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211.
Parisa Bakhtiari Alicia Cordero Taher Lotfi Kathayoun Mahdiani Juan R. Torregrosa 《Nonlinear dynamics》2017,87(2):913-938
In this work, we analyze the dynamical behavior on quadratic polynomials of a class of derivative-free optimal parametric iterative methods, designed by Khattri and Steihaug. By using their parameter as an accelerator, we develop different methods with memory of orders three, six and twelve, without adding new functional evaluations. Then a dynamical approach is made, comparing each of the proposed methods with the original ones without memory, with the following empiric conclusion: Basins of attraction of iterative schemes with memory are wider and the behavior is more stable. This has been numerically checked by estimating the solution of a practical problem, as the friction factor of a pipe and also of other nonlinear academic problems. 相似文献
212.
Due to increasing demands for ecofriendly processes within the framework of green chemistry, and having shown substantial properties, especially in terms of toxicity, biodegradability, cost, and ease of preparation under ambient conditions, deep eutectic solvents (DESs) have become a suitable candidate as green solvents for reaction media in the past decade. In this work, condensation reaction of some para- and meta-substituted benzaldehydes and Malononitrile was kinetically investigated in ethylene glycol-choline chloride (ethaline) as a DES mixed with water, in the whole range of mole fractions, at room temperature. The correlation of second-order rate coefficients based on Hammett's substituent constants yield a linear straight line with positive slope in different mole fractions of ethaline–water mixtures. The measured second-order rate coefficients of the reaction showed a dramatic variation in ethaline–water mixtures with the increasing mole fraction of water. 相似文献
213.
Studying earthquakes and the associated geodynamic processes based on the complex network theory enables us to learn about the universal features of the earthquake phenomenon. In addition, we can determine new indices for identification of regions geophysically. It was found that earthquake networks are scale free and its degree distribution obeys the power law. Here we claim that the q-exponential function is better than power law model for fitting the degree distribution. We also study the behavior of q parameter (nonextensivity measure) with respect to resolution. It was previously asserted in Eur. Phys. J. B (2012) 85: 23; that the topological characteristics of earthquake networks are dependent on each other for large values of the resolution. A peak in the plot of q against resolution determines the beginning of the assertion range. 相似文献
214.
Tin oxide films have been prepared by oxidation of Sn thin films deposited by thermal evaporation method onto glass substrates. The oxidation of films was done, in air at a temperature of 500 °C, from 20 to 120 min. The oxidized films were characterized by X-ray diffraction (XRD), Rutherford backscattering spectroscopy (RBS), photoluminescence spectroscopy (PL) and surface profilometer. The XRD patterns show that the crystalline structure of the oxidized Sn films improves with the annealing time. The tetragonal SnO2 phase (cassiterite) was obtained after 120 min of annealing with grains sizes between 15 and 20 nm. The thickness of oxide films, as function of the annealing time, follows a parabolic law. The O/Sn atomic ratio increases with the annealing time indicating an improvement of the films quality. Tin interstitials defects density, calculated from PL spectra using Smakula's formula, was found to decrease with the increasing annealing time. Tin interstitials defects density was found proportional to the increasing oxygen density (deduced from RBS). A fit of this proportionality allowed us to quantify the tin cations and oxygen anions diffused through the oxide films. 相似文献
215.
F. Boudjema A. Djouadi J. L. Kneur 《Zeitschrift fur Physik C Particles and Fields》1993,57(3):425-449
We analyse the discovery potentials of future colliders with respect to excited fermions which are expected in models of fermionic substructure. After discussing the possibilities offered by LEP, we will consider in detail the Next Linear Collider in itse + e ?,eγ and γγ modes [where the high-energy photon beams are obtained through back-scattering of laser light]. In addition, sinceeP colliders are well adapted to the search of the first generation of excited leptons, we include a study of their possible manifestation at HERA and LEP/LHC. We give complete and compact formulae for decay widths, production cross sections and angular distributions. Furthermore, we analyse in some detail the polarisation of the produced excited fermions which allows for an easy reconstruction of the correlations between the initial state and the decay products of the heavy fermions. 相似文献
216.
