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101.
Takeshi Ando Eiichi Ohki Yasutaka Nakashima Yutaka Akita Hiroshi Iijima Osamu Tanaka 《Advanced Robotics》2013,27(15):1727-1746
The article describes the development of a gait phase time-based split-belt treadmill measurement system. Conventional methods of measuring gait phase, such as the foot switch and force plate, require significant preparation and are costly. In this article, we propose a simple, cheap, and accurate gait phase measurement system that utilizes only the treadmill motor current value. Comparison of this algorithm with conventional methods reveals that the proposed algorithm is as accurate as the foot switch. Moreover, the proposed algorithm can estimate stance phase within a 0.2?s error of the measured value of the force plate in most cases (four out of five healthy subjects). This accuracy is higher than that of the foot switch which is widely used in the clinical field. 相似文献
102.
Manabu Shimada Heru Setyawan Yutaka Hayashi Nobuki Kashihara Kikuo Okuyama Sugeng Winardi 《Aerosol science and technology》2013,47(5):408-414
The effects of gas flow rate on particle formation and film deposition during the preparation of silica thin film using a TEOS/O2 plasma were investigated. Particle formation and growth are suppressed with increasing gas flow rates. The film deposition rate increases with increasing gas flow rate, reaches a maximum value, and eventually decreases again. However, the uniformity of the film tends to degrade at high gas flow rates. At a high gas flow rate, some particles trapped in the sheath near the grounded electrode pass through the sheath to reach the substrate and are then embedded in the growing film. A self-consistent sheath model combined with particle force balance based on charge fluctuation was developed to explain these experimental findings qualitatively. The model reveals that charge fluctuation is a key factor for the particle to overcome the potential barrier of the negatively charged particles to pass through the sheath, eventually reaching the substrate. The model further shows that the probability of a particle being deposited on the substrate is higher for increased gas flow rates, which correctly predicts the experimentally observed trend. 相似文献
103.
Joji Ohshita Yosuke Tada Atsutaka Kunai Yutaka Harima Yoshihito Kunugi 《Synthetic Metals》2009,159(3-4):214-217
Hole-injection properties of annealed poly(alkoxy- and alkylthiophene) films in OLEDs were studied. Among them, annealed poly(3,3′-dihexyloxy-2,2′-bithiophene) (aPHOBT) film exhibited good hole-injection properties and a triple-layered OLED with the structure ITO/aPHOBT/PVK/Alq3/Mg–Ag (device I) showed much higher performance than a double-layered device without the aPHOBT layer (device II, ITO/PVK/Alq3/Mg–Ag). Device I was slightly inferior to a device having a PEDOT–PSS layer as the hole injector (device III, ITO/PEDOT– PSS/PVK/Alq3/Mg–Ag) in the low-intermediate region of the applied voltage (6–11 V), but gave comparable luminance to III when the applied voltage exceeded 11 V. 相似文献
104.
Chlorophyll-a (Chl-a) assembled in hydrophobic domain by fatty acid with long alkyl hydrocarbon chain such as myristic acid (Myr), stearic acid (Ste) and cholic acid (Cho) modified onto nanocrystalline TiO2 electrode is prepared and the photovoltaic properties of the nanocrystalline TiO2 film by Chl-a are studied. Incident photon to current efficiency (IPCE) value at 660 nm in photocurrent action spectrum of Chl-a/Ste-TiO2, Chl-a/Myr-TiO2 and Chl-a/Cho-TiO2 electrodes are 5.0%, 4.1% and 4.1%, respectively. Thus, the IPCE is maximum using Chl-a/Ste-TiO2 electrode. From the results of photocurrent responses with light intensity of 100 mW cm−2 irradiation or monochromatic light with 660 nm, generated photocurrent increases using Chl-a/Ste-TiO2 electrode compared with the other Chl-a assembled TiO2 electrodes. These results show that the hydrophobic domain formed by stearic acid with long alkyl hydrocarbon chain is suitable for fixation of Chl-a onto TiO2 film electrodes and photovoltaic performance is improved using Chl-a onto Ste-TiO2 film electrode. 相似文献
105.
