[Exploratory study of air quality in elementary schools, Coimbra, Portugal].

PubMed

Ferreira, Ana Maria Conceiçã; Cardoso, Salvador Massano

2013-12-01

To analyze the air quality in elementary schools and their structural and functional conditions. Air quality in 51 elementary schools (81 classrooms) in the city of Coimbra, Portugal, both inside and outside of the rooms was evaluated during the four seasons, from 2010 to 2011. Temperature (T°), relative humidity (Hr), concentrations of carbon monoxide (CO), carbon dioxide (CO2), ozone (O3), nitrogen dioxide (NO2), sulfur dioxide (SO2), compounds were evaluated, as were volatile organics (VOC), formaldehyde and particulate matter (PM10), from November 2010 to February 2011 (autumn/winter) and March 2011 to June 2011 (spring/summer). A grid characterizing the structural and functional conditions of the schools was created. The statistical Student t test for paired samples and the Wilcoxon t test were applied. In 47 schools, the average CO2 concentrations were above the maximum reference concentration (984 ppm) mentioned in Portuguese legislation. The maximum concentration values found inside the rooms were critical, especially in the fall/winter (5,320 ppm). In some schools the average concentrations of VOC and PM10 within the maximum concentration exceeded the reference legislated. The values (risk) of CO, formaldehyde, NO2, SO2 and O3 detected were not relevant. There was a higher concentration of pollutants inside the rooms compared with outside. Inadequate ventilation is associated with high CO2 concentration in the classroom.

Conditions for a partial summation of SO2 and NO2 hazardous effect in gas emission regulations

NASA Astrophysics Data System (ADS)

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.

EVALUATION OF SIMULTANEOUS SO2/NOX CONTROL TECHNOLOGY

EPA Science Inventory

The report gives results of work concentrating on characterizing three process operational parameters of a technology that combines sorbent injection and selective non-catalytic reduction for simultaneous sulfur dioxide/nitrogen oxide (SO2/NOx) removal from coal-fired industrial ...

Simultaneous removal of sulfur dioxide and polycyclic aromatic hydrocarbons from incineration flue gas using activated carbon fibers.

PubMed

Liu, Zhen-Shu; Li, Wen-Kai; Hung, Ming-Jui

2014-09-01

Incineration flue gas contains polycyclic aromatic hydrocarbons (PAHs) and sulfur dioxide (SO2). The effects of SO2 concentration (0, 350, 750, and 1000 ppm), reaction temperature (160, 200, and 280 degrees C), and the type of activated carbon fibers (ACFs) on the removal of SO2 and PAHs by ACFs were examined in this study. A fluidized bed incinerator was used to simulate practical incineration flue gas. It was found that the presence of SO2 in the incineration flue gas could drastically decrease removal of PAHs because of competitive adsorption. The effect of rise in the reaction temperature from 160 to 280 degrees C on removal of PAHs was greater than that on SO2 removal at an SO2 concentration of 750 ppm. Among the three ACFs studied, ACF-B, with the highest microporous volume, highest O content, and the tightest structure, was the best adsorbent for removing SO2 and PAHs when these gases coexisted in the incineration flue gas. Implications: Simultaneous adsorption of sulfur dioxide (SO2) and polycyclic aromatic hydrocarbons (PAHs) emitted from incineration flue gas onto activated carbon fibers (ACFs) meant to devise a new technique showed that the presence of SO2 in the incineration flue gas leads to a drastic decrease in removal of PAHs because of competitive adsorption. Reaction temperature had a greater influence on PAHs removal than on SO2 removal. ACF-B, with the highest microporous volume, highest O content, and tightest structure among the three studied ACFs, was found to be the best adsorbent for removing SO2 and PAHs.

Influence of sulfur dioxide on the respiratory system of Miyakejima adult residents 6 years after returning to the island.

PubMed

Kochi, Takeshi; Iwasawa, Satoko; Nakano, Makiko; Tsuboi, Tazuru; Tanaka, Shigeru; Kitamura, Hiroko; Wilson, Donald John; Takebayashi, Toru; Omae, Kazuyuki

2017-07-27

Mount Oyama, on the Japanese island of Miyakejima, began erupting in June 2000, necessitating the evacuation of 3,000 island residents. Volcanic gas emissions, primarily consisting of sulfur dioxide (SO 2 ), gradually decreased and residents returned to the island after the evacuation order was lifted in February 2005. To assess the exposure-effect and exposure-response relationships between SO 2 exposure and effects on respiratory system in adult Miyakejima residents. Health checkups focusing on pulmonary function and respiratory/irritative symptoms were conducted six times every November from 2006 to 2011. The study population comprised 168 subjects who underwent all health checkups. SO 2 concentrations were measured at six fixed monitoring stations in inhabitable areas. Based on the annual mean SO 2 concentration, inhabitable areas were classified into three categories; namely, lower (L), higher (H-1), and highest (H-2) areas. Average SO 2 concentrations (ppb) during 3 months prior to each health checkup dropped from 11.3 to 3.29, 32.2 to 13.4 and 75.1 to 12.6 from 2006 to 2010/2011 in L, H-1, and H-2. No significant declines in pulmonary function were observed in all areas. However, prevalence of subjective symptoms such as "Cough," "Irritation and/or pain in throat," "Irritation, runny nose, and/or nasal sniffles," and "Irritation and/or pain in the eyes," dependently increased on SO 2 concentration. Odds ratios were statistically significant at approximately 70 ppb of SO 2 or above. Adult residents of Miyakejima island showed no deterioration in pulmonary function at SO 2 levels, but complained of respiratory/irritative symptoms in an SO 2 concentration-dependent manner.

Dynamics and Fragmentation of Hydrogen Bonded and van der Waal Clusters upon 26.5 eV Soft X-ray Laser Ionization

NASA Astrophysics Data System (ADS)

Dong, Feng; Heinbuch, Scott; Bernstein, Elliot; Rocca, Jorge

2006-05-01

A desk-top soft x-ray laser is applied to the study of water, methanol, ammonia, sulfur dioxide, carbon dioxide, mixed sulfur dioxide-water, and mixed carbon dioxide-water clusters through single photon ionization time of flight mass spectroscopy. Almost all of the energy above the vertical ionization energy is removed by the ejected electron. Protonated water, methanol, and ammonia clusters dominate the mass spectra for the first three systems. The temperatures of the neutral water and methanol clusters can be estimated. In the case of pure SO2 and CO2, the mass spectra are dominated by (SO2)n^+ and (CO2)n^+ cluster series. When a high or low concentration of SO2/CO2 is mixed with water, we observe (SO2/CO2)nH2O^+ or SO2/CO2(H2O)nH^+ in the mass spectra, respectively. The unimolecular dissociation rate constants for reactions involving loss of one neutral molecule are calculated for the protonated water, methanol, and ammonia clusters as well as for SO2 and CO2 clusters. We find that the 26.5 eV soft x-ray laser is a nearly ideal tool for the study of hydrogen bonded and van der Waals cluster systems and we are currently exploring its usefulness for other more strongly bound systems.

Effect of controlled low levels of SO/sub 2/ on grasshopper densities on a northern mixed-grass prairie

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

McNary, T.J.; Milchunas, D.G.; Leetham, J.W.

1981-02-01

A northern mixed-grass prairie was exposed to monthly median SO/sub 2/ concentrations of 73, 134, and 228 ..mu..g/m/sup 3/. Total grasshopper density and the density of Melanoplus sanguinipes (F.) were significantly (P < 0.01) reduced by SO/sub 2/ treatment on late-growing-season dates within each year of SO/sub 2/ exposure. Grasshopper density tended to decrease with increasing SO/sub 2/ concentration. Sulfur dioxide did not alter the relative proportions of M. sanguinipes in the total population. 14 references, 1 figure.

Measuring the impact of global tropospheric ozone, carbon dioxide and sulfur dioxide concentrations on biodiversity loss.

PubMed

Ahmed Bhuiyan, Miraj; Rashid Khan, Haroon Ur; Zaman, Khalid; Hishan, Sanil S

2018-01-01

The aim of this study is to examine the impact of air pollutants, including mono-nitrogen oxides (NOx), nitrous oxide (N 2 O), sulfur dioxide (SO 2 ), carbon dioxide emissions (CO 2 ), and greenhouse gas (GHG) emissions on ecological footprint, habitat area, food supply, and biodiversity in a panel of thirty-four developed and developing countries, over the period of 1995-2014. The results reveal that NOx and SO 2 emissions both have a negative relationship with ecological footprints, while N 2 O emission and real GDP per capita have a direct relationship with ecological footprints. NOx has a positive relationship with forest area, per capita food supply and biological diversity while CO 2 emission and GHG emission have a negative impact on food production. N 2 O has a positive impact on forest area and biodiversity, while SO 2 emissions have a negative relationship with them. SO 2 emission has a direct relationship with per capita food production, while GDP per capita significantly affected per capita food production and food supply variability across countries. The overall results reveal that SO 2 , CO 2 , and GHG emissions affected potential habitat area, while SO 2 and GHG emissions affected the biodiversity index. Trade liberalization policies considerably affected the potential habitat area and biological diversity in a panel of countries. Copyright © 2017 Elsevier Inc. All rights reserved.

Associations between short-term exposure to ambient sulfur dioxide and increased cause-specific mortality in 272 Chinese cities.

PubMed

Wang, Lijun; Liu, Cong; Meng, Xia; Niu, Yue; Lin, Zhijing; Liu, Yunning; Liu, Jiangmei; Qi, Jinlei; You, Jinling; Tse, Lap Ah; Chen, Jianmin; Zhou, Maigeng; Chen, Renjie; Yin, Peng; Kan, Haidong

2018-04-28

Ambient sulfur dioxide (SO 2 ) remains a major air pollutant in developing countries, but epidemiological evidence about its health effects was not abundant and inconsistent. To evaluate the associations between short-term exposure to SO 2 and cause-specific mortality in China. We conducted a nationwide time-series analysis in 272 major Chinese cities (2013-2015). We used the over-dispersed generalized linear model together with the Bayesian hierarchical model to analyze the data. Two-pollutant models were fitted to test the robustness of the associations. We conducted stratification analyses to examine potential effect modifications by age, sex and educational level. On average, the annual-mean SO 2 concentrations was 29.8 μg/m 3 in 272 cities. We observed positive and associations of SO 2 with total and cardiorespiratory mortality. A 10 μg/m 3 increase in two-day average concentrations of SO 2 was associated with increments of 0.59% in mortality from total non-accidental causes, 0.70% from total cardiovascular diseases, 0.55% from total respiratory diseases, 0.64% from hypertension disease, 0.65% from coronary heart disease, 0.58% from stroke, and 0.69% from chronic obstructive pulmonary disease. In two-pollutant models, there were no significant differences between single-pollutant model and two-pollutant model estimates with fine particulate matter, carbon monoxide and ozone, but the estimates decreased substantially after adjusting for nitrogen dioxide, especially in South China. The associations were stronger in warmer cities, in older people and in less-educated subgroups. This nationwide study demonstrated associations of daily SO 2 concentrations with increased total and cardiorespiratory mortality, but the associations might not be independent from NO 2 . Copyright © 2018 Elsevier Ltd. All rights reserved.

REGIONAL TRENDS IN RURAL SULFUR DIOXIDE CONCENTRATIONS OVER THE EASTERN U.S.

EPA Science Inventory

Emission reductions were mandated in the Clean Air Art Amendments of 1990 with the expectation that they would result in corresponding reductions in air pollution. The 1990 amendments include new requirements that appreciably reduced sulfur dioxide (SO2) emissions in two phases o...

Removal of NO from flue gas by aqueous chlorine-dioxide scrubbing solution in a lab-scale bubbling reactor.

PubMed

Deshwal, Bal Raj; Jin, Dong Seop; Lee, Si Hyun; Moon, Seung Hyun; Jung, Jong Hyeon; Lee, Hyung Keun

2008-02-11

The present study attempts to clean up nitric oxide from the simulated flue gas using aqueous chlorine-dioxide solution in the bubbling reactor. Chlorine-dioxide is generated by chloride-chlorate process. Experiments are carried out to examine the effect of various operating variables like input NO concentration, presence of SO(2), pH of the solution and NaCl feeding rate on the NO(x) removal efficiency at 45 degrees C. Complete oxidation of nitric oxide into nitrogen dioxide occurred on passing sufficient ClO(2) gas into the scrubbing solution. NO is finally converted into nitrate and ClO(2) is reduced into chloride ions. A plausible reaction mechanism concerning NO(x) removal by ClO(2) is suggested. DeNO(x) efficiency increased slightly with the increasing input NO concentration. The presence of SO(2) improved the NO(2) absorption but pH of solution showed marginal effect on NO(2) absorption. NO(x) removal mechanism changed when medium of solution changed from acidic to alkaline. A constant NO(x) removal efficiency of about 60% has been achieved in the wide pH range of 3-11 under optimized conditions.

Citizen science identifies the effects of nitrogen dioxide and other environmental drivers on tar spot of sycamore.

PubMed

Gosling, Laura; Ashmore, Mike; Sparks, Tim; Bell, Nigel

2016-07-01

Elevated sulphur dioxide (SO2) concentrations were the major cause of the absence of symptoms of tar spot (Rhytisma acerinum) of sycamore (Acer pseudoplatanus), in urban areas in the 1970s. The subsequent large decline in SO2 concentrations has not always been accompanied by increased tar spot symptoms, for reasons that have remained unresolved. We used a large citizen science survey, providing over 1000 records across England, to test two competing hypotheses proposed in earlier studies. We were able to demonstrate the validity of both hypotheses; tar spot symptoms were reduced where there were fewer fallen leaves as a source of inoculum, and elevated nitrogen dioxide concentrations reduced tar spot symptoms above a threshold concentration of about 20 μg m(-3). Symptom severity was also lower at sites with higher temperature and lower rainfall. Our findings demonstrate the power of citizen science to resolve competing hypotheses about the impacts of air pollution and other environmental drivers. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.

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

EPA Science Inventory

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

Ozone and sulfur dioxide effects on tall fescue. II. Alteration of quality constituents. [Festuca arundinacea

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

Flagler, R.B.; Youngner, V.B.

A greenhouse study was conducted to determine whether ozone (O/sub 3/) and sulfur dioxide (SO/sub 2/) might alter forage quality parameters of tall fescue (Festuca arundinacea Schreb. Alta). Plants were exposed weekly to four O/sub 3/ treatments, 0, 0.10, 0.20, and 0.30 ..mu..L L/sup -1/; with or without 0.10 ..mu..L L/sup -1/ SO/sub 2/, 6 h d/sup -1/ for 12 weeks. Ozone had a much greater impact on forage quality than did SO/sub 2/. Ozone increased protein content on a g kg/sup -1/ basis and decreased protein on a weight per plant basis. Ozone reduced crude fat, crude fiber, andmore » total nonstructural carbohydrate contents of the forage. Crude ash content increased due to O/sub 3/ exposure. On a weight per plant basis, O/sub 3/ decreased the forage concentration of Ca, Mg, and P. Ozone increased Ca concentration of herbage. Sulfur dioxide increased ash content of the forage. Phosphorus concentration and weight per plant of Mg and P were all reduced by SO/sub 2/ Significant pollutant interactions occurred for crude fiber, crude ash, total Mg, and total P contents of forage. While treatments resulted in some apparent increases in forage quality, these were at the expense of yield. The most adverse effects on forage quality were an increase in ash content which resulted from an interaction of SO/sub 2/ with O/sub 3/, and a reduction in soluble carbohydrate content of shoots due to O/sub 3/.« less

Impact of cruise ship emissions in Victoria, BC, Canada

NASA Astrophysics Data System (ADS)

Poplawski, Karla; Setton, Eleanor; McEwen, Bryan; Hrebenyk, Dan; Graham, Mark; Keller, Peter

2011-02-01

Characterization of the effects of cruise ship emissions on local air quality is scarce. Our objective was to investigate community level concentrations of fine particulate matter (PM 2.5), nitrogen dioxide (NO 2) and sulphur dioxide (SO 2) associated with cruise ships in James Bay, Victoria, British Columbia (BC), Canada. Data obtained over four years (2005-2008) at the nearest air quality network site located 3.5 km from the study area, a CALPUFF modeling exercise (2007), and continuous measurements taken in the James Bay community over a three-month period during the 2009 cruise ship season were examined. Concentrations of PM 2.5 and nitrogen oxide (NO) were elevated on weekends with ships present with winds from the direction of the terminal to the monitoring station. SO 2 displayed the greatest impact from the presence of cruise ships in the area. Network data showed peaks in hourly SO 2 when ships were in port during all years. The CALPUFF modeling analysis found predicted 24-hour SO 2 levels to exceed World Health Organization (WHO) guidelines of 20 μg m -3 for approximately 3% of 24-hour periods, with a maximum 24-hour concentration in the community of 41 μg m -3; however, the CALPUFF model underestimated concentrations when predicted and measured concentrations were compared at the network site. Continuous monitoring at the location in the community predicted to experience highest SO 2 concentrations measured a maximum 24-hour concentration of 122 μg m -3 and 16% of 24-hour periods were above the WHO standard. The 10-minute concentrations of SO 2 reached up to 599 μg m -3 and exceeded the WHO 10-minute SO 2 guideline (500 μg m -3) for 0.03% of 10-minute periods. No exceedences of BC Provincial or Canadian guidelines or standards were observed.

Analysis of Nitrogen Dioxide and Sulphur Dioxide in Lima, Peru: Trends and Seasonal Variations

NASA Astrophysics Data System (ADS)

Pacsi, S.; Rappenglueck, B.

2007-12-01

This research was carried out to show a general analysis of the monthly and yearly variation (1996-2002) and the tendency of the nitrogen dioxide (NO2) and sulfur dioxide (SO2) for the 5 stations of the air quality network of Lima. The SO2 and NO2 concentrations were measured by the Dirección General de Salud Ambiental (DIGESA), using the active sampling method and the chemical analysis has been determined by Turbidimetry and Colorimetry for the SO2 and NO2 respectively. The monthly average variation (1996-2001) of SO2 in the Lima Center station has a small annual range (32,4 mikrograms/m3) with maximum values in autumn (April) and minimum in winter (June). The NO2 presents a higher annual range (128,2 mikrograms/m3) and its minimum values occur in the summer and the maximum in spring. The annual averages analysis (2000-2002) of the air quality monitoring network of Lima shows that the SO2 and NO2 values are maximum in the Lima Center station and exceed the Peruvian air quality standard (ECAs) in 30% and 75% respectively. The yearly variation (1996-2001) in the Lima Center station show an increasing tendency in the SO2 (significant) and NO2 (not significant) values, which indicates the critical level of the air quality in Lima, therefore the implementation of the air pollution control programs is urgent.

40 CFR Table B-3 to Subpart B of... - Interferent Test Concentration, 1 Parts per Million

Code of Federal Regulations, 2013 CFR

2013-07-01

... Nitric oxide Carbon dioxide Ethylene Ozone Mxy-lene Water vapor Carbon monoxide Methane Ethane... 4 0.14 750 3 20,000 50 SO2 Gas chromatography 0.1 4 0.14 750 3 20,000 50 SO2 Spectrophotometric-wet... 0.5 3 20,000 SO2 Conductivity 0.2 0.1 4 0.14 0.5 750 SO2 Spectrophotometric-gas phase, including...

Chronic obstructive pulmonary diseases related to outdoor PM10, O3, SO2, and NO2 in a heavily polluted megacity of Iran.

PubMed

Khaniabadi, Yusef Omidi; Daryanoosh, Mohammad; Sicard, Pierre; Takdastan, Afshin; Hopke, Philip K; Esmaeili, Shirin; De Marco, Alessandra; Rashidi, Rajab

2018-04-18

This study was conducted to quantify, by an approach proposed by the World Health Organization (WHO), the daily hospital admissions for chronic obstructive pulmonary disease (COPD) related to exposure to particulate matter (PM 10 ) and oxidants such as ozone (O 3 ), sulfur dioxide (SO 2 ), and nitrogen dioxide (NO 2 ) in a heavily polluted city in Iran. For the health impact assessment, in terms of COPD, the current published relative risk (RR) and baseline incidence (BI) values, suggested by the WHO, and the 1-h O 3 concentrations and daily PM 10 , NO 2 , and SO 2 concentrations were compiled. The results showed that 5.9, 4.1, 1.2, and 1.9% of the COPD daily hospitalizations in 2011 and 6.6, 1.9, 2.3, and 2.1% in 2012 were attributed to PM 10 , O 3 , SO 2 , and NO 2 concentrations exceeding 10 μg/m 3 , respectively. This study indicates that air quality and the high air pollutant levels have an effect on COPD morbidity. Air pollution is associated with visits to emergency services and hospital admissions. A lower relative risk can be achieved if some stringent control strategies for reducing air pollutants or emission precursors are implemented.

The State of Ambient Air Quality in Two Ugandan Cities: A Pilot Cross-Sectional Spatial Assessment.

PubMed

Kirenga, Bruce J; Meng, Qingyu; van Gemert, Frederik; Aanyu-Tukamuhebwa, Hellen; Chavannes, Niels; Katamba, Achilles; Obai, Gerald; van der Molen, Thys; Schwander, Stephan; Mohsenin, Vahid

2015-07-15

Air pollution is one of the leading global public health risks but its magnitude in many developing countries' cities is not known. We aimed to measure the concentration of particulate matter with aerodynamic diameter <2.5 µm (PM2.5), nitrogen dioxide (NO2), sulfur dioxide (SO2), and ozone (O3) pollutants in two Ugandan cities (Kampala and Jinja). PM2.5, O3, temperature and humidity were measured with real-time monitors, while NO2 and SO2 were measured with diffusion tubes. We found that the mean concentrations of the air pollutants PM2.5, NO2, SO2 and O3 were 132.1 μg/m3, 24.9 µg/m3, 3.7 µg/m3 and 11.4 μg/m3, respectively. The mean PM2.5 concentration is 5.3 times the World Health Organization (WHO) cut-off limits while the NO2, SO2 and O3 concentrations are below WHO cut-off limits. PM2.5 levels were higher in Kampala than in Jinja (138.6 μg/m3 vs. 99.3 μg/m3) and at industrial than residential sites (152.6 μg/m3 vs. 120.5 μg/m3) but residential sites with unpaved roads also had high PM2.5 concentrations (152.6 μg/m3). In conclusion, air pollutant concentrations in Kampala and Jinja in Uganda are dangerously high. Long-term studies are needed to characterize air pollution levels during all seasons, to assess related public health impacts, and explore mitigation approaches.

Performances and application of a passive sampling method for the simultaneous determination of nitrogen dioxide and sulfur dioxide in ambient air.

PubMed

Plaisance, H; Sagnier, I; Saison, J Y; Galloo, J C; Guillermo, R

2002-11-01

The performances and applicability of a diffusion tube sampler for the simultaneous measurements of NO2 and SO2 in ambient air were evaluated. SO2 and NO2 are collected by the passive sampler using triethanolamine as trapping agent and are determined as sulphate and nitrite with ion chromatography. The detection limit (2.3 microg m(-3) of NO2 and 4.2 microg m(-3) of SO2 for two weeks sampling) is adequate for the determination of concentrations in urban and industrial areas. Precision of the method as RSD is in mean 5% for NO2 and 12% for SO2 at the concentration levels in urban areas. Calibration of the method was performed in the field conditions by comparison between the responses of sampler and the concentrations measured by the continuous monitors. High degree of linearity (correlation coefficients > 0.8) is found between the passive sampler tube and the continuous monitor data for both NO2 and SO2. To reduce the wind velocity influence on passive sampling of diffusion tubes, a protective shelter was tested in this study. The overall uncertainty of one measure for the optimised method is estimated at 5 microg m(-3) for NO2 and 6 microg m(-3) for SO2. Suitability of this passive sampling method for air pollution monitoring in urban areas was demonstrated by the results shown in this paper on a campaign carried out in the French agglomeration.

Short-term association between sulfur dioxide and daily mortality: the Public Health and Air Pollution in Asia (PAPA) study.

PubMed

Kan, Haidong; Wong, Chit-Ming; Vichit-Vadakan, Nuntavarn; Qian, Zhengmin

2010-04-01

Sulfur dioxide (SO(2)) has been associated with increased mortality and morbidity, but only few studies were conducted in Asian countries. Previous studies suggest that SO(2) may have adverse health effects independent of other pollutants. In the Public Health and Air Pollution in Asia (PAPA) project, the short-term associations between ambient sulfur dioxide (SO(2)) and daily mortality were examined in Bangkok, Thailand, and three Chinese cities: Hong Kong, Shanghai, and Wuhan. Poisson regression models incorporating natural spline smoothing functions were used to adjust for seasonality and other time-varying covariates. Effect estimates were obtained for each city and then for the cities combined. The impact of alternative model specifications, such as lag structure of pollutants and degree of freedom (df) for time trend, on the estimated effects of SO(2) were also examined. In both individual-city and combined analysis, significant effects of SO(2) on total non-accidental and cardiopulmonary mortality were observed. An increase of 10 microg/m(3) of 2-day moving average concentrations of SO(2) corresponded to 1.00% [95% confidence interval (CI), 0.75-1.24], 1.09% (95% CI, 0.71-1.47), and 1.47% (95% CI, 0.85-2.08) increase of total, cardiovascular and respiratory mortality, respectively, in the combined analysis. Sensitivity analyzes suggested that these findings were generally insensitive to alternative model specifications. After adjustment for PM(10) or O(3), the effect of SO(2) remained significant in three Chinese cities. However, adjustment for NO(2) diminished the associations and rendered them statistically insignificant in all four cities. In conclusion, ambient SO(2) concentration was associated with daily mortality in these four Asian cities. These associations may be attributable to SO(2) serving as a surrogate of other substances. Our findings suggest that the role of outdoor exposure to SO(2) should be investigated further in this region. (c) 2010 Elsevier Inc. All rights reserved.

Estimating Sulfur Dioxide in Volcanic Plumes Using an Ultraviolet Camera. First Results from Lascar, Ollagüe and Irruputuncu Volcanoes

NASA Astrophysics Data System (ADS)

Geoffroy, C. A.; Amigo, A.

2014-12-01

Volcanic gas fluxes give important information on both the amount of degassing and magma reservoirs. In most of magmas, water vapor (H2O) and carbon dioxide (CO2) are major components of volcanic gas. However, sulfur dioxide (SO2) is one of the targets of remote sensing due to their low concentration in the environment and easy detection by ultraviolet spectroscopy. Accordingly, plume imaging using passive ultraviolet cameras is a relatively simple method to study volcanic degassing, expeditious manner and can be used up from distances of about 10 km from source of emissions. We estimated SO2 concentrations and fluxes in volcanic plumes with the ultraviolet camera Envicam-2, developed by Nicarnica Aviation, acquired by the Geological Survey of Chile (SERNAGEOMIN). The camera has filters that allow passage of ultraviolet radiation at wavelengths of interest. For determining whether there is absorption of radiation associated with the presence of SO2 the Beer-Lambert law was used for quantifying concentrations using appropriate calibration cells. SO2 emissions to the atmosphere were estimated using wind speed as an approximation to the plume transport. In this study we reported the implementation of a new methodology for using Envicam-2 and subsequent collection of SO2 concentrations and fluxes in passive degassing volcanoes. Measurements were done at Lascar, Ollagüe and Irruputuncu volcanoes, located in northern Chile. The volcanoes were chosen because of optimal atmospheric conditions for ultraviolet imaging. Results indicate concentrations within the expected ranges for three volcanoes generally between 400-1700 ppm•m. In the case of Láscar volcano, the emission rates of SO2 range from 250 to 500 tonnes/day for a same image of the plume. In particular, wind speed was determined from scaling images and are consistent with data from regional numerical models, as well as records of the meteorological stations installed at the ALMA astronomical center, located about 40 km north of the volcano. This study reveals new insights and challenges related to remote sensing of volcanic gases in Chile. In particular, the evolution of the SO2 emission in active volcanoes can be a powerful monitoring tool that can be complemented with other geophysical techniques.

Ambient air sulphur dioxide and sulphate accumulation in deciduous and evergreen plants.

PubMed

Dwivedi, Anil K; Shashi

2012-01-01

Present study is an attempt to evaluate the difference in rate of sulphur dioxide (SO2) absorption by deciduous (Ficus religiosa) and evergreen (Carica papaya) plants, under elevated concentration of the gas in ambient air. Two-way ANOVA for SO2 in air and sulphate (SO4) accumulation in both the selected plants showed significant difference (p<0.01) at different study sites; different months as well as interaction effect of both site and months. The linear correlation coefficient among ambient air SO2 and SO4 in leaves was always significant (p<0.001) in case of deciduous plant; however, the same in evergreen plants showed heterogeneous result. Air pollution tolerance index (APTI) of F. religiosa (deciduous) and C. papaya (evergreen) was found to be 19.73 and 81.10 respectively, proving that the former has low tolerance capacity and is sensitive, while the latter is resistant to the elevated ambient air SO2.

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

USGS Publications Warehouse

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

1997-01-01

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

Environmental sulfur dioxide: toxicity toward the alveolar macrophage

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

Butenhoff, J.L.

This study was designed to determine if SO/sub 2/ and/or its associated ions in solution (H/sub 3/O/sup +/, HSO/sub 3//sup -/, SO/sub 3//sup =/ and SO/sub 4//sup =/) are cytotoxic to rat PAM cells in primary culture. The indices of cytotoxicity which were evaluated included cell viability uptake of particles and viable bacteria, inhibition of antioxidant enzymes, cell surface morphology and oxygen utilization. For determining effects on cell viability, function and morphology, exposures were conducted for 20 hours at either 30 or 37 deg. C in Leighton culture tubes of polystyrene petri dishes. In both instances, cells were attached tomore » glass. Cell viability dose-response curves were obtained with H/sub 3/O/sup +/ (HCl and H/sub 2/SO/sub 4/), SO/sub 2/ (dissolved gas), HSO/sub 3//sup -/, SO/sub 3//sup =/ and SO/sub 4//sup =/. Buffer strength and pH were varied to determine the effect of these various molecular species on viability. Sulfur dioxide gas exhibited a weak protentiating effect on H/sub 3/O/sup +/ toxicity below pH 6.4. Significant viability loss did not occur above pH 6.4. Particle uptake was diminished significantly at sulfite concentration greater than or equal to 500 uM, pH 7.2. Sulfite was found to be a potent competitive inhibitor of GSH-peroxidase in vitro. A slight yet significant change in cell morphology occurred at sulfite concentrations of 200 uM and 4000 uM and pH 7.2. There was a significant difference in O/sub 2/ utilization between control and 4000 uM exposed cells, indicating a potential diminution in cell-surface mediated respiratory stimulation. Based on these studies, sulfur dioxide gas exposure may have an effect on alveolar macrophage function depending on the ambient concentration of the gas and its accumulation in the airspaces of the lung.« less

Monitoring ambient sulfur dioxide levels at some residential environments in the Greater Cairo urban Region--Egypt.

PubMed

El-Dars, F M S; Mohamed, A M F; Aly, H A T

2004-07-01

The impact of the increased sulfur dioxide emissions within the Greater Cairo Urban Region over the part 50 yr has been overwhelming. While previous air-pollution surveys measuring SO2 levels in the region converged upon the study of emissions from specific industrial activities, no correlation between the measured concentrations and the induced health-related impacts in living environments was provided. As well, no inventory of emissions from other sources within some residential areas were accounted for or evaluated. During the study period of January to April 2000, the ambient sulfur dioxide levels in four residential locations within the capital region were investigated. The results indicated that the measured cumulative ambient SO2 concentrations were in excess of the national and the international monthly mean exposure limits, irrespective of the type of local activity. As well, measurements within three of the selected environments surpassed the 0.5 ppm SO2 odor-threshold. The data also showed a significant dependency of the measured content upon the physical layout and topography of the studied environment as well as with respect to the prevailing seasonal weather conditions.

Thermo Scientific Sulfur Dioxide Analyzer Instrument Handbook

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

Springston, S. R.

The Sulfur Dioxide Analyzer measures sulfur dioxide based on absorbance of UV light at one wavelength by SO2 molecules which then decay to a lower energy state by emitting UV light at a longer wavelength. Specifically, SO2 + hυ1 →SO2 *→SO2 + hυ2 The emitted light is proportional to the concentration of SO2 in the optical cell. External communication with the analyzer is available through an Ethernet port configured through the instrument network of the AOS systems. The Model 43i-TLE is part of the i-series of Thermo Scientific instruments. The i-series instruments are designed to interface with external computers throughmore » the proprietary Thermo Scientific iPort Software. However, this software is somewhat cumbersome and inflexible. BNL has written an interface program in National Instruments LabView that both controls the Model 43i-TLE Analyzer AND queries the unit for all measurement and housekeeping data. The LabView vi (the software program written by BNL) ingests all raw data from the instrument and outputs raw data files in a uniform data format similar to other instruments in the AOS and described more fully in Section 6.0 below.« less

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

PubMed Central

Hu, Guoxin

2013-01-01

This study shows the ability of sodium humate from alkaline treatment sludge on removing sulfur dioxide (SO2) in the simulated flue gas. Experiments were conducted to examine the effect of various operating parameters, like the inlet SO2 concentration or temperature or O2, on the SO2 absorption efficiency and desulfurization time in a lab-scale bubbling reactor. The sludge sodium humate in the supernatant after alkaline sludge treatment shows great performance in SO2 absorption, and such efficiency can be maintained above 98% with 100 mL of this absorption solution at 298 K (flue gas rate of 0.12 m3/h). The highest SO2 absorption by 1.63 g SHA-Na is 0.946 mmol in the process, which is translated to 0.037 g SO2 g−1 SHA-Na. The experimental results indicate that the inlet SO2 concentration slightly influences the SO2 absorption efficiency and significantly influences the desulfurization time. The pH of the absorption solution should be above 3.5 in this process in order to make an effective desulfurization. The products of this process were characterized by Fourier transform infrared spectroscopy and X-ray diffraction. It can be seen that the desulfurization products mainly contain sludge humic acid sediment, which can be used as fertilizer components. PMID:24453875

[Effects of carbon dioxide insufflation on regional cerebral oxygenation during laparoscopic surgery in children: a prospective study].

PubMed

Tuna, Ayca Tas; Akkoyun, Ibrahim; Darcin, Sevtap; Palabiyik, Onur

2016-01-01

Laparoscopic surgery has become a popular surgical tool when compared to traditional open surgery. There are limited data on pediatric patients regarding whether pneumoperitoneum affects cerebral oxygenation although end-tidal CO2 concentration remains normal. Therefore, this study was designed to evaluate the changes of cerebral oxygen saturation using near-infrared spectroscope during laparoscopic surgery in children. The study comprised forty children who were scheduled for laparoscopic (Group L, n=20) or open (Group O, n=20) appendectomy. Hemodynamic variables, right and left regional cerebral oxygen saturation (RrSO2 and LrSO2), fraction of inspired oxygen, end-tidal carbon dioxide pressure (PETCO2), peak inspiratory pressure (Ppeak), respiratory minute volume, inspiratory and end-tidal concentrations of sevoflurane and body temperature were recorded. All parameters were recorded after anesthesia induction and before start of surgery (T0, baseline), 15min after start of surgery (T1), 30min after start of surgery (T2), 45min after start of surgery (T3), 60min after start of surgery (T4) and end of the surgery (T5). There were progressive decreases in both RrSO2 and LrSO2 levels in both groups, which were not statistically significant at T1, T2, T3, T4. The RrSO2 levels of Group L at T5 were significantly lower than that of Group O. One patient in Group L had an rSO2 value <80% of the baseline value. Carbon dioxide insufflation during pneumoperitoneum in pediatric patients may not affect cerebral oxygenation under laparoscopic surgery. Copyright © 2015 Sociedade Brasileira de Anestesiologia. Publicado por Elsevier Editora Ltda. All rights reserved.

Effects of carbon dioxide insufflation on regional cerebral oxygenation during laparoscopic surgery in children: a prospective study.

PubMed

Tuna, Ayca Tas; Akkoyun, Ibrahim; Darcin, Sevtap; Palabiyik, Onur

2016-01-01

Laparoscopic surgery has become a popular surgical tool when compared to traditional open surgery. There are limited data on pediatric patients regarding whether pneumoperitoneum affects cerebral oxygenation although end-tidal CO2 concentration remains normal. Therefore, this study was designed to evaluate the changes of cerebral oxygen saturation using near-infrared spectroscope during laparoscopic surgery in children. The study comprised forty children who were scheduled for laparoscopic (Group L, n=20) or open (Group O, n=20) appendectomy. Hemodynamic variables, right and left regional cerebral oxygen saturation (RrSO2 and LrSO2), fraction of inspired oxygen, end-tidal carbon dioxide pressure (PETCO2), peak inspiratory pressure (Ppeak), respiratory minute volume, inspiratory and end-tidal concentrations of sevoflurane and body temperature were recorded. All parameters were recorded after anesthesia induction and before start of surgery (T0, baseline), 15min after start of surgery (T1), 30min after start of surgery (T2), 45min after start of surgery (T3), 60min after start of surgery (T4) and end of the surgery (T5). There were progressive decreases in both RrSO2 and LrSO2 levels in both groups, which were not statistically significant at T1, T2, T3, T4. The RrSO2 levels of Group L at T5 were significantly lower than that of Group O. One patient in Group L had an rSO2 value <80% of the baseline value. Carbon dioxide insufflation during pneumoperitoneum in pediatric patients may not affect cerebral oxygenation under laparoscopic surgery. Copyright © 2015 Sociedade Brasileira de Anestesiologia. Published by Elsevier Editora Ltda. All rights reserved.

Effect of concentration, exposure time, temperature, and relative humidity on the toxicity of sulfur dioxide to the spores of Botrytis cinerea

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

Couey, H.M.; Uota, M.

1961-12-01

When spores of Botrytis cinerea are exposed to SO/sub 2/ gas, the subsequent reduction in spore germination is quantitatively proportional to the SO/sub 2/ concentration and the exposure time. The toxicity of SO/sub 2/ increases with increasing relative humidity. In an atmosphere of 96% RH, SO/sub 2/ is more than 20 times as effective as at 75% RH. The toxicity also increases about 1.5 times for each 10/sup 0/C rise in temperature between 0/sup 0/ and 30/sup 0/C. 8 references, 4 figures, 1 table.

Selective methods for polyphenols and sulphur dioxide determination in wines.

PubMed

García-Guzmán, Juan J; Hernández-Artiga, María P; Palacios-Ponce de León, Lourdes; Bellido-Milla, Dolores

2015-09-01

A critical review to the methods recommended by international bodies and widely used in the winery industry and research studies was performed. A Laccase biosensor was applied to the selective determination of polyphenols in wines. The biosensor response was characterised and it responds mainly to o-diphenols which are the principal polyphenols responsible for the stability and sensory qualities of wines. The spectrophotometric method to determine free and total sulphur dioxide recommended for beers was applied directly to wines. A sampling of 14 red and white wines was performed and they were analysed for biosensor polyphenol index (IBP) and sulphur dioxide concentration (SO2). The antioxidant capacity by the ABTS(+) spectrophotometric method was also determined. A correlation study was performed to elucidate the influence of the polyphenols and SO2 on the wines stability. High correlations were found between IBP and antioxidant capacity and low correlation between SO2 and antioxidant capacity. To evaluate the benefits of wine drinking a new parameter (IBP/SO2) is proposed. Copyright © 2015 Elsevier Ltd. All rights reserved.

The State of Ambient Air Quality in Two Ugandan Cities: A Pilot Cross-Sectional Spatial Assessment

PubMed Central

Kirenga, Bruce J.; Meng, Qingyu; van Gemert, Frederik; Aanyu-Tukamuhebwa, Hellen; Chavannes, Niels; Katamba, Achilles; Obai, Gerald; van der Molen, Thys; Schwander, Stephan; Mohsenin, Vahid

2015-01-01

Air pollution is one of the leading global public health risks but its magnitude in many developing countries’ cities is not known. We aimed to measure the concentration of particulate matter with aerodynamic diameter <2.5 µm (PM2.5), nitrogen dioxide (NO2), sulfur dioxide (SO2), and ozone (O3) pollutants in two Ugandan cities (Kampala and Jinja). PM2.5, O3, temperature and humidity were measured with real-time monitors, while NO2 and SO2 were measured with diffusion tubes. We found that the mean concentrations of the air pollutants PM2.5, NO2, SO2 and O3 were 132.1 μg/m3, 24.9 µg/m3, 3.7 µg/m3 and 11.4 μg/m3, respectively. The mean PM2.5 concentration is 5.3 times the World Health Organization (WHO) cut-off limits while the NO2, SO2 and O3 concentrations are below WHO cut-off limits. PM2.5 levels were higher in Kampala than in Jinja (138.6 μg/m3 vs. 99.3 μg/m3) and at industrial than residential sites (152.6 μg/m3 vs. 120.5 μg/m3) but residential sites with unpaved roads also had high PM2.5 concentrations (152.6 μg/m3). In conclusion, air pollutant concentrations in Kampala and Jinja in Uganda are dangerously high. Long-term studies are needed to characterize air pollution levels during all seasons, to assess related public health impacts, and explore mitigation approaches. PMID:26184273

Impact of Diwali celebrations on urban air and noise quality in Delhi City, India.

PubMed

Mandal, Papiya; Prakash, Mamta; Bassin, J K

2012-01-01

A study was conducted in the residential areas of Delhi, India, to assess the variation in ambient air quality and ambient noise levels during pre-Diwali month (DM), Diwali day (DD) and post-Diwali month during the period 2006 to 2008. The use of fireworks during DD showed 1.3 to 4.0 times increase in concentration of respirable particulate matter (PM(10)) and 1.6 to 2.5 times increase in concentration of total suspended particulate matter (TSP) than the concentration during DM. There was a significant increase in sulfur dioxide (SO(2)) concentration but the concentration of nitrogen dioxide (NO(2)) did not show any considerable variation. Ambient noise level were 1.2 to 1.3 times higher than normal day. The study also showed a strong correlation between PM(10) and TSP (R (2) ≥ 0.9) and SO(2) and NO(2) (R (2) ≥ 0.9) on DD. The correlation between noise level and gaseous pollutant were moderate (R (2) ≥ 0.5). The average concentration of the pollutants during DD was found higher in 2007 which could be due to adverse meteorological conditions. The statistical interpretation of data indicated that the celebration of Diwali festival affects the ambient air and noise quality. The study would provide public awareness about the health risks associated with the celebrations of Diwali festival so as to take proper precautions.

EVALUATION OF ALTERNATIVE GAUSSIAN PLUME DISPERSION MODELING TECHNIQUES IN ESTIMATING SHORT-TERM SULFUR DIOXIDE CONCENTRATIONS

EPA Science Inventory

A routinely applied atmospheric dispersion model was modified to evaluate alternative modeling techniques which allowed for more detailed source data, onsite meteorological data, and several dispersion methodologies. These were evaluated with hourly SO2 concentrations measured at...

Io - Longtudinal distribution of sulfur dioxide frost

NASA Technical Reports Server (NTRS)

Nelson, R. M.; Lane, A. L.; Matson, D. L.; Fanale, F. P.; Nash, D. B.; Johnson, T. V.

1980-01-01

A longitudinal variation in the distribution of SO2 frost on Io is examined. Twenty spectra of Io (0.26 to 0.33 micrometer) are presented and a strong ultraviolet absorption is found shortward of 0.33 micrometer. The abundance of frost is greatest at orbital longitudes 72 to 137 degrees. Longitudes 250 to 323 degrees are least abundant in SO2. Comparisons are made with a Voyager color relief map, which suggest that SO2 frost is in greatest concentration in the white areas of Io and other sulfurous materials are in greatest concentration in the red areas.

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

Code of Federal Regulations, 2014 CFR

2014-07-01

... into the atmosphere from any affected facility which combusts solid solvent refined coal (SRC-I) any... (1.2 lb/MWh) net energy output; or (iii) 3 percent of the potential combustion concentration (97...

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

Code of Federal Regulations, 2013 CFR

2013-07-01

... into the atmosphere from any affected facility which combusts solid solvent refined coal (SRC-I) any... (1.2 lb/MWh) net energy output; or (iii) 3 percent of the potential combustion concentration (97...

Chemical kinetics of homogeneous atmospheric oxidation of sulfur dioxide

NASA Technical Reports Server (NTRS)

Sander, S. P.; Seinfeld, J. H.

1976-01-01

A systematic evaluation of known homogeneous SO2 reactions which might be important in air pollution chemistry is carried out. A mechanism is developed to represent the chemistry of NOx/hydrocarbon/SO2 systems, and the mechanism is used to analyze available experimental data appropriate for quantitative analysis of SO2 oxidation kinetics. Detailed comparisons of observed and predicted concentration behavior are presented. In all cases, observed SO2 oxidation rates cannot be explained solely on the basis of those SO2 reactions for which rate constants have been measured. The role of ozone-olefin reactions in SO2 oxidation is elucidated.

Summer-time distribution of air pollutants in Sequoia National Park, California.

PubMed

Bytnerowicz, Andrzej; Tausz, Michael; Alonso, Rocio; Jones, David; Johnson, Ronald; Grulke, Nancy

2002-01-01

Concentrations of air pollutants were monitored during the May November 1999 period on a network of forested sites in Sequoia National Park, California. Measurements were conducted with: (1) active monitors for nitric oxide (NO), nitrogen dioxide (NO2) and ozone (O3); (2) honeycomb denuder/filter pack systems for nitric acid vapor (HNO3), nitrous acid vapor (HNO2), ammonia (NH3), sulfur dioxide (SO2), particulate nitrate (NO3-), ammonium (NH4+), and sulfate (SO4(2-)); and (3) passive samplers for O3, HNO3 and NO2. Elevated concentrations of O3 (seasonal means 41-71 ppb), HNO3 (seasonal means 0.4-2.9 microg/m3), NH3 (seasonal means 1.6-4.5 microg/m3), NO3 (1.1-2.0 microg/m3) and NH4+ (1.0-1.9 microg/m3) were determined. Concentrations of other pollutants were low. With increasing elevation and distance from the pollution source area of O3, NH3 and HNO3 concentrations decreased. Ammonia and NH4+ were dominant N pollutants indicating strong influence of agricultural emissions on forests and other ecosystems of the Sequoia National Park.

Meteorological influence on predicting surface SO2 concentration from satellite remote sensing in Shanghai, China.

PubMed

Xue, Dan; Yin, Jingyuan

2014-05-01

In this study, we explored the potential applications of the Ozone Monitoring Instrument (OMI) satellite sensor in air pollution research. The OMI planetary boundary layer sulfur dioxide (SO2_PBL) column density and daily average surface SO2 concentration of Shanghai from 2004 to 2012 were analyzed. After several consecutive years of increase, the surface SO2 concentration finally declined in 2007. It was higher in winter than in other seasons. The coefficient between daily average surface SO2 concentration and SO2_PBL was only 0.316. But SO2_PBL was found to be a highly significant predictor of the surface SO2 concentration using the simple regression model. Five meteorological factors were considered in this study, among them, temperature, dew point, relative humidity, and wind speed were negatively correlated with surface SO2 concentration, while pressure was positively correlated. Furthermore, it was found that dew point was a more effective predictor than temperature. When these meteorological factors were used in multiple regression, the determination coefficient reached 0.379. The relationship of the surface SO2 concentration and meteorological factors was seasonally dependent. In summer and autumn, the regression model performed better than in spring and winter. The surface SO2 concentration predicting method proposed in this study can be easily adapted for other regions, especially most useful for those having no operational air pollution forecasting services or having sparse ground monitoring networks.

Multicontaminant air pollution in Chinese cities

PubMed Central

Han, Lijian; Zhou, Weiqi; Pickett, Steward TA; Li, Weifeng; Qian, Yuguo

2018-01-01

Abstract Objective To investigate multicontaminant air pollution in Chinese cities, to quantify the urban population affected and to explore the relationship between air pollution and urban population size. Methods We obtained data for 155 cities with 276 million inhabitants for 2014 from China's air quality monitoring network on concentrations of fine particulate matter measuring under 2.5 μm (PM2.5), coarse particulate matter measuring 2.5 to 10 μm (PM10), nitrogen dioxide (NO2), sulfur dioxide (SO2) and ozone (O3). Concentrations were considered as high, if they exceeded World Health Organization (WHO) guideline limits. Findings Overall, 51% (142 million) of the study population was exposed to mean annual multicontaminant concentrations above WHO limits – east China and the megacities were worst affected. High daily levels of four-contaminant mixtures of PM2.5, PM10, SO2 and O3 and PM2.5, PM10, SO2 and NO2 occurred on up to 110 days in 2014 in many cities, mainly in Shandong and Hebei Provinces. High daily levels of PM2.5, PM10 and SO2 occurred on over  146 days in 110 cities, mainly in east and central China. High daily levels of mixtures of PM2.5 and PM10, PM2.5 and SO2, and PM10 and SO2 occurred on over  146 days in 145 cities, mainly in east China. Surprisingly, multicontaminant air pollution was less frequent in cities with populations over 10 million than in smaller cities. Conclusion Multicontaminant air pollution was common in Chinese cities. A shift from single-contaminant to multicontaminant evaluations of the health effects of air pollution is needed. China should implement protective measures during future urbanization. PMID:29695880

[Evaluation of different oxygen therapies on therapeutic effects in rats with acute carbon dioxide poisoning].

PubMed

Niu, Ying-mei; Hao, Feng-tong; Xue, Chang-jiang; Xia, Yu-jing; Zhou, Shuo; Lu, Qing-sheng; Liu, Jian-zhong; Zhang, Peng

2011-03-01

To study therapeutic effects by using different oxygen therapies in rats with acute carbon dioxide poisoning, to select the best oxygen therapy technology for patients with acute carbon dioxide poisoning on the spot. Sixty healthy male Sprague-Dawley rats were randomized into normal control group, carbon dioxide exposure group, hyperbaric oxygen treatment group (pressure 2 ATA, FiO(2)100%), high concentration of atmospheric oxygen treatment group (FiO(2)50%), low concentration of atmospheric oxygen treatment group (FiO(2)33%). After treated with different oxygen in rats with acute carbon dioxide poisoning, arterial pH, PO2 and PCO2 of rats were detected, in addition observe pathological changes of lung tissue and brain tissue. The arterial pH (7.31 ± 0.06) and PO2 [(68.50 ± 15.02) mm Hg] of carbon dioxide exposure group were lower than those of control group [pH (7.42 ± 0.02) and PO2 (92.83 ± 8.27) mm Hg], PCO2 [(71.66 ± 12.10) mm Hg] was higher than that of control group [(48.25 ± 2.59) mm Hg] (P < 0.05); the arterial pH (hyperbaric oxygen treatment group 7.37 ± 0.02, high concentration of atmospheric oxygen treatment group 7.39 ± 0.03, low concentration of atmospheric oxygen treatment group 7.38 ± 0.02) and PO2 of oxygen treatment groups [hyperbaric oxygen treatment group, high concentration of atmospheric oxygen treatment group, low concentration of atmospheric oxygen treatment group were (82.25 ± 12.98), (84.75 ± 11.24), (83.75 ± 16.77) mm Hg, respectively] were higher than that of carbon dioxide exposure group, PCO2 [hyperbaric oxygen treatment group, high concentration of atmospheric oxygen treatment group, low concentration of atmospheric oxygen treatment group were (52.25 ± 4.95), (51.75 ± 4.82), (52.66 ± 5.61) mm Hg, respectively] was lower than that of carbon dioxide exposure group (P < 0.05); there was no significant difference of the arterial pH, PO2 and PCO2 between oxygen treatment groups and control group (P > 0.05); there was no significant difference of the arterial pH, PO2 and PCO2 among oxygen treatment groups (P > 0.05). There was large area of bleeding of lungs in rats with carbon dioxide poisoning, the bleeding of lungs in rats with high concentration of atmospheric oxygen treatment and low concentration of atmospheric oxygen treatment was better than the rats with carbon dioxide poisoning, there was no abnormal appearance of lungs in rats with hyperbaric oxygen treatment. The light microscope observation showed that there were diffuse bleeding and exudation of lungs in rats with carbon dioxide poisoning, the bleeding and exudation of lungs in rats with high concentration of atmospheric oxygen treatment and low concentration of atmospheric oxygen treatment were better than the rats with carbon dioxide poisoning, there were only minor bleeding and exudation of lungs in rats with hyperbaric oxygen treatment. There was no difference of brain in anatomy and microscopy among all groups, there were no significant bleeding, edema, cell degeneration and necrosis. Lung pathology in acute carbon dioxide poisoning rats with hyperbaric oxygen treatment is better than the rats with high concentration of atmospheric oxygen treatment and low concentration of atmospheric oxygen treatment, there is no significant difference of effect between high concentration of atmospheric oxygen treatment group and low concentration of atmospheric oxygen treatment group, however, the results of blood gas analysis and lung pathology than the exposure group improved, so qualified medical unit for hyperbaric oxygen therapy as soon as possible, hyperbaric oxygen treatment facilities in the absence of circumstances, the emergency treatment of early oxygen is also a good measure.

Transport of sulfur dioxide from the Asian Pacific Rim to the North Pacific troposphere

NASA Astrophysics Data System (ADS)

Thornton, Donald C.; Bandy, Alan R.; Blomquist, Byron W.; Talbot, Robert W.; Dibb, Jack E.

1997-12-01

The NASA Pacific Exploratory Mission over the Western Pacific Ocean (PEM-West B) field experiment provided an opportunity to study sulfur dioxide (SO2) in the troposphere over the western Pacific Ocean from the tropics to 60°N during February-March 1993. The large suite of chemical and physical measurements yielded a complex matrix in which to understand the distribution of sulfur dioxide over the western Pacific region. In contrast to the late summer period of Pacific Exploratory Mission-West A (PEM-West A) (1991) over this same area, SO2 showed little increase with altitude, and concentrations were much lower in the free troposphere than during the PEM-West B period. Volcanic impacts on the upper troposphere were again found as a result of deep convection in the tropics. Extensive emission of SO2 from the Pacific Rim land masses were primarily observed in the lower well-mixed part of the boundary layer but also in the upper part of the boundary layer. Analyses of the SO2 data with aerosol sulfate, beryllium-7, and lead-210 indicated that SO2 contributed to half or more of the observed total oxidized sulfur (SO2 plus aerosol sulfate) in free tropospheric air. The combined data set suggests that SO2 above 8.5 km is transported from the surface but with aerosol sulfate being removed more effectively than SO2. Cloud processing and rain appeared to be responsible for lower SO2 levels between 3 and 8.5 km than above or below this region.

Sulfur dioxide alleviates programmed cell death in barley aleurone by acting as an antioxidant

PubMed Central

Yang, Feng; Huang, Zhong-Qin; Tang, Jun; Hu, Kang-Di

2017-01-01

Sulfur dioxide (SO2), a gaseous signaling molecule in animal cells, has recently been found to play a physiological role in plants. Here we studied the role of SO2 in gibberellic acid (GA3)-induced programmed cell death (PCD) in barley (Hordeum vulgare L.) aleurone layers. The application of the SO2 donor (NaHSO3/Na2SO3, 1:3 M/M) effectively alleviated PCD in barley aleurone layers in a dose-dependent manner with an optimal concentration of 50 μM. Further investigations showed that SO2 reduced the accumulation of hydrogen peroxide (H2O2), superoxide anion (⋅O2−) and malondialdehyde (MDA) in aleurone layers. Moreover, the activities of antioxidant enzymes such as superoxide dismutase (SOD), catalase (CAT), ascorbate peroxidase (APX), glutathione reductase (GR) and guaiacol peroxidase (POD) were enhanced by SO2 donor treatment. Meanwhile, lipoxygenase (LOX) activity was attenuated by SO2 donor treatment. Furthermore, an induction of endogenous H2S and NO were also observed in SO2-treated aleurone layers, suggesting interactions of SO2 with other well-known signaling molecules. Taken together, we show that SO2 negatively regulated PCD by acting as an antioxidant to scavenge excessive reactive oxygen species (ROS) generated during PCD. PMID:29155872

Evaluation of GEOS-5 Sulfur Dioxide Simulations During the Frostburg, MD 2010 Field Campaign.

NASA Technical Reports Server (NTRS)

Buchard, V.; Da Silva, A. M.; Colarco, P.; Krotkov, N.; Dickerson, R. R.; Stehr, J. W.; Mount, G.; Spenei, E.; Arkinson, H. L.; He, H.

2013-01-01

Sulfur dioxide (SO2) is a major atmospheric pollutant with a strong anthropogenic component mostly produced by the combustion of fossil fuel and other industrial activities. As a precursor of sulfate aerosols that affect climate, air quality, and human health, this gas needs to be monitored on a global scale. Global climate and chemistry models including aerosol processes along with their radiative effects are important tools for climate and air quality research. Validation of these models against in-situ and satellite measurements is essential to ascertain the credibility of these models and to guide model improvements. In this study the Goddard Chemistry, Aerosol, Radiation, and Transport (GOCART) module running on-line inside the Goddard Earth Observing System version 5 (GEOS-5) model is used to simulate aerosol and SO2 concentrations. Data taken in November 2010 over Frostburg, Maryland during an SO2 field campaign involving ground instrumentation and aircraft are used to evaluate GEOS-5 simulated SO2 concentrations. Preliminary data analysis indicated the model overestimated surface SO2 concentration, which motivated the examination of mixing processes in the model and the specification of SO2 anthropogenic emission rates. As a result of this analysis, a revision of anthropogenic emission inventories in GEOS-5 was implemented, and the vertical placement of SO2 sources was updated. Results show that these revisions improve the model agreement with observations locally and in regions outside the area of this field campaign. In particular, we use the ground-based measurements collected by the United States Environmental Protection Agency (US EPA) for the year 2010 to evaluate the revised model simulations over North America.

Sensing Free Sulfur Dioxide in Wine

PubMed Central

Monro, Tanya M.; Moore, Rachel L.; Nguyen, Mai-Chi; Ebendorff-Heidepriem, Heike; Skouroumounis, George K.; Elsey, Gordon M.; Taylor, Dennis K.

2012-01-01

Sulfur dioxide (SO2) is important in the winemaking process as it aids in preventing microbial growth and the oxidation of wine. These processes and others consume the SO2 over time, resulting in wines with little SO2 protection. Furthermore, SO2 and sulfiting agents are known to be allergens to many individuals and for that reason their levels need to be monitored and regulated in final wine products. Many of the current techniques for monitoring SO2 in wine require the SO2 to be separated from the wine prior to analysis. This investigation demonstrates a technique capable of measuring free sulfite concentrations in low volume liquid samples in white wine. This approach adapts a known colorimetric reaction to a suspended core optical fiber sensing platform, and exploits the interaction between guided light located within the fiber voids and a mixture of the wine sample and a colorimetric analyte. We have shown that this technique enables measurements to be made without dilution of the wine samples, thus paving the way towards real time in situ wine monitoring. PMID:23112627

Spatiotemporal analysis of particulate matter, sulfur dioxide and carbon monoxide concentrations over the city of Rio de Janeiro, Brazil

NASA Astrophysics Data System (ADS)

Zeri, Marcelo; Oliveira-Júnior, José Francisco; Lyra, Gustavo Bastos

2011-09-01

Time series of pollutants and weather variables measured at four sites in the city of Rio de Janeiro, Brazil, between 2002 and 2004, were used to characterize temporal and spatial relationships of air pollution. Concentrations of particulate matter (PM10), sulfur dioxide (SO2) and carbon monoxide (CO) were compared to national and international standards. The annual median concentration of PM10 was higher than the standard set by the World Health Organization (WHO) on all sites and the 24 h means exceeded the standards on several occasions on two sites. SO2 and CO did not exceed the limits, but the daily maximum of CO in one of the stations was 27% higher on weekends compared to weekdays, due to increased activity in a nearby Convention Center. Air temperature and vapor pressure deficit have both presented the highest correlations with pollutant's concentrations. The concentrations of SO2 and CO were not correlated between sites, suggesting that local sources are more important to those pollutants compared to PM10. The time series of pollutants and air temperature were decomposed in time and frequency by wavelet analysis. The results revealed that the common variability of air temperature and PM10 is dominated by temporal scales of 1-8 days, time scales that are associated with the passage of weather events, such as cold fronts.

Material flows generated by pyromet copper smelting

USGS Publications Warehouse

Goonan, T.G.

2005-01-01

Copper production through smelting generates large volumes of material flows. As copper contained in ore becomes copper contained in concentrate to be fed into the smelting process, it leaves behind an altered landscape, sometimes mine waste, and always mill tailings. Copper concentrate, fluxing materials, fuels, oxygen, recyclables, scrap and water are inputs to the process. Dust (recycled), gases - containing carbon dioxide (CO2) (dissipated) and sulfur dioxide (SO2) (mostly collected, transformed and sold) and slag (discarded or sold) - are among the significant process outputs. This article reports estimates of the flows of these input/output materials for a particular set of smelters studied in some countries.

Soft X-ray-assisted detection method for airborne molecular contaminations (AMCs)

NASA Astrophysics Data System (ADS)

Kim, Changhyuk; Zuo, Zhili; Finger, Hartmut; Haep, Stefan; Asbach, Christof; Fissan, Heinz; Pui, David Y. H.

2015-03-01

Airborne molecular contaminations (AMCs) represent a wide range of gaseous contaminants in cleanrooms. Due to the unintentional nanoparticle or haze formation as well as doping caused by AMCs, improved monitoring and controlling methods for AMCs are urgent in the semiconductor industry. However, measuring ultra-low concentrations of AMCs in cleanrooms is difficult, especially, behind a gas filter. In this study, a novel detection method for AMCs, which is on-line, economical, and applicable for diverse AMCs, was developed by employing gas-to-particle conversion with soft X-ray, and then measuring the generated nanoparticles. Feasibility study of this method was conducted through the evaluations of granular-activated carbons (GACs), which are widely used AMC filter media. Sulfur dioxide (SO2) was used as an AMC for the feasibility study. Using this method, the ultra-low concentrations of SO2 behind GACs were determined in terms of concentrations of generated sulfuric acid (H2SO4) nanoparticles. By calculating SO2 concentrations from the nanoparticle concentrations using empirical correlation equations between them, remarkable sensitivity of this method to SO2 was shown, down to parts-per-trillions, which are too low to detect using commercial gas sensors. Also, the calculated SO2 concentrations showed good agreement with those measured simultaneously by a commercial SO2 monitor at parts-per-billions.

Long-term trends in airborne SO2 in an air quality monitoring station in Seoul, Korea, from 1987 to 2013.

PubMed

Khan, Azmatullah; Kim, Ki-Hyun; Szulejko, Jan E; Brown, Richard J C; Jeon, Eui-Chan; Oh, Jong-Min; Shin, Yong Soon; Adelodun, Adedeji A

2017-08-01

Atmospheric concentration of sulfur dioxide (SO 2 ) was intermittently measured at an air quality monitoring (AQM) station in the Yong-san district of Seoul, Korea, between 1987 and 2013. The SO 2 level was compared with other important pollutants concurrently measured, including methane (CH 4 ), carbon monoxide (CO), nitric oxide (NO), nitrogen dioxide (NO 2 ), ozone (O 3 ), and particulate matter (PM 10 ). If split into three different periods (period 1, 1987-1988, period 2, 1999-2000, and period 3, 2004-2013), the respective mean [SO 2 ] values (6.57 ± 4.29, 6.30 ± 2.44, and 5.29 ± 0.63 ppb) showed a slight reduction across the entire study period. The concentrations of SO 2 are found to be strongly correlated with other pollutants such as CO (r = 0.614, p = 0.02), which tracked reductions in reported emissions due to tighter emissions standards enacted by the South Korean government. There was also a clear seasonal trend in the SO 2 level, especially in periods 2 and 3, reflecting the combined effects of domestic heating by coal briquettes and meteorological conditions. Although only a 16% concentration reduction was achieved during the 27-year study duration, this is significant if one considers rapid urbanization, an 83.2% increase in population, and rapid industrialization that took place during that period. Since 1970, a network of air quality monitoring (AQM) stations has been operated by the Korean Ministry of Environment (KMOE) for routine nationwide monitoring of air pollutant concentrations in urban/suburban areas. To date, the information obtained from these stations has provided a platform for analyzing long-term trends of major pollutant species. In this study, we examined the long-term trends of SO 2 levels and relevant environmental parameters monitored continuously in the Yong-san district of Seoul between 1987 and 2013. The data were analyzed over various time scales (i.e., monthly, seasonal, and annual intervals). The results obtained from this study will allow us to assess the effectiveness of abatement strategy and to predict future concentrations trends in association with future abatement strategies and technologies.

Fluoride and sulfur dioxide indoor pollution situation and control in coal-burning endemic area in Zhaotong, Yunnan, China

NASA Astrophysics Data System (ADS)

Liu, Yonglin; Luo, Kunli; Li, Ling; Shahid, Muhammad Zeeshaan

2013-10-01

The presented study aims to investigate the gaseous fluoride and sulfur dioxide (SO2) pollution level in the kitchen, traditional flue-curing barn and outdoor environment and to find economically feasible method to reduce fluorine and sulfur release. The gaseous fluoride and SO2 concentrations in air of outdoor environment, kitchen and traditional flue-curing barn were determined in 56 households in coal-burning endemic fluorosis areas of Zhaotong. Among these, 21 households in Yujiawan Village, Zhenxiong County, Zhaotong City were chosen for this experiment to reduce gaseous fluoride and SO2 concentration in traditional flue-curing barn air by using calcined dolomitic siliceous limestone (CDSL) instead of clay mixed with coal. The result showed that: (1) gaseous fluoride and SO2 concentration in the outdoor air in Mangbu Township area was 0.51 μg dm-2ṡday and <0.05 mg m-3, respectively and in Xiaolongdong Township was 2.7 μg dm-2 day and <0.05 mg m-3, respectively while in Zhaotong City these concentration were lower than the ambient air standard (3 μg dm-2ṡday and 0.5 mg m-3, respectively). (2) The indoor gaseous fluoride concentration (3.7 μg m-3) in air of kitchen with the improved coal stove was within the reference value (10 μg m-3); SO2 concentration (0.94 mg m-3) in kitchen air had decline, but its concentration was still higher than indoor air quality standard (0.5 mg m-3). (3) Average concentration of gaseous fluoride and SO2 in air of traditional flue-curing barn of Xiaolongdong Township was 7.2 μg m-3 and 6.8 mg m-3 respectively, and in Yujiawan village were 10.1 μg m-3 and 14.4 mg m-3, respectively. (4) After using the calcined dolomitic siliceous limestone instead of clay mixed with coal, gaseous fluoride and SO2 concentration in the traditional flue-curing barn air decreased of 45% and 91%, respectively. The gaseous fluoride and SO2 pollution in the traditional flue-curing barn is very serious. The corn and chili baked by open stoves in traditional flue-curing barn (baking room) was also seriously polluted by fluoride and sulfur. After using the calcined dolomitic siliceous limestone instead of clay mixed with coal, gaseous fluoride and SO2 concentration in the traditional flue-curing barn air have declined markedly. The way of adding calcined dolomitic siliceous limestone instead of clay as a binder for briquette-making is an economically feasible way to control the indoor pollution of fluorine and sulfur in coal-burning endemic in Zhaotong, Yunnan.

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

Code of Federal Regulations, 2012 CFR

2012-07-01

... 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... contains total potential sulfur emissions in excess of 26 ng SO2/J (0.060 lb SO2/MMBtu) heat input. If your...

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

Code of Federal Regulations, 2010 CFR

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... contains total potential sulfur emissions in excess of 26 ng SO2/J (0.060 lb SO2/MMBtu) heat input. If your...

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

Code of Federal Regulations, 2011 CFR

2011-07-01

... 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... contains total potential sulfur emissions in excess of 26 ng SO2/J (0.060 lb SO2/MMBtu) heat input. If your...

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

Code of Federal Regulations, 2013 CFR

2013-07-01

... 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... contains total potential sulfur emissions in excess of 26 ng SO2/J (0.060 lb SO2/MMBtu) heat input. If your...

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

Code of Federal Regulations, 2014 CFR

2014-07-01

... 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... contains total potential sulfur emissions in excess of 26 ng SO2/J (0.060 lb SO2/MMBtu) heat input. If your...

Health risk of inhalation exposure to sub-10 µm particulate matter and gaseous pollutants in an urban-industrial area in South Africa: an ecological study

PubMed Central

Morakinyo, Oyewale Mayowa; Adebowale, Ayo Stephen; Mokgobu, Matlou Ingrid; Mukhola, Murembiwa Stanley

2017-01-01

Objective To assess the health risks associated with exposure to particulate matter (PM10), sulphur dioxide (SO2), nitrogen dioxide (NO2), carbon monoxide (CO) and ozone (O3). Design The study is an ecological study that used the year 2014 hourly ambient pollution data. Setting The study was conducted in an industrial area located in Pretoria West, South Africa. The area accommodates a coal-fired power station, metallurgical industries such as a coke plant and a manganese smelter. Data and method Estimate of possible health risks from exposure to airborne PM10, SO2, NO2, CO and O3 was performed using the US Environmental Protection Agency human health risk assessment framework. A scenario-assessment approach where normal (average exposure) and worst-case (continuous exposure) scenarios were developed for intermediate (24-hour) and chronic (annual) exposure periods for different exposure groups (infants, children, adults). The normal acute (1-hour) exposure to these pollutants was also determined. Outcome measures Presence or absence of adverse health effects from exposure to airborne pollutants. Results Average annual ambient concentration of PM10, NO2 and SO2 recorded was 48.3±43.4, 11.50±11.6 and 18.68±25.4 µg/m3, respectively, whereas the South African National Ambient Air Quality recommended 40, 40 and 50 µg/m3 for PM10, NO2 and SO2, respectively. Exposure to an hour's concentration of NO2, SO2, CO and O3, an 8-hour concentration of CO and O3, and a 24-hour concentration of PM10, NO2 and SO2 will not likely produce adverse effects to sensitive exposed groups. However, infants and children, rather than adults, are more likely to be affected. Moreover, for chronic annual exposure, PM10, NO2 and SO2 posed a health risk to sensitive individuals, with the severity of risk varying across exposed groups. Conclusions Long-term chronic exposure to airborne PM10, NO2 and SO2 pollutants may result in health risks among the study population. PMID:28289048

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

Code of Federal Regulations, 2012 CFR

2012-07-01

... 40 Protection of Environment 7 2012-07-01 2012-07-01 false Standards for sulfur dioxide (SO2). 60... Steam Generating Units § 60.43Da Standards for sulfur dioxide (SO2). (a) On and after the date on which... the percent reduction requirement is determined on a 24-hour basis. (d) Sulfur dioxide emissions are...

Distillation and detection of SO2 using a microfluidic chip.

