Average path length

The average path length Is equivalent to the diameter of the particle (dp) and thus the number of steps will be equivalent to the column length... 

Tortuosity, 7 Ratio of the column length and the average path length of the channels available to the mobile phase stream and along which diffusion takes place. 

Tortuosity factor or tortuosity x was first introduced by Carman in 1937 [12,13] by reference to a direction that corresponds to a given macroscopic flow. It was defined as the square of the ratio of the "effective average path length" in the porous medium to the shortest distance L measured along the direction of macroscopic flow... 

The larger number of pathways on the PES for small p necessitates a shorter average path length, (5 )p, and a closer separation of minima, (D) in configuration space. Since the average total path length, from a local... 

The tortuosity expresses the average path length a diffusing molecule must travel. In a semicrystalline polymer, it would depend on the crystallinity, crystallite size and shape, and the distribution of crystallites in the amorphous matrix. is a measure of the effective restraint of the motion of polymer chains in the continuous region exerted by the discrete phase. 

As has already been noted, the coefficient of viscosity depends on temperature, but is practically independent of pressure. With increasing temperature, the viscosity of a gas increases, whereas the viscosity of a liquid decreases. This distinction arises because of various mechanisms of momentum transfer in a gas and in a liquid. In a gas, the molecules are relatively far from one another and are characterized by their average path length, 1. Therefore, in a gas... 

The path length distribution of a network tells us how far nodes are from each other. Scale-free networks are ultra-small because they have an average path length of the order log(log N), where N is the number of nodes. Random networks are small because their mean path length is of the order logN. ... 

In this case the porous media can be modeled by an array of N capillaries with the inner radius a and an effective length that differs from L, the actual length of the column. The effective length Le can be understood as the averaged path length of the fluid particles traveling from the entrance to the exit of the column as shown in Fig. 2. Then it is required that the volume AeLe should be the same as the total volume of the porous space, where = Nna is the total cross-sectional area of the collection of the... 

In Eq. (1) we have assumed that the thickness of the sample is the same as the average path length through the sample for the beam of radiation. See Johns" for more discussion. 

An elementary approach frequently used for estimating the increase in the average path length consists of applying a uniform correction factor to all macroscopic cross sections to account for the effective reduction in density due to the presence of the holes. On this basis, it is easy to show that the corrected diffusion length Lh (with holes) is related to the diffu-... 

Both diffusion and advection of solutes are important in biofilms. The biofilm matrix hinders both phenomena obviously the matrix is an effective barrier not only for water movement (advection) but also for the random movement of solutes (diffusion). The effective diffusion coefficient (Deff) is proportional to the biofilm porosity (6) and inversely proportional to the square of the diffusional distance, the average path length (cp) ... 

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