• Bulletin of the Korean Chemical Society
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• 제19권6호
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• pp.611-613
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• 1998

• 한국대기환경학회지
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• 제16권5호
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• pp.521-528
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• 2000

Photocatalyzed degradation of trace level trichloroethylene(TCE) and toluene in air was carried out over near UV illuminated titanium doxide(anatase) pellet in a flow reactor. The authors investigaed the effects of humidity and trace contaminant levels on the oxidation rates of toluene. Inlet concentrations of TCE and toluene were 10∼100ppm. TCE photooxidation was very rapid under what conditions, and almost 100% conversion was achieved for TCE(up to 70 ppm) as a single air contaminant. An important finding was that competitive adsorption between humidity and trace contaminants has a significant effect on the oxidation rate of what.

• Journal of Ginseng Research
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• 제14권3호
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• pp.385-390
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• 1990

To investigate the effect of ginseng extracts on the changes of flllidity and lysis of liposome reverse phase evaporation vesicle (REV) was employed as model membrane and methylene blue was used as photosensitizer. Fluoresence polarization (P vaule) that represented fluidity of liposome was increased by photooxidation. All of the ginseng saponin inhibited the increasing rate of P value; the order of effect was ginseng water extract>biol saponin>triol saponin>crude saponin. In trapped G-6-P% measurement for lysis of liposome, ginseng water extract and crude saponin promoted the lysis of liposome. Therefore, we thought that ginseng extracts acted as both antioxidant and detergent.

• 청정기술
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• 제4권2호
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• pp.11-22
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• 1998

광증감제로서 과황산 이온, 황산 이온, 질산 이온, 아질산 이온 및 염소 이온을 이용한 반응조건하에서 수용액중 벤젠의 광증감 산화반응을 조사하였다. 과황산 이온이 가장 효과적인 광증감제로 나타난 반면, 황산 이온 및 아질산이온은 벤젠의 광증감 산화반응에 증감역할을 수행하지 못하였다. 아질산 이온은 다른 이온과 공존할 때 생성된 ${\cdot}OH$라디칼을 소멸시켜 벤젠의 광증감 산화반응을 저해하는 것으로 나타났다.

• Journal of Photoscience
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• 제9권3호
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• pp.57-63
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• 2002

A homopolymer containing anthracene groups, poly[6-(9-anthryloxy)hexyl methacrylate] (PAn) was prepared and the effect of oxygen on its photochemical reaction was studied by UV and IR absorption spectroscopy in order to understand its photochemical behavior. Photochemical reaction of the PAn in THF solution under an atmosphere of air resulted in the formation of endoperoxide at the beginning stage of reaction followed by photodimerization reaction after all the oxygen was consumed, whereas photodimerization and endoperoxide formation took place concomitantly in the film state. The photoreversible reaction of the anthracene photodimer groups in the polymer by photolysis with 254 nm UV light was not efficient. The IR absorption spectral changes of the PAn film upon irradiation indicate that various photooxidation products were produced in the atmosphere of air.

• 대한화학회지
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• 제39권2호
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• pp.136-137
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• 1995

• 한국환경과학회:학술대회논문집
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• 한국환경과학회 2017년도 정기학술대회 발표논문집
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• pp.88-88
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• 2017

• Journal of Ginseng Research
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• 제14권1호
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• pp.57-62
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• 1990

In order to Investigate the mechanism of the leaf-burning disease of ginseng (Panax ginseng C.A. Meyer), studies on the generation of singlet oxygen (1O2) and the photooxidation of the pigments were carried out in comparison with the ones of soybean (G1ycine max L). The studies were mainly focalized on the effects of light intensity, light intensity, inhibitor and electron donor/acceptor of the Photosynthetic electron transport system. When we measured the amounts of 1O2 generated in the thylakoids of ginseng and soybean by the irradiation of light (300 w/m2) as a function its time. It was identified that a higher amount of 1O2 was formed in the ginseng thylakoid than the case of soybean. A generation ratio of lO2 between ginseng and soybean sltbstantially identical in the range of light intensities 50∼150w/m2 However much higher amount of 1O2 was generated in ginseng by irradiation of strong intensity of light (200 500w/m2). Wave length dependency on the generation of 1O2 and the pigment photooxidation was observed on ginseng thylakoids; red light (600-700 nm) gave a maximum effect in the contrast with blur green light (400-60 nm). When the ginseng thylalioid was treated with the electron donor (Mn2+) and acceptors (DCPIP, FeCy) of the photosynthetic electron transport system. a drastic inhibition of 1O2 generation was observed. However, treatment with its inhibitors (DCMU, KCW) activated 1O2 generation. An interesting fact that an electron donor or acceptor of the photosystem II(P680) Inhibited 1O2 generation, suggests an intimate relationship between 1O2 generation and photosystem II.

