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61.
62.
Toshiyuki Hirano Masaharu Yamaguchi Toshimi Yamane 《Metallurgical and Materials Transactions B》1974,5(5):1249-1250
In the two phase alloys which exhibit superplasticity, strain rate sensitivitym, in the relationship σ =Kε
m, has been known to be strongly dependent on the volume fraction of the second phase. It, however, has not been necessarily
confirmed experimentally on various two phase alloys. In this paper we present an experimental evidence showing that the largestm is obtained when the volume fraction of the second phase is around 0.5. 相似文献
63.
Yasutaka Nagai Kazuhiko Dohmae Kentaro Teramura Tsunehiro Tanaka Gemma Guilera Kazuo Kato Masaharu Nomura Hirofumi Shinjoh Shinichi Matsumoto 《Catalysis Today》2009,145(3-4):279
Two main pivotal subjects of research in automotive catalysts were studied by modern X-ray absorption analysis techniques. One is oxygen storage/release behaviour, and the other is sintering inhibition of Pt particles. First, three types of CeO2–ZrO2 (Ce:Zr = 1:1 molar ratio) compounds with different oxygen storage/release capacities and different structural properties were prepared, and the valence change of Ce as a function of temperature during oxygen release/storage processes was investigated. The reduction of surface Ce mainly occurred in the range 100–170 °C, and the reduction of bulk Ce progressed at high temperatures of 170 °C and above. The Ce reduction behaviour depended not only on the homogeneity of the Ce and Zr for bulk reduction at high temperatures but also on the particle size of the CeO2–ZrO2 samples for surface reduction at low temperatures. Secondly, sintering inhibition of Pt in Pt/Al2O3, Pt/MgO and Pt/ceria-based catalysts after 800 °C ageing in air was studied. We found that the Pt–O–M (M = Mg, Ce) bond acted as an anchor and inhibited the sintering of Pt particles on MgO or ceria-based oxide. Especially, it was noteworthy that the Pt–O–Ce4+ bond on the ceria-based support breaks easily through the reduction of Ce (Ce4+ → Ce3+) during the usual stoichiometric and reducing conditions. 相似文献
64.
Murata H Futami J Kitazoe M Kosaka M Tada H Seno M Yamada H 《Journal of Bioscience and Bioengineering》2008,105(1):34-38
Polyethylenimine (PEI) cationization is a powerful strategy for protein transduction into cells. In this study, we attempted the artificial regulation of cell proliferation by protein transduction of the N-terminal domain (1-132 amino acids) of the simian virus 40 large T-antigen (SVLT-N), which inactivates retinoblastoma family proteins but not p53. To deliver SVLT-N into cells, we employed an indirect cationization method by forming a complex of biotynylated SVLT-N through disulfide bonds (biotin-SS-SVLT-N) and PEI-cationized avidin (PEI600-avidin). Using this complex, SVLT-N was transduced into the nucleus of confluent and quiescent Balb/c 3T3 cells and was found to be complexed with a cellular target protein, pRb. Furthermore, SVLT-N transduction induced cell proliferation in spite of confluent conditions. Because SVLT-N thus transduced into cells gradually degraded and was not detectable after a 4-d incubation, transiently transformed cells were obtained by this method. These results suggest that oncogene protein transduction technology has great potential for in vitro regulation of cell proliferation. 相似文献
65.
Phytoextraction by a high-Cd-accumulating rice: reduction of Cd content of soybean seeds 总被引:1,自引:0,他引:1
Murakami M Ae N Ishikawa S Ibaraki T Ito M 《Environmental science & technology》2008,42(16):6167-6172
Soybeans (Glycine max (L) Merr.) are the major summer crop grown in Japanese upland fields (characterized by aerobic soil) that have been converted from paddies. To evaluate the effect of phytoextraction by rice on the seed cadmium (Cd) content of soybeans grown subsequently, we grew Milyang 23, a high-Cd-accumulating rice cultivar, and then grew soybeans in three paddy soils contaminated with moderate Cd concentrations (2.50-4.27 mg Cd kg(-1)). The rice accumulated 7-14% of the total soil Cd in its shoots. The soybean seed Cd contents were 24-46% less than those grown on control soils. Phytoextraction by Milyang 23 rice is thus a promising remediation method for reducing seed Cd contents of soybeans grown on paddy soils under aerobic soil conditions. 相似文献
66.
Evaluation and Identification of Potent Angiotensin‐I Converting Enzyme Inhibitory Peptide Derived from Dwarf Gulper Shark (Centrophorus atromarginatus)
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67.
