Abstract: The conception of buckling relative initial imperfection is presented in this paper. According to Bernoulli-Euler beam equation, the dynamic buckling mode of an elastic bar under the homogeneous boundary conditions can he derived by applying the preferred mode analytical method. As an example, the dynamic buckling mode of an elastic bar clamped at both ends is discussed.

Key words: nanoparticles, Brownian coagulation, collision efficiency, Stokes resistance, lubrication force