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61.
Satoshi Ogawa Yutaka Masutomi Naomichi Furukawa Tomoki Erata 《Heteroatom Chemistry》1992,3(4):423-429
Diaryl tellurides undergo rapid ligand exchange and disproportionation reactions on treatment with phenyllithium at −78°C. Triarylteliuranes [10-Te-3(C3)]− Li+ were identified as discrete intermediates during the reactions by 125Te, 1H, 13C, and CH-COSY NMR studies. 相似文献
62.
Jun Yano Akihiko Muta Yutaka Harima Akira Kitani 《Journal of Solid State Electrochemistry》2011,15(3):601-605
A poly(2,5-dimethoxyaniline) (PDMA) film was coated on the iron surface by the electropolymerization of 2,5-dimethoxyaniline in neutral buffer solution (pH?6.86). The PDMA film strongly adhered to the surface because of the polar methoxy groups of the PDMA molecules. The fact that no electrochemical response of the PDMA film-coated iron electrode to dissolved Fe2+ exhibited that the PDMA film was less permeable to dissolved species, acting as a diffusion barrier against agents causing corrosion such as H2O and O2. The PDMA film coating greatly lowered the anodic current peak ascribed to the anodic dissolution of iron and the corrosion current in strongly acidic medium, 0.5?M H2SO4 aqueous solution (1?M?????mol?dm??) as well as neutral medium (pH?6.86). The high anti-corrosion ability was due to a hybrid effect of the PDMA film not only as the diffusion barrier, but also as an in situ oxidant in spite of the slight redox activity of PDMA. In addition, the PDMA film is much more durable and adhesive than polyaniline film against over-oxidation. 相似文献
63.
Ichiro Tsuda Hiroshi Watanabe Hiromichi Tsukada Yutaka Yamaguti 《Entropy (Basel, Switzerland)》2022,24(2)
The focus of this article is the self-organization of neural systems under constraints. In 2016, we proposed a theory for self-organization with constraints to clarify the neural mechanism of functional differentiation. As a typical application of the theory, we developed evolutionary reservoir computers that exhibit functional differentiation of neurons. Regarding the self-organized structure of neural systems, Warren McCulloch described the neural networks of the brain as being “heterarchical”, rather than hierarchical, in structure. Unlike the fixed boundary conditions in conventional self-organization theory, where stationary phenomena are the target for study, the neural networks of the brain change their functional structure via synaptic learning and neural differentiation to exhibit specific functions, thereby adapting to nonstationary environmental changes. Thus, the neural network structure is altered dynamically among possible network structures. We refer to such changes as a dynamic heterarchy. Through the dynamic changes of the network structure under constraints, such as physical, chemical, and informational factors, which act on the whole system, neural systems realize functional differentiation or functional parcellation. Based on the computation results of our model for functional differentiation, we propose hypotheses on the neuronal mechanism of functional differentiation. Finally, using the Kolmogorov–Arnold–Sprecher superposition theorem, which can be realized by a layered deep neural network, we propose a possible scenario of functional (including cell) differentiation. 相似文献
64.
Shigeki Yonezawa Yuji Muraoka Yutaka Ueda Zenji Hiroi 《Solid State Communications》2004,129(4):245-248
Effects of epitaxial stress on the metal-insulator transition of V2O3 have been studied for in the form of epitaxial thin films grown on α-Al2O3 (0001) and LiTaO3 (0001) substrates. A metallic phase is stabilized down to 2 K in the V2O3 thin film on α-Al2O3 (0001), where the a-axis is compressed by 4% owing to large epitaxial stress. On the other hand, the transition temperature TMI is raised by 20 K from the value of 170 K in bulk samples in the film on LiTaO3 (0001), where the a-axis is expanded. These results suggest an intimate relationship between the a-axis length and TMI in V2O3. The conductivity of the metallic ultrathin films shows logarithmic temperature dependence below 20 K, probably due to the Anderson localization in two-dimensional systems. 相似文献
65.
66.
