. cv. Urban) plants has been studied. High CO2 (0.7 ml I-1) significantly enhanced shoot biomass and photosynthetic capacity, while exposure to SO2 (0.14 ul I-1) resulted in a decreased shoot

  1. Co-adsorption of NH3 and SO2 on quartz : Formation of a stabilized complex

    NARCIS (Netherlands)

    Grecea, M.L.; Gleeson, M.A.; van Schaik, W.; Kleyn, A.W.; Bijkerk, Frederik

    2011-01-01

    We have investigated the co-adsorption of NH3 and SO2 on the quartz(0 0 0 1) surface by TPD and RAIRS. A surface complex is formed as a result of various relative exposures of NH3 and SO2, irrespective of dosage order. However, the relative molecular composition of the complex is dependent on the

  2. 40 CFR 60.4385 - How are excess emissions and monitoring downtime defined for SO2?

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 6 2010-07-01 2010-07-01 false How are excess emissions and monitoring downtime defined for SO2? 60.4385 Section 60.4385 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... downtime defined for SO2? If you choose the option to monitor the sulfur content of the fuel, excess...

  3. Impact of SO2 emissions cap on Phase I compliance decisions

    International Nuclear Information System (INIS)

    Bissell, P.E.; Fink, C.E.; Koch, B.J.; Chomka, P.A.

    1990-01-01

    The SO 2 emissions cap provisions of impending clean air legislation will dramatically affect Phase I and Phase II compliance decisions by electric utilities. Technology-based SO 2 reduction alternatives could become the keystone of most compliance strategies as utilities attempt to achieve lower and lower SO 2 emission rates. Compliance with the Phase II emissions cap will require technological solutions for many utilities which must meet system-wide SO 2 emission rates well below those achievable with low-sulfur eastern coals and, in many instances, western coals. The emissions cap provision, however, will also induce more scrubbing during the Phase I compliance period. The power generation dispatch capability of a hypothetical utility system was simulated to study the impacts of an SO 2 emission cap on compliance strategies in Phase I. The effects of the cap were quantified for generation costs, total SO 2 emissions, and effective emission rates. The results show that achieving compliance by installing state-of-the-art high SO 2 removal scrubbers becomes increasingly attractive as utilities become constrained under the SO 2 cap, even in Phase I

  4. System for recovery of CO2 from flue gases containing SO2

    International Nuclear Information System (INIS)

    Sears, J. T.; Anada, H. R.

    1985-01-01

    An improved system for recovering CO 2 from flue gases containing SO 2 at low CO 2 partial pressure. The system includes the use of K 2 CO 3 as the solvent, regeneration of the solvent, and removal of SO 2 and SO 4

  5. Impact of SO(2) on Arabidopsis thaliana transcriptome in wildtype and sulfite oxidase knockout plants analyzed by RNA deep sequencing.

    Science.gov (United States)

    Hamisch, Domenica; Randewig, Dörte; Schliesky, Simon; Bräutigam, Andrea; Weber, Andreas P M; Geffers, Robert; Herschbach, Cornelia; Rennenberg, Heinz; Mendel, Ralf R; Hänsch, Robert

    2012-12-01

    High concentrations of sulfur dioxide (SO(2) ) as an air pollutant, and its derivative sulfite, cause abiotic stress that can lead to cell death. It is currently unknown to what extent plant fumigation triggers specific transcriptional responses. To address this question, and to test the hypothesis that sulfite oxidase (SO) is acting in SO(2) detoxification, we compared Arabidopsis wildtype (WT) and SO knockout lines (SO-KO) facing the impact of 600 nl l(-1) SO(2) , using RNAseq to quantify absolute transcript abundances. These transcriptome data were correlated to sulfur metabolism-related enzyme activities and metabolites obtained from identical samples in a previous study. SO-KO plants exhibited remarkable and broad regulative responses at the mRNA level, especially in transcripts related to sulfur metabolism enzymes, but also in those related to stress response and senescence. Focusing on SO regulation, no alterations were detectable in the WT, whereas in SO-KO plants we found up-regulation of two splice variants of the SO gene, although this gene is not functional in this line. Our data provide evidence for the highly specific coregulation between SO and sulfur-related enzymes like APS reductase, and suggest two novel candidates for involvement in SO(2) detoxification: an apoplastic peroxidase, and defensins as putative cysteine mass storages. © 2012 The Authors. New Phytologist © 2012 New Phytologist Trust.

  6. SO2 photoexcitation mechanism links mass-independent sulfur isotopic fractionation in cryospheric sulfate to climate impacting volcanism

    Science.gov (United States)

    Hattori, Shohei; Schmidt, Johan A.; Johnson, Matthew S.; Danielache, Sebastian O.; Yamada, Akinori; Ueno, Yuichiro; Yoshida, Naohiro

    2013-01-01

    Natural climate variation, such as that caused by volcanoes, is the basis for identifying anthropogenic climate change. However, knowledge of the history of volcanic activity is inadequate, particularly concerning the explosivity of specific events. Some material is deposited in ice cores, but the concentration of glacial sulfate does not distinguish between tropospheric and stratospheric eruptions. Stable sulfur isotope abundances contain additional information, and recent studies show a correlation between volcanic plumes that reach the stratosphere and mass-independent anomalies in sulfur isotopes in glacial sulfate. We describe a mechanism, photoexcitation of SO2, that links the two, yielding a useful metric of the explosivity of historic volcanic events. A plume model of S(IV) to S(VI) conversion was constructed including photochemistry, entrainment of background air, and sulfate deposition. Isotopologue-specific photoexcitation rates were calculated based on the UV absorption cross-sections of 32SO2, 33SO2, 34SO2, and 36SO2 from 250 to 320 nm. The model shows that UV photoexcitation is enhanced with altitude, whereas mass-dependent oxidation, such as SO2 + OH, is suppressed by in situ plume chemistry, allowing the production and preservation of a mass-independent sulfur isotope anomaly in the sulfate product. The model accounts for the amplitude, phases, and time development of Δ33S/δ34S and Δ36S/Δ33S found in glacial samples. We are able to identify the process controlling mass-independent sulfur isotope anomalies in the modern atmosphere. This mechanism is the basis of identifying the magnitude of historic volcanic events. PMID:23417298

  7. Standard practice for monitoring atmospheric SO2 using the sulfation plate technique

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    1997-01-01

    1.1 This practice covers a weighted average effective SO2 level for a 30-day interval through the use of the sulfation plate method, a technique for estimating the effective SO2 content of the atmosphere, and especially with regard to the atmospheric corrosion of stationary structures or panels. This practice is aimed at determining SO2 levels rather than sulfuric acid aerosol or acid precipitation. 1.2 The results of this practice correlate approximately with volumetric SO2 concentrations, although the presence of dew or condensed moisture tends to enhance the capture of SO2 into the plate. 1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

  8. SO2 frost - UV-visible reflectivity and Io surface coverage

    Science.gov (United States)

    Nash, D. B.; Fanale, F. P.; Nelson, R. M.

    1980-01-01

    The reflectance spectrum in the range 0.24-0.85 microns of SO2 frost is measured in light of the discovery of SO2 gas in the atmosphere of Io and the possible discovery of the frost on its surface. Frost deposits up to 1.5 mm thick were grown in vacuum at 130 K and bi-directional reflectance spectra were obtained. Typical SO2 frost is found to exhibit very low reflectivity (2-5%) at 0.30 microns, rising steeply at 0.32 microns to attain a maximum reflectivity (75-80%) at 4.0 microns and uniformly high reflectivity throughout the visible and near infrared. Comparison with the full disk spectrum of Io reveals that no more than 20% of the surface can be covered with optically thick SO2 frost. Combinations of surface materials including SO2 frost which can produce the observed spectrum are indicated.

  9. Monitoring so2 emission at the Soufriere Hills volcano: Implications for changes in eruptive conditions

    Science.gov (United States)

    Young, S.R.; Francis, P.W.; Barclay, J.; Casadevall, T.J.; Gardner, C.A.; Darroux, B.; Davies, M.A.; Delmelle, P.; Norton, G.E.; Maciejewski, A.J.H.; Oppenheimer, C.M.M.; Stix, J.; Watson, I.M.

    1998-01-01

    Correlation spectrometer measurements of sulfur dioxide (SO2) emission rates during the current eruption of the Soufriere Hills volcano, Montserrat, have contributed towards identifying different phases of volcanic activity. SO2 emission rate has increased from 550 td-1 (>6.4 kgs-1) after July 1996, with the uncertainty associated with any individual measurement ca. 30%. Significantly enhanced SO2 emission rates have been identified in association with early phreatic eruptions (800 td-1 (9.3 kgs-1)) and episodes of vigorous dome collapse and pyroclastic flow generation (900 to 1500 td-1 (10.4 to 17.4 kgs-1)). SO2 emission rate has proved a useful proxy measurement for magma production rate. Observed SO2 emission rates are significantly higher than those inferred from analyses of glass inclusions in phenocrysts, implying the existence of a S-rich magmatic vapour phase.

  10. Are there SO2 externality costs beyond the Clean Air Act Amendments of 1990?

    International Nuclear Information System (INIS)

    Sanghi, A.; Joseph, A.L.

    1992-01-01

    Inclusion of environmental externality costs in the selection of utility resources has become a reality in New York, Massachusetts, Nevada and California. Soon several other jurisdictions are likely to join these states in using environmental externality costs in decision-making. The consideration of environmental externalities are bound to profoundly affect utility decision-making in the future. So far attention has focused largely on air emission externalities of SO 2 , NO x and CO 2 . However, the recent Clean Air Act Amendments (CAAA) will reduce SO 2 emissions from utilities by about 50 percent. With such a large reduction in SO 2 loading, the question has been raised as to the need to further consider SO 2 externality costs in decision-making. This paper comments on this issue. By using generation and emission data from New York utilities, the paper shows that SO 2 emission externalities exist even after complying with requirements of the CAAA

  11. The determinants of atmospheric SO2 concentrations. Reconsidering the environmental Kuznets curve

    International Nuclear Information System (INIS)

    Kaufmann, Robert K.; Davidsdottir, Brynhildur; Garnham, Sophie; Pauly, Peter

    1998-01-01

    This analysis explores the effects of income and the spatial intensity of economic activity on the atmospheric concentration of sulfur dioxide. The results indicate that there is a U-shaped relation between income and atmospheric concentration of SO 2 and an inverted U-shaped relation between the spatial intensity of economic activity and SO 2 concentrations. These results suggest that the spatial intensity of economic activity, rather than income, provides the impetus for policies and technologies that reduce SO 2 emissions. Based on this result, the atmospheric concentration of SO 2 in developing nations may decline faster than indicated by previous analyses. The potential for this decline depends on the rate at which income grows relative to population. The trade-off between the effects of income gains and the spatial intensity of economic activity on the atmospheric concentration of SO 2 is consistent with the notion that environmental problems can be ameliorated by slowing population growth and increasing income levels

  12. New discoveries enabled by OMI SO2 measurements and future missions

    Science.gov (United States)

    Krotkov, Nickolay

    2010-05-01

    The Ozone Monitoring Instrument (OMI) on NASA Aura satellite makes global daily measurements of the total column of sulfur dioxide (SO2), a short-lived trace gas produced by fossil fuel combustion, smelting, and volcanoes. This talk highlights most recent science results enabled by using OMI SO2 data. OMI daily contiguous volcanic SO2 data continue 25+ climatic record by its predecessors (Total Ozone mapping Spectrometers 1978-2005), but higher SO2 sensitivity allows measuring volcanic plumes for a longer time as well as measuring passive volcanic degassing from space. New algorithm development allows direct estimating of SO2 plume heights to refine SO2 tonnages in largest volcanic plumes important for climate applications. Quantitatively, anthropogenic SO2 is more difficult to measure from space, since ozone absorption and Rayleigh scattering reduce sensitivity to pollutants in the lower troposphere. OMI data first enabled daily detection of SO2 burdens from individual smelters as well as observed SO2 pollution lofting from boundary layer and long-range transport in free troposphere. Interplay between volcanic and anthropogenic SO2 emissions resulted in highly variable SO2 pollution levels in Peru and Mexico City. We have updated our copper smelter analysis, which showed interesting new trends. Combining OMI data with trajectory models and aerosol/cloud measurements by A-train sensors (MODIS, CALIPSO) allowed tracking long-range transport of volcanic and anthropogenic aerosol/SO2 plumes. These studies placed new constraints on conversion rates of SO2 to sulfate at different heights from free troposphere to the lower stratosphere. We describe new techniques for spatial and time averaging that have been used to determine the global distribution of anthropogenic SO2 burdens, and the efficacy of abatement strategies. OMI seasonal to multi-year average images clearly show the world-highest consistent SO2 pollution in eastern China, mostly due to the burning of high

  13. Interactive methods to involve users into workspace design process

    DEFF Research Database (Denmark)

    Souza da Conceição, Carolina; Broberg, Ole; Banke, Palle

    2013-01-01

    This paper addresses the question of whether the use of a combination of interactive methods involving workers can lead to a useful input to the (re)design of their workspace. The workbook and the layout design game methods were tested, and a comparison between their use and the ergonomic analysi...

  14. Parental Involvement and Children's School Achievement: Evidence for Mediating Processes

    Science.gov (United States)

    Rogers, Maria A.; Theule, Jennifer; Ryan, Bruce A.; Adams, Gerald R.; Keating, Leo

    2009-01-01

    This study used path analytic techniques and an ecological framework to examine the association between children's perceptions of their parents' educational involvement, children's personal characteristics, and their school achievement. Fathers' academic pressure was predictive of lower achievement, whereas mothers' encouragement and support…

  15. The uptake of SO2 on Saharan dust: a flow tube study

    Directory of Open Access Journals (Sweden)

    J. W. Adams

    2005-01-01

    Full Text Available The uptake of SO2 onto Saharan mineral dust from the Cape Verde Islands was investigated using a coated wall flow tube coupled to a mass spectrometer. The rate of loss of SO2 to the dust coating was measured and uptake coefficients were determined using the measured BET surface area of the sample. The uptake of SO2, with an initial concentration between (2-40x1010molecule cm-3 (0.62-12 µTorr, was found to be strongly time dependent over the first few hundred seconds of an experiment, with an initial uptake γ0,BET of (6.6±0.8x10-5 (298 K, declining at longer times. The amount of SO2 adsorbed on the dust samples was measured over a range of SO2 concentrations and mineral dust loadings. The uptake of SO2 was found to be up to 98% irreversible over the timescale of these investigations. Experiments were also performed at 258 K, at a relative humidity of 27% and at 298 K in the presence of ozone. The initial uptake and the amount of SO2 taken up per unit area of BET dust surface was the same within error, irrespective of the conditions used; however the presence of ozone reduced the amount of SO2 released back into the gas-phase per unit area once exposure of the surface ended. Multiple uptakes to the same surface revealed a loss of surface reactivity, which did not return if the samples were exposed to gas-phase water, or left under vacuum overnight. A mechanism which accounts for the observed uptake behaviour is proposed and numerically modelled, allowing quantitative estimates of the rate and amount of SO2 removal in the atmosphere to be estimated. Removal of SO2 by mineral dust is predicted to be significant at high dust loadings.

  16. SO2 plume height retrieval from direct fitting of GOME-2 backscattered radiance measurements

    Science.gov (United States)

    van Gent, J.; Spurr, R.; Theys, N.; Lerot, C.; Brenot, H.; Van Roozendael, M.

    2012-04-01

    The use of satellite measurements for SO2 monitoring has become an important aspect in the support of aviation control. Satellite measurements are sometimes the only information available on SO2 concentrations from volcanic eruption events. The detection of SO2 can furthermore serve as a proxy for the presence of volcanic ash that poses a possible hazard to air traffic. In that respect, knowledge of both the total vertical column amount and the effective altitude of the volcanic SO2 plume is valuable information to air traffic control. The Belgian Institute for Space Aeronomy (BIRA-IASB) hosts the ESA-funded Support to Aviation Control Service (SACS). This system provides Volcanic Ash Advisory Centers (VAACs) worldwide with near real-time SO2 and volcanic ash data, derived from measurements from space. We present results from our algorithm for the simultaneous retrieval of total vertical columns of O3 and SO2 and effective SO2 plume height from GOME-2 backscattered radiance measurements. The algorithm is an extension to the GODFIT direct fitting algorithm, initially developed at BIRA-IASB for the derivation of improved total ozone columns from satellite data. The algorithm uses parameterized vertical SO2 profiles which allow for the derivation of the peak height of the SO2 plume, along with the trace gas total column amounts. To illustrate the applicability of the method, we present three case studies on recent volcanic eruptions: Merapi (2010), Grímsvotn (2011), and Nabro (2011). The derived SO2 plume altitude values are validated with the trajectory model FLEXPART and with aerosol altitude estimations from the CALIOP instrument on-board the NASA A-train CALIPSO platform. We find that the effective plume height can be obtained with a precision as fine as 1 km for moderate and strong volcanic events. Since this is valuable information for air traffic, we aim at incorporating the plume height information in the SACS system.

  17. Hydrophobic task-specific ionic liquids: synthesis, properties and application for the capture of SO2.

    Science.gov (United States)

    Tian, Shidong; Hou, Yucui; Wu, Weize; Ren, Shuhang; Qian, Jianguo

    2014-08-15

    The capture of SO2 by ionic liquids (ILs) has drawn much attention all over the world. However, ILs can absorb not only SO2 but also water from flue gas. The removal of water from ILs is necessary for reusing the absorbent. In order to reduce the energy costs of removing water, it would be helpful to weaken the interactions between ILs and water. In this work, two kinds of hydrophobic task-specific ILs, 1-(2-diethyl-aminoethyl)-3-methylimidazolium hexafluorophosphate ([Et2NEmim] [PF6]) and 1-(2-diethyl-aminoethyl)-1-methylpyrrolidinium hexafluorophosphate ([Et2NEmpyr][PF6]), were designed and synthesized. Thermal stability and physical properties of the ILs were studied. Furthermore, the application of the ILs for the capture of SO2 and the absorption mechanism were systematically investigated. It has been found that both of the ILs are immiscible with water, and [Et2NEmim][PF6] has much lower viscosity, much higher thermal stability and much higher SO2 absorption rate than [Et2NEmpyr][PF6]. [Et2NEmim][PF6] shows high SO2 absorption capacities up to 2.11 mol SO2 per mole IL (pure SO2) and 0.94 mol SO2 per mole IL (3% SO2) under hydrous conditions at 30 °C. The result suggests that [Et2NEmim][PF6] is a promising recyclable absorbent for the capture of SO2. Copyright © 2014 Elsevier B.V. All rights reserved.

  18. SO2 over Central China: Measurements, Numerical Simulations and the Tropospheric Sulfur Budget

    Science.gov (United States)

    He, Hao; Li, Can; Loughner, Christopher P.; Li, Zhangqing; Krotkov, Nickolay A.; Yang, Kai; Wang, Lei; Zheng, Youfei; Bao, Xiangdong; Zhao, Guoqiang; hide

    2012-01-01

    SO2 in central China was measured in situ from an aircraft and remotely using the Ozone Monitoring Instrument (OMI) from the Aura satellite; results were used to develop a numerical tool for evaluating the tropospheric sulfur budget - sources, sinks, transformation and transport. In April 2008, measured ambient SO2 concentrations decreased from approx.7 ppbv near the surface to approx. 1 ppbv at 1800 m altitude (an effective scale height of approx.800 m), but distinct SO2 plumes were observed between 1800 and 4500 m, the aircraft's ceiling. These free tropospheric plumes play a major role in the export of SO2 and in the accuracy of OMI retrievals. The mean SO2 column contents from aircraft measurements (0.73 DU, Dobson Units) and operational OMI SO2 products (0.63+/-0.26 DU) were close. The OMI retrievals were well correlated with in situ measurements (r = 0.84), but showed low bias (slope = 0.54). A new OMI retrieval algorithm was tested and showed improved agreement and bias (r = 0.87, slope = 0.86). The Community Multiscale Air Quality (CMAQ) model was used to simulate sulfur chemistry, exhibiting reasonable agreement (r = 0.62, slope = 1.33) with in situ SO2 columns. The mean CMAQ SO2 loading over central and eastern China was 54 kT, approx.30% more than the estimate from OMI SO2 products, 42 kT. These numerical simulations, constrained by observations, indicate that ",50% (35 to 61 %) of the anthropogenic sulfur emissions were transported downwind, and the overall lifetime of tropospheric SO2 was 38+/-7 h.

  19. Intra-dialytic blood oxygen saturation (SO2): association with dialysis hypotension (the SOGLIA Study).

    Science.gov (United States)

    Mancini, E; Perazzini, C; Gesualdo, L; Aucella, F; Limido, A; Scolari, F; Savoldi, S; Tramonti, M; Corazza, L; Atti, M; Severi, S; Bolasco, P; Santoro, A

    2017-12-01

    Intradialytic hypotension (IDH) has a dramatic impact on the main outcomes of dialysis patients. Early warning of hemodynamic worsening during dialysis would enable preventive measures to be taken. Blood oxygen saturation (SO 2 ) is used for hemodynamic monitoring in the critical care setting and may provide useful information about IDH onset. To evaluate whether short- and medium-term variations in the SO 2 signal (ST-SO 2var , MT-SO 2var ,) during dialysis are a predictor of IDH. In this 3-month observational cohort study, 51 hypotension-prone chronic hemodialysis (HD) patients, with vascular access by arteriovenous fistula (AVF) or central venous catheter (CVC), were enrolled. Continuous non-invasive blood SO 2 was monitored (fc = 0.2 Hz) by an optical sensor on the arterial line of the extracorporeal circulation; blood pressure (every 30 min), symptoms and their time of appearance were noted. Predictive power of IDH was expressed by the area under curve (AUC) sensitivity and specificity based on intradialytic variations in SO 2 . A total of 1290 HD sessions were analyzed. Overall, off-line ST-SO 2var analysis proved able to correctly predict IDH in 67 % of the sessions where IDH occurred. The best predictive performance was found in the presence of highly arterialized AVF (SO 2  > 95 %) (75 % sensitivity; AUC 0.825; p < 0.05). On the contrary, in sessions with CVC, IDH prediction proved more efficient by MT-SO 2var (AUC 0.575; p = 0.01). Intradialytic SO 2 variability could be a valid parameter to detect in advance the hemodynamic worsening that precedes IDH. Appropriate timely intervention could help prevent IDH onset.

  20. [Effect of SO2 volume fraction in flue gas on the adsorption behaviors adsorbed by ZL50 activated carbon and kinetic analysis].

    Science.gov (United States)

    Gao, Ji-xian; Wang, Tie-feng; Wang, Jin-fu

    2010-05-01

    The influence of SO2 dynamic adsorption behaviors using ZL50 activated carbon for flue gas desulphurization and denitrification under different SO2 volume fraction was investigated experimentally, and the kinetic analysis was conducted by kinetic models. With the increase of SO2 volume fraction in flue gas, the SO2 removal ratio and the activity ratio of ZL50 activated carbon decreased, respectively, and SO2 adsorption rate and capacity increased correspondingly. The calculated results indicate that Bangham model has the best prediction effect, the chemisorption processes of SO2 was significantly affected by catalytic oxidative reaction. The adsorption rate constant of Lagergren's pseudo first order model increased with the increase of inlet SO, volume fraction, which indicated that catalytic oxidative reaction of SO2 adsorbed by ZL50 activated carbon may be the rate controlling step in earlier adsorption stage. The Lagergren's and Bangham's initial adsorption rate were deduced and defined, respectively. The Ho's and Elovich's initial adsorption rate were also deduced in this paper. The Bangham's initial adsorption rate values were defined in good agreement with those of experiments. The defined Bangham's adsorptive reaction kinetic model can describe the SO2 dynamic adsorption rate well. The studied results indicated that the SO2 partial order of initial reaction rate was one or adjacent to one, while the O2 and water vapor partial order of initial reaction rate were constants ranging from 0.15-0.20 and 0.45-0.50, respectively.

  1. Impacts of Four SO2 Oxidation Pathways on Wintertime Sulfate Concentrations

    Science.gov (United States)

    Sarwar, G.; Fahey, K.; Zhang, Y.; Kang, D.; Mathur, R.; Xing, J.; Wei, C.; Cheng, Y.

    2017-12-01

    Air quality models tend to under-estimate winter-time sulfate concentrations compared to observed data. Such under-estimations are particularly acute in China where very high concentrations of sulfate have been measured. Sulfate is produced by oxidation of sulfur dioxide (SO2) in gas-phase by hydroxyl radical and in aqueous-phase by hydrogen peroxide, ozone, etc. and most air quality models employ such typical reactions. Several additional SO2 oxidation pathways have recently been proposed. Heterogeneous reaction on dust has been suggested to be an important sink for SO2. Oxidation of SO2 on fine particles in presence of nitrogen dioxide (NO2) and ammonia (NH3) at high relative humidity has been implicated for sulfate formation in Chinese haze and London fog. Reactive nitrogen chemistry in aerosol water has also been suggested to produce winter-time sulfate in China. Specifically, high aerosol water can trap SO2 which can be subsequently oxidized by NO2 to form sulfate. Aqueous-phase (in-cloud) oxidation of SO2 by NO2 can also produce sulfate. Here, we use the hemispheric Community Multiscale Air Quality (CMAQ) modeling system to examine the potential impacts of these SO2 oxidation pathways on sulfate formation. We use anthropogenic emissions from the Emissions Database for Global Atmospheric Research and biogenic emissions from Global Emissions InitiAtive. We performed simulations without and with these SO2 oxidation pathways for October-December of 2014 using meteorological fields obtained from the Weather Research and Forecasting model. The standard CMAQ model contains one gas-phase chemical reaction and five aqueous-phase chemical reactions for SO2 oxidation. We implement four additional SO2 oxidation pathways into the CMAQ model. Our preliminary results suggest that the dust chemistry enhances mean sulfate over parts of China and Middle-East, the in-cloud SO2 oxidation by NO2 enhances sulfate over parts of western Europe, oxidation of SO2 by NO2 and NH3 on

  2. Across frequency processes involved in auditory detection of coloration

    DEFF Research Database (Denmark)

    Buchholz, Jörg; Kerketsos, P

    2008-01-01

    filterbank was designed to approximate auditory filter-shapes measured by Oxenham and Shera [JARO, 2003, 541-554], derived from forward masking data. The results of the present study demonstrate that a “purely” spectrum-based model approach can successfully describe auditory coloration detection even at high......When an early wall reflection is added to a direct sound, a spectral modulation is introduced to the signal's power spectrum. This spectral modulation typically produces an auditory sensation of coloration or pitch. Throughout this study, auditory spectral-integration effects involved in coloration...... detection are investigated. Coloration detection thresholds were therefore measured as a function of reflection delay and stimulus bandwidth. In order to investigate the involved auditory mechanisms, an auditory model was employed that was conceptually similar to the peripheral weighting model [Yost, JASA...

  3. Research Education: Perspectives and subjective processes involved in educational research

    Directory of Open Access Journals (Sweden)

    Harm H. Tillema

    2009-10-01

    Full Text Available Educational research acknowledges that researcher’s beliefs and training play a role in framing the outcomes of any study. Research not only consists of defining objectives and following certain methods (search but also of making decisions over the steps taking during the inquiry process (research.Establishing a conceptual framework to guide actions on the subjective processes in research is then crucial to control them. With that purpose in mind we offer researchers and Teacher Educators a heuristic tool to be conscious on the risks that can be taken when immersed in research interpretative process. This instrument could be utilised in PhD programs, masters and research projects.

  4. SU-E-T-326: The Oxygen Saturation (SO2) and Breath-Holding Time Variation Applied Active Breathing Control (ABC)

    Energy Technology Data Exchange (ETDEWEB)

    Gong, G; Yin, Y [Shandong Cancer Hospital, Jinan, Shandong (China)

    2014-06-01

    Purpose: To study the oxygen saturation (SO2) and breath-holding time variation applied active breathing control (ABC) in radiotherapy of tumor. Methods: 24 volunteers were involved in our trials, and they all did breath-holding motion assisted by ELEKTA Active Breathing Coordinator 2.0 for 10 times respectively. And the patient monitor was used to observe the oxygen saturation (SO2) variation. The variation of SO2, and length of breath-holding time and the time for recovering to the initial value of SO2 were recorded and analyzed. Results: (1) The volunteers were divided into two groups according to the SO2 variation in breath-holding: A group, 14 cases whose SO2 reduction were more than 2% (initial value was 97% to 99%, while termination value was 91% to 96%); B group, 10 cases were less than 2% in breath-holding without inhaling oxygen. (2) The interfraction breath holding time varied from 8 to 20s for A group compared to the first breath-holding time, and for B group varied from 4 to 14s. (3) The breathing holding time of B group prolonged mean 8s, compared to A group. (4) The time for restoring to the initial value of SO2 was from 10s to 30s. And the breath-holding time shortened obviously for patients whose SO2 did not recover to normal. Conclusion: It is very obvious that the SO2 reduction in breath-holding associated with ABC for partial people. It is necessary to check the SO2 variation in breath training, and enough time should be given to recover SO2.

  5. Acute myocardial infarction and COPD attributed to ambient SO2 in Iran.

    Science.gov (United States)

    Khaniabadi, Yusef Omidi; Daryanoosh, Seyed Mohammad; Hopke, Philip K; Ferrante, Margherita; De Marco, Alessandra; Sicard, Pierre; Oliveri Conti, Gea; Goudarzi, Gholamreza; Basiri, Hassan; Mohammadi, Mohammad Javad; Keishams, Fariba

    2017-07-01

    Acute myocardial infarction (MI) and chronic obstructive pulmonary disease (COPD) are important diseases worldwide. Inhalation is the major route of short-term exposure to air sulfur dioxide (SO 2 ) that negatively affect human health. The objective of this study was to estimate the health effects of short-term exposure to SO 2 in Khorramabad, Iran using the AirQ software developed by the World Health Organization (WHO). Daily mean SO 2 concentrations were used as the estimates of human short-term exposure and allow calculation of the attributable excess relative risk of an acute MI and hospital admissions due to COPD (HACOPD). The annual mean SO 2 concentration in Khorramabad was 51.33µg/m 3 . Based on the relative risk (RR) and baseline incidence (BI) approach of WHO, an increased risk of 2.7% (95% CI: 1.1-4.2%) of acute MI and 2.0% (95% CI: 0-4.6%) of HACOPD, respectively, were attributed to a 10µg/m 3 SO 2 increase. Since the geographic, demographic, and climatic characteristics are different from the areas in which the risk relationships were developed and not evaluated here, further investigations will be needed to fully quantify other health impacts of SO 2 . A decreased risk for MIs and COPD attributable to SO 2 could be achieved if mitigation strategies and measures are implemented to reduce the exposure. Copyright © 2017. Published by Elsevier Inc.

  6. SO2 columns over China: Temporal and spatial variations using OMI and GOME-2 observations

    International Nuclear Information System (INIS)

    Huanhuan, Yan; Liangfu, Chen; Lin, Su; Jinhua, Tao; Chao, Yu

    2014-01-01

    Enhancements of SO 2 column amounts due to anthropogenic emission sources over China were shown in this paper by using OMI and GOME-2 observations. The temporal and spatial variations of SO 2 columns over China were analyzed for the time period 2005–2010. Beijing and Chongqing showed a high concentration in the SO 2 columns, attributable to the use of coal for power generation in China and the characteristic of terrain and meteorology. The reduction of SO 2 columns over Beijing and surrounding provinces in 2008 was observed by OMI, which confirms the effectiveness of strict controls on pollutant emissions and motor vehicle traffic before and during 2008 Olympic and Paralympic Games. The SO 2 columns over China from GOME-2 (0.2–0.5 DU) were lower than those from OMI (0.6–1 DU), but both showed a decrease in SO 2 columns over northern China since 2008 (except an increase in OMI SO 2 in 2010)

  7. A decade of global volcanic SO2 emissions measured from space

    Science.gov (United States)

    Carn, S. A.; Fioletov, V. E.; McLinden, C. A.; Li, C.; Krotkov, N. A.

    2017-03-01

    The global flux of sulfur dioxide (SO2) emitted by passive volcanic degassing is a key parameter that constrains the fluxes of other volcanic gases (including carbon dioxide, CO2) and toxic trace metals (e.g., mercury). It is also a required input for atmospheric chemistry and climate models, since it impacts the tropospheric burden of sulfate aerosol, a major climate-forcing species. Despite its significance, an inventory of passive volcanic degassing is very difficult to produce, due largely to the patchy spatial and temporal coverage of ground-based SO2 measurements. We report here the first volcanic SO2 emissions inventory derived from global, coincident satellite measurements, made by the Ozone Monitoring Instrument (OMI) on NASA’s Aura satellite in 2005-2015. The OMI measurements permit estimation of SO2 emissions from over 90 volcanoes, including new constraints on fluxes from Indonesia, Papua New Guinea, the Aleutian Islands, the Kuril Islands and Kamchatka. On average over the past decade, the volcanic SO2 sources consistently detected from space have discharged a total of ~63 kt/day SO2 during passive degassing, or ~23 ± 2 Tg/yr. We find that ~30% of the sources show significant decadal trends in SO2 emissions, with positive trends observed at multiple volcanoes in some regions including Vanuatu, southern Japan, Peru and Chile.

  8. Lessons Learned from OMI Observations of Point Source SO2 Pollution

    Science.gov (United States)

    Krotkov, N.; Fioletov, V.; McLinden, Chris

    2011-01-01

    The Ozone Monitoring Instrument (OMI) on NASA Aura satellite makes global daily measurements of the total column of sulfur dioxide (SO2), a short-lived trace gas produced by fossil fuel combustion, smelting, and volcanoes. Although anthropogenic SO2 signals may not be detectable in a single OMI pixel, it is possible to see the source and determine its exact location by averaging a large number of individual measurements. We describe new techniques for spatial and temporal averaging that have been applied to the OMI SO2 data to determine the spatial distributions or "fingerprints" of SO2 burdens from top 100 pollution sources in North America. The technique requires averaging of several years of OMI daily measurements to observe SO2 pollution from typical anthropogenic sources. We found that the largest point sources of SO2 in the U.S. produce elevated SO2 values over a relatively small area - within 20-30 km radius. Therefore, one needs higher than OMI spatial resolution to monitor typical SO2 sources. TROPOMI instrument on the ESA Sentinel 5 precursor mission will have improved ground resolution (approximately 7 km at nadir), but is limited to once a day measurement. A pointable geostationary UVB spectrometer with variable spatial resolution and flexible sampling frequency could potentially achieve the goal of daily monitoring of SO2 point sources and resolve downwind plumes. This concept of taking the measurements at high frequency to enhance weak signals needs to be demonstrated with a GEOCAPE precursor mission before 2020, which will help formulating GEOCAPE measurement requirements.

  9. Changes in SO2 and NO2 Pollution over the Past Decade Observed by Aura OMI

    Science.gov (United States)

    Krotkov, N. A.; Li, C.; Lamsal, L. N.; Celarier, E. A.; Marchenko, S. V.; Swartz, W.; Bucsela, E. J.; Fioletov, V.; McLinden, C. A.; Joiner, J.; Bhartia, P. K.; Duncan, B. N.; Dickerson, R. R.

    2014-12-01

    The Ozone Monitoring Instrument (OMI), a NASA partnership with the Netherlands and Finland, flies on the EOS Aura satellite and uses reflected sunlight to measure two critical atmospheric trace gases, nitrogen dioxide (NO2) and sulfur dioxide (SO2), characterizing daily air quality. Both gases and the secondary pollutants they produce (particulate matter, PM2.5, and tropospheric ozone) are among USEPA designated criteria pollutants, posing serious threats to human health and the environment (e.g., acid rain, plant damage, and reduced visibility). A new generation of the OMI standard SO2 and NO2 products (based on critically improved DOAS spectral fitting for NO2 and innovative Principal Component Analysis method for SO2) provides a valuable dataset for studying anthropogenic pollution on local to global scales. Here we highlight some of the OMI observed long-term changes in air quality over several regions. Over the US, average NO2 and SO2 pollution levels have decreased dramatically as a result of both technological improvements (e.g., catalytic converters on cars) and stricter regulations of emissions. We see continued decline in NO2 and SO2 pollution over Europe. Over China OMI observed a ~ 60% increase in NO2 pollution between 2005 and 2013, despite a temporary reversal of the growing trend due to both 2008 Olympic Games and the economic recession in 2009. Chinese SO2 pollution seems to have stabilized since peaking in 2007, probably due to government efforts to curb SO2 emissions from the power sector. We have also observed large increases in both SO2 and NO2 pollution particularly in Eastern India where a number of new large coal power plants have been built in recent years. We expect that further improvements in the OMI NO2 and SO2 products will allow more robust quantification of long-term trends in local to global air quality.

  10. The Interaction between Personality, Social Network Position and Involvement in Innovation Process

    NARCIS (Netherlands)

    E. Dolgova (Evgenia); W. van Olffen (Woody); F.A.J. van den Bosch (Frans); H.W. Volberda (Henk)

    2010-01-01

    textabstractAbstract This dissertation proposal investigates how personality and individuals’ social network position affect individuals’ involvement into the innovation process. It posits that people would feel inclined to become involved into the different phases of the innovation process

  11. Processes involved in pion capture in hydrogen-containing molecules

    International Nuclear Information System (INIS)

    Horvath, D.

    1983-03-01

    A systematic analysis is presented of the possible elementary processes determining the fate of negative pions stopped in hydrogen-containing samples. Using a phenomenological description in comparison with the available experimental information on pion capture in hydrogen, it is shown that the formation and decay of pπ - atoms in compounds Zsub(m)Hsub(n) are determined mainly by the processes of Auger capture in a molecular orbit ZHπ - , transition from molecular to atomic orbit, transfer of pions to atoms Z in collisions pπ - +Z, and nuclear capture in collisions pπ - +H. The recent assumption of a considerable role of the processes of radiative atomic capture in bound hydrogen atoms, nuclear capture of pions by protons from the molecular state ZHπ - , or 'inner' transfer of the pion via tunnelling through the bond Z-H is not supported by the theory and contradicts the experimental data

  12. Using CATS Near-Real-time Lidar Observations to Monitor and Constrain Volcanic Sulfur Dioxide (SO2) Forecasts

    Science.gov (United States)

    Hughes, E. J.; Yorks, J.; Krotkov, N. A.; da Silva, A. M.; Mcgill, M.

    2016-01-01

    An eruption of Italian volcano Mount Etna on 3 December 2015 produced fast-moving sulfur dioxide (SO2) and sulfate aerosol clouds that traveled across Asia and the Pacific Ocean, reaching North America in just 5 days. The Ozone Profiler and Mapping Suite's Nadir Mapping UV spectrometer aboard the U.S. National Polar-orbiting Partnership satellite observed the horizontal transport of the SO2 cloud. Vertical profiles of the colocated volcanic sulfate aerosols were observed between 11.5 and 13.5 km by the new Cloud Aerosol Transport System (CATS) space-based lidar aboard the International Space Station. Backward trajectory analysis estimates the SO2 cloud altitude at 7-12 km. Eulerian model simulations of the SO2 cloud constrained by CATS measurements produced more accurate dispersion patterns compared to those initialized with the back trajectory height estimate. The near-real-time data processing capabilities of CATS are unique, and this work demonstrates the use of these observations to monitor and model volcanic clouds.

  13. The influence of Mn species on the SO2 removal of Mn-based activated carbon catalysts

    International Nuclear Information System (INIS)

    Qu, Yi-Fan; Guo, Jia-Xiu; Chu, Ying-Hao; Sun, Ming-Chao; Yin, Hua-Qiang

    2013-01-01

    Using Mn(NO 3 ) 2 as precursor, a series of Mn-based activated carbon catalysts were prepared by ultrasound-assisted excessive impregnation method and characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and temperature programmed reduction (TPR). The influences of Mn species and nitric acid pretreatment on the removal role of SO 2 were investigated. MnO and Mn 3 O 4 coexist in catalysts calcined at 650 and 800 °C and exhibit best SO 2 removal ability, whereas Mn 2 O 3 formed in the catalyst calcined at 500 °C and shows poor activity. After treatment by nitric acid, the C=O of activated carbon support increases and the crystal size of MnO decreases, resulting in the enhancement of the catalytic activity. During reaction process, manganese oxides are gradually transferred into MnO 2 . And this change directly results in a decrease of activity. But the SO 2 removal rate has been maintained in the range of 30–40%, indicating that MnO 2 still has a certain SO 2 removal ability.

  14. Multi-decadal satellite measurements of passive and eruptive volcanic SO2 emissions

    Science.gov (United States)

    Carn, Simon; Yang, Kai; Krotkov, Nickolay; Prata, Fred; Telling, Jennifer

    2015-04-01

    Periodic injections of sulfur gas species (SO2, H2S) into the stratosphere by volcanic eruptions are among the most important, and yet unpredictable, drivers of natural climate variability. However, passive (lower tropospheric) volcanic degassing is the major component of total volcanic emissions to the atmosphere on a time-averaged basis, but is poorly constrained, impacting estimates of global emissions of other volcanic gases (e.g., CO2). Stratospheric volcanic emissions are very well quantified by satellite remote sensing techniques, and we report ongoing efforts to catalog all significant volcanic SO2 emissions into the stratosphere and troposphere since 1978 using measurements from the ultraviolet (UV) Total Ozone Mapping Spectrometer (TOMS; 1978-2005), Ozone Monitoring Instrument (OMI; 2004 - present) and Ozone Mapping and Profiler Suite (OMPS; 2012 - present) instruments, supplemented by infrared (IR) data from HIRS, MODIS and AIRS. The database, intended for use as a volcanic forcing dataset in climate models, currently includes over 600 eruptions releasing a total of ~100 Tg SO2, with a mean eruption discharge of ~0.2 Tg SO2. Sensitivity to SO2 emissions from smaller eruptions greatly increased following the launch of OMI in 2004, but uncertainties remain on the volcanic flux of other sulfur species other than SO2 (H2S, OCS) due to difficulty of measurement. Although the post-Pinatubo 1991 era is often classified as volcanically quiescent, many smaller eruptions (Volcanic Explosivity Index [VEI] 3-4) since 2000 have injected significant amounts of SO2 into the upper troposphere - lower stratosphere (UTLS), peaking in 2008-2011. We also show how even smaller (VEI 2) tropical eruptions can impact the UTLS and sustain above-background stratospheric aerosol optical depth, thus playing a role in climate forcing on short timescales. To better quantify tropospheric volcanic degassing, we use ~10 years of operational SO2 measurements by OMI to identify the

  15. Processing and analysis techniques involving in-vessel material generation

    Science.gov (United States)

    Schabron, John F [Laramie, WY; Rovani, Jr., Joseph F.