PubMed

Ju, Wei-Jhong; Fu, Lung-Ming; Yang, Ruey-Jen; Lee, Chia-Lun

2012-02-07

A miniaturized distillation system is presented for separating sulfurous acid (H(2)SO(3)) into sulfur dioxide (SO(2)) and water (H(2)O). The major components of the proposed system include a microfluidic distillation chip, a power control module, and a carrier gas pressure control module. The microfluidic chip is patterned using a commercial CO(2) laser and comprises a serpentine channel, a heating zone, a buffer zone, a cooling zone, and a collection tank. In the proposed device, the H(2)SO(3) solution is injected into the microfluidic chip and is separated into SO(2) and H(2)O via an appropriate control of the distillation time and temperature. The gaseous SO(2) is then transported into the collection chamber by the carrier gas and is mixed with DI water. Finally, the SO(2) concentration is deduced from the absorbance measurements obtained using a spectrophotometer. The experimental results show that a correlation coefficient of R(2) = 0.9981 and a distillation efficiency as high as 94.6% are obtained for H(2)SO(3) solutions with SO(2) concentrations in the range of 100-500 ppm. The SO(2) concentrations of two commercial red wines are successfully detected using the developed device. Overall, the results presented in this study show that the proposed system provides a compact and reliable tool for SO(2) concentration measurement purposes.

[Effect of air pollution on health service demand of the elderly and middle-age patients with hypertension, cardiovascular and cerebrovascular diseases: based on analysis of data from CHARLS].

PubMed

Shan, J; Li, H Y; Liu, G F; Yang, X; Dong, W; Jian, W Y; Deng, F R; Guo, X B

2016-06-18

To study the association of air pollution with health service demand of the elderly and middle-age patients with cardiovascular and cerebrovascular diseases, and to provide a scientific basis for development of environmental protection policy and health service policy of the Chinese government. This study included survey data on self-evaluated health, outpatient service demand and inpatient service demand of the patients with hypertension, heart disease and stroke in 62 cities of 17 provinces from China Health and Retirement Longitudinal Study (CHARLS) in 2011 and 2013, and combined it with the data on the annual concentrations of inhalable particulate matter (PM(10)), sulfur dioxide(SO(2)) and nitrogen dioxide (NO(2)) of those provinces and cities. Conditional Logistic regression was carried out to assess the possible effects of air pollutants on self-evaluated health and health service utilization. The results showed that turning points existed in the effects of concentrations of NO(2) and SO(2) on the health service demand of the patients with hypertension, heart disease and stroke. The inpatient service demand of the hypertension patients increased with NO(2) concentration when it was lower than 35.1 μg/m(3) and decreased with NO(2) concentration for higher value. Self-evaluated health of the patients with heart disease and stroke decreased with SO(2) concentration when it was lower than 63.8 μg/m(3) and increased with SO(2) concentration for higher value. In addition, no evidence was found for the association between PM(10) and health service demand. Air pollution may have effects on health service demand of the patients with hypertension,cardiovascular and cerebrovascular diseases, and different air pollutants at high or low concentration may have different health effects.

Interspecific differences in the effects of sulfur dioxide on angiosperm sexual reproduction

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

DuBay, D.T.

1981-01-01

The major objective of this study was to test the potential direct effects of SO/sub 2/ on sexual reproduction in several plant species with different reproductive structures and processes. In marked contrast to the sensitivity to SO/sub 2/ reported by other investigators for pollen germination and pollen tube growth in vitro, and recorded for Lepidium virginicum in this study, 4 of 5 species tested were tolerant with respect to fruit and seed set after exposure to 0.6 ppm SO/sub 2/ for 8 hours during flowering. Seed set in the one sensitive species, Geranium carolinianum, was reduced 40% from the controlmore » after exposure to SO/sub 2/, but only when relative humidity (RH) was at or above 90%. The effect of SO/sub 2/ on Lepidium pollen germination in vitro was greater than the effect of SO/sub 2/ on sexual reproduction in vivo. Sulfur dioxide reduced pollen germination in vitro 94% from the control. The same concentration of SO/sub 2/, at 90% Rh, reduced pollen germination in vivo 50% from the control, but had no effect on seed set. Predictions of effects of SO/sub 2/ on reproduction in vivo based on effects of SO/sub 2/ on pollen germination and pollen tube growth in vitro are not valid.« less

Dispersion modelling and measurement of emissions from the co-combustion of meat and bone meal with peat in a fluidised bed.

PubMed

Cummins, Enda J; McDonnell, Kevin P; Ward, Shane M

2006-05-01

Due to the ban on meat and bone meal (MBM) as an animal feed, combustion with energy recovery has been considered a viable alternative usage for the mounting stocks of MBM. The effects of the co-combustion of MBM and peat on flue gas emissions and fluidisation were studied using a bubbling fluidised bed (BFB) test facility (20 kW). The dispersion of emissions such as nitrogen dioxide (NO2), sulphur dioxide (SO2), carbon monoxide (CO), hydrogen chloride (HCl) and particulates was investigated for a proposed site and compared to the relevant national and international regulations. Concentrations of NO2, CO and HCl were less than 10% of legislative and guideline thresholds while ground level concentrations of SO2 were also below relevant EU and world guidelines. The results indicate the potential for using MBM as a co-fuel with peat in a BFB while maintaining high air quality standards.

Peak exposures in aluminium potrooms: instrument development and field calibration.

PubMed

Carter, Stephanie R; Seixas, Noah S; Thompson, Mary Lou; Yost, Michael G

2004-11-01

Aluminium smelter potrooms are unique in that workplace exposures to hydrogen fluoride (HF), sulfur dioxide (SO2), and particulate matter occur simultaneously for some tasks. The peak exposures to these contaminants are of increasing interest in discovering the etiology of respiratory health effects. While a variety of direct-reading instruments are available for sulfur dioxide and particulate matter, only a few exist for hydrogen fluoride. The sensors in these HF instruments have a cross-sensitivity to sulfur dioxide making it difficult to monitor HF in an environment that also contains SO2. To overcome this problem, we assessed the simultaneous use of two electrochemical instruments: one with a SO2 sensor that does not respond to HF and the second with a hydrogen fluoride sensor that responds to both HF and SO2 in a 1 : 1 ratio, termed 'total acid gas'. The difference in the response between the two instruments should indicate the HF concentration: [HF + SO2] minus SO2 equals HF. The performance characteristics of this sampling train were evaluated in the laboratory through the generation of both HF and SO2 with permeation tubes. The response and recovery times for the SO2 only instrument were acceptable (6 and 15 s, respectively), but the "total acid gas" instrument exhibited both slow response and slow recovery approaching three and six min. The association between the traditional integrated filter sampling method and the direct-reading instrument for SO2 is 0.80 (Spearman's rho). The use of the digital filter strengthens the association between the HF direct-reading instrument and the integrated samples from 0.41 to 0.68.

Controlled exposure of volunteers with chronic obstructive pulmonary disease to sulfur dioxide

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

Linn, W.S.; Fischer, D.A.; Shamoo, D.A.

1985-08-01

Twenty-four volunteers with chronic obstructive pulmonary disease (COPD) were exposed to sulfur dioxide (SO/sub 2/) at 0, 0.4, and 0.8 ppm in an environmental control chamber. Exposures lasted 1 hr and included two 15-min exercise periods (mean exercise ventilation rate 18 liter/min). Pulmonary mechanical function was evaluated before exposures, after initial exercise, and at the end of exposure. Blood oxygenation was measured by ear oximetry before exposure and during the second exercise period. Symptoms were recorded throughout exposure periods and for 1 week afterward. No statistically significant changes in physiology or symptoms could be attributed to SO/sub 2/ exposure. Oldermore » adults with COPD seem less reactive to a given concentration of SO/sub 2/ than heavily exercising young adult asthmatics. This may be due to lower ventilation rates (i.e., lower SO/sub 2/ dose rates) and/or to lower airway reactivity in the COPD group.« less

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

Federal Register 2010, 2011, 2012, 2013, 2014

2013-08-05

... Air Quality Designations for the 2010 Sulfur Dioxide (SO[bdi2]) Primary National Ambient Air Quality... air quality designations for certain areas in the United States for the 2010 primary Sulfur Dioxide... of this document? III. What is sulfur dioxide? IV. What is the 2010 SO 2 NAAQS and what are the...

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

Code of Federal Regulations, 2011 CFR

2011-07-01

... 40 Protection of Environment 6 2011-07-01 2011-07-01 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... reduction requirement is determined on a 24-hour basis. (d) Sulfur dioxide emissions are limited to 520 ng/J...

Effectiveness of national air pollution control policies on the air quality in metropolitan areas of China.

PubMed

Wang, Shuxiao; Xing, Jia; Zhao, Bin; Jang, Carey; Hao, Jiming

2014-01-01

Understanding the effectiveness of national air pollution controls is important for control policy design to improve the future air quality in China. This study evaluated the effectiveness of major national control policies implemented recently in China through a modeling analysis. The sulfur dioxide (SO2) control policy during the 11th Five Year Plan period (2006-2010) had succeeded in reducing the national SO2 emission in 2010 by 14% from its 2005 level, which correspondingly reduced ambient SO2 and sulfate (SO4(2-)) concentrations by 13%-15% and 8%-10% respectively over east China. The nitrogen oxides (NO(x)) control policy during the 12th Five Year Plan period (2011-2015) targets the reduction of the national NO(x) emission in 2015 by 10% on the basis of 2010. The simulation results suggest that such a reduction in NO(x) emission will reduce the ambient nitrogen dioxide (NO2), nitrate (NO3(-)), 1-hr maxima ozone (O3) concentrations and total nitrogen deposition by 8%, 3%-14%, 2% and 2%-4%, respectively over east China. The application of new emission standards for power plants will further reduce the NO2, NO3(-), 1-hr maxima O(3 concentrations and total nitrogen deposition by 2%-4%, 1%-6%, 0-2% and 1%-2%, respectively. Sensitivity analysis was conducted to evaluate the inter-provincial impacts of emission reduction in Beijing-Tianjin-Hebei and the Yangtze River Delta, which indicated the need to implement joint regional air pollution control.

Assessing hazards to aviation from sulfur dioxide emitted by explosive Icelandic eruptions

NASA Astrophysics Data System (ADS)

Schmidt, Anja; Witham, Claire S.; Theys, Nicolas; Richards, Nigel A. D.; Thordarson, Thorvaldur; Szpek, Kate; Feng, Wuhu; Hort, Matthew C.; Woolley, Alan M.; Jones, Andrew R.; Redington, Alison L.; Johnson, Ben T.; Hayward, Chris L.; Carslaw, Kenneth S.

2014-12-01

Volcanic eruptions take place in Iceland about once every 3 to 5 years. Ash emissions from these eruptions can cause significant disruption to air traffic over Europe and the North Atlantic as is evident from the 2010 eruption of Eyjafjallajökull. Sulfur dioxide (SO2) is also emitted by volcanoes, but there are no criteria to define when airspace is considered hazardous or nonhazardous. However, SO2 is a well-known ground-level pollutant that can have detrimental effects on human health. We have used the United Kingdom Met Office's NAME (Numerical Atmospheric-dispersion Modelling Environment) model to simulate SO2 mass concentrations that could occur in European and North Atlantic airspace for a range of hypothetical explosive eruptions in Iceland with a probability to occur about once every 3 to 5 years. Model performance was evaluated for the 2010 Eyjafjallajökull summit eruption against SO2 vertical column density retrievals from the Ozone Monitoring Instrument and in situ measurements from the United Kingdom Facility for Airborne Atmospheric Measurements research aircraft. We show that at no time during the 2010 Eyjafjallajökull eruption did SO2 mass concentrations at flight altitudes violate European air quality standards. In contrast, during a hypothetical short-duration explosive eruption similar to Hekla in 2000 (emitting 0.2 Tg of SO2 within 2 h, or an average SO2 release rate 250 times that of Eyjafjallajökull 2010), simulated SO2 concentrations are greater than 1063 µg/m3 for about 48 h in a small area of European and North Atlantic airspace. By calculating the occurrence of aircraft encounters with the volcanic plume of a short-duration eruption, we show that a 15 min or longer exposure of aircraft and passengers to concentrations ≥500 µg/m3 has a probability of about 0.1%. Although exposure of humans to such concentrations may lead to irritations to the eyes, nose and, throat and cause increased airway resistance even in healthy individuals, the risk is very low. However, the fact that volcanic ash and sulfur species are not always collocated and that passenger comfort could be compromised might be incentives to provide real-time information on the presence or absence of volcanic SO2. Such information could aid aviation risk management during and after volcanic eruptions.

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

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

Koenig, J.Q.; Covert, D.S.; Hanley, Q.S.

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

A Time-Series Study of the Effect of Air Pollution on Outpatient Visits for Acne Vulgaris in Beijing.

PubMed

Liu, Wei; Pan, Xiaochuan; Vierkötter, Andrea; Guo, Qun; Wang, Xuying; Wang, Qiaowei; Seité, Sophie; Moyal, Dominique; Schikowski, Tamara; Krutmann, Jean

2018-01-01

There is increasing evidence that exposure to air pollutants, including particulate matter (PM2.5, PM10), nitrogen dioxide (NO2), and sulfur dioxide (SO2), might aggravate preexisting skin diseases such as eczema and urticaria. Here we investigated if a possible link exists between air pollution and acne vulgaris. We assessed the association between ambient air pollutant concentrations and the number of visits of patients for acne vulgaris to a dermatological outpatient clinic in Beijing, China, from April 1, 2012 to April 30, 2014. In this time period, 59,325 outpatient visits were recorded because of acne vulgaris. Daily air pollution parameters for PM10, PM2.5, SO2, and NO2 were obtained from the Beijing Municipal Environmental Monitoring Center. Increased concentrations of ambient PM2.5, PM10, and NO2 were significantly associated with increased numbers of outpatient visits for acne vulgaris over the 2 years. These effects could be observed for NO2 in a single-pollutant model and for PM2.5, PM10, and NO2 in 2-pollutant models, which are closer to real-life exposure. Of note, these effects were specific because they were not observed for increased SO2 concentrations, which even showed negative correlations in all test models. This study provides indirect evidence for a link between acne vulgaris and air pollution. © 2018 S. Karger AG, Basel.

The relationship between odour annoyance scores and modelled ambient air pollution in Sarnia, "Chemical Valley", Ontario.

PubMed

Atari, Dominic Odwa; Luginaah, Isaac N; Fung, Karen

2009-10-01

This study aimed at establishing the relationship between annoyance scores and modelled air pollution in "Chemical Valley", Sarnia, Ontario (Canada). Annoyance scores were taken from a community health survey (N = 774); and respondents' exposure to nitrogen dioxide (NO(2)) and sulphur dioxide (SO(2)) were estimated using land use regression (LUR) models. The associations were examined by univariate analysis while multivariate logistic regression was used to examine the determinants of odour annoyance. The results showed that odour annoyance was significantly correlated to modelled pollutants at the individual (NO(2), r = 0.15; SO(2), r = 0.13) and census tract (NO(2), r = 0.56; SO(2), r = 0.67) levels. The exposure-response relationships show that residents of Sarnia react to very low pollution concentrations levels even if they are within the Ontario ambient air quality criteria. The study found that exposure to high NO(2) and SO(2) concentrations, gender, and perception of health effects were significant determinants of individual odour annoyance reporting. The observed association between odour annoyance and modelled ambient pollution suggest that individual and census tract level annoyance scores may serve as proxies for air quality in exposed communities because they capture the within area spatial variability of pollution. However, questionnaire-based odour annoyance scores need to be validated longitudinally and across different scales if they are to be adopted for use at the national level.

Air pollution and hospital admissions for respiratory and cardiovascular diseases in Hong Kong

PubMed Central

Wong, T. W.; Lau, T. S.; Yu, T. S.; Neller, A.; Wong, S. L.; Tam, W.; Pang, S. W.

1999-01-01

OBJECTIVE: To investigate short term effects of concentrations of pollutants in ambient air on hospital admissions for cardiovascular and respiratory diseases in Hong Kong. METHODS: Retrospective ecological study. A Poisson regression was performed of concentrations of daily air pollutant on daily counts of emergency hospital admissions in 12 major hospitals. The effects of time trend, season, and other cyclical factors, temperature, and humidity were accounted for. Autocorrelation and overdispersion were corrected. Daily concentrations of nitrogen dioxide (NO2), sulphur dioxide (SO2), ozone (O3), and particulate matter < 10 microns in aerodynamic diameter (PM10) were obtained from seven air monitoring stations in Hong Kong in 1994 and 1995. Relative risks (RR) of respiratory and cardiovascular disease admissions (for an increase of 10 micrograms/m3 in concentration of air pollutant) were calculated. RESULTS: Significant associations were found between hospital admissions for all respiratory diseases, all cardiovascular diseases, chronic obstructive pulmonary diseases, and heart failure and the concentrations of all four pollutants. Admissions for asthma, pneumonia, and influenza were significantly associated with NO2, O3, and PM10. Relative risk (RR) for admissions for respiratory disease for the four pollutants ranged from 1.013 (for SO2) to 1.022 (for O3), and for admissions for cardiovascular disease, from 1.006 (for PM10) to 1.016 (for SO2). Those aged > or = 65 years were at higher risk. Significant positive interactions were detected between NO2, O3, and PM10, and between O3 and winter months. CONCLUSIONS: Adverse health effects are evident at current ambient concentrations of air pollutants. Further reduction in air pollution is necessary to protect the health of the community, especially that of the high risk group.   PMID:10658547

Impacts of Four SO2 Oxidation Pathways on Wintertime Sulfate Concentrations

NASA Astrophysics Data System (ADS)

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 fine particles enhances sulfate only over parts of China, and SO2 oxidation by NO2 in aerosol water enhances sulfate only over parts of China by >5%. We will present a detailed analysis of the results and a comparison of model predictions with available observed data.

Evaluation of Sulfur Dioxide (SO2) Simulations with the GEOS-5/ GOCART Model during the Frostburg/DISCOVER-AQ Field Campaigns

NASA Astrophysics Data System (ADS)

Buchard-Marchant, V.; da Silva, A.; Colarco, P. R.; Krotkov, N. A.; Dickerson, R. R.; Stehr, J. W.; Spinei, E.; Mount, G. H.; Krask, D.

2011-12-01

Sulfur dioxide (SO2) is a major atmospheric pollutant, with a strong anthropogenic component mostly produced by the combustion of fossil fuel and other industrial activities. As a precursor of sulfate aerosols that affect climate, air quality and human health, this gas needs to be monitored on a global scale. Global climate and chemistry models including aerosol processes along with their radiative effects are important tools for climate and air quality research. Validation of these models against in-situ and satellite measurements are essential to ascertain the credibility of these models and to guide model improvements. In this study the Goddard Chemistry, Aerosol, Radiation, and Transport (GOCART) module running on-line inside the Goddard Earth Observing System version 5 (GEOS-5) model is used to simulate aerosol and SO2 concentrations. The global GEOS-5 system runs at a nominal 25 km horizontal resolution with 72 vertical levels; a comprehensive atmospheric data assimilation system is used to constrain the meteorological state of the model. Data taken over Maryland in the UM's Frostburg (November 2010) and NASA DISCOVER-AQ (July 2011) field campaigns are used to evaluate the GEOS-5 SO2 concentrations. In this presentation we show comparisons of simulated and measured SO2 concentration, using airborne and ground-based data sets, as well as data from the space-based OMI instrument. Preliminary data analysis indicated the model's overestimation of SO2 concentration at the surface, leading to a close examination of mixing processes in the model and the specification of SO2 anthropogenic emission rates. As a result of this analysis, we have implemented a revision of anthropogenic emission inventories in GEOS-5, and updated the vertical placement of SO2 sources. In this presentation we show how these revisions improve the model agreement with observations not only locally but also in regions outside the area of these field campaigns. In particular, we use the ground-based measurements from the Environmental Protection Agency (EPA) for the year 2010 to evaluate the revised model simulations over North America.

Potential flue gas impurities in carbon dioxide streams separated from coal-fired power plants.

PubMed

Lee, Joo-Youp; Keener, Tim C; Yang, Y Jeffery

2009-06-01

For geological sequestration of carbon dioxide (CO2) separated from pulverized coal combustion flue gas, it is necessary to adequately evaluate the potential impacts of flue gas impurities on groundwater aquifers in the case of the CO2 leakage from its storage sites. This study estimated the flue gas impurities to be included in the CO2 stream separated from a CO2 control unit for a different combination of air pollution control devices and different flue gas compositions. Specifically, the levels of acid gases and mercury vapor were estimated for the monoethanolamine (MEA)-based absorption process on the basis of published performance parameters of existing systems. Among the flue gas constituents considered, sulfur dioxide (SO2) is known to have the most adverse impact on MEA absorption. When a flue gas contains 3000 parts per million by volume (ppmv) SO2 and a wet flue gas desulfurization system achieves its 95% removal, approximately 2400 parts per million by weight (ppmw) SO2 could be included in the separated CO2 stream. In addition, the estimated concentration level was reduced to as low as 135 ppmw for the SO2 of less than 10 ppmv in the flue gas entering the MEA unit. Furthermore, heat-stable salt formation could further reduce the SO2 concentration below 40 ppmw in the separated CO2 stream. In this study, it is realized that the formation rates of heat-stable salts in MEA solution are not readily available in the literature and are critical to estimating the levels and compositions of flue gas impurities in sequestered CO2 streams. In addition to SO2, mercury, and other impurities in separated CO2 streams could vary depending on pollutant removal at the power plants and impose potential impacts on groundwater. Such a variation and related process control in the upstream management of carbon separation have implications for groundwater protection at carbon sequestration sites and warrant necessary considerations in overall sequestration planning, engineering, and management.

Development of an Ultra-Violet Digital Camera for Volcanic Sulfur Dioxide Imaging

NASA Astrophysics Data System (ADS)

Bluth, G. J.; Shannon, J. M.; Watson, I. M.; Prata, F. J.; Realmuto, V. J.

2006-12-01

In an effort to improve monitoring of passive volcano degassing, we have constructed and tested a digital camera for quantifying the sulfur dioxide (SO2) content of volcanic plumes. The camera utilizes a bandpass filter to collect photons in the ultra-violet (UV) region where SO2 selectively absorbs UV light. SO2 is quantified by imaging calibration cells of known SO2 concentrations. Images of volcanic SO2 plumes were collected at four active volcanoes with persistent passive degassing: Villarrica, located in Chile, and Santiaguito, Fuego, and Pacaya, located in Guatemala. Images were collected from distances ranging between 4 and 28 km away, with crisp detection up to approximately 16 km. Camera set-up time in the field ranges from 5-10 minutes and images can be recorded in as rapidly as 10-second intervals. Variable in-plume concentrations can be observed and accurate plume speeds (or rise rates) can readily be determined by tracing individual portions of the plume within sequential images. Initial fluxes computed from camera images require a correction for the effects of environmental light scattered into the field of view. At Fuego volcano, simultaneous measurements of corrected SO2 fluxes with the camera and a Correlation Spectrometer (COSPEC) agreed within 25 percent. Experiments at the other sites were equally encouraging, and demonstrated the camera's ability to detect SO2 under demanding meteorological conditions. This early work has shown great success in imaging SO2 plumes and offers promise for volcano monitoring due to its rapid deployment and data processing capabilities, relatively low cost, and improved interpretation afforded by synoptic plume coverage from a range of distances.

Improvement of wine aromatic quality using mixtures of lysozyme and dimethyl dicarbonate, with low SO2 concentration.

PubMed

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.

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

PubMed

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].

40 CFR 60.42c - Standard for sulfur dioxide (SO2).

Code of Federal Regulations, 2014 CFR

2014-07-01

... 40 Protection of Environment 7 2014-07-01 2014-07-01 false Standard for sulfur dioxide (SO2). 60...-Commercial-Institutional Steam Generating Units § 60.42c Standard for sulfur dioxide (SO2). (a) Except as... percent sulfur. The percent reduction requirements are not applicable to affected facilities under this...

40 CFR 60.42c - Standard for sulfur dioxide (SO2).

Code of Federal Regulations, 2012 CFR

2012-07-01

... 40 Protection of Environment 7 2012-07-01 2012-07-01 false Standard for sulfur dioxide (SO2). 60...-Commercial-Institutional Steam Generating Units § 60.42c Standard for sulfur dioxide (SO2). (a) Except as... percent sulfur. The percent reduction requirements are not applicable to affected facilities under this...

40 CFR 60.42c - Standard for sulfur dioxide (SO2).

Code of Federal Regulations, 2013 CFR

2013-07-01

... 40 Protection of Environment 7 2013-07-01 2013-07-01 false Standard for sulfur dioxide (SO2). 60...-Commercial-Institutional Steam Generating Units § 60.42c Standard for sulfur dioxide (SO2). (a) Except as... percent sulfur. The percent reduction requirements are not applicable to affected facilities under this...

40 CFR 60.42c - Standard for sulfur dioxide (SO2).

Code of Federal Regulations, 2011 CFR

2011-07-01

... 40 Protection of Environment 6 2011-07-01 2011-07-01 false Standard for sulfur dioxide (SO2). 60...-Commercial-Institutional Steam Generating Units § 60.42c Standard for sulfur dioxide (SO2). (a) Except as... sulfur. The percent reduction requirements are not applicable to affected facilities under this paragraph...

REGIONAL TRENDS IN RURAL SULFUR CONCENTRATIONS

EPA Science Inventory

This paper presents an analysis of trends in atmospheric concentrations of sulfur dioxide (SO,) and particulate sulfate (SO42-) at rural monitoring sites in the Clean Air Act Status and Trends Monitoring Network (CASTNet) from 1990 to 1999. A two-stage approach is used to estimat...

Significant geographic gradients in particulate sulfate over Japan determined from multiple-site measurements and a chemical transport model: Impacts of transboundary pollution from the Asian continent

NASA Astrophysics Data System (ADS)

Aikawa, Masahide; Ohara, Toshimasa; Hiraki, Takatoshi; Oishi, Okihiro; Tsuji, Akihiro; Yamagami, Makiko; Murano, Kentaro; Mukai, Hitoshi

2010-01-01

We found a significant geographic gradient (longitudinal and latitudinal) in the sulfate (SO 42-) concentrations measured at multiple sites over the East Asian Pacific Rim region. Furthermore, the observed gradient was well reproduced by a regional chemical transport model. The observed and modeled SO 42- concentrations were higher at the sites closer to the Asian continent. The concentrations of SO 42- from China as calculated by the model also showed the fundamental features of the longitudinal/latitudinal gradient. The proportional contribution of Chinese SO 42- to the total in Japan throughout the year was above 50-70% in the control case, using data for Chinese sulfur dioxide (SO 2) emission from the Regional Emission Inventory in Asia (40-60% in the low Chinese emissions case, using Chinese SO 2 emissions data from the State Environmental Protection Administration of China), with a winter maximum of approximately 65-80%, although the actual concentrations of SO 42- from China were highest in summer. The multiple-site measurements and the model analysis strongly suggest that the SO 42- concentrations in Japan were influenced by the outflow from the Asian continent, and this influence was greatest in the areas closer to the Asian continent. In contrast, we found no longitudinal/latitudinal gradient in SO 2 concentrations; instead SO 2 concentrations were significantly correlated with local SO 2 emissions. Our results show that large amounts of particulate sulfate are transported over long distances from the East Asian Pacific Rim region, and consequently the SO 42- concentrations in Japan are controlled by the transboundary outflow from the Asian continent.

77 FR 2466 - Approval, Disapproval and Promulgation of Air Quality Implementation Plans; Colorado: Smoke...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-01-18

..., Disapproval and Promulgation of Air Quality Implementation Plans; Colorado: Smoke, Opacity and Sulfur Dioxide... Carbon Monoxide, NO 2 mean Nitrogen Dioxide and SO 2 mean Sulfur Dioxide. The initials BACT mean Best.... Summary of SIP Revisions Colorado's Regulation 1 governs opacity, particulates, sulfur dioxide (SO 2...

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

Springston, Stephen R.

The Sulfur Dioxide Analyzer measures sulfur dioxide based on absorbance of UV light at one wavelength by SO 2 molecules which then decay to a lower energy state by emitting UV light at a longer wavelength. Specifically, SO 2 + hυ1 →SO 2 *→SO 2 + hυ2 The emitted light is proportional to the concentration of SO 2 in the optical cell. External communication with the analyzer is available through an Ethernet port configured through the instrument network of the AOS systems. The Model 43i-TLE is part of the i-series of Thermo Scientific instruments. The i-series instruments are designed tomore » interface with external computers through the proprietary Thermo Scientific iPort Software. However, this software is somewhat cumbersome and inflexible. Brookhaven National Laboratory (BNL) has written an interface program in National Instruments LabView that both controls the Model 43i-TLE Analyzer AND queries the unit for all measurement and housekeeping data. The LabView vi (the software program written by BNL) ingests all raw data from the instrument and outputs raw data files in a uniform data format similar to other instruments in the AOS and described more fully in Section 6.0 below.« less

Control of Nitrogen Dioxide in Stack Emission by Reaction with Ammonia

NASA Technical Reports Server (NTRS)

Metzler, A. J.; Stevenson, E. F.

1970-01-01

The development of an acid base gas-phase reaction system which utilizes anhydrous ammonia as the reactant to remove nitrogen dioxide from hydrazine-nitrogen tetroxide rocket combustion exhaust is reported. This reaction reduced NO2 levels in exhaust emissions so that the resulting stack emission is completely white instead of the earlier observed typical reddish-brown coloration. Preliminary analyses indicate the importance of reaction time and ammonia concentration on removal efficiency and elimination of the health hazard to individuals with respiratory problems.

Distributions of SO2 and NO2 in the lower atmosphere of an industrial area in Bhutan.

PubMed

Subba, Jas Raj; Thammakhet, Chongdee; Thavarungkul, Panote; Kanatharana, Proespichaya

2016-12-05

Two important air pollutants, sulfur dioxide (SO 2 ) and nitrogen dioxide (NO 2 ), were sampled and monitored in the spring season in the biggest industrial area of Bhutan. Field measurements of SO 2 and NO 2 were performed using standard colorimetric methods, and air samples were collected using an active sampling technique. Sampling sites were selected to cover all the potential catchment areas like settlements, staff quarters, shops and schools. The main objective of this sampling work was to see the distribution of these two pollutants from the source of emission (small scale industries) and to obtain and establish a baseline data. The active sampler was first tested and validated in a laboratory using liquid and gas standards of SO 2 and NO 2 . Good linearity from 0.050 to 1.0 µg mL -1 for SO 2 and from 0.010 to 1.0 µg mL -1 for NO 2 were obtained (R 2 > 0.99) with limits of detection of 30 and 50 ng mL -1 for SO 2 and NO 2 , respectively. Daylong sampling was done at selected sites with a range of distances away from the sources of emission. The ambient concentration of SO 2 and NO 2 were in the range of 0.45-4.46 and 0.56-5.68 µg m -3 , respectively.

Health risk of inhalation exposure to sub-10 µm particulate matter and gaseous pollutants in an urban-industrial area in South Africa: an ecological study.

PubMed

Morakinyo, Oyewale Mayowa; Adebowale, Ayo Stephen; Mokgobu, Matlou Ingrid; Mukhola, Murembiwa Stanley

2017-03-13

To assess the health risks associated with exposure to particulate matter (PM 10 ), sulphur dioxide (SO 2 ), nitrogen dioxide (NO 2 ), carbon monoxide (CO) and ozone (O 3 ). The study is an ecological study that used the year 2014 hourly ambient pollution data. The study was conducted in an industrial area located in Pretoria West, South Africa. The area accommodates a coal-fired power station, metallurgical industries such as a coke plant and a manganese smelter. Estimate of possible health risks from exposure to airborne PM 10 , SO 2 , NO 2 , CO and O 3 was performed using the US Environmental Protection Agency human health risk assessment framework. A scenario-assessment approach where normal (average exposure) and worst-case (continuous exposure) scenarios were developed for intermediate (24-hour) and chronic (annual) exposure periods for different exposure groups (infants, children, adults). The normal acute (1-hour) exposure to these pollutants was also determined. Presence or absence of adverse health effects from exposure to airborne pollutants. Average annual ambient concentration of PM 10 , NO 2 and SO 2 recorded was 48.3±43.4, 11.50±11.6 and 18.68±25.4 µg/m 3 , respectively, whereas the South African National Ambient Air Quality recommended 40, 40 and 50 µg/m 3 for PM 10 , NO 2 and SO 2 , respectively. Exposure to an hour's concentration of NO 2 , SO 2 , CO and O 3 , an 8-hour concentration of CO and O 3 , and a 24-hour concentration of PM 10 , NO 2 and SO 2 will not likely produce adverse effects to sensitive exposed groups. However, infants and children, rather than adults, are more likely to be affected. Moreover, for chronic annual exposure, PM 10 , NO 2 and SO 2 posed a health risk to sensitive individuals, with the severity of risk varying across exposed groups. Long-term chronic exposure to airborne PM 10 , NO 2 and SO 2 pollutants may result in health risks among the study population. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

[Desulphurization with multi-needle-water film electrodes by corona discharge].

PubMed

Huang, Xu-ran; Li, Guo-feng; Li, Jie; Wu, Yan

2008-09-01

The study of this paper adopted stainless steel multi-needle as a high voltage electrode system, and water film as low voltage electrode. The electrodes were supplied with negative DC high voltage. Polluted gas containing sulfur dioxide (SO2) flowed into the corona discharge field from the center of the high voltage electrode system in an axis direction, then get across the water surface. Under the effect of corona discharge plasma and water absorption, SO2 was removed by converting it into sulfuric acid. The effect of the three factors which were the applied voltage, SO2 inlet concentration and duration of the exposure to the corona discharge on desulphurization efficiency has been studied mostly. Moreover, the concentrations of SO3(2-) and SO4(2-) ions in the water were measured and the mechanism of desulphurization was analyzed. The results showed that there was a synergistic effect on the removal of SO2 when combining corona discharge and water absorption, and both the desulphurization efficiency and the amount of sulfuric acid increased evidently. As the applied voltage and the duration increased, the desulphurization efficiency increased. Also, the SO2 inlet concentration had effect on desulphurization efficiency. When the SO2 inlet concentration was 430 x 10(-6), the voltage was 14.5 kV and the duration was 7.5 s, a desulphurization efficiency of more than 90% could be attained.

Plume Tracker: Interactive mapping of volcanic sulfur dioxide emissions with high-performance radiative transfer modeling

NASA Astrophysics Data System (ADS)

Realmuto, Vincent J.; Berk, Alexander

2016-11-01

We describe the development of Plume Tracker, an interactive toolkit for the analysis of multispectral thermal infrared observations of volcanic plumes and clouds. Plume Tracker is the successor to MAP_SO2, and together these flexible and comprehensive tools have enabled investigators to map sulfur dioxide (SO2) emissions from a number of volcanoes with TIR data from a variety of airborne and satellite instruments. Our objective for the development of Plume Tracker was to improve the computational performance of the retrieval procedures while retaining the accuracy of the retrievals. We have achieved a 300 × improvement in the benchmark performance of the retrieval procedures through the introduction of innovative data binning and signal reconstruction strategies, and improved the accuracy of the retrievals with a new method for evaluating the misfit between model and observed radiance spectra. We evaluated the accuracy of Plume Tracker retrievals with case studies based on MODIS and AIRS data acquired over Sarychev Peak Volcano, and ASTER data acquired over Kilauea and Turrialba Volcanoes. In the Sarychev Peak study, the AIRS-based estimate of total SO2 mass was 40% lower than the MODIS-based estimate. This result was consistent with a 45% reduction in the AIRS-based estimate of plume area relative to the corresponding MODIS-based estimate. In addition, we found that our AIRS-based estimate agreed with an independent estimate, based on a competing retrieval technique, within a margin of ± 20%. In the Kilauea study, the ASTER-based concentration estimates from 21 May 2012 were within ± 50% of concurrent ground-level concentration measurements. In the Turrialba study, the ASTER-based concentration estimates on 21 January 2012 were in exact agreement with SO2 concentrations measured at plume altitude on 1 February 2012.

Measurements of Rural Sulfur Dioxide and Particle Sulfate: Analysis of CASTNet Data, 1987 through 1996.

PubMed

Baumgardner, Ralph E; Isil, Selma S; Bowser, Jon J; Fitzgerald, Kelley M

1999-11-01

The Clean Air Status and Trends Network (CASTNet) was implemented by the U.S. Environmental Protection Agency (EPA) in 1991 in response to Title IX of the Clean Air Amendments of 1990, which mandated the deployment of a national ambient air monitoring network to track progress of the implementation of emission reduction programs in terms of deposition, air quality, and changes to affected ecosystems. CASTNet evolved from the National Dry Deposition Network (NDDN). CASTNet currently consists of 45 sites in the eastern United States and 28 sites in the West. Each site measures sulfur dioxide (SO 2 ), nitric acid (HNO 3 ), particle sulfate (SO 4 = ), particle nitrate (NO 3 - ), and ozone. Nineteen sites collect precipitation samples. NDDN/CASTNet uses a uniform set of site-selection criteria which provides the data user with consistent measures to compare each site. These criteria also ensure that, to the extent possible, CASTNet sites are located away from local emission sources. This paper presents an analysis of SO 2 and SO 4 = concentration data collected from 1987 through 1996 at rural NDDN/CASTNet sites. Annual and seasonal variability is examined. Gradients of SO 2 and SO 4 = are discussed. The variability of the atmospheric mix of SO 2 and SO 4 = is explored spatially and seasonally. Data from CASTNet are also compared to SO 2 and SO 4 = data from concurrent monitoring studies in rural areas.

Broadband UV spectroscopy system used for monitoring of SO 2 and NO emissions from thermal power plants

NASA Astrophysics Data System (ADS)

Zhang, Y. G.; Wang, H. S.; Somesfalean, G.; Wang, Z. Y.; Lou, X. T.; Wu, S. H.; Zhang, Z. G.; Qin, Y. K.

2010-11-01

A gas monitoring system based on broadband absorption spectroscopic techniques in the ultraviolet region is described and tested. The system was employed in real-time continuous concentration measurements of sulfur dioxide (SO 2) and nitric oxide (NO) from a 220-ton h -1 circulating fluidized bed (CFB) boiler in Shandong province, China. The emission coefficients (per kg of coal and per kWh of electricity) and the total emission of the two pollutant gases were evaluated. The measurement results showed that the emission concentrations of SO 2 and NO from the CFB boiler fluctuated in the range of 750-1300 mg m -3 and 100-220 mg m -3, respectively. Compared with the specified emission standards of air pollutants from thermal power plants in China, the values were generally higher for SO 2 and lower for NO. The relatively high emission concentrations of SO 2 were found to mainly depend on the sulfur content of the fuel and the poor desulfurization efficiency. This study indicates that the broadband UV spectroscopy system is suitable for industrial emission monitoring and pollution control.

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

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

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

2010-01-01

With the rapid development of the economy, the sulfur dioxide (SO{sub 2}) emission from China since 2000 is of increasing concern. In this study, we estimate the annual SO{sub 2} emission in China after 2000 using a technology-based methodology specifically for China. From 2000 to 2006, total SO{sub 2} emission in China increased by 53%, from 21.7 Tg to 33.2 Tg, at an annual growth rate of 7.3%. Emissions from power plants are the main sources of SO{sub 2} in China and they increased from 10.6 Tg to 18.6 Tg in the same period. Geographically, emission from north China increasedmore » by 85%, whereas that from the south increased by only 28%. The emission growth rate slowed around 2005, and emissions began to decrease after 2006 mainly due to the wide application of flue-gas desulfurization (FGD) devices in power plants in response to a new policy of China's government. This paper shows that the trend of estimated SO{sub 2} emission in China is consistent with the trends of SO{sub 2} concentration and acid rain pH and frequency in China, as well as with the increasing trends of background SO{sub 2} and sulfate concentration in East Asia. A longitudinal gradient in the percentage change of urban SO{sub 2} concentration in Japan is found during 2000-2007, indicating that the decrease of urban SO{sub 2} is lower in areas close to the Asian continent. This implies that the transport of increasing SO{sub 2} from the Asian continent partially counteracts the local reduction of SO{sub 2} emission downwind. The aerosol optical depth (AOD) products of Moderate Resolution Imaging Spectroradiometer (MODIS) are found to be highly correlated with the surface solar radiation (SSR) measurements in East Asia. Using MODIS AOD data as a surrogate of SSR, we found that China and East Asia excluding Japan underwent a continuous dimming after 2000, which is in line with the dramatic increase in SO{sub 2} emission in East Asia. The trends of AOD from both satellite retrievals and model over East Asia are also consistent with the trend of SO2 emission in China, especially during the second half of the year, when sulfur contributes the largest fraction of AOD. The arrested growth in SO{sub 2} emissions since 2006 is also reflected in the decreasing trends of SO{sub 2} and SO{sub 4}{sup 2-} concentrations, acid rain pH values and frequencies, and AOD over East Asia.« less

Volcanogenic SO2, a natural pollutant: Measurements, modeling and hazard assessment at Vulcano Island (Aeolian Archipelago, Italy).

PubMed

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.

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

NASA Astrophysics Data System (ADS)

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.

Studies of thermochemical water-splitting cycles

NASA Technical Reports Server (NTRS)

Remick, R. J.; Foh, S. E.

1980-01-01

Higher temperatures and more isothermal heat profiles of solar heat sources are developed. The metal oxide metal sulfate class of cycles were suited for solar heat sources. Electrochemical oxidation of SO2 and thermochemical reactions are presented. Electrolytic oxidation of sulfur dioxide in dilute sulfuric acid solutions were appropriate for metal oxide metal sulfate cycles. The cell voltage at workable current densities required for the oxidation of SO2 was critical to the efficient operation of any metal oxide metal sulfate cycle. A sulfur dioxide depolarized electrolysis cell for the splitting of water via optimization of the anode reaction is discussed. Sulfuric acid concentrations of 30 to 35 weight percent are preferred. Platinized platinum or smooth platinum gave the best anode kinetics at a given potential of the five materials examined.

SULFATE PRODUCTION IN CLOUDS IN EASTERN CHINA: OBSERVATIONS FROM MT. TAI

NASA Astrophysics Data System (ADS)

Collett, J. L.; Shen, X.; Lee, T.; Wang, X.; Wang, W.; Wang, T.

2009-12-01

The fate of China’s sulfur dioxide emissions depends, in part, on the ability of regional clouds to support rapid aqueous oxidation of these emissions to sulfate. Sulfur dioxide oxidized in regional clouds is more likely to be removed by wet deposition while sulfur dioxide that undergoes slower gas phase oxidation is expected to survive longer in the atmosphere and exert a radiative forcing impact over a broader spatial scale. Two 2008 field campaigns conducted at Mt. Tai, an isolated peak on the NE China plain, provide insight into the importance of various aqueous phase sulfur oxidation pathways in the region. Single and two-stage cloudwater collectors were used to collect bulk and drop size-resolved samples of cloudwater. Collected cloudwater was analyzed for key species that influence in-cloud sulfate production, including pH, S(IV), H2O2, Fe and Mn. Other major cloud solutes, including inorganic ions, total organic carbon, formaldehyde, and organic acids were also analyzed, as were gas phase concentrations of SO2, O3, and H2O2. A wide range of cloud pH was observed, from below 3 to above 6. High concentrations of cloudwater sulfate were consistent with abundant sulfur dioxide emissions in the region. Despite its fast aqueous reaction with sulfur dioxide, high concentrations of residual hydrogen peroxide were measured in some clouds implying a substantial capacity for additional sulfate production. Ozone was found to be an important S(IV) oxidant in some periods when cloud pH was high. This presentation will examine the importance of different oxidants (H2O2, O3, and O2 catalyzed by trace metals) for sulfur oxidation and the overall capacity of regional clouds to support rapid aqueous phase sulfate production.

Irreversible climate change due to carbon dioxide emissions.

PubMed

Solomon, Susan; Plattner, Gian-Kasper; Knutti, Reto; Friedlingstein, Pierre

2009-02-10

The severity of damaging human-induced climate change depends not only on the magnitude of the change but also on the potential for irreversibility. This paper shows that the climate change that takes place due to increases in carbon dioxide concentration is largely irreversible for 1,000 years after emissions stop. Following cessation of emissions, removal of atmospheric carbon dioxide decreases radiative forcing, but is largely compensated by slower loss of heat to the ocean, so that atmospheric temperatures do not drop significantly for at least 1,000 years. Among illustrative irreversible impacts that should be expected if atmospheric carbon dioxide concentrations increase from current levels near 385 parts per million by volume (ppmv) to a peak of 450-600 ppmv over the coming century are irreversible dry-season rainfall reductions in several regions comparable to those of the "dust bowl" era and inexorable sea level rise. Thermal expansion of the warming ocean provides a conservative lower limit to irreversible global average sea level rise of at least 0.4-1.0 m if 21st century CO(2) concentrations exceed 600 ppmv and 0.6-1.9 m for peak CO(2) concentrations exceeding approximately 1,000 ppmv. Additional contributions from glaciers and ice sheet contributions to future sea level rise are uncertain but may equal or exceed several meters over the next millennium or longer.

Irreversible climate change due to carbon dioxide emissions

PubMed Central

Solomon, Susan; Plattner, Gian-Kasper; Knutti, Reto; Friedlingstein, Pierre

2009-01-01

The severity of damaging human-induced climate change depends not only on the magnitude of the change but also on the potential for irreversibility. This paper shows that the climate change that takes place due to increases in carbon dioxide concentration is largely irreversible for 1,000 years after emissions stop. Following cessation of emissions, removal of atmospheric carbon dioxide decreases radiative forcing, but is largely compensated by slower loss of heat to the ocean, so that atmospheric temperatures do not drop significantly for at least 1,000 years. Among illustrative irreversible impacts that should be expected if atmospheric carbon dioxide concentrations increase from current levels near 385 parts per million by volume (ppmv) to a peak of 450–600 ppmv over the coming century are irreversible dry-season rainfall reductions in several regions comparable to those of the “dust bowl” era and inexorable sea level rise. Thermal expansion of the warming ocean provides a conservative lower limit to irreversible global average sea level rise of at least 0.4–1.0 m if 21st century CO2 concentrations exceed 600 ppmv and 0.6–1.9 m for peak CO2 concentrations exceeding ≈1,000 ppmv. Additional contributions from glaciers and ice sheet contributions to future sea level rise are uncertain but may equal or exceed several meters over the next millennium or longer. PMID:19179281

A 10-year spatial and temporal trend of sulfate across the United States

NASA Astrophysics Data System (ADS)

Malm, William C.; Schichtel, Bret A.; Ames, Rodger B.; Gebhart, Kristi A.

2002-11-01

Legislative and regulatory mandates have resulted in reduced sulfur dioxide (SO2) emissions in both the eastern and western United States with anticipation that concurrent levels of ambient SO2, SO42-, and rainwater acidity would decrease. This paper examines spatial and temporal trends in ambient SO42- concentration from 1988 to 1999, SO2 emissions from 1990 to 1999, and the relationship between these two variables. The SO42- concentration data came from combining data from the Interagency Monitoring of Protected Visual Environments (IMPROVE) and the Clean Air Status and Trends Network (CASTNet). Over 70 sites spread across the continental United States are considered in this analysis. From a spatial perspective, the 90th percentile summer sulfate concentrations are highest along the Ohio River Valley and in central Tennessee where the emission density of SO2 is greatest. These concentrations are a factor of 2 greater than the Northeast, northern Michigan, and coastal areas of the Southeast and about a factor of 15 greater than the central western United States. In the East, the largest SO42- decreases in the 80th percentile concentrations occurred north of the Ohio River Valley, while most monitoring sites south of Kentucky and Virginia showed increasing and decreasing trends that were not statistically significant. Big Bend National Park, Texas, Cranberry, North Carolina, and Lassen Volcanic National Park, California, are the only areas that show a statistically significant increase in SO42- mass concentrations. The 1990-1999 annual 80th percentile SO42- time series were compared to the annual SO2 emissions over four broad United States regions. Each region had a unique time series pattern with the SO42- concentrations and SO2 emissions closely tracking each other over the 10-year period. Both the SO42- and SO2 emissions decreased in the Northeast (28%) and the West (15%), while there was little change in the Southeast and a 15% increase over Texas, New Mexico, and Colorado.

76 FR 49391 - Approval, Disapproval and Promulgation of Air Quality Implementation Plans; Colorado; Smoke...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-08-10

..., Disapproval and Promulgation of Air Quality Implementation Plans; Colorado; Smoke, Opacity and Sulfur Dioxide... opacity, particulate, sulfur dioxide (SO 2 ), and carbon monoxide (CO) emissions from sources. EPA has... mean Nitrogen Dioxide and SO2 mean Sulfur Dioxide. (vii) The initials BACT mean Best Available Control...

75 FR 55713 - Air Quality Implementation Plans; Montana; Attainment Plan for Libby, MT PM2.5

Federal Register 2010, 2011, 2012, 2013, 2014

2010-09-14

... proposing to find on-road directly emitted PM 2.5 and oxides of nitrogen (NO X ) in the Libby, Montana... contribute to fine particle concentrations: direct PM 2.5 , sulfur dioxide (SO 2 ), nitrogen oxides (NO X... balance study (CMB) was conducted during the winter of 2003-2004 by the University of Montana, Center for...

Distribution of Sulfur Dioxide Frost on Io

NASA Technical Reports Server (NTRS)

1997-01-01

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

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

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

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

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

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

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

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

Characterization of SO2 abundance in Venus' night-side mesosphere from SPICAV/VEX observations

NASA Astrophysics Data System (ADS)

Belyaev, Denis; Fedorova, Anna; Piccialli, Arianna; Marcq, Emmanuel; Montmessin, Franck; Bertaux, Jean-Loup; Evdokimova, Daria

Sulfur dioxide (SO _{2}) is a key component of Venus’ atmosphere since the planet is totally covered by H _{2}SO _{4} droplets clouds at altitudes 50-70 km. Any significant change in the SO _{x} oxides above and within the clouds affects the photochemistry in the mesosphere (70-120 km). Recent continuous observations from the Venus Express orbiter (Belyaev et al., 2012; Marcq et al., 2013) and ground-based telescopes (Sandor et al., 2010; Krasnopolsky, 2010; Encrenaz et al., 2012) showed high variability of SO _{2} abundance with years, diurnal time and latitude on the day-side and terminators (commonly from 20 to 500 ppbv above the clouds). In the night-side mesosphere SO _{2} is not photo dissociative but, so far, its behavior has never been explored in details. In this paper we present first results from sulfur dioxide observations made by SPICAV UV spectrometer onboard Venus Express orbiter in regime of stellar occultation (Bertaux et al., 2007). In this mode the instrument observes night-side mesosphere and can register SO _{2} absorption bands in 190-220 nm and CO _{2} bands in 120-200 nm at altitudes from 85 to 110 km (spectral resolution is ˜2 nm). As a result, vertical distribution of SO _{2} and CO _{2} concentrations has been retrieved in observation period from June 2006 to April 2012, at latitude range 60(°) S-60(°) N and Venus local time 20:00-04:00. On the average, mixing ratio of sulfur dioxide fluctuates around ˜100 ppbv along altitude range 90-100 km. Our work is supported by the Program No.22 of RAS and grant of the Russian Government to MIPT. References: Belyaev D. et al., 2012. Vertical profiling of SO _{2} and SO above Venus' clouds by SPICAV/SOIR solar occultations. Icarus 217, 740-751. Bertaux J.-L. et al., 2007. SPICAV on Venus Express: three spectrometers to study the global structure and composition of Venus atmosphere. Planet. Space Sci. 55, 1673-1700. Encrenaz T. et al., 2012. HDO and SO _{2} thermal mapping on Venus: evidence for strong SO _{2} variability. A&A 543, A153. Krasnopolsky V.A., 2010. Spatially-resolved high-resolution spectroscopy of Venus. 2. Variations of HDO, OCS, and SO _{2} at the cloud tops. Icarus 209, 314-322. Marcq E. et al., 2013. Variations of sulphur dioxide at the cloud top of Venus’s dynamic atmosphere. Nature Geoscience, vol. 6, 25-28. DOI: 10.1038/NGEO1650. Sandor B.J. et al., 2010. Sulfur chemistry in the Venus mesosphere from SO _{2} and SO microwave spectra. Icarus 208, 49-60.

Sonochemical reduction of carbon dioxide.

PubMed

Harada, H

1998-06-01

Sonolysis of carbon dioxide dissolved in water was performed from a standpoint of reducing this material in atmosphere. During one hour of sonication, the amount of CO2 decreased to about half at 5 degrees C under CO2-Ar atmosphere. The decreasing rate for CO2 followed the order Ar > He > H2 > N2 and it was down with increasing temperature in the range of 5-45 degrees C. The most favorable concentration for reducing CO2 was 0.03 (mole fraction of CO2 in gas phase). This concentration in gas phase means an equal mixture of CO2 and Ar in water, because CO2 is more soluble than Ar. Since carbon dioxide dissolved in water would be partly ionized, the roles of ions on the sonolysis were also examined. Gaseous reaction products were CO, H2 and a small amount of O2. Carbon monoxide and hydrogen might be obtained from CO2 and H2O by sonolysis, respectively. Both gases are fuel and react each other to C1 compounds such as methanol, and so on. Therefore, irradiation of ultrasonic waves should be an important technique for reducing CO2.

Annual and diurnal variations of gaseous and particulate pollutants in 31 provincial capital cities based on in situ air quality monitoring data from China National Environmental Monitoring Center.

PubMed

Zhao, Suping; Yu, Ye; Yin, Daiying; He, Jianjun; Liu, Na; Qu, Jianjun; Xiao, Jianhua

2016-01-01

Long-term air quality data with high temporal and spatial resolutions are needed to understand some important processes affecting the air quality and corresponding environmental and health effects. The annual and diurnal variations of each criteria pollutant including PM2.5 and PM10 (particulate matter with aerodynamic diameter less than 2.5 μm and 10 μm, respectively), CO (carbon monoxide), NO2 (nitrogen dioxide), SO2 (sulfur dioxide) and O3 (ozone) in 31 provincial capital cities between April 2014 and March 2015 were investigated by cluster analysis to evaluate current air pollution situations in China, and the cities were classified as severely, moderately, and slightly polluted cities according to the variations. The concentrations of air pollutants in winter months were significantly higher than those in other months with the exception of O3, and the cities with the highest CO and SO2 concentrations were located in northern China. The annual variation of PM2.5 concentrations in northern cities was bimodal with comparable peaks in October 2014 and January 2015, while that in southern China was unobvious with slightly high PM2.5 concentrations in winter months. The concentrations of particulate matter and trace gases from primary emissions (SO2 and CO) and NO2 were low in the afternoon (~16:00), while diurnal variation of O3 concentrations was opposite to that of other pollutants with the highest values in the afternoon. The most polluted cities were mainly located in North China Plain, while slightly polluted cities mostly focus on southern China and the cities with high altitude such as Lasa. This study provides a basis for the formulation of future urban air pollution control measures in China. Copyright © 2015 Elsevier Ltd. All rights reserved.

Fractal Analysis of Air Pollutant Concentrations

NASA Astrophysics Data System (ADS)

Cortina-Januchs, M. G.; Barrón-Adame, J. M.; Vega-Corona, A.; Andina, D.

2010-05-01

Air pollution poses significant threats to human health and the environment throughout the developed and developing countries. This work focuses on fractal analysis of pollutant concentration in Salamanca, Mexico. The city of Salamanca has been catalogued as one of the most polluted cities in Mexico. The main causes of pollution in this city are fixed emission sources, such as chemical industry and electricity generation. Sulphur Dioxide (SO2) and Particulate Matter less than 10 micrometer in diameter (PM10) are the most important pollutants in this region. Air pollutant concentrations were investigated by applying the box counting method in time series obtained of the Automatic Environmental Monitoring Network (AEMN). One year of time series of hourly average concentrations were analyzed in order to characterize the temporal structures of SO2 and PM10.

The efficacy of chlorine dioxide in controlling Salmonella contamination and its effect on product quality of chicken broiler carcasses.

PubMed

Thiessen, G P; Usborne, W R; Orr, H L

1984-04-01

A large spin-type chiller in an Ontario poultry processing plant was adapted so that the chill water could be treated with various levels of chlorine dioxide ( ClO2 ), increasing the concentration of ClO2 from 0 to 1.39 mg/liter resulting in reducing the bacteria count to the point where salmonellae could not be isolated from the chill water or the chilled broiler carcasses. In addition, coliform, psychrotroph , and aerobic plate counts were all greatly reduced (less than 1 log cycle) in chill water but were only slightly reduced (less than .5 log cycle) in macerated chicken broiler breast skin. Shelf-life was lengthened for broiler carcasses treated with 1.33 and 1.39 mg/liter ClO2 as compared to control carcasses. Sensory panelists reported no off flavors for any ClO2 concentration but rated broiler skin as being slightly lighter in color compared to control carcasses at all concentrations of ClO2 treatment.

Headspace-Sampling Paper-Based Analytical Device for Colorimetric/Surface-Enhanced Raman Scattering Dual Sensing of Sulfur Dioxide in Wine.

PubMed

Li, Dan; Duan, Huazhen; Ma, Yadan; Deng, Wei

2018-05-01

This study demonstrates a novel strategy for colorimetric/surface-enhanced Raman scattering (SERS) dual-mode sensing of sulfur dioxide (SO 2 ) by coupling headspace sampling (HS) with paper-based analytical device (PAD). The smart and multifunctional PAD is fabricated with a vacuum filtration method in which 4-mercaptopyridine (Mpy)-modified gold nanorods (GNRs)-reduced graphene oxide (rGO) hybrids (rGO/MPy-GNRs), anhydrous methanol, and starch-iodine complex are immobilized into cellulose-based filter papers. The resultant PAD exhibits a deep-blue color with a strong absorption peak at 600 nm due to the formation of an intermolecular charge-transfer complex between starch and iodine. However, the addition of SO 2 induces the Karl Fischer reaction, resulting in the decrease of color and increase of SERS signals. Therefore, the PAD can be used not only as a naked-eye indicator of SO 2 changed from blue to colorless but also as a highly sensitive SERS substrates because of the SO 2 -triggered conversion of Mpy to pyridine methyl sulfate on the GNRs. A distinguishable change in the color was observed at a SO 2 concentration of 5 μM by the naked eye, and a detection limit as low as 1.45 μM was obtained by virtue of UV-vis spectroscopy. The PAD-based SERS method is effective over a wide range of concentrations (1 μM to 2000 μM) for SO 2 , and the detection limit for SO 2 is found to be 1 μM. The HS-PAD based colorimetric/SERS method is applied for the determination of SO 2 in wine, and the detection results match well with those obtained from the traditional Monier-Williams method. This study not only offers a new method for on-site monitoring of SO 2 but also provides a new strategy for designing of paper-based sensing platform for a wide range of field-test applications.

IMPROVED TEMPERATURE STABILITY OF SULFUR DIOXIDE SAMPLES COLLECTED BY THE FEDERAL REFERENCE METHOD

EPA Science Inventory

This report describes an examination of the reagents present in the SO2 Federal Reference Method (FRM) to determine if any change in reagent concentration or condition could bring about substantial, if not complete, retardation of the effect of temperature on the stability of col...

OBSERVATIONS ON THE EFFECT OF PROCESS PARAMETERS ON DIOXIN/FURAN YIELD IN MUNICIPAL WASTE AND COAL SYSTEMS

EPA Science Inventory

Effects of fly ash loading; ash-borne, extractable organics; sulfur dioxide (SO2) and hydrogen chloride concentration; and combustion quality on the formation of polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans (PCDD/Fs) were evaluated in pilot scale tests simu...

Potential Impacts of two SO2 oxidation pathways on regional sulfate concentrations: acqueous-hase oxidation by NO2 and gas-phase oxidation by Stabilized Criegee Intermediates

EPA Science Inventory

We examine the potential impacts of two additional sulfate production pathways using the Community Multiscale Air Quality modeling system. First we evaluate the impact of the aqueous-phase oxidation of S(IV) by nitrogen dioxide using two published rate constants, differing by 1-2...

Development of lysozyme-combined antibacterial system to reduce sulfur dioxide and to stabilize Italian Riesling ice wine during aging process

PubMed Central

Chen, Kai; Han, Shun-yu; Zhang, Bo; Li, Min; Sheng, Wen-jun

2015-01-01

For the purpose of SO2 reduction and stabilizing ice wine, a new antibacterial technique was developed and verified in order to reduce the content of sulfur dioxide (SO2) and simultaneously maintain protein stability during ice wine aging process. Hazardous bacterial strain (lactic acid bacteria, LAB) and protein stability of Italian Riesling ice wine were evaluated in terms of different amounts of lysozyme, SO2, polyphenols, and wine pH by single-factor experiments. Subsequently, a quadratic rotation-orthogonal composite design with four variables was conducted to establish the multiple linear regression model that demonstrated the influence of different treatments on synthesis score between LAB inhibition and protein stability of ice wine. The results showed that, synthesis score can be influenced by lysozyme and SO2 concentrations on an extremely significant level (P < 0.01). Furthermore, the lysozyme-combined antibacterial system, which is specially designed for ice wine aging, was optimized step by step by response surface methodology and ridge analysis. As a result, the optimal proportion should be control in ice wine as follows: 179.31 mg L−1 lysozyme, 177.14 mg L−1 SO2, 0.60 g L−1 polyphenols, and 4.01 ice wine pH. Based on this system, the normalized synthesis score between LAB inhibition and protein stability can reach the highest point 0.920. Finally, by the experiments of verification and comparison, it was indicated that lysozyme-combined antibacterial system, which was a practical and prospective method to reduce SO2 concentration and effectively prevent contamination from hazardous LAB, can be used to stabilize ice wine during aging process. PMID:26405531

Raman spectra and cross sections of ammonia, chlorine, hydrogen sulfide, phosgene, and sulfur dioxide toxic gases in the fingerprint region 400 1400 cm 1

DTIC Science & Technology

2015-11-24

ammonia , chlorine, hydrogen sulfide, phosgene, and sulfur dioxide toxic gases in the fingerprint region 400... ammonia (NH3), chlorine (Cl2), hydrogen sulfide (H2S), phosgene (COCl2), and sulfur dioxide (SO2) toxic gases have been measured in the fingerprint...sections of ammonia (NH3), chlorine (Cl2), hydrogen sulfide (H2S), phosgene (CCl2O), and sulfur dioxide (SO2) toxic gases in the fingerprint

Raman Spectra and Cross Sections of Ammonia, Chlorine, Hydrogen Sulfide, Phosgene, and Sulfur Dioxide Toxic Gases in the Fingerprint Region 400-1400 cm-1

DTIC Science & Technology

2015-12-14

ammonia , chlorine, hydrogen sulfide, phosgene, and sulfur dioxide toxic gases in the fingerprint region 400... ammonia (NH3), chlorine (Cl2), hydrogen sulfide (H2S), phosgene (COCl2), and sulfur dioxide (SO2) toxic gases have been measured in the fingerprint...sections of ammonia (NH3), chlorine (Cl2), hydrogen sulfide (H2S), phosgene (CCl2O), and sulfur dioxide (SO2) toxic gases in the fingerprint region

Indicators for the optical measurement of sulphur dioxide gas

NASA Astrophysics Data System (ADS)

Sharma, Ashutosh; Ali, Zulfiqur; McStay, Daniel

1992-05-01

A number of fluorophores were investigated for their suitability to be employed as indicators in SO2 measurement. Several indicators, including PAll's, 5(and 6) carboxy-4'-5'-dimethyl fluorescein, new fuschin, hydrazine hydrochloride and chioropyridine hydrochloride, showed decrease in the fluorescence intensity with increase in SO2 concentration. Fluorescence quenching of benzopurpurin by 502 is found to be extremely efficient, with a little or no interference from the other toxic gases NH3 and H2S. These results are analyzed using Stem-Volmer relation. The fmding is considered to be of potential utility for the development of an improved fibre optic SO2 sensor/probe.

Ammonia concentrations at a site in Southern Scotland from 2 yr of continuous measurements

NASA Astrophysics Data System (ADS)

Burkhardt, J.; Sutton, M. A.; Milford, C.; Storeton-West, R. L.; Fowler, D.

Atmospheric ammonia (NH 3) concentrations were measured using a continuous-flow annular denuder over a period of 2 yr at a rural site near Edinburgh, Scotland. Meteorological parameters as well as sulphur dioxide (SO 2) concentrations were also recorded. The overall arithmetic mean NH 3 concentration was 1.4 μg m -3. Although an annual cycle with largest NH 3 concentrations in summer was apparent for seasonal geometric mean concentrations, arithmetic mean concentrations were largest in the spring and autumn, indicating the increased importance of occasional high concentration events in these seasons. The NH 3 concentrations were influenced by local sources as well as by background concentrations, dependent on wind direction, whereas SO 2 geometric standard deviations indicated more distant sources. The daily cycle of NH 3 and SO 2 concentrations was dependent on wind speed ( u). At u<1 m s -1, NH 3 concentrations were smallest and SO 2 concentrations were largest around noon, whereas at u>1 m s -1 this cycle was less pronounced for both gases and NH 3 concentrations were largest around 1800 hours. These opposite diurnal cycles may be explained by the interaction of boundary layer mixing with local sources for NH 3 and remote sources for SO 2. Comparing the ammonia data with critical levels and critical loads shows that the critical level is not exceeded at this site over any averaging time. In contrast, the N critical load would probably be exceeded for moorland vegetation near this site, showing that the contribution of atmospheric NH 3 to nitrogen deposition in the long term is a more significant issue than exceedance of critical levels.

Atmospheric dry deposition in the vicinity of the Salton Sea, California - I: Air pollution and deposition in a desert environment

USGS Publications Warehouse

Alonso, R.; Bytnerowicz, A.; Boarman, W.I.

2005-01-01

Air pollutant concentrations and atmospheric dry deposition were monitored seasonally at the Salton Sea, southern California. Measurements of ozone (O 3), nitric acid vapor (HNO3), ammonia (NH3), nitric oxide (NO), nitrogen dioxide (NO2) and sulfur dioxide (SO 2) were performed using passive samplers. Deposition rates of NO 3-, NH4+, Cl-, SO 42-, Na+, K+ and Ca2+ to creosote bush branches and nylon filters as surrogate surfaces were determined for one-week long exposure periods. Maximum O3 values were recorded in spring with 24-h average values of 108.8 ??g m-3. Concentrations of NO and NO2 were low and within ranges of the non-urban areas in California (0.4-5.6 and 3.3-16.2 ??g m-3 ranges, respectively). Concentrations of HNO3 (2.0-6.7 ??g m-3) and NH 3 (6.4-15.7 ??g m-3) were elevated and above the levels typical for remote locations in California. Deposition rates of Cl-, SO42-, Na+, K+ and Ca2+ were related to the influence of sea spray or to suspended soil particles, and no strong enrichments caused by ions originated by human activities were detected. Dry deposition rates of NO3- and NH4+ were similar to values registered in areas where symptoms of nitrogen saturation and changes in species composition have been described. Deposition of nitrogenous compounds might be contributing to eutrophication processes at the Salton Sea. ?? 2005 Elsevier Ltd. All rights reserved.

Growth of radish and marigold following repeated exposure to nitrogen dioxide, sulfur dioxide, and ozone

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

Reinert, R.A.; Sanders, J.S.

Radish and marigold plants were exposed to 0.3 ppm of nitrogen dioxide (NO/sub 2/), sulfur dioxide (SO/sub 2/), and/or ozone (O/sub 3/) nine times during a 3-wk period. No interactions among NO/sub 2/, SO/sub 2/, and O/sub 3/ were detected in measurement of radish foliage and root dry weight. Treatments containing O/sub 3/ reduced radish foliage and root (hypocotyl) dry weight 356 and 531 mg/plant, respectively. Interactions among NO/sub 2/, SO/sub 2/, and O/sub 3/ occurred in shoots and roots of marigold. SO/sub 2/ alone reduced marigold shoot and root dry weight, but this effect was reversed in the presencemore » of O/sub 3/. The suppressive effect of SO/sub 2/ on root weight was also reversed by NO/sub 3/. Treatments containing SO/sub 2/ reduced dry flower weight 0.17 g/plant, but effects of the pollutant interactions observed in shoots and roots were not present.« less

Air quality improvements using European environment policies: a case study of SO2 in a coastal region in Portugal.

PubMed

Pereira, M C; Santos, R C; Alvim-Ferraz, M C M

2007-02-01

The European Union (EU) has defined several efforts for preventing and controlling air pollution that have led to a generalized reduction of health risks and environmental effects. One example of these efforts was the establishment of legislation that imposed a reduction of sulfur content in fuels, switching to cleaner fuels for industry and motor vehicles (Auto-Oil Directives). The goal of this study was to evaluate the first trends in the air quality of Oporto Metropolitan Area (Oporto-MA) related to implementation of these directives in Portugal since 2000. Therefore, sulfur dioxide (SO2) concentration data from air quality monitoring sites were analyzed for the period 1999 through 2003. It was observed that daily SO2 concentrations in the industrial area are much higher than those of the urban and rural areas, reflecting the influence of the industrial sector. The annual SO2 concentrations for the consecutive years of analysis decreased considerably for all the monitoring sites. A considerable decrease in SO2 emissions was also observed for the same period. According to EU legislation, the exceedances of the SO2 recommended limit values decreased significantly. In conclusion, this analysis shows evidence that SO2 concentrations are decreasing, and that this is consistent with the implementation of the legislation and control of the sources of pollution. Nevertheless, the potential for human health risks still persists, particularly in industrialized areas. It is expected that SO2 concentration levels in ambient air of Oporto-MA will continue to decrease in the coming years, following the present European trends.

Measurement of carbon capture efficiency and stored carbon leakage

DOEpatents

Keeling, Ralph F.; Dubey, Manvendra K.

2013-01-29

Data representative of a measured carbon dioxide (CO.sub.2) concentration and of a measured oxygen (O.sub.2) concentration at a measurement location can be used to determine whether the measured carbon dioxide concentration at the measurement location is elevated relative to a baseline carbon dioxide concentration due to escape of carbon dioxide from a source associated with a carbon capture and storage process. Optionally, the data can be used to quantify a carbon dioxide concentration increase at the first location that is attributable to escape of carbon dioxide from the source and to calculate a rate of escape of carbon dioxide from the source by executing a model of gas-phase transport using at least the first carbon dioxide concentration increase. Related systems, methods, and articles of manufacture are also described.

New study on the correlation between carbon dioxide concentration in the environment and radon monitor devices.

PubMed

Shahrokhi, A; Burghele, B D; Fábián, F; Kovács, T

2015-12-01

The influence of high geogenic carbon dioxide concentrations on monitoring devices might present a significant challenge to the measurement of radon concentrations in environments with a high level of carbon dioxide concentration such as volcano sites, mofettes, caves, etc. In this study, the influence of carbon dioxide concentration on several different types of radon monitor devices - including Alpha Spectrometry (Sarad RTM 2200, EQF 3220, RAD7), Ionizing Chamber (AlphaGUARD PQ2000 PRO) and Active Cell (Active scintillation cell, Pylon 300A) - was examined to represent new aspects of radon measuring in environments with carbon dioxide. In light of the results, all measuring devices were exposed to variable conditions affected by carbon dioxide concentration, except for the AlphaGUARD, which was kept in a steady state throughout the experiment. It was observed that alpha spectroscopy devices were affected by carbon dioxide, since measured radon concentrations decreased in the presence of 70% and 90% carbon dioxide concentrations by 26.5 ± 2% and 14.5 ± 2.5% for EQF 3220, and 32 ± 2% and 35.5 ± 2% for RTM 2200. However, the ionizing chamber instrument was unaffected by changes in carbon dioxide concentration. It was determined that the RAD7 performed relatively inefficiently in the presence of carbon dioxide concentrations higher than 67% by an overall efficiency factor of approximately 0.52, confirming that it is not an admissible radon monitor instrument in environments with high carbon dioxide concentrations. Copyright © 2015 Elsevier Ltd. All rights reserved.

