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Nanoparticles of TiO2 are suitable for many catalytic and photocatalytic applications due to their extraordinary properties such as superhydrophobicity, semiconductivity, electron-rich, and environmental compatibility. The main crystalline phases of TiO2, anatase, and rutile possess different crystal structures, crystallinity, crystalline sizes, and specific surface areas, and these characteristics directly affect the catalytic performance of TiO2. In the present study, domestic carbon material enhanced with TiO2 nanoparticles was synthesized and used for the construction of a modified carbon paste electrode. The electrocatalytic activity of the modified electrodes was investigated depending on the TiO2 crystalline phases in the electrode material. Furthermore, the obtained working electrode was utilized for triclosan detection. Under optimized experimental conditions, the developed electrode showed a submicromolar triclosan detection limit of 0.07 µM and a wide linear range of 0.1 to 15 µM. The relative standard deviations for repeatability and reproducibility were lower than 4.1%, and with satisfactory selectivity, the proposed system was successfully applied to triclosan monitoring in groundwater. All these results confirm that the sustainable production of new and domestically prepared materials is of great benefit in the field of electrocatalysis and that the morphology of such produced materials is strongly related to their catalytic properties. [ABSTRACT FROM AUTHOR]

The aim of this study was to investigate the degradation of the non-ionic surfactant Triton X-100 (TX-100) by using an advanced oxidation process in a non-thermal plasma reactor based on water falling film dielectric barrier discharge (DBD). The effects of two catalytic plasma systems, Fe2+/DBD and H2O2/DBD, were tested to improve the degradation of TX-100 and the mineralization efficiency in the DBD reactor. Both catalytic systems exhibited significant improvements in degradation efficiency, especially in the beginning of the treatment: the efficiency increased from 23 to 88 and 50%, for 5 mg L−1 Fe2+/DBD and 10 mmol L−1 H2O2/DBD, respectively. The mineralization efficiency of TX-100 in the non-catalytic DBD treatment was very low (1%), but with addition of catalysts, the mineralization efficiency was drastically improved, with H2O2/DBD at 4-34% (depending on the H2O2 concentration) and Fe2+/DBD at 2-21% (depending on the Fe2+ concentration). Degradation products of TX-100 in non-catalytic and two catalytic systems were identified using UHPLC-Orbitrap-MS. Based on the degradation products that were identified, a simple mechanistic scheme was proposed. MS analysis revealed that degradation of TX-100 in the DBD reactor occurred by shortening the ethoxy chain. In the presence of catalysts, there are additional reactions of cleavage of the alkyl chain followed by formation of polyethoxylated phenol (H2O2/DBD) and addition of OH• radicals onto the aromatic ring (Fe2+/DBD). The final degradation products did not cause any significant toxic effects to Vibrio fischeri or Artemia salina. [ABSTRACT FROM AUTHOR]

The aim of this paper was the development and optimization of an electrochemical method for the degradation of two triketone herbicides, mesotrione, and sulcotrione, in a two-electrode undivided electrochemical cell equipped with commercially available, non-modified, electrode materials. The electrochemical parameters studied included five different electrode systems (Zr/Pt, Pd/Pt, C/Pt, Nb/Pt, and Ti/Pt), current densities (27.66, 55.33, ..., 110.66 mA · cm−2) and pH values (3, 7, and 9) in 0.05 M sodium sulfate as supporting electrolyte. The electrical energy consumption and chemical oxygen demand were calculated for optimal conditions. The degradation efficiency was determined by high performance liquid chromatography (HPLC) equipped with a diode array detector, while the degradation products for both pesticides were identified and compared by ultra-high performance liquid chromatography (UHPLC)-mass spectrometry. The results could lead to an accurate estimate of their effect on the environment. A real water sample was used to study the influence of organic matter on pesticide degradation. Based on the results obtained the electrochemical treatment could be used for the successful removal of triketone herbicides from contaminated water. [ABSTRACT FROM AUTHOR]

Electrochemical treatment is a new trend for the purification of textile industry wastewater which containing azo dyes. In this paper the electrochemical treatment was used for decolorization of azo dye Reactive Blue 52. The efficiency of decolorization was compared for different electrochemical systems which were all equipped with Fisher platinum electrode as anode and a different cathode (Zr, Pd, C) in sodium sulfate as supporting electrolyte. In order to find optimal conditions the influence of various voltage and pH values of initial dye solution was studied. Decolorization rate was monitored by spectrophotometer while degradation products were identified by high performance liquid chromatography-diode array detector (HPLC-DAD). Results of HPLC analysis confirmed presence of various degradation products in electrochemical systems, which indicated different mechanism of degradation. This was also confirmed by Ek- t curve. In terms of power consumption the most cost effective system was with the graphite cathode (C/Pt). [ABSTRACT FROM AUTHOR]

The aim of this study is to investigate the significance of breast milk and infant formula in the prevention of oxidative stress, by electrochemical determination of the total antioxidant potential, demonstrating the relationship between the antioxidant capacity of milk and postnatal age. Human breast milk, commercial UHT milk, and infant formulas supplemented with prebiotics were used. Samples were diluted in phosphate buffer solution, and the total antioxidant activity was potentiometrically measured by the iodine/iodide redox couple with the Pt Fisher electrode as a working electrode and saturated calomel as a reference electrode. Cyclic voltammograms and differential pulse voltammograms were recorded with the glassy carbon electrode as the working electrode, an accessory platinum electrode, and an Ag/AgCl reference electrode. The potentiometric measurement indicates that human breast milk has the highest redox potential, while the commercial UHT milk has very low potential. Infant formulas also have high potential. The main advantage of electrochemical methods used to assess the total antioxidant activity of milk was that they directly monitored the electron-donating ability of the compounds and could be used for the quantitative analysis of the total antioxidants of different types of milk. [ABSTRACT FROM AUTHOR]

Infrared thermography, or thermovision, is getting more and more applicable in sport and sport rehabilitation. Thermovisional method is fast, efficient, and with technology development it is getting more and more available. In this paper thermovisional method is used to improve kendo training process. Kendo is Japanese martial art with sword. Kendo training is specific. With termovision we can show correct posture and practice with sword. [ABSTRACT FROM AUTHOR]