• Proceedings of the Korean Institute of Building Construction Conference
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• 2004.05a
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• pp.33-37
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• 2004

Recently, Growing tendency for structure surface to use water repellent agent has increased steadily. But investigation of it's protection and durability property is not sufficient. Therefore, this paper shows the investigation about repellent property and micro structure's change in surface layer of mortar that is applied by water repellent agent. Water repellent property, absorption coefficient, air permeability, porosity and observation of micro construct was investigated according to water repellent agent type. The test results indicated that mortar applied water repellent agent appears tiny absorption coefficient, but air permeability is maintained. The reason is because silane solution is coating at capillary surface of a wall and minute pore structure is changeless.

• Proceedings of the SCSK Conference
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• 2003.09a
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• pp.568-569
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• 2003

Functional cosmetic ingredients such as L-ascorbic acid, retinoic acid, indole-3-acetic acid, salicylic acid, acidic dye(indigo carmine) are intercalatively encapsulated by skin-friendly metal hydroxides and oxides matrices. Such functional organic-inorganic nanohybrids are realized via chemical coprecipitation and surface coating reactions. The hetero-structural nature of these nanohybrids, their particle morphology and textural characterizations are mainly discussed on the basis of powder X-ray diffraction, electron microscopies, and high performance liquid chromatographic analyses. The cosmetic ingredients encapsulated in inorganics show greatly improved storage stability, sustained releasing property as well as higher transdermal transfer efficiency.

• Proceedings of the Membrane Society of Korea Conference
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• 1996.10a
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• pp.55-57
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• 1996

다공성 무기막은 높은투과도와 뛰어난 내열.내화학성, 그리고 경제성 때문에 기존의 PSA공정이나 증류와 같은 고에너지 분리공정을 대체하는 공정으로 각광을 받고 있다. 무기재료막의 제조하는 방법으로 주로 알콕사이드를 사용하는 솔-젤법(1)과 금속(2) 또는 기상반응(3)을 이용하는 화학증착법이 사용된다. 또한 고온에서 수소를 연속적으로 분리하여 화학평형에 기인한 한계를 극복하여 높은 수율을 얻고자하는 막반응기에 관한 연구가 활발히 진행되고 있다. 본 연구에서는 $\alpha$-알루미나 지지체의 미세한 다공성 구조 내부에서 TEOS(Tetraethylorthosilicate)와 산성의 알코올-물 혼합물을 확산시켜 실리카 솔을 생성시킴과 동시에 젤화시켜 기공의 크기를 감소시켜 막을 제조하였다. 이렇게 제조된 막은 높은 투과도와 낮은 수소선택도(selectivity=3-4)를 보였고, 두번째 단계로 silica sol을 제조하여 진공 하에서 dip-coating을 행하였다. 이렇게 2단계로 기공 구조를 개선시킨 실리카 막은 저압에서 상대적으로 높은 수소의 분리도(selectivity=5-7)를 보였으며 여전히 높은 투과도를 갖는다.

• Proceedings of the Membrane Society of Korea Conference
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• 2002.05a
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• pp.35-41
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• 2002

Dense oxygen ionic conducting materials can be used for oxygen separation membranes at high temperatures. However, they show relatively low permeation flux because of their large resistances. To reduce resistances and improve the oxygen permeation flux, thin dense yttria-stabilized-zirconia (YSZ)/Pd composite dual-phase membranes were fabricated by a new approach that combines the reservoir method and chemical vapor deposition (CVD). A thin porous YSZ layer was coated on a porous alumina support by dip-coating the YSZ suspension. A continuous Pd phase was formed inside pores of the YSZ layer by the reservoir method. The residual pores of the YSZ/Pd layer were plugged with yttria/zirconia by CVD to ensure the gas tightness of the membranes. The oxygen permeation fluxes through these composite membrane were 2.0$\times$10$^{-8}$ mol/cm$^2$.s and 4.8$\times$10$^{-8}$ mol/cm$^2$.s at 105$0^{\circ}C$ when air and oxygen were used as the permeate gases, respectively. These oxygen permeation values are about 1 order of magnitude higher than those of pure YSZ membranes prepared under similar conditions.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.18 no.12
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• pp.1106-1110
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• 2005

We fabricated (110) silicon hard master by using anisotropic wet etching for embossing. The etching chemical for the silicon wafer was a TMAH $25\%$ solution. The anisotropic wet etching produces a smooth sidewall surface and the surface roughness of the fabricated master is about 3 nm. After spin coating an organic-inorganic sol-gel hybrid material on a silicon substrate, we employed hot embossing technique operated at a low pressure and temperature to form patterns on the silicon substrate by using the fabricated master. We successfully fabricated the multi-mode planar optical waveguides showing low propagation loss of 0.4 dB/cm. The surface roughness of embossed patterns was uniform for more than 10 times of the embossing processes with a single hydrophobic surface treatment of the silicon hard master.

