When mineral processing separation results, for either constant or varying quality of the feed, can be approximated on the so-called Fuerstenau upgrading plots with the same one-fitting parameter a, then this parameter can be used as a selectivity indicator. If the equation has a form [...], where [...] stands for recovery of non-useful component in tailing while\ksi is the recovery of useful component in the concentrate, then at the same selectivity of upgrading (constant a) the increase of the useful component in the feed \alfa results in an increased amount of this component in both concentrate \beta and tailing [...] while the ratio of [...] to \beta is linearly dependent on \alfa when \epsilon is constant. Thus, at a constant selectivity a and constant \epsilon an increase in \alfa leads to a greater increase of the considered component in the tailing \theta than in the concentrate \beta.

In the present article the author describes the issue of relation between Synagogue and Church in the context of Johannine writings. The author makes analysis of the Johannine texts in order to show the traces of polemic between Judaism and Christianity. He shows the hostility between Synagogue and Church in the light of terms like aposunagōgos, “Jews” and other polemical expressions which occur in the Gospel of John, in the Letters of John and the Book of Revelation. The author tries to answer the question of how Sitz im Leben of the Johannine writings influences their content. The analysis of Jewish and Christian sources shows the tension and hostility between Rabbinic Judaism and Johannine Community after the destruction of the Jerusalem Temple. It leads to gradual separation between Synagogue and Church. In this article there are shown the reasons for the parting of the ways between Judaism and Christianity and its meaning for the contemporary dialogue between Synagogue and Church.

The coal fed to gravity enrichment consists of coals coming from different deposits and exploitation fronts. These coals differ in quality parameters, especially the amount of gangue (stone) changing over time. This results in the instability of work, especially jiggers, which have a relatively low accuracy assessed by probable scattering or imperfection rates. This deteriorates the quality of the concentrate obtained, the quality parameters of which change over time. The improvement of jiggers work would be possible by averaging the feed. This process is practically impossible due to the failure to design such a node during plant construction, which are, in most cases, directly related to the shaft. In the article, the authors propose to solve the process of averaging the feed before directing it to the enrichment process in jiggers by introducing its deshaling in vibratory- air separators of the FGX type.