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91.
Yutaka Ohsedo Ichiro Imae Yasuhiko Shirota 《Journal of Polymer Science.Polymer Physics》2003,41(21):2471-2484
A new family of methacrylate polymers containing pendant terthiophene, quaterthiophene, quinquethiophene, and sexithiophene was synthesized by the radical polymerization of the corresponding methacrylate monomers, and the electrochemical and electrochromic properties were investigated. The anodic oxidation of these polymers in the presence of tetra‐n‐butylammonium perchlorate as a supporting electrolyte produced radical‐cation salts of pendant oligothiophenes with ClO as a dopant. The electrochemically oxidized polymers had partially crosslinked structures resulting from the coupling reaction of pendant oligothiophene radical cations, the extent of crosslinking significantly decreasing with the increasing conjugation length of the pendant oligothiophenes. Comparative spectroelectrochemical studies of the monomers in solution and the polymers as solid films showed that π‐dimer formation of oligothiophene radical cations took place more readily for the polymer films than for the monomers in solution. This new family of methacrylate polymers containing pendant oligothiophenes constitutes a new class of potential electrochromic materials, undergoing reversible, clear color changes on electrochemical oxidation and reduction. © 2003 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 41: 2471–2484, 2003 相似文献
92.
Masaaki Sakakura Yuki Ishiguro Yasuhiko Shimotsuma Naoaki Fukuda Kiyotaka Miura 《Applied Physics A: Materials Science & Processing》2014,114(1):261-265
After the photoexcitation by a femtosecond laser pulse inside a LiF single crystal, four cracks appear in the <110> directions of the crystal from the photoexcited region. In our previous study, we found that a femtosecond laser-induced stress wave is responsible for generation and elongation of cracks inside a LiF single crystal. This finding suggests that we can control laser-induced cracks by modulating laser-induced stress waves. In this study, we applied parallel fs laser irradiation with a spatial light modulator to generate multiple stress waves at the same time, and found the modulation of crack formation; one crack became thinner and shorter than any other cracks. By a pump-probe imaging of dynamics of crack generation, we showed that the constructive interference of stress waves at a crack tip could compress the crack, which results in a thinner and shorter crack. 相似文献
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94.
Leo Esaki Masatoshi Kitamura Satoshi Iwamoto Yasuhiko Arakawa 《Proceedings of the Japan Academy. Series B, Physical and biological sciences》2010,86(4):451-453
We report, as the result of shelf-life tests for Esaki diodes, the observation of minute but tangible reductions in the tunnel current after the lapse of half a century. The reduction could be attributed to 0.25% widening in the tunnel path. 相似文献
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With the aim of developing new oligothiophene-based liquid crystals involving hydrogen bonding, new terthiophene derivatives containing an alkylamide group, N,N'-distearyl-2,2' : 5',2"-terthiophene-5,5"-dicarboxamide (DNC183T) and N,N'-dialkyl-5,5"-dibromo-2,2' : 5',2"-terthiophene-4,4"-dicarboxamides (DNCnDBr3T, n = 5, 8, 16, 18), were designed and synthesized, and their thermal behaviour examined. While DNC183T did not exhibit liquid crystallinity, DNCnDBr3T compounds with n = 8, 16, 18 were found to form smectic A phases. In addition to liquid crystal behaviour, crystal polymorphism was also observed for DNC16DBr3T. It is shown that both the position of the amido group and the alkyl chain length greatly affect liquid crystal phase formation. The absence of liquid crystallinity in the corresponding ester derivatives suggests that intermolecular hydrogen bonding also plays a role in the formation of liquid crystal phases in the DNCnDBr3T system. 相似文献
98.
Masahiro Kikuchi Mohammad S. Hussain Norio Morishita Mitsuko Ukai Yasuhiko Kobayashi Yuhei Shimoyama 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2010,75(1):310-313
An electron spin resonance (ESR) spectroscopic study of radicals induced in irradiated fresh mangoes was performed. Mangoes in the fresh state were irradiated with γ-rays, lyophilized and then crushed into a powder. The ESR spectrum of the powder showed a strong main peak at g = 2.004 and a pair of peaks centered at the main peak. The main peak was detected from both flesh and skin specimens. This peak height gradually decreased during storage following irradiation. On the other hand, the side peaks showed a well-defined dose–response relationship even at 9 days post-irradiation. The side peaks therefore provide a useful means to define the irradiation of fresh mangoes. 相似文献
99.
Yoji Imai Yasuhiko Takahashi Toshiya Kumagai 《Journal of magnetism and magnetic materials》2010,322(18):2665-43
Geometrical optimization of tetra-3d metal nitrides (Mn4N, Fe4N, Co4N, and Ni4N) has been performed and the relations of their energies (E) and their total magnetic moments (M) are obtained by plane-wave-basis density-functional calculations without any assumption of specific spin arrangement. The E vs. M relations obtained for Fe4N and Mn4N have a bimodal character. The ground state of Fe4N is a high-spin state, which would correspond to the ferromagnetic character, while that of Mn4N is a low-spin state, which would correspond to the observed ferrimagnetic character. Lattice constants and total magnetic moments of these tetra-3d metal nitrides are almost accurately predicted. From the spin-polarized densities of states curves, Co4N would have the largest spin polarization ratio of 0.88, which suggests Co4N can be a candidate material for ferromagnetic electrodes for spin-injection. 相似文献
100.
We investigated simultaneous determination of haloperidol (HAL), its three metabolites [reduced HAL (R-HAL), 3-(4-fluorobenzoyl)propionic acid (FBPA) and 4-(4-chlorophenyl)-4-hydroxypiperidine (CPHP)] and two related compounds [spiperone (SPI) and droperidol (DRO)] in phosphate-buffered saline using high-performance liquid chromatography (HPLC) coupled with dual ultraviolet detection (220 and 250 nm). Retention times of HAL, R-HAL, FBPA, CPHP, SPI and DRO were 16.8, 11.8, 10.2, 4.1, 12.6 and 8.3 min, respectively. Their lower limits of detection were 7.5, 14, 4.5, 12, 10 and 20 ng/mL in the same order. The coefficients of variation for their intra- and inter-day assays were less than 7.8 and 9.4%, respectively. Of the other centrally acting drugs, only amoxapine interfered with the peak of DRO. Using our procedure, the binding study of tested compounds to synthetic melanin, human serum albumin and alpha1-acid glycoprotein was performed by determining the unbound concentration to total concentration ratio. These results indicated that simultaneous assay of HAL, R-HAL, FBPA, CPHP, SPI and DRO in phosphate-buffered saline by HPLC equipped with dual ultraviolet detection is simple, sensitive and reproducible. Also, our assay system can be applied to the binding study of these compounds to synthetic melanin, human serum albumin and alpha1-acid glycoprotein. 相似文献