Gas Exchange of Algae

PubMed Central

Ammann, Elizabeth C. B.; Lynch, Victoria H.

1967-01-01

The oxygen production of a photosynthetic gas exchanger containing Chlorella pyrenoidosa (1% packed cell volume) was measured when various concentrations of carbon dioxide were present within the culture unit. The internal carbon dioxide concentrations were obtained by manipulating the entrance gas concentration and the flow rate. Carbon dioxide percentages were monitored by means of electrodes placed directly in the nutrient medium. The concentration of carbon dioxide in the nutrient medium which produced maximal photosynthesis was in the range of 1.5 to 2.5% by volume. Results were unaffected by either the level of carbon dioxide in the entrance gas or the rate of gas flow. Entrance gases containing 2% carbon dioxide flowing at 320 ml/min, 3% carbon dioxide at 135 ml/min, and 4% carbon dioxide at 55 ml/min yielded optimal carbon dioxide concentrations in the particular unit studied. By using carbon dioxide electrodes implanted directly in the gas exchanger to optimize the carbon dioxide concentration throughout the culture medium, it should be possible to design more efficient large-scale units. PMID:4382391

Removal of sulfur dioxide and formation of sulfate aerosol in Tokyo

NASA Astrophysics Data System (ADS)

Miyakawa, T.; Takegawa, N.; Kondo, Y.

2007-07-01

Ground-based in situ measurements of sulfur dioxide (SO2) and submicron sulfate aerosol (SO42-) together with carbon monoxide (CO) were conducted at an urban site in Tokyo, Japan from spring 2003 to winter 2004. The observed concentrations of SO2 were affected dominantly by anthropogenic emissions (for example, manufacturing industries) in source areas, while small fraction of the data (<30%) was affected by large point sources of SO2 (power plant and volcano). Although emission sources of CO in Tokyo are different from those of SO2, the major emission sources of CO and SO2 are colocated, indicating that CO can be used as a tracer of anthropogenic SO2 emissions in Tokyo. The ratio of SO42- to total sulfur compounds (SOx = SO2 + SO42-) and the remaining fraction of SOx, which is derived as the ratio of the linear regression slope of the SOx-CO correlation, is used as measures for the formation of SO42- and removal of SOx, respectively. Using these parameters, the average formation efficiency of SO42- (i.e., amount of SO42- produced per SO2 emitted from emission sources) are estimated to be 0.18 and 0.03 in the summer and winter periods, respectively. A simple box model was developed to estimate the lifetime of SOx. The lifetime of SOx for the summer period (26 h) is estimated to be about two times longer than that for the winter period (14 h). The seasonal variations of the remaining fraction of SOx, estimated formation efficiency of SO42-, and lifetime of SOx are likely due to those of the boundary layer height and photochemical activity (i.e., hydroxyl radical). These results provide useful insights into the formation and removal processes of sulfur compounds exported from an urban area.

Enhanced Raman Monitor Project

NASA Technical Reports Server (NTRS)

Westenskow, Dwayne

1996-01-01

Monitoring of gaseous contaminants stems from the need to ensure a healthy and safe environment. NASA/Ames needs sensors that are able to monitor common atmospheric gas concentrations as well as trace amounts of contaminant gases. To provide an accurate assessment of air quality, a monitoring system would need to be continuous and on-line with full spectrum capabilities, allowing simultaneous detection of all gas components in a sample, including both combustible and non-combustible gases. The system demands a high degree of sensitivity to detect low gas concentrations in the low-ppm and sub-ppm regions. For clean and healthy air ('good' category), criteria established by the EPA requires that contaminant concentrations not exceed 4 ppm of carbon monoxide (CO) in an 8 hour period, 60 ppb of ozone(O3) in a one hour period and 30 ppb of sulfur dioxide (SO2) in a 24 hour period. One step below this is the National Ambient Air Quality Standard ('moderate' category) which requires that contaminant concentrations not exceed 9 ppm of carbon monoxide (CO), 120 ppb of ozone (O3) and 140 ppb of sulfur dioxide (SO2) for their respective time periods. Ideally a monitor should be able to detect the concentrations specified in the 'good' category. To benchmark current abilities of Raman technology in gas phase analysis, laboratory experiments were performed to evaluate the RASCAL II anesthetic gas monitor.

SORPTION OF MERCURY SPECIES BY ACTIVATED CARBONS AND CALCIUM-BASES SORBENTS: EFFECT OF TEMPERATURE, MERCURY CONCENTRATION AND ACID GASES

EPA Science Inventory

Bench-scale studies of mercury/sorbent reactions were conducted to understand mechanistic limitations of field-scale attempts to reduce emissions of mercury from combustion processes. The effects of temperature (60 - 140 degrees C), sulfur dioxide (SO2, 1000 ppm ), hydrogen chlor...

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

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

Linn, W.S.; Shamoo, D.A.; Peng, R.C.

Twenty-one volunteers with moderate to severe asthma were exposed to sulfur dioxide (SO{sub 2}) at concentrations of O (control), 0.3, and 0.6 ppm in each of three medication states: (1) low (much of their usual asthma medication withheld), (2) normal (each subject on his own usual medication schedule), and (3) high (usual medication supplemented by inhaled metaproterenol before exposure). Theophylline, the medication usually taken by subjects, was often supplemented by beta-adrenergics. Exposures were for 10 min and were accompanied by continuous heavy exercise (ventilation {approximately} 50 1/min). Lung function and symptoms were measured before and after exposure. With normal medication,more » symptomatic bronchoconstriction occurred with exercise and was exacerbated by 0.6 ppm SO{sub 2}, as reported for mildly unmedicated asthmatics studied previously. Both baseline and post-exposure lung function were noticeably worse in the low-medication state. High medication improved baseline lung function and prevented most broncho-constrictive effect of SO{sup 2}/exercise. High medication also increased heart rate and apparently induced tremor or nervousness in some individuals.« less

Ozone monitoring instrument observations of interannual increases in SO2 emissions from Indian coal-fired power plants during 2005-2012.

PubMed

Lu, Zifeng; Streets, David G; de Foy, Benjamin; Krotkov, Nickolay A

2013-12-17

Due to the rapid growth of electricity demand and the absence of regulations, sulfur dioxide (SO2) emissions from coal-fired power plants in India have increased notably in the past decade. In this study, we present the first interannual comparison of SO2 emissions and the satellite SO2 observations from the Ozone Monitoring Instrument (OMI) for Indian coal-fired power plants during the OMI era of 2005-2012. A detailed unit-based inventory is developed for the Indian coal-fired power sector, and results show that its SO2 emissions increased dramatically by 71% during 2005-2012. Using the oversampling technique, yearly high-resolution OMI maps for the whole domain of India are created, and they reveal a continuous increase in SO2 columns over India. Power plant regions with annual SO2 emissions greater than 50 Gg year(-1) produce statistically significant OMI signals, and a high correlation (R = 0.93) is found between SO2 emissions and OMI-observed SO2 burdens. Contrary to the decreasing trend of national mean SO2 concentrations reported by the Indian Government, both the total OMI-observed SO2 and annual average SO2 concentrations in coal-fired power plant regions increased by >60% during 2005-2012, implying the air quality monitoring network needs to be optimized to reflect the true SO2 situation in India.

Growth of radish and marigold following repeated exposure to nitrogen dioxide, sulfur dioxide, and ozone

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

Reinert, R.A.; Sanders, J.S.

Radish and marigold plants were exposed to 0.3 ppM of nitrogen dioxide (NO/sub 2/), sulfur dioxide (SO/sub 2/), and /or ozone (O/sub 3/) nine times during a 3-wk period. No interactions among NO/sub 2/, SO/sub 2/, and O/sub 3/ were detected in measurement of radish foliage and root dry weight. Treatments containing O/sub 3/ reduced radish foliage and root (hypocotyl) dry weight 356 and 531 mg/plant, respectively. Interactions among NO/sub 2/, SO/sub 2/ and O/sub 3/ occurred in shoots and roots of marigold. SO/sub 2/ alone reduced marigold shoot and root dry weight, but this effect was reversed in themore » presence of O/sub 3/. The suppressive effect of SO/sub 2/ on root weight was also reversed by NO/sub 2/. Treatments containing SO/sub 2/ reduced dry flower weight 0.17 g/plant, but effects of the pollutant interactions observed in shoots and roots were not present. 8 references, 2 tables.« less

A computerized system to measure and predict air quality for emission control

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

Crooks, G.; Ciccone, A.; Frattolillo, P.

1997-12-31

A Supplementary Emission Control (SEC) system has been developed on behalf of the Association Industrielle de l`Est de Montreal (AIEM). The objective of the SEC is to avoid exceedences of the Montreal Urban Community (MUC) 24 hour ambient Air Quality Standard (AQS) for sulphur dioxide in the industrial East Montreal area. The SEC system is comprised of: 3 continuous SO{sub 2} monitoring stations with data loggers and remote communications; a meteorological tower with data logger and modem for acquiring local meteorology; communications with Environment Canada to download meteorological forecast data; a polling PC for data retrieval; and Windows NT basedmore » software running on the AIEM computer server. The SEC software utilizes relational databases to store and maintain measured SO{sub 2} concentration data, emission data, as well as observed and forecast meteorological data. The SEC system automatically executes a numerical dispersion model to forecast SO{sub 2} concentrations up to six hours in the future. Based on measured SO{sub 2} concentrations at the monitoring stations and the six hour forecast concentrations, the system determines if local sources should reduce their emission levels to avoid potential exceedences of the AQS. The SEC system also includes a Graphical User Interface (GUI) for user access to the system. The SEC system and software are described, and the accuracy of the system at forecasting SO{sub 2} concentrations is examined.« less

Novel Process of Simultaneous Removal of Nitric Oxide and Sulfur Dioxide Using a Vacuum Ultraviolet (VUV)-Activated O2/H2O/H2O2 System in A Wet VUV-Spraying Reactor.

PubMed

Liu, Yangxian; Wang, Qian; Pan, Jianfeng

2016-12-06

A novel process for NO and SO 2 simultaneous removal using a vacuum ultraviolet (VUV, with 185 nm wavelength)-activated O 2 /H 2 O/H 2 O 2 system in a wet VUV-spraying reactor was developed. The influence of different process variables on NO and SO 2 removal was evaluated. Active species (O 3 and ·OH) and liquid products (SO 3 2- , NO 2 - , SO 4 2- , and NO 3 - ) were analyzed. The chemistry and routes of NO and SO 2 removal were investigated. The oxidation removal system exhibits excellent simultaneous removal capacity for NO and SO 2 , and a maximum removal of 96.8% for NO and complete SO 2 removal were obtained under optimized conditions. SO 2 reaches 100% removal efficiency under most of test conditions. NO removal is obviously affected by several process variables. Increasing VUV power, H 2 O 2 concentration, solution pH, liquid-to-gas ratio, and O 2 concentration greatly enhances NO removal. Increasing NO and SO 2 concentration obviously reduces NO removal. Temperature has a dual impact on NO removal, which has an optimal temperature of 318 K. Sulfuric acid and nitric acid are the main removal products of NO and SO 2 . NO removals by oxidation of O 3 , O·, and ·OH are the primary routes. NO removals by H 2 O 2 oxidation and VUV photolysis are the complementary routes. A potential scaled-up removal process was also proposed initially.

Removal of hazardous gaseous pollutants from industrial flue gases by a novel multi-stage fluidized bed desulfurizer.

PubMed

Mohanty, C R; Adapala, Sivaji; Meikap, B C

2009-06-15

Sulfur dioxide and other sulfur compounds are generated as primary pollutants from the major industries such as sulfuric acid plants, cupper smelters, catalytic cracking units, etc. and cause acid rain. To remove the SO(2) from waste flue gas a three-stage counter-current multi-stage fluidized bed adsorber was developed as desulfurization equipment and operated in continuous bubbling fluidization regime for the two-phase system. This paper represents the desulfurization of gas mixtures by chemical sorption of sulfur dioxide on porous granular calcium oxide particles in the reactor at ambient temperature. The advantages of the multi-stage fluidized bed reactor are of high mass transfer and high gas-solid residence time that can enhance the removal of acid gas at low temperature by dry method. Experiments were carried out in the bubbling fluidization regime supported by visual observation. The effects of the operating parameters such as sorbent (lime) flow rate, superficial gas velocity, and the weir height on SO(2) removal efficiency in the multistage fluidized bed are reported. The results have indicated that the removal efficiency of the sulfur dioxide was found to be 65% at high solid flow rate (2.0 kg/h) corresponding to lower gas velocity (0.265 m/s), wier height of 70 mm and SO(2) concentration of 500 ppm at room temperature.

The future of airborne sulfur-containing particles in the absence of fossil fuel sulfur dioxide emissions

DOE PAGES

Perraud, Véronique; Horne, Jeremy R.; Martinez, Andrew S.; ...

2015-10-19

Sulfuric acid (H2SO4), formed from oxidation of sulfur dioxide (SO2) emitted during fossil fuel combustion, is a major precursor of new airborne particles, which have well-documented detrimental effects on health, air quality, and climate. Another precursor is methanesulfonic acid (MSA), produced simultaneously with SO2 during the atmospheric oxidation of organosulfur compounds (OSCs), such as dimethyl sulfide. In the present paper, a multidisciplinary approach is used to examine how contributions of H2SO4 and MSA to particle formation will change in a large coastal urban area as anthropogenic fossil fuel emissions of SO2 decline. The 3-dimensional University of California Irvine–California Institute ofmore » Technology airshed model is used to compare atmospheric concentrations of gas phase MSA, H2SO4, and SO2 under current emissions of fossil fuel-associated SO2 and a best-case futuristic scenario with zero fossil fuel sulfur emissions. Model additions include results from (i) quantum chemical calculations that clarify the previously uncertain gas phase mechanism of formation of MSA and (ii) a combination of published and experimental estimates of OSC emissions, such as those from marine, agricultural, and urban processes, which include pet waste and human breath. Results show that in the zero anthropogenic SO2 emissions case, particle formation potential from H2SO4 will drop by about two orders of magnitude compared with the current situation. However, particles will continue to be generated from the oxidation of natural and anthropogenic sources of OSCs, with contributions from MSA and H2SO4 of a similar order of magnitude. Finally, this could be particularly important in agricultural areas where there are significant sources of OSCs.« less

The future of airborne sulfur-containing particles in the absence of fossil fuel sulfur dioxide emissions.

PubMed

Perraud, Véronique; Horne, Jeremy R; Martinez, Andrew S; Kalinowski, Jaroslaw; Meinardi, Simone; Dawson, Matthew L; Wingen, Lisa M; Dabdub, Donald; Blake, Donald R; Gerber, R Benny; Finlayson-Pitts, Barbara J

2015-11-03

Sulfuric acid (H2SO4), formed from oxidation of sulfur dioxide (SO2) emitted during fossil fuel combustion, is a major precursor of new airborne particles, which have well-documented detrimental effects on health, air quality, and climate. Another precursor is methanesulfonic acid (MSA), produced simultaneously with SO2 during the atmospheric oxidation of organosulfur compounds (OSCs), such as dimethyl sulfide. In the present work, a multidisciplinary approach is used to examine how contributions of H2SO4 and MSA to particle formation will change in a large coastal urban area as anthropogenic fossil fuel emissions of SO2 decline. The 3-dimensional University of California Irvine-California Institute of Technology airshed model is used to compare atmospheric concentrations of gas phase MSA, H2SO4, and SO2 under current emissions of fossil fuel-associated SO2 and a best-case futuristic scenario with zero fossil fuel sulfur emissions. Model additions include results from (i) quantum chemical calculations that clarify the previously uncertain gas phase mechanism of formation of MSA and (ii) a combination of published and experimental estimates of OSC emissions, such as those from marine, agricultural, and urban processes, which include pet waste and human breath. Results show that in the zero anthropogenic SO2 emissions case, particle formation potential from H2SO4 will drop by about two orders of magnitude compared with the current situation. However, particles will continue to be generated from the oxidation of natural and anthropogenic sources of OSCs, with contributions from MSA and H2SO4 of a similar order of magnitude. This could be particularly important in agricultural areas where there are significant sources of OSCs.

The future of airborne sulfur-containing particles in the absence of fossil fuel sulfur dioxide emissions

PubMed Central

Perraud, Véronique; Horne, Jeremy R.; Martinez, Andrew S.; Kalinowski, Jaroslaw; Meinardi, Simone; Dawson, Matthew L.; Wingen, Lisa M.; Dabdub, Donald; Blake, Donald R.; Gerber, R. Benny; Finlayson-Pitts, Barbara J.

2015-01-01

Sulfuric acid (H2SO4), formed from oxidation of sulfur dioxide (SO2) emitted during fossil fuel combustion, is a major precursor of new airborne particles, which have well-documented detrimental effects on health, air quality, and climate. Another precursor is methanesulfonic acid (MSA), produced simultaneously with SO2 during the atmospheric oxidation of organosulfur compounds (OSCs), such as dimethyl sulfide. In the present work, a multidisciplinary approach is used to examine how contributions of H2SO4 and MSA to particle formation will change in a large coastal urban area as anthropogenic fossil fuel emissions of SO2 decline. The 3-dimensional University of California Irvine–California Institute of Technology airshed model is used to compare atmospheric concentrations of gas phase MSA, H2SO4, and SO2 under current emissions of fossil fuel-associated SO2 and a best-case futuristic scenario with zero fossil fuel sulfur emissions. Model additions include results from (i) quantum chemical calculations that clarify the previously uncertain gas phase mechanism of formation of MSA and (ii) a combination of published and experimental estimates of OSC emissions, such as those from marine, agricultural, and urban processes, which include pet waste and human breath. Results show that in the zero anthropogenic SO2 emissions case, particle formation potential from H2SO4 will drop by about two orders of magnitude compared with the current situation. However, particles will continue to be generated from the oxidation of natural and anthropogenic sources of OSCs, with contributions from MSA and H2SO4 of a similar order of magnitude. This could be particularly important in agricultural areas where there are significant sources of OSCs. PMID:26483454

The future of airborne sulfur-containing particles in the absence of fossil fuel sulfur dioxide emissions

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

Perraud, Véronique; Horne, Jeremy R.; Martinez, Andrew S.

Sulfuric acid (H2SO4), formed from oxidation of sulfur dioxide (SO2) emitted during fossil fuel combustion, is a major precursor of new airborne particles, which have well-documented detrimental effects on health, air quality, and climate. Another precursor is methanesulfonic acid (MSA), produced simultaneously with SO2 during the atmospheric oxidation of organosulfur compounds (OSCs), such as dimethyl sulfide. In the present paper, a multidisciplinary approach is used to examine how contributions of H2SO4 and MSA to particle formation will change in a large coastal urban area as anthropogenic fossil fuel emissions of SO2 decline. The 3-dimensional University of California Irvine–California Institute ofmore » Technology airshed model is used to compare atmospheric concentrations of gas phase MSA, H2SO4, and SO2 under current emissions of fossil fuel-associated SO2 and a best-case futuristic scenario with zero fossil fuel sulfur emissions. Model additions include results from (i) quantum chemical calculations that clarify the previously uncertain gas phase mechanism of formation of MSA and (ii) a combination of published and experimental estimates of OSC emissions, such as those from marine, agricultural, and urban processes, which include pet waste and human breath. Results show that in the zero anthropogenic SO2 emissions case, particle formation potential from H2SO4 will drop by about two orders of magnitude compared with the current situation. However, particles will continue to be generated from the oxidation of natural and anthropogenic sources of OSCs, with contributions from MSA and H2SO4 of a similar order of magnitude. Finally, this could be particularly important in agricultural areas where there are significant sources of OSCs.« less

Annual soil CO_{2} production in Moscow Botanical Garden (Russia).

NASA Astrophysics Data System (ADS)

Udovenko, Maria; Goncharova, Olga; Matyshak, Georgy

2017-04-01

Soil respiration is an essential component of the carbon cycle, determining 25-40 % of carbon dioxide in the atmosphere. Urban soils are subject to significant anthropogenic influences. Anthropogenic impact affects both the plants and the soil microbiota. So, soil CO2 efflux and soil profile CO2 concentration probably differ in urban and natural soils. Influence of abiotic factors on soil carbon dioxide production is explored insufficiently. The research of their impact on soil carbon dioxide production is necessary to predict soil response to anthropogenic climate change. The aim of this study was estimation of annual soil CO2 production and the impact of climatic factors on it. The research took place in Moscow State University Botanical Garden Arboretum (southern taiga). Investigations were carried out at two sites: the areas planted with Picea obovata and Carpinus betulus. The study was conducted with 1-2 weeks intervals between November 2014 and December 2015. Emission measurement were carried out by closed chamber technique, profile concentration were measured by soil air sampling tubes method. Annual carbon dioxide soil surface efflux of soil planted with Picea obovata was 1370 gCO2/(m2 * year), soil planted with Carpinus betulus - 1590 gCO2/(m2 * year). Soil CO2 concentration increased with depth in average of 3300 to 12000 ppm (at 80 cm depth). Maximum concentration values are confined to the end of vegetation period (high biological activity) and to beginning of spring (spring ice cover of soil prevents CO2 emission). Soil CO2 efflux depends on soil temperature at 10 cm depth (R = 0.89; p <0.05), in a less degree it correlate with soil surface temperature and with soil temperature at 20 cm depth (r=0.88; p<0.05). Soil moisture has a little effect on CO2 efflux in the annual cycle (r=-0.16; p<0.05). However in vegetation period efflux of carbon dioxide largely depends on soil moisture, due to the fact, that soil moisture is limiting factor for soil microbiota activity and plant respiration.

Gaseous and aerosol pollutants during fog and clear episodes in South Asian urban atmosphere

NASA Astrophysics Data System (ADS)

Biswas, K. F.; Ghauri, Badar M.; Husain, Liaquat

We report the first measurements of acidic gases and ammonia (NH 3) during fog and clear episodes in Lahore, a highly polluted mega-city of South Asia, along with concentrations of PM 2.5 (particles of <2.5 μm aerodynamic diameter) and ions. An annular denuder system was used to measure acidic gases, NH 3, and PM 2.5 from December 2005 to February 2006 in Lahore, a mega-city in Pakistan. The denuders yielded average concentrations (μg m -3) as follows: ammonia, 50; nitrous acid, 19.6; sulfur dioxide, 19.4; hydrochloric acid, 1.16; nitric acid, 1.00; and oxalic acid, 0.6. The filters yielded average concentrations (μg m -3): PM 2.5, 209; sulfate, 19.2; nitrate, 18.9; chloride, 7.43; oxalate, 0.97; ammonium, 16.1; potassium, 3.49; calcium, 0.89; sodium, 0.76; and magnesium, 0.08. Emissions from local sources, e.g., fossil fuel consumption by motorized transport and power plants, farming, burning of agricultural residues, industrial and construction activities contributed the major proportion of pollutants in Lahore. Concentrations of ionic species, e.g., NO 3-, SO 42-, Na +, NH 4+, Mg 2+, and Ca 2+, and gaseous species, e.g., HCl, HNO 3, SO 2 and (COOH) 2 showed a distinct diurnal variation. Mixing heights and photochemistry played major roles in defining the diurnal pattern. Fog appeared to profoundly enhance the oxidation of sulfur dioxide. High moisture content of fog resulted in uptake of the gases in fog droplets.

Longitudinal study of children exposed to sulfur oxides

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

Dodge, R.; Solomon, P.; Moyers, J.

1985-05-01

This study is a longitudinal comparison of the health of children exposed to markedly different concentrations of sulfur dioxide and moderately different concentrations of particulate sulfate. The four groups of subjects lived in two areas of one smelter town and in two other towns, one of which was also a smelter town. In the area of highest pollution, children were intermittently exposed to high SO/sub 2/ levels (peak three-hour average concentration exceeded 2,500 micrograms/m3) and moderate particulate SO/sub 4/= levels (average concentration was 10.1 micrograms/m3). When the children were grouped by the four gradients of pollution observed, the prevalence ofmore » cough (measured by questionnaire) correlated significantly with pollution levels (trend chi-square = 5.6, p = 0.02). No significant differences in the incidence of cough or other symptoms occurred among the groups of subjects over three years, and pulmonary function and lung function growth over the study were roughly equal among all the groups. These results suggest that intermittent elevations in SO/sub 2/ concentration, in the presence of moderate particulate SO/sub 4/= concentration, produced evidence of bronchial irritation in the subjects, but no chronic effect on lung function or lung function growth was detected.« less

An evaluation of ambient sulphur dioxide concentrations from passive degassing of the Sulphur Springs, Saint Lucia geothermal system: Implications for human health

NASA Astrophysics Data System (ADS)

Joseph, Erouscilla P.; Beckles, Denise M.; Cox, Leonette; Jackson, Viveka B.; Alexander, Dominic

2015-10-01

Sulphur Springs Park in Saint Lucia is a site of energetic geothermal activity associated with the potentially active Soufrière Volcanic Centre. The Park is one of Saint Lucia's most important tourist attractions, and is marketed as the 'world's only drive-in volcano'. It has an on-site staff of tour guides and vendors, as well as over 200,000 visitors annually. There are also a number of residents living in the areas bordering the Park. Recreational use is made of the geothermal waters for bathing, application of mud masques, and in some cases drinking. As part of the University of the West Indies, Seismic Research Centre's (UWI-SRC's) overall volcano monitoring programme for Saint Lucia, the volcanic emissions at Sulphur Springs (hot springs, mud pools and fumaroles) have been regularly monitored since 2001. In recent years, visitors, staff, and management at the Park have expressed concern about the health effects of exposure to volcanic emissions from the hydrothermal system. In response to this, SRC has expanded its regular geothermal monitoring programme to include a preliminary evaluation of ambient sulphur dioxide (SO2) concentrations in and around the Park, to assess the possible implications for human health. Passive diffusion tubes were used to measure the atmospheric SO2 concentrations at various sites in Sulphur Springs Park (SSP), in the town of Soufrière and in the capital of Castries. Measurements of average monthly ambient SO2 with the passive samplers indicated that during the dry season period of April to July 2014 concentration at sites closest to the main vents at SSP (Group 1), which are routinely used by staff and visitors, frequently exceeded the WHO 10-minute AQG for SO2 of 500 μg/m3. However, for sites that were more distal to the main venting area (Groups 2 and 3), the average monthly ambient SO2 did not exceed the WHO 10-minute AQG for SO2 of 500 μg/m3 during the entire monitoring period. The measured concentrations and dispersion patterns of ambient SO2 at SSP appear to be influenced by rainfall, proximity to the fumarolic vents, altitude (local topography), local atmospheric circulation and plume dispersion, and anthropogenic sources. Brochures and posters were prepared, for public distribution and display, on possible gas hazards that may be encountered at SSP and precautionary measures that may be taken by visitors to help minimise potential risk from elevated exposure to volcanic gases.

Estimated long-term outdoor air pollution concentrations in a cohort study

NASA Astrophysics Data System (ADS)

Beelen, Rob; Hoek, Gerard; Fischer, Paul; Brandt, Piet A. van den; Brunekreef, Bert

Several recent studies associated long-term exposure to air pollution with increased mortality. An ongoing cohort study, the Netherlands Cohort Study on Diet and Cancer (NLCS), was used to study the association between long-term exposure to traffic-related air pollution and mortality. Following on a previous exposure assessment study in the NLCS, we improved the exposure assessment methods. Long-term exposure to nitrogen dioxide (NO 2), nitrogen oxide (NO), black smoke (BS), and sulphur dioxide (SO 2) was estimated. Exposure at each home address ( N=21 868) was considered as a function of a regional, an urban and a local component. The regional component was estimated using inverse distance weighed interpolation of measurement data from regional background sites in a national monitoring network. Regression models with urban concentrations as dependent variables, and number of inhabitants in different buffers and land use variables, derived with a Geographic Information System (GIS), as predictor variables were used to estimate the urban component. The local component was assessed using a GIS and a digital road network with linked traffic intensities. Traffic intensity on the nearest road and on the nearest major road, and the sum of traffic intensity in a buffer of 100 m around each home address were assessed. Further, a quantitative estimate of the local component was estimated. The regression models to estimate the urban component explained 67%, 46%, 49% and 35% of the variances of NO 2, NO, BS, and SO 2 concentrations, respectively. Overall regression models which incorporated the regional, urban and local component explained 84%, 44%, 59% and 56% of the variability in concentrations for NO 2, NO, BS and SO 2, respectively. We were able to develop an exposure assessment model using GIS methods and traffic intensities that explained a large part of the variations in outdoor air pollution concentrations.

Separation of sulfur isotopes

DOEpatents

DeWitt, Robert; Jepson, Bernhart E.; Schwind, Roger A.

1976-06-22

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

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

USGS Publications Warehouse

Wallace, P.J.; Gerlach, T.M.

1994-01-01

Sulfur dioxide (SO2) released by the explosive eruption of Mount Pinatubo on 15 June 1991 had an impact on climate and stratospheric ozone. The total mass of SO2 released was much greater than the amount dissolved in the magma before the eruption, and thus an additional source for the excess SO2 is required. Infrared spectroscopic analyses of dissolved water and carbon dioxide in glass inclusions from quartz phenocrysts demonstrate that before eruption the magma contained a separate, SO2-bearing vapor phase. Data for gas emissions from other volcanoes in subduction-related arcs suggest that preeruptive magmatic vapor is a major source of the SO2 that is released during many volcanic eruptions.

40 CFR Appendix D to Part 52 - Determination of Sulfur Dioxide Emissions From Stationary Sources by Continuous Monitors

Code of Federal Regulations, 2011 CFR

2011-07-01

... Emissions From Stationary Sources by Continuous Monitors D Appendix D to Part 52 Protection of Environment... equipment required for the continuous determination of SO2 gas concentration in a given source effluent. 1... Drift. The change in measurement system output over a stated period of time of normal continuous...

The spatial-temporal distribution of the atmospheric polluting agents during the period 2000-2005 in the Urban Area of Guadalajara, Jalisco, Mexico.

PubMed

Sánchez, Hermes U Ramírez; García, María D Andrade; Bejaran, Rubén; Guadalupe, Mario E García; Vázquez, Antonio Wallo; Toledano, Ana C Pompa; Villasenor, Odila de la Torre

2009-06-15

In the large cities, the disordered urban development, the industrial activities, and the transport, have caused elevated concentrations of polluting agents and possible risks to the health of the population. The metropolises located in valleys with little ventilation (such as the Urban Area of Guadalajara: UAG) present low dispersion of polluting agents can cause high risk of respiratory and cardiovascular diseases. The objective of this work was to describe the spatial-temporal distribution of the atmospheric polluting agents: carbon monoxide (CO), nitrogen dioxide (NO(2)), sulfur dioxide (SO(2)), particles smaller than 10 microns (microm) (PM(10)) and ozone (O(3)) in the UAG during the period 2000-2005. A spatial-temporal distribution analysis was made by means of graphic interpolation (Kriging method) of the statistical parameters of CO, NO(2), SO(2), PM(10) and O(3) with the collected data from eight stations of atmospheric monitoring in the UAG. The results show that the distributions of the atmospheric polluting agents are variable during the analyzed years. The polluting agent with highest concentration is PM(10) (265.42 microg/m(3)), followed by O(3) (0.11 ppm), NO(2) (0.11 ppm), CO (9.17 ppm) and SO(2) (0.05 ppm). The most affected zone is the southeast of the UAG. The results showed that an important percentage of days exceed the Mexican norms of air quality (93-199 days/year).

Method of detecting sulfur dioxide

DOEpatents

Spicer, Leonard D.; Bennett, Dennis W.; Davis, Jon F.

1985-01-01

(CH.sub.3).sub.3 SiNSO is produced by the reaction of ((CH.sub.3).sub.3 Si).sub.2 NH with SO.sub.2. Also produced in the reaction are ((CH.sub.3).sub.3 Si).sub.2 O and a new solid compound [NH.sub.4 ][(CH.sub.3).sub.3 SiOSO.sub.2 ]. Both (CH.sub.3).sub.3 SiNSO and [NH.sub.4 ][(CH.sub.3).sub.3 SiOSO.sub.2 ] have fluorescent properties. The reaction of the subject invention is used in a method of measuring the concentration of SO.sub.2 pollutants in gases. By the method, a sample of gas is bubbled through a solution of ((CH.sub.3).sub.3 Si).sub.2 NH, whereby any SO.sub.2 present in the gas will react to produce the two fluorescent products. The measured fluorescence of these products can then be used to calculate the concentration of SO.sub.2 in the original gas sample. The solid product [NH.sub.4][(CH.sub.3).sub.3 SiOSO.sub.2 ] may be used as a standard in solid state NMR spectroscopy.

NASA Carbon Sleuth Begins Year Two

NASA Image and Video Library

2015-10-29

Global average carbon dioxide concentrations as seen by NASA’s Orbiting Carbon Observatory-2 mission, June 1-15, 2015. OCO-2 measures carbon dioxide from the top of Earth's atmosphere to its surface. Higher carbon dioxide concentrations are in red, with lower concentrations in yellows and greens. Scientists poring over data from OCO-2 mission are seeing patterns emerge as they seek answers to questions about atmospheric carbon dioxide. Among the most striking features visible in the first year of OCO-2 data is the increase in carbon dioxide in the northern hemisphere during winter, when trees are not removing carbon dioxide, followed by its decrease in spring, as trees start to grow and remove carbon dioxide from the atmosphere. http://photojournal.jpl.nasa.gov/catalog/PIA20039

Detection of forest decline in Monchegorsk area

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

Hagner, O.; Rigina, O.

1998-01-01

Forests on the Kola Peninsula in Northern Russia are growing close to the limits of the northern tree line. They are subjected to both natural (low temperatures and a short period of biochemical activity) and anthropogenic stress factors. The metallurgic industry complex Severo-nickel close to the city of Monchegorsk in the central Russian Kola Peninsula is one of the major sources of sulfur dioxide (SO{sub 2}), nickel, and copper emissions in the region. The environmental impact on the surrounding area is dramatic. In this study multispectral changes observed in Landsat-MSS satellite image data from 1978, 1986, and 1992 are usedmore » to evaluate the relevance of a mathematical model of SO{sub 2} concentration in ambient air as a component for assessment of forest decline. The multispectral changes detected were found to have a statistically significant correspondence to the modeled (SO{sub 2}) concentration levels in ambient air.« less

Cloud chemistry in eastern China: Observations from Mt. Tai

NASA Astrophysics Data System (ADS)

Collett, J. L.; Shen, X.; Lee, T.; Wang, X.; Li, Y.; Wang, W.; Wang, T.

2010-07-01

Until recently, studies of fog and cloud chemistry in China have been rare - even though the fate of China’s large sulfur dioxide emissions depends, in part, on the ability of regional clouds to support rapid aqueous oxidation to sulfate. Sulfur dioxide oxidized in regional clouds is more likely to be removed by wet deposition while sulfur dioxide that undergoes slower gas phase oxidation is expected to survive longer in the atmosphere and be transported over a much broader spatial scale. Two 2008 field campaigns conducted at Mt. Tai, an isolated peak on the NE China plain, provide insight into the chemical composition of regional clouds and the importance of various aqueous phase sulfur oxidation pathways. Single and two-stage Caltech Active Strand Cloudwater Collectors were used to collect bulk and drop size-resolved samples of cloudwater. Collected cloudwater was analyzed for key species that influence in-cloud sulfate production, including pH, S(IV), H2O2, Fe and Mn. Other major cloud solutes, including inorganic ions, total organic carbon (TOC), formaldehyde, and organic acids were also analyzed, as were gas phase concentrations of SO2, O3, and H2O2. A wide range of cloud pH was observed, from below 3 to above 6. High concentrations of cloudwater sulfate were consistent with abundant sulfur dioxide emissions in the region. Sampled clouds were also found to contain high concentrations of ammonium, nitrate, and organic carbon. Peak TOC concentrations reached approximately 200 ppmC, among the highest concentrations ever measured in cloudwater. Hydrogen peroxide was found to be the dominant aqueous phase S(IV) oxidant when cloud pH was less than approximately 5.4. Despite its fast reaction with sulfur dioxide in cloud droplets, high concentrations of residual hydrogen peroxide were measured in some clouds implying a substantial additional capacity for sulfate production. Ozone was found to be an important S(IV) oxidant when cloud pH was high. Oxidation of S(IV) by oxygen, catalyzed by Fe (III) and Mn(II) was generally the second or third fastest pathway for sulfate production. Differences between the pH and trace metal concentrations of small and large cloud droplets were observed, giving rise to aqueous phase sulfate production rates that were drop size-dependent for the ozone and metal-catalyzed pathways.

42 CFR Appendix - Tables to Subpart L of Part 84

Code of Federal Regulations, 2010 CFR

2010-10-01

... respiratory protection against more than one gas of a type, as for use in chlorine and sulfur dioxide, the... Ammonia Equilibrated NH3 1000 32 4 50 50 Chlorine As received Cl2 500 64 3 5 35 Chlorine Equilibrated Cl2... Sulfur dioxide As received SO2 500 64 3 5 30 Sulfur dioxide Equilibrated SO2 500 32 4 5 30 1 Minimum life...

Simultaneous removal of nitrogen oxide/nitrogen dioxide/sulfur dioxide from gas streams by combined plasma scrubbing technology.

PubMed

Chang, Moo Been; Lee, How Ming; Wu, Feeling; Lai, Chi Ren

2004-08-01

Oxides of nitrogen (NOx) [nitrogen oxide (NO) + nitrogen dioxide (NO2)] and sulfur dioxide (SO2) are removed individually in traditional air pollution control technologies. This study proposes a combined plasma scrubbing (CPS) system for simultaneous removal of SO2 and NOx. CPS consists of a dielectric barrier discharge (DBD) and wet scrubbing in series. DBD is used to generate nonthermal plasmas for converting NO to NO2. The water-soluble NO2 then can be removed by wet scrubbing accompanied with SO2 removal. In this work, CPS was tested with simulated exhausts in the laboratory and with diesel-generator exhausts in the field. Experimental results indicate that DBD is very efficient in converting NO to NO2. More than 90% removal of NO, NOx, and SO2 can be simultaneously achieved with CPS. Both sodium sulfide (Na2S) and sodium sulfite (Na2SO3) scrubbing solutions are good for NO2 and SO2 absorption. Energy efficiencies for NOx and SO2 removal are 17 and 18 g/kWh, respectively. The technical feasibility of CPS for simultaneous removal of NO, NO2, and SO2 from gas streams is successfully demonstrated in this study. However, production of carbon monoxide as a side-product (approximately 100 ppm) is found and should be considered.

Pilot scale-SO{sub 2} control by dry sodium bicarbonate injection and an electrostatic precipitator

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

Pliat, M.J.; Wilder, J.M.

2007-10-15

A 500 actual cubic feet gas per minute (acfm) pilot-scale SO{sub 2} control study was undertaken to investigate flue gas desulfurization (FGD) by dry sodium sorbents in 400{sup o}F (204.5{sup o}C) flue gases emitted from a coal fired boiler with flue gas concentrations between 350 and 2500 ppm SO{sub 2}. Powdered sodium alkaline reagents were injected into the hot flue gas downstream of the air preheater and the spent reagents were collected using an electrostatic precipitator. Three different sorbents were used: processed sodium bicarbonate of two particle sizes; solution mined sodium bicarbonate, and processed sodium sesquicarbonate. SO{sub 2} concentrations weremore » measured upstream of the reagent injection, 25-ft (7.62 m) downstream of the injection point, and downstream of the electrostatic precipitator. SO{sub 2} collection efficiencies ranged from 40 to 80% using sodium bicarbonate stoichiometric ratios from 0.5 to 3.0. Much of the in-duct SO{sub 2} removal occurred during the first second of reagent reaction time, indicating that the sulfur dioxide-sodium reaction rates may be faster than have been measured for fixed bed measurements reported in the literature.« less

Alternate approaches for assessing impacts of oil sands development on air quality: A case study using the First Nation Community of Fort McKay.

PubMed

Davidson, Carla; Spink, David

2018-04-01

Previous analyses of continuously measured compounds in Fort McKay, an indigenous community in the Athabasca Oil Sands, have detected increasing concentrations of nitrogen dioxide (NO 2 ) and total hydrocarbons (THC), but not of sulfur dioxide (SO 2 ), ozone (O 3 ), total reduced sulfur compounds (TRS), or particulate matter (aerodynamic diameter <2.5 μm; PM 2.5 ). Yet the community frequently experiences odors, dust, and reduced air quality. The authors used Fort McKay's continuously monitored air quality data (1998-2014) as a case study to assess techniques for air quality analysis that make no assumptions regarding type of change. Linear trend analysis detected increasing concentrations of higher percentiles of NO 2 , nitric oxide (NO), and nitrogen oxides (NO x ), and THC. However, comparisons of all compounds between an early industrial expansion period (1998-2001) and current day (2011-2014) show that concentrations of NO 2 , SO 2 , THC, TRS, and PM 2.5 have significantly increased, whereas concentrations of O 3 are significantly lower. An assessment of the frequency and duration of periods when concentrations of each compound were above a variety of thresholds indicated that the frequency of air quality events is increasing for NO 2 and THC. Assessment of change over time with odds ratios of the 25th, 50th, 75th, and 90th percentile concentrations for each compound compared with an estimate of natural background variability showed that concentrations of TRS, SO 2 , and THC are dynamic, higher than background, and changes are nonlinear and nonmonotonic. An assessment of concentrations as a function of wind direction showed a clear and generally increasing influence of industry on air quality. This work shows that evaluating air quality without assumptions of linearity reveals dynamic changes in air quality in Fort McKay, and that it is increasingly being affected by oil sands operations. Understanding the nature and types of air quality changes occurring in a community or region is essential for the development of appropriate air quality management policies. Time-series trending of air quality data is a common tool for assessing air quality changes and is often used to assess the effectiveness of current emission management programs. The use of this tool, in the context of oil sands development, has significant limitations, and alternate air quality change analysis approaches need to be applied to ensure that the impact of this development on air quality is fully understood so that appropriate emission management actions can be taken.

Differential effects between one week and four weeks exposure to same mass of SO2 on synaptic plasticity in rat hippocampus.

PubMed

Yao, Gaoyi; Yun, Yang; Sang, Nan

2016-07-01

Sulfur dioxide (SO2 ) is a ubiquitous air pollutant. The previous studies have documented the adverse effects of SO2 on nervous system health, suggesting that acutely SO2 inhalation at high concentration may be associated with neurotoxicity and increase risk of hospitalization and mortality of many brain disorders. However, the remarkable features of air pollution exposure are lifelong duration and at low concentration; and it is rarely reported that whether there are different responses on synapse when rats inhaled same mass of SO2 at low concentration with a longer term. In this study, we evaluated the synaptic plasticity in rat hippocampus after exposure to same mass of SO2 at various concentrations and durations (3.5 and 7 mg/m(3) , 6 h/day, for 4 weeks; and 14 and 28 mg/m(3) , 6 h/day, for 1 week). The results showed that the mRNA level of synaptic plasticity marker Arc, glutamate receptors (GRIA1, GRIA2, GRIN1, GRIN2A, and GRIN2B) and the protein expression of memory related kinase p-CaMKпα were consistently inhibited by SO2 both in 1 week and 4 weeks exposure cases; the protein expression of presynaptic marker synaptophysin, postsynaptic density protein 95 (PSD-95), protein kinase A (PKA), and protein kinase C (PKC) were increased in 1 week exposure case, and decreased in 4 weeks exposure case. Our results indicated that SO2 inhalation caused differential synaptic injury in 1 week and 4 weeks exposure cases, and implied the differential effects might result from different PKA- and/or PKC-mediated signal pathway. © 2014 Wiley Periodicals, Inc. Environ Toxicol 31: 820-829, 2016. © 2014 Wiley Periodicals, Inc.

Ozone Monitoring Instrument Observations of Interannual Increases in SO2 Emissions from Indian Coal-fired Power Plants During 2005-2012

NASA Technical Reports Server (NTRS)

Lu, Zifeng; Streets, David D.; de Foy, Benjamin; Krotkov, Nickolay A.

2014-01-01

Due to the rapid growth of electricity demand and the absence of regulations, sulfur dioxide (SO2) emissions from coal-fired power plants in India have increased notably in the past decade. In this study, we present the first interannual comparison of SO2 emissions and the satellite SO2 observations from the Ozone Monitoring Instrument (OMI) for Indian coal-fired power plants during the OMI era of 2005-2012. A detailed unit-based inventory is developed for the Indian coal-fired power sector, and results show that its SO2 emissions increased dramatically by 71 percent during 2005-2012. Using the oversampling technique, yearly high-resolution OMI maps for the whole domain of India are created, and they reveal a continuous increase in SO2 columns over India. Power plant regions with annual SO2 emissions greater than 50 Gg year-1 produce statistically significant OMI signals, and a high correlation (R equals 0.93) is found between SO2 emissions and OMI-observed SO2 burdens. Contrary to the decreasing trend of national mean SO2 concentrations reported by the Indian Government, both the total OMI-observed SO2 and average SO2 concentrations in coal-fired power plant regions increased by greater than 60 percent during 2005-2012, implying the air quality monitoring network needs to be optimized to reflect the true SO2 situation in India.

Estimation of the CO{sub 2} absorption capacities in aqueous 2-(2-aminoethylamino)ethanol and its blends with MDEA and TEA in the presence of SO{sub 2}

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

Bonenfant, D.; Minleault, M.; Hausler, R.

2007-12-15

A study of carbon dioxide (CO{sub 2}) and sulfur dioxide (SO{sub 2})/CO{sub 2} mixtures absorption has been carried out in aqueous 2-(2-aminoethylamino)ethanol (AEE) solution and its blends with N-methyldiethanolamine (MDEA) and triethanolamine (TEA) to estimate the influence of SO{sub 2}, MDEA, and TEA on the CO{sub 2} absorption capacity of the AEE. The CO{sub 2} absorption loading has been estimated in 15 wt % AEE alone and in the presence of either 5 and 10 wt % MDEA or 5 and 10 wt % TEA solutions with 100 vol % CO{sub 2} and 5.03 and 15.02 vol % SO{sub 2}/CO{submore » 2} mixtures at a starting temperature of 296 K and flow rates of 3.067, 3.229, and 3.605 L/min, respectively. The results revealed that the presence of SO{sub 2} in the gas decreases the CO{sub 2} absorption rate and loading in the AEE solution as a function of the concentration of SO{sub 2}. The additions of 5 and 10 wt % of MDEA and TEA do not seem to influence the CO{sub 2} absorption rate in the AEE solution. Moreover, the addition of MDEA increases slightly the CO{sub 2} absorption capacity of AEE, while TEA decreases the absorption capacity of AEE in the absence and presence Of SO{sub 2}. These effects were enhanced with increases of MDEA and TEA. Altogether, the results indicated that the blend of 15 wt % AEE + 10 wt % MDEA represents an interesting solvent which could be used as absorbent for the removal of CO{sub 2} from emission into the atmosphere by industries.« less

Fabrication of gas sensor based on field ionization from SWCNTs with tripolar microelectrode

NASA Astrophysics Data System (ADS)

Cai, Shengbing; Zhang, Yong; Duan, Zhemin

2012-12-01

We report the nanofabrication of a sulfur dioxide (SO2) sensor with a tripolar on-chip microelectrode utilizing a film of single-walled carbon nanotubes (SWCNTs) as the field ionization cathode, where the ion flow current and the partial discharge current generated by the field ionization process of gaseous molecules can be gauged to gas species and concentration. The variation of the sensitivity is less than 4% for all of the tested devices, and the sensor has selectivity against gases such as He, NO2, CO, H2, SO2 and O2. Further, the sensor response presents well-defined and reproducible linear behavior with regard to concentration in the range investigated and a detection limitation of <˜0.5 ppm for SO2. More importantly, a tripolar on-chip microelectrode with SWCNTs as a cathode exhibits an impressive performance with respect to stability and anti-oxidation behavior, which are significantly better than had been possible before in the traditional bipolar sensor under explicit circumstances at room temperature.

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

PubMed

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.

Air pollution and outpatient visits for conjunctivitis: A case-crossover study in Hangzhou, China.

PubMed

Fu, Qiuli; Mo, Zhe; Lyu, Danni; Zhang, Lifang; Qin, Zhenwei; Tang, Qiaomei; Yin, Houfa; Xu, Peiwei; Wu, Lizhi; Lou, Xiaoming; Chen, Zhijian; Yao, Ke

2017-12-01

Conjunctivitis, one of the most common ocular surface diseases, can be caused by many factors. The objective of this study was to investigate the potential association between conjunctivitis and air pollutants. Data of 9737 outpatient visits for conjunctivitis from July 1, 2014 to June 30, 2016 were obtained from the Eye Center of the Second Affiliated Hospital of Zhejiang University School of Medicine, Hangzhou, China. The data were linked to data on the concentrations of carbon monoxide (CO), nitrogen dioxide (NO 2 ), ozone (O 3 ), sulfur dioxide (SO 2 ), and fine particulate matter with a median aerometric diameter of less than 10 and 2.5 μm (PM 10 and PM 2.5 , respectively), which were obtained from the Environmental Protection Department of Zhejiang Province. A time-stratified case-crossover study design and conditional logistic regression were applied to analyze the association between air pollutants and outpatient visits for conjunctivitis. A 10 μg/m 3 increase in PM 10 , PM 2.5 , SO 2 , NO 2 , and CO concentrations on the same day as the hospital visit or on lag days before the hospital visit date was associated with outpatient visits for conjunctivitis. The strongest association was observed between SO 2 and conjunctivitis patients aged 2-5 years. Variation occurs between warm and cold seasons, between genders, and among different age groups. Our study provided evidence that outpatient visits for conjunctivitis were significantly associated with air pollution in Hangzhou, China. Copyright © 2017 Elsevier Ltd. All rights reserved.

Kuwaiti oil fires — Air quality monitoring

NASA Astrophysics Data System (ADS)

Amin, Mohamed B.; Husain, Tahir

Just before the Gulf War was concluded in early March 1991, more than 700 wells in Kuwaiti oil fields were set on fire. About 6 million barrels per day of oil were lost in flames and a large number of pools and lakes were formed. Burning wells in Kuwait emitted several thousand tons of gases such as sulfur dioxide, carbon monoxide, hydrogen sulfide, carbon dioxide, and the oxides of nitrogen, as well as particulate matter, on a daily basis containing partially burned hydrocarbons and metals, all of which were potential for affecting human health and vegetation growth. This paper summarizes the real-time measurements of various gaseous pollutants in the Eastern Province of Saudi Arabia in Dhahran, Abqaiq, Rahimah, Jubail and Tanajib. The statistics on monthly variation of gaseous pollutants showed that pollution concentration in general was high in May 1991. The levels of typical pollutants such as sulfur dioxide (SO 2), carbon monoxide (CO) and nitrogen dioxide (NO 2) in the ambient air were much lower than the permissible limits defined in the Meteorology and Environmental Protection Agency (MEPA) standards. The pollutants measured during the Kuwaiti Oil Fires were compared with the corresponding values measured in the previous year. The comparison shows that although the concentration of gaseous pollutants were within the MEPA limits, during the period of oil well fires, the concentration level increased persistently which might have been harmful for human health. The harmful effects of the major pollutants on human health and vegetation are also briefly discussed in the paper.

Different effects of long-term exposures to SO2 and NO2 air pollutants on asthma severity in young adults.

PubMed

Greenberg, Nili; Carel, Rafael S; Derazne, Estela; Bibi, Haim; Shpriz, Manor; Tzur, Dorit; Portnov, Boris A

2016-01-01

Numerous studies demonstrated that exposure to ambient air pollutants contributes to severity and frequency of asthma exacerbations. However, whether common air pollutants, such as nitrogen dioxide (NO2) and sulfur dioxide (SO2), exert differential effects on asthma occurrence and severity is unclear. The aim of this investigation was to determine whether exposure to NO2 and/or SO2 may initiate different long-term effects on prevalence and severity of asthma in young adults. Medical records of 137,040 males, 17 years old, who underwent standard premilitary service health examinations during 1999-2008 were examined. Air-pollution data for NO2 and SO2 were linked to the place of residence of each subject. The influence of specific air pollutants on asthma prevalence and severity was evaluated using bivariate logistic regression, controlling for individuals' sociodemographic attributes. For both ambient air pollutants, there was a significant dose-response effect on severity of asthma at ambient concentrations below the current National Ambient Air Quality Standards. However, in residential areas with high levels of SO2 (13.3-592.7µg/m(3)) and high levels of NO2 (27.2-43.2µg/m(3)) the risk of asthma occurrence was significantly higher than that in residential areas with high levels of NO2 (27.2-43.2 µg/m(3)) and intermediate levels (6.7-13.3 µg/m(3)) of SO2 pollution. The effects of exposure to SO2 and NO2 air pollutants on the respiratory airways system appear to differ, with possible implications regarding medical management, even in cases of exposure to mixtures of these pollutants.

Global Troposphere Experiment Project

NASA Technical Reports Server (NTRS)

Bandy, Alan R.; Thornton, Donald C.

1997-01-01

For the Global Troposphere Experiment project Pacific Exploratory Measurements West B (PEM West B), we made determinations of sulfur dioxide (SO2) and dimethyl sulfide (DMS) using gas chromatography-mass spectrometry with isotopically labelled internal standards. This technique provides measurements with precision of 1 part-per-trillion by volume below 20 pptv and 1% above 20 pptv. Measurement of DMS and SO2 were performed with a time cycle of 5-6 minutes with intermittent zero checks. The detection limits were about 1 pptv for SO2 and 2 pptv for DMS. Over 700 measurements of each compound were made in flight. Volcanic impacts on the upper troposphere were again found as a result of deep convection in the tropics. Extensive emission of SO2 from the Pacific Rim land masses were primarily observed in the lower well-mixed part of the boundary layer but also in the upper part of the boundary layer. Analyses of the SO2 data with aerosol sulfate, beryllium-7, and lead-210 indicated that SO2, contributed to half or more of the observed total oxidized sulfur (SO2 plus aerosol sulfate) in free tropospheric air. Cloud processing and rain appeared to be responsible for lower SO2 levels between 3 and 8.5 km than above or below this region. During both phases of PEM-West, dimethyl sulfide did not appear to be a major source of sulfur dioxide in the upper free troposphere over the western Pacific Ocean. In 1991 the sources Of SO2 at high altitude appeared to be both anthropogenic and volcanic with an estimated 1% being solely from DMS. The primary difference for the increase in the DMS source was the very low concentration of SO2 at high altitude. In the midlatitude region near the Asian land masses, DMS in the mixed layer was lower than in the tropical region of the western Pacific. Convective cloud systems near volcanoes in the tropical convergence in the western Pacific troposphere were a major source of SO2 at high altitudes during PEM-West B. High levels of SO2 were observed in several instances with large number concentrations of ultrafine CN above 9 km in the tropical convergence zone. Conversion of SO2, by OH to SO3 and subsequently to sulfuric acid may have been enhanced by lightning-produced NO levels exceeding 1 part per billion. Coupling of strong convection and volcanic sources of SO2 apparently is an important source of new particle formation at high altitude in the tropical convergence zone.

Effectiveness of Emission Controls to Reduce the Atmospheric Concentrations of Mercury.

PubMed

Castro, Mark S; Sherwell, John

2015-12-15

Coal-fired power plants in the United States are required to reduce their emissions of mercury (Hg) into the atmosphere to lower the exposure of Hg to humans. The effectiveness of power-plant emission controls on the atmospheric concentrations of Hg in the United States is largely unknown because there are few long-term high-quality atmospheric Hg data sets. Here, we present the atmospheric concentrations of Hg and sulfur dioxide (SO2) measured from 2006 to 2015 at a relatively pristine location in western Maryland that is several (>50 km) kilometers downwind of power plants in Ohio, Pennsylvania, and West Virginia. Annual average atmospheric concentrations of gaseous oxidized mercury (GOM), SO2, fine particulate mercury (PBM2.5), and gaseous elemental mercury (GEM) declined by 75%, 75%, 43%, and 13%, respectively, and were strongly correlated with power-plant Hg emissions from the upwind states. These results provide compelling evidence that reductions in Hg emissions from power plants in the United States had their intended impact to reduce regional Hg pollution.

Modeling emissions from CAFO poultry farms in Poland and evaluating potential risk to surrounding populations.

PubMed

Pohl, H R; Citra, M; Abadin, H A; Szadkowska-Stańczyk, I; Kozajda, A; Ingerman, L; Nguyen, A; Murray, H E

2017-03-01

The world-wide use of concentrated animal feeding operations (CAFOs) for livestock production demands the need to evaluate the potential impact to public health. We estimated the exposure of various airborne pollutants for populations residing in close proximity to 10 poultry CAFOs located in Central Poland. Ammonia (NH 3 ), carbon dioxide (CO 2 ), carbon monoxide (CO), hydrogen sulfide (H 2 S), methane (CH 4 ), nitrogen dioxide (NO 2 ), nitrous oxide (N 2 O), sulfur dioxide (SO 2 ), and organic dust were the pollutants of interest for this study. Because no monitoring data were available, we used the steady-state Gaussian dispersion model AERMOD to estimate pollutant concentrations for the exposed population in order to calculate the hazard index (HI) for a combined mixture of chemicals. Our results indicate that while the levels of certain pollutants are expected to exceed background levels commonly found in the environment they did not result in calculated hazard indexes which exceeded unity suggesting low potential for adverse health effects for the surrounding community for the mixture of chemicals. The study was conducted through a cooperation between the Agency for Toxic Substances and Disease Registry (ATSDR) in the USA and the Nofer Institute of Occupational Medicine (NIOM) in Poland. Copyright © 2016. Published by Elsevier Inc.

Fully Converting Graphite into Graphene Oxide Hydrogels by Preoxidation with Impure Manganese Dioxide.

PubMed

Sun, Jiaojiao; Yang, Ningxin; Sun, Zhe; Zeng, Mengqi; Fu, Lei; Hu, Chengguo; Hu, Shengshui

2015-09-30

Potassium permanganate (KMnO4) has been proved to be an efficient oxidant for converting graphite into graphite oxide, but its slow diffusion in the interlayer of graphite seriously restricts the production of graphene oxide (GO). Here, we demonstrate that the preoxidation of graphite by impure manganese dioxide (MnO2) in a mixture of concentrated sulfuric acid (H2SO4) and phosphorus pentoxide (P2O5) can efficiently improve the synthesis of GO when KMnO4 is employed as the oxidant. The prepared honey-like GO hydrogels possess a high yield of single-layer sheets, large sizes (average lateral size up to 20 μm), wide ranges of stable dispersion concentrations (from dilute solutions, viscous hydrogels, to dry films), and good conductivity after reduction (~2.9 × 10(4) S/m). The mechanism for the improved synthesis of GO by impure MnO2 was explored. The enhanced exfoliation and oxidation of graphite by oxidative Mn ions (mainly Mn(3+)), which are synergistically produced by the reaction of impure MnO2 with H2SO4 and P2O5, are found to be responsible for the improved synthesis of such GO hydrogels. Particularly, preoxidized graphite (POG) can be partially dispersed in water with sonication, which allows the facile construction of flexible and highly conductive graphene nanosheet film electrodes with excellent electrochemical sensing properties.

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

PubMed

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.

Assessment of air quality benefits from national air pollution control policies in China. Part II: Evaluation of air quality predictions and air quality benefits assessment

NASA Astrophysics Data System (ADS)

Wang, Litao; Jang, Carey; Zhang, Yang; Wang, Kai; Zhang, Qiang; Streets, David; Fu, Joshua; Lei, Yu; Schreifels, Jeremy; He, Kebin; Hao, Jiming; Lam, Yun-Fat; Lin, Jerry; Meskhidze, Nicholas; Voorhees, Scott; Evarts, Dale; Phillips, Sharon

2010-09-01

Following the meteorological evaluation in Part I, this Part II paper presents the statistical evaluation of air quality predictions by the U.S. Environmental Protection Agency (U.S. EPA)'s Community Multi-Scale Air Quality (Models-3/CMAQ) model for the four simulated months in the base year 2005. The surface predictions were evaluated using the Air Pollution Index (API) data published by the China Ministry of Environmental Protection (MEP) for 31 capital cities and daily fine particulate matter (PM 2.5, particles with aerodiameter less than or equal to 2.5 μm) observations of an individual site in Tsinghua University (THU). To overcome the shortage in surface observations, satellite data are used to assess the column predictions including tropospheric nitrogen dioxide (NO 2) column abundance and aerosol optical depth (AOD). The result shows that CMAQ gives reasonably good predictions for the air quality. The air quality improvement that would result from the targeted sulfur dioxide (SO 2) and nitrogen oxides (NO x) emission controls in China were assessed for the objective year 2010. The results show that the emission controls can lead to significant air quality benefits. SO 2 concentrations in highly polluted areas of East China in 2010 are estimated to be decreased by 30-60% compared to the levels in the 2010 Business-As-Usual (BAU) case. The annual PM 2.5 can also decline by 3-15 μg m -3 (4-25%) due to the lower SO 2 and sulfate concentrations. If similar controls are implemented for NO x emissions, NO x concentrations are estimated to decrease by 30-60% as compared with the 2010 BAU scenario. The annual mean PM 2.5 concentrations will also decline by 2-14 μg m -3 (3-12%). In addition, the number of ozone (O 3) non-attainment areas in the northern China is projected to be much lower, with the maximum 1-h average O 3 concentrations in the summer reduced by 8-30 ppb.

78 FR 28173 - Approval and Promulgation of Air Quality Implementation Plans; Indiana; Sulfur Dioxide and...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-05-14

...-9811-5] Approval and Promulgation of Air Quality Implementation Plans; Indiana; Sulfur Dioxide and Nitrogen Dioxide Ambient Air Quality Standards AGENCY: Environmental Protection Agency (EPA). ACTION... implementation plan (SIP) for nitrogen dioxide (NO 2 ) and sulfur dioxide (SO 2 ) under the Clean Air Act. This...

Sulfur Dioxide Capture by Heterogeneous Oxidation on Hydroxylated Manganese Dioxide.

PubMed

Wu, Haodong; Cai, Weimin; Long, Mingce; Wang, Hairui; Wang, Zhiping; Chen, Chen; Hu, Xiaofang; Yu, Xiaojuan

2016-06-07

Here we demonstrate that sulfur dioxide (SO2) is efficiently captured via heterogeneous oxidation into sulfate on the surface of hydroxylated manganese dioxide (MnO2). Lab-scale activity tests in a fluidized bed reactor showed that the removal efficiency for a simulated flue gas containing 5000 mg·Nm(-3) SO2 could reach nearly 100% with a GHSV (gas hourly space velocity) of 10000 h(-1). The mechanism was investigated using a combination of experimental characterizations and theoretical calculations. It was found that formation of surface bound sulfate proceeds via association of SO2 with terminal hydroxyls. Both H2O and O2 are essential for the generation of reactive terminal hydroxyls, and the indirect role of O2 in heterogeneous SO2 oxidation at low temperature was also revealed. We propose that the high reactivity of terminal hydroxyls is attributed to the proper surface configuration of MnO2 to adsorb water with degenerate energies for associative and dissociative states, and maintain rapid proton dynamics. Viability analyses suggest that the desulfurization method that is based on such a direct oxidation reaction at the gas/solid interface represents a promising approach for SO2 capture.

Response of SO2 and Particulate Air Pollution to Local and Regional Emission Controls: A Case Study in Maryland

NASA Technical Reports Server (NTRS)

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.

Using satellite-based measurements to explore ...

EPA Pesticide Factsheets

New particle formation (NPF) can potentially alter regional climate by increasing aerosol particle (hereafter particle) number concentrations and ultimately cloud condensation nuclei. The large scales on which NPF is manifest indicate potential to use satellite-based (inherently spatially averaged) measurements of atmospheric conditions to diagnose the occurrence of NPF and NPF characteristics. We demonstrate the potential for using satellite-measurements of insolation (UV), trace gas concentrations (sulfur dioxide (SO2), nitrogen dioxide (NO2), ammonia (NH3), formaldehyde (HCHO), ozone (O3)), aerosol optical properties (aerosol optical depth (AOD), Ångström exponent (AE)), and a proxy of biogenic volatile organic compound emissions (leaf area index (LAI), temperature (T)) as predictors for NPF characteristics: formation rates, growth rates, survival probabilities, and ultrafine particle (UFP) concentrations at five locations across North America. NPF at all sites is most frequent in spring, exhibits a one-day autocorrelation, and is associated with low condensational sink (AOD×AE) and HCHO concentrations, and high UV. However, there are important site-to-site variations in NPF frequency and characteristics, and in which of the predictor variables (particularly gas concentrations) significantly contribute to the explanatory power of regression models built to predict those characteristics. This finding may provide a partial explanation for the reported spatia

Advances in the study on endogenous sulfur dioxide in the cardiovascular system.

PubMed

Tian, Hong

2014-01-01

This review summarized the current advances in understanding the role of the novel gasotransmitter, sulfur dioxide (SO2), in the cardiovascular system. Articles on the advances in the study of the role of endogenous sulfur dioxide in the cardiovascular system were accessed from PubMed and CNKI from 2003 to 2013, using keywords such as "endogenous sulfur dioxide" and "cardiovascular system". Articles with regard to the role of SO2 in the regulation of cardiovascular system were selected. Recently, scientists discovered that an endogenous SO2 pathway is present in the cardiovascular system and exerts physiologically significant effects, such as regulation of the cardiac function and the pathogenesis of various cardiopulmonary diseases such as hypoxic pulmonary hypertension, hypertension, coronary atherosclerosis, and cardiac ischemia-reperfusion (I/R) injury, in the cardiovascular system. Endogenous SO2 is a novel member of the gasotransmitter family in addition to the nitric oxide (NO), carbon monoxide (CO), and hydrogen sulfide (H2S). Studies indicated that it has a role in regulating the cardiovascular disease.

Homogeneous graft copolymerization of styrene onto cellulose in a sulfur dioxide-diethylamine-dimethyl sulfoxide cellulose solvent

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

Tsuzuki, M.; Hagiwara, I.; Shiraishi, N.

1980-12-01

Graft copolymerization of styrene onto cellulose was studied in a homogeneous system (SO/sub 2/(liquid)- diethylamine (DEA)-dimethyl sulfoxide (DMSO) medium)) by ..gamma..-ray mutual irradiation technique. At the same time, homopolymerization of styrene was also examined separately in DMSO, SO/sub 2/-DMSO, DEA-DMSO, and SO/sub 2/-DEA-DMSO media by the same technique. Polymerization of styrene hardly occurs on concentrations above 10 mole SO/sub 2/-DEA complex per mole glucose unit. Maximum percent grafting was obtained in concentrations of 4 mole, after which it decreased rapidly. Total conversion and percent grafting increased with the irradiation time. The value (=0.55) of the slope of the total conversionmore » rate plotted against the dose was only a little higher than the 1/2 which was expected from normal kinetics. No retardation in homopolymerization of styrene in DMSO, SO/sub 2/-DMSO, and DEA-DMSO was evident, while the retardation of homopolymerization in the SO/sub 2/-DEA-DMSO medium was measurable. Sulfur atoms were detected in the polymers obtained in both of SO/sub 2/-DMSO and SO/sub 2/-DEA-DMSO solutions. All of the molecular weights of polymers obtained in the present experiment were very low (3.9 x 10/sup 3/-1.75 x 10/sup 4/).« less

A preliminary assessment of dispersion level of SO 2 in Fars industrial region, south of Iran, by GIS.

PubMed

Dehghani, Mansooreh; Taghizadeh, Mohammad Mehdi; Hashemi, Hassan; Rastgoo, Ebrahim

2013-01-01

The city of Zarghan is located 25 km northeast of Shiraz, southern Iran. Zarghan is affected by numerous pollution sources such as oil refinery, an industrial park, and Shiraz-Tehran highway. The numerous contaminating sources around Zarghan can cause serious local air pollution. Sulfur dioxide gas is an important index of air pollution in cities. Therefore, in order to control and manage Zarghan air quality, it is important to monitor sulfur dioxide concentration in the surrounding area. It is also essential to know about the contribution level of other sources of pollution as well as dispersion radius of pollutants in the area. In this study, the concentration of sulfur dioxide was measured by passive sampling at 10 different stations. These values were interpolated in other parts of the city using ArcGIS software. The results of sampling showed that the concentration of the gas was 60 µgm(-3) around oil refinery. The level was 19 µgm(-3) in region located about 3 km from the oil refinery. It was also demonstrated that the gas concentration was not higher than the standard limit within residential area. On the other hand, the role of the local highway and industrial park was not significant in contaminating air in urban areas.

A Preliminary Assessment of Dispersion Level of SO2 in Fars Industrial Region, South of Iran, by GIS

PubMed Central

Dehghani, Mansooreh; Taghizadeh, Mohammad Mehdi; Rastgoo, Ebrahim

2013-01-01

The city of Zarghan is located 25 km northeast of Shiraz, southern Iran. Zarghan is affected by numerous pollution sources such as oil refinery, an industrial park, and Shiraz-Tehran highway. The numerous contaminating sources around Zarghan can cause serious local air pollution. Sulfur dioxide gas is an important index of air pollution in cities. Therefore, in order to control and manage Zarghan air quality, it is important to monitor sulfur dioxide concentration in the surrounding area. It is also essential to know about the contribution level of other sources of pollution as well as dispersion radius of pollutants in the area. In this study, the concentration of sulfur dioxide was measured by passive sampling at 10 different stations. These values were interpolated in other parts of the city using ArcGIS software. The results of sampling showed that the concentration of the gas was 60 µgm−3 around oil refinery. The level was 19 µgm−3 in region located about 3 km from the oil refinery. It was also demonstrated that the gas concentration was not higher than the standard limit within residential area. On the other hand, the role of the local highway and industrial park was not significant in contaminating air in urban areas. PMID:24163700

Impact of sulfur dioxide and temperature on culturability and viability of Brettanomyces bruxellensis in Wine.

PubMed

Zuehlke, Jesse M; Edwards, Charles G

2013-12-01

Brettanomyces is a major threat to red wine quality, causing off-odors such as "medicinal," "barnyard," or even "sewage" during aging. Although sulfites (SO2) are used to limit spoilage by these yeast cells, reduced storage temperatures may lessen SO2 requirements. To test this hypothesis, a 4 | 4 factorial experimental design with molecular SO2(mSO2) concentration (0.0, 0.2, 0.5, or 1.1 mg/liter) and storage temperature (22, 18, 15, or 10°C) was devised. Of three strains evaluated, B5 was the lone strain to regain culturability following exposure to 0.5 mg/liter mSO2 (18°C), whereas only F3 remained culturable in the absence of mSO2 at 10°C. Application of fluorescence microscopy using two different probes and quantitative PCR assays revealed only a 2-log reduction in metabolically active cells from wines with SO2 that were not culturable on nonselective media. Culturability in these wines eventually returned regardless of the concentration of mSO2 present. In addition, 4-ethylphenol production ceased upon addition of SO2. These findings provide additional support that Brettanomyces can enter a "viable-but-not-culturable" state upon exposure to sulfites. Given the diversity among strains, maintaining conditions of ≤15°C and ≥0.4 mg/liter mSO2 will help limit spoilage by Brettanomyces but will not lead to its complete eradication.

