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91.
This paper contains the plasma maser interaction between high frequency nonresonant whistler R-mode and low frequency resonant ion acoustic mode in a relativistic plasma. It shows that the whistler R-mode grows through the plasma maser interaction between the relativistic electrons and the ion acoustic fluctuation.   相似文献   
92.
We give elementary proofs of seven Schläfli-type “mixed” modular equations recorded by Ramanujan on p. 86 of his first notebook. Previously, these equations were proved by Berndt by using the theory of modular forms. In the process, we also found three new Schläfli-type mixed modular equations of the same nature.  相似文献   
93.
M. Deka  A. Kumar  P. Chutia 《Ionics》2013,19(10):1367-1374
In this work, we have investigated the effect of dedoped (insulating) polyaniline (PAni) nanofibers on the electrical and electrochemical properties of poly(methyl methacrylate) (PMMA)-based gel electrolytes. PAni nanofibers have been synthesized using interfacial polymerization technique. By analysis of X-ray diffraction (XRD) and impedance spectroscopy results, it has been demonstrated that the incorporation of dedoped PAni nanofibers up to a moderate concentration (4 wt%) to PMMA–(PC?+?DEC)–LiClO4 gel polymer electrolyte system significantly enhances the ionic conductivity of the electrolyte system, which can be attributed to the inhibition of polymer chain reorganization upon dispersion of high aspect ratio nanofibers in PMMA matrix resulting in reduction in polymer crystallinity, which gives rise to an increase in ionic conductivity. At higher concentration, dedoped nanofibers appear to get phase separated and form insulating clusters, which impede ionic transport. The phase separation phenomena at higher fraction of nanofibers are confirmed by XRD. Studies on electrochemical behavior reveal that electrochemical potential window increases with the increase of nanofibers loading.  相似文献   
94.
95.
The Ramanujan Journal - Recently, Lin introduced two new partition functions $$\hbox {PD}_{\mathrm{t}}(n)$$ and $$\hbox {PDO}_{\mathrm{t}}(n)$$, which count the total number of tagged parts over...  相似文献   
96.
A series of 4-hydroxy-6-methoxyaurones and 4,6-dimethoxyaurones has been synthesised and tested for their binding affinity toward the nucleotide-binding domain of P-glycoprotein, an ABC (ATP-Binding Cassette) transporter which mediates the resistance of cancer cells to chemotherapy. These compounds differ from each other by the nature of the substituent on the aurone B-ring. The binding affinity seems to be linked to the nature of the substituent, as well as to the presence or the absence of a hydroxy group at position 4. The most active compounds were 4'-bromo-4-hydroxy-6-methoxyaurone and 4-hydroxy-4'-iodo-6-methoxyaurone.  相似文献   
97.
Weak Galerkin finite element method is introduced for solving wave equation with interface on weak Galerkin finite element space $(\mathcal{P}_k(K), \mathcal{P}_{k−1}(∂K), [\mathcal{P}_{k−1}(K)]^2).$ Optimal order a priori error estimates for both space-discrete scheme and implicit fully discrete scheme are derived in $L^∞(L^2)$ norm. This method uses totally discontinuous functions in approximation space and allows the usage of finite element partitions consisting of general polygonal meshes. Finite element algorithm presented here can contribute to a variety of hyperbolic problems where physical domain consists of heterogeneous media.  相似文献   
98.
Journal of Fluorescence - Mercury (Hg) causes serious health issues in its all forms. Deficiency as well as excess of copper ion (Cu2+) in human body is hazardous. A series of four compounds have...  相似文献   
99.
100.
The purpose of this paper is to study the finite element method for second order semilinear elliptic interface problems in two dimensional convex polygonal domains. Due to low global regularity of the solution, it seems difficult to achieve optimal order of convergence with straight interface triangles [Numer. Math., 79 (1998), pp. 175–202]. For a finite element discretization based on a mesh which involve the approximation of the interface, optimal order error estimates in L 2 and H 1-norms are proved for linear elliptic interface problem under practical regularity assumptions of the true solution. Then an extension to the semilinear problem is also considered and optimal error estimate in H 1 norm is achieved.  相似文献   
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