    2012-09-25

    In at least one embodiment, the inventive technology relates to in-vessel generation of a material from a solution of interest as part of a processing and/or analysis operation. Preferred embodiments of the in-vessel material generation (e.g., in-vessel solid material generation) include precipitation; in certain embodiments, analysis and/or processing of the solution of interest may include dissolution of the material, perhaps as part of a successive dissolution protocol using solvents of increasing ability to dissolve. Applications include, but are by no means limited to estimation of a coking onset and solution (e.g., oil) fractionating.

  16. Combined treatment of SO2 and high resistivity fly ash using a pulse energized electron reactor

    International Nuclear Information System (INIS)

    Mizuno, A.; Clements, J.S.; Davis, R.H.

    1984-01-01

    The combined removal of SO 2 and high resistivity fly ash has been demonstrated in a pulse energized electron reactor (PEER). The PEER system which was originally developed for the removal of SO 2 utilizes a positive pulse streamer corona discharge in a non-uniform field geometry. In performance tests on SO 2 , more than 90% was removed with an advantageously small power requirement. Combined treatment performance was demonstrated by introducing high resistivity fly ash into the test gas and the PEER is significantly more efficient than a conventional electrostatic precipitator operated with a dc voltage. Observations show that the PEER agglomerates the fly ash and further that the SO 2 removal efficiency is improved by the presence of fly ash. The electrode configuration and performance results make retrofit consideration attractive

  17. A radiation-electric-field combination principle for SO2-oxidation in Ar-mixtures

    International Nuclear Information System (INIS)

    Leonhardt, J.; Krueger, H.; Popp, P.; Boes, J.

    1981-01-01

    A simple model for a radiation-induced SO 2 -oxidation in Ar using SO 2 /O 2 /Ar-mixtures has been described by Leonhardt a.o. It is possible to improve the efficiency of the radiation-induced SO 2 -oxidation in such mixtures if the electrons produced by the ionizing radiation are accelerated by means of an electric field. The energy of the field-accelerated electrons must be high enough to form reactive SO 2 radicals but not high enough to ionize the gas mixture. Such an arrangement is described. The connection between the rate of SO 3 -formation and the electric field and the connection between SO 3 -formation and decreasing of the O 2 -concentration in the reaction chaimber were experimentally determined. Further the G-values attained by means of the radiation-electric-field combination are discussed. (author)

  18. Curvature dependence of single-walled carbon nanotubes for SO2 adsorption and oxidation

    Science.gov (United States)

    Chen, Yanqiu; Yin, Shi; Li, Yueli; Cen, Wanglai; Li, Jianjun; Yin, Huaqiang

    2017-05-01

    Porous carbon-based catalysts showing high catalytic activity for SO2 oxidation to SO3 is often used in flue gas desulfurization. Their catalytic activity has been ascribed in many publications to the microporous structure and the effect of its spatial confinement. First principles method was used to investigate the adsorption and oxidation of SO2 on the inner and outer surface of single-walled carbon nanotubes (SWCNTs) with different diameters. It is interesting to found that there is a direct correlation: the barrier for the oxidation O_SWCNT + SO2 → SO3 + SWCNT monotonically decreases with the increase of SWCNTs' curvature. The oxygen functional located at the inner wall of SWCNTs with small radius is of higher activity for SO2 oxidation, which is extra enhanced by the spatial confinement effects of SWCNTs. These findings can be useful for the development of carbon-based catalysts and provide clues for the optimization and design of porous carbon catalysts.

  19. US EPA Nonattainment Areas and Designations-SO2 (2010 NAAQS)

    Data.gov (United States)

    U.S. Environmental Protection Agency — This web service contains the following layer: SO2 2010 NAAQS State Level. Full FGDC metadata records for each layer may be found by clicking the layer name at the...

  20. NOx, N2O and SO2 emissions from pressurized fluidized bed combustion

    International Nuclear Information System (INIS)

    Korpela, T.; Lu, Y.

    1996-01-01

    This project continues the analysis of available data from the experimental work at the Otaniemi PFBC test rig using various solid fuels. The study concentrates on the emission and control of NO x N 2 O, and SO 2 under pressurized conditions. The aim of the study is to prepare the database from the available data and make empirical correlations for estimating nitrogen oxide emissions and sulfur capture from PFBC as a function of significant operating parameters and fuel properties. As the first generation of an empirical model, multiple linear regression was developed for predicting NO x , N 2 O and SO 2 emissions from PFBC. These correlations may facilitate preliminary FBC design by estimating NO x , N 2 O and SO 2 emissions. On the basis of statistical inference, the operating conditions employed and the fuel properties selected in the correlations may lend insight into the mechanisms of the formation and destruction of NO x , N 2 O and SO 2 . (author)

  1. Improving industrial designers work process by involving user research

    DEFF Research Database (Denmark)

    Dai, Zheng; Ómarsson, Ólafur

    2011-01-01

    With changing times, new technologies and more opinionated consumers, the modern industrial designer has found himself in need of fresher and more up to date approaches in his daily work. In a fast moving industry, the designer needs to keep a thinking process of dynamic and subjective attitude...... will give the grounding for believing that the industrial designer needs to adopt user research methods to a level where he can still continue to work under the very nature of industrial design that has made it a successful practice for the last century. The combing of the approaches and attitude will help....... User research is part of user centered design (UCD). UCD has a reputation for subjective and reflective practice. In this paper there are two example cases. One is conducted by a classical industrial design process, and another is costing half of energy and time in user research. These examples...

  2. A quasi-classical study of energy transfer in collisions of hyperthermal H atoms with SO2 molecules.

    Science.gov (United States)

    da Silva, Ramon S; Garrido, Juan D; Ballester, Maikel Y

    2017-08-28

    A deep understanding of energy transfer processes in molecular collisions is at central attention in physical chemistry. Particularly vibrational excitation of small molecules colliding with hot light atoms, via a metastable complex formation, has shown to be an efficient manner of enhancing reactivity. A quasi-classical trajectory study of translation-to-vibration energy transfer (T-V ET) in collisions of hyperthermal H( 2 S) atoms with SO 2 (X̃ 1 A ' ) molecules is presented here. For such a study, a double many-body expansion potential energy surface previously reported for HSO 2 ( 2 A) is used. This work was motivated by recent experiments by Ma et al. studying collisions of H + SO 2 at the translational energy of 59 kcal/mol [J. Ma et al., Phys. Rev. A 93, 040702 (2016)]. Calculations reproduce the experimental evidence that during majority of inelastic non-reactive collision processes, there is a metastable intermediate formation (HOSO or HSO 2 ). Nevertheless, the analysis of the trajectories shows that there are two distinct mechanisms in the T-V ET process: direct and indirect. Direct T-V processes are responsible for the high population of SO 2 with relatively low vibrational excitation energy, while indirect ones dominate the conversion from translational energy to high values of the vibrational counterpart.

  3. Physical Processes Involved In Yellow Sea Solitary Waves

    Science.gov (United States)

    Warn-Varnas, A.; Chin-Bing, S.; King, D.; Lamb, K.; Hawkins, J.; Teixeira, M.

    The study area is located south of the Shandong peninsula. In this area, soliton gener- ation and propagation studies are per formed with the Lamb(1994) model. The model is nonhydrostatic and is formulated in 2 1/2 dimensions for terrain following c oordi- nates. In the area, 20 to 30 m topographic variations over distances of 10 to 20 km are found to occur in the digit al atlas of Choi (1999). The area is shallow with maximum depths ranging from 40 m to 70 m. Along the southern boundary of the region the semi-diurnal tidal strength magnitude varies from .6 m/sec to 1.2 m/sec, Fang(1994). We show that, for sum mer conditions, the existing physical processes associated with the semi-diurnal tidal flow over the topographic variations , in the shelfbreak region, lead to the formation of internal bores in the model simulations. Through acting phys- ical proce sses, the internal bores propagate on and off the shelf. A disintegration process of internal bores into solitary waves occ urs through frequency and ampli- tude dispersion. SAR observations of the area show images containing six events con- sisting of internal bores and solitary waves that travel in a well-defined direction for two and a half days. The origin of the trains appeared to be at a point along a steep topo graphic drop. The SAR observations are used for guiding and tuning the model simulations, by comparing spectra of observed and modeled wavelengths. The tuned model yields wavelengths that are within a factor of 2 of the SAR data. The modeled amp litudes are within a factor of 2 of amplitudes obtained with a two-layer model and the SAR data The signature on the acoustical field of ongoing physical processes through the interaction of the resultant oceanic struct ure with the acoustical field is pursued. Internal bore and solitary wave structures interact with the acoustic field. A re distribution of acoustical energy to higher acoustical modes occurs at some fre- quencies. Mode decomposition of the

  4. Physiological responses of Norway spruce trees to elevated CO2 and SO2

    NARCIS (Netherlands)

    Tausz, M.; De Kok, L.J.; Stulen, I.

    Young Norway spruce (Picea abies (L.) Karst.) trees were exposed to elevated CO2 (0.8 mL L(-1)), SO2 (0.06 mu L L(-1)), and elevated CO2 and SO2 (0.8 mL L(-1) and 0.06 mu L L(-1), respectively) for three months. Exposure to elevated CO2 resulted in an increased biomass production of the needles,

  5. Carbon-enriched coal fly ash as a precursor of activated carbons for SO2 removal.

    Science.gov (United States)

    Izquierdo, M T; Rubio, B

    2008-06-30

    Carbon-enriched coal fly ash was evaluated in this work as a low-cost adsorbent for SO2 removal from stack gases. The unburned carbon in coal fly ash was concentrated by mechanical sieving and vegetal oil agglomeration. The carbon concentrates were activated with steam at 900 degrees C in order to develop porosity onto the samples. The performance of these samples in the SO2 abatement was tested in the following conditions: 100 degrees C, 1000 ppmv SO2, 5% O2, 6% water vapor. A good SO2 removal capacity was shown by some of the studied samples that can be related to their textural properties. Cycles of SO2 adsorption/regeneration were carried out in order to evaluate the possibility of thermal regeneration and re-use of these carbons. Regeneration of the exhausted carbons was carried out at 400 degrees C of temperature and a flow of 25 ml/min of Ar. After each cycle, the SO2 removal capacity of the sample decreases.

  6. Optimization of alternative options for SO2 emissions control in the Mexican electrical sector

    International Nuclear Information System (INIS)

    Islas, Jorge; Grande, Genice

    2007-01-01

    This article develops a least-cost optimization model in terms of the projected SO 2 abatement costs of nine selected options for SO 2 emissions control in the 10 most polluting power plants of the Mexican electrical sector (MES)-including SO 2 scrubbing technologies, fuel oil hydrotreating desulphurization and fuel substitutions. The model not only finds the optimal combination of SO 2 control options and generating units at 10% reduction intervals referred to the total SO 2 emissions but also meets the restriction imposed in the NOM-085-ECOL-1994 (Mexican Official Norm) for allowable emission levels within critical zones. Similarly, two schemes are studied and analysed in this model: the first case considers the economical benefits derived from the substitution of fuel oil by imported low sulphur content coal in the Petacalco power plant and; the second case does not considered such economical benefits. Finally, results are obtained for these two cases in terms of the corresponding costs-investment, O and M, fuel-, abatement costs and the SO 2 emissions reduction

  7. Experimental studies on the simultaneous reduction of NO and SO2 emissions by re burning

    International Nuclear Information System (INIS)

    Sun, Rui; Yu, Leibo; Fei, Jun; Mu, Yangyang; Zhang, Xin; Sun, Shaozeng; Wu, Shaohua

    2010-01-01

    The simultaneous reduction of NO and SO 2 by pulverized coal re burning was studied in a drop tube furnace (DTF). A bituminous pulverized coal was chosen as the re burning fuel, and calcium oxide was added as desulfurizer. The influences of stoichiometric ratio (SR), re burning temperature, calcium to sulfur ratio (Ca/ S), and residence time on efficiency of removing NO and SO 2 were studied by DTF hot experiments. The experiment results showed that, at the condition of the re burning temperature 1200 degree Celsius, Ca/ S=1.5, NO reduction efficiency decreased with the increase of re burning fuels stoichiometric ratio, but SO 2 reduction efficiency increased. When the re burning temperature increased from 1000 degree Celsius to 1200 degree Celsius, NO and SO 2 reduction efficiencies initially increased, but then decreased as temperature higher than 1100 degree Celsius. NO reduction efficiency decreased when Ca/ S changed from 1.0 to 2.5, and SO 2 reduction efficiency increased at all times, in spite of the increasing trend became flat when Ca/ S was higher than 2.0. Among all tests, high SO 2 and NO reduction ratios were obtained at SR of 0.8∼0.9 and Ca/ S of 1.5. The mechanisms of desulfurization and denitrification are also discussed and presented to explain the reactions routine in the DTF. (author)

  8. Nitrile-functionalized tertiary amines as highly efficient and reversible SO2 absorbents

    International Nuclear Information System (INIS)

    Hong, Sung Yun; Kim, Heehwan; Kim, Young Jin; Jeong, Junkyo; Cheong, Minserk; Lee, Hyunjoo; Kim, Hoon Sik; Lee, Je Seung

    2014-01-01

    Highlights: • Nitrile-functionalized tertiary amines physically and reversibly absorb SO 2 . • Tertiary alkanolamines chemically and irreversibly absorb SO 2 through OH group. • SO 2 absorption modes were studied by spectroscopy and computational calculations. -- Abstract: Three different types of nitrile-functionalized amines, including 3-(N,N-diethylamino)propionitrile (DEAPN), 3-(N,N-dibutylamino)propionitrile (DBAPN), and N-methyl-N,N-dipropionitrile amine (MADPN) were synthesized, and their SO 2 absorption performances were evaluated and compared with those of hydroxy-functionalized amines such as N,N-diethyl-N-ethanol amine (DEEA), N,N-dibutyl-N-ethanol amine (DBEA), and N-methyl-N,N-diethanol amine (MDEA). Absorption–desorption cycle experiments clearly demonstrate that the nitrile-functionalized amines are more efficient than the hydroxy-functionalized amines in terms of absorption rate and regenerability. Computational calculations with DBEA and DBAPN revealed that DBEA bearing a hydroxyethyl group chemically interacts with SO 2 through oxygen atom, forming an ionic compound with a covalently bound -OSO 2 − group. On the contrary, DBAPN bearing a nitrile group physically interacts with SO 2 through the nitrogen and the hydrogen atoms of the two methylene groups adjacent to the amino and nitrile functionalities

  9. Emission spectrum and relaxation kinetics of SO2 induced by 266 nm laser.

    Science.gov (United States)

    Zhang, Guiyin; Zhang, Lianshui; Jin, Yidong

    2010-09-15

    Laser induced fluorescence (LIF) emission spectrum of SO(2) in the range of 270.0-470.0 nm has been obtained with the quadruple harmonic output (266 nm) of a pulsed Nd:YAG laser as excitation source. The spectrum is composed of a continuous envelope in the short wavelength side, while it shows the character of banded structure superimposed on a continuous one in the long wavelength region. Fluorescence emission from the hybrid states of A(1)A(2)+B(1)B(1) and X(1)A(1)+B(1)B(1) forms the continuous envelope and phosphorescence emission from the triplet state a(3)B(1) forms the banded progression. It is also found that direct emission from laser excited states is very weak. The primary portion of the emission is from the energy levels populated by collision relaxation or collision induced intersystem crossing process. The harmonic frequencies and inharmonic coefficients of the symmetric stretching vibration and the bending vibration of X(1)A(1) state are derived from the ascription of the phosphorescence progression. Copyright 2010 Elsevier B.V. All rights reserved.

  10. An analysis of SO2 emission compliance under the 1990 Clean Air Act Amendments

    International Nuclear Information System (INIS)

    Hanson, D.A.; Cilek, C.M.; Pandola, G.; Taxon, T.

    1992-01-01

    The effectiveness of SO 2 emission allowance trading under Title 4 of the 1990 Amendments to the Clean Air Act (CAA) is of great interest due to the innovative nature of this market incentive approach. However, it may be a mistake to frame the compliance problem for a utility as a decision to trade or not. Trading of allowances should be the consequence, not the decision. The two meaningful decision variables for a utility are the control approaches chosen for its units and the amount of allowances to hold in its portfolio of assets for the future. The number allowances to be bought or sold (i.e. traded) is determined by the emission reduction and banking decisions. Our preferred approach is to think of the problem in terms of ABC's of the 1990 CAA Amendments: abatement strategy, banking, and cost competitiveness. The implications of the general principles presented in this paper on least cost emission reductions and emissions banking to hedge against risk are being simulated with version 2 of the ARGUS model representing the electric utility sector and regional coal supplies and transportation rates. A rational expectations forecast for allowances prices is being computed. The computed allowance price path has the property that demand for allowances by electric utilities for current use or for banking must equal the supply of allowances issued by the federal government or provided as forward market contracts in private market transactions involving non-utility speculators. From this rational expectations equilibrium forecast, uncertainties are being explored using sensitivity tests. Some of the key issues are the amount of scrubbing and when it is economical to install it, the amount of coal switching and how much low sulfur coal premiums will be bid up; and the amount of emission trading within utilities and among different utilities

  11. A new method research of monitoring low concentration NO and SO2 mixed gas

    Science.gov (United States)

    Bo, Peng; Gao, Chao; Guo, Yongcai; Chen, Fang

    2018-01-01

    In order to reduce the pollution of the environment, China has implemented a new ultra-low emission control regulations for polluting gas, requiring new coal-fired power plant emissions SO2 less than 30ppm, NO less than 75ppm, NO2 less than 50ppm, Monitoring low concentration of NO and SO2 mixed gases , DOAS technology facing new challenges, SO2 absorb significantly weaken at the original absorption peak, what more the SNR is very low, it is difficult to extract the characteristic signal, and thus cannot obtain its concentration. So it cannot separate the signal of NO from the mixed gas at the wavelength of 200 230nm through the law of spectral superposition, it cannot calculate the concentration of NO. The classical DOAS technology cannot meet the needs of monitoring. In this paper, we found another absorption spectrum segment of SO2, the SNR is 10 times higher than before, Will not be affected by NO, can calculate the concentration of SO2 accurately, A new method of segmentation and demagnetization separation technology of spectral signals is proposed, which achieves the monitoring the low concentration mixed gas accurately. This function cannot be achieved by the classical DOAS. Detection limit of this method is 0.1ppm per meter which is higher than before, The relative error below 5% when the concentration between 0 5ppm, the concentration of NO between 6 75ppm and SO2 between 6 30ppm the relative error below 1.5%, it has made a great breakthrough In the low concentration of NO and SO2 monitoring. It has great scientific significance and reference value for the development of coal-fired power plant emission control, atmospheric environmental monitoring and high-precision on-line instrumentation.

  12. Applying UV cameras for SO2 detection to distant or optically thick volcanic plumes

    Science.gov (United States)

    Kern, Christoph; Werner, Cynthia; Elias, Tamar; Sutton, A. Jeff; Lübcke, Peter

    2013-01-01

    Ultraviolet (UV) camera systems represent an exciting new technology for measuring two dimensional sulfur dioxide (SO2) distributions in volcanic plumes. The high frame rate of the cameras allows the retrieval of SO2 emission rates at time scales of 1 Hz or higher, thus allowing the investigation of high-frequency signals and making integrated and comparative studies with other high-data-rate volcano monitoring techniques possible. One drawback of the technique, however, is the limited spectral information recorded by the imaging systems. Here, a framework for simulating the sensitivity of UV cameras to various SO2 distributions is introduced. Both the wavelength-dependent transmittance of the optical imaging system and the radiative transfer in the atmosphere are modeled. The framework is then applied to study the behavior of different optical setups and used to simulate the response of these instruments to volcanic plumes containing varying SO2 and aerosol abundances located at various distances from the sensor. Results show that UV radiative transfer in and around distant and/or optically thick plumes typically leads to a lower sensitivity to SO2 than expected when assuming a standard Beer–Lambert absorption model. Furthermore, camera response is often non-linear in SO2 and dependent on distance to the plume and plume aerosol optical thickness and single scatter albedo. The model results are compared with camera measurements made at Kilauea Volcano (Hawaii) and a method for integrating moderate resolution differential optical absorption spectroscopy data with UV imagery to retrieve improved SO2 column densities is discussed.

  13. η2-SO2 Linkage Photoisomer of an Osmium Coordination Complex.

    Science.gov (United States)

    Cole, Jacqueline M; Velazquez-Garcia, Jose de J; Gosztola, David J; Wang, SuYin Grass; Chen, Yu-Sheng

    2018-03-05

    We report the discovery of an η 2 -SO 2 linkage photoisomer in the osmium pentaammine coordination complex, [Os(NH 3 ) 5 (SO 2 )][Os(NH 3 ) 5 (HSO 3 )]Cl 4 (1). Its dark- and light-induced crystal structures are determined via synchrotron X-ray crystallography, at 100 K, where the photoinduced state is metastable in a single crystal that has been stimulated by 505 nm light for 2.5 h. The SO 2 photoisomer in the [Os(NH 3 ) 5 (SO 2 )] 2+ cation contrasts starkly with the photoinactivity of the HSO 3 ligand in its companion [Os(NH 3 ) 5 (HSO 3 )] + cation within the crystallographic asymmetric unit of this single crystal. Panchromatic optical absorption characteristics of this single crystal are revealed in both dark- and light-induced states, using concerted absorption spectroscopy and optical microscopy. Its absorption halves across most of its visible spectrum, upon exposure to 505 nm light. The SO 2 ligand seems to be responsible for this photoinduced bleaching effect, judging from a comparison of the dark- and light-induced crystal structures of 1. The SO 2 photoisomerism is found to be thermally reversible, and so 1 presents a rare example of an osmium-based solid-state optical switch. Such switching in an osmium complex is significant because bottom-row transition metals stand to offer linkage photoisomerism with the greatest photoconversion levels and thermal stability. The demonstration of η 2 -SO 2 bonding in this complex also represents a fundamental contribution to osmium coordination chemistry.

  14. Laboratory study of SO2 dry deposition on limestone and marble: Effects of humidity and surface variables

    Science.gov (United States)

    Spiker, E. C.; Hosker, R.P.; Weintraub, V.C.; Sherwood, S.I.

    1995-01-01

    The dry deposition of gaseous air pollutants on stone and other materials is influenced by atmospheric processes and the chemical characteristics of the deposited gas species and of the specific receptor material. Previous studies have shown that relative humidity, surface moisture, and acid buffering capability of the receptor surface are very important factors. To better quantify this behavior, a special recirculating wind tunnel/environmental chamber was constructed, in which wind speed, turbulence, air temperature, relative humidity, and concentrations of several pollutants (SO2, O3, nitrogen oxides) can be held constant. An airfoil sample holder holds up to eight stone samples (3.8 cm in diameter and 1 cm thick) in nearly identical exposure conditions. SO2 deposition on limestone was found to increase exponentially with increasing relative humidity (RH). Marble behaves similarly, but with a much lower deposition rate. Trends indicate there is little deposition below 20% RH on clean limestone and below 60% RH on clean marble. This large difference is due to the limestone's greater porosity, surface roughness, and effective surface area. These results indicate surface variables generally limit SO2 deposition below about 70% RH on limestone and below at least 95% RH on marble. Aerodynamic variables generally limit deposition at higher relative humidity or when the surface is wet.The dry deposition of gaseous air pollutants on stone and other materials is influenced by atmospheric processes and the chemical characteristics of the deposited gas species and of the specific receptor material. Previous studies have shown that relative humidity, surface moisture, and acid buffering capability of the receptor surface are very important factors. To better quantify this behavior, a special recirculating wind tunnel/environmental chamber was constructed, in which wind speed, turbulence, air temperature, relative humidity, and concentrations of several pollutants (SO2, O3

  15. Formation of secondary aerosols from gasoline vehicle exhaust when mixing with SO2

    Directory of Open Access Journals (Sweden)

    T. Liu

    2016-01-01

    Full Text Available Sulfur dioxide (SO2 can enhance the formation of secondary aerosols from biogenic volatile organic compounds (VOCs, but its influence on secondary aerosol formation from anthropogenic VOCs, particularly complex mixtures like vehicle exhaust, remains uncertain. Gasoline vehicle exhaust (GVE and SO2, a typical pollutant from coal burning, are directly co-introduced into a smog chamber, in this study, to investigate the formation of secondary organic aerosols (SOA and sulfate aerosols through photooxidation. New particle formation was enhanced, while substantial sulfate was formed through the oxidation of SO2 in the presence of high concentration of SO2. Homogenous oxidation by OH radicals contributed a negligible fraction to the conversion of SO2 to sulfate, and instead the oxidation by stabilized Criegee intermediates (sCIs, formed from alkenes in the exhaust reacting with ozone, dominated the conversion of SO2. After 5 h of photochemical aging, GVE's SOA production factor revealed an increase by 60–200 % in the presence of high concentration of SO2. The increase could principally be attributed to acid-catalyzed SOA formation as evidenced by the strong positive linear correlation (R2 = 0.97 between the SOA production factor and in situ particle acidity calculated by the AIM-II model. A high-resolution time-of-flight aerosol mass spectrometer (HR-TOF-AMS resolved OA's relatively lower oxygen-to-carbon (O : C (0.44 ± 0.02 and higher hydrogen-to-carbon (H : C (1.40 ± 0.03 molar ratios for the GVE / SO2 mixture, with a significantly lower estimated average carbon oxidation state (OSc of −0.51 ± 0.06 than −0.19 ± 0.08 for GVE alone. The relative higher mass loading of OA in the experiments with SO2 might be a significant explanation for the lower SOA oxidation degree.

  16. Partial discharge early-warning through ultraviolet spectroscopic detection of SO2

    International Nuclear Information System (INIS)

    Zhao, Yu; Wang, Xianpei; Dai, Dangdang; Dong, Zhengcheng; Huang, Yunguang

    2014-01-01

    Surveillance of SF 6  decomposition products is significant for detection of partial discharge (PD) in gas insulation switchgear (GIS). As a basis in on-site detection and diagnosis, PD early-warning aims to quickly find the abnormalities using a simple and cheap device. In this paper, SO 2  is chosen as a feature product and detected through ultraviolet spectroscopy. The derivative method is employed for baseline correction and spectral enhancement. The standard gases of the main decomposition products are qualitatively and quantitatively detected. Then decomposition experiments with different defects are designed to further verify the feasibility. As a stable decomposition product under PD, SO 2  is proved to be applicable for PD early-warning in the field. By selecting the appropriate wavelength range, namely 290–310 nm, ultraviolet derivative spectroscopy is sensitive enough to the trace SO 2  in the decomposed gas and the interference of other products can be avoided. Fast Fourier transform could be used for feature extraction in qualitative detection. Concentrations of SO 2  and other by-products increase with increasing discharge time and could be affected by the discharge energy and PD type. Ultraviolet detection based on SO 2  is effective for PD early-warning but the threshold should still be carefully selected in practice. (paper)

  17. Attenuated Mycobacterium tuberculosis SO2 vaccine candidate is unable to induce cell death.

    Directory of Open Access Journals (Sweden)

    Adriana Aporta

    Full Text Available It has been proposed that Mycobacterium tuberculosis virulent strains inhibit apoptosis and trigger cell death by necrosis of host macrophages to evade innate immunity, while non-virulent strains induce typical apoptosis activating a protective host response. As part of the characterization of a novel tuberculosis vaccine candidate, the M. tuberculosis phoP mutant SO2, we sought to evaluate its potential to induce host cell death. The parental M. tuberculosis MT103 strain and the current vaccine against tuberculosis Bacillus Calmette-Guérin (BCG were used as comparators in mouse models in vitro and in vivo. Our data reveal that attenuated SO2 was unable to induce apoptotic events neither in mouse macrophages in vitro nor during lung infection in vivo. In contrast, virulent MT103 triggers typical apoptotic events with phosphatidylserine exposure, caspase-3 activation and nuclear condensation and fragmentation. BCG strain behaved like SO2 and did not induce apoptosis. A clonogenic survival assay confirmed that viability of BCG- or SO2-infected macrophages was unaffected. Our results discard apoptosis as the protective mechanism induced by SO2 vaccine and provide evidence for positive correlation between classical apoptosis induction and virulent strains, suggesting apoptosis as a possible virulence determinant during M. tuberculosis infection.

  18. A density functional theory insight towards the rational design of ionic liquids for SO2 capture.

    Science.gov (United States)

    García, Gregorio; Atilhan, Mert; Aparicio, Santiago

    2015-05-28

    A systematic density functional theory (DFT) analysis has been carried out to obtain information at the molecular level on the key parameters related to efficient SO2 capture by ionic liquids (ILs). A set of 55 ILs, for which high gas solubility is expected, has been selected. SO2 solubility of ILs was firstly predicted based on the COSMO-RS (Conductor-like Screening Model for Real Solvents) method, which provides a good prediction of gas solubility data in ILs without prior experimental knowledge of the compounds' features. Then, interactions between SO2 and ILs were deeply analyzed through DFT simulations. This work provides valuable information about required factors at the molecular level to provide high SO2 solubility in ILs, which is crucial for further implementation of these materials in the future. In our opinion, systematic research on ILs for SO2 capture increases our knowledge about those factors which could be controlled at the molecular level, providing an approach for the rational design of task-specific ILs.

  19. Preliminary performance and operating results from the integrated dry NOx/SO2 emissions control system

    International Nuclear Information System (INIS)

    Hunt, T.; Schott, G.; Smith, R.; Muzio, L.; Jones, D.; Mali E.; Arrigoni, T.

    1993-01-01

    The Integrated Dry NO x /SO 2 Emissions Control System was installed at Public Service Company of Colorado's Arapaho 4 generating station in 1992 in cooperation with the U.S. Department of Energy (DOE) and and the Electric Power Research Institute (EPRI). This full scale 100 MWe demonstration combines low-NO x burners, overfire air, and selective noncatalytic reduction (SNCR) for NO x control and dry sorbent injection with humidification for SO 2 control. Operation and testing of the Integrated Dry NO x /SO 2 Emissions Control System began in August 1992 and will continue through mid 1994. Preliminary results of the NO x control technologies show that the original system goal of 70% NO x removal has been easily met and that NO x removals of up to 80% are possible at full load with the combustion and SNCR systems. Testing of the dry sorbent injection system with low sulfur coal began in April 1993 using a calcium-based reagent. A maximum SO 2 removal of 40% has been achieved with duct injection of commercial calcium hydroxide and humidification to a 25 degrees F approach to saturation. Sodium-based dry sorbent injection is expected to achieved up to a 70% SO 2 reduction

  20. Mechanical stretching stimulates collagen synthesis via down-regulating SO2/AAT1 pathway

    Science.gov (United States)

    Liu, Jia; Yu, Wen; Liu, Yan; Chen, Selena; Huang, Yaqian; Li, Xiaohui; Liu, Cuiping; Zhang, Yanqiu; Li, Zhenzhen; Du, Jie; Tang, Chaoshu; Du, Junbao; Jin, Hongfang

    2016-01-01

    The aim of the study was to investigate the role of endogenous sulfur dioxide (SO2)/ aspartate aminotransferase 1 (AAT1) pathway in stretch-induced excessive collagen expression and its mechanism. The mechanical stretch downregulated SO2/AAT1 pathway and increased collagen I and III protein expression. Importantly, AAT1 overexpression blocked the increase in collagen I and III expression, transforming growth factor-β1 (TGF- β1) expression and phosphorylation of Smad2/3 induced by stretch, but AAT1 knockdown mimicked the increase in collagen I and III expression, TGF- β1 expression and phosphorylation of Smad2/3 induced by stretch. Mechanistically, SB431542, a TGF-β1/Smad2/3 inhibitor, eliminated excessive collagen I and III accumulation induced by AAT1 knockdown, stretch or stretch plus AAT1 knockdown. In a rat model of high pulmonary blood flow-induced pulmonary vascular collagen accumulation, AAT1 expression and SO2 content in lung tissues of rat were reduced in shunt rats with high pulmonary blood flow. Supplement of SO2 derivatives inhibited activation of TGF- β1/Smad2/3 pathway and alleviated the excessive collagen accumulation in lung tissues of shunt rats. The results suggested that deficiency of endogenous SO2/AAT1 pathway mediated mechanical stretch-stimulated abnormal collagen accumulation via TGF-β1/Smad2/3 pathway. PMID:26880260

  1. Photoacoustic imaging to assess pixel-based sO2 distributions in experimental prostate tumors.

    Science.gov (United States)

    Bendinger, Alina L; Glowa, Christin; Peter, Jörg; Karger, Christian P

    2018-03-01

    A protocol for photoacoustic imaging (PAI) has been developed to assess pixel-based oxygen saturation (sO2) distributions of experimental tumor models. The protocol was applied to evaluate the dependence of PAI results on measurement settings, reproducibility of PAI, and for the characterization of the oxygenation status of experimental prostate tumor sublines (Dunning R3327-H, -HI, -AT1) implanted subcutaneously in male Copenhagen rats. The three-dimensional (3-D) PA data employing two wavelengths were used to estimate sO2 distributions. If the PA signal was sufficiently strong, the distributions were independent from signal gain, threshold, and positioning of animals. Reproducibility of sO2 distributions with respect to shape and median values was demonstrated over several days. The three tumor sublines were characterized by the shapes of their sO2 distributions and their temporal response after external changes of the oxygen supply (100% O2 or air breathing and clamping of tumor-supplying artery). The established protocol showed to be suitable for detecting temporal changes in tumor oxygenation as well as differences in oxygenation between tumor sublines. PA results were in accordance with histology for hypoxia, perfusion, and vasculature. The presented protocol for the assessment of pixel-based sO2 distributions provides more detailed information as compared to conventional region-of-interest-based analysis of PAI, especially with respect to the detection of temporal changes and tumor heterogeneity. (2018) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE).

  2. SO2 absorption in EmimCl-TEG deep eutectic solvents.

    Science.gov (United States)

    Yang, Dezhong; Zhang, Shaoze; Jiang, De-En; Dai, Sheng

    2018-05-23

    Deep eutectic solvents (DESs) based on 1-ethyl-3-methylimidazolium chloride (EmimCl) and triethylene glycol (TEG) with different molar ratios (from 6 : 1 to 1 : 1) were prepared. FTIR and theoretical calculation indicated that the C2-H on the imidazolium ring form hydrogen bonds with the hydroxyl group rather than the ether O atom of the TEG. The EmimCl-TEG DESs can efficiently capture SO2; in particular, EmimCl-TEG (6 : 1) can capture 0.54 g SO2 per gram of solvent at 0.10 atm and 20 °C, the highest absorption amount for DESs under the same conditions. Theoretical calculation showed that the high SO2 absorption capacity was mainly due to the strong charge-transfer interaction between SO2 and the anion Cl-. Moreover, SO2 desorption in the DESs can be controlled by tuning the interaction between EmimCl and TEG, and the DESs can be cycled many times.

  3. Photoacoustic imaging to assess pixel-based sO2 distributions in experimental prostate tumors

    Science.gov (United States)

    Bendinger, Alina L.; Glowa, Christin; Peter, Jörg; Karger, Christian P.

    2018-03-01

    A protocol for photoacoustic imaging (PAI) has been developed to assess pixel-based oxygen saturation (sO2) distributions of experimental tumor models. The protocol was applied to evaluate the dependence of PAI results on measurement settings, reproducibility of PAI, and for the characterization of the oxygenation status of experimental prostate tumor sublines (Dunning R3327-H, -HI, -AT1) implanted subcutaneously in male Copenhagen rats. The three-dimensional (3-D) PA data employing two wavelengths were used to estimate sO2 distributions. If the PA signal was sufficiently strong, the distributions were independent from signal gain, threshold, and positioning of animals. Reproducibility of sO2 distributions with respect to shape and median values was demonstrated over several days. The three tumor sublines were characterized by the shapes of their sO2 distributions and their temporal response after external changes of the oxygen supply (100% O2 or air breathing and clamping of tumor-supplying artery). The established protocol showed to be suitable for detecting temporal changes in tumor oxygenation as well as differences in oxygenation between tumor sublines. PA results were in accordance with histology for hypoxia, perfusion, and vasculature. The presented protocol for the assessment of pixel-based sO2 distributions provides more detailed information as compared to conventional region-of-interest-based analysis of PAI, especially with respect to the detection of temporal changes and tumor heterogeneity.

  4. SO2 pollution of heavy oil-fired steam power plants in Iran

    International Nuclear Information System (INIS)

    Nazari, S.; Shahhoseini, O.; Sohrabi-Kashani, A.; Davari, S.; Sahabi, H.; Rezaeian, A.

    2012-01-01

    Steam power plants using heavy oil provided about 17.4%, equivalent to 35.49 TWh, of electricity in Iran in 2007. However, having 1.55–3.5 weight percentage of sulfur, heavy oil produces SO 2 pollutant. Utilization of Flue Gas Desulfurization systems (FGD) in Iran's steam power plants is not common and thereby, this pollutant is dispersed in the atmosphere easily. In 2007, the average emission factor of SO 2 pollutant for steam power plants was 15.27 g/kWh, which means regarding the amount of electricity generated by steam power plants using heavy oil, 541,000 Mg of this pollutant was produced. In this study, mass distribution of SO 2 in terms of Mg/yr is considered and dispersion of this pollutant in each of the 16 steam power plants under study is modeled using Atmospheric Dispersion Modeling System (ADMS). Details of this study are demonstrated using Geographical Information System (GIS) software, ArcGIS. Finally, the average emission factor of SO 2 and the emission of it in Iran's steam power plants as well as SO 2 emission reduction programs of this country are compared with their alternatives in Turkey and China.

  5. Dissociative phototionization cross sections of H2, SO2 and H2O

    International Nuclear Information System (INIS)

    Chung, Y.

    1989-01-01

    The partial photoionization cross sections of H 2 , SO 2 , and H 2 O were calculated from the measured photoionization branching ratios and the known total photoionization cross sections. The branching ratios were measured with a time-of-flight mass spectrometer and synchrotron radiation. The branching ratios Of H 2 , SO 2 , and H 2 O were measured for 100 ∼ 410, 150 ∼ 380 and 120 ∼ 720 angstrom. The author also measured the photoionization yield Of SO 2 from 520 to 665 angstrom using a double ion chamber and a glow discharge light source. The principle of a time-of-flight mass spectrometer is explained. New calculations were made to see how the design of the mass spectrometer, applied voltage, and kinetic energy of the ions affect the overall performance of the mass spectrometer. Several useful techniques that we used at the synchrotron for wavelength calibration and higher order suppression are also discussed

  6. Removal of NO and SO2 in Corona Discharge Plasma Reactor with Water Film

    Institute of Scientific and Technical Information of China (English)

    贺元吉; 董丽敏; 杨嘉祥

    2004-01-01

    In this paper, a novel type of a corona discharge plasma reactor was designed, which consists of needle-plate-combined electrodes, in which a series of needle electrodes are placed in a glass container filled with flue gas, and a plate electrode is immersed in the water. Based on this model, the removal of NO and SO2 was tested experimentally. In addition, the effect of streamer polarity on the reduction of SO2 and NO was investigated in detail. The experimental results show that the corona wind formed between the high-voltage needle electrode and the water by corona discharge enhances the cleaning efficiency of the flue gas because of the presence of water,and the cleaning efficiency will increase with the increase of applied dc voltage within a definite range. The removal efficiency of SO2 up to 98%, and about 85% of NOx removal under suitable conditions is obtained in our experiments.

  7. Kinetics of a Criegee intermediate that would survive high humidity and may oxidize atmospheric SO2.

    Science.gov (United States)

    Huang, Hao-Li; Chao, Wen; Lin, Jim Jr-Min

    2015-09-01

    Criegee intermediates are thought to play a role in atmospheric chemistry, in particular, the oxidation of SO2, which produces SO3 and subsequently H2SO4, an important constituent of aerosols and acid rain. However, the impact of such oxidation reactions is affected by the reactions of Criegee intermediates with water vapor, because of high water concentrations in the troposphere. In this work, the kinetics of the reactions of dimethyl substituted Criegee intermediate (CH3)2COO with water vapor and with SO2 were directly measured via UV absorption of (CH3)2COO under near-atmospheric conditions. The results indicate that (i) the water reaction with (CH3)2COO is not fast enough (kH2O SO2 at a near-gas-kinetic-limit rate (kSO2 = 1.3 × 10(-10) cm(3) s(-1)). These observations imply a significant fraction of atmospheric (CH3)2COO may survive under humid conditions and react with SO2, very different from the case of the simplest Criegee intermediate CH2OO, in which the reaction with water dimer predominates in the CH2OO decay under typical tropospheric conditions. In addition, a significant pressure dependence was observed for the reaction of (CH3)2COO with SO2, suggesting the use of low pressure rate may underestimate the impact of this reaction. This work demonstrates that the reactivity of a Criegee intermediate toward water vapor strongly depends on its structure, which will influence the main decay pathways and steady-state concentrations for various Criegee intermediates in the atmosphere.

  8. Energy efficient SO2 removal from flue gases using the method Wellman-Lord

    International Nuclear Information System (INIS)

    Dzhonova-Atanasova, D.; Razkazova-Velkova, E.; Ljutzkanov, L.; Kolev, N.; Kolev, D.

