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A survey to investigate the inhabitation of Callipogon relictus Semenov and evaluate the population of the species in the Gwangneung Forest was conducted during last seven years. During the study, a female was observed in the forest in 2006 which confirmed a possibility of the inhabitation with a small population. Fortunately, a ovipositing female was observed in the forest during this study period in 2006. The female laid more than 20 eggs singly in the crack of bark of the Carpinus laxiflora Blume. We collated the all available data for the species with the present study including the previous reports to provide the information far the conservation plan. It will be needed the long term monitoring and various efforts for the conservation of the species will be need hereafter.

In this study, we investigated the effect of the average grain size on the transmittance and mechanical strength of high purity sintered alumina. When the grain size was reduced from 2 to 0.8 μm, the transmittance abruptly increased due to Rayleigh scattering. However, sintered alumina with a grain size of between 2 and 7 μm showed no transmittance. The transmittance slightly increased when the grain size was increased to more than 7 μm. The bending strength of the sintered alumina increased with decreasing grain size, which was well matched with the theoretical considerations. Polycrystalline alumina with an average grain size of 0.8 μm exhibited high transmittance and high mechanical strength.

For the development of a new wear resistant and chemically stable glass-ceramic glaze, the CaO–ZrO 2 –SiO 2 system was studied. Compositions consisting of CaO, ZrO 2 , and SiO 2 were used for frit, which formed a glass-ceramic under a single stage heat treatment in electric furnace. In the sintered glass-ceramic, wollastonite (CaSiO 3 ) and calcium zirconium silicate (Ca 2 ZrSi 4 O 12 ) were crystalline phases composed of surface and internal crystals in the microstructure. The internal crystal formed with nuclei having a composition of Ca 1.2 Si 4.3 Zr 0.2 O 8 . The CaO–ZrO 2 –SiO 2 system showed good properties in wear and chemical resistance because the Ca 2 ZrSi 4 O 12 crystals positively affected physical and mechanical properties.

AgInS2 epilayers have been grown on a GaAs substrate by using the hot-wall epitaxy method. The temperature dependence of the band gap energy of AgInS2 is determined to be E g (T)=2.1365 eV −(9.89×10 −3 eV )T 2 /(2930+T) using the absorption spectra. The free exciton binding energy, Δcr, and Δso of the chalcopyrite AgInS2 have been found to be 0.1115, 0.1541, and 0.0129 eV, respectively. This result reveals that the Δso splitting clearly exists for the Γ5 states of the valence band in the AgInS2 epilayer.

The ZnSe/GaAs epilayers grown by hot wall epitaxy have been investigated by means of Raman, and photocurrent (PC), and photoluminescence spectroscopy. Raman spectroscopy measurement showed that a plasmon-longitudinal optical phonon-coupling mode existed together with its characteristic longitudinal optical phonon. The temperature dependence of the energy band gap of the ZnSe/GaAs epilayer was found to be E g (T)=2.8210 eV −(9.11×10 −4 eV/K )T 2 /(298.1+T) based on PC measurement. Also, the energy band gap, Eg(T), at 300 K has been determined to be 2.6839 eV. From the photoluminescence spectra, two dominant peaks of 2.7988 and 2.7937 eV separated from the free exciton peak at 442.4 nm (2.8026 eV) have been found to be associated with the upper and the lower polariton peak of the exciton, I2 (Do, X), respectively. This polariton peak is attributed to the strain due to the lattice mismatch between the substrate and the ZnSe epilayer. On the basis of the obtained results, the donor-impurity binding energy is calculated to be 25.3 meV.

Abnormal grain growth (AGG) occurs when SnO 2 thin films are deposited by conventional thermal CVD at 475 °C, and high-resolution transmission electron microscopy shows some of the interfaces to be atomically faceted. However, when deposited at 525 °C normal grain growth (NGG) occurs with all the interfaces smoothly curved and atomically rough. This correlation between interface structure and grain growth behavior is consistent with that observed previously in bulk materials. For the application of SnO 2 thin films in sensors and transparent electrodes, 525 °C, which is just above the faceting transition temperature, was found to be the optimum deposition temperature due to its small grain size and high surface to volume ratio.