The stationary version of the Boussinesq system with a general gravitational acceleration term is considered. Under suitable assumptions on this term, as well as on the external forces acting on each equation of this coupled system, we first establish the existence of weak solutions in the natural energy space H˙1(R3). The uniqueness of these solutions is a challenging open problem. Within this framework, our first main contribution is to show that any weak H˙1-solution exhibits an analytic smoothing effect in the Gevrey class. Our second main contribution is to show that the Gevrey class regularity can also be used to study the uniqueness problem, provided that these solutions satisfy a suitable low-frequency control. As a by-product, we also obtain new regularity results and a new Liouville-type result for weak H˙1-solutions of the classical Navier–Stokes equations.
This paper analyses the water flow in curved channels, which may present particular hydrodynamic patterns such as streamline alteration, cross-wave formation, recirculation zones and possible contour flow separations, all of which require detailed hydrodynamic analysis. The analysis focuses on a case study of a hydroelectric power plant intake with a side grate, which includes a curved (small-radius) gravel-removing channel connecting the intake works to two desanding chambers. This design results in an unequal distribution of flow to the desanding chambers, causing neither chamber to function properly, and a recirculation zone upstream of the left desanding chamber. The methodology uses three-dimensional numerical modelling in OpenFOAM, based on prototype data. The model was calibrated with a flow rate of 8,8 m3/s. Subsequently, the transit of the design flow of 13 m3/s was simulated and an uneven flow distribution in the desanding chambers was verified. To address this problem, and considering the higher-velocity streamlines, two groups of alternatives were considered: the first consisted of placing two panels of different special shapes (straight, broken, and curved) in the desilting chamber; the second examined the flow behavior with an increased number of panels and alteration aspect ratio. For the first group, the scenarios tested did not modify the flow distribution in the sand removal chambers; however, the panels locally changed the hydrodynamic conditions and successfully altered the recirculation zone location. The scenarios in the second group yielded the best operational results regarding flow distribution.
Contamination of water bodies caused by increasing human and industrial activities poses a serious threat to human health and environmental sustainability, highlighting the need for green and efficient remediation strategies. In this study, a facile hydrothermal synthesis followed by controlled calcination was developed to fabricate phase-pure α- and β-Bi2O3 with a unique coral-like hierarchical morphology as visible-light-active photocatalysts. Phase selectivity was achieved by tuning the calcination temperature, yielding pure β-Bi2O3 while preserving the hierarchical structure. Optical characterization revealed a narrower bandgap for β-Bi2O3 (2.24 eV) compared to α-Bi2O3 (2.75 eV), favoring visible-light absorption. Photocatalytic performance was evaluated using Rhodamine B as a model pollutant, where β-Bi2O3 achieved complete degradation within 240 min, significantly outperforming α-Bi2O3. The degradation followed pseudo-first-order kinetics, and the catalyst exhibited excellent robustness and reusability. To further demonstrate applicability toward persistent contaminants, Methyl Orange (MO) and the antibiotic ciprofloxacin (CIP) were employed as additional model pollutants. The coral-like β-Bi2O3 showed high visible-light activity toward MO, including complete removal under acidic conditions. Moreover, efficient degradation of CIP was achieved at neutral pH, with 90% removal within 150 min and complete degradation after 240 min. Overall, these results highlight coral-like β-Bi2O3 as an efficient standalone photocatalyst for visible-light-driven degradation of dye and pharmaceutical pollutants.
This work consists of a systematised review examining recent models for agri-food supply chain management (AFSCM), focusing on artificial intelligence (AI) applications and sustainability integration. Through PRISMA methodology, we conducted a descriptive statistical analysis of 183 articles published between 2019 and 2023. The dimensional analysis revealed that strategic modelling represented 55% of approaches, while perishable products were considered in 58% of studies. Sustainability principles were integrated into 74% of the models, while AI applications showed a limited 14% adoption across AFSCM. The analysis of AI implementations showed distribution in agricultural production management at 27%, transportation and logistics at 8%, and sustainability planning at 19%. A novel AFSCM taxonomy was developed through systematic classification, combining quantitative bibliometric analysis, qualitative thematic analysis and expert interpretation. The results identified gaps in mixed methods approaches and tactical or operational modelling, providing a structured framework for future research directions in AI integration and sustainable practices across agri-food supply chains.
The global demand for metals has experienced a critical increase in recent decades, and this trend is anticipated to persist in the coming years. Notably, the electric and electronic devices (EEE) sector and the electric vehicle industry are emerging as significant contributors to this heightened demand. Within these domains, the key player in terms of metal consumption is the battery, with Lithium-ion (Li-ion) batteries being the predominant choice due to their efficiency. Several methods have been investigated to recover metals from Li-ion batteries, focusing on the recovery without assessing the impacts generated. To address this gap, an experimental analysis focused on the recovery of crucial metals found in smartphones and laptop batteries, including lithium (Li), cobalt (Co), and manganese (Mn) was conducted. Then, the life cycle assessment was undertaken to calculate the environmental impacts of the hydrometallurgical route by using sulfuric acid and to analyze the ecological footprint associated with the recycling process. The acquired experimental data served as a basis for simulating the recycling process using specialized software, HSC Chemistry. This simulation facilitated the process's scaling up and enabled optimization and precise calculation of reagents and water usage during recycling. Thus, this study not only explores the difficulties of recycling processes but also the impacts associated with them, offering valuable insights into the ongoing discussions around responsible and sustainable practices in response to the growing global demand for metals.
