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101.
In this paper, we investigate the complete moment convergence for dependent linear processes with random coefficients to form 相似文献
102.
能源互联网呈现物理信息深度融合的趋势,为电力系统管理研究定义了新的研究框架。作为一个先进的复杂系统,能源互联网信息物理系统(Energy Internet Cyber-Physical System,ECPS)在其发展过程中面临着一些新的挑战,其中一个就是耦合结构下的风险管理。本文结合复杂网络理论和风险传递理论,着重在拓扑层面分析了ECPS跨空间交互机理,并在此基础上定义了交互路径和交互系数;接着建立了ECPS跨空间风险传递模型,量化描述了风险的传递和演化过程,并进行了风险影响评估;最后,通过仿真实验分析了三种不同交互系数节点故障的风险传递过程和不同攻击模式下系统的崩溃过程。对仿真结果的讨论阐述了能源互联网风险跨空间传递的特点,为更深入地研究ECPS的风险管理提供了参考。 相似文献
103.
Two new coordination complexes based on benzimidazole dicarboxylic acid, Zn(Hbidc)?H2O ( 1 ) and Cd(Hbidc)(H2O) ( 2 ), have been synthesized under hydrothermal conditions. The complexes were characterized using elemental analysis, infrared and UV–visible spectroscopies, powder X‐ray diffraction, thermogravimetry and single‐crystal X‐ray diffraction. Structural analyses showed that the crystal structures of 1 and 2 are different, due to the various modes of linking of the benzimidazole dicarboxylic acid. Complex 1 has a two‐dimensional network structure and 2 has a three‐dimensional network structure. In addition, we studied the performance of the fluorescence response of two complexes. Results showed that the complexes can be used as chemical sensors for multifunctional testing, such as for UO22+, xanthine and Fe3+ ions. Even if the concentration is very low, they could also be detected, showing that coordination complexes 1 and 2 have very high fluorescence sensitivity. The detection limit for UO22+ is 5.42 nM ( 1 ) and 0.02 nM ( 2 ), that for xanthine is 1.37 nM ( 1 ) and 0.28 nM ( 2 ), and that for Fe3+ ions is 0.76 nM ( 1 ) and 0.62 nM ( 2 ). 相似文献
104.
Rik H. Verschueren Julie Schmauck Dr. Michael S. Perryman Dr. Hui-Lan Yue Julian Riegger Dr. Bertrand Schweitzer-Chaput Dr. Martin Breugst Dr. Martin Klussmann 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(38):9088-9097
In this work, the reactivities of acetonyl and benzoyl radicals in aromatic substitution and addition reactions have been compared in an experimental and computational study. The results show that acetonyl is more electrophilic than benzoyl, which is rather nucleophilic. A Hammett plot analysis of the addition reactions of the two radicals to substituted styrenes clearly support the nucleophilicity of benzoyl, but in the case of acetonyl, no satisfactory linear correlation with a single substituent-related parameter was found. Computational calculations helped to rationalize this effect, and a good linear correlation was found with a combination of polar parameters (σ+) and the radical stabilization energies of the formed intermediates. Based on the calculated philicity indices for benzoyl and acetonyl, a quantitative comparison of these two radicals with many other reported radicals is possible, which may help to predict the reactivities of other aromatic radical substitution reactions. 相似文献
105.
Yan‐Ping Zhang Yue Li Guan‐Cheng Xu Jin‐Yu Li Hua‐Ying Luo Jin‐Yao Li Li Zhang Dian‐Zeng Jia 《应用有机金属化学》2019,33(3)
Two new complexes, namely [Cu6L6] ( 1 ) and [Zn(HL)2] ( 2 ) (H2L = N‐(1‐phenyl‐3‐methyl‐4‐propenylidene‐5‐pyrazolone)‐2‐furancarboxylic acid hydrazide), have been synthesized and characterized. Single crystal X‐ray analysis indicates that complex 1 has a hexanuclear structure and complex 2 exhibits a mononuclear structure. The DNA/bovine serum albumin (BSA) binding properties of complexes 1 and 2 were investigated by absorption spectroscopy and fluorescence quenching. Both complexes could effectively intercalate to DNA with calculated quenching constants of 2.6 × 105 and 1.25 × 105 M?1, respectively. The quenching mechanism of the intrinsic fluorescence of BSA by the complexes was found to be a static one. The cytotoxicities of 1 and 2 were investigated in two human tumor cell lines, human esophageal cancer cells (Eca‐109) and cervical cancer cells (HeLa). Complex 1 exhibits higher antitumor activity than 2 . Furthermore, 1 can inhibit HeLa cells by inducing apoptosis and G0/G1 phase cell cycle arrest. All results demonstrate that 1 and 2 both have DNA/BSA binding capacity and antitumor activity. 相似文献
106.
