• 한국안전학회지
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• 제20권2호
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• pp.44-49
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• 2005

Real-scale experimental study was performed to characterize the surface flame propagating velocity along the OF cable in the underground utility fire. Temperatures of oil filled OF cable and dried OF cable with the diameter of 90mn were measured using thermocouple and data log system. The hexane and alkyl-benzene oil were used as a fire source using the ignition device. As a result while the surface flame propagating velocity of the three cables was $0.06\~0.09cm/s$, the surface flame propagating velocity of the one cable was $0.028\~0.032cm/s$. Therefore, it was found that the surface propagating flame velocity of the three OF cables is $2.1\~2.8times$ faster than that of one OF cable case. The results show that the surface propagating flame velocity became larger as increase of the number of cable, the volume of alkyl-benzene oil in the cable. The characteristics of surface propagating flame velocity in the OF cable can be helpful to fire suppression system in utility.

• Mass Spectrometry Letters
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• 제3권2호
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• pp.43-46
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• 2012

In this study, comprehensive two dimension gas chromatography (2D GC-MS) and 15 T Fourier transform ion cyclotron resonance mass spectrometry (15T FT-ICR MS) connected to atmospheric pressure photo ionization (APPI) have been combined to obtain detailed chemical composition of a diesel oil sample. With 2D GC-MS, compounds with aliphatic alkyl, saturated cyclic ring(s), and one aromatic ring structures were mainly identified. Sensitivity toward aromatic compounds with more than two aromatic rings was low with 2D GC-MS. In contrast, aromatic compounds containing up to four benzene rings were identified by APPI FT-ICR MS. Relatively smaller abundance of cyclic ring compounds were found but no aliphatic alkyl compounds were observed by APPI FT-ICR MS. The data presented in this study clearly shows that 2D GC-MS and 15T FT-ICR MS provides different aspect of an oil sample and hence they have to be considered as complementary techniques to each other for more complete understanding of oil samples.

• 분석과학
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• 제9권2호
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• pp.168-178
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• 1996

근적외선과 $^{13}C$-핵자기 공명 분광학에 의한 석유유분(경유, 벙커-C유, 윤활기유)의 분자구조를 조성(방향족, 나프텐, 파라핀), 방향족(벤젠-핵과 결합된 알킬기), C2(메틸렌) 탄소원자 %, 알킬기 내에서의 $C_{\alpha}$ 와 $C_{\beta}$탄소원자 %, 그리고 파라핀(가지형, 직선형)으로 세분화하여 분석, 비교 하였다.

• 설비공학논문집
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• 제16권2호
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• pp.150-157
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• 2004

Carbon dioxide ($CO_2$, R-744) has become a very popular issue in application to refrigeration and air conditioning systems as a natural refrigerant. An experimental study has been carried out to investigate miscibility and the vapor pressure of refrigerant R-744 in the presence of lubricant oil. This is of particular interest in the selection of the lubricant oil for the compressor of a refrigeration system or an air conditioning system using the refrigerant R-744. The experimental set-up consists of the equilibrium cell, measuring devices, the vacuum pump, the constant temperature bath and relevant connecting pipes made of stainless steel. Five lubricant oils, such as mineral oil (Naphthenic), AB (Alkyl Benzene) oil, PAO (Poly Alpha Olefin) oil, PAG (Poly Alkylene Glycol) oil and POE (Polyol Ester) oil are considered in the present study. Test runs were conducted with the oil concentration range from 5 to 50 wt％, and the temperature range from -10 to 1$0^{\circ}C$ with 2$^{\circ}C$ intervals. The miscibility results are visualized and correlated with the vapor pressure for the individual test components.

• 대한화학회지
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• 제19권1호
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• pp.50-52
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• 1975

潤滑再生油의 酸化安定性이 向上되는 機構를 알기 爲하여 第一報에서 만든 試料와 輕油을 混合한 것과 輕油에다 添加劑(알킬벤젠과 페놀형물질)를 混合한 試料의 酸化安定性能 試驗을 하여 內然機關에서 使用한 潤滑廢油의 再生油가 酸化安定性이 向上되었음을 알았고 使用途中 芳香族化合物, 特히 페놀型 有機物의 生成에 基因한다는 結論을 얻었다.

