• Proceedings of the Korea Concrete Institute Conference
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• 2003.05a
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• pp.75-78
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• 2003

This study is to investigate the probability to develop the AE Water-reducing agent which can decrease the bleeding by mixing melamine type super-plasticizer(SP) and methyl cellulose(MC) viscosity agent. According to the result, as the mixing ratio of melamine type SP and MC viscosity agent increases, the bleeding is reduced due to a increase of the air content. When the mixing ratio of melamine type SP and MC viscosity agent is 1:2 and 1;3 at the water content of 165kg/$m^3$ and 175kg/$m^3$ respectively, slump and air content are satisfied and bleeding is reduced to some extent, so this is determined as the mixing ratio of AE water reducing agent for reduction of bleeding. It is prove that the developed AE water reducing agent for reduction of bleeding can reduce the amount of bleeding and prohibit the plastic shrinkage crack by slowing down the bleeding speed. Compressive strength of hardened concrete does not make any difference in comparison with plain concrete.

• Proceedings of the Korean Geotechical Society Conference
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• 2009.09a
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• pp.519-523
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• 2009

In this study, the base mixing ratio was determinated to estimate the optimal mixing ratio of material with a change of mixing ratio of micro cement, sand, foaming agent, plasticizer by testing the unconfined compressive strength test. The unconfined compressive strength test was performed to grasp a engineering characteristics of with a change of micro cement, bubble. The results of test, the unconfined compressive strength increased with a micro cement's increase and bubble's decrease. In the future, it will be secured that is reliable datas from laboratory of various condition and in-situ tests to develop optimal lightweight foamed concrete.

• Journal of Korean Ophthalmic Optics Society
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• v.18 no.1
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• pp.11-17
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• 2013

Purpose: To improve glasses temple's insert processibility of CA/PEG blend, triacetin with higher specific heat values in the processing temperature range is used as second plasticizer. Methods: The total amount of plasticizer is fixed at 30 wt% by CA. To determine optimal CA/PEG/triacetin blend for glasses frame, blends with different composition ratio were examined by various analysis: thermal properties, mechanical properties, glossiness. Results: Specific heat of the CA/PEG blend increased as the content of triacetin. In CA/PEG/triacetin blends, as triacetin concentration is increased, glass transition temperature is decreased and heat conservation rate of composites is increased. Furthermore, CA/PEG/triacetin blend exhibited higher mechanical properties and similar gloss characterization with CA/PEG blend. Conclusions: It is possible to improve the processibility inserting metal support to CA temple through varying the weight ratio of PEG/triacetin. The extruded sheets of CA/PEG/triacetin blend had better glossiness and mechanical properties than those of CA/PEG blend.

• Archives of Pharmacal Research
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• v.26 no.11
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• pp.973-978
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• 2003

A polymeric film composed of Carbopol, Poloxamer and hydroxypropyl methylcellulose was prepared to develop a buccal patch and the effects of composition of the film on adhesion time, swelling ratio, and dissolution of the film were studied. The effects of plasticizers or penetration enhancers on the release of triamcinolone acetonide (TAA) were also studied. The hydrogen bonding between Carbopol and Poloxamer played important role in reducing swelling ratio and dissolution rate of polymer film and increasing adhesion time. The swelling ratio of the composite film was significantly reduced and the adhesion time was increased when compared with Carbopol film. As the ratio of Poloxamer to hydroxypropyl methylcellulose increased from 0/66 to 33/33, the release rate of TAA decreased. However, no further significant decrease of release rate was observed beyond the ratio of 33/33. The release rate of TAA in the polymeric film containing polyethylene glycol 400, a plasticizer, showed the highest release rate followed by triethyl citrate, and castor oil. The release rate of TAA from the polymeric film containing permeation enhancers was slower than that from the control without enhancers. Therefore, these observations indicated that a preparation of a buccal patch is feasible with the polymeric film composed of Cabopol, Poloxamer and hydropropyl methylcellulose.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2015.11a
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• pp.103-104
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• 2015

