• 공업화학
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• 제3권4호
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• pp.722-729
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• 1992

몇 종류의 산화물을 혼합하여 그 장점들이 촉매의 특성으로 나타나도록 하는 복합산화물 촉매의 한 종류로서 스피넬 구조를 이루는 Mg- 및 Bn-페라이트를 촉매로 선정하여 K 첨가에 따른 물성을 분석하고 페라이트상에서 에틸벤젠의 탈수소반응에 대하여 연구하였다. 촉매의 특성분석에는 XRD, BET법, DTA, XPS, TEM, TPD 등의 분석기법을 사용하였다. 페라이트 촉매에 대한 K 첨가 효과를 검토하기 위하여 물성을 종합적으로 분석한 결과, K는 입자의 분산도를 향상시키는 구조적 조촉매로서의 역할과 함께 전자를 공급하는 조촉매로서 작용하였으며, K의 첨가량이 증가함에 따라 산점이 중화되어 그 세기가 약해지면서 산점의 농도는 증가하였다. 반응성을 연구한 결과 페라이트 촉매에 첨가된 K는 강한 산점을 중화시켜 탈수소 반응에 적합한 세기의 산점을 형성하여 스티렌의 선택도를 일정하게 유지하였다.

• 한국환경과학회지
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• 제20권11호
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• pp.1373-1382
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• 2011

This research had been conducted from May to October 2007, studying 110 residents of G, Y, H industrial area in Jun-nam province. It is designed to understand the difference in levels of indoor, outdoor and personal exposure to VOCs(benzene, toluene, Ethylbenzene) and a health risk assessment was conducted to see if there was any fatal cause from carcinogenic or non - carcinogenic elements from a case group and a control group in all areas as well as each different area. In the case of benzene in the air, the geometric levels for the case group are indoor, outdoor and personal exposure; a higher than for the control group. As a results of the Monte - Carlo study about benzene, it shows that the case group's carcinogenicity is higher than that of the control group and it also shows that, on the CTE, RME condition and Monte - Carlo analysis, all subjects are seen to exceed the carcinogenicity tolerance $10^{-6}$ of US EPA. In the case of toluene, ethylbenzene on the CTE, RME condition and Monte - Carlo analysis, these do not exceed the non - carcinogenic standard of 1, but toluene in RME condition for both groups' personal exposure and the indoor and personal exposure of ethylbenzene in Monte - Carlo show that these seem to exceed the standard.

• 한국산업보건학회지
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• 제20권3호
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• pp.192-202
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• 2010

This study aimed to suggest the severity of indoor air pollutants in screen gold arenas which were not sufficiently investigated in Korea up to now and to help users to enjoy golf in more pleasant indoor environment. The indoor environment survey was conducted with 21 screen gold arenas in Seoul from Oct. 28, 2008 to March 13, 2009. Indoor air quality was measured and analyzed in accordance with the Air Pollution Process Test Method specified bu NIOSH(2005). The screen golf arenas are mostly in the underground floors in this study, 4 on the ground floors(19.0%) and 17 in the underground floors(81.0%). In the air in screen golf arenas, the geometric mean of benzene, toluene, ethylbenzene and xylene were 2.92 ${\mu}g/m^3$, 70.34 ${\mu}g/m^3$, 14.00${\mu}g/m^3$ and 31.43 ${\mu}g/m^3$, respectively, which exceeded the exposure limites. Each arena exceeded the exposure limit for one pollutant each. However, styrene didn't exceed the limit as 8.09 ${\mu}g/m^3$. Furthermore, the geometric mean of formaldehyde was 63.11${\mu}g/m^3$ and 7 arenas exceeded the limit. The geometric mean of volatile organic compounds(VOCs) was 428.41${\mu}g/m^3$ and 10 arenas exceeded the limit. For the density distribution of pollutants by location, benzene, toluene, ethylbenzene, xylene, styrene and formaldehyde showed higher density distribution in underground spaces, for which the statistically significant difference was not found. However, PM10 showed the statistically significant difference (p<0.05). In accordance with the analysis on the correlation between the density of pollutants in the screen golf arenas, Pearson correlation coefficient between ethylbenzene and styrene was 0.980, very significant correlation(p<0.01). The correlation coefficients between the density of toluene, ethylbenzene, xylene and styrene and that of VOCs were 0.543, 0.434, 0.451 and 0.459, respectively, which demonstrated the statistically significant difference (p<0.05).

