• Korean Chemical Engineering Research
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• v.51 no.5
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• pp.580-586
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• 2013

In this paper, polymer composite membranes and ceramic composite membranes were prepared in order to compare differences in pervaporation performances relative to the support layers. PVDF was used for the polymer support layers, and $a-Al_2O_3$ was used for the ceramic support layers. For active layer was coated for PDMS, which is a rubbery polymer. The characterization of membranes were analysed by SEM, contact angle, and XPS. We studied performances relative to the composite membrane support layers in the ABE mixture solutions. The results of the pervaporation, the flux of the ceramic composite membrane was shown to be $250.87g/m^2h$, which was higher than that of polymer composite membranes, at $195.64g/m^2h$. However, it was determined that the separation factor of the polymer composite membranes was 31.98 which were higher than that of the ceramic composite membranes, at 20.66.

• Korean Journal of Food Science and Technology
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• v.26 no.3
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• pp.204-212
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• 1994

To estimate the possibility of wine-making with Korean dried persimmon, its homogenized and filtered solution was fermented at $15^{\circ}C$ and $25^{\circ}C$ for 12 weeks with Saccharomyces cerevisiae (Japan Alcoholic Beverage Association N0.7). Sugars of dried persimmon were mainly composed of 27.02% of glucose, 19.81% of fructose and 5.12% of mannose. In the fermentation at $25^{\circ}C$, glucose was almost completely consumed in 8 days, but fructose and mannose were consumed up to 64% and 74%, respectively, in the same period and were not utilized any more afterwards. In the fermentation at $15^{\circ}C$, 75% of glucose, 20% of fructose and 49% of mannose were consumed in 8 days and these sugars were continuously utilized for 12 weeks. Organic acids in the homogenized and filtered solution were levulinic acid (148.6 mg%), 4-methylvaleric acid (73.5 mg%), oxalic acid (28.7 mg%), acetic acid (8.5 mg%), N-butyric acid (8.4 mg%) and succinic acid (6.7 mg%). Irrespective of fermentation temperature, levulinic acid rapidly reduced according to progression of fermentation. Oxalic acid, N-butyric acid and succinic acid decreased at 2nd day of fermentation, and then increased at 4th and 6th days and subsequently decreased again under the levels of the solution. Acetic acid and 4-methylvaleric acid increased with the proceeding of fermentation and at 12th week of fermentation these contents were more than those of the solution. The contents of total free amino acid significantly reduced at 2th day of fermentation and then increased to the level of the solution at 12th week irrespective of fermentation temperature. Ethanol content rapidly increased to the levels of 5.3(v/v) at $15^{\circ}C$ and 9.4%(v/v) at $25^{\circ}C$ to 8th day after fermentation, but at 12th week its content was 14.5%(v/v) at $15^{\circ}C$ and 9.4%(v/v) at $25^{\circ}C$. The higher alcohots identified were 2-methyl-l-propanol, 3-methyl-ibutanol, 2-methyl-l-butanol and 2-methyl-2-propanol and the range of those contents was from 0.001% (v/v) to 0.06%(v/v). The color of the wine fermented at $15^{\circ}C$ was slightly superior but flavor and taste were slightly superior in the wine fermented at $25^{\circ}C$.

• Bulletin of the Korean Chemical Society
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• v.32 no.1
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• pp.71-76
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• 2011

An efficient nucleophilic [$^{18}F$]fluorination has been studied to reduce byproducts and preparation time. Instead of conventional aqueous solution of $K_2CO_3-K_{222}$, several organic solution containing inert organic salts were used to release [$^{18}F$]fluoride ion and anion bases captured in the polymer cartridge, concluding that methanol solution is the best choice. Comparing to azeotropic drying process, one min was sufficient to remove methanol completely, resulting in about 10% radioactivity saving by reducing drying time. The polymer cartridge, Chromafix$^{(R)}$ (PS-$HCO_3$) was pretreated with several anion bases to displace pre-loaded bicarbonate base. Phosphate bases showed better results than carbonate bases in terms of lower basicity. tert-Butanol solvent used as a reaction media played another critical role in nucleophilic [18F]fluorination by suppressing eliminated side product. Consequent [$^{18}F$]fluorination under the present condition afforded fast preparation of reaction solution and high radiochemical yields (98% radio-TLC, 84% RCY) with 94% of precursor remained.

• Membrane Journal
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• v.9 no.4
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• pp.221-229
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• 1999

The nominal pore size 0.2 ${\mu}m polytetrafluroethylene(PTFE, Satorius Co,) membrane was used for the filtration of 0.1 wt% kaolin, bentonite, yeast, and starch solution, respectively. After filtration, the membrane was cleaned and the pore size was measured by liquid displacement method(LDMl using water/iso-butanol system. The pore size for new PTFE membrane evaluated by LDM was comparable with those of which were measured by mercury porosimetry and scanning electron microscope. The membrane pores were severely fouled, and constricted to below 0.3 ${\mu}m in the cases of bentonite and starch solution which contained smaller particles than pores. However, in the case of kaolin - solution, only some parts of membrane pores above 0.35 ${\mu}m were slightly fouled. Hence, the phenomena of membrane fouling could be identified quantitatively by the evaluation of pore size using LDM.