    2013-01-01

    Full text: Investigations on development of energy efficient technology for SO 2 removal from flue gases of combustion systems by using the method Wellman-Lord are presented. It is characterized by absorption of sulfur dioxide with sodium sulfite solution, which reacts to form sodium bisulfite. The absorber is a packed column with multiple stages. After evaporation of the solution, SO 2 and sodium sulfite are obtained. The latter is dissolved in water from condensation of the steam carrying SO 2 from the evaporator. The regenerated solution returns in the absorber. The SO 2 removed from the flue gases is obtained as a pure product for use in chemical, food or wine production. The data discussed in the literature sources on flue gas desulfurization demonstrate the predominance of the methods with lime or limestone as absorbent, due to higher capital investments associated with the method of Wellman-Lord. A technological and economical evaluation of this regenerative method is presented in comparison to the non-regenerative gypsum method, using data from the existing sources and our own experience from the development of an innovative gypsum technology. Three solutions are discussed for significant enhancement of the method efficiency on the basis of a considerable increasing of the SO 2 concentration in the saturated absorbent. The improved method uses about 40% less heat for absorbent regeneration, in comparison to the existing applications of the method Wellman-Lord, and gives in addition the possibility to regenerate 95% of the consumed heat for heating water streams to about 90°C. Moreover, the incorporation in the installation of our system with contact economizers of second generation, already in industrial application, enables utilization of the waste heat of the flue gases for district heating. The employment of this system also leads to significant decreasing of the NO x emissions. key words: SO 2 removal, flue gases, absorption

  9. Experimental Study of SO2 Removal by Pulsed DBD Along with the Application of Magnetic Field

    International Nuclear Information System (INIS)

    Rong Mingzhe; Liu Dingxin; Wang Xiaohua; Wang Junhua

    2007-01-01

    Dielectric barrier discharge (DBD) for SO 2 removal from indoor air is investigated. In order to improve the removal efficiency, two novel methods are combined in this paper, namely by applying a pulsed driving voltage with nanosecond rising time and applying a magnetic field. For SO 2 removal efficiency, different matches of electric field and magnetic field are discussed. And nanosecond rising edge pulsed power supply and microsecond rising edge pulsed power supply are compared. It can be concluded that a pulsed DBD with nanosecond rising edge should be adopted, and electrical field and magnetic field should be applied in an appropriate match

  10. Aura OMI observations of regional SO2 and NO2 pollution changes from 2005 to 2015

    Directory of Open Access Journals (Sweden)

    N. A. Krotkov

    2016-04-01

    Full Text Available The Ozone Monitoring Instrument (OMI onboard NASA's Aura satellite has been providing global observations of the ozone layer and key atmospheric pollutant gases, such as nitrogen dioxide (NO2 and sulfur dioxide (SO2, since October 2004. The data products from the same instrument provide consistent spatial and temporal coverage and permit the study of anthropogenic and natural emissions on local-to-global scales. In this paper, we examine changes in SO2 and NO2 over some of the world's most polluted industrialized regions during the first decade of OMI observations. In terms of regional pollution changes, we see both upward and downward trends, sometimes in opposite directions for NO2 and SO2, for different study areas. The trends are, for the most part, associated with economic and/or technological changes in energy use, as well as regional regulatory policies. Over the eastern US, both NO2 and SO2 levels decreased dramatically from 2005 to 2015, by more than 40 and 80 %, respectively, as a result of both technological improvements and stricter regulations of emissions. OMI confirmed large reductions in SO2 over eastern Europe's largest coal-fired power plants after installation of flue gas desulfurization devices. The North China Plain has the world's most severe SO2 pollution, but a decreasing trend has been observed since 2011, with about a 50 % reduction in 2012–2015, due to an economic slowdown and government efforts to restrain emissions from the power and industrial sectors. In contrast, India's SO2 and NO2 levels from coal power plants and smelters are growing at a fast pace, increasing by more than 100 and 50 %, respectively, from 2005 to 2015. Several SO2 hot spots observed over the Persian Gulf are probably related to oil and gas operations and indicate a possible underestimation of emissions from these sources in bottom-up emission inventories. Overall, OMI observations have proved valuable in documenting rapid changes in air

  11. Retrieval columns of SO2 in industrial chimneys using DOAS passive in traverse

    Science.gov (United States)

    Galicia Mejía, Rubén; de la Rosa Vázquez, José Manuel; Sosa Iglesias, Gustavo

    2011-10-01

    The optical Differential Optical Absorption Spectroscopy (DOAS) is a technique to measure pollutant emissions like SO2, from point sources and total fluxes in the atmosphere. Passive DOAS systems use sunlight like source. Measurements with such systems can be made in situ and in real time. The goal of this work is to report the implementation of hardware and software of a portable system to evaluate the pollutants emitted in the atmosphere by industrial chimneys. We show SO2 measurements obtained around PEMEX refinerys in Tula Hidalgo that enables the identification of their pollution degree with the knowledge of speed wind.

  12. Updated SO2 emission estimates over China using OMI/Aura observations

    Science.gov (United States)

    Elissavet Koukouli, Maria; Theys, Nicolas; Ding, Jieying; Zyrichidou, Irene; Mijling, Bas; Balis, Dimitrios; van der A, Ronald Johannes

    2018-03-01

    The main aim of this paper is to update existing sulfur dioxide (SO2) emission inventories over China using modern inversion techniques, state-of-the-art chemistry transport modelling (CTM) and satellite observations of SO2. Within the framework of the EU Seventh Framework Programme (FP7) MarcoPolo (Monitoring and Assessment of Regional air quality in China using space Observations) project, a new SO2 emission inventory over China was calculated using the CHIMERE v2013b CTM simulations, 10 years of Ozone Monitoring Instrument (OMI)/Aura total SO2 columns and the pre-existing Multi-resolution Emission Inventory for China (MEIC v1.2). It is shown that including satellite observations in the calculations increases the current bottom-up MEIC inventory emissions for the entire domain studied (15-55° N, 102-132° E) from 26.30 to 32.60 Tg annum-1, with positive updates which are stronger in winter ( ˜ 36 % increase). New source areas were identified in the southwest (25-35° N, 100-110° E) as well as in the northeast (40-50° N, 120-130° E) of the domain studied as high SO2 levels were observed by OMI, resulting in increased emissions in the a posteriori inventory that do not appear in the original MEIC v1.2 dataset. Comparisons with the independent Emissions Database for Global Atmospheric Research, EDGAR v4.3.1, show a satisfying agreement since the EDGAR 2010 bottom-up database provides 33.30 Tg annum-1 of SO2 emissions. When studying the entire OMI/Aura time period (2005 to 2015), it was shown that the SO2 emissions remain nearly constant before the year 2010, with a drift of -0.51 ± 0.38 Tg annum-1, and show a statistically significant decline after the year 2010 of -1.64 ± 0.37 Tg annum-1 for the entire domain. Similar findings were obtained when focusing on the greater Beijing area (30-40° N, 110-120° E) with pre-2010 drifts of -0.17 ± 0.14 and post-2010 drifts of -0.47 ± 0.12 Tg annum-1. The new SO2 emission inventory is publicly available and forms

  13. Novel Guanidinium-Based Ionic Liquids for Highly Efficient SO2 Capture.

    Science.gov (United States)

    Lu, Xiaoxing; Yu, Jing; Wu, Jianzhou; Guo, Yongsheng; Xie, Hujun; Fang, Wenjun

    2015-06-25

    The application of ionic liquids (ILs) for acidic gas absorption has long been an interesting and challenging issue. In this work, the ethyl sulfate ([C2OSO3](-)) anion has been introduced into the structure of guanidinium-based ILs to form two novel low-cost ethyl sulfate ILs, namely 2-ethyl-1,1,3,3-tetramethylguanidinium ethyl sulfate ([C2(2)(C1)2(C1)2(3)gu][C2OSO3]) and 2,2-diethyl-1,1,3,3-tetramethylguanidinium ethyl sulfate ([(C2)2(2)(C1)2(C1)2(3)gu][C2OSO3]). The ethyl sulfate ILs, together with 2-ethyl-1,1,3,3-tetramethylguanidinium bis(trifluoromethylsulfonyl)imide ([C2(2)(C1)2(C1)2(3)gu][NTf2]) and 2,2-diethyl-1,1,3,3-tetramethylguanidinium bis(trifluoromethylsulfonyl)imide ([(C2)2(2)(C1)2(C1)2(3)gu][NTf2]), are employed to evaluate the SO2 absorption and desorption performance. The recyclable ethyl sulfate ILs demonstrate high absorption capacities of SO2. At a low pressure of 0.1 bar and at 20 °C, 0.71 and 1.08 mol SO2 per mole of IL can be captured by [C2(2)(C1)2(C1)2(3)gu][C2OSO3] and [(C2)2(2)(C1)2(C1)2(3)gu][C2OSO3], respectively. The absorption enthalpy for SO2 absorption with [C2(2)(C1)2(C1)2(3)gu][C2OSO3] and [(C2)2(2)(C1)2(C1)2(3)gu][C2OSO3] are -3.98 and -3.43 kcal mol(-1), respectively. While those by [C2(2)(C1)2(C1)2(3)gu][NTf2] and [(C2)2(2)(C1)2(C1)2(3)gu][NTf2] turn out to be only 0.17 and 0.24 mol SO2 per mole of IL under the same conditions. It can be concluded that the guanidinium ethyl sulfate ILs show good performance for SO2 capture. Quantum chemistry calculations reveal nonbonded weak interactions between the ILs and SO2. The anionic moieties of the ILs play an important role in SO2 capture on the basis of the consistently experimental and computational results.

  14. Catalytic Activity and Deactivation of SO2 Oxidation Catalysts in Simulated Power Plant Flue Gases

    DEFF Research Database (Denmark)

    Masters, Stephen G.; Chrissanthopoulos, Asthanassios; Eriksen, Kim Michael

    1997-01-01

    The catalyst deactivation and the simultaneious formation of compounds in commercial SO2 oxidation catalysts have been studied by combined activity measurements and in situ EPR spectroscopy in the temperature range 350-480 C in wet and dry simulated power plant flue gas.......The catalyst deactivation and the simultaneious formation of compounds in commercial SO2 oxidation catalysts have been studied by combined activity measurements and in situ EPR spectroscopy in the temperature range 350-480 C in wet and dry simulated power plant flue gas....

  15. 44 CFR 5.8 - Records involved in litigation or other judicial process.

    Science.gov (United States)

    2010-10-01

    ... litigation or other judicial process. 5.8 Section 5.8 Emergency Management and Assistance FEDERAL EMERGENCY... Provisions § 5.8 Records involved in litigation or other judicial process. Where there is reason to believe that any records requested may be involved in litigation or other judicial process in which the United...

  16. Hydrogen permeation and corrosion behavior of high strength steel MCM 430 in cyclic wet-dry SO2 environment

    International Nuclear Information System (INIS)

    Nishimura, Rokuro; Shiraishi, Daisuke; Maeda, Yasuaki

    2004-01-01

    Hydrogen permeation caused by corrosion under a cyclic wet (2 h)-dry (10 h) SO 2 condition was investigated for a high strength steel of MCM 430 by using an electrochemical technique in addition to the corrosion behavior obtained from weight loss measurement and the determination of corrosion products by using X-ray diffraction method. The hydrogen content converted from hydrogen permeation current density was observed in both wet and dry periods. The origin of proton was estimated to be from (1) the hydrolysis of ferrous ions, (2) the oxidation of ferrous ions and ferrous hydroxide, and (3) hydrolysis of SO 2 and formation of FeSO 4 , but not from the dissociation of H 2 O. With respect to the determination of the corrosion products consisting of inner (adherent) and outer (not adherent) layers, the outer layer is composed of α-FeOOH, amorphous phase and γ-FeOOH, where α-FeOOH increases with the increase in the wet-dry cycle, and amorphous phase shows the reverse trend. The corrosion product in the inner layer is mainly Fe 3 O 4 with them. On the basis of the results obtained, the role of the dry or wet period, the effect of SO 2 and the corrosion process during the cyclic wet-dry periods were discussed

  17. Validation Studies of the Accuracy of Various SO2 Gas Retrievals in the Thermal InfraRed (8-14 μm)

    Science.gov (United States)

    Gabrieli, A.; Wright, R.; Lucey, P. G.; Porter, J. N.; Honniball, C.; Garbeil, H.; Wood, M.

    2016-12-01

    Quantifying hazardous SO2 in the atmosphere and in volcanic plumes is important for public health and volcanic eruption prediction. Remote sensing measurements of spectral radiance of plumes contain information on the abundance of SO2. However, in order to convert such measurements into SO2 path-concentrations, reliable inversion algorithms are needed. Various techniques can be employed to derive SO2 path-concentrations. The first approach employs a Partial Least Square Regression model trained using MODTRAN5 simulations for a variety of plume and atmospheric conditions. Radiances at many spectral wavelengths (8-14 μm) were used in the algorithm. The second algorithm uses measurements inside and outside the SO2 plume. Measurements in the plume-free region (background sky) make it possible to remove background atmospheric conditions and any instrumental effects. After atmospheric and instrumental effects are removed, MODTRAN5 is used to fit the SO2 spectral feature and obtain SO2 path-concentrations. The two inversion algorithms described above can be compared with the inversion algorithm for SO2 retrievals developed by Prata and Bernardo (2014). Their approach employs three wavelengths to characterize the plume temperature, the atmospheric background, and the SO2 path-concentration. The accuracy of these various techniques requires further investigation in terms of the effects of different atmospheric background conditions. Validating these inversion algorithms is challenging because ground truth measurements are very difficult. However, if the three separate inversion algorithms provide similar SO2 path-concentrations for actual measurements with various background conditions, then this increases confidence in the results. Measurements of sky radiance when looking through SO2 filled gas cells were collected with a Thermal Hyperspectral Imager (THI) under various atmospheric background conditions. These data were processed using the three inversion approaches

  18. Ultrastructural study of the effect of air pollution by SO2 on the ...

    African Journals Online (AJOL)

    changes in airways has been suggested by smog incidents, but has not been evaluated by experiments. So, this study was done to answer the following questions: (1) What morphologic changes are produced by repeated injury to airway epithelial cells by SO2? (2) What is the time course of these morphologic features?

  19. What is Eating Ozone? Thermal Reactions between SO2 And O3: Implications for Icy Environments

    Science.gov (United States)

    Loeffler, Mark J.; Hudson, Reggie L.

    2016-01-01

    Laboratory studies are presented, showing for the first time that thermally driven reactions in solid H2O+SO2+O3 mixtures can occur below 150 K, with the main sulfur-containing product being bisulfate (HSO4(-)). Using a technique not previously applied to the low-temperature kinetics of either interstellar or solar system ice analogs, we estimate an activation energy of 32 kJ per mol for HSO4(-) formation. These results show that at the temperatures of the Jovian satellites, SO2 and O3 will efficiently react making detection of these molecules in the same vicinity unlikely. Our results also explain why O3 has not been detected on Callisto and why the SO2 concentration on Callisto appears to be highest on that world's leading hemisphere. Furthermore, our results predict that the SO2 concentration on Ganymede will be lowest in the trailing hemisphere, where the concentration of O3 is the highest. Our work suggests that thermal reactions in ices play a much more important role in surface and sub-surface chemistry than generally appreciated, possibly explaining the low abundance of sulfur-containing molecules and the lack of ozone observed in comets and interstellar ices.

  20. SORBENT/UREA SLURRY INJECTION FOR SIMULTANEOUS SO2/NOX REMOVAL

    Science.gov (United States)

    The combination of sorbent injection and selective noncatalytic reduction (SNCR) technologies has been investigated for simulataneous SO2/NOx removal. A slurry composed of a urea-based solution and various Ca-based sorbents was injected at a range of tempera...

  1. Projection of SO2, NOx, NMVOC, particulate matter and black carbon emissions - 2015-2030

    DEFF Research Database (Denmark)

    Nielsen, Ole-Kenneth; Plejdrup, Marlene Schmidt; Hjelgaard, Katja Hossy

    This report contains a description of models and background data for projection of SO2, NOX, NMVOC, PM2.5 and black carbon for Denmark. The emissions are projected to 2030 using basic scenarios together with the expected results of a few individual policy measures. Official Danish forecasts...

  2. ACTIVATION AND REACTIVITY OF NOVEL CALCIUM-BASED SORBENTS FOR DRY SO2 CONTROL IN BOILERS

    Science.gov (United States)

    Chemically modified calcium hydroxide (Ca(OH)2) sorbents developed in the U.S. Environmental Protection Agency's Air and Energy Engineering Research Laboratory (AEERL) for sulfur dioxide (SO2) control in utility boilers were tested in an electrically heated, bench-scale isotherma...

  3. UV Fourier transform measurements of tropospheric O3, NO2, SO2, benzene, and toluene

    International Nuclear Information System (INIS)

    Vandaele, A.C.; Tsouli, A.; Carleer, M.; Colin, R.

    2002-01-01

    Using the differential optical absorption spectroscopy (DOAS) technique and a Fourier transform spectrometer, NO 2 , SO 2 , O 3 , benzene, and toluene were measured during three measurement campaigns held in Brussels in 1995, 1996, and 1997. The O 3 concentrations could be explained as the results of the local photochemistry and the dynamical properties of the mixing layer. NO 2 concentrations were anti-correlated to the O 3 concentrations, is expected. SO 2 also showed a pronounced dependence on car traffic. Average benzene and toluene concentrations were, respectively 1.7 ppb and between 4.4 and 6.6 pbb, but high values of toluene up to 98.8 ppb were observed. SO 2 concentrations and to a lesser extent, those of NO 2 and O 3 , were dependent on the wind direction. Ozone in Brussels has been found to be influenced by the meteorological conditions prevailing in central Europe. Comparisons with other measurements have shown that O 3 and SO 2 data are in general in good agreement, but our NO 2 concentrations seem to be generally higher. (author)

  4. Effects and Mechanism of SO2 Inhalation on Rat Myocardial Collagen Fibers.

    Science.gov (United States)

    Chen, Ping; Qiao, Decai; Liu, Xiaoli

    2018-03-21

    BACKGROUND This study investigates the effects and mechanism of sulfur dioxide (SO2) inhalation and exercise on rat myocardial collagen fiber. MATERIAL AND METHODS The rats were randomly divided into 4 groups: a control group (RG), an exercise group (EG), an SO2 pollution group (SRG), and an SO2 pollution and exercise group (SEG). Body weight, cardiac index, and left ventricular index in each group were compared. The myocardial hydroxyproline (Hyp) concentration was determined by pepsin acid hydrolysis. The interstitial myocardial collagen expression was measured by Sirius Red F3B in saturated carbazotic acid. The local myocardial angiotensin II type 1 receptor (AT1R) and connective tissue growth factor (CTGF) expression was tested by immunohistochemistry SABC method. RESULTS Compared with RG, the weight growth rate of EG, SRG, and SEG decreased significantly (PSO2 inhalation and exercise will not only offset beneficial health effects of movement on the cardiovascular system, but also produce more unfavorable influences. People should pay attention to their environment when exercising, and try to avoid exercising in environments with SO2 pollution.

  5. Modelling the spatial distribution of SO2 and NO(x) emissions in Ireland

    NARCIS (Netherlands)

    Kluizenaar, Y.de; Aherne, J.; Farrell, E.P.

    2001-01-01

    The spatial distributions of sulphur dioxide (SO2) and nitrogen oxides (NO(x)) emissions are essential inputs to models of atmospheric transport and deposition. Information of this type is required for international negotiations on emission reduction through the critical load approach.

  6. 76 FR 30602 - Response To Petition From New Jersey Regarding SO2

    Science.gov (United States)

    2011-05-26

    ... ENVIRONMENTAL PROTECTION AGENCY 40 CFR Part 52 [EPA-HQ-OAR-2011-0081; FRL-9312-1] RIN 2060-AQ69 Response To Petition From New Jersey Regarding SO2 Emissions From the Portland Generating Station AGENCY: Environmental Protection Agency (EPA). [[Page 30603

  7. Physico-Chemical and Structural Properties of DeNOx and SO2 Oxidation Catalysts

    DEFF Research Database (Denmark)

    Masters, Stephen Grenville; Oehlers, Cord; Nielsen, Kurt

    1996-01-01

    Commercial catalysts for NOx removal and SO2 oxidation and their model systems have been investigated by spectroscopic, thermal, electrochemical and X-ray methods. Structural information on the vanadium complexes and compounds as well as physico-chemical properties for catalyst model systems have...

  8. 78 FR 69337 - Approval and Promulgation of Air Quality Implementation Plans; Ohio; Ohio SO2

    Science.gov (United States)

    2013-11-19

    ... ENVIRONMENTAL PROTECTION AGENCY 40 CFR Part 52 [EPA-R05-OAR-2011-0672; FRL-9902-02-Region 5] Approval and Promulgation of Air Quality Implementation Plans; Ohio; Ohio SO2 Air Quality Rule Revisions AGENCY: Environmental Protection Agency (EPA). ACTION: Proposed rule. SUMMARY: On June 24, 2011, Ohio...

  9. Emissioner af SO2 og NOX fra kraftværker

    DEFF Research Database (Denmark)

    Illerup, J. B.; Bruun, H. G.

    Rapporten indeholder beregninger af SO2- og NOx- emissioner fra kraftværker, der er reguleret af kvoteloven. Emissionerne er for tre forskellige produktionsscenarier beregnet ud fra emissionsfaktorer baseret på EU-direktivet om store forbrændingsanlæg og emissionsfaktorer beregnet ud fra en...

  10. Aura OMI observations of regional SO2 and NO2 pollution changes from 2005 to 2015

    NARCIS (Netherlands)

    Krotkov, Nickolay A.; McLinden, Chris A.; Li, Can; Lamsal, Lok N.; Celarier, Edward A.; Marchenko, Sergey V.; Swartz, William H.; Bucsela, Eric J.; Joiner, Joanna; Duncan, Bryan N.; Boersma, Folkert; Veefkind, J.P.; Levelt, Pieternel F.; Fioletov, Vitali E.; Dickerson, Russell R.; He, Hao; Lu, Zifeng; Streets, David G.

    2016-01-01

    The Ozone Monitoring Instrument (OMI) onboard NASA's Aura satellite has been providing global observations of the ozone layer and key atmospheric pollutant gases, such as nitrogen dioxide (NO2) and sulfur dioxide (SO2), since October 2004. The data products from the same instrument provide

  11. Sulfur Dioxide (SO2) Primary Standards Documents from Current Review - Federal Register Notices

    Science.gov (United States)

    EPA develops and publishes a notice of proposed rulemaking regarding the review of the SO2 national ambient air quality standards (NAAQS). A public comment period follows. Taking into account comments received on the proposed rule, EPA issues a final rule.

  12. 77 FR 26444 - Revisions to Final Response To Petition From New Jersey Regarding SO2

    Science.gov (United States)

    2012-05-04

    ... ENVIRONMENTAL PROTECTION AGENCY 40 CFR Part 52 [EPA-HQ-OAR-2011-0081; FRL-9660-5] RIN 2060-AR42 Revisions to Final Response To Petition From New Jersey Regarding SO2 Emissions From the Portland Generating Station AGENCY: Environmental Protection Agency (EPA). ACTION: Final rule. SUMMARY: This action amends the...

  13. 78 FR 69299 - Approval and Promulgation of Air Quality Implementation Plans; Ohio; Ohio SO2

    Science.gov (United States)

    2013-11-19

    ... ENVIRONMENTAL PROTECTION AGENCY 40 CFR Part 52 [EPA-R05-OAR-2011-0672; FRL-9902-03-Region 5] Approval and Promulgation of Air Quality Implementation Plans; Ohio; Ohio SO2 Air Quality Rule Revisions AGENCY: Environmental Protection Agency (EPA). ACTION: Direct final rule. SUMMARY: On June 24, 2011, Ohio...

  14. Analysis on concentration variety characteristics of SO2/NO2 in Chengdu city, southwest China

    Science.gov (United States)

    Wang, C.; Xiao, T.; Luo, Q.; WU, L.

    2017-12-01

    SO2 and NO2, the important gaseous precursors of atmospheric fine particles, are closely related to urban air quality. Chengdu located in the western China, is the capital city of Sichuan province. Though Sichuan province is one of four heavily polluted areas in China, the air pollution research in Chengdu is in a relative lack, when compared to developed cities as Beijing, Guangzhou, etc. This paper, based on characteristics of SO2 and NO2 in Chengdu, shows that: the average concentration of SO2, NO2 was 25.29 (mainly in the rage 10-40 ), 64.41 (mainly in the range 30-80 ), respectively. There is a similar annual and seasonal variation for them, yet significant differences in diurnal variation. Except summer, the air condition in Chengdu is seriously affected by SO2 and NO2, while the latter plays a more significant role. Multiple regression has good fitting performance to the diurnal variation in Chengdu. The purification efficiency of precipitation in different magnitude is also discussed. Key words: Chengdu; Pollution gas; Variety characteristics Acknowledgements: This study was supported by Pollution program in Wenjiang District, National Natural Science Foundation of China Fund Project (91337215,41575066), National Science and Technology Support Program(2015BAC03B05),Special Fund for Meteorological Re-search in the Public Interest (GYHY201406015),National Key Basic Research Program (2013CB733206), and Risk Assessment System of Significant Climate Events in Tibet (14H046), Scientific Research Foundation of CUIT (CRF201606)

  15. Model simulations of the competing climatic effects of SO2 and CO2

    Science.gov (United States)

    Kaufman, Yoram J.; Chou, Ming-Dah

    1993-01-01

    Sulfur dioxide-derived cloud condensation nuclei are expected to enhance the planetary albedo, thereby cooling the planet. This effect might counteract the global warming expected from enhanced greenhouse gases. A detailed treatment of the relationship between fossil fuel burning and the SO2 effect on cloud albedo is implemented in a two-dimensional model for assessing the climate impact. Using a conservative approach, results show that the cooling induced by the SO2 emission can presently counteract 50 percent of the CO2 greenhouse warming. Since 1980, a strong warming trend has been predicted by the model: 0.15 C during the 1980-1990 period alone. The model predicts that by the year 2060 the SO2 cooling reduces climate warming by 0.5 C or 25 percent for the Intergovernmental Panel on Climate Change (IPCC) business as usual (BAU) scenario and 0.2 C or 20 percent for scenario D (for a slow pace of fossil fuel burning). The hypothesis is examined that the different responses between the Northern Hemisphere and the Southern Hemisphere can be used to validate the presence of the SO2-induced cooling.

  16. Extended observations of volcanic SO2 and sulfate aerosol in the stratosphere

    NARCIS (Netherlands)

    Carn, S.A.; Krotkov, N.A.; Yang, Kai; Hoff, R.M.; Prata, A.J.; Krueger, A.J.; Loughlin, S.C.; Levelt, P.F.

    2007-01-01

    Sulfate aerosol produced after injection of sulfur dioxide (SO2) into the stratosphere by volcanic eruptions can trigger climate change. We present new satellite data from the Ozone Monitoring Instrument (OMI) and Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observations (CALIPSO) missions

  17. Evaluation of the Mycobacterium tuberculosis SO2 vaccine using a natural tuberculosis infection model in goats.

    Science.gov (United States)

    Bezos, J; Casal, C; Álvarez, J; Roy, A; Romero, B; Rodríguez-Bertos, A; Bárcena, C; Díez, A; Juste, R; Gortázar, C; Puentes, E; Aguiló, N; Martín, C; de Juan, L; Domínguez, L

    2017-05-01

    The development of new vaccines against animal tuberculosis (TB) is a priority for improving the control and eradication of this disease, particularly in those species not subjected to compulsory eradication programmes. In this study, the protection conferred by the Mycobacterium tuberculosis SO 2 experimental vaccine was evaluated using a natural infection model in goats. Twenty-six goats were distributed in three groups: (1) 10 goats served as a control group; (2) six goats were subcutaneously vaccinated with BCG; and (3) 10 goats were subcutaneously vaccinated with SO 2 . Four months after vaccination, all groups were merged with goats infected with Mycobacterium bovis or Mycobacterium caprae, and tested over a 40 week period using a tuberculin intradermal test and an interferon-γ assay for mycobacterial reactivity. The severity of lesions was determined at post-mortem examination and the bacterial load in tissues were evaluated by culture. The two vaccinated groups had significantly lower lesion and bacterial culture scores than the control group (P<0.05); at the end of the study, the SO 2 vaccinated goats had the lowest lesion and culture scores. These results suggest that the SO 2 vaccine provides some protection against TB infection acquired from natural exposure. Copyright © 2017 Elsevier Ltd. All rights reserved.

  18. Coal fly ash based carbons for SO2 removal from flue gases.

    Science.gov (United States)

    Rubio, B; Izquierdo, M T

    2010-07-01

    Two different coal fly ashes coming from the burning of two coals of different rank have been used as a precursor for the preparation of steam activated carbons. The performance of these activated carbons in the SO(2) removal was evaluated at flue gas conditions (100 degrees C, 1000 ppmv SO(2), 5% O(2), 6% H(2)O). Different techniques were used to determine the physical and chemical characteristics of the samples in order to explain the differences found in their behaviour. A superior SO(2) removal capacity was shown by the activated carbon obtained using the fly ash coming from a sub-bituminous-lignite blend. Experimental results indicated that the presence of higher amount of certain metallic oxides (Ca, Fe) in the carbon-rich fraction of this fly ash probably has promoted a deeper gasification in the activation with steam. A more suitable surface chemistry and textural properties have been obtained in this case which explains the higher efficiency shown by this sample in the SO(2) removal. Copyright (c) 2010 Elsevier Ltd. All rights reserved.

  19. Gas-phase hydrolysis of triplet SO2: A possible direct route to atmospheric acid formation

    Science.gov (United States)

    Donaldson, D. James; Kroll, Jay A.; Vaida, Veronica

    2016-07-01

    Sulfur chemistry is of great interest to the atmospheric chemistry of several planets. In the presence of water, oxidized sulfur can lead to new particle formation, influencing climate in significant ways. Observations of sulfur compounds in planetary atmospheres when compared with model results suggest that there are missing chemical mechanisms. Here we propose a novel mechanism for the formation of sulfurous acid, which may act as a seed for new particle formation. In this proposed mechanism, the lowest triplet state of SO2 (3B1), which may be accessed by near-UV solar excitation of SO2 to its excited 1B1 state followed by rapid intersystem crossing, reacts directly with water to form H2SO3 in the gas phase. For ground state SO2, this reaction is endothermic and has a very high activation barrier; our quantum chemical calculations point to a facile reaction being possible in the triplet state of SO2. This hygroscopic H2SO3 molecule may act as a condensation nucleus for water, giving rise to facile new particle formation (NPF).

  20. Study of the components of quality in SO2-free wines obtained by innovative vinification protocols. Evaluation of the pre-fermentative addition of lysozyme and oenological tannins.

    OpenAIRE

    Sonni, Francesca

    2010-01-01

    The research performed during the PhD candidature was intended to evaluate the quality of white wines, as a function of the reduction in SO2 use during the first steps of the winemaking process. In order to investigate the mechanism and intensity of interactions occurring between lysozyme and the principal macro-components of musts and wines, a series of experiments on model wine solutions were undertaken, focusing attention on the polyphenols, SO2, oenological tannins, pectines, ethanol, ...

  1. A Method for Correlation of Gravestone Weathering and Air Quality (SO2), West Amidlands, UK

    Science.gov (United States)

    Carlson, Michael John

    From the beginning of the Industrial Revolution through the environmental revolution of the 1970s Britain suffered the effects of poor air quality primarily from particulate matter and acid in the form of NOx and SO x compounds. Air quality stations across the region recorded SO 2 beginning in the 1960s however the direct measurement of air quality prior to 1960 is lacking and only anecdotal notations exist. Proxy records including lung tissue samples, particulates in sediments cores, lake acidification studies and gravestone weathering have all been used to reconstruct the history of air quality. A 120-year record of acid deposition reconstructed from lead-lettered marble gravestone weathering combined with SO2 measurements from the air monitoring network across the West Midlands, UK region beginning in the 1960s form the framework for this study. The study seeks to create a spatial and temporal correlation between the gravestone weathering and measured SO 2. Successful correlation of the dataset from 1960s to the 2000s would allow a paleo-air quality record to be generated from the 120-year record of gravestone weathering. Decadal gravestone weathering rates can be estimated by non-linear regression analysis of stone loss at individual cemeteries. Gravestone weathering rates are interpolated across the region through Empirical Bayesian Kriging (EBK) methods performed through ArcGISRTM and through a land use based approach based on digitized maps of land use. Both methods of interpolation allow for the direct correlation of gravestone weathering and measured SO2 to be made. Decadal scale correlations of gravestone weathering rates and measured SO2 are very weak and non-existent for both EBK and the land use based approach. Decadal results combined together on a larger scale for each respective method display a better visual correlation. However, the relative clustering of data at lower SO2 concentrations and the lack of data at higher SO2 concentrations make the

  2. Changes in polyphenol profile of dried apricots containing SO2 at various concentrations during storage.

    Science.gov (United States)

    Altındağ, Melek; Türkyılmaz, Meltem; Özkan, Mehmet

    2018-05-01

    Changes in polyphenols have important effects on the quality (especially color) and health benefits of dried apricots. SO 2 concentration, storage and the activities of polyphenol oxidase (PPO) and phenylalanine ammonia lyase (PAL) were factors which had significant effects on polyphenols. Polyphenol profile and activities of PPO and PAL in sulfured dried apricots (SDAs, 0, 451, 832, 2112 and 3241 mg SO 2 kg -1 ) were monitored during storage at 4, 20 and 30 °C for 379 days for the first time. Even the lowest SO 2 concentration (451 mg kg -1 ) was sufficient to inactivate PPO during the entire storage period. However, while SO 2 led to the increase in PAL activity of the samples (r = 0.767) before storage, PAL activities of SDAs decreased during storage. After 90 days of storage, PAL activity was determined in only non-sulfured dried apricots (NSDAs) and dried apricots containing 451 mg SO 2 kg -1 . Although the major polyphenol in NSDAs was epicatechin (611.4 mg kg -1 ), that in SDAs was chlorogenic acid (455-1508 mg kg -1 ), followed by epicatechin (0-426.8 mg kg -1 ), rutin (148.9-477.3 mg kg -1 ), ferulic acid (23.3-55.3 mg kg -1 ) and gallic acid (2.4-43.6 mg kg -1 ). After storage at 30 °C for 379 days, the major polyphenol in SDAs was gallic acid (706-2324 mg kg -1 ). However, the major polyphenol in NSDAs did not change after storage. The highest total polyphenol content was detected in SDAs containing 2112 mg SO 2 kg -1 and stored at 30 °C. To produce dried apricots having high polyphenol content, ∼2000 mg SO 2 kg -1 should be used. Low storage temperature (<30 °C) was not necessary for the protection of polyphenols. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

  3. CO2, SO2, and H2S Degassing Related to the 2009 Redoubt Eruption, Alaska

    Science.gov (United States)

    Werner, C. A.; Kelly, P. J.; Evans, W.; Doukas, M. P.; McGimsey, R. G.; Neal, C. A.

    2012-12-01

    The 2009 eruption of Redoubt Volcano, Alaska was particularly well monitored for volcanic gas emissions with 35 airborne measurements of CO2, SO2, and H2S that span from October 2008 to August 2010. Increases in CO2 degassing were detected up to 5 months prior to the eruption and varied between 3630 and 9020 tonnes per day (t/d) in the 6 weeks prior to the eruption. Increased pre-eruptive CO2 degassing was accompanied by comparatively low S emission, resulting in molar C/S ratios that ranged between 30-60. However, the C/S ratio dropped to 2.4 coincident with the first phreatic explosion on March 15, 2009, and remained steady during the explosive (March 22 - April 4, 2009), effusive dome-building (April 5 - July 1, 2009), and waning phases (August 2009 onward) of the eruption. Observations of ice-melt rates, melt water discharge, and water chemistry in the months leading up to the eruption suggested that surface waters represented drainage from surficial, perched reservoirs of condensed magmatic steam and glacial meltwater. While the surface waters were capable of scrubbing many thousands of t/d of SO2, sampling of these fluids revealed that only a few hundred tonnes of SO2 was reacting to a dissolved component each day. This is also much less than the ~ 2100 t/d SO2 expected from degassing of magma in the upper crust (3-6.5 km), where petrologic analysis shows the final magma equilibration occurred. Thus, the high pre-eruptive C/S ratios observed could reflect bulk degassing of upper-crustal magma followed by nearly complete loss of SO2 in a magmatic-hydrothermal system. Alternatively, high C/S ratios could be attributed to degassing of low silica andesitic magma that intruded into the mid-crust in the 5 months prior to eruption; modeling suggests that mixing of this magma with pre-existing high silica andesite magma or mush would have caused a reduction of the C/S ratio to a value consistent with that measured during the eruption. Monitoring emissions regularly

  4. Field test of available methods to measure remotely SO2 and NOx emissions from ships

    Science.gov (United States)

    Balzani Lööv, J. M.; Alfoldy, B.; Beecken, J.; Berg, N.; Berkhout, A. J. C.; Duyzer, J.; Gast, L. F. L.; Hjorth, J.; Jalkanen, J.-P.; Lagler, F.; Mellqvist, J.; Prata, F.; van der Hoff, G. R.; Westrate, H.; Swart, D. P. J.; Borowiak, A.

    2013-11-01

    Methods for the determination of ship fuel sulphur content and NOx emission factors from remote measurements have been compared in the harbour of Rotterdam and compared to direct stack emission measurements on the ferry Stena Hollandica. The methods were selected based on a review of the available literature on ship emission measurements. They were either optical (LIDAR, DOAS, UV camera), combined with model based estimates of fuel consumption, or based on the so called "sniffer" principle, where SO2 or NOx emission factors are determined from simultaneous measurement of the increase of CO2 and SO2 or NOx concentrations in the plume of the ship compared to the background. The measurements were performed from stations at land, from a boat, and from a helicopter. Mobile measurement platforms were found to have important advantages compared to the landbased ones because they allow to optimize the sampling conditions and to sample from ships on the open sea. Although optical methods can provide reliable results, it was found that at the state of the art, the "sniffer" approach is the most convenient technique for determining both SO2 and NOx emission factors remotely. The average random error on the determination of SO2 emission factors comparing two identical instrumental set-ups was 6%. However, it was found that apparently minor differences in the instrumental characteristics, such as response time, could cause significant differences between the emission factors determined. Direct stack measurements showed that about 14% of the fuel sulphur content was not emitted as SO2. This was supported by the remote measurements and is in agreement with the results of other field studies.

  5. Health risks of NO 2, SPM and SO 2 in Delhi (India)

    Science.gov (United States)

    Pandey, Jai Shanker; Kumar, Rakesh; Devotta, Sukumar

    There is increasingly growing evidence linking urban air pollution to acute and chronic illnesses amongst all age groups. Therefore, monitoring of ambient concentrations of various air pollutants as well as quantification of the dose inhaled becomes quite important, specially in view of the fact that in many countries, policy decisions for reducing pollutant concentrations are mainly taken on the basis of their health impacts. The dose when gets combined with the likely responses, indicates the ultimate health risk (HR). Thus, as an extension of our earlier studies, HR has been estimated for three pollutants, namely, suspended particulate matter (SPM), nitrogen dioxide (NO 2) and sulfur dioxide (SO 2) for Delhi City in India. For estimation and analyses, three zones have been considered, namely, residential, industrial and commercial. The total population has been divided into three age classes (infants, children and adults) with different body weights and breathing rates. The exercise takes into account age-specific breathing rates, body weights for different age categories and occupancy factors for different zones. Results indicate that health risks due to air pollution in Delhi are highest for children. For all age categories, health risks due to SO 2 (HR_SO 2) are the lowest. Hence, HR_SO 2 has been taken as the reference with respect to which HR values due to SPM and NO 2 have been compared. Taking into account all the age categories and their occupancy in different zones, average HR values for NO 2 and SPM turn out to be respectively 22.11 and 16.13 times more than that for SO 2. The present study can be useful in generating public awareness as well as in averting and mitigating the health risks.

  6. Patient involvement in a scientific advisory process: setting the research agenda for medical products.

    NARCIS (Netherlands)

    Elberse, J.E.; Pittens, C.A.C.M.; de Cock Buning, J.T.; Broerse, J.E.W.

    2012-01-01

    Patient involvement in scientific advisory processes could lead to more societally relevant advice. This article describes a case study wherein the Health Council of the Netherlands involved patient groups in an advisory process with a predefined focus: setting a research agenda for medical products

  7. Retrieval of volcanic SO2 from HIRS/2 using optimal estimation

    Science.gov (United States)

    Miles, Georgina M.; Siddans, Richard; Grainger, Roy G.; Prata, Alfred J.; Fisher, Bradford; Krotkov, Nickolay

    2017-07-01

    We present an optimal-estimation (OE) retrieval scheme for stratospheric sulfur dioxide from the High-Resolution Infrared Radiation Sounder 2 (HIRS/2) instruments on the NOAA and MetOp platforms, an infrared radiometer that has been operational since 1979. This algorithm is an improvement upon a previous method based on channel brightness temperature differences, which demonstrated the potential for monitoring volcanic SO2 using HIRS/2. The Prata method is fast but of limited accuracy. This algorithm uses an optimal-estimation retrieval approach yielding increased accuracy for only moderate computational cost. This is principally achieved by fitting the column water vapour and accounting for its interference in the retrieval of SO2. A cloud and aerosol model is used to evaluate the sensitivity of the scheme to the presence of ash and water/ice cloud. This identifies that cloud or ash above 6 km limits the accuracy of the water vapour fit, increasing the error in the SO2 estimate. Cloud top height is also retrieved. The scheme is applied to a case study event, the 1991 eruption of Cerro Hudson in Chile. The total erupted mass of SO2 is estimated to be 2300 kT ± 600 kT. This confirms it as one of the largest events since the 1991 eruption of Pinatubo, and of comparable scale to the Northern Hemisphere eruption of Kasatochi in 2008. This retrieval method yields a minimum mass per unit area detection limit of 3 DU, which is slightly less than that for the Total Ozone Mapping Spectrometer (TOMS), the only other instrument capable of monitoring SO2 from 1979 to 1996. We show an initial comparison to TOMS for part of this eruption, with broadly consistent results. Operating in the infrared (IR), HIRS has the advantage of being able to measure both during the day and at night, and there have frequently been multiple HIRS instruments operated simultaneously for better than daily sampling. If applied to all data from the series of past and future HIRS instruments, this

  8. Interactive effects between total SO2 , ethanol and storage temperature against Brettanomyces bruxellensis.

    Science.gov (United States)

    Edwards, C G; Oswald, T A

    2018-01-01

    Although Brettanomyces bruxellensis continues to be a problem during red winemaking due to formation of off-odours and flavours, few interactions between intrinsic and extrinsic conditions that would limit spoilage have been identified. Using a commercially prepared Merlot wine, a 3 × 2 × 2 complete factorial design was implemented with total SO 2 (0, 60 or 100 mg l -1 ), ethanol (13% or 14·5% v v -1 ) and storage temperature (15° or 18°C) as variables. Populations of two strains of B. bruxellensis isolated from Washington wines (I1a and F3) were monitored for 100 days before concentrations of 4-ethylphenol, 4-ethylguaiacol and volatile acidity were measured. In wines with 13% v v -1 ethanol and stored at 15°C, addition of 100 mg l -1 total SO 2 resulted in much longer lag phases (>40 days) compared with wines without sulphites. At 14·5% v v -1 ethanol, culturability did not recover from wines with 100 mg l -1 total SO 2 regardless of the storage temperature (15° or 18°C). A few significant interactions were noted between these parameters which also affected synthesis of metabolites. Thus, SO 2 , ethanol concentration and storage temperature should be together used as means to reduce infections by B. bruxellensis. The potential for utilizing SO 2 along with the ethanol and storage temperature was studied to inhibit the spoilage yeast, Brettanomyces bruxellensis, during cellar ageing of red wines. This report is the first to identify the existence of interactions between these parameters that affect growth and/or metabolism of the yeast (i.e., synthesis of 4-ethylphenol, 4-ethylguaiacol and volatile acidity). Based on current and past findings, recommendations are presented related to the use of potential antimicrobial synergies between SO 2 , ethanol concentration and storage temperatures. © 2017 The Society for Applied Microbiology.

