Antioxidant effect of lignite humic acids and its salts on the thermo-oxidative stability/degradation of polyvinyl alcohol blends

We demonstrate the antioxidant potential of humic acids in (green) polymer chemistry. Lignite humic acids and its sodium and ammonium salts were mixed at different concentrations with polyvinyl alcohol and thermogravimetry was used to assess the influence on the thermo-oxidative stability of resulted blends. Both protonized form and ammonium salt of humic acids caused increased stability of investigated polymers in the studied concentration range (0.5–10% of humic acids in polymer). In contrast to protonized form, the ammonium salt also showed moderating effect on polymer degradation kinetics. Sodium salts caused substantially lower stabilizing effect and presence of 10% of humic matter caused even destabilization. In all cases, however, when the degradation has already started, the presence of humic acids and its salts caused more intensive polymer decomposition, which resulted in lower weight of char.     

Lead isotopes in environmental sciences: a review

Lead (Pb) isotopic analyses proved to be a very efficient tool for tracing the sources of local and global Pb pollution. This review presents an overview of literature published on the use of Pb isotopic analyses of different environmental matrices (atmospheric aerosols, lichens, tree rings, peat deposits, lake, stream, marine sediments, soils, etc.). In order to gain more insight, the isotopic compositions of major sources of Pb in the environment as determined by several authors are described in detail. These include, above all, the former use of leaded gasoline, coal combustion, industrial activities (e.g., metallurgy) and waste incineration. Furthermore, this review summarises analytical techniques (especially ICP-MS) used for the determination of Pb isotopes in environmental samples.     

The assessment of the soil–plant-animal transport of the risk elements at the locations affected by brown coal mining

Environmental Science and Pollution Research - The North Bohemian Brown Coal Basin (Czech Republic) is suggested as a source of significant pollution in the surrounding environment with various...     

Mobility and plant availability of risk elements in soil after long-term application of farmyard manure

Crop rotation long-term field experiments were established in 1955 and 1956 at three locations in the Czech Republic (?áslav, Ivanovice, and Lukavec) differing in their climatic and soil physicochemical properties. The effect of long-term application of farmyard manure and farmyard manure + NPK treatments on plant-available, easily mobilizable, potentially mobilizable, and pseudo-total contents of arsenic (As), cadmium (Cd), copper (Cu), lead (Pb), and zinc (Zn) contents in soils (in 2013) as well as the uptake of these elements by winter wheat (Triticum aestivum L.) grain and straw were analyzed in the two following seasons: 2012 and 2013. The treatments resulted in increasing the soil pH level when compared to the control, but the cation exchange capacity remained unchanged. Although all fertilizers were applied for six decades, the pseudo-total concentration elements in both the soil and wheat plants stayed far below those of the Czech and European threshold limits for agricultural soils and cereals for human nutrition and feedstuff. Although the mobile pools of As, Cu, and Zn were slightly changed at the treated soils, these changes were not related to the element uptake by the wheat plants. Moreover, the effect of the location and growing season was more decisive for the differences in soil and plant element contents than for the individual treatments. Thus, the long-term application of farmyard manure did not result in any substantial change in risk element contents in both soils and winter wheat plants.     

Environmental assessment of RAMseS multipurpose electric vehicle compared to a conventional combustion engine vehicle

The RAMseS project, financed by the European Commission under the 6th framework Program, has the purpose of developing a solar powered agricultural vehicle in order to replace the conventional vehicles based on internal combustion engines (ICE). In the present study, we report a comparison of life-cycle emission between two systems; a conventional ICE vehicle (ICEV) and the RAMseS electrical vehicle (EV). The study has been conducted by designing a specific model and using the SimaPro software. The results show that the RAMseS system is considerably more environmentally friendly than conventional ICE based system and that, specifically, it can avoid the emission of about 23 ton of CO_2equ per year. Regarding all other pollutants, we found that the RAMseS system is 2.6 times more efficient than the ICEV. The main contribution to emissions of the RAMseS system is due to the batteries which contribute for a 73% of the total. Therefore, further improvement can be obtained with the use of more advanced battery systems, not based on lead.