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This paper deals with standard test method for the measurement of vibration-damping properties of materials, ductile cast iron - graphitic cast iron with the spherical shape of graphite. Investigation is focused on its mechanical properties, chemical composition and microstructure, which are necessary as input parameters for computational modeling and numerical analysis. The vibration or oscillating of experimental samples is closely connected with such parameters as natural shapes (eigenshapes) and natural frequencies (eigenfrequencies). Preparation of a geometric model of a homogeneous beam sample and numerical analysis was performed by finite element method in the ADINA software environment. This paper can be used for further development and growth from the aspect of application of computational tools in the area of damping and eigenfrequency properties for construction materials. This paper deal was supported by the Slovak Grant Agency KEGA 007TnUAD-4/2017, VEGA grant No. 1/0649/17, VEGA grant No. 1/0589/17 and resulted from the project “Center for quality testing and diagnostics of materials”, ITMS code 26210120046 relating to the Operational Program Research and Development funded from European Fund of Regional Development

Certain bacteria have motility and can be made non-toxic, and using them for drug delivery has been proposed. For example, using bacteria with flagella motion in multiple spin actuators in drug delivery microrobots has been suggested. This paper investigates various adhesion enhancement methods for attaching bacteria on preferred surfaces of cubic polymeric microstructures to achieve the directional control of motion. Serratia marcescens which has an excellent swimming behavior and 50-μm sized cubic structures made of biodegradable poly-capro-lactone (PCL) are used. Three treatment methods are investigated and compared to the untreated control case. The first method is retarding bacterial attachments by coating certain surfaces with bovine serum albumin (BSA) which makes those surfaces anti-adherent to bacteria. The second and third methods are roughening the surfaces with X-ray irradiation and plasma respectively to purposely increase bacterial attachments on the roughened surfaces. The measured motilities of bacteria-tethered PCL microactuators are 1.40 μm/s for the BSA coating method, 0.82 μm/s for the X-ray irradiation, and 3.89 μm/s for the plasma treatment method. Therefore, among the methods investigated in the paper the plasma treatment method achieves the highest directionality control of bacteria motility.