  9. Sulfur dioxide (SO2 from MIPAS in the upper troposphere and lower stratosphere 2002–2012

    Directory of Open Access Journals (Sweden)

    M. Höpfner

    2015-06-01

    Full Text Available Vertically resolved distributions of sulfur dioxide (SO2 with global coverage in the height region from the upper troposphere to ~20 km altitude have been derived from observations by the Michelson Interferometer for Passive Atmospheric Sounding (MIPAS on Envisat for the period July 2002 to April 2012. Retrieved volume mixing ratio profiles representing single measurements are characterized by typical errors in the range of 70–100 pptv and by a vertical resolution ranging from 3 to 5 km. Comparison with observations by the Atmospheric Chemistry Experiment Fourier transform spectrometer (ACE-FTS revealed a slightly varying bias with altitude of −20 to 50 pptv for the MIPAS data set in case of volcanically enhanced concentrations. For background concentrations the comparison showed a systematic difference between the two major MIPAS observation periods. After debiasing, the difference could be reduced to biases within −10 to 20 pptv in the altitude range of 10–20 km with respect to ACE-FTS. Further comparisons of the debiased MIPAS data set with in situ measurements from various aircraft campaigns showed no obvious inconsistencies within a range of around ±50 pptv. The SO2 emissions of more than 30 volcanic eruptions could be identified in the upper troposphere and lower stratosphere (UTLS. Emitted SO2 masses and lifetimes within different altitude ranges in the UTLS have been derived for a large part of these eruptions. Masses are in most cases within estimations derived from other instruments. From three of the major eruptions within the MIPAS measurement period – Kasatochi in August 2008, Sarychev in June 2009 and Nabro in June 2011 – derived lifetimes of SO2 for the altitude ranges 10–14, 14–18 and 18–22 km are 13.3 ± 2.1, 23.6 ± 1.2 and 32.3 ± 5.5 days respectively. By omitting periods with obvious volcanic influence we have derived background mixing ratio distributions of SO2. At 10 km altitude these indicate an annual

  10. A Python Software Toolbox for the Analysis of SO2 Camera Data. Implications in Geosciences

    Directory of Open Access Journals (Sweden)

    Jonas Gliß

    2017-12-01

    Full Text Available Ultraviolet (UV SO2 cameras have become a common tool to measure and monitor SO2 emission rates, mostly from volcanoes but also from anthropogenic sources (e.g., power plants or ships. Over the past decade, the analysis of UV SO2 camera data has seen many improvements. As a result, for many of the required analysis steps, several alternatives exist today (e.g., cell vs. DOAS based camera calibration; optical flow vs. cross-correlation based gas-velocity retrieval. This inspired the development of Pyplis (Python plume imaging software, an open-source software toolbox written in Python 2.7, which unifies the most prevalent methods from literature within a single, cross-platform analysis framework. Pyplis comprises a vast collection of algorithms relevant for the analysis of UV SO2 camera data. These include several routines to retrieve plume background radiances as well as routines for cell and DOAS based camera calibration. The latter includes two independent methods to identify the DOAS field-of-view (FOV within the camera images (based on (1 Pearson correlation and (2 IFR inversion method. Plume velocities can be retrieved using an optical flow algorithm as well as signal cross-correlation. Furthermore, Pyplis includes a routine to perform a first order correction of the signal dilution effect (also referred to as light dilution. All required geometrical calculations are performed within a 3D model environment allowing for distance retrievals to plume and local terrain features on a pixel basis. SO2 emission rates can be retrieved simultaneously for an arbitrary number of plume intersections. Hence, Pyplis provides a state-of-the-art framework for more efficient and flexible analyses of UV SO2 camera data and, therefore, marks an important step forward towards more transparency, reliability and inter-comparability of the results. Pyplis has been extensively and successfully tested using data from several field campaigns. Here, the main features

  11. Vertical profiles for SO2 and SO on Venus from different one-dimensional simulations

    Science.gov (United States)

    Mills, Franklin P.; Jessup, Kandis-Lea; Yung, Yuk

    2017-10-01

    Sulfur dioxide (SO2) plays many roles in Venus’ atmosphere. It is a precursor for the sulfuric acid that condenses to form the global cloud layers and is likely a precursor for the unidentified UV absorber, which, along with CO2 near the tops of the clouds, appears to be responsible for absorbing about half of the energy deposited in Venus’ atmosphere [1]. Most published simulations of Venus’ mesospheric chemistry have used one-dimensional numerical models intended to represent global-average or diurnal-average conditions [eg, 2, 3, 4]. Observations, however, have found significant variations of SO and SO2 with latitude and local time throughout the mesosphere [eg, 5, 6]. Some recent simulations have examined local time variations of SO and SO2 using analytical models [5], one-dimensional steady-state solar-zenith-angle-dependent numerical models [6], and three-dimensional general circulation models (GCMs) [7]. As an initial step towards a quantitative comparison among these different types of models, this poster compares simulated SO, SO2, and SO/SO2 from global-average, diurnal-average, and solar-zenith-angle (SZA) dependent steady-state models for the mesosphere.The Caltech/JPL photochemical model [8] was used with vertical transport via eddy diffusion set based on observations and observationally-defined lower boundary conditions for HCl, CO, and OCS. Solar fluxes are based on SORCE SOLSTICE and SORCE SIM measurements from 26 December 2010 [9, 10]. The results indicate global-average and diurnal-average models may have significant limitations when used to interpret latitude- and local-time-dependent observations of SO2 and SO.[1] Titov D et al (2007) in Exploring Venus as a Terrestrial Planet, 121-138. [2] Zhang X et al (2012) Icarus, 217, 714-739. [3] Krasnopolsky V A (2012) Icarus, 218, 230-246. [4] Parkinson C D et al (2015) Planet Space Sci, 113-114, 226-236. [5] Sandor B J et al (2010) Icarus, 208, 49-60. [6] Jessup K-L et al (2015) Icarus, 258, 309

  12. Adoption of Emissions Abating Technologies by U.S. Electricity Producing Firms Under the SO2 Emission Allowance Market

    Science.gov (United States)

    Creamer, Gregorio Bernardo

    The objective of this research is to determine the adaptation strategies that coal-based, electricity producing firms in the United States utilize to comply with the emission control regulations imposed by the SO2 Emissions Allowance Market created by the Clean Air Act Amendment of 1990, and the effect of market conditions on the decision making process. In particular, I take into consideration (1) the existence of carbon contracts for the provision of coal that may a affect coal prices at the plant level, and (2) local and geographical conditions, as well as political arrangements that may encourage firms to adopt strategies that appear socially less efficient. As the electricity producing sector is a regulated sector, firms do not necessarily behave in a way that maximizes the welfare of society when reacting to environmental regulations. In other words, profit maximization actions taken by the firm do not necessarily translate into utility maximization for society. Therefore, the environmental regulator has to direct firms into adopting strategies that are socially efficient, i.e., that maximize utility. The SO 2 permit market is an instrument that allows each firm to reduce marginal emissions abatement costs according to their own production conditions and abatement costs. Companies will be driven to opt for a cost-minimizing emissions abatement strategy or a combination of abatement strategies when adapting to new environmental regulations or markets. Firms may adopt one or more of the following strategies to reduce abatement costs while meeting the emission constraints imposed by the SO2 Emissions Allowance Market: (1) continue with business as usual on the production site while buying SO2 permits to comply with environmental regulations, (2) switch to higher quality, lower sulfur coal inputs that will generate less SO2 emissions, or (3) adopting new emissions abating technologies. A utility optimization condition is that the marginal value of each input

  13. Stakeholder involvement activities in Slovakia. NRA's Commitment to Transparent Regulatory Process. Stakeholder Involvement in the French Regulatory Process - From Public Information to Public Participation. Stakeholder involvement in nuclear decision making in the Russian Federation

    International Nuclear Information System (INIS)

    Ziakova, Marta Chairperson; Nuclear Regulatory Authority of the Slovak Republic; Nuclear Regulation Authority - NRA; Ferapontov, Alexey

    2017-01-01

    Session 2 focused on the regulatory perspectives related to stakeholder involvement in the regulatory decision-making process. Presentations provided the audience with information regarding the international and national legal framework implemented in the Slovak Republic, in France, in Japan and in Russia. Examples of stakeholder involvement, as well as some tools used for this purpose, were presented and discussed. The value of consistency and complementarity between international and national requirements was highlighted. Presentations and discussion confirmed the very close tie between the way the stakeholder involvement process is conducted and the public confidence and perception of reliability the regulatory body may gain, or lose. The four presentations confirmed that stakeholder involvement is a key challenge for maintaining regulatory body credibility, independence and legitimacy. All countries confirmed their commitment to trying to make their stakeholder involvement processes as open, visible, transparent and comprehensive as possible. Involvement represents a long and permanent process which requires investment of time, human resources and money, as well as the ability to reach out, to listen, to share, and to take input into account, while keeping in view the goal of delivering decisions that are as rational and objective as possible. Involving stakeholders is more than informing or communicating. The earlier the stakeholders are involved in the decision-making process, the greater the chance of success. If losing credibility is easy, all regulatory bodies agreed on the long process needed to recover it

  14. UV photoabsorption cross sections of CO, N2, and SO2 for studies of the ISM and planetary atmospheres

    Science.gov (United States)

    Smith, Peter L.; Rufus, J.; Yoshino, K.; Parkinson, W. H.; Stark, Glenn; Pickering, Juliet C.; Thorne, A. P.

    2002-01-01

    We report high-resolution laboratory measurements of photoabsorption cross sections of CO, N2, and SO2 in the wavelength range 80 to 320 nm. The motivation is to provide the quantitative data that are needed to analyze observations of absorption by, and to model photochemical processes in, the interstellar medium and a number of planetary atmospheres. Because of the high resolution of the spectrometers used, we can minimize distortion of the spectrum that occurs when instrument widths are greater than the widths of spectral features being measured. In many cases, we can determine oscillator strengths of individual rotational lines - a unique feature of our work.

  15. Updated SO2 emission estimates over China using OMI/Aura observations

    Directory of Open Access Journals (Sweden)

    M. E. Koukouli

    2018-03-01

    Full Text Available The main aim of this paper is to update existing sulfur dioxide (SO2 emission inventories over China using modern inversion techniques, state-of-the-art chemistry transport modelling (CTM and satellite observations of SO2. Within the framework of the EU Seventh Framework Programme (FP7 MarcoPolo (Monitoring and Assessment of Regional air quality in China using space Observations project, a new SO2 emission inventory over China was calculated using the CHIMERE v2013b CTM simulations, 10 years of Ozone Monitoring Instrument (OMI/Aura total SO2 columns and the pre-existing Multi-resolution Emission Inventory for China (MEIC v1.2. It is shown that including satellite observations in the calculations increases the current bottom-up MEIC inventory emissions for the entire domain studied (15–55° N, 102–132° E from 26.30 to 32.60 Tg annum−1, with positive updates which are stronger in winter ( ∼  36 % increase. New source areas were identified in the southwest (25–35° N, 100–110° E as well as in the northeast (40–50° N, 120–130° E of the domain studied as high SO2 levels were observed by OMI, resulting in increased emissions in the a posteriori inventory that do not appear in the original MEIC v1.2 dataset. Comparisons with the independent Emissions Database for Global Atmospheric Research, EDGAR v4.3.1, show a satisfying agreement since the EDGAR 2010 bottom-up database provides 33.30 Tg annum−1 of SO2 emissions. When studying the entire OMI/Aura time period (2005 to 2015, it was shown that the SO2 emissions remain nearly constant before the year 2010, with a drift of −0.51 ± 0.38 Tg annum−1, and show a statistically significant decline after the year 2010 of −1.64 ± 0.37 Tg annum−1 for the entire domain. Similar findings were obtained when focusing on the greater Beijing area (30–40° N, 110–120° E with pre-2010 drifts of −0.17 ± 0.14 and post-2010

  16. The US SO2 AUCTION: A policy recommendation for future auctions

    International Nuclear Information System (INIS)

    Christensen, J.L.; Thinggaard Svendsen, G.

    1998-01-01

    An annual discriminative and revenue-neutral auction is linked to the new Acid Rain Program which allows electric utilities all over the US to trade SO2 emission permits. This innovative SO2 auction distributes 2% of the permits in circulation and takes place at the Chicago Board of Trade. Early results showed that the auction generated a clearing price signal lower than the market price. Now the auction price seems to be determined by the outside market price. Still, in the important starting phase, a non-discriminative auction design would probably have generated better price signals since potentially severe downward biases in both seller price offers and buyer bids are due to the discriminative feature of the EPA auction. (au) 30 refs

  17. Numerical Model of SO2 Scrubbing with Seawater Applied to Marine Engines

    Directory of Open Access Journals (Sweden)

    Lamas M. I.

    2016-04-01

    Full Text Available The present paper proposes a CFD model to study sulphur dioxide (SO2 absorption in seawater. The focus is on the treatment of marine diesel engine exhaust gas. Both seawater and distilled water were compared to analyze the effect of seawater alkalinity. The results indicate that seawater is more appropriate than distilled water due to its alkalinity, obtaining almost 100% cleaning efficiency for the conditions analyzed. This SO2 reduction meets the limits of SOx emission control areas (SECA when operating on heavy fuel oil. These numerical simulations were satisfactory validated with experimental tests. Such data are essential in designing seawater scrubbers and judging the operating cost of seawater scrubbing compared to alternative fuels.

  18. Land use patterns and SO2 and NO2 pollution in Ulaanbaatar, Mongolia.

    Science.gov (United States)

    Huang, Yu-Kai; Luvsan, Munkh-Erdene; Gombojav, Enkhjargal; Ochir, Chimedsuren; Bulgan, Jargal; Chan, Chang-Chuan

    2013-07-01

    We proposed to study spatial distribution and source contribution of SO2 and NO2 pollution in Ulaanbaatar, Mongolia. We collected 2-week ambient SO2 and NO2 concentration samples at 38 sites, which were classified by major sources of air pollution such as ger areas and/or major roads, in three seasons as warm (September, 2011), cold (November-December, 2011), and moderate (March, 2012) in Ulaanbaatar. The SO2 and NO2 concentrations were collected by Ogawa ambient air passive samplers and analyzed by ion chromatography and spectrophotometry methods, respectively. Stepwise regression models were used to estimate the contribution of emission proxies, such as the distance to major roads, ger areas, power plants, and city center, to the ambient concentrations of SO2 and NO2. We found that the SO2 and NO2 concentrations were significantly higher in the cold season than in the warm and moderate seasons at all 38 ambient sampling sites. The SO2 concentrations in 20 ger sites (46.60 ppb in the cold season and 17.82 ppb in the moderate season) were significantly higher than in 18 non-ger sites (23.35 ppb in the cold season and 12.53 ppb in the moderate season). The NO2 concentrations at 19 traffic/road sites (12.85 ppb in the warm season and 20.48 ppb in the moderate season) were significantly higher than those at 19 urban sites (7.60 ppb and 14.39 ppb in the moderate season). Multiple regression models show that SO2 concentrations decreased by 23% in the cold and 17% in the moderate seasons at 0.70 km from the ger areas, an average of all sampling sites, and by 29% in the moderate season at 4.83 km from the city center, an average of all sampling sites. Multiple regression models show that the NO2 concentrations at 4.83 km from the city center decreased by 38% in the warm and 29% in the moderate seasons. Our models also report that NO2 concentrations at 0.16 km from the main roads decreased by 15% and 9% in the warm and the moderate seasons, respectively, and by 16% in the

  19. Treatment of reduced sulphur compounds and SO2 by Gas Phase Advanced Oxidation

    DEFF Research Database (Denmark)

    Meusinger, Carl; Bluhme, Anders Brostrøm; Ingemar, Jonas L.

    2017-01-01

    Reduced sulphur compounds (RSCs) emitted from pig farms are a major problem for agriculture, due to their health and environmental impacts and foul odour. This study investigates the removal of RSCs, including H2S, and their oxidation product SO2 using Gas Phase Advanced Oxidation (GPAO). GPAO...... is a novel air cleaning technique which utilises accelerated atmospheric chemistry to oxidise pollutants before removing their oxidation products as particles. Removal efficiencies of 24.5% and 3.9% were found for 461 ppb of H2S and 714 ppb of SO2 in a laboratory system (volumetric flow Q = 75 m3/h......). A numerical model of the reactor system was developed to explore the basic features of the system; its output was in fair agreement with the experiment. The model verified the role of OH radicals in initiating the oxidation chemistry. All sulphur removed from the gas phase was detected as particulate matter...

  20. Prospects of utilization of electron beam irradiation technology to augment control of SO2 and other emissions from Chilean copper smelting plants

    International Nuclear Information System (INIS)

    Villanueva, L.; Ahumada, L.; Ellison, W.; Chmielewski, A.G.; Zimek, Z.

    1998-01-01

    Analysis of potential utilization of applicable SO 2 -removal process for reduced-SO 2 -strength off-gases, including electron-beam irradiation, for incrementally improving overall abatement of SO 2 /SO 3 emissions from existing copper smelting facilities in Chile has been carried out. Off-gases are characterized by SO 2 content higher than 3,000 ppm, a complex chemical composition and highly oxidizing conditions, along with cyclical and fluctuating generation, reflecting relatively severe service. Laboratory tests with simulated high-SO 2 -strength process gas were performed at Polish Institute of Nuclear Chemistry and Technology. Test work proved the technical feasibility of removing SO 2 from ultra-high SO 2 content smelter gases by E-beam irradiation with ammonia injection. A laboratory unit with flow rate of 20 Nm 3 /h equipped with electron accelerator of 800 keV beam energy was used. Influence of different parameters on SO 2 removal efficiency, like temperature, dose, ammonia stoichiometry and water vapor content, has been established. Tests covered a high SO 2 content range, 2,000 to 10,000 ppm. A generic design has been deviced to address system arrangement, performance and control requirements. It encompasses upgrading of in-plant ventilation to the extent required by health standards, together with gas cleaning system based on EB Process. The arrangement of the facilities provides for gathering and treating off-gas from selected fugitive emission sources on a continuous basis, at the same time in-drafting a minimum amount of tramp air. An introductory dry dedusting stage uses activated coke injection in conjunction with a fabric filter to efficiently treat raw gas to remove heavy metals, including arsenic, along with particulate matter. Main conclusion of the two major stages of this work, i.e. experimental tests and engineering oriented studies, is that the EB Process is a simple and appropriate, cost-effective, chemical process that would, on a site

  1. Consequence assessment for Airborne Releases of SO2 from the Y-12 Pilot Dechlorination Facility

    International Nuclear Information System (INIS)

    Pendergrass, W.R.

    1992-06-01

    The Atmospheric Turbulence and Diffusion Division was requested by the Department of Energy's Oak Ridge Operations Office to conduct a consequence assessment for potential atmospheric releases of SO 2 from the Y-12 Pilot Dechlorination Facility. The focus of the assessment was to identify ''worst'' case meteorology which posed the highest concentration exposure potential for both on-site as well as off-site populations. A series of plausible SO 2 release scenarios were provided by Y-12 for the consequence assessment. Each scenario was evaluated for predictions of downwind concentration, estimates of a five-minute time weighted average, and estimate of the dimension of the puff. The highest hazard potential was associated with Scenario 1, in which a total of eight SO 2 cylinders are released internally to the Pilot Facility and exhausted through the emergency venting system. A companion effort was also conducted to evaluate the potential for impact of releases of SO 2 from the Pilot Facility on the population of Oak Ridge. While specific transport trajectory data is not available for the Pilot Facility, extrapolations based on the Oak Ridge Site Survey and climatological records from the Y-12 meteorological program does not indicate the potential for impact on the city of Oak Ridge. Steering by the local topographical features severely limits the potential impact ares. Due to the lack of specific observational data, both tracer and meteorological, only inferences can be made concerning impact zones. It is recommended tat the Department of Energy Oak Ridge Operations examine the potential for off-site impact and develop the background data to prepare impact zones for releases of hazardous materials from the Y-12 facility

  2. Nitrile-functionalized tertiary amines as highly efficient and reversible SO2 absorbents.

    Science.gov (United States)

    Hong, Sung Yun; Kim, Heehwan; Kim, Young Jin; Jeong, Junkyo; Cheong, Minserk; Lee, Hyunjoo; Kim, Hoon Sik; Lee, Je Seung

    2014-01-15

    Three different types of nitrile-functionalized amines, including 3-(N,N-diethylamino)propionitrile (DEAPN), 3-(N,N-dibutylamino)propionitrile (DBAPN), and N-methyl-N,N-dipropionitrile amine (MADPN) were synthesized, and their SO2 absorption performances were evaluated and compared with those of hydroxy-functionalized amines such as N,N-diethyl-N-ethanol amine (DEEA), N,N-dibutyl-N-ethanol amine (DBEA), and N-methyl-N,N-diethanol amine (MDEA). Absorption-desorption cycle experiments clearly demonstrate that the nitrile-functionalized amines are more efficient than the hydroxy-functionalized amines in terms of absorption rate and regenerability. Computational calculations with DBEA and DBAPN revealed that DBEA bearing a hydroxyethyl group chemically interacts with SO2 through oxygen atom, forming an ionic compound with a covalently bound OSO2(-) group. On the contrary, DBAPN bearing a nitrile group physically interacts with SO2 through the nitrogen and the hydrogen atoms of the two methylene groups adjacent to the amino and nitrile functionalities. Copyright © 2013 Elsevier B.V. All rights reserved.

  3. Heat generation in lithium-thionyl chloride and lithium-SO2 cells

    Science.gov (United States)

    Cohen, R.; Melman, A.; Livne, N.; Peled, E.

    1992-09-01

    The effects of current density, temperature, depth of discharge (DOD), and storage on the heat generation rate and faradaic efficiency of Li/Tc and Li/SO2 cells have been determined. Several C-size commercial cells from different manufacturers have been tested. The faradaic efficiency for both systems was found to be very high, typically 96-100 percent even at high current density and high temperatures (55 C). It does not change much with DOD and decreases only slightly with the increase of current density and high temperature (tested up to 4.5 mA/sq cm at 50 percent DOD and 55 C). A performance degradation problem was found for some Li/TC cells. The heat factor, the ratio between the useful electric power and the thermal power generated by the cell, is about the same for fresh Li/TC cells and Li/SO2 cells. However, some Li/TC cells stored for 3 years showed a poor heat factor. It was confirmed that the maximum thermoneutral voltage for the Li/TC and Li/SO2 cells is 3.80 and 3.22 V, respectively.

  4. 76 FR 19661 - Response to Petition From New Jersey Regarding SO2

    Science.gov (United States)

    2011-04-07

    ...In this action, EPA proposes to make a finding that the coal- fired Portland Generating Station (Portland Plant) in Upper Mount Bethel Township, Northampton County, Pennsylvania, is emitting air pollutants in violation of the interstate transport provisions of the Clean Air Act (CAA or Act). Specifically, EPA is proposing to find that emissions of sulfur dioxide (SO2) from the Portland Plant significantly contribute to nonattainment and interfere with maintenance of the 1-hour SO2 national ambient air quality standard (NAAQS) in New Jersey. This finding is proposed in response to a petition submitted by the State of New Jersey Department of Environmental Protection (NJDEP) on September 17, 2010. In this action, EPA is also proposing emission limitations and compliance schedules to ensure that the Portland Plant will no longer significantly contribute to nonattainment, and no longer interfere with maintenance of the 1- hour SO2 NAAQS, thereby permitting continued operation of the Portland Plant beyond the 3-month limit established by the CAA for sources subject to such a finding.

  5. Airborne emission measurements of SO2, NOx and particles from individual ships using sniffer technique

    Science.gov (United States)

    Beecken, J.; Mellqvist, J.; Salo, K.; Ekholm, J.; Jalkanen, J.-P.

    2013-12-01

    A dedicated system for airborne ship emission measurements of SO2, NOx and particles has been developed and used from several small aircrafts. The system has been adapted for fast response measurements at 1 Hz and the use of several of the instruments is unique. The uncertainty of the given data is about 20.3% for SO2 and 23.8% for NOx emission factors. Multiple measurements of 158 ships measured from the air on the Baltic and North Sea during 2011 and 2012 show emission factors of 18.8 ± 6.5 g kgfuel-1, 66.6 ± 23.4 g kgfuel-1, and 1.8 ± 1.3 × 1016 particles kgfuel-1 for SO2, NOx and particle number respectively. The particle size distributions were measured for particle diameters between 15 and 560 nm. The mean sizes of the particles are between 50 and 62 nm dependent on the distance to the source and the number size distribution is mono-modal. Concerning the sulfur fuel content 85% of the ships comply with the IMO limits. The sulfur emission has decreased compared to earlier measurements from 2007 to 2009. The presented method can be implemented for regular ship compliance monitoring.

  6. Airborne emission measurements of SO2 , NOx and particles from individual ships using a sniffer technique

    Science.gov (United States)

    Beecken, J.; Mellqvist, J.; Salo, K.; Ekholm, J.; Jalkanen, J.-P.

    2014-07-01

    A dedicated system for airborne ship emission measurements of SO2, NOx and particles has been developed and used from several small aircraft. The system has been adapted for fast response measurements at 1 Hz, and the use of several of the instruments is unique. The uncertainty of the given data is about 20% for SO2 and 24% for NOx emission factors. The mean values with one standard deviation for multiple measurements of 158 ships measured from the air on the Baltic and North Sea during 2011 and 2012 show emission factors of 18.8 ± 6.5 g kg-1 fuel , 66.6 ± 23.4 g kg-1 fuel and 1.8 ± 1.3 1016 particles kg-1 fuel for SO2, NOx and particle number, respectively. The particle size distributions were measured for particle diameters between 15 and 560 nm. The mean sizes of the particles are between 45 and 54 nm dependent on the distance to the source, and the number size distribution is monomodal. Concerning the sulfur fuel content, around 85% of the monitored ships comply with the International Maritime Organization (IMO) limits. The reduction of the sulfur emission control area (SECA) limit from 1.5 to 1% in 2010 appears to have contributed to reduction of sulfur emissions that were measured in earlier studies from 2007 to 2009. The presented method can be implemented for regular ship compliance monitoring.

  7. Continuation of Global NO2 and SO2 Monitoring with Suomi NPP OMPS

    Science.gov (United States)

    Yang, K.; Zhang, H.; Wang, J.; Ge, C.; Wang, Y.

    2017-12-01

    We have produced high-quality NO2 and SO2 standard products (named NMNO2 and NMSO2 respectively) from the SNPP OMPS-NM daily global observations. These OMPS standard products have been archived and publicly released at NASA Goddard Earth Sciences Data and Information Services Center (https://daac.gsfc.nasa.gov/information/news/595e9675624016d1af392c73/omps-nm-no- 2-and-so-2-l-2-data-products-released). Analyses and comparisons have demonstrated that the qualities of these OMPS standard products match or surpass those of the corresponding OMI products, enabling the continuity and extension of these two key standard Earth System Data Records (ESDRs) that begun with NASA's EOS Aura mission using the SNPP observations. In this presentation, we summarize the new techniques and algorithm advances that improve the accuracy and consistency of these ESDRs from satellite observations, and highlight the regional changes in NO2 and SO2 detected from half a decade of SNPP OMPS observations.

  8. NOx, N2O and SO2 emissions from pressurized fluidized bed combustion

    International Nuclear Information System (INIS)

    Korpela, T.; Lu Yong

    1995-01-01

    This project continues the analysis of available data from the experimental work at the Otaniemi PFBC test rig, including LIEKKI project 4-1a and 4- 4 during the past years. The study concentrates on the effects of the operating parameters on gas emissions, such as NO x , N 2 O and SO 2 , under pressurized conditions. The aim of the study is to prepare the database from the available data and make empirical correlations for estimating nitrogen oxides and sulphur dioxide emissions from PFBC as a function of significant operating parameters and fuel properties. The major aspect in this work is that the correlations, in general, are also available for existing data in the literature. These correlations may facilitate preliminary FBC design by estimating NO x , N 2 O and SO 2 emissions based on the fuel selected and the operating conditions employed. In addition, the fuel properties selected in the correlations on the basis of statistical inference may lend insight into the mechanisms of the formation and destruction of NO x , N 2 O and SO 2 Therefore, the results are expected to be valuable for energy producers, FBC boiler manufacturers. (author)

  9. Sodium bicarbonate in-duct injection with sodium sulfate recovery for SO2/NOx control

    International Nuclear Information System (INIS)

    Bennett, R.; Darmstaedter, E.

    1991-01-01

    Dry sodium injection with sodium bicarbonate has been used commercially at industrial sites since the mid 1980's. In the past three years, five full scale commercial demonstrations have been completed on electric utility coal fired units. Up to 75% SO 2 removal with 0-40% NO x removal has been achieved on units equipped with ESPs. Recent slip stream studies have proven up to 90% SO 2 removal and 25% NO x removal when injection is ahead of a baghouse. If dry sodium bicarbonate sorbent injection technology is used prior to a retrofitted baghouse, but after an existing ESP the sodium sulfate by-product/flyash mixture in the baghouse is over 90% Na 2 SO 4 . Simple filtration and crystallization will yield a high value 99% + pure Na 2 SO 4 for sale. In this application, no liquid discharge occurs and potentially no solids discharge, since flyash recovered from the filter is either recycled to the boiler with the coal stream or reinjected into the boiler. EPA IAPCS model Version 4 is modified to project costs for this SO 2 /NO x removal technology when couples with Na 2 SO 4 recovery. In this paper an example is used to show hardware requirements, consumables accountability, by-product recovery rates, capital costs and levelized costs

  10. The Effect of Deposit Temperature on the Catalytic SO2-to-SO3 Conversion in a Copper Flash Smelting Heat Recovery Boiler

    Science.gov (United States)

    Lehmusto, Juho; Vainio, Emil; Laurén, Tor; Lindgren, Mari

    2018-02-01

    The aim of the work was to study the catalytic role of copper flash smelter deposit in the SO2-to-SO3 conversion. In addition, the effect of process gas temperature at 548 K to 1173 K (275 °C to 900 °C) on the amount of SO3 formed was addressed both in the absence and presence of genuine copper flash smelter deposit. The SO3 conversion rate changed as a function of process gas temperature, peaking at 1023 K (750 °C). A dramatic increase in the SO2-to-SO3 conversion was observed when process dust was present, clearly indicating that process dust catalyzes the SO2-to-SO3 conversion. Based on these results, the catalytic ability of the deposit may lead to sulfuric acid dew point corrosion.

  11. OMPS/NPP PCA SO2 Total Column 1-Orbit L2 Swath 50x50km NRT

    Data.gov (United States)

    National Aeronautics and Space Administration — The OMPS-NPP L2 NM Sulfur Dioxide (SO2) Total and Tropospheric Column swath orbital collection 2 version 2.0 product contains the retrieved sulfur dioxide (SO2)...

  12. The kinetics of oxygen and SO2 consumption by red wines. What do they tell about oxidation mechanisms and about changes in wine composition?

    Science.gov (United States)

    Carrascón, Vanesa; Vallverdú-Queralt, Anna; Meudec, Emmanuelle; Sommerer, Nicolas; Fernandez-Zurbano, Purificación; Ferreira, Vicente

    2018-02-15

    This work seeks to understand the kinetics of O 2 and SO 2 consumption of air-saturated red wine as a function of its chemical composition, and to describe the chemical changes suffered during the process in relation to the kinetics. Oxygen Consumption Rates (OCRs) are faster with higher copper and epigallocatechin contents and with higher absorbance at 620nm and slower with higher levels of gallic acid and catechin terminal units in tannins. Acetaldehyde Reactive Polyphenols (ARPs) may be key elements determining OCRs. It is confirmed that SO 2 is poorly consumed in the first saturation. Phenylalanine, methionine and maybe, cysteine, seem to be consumed instead. A low SO 2 consumption is favoured by low levels of SO 2 , by a low availability of free SO 2 caused by a high anthocyanin/tannin ratio, and by a polyphenolic profile poor in epigallocatechin and rich in catechin-rich tannins. Wines consuming SO 2 efficiently consume more epigallocatechin, prodelphinidins and procyanidins. Copyright © 2017 Elsevier Ltd. All rights reserved.

  13. 40 CFR 75.16 - Special provisions for monitoring emissions from common, bypass, and multiple stacks for SO2...

    Science.gov (United States)

    2010-07-01

    ... emissions from common, bypass, and multiple stacks for SO2 emissions and heat input determinations. 75.16... emissions from common, bypass, and multiple stacks for SO2 emissions and heat input determinations. (a... maintain an SO2 continuous emission monitoring system and flow monitoring system in the duct to the common...

  14. 40 CFR 75.19 - Optional SO2, NOX, and CO2 emissions calculation for low mass emissions (LME) units.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 16 2010-07-01 2010-07-01 false Optional SO2, NOX, and CO2 emissions... § 75.19 Optional SO2, NOX, and CO2 emissions calculation for low mass emissions (LME) units. (a... input, NOX, SO2, and CO2 mass emissions, and NOX emission rate under this part. If the owner or operator...

  15. 40 CFR 75.33 - Standard missing data procedures for SO2, NOX, Hg, and flow rate.

    Science.gov (United States)

    2010-07-01

    ... SO2, NOX, Hg, and flow rate. 75.33 Section 75.33 Protection of Environment ENVIRONMENTAL PROTECTION... Procedures § 75.33 Standard missing data procedures for SO2, NOX, Hg, and flow rate. (a) Following initial...—Missing Data Procedure for SO2 CEMS, CO2 CEMS, Moisture CEMS, Hg CEMS, and Diluent (CO2 or O2) Monitors...

  16. Prospects of utilization of EB irradiation technology to augment control of SO2 and other emissions from Chilean copper smelting plants

    International Nuclear Information System (INIS)

    Villanueva, L.; Ahumada, L.; Ellison, W.; Chmielewski, A.G.; Zimek, Z.

    1997-01-01

    A technical study including testing and cost analysis for commercial use of selected processes has been conducted. Analysis, affirmation and evaluation of potential utilization of applicable SO 2 -removal process for off-gases, including electron-beam irradiation, for incrementally improving abatement of SO 2 /SO 3 emissions from existing copper smelting facilities in Chile has been carried out. Off-gases are characterized by SO 2 content higher than 3,000 ppm, a complex chemical composition and highly oxidizing conditions, along with cyclical and fluctuating generation. Laboratory tests with simulated high-SO 2 -content process were performed at Institute of Nuclear Chemistry and Technology. Test work proved the technical feasibility of removing SO 2 from (ultra-high SO 2 contents) gases by E-beam irradiation with ammonia injection. A laboratory unit with flow rate of 20 Nm 3 /h equiped with electron accelerator of 800 keV beam energy was used. Influence of different parameters on SO 2 removal efficiency, like temperature, irradiation dose, ammonia stoichiometry and water vapor content, has been established. Tests covered a high SO 2 content range, 2,000 to 10,000 ppm. A generic schematic design has been devised to system arrangement, performance and control requirements. It encompasses upgrading of in-plant ventilation to the extent required by health standards, together with gas cleaning system incorporating the EB Process. The arrangement of the facilities provides for gathering and treating off-gas from selected fugitive emission sources on a continuos basis, at the same time in-drafting a minimum amount of tramp air. An introductory dry dedusting stage, when required, uses condictioned activated carbon injection in conjunction with a fabric filter to efficiently treat raw gas and remove heavy metals, including arsenic, along with particulate matter. Main conclusion of stages of this work is that the EB Process is a simple and appropriate, cost

  17. Lyman Alpha Camera for Io's SO2 atmosphere and Europa's water plumes

    Science.gov (United States)

    McEwen, Alfred S.; Sandel, Bill; Schneider, Nick

    2014-05-01

    The Student Lyman-Alpha Mapper (SLAM) was conceived for the Io Volcano Observer (IVO) mission proposal (McEwen et al., 2014) to determine the spatial and temporal variations in Io's SO2 atmosphere by recording the H Ly-α reflection over the disk (Feldman et al., 2000; Feaga et al., 2009). SO2 absorbs at H Ly-α, thereby modulating the brightness of sunlight reflected by the surface, and measures the density of the SO2 atmosphere and its variability with volcanic activity and time of day. Recently, enhancements at the Ly-α wavelength (121.57 nm) were seen near the limb of Europa and interpreted as active water plumes ~200 km high (Roth et al., 2014). We have a preliminary design for a very simple camera to image in a single bandpass at Ly-α, analogous to a simplified version of IMAGE EUV (Sandel et al. 2000). Our goal is at least 50 resolution elements across Io and/or Europa (~75 km/pixel), ~3x better than HST STIS, to be acquired at a range where the radiation noise is below 1E-4 hits/pixel/s. This goal is achieved with a Cassegrain-like telescope with a 10-cm aperture. The wavelength selection is achieved using a simple self-filtering mirror in combination with a solar-blind photocathode. A photon-counting detector based on a sealed image intensifier preserves the poisson statistics of the incoming photon flux. The intensifier window is coated with a solar-blind photocathode material (CsI). The location of each photon event is recorded by a position-sensitive anode based on crossed delay-line or wedge-and-strip technology. The sensitivity is 0.01 counts/pixel/sec/R, sufficient to estimate SO2 column abundances ranging from 1E15 to 1E17 per cm2 in a 5 min (300 sec) exposure. Sensitivity requirements to search for and image Europa plumes may be similar. Io's Ly-α brightness of ~3 kR exceeds the 0.8 kR brightness of Europa's plume reported by Roth et al. (2014), but the plume brightness is a direct measurement rather than inferring column abundance from

  18. Reuse of Partially Sulphated CFBC Ash as an SO2 Sorbent

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Yinghai; Jia, Lufei; Anthony, E.J. [CanmetENERGY, 1 Haanel Drive, Ottawa, Ontario, K1A1M1 (Canada); Nobili, M.; Telesca, A. [Department of Environmental Engineering and Physics, University of Basilicata, Viale dell' Ateneo, Lucano 10, 85100 Potenza (Italy); Montagnaro, F. [Department of Chemistry, University of Naples ' Federico II' , Monte Sant' Angelo, 80126 Naples (Italy)

    2010-06-15

    Ashes produced from fluidized bed combustors (FBC) burning high-sulphur fuels often contain 20-30 % unreacted CaO because of the limestone added to remove SO2 in situ. This paper presents the results from experiments into reactivating partially sulphated FBC ash (both bed ash and fly ash) with liquid water, steam and sodium carbonate. The water- or steam-hydrated ashes were subsequently re-sulphated in a thermogravimetric analyzer (TGA) with simulated flue gas. The TGA results show that, while liquid water and steam successfully hydrate and reactivate the unreacted CaO in the bed ash, the treated ashes sulphated to widely different extents. Attempts to reactivate fly ash with hydration failed, although fly ash by itself is extremely reactive. A pilot-scale mini-circulating FBC (CFBC) was also used to evaluate the results of reactivation on the bed ash by hydrating with liquid water and admixtures of inorganic salt (Na2CO3) in the form of either powder or solution. When the treated ash was re-injected into the combustor with the fuel, the effect on SO2 removal efficiency was negligible if Na2CO3 was added as powder. Doping with aqueous solution resulted in enhanced SO2 removal; however, the extent was lower than the level achieved if only water hydration was employed. Increasing the amount of water (from 10% to 30%) to reactivate the ash did not improve the sulphur capture capacity in the mini-CFBC. Overall, this study suggests that the most practical way for re-use of the partially sulphated bed ash as a sulphur sorbent is reactivation by water. A proposal for utilization of the fly ash in an economically reasonable way is also discussed.

  19. Regional and Global Climate Response to Anthropogenic SO2 Emissions from China in Three Climate Models

    Science.gov (United States)

    Kasoar, M.; Voulgarakis, Apostolos; Lamarque, Jean-Francois; Shindell, Drew T.; Bellouin, Nicholas; Collins, William J.; Faluvegi, Greg; Tsigaridis, Kostas

    2016-01-01

    We use the HadGEM3-GA4, CESM1, and GISS ModelE2 climate models to investigate the global and regional aerosol burden, radiative flux, and surface temperature responses to removing anthropogenic sulfur dioxide (SO2) emissions from China. We find that the models differ by up to a factor of 6 in the simulated change in aerosol optical depth (AOD) and shortwave radiative flux over China that results from reduced sulfate aerosol, leading to a large range of magnitudes in the regional and global temperature responses. Two of the three models simulate a near-ubiquitous hemispheric warming due to the regional SO2 removal, with similarities in the local and remote pattern of response, but overall with a substantially different magnitude. The third model simulates almost no significant temperature response. We attribute the discrepancies in the response to a combination of substantial differences in the chemical conversion of SO2 to sulfate, translation of sulfate mass into AOD, cloud radiative interactions, and differences in the radiative forcing efficiency of sulfate aerosol in the models. The model with the strongest response (HadGEM3-GA4) compares best with observations of AOD regionally, however the other two models compare similarly (albeit poorly) and still disagree substantially in their simulated climate response, indicating that total AOD observations are far from sufficient to determine which model response is more plausible. Our results highlight that there remains a large uncertainty in the representation of both aerosol chemistry as well as direct and indirect aerosol radiative effects in current climate models, and reinforces that caution must be applied when interpreting the results of modelling studies of aerosol influences on climate. Model studies that implicate aerosols in climate responses should ideally explore a range of radiative forcing strengths representative of this uncertainty, in addition to thoroughly evaluating the models used against

  20. Estimation of Diseases and Mortality Attibuted to Atmospheric NO2 and SO2 Using AirQ Model in Hamadan City, Iran

    Directory of Open Access Journals (Sweden)

    Leili M

    2017-03-01

    Full Text Available Introduction: NO 2 and SO2 as gaseous air pollutants are involved in many global air accidents, and are respiratory tract irritants that can cause numerous health effcts in humans. Threfore, due to the necessity of studies in this fild and the absence of any similar study in the city of Hamadan, the aim of this study was quantifiation of health effcts attibuted to NO 2 and SO2 in Hamadan city of Iran during years 2014 and 2015. Methods: Ths was a cross-sectional study. Primarily, required criteria pollutants and meteorological data were obtained from the environmental protection agency and meteorological agency of Hamadan city, respectively. Th obtained data were validated using the World Health Organization WHO( criteria. Required statistical indices were calculated and according to baseline incidence, relative risk and exposed populations, the diffrent effcts of pollutants were assessed. Results: According to the results, the average annual concentration of NO2 and SO2 was 1.7 and 1.6 times more than the standard, respectively. With central relative risk, the estimated attibuted portion for total mortality attibuted to NO2 and SO2 was 1.74 and 0.92, respectively, which is equal to death of 51.9 and 27.3 individuals during years 2014 and 2015, respectively. Conclusion: As a result, it should be stated that most of the adverse health effcts attibuted to SO 2 and NO2 were observed in concentration ranges from 20 to 49 and 40 to 89 micrograms per cubic meter, respectively. Ths indicated that the concentration distribution of NO2 was wider than SO 2. It can also be concluded that investigated pollutants NO2 and SO2( had signifiant adverse effcts on the residents of Hamadan city and before further increase in the effcts, preventive measures should be taken by relevant authorities

  1. The Relationship Between Emissions and Economic Growth for SO2, CO2, and BC

    Science.gov (United States)

    Ru, M.; Shindell, D. T.; Tao, S.; Zhong, Q.; Seltzer, K.

