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1.
Embedding endohdedral metallofullerenes (EMFs) into electron donor–acceptor systems is still a challenging task owing to their limited quantities and their still largely unexplored chemical properties. In this study, we have performed a 1,3‐dipolar cycloaddition reaction of a corrole‐based precursor with Sc3N@C80 to regioselectively form a [5,6]‐adduct ( 1 ). The successful attachment of the corrole moiety was confirmed by mass spectrometry. In the electronic ground state, absorption spectra suggest sizeable electronic communications between the electron acceptor and the electron donor. Moreover, the addition pattern occurring at a [5,6]‐bond junction is firmly proven by NMR spectroscopy and electrochemical investigations performed with 1 . In the electronically excited state, which is probed in photophysical assays with 1 , a fast electron‐transfer yields the radical ion pair state consisting of the one‐electron‐reduced Sc3N@C80 and of the one‐electron‐oxidized corrole upon its exclusive photoexcitation. As such, our results shed new light on the practical work utilizing EMFs as building blocks in photovoltaics.  相似文献   
2.
Set-Valued and Variational Analysis - We aim to establish Karush-Kuhn-Tucker multiplier rules involving higher-order complementarity slackness under Hölder metric subregularity. These rules...  相似文献   
3.
4.
This paper reports that the growth of RuOx(110) thin layer growth on Ru(0001) has been investigated by means of scanning tunnelling microscope (STM). The STM images showed a domain structure with three rotational domains of RuOx(110) rotated by an angle of 120℃. The as-grown RuOx(110) thin layer is expanded from the bulk-truncated RuOx(110) due to the large mismatch between RuOx(110) and the Ru(0001) substrate. The results also indicate that growth of RuOx(110) thin layer on the Ru(0001) substrate by oxidation tends first to formation of the Ru-O (oxygen) chains in the [001] direction of RuOx(110).  相似文献   
5.
Langduin C, a novel dimeric diterpenoid, was isolated from the roots of Euphorbia fischeriana and its structure was established by spectral data and single-crystal X-ray diffraction analysis.  相似文献   
6.
Rhythmic growth of ring‐banded spherulites in blends of liquid crystalline methoxy‐poly(aryl ether ketone) (M‐PAEK) and poly(aryl ether ether ketone) (PEEK) has been investigated by means of differential scanning calorimetry (DSC), polarized light microscopy (PLM), and scanning electron microscopy (SEM) techniques. The measurements reveal that the formation of the rhythmically grown ring‐banded spherulites in the M‐PAEK/PEEK blends is strongly dependent on the blend composition. In the M‐PAEK‐rich blends, upon cooling, an unusual ring‐banded spherulite is formed, which is ascribed to structural discontinuity caused by a rhythmic radial growth. For the 50:50 M‐PAEK/PEEK blend, ring‐banded spherulites and individual PEEK spherulites coexist in the system. In the blends with PEEK as the predominant component, M‐PAEK is rejected into the boundary of PEEK spherulites. The cooling rate and crystallization temperature have great effect on the phase behavior, especially the ring‐banded spherulite formation in the blends. In addition, the effects of M‐PAEK phase transition rate and phase separation rate on banded spherulite formation is discussed. © 2007 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 45: 3011–3024, 2007  相似文献   
7.
利用电弧熔炼制备了 (Nd1 xErx) 2 Co1 5 5V1 5(x=0— 1 0 )化合物样品 .通过x射线衍射分析和磁性测量研究了Er替代Nd2 Co1 5 5V1 5中的Nd时对化合物结构和磁性的影响 .研究结果表明 ,低Er含量 (x <0 4 ) ,化合物为Th2 Zn1 7型结构 ;高Er含量时 (x >0 5 ) ,化合物转变为Th2 Ni1 7结构 ;Er含量为x =0 4和 0 5时 ,两种结构共存 .两种结构的晶胞参数a ,c和晶胞体积V随着Er含量的增加都呈现递减的趋势 .随着Er含量的增加 ,(Nd1 xErx) 2 Co1 5 5V1 5化合物的居里温度和饱和磁化强度都单调下降 .(Nd1 xErx) 2 Co1 5 5V1 5化合物的室温各向异性由低Er含量时的易锥型转变为高Er含量时的易轴型 .x =0— 0 5的化合物在温度升高时发生自旋重取向转变 ,自旋重取向温度Tsr随Er含量的增加而减小  相似文献   
8.
An unusual reductive ring-opening reaction of phthalimide with sodium hydride in anhydrous DMF was observed for the first time. The presumed mechanism was described in detail.  相似文献   
9.
This note chronicles various roles played by the Yasuda-Shimada theorem in some recent developments of Riemann--Finsler geometry. We shall demonstrate that the said theorem is, at various stages of its life, an enigma, an inspiration, a flawed icon, and a powerful catalyst.  相似文献   
10.
In this paper, a unified approach for analysing finite dimensional approximations to a class of partial differential equations boundary value problems (second‐kind Fredholm differential equations) is introduced. The approach is shown to be general despite of its extremely simple form. In particular, it is expected to be useful in the convergence analysis of finite element methods for solving PDE problems. Three specific examples are presented to illustrate the broad applicability of the approach. Copyright © 2004 John Wiley & Sons, Ltd.  相似文献   
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