• Journal of Microbiology and Biotechnology
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• 제13권5호
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• pp.647-650
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• 2003

In anhydrous organic solvents, the complexes formed between AOT (dodecylbenzene sulfuric acid sodium salt) and hemoproteins, such as hemoglobin, myoglobin, or cytochrome c, displayed remarkably higher activity than the hemoprotein powders to oxidize dibenzothiophene, a model compound of organic sulfurs contained in fossil fuels. In slightly hydrophobic organic solvents, such as ethyl acetate and butyl acetate, dibenzothiophene was completely oxidized catalytically by the cytochrome c-AOT complex with cumene hydroperoxide (${\alpha},{\alpha}-dimethylbenzyl$ hydroperoxide) as an oxidant. In highly hydrophobic organic solvents, such as decane and hexadecane, however, the activity of the cytochrome c-AOT complex decreased, presumably due to the aggregation of the hemoprotein-AOT complex in these solvents.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2014년도 춘계 학술논문 발표대회
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• pp.216-217
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• 2014

Optimum finishing position, thickness and phase change temperature of winter and summer season were selected and suitability of finishing materials was evaluated based on temperature measurement of specimens applying the coating material mixed phase change materials(PCM). As a result, when finishing position was interior and finishing thickness of coating material mixed n-Octadecane(28℃ PCM) was 4mm, thermal performance was effective. n-Octadecane in summer season and n-Hexadecane(18℃ PCM) in winter season are indicated effective on energy savings, respectively.

• 대한기계학회논문집
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• 제11권4호
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• pp.629-636
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• 1987

An experiment is carried out to study the surface-tension driven flow characteristics in a cylindrical liquid column heated from above (which is the low gravity floating zone simulated on earth) with varing the aspect ratio and diameter of the liquid column. Hexadecane, octadecane, silicon oil(10cs), FC-40 and water are used as the test liquids. The free surface shape varies sinusoidally for Ma>M $a_{cr}$ and its frequency is found to be the same as that of temperature oscillation. It is verified that the surface temperature profile changes from linear to S-shaped profile for Ma>M $a_{cr}$ . The frequency of temperature oscillation decreases with increasing liquid volume, while its level increases. M $a_{cr}$ decreases with increasing aspect ratio, and also decreases with increasing Prandtl number in the range of 25

• Environmental Sciences Bulletin of The Korean Environmental Sciences Society
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• 제4권4호
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• pp.221-225
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• 2000

Pseudomonas sp. EL-G527 was grown to produce a biosurfactant on 2% n-hexadecane as the energy and carbon source. This biosurfactant significantly reduced the surface tension of water from 72 to 28 dyne/cm at a critical micelle concentration(CMC) of 140 mg/l at pH 2.0. As the pH value decreased, the reduction in the surface tension due to the biosurfactant increased. The surface activity of the biosurfactant was unaffected when the NaCl concentration was increased to 5% and the calcium ion concentration increased to 100 mM, plus it remained stable at 10$0^{\circ}C$ for 180 min.

• 한국미생물·생명공학회지
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• 제24권2호
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• pp.206-212
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• 1996

The strain producing bioemulsifier was isolated from soil samples. The isolated strain was identified as the genus Acinetobacter through its morphological, cultural and physiological characteristics. The highest emulsification activity and stability by Acinetobacter sp. BE-254 was observed after 5 days of cultivation in the culture medium containing n-hexadecane 4%, NaNO$_{3}$ 0.2%, KH$_{2}$PO$_{4}$ 0.01%, MgSO$_{4}$-7H$_{2}$O 0.01%, CaCl$_{2}$ 0.01%, and yeast extract 0.01%. The optimum pH and temperature for bioemulsifier production were pH 7.0 and 30$\circ$C, respectively. Furthermore the most of bioemulsifier was produced during the exponential growth phase, and this suggested that the bioemulsifier production was growth-associated. The bioemulsifier showed good emulsification activity on various emulsifying substrates such as hydrocarbons, edible oils, and petroleum fractions.

• Journal of Microbiology
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• 제39권4호
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• pp.326-330
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• 2001

Mycobacterium sp. C2-3 was isolated from petroleum contaminated soil around an oil reservoir and identified by analysis of its 16S rRNA gene sequence, Strain C2-3 was able to use fluorene, phenan-threne, fluorathene and pyene as sole sources of carbon and energy, yet unable to geagrade naph-thalene, The strain was also able to use n-alkanes, such as hexadecane and heptadecane, and phenanthrene and pyrene, in particular, were degraded rapidly,. The phylogenetic data suggested that the isolate C2-3 is a thermosensitive, fast-growin strain of Mycobacterium sp.

• 한국의류학회지
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• 제15권4호
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• pp.437-445
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• 1991

The effect of diameter of rods or fibers on contact angle was studied in a vertical rod configuration. A contact angle measuring device described in the previous paper was optimized for the measurement of small-diameter fibers. It was shown that contact angles of water and hexadecane on nylon 6 monofilsments and glass rods increased with decrease of diameter below a critical diameter, which varied from one system to another. Beyond the critical value, contact angle of the liquid on the vertical glass rod reached to an equilibrium value which is equal to the unique value of the contact angle of the liquid drop on the horizontal glass plate.

