• Journal of Environmental Health Sciences
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• v.32 no.5 s.92
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• pp.418-423
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• 2006

이 사례연구는 누수가 있었던 고층 아파트의 공기중 진균 오염 실태를 조사하고, 이를 개선하기 위해 취해진 복원방법의 효과를 평가하기 위해 실시하였다. 공기중 진균은 주로 엔더슨 샘플러를 사용하여 측정하였다. 누수가 있었던 아파트의 복원 전 공기중 진균 농도는 매우 높았다(평균: $51,000\;cfu/m^{3}$, 기하평균: $40,163\;cfu/m^{3}$). 고농도의 오존처리와 오염된 벽체 철거 후 공기중 진균 농도는 상대적으로 매우 낮아졌으며(평균: $1,118\;cfu/m^{3}$, 기하평균: $899\;cfu/m^{3}$), 제거효율은 96.3%로 나타났다. 철거되지 않고 남아 있던 인근 벽체의 벽지를 제거하고 살진균제 처리를 실시한 결과, 공기중 진균 농도는 상대적으로 안전한 수준까지 낮아졌으며(평균: $95\;cfu/m^{3}$, 기하평균: $88\;cfu/m^{3}$), 제거효율은 99.7 %로, 나타났다. 결론적으로, 누수가 있었던 아파트의 공기중 진균 농도는 매우 높은 상태로 오염이 심한 상태이었으나, 본 연구에서 적용한 복원방법들은 공기중 진균 농도 저감에 있어서 매우 높은 효율을 나타냈다.

• Journal of Environmental Science International
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• v.18 no.12
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• pp.1325-1330
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• 2009

The fumigant 1,3-dichloropropene (1,3-D) was recently proposed as a direct replacement for methyl bromide ($CH_3Br$) in soil fumigation. This study was conducted to better understand behavior phase partitioning, diffusion and volatilization of 1,3-D as affected by isomer. The Henry's law constant(KH) of cis-1,3-D and trans-1,3-D was 0.058 and 0.037 at $20^{\circ}C$, respectively. $K_H$ of cis form of 1,3-D was higher than that of trans form of 1,3-D. To compare with volatilization of 1,3-D isomer, soil column [70 cm (length)${\times}$12 cm (i.d.)] included a shank injection at 30 cm with 300 kg $ha^{-1}$. Maximum cis-1,3-D and trans-1,3-D concentration reached 57 mg $L^{-1}$ and 39 mg $L^{-1}$ at 30 cm depth at 1h after application. Cumulatively, after 10 days, 51.8% and 43.57% of applied cis-1,3-D and trans-1,3-D was emitted via volatilization, respectively. The total losses of cis-1,3-D were significantly greater than that of trans-1,3-D. Finally, cis-1,3-D and trans-1,3-D, such as isomer are dominant of 1,3-D fates in soil.

• Proceedings of the KIEE Conference
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• 2002.07c
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• pp.1710-1713
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• 2002

Recently, the pulsed power system has been used to many applications. Such as remediation of environmental hazards, food sterilization, air pollution control E/P (Electrostatic Precipitator), DeNOx/DeSOx power system, ozone generator, high energy physics, and other power source applications. A pulse energy efficiency for load depends on the rising time, peak value. Pulse duration and impedance matching etc. The pulsed power system generally required for short pulse duration and high peak value was forced to consider its volume and economy. In this paper, we investigated operating characteristics of the CO2 laser using an inductively pulsed power system.

• Journal of Korean Society of Environmental Engineers
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• v.27 no.3
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• pp.240-246
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• 2005

Humic substances HS) from process waters at advanced water treatment plant consisted of GAC and Ozone/GAC processes were isolated and extracted by physicochemical fractionation methods to investigate their characteristics. They are characterized for their functionality, chemical composition, spectroscopic characteristics using FT-IR and $^1H$-NMR spectroscopy. Humic fraction gradually decreased from 36.3% to 24.2% from 0.45 to 0.30 mgC/L) through ozonation and carbon adsorption. The humic fraction was isolated into the phenolic and carboxylic groups using A-21 resin, and the concentration of phenolic groups gradually decreased from 38.4% to 23.5% (from 4.9 to $3.2\;{\mu}M/L$ as phenolic-OH) through ozonation and carbon adsorption. In the case of carboxylic groups, the concentration decreased from 61.6% to 43.3% (from 7.8 to $5.8\;{\mu}M/L$ as COOH) through the water treatment processes. On the other hand, concentrations of those roups decreased from 38.4% to 24.0% and 61.6% to 44.9% through carbon adsorption without ozonation, respectively. The structural changes of HS identified from FT-IR and $^1H$-NMR were consistent with the results from the isolation of functional groups in HS.