ISSN:
0006-3525
Schlagwort(e):
Chemistry
;
Polymer and Materials Science
Quelle:
Wiley InterScience Backfile Collection 1832-2000
Thema:
Chemie und Pharmazie
Notizen:
In connection with our goal of calculating by practical methods the frictional properties of biopolymers from surface shells composed of spheres, we have investigated by the method of reflections the low-Reynolds-number hydrodynamic interaction between two unequal-sized spheres in translation. Previous results, in which the velocities were used as independent variables and which have the form of truncated infinite power series, were substantially extended. By inversion of the power series, new power series with better convergence properties were obtained. Equivalence of these inverted power series with those previously reported based on the method of reflections, when forces are used as independent variables, was demonstrated, and the solutions were again substantially extended. Applying the Lagrange interpolation to data generated from exact theories for the hydrodynamic inteaction between two spheres, it was demonstrated that the various forms of the method of reflections do not just give reasonable power series, but actually yield optimal ones. These findings constitute a unification of diverse approaches and show methods of interconversion of results. On the basis of the power series obtained, a set of new hydrodynamic interaction tensors for two unequal spheres were derived. While the new tensors described the case of two unequal spheres with considerably more accuracy than those previously reported, direct application of these tensors to objects composed of more than two spheres revealed some unexpected problems resulting from overcorrection in the fourth-order term. However, when the tensors were preaveraged over all orientations of the multisphere object, a formula for the scalar translational friction coefficient was obtained that outperformed all but the most involved earlier approaches. It thus constitutes an improved and practical solution to the problem of computing translational friction coefficients of objects describable by a surface shell of many spheres, such as proteins.
Zusätzliches Material:
2 Ill.
Materialart:
Digitale Medien
URL:
http://dx.doi.org/10.1002/bip.360220409
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