• Korean Journal of Food Science and Technology
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• v.32 no.1
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• pp.42-49
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• 2000

A new method for the quantitative determination of capsaicinoids in microcapsule has been developed. Among seventeen solvents tested for solubilizing wall material (gum arabic and modified starch) of microcapsule, dimethyl sulfoxide (DMSO) was selected as an optimal solvent. The most appropriate mixing ratio of microcapsule to DMSO for solubilizing wall material was 1 to 10(w/v). Appropriate carriersolubilizing temperature and time were $55^{\circ}C$ and 30 min, respectively. Also conditions for extracting oleoresin from the solubilized microcapsule were studied. The mixing ratio of ethanol to DMSO was optimal at 8 to 1(v/v). Optimized vortexing time was 5 min at 40㎐. Pecipitant was obtained by centrifugation at 21000 rpm for 15 min. The precipitant was reextracted with ethanol. The extracted supernatants were combined and adjusted to final volume of 25 ml. Extracted solutions were analyzed for quantitation of total capsaicinoids by employing HPLC and for quantitation of total carotenoids by spectrophotometric method. This method can be used to monitor changes of capsacinoid during manufacturing or storage of red pepper oleoresin microcapsule powder.

• Journal of Energy Engineering
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• v.17 no.1
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• pp.38-45
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• 2008

In this work, we investigated the variation of physical and chemical characteristics of solvent-insolubles and solvent-solubles in Canada's Athabasca oil sands by solvent-insolubles experiments. N-Heptane, n-Hexane, and n-Pentane were tested for solvents and asphaltenes were separated from maltenes by using a modified ASTM D 3279 method. Elemental analysis, boiling point distribution (SIMDIS), molecular weight distribution, heavy metal contents, API gravity, viscosity and SARA fractions were measured for thorough samples. The asphaltenes-removed maltenes contained less sulfur and heavy metal amounts and had lower molecular weight than the original bitumen. N-Pentane solvent could lower sulfur and heavy metal amounts, molecular weight, and viscosity of maltenes compared to the other solvents. Eventually, we confirmed that the obtained experimental data could be used as basic informations of bitumen upgrading processes for the production of SCO (synthetic crude oil).

• Elastomers and Composites
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• v.34 no.3
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• pp.239-246
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• 1999

Side wall samples from a used automotive tire were subjected to subcritical and supercritical decomposition and extraction with three solvents, water, 28% ammonia solution and ammonia. For 6mm cube samples the rate of supercritical extraction with water followed a first-order kinetics with an activation energy of 140 kJ/mol. Solvent power of 28% ammonia so lotion at supercritical condition was found to be higher than supercritical water at initial extraction as pressure decreased. These phenomena were considered to be an effect of ammonia involved in water.

• Journal of the Korean Chemical Society
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• v.41 no.2
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• pp.63-68
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• 1997

Calorimetric measurements have been carried out for the binary mixture between protic, ROH (R=Me, Et) and dipolar aprotic solvents, MeCN,$Me_2CO,\;MeNO_2(or EtNO_2)$in order to investigate the molecular interaction and liquid structure of isodielectric solvents. From the measured partial molar enthalpies of the solutions, excess enthalpies for the mixing process were determined. The hydrogen bond strength between two components decreases in the order of$ROH-ROH>ROH-Me_2CO>ROH-MeCN>ROH-MeNO_2(or EtNO_2)$and the hydrogen bond donor acidity decreases in the order of MeOH>EtOH. From this result, we can conclude that the most important interaction for the formation of binary liquid mixture comes from the specific hydrogen bond.

• 월간산업보건
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• s.90
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• pp.2-8
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• 1995

원자 흡수 분광법과 용매 추출을 이용한 크롬의 정량분석 조건을 연구하였다. tertiary amine류 중 octy기를 갖는 trioctylamine(TOA)과 quaternary ammonium salt류 중 octy1 기를 갖는 trioctylmethylammonium chloride(TOMAC)가 음이온 교환기로 사용되었다. 또한 첨가되는 산의 종류와 산의 농도 변화에 따라서 원자흡수분광기를 이용하여 흡광도를 측정하였다. TOA사용시 염산의 농도가 0.1M-0.3M사이, TOMAC사용시 염산의 농도가 0.03M-0.1M사이에서 최대 흡광도를 나타내었다. 산이 첨가된 MIRK에 용해된 TOA나 TOMAC와 Cr과의 mole농도 비율이 1:1이상이 된 것이 최대 추출효율을 보았다. 추출과정을 검토한 결과, 본 실험에서 사용된 방법은 비슷한 다른 방법들과 비교하여 보면 크롬의 추출효율이 좋은 것으로 판명되었다.

