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11.
Tai Y Wang L Gao J Amer WA Ding W Yu H 《Journal of colloid and interface science》2011,360(2):731-738
A simple strategy to fabricate magnetic porous microspheres of Fe(3)O(4)@poly(methylmethacrylate-co-divinylbenzene) was demonstrated. The magnetic microspheres, consisting of polymer-coated iron oxide nanoparticles, were synthesized by the modified suspension polymerization of methacrylate and divinylbenzene in the presence of a magnetic fluid. The morphology and the properties of the magnetic porous microspheres were examined by scanning electron microscopy, transmission electron microscopy, superconducting quantum interference device, Fourier transform infrared spectroscopy, thermogravimetry, and X-ray powder diffraction. The pore size distribution and the specific surface area of the microspheres were measured by nitrogen sorption and mercury porosimetry technique. As predicted from the previous knowledge, the magnetic porous microspheres possessed a high specific surface area using n-hexane as a porogen. It was further found that the amounts of divinylbenzene and methacrylate, the ratio of porogens, and the dosage of ferrofluids affect the specific surface area of the microspheres. Furthermore, the microspheres were applied to remove phenol from aqueous solutions. The results showed that the microspheres had a high adsorption capacity for phenol and a high separation efficiency due to their porous structure, polar groups, and superparamagnetic characteristic. 相似文献
12.
A new approach to realize high-energy and high-power stimulated Brillouin scattering phase conjugation mirrors (SBS-PCMs) is described.The reflectivity of SBS-PCM is investigated under a 10-Hz repetition rate and a high energy load.The relationship between reflectivity and input energy is examined experimentally with different PCM structures,focus lengths,and medium cell structures.A medium cell with a circulating structure is designed,and its advantage is demonstrated through an experimental comparison with traditional PCM structures.The 30-cm focus lens and 150-cm collimation lens are optimized when the input energy reaches 1010 mJ at 10-Hz repetition rate.Therefore,a reflectivity of 84.7% and a higher energy load using the circulating two-cell structure are achieved. 相似文献
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Nonlinear Dynamics - An integrable extension of the Kadomtsev–Petviashvili (KP) and Davey–Stewartson (DS) equations is investigated in this paper. We will refer to this integrable... 相似文献
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Wanquan Jiang Yingqiang Sun Yulei Xu Chao Peng Xinglong Gong Zhong Zhang 《Rheologica Acta》2010,49(11-12):1157-1163
The rheological behavior of polymethylmethacrylate (PMMA) particles suspensions in glycerine–water mixtures has been investigated by means of steady and dynamic rheometry in this work. The shear rheology of these suspensions demonstrates a strong shear thickening behavior. The variations of shear viscosity with the volume fraction and ratios of glycerine to water are discussed. The effect of volume fraction can be qualitatively explained using a clustering mechanism, which attributes the phenomena to the formation of temporary, hydrodynamic clusters. The influence of interactions between glycerine–water mixtures and PMMA particles on shear thickening is investigated by varying the ratio of glycerine to water. In addition, the reversible and thixotropic properties of suspensions of PMMA dispersed in glycerine–water (3:1) mixtures are also investigated, and the results demonstrate the excellent reversible and thixotropic properties of PMMA particle suspensions. 相似文献
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Min Zhang Yulei Jia Jianhua Cao Guanghui Li Huacheng Ren Hui Li 《Green Chemistry Letters and Reviews》2018,11(4):379-386
In this study, the fluorescent carbon dots (CDs) of good biocompatibility and low toxicity was prepared by a carbonation route, and a strong enhancement effect of CDs on the luminol-K3Fe(CN)6 chemiluminescence (CL) system was observed. 5?±?1?nm CDs were used as catalysts to enhance the reaction sensitivity. In the presence of 2-methoxyestradiol (2-ME), the CL intensity of CDs-luminol-K3Fe(CN)6 was significantly inhibited. The relative CL intensity was linearly related to the 2-ME concentration in the range of 1.0?×?10?9 –1.0?×?10?7?g?mL-1 with a lower detection limit of 4.1?×?10?10?g?mL?1. As a preliminary application, the highly sensitive method was successfully applied to the determination of 2-ME in both pharmaceutical preparation and serum samples with satisfactory results. The possible mechanism of CL reaction catalyzed by CDs was investigated and the CDs played a role of catalyst in the reaction which could promote the generation of oxygen radicals.It could be concluded that the enhancement effect on CL by CDs was attributed to the formation of oxygen radicals. The oxidation reaction of luminol was accelerated by oxygen radicals, which led to the enhanced CL emission. 相似文献
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用顶部籽晶熔融织构法(TSMTG)制备了30min直径的YBCO超导块,研究了不同的工艺条件对样品宏观形貌、织构取向和磁浮力的影响,比较了3种样品在零场冷条件下的排斥力和场冷条件下的吸引力。结果发现:由籽晶控制取向生长的单畴YBCO样品宏观形貌是以顶部籽晶为中心的4个结晶扇区,有单一的c轴取向,零场冷条件下的排斥力和场冷条件下的吸引力最大;籽晶成核但没有控制取向生长的YB-CO样品宏观形貌是以顶部籽晶为中心的多个(大于4个)扇区,相邻扇区间夹角不等,c轴取向不一致,磁浮力性能居中;非籽晶成核生长的多畴YBCO样品,上表面是以籽晶为中心的一个边长约1cm的四方结晶区,其余部分是自发成核的多晶,样品c轴取向杂乱,磁浮力很低。 相似文献
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Abid M. Amin Li Wang Haojie Yu Wael A. Amer Jingmin Gao Tai Yulei 《高分子科学杂志,A辑:纯化学与应用化学》2013,50(11):937-946
Polydichlorophosphazenes (PDCP) were synthesized through ring opening polymerization of hexachlorocyclotriphosphazene (HCCP). The polymerization behavior of HCCP under varying conditions of time and amount of catalyst was investigated. The chlorine atoms in polydichlorophosphazenes (PDCP) were substituted with p-oxybenzaldehyde and (or) diethylamine to synthesize poly[bis(p-oxybenzaldehyde diethylamino)phosphazenes](PPOBADEAP), poly[bis(p-oxybenzaldehyde)phosphazenes] (PPOBAP) and poly[bis(diethyl amino) phosphazenes] (PDEAP). The supporting evidence for the success of this synthesis was provided by nuclear magnetic resonance (1H-NMR, and 31P-NMR), gel permeation chromatography (GPC), and energy-dispersive X-ray spectroscopy (EDAX). The self-assembly behavior of PPOBADEAP, PPOBAP and PDEAP was observed in different solvents by the same concentration of polymers. The optical microscopy, scanning electron microscopy (SEM) and transmission electron microscopy (TEM) images indicated that PPOBADEAP formed various morphologies in different solvents while PPOBAP and PDEAP did not show self-assembly behavior at the same conditions. 相似文献