• 한국대기환경학회지
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• 제7권1호
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• pp.49-53
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• 1991

Relations of urban heat island and air pollution are analyzed by using $SO_2$ concentration data (winter season in 1985) from 10 sites of Seoul area and differences of wind speed and air temperature in urban and rural area. Urban heat island is developed when daily mean wind speed at urban site is lower than 1.5m/sec or in the interval of 3.0 $\sim$ 3.5m/sec. When differences between urban and rural air temperature is greater than the overall average of those differences, $SO_2$ concentrations of those above-average differences are 1.3 $\sim$ 1.8 times higher than those of below-average differences. The trends are shown obviously at north-eastern area of Seoul (Gilum Dong, Ssangmun Dong, Myeonmog Dong). When intensity of Urban Heat Island is weak, $SO_2$ concentration was reduced in propotion to a rise of wind speed. But $SO_2$ concentration is on the partial increase in spite of a rise of wind speed when intensity of urban heat island is strong.

• 한국대기환경학회지
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• 제9권2호
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• pp.147-153
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• 1993

From March 1990 to August 1991, every each 5mm bulk precipitation samples were collected at one residental area in Taejon City to investigate chemical characteristics of acid rain. Major ion concentrations of rain samples $(pH, SO_4^{2-}, NO_3^-, CL^-, NH_4^+, Na^+, K^+, Ca^{2+}, Mg^{2+})$ were analysed and compared with the concentration of air pollutants (T. S. P, $SO_2, NO_x$) that were measured by Ministry of Environment. The results of statistical analysis are as followings. Rain pH was relatively high on October and January and relatively low on August, November and February. Major anion is sulfate, and it's concentration is 2.36 times higher than nitrate's, and major cations are ammonium, sodium and calcium ion. Monthly variation of sulfate and calcium concentrations are higher than the others. Ion concentration and rain pH were correlated negatively with rainfall amount. Major ions in rain samples were $SO_4^{2-}, NO_3^-, NH_4^+, Ca^{2+}$ and regression equations are proposed by multiple regression of measured data. Also, regression equation between air pollutants(T. S. P, $SO_2$) and $SO_4^{2-}, Na^+, K^+, Ca^{2+}, Mg^{2+} ions in rain samples were made. From this wer can predict rain pH.

• 한국대기환경학회지
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• 제34권5호
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• pp.651-658
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• 2018

Particulate matter (PM) emitted from fossil fuel-combustion facilities can be classified as either filterable or condensable PM. The U.S. Environmental Protection Agency (EPA) defined condensable PM as material that is in the phase of vapor at the stack temperature of the sampling location which condenses, reacts upon cooling and dilution in the ambient air to form solid or liquid in a few second after the discharge from the stack. Condensable PM passed through the filter media and it is typically ignored. But condensable PM was defined as a component of primary PM. This study investigates the change of condensable PM according to the variation in the sulfur dioxide of combustion gas. Domestic oil boilers were used as the source of emission ($SO_2$) and the level of $SO_2$ concentration (0, 50, 80, and 120 ppm) was adjusted by diluting general light oil and marine gas oil (MGO) that contains sulfur less than 0.5%. Condensable PM was measured as 2.72, 6.10, 8.38, and $13.34mg/m^3$ when $SO_2$ concentration in combustion gas were 0, 50, 80, and 120 ppm respectively. The condensable PM tended to increase as the concentration of $SO_2$ increased. Some of the gaseous air pollutants emitted from the stack should be considered precursors of condensable PM. The gas phase pollutants which converted into condensable PM should reduced for condensable PM control.

• 한국농공학회:학술대회논문집
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• 한국농공학회 2000년도 학술발표회 발표논문집
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• pp.531-535
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• 2000

This study was carried out to investigate water quality of streamflow in a forest land. We measured discharges and the concentration of streamflow for T-N, T-P, COD, cations(Na$\^$+/, K$\^$+/, Ca$\^$2+/, Mg$\^$2+/), and anions(CI$\^$－/, SO$\_$4/$\^$2-/). The average concentration of pollutants were extremely low, such as 0.4mg/$\ell$ for T-N, 0.02 mg/$\ell$ for T-P and 2.68mg/$\ell$for COD. The concentration of cations have a tendency to decrease with increasing discharge, while the concentration of SO$\_$4/$\^$2-/) increase with increasing discharge. It was found that the average concentration of Ca$\^$2+/ was highest and that of K$\^$+/ was lowest among cations.

• Korean Chemical Engineering Research
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• 제46권3호
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• pp.521-528
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• 2008

중공사막 접촉기에 적절한 PVDF 중공사막을 상전이 공정에 의하여 제조하였으며, SEM 과 기체투과도에 의하여 그 특성을 분석하였다. 벤치규모 중공사막 접촉기에서 $SO_2$ 제거를 위한 흡수제는 수산화나트륨 수용액을 사용하였다. 기체는 shell side, 액체는 lumen side로 흐르는 counter-current로 실험하였으며, 흡수제의 농도, 기체의 유속, 액가스비, 유입 $SO_2$ 농도에 따른 영향을 알아보았으며, 수학적 모델링에 의해 막 물질전달계수($k_m$)를 측정하였다. 흡수제의 농도와 액기비가 증가함에 따라 기-액 계면에서 충분한 알칼리도가 제공되므로, 액체막 저항이 감소하며, 총괄물질전달 용량계수는 증가하였다. 기체유속이 증가함에 따라 기체막저항은 감소하게 되므로 총괄물질전달 용량계수는 증가하였다.

