• Proceedings of the Korea Air Pollution Research Association Conference
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• 2000.04a
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• pp.265-266
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• 2000

휘발성 유기화합물(VOCs)은 새로운 유형의 스모그의 광화학반응 촉진제로서의 작용 및 환경학적 문제점들을 제기하고 있으며 공단 주변의 악취발생 및 환경 오염사건등을 유발시키고 있다. 이러한 휘발성 유기화합물을 적절하게 제어할 수 있는 방지대책의 여러 가지 방법들이 국내외적으로 활발히 연구되어지고 있다. 산업현장에서 이들 휘발성유기화합물의 배출을 제어하기 위한 기술 보유 및 개발에 있어서는 아직까지 미비한 단계에 있으며 보유기술의 현장적용의 측면에서 휘발성유기화합물이 지니고 있는 특이한 물리적 성질 등에 의해 많은 어려움을 가진다. (중략)

• The Journal of Engineering Research
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• v.6 no.2
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• pp.119-124
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• 2004

In this research montmorillonite intercalations complexes as organophilic clay compounds which have very different properties as the starting clay mineral were synthesized by the substitution of metal ions which exist in the montmorillonite layers with the organic cations which have long alkyl chain by the cation exchange reaction. Thereafter the obtained products dried in high vacuum were treated with the various swelling liquids such as dist. water, methanol, acetone, ether and acetonitrile in order to know the swelling behaviour of the synthesized complexes. Especially for this research Korean and Turkish clays were selected to compare the intercalations complexes of both clays and their swelling behaviour.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.25 no.3
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• pp.67-80
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• 2020

Zinc (Zn) is known as an essential micronutrient for phytoplankton in the ocean. In surface waters, most of total dissolved Zn presents as organic complexes, and organic complexation dominates the speciation of Zn in seawater. Organic complexation reduces the bioavailable fraction of Zn, the free metal ion (Zn²⁺), which present less than 5% in surface waters. In this paper, a brief introduction on chemical speciation of dissolved Zn in seawater and analytical method for chemical speciation measurement is provided. Some representative studies were also introduced to describe the importance of chemical speciation of Zn (or other trace metals) on bioavailability and biogeochemistry in the ocean.

• Food Science and Preservation
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• v.17 no.1
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• pp.151-159
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• 2010

Changes in volatile organic compounds were investigated during storage after electron beam irradiation. Grapes were irradiated at 0.25, 0.5, 0.75, and 1.0 kGy and stored for 1 month at $4^{\circ}C$. Butanol, hexanal, [E]-2-hexenal, hexanol, and 3-methyl-butanol were the major volatile organic compounds of grapes. The types of volatiles in irradiated grapes were similar to those of non-irradiated samples but concentration differed among treatments. Some volatile compounds decreased during storage, whereas others, especially the esters, increased. Concentration of most volatile compounds were higher in pre-stored grapes than in post-stored fruit (thus, during the 30 days after irradiation by e-beam). Consequently, concentration of volatile organic compounds either increased or decreased after e-beam irradiation but these changes did not correlate with irradiation dose.

• Proceedings of the Korea Society of Environmental Biology Conference
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• 2002.11a
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• pp.25-32
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• 2002

유기주석화합물은 선박방오도료에 살생물제로 쓰이는 독성이 강한 물질로서 내분비계장애물질의 일종으로 알려지고 있다. 광양만에서 유기주석화합물의 오염현황을 파악하고자 표층퇴적물 및 생물체 중의 농도를 정성 및 정량분석하였으며, 생물에 미치는 영향을 파악하고자 복족류의 임포섹스(암컷에서 수컷의 성기가 발현되는 현상)를 측정하였다. 표층퇴적물 및 생물체 체내에서 phenyltin은 일부 정점을 제외하고는 모두 검출한계 이하의 값을 보였으나, butyltin은 대부분의 정점에서 검출되었다. 표층퇴적물, 참굴, 대수리 체내의 tributyltin (TBT)의 농도는 각각 미검출-29 ng/g, 178-2458 ng/g, 47-236 ng/g 범위를 보였다. TBT 화합물의 공간적인 분포는 선박활동과 밀접한 관련이 있었으며, 항구가 위치한 여수 인근을 제외하고는 광양내만에서 상대적으로 높은 값을 보였다. 한편 대수리 중의 임포섹스는 11개 정점에서 모두 관찰되었으며, 상대성기길이 지수는 47.9-107.8%의 범위를 보였다.