Kawai T Chun WJ Asakura K Koike Y Nomura M Bando KK Ted Oyama S Sumiya H 《The Review of scientific instruments》2008,79(1):014101
The design and performance of a new high-pressure and high-temperature cell for measurement of x-ray absorption fine structure (XAFS) spectra of solid catalysts working in a flowing liquid are presented. The cell has flat, high-purity sintered cubic boron nitride (c-BN) windows which can tolerate high temperature (900 K) and high pressure (10 MPa). The c-BN is a new material which has the highest tensile strength, second only to diamond, and is also chemically and thermally stable. The use of the cell is demonstrated for measurements of PtPdAl(2)O(3) and Ni(2)PSiO(2) hydrodesulfurization catalysts at reaction conditions. A technique called delta chi (Deltachi), involving determining the difference between XAFS spectra of the sample at reaction conditions and the bare sample, is introduced. 相似文献
68.
Alkali halide added transition metal oxides produced ethylene selectively in oxidative coupling of methane. The role of alkali halides has been investigated for LiCl-added NiO (LiCl/NiO). In the absence of LiCl the reaction over NiO produced only carbon oxides (CO2 + CO). However, addition of LiCl drastically improved the yield of C2 compounds (C2H6 + C2H4). One of the roles of LiCl is to inhibit the catalytic activity of the host NiO for deep oxidation of CH4. The reaction catalyzed by the LiCl/NiO proceeds stepwise from CH4 to C2H4 through C2H6 (2CH4 → C2H6 → C2H4). The study on the oxidation of C2H6 over the LiCl/NiO showed that the oxidative dehydrogenation of C2H6 to C2H4 occurs very selectively, which is the main reason why partial oxidation of CH4 over LiCl/NiO gives C2H4 quite selectively. The other role of LiCl is to prevent the host oxide (NiO) from being reduced by CH4. The catalyst model under working conditions was suggested to be the NiO covered with molten LiCl. XPS studies suggested that the catalytically active species on the LiCl/NiO is a surface compound oxide which has higher valent nickel cations (Ni(2+δ)+ or Ni3+). The catalyst was deactivated at the temperatures>973 K due to vaporization of LiCl and consumption of chlorine during reaction. The kinetic and CH4---CD4 exchange studies suggested that the rate-determining step of the reaction is the abstraction of H from the vibrationally excited methane by the molecular oxygen adsorbed on the surface compound oxide. 相似文献
69.
Tomohito Hamazaki Eisuke Takazakura Kenzo Osawa Masaharu Urakaze Saburo Yano 《Lipids》1990,25(9):541-545
Eicosapentaenoic acid (EPA) ethyl ester (1.8 g/d) was administered to 16 diabetic patients (5 insulin-dependent and 11 noninsulin-dependent
diabetics) for 6 mon. EPA in total plasma fatty acids increased from 4.0±2.4 mol% (mean±SD) to 7.5±3.1 mol% (p<0.001). Albumin
excretion, measured with spot urine, was significantly reduced from 65 to 36 mg/g creatinine (geometric means, p<0.001). Fasting
blood sugar levels, glycohemoglobin, body weight and blood pressure did not change significantly during the study. There were
also no significant changes in serum levels of creatinine, urea nitrogen, total cholesterol and triglycerides. Although no
overt hemorrhage was observed in the patients, hematocrit was reduced from 42.6±2.8% to 41.0±3.9% (p<0.02). Ten other similar
diabetic patients (4 insulin-dependent and 6 non-insulin-dependent diabetics) were followed as a reference group, not concomitantly,
for 6 mon with neither EPA ethyl ester nor placebo. The parameters mentioned above were not changed significantly in this
group during 6 mon. EPA administration might retard the appearance of overt diabetic nephropathy. 相似文献
70.
Hiroki Ago Naoyasu Uehara Masaharu Tsuji Motoo Yumura Toshihiko Setoguchi 《Carbon》2006,44(14):2912-2918
Changes in the gas composition during the methane chemical vapor deposition growth of single- and double-walled carbon nanotubes over metal-supported MgO catalysts were investigated in an attempt to increase the nanotube yield. Monitoring the gas composition by gas chromatography as a function of the reaction time provides information on the activity and lifetime of the catalyst. The degree of methane decomposition, i.e., the C-H bond dissociation, was closely related to the nanotube yield, and the Fe-Mo binary catalyst exhibited a high activity. The effects of water vapor on the catalytic nanotube growth were also studied by introducing water vapor in the inlet gas. An appropriate amount of water prolonged the lifetime of the catalyst and increased the nanotube yield by 35%. 相似文献