• Applied Chemistry for Engineering
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• v.10 no.4
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• pp.581-585
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• 1999

The surface treated hydroxypropyl methylcellulose(HPMC) which could adjust the soluble time was synthesized when 40 wt % glyoxal solution and $KH_2PO_4$ were sprayed and reacted. And also, the solution dynamic at different ratios of two adding agents were identified If the surface of HPMC was treated with only glyoxal, the dispersion characteristics at different ratios of two adding agents were identified If the surface of HPMC was treated with only glyoxal, the dispersion was observed in the neutral solution and the viscosity was increased after directly dissolved as the solution become alkali condition. But the fine-powder type of HPMC which reacted with glyoxal and $KH_2PO_4$ was dispersed regardless of pH of solution and observed that it was dissolved and its viscosity increased after elapsing some time. With increasing amount of glyoxal and $KH_2PO_4$, the soluble time was delayed. The reaction condition was about 60 min at $75{\sim}85^{\circ}C$. Especially, the removal process of organic solvent after reaction was not required due to reaction under water solution without organic during glyoxal and $KH_2PO_4$ treatment. And also, the HPMC which could adjust the soluble rate in water or organic solvent by changing the degree of substitution of HPMC was synthesized.

• Journal of Life Science
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• v.12 no.5
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• pp.584-588
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• 2002

Asymmetric enantioselective resolution system using epoxide hydrolase activity of Aspergillus niger LK was developed and operated for the production of optically pure styrene oxide. Two-phase hollow-fiber reactor system was employed for the enhanced solubility of racemic styrene oxide in organic phase and protection of epoxide hydrolase activity in aqueous phase. For the removal of phenyl-1,2-ethandiol, the inhibitor of epoxide hydrolase, cascade hollow-fiber reactor system was also developed. Chiral (S)-styrene oxide (39 mM in dodecane) could be asymmetrically resolved with high enantiopurity (> 99% ee) using these reactor system.

• KSBB Journal
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• v.5 no.3
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• pp.215-221
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• 1990

The solubilization of BSA, pepsin, trypsin and ribonuclease-a in cationic reverse micellar solutions has been investigated. For complete solubilization into reverse micellar solutions, pH values of several pH units above the isoelectric point of each protein were required. Solubilization was observed to decrease with increasing ionic strength of KCI. The size of empty micelles showed no significant change with increasing ionic strength. Trioctylmethyl ammonium chloride (TOMAC) in cyolohexane showed the lowest solubilization for the proteins. The system didodecyl dimethyl ammonium bromide (DDAB)-tetrachloroethylene was capable of solubilizing larger amounts of proteins than the system DDAB-benzene. Cetyl trimethyl ammonium bromide(CTAB)-hexanol-isooctane system showed lower solubilization than DDAB-tetrachloroethylene system, while it had higher Wo value.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.21 no.1
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• pp.19-37
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• 1995

A fine oil -in-water (O/W) emulsion using non-aqueous emulsification technique was developed. And the behaviors of POE(25)octyldodecyl ether in non-aqueous polyol/oil systems were studied by observing the surface tension, interfacial tension, turbidity and transition temperature. It was found that POE(25)octyldodecy1 ether hardly existed as the micelle in the non-aqueous polyol system while, in water, it formed micelles very easily. So, when a polyol, like glycerine in which POE(25)octyldodecyl ether has a poor solubility, was added, POE(25)octyldodecyl ether moved to the surface. After saturated at surface, POE(25)octyldodecyl ether began to precitate. The mean particle size of the final emulsion was 230nm. Also, the emulsion system was stable at 0$^{\circ}C$, 25$^{\circ}C$, 40$^{\circ}C$, 50 $^{\circ}C$ and freeze-thaw cycle chamber for a month, while a conventional emulsion system was unstable. It is concluded that, by pertinent combination of polyols, we can improve the adsorption efficiency of surfactant.

• Journal of the Korean Society of Food Science and Nutrition
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• v.46 no.5
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• pp.616-621
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• 2017

The objective of this study was to investigate the physicochemical properties of domestic strong wheat flour (DSWF). Three commercial DSWFs (D1, D2, and D3) were compared with imported strong wheat flour (ISWF). DSWFs had higher moisture content, crude protein content, lightness, and whiteness than ISWF. DSWFs showed lower solvent retention capacity and water absorption index than ISWF. DSWFs also showed significantly higher water solubility index than ISWF (P<0.05). Setback values by rapid visco analysis were significantly higher in D1 and D2 than in ISWF and D3, which means ISWF and D3 were better in retarding retrogradation. Differential scanning calorimetry results showed that ISWF required 6.2 J/g of energy for phase transition, whereas DSWFs needed 6.67~7.13 J/g. The farinograph results showed that ISWF had higher water absorption, longer dough stability time, and significantly higher softening of dough at 20 min than DSWF (P<0.05). Dough resistance and extensibility were higher in ISWF than in DSWFs.