• Journal of Integrative Natural Science
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• v.11 no.1
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• pp.1-8
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• 2018

HEMA, AA, MMA, and EGDMA as crosslinking agent and AIBN as an initiator, and 2,4-dihydroxybenzophenone, 2-ethylhexyl-trans-4-methoxy-cinnamate, 2-hydroxy-4-(methacryloyloxy)benzophenone as additives at 0.1-1.0% ratios were used to manufacture hydrophilic ophthalmic lenses through thermal polymerization before their physical properties were measured. The results showed that the samples containing of 2,4-dihydroxybenzophenone and 2-ethylhexyl-trans-4-methoxy-cinnamate resulted in a decrease of the UV blocking performance after high-pressure sterilization whereas the sample containing 2-hydroxy-4-(methacryloyloxy)benzophenone showed no change in the UV blocking performance. It is judged that this is induced by presence or absence of an acyl functional group in benzophenone.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2017.11a
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• pp.103-104
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• 2017

This paper is to provide a method to prevent air loss of the concrete using reject ash based ternary blended aggregate due to absorption of AE agents by reject ash by adding AE agents into reject ash before mixing concrete. Test results indicate that air loss due to presence of reject ash in ternary blended aggregate can be recovered by over use of AE agents into aggregate directly before mixing.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• v.9 no.2
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• pp.582-584
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• 2005

폭발적인 인터넷 사용자 수의 증가와 더불어 다양한 서비스들이 생겨나고 있으며, 인스턴트 메시징과 프레즌스 서비스는 대다수의 인터넷 사용자들이 사용하고 있는 서비스일 것이다. 대부분의 인스턴트 메시징과 프레즌스 서비스는 독자적인 프로토콜을 사용하여 구현되어 왔기 때문에 서비스 간의 연동이 매우 어려운 실정이다. 본 논문에서는 이러한 문제를 해결하기 위하여 IETF(Internet Engineering Task Force)에서 개발된 표준 기술에 대하여 살펴보고, 이를 바탕으로 구현된 SIP 기반 IMPP 사용자 에이전트를 소개한다.

• Transactions on Electrical and Electronic Materials
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• v.18 no.4
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• pp.203-206
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• 2017

The effect of the content of microsilica and nanosilica continuously modified with hydroxy silane and epoxy-modified silicone in cycloaliphatic epoxy/microsilica/nanosilica composites (EMNCs) on the mechanical and water repellent properties was evaluated. Surface-modified micro- and nanosilica was well-mixed with a cycloaliphatic epoxy resin in the presence of polyester-modified polydimethylsiloxane (PEM-PDMS) as a dispersing agent using an ultrasonicator. Tensile and flexural tests were carried out using a universal testing machine (UTM). The water repellent property was evaluated by contact angle measurements of water on the composite surface. Tensile strength of the composite could be enhanced by 32.2% up to 91.4 MPa, and the flexural strength was raised to 122.0 MPa, which is 38.8% higher than that of neat epoxy. The contact angle of water on the composite was as high as $104.1^{\circ}$.

• Biomolecules & Therapeutics
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• v.8 no.3
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• pp.248-254
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• 2000

(R)-JG-381, a R form of alkylglycidic acid derivative, was examined for mutagenicity in the reverse mutation test on bacteria, chromosomal aberration test on cultured mammalian cells and micronucleus test in mice. In the reverse mutation test on bacteria using Salmonella typhimurium strain TA98, TA100, TA102, TA1535, TA1537 with or without a metabolic activation system (S9 mix), (R)-JG-381 did not affect the revertant colonies but significantly increased revertant colonies in one test strain, TA98, compared with the vehicle control. In the chromosomal aberration (CA) test using cultured Chinese Hamster Lung fibroblast(CHL) cells, the number of aberrant cells was clot increased in the presence or absence of 59 mix at concentration of the (R)-JG-381 0.025 $\mu$l/m1 to 0.1 $\mu$l/m1, compared with vehicle control. In the micronucleus (MN) test, micronucleated polychromatic erythrocytes in the (R)-JG-381-treated mice were not different from those of the vehicle-treated mice.