Theoretical constraints on oxygen and carbon dioxide concentrations in the Precambrian atmosphere

NASA Technical Reports Server (NTRS)

Kasting, J. F.

1987-01-01

Simple (one-dimensional) climate models suggest that carbon dioxide concentrations during the Archean must have been at least 100-1000 times the present level to keep the Earth's surface temperature above freezing in the face of decreased solar luminosity. Such models provide only lower bounds on CO2, so it is possible that CO2 levels were substantially higher than this and that the Archean climate was much warmer than today. Periods of extensive glaciation during the early and late Proterozoic, on the other hand, indicate that the climate at these times was relatively cool. To be consistent with climate models CO2 partial pressures must have declined from approximately 0.03 to 0.3 bar around 2.5 Ga ago to between 10(-3) and 10(-2) bar at 0.8 Ga ago. This steep decrease in carbon dioxide concentrations may be inconsistent with paleosol data, which implies that pCO2 did not change appreciably during that time. Oxygen was essentially absent from the Earth's atmosphere and oceans prior to the emergence of a photosynthetic source, probably during the late Archean. During the early Proterozoic the atmosphere and surface ocean were apparently oxidizing, while the deep ocean remained reducing. An upper limit of 6 x 10(-3) bar for pO2 at this time can be derived by balancing the burial rate of organic carbon with the rate of oxidation of ferrous iron in the deep ocean. The establishment of oxidizing conditions in the deep ocean, marked by the disappearance of banded iron formations approximately 1.7 Ga ago, permitted atmospheric oxygen to climb to its present level. O2 concentrations may have remained substantially lower than today, however, until well into the Phanerozoic.

Latitudinal variability of the dynamic linkage between temperature and atmospheric carbon dioxide concentrations - Latitudinal variability

NASA Astrophysics Data System (ADS)

Triacca, Umberto; Di Iorio, Francesca

2018-06-01

In this paper, a novel data-driven approach is used to investigate the presence of spatial differences in the dynamic linkage between temperature and atmospheric carbon dioxide concentrations. This linkage seems to be latitude dependent. The main findings of the study are as follows. In the latitude belts surrounding the equator (0°- 24° N and 0°- 24° S), the link seems very similar. On the opposite, the patterns of the temperature CO2 link in the Arctic is very distant from those concerning the equatorial regions and other latitude bands in the South Hemisphere. This big distance is consistent with the so-called Arctic amplification phenomenon. Further, it is important to underline that this observational data-based analysis provides an independent statistical confirmation of the results from global circulation modelling.

77 FR 72966 - Approval and Promulgation of Air Quality Implementation Plans; Maryland; The 2002 Base Year...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-12-07

... (VOCs), PM 2.5 , coarse particles (PM 10 ), ammonia (NH 3 ), and sulfur dioxide (SO 2 ). EPA has... ), ammonia (NH 3 ), and sulfur dioxide (SO 2 ). [FR Doc. 2012-29611 Filed 12-6-12; 8:45 am] BILLING CODE 6560...

Variations in the methanesulfonate to sulfate molar ratio in submicrometer marine aerosol particles over the south Pacific Ocean

NASA Technical Reports Server (NTRS)

Bates, Timothy S.; Calhoun, Julie A.; Quinn, Patricia K.

1992-01-01

Seawater concentrations of dimethylsulfide (DMS) and atmospheric concentrations of DMS, sulfur dioxide, methanesulfonate (MSA), and non-sea-salt (nss) sulfate were measured over the eastern Pacific Ocean between 105 deg and 110 deg W from 20 deg N to 60 deg S during February and March 1989. Although the samples collected in the Southern Hemisphere appear to be of marine origin, no significant correlation was found between the latitudinal distributions of DMS, SO2, MSA, and nss SO4(2-). However, an inverse correlation was found between atmospheric temperature and the MSA to nss SO4(2-) molar ratio in submicrometer aerosol particles with a decrease in temperature corresponding to an increase in the molar ratio. Although this trend is consistent with laboratory results indicating the favored production of MSA at lower temperatures, it is contrary to Southern Hemisphere baseline station data. This suggests either a decrease in the supply of DMS relative to nonmarine sources of nss SO4(2-) at the baseline stations in winter or additional mechanisms that affect the relative production of MSA and nss SO4(2-).

40 CFR Appendix A-2 to Part 50 - Reference Method for the Determination of Sulfur Dioxide in the Atmosphere (Pararosaniline Method)

Code of Federal Regulations, 2014 CFR

2014-07-01

... rate and the sampling time. The concentration of SO2 in the ambient air is computed and expressed in... tetracetic acid disodium salt (EDTA) and phosphoric acid,(10, 12) and ozone by time delay.(10) Up to 60 µg Fe... requirements of section 7 of 40 CFR part 58, appendix E (Teflon ® or glass with residence time less than 20 sec...

40 CFR Appendix A-2 to Part 50 - Reference Method for the Determination of Sulfur Dioxide in the Atmosphere (Pararosaniline Method)

Code of Federal Regulations, 2012 CFR

2012-07-01

... rate and the sampling time. The concentration of SO2 in the ambient air is computed and expressed in... tetracetic acid disodium salt (EDTA) and phosphoric acid,(10, 12) and ozone by time delay.(10) Up to 60 µg Fe... requirements of section 7 of 40 CFR part 58, appendix E (Teflon ® or glass with residence time less than 20 sec...

40 CFR Appendix A-2 to Part 50 - Reference Method for the Determination of Sulfur Dioxide in the Atmosphere (Pararosaniline Method)

Code of Federal Regulations, 2013 CFR

2013-07-01

... rate and the sampling time. The concentration of SO2 in the ambient air is computed and expressed in... tetracetic acid disodium salt (EDTA) and phosphoric acid,(10, 12) and ozone by time delay.(10) Up to 60 µg Fe... requirements of section 7 of 40 CFR part 58, appendix E (Teflon ® or glass with residence time less than 20 sec...

40 CFR Appendix A-2 to Part 50 - Reference Method for the Determination of Sulfur Dioxide in the Atmosphere (Pararosaniline Method)

Code of Federal Regulations, 2011 CFR

2011-07-01

... rate and the sampling time. The concentration of SO2 in the ambient air is computed and expressed in... tetracetic acid disodium salt (EDTA) and phosphoric acid,(10, 12) and ozone by time delay.(10) Up to 60 µg Fe... requirements of section 7 of 40 CFR part 58, appendix E (Teflon ® or glass with residence time less than 20 sec...

Indoor air pollutants and health in the United Arab Emirates.

PubMed

Yeatts, Karin B; El-Sadig, Mohamed; Leith, David; Kalsbeek, William; Al-Maskari, Fatma; Couper, David; Funk, William E; Zoubeidi, Taoufik; Chan, Ronna L; Trent, Chris B; Davidson, Christopher A; Boundy, Maryanne G; Kassab, Maamoon M; Hasan, Mohamed Y; Rusyn, Ivan; Gibson, Jacqueline MacDonald; Olshan, Andrew F

2012-05-01

Comprehensive global data on the health effects of indoor air pollutants are lacking. There are few large population-based multi-air pollutant health assessments. Further, little is known about indoor air health risks in the Middle East, especially in countries undergoing rapid economic development. To provide multifactorial indoor air exposure and health data, we conducted a population-based study of indoor air pollution and health in the United Arab Emirates (UAE). We conducted a cross-sectional study in a population-based sample of 628 households in the UAE. Indoor air pollutants [sulfur dioxide (SO2), nitrogen dioxide (NO2), hydrogen sulfide (H2S), formaldehyde (HCHO), carbon monoxide (CO), and particulate matter] were measured using passive samplers over a 7-day period. Health information was collected from 1,590 household members via in-person interviews. Participants in households with quantified SO2, NO2, and H2S (i.e., with measured concentrations above the limit of quantification) were twice as likely to report doctor-diagnosed asthma. Participants in homes with quantified SO2 were more likely to report wheezing symptoms {ever wheezing, prevalence odds ratio [POR] 1.79 [95% confidence interval (CI) 1.05, 3.05]; speech-limiting wheeze, POR 3.53 (95% CI: 1.06, 11.74)}. NO2 and H2S were similarly associated with wheezing symptoms. Quantified HCHO was associated with neurologic symptoms (difficulty concentrating POR 1.47; 95% CI: 1.02, 2.13). Burning incense daily was associated with increased headaches (POR 1.87; 95% CI: 1.09, 3.21), difficulty concentrating (POR 3.08; 95% CI: 1.70, 5.58), and forgetfulness (POR 2.68: 95% CI: 1.47, 4.89). This study provides new information regarding potential health risks from pollutants commonly found in indoor environments in the UAE and other countries. Multipollutant exposure and health assessments in cohort studies are needed to better characterize health effects of indoor air pollutants.

Indoor Air Pollutants and Health in the United Arab Emirates

PubMed Central

El-Sadig, Mohamed; Leith, David; Kalsbeek, William; Al-Maskari, Fatma; Couper, David; Funk, William E.; Zoubeidi, Taoufik; Chan, Ronna L.; Trent, Chris B.; Davidson, Christopher A.; Boundy, Maryanne G.; Kassab, Maamoon M.; Hasan, Mohamed Y.; Rusyn, Ivan; Gibson, Jacqueline MacDonald; Olshan, Andrew F.

2012-01-01

Background: Comprehensive global data on the health effects of indoor air pollutants are lacking. There are few large population-based multi–air pollutant health assessments. Further, little is known about indoor air health risks in the Middle East, especially in countries undergoing rapid economic development. Objectives: To provide multifactorial indoor air exposure and health data, we conducted a population-based study of indoor air pollution and health in the United Arab Emirates (UAE). Methods: We conducted a cross-sectional study in a population-based sample of 628 households in the UAE. Indoor air pollutants [sulfur dioxide (SO2), nitrogen dioxide (NO2), hydrogen sulfide (H2S), formaldehyde (HCHO), carbon monoxide (CO), and particulate matter] were measured using passive samplers over a 7-day period. Health information was collected from 1,590 household members via in-person interviews. Results: Participants in households with quantified SO2, NO2, and H2S (i.e., with measured concentrations above the limit of quantification) were twice as likely to report doctor-diagnosed asthma. Participants in homes with quantified SO2 were more likely to report wheezing symptoms {ever wheezing, prevalence odds ratio [POR] 1.79 [95% confidence interval (CI) 1.05, 3.05]; speech-limiting wheeze, POR 3.53 (95% CI: 1.06, 11.74)}. NO2 and H2S were similarly associated with wheezing symptoms. Quantified HCHO was associated with neurologic symptoms (difficulty concentrating POR 1.47; 95% CI: 1.02, 2.13). Burning incense daily was associated with increased headaches (POR 1.87; 95% CI: 1.09, 3.21), difficulty concentrating (POR 3.08; 95% CI: 1.70, 5.58), and forgetfulness (POR 2.68: 95% CI: 1.47, 4.89). Conclusions: This study provides new information regarding potential health risks from pollutants commonly found in indoor environments in the UAE and other countries. Multipollutant exposure and health assessments in cohort studies are needed to better characterize health effects of indoor air pollutants. PMID:22357138

Extraordinary Difference in Reactivity of Ozone (OOO) and Sulfur Dioxide (OSO): A Theoretical Study.

PubMed

Lan, Yu; Wheeler, Steven E; Houk, K N

2011-07-12

Ozone and sulfur dioxide are valence isoelectronic yet show very different reactivity. While ozone is one of the most reactive 1,3-dipoles, SO2 does not react in this way at all. The activation energies of dipolar cycloadditions of sulfur dioxide with either ethylene or acetylene are predicted here by B3LYP, M06-2X, CBS-QB3, and CCSD(T) to be much higher than reactions of ozone. The dipolar cycloaddition of ozone is very exothermic, while that of than sulfur dioxide is endothermic. The prohibitive barriers in the case of SO2 arise from large distortion energies as well as unfavorable interaction energies in the transition states. This arises in part from the HOMO-LUMO gap of sulfur dioxide, which is larger than that of ozone. Valence bond calculations also show that while ozone has a high degree of diradical character, SO2 does not, and is better characterized as a dritterion.

Decreased atmospheric sulfur deposition across the Southeastern U.S.: when will watersheds release stored sulfate?

PubMed

Rice, Karen C; Scanlon, Todd M; Lynch, Jason A; Cosby, Bernard J

2014-09-02

Emissions of sulfur dioxide (SO2) to the atmosphere lead to atmospheric deposition of sulfate (SO4(2-)), which is the dominant strong acid anion causing acidification of surface waters and soils in the eastern United States. Since passage of the Clean Air Act and its Amendments, atmospheric deposition of SO2 in this region has declined by over 80%, but few corresponding decreases in streamwater SO4(2-) concentrations have been observed in unglaciated watersheds. We calculated SO4(2-) mass balances for 27 forested, unglaciated watersheds from Pennsylvania to Georgia, by using total atmospheric deposition (wet plus dry) as input. Many of these watersheds still retain SO4(2-), unlike their counterparts in the northeastern U.S. and southern Canada. Our analysis showed that many of these watersheds should convert from retaining to releasing SO4(2-) over the next two decades. The specific years when the watersheds crossover from retaining to releasing SO4(2-) correspond to a general geographical pattern of later net watershed release from north to south. The single most important variable that explained the crossover year was the runoff ratio, defined as the ratio of annual mean stream discharge to precipitation. Percent clay content and mean soil depth were secondary factors in predicting crossover year. The conversion of watersheds from net SO4(2-) retention to release anticipates more widespread reductions in streamwater SO4(2-) concentrations in this region.

Validating the accuracy of SO2 gas retrievals in the thermal infrared (8-14 μm)

NASA Astrophysics Data System (ADS)

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. The coefficients of this model are used to invert measured radiance spectra to path-concentration on a pixel-by-pixel basis. In order to validate the algorithms, TIR hyperspectral measurements were carried out by measuring sky radiance when looking through gas cells filled with known amounts of SO2. SO2-ALTA was also tested on retrieving SO2 path-concentrations from the Kīlauea volcano, Hawai'i. For cloud-free conditions, all three techniques worked well. In cases where background clouds were present, then only SO2-ALTA was found to provide good results, but only under low atmospheric water vapor column amounts.

An Association Between Long-Term Exposure to Ambient Air Pollution and Mortality From Lung Cancer and Respiratory Diseases in Japan

PubMed Central

Katanoda, Kota; Sobue, Tomotaka; Satoh, Hiroshi; Tajima, Kazuo; Suzuki, Takaichiro; Nakatsuka, Haruo; Takezaki, Toshiro; Nakayama, Tomio; Nitta, Hiroshi; Tanabe, Kiyoshi; Tominaga, Suketami

2011-01-01

Background Evidence for a link between long-term exposure to air pollution and lung cancer is limited to Western populations. In this prospective cohort study, we examined this association in a Japanese population. Methods The study comprised 63 520 participants living in 6 areas in 3 Japanese prefectures who were enrolled between 1983 and 1985. Exposure to particulate matter less than 2.5 µm in aerodynamic diameter (PM2.5), sulfur dioxide (SO2), and nitrogen dioxide (NO2) was assessed using data from monitoring stations located in or nearby each area. The Cox proportional hazards model was used to calculate the hazard ratios associated with the average concentrations of these air pollutants. Results The 10-year average concentrations of PM2.5, SO2, and NO2 before recruitment (1974–1983) were 16.8 to 41.9 µg/m3, 2.4 to 19.0 ppb, and 1.2 to 33.7 ppb, respectively (inter-area range). During an average follow-up of 8.7 years, there were 6687 deaths, including 518 deaths from lung cancer. The hazard ratios for lung cancer mortality associated with a 10-unit increase in PM2.5 (µg/m3), SO2 (ppb), and NO2 (ppb) were 1.24 (95% confidence interval: 1.12–1.37), 1.26 (1.07–1.48), and 1.17 (1.10–1.26), respectively, after adjustment for tobacco smoking and other confounding factors. In addition, a significant increase in risk was observed for male smokers and female never smokers. Respiratory diseases, particularly pneumonia, were also significantly associated with all the air pollutants. Conclusions Long-term exposure to air pollution is associated with lung cancer and respiratory diseases in Japan. PMID:21325732

An association between long-term exposure to ambient air pollution and mortality from lung cancer and respiratory diseases in Japan.

PubMed

Katanoda, Kota; Sobue, Tomotaka; Satoh, Hiroshi; Tajima, Kazuo; Suzuki, Takaichiro; Nakatsuka, Haruo; Takezaki, Toshiro; Nakayama, Tomio; Nitta, Hiroshi; Tanabe, Kiyoshi; Tominaga, Suketami

2011-01-01

Evidence for a link between long-term exposure to air pollution and lung cancer is limited to Western populations. In this prospective cohort study, we examined this association in a Japanese population. The study comprised 63 520 participants living in 6 areas in 3 Japanese prefectures who were enrolled between 1983 and 1985. Exposure to particulate matter less than 2.5 µm in aerodynamic diameter (PM(2.5)), sulfur dioxide (SO(2)), and nitrogen dioxide (NO(2)) was assessed using data from monitoring stations located in or nearby each area. The Cox proportional hazards model was used to calculate the hazard ratios associated with the average concentrations of these air pollutants. The 10-year average concentrations of PM(2.5), SO(2), and NO(2) before recruitment (1974-1983) were 16.8 to 41.9 µg/m(3), 2.4 to 19.0 ppb, and 1.2 to 33.7 ppb, respectively (inter-area range). During an average follow-up of 8.7 years, there were 6687 deaths, including 518 deaths from lung cancer. The hazard ratios for lung cancer mortality associated with a 10-unit increase in PM(2.5) (µg/m(3)), SO(2) (ppb), and NO(2) (ppb) were 1.24 (95% confidence interval: 1.12-1.37), 1.26 (1.07-1.48), and 1.17 (1.10-1.26), respectively, after adjustment for tobacco smoking and other confounding factors. In addition, a significant increase in risk was observed for male smokers and female never smokers. Respiratory diseases, particularly pneumonia, were also significantly associated with all the air pollutants. Long-term exposure to air pollution is associated with lung cancer and respiratory diseases in Japan.

Air pollution and general practitioner access and utilization: a population based study in Sarnia, 'Chemical Valley,' Ontario

PubMed Central

2011-01-01

Background Health impacts of poor environmental quality have been identified in studies around the world and in Canada. While many of the studies have identified associations between air pollution and mortality or morbidity, few have focused on the role of health care as a potential moderator of impacts. This study assessed the determinants of health care access and utilization in the context of ambient air pollution in Sarnia, Ontario, Canada. Methods Residents of Sarnia participated in a Community Health Study administered by phone, while several ambient air pollutants including nitrogen dioxide (NO2), sulphur dioxide (SO2) and the volatile organic compounds benzene, toluene, ethylbenzene, mp- and o-xylene (BTEX) were monitored across the city. Land Use Regression models were used to estimate individual exposures to the measured pollutants and logistic regression models were utilized to assess the relative influence of environmental, socioeconomic and health related covariates on general practitioner access and utilization outcomes. Results The results show that general practitioner use increased with levels of exposure to nitrogen dioxide (NO2- Odds Ratio [OR]: 1.16, p < 0.05) and sulphur dioxide (SO2- OR: 1.61, p < 0.05). Low household income was a stronger predictor of having no family doctor in areas exposed to high concentrations of NO2 and SO2. Respondents without regular care living in high pollution areas were also more likely to report travelling or waiting for care in excess of 20 minutes (OR: 3.28, p < 0.05) than their low exposure counterparts (OR: 1.11, p > 0.05). Conclusions This study provides evidence for inequitable health care access and utilization in Sarnia, with particular relevance to its situation as a sentinel high exposure environment. Levels of exposure to pollution appears to influence utilization of health care services, but poor access to primary health care services additionally burden certain groups in Sarnia, Ontario, Canada. PMID:21827645

A Lewis acid β-diiminato-zinc-complex as all-rounder for co- and terpolymerisation of various epoxides with carbon dioxide.

PubMed

Reiter, M; Vagin, S; Kronast, A; Jandl, C; Rieger, B

2017-03-01

A β-diiminato-zinc-N(SiMe 3 ) 2 complex ( 1 ) was synthesised and fully characterised, including an X-ray diffraction study. The activity of catalyst 1 towards the coupling reaction of CO 2 and various epoxides, including propylene oxide (PO), cyclohexene oxide (CHO), styrene oxide (SO), limonene oxide (LO), octene oxide (OO) and epichlorohydrin (ECH), was investigated. Terpolymerisation of CO 2 , PO and LO, as well as CO 2 , CHO and PO, was successfully realised, resulting in polymers with adjustable glass transition temperatures and transparencies. Reaction conditions such as temperature, pressure and catalyst concentration were varied to find the optimal reaction values, especially regarding LO/CO 2 . In situ IR experiments hinted that at 60 °C and a critical LO concentration, polymerisation and depolymerisation are in an equilibrium (ceiling effect). Pressurising catalyst 1 with carbon dioxide resulted in a dimeric catalyst ( 2 ) with a OSiMe 3 group as a new initiator. Homopolymerisation of different epoxides was carried out in order to explain the reactivity concerning copolymerisation reaction of CO 2 and epoxides.

Cardiovascular diseases and air pollution in Novi Sad, Serbia.

PubMed

Jevtić, Marija; Dragić, Nataša; Bijelović, Sanja; Popović, Milka

2014-04-01

A large body of evidence has documented that air pollutants have adverse effect on human health as well as on the environment. The aim of this study was to determine whether there was an association between outdoor concentrations of sulfur dioxide (SO2) and nitrogen dioxide (NO2) and a daily number of hospital admissions due to cardiovascular diseases (CVD) in Novi Sad, Serbia among patients aged above 18. The investigation was carried out during over a 3-year period (from January 1, 2007 to December 31, 2009) in the area of Novi Sad. The number (N = 10 469) of daily CVD (ICD-10: I00-I99) hospital admissions was collected according to patients' addresses. Daily mean levels of NO2 and SO2, measured in the ambient air of Novi Sad via a network of fixed samplers, have been used to put forward outdoor air pollution. Associations between air pollutants and hospital admissions were firstly analyzed by the use of the linear regression in a single polluted model, and then trough a single and multi-polluted adjusted generalized linear Poisson model. The single polluted model (without confounding factors) indicated that there was a linear increase in the number of hospital admissions due to CVD in relation to the linear increase in concentrations of SO2 (p = 0.015; 95% confidence interval (95% CI): 0.144-1.329, R(2) = 0.005) and NO2 (p = 0.007; 95% CI: 0.214-1.361, R(2) = 0.007). However, the single and multi-polluted adjusted models revealed that only NO2 was associated with the CVD (p = 0.016, relative risk (RR) = 1.049, 95% CI: 1.009-1.091 and p = 0.022, RR = 1.047, 95% CI: 1.007-1.089, respectively). This study shows a significant positive association between hospital admissions due to CVD and outdoor NO2 concentrations in the area of Novi Sad, Serbia.

REMOTE SENSING OF SULFUR DIOXIDE EFFECTS ON VEGETATION: SPECTRORADIOMETRY

EPA Science Inventory

Remote measurements of spectral reflectance were made in a laboratory to study sulfur dioxide (SO2) effects on the foliage of soybean (Glycine max (L.) Merr.) and winter wheat (Triticum aestivum) plants. The relationship between spectral reflectance and foliar injury from SO2 was...

Guidance for 1-Hour Sulfur Dioxide (SO2) Nonattainment Area State Implementation Plans (SIP) Submissions

EPA Pesticide Factsheets

The document is intended to provide guidance and recommendations to state, local and tribal governments for the development of SIPs and tribal implementation plans (TIPs) under the 2010 1-hour primary NAAQS for Sulfur Dioxide (SO2).

Maximizing sinter plant operating flexibility through emissions trading and air modeling

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

Schewe, G.J.; Wagner, J.A.; Heron, T.

1998-12-31

This paper provides details on the dispersion modeling analysis performed to demonstrate air quality impacts associated with an emission trading scheme for a sintering operation in Youngstown, Ohio. The emission trade was proposed to allow the sinter plant to expand its current allowable sulfur dioxide (SO2) emissions while being offset with SO{sub 2} emissions from boilers at a nearby shutdown steel mill. While the emission trade itself was feasible and the emissions required for the offset were available (the boiler shutdown and their subsequent SO{sub 2} emission credits were never claimed, banked, or used elsewhere), the second criteria for determiningmore » compliance was a demonstration of minimal air quality impact. The air analysis combined the increased ambient SO{sub 2} concentrations of the relaxed sinter plant emissions with the offsetting air quality of the shutdown boilers to yield the net air quality impacts. To test this net air impact, dispersion modeling was performed treating the sinter plant SO{sub 2} emissions as positive and the shutdown boiler SO{sub 2} emissions as negative. The results of the modeling indicated that the ambient air concentrations due to the proposed emissions increase will be offset by the nearby boiler emissions to levels acceptable under EPA`s offset policy Level 2 significant impact concentrations. Therefore, the dispersion modeling demonstrated that the emission trading scheme would not result in significant air quality impacts and maximum operating flexibility was provided to the sintering facility.« less

Modeling sulfur dioxide concentrations in Mt. Rainier area during prevent

NASA Astrophysics Data System (ADS)

Givati, Reuven; Flocchini, Robert G.; Cahill, Thomas A.

The MATHEW/ADPIC models (a diagnostic wind model and a particle model) which were developed at Lawrence Livermore National Laboratory, were used to compute SO 2 concentrations in the Mt Rainier area during PREVENT (Pacific Northwest Regional Visibility Experiment Using Natural Tracers, June to September 1990). The modeled concentrations were compared to measured concentrations at two sampling locations (Tahoma Woods and Paradise near Mt Rainier) which are located in a valley. The SO 2 sources considered are located along the Puget Sound (Everett, Seattle and Tacoma area) and south of it. New formulations were included in the models for the oxidation of SO 2 and the interpolation of the wind field. Because of the paucity of the meteorological data near the sampling points, an estimation was made of the wind values in the valley, based on the phenomena of wind channeling, mountain and valley winds, and historical wind observations near Mt Rainier. The models were run for several non-rainy days during the PREVENT period when large SO 2 concentrations were observed, and for other special cases. Out of 14 days for which the emissions of the previous night were taken into account, for 12 days the ratio of the modeled to the measured SO 2 concentrations at Tahoma Woods during the daytime, was in the interval 0.45-2.00, considered a good agreement. However, the agreement at Tahoma Woods during the night, and at Paradise during the day and the night, were not as good. It seems that the wind flow near Tahoma Woods under the stable conditions at night, and near the steep terrain of Paradise, were not modeled correctly, with the limited input of available meteorological observations.

Fact Sheets and Additional Information Regarding the 2012 Decision to Retain the Secondary NAAQS for Nitrogen Dioxide and Sulfur Dioxide

EPA Pesticide Factsheets

On April 3, 2012, EPA sdecided to retain the current secondary national ambient air quality standard (NAAQS) for nitrogen dioxide (NO2) and sulfur dioxide (SO2).This page contains a fact sheet describing that action.

Molecular dynamics study of combustion reactions in supercritical environment. Part 1: Carbon dioxide and water force field parameters refitting and critical isotherms of binary mixtures

DOE PAGES

Masunov, Artem E.; Atlanov, Arseniy Alekseyevich; Vasu, Subith S.

2016-10-04

Oxy-fuel combustion process is expected to drastically increase the energy efficiency and enable easy carbon sequestration. In this technology the combustion products (carbon dioxide and water) are used to control the temperature and nitrogen is excluded from the combustion chamber, so that nitrogen oxide pollutants do not form. Therefore, in oxycombustion the carbon dioxide and water are present in large concentrations in their transcritical state, and may play an important role in kinetics. The computational chemistry methods may assist in understanding these effects, and Molecular Dynamics with ReaxFF force field seem to be a suitable tool for such a study.more » Here we investigate applicability of the ReaxFF to describe the critical phenomena in carbon dioxide and water and find that several nonbonding parameters need adjustment. We report the new parameter set, capable to reproduce the critical temperatures and pressures. Furthermore, the critical isotherms of CO 2/H 2O binary mixtures are computationally studied here for the first time and their critical parameters are reported.« less

Molecular dynamics study of combustion reactions in supercritical environment. Part 1: Carbon dioxide and water force field parameters refitting and critical isotherms of binary mixtures

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

Masunov, Artem E.; Atlanov, Arseniy Alekseyevich; Vasu, Subith S.

Oxy-fuel combustion process is expected to drastically increase the energy efficiency and enable easy carbon sequestration. In this technology the combustion products (carbon dioxide and water) are used to control the temperature and nitrogen is excluded from the combustion chamber, so that nitrogen oxide pollutants do not form. Therefore, in oxycombustion the carbon dioxide and water are present in large concentrations in their transcritical state, and may play an important role in kinetics. The computational chemistry methods may assist in understanding these effects, and Molecular Dynamics with ReaxFF force field seem to be a suitable tool for such a study.more » Here we investigate applicability of the ReaxFF to describe the critical phenomena in carbon dioxide and water and find that several nonbonding parameters need adjustment. We report the new parameter set, capable to reproduce the critical temperatures and pressures. Furthermore, the critical isotherms of CO 2/H 2O binary mixtures are computationally studied here for the first time and their critical parameters are reported.« less

Characterization of particulate and gas exposures of sensitive subpopulations living in Baltimore and Boston.

PubMed

Koutrakis, Petros; Suh, Helen H; Sarnat, Jeremy A; Brown, Kathleen Ward; Coull, Brent A; Schwartz, Joel

2005-12-01

Personal exposures to particulate and gaseous pollutants and corresponding ambient concentrations were measured for 56 subjects living in Baltimore, Maryland, and 43 subjects living in Boston, Massachusetts. The 3 Baltimore cohorts consisted of 20 healthy older adults (seniors), 21 children, and 15 individuals with physician-diagnosed chronic obstructive pulmonary disease (COPD*). The 2 Boston cohorts were 20 healthy seniors and 23 children. All children were 9 to 13 years of age; seniors were 65 years of age or older; and the COPD participants had moderate to severe physician-diagnosed COPD. Personal exposures to particulate matter with aerodynamic diameters less than 2.5 microm (PM2.5), sulfate (SO(4)2-), elemental carbon (EC), ozone (03), nitrogen dioxide (NO2), and sulfur dioxide (SO2) were measured simultaneously for 24 hours/day. All subjects were monitored for 8 to 12 consecutive days. The primary objectives of this study were (1) to characterize the personal particulate and gaseous exposures for individuals sensitive to PM health effects and (2) to assess the appropriateness of exposure assessment strategies for use in PM epidemiologic studies. Personal exposures to multiple pollutants and ambient concentrations were measured for subjects from each cohort from each location. Pollutant data were analyzed using correlation and mixed-model regression analyses. In Baltimore, personal PM2.5 exposures tended to be comparable to (and frequently lower than) corresponding ambient concentrations; in Boston, the personal exposures were frequently higher. Overall, personal exposures to the gaseous pollutants, especially O3 and SO2, were considerably lower than corresponding ambient concentrations because of the lack of indoor sources for these gases and their high removal rate on indoor surfaces. Further, the impact of ambient particles on personal exposure (the infiltration factor) and differences in infiltration factor by city, season, and cohort were investigated. No difference in infiltration factor was found among the cohorts, which suggests that all subjects were exposed to the same fraction of ambient PM2.5 for a given ambient concentration. In addition, the results show significant correlations between ambient PM2.5 concentrations and corresponding personal exposures over time and provide further indication that ambient gaseous pollutant concentrations may be better surrogates for personal PM2.5 exposures, especially personal exposures to PM2.5 of ambient origin, than their respective personal exposures. These results have important implications for PM health effects studies that use regression models including both ambient PM2.5 and gaseous pollutant concentrations as independent variables, because both parameters may be serving as surrogates for PM2.5 exposures.

77 FR 73924 - Approval and Promulgation of Air Quality Implementation Plans; West Virginia; The 2002 Base Year...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-12-12

... particles (PM 10 ), ammonia (NH 3 ) and sulfur dioxide (SO 2 ). EPA has reviewed the results, procedures and... , coarse particles (PM 10 ), ammonia (NH 3 ) and sulfur dioxide (SO 2 ). [FR Doc. 2012-29893 Filed 12-11-12...

Short-term air pollution exposure aggravates Parkinson’s disease in a population-based cohort

PubMed Central

Lee, Hyewon; Myung, Woojae; Kim, Doh Kwan; Kim, Satbyul Estella; Kim, Clara Tammy; Kim, Ho

2017-01-01

Increasing experimental evidence has suggested air pollution as new risk factor for neurological disease. Although long-term exposure is reportedly related to neurological disease, information on association with short-term exposure is scarce. We examined the association of short-term exposure to particles <2.5 μm (PM2.5), nitrogen dioxide (NO2), sulfur dioxide (SO2), ozone (O3), and carbon monoxide (CO) with PD aggravation in Seoul from the National Health Insurance Service–National Sample Cohort, Korea during 2002–2013. PD aggravation cases were defined as emergency hospital admissions for primarily diagnosed PD and analyzed with a case-crossover analysis, designed for rare acute outcomes. Pollutants concentrations on case and control days were compared and effect modifications were explored. A unit increase in 8-day moving average of concentrations was significantly associated with PD aggravation. The association was consistent for PM2.5 (odds ratio [95% confidence interval]: 1.61 [1.14–2.29] per 10 μg/m3), NO2 (2.35 [1.39–3.97] per 10 ppb), SO2 (1.54 [1.11–2.14] per 1 ppb), and CO (1.46 [1.05–2.04] per 0.1 ppm). The associations were stronger in women, patients aged 65–74 years, and cold season, but not significant. In conclusion, short-term air pollution exposure increased risk of PD aggravation, and may cause neurological disease progression in humans. PMID:28300224

Aerosol deposition in the human respiratory tract

NASA Astrophysics Data System (ADS)

Winchester, John W.; Jones, Donald L.; Mu-tian, Bi

1984-04-01

Rising sulfur dioxide emissions from increased coal combustion present risks, not only of acid rain, but also to health by inhalation of the SO 2 and acid to the lung. We are investigating human inhalation of ppm SO 2 concentrations mixed with aerosol of submicrometer aqueous salt droplets to determine the effects on lung function and body chemistry. Unlike some investigators, we emphasize ammonium sulfate and trace element aerosol composition which simulates ambient air; aerosol pH, relative humidity, and temperature control to reveal gas-particle reaction mechanisms; and dose estimates from length of exposure, SO 2 concentration, and a direct measurement of respiratory deposition of aerosol as a function of particle size by cascade impactor sampling and elemental analysis by PIXE. Exposures, at rest or during exercise, are in a walk-in chamber at body temperature and high humidity to simulate Florida's summer climate. Lung function measurement by spirometry is carried out immediately after exposure. The results are significant in relating air quality to athletic performance and to public health in the southeastern United States.

Short-term effect of ambient air pollution on COPD mortality in four Chinese cities

NASA Astrophysics Data System (ADS)

Meng, Xia; Wang, Cuicui; Cao, Dachun; Wong, Chit-Ming; Kan, Haidong

2013-10-01

Ambient air pollution has been associated with increased mortality and morbidity; however, few studies have examined the short-term effect of air pollution specifically on chronic obstructive pulmonary disease (COPD), which is an important cause of mortality and morbidity world wide. In this analysis, we examined the associations between daily air pollution levels [particulate matter less than 10 microns in aerodynamic diameter (PM10), sulfur dioxide (SO2) and nitrogen dioxide (NO2)] and COPD mortality in four Chinese cities. We used Poisson regression models with natural spline smoothing functions to adjust for long-term and seasonal trends of COPD mortality, as well as other time-varying covariates. We did a meta-analysis to obtain the 4-city average estimates. Air pollution (PM10, SO2, and NO2) was found to be associated with increased risk of COPD mortality in these four cities. Using the random-effects model, an increase of 10 μg m-3 of 2-day moving average concentrations of PM10, SO2 and NO2 corresponded to a 0.78% (95% CI, 0.13-1.42), 1.30% (95% CI, 0.61-1.99), and 1.78% (95% CI, 1.10-2.46) increase of COPD mortality, respectively. The concentration-response curves indicated linear associations without threshold. Only NO2 remained significant in the multi-pollutant models. To our knowledge, this is the first multi-city study in Asian developing region to report the short-term effect of air pollution on COPD mortality. Our results contribute to very limited data on the effects of air pollution on COPD mortality for high exposure settings typical in developing countries.

REAL-TIME MEASUREMENT OF AIRWAY RESPONSES TO SULOFUR DIOXIDE (SO2) IN AN INTACT, AWAKE GUINEA PIG MODEL

EPA Science Inventory

Real-time measurment of airway responses to Sulfur Dioxide (SO2) in an intact, awake guinea pig model. J Stanek1,2, Q Krantz2, J Nolan2, D Winsett2, W Watkinson2, and D Costa2. 1College of Veterinary Medicine, NCSU, Raleigh, NC, USA; 2Pulmonary Toxicology Branch, ETD, NHEERL, US...

Methanol Droplet Extinction in Oxygen/Carbon-dioxide/Nitrogen Mixtures in Microgravity: Results from the International Space Station Experiments

NASA Technical Reports Server (NTRS)

Nayagam, Vedha; Dietrich, Daniel L.; Ferkul, Paul V.; Hicks, Michael C.; Williams, Forman A.

2012-01-01

Motivated by the need to understand the flammability limits of condensed-phase fuels in microgravity, isolated single droplet combustion experiments were carried out in the Combustion Integrated Rack Facility onboard the International Space Station. Experimental observations of methanol droplet combustion and extinction in oxygen/carbon-dioxide/nitrogen mixtures at 0.7 and 1 atmospheric pressure in quiescent microgravity environment are reported for initial droplet diameters varying between 2 mm to 4 mm in this study.The ambient oxygen concentration was systematically lowered from test to test so as to approach the limiting oxygen index (LOI) at fixed ambient pressure. At one atmosphere pressure, ignition and some burning were observed for an oxygen concentration of 13% with the rest being nitrogen. In addition, measured droplet burning rates, flame stand-off ratios, and extinction diameters are presented for varying concentrations of oxygen and diluents. Simplified theoretical models are presented to explain the observed variations in extinction diameter and flame stand-off ratios.

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

PubMed

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 requirements of environmental protection, which will be stricter in the future.

Multimodel Surface Temperature Responses to Removal of U.S. Sulfur Dioxide Emissions

NASA Astrophysics Data System (ADS)

Conley, A. J.; Westervelt, D. M.; Lamarque, J.-F.; Fiore, A. M.; Shindell, D.; Correa, G.; Faluvegi, G.; Horowitz, L. W.

2018-03-01

Three Earth System models are used to derive surface temperature responses to removal of U.S. anthropogenic SO2 emissions. Using multicentury perturbation runs with and without U.S. anthropogenic SO2 emissions, the local and remote surface temperature changes are estimated. In spite of a temperature drift in the control and large internal variability, 200 year simulations yield statistically significant regional surface temperature responses to the removal of U.S. SO2 emissions. Both local and remote surface temperature changes occur in all models, and the patterns of changes are similar between models for northern hemisphere land regions. We find a global average temperature sensitivity to U.S. SO2 emissions of 0.0055 K per Tg(SO2) per year with a range of (0.0036, 0.0078). We examine global and regional responses in SO4 burdens, aerosol optical depths (AODs), and effective radiative forcing (ERF). While changes in AOD and ERF are concentrated near the source region (United States), the temperature response is spread over the northern hemisphere with amplification of the temperature increase toward the Arctic. In all models, we find a significant response of dust concentrations, which affects the AOD but has no obvious effect on surface temperature. Temperature sensitivity to the ERF of U.S. SO2 emissions is found to differ from the models' sensitivity to radiative forcing of doubled CO2.

Air pollution and fasting blood glucose: A longitudinal study in China.

PubMed

Chen, Linping; Zhou, Yong; Li, Shanshan; Williams, Gail; Kan, Haidong; Marks, Guy B; Morawska, Lidia; Abramson, Michael J; Chen, Shuohua; Yao, Taicheng; Qin, Tianbang; Wu, Shouling; Guo, Yuming

2016-01-15

Limited studies have examined the associations between air pollutants [particles with diameters of 10 μm or less (PM10), sulphur dioxide (SO2), and nitrogen dioxide (NO2)] and fasting blood glucose (FBG). We collected data for 27,685 participants who were followed during 2006 and 2008. Generalized Estimating Equation models were used to examine the effects of air pollutants on FBG while controlling for potential confounders. We found that increased exposure to NO2, SO2 and PM10 was significantly associated with increased FBG levels in single pollutant models (p<0.001). For exposure to 4 days' average of concentrations, a 100 μg/m(3) increase in SO2, NO2, and PM10 was associated with 0.17 mmol/L (95% CI: 0.15-0.19), 0.53 mmol/L (95% CI: 0.42-0.65), and 0.11 mmol/L (95% CI: 0.07-0.15) increase in FBG, respectively. In the multi-pollutant models, the effects of SO2 were enhanced, while the effects of NO2 and PM10 were alleviated. The effects of air pollutants on FBG were stronger in female, elderly, and overweight people than in male, young and underweight people. In conclusion, the findings suggest that air pollution increases the levels of FBG. Vulnerable people should pay more attention on highly polluted days to prevent air pollution-related health issues. Copyright © 2015 Elsevier B.V. All rights reserved.

Increased resting heart rate with pollutants in a population based study

PubMed Central

Ruidavets, J.; Cassadou, S.; Cournot, M.; Bataille, V.; Meybeck, M.; Ferrieres, J.

2005-01-01

Background: Air pollution is associated with cardiovascular mortality. Changes in the autonomic nervous system may contribute to cardiac arrhythmias and cardiovascular mortality. This study investigated the relations between air pollutant concentrations of sulphur dioxide (SO2), ozone (O3), nitric dioxide (NO2), and resting heart rate (RHR) in a population based study. Methods: A sample of 863 middle aged men and women, living in Toulouse (MONICA centre) area, was randomly recruited. A cross sectional survey on cardiovascular risk factors was carried. RHR was measured twice in a sitting position after a five minute rest. Multivariate analyses with quintiles of RHR were performed using polytomous logistic regression. Models were adjusted for temperature, season, relative humidity, sex, physical activity, blood pressure, C reactive protein, and cardiovascular drugs. Results: For NO2, the OR (odds ratio) (95% CI) associated with an increase of 5 µg/m3 in the current day of medical examination was 1.14 (1.03 to 1.25) in quintile Q5 of RHR compared with Q1, p for trend = 0.003. For SO2, OR was 1.16 (0.94 to 1.44) in Q5 compared with Q1, p for trend = 0.05, and for O3, OR was 0.96 (0.91 to 1.01) in Q5 compared with Q1, p for trend = 0.11. No significant association was seen when the daily mean concentration of NO2, SO2, and O3 was considered during the previous day as well as when day lag 2 or 3 was considered. The cumulative concentration (three consecutive days) of O3 is negatively associated with RHR (p for trend = 0.02). Conclusion: Changes in pulse rate could reflect cardiac rhythm changes and may be part of the pathophysiological link between pollution and cardiovascular mortality. PMID:16020647

Theoretical-Experimental Analysis of the Effects of Grain Boundaries on the Electrical Properties of SOI (Silicon-on-Insulator) MOSFETS.

DTIC Science & Technology

1983-11-01

work on recrystallization of polycrystalline silicon ( polysilicon ) films deposited on silicon-dioxide has demonstrated remarkable improvement in film...quality, and thus has identified another possibly viable 1SO technology for ICs. The polysilicon -on-S10 2 technology not only has the advantages alluded...and consequently higher areal device densities. Virtually all the research to date on polysilicon -on-SiO 2 has concentrated on the

Associations between short-term exposure to nitrogen dioxide and mortality in 17 Chinese cities: the China Air Pollution and Health Effects Study (CAPES).

PubMed

Chen, Renjie; Samoli, Evangelia; Wong, Chit-Ming; Huang, Wei; Wang, Zongshuang; Chen, Bingheng; Kan, Haidong

2012-09-15

Few multi-city studies in Asian developing countries have examined the acute health effects of ambient nitrogen dioxide (NO(2)). In the China Air Pollution and Health Effects Study (CAPES), we investigated the short-term association between NO(2) and mortality in 17 Chinese cities. We applied two-stage Bayesian hierarchical models to obtain city-specific and national average estimates for NO(2). In each city, we used Poisson regression models incorporating natural spline smoothing functions to adjust for long-term and seasonal trend of mortality, as well as other time-varying covariates. We examined the associations by age, gender and education status. We combined the individual-city estimates of the concentration-response curves to get an overall NO(2)-mortality association in China. The averaged daily concentrations of NO(2) in the 17 Chinese cities ranged from 26 μg/m(3) to 67 μg/m(3). In the combined analysis, a 10-μg/m(3) increase in two-day moving averaged NO(2) was associated with a 1.63% [95% posterior interval (PI), 1.09 to 2.17], 1.80% (95% PI, 1.00 to 2.59) and 2.52% (95% PI, 1.44 to 3.59) increase of total, cardiovascular, and respiratory mortality, respectively. These associations remained significant after adjustment for ambient particles or sulfur dioxide (SO(2)). Older people appeared to be more vulnerable to NO(2) exposure. The combined concentration-response curves indicated a linear association. Conclusively, this largest epidemiologic study of NO(2) in Asian developing countries to date suggests that short-term exposure to NO(2) is associated with increased mortality risk. Copyright © 2012 Elsevier Ltd. All rights reserved.

CONSTRUCTION OF AN OXYGEN CHAMBER FOR THE TREATMENT OF PNEUMONIA

PubMed Central

Stadie, William C.

1922-01-01

1. The construction of an oxygen chamber is given. This chamber can be quickly filled with oxygen to any concentration up to 65 per cent and maintained at the desired concentration for an indefinite time. 2. The construction of ventilating system, cooling device, carbon dioxide remover, automatic oxygen analyzer, and filling and maintenance devices is given. 3. The chamber is designed so that pneumonia patients with anoxemia may be placed in it and breathe an atmosphere containing 40 to 60 per cent of oxygen. 4. The chamber is easy of ingress and egress, is economical in cost of operation, and comfortably accomodates patient and attendants so that adequate nursing and medical attention can be given at all times. PMID:19868609

Chronic SO2 inhalation above environmental standard impairs neuronal behavior and represses glutamate receptor gene expression and memory-related kinase activation via neuroinflammation in rats.

PubMed

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. All rights reserved.

Volcanic CO2 Abundance of Kilauea Plume Retrieved by Meand of AVIRIS Data

NASA Technical Reports Server (NTRS)

Spinetti, C.; Carrere, V.; Buongiorno, M. F.; Pieri, D.

2004-01-01

Absorbing the electromagnetic radiation in several regions of the solar spectrum, CO2 plays an important role in the Earth radiation budget since it produces the greenhouse effect. Many natural processes in the Earth s system add and remove carbon dioxide. Overall, measurements of atmospheric carbon dioxide at different sites around the world show an increased carbon dioxide concentration in the atmosphere. At Mauna Loa Observatory (Hawaii) the measured carbon dioxide increased from 315 to 365 ppm, in the period 1958 2000 [Keeling et al., 2001]. While at the large scale, the relationship between CO2 increase and global warming is established [IPCC, 1996], at the local scale, many studies are still needed to understand regional and local sources of carbon dioxide, such as volcanoes. The volcanic areas are particularly rich in carbon dioxide; this is due to magma degassing in the summit craters region of active volcanoes, and to the presence of fractures and active faults [Giammanco et al., 1998]. Several studies estimate a global flux of volcanic CO2 (34+/-24)10(exp 6) tons/day from effusive volcanic emissions, such as the tropospheric volcanic plume (Table 1) [McClelland et al., 1989]. Plumes are a turbulent mixture of gases, solid particles and liquid droplets, emitted continuously at high temperature from summit craters, fumarolic fields or during eruptive episodes. Inside the plume, water vapour represents 70 90% of the volcanic gases. The main gaseous components are CO2, SO2, HCl, H2, H2S, HF, CO, N2 and CH4. Other plume components are volcanic ash, aqueous and acid droplets and solid sulphur-derived particles [Sparks et al., 1997]. Volcanic gases and aerosols are evidences of volcanic activity [Spinetti et al., 2003] and they have important climatic and environmental effects [Fiocco et al., 1994]. For example, Etna volcano is one of the world s major volcanic gas sources [Allard et al., 1991]. New studies on volcanic gaseous emissions have pointed out that a variation of the gas ratio CO2/SO2 is related to eruptive episodes [Caltabiano et al., 1994]. However, measurements and monitoring of volcanic carbon dioxide are difficult and often hazardous, due to the high background presence of atmospheric CO2 and the inaccessibility of volcanic sites. Hyperspectral remote sensing is a suitable technique to overcome the difficulties of ground measurement. It permits a rapid, comprehensive view of volcanic plumes and their evolution over time, detection of all gases with absorption molecular lines within the sensor s multispectral range and, in general, measurement of all the volatile components evolving from craters. The molecular and particle plume components scatter and absorb incident solar radiation. The integral of the radiation difference composes the signal measured by the remote spectrometer. The inversion technique consists of retrieving the plume component concentrations, hence decomposing the signal into the different contributions. The accuracy of remote sensing techniques depends primarily on the sensor capability and sensitivity.

DETERMINATION OF SULFUR DIOXIDE, NITROGEN OXIDES, AND CARBON DIOXIDE IN EMISSIONS FROM ELECTRIC UTILITY PLANTS BY ALKALINE PERMANGANATE SAMPLING AND ION CHROMATOGRAPHY

EPA Science Inventory

A manual 24-h integrated method for determining SO2, NOx, and CO2 in emissions from electric utility plants was developed and field tested downstream from an SO2 control system. Samples were collected in alkaline potassium permanganate solution contained in restricted-orifice imp...

Further evidence for particle nucleation in clear air adjacent to marine cumulus clouds

NASA Astrophysics Data System (ADS)

Perry, Kevin D.; Hobbs, Peter V.

1994-11-01

Observational evidence is presented for the nucleation of condensation nuclei (CN) in the clear air adjacent to an isolated, marine, cumulus cloud. Two separate regions of particle nucleation are identified: one located above the cloud top, and the second located downwind of the cloud near the level of the anvil outflow. The regions of high CN concentrations were located in extremely clean marine air, with unactivated aerosol surface area (excluding the nucleation mode) less than 2 sq micrometers/cu cm, air temperature -31 C, and higher relative humidities than the undisturbed environment. Vertical profile measurements downwind of the cloud showed that CN concentrations at the level of the anvil outflow (4.9 km) were 8 times greater than at any other level between the surface and 5.3 km. A conceptual model is formulated in which aerosol particles, sulfur dioxide (SO2), sulfuric acid vapor (H2SO4), dimethyl sulfide (DMS), and ozone (O3) from the boundary layer are entrained into the cumulus cloud. Total aerosol number concentrations and unactivated aerosol surface area decrease with height in the cloud due to Brownian diffusion and diffusiophoresis of cloud interstitial aerosol to hydrometeors, coalescence scavenging by cloud droplets, collisional scavenging by ice particles, and subsequent removal by precipitation. The air that is detrained from the cloud raises the relative humidity and vents the clean air, SO2, H2SO4, DMS, and O3 to the near-cloud environment. Hydroxyl radicals then oxidize the SO2 and DMS to H2SO4. Under the conditions of high relative humidity, low total aerosol surface area, low temperatures, and high SO2 concentrations near cloud top, significant concentrations of new particles can be produced by homogeneous-bimolecular nucleation of sulfuric acid solution droplets from H2SO4 and H2O vapor molecules. The concentration of CN as a function of time is calculated for the case described in this paper using a bimodal integral nucleation model. The model results show that significant numbers of CN could have been produced within a few hours by the homogeneous-bimolecular nucleation of sulfuric acid solution droplets under the observed conditions provided the concentration of SO2 near cloud top was enhanced by vertical transport.

Association between air pollution and daily mortality and hospital admission due to ischaemic heart diseases in Hong Kong

NASA Astrophysics Data System (ADS)

Tam, Wilson Wai San; Wong, Tze Wai; Wong, Andromeda H. S.

2015-11-01

Ischaemic heart disease (IHD) is one of the leading causes of death worldwide. The effects of air pollution on IHD mortalities have been widely reported. Fewer studies focus on IHD morbidities and PM2.5, especially in Asia. To explore the associations between short-term exposure to air pollution and morbidities and mortalities from IHD, we conducted a time series study using a generalized additive model that regressed the daily numbers of IHD mortalities and hospital admissions on daily mean concentrations of the following air pollutants: nitrogen dioxide (NO2), particulate matter with an aerodynamic diameter less than 10 μm (PM10), particulate matter with an aerodynamic diameter less than 2.5 μm (PM2.5), ozone (O3), and sulfur dioxide (SO2). The relative risks (RR) of IHD deaths and hospital admissions per 10 μg/m3 increase in the concentration of each air pollutant were derived in single pollutant models. Multipollutant models were also constructed to estimate their RRs controlling for other pollutants. Significant RRs were observed for all five air pollutants, ranging from 1.008 to 1.032 per 10 μg/m3 increase in air pollutant concentrations for IHD mortality and from 1.006 to 1.021 per 10 μg/m3 for hospital admissions for IHD. In the multipollutant model, only NO2 remained significant for IHD mortality while SO2 and PM2.5 was significantly associated with hospital admissions. This study provides additional evidence that mortalities and hospital admissions for IHD are significantly associated with air pollution. However, we cannot attribute these health effects to a specific air pollutant, owing to high collinearity between some air pollutants.

Southern Ocean phytoplankton physiology in a changing climate.

PubMed

Petrou, Katherina; Kranz, Sven A; Trimborn, Scarlett; Hassler, Christel S; Ameijeiras, Sonia Blanco; Sackett, Olivia; Ralph, Peter J; Davidson, Andrew T

2016-09-20

The Southern Ocean (SO) is a major sink for anthropogenic atmospheric carbon dioxide (CO 2 ), potentially harbouring even greater potential for additional sequestration of CO 2 through enhanced phytoplankton productivity. In the SO, primary productivity is primarily driven by bottom up processes (physical and chemical conditions) which are spatially and temporally heterogeneous. Due to a paucity of trace metals (such as iron) and high variability in light, much of the SO is characterised by an ecological paradox of high macronutrient concentrations yet uncharacteristically low chlorophyll concentrations. It is expected that with increased anthropogenic CO 2 emissions and the coincident warming, the major physical and chemical process that govern the SO will alter, influencing the biological capacity and functioning of the ecosystem. This review focuses on the SO primary producers and the bottom up processes that underpin their health and productivity. It looks at the major physico-chemical drivers of change in the SO, and based on current physiological knowledge, explores how these changes will likely manifest in phytoplankton, specifically, what are the physiological changes and floristic shifts that are likely to ensue and how this may translate into changes in the carbon sink capacity, net primary productivity and functionality of the SO. Copyright © 2016 Elsevier GmbH. All rights reserved.

Estimating surface NO2 and SO2 mixing ratios from fast-response total column observations and potential application to geostationary missions.

PubMed

Knepp, T; Pippin, M; Crawford, J; Chen, G; Szykman, J; Long, R; Cowen, L; Cede, A; Abuhassan, N; Herman, J; Delgado, R; Compton, J; Berkoff, T; Fishman, J; Martins, D; Stauffer, R; Thompson, A M; Weinheimer, A; Knapp, D; Montzka, D; Lenschow, D; Neil, D

Total-column nitrogen dioxide (NO 2 ) data collected by a ground-based sun-tracking spectrometer system (Pandora) and an photolytic-converter-based in-situ instrument collocated at NASA's Langley Research Center in Hampton, Virginia were analyzed to study the relationship between total-column and surface NO 2 measurements. The measurements span more than a year and cover all seasons. Surface mixing ratios are estimated via application of a planetary boundary-layer (PBL) height correction factor. This PBL correction factor effectively corrects for boundary-layer variability throughout the day, and accounts for up to ≈75 % of the variability between the NO 2 data sets. Previous studies have made monthly and seasonal comparisons of column/surface data, which has shown generally good agreement over these long average times. In the current analysis comparisons of column densities averaged over 90 s and 1 h are made. Applicability of this technique to sulfur dioxide (SO 2 ) is briefly explored. The SO 2 correlation is improved by excluding conditions where surface levels are considered background. The analysis is extended to data from the July 2011 DISCOVER-AQ mission over the greater Baltimore, MD area to examine the method's performance in more-polluted urban conditions where NO 2 concentrations are typically much higher.

Insights into the Electronic Structure of Ozone and Sulfur Dioxide from Generalized Valence Bond Theory: Bonding in O3 and SO2.

PubMed

Takeshita, Tyler Y; Lindquist, Beth A; Dunning, Thom H

2015-07-16

There are many well-known differences in the physical and chemical properties of ozone (O3) and sulfur dioxide (SO2). O3 has longer and weaker bonds than O2, whereas SO2 has shorter and stronger bonds than SO. The O-O2 bond is dramatically weaker than the O-SO bond, and the singlet-triplet gap in SO2 is more than double that in O3. In addition, O3 is a very reactive species, while SO2 is far less so. These disparities have been attributed to variations in the amount of diradical character in the two molecules. In this work, we use generalized valence bond (GVB) theory to characterize the electronic structure of ozone and sulfur dioxide, showing O3 does indeed possess significant diradical character, whereas SO2 is effectively a closed shell molecule. The GVB results provide critical insights into the genesis of the observed difference in these two isoelectronic species. SO2 possesses a recoupled pair bond dyad in the a"(π) system, resulting in SO double bonds. The π system of O3, on the other hand, has a lone pair on the central oxygen atom plus a pair of electrons in orbitals on the terminal oxygen atoms that give rise to a relatively weak π interaction.

Improved sample preparation and rapid UHPLC analysis of SO2 binding carbonyls in wine by derivatisation to 2,4-dinitrophenylhydrazine.

PubMed

Jackowetz, J N; Mira de Orduña, R

2013-08-15

Sulphur dioxide (SO2) is essential for the preservation of wines. The presence of SO2 binding compounds in musts and wines may limit sulphite efficacy leading to higher total SO2 additions, which may exceed SO2 limits permitted by law and pose health risks for sensitive individuals. An improved method for the quantification of significant wine SO2 binding compounds is presented that applies a novel sample treatment approach and rapid UHPLC separation. Glucose, galacturonic acid, alpha-ketoglutarate, pyruvate, acetoin and acetaldehyde were derivatised with 2,4-dinitrophenylhydrazine and separated using a solid core C18 phase by ultra high performance liquid chromatography. Addition of EDTA to samples prevented de novo acetaldehyde formation from ethanol oxidation. Optimised derivatisation duration enhanced reproducibility and allowed for glucose and galacturonic acid quantification. High glucose residues were found to interfere with the recovery of other SO2 binders, but practical SO2 concentrations and red wine pigments did not affect derivatisation efficiency. The calibration range, method accuracy, precision and limits of detection were found to be satisfactory for routine analysis of SO2 binders in wines. The current method represents a significant improvement in the comprehensive analysis of SO2 binding wine carbonyls. It allows for the quantification of major SO2 binders at practical analyte concentrations, and uses a simple sample treatment method that prevents treatment artifacts. Equipment utilisation could be reduced by rapid LC separation while maintaining analytical performance parameters. The improved method will be a valuable addition for the analysis of total SO2 binder pools in oenological samples. Published by Elsevier Ltd.

Adapting a Particle Model for Computing Sulfur Dioxide Concentrations in Mount Rainier Area and Comparing Them to Measured Values

NASA Astrophysics Data System (ADS)

Givati, Reuven

In this work the SO_2 concentrations measured in the Mt. Rainier area during PREVENT Pacific Northwest Regional Visibility Experiment Using Natural Tracers, June to September 1990), were analyzed with the aid of the MATHEW/ADPIC models (a diagnostic wind model and a particle model) developed by Lawrence Livermore National Laboratory. Some changes were made in the models to adapt them to the specific conditions of this experiment. The models were run on a large domain in western Washington, and the SO_2 concentrations were evaluated at two specific points, Tahoma Woods and Paradise in the Nisqually Valley, the only points near Mt. Rainier where SO_2 concentrations were measured during PREVENT. The changes that were made were: including loss rates of SO_2 by oxidation, using different heights of the top of the boundary layer at different locations, enabling limited area of influence of specific meteorological stations when interpolating the wind fields, and including the possibility of reflection of the air "particles", from the top of the mixed layer. Because of the paucity of the meteorological measurements near the sampling points, an estimation was made about the wind behavior in the valley, based on the phenomena of wind channeling, mountain and valley winds, and historical wind measurements near Mt. Rainier. The models were run for several non-rainy days of PREVENT having large SO_2 concentrations, or that were interesting for other reasons. The agreement between the measured and modeled SO_2 concentrations at Tahoma Woods during the daytime periods, was quite good. Out of 14 days, for which the emissions of the previous night were taken into account, for 12 days (86%) the ratio of the modeled to the measured SO_2 concentrations, at Tahoma Woods during the daytime periods, was in the interval 0.45-2.00. The agreement between the modeled and measured SO_2 concentrations at Tahoma Woods during the nights, and at Paradise, during the day and the night, were not good. It seems that the wind flow near Tahoma Woods during the nights (stable conditions), and near Paradise (steep terrain), could not be modeled correctly, with the limited meteorological observations available.

Adsorption separation of carbon dioxide from flue gas by a molecularly imprinted adsorbent.

PubMed

Zhao, Yi; Shen, Yanmei; Ma, Guoyi; Hao, Rongjie

2014-01-01

CO2 separation by molecularly imprinted adsorbent from coal-fired flue gas after desulfurization system has been studied. The adsorbent was synthesized by molecular imprinted technique, using ethanedioic acid, acrylamide, and ethylene glycol dimethacrylate as the template, functional monomer, and cross-linker, respectively. According to the conditions of coal-fired flue gas, the influencing factors, including adsorption temperature, desorption temperature, gas flow rate, and concentrations of CO2, H2O, O2, SO2, and NO, were studied by fixed bed breakthrough experiments. The experimental conditions were optimized to gain the best adsorption performance and reduce unnecessary energy consumption in future practical use. The optimized adsorption temperature, desorption temperature, concentrations of CO2, and gas flow rate are 60 °C, 80 °C, 13%, and 170 mL/min, respectively, which correspond to conditions of practical flue gases to the most extent. The CO2 adsorption performance was nearly unaffected by H2O, O2, and NO in the flue gas, and was promoted by SO2 within the emission limit stipulated in the Chinese emission standards of air pollutants for a thermal power plant. The maximum CO2 adsorption capacity, 0.57 mmol/g, was obtained under the optimized experimental conditions, and the SO2 concentration was 150 mg/m(3). The influence mechanisms of H2O, O2, SO2, and NO on CO2 adsorption capacity were investigated by infrared spectroscopic analysis.

Removing sulfur dioxide from exhaust air

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

Germerdonk, R.; Jonas, A.

A method for removing sulfur oxides from flue gases is described. An absorption solution of glutaric acid buffered to a pH of about 3.5 to 6.5 is used. The concentration of the glutaric acid is from about 40 to 90% of the saturation concentration, its temperature is from about 20 to 25/sup 0/C, it has a concentration of heavy metal ions no more than about 10/sup -6/ mole/1, and to improve the separation of SO/sub 2/ from the absorption solution, steam is introduced into at least one separator in from about 0.01 to 0.1 kg/1 of solution to be desorbed.

A compilation of sulfur dioxide and carbon dioxide emission-rate data from Cook Inlet volcanoes (Redoubt, Spurr, Iliamna, and Augustine), Alaska during the period from 1990 to 1994

USGS Publications Warehouse

Doukas, Michael P.

1995-01-01

Airborne sulfur dioxide (SO2) gas sampling of the Cook Inlet volcanoes (Mt. Spurr, Redoubt, Iliamna, and Augustine) began in 1986 when several measurements were carried out at Augustine volcano during the eruption of 1986 (Rose and others, 1988). More systematic monitoring for SO2 began in March 1990 and for carbon dioxide (CO2) began in June, 1990 at Redoubt Volcano (Brantley, 1990 and Casadevall and others, 1994) and continues to the present. This report contains all of the available daily SO2 and CO2 emission rates determined by the U.S. Geological Survey (USGS) from March 1990 through July 1994. Intermittent measurements (four to six month intervals) at Augustine and Iliamna began in 1990 and continues to the present. Intermittent measurements began at Mt. Spurr volcano in 1991, and were continued at more regular intervals from June, 1992 through the 1992 eruption at the Crater Peak vent to the present.

Classroom Carbon Dioxide Concentration, School Attendance, and Educational Attainment

ERIC Educational Resources Information Center

Gaihre, Santosh; Semple, Sean; Miller, Janice; Fielding, Shona; Turner, Steve

2014-01-01

Background: We tested the hypothesis that classroom carbon dioxide (CO[subscript 2]) concentration is inversely related to child school attendance and educational attainment. Methods: Concentrations of CO[subscript 2] were measured over a 3-5?day period in 60 naturally ventilated classrooms of primary school children in Scotland. Concentrations of…

Method for making an energetic material

DOEpatents

Fox, Robert V [Idaho Falls, ID

2008-03-18

A method for making trinitrotoluene is described, and which includes the steps of providing a source of aqueous nitric acid having a concentration of less than about 95% by weight; mixing a surfactant with the source of aqueous nitric acid so as to dehydrate the aqueous nitric acid to produce a source of nitronium ions; providing a supercritical carbon dioxide environment; providing a source of an organic material to be nitrated to the supercritical carbon dioxide environment; and controllably mixing the source or nitronium ions with the supercritical carbon dioxide environment to nitrate the organic material and produce trinitrotoluene.

Effects of ozone or sulfur dioxide on annual plants of the Mojave Desert. [Camissonia claviformis; Camissonia hirtella; Cryptantha nevadensis; Festuca octoflora; Lepidium lasiocarpum; Baileya pleniradiata; Perityle emoryi; Oenothera californica

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

Thompson, C.R.; Olszyk, D.M.; Kats, G.

1984-10-01

Forty-seven species of annual plants from the Mojave Desert were grown in pots and exposed in open-top field chambers located at Riverside, California to test their relative sensitivity to SO/sub 2/ and O/sub 3/. Exposures were 8 h/day for four or five days at 0, 0.05, 0.1, 0.2, 0.3 and 0.4 ppm O/sub 3/ or 0, 0.2, 0.5, 0.6, 0.8, 1.0 and 1.5 ppm SO/sub 2/. Species differed widely in their response to the pollutants. Three species, Camissonia claviformis, Camissonia hirtella and Cryptantha nevadensis, were quite sensitive to both pollutants, exhibiting leaf injury when exposed to 0.1 ppm O/sub 3/more » or 0.2 ppm SO/sub 2/. Two species: Festuca octoflora and Lepidium lasiocarpum were tolerant to both pollutants, exhibiting no leaf injury with concentrations of 0.3 ppm O/sub 3/ or 1.5 ppm SO/sub 2/. The other species were intermediate in sensitivity, with O/sub 3/ sensitivity not always corresponding to SO/sub 2/ sensitivity. Total sulfur concentration analysis indicated that for 8 of 11 species tested, plants exposed to 0.2 ppm SO/sub 2/ had a higher sulfur concentration than nonexposed plants. Baileya pleniradiata and Perityle emoryi had the greatest increases in sulfur concentration for exposed versus control plants. To test for effects of the environmental and exposure system on plant sensitivity, 29 of the species exposed in the open-top chambers were grown in the ground and exposed with a modified chamberless zonal air pollution (ZAP) system to SO/sub 2/ in the Mojave Desert area near Daggett, California. Exposures were for a total of 37 h over six days to 0, 0.4, 0.8 and 1.0 ppm SO/sub 2/ with exposures only during periods with due west winds. Most of the species were not injured with any of the SO/sub 2/ exposure concentrations used with the ZAP system; only Camissonia claviformis showed injury at 0.8 ppm SO/sub 2/ and Oenothera californica exhibited injury at 1.0 ppm SO/sub 2/.« less

A GIS Based Approach for Assessing the Association between Air Pollution and Asthma in New York State, USA

PubMed Central

Gorai, Amit K.; Tuluri, Francis; Tchounwou, Paul B.

2014-01-01

Studies on asthma have shown that air pollution can lead to increased asthma prevalence. The aim of this study is to examine the association between air pollution (fine particulate matter (PM2.5), sulfur dioxide (SO2) and ozone (O3)) and human health (asthma emergency department visit rate (AEVR) and asthma discharge rate (ADR)) among residents of New York, USA during the period 2005 to 2007. Annual rates of asthma were calculated from population estimates for 2005, 2006, and 2007 and number of asthma hospital discharge and emergency department visits. Population data for New York were taken from US Bureau of Census, and asthma data were obtained from New York State Department of Health, National Asthma Survey surveillance report. Data on the concentrations of PM2.5, SO2 and ground level ozone were obtained from various air quality monitoring stations distributed in different counties. Annual means of these concentrations were compared to annual variations in asthma prevalence by using Pearson correlation coefficient. We found different associations between the annual mean concentration of PM2.5, SO2 and surface ozone and the annual rates of asthma discharge and asthma emergency visit from 2005 to 2007. A positive correlation coefficient was observed between the annual mean concentration of PM2.5, and SO2 and the annual rates of asthma discharge and asthma emergency department visit from 2005 to 2007. However, the correlation coefficient between annual mean concentrations of ground ozone and the annual rates of asthma discharge and asthma emergency visit was found to be negative from 2005 to 2007. Our study suggests that the association between elevated concentrations of PM2.5 and SO2 and asthma prevalence among residents of New York State in USA is consistent enough to assume concretely a plausible and significant association. PMID:24806193

Assessment of ambient air quality in Eskişehir, Turkey.

PubMed

Ozden, O; Döğeroğlu, T; Kara, S

2008-07-01

This paper presents an assessment of air quality of the city Eskişehir, located 230 km southwest to the capital of Turkey. Only five of the major air pollutants, most studied worldwide and available for the region, were considered for the assessment. Available sulphur dioxide (SO(2)), particulate matter (PM), nitrogen dioxide (NO(2)), ozone (O(3)), and non-methane volatile organic carbons (NMVOCs) data from local emission inventory studies provided relative source contributions of the selected pollutants to the region. The contributions of these typical pollution parameters, selected for characterizing such an urban atmosphere, were compared with the data established for other cities in the nation and world countries. Additionally, regional ambient SO(2) and PM concentrations, determined by semi-automatic monitoring at two sites, were gathered from the National Ambient Air Monitoring Network (NAAMN). Regional data for ambient NO(2) (as a precursor of ozone as VOCs) and ozone concentrations, through the application of the passive sampling method, were provided by the still ongoing local air quality monitoring studies conducted at six different sites, as representatives of either the traffic-dense-, or coal/natural gas burning residential-, or industrial/rural-localities of the city. Passively sampled ozone data at a single rural site were also verified with the data from a continuous automatic ozone monitoring system located at that site. Effects of variations in seasonal-activities, newly established railway system, and switching to natural gas usage on the temporal changes of air quality were all considered for the assessment. Based on the comparisons with the national [AQCR (Air Quality Control Regulation). Ministry of Environment (MOE), Ankara. Official Newspaper 19269; 1986.] and a number of international [WHO (World Health Organization). Guidelines for Air Quality. Geneva; 2000. Downloaded in January 2006, website: http://www.who.int/peh/; EU (European Union). Council Directive 1999/30/EC relating to limit values for sulfur dioxide, nitrogen dioxide and lead in ambient air. Of J Eur Communities L 163: 14-30; 29.6.1999; EU (European Union). Council Directive 2002/3/EC relating to ozone in ambient air. Of J Eur Communities. L 67: 14-30; 9.3.2002.; USEPA (U.S. Environmental Protection Agency). National Ambient Air Quality Standards (NAAQS). Downloaded in January 2006, website: http://www.epa.gov/ttn/naaqs/] ambient air standards, among all the pollutants studied, only the annual average SO(2) concentration was found to exceed one specific limit value (EU limit for protection of the ecosystem). A part of the data (VOC/NO(x) ratio), for determining the effects of photochemical interactions, indicated that VOC-limited regime was prevailing throughout the city.

