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1.
Y. KatoD. Ichii K. OhashiH. Kunugita K. Ema K. TanakaT. Takahashi T. Kondo 《Solid State Communications》2003,128(1):15-18
We have confirmed biexciton formation in an organic-inorganic hybrid quantum-well material (C4H9NH3)2PbBr4 by photoluminescence and two-photon absorption measurements. The biexciton has extremely large binding energy, 60 meV, which to our knowledge is the largest value ever reported for a semiconductor. By analyzing the spectrum of biexciton luminescence, the biexciton gas temperature was found to be much higher than the bath temperature due to a higher local temperature arising from the large biexciton binding energy. 相似文献
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A palladium NNC‐pincer complex at a 5 mol ppm loading efficiently catalyzed the Hiyama coupling reaction of aryl bromides with aryl(trialkoxy)silanes in propylene glycol to give the corresponding biaryls in excellent yields. This method was applied to the syntheses of adapalene and a biaryl‐type liquid‐crystalline compound, as well as to the derivatization of dextromethorphan and norfloxacin. ESI‐MS and NMR analyses of the reaction mixture suggested the formation of pentacoordinate spirosilicate intermediates in situ. Preliminary theoretical studies revealed that the glycol‐derived silicate intermediates formed in situ are quite reactive silicon reagents in the transmetalation step. 相似文献
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Yang J Ichii T Murase K Sugimura H 《Langmuir : the ACS journal of surfaces and colloids》2012,28(20):7579-7584
We have fabricated gold nanoparticle (AuNP) arrays on indium-tin oxide (ITO) substrates in a nearly one-dimensional fashion. AuNPs were site-selectively immobilized on ITO of which the surface had been patterned by a nanolithography process based on scanning probe microscopy. The fabricated nanoscale lines covered with aminosilane self-assembled monolayer served as chemisorption sites for citrate-stabilized AuNPs of 20 nm in diameter, accordingly, AuNP nanolines with a thickness of single nanoparticle diameter were spontaneously assembled on the lines. In this 1D array, the AuNPs were almost separated from each other due to the electrostatic repulsion between their negatively charged surface layers. Furthermore, a reorganization process of the immobilized AuNP arrays has been successfully demonstrated by replacing each AuNP's surface layer from citric acid to dodecanethiol. By this process, the AuNPs lost their electrostatic repulsion and became hydrophobic so as to be attracted to each other through hydrophobic interaction, resulting in reorganization of the AuNP array. By repeating the deposition and reorganization cycle, AuNPs were more densely packed. The optical absorption peak of the arrays due to their plasmonic resonance was found to shift from 526 to 590 nm in wavelength with repeating cycles, indicating that the resonance manner was changed from the single nanoparticle mode to the multiple particle mode with interparticle coupling. 相似文献
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Hiroshige Ryosuke Goto Satoru Tsunoda Chihiro Ichii Risa Shimizu Shota Otsuka Yuta Makino Kosho Takahashi Hideyo Yokoyama Hideshi 《Journal of inclusion phenomena and macrocyclic chemistry》2022,102(9-10):791-800
Journal of Inclusion Phenomena and Macrocyclic Chemistry - Ketoprofen is a nonsteroidal anti-inflammatory drug used as mohrus tape which causes unwanted photosensitivity due to UV irradiation. In... 相似文献
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Direct Synthesis of Benzofuro[2,3‐b]pyrroles through a Radical Addition/[3,3]‐Sigmatropic Rearrangement/Cyclization/Lactamization Cascade 下载免费PDF全文
Dr. Masafumi Ueda Yuta Ito Yuki Ichii Maiko Kakiuchi Hiroko Shono Prof. Dr. Okiko Miyata 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(22):6763-6770
A straightforward synthetic method for the construction of benzofuro[2,3‐b]pyrrol‐2‐ones by a novel domino reaction through a radical addition/[3,3]‐sigmatropic rearrangement/cyclization/lactamization cascade has been developed. The domino reaction of O‐phenyl‐conjugated oxime ether with an alkyl radical allows the construction of two heterocycles with three stereogenic centers as a result of the formation of two C?C bonds, a C?O bond, and a C?N bond in a single operation, leading to pyrrolidine‐fused dihydrobenzofurans, which are not easily accessible by existing synthetic methods. Furthermore, asymmetric synthesis of benzofuro[2,3‐b]pyrrol‐2‐one derivatives through a diastereoselective radical addition reaction to a chiral oxime ether was also developed. 相似文献
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An optical ring circuit with two spatial light modulators is capable of supporting a variety of nonlinear spatio-temporal dynamics, including an array of bistable spots with novel Trigger-type flip-flop operation. 相似文献
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Sugimura H Moriguchi T Kanda M Sonobayashi Y Nishimura HM Ichii T Murase K Kazama S 《Chemical communications (Cambridge, England)》2011,47(31):8841-8843
The molecular density of an aminosilane self-assembled monolayer formed from N-(2-aminoethyl)-3-aminopropyltriethoxysilane (AEAPS) by a vapor phase method has been estimated to be about 3 AEAPS molecules per nm(2) based on chemical labeling, optical absorption spectroscopy and X-ray photoelectron spectroscopy. 相似文献
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Ueda M Kondoh E Ito Y Shono H Kakiuchi M Ichii Y Kimura T Miyoshi T Naito T Miyata O 《Organic & biomolecular chemistry》2011,9(7):2062-2064
Direct generation of a benzyl radical by C-H bond activation of toluenes and the addition reaction of the resulting radical to an electron deficient olefin were developed. The reaction of dimethyl fumarate with toluene in the presence of Et(3)B as a radical initiator at reflux afforded 2-benzylsuccinic acid dimethyl ester in good yield. 相似文献
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Kurimoto A Tobe M Ogita H Ogino T Takaku H Ichii S Kawakami H Isobe Y 《Chemical & pharmaceutical bulletin》2004,52(4):466-469
In order to improve the oral bioavailability of 9-benzyl-8-hydroxy-2-(2-hydroxyethylthio)adenine (SM-295072), a potent interferon (IFN) inducing agent, we synthesized prodrugs of it by utilizing the hydroxy groups at the C(2)-side chain and/or the C(8)-position. The carbonate prodrug at the C(8)-position was more effective than that at the C(2)-side chain for oral absorption in rats. Among the compounds prepared, compound 6 demonstrated the most preferable prodrug properties, and the maximum plasma concentration of 6 was approximately 4-fold higher than that of SM-295072. Furthermore, compound 6 was dose-dependently absorbed in monkeys by oral administration, and exhibited a potent IFN-inducting activity that correlated well with its plasma drug concentration. 相似文献