A new strategy has been developed to investigate a low-cost porous carbon electrode material derived from bio-waste rotten roselle, activated with potassium carbonate (K2CO3) under a nitrogen atmosphere via a direct activation method, without pre-carbonization. This activated carbon, referred to as Rotten Roselle Activated Carbon (RRAC), is intended for supercapacitor applications due to its anticipated high surface area, porous architecture, and favorable electrochemical properties. RRAC was characterized using powder X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), Raman spectroscopy, field emission scanning electron microscopy (FESEM), Brunauer–Emmett–Teller (BET) analysis, and X-ray photoelectron spectroscopy (XPS). The activated carbon composite exhibited a high specific surface area of 2225 m2 g− 1 and a substantial presence of micropores, which facilitate efficient ion and electron transport, thereby enhancing electrochemical performance. A maximum specific capacitance of 262 F g− 1 at 0.5 A g− 1 was obtained from the galvanostatic charge–discharge curve. Moreover, the RRAC material retained 89

Batch reactors are primarily used to produce high-value-added chemicals and active pharmaceutical ingredients. A combination of parametric design and 3D printing has enabled the manufacture of innovative geometries for bespoke continuous-flow reactors. In this study, continuous flow reactors with novel polygonal channels were created using a 2D Hilbert space-filling curves. These shapes allow a different surface area to volume ratio and the possibility to twist them over their axis improving mixing. The effect of channel rotation on secondary mixing was investigated for triangular and quadrangular channels. As these reactors exhibited multiple curves, the effect of 3D printing on their produced volume and topology was also analyzed. There is a systematic reduction of the targeted volume of the designed reactors that can be up to 13% choosing a supportless orientation. The performance of manufactured reactors was assessed using step-input residence time distribution (RTD) measurements and by comparing the corresponding results with computational fluid dynamics simulations.

Low-calorie sweeteners (LCS), also known as non-nutritive or artificial sweeteners, are widely used as sugar substitutes because they provide intense sweetness with little or no caloric value. Their consumption has increased substantially in response to the global rise in obesity, type 2 diabetes, and other metabolic disorders, reflecting efforts to reduce added sugar intake while maintaining palatability. Despite widespread use, questions remain regarding their long-term metabolic, physiological, and microbiological effects. To provide a comprehensive and evidence-based review of the current scientific literature on the health effects of LCS, focusing on their impact on body weight, glycemic control, appetite regulation, gut microbiota, dental health, and behavioral outcomes, while distinguishing established evidence from areas requiring further investigation. This review critically evaluated findings from randomized controlled trials, systematic reviews, meta-analyses, and selected observational studies examining commonly used LCS, including aspartame, sucralose, saccharin, acesulfame potassium, and steviol glycosides. Evidence was synthesized to assess physiological, metabolic, microbiological, and behavioral outcomes, with emphasis on the quality and consistency of available data. Current evidence indicates that replacing sugar with LCS in energy-restricted diets can support modest weight management and improve glycemic control without significantly affecting insulin secretion or postprandial blood glucose levels. LCS also contribute to reduced risk of dental caries by replacing fermentable sugars. High-quality clinical trials do not demonstrate consistent increases in appetite, energy intake, body weight, or sweet taste preference attributable to LCS consumption. However, emerging evidence suggests that LCS may influence gut microbiota composition and metabolic signaling in a subset of individuals, although findings remain inconsistent across different sweeteners, study populations, and experimental designs. The available evidence supports the use of approved LCS as safe and effective alternatives to sugar when consumed within established acceptable daily intake levels. Their benefits in reducing sugar intake, supporting weight management, improving glycemic control, and promoting oral health are supported by substantial clinical evidence. Nevertheless, uncertainties remain regarding long-term effects on gut microbiota, metabolic regulation, and interindividual variability. Future well-designed longitudinal studies integrating multi-omics approaches and personalized nutrition are needed to clarify these mechanisms and optimize recommendations for LCS use in public health nutrition.

