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61.
Takuma Uchiyama Hidetsugu Terada Hironori Mitsuya 《Journal of Mechanical Science and Technology》2010,24(1):47-50
Using the 5-degree of freedom parallel-serial hybrid robot, to realize the de-burring, new forward and inverse kinematic calculation
methods based on the “off-line teaching” method are proposed. This hybrid robot consists of a parallel stage section and a
serial stage section. Considering this point, each section is calculated individually. And the continuous path control algorithm
of this hybrid robot is proposed. To verify the usefulness, a prototype robot is tested which is controlled based on the proposed
methods. This verification includes a positioning test and a pose test. The positioning test evaluates the continuous path
of the tool center point. The pose test evaluates the pose on the tool center point. As the result, it is confirmed that this
hybrid robot moves correctly using the proposed methods. 相似文献
62.
Hiroyuki Hirakata Naomichi Fukuhara Shoichi Ajioka Akio Yonezu Masayuki Sakihara Kohji Minoshima 《Acta Materialia》2012,60(11):4438-4447
To clarify the effects of film thickness on the creep properties of nano-films we conducted tensile creep experiments on freestanding aluminum films with thickness values in the range ~100–800 nm at room temperature. The nano-films showed typical creep behavior comprising transient, steady-state, and accelerated creep stages. The steady-state creep exponents of the 100–800 nm thick specimens were 0.84–2.7 in the stress range 30–120 MPa, which are close to the value for diffusion creep (1). Creep deformation clearly shows a thickness effect: the steady-state creep rate increases as the thickness decreases from 800 to 400 nm, shows a peak in the range 400–200 nm, and then decreases in the 200–100 nm thickness range. The creep experiments under a small stress of 1 MPa show a negative strain rate, indicating the presence of a driving force to reduce the surface area due to surface tension. The explanation for the thickness effect is as follows. Since the ratio of surface and grain boundary area to volume increases with decreasing thickness, diffusion creep along these paths is enhanced, resulting in an increase in the creep rate. As the thickness decreases to 200–100 nm, however, the surface tension effect to reduce the surface area becomes dominant, decreasing the creep rate. In addition, the creep rate of the nano-films is about two or three orders of magnitude smaller than that of the bulk material dominated by the dislocation creep mechanism. 相似文献
63.
Masahiro Shikano Hironori KobayashiShinji Koike Hikari SakaebeYoshiyasu Saito Hironobu HoriHiroyuki Kageyama Kuniaki Tatsumi 《Journal of power sources》2011,196(16):6881-6883
18650-type cylindrical cells using LiNi1/3Mn1/3Co1/3O2 (NMC) and hard carbon as positive and negative electrode material, respectively, were fabricated and degraded by cycle tests. The capacity of the cells remained more than 95% and 85% after cycle tests at 25 and 50 °C, respectively. After the cycle tests, Li-deficient cubic phase was observed on the surface of NMC. This phenomenon should be related to the degradation mechanism of this type of cell. 相似文献
64.
Ultrathin metallic wires having defects may show much lower strength compared to the strength of the wire material. To characterize ultrathin Pt wires having the nominal diameter of 625 nm, tensile test of the wires was performed by developing a testing platform and a gripping technology. Fracture stress determined by the tensile test showed much higher value compared with that of bulk Pt. However, the fracture stress of some of the wires was lower than the yield stress of the wire determined by the bending test. From the observation of the fracture surfaces, it was found that the lower fracture stress of the wires was due to the defects in the wires and such wires showed brittle fracture behavior. 相似文献
65.
An inhibitor of human tyrosinase activity in rum distillate wastewater was isolated and identified as (S)-(+)-imperanene (1). (S)-(+)-Imperanene significantly inhibited tyrosinase isolated from HMV-II cells (IC(50) 1.85 mM). Inhibition kinetics studies revealed that imperanene is a competitive inhibitor of tyrosinase when L-3,4-dihydroxyphenylalanine is used as the substrate. The inhibitory activities of 1, O-beta-D-glucopyranosyl imperanene (2) and O-beta-D-glucopyranosyl-3-methoxyl imperanene (3) were 1>2>3. 相似文献
66.
