Resolution and tonal continuity in bilevel printed picture quality

Bilevel printing of continuous tone pictures has the potential to be effectively perfect when the contrast information in a picture matches or exceeds the capacity of the eye to make use of it. Useful pictures may be printed with much lower information content provided that the reduction is compatible with the characteristics of the visual system. A review of these requirements provides a framework for the examination of published bilevel printing schemes. From this conclusions are drawn concerning the best scheme to use under various printing constraints

Vacuum evaporation from finite surfaces

It is known that the evaporation rate is equal to the rate of phase transition only when the evaporating surface is small or when a condensing surface is placed very close to the evaporating surface. This paper describes a quantitative theory which predicts the rate of evaporation from a finite surface into a vacuum in the absence of such a condenser or other nearby surfaces. The predictions of the theory for finite surfaces have been confirmed by comparison with experimental data reported in the literature and, in the limiting case of an infinite surface, with the predictions of a previous theoretical study

SOME ASPECTS OF THE KINETICS OF REDUCTION OF CHROMITE WITH CARBON.

Sundar Murti and Seshadri published the results of a laboratory study of the kinetics of reduction of synthetic chromite with carbon. The purpose of this note is to provide additional references to other studies which complement the paper