    2017-12-01

    We characterize the relationship between per person emissions of SO2, CO2, and black carbon (BC) and income using a global country-level emission inventory. Pollutant emissions of SO2 and BC from the power, industry, and transportation sectors largely follow an Environmental Kuznets Curve (EKC) pattern with peak emissions at income levels between 10,000 and 100,000 USD per capita. However, for CO2, any estimated turnover income is extremely high and unlikely to be reached in the near future in power, industry, and transportation. Residential emissions show a negatively sloped linear relationship for BC, a small positive slope for CO2, and a fairly flat trajectory for SO2. For the EKC-like trajectories, "turning point" incomes for each sector and pollutant are related to technological advances and the effectiveness of emission controls. These results suggest that policy targeting technological advances and emission controls could change future pathways by affecting the "turning point" incomes. For the linear trajectories in the residential sector, we show that transitions from biomass fuel to coal in low-income countries and from coal to natural gas in middle and high-income countries, in concert with electrification levels, are the main factors governing slopes. Thus, the three pollutants show different income-emission trajectories based on the sum of the four major sectors, and the residential sector in particular has a unique relationship with income growth. As one of the first studies to analyze historical emission trajectories of BC, we find that BC differs from SO2 and CO2 because of its significantly earlier turnover in the power and industry sectors due to control policies. Total BC emissions trajectories follow a unique shape due to the combination of linearly decreasing residential emissions with EKC-like patterns in industry and transportation. We compare these trajectories to those in three Integrated Assessment Models (IAMs), GCAM, AIM, and MESSAGE

  2. Modelling of limestone injection for SO2 capture in a coal fired utility boiler

    International Nuclear Information System (INIS)

    Kovacik, G.J.; Reid, K.; McDonald, M.M.; Knill, K.

    1997-01-01

    A computer model was developed for simulating furnace sorbent injection for SO 2 capture in a full scale utility boiler using TASCFlow TM computational fluid dynamics (CFD) software. The model makes use of a computational grid of the superheater section of a tangentially fired utility boiler. The computer simulations are three dimensional so that the temperature and residence time distribution in the boiler could be realistically represented. Results of calculations of simulated sulphur capture performance of limestone injection in a typical utility boiler operation were presented

  3. A novel CO>2- and SO>2-tolerant dual phase composite membrane for oxygen separation

    DEFF Research Database (Denmark)

    Cheng, Shiyang; Søgaard, Martin; Han, Li

    2015-01-01

    A novel dual phase composite oxygen membrane (Al0.02Ga0.02Zn0.96O1.02 – Gd0.1Ce0.9O1.95-δ) was successfully prepared and tested. The membrane shows chemical stability against CO2 and SO2, and a stable oxygen permeation over 300 hours in CO2 was demonstrated. ZnO is cheap and non-toxic...... and is therefore highly advantageous compared to other common materials used for the purpose....

  4. Theoretical and experimental investigation for SO3 production in SO2-rich astrophysical environments

    International Nuclear Information System (INIS)

    Bonfim, Víctor de Souza; Pilling, Sergio; Castilho, Roberto B; Baptista, Leonardo

    2015-01-01

    This work presents the results for the irradiation of pure SO 2 sample that was condensed in a preevacuated chamber, from Laboratório de Astroquímica e Astrobiologia (LASA/UNIVAP), at low temperature (12 K) and irradiated by ionizing photons which simulate Solar photons in the vacuum ultraviolet (VUV) and soft X-rays range. The infrared spectra of irradiated sample have presented the formation of SO 3 . Experimental formation cross section was determined. Theoretical investigations were performed at Second-order Moller- Plesset perturbation theory (MP2) level and indicate the most likely SO 3 formation channels vary with the reaction supporting medium. (paper)

  5. Has patients' involvement in the decision-making process changed over time?

    NARCIS (Netherlands)

    Brink-Muinen, A. van den; Dulmen, A.M. van; Haes, H.C.J.M. de; Visser, A.P.; Schellevis, F.G.; Bensing, J.M.

    2006-01-01

    Objective: To get insight into the changes over time of patients' involvement in the decision-making process, and into the factors contributing to patients' involvement and general practitioners' (GPs) communication related to the Medical Treatment Act (MTA) Issues: information about treatment,

  6. Has patients’ involvement in the decision-making process changed over time?

    NARCIS (Netherlands)

    Brink-Muinen, A. van den; Dulmen, S.M. van; Haes, H.C.J.M. de; Visser, A.P.; Schellevis, F.G.; Bensing, J.

    2006-01-01

    Objective To get insight into the changes over time of patients’ involvement in the decision-making process, and into the factors contributing to patients’ involvement and general practitioners’ (GPs) communication related to the Medical Treatment Act (MTA) issues: information about treatment,

  7. Novel pathway of SO2 oxidation in the atmosphere: reactions with monoterpene ozonolysis intermediates and secondary organic aerosol

    Science.gov (United States)

    Ye, Jianhuai; Abbatt, Jonathan P. D.; Chan, Arthur W. H.

    2018-04-01

    Ozonolysis of monoterpenes is an important source of atmospheric biogenic secondary organic aerosol (BSOA). While enhanced BSOA formation has been associated with sulfate-rich conditions, the underlying mechanisms remain poorly understood. In this work, the interactions between SO2 and reactive intermediates from monoterpene ozonolysis were investigated under different humidity conditions (10 % vs. 50 %). Chamber experiments were conducted with ozonolysis of α-pinene or limonene in the presence of SO2. Limonene SOA formation was enhanced in the presence of SO2, while no significant changes in SOA yields were observed during α-pinene ozonolysis. Under dry conditions, SO2 primarily reacted with stabilized Criegee intermediates (sCIs) produced from ozonolysis, but at 50 % RH heterogeneous uptake of SO2 onto organic aerosol was found to be the dominant sink of SO2, likely owing to reactions between SO2 and organic peroxides. This SO2 loss mechanism to organic peroxides in SOA has not previously been identified in experimental chamber studies. Organosulfates were detected and identified using an electrospray ionization-ion mobility spectrometry-high-resolution time-of-flight mass spectrometer (ESI-IMS-TOF) when SO2 was present in the experiments. Our results demonstrate the synergistic effects between BSOA formation and SO2 oxidation through sCI chemistry and SO2 uptake onto organic aerosol and illustrate the importance of considering the chemistry of organic and sulfur-containing compounds holistically to properly account for their reactive sinks.

  8. Heterogeneous oxidation of SO2 in the radiation chemical purification of exhaust gases of thermoelectric power plants from oxides of nitrogen and sulfur

    International Nuclear Information System (INIS)

    Gerasimova, T.S.; Gerasimov, G.Ya.; Tokmacheva, I.P.

    1992-01-01

    Questions associated with numerical modeling of the heterogeneous oxidation of SO 2 in exhaust gases of thermoelectric power plants, induced by irradiation of the gas with a flux of fast electrons, are discussed. In constructing a mathematical model of the process it is considered that a phase equilibrium exists between the gas and the aerosol drops formed in the gas under the radiation influence, and the rate of the process is determined by the rate of liquid-phase oxidation of SO 2 by nitrogen dioxide in dissolved form. 7 refs., 4 figs

  9. Enhancement of removal of SO2 and NOx by powdery materials in radiation treatment of exhaust gases

    International Nuclear Information System (INIS)

    Tokunaga, Okihiro; Namba, Hideki; Suzuki, Nobutake

    1985-01-01

    We studied the effect of powdery silica on radiation removal of SO 2 and NOx from mixtures of SO 2 , NOx, water vapour, oxygen and nitrogen under irradiation by electron beams of 1.5 MeV at 120 0 C. The SO 2 and NOx concentrations decreased when powdery silica was fed without irradiation. Decrements of SO 2 and NOx concentrations were markedly enhanced when powdery silica was fed together with the irradiation. The enhancement of SO 2 - and NOx-removal is attributed to the adsorption of SO 2 and NO on the water-covered surface of powdery silica, and the effective removal of NO 2 due to the reaction with water adsorbed on the surface of powdery silica. The results obtained show that the addition of powdery silica under irradiation is an effective method of enhancing the removal of SO 2 and NOx. (author)

  10. Physicochemical properties of metal-doped activated carbons and relationship with their performance in the removal of SO2 and NO

    International Nuclear Information System (INIS)

    Gao Xiang; Liu Shaojun; Zhang Yang; Luo Zhongyang; Cen Kefa

    2011-01-01

    Research highlights: → Cu and Fe were partly reduced by carbon during preparation. → Metal-involved SO 2 removal pathways were catalytic oxidation, reaction and adsorption. → Good performances of SO 2 and NO removal depended on the metal redox pairs. - Abstract: Several metal-doped activated carbons (Fe, Co, Ni, V, Mn, Cu and Ce) were prepared and characterized. The results of N 2 adsorption-desorption, X-ray diffraction, and X-ray photoelectron spectroscopy indicated that some metals (Cu and Fe) were partly reduced by carbon during preparation. Activity tests for the removal of SO 2 and the selective catalytic reduction of NO with ammonia were carried out. Due to different physicochemical properties, different pathways for the SO 2 removal had been put out, i.e., catalytic oxidation, direct reaction and adsorption. This classification depended on the standard reduction potentials of metal redox pairs. Samples impregnated with V, Ce and Cu showed good activity for NO reduction by NH 3 , which was also ascribed to the reduction potential values of metal redox pairs. Ce seemed to be a promising alternative to V due to the higher activity in NO reduction and the nontoxic property. A metal cation which could easily convert between the two valences seemed to be crucial to the good performance of both SO 2 and NO removal, just like V and Cu.

  11. Modelling and experimentation of the SO2 remotion through a plasma out of thermal equilibrium

    International Nuclear Information System (INIS)

    Moreno S, H.; Pacheco P, M.; Pacheco S, J.; Cruz A, A.

    2005-01-01

    In spite of the measures that have taken for the decrease of the emitted pollution by mobile sources ( T oday it doesn't Circulate , implementation of catalysts in those exhaust pipes,...), the pollution in the Valley of Mexico area overcomes the limits fixed by Mexican standards several days each year. It is foreseen that for 2020 those emissions of pollutants will be increase considerably, as example we can mention to the sulfur oxides which will be increase a 48% with regard to 1998. The purpose of this work is of proposing a technique for the degradation of the sulfur dioxide (SO 2 ) that consists in introducing this gas to a plasma out of thermal equilibrium where its were formed key radicals (O, OH) for its degradation. The proposed reactor has the advantage of combining the kindness of the dielectric barrier discharge and of corona discharge, besides working to atmospheric pressure and having small dimensions. The first obtained results of the modelling of the degradation of the SO 2 in plasma as well as those experimentally obtained are presented. (Author)

  12. Improvement of the tetrachloromercurate absorption technique for measuring low atmospheric SO2 mixing ratios

    Science.gov (United States)

    Jaeschke, W.; Beltz, N.; Haunold, W.; Krischke, U.

    1997-07-01

    During the Gas-Phase Sulfur Intercomparison Experiment (GASIE) in 1994 an analytical system for measuring sulfur dioxide mixing ratios at low parts per trillion (pptv) levels was employed. It is based on the absorption of SO2 on a tetrachloromercurate(II)-impregnated filter. The subsequent analysis uses a chemiluminescence reaction by treating the resulting disulfitomercurate(II) complex with an acidic cerium sulfate solution. An improved sampling device has been introduced that increases the maximum sampling volume from 200 L to 500 L. It is also possible to determine the blank value accurately for each sample. The absorption efficiency of the sampling system is 98.7±6.4% at a nominal flow rate of 10 L/min. The calculated (3σ) detection limit is 3±1 pptv SO2. The sample solution is stable for up to 30 days, which allows the samples to be safely stored or shipped before analysis. This permits the use of a sensitive, compact, and reliable sampling system in the field with subsequent analysis under optimal conditions in the laboratory. A continuous flow chemiluminescence (CFCL) analyzer for on-line measurements is also presented. The system is based on the same chemical principles as the described filter technique.

  13. Photochemical Formation of Aerosol in Planetary Atmospheres: Photon and Water Mediated Chemistry of SO_2

    Science.gov (United States)

    Kroll, Jay A.; Donaldson, D. J.; Vaida, Veronica

    2016-06-01

    Sulfur compounds have been observed in a number of planetary atmospheres throughout our solar system. Our current understanding of sulfur chemistry explains much of what we observe in Earth's atmosphere. However, several discrepancies between modeling and observations of the Venusian atmosphere show there are still problems in our fundamental understanding of sulfur chemistry. This is of particular concern due to the important role sulfur compounds play in the formation of aerosols, which have a direct impact on planetary climates, including Earth's. We investigate the role of water complexes in the hydration of sulfur oxides and dehydration of sulfur acids and will present spectroscopic studies to document such effects. I will present recent work investigating mixtures of SO_2 and water that generate large quantities of aerosol when irradiated with solar UV light, even in the absence of traditional OH chemistry. I will discuss a proposed mechanism for the formation of sulfurous acid (H_2SO_3) and present recent experimental work that supports this proposed mechanism. Additionally, the implications that photon-induced hydration of SO_2 has for aerosol formation in the atmosphere of earth as well as other planetary atmospheres will be discussed.

  14. Aerosol formation on the flash photolysis of SO2/gas mixtures

    International Nuclear Information System (INIS)

    Fogel, L.D.; Sutherland, J.W.

    1979-01-01

    A long-lived transient absorption observed on the flash photolysis of SO 2 /gas mixtures at lambda> or =190 nm has been identified as resulting from light scattering by H 2 SO 4 aerosols. No detectable signals were monitored on photolysis at lambda> or =270 nm, indicating that the aerosol precursors originated from the promotion of SO 2 into its second singlet level and into its dissociation continuum. The SO 3 that was formed was hydrated immediately to yield H 2 SO 4 vapor in a highly supersaturated state and heteromolecular homogeneous nucleation to produce H 2 SO 4 aerosols ensued. This nucleation was quenched rapidly as the acid vapor was consumed by further nucleation, by condensation, and by vapor diffusion to the cell walls. A model was formulated in which the condensations of the H 2 SO 4 and the H 2 O vapors on the growing droplets were considered kinetically negligible and the particles grew by coagulation; simultaneously, they were lost by tranquil gravitational settling and by diffusion to the cell walls. Computer simulations demonstrated that the observed time dependence of the absorbance data (measured at a fixed wavelength) could be accounted for by this scheme. The effects of temperature, pressure, and wavelength (of the analyzing light) were also described satisfactorily by this model

  15. Possible use of electron beam treatment for removal of SO2 in off-gases from copper smelters. Preliminary tests results

    International Nuclear Information System (INIS)

    Villanueva, L.; Ahumanda, L.; Chmielewski, A.; Zimek, A.; Budka, S.; Licki, J.

    1996-01-01

    The Chilean Nuclear Energy Commission is currently performing a previous feasibility study concerning possible utilization of electron-beam process for removal of SO 2 from different types of sulfurous streams from copper smelters. First part of the project was related to verify, in a experimental line at Institute of Nuclear Chemistry and Technology, INCT, Poland, the behaviour of the process for simulated off-gases with very high SO 2 content, between 5% to 15% by volume. Tests were performed at laboratory stage and with flowrate of 5 Nm 3 /hr, using an ILU-6 electron accelerator, with the following results: High removal efficiencies of SO 2 , up to 90% were achieved for simulated off-gases containing up to 15% of SO 2 ; Required dose was in the range 5 to 8 kGy; Big influence of NH 3 stoichiometry and gas humidity on SO 2 removal efficiency; Rapid generation of sub-micron solid by-product, in great amount, that causes deposits on ducts and filtration units. This work presents the experimental results and discuss is technical projections in the field of interest. (author)

  16. Classification of processes involved in sharing individual participant data from clinical trials.

    Science.gov (United States)

    Ohmann, Christian; Canham, Steve; Banzi, Rita; Kuchinke, Wolfgang; Battaglia, Serena

    2018-01-01

    Background: In recent years, a cultural change in the handling of data from research has resulted in the strong promotion of a culture of openness and increased sharing of data. In the area of clinical trials, sharing of individual participant data involves a complex set of processes and the interaction of many actors and actions. Individual services/tools to support data sharing are available, but what is missing is a detailed, structured and comprehensive list of processes/subprocesses involved and tools/services needed. Methods : Principles and recommendations from a published data sharing consensus document are analysed in detail by a small expert group. Processes/subprocesses involved in data sharing are identified and linked to actors and possible services/tools. Definitions are adapted from the business process model and notation (BPMN) and applied in the analysis. Results: A detailed and comprehensive list of individual processes/subprocesses involved in data sharing, structured according to 9 main processes, is provided. Possible tools/services to support these processes/subprocesses are identified and grouped according to major type of support. Conclusions: The list of individual processes/subprocesses and tools/services identified is a first step towards development of a generic framework or architecture for sharing of data from clinical trials. Such a framework is strongly needed to give an overview of how various actors, research processes and services could form an interoperable system for data sharing.

  17. Response of SO2 and Particulate Air Pollution to Local and Regional Emission Controls: A Case Study in Maryland

    Science.gov (United States)

    He, Hao; Vinnikov, Konstantin Y.; Li, Can; Krotkov, Nickolay Anatoly; Jongeward, Andrew R.; Li, Zhanqing; Stehr, Jeffrey W.; Hains, Jennifer; Dickerson, RUssell R.

    2016-01-01

    This paper addresses the questions of what effect local regulations can have on pollutants with different lifetimes and how surface observations and remotely sensed data can be used to determine the impacts. We investigated the decadal trends of tropospheric sulfur dioxide (SO2) and aerosol pollution over Maryland and its surrounding states, using surface, aircraft, and satellite measurements. Aircraft measurements indicated fewer isolated SO2 plumes observed in summers, a 40 decrease of column SO2, and a 20 decrease of atmospheric optical depth (AOD) over Maryland after the implementation of local regulations on sulfur emissions from power plants (90 reduction from 2010). Surface observations of SO2 and particulate matter (PM) concentrations in Maryland show similar trends. OMI SO2 and MODIS AOD observations were used to investigate the column contents of air pollutants over the eastern U.S.; these indicate decreasing trends in column SO2 (60 decrease) and AOD (20 decrease). The decrease of upwind SO2 emissions also reduced aerosol loadings over the downwind Atlantic Ocean near the coast by 20, while indiscernible changes of the SO2 column were observed. A step change of SO2 emissions in Maryland starting in 20092010 had an immediate and profound benefit in terms of local surface SO2 concentrations but a modest impact on aerosol pollution, indicating that short-lived pollutants are effectively controlled locally, while long-lived pollutants require regional measures.

  18. Comparison and evaluation of anthropogenic emissions of SO2 and NOx over China

    Directory of Open Access Journals (Sweden)

    M. Li

    2018-03-01

    Full Text Available Bottom-up emission inventories provide primary understanding of sources of air pollution and essential input of chemical transport models. Focusing on SO2 and NOx, we conducted a comprehensive evaluation of two widely used anthropogenic emission inventories over China, ECLIPSE and MIX, to explore the potential sources of uncertainties and find clues to improve emission inventories. We first compared the activity rates and emission factors used in two inventories and investigated the reasons of differences and the impacts on emission estimates. We found that SO2 emission estimates are consistent between two inventories (with 1 % differences, while NOx emissions in ECLIPSE's estimates are 16 % lower than those of MIX. The FGD (flue-gas desulfurization device penetration rate and removal efficiency, LNB (low-NOx burner application rate and abatement efficiency in power plants, emission factors of industrial boilers and various vehicle types, and vehicle fleet need further verification. Diesel consumptions are quite uncertain in current inventories. Discrepancies at the sectorial and provincial levels are much higher than those of the national total. We then examined the impacts of different inventories on model performance by using the nested GEOS-Chem model. We finally derived top-down emissions by using the retrieved columns from the Ozone Monitoring Instrument (OMI compared with the bottom-up estimates. High correlations were observed for SO2 between model results and OMI columns. For NOx, negative biases in bottom-up gridded emission inventories (−21 % for MIX, −39 % for ECLIPSE were found compared to the satellite-based emissions. The emission trends from 2005 to 2010 estimated by two inventories were both consistent with satellite observations. The inventories appear to be fit for evaluation of the policies at an aggregated or national level; more work is needed in specific areas in order to improve the accuracy and robustness of

  19. Comparison and evaluation of anthropogenic emissions of SO2 and NOx over China

    Science.gov (United States)

    Li, Meng; Klimont, Zbigniew; Zhang, Qiang; Martin, Randall V.; Zheng, Bo; Heyes, Chris; Cofala, Janusz; Zhang, Yuxuan; He, Kebin

    2018-03-01

    Bottom-up emission inventories provide primary understanding of sources of air pollution and essential input of chemical transport models. Focusing on SO2 and NOx, we conducted a comprehensive evaluation of two widely used anthropogenic emission inventories over China, ECLIPSE and MIX, to explore the potential sources of uncertainties and find clues to improve emission inventories. We first compared the activity rates and emission factors used in two inventories and investigated the reasons of differences and the impacts on emission estimates. We found that SO2 emission estimates are consistent between two inventories (with 1 % differences), while NOx emissions in ECLIPSE's estimates are 16 % lower than those of MIX. The FGD (flue-gas desulfurization) device penetration rate and removal efficiency, LNB (low-NOx burner) application rate and abatement efficiency in power plants, emission factors of industrial boilers and various vehicle types, and vehicle fleet need further verification. Diesel consumptions are quite uncertain in current inventories. Discrepancies at the sectorial and provincial levels are much higher than those of the national total. We then examined the impacts of different inventories on model performance by using the nested GEOS-Chem model. We finally derived top-down emissions by using the retrieved columns from the Ozone Monitoring Instrument (OMI) compared with the bottom-up estimates. High correlations were observed for SO2 between model results and OMI columns. For NOx, negative biases in bottom-up gridded emission inventories (-21 % for MIX, -39 % for ECLIPSE) were found compared to the satellite-based emissions. The emission trends from 2005 to 2010 estimated by two inventories were both consistent with satellite observations. The inventories appear to be fit for evaluation of the policies at an aggregated or national level; more work is needed in specific areas in order to improve the accuracy and robustness of outcomes at finer spatial

  20. Intercomparison of Metop-A SO2 measure- ments during the 2010- 2011 Icelandic eruptions

    Directory of Open Access Journals (Sweden)

    Maria Elissavet Koukouli

    2015-03-01

    Full Text Available The European Space Agency project Satellite Monitoring of Ash and Sulphur Dioxide for the mitigation of Avi­ ation Hazards, was introduced after the eruption of the Icelandic volcano Eyjafjallajökull in the spring of 2010 to facilitate the development of an optimal End­to­End System for Volcanic Ash Plume Monitoring and Predic­ tion. The Eyjafjallajökull plume drifted towards Europe and caused major disruptions of European air traffic for several weeks affecting the everyday life of millions of people. The limitations in volcanic plume monitoring and prediction capabilities gave birth to this observational system which is based on comprehensive satellite­derived ash plume and sulphur dioxide [SO2] level estimates, as well as a widespread validation using supplementary satellite, aircraft and ground­based measurements. Inter­comparison of the volcanic total SO2 column and plume height observed by GOME­2/Metop­A and IASI/Metop­A are shown before, during and after the Eyjaf­ jallajökull 2010 eruptions as well as for the 2011 Grímsvötn eruption. Co­located ground­based Brewer Spectro­ photometer data extracted from the World Ozone and Ultraviolet Radiation Data Centre for de Bilt, the Nether­ lands, are also compared to the different satellite estimates. Promising agreement is found for the two different types of instrument for the SO2 columns with linear regression coefficients ranging around from 0.64 when comparing the different instruments and 0.85 when comparing the two different IASI algorithms. The agree­ ment for the plume height is lower, possibly due to the major differences between the height retrieval part of the GOME2 and IASI algorithms. The comparisons with the Brewer ground­based station in de Bilt, The Nether­ lands show good qualitative agreement for the peak of the event however stronger eruptive signals are required for a longer quantitative comparison. 

  1. Matrix elements of a hyperbolic vector operator under SO(2,1)

    International Nuclear Information System (INIS)

    Zettili, N.; Boukahil, A.

    2003-01-01

    We deal here with the use of Wigner–Eckart type arguments to calculate the matrix elements of a hyperbolic vector operator V-vector by expressing them in terms of reduced matrix elements. In particular, we focus on calculating the matrix elements of this vector operator within the basis of the hyperbolic angular momentum T-vector whose components T-vector 1 , T-vector 2 , T-vector 3 satisfy an SO(2,1) Lie algebra. We show that the commutation rules between the components of V-vector and T-vector can be inferred from the algebra of ordinary angular momentum. We then show that, by analogy to the Wigner–Eckart theorem, we can calculate the matrix elements of V-vector within a representation where T-vector 2 and T-vector 3 are jointly diagonal. (author)

  2. High-Temperature Release of SO2 from Calcined Cement Raw Materials

    DEFF Research Database (Denmark)

    Nielsen, Anders Rooma; Larsen, Morten B.; Glarborg, Peter

    2011-01-01

    During combustion of alternative fuels in the material inlet end of cement rotary kilns, local reducing conditions may occur and cause reductive decomposition of sulfates from calcined cement raw materials. Decomposition of sulfates is problematic because it increases the gas-phase SO2...... concentration, which may cause deposit formation in the kiln system. In this study, the release of sulfur from calcined cement raw materials under both oxidizing and reducing conditions is investigated. The investigations include thermodynamic equilibrium calculations in the temperature interval of 800–1500 °C...... and experiments in a tube furnace reactor in the temperature interval of 900–1100 °C. The investigated conditions resemble actual conditions in the material inlet end of cement rotary kilns. It was found that the sulfates CaSO4, K2SO4, and Na2SO4 were all stable under oxidizing conditions but began to decompose...

  3. Research progress of SO2 removal from flue gas by functionalized ionic liquids

    Directory of Open Access Journals (Sweden)

    Xinle SHI

    2017-02-01

    Full Text Available Functionalized ionic liquids are receiving increasing attention in the field of flue gas desulfurization due to its unique physical and chemical properties. Research progress on the field of SO2 removal by ionic liquids (ILs including guanidinium-based, amines-based and ether-based ILs is summarized. Industrial application of polymerization ILs and loaded ILs to desulfurization is reviewed. Relevant suggestions on industrial application of ionic liquids based on fundamental research are put forward. The first thing is to develop functional ionic liquid for desulfurization,and thus investigate and propose its desulfurization mechanism and model; the second is to carry out the research work on immobilized ionic liquid, and explore its recycling properties, thus prolonging its service life.

  4. Success of lime additives for controlling SO2 releases from fluidized bed combustion units

    International Nuclear Information System (INIS)

    Muezzinoglu, A.; Bayram, A.; Odabasi, M.

    1995-01-01

    Purpose of this work was to study the desulfurization efficiencies of dry additives on the fluidized bed reactors fired with low quality lignites. In these tests selected initial SO 2 levels were in the order of 1000 ppm or less in the flue gases. Lime addition for desulfurization may either be made by mixing with the fuel or by injection into the combustion reactor. In fluidized bed combustion systems both methods are physically possible. In the fluidized combustion systems a third method of addition is also possible this, is by mixing dry additives with fluidizer sand. In this third method additives create a fluidizer effect as well as reacting with the sulfur oxides being formed during the combustion of fuel

  5. Recent advances in ground-based ultraviolet remote sensing of volcanic SO2 fluxes

    Directory of Open Access Journals (Sweden)

    Euripides P. Kantzas

    2011-06-01

    Full Text Available Measurements of volcanic SO2 emission rates have been the mainstay of remote-sensing volcanic gas geochemistry for almost four decades, and they have contributed significantly to our understanding of volcanic systems and their impact upon the atmosphere. The last ten years have brought step-change improvements in the instrumentation applied to these observations, which began with the application of miniature ultraviolet spectrometers that were deployed in scanning and traverse configurations, with differential optical absorption spectroscopy evaluation routines. This study catalogs the more recent empirical developments, including: ultraviolet cameras; wide-angle field-of-view differential optical absorption spectroscopy systems; advances in scanning operations, including tomography; and improved understanding of errors, in particular concerning radiative transfer. Furthermore, the outcomes of field deployments of sensors during the last decade are documented, with respect to improving our understanding of volcanic dynamics and degassing into the atmosphere.

  6. Potential impacts of NOx and SO2 constraints on CIPS operations

    International Nuclear Information System (INIS)

    Almasque, J.; Montgomery, D.; Le, K.; Boyle, R.; Nguyen, M.; Orndoff, D.

    1994-01-01

    To meet the Clean Air Act requirements, CIPS will need to spend around $30 million to curtail its SO 2 and NO x emissions by 40 percent. A key challenge facing CIPS management is to determine an emission compliance strategy that minimizes the total system production costs while maintaining a reasonable safety margin and back-up plan. CIPS is currently testing tools to perform emission-constrained unit commitment and economic dispatch. This ''soft'' option provides a back-up measure, should unforeseen occurrences take place or newly installed NO x reduction equipment fail to perform as expected. Algorithm development, software modification, procedural changes, and data collection required to implement emission-constrained dispatch will need to be in place by January, 1995. By taking advantage of ''soft'' methods, such as emission-constrained dispatch, emission trading, and operator training, CIPS hopes to reduce its emission-related capital expenditures by 5--20 percent

  7. Involving patients in health technology funding decisions: stakeholder perspectives on processes used in Australia.

    Science.gov (United States)

    Lopes, Edilene; Street, Jackie; Carter, Drew; Merlin, Tracy

    2016-04-01

    Governments use a variety of processes to incorporate public perspectives into policymaking, but few studies have evaluated these processes from participants' point of view. The objective of this study was twofold: to understand the perspectives of selected stakeholders with regard to involvement processes used by Australian Advisory Committees to engage the public and patients; and to identify barriers and facilitators to participation. Twelve semi-structured interviews were conducted with representatives of different stakeholder groups involved in health technology funding decisions in Australia. Data were collected and analysed using a theoretical framework created by Rowe and Frewer, but adapted to more fully acknowledge issues of power and influence. Stakeholder groups disagreed as to what constitutes effective and inclusive patient involvement. Barriers reported by interviewees included poor communication, a lack of transparency, unworkable deadlines, and inadequate representativeness. Also described were problems associated with defining the task for patients and their advocates and with the timing of patient input in the decision-making process. Interviewees suggested that patient participation could be improved by increasing the number of patient organizations engaged in processes and including those organizations at different stages of decision making, especially earlier. The different evaluations made by stakeholder groups appear to be underpinned by contrasting conceptions of public involvement and its value, in line with Graham Martin's work which distinguishes between 'technocratic' and 'democratic' public involvement. Understanding stakeholders' perspectives and the contrasting conceptions of public involvement could foster future agreement on which processes should be used to involve the public in decision making. © 2015 John Wiley & Sons Ltd.

  8. A Fast and Sensitive New Satellite SO2 Retrieval Algorithm based on Principal Component Analysis: Application to the Ozone Monitoring Instrument

    Science.gov (United States)

    Li, Can; Joiner, Joanna; Krotkov, A.; Bhartia, Pawan K.

    2013-01-01

    We describe a new algorithm to retrieve SO2 from satellite-measured hyperspectral radiances. We employ the principal component analysis technique in regions with no significant SO2 to capture radiance variability caused by both physical processes (e.g., Rayleigh and Raman scattering and ozone absorption) and measurement artifacts. We use the resulting principal components and SO2 Jacobians calculated with a radiative transfer model to directly estimate SO2 vertical column density in one step. Application to the Ozone Monitoring Instrument (OMI) radiance spectra in 310.5-340 nm demonstrates that this approach can greatly reduce biases in the operational OMI product and decrease the noise by a factor of 2, providing greater sensitivity to anthropogenic emissions. The new algorithm is fast, eliminates the need for instrument-specific radiance correction schemes, and can be easily adapted to other sensors. These attributes make it a promising technique for producing longterm, consistent SO2 records for air quality and climate research.

  9. THE EFFECT OF IRRADIATION DOSE AND AMMONIA CONCENTRATION ON THE APPLICATION OF ELECTRON BEAM FOR TREATMENT GASES POLLUTION OF SO2AND NOX

    Directory of Open Access Journals (Sweden)

    Erizal Erizal

    2010-06-01

    Full Text Available The application of electron beam for treatment gases pollution of SO2 and NOx has been studied.  The simulated SO2 and NOx gases stream produced from diesel fuel burning boiler were flown into electron beam chamber. Irradiation was conducted using 1000 keV electron beam machine at the dose up to 8.8 kGy, while   water vapour and the ammonia gas with variation concentration flew into the system during irradiation. The concentrations of the gases change were observed during processes. After evaluation, it was found that by increasing irradiation dose, the concentration of SO2 and NOx gases removal increases.  The efficiency of gases removal may reach 98 % for SO2 and 88 % for NOX at a dose of 8.8 kGy. By increasing ammonia concentration, the efficiency gas removal increases. Besides, by-products from the irradiation yield were sulfate and nitrate salt compound which are possible to be used as a fertilizer.      Keywords: radiation, electron beam, gas pollution, SO2, NOx, ammonia

  10. NO and H2O2 contribute to SO2 toxicity via Ca2+ signaling in Vicia faba guard cells.

    Science.gov (United States)

    Yi, Min; Bai, Heli; Xue, Meizhao; Yi, Huilan

    2017-04-01

    NO and H 2 O 2 have been implicated as important signals in biotic and abiotic stress responses of plants to the environment. Previously, we have shown that SO 2 exposure increased the levels of NO and H 2 O 2 in plant cells. We hypothesize that, as signaling molecules, NO and H 2 O 2 mediate SO 2 -caused toxicity. In this paper, we show that SO 2 hydrates caused guard cell death in a concentration-dependent manner in the concentration range of 0.25 to 6 mmol L -1 , which was associated with elevation of intracellular NO, H 2 O 2 , and Ca 2+ levels in Vicia faba guard cells. NO donor SNP enhanced SO 2 toxicity, while NO scavenger c-PTIO and NO synthesis inhibitors L-NAME and tungstate significantly prevented SO 2 toxicity. ROS scavenger ascorbic acid (AsA) and catalase (CAT), Ca 2+ chelating agent EGTA, and Ca 2+ channel inhibitor LaCl 3 also markedly blocked SO 2 toxicity. In addition, both c-PTIO and AsA could completely block SO 2 -induced elevation of intracellular Ca 2+ level. Moreover, c-PTIO efficiently blocked SO 2 -induced H 2 O 2 elevation, and AsA significantly blocked SO 2 -induced NO elevation. These results indicate that extra NO and H 2 O 2 are produced and accumulated in SO 2 -treated guard cells, which further activate Ca 2+ signaling to mediate SO 2 toxicity. Our findings suggest that both NO and H 2 O 2 contribute to SO 2 toxicity via Ca 2+ signaling.

  11. 40 CFR 51.125 - Emissions reporting requirements for SIP revisions relating to budgets for SO2 and NOX emissions.

    Science.gov (United States)

    2010-07-01

    ... SIP revisions relating to budgets for SO2 and NOX emissions. 51.125 Section 51.125 Protection of... SIP revisions relating to budgets for SO2 and NOX emissions. (a) For its transport SIP revision under § 51.123 and/or 51.124, each State must submit to EPA SO2 and/or NOX emissions data as described in...

  12. Effect of flue gas composition on deposit induced high temperature corrosion under laboratory conditions mimicking biomass firing. Part II: Exposures in SO2 containing atmospheres

    DEFF Research Database (Denmark)

    Okoro, Sunday Chukwudi; Kiamehr, Saeed; Montgomery, Melanie

    2017-01-01

    SO2. Scanning electron microscopy (SEM), energy dispersive X-rayspectroscopy (EDS) and X-ray diffraction (XRD) techniques werecomplimentarily applied to characterize the resulting corrosion products. Apartially molten K2SO4-layer formed on KCl coated specimens, and corrosionresulted in localized......In biomass fired power plants, the fast corrosion of superheaters is facilitatedby the presence of corrosive flue gas species, for example, SO2, which arereleased during combustion. To understand the role of the gas species on thecorrosion process, comparative laboratory exposures of deposit (KCl......)-coatedand deposit-free austenitic stainless steel (TP 347H FG) samples to gas mixturescontaining SO2 was carried out, under conditions relevant to biomass-firing.Exposures were conducted isothermally at 560 8C for 72 h, in oxidizingsulphidizing,and oxidizing-sulphidizing-chlorinating gas mixtures containing60 ppmv...

  13. The purchase decision process and involvement of the elderly regarding nonprescription products.

    Science.gov (United States)

    Reisenwitz, T H; Wimbish, G J

    1997-01-01

    The elderly or senior citizen is a large and growing market segment that purchases a disproportionate amount of health care products, particularly nonprescription products. This study attempts to examine the elderly's level of involvement (high versus low) and their purchase decision process regarding nonprescription or over-the-counter (OTC) products. Frequencies and percentages are calculated to indicate level of involvement as well as purchase decision behavior. Previous research is critiqued and managerial implications are discussed.

  14. Stakeholder involvement in stages of a participatory process illustrated in interior design cases

    DEFF Research Database (Denmark)

    Vink, Peter; van Rhijn, Gu; Seim, Rikke

    2008-01-01

    In a previous study (Vink et al., 2008) an overview was made of the involvement of different stakeholders in a participatory design process. In this paper this overview was used to describe four participatory design cases focused on improvising productivity, health, and comfort by interior design....... It appeared that this overview is useful to describe the involvement in participatory interior design projects. However, it can only serve as an initial benchmark as much is dependent on the specific case at hand....

  15. STAKEHOLDER INVOLVEMENT IN THE HEALTH TECHNOLOGY ASSESSMENT PROCESS IN LATIN AMERICA.

    Science.gov (United States)

    Pichon-Riviere, Andres; Soto, Natalie; Augustovski, Federico; Sampietro-Colom, Laura

    2018-06-11

    Latin American countries are taking important steps to expand and strengthen universal health coverage, and health technology assessment (HTA) has an increasingly prominent role in this process. Participation of all relevant stakeholders has become a priority in this effort. Key issues in this area were discussed during the 2017 Latin American Health Technology Assessment International (HTAi) Policy Forum. The Forum included forty-one participants from Latin American HTA agencies; public, social security, and private insurance sectors; and the pharmaceutical and medical device industry. A background paper and presentations by invited experts and Forum members supported discussions. This study presents a summary of these discussions. Stakeholder involvement in HTA remains inconsistently implemented in the region and few countries have established formal processes. Participants agreed that stakeholder involvement is key to improve the HTA process, but the form and timing of such improvements must be adapted to local contexts. The legitimization of both HTA and decision-making processes was identified as one of the main reasons to promote stakeholder involvement; but to be successful, the entire system of assessment and decision making must be properly staffed and organized, and certain basic conditions must be met, including transparency in the HTA process and a clear link between HTA and decision making. Participants suggested a need for establishing clear rules of participation in HTA that would protect HTA producers and decision makers from potentially distorting external influences. Such rules and mechanisms could help foster trust and credibility among stakeholders, supporting actual involvement in HTA processes.

  16. An automated SO2 camera system for continuous, real-time monitoring of gas emissions from Kīlauea Volcano's summit Overlook Crater

    Science.gov (United States)

    Kern, Christoph; Sutton, Jeff; Elias, Tamar; Lee, Robert Lopaka; Kamibayashi, Kevan P.; Antolik, Loren; Werner, Cynthia A.

    2015-01-01

    SO2 camera systems allow rapid two-dimensional imaging of sulfur dioxide (SO2) emitted from volcanic vents. Here, we describe the development of an SO2 camera system specifically designed for semi-permanent field installation and continuous use. The integration of innovative but largely “off-the-shelf” components allowed us to assemble a robust and highly customizable instrument capable of continuous, long-term deployment at Kīlauea Volcano's summit Overlook Crater. Recorded imagery is telemetered to the USGS Hawaiian Volcano Observatory (HVO) where a novel automatic retrieval algorithm derives SO2 column densities and emission rates in real-time. Imagery and corresponding emission rates displayed in the HVO operations center and on the internal observatory website provide HVO staff with useful information for assessing the volcano's current activity. The ever-growing archive of continuous imagery and high-resolution emission rates in combination with continuous data from other monitoring techniques provides insight into shallow volcanic processes occurring at the Overlook Crater. An exemplary dataset from September 2013 is discussed in which a variation in the efficiency of shallow circulation and convection, the processes that transport volatile-rich magma to the surface of the summit lava lake, appears to have caused two distinctly different phases of lake activity and degassing. This first successful deployment of an SO2 camera for continuous, real-time volcano monitoring shows how this versatile technique might soon be adapted and applied to monitor SO2 degassing at other volcanoes around the world.

