Reduction of Organic Compounds by Lithium Aluminum Hydride. I. Aldehydes, Ketones, Esters, Acid Chlorides and Acid Anhydrides

TLDR: In this article, the length and molecular weight of the particles as determined by the light scattering measurements are used with a value of 0.73 for the partial specific volume of the virus, the diameter of the cylindrically shaped virus particles can be calculated to be 15.2 mp.

Abstract: weight-average molecular weight of M = 40 X 106 with a probable error of 5%. In this determination of the molecular weights from light scattering no assumptions need be made about the percentage of hydration of the particles. If the length and molecular weight of the particles as determined by the light scattering measurements are used with a value of 0.73 for the partial specific volume of the virus, the diameter of the cylindrically shaped virus particles can be calculated to be 15.2 mp. This value is in agreement with that obtained in X-ray'22 and electron microscope16 studies. Summary Light scattering measurements were made on a freshly prepared sample of purified tobacco mosaic virus. The length of the particles determined from dissymmetry of light scattered by the solutions were found to be 270 mp. Application of the dissymmetry to turbidity measurements gave a weight average molecular weight of 40 millions for the particles. These values are in complete agreement with sizes determined from electron microscope and viscosity studies made on the same sample. This agreement indicates the validity of the light scattering method. For dilute solutions of tobacco mosaic in water the dissymmetry decreases with increasing virus concentration thus indicating that strong interaction with a consequent increase in order of the scattering particles is occurring. However, the dissymmetry is independent of concentration for dilute solutions of the virus in 0.1 M sodium phosphate buffer a t pH 7.