The plasma deposition apparatus developed in this study can realize a deposition of dense and high quality thin films, such as Si3N4 and SiO2, without the need for substrate heating. It does this by enhancing the plasma excitation efficiency at low gas pressures (10-4 Torr) and by the acceleration effect of ions with moderate energies (10 to 20 eV), using a microwave ECR (Electron Cyclotron Resonance) excited plasma, and a plasma stream extraction onto the specimen table by a divergent magnetic field method. The Si3N4 and SiO2 films deposited are comparable to those prepared by high temperature CVD and thermal oxidation, respectively, in evaluations such as by buffered HF solution etch rate measurement.

Plasma-facing materials and components in a fusion reactor are the interface between the plasma and the material part. The operational conditions in this environment are probably the most challenging parameters for any material: high power loads and large particle and neutron fluxes are simultaneously impinging at their surfaces. To realize fusion in a tokamak or stellarator reactor, given the proven geometries and technological solutions, requires an improvement of the thermo-mechanical capabilities of currently available materials. In its first part this article describes the requirements and needs for new, advanced materials for the plasma-facing components. Starting points are capabilities and limitations of tungsten-based alloys and structurally stabilized materials. Furthermore, material requirements from the fusion-specific loading scenarios of a divertor in a water-cooled configuration are described, defining directions for the material development. Finally, safety requirements for a fusion reactor with its specific accident scenarios and their potential environmental impact lead to the definition of inherently passive materials, avoiding release of radioactive material through intrinsic material properties. The second part of this article demonstrates current material development lines answering the fusion-specific requirements for high heat flux materials. New composite materials, in particular fiber-reinforced and laminated structures, as well as mechanically alloyed tungsten materials, allow the extension of the thermo-mechanical operation space towards regions of extreme steady-state and transient loads. Self-passivating

Four patients treated with the herbal medicine syo-saiko-to (xiao-chai-hu-tang) exhibited acute drug-induced liver injury. The latent period was one and a half to three months. All of the patients showed a rise in aminotransferases after readministration or challenge test. The liver histology revealed centrilobular confluent necrosis or spotty necrosis, microvesicular fatty change, acidophilic degeneration, and a granuloma. Cholestasis was seen in two patients. The results of the [13C]aminopyrine breath test, performed in one patient, were low before the challenge test and even lower after the challenge. These findings suggest that the herbal medicine syo-saiko-to may induce acute injury or the hepatocellular pattern with variable cholestasis.

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Mitigation of embrittlement caused by recrystallization and radiation is the key issue of tungsten (W) based materials for use in the advanced nuclear system such as fusion reactor applications. In this paper, our nanostructured W materials development performed so far to solve the key issue is reviewed, including new original data. Firstly, the basic concept of mitigation of the embrittlement is shown. The approach to the concept has yielded ultra-fine grained, recrystallized (UFGR) W(0.251.5) mass%TiC compacts containing fine TiC dispersoids (precipitates). The UFGR W(0.251.5)%TiC exhibits favorable as well as unfavorable features from the viewpoints of microstructures and various thermo-mechanical properties including the response to neutron and ion irradiations. Most of the unfavorable features stem from insufficient strengthening of weak random grain boundaries (GBs) in the recrystallized state. The focal point on this study is, therefore, to develop a new microstructural modification method to significantly strengthen the random GBs. The method is designated as GSMM (GB Sliding-based Microstructural Modification) and has lead to the birth of toughened, fine-grained W1.1%TiC in the recrystallized state (TFGR W1.1TiC). The TFGR W1.1TiC exhibits much improved thermo-mechanical properties. The applicability of TFGR W1.1TiC to the divertor in ITER is discussed.

The soft x-ray absorption and magnetic circular dichroism spectra at the Co L 2,3 -edges of [Co/Pd] 20 and [CoB/Pd] 20 multilayered films, which were sputter-deposited in Ar gas containing N 2 at room temperature, were measured to investigate the electronic and spin states of the films. The macroscopic magnetic properties, such as coercivity and saturation magnetization, and microstructural properties, such as grain size and preferred orientation, were markedly changed for the [Co/Pd] 20 film by the B doping and N 2 addition. The B doping and/or the addition of N 2 gas caused appreciable changes not only in macroscopic magnetic properties but also in microscopic properties, such as the spin angular momentum and orbital angular momentum, throughout the multilayered film. On the other hand, a new spectral feature at the high energy side of the Co L 3 -edge peak in x-ray absorption spectra was found in only the films with N 2 added. Thus, the microscopic properties, such as electronic and spin states, of the Co 3d electronic state for the [Co/Pd] 20 and [CoB/Pd] 20 films were changed by only the sputtering process with additive N 2 gas.

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