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Chile, the world's leading copper producer, generates significant volumes of mining waters, some of which cannot be recirculated into the production process. These mining waters are characterized by elevated sulfate ( SO 4 2 − ) concentrations, requiring sustainable management strategies for potential reuse. This study aims to evaluate the rhizofiltration technique using Carpobrotus chilensis for treating mining waters with a high SO 4 2 − concentration. Initially, the mining waters exhibited a pH of 7.97 ± 0.16 and a SO 4 2 − concentration of 2,743 ± 137 mg L−1, while the control water had a pH of 7.88 ± 0.08 and a SO 4 2 − concentration of 775 ± 19.0 mg L−1. The plants were hydroponically cultivated in 40 L containers with mining waters and drinking water as a control. Over an 8-week period, the pH of the mining water decreased to 3.12 ± 0.01, and the SO 4 2 − concentration declined to 2,200 ± 110 mg L−1. Notably, the fresh weight of roots was significantly higher in plants grown in mining water (22.2 ± 6.66 g) compared to those in the control treatment (14.3 ± 4.28 g). However, an undesirable increase in the acidity was observed in the mining waters after rhizofiltration, which was attributed to hydrogen sulfate (HSO4-) and/or root exudates. Despite the unexpected increase in acidity, C. chilensis effectively reduced the concentration of SO 4 2 − in mining waters by 20%. Additionally, the C. chilensis roots accumulated 4.84 ± 1.40% of sulfur (S), a level comparable to thiophore plants. This study provides evidence that this non-aquatic plant can be used in sulfate rhizofiltration. Caprobrotus chilensis is a good candidate for sulfate rhizolfiltration in mining waters. The accumulation of sulfur by the roots of Carpobrotus chilensis reached 4.84% Mining waters with a high concentration of sulfates require control of the redox potential [ABSTRACT FROM AUTHOR]

The indoor airflow with a natural ventilation system was numerically calculated using the laminar and turbulent approach. In the chemical laboratory of the Technical University of Ambato, the computational code OpenFoam demonstrated an ability to numerically predict flow patterns. The design contemplated the natural ventilation system considering the laboratories’ working conditions not only in summer, but also in a winter week. These two operating conditions are calculated on a fully open and closed environment. For a room with a capacity of 20 people, the climate data average values were recorded at 14.0 ° C, 81.7%, 1.7 m /s for temperature, relative humidity, and wind speed, respectively. Furthermore, the demonstration has shown that the homogeneous occupancy air speed average is was 0.7 m / s with a facade air intake of 1.0 m / s 0.6 m / s in the room valid for the exchange of air and evacuation of pollutants. The maximum pressures were found in the lower part of the laboratory. This prevents the modification of the thermo-hygrometric conditions.

Critical fabrication process factors were examined using a Taguchi experimental matrix for their effect on high-temperature superconducting (HTS) edge junction fabrications. These factors include angle of HTS deposition by pulsed laser deposition (PLD), pre-cleaning and annealing dwell time prior to epitaxial depositions and angle of film edges created by ion milling. Experimental results show that of all three factors, the base electrode deposition technique significantly affects the junction critical current spread and performance.

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