• 한국환경교육학회지:환경교육
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• 제24권3호
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• pp.18-25
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• 2011

This study was conducted to evaluate the effects of volatile organic compounds and formaldehyde of newly-built school classroom indoor air on the neurobehavioral functions of students. The elementary schools that were opened in September 2008(as of September 2008) was selected for newly-built school and the elementary school that were opened in March 2006 was selected for control group schools. The concentration of formaldehyde(HCHO), a hazardous organic compound that exists in the air of classrooms, exceeded the standard value of $108.2{\mu}g/m^3$ in newly-built schools while it was $60.8{\mu}g/m^3$ in control group schools, which is around 60% of the standard concentration. However, the concentration of the total volatile organic compounds(TVOCs) was $788.9{\mu}g/m^3$ and $756.1{\mu}g/m^3$ in newly-built schools and control group schools respectively, which are approximately two times higher than the standard concentration. In newly-built schools, the mean reaction time of additions and symbol digit, respectively 3,020ms and 2,398ms in pre-exposure were increased to 3,167ms and 2,514ms respectively in post-exposure. The difference of mean reaction time between pre and post exposure was 146.8 ms, or 4.6%, and 116.7ms, or 4.8%, respectively, showing statistically-significant increase of reaction time(p<0.05). On the contrary, the difference of reaction time of both tests were not statistically significant in the control group schools. These results showed that the neurobehavioral performance of newly-built schools students were affected by volatile organic compounds and formaldehyde of classroom indoor air.

• 한국안전학회지
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• 제18권3호
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• pp.94-100
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• 2003

Gel-like compounds containing flammable solvents were prepared to use fur cleaning agents in field of innovative industries and general purposes. And experiments were conducted to improve the defects of liquified flammable solvents from the view point of safety and health hazards. Flammable solvents used in this study were several single component flammable solvents(turpentine oil, N-methyl-2-pyrrolidone(NMP), d-limonene) and multi component flammable solvent(gasoline and ethanol). For gelation of flammable solvents, commercially Known as Aerosil(equation omitted) 200 fumed silica and triethanolamine(TEA) were used as gelation agent dispersant. The analyses on properties of gel-like compounds was studied by gelation and viscosity test pH test, volatility test and differential scanning calorimetry(DSC) measurement. The experimental results indicate that gel-like compounds containing flammable solvents have pH stability, high viscosity, volatile organic compounds(VOC) control by the decrease of volatility and odor component generation, fluidity control etc. From the experimental values, it can be predicted that the safety in the working place is improved by manufacturing flammable solvents into gel-like compounds.

• 미생물학회지
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• 제12권2호
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• pp.53-58
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• 1974

A number of antibiotics and organic compounds were tested for their effect on the multoplication of tobacco mosaic virus(TMV) in floating leaf discs. 1)Among six antibiotics tested, kanamycin sulfate showed 24% or more inhibition to TMV multiplication under these experimental conditions. Aureomycin hydrochloride and chloramphenicol showed 19% and 14% inhibition respectively. 2)For screening of organic compounds two environments were used, a diffuse day- light environment (25 foot-candles and laboratory temperature) and an artificial light environment for 12 hours per day(300 foot-candles at 4 to $5^{\circ}C above laboratory temperature). A wide range of organic compounds increased virus multoplication in the diffuse daylight environment but had less effect, or ingibited virus multiplication, in the artificial light environment. 3)The following compounds were among the most effective in increasing TMV multiplication: glucose-1-phosphate, L-aspartic acid, glucose, and 5-bromouracil. The following compoumds were most effective in inhibiting TMT multiplication: thiouracil, uracil, DL-isoleucine, L-leucine, and zinc chloride.

• 상하수도학회지
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• 제13권3호
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• pp.91-100
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• 1999

Treatment conditions of DAF(Dissolved Air Flotation) and removal rates of VOCs(Volatile Organic Compounds) in mixed water of H raw water and VOCs were investigated. The used VOCs were benzene, toluene, ethylbenzene, and xylene in aromatic compounds and iso propyl mereaptan, n-butyl mereaptan, dimethyl disulfide, and iso butyl mercaptan in odors. The related parameters include water type, treatment method, clay concentration, pH condition, flocculation time, flotation time, per-cent recycle, water temperature, pressure. The removal rates of VOCs were different on treatment process and water condition. Treatment time was longer, removal rates of VOCs was higher. Water temperature was more important than pressure in DAF parameters. Molecular weight was related with removal rate in several kinds of VOCs were decraesed by competition of each component in II raw water. When algac blooming D water was treated by DAF, TCOD(Total chemical Oxygen Demand) and chorophyll a was removed over 96%.

• Bulletin of the Korean Chemical Society
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• 제22권2호
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• pp.171-178
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• 2001

A Purge and Trap Concentrator has been used to analyze various volatile organic compounds in water, operating several parameters affecting the extraction efficiencies of these compounds. The object of the present study was to observe the purge efficiencies of 40 volatile organic compounds (VOCs) in water, according to the change of parameters (purge time, dry purge time, sample temperature), and to determine the optimum condition of analysis of VOCs. The Purge and Trap Concentrator was interfaced with a narrow capillary connected to a gas chromatography mass spectrometer. At this condition, the detection limits of VOCs were in the range of 0.1-0.5 ㎍/L.

