The exponential growth of electronic waste pollution, including outdated electrical equipment, is a significant environmental and health concern. To protect the ecosystem from e-waste contamination, chemical engineering with its prominent processes such as leaching, pyrolysis, etc. can take a leading role in resource recovery, eco-friendly waste management, and sustainable e-waste recycling. This review presents a detailed analysis of e-waste recycling technologies from the chemical engineering perspective. Several smart solutions are discussed for managing and recovering important e-waste components, including semiconductor chips, metals (Pb, Al, Steel, Ni, Ag, Au, Pd), rare-earth minerals, etc. Various metals recovered by electro-winning from cell phones, and integrated circuits, can be used to produce corrosion-resistant appliances, IoT (Internet of Things) devices like sensors, and robotics related to chemical sciences. This paper concentrates on strategies for recovering materials that can be used to make chemical engineering equipment and IoT devices, along with the roadblocks and potential connected with these strategies. This study compares the various e-waste recycling procedures on photoelectronic trash from the last few years. The paper also focuses on green upcycling and effective e-trash management from discarded keyboards into value-added goods like musical tools and innovative artistic sculptures and also from seawater. This paper portrays the pyrometallurgical and valorization of digital rubbish such as printed circuit boards (PCBs), reactors, and transistors for e-waste-based nanorobots. This review also emphasizes the difficulty of managing the growing amounts of e-waste globally and the damaging effects on the environment and human health caused by improper disposal.
Sustainable and ecologically friendly discharge of slaughterhouse wastewater requires effective treatment. The chicken slaughter house wastewater (CHSW) samples exhibited elevated organic contents with the chemical oxygen demand (COD) (2,111.33 ± 31.63 mg L −1 ), total organic carbon (TOC) (717.64 ± 31.63 mg L −1 ), biological oxygen demand (BOD 5 ) (1,350 ± 24.49 mg L −1 ), ammonical-N (77.03 ± 0.24 mg L −1 ), phosphate (4.05 ± 0.02 mg L −1 ) and TSS (833 ± 12.72 mg L −1 ). The present research investigated the treatment of CHSW using biochar, derived from a market waste (waste corncob), employing H 3 PO 4 as the impregnating agent in the carbonization process. The removal of TOC, COD, phosphate, BOD 5 , and ammoniacal-N were found as 85 ± 5 %, 84.51 ± 2.32 %, 15.70 ± 0.23 %, 79.54 ± 2.27 %, and 74.03 ± 1.11 % respectively, when 40 mL CHSW was treated with 5 g L −1 biochar (size: 253 μm) for 120 min at its own pH. A 2-D transient convective-diffusive model based on a numerical method was employed and validated. A single-factor local sensitivity analysis was also conducted using the relative marginal value (RMV).
The Persistent Scatterers Interferometry (PSI) method enables displacement estimation with millimeter accuracy. However, the uncertain positioning of Point Scatterers (PS) makes it difficult to associate them with real objects in space and hampers the interpretation of the results. This article proposes a methodology to enhance the accuracy of PS positions. The methodology successfully establishes links between PS and real objects by associating them with the most likely candidate points extracted from Airborne Laser Scanning (ALS) point clouds. The selection process for suitable candidates is based on ALS analysis of return number, classification, and geometric features determined by neighborhood analysis. The linking process involves determining global transformation parameters for PSs using the Iterative Closest Point (ICP) algorithm. Then, the nearest neighbor search within the error ellipsoid of the PS positions is performed. Tests conducted demonstrated that this method allows for linking more than 80 % and 65 % of the PS derived from Sentinel-1 and TerraSAR-X mission data, respectively, in both ascending and descending geometries. To validate the obtained results, in addition to the quantitative assessment, a qualitative analysis is performed based on a developed 3D visualization module showing all stages of the proposed methodology.
Reichenbach’s common cause principle (RCCP) is a metaphysical claim about the causal structure of the world. It entails that all correlations can be explained causally either by pointing at the causal connection between the correlated entities or by displaying a common cause of the correlation. We contribute to its mathematical side.
This systematic review explores how Islamic principles interpret and support children’s participation in decision-making processes across various contexts. Although Islamic teachings particularly through values such as shūrā (mutual consultation), ʿadl (justice), tarbiyah (nurturing), ʿaql (intellect), and maṣlaḥah (public interest) strongly advocate for children’s involvement, practical application remains limited. A systematic search was conducted following PRISMA guidelines across major databases, resulting in the inclusion of 19 relevant studies. Findings highlight a growing recognition of children’s evolving autonomy in Islamic scholarship but also reveal significant barriers, including cultural misconceptions, adult-centered authority, lack of awareness, and limited resources. Facilitators such as trust-building, age-appropriate information, and supportive environments were identified as critical to empowering children’s participation. Interventions grounded in Islamic values are recommended to bridge the gap between principle and practice. This review underscores the need for policies, training, and research that center children’s voices while aligning with Islamic ethical frameworks, ultimately fostering a more inclusive and just approach to child decision-making in Muslim communities.
Due to the urgent need for sustainable energy around the world, piezoelectric energy harvesting (PEH) has become very popular due to its capability to harvest electrical energy from ambient mechanical energy. From numerous possible configurations, cantilever-based beams have become very popular among researchers due to their adaptability and structural simplicity. Recently, rotational piezoelectric energy harvesters have gained prominence due to their ability in continuous energy capture from sources such as wind, human motion, and rotating machinery. The aim is to provide more clarity on the underlying concept of energy harvesting models by carefully compiling comprehensive information. In summary, this research performs a comprehensive review on the latest progress in research on rotating and non-rotating PEHs, considering their research background, excitation principles, harvester modes, etc. After a comprehensive investigation, it was found that structures using rotational motions outperformed available energy harvesting designs in such systems.