|PETRÁŇ Aleš||Technical University of Liberec|
|Spoluautoři KROISOVÁ Dora|
The aim of this study is the characterization of selected natural composite systems created as organic-inorganic materials. The study is focused on the characterization of the structure and chemical composition of these systems and on the evaluation of basic mechanical parameters of selected samples too. The detailed description is presented for the structure of sea shells, which are created by interconnected layers of micron crystals and submicron plates of calcium carbonate. These systems were evaluated by scanning electron microscopy, EDX analysis and microhardness. Typical structure of nacre is known like a typical arrangement but the arrangement is different for other types of shells. Individual building blocks can be found with the dimensions of complying with the definition of nanostructured materials too. The arrangement of the crystal exhibits a recurring motive - crystals are characterized by their shape, mostly pentagons and hexagons, but also the diameter, height and thickness. Difference between the layers as well as their interconnection is characteristic for different kinds of shells. The aim of the structure and the chemical composition study is the effort to obtain all necessary information for constructing similar systems for use in practice. ACKNOWLEDGEMENTS: The results of this project LO1201 were obtained through the financial support of the Ministry of Education, Youth and Sports in the framework of the targeted support of the “National Programme for Sustainability I” and the OPR&DI project Centre for Nanomaterials, Advanced Technologies and Innovation CZ.1.05/2.1.00/01.0005.