• Journal of the Korean Applied Science and Technology
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• 제26권3호
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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 Pharmaceutical Investigation
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• 제16권1호
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• pp.8-11
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• 1986

There have been many difficulties in utilization of polyethylene (PE) container for volatile ingredients because of its high permeability. We selected glycol-modified polyethylene terephthalate (PETG) lately being used and evaluated the stability of 0.5% chlorobutanol solution for PETG. We used PE bottle, glass flask and rubber stoppered vial for comparison and assayed chlorobutanol contents of the samples stored at various temperatures for nine weeks by HPLC method. The results indicated that the stability of chlorobutanol in PETG container was almost similar to that in glass flask, and was superior to that in PE bottle and rubber stoppered vial.

• Bulletin of the Korean Chemical Society
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• 제26권7호
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• pp.1079-1082
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• 2005

The purpose of this study was to develop a method for increasing the solubility of paclitaxel in water to reduce its toxicity and make the drug more feasible for chemotherapy. A series of highly water soluble paclitaxel polyethylene glycol (PEG) esters were synthesized and evaluated for their anti-tumor activity and toxicity. The solubility of 7-polyethylene glycol paclitaxel carbonate 5 was 840 mg/mL and the acute toxicity ($LD_{50}$) was 286 mg/kg. Because of its reduced toxicity, compound 5 showed a dramatic reduction of tumor volume without any loss of animals in long-term treatment (daily consecutive injections for 15 days).

• Journal of the Korean Applied Science and Technology
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• 제29권1호
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• pp.54-62
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• 2012

In this experiment, the optimum concentration of polyols which were used for making transparent soaps was determined using design of experiment (DOE) method. Dipropylene glycol and 1,3 butylene glycol with short chains enhanced the transparency of soap, however, polyethylene glycol 400, glycerin and diglycerin made the soap opaque. The hardness of soap was increased as increasing the concentration of propylene glycol, diglycerin, dipropylene glycol and polyethylene glycol 400. The hardness, transparency, absorbance of water, and friction solubility could be optimized by controlling the concentration of dipropylene glycol, polyetylene glycol, sugar, and triethanolamine.

• Biotechnology and Bioprocess Engineering:BBE
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• 제6권4호
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• pp.269-273
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• 2001

This study presents a new formulation method for improving DNA transfection effi-ciency using a fusogenic peptide and polyethylene glycol-grafted polyethylenimine. Succinimidyls succinate polyethylene glycol (PEG-SSA) was conjugated with polyethylenimine(PEL). PEL is well known for a good endosomal escaping and DNA condensign agent. The positively charged syn-thetic fusogenic peptide, KALA was coated on the negatively charged PEG-g-PEI/DNA and PEI/DNA complexes. The KALA/PEI/ DNA complexes exhibited aggregation behavior at higher KALA coating amount with an effective diameter of around 1,000 nm. However, the LALA/PEG-g-PEI/DNA complexes were 100-300 nm in size with a surface zeta-potential (ζ)value of about +20mV. The conjugated PEG molecules suppressed any KALA-mediated inter-particle aggregation, and thereby improved the transfection efficiency, Consequently, the transfection efficiency of the KALA/PEG-g-PEI/DNA complexes was obtained by utilizing both the fusogenic activity of KALA and the steric repulsion effect of PEC.

• Journal of the Korea Furniture Society
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• 제27권1호
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• pp.43-48
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• 2016

PEG (Polyethylene glycol) impregnation in wood reduces the occurrence of checking during kiln drying. The volumetric shrinkages of wood PEG impregnated by pressure (PEG-P) or soaking (PEG-S) methods, and oven-dried by vent (VD) or air-tight (AD) methods were measured and compared with the controls. The average oven-dry weight of PEG impregnated specimens was larger than that of the controls by 3.6 g, but was not influenced by the drying methods. The average of the total volumetric shrinkage of PEG-P-VD specimens was the least (2.3%), while that of CON-S-AD specimens was the largest (28.9%). Within a drying method the total volumetric shrinkage of the control was the largest followed by PEG-S and PEG-P specimens, which implied that residual PEG in wood restrained its shrinkage during drying.

• Journal of the Korean Society of Industry Convergence
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• 제24권3호
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• pp.289-294
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• 2021

Tungsten (W) is used as a facing material for nuclear fusion reactors, and it is used in conjunction with structural materials such as copper alloy (CuCrZr), graphite, or stainless steel. On the other hand, since tungsten is a material with a high melting point, a method that can be manufactured at a lower temperature is important. Therefore, in this study, tungsten, which is a facing material, was attempted to be manufactured using a pressure sintering method. Material properties of sintered tungsten materials were analyzed for each solvent using two types of solvents, acetone and polyethylene glycol. The sintered tungsten material using acetone as a solvent exhibited a hardness value of about 255 Hv, and when polyethylene glycol was used, a hardness value of about 200 Hv was shown. The flexural strength of the sintered tungsten material was 870 MPa and 307 MPa, respectively, when acetone and polyethylene glycol were used as solvents. The sintered tungsten material using acetone as a solvent caused densification between particles, which served as a factor of increasing the strength.

• Korean Journal of Plant Tissue Culture
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• 제22권6호
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• pp.311-316
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• 1995

In an attempt to obtain intersubgeneric somatic hybrids of Pelargonium aridum and P.zonale, protoplast isolated from the two species were fused by using polyethylene glycol(PEG) and electorfusion methods. Protoplast were isolated from cotyledon and leaf tissues using MS medium containing 550 mM sucrose, 0.7% cellulase (Onozuka R-10) and 0.4% Macerozyme. The optimum number of protoplasts per mL of culture medium was 6 x 10$^4$. Protoplast fused by the electrofusion method were more active than by PEG method. Heterokaryotically fused protoplasts formed calli when cultured in MS medium containing 550 mM glucose, 1 to 2 mg/L NAA and 0.5 to 1 mg/L BA.

• Journal of Life Science
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• 제8권2호
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• pp.208-215
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• 1998

It was investigated the biosorption performances of copper by the immobilized biomass of nonliving marine brown alge h. fusiformis by each of the Ca-alginate method(Ca-ALG), Ba-alginate method(Ba-ALG), polyethylene glycol method(PEG), and carrageenan method (CARR). The copper removal performance increased but the copper uptake decreased as the biomass amount was increased. However, the copper uptake by the immobilized biomass increased with increasing initial copper concentration. The copper uptake by the immobilized biomass of the immobilization method decreased in the following sequence; Ca-ALG>Ba-ALG>PEG>CARR among the immoblization emthods. The copper uptake by the immobilized biomass followed the Langmuir isotherm better than the Freundlich isotherm.

• Clean Technology
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• 제21권2호
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• pp.124-129
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• 2015

The constant-volume method was used to determine the solubility of CO₂ in various physical absorbents such as DMPEG (dimethyl ether of polyethylene glycol), DEC (diethyl carbonate), DMC (dimethyl carbonate), and TAT (triacetin) in the total pressure range from 5 to 30 bar. The Peng-Robinson equation of state has been used to describe the equilibrium behavior of these mixtures. It was found that the solubility of absorbents was in the of DMPEG250 > TAT > DEC > DMC at the same temperature. Futhermore, the solubiity of blended absorbent of DMPEG250 and DEC is higher than that of DMPEG 250 alone. Therefore, blended absorbent of DMPEG250 and DEC is expected to be an effective and low cost absorbent for physical absorption in precombustion CO₂ capture.