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排序方式: 共有206条查询结果,搜索用时 15 毫秒
1.
The(3+1)-dimensional Burgers equation, which describes nonlinear waves in turbulence and the interface dynamics,is considered. Two types of semi-rational solutions, namely, the lump–kink solution and the lump–two kinks solution, are constructed from the quadratic function ansatz. Some interesting features of interactions between lumps and other solitons are revealed analytically and shown graphically, such as fusion and fission processes. 相似文献
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Nonlinear Dynamics - Conventional tuned liquid column dampers (TLCDs) are deficient in multidirectionality. In contrast, toroidal TLCDs are designed to extend the application to multidirectional... 相似文献
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Zhi-Chao Liu Jian-Wen QiChun Hu Li ZhangWei Song Ru-Ping LiangJian-Ding Qiu 《Analytica chimica acta》2015
Copper is a highly toxic environmental pollutant with bioaccumulative properties. Therefore, sensitive detection of Cu2+ is very important to prevent over-ingestion, and visual detection is preferred for practical applications. In this work, we developed a simple and environmental friendly approach to synthesize hyperbranched polyethyleneimine-protected copper nanoclusters (hPEI-Cu NCs) with great stability against extreme pH, high ionic strength, thiols etching and light illumination, which were then conjugated to the surface of silica coated CdSe quantum dots (QDs) to design a ratiometric fluorescence probe. In the presence of different amounts of Cu2+ ions, the fluorescence of Cu NCs can be drastically quenched, while the emission from QDs stayed constant to serve as a reference signal and the color of the probe changed from yellow-green to red, resulting in ratiometric and visualization detection of Cu2+ ion with high accuracy. The detection limit for Cu2+ was estimated to be 8.9 nM, much lower than the allowable level of Cu2+ in drinking water (∼20 μM) set by U.S. Environmental Protection Agency. Additionally, this probe can be also applied for the determination of Cu2+ ion in complex real water samples. 相似文献
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Jian-Wen ShiHao-Jie Cui Jian-Wei ChenMing-Lai Fu Bin XuHong-Yuan Luo Zhi-Long Ye 《Journal of colloid and interface science》2012,388(1):201-208
In order to more easily separate TiO2 photocatalyst from the treated wastewater, TiO2 film was immobilized on the surface of activated carbon fibers (ACFs) by employing two kinds of coating procedures, dip-coating, and hydrothermal treatment. The effects of coating procedures on microstructure of TiO2-coated ACFs (TiO2/ACFs), such as morphology, porous property, crystal structure, and light absorption characteristics were investigated in detail. The adhesion property between TiO2 film and ACFs was evaluated by ultrasonic vibration, and the photocatalytic activity of TiO2/ACFs was tested by the photocatalytic decoloration of methylene blue solution. The results show that hydrothermal treatment presented many advantages to obtain high-performance TiO2/ACFs photocatalyst in comparison with dip-coating. Hydrothermal treatment could improve the binding property between TiO2 films and ACFs, which endowed the as-obtained TiO2/ACFs photocatalyst with improved reusable performance, and TiO2/ACFs synthesized by hydrothermal treatment presented higher photocatalytic activity. 相似文献
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Hydrothermal reactions of rare earth oxides with racemic tartaric acid (H2tar) yielded 7 rare earth(III) MOFs with general formulas [R2(tar)3(H2O)2]n (R=Y (1), Sm (4), Eu (5), Tb (6), Dy (7)) and [R2(tar)2(C2O4)(H2O)2]n·4nH2O (R=La (2), Nd (3)). X-ray powder diffraction analysis and single-crystal X-ray diffraction analysis reveal that they present two different structural types. MOFs 1, 4, 5, 6 and 7 are isostructural and crystallize in the orthorhombic non-centrosymmetric space group Iba2, and feature unusual fsc-3,4-Iba2 topology. MOFs 2 and 3 are isostructural and crystallize in monoclinic P21/c space group and display rare fsx-4,5-P21/c topology containing hydrophilic channels bounded by triple helical chains along a axis. MOFs 3, 4, 5, 6 and 7 exhibit intense lanthanide characteristic photoluminescence at room temperature. 相似文献
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Qiang Zhou Ming-Lai Fu Bao-Ling Yuan Hao-Jie Cui Jian-Wen Shi 《Journal of nanoparticle research》2011,13(12):6661-6672
The semiconductor quantum dots (QDs) can be very efficient to tune the response of photocatalyst of TiO2 to visible light. In this study, CdS QDs formed in situ with about 8 nm have been successfully deposited onto the surfaces
of TiO2 nanotubes (TNTs) to form TNTs/CdS QDs nanocomposites by use of a simple bifunctional organic linker, thiolactic acid. The
diffuse reflectance spectroscopy (DRS) spectra of as prepared samples showed that the absorption edge of the TNTs/CdS composite
is extended to visible range, with absorption edge at 530 nm. The photocatalytic activity and stability of TNTs/CdS were also
evaluated for the photodegradation of rhodamine B. The results showed that when TNTs/CdS QDs was used, photocatalytic degradation
of RhB under visible light irradiation reached 91.6%, higher than 45.4 and 30.5% for P25 and TNTs, respectively. This study
indicated that the TNTs/CdS QDs nanocomposites were superior catalysts for photodegradation under visible light irradiation
compared with TNTs and P25 samples, which may find wide application as a powerful photocatalyst in environmental field. 相似文献