Mantas Pranskevičius

Investigation and evaluation of carbon dioxide emissions from soil in Neris Regional Park

Abstract. Soils release around 20% of the total CO2 content to the atmosphere; consequently, forest and agricultural ecosystems have a big influence on CO2 balance. Until recently, the majority of CO2 measurements of Lithuanian soils were either carried out under laboratory conditions or obtained by applying outdated research methods. CO2 investigations in Neris Regional Park were carried out under field conditions during plant vegetation by using the CO2 emission measuring instrument ADC BioScientific and soil chamber, the analysis system of which includes a metal collar of ∼0.9 m2 area. This infrared gas analysis system performs measurements within the range of 0–2000 ppm, with an error of 1 ppm. The emissions error is a mere ±2%. The system allows making reliable measurements within the temperature range of −5 °C to +50 °C.

Experimental research into aerodynamic parameters of a cylindrical one-level 8-channel cyclone

AbstractThe Environmental Protection Laboratory of Vilnius Gediminas Technical University has developed and installed a one-level 8-channel cyclone with different internal structure, which is used for separation of particulate matter from air streams. Airflow velocity was measured in five points of each channel: at the end and the beginning of the channel, in the middle of the channel and in points arranged at 45° angle from the channels end and beginning. The highest airflow velocity determined in 8-channel device by regulating volumes of peripheral and transit airflows with curvilinear semi-rings was in cyclones channel 1, while the lowest – in channel 2. Contrary to the above, the highest airflow velocity in 8-channel cyclone by using quarter-rings without holes and with 5° opening angle of plates in holes was recorded in channel 2. Tests on aerodynamic resistance were carried out in airflow inlet and outlet ducts. In all cases analysed the highest aerodynamic resistance in 8-channel cyclone was dete...