• 한국환경농학회지
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• 제21권3호
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• pp.172-177
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• 2002

살충제 carbofuran의 수중 광분해 실험을 미국 EPA 및 OECD 방법으로 수행하였다. Carbofuran은 자연광을 흡수하지 않는 화합물이지만, 야외에서 증류수로 수행한 광분해시험 결과 반감기가 9.7일, SUNTEST에서 3.4일, SUNTEST의 UV하에서 1시간으로 신속한 광분해가 일어남을 확인하였다. 특히 논물에서는 SUNTEST에서의 반감기가 14시간으로 증류수 보다 약 6배 가속화되었으며, 살균한 논물보다는 비살균 논물에서의 광분해가 다소 빠르게 일어났다. 이와 같은 결과로 볼 때 carbofuran의 경우 수도작 상황에서 sensitizer 등에 의한 간접 광분해의 가능성이 있음을 확인하였다.

• 대한화장품학회지
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• 제43권4호
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• pp.381-390
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• 2017

본 연구에서는 국내 유통 중인 자외선 차단 기능성화장품 총 100건을 대상으로 살균보존제 16종과 자외선차단성분 18종의 사용실태를 조사하였다. 그 결과, 검출률이 가장 높은 살균보존제 성분 5가지는 페녹시에탄올(61건), 안식향산(19건), 메틸파라벤(11건), 벤질알콜(8건), 프로필파라벤(7건)순이었으며, 자외선차단성분의 경우는 티타늄디옥사이드(81건), 에칠헥실메톡시신나메이트(69건), 징크옥사이드(48건), 에칠헥실살리실레이트(48건), 비스-에칠헥실옥시페놀메톡시페닐트리아진(44건)순이었다. 검사한 100건의 화장품 모두 검출된 살균보존제와 자외선차단성분 함량이 식품의약품안전처에서 정한 사용한도 기준에 적합하였지만 일부 자외선 차단 화장품의 경우 포장 용기에 표시되어 있지 않은 살균보존제와 자외선차단성분이 검출되었다. 100건 중 31건의 화장품에서 표시되지 않은 살균보존제 성분(벤질 알콜 등 6종)이 검출되었고, 2건에서는 표시되지 않은 자외선차단성분(호모살레이트 등 2종)이 검출되었다.

• 조명전기설비학회논문지
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• 제25권5호
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• pp.98-103
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• 2011

Recently, UV(ultra-violet rays) camera has attracted a great deal of interest from the view point of easy judgement in inspections and diagnoses of the safety of power equipment. Especilly, UV camera is applied the inspection of UV with corona discharge. One of the most important and difficult problems is the basic research of filter design, materials and corona discharge. In this paper, we will report on the UV generation, corona pulse count and the polarity effect of positive and negative DC surface discharge in air. Also, corona discharge characteristics are analyzed using prototype UV camera of Korea. UV generation and corona pulse count due to surface discharge in positive needle is higher than that of negative needle.

• Elastomers and Composites
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• 제51권3호
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• pp.226-232
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• 2016

We studied the photocatalytic functionality such as deodorant, antibacterial, fine dust collection efficiency of polyester-based non-woven fabric filter treated with self-actuated photocatalyst. According to UV/visible result, the UV-visible peak of visible-light responsive photocatalyst was found to be red shift at 420 nm sensitive in the visible light region. The deodorizing performance was shown to be reduced more than 80% even without dark conditions. Fine dust particles collection efficiency was shown to be excellent at the size of not only $2.5{\mu}m{\sim}10.0{\mu}m$ but also less than $2.5{\mu}m$. Also antimicrobial and antifungus was shown to be reduced more than 99.9%.

• 한국안광학회지
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• 제9권2호
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• pp.463-471
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• 2004

패브리-페로 형태의 UV용 투과필터를 광학용 설계 프로그램을 이용하여 설계한 후, 설계치를 근거로 하는 두개의 투과필터를 제작하여 광학적 특성을 조사하였다. 투과 영역의 투과율은 반사경으로 사용한 Ag 박막의 두께로 조절하였으며, 투과 파장을 spacer 층으로 사용된 $SiO_2$ 층의 두께로 조절하였다. 시료의 제작은 RF magnetron sputtering법을 이용하였으며, 제작 시료의 구조는 다음과 같다. [air|$SiO_2$(174.6 nm)|Ag(78 nm)|$SiO_2$(68 nm)|Ag(78 nm)|Cr(5 nm)|glass], [air|$SiO_2$(174.6 nm)|Ag(58 nm)|$SiO_2$(56 nm)|Ag(58 nm)|Cr(5 nm)|glass]. 제작한 LV용 투과필터의 광학적 특성은 분광광도계를 이용해서 측정하였다. UV용 투과필터에 의한 투과율은 약 370nm에서 6% 이였으며, 400 nm에서는 0.2% 이하이었다. Ag의 두께를 얇게 함에 따라 투과율을 증가시킬 수 있었으며, spacer 층으로 사용된 $SiO_2$ 층의 두께를 조철하여 투과영역을 조절할 수 있었다.

