• Journal of the Korea Concrete Institute
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• v.19 no.5
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• pp.539-547
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• 2007

The effects of binder and alumina content on the setting time, drying shrinkage, strength, freezing and thawing resistance and water absorption of polymer-modified pastes with alumina powder were examined. As a result the setting time of the polymer-modified pastes with alumina powder tended to delay with increasing binder content. Irrespective of the type of polymer, the drying shrinkage of the polymer-modified pastes with alumina powder tended to decrease with increasing binder content and alumina powder content. Regardless of the type of polymer, the tensile and adhesion strengths of the polymer-modified pastes with alumina powder tended to increase with increasing binder content and alumina powder content. Irrespective of the type of polymer, the durability factors of the polymer-modified pastes with alumina powder tended to increase with increasing alumina content. Irrespective of the type of polymer, the water absorptions of the polymer-modified pastes with alumina powder tended to decrease with increasing binder content and alumina content.

• Journal of the Korea Concrete Institute
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• v.25 no.6
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• pp.657-665
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• 2013

The purpose of this study is the basic research of self-compacting concrete using Alkali-Activated Slag (AAS) binder in order to emphasize the durability of structures and facilitate casting the fresh concrete in field. The AAS binder emitted low carbon dioxide ($CO_2$) is eco friendly material of new concept because AAS products not only emit little $CO_2$ during production but also reuse the industrial by-products such as ground granulated blast-furnace slag (GGBS) of the steel mill. Until now, almost of domestic and foreign research are using Ordinary Portland Cement (OPC) for self-compacting concrete, and also, nonexistent research about AAS. The self-compacting concrete must get the performance of flowability, segregation resistance, filling and passing ability. Nine concrete mixes were prepared with the main parameter of unit amount of binder (400, 500, 600 $kg/m^3$) and 3 types of water-binder (W/B) ratio. The results of test were that fresh concretes were satisfied with flowability, segregation resistance, and filling ability of JSCE. But the passing ability was not meet the criteria of EFNARC because of higher viscosity of AAS paste than OPC. This high viscosity of AAS paste enables the manufacturing of self compacting concrete, segregation of which does not occur without the using of viscosity agent. It is necessary that the development of high fluidity AAS binders of higher strength and the study of better passing ability of AAS concrete mixes in order to use self compacting AAS concrete in field.

• Proceedings of the Korean Vacuum Society Conference
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• 2016.02a
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• pp.160-160
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• 2016

In this study, we applied the low temperature curing Ag paste to replace PVD System. The electrode formation of low temperature curing Ag paste for silicon Hetero-junction solar cells is important for improving device characteristics such as adhesion, contact resistance, fill factor and conversion efficiency. The low temperature curing Ag paste is composed various additives such as solvent, various organic materials, polymer, and binder. it depends on the curing temperature conditions. The adhesion of the low temperature curing Ag paste was decided by scratch test. The specific contact resistance was measured using the transmission line method. All of the Ag electrodes were experimented at various curing temperatures within the temperature range of $160^{\circ}C-240^{\circ}C$, at $20^{\circ}C$ intervals. The curing time was also changed by varying the conditions of 10-50min. In the optimum curing temperature $200^{\circ}C$ and for 20 min, the measured contact resistance is $19.61m{\Omega}cm^2$. Over temperature $240^{\circ}C$, confirmed bad contact characteristic. We obtained photovoltaic parameter of the industrial size such as Fill Factor (FF), current density (Jsc), open-circuit voltage (Voc) and convert efficiency of up to 76.2%, 38.1 mA/cm2, 646 mV and 18.3%, respectively.

• Computers and Concrete
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• v.8 no.3
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• pp.279-292
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• 2011

The main purpose of this study includes investigation of the rheological properties of fresh self consolidating cement paste containing chemical and mineral additives using Artificial Neural Network (ANN) model. In order to develop the model, 200 different mixes are cast in the laboratory as a part of an extensive experimental research program. The data used in the ANN model are arranged in a format of fourteen input parameters covering water-binder ratio, four different mineral additives (calcium carbonate, metakaolin, silica fume, and limestone), five different superplasticizers based on the poly carboxylate and naphthalene and four different Viscosity Modified Admixtures (VMAs). Two common output parameters including the mini slump value and flow cone time are chosen for measuring the rheological properties of fresh self consolidating cement paste. Having validated the model, the influence of effective parameters on the rheological properties of fresh self consolidating cement paste is investigated based on the ANN model outputs. The output results of the model are then compared with the results of previous studies performed by other researchers. Ultimately, the analysis of the model outputs determines the optimal percentage of additives which has a strong influence on the rheological properties of fresh self consolidating cement paste. The proposed ANN model shows that metakaolin and silica fume affect the rheological properties in the same manner. In addition, for providing the suitable rheological properties, the ANN model introduces the optimal percentage of metakaolin, silica fume, calcium carbonate and limestone as 15, 15, 20 and 20% by cement weight, respectively.

