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1.
Upper and lower critical solution temperatures have been determined for solutions of poly(ethylene glycol) in t-butyl acetate and water over the molecular weight range of Mη = 2.18 × 103 to ~1020 × 103. The phase diagram for solutions of poly(ethylene glycol) (Mη = 719 × 103) in t-butyl acetate was expressed as the ‘hour glass’ type, while the phase diagram for solution of poly(ethylene glycol) (Mη = 2.18 × 103 to ~2.29 × 103) in water was expressed as the ‘closed loop’ type. The value of the pressure dependence of the lower critical solution temperature in the poly(ethylene glycol) (Mη = 1020 × 103)/water system over the pressure range of 0 to ~50 atm was negligibly small and positive. 相似文献
2.
Keisuke Ichida Kiyotaka Izumi Keigo Watanabe Nobuhiro Uchida 《Artificial Life and Robotics》2008,12(1-2):258-263
In general, manipulators used for industry and in academic laboratories have actuators to drive each joint. On the other hand,
underactuated manipulators handled by our research have some passive or free joints without actuators and brakes. We recently
developed a switching method of fuzzy energy regions to control such manipulators. In such a method, it is necessary to design
parameters related to energy regions and the gains of some partly stable controllers based on the computed torque method.
Here, the switching method is applied for a three-link underactuated manipulator. We optimize such design parameters related
to fuzzy energy regions by a genetic algorithm. The effectiveness of the present method is illustrated with some simulations.
This work was presented in part at the 12th International Symposium on Artificial Life and Robotics, Oita, Japan, January
25–27, 2007 相似文献
3.
ABSTRACTMedium-Mn steels are energetically investigated as a candidate of the third generation advanced high strength steels (AHSSs). However, their phase transformation and microstructaure evolution during various heat treatments and thermomechanical processing are still unclear. The present study first confirmed the kinetics of static phase transformation behaviour in a 3Mn-0.1C medium-Mn steel. Hot compression tests were also carried out to investigate the influence of high-temperature deformation of austenite on subsequent microstructure evolution. It was found that static ferrite transformation was quite slow in this steel, but ferrite transformation was greatly accelerated by the hot deformation in austenite and ferrite two-phase regions. Characteristic dual-phase microstructures composed of martensite and fine-grained ferrite were obtained, which exhibited superior mechanical properties.This paper is part of a Thematic Issue on Medium Manganese Steels. 相似文献
4.
Nobuhiro Yoshikawa Howon Lee Kojiro Nakagawa Senta Tojo 《Advanced Composite Materials》2016,25(6):61-70
In the curing process of fiber-reinforced plastic accumulators, a thermal spike appears due to the exothermic reaction of the resin. It is necessary to accurately evaluate this thermal spike to guarantee quality and avoid using a trial and error approach to control the temperature. Thus, we developed a curing process simulator that is able to accurately evaluate the thermal spike of the thermosetting resin. A simplified mesoscale finite element model with the definite separation of fiber and resin is used in the simulation. In this study, the newly developed simulation system was examined by comparing its results with the experimental results from the curing process of fiber-reinforced plastic accumulators. 相似文献
5.
Yoshihiko Hangai Hiroaki Yoshida Nobuhiro Yoshikawa 《Metallurgical and Materials Transactions A》2012,43(3):802-805
A new friction powder compaction (FPC) process by the sintering and dissolution process (SDP) route for fabricating open-cell
aluminum (Al) foam, which requires no external heat sources, was developed. Foams with porosities of 74 and 83 pct were successfully
fabricated and their compressive responses were investigated. The sintered mixture during the removal process was observed
nondestructively by X-ray computed tomography (CT) to reveal the progress of the removal of soluble particles and to confirm
that they were completely dissolved. 相似文献
6.