Dose-response of urban trees to sulfur dioxide

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

Temple, P.J.

1972-01-01

Controlled fumigation experiments were conducted to determine the dose-response relationships for four species of urban trees exposed to sulfur dioxide. The species chosen were ginkgo, Norway maple, pin oak, and Chinese elm. Results indicated that resistance to SO/sub 2/ increased among the species in the following order: Chinese elm, Norway maple, ginkgo, pin oak. Elm showed almost 100% leaf necrosis at exposures over 2 ppM for 6 hr, and severe chlorosis and necrosis at 0.25 ppM for 30 days. Fifty percent leaf necrosis occurred on Norway maple at 3 ppM for 6 hr, and on ginkgo at 4 ppM formore » 6 hr, and both species developed moderate marginal chlorosis at 0.50 ppM for 30 days. Injury on pin oak was minor, even at 8 ppM for 8 hr, but at 0.50 ppM for 30 days, a slight overall chlorosis developed on the leaves. The relative susceptibilities of the four species were the same in the long-term as in the short-term exposures. The shapes of the dose-response surfaces indicated that durations of exposure and concentration of the pollutant were of equal importance in producing injury on Chinese elm and probably on pin oak, but on Norway maple and ginkgo, concentration of SO/sub 2/ was of greater importance than the duration of exposure.« less

Air Pollution Is Associated With Ischemic Stroke via Cardiogenic Embolism.

PubMed

Chung, Jong-Won; Bang, Oh Young; Ahn, Kangmo; Park, Sang-Soon; Park, Tai Hwan; Kim, Jae Guk; Ko, Youngchai; Lee, SooJoo; Lee, Kyung Bok; Lee, Jun; Kang, Kyusik; Park, Jong-Moo; Cho, Yong-Jin; Hong, Keun-Sik; Nah, Hyun-Wook; Kim, Dae-Hyun; Cha, Jae-Kwan; Ryu, Wi-Sun; Kim, Dong-Eog; Kim, Joon-Tae; Choi, Jay Chol; Oh, Mi-Sun; Yu, Kyung-Ho; Lee, Byung-Chul; Lee, Ji Sung; Lee, Juneyoung; Park, Hong-Kyun; Kim, Beom Joon; Han, Moon-Ku; Bae, Hee-Joon

2017-01-01

The aim of the study was to assessed the impact of short-term exposure to air pollution on ischemic stroke subtype, while focusing on stroke caused via cardioembolism. From a nationwide, multicenter, prospective, stroke registry database, 13 535 patients with acute ischemic stroke hospitalized to 12 participating centers were enrolled in this study. Data on the hourly concentrations of particulate matter <10 μm, nitrogen dioxide (NO 2 ), sulfur dioxide (SO 2 ), ozone (O 3 ), and carbon monoxide (CO) were collected from 181 nationwide air pollution surveillance stations. The average values of these air pollutants over the 7 days before stroke onset from nearest air quality monitoring station in each patient were used to determine association with stroke subtype. The primary outcome was stroke subtype, including large artery atherosclerosis, small-vessel occlusion, cardioembolism, and stroke of other or undetermined cause. Particulate matter <10 μm and SO 2 concentrations were independently associated with an increased risk of cardioembolic stroke, as compared with large artery atherosclerosis and noncardioembolic stroke. In stratified analyses, the proportion of cases of cardioembolic stroke was positively correlated with the particulate matter <10 μm, NO 2 , and SO 2 quintiles. Moreover, seasonal and geographic factors were related to an increased proportion of cardioembolic stroke, which may be attributed to the high levels of air pollution. Our findings suggest that the short-term exposure to air pollutants is associated with cardioembolic stroke, and greater care should be taken for those susceptible to cerebral embolism during peak pollution periods. Public and environmental health policies to reduce air pollution could help slow down global increasing trends of cardioembolic stroke. © 2016 American Heart Association, Inc.

Holocene Concentrations of Methane in the Atmosphere are in Part Proportional to Concentrations of Sulfur Dioxide and Inversely Proportional to the Oxidizing Capacity of the Atmosphere

NASA Astrophysics Data System (ADS)

Ward, P. L.

2008-12-01

The atmosphere cleans itself by oxidizing pollutants. The primary oxidant is the hydroxyl radical (OH) formed by photodissociation of ozone in the near ultra-violet. Ozone and OH are in limited supply. Sulfur dioxide (SO2) absorbs near ultraviolet light limiting production of OH and reacts immediately with any available OH, forming sulfuric acid. Methane reacts more slowly with OH and will typically not be oxidized until there is little SO2. Thus a high concentration of methane indicates low oxidizing capacity. The rate at which SO2 is injected into the atmosphere controls oxidizing capacity and climate change in four ways: 1. Moderate rate: Large volcanic eruptions (VEI >=6) lower global temperatures for a few years when they are separated by years to decades so the oxidizing capacity of the atmosphere can fully recover. In 1991, Pinatubo volcano in the Philippines erupted 20 Mt SO2 and 491 Mt H2O, the largest volcanic eruption since 1912. The SO2 was oxidized primarily by OH to form a 99% pure aerosol of sulfuric acid and water at an elevation of 20-23 km. This aerosol reflected sunlight, lowering the world's temperature on average 0.4°C for three years. Ozone levels were reduced by 10%. Methane increased by 15 ppb for a year. The e-folding time for SO2 was 35 days. 2. High rate: When large eruptions occur once to several times per year, there is insufficient oxidizing capacity leading to increases in methane and other greenhouse gases and global warming. There were 15 times in the Holocene when large volcanoes erupted on average at least every year for 7 to 21 years. Man is now putting as much SO2 from burning fossil fuels into the atmosphere every year as one large volcano, causing current global warming. The two previous times were from 818-838 AD, the onset of the Medieval Warming Period, and from 180-143 BC, the onset of the Roman Warm Period. 3. Low rate: When there are no large eruptions for decades, the oxidizing capacity can catch up, cleaning the atmosphere, removing most of the methane and other pollutants. A clean atmosphere leads to cooling and drought. The 8.2 ka event is a classic example, but similar decadal droughts around 6.2, 5.8, 5.4, 4.2, and 2.9 ka caused the demise of major civilizations. 4. Extreme rate: Whereas large volcanic eruptions produce 10-1000 km3 of andesitic and silicic tephra, flood basalt eruptions produce as much as 3,000,000 km3 of basalt containing 10 to 100 times more SO2 per km3. The result is runaway global warming, widespread acid rain, and mass extinctions. The link between SO2 and global warming is good news because we have developed many efficient technologies that burn fossil fuels with less SO2 emission and scrub SO2 out of smoke stacks. Efforts to reduce acid rain have been successful in reducing manmade emissions of SO2 by >20% since 1980 and thereby reducing methane concentrations. Sudden increases in methane during the Pleistocene Dansgaard-Oeschger events follow sudden increases in volcanism. High rainfall especially in the Sahara and high methane concentrations in the early Holocene are clearly related to increased volcanism that brought about the end of the Ice Age. Increases in global warming at 3170 BC, 161 BC, and 828 AD are contemporaneous with short-term increases in methane. The rapid increase in SO2 from burning fossil fuels since 1850 can explain much of the corresponding rapid increase in methane. But during the last 5000 years, volcanism has been relatively constant and thus it can not explain the observed gradual increase in methane.

SO 2 oxidation in an entraining cloud model with explicit microphysics

NASA Astrophysics Data System (ADS)

Bower, K. N.; Hill, T. A.; Coe, H.; Choularton, T. W.

A model of the chemical evolution of the droplets in a hill-cap cloud is presented. The chemistry of individual droplets forming on cloud condensation nuclei of differing size and chemical composition is considered, and the take-up of species from the gas phase by the droplets is treated explicity for the droplet population. Oxidation of S(IV) dissolved in cloud droplets is assumed to be dominated by hydrogen peroxide and ozone. Hydrogen peroxide is normally found to be the dominant oxidant for the oxidation of sulphur dioxide (except in the presence of substantial concentrations of ammonia gas, which increases droplet pH and the contribution made by the oxidant ozone). The entrainment of hydrogen peroxide from above the cloud top increases the amount of sulphate produced in conditions where the reaction is otherwise oxidant limited by the availability hydrogen peroxide. These conditions occur when there are high concentrations of sulphur dioxide accompanied by low cloudwater pH values. Within droplets formed on sodium chloride aerosol, reduced levels of acidity lead to an increase in sulphate production as a result of an enhanced reaction between SO 2 and the oxidant ozone. This results in an overall higher increase in cloudwater sulphate than would be expected assuming an even distribution of all reactants amongst the droplets. In addition, concentrations of the hydrogen sulphite ion predicted to occur in the cloudwater can be substantially in excess of those predicted from the bulk cloudwater pH. This is consistent with recent observations.

Imaging volcanic CO2 and SO2

NASA Astrophysics Data System (ADS)

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.

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

EPA Science Inventory

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

Sulfur dioxide emission rates from Kīlauea Volcano, Hawai‘i, 2007–2010

USGS Publications Warehouse

Elias, T.; Sutton, A.J.

2012-01-01

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

Effect of SO2 and Photolysis on Photooxidized Diesel Fuel Secondary Organic Aerosol Composition

NASA Astrophysics Data System (ADS)

MacMillan, A. C.; Blair, S. L.; Lin, P.; Laskin, A.; Laskin, J.; Nizkorodov, S.

2014-12-01

Diesel fuel (DSL) and sulfur dioxide (SO2) are important precursors to secondary organic aerosol (SOA) formation. DSL is often co-emitted with SO2 and NO2, thus it is important to understand the possible effects of SO2 on DSL SOA composition. Additionally, DSL SOA composition can be affected by photochemical aging processes such as photolysis. In this study, DSL SOA was first prepared under dry, high-NOx conditions with various concentrations of SO2 by photooxidation in a smog chamber. The SOA was then stripped of excess oxidants and gaseous organics with a denuder train and the resulting particles were photolyzed at various photolysis times in a quartz flow tube. The SOA composition, photochemical aging, properties, and mass concentration, before and after direct photolysis in the flow tube, were examined using several techniques. High-resolution mass spectrometry (HR-MS) was performed on DSL SOA samples to investigate the effect of SO2 on molecular level composition. SOA composition as a function of photolysis time was measured with an aerosol mass spectrometer (AMS). HR-MS results show that organosulfates are produced in DSL SOA. Both AMS and HR-MS results show that photolysis also has an effect on composition; though, this is more apparent in the HR-MS results than in the AMS results. In summary, both the presence of SO2 and solar radiation has an effect on DSL SOA composition.

Volatile organic compound concentrations in the South Coast Air Basin (CA) during the summers of 1995 and 1996

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

Zielinska, B.; Harshfield, G.; Fujita, E.

1997-12-31

Volatile organic compounds (VOC) were measured in California`s South Coast Air Basin (SoCAB) during the summers of 1995 and 1996 in order to determine the air quality impacts of the introduction in 1996 of California`s Phase 2 reformulated gasoline (RFG). Over 250 canister and 2,4-dinitrophenylhydrazine (DNPH)-impregnated cartridge samples were collected during each sampling campaign at four sampling sites--two source-dominated sites, a downwind receptor site, and a background site. Canister samples were analyzed for methane, speciated volatile hydrocarbons (C{sub 2}-C{sub 12}), carbon monoxide (CO), carbon dioxide (CO{sub 2}), and methyl tert-butyl ether (MTBE). DNPH were analyzed for C{sub 1}-C{sub 7} carbonylmore » compounds. This paper examines the changes in concentrations of C{sub 2}-C{sub 12} hydrocarbons in the SoCAB resulting from the introduction of Phase 2 RFG with particular emphasis on hydrocarbon species that are most affected by the reformulation.« less

Sulfur Mass Balances of Forested Catchments: Improving Predictions of Stream Sulfate Concentrations Through Better Representation of Soil Storage and Release

NASA Astrophysics Data System (ADS)

Scanlon, T. M.; Rice, K. C.; Riscassi, A.; Cosby, B. J., Jr.

2015-12-01

Sulfur dioxide (SO2) emissions in the eastern United States have declined by more than 80% since 1970, when the Clean Air Act first established limits on emissions from stationary and mobile sources. In many areas throughout the northeastern U.S., the resulting declines in sulfate (SO42-) deposition have been accompanied by declines in stream SO42- concentrations. In the southeastern U.S., however, declines in stream SO42- concentrations have not been observed on a widespread basis. In fact, SO42- concentrations continue to increase in many southeastern streams despite decades of declining deposition. This difference in behavior between northeastern and southeastern streams, owing to the distinct geological histories of their catchment soils, was anticipated by the Direct/Delayed Response Project initiated by the U.S. EPA during the early 1980s. At that time, understanding of how catchments store and release SO42- was mostly grounded in theory. Now, with the accumulation of long-term stream chemistry and hydrological datasets in forested catchments, we may develop an empirical basis for characterizing catchment storage and release of SO42-. In particular, are whole-catchment isotherms that described the partitioning between adsorbed and dissolved SO42- (1) linear or non-linear and (2) reversible or irreversible? How do these isotherms vary on a geographical basis? We apply mass balance combined with a simple theoretical framework to infer whole-catchment SO42- isotherms in Virginia and New England. Knowledge of this key soil geochemical property is needed to improve predictions of how catchments will store and export SO42- under changing levels of atmospheric deposition.

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

Code of Federal Regulations, 2010 CFR

2010-07-01

... sampling time. The concentration of SO2 in the ambient air is computed and expressed in micrograms per... tetracetic acid disodium salt (EDTA) and phosphoric acid,(10, 12) and ozone by time delay.(10) Up to 60 µg Fe... requirements of section 7 of 40 CFR part 58, appendix E (Teflon ® or glass with residence time less than 20 sec...

UK hazard assessment for a Laki-type volcanic eruption: modelling results for sulphur dioxide and sulphate aerosol

NASA Astrophysics Data System (ADS)

Witham, Claire; Vieno, Massimo; Schmidt, Anja; Aspinall, Willy; Braban, Christine; Hort, Matthew; Loughlin, Sue

2015-04-01

In response to the recent introduction of large gas-rich volcanic eruptions to the UK National Risk Register a modelling project has been conducted to improve our understanding of potential impacts to the UK from such an eruption on Iceland. A precautionary reasonable worst case eruption scenario based on the 1783-4 Laki eruption has been modelled 80 times using two different atmospheric chemistry and transport models (NAME and EMEP4UK) over 10 years of meteorology. The results provide information on the range of concentrations of sulphur dioxide gas (SO2), sulphate aerosol (SO4) and some halogen species that might be experienced in the UK during such an eruption and the likelihood of key thresholds being exceeded and over what durations. Data for the surface and for a range of key flight levels have been produced. In this presentation we will evaluate the ambient mass concentrations of SO2 and SO4 that could be experienced during and following such an eruption, as well as the likelihood of key health concentration thresholds being exceeded, and the maximum duration that levels could persist for. The prevailing meteorological conditions are the key influence on which parts of the North Atlantic and European region are affected at any time. The results demonstrate that the UK is unlikely to be affected by week after week of significantly elevated concentrations; rather there will a number of short (hours to days) pollution episodes where concentrations would be elevated above Moderate and High air quality index levels at the surface. This pattern fits with the generally changeable nature of the weather in the UK. Consecutive exceedance durations are longer for sulphate aerosol than SO2, and can be particularly lengthy in the low air quality index levels (1-2 weeks), which may be of relevance to health impact assessments. This work represents a detailed initial study but has not explored the full range of such an eruption. Nonetheless, the results from this project are informing cross-Government work to improve the understanding of the risk to the UK from an effusive gas-rich eruption in Iceland. This includes the production of area-specific impact assessments for sectors including health, aviation and environment. "This work is distributed under the Creative Commons Attribution 3.0 Unported License together with an author copyright. This license does not conflict with the regulations of the Crown Copyright."

Persistent regional carbon dioxide anomalies driven by land use

NASA Astrophysics Data System (ADS)

Schultz, Colin

2012-04-01

Researchers have traditionally used measurements from remote locations, such as Hawaii's Mauna Loa Observatory and other isolated stations, to determine atmospheric carbon dioxide (CO2) concentrations and estimate the strengths of various carbon sources and sinks. The prevailing wisdom was that attempts to measure regional differences in CO2 over land would end up with signals that were either so small that they were undetectable or that were dominated by high-frequency variability due to atmospheric turbulence or weather. Measurements drawn from a moderately dense network of atmospheric gas composition sensors distributed across the upper midwestern United States, however, showed that large regional variations in tropospheric CO2 are readily observable. Drawing on measurements made at nine sensors spread over 400,000 square kilometers between 2007 and 2009, Miles et al. found that seasonal variations in atmospheric CO2 depend strongly on the type of ecosystem lying at the foot of each sensor tower.

Air quality status of an open pit mining area in India.

PubMed

Chaulya, S K

2005-06-01

This investigation presents the assessment of ambient air quality carried out at an open pit coal mining area in Orissa state of India. The 24-h average concentrations of suspended particulate matter (SPM), respirable particulate matter (RPM, particles of less than 10 microm aerodynamic diameter), sulphur dioxide (SO2) and oxides of nitrogen (NO(x)) were determined at regular interval throughout one year at 13 monitoring stations in residential area and four stations in mining/industrial area. During the study period, the 24-h and annual average SPM and RPM concentrations exceeded the respective standards set in the Indian ambient air quality standard (NAAQS) protocol in most of the residential and industrial areas. However, the 24-h and annual average concentrations of SO2 and NO(x) were well within the prescribed limit of the NAAQS in both residential and industrial areas. A management strategy is formulated for effective control of particulate matter at source and other mitigative measures are recommended including implementation of green belts around the sensitive areas.

40 CFR 52.1875 - Attainment dates for achieving the sulfur dioxide secondary standard.

Code of Federal Regulations, 2013 CFR

2013-07-01

... sulfur dioxide secondary standard. 52.1875 Section 52.1875 Protection of Environment ENVIRONMENTAL... (CONTINUED) Ohio § 52.1875 Attainment dates for achieving the sulfur dioxide secondary standard. The attainment date for achieving the sulfur dioxide (SO2) secondary national ambient air quality standard (NAAQS...

40 CFR 180.444 - Sulfur dioxide; tolerances for residues.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 40 Protection of Environment 24 2011-07-01 2011-07-01 false Sulfur dioxide; tolerances for... § 180.444 Sulfur dioxide; tolerances for residues. A tolerance is established as follows for sulfite residues of the fungicide sulfur dioxide (determined as (SO2)) in or on the following raw agricultural...

40 CFR 180.444 - Sulfur dioxide; tolerances for residues.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 40 Protection of Environment 25 2012-07-01 2012-07-01 false Sulfur dioxide; tolerances for... § 180.444 Sulfur dioxide; tolerances for residues. (a) General. A tolerance is established as follows for sulfite residues of the fungicide sulfur dioxide (determined as (SO2)) in or on the following raw...

40 CFR 52.1875 - Attainment dates for achieving the sulfur dioxide secondary standard.

Code of Federal Regulations, 2010 CFR

2010-07-01

... sulfur dioxide secondary standard. 52.1875 Section 52.1875 Protection of Environment ENVIRONMENTAL... (CONTINUED) Ohio § 52.1875 Attainment dates for achieving the sulfur dioxide secondary standard. The attainment date for achieving the sulfur dioxide (SO2) secondary national ambient air quality standard (NAAQS...

40 CFR 52.1875 - Attainment dates for achieving the sulfur dioxide secondary standard.

Code of Federal Regulations, 2011 CFR

2011-07-01

... sulfur dioxide secondary standard. 52.1875 Section 52.1875 Protection of Environment ENVIRONMENTAL... (CONTINUED) Ohio § 52.1875 Attainment dates for achieving the sulfur dioxide secondary standard. The attainment date for achieving the sulfur dioxide (SO2) secondary national ambient air quality standard (NAAQS...

40 CFR 52.1875 - Attainment dates for achieving the sulfur dioxide secondary standard.

Code of Federal Regulations, 2014 CFR

2014-07-01

... sulfur dioxide secondary standard. 52.1875 Section 52.1875 Protection of Environment ENVIRONMENTAL... (CONTINUED) Ohio § 52.1875 Attainment dates for achieving the sulfur dioxide secondary standard. The attainment date for achieving the sulfur dioxide (SO2) secondary national ambient air quality standard (NAAQS...

40 CFR 180.444 - Sulfur dioxide; tolerances for residues.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 40 Protection of Environment 25 2013-07-01 2013-07-01 false Sulfur dioxide; tolerances for... § 180.444 Sulfur dioxide; tolerances for residues. (a) General. A tolerance is established as follows for sulfite residues of the fungicide sulfur dioxide (determined as (SO2)) in or on the following raw...

40 CFR 180.444 - Sulfur dioxide; tolerances for residues.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 40 Protection of Environment 24 2014-07-01 2014-07-01 false Sulfur dioxide; tolerances for... § 180.444 Sulfur dioxide; tolerances for residues. (a) General. A tolerance is established as follows for sulfite residues of the fungicide sulfur dioxide (determined as (SO2)) in or on the following raw...

40 CFR 52.1875 - Attainment dates for achieving the sulfur dioxide secondary standard.

Code of Federal Regulations, 2012 CFR

2012-07-01

... sulfur dioxide secondary standard. 52.1875 Section 52.1875 Protection of Environment ENVIRONMENTAL... (CONTINUED) Ohio § 52.1875 Attainment dates for achieving the sulfur dioxide secondary standard. The attainment date for achieving the sulfur dioxide (SO2) secondary national ambient air quality standard (NAAQS...

40 CFR 180.444 - Sulfur dioxide; tolerances for residues.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 40 Protection of Environment 23 2010-07-01 2010-07-01 false Sulfur dioxide; tolerances for... § 180.444 Sulfur dioxide; tolerances for residues. A tolerance is established as follows for sulfite residues of the fungicide sulfur dioxide (determined as (SO2)) in or on the following raw agricultural...

Investigating a Sulphate-Nitrate Chemical Indirect Effect over Europe from 1980-2010

NASA Astrophysics Data System (ADS)

Pearce, H.; Mann, G. W.; Arnold, S.; O'Connor, F.; Conibear, L.; Turnock, S.; Rumbold, S.; Benduhn, F.

2017-12-01

Sulphur dioxide emission reductions have been successful in reducing surface sulphate concentrations over Europe between 1980 and 2010, with positive implications for air quality and human health. However the response of nitrate aerosol concentrations to declining NOx emissions has been non-linear. Previous studies have indicated that decreasing ammonium sulphate formation, as a result of SO2 emission reduction, may be partly responsible for this non-linearity by increasing the availability of ammonia and, hence, indirectly increasing ammonium nitrate aerosol formation. We use the UM-UKCA composition-climate model, including the GLOMAP interactive aerosol microphysics module and a recently developed `hybrid' dissolution solver (HyDis), to investigate the size-resolved partitioning of ammonia and nitric acid to the particle phase over Europe in the period 1980 to 2010. Anthropogenic emissions of SO2, NOx and NH3 are included from the MACCity inventory and change by approximately -79%, -33% and +30% respectively over Europe in this time. We evaluate the UM-UKCA simulated 1980-2010 variability in nitrate, ammonium and sulphate aerosol mass concentrations and aerosol pH, with comparison to EMEP observations, and isolate the indirect influence of reduced SO2 emissions on nitrate formation. Preliminary sensitivity tests indicate that simulated nitrate aerosol concentrations over Europe were 8% higher in 2009 than they would have been if SO2 emissions had not been reduced. The implications of this change for air quality, aerosol acidity and regional climate will be presented.

Analysis of air quality in Dire Dawa, Ethiopia.

PubMed

Kasim, Oluwasinaayomi Faith; Woldetisadik Abshare, Muluneh; Agbola, Samuel Babatunde

2017-12-07

Ambient air quality was monitored and analyzed to develop air quality index and its implications for livability and climate change in Dire Dawa, Ethiopia. Using survey research design, 16 georeferenced locations, representing different land uses, were randomly selected and assessed for sulfur dioxide (SO 2 ), nitrogen dioxide (NO 2 ), carbon dioxide (CO 2 ), carbon monoxide (CO),volatile organic compounds (VOCs), and meteorological parameters (temperature and relative humidity). The study found mean concentrations across all land uses for SO 2 of 0.37 ± 0.08 ppm, NO 2 of 0.13 ± 0.17 ppm, CO 2 of 465.65 ± 28.63 ppm, CO of 3.35 ± 2.04 ppm, and VOCs of 1850.67 ± 402 ppm. An air quality index indicated that ambient air quality for SO 2 was very poor, NO 2 ranged from moderate to very poor, whereas CO rating was moderate. Significant positive correlations existed between temperature and NO 2 , CO 2 , and CO and between humidity and VOCs. Significant relationships were also recorded between CO 2 and NO 2 and between CO and CO 2 . Poor urban planning, inadequate pollution control measure, and weak capacity to monitor air quality have implications for energy usage, air quality, and local meteorological parameters, with subsequent feedback into global climate change. Implementation of programs to monitor and control emissions in order to reduce air pollution will provide health, economic, and environmental benefits to the city. The need to develop and implement emission control programs to reduce air pollution in Dire Dawa City is urgent. This will provide enormous economic, health, and environmental benefits. It is expected that economic effects of air quality improvement will offset the expenditures for pollution control. Also, strategies that focus on air quality and climate change present a unique opportunity to engage different stakeholders in providing inclusive and sustainable development agenda for Dire Dawa.

The influence of deep-seabed CO2 sequestration on small metazoan (meiofaunal) viability and community structure: final technical report

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

Thistle, D

2008-09-30

Since the industrial revolution, the burning of fossil fuel has produced carbon dioxide at an increasing rate. Present atmospheric concentration is about ~1.5 times the preindustrial level and is rising. Because carbon dioxide is a greenhouse gas, its increased concentration in the atmosphere is thought to be a cause of global warming. If so, the rate of global warming could be slowed if industrial carbon dioxide were not released into the atmosphere. One suggestion has been to sequester it in the deep ocean, but theory predicts that deep-sea species will be intolerant of the increased concentrations of carbon dioxide andmore » the increased acidity it would cause. The aim of our research was to test for consequences of carbon dioxide sequestration on deep-sea, sediment-dwelling meiofauna. Recent technical advances allowed us to test for effects in situ at depths proposed for sequestration. The basic experimental unit was an open-topped container into which we pumped ~20 L of liquid carbon dioxide. The liquid carbon dioxide mixed with near-bottom sea water, which produced carbon dioxide-rich sea water that flowed out over the near-by seabed. We did 30-day experiments at several locations and with different numbers of carbon dioxide-filled containers. Harpacticoid copepods (Crustacea) were our test taxon. In an experiment we did during a previous grant period, we found that large numbers of individuals exposed to carbon dioxide-rich sea water had been killed (Thistle et al. 2004). During the present grant period, we analyzed the species-level data in greater detail and discovered that, although individuals of many species had been killed by exposure to carbon dioxide-rich sea water, individuals of some species had not (Thistle et al. 2005). This result suggests that seabed sequestration of carbon dioxide will not just reduce the abundance of the meiofauna but will change the composition of the community. In another experiment, we found that some harpacticoid species swim away from an advancing front of carbon dioxide-rich sea water (Thistle et al. 2007). This result demonstrates a second way that deep-sea meiofauna react negatively to carbon dioxide-rich sea water. In summary, we used in situ experiments to show that carbon dioxide-rich sea water triggers an escape response in some harpacticoid species. It kills most individuals of most harpacticoid species that do not flee, but a few species seem to be unaffected. Proposals to reduce global warming by sequestering industrial carbon dioxide in the deep ocean should take note of these environmental consequences when pros and cons are weighed.« less

Role of Southern Ocean stratification in glacial atmospheric CO2 reduction

NASA Astrophysics Data System (ADS)

Kobayashi, H.; Oka, A.

2014-12-01

Paleoclimate proxy data at the glacial period shows high salinity of more than 37.0 psu in the deep South Atlantic. At the same time, data also indicate that the residence time of the water mass was more than 3000 years. These data implies that the stratification by salinity was stronger in the deep Southern Ocean (SO) in the Last Glacial Maximum (LGM). Previous studies using Ocean General Circulation Model (OGCM) fail to explain the low glacial atmospheric carbon dioxide (CO2) concentration at LGM. The reproducibility of salinity and water mass age is considered insufficient in these OGCMs, which may in turn affect the reproducibility of the atmospheric CO2concentration. In coarse-resolution OGCMs, The deep water is formed by unrealistic open-ocean deep convection in the SO. Considering these facts, we guessed previous studies using OGCM underestimated the salinity and water mass age at LGM. This study investigate the role of the enhanced stratification in the glacial SO on the variation of atmospheric CO2 concentration by using OGCM. In order to reproduce the recorded salinity of the deep water, relaxation of salinity toward value of recorded data is introduced in our OGCM simulations. It was found that deep water formation in East Antarctica is required for explaining the high salinity in the South Atlantic. In contrast, it is difficult to explain the glacial water mass age, even if we assume the situation vertical mixing is very weak in the SO. Contrary to previous estimate, the high salinity of the deep SO resulted in increase of Antarctic Bottom water (AABW) flow and decrease the residence time of carbon in the deep ocean, which increased atmospheric CO2 concentration. On the other hand, the weakening of the vertical mixing in the SO contributed to increase the vertical gradient of dissolved inorganic carbon (DIC), which decreased atmospheric CO2 concentration. Adding the contribution of the enhanced stratification in the glacial SO, we obtained larger reduction in atmospheric CO2 concentration than previous studies. However, we still fail to explain the full amplitude of recorded glacial reduction of atmospheric CO2 concentration. The carbonate compensation process, which is not incorporated in our simulations, might be required for further reduction in atmospheric CO2 concentration.

Atmospheric sulfur cycling in the southeastern Pacific - longitudinal distribution, vertical profile, and diel variability observed during VOCALS-REx

NASA Astrophysics Data System (ADS)

Yang, M.; Huebert, B. J.; Blomquist, B. W.; Howell, S. G.; Shank, L. M.; McNaughton, C. S.; Clarke, A. D.; Hawkins, L. N.; Russell, L. M.; Covert, D. S.; Coffman, D. J.; Bates, T. S.; Quinn, P. K.; Zagorac, N.; Bandy, A. R.; de Szoeke, S. P.; Zuidema, P. D.; Tucker, S. C.; Brewer, W. A.; Benedict, K. B.; Collett, J. L.

2011-05-01

Dimethylsulfide (DMS) emitted from the ocean is a biogenic precursor gas for sulfur dioxide (SO2) and non-sea-salt sulfate aerosols (SO42-). During the VAMOS-Ocean-Cloud-Atmosphere-Land Study Regional Experiment (VOCALS-REx) in 2008, multiple instrumented platforms were deployed in the Southeastern Pacific (SEP) off the coast of Chile and Peru to study the linkage between aerosols and stratocumulus clouds. We present here observations from the NOAA Ship Ronald H. Brown and the NSF/NCAR C-130 aircraft along ~20° S from the coast (70° W) to a remote marine atmosphere (85° W). While SO42- and SO2 concentrations were distinctly elevated above background levels in the coastal marine boundary layer (MBL) due to anthropogenic influence (~800 and 80 pptv, respectively), their concentrations rapidly decreased west of 78° W (~100 and 25 pptv). In the remote region, entrainment from the free troposphere (FT) increased MBL SO2 burden at a rate of 0.05 ± 0.02 μmoles m-2 day-1 and diluted MBL SO42 burden at a rate of 0.5 ± 0.3 μmoles m-2 day-1, while the sea-to-air DMS flux (3.8 ± 0.4 μmoles m-2 day-1) remained the predominant source of sulfur mass to the MBL. In-cloud oxidation was found to be the most important mechanism for SO2 removal and in situ SO42- production. Surface SO42- concentration in the remote MBL displayed pronounced diel variability, increasing rapidly in the first few hours after sunset and decaying for the rest of the day. We theorize that the increase in SO42- was due to nighttime recoupling of the MBL that mixed down cloud-processed air, while decoupling and sporadic precipitation scavenging were responsible for the daytime decline in SO42-.

Infrared Hollow Optical Fiber Probe for Localized Carbon Dioxide Measurement in Respiratory Tracts

PubMed Central

Katagiri, Takashi; Shibayama, Kyosuke; Iida, Takeru

2018-01-01

A real-time gas monitoring system based on optical absorption spectroscopy is proposed for localized carbon dioxide (CO2) measurement in respiratory tracts. In this system, a small gas cell is attached to the end of a hollow optical fiber that delivers mid-infrared light with small transmission loss. The diameters of the fiber and the gas cell are smaller than 1.2 mm so that the probe can be inserted into a working channel of common bronchoscopes. The dimensions of the gas cell are designed based on absorption spectra of CO2 standard gases in the 4.2 μm wavelength region, which are measured using a Fourier-transform infrared spectrometer. A miniature gas cell that is comprised of a stainless-steel tube with slots for gas inlet and a micro-mirror is fabricated. A compact probing system with a quantum cascade laser (QCL) light source is built using a gas cell with a hollow optical fiber for monitoring CO2 concentration. Experimental results using human breaths show the feasibility of the system for in-situ measurement of localized CO2 concentration in human airways. PMID:29584666

Associations Between Ultrafine Particles and Co-Pollutant Concentrations in the Tampa Bay Area.

PubMed

Desai, Ushang; Watson, Alain

2016-05-01

Ultrafine particles (UFPs) are ubiquitous in urban air and have been recognized as a risk to human health. The aim of this study was to measure the relationships among ultrafine particles and other ambient air pollutants and meteorological factors in the Tampa Bay Area. This study measured continuous UFPs, black carbon, oxides of nitrogen (NO(x)), nitrogen dioxide (NO2), nitric oxide (NO), carbon monoxide (CO), ozone (O3), sulfur dioxide (SO2), particulate matter having an aerodynamic diameter of 10 microns or less (PM10), relative humidity, wind speed, and ambient temperature during January to March 2014. Moreover, the study compared the relationship between UFPs and various co-pollutants daily, including during morning rush hour periods. This study found a moderate correlation among UFPs and black carbon, NO(x), NO2, and NO during hourly continuous measurements and rush hour periods, and a low level of correlation among UFPs and CO, O3, SO2, PM10, relative humidity, wind speed, and ambient temperature. This study indicates that co-pollutants should not be used as a surrogate to assess the human health risk from ultrafine particles exposure.

Predicting decadal trends in cloud droplet number concentration using reanalysis and satellite data

NASA Astrophysics Data System (ADS)

McCoy, Daniel T.; Bender, Frida A.-M.; Grosvenor, Daniel P.; Mohrmann, Johannes K.; Hartmann, Dennis L.; Wood, Robert; Field, Paul R.

2018-02-01

Cloud droplet number concentration (CDNC) is the key state variable that moderates the relationship between aerosol and the radiative forcing arising from aerosol-cloud interactions. Uncertainty related to the effect of anthropogenic aerosol on cloud properties represents the largest uncertainty in total anthropogenic radiative forcing. Here we show that regionally averaged time series of the Moderate-Resolution Imaging Spectroradiometer (MODIS) observed CDNC of low, liquid-topped clouds is well predicted by the MERRA2 reanalysis near-surface sulfate mass concentration over decadal timescales. A multiple linear regression between MERRA2 reanalyses masses of sulfate (SO4), black carbon (BC), organic carbon (OC), sea salt (SS), and dust (DU) shows that CDNC across many different regimes can be reproduced by a simple power-law fit to near-surface SO4, with smaller contributions from BC, OC, SS, and DU. This confirms previous work using a less sophisticated retrieval of CDNC on monthly timescales. The analysis is supported by an examination of remotely sensed sulfur dioxide (SO2) over maritime volcanoes and the east coasts of North America and Asia, revealing that maritime CDNC responds to changes in SO2 as observed by the ozone monitoring instrument (OMI). This investigation of aerosol reanalysis and top-down remote-sensing observations reveals that emission controls in Asia and North America have decreased CDNC in their maritime outflow on a decadal timescale.

Optoacoustic Determination of Carbon Dioxide Concentration in Exhaled Breath in Various Human Diseases*

NASA Astrophysics Data System (ADS)

Ageev, V. G.; Nikiforova, O. Yu.

2016-11-01

We determined the carbon dioxide concentrations in exhaled breath from healthy donors and patients with various diseases from the absorption spectra of test samples, recorded on a laser optoacoustic gas analyzer based on a CO2 laser. We observed that the carbon dioxide concentrations in exhaled breath from healthy donors is higher than in patients with various diseases.

Formation of secondary aerosols from gasoline vehicle exhausts when mixing with SO2

NASA Astrophysics Data System (ADS)

Liu, T.; Wang, X.; Hu, Q.; Deng, W.; Zhang, Y.; Ding, X.; Fu, X.; Bernard, F.; Zhang, Z.; Lü, S.; He, Q.; Bi, X.; Chen, J.; Sun, Y.; Yu, J.; Peng, P.; Sheng, G.; Fu, J.

2015-09-01

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 exhausts, is still poorly understood. Here we directly co-introduced gasoline vehicles exhausts (GVE) and SO2, a typical pollutant from coal burning, into a smog chamber to investigate the formation of secondary organic aerosols (SOA) and sulfate aerosols through photooxidation. In the presence of high concentration of SO2, new particle formation was enhanced while substantial sulfate was formed through the oxidation of SO2. The 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. This increase could largely be attributed to acid-catalyzed SOA formation, which was evidenced by the strong positive linear correlation (R2 = 0.97) between the SOA production factor and in-situ particle acidity calculated by 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) and higher hydrogen-to-carbon (H : C) molar ratios for the GVE/SO2 mixture, with a much lower estimated average carbon oxidation state (OSc) of -0.51 ± 0.06 than that of -0.19 ± 0.08 for GVE alone. The relative higher mass loading of OA in the experiments with SO2 might be the major reason for the lower oxidation degree of SOA.

[Study of the Detecting System of CH4 and SO2 Based on Spectral Absorption Method and UV Fluorescence Method].

PubMed

Wang, Shu-tao; Wang, Zhi-fang; Liu, Ming-hua; Wei, Meng; Chen, Dong-ying; Wang, Xing-long

2016-01-01

According to the spectral absorption characteristics of polluting gases and fluorescence characteristics, a time-division multiplexing detection system is designed. Through this system we can detect Methane (CH4) and sulfur dioxide (SO2) by using spectral absorption method and the SO2 can be detected by using UV fluorescence method. The system consists of four parts: a combination of a light source which could be switched, the common optical path, the air chamber and the signal processing section. The spectral absorption characteristics and fluorescence characteristics are measured first. Then the experiment of detecting CH4 and SO2 through spectral absorption method and the experiment of detecting SO2 through UV fluorescence method are conducted, respectively. Through measuring characteristics of spectral absorption and fluorescence, we get excitation wavelengths of SO2 and CH4 measured by spectral absorption method at the absorption peak are 280 nm and 1.64 μm, respectively, and the optimal excitation wavelength of SO2 measured by UV fluorescence method is 220 nm. we acquire the linear relation between the concentration of CH4 and relative intensity and the linear relation between the concentration of SO2 and output voltage after conducting the experiment of spectral absorption method, and the linearity are 98.7%, 99.2% respectively. Through the experiment of UV fluorescence method we acquire that the relation between the concentration of SO2 and the voltage is linear, and the linearity is 99.5%. Research shows that the system is able to be applied to detect the polluted gas by absorption spectrum method and UV fluorescence method. Combing these two measurement methods decreases the costing and the volume, and this system can also be used to measure the other gases. Such system has a certain value of application.

Adsorption of sulfur dioxide on ammonia-treated activated carbon fibers

USGS Publications Warehouse

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

2001-01-01

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

Folded tubular photometer for atmospheric measurements of NO2 and NO

NASA Astrophysics Data System (ADS)

Birks, John W.; Andersen, Peter C.; Williford, Craig J.; Turnipseed, Andrew A.; Strunk, Stanley E.; Ennis, Christine A.; Mattson, Erick

2018-05-01

We describe and characterize a modular folded tubular photometer for making direct measurements of the concentrations of nitrogen dioxide (NO2) and specify how this method could be extended to measure other pollutants such as sulfur dioxide (SO2), ozone (O3), and black carbon particulate matter. Direct absorbance measurements using this photometer can be made across the spectral range from the ultraviolet (UV) to the near infrared. The absorbance cell makes use of modular components (tubular detection cells and mirror cubes) that allow construction of path lengths of up to 2 m or more while maintaining low cell volumes. The long path lengths and low cell volumes enable sensitive detection of ambient air pollutants down to low part-per-billion levels for gas species and aerosol extinctions down to 1 Mm-1, corresponding to ˜ 0.1 µg m-3 for black carbon particulates. Pressure equalization throughout the stages of the absorbance measurement is shown to be critical to accurate measurements of analyte concentrations. The present paper describes the application of this photometer to direct measurements of nitrogen dioxide (NO2) and the incorporation of design features that also enable measurement of nitric oxide (NO) in the same instrument. Excellent agreement for ambient measurements along an urban roadside was found for both NO2 and NO measured by the folded tubular photometer compared to existing standard techniques. Compared to commonly used methods for measurements of NOx species, the advantages of this approach include (1) an absolute quantification for NO2 based on the Beer-Lambert law, thereby greatly reducing the frequency at which calibrations are required; (2) the direct measurement of NO2 concentration without prior conversion to NO as is required for the commonly used chemiluminescence method; (3) the use of modular components that allow construction of absorbance detection cells of varying lengths for extending the dynamic range of concentrations that can be measured; (4) a more economical instrument than other currently available direct measurement techniques for NO2; and (5) the potential for simultaneous detection of additional species such as SO2, O3, and black carbon in the same instrument. In contrast to other commercially available direct NO2 measurements, such as cavity-attenuated phase-shift spectroscopy (CAPS), the folded tubular photometer also measures NO simultaneously in the same apparatus by quantitatively converting NO to NO2 with ozone, which is then detected by direct absorbance.

Concentration-dependence of the explosion characteristics of chlorine dioxide gas.

PubMed

Jin, Ri-ya; Hu, Shuang-qi; Zhang, Yin-ghao; Bo, Tao

2009-07-30

The explosion characteristics of chlorine dioxide gas have been studied for the first time in a cylindrical exploder with a shell capacity of 20 L. The experimental results have indicated that the lower concentration limit for the explosive decomposition of chlorine dioxide gas is 9.5% ([ClO(2)]/[air]), whereas there is no corresponding upper concentration limit. Under the experimental conditions, and within the explosion limits, the pressure of explosion increases with increasing concentration of chlorine dioxide gas; the maximum pressure of explosion relative to the initial pressure was measured as 0.024 MPa at 10% ClO(2) and 0.641 MPa at 90% ClO(2). The induction time (the time from the moment of sparking to explosion) has also been found to depend on the concentration of chlorine dioxide gas; thus, at 10% ClO(2) the induction time was 2195 ms, but at 90% ClO(2) the induction time was just 8 ms. The explosion reaction mechanism of ClO(2) is of a degenerate chain-branching type involving the formation of a stable intermediate (Cl(2)O(3)), from which the chain-branching occurs. Chain initiation takes place at the point of ignition and termination takes place at the inner walls of the exploder.

Application of Weather Research and Forecasting Model with Chemistry (WRF/Chem) over northern China: Sensitivity study, comparative evaluation, and policy implications

NASA Astrophysics Data System (ADS)

Wang, Litao; Zhang, Yang; Wang, Kai; Zheng, Bo; Zhang, Qiang; Wei, Wei

2016-01-01

An extremely severe and persistent haze event occurred over the middle and eastern China in January 2013, with the record-breaking high concentrations of fine particulate matter (PM2.5). In this study, an online-coupled meteorology-air quality model, the Weather Research and Forecasting Model with Chemistry (WRF/Chem), is applied to simulate this pollution episode over East Asia and northern China at 36- and 12-km grid resolutions. A number of simulations are conducted to examine the sensitivities of the model predictions to various physical schemes. The results show that all simulations give similar predictions for temperature, wind speed, wind direction, and humidity, but large variations exist in the prediction for precipitation. The concentrations of PM2.5, particulate matter with aerodynamic diameter of 10 μm or less (PM10), sulfur dioxide (SO2), and nitrogen dioxide (NO2) are overpredicted partially due to the lack of wet scavenging by the chemistry-aerosol option with the 1999 version of the Statewide Air Pollution Research Center (SAPRC-99) mechanism with the Model for Simulating Aerosol Interactions and Chemistry (MOSAIC) and the Volatility Basis Set (VBS) for secondary organic aerosol formation. The optimal set of configurations with the best performance is the simulation with the Gorddard shortwave and RRTM longwave radiation schemes, the Purdue Lin microphysics scheme, the Kain-Fritsch cumulus scheme, and a nudging coefficient of 1 × 10-5 for water vapor mixing ratio. The emission sensitivity simulations show that the PM2.5 concentrations are most sensitive to nitrogen oxide (NOx) and SO2 emissions in northern China, but to NOx and ammonia (NH3) emissions in southern China. 30% NOx emission reductions may result in an increase in PM2.5 concentrations in northern China because of the NH3-rich and volatile organic compound (VOC) limited conditions over this area. VOC emission reductions will lead to a decrease in PM2.5 concentrations in eastern China. However, 30% reductions in the emissions of SO2, NOx, NH3, and VOC, individually or collectively, are insufficient to effectively mitigate the severe pollution over northern China. More aggressive emission controls, which needs to be identified in further studies, are needed in this area to reach the objective of 25% PM2.5 concentration reduction in 2017 proposed in the Action Plan for Air Pollution Prevention and Control by the State Council in 2013.

Activation and thermostabilization effects of cyclic 2, 3-diphosphoglycerate on enzymes from the hyperthermophilic Methanopyrus kandleri.

PubMed

Shima, S; Hérault, D A; Berkessel, A; Thauer, R K

1998-11-01

Enzymes involved in methane formation from carbon dioxide and dihydrogen in Methanopyrus kandleri require high concentrations (> 1 M) of lyotropic salts such as K2HPO4/KH2PO4 or (NH4)2SO4 for activity and for thermostability. The requirement correlates with high intracellular concentrations of cyclic 2,3-diphosphoglycerate (cDPG; approximately 1 M) in this hyperthermophilic organism. We report here on the effects of potassium cDPG on the activity and thermostability of the two methanogenic enzymes cyclohydrolase and formyltransferase and show that at cDPG concentrations prevailing in the cells the investigated enzymes are highly active and completely thermostable. At molar concentrations also the potassium salts of phosphate and of 2,3-bisphosphoglycerate, the biosynthetic precursor of cDPG, were found to confer activity and thermostability to the enzymes. Thermodynamic arguments are discussed as to why cDPG, rather than these salts, is present in high concentrations in the cells of Mp. kandleri.

Temporal variability of air-pollutants over Abu Dhabi, UAE

NASA Astrophysics Data System (ADS)

Ghedira, H.; Ben Romdhane, H.; Beegum S, N.

2013-12-01

Air quality, the measure of the concentrations of gaseous pollutants and size or number of particulate matter, is one of the most important problems worldwide and has strong implications on human health, ecosystems, as well as regional and global climate. The levels of air pollutants such as sulphur dioxide (SO2), particulate matters (PM10, PM2.5), Ozone (O3), Nitrogen dioxide (NO2), Carbon monoxide (CO), etc. show an alarming increase in urban cities across the world and in many cases, the concentrations have grown well above the World Health Organization's guidelines for ambient air-quality standards. Here, we present the periodic fluctuations observed in the concentrations of air pollutants such as SO2, NO2, O3, CO, H2S, NMHC (Non methane Hydro Carbon) and VOC (volatile organic compounds) based on the measurements collected during the period 2008-2010 at Masdar City, Abu Dhabi (24.42oN, 54.61oE, 7m MSL). The measurements were carried out using an Air Quality Monitoring System (AQM60). All these pollutant species showed statistical periodic: diurnal, monthly, seasonal and annual variations. Diurnally, all the species, except ozone, depicted an afternoon low and nighttime/early morning high, attributed to the dynamics of the local atmospheric boundary layer. Whereas, an opposite pattern with daytime high and nighttime low was observed for O3, as the species is formed in the troposphere by catalytic photochemical reactions of NOx with CO, CH4 and other VOCs. Seasonally, the pollutants depicted higher values during summer and relatively lower values during winter, associated with changes in synoptic airmass types and/or removal processes. Concentrations of all the gaseous pollutants are within the National Ambient Air Quality Standards (NAAQS) throughout the year, whereas the PM10 often exceeded the limits, especially during dust storm episodes.

Air quality assessment in Delhi: before and after CNG as fuel.

PubMed

Chelani, Asha B; Devotta, Sukumar

2007-02-01

A number of policy measures have been activated in India in order to control the levels of air pollutants such as particulate matter, sulphur dioxide (SO(2)) and nitrogen dioxide (NO(2)). Delhi, which is one of the most polluted cities in the world, is also going through the implementation phase of the control policies. Ambient air quality data monitored during 2000 to 2003, at 10 sites in Delhi, were analyzed to assess the impact of implementation of these measures, specifically fuel change in vehicles. This paper presents the impact of policy measures on ambient air quality levels and also the source apportionment. CO and NO(2) concentration levels in ambient air are found to be associated with the mobile sources. The temporal variation of air quality data shows the significant effect of shift to CNG (Compressed Natural Gas) in vehicles.

78 FR 28143 - Approval and Promulgation of Air Quality Implementation Plans; Indiana; Sulfur Dioxide and...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-05-14

...-9811-6] Approval and Promulgation of Air Quality Implementation Plans; Indiana; Sulfur Dioxide and Nitrogen Dioxide Ambient Air Quality Standards AGENCY: Environmental Protection Agency (EPA). ACTION... amend the national ambient air quality standards (NAAQS) for NO 2 and SO 2 to be consistent with the...

STATUS OF SO2 SCRUBBING TECHNOLOGIES

EPA Science Inventory

The paper presents the extent of current sulfur dioxide (SO2) scrubber applications on electricity generating units in the U.S. and abroad. The technical performance of recent SO2 scrubber installations is discussed. Recently reported technical innovations to SO2 scrubbing tech...

Time-series analyses of air pollution and mortality in the United States: a subsampling approach.

PubMed

Moolgavkar, Suresh H; McClellan, Roger O; Dewanji, Anup; Turim, Jay; Luebeck, E Georg; Edwards, Melanie

2013-01-01

Hierarchical Bayesian methods have been used in previous papers to estimate national mean effects of air pollutants on daily deaths in time-series analyses. We obtained maximum likelihood estimates of the common national effects of the criteria pollutants on mortality based on time-series data from ≤ 108 metropolitan areas in the United States. We used a subsampling bootstrap procedure to obtain the maximum likelihood estimates and confidence bounds for common national effects of the criteria pollutants, as measured by the percentage increase in daily mortality associated with a unit increase in daily 24-hr mean pollutant concentration on the previous day, while controlling for weather and temporal trends. We considered five pollutants [PM10, ozone (O3), carbon monoxide (CO), nitrogen dioxide (NO2), and sulfur dioxide (SO2)] in single- and multipollutant analyses. Flexible ambient concentration-response models for the pollutant effects were considered as well. We performed limited sensitivity analyses with different degrees of freedom for time trends. In single-pollutant models, we observed significant associations of daily deaths with all pollutants. The O3 coefficient was highly sensitive to the degree of smoothing of time trends. Among the gases, SO2 and NO2 were most strongly associated with mortality. The flexible ambient concentration-response curve for O3 showed evidence of nonlinearity and a threshold at about 30 ppb. Differences between the results of our analyses and those reported from using the Bayesian approach suggest that estimates of the quantitative impact of pollutants depend on the choice of statistical approach, although results are not directly comparable because they are based on different data. In addition, the estimate of the O3-mortality coefficient depends on the amount of smoothing of time trends.

[Study on pipe material's influence on chlorine dioxide drinking water disinfection].

PubMed

He, Tao; Yue, Yinling; Ling, Bo; Zhang, Lan

2010-09-01

To study the pipe material's influence on chlorine dioxide drinking water disinfection. 0.8 mg/L chlorine dioxide solution was injected into 5 kinds of pipes respectively, PPR, PVC-U, Steel with Zinc coating, copper and PE pipes. Dipped free from light for 48 hours and the concentrations of chlorine dioxide, chlorite and chlorate were tested from samples taken from each kind of pipe at 1, 2, 3, 4, 5, 6, 12, 24 and 48 hours respectively. Chlorine dioxides decay rates in the water dipping the pipes increase as the dipping time increases and the decay of chlorine dioxide mainly occurs within 6 hours after the dipping. But for different pipe, the influence of decay differs. The consumption of chlorine dioxide of the metal pipes is more than that of the plastic pipes. And with 2 hours after the dipping experiment begins, the concentrations of the chlorite of the copper pipe and of the steel with zinc coating pipe increase quickly and reach the maximum concentration. But then the chlorite concentration decreases greatly. After dipped 24 hours, the chlorite in the water in the pipe can not be detected. For other plastic piples, all the chlorite concentrations in the dipping water increase as the dipping time increase. Compared with the start of the dipping experiment, the chlorate concentration in the dipping water of each pipe has no obvious change. The material of the water transportation pipe does have influence on chlorine dioxide drinking water disinfection.

Assessment of the UV camera sulfur dioxide retrieval for point source plumes

USGS Publications Warehouse

Dalton, M.P.; Watson, I.M.; Nadeau, P.A.; Werner, C.; Morrow, W.; Shannon, J.M.

2009-01-01

Digital cameras, sensitive to specific regions of the ultra-violet (UV) spectrum, have been employed for quantifying sulfur dioxide (SO2) emissions in recent years. The instruments make use of the selective absorption of UV light by SO2 molecules to determine pathlength concentration. Many monitoring advantages are gained by using this technique, but the accuracy and limitations have not been thoroughly investigated. The effect of some user-controlled parameters, including image exposure duration, the diameter of the lens aperture, the frequency of calibration cell imaging, and the use of the single or paired bandpass filters, have not yet been addressed. In order to clarify methodological consequences and quantify accuracy, laboratory and field experiments were conducted. Images were collected of calibration cells under varying observational conditions, and our conclusions provide guidance for enhanced image collection. Results indicate that the calibration cell response is reliably linear below 1500 ppm m, but that the response is significantly affected by changing light conditions. Exposure durations that produced maximum image digital numbers above 32 500 counts can reduce noise in plume images. Sulfur dioxide retrieval results from a coal-fired power plant plume were compared to direct sampling measurements and the results indicate that the accuracy of the UV camera retrieval method is within the range of current spectrometric methods. ?? 2009 Elsevier B.V.

Simulating the propagation of sulphur dioxide emissions from the fissure eruption in the Holuhraun lava field (Iceland) with the EURAD-IM

NASA Astrophysics Data System (ADS)

Fröhlich, Luise; Franke, Philipp; Friese, Elmar; Haas, Sarah; Lange, Anne Caroline; Elbern, Hendrik

2015-04-01

In the emergency case of a volcano eruption accurate forecasts of the transport of ash and gas emissions are crucial for health protection and aviation safety. In the frame of Earth System Knowledge Platform (ESKP) near real-time forecasts of ash and SO2 dispersion emitted by active volcanoes are simulated by the European Air pollution Dispersion Inverse Model (EURAD-IM). The model is driven by the Weather Research and Forecasting Model (WRF) and includes detailed gas phase and particle dynamics modules, which allow for quantitative estimates of measured volcano releases. Former simulations, for example related to the Eyjafjallajökull outbreak in 2010, were in good agreement with measurement records of particle number and SO2 at several European stations. At the end of August 2014 an fissure eruption has begun on Iceland in the Holuhraun lava field to the north-east of the Bardarbunga volcano system. In contrast to the explosive eruption of the Eyjafjallajökull in 2010, the Holuhraun eruption is rather effusive with a large and continuous flow of lava and a significant release of sulphur dioxide (SO2) in the lower troposphere, while ash emissions are insignificant. Since the Holuhraun fissure eruption has started, daily forecasts of SO2 dispersion are produced for the European region (15 km horizontal resolution grid) and published on our website (http://apps.fz-juelich.de/iek-8/RIU/vorhersage_node.php). To simulate the transport of volcanic emissions, realistic source terms like mass release rates of ash and SO2 or plume heights are required. Since no representative measurements are currently available for the simulations, rough qualitative assumptions, based on reports from the Icelandic Met Office (IMO), are used. However, frequent comparisons with satellite observations show that the actual propagation of the volcanic emissions is generally well reflected by the model. In the middle of September 2014 several European measurement sides recorded extremely high SO2 concentrations at ground level which were predicted quite accurately in advance by the EURAD-IM. Further more, the simulations indicate that the unusual high SO2 values are due to the transport of sulphur dioxide rich air from the Bardarbunga towards continental Europe. Presently, SO2 dispersion forecasts are also conducted on a finer spatial resolution grid (1 km) for the Icelandic region. These simulations will be validated against measurements from different observation sides in Iceland.

Atmospheric sulfur cycling in the Southeastern Pacific - longitudinal distribution, vertical profile, and diel variability observed during VOCALS-REx

NASA Astrophysics Data System (ADS)

Yang, M.; Huebert, B. J.; Blomquist, B. W.; Howell, S. G.; Shank, L. M.; McNaughton, C. S.; Clarke, A. D.; Hawkins, L. N.; Russell, L. M.; Covert, D. S.; Coffman, D. J.; Bates, T. S.; Quinn, P. K.; Zagorac, N.; Bandy, A. R.; de Szoeke, S. P.; Zuidema, P. D.; Tucker, S. C.; Brewer, W. A.; Benedict, K. B.; Collett, J. L.

2011-01-01

Dimethylsulfide (DMS) emitted from the ocean is a biogenic precursor gas for sulfur dioxide (SO2) and non-sea-salt sulfate aerosols (SO42). During the VAMOS-Ocean-Cloud-Atmosphere-Land Study Regional Experiment (VOCALS-REx) in 2008, multiple instrumented platforms were deployed in the Southeastern Pacific (SEP) off the coast of Chile and Peru to study the linkage between aerosols and stratocumulus clouds. We present here observations from the NOAA Ship Ronald H. Brown and the NSF/NCAR C-130 aircraft along ~20° S from the coast (70° W) to a remote marine region (85° W). While SO42- and SO2 concentrations were distinctly elevated above background levels in the coastal marine boundary layer (MBL) due to anthropogenic influence (~800 and 80 pptv, respectively), their concentrations rapidly decreased offshore (~100and 25 pptv). Compared to the "mass" entrainment fluxes of SO42- and SO2 from the free troposphere (0.5 ± 0.3 and 0.3 ± 0.2 μmoles m-2 day-1), the sea-to-air DMS flux (3.8 ± 0.1 μmoles m-2 day-1) remained the predominant source of sulfur mass to the MBL. In-cloud oxidation was found to be the most important mechanism for SO2 removal and in situ SO42- production. Surface SO42- loading in the remote region displayed pronounced diel variability, increasing rapidly in the first few hours after sunset and then decaying for the rest of the time. We theorize that the increase in SO42- was due to nighttime recoupling of the MBL that mixed down cloud-processed air, while decoupling and sporadic precipitation scavenging were responsible for the daytime decline in SO42-.

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

Shertz, R.D.; Kender, W.J.; Musselman, R.C.

Three cultivars of greenhouse-grown apple trees (Malus domestica, Borkh.) were fumigated for single, 4-hour exposures with ozone (O/sub 3/) and/or sulfur dioxide (SO/sub 2/) at 0.40 and 0.80 ppm. Fumigations were performed in a plexiglass chamber situated within a controlled environment walk-in growth chamber. All 3 cultivars responded to treatments in a similar manner. When applied separately both gases induced characteristic foliar injury. In general, apple trees were more sensitive to 0.40 ppm O/sub 3/ than to 0.40 ppm SO/sub 2/; but they responded similarly to 0.80 ppm O/sub 3/ or SO/sub 2/. Foliar injury, leaf abscission, and shoot growthmore » reduction were greatest when 0.80 ppm O/sub 3/ and 0.80 ppm SO/sub 2/ were combined. The data showed a less-than additive response when the 2 pollutants were combined; a response due, in part, to the high amount of injury induced by single pollutants at these concentrations. All O/sub 3/ and/or SO/sub 2/ fumigations resulted in stomatal closure.« less

Mortality Associations with Long-Term Exposure to Outdoor Air Pollution in a National English Cohort

PubMed Central

Carey, Iain M.; Kent, Andrew J.; van Staa, Tjeerd; Cook, Derek G.; Anderson, H. Ross

2013-01-01

Rationale: Cohort evidence linking long-term exposure to outdoor particulate air pollution and mortality has come largely from the United States. There is relatively little evidence from nationally representative cohorts in other countries. Objectives: To investigate the relationship between long-term exposure to a range of pollutants and causes of death in a national English cohort. Methods: A total of 835,607 patients aged 40–89 years registered with 205 general practices were followed from 2003–2007. Annual average concentrations in 2002 for particulate matter with a median aerodynamic diameter less than 10 (PM10) and less than 2.5 μm (PM2.5), nitrogen dioxide (NO2), ozone, and sulfur dioxide (SO2) at 1 km2 resolution, estimated from emission-based models, were linked to residential postcode. Deaths (n = 83,103) were ascertained from linkage to death certificates, and hazard ratios (HRs) for all- and cause-specific mortality for pollutants were estimated for interquartile pollutant changes from Cox models adjusting for age, sex, smoking, body mass index, and area-level socioeconomic status markers. Measurements and Main Results: Residential concentrations of all pollutants except ozone were positively associated with all-cause mortality (HR, 1.02, 1.03, and 1.04 for PM2.5, NO2, and SO2, respectively). Associations for PM2.5, NO2, and SO2 were larger for respiratory deaths (HR, 1.09 each) and lung cancer (HR, 1.02, 1.06, and 1.05) but nearer unity for cardiovascular deaths (1.00, 1.00, and 1.04). Conclusions: These results strengthen the evidence linking long-term ambient air pollution exposure to increased all-cause mortality. However, the stronger associations with respiratory mortality are not consistent with most US studies in which associations with cardiovascular causes of death tend to predominate. PMID:23590261

Sulfur dioxide-hydrogen peroxide relationships in clean air, clouds, and precipitation

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

Schwartz, S.E.; Daum, P.H.

1988-01-01

In-cloud oxidation by H/sub 2/O/sub 2/ is a major route for conversion of atmospheric SO/sub 2/ to sulfate, as indicated by kinetic calculations for representative H/sub 2/O/sub 2/ concentrations and supported by the observation of mutual exclusivity of gaseous SO/sub 2/ and aqueous H/sub 2/O/sub 2/ in non-precipitating liquid-water stratiform clouds, which generally persist sufficiently for reaction to proceed to completion. Measurements reported here indicate the aqueous S(IV) and H/sub 2/O/sub 2/ are also mutually exclusive in surface precipitation samples, but that SO/sub 2/ and aqueous H/sub 2/O/sub 2/ often coexist in precipitating clouds. Gaseous SO/sub 2/ and H/sub 2/O/submore » 2/ are also commonly simultaneously present in clear air; in the mixed layer either species maybe in excess, but H/sub 2/O/sub 2/ present with SO/sub 2/ in precipitating clouds is attributed to material dissolved in falling hydrometeors which has not had time to react with SO/sub 2/. This supported by model calculations evaluating the characteristic time and distance for reaction of aqueous H/sub 2/O/sub 2/ in droplets falling through an SO/sub 2/-containing layer. 29 refs., 6 figs.« less

Air quality impact of the coal-fired power plants in the northern passageway of the China West-East Power Transmission Project.

PubMed

Xue, Zhigang; Hao, Jiming; Chai, Fahe; Duan, Ning; Chen, Yizhen; Li, Jindan; Chen, Fu; Liu, Simei; Pu, Wenqing

2005-12-01

This paper analyzes the air quality impacts of coal-fired power plants in the northern passageway of the West-East Power Transmission Project in China. A three-layer Lagrangian model called ATMOS, was used to simulate the spatial distribution of incremental sulfur dioxide (SO2) and coarse particulate matter (PM10) concentrations under different emission control scenarios. In the year 2005, the emissions from planned power plants mainly affected the air quality of Shanxi, Shaanxi, the common boundary of Inner Mongolia and Shanxi, and the area around the boundary between Inner Mongolia and Ningxia. In these areas, the annually averaged incremental SO2 and PM10 concentrations exceed 2 and 2.5 microg/m3, respectively. The maximum increases of the annually averaged SO2 and PM10 concentrations are 8.3 and 7.2 microg/m3, respectively, which occur around Hancheng city, near the boundary of the Shaanxi and Shanxi provinces. After integrated control measures are considered, the maximum increases of annually averaged SO2 and PM10 concentrations fall to 4.9 and 4 microg/m3, respectively. In the year 2010, the areas affected by planned power plants are mainly North Shaanxi, North Ningxia, and Northwest Shanxi. The maximum increases of the annually averaged SO2 and PM10, concentrations are, respectively, 6.3 and 5.6 microg/m3, occurring in Northwest Shanxi, which decline to 4.4 and 4.1 microg/m3 after the control measures are implemented. The results showed that the proposed power plants mainly affect the air quality of the region where the power plants are built, with little impact on East China where the electricity will be used. The influences of planned power plants on air quality will be decreased greatly by implementing integrated control measures.

Endogenous Sulfur Dioxide: A New Member of Gasotransmitter Family in the Cardiovascular System

PubMed Central

Huang, Yaqian; Tang, Chaoshu; Du, Junbao; Jin, Hongfang

2016-01-01

Sulfur dioxide (SO2) was previously regarded as a toxic gas in atmospheric pollutants. But it has been found to be endogenously generated from metabolism of sulfur-containing amino acids in mammals through transamination by aspartate aminotransferase (AAT). SO2 could be produced in cardiovascular tissues catalyzed by its synthase AAT. In recent years, studies revealed that SO2 had physiological effects on the cardiovascular system, including vasorelaxation and cardiac function regulation. In addition, the pathophysiological effects of SO2 were also determined. For example, SO2 ameliorated systemic hypertension and pulmonary hypertension, prevented the development of atherosclerosis, and protected against myocardial ischemia-reperfusion (I/R) injury and isoproterenol-induced myocardial injury. These findings suggested that endogenous SO2 was a novel gasotransmitter in the cardiovascular system and provided a new therapy target for cardiovascular diseases. PMID:26839635

Endogenous Sulfur Dioxide: A New Member of Gasotransmitter Family in the Cardiovascular System.

PubMed

Huang, Yaqian; Tang, Chaoshu; Du, Junbao; Jin, Hongfang

2016-01-01

Sulfur dioxide (SO2) was previously regarded as a toxic gas in atmospheric pollutants. But it has been found to be endogenously generated from metabolism of sulfur-containing amino acids in mammals through transamination by aspartate aminotransferase (AAT). SO2 could be produced in cardiovascular tissues catalyzed by its synthase AAT. In recent years, studies revealed that SO2 had physiological effects on the cardiovascular system, including vasorelaxation and cardiac function regulation. In addition, the pathophysiological effects of SO2 were also determined. For example, SO2 ameliorated systemic hypertension and pulmonary hypertension, prevented the development of atherosclerosis, and protected against myocardial ischemia-reperfusion (I/R) injury and isoproterenol-induced myocardial injury. These findings suggested that endogenous SO2 was a novel gasotransmitter in the cardiovascular system and provided a new therapy target for cardiovascular diseases.

Chemically activated manganese dioxide for dry batteries

NASA Astrophysics Data System (ADS)

Askar, M.; Abbas, H.

1994-10-01

The present investigation has enabled us to convert inactive beta-manganese dioxide to high electrochemically active types by chemical processes. Natural and chemically prepared beta-manganese dioxides were roasted at 1050 C to form Mn3O4. This compound was subjected to activation treatment using hydrochloric and sulfuric acid under various reaction conditions. The manganese dioxide so obtained was examined by x-ray diffraction, thermogravimetric, differential thermal, and chemical analyses. The structure of the dioxide obtained was found to be greatly dependent on the origin of MnO2 and type of acid used. Treatment with hydrochloric acid yielded the so-called gamma-variety while sulfuric acid tended to produce gamma- or alpha-MnO2. In addition, waste manganese sulfate obtained as by-product from sulfuric acid digestion treatment was recycled and electrolytically oxidized to gamma-MnO2. The discharge performance of the above-mentioned MnO2 samples as battery cathodic active material was evaluated and compared with the ordinary battery grade.

Effect of Nanoparticles on the Survival and Development of Vitrified Porcine GV Oocytes.

PubMed

Li, W J; Zhou, X L; Liu, B L; Dai, J J; Song, P; Teng, Y

BACKGROUND: Some mammalian oocytes have been successfully cryopreserved by vitrification. However, the survival and developmental rate of vitrified oocytes is still low. The incorporation of nanoparticles into cryoprotectant (CPA) may improve the efficiency of vitrification by changing the properties of solutions. The toxicity of different concentrations of hydroxy apatite (HA), silica dioxide (SO 2 ), aluminum oxide (Al 2 O 3 ) and titanium dioxide (TiO 2 ) nanoparticles (20 nm in diameter) to oocytes was tested and the toxicity threshold value of each nanoparticle was determined. Porcine GV oocytes were vitrified in optimized nano-CPA, and effects of diameter and concentration of nanoparticles on the survival rate and developmental rate of porcine GV oocytes were compared. HA nanoparticles have demonstrated the least toxicity among four nanoparticles and the developmental rate of GV-stage porcine oocytes was 100% when its concentration was lower than 0.5%. By adding 0.1% HA into VS, the developmental rate of GV-stage porcine oocytes (22%) was significantly higher than other groups. The effect of vitrification in nano-CPA on oocytes was related to the concentration of HA nanoparticles rather than their size. By adding 0.05% HA nanoparticles (60nm in diameter), the developmental rate increased dramatically from 14.7% to 30.4%. Nano-cryopreservation offers a new way to improve the effect of survival and development of oocytes, but the limitation of this technology shall not be ignored.

Carbon Disulfide (CS2) Mechanisms in Formation of Atmospheric Carbon Dioxide (CO2) Formation from Unconventional Shale Gas Extraction and Processing Operations and Global Climate Change.

