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21.
Transalkylation of Higher Trifluoromethylated Fullerenes with C70: A Pathway to New Addition Patterns of C70(CF3)8
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Nikita M. Belov Marina G. Apenova Alexey V. Rybalchenko Eugenia V. Borkovskaya Dr. Natalia S. Lukonina Dr. Alexey A. Goryunkov Dr. Ilya N. Ioffe Prof. Dr. Sergey I. Troyanov Prof. Dr. Lev N. Sidorov 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(4):1126-1133
We report three new isomers of C70(CF3)8, structurally related to p7mp‐C70(CF3)10, that are inaccessible by direct trifluoromethylation, but can be easily identified among the products of the transalkylation of higher trifluoromethylfullerenes with C70. The reported compounds are characterized by UV/Vis, 1 D and 2 D COSY 19F NMR spectroscopy, and DFT calculations. A rather unusual addition pattern is observed in p6,i‐C70(CF3)8 in which one addend is attached remotely from the others; polarization of the adjacent unsaturated bonds by the addend makes the molecule readily oxidizable. 相似文献
22.
Ruixiang Qu Xiangyu Li Yanan Liu Huajun Zhai Shuaiheng Zhao Lin Feng Yen Wei 《Angewandte Chemie (International ed. in English)》2020,59(32):13437-13443
Superwetting membranes with responsive properties have attracted heightened attention because of their fine‐tunable surface wettability. However, their functional diversity is severely limited by the “black‐or‐white” wettability transition. Herein, we describe a coating strategy to fabricate multifunctional responsive superwetting membranes with SiO2/octadecylamine patterns. The adjustable patterns in the responsive region are the key factor for functional diversity. Specifically, the coated part of the membrane displayed a superhydrophobicity/superhydrophilicity transition at different pH values, whereas the uncoated part exhibited invariant superhydrophilicity. On the basis of this anisotropy/isotropy transition, the membranes can serve as either responsive permeable membranes or signal‐expression membranes, thus enabling the responsive separation and permeation of liquids with satisfactory separation efficiency (>99.90 %) and flux (ca. 60 L m?2 h), as well as real‐time liquid signal expression with alterable signals. 相似文献
23.
《Physics letters. A》2020,384(22):126535
We consider the mass-imbalanced sensibility for the emergence of vortex patterns in the Bose-Einstein condensed binary mixture of rubidium-cesium (85Rb-133Cs), confined in quasi-two-dimensional harmonic traps, with one species linearly perturbed in one direction. Non-dipolar coupled species are chosen to highlight mass symmetry effects. We first analyze the condensed mixture in the unperturbed non-rotating regime, where radial phase separation is verified in the immiscible regime, which occurs for large ratio between inter- and intra-species repulsive interactions. By going to the linear perturbed regime, the radial phase separation that occurs in the immiscible condition splits up with the two densities having their maxima at distinct positions. In the rotating regime of both unperturbed and perturbed cases, the minimum rotation is determined in terms of the inter-species interaction to observe vortex structures. In the immiscible regime a dramatic spatial interchange between the species is verified by increasing the rotation. 相似文献
24.
针对振动陀螺仪单向时滞耦合系统,研究了角速度、耦合强度、耦合时滞与系统输出信号之间的关系,着重关注耦合时滞对待检测角速度测量结果的影响.本文采用摄动法对振动陀螺仪单向时滞耦合系统进行理论分析,得到了系统输出信号、系统振动边界和待检测角速度的近似表达式,并将数值和近似计算结果进行了对比.理论分析结果与数值结果比较吻合,验证了运用摄动法分析振动陀螺仪单向时滞耦合系统的有效性,也表明了在运用摄动法分析系统时具有局限性. 相似文献
25.
以陆生植物美人蕉(Canna generalis)、紫背万年青(Rhoeo discolor)为对象,研究了其不同的种植方式对净化富营养化水体中磷的影响.结果表明,美人蕉、紫背万年青的双倍生物量组对水体中TP、DTP和DIP的去除率与它们的单倍生物量组呈显著性差异,植物对水体中P的去除效果随着植物生物量的适度增加而提高.两种陆生植物的复合种植体系对TP、DTP和DTP的去除率和单一种植体系差别不明显,说明美人蕉、紫背万年青的不同种植体系对水体中TP、DTP和DIP去除率的影响不大.从美人蕉、紫背万年青去除水体中TP、DTP和DIP的动态过程拟合模型可以看出各植物处理组对水体中不同形态P有良好的去除效应. 相似文献
26.
A computer simulation system of three-dimensional sensing with structured illumination is presented. It includes the generation of deformed fringe patterns from 3-D shapes and the reconstruction of 3-D shapes, conversely. Some experimental results of the deformed fringe pattern and the reconstructed object shapes are presented. We have also discussed the effect of some major system parameters on the measurement results and considered how to correct these parameters according to the measurement result of the standard plane. Using this simulation system, the major system parameters: environmental conditions, measurement accuracy and algorithm evaluation of the 3-D shape measurement system based on PMP, FTP, SPM, etc., can be researched. © 1997 Elsevier Science Ltd. All rights reserved. 相似文献
27.
LI Ding 《中国物理C(英文版)》2008,32(2):160-164
We use Monte Carlo simulation to calculate the distributions of particles under adsorption force near planar and cylindrical surfaces,respectively.Both hard sphere interaction and repulsive Yukawa (screened coulomb) interaction are employed in our simulations.We study the influence of the inter-particle potentials.The difference between the MC simulation results and the analytical results of ideal gas model shows that the interaction between particles plays an important role in the density distribution under external fields.Moreover,the 2-dimensional constructions of particles close to the surface are studied and show relations of the interaction between particles.These results may indicate us how to improve the methods of building nanoparticle coatings and nano-scale patterns. 相似文献
28.
Shuai Huang Huanxi Zheng Jiyu Liu Jinlong Song Faze Chen Xiaolong Yang 《Journal of Dispersion Science and Technology》2017,38(4):566-569
Selective fabrication of superhydrophilic (S-philic) region on a superhydrophobic (S-phobic) surface requires complex technology and high cost, which has limited applications of extreme wettability patterns. In this paper, a twice-chemical-etching approach without special modification is used to prepare the extreme wettability patterns. Superhydrophobicity and superhydrophilicity can be successfully achieved after twice chemical etching for 20 seconds. The obtained patterns can maintain their extreme wettability for at least 30 days. Functional platforms with single-S-philic and multi-S-philic regions are fabricated to manipulate water and various organic liquids with water-film protection in an air environment. 相似文献
29.
A modified derivative sign binary method is proposed to extract fringe skeletons from interferometric fringe patterns. A fringe direction map ranging from 0° to 360° is obtained with an unambiguous relationship between the grayscale and fringe tangent direction. Using this approach, the derivative sign binary map is detected without a fringe direction jump. The dark (light) fringe intensity minimum (maximum) can be extracted automatically to define fringe skeletons. In addition, two different anisotropic one-dimensional filters are described that can be used for further improving the fringe quality. Examples are provided for a holographic interferogram and a Moiré fringe pattern to illustrate applications and benefits of the approach. 相似文献
30.
In this paper we explore the relation between information patterns and Nash Equilibria in extensive games. By information we mean what players know about moves made by others, as well as by chance. For the most part we confine ourselves to pure strategies. But in Section 2 behavioral strategies are also examined. It turns out that they can be modeled as pure strategies of an appropriately enlarged game. Our results, applied to the enlarged game, can then be reinterpreted in terms of the behavioral strategies of the original game. 相似文献