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The nonlinear propagation of dust-ion-acoustic (DIA) solitary waves (SWs) in an unmagnetized four-component dusty plasma containing electrons and negative ions obeying vortex-like (trapped) velocity distribution, cold mobile positive ions and arbitrarily charged stationary dust has been theoretically investigated. The properties of small but finite amplitude DIASWs are studied by employing the reductive perturbation technique. It has been found that owing to the departure from the Maxwellian electron and Maxwellian negative ion distribution to a vortex-like one, the dynamics of such DIASWs is governed by a modified Korteweg–de Vries (mKdV) equation which admits SW solution under certain conditions. The basic properties (speed, amplitude, width, etc.) of such DIASWs are found to be significantly modified by the presence of trapped electron and trapped negative ions. The implications of our results to space and laboratory dusty electronegative plasmas (DENPs) are briefly discussed.

Compared with the other wireless communication band, X-ray carrier has the merits of lower wavelength, higher frequency and photon energy, which could provide a novel method to solve the communication problems of re-entry blackout region. In this paper, transmission characteristics of X-ray carrier in the re-entry dusty plasma medium were analyzed first, simulation results indicate that dusty particles were more likely to impede the microwave signal than X-ray carrier. Then an alkali metal plasma source was designed to simulate the re-entry dusty plasma sheath for simplification. Transmission co-efficiency under different X-ray energy were tested, which pointed out that X-ray signal would obtain more than 79.4% transmission co-efficiency on condition of dynamic and dusty plasma medium. Finally, we give our proposal and potential capability of X-ray communication in the re-entry plasma condition.

Both the linear and the nonlinear magnetosonic wave in a multi-component dusty plasma are studied in the present paper. The dependence of the dispersion relation of the linear waves on the dust size distribution are given. It seems that the larger the difference between the maximum and the minimum radius of the dust grains, the lower the wave frequency for all cases of the dust size distribution. Furthermore, it is noted that the width, the amplitude and the propagation velocity of the KdV solitary wave depend on the dust size distribution, especially it depend on whether the number density of the larger sized dust grain is larger or smaller than that of the smaller sized dust grain. For the power law dust size distribution, the width and the propagation velocity of the KdV solitary wave between the maximum and the minimum radius of the dust grains is larger than that of mono-sized dusty plasma.

By using the PIC simulation method and theoretical investigation from both the magnetohydrodynamic equations and the Vlasov equation of the dusty plasma produced by the relative streaming of the dust fluid and the background ionospheric plasma, we investigate the instability of the waves excited by this kind of the dust beam in the ionosphere. It is found that the waves are stable in both the electron and ion vibration time scales, while they are unstable in the dust grain vibration time scale. It is inferred that the wave is the high hybrid wave in the electron vibration time scale. The dispersion relations of the perturbed waves in both the electron vibration and ion vibration time scales are obtained. As the time increases until it arrives at the dust grain vibration time scale, the instability appears for the perturbed wave. Such instabilities may drive plasma irregularities that could affect radar backscatter from the clouds, when the wave satisfies the Bragg condition for backscatter. By using the dispersion relation of waves in both electron vibration and ion vibration time scales, we can infer what kind of radar backscatter can be possibly affected by the instability of the perturbed waves.

New aspects of collective nonlinear dust plasma interactions are presented. These are the formation of dust ion-acoustic shocks and Langmuir envelope solitons in a uniform dusty plasma, as well as self-organization of incompressible dust fluid in the form of vortical structures in a nonuniform dusty plasma. We present relevant nonlinear models and their numerical simulations for those nonlinear waves and structures. The relevance of our investigation to laboratory and space dusty plasmas is discussed.