• Membrane Journal
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• v.10 no.3
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• pp.121-129
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• 2000

The membrane requires both high in selectivity and flux. However, the permselective membrane has low flux. In this study, the porous alumina membrane was coated with silane coupling agent in order to enhance the flux with proper selectivity. The contact angle of water to the surface-modified alumina membrane was greater than 90$^{\circ}$, which indicated the high hydrophobicity. The modified membrane was tested in vapor permeation for the concentration of aqueous ethanol, isopropanol, and n-butanol. With the increase of ethanol, isopropanol, butanol concentration in the feed, permeation flux increased due to the greater affinity of ethanol, isopropanol, butanol with surface-modified alumina membrane than that of water. The experimental results showed that the permeation tate of surface-modified alumina membrane was 20~1000 times greater than that of a polymer membranes.

• Bulletin of the Korean Chemical Society
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• v.35 no.6
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• pp.1855-1858
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• 2014

• Microbiology and Biotechnology Letters
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• v.25 no.1
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• pp.44-50
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• 1997

$\beta $-Glucosidase (EC 3.2.1.21) was purified from Aspergillus niger SFN-416 by a sequential process of ammonium sulfate precipitation, Sepadex G-100 and DEAE-Sephacel column chromatography. Molecular weight of the enzyme was 46, 000 daltons. The K$_{m}$ and V$_{max}$ values for PNPG were 0.67 mM and 25 moles/ml $\cdot $min., respectively. The optimum pH and temperature of the enzyme activity were 3.5 and 58$\circ $C, respectively. The enzyme activity was decreased by addition of metal ions, and increased by addition of metanol, ethanol, isopropanol and 1-butanol at a concentration of 10% (v/v). Stability of the enzyme was increased by addition of isopropanol and 1-butanol at a concentration of 10% (v/v).

• Journal of the Korean Society of Food Science and Nutrition
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• v.27 no.6
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• pp.1166-1172
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• 1998

A method for the isolation and purification of DNA from a red algae, Porphyra was innovated. The innovation of the method consists mainly of three steps that include sodium acetate treatment, chloroform extraction, and 0.2 volume isopropanol precipitation step. The sodium acetate treatment was designed to remove polysaccharide contamination, and the isopropanol step to remove proteins and salts contaminents. Genomic DNA,s of several species(for example, P. tenera, P. yezoensis, P. seriata, and P. pseudolinearis) was successfully isolated by the innovated method. The amount of DNA purified from one g of sample material with the innovated method was 53 g in average. The resulting DNA was characterized to include high molecular weight and showed no nuclease activity. The DNA was pure enough to be digested directly by various restriction enzymes without any difficulties. Porphyra DNA was pure enough and adequate for amplification reaction through the polymerase chain reaction (small nuclear rDNA PCR amplification).

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.6 no.1
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• pp.19-23
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• 2000

The increasing use of plastics in food packaging materials has led to the issue of food-packaging mutual interactions from residues in the plastics. Plastic films are commonly printed by using solvent-based ink to decorate the packaged food for consumer attention. However, the residual solvents can not be completely removed and they can migrate into the contained food which lead to undesirable off-flavors. Partitioning (Kp) of printing ink solvents was studied in two types of plastic films with different chemical structure and polarity. At $25^{\circ}C$, Kp of toluene is higher than that of isopropanol in PP, but isopropanol showed higher Kp value than toluene in EVOH. This showed that polarity had a significant effect on the partitioning of printing ink solvents into the plastic films. Printing solvents had a higher affinity to the polymer with similar polarity than it did to the different one.

• Membrane and Water Treatment
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• v.7 no.2
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• pp.143-154
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• 2016

Acetic acid can be removed from wastewater by esterification in a membrane reactor. Pervaporation membrane reactor (PVMR) is an alternative process to conventional separation processes. It is an environmentally friendly process. The main advantages of the PVMR are simultaneous water removal and production of an ester economically. In this study, the synthetic wastewater has been used. Esterification reaction of acetic acid with isopropanol has been studied in the presence of tungstosilicic acid hydrate as a catalyst in a batch reactor and in a PVMR. The effects of important operating parameters such as reaction temperature, initial molar ratio of isopropanol to acetic acid and catalyst concentration has been examined. Removal of acetic acid (conversion of acetic acid) was obtained as 85% using a PVMR by removal of water from the reaction mixture.

