• Proceedings of the Korea Concrete Institute Conference
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• 2009.05a
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• pp.399-400
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• 2009

This study arranged the result corrosion inhibition using Nano-silica for efficient prevention to diffusion of chloride ion. For the results, significant difference was not found on slump and air content, and there were superior effect to preventing diffusion of chloride ion on hardened concrete. It seemed to be Nano-silica prevented diffusion of chloride ion.

• Proceedings of the Korea Concrete Institute Conference
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• 2005.05b
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• pp.13-16
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• 2005

Nanoscale materials are of great interest due to their unique optical, electrical and magnetic properties. Due to the recent amazing achievements in nano technology, new materials were developed. But these nano technology is not apply to the construction part in spite of exellent properties of nano size material. The purpose of this study is to apply to nano technology into building materials. To develop the high performance concrete, nano cement particles is prepared by mechanical method. In the results of this study, the nano silica powder increase effect according to increase of the mixing amount, appeared that compressive strength increased but is limit in increment. For the production of high-strength concrete, nano silica powder was suitable the binder ratio from 20$\%$. And, the compressive strength of concrete are especially dependent on the curing temperature.

• Bulletin of the Korean Chemical Society
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• v.31 no.5
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• pp.1427-1429
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• 2010

• Bulletin of the Korean Chemical Society
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• v.29 no.11
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• pp.2281-2283
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• 2008

• The Plant Pathology Journal
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• v.22 no.3
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• pp.295-302
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• 2006

The present study addressed the efficacy of nanosized silica-silver for controlling plant pathogenic microorganisms. The nanosized silica-silver consisted of nano-silver combined with silica molecules and water soluble polymer, prepared by exposing a solution including silver salt, silicate and water soluble polymer to radioactive rays. The nanosized silica-silver showed antifungal activity against the tested phytopathogenic fungi at 3.0 ppm with varied degrees. In contrast, a number of beneficial bacteria or plant pathogenic bacteria were not significantly affected at 10 ppm level but completely inhibited by 100 ppm of nanosized silicasilver. Among the tested plant pathogenic fungi, the new product effectively controlled powdery mildews of pumpkin at 0.3 ppm in both field and greenhouse tests. The pathogens disappeared from the infected leaves 3 days after spray and the plants remained healthy thereafter. Our results suggested that the product developed in this study was effective in controlling various plant fungal diseases.

• Applied Chemistry for Engineering
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• v.19 no.1
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• pp.45-50
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• 2008

The self assembled silver process and silver coating process after surface reforming for silica particle, were investigated to coat the silver to colloidal silica. The effects of silver amounts and reductant amounts on silver coating efficiencies were investigated. The silver coating process after surface reforming for silica particle using MPTS (3-Mercaptopropyl trimethoxysilane) and APTS (3-Aminopropyl trimethoxysilane), showed the higher coating efficiency and better antibacterial effect than the self assembled silver process.

• Journal of Powder Materials
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• v.9 no.5
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• pp.365-369
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• 2002

Silica hydrogel was synthesized by the reaction of liquid sodium silicate with sulfuric acid. The condensation polymerization of the synthesized hydrogel was carried out via an aging process under the acidic or alkaline conditions. Nano porous silica with the pore size below 3 nm and surface area of $715m^2/g$, was obtained by the above processes in acidic ranges(pH : 3~5). The pore size and surface area of the silica varied with pH, and in alkaline ranges(pH : 8~10), those were 21 nm and $300m^2/g$ respectively. The characteristics of the silica varied with the thermal treatment which caused the change of surface area, pore volume and pore diameter.

• Korean Journal of Materials Research
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• v.15 no.12
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• pp.818-823
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• 2005

Sub-micron colloidal silica particles coated with nano-sized ceria were prepared by mixing of its silica and cerium salts hydrolysis, and modified by hydrothermal reaction. By using the slurries with and without hydrothermal modification containing above particles, oxide film coated on silicon wafer was polished. The modified slurries had higher polish rate due to increase of ceria fraction to silica through hydrothermal reaction. They revealed higher stability in wide range of pH $2\~10$ than ceria coated silica slurries without its modification.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.51 no.4
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• pp.561-566
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• 2015

In this study, the effect of temperature effect of the rubber matrix filled with nano sized silica particles composites with silica volume fraction of 19-25% was investigated by the Charpy impact test. The Charpy impact test was conducted in the temperature range from $-40^{\circ}C$ to $0^{\circ}C$. The critical energy release rate GIC of the rubber matrix composites filled with nano sized silica particles was considerably affected by temperature and it was shown that the maximum value was appeared at higher temperature between temperature tested and it was shown that the value of GIC increases as temperature tested increases. The major fracture mechanisms were matrix deformation, silica particle debonding and delamination, microcrack between particles and matrix, and/or pull out between particles and matrix which is ascertained by SEM photographs of Charpy impact surfaces fracture.

• Proceedings of the Materials Research Society of Korea Conference
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• 2006.11a
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• pp.15.2-15.2
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• 2006