• Food Science and Biotechnology
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• 제18권6호
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• pp.1392-1397
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• 2009

This study was aimed at developing a low cost cold storage system for agricultural products. Three kinds of slurries: $K_1$, $K_2$, and $K_3$ slurries were developed using phase change materials (PCMs) such as tetradecane, octadecane, and sodium polyacrylate to maintain the desired temperature ranges. The slurries were manufactured by in-situ polymerization. Tetradecane and octadecane were capsulated in a core with melamine at the surface. The thermodynamic characteristics of the slurries were measured and analyzed. The latent heats of the $K_1$, $K_2$, and $K_3$ slurries at the melting points were 206.41, 186.88, and 147.91 kJ/kg, respectively. A transportable cold storage container was built to investigate the performance of the slurries as thermal storage media. The temperatures at the insides of the container could be maintained in the ranges of 0-5, 5-10, and $10-15^{\circ}C$ for more than 23, 27, and 60 hr with the $K_1$, $K_2$, and $K_3$ slurries, respectively.

• 한국응용과학기술학회지
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• 제18권4호
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• pp.273-284
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• 2001

A series of microcapsule were synthesized by using several PCM(Phase Change Material) as a core material and gelatin/arabic gum, melamine/formaldehyde as a shell material. Coacervation technique and in situ polymerization were adopted in synthesizing microcapsules. In the microencapsulation by coacervation, tetradecane and octadecane were used as core materials. In the microencapsulation by situ polymerization tetradecane, pentadecane, hexadecane, heptadecane, octadecane, and nonadecane were used as core material. The synthesized microcapsule was examined to observe the shape of the microcapsule. The particle size analysis was performed by particle size analyzer. The thermal properties(e.g. melting point, heat of melting, crystallization temperature, heat of crystallization, differences between melting point and crystallization temperature) were obtained by DSC(Differential Scanning Calorimeter). The stirring rate effect was investigated during the microencapsulation. It was found that with increasing the stirring rate much smaller microcapule was produced. However, this did not necessarily lead to formation of spherical microcapsule.

• 대한화학회지
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• 제42권5호
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• pp.565-569
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• 1998

• 한국섬유공학회:학술대회논문집
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• 한국섬유공학회 2002년도 봄 학술발표회 논문집
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• pp.285-288
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• 2002

옥타데칸[$CH_3$[C $H_2$]$_{l6}$$CH_3$]은 상전이 물질(phase change material)이며, 상전이 물질은 상변화를 통해 주변의 온도가 상승하면 녹으면서 열을 흡수하고, 주변의 온도가 낮아지면 결정화(crystallization)하면서 열을 방출하는 축열ㆍ방열성을 반복적으로 나타내는 에너지 물질(enthalpic substance)이다[1, 2]. 옥타데칸은 메탄계열 탄화수소로서 파라핀류(paraffins)에 해당된다. (중략)략)

• 한국섬유공학회:학술대회논문집
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• 한국섬유공학회 2003년도 가을 학술발표회 논문집
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• pp.92-95
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• 2003

스포츠웨어는 착용 중의 쾌적함을 위하여 자연환경의 변화, 인체의 운동 및 활동 상황에 맞추어 그 기능을 적절히 조절할 수 있어야 한다. 인체는 체온 조절을 위해 땀을 흘리고 이 땀이 의복 밖으로 원활히 방출되지 못하면 덥고 습한 온열 생리적 불쾌감이 유발된다. 그러므로 온열적 불쾌감을 발생시키지 않도록 하는 것이 스포츠웨어가 가져야 할 중요한 기능이다. 이러한 환경 및 인체변화에 대응하여 투습ㆍ발수 소재가 일상 스포츠 웨어의 소재로 널리 쓰이고 있다. (중략)

• 한국염색가공학회:학술대회논문집
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• 한국염색가공학회 2007년도 추계학술발표회
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• pp.141-142
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• 2007

• 한국미생물·생명공학회지
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• 제6권4호
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• pp.173-179
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• 1978

1) 고온성으로 탄화수소를 자화할 수 있는 균체를 생산하는 목적으로 90여점의 시료로부터 세 균주의 효모를 선별하여 다음의 결과를 얻었다. 2) 선정된 세 균주 효모의 최적생육온도는 4$0^{\circ}C$~45$^{\circ}C$였과. 그리고 이들은 각각 Candida tropicalis (strain A-28), Torulopsis molisichiana (strain B-8) 그리고 Candide krusei (strain C-15)로 각각 동정되었다. 3) 특히 균주 A-28은 tetradecane, hexadecane 과 octadecane을 다같이 쉽게 자화하였고 B-8과 C-15 균주는 다른 n-paraffin 보다 hexadecane을 잘 자화하였다. 4) 선정된 세 균주효모의 세대시간은 3.4.~4.0 시간, 비증식속도는 0.170~0.215이고 그리고 균체수율은 86~98%이였다. 5) 이들 균체의 조단백질은 48.2~61.5%, 지방은 3.7~8.0%, 조섬유는 3.5~4.2%, 회분은 5.6~6.7%, 무질소가용성 물질은 23.5~31.8%였고, thiamine은 0.28~0.93 mg%, riboflavin 6.03~7.3 mg%이었다. 6) 균체단백질의 아미노산조성은 비교적 골고루 함유되었다. 그러나 함황(sulfur containing) amino acid는 극히 적었다.

