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The KN18 is a new cask design by KONES for KHNP for the dry or wet transportation of up to 18 PWR spent nuclear fuel assemblies in South Korea. The containment vessel consists of a cylindrical thick-walled forged steel body, closed by a stainless steel lid with bolts. Spent fuel assemblies are located in a basket which consists of a tube disc system. Two pairs of trunnions are attached for lifting, manoeuvring and tie-down. A pair of impact limiters manufactured from wood and encased in steel cladding provide impact energy absorption during the hypothetical accident conditions. The package complies with the requirements of 10 CFR Part 71 for Type B(U)F packages. It received its transport license from the Korean Competent Authority KINS in early 2010 and is expect to enter service in 2011. Structural performance of the package in the normal and accident conditions were demonstrated against the requirements of 10 CFR Part 71 by analysis including extensive calculations by state-of-the-art finite ele...

Single-phase BiFeO3 powder was successively synthesized by a low-temperature hydrothermal method. Scanning electron microscopy and transmission electron microscopy results showed that BiFeO3 powder had several hundred nanometers to micrometer-sized particles with a broad size distribution. BiFeO3 powder showed weak-ferromagnetic behavior with a small magnetization value (Ms approximately 20 memu/g) at room temperature. Rietveld refinement results for the crystal structure show the displacive disorder of the Fe-site(6a); the Fe-site(6a) splits into two pairs, Fe(1) and Fe(2) displaced by 0.9 angstroms from each other and these sites are partially occupied. Hence the O-site(18b) also splits into the two partially occupied sites forming a distorted FeO6 octahedras. The weak ferromagnetism observed in the hydrothermal BFO powder is ascribed to the displacive disorder of FeO6 octahedras resulting in an incomplete counterbalance between the antiferromagnetic sublattices of the Fe-ions.

The influence of processing parameters on phase formation and particle size of hydrothermally synthesized BiFeO3 powders was investigated. BiFeO3 powder was synthesized by dissolving bismuth nitrate and iron nitrate in KOH solution at temperatures ranging from 150 to 225 °C. X-ray diffraction patterns and scanning electron microscopy observation indicated that rod-like α-Bi2O3 phase was formed at initial stage of reaction and dissolved into ions to form thermodynamically stable BiFeO3 phase. Single-phase perovskite BiFeO3 has been formed using a KOH concentration of 8 M at a temperature of ≥175 °C in a 6 h reaction period. BiFeO3 particle growth was promoted by lowering the KOH concentration, or increasing the duration time or reaction temperature. The effects of processing conditions on the formation of crystalline BiFeO3 powders were discussed in terms of a dissolution–precipitation mechanism. The magnetization of the BiFeO3 powders at room temperature showed a weak a ferromagnetic nature.