Efficiency wall curvature

The Effect of Curvature of the Separator Wall on the Efficiency Coefficient... 

Thus, the curvature of walls may noticeably influence the CE of the separator only at rather high flow velocities, where the efficiency of separation is small. Since this velocity interval does not present any practical interest, one can conclude that for practical calculations the separator can be modeled by a container with rectangular cross section. 

The size, structure, and fluidity of membrane lipids are also important because those aspects of the molecules make it possible for them to pack efficiently into a variety of convoluted bilayer membrane structures with various degrees of curvature and flexibihty. Tliat flexibility also makes possible the inclusion of the various other important components of the cell wall, including proteins, carbohydrates, and cholesterol. In terms of the geometric concepts discussed previously (see Fig. 15.15), one can visualize where one class of lipid will have a critical packing factor. Pc (= v/adc) < 1, which will produce a truncated cone shape, while another will have F > i for an inverted truncated cone. Combinations of the two can then accommodate the inclusion of, for example, proteins and cholesterol, while maintaining an overall planar structure (or a given degree of curvature), or increase curvature to produce a smaller associated unit. 

The above analysis was first adopted by Shen, Zeng, and Lee (2005) to compare the nucleation efficiency of nanoparticles of different geometry (single-waUed carbon nanotubes, carbon nanofibers, and clay nanoparticles) in polystyrene foams. They found that consistent with the theoretical prediction, among the three nanoparticles studied, the single-walled carbon nanotubes exhibited the lowest nucleation efficiency because of the smallest size and curvature. Carbon nanofibers have the highest nucleation efficiency and nanoclays (with flat surface) have an efficiency in between. 

Size, structure, and fluidity of membrane lipids are also important characteristics because those aspects of the amphiphilic molecules make it possible for them to efficiently pack into a variety of bilayer membrane structures with various degrees of curvature and flexibility. That flexibility makes possible the inclusion of other important components of the cell wall, including proteins, glycoproteins, and cholesterol. 

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