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Uraniferous bitumens found in black shales from the Permian rocks at Vrchlabí in the Krkonoše Piedmont Basin (Czech Republic) were described and characterized petrologically and mineralogically. The Permian sediments originated from weathering products in metasediments and granitoids of the Krkonoše–Jizera and Orlice–Sněžník crystalline complexes. The organic matter contained up to 4.8 wt.% uranium, as uraninite grains. Elements associated with uraninite, such as Pb, Zr, Cu, and As, may have accumulated from epigenetic fluids in layers rich in organic matter during their late diagenesis. The bitumen structures were extremely heterogeneous, a feature attributed to the radiolytic effects of uranium. Amorphous bitumens, alternating with various forms of nodular and corroded bitumen types from multiple generations, were present. Low and highly altered bitumens with weak anisotropy were recognized, together with halo zones, with reflectance up to 4.37%. The halo zones differed in size, brightness, and reflectance, increasing from the edge to the center. Halos often revealed dark rims between uraninite inclusions and clear zones, originating probably as a result of weaker alterations in organic matter due to the presence of other inorganic components. Uranium concentration was the main factor controlling the degree of radiolytic alteration. The studied uraniferous bitumens are an excellent example of multistage formation and diverse evolution during burial and diagenesis.

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Dosimetry of high doses of ionizing radiation is a method widely used not only in the field of basic and applied research but also in various industries. High-dose irradiation is used in the sterilization of foodstuffs and prolongation of their shelf life, sterilization of tools, materials and wastewater, treatment of antiquities attacked by woodworm organisms, biological and genetic research, inhibition of seed germination and retardation of fruit ripening. Furthermore, it has been applied in radiation resistance testing of materials, defectoscopy, industrial irradiation of materials (e.g. crosslinking and grafting of polymers or gemstone coloring by ionizing radiation), and last but not least, of course, nuclear energetics. In this work the dosimetric properties of polycarbonate are studied. They are compared with a standardized and certified method using alanine dosimeters. In the case of gammas the testing was realized for 60Co and neutron radiation was studied in the research nuclear reactor LVR-15.