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151.
近年来亚硝酸甲酯分子(CHa0NO)的光解动力学研究十分活跃{‘5],主要集中在紫外激光的单光子解离的机理,光解过程的矢量相关性质和光解产物的态分布.CH30NO分子的解离能D。(CH30-NO)=174kJ·mol‘,若单从能量上看,人<689。的光就能使其解离,但人>400urn的光解离研究还未见报导.*H30*0分子在人>40onm的强激光场下是充电离还是先解离,是单光子解离还是多光子解离,以及通过哪个电子态解离都不清楚.时间飞行质谱不仅具有质量分辨率高、范围宽,而且响应快,因此适合做光解光电离过程初生态产物的探测.特别是时间飞… 相似文献
152.
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
153.
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
154.
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
155.
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