• Journal of Sericultural and Entomological Science
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• v.28 no.1
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• pp.15-23
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• 1986

This study has been carried out to acquire some basic informations on the digestive fluid of Silkworm, Bombyx mori for developing artficial diets. Silkworms reared on mulberry leaves and artificial diet, were used in this experiments. The results obtained are as follows ; 1. The Red Fluorescent protein was precipitated in 50% acetone solution and did not dissolved in n-butanol solution, but dissolved in methanol solution. 2. Electrophoretic analysis results of mulberry leaves rearing B. mori and artificial diet rearing B. mori, which has been treated with 50% acetone solution were as follows. i) There was distinct difference at the position of high mobility ii) Red Fluorescence was observed only at the position of first band of mulberry leaves rearing B. mori. iii) No different was shown in the electrophoretic patterns of mulberry leaves rearing B. mori on 5th instar 1st-3rd day, but some difference on 5th instar 4th, 5th day. 3. The RFP is the basic protein which has PI 8-9 according to the isoelectric electrophhoresis. 4. The SDS-polyacrylamide gel electrophoresis analysis showed that the molecular weight of RFP was 27,000. 5. The Sephadex G-75 chromatographic analysis showed that there was three peaks between number 16 and 28 in the mulberry leaves rearing B. mori chromatogram, but two peaks between number 18 and 31 in the artifical diet rearing B. mori chromatogram.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2008.06a
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• pp.64-65
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• 2008

3D microbattery에 사용할 수 있는 $LiMn_2O_4$ 3차원 박막전극을 제조하여 그 전기화학적 특성을 관찰하였다. 3차원 구조의 형성을 위하여 먼저 polystyrene(PS) microsphere를 platinum이 증착된 Si/$SiO_2$ 기판위에 dip-coating 방식으로 코팅시켜 template로 사용하였다. 그 위에 sol-gel법을 이용, 박막을 형성시킨 후 template 를 제거하는 방식으로 $LiMn_2O_4$ 3차원 박막전극을 형성하였는데 이때 solution은 Lithium acetylacetonate[$LiCH_3CO-CHCOCH_3$], Manganese(III) acetylacetonate [Mn$(CH_3COCHCOCH_3)_3$]를 source 물질로 1-butanol과 acetic acid를 solvent로 활용하여 제조하였다.

• Journal of Soil and Groundwater Environment
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• v.15 no.1
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• pp.66-72
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• 2010

The partitioning tracer method is to estimate the residual saturation of nonaqueous phase liquid (NAPL) in soils by analyzing tracer's retardation induced by the reversible partitioning of tracer with NAPL. This study is to estimate the residual diesel saturation in soils using the partitioning tracer method. Two-dimensional soil box was used to represent the 2-dimensional flows of groundwater and tracer solution in the saturated aquifer, and the soil box was filled with soil and then saturated with water. The residual diesel saturation was induced in saturated soil, and the partitioning tracer method was applied. The results from batch-partitioning experiment indicated that the diesel-water partitioning was linear with respect to tracer's concentration, and the partition coefficient of tracer between diesel and water was measured by their linearities. The groundwater flow in the saturated aquifer was simulated in the 2-dimensional soil box, and the residual diesel contamination was visually identified. The results from the partitioning tracer method with or without diesel in soils confirmed that 4-methyl-2-pentanol, 2-ethyl-1-butanol and 1-hexanol, can be used as a detecting method for diesel contamination. By the accuracies of estimations for diesel contamination using the partitioning tracer method, 2-ethyl-1- butanol showed the highest accuracy with 83%.

• International Journal of Industrial Entomology and Biomaterials
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• v.16 no.2
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• pp.57-59
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• 2008

While searching for pancreatic lipase inhibitors, the active compound was found in a methanol extract of Apis mellifera venome. The active compound was isolated by Diaion HP-20 column chromatography, thin layer chromatography and HPLC. The active compound is stable to the extreme pH and heat. There is no loss of activity both in acidic and alkaline solution in the pH range of 2 to 11 by heating for 15 minutes at $90^{\circ}C$. The rf value of the compound was 0.51 at TLC with butanol : methanol: water (4:1:2) solvent system. The molecular weight of the compound was determined to be 293 by EI-MS.

• Membrane Journal
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• v.18 no.3
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• pp.214-218
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• 2008

Protain affinity membranes based on PES-BSA was preapared by the electrospinning method. The process problem caused by the electrospining was solved by using HFB having high solubility and boiling point. It was expecting that the mass production of protein affinity membrane would be possible with broad range of optimized temperature and humidity. BSA in the PES nanofiber was confirmed by the color change from colorless to violet during the biuret test. The buffer solution with DMSO showed that the amount of elution was 5 times higher than the one when the buffer solution without DMSO was used. This is due to the restriction effect of DMSO on the dissociation of L-tryptophan from BSA during the washing step.

• Journal of the Korean Applied Science and Technology
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• v.36 no.2
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• pp.407-416
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• 2019

The criticical micelle concentration (CMC) was measured by using the UV-Vis method for the micellization of the ammonium type cationic surfactants (DTAB, TTAB, and CTAB) in the aqueous aniline solution. The enthalpy change (${\Delta}H^0$) and entropy change (${\Delta}S^0$) were calculated from the dependence of Gibbs free energy change (${\Delta}G^0$) on the temperature for micellization of the cationic surfactants between 290K and 314K. The effects of n-butanol and sodium chloride on the micellization of cationic surfactants were measured and compared with the other thermodynamic functions. All the free energy changes (${\Delta}G^0$) of the micellization were negative, all the enthalpy change (${\Delta}H^0$) were negative, and all the entropy change (${\Delta}S^0$) were positive values, respectively. The micelle formation of cationic surfactant in aniline solution is a spontaneous exothermic reaction, and the iso-structural temperature calculated from the thermodynamic values show that enthalpy and entropy contribution to the micellization are almost the same for the micellization of cationic surfactants