• Bulletin of the Korean Chemical Society
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• v.27 no.9
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• pp.1305-1309
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• 2006

Photolysis of (2-hydroxymethylphenyl)pentamethyldisilane 1 in methanol provides a novel intramolecular photoproduct 4 via silene intermediate 2 but the photoreaction of (2-acetoxymethyl- or allyloxymethylphenyl) pentamethyldisilanes 5 or 10 in methanol affords unexpected photoproducts 8 or 13, respectively, instead of expected intramolecular photoproducts.

• Journal of the Korean Chemical Society
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• v.36 no.5
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• pp.784-787
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• 1992

• YAKHAK HOEJI
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• v.25 no.3
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• pp.83-87
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• 1981

Reaction of 3-chloroindolenine with acetic acid gives oxindole and acetoxyindole. Similar treatment of 3-bromoindolenine affords 6-bromoindole. Reaction of 3-chloro-and 3-bromoindolenine with methanolic sodium hydroxide gives 3-methoxyindolenine, 2-methoxyindolenine and oxindole. Thermal reaction of 3-bromoindolenine in 1, 1', 2, 2'-tetrachloroethane gives 6-bromoindole but no reaction is occurred in 3-chloroindolenine. Photolysis of 3-chloroindolenine gives indole, 4-, 5- and 7-chloroindole.

• Bulletin of the Korean Chemical Society
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• v.19 no.6
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• pp.686-689
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• 1998

Irradiation of 1-(o-allyloxyphenyl)-2-pentamethyldisilanylethyne (2) in methanol yields two 1 : 1 photoaddition products (3 and 4) via silacyclopropene intermediate. Photolysis of (2) with acetone in deaerated methylene chloride yields site specific and regioselective 1: 1 adducts (7 and 8) via silacyclopropene and 1-sila-1,2-propadiene intermediate, respectively.

• Bulletin of the Korean Chemical Society
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• v.15 no.8
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• pp.607-608
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• 1994

• Journal of the Korean Chemical Society
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• v.11 no.3
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• pp.85-88
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• 1967

The main object of this experiment is to provide a systematic approach to the reaction mechanism in the photolysis of 5-phenyl-1,2,3,4-tetrazole during which the formation of C-phenyl-nitrile-imine of 1.3-dipole was expected. So the occurrence of 1,3-dipole-addition was examined but not observed despite the formation of nitrile-imine. 3,6-diphenyl-1,2,4,5-tetrazine (IV); 3,6-diphenyl-1,4-dihydro-1,2,4,5-tetrazine (III); 3,5-diphenyl-1,2,4-triazole; 4-amino-3,5-diphenyl-1,2,4-triazole; benzonitrile; ammonia and nitrogen were isolated as final products of this reaction.

• Journal of Korean Society for Atmospheric Environment
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• v.19 no.4
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• pp.437-449
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• 2003

A multi-functional indoor smog chamber was designed and evaluated to investigate photochemical or water vapor reaction mechanisms of air pollutants. Various smog chamber experiments could be conducted using ambient air or purified air in this smog chamber. The smog chamber consisted of a housing, a Teflon bag, blacklights, injection ports, sampling ports, and utility facilities. The characteristics of light source, the wall losses of air pollutants, and the quality of purified air were experimentally investigated. The maximum NO$_2$ photolysis rate was 1.10 min$^{-1}$ . In a 2.5-m$^3$ Teflon bag, the wall losses of ambient $O_3$, NO, and NO$_2$ were 1.2~2.4$\times$10$^{-3}$ min$^{-1}$ , 0.7~2.0$\times$10$^{-3}$ min$^{-1}$ , and 0.4~2.0$\times$10$^{-3}$ min$^{-1}$ , respectively. The wall loss of ambient particles ranging 0.05 to 0.2 ${\mu}{\textrm}{m}$ was 1.8~5.4$\times$10$^{-3}$ min$^{-1}$ , which was slightly higher than those of ambient gaseous species. The purified air supply system provided high quality of air with NO$_{x}$ < 1 ppb, and total hydrocarbons < 5 ppb.b.

• Journal of the Korean Chemical Society
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• v.34 no.3
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• pp.255-259
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• 1990

The nitrogen-laser flash photolysis apparatus has been set up to detect directly the transient produced from the excited Benoxaprofen (BXP). The function of the instrument has been tested by using anthracene as a standard sample. The laser photoexcitation of BXP in ethanol has been carried out under a constant stream of $N_2$ gas and a transient absorption spectrurn has been recorded over the 400-600 nm. The effects of oxygen and ${\beta}-carotene$ on the transient spectrum reveal that thee maximum transient absorption at 415 nm is attributed to the triplet state of BXP and the triplet energy of BXP is above 22 Kcal/mole. In addition to the triplet state, another transient species has been observed to be produced, which is probably a radical form of BXP. The photosensitization mechanism of BXP is discussed based on these results.

• Bulletin of the Korean Chemical Society
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• v.30 no.8
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• pp.1798-1804
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• 2009

In this study, we have studied on improved performance of carbon nanotubes/titanium (CNT/TiO2) structure electrode for methylene blue (MB). The composite electrodes consisting of CNTs and a titanium oxide matrix with phenol resin binder was fabricated with a mixture method. The chemical and morphological structure of CNT/Ti$O_2$ composites were characterized by means of BET surface area, X-ray diffraction (XRD), scanning electron microscopy (SEM), UV-Vis absorption technique, Raman spectroscopy and energy dispersive X-ray (EDX). The electrode showed a remarkably enhanced performance for MB oxidation under UV illumination with or without electro-chemical reaction (ECR). Such a remarkably improved performance of the CNT/Ti$O_2$ structure electrode might be due to the enhanced MB oxidation by electro- and photo-generated electrons and holes in the CNTs and Ti$O_2$ under UV illumination with or without ECR.

• Biomolecules & Therapeutics
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• v.2 no.2
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• pp.136-140
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• 1994

To prove the hypothesis that NO- and N $O_2$-carrying molecules potentiate photorelaxation by generating NO, investigation was carried out using isolated rabbit and human corpus cavernosum. Corporal smooth muscle, in the presence or absence of endothelium, relaxed only slightly upon ultraviolet light (366 nm) irradiation. But, NO-and/or N $O_2$-containing compounds such as streptozotocin and $N^{G}$-nitro-L-arginine methyl ester significantly (p<0.01) enhanced photorelaxation in this tissue. In addition, $N^{G}$-nitro-D-arginine methyl ester, known to lack inhibitory action on NO synthase, showed concentration-dependent potentiation of the photorelaxation. Oxygen radical generating system via copper＋ascorbic acid and guanylate cyclase inhibitor, methylene blue, significantly (p<0.05) inhibited the streptozotocin-potentiated photorelaxation. Nitrite was accumulated by photolysis of streptozotocin, $N^{G}$-nitro-L-arginine methyl ester and $N^{G}$-nitro-D-arginine methyl ester, in a concentration and exposure time dependent manner. These observations indicate that NO is a potent relaxant of rabbit and human corpus cavernosum and further support the hypothesis that NO is released by photolysis from NO- and N $O_2$-carrying molecules.lecules.