Epoxides are important raw materials in many chemical syntheses, as well as in industrial processes for the production of epoxy resins, paints, and surfactants. [1][2][3] Gas phase epoxidation of olefins by O 2 can be used for the production of ethylene oxide. [4] For higher molecular epoxides, however, the gasphase reaction is not feasible because of low selectivity, owing to competing oxidation at the allylic CÀH bonds. Higher molecular epoxides are commonly produced through liquid-phase epoxidation by H 2 O 2 , using transition metal homogeneous catalysts. Among the catalysts, tungsten-based catalysts have attracted significant attention in recent years, owing to their very high efficiency of H 2 O 2 utilization and selectivity to epoxides. [5][6][7][8][9][10][11][12] Despite their remarkable efficiency, they have drawbacks of separation from products and recyclability. Ion-exchange resins are widely used as supports for the immobilization of tungsten catalysts. [13][14][15][16][17] However, polymer resin based porous supports typically have a wide distribution of pore diameters, ranging from micropores (< 2 nm) to macropores (>50 nm). A large portion of the catalytic groups can be supported within micropores under these circumstances, leading to serious diffusion limitations. Another problem is that the loosely cross-linked polymeric frameworks can easily swell in many organic solvents. This swelling can lead to the closing of pore mouths under reaction conditions with organic solvents. In addition, water (H 2 O 2 carrier and by-product) can inhibit the access of hydrophobic organic reactants to the catalytically active sites through hydration of hydrophilic quaternary ammonium groups Ordered mesoporous silicas are often used as supports for tungstate catalysts to circumvent limitations related to diffusion. Mesoporous silicas have various advantages as catalyst supports. The silica mesopore diameters are uniform as compared to polymeric resins. The pore diameters can be precisely tailored over a mesoporous range, i.e., 2-50 nm. The mesopore walls are built with robust silica frameworks, which are covered by silanol groups. In the case of the polyoxotungstate catalysts, however, the surface silanol groups often render the mesoporous environment too hydrophilic to be used as a catalyst support in epoxidation using H 2 O 2 . The silanol groups can also interact strongly with catalytic groups, reactants and/or the products, thereby causing a loss of catalytic activity and/or selectivity.A number of synthesis routes to obtain ordered mesoporous polymeric materials (MPMs) have been developed in recent years. The MPMs obtained in this manner have uniform mesopores built with hydrophobic organic frameworks. The pore diameters can be tailored and the organic frameworks can be functionalized through co-polymerization and/or post-synthesis organic reactions. [18][19][20][21][22] In particular, Choi and Ryoo demonstrated that a fully cross-linked and rigid poly(divinylbenzene) MPM could be synthesized using a polymeriza...

We extended the density-gradient (DG) model to include a second-order quantum correction (SOQC) term. The DG model has been widely used as a device simulation model capable of simulating quantum effects in efficient way. However, when only the first order quantum correction term is considered in the DG model, it is difficult to accurately describe device characteristics such as carrier density or potential fluctuation in the narrow region due to discrete charges such as dopants and interface traps. Thus, we extended the DG model to the SOQC, implemented it as a three-dimensional (3D) simulator, and compared the simulation results for sub-10-nm devices, which have a single point charge, in the DG model and the 3D Schrödinger-Poisson (SP) solver. Through this, we identified that the DG extended to SOQC well reproduces the SP simulation results in terms of both capacitance-voltage (C-V) and local fluctuation in electron density.