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161.
162.
We propose an approach to solve a nonlinear multi-objective problem subject to fuzzy relation inequalities with max-Archimedean-t-norm composition by a genetic algorithm. The additive generator of Archimedean t-norms is utilized to reform the existent genetic algorithm to solve the constrained nonlinear multi-objective optimization problems. We consider thoroughly the feasible set of the fuzzy relation inequality systems in three possible cases, namely “≤”, “≥” and the combination of them. In general, their feasible sets are nonconvex which are completely determined by one vector as their maximum solution and a finite number of minimal solutions. The maximum and minimal solutions are formulated by using the additive generator. Additionally, we present some conditions for each case under which the problem can be reduced. Finally, each reduced problem is solved by the genetic algorithm and the efficiency of the proposed method is shown by some numerical examples. 相似文献
163.
The nonlinear aspects of nonplanar dust acoustic (DA) solitary waves are investigated in an unmagnetized complex plasma comprising of cold dust grains,kappa-distributed ions as well as electrons.The nonplanar DA solitons are studied based on the reductive perturbation technique.It is shown that the evolution of DA solitons is governed by a spherical Kadomtsev-Petviashvili (sKP) equation and then the impact of suprathermality on the spatial structure as well as the nature of DA soliton is studied.It seems that the properties of DA solitons in nonplanar geometry are quite different from that of the planar solitons. 相似文献
164.
S. Jafar Hoseini Mehrangiz Bahrami Mahnaz Maddahfar Roghayeh Hashemi Fath Mahmoud Roushani 《应用有机金属化学》2018,32(1)
This study describes the polymerization of graphene oxide (GO) nanosheet to reduced‐GO‐aminoclay (RGC) by covalent functionalization of chemically reactive epoxy groups on the basal planes of GO with amine groups of magnesium phyllosilicate clay (known as aminoclay). The resulting RGC sheets were characterized and applied to support platinum nanostructures at toluene/water interface. Pt nanoparticles (NPs) with diameters about several nanometers were adhered to RGC sheets by chemical reduction of [PtCl2(cod)] (cod = cis,cis‐1,5‐cyclooctadiene) complex. Catalytic activity of Pt NPs thin films were investigated in the methanol oxidation reaction. Cyclic voltammetry results exhibit that the Pt/reduced‐GO (RGO) and Pt/RGC thin films showed improved catalytic activity in methanol oxidation reaction in comparison to other Pt NPs thin films, demonstrating that the prepared Pt/RGO and Pt/RGC thin films are promising catalysts for direct methanol fuel cell. 相似文献
165.
Ramin Ghorbani-Vaghei Yaser Maghbooli Azadeh Shahriari Jafar Mahmoodi 《Molecular diversity》2016,20(4):907-917
166.
Quantum dynamics of electron transfer (capture) phenomenon during the H–He2+ collision is investigated by solving two-dimensional time-dependent Schrödinger equation numerically using a third-order split operator technique. Results of this study, represented as the snapshots of the electron wavepacket time evolution, show significantly different dynamics for the electron of different initial orbitals (1s, 2s, 2p x and 2p y ) of the incoming hydrogen atom. This electron transfer dynamics is also detailed by calculating expansion coefficients of the projection of the evolving wavepacket onto the stationary eigenfunctions of the H and He+ species to investigate evolution of the electron density around each nucleus during the collision. The instantaneous and overall electron densities captured by the He2+ nucleus from the H atom are calculated and analyzed. It is also shown evidently and concluded that due to its quantum nature, electron crawls from one nucleus to the other in an electron transfer process during an atom–ion collision. 相似文献
167.
168.
S. Jafar Hoseini Hasan Nasrabadi Mahboobeh Azizi Alireza Salimi Beni Reza Khalifeh 《合成通讯》2013,43(12):1683-1691
Application of Fe3O4 nanoparticles (NPs) as a robust, very efficient, and magnetically recoverable catalyst was investigated in Friedel–Crafts acylation (FCA) of ferrocene and aromatic compounds. This reaction was performed with acid chlorides in solvent-free conditions at room temperature. The catalyst was easily separated by an external magnetic field from the reaction mixture. The separated catalyst was recycled for several consecutive runs without appreciable loss of its catalytic activity. Supplemental materials are available for this article. Go to the publisher's online edition of Synthetic Communications® to view the free supplemental file. 相似文献
169.
Jaber Jahanbin Sardroodi Jafar Azamat Maryam Atabay 《The Journal of chemical thermodynamics》2011,43(12):1886-1892
Osmotic coefficients of the binary solutions of two room-temperature ionic liquids (1-butyl-3-methylimidazolium chloride and bromide) in methanol and ethanol have been measured at T = 298.15 K by the isopiestic method. The experimental osmotic coefficient data have been correlated using a forth-order polynomial in terms of (molality)0.5, with both, ion interaction model of Pitzer and electrolyte non-random two liquid (e-NRTL) model of Chen. The values of vapor pressures of above-mentioned solutions have been calculated from the osmotic coefficients. The model parameters fitted to the experimental osmotic coefficients have been used for prediction of the mean ionic activity coefficients of those ionic liquids in methanol and ethanol. 相似文献
170.
The aim of this paper is to present an efficient numerical procedure for solving the two-dimensional nonlinear Volterra integro-differential
equations (2-DNVIDE) by two-dimensional differential transform method (2-DDTM). The technique that we used is the differential
transform method, which is based on Taylor series expansion. Using the differential transform, 2-DNVIDE can be transformed
to algebraic equations, and the resulting algebraic equations are called iterative equations. New theorems for the transformation
of integrals and partial differential equations are introduced and proved. The reliability and efficiency of the proposed
scheme are demonstrated by some numerical experiments. 相似文献