PubMed

Rich, Alisa L; Patel, Jay T

2015-01-01

Carbon disulfide (CS2) has been historically associated with the production of rayon, cellophane, and carbon tetrachloride. This study identifies multiple mechanisms by which CS2 contributes to the formation of CO2 in the atmosphere. CS2 and other associated sulfide compounds were found by this study to be present in emissions from unconventional shale gas extraction and processing (E&P) operations. The breakdown products of CS2; carbonyl sulfide (COS), carbon monoxide (CO), and sulfur dioxide (SO2) are indirect greenhouse gases (GHGs) that contribute to CO2 levels in the atmosphere. The heat-trapping nature of CO2 has been found to increase the surface temperature, resulting in regional and global climate change. The purpose of this study is to identify five mechanisms by which CS2 and the breakdown products of CS2 contribute to atmospheric concentrations of CO2. The five mechanisms of CO2 formation are as follows: Chemical Interaction of CS2 and hydrogen sulfide (H2S) present in natural gas at high temperatures, resulting in CO2 formation;Combustion of CS2 in the presence of oxygen producing SO2 and CO2;Photolysis of CS2 leading to the formation of COS, CO, and SO2, which are indirect contributors to CO2 formation;One-step hydrolysis of CS2, producing reactive intermediates and ultimately forming H2S and CO2;Two-step hydrolysis of CS2 forming the reactive COS intermediate that reacts with an additional water molecule, ultimately forming H2S and CO2. CS2 and COS additionally are implicated in the formation of SO2 in the stratosphere and/or troposphere. SO2 is an indirect contributor to CO2 formation and is implicated in global climate change.

Large-volume constant-concentration sampling technique coupling with surface-enhanced Raman spectroscopy for rapid on-site gas analysis

NASA Astrophysics Data System (ADS)

Zhang, Zhuomin; Zhan, Yisen; Huang, Yichun; Li, Gongke

2017-08-01

In this work, a portable large-volume constant-concentration (LVCC) sampling technique coupling with surface-enhanced Raman spectroscopy (SERS) was developed for the rapid on-site gas analysis based on suitable derivatization methods. LVCC sampling technique mainly consisted of a specially designed sampling cell including the rigid sample container and flexible sampling bag, and an absorption-derivatization module with a portable pump and a gas flowmeter. LVCC sampling technique allowed large, alterable and well-controlled sampling volume, which kept the concentration of gas target in headspace phase constant during the entire sampling process and made the sampling result more representative. Moreover, absorption and derivatization of gas target during LVCC sampling process were efficiently merged in one step using bromine-thiourea and OPA-NH4+ strategy for ethylene and SO2 respectively, which made LVCC sampling technique conveniently adapted to consequent SERS analysis. Finally, a new LVCC sampling-SERS method was developed and successfully applied for rapid analysis of trace ethylene and SO2 from fruits. It was satisfied that trace ethylene and SO2 from real fruit samples could be actually and accurately quantified by this method. The minor concentration fluctuations of ethylene and SO2 during the entire LVCC sampling process were proved to be < 4.3% and 2.1% respectively. Good recoveries for ethylene and sulfur dioxide from fruit samples were achieved in range of 95.0-101% and 97.0-104% respectively. It is expected that portable LVCC sampling technique would pave the way for rapid on-site analysis of accurate concentrations of trace gas targets from real samples by SERS.

Large-volume constant-concentration sampling technique coupling with surface-enhanced Raman spectroscopy for rapid on-site gas analysis.

PubMed

Zhang, Zhuomin; Zhan, Yisen; Huang, Yichun; Li, Gongke

2017-08-05

In this work, a portable large-volume constant-concentration (LVCC) sampling technique coupling with surface-enhanced Raman spectroscopy (SERS) was developed for the rapid on-site gas analysis based on suitable derivatization methods. LVCC sampling technique mainly consisted of a specially designed sampling cell including the rigid sample container and flexible sampling bag, and an absorption-derivatization module with a portable pump and a gas flowmeter. LVCC sampling technique allowed large, alterable and well-controlled sampling volume, which kept the concentration of gas target in headspace phase constant during the entire sampling process and made the sampling result more representative. Moreover, absorption and derivatization of gas target during LVCC sampling process were efficiently merged in one step using bromine-thiourea and OPA-NH 4 + strategy for ethylene and SO 2 respectively, which made LVCC sampling technique conveniently adapted to consequent SERS analysis. Finally, a new LVCC sampling-SERS method was developed and successfully applied for rapid analysis of trace ethylene and SO 2 from fruits. It was satisfied that trace ethylene and SO 2 from real fruit samples could be actually and accurately quantified by this method. The minor concentration fluctuations of ethylene and SO 2 during the entire LVCC sampling process were proved to be <4.3% and 2.1% respectively. Good recoveries for ethylene and sulfur dioxide from fruit samples were achieved in range of 95.0-101% and 97.0-104% respectively. It is expected that portable LVCC sampling technique would pave the way for rapid on-site analysis of accurate concentrations of trace gas targets from real samples by SERS. Copyright © 2017 Elsevier B.V. All rights reserved.

Interference of oxygen, carbon dioxide, and water vapor on the analysis for oxides of nitrogen by chemiluminescence

NASA Technical Reports Server (NTRS)

Maahs, H. G.

1975-01-01

The interference of small concentrations (less than 4 percent by volume) of oxygen, carbon dioxide, and water vapor on the analysis for oxides of nitrogen by chemiluminescence was measured. The sample gas consisted primarily of nitrogen, with less than 100 parts per million concentration of nitric oxide, and with small concentrations of oxygen, carbon dioxide, and water vapor added. Results obtained under these conditions indicate that although oxygen does not measurably affect the analysis for nitric oxide, the presence of carbon dioxide and water vapor causes the indicated nitric oxide concentration to be too low. An interference factor - defined as the percentage change in indicated nitric oxide concentration (relative to the true nitric oxide concentration) divided by the percent interfering gas present - was determined for carbon dioxide to be -0.60 + or - 0.04 and for water vapor to be -2.1 + or - 0.3.

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

PubMed

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.

Infrared Hollow Optical Fiber Probe for Localized Carbon Dioxide Measurement in Respiratory Tracts.

PubMed

Katagiri, Takashi; Shibayama, Kyosuke; Iida, Takeru; Matsuura, Yuji

2018-03-27

A real-time gas monitoring system based on optical absorption spectroscopy is proposed for localized carbon dioxide (CO₂) measurement in respiratory tracts. In this system, a small gas cell is attached to the end of a hollow optical fiber that delivers mid-infrared light with small transmission loss. The diameters of the fiber and the gas cell are smaller than 1.2 mm so that the probe can be inserted into a working channel of common bronchoscopes. The dimensions of the gas cell are designed based on absorption spectra of CO₂ standard gases in the 4.2 μm wavelength region, which are measured using a Fourier-transform infrared spectrometer. A miniature gas cell that is comprised of a stainless-steel tube with slots for gas inlet and a micro-mirror is fabricated. A compact probing system with a quantum cascade laser (QCL) light source is built using a gas cell with a hollow optical fiber for monitoring CO₂ concentration. Experimental results using human breaths show the feasibility of the system for in-situ measurement of localized CO₂ concentration in human airways.

Health and air quality benefits of policies to reduce coal-fired power plant emissions: a case study in North Carolina.

PubMed

Li, Ya-Ru; Gibson, Jacqueline MacDonald

2014-09-02

We analyzed sulfur dioxide (SO2) emissions and fine particulate sulfate (PM2.5 sulfate) concentrations in the southeastern United States during 2002-2012, in order to evaluate the health impacts in North Carolina (NC) of the NC Clean Smokestacks Act of 2002. This state law required progressive reductions (beyond those mandated by federal rules) in pollutant emissions from NC's coal-fired power plants. Although coal-fired power plants remain NC's leading SO2 source, a trend analysis shows significant declines in SO2 emissions (-20.3%/year) and PM2.5 sulfate concentrations (-8.7%/year) since passage of the act. Emissions reductions were significantly greater in NC than in neighboring states, and emissions and PM2.5 sulfate concentration reductions were highest in NC's piedmont region, where 9 of the state's 14 major coal-fired power plants are located. Our risk model estimates that these air quality improvements decreased the risk of premature death attributable to PM2.5 sulfate in NC by about 63%, resulting in an estimated 1700 (95% CI: 1500, 1800) deaths prevented in 2012. These findings lend support to recent studies predicting that implementing the proposed federal Cross-State Air Pollution Rule (recently upheld by the U.S. Supreme Court) could substantially decrease U.S. premature deaths attributable to coal-fired power plant emissions.

AERMOD performance evaluation for three coal-fired electrical generating units in Southwest Indiana.

PubMed

Frost, Kali D

2014-03-01

An evaluation of the steady-state dispersion model AERMOD was conducted to determine its accuracy at predicting hourly ground-level concentrations of sulfur dioxide (SO2) by comparing model-predicted concentrations to a full year of monitored SO2 data. The two study sites are comprised of three coal-fired electrical generating units (EGUs) located in southwest Indiana. The sites are characterized by tall, buoyant stacks,flat terrain, multiple SO2 monitors, and relatively isolated locations. AERMOD v12060 and AERMOD v12345 with BETA options were evaluated at each study site. For the six monitor-receptor pairs evaluated, AERMOD showed generally good agreement with monitor values for the hourly 99th percentile SO2 design value, with design value ratios that ranged from 0.92 to 1.99. AERMOD was within acceptable performance limits for the Robust Highest Concentration (RHC) statistic (RHC ratios ranged from 0.54 to 1.71) at all six monitors. Analysis of the top 5% of hourly concentrations at the six monitor-receptor sites, paired in time and space, indicated poor model performance in the upper concentration range. The amount of hourly model predicted data that was within a factor of 2 of observations at these higher concentrations ranged from 14 to 43% over the six sites. Analysis of subsets of data showed consistent overprediction during low wind speed and unstable meteorological conditions, and underprediction during stable, low wind conditions. Hourly paired comparisons represent a stringent measure of model performance; however given the potential for application of hourly model predictions to the SO2 NAAQS design value, this may be appropriate. At these two sites, AERMOD v12345 BETA options do not improve model performance. A regulatory evaluation of AERMOD utilizing quantile-quantile (Q-Q) plots, the RHC statistic, and 99th percentile design value concentrations indicates that model performance is acceptable according to widely accepted regulatory performance limits. However, a scientific evaluation examining hourly paired monitor and model values at concentrations of interest indicates overprediction and underprediction bias that is outside of acceptable model performance measures. Overprediction of 1-hr SO2 concentrations by AERMOD presents major ramifications for state and local permitting authorities when establishing emission limits.

Procedures for Processing Requests to Redesignate Areas to Attainment

EPA Pesticide Factsheets

Guidance for processing requests for redesignation of nonattainment areas to attainment for ozone (O3), carbon monoxide (CO), particulate matter (PM-10), sulfur dioxide (SO2), nitrogen dioxide (NO2), and lead (Pb).

42 CFR 84.207 - Bench tests; gas and vapor tests; minimum requirements; general.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 64 3 50 50 Ammonia Equilibrated NH3 1000 32 4 50 50 Chlorine As received Cl2 500 64 3 5 35 Chlorine... 4 5 50 Sulfur dioxide As received SO2 500 64 3 5 30 Sulfur dioxide Equilibrated SO2 500 32 4 5 30 1... respiratory protection against more than one type of gas or vapor, as for use in ammonia and in chlorine, the...

42 CFR 84.207 - Bench tests; gas and vapor tests; minimum requirements; general.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 64 3 50 50 Ammonia Equilibrated NH3 1000 32 4 50 50 Chlorine As received Cl2 500 64 3 5 35 Chlorine... 4 5 50 Sulfur dioxide As received SO2 500 64 3 5 30 Sulfur dioxide Equilibrated SO2 500 32 4 5 30 1... respiratory protection against more than one type of gas or vapor, as for use in ammonia and in chlorine, the...

Short term effects of air pollution on mortality in the city of Lyon, France, 1985-90.

PubMed Central

Zmirou, D; Barumandzadeh, T; Balducci, F; Ritter, P; Laham, G; Ghilardi, J P

1996-01-01

OBJECTIVE: The short term association between daily mortality and ambient air pollution in the city of Lyon, France (population, 410,000) between 1985 and 1990 was assessed using time series analysis. DESIGN: This study followed the standardised design and statistical analysis (Poisson regression) that characterise the APHEA project. METHODS: Four categories of cause of death were studied: total (minus external causes), respiratory, cardiovascular, and digestive causes (as a control condition). RESULTS: No association was found with any cause of death for nitrogen dioxide (NO2) and ozone (O3), nor, for any pollutant, for digestive conditions. Sulphur dioxide (SO2) and, to a much lesser degree, suspended particles (PM13), were significantly related to mortality from respiratory and cardiovascular conditions. The relative risk (RR) of respiratory deaths associated with a 50 micrograms/m3 increment of mean daily SO2 over the whole period was 1.22 (95% CI 1.05, 1.40); the RR for cardiovascular deaths was 1.54 (1.22, 1.96). The corresponding RRs for PM13 were 1.04 (1.00, 1.09) for respiratory mortality and 1.04 (0.99, 1.10) for cardiovascular deaths. CONCLUSIONS: The effects of particulates were slightly increased during the cold season. When particulates concentrations were greater than 60 micrograms/m3, the joint SO2 effect was increased, suggesting some interaction between the two pollution indicators. These results agree with other studies showing an association between particulate pollution and daily mortality; however, they also suggest the noxious effect of SO2. PMID:8758221

Method and system for capturing carbon dioxide and/or sulfur dioxide from gas stream

DOEpatents

Chang, Shih-Ger; Li, Yang; Zhao, Xinglei

2014-07-08

The present invention provides a system for capturing CO.sub.2 and/or SO.sub.2, comprising: (a) a CO.sub.2 and/or SO.sub.2 absorber comprising an amine and/or amino acid salt capable of absorbing the CO.sub.2 and/or SO.sub.2 to produce a CO.sub.2- and/or SO.sub.2-containing solution; (b) an amine regenerator to regenerate the amine and/or amino acid salt; and, when the system captures CO.sub.2, (c) an alkali metal carbonate regenerator comprising an ammonium catalyst capable catalyzing the aqueous alkali metal bicarbonate into the alkali metal carbonate and CO.sub.2 gas. The present invention also provides for a system for capturing SO.sub.2, comprising: (a) a SO.sub.2 absorber comprising aqueous alkali metal carbonate, wherein the alkali metal carbonate is capable of absorbing the SO.sub.2 to produce an alkali metal sulfite/sulfate precipitate and CO.sub.2.

A Review of Major Non-Power-Related Carbon Dioxide Stream Compositions

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

Last, George V.; Schmick, Mary T.

A critical component in the assessment of long-term risk from geologic sequestration of carbon dioxide (CO2) is the ability to predict mineralogical and geochemical changes within storage reservoirs as a result of rock-brine-CO2 reactions. Impurities and/or other constituents in CO2 source streams selected for sequestration can affect both the chemical and physical (e.g., density, viscosity, interfacial tension) properties of CO2 in the deep subsurface. The nature and concentrations of these impurities are a function of both the industrial source(s) of CO2, as well as the carbon capture technology used to extract the CO2 and produce a concentrated stream for subsurfacemore » injection and geologic sequestration. This article reviews the relative concentrations of CO2 and other constituents in exhaust gases from major non-energy-related industrial sources of CO2. Assuming that carbon capture technology would remove most of the incondensable gases N2, O2, and Ar, leaving SO2 and NOx as the main impurities, the authors then summarize the relative proportions of the remaining impurities assumed to be present in CO2 source streams that could be targeted for geologic sequestration. The summary is presented relative to five potential sources of CO2: 1) Flue Gas with Flue Gas Desulfurization, 2) Combustion Stack from Coke Production, 3) Portland Cement Kilns, 4) Natural Gas Combustion, and 5) Lime Production.« less

Sagebrush and grasshopper responses to atmospheric carbon dioxide concentration.

PubMed

Johnson, R H; Lincoln, D E

1990-08-01

Seed- and clonally-propagated plants of Big Sagebrush (Artemisia tridentata var.tridentata) were grown under atmospheric carbon dioxide regimes of 270, 350 and 650 μl l -1 and fed toMelanoplus differentialis andM. sanguinipes grasshoppers. Total shrub biomass significantly increased as carbon dioxide levels increased, as did the weight and area of individual leaves. Plants grown from seed collected in a single population exhibited a 3-5 fold variation in the concentration of leaf volatile mono- and sesquiterpenes, guaianolide sesquiterpene lactones, coumarins and flavones within each CO 2 treatment. The concentration of leaf allelochemicals did not differ significantly among CO 2 treatments for these seed-propagated plants. Further, when genotypic variation was controlled by vegetative propagation, allelochemical concentrations also did not differ among carbon dioxide treatments. On the other hand, overall leaf nitrogen concentration declined significantly with elevated CO 2 . Carbon accumulation was seen to dilute leaf nitrogen as the balance of leaf carbon versus nitrogen progressively increased as CO 2 growth concentration increased. Grasshopper feeding was highest on sagebrush leaves grown under 270 and 650 μl l -1 CO 2 , but varied widely within treatments. Leaf nitrogen concentration was an important positive factor in grasshopper relative growth but had no overall effect on consumption. Potential compensatory consumption by these generalist grasshoppers was apparently limited by the sagebrush allelochemicals. Insects with a greater ability to feed on chemically defended host plants under carbon dioxide enrichment may ultimately consume leaves with a lower nitrogen concentration but the same concentration of allelochemicals. Compensatory feeding may potentially increase the amount of dietary allelochemicals ingested for each unit of nitrogen consumed.

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

PubMed

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 (P<0.01). Compared with EG, the body weight growth rate of SEG significantly decreased (P<0.01) and cardiac index and left ventricular index decreased but without a significant difference. Compared with EG, myocardial Hyp and collagen concentration, myocardial collagen volume fraction (CVF), perivascular collagen area (PVCA), and the expression of AT1R and CTGF in myocardium of SEG increased significantly (P<0.01). CONCLUSIONS SO2 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.

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

Voynikova, D. S., E-mail: desi-sl2000@yahoo.com; Gocheva-Ilieva, S. G., E-mail: snegocheva@yahoo.com; Ivanov, A. V., E-mail: aivanov-99@yahoo.com

Numerous time series methods are used in environmental sciences allowing the detailed investigation of air pollution processes. The goal of this study is to present the empirical analysis of various aspects of stochastic modeling and in particular the ARIMA/SARIMA methods. The subject of investigation is air pollution in the town of Kardzhali, Bulgaria with 2 problematic pollutants – sulfur dioxide (SO2) and particulate matter (PM10). Various SARIMA Transfer Function models are built taking into account meteorological factors, data transformations and the use of different horizons selected to predict future levels of concentrations of the pollutants.

Changes in the chemistry of precipitation in the United States, 1981-1998

USGS Publications Warehouse

Nilles, M.A.; Conley, B.E.

2001-01-01

Regulatory measures in the United States, such as Title IV of the Clean Air Act Amendments of 1990, have primarily restricted sulfur dioxide emissions as a way to control acidic deposition. These restrictions, coupled with increasing concentrations of NH4+ in wet deposition in some regions of the U.S. and continued high emissions of nitrogen oxides have generated a significant shift in the chemistry of precipitation as measured at National Atmospheric Deposition Program/National Trends Network sites. Trends in precipitation chemistry at NADP/NTN sites were evaluated for statistical significance for the period 1981-1998 using a Seasonal Mann-Kendall Test, a robust non-parametric test for detection of monotonic trends. SO42- declines were detected at 100 of the 147 sites examined while no sites exhibited increasing SO42- trends. On average, SO42- declined 35% over the period 1981-1998 with downward SO42- trends being most pronounced in the northeastern United States. In contrast, no consistent trends in NO3- concentrations were observed in precipitation in any major region of the United States. Although the majority of sites did not exhibit significant trends in NH4+ concentration, 30 sites exhibited upward trends. For Ca2+ concentration in precipitation, 64 sites exhibited a significant decreasing trend and no sites exhibited an upward trend.

The Role of Sulfur Dioxide in Stratospheric Aerosol Formation Evaluated Using In Situ Measurements in the Tropical Lower Stratosphere

NASA Technical Reports Server (NTRS)

Rollins, A. W.; Thornberry, T. D.; Watts, L. A.; Yu, P.; Rosenlof, K. H.; Mills, M.; Baumann, E.; Girogetta, F. R.; Bui, T. V.; Hopfner, M.;

The Role of Sulfur Dioxide in Stratospheric Aerosol Formation Evaluated Using In-Situ Measurements in the Tropical Lower Stratosphere.

PubMed

Rollins, A W; Thornberry, T D; Watts, L A; Yu, P; Rosenlof, K H; Mills, M; Baumann, E; Giorgetta, F R; Bui, T V; Höpfner, M; Walker, K A; Boone, C; Bernath, P F; Colarco, P R; Newman, P A; Fahey, D W; Gao, R S

2017-05-16

Stratospheric aerosols (SAs) are a variable component of the Earth's albedo that may be intentionally enhanced in the future to offset greenhouse gases (geoengineering). The role of tropospheric-sourced sulfur dioxide (SO 2 ) in maintaining background SAs has been debated for decades without in-situ measurements of SO 2 at the tropical tropopause to inform this issue. Here we clarify the role of SO 2 in maintaining SAs by using new in-situ SO 2 measurements to evaluate climate models and satellite retrievals. We then use the observed tropical tropopause SO 2 mixing ratios to estimate the global flux of SO 2 across the tropical tropopause. These analyses show that the tropopause background SO 2 is about 5 times smaller than reported by the average satellite observations that have been used recently to test atmospheric models. This shifts the view of SO 2 as a dominant source of SAs to a near-negligible one, possibly revealing a significant gap in the SA budget.

Houston’s rapid ozone increases: preconditions and geographic origins

PubMed Central

Couzo, Evan; Jeffries, Harvey E.; Vizuete, William

2013-01-01

Many of Houston’s highest 8-h ozone (O3) peaks are characterised by increases in concentrations of at least 40 ppb in 1 h, or 60 ppb in 2 h. These rapid increases are called non-typical O3 changes (NTOCs). In 2004, the Texas Commission on Environmental Quality (TCEQ) developed a novel emissions control strategy aimed at eliminating NTOCs. The strategy limited routine and short-term emissions of ethene, propene, 1,3-butadiene and butene isomers, collectively called highly reactive volatile organic compounds (HRVOCs), which are released from petrochemical facilities. HRVOCs have been associated with NTOCs through field campaigns and modelling studies. This study analysed wind measurements and O3, formaldehyde (HCHO) and sulfur dioxide (SO2) concentrations from 2000 to 2011 at 25 ground monitors in Houston. NTOCs almost always occurred when monitors were downwind of petrochemical facilities. Rapid O3 increases were associated with low wind speeds; 75 % of NTOCs occurred when the 3-h average wind speed preceding the event was less than 6.5 km h−1. Statistically significant differences in HCHO concentrations were seen between days with and without NTOCs. Early afternoon HCHO concentrations were greater on NTOC days. In the morning before an observed NTOC event, however, there were no significant differences in HCHO concentrations between days with and without NTOCs. Hourly SO2 concentrations also increased rapidly, exhibiting behaviour similar to NTOCs. Oftentimes, the SO2 increases preceded a NTOC. These findings show that, despite the apparent success of targeted HRVOC emission controls, further restrictions may be needed to eliminate the remaining O3 events. PMID:24014080

Effects of acetic acid, ethanol, and SO(2) on the removal of volatile acidity from acidic wines by two Saccharomyces cerevisiae commercial strains.

PubMed

Vilela-Moura, Alice; Schuller, Dorit; Mendes-Faia, Arlete; Côrte-Real, Manuela

2010-07-01

Herein, we report the influence of different combinations of initial concentration of acetic acid and ethanol on the removal of acetic acid from acidic wines by two commercial Saccharomyces cerevisiae strains S26 and S29. Both strains reduced the volatile acidity of an acidic wine (1.0 gl(-1) acetic acid and 11% (v/v) ethanol) by 78% and 48%, respectively. Acetic acid removal by strains S26 and S29 was associated with a decrease in ethanol concentration of 0.7 and 1.2% (v/v), respectively. Strain S26 revealed better removal efficiency due to its higher tolerance to stress factors imposed by acidic wines. Sulfur dioxide (SO(2)) in the concentration range 95-170 mg l(-1)inhibits the ability of both strains to reduce the volatile acidity of the acidic wine used under our experimental conditions. Therefore, deacidification should be carried out either in wines stabilized by filtration or in wines with SO(2)concentrations up to 70 mg l(-1). Deacidification of wines with the better performing strain S26 was associated with changes in the concentration of volatile compounds. The most pronounced increase was observed for isoamyl acetate (banana) and ethyl hexanoate (apple, pineapple), with an 18- and 25-fold increment, respectively, to values above the detection threshold. The acetaldehyde concentration of the deacidified wine was 2.3 times higher, and may have a detrimental effect on the wine aroma. Moreover, deacidification led to increased fatty acids concentration, but still within the range of values described for spontaneous fermentations, and with apparently no negative impact on the organoleptical properties.

The airborne lava-seawater interaction plume at Kilauea Volcano, Hawai'i

USGS Publications Warehouse

Edmonds, M.; Gerlach, T.M.

2006-01-01

Lava flows into the sea at Kīlauea Volcano, Hawaiʻi, and generates an airborne gas and aerosol plume. Water (H2O), hydrogen chloride (HCl), carbon dioxide (CO2), nitrogen dioxide (NO2) and sulphur dioxide (SO2) gases were quantified in the plume in 2004–2005, using Open Path Fourier Transform infra-red Spectroscopy. The molar abundances of these species and thermodynamic modelling are used to discuss their generation. The range in molar HCl / H2O confirms that HCl is generated when seawater is boiled dry and magnesium salts are hydrolysed (as proposed by [T.M. Gerlach, J.L. Krumhansl, R.O. Fournier, J. Kjargaard, Acid rain from the heating and evaporation of seawater by molten lava: a new volcanic hazard, EOS (Trans. Am. Geophys. Un.) 70 (1989) 1421–1422]), in contrast to models of Na-metasomatism. Airborne droplets of boiled seawater brine form nucleii for subsequent H2O and HCl condensation, which acidifies the droplets and liberates CO2 gas from bicarbonate and carbonate. NO2 is derived from the thermal decomposition of nitrates in coastal seawater, which takes place as the lava heats droplets of boiled seawater brine to 350–400 °C. SO2 is derived from the degassing of subaerial lava flows on the coastal plain. The calculated mass flux of HCl from a moderate-sized ocean entry significantly increases the total HCl emission at Kīlauea (including magmatic sources) and is comparable to industrial HCl emitters in the United States. For larger lava ocean entries, the flux of HCl will cause intense local environmental hazards, such as high localised HCl concentrations and acid rain.

Simultaneous gas chromatographic determination of four toxic gases generally present in combustion atmospheres.

PubMed

Endecott, B R; Sanders, D C; Chaturvedi, A K

1996-01-01

The measurement of combustion gases produced by burning aircraft cabin materials poses a continuing limitation for smoke toxicity research. Because toxic effects of gases depend on both their concentrations and the duration of exposure, frequent atmosphere sampling is necessary to define the gas concentration-exposure time curve. A gas chromatographic (GC) method was developed for the simultaneous analyses of carbon monoxide (CO), hydrogen sulfide (H2S), sulfur dioxide (SO2), and hydrogen cyanide (HCN). The method used an MTI M200 dual-column gas chromatograph equipped with 4-m molecular sieve-5A and 8-m PoraPlot-U wall-coated capillary columns and two low-volume, high-sensitivity thermal conductivity detectors. Detectability (in parts per million [ppm]) and retention times (in seconds) for the gases were as follows: CO, 100 ppm, 28 s; H2S, 50 ppm, 26 s; SO2, 125 ppm, 76 s; and HCN, 60 ppm, 108 s. The method was effective for determining these gases in mixtures and in the combustion atmospheres generated by burning wool (CO, HCN, and H2S) and modacrylic fabrics (CO and HCN). Common atmospheric gaseous or combustion products (oxygen, carbon dioxide, nitrogen, water vapor, and other volatiles) did not interfere with the analyses. However, filtration of the combustion atmospheres was necessary to prevent restriction of the GC sampling inlet by smoke particulates. The speed, sensitivity, and selectivity of this method make it suitable for smoke toxicity research and for evaluating performance of passenger protective breathing equipment. Also, this method can potentially be modified to analyze these gases when they are liberated from biosamples.

40 CFR 97.203 - Measurements, abbreviations, and acronyms.

Code of Federal Regulations, 2010 CFR

2010-07-01

... PROGRAMS (CONTINUED) FEDERAL NOX BUDGET TRADING PROGRAM AND CAIR NOX AND SO2 TRADING PROGRAMS CAIR SO2.... O2—oxygen. ppm—parts per million. scfh—standard cubic feet per hour. SO2—sulfur dioxide. yr—year. ...

Higher plants as bioindicators of sulphur dioxide emissions in urban environments.

PubMed

Hijano, Concepción Fidalgo; Domínguez, Maria Dolores Petit; Gimínez, Rosario García; Sínchez, Pilar Hungría; García, Inís Sancho

2005-12-01

The evaluation of certain vascular plants that grow in the city of Madrid as biomonitors of SO(2) air pollution in urban environments has been carried out. Total concentration of sulphur in leaves of the chosen higher plants as well as other parameters in close relation to this contaminant (visible injury symptoms, chlorophyll a- and b-content and peroxidase activity) have been determined in order to study the spatial distribution and temporal changes in SO(2) deposition. Results obtained show that coniferous species such as Pinus pinea, were more sensitive to SO(2) atmospheric concentration than leafy species as Quercux ilex subspecies ballota and, in the same way, bush species, such as Pyracantha coccinea and Nerium oleander, were more sensitive than wooded species, such as Cedrus deodara and Pinus pinea, respectively. There is a higher accumulation of sulphur in vegetable species located near highways and dense traffic incidence roads and near areas with high density of population. The minimum values for accumulation of SO(2) were registered in winter and spring seasons (from January to April) due to the vegetative stop; while maximum values are obtained during the summer season (from June to September), due to the stoma opening. The highest increments in sulphur concentration, calculated as the difference between two consecutive months, are obtained in May and June for all considered species except for Cedrus deodara and Pyracantha coccinea, both species have few seasonal changes during the whole year. Some species are more sensitive to natural washing than others, showing a decrease in sulphur concentration after rainfall periods.

A simplified approach to analyze the effectiveness of NO2 and SO2 emission reduction of coal-fired power plant from OMI retrievals

NASA Astrophysics Data System (ADS)

Bai, Yang; Wu, Lixin; Zhou, Yuan; Li, Ding

2017-04-01

Nitrogen oxides (NOX) and sulfur dioxide (SO2) emissions from coal combustion, which is oxidized quickly in the atmosphere resulting in secondary aerosol formation and acid deposition, are the main resource causing China's regional fog-haze pollution. Extensive literature has estimated quantitatively the lifetimes and emissions of NO2 and SO2 for large point sources such as coal-fired power plants and cities using satellite measurements. However, rare of these methods is suitable for sources located in a heterogeneously polluted background. In this work, we present a simplified emission effective radius extraction model for point source to study the NO2 and SO2 reduction trend in China with complex polluted sources. First, to find out the time range during which actual emissions could be derived from satellite observations, the spatial distribution characteristics of mean daily, monthly, seasonal and annual concentration of OMI NO2 and SO2 around a single power plant were analyzed and compared. Then, a 100 km × 100 km geographical grid with a 1 km step was established around the source and the mean concentration of all satellite pixels covered in each grid point is calculated by the area weight pixel-averaging approach. The emission effective radius is defined by the concentration gradient values near the power plant. Finally, the developed model is employed to investigate the characteristic and evolution of NO2 and SO2 emissions and verify the effectiveness of flue gas desulfurization (FGD) and selective catalytic reduction (SCR) devices applied in coal-fired power plants during the period of 10 years from 2006 to 2015. It can be observed that the the spatial distribution pattern of NO2 and SO2 concentration in the vicinity of large coal-burning source was not only affected by the emission of coal-burning itself, but also closely related to the process of pollutant transmission and diffusion caused by meteorological factors in different seasons. Our proposed model can be used to identify the effective operation time of FGD and SCR equipped in coal-fired power plant.

Detection and Tracking of Volcanic Ash and SO2 and its Impact to Aviation

NASA Astrophysics Data System (ADS)

Osiensky, J.; Hall, T.

2008-12-01

The eruptions of Okmok and Kasatochi Volcanoes in August 2008 produced a combination of volcanic ash and SO2 (sulfur dioxide) that impacted aviation across Alaska and the North Pacific Region. The Anchorage Volcanic Ash Advisory Center (A-VAAC) worked closely with the Alaska Volcano Observatory (AVO) and Federal Aviation Administration (FAA) Air Route Traffic Control Center (ARTCC) to ensure that accurate and timely detection and forecast of the ash plume occurred. Volcanic ash poses a hazard to all forms of transportation, but has been shown to be especially dangerous to aviation. Even a small eruption with limited vertical extent to the ash cloud impacts aviation traffic. A significant eruption where the ash cloud penetrates the jet airways (greater than 20,000 feet) requires major re-routing of air traffic, or even the cancellation of flights to ensure the safety of the airways. The AAWU and the AVO have demonstrated substantial experience successfully tracking volcanic ash clouds during the past 15 years. The AAWU issues special aviation warnings for volcanic ash (Volcanic Ash SIGMETs (Significant Meteorological Information)) to warn aircraft of impending ash hazards. However, an additional potential hazard to aviation associated with volcanic eruptions is being examined. A Sulfur Dioxide (SO2) cloud was identified and tracked across the Aleutians, Gulf of Alaska, and eventually into the Lower 48 states. The size and coverage of the SO2 clouds from the Okmok and Kasatochi eruptions may be unprecedented. There are currently no requirements to advise, or warn for SO2 as a hazard to aviation. However, SO2 has been demonstrated as a marker for potential areas of lower concentration volcanic ash. Dispersion models, such as NOAAs HYSPLIT, that are used to track volcanic ash are currently not tuned to track gases such as SO2. SO2 may not be a direct hazard to aviation per se; However, SO2 mixed with water produces H2SO4 (sulfuric acid), and long term exposure to even low concentrations of sulfuric acid may lead to deterioration of airframe paint and acrylic aircraft windows as well as sulfate deposits in the engines. Airlines typically avoid SO2 clouds because these clouds often contain small amounts of ash as well. Relatively new OMI (Ozone Monitoring Instrument) data from the EOS-Aura satellite provides a much higher resolution depiction of the SO2 cloud; However, a major drawback to this capability is that the OMI sensor is located on a Polar Orbiter satellite (where the frequency of this data is sparse). Forecasters in Alaska typically receive only one pass per day from the OMI due to its orbital path. Additional research is needed to better define thresholds and impacts of volcanic ash and SO2 as it relates to aviation. More importantly this research must be transferred rapidly from the research community into forecast operations.

Effect of SO2 on the transport properties of an imidazolium ionic liquid and its lithium solution.

PubMed

Monteiro, Marcelo J; Ando, Rômulo A; Siqueira, Leonardo J A; Camilo, Fernanda F; Santos, Paulo S; Ribeiro, Mauro C C; Torresi, Roberto M

2011-08-11

Transport coefficients have been measured as a function of the concentration of sulfur dioxide, SO(2), dissolved in 1-butyl-2,3-dimethylimidazolium bis(trifluoromethylsulfonyl)imide, [BMMI][Tf(2)N], as well as in its lithium salt solution, Li[Tf(2)N]. The SO(2) reduces viscosity and density and increases conductivity and diffusion coefficients in both the neat [BMMI][Tf(2)N] and the [BMMI][Tf(2)N]-Li[Tf(2)N] solution. The conductivity enhancement is not assigned to a simple viscosity effect; the weakening of ionic interactions upon SO(2) addition also plays a role. Microscopic details of the SO(2) effect were unraveled using Raman spectroscopy and molecular dynamics (MD) simulations. The Raman spectra suggest that the Li(+)-[Tf(2)N] interaction is barely affected by SO(2), and the SO(2)-[Tf(2)N] interaction is weaker than previously observed in an investigation of an ionic liquid containing the bromide anion. Transport coefficients calculated by MD simulations show the same trend as the experimental data with respect to SO(2) content. The MD simulations provide structural information on SO(2) molecules around [Tf(2)N], in particular the interaction of the sulfur atom of SO(2) with oxygen and fluorine atoms of the anion. The SO(2)-[BMMI] interaction is also important because the [BMMI] cations with above-average mobility have a larger number of nearest-neighbor SO(2) molecules. © 2011 American Chemical Society

Associations of gestational and early life exposures to ambient air pollution with childhood respiratory diseases in Shanghai, China: A retrospective cohort study.

PubMed

Liu, Wei; Huang, Chen; Hu, Yu; Fu, Qingyan; Zou, Zhijun; Sun, Chanjuan; Shen, Li; Wang, Xueying; Cai, Jiao; Pan, Jun; Huang, Yanmin; Chang, Jing; Sun, Yuexia; Sundell, Jan

2016-01-01

Associations of ambient air pollutants with respiratory health are inconsistent. We analyzed the associations of gestational and early life exposures to air pollutants with doctor-diagnosed asthma, allergic rhinitis, and pneumonia in children. We selected 3358 preschool children who did not alter residences after birth from a cross-sectional study in 2011-2012 in Shanghai, China. Parents reported children's respiratory health history, home environment, and family lifestyle behaviors. We collected daily concentrations of sulphur dioxide (SO2), nitrogen dioxide (NO2), and particulate matter with an aerodynamic diameter ≤10μm (PM10) during the child's total lifetime (2006-2012) for each district where the children lived. We analyzed the associations using logistic regression models. After adjusting for covariates and the other studied pollutants, we found that exposure to NO2 (increment of 20μg/m(3)) during the first year of life was significantly associated with asthma [odds ratio (OR)=1.77; 95% confidence interval (CI): 1.29-2.43] and allergic rhinitis (OR=1.67; 95% CI: 1.07-2.61). Exposure to NO2 during gestation, the first two and three years, and over total lifetimewas all consistently associated with increased odds of allergic rhinitis. Quartiles of NO2 concentration during different exposure periods showed a slight dose-response relationship with the studied diseases. These diseases had significant associations with pollutant mixtures that included NO2, but had no significant association with exposures to SO2 and PM10 individually or in mixtures. Gestational and early life exposures to ambient NO2 are risk factors for childhood respiratory diseases. Copyright © 2016 Elsevier Ltd. All rights reserved.

Trans-boundary air pollution in a city under various atmospheric conditions.

PubMed

Luo, Ming; Hou, Xiangting; Gu, Yefu; Lau, Ngar-Cheung; Yim, Steve Hung-Lam

2018-03-15

Trans-boundary air pollution (TAP) is a crucial factor affecting air quality, and its contribution may vary over time and differ under various atmospheric conditions. This study firstly applies an integrated statistical scheme to estimate the contributions of TAP and local sources to air pollutants in a city, and then investigate the influences of tropical cyclones (TC) on TAP. Hong Kong is chosen as an example because of its significant and special TAP characteristics. This study focuses on four major air pollutants, namely, respirable and fine suspended particulates (RSP/PM 10 and FSP/PM 2.5 ), sulfur dioxide (SO 2 ), and nitrogen dioxide (NO 2 ), from 2002 to 2013. Our results show that, on average, TAP is the major contributor of the annual RSP, FSP, SO 2 , and NO 2 in Hong Kong. We estimate that when a TC is approaching, the increase in pollutant concentration in Hong Kong is mainly due to the increase in TAP contribution by the strengthened northerly wind at higher level of atmosphere (≥900hPa). These changes are accompanied by decreases in precipitation and increases in northerly/north-easterly wind, which may prolong the lifetime of pollutants, enhancing pollutant transport from mainland China to Hong Kong. Copyright © 2017 Elsevier B.V. All rights reserved.

Insights into the Electronic Structure of Ozone and Sulfur Dioxide from Generalized Valence Bond Theory: Addition of Hydrogen Atoms.

PubMed

Lindquist, Beth A; Takeshita, Tyler Y; Dunning, Thom H

2016-05-05

Ozone (O3) and sulfur dioxide (SO2) are valence isoelectronic species, yet their properties and reactivities differ dramatically. In particular, O3 is highly reactive, whereas SO2 is chemically relatively stable. In this paper, we investigate serial addition of hydrogen atoms to both the terminal atoms of O3 and SO2 and to the central atom of these species. It is well-known that the terminal atoms of O3 are much more amenable to bond formation than those of SO2. We show that the differences in the electronic structure of the π systems in the parent triatomic species account for the differences in the addition of hydrogen atoms to the terminal atoms of O3 and SO2. Further, we find that the π system in SO2, which is a recoupled pair bond dyad, facilitates the addition of hydrogen atoms to the sulfur atom, resulting in stable HSO2 and H2SO2 species.

Simultaneous removal of SO2 and trace SeO2 from flue gas: effect of SO2 on selenium capture and kinetics study.

PubMed

Li, Yuzhong; Tong, Huiling; Zhuo, Yuqun; Wang, Shujuan; Xu, Xuchang

2006-12-15

Sulfur dioxide (SO2) and trace elements are all pollutants derived from coal combustion. This study relates to the simultaneous removal of SO2 and trace selenium dioxide (SeO2) from flue gas by calcium oxide (CaO) adsorption in the moderate temperature range, especially the effect of SO2 presence on selenium capture. Experiments performed on a thermogravimetric analyzer (TGA) can reach the following conclusions. When the CaO conversion is relatively low and the reaction rate is controlled by chemical kinetics, the SO2 presence does not affect the selenium capture. When the CaO conversion is very high and the reaction rate is controlled by product layer diffusion, the SO2 presence and the product layer diffusion resistance jointly reduce the selenium capture. On the basis of the kinetics study, a method to estimate the trace selenium removal efficiency using kinetic parameters and the sulfur removal efficiency is developed.

A study of the total atmospheric sulfur dioxide load using ground-based measurements and the satellite derived Sulfur Dioxide Index

NASA Astrophysics Data System (ADS)

Georgoulias, A. K.; Balis, D.; Koukouli, M. E.; Meleti, C.; Bais, A.; Zerefos, C.

We present characteristics of the sulfur dioxide (SO 2) loading over Thessaloniki, Greece, and seven other selected sites around the world using SO 2 total column measurements from Brewer spectrophotometers together with satellite estimates of the Version 8 TOMS Sulfur Dioxide Index (SOI) over the same locations, retrieved from Nimbus 7 TOMS (1979-1993), Earth Probe TOMS (1996-2003) and OMI/Aura (2004-2006). Traditionally, the SOI has been used to quantify the SO 2 quantities emitted during great volcanic eruptions. Here, we investigate whether the SOI can give an indication of the total SO 2 load for areas and periods away from eruptive volcanic activity by studying its relative changes as a correlative measure to the SO 2 total column. We examined time series from Thessaloniki and another seven urban and non-urban stations, five in the European Union (Arosa, De Bilt, Hohenpeissenberg, Madrid, Rome) and two in India (Kodaikanal, New Delhi). Based on the Brewer data, Thessaloniki shows high SO 2 total columns for a European Union city but values are still low if compared to highly affected regions like those in India. For the time period 1983-2006 the SO 2 levels above Thessaloniki have generally decreased with a rate of 0.028 Dobson Units (DU) per annum, presumably due to the European Union's strict sulfur control policies. The seasonal variability of the SO 2 total column exhibits a double peak structure with two maxima, one during winter and the second during summer. The winter peak can be attributed to central heating while the summer peak is due to synoptic transport from sources west of the city and sources in the north of Greece. A moderate correlation was found between the seasonal levels of Brewer total SO 2 and SOI for Thessaloniki, Greece ( R = 0.710-0.763) and Madrid, Spain ( R = 0.691) which shows that under specific conditions the SOI might act as an indicator of the SO 2 total load.

Optimal control of algae growth by controlling CO 2 and nutrition flow using Pontryagin Maximum Principle

NASA Astrophysics Data System (ADS)

Mardlijah; Jamil, Ahmad; Hanafi, Lukman; Sanjaya, Suharmadi

2017-09-01

There are so many benefit of algae. One of them is using for renewable energy and sustainable in the future. The greater growth of algae will increasing biodiesel production and the increase of algae growth is influenced by glucose, nutrients and photosynthesis process. In this paper, the optimal control problem of the growth of algae is discussed. The objective function is to maximize the concentration of dry algae while the control is the flow of carbon dioxide and the nutrition. The solution is obtained by applying the Pontryagin Maximum Principle. and the result show that the concentration of algae increased more than 15 %.

A new process for converting SO2 to sulfur without generating secondary pollutants through reactions involving CaS and CaSO4.

PubMed

Sohn, H Y; Kim, Byung-Su

2002-07-01

Nonferrous smelters and coal gasification processes generate environmentally harmful sulfur dioxide streams, most of which are treated to produce sulfuric acid with the accompanying problems of market shortage and transportation difficulties. Some sulfur dioxide streams are scrubbed with an alkali solution or a solid substance such as limestone or dolomite, which in turn generates wastes that pose other pollution problems. While the conversion of sulfur dioxide to elemental sulfur has many environmental advantages, no processes exist that are environmentally acceptable and economically viable. A new method for converting sulfur dioxide to elemental sulfur by a cyclic process involving calcium sulfide and calcium sulfate without generating solid wastes has been developed. In this process, calcium sulfate pellets as the starting raw material are reduced by a suitable reducing agent such as hydrogen to produce calcium sulfide pellets, which are used to reduce sulfur dioxide producing elemental sulfur vapor and calcium sulfate. The latter is then reduced to regenerate calcium sulfide. Thermodynamic analysis and experimental results indicated that the CaS-SO2 reaction produces mainly sulfur vapor and solid calcium sulfate and that the gaseous product from the CaSO4-H2 reaction is mainly water vapor. The rates of the two reactions are reasonably rapid in the temperature range 1000-1100 K, and, importantly, the physical strengths and reactivities of the pellets are maintained largely unchanged up to the tenth cycle, the last cycle tested in this work. Sulfur dioxide-containing streams from certain sources, such as the regenerator off-gas from an integrated gasification combined cycle desulfurization unit and new sulfide smelting plants, contain much higher partial pressures of SO2. In these cases, the rate of the first reaction is expected to be proportionally higher than in the test conditions reported in this paper.

Nitrogen dioxide and kerosene-flame soot calibration of photoacoustic instruments for measurement of light absorption by aerosols

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

Arnott, W. Patrick; Moosmu''ller, Hans; Walker, John W.

2000-12-01

A nitrogen dioxide calibration method is developed to evaluate the theoretical calibration for a photoacoustic instrument used to measure light absorption by atmospheric aerosols at a laser wavelength of 532.0 nm. This method uses high concentrations of nitrogen dioxide so that both a simple extinction and the photoacoustically obtained absorption measurement may be performed simultaneously. Since Rayleigh scattering is much less than absorption for the gas, the agreement between the extinction and absorption coefficients can be used to evaluate the theoretical calibration, so that the laser gas spectra are not needed. Photoacoustic theory is developed to account for strong absorptionmore » of the laser beam power in passage through the resonator. Findings are that the photoacoustic absorption based on heat-balance theory for the instrument compares well with absorption inferred from the extinction measurement, and that both are well within values represented by published spectra of nitrogen dioxide. Photodissociation of nitrogen dioxide limits the calibration method to wavelengths longer than 398 nm. Extinction and absorption at 532 and 1047 nm were measured for kerosene-flame soot to evaluate the calibration method, and the single scattering albedo was found to be 0.31 and 0.20 at these wavelengths, respectively.« less

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

PubMed

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

2010-10-15

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

Observed changes in soyabean growth and seed yield from Albutilon theophrasti competition as a function of carbon dioxide concentration

USDA-ARS?s Scientific Manuscript database

Soybean (Glycine max) was grown at ambient and at projected levels of atmospheric carbon dioxide (+250 µmol mol-1 above ambient) with and without the presence of a weed (velvetleaf, Albutilon theophrasti Medic.) to quantify the potential effect of rising atmospheric carbon dioxide concentration [CO2...

Hydrodynamic Controls on Carbon Dioxide Efflux from Inland Waters

NASA Astrophysics Data System (ADS)

Long, H. E.; Waldron, S.; Hoey, T.; Newton, J.; Quemin, S.

2013-12-01

Intensive research has been undertaken on carbon dioxide efflux from lakes, estuaries and oceans, but much less attention has been given to rivers and streams, especially lower order streams. River systems are often over-saturated with carbon dioxide and so tend to act as sources of carbon dioxide to the atmosphere. It has been thought that rivers act as pipes carrying this terrestrial carbon to the oceans. However, recent studies have shown that a significant amount of the carbon is reprocessed within the system in a series of transformations and losses. Fluvial evasion of carbon dioxide is now recognised to be a significant component of carbon cycles, however the factors controlling carbon dioxide efflux and its magnitude remain poorly understood and quantified. This research aims to quantify, and better understand the controls on, freshwater carbon dioxide evasion. Data are presented here from field measurements that commenced in Sept 2013 in two contrasting Scottish rivers: the River Kelvin which has a large (335 km.sq) part-urban catchment with predominantly non-peat soils and Drumtee Water, a small (9.6 km.sq) rural catchment of peat soils and agricultural land. Using a floating chamber with the headspace connected to an infrared gas analyser to measure changes in carbon dioxide concentration, efflux rates from 0.22 - 47.4 μmol CO2/m.sq/sec were measured, these close to the middle of the range of previously reported values. At one site on the River Kelvin in May 2013 an influx of -0.61 - -3.53 μmol CO2/m.sq/sec was recorded. Whereas previous research finds carbon dioxide efflux to increase with decreasing river size and a more organic-rich soil catchment, here the controls on carbon dioxide evasion are similar across the contrasting catchments. Carbon dioxide evasion shows seasonality, with maximum fluxes in the summer months being up to twice as high as the winter maxima. Linear regression demonstrates that evasion increases with increased flow velocity, water surface disturbance indicated by Froude number, and turbulent mixing indicated by Reynolds number. Similar relationships with season, flow velocity and turbulence have been reported previously, but there is little known about the mechanisms involved. When comparing spot carbon dioxide efflux measurements to river stage time series data, carbon dioxide efflux is more sensitive to an increase in stage at more turbulent measurement points. Further investigation of the mechanisms will be obtained by measurement of DIC concentration and isotopic composition to assess the controls of carbon source versus degassing, and the analysis of the interactions between hydraulic and seasonal controls and carbon dioxide fluxes extended.

Life support system cost study: Addendum to cost analysis of carbon dioxide concentrators

NASA Technical Reports Server (NTRS)

Yakut, M. M.

1973-01-01

New cost data are presented for the Hydrogen-Depolarized Carbon Dioxide Concentrator (HDC), based on modifying the concentrator to delete the quick disconnect valves and filters included in the system model defined in MDC-G4631. System description, cost data and a comparison between CO2 concentrator costs are presented.

Method to prevent sulfur accumulation in membrane electrode assembly

DOEpatents

Steimke, John L; Steeper, Timothy J; Herman, David T

2014-04-29

A method of operating a hybrid sulfur electrolyzer to generate hydrogen is provided that includes the steps of providing an anolyte with a concentration of sulfur dioxide, and applying a current. During steady state generation of hydrogen a plot of applied current density versus concentration of sulfur dioxide is below a boundary line. The boundary line may be linear and extend through the origin of the graph with a slope of 0.001 in which the current density is measured in mA/cm2 and the concentration of sulfur dioxide is measured in moles of sulfur dioxide per liter of anolyte.

Saturation sampling for spatial variation in multiple air pollutants across an inversion-prone metropolitan area of complex terrain

PubMed Central

2014-01-01

Background Characterizing intra-urban variation in air quality is important for epidemiological investigation of health outcomes and disparities. To date, however, few studies have been designed to capture spatial variation during select hours of the day, or to examine the roles of meteorology and complex terrain in shaping intra-urban exposure gradients. Methods We designed a spatial saturation monitoring study to target local air pollution sources, and to understand the role of topography and temperature inversions on fine-scale pollution variation by systematically allocating sampling locations across gradients in key local emissions sources (vehicle traffic, industrial facilities) and topography (elevation) in the Pittsburgh area. Street-level integrated samples of fine particulate matter (PM2.5), black carbon (BC), nitrogen dioxide (NO2), sulfur dioxide (SO2), and ozone (O3) were collected during morning rush and probable inversion hours (6-11 AM), during summer and winter. We hypothesized that pollution concentrations would be: 1) higher under inversion conditions, 2) exacerbated in lower-elevation areas, and 3) vary by season. Results During July - August 2011 and January - March 2012, we observed wide spatial and seasonal variability in pollution concentrations, exceeding the range measured at regulatory monitors. We identified elevated concentrations of multiple pollutants at lower-elevation sites, and a positive association between inversion frequency and NO2 concentration. We examined temporal adjustment methods for deriving seasonal concentration estimates, and found that the appropriate reference temporal trend differs between pollutants. Conclusions Our time-stratified spatial saturation approach found some evidence for modification of inversion-concentration relationships by topography, and provided useful insights for refining and interpreting GIS-based pollution source indicators for Land Use Regression modeling. PMID:24735818

Saturation sampling for spatial variation in multiple air pollutants across an inversion-prone metropolitan area of complex terrain.

PubMed

Shmool, Jessie Lc; Michanowicz, Drew R; Cambal, Leah; Tunno, Brett; Howell, Jeffery; Gillooly, Sara; Roper, Courtney; Tripathy, Sheila; Chubb, Lauren G; Eisl, Holger M; Gorczynski, John E; Holguin, Fernando E; Shields, Kyra Naumoff; Clougherty, Jane E

2014-04-16

Characterizing intra-urban variation in air quality is important for epidemiological investigation of health outcomes and disparities. To date, however, few studies have been designed to capture spatial variation during select hours of the day, or to examine the roles of meteorology and complex terrain in shaping intra-urban exposure gradients. We designed a spatial saturation monitoring study to target local air pollution sources, and to understand the role of topography and temperature inversions on fine-scale pollution variation by systematically allocating sampling locations across gradients in key local emissions sources (vehicle traffic, industrial facilities) and topography (elevation) in the Pittsburgh area. Street-level integrated samples of fine particulate matter (PM2.5), black carbon (BC), nitrogen dioxide (NO2), sulfur dioxide (SO2), and ozone (O3) were collected during morning rush and probable inversion hours (6-11 AM), during summer and winter. We hypothesized that pollution concentrations would be: 1) higher under inversion conditions, 2) exacerbated in lower-elevation areas, and 3) vary by season. During July - August 2011 and January - March 2012, we observed wide spatial and seasonal variability in pollution concentrations, exceeding the range measured at regulatory monitors. We identified elevated concentrations of multiple pollutants at lower-elevation sites, and a positive association between inversion frequency and NO2 concentration. We examined temporal adjustment methods for deriving seasonal concentration estimates, and found that the appropriate reference temporal trend differs between pollutants. Our time-stratified spatial saturation approach found some evidence for modification of inversion-concentration relationships by topography, and provided useful insights for refining and interpreting GIS-based pollution source indicators for Land Use Regression modeling.

Decreased atmospheric sulfur deposition across the southeastern U.S.: When will watersheds release stored sulfate?

USGS Publications Warehouse

Rice, Karen C.; Scanlon, Todd M.; Lynch, Jason A.; Cosby, Bernard J.

2014-01-01

Emissions of sulfur dioxide (SO2) to the atmosphere lead to atmospheric deposition of sulfate (SO42-), which is the dominant strong acid anion causing acidification of surface waters and soils in the eastern United States (U.S.). Since passage of the Clean Air Act and its Amendments, atmospheric deposition of SO2 in this region has declined by over 80%, but few corresponding decreases in stream-water SO42- concentrations have been observed in unglaciated watersheds. We calculated SO42- mass balances for 27 forested, unglaciated watersheds from Pennsylvania to Georgia, by using total atmospheric deposition (wet plus dry) as input. Many of these watersheds still retain SO42-, unlike their counterparts in the northeastern U.S. and southern Canada. Our analysis showed that many of these watersheds should convert from retaining to releasing SO42- over the next two decades. The specific years when the watersheds crossover from retaining to releasing SO42- correspond to a general geographical pattern of later net watershed release from north to south. The single most important variable that explained the crossover year was the runoff ratio, defined as the ratio of annual mean stream discharge to precipitation. Percent clay content and mean soil depth were secondary factors in predicting crossover year. The conversion of watersheds from net SO42- retention to release anticipates more widespread reductions in stream-water SO42- concentrations in this region.

Temporal Characterisation of Ground-level Ozone Concentration in Klang Valley

NASA Astrophysics Data System (ADS)

Izzah Mohamad Hashim, Nur; Noor, Norazian Mohamed; Yasina Yusof, Sara

2018-03-01

In Malaysia, ground-level ozone (O3) is one of the most significant air pollutants due to the increasing sources of ozone precursors. Hence, the surface O3 concentration should have received substantial attention because of its negative effects to human health, vegetation and the environment. In this study, hourly air pollutants dataset (i.e O3, Carbon monoxide (CO), Nitrogen dioxide (NO2), Particulate matter (PM10), Non-methane hydrocarbon (NmHC), Sulphur dioxide (SO2)) and weather parameters (i.e. wind speed (WS), wind direction (WD), temperature (T), ultraviolet B (UVB)) for ten years period (2003-2012) in Klang Valley were selected for analysis in this study. Two monitoring stations were selected that are Petaling Jaya and Shah Alam. The aim of the study is to determine the diurnal variations of O3 concentrations according to the seasonal monsoon and the correlation between the ground-level O3 concentration and others parameter. A high concentration of ground-level O3 was observed during the first transition (April to May) for both of the stations. While at a low surface, O3 concentration was found out during the southwest monsoon within June to September. Pearson correlation was used to find the correlation between the O3 concentration and all other pollutants and weather parameters. Most of the relationship between O3concentrationswas positively correlated with NO2 and negative relationship was found out with NMHC. These results were expected since these pollutants are known as the O3 precursors. Besides that, O3 concentration and its precursors show a positive significant correlation with all meteorological factors except for relative humidity.

Technology advancement of the electrochemical CO2 concentrating process

NASA Technical Reports Server (NTRS)

Schubert, F. H.; Heppner, D. B.; Hallick, T. M.; Woods, R. R.

1979-01-01

Two multicell, liquid-cooled, advanced electrochemical depolarized carbon dioxide concentrator modules were fabricated. The cells utilized advanced, lightweight, plated anode current collectors, internal liquid cooling and lightweight cell frames. Both were designed to meet the carbon dioxide removal requirements of one-person, i.e., 1.0 kg/d (2.2 lb/d).

China's air pollution reduction efforts may result in an increase in surface ozone levels in highly polluted areas.

PubMed

Anger, Annela; Dessens, Olivier; Xi, Fengming; Barker, Terry; Wu, Rui

2016-03-01

China, as a fast growing fossil-fuel-based economy, experiences increasing levels of air pollution. To tackle air pollution, China has taken the first steps by setting emission-reduction targets for nitrogen oxides (NO x ) and sulphur dioxide (SO2) in the 11th and 12th Five Year Plans. This paper uses two models-the Energy-Environment-Economy Model at the Global level (E3MG) and the global Chemistry Transport Model pTOMCAT-to test the effects of these policies. If the policy targets are met, then the maximum values of 32 % and 45 % reductions below 'business as usual' in the monthly mean NO x and SO2 concentrations, respectively, will be achieved in 2015. However, a decrease in NO x concentrations in some highly polluted areas of East, North-East and South-East China can lead to up to a 10% increase in the monthly mean concentrations in surface ozone in 2015. Our study demonstrates an urgent need for the more detailed analysis of the impacts and designs of air pollution reduction guidelines for China.

Investigation into the ring-substituted polyanilines and their application for the detection and adsorption of sulfur dioxide

PubMed Central

Tian, Yuhong; Qu, Ke; Zeng, Xiangqun

2017-01-01

It has been demonstrated in this study that the substituents on the monomer aniline benzene ring are able to introduce the significant differences to the resulting polyaniline’s collective properties. We systematically evaluated the structural perturbation effects of two substituents (methyl and methoxy) of aniline monomer through the electrochemical method. Our results showed that the methoxy group induces the less structural perturbation than the methyl counterpart, because of its partial double bond restriction. The morphologies are different for the polyaniline and the ring-substituted polyanilines, in which substituted polyanilines feature the larger porosities with the addition of these side groups. The influential effects of the methoxy side group have been further illustrated and amplified by its superior sensing performance towards the environmentally-significant sulfur dioxide gas, evaluated through the construction of the quartz crystal microbalance (QCM)-based gas sensor with these polyaniline materials. The as-constructed gas sensor’s sensitivity, selectivity and stability in terms of its SO2 responses have been evaluated in details. The methoxy-substituted polyaniline was tested to show the unique gas sensing properties for the sulfur dioxide at the low concentrations (50–250 ppm) and function as the adsorbing material at the high concentrations (500–1250 ppm). Thus it can be used both as sensing material as well as a novel filter and/or storage reservoir for the removal of sulfur dioxide pollutant from the environments. PMID:29033497

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

PubMed

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.

Evaluation of sulfur dioxide emissions from explosive volcanism: the 1982-1983 eruptions of Galunggung, Java, Indonesia

USGS Publications Warehouse

Bluth, G.J.S.; Casadevall, T.J.; Schnetzler, C.C.; Doiron, S.D.; Walter, Louis S.; Krueger, A.J.; Badruddin, M.

1994-01-01

Galunggung volcano, Java, awoke from a 63-year quiescence in April 1982, and erupted sporadically through January 1983. During its most violent period from April to October, the Cikasasah Volcano Observatory reported 32 large and 56 moderate to small eruptions. From April 5 through September 19 the Total Ozone Mapping Spectrometer (TOMS), carried on NASA's Nimbus-7 satellite, detected and measured 24 different sulfur dioxide clouds; an estimated 1730 kilotons (kt) of SO2 were outgassed by these explosive eruptions. The trajectories, and rapid dispersion rates, of the SO2 clouds were consistent with injection altitudes below the tropopause. An additional 300 kt of SO2 were estimated to have come from 64 smaller explosive eruptions, based on the detection limit of the TOMS instrument. For the first time, an extended period of volcanic activity was monitored by remote sensing techniques which enabled observations of both the entire SO2 clouds produced by large explosive eruptions (using TOMS), and the relatively lower levels of SO2 emissions during non-explosive outgassing (using the Correlation Spectrometer, or COSPEC). Based on COSPEC measurements from August 1982 to January 1983, and on the relationship between explosive and non-explosive degassing, approximately 400 kt of SO2 were emitted during non-explosive activity. The total sulfur dioxide outgassed from Galunggung volcano from April 1982 to January 1983 is calculated to be 2500 kt (?? 30%) from both explosive and non-explosive activity. While Galunggung added large quantities of sulfur dioxide to the atmosphere, its sporadic emissions occurred in relatively small events distributed over several months, and reached relatively low altitudes, and are unlikely to have significantly affected aerosol loading of the stratosphere in 1982 by volcanic activity. ?? 1994.

Florida Harvester Ant Nest Architecture, Nest Relocation and Soil Carbon Dioxide Gradients

PubMed Central

Tschinkel, Walter R.

2013-01-01

Colonies of the Florida harvester ant, Pogonomyrmex badius, excavate species-typical subterranean nests up the 3 m deep with characteristic vertical distribution of chamber area/shape, spacing between levels and vertical arrangement of the ants by age and brood stage. Colonies excavate and occupy a new nest about once a year, and doing so requires that they have information about the depth below ground. Careful excavation and mapping of vacated and new nests revealed that there was no significant difference between the old and new nests in any measure of nest size, shape or arrangement. Colonies essentially built a replicate of the just-vacated nest (although details differed), and they did so in less than a week. The reason for nest relocation is not apparent. Tschinkel noted that the vertical distribution of chamber area, worker age and brood type was strongly correlated to the soil carbon dioxide gradient, and proposed that this gradient serves as a template for nest excavation and vertical distribution. To test this hypothesis, the carbon dioxide gradient of colonies that were just beginning to excavate a new nest was eliminated by boring 6 vent holes around the forming nest, allowing the soil CO2 to diffuse into the atmosphere and eliminating the gradient. Sadly, neither the nest architecture nor the vertical ant distribution of vented nests differed from either unvented control or from their own vacated nest. In a stronger test, workers excavated a new nest under a reversed carbon dioxide gradient (high concentration near the surface, low below). Even under these conditions, the new and old nests did not differ significantly, showing that the soil carbon dioxide gradient does not serve as a template for nest construction or vertical worker distribution. The possible importance of soil CO2 gradients for soil-dwelling animals is discussed. PMID:23555829

Epoxide-functionalization of polyethyleneimine for synthesis of stable carbon dioxide adsorbent in temperature swing adsorption

PubMed Central

Choi, Woosung; Min, Kyungmin; Kim, Chaehoon; Ko, Young Soo; Jeon, Jae Wan; Seo, Hwimin; Park, Yong-Ki; Choi, Minkee

2016-01-01

Amine-containing adsorbents have been extensively investigated for post-combustion carbon dioxide capture due to their ability to chemisorb low-concentration carbon dioxide from a wet flue gas. However, earlier studies have focused primarily on the carbon dioxide uptake of adsorbents, and have not demonstrated effective adsorbent regeneration and long-term stability under such conditions. Here, we report the versatile and scalable synthesis of a functionalized-polyethyleneimine (PEI)/silica adsorbent which simultaneously exhibits a large working capacity (2.2 mmol g−1) and long-term stability in a practical temperature swing adsorption process (regeneration under 100% carbon dioxide at 120 °C), enabling the separation of concentrated carbon dioxide. We demonstrate that the functionalization of PEI with 1,2-epoxybutane reduces the heat of adsorption and facilitates carbon dioxide desorption (>99%) during regeneration compared with unmodified PEI (76%). Moreover, the functionalization significantly improves long-term adsorbent stability over repeated temperature swing adsorption cycles due to the suppression of urea formation and oxidative amine degradation. PMID:27572662

Photocatalytic degradation of acetaminophen in modified TiO2 under visible irradiation.

PubMed

Dalida, Maria Lourdes P; Amer, Kristine Marfe S; Su, Chia-Chi; Lu, Ming-Chun

2014-01-01

This study investigated the photocatalytic degradation of acetaminophen (ACT) in synthetic titanium dioxide (TiO2) solution under a visible light (λ >440 nm). The TiO2 photocatalyst used in this study was synthesized via sol-gel method and doped with potassium aluminum sulfate (KAl(SO4)2) and sodium aluminate (NaAlO2). The influence of some parameters on the degradation of acetaminophen was examined, such as initial pH, photocatalyst dosage, and initial ACT concentration. The optimal operational conditions were also determined. Results showed that synthetic TiO2 catalysts presented mainly as anatase phase and no rutile phase was observed. The results of photocatalytic degradation showed that LED alone degraded negligible amount of ACT but with the presence of TiO2/KAl(SO4)2, 95% removal of 0.10-mM acetaminophen in 540-min irradiation time was achieved. The synthetic TiO2/KAl(SO4)2 presented better photocatalytic degradation of acetaminophen than commercially available Degussa P-25. The weak crystallinity of synthesized TiO2/NaAlO2 photocatalyst showed low photocatalytic degradation than TiO2/KAl(SO4)2. The optimal operational conditions were obtained in pH 6.9 with a dose of 1.0 g/L TiO2/KAl(SO4)2 at 30 °C. Kinetic study illustrated that photocatalytic degradation of acetaminophen fits well in the pseudo-first order model. Competitive reactions from intermediates affected the degradation rate of ACT, and were more obvious as the initial ACT concentration increased.

40 CFR 74.22 - Actual SO2 emissions rate.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 40 Protection of Environment 16 2010-07-01 2010-07-01 false Actual SO2 emissions rate. 74.22... (CONTINUED) SULFUR DIOXIDE OPT-INS Allowance Calculations for Combustion Sources § 74.22 Actual SO2 emissions... actual SO2 emissions rate shall be 1985. (2) For combustion sources that commenced operation after...

Influence of local and regional Mediterranean meteorology on SO₂ ground-level concentrations in SE Spain.

PubMed

Santacatalina, Milagros; Carratalá, Adoración; Mantilla, Enrique

2011-06-01

This work presents the results of a 4-year study on sulfur dioxide (SO(2)) ground-level concentrations in an area of southeastern Spain, the L'Alacantí region, where the cement industry is important and coke use extends to other industries as well. The main source of SO(2) emissions in the area was found to be a the Lepold cement plant (one of the two cement plants in the area). The high levels of SO(2) probably extend back to 1920 when this plant began operations. Both local and Mediterranean-scale meteorological processes influence the SO(2) ground-level concentration and together explain the dispersion dynamics of this pollutant. The location and topography of the study zone result in NW Atlantic advections and E-SE sea breezes being the dominant atmospheric circulation patterns in the area. Under stable meteorological conditions, minor local circulations are also relevant to the SO(2) concentration levels. The high frequency of local circulations determines a concentration pattern that changes during the day, with impacts occurring preferentially in a W-NW direction from the source at midday (sea breeze and strong thermal mixture), and in a SE direction at night. This causes the SO(2) concentrations to present well-defined diurnal cycles with well-differentiated shapes depending on the location of the sampling station relative to the source. The dependence of SO(2) 10 min levels on the wind origin and speed throughout the day has been evaluated by studying statistical parameters including P95, P50 and arithmetic mean. Exceedances occur under specific dispersion conditions at distances less than 1 km from the source. However, the source is traceable at larger distances and the levels are higher than typical urban ones. P95 was used as an estimator of the occurrence of larger levels or impacts. Leeward of NW winds and the source, at night and in early morning, P95 levels are comprised between 30 and 55 µg m(-3). In contrast, with SE winds and at midday, P95 levels stay at 17 µg m(-3). The same P95 was obtained for winds lower than 5 m s(-1), which represent 89% of the winds in the area. However, stronger winds can have P95 levels above 125 µg m(-3).

The concentration-response relation between air pollution and daily deaths.

PubMed Central

Schwartz, J; Ballester, F; Saez, M; Pérez-Hoyos, S; Bellido, J; Cambra, K; Arribas, F; Cañada, A; Pérez-Boillos, M J; Sunyer, J

2001-01-01

Studies on three continents have reported associations between various measures of airborne particles and daily deaths. Sulfur dioxide has also been associated with daily deaths, particularly in Europe. Questions remain about the shape of those associations, particularly whether there are thresholds at low levels. We examined the association of daily concentrations of black smoke and SO(2) with daily deaths in eight Spanish cities (Barcelona, Bilbao, Castellón, Gijón, Oviedo, Valencia, Vitoria, and Zaragoza) with different climates and different environmental and social characteristics. We used nonparametric smoothing to estimate the shape of the concentration-response curve in each city and combined those results using a metasmoothing technique developed by Schwartz and Zanobetti. We extended their method to incorporate random variance components. Black smoke had a nearly linear association with daily deaths, with no evidence of a threshold. A 10 microg/m(3) increase in black smoke was associated with a 0.88% increase in daily deaths (95% confidence interval, 0.56%-1.20%). SO(2) had a less plausible association: Daily deaths increased at very low concentrations, but leveled off and then decreased at higher concentrations. These findings held in both one- and two-pollutant models and held whether we optimized our weather and seasonal model in each city or used the same smoothing parameters in each city. We conclude that the association with particle levels is more convincing than for SO(2), and without a threshold. Linear models provide an adequate estimation of the effect of particulate air pollution on mortality at low to moderate concentrations. PMID:11675264

Validation of double-pulse 1572 nm integrated path differential absorption lidar measurement of carbon dioxide

NASA Astrophysics Data System (ADS)

Du, Juan; Liu, Jiqiao; Bi, Decang; Ma, Xiuhua; Hou, Xia; Zhu, Xiaolei; Chen, Weibiao

2018-04-01

A ground-based double-pulse 1572 nm integrated path differential absorption (IPDA) lidar was developed for carbon dioxide (CO2) column concentrations measurement. The lidar measured the CO2 concentrations continuously by receiving the scattered echo signal from a building about 1300 m away. The other two instruments of TDLAS and in-situ CO2 analyzer measured the CO2 concentrations on the same time. A CO2 concentration measurement of 430 ppm with 1.637 ppm standard error was achieved.

