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111.
112.
Chinatsu Okamura Takashi Ueda Kazuhiro Hasezaki 《Journal of Electronic Materials》2010,39(9):2172-2175
Single-phase β-Zn4Sb3 materials were prepared by mechanical grinding (MG). Source materials for the Zn4Sb3 ingots were prepared using three different processes after the direct melting of constituent elements. In process 1, the
ingot was obtained by quenching the melt in water within an evacuated quartz ampoule. In process 2, the ingot was heat-treated
for 100 h at 723 K after process 1. In process 3, the ingot was heat-treated for a total of 200 h in two stages at 723 K and
673 K after process 1. The resultant ingots were mechanically ground and sintered at 623 K by hot pressing. The sintered materials
were characterized by x-ray diffraction, differential thermal analysis (DTA), and thermoelectric property measurements. The
thermal conductivity of the sintered materials was 0.88 W m−1 K−1 at room temperature, being slightly lower than that reported for the materials prepared by a conventional method. Results
indicate that the dimensionless figure of merit of the single-phase β-Zn4Sb3 ranged from 1.06 to 1.31 at 573 K. 相似文献
113.
V. Matolín M. Cabala I. Matolínov M. koda M. Vclav K.C. Prince T. Skla T. Mori H. Yoshikawa Y. Yamashita S. Ueda K. Kobayashi 《Fuel Cells》2010,10(1):139-144
The interaction of Pt with CeO2 layers was investigated by using photoelectron spectroscopy. Thirty‐nanometre‐thick Pt and Sn doped CeO2 layers were deposited simultaneously by rf‐magnetron sputtering on a Si(001) substrate and a carbon diffusion layer of a polymer membrane fuel cell by using a composite CeO2–Pt–Sn target. The laboratory XPS and synchrotron radiation soft X‐ray and hard X‐ray photoemission spectra showed the formation of cerium oxide with completely ionised Pt2+,4+ species, and with Pt4+ embedded in the film bulk. Hydrogen/air fuel cell activity measurements normalised to the amount of Pt used revealed high specific power of up to 5.4 × 104 mW mg–1 (Pt). The activity of these materials is explained by the strong activity of embedded Ptn+ cations. 相似文献
114.
Antioxidant Effects of Herbal Tea Leaves from Yacon (Smallanthus sonchifolius) on Multiple Free Radical and Reducing Power Assays,Especially on Different Superoxide Anion Radical Generation Systems 下载免费PDF全文
Shintaro Sugahara Yuto Ueda Kumiko Fukuhara Yuki Kamamuta Yasushi Matsuda Tatsuro Murata Yasuhiro Kuroda Kiyotaka Kabata Masateru Ono Keiji Igoshi Shin Yasuda 《Journal of food science》2015,80(11):C2420-C2429
Yacon (Smallanthus sonchifolius), a native Andean plant, has been cultivated as a crop and locally used as a traditional folk medicine for the people suffering from diabetes and digestive/renal disorders. However, the medicinal properties of this plant and its processed foods have not been completely established. This study investigates the potent antioxidative effects of herbal tea leaves from yacon in different free radical models and a ferric reducing model. A hot‐water extract exhibited the highest yield of total polyphenol and scavenging effect on 1,1‐diphenyl‐2‐picryl hydrazyl (DPPH) radical among four extracts prepared with hot water, methanol, ethanol, and ethylacetate. In addition, a higher reducing power of the hot‐water extract was similarly demonstrated among these extracts. Varying concentrations of the hot‐water extract resulted in different scavenging activities in four synthetic free radical models: DPPH radical (EC50 28.1 μg/mL), 2,2′‐azinobis(3‐ethylbenzothiazoline‐6‐sulfonic acid) cation radical (EC50 23.7 μg/mL), galvinoxyl radical (EC50 3.06 μg/mL), and chlorpromazine cation radical (EC50 475 μg/mL). The yacon tea‐leaf extract further demonstrated superoxide anion (O2?) radical scavenging effects in the phenazine methosulfate‐NADH‐nitroblue tetrazolium (EC50 64.5 μg/mL) and xanthine oxidase assay systems (EC50 20.7 μg/mL). Subsequently, incubating human neutrophilic cells in the presence of the tea‐leaf extract could suppress the cellular O2? radical generation (IC50 65.7 μg/mL) in a phorbol 12‐myristate 13‐acetate‐activated cell model. These results support yacon tea leaves may be a good source of natural antioxidants for preventing O2? radical‐mediated disorders. 相似文献
115.
