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Silica capsules with hollow macroporous core–mesoporous shell (HCMS) were synthesized through template-assisted replication of submicrometer-size polystyrene spheres as templates. The silica mesoporous shell exhibited highly ordered hexagonal structure as confirmed by X-ray diffraction pattern and TEM image. The pore diameter and BET surface area of this sample were found to be 2.1 nm and 1387 m2/g, respectively.

The Korea Superconducting Tokamak Advanced Research (KSTAR) project is the major effort of the national fusion programme of the Republic of Korea. Its aim is to develop a steady state capable advanced superconducting tokamak to establish a scientific and technological basis for an attractive fusion reactor. The major parameters of the tokamak are: major radius 1.8 m, minor radius 0.5 m, toroidal field 3.5 T and plasma current 2 MA, with a strongly shaped plasma cross-section and double null divertor. The initial pulse length provided by the poloidal magnet system is 20 s, but the pulse length can be increased to 300 s through non-inductive current drive. The plasma heating and current drive system consists of neutral beams, ion cyclotron waves, lower hybrid waves and electron cyclotron waves for flexible profile control in advanced tokamak operating modes. A comprehensive set of diagnostics is planned for plasma control, performance evaluation and physics understanding. The project has completed its conceptual design and moved to the engineering design and construction phase. The target date for the first plasma is 2002.

Anomalous X-ray reflectivity measurements have been performed to extract electron density profile as a function of depth. Using a model independent analysis scheme based on distorted wave Born approximation, we have demonstrated that element-specific density profiles in a film can be obtained from reflectivity measurements done at two different X-ray energies, one at an absorption edge of the corresponding metal and another one away from it. The merit of this technique has been demonstrated with the results on high dielectric constant metal oxide Ta 2 O 5 films on Si(001). Our results show different Ta profiles near interfaces for Ta 2 O 5 /Si interface and Ta 2 O 5 /SiO 2 interface, implying different kinetics at these interfaces during annealing process.

A direct template carbonization using as-synthesized MCM-48 as template provides a simple and efficient synthetic method for highly ordered mesostructured carbons with great mechanical.

Publisher Summary This chapter discusses the novel synthesis of nanoporous carbons using colloidal templates. Ordered porous carbons are synthesized by the replication of colloidal templates made from 30–100 nm diameter silica spheres and removal of the silica templates using aqueous HF. To create the templates, the monodisperse particles are pressed into pellets and then sintered slightly at their points of contact. The silica template is filled with carbon precursor solution of divinylbenzene (DVB) and a free radical initiator, azobisisobutyronitrile (AIBN). Polymerization and carbonization of the precursor solution and subsequent dissolution of the silica templates leave a polycrystalline network of carbon with interconnected uniform pores. The degree of order of the silica template is reproduced in the carbon replicas.