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131.
Umar Hayat Philip N. Bartlett George H. Dodd John Barker 《Journal of Electroanalytical Chemistry》1987,220(2)
The electrochemical oxidation of diphenylamine in acetonitrile produces an adherent conducting polymer film at the electrode. Conductivity measurements on pressed pellets of this polymer give a room temperature conductivity of 10 S cm−1. The polymer can be cycled between 25 and 200°C without deterioration in the conductivity. Preliminary SEM/EDS studies suggest that there is one BF−4 counter ion for every four monomer units in the oxidised polymer film. 相似文献
132.
Khizar Hayat Mahmood Hassan Akhtar Awais Siddique Saleemi Hafiz Badaruddin Ahmad Naeem Akhtar 《Electroanalysis》2020,32(8):1664-1670
Herein, we report the development of a robust, sensitive, and selective non‐enzymatic electrochemical sensor for the detection of hydrogen peroxide (H2O2). The novel BA modified CN‐dot wrapped Cu2O‐nano‐frogspawn (FS@CN‐dot) sensor probe demonstrated a catalytic property towards H2O2 that allowed the highly sensitive electrochemical detection at a low reduction potential. The as prepared CN‐dot wrapped Cu2O hetero‐structured nanocomposite was analyzed using surface analysis methods to confirm the morphology, crystallinity, and oxidation states of various constituents and dopant elements. Further, the morphological analysis of the Cu2O nanoparticles revealed that the Cu2O retains frogspawns‐liked structure. Under the optimized experimental conditions, the sensor showed a wide dynamic range of H2O2 from 0.5 μM to 9 mM with a detection limit (LD) of 1.2±0.1 nM. The designed sensing probe showed good stability, high sensitivity, and selectivity even in the presence of potential interfering molecules. To check the reliability of the fabricated sensor in biomedical applications, the proposed sensing probe was successfully applied to monitor H2O2 in saliva of a gum‐diseased patient. To the best of our knowledge, this report is the first of its kind not only because of its novel construction style in terms of CN source, but also in terms of real sample applicability as well. 相似文献
133.
T. Hayat H. Mambili-Mamboundou F.M. Mahomed 《Nonlinear Analysis: Real World Applications》2009,10(1):368-374
This paper investigates the time independent unidirectional flow of a fourth grade fluid filling the porous half space. Flow modelling is based upon a modified Darcy’s law. Travelling wave and conditional symmetry solutions are developed. The graphs are plotted and discussed for the sundry parameters. 相似文献
134.
The exact analytic solutions of two problems of a second order fluid in presence of a uniform transverse magnetic field are investigated. The governing equation is of fourth order ordinary differential equation and is solved using perturbation method. In the first problem we discuss the flow of a second order fluid due to non-coaxial rotations of a porous disk and a fluid at infinity. In second problem the flow of a second order conducting fluid between two infinite plates rotating about the same axis is investigated, with suction or blowing along the axial direction. For second order conducting fluid it is observed that asymptotic solution exists for the velocity both in the case of suction and blowing. 相似文献
135.
136.
The Stokes and Rayleigh Stokes problems for a flat plate in a viscoelastic fluid has recently been generalized to an edge
and an exact analytical solution is obtained. In this paper, the edge problem has further been extended to the case of a rectangular
pipe and exact solutions are obtained for Maxwell and second grade fluids. Also, the flow due to an oscillating edge problem
is extended to generalized Maxwell fluid. 相似文献
137.
This paper looks at the unsteady three‐dimensional MHD flow of an elastico‐viscous fluid over a stretching surface. The analysis of mass transfer is also analyzed. The governing boundary layer equations are reduced into partial differential equations with three dependent variables through similarity transformations. The transformed system of equations is solved analytically by employing homotopy analysis method (HAM). Plots for various interesting parameters are presented and discussed. Numerical data for surface shear stresses and surface mass transfer in steady case are also tabulated. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
138.
This paper examines the magnetohydrodynamic boundary layer flow of Jeffrey fluid due to a rotating disk. The governing partial differential equations are first transformed into the coupled system of ordinary differential equations and then solved by using the homotopy analysis method. The influence of various involved physical parameters on the dimensionless radial and azimuthal velocities is sketched and analyzed. The variation of skin friction coefficients in radial and azimuthal directions is studied for various values of pertinent parameters. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
139.
This paper examines the unsteady two‐dimensional flow of a second‐grade fluid between parallel disks in the presence of an applied magnetic field. The continuity and momentum equations governing the unsteady two‐dimensional flow of a second‐grade fluid are reduced to a single differential equation through similarity transformations. The resulting differential system is computed by a homotopy analysis method. Graphical results are discussed for both suction and blowing cases. In addition, the derived results are compared with the homotopy perturbation solution in a viscous fluid (Math. Probl. Eng., DOI: 10.1155/2009/603916 ). Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
140.
In this paper, we study the dynamics of a stochastic Susceptible-Infective-Removed-Infective (SIRI) epidemic model with relapse. By constructing a suitable stochastic Lyapunov function, we establish sufficient conditions for the existence of an ergodic stationary distribution to the model. Moreover, sufficient conditions for extinction of the disease are also obtained. 相似文献