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51.
52.
SFLAC (state feedback and load acceleration control) is proposed for vibration suppression and disturbance rejection control of a multi-inertia system. A multi-inertia system is the model of a steel rolling mill, a flexible arm, a large-scale space structure, etc., and its control will be an important problem in the future of motion control. The main idea of SFLAC is to control the load acceleration which can be estimated by the state observer including the disturbance estimation. A simple PI speed controller and SFLAC based on the reduction models using two and three inertia moments are designed. The effectiveness of SFLAC is demonstrated showing some simulation results 相似文献
53.
Hisamoto H Shimizu Y Uchiyama K Tokeshi M Kikutani Y Hibara A Kitamori T 《Analytical chemistry》2003,75(2):350-354
Here we report a design and synthesis of a chemically functional polymer membrane by an interfacial polycondensation reaction and multilayer flow inside a microchannel. Single and parallel dual-membrane structures are successfully prepared by using organic/aqueous two-layer flow and organic/aqueous/organic three-layer flow inside the microchannel followed by an interfacial polycondensation reaction. By using the inner-channel membrane, permeation of ammonia species through the inner-channel membrane is successfully achieved. Furthermore, horseradish peroxidase is immobilized on one side of the membrane surface to integrate the chemical transform function onto the inner-channel membrane. Here substrate permeation through the membrane and subsequent chemical transformation at the membrane surface are realized. The polymer membrane prepared inside the microchannel has an important role in ensuring stable contact of different phases such as gas/liquid or liquid/ liquid and the permeation of chemical species through the membrane. Furthermore, membrane surface modification chemistry allows chemical transformation of permeated chemical species. These methods are expected to lead to development of complicated and sophisticated chemical systems involving membrane permeation and chemical reactions. 相似文献
54.
Hiromi?YoshidaEmail author Kyoko?Matsuda Yuki?Hirakawa Yoshiyuki?Mizushina 《Journal of the American Oil Chemists' Society》2003,80(7):665-674
To clarify the effects of microwave roasting on the distribution of tocopherols and FA of phospholipids within soybeans, whole
soybeans (Glycine max) were treated by microwave and further evaluted as compared to a raw sample. Tocopherol homologs, measured using HPLC, and
phospholipid profiles, quantified with GC, were determined in the seed coat, the embryonic axis, and selections of cotyledons
separated from three cultivars. The tocopherols were predominantly detected in the axis, followed by the cotyledons, and then
very little in the coat. As much as 25% of the individual tocopherols originally present in the coat were lost at 12 min of
roasting, whereas <25% was lost in the cotyledons and the axis after 20 min of roasting. The greatest rate of phospholipid
loss (P<0.05) was observed in PE, followed by PC and PI, and their changing patterns were more pronounced in the coat than in the
cotyledons or the axis. Thus, tocopherol content and phospholipid profiles change with microwave roasting according to tissue. 相似文献
55.
Ryo Toda Yuki Matsushita Mitsunori Hieda Taku Matsushita Nobuo Wada 《Journal of Low Temperature Physics》2007,148(5-6):785-790
We have measured the heat capacity of 3He adsorbed on three-dimensionally connected nanopores, 2.7 nm in diameter, preplated with about 1.3 atomic layers of 4He. At low coverages of 3He, the 3He heat capacity is roughly constant at the measured temperatures between 0.1 and 1 K. Its molar heat capacity is on the order
of the gas constant R, between 1.1R and 1.8R. This suggests a Boltzmann gas state of the adsorbed 3He. At high coverages, the heat capacity is likely approaching linear in T at low temperatures, which suggests a degenerate state at further lower temperatures. 相似文献
56.
Catalin Popa Yuki Okayasu Ken-ichi Katsumata Toshihiro Isobe Nobuhiro Matsushita Akira Nakajima Taisuke Kurata Kiyoshi Okada 《Journal of Materials Science》2013,48(2):941-947
Porous mullite ceramics with unidirectionally oriented pores were prepared by an extrusion method using rayon fibers as the pore formers. Rayon fibers of 8.1, 9.6, 16.8, and 37.6 μm in diameter were used as the pore formers and were kneaded with alumina powder, kaolin clay, China earthen clay, and water to form pastes. These pastes were extruded into cylindrical tubes, dried, and fired at 1500 °C for 4 h. The apparent porosities ranged from 45.7 to 48.2 %. The pore size distributions showed a sharp peak at 9.4, 10.0, 15.6, and 30 μm with increasing fiber diameters. The height of the capillary rise was 1780, 1670, 1320, and 950 mm with increasing fiber diameter. The maximum capillary rise is much higher than previously reported. The contact angle and effective pore radius that determine the capillary rise ability were calculated by fitting the capillary rise curves using the Fries and Dreyer’s equation. 相似文献
57.