• 한국식품영양과학회지
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• 제33권2호
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• pp.291-298
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• 2004

김치에는 여러 가지 항산화 물질들이 많이 함유되어 있으므로 김치의 섭취는 생체조직의 노화억제 효과가 있을 것으로 기대된다. 본 연구에서 배추김치, 갓김치, 부추김치를 동결건조하여 항산화물질의 함량을 측정한 결과 갓김치와 부추김치의 클로로필 함량이 가장 높았고 $\beta$-카로텐과 ascorbic acid 함량은 갓김치에서 가장 높았다. Hairless mouse에게 10% 동결건조 김치식이를 공급하여 20주간 사육한 후 간에서 활성산소종의 생성량을 측정한 결과 superoxide anion과hydroxyl radical 함량은 유의적인 차이가 없었고 hydrogen peroxide 함량은 갓김치군과 부추김치군에서 유의적으로 낮게 나타나 이들 김치가 활성산소를 소거하는데 효과가 있는 것으로 나타났다. 간 균질액에서 지질과산화물을 측정한 결과 대조군에 비해 김치섭취군에서 지질과산화가 낮게 나타났으며, 특히 갓김치 와 부추김 치군의 효과가 우수하였다. 피부에서 지질과산화물 함량은 김치섭취군들이 대조군보다 낮게 나타났으며, 부추김치가 유의적으로 지질과산화를 억제하였다. 김치섭취가 광산화에 미치는 영향을 규명하기 위해 간 및 피부조직에 자외선을 조사한 후 조직산화 정도를 측정한 결과 간과 피부의 지질과산화물 함량은 갓김치군과 배추김치군에서 대조군보다 낮아졌으나 부추김치군에서는 높게 나타났다. 즉, 자외선 조사 후 갓김치군과 배추김치군은 대조군보다 광산화가 억제되었으나 부추김치군에서는 산화가 촉진되었다.

• 한국대기환경학회지
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• 제33권2호
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• pp.87-96
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• 2017

In this study, 4 gases containing typical chlorinated volatile organic compounds (VOCs) were treated by ultraviolet (UV) irradiation. The typical chlorinated VOCs are dichloromethane (DCM), trichloromethane (TCM), carbon tetrachloride (CTC) and trichloroethylene (TCE). The removal efficiency (RE) and the products of chlorinated VOCs by UV irradiation are investigated. At this time, 2 types of background gas (air and nitrogen) were used to figure out the RE by photooxidation and photolysis. The specification of UV-lamp used in this study was low-pressure mercury lamp emitting wavelength of 185~254 nm. The experimental conditions were set as initial VOC concentration of $180{\pm}10ppm$, empty bed retention time (EBRT) of 53 s, temperature of $23{\pm}2^{\circ}C$ and relative humidity of $65{\pm}5%$. In the photolysis condition with nitrogen ($N_2$) as background gas, the averaged RE of the 4 types of chlorinated VOCs was about 24% higher than that with photooxidation; and the REs of VOCs except CTC were confirmed as >99%. The composition of off-gases after UV photooxidation in air was investigated and several intermediates from DCM, TCM and TCE were detected by GC/MS. Among them, phosgene which is a toxics was detected as an intermediate of TCM. In addition, the concentration of carbon dioxide ($CO_2$) in the off-gases was measured to calculate the mineralization rate (MR). With the photooxidation, TCE showed the highest RE (>99%) while MR was the lowest (17%); and the MR of DCM was the highest (86%). In addition, particulate matters (PM) in the off-gases was also detected and high concentrated $PM_{10}$ ($21,580{\mu}g{\cdot}m^{-3}$) and $PM_{2.5}$ ($6,346{\mu}g{\cdot}m^{-3}$) were detected in TCE off-gas. More than 99% of the chlorinated VOCs could be removed using UV254-185 nm lamp, while it is necessary to conduct further studies on the production and treatment of secondary pollutants.