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31.
Shin-ichi Inomata Mitsuaki Komoda Hayaki Watanabe Masashi Nomura Tetsu Ando 《Journal of chemical ecology》2000,26(2):443-454
Anadevidia peponis and Macdunnoughia confusa are defoliators of plants in the family Cucurbitaceae and Compositae, respectively, in Japan. GC-MS analyses of crude pheromone gland extracts treated with or without dimethyl disulfide indicated that females of A. peponis produced six monoene acetates and two monoene alcohols and that M. confusa females produced five monoene acetates. These components include (Z)-7-dodecenyl acetate as a major common constituent and three other acetates as minor common constituents. The minor constituents are quite different in blend composition. In addition, with (Z)-7-dodecenyl acetate, an indispensable component for male attraction is (Z)-5-decenyl acetate for A. peponis and (Z)-9-tetradecenyl acetate is essential for M. confusa. Field tests with synthetic lures showed synergistic effects of some other minor components and male attraction of three additional Plusiinae species, Macdunnoughia purissima, Ctenoplusia albostriata, and Chrysodeixis eriosoma, suggesting their reproductive isolation is based in part on pheromonal communication. 相似文献
32.
Qing-qing LU Takuto KANETSUKI Shin-ichi YAMASAKI Ryoichi YAMADA Takahiro WATANABE Noriyoshi TSUCHIYA 《中国有色金属学会会刊》2014,24(6):1880-1889
Focusing on the origin of the heavy metal, this study aims to build an imputed method to estimate the heavy metal content in river water by making a distinction between the heavy metal of natural origins and that caused by human activities. Supported by GIS, Kosaka watershed within the Hokuroku basin was divided into several sub-watershed polygons and the outflows of water and Cu were calculated for each polygon. Compared with the natural origin, the dominant Cu emissions affected the river water more significantly in local. Based on the mass balance closure, the heavy metal content of Cu in the Kosaka River was estimated by the conflux accumulation of tributaries and mine drainages. The estimated Cu concentrations were checked by comparing with the actually measured values at monitoring points along the Kosaka River and the results are coincidence with each other in general. It is revealed that the mainstream water quality could be estimated by seizing the water quality of upstream tributaries and human drainages. 相似文献
33.
Hajime Yano Daigo Kouro Naoki Sasaki Shin-ichi Muramatsu 《Solar Energy Materials & Solar Cells》2009,93(6-7):976-979
We have found that the short-circuit current, Jsc, of polymer/fullerene [RR-P3HT/C60] solar cells has a clear dependence on the surface roughness of the ITO/glass substrate. We prepared an ITO surface with an average roughness, Ra, of 0.7–11 nm by chemical etching. At first Jsc increases with the increase in ITO surface roughness and then gradually decreases. The maximum performance was obtained at Ra≈4 nm. Jsc is also high with a very flat surface of Ra=0.7 nm. This feature can be attributed to the trade-off between the increase in absorption light path length and film-quality deterioration. 相似文献
34.
Hidetoshi Miyazaki Shin-ichi Kikitsu Hisao Suzuki Toshitaka Ota 《Advanced Powder Technology》2011,22(4):544-547
In an effort to improve energy-efficient windows, we experimented with a precursor slurry composite by using needle-like TiO2 particles as the filler in a urethane matrix. Applying dc bias to the slurry failed to array the needle-like particles in the composite and to deposit on the film surface because of electrophoretic movement. However, applying ac bias of ±5 V to the precursor slurry composite for 12 h resulted in the needle-like TiO2 particles being arrayed in the composite in a direction normal to the film surface. This resulted in an improvement in the energy efficiency of the material through an angular dependence of transmittance in the visible–near-infrared range. 相似文献
35.
Effect of Excess PbO on the Densification of PLZT Ceramics 总被引:1,自引:0,他引:1
Byung-Moo Song Doh-Yeon Kim Shin-ichi Shirasaki Hiroshi Yamamura 《Journal of the American Ceramic Society》1989,72(5):833-836
The densification behavior and electrical properties of PLZT ceramics as a function of excess PbO in the starting powder have been investigated. The hot-pressed PLZT ceramics, prepared from powders containing 0% to 4% excess PbO, were transparent, and their electrical properties were similar in general. PLZT with PbO deficiency up to 1.4 mol% from stoichiometry can be regarded as a single phase-PLZT. 相似文献
36.
