• 한국환경보건학회지
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• 제39권6호
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• pp.483-491
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• 2013

Objectives: Electronic cigarettes are battery powered devices that convert a nicotine-containing liquid into an inhalable vapor. The device aerosolizes nicotine so that it is readily entrained into the respiratory tract, from where it enters the bloodstream. Information on the safety of E-cigarettes is required. Methods: Seventeen articles on studies analyzing toxic substances in the liquid and gas phases of electronic cigarettes were reviewed. Results: Tobacco-specific nitrosamines, bis(2-ethylhexyl) phthalate, formaldehyde and acetaldehyde, known to be carcinogenic agents in humans or animals, were detected in the liquid and gas phases. In addition, diethyl phthalate, acetone, ethanol, cresol, xylene, propylene, styrene, triethylene glycol, tetraethylene glycol, pentaethylene glycol cis-3-hexen-1-ol, methyl cinnamate and undecane were identified in the liquid and gas phases of E-cigarettes. Propylene glycol, glycerin, 1-methoxy-2-propanol, 1-hydroxy-2- propanone, acetic acid, 1-menthone, 2,3-butanediol, menthol, carvone, maple lactone, benzyl alcohol, 2-methyl-2-pentanoic acid, ethyl mantel, ethyl cinnamate, myosamine, benzoic acid, 2,3-bipyridine, cotinine, hexadecanoic acid, and 1'1-oxybis-2-propanol were detected in the vapors of E-cigarettes. Conclusion: The hazardous compounds identified in the liquid and gas phases of E-cigarettes should be controlled for the lowest concentrations in the raw materials and production procedures.

• 한국연소학회:학술대회논문집
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• 한국연소학회 2006년도 제32회 KOSCO SYMPOSIUM 논문집
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• pp.75-78
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• 2006

Disposal of highly toxic wastes like polychlorinated biphenyls (PCBs) is very difficult. These substances create a growing mountain of problematic waste that has to be disposed properly. Conventional technologies that are based on common burning(rotary kiln, ${\sim}1100^{\circ}C$) and plasma technology(${\sim}10000^{\circ}C$) do not satisfy important conditions. for example, complete combustion of the toxic waste and the price of waste disposal. The combustor like a rocket engine is operated at relatively high pressure(${\sim}15$ bar) and relatively high temperature(>$3000^{\circ}C$) that are ideal for the complete destruction of extremely toxic substances. In this study, test compound($_o-DCB$) was dissolved in kerosine with a concentration of 10%. Pure gas oxygen was used as an oxidant. Analysis showed that the destruction efficiency achieved for ${o}-DCB$ was 99.9999% or better. The results show that a combustor based on liquid propllant rocket technology is a validated tool for the disposal of highly toxic waste, and a good alternative technology when applied to the destruction of extremely toxic wastes.

• Membrane and Water Treatment
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• 제4권2호
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• pp.95-108
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• 2013

Metal ions exist in seawater, groundwater and industrial wastewaters. These source waters can be recycled if their concentrations are reduced. A number of processes can be applied for this purpose. Liquid-liquid extraction is one of the promising methods. In this paper, experimental results are presented on the removal of Cr(VI) using Aliquat-336, a reactive carrier, in sunflower oil (a non-toxic solvent). The performance of this new system is compared with those of kerosene (a toxic solvent). The extent of removal of Cr(VI) from samples with high and low concentrations are presented. The process was upgraded to a bench-scale module that can selectively remove about 50-90% Cr(VI) from samples of groundwater. Thus this process can produce water within the acceptable range for recycling and for use in secondary purposes such as irrigation.

• 한국식품위생안전성학회지
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• 제9권3호
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• pp.111-116
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• 1994

The acute toxicity of orally administered Yan-Sheng health liquid (YSHL), water extracts from twelve Chinese drugs (Cervi Cornu, Lonicerae Flos, Foeniculi Fructus, Glycyrrhizae Radix, Liriopis Tuber, Raphani Semen, Bombyx, Ginseng Radix alba, Cinnamomi loureirii Cortex, Epimedii Herba, Zingiberis Rhizoma, Lycii Fructus) was evaluated in male and female Sprague-Dawley rats and ICR mice. Rats and mice aging 5 weeks were gavaged with 0, 2.0, 3.0, 4.4, 6.7, 10.0, 66.7, or 100.0 ml/kg of YSHL. No animal died by oral treatment and no toxic symptom was observed in the treated animals during 5 days. The body weight of the treated animals was not significantly different from the controls. The results of macroscopic examination on the organs of the treated animals revealed no abnormal findings. Therefore, it was concluded that YSHL was practically non-toxic when it was orally administered to rats and mice, and its LD50 was suspected to be greater than 100 ml/kg in rats and mice.

