• Journal of Plant Biology
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• v.37 no.3
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• pp.271-276
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• 1994

The possibility that 1-aminocyclopropane-1-carboxylic acid (ACC)-uptake may be dependent on the H+-gradient established across the plsma membrane was tested in protoplasts isolated from 2.5 day old mungbean hypocotyls. The ACC-induced ethylene production was inhibited when the H+-gradient was collapsed by the treatment with carbonycyamide-p-trifluro-methoxy-phenylhydrazone (FCCP). Moreover, the treatment with o-vanadate, a specific inhibitor of plasma membrane H+-ATPase, caused the inhibition of ethylene production. The ACC-induced ethylene production was inhibited by the treatemnt with verapamil (Ca2+-channel blocker), or ethylene glycol-bis($\beta$-aminoethyl ether) N, N, N', N'-tetraacetic acid (EGTA) (Ca2+-chelator). In contrast, the ehtylene production was stimulated by the application of A23187 (Ca2+ ionophore). The inhibitory effect of EGTA in the ethylene producton was magnified in the presence of A23187. From these results, we suggest that the external Ca2+ influx to the cytosol resulted in the stimulatin of ACC oxidase activity after ACC-uptake resulting from a H+-gradient across the plasma membrane.

• Polymer(Korea)
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• v.35 no.2
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• pp.146-151
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• 2011

The physical properties of poly (ethylene 2,6-naphthalate) (PEN) copolymers were studied. PEN copolymers were synthesized successfully from the mixtures of ethylene glycol(EG), 1,3-propanediol (PD) and l,4-butanediol (BD) with 2,6-dimethyl naphthalene dicarboxylate. The results indicated that PEN copolymers showed an amorphous state when the content of BD(PD) in applied EG/BD(EG/PD) mixtures was less than 40% during the polycondensation. As a result, the lowering of thermal properties, orientation, and mechanical properties was found, however, the dimensional stability was improved. This is a promising result to apply the synthesized PEN copolymers as flexibles substrates.

• Fibers and Polymers
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• v.5 no.3
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• pp.230-233
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• 2004

The optimum conditions for durable press treatment of cotton fabrics using glyoxal as a nonformaldehyde crosslinking agent were investigated. Crosslinking reaction was conducted in the presence of different catalysts such as aluminum sulfate, magnesium chloride, or magnesium chloride-citric acid mixture at various mole ratios of catalyst to glyoxal. Aluminum sulfate was proven the most effective one among those used. Glycol addition into a glyoxal padding bath increased the wrinkle recovery angle(WRA) and whiteness of treated fabrics. The optimum mole ratio of glycol to glyoxal was 1:1. Diethylene glycol addition produced better overall performance to the glyoxal-crosslinked fabric compared to ethylene glycol addition.

• Journal of the Korean Applied Science and Technology
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• v.26 no.3
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• pp.306-316
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• 2009

In this study, block copolymer of polystyrene and polyethylene glycol methyl ether methacrylate(PEGMA) by ATRP(atom transfer radical polymerization) method was synthesized. 4 arm-molecule which contained halogen atom was synthesized for an initiator. With 4 arm-molecule monodispered polystyrene were synthesized by ATRP method. The molecular change of synthesized monodispersed polystyrene with respect to time was investigated and living polymer characteristic was confirmed. Block copolymer of polystyrene and polyethylene glycol methyl ether methacrylate(PEGMA) was synthesized by ATRP with macroinitiator which was synthesized from the monodispersed polystyrene(Mn=12000). The molecular weight of obtained PS-b-PEGMA was 22,000.

• Journal of the Korean Applied Science and Technology
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• v.30 no.1
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• pp.116-126
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• 2013

Glycol ethers are a group of solvents based on alkyl ethers of ethylene glycol commonly used in paints. These solvents typically have a higher boiling point, together with the favorable solvent properties of lower-molecular weight ethers and alcohols. The word "Glycol ethers" was registered as a United States trademark by Union Carbide Corp. Typically, glycol ethers are found in pharmaceuticals, sunscreens, cosmetics, inks, dyes and water based paints. On the other hand, glycol ethers are used in degreasers, cleaners, aerosol paints and adhesives. Most glycol ethers are relatively water soluble, biodegradable and only a few are considered toxic. Therefore, they are unlikely to pose an adverse risk to the environment. Recent study suggests that occupational exposure to glycol ethers is related to low motile sperm count in men, but the finding has been disputed by others. In this study, skin permeation of 3 types glycol ethers were studied in vitro using matrix such as solvent and detergent. The absorption of glycol ethers[methyl glycol ethers(MC), ethyl glycol ethers(EC) and butyl glycol ethers(BC)] has been measured in vitro through rat skin. Epidermal membranes were set up in Franz diffusion cells and their permeability to PBS measured to establish the integrity of the skin before the glycol ethers were applied to the epidermal surface. Absorption rates for each glycol ethers were determined and permeability assessment made to quantify any irreversible alterations in barrier function due to contact with the esters. Types of glycol ethers in vitro experimental results on MC> EC> BC quickly appeared in the following order: skin permeation was beneficial to the skin permeation small molecular weight, the difference in chemical structure, such as hydrophilic, because with the partition coefficient and solubility mechanisms and passive diffusion to increase the speed at which transmission is considered.

