• Food Science and Preservation
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• v.30 no.3
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• pp.492-501
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• 2023

In this study, we wanted to understand the impact of different decaffeination processes on aroma compounds of coffee. Therefore, we analyzed differences in physical characteristics and volatile aroma compounds profiles of regular coffee (RC), Swiss water process decaffeinated coffee (SWDC), and supercritical CO₂ decaffeinated coffee (SCDC) after roasting the coffee beans. The electronic nose analysis identified RC and SCDC as different groups which indicates that these groups volatile aroma compound compositions were different. The principal component analysis of volatile compound patterns identified using an electronic nose indicated that there was a large difference in volatile compounds between RC, which was not decaffeinated, and both decaffeinated SWDC and SCDC. The major aroma compounds of RC, SWDC and SCDC were propan-2-one and hexan-2-one which are ketone, and hexanal and (E)-2-pentenal which are aldehyde and 3-methyl-1-butanol which is an alcohol. After roasting, the composition of major volatile compounds appearing in the beans was similar, but the relative odor intensity was different. We identified 28 volatile aroma compounds from RC, SWDC, and SCDC using headspace-solid phase microextraction-gas chromatography/mass spectrometry (HS-SPME-GC/MS), and analyzed 10 major compounds that were present in high abundance, including furfural, 2-furanmethanol, 2,5-dimethylpyrazine, and 2-ethyl-3-methylpyrazine.

• Journal of the Korean Ceramic Society
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• v.25 no.5
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• pp.425-430
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• 1988

In this study, aluminum sec-butoxide, aluminum iso-propoxide were mixed with alcohol such as, secbutanol, iso-propanol. And then Acetyl Acetone, water were added to make Acetyl bond and OH bond. After that, Polymeric alumina sol was synthesized from catalysis reaction with strong acid typically HCl. These alumina soil was dried at 8$0^{\circ}C$~9$0^{\circ}C$ to have a optmum viscosty for spinning, spinned at spinner, and then sintered to make polycrystalline alumina fiber.

• Proceedings of the Korea Environmental Mutagen Society Conference
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• 2003.05a
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• pp.54-54
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• 2003

• Proceedings of the Korean Institute of Industrial Safety Conference
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• 2002.11a
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• pp.178-183
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• 2002

화학공정설계에 있어 온도, 압력, 농도 등에 대한 운전 범위와 반응물, 중간생성물, 생성물 및 부산물에 대한 물성치인 물리적 및 화학적 특성, 안전성, 독성 등을 파악하는 것이 무엇 보다 중요하다. 공정상에서 가연성물질의 생산, 처리, 수송, 저장할 때 취급 부주의로 화재 및 폭발이 야기될 수 있다. 따라서 가연성물질의 안전한 취급을 위해서는 이들 물질의 중요한 기초적인 안전특성(safety property) 자료인 인화점(flash point)에 대한 지식을 필요로 한다.(중략)

• Bulletin of the Korean Chemical Society
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• v.33 no.12
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• pp.4231-4234
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• 2012

• Archives of Pharmacal Research
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• v.3 no.2
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• pp.87-88
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• 1980

The goal of this research is to provide information that will lead to the development of new non-phototoxic antimalarial compounds. The goal was approached by first learning the chemical mechanism of phototoxicity of six representative compounds 1a-f: a[(diethyl-, -dihexyl-, and -dioctyl- aminomethyl)]-2-(3', 4' -dichlorophenyl)-6-methoxy-4-quinolinemethanol (1a, 1b, and 1c) and .alpha. [(diethyl-, -dibutyl-, and -dihexyl-aminomethyl)]-2-(-4'-methoxyphenyl-6-methoxy-7-chloro-4-quinolinemethan ol (1d, 1e, and 1f). The photochemical reaction of these compounds was investigated in 2-propanol. Similar photochemical fragmentation reactions accurred in all compounds.

• 한국생물공학회:학술대회논문집
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• 2000.11a
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• pp.45-46
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• 2000

After cell removal from fermentation broth the supernatant containing poly (${\gamma}-glutamic acid$) (${\gamma}-PGA$) was concentrated by ultrafiltration in order to reduce the amount of organic solvents such as methanol, ethanol, propanol required for the recover of ${\gamma}-PGA$ with precipitation. The concentration and volume reduction of cell-free solution by ultrafiltration could reduce 3 times the amount of ethanol for the recover of ${\gamma}-PGA$ from cell-free fermentation broth.

• Journal of the korean Society of Automotive Engineers
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• v.13 no.3
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• pp.43-48
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• 1991

Activation energies of alcohol fuels have been determined through droplet combustion and extinction experiments using droplet suspension technique in a low pressure environment to minimize the effect of buoyance. Results show that the activation energies determined are 41.4 kcal/mol for ethanol, 47.6 for 1-propanol, 48.4 for 1-butanol, 40.0 for 2-butanol, 48.0 for 1- pentanol, 50.8 for 1-hexanol and 51.7 for 1-decanol.

• International Journal of Safety
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• v.10 no.1
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• pp.5-9
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• 2011

Two popular activity coefficient models, Wilson and NRTL equations have been used to correlate the published flash point data on the n-propanol + propionic acid and n-butanol + propionic acid systems through the optimization method. The results of these correlation were compared with the results calculated by Raoult's law. The optimization method were found to be better than those based on the Raoult's law. The optimization method based on the Wilson equation described the published data more effectively than was the case when the optimization method was based upon the NRTL equation.

• Proceedings of the Korean Nuclear Society Conference
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• 2005.10a
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• pp.207-208
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• 2005