• LIDAR MONITORING OF AIR POLLUTION OVER URBAN AREAS COMBINED WITH IN-SITU SAMPLING OF PARTICULATE MATTER

    Machines. Technologies. Materials., Vol. 12 (2018), Issue 10, pg(s) 412-414

    The object of this investigation was the synergy effect achieved by combining lidar monitoring of particulate matter (PM) pollution in atmospheric aerosol over urban areas (city of Sofia) with in-situ sampling. The lidar systems of the Laser Radar Laboratory (LRL) of the IE-BAS were used to scan at two laser wavelengths the horizontal and vertical aerosol distributions and long-distance transport. The results demonstrated the possibility of detailed fast remote monitoring and analysis of the air pollution over entire urban regions, providing fast estimates of the air pollution transport over the city, as well as detection of sources of extreme emissions. Once the place of high PM concentration was localized by the lidar, samples were taken using a Hygitest 106 (Maimex) – a high-efficiency portable device for sampling and concentration determination of PM in atmospheric aerosol. The data presented pertains to the winter period 2018 year. PM pollutions than 10 and 2.5 μm were under studied. The lidar maps created can be further used for tracing the full air mass transport carrying contaminations from various pollution sources (chemical, biological, dust, etc), distributed over the scanned region. Further, the sampling schedule was conformed with the seasons of the year, in order to reveal any characteristic seasonal hazardous microbial contamination.

  • MATERIALS

    NEW IRON OXIDES/HYDROXIDES BIOMATERIALS FOR APPLICATION IN ELECTRONICS AND MEDICINE

    Machines. Technologies. Materials., Vol. 10 (2016), Issue 12, pg(s) 48-51

    Biotechnologies could supply inexpensive, environment friendly and effective materials for new nonstandard and concurrent solutions. The present work’s focus was on acquiring new physical data for application in electronics and medicine of biogenic materials obtained due to the metabolism in laboratory conditions of iron-oxidizing bacteria from the genus Leptothrix. Powders and coatings on glass samples were under investigation. XRD and Raman Spectroscopy analysis of the data collected show that the Fe2+-depending from the growth media could transformed into Fe3+ or Fe2.5+ in the form of two types of oxides/hydroxides such as magnetite (Fe3O4) and lepidocrocite (ɣ-FeOOH), all with nanostructured morphology. Biotechnology for obtaining one biogenic iron phosphate hydroxide (ferrian giniite) – (Fe5(PO4)4(OH)3.2H2O) was also developed. The ferrian magnetic material is dispersed in the walls of biogenic tubular structures.
    The average particle’s size and crystalline structures of bio-products were investigated. Results based on PPMS measurements on the magnetic properties were reported. The new biogenic materials showed superparamagnetic behaviour and high sensitivity to electromagnetic radiation and have real potential for application in electronic and information technologies.