Sources of error in the X-ray fluorescence analysis of powders, particularly of iron ores. Reasons for the use of TlOwdered and compacted ore samples in the X-ray fluorescence analysis. Discussion of the sources of error when analysing iron ore powders, such as grain size, effect of matrix and crystal structure. Use of Kiruma and Minette ores for the examination with a hand-operated single-my fluorescence apparatus. Instructions for carrying out the analysis on the basis of the investigation results. Use of comparable samples of very similar composition in order to overcome the difficulties.
A. WATILLON, F. VAN GRUNDERBEECK et M. HAUTECLER (Bruxelles)
SUMMARYHydrophobic selenium colloidal solutions prepared by Kruyt and Van Arkel's method were found to contain a large range of particle size, when verypure water was used. Moreover results were irreproducible. This is probably due to low and irregular nuclei content of the reagents used.By reducing the selenium oxide in presence of gold amicrons very homeodisperse and reproducible sols were obtained.The ionic content of the sols has been determined by a conductometric method. The sols were purified by electrodialysis using an original set up in which the water was continuously purified by ion exchange resins incorporated into the apparatus itself.
A. WATILLON et M. HAUTECLER (Bruxelles)
SUMMARYAn apparatus for the dark field microelectrophoresis is described. The illumination is obtained by a lateral slit-system according to Mackor. We used a cylindrical thick-walled cell without introducing errors due to multiple refractions of the incident light beam.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.