• Bulletin of the Korean Chemical Society
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• v.28 no.8
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• pp.1265-1272
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• 2007

A solid acid catalyst, NiSO4/CeO2-ZrO2 was prepared simply by promoting ZrO2 with CeO2 and supporting nickel sulfate on CeO2-ZrO2. The support of NiSO4 on ZrO2 shifted the phase transition of ZrO2 from amorphous to tetragonal to higher temperatures because of the interaction between NiSO4 and ZrO2. The surface area of 10-NiSO4/1-CeO2-ZrO2 promoted with CeO2 and calcined at 600 oC was very high (83 m2/g) compared to that of unpromoted 10-NiSO4/ZrO2 (45 m2/g). This high surface area of 10-NiSO4/1-CeO2-ZrO2 was due to the promoting effect of CeO2 which makes zirconia a stable tetragonal phase as confirmed by XRD. The role of CeO2 was to form a thermally stable solid solution with zirconia and consequently to give high surface area and acidity of the sample, and high thermal stability of the surface sulfate species. 10-NiSO4/1- CeO2-ZrO2 containing 1 mol% CeO2 and 10 wt% NiSO4, and calcined at 600 oC exhibited maximum catalytic activities for both reactions, 2-propanol dehydration and cumene dealkylation.

• 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.

• The Korean Journal of Food And Nutrition
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• v.12 no.4
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• pp.375-379
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• 1999

Volatile components of Cornsilk(Zea mays L.) were isolated by purge and trap headspace method and were analyzed by GC and GC/MSD. A total of 44 components were identified in the cornsilk volatile coponents including 9 alcohols 7 aldehydes and ketones 14 terpenes and terpene alcohols 3 pyrazines 5 hydrocarbons and 6 miscellaneous components. The major components were 2-propanol(8.08%) pen-tanol(1.82%) hexanol(2.86%) hexanal(3.68%) heptanal(7.40%) nonanal(7.93%) decanal (2.04%) $\alpha$-copaene(2.20%) limonene(1.68%) $\alpha$-selinene(1.03%) $\beta$-selinene(1.03%)

• Membrane Journal
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• v.23 no.5
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• pp.367-374
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• 2013

In the present study, Pebax-2533 plate membranes were prepared by drying precursor solutions which were obtained by dissolving Pebax-2533 polymer in 1-Propanol/n-Butanol mixed solvents. And then the $CO_2$ and $N_2$ permeation behaviors were tested by using a time-lag system. The prepared Pebax-2533 plate membranes showed a considerable $CO_2/N_2$ separation performance : the $CO_2$ permeability was 130 to 288 barr, and the $CO_2/N_2$ permselectivity was 5-8. The $CO_2$ permeation data obtained by varying feed pressure, permeation temperature, and solvent composition announced that not only the $CO_2$ sorption but also the $CO_2$ diffusion is equally important in the overall $CO_2$ permeation.

• Bulletin of the Korean Chemical Society
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• v.27 no.6
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• pp.821-829
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• 2006

A series of catalysts, $NiO/La_2O_3-ZrO_2/WO_3$, for acid catalysis was prepared by the precipitation and impregnation methods. For the $NiO/La_2O_3-ZrO_2/WO_3$ samples, no diffraction lines of nickel oxide were observed, indicating good dispersion of nickel oxide on the catalyst surface. The catalyst was amorphous to X-ray diffraction up to 300 ${^{\circ}C}$ of calcination temperature, but the tetragonal phase of $ZrO_2$ and monoclinic phase of $WO_3$ by the calcination temperatures from 400 ${^{\circ}C}$ to 700 ${^{\circ}C}$ were observed. The role of $La_2O_3$ in the catalyst was to form a thermally stable solid solution with zirconia and consequently to give high surface area and acidity. The high acid strength and high acidity were responsible for the W=O bond nature of complex formed by the modification of $ZrO_2$ with $WO_3$. For 2-propanol dehydration the catalyst calcined at 400 ${^{\circ}C}$ exhibited the highest catalytic activity, while for cumene dealkylation the catalyst calcined at 600 ${^{\circ}C}$ showed the highest catalytic activity. 25-$NiO/5-La_2O_3-ZrO_2/15-WO_3$ exhibited maximum catalytic activities for two reactions due to the effects of $WO_3$ modifying and $La_2O_3$ doping.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.8 no.2
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• pp.307-314
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• 1998