• Applied Chemistry for Engineering
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• v.10 no.8
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• pp.1114-1118
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• 1999

Barrier rib for the plasma display panel(PDP) was made by photolithographic process utilizing photosensitive barrier rib paste. The barrier rib paste was prepared by first dissolving ethylcellulose(binder polymer) in butyl carbitol(BC)/butyl carbitol acetate(BCA) =30/70 wt % mixture solvent at 15 wt % concentration. To this solution a mixture of functional monomers consisted of tripropyleneglycol diacrylate/ pentaerythritol triacrylate = 50/50 wt %, Irgacur 651 photoinitiator, and barrier rib powder were added and then the whole mixture was mixed in the three roll mill for 2 hr. The effect of component and concentration of photosensitive barrier paste on the photolithographic process was studied. After optimization of the paste formulation and photolithographic process, barrier rib could be obtained with good resolution up to $100{\mu}m$ height.

• 한국신재생에너지학회:학술대회논문집
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• 2007.06a
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• pp.320-322
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• 2007

A new binder-free $TiO_{2}$ paste was prepared by common ion applying effect, enabling low temperature fabrication required for flexible solar cells. The binder-free and high viscosity $TiO_{2}$ coating solution was produced by adding 7.5% aniline in $TiO_{2}$ colloid solution obtained from the high pressure water-heat response method. The resulting pastes had high level of viscosities proper for optimal coating and thus revealed excellent performances in terms of thickness uniformity and I-V characteristics.

• Proceedings of the Korea Concrete Institute Conference
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• 1997.10a
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• pp.369-374
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• 1997

This study is the experimental results on the flowing properties of the super flowing concrete (SFC) using limestone (LS), which is to develop the SFC in level of ordinary strength. And this study is described with respect to basic concept, confined water ratio ($\beta_p$) of binder (cement+limestone) in paste, relationship between volume ratio of water-binder (w/b) and addition ratio of superplasticizer in mortar, flowing velocity and funneling time and compressive strength in concrete to replacement ratio of LS. The results of this study is improved to flowing properties in fleshly concrete with increasing replacement ratio of LS. The optimal mixing condition of the SFC using LS in level of ordinary strength is proved W/C 55%, LS 40% and W/C 60%, LS 50%.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2007.11a
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• pp.41-44
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• 2007

Recently, the strenuous industrial waste is scattered and one of the oyster also make the serious environmental contamination. The purpose of this study is investigating an utilization ability as calcium binder of the oyster with Hwang-To according to a rate(10%, 20%, 30%, 40%, 50%). This study grasp physical properties of the oyster powder, bake production of the paste, and conduct the flow test, stiff time test and strength test. According to baking condition, strength of $1000^{\circ}C$(120minutes, rate 30%) is higher than any other condition. The oyster powder from above $900^{\circ}C$ seem possibility as binder hereafter. It is thought that the continuous research will be necessary.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2013.05a
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• pp.78-79
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• 2013

As a part of study to maximize the amount used of the ground granulated blast-furnace slag, the study deals with setting properties of paste that is mixed the ground granulated blast-furnace slag with CaO-Al₂O₃ based inorganic blinder. The results of the experiment show that the setting time is most fast in the mix of 25% rate of CaO-Al₂O₃ based inorganic blinder. It is generally needed 2 hours for work time in precast concrete products. In this study, this requirement is achieved when using the retarder of 0.5%.

• Transactions of Materials Processing
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• v.29 no.6
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• pp.307-315
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• 2020

The cemented carbide and stainless steel were bonded using a hot-vacuum brazing method to analyze the bonding interface. Since it is suitable for the hot vacuum brazing, nickel metal was used as a binder among the main components of the cemented carbide, and a new cemented carbide material was developed by adjusting the alloy composition. The paste, which is one of the important factors affecting the hot vacuum brazing bonding, was able to improve brazing adhesion by mixing solder as Ni powder and a binder as an organic compound at an appropriate ratio. Division of the stainless steel yielded a dense brazing result. This study elucidated the interfacial characteristics of wear-resistant parts by bonding stainless steel and cemented carbide via hot vacuum brazing.