Traditional packed-bed adsorption columns suffer from poor thermal management due to low effective thermal conductivity, which leads to a reduced efficiency during cyclic operation. Gyroid structures provide a promising alternative to boost efficiency, providing key advantages such as lower pressure drop and enhanced heat transfer. These benefits stem from the high surface area of the gyroid framework and the improved connectivity of the gas flow pathways, which facilitate efficient mass and heat transfer. The novelty of this study is to investigate the efficiency of a composite structure of a highly conductive metallic gyroid framework with a thin adsorbent coating to significantly enhance heat transfer in adsorption columns. We present a three-dimensional (3D) computational fluid dynamics (CFD) analysis of gyroid-based adsorption columns, where an inert matrix with a gyroid shape is coated with KAUST-7 adsorbent for CO2 capture from flue gases. By employing a thermally conducting metal, such as stainless steel, for the internal matrix of the gyroid structure, heat transfer within the TPSA process is enhanced by several orders of magnitude. The 3D gyroid model is translated to a one-dimensional (1D) model to reduce computational effort and study the TPSA performance. Compared to a conventional packed adsorption column operated under identical conditions, the optimized gyroid configuration achieves approximately 100% increase in productivity and about 27% improvement in CO2 recovery, while maintaining high product purity greater than 99%. These results demonstrate the potential of adsorption columns with gyroid packings a plausible solution for next-generation carbon capture technologies.

This study focuses on developing cost-effective and eco-friendly counter electrodes for dye-sensitized solar cells (DSSCs) using Ziziphus mauritiana (ZM) leaf biomass as a sustainable alternative to platinum. Carbonaceous materials, designated as ZLP-650 and ZLP-750, were synthesized via a simple carbonization process at 650 and 750 °C. The novelty lies in converting abundant agricultural waste into high-performance carbon electrodes through a green, scalable approach, reducing reliance on platinum while supporting sustainable DSSC development. Analytical techniques like FTIR, Raman, TGA, XRD and XPS indicated that higher carbonization temperatures improved the material’s order, purity, and stability. Morphological evaluations, including SEM and BET, confirmed that both samples had a porous architecture critical for effective electrolyte penetration and catalytic function. The ZLP-750-based DSSC attained an elevated JSC of 12.66 mA/cm2, surpassing the 10.38 mA/cm2 observed for ZLP-650. ZLP-750 demonstrated an impressive current density (JSC) of 12.66 mA/cm2, and a commendable Power Conversion Efficiency (PCE) of 6.04 ± 0.02

The demand for high-end performance coupled with the continuous miniaturization of electrical and electronic devices has resulted in a significant increase in heat flux generation. Metal matrix composites (MMCs) are frequently used as heat spreader materials in electronic devices due to their enhanced thermal conductivity, mechanical properties, and other key characteristics, addressing the challenges posed by increasing power density in electronic and thermal systems. This study focuses on testing copper silicon carbide (CuSiC), a metal matrix composite, as a heat spreader placed between a heat source and a heat sink. Copper, which is used in microcontrollers and microchips, serves as the heat source. To facilitate more efficient heat removal and transmission from traditional high-power-density chips, a thermal management technique involving thermal interface material (TIM) has been applied, using graphene-based paste as the TIM between the specimens. The thermal conductivity of CuSiC has been experimentally estimated with temperature using the ASTM D5470 method. Subsequently, the heat transfer between the copper and CuSiC contact has been evaluated experimentally in terms of Thermal Contact Conductance (TCC), an important performance parameter. Axial heat flow experiments were conducted using a simple and reliable experimental setup based on the steady-state methodology. Initially, experiments were performed on bare specimen contacts across a range of input heat flux (21–69 kW/m2) and contact pressure (0.1–0.4 MPa). The experiments were then repeated under similar conditions with graphene paste as the TIM between the specimens. The results indicate improved TCC with graphene paste compared to bare contacts. The findings of this study are applicable to thermal management applications in electronic devices.