PZT thin films were fabricated by the Sol-gel method. Starting materials used for the preparation of the stock solution were Pb-acetate trihydrate, Zr-normal propoxide and Ti-isopropoxide. 2-Methoxyethanol and iso-propanol were used for solution. For studying the diffusion of Pb ion into the substrates. We used bare Si substrate, $SiO_2/Si$ substrates which was produced by thermal oxidation and $TiO_2/SiO_2/Si$ which was mad by Sol-gel method. Densification and adhesion of thin films were observed by SEM. Phase formation of thin films and diffusion of Pb ion into the substrate were examined by XRD and ESCA, respectively. In the case of bare Si and $SiO_2/Si$ substrate, we obtained the perovskite phase at $700^{\circ}C$ and restricted a little the diffusion of Si ion into the film with $SiO_2$ buffer layer. In the case of $TiO_2/SiO_2/Si$, perovskite phase were obtained at $500^{\circ}C$ and the diffusion of Pb ion and Si ion were restriced.

• Journal of Korean Society for Atmospheric Environment
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• v.23 no.5
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• pp.539-546
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• 2007

Increasing emission of $CO_2$ significantly effects the global warming. Chemical absorption is one of separation methods of $CO_2$ from the industrial flue gases. In this study, the $CO_2$ removal efficiency as well as the $CO_2$ absorption amount of aqueous AMP (2-amino-2-methyl-1-propanol) solutions were measured using the continuous absorption and regeneration apparatus. We investigated the effect of aqueous AMP+AEPD(2-amino-2-ethyl-1, 3-propanediol) and AMP+TIPA (triisopropanolamine) solutions to enhance absorption characteristics of AMP. As a result of this study, the absorption amount and $CO_2$ removal efficiency were increased with adding TIPA into 30 wt.% AMP. The absorption amount and $CO_2$ removal efficiency of aqueous 30 wt.% AMP+5 wt.% TIPA solution were $1.70\;kg-CO_2/kg-absorbent$ and 91.1%, while those of aqueous 30 wt.% AMP solution were $1.58\;kg-CO_2/kg-absorbent$ and 89.3%. In addition, aqueous 30 wt.% AMP+5 wt.% TIPA solution used in the study revealed the high stripping efficiency, which was almost 98%, at the temperature of $110^{\circ}C$. Thus, the temperature of regenerator should be operated at $110^{\circ}C$.

• Korean Journal of Food Science and Technology
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• v.29 no.1
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• pp.183-187
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• 1997

The analytical conditions of 1,3-dichloro-2-propanol (DCP) and 3-chloro-1,2-propanediol (MCPD) by solid phase extraction were optimized to improve recovery. Selected-ion monitoring technique which was used for GC-MS analysis of both compounds gave substantially higher sensitivity. The detection limits of DCP and MCPD were 25 and 50 ppb, respectively. The effects of extraction column type, elution solvent and salt concentration on recovery were examined. A normal phase column was better than a reverse phase column in solid phase extraction of DCP and MCPD. It was explained in terms of polarity relationship of solvent-solute-solid phase. A maximum recovery was obtained at the salt concentration of 20% (w/v). Water-immiscible and chloropropanol-soluble solvents such as chloroform, diethyl ether, hexane and ethyl acetate were tested for elution solvent. Hexane and ethyl acetate were the most suitable solvents for the extraction of DCP and MCPD, respectively. High recovery better than 95% was obtained with the selected solvents.

• Korean Chemical Engineering Research
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• v.47 no.2
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• pp.185-189
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• 2009

Absorption rate of carbon dioxide into aqueous ammonia absorbent(10 wt%) was measured in the temperature range from 293 K to 337 K using a stirred-cell reactor. The reaction rate constant was correlated with the Arrehnius equation and the activation energy was 50.42 kJ/mol. $CO_2$ absorption rate into modified ammonia absorbent was also investigated. For the modified ammonia absorbent, 1 wt% sterically hindered amines of 2-amino-2-methyl-1-propanol(AMP), 2-amino-2-methyl-1,3-propandiol(AMPD) and 2-amino-2-ethyl-1,3-propandiol(AEPD) were used as additives. The $CO_2$ absorption rate increased by adding 1 wt% of the amine additive, in the case of AMP additive, the absorption rate enhanced by about 53%.

• 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