• 한국추진공학회지
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• 제26권6호
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• pp.74-85
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• 2022

1990년대부터 기존 맹독성 이원추진제를 대체하기 위해 수행되어 오던 친환경 혹은 저독성 이원추진제 조합에 관한 연구는 최근 우주 추진기술 개발과정에서 경제성, 안정성, 효율성 등이 강조되며 더욱 주목받고 있다. 연구활동은 주로 저독성 하이퍼골릭 연료를 개발하는 것에 집중되어 왔으며 백연질산 혹은 고농도 과산화수소 산화제로 사용하였다. 저독성 하이퍼골릭 연료의 종류는 촉매성 연료, 반응성 연료, 이온성 연료로 구분할 수 있다. 본 논문에서는 하이퍼골릭 이온성 연료의 연구개발 동향을 소개하고 선행연구에서 보고된 주요 결과들에 대해 분석하고자 한다.

• 한국해양환경ㆍ에너지학회지
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• 제6권3호
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• pp.54-62
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• 2003

본 연구에서는 다양한 침몰선박 잔존유회수 방법 중에서 안전성과 경제성을 바탕으로 우리나라 해역특성에 적합한 무인 원격회수방법을 선정하였다. 이와 함께 우리나라 전 연안에서 회수작업을 실행할 수 있는 작업 수심 200m급 잔존유 무인회수시스템(Remotely Operated Recovery System)의 요구사양을 선정하고 회수장비에 대한 기본설계를 수행하였다.

• Toxicological Research
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• 제4권2호
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• pp.85-94
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• 1988

In order to elucidate the mechanism of toxic action of a pisonous mushroom, Amanita pantherina, biochemical effects of the mushroom extracts on mice were studied. A hotwater extract of Amanita pantherina injected intraperitoneally into male ICR mice evoked signs similar to those observed clinically upon acute poisoning by the mushroom and also changed the levels of component enzyme activities in blood, liver and urine. The serum cholinesterase activity was decreased significantly during 1-3 h after injection.

• 환경위생공학
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• 제10권2호
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• pp.59-66
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• 1995

According to the population increase and industrialization, the drinking water source, Han River and other sources, are contaminated by industrial wastewater, domestic sewage, and agricultural discharges. Among the contaminants, and toxic substances, pesticides is most interesting items (or human health Our drinking water has some problems of THMs, Fe, odor, etc., $o many people use groundwater or bottled water. But sometimes there are many reports about groundwater contamination owing to the agricultural chemicals, waste disposal, industrial wastewater. In America, there are about 45,000 groundwave supply company and in korea about 20% of total population are using groundwave as drinking water source. In America, studies about SEE is increasing Instead of liquid- liquid extraction method, because of many advantages of SEE methods. Author tried to investigate SPE methods in the spiked water samples to compare with liquid- liquid extraction method and got the following results. The amount of organic solvents which are used In SPE method is less than 1/10 compared with liquid- liquid method, the analytical duration time is shortened, and the ethyl acetate was good fluent among several organic solvents.

• Bulletin of the Korean Chemical Society
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• 제35권9호
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• pp.2704-2710
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• 2014

Catalase (CAT) decomposes hydrogen peroxide that is toxic to the body. In this study, simple and sensitive detector has been developed for observing catalase activity using liquid crystal droplet system. Microscale LC droplet patterns are formed by spreading aldehyde-doped nematic liquid crystal on pre-treated glass slides. When hydrogen peroxide is added, aldehyde is oxidized and amphiphiles are formed. Dodecanoates cause the pattern to transit from bright to dark as they self-assemble to form a carboxyalte monolayer at the interface. When a drop of pre-incubated CAT and hydrogen peroxide mixture is placed onto the pattern, bright fan-shape is observed. This planar optical appearance indicates that catalase has decomposed hydrogen peroxide. Compared to the detectors that have been previously developed, this system is more sensitive with detection limit of 1fM. This research suggests further studies to be on LC droplet patterning to develop highly sensitive and methodologically simple sensors for various chemicals.

• 생명과학회지
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• 제14권2호
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• pp.301-308
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• 2004

진해만에서 분리한 무독성 Alexandrium tamarense와 이미 보고된 독성을 가진 A. tamarense종 간의 접속공, 제1상판, 후속공의 형태를 상호 비교하였다. 형태적으로 독성종과 거의 일치되지만, HPLC나 생체실험에서 진해만에서 새롭게 분리한 종은 독성이 전혀 나타나지 않았다. lectin반응결과 무독종 A. tamarense은 PNA와 강한 반응을 보여, 세포표면에 lactose나 galactose와 같은 물질이 많이 분포하고 있음을 보였다. 또한, 단백질 전기영동시 무독종은 유독종과 달리 21 kDa 정도 부위에서 종 특이적 밴드를 보였다. 따라서 PNA lectin이나 면역학적 방법을 이용하면 무독종 A. famarense을 신속하게 동정하는데 이용될 수 있다.