The phenomenological theory of sedimentation describes a flocculated suspension as a mixture of the solid and the fluid as two superimposed continuous media. Starting from the mass and linear momentum balances for each component, this theory yields, through constitutive assumptions and an order-of-magnitude analysis, three coupled partial differential equations describing the sedimentation–cons...

1. Fibrin clots prepared in the absence of calcium can be dissolved in solutions of lithium chloride and bromide and sodium bromide and iodide, as well as of guanidine hydrochloride and urea. These salts do not denature fibrinogen under the same conditions of concentration, temperature, and time. Sedimentation experiments on the fibrin solutions show in each case a single sharp peak with a sedi...

Envelope-associated nucleoids have been isolated from Caulobacter crescentus by using a modification of the procedure of T. Kornberg et al. (Proc. Natl. Acad. Sci. U.S.A. 71:3189-3193, 1974). The development of a Ludox density gradient procedure has permitted preparation of large quantities of synchronous cells. The sedimentation coefficients of the envelope-associated nucleoids of stalked and ...

Human isoforms of nucleoside diphosphate kinase, NDPK-HA and NDPK-HB, have been expressed in E. coli and purified. Their apparent molecular masses have been determined by FPLC gel filtration. Absolute molecular masses were measured by equilibrium ultracentrifugation and sedimentation coefficients determined from the sedimentation velocity. Under near-physiological conditions, NDPK-HA has a mass...

1. Sedimentation and diffusion measurements have been made in the concentration range 0-170O8 g./100 ml. on human serum albiumins obtained by ethanol fractionation and by electrophoretic separation. 2. The effect of variation in composition of the buffer has been examined with the result that, for a given preparation, sedimentation or diffusion may be affected at finite concentrations, but valu...

A bacterial exopolysaccharide from Aphanothece halophytica GR02 (AH-EPS) solubilised in buffered 1 M guanidine hydrochloride, GuHCl was studied using capillary viscometry, double gap viscometry, sedimentation velocity and sedimentation equilibrium using analytical ultracentrifugation. Results from capillary viscometry indicate that the exopolysaccharide is xanthan-like in its shear thinning pro...

Under ionic conditions effecting little or no subunit dissociation, Chlamydomonas reinhardi contains 2 major classes of ribosomes with generic sedimentation velocities of 83 and 70s and 3 minor classes with sedimentation velocities of 66, 54, and 41 s. Ribosomal RNAs with sedimentation velocities of 25, 23, 18, 16 and 5 s have been identified. The 70-sribosomes are in the chloroplast and contai...