• Korean Journal of Fisheries and Aquatic Sciences
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• v.33 no.5
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• pp.378-382
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• 2000

The effects of bisphenol A (BPA), known as one of the endocrine disrupting chemicals (EDCs), on the hatching of fertilized eggs (FE) and the spawning of adult fish in songsari, Oryzias latipes were investigated. In condition of the experimental groups, incubated water temperature was $25.0{\pm}0.5^{\circ}C$ and photoperiod was 16 h (light) : 8 h (dark). fE were exposed to aqueous solutions of BPA at nominal concentration of 50, 100 and $200 {\mu}g/l$. The time required in hatching of FE was long in the BPA $50 and 100 {\mu}g/l$ treatment groups when compared to the controls, and in the BPA $200 {\mu}g/l$ treatment group, FE failed to hatch. And also hatching rate was decreased in the BPA treatment groups in comparison to the controls, Adult fishes were reared to oral administration via a diet of 50, 100 and $200 {\mu}g/g$ body weight BPA concentration for 3 weeks, Number of total eggs spawned in the adult fish were fewer in the BPA 100 and 200 treatment groups than in the controls and BPA 50 treatment group. Frequency of abnormal eggs in the total eggs spawned was 11.8 and $16.2{\%}$ in the control and acetone carrier control lower than 36.8, 46,8 and $74.1{\%}$ in the BPA 50, 100 and 200 treatment groups, respectively. And hatching rate of FE decreased in the BPA treatment groups in comparison to the controls. In these results, inhibition of the hatching of FE and the quantity and quality of spawned eggs in adult fish were observed from BPA treatment groups when compared to the controls.

• Journal of Conservation Science
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• v.26 no.1
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• pp.85-94
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• 2010

Color stable hydrogenated bisphenol-A (HBA) epoxy adhesives containing organic-inorganic hybrid nanocomposites were prepared and investigated the properties. Isophorone-diamine (IPDA) was used as a hardener and polyhedral organomeric silsesquioxanes (POSS; EP0408 and EP0409) having epoxy function groups were used to tailor adhesives in the nanoscale range. The dependence of the concentration of different nano materials were studied since the large surface area of the nanosized particles can cause significant changes in properties of adhesives. HBA-IPDA adhesives containing different amount of nanomaterials have been applied to the fresh Namsan granite and compared with those of commercial adhesives, which have problems of color change as well as a high viscosity. The mechanical properties of HBA-IPDA containing POSSs are consistent with those of commercial adhesives in addition to the low viscosity.

• Journal of the Korean Applied Science and Technology
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• v.35 no.3
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• pp.595-605
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• 2018

In recent years, researches on organic-inorganic coating films have conducted a nanocomposite system composed of organic resin matrices having excellent flexibility and chemical stability and inorganic materials having excellent mechanical properties. The o-phenylphenoxyethyl acrylate (OPPEA) used as the acrylate monomer has a high refractive index of 1.58, and the bisphenol A ethoxylate diacrylate (BAEDA) has a low refractive index but improves the chemical stability of the organic resin. In addition, zirconia used as an inorganic material exhibits excellent durability and optical properties. In this study, the BAEDA contents in acrylate monomer were controlled to produce a film with suitable optical transparency. And optimum conditions were established by comparing the changes in surface properties of PET films detected with pencil hardness tester, Abbe's refractometer, and UV-vis spectrophotometer. The hydrophobicity and the dispersibility of zirconia in acrylate monomer were much improved after modification with ${\gamma}$-methacryloxypropyltrimethoxysilane (MPS), which is a silane coupling agent. And the existence of ester C=O bond peak at $1716cm^{-1}$ introduced by MPS through FT-IR ATR spectrophotometer confirmed the completion of surface modification of zirconia with MPS. In addition, the presence of silicon atom on the surface modified zirconia was also proved using X-ray fluorescence spectrometer. When the photocurable hybrid coating was prepared by introducing chemically modified zirconia into acrylate monomer, the refractive index of this coated PET film was improved by 1.2%, compared to the only acrylate coated PET film. The homogeneous distribution of zirconia in acrylate coating layer on PET film was also identified through SEM/EDS mapping analysis technique.

• Applied Chemistry for Engineering
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• v.5 no.5
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• pp.904-909
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• 1994

Cure kinetics of DGEBA(diglycidyl ether of bisphenol A)/MDA(4,4'-methylene dianiline)/GN(glutaronitrile) system with and without HQ(hydroquinone) as a catalyst was studied by Kissinger equation and Fractional life method. The activation energy of the system with HQ was somewhat lower and the pre-exponential factor of that was higher by about 30% than those of the system without HQ. As 1.25phr of HQ was added, reaction rates increased about 1.8 times.

