• Macromolecular Research
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• 제11권4호
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• pp.291-295
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• 2003

Dextran as a candidate material for colon-specific drug delivery has been studied. Crosslinked dextran hydrogels were prepared by mixing dextran, $MgCl_2$, glutaraldehyde (GA) and polyethyleneglycol (PEG 400) in water. The dextran hydrogels were characterized by measuring equilibrium swelling ratios and mechanical strengths. Response surface methodology (Central Composite Design) was used to evaluate the swelling behaviors and mechanical strengths as functions of concentrations of $MgCl_2$, GA, and PEG 400, which was found to be useful for the evaluation. It showed that the swelling behavior and mechanical strengths were influenced significantly by PEG 400 and $MgCl_2$ concentrations.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1994년도 하계학술대회 논문집 C
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• pp.1330-1332
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• 1994

In order to investigate the properties of electrical conduction and space charge in crosslinked polyethylene film, we were observed the specimen with 200[${\mu}m$] thickness. The electrical conduction properties of specimen were measured temperature range from 30 to $110[^{\circ}C] $as well as $10^{-2}$ - 1 [MV/cm] of electric field. The investigations on influence of space charge were carried out at room temperature and $60 [^{\circ}C]$.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2000년도 하계학술대회 논문집 C
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• pp.1566-1568
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• 2000

This study refers to the crosslinked characteristics of XLPE cables by aging. The cable failure brings about an enormous loss of power supply and the immense expense for cable replacement. These characterization techniques can be used for identifying a cause of failure and for improving a quality of equipments Also, these play an important role in the detection of premature failure. In order to maintain a cable reliability, quality control is needed strictly. It can be possible to estimate a residual lifetime of power cable using characterization techniques.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1999년도 추계학술대회 논문집
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• pp.347-349
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• 1999

We have fabricated insulating thin films using p-hexadecoxyphenol(p-Hp) that was formed phenol-formaldehyde resin of crosslinked structure from reaction with formaldehyde by LB technique. For fabricated MIM device, the possibility for insulating layers of electronic were investigated by electrical properties of their LB films according to crosslinking of LB films current-voltage (I-V) properties and frequency-capacitance (C-F) characteristics. We have provided evidence for the high insulating performance of phenol-formaldehyde thin films by the LB method. Conductivity of their LB films was as follows: pure water > 1 % aq. Formaldehyde > heat treatment, in the current-voltage (I-V) characteristics. It is demonstrated that insulation properties of crosslinked p-HP LB films were improved. In capacitance-frequency properties, the heat-treated p-HP LB films for crosslinking showed a low relative dielectric constant.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2000년도 춘계학술대회 논문집 유기절연재료 방전 플라즈마
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• pp.33-36
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• 2000

Electrical properties of Crosslinked polyethylene/silane crosslinked polyethylene (XLPE/SXLPE) blends were studied. Silane coupling agents of various contents were added to blends and their water tree and electrical breakdown characteristics were investigated. The water tree length of XLPE/SXLPE were increased by the addition of silane coupling agents except the case of SXLPE 10 % containing coupling agents of 0.5, 1.0 phr. AC breadown strength slightly increased by the addition of coupling agents to XLPE/SXLPE blends in cases of SXLPE 20 % containing coupling agents of 2.0 phr and SXLPE 50 %. The tendency of effects on water tree and breakdown characteristics was inverse.

• Journal of Pharmaceutical Investigation
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• 제21권2호
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• pp.91-95
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• 1991

Polyethylene glycol, polypropylene glycol and block copolymer of ethylene glycol and propylene glycol were crosslinked by triisocyanate to form water swellable, rubbery polymer. The equilibrium swelling of the hydrogels ranged from 3% to 60% according to the hydrophobic-hydrophilic properties of the prepolymers. Model drugs, sodium salicylate and prednisolone were incorporated in the polymer matrices by swelling loading. Physical properties of the drugs affected the drug release mechanisms due to the change in the swelling behaviors of the polymeric devices. Zero order release was observed in the case of relatively hydrophobic polymer matrices.

• 환경위생공학
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• 제23권2호
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• pp.47-53
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• 2008

The ion exchange resins have been synthesized from chloromethyl styrene (dangerous matter) 1, 4-divinylbenzene(DVB) with 1%, 5%, and 15%-crosslinked and macrocyclic ligand of cryptand type by copolymerization method and the adsorption of uranium(VI), cobalt(II) and europium(III) ions have been investigated in various experimental conditions. The correlation between the adsorption characteristics of rare earths and transition metal on the resins and stability constants of complexes with macrocyclic ligand have been examined. The uranium ion was not adsorbed on the resins below pH 2.0, but the power of adsorption of uranium ion increased rapidly above pH 3.0. The adsorption power was in the order of 1%, 5% and 15%-crosslinked resin, but adsorptive characteristics of resins decreased in proportion to the order of dielectric constants of solvents.

• 한국응용과학기술학회지
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• 제15권1호
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• pp.35-45
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• 1998

Chitin/chitosan be known as biodegradable natural polymer. However, commercial use of chitin has been limited due to highly resistance to chemicals and the absense of proper solvents. Therefore, we was studied that chitin was prepared by the application of Hackman's method from Protunus trituberculatus shells. And another viscosity chitosan were prepared from chitin which were deacetylated under various concentration of alkali, reaction time and temperature by the application of Mima's method. And crosslinked chitin/chitosan was preparaed from chitin/chitosan with crosslink agent followed by crosslinkage. The major parameters for chitosan manufacturing methods were found to be concentration of alkali solution, reaction time and temperature etc. The effects of these parameters on chitin, another viscosity(molecular weight) chitosan and crosslinked chitin/chitosan were investigated by various analysis apparatus.

• 한국응용과학기술학회지
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• 제16권4호
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• pp.293-298
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• 1999

Dual-action agents are unique chemical entities comprised of two different types of antibacterial compounds covalently linked together in a single molecule in such a way that both components are able to exert their bactericidal properties. Crosslinked sulfadiazine-sulfacetamide such as antibiotics synthesized by crosslingking reaction such as glutaraldehyde. These structures of the compounds were confirmed by IR, NMR. 4 strains of Gram(+) and Gram(-) revealed effective susceptibility to synthetic crosslinked sulfadiazine-sulfacetamide.

• 방사선산업학회지
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• 제2권3호
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• pp.105-110
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• 2008

Poly (VDF-co-HFP)/PEGDMA nanofibrous membranes (NFMs) have been prepared by an electrospinning process. Since electrospun NFMs have a nanoporous structure, they have a potential application for a polymer electrolyte or a separator. Poly (VDF-co-HFP) is a polymer electrolyte binder. In order to improve their mechanical properties, poly (VDF-co-HFP)/PEGDMA NFMs were crosslinked by a gamma-ray irradiation. Then the crosslinked NFMs were characterized through an electrolyte uptake, IR structural analysis, and SEM morphological investigation.