• 공업화학
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• 제31권4호
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• pp.429-437
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• 2020

본 연구에서는 이소소르비드를 이용하여 양이온 제미니 계면활성제의 알킬기가 C₁₀~C₁₆개로 변화시키면서 합성하였다. 합성한 양이온 제미니 계면활성제에 대한 c.m.c는 5.13 × 10^-4~1.62 × 10^-4 mol/L의 범위에서 표면장력은 31.86~39.24 dyne/cm로 측정되었으며, 알킬기의 길이가 길어질수록 표면장력이 상승하였다. 또한, 흡착량는 감소하여 계면에 흡착된 계면활성제의 분자 당 차지하는 면적이 커지게 되면서 공기-물 계면에 기포력이 감소하였다. 벤젠에서의 유화력은 8 h이 지난 후 60 ± 5% 이상의 유화력이 유지되었으며, 대두유에서의 유화력이 50 ± 5% 이상 감소하는 경향을 보였다. 소수성이 강한 벤젠에서 우수하며, 유상과 수상의 프리에멀젼 제조 시, 유화 안정성이 일정한 시간 이상 유지되는 것을 확인할 수 있었다. 항균력은 Escherichia coli (E.coli)과 Staphylococcus aureus에서의 clean zone의 크기가 증가하여 합성한 양이온 제미니 계면활성제의 소수성 사슬의 길이에 의존하였다.

• 공업화학
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• 제5권1호
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• pp.99-104
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• 1994

비이온성 계면활성제인 5종의 모노글리세릴 기로글루타메이트류는 초산나트륨 촉매하에 피로글루탐산과 모노글리세리드를 에스테르 반응시켜 높은 수율로 제조하였다. IR, $^1H-NMR$로 그들의 구조를 확인하였고 계면장력, 유화력을 측정하였다. 반응 생성물들의 오일용액에서의 물에 대한 계면장력은 5~9dyne/cm까지 저하되었고, 계면장력 저하능은 모노글리세리드 퍼로글루탐산 에스테르의 소수성 탄소부에 의존된다. 벤젠 및 대두유에서의 유화력을 측정한 결과 대두유보다 벤젠의 유화력이 우수하였으며 유화제로서의 응용이 기대된다.

• 한국응용과학기술학회지
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• 제15권2호
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• pp.77-81
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• 1998

Surface active properties of these aqueous Gemini surfactant solutions including surface tension, critical micelle concentration(cmc), foaming power, foam stability, emulsifying power and Krafft point were measured at given conditions. They showed excellent properties, being compared with conventional single-chain surfactants such as sodium dodecyl sulfonate(SDS). Their surface tensions in the aqueous solutions were decreased to $30{\sim}38$ mN/m, which is lower than 39 mN/m of SDS, and their cmc values evaluated by surface tension method were $2.8{\times}10^{-5}{\sim}3.3{\times}10^{-4}$ mol/L. These values were also much lower than that of SDS, $9.8{\times}10^{-3}$ mol/L. The foaming power and foam stability, especially decyl and dodecyl compounds, were good and the emulsifying power in benzene or soybean oil was also excellent. All of the synthesized Gemini surfactants possessed good water solubility and their Krafft points were all below $0^{\circ}C$. As results, DDED and DDOD, Gemini surfactants which were synthesized are expected to be applied as foamers, emulsifiers and so on.

• 한국응용과학기술학회지
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• 제15권2호
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• pp.11-24
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• 1998

All the surface activities including surface tension, foaming power, foam stability, emulsifying power, dispersion effect, and detergency were measured and critical micelle concentration(cmc) was evaluated in dilute aqueous solution. The cmc evaluated by the Ring method was $10^{-3}{\sim}10^{-4}mol/L$ in case of monoesters, and $10^{-3}{\sim}5.0{\times}10^{-5}mol/L$ in case of diesters, respectively. Surface tension of the aqueous solution was decreased to $45{\sim}50dyne/cm$, showing the tendency that the ability of lowering the surface tension was dependent on increasing of carbon atom number in alkyl chain. Foaming power of all the monoesters was better than that of diesters. while foam stability of diesters was to the contrary. Emulsifying power of soybean oil or benzene was specially expected to be good for emulsifiers in industrial application fields. HLB values of monoesters and diesters evaluated by Griffin's method were in the range of 8 to 12. Dispersion property of ferric oxide was stable in the range of $4.5{\times}10^{-5}{\sim}5.0{\times}^{-4}mol/L$ in case of monoesters, and $10^{-5}{\sim}10^{-4}mol/L$ in case of diesters.