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51.
The excited-state dynamics of a bisimide derivative (ZI) and a novel Z1-C60 complex (PSF) has been investigated by means of steady state optical spectroscopies and femtosecond time-resolved absorption spectroscopies. The lifetime of the singlet excited state of Z1 shortens drastically from 2.4 ns to 1.7ps upon going from Z1 to PSF, a significant kinetics change is in coincidence with the complete fluorescence quench caused by the C^60 attachment.Highly efficient Zl-to-C60 excitation energy transfer which is governed by the mechanism of Z1-C60 electron exchange has been verified for the PSF complex.  相似文献   
52.
聚合物载体-稀土金属配合物的研究.聚(苯乙烯-4-乙烯基吡啶)钕配合物在丁二烯聚合中的催化行为李晓莉于广谦*李玉良(中国科学院长春应用化学研究所长春130022)关键词苯乙烯,乙烯基吡啶,共聚物,钕配合物,丁二烯聚合1996-04-11收稿,1996...  相似文献   
53.
C60的[3+2]环加成反应   总被引:2,自引:0,他引:2  
综述了C60的[3+2]环加成反应的研究进展。包括C60与亚胺叶立德、重氮化合物、叠氮化合物、氧化腈、腈亚胺、cis-HOCH2CH=CHCH2OCO2Et、1,8-二碘萘、环丙烯酮缩醛和Pyrazolidinium叶立德发生的[3+2]环加成反应。  相似文献   
54.
庞朝阳  李玉良 《中国物理快报》2006,23(12):3145-3147
We investigate the dynamics of genuine three-qubit entanglement in the Ising model of three spins. A scheme is presented for generating the genuine three-qubit entanglement by the nearest-neighbour couplings. The effect of magnetic fields on the dynamics of genuine three-qubit entanglement is also discussed.  相似文献   
55.
聚合物载体—稀土金属络合物的研究   总被引:2,自引:0,他引:2  
  相似文献   
56.
石墨炔特殊的电子结构和孔洞结构使其在信息技术、电子、能源、催化以及光电等领域具有潜在、重要的应用前景。近几年石墨炔的基础和应用研究已取得了重要成果,并迅速成为了碳材料研究中的新领域。石墨炔中炔键单元的高活性为其化学修饰与掺杂提供了良好的平台。在这篇综述中,我们将重点介绍石墨炔的非金属杂原子掺杂、金属原子修饰以及表面改性,并深入探讨掺杂与衍生化对石墨炔材料的电子性质的影响及其对光电化学催化性能的协同增强。  相似文献   
57.
After briefly introducing Akhtarshenas, concurrence vector and subvector for describing many-body entanglement, we investigate the entanglement formation for a system which contains three bodies, i.e. two identical atoms and a single- model cavity field, in the Tavis-Cummings model by calculating the concurrences. The results show that the coupling strength between two atoms, the decay cavity and the atomic spontaneous emission can change the entanglement of formation according to different modes: these factors destroy periodicity and symmetry of all concurrences, and that the coupling strength of two atoms does not change the peak value of concurrence (C), but the strength of decay cavity and the atomic spontaneous emission decline in the peak value of concurrence (C) and the latter is more serious than the former under the same strengths. The concurrence vector and subvector are a useful measure of entanglement for a pure state of the many-body system, in that it can give novel pictures about the entanglements for the entire system and between its inner bodies.  相似文献   
58.
众所周知,在烯烃络合催化聚合中,过渡金属配位体的种类是影响催化剂活性的重要因素之一.用高分子代替小分子作为配位体,影响催化剂的活性因素则由原来单一的固定因素变成多重的可变因素.高分子金属络合物的结构因素,如金属含量、功能团含量,金属与功能团的含量比都将直接影响催化活性.本文从聚合物的微观结构角度,研究了作为载体的苯乙烯-丙烯酸共聚物中单体单元的序列分布及其与催化活性的关系.  相似文献   
59.
Pore structure of the porous polydivinylbenzene microspheres is controlled by the degreeof crosslinkage and the diluent used. It is proved by chromatographic results that the higher thedegree of crosslinkage is, the more the micellar pores will be formed, and the nature as wellas the quantity of the diluent determine the real pore structure. Among the structural para-meters of the microspheres, the size and the pore diameter affect the performance in HPLCmostly. The linear sample capacity of the microspheres in 1--2 order of magnitude larger thanthat of the Silica-ODS. According to this result, it could be confirmed that the solute mole-cules penetrate deeply into the skeleton of the polymer network. Based on the polymeric struc-ture with the same chemical composition but different in pore structure, the contribution tothe retention of several organic compounds by Henry's and/or adsorption coefficient has beenstudied. The results obtained show that Henry's coefficient is approximately 80% of thetotal contribution, i. e. dissolution mechanism plays the main role in the chromatographicprocess, especially in case of polar compounds. The experimental result that the chroma-tographic separation relatively slightly depends upon the sueface area of the polymer isanother ovidence. It is better to define this kind of polymeric stationary phase as a sorbentrather than an adsorbent. From the point of view of dissolution mechanism, it is suggestedthat a homogeneous porous polymeric stationary phase constructed with chemically rigid ske-letal structure and sufficiently thin bulk polymeric phase inside the microspheres should bean ideal packing for chromatography.  相似文献   
60.
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