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Phone: þ82 42 821 5451, Fax: þ82 42 822 8011 Iridate nanoparticle AIrO 3 (A ¼ Sr, Ba) incorporated Bi 2 Sr 2-CaCu 2 O 8 þ d (Bi-2212) thin films were successfully grown using pulsed laser deposition with post-growth ex situ heat treatment. Nanosized particles of SrIrO 3 (Sr-iridate) and BaIrO 3 (Ba-iridate) were deposited on top of MgO (100) substrate, followed by Bi-2212 layers to investigate their effects on the physical and superconducting properties of Bi-2212 thin films. The number of laser pulses was changed from 450 to 1800 to control the density of iridates in the Bi-2212 matrix. The composite film is then partial-melted at 890 8C for 15 min and annealed at 8508C for 5 h in ambient air. Scanning electron microscopy shows that the surfaces of thin films with iridates are more compact with minimal voids and porosity than those of pure Bi-2212 thin films. Both types of iridate incorporation suppress T c-zero of Bi-2212 thin films. Incorporating Sr-iridate in the Bi-2212 strongly affects T c-zero than those with Ba-iridate at low density. However, both iridate incorporations result in the expansion of the c-axis lattice constant and variation of Bi/Sr ratio of Bi-2212 films. On the other hand, we observed improvement of the activation energy, U 0 , as well as the selffield critical current density, J c (0), of Bi-2212 films with incorporated iridates even with suppressed T c-zero .

A fundamental understanding of film processing conditions and its effect on the microstructure, crystallinity, and electrical properties of thick layers of a GdBa2Cu3O7-δ (GdBaCuO) superconductor is necessary to optimize material requirements for its applications. In this work, the authors investigated the surface microstructure, crystalline quality, and superconducting properties of GdBaCuO thick films on (100) SrTiO3 single crystal substrates prepared by pulsed laser deposition (PLD). To clarify the effect of PLD growth conditions the substrate temperature, oxygen partial pressure, and laser fluence were systematically varied, then their impact was correlated on the microstructure and superconducting properties of thick layers of GdBaCuO films. By optimizing these growth conditions, the authors successfully obtained preferentially c-axis textured and superconducting films with a uniform and homogeneous layer up to 3.8 μm thick. Based on these results, the authors provide a key guiding principle in achieving thick highly c-axis textured superconducting GdBaCuO films using PLD.

Recently, technology for energy recovery from waste has been increasing interest globally including the Korea. In Korea, we have interested in using biogas generated from the sewage treatment process. As one alternative, there are operating biogas combined heat and power plant. The generation amount of the Sewage Sludge are expected to grow in the future. For this reason, total processing cost of Sewage Sludge will increase. To solve this problem, it seems will be invested with the expansion of facilities that use biogas as energy. Therefore, quantitative information on such facilities is required. Thus, this study attempts to economic feasibility analysis for Seonam Biogas Combined Heat and Power Plant. Meanwhile, as the benefit items for economic feasibility analysis consider electricity supply benefit except for heat supply benefit. The average prices of electricity use were residence 123.69, commercial 130.46, and industry 102.59 won per kWh for the year 2015, In addition, the economic benefit are calculated to be residence 310.21, commercial 378.49, and industry 222.87 won per kWh. The results of economic

The effects of composition and additives on the microstructures and magnetic properties of Nd-Fe-B melt-spun ribbons were studied. Experimental results have revealed that homogeneous grain structure with fine grain size was obtained on composition close to 2-14-1 stoichiometry with additives. It was also found that Nb was very effective in increasing both remanence and coercivity in a Nd-Fe-B melt-spun ribbon. A high-energy product of 151.2 kJ/m3 (19.0 MGOe) was obtained from an isotropic (Nd0.5Pr0.5)12Fe72Co8B6Nb2 melt-spun ribbon with a remanence of 0.926 T and a coercivity exceeding 1200 kA/m (∼15 kOe).