• Proceedings of the Korean Society of Crop Science Conference
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• 2003.10a
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• pp.128-129
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• 2003

• Proceedings of the Korean Environmental Sciences Society Conference
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• 2006.11a
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• pp.133-135
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• 2006

산림 canopy 내 외에서 대기환경은 광화학적 반응 속도나 기상 요인들의 영향에 의해 다소 달라질 수 있기 때문에 이에 대한 연구로서 monoterpene의 대표 성분인 ${\alpha}-pinene$ 및 ${\beta}-pinene$를 이용하여 산림 고도별 분포 특성을 조사하였다. 침엽수림과 활엽수림 모두에서 ${\alpha}-pinene$ 및 ${\beta}-pinene$ 성분의 높이별 농도는 canopy영역보다 canopy아래 산림 내부에서 상대적으로 높게 측정되었으며, 고도별로 농도 차이가 있지만 고도에 관계없이 ${\alpha}-pinene$이 ${\beta}-pinene$보다 $1.3{\sim}1.5$배정도 농도가 높았다.

• Transactions of the Korean hydrogen and new energy society
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• v.4 no.2
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• pp.5-15
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• 1993

Hydrogen production in visible light with the following semiconductor systems, $CdS-WO_3$, $CdS-TiO_2$, have been investigated in the presence of redox catalyst (Pt, $RuO_2$). MeOH, EtOH, isopropanol, sulfide/sulfite mixture, lactic acid were used as sacrifical reagents. The optimal condition for $H_2$ evolution was found to be in qgueous lactic acid media for $CdS-WO_3/RuO_2$. The photochemical efficiency for this system was 1.05 % and the $H_2$ evolution rate was 26.5ml/min. at $6.07{\times}10^{-5}$ einstein/sec photon rate

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2000.04a
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• pp.265-266
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• 2000

휘발성 유기화합물(VOCs)은 새로운 유형의 스모그의 광화학반응 촉진제로서의 작용 및 환경학적 문제점들을 제기하고 있으며 공단 주변의 악취발생 및 환경 오염사건등을 유발시키고 있다. 이러한 휘발성 유기화합물을 적절하게 제어할 수 있는 방지대책의 여러 가지 방법들이 국내외적으로 활발히 연구되어지고 있다. 산업현장에서 이들 휘발성유기화합물의 배출을 제어하기 위한 기술 보유 및 개발에 있어서는 아직까지 미비한 단계에 있으며 보유기술의 현장적용의 측면에서 휘발성유기화합물이 지니고 있는 특이한 물리적 성질 등에 의해 많은 어려움을 가진다. (중략)

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2001.11a
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• pp.289-290
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• 2001

비메탄계 휘발성 유기화합물(Non-Methane Volatile Organic Compounds; NMVOCs)은 많은 부분이 용제를 사용하는 공정에서 발생되어 광화학적 산화물 형성 등의 대기질 악화를 초래시키는 것으로 알려져 있다. 반면에 메탄가스는 지구온난화의 원인물질로 환경에 많은 영향을 미치는 것으로 알려져 있고, 국내의 쓰레기 매립지에서 발생되는 양은 년간 112만톤으로 추정되어 메탄의 자원화나 처리에 대한 연구가 매우 필요한 실정이다. (중략)

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2002.04a
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• pp.95-96
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• 2002

과산화수소(hydrogen peroxide, $H_2O$$_2$)는 광화학적 이차 생성물이며, 대기의 산화상태를 알려주는 지시자의 역할을 한다 과산화수소는 HO$_2$ 라디칼의 self-reaction 으로 생성된다. HO$_2$＋HO$_2$＋ M$\longrightarrow$$H_2O$$_2$＋M, OH나 HO$_2$ 라디칼은 NOx나 hydrocarbon 과 같은 대표적인 오존 전구물질들을 산화시킨다. 대기 내수명이 불과 1초 이내인 OH나 HO$_2$ 라디칼을 직접 측정하기란 어려우며 수명이 1-2 일 정도인 $H_2O$$_2$를 측정하므로써 이들 라디칼의 대기 내 농도를 예측 할 수 있다. (중략)

• Journal of the Korean Society for Precision Engineering
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• v.22 no.7 s.172
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• pp.38-46
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• 2005

In laser machining such as drilling with $CO_2$ or Nd:YAG laser, and etching or ablation with Excimer laser, one of the most important parameters affecting the machining is known to be beam characteristics. In this paper a numerical study is performed to investigate the effects of beam parameters, especially in the process of excimer laser ablation of polymers. Results of different beam conditions reveal that if the ablated depth is small compared to beam size the simple photochemical etching model is suitable to predict the etched shape, and that the importance of precise alignment becomes large as beam quality factor becomes larger.

• Journal of the Korean Chemical Society
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• v.20 no.6
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• pp.520-524
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• 1976

A model compound for pyrimidine bases, N-methyllutidone, was irradiated with benzophenone in acetonitrile at 313 nm. Three of the four photoproducts were isolated by column chromatography and characterized. N-(Benzhydrylmethyl) lutidone, lutidone, and N-(4-benzoylbenzyl) lutidone were formed with quantum yields of $5.07{\times}10^{-3},\;1.84{\times}10^{-3},\;and\;1.43{\times}10^{-3}$ respectively.

• Journal of Korean Society for Atmospheric Environment
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• v.22 no.3
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• pp.361-371
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• 2006

This study examines ozone episodes occurred during the intensive sampling periods (Jun. 1-30, 2004) in the air of Seoul metropolitan area. During that period, there were 8 events (or days) in which 1 hr averaged ozone concentrations were greater than 100 ppbv. The photochemical analysis of ozone chemistry (i.e., budget and formation and destruction strengths of ozone) was carried out using a photochemical box model. Peaks in diurnal ozone variations during ozone episode periods occurred were concurrent with the sudden change of the slope of $NO_{2}/NO$ ratio, suggesting significant correlation with photochemical reactivity. In addition, the ozone peaks were concurrent with high concentrations of ozone precursors, peroxy radicals of $HO_{2},\;CH_{3}O_{2},\;and\;RO_{2}$. High ozone levels during the ozone episodes are likely to be affected by ozone destruction rate.

• Journal of the Korean Chemical Society
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• v.20 no.4
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• pp.290-294
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• 1976

Radiation-induced cis-trans isomerization of ${\beta}$-styrylnaphthalene is studied by determination of G values and the radiostationary states. The results are compared with data obtained in direct and sensitized photoisomerization of the compound. Both the excited singlet and triplet states are involved in the isomerization of ${\beta}$-styrylnaphthalene in the radiolysis of benzene solution.