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71.
72.
Ideal optomechanically induced transparency generation in a cavity optoelectromechanical system 下载免费PDF全文
《中国物理 B》2021,30(10):104211-104211
The ideal optomechanically induced transparency effects of an output probe field are investigated in a cavity optoelectromechanical system, which is composed of an optical cavity, a charged mechanical resonator, and a charged object.Although the charged mechanical resonator damping rate is nonzero, the ideal optomechanically induced transparency can still appear due to the non-rotating wave approximation effect in the system. The location of optomechanically induced transparency dip can be controlled via the Coulomb coupling strength. In addition, we find that both the transparency window width and the maximum dispersion curve slope are closely related to the optical cavity decay rate. 相似文献
73.
Yu-Yi Zhang De-Shan Zhang Tian Li Dr. Mohamedally Kurmoo Prof. Dr. Ming-Hua Zeng 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(3):721-728
Dehydration of (S,S)-1,2-bis(1H-benzo[d]imidazol-2-yl)ethane-1,2-diol (H4L) to (Z)-1,2-bis(1H-benzo[d]imidazol-2-yl)ethenol) (H3L′) was found to be metal-assisted, occurs under solvothermal conditions (H2O/CH3OH), and leads to [MnII4(H3L)4Cl2]Cl2 ⋅ 5 H2O ⋅ 5 CH3OH ( Mn4L4 ) and [MnII4(H2L′)6(μ3-OH)]Cl ⋅ 4 CH3OH ⋅ H2O ( Mn4L′6 ), respectively. Their structures were determined by single-crystal XRD. Extensive ESI-MS studies on solutions and solids of the reaction led to the proposal consisting of an initial stepwise assembly of Mn4L4 from the reactants via [MnL] and [Mn2L2] below 80 °C, and then disassembly to [MnL] and [MnL2] followed by ligand modification before reassembly to Mn4L′6 via [MnL′], [MnL′2], and [Mn2L′3] with increasing solvothermal temperature up to 140 °C. Identification of intermediates [Mn4LxL′6−x] (x=5, 4, 3, 2, 1) in the process further suggested an assembly/disassembly/in situ reaction/reassembly transformation mechanism. These results not only reveal that multiple phase transformations are possible even though they were not realized in the crystalline state, but also help to better understand the complex transformation process between coordination clusters during “black-box” reactions. 相似文献
74.
Three one-dimensional ladder-like coordination polymers consisting of Cd6 metalloring as the building unit, {[Cd4LCl4]·3H2O}n ( 1 ), {[Cd3L(ClO4)(H2O)]ClO4·3H2O}n ( 2 ), and {[Cd6(L)2(NO3)2(CH3OH)(H2O)](NO3)2·2CH3OH·5H2O}n ( 3 ), were solvothermally constructed from a carboxylic functionalized bisazamacrocyclic ligand 4,4′-bis((4,7-bis(2-carboxyethyl)-1,4,7-triazacyclonon-1-yl)methyl)-1,1′-biphenyl (H4L). These compounds dispersed in ethanol show the multiple emissions originating from the monomeric and intramolecularly overlapping biphenyl moieties which could be sensitively quenched by picric acid (PA) and 4-nitrophenol (4-NP) through the effective fluorescence resonance energy transfer process. The differential fluorescent responses of each compound on exposure to PA and 4-NP individually make the convenient ratiometric discrimination of two analytes based on the fluorescent intensity ratio (I320/I360) attainable, and 1 and 2 as ratiometric chemosensors for PA present a broad linear detection range from 4 to 300 μM with detection limits of 0.84 and 0.93 μM, respectively. Furthermore, the blue light emission of 1 under an ultraviolet lamp could be selectively quenched by PA even in the presence of all other interfering nitroaromatic pollutants, which empowers the fast visual detection of PA by naked eye. 相似文献
75.
利用2,5-双(三氟甲基)对苯二甲酸(H2L)为主配体,氯化锌为金属盐,分别与辅助配体4,4''-联吡啶(4,4''-bipy)和2,2''-联吡啶(2,2''-bipy)通过溶剂热法反应合成了配合物[Zn(L)2(4,4''-bipy)(H2O)]n(1)和[Zn(L)(2,2''-bipy)]n(2)。通过X射线单晶衍射、红外光谱、元素分析、荧光光谱、热重分析等测试手段对其结构和性质进行了表征与研究。结果表明,配合物1是以Zn2+为金属节点,L2-和4,4''-bipy作为连接体相互连接,形成无限延伸的二维网状结构,层与层之间通过O5-H5B…O1氢键作用有序堆积形成三维结构。配合物2以Zn2+为金属节点,配体L2-上的每个羧基都通过双齿螯合的方式桥联锌离子并无限连接形成三维网状结构。 相似文献
76.
Dinuclear Cu(II) complexes based on p‐xylylene‐bridged bis(1,4,7‐triazacyclononane) ligands: Synthesis,characterization, DNA cleavage abilities and evaluation of superoxide dismutase‐ and catalase‐like activities 下载免费PDF全文
Three new dinuclear Cu(II) complexes with the formulas [Cu2(pxdmbtacn)Cl4] ( 1 ), [Cu2(pxdmbtacn)Cl0.7(NO3)1.3(OH)2(H2O)1.3]?6H2O ( 2 ) and [Cu2(pxdiprbtacn)Cl4] ( 3 ) together with one previously reported complex, [Cu2(pxbtacn)Cl4] ( 4 ), were obtained from Cu(II) salts with three p‐xylylene‐bridged bis‐tacn ligands bearing pendant alkyl substituents or without pendant group. Complex 2 was structurally characterized as a centrosymmetric dinuclear molecule with each metal center being coordinated to some labile ligands in addition to one tacn ring. Based on the results of mass spectrometry and UV–visible spectroscopy, complexes 1 and 3 are capable of existing in aqueous solution as dinuclear species but 4 can partially form a dimer of the original dinuclear motif. Complexes 1 , 3 and 4 can all effectively cleave supercoiled DNA oxidatively in the presence of hydrogen peroxide. The superoxide dismutase (SOD) activities of 1 and 3 measured under physiological conditions are comparable to that of the native CuZnSOD enzyme but the enzymatic activity of 4 is about three‐ to fourfold lower. Furthermore, complexes 1 , 3 and 4 demonstrate moderate scavenging effect on hydrogen peroxide and their catalase activities are in the decreasing order of 3 > 1 > 4 . 相似文献
77.
78.
Inside Back Cover: Stepwise Assembly of MII7 Clusters Revealed by Mass Spectrometry,EXAFS, and Crystallography (Chem. Eur. J. 51/2016) 下载免费PDF全文
79.
在不同酸度条件下(pH=3.0,6.0,7.4,9.0)诱导人血清白蛋白(HSA)进行质子化或去质子化,以研究其与小分子2,2',4,4',5,6'-六溴联苯醚(BDE154)的结合情况.首先将HSA与BDE154进行半柔性对接,发现BDE154与HSA周围的残基,如:酪氨酸150、赖氨酸195、赖氨酸199等存在较强的疏水相互作用.然后通过分子动力学模拟技术研究HSA在不同质子化状态下的动力学行为和热力学性质,可知过多的正电荷使HSA或者HSA-BDE154的系统稳定性变差.最后对HSA-BDE154的结合自由能进行预测,并对分子动力学模拟结果进行二级结构分析,结果表明HSA-BDE154复合物体系中随着酸度的增大,配体的结合对HSA的去螺旋过程有促进的作用. 相似文献
80.