EVALUATION OF AN ENERGY HARVESTING MR DAMPER-BASED VIBRATION REDUCTION SYSTEM

The paper deals with an MR damper-based vibration reduction system with energy harvesting capability. The main part of the system creates an MR damper and a power generator based on an electromagnetic transduction mechanism, which are integrated into a stand--alone device (so called energy harvesting MR damper). The main objective of the work is to evaluate performance of the proposed vibration reduction system employed in a single DOF mechanical structure. The material outlines the design structure and characteristics of the energy harvesting MR damper, presents the vibration reduction system based on this damper and explores experimental testing of the system implemented in a single DOF mechanical structure. To demonstrate that the devised system is feasible, performance figures maps completed by experimental data are shown

CHANGES OF FLUORIDE CONTENT IN SAND FROM SANDBOXES LOCATED ON PLAYGROUNDS IN POLICE (WEST POMERANIA, POLAND)

The aim of the study was to determine fluoride content in sand from sandboxes in Police town (West Pomerania, Poland). This area is exposed to excessive emissions of fluoride compounds because of the proximity of chemical plants. The sand samples were collected five times in a period from March to November in 2016. Fluoride content was determined using the potentiometric method with an ion-selective fluoride electrode. The obtained results showed that fluoride content was ranged from 0.09 to 1.48 mg·kg-1 dm. The lowest fluoride content was recorded in the sand collected in place, which was the closest to the emitter, and the largest in the samples from sandbox, which was furthest from the emitter. Analyzing the changes in the content of this element over time, the largest fluoride concentration of sand occurred in July or September depending on location. Pearson correlation coefficient at p < 0.05 (r = 0.925) showed a significant positive correlation between fluoride content and the distance from fluoride emitter

CHANGES OF FLUORIDE CONTENT IN SAND FROM SANDBOXES LOCATED ON PLAYGROUNDS IN POLICE (WEST POMERANIA, POLAND)

The aim of the study was to determine fluoride content in sand from sandboxes in Police town (West Pomerania, Poland). This area is exposed to excessive emissions of fluoride compounds because of the proximity of chemical plants. The sand samples were collected five times in a period from March to November in 2016. Fluoride content was determined using the potentiometric method with an ion-selective fluoride electrode. The obtained results showed that fluoride content was ranged from 0.09 to 1.48 mg·kg-1 dm. The lowest fluoride content was recorded in the sand collected in place, which was the closest to the emitter, and the largest in the samples from sandbox, which was furthest from the emitter. Analyzing the changes in the content of this element over time, the largest fluoride concentration of sand occurred in July or September depending on location. Pearson correlation coefficient at p < 0.05 (r = 0.925) showed a significant positive correlation between fluoride content and the distance from fluoride emitter