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121.
It is proposed to consider the scalings of anomalous transport (superdiffusion), determined experimentally in turbulent plasma of the Earth’s magnetosphere and laboratory plasma of thermonuclear facilities and processed using modern statistical cascade models of strong turbulence with intermittency, also within the approach of physical kinetics to the theory of plasma turbulence.  相似文献   
122.
The Cherenkov radiation of generalized Swihart waves is investigated in connection with the slow motion of an Abrikosov-Josephson vortex, which corresponds to a 2 π kink in the phase difference of Cooper pairs on opposite sides of a tunnel junction. The radiative friction force acting on such a vortex is determined. An evaluation is made of the steady-state vortex velocity when the accelerating influence of an electric current through the Josephson junction is compensated by radiative slowing of the vortex due to Cherenkov radiation from the Abrikosov-Josephson vortex. Fiz. Tverd. Tela (St. Petersburg) 39, 444–448 (March 1997)  相似文献   
123.
We have established the dependences of the maximum Weibel instability growth rate and the corresponding wavenumber on the degree of anisotropy in the photoelectron distribution formed through tunnel atomic ionization in the field of a circularly polarized short laser pulse. We show how the relaxation of the initial distribution of photoelectrons due to their collisions with ions affects the pattern of generation of a quasi-static magnetic field.  相似文献   
124.
A motion of slow and fast vortices in a waveguide-coupled Josephson junction induced by a transport current flowing through the entire structure is studied; the coupling is not assumed to be weak. For a fast vortex, conditions are established under which current oscillations due to energy dissipation via Cherenkov radiation of Swihart waves become comparable to the current compensating for ohmic losses in the Josephson junction, waveguide, and adjacent superconductors. For a slow vortex, it is proved that intermediate and strong couplings of the Josephson junction to the waveguide shift current oscillations to the velocity range below the Swihart velocity of the Josephson junction.  相似文献   
125.
In this paper we evaluate theoretically the modification of the distribution function of slow subthermal electrons heated by radiation in a completely ionized plasma. The new solution we have found to the kinetic equation under conditions typical of weak-collisional plasmas can be used to predict new nonlinear behavior arising from perturbations of the nonuniform electron density and the coefficient of nonlocal heat transfer that depend on the intensity of the radiation heating the plasma, which is absorbed via inverse bremsstrahlung. It is predicted that this new nonlinear behavior manifests itself at unexpectedly small radiation intensities. Zh. éksp. Teor. Fiz. 113, 1299–1312 (April 1998)  相似文献   
126.
一类三次微分系统的极限环   总被引:1,自引:0,他引:1  
研究一类三次微分系统极限环的个数。给出了极限环的不存在性和唯一性的判别法.后者是利用一条无功二次曲线,它的方程是所论系统的发散量等于零。  相似文献   
127.
Guan J  Yan F  Shi S  Wang S 《Electrophoresis》2012,33(11):1631-1636
A new CE method using sulfobutylether-beta-cyclodextrin (SBE-beta-CD) as chiral additive was developed and validated for the determination of pantoprazole enantiomers. The primary factors affecting its separation efficiency, which include chiral selector, buffer pH, organic additive, and applied voltage, were optimized. The best results were obtained using a buffer consisting of 50 mM borax-150 mM phosphate adjusted to pH 6.5, 20 mg/mL SBE-beta-CD, and a 10 kV applied voltage. The optimized method was validated for linearity, precision, accuracy, and proved to be robust. The LOD and LOQ for R-(+)-pantoprazole were 0.9 and 2.5 μg/mL, respectively. The method is capable of determining a minimum limit of 0.1% (w/w) of R-enantiomer in S-(-)-pantoprazole bulk samples.  相似文献   
128.
Spectra of excitons in a bulk semiconductor and in a thin semiconducting layer are investigated in the two-band Dirac model. The dependences of the exciton binding energy on the energy gap and, in the two-dimensional case, on the layer width are obtained. The fine structures of exciton spectra are revealed.  相似文献   
129.
New experimental evidence is presented which shows that the reliability and the precision of the determination of the optical constants of the metallic and dielectric surfaces can be improved by using the surface electromagnetic wave absorption spectroscopy and SEW phase spectroscopy simultaneously.  相似文献   
130.
The artificial graphite materials were prepared by carbonizing coal tar pitch using two methods, namely, one- and two-step processes, and all sintered samples were graphitized at 2800 °C. Effects of different heat treatments on the performance of the samples were characterized by scanning electron microscopy, transmission electron microscopy (TEM), X-ray diffraction, Brunauer–Emmett–Teller, electrochemical impedance spectroscopy (EIS), particle size analysis, polarized light microscopy, and charge–discharge measurements. All samples show a typical graphite crystalline structure; moreover, the degree of graphitization (g factor) and crystallite size along the c-axis (L c ) were calculated from (002) peak. The polarized light microscopy indicates that the coke with carbonization at 700 °C has an obvious wide domain (D) optical structure, while that with two-step sintering at 400 and 700 °C has a mixed optical structures of wide D, flow domains, and mosaics. TEM analysis revealed a number of irregular graphene layer images which are caused by the defects of graphite. EIS shows that the sample carbonized by two-step has a larger diffusion coefficient than the sample carbonized at 700 °C by one step. Higher carbonization temperature leads to better cycle performance as the temperature increasing from 500 to 700 °C in the one-step route. Specifically, the charge (Li+ extraction) capacity at the 50th cycle increases from 318 mA?h?g?1 to 357 mA?h?g?1. The results show that the rate performance of the artificial graphite is improved with the addition of the presintering at 400 °C.  相似文献   
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