Higuchi M Miyata D Kawamura S Ueda E Imanaka M Tonogai Y 《Shokuhin eiseigaku zasshi. Journal of the Food Hygienic Society of Japan》2004,45(6):339-343
Daily intakes of 12 phenols which are possible endocrine disruptors were estimated in hospital meals from 2000 to 2001. 4-Nonylphenol (4-NP (mix)) and bisphenol A (BPA) were detected at levels of 5.0 to 19.4 ng/g and 0.2 to 1.1 ng/g, respectively. 4-tert-Butylphenol, 4-n-pentylphenol, 4 -tert-pentylphenol, 4-n-hexylphenol, 4-n-heptylphenol and 4-tert-octylphenol were detected at levels of 0.1 to 2.4 microg/g. The daily intakes of 4-NP (mix) and BPA were 5.8 microg/day and 0.42 microg/day, respectively. The daily intakes of other phenols were less than 1 microg/day. 相似文献
116.
Acrolein formation in the oxidation of ethane over silica catalysts supporting iron and cesium 总被引:1,自引:0,他引:1
Kiyoharu Nakagawa Yonghong Teng Zhen Zhao Yusuke Yamada Atsushi Ueda Toshimitsu Suzuki Tetsuhiko Kobayashi 《Catalysis Letters》1999,63(1-2):79-82
A significant yield of aldehydes was obtained by the partial oxidation of ethane over alkali‐modified Fe/SiO2 catalysts at 475°C (<2% in the case of Cs–Fe/SiO2). Not only acetaldehyde and formaldehyde but also acrolein were produced in the present system. There are no reports regarding
the catalysts for the direct acrolein formation from partial oxidation of ethane. Such significant promoting effect of alkali‐modified
Fe/SiO2 catalysts in the partial oxidation of hydrocarbons has never been observed. Aldol‐type condensation for formation of acrolein
could occur in the partial oxidation of ethane over alkali‐modified Fe/SiO2 catalysts.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
117.
Toshihiro Hiejima Yosuke Takamizawa Yoshinori Tanaka Kenji Ueda Takayuki Uchida 《Synthetic Metals》2009,159(9-10):986-989
The characteristics of EL devices containing α-helical poly(l-glutamate) and having a carbazole side chain (PCELG) were found to strongly depend on the casting solvents. Among EL devices fabricated using chlorine-containing casting solvents such as 1,2-dichloroethane (DCE), 1,1,2,2-tetrachloroethane (TCE), chloroform (CHCl3), and monochlorobenzene (?-Cl), the EL device fabricated using the DCE solvent exhibited the maximum luminance (65.8 cd/m2). The difference between the threshold voltages of the devices ranged up to 6.0 V, despite their fabrication by using solutions with the same composition ratio. The maximal efficiency of the devices fabricated using the DCE solvent was found to be 20 times greater than that of the devices fabricated using TCE solvents. A comparison of the current densities and voltages among devices fabricated using different casting solvents at their maximal efficiencies showed that the maximal efficiencies tended to significantly increase in the order TCE < CHCl3 < DCE solvents at similar voltages (~15 V), despite a lowering of the current density. The current density was considered to be directly related to the number of carriers injected into the device. The above-mentioned observations suggested that the maximal efficiency in these devices was not the hole and electron injection efficiencies, but the values of some parameters subsequent to carrier injection, such as the recombination rate, amount of excitons generated, and the diffusion length. 相似文献
118.
Shiro Usui Nilton Liuji Kamiji Tatsuki Taniguchi Naonori Ueda 《Neural computing & applications》2011,20(7):993-999
With the increasing amount of information available in recent years, searching for the desired content is becoming a challenging
task. In this work, a tool for searching abstracts submitted to scientific conferences is introduced. It not only searches
abstracts by the given keyword(s) but also displays abstracts related to a single or multiple selection. It also displays
highly relevant abstracts together with possible keywords to help users refine their search. Analysis of the conditional similarity
algorithm proposed here has shown that it does provide better output compared to ordinary cosine similarity, as well as the
list of possible keywords reflects results of latent topic analysis. An interface for storing and sorting selected abstracts
for future review and/or printing is also provided. 相似文献
119.
120.
We consider the transient elastoplastic behavior of the functionally graded divertor plate due to a thermal shock with temperature-dependent properties. The development of a micromechanical model for functionally graded materials is presented, and its application to thermoelastoplastic analysis is discussed for the case of the W-Cu functionally graded material for the international thermonuclear experimental reactor divertor plate. The divertor plate consists of a graded layer bonded between a homogeneous substrate and a homogeneous coating, and it is subjected to a cycle of heating and cooling on the coating surface of the material. The material properties of the divertor plate are dependent on the temperature and the position. Numerical results presented include the transient elastoplastic stresses. 相似文献