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31.
Afzal Qamar Akram Safia Ellahi R. Sait Sadiq M. Chaudhry Faryal 《Journal of Thermal Analysis and Calorimetry》2021,144(6):2203-2218
Journal of Thermal Analysis and Calorimetry - This article addresses the influence of double-diffusivity convection in nanofluids in relation to peristaltic flow of magneto couple stress fluid in a... 相似文献
32.
We have considered the generalized version of chiral schwinger model with the Lorentz covariant masslike term for gauge field with the choice a ? r2 =?0. We carry out the quantization by the canonical Dirac method of both the gauge-invariant and non-invariant version of this model to determine the phase space structure. Therefore we have shown that the gauge invariant theory has the same physical spectrum as that of the original gauge noninvariant formulation.
相似文献33.
Fazia Derridj Karima Si Larbi Julien Roger Safia Djebbar Henri Doucet 《Tetrahedron》2012,68(36):7463-7471
The palladium-catalyzed direct arylation at C2 or C5 of free NH2 substituted thiophene derivatives was found to proceed in moderate to high yields using a variety of aryl halides. The choice of potassium acetate as the base was found to be crucial to inhibit the amination reaction and to promote the direct arylation. 相似文献
34.
In the present paper we discuss the magnetohydrodynamic (MHD) peristaltic flow of a hyperbolic tangent fluid model in a vertical asymmetric channel under a zero Reynolds number and long wavelength approximation. Exact solution of the temperature equation in the absence of dissipation term has been computed and the analytical ex- pression for stream function and axial pressure gradient are established. The flow is analyzed in a wave frame of reference moving with the velocity of wave. The expression for pressure rise has been computed numerically. The physical features of pertinent parameters are analyzed by plotting graphs and discussed in detail. 相似文献
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The present paper investigates the peristaltic transport of a couple stress fluid in an asymmetric channel with the effect
of the induced magnetic field. The exact solutions of momentum and the magnetic field equations have been calculated under
the assumptions of long wave length and low but finite Reynolds number. The expression for pressure rise has been computed
numerically using mathematics software Mathematica. The graphical results have been presented to discuss the physical behavior
of various physical parameters of interest. Finally, the trapping phenomena have been discussed for various physical parameters. 相似文献
36.
Muhammad Asim Akbar Hussain Safia Khan Javeria Arshad Tehmeena Maryum Butt Amina Hana Mehwish Munawar Farhat Saira Malika Rani Arshad Mahmood Naveed Kausar Janjua 《Molecules (Basel, Switzerland)》2022,27(18)
Hexanary high-entropy oxides (HEOs) were synthesized through the mechanochemical sol-gel method for electrocatalytic water oxidation reaction (WOR). As-synthesized catalysts were subjected to characterization, including X-ray diffraction (XRD), Fourier transforms infrared (FTIR) analysis, and scanning electron microscopy (SEM). All the oxide systems exhibited sharp diffraction peaks in XRD patterns indicating the defined crystal structure. Strong absorption between 400–700 cm−1 in FTIR indicated the formation of metal-oxide bonds in all HEO systems. WOR was investigated via cyclic voltammetry using HEOs as electrode platforms, 1M KOH as the basic medium, and 1M methanol (CH3OH) as the facilitator. Voltammetric profiles for both equiatomic (EHEOs) and non-equiatomic (NEHEOs) were investigated, and NEHEOs exhibited the maximum current output for WOR. Moreover, methanol addition improved the current profiles, thus leading to the electrode utility in direct methanol fuel cells as a sequential increase in methanol concentration from 1M to 2M enhanced the OER current density from 61.4 to 94.3 mA cm−2 using NEHEO. The NEHEOs comprising a greater percentage of Al, ([Al0.35(Mg, Fe, Cu, Ni, Co)0.65]3O4) displayed high WOR catalytic performance with the maximum diffusion coefficient, D° (10.90 cm2 s−1) and heterogeneous rate constant, k° (7.98 cm s−1) values. These primary findings from the EC processes for WOR provide the foundation for their applications in high-energy devices. Conclusively, HEOs are proven as novel and efficient catalytic platforms for electrochemical water oxidation. 相似文献
37.
M. M. Taqui Khan Badar Taqui Khan Safia Begum 《Reaction Kinetics and Catalysis Letters》1987,34(1):105-111
Catalytic homogeneous hydrogenation of 1-pentene catalyzed by bis(diphenylphosphinoethylamine) chlororhodium(I) [RhClHN(CH2CH2PPh2)2](1) was investigated over the temperature range 10–20°C under 1 atm of hydrogen pressure. The dependence of the rate of hydrogenation on temperature, catalyst and substrate concentration in solution is reported. The thermodynamic and activation parameters for the hydrogenation of 1-pentene catalyzed by1 were computed and compared with those of cyclohexene and 1-heptene.
1-, () (I), [RhClHN(CH2CH2PPh2)2] (1), 10–20°C 1 . , . 1- 1 1-.相似文献
38.
In the present study, we investigated the effects of slip and induced magnetic field on the peristaltic flow of a Jeffrey fluid in an asymmetric channel. The governing two‐dimensional equations for momentum, magnetic force function and energy are simplified by using the assumptions of long wavelength and low but finite Reynolds number. The reduced problem has been solved by Adomian decomposition method (ADM) and closed form solutions have been presented. Further, the exact solution of the proposed problem has also been computed and the mathematical comparison shows that both solutions are almost similar. The effects of pertinent parameters on the pressure rise per wavelength are investigated using numerical integration. The expressions for pressure rise, friction force, velocity, temperature, magnetic force function and the stream lines against various physical parameters of interest are shown graphically. Moreover, the behavior of different kinds of wave shape are also discussed. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
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Periodic mesoporous organosilica (PMO) with two-dimensional hexagonal symmetry was synthesised using a bridged silsesquioxane (CH3O)3Si-CH2-CH2-Si(CH3O)3 as precursor and polyoxyethylene non-ionic surfactant (Brij-56) as template. The hybrid material was characterised by X-ray diffraction, N2 adsorption, TEM, and solid-state 29Si MAS NMR spectroscopy. 相似文献