• 월간산업보건
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• s.269
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• pp.11-13
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• 2010

• The Korean Journal of Food And Nutrition
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• v.11 no.3
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• pp.272-277
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• 1998

We carried out separation and guantitation of flavor components by GC about essential oils extracted from deodorized corn oil at the different deodorizing temperature. Flavor components were detected total 16 kinds included aldehydes of 8 kinds, major components were propane, pentane, hexanal etc. These major components content was about 70~75% of the total flavor components. According to rise of deodorizing temperature, both ethane and aldehydes of 8 kinds content were in proportion to increase, but propane, pentane, hexane, octan, pentyl furan content were decreased by contraries, respectively. On the other hand, total flavor component content was appeared the lowest level at 245$^{\circ}C$ treating group, aldehydes content was in proportion to increase according to rise of deodorizing temperature. These phenomenons consider that the undesirable reactions such as partial auto-oxidation, degradation, polymerization and hydrolysis etc. by effecting factors of stripping steam and vacuum degree. Conclusively, deodorizing temperature under high temperature was undesirable for the minimization of off-flavor materials.

• Journal of the Korean Society of Food Culture
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• v.20 no.2
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• pp.214-220
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• 2005

Seasoning oil (SO) for Chinese dish was manufactured from the combination of Maillard reaction for methionine and xylose with autoclaving method. Volatile compounds were determined by GC, GC-MSD for this SO and 3 kinds of seasoning jajang samples which was obtained from restaurant. From this SO 61 kinds-404.92ppm volatile compounds were separated and identified. And from 3 samples of restaurant, 39 kinds-333.52ppm, 42 kinds-330.01ppm, 42 kinds-393.18ppm obtained respectively. Major volatile components of SO were diallyl disulfide, pentane, diallyl trisulfide, t,t-2,4-decadienal and zinngiberene. Those contents were 40.15ppm, 32.32ppm, 19.57ppm, 15.06ppm and 13.23ppm, respectively. Major volatile components in 3 kinds samples were pentane, propenal, hexanal, t-2-heptanal, 2,4-heptadienal, t,t-2,4-decadienal and unknown components. The volatile components of SO were very similar to 3 samples,

• Applied Chemistry for Engineering
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• v.4 no.3
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• pp.515-521
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• 1993

Separation of deasphalted oil from atmospheric residue using n-pentane as a solvent was carried out to obtain the valuable heavy hydrocarbon products that can be used lube base oil. After separation experiments, it is shown that the separation yield of oil from atmospheric residue was dependent on n-pentane density and increased in the critical region of n-pentane. Also, the metal content of separated oil was much lowered when compared with that of atmospheric residue. However, there's slight differences in sulfur removal between above two cases.

• Korean Chemical Engineering Research
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• v.60 no.4
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• pp.544-549
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• 2022

This study presents the negative pressure cavitation acetone-pentane fractional precipitation to dramatically improve the precipitation efficiency of paclitaxel from Taxus chinensis. When paclitaxel was precipitated under a negative pressure of -200 mmHg, most paclitaxel (>99.9%) could be recovered in a short precipitation time (5 min). The precipitation rate constant increased by 1.512~5.073 times (at -50 mmHg to -200 mmHg) compared to the control. The activation energy decreased by -3,737~-6,536 J/mol due to negative pressure, which increased the precipitation rate. With the introduction of negative pressure, the precipitate size decreased by 5.3 times, and the diffusion coefficient of paclitaxel increased by 7.0 times.

• 월간산업보건
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• s.282
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• pp.28-30
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• 2011

• Progress in Medical Physics
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• v.8 no.2
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• pp.77-85
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• 1997

Verification of patients setup was very important during radiotherapy. Therefore, we have developed an 1-dimensional on-line portal imaging system and measured the differential linearity of the system. Isooctane(2,2,4-TetraMethyl Pentane) was used as liquid ionization material. And the geometry of the system was designed which has 2mm position resolution and 20cm measurable range. And then the differential linearity of the system was 4.7％.

• Applied Chemistry for Engineering
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• v.5 no.1
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• pp.105-113
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• 1994

The amount of nitrogen gas adsorbed by Spherocarb and Sucrose Char was measured as a function of the relative pressure with temperature being kept constant at 77 to 184K. Isotherms at different temperatures were obtained by keeping the adsorbent at a constant temperature using liquid nitrogen, iso-pentane, n-pentane, ethyl alcohol, and iso-propyl alcohol slush baths. The objective for this study is to provide information on the specific surface area and pore volume by analyzing the experimental data using adsorption models such as the Brunauer-Emmett-Teller and Dubinin-Radushkevich models.

• Proceedings of the Korean Society of Postharvest Science and Technology of Agricultural Products Conference
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• 2003.10a
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• pp.149.2-149
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• 2003

비조사 김치와 2.5, 5 및 10 kGy로 방사선 조사된 김치로부터 SDE 방법으로 추출한 휘발성 유기화합물을 분석하여 변화를 확인하였다. 김치의 주요 휘발성 유기화합물로 ethyl formate, ethyl acetate, ethanol, dimethyl disulfide, methyl 2-propenyl disulfide가 다량 함유되어 있었고, ethyl methyl disulfide, 4-cyano-1-butene, pentane dinitrile 등도 상당량 함유되어 있었다. Ethyl formate, ethyl acetate, ethanol은 조사선량이 증가함에 따라 상당량 증가하는 것으로 확인되었으며, dimethyl disulfide, ethyl methyl disulfide, methyl propyl disulfide, pentane dinitrile, S-methyl methyl thiosulfonate 등도 선량이 증가함에 따라 함량이 증가하였다. 1-Penten-3-ol은 조사선량에 따라 감소하였다.

• Journal of the Korean Applied Science and Technology
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• v.16 no.2
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• pp.179-185
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• 1999

The effect of blowing agents and inner temperature on the machanical properties of the flexible polyurethane foams were investigated. In the study used that chemical blowing agents is $H_2O$ and support blowing agents. CFC-11, HCFC-114b, dichloromethane, n-penthane, iso-pentane, cyclopentane. The flexible polyurethane foams were foamed by the density of $0.015{\pm}0.002g/cm^3$ and $0.024{\pm}0.002g/cm^3$ which were used in mechanical properties measurements. Inner temperature was measure as long as the preparation of the flexible polyurethane foams of each blowing agents. The density, tensile strength, elongation, tear strength, compression strength and compression set were measured after 48 hours hardening. The result of the study was optimized dichloromethane and cyclopentane at the support blowing agents.