• 환경위생공학
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• 제22권3호
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• pp.13-26
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• 2007

Changes in the characteristics of dissolved organic matter was studied at selected stations in the Nakdong river basin using physical and chemical methods. Characteristics of dissolved organic matters were analysed and assessed. Production of disinfection byproducts were also investigated. 1. Result of relatedness study among each items of analyses showed that relatedness on BOD values were highest with cattle excrement treatment facilities where there is no synthetic organic materials and relatedness on $COD_{Mn}$ were highest at the mainstream Nakdong river. In case of $COD_{Cr}$ (which has more oxidative power than $COD_{Mn}$), the values were higher in the sidestreams indicating the higher content of recalcitrant compounds. The relatedness values for the $UV_{254}$ also showed higher values in the sidestreams and treatment facilities than mainstream indicating the presence of organic aromatic compounds. 2. Ratio of DOC on total organic carbon were higher in the mainstream which is attributable to the influent particulate organic materials produced by agricultural activities. The values were 10-15% higher in the mainstream compared with sidestreams. 3. Result of biodegradability test indicate that concentrations of recalcitrant DOC were higher in the sidestreams than in the mainstream. The values of recalcitrant DOC were higher with the forest stream indicating the effect of soil oriented humic substances. 4. Result of THM production test carried out at 10 stations in the Nakdong river show that $CHCl_3$ was detected with the highest value and the value was highest at Waekwan station.

• 한국식품저장유통학회지
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• 제14권3호
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• pp.308-314
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• 2007

천연 약재식물인 옻나무 수피와 그 발효 옻나무 수피의 휘발성 유기성분을 SDE방법으로 추출하고 GC/MS로 분석하여 각각 51종, 27종의 휘발성 유기성분을 확인하였다. 옻나무 수피의 주요 휘발성 유기성 분으로는 2-methyl-3-buten-2-ol, 3-methylbutanal, 1-octen-3-ol, 3-methyl-2-butanone, pentanal, hexanal, ethyl lactate, ethanol 등이 주요 성분으로 전체 성분의 68%를 차지하였으며, 발효 옻나무 수피의 주요 휘발성 유기성분으로는 ethanol이 전체 성분의 68.29%로 나타났고, ethyl lactate, ethyl acetate, 3-methylbutanol 등을 포함한 화합물들이 주요 성분으로 전체의 96%를 차지하였다. 옻나무 수피에서 전체 함량의 1.10 mg/kg를 차지한 ethanol이 발효 옻나무에서는 676.83 mg/kg까지 증가하였다. Ethanol을 제외한 다른 alcohol류는 31.57%에서 6.87%로 감소하였으며, ester류는 4.4%에서 23.7.l%로 증가하였다. 이러한 변화는 발효과정 중의 중간대사산물에 의해서 생성된 것으로 사료되고, alcohol류와 aldehyde류의 감소 그리고 ester류의 상대적 농도의 증가로 다른 화합물들의 화학적 변화에 의한 유도화를 추측 할 수 있었다. 결과적으로, 옻나무 수피가 발효 옻나무 수피로 발효되는 과정에서 맑은 화학적 성분의 변화가 확인 되었다.

• Bulletin of the Korean Chemical Society
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• 제33권8호
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• pp.2597-2602
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• 2012

Novel 1,4-substituted piperazine derivatives 5, Series A and B were designed by fragment analysis and molecular modification of 4 selected piperazine-containing compounds which possess antidepressant activity. We synthesized new 39 analogues of Series A and 10 compounds of Series B, respectively. The antidepressant screening against DA, NE, and serotonin neurotransmitter uptake inhibition was carried out using the Neurotransmitter Transporter Uptake Assay Kit. The compounds in Series B showed relatively higher reuptake inhibitory activity for SERT, NET, and DAT than those in Series A. The length of spacer between the central piperazine core and the terminal phenyl ring substituted at the piperazine ring in Series B seems to exert an important role in the activity.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2001년도 춘계학술대회 논문집 유기절연재료 전자세라믹 방전플라즈마 연구회
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• pp.88-91
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• 2001

The mechanical properties and surface luminous intensities of copper foil have been studied with variation of the amount of additives into the electrolyte. Especially, organic compound of HEC was added from 0.1 to 10ppm for the propose of increasing the mechanical property and the surface state. The total thickness of electrodeposited copper foil was decreased with increasing the amount of organic compounds. There was not so much significant effect of the current density. It has been observed that mechanical property and surface luminous intensity increase with increasing concentration of organic compounds.

• 통합자연과학논문집
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• 제2권3호
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• pp.211-214
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• 2009

A new porous silicon (PSi) microcavity sensor for the detection of volatile organic compounds (VOCs) was developed. PSi microcavity sensor exhibiting unique reflectivity was successfully obtained by an electrochemical etching of silicon wafer. When PSi was fabricated into a structure consisting of two high reflectivity muktilayer mirrors separated by an active layer, a microcavity was formed. This PSi microcavity is very sensitive structures. Reflection spectrum of PSi microcavity indicated that the full-width at half-maximum (FWHM) was of 10 nm and much narrower than that of fluorescent organic molecules or quantum dot. The detection of volatile organic compounds (VOCs) using PSi microcavity was achieved. When the vapor of VOCs condensed in the nanopores, the refractive indices of entire particle increased. When PSi microcavity was exposed to acetone, ether, and toluene, PSi microcavity in reflectivity was red shifted by 28 nm, 33 nm, and 20 nm for 2 sec, respectively.