CNT-PyC-SiC/SiC double-layer coatings were prepared by growth of CNTs on C/C followed by pyrolytic carbon deposition and SiC deposition. The microstructure and the oxidation behavior of the coatings were investigated. With increasing PyC amount in the coating, the coating showed fewer cracks and a higher oxidation resistance and thermal shock resistance. CNT-PyC played a role in improving the bonding strength between C/C and coatings, alleviating stress in SiC coating and decreasing the cracks. 相似文献
67.
Koichiro Oishi Genki Saito Kiyoshi Ebina Masanori Nagahashi Kazuo Jimbo Win Shwe Maw Hironori Katagiri Makoto Yamazaki Hideaki Araki Akiko Takeuchi 《Thin solid films》2008,517(4):1449-1452
Cu2ZnSnS4 films were grown on Si (100) by vacuum evaporation using elemental Cu, Sn, S and binary ZnS as sources. X-ray diffraction patterns of films grown at different substrate temperatures indicated that polycrystalline growth was suppressed and the orientational growths were relatively induced in a film grown at higher temperatures. Tetragonal structure of Cu2ZnSnS4 films was confirmed by studying RHEED patterns. The existence of c-axis ([001] direction) growth, two kinds of a-axis (〈100〉 direction) growth and four kinds of {112} twins which can be classified as two symmetrical pairs is proposed. Broad emissions at around 1.45 eV and 1.31 eV were observed in the photoluminescence spectrum measured at 13 K. 相似文献
68.
T Takahashi H Suzuki T Inuzuka H Shibata M Maki 《International journal of molecular sciences》2012,13(6):7532-7549
ALG-2 is a penta-EF-hand Ca(2+)-binding protein and interacts with a variety of intracellular proteins. Two types of ALG-2-binding motifs have been determined: type 1, PXYPXnYP (X, variable; n = 4), in ALIX and PLSCR3; type 2, PXPGF, in Sec31A and PLSCR3. The previously solved X-ray crystal structure of the complex between ALG-2 and an ALIX peptide containing type 1 motif showed that the peptide binds to Pocket 1 and Pocket 2. Co-crystallization of ALG-2 and type 2 motif-containing peptides has not been successful. To gain insights into the molecular basis of type 2 motif recognition, we searched for a new hydrophobic cavity by computational algorithms using MetaPocket 2.0 based on 3D structures of ALG-2. The predicted hydrophobic pocket designated Pocket 3 fits with N-acetyl-ProAlaProGlyPhe-amide, a virtual penta-peptide derived from one of the two types of ALG-2-binding sites in PLSCR3 (type 2 motif), using the molecular docking software AutoDock Vina. We investigated effects of amino acid substitutions of the predicted binding sites on binding abilities by pulldown assays using glutathione-S-transferase -fused ALG-2 of wild-type and mutant proteins and lysates of cells expressing green fluorescent protein -fused PLSCR3 of wild-type and mutants. Substitution of either L52 with Ala or F148 with Ser of ALG-2 caused loss of binding abilities to PLSCR3 lacking type 1 motif but retained those to PLSCR3 lacking type 2 motif, strongly supporting the hypothesis that Pocket 3 is the binding site for type 2 motif. 相似文献
69.
70.
Alev Aydıner Bakiye Çakır Hironori Seki Mehmet Başoğlu Atikorn Wongsatanawarid Masato Murakami Ekrem Yanmaz 《Journal of Superconductivity and Novel Magnetism》2011,24(5):1397-1401
In this study, two kinds of melt-processed YBCO samples (Y1050-1 and Y1050-2) grown on a buffer layer of Y2O3 addition were fabricated. The compacted powders were located on a crucible with Y2O3 powder freely poured and a buffer layer of pressed Y2O3 to avoid liquid to spread on the furnace plate. The superconducting transition temperature was determined by a standard four-point
method at temperatures between 40 and 100 K. The transition temperatures of Y1050-1 and Y1050-2 were found to be 91.6 and
92.9 K at zero magnetic fields, respectively. The magnetization measurements were performed using a vibrating sample magnetometer
(VSM) on the same system at 5, 40, and 77 K. The critical current densities for Y1050-1 and Y1050-2 samples were determined
to be 6.5×103 and 5.6×103 A/cm2 at 77 K in zero magnetic fields, respectively. The trapped magnetic field measurements of the samples were performed by using
a Hall probe scanning device and a Fe–Nd–B permanent magnet at 77 K. It was found that the trapped magnetic field of the Y1050-1
sample is higher than that of the Y1050-2 sample. 相似文献