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This study introduces a novel photoelectrocatalytic (PEC) system featuring a Ti-O-Cu mixed nanotubular oxide photoanode for the simultaneous activation of peroxymonosulfate (PMS), targeting the removal of emerging contaminants, such as methylene blue dye, tetracycline, and ibuprofen. The Ti-5.5Cu (atom %) alloy substrate and the nanotubular oxide layer were synthesized through arc melting and electrochemical anodization. The conditions of photoelectrocatalysis-assisted PMS activation (PEC/aPMS) were optimized using experimental design, achieving 90.4% decolorization of methylene blue dye within 30 min under optimal conditions: pH 4, an applied potential of 0.5 V vs Ag/AgCl, and a PMS concentration 50 times the molar concentration of the contaminant, utilizing a 10 W UV LED at 365 nm. In contrast, only 25% decolorization was observed without PMS. Singlet oxygen ( 1 O 2 ) was identified as the primary pathway for PMS activation (nonradical). Additionally, the PEC/aPMS system effectively degraded model contaminants, achieving 52% degradation of ibuprofen, 78% of methylene blue, and 92% of tetracycline in 10 mg L -1 total organic carbon solutions within 60 min under optimized conditions. The electrode exhibited remarkable stability, maintaining its efficiency throughout the experiments. These findings highlight the potential of mixed nanostructured oxide electrodes for developing highly efficient and durable PEC systems with integrated PMS activation for the removal of organic contaminants., Competing Interests: The authors declare no competing financial interest., (© 2024 The Authors. Published by American Chemical Society.)

In many countries, water quality monitoring is limited due to the high cost of logistics and professional equipment such as multiparametric probes. However, low-cost sensors integrated with the Internet of Things can enable real-time environmental monitoring networks, providing valuable water quality information to the public. To facilitate the widespread adoption of these sensors, it is crucial to identify which sensors can accurately measure key water quality parameters, their manufacturers, and their reliability in different environments. Although there is an increasing body of work utilizing low-cost water quality sensors, many questions remain unanswered. To address this issue, a systematic literature review was conducted to determine which low-cost sensors are being used for remote water quality monitoring. The results show that there are three primary vendors for the sensors used in the selected papers. Most sensors range in price from US$6.9 to US$169.00 but can cost up to US$500.00. While many papers suggest that low-cost sensors are suitable for water quality monitoring, few compare low-cost sensors to reference devices. Therefore, further research is necessary to determine the reliability and accuracy of low-cost sensors compared to professional devices.

This article presents an analysis of possibilities for electrical energy production by using municipal solid waste disposed in the biggest Brazilian cities. Currently, the municipal solid waste in Brazil is collected and disposed of at landfills, but there are also other technologies, which in addition to dealing with the garbage can also provide benefits in terms of energy provision. The following scenarios were studied in this work: electricity production from landfill gas (reference scenario); incineration of all municipal solid waste; anaerobic digestion of organic waste and incineration of refuse-derived fuel fractions after being separated in separation plants. According to this study, the biggest cities in Brazil generate about 18.9 million tonnes of municipal solid waste per year (2011), of which 51.5% is biogenic matter. The overall domestic consumption of electricity is 480,120 GWh y(-1) in Brazil and the municipal solid waste incineration in the 16 largest cities in the country could replace 1.8% of it using incinerators. The city of São Paulo could produce 637 GWh y(-1) with landfill gas, 2368 GWh y(-1) with incineration of municipal solid waste and 1177 GWh y(-1) with incineration of refuse-derived fuel. The latter two scenarios could replace 27% and 13.5% of the residential electrical energy consumption in the city. This shows that thermal treatment might be a viable option of waste-to-energy in Brazil., (© The Author(s) 2014.)

Fenoterol and salbutamol were determined by electrogenerated chemiluminescence (ECL) coupled with flow injection analysis (FIA), using Ru(bpy)(3)(2+) as the luminescent substance. Fenoterol and salbutamol oxidize together with the ruthenium 2,2-bipyridyl at a platinum electrode, which leads to an increase in the luminescent intensity, and this increase is proportional to the analyte concentration. For fenoterol a linear calibration curve within the range from 1.0x10(-5) to 1.0x10(-4)mol l(-1) was obtained with a correlation coefficient of 0.998 (n=5) and for salbutamol the linear analytical curve was also obtained in this range with a correlation coefficient of 0.995 (n=5). The relative standard deviation was estimated as < or =2.5% for 3x10(-5)mol l(-1) for fenoterol solution and as < or =1.3% for 5.0x10(-5)mol l(-1) salbutamol solution for 15 successive injections. The limit of detection for fenoterol was 2.4x10(-7)mol l(-1) and for salbutamol was 4.0x10(-7)mol l(-1). Fenoterol and salbutamol were successfully determined in drug tablets and the soluble components of the matrix did not interfere in the luminescent emission. The results obtained using the luminescent methodology were not statistically different from those obtained by UV-spectrophotometry at 95% confidence level.