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991.
Gianolio E Maciocco L Imperio D Giovenzana GB Simonelli F Abbas K Bisi G Aime S 《Chemical communications (Cambridge, England)》2011,47(5):1539-1541
A new dual MRI/SPECT pH-responsive agent where the SPECT active moiety acts as reporter of the concentration making it possible to exploit the responsiveness of the MRI probe. 相似文献
992.
Amgad Salama M. F. El-Amin Ibrahim Abbas Shuyu Sun 《Archive of Applied Mechanics (Ingenieur Archiv)》2011,81(12):1865-1876
The problem of viscous dissipation and thermal dispersion in saturated porous medium is numerically investigated for the case
of non-Darcy flow regime. The fluid is induced to flow upward by natural convection as a result of a semi-infinite vertical
wall that is immersed in the porous medium and is kept at constant higher temperature. The boundary layer approximations were
used to simplify the set of the governing, nonlinear partial differential equations, which were then non-dimensionalized and
solved using the finite elements method. The results for the details of the governing parameters are presented and investigated.
It is found that the irreversible process of transforming the kinetic energy of the moving fluid to heat energy via the viscosity
of the moving fluid (i.e., viscous dissipation) resulted in insignificant generation of heat for the range of parameters considered
in this study. On the other hand, thermal dispersion has shown to disperse heat energy normal to the wall more effectively
compared with the normal diffusion mechanism. 相似文献
993.
Abbas Moameni 《Journal of Functional Analysis》2011,260(9):2674-2715
We study the concept and the calculus of Non-convex self-dual (Nc-SD) Lagrangians and their derived vector fields which are associated to many partial differential equations and evolution systems. They indeed provide new representations and formulations for the superposition of convex functions and symmetric operators. They yield new variational resolutions for large class of Hamiltonian partial differential equations with variety of linear and nonlinear boundary conditions including many of the standard ones. This approach seems to offer several useful advantages: It associates to a boundary value problem several potential functions which can often be used with relative ease compared to other methods such as the use of Euler-Lagrange functions. These potential functions are quite flexible, and can be adapted to easily deal with both nonlinear and homogeneous boundary value problems. Additionally, in most cases the solutions generated using this new method have greater regularity than the solutions obtained using the standard Euler-Lagrange function. Perhaps most remarkable, however, are the permanence properties of Nc-SD Lagrangians; their calculus is relatively manageable, and their applications are quite broad. 相似文献
994.
Some common fixed point theorems due to Abbas and Khan [M. Abbas, A.R. Khan, Common fixed points of generalized contractive hybrid pairs in symmetric spaces, Fixed Point Theor. Appl. 2009 (2009) 11, Article ID 869407, doi:10.1155/2009/869407], and Abbas and Rhoades [M. Abbas, B.E. Rhoades, Common fixed point theorems for hybrid pairs of occasionally weakly compatible mappings defined on symmetric spaces, Pan. Amer. Math. J. 18 (1) (2008) 55-62] are proved for two new classes of hybrid pair of mappings which contain occasionally weakly compatible hybrid pairs as a proper subclass. Consequently, some results proved by Hussain et al. [N. Hussain, M.A. Khamsi, A. Latif, Common fixed points for JH-operators and occasionally weakly biased pairs under relaxed conditions, Nonlinear Anal. 74 (2011) 2133-2140], Bhatt et al. [A. Bhatt, et al., Common fixed point theorems for occasionally weakly compatible mappings under relaxed conditions, Nonlinear Anal. 73 (2010) 176-182] and many others are extended to hybrid pair of mappings. Examples are also presented to support the concepts defined in the paper. 相似文献
995.
996.
997.
Safeer Hussain Khan Y. J. Cho Mujahid Abbas 《Journal of Applied Mathematics and Computing》2011,35(1-2):607-616
We modify an iteration process of Agarwal et al. (J. Nonlinear Convex Anal. 8(1):61–79, 2007) to the case of two mappings and prove some weak and strong convergence theorems for two asymptotically nonexpansive mappings. We also point out that this process cannot be used for three mappings in its existing form even for nonexpansive mappings. We have to impose an extra condition to get convergence. We give an example to show that there do exist two nonexpansive mappings satisfying that condition. 相似文献
998.
999.
Abstract
The derivatization of a glassy carbon electrode surface was achieved with and without electrochemical reduction of various diazonium salts in acetonitrile solutions. The surfaces were characterized, before and after their attachment, by cyclic voltammetry and electrochemical impedance spectroscopy to evidence the formation of a coating on the carbon surface. The results were indicative of the presence of substituted phenyl groups on the investigated surface. Also, the effects of diazonium thin films at the surface of a glassy carbon electrode, modification time, and salt concentration on their electrochemical responses in the presence of the Fe(CN)63−/4− probe were investigated. Electrochemical impedance measurements indicated that the kinetics of electron transfer is slowed down when the time and the concentration used to modify the glassy carbon electrode are increased. We therefore modified a glassy carbon surface via its derivatization with and without electrochemical reduction of various diazonium salts in acetonitrile solution. 相似文献1000.
Abbas Rahmati 《Tetrahedron letters》2010,51(22):2967-2970
A one-pot, three-component condensation reaction of an aldehyde, 3-amino-5-methylpyrazole and ethyl cyanoacetate in ethanol to give 4-aryl-3-methyl-6-oxo-4,5,6,7-tetrahydro-2H-pyrazolo[3,4-b]pyridine-5-carbonitriles, in high yields, at reflux, using a catalytic amount of p-toluenesulfonic acid, is described. 相似文献