Kaisei Matsumoto Kazuki Ueno Prof. Dr. Jun Hirotani Prof. Dr. Yutaka Ohno Prof. Dr. Haruka Omachi 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(28):6118-6121
Owing to their remarkable properties, single-walled carbon nanotube thin-film transistors (SWCNT-TFTs) are expected to be used in various flexible electronics applications. To fabricate SWCNT channel layers for TFTs, solution-based film formation on a self-assembled monolayer (SAM) covered with amino groups is commonly used. However, this method uses highly oxidized surfaces, which is not suitable for flexible polymeric substrates. In this work, a solution-based SWCNT film fabrication using methoxycarbonyl polyallylamine (Moc-PAA) is reported. The NH2-terminated surface of the cross-linked Moc-PAA layer enables the formation of highly dense and uniform SWCNT networks on both rigid and flexible substrates. TFTs that use the fabricated SWCNT thin film exhibited excellent performance with small variations. The presented simple method to access SWCNT thin film accelerates the realization of flexible nanoelectronics. 相似文献
67.
68.
We calculate one-loop contributions to the Kähler potential in 4D effective theory of 5D gauged supergravity (SUGRA) on S1/Z2 with a generic form of the prepotential and arbitrary boundary terms. Our result is applicable to a wide class of 5D SUGRA models. The derivation is systematically performed by means of an N=1 superfield formalism based on the superconformal formulation of 5D SUGRA. As an illustrative example, we provide an explicit expression of the Kähler potential in the case of 5D flat spacetime. 相似文献
69.
Mikiyasu Shirai Matthew Beard James T. Pearson Takashi Sonobe Hirotsugu Tsuchimochi Yutaka Fujii Emily Gray Keiji Umetani Daryl O. Schwenke 《Journal of synchrotron radiation》2013,20(3):441-448
Synchrotron radiation microangiography is a powerful tool for assessing adverse changes in pulmonary vessel density associated with primary pulmonary hypertension (PH). Congestive heart failure (CHF) leads to a `secondary' onset of PH, yet it is unknown whether secondary PH is also associated with reduced vessel density. This study utilized synchrotron radiation to assess both pulmonary vessel density and endothelial function in a Dahl rat model of CHF with secondary PH. High salt‐fed Dahl salt‐sensitive (Dahl‐S) and salt‐resistant (Dahl‐R) rats were anesthetized and microangiography was performed to assess the pulmonary vessel density and vascular responses to (i) sodium nitroprusside (5.0 µg kg?1 min?1), (ii) acetylcholine (3.0 µg kg?1 min?1) and (iii) ET‐1A receptor blockade, BQ‐123 (1 mg kg?1). Dahl‐S rats developed CHF and secondary PH as evident by endothelial dysfunction, impaired vasodilatory responses to acetylcholine, enhanced vasodilatory responses to BQ‐123 and extensive pulmonary vascular remodeling. Consequently, the pulmonary vessel density was adversely reduced. Interestingly, the etiology of secondary PH manifests with structural and functional changes that are comparable with that previously reported for primary PH. One important discrepancy, however, is that ET‐1 modulation of pulmonary vessels is most striking in vessels with a diameter range of 100–200 µm in secondary PH, in contrast to a range of 200–300 µm in primary PH. Such discrepancies should be considered in future studies investigating primary and secondary forms of PH. 相似文献
70.
Yasuhiro Masuda Koichiro Asahi Kichiji Hatanaka Sun-Chan Jeong Shinsuke Kawasaki Ryohei Matsumiya Kensaku Matsuta Mototsugu Mihara Yutaka Watanabe 《Physics letters. A》2012
A neutron EDM measurement with a comagnetometer is discussed. For magnetometry, polarized xenon atoms are injected into a cylindrical cell where a cylindrically symmetric magnetic field and an electric field are applied for the EDM measurement. The geometric phase effect (GPE), which originates from particle motion in a magnetic field gradient, is analyzed in terms of the Dyson series. The motion of the xenon atom is largely suppressed because of a small mean free path. The field gradient is controlled by means of NMR measurements, where the false effect of Earth?s rotation is removed. As a result, the GPE is reduced below 10−28e cm. 相似文献