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排序方式: 共有391条查询结果,搜索用时 15 毫秒
91.
Kazuhiro Saito Mitsuru Yoneyama Mitsuyoshi Saito Keiichi Ikegami Michio Sugi
Takayoshi Nakamura
Mutsuyoshi Matsumoto Yasujiro Kawabata 《Thin solid films》1988,160(1-2):133-137Photoelectric cells based on Langmuir-Blodgett (LB) films were fabricated using dye monolayers as photoconductors and N-docosylpyridinium-di(tetracyanoquinodimethane) (PT) monolayers as one of the electrode materials. It is found that PT films can be used as a wiring material instead of large work function metals such as silver or Ni-Cr. However, in comparison with the photoelectric cells using the conventional metals, a few different properties were observed for those wired with PT. These differences are assignable to the difference between the LB film-metal and the LB film-LB film contacts. 相似文献
92.
93.
H. Mori H. Miyoshi K. Takeda H. Yoneyama H. Fujita Y. Iwata Y. Otsuka Y. Murata 《Journal of Materials Science》1992,27(12):3197-3199
The microstructures of iron oxide-pillared montmorillonite have been investigated by highresolution transmission electron microscopy. The iron oxide is incorporated in the interlayer space of montmorillonite as Fe2O3 crystallites. The crystallites are present in two different morphologies: isolated particles 10 nm long and 4 nm thick, and bands (possibly plates) with a thickness 1 nm running parallel to the basal plane. 相似文献
94.
In order to improve the mechanical properties of polypropylene film, a new processing combining extrusion and zone-annealing has been applied. It was found that there are suitable conditions for each step in the combined processing. When the coextrusion draw ratio was low, the total draw ratio and modulus could be increased by the zone-annealing subsequently done. The highest modulus was obtained when the film was coextruded at extrusion draw ratio 4 and then zone-annealed at 120°C under 7 kg/mm2. The value was 12 GPa in Young's modulus or 17 GPa in dynamic modulus. The peak temperature of αc dynamic dispersion for the combinedly processed film was 109°C, which is higher by 10°C than that for the as-coextruded film. Four drawing methods were compared in dynamic viscoelasticity. These methods are the coextrusion, zone-drawing/zone-annealing, two-step coextrusion, and the combined processing by coextrusion and zone-annealing. The highest dynamic modulus for each method was arranged in the above order. The combined processing indicated the most effective improvement in mechanical properties, because it is believed that lamellae in the original film were broken by cooperating interaction of shear stress, compression, and tension on coextrusion and then the superstructure with a high crystallinity and a high molecular orientation was formed on zone-annealing. 相似文献
95.
The adsorption of various alkylammonium cations was investigated by measurement of the interfacial tension. Tetraethanolammonium ions (HOC2H4)4N+ showed weaker adsorbability than that expected from its ionic radius. The adsorbabilities (relative surface excess of cation FΓ+ and charge of specifically adsorbed cation q1+) of the ethyl series (C2H5)nH4?nN+(n = 0 ≈ 4), and of the methyl series (CH3)nH4?nN+n = 0 ≈ 3) were directly proportional to the hydration enthalpies of these cations - ΔH0h, but the proportionalities were different between the methyl and the ethyl series. A linear relation was, however, found between FΓ+ and the hydration entropies - ΔS0h without regard to the kinds of cations. A similar relation was also found between q1+? - ΔS0h. In conclusion, the adsorbabilities of these cations were governed by the hydration entropy, not by the hydration enthalpy. 相似文献
96.
Teruhisa Satsuki Kenji Umehara Yuji Yoneyama 《Journal of the American Oil Chemists' Society》1992,69(7):672-677
The detergency properties of α-sulfonated fatty acid methyl esters (α-SFMe) were evaluated and compared to those of conventional
anionic surfactants by using a model heavy-duty detergent formulation. Several physicochemical properties of surfactants were
measured to investigate the effective factors on detergency. α-SFMe showed good detergency performance under various washing
conditions. These results were considered to correlate well with the good adsorption behavior on oils and dispersing capabilities
for particles, as well as with the good solubilization capacity. Solubilization behavior of α-SFMe is discussed in relation
to micelle properties. It is suggested that α-SFMe can form suitable micelles for solubilizing polar oils advantageously,
due to its bulky hydrophilic group. 相似文献
97.
