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H W Hsu

Publications and source records attributed to H W Hsu.

41 records · Page 3Linked to original sources
PubMed1969

Transport phenomena in zonal centrifuge rotors. II. A mathematical analysis of the areas of isodensity surfaces in reorienting gradient systems.

Zonal centrifuges may be loaded during rotation (dynamically) or at rest (statically). In the latter case, the shearing forces occurring in a liquid confined in a closed cylinder, during the transition from rest to a stable orientation in a high centrifugal force field, were examined qualitatively by evaluating the change of surfaces in each isodense layer. Analytical expressions for isodense surfaces at various levels were obtained as a function of the rotational speeds. Characteristics of the changes of each isodense layer were computed from the formula derived and are presented, in a graphical form, as figures. From these results, an optimal sample-loading location and an ideal control of acceleration or deceleration in a reorienting gradient rotor are concluded.

Centrifugation, Zonal↗
PubMed1968

Transport phenomena in zonal centrifuge rotors. I. Velocity and shear-stress distributions of fluid during acceleration.

An analysis is presented for the evaluation of velocity components and shear-stress distributions of fluid in zonal centrifuge rotors during acceleration. Analytical expressions for the distribution of tangential and radial velocity components and the tangential shear-stress and the radial shear-stress distributions of fluid are obtained for the transient case. Characteristics of each distribution for a typical density gradient liquid in a zonal centrifuge rotor are computed from the relations derived, and are presented as figures. An unusual phenomenon-the tangential velocity of the gradient exceeding the velocity of the rotor during a particular period of acceleration-is demonstrated.

Centrifugation, Zonal↗