• Journal of Environmental Health Sciences
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• v.10 no.2
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• pp.69-77
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• 1984

Air pollution has been one of the severe problems in city area. Sulfur dioxide is the major pollutant among the air pollutants. And the lichen as a botanical indicator have been used to predict the air pollution level. This study was carried out to evaluate the air pollution level in Taejon area through the field survey which were checked lichen status and sulfur dioxide content in the atmosphere. The results were as follows 1. The average sulfur dioxide content in Taejon area was 0.031ppm. The comparison of measurement methods were regression equation, Y= 0.357$\times$+0.014 and correlation factor, r = 0.771. 2. The maximum point of the SO$_2$ level was site No. 2(Daehwa-Dong), 0.087 ppm and the minimum, site No. 8 (Doma 2-Dong), 0.009ppm. 3. Total amounts of sulfur dioxide yearly emitted from Taejon area by fuel consumption estimated 29829.6 tons. 4. The relationship between degree of lichen and sulfur dioxide contents were 0.000~0.020ppm : Zone No. 2 0.020~0.060ppm : Zone No. 1 over 0.060ppm : Zone No. 0

• Journal of Environmental Impact Assessment
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• v.8 no.4
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• pp.73-79
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• 1999

This study was conducted as a preliminary study for the mitigation of acid rain which has been a serious environmental problem in both regional and global scales. In this study, sulfur dioxide emission was estimated at city and gun(county) level. Also, this study represents the estimated sulfur dioxide emission with using a geographical information system which includes administrative boundaries. The results of this study are expected to serve as a sulfur dioxide emission mitigation policy guidance and a basis of a future emission model and a comprehensive global warming model. Moreover, thanks to the geographical information system, the results are also expected to help carrying out clear policy goals and setting up sulfur dioxide emission mitigation measures in regional environmental planning processes, which currently have been implemented in some cities and counties in Korea.

• The Korean Journal of Mycology
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• v.19 no.4
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• pp.285-291
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• 1991

Sulfur dioxide discharged from the factories in Yeochun industrial complex severely damaged to the growth of oyster mushrooms. The continuous monitoring indicated that high concentration of sulfur dioxide was repeatedly detected in Kwang-Yang and Seung-Ju. The first injury symptoms on the mushroom fruit bodies were observed a day later when sulfur dioxide was detected over 300 ppb. Under the high concentration of sulfur dioxide exposure, the young fruit bodies showed blight and sudden death and the mature fruit bodies turned to blue-brown and frequently progressed to blight. The symptoms at Spring cropping were more severe than those at Autumn cropping. The severity was associated with the frequency of sulfur dioxide monitored. However, sulfur content in the mushroom fruit bodies and culture media did not show clear differences between the injured mushroom from Yeochun industrial complex areas and normal ones from no damaged areas.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.10 no.5
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• pp.1133-1140
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• 2009

The purpose of this study is to determine the most efficient method of removing sulfur dioxide from traditional herbal medicine (hanyak) by slow boiling using a traditional pipkin and an electronic slow boiler. By boiling a hanyak batch containing] 56.4ppm of sulfur dioxide for one hour using a traditional pipkin, 96.7 percent of the sulfur dioxide was removed, while two hours of slow boiling removed ]00 percent. Among different cover materials placed over the pipkin during the slow boiling process including the traditional Korean paper (hanji), regular hanji, filter paper and regular paper, the traditional hanji produced the best performance of sulfur dioxide removal. The initial pH level of the traditional hanji was] 0.03. After one hour of slow boiling hanyak batches in a traditional pipkin covered with traditional hanji, where each batch contained sulfur dioxide of 48ppm, 193ppm, 753ppm and 1,506ppm respectively, the pH level of the hanji cover material was reduced to 9.37, 9.14, 8.9 and 8.03 in respective cases. Our experiment using an electronic medicine slow boiler showed 82.8 percent removal of sulfur dioxide after one hour of slow boiling a hanyak batch containing 753ppm of sulfur dioxide. When hanyak batches were boiled by placing traditional hanji, filter paper, active carbon and hardwood charcoal separately in the middle area within the electronic slow boiler, the sulfur dioxide removal rate was 73.6 percent, 72.8 percent, 73.9 percent and 69.5 percent, respectively. When charcoal was added so as to remove toxic materials from the hanyak, its presence impeded the sulfur dioxide flow and thus reduced the removal efficiency contrary to our anticipation.