A new reaction route of methanol synthesis at low temperature from CO2-containing syngas with Cu/ZnO catalyst and the aid of alcohols has been developed in a batch and a flow-type semi-batch reactors. The use of alcohols as catalytic solvents realized methanol synthesis at 443 K with formate as an intermediate. The activity of methanol synthesis depends on types and structures of alcohols. Among all alcohols, 2-alcohol exhibited the highest activity. With the aid of 2-butanol, the one-pass 47.0% conversion and 98.9% selectivity were achieved at a mild condition, 443 K and 50 bar. The new reaction route of methanol synthesis is a practical method for near future technology. 相似文献
98.
Masaki Matsui Masaya Kotani Yasuhiro Kubota Kazumasa Funabiki Jiye Jin Tsukasa Yoshida Shinji Higashijima Hidetoshi Miura 《Dyes and Pigments》2011,91(2):145-152
The cell performance of novel benzoindoline dyes on zinc oxide prepared by template cathode electro-deposition method was compared with that of known indoline dyes. Among cyanoacrylic, single and double rhodanine acetic acid derivatives, the cyanoacrylic benzoindoline dye showed better performance than the indoline dye (D131) due to larger Jsc value which comes from its positive Eox level and bathochromic UV-vis absorption band. 相似文献
99.
Polymer composite membranes composed of anion conductive polymer nanofiber mats and the corresponding polymer matrix were prepared and characterized for future alkaline fuel cells. In this paper, electrospinning was attempted to fabricate anion conductive nanofiber mats. The anion conductivity of the composite membrane was higher than the corresponding membrane without nanofibers under all conditions due to outstanding anion conductive characteristics of the nanofibers. In addition, because of the rigid and anisotropic structure of the nanofibers, membrane stabilities such as reductive degradation resistance and mechanical strength were very much improved. The gas permeability and excessive hydration swelling that will degrade fuel cells after long‐term operation were suppressed in the nanofiber composite membrane. These results indicated that excellent properties of the anion conductive nanofibers were demonstrated even in the composite membrane, leading to the potential application of anion conductive nanofibers in future fuel cells. © 2016 Society of Chemical Industry 相似文献
100.
Yoshiharu Yoneyama Xiaoyu Sun Tiansheng Zhao Tiejun Wang Toshiaki Iwai Koichi Ozaki Noritatsu Tsubaki 《Catalysis Today》2010,149(1-2):105-110
To produce isoparaffins from synthesis gas directly, modified Fischer–Tropsch (FT) synthesis was carried out under supercritical conditions using n-butane as a medium. One-step FT synthesis using a hybrid catalyst consisting of Co/SiO2, HZSM-5 and Pd/SiO2 was carried out. Introduction of supercritical-phase n-butane increased light isoparaffins significantly and suppressed the formation of the by-product, methane. Under supercritical-phase butane, hydrogenolysis and isomerization reactions were promoted. Due to the fact that the optimum temperatures for FT and HZSM-5 catalysts are different, 513 K and over 573 K, respectively, two-step FT synthesis was also carried out to optimize the reaction temperatures. The first-step reaction used Co/SiO2 catalyst containing small amount of HZSM-5 for FT synthesis at 513 K, and the second-step reaction used a hybrid catalyst containing Pd/SiO2 and zeolite for hydrogenolysis and isomerization of hydrocarbons at 573 K. Introduction of supercritical n-butane increased the isoparaffin selectivity, and decreased the methane selectivity significantly. The production of heavy hydrocarbons C9+ was inhibited in both gas and supercritical phase. The isoparaffin selectivity in the gas phase decreased with time-on-stream, but very stable for the supercritical-phase reaction. Because water and heavy hydrocarbons were removed from active sites on zeolite and the zeolite acidity was promoted in the supercritical medium, the selectivity of isoparaffin was considered stable. Among zeolites added to the hybrid catalyst in the second-step reactor, HZSM-5 and H-beta zeolite were suitable for producing light isoparaffins. These results indicated that two-step FT synthesis under supercritical n-butane was superior for producing light isoparaffins from synthesis gas directly. 相似文献