• Journal of agriculture & life science
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• v.45 no.6
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• pp.141-150
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• 2011

In order to elucidate a flavor characteristics of the low-salt fermented ascidian (LFA), a volatile flavor constituents were extracted and analyzed by SDE apparatus and GC/MS. Salinity, pH and volatile basic nitrogen of the LFA were 8.0%, 5.17 and 23.0 mg/100 g, respectively. Total content of volatile flavor compounds identified from the LFA was $1,221.42{\mu}g/100g$ as cyclohexanol (internal standard), it were composed of 23 alcohols ($644.85{\mu}g/100g$) such as 1-octanol and 2-pentanol, 16 acids ($293.91{\mu}g/100g$) such as 2-hydroxy-propanoic acid and butanoic acid, 15 aldehydes ($153.61{\mu}g/100g$) such as trans-2-hexanal and benzaldehyde, 29 hydrocarbons ($97.65{\mu}g/100g$) such as 1,4-dimehyl-cyclooctane and 1-nonene, six aromatic compounds ($6.20{\mu}g/100g$), two esters ($2.07{\mu}g/100g$), two nitrogen-containing compounds ($19.09{\mu}g/100g$) and three micellaneous compounds ($4.04{\mu}g/100g$).

• Journal of Life Science
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• v.18 no.11
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• pp.1570-1577
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• 2008

For useful basic data in developing of Omandungi (Styela plicata) processed products, volatile flavor compounds were analyzed to identify the key reaction flavor compounds induced through heat treatment ($100^{\circ}C$, 10 min) in Omandungi -Doenjang (soybean paste) soups and stew. A total of 128 flavor compounds were identified and composed mainly of esters (16), aromatic compounds (14), N-containing compounds (11), alcohols (34), terpenes (5), carbonyl compounds (23), furans (4), hydrocarbons (13), acids (5) and miscellaneous compounds (3). Three groups including aromatic compounds, alcohols and acids were detected in high amounts in Doenjang. However, the levels of C4-C6 series acids (i.e., pentanoic acid having off-flavor) decreased by cooking ($100^{\circ}C$, 10 min), whereas that of furans (i.e., furfural) as heat induced compounds increased 2 times. Alcohols were detected the major group in Omandungi and followed by hydrocarbons and aromatic compounds in that order. In particular, 3 compounds including decenol, 2,6-dimethylheptanol and octanol were the major alcohols of Omandungi. By cooking, the compounds known heat-induced compound, 2-acetyl-2-thiazoline and benzothiazole, were newly formed in Omandungi-Doenjang stew. The alcohols (i.e., decenol, 2,6-dimethylheptanol), hydrocarbons and aromatic compounds derived from Omandungi were supposed to enhance a seafood-like flavor in Omandungi-Doenjang stew.

• Elastomers and Composites
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• v.47 no.3
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• pp.216-222
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• 2012

In this study, p-acryloyloxybenzoic acid(ABA) was synthesized with p-hydroxybenzoic acid(HBA) and acryloyl chloride(AC). The synthesized ABA monomer was grafted onto ethylene-propylene-diene rubber(EPDM) in toluene using benzoyl peroxide(BPO) as an initiator. The structures of ABA and EPDM-g-ABA were characterized by FT-IR, $^1H$-NMR, and $^{13}C$-NMR spectrometer. The graft ratio of EPDM-g-ABA increased with increasing the concentration of the initiator and the monomer. Mechanical properties such as tensile strength and compression set of the EPDM-g-ABA were improved with increasing the graft ratio. The $T_g$ and initial decomposition temperature were also increased with increasing the graft ratio.

• The Korean Journal of Malacology
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• v.14 no.2
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• pp.113-120
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• 1998

참굴에 다환성방향족탄화수소(PAHs)의 축적성과 이 물질들이 미치는 독성을 평가하기 위해 해양환경에서 빈번히 검출되는 PAHs 중의 하나인 anthracene을 사용한 모델연구를 수행하였다. Anthracene을 0.01-1ppm의 농도로 2주간 참굴에 노출시켰을 때 참굴 조직내의 anthracene의 농도는 노출기간 및 노출강도에 비례하여 최고 25-85배까지 증가하였다. 소화맹낭과 폐각근의 지질 과산화물가는 노출기간 및 노출농도에 관련하여 현저히 증가하였으나 수용성단백질, glycogen, nucleoside/nucleotide 및 핵산의 함량은 변화하지 않았다. 이 결과로 anthracene은 굴의 조직내로 원할하게 축적됨을 확인하였으며 과산화지질의 함량은 anthracene에의 오염에 대한 예민한 생화학적 지표가 될 수 있을 것으로 사료된다.

• Applied Chemistry for Engineering
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• v.17 no.2
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• pp.177-182
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• 2006

In this work, we have prepared organophilic MMT having thermal stability by ion exchange reaction of various aromatic ammonium salts with MMT containing sodium ion. The organic modifiers having alkyl side chains and amine functional group were successfully synthesized by effectively introducing the surfaces of MMT via ion exchange reaction to form organophilic MMTs with a view to improve the reactivity and thermal stability. The WAXD patterns of organophilic MMT showed the more increased gallery spacing by $3.3{\AA}$ than that of the pristine MMT and also the onset of initial decomposition of organophilic MMT was $275^{\circ}C$ as determined by a thermogravimetric analysis. The polyimide (PI) nanocomposite films based on poly(amic acid) and organophilic MMT were prepared by a solution blending followed by cyclodehydration reaction. We have investigated the dispersity of organophilic MMTs in PI matrix by using WAXD and the effect of the organophilic MMT content on the mechanical properties of PI nanocomposite films was studied.