• Journal of the Korean Ceramic Society
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• v.42 no.10 s.281
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• pp.645-648
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• 2005

To fabricate a (100) silicon hard master, we used anisotropic wet etching for the embossing. The etching chemical for the sili­con wafer was a TMAH 25$\%$ solution. The anisotropic wet etching produces a smooth sidewall surface inclined at 54.7°, and the surface roughness of the fabricated master is about 1 nm. After spin coating an organic-inorganic sol-gel hybrid resin on a silicon substrate, we used the fabricated master to form patterns on the silicon substrate. Thus, we successfully obtained patterns via the hot embossing technique with the (100) silicon hard master. Moreover, by using a single hydrophobic surface treatment of the master, we succeeded in achieving uniform surface roughness of the embossed patterns for more than ten embossments.

• Proceedings of the Korean Vacuum Society Conference
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• 2014.02a
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• pp.365.2-365.2
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• 2014

Nickel sulfide (NiS) has been utilized in optoelectronic applications, such as transformation-toughening agent for materials used in semiconductor applications, catalysts, and cathodic materials in rechargeable lithium batteries. Recently, high quality nickel sulfide thin films have been explored using ALD/CVD technique. Suitable precursors are needed to deposit thin films of inorganic materials. However, nickel sulfide precursors available for ALD/CVD process are very limited to nickel complexes with dithiocarbamate and alkanethiolate ligands. Therefore, it is essential to prepare novel nickel sulfide suitable for ALD/CVD precesses. Herein we report on the synthesis and characterization of new nickel sulfide complex with designed aminothiolate ligand. Furthermore thin films of NiS have been prepared on silicon oxide substrates by spin coating nickel precursor 10 wt% in THF. The novel complex has been characterized by means of 1H-NMR, elemental analysis, thermogravimetric analysis (TGA), X-ray Diffraction (XRD) and scanning electron microscope (SEM).

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 1993.10a
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• pp.97-102
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• 1993

The application of epxy composite materials for the outdoor insulating systems has some significant advan-tages compared with conventional inorganic materials, that is low weight in combination with high mechanical strength, small dimensions and design versatility. The paper describes the results of high voltage investigations carried out different aging types of epoxy resin insulator and silicone grease coating. The insulators have been exposed 3000 hours to weather-o-meter and 12 months to outdoor. In this connection, the main study of paper is form the basis of develop-ment of principal technologies of epoxy composites which ard: (1)manufacturing of insulator, (2)high vol-tage testing under dry and wet condition, (3)mechani-cal properties, (4)accelerated weather-ometer test and outdoor exposed, artificial polution.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2012.11a
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• pp.66-67
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• 2012

As polymer coatings of nano-structured surface become significant to obtain functionalized materials, catechol derived from a mussel protein has attracted increasing attention for its universal adhesiveness. In addition to the unique adhesion property, its reducing ability of metal ions during oxidative polymerization to polydopamine (pD) widely expands the application of catechol molecules in the field of surface modification. In this study, we present the catechol conjugated smart polymer coatings for regulating surface properties such as wettability and anti-fouling effects. In additino, the in situ silver coating of electrospun polymer nanofibers using a silver-catechol redox reaction is presented as a simple method to produce metal nanostructures.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2006.05a
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• pp.43-46
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• 2006

In this study on the appliable Asphalt sheet of monolithic and inorganic matter waterproofing material using of field because of problem of complex waterproofing sheet. Before this cement polymer modified waterproof coating and appliable asphalt sheet of monolithic whether have stability by method of construction about all style waterproofing that evaluate to new method of construction development naturally big emphasis put and try to approach. Did performance test item first at, as a result, drew by suitable thing in all KS items. This is considered to have more effective spot construction work because if means that have stability by material as well as method of construction.