• 제목/요약/키워드: photochemical

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PHOTOCHEMICAL REACTION OF POLYHEDRAL BORON COMPOUND WITH DIBROMOCARBENE

  • Sung, Dae-Dong;Chang, Jeong-Ah;Kang, Dong-Hyo
    • Journal of Photoscience
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    • v.3 no.1
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    • pp.39-42
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    • 1996
  • The photochemical reaction of phenyl(tribromomethyl)mercury with nido-decaborane gives a new boron cluster expanded compound. The two borons at the 6- and 9- positions in decaborane behave as electrophilic centers for the reaction with dibromocarbene. The first step in this reaction is the addition of two molar equivalents of dibromocarbene which is produced from phenyl(tribromomethyl)mercury to nido-decaborane. In the second step the unstable intermediate generates the product, 1,2-$Br_2C_2B_{10}H_{10}$ through loss of H$_2$.

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A study on the characteristics of ozone generation using photochemical reaction lamp (광화학 램프를 이용한 오존발생 특성 연구)

  • Woo, Sung-Hun;Lee, Sang-Keun;Lee, Kwang-Sik
    • Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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    • 2004.11a
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    • pp.321-323
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    • 2004
  • In this paper, We have designed and manufactured a photochemical reaction lamp type ozonizer system which was performed a role of preservation of oriental herbal medicine. This paper describes preliminary discussions on the characteristics of ozone concentration and discharge parameters according to number of turn-on lamp.

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Synchrotron Radiation Induced Photochemical Reactions for Semiconductor Processes

  • Rhee, Shi-Woo
    • Journal of the Korean Vacuum Society
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    • v.3 no.2
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    • pp.147-157
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    • 1994
  • Valence or core electron excitations induced by Synchrotron radiation (SR) irradiation and ensuing chemical reactions can be applied for semiconductor processes i, e, deposition etching and modifications of thin film materials. Unique selectivity can be achieved by this photochemical reactions in deposition and etching. Some materials can be ecvaporated by SR irradiation which can be utilized for low temperature surface cleaning of thin films. Also SR irradiation significantly lowers the reaction temperature and photon activated surface reactions can be utilized for direct writing or projection lithography of electronic materials. This technique is especially effective in making nanoscale feature size with abrupt and well defined interfaces for next generation electronic devices.

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Numerical Simulation of NOx Concentration in Gwangyang Bay, Korea (광양만권 질소산화물(NOx)의 수치모의)

  • 이상득;유지영
    • Journal of Environmental Science International
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    • v.11 no.9
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    • pp.897-905
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    • 2002
  • A three-dimensional photochemical air pollution model considered advection, dispersion, photochemical reactions, and precipitation processes was developed. The calculated results of meteorological observation clearly exhibited geographical effects of Gwangyang Bay, in which land and sea breezes, mount-valley winds and local circular winds occurred. The observed results of daytime NOx concentrations were slightly higher than the calculated NOx concentrations in Yosu industrial complex, Gwangyang iron mill, and container yard. Eventually, the calculated NOx results generally agreed well with the observed ones.

Comparing Meteorological Fields and Their Impacts on Carbon Bond Mechanism-IV Modeling

  • Lee, Hwa-Woon;Lee, Soon-Hwan;Kim, Heon-Sook
    • Proceedings of the Korea Air Pollution Research Association Conference
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    • 2003.11a
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    • pp.449-450
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    • 2003
  • Performance of photochemical models and their response to emission controls are heavily dependent on the inputs to the model. Two key inputs to these models are accurate meteorological and emissions data. But they can contain significant errors which contribute to uncertainties in photochemical simulation (Kumar and Russell, 1996; Sistla et al., 1996; Pielke and Uliase, 1998; Barna and Lamb, 2000; Nelson L. Seaman, 2000: Hogrefe et al., 2001; Biswas et al., 2001).(omitted)

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Effect of an Extra Chloro Substituent on Photochemistry of o-Alkylphenacyl Chloride

  • Park, Bong-Ser;Jeong, Seong-Jin
    • Bulletin of the Korean Chemical Society
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    • v.30 no.12
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    • pp.3053-3056
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    • 2009
  • The title compound, ${\alpha},{\alpha}$-dichloro-o-methylacetophenone, was prepared and its photochemical behavior was investigated. Addition of an extra chlorine at alpha position to the carbonyl showed many different features from photochemical reactivities of mono chloro analogue, 2,5-dimethylphenacyl chloride. In benzene, a rearrangement product with a formal 1,5-Cl shift and a reduction product were formed beside indanone. In methanol, solvolysis and cyclization of a common dienol intermediate occurred at comparable reaction rates.

The Effect of External Noise on Dynamic Behaviors of the $Schl\ddot{o}gl$ Model with the First Order Transition fora Photochemical Reaction

  • 김경란;Lee, Dong J.;신국조
    • Bulletin of the Korean Chemical Society
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    • v.16 no.11
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    • pp.1113-1118
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    • 1995
  • The Schlo'gl model with the first order transition for a photochemical reaction is considered to study the dynamic behaviors in the neighborhood of the Gaussian white noise by obtaining the explicit results of the time-dependent variance and time correlation function with the aid of approximate methods based on the stationary properties of the system. Then, we discuss the effect of external noise strength on the stability of the model at steady states in detail.

The Effect of External Noise on Dynamic Behaviors of the Schlogl Model with the Second Order Transition for a Photochemical Reaction

  • 김경란;Lee, Dong J.;신국조
    • Bulletin of the Korean Chemical Society
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    • v.16 no.11
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    • pp.1119-1121
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    • 1995
  • The method for the Schlo"gl model with the first order transition is extended to the Scho;gl model with the second order transition for a photochemical reaction. We obtain the explicit results of the time-dependent average and the time correlation function at the unstable steady state of the model in the neighborhood of the Gaussian white noise and then discuss the effect of noise on the dynamic properties.