• Korea-Australia Rheology Journal
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• v.18 no.1
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• pp.1-8
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• 2006

Blend of bisphenol-A polycarbonate (PC) and (acrylonitrile-styrene-acrylic rubber) terpolymer (ASA) having excellent balance in the interfacial properties and mechanical strength was developed for the automobile applications. Since interfacial adhesion between PC and styrne-acrylonitrile copolymer (SAN) matrix of ASA is not strong enough, two different types of compatibilizers, i.e, diblock copolymer composed of tetramethyl polycarbonate (TMPC) and SAN (TMPC-b-SAN) and poly(methyl methacrylate) (PMMA) were examined to improve interfacial adhesion between PC and SAN. TMPC-b-SAN was more effective than PMMA in increasing interfacial adhesion between PC and SAN matrix of ASA (or weld-line strength of PC/ASA blend). When blend composition was fixed, PC/ASA blends exhibited similar mechanical properties except impact strength and weld-line strength. Impact strength of PCI ASA blend at low temperature was influenced by rubber particle size and its morphology. PC/ASA blends containing commercially available PMMA as compatibilizer also exhibited excellent balance in mechanical properties and interfacial adhesion.

• Advances in materials Research
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• v.5 no.3
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• pp.171-179
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• 2016

Fusion and characterization of bisphenol-A diglycidyl ether based thermosetting polymer mortars containing an epoxy resin, Fly ash and Rock sand are presented here for the Experimental study. The specimens have been prepared by means of an innovative process, in mild conditions, of commercial epoxy resin, Fly ash and Rock sand based paste. In this way, thermosetting based hybrid mortars characterized by a different content of normalized Fly ash and Rock sand by a homogeneous dispersion of the resin have been obtained. Once hardened, these new composite materials show improved compressive strength and toughness in respect to both the Fly ash and the Rock sand pastes since the Resin provides a more cohesive microstructure, with a reduced amount of micro cracks. The micro structural characterization allows pointing out the presence of an Interfacial Transition Zone similar to that observed in cement based mortars. A correlation between micro-structural features and mechanical properties of the mortar has also been studied.

• Proceedings of the KIEE Conference
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• 1987.11a
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• pp.499-503
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• 1987

The electrical characteristics of Epoxy Robin vary with temperature. In this study, the variation of the electric characteristics of Epoxy Resin with various hardening temperature was studied. Epoxy Resin used as samples are Epotohto YD-128 of Diglycidyl Ether of Bisphenol A (DGEBA) series and hardener, Goodmide G-240. It's mixing rate is 3 to 1. Hardening temperature was varied from 25[$^{\circ}C$] to 50[$^{\circ}C$] by 5[$^{\circ}C$]. During the hardening progress, illumination, resistivity and the internal temperature of material which were dependet on the variety of hardening temperature were measured. The electrical properties of hardened samples were examined by means of X-ray diffraction, tan $\delta$ test, TG-DTA analysis and treeing test. On this basis, optimal hardening temperature in insulation characteristics was examined.

• Bulletin of the Korean Chemical Society
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• v.34 no.4
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• pp.1225-1231
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• 2013

A novel class of hyperbranched polyesters, HPpEP and HPmEP, were prepared via a facile one-pot polymerization of a phloroglucinol (as a $B_3$ monomer) with a phthaloyl dichloride (as an $A_2$ monomer) for replacing a problematic BPA developer in thermal printing system. The resulting polymers, HPpEP and HPmEP, had highly branched structures and met well the requirements for high performance developer materials such as colorlessness, easy and inexpensive synthesis, high thermal stability, etc. In addition, these polymers exhibited an efficient reaction with leuco dyes (ODB-2) for a coloring process by releasing protons from linear and terminal phenol groups of polymers when heated.

• Journal of the Semiconductor & Display Technology
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• v.11 no.2
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• pp.23-26
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• 2012

The monodispersed polystyrene spheres were prepared by emulsion polymerization in aqueous alcohol system. They coated with silver by reduction of silver ion percolated on the surface of them. The spherical hollow type silver has been prepared by dissolving polystyrene with toluene. Epoxy resin compositions with spherical hollow type silver were manufactured, which were composed of a bisphenol F type epoxy resin (RE-304S), amine type hardener (Kayahard AA), and 1-benzyl 2-methyl imidazole (1B2MI) as catalyst. The electrical conductivity with silver content ratio were investigated after cure, the percolation threshold weight ratio for conductance in this epoxy resin system was obtained above the 70 wt% of silver.

• Journal of the Korean Society of Food Science and Nutrition
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• v.36 no.7
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• pp.825-831
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• 2007

Anti-proliferation effects of decursin from Angelica gigas Nakai were investigated in the MCF-7 cells treated with environmental hormones. The proliferation was decreased in a dose-dependent manner at the concentration over 20 ${\mu}g/mL$ in the MCF-7 cells treated with decursin of various concentrations. The environmental hormones such as $17{\beta}$-estradiol and bisphenol increased the growth of MCF-7 cells in the charcoal-treated FBS (cFBS) medium and the proliferation was the highest at 0.1 ${\mu}M$ among the tested hormone concentration. Decursin was predicted to inhibit the proliferation in a dose-dependent fashion at tested concentrations (1, 3, 10 or 30 ${\mu}g/mL$) in the MCF-7 cells added environmental hormones; however, the survival rate of the cells was lower than that of control cells that were not treated with decursin at 30 ${\mu}g/mL$ concentration. The chromatin condensation and apoptotic body were examined in the decursin treated cells cultured with the cFBS medium added environmental hormones. These results suggest that decursin decreased the proliferation through apoptosis in the MCF-7 cells added environmental hormones.