Takatoshi Yamada Kumaragurubaran Somu Christoph E. Nebel Shin-ichi Shikata 《Diamond and Related Materials》2008,17(4-5):745-748
Vacuum anneal treatments effects on field emission properties of phosphorus doped diamond are discussed. The C1s core level of diamond is characterized by X-ray photoelectron spectroscopy (XPS). With increasing annealing temperature, firstly oxygen desorption takes place from surface, which induce surface reconstruction followed by graphitization of surface. Field emission properties, therefore, strongly depend on vacuum anneal temperature. The threshold voltage of diamond annealed at 900 °C is the lowest. Fowler–Nordheim plots indicate that diamond annealed at 900 °C has the lowest barrier height, which is in good agreement with electron affinities as measured on carbon reconstructed surface. Further increased annealing temperature induces surface graphitization, which causes a threshold voltage increase of field emission. 相似文献
37.
Naoko Fujiwara Shin-ichi YamazakiZyun Siroma Tsutomu IoroiKazuaki Yasuda 《Journal of power sources》2007
l-Ascorbic acid (AA) was directly supplied to polymer electrolyte fuel cells (PEFCs) as an alternative fuel. Only dehydroascorbic acid (DHAA) was detected as a product released by the electrochemical oxidation of AA via a two-electron transfer process regardless of the anode catalyst used. The ionomer in the anode may inhibit the mass transfer of AA to the reaction sites by electrostatic repulsion. In addition, polymer resins without an ionic group such as poly(vinylidene fluoride) and poly(vinyl butyral) were also useful for reducing the contact resistance between Nafion membrane and carbon black used as an anode, although an ionomer like Nafion is needed for typical PEFCs. A reaction mechanism at the two-phase boundaries between AA and carbon black was proposed for the anode structure of DAAFCs, since lack of the proton conductivity was compensated by AA. There was too little crossover of AA through a Nafion membrane to cause a serious technical problem. The best performance (maximum power density of 16 mW cm−2) was attained with a Vulcan XC72 anode that included 5 wt.% Nafion at room temperature, which was about one-third of that for a DMFC with a PtRu anode. 相似文献
38.
This paper reports on a new technique of measurements of microbubble position in three dimensions with high time-resolution. The technique is based on micro digital holographic particle tracking velocimetry. In this technique, an intensity profile is constructed from a holographic image of a microbubble where the profile results in showing two peaks. The distance between the two peaks appears to relate to the size of the microbubble's diameter. The three-dimensional position of the bubble can be detected by the center of the two peaks and the center point of the bubble image focused by a digital hologram. We also theoretically obtained the intensity profile of a microbubble by considering a refraction of light on a bubble surface to a ring-shaped aperture model. The theoretically obtained distance between the two peaks is found to be in good agreement with the values obtained experimentally. 相似文献
39.
Yasuo Y. Suzuki Shin-ichi Saito Susumu Kurihara 《Journal of Low Temperature Physics》1998,113(5-6):897-902
We investigated the ground state of the infinite dimensional Hubbard model for both attractive and repulsive interactions by applying Gutzwiller type variational wave functions. Our variational wave functions have lower energies than the simple BCS wave function for the attractive case, and lower energies than the Brinkman-Rice state for the repulsive case. We found that the system has several phases depending on the density of electrons and the interaction strength. Investigated phases include antiferromagnetic, Fermi liquid, superconducting, charge density wave, and supersolid phases. The last one is a coexistence phase of superconducting and charge density wave states. 相似文献
40.
Hisanori Tanaka Shin-ichi Ito Satoshi Kameoka Keiichi Tomishige Kimio Kunimori 《Applied Catalysis A: General》2003,250(2):255-263
K-promoted Rh/USY (molar ratio: K/Rh=3) catalyst was found to exhibit high performance in preferential oxidation of CO in rich hydrogen. Such high performance was maintained in the presence of steam and CO2. The CO oxidation activity of the K-Rh/USY catalyst was independent of the partial pressure of H2, while the activity of the unpromoted Rh/USY catalyst was decreased significantly in hydrogen-rich stream. The effect of potassium addition on the catalyst structure was investigated and is discussed in terms of the differences in the catalytic performance. 相似文献