background and aims. dental handpiece is a source of contamination because it is in constant touch with the oral cavity. sterilization does not seem to be sufficient to prevent penetration of microorganisms into air and water lines of the unit, because negative pressure developed by valves (which are placed in water outlets) and post shut-off inertial rotation of handpiece result in water and d...

PURPOSE The assessment of the indoor air and walls contamination of fungi at the Kavala Hospital in Greece was made. MATERIAL AND METHODS The study was carried out at the Neonatal Department and Intensive Care Unit and Palliative Care in Kavala Hospital (Greece). Materials for the tests were: the air samples (in front of the building and the selected rooms) and swabs from the walls. The air p...

-In storm waterways and at dam outlets, high-velocity supercritical flows are characterized by substantial air bubble entrainment. The entrainment of fine air bubbles and the strong turbulent mixing contribute both to the air-water transfer of volatile gases (e.g. oxygen, nitrogen, VOC). The paper describes new experimental data obtained in a 25 m long channel with a 4 ° slope. The analysis of ...

Water resources for irrigation can be difficult to obtain specially in the arid regions. However, for high humidity areas such as places close to the sea, water can be condensed from the air. In this paper we build water condensation system based on thermoelectric cooler. The system consists of cooling elements, heat exchange unit and air circulation unit. A solar cell panel unit with a relevan...