• Journal of Advanced Marine Engineering and Technology
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• 제22권4호
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• pp.551-559
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• 1998

Evaporation and ignition characteristics of fuel droplet have major influences on the efficiency and performance of engine. In the present study the experiment of evaporation and self-ignition of single fuel was performed under the various ambient conditions. An individually suspended droplet of n-heptane n-hexadecane ethyl-alcohol and light oil were employed as a liquid droplet. Evaporation and ignition characteristics were measured by using the video-camera and image processing technique under the various ambient temperatures (up to 1000310 OC)and partial pressure of oxigen(up to 60%) The evaporation curve shows that the droplet life time ignition delay time decreases as the ambient temperature and partial pressure of oxigen increase, The temperature variations of droplet were also reported for various fuel and ambient temperatures. The numerical simulations were carried out to predict droplet diameter and temperature with favorable agreement.

• Bulletin of the Korean Chemical Society
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• 제11권5호
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• pp.431-434
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• 1990

Template condensation reaction of diethylenetriamine, ethylenediamine, methylamine, and formaldehyde in the presence of Ni(II) or Cu(II) ion yields new saturated hexaaza macrobicyclic complexes $[Ni(C)]^{2+}\;and\;[Cu(C)]^{2+}$, where C is 8-methyl-1,3,6,8,10,13-hexaazabicyclo[11,2,1]hexad ecane. The macrobicyclic complexes contain one 1,3-diazacyclopentane ring and one methyl pendant arm in the ligand C and have square planar geometry with 5-6-5-6 chelate ring sequence. Synthesis, characterization, and the properties of the macrobicyclic complexes are described.

• 한국식품조리과학회지
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• 제22권6호통권96호
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• pp.774-782
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• 2006

갓 채취한 야산재배 더덕의 휘발성 향기성분을 Head space sampling 방법으로 추출하고 GC/MS로 분석한 결과 terpene 및 terpene alcohol류 28종, hydrocarbon류 34종, alcohol류 31종, aldehyde 및 ketone류 13종, ester류 25종, acid류 6종, ether류 10종 등 총 167 종의 휘발성 향기성분을 확인하였다. 크로마토그램 상에서 차지하는 면적 비율이 큰 10대 주요 휘발성 성분은 dl-limonene(10.2%), ${\alpha}$-guaiene(9.0%), 2,2,6-trimethyl-octane(8.6%), hexadecane(8.0%), isolongifolan-8-ol(4.2%), 2,4,4-trimethyl-1,3-pentanediol diisobutyrate(4.1%), ${\beta}$-selinene(3.9%), 2,2,3-trimethylnonane(3.6%), 3-methyl-5-propyl-nonane(3.1%), 및 ledene(3.1%) 등으로 주로 20분 이내와 40${\sim}$60분 범위에서 나타났으며, 전체의 58%를 차지하였다. 식품의 향기는 기계적 분석 결과만으로 설명하기 어려우므로 전문 조향사들의 도움을 받아 관능평가를 실시하였으며, 그 결과 신선 더덕의 향기 특성으로 풋냄새, 흙냄새, 우유발효 냄새 및 장뇌냄새 등이 묘사되었다. 이러한 향기 특성을 GC/MS에서 확인된 20대 주요 휘발성 성분들과 관련시켜 보면, dl-limonene은 풋냄새 성분이며, ${\alpha}$-guaiene과 isolongifolan-8-ol은 흙냄새를, 우유발효취를 내는 성분들에는 2,2,6-trimethyloctane, hexadecane, 3-methyl-5-propylnonane, 2,2,3-trimethylnonane 등이 속하였다. 이 외에 과일향을 내는 2,4,4-trimethyl-1,3-pentanediol diisobutyrate와 쓴냄새 성분인 ${\beta}$-selinene, ledene, isoledene, ${\delta}$-cadinene 및 나무 냄새를 갖는 ${\alpha}$-humulene, dihydro-${\beta}$-agarofuran 등도 식품의 향기와 관련이 있는 것들이다. 이에 반해 풋냄새와 관련 있는 성분들 즉, 1-hexanol, 2-methylhexan-3-ol, 3-hexen-1-ol, cis-3-hexenyl butyrate, ethylhexanol, hexyl acetate, trans-2-hexen-1-ol이나 camphor, longiborneol, menthol 등 장뇌냄새의 원인 물질은 함유량이 상대적으로 적은데도 불구하고 전문조향사들은 신선 더덕의 특징적인 향기로 풋냄새와 장뇌취를 선정하였다. 따라서 유통업자를 중심으로 향기 특성 및 강도를 판정할 수 있는 훈련이이루어진다면 향기는 더덕의 신선도를 판정하는 지표로 활용될 수 있다고 생각된다.