On the equation of diffusion in a turbulent medium

The two-dimensional form of the equation of diffusionu∂χ∂x=∂∂zAz∂χ∂z(z>0),under steady mean conditions in a fluid moving with mean velocityuis discussed in the ease where u andA_zvary asz^mandz^1-mrespectively (0 <m< 1). Integrals are constructed which satisfy boundary conditions of the types arising in physical problems, and the results are applied to the theory of evaporation into a turbulent atmosphere.