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101.
Norimasa Nukaga Hirofumi Ono Takuya Shida Hideaki Machida Toshie Suzuki Hiroshi Funakubo 《组合铁电体》2013,141(1):215-222
SrBi 2 Ta 2 O 9 thin films were prepared by ECR plasma enhanced metalorganic chemical vapor deposition (ECR-MOCVD) with a liquid-delivery system using one cocktail source without an additional solvent. The strontium-tantalum double alkoxide, Sr{Ta[OC 2 H 4 H(CH 3 ) 2 ](OC 2 H 5 ) 5 } 2 , was dissolved in stabilized trimethyl bismuth, Bi(CH 3 ) 3 / dioxane. This source system has been used in a conventional bubbling system. Deposition rate and the composition of the films were strictly controlled by the concentration and the composition of the cocktail source. Therefore, high reproducibility was realized by using this system. The constituent phase of the stoichiometric SBT film as-deposited at 500 C on a (111)Pt/TiO 2 /SiO 2 /Si substrate was a fluorite phase and transformed to the single phase of SBT by the post annealing at 800 C. It showed almost the same ferroelectricity as the stoichiometric composition film. 相似文献
102.
Kouichi Asakura Ayuko Iida Ryoichi Kitagata Atsushi Yoshida Shuichi Osanai Akihiro Kuroda 《Journal of surfactants and detergents》2001,4(4):375-378
Adsorption properties of two types of dimethylpolysiloxane backbone derivatives, perfluoroalkyl polyoxyethylenated dimethylpolysiloxane
(FPD) and polyoxyethylenated dimethylpolysiloxane (PD), onto keratin surfaces were investigated. Both polymers are amphiphilic,
since they possess hydrophilic polyoxyethylene groups. FPD contains a perfluoroalkyl group that provides both water-and oil-repellent
properties, whereas PD lacks these groups. Adsorption properties of these polymers onto keratin surfaces are considered a
good index to evaluate these compounds as nonionics used in hair-coating agents, since keratin is a major component of hair.
FPD was more likely to be adsorbed and less likely to be eliminated from the keratin surface than PD. Once FPD had been adsorbed
onto the keratin surface, it was very slowly washed from the surface when it was immersed in stationary water, whereas PD
polymers were quickly washed from the keratin surface. Even in running water, rapid elimination of FPD was not observed. The
strong resistance to loss of FPD after washing with a large quantity of water may be due to the water-repellent nature of
the perfluoroalkyl groups. As a comparison, FPD adsorption onto a glass surface was also investigated. The affinity to the
glass surface was found to be less than to the keratin surface. 相似文献
103.
Jifei Jia Eishi Tanabe Peng Wang Kouichi Ito Hiroyuki Morioka Ye Wang Tetsuya Shishido Katsuomi Takehira 《Catalysis Letters》2001,76(3-4):183-192
A solid phase crystallization (spc) method was applied for the preparation of SrTiO3-supported Ni catalysts and compared to the impregnation (imp) method. spc-Ni0.2/SrTiO3 has highly dispersed and stable Ni metal particles resulting in higher activity and higher sustainability against coking than imp-Ni0.2/SrTiO3 in the partial oxidation of CH4. Both catalysts were tested for the CH4 pyrolysis in order to elucidate the catalytic nature against coking of spc-Ni0.2/SrTiO3. The amount of carbon and the rate of H2 formation were similar over both catalysts at both 773 and 1073 K. On both catalysts, CH4 continuously decomposed at 773 K, while the rate of CH4 pyrolysis quickly decreased at 1073 K. Fibrous carbons grew up with a Ni metal particle on the tip of the fiber at 773 K, while carbon balls and short carbon fibers with a Ni metal particle encapsulated inside formed and no sufficient growth of the fiber was observed at 1073 K. The carbon species formed at 773 K was hydrogenated completely to CH4 around 873 K, while the hydrogenation of that formed at 1073 K needed higher temperature around 1073 K. However, the carbon species formed on both the catalysts at either 773 or 1073 K was completely oxidized around 773 K. Thus, judging from the anti-coking nature, the behaviors in the CH4 pyrolysis are similar over both catalysts, nonetheless spc-Ni0.2/SrTiO3 was far superior to imp-Ni0.2/SrTiO3 in the CH4 oxidation. It is likely that the high sustainability against coking of spc-Ni0.2/SrTiO3 is not due to its intrinsic nature suppressing the coking but due to its high activity of reforming which can quickly eliminate the carbon formed on the catalyst surface. 相似文献
104.
