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91.
Visible‐Light‐Mediated Addition of α‐Aminoalkyl Radicals to [60]Fullerene by Using Photoredox Catalysts 下载免费PDF全文
Dr. Yoshihiro Miyake Yuya Ashida Dr. Kazunari Nakajima Prof. Dr. Yoshiaki Nishibayashi 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(20):6120-6125
The functionalization of fullerene has been extensively studied and various fullerene derivatives have been synthesized. We have succeeded in the functionalization of [60]fullerene by using α‐aminoalkyl radicals generated by visible‐light‐mediated single‐electron oxidation of α‐silylamines as synthetic intermediates. In these reactions, the introduction of diarylamino groups, which are useful electron donors, has been easily achieved. 相似文献
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This paper describes the dynamics of a water-in-oil microemulsion from the dilute to the dense droplet region. Using the relative intermediate form factor method for neutron spin echo data analyses [M. Nagao, H. Seto, Phys. Rev. E 78 (2008) 011507], the shape and structure fluctuations of a droplet microemulsion are successfully decoupled. In the previous paper, we used the first cumulant analysis of the shape fluctuation model, while the full fitting form of the same model is applied in this paper. The final results of the fittings using the first cumulant approximation and the full form of the model are almost identical, and therefore, the validity of the method is strengthened. The estimated bending modulus of the surfactant membrane, κ, is basically the same, within the experimental errors, in the previous and present results. The κ is not affected much by an increase of the droplet concentration. A clear dynamic slowing down of the water droplets is highlighted at the length scale corresponding to the inter-droplet distance from the structure fluctuation analysis. 相似文献
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We revisited the vanadium oxide phosphors, AVO3 (A:K, Rb, and Cs) and M3V2O8 (A:Mg and Zn) for a revaluation of possibility of these compounds for lighting applications, and the internal quantum efficiency (η) and luminescent colour properties for AVO3 (A:K, Rb, and Cs) and M3V2O8 (A:Mg, and Zn) have been presented. The AVO3 showed the broadband emission from 380 to 800 nm, and the η for the KVO3, RbVO3 and CsVO3 were 4%, 79% and 87%, respectively. The CIE colour coordinates are located at white region on the chromaticity diagram. The M3V2O8 (A:Mg and Zn) also exhibited a quite broadband emission between 410 and 900 nm, indicating yellow luminescent colour. The Zn3V2O8 showed high η value, 52%, compared to that of the Mg3V2O8 (η=6%). This enhancement of η in the Zn3V2O8 could be due to the increasing exciton diffusion assisted by the hybridizations of Zn 3d and O 2p orbitals for the valence band, and Zn 4s and Ti 3d orbitals for the conduction band. 相似文献
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The spin polarizations of hadrons inclusively produced by pp, γp and λp collisions are studied by the quark rearrangement model. The present model is a phenomenological one based on the relativistic spin equations of motion and using the quark distribution functions in hadrons and photon. A general success of the model is demonstrated. We find usefulness of the present formulation for studying the dynamics producing spin asymmetry distributions and the statics determining signs and magnitudes of the spin polarization by reflecting the characteristic quark structure in hadrons. 相似文献
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We examined the formation of complexes between terbium ion (Tb3+) and carbohydrates labeled with aminobenzene compounds. Of the examined compounds, carbohydrates labeled with 4-aminosalicylic acid showed intense fluorescence with Tb3+ in the presence of cetylpyridinium chloride at pH 6.0. Calibration curves for maltose derivative showed good linearity between 5 pmol and at least 600 pmol, with good reproducibility. We applied the proposed technique to binding studies between manno-oligosaccharides and Concanavalin A. 相似文献
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[reaction: see text] Via an X-ray analysis, the sulfonamide bearing R(1) = i-Pr, R(2) = Me, and R(3) = Me is shown to be a tridentate ligand to a Cr(III) salt. This class of ligands, represented by R(1) = t-Bu, R(2) = 2-naphthyl, and R(3) = Me, is effective to achieve an asymmetric Ni/Cr-mediated coupling reaction and, with the C14-C38 segment of halichondrins, its synthetic potential has been demonstrated. A possible mechanism is suggested for the process. 相似文献