2,3,4,5‐Tetraphenylsilole‐Based Conjugated Polymers: Synthesis,Optical Properties,and as Sensors for Explosive Compounds

A series of linear 2,5‐tetraphenylsilole‐vinylene‐type polymers were successfully synthesized for the first time. The tetraphenylsilole moieties were linked at their 2,5‐positions through a vinylene bridge with p‐dialkoxybenzenes to obtain polymer PSVB and with 3,6‐carbazole to obtain polymer PSVC . For comparison, 2,5‐tetraphenylsilole‐ethyne‐type polymer PSEB was also synthesized, in which the vinylene bridge of PSVB was replaced with an ethyne bridge. Very interestingly, the bridging group (vinylene or ethyne) had a significant effect on the photophysical properties of the corresponding polymers. The fluorescence peak of PSEB at 504 nm in solution originated from the emission of its silole moieties, whereas PSVB and PSVC emitted yellow light and no blueish–green emission from the silole moieties was observed, thus demonstrating that the emissions of PSVB and PSVC were due to their polymer backbones. More importantly, the 2,5‐tetraphenylsilole‐ethyne polymer exhibited a pronounced aggregation‐enhanced emission (AEE) effect but the 2,5‐tetraphenylsilole‐vinylene polymer was AEE‐inactive. Moreover, both AEE‐active 2,5‐tetraphenylsilole‐ethyne polymer and AEE‐inactive 2,5‐tetraphenylsilole‐vinylene polymers were successfully applied as fluorescent chemosensors for the detection of explosive compounds.     

Graphene preparation and process parameters by pre-intercalation assisted electrochemical exfoliation of graphite

Journal of Solid State Electrochemistry - Among all the preparation methods, electrochemical exfoliation of graphite in neutral aqueous solution to prepare high-quality graphene is a hot research...     

A geometric correction based robust color image watermarking scheme using quaternion Exponent moments

Most of the existing color image watermarking schemes was designed to mark grayscale images or use the color components, which ignore the significant correlation between different color channels. Recently, several approaches were developed to process the color channels intrinsically, but they always cannot counterattack geometric distortions. It is a challenging work to design a robust color image watermarking scheme against geometrical distortions. In this paper, we propose a geometric correction based robust color image watermarking approach using quaternion Exponent moments (QEMs). The novelty of our approach is that (1) the QEMs are derived to deal with the color images in a holistic manner, and (2) the QEMs are exploited for estimating the geometric distortions parameters in order to permit watermark extraction. Experimental results confirm the validity of our approach and its higher robustness against geometrical distortions compared to alternative watermarking methods in the literature.     

V2O5 nanobelt-carbonized bacterial cellulose composite with enhanced electrochemical performance for aqueous supercapacitors

Journal of Solid State Electrochemistry - V2O5 nanobelt-carbonized bacterial cellulose (V2O5-CBC) nanocomposite was synthesized via a hydrothermal process in a single step. The prepared samples...     

Mapping some basic functions and operations to multilayer feedforward neural networks for modeling nonlinear dynamical systems and beyond

Nonlinear Dynamics - This study significantly extends the development of an initialization methodology for designing multilayer feedforward neural networks, aimed primarily at modeling nonlinear...     

软件可靠性中NHPP模型趋势检验的U-图方法

对软件可靠性中一类重要的模型——非齐次泊松过程（ＮＨＰＰ）模型的趋势检验，构造了一列检验的统计量，独立同分布于均匀分布Ｕ（０，１）．并由柯尔莫哥洛夫检验判定所选择的可靠性增长趋势模型的合适性．本文方法可适用于完全数据和不完全数据．这里报告的方法，可以作为选择软件可靠性模型时的一种判断依据，以定量地评判选择的软件可靠性模型的优劣．     

Synthesis and cytotoxic activity of heterocycle-substituted phthalimide derivatives

<正>A series of heterocycle-substituted phthalimide derivatives were synthesized.Structurally diverse derivatives with heterocyclic rings,including furan,imidazo[1,2-a]pyridine,1,3,4-thiadiazine,imidazo[2,1-b][1,3,4]thiadiazine,pyrazole,1,2,4-triazolo[3,4- b][1,3,4]thiadiazine,thiazole and thiazoline,were obtained by the reactions ofα-bromoketone intermediate with various nucleophiles containing oxygen,nitrogen and sulfur atom.Their cytotoxic activity was also evaluated against five human cancer cell lines in vitro.