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21.
Rapid and Efficient Separation of Oil from Oil‐in‐Water Emulsions Using a Janus Cotton Fabric
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Zijie Wang Yu Wang Prof. Dr. Guojun Liu 《Angewandte Chemie (International ed. in English)》2016,55(4):1291-1294
A novel bi‐functional Janus cotton fabric is used to separate oil from oil‐in‐water emulsions. This fabric is superhydrophobic on one surface and polyamine‐bearing on the other. When used as a filter, the polyamine‐bearing side causes the micrometer‐sized oil droplets to coalesce. The coalesced oil then fills fabric pores on the superhydrophobic side and selectively permeates it. Oil separation using this method is rapid and the separated oil is pure. Furthermore, the content of the model oil hexadecane (HD) in water after a separation can be reduced to less than 0.03±0.03 vol %. These features demonstrate the practical potential of this technology. 相似文献
22.
Gregory W. Peterson John J. Mahle Jared B. DeCoste Wesley O. Gordon Joseph A. Rossin 《Angewandte Chemie (International ed. in English)》2016,55(21):6235-6238
Here we discuss the removal of nitrogen dioxide, an important toxic industrial chemical and pollutant, from air using the MOF UiO‐66‐NH2. The amine group is found to substantially aid in the removal, resulting in unprecedented removal capacities upwards of 1.4 g of NO2 /g of MOF. Furthermore, whereas NO2 typically generates substantial quantities of NO on sorbents, the amount generated by UiO‐66‐NH2 is significantly reduced. Of particular significance is the formation of a diazonium ion on the aromatic ring of the MOF, and the potential reduction of NO2 to molecular nitrogen. 相似文献
23.
以碱溶法制备的高孔隙度硅胶为基质,与γ-环氧丙基丙氧基三甲氧基硅烷配基进行共价键合,经过酸性水解,使其转化为二醇基,制成了高效亲水凝胶色谱填料。键合反应中采用70 ℃回流冷凝管,使生成的甲醇可顺利地排到体系外,促使反应向有利于键合的方向进行,以获得较高的配基密度。研究表明,水解反应条件与配基密度以及柱效密切相关。当配基密度为2.6~3.5 μmol/m2时,才能显示出较高的柱效。蛋白质分离实验结果显示,此填料的相对分子质量排阻极限为300000,牛血清白蛋白的回收率为99%。 相似文献
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The polytropic filtration equation with generalized Fisher–KPP sources is considered. We will show that the equation may have finite times oscillatory traveling waves, and try to give a complete classification by virtue of a singular exponent in the source according to the finiteness of the oscillatory times of traveling waves. 相似文献
26.
A new family of finite-dimensional simple modular Lie superalgebra ? is constructed based on results of Y. Z. Zhang and Q. C. Zhang [J. Algebra, 2009, 321: 3601–3619]. The simplicity and generators of ? are discussed and the derivation superalgebra of ? is characterized. Furthermore, the invariance of the nonnatural filtration of ? is determined by the method of minimal dimension of image spaces. 相似文献
27.
Wei Zhang 《中国科学 数学(英文版)》2014,57(8):1657-1670
We consider the gradient flow of the Yang-Mills-Higgs functional of twist Higgs pairs on a Hermitian vector bundle(E,H)over Riemann surface X.It is already known the gradient flow with initial data(A0,φ0)converges to a critical point(A∞,φ∞).Using a modified Chern-Weil type inequality,we prove that the limiting twist Higgs bundle(E,d′′A∞,φ∞)coincides with the graded twist Higgs bundle defined by the HarderNarasimhan-Seshadri filtration of the initial twist Higgs bundle(E,d′′A0,φ0),generalizing Wilkin’s results for untwist Higgs bundle. 相似文献
28.
Conjunctive modelling of free/porous flows provides a powerful and cost‐effective tool for designing industrial filters used in the process industry and also for quantifying surface–subsurface flow interactions, which play a significant role in urban flooding mechanisms resulting from sea‐level rise and climate changes. A number of well‐established schemes are available in the literature for simulation of such regimes; however, three‐dimensional (3D) modelling of such flow systems still presents numerical and practical challenges. This paper presents the development of a fully 3D, transient finite element model for the prediction and quantitative analyses of the hydrodynamic behaviour encountered in industrial filtrations and environmental flows represented by coupled flows. The weak‐variational formulation in this model is based on the use of C0 continuous equal‐order Lagrange polynomial functions for velocity and pressure fields represented by 3D hexahedral finite elements. A mixed UVWP finite element scheme based on the standard Galerkin technique satisfying the Ladyzhenskaya–Babuska–Brezzi stability criterion through incorporation of an artificial compressibility term in the continuity equation has been employed for the solution of coupled partial differential equations. We prove that the discretization generates unified stabilization for both the Navier–Stokes and Darcy equations and preserves the geometrical flexibility of the computational grids. A direct node‐linking procedure involving the rearrangement of the global stiffness matrix for the interface elements has been developed by the authors, which is utilized to couple the governing equations in a single model. A variety of numerical tests are conducted, indicating that the model is capable of yielding theoretically expected and accurate results for free, porous and coupled free/porous problems encountered in industrial and environmental engineering problems representing complex filtration (dead‐end and cross‐flow) and interacting surface–subsurface flows. The model is computationally cost‐effective, robust, reliable and easily implementable for practical design of filtration equipments, investigation of land use for water resource availability and assessment of the impacts of climatic variations on environmental catastrophes (i.e. coastal and urban floods). The model developed in this work results from the extension of a multi‐disciplinary project (AEROFIL) primarily sponsored by the European aerospace industries for development of a computer simulation package (Aircraft Cartridge Filter Analysis Modelling Program), which was successfully utilized and deployed for designing hydraulic dead‐end filters used in Airbus A380.Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
29.
本文应用象空间极小维数的方法研究了Cartan型模李超代数HO的非平凡可迁滤过(HO,R)的不变性.应用滤过的不变性得到模李超代数HO的某些内蕴性质,从而得到此类李超代数在同构意义下的分类. 相似文献
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