• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2003.07a
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• pp.308-311
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• 2003

The mesoporous TiO2 film for the dye-sensitized solar cell was prepared by the spin coating using nano particle $TiO_2$ slurry. In order to obtain the good dispersion of nano size $TiO_2$ particles in slurry, the pH of solvent, the sort and quantity of solvent additive and the quantity of surfactant were adjusted. The experimental range of pH was $2\;{\sim}\;4$. The basic solvent for slurry was dilute $HNO_3$ and the solvent additives were ethylene glycol, propylene glycol and butylene glycol. The degree of particle dispersion was indirectly estimated by the viscosity of slurry and the microstructure after sintering. As results, the lower the pH of solvent was the lower the viscosity of the slurry became. The addition of ethylene glycol and propylene glycol to dilute $HNO_3$ brought about the lowering of viscosity and the enhancement of stability in slurry. The addition of surfactant lowered the viscosity of slurry. It was possible to obtain the homogeneous and uniformly dispersed mesoporous TiO2 film using the dilute HNO3 solvent of pH 2 with the addition of ethylene glycol, propylene glycol and neutral surfactant.

• Analytical Science and Technology
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• v.19 no.4
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• pp.323-332
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• 2006

This paper discusses several low-temperature heat-tranfer fluids, including water-based inorganic salt, organic salt, alcohol/glycol mixtures, silicones, and halogenated hydrocarbons in order to choose the best heat-transfer fluid for the newly designed direct contact refrigeration system. So, it contains a survey on commercial products such as propylene glycol and potassium formate as newly used in super market and food processing refrigeration. The stability of commercial fluids at the working temperature of $-20^{\circ}C$ was monitored as a function of time up to two months. And organic and inorganic compositions of candidate fluids were obtained by analytical instruments such as ES, XRF, AAS, ICP-AES, GC, and GC-MS. Analysis results indicate that commercial propylene glycol is very efficient and safe heat transfer fluids for the direct cooling system with liquid phase.

• Journal of Pharmaceutical Investigation
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• v.34 no.1
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• pp.29-34
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• 2004

The solubility and stability of quercetin in various vehicles were determined. The solubility of quercetin at $28^{\circ}C$ increased in the rank order of isopropyl myristate < oleyl alcohol < propylene glycol monolaurate < oleoyl macrogol­6 glycerides < linoleoyl macrogol-6 glycerides < propylene glycol laurate (PGL) < propylene glycol monocaprylate (PGMC) < polyethylene glycol-8 glyceryl linoleate < caprylocaproyl macrogol-6 glycerides < diethylene glycol mono ethyl ether (DGME). The addition of DGME to non-aqueous vehicles such as PGL ad PGMC markedly increased the solubility of quercetin. From the stability studies, it was found that quercetin was unstable due to rapid oxidation by dissoved oxygen. The addition of a combination of ascorbic acid and edetic acid (EDTA) at 0.1 % markedly decreased the degradation rates of quercetin in 40% polyethylene glycol 400 in saline. Quercetin was relatively unstable in non-aqueous vehicles such as PGL and PGMC alone, and PGL-PGMC co-solvent The degradation of quercetin in such non-aqueous vehicles was fast, depending on temperature. The addition of butylated, hydroxytoluene, butylated hydroxyanisole, citric acid and/or EDTA at 0.1 % was effective in retarding the degradation of quercetin.

• Toxicological Research
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• v.34 no.4
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• pp.355-361
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• 2018

Methylisothiazolinone (MIT) has been used in combination with methylchloroisothiazolinone (CMIT) for cosmetic products such as shampoo, body lotion, and skin care products. The mixture of CMIT/MIT has been found to cause allergic contact dermatitis and is thus no longer permitted for use as a preservative in leave-on cosmetics. However, MIT itself was approved as a stand-alone preservative at a maximum concentration of 100 ppm as the toxicity was derived from CMIT rather than MIT. However, in many countries, allergic skin irritation caused by MIT remains a social concern. In this study, skin irritation was assessed for the presence of MIT, propylene glycol, and their mixture using a 3D human skin model $EpiDerm^{TM}$. Although non-diluted MIT causes serious skin toxicity, skin irritation was not observed at a concentration of 100 ppm, the maximum permissible level for cosmetics and personal care products according to European regulations. Propylene glycol, the most widely used vehicle for MIT, did not cause skin irritation in the 3D skin model. The results are expected to provide information for regulatory policies and guidelines on the use of biocides in consumer products.

• Korean Chemical Engineering Research
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• v.47 no.3
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• pp.380-385
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• 2009

The absorption rate of carbon dioxide with 2-amino-2-methyl-1-propanol(AMP) was measured in such non-aqueous solvents as methanol, ethanol, n-propanol, n-butanol, ethylene glycol, propylene glycol, and propylene carbonate, and in water at 298 K and 101.3 kPa using a semi-batch stirred tank with a plane gas-liquid interface. The overall reaction rate constant, obtained under the condition of fast reaction regime, from the measured rate of absorption was used to get the elementary reaction rate constants in complicated reactions represented by reaction mechanism of carbamate formation and the order of overall reaction of $CO_2$ with amine. The correlation between the elementary reaction rate constant and the solubility parameter of the solvent was also presented.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.19 no.1
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• pp.108-126
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• 1993

The functions of polyoxyethylene tocopheryl ethers [POE(n)TEs] in emulsion, solubilization and gel were studied. For emulsification of liquid paraffin, POE(10)TE showed better emulsifying effect in O/W emulsions than others tested. The effects of oil and polyol content on the formulation of W/O and O/W emulsions were also studied. In O/W emulsion, the viscosity was increased by increasing the liquid paraffin content, at about 70%, and slightly increased by increasing the propylene glycol content, However, in W/O emulsion, the viscosity was decreased by increasing the oil content, and also decreased by increasing the propylene glycol content, For solubilization of perfume oil, POE(18)TE showed better solubilizing effect than the others tested. The gelling effect of POE(n)TEs increased with ethylene oxide chain length up to 50 moles. The gelling property was evaluated for hardness and viscosity.