  17. Efficient absorption of SO_2 with low-partial pressures by environmentally benign functional deep eutectic solvents

    International Nuclear Information System (INIS)

    Zhang, Kai; Ren, Shuhang; Hou, Yucui; Wu, Weize

    2017-01-01

    Graphical abstract: Environmentally benign deep eutectic solvents (DESs) based on betaine or L-carnitine with ethylene glycol were designed with a function and used to efficiently capture SO_2 with low partial pressures. - Highlights: • Deep eutectic solvents (DESs) were designed with a function to absorb low-conc. SO_2. • Betaine(Bet) and L-carnitine(L-car) with a functional group were used as H-bond acceptor. • Bet + ethylene glycol (EG) DES and L-car + EG DES are environmentally benign. • L-car + EG DES can absorb 0.644 mol SO_2 per mole L-car (0.37% SO_2). • L-car + EG DES is a promising absorbent for SO_2 capture. - Abstract: Sulfur dioxide (SO_2) emitted from the burning of fossil fuels is one of the main air contaminants. In this work, we found that environmentally benign solvents, deep eutectic solvents (DESs) could be designed with a function to absorb low-partial pressure SO_2 from simulated flue gas. Two kinds of biodegradable functional DESs based on betaine (Bet) and L-carnitine (L-car) as hydrogen bond accepters (HBA) and ethylene glycol (EG) as a hydrogen bond donor (HBD) were prepared with mole ratios of HBA to HBD from 1:3 to 1:5, and they were investigated to absorb SO_2 with different partial pressures at various temperatures. The results showed that the two DESs could absorb low-partial pressure SO_2 efficiently. SO_2 absorption capacities of the DESs with HBA/HBD mole ratio of 1:3 were 0.332 mol SO_2/mol HBA for Bet + EG DES and 0.820 mol SO_2/mol HBA for L-car + EG DES at 40 °C with a SO_2 partial pressure of 0.02 atm. In addition, the regeneration experiments demonstrated that the absorption capacities of DESs did not change after five absorption and desorption cycles. Furthermore, the absorption mechanism of SO_2 by DESs was studied by FT-IR, "1H NMR and "1"3C NMR spectra. It was found that there are strong acid–base interactions between SO_2 and −COO"− on HBA.

  18. Volcanogenic SO2, a natural pollutant: Measurements, modeling and hazard assessment at Vulcano Island (Aeolian Archipelago, Italy).

    Science.gov (United States)

    Granieri, Domenico; Vita, Fabio; Inguaggiato, Salvatore

    2017-12-01

    Sulfur dioxide (SO 2 ) is a major component of magmatic gas discharges. Once emitted in the atmosphere it can affect the air and land environment at different spatial and temporal scales, with harmful effects on human health and plant communities. We used a dense dataset of continuous SO 2 flux and meteorological measurements collected at Vulcano over an 8-year period spanning from May 2008 to February 2016 to model air SO 2 concentrations over the island. To this end, we adopted the DISGAS (DISpersion of GAS) numerical code coupled with the Diagnostic Wind Model (DWM). SO 2 concentrations in air were determined for three different SO 2 emission rates: a reference SO 2 flux of ∼18 t/d (the median of more than 800 measurements), an enhanced SO 2 flux of 40 t/d (average of all measurements plus 1 σ), and a maximum SO 2 flux of 106 t/d (maximum value measured in the investigated period). Maximum SO 2 concentrations in air were estimated at the crater, near the high-T fumarole field that is the source of the gas, and ranged from 2000 ppb to ∼24,000 ppb for the reference flux, from 2000 ppb to 51,000 ppb for the enhanced flux and from 5000 ppb to 136,000 ppb for the maximum flux, with peak values in limited areas at the bottom of the crater. These concentrations pose a hazard for people visiting the crater, for sensitive individuals in particular. Based on estimated SO 2 concentrations in air, we also consider the phytotoxic effects of SO 2 on local vegetation. Copyright © 2017 Elsevier Ltd. All rights reserved.

  19. Chronic SO2 inhalation above environmental standard impairs neuronal behavior and represses glutamate receptor gene expression and memory-related kinase activation via neuroinflammation in rats.

    Science.gov (United States)

    Yao, Gaoyi; Yue, Huifeng; Yun, Yang; Sang, Nan

    2015-02-01

    Sulfur dioxide (SO2), as a ubiquitous air pollutant implicated in the genesis of pulmonary disease, is now being considered to be involved in neurotoxicity and increased risk for hospitalization of brain disorders. However, comparatively little is known about the impact of chronically SO2 inhalation on neuronal function. In the present study, by exposing male Wistar rats to SO2 at 3.50 and 7.00 mg/m(3) (approximately 1225 and 2450 ppb, 4.08-8.16 (24h average concentration) times higher than the EPA standard for environmental air concentrations) or filtered air for 90 days, we investigated the impact of chronic SO2 inhalation on performance in Morris water maze, and probed the accompanying neurobiological effects, including activity-regulated cytoskeletal associated gene (Arc) and glutamate receptor gene expression, memory-related kinase level and inflammatory cytokine release in the hippocampus. Here, we found that SO2 exposure reduced the number of target zone crossings and time spent in the target quadrant during the test session in the spatial memory retention of the Morris water maze. Following the neuro-functional abnormality, we detected that SO2 inhalation reduced the expression of Arc and glutamate receptor subunits (GluR1, GluR2, NR1, NR2A, and NR2B) with a concentration-dependent property in comparison to controls. Additionally, the expression of memory kinases was attenuated statistically in the animals receiving the higher concentration, including protein kinase A (PKA), protein kinase C (PKC) and calcium/calmodulin-dependent protein kinaseIIα (CaMKIIα). And the inflammatory cytokine release was increased in rats exposed to SO2. Taken together, our results suggest that long-term exposure to SO2 air pollution at concentrations above the environmental standard in rats impaired spatial learning and memory, and indicate a close link between the neurobiological changes highlighted in the brain and the behavioral disturbances. Copyright © 2014 Elsevier Inc

  20. A voice from the high wire: Public involvement in a co-operative siting process

    International Nuclear Information System (INIS)

    Oates, D.J.L.

    1995-01-01

    The author is a public consultation and communications consultant to the Siting Task Force (STF), Low level Radioactive Waste Management. The STF is a Canadian government-appointed yet independent body implementing a voluntary, co-operative siting process for a long term storage or disposal facility for 1 million cubic metres of LLRW. The presentation will document the experiences of and lessons learned by the author during her role developing and implementing a public involvement program for the process. The Co-operative Siting Process is a new approach to siting controversial facilities. It is based on the belief that communities should accept such a facility in their backyard and not be forced against their will on technical or political grounds. A formal 'ground rules-up-front' process was developed and is now being carried out, with completion slated for April, 1995. Putting these rules and theories into practice has resulted in significant changes being made to the work plan for technical activities, and in a sober second look at the intricacies involved in planning and carrying out a thorough and efficient public involvement program that remain practical and cost-effective. There is a delicate balancing act between meaningful public participation that lays the foundation for trust, confidence and consensus, and public involvement that can result in the process being side-tracked and legitimate solutions and technical activities becoming mired in political and personal agendas

  1. Dynamics and Evolution of SO 2 Gas Condensation around Prometheus-like Volcanic Plumes on Io as Seen by the Near Infrared Mapping Spectrometer

    Science.gov (United States)

    Douté, Sylvain; Lopes, Rosaly; Kamp, Lucas W.; Carlson, Robert; Schmitt, Bernard; Galileo NIMS Team

    2002-08-01

    We analyze a series of spectral image cubes acquired by the Galileo Near Infrared Mapping Spectrometer (NIMS) over the Prometheus region of Io. We use SO 2 frost, a volatile compound ubiquitous on the surface, as a tracer to understand various thermodynamic and volcanic processes acting in this equatorial region. Here we develop a new method to derive, from the 12-wavelength NIMS products, the distribution and physical properties of solid SO 2. This method is based on the inversion of a bidirectional reflectance model on two observed spectral ratios sensitive to (1) the areal abundance of SO 2 and (2) its mean grain size. As a result, reliable and consistent maps of SO 2 abundance and granularity are obtained which can be correlated to distinguish four different physical units. The distribution of these SO 2 units indicates zones of condensation, metamorphism, and sublimation linked with the thermodynamic and volcanic processes of interest. Our maps depict equatorial plains undisturbed by any kind of vigorous volcanic activity over 35-40% of their surface. Elsewhere, 10-20% of the equatorial plains display abnormally low frost coverage which may imply the recent presence of positive thermal anomalies with temperatures in the range 110-200 K. Hot-spots such as Prometheus, Culann, Surya, and Tupan (to mention the most persistent) emit a great variety of gases, some of which will condense at Io's surface near their source regions. Associated fields of freshly condensed SO 2 are easily observed, and deposits of more refractory compounds with higher (e.g., S 8) or lower (e.g., NaCl) molecular weight must also be present (although their exact nature is unknown). Three different mechanisms of emission are proposed for the volatile compounds and supported by the distribution maps. These are (a) the interaction between flowing lava and preexisting volatile deposits on the surface, (b) direct degassing from the lava, an d (c) the eruption of a liquid aquifer from underground

  2. Impacts of some meteorological parameters on the SO2 concentrations in the City of Obrenovac, Serbia

    Directory of Open Access Journals (Sweden)

    SNEŽANA S. NENADOVIĆ

    2010-05-01

    Full Text Available In this paper, the impacts of some meteorological parameters on the SO2 concentrations in the City of Obrenovac are presented. The City of Obrenovac is located in the north-west part of Serbia on the banks of the River Sava. The observed source emission, the power plants TENT A and B are situated on the bank of the Sava River in the vicinity of Obrenovac. During the period from January to November 2006, the concentrations of sulfur dioxide in the air at 4 monitoring sites in Obrenovac were measured. It was noticed that the maximal measured daily concentrations of sulfur dioxide ranged from 1 μg m-3 (16th November, 2006 to 98 μg m-3 (29th January 2006 and lie under the maximal allowed concentration value according to the Serbian Law on Environmental Protection. The measured sulfur dioxide concentrations mostly showed characteristics usual for a daily acidification sulfur dioxide cycle, excluding the specificities influenced by the measuring site itself. Sulfur dioxide transport was recorded at increased wind speeds, primarily from the southeast direction. Based on the impact of meteorological parameters on the sulfur dioxide concentration, a validation of the monitoring sites was also performed from the aspect of their representivity.

  3. In-cloud oxidation of SO2 as deduced from trace elements in aerosol and precipitation

    International Nuclear Information System (INIS)

    Heaton, R.; Rahn, K.A.

    1985-01-01

    During the past year, the authors have developed and begun to apply a sampling and analytical technique for precipitation which can measure nearly as many elements (30-40) as in the parent aerosol. Rain is collected in a polyethylene bag mounted directly under a simple polyethylene funnel. Typically, up to 500 ml are accumulated; sampling begins only after the rain has started. Snow is scooped into the same kind of bag during or shortly after the event; up to 500 ml are accumulated by repeated sampling and melting in the laboratory. The bags are sealed, frozen overnight, then opened and freeze-dried until all the ice has disappeared. The bag and its contents are then analyzed by instrumental neutron activation at the Rhode Island Nuclear Science Center. Sulfate is determined from a small aliquot of the precipitation removed before it is frozen. For comparison, aerosol samples taken before, during, and after the event are analyzed similarly. The principal goal of this research is to develop procedures for applying the University of Rhode Island's regional elemental tracer system, originally to use the patter of trace elements in precipitation to determine the fraction of the sulfate which has been produced by in-cloud oxidation of SO 2 , as opposed to direct scavenging of sulfate from aerosol

  4. Anthropogenic SO2/NOx committee summary of current status--annual inventory

    International Nuclear Information System (INIS)

    Benkovitz, C.M.

    1992-06-01

    At the First GEIA Workshop on Global Emissions Inventories, held in Baltimore, MD on December 1--2, 1991, data on anthropogenic emissions of sulfur and nitrogen developed by Dignon (1992) were selected to form the basis for the GEIA SO 2 and NO x annual inventories. The Dignon data include emissions from fuel combustion only and currently extend to 1980. The methodology used was detailed in Dignon and Hameed (1985) and consists of statistical regression models based on available emissions data from the U.S and some other member countries of the Organization of Economic Cooperation and Development (OECD), which includes Australia, Canada, Japan and western European countries. Control regulations are incorporated via the use of different statistical parameter The grid definition from these inventories was also adopted for the GEIA grid: origin at 180 degree W, 90 degree S, 1 degree x 1 degree resolution (i.e., 360 cells in the longitude direction, 180 cells in the latitude direction). To upgrade the basic GEIA inventories, data for the different geographic regions being solicited from researchers located within these areas. This paper contains the upgrades which have been accomplished to date

  5. Aerosol particle charger and an SO2 reactor using energetic electrons

    International Nuclear Information System (INIS)

    Davis, R.H.

    1984-01-01

    Two properties of energetic electrons in gas, their high specific ionization and their production of radicals and other chemically active specie, have promising applications to the cleanup of flue gas from coal combustion. The copious ionization has been used in a test particle charger to electrically charge 1 and 3 μm particles for subsequent removal by electrostatic precipitation. Particle charge greater than 5 times the theoretical ionic charging value for 1 μm particles have been observed in a bi-electrode electron beam precharger in which the beam energy is matched with the electrode spacing. In another test device, pulsed streamer coronas have been used to release and to energize electrons which promote gas phase chemical reactions and remote sulfur dioxide from humid air with high efficiency. The energized electrons produce oxidant radicals and chemically active specie which convert the SO 2 into sulfuric acid mist. While reported separately here, the two applications of energetic electrons may be amenable to combination in an integrated system for the combined treatment of flue gas

  6. Electrochemical study on the cationic promotion of the catalytic SO2 oxidation in pyrosulfate melts

    DEFF Research Database (Denmark)

    Petrushina, Irina; Bjerrum, Niels; Cappeln, Frederik Vilhelm

    1998-01-01

    The electrochemical behavior of the molten V2O5-M2S2O7 (M = K, Cs, or Na) system was studied using a gold working electrode at 440 degrees C in argon and air atmosphere. The aim of the present investigation was to find a possible correlation between the promoting effect of Cs+ and Na+ ions...... on the catalytic oxidation of SO2 in the V2O5-M2S2O7 system and the effect of these alkali cations on the electrochemical behavior of V2O5 in the alkali pyrosulfate melts It has been shown that Na+ ions had a promoting effect on the V(V) reversible arrow V(IV) electrochemical reaction. Sodium ions accelerate both...... in the catalytic SO, oxidation most likely is the oxidation of V(IV) to V(V) and the Na+ and Cs+ promoting effect is based on the acceleration of this stage. It has also been proposed that voltammetric measurements can be used for fast optimization of the composition of the vanadium catalyst (which...

  7. Rovibrational bound states of SO2 isotopologues. I: Total angular momentum J = 0-10

    Science.gov (United States)

    Kumar, Praveen; Ellis, Joseph; Poirier, Bill

    2015-04-01

    Isotopic variation of the rovibrational bound states of SO2 for the four stable sulfur isotopes 32-34,36S is investigated in comprehensive detail. In a two-part series, we compute the low-lying energy levels for all values of total angular momentum in the range J = 0-20. All rovibrational levels are computed, to an extremely high level of numerical convergence. The calculations have been carried out using the ScalIT suite of parallel codes. The present study (Paper I) examines the J = 0-10 rovibrational levels, providing unambiguous symmetry and rovibrational label assignments for each computed state. The calculated vibrational energy levels exhibit very good agreement with previously reported experimental and theoretical data. Rovibrational energy levels, calculated without any Coriolis approximations, are reported here for the first time. Among other potential ramifications, this data will facilitate understanding of the origin of mass-independent fractionation of sulfur isotopes in the Archean rock record-of great relevance for understanding the "oxygen revolution".

  8. Rovibrational bound states of SO2 isotopologues. II: Total angular momentum J = 11-20

    Science.gov (United States)

    Kumar, Praveen; Poirier, Bill

    2015-11-01

    In a two-part series, the rovibrational bound states of SO2 are investigated in comprehensive detail, for all four stable sulfur isotopes 32-34,36S. All low-lying rovibrational energy levels-both permutation-symmetry-allowed and not allowed-are computed, for all values of total angular momentum in the range J = 0-20. The calculations have carried out using the ScalIT suite of parallel codes. The present study (Paper II) examines the J = 11-20 rovibrational levels, providing symmetry and rovibrational labels for every computed state, relying on a new lambda-doublet splitting technique to make completely unambiguous assignments. Isotope shifts are analyzed, as is the validity of ;J-shifting; as a predictor of rotational fine structure. Among other ramifications, this work will facilitate understanding of mass-independent fractionation of sulfur isotopes (S-MIF) observed in the Archean rock record-particularly as this may have arisen from self shielding. S-MIF, in turn is highly relevant in the broader context of understanding the ;oxygen revolution;.

  9. The use of sulphite solutions for studying the effects of SO2 on higher plants

    International Nuclear Information System (INIS)

    Garsed, S.G.

    1981-01-01

    The effects of sulphite concentration and pH on 14 CO 2 fixation or the uptake of 35 S by needle segments of Pinus sylvestris were studied in factorial experiments. In addition, changes in the chemical composition of the sulphite solutions during the experiment were measured. Uptake of 14 CO 2 was increased and standard errors decreased by incorporating 1.0 to 10 ppm of Tween 80 into the solutions used. Inhibition of 14 CO 2 fixation by sulphite was significantly greater at low pH and high sulphite concentration, with a significant interaction. Uptake of Na 2 35 SO 3 was greater at low pH and was linear with respect to the concentration of Na 2 SO 3 carrier added between 10 -3 and 10 -4 M. In the absence of carrier, recovery of 35 S at the end of the experiment was reduced. Oxidation of the sulphite solutions was rapid at high pH and low concentration, with a significant interaction. It was also accelerated by the presence of plant material. The use of sulphite solutions to predict responses of higher plants to SO 2 is discussed. (author)

  10. Waterberg coal characteristics and SO2 minimum emissions standards in South African power plants.

    Science.gov (United States)

    Makgato, Stanford S; Chirwa, Evans M Nkhalambayausi

    2017-10-01

    Key characteristics of coal samples from the supply stock to the newly commissioned South African National Power Utility's (Eskom's) Medupi Power Station - which receives its supply coal from the Waterberg coalfield in Lephalale (Limpopo Province, South Africa) - were evaluated. Conventional coal characterisation such as proximate and ultimate analysis as well as determination of sulphur forms in coal samples were carried out following the ASTM and ISO standards. Coal was classified as medium sulphur coal when the sulphur content was detected in the range 1.15-1.49 wt.% with pyritic sulphur (≥0.51 wt.%) and organic sulphur (≥0.49 wt.%) accounted for the bulk of the total sulphur in coal. Maceral analyses of coal showed that vitrinite was the dominant maceral (up to 51.8 vol.%), whereas inertinite, liptinite, reactive semifusinite and visible minerals occurred in proportions of 22.6 vol.%, 2.9 vol.%, 5.3 vol.% and 17.5 vol.%, respectively. Theoretical calculations were developed and used to predict the resultant SO 2 emissions from the combustion of the Waterberg coal in a typical power plant. The sulphur content requirements to comply with the minimum emissions standards of 3500 mg/Nm 3 and 500 mg/Nm 3 were found to be ≤1.37 wt.% and ≤0.20 wt.%, respectively. Copyright © 2017 Elsevier Ltd. All rights reserved.

  11. Early print-tuned ERP response with minimal involvement of linguistic processing in Japanese Hiragana strings.

    Science.gov (United States)

    Okumura, Yasuko; Kasai, Tetsuko; Murohashi, Harumitsu

    2014-04-16

    The act of reading leads to the development of specific neural responses for print, the most frequently reported of which is the left occipitotemporal N170 component of event-related potentials. However, it remains unclear whether this electrophysiological response solely involves print-tuned neural activities. The present study examined an early print-tuned event-related potential response with minimal involvement of linguistic processing in a nonalphabetic language. Japanese Hiragana words, nonwords, and alphanumeric symbol strings were presented rapidly and the task was to detect the change in color of a fixation cross to restrict linguistic processing. As a result, Hiragana words and nonwords elicited a larger posterior N1 than alphanumeric symbol strings bilaterally, irrespective of intercharacter spacing. The fact that this N1 was enhanced specifically for rapidly presented Hiragana strings suggests the existence of print-tuned neural processes that are relatively independent of the influence of linguistic processing.

  12. Adsorption and oxidation of SO2 by graphene oxides: A van der Waals density functional theory study

    International Nuclear Information System (INIS)

    Zhang, Huijuan; Cen, Wanglai; Liu, Jie; Guo, Jiaxiu; Yin, Huaqiang; Ning, Ping

    2015-01-01

    Highlights: • Hydroxyl group enhances the adsorption of SO 2 on graphene oxide surface. • Hydroxyl group cuts down the barrier for the oxidation of SO 2 through H-bonding interaction. • A charge transfer channel, from surface hydroxyl group to adsorbed SO 2 molecule, and then from the adsorbed SO 2 to epoxy group, is found to underlie the promotion effects on the oxidation of SO 2 . - Abstract: Carbon materials have been used for low temperature (20–150 °C) catalytic removal of SO 2 from the coal-burned flue gases for a long time, but the mechanism at atomic level is still controversial. Density functional theory was used to investigate the adsorption and oxidation of SO 2 on elaborated graphene oxides (GOs) to discover the insights. It is found that the hydroxyl groups on GO surface possess bi-functional effects: both enhancing the adsorption of SO 2 through H-bonding interaction and reducing the reaction barrier for its oxidation to SO 3 . The promotion of oxidation is related to a pre-activation of the surface epoxy group. Based on Bader population, charge difference and electron localization function analysis, a charge transfer channel is proposed to explain the pre-activation

  13. Determination of SO2 in the atmosphere using radioactive iodine kryptonate as impregnation medium of chromatographic paper

    International Nuclear Information System (INIS)

    Pruzinec, J.

    1975-01-01

    Chromatographic paper was impregnated with radioiodine kryptonate using the macrodiffusion technique. The decrease with time of the activity of the kryptonate-impregnated paper exposed to SO 2 -contaminated air was measured. From the decrease in chromatographic paper activity, the concentration of SO 2 was determined in the range 300 to 700 ppm. (A.K.)

  14. Dry deposition of O3 and SO2 estimated from gradient measurements above a temperate mixed forest.

    Science.gov (United States)

    Wu, Zhiyong; Staebler, Ralf; Vet, Robert; Zhang, Leiming

    2016-03-01

    Vertical profiles of O3 and SO2 concentrations were monitored at the Borden Forest site in southern Ontario, Canada from May 2008 to April 2013. A modified gradient method (MGM) was applied to estimate O3 and SO2 dry deposition fluxes using concentration gradients between a level above and a level below the canopy top. The calculated five-year mean (median) dry deposition velocity (Vd) were 0.35 (0.27) and 0.59 (0.54) cm s(-1), respectively, for O3 and SO2. Vd(O3) exhibited large seasonal variations with the highest monthly mean of 0.68 cm s(-1) in August and the lowest of 0.09 cm s(-1) in February. In contrast, seasonal variations of Vd(SO2) were smaller with monthly means ranging from 0.48 (May) to 0.81 cm s(-1) (December). The different seasonal variations between O3 and SO2 were caused by the enhanced SO2 uptake by snow surfaces in winter. Diurnal variations showed a peak value of Vd in early morning in summer months for both O3 and SO2. Canopy wetness increased the non-stomatal uptake of O3 while decreasing the stomatal uptake. This also applied to SO2, but additional factors such as surface acidity also played an important role on the overall uptake. Crown Copyright © 2015. Published by Elsevier Ltd. All rights reserved.

  15. Co-adsorption of NH3 and SO2 on quartz(0 0 0 1): Formation of a stabilized complex

    NARCIS (Netherlands)

    Grecea, M.L.; Gleeson, M.A.; van Schaik, W.; Kleyn, A.W.; Bijkerk, F.

    2011-01-01

    We have investigated the co-adsorption of NH3 and SO2 on the quartz(0 0 0 1) surface by TPD and RAIRS. A surface complex is formed as a result of various relative exposures of NH3 and SO2, irrespective of dosage order. However, the relative molecular composition of the complex is dependent on the

  16. Mechanistic Aspects of the Reversible Binding of SO2 on Arylplatinum Complexes: Experimental and ab Initio Studies

    NARCIS (Netherlands)

    Koten, G. van; Albrecht, M.A.; Gossage, R.A.; Frey, H.; Ehlers, A.W.; Baerends, E.J.; Merbach, A.E.

    2001-01-01

    The detailed mechanism of the reversible binding and fast exchange of SO2 on the organoplatinum(II) complex [PtI(NCN)], 1, has been studied experimentally in solution (C2F4Br2) using low-temperature NMR spectroscopy and theoretically by ab initio calculations. Direct bonding of SO2 and formation of

  17. RETROFIT COSTS FOR SO2 AND NOX CONTROL OPTIONS AT 200 COAL-FIRED PLANTS, VOLUME I - INTRODUCTION AND METHODOLOGY

    Science.gov (United States)

    The report gives results of a study, the objective of which was to significantly improve engineering cost estimates currently being used to evaluate the economic effects of applying SO2 and NOx controls at 200 large SO2-emitting coal-fired utility plants. To accomplish the object...

  18. Volcanic SO2 fluxes derived from satellite data: a survey using OMI, GOME-2, IASI and MODIS

    Directory of Open Access Journals (Sweden)

    N. Theys

    2013-06-01

    Full Text Available Sulphur dioxide (SO2 fluxes of active degassing volcanoes are routinely measured with ground-based equipment to characterize and monitor volcanic activity. SO2 of unmonitored volcanoes or from explosive volcanic eruptions, can be measured with satellites. However, remote-sensing methods based on absorption spectroscopy generally provide integrated amounts of already dispersed plumes of SO2 and satellite derived flux estimates are rarely reported. Here we review a number of different techniques to derive volcanic SO2 fluxes using satellite measurements of plumes of SO2 and investigate the temporal evolution of the total emissions of SO2 for three very different volcanic events in 2011: Puyehue-Cordón Caulle (Chile, Nyamulagira (DR Congo and Nabro (Eritrea. High spectral resolution satellite instruments operating both in the ultraviolet-visible (OMI/Aura and GOME-2/MetOp-A and thermal infrared (IASI/MetOp-A spectral ranges, and multispectral satellite instruments operating in the thermal infrared (MODIS/Terra-Aqua are used. We show that satellite data can provide fluxes with a sampling of a day or less (few hours in the best case. Generally the flux results from the different methods are consistent, and we discuss the advantages and weaknesses of each technique. Although the primary objective of this study is the calculation of SO2 fluxes, it also enables us to assess the consistency of the SO2 products from the different sensors used.

  19. Non-isothermal effects on SO2 absorption by water droplets. I - Model development. II - Results and discussion

    Science.gov (United States)

    Reda, M.; Carmichael, G. R.

    1982-01-01

    An analytic model of SO2 absorption in a falling water droplet is developed and a simulation of SO2 washout is performed. Nonisothermic effects on drop growth, droplet physical parameters, reaction rates, and multicomponent diffusion are treated in the model. The gas-liquid interface is assumed to be at equilibrium, and interfacial resistance is negligible. Raindrops are simulated as falling from a 2 km height through an atmospheric region containing SO2. The droplets decrease in size from evaporation and cooling, and their slightly basic pH aids SO2 absorption. The simulation indicates higher SO2 absorption at higher altitudes, and desorption may occur at ground level. Isothermal effects are concluded to be significant, and quantification of effects will depend on further modelling.

  20. Improvement of wine aromatic quality using mixtures of lysozyme and dimethyl dicarbonate, with low SO2 concentration.

    Science.gov (United States)

    Nieto-Rojo, Rodrigo; Luquin, Asuncion; Ancín-Azpilicueta, Carmen

    2015-01-01

    The use of sulphur dioxide (SO2) in the treatment of foodstuffs presents some problems as it could lead to pseudo-allergies in some people. The aim of this research work was to study the addition of different preservative mixtures and their influence on the concentration of volatile compounds and sensorial quality in wine. To do so, vinifications were carried out using Garnacha must to which lysozyme, dimethyl dicarbonate (DMDC) and mixtures of these with SO2 were added at different doses (25 and 50 mg l(-1)). The results were compared with a control sample to which only SO2 had been added (50 mg l(-1)). In general, mixtures of SO2 with lysozyme and DMDC favoured the formation of volatile compounds in the wines. Wines obtained from the mixtures of lysozyme and DMDC with 25 mg l(-1) of SO2 had better sensorial quality than the wines obtained with 50 mg l(-1) as the only preservative used.

  1. TRAINING DURING ISO 9001 IMPLEMENTATION AND WORKERS INVOLVEMENT INTO THE QUALITY MANAGEMENT PROCESS IN MONTENEGRO

    Directory of Open Access Journals (Sweden)

    Marc-Arthur Diaye

    2009-03-01

    Full Text Available According to several researchers, workers involvement into the implementation of a quality system in a firm is a key of its success. Since training can improve workers involvement during the implementation of a quality system in a firm, we try in this paper to evaluate quantitatively in the case of Montenegro, the impact of training of workers' involvement. Using an original data set about two leading firms from Montenegro, we show that the coefficient associated with the training variable is on average about -1.44 and is significant at a level of 1%. That is workers who are not trained during the ISO 9001 implementation are strongly less involved into the quality management process of their firms.

  2. Tightening the Purchasing Process: Superintendents Get More Involved in Buying Policies

    Science.gov (United States)

    Rivero, Victor

    2009-01-01

    Over the last 18 months, school district purchasing offices across the country have been tightening the reins like never before while more top-level administrators get involved in the budget process. "When the economy really hit the skids, states got hit hard, so a lot of school districts were forced to make severe budget cuts," says John Musso,…

  3. Links between social information processing in middle childhood and involvement in bullying. [IF 0.95

    NARCIS (Netherlands)

    Camodeca, M.; Goossens, F.A.; Schuengel, C.; Meerum Terwogt, M.

    2003-01-01

    The aim of this study was to investigate the way in which bullies, victims, bully/victims, and those not involved process social information. A peer nomination measure of bullying and victimization was administered twice over an interval of one year. The sample consisted of 236 (126 girls and 110

  4. Reflections on Practical Approaches to Involving Children and Young People in the Data Analysis Process

    Science.gov (United States)

    Coad, Jane; Evans, Ruth

    2008-01-01

    This article reflects on key methodological issues emerging from children and young people's involvement in data analysis processes. We outline a pragmatic framework illustrating different approaches to engaging children, using two case studies of children's experiences of participating in data analysis. The article highlights methods of…

  5. Perceptions of legally mandated public involvement processes in the U.S. Forest Service

    Science.gov (United States)

    S. Andrew Predmore; Marc J. Stern; Michael J. Mortimer; David N. Seesholtz

    2011-01-01

    Results from an agency-wide survey of U.S. Forest Service personnel indicate that respondents in our sample engage in National Environmental Policy Act (NEPA) public involvement processes primarily to accomplish two goals. The most commonly supported goal was to inform and disclose as mandated by the act. The other goal reflected interests in managing agency...

  6. ADHD Coaching with College Students: Exploring the Processes Involved in Motivation and Goal Completion

    Science.gov (United States)

    Prevatt, Frances; Smith, Shannon M.; Diers, Sarah; Marshall, Diana; Coleman, Jennifer; Valler, Emilee; Miller, Nathan

    2017-01-01

    College students with attention-deficit/hyperactivity disorder (ADHD) often experience increased academic difficulties, which can negatively impact graduation rates, employment, self-esteem, and mental health. ADHD coaching assists students with ADHD to reduce such difficulties. The present study evaluated the processes involved in ADHD coaching…

  7. Noble metal (Pt or Au)-doped monolayer MoS2 as a promising adsorbent and gas-sensing material to SO2, SOF2 and SO2F2: a DFT study

    Science.gov (United States)

    Chen, Dachang; Zhang, Xiaoxing; Tang, Ju; Cui, Hao; Li, Yi

    2018-02-01

    We explored the adsorption of SO2, SOF2, and SO2F2 on Pt- or Au-doped MoS2 monolayer based on density functional theory. The adsorption energy, adsorption distance, charge transfer as well as density of states were discussed. SO2 and SOF2 exhibit strong chemical interactions with Pt-doped MoS2 based on large adsorption energy, charge transfer, and changes of electron orbitals in gas molecule. SO2 also shows obvious chemisorption on Au-doped MoS2 with apparent magnetism transfer from Au to gas molecules. The adsorption of SO2F2 on Pt-MoS2 and SOF2 on Au-MoS2 exhibits weaker chemical interactions and SO2F2 losses electrons when adsorbed on Pt-MoS2 which is different from other gas adsorption. The adsorption of SO2F2 on Au-MoS2 represents no obvious chemical interaction but physisorption. The gas-sensing properties are also evaluated based on DFT results. This work could provide prospects and application value for typical noble metal-doped MoS2 as gas-sensing materials.

  8. The primary volcanic aerosol emission from Mt Etna: Size-resolved particles with SO2 and role in plume reactive halogen chemistry

    Science.gov (United States)

    Roberts, T. J.; Vignelles, D.; Liuzzo, M.; Giudice, G.; Aiuppa, A.; Coltelli, M.; Salerno, G.; Chartier, M.; Couté, B.; Berthet, G.; Lurton, T.; Dulac, F.; Renard, J.-B.

    2018-02-01

    Volcanoes are an important source of aerosols to the troposphere. Within minutes after emission, volcanic plume aerosol catalyses conversion of co-emitted HBr, HCl into highly reactive halogens (e.g. BrO, OClO) through chemical cycles that cause substantial ozone depletion in the dispersing downwind plume. This study quantifies the sub-to-supramicron primary volcanic aerosol emission (0.2-5 μm diameter) and its role in this process. An in-situ ground-based study at Mt Etna (Italy) during passive degassing co-deployed an optical particle counter and Multi-Gas SO2 sensors at high time resolution (0.1 Hz) enabling to characterise the aerosol number, size-distribution and emission flux. A tri-modal volcanic aerosol size distribution was found, to which lognormal distributions are fitted. Total particle volume correlates to SO2 (as a plume tracer). The measured particle volume:SO2 ratio equates to a sulfate:SO2 ratio of 1-2% at the observed meteorological conditions (40% Relative Humidity). A particle mass flux of 0.7 kg s-1 is calculated for the measured Mt Etna SO2 flux of 1950 tonnes/day. A numerical plume atmospheric chemistry model is used to simulate the role of the hygroscopic primary aerosol surface area and its humidity dependence on volcanic plume BrO and OClO chemistry. As well as predicting volcanic BrO formation and O3 depletion, the model achieves OClO/SO2 in broad quantitative agreement with recently reported Mt Etna observations, with a predicted maximum a few minutes downwind. In addition to humidity - that enhances aerosols surface area for halogen cycling - background ozone is predicted to be an important control on OClO/SO2. Dependence of BrO/SO2 on ambient humidity is rather low near-to-source but increases further downwind. The model plume chemistry also exhibits strong across-plume spatial variations between plume edge and centre.

  9. Concurrent removal of elemental mercury and SO2 from flue gas using a thiol-impregnated CaCO3-based adsorbent: a full factorial design study.

    Science.gov (United States)

    Balasundaram, Karthik; Sharma, Mukesh

    2018-03-22

    Mercury (Hg) emitted from coal-based thermal power plants (CTPPs) can accumulate and bio-magnify in the food chain, thereby posing a risk to humans and wildlife. The central idea of this study was to develop an adsorbent which can concurrently remove elemental mercury (Hg 0 ) and SO 2 emitted from coal-based thermal power plants (CTPPs) in a single unit operation. Specifically, a composite adsorbent of CaCO 3 impregnated with 2-mercaptobenimidazole (2-MBI) (referred to as modified calcium carbonate (MCC)) was developed. While 2-MBI having sulfur functional group could selectively adsorb Hg 0 , CaCO 3 could remove SO 2 . Performance of the adsorbent was evaluated in terms of (i) removal (%) of Hg 0 and SO 2 , (ii) adsorption mechanism, (iii) adsorption kinetics, and (iv) leaching potential of mercury from spent adsorbent. The adsorption studies were performed using a 2 2 full factorial design of experiments with 15 ppbV of Hg 0 and 600 ppmV of SO 2 . Two factors, (i) reaction temperature (80 and 120 °C; temperature range in flue gas) and (ii) mass of 2-MBI (10 and 15 wt%), were investigated for the removal of Hg 0 and SO 2 (as %). The maximum Hg 0 and SO 2 removal was 86 and 93%, respectively. The results of XPS characterization showed that chemisorption is the predominant mechanism of Hg 0 and SO 2 adsorption on MCC. The Hg 0 adsorption on MCC followed Elovich kinetic model which is also indicative of chemisorption on heterogeneous surface. The toxicity characteristic leaching procedure (TCLP) and synthetic precipitation leaching procedure (SPLP) leached mercury from the spent adsorbent were within the acceptable levels defined in these tests. The engineering significance of this study is that the 2-MBI-modified CaCO 3 -based adsorbent has potential for concurrent removal of Hg 0 and SO 2 in a single unit operation. With only minor process modifications, the newly developed adsorbent can replace CaCO 3 in the flue-gas desulfurization (FGD) system.

  10. Mobility of persons who are blind: How the attentional processes and working memory are involved?

    OpenAIRE

    PIGEON, Caroline; MARIN-LAMELLET, Claude

    2015-01-01

    Although navigation without vision seems to strongly mobilize the attentional processes and the working memory, few studies seem to be conducted about the link between these processes and the mobility of people who are blind. The main aim of this PhD work is to consider the attentional and working memory capacities of people who are blind and investigate the attentional processes involved during the navigation activity. In the first part of this PhD work, blind participants (early and late) p...

  11. Cochlear Implant: the complexity involved in the decision making process by the family

    Directory of Open Access Journals (Sweden)

    Sheila de Souza Vieira

    2014-06-01

    Full Text Available OBJECTIVE: to understand the meanings the family attributes to the phases of the decision-making process on a cochlear implant for their child.METHOD: qualitative research, using Symbolic Interactionism and Grounded Theory as the theoretical and methodological frameworks, respectively. Data collection instrument: semistructured interview. Nine families participated in the study (32 participants.RESULTS: knowledge deficit, difficulties to contextualize benefits and risks and fear are some factors that make this process difficult. Experiences deriving from interactions with health professionals, other cochlear implant users and their relatives strengthen decision making in favor of the implant.CONCLUSION: deciding on whether or not to have the implant involves a complex process, in which the family needs to weigh gains and losses, experience feelings of accountability and guilt, besides overcoming the risk aversion. Hence, this demands cautious preparation and knowledge from the professionals involved in this intervention.

  12. Cochlear Implant: the complexity involved in the decision making process by the family.

    Science.gov (United States)

    Vieira, Sheila de Souza; Bevilacqua, Maria Cecília; Ferreira, Noeli Marchioro Liston Andrade; Dupas, Giselle

    2014-01-01

    to understand the meanings the family attributes to the phases of the decision-making process on a cochlear implant for their child. qualitative research, using Symbolic Interactionism and Grounded Theory as the theoretical and methodological frameworks, respectively. Data collection instrument: semistructured interview. Nine families participated in the study (32 participants). knowledge deficit, difficulties to contextualize benefits and risks and fear are some factors that make this process difficult. Experiences deriving from interactions with health professionals, other cochlear implant users and their relatives strengthen decision making in favor of the implant. deciding on whether or not to have the implant involves a complex process, in which the family needs to weigh gains and losses, experience feelings of accountability and guilt, besides overcoming the risk aversion. Hence, this demands cautious preparation and knowledge from the professionals involved in this intervention.

  13. Cochlear Implant: the complexity involved in the decision making process by the family1

    Science.gov (United States)

    Vieira, Sheila de Souza; Bevilacqua, Maria Cecília; Ferreira, Noeli Marchioro Liston Andrade; Dupas, Giselle

    2014-01-01

    Objective to understand the meanings the family attributes to the phases of the decision-making process on a cochlear implant for their child. Method qualitative research, using Symbolic Interactionism and Grounded Theory as the theoretical and methodological frameworks, respectively. Data collection instrument: semistructured interview. Nine families participated in the study (32 participants). Results knowledge deficit, difficulties to contextualize benefits and risks and fear are some factors that make this process difficult. Experiences deriving from interactions with health professionals, other cochlear implant users and their relatives strengthen decision making in favor of the implant. Conclusion deciding on whether or not to have the implant involves a complex process, in which the family needs to weigh gains and losses, experience feelings of accountability and guilt, besides overcoming the risk aversion. Hence, this demands cautious preparation and knowledge from the professionals involved in this intervention. PMID:25029052

  14. Final report on the public involvement process phase 1, Monitored Retrievable Storage Facility Feasibility Study

    International Nuclear Information System (INIS)

    Moore, L.; Shanteau, C.

    1992-12-01

    This report summarizes the pubic involvement component of Phase 1 of the Monitored Retrievable Storage Facility (NM) Feasibility Study in San Juan County, Utah. Part of this summary includes background information on the federal effort to locate a voluntary site for temporary storage of nuclear waste, how San Juan County came to be involved, and a profile of the county. The heart of the report, however, summarizes the activities within the public involvement process, and the issues raised in those various forums. The authors have made every effort to reflect accurately and thoroughly all the concerns and suggestions expressed to us during the five month process. We hope that this report itself is a successful model of partnership with the citizens of the county -- the same kind of partnership the county is seeking to develop with its constituents. Finally, this report offers some suggestions to both county officials and residents alike. These suggestions concern how decision-making about the county's future can be done by a partnership of informed citizens and listening decision-makers. In the Appendix are materials relating to the public involvement process in San Juan County

  15. Final report on the public involvement process phase 1, Monitored Retrievable Storage Facility Feasibility Study

    Energy Technology Data Exchange (ETDEWEB)

    Moore, L.; Shanteau, C.

    1992-12-01

    This report summarizes the pubic involvement component of Phase 1 of the Monitored Retrievable Storage Facility (NM) Feasibility Study in San Juan County, Utah. Part of this summary includes background information on the federal effort to locate a voluntary site for temporary storage of nuclear waste, how San Juan County came to be involved, and a profile of the county. The heart of the report, however, summarizes the activities within the public involvement process, and the issues raised in those various forums. The authors have made every effort to reflect accurately and thoroughly all the concerns and suggestions expressed to us during the five month process. We hope that this report itself is a successful model of partnership with the citizens of the county -- the same kind of partnership the county is seeking to develop with its constituents. Finally, this report offers some suggestions to both county officials and residents alike. These suggestions concern how decision-making about the county's future can be done by a partnership of informed citizens and listening decision-makers. In the Appendix are materials relating to the public involvement process in San Juan County.

  16. Final report on the public involvement process phase 1, Monitored Retrievable Storage Facility Feasibility Study

    Energy Technology Data Exchange (ETDEWEB)

    Moore, L.; Shanteau, C.

