Currently, scientists are still looking for new polymeric materials characterized by improved mechanical, thermal as well as dielectric properties. Moreover, it should be stressed that new composites should be environmentally friendly. For this reason, the aim of this work is to establish the influence of natural fillers in the form of diatomaceous biosilica (B) and talc (T) on the properties of dielectric elastomer (DE)-based composites. The dielectric elastomer-based materials have been tested taking into account their morphology, thermal and mechanical properties. Moreover, the dielectric constant of the obtained materials was evaluated. Obtained results revealed that the presence of both diatomaceous biosilica and talc significantly increases dielectric properties while having no significant effect on the mechanical properties of the obtained composites. It should be stressed that the performed analyses constitute a valuable source of knowledge on the effective modification of the thermal and dielectric properties of newly obtained materials.

The aim of this work involved comparing the effect graphite and shungite have on the properties of dielectric elastomer-based materials. For this reason, dielectric elastomer–Sylgard (S) was filled with 1, 3, 5, 10, and 15 wt.% of graphite (G) and shungite (Sh). The structure of the obtained materials was studied by means of scanning electron microscopy and atomic force microscopy. The influence of the introduced additives on the thermal stability of the obtained composites was evaluated using thermogravimetry. Moreover, the mechanical properties and the dielectric constant of the elastomer with an addition of graphite and shungite were determined. Obtained results allowed us to establish that the presence of graphite as well as shungite significantly influences mechanical as well as dielectric properties. Additionally, the optimum mass of additives, allowing to increase the dielectric constant without the significant decrease of strain at break, was indicated. In the case of materials containing graphite, regardless of the filler content (1–15 wt.%), the mechanical as well as the dielectric properties are improved, while in the case of composites with an addition of shungite exceeding the 5 wt.% of filler content, a reduced tensile strength was observed.

The article describes the use of multi-criteria optimization methods during the calibration of digital multimeters. Currently, calibration is based on a single measurement of a specific value. The aim of this research was to confirm the possibility of using a series of measurements in order to reduce the measurement uncertainty without significantly extending the calibration time. The automatic measurement loading laboratory stand used during the conducted experiments was essential to obtain results that allowed confirming the thesis. This article presents the applied optimization methods and the results of the calibration of sample digital multimeters obtained thanks to them. As a result of the research, it was found that the use of a series of measurements increased the accuracy of the calibration, reduced the measurement uncertainty, and shortened the calibration time compared to traditional methods.

Diagnostics in ballast water management is the main remedy to protect against the threat of spreading invasive species that can be carried in ships' ballast tanks. This phenomenon is getting better known and understood. New and more effective methods of preventing threats related to this are being developed. Procedures are created to ensure environmental safety in the face of ever-increasing transport by sea. The article characterizes both the background of the problem, basic diagnostic medics used in ballast water management, as well as procedures and basic techniques used to ensure the safety of the natural environment..