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131.
Journal of Statistical Physics - We consider a spin system containing pure two spin Sherrington–Kirkpatrick Hamiltonian with Curie–Weiss interaction. The model where the spins are... 相似文献
132.
Superperiodicity, chaos and coexisting orbits of ion-acoustic waves (IAWs) are studied in a multi-component plasma consisting of fluid ions, q -nonextensive cold and hot electrons and Maxwellian hot positrons. The significant impacts of the system parameters on superperiodic and nonlinear periodic IAWs are presented. Considering an external periodic perturbation various types of quasiperiodic and chaotic features for IAWs are studied in different parametric ranges through time series’ plots, phase spaces and Lyapunov exponents. It has been observed that there exist some coexisting orbits for IAWs. Coexisting orbits for IAWs in a classical electron–positron–ion plasma system are reported. 相似文献
133.
U. Pandey A. Mukherjee G. Samuel S. Banerjee H. D. Sarma M. Venkatesh 《Journal of Radioanalytical and Nuclear Chemistry》2008,275(2):243-246
Lanreotide, a somatostatin analogue, was radioiodinated with 125I to explore the possibility of using 123I labeled lanreotide as a diagnostic radiopharmaceutical for tumors overexpressing somatostatin (SST) receptors. Radioiodination
was carried out with 125I using chloramine T as the oxidant. The labeling yield was >90%. Characterization of 125I-Lanreotide was carried out by paper electrophoresis as well as HPLC. 125I-Lanreotide was purified by chromatography using a C18 Sep-Pak column. Radiochemical purity of the purified 125I-Lanreotide thus obtained was >99%. Significant tumor uptake of 125I-Lanreotide was observed in C57BL/6 mice bearing melanoma. 相似文献
134.
Nonlinear Dynamics - Control of spatially extended systems is an important and challenging topic of research. Previous control techniques rely on local or global feedback control. In this paper,... 相似文献
135.
The vortex dynamics at microwave frequencies in YBa2Cu3O7-δ (YBCO) films have been studied. We observe a peak in the microwave (4.88 and 9.55 GHz) surface resistance in some films in
magnetic fields up to 0.8 T. This is associated with the ‘peak-effect’ phenomenon and reflects the order-disorder transformation
of the flux line lattice near the transition temperature. Introduction of artificial pinning centers like columnar defects
created as a result of irradiation with 200 MeV Ag ion (at a fluence of 4×1010 ions/cm2) leads to the suppression of the peak in films previously exhibiting ‘peak effect’. 相似文献
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Tanmoy Banerjee 《Nonlinear dynamics》2012,68(4):565-573
The present paper reports an inductor-free realization of Chua??s circuit, which is designed by suitably cascading a single amplifier biquad based active band pass filter with a Chua??s diode. The system has been mathematically modeled with three-coupled first-order autonomous nonlinear differential equations. It has been shown through numerical simulations of the mathematical model and hardware experiments that the circuit emulates the behaviors of a classical Chua??s circuit, e.g., fixed point behavior, limit cycle oscillation, period doubling cascade, chaotic spiral attractors, chaotic double scrolls and boundary crisis. The occurrence of chaotic oscillation has been established through experimental power spectrum, and quantified with the dynamical measure like Lyapunov exponents. 相似文献