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排序方式: 共有357条查询结果,搜索用时 15 毫秒
151.
We define the set of double complemented elements in BL‐algebras and state and prove some theorems which determines properties of these sets. We introduce the notion of an almost top element and study the properties of these elements (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
152.
Hedieh Pazokian Mahmoud Mollabashi Alexandros Selimis Emmanuel Stratakis Jalal Barzin Saeid Jelvani 《Applied Physics A: Materials Science & Processing》2013,110(3):633-637
KrF laser processing of polyethersulfone (PES) films at three different pulse durations regarding to the change in biocompatibility is presented with cell culture study. Various microstructure and chemistry results were obtained on the surface upon laser irradiation. It is shown that nanoscale hydrophilic ripples significantly affect the adhesion of L929 cells on the surface. 相似文献
153.
In electroporation, applied electric field creates hydrophilic nanopores in a cell membrane that can serve as a pathway for inserting biological samples to the cell. It is highly desirable to understand the ionic transfer and fluid flow through the nanopores in order to control and improve the cell transfection. Because of submicron dimensions, conventional theories of electrokinetics may lose their applicability in such nanopores. In the current study, the Poisson-Nernst-Planck equations along with modified Navier-Stokes equations and the continuity equation are solved in order to find electric potential, fluid flow, and ionic concentration through the nanopores. The results show that the electric potential, velocity field, and ionic concentration vary with the size of the nanopores and are different through the nanopores located at the front and backside of the cell membrane. However, on a given side of the cell membrane, angular position of nanopores has fewer influences on liquid flow and ionic transfer. By increasing the radius of the nanopores, the averaged velocity and ionic concentration through the nanopores are increased. It is also shown that, in the presence of electric pulse, electrokinetic effects (electroosmosis and electrophoresis) have significant influences on ionic mass transfer through the nanopores, while the effect of diffusion on ionic mass flux is negligible in comparison with electrokinetics. Increasing the radius of the nanopores intensifies the effect of convection (electroosmosis) in comparison with electrophoresis on ionic flux. 相似文献
154.
Abbas Ali Esmaeili Saeid Amini GhalandarabadMahdieh Zangouei 《Tetrahedron letters》2012,53(42):5605-5607
In the presence of 4 Å molecular sieves in CH3CN, a process for the cyanobenzoylation and cyanocarbonylation of isatins with benzoycyanides and ethylcyanoformate under mild reaction conditions has been developed. This approach provides easy access to a wide range of 3-cyano-3-benzoyloxyoxindoles and 3-cyano-3-ethoxycarbonyloxyoxindoles in good to excellent yields. 相似文献
155.
The heteronuclear Bi[Fe(CN)6]·5H2O complex was synthesized and single-phase perovskite-type BiFeO3 nanoparticles with an average size of 30 nm were obtained by its decomposition at 600 °C. The complex and its decomposition products were analyzed using elemental analysis, thermal analysis (TGA/DTA/DSC), X-ray diffraction (XRD), Fourier-transformed infrared spectroscopy (FT-IR), UV–Vis spectroscopy, BET specific surface area measurement, scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS) and magnetic measurements. The magnetic measurement confirms that the product shows a ferromagnetic order at room temperature, which may be ascribed to the size confinement effect. The DTA and DSC results confirm the multiferroic nature of the BiFeO3 nanoparticles with Neel and Curie points at 372 and 825 °C, respectively. The BiFeO3 prepared by this method could be an appropriate visible-light photocatalytic material due to its strong absorption band in the visible region. This method is simple, low-cost, safe and also suitable for industrial production of high purity perovskite-type BiFeO3 nanoparticles for electromagnetic applications. 相似文献
156.
Saeid Vafaei 《Advances in colloid and interface science》2010,159(1):72-291
This paper begins with an extensive review of the formation of gas bubbles, with a particular focus on the dynamics of triple lines, in a pure liquid and progresses into an experimental study of bubble formation on a micrometer-sized nozzle immersed in a quiescent pool of aqueous gold nanofluid. Unlike previous studies of triple line dynamics in a nanofluid under evaporation or boiling conditions, which are mainly caused by the solid surface modification due to particle sedimentation, this work focuses on the roles of nanoparticles suspended in the liquid phase. The experiments are conducted under a wide range of flow rates and nanoparticle concentrations, and many interesting phenomena are revealed. It is observed that nanofluids prevent the spreading of the triple line during bubble formation, i.e. the triple line is pinned somewhere around the middle of the tube wall during the rapid bubble formation stage whereas it spreads to the outer edge of the tube for pure water. A unique ‘stick-slip’ movement of the triple line is also observed for bubbles forming in nanofluids. At a given bubble volume, the radius of the contact line is found to be smaller for higher particle concentrations, but a reverse trend is found for the dynamic bubble contact angle. With the increase of particle concentration, the bubble frequency is raised and the bubble departure volume is decreased. The bubble shape is found to be in a good agreement with the prediction from Young-Laplace equation for given flow rates. The influence of nanoparticles on other detailed characteristics related to bubble growth inside, including the variation of bubble volume expansion rate, the radius of the curvature at the apex, the bubble height and bubble volume, is revealed. It is suggested that the variation of surface tensions and the resultant force balance at the triple line might be responsible for the modified dynamics of the triple line. 相似文献
157.
Let \({\mathcal{S}}\) be a locally compact semigroup and \(L_{0}^{\infty}({\mathcal{S}},M_{a}({\mathcal{S}}))\) be the Banach space of all μ-measurable (\(\mu\in M_{a}({\mathcal{S}})\)) functions vanishing at infinity, where \(M_{a}({\mathcal{S}})\) denotes the algebra of all measures with continuous translations. Recently, we have shown that \(L_{0}^{\infty}({\mathcal{S}},M_{a}({\mathcal{S}}))^{*}\) can be equipped with an Arens type product. Here, we show that the topological center of \(L_{0}^{\infty}({\mathcal{S}},M_{a}({\mathcal{S}}))^{*}\) coincides with \(M_{a}({\mathcal{S}})\) for a class of locally compact semigroups \({\mathcal{S}}\): this gives a partial solution to a conjecture raised by the authors. 相似文献
158.
The purpose of this paper is to visit a class of nonlinear reactive transport model in the case including advective and diffusive transport with the Michaelis-Menten reaction term. We apply the method so-called predictor homotopy analysis method (PHAM) which has been recently proposed to predict multiplicity of solutions of nonlinear BVPs. Consequently two consequential matters are indicated which confirms the authority of PHAM to identify multiple solutions: (i) The Talylor series solutions are improved by the so-called convergence-controller parameter (ii) The possibility of existence of multiple solutions is discovered in some cases for the model. 相似文献
159.
Arsham Borumand Saeid Akbar Rezaei Rajab Ali Borzooei 《Mathematics in Computer Science》2013,7(3):341-352
In this paper, we introduce some types of filters in BE-algebras and state some theorems which determine the relationship between these filters and other filters of a BE-algebra and by some examples we show that these notions are different. 相似文献
160.
In this note we first define the notions of (weak, strong) implicative hyper K-algebras. Then we show by examples that these notions are different. After that we state and prove some theorems which determine the relationship between these notions and (weak) hyper K-ideals. Also we obtain some relations between these notions and (weak) implicative hyper K-ideals. Finally, we study the implicative hyper K-algebras of order 3, in particular we obtain a relationship between the positive implicative hyper K-algebras and (weak, strong) implicative hyper K-algebras under a simple condition. 相似文献