Nowadays, pollen allergy becomes an increasing problem for human population. Common mugwort (Artemisia vulgaris L.) is one of the major allergenic plants in Europe. In this study, the influence of air pollution caused by traffic on the structure and chemical composition of common mugwort pollen was investigated. Scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), and curve-fitting analysis of amide I profile was applied to assess the morphological and structural changes of mugwort pollen grains collected from sites with different vehicle pollution levels. Microscopic observations support the conclusion, that the higher the car traffic, the smaller the pollen grains. The obtained results clearly show that air pollution had an impact on different maximum absorbance values of individual functional groups composing the chemical structure of pollen. Moreover, air pollution induced structural changes in macromolecules of mugwort pollen. In pollen collected from the unpolluted site, the content of sporopollenin (850 cm−1) was the highest, whereas polysaccharide concentration (1032 cm−1) was the lowest. Significant differences were observed in lipids. Pollen collected from the site with heavy traffic had the lowest content of lipids at 1709, 2071, and 2930 cm−1. The largest differences were observed in the spectra regions corresponding to proteins. In pollen collected from unpolluted site, the highest level of β-sheet (1600 cm−1) and α-helix (1650 cm−1) was detected. The structural changes in proteins, observed in the second derivative of the FTIR spectrum and in the curve-fitting analysis of amide I profile, could be caused inter alia by air pollutants. Alterations in protein structure and in their content in the pollen may increase the sensitization and subsequent risk of allergy in predisposed people. The obtained results suggest that the changes in chemical composition of pollen may be a good indicator of air quality and that FTIR may be successfully applied in biomonitoring.

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Nowadays pollen allergies become an increasing problem for human population. Mugwort ( Artemisia vulgaris) and hazel ( Corylus avellana ) are major herbaceous allergenic plants in Europe [1‐3]. In this study the effect of vehicle pollutants on the structure and chemical composition of mugwort and hazel pollen were investigated. For this purpose pollen of the respective plants were collected from three sites with different vehicle pollution level. Scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR) and curve‐fitting analysis of amide I profile was performed to assess the structural changes of mugwort and hazel pollen. SEM imaging did not reveal any differences in shape or any physical degradation of the hazel (Fig. 1a, b) and mugwort (Fig. 1c, d) pollen grains collected from the different sites. It was found that infrared spectra look the same for pollen collected at sites with high traffic pollution. Conversely, they differ a lot from spectra of respective pollen types collected from sites without pollution. Moreover, structural changes in proteins, observed in the second derivative of the FTIR spectra and in the curve‐fitting analysis of amide I profile, are a consequence of mutations occurring in the genetic material of pollen, which can be caused inter alia by air pollutants [4]. The results suggest, that mugwort and hazel pollen chemical composition may be a good indicator of air quality and FTIR may be applied in biomonitoring.

Nowadays limited resources of fossil fuels and environmental concerns increase interest in alternative sources of energy [1]. Recently, fuel cells became very popular and interesting as a good solution for this problem. However, it should be remembered that the oxidation reaction between the catalyst and the fuel (ethanol) occurring in fuel cells is complex and generates a lot of by‐products. This whole process does not promote a better efficiency of the cell, on the contrary, it leads to poisoning of the catalyst, decreasing the efficiency of the device. Therefore the key challenge for this branch of science is primarily the development of the appropriate type of catalysts [1]. Recently promising technology seem to be ternary nanocatalysts containing platinum, rhodium, and tin oxide (IV) [2]. The motivation for our work is a better understanding of the synergistic effect between these three components in nanocatalysts, replacing the rhodium by rhenium and determining their selectivity for total oxidation of ethanol to CO 2 .In the present study we used three methods of synthesis: polyol [3], citrate [4] and microwave assisted [5]. The obtained nanoparticles were characterized by Photon Correlation Spectroscopy (PCS), Transmission Electron Microscopy (TEM) and Fourier Transform Infrared Spectroscopy (FTIR). The HAADF STEM structural analysis showed that the nanoparticles obtained by all three methods have similar dimensions ‐ about 2 nm. In the case of the citrate and polyol methods the nanoparticles were strongly agglomerated, which was visible not only in the TEM images, but also confirmed by the results obtained by the PCS. On the other hand, nanoparticles obtained by the microwave assisted synthesis did not show such a strong agglomeration as those obtained by the two other methods. All SnO 2 samples had a crystalline structure, which was confirmed by HRSTEM images (Fig. 1). Additionally fourier transform infrared spectroscopy (FTIR) was applied to determined the structure of tin oxide obtained in the two differences synthesis (microwave and polyol assisted). It was found, that in the infrared spectrum of Sn oxide synthesized by polyol methods, a stretching modes of Sn‐O from Sn(OH) 4 was not observed. Moreover, in this samples, more stretching modes of O‐Sn‐O (Sn 4+ ) was noticed, whereas the samples synthesized by microwave methods, characterized by larger amounts of Sn‐O (Sn 2+ ) stretching modes (Fig. 2). The size of the nanoparticles varied from 2 to 12 nm, depending on the synthesis parameters. The next step is the synthesis of PtRh and PtRe nanoparticles on the obtained SnO 2 supports. Our research confirmed that the crystalline structure, particle size and shape, and surface properties are highly dependent on the chosen method of synthesis.

Nowadays, nanoparticles with sizes between 2 to 50 nm become more and more popular, because they can be applied in various fields such as materials science, chemistry, catalysis, medicine or biology. In particular nanoparticles with fancy shapes gain a lot of attention, also because of the low‐cost synthesis methods. This study is focused on several types of catalytic nanoparticles (NPs), silver nanoparticles synthesized using green chemistry methods and in particular on their morphological and chemical analysis using HR(TEM). Three‐dimensional (3D) catalysts [1] being promising for application in fuel cells were studied. These nanoparticles have a dodecahedron shape with Pt skin at the edges and a Ni core, Figure 1(a). When etching away the core, the remaining empty Pt frame offers a much larger active surface compared to spherical nanoparticles. The morphology of these 3D PtNi particles strongly depends on the synthesis parameters allowing fabricating dodecahedrons, Figure 1(a), core‐shell or even dendritic structures, Figure 1(b). SnO 2 nanoparticles are excellent supports for noble metal NPs, as their combination exhibits good catalytic activity towards ethanol oxidation reaction [2]. Various synthesis routes including polyol and microwave assisted methods allowed producing different SnO 2 NPs, Figure 2(a). The break of the C=C bond in the ethanol molecule occurs at the interface between PtRh and SnO 2 particles, Figure 2(b). Therefore their physical contact is imperative for the effectiveness of the catalyst. Structural aspects and chemical analysis by TEM characterization techniques of the PtRh/SnO 2 /C catalysts were analyzed. Green synthesis method using camomile extract was applied to synthesize silver nanoparticles in order to tune their antibacterial properties merging the synergistic effect of camomile and Ag [3]. Scanning transmission electron microscopy (STEM) revealed that camomile extract (CE) consisted of porous globular nanometer sized structures, which were a perfect support for Ag nanoparticles, Figure 3(a). The Ag nanoparticles synthesized with the camomile extract (AgNPs/CE) of 7 nm average size, were uniformly distributed on the CE support, Figure 3(b). The EDX chemical analysis showed that camomile terpenoids, Figure 3(c) act as a capping and reducing agent being adsorbed on the surface of AgNPs/CE, Figure 3(d), enabling their reduction from Ag + and preventing them from agglomeration. Antibacterial tests using four bacteria strains, showed that the AgNPs/CE performed five times better compared to CE and AgNPs/G samples, reducing totally all the bacteria in 2 hours, Figure 4.