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The treatment of textile wastewater (TWW) loaded with recalcitrant azo dyes in bioelectrochemical systems (BES) rather than in physicochemical processes is a low-cost and environmentally friendly process. The main objective of this study is to investigate the potential of different saline sediments collected from extreme Tunisian environments for the formation of bioanodes capable ofsimultaneous azo dyes degradation and electric current generation in synthetic (STWW) and real textile wastewaters (RTWW) characterized by a varied composition of azo dyes and a high salinity. The obtained bioanodes and anolytes were studied comparatively by electrochemical, microscopic, analytical, and molecular tools.Based on the UV–visible spectra analysis, the breakdown of the azo bond was confirmed. With RTWW, the BES achieved a chemical oxygen demand (COD) abatement rate of 85%with a current density of 2.5 A/m2. Microbial community analysis indicated that a diverse community of bacteria was active for effluent treatment coupled with energy production. At the phylum level, the electrodes were primarily colonized by proteobacteria and firmicutes, which are the two phyla most involved in bioremediation. The analysis of the microbial community also showed the abundance of Marinobacter hydrocarbonoclasticus and Marinobacter sp. species characterized by their high metabolic capacity, tolerance to extremophilic conditions, and role in hydrocarbon degradation. [ABSTRACT FROM AUTHOR]

The detection and quantification of Indole -3 Acetic Acid (IAA) produced by Plant growth promoting rhizobacteria (PGPR) rely on a standard well-documented assay, which remains time-consuming, laborious, and costly. These drawbacks led to sway interest to economic and reliable assays. The aim of this work is to validate and standardize a fast, reliable, and cost-effective microassay to quantify IAA produced by bacteria with an easy microplate method. In order to validate the accuracy of the IAA microplate assay, bacterial samples from different genera were assayed using two methods: the conventional IAA estimation assay and the IAA micro- assay. The microassay shows a prominent reduction in used bacterial supernatant volume as well as Salkowski reagent volume of about 92.5%. It is considerably cheaper than the conventional one of around 56%. The newly performed microplate assay is 23 times faster. The result of IAA quantitative analysis for 13 bacterial strains showed that Bacillus muralis and Bacillus toyonensis produced the highest IAA concentration (23.64±0.003μg/ml and 23.35±0.006μg/ml, respectively). The obtained data from both methods were highly correlated with an R-value of 0.979. The microassay offers the ability to read the optical density of all samples simultaneously since used volumes of bacterial supernatants and Salkowski reagent were minimized to place the mixture in 96-well microplates, which reduces greatly required labor. Furthermore, the application of the IAA micro-plate assay reduces drastically the reagent waste and toxicity hazard of Salkowski reagent in the environment, thus, we can classify it as eco-friendly respecting the Green Chemistry concept according to Environmental Protection Agency (EPA). The IAA microassay is a, reliable, rapid and cost-effective and eco-friendly method to screen plant growth promoting potential of more than 23 bacterial strains by microplate. It could be an alternative for the conventional IAA assay as a routine research tool. [ABSTRACT FROM AUTHOR]

The paper presents a comparative study of the steady-state and transient behaviors of three-level neutral-point clamped (3L-NPC) inverter-fed induction motor (IM) drives under the control of three predictive torque control (PTC) schemes: the conventional one (C-PTC) and two new strategies involving selected stator voltage vectors (SVs), namely: (SV-PTC1) and (SV-PTC2). Compared to the C-PTC, the latter enable a reduction of the number of voltage vectors as well as the weighting factors. The introduced PTCs mainly differ by the cost function, which is more simple in the case of SV-PTC2. However, SV-PTC1 allows a systematic clamping of each stator phase to the DC bus voltage, at a low level of 60 degrees, and a high level at 60 degrees per cycle, while such a clamping is arbitrary in the case of SV-PTC2. Simulations prove the higher performances of the introduced SV-PTCs over the C-PTC ones, in terms of the reduction of the current distortion and of the torque ripple. Simulation results were validated by the experiments. [ABSTRACT FROM AUTHOR]

We present a new integrated electromechanical set for automotive hybrid propulsion systems. It consists of two concentric permanent-magnet (PM) machines with inner and outer surface-mounted PM rotors, and a stator sandwiched between the two rotors, yielding a so-called 'single-stator dual-rotor PM machine.' The stator magnetic circuit consists of two concentric parts decoupled by a nonmagnetic ring. In an earlier topology, distributed windings were used in both stators. We substitute concentrated windings to extend the flux weakening range. We discuss our investigation of the magnetomotive force (MMF) spatial profile and of the torque production capability of this dedicated concentrated winding surface-mounted PM machine. Index Terms--Concentrated winding, magnetomotive force, single-stator dual-rotor permanent-magnet machine, torque production capability, total harmonic distortion.