• YAKHAK HOEJI
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• v.8 no.4
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• pp.89-93
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• 1964

Sustained-release dosage form of ferruginous hematinics which can be absorbed effectively without forming "iron block" that caused by high concentration of Iron in the gastrointestinal tract, was studied. Gelatinized micropellets containing medicament were prepared according to the method of N. Tanaka et al. and hardened in 10% formalin-isopropanol in various time. Gelatinized micropellets were digested with artificial gastric juice and prepared a graph of iron concentration determined by Hong's method. As a result, it is assumed that gelatinized sustained-release dosage form can be a good ferruginous hematinics and it is shown that the preparation of 72-hour-hardening in 10% formalin-isopropanol has a suitable sustained release.d release.

• Journal of the Korean Chemical Society
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• v.17 no.1
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• pp.10-14
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• 1973

The relative viscosities ηr of anilinium chloride solutions in a series of isopropanol-water mixtures have been determined at $20^{\circ}$, $30^{\circ}$and $40^{\circ}$, using Ubbelohde-type viscometers. The viscosity data have been interpreted in terms of viscosity A-and B-coefficients calculated from the Jones-Dole equation,${\eta}{\tau}=1+AC^{1/2}+BC$. The energy of activation for viscous flow have also been calculated according to the concept of rate processes. The results indicate that at $0.10{\sim}0.15$ mole fraction isopropanol the maximum structuredness of water gives a minimum values of viscosity A-and B-coefficients, and that anilinium chloride belongs to the borderline case in respect of the structure-making or structure-breaking effects on water.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.26 no.1
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• pp.20-29
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• 2016

Objectives: The purpose of this study is to simplify and standardize analytical method of polar solvents(methanol, isopropanol, n-butanol, acetone, methylene chloride and MIBK) in the working environmental by GC. Because NIOSH methods are various and complicated. Methods: The method is using the same stationary phase(5% phenyl 95% dimethylpolysiloxane), absorbent(silica gel) and desorption solvent(DMSO) for above 6 solvents. For the 6 solvents desorption efficiency, calibration curve, and limit of detection were studied Results: As the results, 6 solvents{2 groups ; first group(methanol/isopropanol/butanol) and second group(acetone/methylene chloride/MIBK)} could be separated and quantified within 10 minutes. Desorption efficiency from silica gell of 6 solvents using dimethylsulfoxide(DMSO) was methanol 86.2%, isopropanol 103.2%, n-butanol 101.8%, acetone 98.2%, methylene chloride 103.9% and MIBK 106.2% in the range of 0.2, 0.5, 2.0 times of TWA, consequently, satisfied NIOSH estimation level(beyond 75%). Correlation coefficient(r)in the range of 0.2~2.0 times of TWA, was above 0.999 for 6 solvent. LOD(mg/DMSO ml) using calibration curve in the range of 0.2~2 times of TWA was methanol 0.11, isopropyl alcohol 0.20, n-butanol 0.03, acetone 0.50, methylene chloride 0.05, MIBK 0.04 respectably. Conclusions: This method can be used at the sampling and analytical method for polar solvents by GC. Also, will be able to be applied with NIOSH methods.

• Applied Chemistry for Engineering
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• v.7 no.4
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• pp.794-801
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• 1996

$TiO_2$ fine powders were synthesized via hydrolysis reaction of titanium isopropoxide in isopropanol solvent and the reaction rates were studied by use of UV spectroscopic method. The reactions were controlled to proceed to pseudo-first-order reaction in the presence of excess water in isopropanol solvent. The rate constants which varied with temperature and concentration of water were calculated by Guggenheim method. Reactions using $D_2O$ were also carried out to determine the catalytic character of water. n value of water molecules in transition state and the thermodynamic parameters showed that the reaction proceeded by $S_N2$ mechanism. $TiO_2$ powders synthesized in this reaction were almost spheric forms and had average particle size of $0.3{\mu}m$ diameter.