• Journal of Power System Engineering
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• v.19 no.2
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• pp.64-69
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• 2015

Marine diesel engines with high thermal efficiency and fuel diversity used for propulsive power have been taking charge of important position on marine transport. However, marine environment has recently focused on emissions such as nitrogen oxide and sulfur oxide which is generated from combustion of low grade fuels. EGR(Exhaust gas recirculation) system is one of effective methods to reduce the nitrogen oxide emission from marine diesel engines. In general, it is considered that recirculating gas influences fuel combustion and emissions in diesel engines. However, along with positive effects of EGR, the EGR system using fuels of including high sulfur concentration should be considered about re-combustion and activation of sulfur dioxide in recirculating gas. Therefore, in experimental study, an author investigates effects of sulfur dioxide mixture concentration in intake air on combustion and exhaust emission characteristics in a direct injection diesel engine. In results, change of sulfur dioxide concentrations in intake air had negligible impact on combustion chamber pressure, rate of heat release and emissions compared with effects of oxygen decreasing and carbon dioxide increasing of EGR.

• Korean Journal of Medicinal Crop Science
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• v.21 no.2
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• pp.124-129
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• 2013

This study was conducted to investigate the residual contents of sulfur dioxide ($SO_2$) in commercial medicinal herbs in Korea in 2012. Among a total of 136 samples of 16 different kinds of herbs, 86 samples (15 Kinds) were domestic, and 50 samples (14 Kinds) were imported. Sulfur dioxide in the samples was measured by a modified Monier-Williams method. Of the 136 samples, 17 samples (12.5%, 6 Kinds) failed to meet the regulations for sulfur dioxide residues of KFDA in medicinal herbs. Among 17 unsuitable samples, 7 samples (8.1%, 3 Kinds) were domestic, and 10 samples (20.0%, 6 Kinds) were imported. The highest amount of sulfur dioxide residues was 3,167.94 mg/kg (Lycii Fructus) in the domestic samples. The detection frequency of sulfur dioxide by medicinal herb parts used, Rhizoma 25.7%, Flos 20.0%. Cortex 12.5%, Radix 15.3%, Fructus 7.6%, p-value 0.011. This results will be used as a basic data for the future legislation on the quality estimation and safety of medicinal herbs.

• Membrane Journal
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• v.16 no.3
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• pp.196-203
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• 2006

A flue gas emission known to cause an acid rain, containing sulfur dioxide, is tightly controlled by a regulation. The membrane contactor could be one of the alternatives which might be useful technologies for better performance of desulfurization. The fundamental sulfur dioxide separation data were obtained by a flat membrane contactor so that they could be utilized for the full scale membrane contactor. The separation of sulfur dioxide was measured in terms of the concentration of NaOH absorbent, the concentration of sulfur dioxide, the feed flow rate and different membrane materials. As the concentration of absorbent increased, the removal efficiency increased. By increasing the concentration of sulfur dioxide, the removal efficiency decreased. As the feed flow rate increased, it was observed that the removal efficiency decreased. Finally, the effect of the membrane material on separation was found to be negligible.

