Search Results (417)

This study proposed a mechanochemical activation strategy using ethanol-diisopropanolamine (EDIPA) to improve the grindability and hydration reactivity of basic oxygen furnace slag (BOFS), aiming for its large-scale industrial utilization. The incorporation of EDIPA significantly refined the particle size distribution and reduced the repose angle. As a result, the compressive strength of BOFS paste increased by 25.4 MPa at 28 d with only 0.08 wt.% EDIPA. Conductivity tests demonstrated that EDIPA strongly complexes with Ca²⁺, Al³⁺, and Fe³⁺, facilitating the dissolution of active mineral phases, such as C₁₂A₇ and C₂F, and accelerating hydration reactions. XRD and TG analyses confirmed that the incorporation of EDIPA facilitated the formation of Mc (C₄(A,F)ČH₁₁) and increased the content of C-S-H, both of which contributed to microstructural densification. Microstructural observations further revealed that EDIPA refined Ca(OH)₂ crystals, increasing their specific surface area from 4.7 m²/g to 35.2 m²/g. The combined effect of crystal refinement and enhanced hydration product formation resulted in reduced porosity and improved mechanical properties. Overall, the results demonstrated that EDIPA provided an economical, effective, and scalable means of activating BOFS, thereby promoting its high-value utilization in low-carbon construction materials. Full article

Ternary choline chloride-based deep eutectic solvents (TDESs) exhibit unique physicochemical properties, including lower viscosities, lower melting points, higher thermal stabilities, and enhanced solvations compared to binary deep eutectic solvents (BDESs). Although BDESs have been widely studied, the addition of a third component in TDESs offers opportunities to further optimize their performance. This review aims to evaluate the physicochemical properties of TDESs and highlight their potential applications in sustainable industrial processes compared to BDESs. A comprehensive analysis of the existing literature was conducted, focusing on TDES properties, such as phase behavior, density, viscosity, pH, conductivity, and the effect of water, along with their applications in various fields. TDESs demonstrated superior physicochemical characteristics compared to BDESs, including improved solvation and thermal stability. Their applications in biomass conversion, CO₂ capture, heavy oil upgrading, refrigeration gases, and as solvents/catalysts in organic reactions show significant promise for enhancing process efficiency and sustainability. Despite their advantages, TDESs face challenges including limited predictive models, potential instability under certain conditions, and scalability hurdles. Overall, TDESs offer significant potential for advancing sustainable and efficient chemical processes for industrial applications. Full article

Industrial catalysts are accelerating the global transition toward renewable energy, serving as enablers for innovative technologies that enhance efficiency, lower costs, and improve environmental sustainability. This review explores the pivotal roles of industrial catalysts in hydrogen production, biofuel generation, and biomass conversion, highlighting their transformative impact on renewable energy systems. Precious-metal-based electrocatalysts such as ruthenium (Ru), iridium (Ir), and platinum (Pt) demonstrate high efficiency but face challenges due to their cost and stability. Alternatives like nickel-cobalt oxide (NiCo₂O₄) and Ti₃C₂ MXene materials show promise in addressing these limitations, enabling cost-effective and scalable hydrogen production. Additionally, nickel-based catalysts supported on alumina optimize SMR, reducing coke formation and improving efficiency. In biofuel production, heterogeneous catalysts play a crucial role in converting biomass into valuable fuels. Co-based bimetallic catalysts enhance hydrodeoxygenation (HDO) processes, improving the yield of biofuels like dimethylfuran (DMF) and γ-valerolactone (GVL). Innovative materials such as biochar, red mud, and metal–organic frameworks (MOFs) facilitate sustainable waste-to-fuel conversion and biodiesel production, offering environmental and economic benefits. Power-to-X technologies, which convert renewable electricity into chemical energy carriers like hydrogen and synthetic fuels, rely on advanced catalysts to improve reaction rates, selectivity, and energy efficiency. Innovations in non-precious metal catalysts, nanostructured materials, and defect-engineered catalysts provide solutions for sustainable energy systems. These advancements promise to enhance efficiency, reduce environmental footprints, and ensure the viability of renewable energy technologies. Full article