• 한국환경보건학회지
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• 제17권1호
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• pp.1-12
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• 1991

The atmospheric SO$_{2}$ concentrations and water soluble sulfur contents in Ginkgo biloba were measured and analyzed in auto-measuring station, Kwangleung, and Yongmun from August 5 to October 21, 1990. The results of the study are as follows: 1. Atmospheric SO$_{2}$ concentrations between the seoul area(Pulkwang, Ssangmun, Myonmok, Oilurn) in which the concentrations exceeded the air quality standards and the surburb of seoul (Kwangleung, Yongmun) revealed the significant difference (p<0.01). 2. Water soluble sulfur contents in Ginkgo biloba in autumn were higher than those in Ginkgo biloba in summer (p<0.01). Water soluble sulfur contents in leaves showed a significant difference between seoul and its surburb(p<0.01). 3. Correlation between atmospheric SO$_{2}$ concentration and water soluble sulfur content of Ginkgo biloba in autumn was as follow Y=0.2714+9.8123 X, r=0.6362 (X: Airborne SO${_2}$ Concentration according to sampling location, Y: Water Soluble Sulfur Contents)

• 한국산학기술학회논문지
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• 제9권3호
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• pp.779-786
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• 2008

본 연구에서는 1998년부터 2006년까지 9년 동안의 서산 지역 대기오염물질 농도 변화 특성을 조사하였다. 조사 결과, 최근 3년 동안 CO와 $O_3$을 제외한 $SO_2,\;NO_2$ 및 PM-10은 농도 변화가 거의 없는 안정화 단계를 보였다. $NO_2$, CO 및 $SO_2$의 월평균농도 변화는 여름철에 감소하다. 겨울철에 증가하는 경향을 보였으며 $O_3$과 PM-10은 봄철에 높은 농도를 보이며, 강수가 집중되는 여름철에 가장 낮은 농도분포를 보였다. 2006년 12월까지 오존의 1시간 기준치인 0.1 ppm을 초과한 횟수는 동문동이 68회, 독곶리 93회였고 8시간 기준치인 0.06 ppm을 초과한 횟수는 동문동 210회, 독곶리 213회였다. 또한 미세먼지의 경우 24시간기준인 $150{\mu}g/m^3$을 초과한 횟수가 동문동 25회, 독곶리 54회로 나타났다.

• 한국대기환경학회지
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• 제16권4호
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• pp.399-408
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• 2000

This study evaluated the SO2 adsorption characteristics using a continous moving bed system. Natural manganese oxide (NMO) reaction condition such as L/D the starting time of the NMO feed, feed rate, and flow rate of simulated flue gas, and NMO size were tested. The results showed that optimum L/D was 1.0 in this moving bed system. The higher the feeding rate was the higher the SO2 removal efficiency was and the higher the flow rate of simulated flue gas was the shorter the time to reach the euqilibirum concentration was. The final SO2 con-centration when it reaches the equilibrium concentration was not affected by the starting time of the NMO feed.

• 한국대기환경학회지
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• 제12권1호
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• pp.91-99
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• 1996

Ozone, sulfur dioxide, and nitrogen oxides were measured at Kosan, Cheju Island, Korea during the period of March 11 .sim. April 19, 1994. During the measurement period, the average SO$_{2}$ and NOx concentrations were about 0.97 ppb and 3.5 ppb, respectively. Average NO concentration was below the detection limit and thus the effect of NO during the period was negligible. The concentrations of SO$_{2}$ and Nox were lower than those at other urban area in Korea but higher than other remote areas in the world. Average $O_{3}$ concentration for the period was about 55 ppb, slightly higher than or comparable to those at remote marine areas in the world. Detailed analyses of trend of gaseous species concentrations show that the effects of local NO emission sources for NOx concentration were significant during the period, while those of local SO$_{2}$ emission sources were not high. Backward trajectory analysis results show that when SO$_{2}$ or $O_{3}$ concentration was higher than the average concentrations, the air parcels were transported from China.

• 한국미생물·생명공학회지
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• 제17권3호
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• pp.247-251
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• 1989

여러가지 염이 sisomicin 발효에 미치는 영향에 대해 살펴본 결과, CoCl$_2$만이 항생물질 생성의 대사반응에 cofactor로서 작용하였으며 16.8 $\mu$M에서 최대항생물질의 수율이 얻어졌다. 한편, 앞의 경우보다 훨씬 높은 염농도에서 ZnSO$_4$, KH$_2$PO$_4$, FeSO$_4$그리고 MgSO$_4$가 각각 발효배지에 첨가되었다. ZnSO$_4$와 KH$_2$PO$_4$는 전혀 효과가 없었으나 FeSO$_4$는 약간 항생물질 수율의 향상을 가져왔다. 그러나 MgSO$_4$의 경우, 매우 높은 염농도에서도 균체생육의 저해가 약간 일어났으며, 최종 항생물질의 수율은 100% 이상 증가되었다. 이러한 결과는 부분적으로 발효 중 균체내에 생성된 항생물질이 균체외로 유출되는 효과가 증진된 것에 기인한다.