G. R. Jahanshahloo F. Hosseinzadeh Lotfi M. Moradi 《Applied mathematics and computation》2005,160(3):6349
An issue of considerable importance, how to allocate a common revenue in an equitable manner across a set of competing entities. This paper introduces a new approach to obtaining allocation common revenue on all decision making units (DMUs) in such a way that the relative efficiency is not changed. In this method for determining allocation common revenue dose not need to solving any linear programming. A numerical example is provided to illustrate the results of the analysis. 相似文献
217.
Saied Saeed Hosseiny Davarani Leila Masoomi Mohammad Hossein Banitaba Hamid Reza Lotfi Zadeh Zhad Omid Sadeghi Azam Samiei 《Chromatographia》2012,75(7-8):371-377
This paper presents a simple and convenient analytical method for determination of 1,4-dioxane in surfactants and detergents by using a novel SPME fiber. For the preparation of the fiber, the surface of a fused silica capillary tubing was modified by means of aluminium tri-tert-butoxide in a straightforward grafting process. The surface of our proposed fiber provides a Lewis acid–base interaction with analyte functional groups. The main factors affecting the extraction were optimized by using a central composite design method, which leads to the following optimum conditions: extraction temperature of 34?°C, extraction time of 4?min, equilibrium time of 13?min, and salt content of 25% (w/v). The optimum conditions showed a linear range from 0.005 to 60?μg?g?1. LOD and LOQ of the proposed method were estimated to be 0.0015 and 0.005?μg?g?1, respectively. This method was also applied for the analysis of some real samples including ethoxylated fatty alcohol, sodium lauryl ether sulfate, dish-washing agents, and shampoos by using the standard addition method. 相似文献
218.
Jaymand Mehdi Lotfi Mehrdad Barar Jaleh Kimyai Soodabeh 《Research on Chemical Intermediates》2017,43(10):5707-5722
Research on Chemical Intermediates - We describe synthesis and characterization of a series of novel multifunctional methacrylate-based dental monomers. Triethanolamine was reacted with glycidyl... 相似文献
219.
Monaem Balti Bernadette Norberg Mohamed Lotfi Efrit Steve Lanners Johan Wouters 《Acta Crystallographica. Section C, Structural Chemistry》2016,72(5):421-425
4‐Phenyl‐4‐thiazoline‐2‐thiol is an active pharmaceutical compound, one of whose activities is as a human indolenamine dioxygenase inhibitor. It has been shown recently that in both the solid state and the gas phase, the thiazolinethione tautomer should be preferred. As part of both research on this lead compound and a medicinal chemistry program, a series of substituted arylthiazolinethiones have been synthesized. The molecular conformations and tautomerism of 4‐(2‐methoxyphenyl)‐4‐thiazoline‐2‐thione and 4‐(4‐methoxyphenyl)‐4‐thiazoline‐2‐thione, both C10H9NOS2, are reported and compared with the geometry deduced from ab initio calculations [PBE/6‐311G(d,p)]. Both the crystal structure analyses and the calculations establish the thione tautomer for the two substituted arylthiazolinethiones. In the crystal structure of the 2‐methoxyphenyl regioisomer, the thiazolinethione unit was disordered over two conformations. Both isomers exhibit similar hydrogen‐bond patterns [R22(8) motif] and form dimers. The crystal packing is further reinforced by short S…S interactions in the 2‐methoxyphenyl isomer. The conformations of the two regioisomers correspond to stable geometries calculated from an ab initio energy‐relaxed scan. 相似文献
220.
Lotfi Jlali 《Mathematical Methods in the Applied Sciences》2017,40(7):2713-2736
In this paper, we prove a global well posedness of the three‐dimensional incompressible Navier–Stokes equation under an initial data, which belong to the non‐homogeneous Fourier–Lei–Lin space for σ ? ? 1 and if the norm of the initial data in the Lei–Lin space is controlled by the viscosity. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献