    1992-12-01

    This report summarizes the pubic involvement component of Phase 1 of the Monitored Retrievable Storage Facility (NM) Feasibility Study in San Juan County, Utah. Part of this summary includes background information on the federal effort to locate a voluntary site for temporary storage of nuclear waste, how San Juan County came to be involved, and a profile of the county. The heart of the report, however, summarizes the activities within the public involvement process, and the issues raised in those various forums. The authors have made every effort to reflect accurately and thoroughly all the concerns and suggestions expressed to us during the five month process. We hope that this report itself is a successful model of partnership with the citizens of the county -- the same kind of partnership the county is seeking to develop with its constituents. Finally, this report offers some suggestions to both county officials and residents alike. These suggestions concern how decision-making about the county`s future can be done by a partnership of informed citizens and listening decision-makers. In the Appendix are materials relating to the public involvement process in San Juan County.

  17. Formation of secondary aerosols from the ozonolysis of styrene: Effect of SO2 and H2O

    Science.gov (United States)

    Díaz-de-Mera, Yolanda; Aranda, Alfonso; Martínez, Ernesto; Rodríguez, Ana Angustias; Rodríguez, Diana; Rodríguez, Ana

    2017-12-01

    In this work we report the study of the ozonolysis of styrene and the reaction conditions leading to the formation of secondary aerosols. The reactions have been carried out in a Teflon chamber filled with synthetic air mixtures at atmospheric pressure and room temperature. We have found that the ozonolysis of styrene in the presence of low concentrations of SO2 readily produces new particles under concentrations of reactants lower than those required in experiments in the absence of SO2. Thus, nucleation events occur at concentrations around (5.6 ± 1.7) × 108molecule cm-3 (errors are 2σ±20%) and SO2 is consumed during the experiments. The reaction of the Criegee intermediates with SO2 to produce SO3 and then H2SO4 may explain (together with OH reactions' contribution) the high capacity of styrene to produce particulate matter in polluted atmospheres. The formation of secondary aerosols in the smog chamber is inhibited under high H2O concentrations. So, the potential formation of secondary aerosols under atmospheric conditions depends on the concentration of SO2 and relative humidity, with a water to SO2 rate constants ratio kH2O/kSO2 = (2.8 ± 0.7) × 10-5 (errors are 2σ±20%).

  18. Simultaneous absorption of SO2 and NO from flue gas with KMnO4/NaOH solutions

    International Nuclear Information System (INIS)

    Chu, H.; Chien, T.W.; Li, S.Y.

    2001-01-01

    The wet scrubbing combined SO x /NO x removal system is an advanced air pollution control device. This study attempts to understand the absorption kinetics in the system. The absorption of diluted SO 2 and simultaneous absorption of diluted SO 2 and NO, as occurs in flue gases, in a stirred tank reactor with KMnO 4 /NaOH solutions were carried out at 50C. The liquid-side and gas-side mass transfer coefficients of the system were determined. The results indicate that the absorption of SO 2 is close to completely gas-film controlled where the NaOH concentration is greater than 0.1 M or the KMnO 4 concentration is greater than 0.05 M. The increasing gas flow rate has a positive effect on the absorption rate of SO 2 . The existence of O 2 has no significant effect on the absorption rate of SO 2 . Adding SO 2 would decrease the absorption rate of NO; however, the addition of NO has no effect on the absorption rate of SO 2

  19. Infrared Spectra of Novel NgBeSO2 Complexes (Ng = Ne, Ar, Kr, Xe) in Low Temperature Matrixes.

    Science.gov (United States)

    Yu, Wenjie; Liu, Xing; Xu, Bing; Xing, Xiaopeng; Wang, Xuefeng

    2016-11-03

    The novel noble-gas complexes NgBeSO 2 (Ng = Ne, Ar, Kr, Xe) have been prepared in the laser-evaporated beryllium atom reactions with SO 2 in low-temperature matrixes. Doped with heavier noble gas, the guest (Ar, Kr, Xe) atom can substitute neon to form more stable complex. Infrared spectroscopy and theoretical calculations are used to confirm the band assignment. The dissociation energies are calculated at 0.9, 4.0, 4.7, and 6.0 kcal/mol for NeBeSO 2 , ArBeSO 2 , KrBeSO 2 , and XeBeSO 2 , respectively, at the CCSD(T) level. Quantum chemical calculations demonstrate that the Ng-Be bonds in NgBeSO 2 could be formed by the combination of electron-donation and ion-induced dipole interactions. The Wiberg bond index (WBI) values of Ng-Be bonds and LOL (localized orbital locator) profile indicate that the Ng-Be bond exhibits a gradual increase in covalent character along Ne to Xe.

  20. Photoacoustic-based sO2 estimation through excised bovine prostate tissue with interstitial light delivery.

    Science.gov (United States)

    Mitcham, Trevor; Taghavi, Houra; Long, James; Wood, Cayla; Fuentes, David; Stefan, Wolfgang; Ward, John; Bouchard, Richard

    2017-09-01

    Photoacoustic (PA) imaging is capable of probing blood oxygen saturation (sO 2 ), which has been shown to correlate with tissue hypoxia, a promising cancer biomarker. However, wavelength-dependent local fluence changes can compromise sO 2 estimation accuracy in tissue. This work investigates using PA imaging with interstitial irradiation and local fluence correction to assess precision and accuracy of sO 2 estimation of blood samples through ex vivo bovine prostate tissue ranging from 14% to 100% sO 2 . Study results for bovine blood samples at distances up to 20 mm from the irradiation source show that local fluence correction improved average sO 2 estimation error from 16.8% to 3.2% and maintained an average precision of 2.3% when compared to matched CO-oximeter sO 2 measurements. This work demonstrates the potential for future clinical translation of using fluence-corrected and interstitially driven PA imaging to accurately and precisely assess sO 2 at depth in tissue with high resolution.

  1. Rates of volcanic CO2 degassing from airborne determinations of SO2 Emission rates and plume CO2SO2: test study at Pu′u ′O′o Cone, Kilauea Volcano, Hawaii

    Science.gov (United States)

    Gerlach, Terrence M.; McGee, Kenneth A.; Sutton, A. Jefferson; Elias, Tamar

    1998-01-01

    We present an airborne method that eliminates or minimizes several disadvantages of the customary plume cross-section sampling method for determining volcanic CO2 emission rates. A LI-COR CO2analyzer system (LICOR), a Fourier transform infrared spectrometer system (FTIR), and a correlation spectrometer (COSPEC) were used to constrain the plume CO2/SO2 and the SO2 emission rate. The method yielded a CO2 emission rate of 300 td−1 (metric tons per day) for Pu′u ′O′o cone, Kilauea volcano, on 19 September 1995. The CO2/SO2 of 0.20 determined from airborne LICOR and FTIR plume measurements agreed with the CO2/SO2 of 204 ground-based samples collected from vents over a 14-year period since the Pu′u ′O′o eruption began in January 1983.

  2. Validating the accuracy of SO2 gas retrievals in the thermal infrared (8-14 μm)

    Science.gov (United States)

    Gabrieli, Andrea; Porter, John N.; Wright, Robert; Lucey, Paul G.

    2017-11-01

    Quantifying sulfur dioxide (SO2) in volcanic plumes is important for eruption predictions and public health. Ground-based remote sensing of spectral radiance of plumes contains information on the path-concentration of SO2. However, reliable inversion algorithms are needed to convert plume spectral radiance measurements into SO2 path-concentrations. Various techniques have been used for this purpose. Recent approaches have employed thermal infrared (TIR) imaging between 8 μm and 14 μm to provide two-dimensional mapping of plume SO2 path-concentration, using what might be described as "dual-view" techniques. In this case, the radiance (or its surrogate brightness temperature) is computed for portions of the image that correspond to the plume and compared with spectral radiance obtained for adjacent regions of the image that do not (i.e., "clear sky"). In this way, the contribution that the plume makes to the measured radiance can be isolated from the background atmospheric contribution, this residual signal being converted to an estimate of gas path-concentration via radiative transfer modeling. These dual-view approaches suffer from several issues, mainly the assumption of clear sky background conditions. At this time, the various inversion algorithms remain poorly validated. This paper makes two contributions. Firstly, it validates the aforementioned dual-view approaches, using hyperspectral TIR imaging data. Secondly, it introduces a new method to derive SO2 path-concentrations, which allows for single point SO2 path-concentration retrievals, suitable for hyperspectral imaging with clear or cloudy background conditions. The SO2 amenable lookup table algorithm (SO2-ALTA) uses the MODTRAN5 radiative transfer model to compute radiance for a variety (millions) of plume and atmospheric conditions. Rather than searching this lookup table to find the best fit for each measured spectrum, the lookup table was used to train a partial least square regression (PLSR) model

  3. Fireside Corrosion Behaviors of Super304H and HR3C in Coal Ash/Gas Environment with Different SO2 Contents at 650 °C

    Science.gov (United States)

    Lu, Jintao; Yang, Zhen; Li, Yan; Huang, Jinyang; Zhou, Yongli; Zhao, Xinbao; Yuan, Yong

    2018-05-01

    The corrosion behaviors of Super304H and HR3C used for USC boiler applications were investigated in simulated coal ash/gas environments with 0.1 and 1.5% of SO2 at 650 °C for 500 h. The results indicated that the increase in SO2 accelerated the corrosion rate and the spalling tendency of the corrosion layer in both tested alloys. Fe2O3, Cr2O3 and FeCr2O4 main peaks were revealed by XRD on Super304H, but on HR3C only the Cr2O3 peak showed a high intensity. The SO2 content did not affect the corrosion product composition of any of the alloys, but accelerated the inner sulfidation and the spallation on Super304H. No obvious internal sulfidation was observed on HR3C in either SO2 content. Based on the experimental results, the alloy corrosion mechanism and the influence of sulfur content on the corrosion process were discussed.

  4. Spatial and temporal evaluation of long term trend (2005-2014) of OMI retrieved NO2 and SO2 concentrations in Henan Province, China

    Science.gov (United States)

    Zhang, Leishi; Lee, Chih Sheng; Zhang, Ruiqin; Chen, Liangfu

    2017-04-01

    Tropospheric NO2 and SO2 concentrations are of great importance with regard to air quality, atmospheric chemistry, and climate change. Due to lack of surface monitoring stations, this study analyzes long term trend of NO2 and SO2 levels (2005-2014), retrieved from Ozone Monitoring Instrument (OMI) board on the NASA's Aura satellite, in an important region of China - Henan Province. Henan Province, located in North China Plain, has encountered serious air pollution problems including extremely high PM2.5 concentrations and as one of the most polluted region in China. The satellite spatial images clearly show that high levels of both NO2 and SO2 are concentrated in north and northeastern regions with much lower levels observed in other parts of Henan. Both pollutants exhibit the highest levels in winter with the least in summer/spring. The temporal trend analysis based on moving average of deseasonalized and decyclic data indicates that for NO2, there is a continuous increasing pattern from 2005 to 2011 at 6.4% per year, thereafter, it shows a decreasing trend (10.6% per year). As for SO2, the increasing trend is about 16% per year from 2005 to 2007 with decreasing rate 7% per year from 2007 to 2014. The economic development with incredible annual 11% GDP growth in Henan is responsible for increasing levels of NO2 and SO2. The observed decreasing SO2 level starting in 2007 is due to reduced SO2 emission, utilization of flue gas desulfurization (FGD) devices and to some extent, in preparation of Beijing 2008 Olympic Games. On the other hand, increasing vehicle numbers (155% from 2006 to 2012) and coal consumption (37% during the same span), along with the lack of denitration process for removing flue/exhaust gas NOx are responsible for increasing NO2 trend until 2011. The ratio of SO2/NO2 started decreasing in 2007 and dropped significantly from 2011 to 2013 indicating good performance of FGD and ever increasing NOx contribution from mobile sources. Unlike those

  5. Functional brain imaging study on brain processes involved in visual awareness

    International Nuclear Information System (INIS)

    Kobayashi, Tetsuo; Futakawa, Hiroyuki; Tokita, Shohko; Jung, Jiuk

    2003-01-01

    Recently, there has been great interest in visual awareness because it is thought that it may provide valuable information in understanding aspects of consciousness. An important but still controversial issue is what region in the brain is involved in visual awareness. When viewing ambiguous figures, observers can be aware of only one of multiple competing percepts at any given moment, but experience spontaneous alternations among the percepts over time. This phenomenon is known as multistable perceptions and thought to be essential in understanding the brain processes involved in visual awareness. We used functional magnetic resonance imaging to investigate the brain activities associated with multistable perceptions. Two separate experiments were performed based on two different multistable phenomena known as binocular rivalry and perceptions of ambiguous figures. Significant differential activations in the parietal and prefrontal areas were commonly observed under multistable conditions compared to monostable control conditions in the two separate experiments. These findings suggest that neural processes in the parietal and prefrontal areas may be involved in perceptual alternations in situations involving multistable phenomena. (author)

  6. Diversity for design: A framework for involving neurodiverse children in the technology design process

    OpenAIRE

    Benton, L.; Vasalou, A.; Khaled, R.; Johnson, H.; Gooch, D.

    2014-01-01

    The neurodiversity movement seeks to positively reframe certain neurological conditions, such as autism spectrum disorders (ASD) and dyslexia, by concentrating on their strengths. In recent years, neurodiverse children have increasingly been involved in the technology design process, but the design approaches adopted have focused mostly on overcoming difficulties of working with these children, leaving their strengths untapped. We present a new participatory design (PD) framework, Diversity f...

  7. Diversity for design : a framework for involving neurodiverse children in the technology design process

    OpenAIRE

    Benton, Laura; Vasalou, Asimina; Khaled, Rilla; Johnson, Hilary; Gooch, Daniel

    2014-01-01

    The neurodiversity movement seeks to positively reframe certain neurological conditions, such as autism spectrum disorders (ASD) and dyslexia, by concentrating on their strengths. In recent years, neurodiverse children have increasingly been involved in the technology design process, but the design approaches adopted have focused mostly on overcoming difficulties of working with these children, leaving their strengths untapped. We present a new participatory design (PD) framework, Diversity f...

  8. Reactions of SO 2 on hydrated cement particle system for atmospheric pollution reduction: A DRIFTS and XANES study

    Energy Technology Data Exchange (ETDEWEB)

    Ramakrishnan, Girish; Wu, Qiyuan; Moon, Juhyuk; Orlov, Alexander

    2017-07-01

    An investigation of the adsorptive property of hydrated cement particle system for sulfur dioxide (SO2) removal was conducted. In situ and ex situ experiments using Diffuse Reflectance Infrared Fourier Transform Spectroscopy (DRIFTS) and X-ray Absorption Near Edge Spectroscopy (XANES) characterization techniques were employed to identify surface species formed during the exposure to SO2. Oxidation of SO2 to sulfate and sulfite species observed during these experiments indicated dominant reaction pathways for SO2 reaction with concrete constituents, such as calcium hydroxide, which were also moderated by adsorption on porous surfaces of crushed aggregates. The impact of variable composition of concrete on its adsorption capacity and reaction mechanisms was also proposed in this work.

  9. Domain general sequence operations contribute to pre-SMA involvement in visuo-spatial processing

    Directory of Open Access Journals (Sweden)

    E. Charles eLeek

    2016-01-01

    Full Text Available This study used 3T MRI to elucidate the functional role of supplementary motor area (SMA in relation to visuo-spatial processing. A localizer task contrasting sequential number subtraction and repetitive button pressing was used to functionally delineate non-motor sequence processing in pre-SMA, and activity in SMA-proper associated with motor sequencing. Patterns of BOLD responses in these regions were then contrasted to those from two tasks of visuo-spatial processing. In one task participants performed mental rotation in which recognition memory judgments were made to previously memorized 2D novel patterns across image-plane rotations. The other task involved abstract grid navigation in which observers computed a series of imagined location shifts in response to directional (arrow cues around a mental grid. The results showed overlapping activation in pre-SMA for sequential subtraction and both visuo-spatial tasks. These results suggest that visuo-spatial processing is supported by non-motor sequence operations that involve pre-SMA. More broadly, these data further highlight the functional heterogeneity of pre-SMA, and show that its role extends to processes beyond the planning and online control of movement.

  10. Dry deposition of O_3 and SO_2 estimated from gradient measurements above a temperate mixed forest

    International Nuclear Information System (INIS)

    Wu, Zhiyong; Staebler, Ralf; Vet, Robert; Zhang, Leiming

    2016-01-01

    Vertical profiles of O_3 and SO_2 concentrations were monitored at the Borden Forest site in southern Ontario, Canada from May 2008 to April 2013. A modified gradient method (MGM) was applied to estimate O_3 and SO_2 dry deposition fluxes using concentration gradients between a level above and a level below the canopy top. The calculated five-year mean (median) dry deposition velocity (V_d) were 0.35 (0.27) and 0.59 (0.54) cm s"−"1, respectively, for O_3 and SO_2. V_d(O_3) exhibited large seasonal variations with the highest monthly mean of 0.68 cm s"−"1 in August and the lowest of 0.09 cm s"−"1 in February. In contrast, seasonal variations of V_d(SO_2) were smaller with monthly means ranging from 0.48 (May) to 0.81 cm s"−"1 (December). The different seasonal variations between O_3 and SO_2 were caused by the enhanced SO_2 uptake by snow surfaces in winter. Diurnal variations showed a peak value of V_d in early morning in summer months for both O_3 and SO_2. Canopy wetness increased the non-stomatal uptake of O_3 while decreasing the stomatal uptake. This also applied to SO_2, but additional factors such as surface acidity also played an important role on the overall uptake. - Highlights: • Application of a modified gradient-method for quantifying dry deposition is demonstrated. • A five-year dry deposition database is developed for O_3 and SO_2 over a mixed forest. • Canopy wetness enhances non-stomatal O_3 uptake while inhibits stomatal uptake. • High surface acidity reduces SO_2 dry deposition. - Capsule: A five-year dataset of O_3 and SO_2 dry deposition velocities was generated from concentration gradient measurement data using a modified gradient method.

  11. The difficulties experienced by nurses and healthcare staff involved in the process of breaking bad news.

    Science.gov (United States)

    Warnock, Clare; Buchanan, Jean; Tod, Angela Mary

    2017-07-01

    The aim of this study was to explore the difficulties experienced by nurses and healthcare professionals when engaging in the process of breaking bad news. The challenges faced by staff when breaking bad news have previously been researched in relation to particular settings or participants. This study involved staff from diverse settings and roles to develop broader insights into the range of difficulties experienced in clinical practice. The study used a descriptive survey design involving self-reported written accounts and framework analysis. Data were collected using a structured questionnaire containing a free text section that asked participants to describe a difficult experience they had encountered when involved in the process of breaking bad news. Data were collected from healthcare staff from hospital, community, hospice and care home settings attending training days on breaking bad news between April 2011 and April 2014. Multiple inter-related factors presented challenges to staff engaging in activities associated with breaking bad news. Traditional subjects such as diagnostic and treatment information were described but additional topics were identified such as the impact of illness and care at the end of life. A descriptive framework was developed that summarizes the factors that contribute to creating difficult experiences for staff when breaking bad news. The framework provides insights into the scope of the challenges faced by staff when they engage in the process of breaking bad news. This provides the foundation for developing interventions to support staff that more closely matches their experiences in clinical practice. © 2017 John Wiley & Sons Ltd.

  12. Effects of SO2 emission regulations and fuel prices on levellized energy costs for industrial steam generation options

    International Nuclear Information System (INIS)

    Ozdogan, Sibel; Arikol, Mahir

    1992-01-01

    We discuss the impacts of SO 2 emission regulations and fuel prices on levellized energy costs of industrial steam generation options. A computer model called INDUSTEAM has been utilized. The steam-supply options comprise conventional grate-firing, bubbling and circulating fluidized beds, fuel-oil, and natural-gas-fired systems. Fuels of different SO 2 pollution potential have been evaluated assuming six environmental scenarios and varying fuel prices. A capacity range of 10-90 MW th is covered. (author)

  13. Structural Characterization of 1,1,3,3-Tetramethylguanidinium Chloride Ionic Liquid by Reversible SO2 Gas Absorption

    DEFF Research Database (Denmark)

    Berg, Rolf W.; Harris, Pernille; Riisager, Anders

    2013-01-01

    A unique new ionic liquid−gas adduct solid state compound formed between 1,1,3,3-tetramethylguanidinium chloride ([tmgH]Cl) and sulfur dioxide has been characterized by X-ray diffraction and Raman spectroscopy. The structure contains SO2 molecules of near normal structure kept at their positions ...... with bromide and iodide are discussed. Some of these salts may prove useful as reversible absorbents of SO2 in industrial flue gases....

  14. SO3 formation from the X-ray photolysis of SO2 astrophysical ice analogues: FTIR spectroscopy and thermodynamic investigations.

    Science.gov (United States)

    de Souza Bonfim, Víctor; Barbosa de Castilho, Roberto; Baptista, Leonardo; Pilling, Sergio

    2017-10-11

    In this combined experimental-theoretical work we focus on the physical and chemical changes induced by soft X-rays on sulfur dioxide (SO 2 ) ice at a very low temperature, in an attempt to clarify and quantify its survival and chemical changes in some astrophysical environments. SO 2 is an important constituent of some Jupiter moons and has also been observed in ices around protostars. The measurements were performed at the Brazilian Synchrotron Light Source (LNLS/CNPEM), in Campinas, Brazil. The SO 2 ice sample (12 K) was exposed to a broadband beam of mainly soft X-rays (6-2000 eV) and in situ analyses were performed by IR spectroscopy. The X-ray photodesorption yield (upper limit) was around 0.25 molecules per photon. The values determined for the effective destruction (SO 2 ) and formation (SO 3 ) cross sections were 2.5 × 10 -18 cm 2 and 2.1 × 10 -18 cm 2 , respectively. The chemical equilibrium (88% of SO 2 and 12% of SO 3 ) was reached after the fluence of 1.6 × 10 18 photons cm -2 . The SO 3 formation channels were studied at the second-order Møller-Plesset perturbation theory (MP2) level, which showed the three most favorable reaction routes (ΔH < -79 kcal mol -1 ) in simulated SO 2 ice: (i) SO + O 2 → SO 3 , (ii) SO 2 + O → SO 3 , and (iii) SO 2 + O + → SO 3 + + e - → SO 3 . The amorphous solid environment effect decreases the reactivity of intermediate species towards SO 3 formation, and ionic species are even more affected. The experimentally determined effective cross sections and theoretical reaction channels identified in this work allow us to better understand the chemical evolution of certain sulfur-rich astrophysical environments.

  15. SO2 EMISSION MEASUREMENT BY DOAS (DIFFERENTIAL OPTICAL ABSORPTION SPECTROSCOPY AND COSPEC (CORRELATION SPECTROSCOPY AT MERAPI VOLCANO (INDONESIA

    Directory of Open Access Journals (Sweden)

    Hanik Humaida

    2010-06-01

    Full Text Available The SO2 is one of the volcanic gases that can use as indicator of volcano activity. Commonly, SO2 emission is measured by COSPEC (Correlation Spectroscopy. This equipment has several disadvantages; such as heavy, big in size, difficulty in finding spare part, and expensive. DOAS (Differential Optical Absorption Spectroscopy is a new method for SO2 emission measurement that has advantages compares to the COSPEC. Recently, this method has been developed. The SO2 gas emission measurement of Gunung Merapi by DOAS has been carried out at Kaliadem, and also by COSPEC method as comparation. The differences of the measurement result of both methods are not significant. However, the differences of minimum and maximum result of DOAS method are smaller than that of the COSPEC. It has range between 51 ton/day and 87 ton/day for DOAS and 87 ton/day and 201 ton/day for COSPEC. The measurement of SO2 gas emission evaluated with the seismicity data especially the rockfall showed the presence of the positive correlation. It may cause the gas pressure in the subsurface influencing instability of 2006 eruption lava.   Keywords: SO2 gas, Merapi, DOAS, COSPEC

  16. Satellite-based constraints on explosive SO2 release from Soufrière Hills Volcano, Montserrat

    Science.gov (United States)

    Carn, Simon A.; Prata, Fred J.

    2010-09-01

    Numerous episodes of explosive degassing have punctuated the 1995-2009 eruption of Soufrière Hills volcano (SHV), Montserrat, often following major lava dome collapses. We use ultraviolet (UV) and infrared (IR) satellite measurements to quantify sulfur dioxide (SO2) released by explosive degassing, which is not captured by routine ground-based and airborne gas monitoring. We find a total explosive SO2 release of ˜0.5 Tg, which represents ˜6% of total SO2 emissions from SHV since July 1995. The majority of this SO2 (˜0.4 Tg) was vented following the most voluminous SHV dome collapses in July 2003 and May 2006. Based on our analysis, we suggest that the SO2 burden measured following explosive disruption of lava domes depends on several factors, including the instantaneous lava effusion rate, dome height above the conduit, and the vertical component of directed explosions. Space-based SO2 measurements merit inclusion in routine gas monitoring at SHV and other dome-forming volcanoes.

  17. The effect of SO2 on the production of ethanol, acetaldehyde, organic acids, and flavor volatiles during industrial cider fermentation.

    Science.gov (United States)

    Herrero, Mónica; García, Luis A; Díaz, Mario

    2003-05-21

    SO(2) is widely used in cider fermentation but also in other alcoholic beverages such as wine. Although the authorized limit is 200 ppm total SO(2), the International Organizations recommend its total elimination or at least reduction due to health concerns. Addition of SO(2) to apple juice at levels frequently used in industrial cidermaking (100 mg/L) induced significantly higher acetaldehyde production by yeast than that obtained without SO(2). Although the practical implications of acetaldehyde evolution under cidermaking conditions has been overcome by research and few data are available, this compound reached levels in two 2000 L bioreactors that may have prevented the occurrence of simultaneous alcoholic and malolactic fermentation. It was observed that malolactic fermentation had a positive effect promoting reduction of acetaldehyde levels in cider fermented with juice, SO(2)-treated or not. The addition of SO(2) clearly delayed malolactic fermentation comparing to the control, affecting not the onset of the malolactic fermentation but the rate of malic acid degradation. This compound, however, had a stimulatory effect on alcoholic fermentation.

  18. First Observations of SO2 from the Satellite Suomi NPP OMPS: Widespread Air Pollution Events Over China

    Science.gov (United States)

    Yang, Kai; Dickerson, Russell R.; Carn, Simon A.; Ge, Cui; Wang, Jun

    2013-01-01

    Severe smog episodes over China in January 2013 received worldwide attention. This air pollution was distinguished by heavy loadings of fine particulate matter and SO2. To characterize these episodes, we employed the Ozone Mapping and Profiler Suite, Nadir Mapper (OMPS NM), an ultraviolet (UV) spectrometer flying on the Suomi National Polar-orbiting Partnership (SNPP) spacecraft since October 2011. We developed an advanced algorithm to quantify SO2 in the lower troposphere and achieved high-quality retrievals from OMPS NM, which are characterized by high precision, approx. 0.2 Dobson Units (DU; 1 DU = 2.69 x 10(exp 16) molecules/sq cm) for instantaneous field of view SO2 data and low biases (within +/-0.2 DU). Here we report SO2 retrievals and UV aerosol index data for these pollution events. The SO2 columns and the areas covered by high pollutant concentrations are quantified; the results reveal for the first time the full extent (an area of approx. 10(exp 6) sq km containing up to 60 kt of SO2) of these episodes.

  19. Involving the stakeholders in the curriculum process: a recipe for success?

    Science.gov (United States)

    Keogh, Johannes J; Fourie, Willem J; Watson, Sheona; Gay, H

    2010-01-01

    The Department of Nursing and Health Studies at the Manukau Institute of Technology (MIT) in Auckland, New Zealand, decided to involve stakeholders from the health care sector in developing a new curriculum. After implementing the new curriculum, the process was evaluated using a content analysis as qualitative research design. Seven individual interviews and one Focus group interview were conducted with the stakeholders to determine their experiences during the process. Ethical permission was sought from the MIT ethical committee. The analyses of the collected data enabled the researchers to identify six main categories. The categories were: "Existing Programme", "The need to change", "The curriculum development process", "The stakeholders", "Personnel", and "Ethnic minorities". From the collected data, it was clear that a new curriculum was necessary to enable the graduates to meet the health care needs of the New Zealand population, especially after the primary health care policy was introduced in New Zealand. It was also clear that the curriculum development process could be a painful process for all concerned, but a strong leadership could cement a feeling of "collegiality" between stakeholders and teaching staff. The importance of considering the rights of ethnic minorities is clearly stated in the Treaty of Waitangi, safeguarding the rights of the Maori People, and therefore applied rigorously in the development process. In this project, the collaborative process was very successful, and the stakeholders actually expressed feelings of "Ownership" of the curriculum.

  20. Forms And Methods Of Modern Russian Youth Involvement Into The Electoral Process

    Directory of Open Access Journals (Sweden)

    Aleksey D. Maslov

    2015-03-01

    Full Text Available In the present article authors analyzes forms and methods of modern Russian youth involvement in the electoral process. Involving young people in the electoral process is directly related to the problem of increasing the level of political culture in the society. This article presents the main forms of work to attract young people to participate in elections in our country, according to the Central Election Commission (CEC of Russia, some of the regional election commissions, the Russian Public Opinion Research Center (WCIOM. Authors note that at present there are more than one hundred and sixty legislative acts of the Russian Federation, which reflect certain aspects of the state youth policy. All these measures stimulate the political activity of young people, but in our opinion, that is not enough. The fundamental change in the attitude of young people to politics, to the institution of elections is possible only when young people feel like a real part and the subject of transformation processes in our country. In conclusion authors summarizes, that a fundamental change in the relationship of young people to politics, the institution of elections is possible only, when very young feel a real party and the subject of transformation processes in our country. This is possible only when the state is really and not formally prioritizes youth policy. Young people should have a daily state support for education, starting a business, implementation of acquired skills for a decent fee, starting a family, buying a house, etc.

  1. Smog chamber study on aging of combustion soot in isoprene/SO2/NOx system: Changes of mass, size, effective density, morphology and mixing state

    Science.gov (United States)

    Li, Kangwei; Chen, Linghong; Han, Ke; Lv, Biao; Bao, Kaiji; Wu, Xuecheng; Gao, Xiang; Cen, Kefa

    2017-02-01

    Atmospheric soot aging process is always accompanied by secondary particle formation, which is a comprehensive environmental issue that deserves great attention. On one hand, aging of primary soot could change its own physicochemical properties; on the other hand, complex air pollution caused by pollutant emission from various sources (e.g., vehicle exhausts, coal-fired flue gases and biogenic VOCs emission) may contribute to secondary particle formation onto primary particle surface. In this study, aging of combustion soot in isoprene/SO2/NOx system was investigated under controlled laboratory conditions in several smog chamber experiments. During the evolution of soot, several physical properties such as mass, size, effective density, morphology and mixing state were determined simultaneously by an integrated aerosol analytical system of Scanning Mobility Particle Sizer (SMPS), Differential Mobility Analyzer-Aerosol Particle Mass Analyzer-Condensation Particle Counter (DMA-APM-CPC) and Transmission Electron Microscopy coupled with Energy-dispersive X-ray Spectrometry (TEM/EDX) techniques. Here, based on the experimental results of soot aging under different gas-phase composition and relative humidity (RH), we firstly proposed possible aging pathways of soot in isoprene/SO2/NOx system. A synergetic effect was speculated to exist between SO2 and isoprene on soot aging process, which led to more secondary particle formation. At the same time, TEM/EDX analysis showed that a competitive mechanism between H2SO4(g) and isoprene oxidation vapor may exist: H2SO4(g) firstly condensed onto fresh soot, then an acceleration of isoprene oxidation products formed onto H2SO4 pre-coated soot. In isoprene/SO2/NOx system, high RH conditions could contribute to soot aging and new particle formation. The changes of effective density and dynamic shape factor of soot also indicated that high RH conditions could accelerate soot aging process, and led chain-like soot into more spherical

  2. NO2-initiated multiphase oxidation of SO2 by O2 on CaCO3 particles

    Science.gov (United States)

    Yu, Ting; Zhao, Defeng; Song, Xiaojuan; Zhu, Tong

    2018-05-01

    The reaction of SO2 with NO2 on the surface of aerosol particles has been suggested to be important in sulfate formation during severe air pollution episodes in China. However, we found that the direct oxidation of SO2 by NO2 was slow and might not be the main reason for sulfate formation in ambient air. In this study, we investigated the multiphase reaction of SO2 with an O2 / NO2 mixture on single CaCO3 particles using Micro-Raman spectroscopy. The reaction converted the CaCO3 particle to a Ca(NO3)2 droplet, with CaSO4 ⚫ 2H2O solid particles embedded in it, which constituted a significant fraction of the droplet volume at the end of the reaction. The reactive uptake coefficient of SO2 for sulfate formation was on the order of 10-5, which was higher than that for the multiphase reaction of SO2 directly with NO2 by 2-3 orders of magnitude. According to our observations and the literature, we found that in the multiphase reaction of SO2 with the O2 / NO2 mixture, O2 was the main oxidant of SO2 and was necessary for radical chain propagation. NO2 acted as the initiator of radical formation, but not as the main oxidant. The synergy of NO2 and O2 resulted in much faster sulfate formation than the sum of the reaction rates with NO2 and with O2 alone. We estimated that the multiphase oxidation of SO2 by O2 initiated by NO2 could be an important source of sulfate and a sink of SO2, based on the calculated lifetime of SO2 regarding the loss through the multiphase reaction versus the loss through the gas-phase reaction with OH radicals. Parameterization of the reactive uptake coefficient of the reaction observed in our laboratory for further model simulation is needed, as well as an integrated assessment based on field observations, laboratory study results, and model simulations to evaluate the importance of the reaction in ambient air during severe air pollution episodes, especially in China.

  3. Stakeholders and public involvement in river management: heterogeneous acceptance of participatory processes among Swiss institutions.

    Science.gov (United States)

    Buletti, Nora; Utz, Stephan; Ejderyan, Olivier; Graefe, Olivier; Lane, Stuart; Reynard, Emmanuel

    2014-05-01

    This research explores participatory processes in the domain of river management in Switzerland. The main objective is to better understand how participatory processes are incorporated into river management practice. Switzerland being a federal state, river management is a cantonal (regional) responsibility, under the supervision (and co-funding) of the State (a Confederation). The federal funding includes the opportunity to fund additional participatory activities to aid river management, not least because the federal authorities consider the involvement of wider stakeholders and the public in decision-making as a means of aiding the progression of projects. This is a particularly important goal in a Swiss setting where direct democracy (the possibility of calling the decision of any level of government into question through a popular vote) means that a reasonable level of project acceptance is a necessary element of project progression. River management in Switzerland now includes both flood protection and river restoration objectives, which has served to increase its controversy: river corridors contain competing interests with different objectives (e.g. ecological enhancement, protection of agricultural land, flood risk reduction). We were asked by the Confederation to evaluate participatory processes it sponsored and one element of this evaluation aimed to develop a typology of stakeholder participation. We conducted interviews with the 26 cantonal officers in charge of river management. These interviews were based upon thematically structured open ended questions, with the responses analyzed qualitatively. We have identified significant divergence in the implementation of participatory processes between the cantons. These appear to be related to two factors: (1) the canton's historical experience of river management; and (2) the methods used to select stakeholders for inclusion in the decisional process. Cantons that refer to guidelines or pre

  4. The interactive alphabet with augmented reality as a form of involving children in educational process

    Directory of Open Access Journals (Sweden)

    Vladimir D. Sekerin

    2017-01-01

    Full Text Available Research objective: to prove the expediency of using technologies with augmented reality in educational process of children in order to increase the level of their involvement and to improve the efficiency of educational process. Materials and methods. The information base of the research was made by scientific publications, information and analytical reviews, periodicals, monographs, information placed in the Internet network, concerning practical application of technologies with augmented reality in educational process, descriptive and comparative methods of analysis form the methodical basis of this research. Results. It is shown that in educational process of children it is expedient to use the modern technological achievements allowing organizing productive interactions and relationship of the students among themselves and with teachers, lecturers. Educational, business, role-playing games, discussions promoting acceleration of acquiring  a new experience and receiving new knowledge are the perspective formats of realizing the educational process. The world of augmented reality has the following properties: combines the real and virtual, interacts in real time mode, and functions in three-dimensional space. The advantages of the Interactive alphabet on the basis of the augmented reality technology are as follows: 1 security of strong emotional responses; 2 the involvement and interactivity promoting steady memorizing; 3 possibilities of interaction with the artificial world by means of gadgets; 4 Digital and offline communication; 5 possibility of carrying out virtual lessons. One of the main features of virtual reality is the feeling of participation and the opportunity to observe everything from the first person. It makes expedient to carry out lessons entirely in the virtual reality. Achievement of full involvement in educational process promotes increase of motivation and progress in knowledge acquisition.  The use of the augmented

  5. Pilot-plant for NOx, SO2, HCl removal from flue-gas of municipal waste incinerator by electron beam irradiation

    International Nuclear Information System (INIS)

    Doi, Takeshi; Suda, Shoichi; Morishige, Atsushi; Tokunaga, Okihiro; Aoki, Yasushi; Sato, Shoichi; Komiya, Mikihisa; Hashimoto, Nobuo; Nakajima, Michihiro.

    1992-01-01

    A pilot-Plant for NO x , SO 2 and HCl removal from flue-gas of municipal waste incinerator by electron beam irradiation was designed and its construction at Matsudo City Waste Disposal Center was planned. The flue-gas of 1,000 Nm 3 /hr is guided from the waste incinerator flue-gas line of 30,000 Nm 3 /hr to the Pilot-Plant to be processed by spraying Ca(OH) 2 slurry (NKK-LIMAR Process) and irradiating high-energy electron beam of an accelerator. NO x , SO 2 and HCl are removed simultaneously from the flue-gas by the enhanced reaction with Ca(OH) 2 under irradiation. According to the basic research performed using a small size reactor at TRCRE of JAERI, the electron beam irradiation process was proved to be very effective for these harmful gases removal. Based on this result, the Pilot-Plant was designed for the demonstration of NO x , SO 2 and HCl removal performance using electron accelerator of maximum energy 0.95 MeV and maximum power 15 kW. The designing and planning were promoted by NKK in cooperation with JAERI and Matsudo City. (author)

  6. Sulfomethylated lignosulfonates as additives in oil recovery processes involving chemical recovery agents

    Energy Technology Data Exchange (ETDEWEB)

    Kalfoglou, G.

    1979-10-30

    A process for producing petroleum from subterranean formations is disclosed wherein production from the formation is obtained by driving a fluid from an injection well to a production well. The process involves injecting via the injection well into the formation an aqueous solution of sulfomethylated lignosulfonate salt as a sacrificial agent to inhibit the deposition of surfactant and/or polymer on the reservoir matrix. The process may best be carried out by injecting the sulfomethylated lignosulfonates into the formation through the injection well mixed with either a polymer, a surfactant solution and/or a micellar dispersion. This mixture would then be followed by a drive fluid such as water to push the chemicals to the production well.

  7. Sulfomethylated lignosulfonates as additives in oil recovery processes involving chemical recovery agents

    Energy Technology Data Exchange (ETDEWEB)

    Kalfoglou, G.

    1981-05-26

    A process for producing petroleum from subterranean formations is disclosed wherein production from the formation is obtained by driving a fluid from an injection well to a production well. The process involves injecting via the injection well into the formation an aqueous solution of sulfomethylated lignosulfonate salt as a sacrificial agent to inhibit the deposition of surfactant and/or polymer on the reservoir matrix. The process may best be carried out by injecting the sulfomethylated lignosulfonates into the formation through the injection well mixed with either a polymer, a surfactant solution and/or a micellar dispersion. This mixture would then be followed by a drive fluid such as water to push the chemicals to the production well.

  8. Monitoring and control of amygdala neurofeedback involves distributed information processing in the human brain.

    Science.gov (United States)

    Paret, Christian; Zähringer, Jenny; Ruf, Matthias; Gerchen, Martin Fungisai; Mall, Stephanie; Hendler, Talma; Schmahl, Christian; Ende, Gabriele

    2018-03-30

    Brain-computer interfaces provide conscious access to neural activity by means of brain-derived feedback ("neurofeedback"). An individual's abilities to monitor and control feedback are two necessary processes for effective neurofeedback therapy, yet their underlying functional neuroanatomy is still being debated. In this study, healthy subjects received visual feedback from their amygdala response to negative pictures. Activation and functional connectivity were analyzed to disentangle the role of brain regions in different processes. Feedback monitoring was mapped to the thalamus, ventromedial prefrontal cortex (vmPFC), ventral striatum (VS), and rostral PFC. The VS responded to feedback corresponding to instructions while rPFC activity differentiated between conditions and predicted amygdala regulation. Control involved the lateral PFC, anterior cingulate, and insula. Monitoring and control activity overlapped in the VS and thalamus. Extending current neural models of neurofeedback, this study introduces monitoring and control of feedback as anatomically dissociated processes, and suggests their important role in voluntary neuromodulation. © 2018 Wiley Periodicals, Inc.

  9. A non-linear decision making process for public involvement in environmental management activities

    International Nuclear Information System (INIS)

    Harper, M.R.; Kastenberg, W.

    1995-01-01

    The international industrial and governmental institutions involved in radioactive waste management and environmental remediation are now entering a new era in which they must significantly expand public involvement. Thus the decision making processes formerly utilized to direct and guide these institutions must now be shifted to take into consideration the needs of many more stakeholders than ever before. To meet this challenge, they now have the job of developing and creating a new set of accurate, sufficient and continuous self-regulating and self-correcting information pathways between themselves and the many divergent stakeholder groups in order to establish sustainable, trusting and respectful relationships. In this paper the authors introduce a new set of non-linear, practical and effective strategies for interaction. These self-regulating strategies provide timely feedback to a system, establishing trust and creating a viable vehicle for staying open and responsive to the needs out of which change and balanced adaptation can continually emerge for all stakeholders. The authors present a decision making process for public involvement which is congruent with the non-linear ideas of holographic and fractal relationships -- the mutual influence between related parts of the whole and the self-symmetry of systems at every level of complexity

  10. [Characterizing spatial patterns of NO(x), SO2 and O3 in Pearl River Delta by passive sampling].