• 분석과학
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• 제24권2호
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• pp.119-126
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• 2011

국내 시중에 유통되어 음용되고 있는 먹는 샘물(생수) 30 종과 가정으로 공급되는 수돗물 9종 중의 벤젠, 톨루엔, 에틸벤젠, 자일렌을 고체상미량추출법을 사용하여 정량하였다. 정지상은 $100\;{\mu}m$ PDMS fiber를 이용하였고, 실험조건은 실온에서, 교반시간 1200 RPM G, 흡착시간 4 분, 탈착시간 1 분 이었다. 정량은 표준검량선법을 사용하였다. 평균검출한계는 벤젠 0.39 (${\pm}0.04$) ng/mL, 톨루엔 0.08 (${\pm}0.04$) ng/mL, 에틸벤젠 0.04 (${\pm}0.01$) ng/mL, o-자일렌 0.05 (${\pm}0.02$) ng/mL 이었다. 30 종의 먹는 샘물(생수)조사 결과 벤젠과 o-자일렌은 모든 시료에서 검출되지 않았으며, 톨루엔의 경우는 11 개의 시료, 에틸벤젠은 3 개의 시료에서 검출되었다. 검출된 물질의 각각의 농도범위는 $0.24({\pm}0.09)\sim2.95\;({\pm}0.08)\;ng/mL$, $0.08({\pm}0.06)\sim0.93({\pm}0.10)\;ng/mL$였다.

• 원예과학기술지
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• 제33권5호
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• pp.751-762
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• 2015

본 연구는 평면형 바이오필터를 설계하여 제작하고 이 바이오필터에 디펜바키아(Dieffenbachia amoena 'Marianne')의 식재 여부에 따라 환기 용량을 제어할 수 있는 토양 수분 안정화 정도를 측정하고 미세먼지, 휘발성 유기화합물 및 포름알데히드(HCHO)와 같은 실내공기 오염물질에 대한 바이오필터의 제거율을 비교하였다. 실험 결과 디펜바키아의 식재 여부에 관계없이 모두 일정한 상대습도, 온도 및 토양 수분 함량을 나타내었고 이 바이오필터에 식재한 디펜바키아도 정상적으로 생육하였다. 바이오필터에 의한 미세먼지 제거율을 보면, 미세먼지(PM10)와 초미세먼지(PM2.5)의 입자 수는 토양만 있는 경우 각각 30%와 2% 이상 제거되었고, 디펜바키아를 식재한 경우도 각각 40%와 4% 이상 제거되었다. 미세먼지(PM10) 무게에 따른 제거율은 토양만 있는 경우 4% 이상, 디펜바키아를 식재한 경우 20% 이상으로 나타났다. 토양만 채운 바이오필터는 xylene, ethylbenzene, toluene, total volatile organic compounds(T-VOCs)를 63% 이상 제거하였으나 benzene은 22% 이상, HCHO는 38% 이상을 제거하였다. 디펜바키아를 식재한 바이오필터는 xylene, ethylbenzene, toluene, T-VOCs를 72% 이상 제거하였고 benzene과 HCHO도 39% 이상 제거하였다. 따라서 식물과 바이오 필터를 결합한 시스템은 미세먼지의 제거보다 휘발성 유기 화합물의 제거에 대한 효과가 더 높은 것으로 나타났다. 본 연구에서 제작한 평면형 바이오필터는 실내 공기질 정화에 매우 효과가 있는 것으로 나타났으며, 식물과 바이오필터를 결합하였을 때 그 효과는 더욱 큰 것으로 확인하였다.

