l-Proline was immobilized onto mesoporous silica through direct synthesis method via morphosynthesis possessing short channels and plugs in the pore structure which provided chiral enhancement in the diethyl malonate addition reaction.

Mesoporous silica having L-proline functionality and plugged pore structure was synthesized by direct microwave synthesis under acidic condition using Pluronic P123 as template and sodium metasilicate nonahydrate as silica source. The direct synthesis resulted in the prismatic or disk types with short channels and plugs in the pore structure. Due to the presence of plugs, dual mesoporosities with 7 and 3 nm pore diameter were generated leading to an existence of cavitation. Tri-functionality of this materials i.e. chiral organofunctional group, plugs, and short channel, would be useful for the asymmetric diethyl malonate addition reaction and asymmetric epoxidation reaction of a,b-unsaturated aldehydes. We proved that the formation of plugs in the mesoporous silica governs the formation of dual mesoporosities providing an enhancement of enantiomeric excess in the asymmetric catalysis.This finding might open an important application of the amino-acid organo multifunctionalized mesoporous silica for asymmetric reactions.

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This study was designed to evaluate mechanical properties and the marginal fitness of glass infiltrated alumina core fabricated from aqueous alumina tape. Utilizing the automatic Dr. Blade model (DP-150 of Japan JinChungjungGi manufacturer) fabricated the slurry into 0.5 ㎜ thickness aqueous-based alumina tape. The coefficient of thermal expansion and biaxial flexural strength of alumina composite produced from alumina tape were investigated. Three upper central resin incisors were prepared with 90o, 110o, 135o shoulder margin for all-ceramic crown. Individual tooth model’s impressions were taken 15times each to make epoxy resin die. Cores were made of alumina tape to each and every dies. Crown setting was done on the epoxy resin dies. The specimens were evaluated for measuring for marginal gaps of glass infiltrated alumina core fabricated from aqueous alumina tapes under 180 magnifications with Kan Scope(Sometech Vision, Korea) was done. The retained measurements were analyzed with Turkey’s Studentized Range Test for marginal fitness of each specimen. Coefficient of thermal expansion of alumina tape was 7.5x10-6/°C, and biaxial flexural strength was observed to be 498±32MPa. The marginal fits of alumina cores made of alumina tapes showed the least marginal gap of 41.5 ㎛ in the 110o shoulder margin, and increasingly with 135o, 90o shoulder margin. Marginal fitness should be better in angles larger than 90o.