Distributions of Trace Gases and Aerosols during the Dry Biomass Burning Season in Southern Africa

NASA Technical Reports Server (NTRS)

Sinha, Parikhit; Hobbs, Peter V.; Yokelson, Robert J.; Blake, Donald R.; Gao, Song; Kirchstetter, Thomas W.

2003-01-01

Vertical profiles in the lower troposphere of temperature, relative humidity, sulfur dioxide (SO2), ozone (O3), condensation nuclei (CN), and carbon monoxide (CO), and horizontal distributions of twenty gaseous and particulate species, are presented for five regions of southern Africa during the dry biomass burning season of 2000. The regions are the semiarid savannas of northeast South Africa and northern Botswana, the savanna-forest mosaic of coastal Mozambique, the humid savanna of southern Zambia, and the desert of western Namibia. The highest average concentrations of carbon dioxide (CO2), CO, methane (CH4), O3, black particulate carbon, and total particulate carbon were in the Botswana and Zambia sectors (388 and 392 ppmv, 369 and 453 ppbv, 1753 and 1758 ppbv, 79 and 88 ppbv, 2.6 and 5.5 micrograms /cubic meter and 13.2 and 14.3 micrograms/cubic meter). This was due to intense biomass burning in Zambia and surrounding regions. The South Africa sector had the highest average concentrations of SO2, sulfate particles, and CN (5.1 ppbv, 8.3 micrograms/cubic meter, and per 6400 cubic meter , respectively), which derived from biomass burning and electric generation plants and mining operations within this sector. Air quality in the Mozambique sector was similar to the neighboring South Africa sector. Over the arid Namibia sector there were polluted layers aloft, in which average SO2, O3, and CO mixing ratios (1.2 ppbv, 76 ppbv, and 3 10 ppbv, respectively) were similar to those measured over the other more polluted sectors. This was due to transport of biomass smoke from regions of widespread savanna burning in southern Angola. Average concentrations over all sectors of CO2 (386 +/- 8 ppmv), CO (261 +/- 81 ppbv), SO2 (2.5 +/- 1.6 ppbv), O3 (64 +/- 13 ppbv), black particulate carbon (2.3 +/- 1.9 microgram/cubic meter), organic particulate carbon (6.2 +/- 5.2 microgram/cubic meter), total particle mass (26.0 +/- 4.7 microgram/cubic meter), and potassium particles (0.4 +- 0.1 microgram/cubic meter) were comparable to those in polluted, urban air. Since the majority of the measurements in this study were obtained in locations well removed from industrial sources of pollution, the high average concentrations of pollutants reflect the effects of widespread biomass burning. On occasions, relatively thin (-0.5 km) layers of remarkably clean air were located at -3 km above mean sea level, sandwiched between heavily polluted air. The data presented here can be used for inputs to and validation of regional and global atmospheric chemical models.

Distributions of trace gases and aerosols during the dry biomass burning season in southern Africa

NASA Astrophysics Data System (ADS)

Sinha, Parikhit; Hobbs, Peter V.; Yokelson, Robert J.; Blake, Donald R.; Gao, Song; Kirchstetter, Thomas W.

2003-09-01

Vertical profiles in the lower troposphere of temperature, relative humidity, sulfur dioxide (SO2), ozone (O3), condensation nuclei (CN), and carbon monoxide (CO), and horizontal distributions of twenty gaseous and particulate species, are presented for five regions of southern Africa during the dry biomass burning season of 2000. The regions are the semiarid savannas of northeast South Africa and northern Botswana, the savanna-forest mosaic of coastal Mozambique, the humid savanna of southern Zambia, and the desert of western Namibia. The highest average concentrations of carbon dioxide (CO2), CO, methane (CH4), O3, black particulate carbon, and total particulate carbon were in the Botswana and Zambia sectors (388 and 392 ppmv, 369 and 453 ppbv, 1753 and 1758 ppbv, 79 and 88 ppbv, 2.6 and 5.5 μg m-3, and 13.2 and 14.3 μg m-3). This was due to intense biomass burning in Zambia and surrounding regions. The South Africa sector had the highest average concentrations of SO2, sulfate particles, and CN (5.1 ppbv, 8.3 μg m-3, and 6400 cm-3, respectively), which derived from biomass burning and electric generation plants and mining operations within this sector. Air quality in the Mozambique sector was similar to the neighboring South Africa sector. Over the arid Namibia sector there were polluted layers aloft, in which average SO2, O3, and CO mixing ratios (1.2 ppbv, 76 ppbv, and 310 ppbv, respectively) were similar to those measured over the other more polluted sectors. This was due to transport of biomass smoke from regions of widespread savanna burning in southern Angola. Average concentrations over all sectors of CO2 (386 ± 8 ppmv), CO (261 ± 81 ppbv), SO2 (2.5 ± 1.6 ppbv), O3 (64 ± 13 ppbv), black particulate carbon (2.3 ± 1.9 μg m-3), organic particulate carbon (6.2 ± 5.2 μg m-3), total particle mass (26.0 ± 4.7 μg m-3), and potassium particles (0.4 ± 0.1 μg m-3) were comparable to those in polluted, urban air. Since the majority of the measurements in this study were obtained in locations well removed from industrial sources of pollution, the high average concentrations of pollutants reflect the effects of widespread biomass burning. On occasions, relatively thin (˜0.5 km) layers of remarkably clean air were located at ˜3 km above mean sea level, sandwiched between heavily polluted air. The data presented here can be used for inputs to and validation of regional and global atmospheric chemical models.

Photosynthesis in tropical cover crop legumes influenced by irradiance, external carbon dioxide concentration and temperature

USDA-ARS?s Scientific Manuscript database

In plantation crops perennial tropical legumes are grown as understory plants, receive limited irradiance, and are subjected to elevated levels of CO2 and temperature. Independent short-term effects of photosynthetic photon flux density (PPFD), external carbon dioxide concentration [CO2] and temper...

Feasibility of measuring dissolved carbon dioxide based on head space partial pressures

USGS Publications Warehouse

Watten, B.J.; Boyd, C.E.; Schwartz, M.F.; Summerfelt, S.T.; Brazil, B.L.

2004-01-01

We describe an instrument prototype that measures dissolved carbon dioxide (DC) without need for standard wetted probe membranes or titration. DC is calculated using Henry's Law, water temperature, and the steady-state partial pressure of carbon dioxide that develops within the instrument's vertical gas-liquid contacting chamber. Gas-phase partial pressures were determined with either an infrared detector (ID) or by measuring voltage developed by a pH electrode immersed in an isolated sodium carbonate solution (SC) sparged with recirculated head space gas. Calculated DC concentrations were compared with those obtained by titration over a range of DC (2, 4, 8, 12, 16, 20, 24, and 28mg/l), total alkalinity (35, 120, and 250mg/l as CaCO3), total dissolved gas pressure (-178 to 120 mmHg), and dissolved oxygen concentrations (7, 14, and 18 mg/l). Statistically significant (P < 0.001) correlations were established between head space (ID) and titrimetrically determined DC concentrations (R2 = 0.987-0.999, N = 96). Millivolt and titrimetric values from the SC solution tests were also correlated (P < 0.001, R 2 = 0.997, N = 16). The absolute and relative error associated with the use of the ID and SC solution averaged 0.9mg/l DC and 7.0% and 0.6 mg/l DC and 9.6%, respectively. The precision of DC estimates established in a second test series was good; coefficients of variation (100(SD/mean)) for the head space (ID) and titration analyses were 0.99% and 1.7%. Precision of the SC solution method was 1.3%. In a third test series, a single ID was coupled with four replicate head space units so as to permit sequential monitoring (15 min intervals) of a common water source. Here, appropriate gas samples were secured using a series of solenoid valves (1.6 mm bore) activated by a time-based controller. This system configuration reduced the capital cost per sample site from US$ 2695 to 876. Absolute error averaged 2.9, 3.1, 3.7, and 2.7 mg/ l for replicates 1-4 (N = 36) during a 21-day test period (DC range, 36-40 mg/l). The ID meter was then modified so as to provide for DO as well as DC measurements across components of an intensive fish production system. ?? 2003 Elsevier B.V. All rights reserved.

Ore sintering flue gas desulfurization and its resoureilization by using pyrolusite

NASA Astrophysics Data System (ADS)

Li, S. E.; Long, Z. G.; Wu, F. Z.; Li, H. Y.; Cui, T. M.; Zhou, X. Z.

2017-11-01

Flue gas desulfurization (FGD) has been implemented for sulfur dioxide gas emission reduction by pyrolusite in iron ore sintering. However, the mechanism of SO2 reduction through FGD is still not fully clear. And in present work, the effects of operating conditions on desulfurization rate and Mn2+ leaching rate of pyrolusite were investigated. Six hours later, the desulfurization rate and Mn2+ leaching rate all can be higher than 70%. And a higher absorption temperature was good for desulfurization rate, while a middle temperature was good for Mn2+ leaching rate. A higher manganese ore granularity and SO2 concentration were good for desulfurization rate and Mn2+ leaching rate. However, a higher liquid-solid rate was only good for desulfurization rate, but Mn2+ leaching rate. The results demonstrate that the pyrolusite is a kind of very promising adsorbent in industrial flue gas desulfurization application due to its low cost and good desulfurization capacity.

The Role of Sulfur Dioxide in Stratospheric Aerosol Formation Evaluated Using In-Situ Measurements in the Tropical Lower Stratosphere

PubMed Central

Rollins, A. W.; Thornberry, T. D.; Watts, L. A.; Yu, P.; Rosenlof, K. H.; Mills, M.; Baumann, E.; Giorgetta, F. R.; Bui, T. V.; Höpfner, M.; Walker, K. A.; Boone, C.; Bernath, P. F.; Colarco, P. R.; Newman, P. A.; Fahey, D. W.; Gao, R. S.

2017-01-01

Stratospheric aerosols (SAs) are a variable component of the Earth's albedo that may be intentionally enhanced in the future to offset greenhouse gases (geoengineering). The role of tropospheric-sourced sulfur dioxide (SO2) in maintaining background SAs has been debated for decades without in-situ measurements of SO2 at the tropical tropopause to inform this issue. Here we clarify the role of SO2 in maintaining SAs by using new in-situ SO2 measurements to evaluate climate models and satellite retrievals. We then use the observed tropical tropopause SO2 mixing ratios to estimate the global flux of SO2 across the tropical tropopause. These analyses show that the tropopause background SO2 is about 5 times smaller than reported by the average satellite observations that have been used recently to test atmospheric models. This shifts the view of SO2 as a dominant source of SAs to a near-negligible one, possibly revealing a significant gap in the SA budget. PMID:29225384

40 CFR 60.46c - Emission monitoring for sulfur dioxide.

Code of Federal Regulations, 2011 CFR

2011-07-01

... potential SO2 emission rate of the fuel combusted, and the span value of the SO2 CEMS at the outlet from the SO2 control device shall be 50 percent of the maximum estimated hourly potential SO2 emission rate of... estimated hourly potential SO2 emission rate of the fuel combusted. (d) As an alternative to operating a...

Sulfur Dioxide State Implementation Plan (SIP) Checklist Guide

EPA Pesticide Factsheets

Tools, guidance, and examples to assist air quality agencies of non-attainment areas in developing plans to implement national ambient air quality standards (NAAQS), including the sulfur dioxide (SO2) air emissions standard.

Simultaneous removal of SO2 and NOx from flue gas by wet scrubbing using a urea solution.

PubMed

Li, Ge; Wang, Baodong; Xu, Wayne Qiang; Li, Yonglong; Han, Yifan; Sun, Qi

2018-03-27

Nitrogen oxides (NO x ) and sulfur dioxide (SO 2 ) are major air pollutants, so simultaneously removing them from gases emitted during fossil fuel combustion in stationary systems is important. Wet denitrification using urea is used for a wide range of systems. Additives have strong effects on wet denitrification using urea, and different mechanisms are involved and different effects found using different additives. In this study, the effects of different additives, initial urea concentrations, reaction temperatures, initial pH values, gas flow rates, and reaction times on the simultaneous desulfurization and denitrification efficiencies achieved using wet denitrification using urea were studied in single factor experiment. The optimum reaction conditions for desulfurization and denitrification were found. Desulfurization and denitrification efficiencies of 97.5% and 96.3%, respectively, were achieved at a KMnO 4 concentration 5 mmol/L, a reaction temperature of 70°C, initial urea solution pH 8, a urea concentration of 9%, and a gas flow rate of 40 L/h. The concentrations of the desulfurization and denitrification reaction products in the solution were determined. NO x was mainly transformed into N 2 , and the [Formula: see text] and [Formula: see text] concentrations in the solution became very low. The reactions involved in SO 2 and NO x removal using urea were analyzed from the thermodynamic viewpoint. Increasing the temperature was not conducive to the reactions but increased the rate constant, so an optimum temperature was determined. The simultaneous desulfurization and denitrification kinetics were calculated. The urea consumption and [Formula: see text], [Formula: see text], and [Formula: see text] generation reactions were all zero order. The [Formula: see text] generation rate was greater than the [Formula: see text] generation rate. The simultaneous desulfurization and denitrification process and mechanism were studied. The results provide reference data for performing flue gas desulfurization and denitrification in factories.

40 CFR Appendix A-4 to Part 60 - Test Methods 6 through 10B

Code of Federal Regulations, 2010 CFR

2010-07-01

... sources Method 6A—Determination of sulfur dioxide, moisture, and carbon dioxide emissions from fossil fuel... fossil fuel combustion sources Method 6C—Determination of Sulfur Dioxide Emissions From Stationary... with SO2 to form particulate sulfite and by reacting with the indicator. If free ammonia is present...

40 CFR Appendix A-4 to Part 60 - Test Methods 6 through 10B

Code of Federal Regulations, 2011 CFR

2011-07-01

... sources Method 6A—Determination of sulfur dioxide, moisture, and carbon dioxide emissions from fossil fuel... fossil fuel combustion sources Method 6C—Determination of Sulfur Dioxide Emissions From Stationary... with SO2 to form particulate sulfite and by reacting with the indicator. If free ammonia is present...

40 CFR Appendix A-4 to Part 60 - Test Methods 6 through 10B

Code of Federal Regulations, 2013 CFR

2013-07-01

... sources Method 6A—Determination of sulfur dioxide, moisture, and carbon dioxide emissions from fossil fuel... fossil fuel combustion sources Method 6C—Determination of Sulfur Dioxide Emissions From Stationary... with SO2 to form particulate sulfite and by reacting with the indicator. If free ammonia is present...

40 CFR Appendix A-4 to Part 60 - Test Methods 6 through 10B

Code of Federal Regulations, 2014 CFR

2014-07-01

... sources Method 6A—Determination of sulfur dioxide, moisture, and carbon dioxide emissions from fossil fuel... fossil fuel combustion sources Method 6C—Determination of Sulfur Dioxide Emissions From Stationary... reacting with SO2 to form particulate sulfite and by reacting with the indicator. If free ammonia is...

40 CFR Appendix A-4 to Part 60 - Test Methods 6 through 10B

Code of Federal Regulations, 2012 CFR

2012-07-01

... sources Method 6A—Determination of sulfur dioxide, moisture, and carbon dioxide emissions from fossil fuel... fossil fuel combustion sources Method 6C—Determination of Sulfur Dioxide Emissions From Stationary... with SO2 to form particulate sulfite and by reacting with the indicator. If free ammonia is present...

40 CFR 60.642 - Standards for sulfur dioxide.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 40 Protection of Environment 6 2011-07-01 2011-07-01 false Standards for sulfur dioxide. 60.642... Gas Processing: SO2 Emissions § 60.642 Standards for sulfur dioxide. (a) During the initial... reduction efficiency (Zi) to be determined from table 1 based on the sulfur feed rate (X) and the sulfur...

40 CFR 60.642 - Standards for sulfur dioxide.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 40 Protection of Environment 7 2012-07-01 2012-07-01 false Standards for sulfur dioxide. 60.642... Gas Processing: SO2 Emissions § 60.642 Standards for sulfur dioxide. (a) During the initial... reduction efficiency (Zi) to be determined from table 1 based on the sulfur feed rate (X) and the sulfur...

40 CFR 60.642 - Standards for sulfur dioxide.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 40 Protection of Environment 6 2010-07-01 2010-07-01 false Standards for sulfur dioxide. 60.642... Gas Processing: SO2 Emissions § 60.642 Standards for sulfur dioxide. (a) During the initial... reduction efficiency (Zi) to be determined from table 1 based on the sulfur feed rate (X) and the sulfur...

Associations between ambient air pollution and prevalence of stroke and cardiovascular diseases in 33 Chinese communities

NASA Astrophysics Data System (ADS)

Dong, Guang-Hui; Qian, Zhengmin (Min); Wang, Jing; Chen, Weiqing; Ma, Wenjun; Trevathan, Edwin; Xaverius, Pamela K.; DeClue, Richard; Wiese, Andrew; Langston, Marvin; Liu, Miao-Miao; Wang, Da; Ren, Wan-Hui

2013-10-01

Inconsistent results have been reported that long-term exposure to ambient air pollution contributes to the increased prevalence of stroke and cardiovascular diseases (CVDs). In order to examine whether the exposure to ambient air pollution was associated with the prevalence of stroke and CVDs among people living in a heavy industrial province of northeast China, we conducted a cross-sectional study of 24,845 Chinese adults, ages 18-74 years old, from 33 communities in the 11 districts of the three Northeastern Chinese Cities during 2009. Three-year (2006-2008) average concentrations of particles with an aerodynamic diameter ≤10 μm (PM10), sulfur dioxide (SO2), nitrogen dioxides (NO2), and Ozone (O3) were calculated from monitoring stations in each of the 11 districts. We used two-level logistic regressions models to examine the effects of yearly variations in exposure to each pollutant, controlling for important covariates. We found significant associations between PM10 and SO2 levels and stroke prevalence after accounting for important covariates: the adjusted odds ratio for stroke increased by 1.16 (95% confidence interval [CI], 1.03-1.30) per 19 μg m-3 increase in PM10, and 1.14 (95%CI, 1.01-1.29) per 20 μg m-3 increase in SO2, respectively. When stratified analysis by gender, these associations were significant only in men, but not in women. In conclusion, this study shows the association between long-term exposure to PM10 and SO2 and increased stroke prevalence, and the associations were more apparent in men than in women.

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

NASA Astrophysics Data System (ADS)

Liu, T.; Wang, X.; Hu, Q.; Deng, W.; Zhang, Y.; Ding, X.; Fu, X.; Bernard, F.; Zhang, Z.; Lü, S.; He, Q.; Bi, X.; Chen, J.; Sun, Y.; Yu, J.; Peng, P.; Sheng, G.; Fu, J.

2016-01-01

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.

Ambient air pollution and daily hospital admissions for mental disorders in Shanghai, China.

PubMed

Chen, Chen; Liu, Cong; Chen, Renjie; Wang, Weibing; Li, Weihua; Kan, Haidong; Fu, Chaowei

2018-02-01

Few studies have investigated the associations between ambient air pollution and mental disorders (MDs), especially in developing countries. We conducted a time-series study to explore the associations between six criteria air pollutants and daily hospital admissions for MDs in Shanghai, China, from 2013 to 2015. The MDs data were derived from the Shanghai Health Insurance System. We used over-dispersed, generalized additive models to estimate the associations after controlling for time trend, weather conditions, day of the week, and holidays. In addition, we evaluated the effect of modification by age, sex, and season. A total of 39,143 cases of hospital admissions for MDs were identified during the study period. A 10-μg/m 3 increase in 2-day, moving-average concentration of inhalable particulate matter, sulfur dioxide (SO 2 ), and carbon monoxide was significantly associated with increments of 1.27% [95% confidence interval (CI): 0.28%, 2.26%], 6.88% (95% CI, 2.75%, 11.00%), and 0.16% (95% CI: 0.02%, 0.30%) in daily hospital admissions for MDs, respectively. We observed positive but insignificant associations of fine particulate matter, nitrogen dioxide and ozone. The estimated association of SO 2 was relatively robust to the adjustment of simultaneous exposure to other pollutants. We found generally stronger associations of air pollutants with MDs in warm seasons than in cool seasons. There were no significant differences in the associations between different sex and age groups. This study suggested that short-term exposure to air pollution, especially to sulfur dioxide, was associated with increased risk of hospital admissions for MDs in Shanghai, China. Copyright © 2017 Elsevier B.V. All rights reserved.

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

EPA Science Inventory

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

Comparative evolution of oxygen, carbon dioxide, nitrogen, and sulfites during storage of a rosé wine bottled in PET and glass.

PubMed

Toussaint, Marie; Vidal, Jean-Claude; Salmon, Jean-Michel

2014-04-02

The management of dissolved and headspace gases during bottling and the choice of packaging are both key factors for the shelf life of wine. Two kinds of 75 cL polyethylene terephthalate (PET) bottles (with or without recycled PET) were compared to glass bottles filled with a rosé wine, closed with the same screwcaps and stored upright at 20 °C in light or in the dark. Analytical monitoring (aphrometric pressure, headspace volume, O2, N2, CO2, and SO2) was carried out for 372 days. After the consumption of O2 trapped during bottling, the total O2 content in glass bottles remained stable. A substantial decrease of CO2 and SO2 concentration and an increase of O2 concentration were observed in the PET bottles after 6 months because of the considerable gas permeability of monolayer PET. Light accelerated O2 consumption during the early months. Finally, the kinetic monitoring of partial pressures in gas and liquid phases in bottles showed contrasting behavior of O2 and N2 in comparison with CO2.

Oxidation of Gas-Phase SO2 on the Surfaces of Acidic Microdroplets: Implications for Sulfate and Sulfate Radical Anion Formation in the Atmospheric Liquid Phase.

PubMed

Hung, Hui-Ming; Hoffmann, Michael R

2015-12-01

The oxidation of SO2(g) on the interfacial layers of microdroplet surfaces was investigated using a spray-chamber reactor coupled to an electrospray ionization mass spectrometer. Four major ions, HSO3(-), SO3(•-), SO4(•-) and HSO4(-), were observed as the SO2(g)/N2(g) gas-mixture was passed through a suspended microdroplet flow, where the residence time in the dynamic reaction zone was limited to a few hundred microseconds. The relatively high signal intensities of SO3(•-), SO4(•-), and HSO4(-) compared to those of HSO3(-) as observed at pH < 3 without addition of oxidants other than oxygen suggests an efficient oxidation pathway via sulfite and sulfate radical anions on droplets possibly via the direct interfacial electron transfer from HSO3(-) to O2. The concentrations of HSO3(-) in the aqueous aerosol as a function of pH were controlled by the deprotonation of hydrated sulfur dioxide, SO2·H2O, which is also affected by the pH dependent uptake coefficient. When H2O2(g) was introduced into the spray chamber simultaneously with SO2(g), HSO3(-) is rapidly oxidized to form bisulfate in the pH range of 3 to 5. Conversion to sulfate was less at pH < 3 due to relatively low HSO3(-) concentration caused by the fast interfacial reactions. The rapid oxidation of SO2(g) on the acidic microdroplets was estimated as 1.5 × 10(6) [S(IV)] (M s(-1)) at pH ≤ 3. In the presence of acidic aerosols, this oxidation rate is approximately 2 orders of magnitude higher than the rate of oxidation with H2O2(g) at a typical atmospheric H2O2(g) concentration of 1 ppb. This finding highlights the relative importance of the acidic surfaces for SO2 oxidation in the atmosphere. Surface chemical reactions on aquated aerosol surfaces, as observed in this study, are overlooked in most atmospheric chemistry models. These reaction pathways may contribute to the rapid production of sulfate aerosols that is often observed in regions impacted by acidic haze aerosol such as Beijing and other megacities around the world.

Effect of heterogeneous aqueous reactions on the secondary formation of inorganic aerosols during haze events

DOE PAGES

Quan, Jiannong; Liu, Yangang; Liu, Quan; ...

2015-09-30

In this study, the effect of heterogeneous aqueous reactions on the secondary formation of inorganic aerosols during haze events was investigated by analysis of comprehensive measurements of aerosol composition and concentrations [e.g., particular matters (PM 2.5), nitrate (NO 3), sulfate (SO 4), ammonium (NH 4)], gas-phase precursors [e.g., nitrogen oxides (NOx), sulfur dioxide (SO 2), and ozone (O 3)], and relevant meteorological parameters [e.g., visibility and relative humidity (RH)]. The measurements were conducted in Beijing, China from Sep. 07, 2012 to Jan. 16, 2013. The results show that the conversion ratios of N from NOx to nitrate (N ratio) andmore » S from SO 2 to sulfate (S ratio) both significantly increased in haze events, suggesting enhanced conversions from NOx and SO 2 to their corresponding particle phases in the late haze period. Further analysis shows that N ratio and S ratio increased with increasing RH, with N ratio and S ratio being only 0.04 and 0.03, respectively, when RH < 40%, and increasing up to 0.16 and 0.12 when RH reached 60–80%, respectively. The enhanced conversion ratios of N and S in the late haze period is likely due to heterogeneous aqueous reactions, because solar radiation and thus the photochemical capacity are reduced by the increases in aerosols and RH. This point was further affirmed by the relationships of N ratio and S ratio to O 3: the conversion ratios increase with decreasing O 3 concentration when O 3 concentration is lower than <15 ppb but increased with increasing O 3 when O 3 concentration is higher than 15 ppb. The results suggest that heterogeneous aqueous reactions likely changed aerosols and their precursors during the haze events: in the beginning of haze events, the precursor gases accumulated quickly due to high emission and low reaction rate; the occurrence of heterogeneous aqueous reactions in the late haze period, together with the accumulated high concentrations of precursor gases such as SO 2 and NOx, accelerated the formation of secondary inorganic aerosols, and led to rapid increase of the PM 2.5 concentration.« less

Volcano related atmospheric toxicants in Hilo and Hawaii Volcanoes National Park: implications for human health.

PubMed

Michaud, Jon-Pierre; Krupitsky, Dmitry; Grove, John S; Anderson, Bruce S

2005-08-01

Volcanic fog (vog) from Kilauea volcano on the island of Hawaii includes a variety of chemical species including sulfur compounds and traces of metals such as mercury. The metal species seen tended to be in the nanograms per cubic meter range, whereas oxides of sulfur: SO2 and SO3 and sulfate aerosols, were in the range of micrograms per cubic meter and rarely even as high as a few milligrams per cubic meter of air (nominally ppb to ppm). These sulfur species are being investigated for associations with both acute and chronic changes in human health status. The sulfate aerosols tend to be less than 1 microm in diameter and tend to dominate the mass of this submicron size mode. The sulfur chemistry is dynamic, changing composition from predominantly sulfur dioxide and trioxide gasses near the volcano, to predominantly sulfate aerosols on the west side of the island. Time, concentration and composition characteristics of submicron aerosols and sulfur dioxide are described with respect to the related on-going health studies and public health management concerns. Exposures to sulfur dioxide and particulate matter equal to or less than 1 microm in size were almost always below the national ambient air quality standards (NAAQS). These standards do not however consider the acidic nature and submicron size of the aerosol, nor the possibility of the aerosol and the sulfur dioxide interacting in their toxicity. Time series plots, histograms and descriptive statistics of hourly averages give the reader a sense of some of the exposures observed.

Quantifying the impact of current and future concentrations of air pollutants on respiratory disease risk in England.

PubMed

Pannullo, Francesca; Lee, Duncan; Neal, Lucy; Dalvi, Mohit; Agnew, Paul; O'Connor, Fiona M; Mukhopadhyay, Sabyasachi; Sahu, Sujit; Sarran, Christophe

2017-03-27

Estimating the long-term health impact of air pollution in a spatio-temporal ecological study requires representative concentrations of air pollutants to be constructed for each geographical unit and time period. Averaging concentrations in space and time is commonly carried out, but little is known about how robust the estimated health effects are to different aggregation functions. A second under researched question is what impact air pollution is likely to have in the future. We conducted a study for England between 2007 and 2011, investigating the relationship between respiratory hospital admissions and different pollutants: nitrogen dioxide (NO 2 ); ozone (O 3 ); particulate matter, the latter including particles with an aerodynamic diameter less than 2.5 micrometers (PM 2.5 ), and less than 10 micrometers (PM 10 ); and sulphur dioxide (SO 2 ). Bayesian Poisson regression models accounting for localised spatio-temporal autocorrelation were used to estimate the relative risks (RRs) of pollution on disease risk, and for each pollutant four representative concentrations were constructed using combinations of spatial and temporal averages and maximums. The estimated RRs were then used to make projections of the numbers of likely respiratory hospital admissions in the 2050s attributable to air pollution, based on emission projections from a number of Representative Concentration Pathways (RCP). NO 2 exhibited the largest association with respiratory hospital admissions out of the pollutants considered, with estimated increased risks of between 0.9 and 1.6% for a one standard deviation increase in concentrations. In the future the projected numbers of respiratory hospital admissions attributable to NO 2 in the 2050s are lower than present day rates under 3 Representative Concentration Pathways (RCPs): 2.6, 6.0, and 8.5, which is due to projected reductions in future NO 2 emissions and concentrations. NO 2 concentrations exhibit consistent substantial present-day health effects regardless of how a representative concentration is constructed in space and time. Thus as concentrations are predicted to remain above limits set by European Union Legislation until the 2030s in parts of urban England, it will remain a substantial health risk for some time.

Impact of the 2008 Beijing Olympics on the risk of pregnancy complications.

PubMed

Assibey-Mensah, Vanessa; Liu, Kaibo; Thurston, Sally W; Stevens, Timothy P; Zhang, Junfeng; Zhang, Jinliang; Kane, Cathleen; Pan, Ying; Weinberger, Barry; Ohman-Strickland, Pamela; Woodruff, Tracey; Rich, David Q

2016-07-03

Taking advantage of the natural experiment of the 2008 Beijing Olympics (August 8 to September 24), when air pollution levels decreased by 13% to 60%, the authors assessed whether having ≥1 pregnancy month during the Olympics was associated with decreased risks of hypertensive disorders (HDs) and/or fetal-placental conditions (FPCs). Singleton births to mothers with ≥1 pregnancy month in 2008 or 2009 (N = 56,155) were included. Using generalized additive models, the authors estimated the risk of HDs and FPCs associated with (1) the 2008 Olympics compared with the same dates in 2009, and (2) increased mean ambient PM10 (particulate matter with an aerodynamic diameter <10 μm), NO2 (nitrogen dioxide), and SO2 (sulfur dioxide) concentrations during each trimester. However, no association between HDs or FPCs and having any trimester during the 2008 Olympic period was found. This may, in part, be due to a small number of pregnancy complications in this population.

LIGNOSULFONATE-MODIFIED CALCIUM HYDROXIDE FOR SULFUR DIOXIDE CONTROL

EPA Science Inventory

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

The impacts of air pollution on maternal stress during pregnancy

NASA Astrophysics Data System (ADS)

Lin, Yanfen; Zhou, Leilei; Xu, Jian; Luo, Zhongcheng; Kan, Haidong; Zhang, Jinsong; Yan, Chonghuai; Zhang, Jun

2017-01-01

To investigate the association of air pollution with maternal stress during pregnancy, we enrolled 1,931 women during mid-to-late pregnancy in Shanghai in 2010. The “Life-Event Scale for Pregnant Women” and “Symptom-Checklist-90-Revised Scale” (SCL-90-R) were used to evaluate life event stress and emotional stress, respectively. Air pollution data were collected for each district where pregnant women lived during pregnancy. We associated ambient air pollution with stress scores using multivariable logistic regression models. After adjusting for relevant covariates, an interquartile-range (IQR) increase in sulphur-dioxide (SO2) (OR = 1.30, 95% CI: 1.11-1.52) and particulate-matter with an aerodynamic-diameter <10 μm (PM10) (OR = 1.16, 95% CI: 1.02-1.34) concentrations on the recruitment day, and in the 5-day moving average concentrations of nitrogen-dioxide (NO2) (OR = 1.34, 95% CI: 1.05-1.70) were associated with high Global-Severity-Indices (P75-P100) of the SCL-90-R. These associations were stronger among women bearing high levels (P25-P100) of air pollutants than among women experiencing low levels (P1-P25) of pollutants. The stronger associations and higher levels of pollutants were observed in the cool season than in the warm season. SO2 increases on the recruitment day were also associated with an increased risk of high depression scores (P75-P100). Our findings supported a dose-dependent association between air pollution and emotional stress during pregnancy.

The impacts of air pollution on maternal stress during pregnancy

PubMed Central

Lin, Yanfen; Zhou, Leilei; Xu, Jian; Luo, Zhongcheng; Kan, Haidong; Zhang, Jinsong; Yan, Chonghuai; Zhang, Jun

2017-01-01

To investigate the association of air pollution with maternal stress during pregnancy, we enrolled 1,931 women during mid-to-late pregnancy in Shanghai in 2010. The “Life-Event Scale for Pregnant Women” and “Symptom-Checklist-90-Revised Scale” (SCL-90-R) were used to evaluate life event stress and emotional stress, respectively. Air pollution data were collected for each district where pregnant women lived during pregnancy. We associated ambient air pollution with stress scores using multivariable logistic regression models. After adjusting for relevant covariates, an interquartile-range (IQR) increase in sulphur-dioxide (SO2) (OR = 1.30, 95% CI: 1.11–1.52) and particulate-matter with an aerodynamic-diameter <10 μm (PM10) (OR = 1.16, 95% CI: 1.02–1.34) concentrations on the recruitment day, and in the 5-day moving average concentrations of nitrogen-dioxide (NO2) (OR = 1.34, 95% CI: 1.05–1.70) were associated with high Global-Severity-Indices (P75-P100) of the SCL-90-R. These associations were stronger among women bearing high levels (P25-P100) of air pollutants than among women experiencing low levels (P1-P25) of pollutants. The stronger associations and higher levels of pollutants were observed in the cool season than in the warm season. SO2 increases on the recruitment day were also associated with an increased risk of high depression scores (P75-P100). Our findings supported a dose-dependent association between air pollution and emotional stress during pregnancy. PMID:28098225

Outdoor Air Pollution and COPD-Related Emergency Department Visits, Hospital Admissions, and Mortality: A Meta-Analysis.

PubMed

DeVries, Rebecca; Kriebel, David; Sama, Susan

2017-02-01

A systematic literature review was performed to identify all peer-reviewed literature quantifying the association between short-term exposures of particulate matter <2.5 microns (PM 2.5 ), nitrogen dioxide (NO 2 ), and sulfur dioxide (SO 2 ) and COPD-related emergency department (ED) visits, hospital admissions (HA), and mortality. These results were then pooled for each pollutant through meta-analyses with a random effects model. Subgroup meta-analyses were explored to study the effects of selected lag/averaging times and health outcomes. A total of 37 studies satisfied our inclusion criteria, contributing to a total of approximately 1,115,000 COPD-related acute events (950,000 HAs, 80,000 EDs, and 130,000 deaths) to our meta-estimates. An increase in PM 2.5 of 10 ug/m 3 was associated with a 2.5% (95% CI: 1.6-3.4%) increased risk of COPD-related ED and HA, an increase of 10 ug/m 3 in NO 2 was associated with a 4.2% (2.5-6.0%) increase, and an increase of 10 ug/m 3 in SO 2 was associated with a 2.1% (0.7-3.5%) increase. The strength of these pooled effect estimates, however, varied depending on the selected lag/averaging time between exposure and outcome. Similar pooled effects were estimated for each pollutant and COPD-related mortality. These results suggest an ongoing threat to the health of COPD patients from both outdoor particulates and gaseous pollutants. Ambient outdoor concentrations of PM 2.5 , NO 2 , and SO 2 were significantly and positively associated with both COPD-related morbidity and mortality.

Volcanic sulfur dioxide and carbon dioxide measurements using small unmanned aerial systems

NASA Astrophysics Data System (ADS)

Pieri, D. C.; Diaz, J. A.; Fladeland, M. M.; Bland, G.; Alan, A., Jr.; Alegria, O.; Buongiorno, M. F.; Christensen, L. E.; Corrales, E.; Linick, J.; Mouginis-Mark, P. J.; Ramsey, M. S.; Realmuto, V. J.; Schwandner, F. M.

2015-12-01

Volcanoes emit gases continuously with significant pre-post-eruption changes, mainly H2O and CO2, plus SO2, and others. The SO2/CO2 ratio changes within volcanic life cycles making it an indicator of oncoming eruption phases: it can dip weeks to months before eruptions, then increase, and decrease back to background after eruptions. Over the last five years, we have made an effort to develop small and inexpensive lighter-than-air and fixed wing unmanned aerial vehicle (UAV) platforms in Costa Rica at Turrialba Volcano. Turrialba is an appropriate natural laboratory to test and prove platforms and instrumentation in low-level steady state volcanogenic gas and aerosol emissions at moderate altitudes (<12Kft ASL), where good technical infrastructure exists, with good physical access to the volcano. Our program in Costa Rica includes: (1) systematic monitoring of Turrialba from orbit with the Advanced Spaceborne Thermal Emission and Reflection radiometer (ASTER), with its thermal infrared (TIR) camera for SO2 retrieval, and more recently with GOSAT and OCO-2 for CO2; (2) in situ observations from aerostats and UAVs during ASTER overpasses, and (3) reconciliation of the orbital results with in situ data to validate mass retrieval and transport models. As part of the NASA HyspIRI Preparatory Airborne Activities program, we will conduct similar observations at Kilauea volcano using small UAVs and for both SO2 and CO2 in situ. One of the salient characteristics of the long lived Kilauea eruptions since 1983 has been the emission of SO2 in significant amounts, generating environmental stresses on local inhabitants due to lowered air quality, and stress on vegetation. Kilauea volcanic plumes, as with Turrialba, are mainly gases and liquid--SO2 is hydrolyzed to H2SO4 and the resulting highly acidic liquid aerosol is termed "vog," an environmental health hazard. Measurement of the diffuse CO2 emissions at Kilauea will also be of interest. Such measurements at Turrialba, indicate summit CO2 concentrations of up to 4000ppmv, and flank CO2 values of up to1500ppmv. We will discuss our SO2 and CO2 results at Turrialba and in Italy, and plans for Hawaii. Work presented here was done, in part, under contract to the NASA Earth Surface and Interior Focus Area, at the Jet Propulsion Laboratory of the California Institute of Technology.

Sulfur Dioxide Accelerates the Heterogeneous Oxidation Rate of Organic Aerosol by Hydroxyl Radicals

DOE PAGES

Richards-Henderson, Nicole K.; Goldstein, Allen H.; Wilson, Kevin R.

2016-03-08

There remains considerable uncertainty in how anthropogenic gas phase emissions alter the oxidative aging of organic aerosols in the troposphere. Here we observe a 10-20 fold acceleration in the effective heterogeneous OH oxidation rate of organic aerosol in the presence of SO 2. This acceleration originates from the radical chain reactions propagated by alkoxy radicals, which are formed efficiently inside the particle by the reaction of peroxy radicals with SO 2. As the OH approaches atmospheric concentrations, the radical chain length increases, transforming the aerosol at rates predicted to be up to 10 times the OH-aerosol collision frequency. Model predictions,more » constrained by experiments over orders of magnitude changes in [OH] and [SO 2], suggest that in polluted regions the heterogeneous processing of organic aerosols by OH ([SO 2] ≥ 40 ppb) occur on similar time scales as analogous gas-phase oxidation reactions. These results provide evidence for a previously unidentified mechanism by which organic aerosol oxidation is enhanced by anthropogenic gas phase emissions. (Chemical Equation Presented).« less

Ambient air pollution and preterm birth: A prospective birth cohort study in Wuhan, China.

PubMed

Qian, Zhengmin; Liang, Shengwen; Yang, Shaoping; Trevathan, Edwin; Huang, Zhen; Yang, Rong; Wang, Jing; Hu, Ke; Zhang, Yiming; Vaughn, Michael; Shen, Longjiao; Liu, Wenjin; Li, Pu; Ward, Patrick; Yang, Li; Zhang, Wei; Chen, Wei; Dong, Guanghui; Zheng, Tongzhang; Xu, Shunqing; Zhang, Bin

2016-03-01

Although studies in western countries suggest that ambient air pollution is positively associated with adverse pregnancy outcomes, the upper levels of pollutant exposures have been relatively low, thus eroding confidence in the conclusions. Meanwhile, in Asia, where upper levels of exposure have been greater, there have been limited studies of the association between air pollution and adverse pregnancy outcomes. The primary objective was to evaluate whether high levels of pollution, including particulate matter pollution with a mass median aerodynamic diameter of less than 2.5 μm (PM2.5) and 10 μm (PM10), sulfur dioxide (SO2), nitrogen dioxide (NO2), ozone (O3), and carbon monoxide (CO) are related to increased occurrence of preterm birth (PTB). We conducted a population-based study in Wuhan, China in a cohort of 95,911 live births during a two-year period from 2011 to 2013. The exposure was estimated based on daily mean concentrations of pollutants estimated using the pollutants' measurements from the nine closest monitors. Logistic regressions were performed to determine the relationships between exposure to each of the pollutants during different pregnancy periods and PTB while controlling for key covariates. We found 3% (OR=1.03; 95% CI: 1.02, 1.05), 2% (OR=1.02; 95% CI: 1.02, 1.03), 15% (OR=1.15; 95% CI: 1.11, 1.19), and 5% (OR=1.05; 95% CI: 1.02, 1.07) increases in risk of PTB with each 5-μg/m(3) increase in PM2.5 and PM10 concentrations, 100-μg/m(3) increase in CO concentrations, and 10-μg/m(3) increase in O3 concentrations, respectively. There was negligible evidence for associations for SO2 and NO2. The effects from two-pollutant models were similar to the estimated effects from single pollutant models. No critical exposure windows were identified consistently: the strongest effect for PTB was found in the second trimester for PM2.5, PM10, and CO, but for SO2 it was in the first trimester, second month, and third month. For NO2 it was in the first trimester and second month, and for O3, the third trimester. Findings reveal an association between air pollutants and PTB. However, more toxicological studies and prospective cohort studies with improved exposure assessments are needed to establish causality related to specific pollutants. Copyright © 2015 Elsevier GmbH. All rights reserved.

Ionic strength dependence of the oxidation of SO2 by H2O2 in sodium chloride particles

NASA Astrophysics Data System (ADS)

Ali, H. M.; Iedema, M.; Yu, X.-Y.; Cowin, J. P.

2014-06-01

The reaction of sulfur dioxide and hydrogen peroxide in the presence of deliquesced (>75% RH) sodium chloride (brine) particles was studied by utilizing a cross flow mini-reactor. The reaction kinetics were followed by observing chloride depletion in particles by computer-controlled scanning electron microscope with energy dispersive X-ray analysis, namely CCSEM/EDX. The reactions take place in concentrated mixed salt brine aerosols, for which no complete kinetic equilibrium data previously existed. We measured the Henry's law solubility of H2O2 in brine solutions to close that gap. We also calculated the reaction rate as the particle transforms continuously from concentrated NaCl brine to, eventually, a mixed NaHSO4 plus H2SO4 brine solution. The reaction rate of the SO2 oxidation by H2O2 was found to be influenced by the change in ionic strength as the particle undergoes compositional transformation, following closely the dependence of the third order rate constant on ionic strength as predicted using established rate equations. This is the first study that has measured the ionic strength dependence of sulfate formation (in non-aqueous media) from oxidation of mixed salt brine aerosols in the presence of H2O2. It also gives the first report of the dependence of the Henry's law constant of H2O2 on ionic strength.

Ionic strength dependence of the oxidation of SO2 by H2O2 in sodium chloride particles

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

Ali, Hashim M.; Iedema, Martin J.; Yu, Xiao-Ying

The reaction of sulfur dioxide and hydrogen peroxide in the presence of deliquesced (>75% RH) sodium particles was studied by utilizing a crossflow-mini reactor. The reaction kinetics was followed by observing chloride depletion in particles by computer-controlled scanning electron microscope with energy dispersive X-ray analysis, namely SEM/EDX. The reactions take place in concentrated mixed salt brine aerosols, for which no complete kinetic equilibrium data previously existed. We measured the Henry’s law solubility of H2O2 to close that gap. We also calculated the reaction rate as the particle transforms continuously from concentrated NaCl brine to eventually a mixed NaHSO4 plus H2SO4more » brine solution. The reaction rate of the SO2 oxidation by H2O2 was found to be influenced by the change in ionic strength as the particle undergoes compositional transformation, following closely the dependence of the third order rate constant on ionic strength as predicted rates using previously established rate equations. This is the first study that has measured the ionic strength dependence of sulfate formation (in non-aqueous media) from oxidation of mixed salt brine aerosols in the presence of H2O2. It also gives the first report of the Henry’s law constant of H2O2 dependence on ionic strength.« less

Theoretical studies of the marine sulfur cycle

NASA Technical Reports Server (NTRS)

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

1985-01-01

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

Estimating the atmospheric concentration of Criegee intermediates and their possible interference in a FAGE-LIF instrument

NASA Astrophysics Data System (ADS)

Novelli, Anna; Hens, Korbinian; Tatum Ernest, Cheryl; Martinez, Monica; Nölscher, Anke C.; Sinha, Vinayak; Paasonen, Pauli; Petäjä, Tuukka; Sipilä, Mikko; Elste, Thomas; Plass-Dülmer, Christian; Phillips, Gavin J.; Kubistin, Dagmar; Williams, Jonathan; Vereecken, Luc; Lelieveld, Jos; Harder, Hartwig

2017-06-01

We analysed the extensive dataset from the HUMPPA-COPEC 2010 and the HOPE 2012 field campaigns in the boreal forest and rural environments of Finland and Germany, respectively, and estimated the abundance of stabilised Criegee intermediates (SCIs) in the lower troposphere. Based on laboratory tests, we propose that the background OH signal observed in our IPI-LIF-FAGE instrument during the aforementioned campaigns is caused at least partially by SCIs. This hypothesis is based on observed correlations with temperature and with concentrations of unsaturated volatile organic compounds and ozone. Just like SCIs, the background OH concentration can be removed through the addition of sulfur dioxide. SCIs also add to the previously underestimated production rate of sulfuric acid. An average estimate of the SCI concentration of ˜ 5.0 × 104 molecules cm-3 (with an order of magnitude uncertainty) is calculated for the two environments. This implies a very low ambient concentration of SCIs, though, over the boreal forest, significant for the conversion of SO2 into H2SO4. The large uncertainties in these calculations, owing to the many unknowns in the chemistry of Criegee intermediates, emphasise the need to better understand these processes and their potential effect on the self-cleaning capacity of the atmosphere.

Results of airborne measurements in the plume near and far from the 2014 Bardarbunga-Holuhraun eruption.

NASA Astrophysics Data System (ADS)

Arnason, Gylfi; Eliasson, Jonas; Weber, Konradin; Boehlke, Christoph; Palsson, Thorgeir; Rognvaldsson, Olafur; Thorsteinsson, Throstur; Platt, Ulrich; Tirpitz, Lukas; Jones, Roderic L.; Smith, Paul D.

2015-04-01

The Volcanic Ash Research (VAR) group is focused on airborne measurement of ash contamination to support safe air travel. In relations to the recent eruption, the group measured ash and several gaseous species in the plume 10-300 km from the volcano. The eruption emitted ash turned out to be mostly in the fine aerosol range (much less than 10 micrometers in diameter). Our highest measured concentrations were lower than 1 mg/m3 indicating that commercial air traffic was not threatened (greater than 2 mg/m3) by the ash contamination. But we measured sulfur dioxide (SO2 ) up to 90 mg/m3, which presented a potentially dangerous pollution problem. However, airborne measurements indicate that the sulfur concentration decays (probably due to scavenging) as the plume is carried by the wind from the volcano, which limits the area of immediate danger to the public. Here we present size distribution for particulate matter collected during flights, near and far from the crater at various times. The particle data is then compared with simultaneously collected sulfur dioxide data and the rate of decay of is estimated. Sulfur and particle concentration variations with height in the far plume are presented. Some airborne measurements for H2S, NO, NO2 and CO2 will also be presented. This includes correlation matrices for simultaneous measurements of these gases and comparison to National Air Quality Standards and background values.

Comparison of SO2 and NO2 observations from OMI and OMPS from 2012 to 2016

NASA Astrophysics Data System (ADS)

Wang, Y.; Wang, J.; Xu, X.; Yang, K.

2017-12-01

Both Sulfur dioxide (SO2) and nitrogen dioxide (NO2) are precursors of PM2.5 which has significant impacts on human health. We compare observations from Ozone Monitoring Instrument (OMI) which has data gap due to row anomaly and Ozone Mapping Profiler Suite (OMPS) that is currently the only operational UV satellite sensor providing contiguous daily global coverage. In this study, we examine changes of SO2 and NO2 in several polluted regions and see both upward trends and downward trends in different areas but trends observed by the two sensors are consistent in general. Some of these upward and downward trends are associated with economic development and implementation of emission control policy. In addition, we analyzed probability distribution function of SO2 and NO2 from the two sensors and how row anomaly effect the intercomparison.

Developing Standards to Qualify a Fine Water Mist Fire Extinguisher for Human Spaceflight

NASA Technical Reports Server (NTRS)

Graf, John

2011-01-01

NASA is developing a Fine Water Mist Portable Fire Extinguisher for use on the International Space Station. The International Space Station presently uses two different types of fire extinguishers: a water foam extinguisher in the Russian Segment, and a carbon dioxide extinguisher in the US Segment and Columbus and Kibo pressurized elements. Changes in emergency breathing equipment make Fine Water Mist operationally preferable. Supplied oxygen breathing systems allow for safe discharge of a carbon dioxide fire extinguisher, without concerns of the crew inhaling unsafe levels of carbon dioxide. But the Portable Breathing Apparatus offers no more than 15 minutes of capability, and continued use of hose based supplied oxygen systems increases the oxygen content in a fire situation. NASA has developed a filtering respirator cartridge for use in a fire environment. It is qualified to provide up to 90 minutes of capability, and because it is a filtering respirator it does not add oxygen to the environment. The fire response respirator cartridge does not filter carbon dioxide, so a crew member discharging a CO2 fire extinguisher while wearing this filtering respirator would be at risk of inhaling unsafe levels of CO2. Fine Water Mist extinguishes a fire without creating a large volume of air with reduced oxygen and elevated CO2. Compared to the carbon dioxide based Portable Fire Extinguisher, the flight qualification of Fine Water Mist systems requires special care. Qualification of the CO2 based Portable Fire Extinguisher began with the assumption that any fire on ISS would be extinguished if the air in the fire environment reached a critical concentration of CO2. Qualification of a CO2 based system requires the developers to make assertions and assumptions about vehicle geometry and the ability of the extinguisher to deliver CO2 in different geometric configurations, but the developers did not need to make assertions or assumptions about the size of the fire, the temperature, or the heat generation rate. Fine Water Mist systems extinguish a fire predominantly by removing heat -- so qualification standards must evaluate geometry, but also temperature, heat transfer, and heat generation rate. This paper outlines and describes the methods used to develop standards used to qualify Fine Water Mist systems for a human spaceflight environment.

Long-term effects of elevated carbon dioxide concentration on sour orange wood specific gravity, modulus of elasticity, and microfibril angle

Treesearch

David Kretschmann; James Evans; Mike Wiemann; Bruce A. Kimball; Sherwood B. Idso

2007-01-01

The carbon dioxide (CO2) concentration of Earth’s atmosphere continues to rise. Plants in general are responsive to changing CO2 concentrations, which suggests changes in agricultural productivity in the United States and around the world. The ability of plants to absorb CO2 during photosynthesis and then store carbon in their structure or sequester it in the soil has...

Amino-Functionalized Luminescent Metal-Organic Framework Test Paper for Rapid and Selective Sensing of SO2 Gas and Its Derivatives by Luminescence Turn-On Effect.

PubMed

Wang, Meng; Guo, Lin; Cao, Dapeng

2018-03-06

Rapid and selective sensing of sulfur dioxide (SO 2 ) gas has attracted more and more attention because SO 2 not only causes environmental pollution but also severely affects the health of human beings. Here we report an amino-functionalized luminescent metal-organic framework (MOF) material (i.e., MOF-5-NH 2 ) and further investigate its sensing property for SO 2 gas and its derivatives as a luminescent probe. The results indicate that the MOF-5-NH 2 probe can selectively and sensitively sense SO 2 derivatives (i.e., SO 3 2- ) in real time by a luminescence turn-on effect with a lower detection limit of 0.168 ppm and a response time of less than 15 s. Importantly, the luminescence turn-on phenomenon can be observed by the naked eye. We also assembled MOF-5-NH 2 into a test paper to achieve the aim of portable detection, and the lower-limit concentration of the test paper for sensing SO 2 in real time was found to be about 0.05 ppm. Moreover, MOF-5-NH 2 also shows good anti-interference ability, strong luminescence stability, and reusability, which means that this material is an excellent sensing candidate. The amino functionalization may also provide a modification strategy to design luminescent sensors for other atmospheric pollutants.

40 CFR 74.23 - 1985 Allowable SO2 emissions rate.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 40 Protection of Environment 16 2010-07-01 2010-07-01 false 1985 Allowable SO2 emissions rate. 74... (CONTINUED) SULFUR DIOXIDE OPT-INS Allowance Calculations for Combustion Sources § 74.23 1985 Allowable SO2... data: (i) Allowable SO2 emissions rate of the combustion source expressed in lbs/mmBtu as defined under...

The relationship between changes in daily air pollution and hospitalizations in Perth, Australia 1992-1998: a case-crossover study.

PubMed

Hinwood, A L; De Klerk, N; Rodriguez, C; Jacoby, P; Runnion, T; Rye, P; Landau, L; Murray, F; Feldwick, M; Spickett, J

2006-02-01

A case-crossover study was undertaken to investigate the relationship between daily air pollutant concentrations and daily hospitalizations for selected disease categories in Perth, Western Australia. Daily measurements of particles (measured by nephelometry and PM2.5), photochemical oxidants (measured as ozone), nitrogen dioxide (NO2) and carbon monoxide (CO) concentrations were obtained from 1992 to 1998 via a metropolitan network of monitoring stations. Daily PM2.5 concentrations were estimated using monitored data, modelling and interpolation. Hospital morbidity data for respiratory, cardiovascular (CVD), gastrointestinal (GI) diseases, chronic obstructive pulmonary diseases (COPD) excluding asthma; pneumonia/influenza diseases; and asthma were obtained and categorized into all ages, less than 15 years and greater than 65 years. Gastrointestinal morbidity was used as a control disease. The data were analyzed using conditional logistic regression. The results showed a small number of significant associations for daily changes in particle concentrations, nitrogen dioxide and carbon monoxide for the respiratory diseases, CODP, pneumonia, asthma and CVD hospitalizations. Changes in ozone concentrations were not significantly associated with any disease outcomes. These data provide useful information on the potential health impacts of air pollution in an airshed with very low sulphur dioxide concentrations and lower nitrogen dioxide concentrations commonly found in many other cities.

The impact of sulfur dioxide on plant sexual reproduction: in vivo and in vitro effects compared

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

DuBay, D.T.; Murdy, W.H.

1983-01-01

In Lepidium virginicum L., exposure of pollen to 0.6 ppm sulfur dioxide (SO/sub 2/) for 4 h reduced pollen germination in vitro 94% from the control, whereas exposure to 0.6 ppm SO/sub 2/ for 2, 4, and 8 h during flowering reduced pollen germination in vivo 50% from the control, but did not affect seed set.An interaction between SO/sub 2/ and water may have caused the inhibition of pollen germination in a liquid culture medium, as well as on the moist surface of an intact stigma. However, the results suggest that the use of pollen germination and pollen tube elongationmore » in vitro to asses the direct effects of SO/sub 2/ on plant sexual reproduction in vivo is not valid.« less

Impact of sulfur dioxide on plant sexual reproduction: in vivo and in vitro effects compared

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

Du Bay, D.T.; Murdy, W.H.

In Lepidium virginicum L., exposure of pollen to 0.6 ppm sulfur dioxide (SO/sub 2/) for 4 h reduced pollen germination in vitro 94% from the control, whereas exposure to 0.6 ppm SO/sub 2/ for 2, 4, and 8 h during flowering reduced pollen germination in vivo 50% from the control, but did not affect seed set. An interaction between SO/sub 2/ and water may have caused the inhibition of pollen germination in a liquid culture medium, as well as on the moist surface of an intact stigma. However, the results suggest that the use of pollen germination and pollen tubemore » elongation in vitro to assess the direct effects of SO/sub 2/ on plant secual reproduction in vivo is not valid.« less

40 CFR 60.642 - Standards for sulfur dioxide.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 40 Protection of Environment 7 2013-07-01 2013-07-01 false Standards for sulfur dioxide. 60.642... After January 20, 1984, and on or Before August 23, 2011 § 60.642 Standards for sulfur dioxide. (a... minimum, an SO2 emission reduction efficiency (Zi) to be determined from table 1 based on the sulfur feed...

40 CFR 49.129 - Rule for limiting emissions of sulfur dioxide.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 40 Protection of Environment 1 2013-07-01 2013-07-01 false Rule for limiting emissions of sulfur... emissions of sulfur dioxide. (a) What is the purpose of this section? This section limits the amount of sulfur dioxide (SO2) that may be emitted from certain air pollution sources operating within the Indian...

40 CFR 60.642 - Standards for sulfur dioxide.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 40 Protection of Environment 7 2014-07-01 2014-07-01 false Standards for sulfur dioxide. 60.642... After January 20, 1984, and on or Before August 23, 2011 § 60.642 Standards for sulfur dioxide. (a... minimum, an SO2 emission reduction efficiency (Zi) to be determined from table 1 based on the sulfur feed...

Comparative analyses of physiological responses of Cynodon dactylon accessions from Southwest China to sulfur dioxide toxicity.

PubMed

Li, Xi; Wang, Ling; Li, Yiqiao; Sun, Lingxia; Cai, Shizhen; Huang, Zhuo

2014-01-01

Sulfur dioxide (SO2), a major air pollutant in developing countries, is highly toxic to plants. To achieve better air quality and landscape, planting appropriate grass species in severe SO2 polluted areas is very critical. Cynodon dactylon, a widely used warm season turfgrass species, has good SO2-tolerant ability. In this study, we selected 9 out of 38 C. dactylon accessions from Southwest China as representatives of high, intermediate SO2-tolerant and SO2-sensitive accessions to comparatively analyze their physiological differences in leaves under SO2 untreated and treated conditions. Our results revealed that SO2-tolerant C. dactylon accessions showed higher soluble sugar, proline, and chlorophyll a contents under both SO2 treated and untreated conditions; higher chlorophyll b and carotenoid under SO2 treated condition; lower reactive oxygen species (ROS) level, oxidative damages, and superoxide dismutase (SOD) activities under SO2 treated condition; and higher peroxidase (POD) activities under SO2 untreated condition. Further results indicated that SO2-tolerant C. dactylon accessions had higher sulfur contents under both SO2 treated and untreated conditions, consistent with higher SO activities under both SO2 treated and untreated conditions, and higher SiR activities under SO2 treated condition. Taken together, our results indicated that SO2 tolerance of C. dactylon might be largely related to soluble sugar, proline and chlorophyll a contents, and SO enzyme activity.

Comparative Analyses of Physiological Responses of Cynodon dactylon Accessions from Southwest China to Sulfur Dioxide Toxicity

PubMed Central

Wang, Ling; Li, Yiqiao; Cai, Shizhen

2014-01-01

Sulfur dioxide (SO2), a major air pollutant in developing countries, is highly toxic to plants. To achieve better air quality and landscape, planting appropriate grass species in severe SO2 polluted areas is very critical. Cynodon dactylon, a widely used warm season turfgrass species, has good SO2-tolerant ability. In this study, we selected 9 out of 38 C. dactylon accessions from Southwest China as representatives of high, intermediate SO2-tolerant and SO2-sensitive accessions to comparatively analyze their physiological differences in leaves under SO2 untreated and treated conditions. Our results revealed that SO2-tolerant C. dactylon accessions showed higher soluble sugar, proline, and chlorophyll a contents under both SO2 treated and untreated conditions; higher chlorophyll b and carotenoid under SO2 treated condition; lower reactive oxygen species (ROS) level, oxidative damages, and superoxide dismutase (SOD) activities under SO2 treated condition; and higher peroxidase (POD) activities under SO2 untreated condition. Further results indicated that SO2-tolerant C. dactylon accessions had higher sulfur contents under both SO2 treated and untreated conditions, consistent with higher SO activities under both SO2 treated and untreated conditions, and higher SiR activities under SO2 treated condition. Taken together, our results indicated that SO2 tolerance of C. dactylon might be largely related to soluble sugar, proline and chlorophyll a contents, and SO enzyme activity. PMID:25097893

Precipitated Silica from Pumice and Carbon Dioxide Gas (Co2) in Bubble Column Reactor

NASA Astrophysics Data System (ADS)

Dewati, R.; Suprihatin, S.; Sumada, K.; Muljani, S.; Familya, M.; Ariani, S.

2018-01-01

Precipitated silica from silica and carbon dioxide gas has been studied successfully. The source of silica was obtained from pumice stone while precipitation process was carried out with carbon dioxide gas (CO2). The sodium silicate solution was obtained by extracting the silica from pumice stone with sodium hydroxide (NaOH) solution and heated to 100 °C for 1 h. The carbon dioxide gas is injected into the aqueous solution of sodium silicate in a bubble column reactor to form precipitated silica. m2/g. The results indicate that the products obtained are precipitate silica have surface area in the range of 100 - 227 m2/g, silica concentration more than 80%, white in appearance, and silica concentration reached 90% at pH 7.

Method of determining pH by the alkaline absorption of carbon dioxide

DOEpatents

Hobbs, D.T.

1992-10-06

A method is described for measuring the concentration of hydroxides in alkaline solutions in a remote location using the tendency of hydroxides to absorb carbon dioxide. The method includes the passing of carbon dioxide over the surface of an alkaline solution in a remote tank before and after measurements of the carbon dioxide solution. A comparison of the measurements yields the absorption fraction from which the hydroxide concentration can be calculated using a correlation of hydroxide or pH to absorption fraction. 2 figs.

Emission rates of sulfur dioxide and carbon dioxide from Redoubt Volcano, Alaska during the 1989-1990 eruptions

USGS Publications Warehouse

Casadevall, T.J.; Doukas, M.P.; Neal, C.A.; McGimsey, R.G.; Gardner, C.A.

1994-01-01

Airborne measurements of sulfur dioxide emission rates in the gas plume emitted from fumaroles in the summit crater of Redoubt Volcano were started on March 20, 1990 using the COSPEC method. During the latter half of the period of intermittent dome growth and destruction, between March 20 and mid-June 1990, sulfur dioxide emission rates ranged from approximately 1250 to 5850 t/d, rates notably higher than for other convergent-plate boundary volcanoes during periods of active dome growth. Emission rates following the end of dome growth from late June 1990 through May 1991 decreased steadily to less than 75 t/d. The largest mass of sulfur dioxide was released during the period of explosive vent clearing when explosive degassing on December 14-15 injected at least 175,000 ?? 50,000 tonnes of SO2 into the atmosphere. Following the explosive eruptions of December 1989, Redoubt Volcano entered a period of intermittent dome growth from late December 1989 to mid-June 1990 during which Redoubt emitted a total mass of SO2 ranging from 572,000 ?? 90,000 tonnes to 680,000 ?? 90,000 tonnes. From mid-June 1990 through May 1991, the volcano was in a state of posteruption degassing into the troposphere, producing approximately 183,000 ?? 50,000 tonnes of SO2. We estimate that Redoubt Volcano released a minimum mass of sulfur dioxide of approximately 930,000 tonnes. While COSPEC data were not obtained frequently enough to enable their use in eruption prediction, SO2 emission rates clearly indicated a consistent decline in emission rates between March through October 1990 and a continued low level of emission rates through the first half of 1991. Values from consecutive daily measurements of sulfur dioxide emission rates spanning the March 23, 1990 eruption decreased in the three days prior to eruption. That decrease was coincident with a several-fold increase in the frequency of shallow seismic events, suggesting partial sealing of the magma conduit to gas loss that resulted in pressurization of the shallow magma system and an increase in earthquake activity. Unlike the short-term SO2 decrease in March 1990, the long-term decrease of sulfur dioxide emission rates from March 1990 through May 1991 was coincident with low rates of seismic energy release and was interpreted to reflect gradual depressurization of the shallow magma reservoir. The long-term declines in seismic energy release and in SO2 emission rates led AVO scientists to conclude on April 19, 1991 that the potential for further eruptive activity from Redoubt Volcano had diminished, and on this basis, the level of concern color code for the volcano was changed from code yellow (Volcano is restless; earthquake activity is elevated; activity may include extrusion of lava) to code green (Volcano is in its normal 'dormant' state). ?? 1994.

Sap flux in pure aspen and mixed aspen-birch forests exposed to elevated concentrations of carbon dioxide and ozone

Treesearch

Johan Uddling; Ronald M. Teclaw; Mark E. Kubiske; Kurt S. Pregitzer; David S. Ellsworth

2008-01-01

Elevated concentrations of atmospheric carbon dioxide ([CO2]) and tropospheric ozone ([O3]) have the potential to affect tree physiology and structure and hence forest water use, which has implications for climate feedbacks. We investigated how a 40% increase above ambient values in [CO2] and [O

Theoretical and modeling studies of the atmospheric chemistry of sulfur oxide and hydroxyl radical systems

NASA Astrophysics Data System (ADS)

El-Zanan, Hazem S.

Models are the tools that integrate our understanding of the atmospheric processes. Box models are utilized frequently and used to simulate the fates and transformation of atmospheric pollutants. The results from models are usually used to produce one integrated system and further help the policy makers to develop control strategies. We have investigated the atmospheric chemistry of the SOx and HOx systems. The results of 15 laboratory experiments that involved the studies of the HO-SO2, reaction have been analyzed. Mixtures of HONO, NO, NO2, H2O, SO2 and CO were photolyzed in synthetic air or in nitrogen containing approximately 50 ppm oxygen. Upon analyzing the data we have found that a very large amount of the observed SO2 oxidation (70.0 +/- 9.1%) can not be explained through the gas phase reaction of HO + SO2 reaction alone. The Regional Atmospheric Chemistry Mechanism, Version 2 (RACM2) was used to investigate additional chemical pathways for the oxidation of SO2. The results indicate that a mechanism(s) involving photochemical heterogeneous reactions could account for the observed additional sulfur dioxide oxidation not accounted for by gas phase oxidation alone. We have also investigated the distribution of the hydroxyl radical in different urban and rural areas. Photolysis of ozone and its reactions with nitrogen oxides and organic compounds, including both anthropogenic and biogenic volatile organic compounds (VOCs), control the mixing ratios of the hydroxyl radical (HO). Measurements of ozone, nitrogen oxides and volatile hydrocarbons from a deciduous forest in July 1999 and six sites located in the San Joaquin Valley obtained during the Central California Ozone Study (CCOS) measured in July 2000 and September 2000 were used to estimate the hydroxyl radical concentrations. Two methods were employed to determine the concentrations: (1) box model simulations and (2) steady state approximation of the species concentrations (Production-Loss Method). The results indicate that the concentrations observed here in this study are comparable with the HO concentrations measured and/or modeled from other studies. HO concentrations produced from ozone, formaldehyde and isoprene were by far the most important sources for HO production but the HO removal processes greatly differs between the urban and rural areas. Hydroxyl radical concentrations vary by location, time of the day, season and meteorological conditions. Comparing the HO concentrations from our study with other studies from different urban, rural and marine environments shows that hydroxyl radical concentrations in the urban areas can be lower than some pristine environments.

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

NASA Technical Reports Server (NTRS)

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

1988-01-01

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

ASSESSMENT OF CROP LOSS FROM OZONE

EPA Science Inventory

Past research has shown that ozone (O3) alone or in combination with sulfur dioxide (SO2), and nitrogen dioxide (NO2) is responsible for up to 90% of the crop losses in the U.S. caused by air pollution. The National Crop Loss Assessment Network (NCLAN) was set up to determine mor...

Massive Volcanic SO2 Oxidation and Sulphate Aerosol Deposition in Cenozoic North America

EPA Science Inventory

Volcanic eruptions release a large amount of sulphur dioxide (SO₂) into the atmosphere. SO₂ is oxidized to sulphate and can subsequently form sulphate aerosol, which can affect the Earth's radiation balance, biologic productivity and high-altitude ozone co...

Reducing power production costs by utilizing petroleum coke. Annual report

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

Galbreath, K.C.

1998-07-01

A Powder River Basin subbituminous coal from the North Antelope mine and a petroleum shot coke were received from Northern States Power Company (NSP) for testing the effects of parent fuel properties on coal-coke blend grindability and evaluating the utility of petroleum coke blending as a strategy for improving electrostatic precipitator (ESP) particulate collection efficiency. Petroleum cokes are generally harder than coals, as indicated by Hardgrove grindability tests. Therefore, the weaker coal component may concentrate in the finer size fractions during the pulverizing of coal-coke blends. The possibility of a coal-coke size fractionation effect is being investigated because it maymore » adversely affect combustion performance, it may enhance ESP particulate collection efficiency. Petroleum cokes contain much higher concentrations of V relative to coals. Consequently, coke blending can significantly increase the V content of fly ash resulting from coal-coke combustion. Pentavalent vanadium oxide (V{sub 2}O{sub 5}) is a known catalyst for transforming gaseous sulfur dioxide (SO{sub 2}[g]) to gaseous sulfur trioxide (SO{sub 3}[g]). The presence of SO{sub 3}(g) strongly affects fly ash resistivity and, thus, ESP performance.« less

REDUCING POWER PRODUCTION COSTS BY UTILIZING PETROLEUM COKE

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

NONE

1998-09-01

A Powder River Basin subbituminous coal from the North Antelope mine and a petroleum shot coke were received from Northern States Power Company (NSP) for testing the effects of parent fuel properties on coal-coke blend grindability and evaluating the utility of petroleum coke blending as a strategy for improving electrostatic precipitator (ESP) particulate collection efficiency. Petroleum cokes are generally harder than coals, as indicated by Hardgrove grindability tests. Therefore, the weaker coal component may concentrate in the finer size fractions during the pulverizing of coal-coke blends. The possibility of a coal-coke size fractionation effect is being investigated because it maymore » adversely affect combustion performance. Although the blending of petroleum coke with coal may adversely affect combustion performance, it may enhance ESP particulate collection efficiency. Petroleum cokes contain much higher concentrations of V relative to coals. Consequently, coke blending can significantly increase the V content of fly ash resulting from coal-coke combustion. Pentavalent vanadium oxide (V{sub 2}O{sub 5}) is a known catalyst for transforming gaseous sulfur dioxide (SO{sub 2}[g]) to gaseous sulfur trioxide (SO{sub 3}[g]). The presence of SO{sub 3}(g) strongly affects fly ash resistivity and, thus, ESP performance.« less

Comparison of multiple methods for the determination of sulphite in Allium and Brassica vegetables

PubMed Central

Robbins Carlos, Katherine S.; de Jager, Lowri S.