Periodical shedding of cloud cavitation from a single hydrofoil in high-speed cryogenic channel flow
In order to explain criteria for periodical shedding of the cloud cavitation, flow patterns of cavitation around a plano-convex
hydrofoil were observed using a cryogenic cavitation tunnel of a blowdown type. Two hydrofoils of similarity of 20 and 60
mm in chord length with two test sections of 20 and 60 mm in width were prepared. Working fluids were water at ambient temperature,
hot water and liquid nitrogen. The parameter range was varied between 0.3 and 1.4 for cavitation number, 9 and 17 m/sec for
inlet flow velocity, and −8° and 8° for the flow incidence angle, respectively. At incidence angle 8°, that is, the convex
surface being suction surface, periodical shedding of the whole cloud cavitation was observed on the convex surface under
the specific condition with cavitation number and inlet flow velocity, respectively, 0.5, 9 m/sec for liquid nitrogen at 192°C
and 1.4, 11 m/sec for water at 88°C, whereas under the supercavitation condition, it was not observable. Periodical shedding
of cloud cavitation occurs only in the case that there are both the adverse pressure gradient and the slow flow region on
the hydrofoil. 相似文献
106.
ZrB2 platelets were prepared by mechanochemical processing a zirconium (IV) chloride–boron mixture with subsequent annealing from 800 °C to 1200 °C. The phases present were identified by X-ray diffraction. The size and morphology of the synthesized ZrB2 powders were characterized by scanning electron and transmission electron microscopy. At 800 °C, ZrO2 was detected in absence of ZrB2. At or above 1000 °C, ZrCl4–B converted to ZrB2. Moreover, at 1200 °C, ZrCl4–B completely converted to ZrB2 without trace quantities of residual ZrO2. The synthesized ZrB2 consisted of platelets with a diameter of 0.1–2.1 μm and a thickness of 40–200 nm. 相似文献
107.
Shuqi Guo Ramasamy Sivakumar Hideaki Kitazawa Yutaka Kagawa 《Journal of the American Ceramic Society》2007,90(5):1667-1670
Fully dense multiwall carbon nanotubes (MWCNT)/SiO2 nanocomposites with MWCNTs contents of 5 and 10 vol% have been processed by spark plasma sintering, and the electrical conductivities of the nanocomposites were evaluated at temperatures ranging from 5 to 300 K. It has been found that the incorporation of MWCNTs converted an insulating silica nanoceramic into metallically conductive composites. The room-temperature conductivities of the nanocomposites, with over 14 orders of magnitude compared with pure silica, are in the range of 8 and 65 S/m. Also, it was interestingly found that the conductivity increased linearly with temperature from 5 to 300 K. 相似文献
108.
High performance liquid chromatographic separation of monoacylglycerol enantiomers as di-3,5-dinitrophenylurethane derivatives
was carried out on a chiral stationary phase, N-(S)-2-(4-chlorophenyl)isovaleroyl-D-phenylglycine chemically bonded tov-aminopropyl silanized silica. Complete separation of the urethane derivatives of racemic monoacylglycerols with saturated
acyl groups of C12−C18 was achieved using a stainless steel column (25 cm long) packed with the 5μ particles, an isocratic elution at ambient temperature
with a mixture of hexane/ethylene dichloride/ethanol as a mobile phase, and a UV detector. Thesn-1 enantiomers were eluted ahead of the correspondingsn-3 enantiomers. Complete separation of thesn-2 isomers from the corresponding enantiomers and partial separation of the enantiomer homologues differing by two acyl carbons
also were observed. 相似文献
109.
110.
In this study, the mechanism of microstructural changes induced by fine particle peening (FPP) treatment was analyzed. Ti–6Al–4V alloy specimens treated with FPP, using tool steel particles with a peening time ranging from 0.1 to 30 s were prepared and examined. Observation of the specimen with short-term FPP treatment revealed that two types of collision dents were formed by the micro abrasive behavior between collided particles and specimen surface. One was the “indented dent,” formed by particles that collided with the surface vertically, and the other was the “ploughed dent,” accompanied by a heap of piled-up material that was ploughed aside during the formation of this dent. Analyses using energy dispersive X-ray spectroscopy (EDS) revealed the presence of particle fragments transferred to the ploughed dents, although no fragments were observed on the indented dents. With an increase in peening time, transferred fragments were embedded into treated materials by deformed material due to a micro ploughing effect. The Fe-rich region became deeper as the particle fragments were embedded. Finally, a lamellar microstructure with a high concentration of Fe was formed by FPP treatment. The effects of micro ploughing during the FPP process on the lamellar modified microstructure formation were clarified. One effect was an enhancement of metal transfer from particles to substrate because virgin metallic surface was exposed; and the other was the mechanical mixing of transferred elements into the substrate. 相似文献