We study the diffusion process of a Brownian particle moving in a one-dimensional ratchet with space-dependent friction that is subjected to an external source. The equation of motion for a particle involves a multiplicative fluctuation, a nonlinear friction and an external driving force or a...

The paper reports measurements of the viscosity of normal butane and isobutane at atmospheric pressure in the temperature range 25–195°C. In addition, the viscosity of mixtures of the two gases has been determined in the more limited temperature range 25–100°C. The absolute accuracy of the...

The paper reports on new, accurate (±0.3%) measurements of the viscosity of binary and multicomponent mixtures involving the four saturated hydrocarbons: CH4, C2H6, C3H8 and C4H10. Measurements were restricted to atmospheric pressure and the temperature range 25–195°C.