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Apr 16, 2021

Thermodynamic study on lead leaching from sodium citrate

Lead-acid batteries account for 60% of the world’s electrical energy storage batteries. About 50% of global lead consumption comes from recycled and reused materials. Currently, pyrometallurgical methods account for more than 90% of lead recovery technology; however, these processes are criticized due to sulfur dioxide emissions from the decomposition of lead sulfate at elevated temperatures, in addition to particulate emissions. Lead recovery by recycling batteries by

hydrometallurgical processes has been investigated as an alternative to pyrometallurgical processes. In the present work, a thermodynamic analysis of lead leaching with sodium citrate was performed. The thermodynamic analysis was based on the study of three stability diagrams constructed with Medusa^® software. Leaching tests were carried out to get to know the system, corroborate the thermodynamic analysis performed, and study the behavior of the system. The results obtained show that it is possible to extract 100% lead with a leaching agent concentration of 0.25 M, a 1:1 solid-liquid

ratio, and 25 ℃.

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May 18, 2021

India’s demographic dividend or disaster? Mismanaged factors of production—Land, labor, infrastructure, cities

India entered its so-called demographic dividend around 2005—expected to last until 2055. India has already utilized almost a third of the period of its demographic dividend—it saw a period of explosive growth from 2003–2012—but has not been able to sustain that growth. And since 2012, growth has generated less and less employment, as it has turned inward, and so it is not helping the working-age population get usefully employed. The labor force participation rate for women has been low and is now falling. What can be done to use India’s underlying factors of production better to generate greater, more inclusive, and sustained prosperity for its citizens? These second-generation reforms are not easy, as they need cooperative federalism and much broader consensus, but without them India’s demographic dividend may become a disaster.

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Oct 12, 2022

Advances in atom transfer radical polymerization of modified grain

Atom transfer radical polymerization (ATRP) is a kind of controllable reactive radical polymerization method with potential application value. The modification of graphene oxide (GO) by ATRP reaction can eﬀectively control various graft polymer molecules Chain length and graft density, giving GO diﬀerent functionality, such as good solvent dispersibility, environmental sensitive stimulus responsiveness, biocompatibility, and the like. In this paper, ATRP reaction and GO surface non-covalent bonding ATRP polymer molecular chain were directly initiated from GO surface immobilization initiator. The ATRP reaction modified GO was reviewed, and the process conditions and research methods of ATRP modification reaction were summarized, as well as pointed out the functional characteristics and application prospect of GO functionalized composites.

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Apr 29, 2025

Stability mechanism and ultrasonic destabilization mechanism of polymer waste drilling fluid

Polymer waste drilling fluid has extremely high stability, and it is difficult to separate solid from liquid, which has become a key bottleneck problem restricting its resource recycling. This study aims to reveal the stability mechanism of polymer waste drilling fluid and explore the destabilization effect and mechanism of ultrasonic waste drilling fluid. Surface analysis techniques such as X-ray energy spectrum and infrared spectrum were used in combination with colloidal chemical methods to study the spatial molecular structure, stability mechanism, and ultrasonic destabilization mechanism of drilling fluid. The results show that the particles in the drilling fluid exist in two forms: uncoated particles and particles coated by polymers, forming a high molecular stable particle system. Among them, rock particles not coated by polymer follow the vacancy stability and Derjaguin-Landau-Verwey-Overbeek (DLVO) stability mechanism, and the weighting material coated by the polymer surface follows the space stability and DLVO stability mechanism. The results of ultrasonic destabilization experiments show that after ultrasonic treatment at 1000 W power for 5 min, coupled with the addition of 0.02% cationic polyacrylamide, the dehydration rate is as high as 81.0%, and the moisture content of the mud cake is as low as 29.3%, achieving an excellent solid-liquid separation effect. Ultrasound destabilizes polymer waste drilling fluid by destroying the long-chain structure of the polymer. This study provides theoretical support and research direction for the research and development of polymer waste drilling fluid destabilization technology.

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Jan 8, 2025

Application of the SWAT model for water budgeting and water resource planning in Oued Cherraa basin (northeastern Morocco)

This study focuses on the use of the Soil and Water Assessment Tool (SWAT) model for water budgeting and resource planning in Oued Cherraa basin. The combination of hydrological models such as SWAT with reliable meteorological data makes it possible to simulate water availability and manage water resources. In this study, the SWAT model was employed to estimate hydrological parameters in the Oued Cherra basin, utilizing meteorological data (2012–2020) sourced from the Moulouya Hydraulic Basin Agency (ABHM). The hydrology of the basin is therefore represented by point data from the Tazarhine hydrological station for the 2009–2020 period. In order to optimize the accuracy of a specific model, namely SWAT-CUP, a calibration and validation process was carried out on the aforementioned model using observed flow data. The SUFI-2 algorithm was utilized in this process, with the aim of enhancing its precision. The performance of the model was then evaluated using statistical parameters, with particular attention being given to Nash-Sutcliffe efficiency (NSE) and coefficient of determination (R²). The NSE values for the study were 0.58 for calibration and 0.60 for validation, while the corresponding R² values were 0.66 and 0.63. The study examined 16 hydrological parameters for Oued Cherra, determining that evapotranspiration accounted for 89% of the annual rainfall, while surface runoff constituted only 6%. It also showed that groundwater recharge was pretty much negligible. This emphasized how important it is to manage water resources effectively. The calibrated SWAT model replicated flow patterns pretty well, which gave us some valuable insights into the water balance and availability. The study’s primary conclusions were that surface water is limited and that shallow aquifers are a really important source of water storage, especially for irrigation during droughts.

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Nov 7, 2024

Exploring Higher Education Curriculum Reform under the Wave of Artificial Intelligence

Artificial intelligence has triggered a global wave of the times with its breakthrough intelligent technology features such as autonomous learning ability, self-attention, and reasoning ability, which has also led to a huge change in the demand for talents in the society, and various industries are inclined to the composite innovative and high-quality talents with cross-field and multi-disciplinary backgrounds, so that the reform of higher education curriculum empowered by artificial intelligence has become an inevitable trend. It is found that although many colleges and universities have gradually opened general education and professional education on artificial intelligence, the reform of higher education curriculum still faces various problems such as monotonous teaching mode, lagging teaching content, academic ethics and morality. In order to effectively deal with these problems, this paper provides corresponding suggestions from the perspective of expecting the joint efforts and close collaboration between universities and enterprises.

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