Salt Gradient Solar Ponds (SGSPs) offer a promising solution for sustainable thermal energy storage. This study introduces a novel trapezoidal SGSP enhanced with coal cinder as a porous medium and a double-glass cover to reduce convective heat loss and improve thermal retention. The research bridges a gap in existing literature by experimentally and numerically evaluating the impact of porous media on SGSP performance. Two configurations-a conventional pond (SGTSP-C) and a coal-cinder-enhanced version (SGTSP-CC)-were analyzed. The enhanced pond achieved a 26.63 % higher LCZ temperature, reaching 62.45 degrees C, compared to 49.32 degrees C in the baseline setup. Energy and exergy efficiencies improved notably from 9.2 % to 15.4 % and from 0.5 % to 0.94 %, respectively. Validated numerical simulations further confirmed that coal cinder enhances thermal stratification and stability by reducing convective mixing. The findings demonstrate the potential of porous media integration for improving SGSP efficiency and advancing solar thermal energy storage systems.

Despite the inherent advantages of fine powders due to their high surface area, their fluidization remains challenging due to strong interparticle forces, which promote structural non-homogeneities, leading to gas bypassing and unpredictable hydrodynamics. This study investigates the hydrodynamics of a pulsed fluidized bed using square-wave flow modulation to improve the fluidization of cohesive activated carbon powder, widely used in environmental applications. Four pulsation frequencies (0.025, 0.050, 0.10, and 0.25 Hz) were evaluated at amplitudes (N_Re/N_Remf) ranging from 2 to 10. The onset of non-homogeneities was consistently characterized by a negative gradient in the normalized pressure-drop-time profile. Low-frequency pulsation at 0.025 Hz failed to prevent structural failure even at a low amplitude of 2, as prolonged flow interruption allowed heterogeneities to consolidate. At 0.050 Hz, bed stability improved, with the onset of non-homogeneities emerging at a pulsation amplitude of 4. At 0.10 Hz, stable operation was maintained at intermediate amplitudes, with structural destabilization initiating near the distributor and propagating upward as amplitude increased. In contrast, increasing the frequency to 0.25 Hz markedly enhanced hydrodynamic stability by delaying the onset of non-homogeneities to substantially higher amplitudes. Frequency-domain analysis revealed that structurally stable cohesive beds strongly attenuate the imposed pulsation. The emergence of a distinct spectral peak at the fundamental frequency serves as a non-intrusive diagnostic marker of structural breakdown. These findings demonstrate that higher-frequency pulsation effectively mitigates the formation of non-homogeneities, and enhance the operation stability of fluidized bed of cohesive powders.

Desiccant-based air-conditioning systems have emerged as a promising alternative to conventional vapor-compression cooling, particularly for managing latent loads in hot–humid climates. This comprehensive review synthesizes more than a hundred experimental, numerical and techno-economic studies on solid, liquid and composite desiccant systems, with particular emphasis on desiccant material selection, regeneration methods and cooling technologies. Solid desiccants, especially silica gel remains the dominant material due to its low cost and ability to regenerate at moderate temperatures requirements (50–90°C) compatible with solar and low-grade waste heat, whereas zeolites, molecular sieves and advanced composites extend applicability to low-humidity or high-temperature environments but demand further durability and high-temperature regeneration assessment. Liquid desiccants such as LiCl and CaCl₂ demonstrate high moisture-absorption capacity and stable operation within 40–90°C, though long-term corrosion and carryover remain key constraints. composite desiccants, which synergistically combine solid matrices with hygroscopic salts, demonstrate notable performance gains, reporting 68–270% increases in equilibrium uptake and reduced regeneration energy demand. Across all system categories, a clear trend toward solar-thermal, heat-pump and waste-heat-driven regeneration is observed, achieving competitive thermal COP values relative to electric heating. Hybrid configurations integrating desiccant units with indirect or direct evaporative cooling, Maisotsenko-cycle devices, and vapour-compression subsystems consistently enhance COP and reduce electrical consumption by 20–50%. The review concludes that climate-specific material selection, regeneration-temperature matching, and composite-coated heat exchangers are central to advancing next-generation, low-carbon desiccant cooling technologies.