Background: Precision medicine refers to the formulation of personalized drug regimens according to the individual characteristics of patients to achieve optimal efficacy and minimize adverse reactions. Additive manufacturing (AM), also known as three-dimensional (3D) printing, has emerged as an optimal solution for precision drug delivery, enabling customizable and the fabrication of multifunctional structures with precise control over morphology and release behavior in pharmaceutics. However, the influence of 3D printing parameters on the printed tablets, especially regarding in vitro and in vivo performance, remains poorly understood, limiting the optimization of manufacturing processes for controlled-release profiles. Objective: To establish the fabrication process of 3D-printed controlled-release tablets via comprehensively understanding the printing parameters using fused deposition modeling (FDM) combined with hot-melt extrusion (HME) technologies. HPMC-AS/HPC-EF was used as the drug delivery matrix and carbamazepine (CBZ) was used as a model drug to investigate the in vitro drug delivery performance of the printed tablets. Methodology: Thermogravimetric analysis (TGA) was employed to assess the thermal compatibility of CBZ with HPMC-AS/HPC-EF excipients up to 230 °C, surpassing typical processing temperatures (160–200 °C). The formation of stable amorphous solid dispersions (ASDs) was validated using differential scanning calorimetry (DSC), hot-stage polarized light microscopy (PLM), and powder X-ray diffraction (PXRD). A 15-group full factorial design was then used to evaluate the effects of the fan speed (20–100%), platform temperature (40–80 °C), and printing speed (20–100 mm/s) on the tablet properties. Response surface modeling (RSM) with inverse square-root transformation was applied to analyze the dissolution kinetics, specifically t_50% (time for 50% drug release) and Q_4h (drug released at 4 h). Results: TGA confirmed the thermal compatibility of CBZ with HPMC-AS/HPC-EF, enabling stable ASD formation validated by DSC, PLM, and PXRD. The full factorial design revealed that printing speed was the dominant parameter governing dissolution behavior, with high speeds accelerating release and low speeds prolonging release through porosity-modulated diffusion control. RSM quadratic models showed optimal fits for t_50% (R² = 0.9936) and Q_4h (R² = 0.9019), highlighting the predictability of release kinetics via process parameter tuning. This work demonstrates the adaptability of polymer composite AM for tailoring drug release profiles, balancing mechanical integrity, release kinetics, and manufacturing scalability to advance multifunctional 3D-printed drug delivery devices in pharmaceutics. Full article

This study demonstrates the successful fabrication of high-performance reaction-bonded silicon carbide (RBSC) ceramics through an optimized liquid silicon infiltration (LSI) process employing multi-modal SiC particle gradation and nano-carbon black (0.6 µm) additives. By engineering porous preforms with hierarchical SiC distributions and tailored carbon sources, the resulting ceramics achieved a compressive strength of 2393 MPa and a flexural strength of 380 MPa, surpassing conventional RBSC systems. Microstructural analyses revealed homogeneous β-SiC formation and crack deflection mechanisms as key contributors to mechanical enhancement. Ultrafine SiC particles (0.5–2 µm) refined pore architectures and mediated capillary dynamics during infiltration, enabling nanoscale dispersion of residual silicon phases and minimizing interfacial defects. Compared to coarse-grained counterparts, the ultrafine SiC system exhibited a 23% increase in compressive strength, attributed to reduced sintering defects and enhanced load transfer efficiency. This work establishes a scalable strategy for designing RBSC ceramics for extreme mechanical environments, bridging material innovation with applications in high-stress structural components. Full article

This study investigates the synergistic modification of cement–soil using waste brick powder (WBP) and polyvinyl alcohol (PVA) fibers to address the growing demand for sustainable construction materials and recycling of demolition waste. An orthogonal experimental design was employed with 5% WBP (by mass) and PVA fiber content (0–1%), evaluating mechanical properties based on unconfined compressive strength (UCS) and splitting tensile strength (STS) and microstructure via scanning electron microscopy (SEM) across 3–28 days of curing. The results demonstrate that 0.75% PVA optimizes performance, enhancing UCS by 28.3% (6.87 MPa) and STS by 34.6% (0.93 MPa) at 28 days compared to unmodified cement–soil. SEM analysis revealed that PVA fibers bridged microcracks, suppressing propagation, while WBP triggered pozzolanic reactions to densify the matrix. This dual mechanism concurrently improves mechanical durability and valorizes construction waste, offering a pathway to reduce reliance on virgin materials. This study establishes empirically validated mix ratios for eco-efficient cement–soil composites, advancing scalable solutions for low-carbon geotechnical applications. By aligning material innovation with circular economy principles, this work directly supports global de-carbonization targets in the construction sector. Full article

