This contribution presents four dye-based CONs derived from the reaction of triformylphloroglucinol with thionin acetate (RIO-43), safranin chloride (RIO-51), phenosafranin (RIO-47), and Bismarck brown Y (RIO-55). These materials, called Covalent Organic Networks (CONs), are insoluble solids formed by organic lamellar stacked structures and present permanent porosity, light absorption across the whole visible spectrum, fluorescence, ion exchange capability, and ion and electron conductivity. Periodic DFT calculations carried out indicated that the bent nature of most of those building blocks affords conductive extended materials containing pores with the shape of three-petal flowers, with the anion positioned at the petals. The turbostratic disorder makes only the center of the flower-shaped pores accessible, decreasing the specific surface areas. The material that has a higher surface area is the one derived from thionin acetate (RIO-43), such as the highest electrical conductivity (1.96 × 10 -5 S cm −1 ), followed by RIO-47 (1.12 × 10 -7 S cm −1 ), RIO-55 (1.58 × 10 -7 S cm −1 ) and RIO-51 (3.26 × 10 -7 S cm −1 ).
Coarse particulate matter (PM 10) concentrations and chemical composition were monitored from 2014 to 2017 at three sampling sites in the Metropolitan Region of Rio de Janeiro, namely Botafogo, Gávea, and Gericinó. All sites are located close to the 2016 Olympic Game arenas. The average annual PM 10 concentrations were above the limits recommended by the World Health Organization (WHO) at all sampling sites. Of all the analyzed water-soluble ions, the highest concentrations were obtained for NO 3 − , SO 4 2− , Cl − and Na +. Sulfate displayed a higher anthropic contribution (ca. 70%). Iron and copper were present in all samples, originated from soil resuspension and traffic (fuels and brakes, among others). Overall, civil works to restructure the city and the construction of the Olympic Game arenas increased PM 10 and some of its constituent levels prior to 2016. After the Olympic Games, PM 10 concentrations have decreased, due to governmental policies regarding traffic planning and civil work finalization.
ASSESSMENT OF THE CONCENTRATION AND INORGANIC COMPOSITION OF PARTICULATE MATTER COLLECTED IN THE STATE OF RIO DE JANEIRO. Cities urbanization and modernization increase emission sources, contributing to particulate matter (PM) composition heterogeneity and enhance the risk to human health and environment. This paper intends to survey the studies on particulate matter carried out in the state of Rio de Janeiro. The sampling of PM is generally made using Hi-Vol samplers to collect particles in fiberglass filter during 24 h every 6 days. Spectrometric techniques are used for elemental determination and ion chromatography for water-soluble species. The Environmental State Institute (INEA) is responsible for air quality monitoring in RJ. After 30 years, air quality standards have become more stringent and have included new pollutants. The highest PM concentrations were found in urban and industrial sites and the lowest in places away from urban activities or near the coast. Over the years, PM concentrations near steel complexes reduced even below the limits and varied at other places, remaining above the limits. Nitrate and sulfate were the main ionic compounds, and Fe, Al and Zn were the major elements in PM samples. It was also found Ni, V, Cd, Pb and Cu. Although air quality monitoring is efficient, it still needs to be improved to help reduce the environmental impact.
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