Takuya Honma Ikue Sasaki Nobuhiro Tamura Junichi Tatami Shinichiro Fujichika Katsutoshi Komeya Takeshi Meguro 《International Journal of Applied Ceramic Technology》2013,10(2):348-353
To fabricate functionally graded materials, a highly concentrated slurry of SiO2‐Mo system was prepared and centrifugal force was applied in an attempt to achieve a graded composition. Subsequently, we formed a homogeneous green body with compositional gradation by floc‐casting at 80°C, which was then fired at 1750°C for 10 min in Ar. The sintered body had compositional ratios of SiO2 and Mo as well as electrical conductivities that changed gradually along the direction of centrifugal force. The results demonstrate that centrifugation and control of slurry characteristics such as flocculation are effective in fabricating functionally graded SiO2‐Mo materials. 相似文献
7.
Shu ZhangCheng Lu Nobuhiko TakeichiTetsu Kiyobayashi Nobuhiro Kuriyama 《International Journal of Hydrogen Energy》2011,36(1):634-638
In order to understand the final state of the TiCl3 dopant during the dehydrogenation and rehydrogenation cycles of NaAlH4, we determined the reaction stoichiometry between TiCl3 and NaAlH4 by measuring the amount of hydrogen evolution from NaAlH4 with the varying TiCl3 -load. We found that: (i) TiCl3 reacted with 3 M equivalents of NaAlH4 during the doping process of ball-milling, (ii) the Ti dopant continued to react with NaAlH4 during the first dehydrogenation process until total six equivalents of NaAlH4 were consumed, and (iii) Ti fixed Al, not NaH, so that Al became insufficient during the rehydrogenation process. These findings lead to the conclusion that the reaction stoichiometry between Ti and Al is 1:6, which probably yields TiAl6 and plays a catalytic role in the hydrogen storage reactions of Ti-doped NaAlH4. 相似文献
8.
Fukuyama Y Yasuda N Kim J Murayama H Ohshima T Tanaka Y Kimura S Kamioka H Moritomo Y Toriumi K Tanaka H Kato K Ishikawa T Takata M 《The Review of scientific instruments》2008,79(4):045107
An ultra-high-precision clock system for long time delay has been developed for picosecond time-resolved x-ray diffraction measurements using synchrotron radiation (SR) pulses and synchronized femtosecond laser pulses. The time delay control between pump laser pulse and the probe SR pulse was achieved by combining an in-phase quadrature modulator and a synchronous counter. This method allowed us to change the delay time by a nearly infinite amount while maintaining the precision of +/-8.40 ps. Time-resolved diffraction measurements using the delay control system were demonstrated for precise measurement of an acoustic velocity in a single crystal of gallium arsenide. 相似文献
9.
10.
Shan Liu Jumpei Washio Satoko Sato Yuki Abiko Yuta Shinohara Yuri Kobayashi Haruki Otani Shiori Sasaki Xiaoyi Wang Nobuhiro Takahashi 《International journal of molecular sciences》2022,23(2)
Metformin is a metabolic disruptor, and its efficacy and effects on metabolic profiles under different oxygen and nutrient conditions remain unclear. Therefore, the present study examined the effects of metformin on cell growth, the metabolic activities and consumption of glucose, glutamine, and pyruvate, and the intracellular ratio of nicotinamide adenine dinucleotide (NAD+) and reduced nicotinamide adenine dinucleotide (NADH) under normoxic (21% O2) and hypoxic (1% O2) conditions. The efficacy of metformin with nutrient removal from culture media was also investigated. The results obtained show that the efficacy of metformin was closely associated with cell types and environmental factors. Acute exposure to metformin had no effect on lactate production from glucose, glutamine, or pyruvate, whereas long-term exposure to metformin increased the consumption of glucose and pyruvate and the production of lactate in the culture media of HeLa and HaCaT cells as well as the metabolic activity of glucose. The NAD+/NADH ratio decreased during growth with metformin regardless of its efficacy. Furthermore, the inhibitory effects of metformin were enhanced in all cell lines following the removal of glucose or pyruvate from culture media. Collectively, the present results reveal that metformin efficacy may be regulated by oxygen conditions and nutrient availability, and indicate the potential of the metabolic switch induced by metformin as combinational therapy. 相似文献