• Proceedings of the Korean Institute of Building Construction Conference
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• 2013.11a
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• pp.106-107
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• 2013

The purpose of this study is to characterize the bonding properties between reinforced bar and re-emulsion polymer cement mortar through the pull off test. The properties of polymer cement mortar before and after hardening were measured. Spiral reinforced steel bar was used to control the brittleness fracture of test specimens. In addition polymer content as experimental factors, the types of reinforced bar and corrosion were considered as well. Non linear FEM analysis was carried out to expect the behavior of bonding interface under the certain load.

• Journal of the Korean Ceramic Society
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• v.26 no.3
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• pp.361-370
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• 1989

Mullite powders were synthesized from the common solution of aluminum sulfate and sodium silicate solutions by the emulsion-hot kerosene technique. The reaction temperature and mechanism for mullitization and the characteristics of synthesized mullite powders were investigated. The effect of Na components introduced from sodium silicate solution on the physical property and microstructure of sintered mullite was also examined. It was proved that mullites were formed at 75$0^{\circ}C$ through the reaction mechanism of Na2O.2.2SiO2＋3.3Al2(SO4)3longrightarrow1.1(3Al2O3.2SiO2)＋Na2SO4＋8.9SO3. Synthetic mullite powders consisted of the compositiion of 3Al2O3.2SiO2 and showed highly agglomeration of hollow spherical particles of 1${\mu}{\textrm}{m}$ diameter. The density and fracture toughness of sintered mullites were somewhat reduced because of the effect of a very small amount of residual Na components.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2019.11a
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• pp.133-134
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• 2019

As part of recent low-energy policies, thermal insulation standards for buildings are being tightened every year. The importance of external insulation methods is increasing due to the strengthening of insulation standards. Among the main materials used in the external insulation method, dry bit material is a finishing material composed of an organic binder and aggregate. When the fire occurs, the ignition of the surface part causes a direct fire on the thermal insulation material at the rear side when heat energy is concentrated. Therefore, it is important that the finishing material in dry insulation using a dry bit has a low fire spreading property in case of a fire and does not have a sustained combustion. The purpose of this study was to evaluate the fire spreadability by changing the internal fillers while using alkoxide-based acrylic emulsions, hybrid acrylic emulsions, and general acrylic emulsions in order to suppress the fire spreading properties of exterior finish materials.

• Journal of the Korean Applied Science and Technology
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• v.28 no.3
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• pp.359-366
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• 2011

In this study we experimented that how polyurethane effect to acrylic-polyurethane resin in Full-Grain leather coatings. First of all, we consummated waterborne acrylic emulsion and waterborne polyurethane resin, Than we prepared F.G leathers which were coated by acrylic resin and acrylic-polyurethane resins. According to measured data for solvent resistance, acrylic resin and acrylic-polyurethane resins had good property. Sample a(WAC) had most low strength($2.10kg_f/mm^2$) and sample d(WAC 93 : WPU 7) had most high strength($3.41kg_f/mm^2$). Also we knew that most good property of abrasion is d(47.4 mg). In elongation case, a(WAC) had most good result(645 %) in this experiment.

• Journal of the Korean Society of Food Science and Nutrition
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• v.28 no.1
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• pp.167-171
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• 1999

The production of emulsion sausage generally contain nitrite as a curing agent for preservative effect and color as well as flavor development. This investigation describe a study on the inhibitory effect of chitosan against some spoilage bacteria and substitution effect of nitrite in sausages. Among of the chitosan, M.W. 120KDa of chitosan has shown an antimicrobial effect. When 0.2% of chitosan and half of normal nitrite content were added to sausage, effect of preservative quality was same that added to normal content of nitrite in sausages. Sausage added to 0.5% of chitosan has been a good storage property even though without nitrite. The growth of most of bacteria was inhibited 80% or more at 0.01~0.2% of chitosan. These results indicated that M.W. 120KDa of chitosan as a natural material could provide sausage protection and very reduced or substituted amount of nitrite against spoilage bacteria.

• Journal of the Korean Wood Science and Technology
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• v.35 no.1
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• pp.44-50
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• 2007

The objective of this study was to investigate the influence of the vehicle resin on the coating performance of Dan-Chung. The starch glue (F), fish glue (G), and aqueous acrylic resin emulsion (E) were used as vehicle resins. Panels coated with Dan-Chung were tested at accelerated weathering and outdoor conditions. Aqueous acrylic resin was proved as an excellent vehicle resin for Dan-Chung, because there was no flaking in Dan-Chung film after accelerated weathering and outdoor exposure. Discoloration of Dan-Chung using E was the smallest among the acceleratedly weathered panels. Adhesive property of Dan-Chung film using G was. remarkably improved by G-undercoating. On the contrary, G-undercoating lowered adhesive property of Dan-Chung film using E.