• 한국환경과학회지
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• 제23권7호
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• pp.1253-1268
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• 2014

This study was investigated twenty two hazardous chemicals compounds for effluents of nine sewage treatment plants (STPs) and one waste water treatment plant (WWTP) in the Nakdong Ri-ver Basin. They are eleven phthalates(DMP, DEP, DIBP, DBP, BEEP, DNPP, DHP, DCP, DEHP, DNOP, Dinonyl phthalate, seven aliphatic hydrocarbons(n-Tridecane, n-Tetradecane, n-Pentadecan-e, n-Hexadecane, n-Heptadecane, n-Octadecane, n-Nonadecane, Isoquinoline, 2-Chloropyridine, 2-N-itrophenol, and Benzophenone. The twenty two compounds were analyzed by gas chromatograp-hy mass spectrometry (GC/MS) with liquid-liquid extraction (LLE). Twenteen of twenty two subs-tances were detected. They were DMP, DEP, DIBP, DBP, DEHP, n-Tetradecane, n-Pentadecane, n-Heptadecane, n-Octadecane, n-Nonadecane, Isoquinoline and Benzophenone. Among these, DEHP, DEP and Benzophenone were most frequently observed. They were obtained as $ND{\sim}36.881{\mu}g/L$, $ND{\sim}0.950{\mu}g/L$, $ND{\sim}2.019{\mu}g/L$, respectively. When the substances were calculated the average concentration at 10 points, the maximum average detection concentration was investigated at the Dalseocheon STP.

• Fibers and Polymers
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• 제6권4호
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• pp.343-347
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• 2005

The purpose of this study was to investigate the appropriate amounts of phase change materials to give objective and subjective wear sensations. Vapor-permeable water-repellent fabrics with (WR-PCM) and without (WR) octadecane containing microcapsules were obtained by wet-porous coating process. Then, calculating the area of the WR-PCM treated clothes, we estimated the total calories of the clothing by multiplying the heat of fusion and heat of crystallization of PCM to the calculated area. Wear tests were conducted in both warm environment $(30^{\circ}C,\;65\%\;RH)$ and cold environment $(5^{\circ}C,\;65\%\;RH)$ with sports warm up style experimental garments made with WR and WR-PCM fabrics. Rectal, skin, and clothing microclimate temperatures, saliva and subjective evaluation measurements were done during the wear test. There was no difference of rectal and mean skin temperatures between WR and WR-PCM, but the clothing microclimate temperature of WR-PCM under warm environment was slightly lower than that of WR. In cold environment, WR-PCM showed much higher temperature than in WR. Saliva change did not appear between clothes, but did between two environments. Although subjective sensation between WR and WR-PCM was not significantly different, WR-PCM was rated as cooler than WR in warm environment and as warmer than WR in cold environment. The results of this study indicated that octadecane containing microcapsules in water-repellent fabric provide cooling effect.

• Bulletin of the Korean Chemical Society
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• 제11권3호
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• pp.206-208
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• 1990

Cu(II) hexaazamacrotricyclic complexes $[Cu(L)](ClO_4)_2$ and $[(Cu(L)Cl]ClO_4$, where L = 1,3,6,9,11,14-hexaazatricyclo$[12.2.1.1^{6,9}]octadecane(L_1)$ or 1,3,6,10,12,15-hexaazatricyclo$[13.3.1.1^{6,10}]eicosane(L_2)$, have been prepared by the simple template condensation reactions of triamines, diethylenetriamine for $L_1$, and N-(2-aminoethyl)-1,3-propanediamine for $L_2$, with formaldehyde in the presence of $Cu(OAc)_2\;or\;CuCl_2$. The Cu(II) complexes of $L_1$ contain two 1,3-diazacyclopentane ring moieties and those of $L_2$ contain two 1,3-diazacyclohexane ring moieties that are fused to the 14-membered macrocyclic framework. Spectra indicate that complexes $[Cu(L)](ClO_4)_2\;and\;[Cu(L)Cl]ClO_4$ have square-planar and square-pyramidal chromophores, respectively. square-planar $[Cu(L)](ClO_4)_2$ are remarkably stable against ligand dissociation in acidic aqueous solutions. Square-pyramidal $[Cu(L)Cl]ClO_4$ complexes dissociate their axial Cl-ligands easily in aqueous solutions to form $[Cu(L)H_2O]^{2+}$ species. Infrared and UV/vis absorption spectra of the Cu(II) complexes reveal that Cu-N interactions and the ligand field strengths are significantly weaker in the complexes of $L_2$ than in the complexes of $L_1$.