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961.
Dr. Kosuke Ino Dr. Yusuke Kanno Dr. Kumi Y. Inoue Dr. Atsushi Suda Ryota Kunikata Masahki Matsudaira Prof. Dr. Hitoshi Shiku Prof. Dr. Tomokazu Matsue 《Angewandte Chemie (International ed. in English)》2017,56(24):6818-6822
Motion tracking of microorganisms is useful to investigate the effects of chemical or physical stimulation on their biological functions. Herein, we describe a novel electrochemical imaging method for motion tracking of microorganisms using a large-scale integration (LSI)-based amperometric device. The device consists of 400 electrochemical sensors with a pitch of 250 μm. A convection flow caused by the motion of microorganisms supplies redox species to the sensors and increases their electrochemical responses. Thus, the flow is converted to electrochemical signals, enabling the electrochemical motion tracking of the microorganisms. As a proof of concept, capillary vibration was monitored. Finally, the method was applied to monitoring the motion of Daphnia magna. The motions of these microorganisms were clearly tracked based on the electrochemical oxidation of [Fe(CN)6]4− and reduction of O2. 相似文献
962.
A mesoscopic tiling pattern with 12-fold symmetry has been observed in a three-component polymer system composed of polyisoprene, polystyrene, and poly(2-vinylpyridine) which forms a star-shaped terpolymer, and a polystyrene homopolymer blend. Transmission electron microscopy images reveal a nonperiodic tiling pattern covered with equilateral triangles and squares, their triangle/square number ratio of 2.3 (approximately equal to 4/sqrt[3]), and a microbeam x-ray diffraction pattern shows dodecagonal symmetry. The same kind of quasicrystalline structures have been found for metal alloys (approximately 0.5 nm), chalcogenides (approximately 2 nm), and liquid crystals (approximately 10 nm). The present result (approximately 50 nm) confirms the universal nature of dodecagonal quasicrystals over several hierarchical length scales. 相似文献
963.
964.
965.
Surface and subsurface oxygen vacancies on the slightly reduced CeO(2)(111) surface have been studied by atomic resolution dynamic force microscopy at 80 K. Both types of defect are clearly identified by the comparison of the observed topographic features with the corresponding structures predicted from recent first-principles calculations. By combining two simultaneously acquired signals (the topography and the energy dissipated from the cantilever oscillation), we are able to unambiguously locate subsurface oxygen vacancies buried at the third surface atomic layer. We report evidence of local ordering of these subsurface defects that suggests the existence of a delicate balance between subtle interactions among adjacent subsurface oxygen vacancy structures. 相似文献
966.
Development of a neutron generating target for compact neutron sources using low energy proton beams
967.
Mesoporous Zirconium Phenylenesiliconate‐phosphonate Hybrids with Ordered Lamellar Nanostructures 下载免费PDF全文
Prof. Dr. Kazuyuki Maeda Hiroki Kobayashi Kaku Oguro Masato Otsu Dr. Atsushi Kondo Dr. Tei Maki 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(47):17091-17099
Novel ordered lamellar mesostructure pZrPS‐2 was hydrothermally prepared by using zirconium propoxide and 4‐(EtO)2OPC6H4Si(OEt)3 (pPPS‐E), which was hydrolyzed to organic building units substituted with both siliconate and phosphonate groups, in the presence of CnTAB and TMAOH. The pZrPS‐2 materials were obtained at a Zr/PPS ratio of 2 or higher and the basal spacing was increased by using a longer‐chain surfactant (n=12–18). Removal of the occluded surfactants at 300 °C resulted in retention of the lamellar structure with negligible shrinkage of the interlayer distance. Nitrogen adsorption studies revealed the ordered mesoporous nature of pZrPS‐2 with a pore diameter of approximately 2 to 3 nm. The lamellar structure is assumed to be composed of layers that include zirconia‐based crystalline nanodomains and interlayer pillars mainly based on PPS units. Although lamellar structures with the same crystalline phase also formed when no surfactant was added or when the meta isomer of PPS was used, no mesoporous materials were obtained except pZrPS‐2. A possible schematic model to elucidate these results is also proposed. 相似文献
968.
Cover Picture: Ruthenium‐Immobilized Periodic Mesoporous Organosilica: Synthesis,Characterization, and Catalytic Application for Selective Oxidation of Alkanes (Chem. Eur. J. 44/2015) 下载免费PDF全文
969.
Akihiro Sasoh Tatsuya Harasaki Takuya Kitamura Daisuke Takagi Shigeyoshi Ito Atsushi Matsuda Kouji Nagata Yasuhiko Sakai 《Shock Waves》2014,24(5):489-500
When a shock wave ejected from the exit of a 5.4-mm inner diameter, stainless steel tube propagated through grid turbulence across a distance of 215 mm, which is 5–15 times larger than its integral length scale \(L_{u}\) , and was normally incident onto a flat surface; the peak value of post-shock overpressure, \(\Delta P_{\mathrm{peak}}\) , at a shock Mach number of 1.0009 on the flat surface experienced a standard deviation of up to about 9 % of its ensemble average. This value was more than 40 times larger than the dynamic pressure fluctuation corresponding to the maximum value of the root-mean-square velocity fluctuation, \(u^{\prime }= 1.2~\hbox {m}/\hbox {s}\) . By varying \(u^{\prime }\) and \(L_{u}\) , the statistical behavior of \(\Delta P_{\mathrm{peak}}\) was obtained after at least 500 runs were performed for each condition. The standard deviation of \(\Delta P_{\mathrm{peak}}\) due to the turbulence was almost proportional to \(u^{{\prime }}\) . Although the overpressure modulations at two points 200 mm apart were independent of each other, we observed a weak positive correlation between the peak overpressure difference and the relative arrival time difference. 相似文献
970.
Matsuoka S Ota Y Washio A Katada A Ichioka K Takagi K Suzuki M 《Organic letters》2011,13(14):3722-3725
Highly selective tail-to-tail dimerization of methyl methacrylate has been realized by an N-heterocyclic carbene catalyst, giving dimethyl 2,5-dimethyl-2-hexenedioate with an E/Z ratio of 95:5 in 86% isolated yield. The umpolung mechanism is proposed on the basis of interception of the intermediates using ESI-MS analyses and deuterium-labeling experiments. 相似文献