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591.
Yoshiaki Morisada Koki Tamashiro Masayoshi Kamai Rintaro Ueji Hidetoshi Fujii 《Welding International》2016,30(8):596-601
Much attention has been paid to FSW as a useful joining process that provides superior characteristics compared with conventional fusion welding. However, the FSW equipment must have a high stiffness due to the applied load and the tool torque, which increases the size of the equipment. Therefore, it is difficult to use the FSW technique on-site for repairs and/or hand-operated welding. In this study, the relationship between the FSW parameters and the process loads was investigated for the FSW with a counterbalanced tool and preheating to evaluate the possible miniaturization of the equipment. The results revealed that the counterbalanced tool concept with preheating was effective for the miniaturization of the equipment because it reduces the applied l and the tool torque during the FSW. Welding direction force Fx and transverse direction force Fy can be reduced below 70 N and 50 N respectively. 相似文献
592.
Kazuhiro Tanaka Md. Nurul Islam Masayoshi Kido Hidetoshi Kita Ken-ichi Okamoto 《Polymer》2006,47(12):4370-4377
Permeability and selectivity of pure gas H2, CO2, O2, N2 and CH4 as well as a mixture of CO2/N2 for sulfonated homopolyimides prepared from 1,4,5,8-naphthalene tetracarboxylic dianhydride (NTDA) and 2,2-bis[4-(4-aminophenoxy)phenyl] hexafluoro propane disulfonic acid (BAPHFDS) were measured and compared to those of the non-sulfonated homopolyimide having the same polymer backbone. The polyimide in a proton form (NTDA-BAPHFDS(H)) displayed higher selectivity of H2 over CH4 without loss of H2 permeability. Strong intermolecular interaction induced by sulfonic acid groups decreased diffusivity of the larger molecules. The CO2/N2 (19/81) mixed gas permeation was investigated as a function of humidity. With increasing relative humidity from 0% RH to 90% RH, the CO2 permeability for NTDA-BAPHFDS(H) polyimide increased by more than one order of magnitude, and the selectivity of CO2/N2 also increased twice or more. On the other hand, the gas permeability for the non-sulfonated polyimide slightly decreased with increasing humidity. NTDA-BAPHFDS(H) polyimide displayed a CO2 permeability of 290×10−10 cm3 (STP) cm/(cm2 s cmHg) and a separation factor of CO2/N2 of 51 at 96% RH, 50 °C and total pressure of 1 atm. 相似文献
593.
Masazumi Tamura Masayoshi Honda Yoshinao Nakagawa Keiichi Tomishige 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2014,89(1):19-33
CO2 has a large effect on global warming by greenhouse gases, and development of an effective technique for the reduction of CO2 is a crucial and urgent issue. From the chemical viewpoint, CO2 is regarded as a stable, safe and abundant C1 resource, and the transformation of CO2 to valuable chemicals is promising not only for reduction of CO2 but also for production of useful chemicals. This mini‐review focuses on the direct conversion of CO2 with diols, aminoalcohols and diamines to cyclic compounds such as cyclic carbonates, cyclic carbamates and cyclic ureas, and in particular discusses the mechanisms for these reactions over heterogeneous catalysts. © 2013 Society of Chemical Industry 相似文献
594.
Yoomin Ahn Takahito Ono Masayoshi Esashi 《Journal of Mechanical Science and Technology》2008,22(2):308-311
Silicon cantilever arrays with a very small pitch for parallel AFM operations were studied. We fabricated 1x104 in eight groups
and 1x30 Si probe arrays and produced a smaller pitch (15 μm) between probe tips by using Si anisotropic etching with a vertical
wall shaped oxide mask. The vertical controls of Si probes were able to operate individually or in a group by integrating
electrostatic actuators into the cantilevers of the probes. The fabricated Si cantilever arrays showed reasonable dynamic
characteristics for the probe cantilever and reliable parallel operation of AFM. 相似文献
595.