105.
Kouichi Kamiuto 《Applied Energy》1986,23(4):297-305
Two design criteria for unevacuated horizontal multi-layer insulation systems, with equal spacings of the intermediate plates yielding the minimum heat transfer rate, are described. 相似文献
106.
107.
K Higo Y Kubo Y Iwatani T Ono M Maeda H Hiai T Masuda K Kuribayashi F Zhang TY Lamin A Adachi A Ishimoto 《Canadian Metallurgical Quarterly》1997,71(1):750-754
Fv-4 is a mouse gene that dominantly confers resistance to infection with Friend murine leukemia virus (F-MuLV) (S. Suzuki, Jpn. J. Exp. Med. 45:473-478, 1975). Despite complete resistance to ecotropic MuLV infection in mice carrying the Fv-4 gene, it is known that cells carrying the resistance gene in tissue culture do not always show resistance as extensive as that in vivo (H. Yoshikura and T. Odaka, JNCI 61:461-463, 1978). To investigate the immunological effect on resistance in vivo, we introduced the Fv-4 gene into BALB/c nude mice (Fv-4-/- nude[nu/nu]) by mating them with Fv-4 congenic BALB/c mice (Fv-4r/r nude+/+) and examined the susceptibility of the F2 progeny to F-MuLV. All BALB/c nude mice without the Fv-4 gene (Fv-4-/- nude[nu/nu]) were permissive to F-MuLV and developed erythroleukemia within 2 weeks after virus inoculation. The BALB/c nude mice with the Fv-4 gene (Fv-4r/r nude[nu/nu]) did not develop leukemia, and no or little virus was detected in the spleen 7 weeks after virus inoculation. The resistance to F-MuLV was dominant in (Fv-4 congenic BALB/c x BALB/c nude) F1 mice with the Fv-4r/- nude(nu/+) genotype as strictly as in (Fv-4 congenic BALB/c x BALB/c) F1 mice with the Fv-4r/- nude+/+ genotype. However, almost all BALB/c nude mice with the Fv-4r/- nude(nu/nu) genotype developed the disease within 7 weeks, and the virus was detected in all of their spleens even in the mice without leukemia. These results show that the resistance caused by the Fv-4 gene is recessive in nude mice and dominant in BALB/c mice. Some immunological effects, perhaps cell-mediated immunity, may play important roles in the resistance to F-MuLV infection in vivo in addition to the dosage effect of the Fv-4 product. 相似文献
108.
F. Ono S. Komatsu Y. Chimi N. Ishikawa A. Iwase T. Kambara 《Nuclear instruments & methods in physics research. Section B, Beam interactions with materials and atoms》2005,230(1-4):279-283
High-energy ion irradiation was performed using a ring-cyclotron installed at the Institute of Physical and Chemical Research (RIKEN). The incident ions were Ta with the energy of 3.71 GeV, and the fluence was fixed to 5 × 1012 ions/cm2. As a target, three sheets of square plates of Fe–30.2 at.% Ni invar alloys were put one upon another. The shift of the Curie temperature TC of the first sample was 14 K, while that of the second one was 22 K. Comparing these two, the shift was as large as 46 K in the last sample in which ions stopped in the middle. It was concluded that there are at least two different mechanisms that contribute to the shift of TC. 相似文献
109.
Yamazaki S. Ono T. Shimizu H. Kitamura M. Emura K. 《Photonics Technology Letters, IEEE》1990,2(12):914-916
A 2.5-Gb/s CPFSK four-channel FDM transmission experiment has been conducted with a 150-km-long nondispersion-shifted fiber. This system employed a wideband channel space controller, a common polarization control, and a channel identification function. These were indispensable for realizing a high-capacity, coherent FDM trunk line system. The results of the experiment confirm the feasibility of trunk line systems with over 160-Gb/s capacity 相似文献
110.
HY zeolite is a highly active catalyst for the vapor-phase N-alkylation of pyrazoles with alcohols. For example, the reactions
of pyrazole and 4-methylpyrazole with methanol over HY afford N-methylpyrazole and 1,4-dimethylpyrazole, respectively, in
a 100% yield at 573 K.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献