Refractive indices of biaxial crystals evaluated from the refractive indices ellipsoid equation

The expressions of the refractive indices corresponding wave vector k(θ,) are given by using coordinate transformations for the refractive indices ellipsoid equation of biaxial crystals. The refractive index expression of the wave, whose velocity is slower, is given by

and that of the wave, whose velocity is faster, is given by

     

Blow-up of solution of an initial boundary value problem for a generalized Camassa-Holm equation

In this Letter, we study the following initial boundary value problem for a generalized Camassa-Holm equation

     

Superintegrability on N-dimensional curved spaces: Central potentials, centrifugal terms and monopoles

The N-dimensional Hamiltonian

     

Feynman integral treatment of the Bargmann potential

A method based on path integral formulation is given for obtaining exact solution of the s states for the Bargmann potential

     

Energetics of a strongly correlated Fermi gas

The energy of the two-component Fermi gas with the s-wave contact interaction is a simple linear functional of its momentum distribution:

     

Singular ring solutions of critical and supercritical nonlinear Schrödinger equations

We present new singular solutions of the nonlinear Schrödinger equation (NLS)

     

Uniform convergence and the properties of the exponential and generalized exponential integral functions

The exponential integral function (EIF) and the generalized exponential integral function (GEIF) are defined as

     

Radiation transfer in an inhomogeneous half-space

The emergent flux for radiation transfer in an inhomogeneous half-space for a new choice of c(x)

     

A comparative study of the adsorption equilibrium of progesterone by a carbon black and a commercial activated carbon

In this paper the adsorption process of a natural steroid hormone (progesterone) by a carbon black and a commercial activated carbon has been studied. The corresponding equilibrium isotherms have been analyzed according to a previously proposed model which establishes a kinetic law satisfactorily fitting the C versus t isotherms. The analysis of the experimental data points out the existence of two well-defined sections in the equilibrium isotherms. A general equation including these two processes has been proposed, the global adsorption process being fitted to such equation. From the values of the kinetic equilibrium constant so obtained, values of standard average adsorption enthalpy () and entropy () have been calculated. Finally, information related to variations of differential adsorption enthalpy () and entropy () with the surface coverage fraction (θ) was obtained by using the corresponding Clausius-Clapeyron equations.