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991.
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993.
Nikita K. Kulachenkov Dr. Dapeng Sun Yuri A. Mezenov Dr. Andrei N. Yankin Sergey Rzhevskiy Dr. Vyacheslav Dyachuk Dr. Alexandre Nominé Dr. Ghouti Medjahdi Prof. Evgeny A. Pidko Dr. Valentin A. Milichko 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(36):15652-15656
We demonstrate herein an all-optical switch based on stimuli-responsive and photochromic-free metal–organic framework (HKUST-1). Ultrafast near-infrared laser pulses stimulate a reversible 0.4 eV blue shift of the absorption band with up to 200 s−1 rate due to dehydration and concomitant shrinking of the structure-forming [Cu2C4O8] cages of HKUST-1. Such light-induced switching enables the remote modulation of intensities of photoluminescence of single crystals of HKUST-1 as well visible radiation passing through the crystal by 2 order of magnitude. This opens up the possibility of utilyzing stimuli-responsive MOFs for all-optical data processing devices. 相似文献
994.
995.
This Letter investigates all-optical magnetization switching from micromagnetic perspective. The influence of circularly polarized light on a magnetic sample was considered to be both directly through the inverse Faraday effect and indirectly aided by thermal induced effects by the laser beam. Dependence of all-optical switching on pulse duration, laser intensity and the magneto-optical susceptibility strength is studied. An important aspect of this investigation is the analysis of how the cooling process influences the successive switches, especially through limiting the successive writing time. 相似文献
996.
Anthracene-based cylindrical macrotricyclic polyether (1) containing two dibenzo-30-crown-10 cavities has been proved to be an efficient host for the templated complexation with N,N’-dipropyl-1,4,5,8-naphthalenetetracarboxylic diimide in the presence of lithium ions in both solution and solid state. Host 1 could also form 1:1 complex with the bispyridinium salt with two β-hydroxyethyl groups in solution and in the solid state. Moreover, it was also found that the switchable complexation processes between the macrotricyclic host and two different kinds of guests could be chemically controlled by the addition and removal of lithium ions. 相似文献
997.
集成化发展趋势是射频系统的重要发展趋势之一,其中,有源开关与无源滤波器组的组合是射频集成宽带系统的常用电路单元之一。由于二者采用了不同的制造工艺,其加工工艺与材料组成均不同。因此,将二者高密度集成时须借助于其他介质。文中根据集成无源器件技术和高密度封装技术的发展进度,完成了一种S波段的有源开关带通滤波器组的研制,产品尺寸为7.0 mm×5.5 mm×1.14 mm,且内集成隔直电容和电源去耦电容,在实现了小型化、轻量化的同时,其工程应用将十分便利。 相似文献
998.
Ping Shen Shuzhang Xiao Xuqin Zhan Wei Zhang Kedi Chang Changying Yang 《Journal of Physical Organic Chemistry》2013,26(10):858-862
A pH fluorescent molecular switch, BOPIM‐dma, a boron 2‐(2′‐pyridyl) imidazole complex derivatives, was investigated in aqueous system. BOPIM‐dma shows weak or no fluorescence in conventional solvents due to twisted intramolecular charge transfer (TICT). Upon protonation of the dimethylamino groups in BOPIM‐dma, its fluorescence was turned on ascribed to the inhibition of TICT. Its emission can be switched ‘on’ or ‘off’ between pH 2.4 and 4.0, and it undergoes a reversible protonation–deprotonation reaction with a pKa of 3.12. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
999.
针对并联供电中各电源模块参数的分散性,导致输出电流的不均衡,结果分担电流多的模块热应力大,降低了系统的可靠性等问题,提出了具有均流技术的开关并联供电系统的设计. 相似文献
1000.
A new hybrid scheme is proposed, which combines the improved third‐order weighted essentially non‐oscillatory (WENO) scheme presented in this paper with a fourth‐order central scheme by a novel switch. Two major steps have been gone through for the construction of a high‐performance and stable hybrid scheme. Firstly, to enhance the WENO part of the hybrid scheme, a new reference smoothness indicator has been devised, which, combined with the nonlinear weighting procedure of WENO‐Z, can drive the third‐order WENO toward the optimal linear scheme faster. Secondly, to improve the hybridization with the central scheme, a hyperbolic tangent hybridization switch and its efficient polynomial counterpart are devised, with which we are able to fix the threshold value introduced by the hybridization. The new hybrid scheme is thus formulated, and a set of benchmark problems have been tested to verify the performance enhancement. Numerical results demonstrate that the new hybrid scheme achieves excellent performance in resolving complex flow features, even compared with the fifth‐order classical WENO scheme and WENO‐Z scheme. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献