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排序方式: 共有1608条查询结果,搜索用时 801 毫秒
71.
Koji Takahashi Sota Watanabe Yoshio Urabe Masakazu Hisatsune 《Nuclear Engineering and Design》2009,239(12):2719-2727
Low cycle fatigue tests were conducted using 100A elbow specimens made of STPT410 carbon steel with local wall thinning. Local wall thinning by erosion/corrosion was simulated by machined pipe wall thinning. The local wall thinning areas were located at three different areas, called extrados, crown and intrados. The elbow specimens were subjected to cyclic in-plane bending under displacement control without internal pressure. The effects of eroded conditions, such as eroded ratio, eroded angle and position, on the low cycle fatigue behavior and fatigue life were discussed by using experimental results and finite element analyses. Also the location of crack initiation and the crack growth direction could be predicted by three dimensional elasto-plastic finite element analyses. In addition, the safety margin of eroded elbows against seismic loading was discussed by comparing the fictitious stress of elbows with the allowable stress limit demanded by the design code. 相似文献
72.
Takeyuki Gotoh Fuyuki Abe Takenori Ishizu Masaki Yoshio 《Journal of power sources》1996,60(2):193-196
A study of the pyrolysis of an aqueous solution of manganese nitrate in the presence of silver compounds has been carried out. Thermal analysis showed that the MnO2 formation temperature and the transformation temperature from MnO2 to Mn2O3 shifted towards a lower temperature in the presence of silver acetate. A large particle-size and high crystallinity MnO2 was formed; this may be a useful method of making an excellent tantalum capacitor with high capacitance. 相似文献
73.
Using our designed robot, previous work has confirmed that bimanual training induced greater oxygenated-hemoglobin concentration than unilateral-limb training. However, the inter-hemispheric asymmetry of oxygenated-hemoglobin concentration was not compared between the bimanual and unilateral-limb patterns. To confirm the merits of our designed robot based on cerebral hemoglobin activation, 18 healthy subjects performed bimanual and unilateral-limb tasks in active-resisted mode and active-assisted mode for the right and left control sides (determines from that which limb provides a larger force). Analyses of variance were performed to compare the laterality index (LI) of two hemispheres between the two control sides, and to compare oxygenated-hemoglobin concentration between the different training patterns. The difference of LI between the two control sides was distinct in unilateral-limb patterns (p?=?0.029) but not obvious in bimanual patterns. As for the oxygenated-hemoglobin, active-resisted tasks induced a higher concentration than active-assisted tasks in the left control side (p?=?0.048). Results demonstrated that the proposed bimanual training induced the functional integrity of two hemispheres, and the robot is favorable for improving bimanual movement-coordination function. Additionally, active-resisted tasks had a higher difficulty level than active-assisted task. Therefore, the robot has a potential for delivering strength enhancement training in bimanual patterns. 相似文献
74.
75.
Takumi Watanabe Yong He Naoki Asakawa Naoko Yoshie Yoshio Inoue 《Polymer International》2001,50(4):463-468
The specific interactions between several low‐molecular‐weight diamino compounds and poly(ε‐caprolactone) (PCL) have been investigated by FT‐IR. It was found that PCL and 3,3′‐diaminodiphenylmethane (3,3′‐DADPM) interact through strong intermolecular hydrogen bonds in the blend. Thermal and mechanical properties of PCL/3,3′‐DADPM blends were investigated by DSC and tensile measurements, respectively. The glass transition temperature of the blend increases while both the melting point and the elongation‐at‐break of the blend decrease with the increase of 3,3′‐DADPM content. Besides 3,3′‐DADPM, several other low‐molecular‐weight compounds containing two amino groups, such as o‐phenylenediamine or 1,6‐diaminohexane, were also added into PCL and the corresponding blend systems were investigated by FT‐IR and DSC. The effect of the chemical structure of the additives on the properties of PCL is discussed. © 2001 Society of Chemical Industry 相似文献
76.
Effect of Ultrasonication on the Microstructure and Tensile Elongation of Zirconia-Dispersed Alumina Ceramics Prepared by Colloidal Processing 总被引:1,自引:0,他引:1
Tohru S. Suzuki Yoshio Sakka Keishi Nakano Keijiro Hiraga 《Journal of the American Ceramic Society》2001,84(9):2132-2134
To obtain dense, fine-grained ceramics, fine particles and advanced powder processing, such as colloidal processing, are needed. Al2 O3 and ZrO2 particles are dispersed in colloidal suspensions by electrosteric repulsion because of polyelectrolyte absorbed on their surfaces. However, additional redispersion treatment such as ultrasonication is required to obtain dispersed suspensions because fine particles tend to agglomerate. The results demonstrate that ultrasonication is effective in improving particle dispersion in suspensions and producing a homogeneous fine microstructure of sintered materials. Superplastic tensile ductility is improved by ultrasonication in preparing suspensions because of the dense and homogeneous fine microstructure. 相似文献
77.
Tohru S. Suzuki Tetsuo Uchikoshi Yoshio Sakka 《Journal of the European Ceramic Society》2009,29(12):2627-2633
The preparation of oriented AlN bulk ceramics with and without additives was achieved by slip casting in a high magnetic field. The a and b axes of the AlN were aligned parallel to the direction of the magnetic field. The degree of crystallographic orientation was controlled by the viscosity of the slurry and the grain growth during sintering attributed to the sintering additives. The mechanical properties of the textured AlN depended on the direction of the crystallographic orientation. 相似文献
78.
Shixue Wang Yoshio Utaka Yutaka Tasaki 《International Journal of Heat and Mass Transfer》2009,52(19-20):4386-4389
An experiment was carried out to examine heat and mass transfer between constant-temperature water and dry air through a porous plate having extremely small pores. The effects of the thermal conductivity in the porous plate on moisture transport were investigated. The controlling factor for moisture transport was found to be the thermal resistance inside the porous plate having a low-thermal-conductivity and the heat transfer at the surface of the porous plate having a high-thermal-conductivity. 相似文献
79.
80.
Myo Than Htay Yuji Tani Yoshio Hashimoto Kentaro Ito 《Journal of Materials Science: Materials in Electronics》2009,20(Z1):341-345
ZnO nanowires were grown by an ultrasonic spray pyrolysis technique. The aspect ratio and size of the wire were dependent
mainly on the pH value of a precursor solution and the growth temperature. By high-resolution transmission electron microscopic
analysis and photoluminescence measurements, it was confirmed that the nanowires are monocrystalline with good optical quality. 相似文献