2018-01-01

Sulphites are a family of additives regulated for use worldwide in food products. They must be declared on the label if they are present in concentrations greater than 10 mg kg−1, determined as sulphur dioxide (SO2). The current US regulatory method for sulphites, the optimised Monier–Williams method (OMW), produces false-positive results with vegetables from the Allium (garlic) and Brassica (cabbage) genera due to extraction conditions that are thought to cause endogenous sulphur compounds to release SO2. Recently, modifications to the OMW method (2× MW) were published that reportedly reduced this false-positive in garlic. However, no other vegetables from these genera have been investigated. In addition, an LC-MS/MS method was developed for sulphite analysis, but it has not yet been tested with these problematic matrices. Ten vegetable species were analysed using these sulphite methods (OMW titration, OMW gravimetric, 2× MW and LC-MS/MS) to determine the false-positive rate. Sulphite concentrations > 10 mg kg−1 SO2 were observed with the OMW analyses. The 2× MW method reduced the measured concentration in unsulphited samples to ≤ 10 mg kg−1 SO2 for all matrices analysed. The LC-MS/MS method showed concentrations < 10 mg kg−1 for the Brassica samples, but only displayed a slight reduction in the Allium matrices. Spiked recovery studies were conducted to determine if these methods can detect added sulphite. The 2× MW had recoveries of 17% and 42% for water and fresh garlic, respectively, and the LC-MS/MS had recoveries of 108%, 125%, 116% and 107% for water, fresh garlic, roasted garlic, and hummus, respectively. The low recoveries of the 2× MW may indicate that sulphur compounds cannot be properly quantified with this method. The ability to eliminate false-positives will enable accurate determination of added sulphite to ensure compliance with sulphite labelling requirements. PMID:27592824

Carbon dioxide elimination and regeneration of resources in a microwave plasma torch.

PubMed

Uhm, Han S; Kwak, Hyoung S; Hong, Yong C

2016-04-01

Carbon dioxide gas as a working gas produces a stable plasma-torch by making use of 2.45 GHz microwaves. The temperature of the torch flame is measured by making use of optical spectroscopy and a thermocouple device. Two distinctive regions are exhibited, a bright, whitish region of a high-temperature zone and a bluish, dimmer region of a relatively low-temperature zone. The bright, whitish region is a typical torch based on plasma species where an analytical investigation indicates dissociation of a substantial fraction of carbon dioxide molecules, forming carbon monoxides and oxygen atoms. The emission profiles of the oxygen atoms and the carbon monoxide molecules confirm the theoretical predictions of carbon dioxide disintegration in the torch. Various hydrocarbon materials may be introduced into the carbon dioxide torch, regenerating new resources and reducing carbon dioxide concentration in the torch. As an example, coal powders in the carbon dioxide torch are converted into carbon monoxide according to the reaction of CO2 + C → 2CO, reducing a substantial amount of carbon dioxide concentration in the torch. In this regards, the microwave plasma torch may be one of the best ways of converting the carbon dioxides into useful new materials. Copyright © 2015 Elsevier Ltd. All rights reserved.

EFFECTS OF FLY ASH TRANSITION METAL CONTENT AND FLUE GAS HCL/SO2 RATIO ON MERCURY SPECIATION IN WASTE COMBUSTION

EPA Science Inventory

The paper presents results of research on the effect of sulfur dioxide (SO2):HCI ratio on heterogeneous Hg0 oxidation. The addition of SO2 to moist flue gas at high SO2:HCI ratios (4:1 to 10:1) caused a decrease in oxidation of Hg0 relative to flur gas without SO2. This is attrib...

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

PubMed

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.

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

PubMed Central

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. PMID:25922579

40 CFR 63.1573 - What are my monitoring alternatives?

Code of Federal Regulations, 2014 CFR

2014-07-01

... operate a continuous gas analyzer to measure and record the concentration of carbon dioxide, carbon... control room instrumentations, dscm/min (dscf/min); %CO2 = Carbon dioxide concentration in regenerator... catalytic regenerator atmospheric exhaust gas flow rate for your catalytic reforming unit during the coke...

40 CFR 63.1573 - What are my monitoring alternatives?

Code of Federal Regulations, 2012 CFR

2012-07-01

... operate a continuous gas analyzer to measure and record the concentration of carbon dioxide, carbon... control room instrumentations, dscm/min (dscf/min); %CO2 = Carbon dioxide concentration in regenerator... catalytic regenerator atmospheric exhaust gas flow rate for your catalytic reforming unit during the coke...

Raman Spectra and Cross Sections of Ammonia, Chlorine, Hydrogen Sulfide, Phosgene, and Sulfur Dioxide Toxic Gases in the Fingerprint Region 400-1400 cm-1

DTIC Science & Technology

2016-02-11

AIP ADVANCES 6, 025310 (2016) Raman spectra and cross sections of ammonia , chlorine, hydrogen sulfide, phosgene, and sulfur dioxide toxic gases in...Received 10 December 2015; accepted 3 February 2016; published online 11 February 2016) Raman spectra of ammonia (NH3), chlorine (Cl2), hydrogen...and cross sections of ammonia (NH3), chlorine (Cl2), hydrogen sulfide (H2S), phosgene (CCl2O), and sulfur dioxide (SO2) toxic gases in the fingerprint

Simultaneous Measurements of CO2 Concentration and Temperature profiles using 1.6 μm DIAL in the Lower-Atmosphere

NASA Astrophysics Data System (ADS)

Shibata, Y.; Nagasawa, C.; Abo, M.

2016-12-01

High-accurate vertical carbon dioxide (CO2) profiles are highly desirable in the inverse method to improve quantification and understanding of the global sink and source of CO2, and also global climate change. We have developed a ground based 1.6μm differential absorption lidar (DIAL) to achieve measurements of vertical CO2 profiles in the atmosphere. As the spectra of absorption lines of any molecules are influenced basically by the temperature and pressure in the atmosphere, it is important to measure them simultaneously so that the better accuracy of the DIAL measurement is realized. The barometric formula can derive atmospheric pressure of each altitude using atmospheric pressure of ground level at the lidar site. Comparison of atmospheric pressure prlofiles calculated from this equation and those obtained from radiosonde observations at Tateno, Japan are consisted within 0.2 % below 3 km altitude. So, we have developed a 1.6 μm CO2 DIAL system for simultaneous measurements of the CO2 concentration and temperature profiles in the lower-atmosphere. Laser beams of three wavelengths around a CO2 absorption spectrum is transmitted alternately to the atmosphere. Moreover, the value of the retrieved CO2 concentration will be improved remarkably by processing the iteration assignment of CO2 concentration and temperature, which measured by these DIAL techniques. We have acheived vertical CO2 concentration and temperature profile from 0.5 to 2.0 km altitude by this DIAL system. In the next step, we will use this high accuracy CO2 concentration profile and back-trajectory analysis for the behavior analysis of the CO2 mass. This work was financially supported by the System Development Program for Advanced Measurement and Analysis of the Japan Science and Technology Agency.

Chlorine dioxide reactions with indoor materials during building disinfection: surface uptake.

PubMed

Hubbard, Heidi; Poppendieck, Dustin; Corsi, Richard L

2009-03-01

Chlorine dioxide received attention as a building disinfectant in the wake of Bacillus anthracis contamination of several large buildings in the fall of 2001. It is increasingly used for the disinfection of homes and other indoor environments afflicted by mold. However, little is known regarding the interaction of chlorine dioxide and indoor materials, particularly as related to the removal of chlorine dioxide from air. Such removal may be undesirable with respect to the subsequent formation of localized zones of depleted disinfectant concentrations and potential reductions in disinfection effectiveness in a building. The focus of this paper is on chlorine dioxide removal from air to each of 24 different indoor materials. Experiments were completed with materials housed in flow-through 48-L stainless steel chambers under standard conditions of 700 ppm chlorine dioxide inlet concentration, 75% relative humidity, 24 degrees C, and 0.5 h(-1) air changes. Chlorine dioxide concentration profiles, deposition velocities, and reaction probabilities are described in this paper. Deposition velocities and reaction probabilities varied over approximately 2 orders of magnitude across all materials. For most materials, deposition velocity decreased significantly over a 16-h disinfection period; that is, materials became smaller sinks for chlorine dioxide with time. Four materials (office partition, ceiling tile, medium density fiberboard, and gypsum wallboard) accounted for the most short- and long-term consumption of chlorine dioxide. Deposition velocity was observed to be a strong function of chlorine dioxide inlet concentration, suggesting the potential importance of chemical reactions on or within test materials.

Table of Historical Sulfur Dioxide National Ambient Air Quality Standards (NAAQS)

EPA Pesticide Factsheets

See the history of limits to the level of sulfur dioxide (SO2) in ambient air, set through the NAAQS review and rulemaking process under the Clean Air Act. This includes both primary and secondary standards.

Manipulating the Surface Chemistry of Quantum Dots for Sensitive Ratiometric Fluorescence Detection of Sulfur Dioxide.

PubMed

Li, Huihui; Zhu, Houjuan; Sun, Mingtai; Yan, Yehan; Zhang, Kui; Huang, Dejian; Wang, Suhua

2015-08-11

Herein, we report a novel approach to the rapid visual detection of gaseous sulfur dioxide (SO2) by manipulating the surface chemistry of 3-aminopropyltriethoxysilane (APTS)-modified quantum dots (QDs) using fluorescent coumarin-3-carboxylic acid (CCA) for specific reaction with SO2. The CCA molecules are attached to the surface amino groups of the QDs through electrostatic attraction, thus the fluorescence of CCA is greatly suppressed because of the formation of an ion-pair complex between the ATPS-modified QDs and CCA. Such an interaction is vulnerable to SO2 because SO2 can readily react with surface amino groups to form strong charge-transfer complexes and subsequently release the strongly fluorescent CCA molecules. The mechanism has been carefully verified through a series of control experiments. Upon exposure to different amounts of SO2, the fluorescent color of the nanoparticle-based sensor displays continuously changes from red to blue. Most importantly, the approach owns high selectivity for SO2 and a tolerance of interference, which enables the sensor to detect SO2 in a practical application. Using this fluorescence-based sensing method, we have achieved a visual detection limit of 6 ppb for gaseous SO2.

Inter-seasonal and spatial distribution of ground-level greenhouse gases (CO2, CH4, N2O) over Nagpur in India and their management roadmap.

PubMed

Majumdar, Deepanjan; Rao, Padma; Maske, Nilam

2017-03-01

Ground-level concentrations of carbon dioxide (CO 2 ), methane (CH 4 ), and nitrous oxide (N 2 O) were monitored over three seasons, i.e., post-monsoon (September-October), winter (January-February), and summer (May-June) for 1 year during 2013-2014 in Nagpur City in India. The selected gases had moderate to high variation both spatially (residential, commercial, traffic intersections, residential cum commercial sites) and temporally (at 7:00, 13:00, 18:00, and 23:00 hours in all three seasons). Concentrations of gases were randomly distributed diurnally over city in all seasons, and there was no specific increasing or decreasing trend with time in a day. Average CO 2 and N 2 O concentrations in winter were higher over post-monsoon and summer while CH 4 had highest average concentration in summer. Observed concentrations of CO 2 were predominantly above global average of 400 ppmv while N 2 O and CH 4 concentrations frequently dropped down below global average of 327 ppbv and 1.8 ppmv, respectively. Two-tailed Student's t test indicated that post-monsoon CO 2 concentrations were statistically different from summer but not so from winter, while difference between summer and winter concentrations was statistically significant (P < 0.05). CH 4 concentrations in all seasons were statistically at par to each other. In case of N 2 O, concentrations in post-monsoon were statistically different from summer but not so from winter, while difference between summer and winter concentrations was statistically significant (P < 0.05). Average ground-level concentrations of the gases calculated for three seasons together were higher in commercial areas. Environmental management priorities vis a vis greenhouse gas emissions in the city are also discussed.

40 CFR 96.203 - Measurements, abbreviations, and acronyms.

Code of Federal Regulations, 2010 CFR

2010-07-01

... PROGRAMS (CONTINUED) NOX BUDGET TRADING PROGRAM AND CAIR NOX AND SO2 TRADING PROGRAMS FOR STATE IMPLEMENTATION PLANS CAIR SO2 Trading Program General Provisions § 96.203 Measurements, abbreviations, and...—nitrogen oxides O2—oxygen ppm—parts per million scfh—standard cubic feet per hour SO2—sulfur dioxide yr...

Tethered catalysts for the hydration of carbon dioxide

DOEpatents

Valdez, Carlos A; Satcher, Jr., Joe H; Aines, Roger D; Wong, Sergio E; Baker, Sarah E; Lightstone, Felice C; Stolaroff, Joshuah K

2014-11-04

A system is provided that substantially increases the efficiency of CO.sub.2 capture and removal by positioning a catalyst within an optimal distance from the air-liquid interface. The catalyst is positioned within the layer determined to be the highest concentration of carbon dioxide. A hydrophobic tether is attached to the catalyst and the hydrophobic tether modulates the position of the catalyst within the liquid layer containing the highest concentration of carbon dioxide.

Statistical persistence of air pollutants (O3,SO2,NO2 and PM10) in Mexico City

NASA Astrophysics Data System (ADS)

Meraz, M.; Rodriguez, E.; Femat, R.; Echeverria, J. C.; Alvarez-Ramirez, J.

2015-06-01

The rescaled range (R / S) analysis was used for analyzing the statistical persistence of air pollutants in Mexico City. The air-pollution time series consisted of hourly observations of ozone, nitrogen dioxide, sulfur dioxide and particulate matter obtained at the Mexico City downtown monitoring station during 1999-2014. The results showed that long-range persistence is not a uniform property over a wide range of time scales, from days to months. In fact, although the air pollutant concentrations exhibit an average persistent behavior, environmental (e.g., daily and yearly) and socio-economic (e.g., daily and weekly) cycles are reflected in the dependence of the persistence strength as quantified in terms of the Hurst exponent. It was also found that the Hurst exponent exhibits time variations, with the ozone and nitrate oxide concentrations presenting some regularity, such as annual cycles. The persistence dynamics of the pollutant concentrations increased during the rainy season and decreased during the dry season. The time and scale dependences of the persistence properties provide some insights in the mechanisms involved in the internal dynamics of the Mexico City atmosphere for accumulating and dissipating dangerous air pollutants. While in the short-term individual pollutants dynamics seems to be governed by specific mechanisms, in the long-term (for monthly and higher scales) meteorological and seasonal mechanisms involved in atmospheric recirculation seem to dominate the dynamics of all air pollutant concentrations.

40 CFR 63.1573 - What are my monitoring alternatives?

Code of Federal Regulations, 2013 CFR

2013-07-01

... continuous gas analyzer to measure and record the concentration of carbon dioxide, carbon monoxide, and... instrumentations, dscm/min (dscf/min); %CO2 = Carbon dioxide concentration in regenerator exhaust, percent by... regenerator atmospheric exhaust gas flow rate for your catalytic reforming unit during the coke burn and...

MERCURY SPECIATION IN COMBUSTION SYSTEMS: STUDIES WITH SIMULATED FLUE GASES AND MODEL FLY ASHES

EPA Science Inventory

The paper gives results of a bench-scale study of the effects of flue gas and fly ash parameters on the oxidation of elemental mercury in simulated flue gases containing hydrogen chloride (HCl), nitric oxide (NO), nitrogen dioxide (NO2), sulfur dioxide (SO2), and water vapor (H2O...

Development of a distributed air pollutant dry deposition modeling framework.

PubMed

Hirabayashi, Satoshi; Kroll, Charles N; Nowak, David J

2012-12-01

A distributed air pollutant dry deposition modeling system was developed with a geographic information system (GIS) to enhance the functionality of i-Tree Eco (i-Tree, 2011). With the developed system, temperature, leaf area index (LAI) and air pollutant concentration in a spatially distributed form can be estimated, and based on these and other input variables, dry deposition of carbon monoxide (CO), nitrogen dioxide (NO(2)), sulfur dioxide (SO(2)), and particulate matter less than 10 microns (PM10) to trees can be spatially quantified. Employing nationally available road network, traffic volume, air pollutant emission/measurement and meteorological data, the developed system provides a framework for the U.S. city managers to identify spatial patterns of urban forest and locate potential areas for future urban forest planting and protection to improve air quality. To exhibit the usability of the framework, a case study was performed for July and August of 2005 in Baltimore, MD. Copyright © 2012 Elsevier Ltd. All rights reserved.

Photocatalytic surface reactions on indoor wall paint.

PubMed

Salthammer, T; Fuhrmann, F

2007-09-15

The reduction of indoor air pollutants by air cleaning systems has received considerable interest, and a number of techniques are now available. So far, the method of photocatalysis was mainly applied by use of titanium dioxide (TiO2) in flow reactors under UV light of high intensity. Nowadays, indoor wall paints are equipped with modified TiO2 to work as a catalyst under indoor daylight or artificial light. In chamber experiments carried out under indoor related conditions itwas shown thatthe method works for nitrogen dioxide with air exchange and for formaldehyde without air exchange at high concentrations. In further experiments with volatile organic compounds (VOCs), a small effect was found for terpenoids with high kOH rate constants. For other VOCs and carbon monoxide there was no degradation at all or the surface acted as a reversible sink. Secondary emissions from the reaction of paint constituents were observed on exposure to light. From the results it is concluded that recipes of photocatalytic wall paints need to be optimized for better efficiency under indoor conditions.

Determination of priority among air pollution factors in preventing COPD in residents of Shanghai City proper

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

Xuguang, Tao; Chuan-jie, Hong; Shun-zhang, Yu

The purpose of our study is to determine the priority among ambient sulphur dioxide (SO{sub 2}), inhalable particulates (IP), and indoor use of coal for cooking or heating to prevent COPD in residents of Shanghai city proper. We describe spatial and temporal distribution of the concentration of ambient SO{sub 2}, IP, and the proportion of families who use coal (1980-1985) by the trend surface simulating method and other statistics. Stratified by two sets of extreme levels of ambient SO{sub 2}, IP, and the proportion of coal-using families, we selected eight groups with different combinations of exposure levels. We analyzed themore » relationship between air pollution factors and their health effects at levels of mortality (1978-1987, 232,459 person years), prevalence (1987, 12,037 persons), lung function and local immunologic function (1987, 514 women) with logistic and stepwise regression, and ridit analysis. After controlling for possible confounders, e.g., tobacco smoking and occupational exposure, we found that indoor use of coal is a more important risk factor than ambient SO{sub 2} and IP. We then used canonical correlation analysis to evaluate the overall exposure-effect relationship between one set of air pollution and confounding factors and the other set of health effect indices. High correlation is found between the two. The indoor use of coal is more important for the overall health effects than the ambient SO{sub 2} and IP, to change from coal to gas could reduce the environmental exposure canonical variable more readily, with an effect equivalent to a reduction of 0.1839 mg/m{sup 3} for ambient SO{sub 2}, or 0.2806 mg/m{sup 3} for ambient IP in concentration.« less

Assessment of indoor air quality in office buildings across Europe - The OFFICAIR study.

PubMed

Mandin, Corinne; Trantallidi, Marilena; Cattaneo, Andrea; Canha, Nuno; Mihucz, Victor G; Szigeti, Tamás; Mabilia, Rosanna; Perreca, Erica; Spinazzè, Andrea; Fossati, Serena; De Kluizenaar, Yvonne; Cornelissen, Eric; Sakellaris, Ioannis; Saraga, Dikaia; Hänninen, Otto; De Oliveira Fernandes, Eduardo; Ventura, Gabriela; Wolkoff, Peder; Carrer, Paolo; Bartzis, John

2017-02-01

The European project OFFICAIR aimed to broaden the existing knowledge regarding indoor air quality (IAQ) in modern office buildings, i.e., recently built or refurbished buildings. Thirty-seven office buildings participated in the summer campaign (2012), and thirty-five participated in the winter campaign (2012-2013). Four rooms were investigated per building. The target pollutants were twelve volatile organic compounds, seven aldehydes, ozone, nitrogen dioxide and particulate matter with aerodynamic diameter <2.5μm (PM 2.5 ). Compared to other studies in office buildings, the benzene, toluene, ethylbenzene, and xylene concentrations were lower in OFFICAIR buildings, while the α-pinene and d-limonene concentrations were higher, and the aldehyde, nitrogen dioxide and PM 2.5 concentrations were of the same order of magnitude. When comparing summer and winter, significantly higher concentrations were measured in summer for formaldehyde and ozone, and in winter for benzene, α-pinene, d-limonene, and nitrogen dioxide. The terpene and 2-ethylhexanol concentrations showed heterogeneity within buildings regardless of the season. Considering the average of the summer and winter concentrations, the acetaldehyde and hexanal concentrations tended to increase by 4-5% on average with every floor level increase, and the nitrogen dioxide concentration tended to decrease by 3% on average with every floor level increase. A preliminary evaluation of IAQ in terms of potential irritative and respiratory health effects was performed. The 5-day median and maximum indoor air concentrations of formaldehyde and ozone did not exceed their respective WHO air quality guidelines, and those of acrolein, α-pinene, and d-limonene were lower than their estimated thresholds for irritative and respiratory effects. PM 2.5 indoor concentrations were higher than the 24-h and annual WHO ambient air quality guidelines. Copyright © 2016 Elsevier B.V. All rights reserved.

Ambient Air Pollution and Daily Outpatient Visits for Cardiac Arrhythmia in Shanghai, China

PubMed Central

Zhao, Ang; Chen, Renjie; Kuang, Xingya; Kan, Haidong

2014-01-01

Background Cardiac arrhythmias are cardiac rhythm disorders that comprise an important public health problem. Few prior studies have examined the association between ambient air pollution and arrhythmias in general populations in mainland China. Methods We performed a time-series analysis to investigate the short-term association between air pollution (particulate matter with an aerodynamic diameter less than 10 µm [PM10], sulfur dioxide [SO2], and nitrogen dioxide [NO2]) and outpatient visits for arrhythmia in Shanghai, China. We applied the over-dispersed Poisson generalized additive model to analyze the associations after control for seasonality, day of the week, and weather conditions. We then stratified the analyses by age, gender, and season. Results We identified a total of 56 940 outpatient visits for cardiac arrhythmia. A 10-µg/m3 increase in the present-day concentrations of PM10, SO2, and NO2 corresponded to increases of 0.56% (95% CI 0.42%, 0.70%), 2.07% (95% CI 1.49%, 2.64%), and 2.90% (95% CI 2.53%, 3.27%), respectively, in outpatient arrhythmia visits. The associations were stronger in older people (aged ≥65 years) and in females. This study provides the first evidence that ambient air pollution is significantly associated with increased risk of cardiac arrhythmia in mainland China. Conclusions Our analyses provide evidence that the current air pollution levels have an adverse effect on cardiovascular health and strengthened the rationale for further limiting air pollution levels in the city. PMID:24835409

Effects of switching to lower sulfur marine fuel oil on air quality in the San Francisco Bay area.

PubMed

Tao, Ling; Fairley, David; Kleeman, Michael J; Harley, Robert A

2013-09-17

Ocean-going vessels burning high-sulfur heavy fuel oil are an important source of air pollutants, such as sulfur dioxide and particulate matter. Beginning in July 2009, an emission control area was put into effect at ports and along the California coastline, requiring use of lower sulfur fuels in place of heavy fuel oil in main engines of ships. To assess impacts of the fuel changes on air quality at the Port of Oakland and in the surrounding San Francisco Bay area, we analyzed speciated fine particle concentration data from four urban sites and two more remote sites. Measured changes in concentrations of vanadium, a specific marker for heavy fuel oil combustion, are related to overall changes in aerosol emissions from ships. We found a substantial reduction in vanadium concentrations after the fuel change and a 28-72% decrease in SO2 concentrations, with the SO2 decrease varying depending on proximity to shipping lanes. We estimate that the changes in ship fuel reduced ambient PM2.5 mass concentrations at urban sites in the Bay area by about 3.1 ± 0.6% or 0.28 ± 0.05 μg/m(3). The largest contributing factor to lower PM mass concentrations was reductions in particulate sulfate. Absolute sulfate reductions were fairly consistent across sites, whereas trace metal reductions were largest at a monitoring site in West Oakland near the port.

Incidence of asthma among workers exposed to sulphur dioxide and other irritant gases.

PubMed

Andersson, E; Knutsson, A; Hagberg, S; Nilsson, T; Karlsson, B; Alfredsson, L; Torén, K

2006-04-01

The aim of the present study was to investigate whether repeated peak exposure (gassings) to sulphur dioxide (SO2) and other irritant gases increases the risk of new-onset asthma. A questionnaire was sent to 4,112 sulphite workers, of whom 1,919 completed the questionnaire and 396 completed the short-form questionnaire, which was sent out as a last reminder. A sample of 130 nonrespondents completed a telephone interview using the short-form questionnaire. The incidence of adult-onset, physician-diagnosed asthma during employment duration was analysed in relation to exposure to SO2 and gassings giving rise to respiratory symptoms. Incidence rates, as well as incidence rate ratios with 95% confidence interval (CI), were calculated. Further Cox regression models were used allowing assessment of hazard ratios (HR) stratified for sex and adjusted for atopy, smoking habits and age. The incidence rate for asthma among sulphite mill workers reporting gassings of SO2 was 6.2 out of 1,000 person-yrs, compared with 1.9 out of 1,000 person-yrs among subjects unexposed to SO2 and any gassings (HR (95% CI) 4.0 (2.1-7.7)). Among males reporting gassings to SO2, the HR (95% CI) for asthma was 5.8 (2.6-13) compared with unexposed males. In conclusion, repeated peak exposure to sulphur dioxide increased the incidence of asthma during work in sulphite pulp mills, which supports the hypothesis of irritant-induced asthma.

Evaluating the effect of sample type on American alligator ( Alligator mississippiensis) analyte values in a point-of-care blood analyser

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

Hamilton, Matthew T.; Finger, John W.; Winzeler, Megan E.

The assessment of wildlife health has been enhanced by the ability of point-of-care (POC) blood analysers to provide biochemical analyses of non-domesticated animals in the field. However, environmental limitations (e.g. temperature, atmospheric humidity and rain) and lack of reference values may inhibit researchers from using such a device with certain wildlife species. Evaluating the use of alternative sample types, such as plasma, in a POC device may afford researchers the opportunity to delay sample analysis and the ability to use banked samples. In this study, we examined fresh whole blood, fresh plasma and frozen plasma (sample type) pH, partial pressuremore » of carbon dioxide (PCO 2), bicarbonate (HCO 3₋), total carbon dioxide (TCO 2), base excess (BE), partial pressure of oxygen (PO 2), oxygen saturation (sO 2) and lactate concentrations in 23 juvenile American alligators (Alligator mississippiensis) using an i-STAT CG4+ cartridge. Our results indicate that sample type had no effect on lactate concentration values (F 2,65 = 0.37, P = 0.963), suggesting that the i-STAT analyser can be used reliably to quantify lactate concentrations in fresh and frozen plasma samples. In contrast, the other seven blood parameters measured by the CG4+ cartridge were significantly affected by sample type. In conclusion, we were able to collect blood samples from all alligators within 2 min of capture to establish preliminary reference ranges for juvenile alligators based on values obtained using fresh whole blood.« less

Evaluating the effect of sample type on American alligator (Alligator mississippiensis) analyte values in a point-of-care blood analyser

PubMed Central

Hamilton, Matthew T.; Finger, John W.; Winzeler, Megan E.; Tuberville, Tracey D.

2016-01-01

The assessment of wildlife health has been enhanced by the ability of point-of-care (POC) blood analysers to provide biochemical analyses of non-domesticated animals in the field. However, environmental limitations (e.g. temperature, atmospheric humidity and rain) and lack of reference values may inhibit researchers from using such a device with certain wildlife species. Evaluating the use of alternative sample types, such as plasma, in a POC device may afford researchers the opportunity to delay sample analysis and the ability to use banked samples. In this study, we examined fresh whole blood, fresh plasma and frozen plasma (sample type) pH, partial pressure of carbon dioxide (PCO2), bicarbonate (HCO3−), total carbon dioxide (TCO2), base excess (BE), partial pressure of oxygen (PO2), oxygen saturation (sO2) and lactate concentrations in 23 juvenile American alligators (Alligator mississippiensis) using an i-STAT CG4+ cartridge. Our results indicate that sample type had no effect on lactate concentration values (F2,65 = 0.37, P = 0.963), suggesting that the i-STAT analyser can be used reliably to quantify lactate concentrations in fresh and frozen plasma samples. In contrast, the other seven blood parameters measured by the CG4+ cartridge were significantly affected by sample type. Lastly, we were able to collect blood samples from all alligators within 2 min of capture to establish preliminary reference ranges for juvenile alligators based on values obtained using fresh whole blood. PMID:27382469

Evaluating the effect of sample type on American alligator ( Alligator mississippiensis) analyte values in a point-of-care blood analyser

DOE PAGES

Hamilton, Matthew T.; Finger, John W.; Winzeler, Megan E.; ...

2016-01-01

The assessment of wildlife health has been enhanced by the ability of point-of-care (POC) blood analysers to provide biochemical analyses of non-domesticated animals in the field. However, environmental limitations (e.g. temperature, atmospheric humidity and rain) and lack of reference values may inhibit researchers from using such a device with certain wildlife species. Evaluating the use of alternative sample types, such as plasma, in a POC device may afford researchers the opportunity to delay sample analysis and the ability to use banked samples. In this study, we examined fresh whole blood, fresh plasma and frozen plasma (sample type) pH, partial pressuremore » of carbon dioxide (PCO 2), bicarbonate (HCO 3₋), total carbon dioxide (TCO 2), base excess (BE), partial pressure of oxygen (PO 2), oxygen saturation (sO 2) and lactate concentrations in 23 juvenile American alligators (Alligator mississippiensis) using an i-STAT CG4+ cartridge. Our results indicate that sample type had no effect on lactate concentration values (F 2,65 = 0.37, P = 0.963), suggesting that the i-STAT analyser can be used reliably to quantify lactate concentrations in fresh and frozen plasma samples. In contrast, the other seven blood parameters measured by the CG4+ cartridge were significantly affected by sample type. In conclusion, we were able to collect blood samples from all alligators within 2 min of capture to establish preliminary reference ranges for juvenile alligators based on values obtained using fresh whole blood.« less

Sodium fluoride and sulfur dioxide affected male reproduction by disturbing blood-testis barrier in mice.

PubMed

Zhang, Jianhai; Li, Zhihui; Qie, Mingli; Zheng, Ruibo; Shetty, Jagathpala; Wang, Jundong

2016-08-01

Fluoride and sulfur dioxide (SO2), two well-known environmental toxicants, have been implicated to have adverse effects on male reproductive health in humans and animals. The objective of this study to investigate if the BTB is one of the pathways that lead to reproductive toxicity of sodium fluoride and sulfur dioxide alone or in combination, in view of the key role of blood testis barrier (BTB) in testis. The results showed that a marked decrease in sperm quality, and altered morphology and ultrastructure of BTB in testis of mice exposure to fluoride (100 mg NaF/L in drinking water) or/and sulfur dioxide (28 mg SO2/m(3), 3 h/day). Meanwhile, the mRNA expression levels of some vital BTB-associated proteins, including occluding, claudin-11, ZO-1, Ncadherin, α-catenin, and connexin-43 were all strikingly reduced after NaF exposure, although only the reduction of DSG-2 was statistically significant in all treatment groups. Moreover, the proteins expressions also decreased significantly in claudin-11, N-cadherin, α-catenin, connexin-43 and desmoglein-2 in mice treated with fluoride and/or SO2. These changes in BTB structure and constitutive proteins may therefore be connected with the low sperm quality in these mice. The role of fluoride should deserves more attention in this process. Copyright © 2016 Elsevier Ltd. All rights reserved.

Ship-based MAX-DOAS measurements of tropospheric NO2, SO2, and HCHO distribution along the Yangtze River

NASA Astrophysics Data System (ADS)

Hong, Qianqian; Liu, Cheng; Chan, Ka Lok; Hu, Qihou; Xie, Zhouqing; Liu, Haoran; Si, Fuqi; Liu, Jianguo

2018-04-01

In this paper, we present ship-based Multi-Axis Differential Optical Absorption Spectroscopy (MAX-DOAS) measurements of tropospheric trace gases' distribution along the Yangtze River during winter 2015. The measurements were performed along the Yangtze River between Shanghai and Wuhan, covering major industrial areas in eastern China. Tropospheric vertical column densities (VCDs) of nitrogen dioxide (NO2), sulfur dioxide (SO2), and formaldehyde (HCHO) were retrieved using the air mass factor calculated by the radiative transfer model. Enhanced tropospheric NO2 and SO2 VCDs were detected over downwind areas of industrial zones over the Yangtze River. In addition, spatial distributions of atmospheric pollutants are strongly affected by meteorological conditions; i.e., positive correlations were found between concentration of pollutants and wind speed over these areas, indicating strong influence of transportation of pollutants from high-emission upwind areas along the Yangtze River. Comparison of tropospheric NO2 VCDs between ship-based MAX-DOAS and Ozone Monitoring Instrument (OMI) satellite observations shows good agreement with each other, with a Pearson correlation coefficient (R) of 0.82. In this study, the NO2 / SO2 ratio was used to estimate the relative contributions of industrial sources and vehicle emissions to ambient NO2 levels. Analysis results of the NO2 / SO2 ratio show a higher contribution of industrial NO2 emissions in Jiangsu Province, while NO2 levels in Jiangxi and Hubei provinces are mainly related to vehicle emissions. These results indicate that different pollution control strategies should be applied in different provinces. In addition, multiple linear regression analysis of ambient carbon monoxide (CO) and odd oxygen (Ox) indicated that the primary emission and secondary formation of HCHO contribute 54.4 ± 3.7 % and 39.3 ± 4.3 % to the ambient HCHO, respectively. The largest contribution from primary emissions in winter suggested that photochemically induced secondary formation of HCHO is reduced due to lower solar irradiance in winter. Our findings provide an improved understanding of major pollution sources along the eastern part of the Yangtze River which are useful for designing specific air pollution control policies.

Electrochemical sensing of sulphur dioxide: a comparison using dodecanethiol and citrate capped gold nanoclusters.

PubMed

Sathe, Bhaskar R; Risbud, Mandar S; Mulla, Imtiaz S; Pillai, Vijayamohanan K

2008-06-01

A comparison of cyclic voltammograms of dodecanethiol (DDT) capped Au nanoclusters (5.0 0.5 nm) and trisodium citrate (Cit) capped Au nanoclusters (approximately 10-15 nm) modified glassy carbon electrode shows a dramatic variation in the current when exposed to a small amount of sulphur dioxide. This is explained using the electrocatalytic properties of Au nanoclusters towards the oxidation of SO2, thus facilitating the fabrication of electrochemical sensors for the detection of SO2. The intrinsic redox changes observed for gold nanocluster-modified glassy carbon electrodes disappear on passing SO2, despite a dramatic current increase, which indeed scales up with the amount of dissolved SO2. Interestingly, a complete rejuvenation of the redox behavior of gold is also observed on subsequent removal of SO2 from the solution by passing pure nitrogen for 15 minutes. Further, these nanoclusters when characterized with X-ray photoelectron spectroscopy (XPS) and Fourier transform infrared spectroscopy (FTIR) after SO2 passage reveal a variety of SO2 adsorption modes on gold surface. XP spectra also show a shift of 1.03 eV towards higher binding energy indicating a strong adsorption of SO2 gas, while FTIR gives conclusive evidence for the interaction of SO2 with gold nanoparticles.

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

NASA Technical Reports Server (NTRS)

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.

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

NASA Technical Reports Server (NTRS)

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 5days. 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.

Analysis of Emission Reduction Strategies for Power Boilers in the US Pulp and Paper Industry.

EPA Science Inventory

The U.S. pulp and paper industry utilizes a variety of fuels to provide energy for process needs. Energy production results in air emissions of sulfur dioxide (SO2), nitrogen oxides (NOX), particulate matter (PM), and greenhouse gases such as carbon dioxide (CO2). Air emissions f...

Analysis of Strategies for Reducing Multiple Emissions from Electric Power Plants: SO2, Nox, CO2

EIA Publications

2001-01-01

This report responds to a request received from Senator David McIntosh on June 29, 2000 to analyze the impacts on energy consumers and producers of coordinated strategies to reduce emissions of sulfur dioxide, nitrogen oxides, and carbon dioxide at U.S. power plants.

Evaluation of a Colorimetric Personal Dosimeter for Nitrogen Oxide.

ERIC Educational Resources Information Center

Diamond, Philip

A personal colorimetric dosimeter for nitrogen dioxide was developed. Tests were performed to determine the response of these strips to various concentrations of NO2. The dosimeter strips were satisfactory for approximate determinations of total exposure (concentration + time) of nitrogen dioxide. The total exposure was calculated in terms of time…

30 CFR 75.388 - Boreholes in advance of mining.

Code of Federal Regulations, 2013 CFR

2013-07-01

... more than 1.0 percent methane, less than 19.5 percent oxygen, or harmful concentrations of carbon monoxide, carbon dioxide or other explosive, harmful or noxious gases; (2) Tests for methane, oxygen... and the mine workings; (3) The concentrations of methane, oxygen, carbon monoxide, and carbon dioxide...

30 CFR 75.388 - Boreholes in advance of mining.

Code of Federal Regulations, 2010 CFR

2010-07-01

... more than 1.0 percent methane, less than 19.5 percent oxygen, or harmful concentrations of carbon monoxide, carbon dioxide or other explosive, harmful or noxious gases; (2) Tests for methane, oxygen... and the mine workings; (3) The concentrations of methane, oxygen, carbon monoxide, and carbon dioxide...

30 CFR 75.388 - Boreholes in advance of mining.

Code of Federal Regulations, 2012 CFR

2012-07-01

... more than 1.0 percent methane, less than 19.5 percent oxygen, or harmful concentrations of carbon monoxide, carbon dioxide or other explosive, harmful or noxious gases; (2) Tests for methane, oxygen... and the mine workings; (3) The concentrations of methane, oxygen, carbon monoxide, and carbon dioxide...

30 CFR 75.388 - Boreholes in advance of mining.

Code of Federal Regulations, 2014 CFR

2014-07-01

... more than 1.0 percent methane, less than 19.5 percent oxygen, or harmful concentrations of carbon monoxide, carbon dioxide or other explosive, harmful or noxious gases; (2) Tests for methane, oxygen... and the mine workings; (3) The concentrations of methane, oxygen, carbon monoxide, and carbon dioxide...

30 CFR 75.388 - Boreholes in advance of mining.

Code of Federal Regulations, 2011 CFR

2011-07-01

... more than 1.0 percent methane, less than 19.5 percent oxygen, or harmful concentrations of carbon monoxide, carbon dioxide or other explosive, harmful or noxious gases; (2) Tests for methane, oxygen... and the mine workings; (3) The concentrations of methane, oxygen, carbon monoxide, and carbon dioxide...

Elevated atmospheric carbon dioxide concentration affects interactions between Spodoptera exigua (Lepidoptera: Noctuidae) larvae and two host plant species outdoors

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

Caulfield, F.; Bunce, J.A.

1994-08-01

Beet armyworm, Spodoptera exigua (Huebner), larvae were placed on sugarbeet (Beta vulgaris L.) and pigweed (Amaranthus hybridus L.) plants in outdoor chambers in which the plants were growing at either the ambient ([approximately] 350 [mu]l liter[sup [minus]1]) or ambient plus 350 [mu]l liter[sup [minus]1] ([approximately] 700 [mu]l liter[sup [minus]1]) carbon dioxide concentration. A series of experiments was performed to determine if larvae reduced plant growth differently at the two carbon dioxide concentrations in either species and if the insect growth or survival differed with carbon dioxide concentration. Leaf nitrogen, water, starch, and soluble carbohydrate contents were measured to assess carbonmore » dioxide concentration effects on leaf quality. Insect feeding significantly reduced plant growth in sugarbeet plants at 350 [mu]l liter[sup [minus]1] but not at 700 [mu]l liter[sup [minus]1] nor in pigweed at either carbon dioxide concentration. Larval survival was greater on sugarbeet plants at the elevated carbon dioxide concentration. Increased survival occurred only if the insects were at the elevated carbon dioxide concentration and consumed leaf material grown at the elevated concentration. Leaf quality was only marginally affected by growth at elevated carbon dioxide concentration in these experiments. The results indicate that in designing experiments to predict effects of elevated atmospheric carbon dioxide concentrations on plant-insect interactions, both plants and insects should be exposed to the experimental carbon dioxide concentrations, as well as to as realistic environmental conditions as possible.« less

Role of Endogenous Sulfur Dioxide in Regulating Vascular Structural Remodeling in Hypertension

PubMed Central

Chen, Selena; Tang, Chaoshu

2016-01-01

Sulfur dioxide (SO2), an emerging gasotransmitter, was discovered to be endogenously generated in the cardiovascular system. Recently, the physiological effects of endogenous SO2 were confirmed. Vascular structural remodeling (VSR), an important pathological change in many cardiovascular diseases, plays a crucial role in the pathogenesis of the diseases. Here, the authors reviewed the research progress of endogenous SO2 in regulating VSR by searching the relevant data from PubMed and Medline. In spontaneously hypertensive rats (SHRs) and pulmonary hypertensive rats, SO2/aspartate aminotransferase (AAT) pathway was significantly altered. SO2 inhibited vascular smooth muscle cell (VSMC) proliferation, promoted apoptosis, inhibited the synthesis of extracellular collagen but promoted its degradation, and enhanced antioxidative capacity, thereby playing a significant role in attenuating VSR. However, the detailed mechanisms needed to be further explored. Further studies in this field would be important for the better understanding of the pathogenesis of systemic hypertension and pulmonary hypertension. Also, clinical trials are needed to demonstrate if SO2 would be a potential therapeutic target in cardiovascular diseases. PMID:27721913

Attribution of atmospheric sulfur dioxide over the English Channel to dimethyl sulfide and changing ship emissions

NASA Astrophysics Data System (ADS)

Yang, Mingxi; Bell, Thomas G.; Hopkins, Frances E.; Smyth, Timothy J.

2016-04-01

Atmospheric sulfur dioxide (SO2) was measured continuously from the Penlee Point Atmospheric Observatory (PPAO) near Plymouth, United Kingdom, between May 2014 and November 2015. This coastal site is exposed to marine air across a wide wind sector. The predominant southwesterly winds carry relatively clean background Atlantic air. In contrast, air from the southeast is heavily influenced by exhaust plumes from ships in the English Channel as well as near Plymouth Sound. A new International Maritime Organization (IMO) regulation came into force in January 2015 to reduce the maximum allowed sulfur content in ships' fuel 10-fold in sulfur emission control areas such as the English Channel. Our observations suggest a 3-fold reduction in ship-emitted SO2 from 2014 to 2015. Apparent fuel sulfur content calculated from coincidental SO2 and carbon dioxide (CO2) peaks from local ship plumes show a high level of compliance to the IMO regulation (> 95 %) in both years (˜ 70 % of ships in 2014 were already emitting at levels below the 2015 cap). Dimethyl sulfide (DMS) is an important source of atmospheric SO2 even in this semi-polluted region. The relative contribution of DMS oxidation to the SO2 burden over the English Channel increased from about one-third in 2014 to about one-half in 2015 due to the reduction in ship sulfur emissions. Our diel analysis suggests that SO2 is removed from the marine atmospheric boundary layer in about half a day, with dry deposition to the ocean accounting for a quarter of the total loss.

Regulatory Impact Analysis (RIA) for the Proposed Revisions to the Sulfur Dioxide National Ambient Air Quality Standards (NAAQS)

EPA Pesticide Factsheets

This Regulatory Impact Analysis (RIA) provides estimates of the incremental costs and monetized human health benefits of attaining a revised short‐term Sulfur Dioxide (SO2) NAAQS within the current monitoring network.

Fact Sheets and Additional Information Regarding the Primary National Ambient Air Quality Standard (NAAQS) for Sulfur Dioxide

EPA Pesticide Factsheets

Find tools for primary standards for Sulfur Dioxide, maps of nonattainment areas, an overview of the proposal, projected nonattainment areas for 2020, and a presentation on the 2011 SO2 primary NAAQS revision.

SOXAL combined SO{sub x}/NO{sub x} flue gas control demonstration. Quarterly report, January--March 1993

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

NONE

AQUATECH Systems a business unit of Allied-Signal Inc., proposes to demonstrate the technical viability and cost effectiveness of the SOXAL process a combined SO{sub x}/NO{sub x} control process on a 3 MW equivalent flue gas slip stream from Niagara Mohawk Power Corporation, Dunkirk Steam Station Boiler No. 4, a coal fired boiler. The SOXAL process combines 90+% sulfur dioxide removal from the flue gas using a sodium based scrubbing solution and regeneration of the spent scrubbing liquor using AQUATECH Systems` proprietary bipolar membrane technology. This regeneration step recovers a stream of sulfur dioxide suitable for subsequent processing to salable sulfurmore » or sulfuric acid. Additionally 90+% control of NO{sub x} gases can be achieved in combination with conventional urea/methanol injection of NO{sub 2} gas into the duct. The SOXAL process is applicable to both utility and industrial scale boilers using either high or low sulfur coal. The SOXAL demonstration Program began September 10, 1991 and is approximately 22 months in duration. During the 6 months of scheduled operations period, expected to begin January 1992, data will be collected from the SOXAL system to define: SO{sub 2} and NO{sub x} control efficiencies; Current efficiency for the regeneration unit; Sulfate oxidation in the absorber; Make-up reagent rates; Product quality including concentrations and compositions; System integration and control philosophy; and Membrane stability and performance with respect to foulants.« less

Multi-source SO2 emission retrievals and consistency of satellite and surface measurements with reported emissions

NASA Astrophysics Data System (ADS)

Fioletov, Vitali; McLinden, Chris A.; Kharol, Shailesh K.; Krotkov, Nickolay A.; Li, Can; Joiner, Joanna; Moran, Michael D.; Vet, Robert; Visschedijk, Antoon J. H.; Denier van der Gon, Hugo A. C.

2017-10-01

Reported sulfur dioxide (SO2) emissions from US and Canadian sources have declined dramatically since the 1990s as a result of emission control measures. Observations from the Ozone Monitoring Instrument (OMI) on NASA's Aura satellite and ground-based in situ measurements are examined to verify whether the observed changes from SO2 abundance measurements are quantitatively consistent with the reported changes in emissions. To make this connection, a new method to link SO2 emissions and satellite SO2 measurements was developed. The method is based on fitting satellite SO2 vertical column densities (VCDs) to a set of functions of OMI pixel coordinates and wind speeds, where each function represents a statistical model of a plume from a single point source. The concept is first demonstrated using sources in North America and then applied to Europe. The correlation coefficient between OMI-measured VCDs (with a local bias removed) and SO2 VCDs derived here using reported emissions for 1° by 1° gridded data is 0.91 and the best-fit line has a slope near unity, confirming a very good agreement between observed SO2 VCDs and reported emissions. Having demonstrated their consistency, seasonal and annual mean SO2 VCD distributions are calculated, based on reported point-source emissions for the period 1980-2015, as would have been seen by OMI. This consistency is further substantiated as the emission-derived VCDs also show a high correlation with annual mean SO2 surface concentrations at 50 regional monitoring stations.

EVALUATION AND APPLICATION OF SOX MEASUREMENT PROCEDURES FOR KRAFT RECOVERY FURNACES

EPA Science Inventory

The objective of this investigation was to determine the sulfuric acid (SO3/H2SO4) and sulfur dioxide (SO2) emissions from kraft recovery furnaces using an extractive sampling system. The Goksoyr and Ross controlled condensation technique was chosen. Equipment was designed and fa...

Vacancy-type defects in TiO2/SiO2/SiC dielectric stacks

NASA Astrophysics Data System (ADS)

Coleman, P. G.; Burrows, C. P.; Mahapatra, R.; Wright, N. G.

2007-07-01

Open-volume (vacancy-type) point defects have been observed in ˜80-nm-thick titanium dioxide films grown on silicon dioxide/4H silicon carbide substrates as stacks with high dielectric constant for power device applications, using variable-energy positron annihilation spectroscopy. The concentration of vacancies decreases as the titanium dioxide growth temperature is increased in the range from 700to1000°C, whereas grain boundaries form in the polycrystalline material at the highest growth temperatures. It is proposed that the optimal electrical performance for films grown at 800°C reflects a balance between decreasing vacancy concentration and increasing grain boundary formation. The concentration of vacancies at the silicon dioxide/silicon carbide interface appears to saturate after 2.5h oxidation at 1150°C. A supplementary result suggests that the quality of the 10-μm-thick deposited silicon carbide epilayer is compromised at depths of about 2μm and beyond, possibly by the migration of impurities and/or other defects from the standard-grade highly doped 4H silicon carbide wafer beneath the epilayer during oxidation.

Extended duration orbiter study: CO2 removal and water recovery

NASA Technical Reports Server (NTRS)

Marshall, R. D.; Ellis, G. S.; Schubert, F. H.; Wynveen, R. A.

1979-01-01

Two electrochemical depolarized carbon dioxide concentrator subsystems were evaluated against baseline lithium hydroxide for (1) the baseline orbiter when expanded to accommodate a crew of seven (mission option one), (2) an extended duration orbiter with a power extension package to reduce fuel cell expendables (mission option two), and (3) an extended duration orbiter with a full capability power module to eliminate fuel cell expendables (mission option three). The electrochemical depolarized carbon dioxide concentrator was also compared to the solid amine regenerable carbon dioxide removal concept. Water recovery is not required for Mission Option One since sufficient water is generated by the fuel cells. The vapor compression distillation subsystem was evaluated for mission option two and three only. Weight savings attainable using the vapor compression distillation subsystem for water recovery versus on-board water storage were determined. Combined carbon dioxide removal and water recovery was evaluated to determine the effect on regenerable carbon dioxide removal subsystem selection.

Outdoor air pollution and term low birth weight in Japan.

PubMed

Yorifuji, Takashi; Kashima, Saori; Doi, Hiroyuki

2015-01-01

Evidence has accumulated on the association between ambient air pollution and adverse birth outcomes. However, most of the previous studies were conducted in geographically distinct areas and suffer from lack of important potential covariates. We examined the effect of ambient air pollution on term low birth weight (LBW) using data from a nationwide population-based longitudinal survey in Japan that began in 2001. We restricted participants to term singletons (n=44,109). Air pollution concentrations during the 9months before birth were obtained at the municipality level and were assigned to the participants who were born in the corresponding municipality. We conducted multilevel logistic regression analyses adjusting for individual and municipality-level variables. We found that air pollution exposure during pregnancy was positively associated with the risk of term LBW. In the fully adjusted models, odds ratios following one interquartile range increase in each pollutant were 1.09 (95% confidence interval: 1.00, 1.19) for suspended particulate matter (SPM), 1.11 (0.99, 1.26) for nitrogen dioxide (NO2), and 1.71 (1.18, 2.46) for sulfur dioxide (SO2). Specifically, effect estimates for SPM and NO2 exposure at the first trimester were higher than those at other trimesters, while SO2 was associated with the risk at all trimesters. Nonsmoking mothers were more susceptible to SPM and NO2 exposure compared with smoking mothers. Ambient air pollution increases the risk of term LBW in a nationally representative sample in Japan. Copyright © 2014 Elsevier Ltd. All rights reserved.

Detection of Survival and Proliferation of Sulfate Reducers Under Simulated Martian Atmospheric and Soil Conditions

NASA Astrophysics Data System (ADS)

Mora, Sergio Mosquera

Numerous studies have tried to determine the survivability and proliferation of microorganisms under simulated Martian conditions. Furthermore, most of them have been focused on the ability of these microbes to cope with high brines' salt (NaCl) concentrations inherent of the Martian surface. However, there are not studies related to the ability of bacteria to survive on subsurface environments that have increasing concentrations of sulfate compounds. For this research, a group of microorganisms known as sulfate-reducing bacteria or simply sulfate reducers were chosen due to their ability to use sulfate compounds as terminal electron acceptors to produce metabolic energy, their tolerance to low temperatures (psychrophilic microbes) and their anaerobic metabolism. Moreover, the principal purpose of this study was to determine the ability of sulfate reducers to carry active metabolism under conditions similar to those present on Mars subsurface (low temperature, high concentration of sulfate compounds, anoxic atmosphere-95% carbon dioxide, low nutrients availability, among others). Furthermore, we cultivated strains of Desulfotalea psychrophila, Desulfuromusa ferrireducens and Desulfotomaculum arcticum using different concentrations of minerals. The latter (CaSO 4, MgSO4, FeSO4 and Fe2(SO4) 3) are normally found as part of the Martian subsurface components and they can act as terminal electron acceptors in sulfate respiration. Moreover, PCR amplifications of the 16S rDNA gene and the dsrAB genes were performed in order to determine the growth and survivability of the three microorganisms tested. Finally, we were able to determine that they were metabolically active at the different types and mineral concentrations under study.

Long range transport and air quality impacts of SO2 emissions from Holuhraun (Bárdarbunga, Iceland)

NASA Astrophysics Data System (ADS)

Schmidt, Anja; Witham, Claire; Leadbetter, Susan; Theys, Nicholas; Hort, Matthew; Thordarson, Thorvaldur; Stevenson, John; Shepherd, Janet; Sinnott, Richard; Kenny, Patrick; Barsotti, Sara

2015-04-01

Gas emissions from the Holuhraun eruption site in Iceland resulted in increases in observed ground level concentrations of sulphur dioxide (SO2) in the UK and Ireland during two occasions in September 2014. We present data from the Irish and UK monitoring networks along with satellite imagery which describes the temporal and spatial evolution of these pollution episodes. During both events increases in concentration were significant compared to ambient levels. The peaks were short lived, 6-12 hours, and below the World Health Organisation's 10-minute air quality standard for SO2 of 500 µg/m3, but these events show that gas from relatively low altitude volcanic emissions in Iceland can pose a hazard to north west Europe. The two pollution events serve as excellent case studies and observations from the events provide us with a unique dataset for the verification of atmospheric dispersion models. We use the atmospheric dispersion model NAME to simulate the long-range transport, removal and chemical conversion of the volcanic SO2 during September 2014. We evaluate a range of model simulations, using varying model input and physical parameters, against ground based measurements and satellite retrievals of SO2. Simulations demonstrate that the long-range ground concentrations are strongly dependent on the emission flux and the height of emission at source. This relationship is well known from similar studies of other pollution events. However this work also demonstrates a dependence on the model's vertical turbulence parameterisation and the height of the boundary layer determined from the input Numerical Weather Prediction meteorological data. For the pollution events in September 2014, we find that using a mass flux of 40 kilotons per day of SO2 gives best agreement with vertical column retrievals of SO2 from the Ozone Monitoring Instrument, which is in good agreement with initial estimates made by the Icelandic Meteorological Office. "This work is distributed under the Creative Commons Attribution 3.0 Unported License together with an author copyright. This license does not conflict with the regulations of the Crown Copyright."

Sensitivity and symptomology of marigold cultivars exposed to acute sulfur dioxide

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

Howe, T.K.; Woltz, S.S.

Thirty-nine cultivars of marigold (Tagetes spp.) were exposed to sulfur dioxide to determine their relative sensitivity. Flowering plants were fumigated at 1 ppM SO/sub 2/ for 4 hours or at 2 ppM SO/sub 2/ for 2 hours. The average foliar injury for all leaves on individual plants ranged from 42.3% for 'Crackerjack Mix' at 2 ppM SO/sub 2/ to 0.0% for 'Cupid Yellow' at 1 ppM SO/sub 2/. Foliar necrosis appeared as a gray to white marginal and/or interveinal scorch 1 day after exposure. There was a tendency for interveinal necrosis to be near the midvein. The extra-floral nectaries whichmore » line the leaf margins of marigold were scorched in 15 of the 39 cultivars. This injury may be of diagnostic value. Sepals were very sensitive to SO/sub 2/. Sepal injury appeared as a pinpoint scorch and as tip burn, and was apparent in some cultivars when no foliar injury occurred. 12 references, 1 figure, 1 table.« less

DSCOVR_EPIC_L2_O3SO2AI_01

Atmospheric Science Data Center

2018-06-29

... dioxide (SO2) from volcanic plumes, scene reflectivity, and aerosol index (AI), retrieved from the ultraviolet (UV) measurements of DSCOVR ... Access:   Order Data Parameters:  Aerosol Index (AI) Reflectivity at 340 nm Vertical Column of Ozone (O3) ...

Mechanism of SO2 removal by carbon

USGS Publications Warehouse

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.

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

EPA Science Inventory

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

Decreased abundance of crustose coralline algae due to ocean acidification

USGS Publications Warehouse

Kuffner, Ilsa B.; Andersson, Andreas J; Jokiel, Paul L.; Rodgers, Ku'ulei S.; Mackenzie, Fred T.

2008-01-01

Owing to anthropogenic emissions, atmospheric concentrations of carbon dioxide could almost double between 2006 and 2100 according to business-as-usual carbon dioxide emission scenarios1. Because the ocean absorbs carbon dioxide from the atmosphere2, 3, 4, increasing atmospheric carbon dioxide concentrations will lead to increasing dissolved inorganic carbon and carbon dioxide in surface ocean waters, and hence acidification and lower carbonate saturation states2, 5. As a consequence, it has been suggested that marine calcifying organisms, for example corals, coralline algae, molluscs and foraminifera, will have difficulties producing their skeletons and shells at current rates6, 7, with potentially severe implications for marine ecosystems, including coral reefs6, 8, 9, 10, 11. Here we report a seven-week experiment exploring the effects of ocean acidification on crustose coralline algae, a cosmopolitan group of calcifying algae that is ecologically important in most shallow-water habitats12, 13, 14. Six outdoor mesocosms were continuously supplied with sea water from the adjacent reef and manipulated to simulate conditions of either ambient or elevated seawater carbon dioxide concentrations. The recruitment rate and growth of crustose coralline algae were severely inhibited in the elevated carbon dioxide mesocosms. Our findings suggest that ocean acidification due to human activities could cause significant change to benthic community structure in shallow-warm-water carbonate ecosystems.

Six-man, self-contained carbon dioxide concentrator system

NASA Technical Reports Server (NTRS)

Powell, J. D.; Schubert, F. H.; Marshall, R. D.; Shumar, J. W.

1974-01-01

A six man, self contained electrochemical carbon dioxide concentrating subsystem was successfully designed and fabricated. It was a preprototype engineering model designed to nominally remove 6.0 kg (13.2 lb) CO2/day with an inlet air CO2 partial pressure of 400 N/sq m (3 mm Hg) and an overcapacity removal capability of 12.0 kg (26.4 lb) CO2/day. The design specifications were later expanded to allow operation at space station prototype CO2 collection subsystem operating conditions.

Biomineralized diamond-like carbon films with incorporated titanium dioxide nanoparticles improved bioactivity properties and reduced biofilm formation.

PubMed

Lopes, F S; Oliveira, J R; Milani, J; Oliveira, L D; Machado, J P B; Trava-Airoldi, V J; Lobo, A O; Marciano, F R

2017-12-01

Recently, the development of coatings to protect biomedical alloys from oxidation, passivation and to reduce the ability for a bacterial biofilm to form after implantation has emerged. Diamond-like carbon films are commonly used for implanted medical due to their physical and chemical characteristics, showing good interactions with the biological environment. However, these properties can be significantly improved when titanium dioxide nanoparticles are included, especially to enhance the bactericidal properties of the films. So far, the deposition of hydroxyapatite on the film surface has been studied in order to improve biocompatibility and bioactive behavior. Herein, we developed a new route to obtain a homogeneous and crystalline apatite coating on diamond-like carbon films grown on 304 biomedical stainless steel and evaluated its antibacterial effect. For this purpose, films containing two different concentrations of titanium dioxide (0.1 and 0.3g/L) were obtained by chemical vapor deposition. To obtain the apatite layer, the samples were soaked in simulated body fluid solution for up to 21days. The antibacterial activity of the films was evaluated by bacterial eradication tests using Staphylococcus aureus biofilm. Scanning electron microscopy, X-ray diffraction, Raman scattering spectroscopy, and goniometry showed that homogeneous, crystalline, and hydrophilic apatite films were formed independently of the titanium dioxide concentration. Interestingly, the diamond-like films containing titanium dioxide and hydroxyapatite reduced the biofilm formation compared to controls. A synergism between hydroxyapatite and titanium dioxide that provided an antimicrobial effect against opportunistic pathogens was clearly observed. Copyright © 2017 Elsevier B.V. All rights reserved.

Endogeous sulfur dioxide protects against oleic acid-induced acute lung injury in association with inhibition of oxidative stress in rats.

PubMed

Chen, Siyao; Zheng, Saijun; Liu, Zhiwei; Tang, Chaoshu; Zhao, Bin; Du, Junbao; Jin, Hongfang

2015-02-01

The role of endogenous sulfur dioxide (SO2), an efficient gasotransmitter maintaining homeostasis, in the development of acute lung injury (ALI) remains unidentified. We aimed to investigate the role of endogenous SO2 in the pathogenesis of ALI. An oleic acid (OA)-induced ALI rat model was established. Endogenous SO2 levels, lung injury, oxidative stress markers and apoptosis were examined. OA-induced ALI rats showed a markedly downregulated endogenous SO2/aspartate aminotransferase 1 (AAT1)/AAT2 pathway and severe lung injury. Chemical colorimetry assays demonstrated upregulated reactive oxygen species generation and downregulated antioxidant capacity in OA-induced ALI rats. However, SO2 increased endogenous SO2 levels, protected against oxidative stress and alleviated ALI. Moreover, compared with OA-treated cells, in human alveolar epithelial cells SO2 downregulated O2(-) and OH(-) generation. In contrast, L-aspartic acid-β-hydroxamate (HDX, Sigma-Aldrich Corporation), an inhibitor of endogenous SO2 generating enzyme, promoted free radical generation, upregulated poly (ADP-ribose) polymerase expression, activated caspase-3, as well as promoted cell apoptosis. Importantly, apoptosis could be inhibited by the free radical scavengers glutathione (GSH) and N-acetyl-L-cysteine (NAC). The results suggest that SO2/AAT1/AAT2 pathway might protect against the development of OA-induced ALI by inhibiting oxidative stress.

Air pollution and heart failure: Relationship with the ejection fraction

PubMed Central

Dominguez-Rodriguez, Alberto; Abreu-Afonso, Javier; Rodríguez, Sergio; Juarez-Prera, Ruben A; Arroyo-Ucar, Eduardo; Gonzalez, Yenny; Abreu-Gonzalez, Pedro; Avanzas, Pablo

2013-01-01

AIM: To study whether the concentrations of particulate matter in ambient air are associated with hospital admission due to heart failure in patients with heart failure with preserved ejection fraction and reduced ejection fraction. METHODS: We studied 353 consecutive patients admitted into a tertiary care hospital with a diagnosis of heart failure. Patients with ejection fraction of ≥ 45% were classified as having heart failure with preserved ejection fraction and those with an ejection fraction of < 45% were classified as having heart failure with reduced ejection fraction. We determined the average concentrations of different sizes of particulate matter (< 10, < 2.5, and < 1 μm) and the concentrations of gaseous pollutants (carbon monoxide, sulphur dioxide, nitrogen dioxide and ozone) from 1 d up to 7 d prior to admission. RESULTS: The heart failure with preserved ejection fraction population was exposed to higher nitrogen dioxide concentrations compared to the heart failure with reduced ejection fraction population (12.95 ± 8.22 μg/m3 vs 4.50 ± 2.34 μg/m3, P < 0.0001). Multivariate analysis showed that nitrogen dioxide was a significant predictor of heart failure with preserved ejection fraction (odds ratio ranging from (1.403, 95%CI: 1.003-2.007, P = 0.04) to (1.669, 95%CI: 1.043-2.671, P = 0.03). CONCLUSION: This study demonstrates that short-term nitrogen dioxide exposure is independently associated with admission in the heart failure with preserved ejection fraction population. PMID:23538391

Effect of wine inhibitors on the proteolytic activity of papain from Carica papaya L. latex.

PubMed

Benucci, Ilaria; Esti, Marco; Liburdi, Katia

2015-01-01

The influence of potential inhibitors naturally present in wine on the proteolytic activity of papain from Carica papaya latex was investigated to evaluate its applicability in white wine protein haze stabilization. Enzymatic activity was tested against a synthetic tripeptide chromogenic substrate in wine-like acidic medium that consisted of tartaric buffer (pH 3.2) supplemented with ethanol, free sulfur dioxide (SO2 ), grape skin and seed tannins within the average ranges of concentrations that are typical in wine. The diagnosis of inhibition type, performed with the graphical method, demonstrated that all of tested wine constituents were reversible inhibitors of papain. The strongest inhibition was exerted by free SO2 , which acted as a mixed-type inhibitor, similar to grape skin and seed tannins. Finally, when tested in table white wines, the catalytic activity of papain, even when if it was ascribable to the hyperbolic behavior of Michaelis-Menten equation, was determined to be strongly affected by free SO2 and total phenol level. © 2014 American Institute of Chemical Engineers.

Effects of water vapor on flue gas conditioning in the electric fields with corona discharge.

PubMed

Liqiang, Qi; Yajuan, Zhang

2013-07-15

Sulfur dioxide (SO2) removal via pulsed discharge nonthermal plasma in the absence of ammonia was investigated to determine how electrostatic precipitators (ESPs) can effectively collect particulate matter less than 2.5μm in diameter from flue gas. SO2 removal increased as water vapor concentration increased. In a wet-type plasma reactor, directing a gas-phase discharge plasma toward the water film surface significantly enhanced the liquid-phase oxidation of HSO3(-) to SO4(2-). Comparisons of various absorbents revealed that the hydroxyl radical is a key factor in plasma-induced liquid-phase reactions. The resistivity, size distribution, and cohesive force of fly ash at different water vapor contents were measured using a Bahco centrifuge, which is a dust electrical resistivity test instrument, as well as a cohesive force test apparatus developed by the researchers. When water vapor content increased by 5%, fly ash resistivity in flue gas decreased by approximately two orders of magnitude, adhesive force and size increased, and specific surface area decreased. Therefore, ESP efficiency increased. Copyright © 2013 Elsevier B.V. All rights reserved.

CO 2 hydrogenation to formate and methanol as an alternative to photo- and electrochemical CO 2 reduction

DOE PAGES

Wang, Wan -Hui; Himeda, Yuichiro; Muckerman, James T.; ...

2015-09-03

In this study, carbon dioxide is one of the end products of combustion, and is not a benign component of the atmosphere. The concentration of CO 2 in the atmosphere has reached unprecedented levels and continues to increase owing to an escalating rate of fossil fuel combustion, causing concern about climate change and rising sea levels. In view of the inevitable depletion of fossil fuels, a possible solution to this problem is the recycling of carbon dioxide, possibly captured at its point of generation, to fuels. Researchers in this field are using solar energy for CO 2 activation and utilizationmore » in several ways: (i) so-called artificial photosynthesis using photo-induced electrons; (ii) bulk electrolysis of a CO 2 saturated solution using electricity produced by photovoltaics; (iii) CO 2 hydrogenation using solar-produced H 2; and (iv) the thermochemical reaction of metal oxides at extremely high temperature reached by solar collectors. Since the thermodynamics of CO 2 at high temperature (> 1000 ºC) are quite different from those near room temperature, only chemistry below 200 ºC is discussed in this review.« less

Exposure to air pollution near a steel plant and effects on cardiovascular physiology: a randomized crossover study.

PubMed

Liu, Ling; Kauri, Lisa Marie; Mahmud, Mamun; Weichenthal, Scott; Cakmak, Sabit; Shutt, Robin; You, Hongyu; Thomson, Errol; Vincent, Renaud; Kumarathasan, Premkumari; Broad, Gayle; Dales, Robert

2014-03-01

Iron and steel industry is an important source of air pollution emissions. Few studies have investigated cardiovascular effects of air pollutants emitted from steel plants. We examined the influence of outdoor air pollution in the vicinity of a steel plant on cardiovascular physiology in Sault Ste. Marie, Canada. Sixty-one healthy, non-smoking subjects (females/males=33/28, median age 22 years) spent 5 consecutive 8-hour days outdoors in a residential area neighbouring a steel plant, or on a college campus approximately 5 kilometres away from the plant, and then crossed over to the other site with a 9-day washout. Mid day, subjects underwent daily 30-minute moderate intensity exercise. Blood pressure (BP) and pulse rate were determined daily and post exercise at both sites. Flow-mediated vasodilation (FMD) was determined at the site near the plant. Air pollution was monitored at both sites. Mixed-effects regressions were run for statistical associations, adjusting for weather variables. Concentrations of ultrafine particles, sulphur dioxide (SO2), nitrogen dioxide (NO2) and carbon monoxide (CO) were 50-100% higher at the site near the plant than at the college site, with minor differences in temperature, humidity, and concentrations of particulate matter ≤2.5 μm in size (PM2.5) and ozone (O3). Resting pulse rate [mean (95% confidence interval)] was moderately higher near the steel plant [+1.53 bpm (0.31, 2.78)] than at the college site, male subjects having the highest pulse rate elevation [+2.77 bpm (0.78, 4.76)]. Resting systolic and diastolic BP and pulse pressure, and post-exercise BP and pulse rate were not significantly different between two sites. Interquartile range concentrations of SO2 (2.9 ppb), NO2 (5.0 ppb) and CO (0.2 ppm) were associated with increased pulse rate [0.19 bpm (-0.00, 0.38), 0.86 bpm (0.03, 1.68), and 0.11 bpm (0.00, 0.22), respectively], ultrafine particles (10,256 count/cm(3)) associated with increased pulse pressure [0.85 mmHg (0.23, 1.48)], and NO2 and CO inversely associated with FMD [-0.14% (-0.31, 0.02), -0.02% (-0.03, -0.00), respectively]. SO2 during exercise was associated with increased pulse rate [0.26 bpm (0.01, 0.51)]. Air quality in residential areas near steel plants may influence cardiovascular physiology. Copyright © 2013 Elsevier GmbH. All rights reserved.

Reference and Equivalent Methods Used to Measure National Ambient Air Quality Standards (NAAQS) Criteria Air Pollutants - Volume I

EPA Science Inventory

There are a number of Federal Reference Method (FRM) and Federal Equivalent Method (FEM) systems used to monitor the six criteria air pollutants (Lead [Pb], Carbon Monoxide [CO], Sulfur Dioxide [SO2], Nitrogen Dioxide [NO2], Ozone [O3], Particulate Matter [PM]) to determine if an...