1,058 research outputs found
Pulse interaction in nonlinear vacuum electrodynamics
The energy-momentum conservation law is used to investigate the interaction
of pulses in the framework of nonlinear electrodynamics with Lorentz-invariant
constitutive relations. It is shown that for the pulses of the arbitrary shape
the interaction results in phase shift only.Comment: LaTeX, 5 pages, 2 EPS figure
Rotational kinetics of absorbing dust grains in neutral gas
We study the rotational and translational kinetics of massive particulates
(dust grains) absorbing the ambient gas. Equations for microscopic phase
densities are deduced resulting in the Fokker-Planck equation for the dust
component. It is shown that although there is no stationary distribution, the
translational and rotational temperatures of dust tend to certain values, which
differ from the temperature of the ambient gas. The influence of the inner
structure of grains on rotational kinetics is also discussed.Comment: REVTEX4, 20 pages, 2 figure
On costa variation in leaves of fossil permian protoshagnalean mosses
Leaves of extinct mosses of the order Protosphagnales are studied with the special attention to their different developmental stages. A previously unknown morphotypes without costa and with very short costa are revealed in this group. It is characteristic for young small leaves of Kosjunia and Intia , but apparently does not occur in other genera of this fossil order. The present collection allows restore a heteroblastic series in these leaves and associated with it differentiation of laminal areolationyesBelgorod State National Research Universit
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