Fine powders, despite their advantageous high surface area characteristics, often exhibit poor fluidization behavior due to their inherent cohesiveness. This cohesiveness leads to the evolution of structural irregularities, such as cracks and channels, resulting in unpredictable fluidization behavior and poor gas-solid interphase mixing. This study explores the potential of square-wave pulsed flow to enhance the fluidization of highly cohesive activated carbon powder, which is widely used due to its exceptional adsorptive properties. The effect of pulsation frequencies ranging from 0.025 to 0.25 Hz on fluidization hydrodynamics was assessed by analyzing pressure drop transients across the bed. Our results reveal that pulsed flow effectively delays the onset of structural nonhomogeneities, extending the stable operating range by up to four times compared to that of conventional, unassisted fluidization. High-frequency pulsations showed superior efficacy, highlighting the potential of pulsed flow for improving the fluidization behavior of cohesive powders.

The coalbed gas content, gas composition and stable isotope geochemistry of coalbed gas were investigated to study the generation mechanism of coalbed gas. The dry gas content of coalbed gas samples ranges from 2 to 10 m(3)/t. The composition of coalbed gas reveals that it consists of methane (similar to 52 %-similar to 99 %) with higher hydrocarbon (0 %-similar to 12 %) and traces of CO2. The manuscript is designed to recognise the stable isotopes of coalbed gas samples using machine learning approaches and then provide a critical review of the gas origin from Jharia Coalfield. The artificial neural network (ANN) was constructed for this purpose, consisting of six parameters as the input and three as the model's output. The stable isotopes of coalbed gas samples from Jharia Coalfield were predicted by the model with the following ranges: -59.86 parts per thousand <= delta C-13-CH4 <=-19.31 parts per thousand, -19.93 parts per thousand <= delta C-13-CO2 <=-7.95 parts per thousand, while -275.74 parts per thousand <= delta D-CH4 <=-138.64 parts per thousand. The wide range of isotope data imitates the complicated generation mechanism of coalbed gas; both thermogenic and biogenic methane are present in the coalbed gas. The carbon dioxide and methane index (CDMI), hydrocarbon index (HI), and gas dryness index (DI) were determined for the description of the Bernard and CD diagram (carbon-hydrogen diagram or Whiticar-style plot) to infer the origin of coalbed gas from the Jharia Coalfield. The experiment of the stable isotope analysis of the coalbed gas was also performed, which augmented the ANN-based prediction of stable isotopes by providing a strong correlation (R-2>0.99). Van Krevelen's diagram concludes that the coal samples fall in the window of type III gas origin. This research provides fundamental insights into the generation mechanism of clean energy coalbed gas

Contamination of water bodies with radioactive heavy metals such as thorium (Th(IV)) and uranium (U(VI)) poses significant risks to human health and the environment. Developing sustainable and efficient technologies for their removal is therefore critical for environmental protection and resource recovery. In this study, a fly ash-derived zeolite-hydroxyapatite (HApZ) composite was synthesized via a one-step hydrothermal method at three different temperatures: 50 degrees C (HApZ(50)), 100 degrees C (HApZ(100)), and 150 degrees C (HApZ(150)). The hydrothermal temperature significantly influenced the crystallinity, morphology, and surface area of the composites. Among them, HApZ(100) exhibited the highest surface area (351 m(2) g(-)(1)) and outstanding adsorption capacities of 793 mg g(-)(1) for Th(IV) and 872 mg g(-)(1) for U(VI), owing to the synergistic integration of zeolite and hydroxyapatite phases. The adsorption behavior followed the Langmuir isotherm and pseudo-second-order kinetics, indicating monolayer adsorption and chemisorption as the dominant mechanisms. HApZ(100) demonstrated excellent reusability, retaining 81 % for Th(IV) and 89 % for U(VI) removal efficiency after six regeneration cycles and maintained robust performance even up to ten cycles. Economic assessment confirmed the cost-effectiveness of the HApZ(100) (similar to 33.41 USD per kg) which is substantially lower in price than the activated carbon, ion exchange resin, and other adsorbents. Moreover, HApZ(100) achieved complete removal of Th(IV) and U(VI) from the industrial effluent, even in complex multi-ion systems. These findings underscore the effectiveness of HApZ(100) as a sustainable and promising material for wastewater treatment, environmental remediation, and resource recovery.