• Journal of Biomedical Engineering Research
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• v.28 no.2
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• pp.244-249
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• 2007

Fluidic conditions for the separation of phases were surveyed in a microfluidic aqueous two-phase extraction system. The infusion ratio between polyethylene glycol (PEG) and dextran solution defines the concentrations of each polymer in micro-channel, which determine the phase-separation. The appropriate ratio between PEG (M.W. 8000, 10%, w/v) and dextran T500 (M.W. 500000, 5%, w/v) in order to perform the separation of phases of both polymers was observed as changing the mixed ratio of both polymers. Based on the fluidic conditions, stable two-phase solutions were obtained within 4% to 8% and 3% to 1% of PEG and dextran, respectively. In addition, the characteristics of the two-phase were discussed. The separation technique studied in the paper can be applied for the implementation of a lab-on-a chip which can detect various biological entities such cells, bacterium, and virus in an integrated manner using built in a biosensor inside the chip.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.17 no.9
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• pp.1001-1005
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• 2004

Rye-sensitized solar cell (DSSC) is a new class of solar cell, which consists of nanoporous TiO$_2$ electrode, dye-sensitizer, electrolyte, and counter electrode. Such cell is operated in sunlight via the principle of photosynthetic electrochemistry. In order to obtain the good dispersion of nano size TiO$_2$ particles In slurry, the pH of solvent, the sort and quantify of solvent additive and the quantity of surfactant were adjusted. 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 TiO$_2$ film using the dilute HNO$_3$ solvent of pH 2 with the addition of ethylene glycol and neutral surfactant. DSSC was assembled with TiO$_2$ electrode and Pt electrode, and its photoelectric property was measured using the monochromatic wavelength in the rangee of 350∼700 nm.

• Journal of the Korean Applied Science and Technology
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• v.20 no.1
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• pp.44-50
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• 2003

We studied on the preparation and evaluation of O/W type microemulsion containing "wax, liquid paraffine and quaternary ammonium salt". And also it was obtained to stability of microemulsions by mono ethylene glycol(MEG) addition. The microemulsions were generally prepared at 96${\sim}$97$^{\circ}C$ by the phase inversion method. We used polyoxyethylene(20) sorbitan monooleate(POE(20)SMO) and distearyl dimethyl ammonium chloride(D.D.A.C.) as the emulsifiers at microemulsion preparation. From the results, we could get best condition for microemulsion preparation, in case of oil phase, montanic ester wax ; 1.1wt%, paraffine wax ; 1.1wt%, liquid paraffine ; 3.1wt%, propylene glycol ; 0.6wt% and ethylene glycol monobutyl ether ; 0.6wt%, when the ratio(wt%) of D.D.A.C. and POE(20)SMO were 2 : 3. And also we could obtained that the distributed particle size of the final microemulsions were about 8${\pm}$1.5nm and the mean particle size was 7${\pm}$0.5nm. We got following results from final microemulsions that the percent of transmittance; 96${\sim}$98% at 700nm. And the microemulsion blended with MEG of 5${\sim}$15wt% showed smaller particle size and more stable distribution than non-containing MEG.

• Proceedings of the Korean Fiber Society Conference
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• 2003.04a
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• pp.33-35
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• 2003

Over the last 30 years, water-swellable and water-insoluble hydrogels have been extensively investigated and developed, leading to a large family of materials which have found use in a wide range of biomedical applications such as carriers of soft tissues, wound healing, ophthalmological applications, membranes for artificial kidney, and materials for blood compatible and other medical devices[1-3]. (omitted)

• Journal of the Korean Chemical Society
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• v.24 no.6
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• pp.463-468
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• 1980

Tris(hydroxyethyl) phosphate, ethylphosphoramidic dichloride, N,N-diethylphosphoramidic dichloride, bis(hydroxyethyl) N-ethylphosphoramidate and bis(hydroxyethyl) N,N-diethylphosphoramidate were synthesized and characterized. Phosphate and phosphoramidates were polymerized with the elimination of ethylene glycol when heated under reduced pressure and they gave no molecular ion peaks in their mass spectra. And also ethylphosphoramidic dichloride gave polymeric products at 180$^{\circ}C$ with the evolution of HCl. IR spectra showed characteristic P=O streching bands in the range of 1,300 to$ 1,200 cm^{-1}.$