Hydrogen energy is a pivotal carrier for achieving carbon neutrality, requiring green and efficient production via water electrolysis. However, the anodic oxygen evolution reaction (OER) involves a sluggish four-electron transfer process, resulting in high overpotentials, while the prohibitive cost and complex preparation of precious metal catalysts impede large-scale commercialization. In this study, we develop a FeCo-based bimetallic deep eutectic solvent (FeCo-DES) as a multifunctional reaction medium for engineering a three-dimensional (3D) coral-like FeOOH-Co₂(OH)₃Cl/NF composite via a mild one-step impregnation approach (70 °C, ambient pressure). The FeCo-DES simultaneously serves as the solvent, metal source, and redox agent, driving the controlled in situ assembly of FeOOH-Co₂(OH)₃Cl hybrids on Ni(OH)₂/NiOOH-coated nickel foam (NF). This hierarchical architecture induces synergistic enhancement through geometric structural effects combined with multi-component electronic interactions. Consequently, the FeOOH-Co₂(OH)₃Cl/NF catalyst achieves a remarkably low overpotential of 197 mV at 100 mA cm⁻² and a Tafel slope of 65.9 mV dec⁻¹, along with 98% current retention over 24 h chronopotentiometry. This study pioneers a DES-mediated strategy for designing robust composite catalysts, establishing a scalable blueprint for high-performance and low-cost OER systems. Full article

The rapid increase in polystyrene (PS) production has led to substantial growth in plastic waste, posing serious environmental and waste management challenges. Current disposal techniques are unsustainable, relying heavily on harsh conditions, high energy input, and generating environmentally harmful byproducts. This review critically discusses alternative green approaches for PS treatment through photocatalytic and non-photocatalytic upcycling methods. Photocatalytic methods utilize light energy (UV, visible, or broad-spectrum irradiation) to initiate radical reactions that cleave the inert carbon backbone of PS. In contrast, non-photocatalytic strategies achieve backbone degradation without direct light activation, often employing catalysts and thermal energy. Both approaches effectively transform PS waste into higher-value compounds, such as benzoic acid and acetophenone, though yields remain moderate for most reported methods. Current limitations, including catalyst performance, low yields, and impurities in real-world PS waste, are highlighted. Future directions toward enhancing the efficiency, selectivity, and scalability of PS upcycling processes are proposed to address the growing plastic waste crisis sustainably. Full article

This study presents a cost-effective, carbon-negative construction material for affordable housing, developed entirely from locally available agricultural wastes: rice husk ash, wood ash, and rice straw—materials often problematic to dispose of in many African regions. Rice husk ash provides high amorphous silica, acting as a strong pozzolanic agent. Wood ash contributes calcium oxide and alkalis to serve as a reactive binder, while rice straw functions as a lightweight organic filler, enhancing thermal insulation and indoor climate comfort. These materials undergo natural pozzolanic reactions with water, eliminating the need for Portland cement—a major global source of anthropogenic CO₂ emissions (~900 kg CO₂/ton cement). This process is inherently carbon-negative, not only avoiding emissions from cement production but also capturing atmospheric CO₂ during lime carbonation in the hardening phase. Field trials in Kenya confirmed the composite’s sufficient structural strength for low-cost housing, with added benefits including termite resistance and suitability for unskilled laborers. In a collaboration between the University of Tartu and Kenyatta University, a semi-automatic mixing and casting system was developed, enabling fast, low-labor construction of full-scale houses. This innovation aligns with Kenya’s Big Four development agenda and supports sustainable rural development, post-disaster reconstruction, and climate mitigation through scalable, eco-friendly building solutions. Full article