Plastics play an indispensable role in daily life due to their durability, light weight, cost-effectiveness, and versatility, making the development of efficient waste management solutions vital for addressing the challenges posed by synthetic plastic disposal at the end of their lifecycle. Plastics, mostly sourced from petroleum-based feedstocks, can be reprocessed into petroleum products by catalytic and hydrothermal techniques. Pyrolysis oil, which predominantly consists of unsaturated hydrocarbons, requires upgrading to saturated aromatic compounds through hydroprocessing for use in vehicle fuel applications. This work introduces an innovative method employing ionic liquid-supported solid catalysts for the hydroprocessing of waste plastics into fuel at low processing temperatures. Specifically, 1-ethyl-3-methylimidazolium triflate (EMIM-OTf) immobilized on mesoporous Ni/SBA-15 was used as a hydroprocessing catalyst. Unlike previous studies requiring high reaction temperatures (300-400 degrees C) with heterogeneous catalysts, our process converted plastic pyrolysis oil to diesel-equivalent fuel at 190 degrees C under 70 bar H2 pressure. GC-MS analysis confirmed olefin conversion into paraffins and the aromatization of reactants, yielding benzene and naphthalene derivatives. The resulting n-paraffins and isoparaffins matched commercial diesel by 95 % and 90 %, respectively, with a 3.65 % increase in aromatics. The physicochemical properties of the hydroprocessed pyrolysis oil (HMP-PO) complied with EN 590 European diesel standards. This study highlights a low-temperature strategy, contributing to energy efficiency and plastic waste mitigation.

Internal lattices used to pack existing catalyst or adsorbent particles have demonstrated significant improvement of performance in reaction and separation processes. In this work, we developed a methodology to customize the column porosity as a function of the column length. The novel expanded structures contribute to control the amount of particles that can be packed in different locations of the lattice. The design of internal lattices and the evaluation of porosities by virtual packing were done digitally for spheres of 2.0 and 3.0 mm. The pressure drop of empty and packed structures was modelled using computational fluid dynamics and has been experimentally confirmed for the different structures used.

Ni-based metal-organic frameworks (Ni-MOFs) have attracted significant attention as electrocatalysts for electrochemical water splitting due to their tunable structure and high surface area. In this study, the catalytic performance of Ni-MOFs was enhanced through Mo-doping at varying concentrations. Three Mo-doped Ni-MOFs were synthesized via a solvothermal method by in situ addition of Mo salt at molar ratios of 10 %, 20 %, and 30 %. Mo incorporation effectively tuned the d-band center of Ni, thereby improving the hydrogen evolution reaction (HER) activity. The Ni-MOF/Mo20 exhibited the best performance, featuring a 3D flower-like morphology composed of stacked 2D nanosheets. It achieved a low overpotential of 185 mV at 10 mA cm-2 and a small Tafel slope of 58 mV dec-1. Additionally, the overpotentials at higher current densities remained moderate-217 mV and 246 mV at 50 and 100 mA cm-2, respectively. The enhanced performance is attributed to the increased density of electrochemically active sites and reduced charge transfer resistance resulting from Mo doping. These findings underscore the potential of Mo-doped Ni-MOFs as efficient electrocatalysts for HER applications.

The effective treatment of oil-contaminated wastewater is a critical environmental challenge. This study demonstrates a robust pathway for synthesizing high-performance activated carbon (AC) from date palm seed waste for the removal of crude oil. A two-step process involving pyrolysis and subsequent KOH chemical activation was systematically optimized by varying key parameters, including temperature, time, and impregnation ratio. The optimized adsorbent, AC5 (prepared at a 4:1 KOH: biochar ratio, 700 °C, for 2 h), exhibited a high surface area of 2151 m²/g and an exceptional crude oil adsorption capacity of 1816 mg/g. A key finding is that maximum surface area alone does not dictate performance for complex adsorbates; AC5 significantly outperformed a sample with a higher surface area (2417 m²/g), a result attributed to its more favorable surface chemistry as confirmed by FTIR analysis. The adsorption process was best described by the Freundlich isotherm and pseudo-second-order kinetic models. Crucially, the performance of the optimized AC represents an improvement of nearly an order of magnitude over previously reported date-seed carbons for oil removal and surpasses that of many other biomass-derived adsorbents. This work establishes a clear synthesis pathway for valorizing an abundant agricultural waste into a superior adsorbent for oil spill remediation.