• 한국생명과학회:학술대회논문집
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• 한국생명과학회 2003년도 제39회 학술심포지움
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• pp.133-133
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• 2003

• 한국생명과학회:학술대회논문집
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• 한국생명과학회 2003년도 제39회 학술심포지움
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• pp.134-134
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• 2003

• KSBB Journal
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• 제13권5호
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• pp.469-476
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• 1998

Among 31 water-born microbial strains isolated from various sites in Korea, strain DJ-4 was selected as a test organism for toxicity measurements in that its growth was completely inhibited by the presence of 668.4 mg/L of chloroform and 297.5 mg/L of toluene in the liquid LB medium whereas others did not. It was observed that lag periods and specific growth rates of DJ-4 batch vial cultures were prolonged and decreased, respectively, by phenol, benzene, toluene, ethylbenzene, p-xylene, perchloroethylene, trichloroethylene, and chloroform at the concentrations between 3.6 and 417.8 mg/L. There changes were found to be linear with respect to the concentrations of the toxic compounds. From the first-order regression equations, 50% effective concentrations (EC50${\mu}$ for concentrations of toxic compounds causing 50% decrease of specific growth rates and EC50lag for 50% increase of length of lag periods) were calculated for each compounds. By comparing DJ-4 EC50${\mu}$ values with Daphnia LC50's from a literature for benzene, ethylbenzene, toluene, and trichloroethlyene, it was concluded that microbial specific growth could be a new, fast, and reliable parameter for toxicity tests.

• 한국환경보건학회지
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• 제32권4호
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• pp.275-281
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• 2006

Indoor air quality is the dominant contributor to total personal exposure because most people spend a majority of their time indoors. Especially exposure to indoor air can potentially pose a greater threat than exposure to ambient air when indoor environments have sources of contaminants. In this study, volatile organic compounds (VOCs) and formaldehyde (HCHO) within newly constructed apartment have been determined in 27 houses of apartment in Seoul from December 2004 to March 2005. The measured indoor air pollutants were HCHO, volatile organic compounds including benzene, toluene, styrene, xylene, ethylbenzene and sampled on the standard method of Ministry of Environment in Korea. The indoor levels for benzene, xylene, toluene, ethylbenzene, styrene, and HCHO have significant increase trend after 5 hours closing of windows and doors. Levels of measured air pollutants concentrations between living rooms and bedrooms have not shown significant difference. Spearman correlation coefficient among the measured air pollutants ranged from 0.303 to 0.946, indicating similar source in building materials.

• Asian Journal of Atmospheric Environment
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• 제8권4호
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• pp.192-201
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• 2014

A comprehensive profile of volatile organic compounds (VOCs) in public spaces is needed for interpreting indoor air measurements. Seasonal differences in profiles are critical for epidemiological study and risk assessment. The purposes of this study were to establish profiles for individual VOCs in 50 indoor public places in Korea and to determine seasonal variations in their concentrations. Air samples were taken during working hours. Seventy-two of the 91 targeted VOCs were identified using multiple standards. Six VOCs detected in all summer and winter samples were toluene, acetone, m,p-xylenes, ethylbenzene, benzene, and styrene. In summer, methyl ethyl ketone and 1-butanol were also found in all samples. In both seasons, the dominant indoor VOCs were toluene, m,p-xylenes, ethylbenzene, acetone, and isopropyl alcohol. Other chemicals associated with gasoline emissions were dominant in summer. Limonene was dominant only in winter due to the consumption of tangerines. The nine VOCs with the highest concentrations comprised 64.8% and 49.6% of the TVOC in summer and winter, respectively. Comparing two types of adsorbent tube, a single adsorbent tube with Tenax-TA had similar detection performance as a double adsorbent tube with Tenax and Carbotrap.