Two LnIII ions are sandwiched by dinuclear CoII building blocks derived from a tris‐triazamacrocyclic ligand bearing pendant carboxylic acid functionality, 1,3,5‐tris((4,7‐bis(2‐carboxyethyl)‐1,4,7‐triazacyclonon‐1‐yl)methyl)‐benzene (H6L), giving rising to two nanoscale heterometallic metal–organic cages formulated as [Co4Ln2(LH2.5)2(H2O)4]·(ClO4)6·NO3·nH2O [Ln = Dy, n = 12 ( 1 ); Ln = Yb, n = 9 ( 2 )], whose internal cavity accommodates a guest NO3? anion. Their hexanuclear cage‐like architectures are maintained both in solution and solid states as confirmed by mass spectrum as well as X‐ray diffraction experiments. These two cages display ligand‐based fluorescence emissions and therefore both were chosen to be operated as fluorescent chemosensors for the detection of nitroaromatic compounds. Attractively, these metal–organic cages allow highly selective and sensitive detection of picric acid (PA) over other nitroaromatics in solution and suspension, and the fluorescence resonance energy transfer (FRET) between the cage probes and PA is mainly responsible for the remarkable detection efficiency. 相似文献
107.
Verena Bögelein Frank Duzaar Leah Schätzler Christoph Scheven 《Journal of Differential Equations》2019,266(11):7709-7748
We establish that solutions to the Cauchy–Dirichlet problem for functionals of linear growth can be obtained as limits of solutions to flows with p-growth in the limit . The result can be interpreted on the one hand as a stability result. On the other hand it provides an existence result for general flows with linear growth. 相似文献
108.
Carsten Lenczyk Dr. Dipak Kumar Roy Bijoy Ghosh Johannes Schwarzmann Prof. Ashwini K. Phukan Prof. Dr. Holger Braunschweig 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(36):8585-8589
A series of bis(σ)-borane complexes of Group 6 transition metals were prepared by direct dihydroborane coordination to the metal center. Reaction of [M(CO)3(PCy3)2] and two dihydroboranes [DurBH2] and [(Me3Si)2NBH2] (Dur=2,3,5,6-Me4C6H) yielded bis(σ)-borane complexes fac-[M(CO)3(PCy3){η2-(H2BR)}] (R=Dur; 1 : M=Cr, 2 : M=W; R=N(SiMe3)2; 3 : M=Cr, 4 : M=W). In the case of molybdenum, we have isolated an arene complex ( 5 ) with [DurBH2] in which the Dur group acts as a η6-bound ligand, and with [(Me3Si)2NBH2] a similar bis(σ)-borane complex was isolated, cis,trans-[Mo(CO)2(PCy3)2{η2-(H2BN(SiMe3)2}] ( 6 ), with a different pattern of auxiliary ligands. The complexes were investigated by multinuclear NMR spectroscopy, mass spectrometry, X-ray diffraction analysis, and computational methods. Quantum theory of atoms in molecules (QTAIM) calculations demonstrated that the borane complexes may be described as pure bis(σ)-borane complexes rather than elongated or stretched examples given that the calculations do not show the presence of a ring-critical point (RCP) at the ring formed by the interactions of the B−H with metal center. 相似文献
109.
A linear optical unambiguous discrimination of hyperentangled Bell states is proposed for two‐photon systems entangled in both the polarization and momentum degrees of freedom (DOFs) assisted by time bin. This unambiguous discrimination scheme can completely identify 16 orthogonal hyperentangled Bell states using only linear optical elements, where the function of the auxiliary entangled Bell state is replaced by time bin. Moreover, the possibility of extending this scheme for distinguishing hyperentangled Bell states in n DOFs is discussed, and it shows that hyperentangled Bell states in n ( ) DOFs can be distinguished with k ( ) auxiliary entangled states of additional DOFs by introducing a time delay, which decreases the auxiliary entanglement resource required for unambiguous discrimination of hyperentangled Bell state. Therefore, this scheme provides a new way for distinguishing hyperentangled states with current technology, which will extend the application of discrimination of hyperentangled states via linear optics to other quantum information protocols besides hyperdense coding schemes in the future. 相似文献
110.
针对设计的一种场畸变气体开关,研究中间电极材料分别为不锈钢和黄铜条件下的烧蚀特性,结合开关寿命期间静态与触发特性的变化规律,获得决定开关寿命的关键因素,为三电极场畸变气体开关的性能优化提供理论支撑。研究结果表明,采用不锈钢和黄铜作为中间电极的烧蚀区域以及表面粗糙度均随着放电次数增加而增大,黄铜电极烧蚀较为严重且表面有明显的烧蚀圆斑,不锈钢电极则具有更高的表面粗糙度,阴阳极表面烧蚀存在明显差异,随着放电次数的增加,击穿点向电极边缘区域集中,影响开关的沿面绝缘特性,是导致开关寿命终结的主要原因。 相似文献