Optimizing process parameters is essential for developing high efficacy carbonaceous adsorbents. This study investigated carbon dioxide (CO2) capture using activated carbon (AC) synthesized from date-palm leaflets. Key process parameters-pyrolysis temperature, residence time, and KOH-to-carbon (KOH/C) impregnation ratio-were systematically varied to synthesize highly nanoporous AC for enhanced CO2 uptake. Instead of relying on an intuitive selection of process variables, the optimization process was implemented using Response Surface Methodology (RSM) protocol, which provided a structured and effective strategy for process optimization. Over twenty different AC samples were synthesized and evaluated for their CO2 adsorption capacities. The optimal conditions, identified as 700 °C, 1.5 h, and a 3:1 (KOH/C) impregnation ratio, yielded AC with exceptional CO2 uptake capacities of 6.71 mmol/g at 0 °C and 4.214 mmol/g at 25 °C, outperforming most previously reported biomass-derived ACs. This superior performance is attributed to the well-developed nanoporous structure and high nitrogen content of the optimized sample, as confirmed by N2 adsorption isotherms, elemental analysis, scanning electron microscopy (SEM), and Fourier transform infrared spectroscopy (FTIR). The optimized AC demonstrated excellent stability over multiple adsorption-desorption cycles. Additionally, a high isosteric enthalpy of adsorption (35 kJ/mol at 0.2 mmol/g) further confirmed preferential CO2 adsorption at energetically favorable nanopore sites. This study underscores the potential of date-palm leaflets as a sustainable and abundant precursor for synthesizing high-efficacy AC for carbon capture.

Background: A comparative regression modelling of fluidization bed data parameters is performed in this work using different algorithms. Computational fluid dynamics (CFD) modelling of particle and fluid flow characters using two-fluid Eulerian-Eulerian model. RNG k-epsilon turbulence coupled with kinetic theory of granular flow was also combined. The developed numerical model is used for generating the fluidization related data of parameters like turbulent viscosity, turbulent dissipation rate, solid velocity, solid volume fraction, granular temperature, and turbulent kinetic energy. Methods: Comparative modelling and performance analysis between ensemble learning, supervised learning, and neural networks is performed for the mentioned fluidized bed parameters. Ensemble Regression algorithms: Gradient boosting regressor (GBR), Voting regressor (VR), and Random-forest regressor (RFR), supervised learning algorithm - Decision tree (DT), and Deep Artificial neural network (ANN) models are used for the data mapping of fluidization parameters. Performance metrices are accessed in details to compare the modelling results or the algorithms in details for each fluidization parameter. Findings: From the modelling of this data it is found that numerical data is highly non-linear. DT and RFR algorithms are the most accurate algorithms that predicted with >90 % of accuracy in each case. VT and GBR trained and tested with around 85 % accuracy in most cases but failed in prediction of granular temperature. ANN also sufficiently provided good accuracy while it also failed to predict granular temperature. Solid volume fraction, turbulent kinetic energy, turbulent viscosity, and turbulent dissipation rate were modelled perfectly with all the algorithms. Among all the parameters, turbulent viscosity during training and testing from each model is highly accurately modelled from each of the algorithm with prediction accuracy >90 %.

Co3O4/ZnO composite nanostructures were successfully synthesized via a simple hydrothermal method followed by air-based calcination at 500 degrees C. The resulting hexagonal heterostructure composite with a large interfacial area demonstrates exceptional oxygen evolution electrocatalytic activity with an overpotential of 288 mV at 10 mA cm- 2 , and a low Tafel slope (80 mV dec-1). This enhanced activity is attributed to the Co3O4/ZnO p-n junction, where ZnO (an n-type semiconductor) and Co3O4 (a p-type semiconductor) meet, which is crucial for boosting catalytic activity. This interface enables swift electron movement between the two materials, resulting in better charge separation and decreased charge recombination. Additionally, the high active surface area, confirmed by cyclic voltammetry measurements, further contributes to the improved OER performance. The well-defined interfaces within the Co3O4/ZnO heterostructures provide abundant active sites, facilitating efficient charge transfer kinetics. This research highlights the potential of composite heterostructures as promising electrocatalysts for water-splitting applications.