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151.
Xu QM Wang D Han MJ Wan LJ Bai CL 《Langmuir : the ACS journal of surfaces and colloids》2004,20(8):3006-3010
Scanning tunneling microscopy (STM) combined with cyclic voltammetry has been employed to investigate the adsorption of cinchonine on Cu(111). Similar to cinchonidine, cinchonine forms a long-range ordered adlayer with (4 x 4) symmetry on the substrate. The structural details on molecular adsorption were obtained by high-resolution STM images. On the basis of the previous results and obtained STM images, the quinoline ring is proposed to lie parallel to Cu(111) and serve as an anchoring group. The chiral quinuclidine moiety extends out of the surface to facilitate the interaction with the prochiral reactants. 相似文献
152.
Hierarchical and probabilistic quantum state sharing via a non-maximally entangled stateHierarchical and probabilistic quantum state sharing via a non-maximally entangled stateHierarchical and probabilistic quantum state sharing via a non-maximally entangled state 下载免费PDF全文
A scheme that probabilistically realizes hierarchical quantum state sharing of an arbitrary unknown qubit state with a four-qubit non-maximally entangled 丨X) state is presented in this paper. In the scheme, the sender Alice distributes a quantum secret with a Bell-state measurement and publishes her measurement outcomes via a classical channel to three agents who are divided into two grades. One agent is in the upper grade, while the other two agents are in the lower grade. Then by introducing an ancillary qubit, the agent of the upper grade only needs the assistance of any one of the other two agents for probabilistically obtaining the secret, while an agent of the lower grade needs the help of both the other two agents by using a controlled-NOT operation and a proper positive operator-valued measurement instead of the usual projective measurement. In other words, the agents of two different grades have different authorities to reconstruct Alice's secret in a probabilistic manner. The scheme can also be modified to implement the threshold-controlled teleportation. 相似文献
153.
Xiaolong Shi Xiaoru Zhao Libing Duan Huinan Sun Jinming Liu Xiaojun Bai Mengmeng Guan Mengmeng Cao Jinru Liu 《Journal of Sol-Gel Science and Technology》2013,66(2):301-305
Sn-doped ZnO (SZO) thin films are deposited by sol–gel dip-coating method with Sn content at 0 at.% and 1–15 at.% with an increment of 2 at.%. The structure and luminescence of the films are investigated. X-ray diffraction results indicate that all the SZO samples show preferential orientation along the (002) direction, and the scanning electron microscope exhibits that the surface morphology of the films change from nanoparticles to nanorods with increasing Sn concentration. X-ray photoelectron spectroscopy reveals that Sn exists as valence of +4 in the matrix. The photoluminescence peaks at 381 and 398 nm are observed in all the samples. The ratio of intensity of peak at 381 nm to that of peak at 398 nm differed markedly. The intensity of peak at 398 nm might be due to the response for the Sn atoms, while the intensity of peak at 381 nm is probably related to the quantum size effect. 相似文献
154.
Guangping Wan Hongjun Xia Jun Wang Jiawei Liu Botao Song Ying Yang Quan Bai 《中国化学快报》2018,29(1):213-216
The monodisperse superficially porous core-shell silica microspheres (CSSMs) with controllable shell thickness and pore size were synthesized by an improved polymerization-induced colloid aggregation (PICA) approach for fast separation of small solutes and proteins. 相似文献
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As the hardware of FLIM technique becomes mature, the most important criterion for FLIM application is the correct interpretation of its data. In this research, first of all, a more orthogonal phasor approach, called as Modified Phasor Approach (MPA), is put forward. It is a way to calculate the lifetime of the complex fluorescent process, and a rule to measure how much the fluorescence process deviates from single exponential decay. Secondly, MPA is used to analysis the time-resolved fluorescence processes of the transfected CHO-K1 Cell lines expressing adenosine receptor A1R tagged by CYP and YFP, measured in the channel of the acceptor. The image of the fluorescence lifetime and the multiplication of the fluorescence lifetime and deviation from single exponential decay reveal the details of the Homo-FRET. In one word, MPA provides the physical meaning in its whole modified phasor space, and broadens the way for the application of the fluorescence lifetime imaging. 相似文献
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Tunable and Specific Formation of C@NiCoP Peapods with Enhanced HER Activity and Lithium Storage Performance 下载免费PDF全文
Yuanjuan Bai Dr. Huijuan Zhang Li Liu Haitao Xu Prof. Dr. Yu Wang 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(3):1021-1029
The superior properties of nanomaterials with a special structure can provide prospects for highly efficient water splitting and lithium storage. Herein, we fabricated a series of peapodlike C@Ni2?xCoxP (x≤1) nanocomposites by an anion‐exchange pathway. The experimental results indicated that the HER activity of C@Ni2?xCoxP catalyst is strongly related to the Co/Ni ratio, and the C@NiCoP got the highest HER activity with low onset potential of ~45 mV, small Tafel slope of ~43 mV dec?1, large exchange current density of 0.21 mA cm?2, and high long‐term durability (60 h) in 0.5 m H2SO4 solutions. Equally importantly, as an anode electrode for lithium batteries, this peapodlike C@NiCoP nanocomposite gives excellent charge–discharge properties (e.g., specific capacity of 670 mAh g?1 at 0.2 A g?1 after 350 cycles, and a reversible capacity of 405 mAh g?1 at a high current rate of 10 A g?1). The outstanding performance of C@NiCoP in HER and LIBs could be attributed to the synergistic effect of the rational design of peapodlike nanostructures and the introduction of Co element. 相似文献