• Bulletin of the Korean Chemical Society
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• 제35권6호
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• pp.1665-1669
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• 2014

Four multialkoxy-functionalized siloxane base-polymers (BP-1~4) were synthesized through either hydrosilylation or condensation reactions in order to prepare multi-networked siloxane polymers having appropriate physical properties for protective coating in fabrications of electronics. Formulations of 4 base-polymers gave coating materials A and B. Product A showed well-controlled flowing and leveling properties, and product A-2 was successfully applied to protective insulating coating for junction areas of connectors and chips in PDP controller. Tack free time, extrusion rate, dielectric breakdown voltage, hardness, thermal stability, water resistance and flame resistance of products A and B were examined.

• 한국수의병리학회:학술대회논문집
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• 한국수의병리학회 2003년도 추계학술대회초록집
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• pp.19-19
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• 2003

Osteoporosis is usually considered a disease of older women reported the rate, pattern and determinants of bone loss, far less information is available for men although it is also common in men [1,2]. The three major causes of osteoporosis in men are excessive alcohol intake, long-term glucocorticoid therapy, and hypogonadism [3,4]. In process of bone resorption, type I collagen crosslinking molecules, pyridinoline (PYD) are released into the circulation and cleared by the kidney. $^2$H$_2$O as a tracer has been applied to measure synthesis rates of slow-turnover proteins and successfully applied to bone collagen synthesis, skeletal muscle and cardiac muscle in rat. The objective of this study was to examine osteoporosis and alcohol-induced changes of femur and liver in post-menopausal males using the developed method. (omitted)

• Journal of Pharmaceutical Investigation
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• 제22권1호
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• pp.23-31
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• 1992

A novel O-diethylaminoethyl chitosan (DEAE-chitosan) was synthesized via Schiff's reaction between chitosan and benzaldehyde. $C_2$ amino group was protected via Schiffs base reaction with benzaldehyde to form N-benzylidene chitosan. After reaction with diethylaminoethyl chloride, Schiffs base was removed by reacting O-diethylaminothyl-N-benzylidene chitosan and hydrochloric acid. Tensile strength of DEAE-chitosan was improved due to the incorporation of bulky side group in $C_6$ position of chitosan. DEAE-chitosan showed a pH-dependent swelling characteristics. Release rate of riboflavin was dependent on the water content of DEAE-chitosan that is a function of crosslinking degrees.

• 환경위생공학
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• 제11권3호
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• pp.13-19
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• 1996

Packed bed reactor containing immobilized microorganisms which degraded phenol without growth was used to remove phenol from the synthetic wastewater. The effects of temperature, retention time(reactor volume/flow rate) and phenol concentration on the removal efficiency of phenol were investigated. The effect of temperature in the range of 20-30$\circ $C was negligible while retention time and phenol concentration influenced the removal of phenol significantly. When retention time was in the range of 1-1.5 hour, the removal efficiency of phenol was affected not by phenol concentration but by retention time itself while it was influenced by phenol concentration above 1.5 hour of retention time. The beads after 720 hours operation were swelled by 40 % in diameter which could be prevented by crosslinking with glutaraldehyde at the expense of cell activity.

• 한국의류학회지
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• 제23권3호
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• pp.414-422
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• 1999

The purpose of this study is to develop multifunctional fabric that was improved antimicrobial activity and reduction rate of gas by treatment of mixture that was blended chito colla ad crosslinking material for Nylon. Antimicrobial activity was proved 99% reduction rat of gas in case of treated was icreased. The surface of treated fiber noted harshness and irregularity. Whiteness of treated on the baking condition was decreased as time and temperature was increased. Air permeability and moisure regain of treated equally was maintained. Water absorption and static voltage of treated were increased. KOSHI and T.H.V. of treated was increased than that of untreated B/W of treated was improved that, that of untreated and 2HB/B. W/T of treated were reduced.

• 한국염색가공학회지
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• 제11권4호
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• pp.31-38
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• 1999

The purpose of this study is to develop multifunctional fabric that has improved antimicrobial activity and reduction rate of gas by treatment of mixture of chito colla and crosslinking material for polyester. The surface morphology of treated PET fabric was studied by scanning electron microscopy(SEM). The properties of the PET fabric, such as antimicrobial activity, whiteness, moisture regain, water absorption and static voltage, and handle were investigated. Antimicrobial activity of treated PET fabric was proved 99%. The surface of treated PET fabric showed harshness and irregularity. The whiteness of treated PET fabric on the baking condition was decreased as time and temperature was increased. The moisure regain of treated PET fabric equally was maintained. Water absorption and static voltage of treated PET fabric were improved. KOSHI of treated PET fabric was increased compared with the untreated PET fabric H/W of treated PET fabric was improved compared with the untreated PET fabric and 2HB/B of treated PET fabric were reduced.

