Morphology,microstructure and chemical composition of single inhalable particles in Shanghai,China

The morphology, microstructure, and chemical composition of a variety of particles emitted from coal-fired power plants, steel plants, and vehicle exhausts, which are possible sources of particulate matter (PM) in the atmosphere, were investigated by scanning electron microscopy (SEM) and transmission electron microscopy (TEM) and compared with particle samples collected from urban atmosphere to identify the best footprint or the suitable indicator relating the existence of studied particles and their possible emitters by the morphology, microstructure, and chemical composition of the particles. The investigation indicated that the particles from these three sources are different in morphology, microstructure, and chemical composition. Sphere aggregates were generally the most abundant components, with silicon and aluminum as major elements. The urban air particulate contained particles similar to those observed in the power plant, steel plant, and vehicle exhaust samples suggesting that all three sources are contributing to the pollution in the city.     

Efficient oxidation of sulfides into sulfoxides catalyzed by a chitosan–Schiff base complex of Cu(II) supported on supramagnetic Fe<Subscript>3</Subscript>O<Subscript>4</Subscript> nanoparticles

Sulfoxides are versatile synthetic intermediates for the preparation of biological products. Therefore, there is a need for efficient methods to oxidize sulfides into sulfoxides. Such oxidation may be catalyzed by magnetic nanocatalysts due to their good stability, easy synthesis, high surface area, low toxicity and easy separation by magnetic forces. Here we prepared a nanocatalyst by immobilization of the chitosan–Schiff base complex on supramagnetic Fe₃O₄ nanoparticles. The chitosan–Schiff base complex has been previously prepared by functionalization of chitosan with 5-bromosalicylaldehyde and metalation with copper(II) acetate. The catalyst was characterized by Fourier transform infrared, powder X-ray diffraction, transmission electron microscope, scanning electron microscopy, energy-dispersive X-ray spectroscopy and thermogravimetric analysis. Results show that the Fe₃O₄ nanoparticles and nanocatalyst were spherical in shape with an average size of 20 nm. Upon the covalently anchoring of chitosan–Schiff base Cu complex on the magnetic Fe₃O₄ nanoparticles, the average size increased to 60 nm. The prepared Fe₃O₄–chitosan–Schiff base Cu complex catalyzed very efficiently the oxidation of sulfides to sulfoxides with 100 % selectivity in all cases under green reaction conditions and excellent yields. Additionally, ease of recovery and reusability up to four cycles without noticeable loss of catalytic activity make the present protocol beneficial from industrial and environmental viewpoint.     

A review on efficient electromagnetic interference shielding materials by recycling waste—a trio of land to lab to land concept

Environmental Science and Pollution Research - The materials used in electrical and electronic applications have great importance and broader applications, but they have severe electromagnetic...     

Anticancer properties of medicinal plants and their bioactive compounds against breast cancer: a review on recent investigations

Environmental Science and Pollution Research - Breast cancer (BC) is one of the most common and recurring diseases and the second leading cause of death in women. Despite prevention, diagnostics,...     

Pilot-scale electrokinetic treatment of a Cu contaminated red soil

A pilot-scale experiment for electrokinetic treatment of 700 kg of copper contaminated red soil was conducted using a constant voltage of 80 V. Dynamic removal percentages of Cu from the soil and energy consumption during the treatment were evaluated together with changes of soil pH, electrical conductivity and soil microbial functional diversity before and after the electrokinetic treatment. The results indicate that 76% of Cu was successfully removed from the soil after 140 d of treatment when lactic acid was used as enhancing reagent for adjusting the catholyte pH and dissolving soil Cu by complexation, and the pilot-scale electrokinetic experiment consumed electric energy of 224 kW h t-1 soil. The post-treatment soil pH values decreased about 0.1-1.6 units compared with the initial value (pH 4.8), and soil electrical conductivities in most of soil sections also significantly decreased. Soil microbial functional diversity varied after the electrokinetic treatment, particularly the increase of substrate richness index, which is possibly due to the stimulation of lactic acid that was introduced into the soil column during the experiment.     

Photocatalysis: an effective tool for photodegradation of dyes—a review

Environmental Science and Pollution Research - The disposal of dye-contaminated wastewater is a major concern around the world for which a variety of techniques are used for its treatment. The...