This study is an experiment about what affects the compressive strength by using a reducing agent (PNS based admixtures) to play cement using the cement paste based Waste Concrete Powder of waste concrete, which accounts for more than 60% of construction waste around the latest domestic and international It was. Securing the replacement of cement with Waste Concrete Powder and, by varying the admixture was to compensate for the low absorption of liquidity and obtain a fine powder. And the experiment was conducted with a constant water cement ratio and aggregate usage for the purpose of lowering the water cement ratio promoting strength development. When substituted with the experimental results of 0.3% based on 3 ~ 28 days as strength 36Mpa exhibited the highest strength.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1998.11a
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• pp.121-124
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• 1998

The purpose of this study is to research and develop solid polymer electrolyte(SPE) for Li secondary battery. This paper describes temperature dependence of conductivity, impedance spectroscopy, electrochemical properties of PVDF electrolytes as a function of a mixed ratio. Polyvinylidene(PVDF) based polymer electrolyte films were prepared by thermal gellification method of preweighed PVDF, plasticizer and Li salt. The conductivity of PVDF electrolytes was 10$\^$-3/S/cm. 25PVDFPC$\_$10/EC$\_$10/LiClO$_4$ electrolyte shows the better conductivity of the others. 25PVDFPC$\_$10/EC$\_$10/LiClO$_4$electrolyte remains stable up to 4.7V vs. Li/Li$\^$+/. Steady state current method and ac impedance used for the determination of transference numbers in PVDFD electrolyte film. The transference number of 25PVDFPC$\_$10/EC$\_$10/LiClO$_4$electrolyte is 0.58.

• Journal of the Korean Ceramic Society
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• v.44 no.10
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• pp.548-553
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• 2007

Ceramic green sheets consisting Bi-based glass frit were fabricated for an application to PDP transparent dielectric front panel. The dispersion condition of the slurry for tape casting was pre-examined, and two kinds of hinder and plasticizer were used in the non-aqueous slurry system. In the fabrication process for the frit film, the properties such as dry and firing shrinkage, elongation, and transmittance were examined at the condition of various mixing ratio of plasticizers. In the mixing ratio of polyethylene glycol to dibutyl phthalate of 3:5wt%, a good adhesion, elongation and transmittance were observed at the firing temperature of $580^{\circ}C$. The photograph for the cross section of the interface was also showed a dense microstructure.

• Proceedings of the Korea Concrete Institute Conference
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• 1995.10a
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• pp.113-118
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• 1995

The purpose of this study is to suggest concrete mix proportioning design using Blast-furnace slag cement. The mix conditions are specified by concrete strength(180~400kg/$\textrm{cm}^2$), slump$(15\pm2cm)$m and air volume$(4.5\pm1%)$. From the result of concrete mix proportioning design using Blast-furnace slag cement, unit water content can be reduced by 3~8% comparing with OPC. The relationship between strength at 28days and cement water ratio is as follow. when blast-furnace slag cement is used: $\sigma_{28}$=304.OC/W-296.8. Super-plasticizer have to be used to get a slump of 15cm when water/cement ratio is less than 45%.

• Journal of the Korean Ceramic Society
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• v.38 no.11
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• pp.1060-1066
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• 2001

Water-based alumina tapes for application of all-ceramic crowns were fabricated using PVP as binder that is biocompatible, highly soluble in solvents, and no residue leftafter firing. Tensile strength of alumina tapes was governed by binder/(binder+plasticizer)ratio. On the other hand, linear shrinkage and density were determined by alumina/(alumina+organic) ratio. Composite for all-ceramic crowns, prepared by infiltration of a glass into sintered porous alumina, showed high flexural strength which increased with increasing sintered density.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.26 no.1
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• pp.33-37
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• 2013

The properties of LTCC green sheets formed by the MLS-22 powder of NEG Inc. were investigated for acrylic binders with different PVB and Tg in the variation of temperature. The elongation of the green sheets showed large variation depending on the temperature, and was rapidly decreased near the Tg of the sheets. With the increase of the ratio of plasticizer/binder (P/B), large elongation of the sheets was observed due to the decrease of the Tg. In the stacking process of the multilayer ceramic, the optimal control of the temperature is highly required depending on the Tg of the binder and the ratio of P/Buniform coating.