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Sulfur dioxide (SO(2)) is used as a preservative and stabilizer in wine production to prevent undesired biochemical processes in the must and the final product. The concentration of SO(2) is restricted by national regulations. There are two main forms of SO(2) in wine-free (inorganic forms) and bound (fixed to organic compounds, e.g. aldehydes). Iodometric titration is commonly employed for determination of SO(2) concentration (either by direct titration or after pre-separation by distillation); other techniques are also used. In this work inductively coupled plasma-optical-emission spectrometry with vapour generation was used for determination of free and total SO(2) in wine. Gaseous SO(2) is released from the sample by addition of acid and swept into the ICP by an argon stream. The intensity of the sulfur atomic emission lines is measured in the vacuum UV region. Determination of total SO(2) is performed after hydrolysis of bound forms with sodium hydroxide (NaOH). Concentrations of acid for vapour generation and NaOH for hydrolysis were optimised. The method was used for determination of free and total SO(2) in red and white wine samples and results were compared with those from iodometric titration.

This article presents the development of selected heavy metals contained in river sediments at selected sites along the Bílina River. It describes the situation before the large flood in 2013, the situation just after that flood, the situation approximately 1 year after the flood, and 4 years after the flood. The contents of selected heavy metals from industrial pollution originating from transport and industry located along the river flow were monitored. Since the situation in the river before the flood was also known, it was possible to assess the impact of the 2013 flood on the distribution of heavy metals in the settled sediments. The results obtained show that the heavy metal content has changed significantly. During the flood in 2013 there was an increase in the concentration of almost all the monitored elements compared to the situation before the flood and one year after the flood. This could be caused by the churning of sediments as a result of the flood. The only exception was Cd, the concentration of which did not change significantly. However, Cd is present in the sediment samples at a low concentration at the limit of quantification (LOQ), so the change may not be noticeable. In 2017, four years after the flood, an increase in the concentration of all the monitored elements was found. The highest increase in the content of the monitored elements was observed at the sites with the highest industrial pollution. Following the flood in 2014, there was a situation where no significant differences were observed in the content of metals at the individual sampling points in contrast to the values obtained in 2012, 2013, and 2017. As a result of sediment churning and re-settlement during and after the flood, the sediment became homogenized along the entire river flow. After a longer period of time that was not accompanied by floods, a significant increase in the heavy metal concentration was observed due to anthropogenic pollution. The results show that the effect of flooding is only temporal and that anthropogenic pollution is more important than the impact of floods.

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Thermal stability of organic coatings for aluminum plays a key role not only in specific applica-tions, but also in the recycling process of aluminum scrap. For production of secondary alumi-num it is necessary to remove coatings from scrap. Rests of unremoved coatings affect the qual-ity of final aluminum. Most of methods for coatings removing are based on thermal decomposi-tion. This process leads to emission of various organic compounds which present potential risk for human health and also for environment. Thermal stability of all tested coatings with in-creasing temperature was study with use of thermogravimetric analysis (TGA). Significant deg-radation of coating started at temperature 200 °C and at temperature 450 °C was most of the tested coating degraded and remained only inorganic part of coating. Inorganic part render ap-prox. 30 % of the original coating mass. Degradation of tested coatings was also confirmed by Fourier transform infrared spectroscopy (FTIR) analysis. This work also deals with study of in-organic/organic ratio of hybrid coating on real sample of scrap for recycling. The thermolabile part of coating is degraded during heating, which lead to emission of organic compounds and products of degradation which can affect human health and also the environment.

Abstract. This paper presents a study of the immobilization of humic substances (HSs) on a polypropylene (PP) nonwoven fabric. In order to attach the HSs, the PP nonwoven fabric was modified in a volume of nonthermal atmospheric pressure dielectric barrier discharge (DBD) under defined conditions. An unmodified PP nonwoven fabric was used as a reference sample. The modified and unmodified samples were both dipped in an aqueous solution of potassium humate, and then the samples were washed in water and the amount of HSs attached to the PP fabric was monitored. An aqueous solution of cadmium salts was filtered through the treated fabric, the content of Cd 2+ in the solution was monitored using ICP-OES analysis, and the Cd 2+ sorbed on the fabric was proved by SEM/EDS analysis. The efficiency of the PP plasma modification was proved by XPS analysis, and the presence and the distribution of the HSs along the fibers was proved by SEM analysis.