Even though mechanical activation is a significant pretreatment technology for the efficient extraction of metals from mineral resources, its effects on bioleaching sphalerite and marmatite are rarely discussed. In this study, using various grinding media times was conducted, particle size distribution, morphology, X-ray diffraction (XRD) energy dispersive spectrometry (EDS) analyses, as well b...

The article deals with the influence of vibrations for accuracy and durability machine tools. Main content involves use technical diagnostics, which includes vibrodiagnostics. Vibrodiagnostics is applied directly in technological manufacturing process. Technological process machining rough grinding steel balls. Using vibrodiagnostics, information recorded, are further evaluated. evaluation obta...

.\BSTR.\ CT A brief summary of the limited literature devoted to mud balls centers around nomenclature, the ideas regarding the origin of mud balls, and the factors limiting their size. A report is made of a combined field and laboratory study in which an investigaticn of the size which mud balls may attain leads to conclusions that differ from those in the literature; findings are presented wh...

We consider the well-known problem of randomly allocating m balls into n bins. We investigate various properties of single-choice games as well as multiple-choice games in the context of weighted balls. We are particularly interested in questions that are concerned with the distribution of ball weights, and the order in which balls are allocated. Do any of these parameters influence the maximum...

This paper introduces the concept of critical ball. Critical balls are maximal balls which are necessary and sufficient to describe and rebuild sets, contrary to maximal balls where some redundancy exists. A general definition of a critical ball is given in continuous spaces and some of its main properties are depicted. Thanks to a slight modification of their definition, critical balls can als...