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11.
In this paper monotone methods have been developed for equations arising in transport processes in a Banach space. This method proves the existence of extremal solutions for such equations. The advantage of the method for such type of equations is that the successive iterates are solutions of the corresponding initial value problems.  相似文献   
12.
In this paper we obtain sufficient conditions for strict stability to hold for dynamic systems on time scales.  相似文献   
13.

The notion of fuzzy difference equation is introduced. Using Lyapunov type of function a comparison theorem for the fuzzy difference equation is obtained in terms of ordinary difference equations, which is used as a tool to study the stability results of the fuzzy difference equations.  相似文献   
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The extended quasilinearization method of Lakshmikantham et al. (J. Optim. Theory Appl. 87 (1995), 379-401) for the first order initial value problems is applied to the nonlinear systems. It is shown that there exist monotone sequences which converge uniformly to the unique solution of the system and the convergence is quadratic. Futhermore, a variety of results are obtained by splitting the functions involved into the difference of two convex or two concave functions, each of which is interesting by itself, with the same conclusion. Moreover, new results are extracted, as a byproduct, from the present results which offer simultaneous bounds for the cases where there is no splitting involved  相似文献   
16.
The existence of coupled maximal and minimal quasi solutions of a system of second order periodic boundary value problems is discussed when the right hand side possesses a mixed monotone property.  相似文献   
17.
GC/FID has been used for the determination of a fatty acid based lubricity improver in diesel fuel. The method makes use of phase transfer catalysis for the enrichment of the lubricity improver from the diesel matrix. The use of phase transfer catalysis for the simultaneous extraction, preconcentration and derivatisation of the fatty acids enables determination of concentrations of 20 mg L?1. The method has been successfully applied to the analysis of diesel streams from various sources. The effect of the diesel matrix has also been investigated and it does not affect the recovery of the additive.  相似文献   
18.
Various types of comparison results for first and second order periodic boundary value problems are developed. It is hoped that these comparison results play an important role in the existence theory of boundary value problems at resonance.  相似文献   
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BaTiO3 nanoparticles prepared by wet chemical method were thermally grown onto well cleaned glass substrates under the vacuum of 2 × 10−5 Torr, using 12A4 Hind Hivac coating unit. An Al–BaTiO3–Al sandwich structure has been used for electrical conduction properties in the temperature range 303–423 K. The composition of nanoparticles and thin films were identified by EDS spectrum. The structural studies have been performed by the X-ray diffraction (XRD) technique. The X-ray analysis showed that the nano particle has a tetragonal structure and deposited films at a lower thickness amorphous in nature, whereas the crystallinity increases with increase of thickness. In the DC conduction studies, the current–voltage characteristics of the films showed ohmic conduction in the low voltage region. In the higher voltage region, a space charge limited conduction (SCLC) takes place due to the presence of the trapping level. The activation energy was estimated and the values found to decrease with increasing applied voltage. The zero field value of the activation energy is found to be 0.31 eV. The free carrier mobility, carrier density and trap density values were calculated and reported in this paper.  相似文献   
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