Fick's First Law states that the diffusion flux is proportional to the concentration gradient. It can be expressed as: \[ J = -D \frac{dC}{dx} \] where \( J \) is the diffusion flux, \( D \) is the diffusion coefficient, \( C \) is the concentration, and \( x \) is the position.
Fick's Second Law describes the time dependence of the concentration distribution and is given by: \[ \frac{\partial C}{\partial t} = D \frac{\partial^2 C}{\partial x^2} \] This law is particularly important for understanding how the concentration of nanoparticles evolves over time in a given medium.