• Journal of Adhesion and Interface
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• v.10 no.4
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• pp.169-173
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• 2009

In this study, We were studied on the properties of polyurethane elastomer containing the polyol, chain extender and isocyanate in polyurethane elastomer. Polyurethane elastomer had the best properties with poly(tetramethylene) glycol for in-line skate wheel. With more incorporation of chain extender content in polyurethane elastomer, tensile strength and hardness increased and elongation decreased. And then properties of polyurethane elastomer with the bulky type isocyanate had better than the flexible type isocyanate.

• The Korean Journal of Zoology
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• v.38 no.2
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• pp.238-247
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• 1995

쥐 뇌에·처 카드뮴에 대한 metallothionein-like protein(MTLP)의 유도 생성 능력을 알아보기 위하여 Stereotaxic Bpparatus를 이용하여 측뇌실에 카드뮴을 주사하여 다음과 같은 결과를 얻었다. 대조군과 생리식염수 처리군에서는 MTLP의 양적 변화가 없었고. 카드를 처리군은 대조군과 식염수 처리군에 비하여 MTLP가 2배 이상 유도되었다. MTLP의 분자량은 6.000-6,500 Oa 정도 였으며. 흡광도가 254 nm에서 높게 나타나고. 280 nm에서 낮게 나타나는 것으로 보아 thiol 함량이 높고 방향족 아미노산이 적은 단백질임을 알 수 있었다 또한 카드뮴 처리군에서는 MTLP 이외의 여러 종류의 protein-30. 64, 68, 80, 108 kDa-들이 유도되었다 이와 같은 결과로 카드뮴은 흰쥐 뇌에서도 MTLP의 유도 능력이 있음을 알 수 있었다.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.13 no.11
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• pp.5637-5645
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• 2012

To enhance the reutilization of waste skate skin for the functional food resources, the investigations of extraction characteristics, antioxidative activity of skate skin water extracts on the oxidation of three cooking oils were carried out, and rheological properties, storage safety and sensory evaluation of collagen gel from skate skin were performed. Aromatic and phenolic compounds contents of $50^{\circ}C$ extracts were higher by 49.4% and 32.7%, respectively, than those of $25^{\circ}C$ extracts. Reducing power of extract at $50^{\circ}C$ was higher by 52.74% than that of $25^{\circ}C$ extract, but was 14.9% of ascorbic acid and 27.8% of BHT. Electron donating ability was corresponded to reducing power and phenolic compounds contents. Antioxidative effect of extracts on cooking oil was higher at $50^{\circ}C$ extract than $25^{\circ}C$ extract, and its order was on corn seed oil, soybean oil and olive oil. Antioxidative effect of $50^{\circ}C$ extract showed 38.27~96.83% and 49.53~75.31% of those of ascorbic acid and BHT, respectively, over three cooking oil. The optimum extraction condition for collagen gellation was $100^{\circ}C$, 2 hours extraction under 2.5 folds hydrolysis, and gel strength was lowered above 50% by 10% seasoning.

• Journal of the Korean Wood Science and Technology
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• v.34 no.6
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• pp.36-43
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• 2006

Using fluidized bed type fast pyrolysis system (capacity 400 g/h) bio-oils were produced from beech (Fagus sylvatica) and softwood mixture (spruce and larch, 50:50). The pyrolysis was performed for 1~2 s at the temperature of $470{\pm}5^{\circ}C$. Pyrolysis products consisted of liquid form of bio-oil, char and gases. In beech wood bio-oil was formed to ca. 60% based on dry biomass weight and the yield of bio-oil was 49% in soft wood mixture. The moisture contents in both bio-oils were ranged between 17% and 22% and the bio-oil's density was measured to $1.2kg/{\ell}$. Bio-oils were composed of 45% carbon, 47% oxygen, 7% hydrogen and lower than 1% nitrogen,which was very similar to those of original biomass. In comparison with oils from fossil resources, oxygen content was very high in bio-oils, while no sulfur was found. More than 90 low molecular weight components, classified to aromatic and non aromatic compounds, were identified in bio-oils by gas chromatographic analysis, which amounted to 31~33% based on the dry weight of bio-oils.

• Economic and Environmental Geology
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• v.37 no.6 s.169
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• pp.613-629
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• 2004

Contamination of groundwater by volatile organic compounds (VOCs) was investigated for 168 groundwater wells in Ulsan area to study the natural attenuation of organic compounds in the aquifers. As groundwater contamination by VOCs is closely related to land use, 168 groundwater samples were classified into 4 different groups; agricultural, forestry, industrial, and residential & business. From analysis 65 out of 168 groundwater samples contained more than one VOC. Analysis of samples were performed fir 36 halogenated aliphatic hydrocarbons and 25 petroleum hydrocarbons set up by NAWQA of US geological survey. Twelve petroleum hydrocarbons were detected in 26 groundwater wells, but their concentrations were less than 1.5 g/L except for MTBE. Twenty three chlorinated aliphatic hydrocarbons, composed of 11 methanes, 6 ethanes and 6 ethenes, were detected in 63 groundwater samples. The range of methanes concentration was $ND\~330\;/gL,\;ethanes\;ND\~84\;gL$, and PCE and their derivatives $ND\~62\;g/L$. As the study area was comprised of the aerobic/denitrification zones and $Fe^{+3}$ redox condition, most of petroleum hydrocarbons were degraded well, while halogenated hydrocarbons were slowly biodegradation.