Nakadate M Amizuka N Li M Freitas PH Oda K Nomura S Uoshima K Maeda T 《Microscopy research and technique》2008,71(2):93-104
This study aimed to evaluate the histological characteristics of the new bone formed at dental implant placement sites concomitantly grafted with a self-setting tricalcium phosphate cement (BIOPEX-R). Standardized defects were created adjacent to the implants in maxillae of 4-week-old male Wistar rats, and were concomitantly filled with BIOPEX-R. Osteogenesis was examined in two sites of extreme clinical relevance: (1) the BIOPEX-R-grafted surface corresponding to the previous alveolar ridge (alveolar ridge area), and (2) the interface between the grafting material and implants (interface area). At the alveolar ridge area, many tartrate-resistant acid phosphatase (TRAPase)-reactive osteoclasts had accumulated on the BIOPEX-R surface and were shown to migrate toward the implant. After that, alkaline phosphatase (ALPase)-positive osteoblasts deposited new bone matrix, demonstrating their coupling with osteoclasts. On the other hand, the interface area showed several osteoclasts initially invading the narrow gap between the implant and graft material. Again, ALPase-positive osteoblasts were shown to couple with osteoclasts, having deposited new bone matrix after bone resorption. Transmission electron microscopic observations revealed direct contact between the implant and the new bone at the interface area, although few thin cells could still be identified. At both the alveolar ridge and the interface areas, newly formed bone resembled compact bone histologically. Also, concentrations of Ca, P, and Mg were much alike with those of the preexistent cortical bone. In summary, when dental implant placement and grafting with BIOPEX-R are done concomitantly, the result is a new bone that resembles compact bone, an ideal achievement in reconstructive procedures for dental implantology. 相似文献
596.
Hirokatsu Umegami Kazuhiro Umetani Masayoshi Yamamoto Eiji Hiraki 《IEEJ Transactions on Electrical and Electronic Engineering》2015,10(Z1):S168-S170
Electric‐field coupling wireless power transfer has been commonly analyzed using the circuit model. However, the circuit behavior of this model is not necessarily apparent because their resonant modes can be far complicated than the basic LC oscillation. This issue is addressed in this paper by proposing a novel equivalent circuit for a basic wireless power transfer system. This equivalent circuit has a simpler topology than the conventional circuit model. Furthermore, the equivalent circuit allows intuitive understanding of three types of the resonant modes. Along with theoretical derivation of the proposed equivalent circuit, this paper also presents simulation results, which verified the appropriateness of the equivalent circuit. © 2015 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc. 相似文献
597.
Kenji Saito Tsuyoshi Ito Takashi Kuribayashi Kazumi Mochida Teruo Nakakuki Masaru Shibata Masayoshi Sugawara 《Starch - St?rke》2001,53(9):424-430
Resistant starch content of high‐amylose corn starch (HAS) was doubled by heat‐moisture treatment. Resistant starch content of HAS and heat‐moisture treated high‐amylose corn starch (HMT‐HAS) were 31.8 and 67.3%, respectively, as determined by enzymatic‐gravimetric method. Effects of the two types of high‐amylose corn starches, HAS and HMT‐HAS, on starch fermentation, microflora, pH, short chain fatty acid (SCFA) content and β‐glucuronidase activity in the cecal content have been investigated. Rats were given ordinary corn starch (OCS; control), HAS or HMT‐HAS at 10% level for 10 13 days. The cecal and colorectal content s weights were larger in HAS and HMT‐HAS groups than in the OCS group. The cecal content s weight did not differ between HAS and HMT‐HAS groups, while the colorectal content s weight was higher in the HMT‐HAS group than in the HAS group. The upper and lower small intestinal and cecal starch contents were significantly higher in the HAS and HMT‐HAS groups than in the OCS group, whereas there were no differences between colorectal starch content in group OCS and HAS. Starch excretion in feces was significantly higher in groups HAS and HMT‐HAS than in group OCS, the increase in the HMT‐HAS group was especially remarkable. The composition of the cecal microflora was not effected by the diet. β‐Glucuronidase activities in rats fed HAS or HMT‐HAS decreased. SCFA concentration was higher in groups HAS and HMT‐HAS than in group OCS, and the cecal pH was lower in groups HAS and HMT‐HAS than in group OCS. 相似文献
598.
Masato Sasaki Hirokatsu Umegami Masayoshi Yamamoto 《IEEJ Transactions on Electrical and Electronic Engineering》2016,11(Z2):S144-S145
Silicon carbide schottky barrier diodes (SiC SBDs) have much better characteristic than Si PiN diode in high voltage applications because SiC SBDs do not have recovery effect. However, simple replacing is not the most effective way. In a boost converter, the power loss caused by the SiC SBD can be divided into the conduction loss of the SiC SBD and the loss caused by the energy stored in the junction capacitance of the SiC SBD. Therefore analysis of not only the conduction loss but also the loss caused by the energy stored in the junction capacitance of the SiC SBD can realize the SiC SBD selection to improve the efficiency of the boost converter. © 2016 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc. 相似文献
599.
The effect of lubricants on deep drawability was studied for two types of zinc-coated steel sheets on a high-speed deep-drawing machine. The drawability of galvannealed steel sheet, GA, at low speeds is significantly improved by friction modifiers, due to reduction in frictional forces around the die radius. In contrast to the results for GA, double layered steel, GAE, which has an Fe-rich alloy coating on the top, and is superior to GA in terms of drawability, is insensitive to changes in the additives. This is mainly because the hardness of the upper coating layer of GAE decreases frictional resistance through a decline in the boundary contact area. 相似文献