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排序方式: 共有485条查询结果,搜索用时 15 毫秒
151.
Kentaro Yamato Kazuo Tominaga Wataru Takashima Keiichi Kaneto 《Synthetic Metals》2009,159(9-10):839-842
Electrochemomechanical strain (ECMS) of conducting polymers, polypyrrole (PPy) films was studied using several kinds of ionic liquids and the mixed solution with organic solvents from the view points of strain and stability. The PPy films, which were electrodeposited from lithium bis(trifluoromethanesulfonyl)imide (LiTFSI), showed porous morphology. The ECMS in the films operated in ionic liquids was less than 5%, demonstrating a cation movement behavior and stable cycling. By the operation in ionic liquid/propylene carbonate (PC) mixed solution, the ECMS increased up to 24% showing the anion movement, and gradually decreased upon cycling to 16% at 10th cycle. The strain and stability of the ECMS in mixed electrolyte solution with various ratios of the ionic liquid and PC were studied and discussed in terms of mechanisms of ECMS in mixed solutions. 相似文献
152.
Mechanisms that regulate the movement of a membrane spanning protein band 3 in erythrocyte ghosts were investigated at the level of a single or small groups of molecules using single particle tracking with an enhanced time resolution (0.22 ms). Two-thirds of band 3 undergo macroscopic diffusion: a band 3 molecule is temporarily corralled in a mesh of 110 nm in diameter, and hops to an adjacent mesh an average of every 350 ms. The rest (one-third) of band 3 exhibited oscillatory motion similar to that of spectrin, suggesting that these band 3 molecules are bound to spectrin. When the membrane skeletal network was dragged and deformed/translated using optical tweezers, band 3 molecules that were undergoing hop diffusion were displaced toward the same direction as the skeleton. Mild trypsin treatment of ghosts, which cleaves off the cytoplasmic portion of band 3 without affecting spectrin, actin, and protein 4.1, increased the intercompartmental hop rate of band 3 by a factor of 6, whereas it did not change the corral size and the microscopic diffusion rate within a corral. These results indicate that the cytoplasmic portion of band 3 collides with the membrane skeleton, which causes temporal confinement of band 3 inside a mesh of the membrane skeleton. 相似文献
153.
Dorozhkin PS Tovstonog SV Golberg D Zhan J Ishikawa Y Shiozawa M Nakanishi H Nakata K Bando Y 《Small (Weinheim an der Bergstrasse, Germany)》2005,1(11):1088-1093
Temperature control on the nanometer scale is a challenging task in many physical, chemical, and material science applications where small experimental volumes with high temperature gradients are used. The crucial difficulty is reducing the size of temperature sensors while keeping their sensitivity, working temperature range, and, most importantly, their simplicity and accuracy of temperature reading. In this work, we demonstrate the ultimate miniaturization of the classic thermometer using an expanding column of liquid gallium inside a multi-walled C nanotube for precise temperature measurements. We report that electrical conductivity through unfilled nanotube regions is diffusive with a resistance per unit length of approximately 10 kOmega microm(-1), whereas Ga-filled segments of the nanotube show metallic behavior with a low resistance of approximately 100 Omega microm(-1). No noticeable Schottky barrier exists between the nanotube carbon shell and the inner Ga filling. Based on these findings, an individual carbon nanotube partially filled with liquid Ga is used as a temperature sensor and/or switch. The nanotube's electrical resistance decreases linearly with increasing temperature as the metallic Ga column expands inside the tube channel. In addition, the tube resistance drops sharply when two encapsulated Ga columns approaching each other meet inside the nanotube, producing a switching action that can occur at any predetermined temperature, as the Ga column position inside the nanotube can be effectively pre-adjusted by nanoindentation using an atomic force microscope. 相似文献
154.
Keiichi Honda 《Journal of chemical ecology》1980,6(5):867-873
Benzaldehyde, phenylacetaldehyde (major component), 2-phenylpropenal,n-heptanal, 6-methylhept-5-en-2-one, and linalool were identified as compounds responsible for the male scent ofAtrophaneura alcinous alcinous. These substances were present predominantly in the wings, and the quantity of them was largest at the inner margin of the hind wing. Female wings also contained some of them in much smaller (except a few components) amounts. The relative proportion of each component exhibited manifests sexual differences. 相似文献
155.
156.
sec-Butanol was employed to prepare etherified methylol–melamine resins to be used in the coatings industry as crosslinking agents. Difficulties associated with slow rate of etherification as compared to the rate of polycondensation of methylol–melamine were overcome by finding the determining factors which controlled the two competitive reactions independently. Attempts were made to interpret the effects of various factors from a mechanistic point of view. 相似文献
157.
Lin Li Syuma Yasuzuka Yufeng Weng Keiichi Yokogawa Tsutomu Fujimoto Toyonari Sugimoto Hideki Fujiwara Toshiki Hayashi Takashi Hiraoka Keizo Murata 《Journal of Low Temperature Physics》2006,142(3-4):473-476
Hall resistance and magnetic torque measurements have been carried out in the field-induced spin-density-wave (FISDW) phase
of deuterated (TMTSF)2ClO4 for various cooling rates through the anion ordering temperature. We have found that the Hall resistance in the intermediate
cooled state shows a phase transition from the non-quantized Hall phase to the quantized Hall phase (n=1) with hysteresis.
We have also found that the magnetic torque in the non-quantized Hall phase rapidly decreases with increasing cooling rate.
These results suggest that there is a new phase transition from the non-quantized Hall phase to the quantized Hall phase in
(TMTSF)2ClO4. 相似文献
158.
Keiichi Kamada Kouichi Nawashiro Fumiyasu Tamagawa Cha-Yeol Lee Hiroshi Yoshida Sunao Kawasaki Ritoku Ando Masaru Masuzaki 《Journal of Infrared, Millimeter and Terahertz Waves》2000,21(9):1441-1449
A relativistic electron beam (500 keV, 200 A, 10 ns) generated magnetically tunable microwave radiation in a frequency range of 9-13 GHz when it is injected into an X-band rectangular waveguide immersed in a uniform axial magnetic field (4-10 kG). The mechanism of the microwave radiation was identified as the gyrotron backward wave interaction. The output power of the radiated microwave increased exponentially with the increase of the cavity length. 相似文献
159.
Yuichi Matsuo Yusuke Yoshinaga Yasushi Sekine Keiichi Tomishige Kaoru Fujimoto 《Catalysis Today》2000,63(2-4):439-445
The effect of fluidized bed reactor in autothermal CO2 reforming of methane over NiO–MgO solid solution catalysts was investigated by comparing with fixed bed reactor. Methane conversion to syngas was drastically enhanced by using a fluidized bed reactor. The catalyst was reduced and oxidized repeatedly in fluidized bed reactor during the reaction. The enhancement of methane conversion is related to the catalyst reducibility. 相似文献
160.