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Masato Mitani Shogo Yamane Masafumi Yoshio Masahiro Funahashi 《Molecular Crystals and Liquid Crystals》2014,594(1):112-121
5,5′-Bis(2-phenylethynyl)-2,2′-bithiophene derivative 1 containing dendritic moieties linked through amide groups was synthesized. Compound 1 exhibits a rectangular columnar phase on slow cooling from the isotropic liquid. In contrast, a cubic phase is formed as a metastable liquid-crystalline phase by rapid cooling of the isotropic melt. Mechanical shearing induces a cubic–columnar phase transition, accompanied by the change of a photoluminescent color from yellow-green to green. The infrared spectra of 1 suggest that the mechanical stimuli can induce the partial dissociation of the hydrogen bond. This may lead to more disordering of the π-stacks of chromophores. 相似文献
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Ogino M Nakada Y Negoro N Itokawa S Nishimura S Sanada T Satomi T Kita S Kubo K Marui S 《Chemical & pharmaceutical bulletin》2011,59(11):1369-1375
As a part of our research for novel potent and orally available acyl-CoA: cholesterol acyltransferase (ACAT) inhibitors that can be used as anti-atherosclerotic agents, we recently reported the discovery of the (4-phenylcoumarine)acetanilide derivative 1. However, compound 1 showed adrenal toxicity in animal models. In order to search for safer ACAT inhibitors that do not have adrenal toxicity, we examined the inhibitory activity of ACAT in human macrophage and adrenal cells. The introduction of a carboxylic acid moiety on the pendant phenyl ring and the adjustment of the lipophilicity led to the discovery of (2E)-3-[7-chloro-3-[2-[[4-fluoro-2-(trifluoromethyl)phenyl]amino]-2-oxoethyl]-6-methyl-2-oxo-2H-chromen-4-yl]phenyl]acrylic acid (21e), which showed potent ACAT inhibitory activity in macrophages and a selectivity of around 30-fold over adrenal cells. In addition, compound 21e showed high adrenal safety in guinea pigs. 相似文献
96.
Kakue T Yonesaka R Tahara T Awatsuji Y Nishio K Ura S Kubota T Matoba O 《Optics letters》2011,36(21):4131-4133
Parallel phase-shifting digital holography can obtain three-dimensional information of a dynamically moving object with high accuracy by using space-division multiplexing of multiple holograms required for phase-shifting interferometry. We demonstrated high-speed parallel phase-shifting digital holography and obtained images of the phase variation of air caused by a compressed gas flow sprayed from a nozzle. In particular, we found the interesting phenomenon of periodic phase distributions. Reconstructed images were obtained at frame rates of 20,000 and 180,000 frames per second. 相似文献
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Hideyuki Nakanishi Yuto Kawabata Shogo Tsujiai Hayato Tanaka Satoshi Teraji Gbor Holl Istvn Lagzi Tomohisa Norisuye Qui Tran‐Cong‐Miyata 《Angewandte Chemie (International ed. in English)》2020,59(31):13086-13092
The development of methods to pattern nanocrystals with different sizes and shapes remains a challenge. In this study, we demonstrate a unique class of bottom‐up approaches to assemble nanocrystals into patterns. Our approach for patterning nanocrystals focuses on the utilization and control of the chemical reaction of solvents surrounding nanocrystals. The photopolymerization of solvent molecules through a photomask creates time‐dependent concentration gradients of the solvents. Dispersed nanocrystals such as silver nanowires (AgNWs) migrate and are gradually organized and integrated into the polymerizing films based on the concentration gradients. The AgNW‐embedded film properties are determined by the organized AgNW structures and include light transmission and electrical conductivity. Overall, the demonstrated method is very simple, widely applicable to various nanocrystals and solvents, and can thus contribute to the development of a new class of nanocrystal patterning methods. 相似文献
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Optical Review - A waveguide grating on a transparent substrate can serve as an optical notch filter owing to guided-mode resonance. The filtering wavelength is highly sensitive to an incidence... 相似文献
99.
Vladimir Ya. Lee Shogo Miyazaki Hiroyuki Yasuda Akira Sekiguchi 《Phosphorus, sulfur, and silicon and the related elements》2013,188(6):1346-1350
The reaction of trisilirene 1 with propylene sulfide or elemental sulfur produced Si3S-bicyclo[1.1.0]butane 2, which underwent Si–Si insertion of a second S atom forming Si3S2-bicyclo[1.1.1]pentane 3. Analogous reactions of 1 with elemental Se or Te resulted in the formation of heavier analogues of 2, namely, Si3Se-bicyclo[1.1.0]butane 4 and Si3Te-bicyclo[1.1.0]butane 5. Supplemental materials are available for this article. Go to the publisher's online edition of Phosphorus, Sulfur, and Silicon and the Related Elements to view the free supplemental file. GRAPHICAL ABSTRACT 相似文献
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Abstract It is observed that sodium phosphate polymers, in which some of the Na+ ions have been replaced by La3+ ions, are subject to both simple molecular flow and to bond interchange in the glass transition region. These two relaxation mechanisms are separated, and their relative contributions to the shear viscosity are calculated. It is shown that the bond-interchange mechanism is subject to an activation energy of ca. 50 kcal, while that of the molecular flow is of the order of 200 kcal at Tg + 30°C;the latter is of the WLF form. It is further shown that the La3+ ions act as cross-links, at least at low concentrations, and that bond interchange occurs at the site of the La3+ ions rather than at random along the polymer chain. 相似文献