• Journal of Korean Society for Atmospheric Environment
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• v.6 no.1
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• pp.51-56
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• 1990

This Study shows the effect of the district heating on the $SO_2$ concentration reduction. In order to analyze the effect of the district heating, three alternatives were set up as follows; Alternative I represented present central heating system, and Alternative II and Alternative III represented district heating system of which the scale were different from. The concludions of this study are as follows; In case of the Alternative II and III, annual average $SO_2$ concentration are reduced by 9.0% and 14.6% respectively, and winter season $SO_2$ concentrations are reduced by 12.2% and 15.8% respectively, at the highest points. The average reduction rates of $SO_2$ concentration in the district heating area are about the same as the reduction rates at the highest points. Also, it was found that using the district heating system, the ground level $SO_2$ concentrations could be reduced within the area of 5 to 10 km radius.

• Journal of Environmental Health Sciences
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• v.11 no.1
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• pp.9-14
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• 1985

This experiment was carried out to study on the effect of SO$_2$ gas to chemical composition of tobacco leaves during flue-curing. The results were as follows: SO$_2$ gas in briquet was the major factor to damage with tobacco leaves. The damage only occured in a presence of moisture in tobacco leaves, it did not occured after color fix'lng stage which is a little leaf moisture. The danger of damage to tobacco leaves lies in 10ppm of SO$_2$ gas concentration. Follow with the SO$_2$ gas concentration increased, sugar and nitrogen contents became higher, polyphenol contents were loss, and the quality of tobacco leaves declined.

• Korean Journal of Agricultural Science
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• v.9 no.2
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• pp.453-460
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• 1982

In order to investigate the effect of $AgNO_3$ pretreatment on reducing $SO_2$ injury in leaves of Forsythia koreana, changes of pH, chlorophyll content, peroxidase activity, sulfur content, and stomatal behaviour in leaves were examined. 1. $AgNO_3$ sprayed at 200 ppm or above increased black spot development in lower epidermis of leaves. But pretreatment with 100 ppm $AgNO_3$ significantly reduced de foliation and visible injury rate of leaves exposed to $SO_2$. 2. $AgNO_3$ pretreatment prevented lowering pH and decreasing chlorophyll content induced by $SO_2$ injury in leaves. But both $AgNO_3$ pretreatment and $SO_2$ exposure increased peroxidase activity in leaves. 3. $AgNO_3$ pretreatment did not affect reducing $SO_2$ absorption and stomatal opening in leaves exposed to $SO_2$.

• Journal of the Korean Ceramic Society
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• v.30 no.1
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• pp.7-16
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• 1993

Effect of sulfate on the reactionof C3S formation in presence of clinker melt and its appearance in clinker were investigated, using (NH4)2SO4 and CaSO4 as sulfate sources. When (NH4)2SO4 and CaSO4 were added, both showed the similar results, 1.0wt% of sulfate could promoted the reaction of C3S formation, however for its content of more than 2.0wt%, the formation of C3S was prevented. Residual limit of sulfate to C3S formation is about 1.4wt%. Appearances of sulfate were C4A3l and CaSO4 in interstitial phase. For the addition of (NH4)2SO4 or CaSO4 of 20wt%~4.0wt%, C3S grains showed the hypertrophic growth. We might consider that, because sulfate reduced the surface tension and viscosity of the clinker melt, C3S crystals were precipitated below 140$0^{\circ}C$, and the crystlas of C3S were coalesced and linked in the same crystallographical direction with increasing temperature becuase of their rapid growth rate.