Issei Sato Shihori Takeda Yuki Arai Hideharu Miwa Yu Nagase Nobukatsu Nemoto 《Polymer Bulletin》2007,59(5):607-617
Summary Novel poly(tetramethylsilarylenesiloxane) derivatives, i.e. poly(tetramethyl-2,6-silanthrylenesiloxane) (P1), poly(tetramethyl-9,10-silanthrylenesiloxane) (P2), and poly(tetramethyl-1,8-silphenanthrylenesiloxane) (P3), were synthesized by polycondensation of novel disilanol monomers, i.e. 2,6-bis(dimethylhydroxysilyl)-anthracene (M1), 9,10-bis(dimethylhydroxysilyl)anthracene (M2), and 1,8-bis(dimethylhydroxysilyl)phenanthrene (M3), respectively. P1 and P3 were soluble in common organic solvents, such as benzene, toluene, chloroform, dichloromethane, tetrahydrofuran, etc. whereas P2 was almost insoluble in common organic solvents. It was revealed that P1 and P3 were amorphous and that P2 exhibited the crystallinity, as deduced from differential scanning calorimetry (DSC) and X-ray diffraction measurements.
The glass transition temperatures (Tg’s) of P1 (118 °C) and P3 (100 °C) were much higher than that of poly(tetramethyl-1,4-silphenylenesiloxane). The temperature at 5% weight loss (Td5) of P3 was 500 °C, which was higher than those of P1 and P2, and comparable to that of poly(tetramethyl-1,4-silphenylenesiloxane). It would be speculated that the thermostability of
the series of poly(tetramethyl-silarylenesiloxane) derivatives is dependent on the stability of arylene moieties incorporated. 相似文献
58.
A chemical heat-pump system using two hydrogen-absorbing alloys is proposed to utilize heat exhausted from a high-temperature source such as high-temperature-gas-cooled reactor, HTGR, which is designed to produce H2 more efficiently. The overall system proposed here consists of HTGR, He gas turbines, chemical heat pumps and reaction vessels corresponding to the three-step decomposition reactions comprising the I–S process. A fundamental research is performed experimentally on heat generation in a single bed packed with a hydrogen-absorbing alloy that works at the H2 production temperature. The hydrogen-absorbing alloy of Zr(V1−xFex)2 is selected as a material that has a proper plateau pressure for the heat-pump system operated between the input and output temperatures of HTGR. Temperature jump due to heat generated when the alloy absorbs H2 proves that the alloy–H2 system can heat up the exhaust gas even at 600 °C without any external mechanical force. 相似文献
59.
Yuki Totani Atsushi Sugino Toshiki Miyazaki Chikara Ohtsuki 《Materials science & engineering. C, Materials for biological applications》2010,30(4):624-630
Polymethylmethacrylate (PMMA)-based bone cement is widely used for the fixation of artificial joints. However, it is not considered a bioactive material because it lacks the ability to induce a direct bond with bone. In order to improve the long-term stability of cemented fixations, the development of bioactive bone cements is desirable. An essential requirement of a bioactive material includes the induction of bone-like apatite on its surface within the in vivo environment. Previously, we prepared bioactive PMMA-based bone cements by a modification with water-soluble calcium salts and alkoxysilane. Because spatial design may enhance apatite formation on bioactive material surfaces in vivo, we aimed to evaluate the effect of spatial design on apatite formation on modified PMMA-based bone cements in simulated body fluid (SBF). We found that an appropriate spatial design shortened the induction period for the apatite deposition on the modified bone cements. It is expected that osteoconduction would be enhanced in spontaneously created gap between the cement and the host bone leading to tight integration. 相似文献
60.
Pulse generators (PGs) are equipped to detect the rotor frequency of induction traction motors for torque control in railway vehicle traction field. Eliminating PGs is preferable from the viewpoints of increasing the reliability of the traction system, reduction of both the initial and maintenance cost, and downsizing induction traction motors. Expecting those advantages, we have been studying the application of a sensorless control method to induction traction motor control. Prior to some reports of studies and tests to apply speed sensorless strategy to railway vehicle traction we launched ideas to apply the speed sensorless control strategy and results of the studies and tests. In this paper, we present the novel control method for railway vehicle traction and some results of theoretical study and tests. © 2007 Wiley Periodicals, Inc. Electr Eng Jpn, 161(2): 69–77, 2007; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.20273 相似文献