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131.
Yuta IbusukiHajime Kunigo Yoshihiro Hirata Soichiro SameshimaNaoki Matsunaga 《Journal of the European Ceramic Society》2011,31(14):2663-2669
Fuel Cell performance was measured at 792-1095 K for Ni-GDC (Gd-doped ceria) anode-supported GDC film (60 μm thickness) with a (La0.8Sr0.2)(Co0.8Fe0.2)O3 cathode using H2 fuel containing 3 vol% H2O. A maximum power density, 436 mW/cm2, was obtained at 1095 K. The electrical conductivity of GDC electrolyte in N2 atmosphere of 10−15-100 Pa oxygen partial pressures (Po2) at 773-1073 K was independent of Po2, which indicated the diffusion of oxide ions. The conductivity of GDC in H2O/H2 atmosphere increased because of the further formation of electrons due to the dissociation of hydrogen in GDC (H2 → 2H+ + 2e−). The hole conductivity was observed at 873 K in Po2 = 100-104 Pa. The key factors in increasing power density are the increase of open circuit voltage and the suppression of H2 fuel dissolution in GDC electrolyte. These are controlled by the cathode material and Gd-dopant composition. 相似文献
132.
Sadahiro Tsurekawa Yuta Chihara Kyohei Tashima Seiichiro Ii Pavel Lejček 《Journal of Materials Science》2014,49(14):4698-4704
Nanoindentation was used to study incipient plastic deformation in the vicinity of grain boundaries of different character in Fe–3 mass% Si alloy bicrystals and tricrystal. Pop-in events associated with the grain boundaries were observed in the load–displacement curves. From the pop-in hardness values, the critical stresses required to propagate the yield past the grain boundary were estimated to be in the range of approximately µ/400–µ/130 (where µ is the shear modulus) depending on the grain boundary character: the special boundaries usually had higher critical stresses than the general boundaries. A Hall–Petch (H–P) type relationship was found between the hardness and the distance of the indenter to the grain boundary. The H–P slopes obtained were approximately one order of magnitude lower than the macroscopic value of the H–P slope for the Fe–3 mass% Si alloy, and were generally lower for general grain boundaries than for special boundaries. 相似文献
133.
Yuta Matsushima Tsutomu Yamazaki Kazuyuki Maeda Tatsuo Noma Takeyuki Suzuki 《Journal of the American Ceramic Society》2006,89(3):799-804
Plasma oxidation of a titanium electrode above liquid water was investigated to reveal the interaction between metallic titanium and plasma above liquid water. Dc-plasma was generated between the titanium and water electrodes. When the titanium electrode was set as anodal, a thick rutile layer was formed on the surface. We had reported previously that the layer showed the preferred orientation along 〈110〉normal to the surface. The degree of the preferred orientation showed a maximum of 0.8 at the electrode temperature of 1073 K. When the titanium electrode was set as cathodal, a plume was generated with the temperature rise because of the bombarding effect of cationic species in the plasma. The collected particles were spherical and were identified as anatase with a small amount of rutile. Optical emission spectroscopy suggested that an oxide layer (TiO2 ) firstly formed on the Ti cathode surface, and then vaporization took place with the temperature rise. The spherical anatase particles were formed from the TiO2 vapor through the rapid cooling. 相似文献
134.
Satoshi Murakawa Yuichiro Wada Yuta Tamura Masamichi Saitoh Yuki Aoki Ryuji Nomura Yuichi Okuda 《Journal of Low Temperature Physics》2008,150(3-4):154-159
We measured the complex transverse acoustic impedance of superfluid 3He in the B phase by coating a surface with 4He to study the boundary condition dependence of the surface bound states. Observed features in the temperature dependence
were similar to those without 4He coating. However, temperatures showing singularities became higher and variations in the dependence became smaller. The
small variations indicated that a specular surface was realized by the 4He coating. Increase in the singularity temperature indicated that the bandwidth of the surface Andreev bound states became
broader by the coating.
相似文献
135.
Ca3Co4O9 ceramic powders were synthesized by the polymerized complex (PC) method and consolidated by the hydrothermal hot-pressing
(HHP) technique. Observation by scanning electron microscope indicated that the form of powders by the PC process was fine
and flaky. The density of the sintered body increased with an increase of the operating temperature and pressure during the
HHP process. The electrical resistivity was greatly reduced with an increase of the operating pressure, but the thermal conductivity
is prone to increase with an increase of the operating temperature and pressure. The Seebeck coefficient was hardly affected
by the HHP condition. As a result, the sample treated by the HHP process under the condition of 573 K, 200 MPa, and 1 h showed
a maximum ZT of about 0.29 at 1,073 K. 相似文献
136.
137.
138.
Ishiuchi K Nakazawa T Ookuma T Sugimoto S Sato M Tsunematsu Y Ishikawa N Noguchi H Hotta K Moriya H Watanabe K 《Chembiochem : a European journal of chemical biology》2012,13(6):846-854
Fungal genome sequencing has revealed many genes coding for biosynthetic enzymes, including polyketide synthases and nonribosomal peptide synthetases. However, characterizing these enzymes and identifying the compounds they synthesize remains a challenge, whether the genes are expressed in their original hosts or in more tractable heterologous hosts, such as yeast. Here, we developed a streamlined method for isolating biosynthetic genes from fungal sources and producing bioactive molecules in an engineered Saccharomyces cerevisiae host strain. We used overlap extension PCR and yeast homologous recombination to clone desired fungal polyketide synthase or a nonribosomal peptide synthetase genes (5-20 kb) into a yeast expression vector quickly and efficiently. This approach was used successfully to clone five polyketide synthases and one nonribosomal peptide synthetase, from various fungal species. Subsequent detailed chemical characterizations of the resulting natural products identified six polyketide and two nonribosomal peptide products, one of which was a new compound. Our system should facilitate investigating uncharacterized fungal biosynthetic genes, identifying novel natural products, and rationally engineering biosynthetic pathways for the production of enzyme analogues possessing modified bioactivity. 相似文献
139.
The effect of alkali treatment on the isomerization of amino acids was investigated. The 100×D/(D+L) values of amino acids from peptide increased with increase in the number of constituent amino acid residues. Furthermore, the N-terminal amino acid of a dipeptide was isomerized to a greater extent than the C-terminal residue. 相似文献
140.