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2004.11a
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• pp.451-452
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• 2004

• Transactions of the Korean hydrogen and new energy society
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• v.17 no.4
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• pp.371-378
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• 2006

Effect of $(NH_4)_2SO_4$ precipitation and heat-treatment on hydrogenase which was extracted from the cytoplasmic fraction of the phototrophic purple sulfur bacterium Thiocapsa roseopersicina NCIB 8347 was studied. Crude enzyme extract was prepared by centrifugation($28,000{\times}g$, $400,000{\times}g$) after sonication of cells grown under photosynthetic condition for 96 hrs. Various conditions of $(NH_4)_2SO_4$ precipitation and heat-treatment were examined and the effect of protein concentration was analyzed by SDS-electrophoresis between the treatments. Optimum conditions for $(NH_4)_2SO_4$ precipitation and heat-treatment for evolution hydrogenase activity were 40-60% saturation and $60^{\circ}C$ for 20 min, respectively, which exhibited the specific hydrogenase activity of 0.78 U/mg-protein. Specific hydrogenase activity was decreased to 31.6% when the heat-treatment at $60^{\circ}C$ increased from 20 min to 5 hrs.

• Journal of the Korean Society of Food Science and Nutrition
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• v.26 no.6
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• pp.1096-1101
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• 1997

Soy curd was prepared using imported soybean(U.S.grade A) and changes in quality were evaluated using different types and mixtures of coagulants(CaCl$_2$, CaSO$_4$, MgCl$_2$, MgSO$_4$, and glucono-$\delta$-lactone). Quality of soy curd was determined by rheological properties, yield, and color. Based upon the characteristics of each coagulant, mixtures of two coagulants were prepared in various ratios. The mixture of CaSO$_4$or MgCl$_2$with glucono-$\delta$-lactone(GDL), and that of CaSO$_4$or MgCl$_2$with MgSO$_4$resulted in soy curd of good quality in terms of rheological properties and yield.

• Korean Journal of Environmental Agriculture
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• v.1 no.1
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• pp.71-73
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• 1982

$SO_2$ injury was higher in the foliage of several ornamental plants when treated in July than in August or September. Spray of daminozide at 2,500 ppm 7 days before $SO_2$ fumigation had no effect on $SO_2$ injury whereas MH pretreatment increased $SO_2$ injury in Hibiscus syriacus.

• Journal of the Korean Applied Science and Technology
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• v.27 no.4
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• pp.470-474
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• 2010

Various anti-scattering agents for suppression of dust scattering at waste depository were compared in this study. Based on the price, easy of usage, and no toxicity, 1% of $Al_2(SO_4)_3$ was selected as surface hardening agents. Only lower than 2% of total weight were flied when wind speed was monthly maximum velocity during 1 hr. These results were quite good with comparison of S anti-scattering agents which was made by C company in Korea. When $Al_2(SO_4)_3$ was spread, the surface waste became hard therefore the effect of suppression of scattering dust was long lasting. It was recommend that 2% of $Al_2(SO_4)_3$ was spread to keep suppression of scattering dust when sudden gust of wind such as natural disaster was occurred.

• Proceedings of the KIEE Conference
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• 1998.07e
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• pp.1794-1796
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• 1998

In this study, the $SO_2$ addition effect on NOx removal has been conducted from a combustion flue gases by the do corona discharge-activated radical shower systems. The simulated flue gases were consisted of NO-O_2-$N_2$, NO-$CO_2-N_2-O_2$ and $NO-SO_2-CO_2-Na-O_2$([NO]o:200ppm and $[SO_2]o$:800ppm). The injection gases used as radical source gases were $NH_3$-Ar-air. $SO_2$ and NOx removal efficiency and the other by-products were measured by Fourier Transform Infrared(FTIR) as well as $SO_2$. NOx and $NO_2$ gas detectors. By-product aerosol particles were also observed by Condensation Nucleation Particle Counter(CNPC) and SEM images after sampling. The results showed that asignificant aerosol Particle formation was observed during a removal operation in corona radical shower systems. The NOx removal efficiency significantly increased with increasing applied voltage and $NH_3$ molecule ratio. The $SO_2$ removal efficiency was not significantly effected by applied voltage and slightly increased with increasing $NH_3$ molecule ratio. The NOx removal efficiency for NO-$SO_2-CO_2-N_2-O_2$ was better than that for NO-$CO_2-N_2-O_2$.