The transport and production of the generally non-conserved extensive property of volume V within a flowing gas or liquid is addressed. Specifically, a convective/diffusive/production-type transport equation, ρDmv^/Dt+∇·jv=πv, governing the transport of volume, is derived for the evolution...

Starting from the Boltzmann equation, a new model that describes effectively the diffusion of particle packets through matter has been developed. The model is exhaustively analyzed and all hypotheses, made in its derivation, are discussed. An interesting application to the field of the BNCT is...

We discuss the basic transport phenomena in gases and plasmas obeying the q-nonextensive velocity distribution (power law). Analytical expressions for the thermal conductivity (Kq) and viscosity (ηq) are derived by solving the Boltzmann equation in the relaxation-time approximation. The...

We present a new class of thermal ratchets operating under the action of a symmetry breaking non-Hermitian perturbation which rectifies thermal fluctuations, and driven by an unbiased periodic force. The peculiar non-Hermitian dynamics which follows cause energy transduction from the force to...

The second rank alignment tensor characterizing the preferential orientation of rod-like or disc-like molecules can easily be detected via the birefringence associated with it. The third rank tensor specifying a local short range order with tetrahedral symmetry, as expected for water, on the...

A new application of the percolation theory for describing the coupled heat and mass transport phenomena through porous media is given. The space and time dependence of the temperature and moisture level functions are calculated by taking into account the discrete, sudden changes of the...