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951.
952.
Yu-Hao Lee Tsun-Cheng Wu Chao-Wu Liaw Ten-Chin Wen Shih-Wei Feng Jey-Jau Lee Yao-Ting Wu Tzung-Fang Guo 《Organic Electronics》2013,14(4):1064-1072
This work studies a series of fluorescent materials, benzo[k]fluoranthene-based linear acenes, and uses these materials directly as the non-doped active layer to fabricate deep blue- to green-emissive organic light emitting diodes (OLEDs). Experimental results indicate that benzo[k]fluoranthene-based linear acenes with different substituents in pristine films have a wide range and strong intensity of the luminescence spectra. The substituents of benzo[k]fluoranthene derivatives modulate the lifetime of the excited state and PL spectra of excitonic, excimer or both emissions in the solid state. Controls of emission spectra are exploited in fabricating high-performance non-doped deep blue to green OLEDs with electroluminescence in the deep blue region (420–460 nm), green region (480–580 nm) or both (430–580 nm). 相似文献
953.
To simplify the assessment method of soy protein isolate(SPI) functionalities,the viscosity and functionalities of commercial SPI products were studied.Viscosity value(y) increases with increasing concentration(x) and exhibits a highly significant correlation with the exponential equation y = a·ebx.The b values of products are gradually enhanced from dispersion,emulsion and injected to gel type.Products with low b values(<0.2),and high dispersivity were dispersion-type.Products having high b values (>0.4) and gel springiness were gel-type.The other products with centered b value(0.2-0.4),high solubility and emulsifying capacity were emulsion-type. 相似文献
954.
Jin Liu Xianxue Wang Han Guo Xiaokang Shi Xiaoyu Ren Guosheng Huang 《Tetrahedron》2012,68(5):1560-1565
A novel NH4OAc/CuBr(PPh3)3-induced intermolecular Pummerer-type reaction between free (NH)-indoles and dimethylsulfoxide is first reported, which offers the 3-methylthiomethyl substituted indoles conveniently and efficiently. 相似文献
955.
The acyclic alkyl aromatic ketones, 2-isobutyl-4-methyl-1-arylpentan-1-one derivatives were designed and synthesized for photochemical investigations. Irradiation of such compounds in acetonitrile solution led to the Yang cyclization and Norrish type II cleavage photoproducts with a ratio of 1:1, whereas the reaction conducted in the solid state using the ionic chiral auxiliary method led to only the Yang cyclization product with as high as 99% ee. Furthermore, the conformational transitions were first observed in the reaction. 相似文献
956.
Hai Li Meng Zhou Qinghua Guo Renbiao Wu Jiangtao Xi 《Multidimensional Systems and Signal Processing》2018,29(2):719-732
An important issue in low-altitude wind-shear detection is to estimate the wind speed of wind field. In this paper, a novel method for wind speed estimation with airborne phased array radar is proposed by combining space time adaptive processing and compressive sensing. The proposed method is able to achieve accurate wind speed estimate in the condition of limited number of sampling pulses, as demonstrated by numerical examples. 相似文献
957.
A Hexagonal Covalent Porphyrin Framework as an Efficient Support for Gold Nanoparticles toward Catalytic Reduction of 4‐Nitrophenol
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Zheng‐Dong Ding Yu‐Xia Wang Sai‐Fei Xi Prof. Dr. Yunxing Li Prof. Dr. Zaijun Li Prof. Dr. Xuehong Ren Prof. Dr. Zhi‐Guo Gu 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(47):17029-17036
A hexagonal porphyrin‐based porous organic polymer, namely, CPF‐1, was constructed by 3+2 ketoenamine condensation of the C2‐symmetric porphyrin diamine 5,15‐bis(4‐aminophenyl)‐10,20‐diphenylporphyrin and 1,3,5‐triformylphloroglucinol. This material exhibits permanent porosity and excellent thermal and chemical stability. CPF‐1 can be employed as a superior supporting substrate to immobilize Au nanoparticles (NPs) as a result of the strong interactions between Au NPs and the CPF support. An Au@CPF‐1 hybrid was synthesized by an interfacial solution infiltration method with NaBH4 as reducing agent. Au NPs (5 nm) grew on CPF‐1 and were distributed without aggregation. Moreover, Au@CPF‐1 exhibits superior catalytic activity compared to many other reported Au‐based catalysts for the reduction of 4‐nitrophenol in the presence of NaBH4. In addition, Au@CPF‐1 has excellent stability and recyclability, and it can be reused for three successive reaction cycles without loss of activity. The dense distribution of phenyl rings on the channel walls of the CPF support can reasonably be regarded as the active sites that adsorb the 4‐nitrophenol molecule through hydrogen‐bonding and C?H ??? π interactions, as was confirmed by the X‐ray structure of model compound DAPP‐Benz. 相似文献
958.
Nonlinear Dynamics - This paper studies the formation–containment control problem for networked nonlinear Euler–Lagrange systems with input saturation. To realize the concurrency of... 相似文献
959.
This study contributes to international news flow literature methodologically, by significantly expanding its scope, and theoretically, by incorporating intermedia agenda-setting theory, through which we reveal how news media in different countries influence each other in covering international news. With a big data analysis of 4,708 online news sources from 67 countries in 2015, the study shows that wealthier countries not only continue to attract most of the world news attention, they are also more likely to decide how other countries perceive the world. However, international news flow is not as hierarchical and U.S.-centric as found earlier. Online-only, emerging media in core countries are not necessarily more impactful in setting the world news agenda than those in (semi)peripheral countries. 相似文献
960.