• Journal of Pharmaceutical Investigation
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• v.26 no.4
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• pp.263-271
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• 1996

Sulconazole nitrate(SCN), an imidazole derivative which has been effective in the treatment of dermatophytosis, tinea versicolor and candidiasis, was formulated as a gel containing drug, poloxamer 407, ethanol and propylene glycol. The resulting SCN gels were evaluated with respect to their viscosity, drug release rate, skin permeation rate. The apparent viscosity of SCN gel increased in proportion to poloxamer 407, drug and propylene glycol concentration. In case ethanol was added, the apparent viscosity decreased. The drug release rate of SCN gel increased in proportion to temperature and ethanol concentration. But the drug release rate decreased as the concentration of poloxamer 407 increased. The increase of drug concentration induced nonlinear increase of drug release rate. When propylene glycol was added at the level of 10%, the drug release rate increased but from 15% it decreased. The skin permeation rate decreased in high concentration of poloxamer 407. The skin permeation rate of SCN gel containing 15% ethanol increased about twice than that of gel without ethanol. The increase of drug concentration induced nonlinear increase of skin permeation rate. When propylene glycol was added at the level of 10%, the skin permeation rate increased but from 15% it decreased.

• Journal of the Korean Society of Tobacco Science
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• v.10 no.2
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• pp.123-130
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• 1988

The volitile compounds Produced from the Maillard reaction of D-glucose and DL-alanine or DL-$\alpha$-aminobutyric acid using water or propylene glycol as a reaction amdeum were analysed by gas chromatofiraphy and mass spectrometry. From two kinds of reaction products in water 18 compounds were identified. The major compounds in a reaction product of glucose with alanine were 5-hydroxy methyl-2-furfural, 2-acetyl pyrrole and 2-formyl-5-methyl pyrrole, and those in a reaction product of glucose with $\alpha$-aminobutyric acid were 2-ethyl crotonaldehyde and 2-methyl-3, 5-dihydroxy-4H-pyran-4-one including the above 3 compounds. From two kinds of reaction products in propylene glycol solution, 35 compounds were identified. The major compounds in a reaction product of glucose with alanine were alkyl pyraainef, 2-methyl furfuryl alcohol and 2-acetyl pyrrole, and those in a reaction product of glucose with $\alpha$-aminobutyric acid were propionaldehyde PGA, 2-ehtyl crotonaldehyde, 2-acetyl pyrrole and 2-acetyl-5-ethyl furan.

• Journal of Pharmaceutical Investigation
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• v.33 no.1
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• pp.45-49
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• 2003

The solubility and stability of ondansetron hydrochloride (OS) in various vehicles were determined. The effect of cyclodextrins (CD) on the solubility of OS in water was determined by equilibrium solubility method. The solubility of OS at $32^{\circ}C$ increased in the rank order of isopropyl myristate (IPM) < propylene glycol laurate (PGL) ${\ll}$ propylene glycol monolaurate < propylene glycol monocaprylate (PGMC) < poly(ethylene glycol) 400 < diethylene glycol mono ethyl ether (DGME) < ethanol < poly(ethylene glycol) 300 < water (36.1 mg/ml) ${\ll}$ propylene glycol (PG) (283 mg/ml). The addition of PG or DGME to non-aqueous vehicles such as IPM, PGL and PGMC markedly increased the solubility of OS. The addition of CDs in water increased the solubility. Apparent stability constant for the CD complexation with OS was calculated to be $25.5\;M^{-1}$ for $2-hydroxypropyl-{\beta}-CD\;(2HP{\beta}CD)$. Twenty mM ${\beta}-CD$, 69.4 mM sulfobutyl ether ${\beta}-CD$ and 115.4 mM $2HP{\beta}CD$ increased the aqueous solubilty of OS 1.27, 2.18 and 1.85 times, respectively. OS was stable in buffered aqueous solution (pH 5.0). However, OS was relatively unstable in non-aqueous vehicles in the order of PG

• Clinical and Experimental Reproductive Medicine
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• v.17 no.2
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• pp.167-172
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• 1990

This study was carried out to clarify the effects of various kinds of cryoprotectants which were frequently used in freezing embryos of domestic animals on the survival of frozen-thawed mouse embryos. Mouse embryos were collected by hyperstimulation induction of ICR mouse. The samples were slowly cooled ($l^{\circ}C/min$) to temperatures between $-7^{\circ}C$ and $-30^{circ}C$ before direct transfer to liquid nitrogen ($-196^{\circ}C$) and thawed rapidly ($-500^{\circ}C$/min). As cryoprotectants, Glycerol, DMSO, Ethylene glycol and Propylene glycol were used and applied each 2 cell, 8 cell, morula in embryo stage. After normal mouse embryos developed to blastocyst by in vitro culture, we observed recovery rate and developing rate of embryos at thawing. The results obtained in these experiments were as follows : 1. The in vitro development rate from the frozen-thawed 2 cell embryos to the blastocyst were 67.7% in ethylene glycol, 65.7% in Propylene glycol, 55.2% in glycerol and 50.0% in DMSO respectively. 2. The in vitro development rate from the frozen-thawed 8 cell embryos to the blastocyst were 83.6% in DMSO, 75.7% in glycerol, 52.2% in propylene glycol respectively. 3. The in vitro development rate from the frozen-thawed morula to the blastocyst were 84.2% in glycerol, 80.0% in DMSO, 66.6% in propylene glycol and 55.2% in ethylene glycol respectively.