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31.
A mathematical model of mediated bioelectrocatalysis is restudied in this paper. Here He’s Homotopy perturbation method is implemented to give approximate and analytical solutions of steady-state non-linear reaction diffusion equation containing a non-linear term related to Michaelis–Menten kinetics of the enzymatic reaction. Approximate analytical expressions for mediator concentration and current have been derived for all values of saturation parameter α and reaction diffusion parameter k for the various types of boundary conditions. The Homotopy perturbation method which produces the solutions in terms of convergent series, requiring no linearization or small perturbation. These analytical results are compared with numerical results (Matlab program) and are found to be in good agreement.  相似文献   
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Cryoinfarction in rats was carried out by placing the cooled probe directly on the midway of left anterior descending coronary artery. This caused damage to the blood vessel, hindering blood flow to the distal part of the left ventricle. Gross pathology showed around 26% infarction at 24 h. Histopathology revealed death of cardiomyocytes with blood vessel congestion at the end of 24 h, inflammatory infiltrate at 48 h, fibrotic scar by 96 h and collagen deposition by 192 h. Acute myocardial infarction biomarkers such as Cardiac Troponin T, Creatine Kinase MB and NT pro BNP were shown to be elevated by 4 h. ECG showed an ST segment elevation by 96 h. This cryoinfarction model was suitable to study changes taking place during acute myocardial infarction in humans.  相似文献   
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Polymerization of methyl methacrylate in the presence of a mixed ligand complex, [N,N′-ethylenebis(salicylideneiminato)](acetylacetonato)cobalt(III) in benzene was studied. The rate of polymerization was proportional to the square root of the concentration of the chelate and the monomer exponent was 1.67 and 1.69 at 60 and 70°C, respectively. The activation energy and the kinetic and transfer constants were evaluated. A free-radical mechanism has been proposed.  相似文献   
35.
The mixed gas (Ar + N2) plasma has been generated by a 6 KW, 10.3 MHz radio frequency oscillator. The flame got extinguished if N2 exceeded more than 20% of Ar. The Boltzmann plot using spectral intensities of Ar I and NI lines in the wavelength range 4000–4510 Å have been used to determine the excitation temperature. The results show that excitation equilibrium between two species exist since the temperatures are found to be nearly same for both species.  相似文献   
36.
Spacing effects on hydrodynamics of heave plates on offshore structures   总被引:1,自引:0,他引:1  
The nonlinear viscous flow problem associated with a heaving vertical cylinder with two heave plates in the form of two circular disks attached is solved using a finite difference method. Numerical experiments are carried out to investigate the spanwise length effects on the hydrodynamic properties, such as added mass and damping coefficients. Over a Keulegan–Carpenter (KC) number range from 0.1 to 0.6 at frequency parameter (β=7.869×107), calculations indicate that a KC-dependent critical value of spanwise length L/Dd (L—the distance between the disks, and Dd—the diameter of the disks) exists. A significant influence of L/Dd on the vortex shedding patterns around the disks and the hydrodynamic coefficients is revealed when L/Dd is smaller than the critical value due to strong interaction between vortices of different disks. Beyond that limit, however, both added mass and damping coefficients are shown to be rather stable, indicating the independence of the vortex shedding processes of different disks.  相似文献   
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Journal of Solid State Electrochemistry - In the present investigation, we have synthesized Ni3V2O8@GO composite by co-precipitation method and designed as a new anode material for supercapacitor...  相似文献   
39.
Newly synthesised fluorescent chemosensor ADDTU contains the thiourea receptor connected to the acridinedione (ADD) fluorophore via a covalent bond, giving rise to a fluorophore-receptor motif. In this fluorescent chemosensor, the anion recognition takes place at the receptor site which result in the concomitant changes in the photophysical properties of a ADD fluorophore by modulation of photoinduced electron transfer (PET) process. The binding ability of these sensor with the anions F(-), Cl(-), Br(-), I(-), HSO(4)(-), ClO(4)(-), AcO(-), H(2)PO(4)(-) and BF(4)(-) (as their tetrabutylammounium salts) in acetonitrile were investigated using UV-vis, steady state and time-resolved emission techniques. ADDTU system allows for the selective fluorescent sensing of AcO(-), H(2)PO(4)(-) and F(-) over other anions in acetonitrile.  相似文献   
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