We investigate a nonlocal reaction-diffusion-advection equation which models the growth of a single phytoplankton species in a water column where the species depends solely on light for its metabolism. We study the combined effect of death rate, sinking or buoyant coefficient, water column depth and vertical turbulent diffusion rate on the persistence of a single phytoplankton species. Under a ...

We present a self-consistent mean field theory of the dynamo in 3D and turbulent diffusion in 2D in weakly ionized gas. We find that in 3D, the backreaction does not alter the beta effect while it suppresses the alpha effect when the strength of a mean magnetic field exceeds the critical value Bc ∼ √ νinτn〈v2〉/Rm. Here, νin, τn, and Rm are ion-neutral collision frequency, correlation time of ne...

Introduction ______________________________ Disposal of radioactive wastes in streams. Radioactivity budget in streams. ________ Characteristics of radioactive wastes which are discharged into streams______________________________ Sources of wastes.__--__--_--_-_-_______________ Nature of wastes.--__-------___-_______________ Properties and types of radionuclides________ Chemical and physical c...

We investigate diffusion in supersonic turbulent compressible flows. Supersonic turbulence can be characterized as network of interacting shocks. We consider flows with different rms Mach numbers and where energy necessary to maintain dynamical equilibrium is inserted at different spatial scales. We find that turbulent transport exhibits superdiffusive behavior due to induced bulk motions. In a...

An unsteady flamelet model, which will be called the Lagrangian Flamelet Model, has been applied to a steady, turbulent CH4/H2/N2–air diffusion flame. The results have been shown to be in reasonable agreement with experimental data for axial velocity, mixture fraction, species mass fractions, and temperature. The application of three different chemical mechanisms leads to the promising conclusi...