    Science.gov (United States)

    Zhao, Yang; Shao, Min; Wang, Chen; Wang, Bo-Guang; Lu, Si-Hua; Zhong, Liu-Ju

    2011-02-01

    Concentrations of NO(x), SO2 and O3 were measured by passive sampling within 200km x 200km grid in Pearl River Delta (PRD). Sampling period was two weeks in November, 2009. Spatial distributions of NO(x), SO2 and O3 were obtained by Kriging interpolation method. The results were compared with emission inventories and modeling results. The transportations of O3 were evaluated by using backward trajectories of air parcels. During the sampling period, the mean concentrations of NO(x), SO2 and O3 were 75.9 microg/m3, 37.3 microg/m3 and 36.2 microg/m3, respectively. And the highest concentrations of NO(x), SO2 and O3 were 195.7 microg/m3, 95.9 microg/m3 and 81.8 microg/m3. Comparing with routine measurements from the regional monitoring network in PRD, the results by passive method were 18.6%, 33.5% and 37.5% lower for NO(x), SO2 and O3, respectively. The spatial patterns demonstrated that higher NO(x) concentrations often appeared in cities such as Guangzhou, Foshan and Shenzhen. SO2 concentrations were higher in west and lower in east. High SO2 concentrations are mainly from emission of power plants and industrial sources. Concentrations of O3 showed the highest levels in the south of PRD. Backward trajectory analysis for higher ozone areas indicated that 53% of the air masses were from the region with high concentration of NO(x). The horizontal transportation caused higher ozone in the south while lower in north in PRD.

  11. Increased Atmospheric SO2 Detected from Changes in Leaf Physiognomy across the Triassic–Jurassic Boundary Interval of East Greenland

    Science.gov (United States)

    Bacon, Karen L.; Belcher, Claire M.; Haworth, Matthew; McElwain, Jennifer C.

    2013-01-01

    The Triassic–Jurassic boundary (Tr–J; ∼201 Ma) is marked by a doubling in the concentration of atmospheric CO2, rising temperatures, and ecosystem instability. This appears to have been driven by a major perturbation in the global carbon cycle due to massive volcanism in the Central Atlantic Magmatic Province. It is hypothesized that this volcanism also likely delivered sulphur dioxide (SO2) to the atmosphere. The role that SO2 may have played in leading to ecosystem instability at the time has not received much attention. To date, little direct evidence has been presented from the fossil record capable of implicating SO2 as a cause of plant extinctions at this time. In order to address this, we performed a physiognomic leaf analysis on well-preserved fossil leaves, including Ginkgoales, bennettites, and conifers from nine plant beds that span the Tr–J boundary at Astartekløft, East Greenland. The physiognomic responses of fossil taxa were compared to the leaf size and shape variations observed in nearest living equivalent taxa exposed to simulated palaeoatmospheric treatments in controlled environment chambers. The modern taxa showed a statistically significant increase in leaf roundness when fumigated with SO2. A similar increase in leaf roundness was also observed in the Tr–J fossil taxa immediately prior to a sudden decrease in their relative abundances at Astartekløft. This research reveals that increases in atmospheric SO2 can likely be traced in the fossil record by analyzing physiognomic changes in fossil leaves. A pattern of relative abundance decline following increased leaf roundness for all six fossil taxa investigated supports the hypothesis that SO2 had a significant role in Tr–J plant extinctions. This finding highlights that the role of SO2 in plant biodiversity declines across other major geological boundaries coinciding with global scale volcanism should be further explored using leaf physiognomy. PMID:23593262

  12. Top-down NOx and SO2 emissions simultaneously estimated from different OMI retrievals and inversion frameworks

    Science.gov (United States)

    Qu, Z.; Henze, D. K.; Wang, J.; Xu, X.; Wang, Y.

    2017-12-01

    Quantifying emissions trends of nitrogen oxides (NOx) and sulfur dioxide (SO2) is important for improving understanding of air pollution and the effectiveness of emission control strategies. We estimate long-term (2005-2016) global (2° x 2.5° resolution) and regional (North America and East Asia at 0.5° x 0.667° resolution) NOx emissions using a recently developed hybrid (mass-balance / 4D-Var) method with GEOS-Chem. NASA standard product and DOMINO retrievals of NO2 column are both used to constrain emissions; comparison of these results provides insight into regions where trends are most robust with respect to retrieval uncertainties, and highlights regions where seemingly significant trends are retrieval-specific. To incorporate chemical interactions among species, we extend our hybrid method to assimilate NO2 and SO2 observations and optimize NOx and SO2 emissions simultaneously. Due to chemical interactions, inclusion of SO2 observations leads to 30% grid-scale differences in posterior NOx emissions compared to those constrained only by NO2 observations. When assimilating and optimizing both species in pseudo observation tests, the sum of the normalized mean squared error (compared to the true emissions) of NOx and SO2 posterior emissions are 54-63% smaller than when observing/constraining a single species. NOx and SO2 emissions are also correlated through the amount of fuel combustion. To incorporate this correlation into the inversion, we optimize seven sector-specific emission scaling factors, including industry, energy, residential, aviation, transportation, shipping and agriculture. We compare posterior emissions from inversions optimizing only species' emissions, only sector-based emissions, and both species' and sector-based emissions. In situ measurements of NOx and SO2 are applied to evaluate the performance of these inversions. The impacts of the inversion on PM2.5 and O3 concentrations and premature deaths are also evaluated.

  13. Conditions for a partial summation of SO2 and NO2 hazardous effect in gas emission regulations

    Science.gov (United States)

    Sokolov, A. K.

    2017-12-01

    In order to provide environmental safety, the concentrations of SO2 and SO2 in the surface layer of atmospheric air should not exceed corresponding one-time values accepted for maximum permissible concentrations (MPCs). The only document that provides a normative calculation of hazardous substance dispersion in the atmospheric air up to the present time is presented by regulations OND-86. It has established that, in taking into account the summation (unidirectionality) of hazardous action of substances (including SO2 and NO2 gases), the sum of their relative concentrations should not exceed unity. A novel standard GN 2.1.6.2326-08 stipulates that "nitrogen dioxide and sulfur dioxide have a partial summation of action; therefore the sum of their relative concentrations should not exceed 1.6." This paper is devoted to analyzing the calculation of the summation of action for SO2 and NO2 gases and proving that the condition established in GN 2.1.6.2326-08 is not quite correct. According to the condition required by standard GN 2.1.6.2326-08, it turns out that, for some combinations of concentrations, the hazardous effect of gases is not added together, but one gas compensates an effect of the other, which contradicts the points of OND-86. For example, at SO2 and NO2 concentrations amounting to 0.6 and 0.04, respectively, the condition required by standard GN 2.1.6.2326-08 is satisfied, although the concentration of SO2 exceeds a normatively fixed value of MPC = 0.5. The graphical analysis of a concentration region for SO2 and NO2 gases clearly shows the areas where the condition required by standard GN 2.1.6.2326-08 is satisfied, but the environmental safety according to OND-86 is not provided. Recommendations are proposed for the correction of requirements established by standard GN 2.1.6.2326-08.

  14. Stake holder involvement in the Canadian review process for uranium production projects in Northern Saskatchewan

    International Nuclear Information System (INIS)

    Underhill, D.

    2004-01-01

    This report describes the Canadian environmental review process for uranium production projects as a case study for the purpose of understanding the nature and value of stakeholder involvement in the management of radiological hazards. While the Canadian review process potentially applies to any development, this case study focuses on the assessment of the uranium projects of northern Saskatchewan conducted during the 1990's. It describes the environmental assessment (EA) conducted in the 1990's for six new uranium facilities (including mines and mills and related tailings disposal sites) planned in northern Saskatchewan. Both the Canadian federal and the Saskatchewan provincial government have extensive environmental review processes that must under law be complete before any major industrial development judged to have potential environmental impacts is undertaken within their respective territories. However, even in those instances where no clear potential environmental impacts are evident, Canadian law mandates 'if public concern about the proposal is such that a public review is desirable, the initiating department shall refer the proposal to the Minister for review by a Panel'. (Wh95) As a stakeholder under law, in both Canada and Saskatchewan, the public plays an important role in the environmental review process. To encourage participation and assist the public in its review the two governments may provide funding (as done in this review) to assist qualified individuals or groups to participant in the review process. The first section of this case study sets the scene. It describes the Saskatchewan uranium mining story, focusing on how the importance of the public stakeholder evolved to become a major component, under law, in the EA process for new uranium mines. This increase in stakeholder involvement opportunities coincided with heightened public concern for the socio-economic impacts of the projects. In the late 1980's both governments were advised by

  15. EMPLOYEE INVOLVEMENT IN A CHANGE PROCESS - A CASE STUDY FOR ROMANIAN ORGANIZATIONS

    Directory of Open Access Journals (Sweden)

    Prediscan Mariana

    2015-07-01

    Full Text Available Innovation, competitive advantage, change are some concepts that should be on every organization's agenda, due to the fact the global market leads to global competition so in order to increase the market share, turnover or profit organizations have to incorporate those concepts in their strategies. The outside environment is very unstable and things are evolving very fast so managers from all levels have to acknowledge the importance of change and to identify as soon as possible several new ideas that should be the subject of different change processes. Openness to organizational change has become a mandatory feature for those organizations that want to survive and adapt to the external pressure, helping them to be efficient. Even if in many cases managers are the initiators of change, this process is very complex and needs support and involvement from all the members of the organization, so the employee's attitude and commitment to change is crucial. In many cases employees have a negative attitude towards change and manifest a strong resistance, due to the fact that they are not consulted and are not involved in the process of the identification for the need of change. Without understanding and knowing very well what it is expected from them, employees are afraid of the unknown and prefer to perform their tasks as they did before. Creating a climate and a culture for change is very important, because like this change will be something normal, continuous and people will feel comfortable with any change initiatives, without being surprised, confused or scared. Even if any change process should improve the current state of the organization, sometimes change efforts fail because the ones that resist change are stronger than the ones supporting change. The purpose of this paper is to analyze how often are Romanian employees involved in the processes of change and how important is the role they play. We have also tried to see the Romanian manager

  16. Involvement of translation and transcription processes into neurophysiological mechanisms of long-term memory reconsolidation.

    Science.gov (United States)

    Kozyrev, S A; Nikitin, V P

    2013-03-01

    We studied the involvement of translation and transcription processes into behavioral and neuronal mechanisms of reconsolidation of the long-term memory of the conditioned taste aversion in edible snails. Injection of cycloheximide (an inhibitor of protein synthesis) to the snails in 48 h after training combined with subsequent reminder and presentation of the conditional stimulus resulted in the development of persistent amnesia and depression of the responses of the defensive behavior command neurons LPl1 and RPl1 to the conditional stimulus. Injection of mRNA synthesis inhibitors actinomycin D or DRB (5,6-dichloro-1-β-D-ribofuranosylbenzimidasole) in 48 h after conditioning with subsequent reminding procedure produced no effects on memory retention and on the responses of the command neurons to the conditional stimulus. The study suggests that the proteins translated from previously synthesized and stored mRNA were involved in the mechanisms of reconsolidation of the memory responsible for conditioned taste aversion.

  17. Relevant Factors in the Process of Socialization, Involvement and Belonging of Descendants in Family Businesses

    Directory of Open Access Journals (Sweden)

    Melquicedec Lozano-Posso

    2016-12-01

    Full Text Available This research works toward the identification of the factors that comprise the process of socialization, involvement and initial belonging of descendants in family businesses and the key relationships between them. By means of a qualitative detailed study of four cases, complemented by a quantitative survey of 274 Colombian family businesses, the authors generate a new model that takes into account both factors explored in previous research as well as others identified in this study. Findings confirm the specific dependency of each stage on the subsequent ones; socialization influences involvement, which in turn influences the belonging of the descendants to the family business, with a strong presence of factors such as knowledge, leadership, mode, timing, and motivation. Those responsible for the orientation of potential successors may examine these findings in order to optimize their preparation efforts and support of family human resources for the continuity of the business.

  18. The insula is not specifically involved in disgust processing: an fMRI study.

    Science.gov (United States)

    Schienle, A; Stark, R; Walter, B; Blecker, C; Ott, U; Kirsch, P; Sammer, G; Vaitl, D

    2002-11-15

    fMRI studies have shown that the perception of facial disgust expressions specifically activates the insula. The present fMRI study investigated whether this structure is also involved in the processing of visual stimuli depicting non-mimic disgust elicitors compared to fear-inducing and neutral scenes. Twelve female subjects were scanned while viewing alternating blocks of 40 disgust-inducing, 40 fear-inducing and 40 affectively neutral pictures, shown for 1.5 s each. Afterwards, affective ratings were assessed. The disgust pictures, rated as highly repulsive, induced activation in the insula, the amygdala, the orbitofrontal and occipito-temporal cortex. Since during the fear condition the insula was also involved, our findings do not fit the idea of the insula as a specific disgust processor.

  19. A quality assurance program for environmental data operations involving waste management processes

    International Nuclear Information System (INIS)

    Johnson, G.L.; Blacker, S.M.

    1990-01-01

    This paper describes the 'core' elements needed in an effective Quality Program for environmental data operations involving nuclear, mixed, or non-nuclear wastes. For each core element, this paper examines the minimum components needed for an effective Quality Program for EDOs, and compares approaches to Quality Programs currently required by the U.S. DOE and the U.S. EPA. The comparison suggests how the Quality Program requirements used at DOE, and defined by NQA-1 and its supplements, and those used by EPA through its QAMS program guidance, may provide a basis for developing a harmonized Quality Program for EDOs involving any waste management processes, nuclear, non-nuclear, or mixed. (orig./DG)

  20. APP processing and the APP-KPI domain involvement in the amyloid cascade.

    Science.gov (United States)

    Menéndez-González, M; Pérez-Pinera, P; Martínez-Rivera, M; Calatayud, M T; Blázquez Menes, B

    2005-01-01

    Alternative APP mRNA splicing can generate isoforms of APP containing a Kunitz protease inhibitor (KPI) domain. KPI is one of the main serine protease inhibitors. Protein and mRNA KPI(+)APP levels are elevated in Alzheimer's disease (AD) brain and are associated with increased amyloid beta deposition. In the last years increasing evidence on multiple points in the amyloid cascade where KPI(+)APP is involved has been accumulated, admitting an outstanding position in the pathogenesis of AD to the KPI domain. This review focuses on the APP processing, the molecular activity of KPI and its physiological and pathological roles and the KPI involvement in the amyloid cascade through the nerve growth factor, the lipoprotein receptor-related protein, the tumor necrosis factor-alpha converting enzyme and the Notch1 protein.

  1. Time Series of SO2 Flux from Popocatépetl Volcano by an Ultra-Violet Camera with a Set of Different Band-Pass Filters

    Science.gov (United States)

    Schiavo, B.; Stremme, W.; Grutter, M.; Campion, R.; Rivera, C. I.; Inguaggiato, S.

    2017-12-01

    The measurement of SO2flux from active volcanoes are of great importance, for monitoring and hazard of volcanic activity, environmental impact and flux emissions related to changes of magmatic activity. Sulfur dioxide total flux from Popocatépetl volcano was determinad using a ultra-violet camera (or SO2 camera) with different band-pass filter. The flux is obteined from the product of the gas concentration over integrated the plume cross-section (slant column in molec/cm2 or ppm*m) and wind velocity data. Model of plume altitude and wind speed measurement are used to calculate a wind velocity, but a new method of sequential images is widely used in several years for this calculation. Volcanic plume measurements, for a total of about 60 days from from January to March 2017, were collected and utilized to generate the SO2 time series. The importance of monitoring and the time series of volcanic gas emissions is described and proven by many scientific studies. A time series of the Popocatépetl volcano will allow us to detect the volcanic gas as well as anomalies in volcanic processes and help to estimate the average SO2 flux of the volcano. We present a detailed description of the posterior correction of the dilution effect, which occurs due to a simplification of the radiative transfer equation. The correction scheme is especial applicable for long term monitoring from a permanent observation site. Images of volcanic SO2 plumes from the active Popocatépetl volcano in Mexico are presented, showing persistent passive degassing. The measurment are taken from the Altzomoni Atmospheric Observatory (19.12N, -98.65W, 3,985 m.a.s.l.), which forms part of the RUOA (www.ruoa.unam.mx) and NDACC (https://www2.acom.ucar.edu/irwg) networks. It is located north of the crater at 11 km distance. The data to calculate SO2 flux (t/d or kg/s) were recorded with the QSI UV camera and processed using Python scripts.

  2. A process for integrating public involvement into technical/social programs

    International Nuclear Information System (INIS)

    Wiltshire, S.; Williams, C.

    1994-01-01

    Good technical/social decisions--those that are technically sound and publicly acceptable--result from a planning process that considers consulting the public a basic part of the technical program, as basic as hiring a technical consultant to advise about new ideas in computer modeling. This paper describes a specific process for making public involvement an integral part of decision-making about high-level radioactive waste management, so that important technical, social, environmental, economic, and cultural information and values can be incorporated in a meaningful way in planning and carrying out a high-level waste management program or project. The process for integration must consider: (a) the decision or task for which public interaction is needed; (b) the people who should or will want to participate in the decision or task; (c) the goals or purposes of the communication or interaction--the agency's and the public's; (d) the kinds of information the public needs and that the agency needs in order to understand the relevant technical and social issues; and (e) the types of communication or involvement that best serve to meet the agency's and the public's goals

  3. Involvement of microRNAs in physiological and pathological processes in the lung

    Directory of Open Access Journals (Sweden)

    Kriegova Eva

    2010-11-01

    Full Text Available Abstract To date, at least 900 different microRNA (miRNA genes have been discovered in the human genome. These short, single-stranded RNA molecules originate from larger precursor molecules that fold to produce hairpin structures, which are subsequently processed by ribonucleases Drosha/Pasha and Dicer to form mature miRNAs. MiRNAs play role in the posttranscriptional regulation of about one third of human genes, mainly via degradation of target mRNAs. Whereas the target mRNAs are often involved in the regulation of diverse physiological processes ranging from developmental timing to apoptosis, miRNAs have a strong potential to regulate fundamental biological processes also in the lung compartment. However, the knowledge of the role of miRNAs in physiological and pathological conditions in the lung is still limited. This review, therefore, summarizes current knowledge of the mechanism, function of miRNAs and their contribution to lung development and homeostasis. Besides the involvement of miRNAs in pulmonary physiological conditions, there is evidence that abnormal miRNA expression may lead to pathological processes and development of various pulmonary diseases. Next, the review describes current state-of-art on the miRNA expression profiles in smoking-related diseases including lung cancerogenesis, in immune system mediated pulmonary diseases and fibrotic processes in the lung. From the current research it is evident that miRNAs may play role in the posttranscriptional regulation of key genes in human pulmonary diseases. Further studies are, therefore, necessary to explore miRNA expression profiles and their association with target mRNAs in human pulmonary diseases.

  4. Adolescent fathers: knowledge of and involvement in the breast feeding process in Brazil.

    Science.gov (United States)

    Torres de Lacerda, Ana Catarina; Lucena de Vasconcelos, Maria Gorete; Nascimento de Alencar, Eloine; Osório, Mônica Maria; Pontes, Cleide Maria

    2014-03-01

    to understand the ways in which adolescent fathers participate in the breast feeding process in the family environment in North-eastern Brazil. a descriptive, exploratory, qualitative study was undertaken involving 10 couples with infants aged 6-8 months living in a single community in Recife, Pernambuco, Brazil. Data were collected using semi-structured interviews with questions to guide the interviewer. Data were analysed using thematic content analysis, and interpreted under the theoretical reference of being an adolescent father within the context of breast feeding. from the data collected, three themes were identified: knowledge of the benefits of breast feeding for the child's health; discontinued participation of the father in breast feeding during the pregnancy-childbearing cycle; and exclusion of the adolescent father from the breast feeding process. The adolescent fathers knew about the benefits of breast feeding in terms of the child's health, but did not mention benefits for the mother, the family or society. For some adolescent fathers, their participation in the breast feeding process started during pregnancy, whereas for others, it was only initiated after the infant was born. One of the fathers was prevented, by his wife and mother-in-law, from participating in the breast feeding process. the involvement of adolescent fathers in the breast feeding process oscillated during the pregnancy-childbearing cycle. This may be due to the patriarchal cultural heritage, Brazilian paternity laws, and the fact that these fathers were adolescents. This study showed that adolescent parents were knowledgeable about breast feeding. Finally, fathers want a new model of parenting in which the man participates in child care. Crown Copyright © 2013. Published by Elsevier Ltd. All rights reserved.

  5. Genes involved in complex adaptive processes tend to have highly conserved upstream regions in mammalian genomes

    Directory of Open Access Journals (Sweden)

    Kohane Isaac

    2005-11-01

    Full Text Available Abstract Background Recent advances in genome sequencing suggest a remarkable conservation in gene content of mammalian organisms. The similarity in gene repertoire present in different organisms has increased interest in studying regulatory mechanisms of gene expression aimed at elucidating the differences in phenotypes. In particular, a proximal promoter region contains a large number of regulatory elements that control the expression of its downstream gene. Although many studies have focused on identification of these elements, a broader picture on the complexity of transcriptional regulation of different biological processes has not been addressed in mammals. The regulatory complexity may strongly correlate with gene function, as different evolutionary forces must act on the regulatory systems under different biological conditions. We investigate this hypothesis by comparing the conservation of promoters upstream of genes classified in different functional categories. Results By conducting a rank correlation analysis between functional annotation and upstream sequence alignment scores obtained by human-mouse and human-dog comparison, we found a significantly greater conservation of the upstream sequence of genes involved in development, cell communication, neural functions and signaling processes than those involved in more basic processes shared with unicellular organisms such as metabolism and ribosomal function. This observation persists after controlling for G+C content. Considering conservation as a functional signature, we hypothesize a higher density of cis-regulatory elements upstream of genes participating in complex and adaptive processes. Conclusion We identified a class of functions that are associated with either high or low promoter conservation in mammals. We detected a significant tendency that points to complex and adaptive processes were associated with higher promoter conservation, despite the fact that they have emerged

  6. Emotion and attention interactions in social cognition: brain regions involved in processing anger prosody.

    Science.gov (United States)

    Sander, David; Grandjean, Didier; Pourtois, Gilles; Schwartz, Sophie; Seghier, Mohamed L; Scherer, Klaus R; Vuilleumier, Patrik

    2005-12-01

    Multiple levels of processing are thought to be involved in the appraisal of emotionally relevant events, with some processes being engaged relatively independently of attention, whereas other processes may depend on attention and current task goals or context. We conducted an event-related fMRI experiment to examine how processing angry voice prosody, an affectively and socially salient signal, is modulated by voluntary attention. To manipulate attention orthogonally to emotional prosody, we used a dichotic listening paradigm in which meaningless utterances, pronounced with either angry or neutral prosody, were presented simultaneously to both ears on each trial. In two successive blocks, participants selectively attended to either the left or right ear and performed a gender-decision on the voice heard on the target side. Our results revealed a functional dissociation between different brain areas. Whereas the right amygdala and bilateral superior temporal sulcus responded to anger prosody irrespective of whether it was heard from a to-be-attended or to-be-ignored voice, the orbitofrontal cortex and the cuneus in medial occipital cortex showed greater activation to the same emotional stimuli when the angry voice was to-be-attended rather than to-be-ignored. Furthermore, regression analyses revealed a strong correlation between orbitofrontal regions and sensitivity on a behavioral inhibition scale measuring proneness to anxiety reactions. Our results underscore the importance of emotion and attention interactions in social cognition by demonstrating that multiple levels of processing are involved in the appraisal of emotionally relevant cues in voices, and by showing a modulation of some emotional responses by both the current task-demands and individual differences.

  7. Effects of NOx and SO2 on the secondary organic aerosol formation from photooxidation of α-pinene and limonene

    Directory of Open Access Journals (Sweden)

    D. Zhao

    2018-02-01

    Full Text Available Anthropogenic emissions such as NOx and SO2 influence the biogenic secondary organic aerosol (SOA formation, but detailed mechanisms and effects are still elusive. We studied the effects of NOx and SO2 on the SOA formation from the photooxidation of α-pinene and limonene at ambient relevant NOx and SO2 concentrations (NOx: < 1to 20 ppb, SO2: < 0.05 to 15 ppb. In these experiments, monoterpene oxidation was dominated by OH oxidation. We found that SO2 induced nucleation and enhanced SOA mass formation. NOx strongly suppressed not only new particle formation but also SOA mass yield. However, in the presence of SO2 which induced a high number concentration of particles after oxidation to H2SO4, the suppression of the mass yield of SOA by NOx was completely or partly compensated for. This indicates that the suppression of SOA yield by NOx was largely due to the suppressed new particle formation, leading to a lack of particle surface for the organics to condense on and thus a significant influence of vapor wall loss on SOA mass yield. By compensating for the suppressing effect on nucleation of NOx, SO2 also compensated for the suppressing effect on SOA yield. Aerosol mass spectrometer data show that increasing NOx enhanced nitrate formation. The majority of the nitrate was organic nitrate (57–77 %, even in low-NOx conditions (<  ∼  1 ppb. Organic nitrate contributed 7–26 % of total organics assuming a molecular weight of 200 g mol−1. SOA from α-pinene photooxidation at high NOx had a generally lower hydrogen to carbon ratio (H ∕ C, compared to low NOx. The NOx dependence of the chemical composition can be attributed to the NOx dependence of the branching ratio of the RO2 loss reactions, leading to a lower fraction of organic hydroperoxides and higher fractions of organic nitrates at high NOx. While NOx suppressed new particle formation and SOA mass formation, SO2 can compensate for such effects, and the

  8. Cellular processes involved in human epidermal cells exposed to extremely low frequency electric fields.

    Science.gov (United States)

    Collard, J-F; Hinsenkamp, M

    2015-05-01

    We observed on different tissues and organisms a biological response after exposure to pulsed low frequency and low amplitude electric or electromagnetic fields but the precise mechanism of cell response remains unknown. The aim of this publication is to understand, using bioinformatics, the biological relevance of processes involved in the modification of gene expression. The list of genes analyzed was obtained after microarray protocol realized on cultures of human epidermal explants growing on deepidermized human skin exposed to a pulsed low frequency electric field. The directed acyclic graph on a WebGestalt Gene Ontology module shows six categories under the biological process root: "biological regulation", "cellular process", "cell proliferation", "death", "metabolic process" and "response to stimulus". Enriched derived categories are coherent with the type of in vitro culture, the stimulation protocol or with the previous results showing a decrease of cell proliferation and an increase of differentiation. The Kegg module on WebGestalt has highlighted "cell cycle" and "p53 signaling pathway" as significantly involved. The Kegg website brings out interactions between FoxO, MAPK, JNK, p53, p38, PI3K/Akt, Wnt, mTor or NF-KappaB. Some genes expressed by the stimulation are known to have an exclusive function on these pathways. Analyses performed with Pathway Studio linked cell proliferation, cell differentiation, apoptosis, cell cycle, mitosis, cell death etc. with our microarrays results. Medline citation generated by the software and the fold change variation confirms a diminution of the proliferation, activation of the differentiation and a less well-defined role of apoptosis or wound healing. Wnt and DKK functional classes, DKK1, MACF1, ATF3, MME, TXNRD1, and BMP-2 genes proposed in previous publications after a manual analysis are also highlighted with other genes after Pathway Studio automatic procedure. Finally, an analysis conducted on a list of genes

  9. Treatment of toxic gases SO2 and NO X by electron beam irradiation

    International Nuclear Information System (INIS)

    Castro Rubio Poli, D. de; Vieira, J.M.; Campos, C.A. de.

    1993-01-01

    The removal of S O 2 and N O x by electron beam irradiation will be studied using a small scale flow system which is being set up in order to obtain basic data for the process technical and economical feasibility concerning industrial applications. The gas irradiation will be performed using a Electron Beam Accelerator with 1,5 MeV power, 25 m A current from Radiation Dynamics, Inc. USA. (author)

  10. In-Situ Detection of SO2 Plumes in Costa Rica from Turrialba Volcano using Balloon-borne Sondes

    Science.gov (United States)

    Diaz, J. A.; Selkirk, H. B.; Morris, G. A.; Krotkov, N. A.; Pieri, D. C.; Corrales, E.

    2012-12-01

    The Turrialba Volcano near San Jose, Costa Rica regularly emits plumes containing SO2. These plumes have been detected by the Ozone Monitoring Instrument (OMI), and evidence of these plumes has also appeared in the in-situ Ticosonde project record: a continuous balloon-borne ozonesonde launch experiment conducted in a weekly basis in Costa Rica. In the case of the latter, the interference reaction of SO2 in the cathode cell of the standard electrochemical concentration cell (ECC) ozonesonde results in apparent "notches" in the ozone profile at the altitudes of the plume. In this paper, we present an overview of the Ticosonde observations and correlate the appearance of the notches with air mass back trajectory calculations that link the profiles features to emissions from the volcano. In addition, during February 2012, we deployed the dual O3/SO2 sonde from the University of Costa Rica and detected a plume of SO2 linked by back trajectory calcluations to Turrialba as well as an urban plume resulting from diesel exhaust in the boundary layer. The integrated column SO2 from the sonde profile data agree well with the OMI overpass data for this event. Data from a tethersonde measurement two days prior to the dual sonde reveal concentrations at the ppm level at the volcanic source.

  11. VizieR Online Data Catalog: Collisional excitation of sulfur dioxide, SO2, in cold molecular c

    Science.gov (United States)

    Cernicharo, J.; Spielfiedel, A.; Balanca, C.; Dayou, F.; Senent, M.-L.; Feautrier, N.; Faure, A.; Cressiot-Vincent, L.; Wiesenfeld, L.; Pardo, J. R.

    We present collisional rate coefficients for SO2 with ortho an molecular hydrogen for the physical conditions prevailing in dark molecular clouds. Rate coefficients for the first 31 rotational levels of this species (energies up to 55K) and for temperatures between 5 and 30K are provided. We have found that these rate coefficients are about ten times more than those previously computed for SO2 with helium. We calculated the expected emission of the centimeter wavelength lines of SO2. We find that the transition connecting the metastable 202 level with the 111 one is in absorption against the cosmic background for a wide range of densities. The 404-313 line is found to be inverted for densities below a few 104cm-3. We observed the 111-202 transition with the 100m Green Bank Telescope towards some dark clouds. The line is observed, as expected, in absorption and provides an abundance of SO2 in these objects of a few 10-10^. The potential use of millimeter lines of SO2 as tracers of the physical conditions of dark clouds is discussed. (3 data files).

  12. A performance study of simultaneous microbial removal of no and SO2 in a biotrickling-filter under anaerobic condition

    Directory of Open Access Journals (Sweden)

    Yaqiong Han

    2011-06-01

    Full Text Available The behaviors of simultaneous removal of NO and SO2 using the coculture of anaerobic denitrifying bacteria and sulfate reducing bacteria was investigated in a bench-scale biotrickling-filter. When the combined NO/SO2 removal biotrickling-filter was operated at an empty bed residence time of 76 s with NO and SO2 feed concentrations of 2 and 2 g/m3, respectively, the SO2 removal efficiency was always above 95%, while NO removal exhibited an evident periodicity of 5-6 days for the initial 60 days after the attachment phase. A steady-state NO-removal efficiency of around 90% was obtained after 130 days of continuous operation. Experimental results indicated that the coculture in the combined NO/SO2 removal biotrickling-filter showed a higher resistance to shock NO-loadings and a better tolerance to starvation than the single denitrifying bacteria in the NO removal biotrickling-filter.

  13. Experimental investigation of adsorption of NO and SO2 on modified activated carbon sorbent from flue gases

    International Nuclear Information System (INIS)

    Zhu, J.L.; Wang, Y.H.; Zhang, J.C.; Ma, R.Y.

    2005-01-01

    It is indicated that modified carbon is a practical sorbent for removal of NO and SO 2 from waste gases by the adsorption method. The ideal compositions for the prepared sorbent were 4.0 wt.% and 2.5 wt.% Na 2 CO 3 and KOH at the experimental conditions, respectively, shortened as ACNaK 2.5 . Experimental investigation showed that the sorbent had a comparatively high breakthrough adsorption capacity of NO and SO 2 , about 5.8 g (NO + SO 2 )/100 g sorbent. It is indicated that a relatively high adsorption temperature would benefit the sorbent adsorption capacities on NO and SO 2 at a certain space velocity and pressure. Further study revealed that the ACNaK 2.5 sorbent had good regenerability at the experimental conditions, which implied that the ACNaK 2.5 sorbent would be a useful sorbent for simultaneous removal of NO and SO 2 from waste gases by adsorption

  14. Volcanic Ash and SO2 retrievals using synthetic MODIS TIR data: comparison between inversion procedures and sensitivity analysis

    Directory of Open Access Journals (Sweden)

    Stefano Corradini

    2015-02-01

    Full Text Available In this work the volcanic ash and SO2 retrievals obtained by applying three different procedures (LUT - Look Up Table, NN - Neural Network and VPR - Volcanic Plume Removal on MODIS Thermal InfraRed (TIR synthetic measurements have been compared. The synthetic measurements are generated using MODTRAN Radiative Transfer Model (RTM for defined volcanic cloud configurations. The results, presented as the percentage difference between the retrieved ash and SO2 total masses and the true values used for the synthetic data generation, indicate maximum differences of +/- 15% and +/- 10% for all the procedures and for ash and SO2 retrievals respectively. A sensitivity analysis has been also realized to investigate the influence of volcanic cloud altitude and water vapour profile on SO2 retrievals at 7.3 and 8.6 μm. Results confirm the high sensitivity of the 7.3 μm retrieval to the volcanic cloud altitude and show that the SO2 total masses estimated at 7.3 and 8.6 μm separately can be used to improve the information on the plume height. Finally, the water vapour profile is used to compute the minimum altitude over which the 7.3 μm retrieval is effective. 

  15. Selection of best impregnated palm shell activated carbon (PSAC) for simultaneous removal of SO2 and NOx

    International Nuclear Information System (INIS)

    Sumathi, S.; Bhatia, S.; Lee, K.T.; Mohamed, A.R.

    2010-01-01

    This work examines the impregnated carbon-based sorbents for simultaneous removal of SO 2 and NOx from simulated flue gas. The carbon-based sorbents were prepared using palm shell activated carbon (PSAC) impregnated with several metal oxides (Ni, V, Fe and Ce). The removal of SO 2 and NOx from the simulated flue gas was investigated in a fixed-bed reactor. The results showed that PSAC impregnated with CeO 2 (PSAC-Ce) reported the highest sorption capacity among other impregnated metal oxides for the simultaneous removal of SO 2 and NOx. PSAC-Ce showed the longest breakthrough time of 165 and 115 min for SO 2 and NOx, respectively. The properties of the pure and impregnated PSAC were analyzed by BET, FTIR and XRF. The physical-chemical features of the PSAC-Ce sorbent indicated a catalytic activity in both the sorption of SO 2 and NOx. The formation of both sulfate (SO 4 2- ) and nitrate (NO 3- ) species on spent PSAC-Ce further prove the catalytic role played by CeO 2 .

  16. ADVANCED BYPRODUCT RECOVERY: DIRECT CATALYTIC REDUCTION OF SO2 TO ELEMENTAL SULFUR; FINAL

    International Nuclear Information System (INIS)

    Robert S. Weber

    1999-01-01

    Arthur D. Little, Inc., together with its commercialization partner, Engelhard Corporation, and its university partner Tufts, investigated a single-step process for direct, catalytic reduction of sulfur dioxide from regenerable flue gas desulfurization processes to the more valuable elemental sulfur by-product. This development built on recently demonstrated SO(sub 2)-reduction catalyst performance at Tufts University on a DOE-sponsored program and is, in principle, applicable to processing of regenerator off-gases from all regenerable SO(sub 2)-control processes. In this program, laboratory-scale catalyst optimization work at Tufts was combined with supported catalyst formulation work at Engelhard, bench-scale supported catalyst testing at Arthur D. Little and market assessments, also by Arthur D. Little. Objectives included identification and performance evaluation of a catalyst which is robust and flexible with regard to choice of reducing gas. The catalyst formulation was improved significantly over the course of this work owing to the identification of a number of underlying phenomena that tended to reduce catalyst selectivity. The most promising catalysts discovered in the bench-scale tests at Tufts were transformed into monolith-supported catalysts at Engelhard. These catalyst samples were tested at larger scale at Arthur D. Little, where the laboratory-scale results were confirmed, namely that the catalysts do effectively reduce sulfur dioxide to elemental sulfur when operated under appropriate levels of conversion and in conditions that do not contain too much water or hydrogen. Ways to overcome those limitations were suggested by the laboratory results. Nonetheless, at the end of Phase I, the catalysts did not exhibit the very stringent levels of activity or selectivity that would have permitted ready scale-up to pilot or commercial operation. Therefore, we chose not to pursue Phase II of this work which would have included further bench-scale testing

  17. ADVANCED BYPRODUCT RECOVERY: DIRECT CATALYTIC REDUCTION OF SO2 TO ELEMENTAL SULFUR

    Energy Technology Data Exchange (ETDEWEB)

    Robert S. Weber

    1999-05-01

    Arthur D. Little, Inc., together with its commercialization partner, Engelhard Corporation, and its university partner Tufts, investigated a single-step process for direct, catalytic reduction of sulfur dioxide from regenerable flue gas desulfurization processes to the more valuable elemental sulfur by-product. This development built on recently demonstrated SO{sub 2}-reduction catalyst performance at Tufts University on a DOE-sponsored program and is, in principle, applicable to processing of regenerator off-gases from all regenerable SO{sub 2}-control processes. In this program, laboratory-scale catalyst optimization work at Tufts was combined with supported catalyst formulation work at Engelhard, bench-scale supported catalyst testing at Arthur D. Little and market assessments, also by Arthur D. Little. Objectives included identification and performance evaluation of a catalyst which is robust and flexible with regard to choice of reducing gas. The catalyst formulation was improved significantly over the course of this work owing to the identification of a number of underlying phenomena that tended to reduce catalyst selectivity. The most promising catalysts discovered in the bench-scale tests at Tufts were transformed into monolith-supported catalysts at Engelhard. These catalyst samples were tested at larger scale at Arthur D. Little, where the laboratory-scale results were confirmed, namely that the catalysts do effectively reduce sulfur dioxide to elemental sulfur when operated under appropriate levels of conversion and in conditions that do not contain too much water or hydrogen. Ways to overcome those limitations were suggested by the laboratory results. Nonetheless, at the end of Phase I, the catalysts did not exhibit the very stringent levels of activity or selectivity that would have permitted ready scale-up to pilot or commercial operation. Therefore, we chose not to pursue Phase II of this work which would have included further bench-scale testing

  18. The Clean Coal Technology Program: Options for SO2, NOx, and particulate control

    International Nuclear Information System (INIS)

    Strakey, J.P.; Hargis, R.; Eastman, M.L.; Santore, R.R.

    1992-01-01

    There are currently 42 active projects in the Clean Coal Technology Program. The Pittsburgh Energy Technology Center (PETC) is responsible for managing 30 of these projects: five projects under Clean Coal 1, ten projects under Clean Coal 2, nine projects under Clean Coal 3, and six projects under Clean Coal 4. This paper describes each of the PETC projects, including the technologies involved and the project status. Many of the projects will use advanced approaches to meet current and future requirements for particulate and air toxic emissions. Discussion of these aspects have been expanded in this summary paper to address the focus of this symposium. Additional information can be provided to interested particles either through DOE, the participant or the technology supplier. Numerous non-federal organizations including state and utility/industry research groups provide important co-funding and other support for these CCT projects. Space limitations prohibit listing them in this paper; however, a complete listing can be found in the Clean Coal Technology Demonstration Program Update 1990. Appendix A to this paper contains flow diagrams for all the projects

  19. Reflective processes and competencies involved in teaching practice at university: a case study

    Directory of Open Access Journals (Sweden)

    Caetano da Costa

    2010-01-01

    Full Text Available Founded on practical rationality, this qualitative case study aimed to explore the teaching practice at university, focusing on teacher's reflections and competencies. To this end, teaching practices were described, analyzed, and interpreted. These interactions with students on a course in the pharmacy program, brought about situations involving dilemmas and learning opportunities for problem-solving and decision-making skills. Throughout the study, students were encouraged to use knowledge-in-action, reflection-in-action, and reflection-on-action, and these processes were also experienced by the teacher. Analysis of the records from classroom observation and the interviews with students and the teacher showed the fundamental role of such reflective processes, which led to attainment of the intended objectives. In this sense, the teacher's reflective practice was essential for supporting the application of each curricular component of the course.

  20. A Traveller Information System: Minimisation of the Number of Graphs’ Nodes Involved When Processing Route Requests

    Directory of Open Access Journals (Sweden)

    Bendaoud Zakaria

    2014-12-01

    Full Text Available The number of people using public transport is continuously increasing. Transport companies want to fulfil travellers’ expectations wherever possible. However, the great number of public transport companies operating in the same area can sometimes confuse travellers as to which route they should take and how to obtain the information relative to their journey. In this paper we suggest integrating several traveller information systems from different companies into the same multimodal information system, offering companies the choice not to share their data. This encourages them to join the system. Additionally, we have minimised the number of nodes involved when processing travellers’ requests in order to simplify the calculation process. To put our plan into action, we have opted for a multi-agent system coupled with the Voronoi decomposition for managing the network.

  1. Qualified public involvement in the decision making process of siting a waste repository

    International Nuclear Information System (INIS)

    Rodrigues, Danielle Monegalha; Almeida, Ivan Pedro Salati de

    2009-01-01

    The main objective of this paper is to identify the most important characteristics required for the qualification of local communities for participating in the process of defining a specific site for a radioactive waste repository. It also compares the strategies used by Hungary, United Kingdom and Belgium to stimulate the public participation in the decision-making process of building and operating a radioactive waste repository, considering both the stepwise process and the spontaneous candidacy. Two main aspects are discussed as prerequisites to constitute a qualified public. The first aspect is how well the person or entity can be considered an effective representative of the community affected by the repository. This means the conditions the representative has to speak on behalf of the community and participate in the decision making process as its voice. The second characteristic is the level and quality of the information that the community and its representatives must have to participate actively in the decision-making process and what can be done to improve this status. Referring to the strategy to public involvement, this paper discusses the importance of transparency in the process, aiming the credibility of the entrepreneur as the first pace to gaining the confidence of the public affected by the project. Implementing an open dialog and listening to the needs and claims of the population are the first steps to being accepted as a true partner of the community. Preliminary discussions and explanations are important to introduce the subject and to reduce beliefs of false threats in the affected community. The constitution of a local committee is suggested, to act as a legal and formal channel to facilitate the partnership between local community, neighbors and the entrepreneur in order to achieve a positive result in the whole process. (author)

  2. The effect of coal-fired power-plant SO2 and NOx control technologies on aerosol nucleation in the source plumes

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