• Archives of Pharmacal Research
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• v.25 no.4
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• pp.500-504
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• 2002

Propolis, obtained from honeybee hives, has been used in Oriental folk medicine as an anti-inflammatory, anti-carcinogenic, and immunomodulatory agent. There is considerable evidence suggesting that angiogenesis and chronic inflammation are codependent. Blockage of angiogenesis results in an anti-inflammatory effect. Ethanol (EEP) and ether extracts of propolis (REP), and caffeic acid phenethyl ester (CAPE), an active component of propolis, were examined for their anti-angiogenic activities using the chick embryo chorioallantoic membrane (CAM), and the calf pulmonary arterial endothelial (CPAE) cell proliferation, assays. The presence of EEP, REP and CAPE inhibited angiogenesis in the CAM assay and the proliferation of CPAE cells. The results suggest that anti-angiogenic activities of EEP, REP and CAPE are also responsible for their anti-inflammatory effect.

• Korean Journal of Chemical Engineering
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• v.35 no.12
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• pp.2379-2383
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• 2018

We report a facile one-pot aqueous-phase synthesis of PdAu bimetallic nanoparticles with different Pd/Au ratio. The synthesis was conducted by co-reduction of Pd and Au precursor using ascorbic acid as a reducing agent and in the presence of polyallylamine hydrochloride (PAH). By high-angle annular dark field scanning transmission electron microscopy (HAADF-STEM) and energy-dispersive X-ray spectrometry (EDS) analyses, we found that the synthesized nanoparticles had an onion-like core/shell/shell/shell structure with Au-rich core, Pd-rich shell, Au-rich shell, and Pd shell, respectively. We also investigated the catalytic performance of the synthesized PdAu nanoparticles toward hydrogen peroxide generation reaction.

• Bulletin of the Korean Chemical Society
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• v.22 no.6
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• pp.565-569
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• 2001

The spectral correction matrix has been established to study the simultaneous complextions between metals and a ligand, and it eliminated the mutual influence among the complexes. The two sensitive reations between iron(Ⅱ) and 1-(6-bromo-2-benzothiazolylazo)-2-naphthol(BBTAN) and zinc (Ⅱ) and BBTAN have been investigated and applied to the simultaneous determination of Zn and Fe at pH 8.5 in the presence of triton x-100. This method gave the simples determination of the characteristic constants of the complexes. For the analysis of natural water, foods and other samoles, the recoveries of Fe and Zn were between 92 and 109% and between 91 and 104%, and their relative standard deviations were less than 5.5 and 11%, respectively.

• Rubber Technology
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• v.5 no.2
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• pp.94-103
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• 2004

The present work describes modification of dual phase filler by electron beam irradiation in presence of multifunctional acrylates like trimethylol propane triacrylate (TMPTA) or silane coupling agent like bis (3-triethoxysilylpropyltetrasulphide) and in-fluence of the modified fillers on the physical properties of styrene-butadiene rubber (SBR) vulcanizates. Modulus at 300 % elongation increases whereas the tensile strength decreases with increase in radiation dose for the dual phase filler loaded styrene-butadiene rubber vulcanizates (SBR). However, modulus and tensile strength significantly increase, which is more, pronounced at higher filler loadings for TMPTA modified dual phase filler loaded SBR. These changes in properties are explained by the equilibrium swelling data and Kraus plot interpreting the polymer-filler interaction. Electron beam modification of the filler results in a reduction of tan ${\delta}$ at $70^{\circ}C$, a parameter for rolling resistance and increase in tan ${\delta}$ at $0^{\circ}C$, a parameter for wet skid resistance of the SBR vulcanizates. Finally, the influence of modified fillers on the properties like abrasion resistance, tear strength and fatigue failure and the improvement in the properties have been explained in terms of polymer-filler interaction.

• Journal of Electrochemical Science and Technology
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• v.10 no.2
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• pp.139-147
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• 2019

Incorporation of CuO nanoparticles during the polymerization of aniline in the presence of ammonium peroxydisulphate as an oxidizing agent and sodium salt of dodecylbenzene sulphonic acid as dopant as well as surfactant yielded water soluble CuO-PANI composite. Comparison of recorded spectra like FTIR, XRD and SEM with reported one confirm the formation of the composite. Analysis by gravimetric method exposes that the synthesized composite is having resistivity against corrosion, with slight variation in efficiency on extending the time duration up to eight hours in strong acidic condition. OCP measurement, potentiodynamic polarization and EIS studies also confirms the suppression ability of composite against corrosion. Riskless working environment could be provided by the synthesized composite during industrial cleaning process.