• Korean Journal of Food Science and Technology
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• v.32 no.3
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• pp.544-549
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• 2000

This study was performed to compare optimum analytical method for the contents of naturally occurring sulfur dioxide in foods and to investigate the contents of sulfur dioxide in foods in order to provide a fundamental data when distinguish between added and naturally occurring sulfur dioxide. The determination of the contents of sulfur dioxide in foods from the 20 kinds, 180 cases of samples has been analyzed by the optimized Monier-Williams method, modified Rankine method and Acid Distillation/Ion Chromatography. As a result of the study, the contents of naturally occurring sulfur dioxide in foods by the optimized Monier-Williams method showed from 1.02 to 43.87 ppm and highly content of 43.87, 15.37, 11.50, 11.21 and 10.60ppm were observed in garlic, platicodon, green onion, cabbage and onion, the others were less than 10.00ppm. The sulfur dioxide contents in green onion and garlic by modified Rankine method were showed to be 2.87 and 6.14ppm, respectively, the others were detected less than 2.50ppm. The contents of sulfur dioxide by Acid Distillation/Ion Chromatography showed 15.43, 9.82, 5.74, 5.37, 2.14 and 0.49ppm in garlic, cabbage, green onion, onion, potato and apple, respectively and the others were not detected. And the contents of sulfur dioxide in green onion, onion, cabbage and garlic showed higher levels of sulfur dioxide in these foods than the others because of the naturally occurring sulfur containing compounds. The optimized Monier-Williams method, which is the of official analytical method of Korean Food Code, was suitable for monitoring of sulfur dioxide of most foods. Acid Distillation/Ion Chromatography was thought to be adequate for sulfur containing foods such as green onion, onion and cabbage. In order to distinguish between added and naturally occurring sulfur dioxide, it is though to be need of the fundamental data for the contents of sulfur dioxide in sulfite-free foods and continue the investigation for it.

• Membrane Journal
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• v.25 no.3
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• pp.248-255
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• 2015

Aminated polyetherimide membrane synthesized in the laboratory according to amine ratio was used for measurement of gas permeability, diffusivity, and solubility about carbon dioxide, nitrogen, methane, oxygen, and sulfur dioxide with Time-lag method at room temperature. Generally, gas permeability is totally decreased because the more amination rate reacted to the main chain of amine groups, the more intermolecular space became narrow. However, gas permeability of sulfur dioxide was increased due to combination of sulfur dioxide and amine groups have acid and base properties respectively. Diffusivity and solubility of dry gas are totally decreased excluding sulfur dioxide as increasing amination rate. In case of sulfur dioxide, however, diffusivity as well as solubility was increased as increasing amination rate. Selectivity of carbon dioxide/nitrogen showed 60 when amination rate was 3. In case of humid gas, gas permeability of carbon dioxide was 70 barrer when relative humidity showed 100, and selectivity with nitrogen approximately showed 18.

• The Korean Journal of Mycology
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• v.11 no.4
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• pp.163-167
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• 1983

Oyster mushroom, Pleurotus ostreatus, was exposed to 0.625, 1.25, 2.5 and 5.0 ppm $SO_2$ for 15, 30, 60, 120 and 180 minutes at the tiny button stage in order to study the effect of sulfur dioxide on growth and cap discoloration of the mushroom. The cap color was changed from grey to greyish blue at low dosage of sulfur dioxide, and with the lapse of exposing time and rasing sulfur dioxide concentration up, the color was changed to light brown and dark brown. The cap dicoloration was begun by the exposure of sulfur dioxide to 0.625 ppm for 120 minutes, to 1.25 ppm for 30 minutes and to 2.5 ppm for 15 minutes. By the exposure of sulfur dioxide to 1.25 ppm for 120 minutes, to 2.5 ppm for 30 minutes, its growth was inhibited, but the fruit body was died by the exposure of the gas to 2.5 ppm for 180 minutes and to 5.0 ppm for 60 minutes. Sulfur dioxide inhibited conspicuously the development of basidia and basidiospores of the mushroom and 20 to 25 percent of basidiospores formed were abnormal. Ethylene production by mushroom exposed to sulfur dioxide was not recognized.