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In this work, the electrochemical behaviour and the subsequent development of an analytical procedure for quantification of pesticide azamethiphos, using boron-doped diamond (BDD) electrode are reported for the first time. It was found that azamethiphos electrochemical behaviour is irreversible oxidation at the potential of around 1.70 V, in 1 M nitric acid (pH 0). Also, it was found that potential of this oxidation was not pH dependent which can be attributed to the no proton involvement in electrochemical reaction on the electrode surface. The square wave voltammetric method was most appropriate for azamethiphos quantification. Under optimised experimental conditions, linear working range from 2 to 100 µM was estimated with the detection limit of 0.45 µM. Negligible effect of the possible interfering compound was observed. The obtained results show that the developed analytical methodology can be an adequate replacement for the, up to date, used methods for detection of organophosphorous pesticide. © 2018, © 2018 Informa UK Limited, trading as Taylor & Francis Group.

In this work, for the first time we proposed electrochemical behavior and development of an analytical procedure for quantification of pesticide clomazone. Electrochemical behavior of clomazone's at boron-doped diamond electrode is characterized with irreversible oxidation at potential of around 1.6 V, in Britton-Robinson buffer solution at pH 2. It was found that potential of this oxidation was not pH dependent excluding presence of proton in the electrochemical reaction. Square wave voltammetry method was the most appropriate for clomazone quantification and proposed procedure was successfully applied for determination of clomazone in river water samples. Obtained parameters, detection limit of 0.21 mu M and working linear range from 1 to 100 mu M and satisfied selectivity can indicate that presented results open new field in research of this group of pesticides and offer possible replacement to the sophisticated and expensive chromatographic methods.

This paper presents an experimentally-proved hydrometallurgical process for selective metals recovery from the waste-printed circuit boards (WPCBs) using a combination of conventional and time-saving methods: leaching, cementation, precipitation, reduction and electrowinning. According to the results obtained in the laboratory tests, 92.4% Cu, 98.5% Pb, 96.8% Ag and over 99% Au could be selectively leached and recovered using mineral acids: sulfuric, nitric and aqua regia. Problematic tin recovery was addressed with comprehensive theoretical and experimental work, so 55.4% of Sn could be recovered through the novel physical method, which consists of two-step phase separation. Based on the results, an integral hydrometallurgical route for selective base and precious metals recovery though consecutive steps, (i) Cu, (ii) Sn, (iii) Pb and Ag, and (iv) Au, was developed. The route was tested at scaled-up laboratory level, confirming feasibility of the process and efficiencies of metals recovery. According to the obtained results, the proposed hydrometallurgical route represents an innovative and promising method for selective metals recovery from WPCBs, particularly applicable in small scale hydrometallurgical environments, focused on medium and high grade WPCBs recycling.

Pethoxamid (POA) is relatively new herbicide and it belongs to group of chloroacetamides. It inhibits the germination of target weeds in corn, soybeans, peas and beans, tobacco and other crops and it can affects on herbicide-resistant weeds. There are no many research records about this, in the future quite applicable, herbicide. Bearing in mind that pethoxamid is high soluble in water, with almost no sorption in soils [1], the leaching and runoff of this compound in ground and surface water is a real threat. Pethoxamid residues in soil, water food and feed of plant origin usually were determined by using liquid chromatography with tandem mass spectrometry (LC–MS/MS) [2] while some other analytical methods were used for determination of pesticides [3]. The electroanalytical methods are noted as fast and cost-effective analytical methods for determination of many analytes of environmental interest. As far as we know, this is a first report about electrochemical behavior of herbicide pethoxamid and its electroanalytical determination. This method is based on the electrochemical oxidation of pethoxamid in Britton-Robinson buffer solution at pH 4 at a boron-doped diamond electrode. This type of carbon electrode is almost resistant to contamination of surface with various chemical spaces, easy to maintain and has a very wide working potential window which could provide insight into the electrochemical oxidation of pethoxamid at high anodic potentials. All electrochemical measurements (cyclic and square-wave voltammetry) were performed on PalmSens 3 potentiostat/galvanostat/impedance analyzer with PSTrace software (PalmSens BV, Netherlands). Three-electrode system in the electrochemical cell was consisted from Ag/AgCl (1M KCl) reference electrode and platinum wire counter electrode, while working electrode was boron-doped diamond electrode. BDD electrode was electrochemicaly prepared as it was written before [4]. Cyclic voltammetry provided a well defined oxidation peak a

The new complex [Zn2(tpmc)NO3](NO3)3·CH3OH, where tpmc is N,N’,N’’,N’’’-tetrakis(2-pyridylmethyl)-1,4,8,11-tetraazacyclotetradecane, have been synthesized and characterized. The conductometric technique played a guiding role in planning experiment with this large macrocyclyc ligand. In IR spectrum sharps are shown coordinated and ionic nitrate ions which are in agreement to proposed formula by elemental analysis. Molar electrical conductivities indicated assumption that the complex is about a 1:3 electrolyte type. The optimized complex structure is obtained by molecular modeling and DFT calculations.

Photo and nuclear radiation induced processes are considered through the interaction of radiation with semiconducting, metallic and other materials, including the scintillator materials. The improvement of component efficiency by the use of quantum generators, trimming and hybrid processes with nuclear radiation has been analyzed. The studied processes can be positive or negative depending on application. Besides the experimental approach to the processes and chosen interactions, the analytical description of our experiments, as well as ones from other references, has been performed. The contemporary couplings between the nuclear physics, laser techniques and respective dosimetric aspects have been considered.