• 제목/요약/키워드: Photolysis

검색결과 235건 처리시간 0.027초

반응속도상수와 오염물질의 초기 농도가 오존농도 예측에 미치는 영향 (Effect of the Photolysis rate and Initial concentration for the Pollutants on modelled Ozone concentration)

  • 이화운;김유근;원경미;김희정
    • 한국대기환경학회:학술대회논문집
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    • 한국대기환경학회 1999년도 추계학술대회 논문집
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    • pp.422-423
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    • 1999
  • 최근 저유황 연료유의 공급과 청정연료의 사용 등으로 인해 1차 오염물질은 점차 줄어드는 추세에 있는 반면, 늘어나는 자동차와 급속한 산업화로 산업시설에서 배출되는 질소산화물과 탄화수소류, 휘발성 유기화합물(VOC) 등이 복잡한 광화학 반응을 통해 2차 오염물질을 생성함으로 대기오염의 문제가 심각하다.(중략)

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Photochemistry of $\alpha$-(o-Alkylphenyl)indanones

  • Jeong, Soo-Young;Park, Bong-Ser
    • Journal of Photoscience
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    • 제7권1호
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    • pp.35-37
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    • 2000
  • Photolysis of $\alpha$-(o-alkylphenyl) indanones resulted in $\alpha$-cleavage followed by disproportionation to form E-and Z- ortho-formyl stilbenes. No evidences of hydrogen abstraction reactions were collected from these indanones. The minimum rate constant of $\alpha$-cleavage in the $\alpha$-(o-alkylphenyl) indanones was estimated to be 5.5$\times$10$^{10}$ s$^{-1}$ .

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TCE와 B.T.X. 처리에 관한 자외선 광산화 및 광촉매 산화 공정의 비교 실험 (A comparison Study on UV Photolysis and Photocatalytic-oxidation of TCE and B.T.X. in Air)

  • 정창훈;서정민;김찬훈;최금찬
    • 한국대기환경학회:학술대회논문집
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    • 한국대기환경학회 2000년도 추계학술대회 논문집
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    • pp.255-256
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    • 2000
  • 휘발성 유기화합물(Volatile Organic Compounds : VOCs)은 각종 산업체에서 많이 사용되고 있는 용매와 화학 및 제약공장 플라스틱의 건조공정에서 배출되는 유기가스 등까지 매우 다양하며, 저비점 액체연료, 파라핀, 올레핀, 방향족 화합물등 우리 생활주변에서 흔하게 사용되는 탄화수소류들이 거의 VOCs이다. 이러한 VOCs를 제어하기 위하여 폭넓은 제어기술의 연구 및 개발이 진행되고 있다. (중략)

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2001년 서울시 오존 집중 측정 시기 HCHO의 측정 (Measurements of HCHO during ozone intensive study in Seoul, 2001)

  • 홍상범;김규수;이재훈
    • 한국대기환경학회:학술대회논문집
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    • 한국대기환경학회 2002년도 춘계학술대회 논문집
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    • pp.319-320
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    • 2002
  • 포름알데하이드(HCHO)는 보건학적인 영향과 광화학 스모그 형성과정의 중요한 역할로 인해 많은 연구의 대상이 되어왔다. 포름알데하이드(HCHO)의 도심지 대기 환경에서 가장 중요한 인위적인 발생원은 산업활동 및 자동차의 배기가스이며 식물의 연소과정(biomass burning)에서도 방출되는 것으로 알려져 있다. 또한 대기환경에 존재하는 휘발성 유기화합물들과 OHㆍ과의 광 화학적 산화과정을 통하여 2차적으로 형성된다. 한편, 주요 소멸과정으로는 광분해(photolysis) 과정과 OHㆍ과의 반응이다. (중략)

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PHOTOINDUCED ELECTRON TRANSFER REACTIONS OF 1,4-DIPHENYL-1,3-BUTADIYNE

  • Kim, Bang-Duk;Shim, Sang-Chul
    • Journal of Photoscience
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    • 제5권1호
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    • pp.23-26
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    • 1998
  • Irradiation of diphenylbutadiyne (DPB) in methanol with 9,10-dicyanoanthracene (DCA) yields four methanol adducts, two more than the products obtained in the absence of DCA. Laser flash photolysis studies indicate the reaction to proceed through a photoinduced electron transfer mechanism involving DPB cation radical and DCA anion radical.

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Photodecomposition Mechanism of 2-Methoxy-1,2-diphenyl Diazoethane

  • 성대동;임귀택;김민식;박동규
    • Bulletin of the Korean Chemical Society
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    • 제16권1호
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    • pp.47-52
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    • 1995
  • The mechanism of the photodecomposition of 2-methoxy-1,2-diphenyl diazoethane has been investigated in methanol and isoprene using time-resolved laser flash photolysis techniques. The reaction of triplet carbene which is generated from 2-methoxy-1,2-diphenyl diazoethane with methanol is believed to proceed via thermal excitation to the singlet state. The activation energy and enthalpy are consistent with a mechanism involving thermal equilibrium between the triplet and singlet state followed by the reaction of the singlet with methanol to give ether.

Photolysis of Aqueous Ammonia in the Absence and the Presence of O₂

  • 박형련;김희정;성아영
    • Bulletin of the Korean Chemical Society
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    • 제17권9호
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    • pp.798-802
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    • 1996
  • The photochemical decomposition of aqueous ammonia in the absence (saturated with argon) and the presence of O2 (saturated with air or oxygen) has been investigated using 184.9 nm UV light. The decomposition of ammonia depended on the concentration of oxygen in the solution. With increasing the concentration of oxygen, the decomposition of ammonia diminishes. Hydrazine is found the major product from the irradiation. In the presence of oxygen, hydrogenperoxide was also produced. The product yields depended also on the concentration of oxygen in the solution. The initial quantum yield of the products and of the ammonia decomposed were determined. Probable reaction mechanisms for the reaction were presented from the products analysis.

The Double Photodissociation of Geminal, Dichloride

  • Platz, M. S.;Lee, Woo-Bung
    • Bulletin of the Korean Chemical Society
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    • 제10권4호
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    • pp.374-377
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    • 1989
  • Photolysis of dichlorodiphenylmethane in glassy 2-MeTHF at 77K results in the formation of diphenylcarbene and the diphenylchloromethyl radical, which were detected by their flourescence emission and excitation spectra. The relative yield of the carbene to radical is shown to vary dramatically as a function of irradiation time. The photolability of the radical is also demonstated. These results were interpreted in terms of a two step mechanism, where the diphenylchloromethyl radical is an intermediate in the formation of diphenylcarbene.