• Bulletin of the Korean Chemical Society
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• 제4권3호
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• pp.128-132
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• 1983

The self-diffusion experiment of water was performed across two series of tactic poly(2-hydroxyethyl methacrylate), P(HEMA) membranes prepared by crosslinking with various amount of hexamethylene diisocyanate (HMDIC). The tagging material was tritium hydroxide (THO) and the efflux of THO was counted on a Liquid Scintillation Counter. The transport data of THO show that the permeability decreases as the amount of HMDIC increased from 2.5 to 10 mole % and the self-diffusions coefficient shows a parallel trend with it. The diffusivity data was discussed in terms of the change of water structural orderliness within membranes. Using the relation between viscosities and diffusivities derived from Eyring's absolute rate theory, the corresponding viscosities of water within two series of tactic P(HEMA) membranes were obtained. From this, it is seen that the viscosity of water within tactic P(HEMA) membranes may have the same values with those of supercooling water whose temperature ranges from -28 to -$36^{\circ}C.$.

• Biomaterials and Biomechanics in Bioengineering
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• 제4권1호
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• pp.1-8
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• 2019

The aim of this study was to investigate the effect of total polymer concentration on the chemical structure, morphology of pores, porosity, swelling ratio, degradation of gelatin-poly (vinyl alcohol) (Gel-PVA) cryogel scaffolds. Porous cryogels were prepared with cryogelation technique by using glutaraldehyde as a crosslinker. Functional group composition of cryogels after crosslinking was investigated by Fourier Transform Infrared (FTIR). The morphology of cryogels was characterized via scanning electron microscopy (SEM) and porosity analysis. All of the cryogels had a porous structure with an average pore size between $45.58{\pm}14.28$ and $50.14{\pm}4.26{\mu}m$. The cryogels were biodegradable and started to degrade in 14 days. As the polymer concentration increased the swelling ratio, the porosity and the degradation rate decreased. Spongy and mechanically stable Gel-PVA cryogels, with tunable properties, can be potential candidates as scaffolds for tissue engineering applications.

• Corrosion Science and Technology
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• 제8권5호
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• pp.197-202
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• 2009

The high toxicity of wax, oil, varnish and volatile corrosion inhibitor(VCI) corrosion inhibitors lead to an increasing interest in using non-toxic alternatives such as anti-corrosive film. This study aims to investigate the possibility to use acryl based anti-corrosive film as a substitution of toxic corrosion inhibitors. Acryl emulsions were polymerized by several acryl monomers(acrylonitrile(AN), n-butyl acrylate(nBA), methylmethacrylate(MMA) and glycycyl methacrylate(GMA)), non-toxic corrosion inhibitor, crosslinking agents(diethylene glycol dimethacrylate(DEGDA)) and various additives in order to apply substrate of anti-corrosive film. Acryl emulsion for anti-corrosive film(AeACF) as a substrate of corrosion inhibitor film has excellent removal characteristic at above $25^{\circ}C$. The crosslinked by DEGDA in a range of above 4 wt% content anti-corrosive film can easily remove from the metal surface by using hands because it kept a balance of cohesion and adhesion strength. Anti - corrosive performance of AeACF is better than anti-corrosive oil by corrosion rate test, which was measured $54.3mg/dm^2$ day(MDD) and $142.9mg/dm^2$ day, respectively. Anti-corrosive film consisting of acryl monomers and inorganic anti-corrosive ingredients did not emit any toxic pollutants by gas chromatography. Thus it is estimated that acryl based anti-corrosion film can substitute toxic corrosion inhibitors.

• Asian-Australasian Journal of Animal Sciences
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• 제18권12호
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• pp.1794-1799
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• 2005

The present study was carried out to develop crosslinking of $\beta$-cyclodextrin ($\beta$-CD) using adipic acid, and to determine the optimum conditions of different factors ($\beta$-CD concentration, mixing temperature, mixing time and mixing speed) on cholesterol reduction from homogenized milk. Crosslinked $\beta$-CD was prepared with adipic acid. When the milk was treated with different conditions, the cholesterol removal rate was in the range of 92.1 to 93.1% with 1% $\beta$-CD addition, which were not significantly different among treatments. After cholesterol removal from milk, the used crosslinked $\beta$-CD was washed for cholesterol dissociation and reused. For recycling study, the cholesterol removal rate in the first trial was 92.5%, which was mostly same as that using new crosslinked $\beta$-CD. With repeated ten time trials using same sample, 81.4% of cholesterol was removed from milk. Therefore, the present study indicated that the optimum conditions for cholesterol removal using crosslinked $\beta$-CD were 1% $\beta$-CD addition and 10 min mixing with 400 rpm speed at 5$^{\circ}C$ with over 90% cholesterol removal. In addition, crosslinked $\beta$-CD made by adipic acid resulted in the effective recycling efficiency.