X-ray absorption study of the GeSe system: II. GeSey glasses: Bulk and thin film samples
Abstract EXAFS measurements on Se Ge ratios greater than 2 have been undertaken for different forms of the GeSe y family, bulk or thin films. Data analysis was made both at the Ge and Se K edges and special attention was first paid to the effect of the grain size on the absorption amplitude. The results of the various investigations led to the conclusions that if the germanium tetrahedral environment is constant, that of selenium varies strongly between (i) GeSe 3 and GeSe y , y > 3, and (ii) bulk phases and thin films. A model taking into account these differences is discussed, explaining these changes by the existence of selenium clustering in the more enriched Se compositions.
This article describes screening of fine granular materials, including minerals. The first part of the study presents a description of screening and an analysis of resulting conclusions. The second part describes screens that have been developed in Lodz Technical University labs. From a number of screens only three have been chosen and described in this article. Additionally, results of some pilot-plant-scale tests involving these screens made at Lodz Technical University are discussed. Experimental tests covered first motion of the sieves, and then the process of screening on these sieves. Results are presented both in a graphic form as diagrams and in the analytical form as correlations.