• Journal of Environmental Health Sciences
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• v.39 no.6
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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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• 2006.04a
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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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• v.4 no.2
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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.

• Journal of Food Hygiene and Safety
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• v.9 no.3
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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.

• Journal of the Korean Society of Propulsion Engineers
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• v.26 no.6
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• pp.74-85
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• 2022

Since the late 1990s, the demand for developing green or reduced-toxic storable propellants has been rising to replace the existing toxic propellants. Most of the research activities are focusing on development of new hypergolic fuels and either white fuming nitric acid or hydrogen peroxide is utilized as an oxidizer. The newly-developed hypergolic fuels are classified as three types, catalytic fuel, reactive fuel, and ionic fuel. In the present study, recent R&D trend of ionic liquid propellants is described and the main results in the previous studies are analyzed.

• Journal of the Korean Society for Marine Environment & Energy
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• v.6 no.3
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• pp.54-62
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• 2003

This paper surveys a number of remotely operated recovery techniques and their recent applications in the removal of the toxic liquid from sunken ships, and suggests the appropriate recovery technique for our ocean environment, especially, in view of its cost and efficiency. Authors also give the technical requirements for the suggested remotely operated recovery system and the basic design result which is well-matched with such requirements.

• Toxicological Research
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• v.4 no.2
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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.

• Journal of environmental and Sanitary engineering
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• v.10 no.2
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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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• v.35 no.9
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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.

• Journal of Life Science
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• v.14 no.2
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• pp.301-308
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• 2004

The morphology of the apical pore complex, the first apical plate and the posterior sulcal plates in a new isolate of Alexandrium tamarense (Lebour) Balech from the Bay of Chinhae was compared with other that of toxic strains of A. tamarense previously isolated from Korean waters. Although this isolate was morphologically identical to these toxic strains, high performance liquid chromatography and mouse bioassay showed no evidence of toxin production. The nontoxic A. tamarense strain showed a strong positive binding activity with PNA lectin, indicating a high density of lactose and galactose residues on the cell surface, and in SDS-PAGE and Western blot analysis a unique protein of about 21-kDa molecular sizes was observed. These findings demonstrate that the use of PNA and immunobioassay could be used to discriminate between toxic and nontoxic strains of A. tamarense.