• Journal of the Korean Chemical Society
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• v.50 no.1
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• pp.60-64
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• 2006

has been synthesized using the layered organic-inorganic hybrids, Cu2(OH)3(CH3COO)·H2O as a precursor. Cubic Cu2O is synthesized by reducing Cu2(OH)3(CH3COO)·H2O with glucose in water at 75oC. The effects of precursor and glucose are investigated. The structure of Cu2(OH)3(CH3COO)·H2O plays an important role in preparing the uniform size of Cu2O.

• Journal of the Korean Society of Food Science and Nutrition
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• v.34 no.4
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• pp.513-518
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• 2005

Volatile compounds of $\gamma-irradiation$ leeks (Aillum tuberosum R.) were isolated by simultaneous steam distillation and extraction method (SDE) and analyzed by gas chromatography/mass spectrometry (GC/MS) along with the non-irradiated sample. Leeks were irradiated at dose of 20 kGy and non-irradiated samples were considered as control sample. 56 and 54 compounds were identified in non-irradiated and irradiated samples, respectively. These components included the functional groups; alcohols, aldehydes, esters, ketones, N- and S-containing compounds. S-containing compounds such as dimethyl trisulfide, methyl-(Z)-l-proenyl trisulfide, dimethyl disulfide, 3-ethyl-l,2-dithi-5-ene and methyl allyl disulfide were the major compounds. Methyl-(Z)-l-propenyl trisulfide, diallyl trisulfide, (E)-2-hexanal and 3-ethyl-l,2-dithi-5-ene were clearly decreased by the $\gamma-irradiation$, but dimethyl disulfide, diallyl sulfide, allyl methyl sulfide and pyridine were increased by the $\gamma-irradiation$.

• KSBB Journal
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• v.11 no.6
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• pp.726-732
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• 1996

Selective adsorption of plant metabolites from a polar dilute solution onto a polycarboxyl ester sorbent (XAD-7) was investigated. Experimental results demonstrated that neutral resins could selectively concentrate specific flavonoids from dilute aqueous mixtures. Adsorption was dependent on the pH of medium, dosage of the resins and medium composition. Especially the medium composition was a key factor for the selective adsorption and it was found that the selective adsorption was dependent on specific sorbent-sorbate-medium characteristics. Under the optimum condition, selectivity increased up to 85% and the yield of recovery was approached to 98%. It was also found that XAD-7 adsorbed flavonoids in the order of hydrophobicity.

• The Korean Journal of Ecology
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• v.24 no.1
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• pp.19-26
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• 2001

Tributyltn, triphenyltin and their degradation products were quantitatively determined in sediments, seawater, and oysters (Crassostrea gigas) collected from Okpo Bay, Korea where a huge shipyard was located. The concentrations of TBT in sediment and oyster were in the range of 5∼2,050 ng/g and 387∼1,190 ng/g (astin on a dry weight basis), respectively. In seawater, it ranged from 19 to 84 ng/ℓ The distribution of TBT compound showed negative gradient from inner to outer bay, which indicates that the shipyard is the point source of TBT contamination in the bay. The contribution of TBT to butyltin concentration in sediment was above 57%. The pattern of TBT distribution was influenced by waterbreak transected the bay. TPhT concentration in oyster ranged from nd (not detected) to 52 ng Sn/g dry wt., whereas that in sediment and seawater was below detection limit. The biological concentration factor (BCF) in oyster was 1.1×10⁴.

• Membrane Journal
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• v.10 no.4
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• pp.198-204
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• 2000

Pervaporation membranes were fabricated by low temperature plasma treatment the concentrate butanol solution from fermentation process. Effects of power, reaction time, and monomer flow rate were examined to optimize the (W!FM)t value as 4.0389 x 109 J . min/kg. Various organic compounds were tested in plasma treatment. Contact angle and relative sorption ratio were examined in terms of membrane performance. With the increase of contact angle and relative sorption ratio separation factor was enhanced from 0.186 to 3.525. and butanol flux increased from 0.042 to 0.567 kglm2. hr. Hydrophobicity of the membrane increased the affinity with butanoL Heat of mixing for monomer with butanol was examined, but failed to find the trend, because plasma polymerization of monomer produced the new compounds much different from monomers.