• Journal of the Korean Applied Science and Technology
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• v.32 no.3
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• pp.469-479
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• 2015

This study is related to the developing method of a transparent sunscreen cosmetic which has waterproofing property and no white turbidity when applied to skin. The transparent sunscreen is prepared by exploiting refractive index difference between oil-phase and water-phase of water-in-oil(W/O) emulsion. The sunscreen according to this study is prepared as a W/O type emulsion so that it is water-stable and water resistance. Also, the stability of W/O type emulsion is developed by adjusting the content of oil phase part and water phase part. As a result of this studying, the transparent W/O emulsion is prepared by adjusting the refractive index of oil-phase and water-phase within 0.004 and it is found that the stability of the transparent sunscreen is increasing when the water phase part is over 75% (w/w) of the W/O emulsion. Through clinical test of transparent sunscreen, the value of sun protection Factor(SPF) and Protection Factor of UVA(PFA) were determined. SPF and PFA values of transparent sunscreen were indicated $30.99{\pm}1.65$ and $3.01{\pm}0.30$.

• Applied Chemistry for Engineering
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• v.16 no.1
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• pp.81-85
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• 2005

Pressure sensitive adhesive (PSA) was prepared by semi-batch emulsion polymerization of acryl monomers in the presence of reactive and non-reactive carboxylated polyurethane resin (PUR). Effects of the PUR type, its content, and crosslinker feeding method on the adhesive properties of the PSA was investigated. In this experiment, the PSA prepared with the reactive PUR showed better adhesive property then the PSA with the non-reactive PUR. Especially, peel strength of the PSA, where acetoacetoxy ethyl methacrylate and 1,6-hexane diamine as crosslinkers were introduced, was dramatically enhanced in severe humidity condition due to the interfacial crosslinking.

• Journal of the Korean Applied Science and Technology
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• v.13 no.3
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• pp.61-71
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• 1996

In acid-catalyzed acetal cyclization of long aliphatic aldehydes($R=n-C_7H_{15}$ ; $n-C_9H_{19}$ ; $n-C_{11}H_{23}$) with 1,1,1-tris(hydroxymethyl)propane, 2-alkyl-5-hydroxymethyl-5-ethyl-1,3-dioxanes were obtained. The final products, sodium 2-alkyl-5-(sulfonatedpropylethermethyl)-5-ethyl-1,3-propanesultion in the presence of sodium hydride. These compounds were a new group of destructible surfactants which were readily hydrolyzed and oxidized in natural water reservoirs. Physical properties of these new compounds involved some surface properties such as Krafft point(Kp), critical micelle concentration(cmc), surface tension of aqueous solutions near cmc(${\gamma}_{min}$), foaming power, emulsion power and hydrolysis properties were determined. The destructible surfactants containing 1,3-dioxane ring were synthesized to about $85{\pm}5.5%$ yield. The cmc values of the compounds by ring method were assumed to $0.5{\sim}5.0{\times}10^{-3}mol/L$ range and surface tensions at cmc were $29.5{\sim}33.0dyne/cm$ respectively at $25^{\circ}C$. The foaming power and foam stability were $170{\sim}230mm$ and $52{\sim}135mm$ respectively at $1{\times}10^{-2}mol/L$, foam was occurred rarely below $1{\times}10^{-3}mol/L$. The emulsion property of liquid paraffin was better than that of soybean oil. For hydrolysis property with ph and time, these compounds were decomposed within about 200minutes at $ph1{\sim}2$. Hopefully these compounds are expected to be a good O/W emulsifier that have decomposability in acid and may be used in the process which do not need foaming.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.43 no.1
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• pp.27-33
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• 2017

Up to now, better convenience and portability were important factors in the development of the cosmetics and achieved by immersing low viscosity makeup water-in-oil (W/O) emulsion into the impregnation material. Conventionally, polyurethane sponges having porous network structures and hard textures have been dominantly used. It has an advantage of easy to manufacture because of its good impregnation property due to its structural characteristics. However, it releases emulsion too much at first use, and shows unexpected dramatic decline during the period of usage. In this study, we studied on makeup W/O emulsion with various features and developed the new foaming sponge, which showed excellent formability and proper absorption and discharge ability of cosmetic composition through the combination of natural rubber (NR) and styrene butadiene rubber (SBR). This impregnation material is characterized by the softness of elasticity like a rubber, high elongation and uniform output. We confirmed that this material can be used to develop makeup products using various oils depending on polarity and controlling the viscosity of the makeup W/O emulsion. Thus, it is concluded that these results provide valuable information in developing new cosmetics impregnation materials.