Al2O3 sol with long-term stability was prepared by mechanical milling. Thin films were evaluated and created for use as coating materials. The particle size of the manufactured sol was 98 nm when 2 wt% of nitric acid was added. This indicates that the viscosity of the sol is 12 cps and that it has long-term stability. The thickness of the thin films, which varied from 100 nm to 500 nm, could be managed by adjusting the draw rate and the amount of an organic additive. A thin film heated to 500˚C indicated a hydrophilic property against water and excellent permeability against a visible ray.
Effect The effect of sintering additives (SiO2, Al2O3, Clay) on the mechanical characteristics of sintered zircon was investigated. 1 vol% of additives in zircon powder was was sintered at 120~1500˚C, the mechanical characteristics were measured, and microstructure analysis were was conducted. Al2O3 and clay additions increase the formation of monoclinic and tetragonal-ZrO2 formation. An addition of SiO2 addition suppressed the formation of tetragonal-ZrO2 formation., The A specimen sintered at 1400˚C showed the a density of 4.05 g/cm3 and the a microhardness of 1120 HV, respectively.
Amorphous BaTi4O9 (BT4) film was deposited on Pt/Si substrate by RF magnetron sputter and their dielectric properties and electrical properties are investigated. A cross sectional SEM image and AFM image of the surface of the amorphous BT4 film deposited at room temperature showed the film was grown well on the substrate. The amorphous BT4 film had a large dielectric constant of 32, which is similar to that of the crystalline BT4 film. The leakage current density of the BT4 film was low and a Poole-Frenkel emission was suggested as the leakage current mechanism. A positive quadratic voltage coefficient of capacitance (VCC) was obtained for the BT4 film with a thickness of<70 nm and it could be due to the free carrier relaxation. However, a negative quadratic VCC was obtained for the films with a thickness ≥96nm, possibly due to the dipolar relaxation. The 55 nm-thick BT4 film had a high capacitance density of 5.1fF/μm2 with a low leakage current density of 11.6nA/cm2 at 2 V. Its quadratic and linear VCCs were 244ppm/V2 and -52 ppm/V, respectively, with a low temperature coefficient of capacitance of 961ppm/˚C at 100 kHz. These results confirmed the potential suitability of the amorphous BT4 film for use as a high performance metal-insulator-metal (MIM) capacitor.
비이온성 계면활성제로 많이 쓰이는 알킬페놀류의 하나인 노닐페놀(nonylphenol)이 해산어류에게 미치는 영향을 조사하려고 주요 양식어종인 조피볼락에게 복강주사로 10 및 25 mg kg-1을 1회 투여하였다. 한편 용제인 DMSO만을 주사한 sham구를 설정하여 비교하였다. 주사 후 7일간 간중량지수(hepatosomatic index)의 변화를 조사하였고, 또한 간장 미크로좀 중 대표적인 약물대사효소인 cytochrome P450 (CYP
연어류의 종간교배 실험과 LDH, MDH, IDH, GODH, ME 등 다섯가지 isozyme에 대한 genetic marker로서의 활용 가능성을 알아보고자 1차적으로 연어, 산천어 및 무지개송어를 이용하여 종간교배를 실시하였고 이들 세종의 isozyme pattern을 비교하였다. 교배실험은 종간교배, 및 allotriploid 구간 등 12구간으로 나누어 실시하였으며 연어 암컷과 산천어 수컷의 교배결과가 초기성장 단계적에서 가장 우수하게 나타났고이