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Abstract

At present, industrial development is increasing pollution of soils, air and natural waters. These pollutants have a negative effect on the health and life of living organisms. Metals which interfere with the natural biological balance and inhibit self-cleaning processes in water bodies have particularly toxic effects. Cobalt, which gets into the environment from industrial sewage from electrochemical plants and the metallurgical industry, also belong to this group. This is also relatively rare and precious element, so it is important to look for additional sources of its recovery. Chemical and physicochemical methods such as: precipitation, extraction, membrane processes – nanofiltration, reverse osmosis, sorption and ion exchange are used to recover cobalt. The choice of method depends on: the kind and composition of wastewaters as well as on form and concentration of the pollutants. Ion exchange resins produced by Purolite which were used to remove cobalt ions from solutions with concentrations corresponding to its contents in galvanic wastewater was the subject of the study. It has been shown that the C 160 ion exchange resin has the best the sorption properties for Co2+ ions (54.7 mg/g). In case of this ion exchange resin, after sorption process carried out in one 50 minute cycle, cobalt concentration decreased from about 30 g/L to about 9 g/L. The values of the sorption capacity do not depend on the method of introducing the solution into an ion exchange column (pouring or dropping). E ach of the tested ion exchange resins is characterized by a high degree of cobalt concentration after regeneration using mineral acids, which can be advantageous in selecting the recovery method for this metal.
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Abstract

The aim of the author is to present some messianic and prophetic ideas, which are intrinsically fused with Karl Marx’s doctrines, and which had also been expressed in Jewish mystical thought as well as in the ethical message of the Bible. Although Marx did not obtain any proper Jewish education, he was not able to reject his own being-a-Jew or his inborn spirituality together with the implicit axio-normative system of Judaism. Marxist philosophy, generally speaking, is dominated by the postulate of building a better and a more just world, and by the ethical demand of creating a new reality, from which poverty and social marginalization would be eradicated. However, such views were not new. For, it was the author of the Biblical “Book of Devarim”, who earlier emphasized the need for social solidarity. There had also been some Jewish prophets who criticized kings and priests, and Tsfat Jewish mystics who had formulated an ethically radical tikkun ha-olam postulate in the 16th century.
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Abstract

Screw axis measurement methods obtain a precise identification of the physical reality of the industrial robots’ geometry. However, these methods are in a clear disadvantage compared to mathematical optimisation processes for kinematical parameters. That’s because mathematical processes obtain kinematical parameters which best reduce the robot errors, despite not necessarily representing the real geometry of the robot. This paper takes the next step at the identification of a robot’s movement from the identification of its real kinematical parameters for the later study of every articulation’s rotation. We then obtain a combination of real kinematic and dynamic parameters which describe the robot’s movement, improving its precision with a physical understanding of the errors.
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