This experimental study focused on rock weathering to understand the geochemical processes involved in the host rock matrix and the water at different time intervals. In this study, five different tanks were designed in the laboratory, consisting of montmorillonite clay (T1), coarse peridotite and clay (T2), finer peridotite and clay (T3), peridotite (T4) and only lake water as a control (T5). The T1-T4 tanks were allowed to react with natural lake water in a laboratory setup for eight weeks. During the experiment, weekly measurements were taken for physical parameters, major ions, and trace metals in water. The results show that increasing pH and HCO3- initiates the rock weathering by acquiring CO2 directly from the air at the early stage of the experiment. Subsequently, precipitation of carbonate minerals, resulting from the removal of Ca2+ and Mg2+ from the liquid in the later stages of the experiment. Principal component analysis also confirms the early dissolution of minerals as a carbon source, followed by enhanced weathering leads to the precipitation of carbonate minerals. Based on solid chemistry, experiments with clay (T1) and peridotite (T4) enhance mineral precipitation, whereas a mixture of rocks (T2 and T3) supports mineral dissolution. T1 exhibits a high adsorption capacity for Fe and Ni, attributed to both ion exchange and surface complexation. In these experiments, carbonates would nucleate preferentially on or within clay-rich aggregates, where Ca2+, Mg2+ and HCO3- are concentrated at the grain-water interface via cation exchange and surface complexation, thereby enhancing early crystal growth.
Monitoring microplastics (MPs) has become a global priority requiring equitable analytical capacity, particularly in the Global South. Through the NUTEC Plastics initiative, the IAEA has addressed this need by developing a harmonized protocol and providing training and equipment to its Member States. The initial phase targeted large MPs (0.3-5 mm) in beach sand. To assess data comparability and analytical performance, a proficiency test was organized in which 49 laboratories from 41 countries analyzed a blind beach-sand sample spiked with a defined number and composition of MPs, reporting counts and polymer identity by size fraction. Recovery was strongly size-dependent. Performance was reliable for the large fraction (1-5 mm), where 22 laboratories (similar to 45%) recovered the exact spiked count, in contrast to one laboratory (similar to 2%) for the small fraction (0.3-1 mm). Of the 41 laboratories identifying polymers, 18 (similar to 44%) failed to detect any transparent polystyrene particles. Generalized linear modelling identified the agitation method during density separation as the only significant predictor of polystyrene recovery, with mechanical shaking yielding similar to 1.77-fold higher recovery than magnetic stirring. Approximately one in four reported particles could not be attributed to spiked polymers. These findings identify targets and define priorities for the next capacity-building phase: improving recovery of small and transparent particles, and further standardizing agitation, contamination control, and data reporting. Altogether, this study provides a framework for method refinement and a step toward standardized global MP monitoring.
Understanding long-term microbial dynamics in semi-enclosed coastal systems is essential for evaluating wastewater-related impacts and informing management responses. This study applies an integrated nonparametric diagnostic framework to characterize seven years (2010–2016) of total coliform (TC) variability at two shoreline stations in Kuwait. Annual mean TC concentrations were analyzed using Mann–Kendall trend tests, Sen’s slope estimation, Pettitt change-point detection, percentile-based anomaly classification, and first-order decay modeling. Station S07 exhibited exceptionally high TC levels during 2010–2011, followed by a statistically significant change point and lower annual concentrations from 2012 onward. Trend diagnostics confirmed a significant downward trajectory, and decay modeling indicated rapid attenuation (λ = 0.327 year⁻1; half-life = 2.12 years). In contrast, station S09 remained consistently lower in magnitude, showed no clear structural shift, and displayed a slower but measurable long-term decline (λ = 0.188 year⁻1; half-life = 3.69 years). The analyses indicate contrasting annual contamination patterns between the two stations, with S07 reflecting a more dynamic, contamination-prone setting and S09 a comparatively stable, lower-intensity setting. Interpreted within the limits of annual summary data and restricted environmental covariate information, these findings provide a cautious basis for evaluating broad microbial contrasts in data-limited coastal systems and can guide future studies using higher-resolution observations.
Solar desalination has become a viable way to address the world's water shortage using renewable energy. This review comprehensively analyzes solar desalination systems to examine the several modified designs that can improve their efficiency. Incorporation of reflectors, wick materials, different types of fins, absorbers, solar collectors, and heat localization materials into the solar desalination system has been studied in detail. The incorporation of solar collectors with a desalination system provides the dual advantage, i.e., enhancing the water productivity and simultaneously producing the hot water which can be utilized for different household chores. A comparison of the efficiencies for different developed solar desalination systems with and without reflectors was also carried out. The use of nano-materials/biomaterials to enhance the performance of solar desalination systems and their impact on improving evaporation rates and overall system efficiency was also reviewed. To achieve the sustainable development goals through solar desalination, and comprehensive search for the bibliometric analysis has been carried out through the Scopus database. Furthermore, solar desalination potential for wastewater treatment is discussed, highlighting its feasibility for industrial and domestic applications. The review also explores the integration of artificial intelligence in optimizing system performance, predictive modelling, and process automation. This study provides a comprehensive evaluation of solar desalination systems, offering insights into scalable, cost-effective solutions and future direction for the sustainable management of water resources.
Nanoporous carbon materials were synthesized from asphaltenes using a thermo-chemical treatment under an inert atmosphere and in-situ KOH activation. N-doping was also employed in certain samples to reveal the impact of nitrogen on the properties of materials. The synthesized materials were fully characterized to disclose their textural properties, structural parameters, surface functional groups, elemental compositions, and morphologies. Textural property analysis revealed a remarkable increase in surface areas after alkaline treatment (similar to 1500-2000 m(2)/g), which was mainly ascribed to the formation of micro- and mesopores. The measurements of structural parameters endorse and complement the findings on textural properties. The asphaltene-derived porous carbons have been employed in energy storage and carbon capture applications. The materials exhibit specific capacitances ranging from 130 to 180 F/g at 0.2 A/g in a 3 M KOH. These results suggest that nitrogen doping significantly enhances the pseudocapacitive behavior of the electroactive materials by promoting Faradaic redox reactions and improving ion diffusion and adsorption rates. Asphaltene-derived porous carbons also exhibit notable CO2 adsorption capacities of 3-4 mmol/g at 25 degrees C and 1 bar. Also, breakthrough experiments confirm that the N-doped material exhibits remarkable stability, reusability, and increased surface basicity, achieving an impressive CO2 uptake of 0.446 mmol/g. These results highlight the potential of asphaltene-based porous carbons as efficient materials for carbon capture and energy storage applications.
