• Journal of Welding and Joining
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• v.24 no.2
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• pp.57-63
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• 2006

In this study, the curing kinetics and thermal degradation of underfill were investigated using differential scanning calorimetry (DSC) and thermo gravimetry analysis (TGA). The mechanical and thermal properties of underfill were characterized using dynamic mechanical analysis (DMA) and thermo-mechanical analysis (TMA). Also, we presented on underfill dispensing process using Prostar tool. The non-isothermal DSC scans at various heating rates, the exothermic reaction peak became narrower with increasing the heating rate. The thermal degradation of underfill was composed of two processes, which involved chemical reactions between the degrading polymer and oxygen from the air atmosphere. The results of fluidity phenomena were simulated using Star CD program, the fluidity of the underfills with lower viscosity was faster.

• Proceedings of the Korea Concrete Institute Conference
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• 2000.10a
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• pp.661-664
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• 2000

It is known that high flowing concrete performs much higher fluidity, segregation resistibility and better placeability than normal concrete. However, it is hard to apply high fluidity concrete in field because of high manufacturing cost. Therefore, we intend to investigate the validity of segregation reducing type superplasticizer which is made by combining 0.61 of viscosity agent and 0.022 of AE agent for 1 of superplasticizer. Test are conducted on high flowing concrete using fly ash by applying segregation reducing type superplasticizer. According to experimental results, As contents of fly ash increase, fluidity, segregation resistibility and placeability shows favorable results. And also compressive strength at early age shows to be retarded, while it gains high strength at later age.

• Proceedings of the Korea Concrete Institute Conference
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• 1997.10a
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• pp.241-246
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• 1997

This paper tried to catch the fluidity and rheology nature of paste, using the W/P, flay-ash and additional amount of superplasticizing agent as experimental factor. Form result of experiment, as the amount of superplasticizing agent increased, fluidity increased and the rheology decreased. As the substitutional ratio increased fluidity decreased, the rheology tended to increase, additional amount of agent to gain high flowing range is different according to w/p, but this experiment shows about 0.5~1.0% in fly-ash 10~30% substitutional range, 1.0~1.5% in fly-ash 50%.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2017.05a
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• pp.208-209
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• 2017

This study analyzed the fluidity and strength properties of mortar containing high volume blast furnace slag by replacement ratio of lightweight fine aggregate for reducing the unit weight of concrete structures.

• Proceedings of the Korea Concrete Institute Conference
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• 1996.10a
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• pp.154-165
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• 1996

As II-anhydrite reacts with C3A(aluminate), C4AF(ferrite) at initial hydration of cement and assists the hydrolysis of C3S(calcium silicate), the production rate of ettringite(3C3A.3CaSO4.32H2O) and C-S-H gel was acclerated. It was known that compressive strength of cement concrete improved due to the effect of II-anhydrite. For the checking these effects of II-anhydrite, the fluidity and compressive strength of cementmortar admixed with II-anhydrite and pozollanic fine powders were investigated. By means of SEM analysis, the surface structure of mortar with the condition of steam curing at curing days=28 was investigated. As a result of this experiment, it was examined that II-anhydrite had an increase on the fluidity of cementpaste and compressive strength of mortar.

• Proceedings of the Korea Concrete Institute Conference
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• 2006.11a
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• pp.925-928
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• 2006

The effects of polymer-binder ratio, antifoamer content and shrinkage-reducing agent content on the air content and strengths of high-fluidity polymer-modified pastes are examined. As a result, the air content of the polymer-modified pastes tends to decrease with increasing polymer-binder ratio and antifoamer content. Irrespective of the antifoamer content, the flexural and tensile strengths of the high-fluidity polymer-modified pastes tends to increase with increasing polymer-binder ratio, and tend to decrease with increasing shrinkage-reducing agent content. However, the compressive strength of the polymer-modified pastes decreases with increasing polymer-binder ratio and shrinkage-reducing agent content.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2020.11a
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• pp.81-82
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• 2020

Cement paste is the basic material constituting concrete and the most basic data of workability. This study quantitatively evaluated the measured data using a ring flow and a rotary viscometer to estimate the flow of cement paste, and also evaluated the flow and rheology over time. For this, the current work has studied admixtures that affect the fluidity of cement paste. As a result of the experiment, since fluidity and plastic viscosity are inversely proportional to each other, more experimental studies are needed to obtain high fluidity and high viscosity at the same time.

• Journal of the Korean Graphic Arts Communication Society
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• v.21 no.2
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• pp.75-87
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• 2003

Printing inks are mainly composed of pigment and vehicles. Among these components, the Vehicle affect the rheologic property of the ink the most but pigment content of characteristic also after to the fluidity property not less than the vehicle. In the study, It is tested effect to the ink fluidity and structure recovery according to change the pigment particle size. The ink fluidity have been observed by using rheometer at the various conditions and it has been tested to observe what the ink fluidity has different means. In result We have found that the viscosity value of the low shear rate range has relatively higher value with decreasing the pigment particle size in the ink. Also, it has been found that when the pigment particle size decreases, the yield stress gradually increase. In the case of ink's structure recovery, when the pigment particle size decreases in the ink, the less changing shear rate, and it takes less time to recover.

• Journal of the Microelectronics and Packaging Society
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• v.6 no.4
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• pp.41-48
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• 1999

Silica is the most popular materials as a filler of EMC for microelectronic packaging. However, because of its low thermal conductivity, the use of silica is restricted to parts requiring high thermal dissipation. The superior fluidity of EMC can be achieved with a combination of filler size distribution. In this study, physical properties of EMC filled with the crystalline silica(13$\mu\textrm{m}$) which have high fluidity and low cost and the AlN(2 $\mu\textrm{m}$) which have high thermal conductivity and low coefficient of thermal expansion were evaluated by changing the AlN/silica ratios. As a result of the evaluation of physical properties of EMC, the optimum mixing ratio of AlN/crystalline silica was 0.3/0.7. In this condition, binary mixture(AlN/crystalline silica) filled EMC showed superior properties, i.e., in the thermal conductivity, CTE, dielectric constant, flexural strength, and thermal shock resistance without reduction of fluidity.

• Journal of Photoscience
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• v.12 no.2
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• pp.67-73
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• 2005

Fluorescent probe techniques were used to evaluate the effect of dibucaine.HCl on the physical properties (transbilayer asymmetric lateral mobility, annular lipid fluidity and protein distribution) of synaptosomal plasma membrane vesicles (SPMV) isolated from bovine cerebral cortex. An experimental procedure was used based on selective quenching of 1,3-di(l-pyrenyl)propane (Py-3-Py) by trinitrophenyl groups, and radiationless energy transfer from the tryptophans of membrane proteins to Py-3-Py. Dibucaine.HCl increased the bulk lateral mobility, and annular lipid fluidity in SPMV lipid bilayers, and had a greater fluidizing effect on the inner monolayer than the outer monolayer. The magnitude of increasing effect on annular lipid fluidity in SPMV lipid bilayer induced by dibucaine.HCl was significantly far greater than magnitude of increasing effect of the drug on the lateral mobility of bulk SPMV lipid bilayer. It also caused membrane proteins to cluster. These effects of dibucaine.HCl on neuronal membranes may be responsible for some, though not all, of the local anesthetic actions of dibucaine.HCl.