• 한국물환경학회지
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• 제25권1호
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• pp.90-95
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• 2009

This study investigates the oxidative degradation of N-nitrosodimethylamine (NDMA), a probable human carcinogen, by advanced oxidation process (i.e., UV process). The experiments were performed with various pH, initial concentration, UV intensity, and addition of $H_2O_2$ or $TiO_2$ on UV process. The results showed that the direct UV photolysis was the most effective treatment method. The lower pH, intial concentration and higher intensity of UV stimulated higher NDMA removal. However, addition of oxidant ($H_2O_2$, $TiO_2$) slows down photochemical treatment of NDMA since the oxidant can filter out the UV light and block it to reach the NDMA molecules. Dimethylamine (DMA) and nitrite were found to be a major byproduct from NDMA oxidation. To evaluate the chronic toxicity effects of UV-treated NDMA on the growth of microalgae, "Skeletonema costatum", was studied as long term experiments. Results demonstrated that after the 13 days exposure the chronic toxicity was decreased about 15% with application of UV process on NDMA degradation.

• 상하수도학회지
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• 제29권3호
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• pp.337-345
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• 2015

Two step rapid filter system as a pre-treatment for the injected water into aquifer storage and recovery (ASR) in Korea was developed to reduce physical blockage and secure the volume of the injected water. First, single rapid sand filters with three different media sizes (0.4~0.7, 0.7~1.0 and 1.0~1.4 mm) were tested. Only two sizes (0.4~0.7 and 0.7~1.0 mm) satisfied target turbidity, below 1.0 NTU. However, they showed the fast head loss. To prevent the fast head loss and secure the volume of the injected water, a rapid anthracite filter with roughing media size (2.0~3.4 mm) were installed before a single rapid sand filter. As results, both the target turbidity and reduction of head loss were achieved. It was determined that the media size for a rapid sand filter in two step rapid filter system (i.e. a rapid anthracite filter before a rapid sand filter) was 0.7~1.0 mm. In addition, the effects of coagulant doses on the removal of natural organic matter (NOM), which might cause a biological clogging, were preliminarily evaluated, and the values of $UV_{254}$, dissolved organic carbon (DOC) and SUVA were interpreted.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2003년도 춘계학술대회
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• pp.1881-1884
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• 2003

In this experiment, the oxidations of p-Xylene (140-180 ppmv), one of the air pollutants as a VOC, using $UV/TiO_2$ photocatalyst is studied. In order to increase the specific surface area, the filter is coated by nano $TiO_2$ particles. The photodegradation system consists of a VOCs generator, a photocatalyst filter and a measuring equipment. Illumination is generally provided by two of 20 W black light lamps with 380 nm of wavelength. The filter coated by nano $TiO_2$ particles has a passing efficiency over 80% but a pressure drop of 9.0 $mmH_2O$ at 0.45 cm/s. The filter endurance is better than activated carbon at the same pressure drop.

• 한국전기전자재료학회논문지
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• 제29권1호
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• pp.35-39
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• 2016

In this research, we focused on the improvement of cy3 dye's characteristics for LCD color filter. Solubility and thermal stability are main characteristics of dyes for LCD color filter. We performed experiment to change counter cation of cy3 dyes with alkoxy substituent for these purposes. These cy3 dyes (1b~5b) were prepared through the synthetic procedure of three steps. The synthesized new cy3 dyes were charaterized by using NMR, FT-IR, UV/Vis spectroscopy, and TGA. These cy3 dyes showed purple color and maximum absorption wavelength (${\lambda}_{max}$) in the range of 578~590 nm in UV/Vis spectrum. We confirmed that solubility and thermal stability of cy3 dyes were dependent on the structure of counter cation. Cy3 dyes with alkoxy substituent have good solubility in organic solvents such as dichloromethane, methanol, and acetone. Especially, Cy3 dye with 4-nitrobenzyl counter cation (5b) gave excellent solubility characteristics.

• 한국전기전자재료학회논문지
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• 제26권7호
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• pp.528-533
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• 2013

We focused on the development of red azo colorants with high thermal stability and good solubility for LCD color filter in this research. For the synthesis of hybrid azo colorants, we used the couplers of aniline, naphthol and benzoimidazol functional group. The synthesized hybrid azo colorants were charaterized by using NMR, UV/visible spectroscopy, FT-IR, EA and TGA. They represented the maximum absorption wavelengths which are longer than 500 nm in UV/visible spectrum. So they were confirmed to be suitable for red colorants of LCD color filter. Azo compound (1a, 1b) with aniline functional group had good solubility in organic solvents such as acetone, methanol, chloroform and PGMEA. Moreover azo compounds (1c, 1d and 1e) with naphthol and benzoimidazolone functional group gave excellent thermal stability higher than $250^{\circ}C$ in TGA thermograms.