• Title/Summary/Keyword: Photodegration

Search Result 5, Processing Time 0.024 seconds

Photodegration Properties of Dye in $TiO_2$ Nanocomposite ($TiO_2$ 나노합성물에서 Dye의 광열화 특성)

  • Jeong, Jae-Hoon;Cho, Chong-Rae;Moon, Joung-Oh;Yang, Jong-Hyun;Moon, Byung-Kee;Son, Se-Mo;Chung, Su-Tae
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
    • /
    • 2001.11b
    • /
    • pp.517-520
    • /
    • 2001
  • The optical properties of $TiO_2$ thin films dispersed in epoxy film, which were prepared with bis-(4, 4'-P-toluenesulfonylacidic isoproplyidene) cycolhexadiol(BTSPC) and UVI 6990 in dry sol-gel process, were investigated. In the case of irradiating UV light on $TiO_2$ thin films, how many nanopartlcles of $TiO_2$ are dispersed in epoxy film was investigated by AFM. The absorption peak of the films was showed at 360nm. Squarylium dye was dispersed in $TiO_2$-epoxy film. Photodegration concerned with amount of dye and time of UV light irradiation was investigated. UV light irradiation on the film occurred dramatical photodegration.

  • PDF

Photodegration Properties of Dye in TiO$_2$ Nanocomposite (TiO$_2$ 나노합성물에서 Dye의 광열화 특성)

  • 정재훈;조종래;문정오;양종헌;문병기;손세모;정수태
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
    • /
    • 2001.11a
    • /
    • pp.517-520
    • /
    • 2001
  • The optical properties of TiO$_2$ thin films dispersed in epoxy film, which were prepared with bits-(4,4'-P-toluenesulfonylacidic isoproplyidene) cycolhexadiol(BTSPC) and UVI 6990 in dry sol-gel process, were investigated. In the case of irradiating UV light on TiO$_2$ thin films, how many nanoparticles of TiO$_2$ are dispersed in epoxy film was investigated by AFM. The absorption peak of the films was showed at 360nm. Squarylium dye was dispersed in TiO$_2$-epoxy film. Photodegration concerned with amount of dye and time of UV light irradiation was investigated. UV light irradiation on the film occurred dramatical photodegration.

  • PDF

A Study on the Correlation between Anchor Point and printing quality in a Uncoated Paper (비도피지에서 투묘효과와 인쇄품질의 관계에 관한 연구)

  • 김애연
    • Journal of the Korean Graphic Arts Communication Society
    • /
    • v.12 no.1
    • /
    • pp.117-132
    • /
    • 1994
  • New methodolgies for the syntheses of unsymmetrical squarylium(SQ) dyes for organic photoconductors(OPC) were developed and photostabilities for these dyes were dicucced. These dyes absorbed at 640-690nm and exhibit high molecular extinction coefficient about 10. photodegradation rate of these dyes is acceralated in the presence if singlet oxygen sensitizer. On the other hand, the photodegradation rate os retarded by adding effective singlet oxygen quencher, such as 2:1 metal dithiolate. It is suggested that the photodegration of unsymmetrical SQ dye may be due to a photo-oxidation involving singlet oxygen.

  • PDF

Synergistic Effect on the Photocatalytic Degradation of 2-Chlorophenol Using $TiO_2$Thin Films Doped with Some Transition Metals in Water

  • Jeong, O Jin
    • Bulletin of the Korean Chemical Society
    • /
    • v.22 no.11
    • /
    • pp.1183-1191
    • /
    • 2001
  • The metallorganic chemical vapor deposition (MOCVD) method has been used to prepare TiO2 thin films for the degradation of hazardous organic compounds, such as 2-chlorophenol (2-CP). The effect of supporting materials and metal doping on the photocatalytic activity of TiO2 thin films also has been studied. TiO2 thin films were coated onto various supporting materials, including stainless steel cloth(SS), quartz glass tube (QGT), and silica gel (SG). Transition metals, such as Pd(II), Pt(IV), Nd(III) and Fe(III), were doped onto TiO2 thin film. The results indicate that Nd(Ⅲ) doping improves the photodegradation of 2-CP. Among all supporting materials studied, SS(37 ${\mu}m)$ appears to be the best support. An optimal amount of doping material at 1.0 percent (w/w) of TiO2-substrate thin film gives the best photodegration of 2-CP.

Residual Characteristics of some Pesticides in/on Pepper Fruits and Leaves by Different Types, Growing and Processing Conditions (재배환경, 품종 및 가공 방법에 따른 고추와 고춧잎 중 농약의 잔류 특성)

  • Lee, Hee-Dong;You, Oh-Jong;Ihm, Yang-Bin;Kwon, Hye-Young;Jin, Yong-Duk;Kim, Jin-Bae;Kim, Yun-Han;Park, Seung-Soon;Oh, Kyeong-Seok;Ko, Sung-Lim;Kim, Tae-Hwa;Noh, Jae-Goan;Kyung, Kee-Sung
    • The Korean Journal of Pesticide Science
    • /
    • v.10 no.2
    • /
    • pp.99-106
    • /
    • 2006
  • Chlorothalonil and imidacloprid sprayed onto the green peppers were degraded more faster at outdoor than in greenhouse. These results were affected by dew and photodegration, considering no rain during the experimental period. Chlorothalonil, esfenvalerate and imidacloprid in green pepper, green twist pepper and sweet pepper did not show any residual pattern, because green peppers are one of the continuous harvesting crops and pesticides could not be sprayed homogeneously on them. When green peppers were pickled with soy sauce and green twist peppers were fried with vegetable oil, the amounts of pesticides such as alpha-cypermethrin, bifenthrin, chlorfenapyr, esfenvalerate and imidacloprid were diminished to the levels of about $30{\sim}71$ and $20{\sim}41%$, respectively. Esfenvalerate and imidacloprid could not be detected in 2 month-old hot pepper paste. The removal rates of pesticide residues in leaves of green peppers were about $22{\sim}37%$ by washing, about $74{\sim}95%$ by parboiling, and about $17{\sim}55%$ by drying after parboiling.