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111.
The novel (S)-BINOL-based sensor 1 incorporating triazole moieties could be obtained by click reaction. The results show that 1 can exhibit excellent fluorescence response behaviors toward Hg2+ (selective switching-off) and Ag+ (selective switching-on) without interference from other metal ions, which functions as a molecular switch. This work can expand the application of click reaction in design and synthesis of the novel fluorescence sensor molecules. 相似文献
112.
Two coumarin salen-based sensors CS1 and CS2 can exhibit a pronounced fluorescence enhancement response toward Mg(2+) as high as 36-fold (CS1) and 111-fold (CS2) in the presence of Na(+) as a synergic trigger. More importantly, the fluorescent color of CS1 was bright green instead of weak yellow after the addition of Mg(2+) and Na(+) together, which can be easily detected by the naked eye. 相似文献
113.
Zhitao Xing Hui‐Chen Wang Prof. Dr. Yixiang Cheng Prof. Dr. Tony D. James Prof. Dr. Chengjian Zhu 《化学:亚洲杂志》2011,6(11):3054-3058
Two boron‐contained fluorescent sensors, 1 and 2 , based on coumarin have been prepared. The fluorescence response of the two systems was investigated with addition of saccharide and mercury ions. Sensor 2 behaves as a bifunctional fluorescent switch with chemical inputs of D ‐fructose and mercury ions. 相似文献
114.
Zhang M Yang H Zhang Y Zhu C Li W Cheng Y Hu H 《Chemical communications (Cambridge, England)》2011,47(23):6605-6607
The direct reductive amination of aromatic aldehydes has been achieved with excellent isolated yields (89-96%) using readily accessible Ph(3)PAuCl/AgOTf catalyst along with ethyl Hantzsch ester as hydrogen source under mild reaction conditions. 相似文献
115.
We discuss the wavelet transform profilometry based on the continuous wavelet transform technique as viewed from frequency analysis. We deduce the expression of one-dimensional (1-D) and two-dimensional (2-D) wavelet transform in frequency domain and analyze their characteristics in the application of demodulating the fringe patterns. We also compare 1-D CWT and 2-D CWT in demodulating the oblique fringe patterns with dual carrier frequency components. When oblique fringe patterns are processed, the direction normal to the grating line and x axis or y axis is not identical. By 1-D CWT, in which wavelet transform is carried out row by row, we cannot obtain the most similarity between local signal and the wavelet functions with different dilation values. While a fan 2-D continuous wavelet transformation can deal with the fringe pattern as a 2-D unit as well as has multi-directions, its advantage is that it can be used to exact the information in the spatial direction. However, its spatial localization ability is not very good, which leads that it is not suitable for demodulating the fringe patterns with high phase variation. Computer simulations and experiments have verified our analysis. 相似文献
116.
We discuss the structure condition and sampling condition of wavelet transform profilometry (WTP) based on dual-frequency fringe pattern in this work. In the mentioned method a grating fringe with dual-frequency components is projected onto an object. And two wavelet ridge lines can be extracted by means of wavelet analysis, from which we can calculate two groups of wrapped phase information. Afterwards the retrieved phase with higher precision can be obtained through phase unwrapping process. However, it should be noted that the spectral aliasing of the deformed fringe pattern must be avoided in order to restore the correct phase information. And the two fringe carrier frequencies have to obey some rules as well. In this paper, the structure condition and sampling condition of the proposed method is deduced from the point of view of frequency analysis. It is proven that there would be no frequency overlapping in the deformed fringe pattern only when both of the two conditions mentioned previously are fulfilled. The results of computer simulations and experiments verify the validity of our theory. 相似文献
117.
Shuwei Zhang Yuan Sheng Guo Wei Yiwu Quan Yixiang Cheng Chengjian Zhu 《Journal of polymer science. Part A, Polymer chemistry》2014,52(12):1686-1692
A novel conjugated polymer P‐1 incorporating Ru(II) bis(acetylide) complex and borondipyrromethene (BODIPY) moieties in the main chain was synthesized by Pd‐catalyzed Sonogashira coupling reaction of diethynyl substituted BODIPY derivative ( M‐1 ) and Ru(II) bis(acetylide) complex ( M‐2 ), and the reference polymer P‐2 was obtained from the same method as preparation of P‐1 . Compared with P‐2 , Ru(II)‐containing polymer P‐1 shows low‐bandgap as 0.87 eV from cyclic voltammetry, and obvious redshifts in both UV–vis absorption and fluorescence spectra. © 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2014 , 52, 1686–1692 相似文献
118.
§1. IntroductionThepurposeofDomainstheory(introducedbyD.Scott)istomodelthedenotationalse-manticsofcomputerprogrammonglanguages[1].Animportantframe-workforthedenota-tionalsemanticsofprogramminglanguagesisthecategoryofL-domainswithstablefunctions.L-dom… 相似文献
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