Despite significant progress in photoelectrochemical (PEC) water splitting, high fabrication costs and limited efficiency of photoanodes hinder practical applications. Bismuth vanadate (BiVO₄), with its low cost, non-toxicity, and suitable band structure, is a promising photoanode material but suffers from poor charge transport, sluggish surface kinetics, and photocorrosion. In this study, porous monoclinic BiVO₄ films are fabricated via a simplified successive ionic layer adsorption and reaction (SILAR) method, followed by borate treatment and PEC deposition of NiFeO_x. The resulting B/BiVO₄/NiFeO_x photoanode exhibits a significantly enhanced photocurrent density of 2.45 mA cm⁻² at 1.23 V vs. RHE—5.3 times higher than pristine BiVO₄. It also achieves an ABPE of 0.77% and a charge transfer efficiency of 79.5%. These results demonstrate that dual surface modification via borate and NiFeO_x is a cost-effective strategy to improve BiVO₄-based PEC water splitting performance. This work provides a promising pathway for the scalable development of efficient and economically viable photoanodes for solar hydrogen production. Full article

The article describes a simple and scalable preparation of 2-monothiacalix[4]arene 7, the simplest representative of the mixed-bridged (CH₂ and S) calix[4]arenes. The synthesis is based on the condensation of linear building blocks (bisphenols), which are relatively readily available, and allows, depending on the conditions, the use of two alternative reaction routes that provide macrocycle 7 in high yield. The dynamic behavior of the basic macrocyclic skeleton was investigated using NMR spectroscopy at variable temperatures. High-temperature measurements showed that compound 7 undergoes a cone–cone equilibrium with activation free energy ΔG^# of the inversion process of 63 kJ·mol⁻¹. Interestingly, the same barrier for the oxidized sulfone derivative 14 shows a value of 60 kJ·mol⁻¹, indicating weakened hydrogen bonds at the lower rim of the calixarene. The same was also confirmed at low temperatures, when barriers to changing the direction of the cyclic hydrogen bond arrays (flip-flop mechanism) were determined (compare ΔG^# = 44 kJ·mol⁻¹ for 7 vs. ΔG^# = 40 kJ·mol⁻¹ for 14). Full article

Esterification is a key transformation in the production of lubricants, pharmaceuticals, and fine chemicals. Conventional processes employing homogeneous acid catalysts suffer from limitations such as corrosive byproducts, energy-intensive separation, and poor catalyst reusability. This review provides a comprehensive overview of heterogeneous catalytic systems, including ion exchange resins, zeolites, metal oxides, mesoporous materials, and others, for improved ester synthesis. Recent advances in membrane-integrated reactors, such as pervaporation and nanofiltration, which enable continuous water removal, shifting equilibrium and increasing conversion under milder conditions, are reviewed. Dual-functional membranes that combine catalytic activity with selective separation further enhance process efficiency and reduce energy consumption. Enzymatic systems using immobilized lipases present additional opportunities for mild and selective reactions. Future directions emphasize the integration of pervaporation membranes, hybrid catalyst systems combining biocatalysts and metals, and real-time optimization through artificial intelligence. Modular plug-and-play reactor designs are identified as a promising approach to flexible, scalable, and sustainable esterification. Overall, the interaction of catalyst development, membrane technology, and digital process control offers a transformative platform for next-generation ester synthesis aligned with green chemistry and industrial scalability. Full article

Background/Objectives: Norovirus is a major cause of acute gastroenteritis worldwide. Considering its highly infectious and transmissible nature, rapid and accurate diagnostic tools are of utmost importance for the effective control of outbreaks in the context of point-of-care testing (POCT). In this study, we developed a genogroup-specific multiplex reverse transcriptase loop-mediated isothermal amplification assay to detect the human norovirus genogroups I and II (GI and GII, respectively). Methods: For the comprehensive detection of clinically relevant genotypes, two sets of primers were incorporated into the assays targeting the RdRp-VP1 junction: one against GI.1 and GI.3, and the other for GII.2 and GII.4. Following optimization of the reaction variables, we standardized the reaction conditions at 65 °C with 6 mM MgSO₄, 1.4 mM dNTPs, 7.5 U WarmStart RTx Reverse Transcriptase, and Bst DNA polymerase at 8 U and 10 U for GI and GII, respectively. Amplification was monitored in real-time using a thermocycler platform to ensure precise quantification and detection. Finally, the assay was evaluated through portable isothermal detection device to test its feasibility in on-site settings. Results: Both assays detected the template down to 10²–10³ copies per reaction and showed high target selectivity, yielding no non-specific amplification across 39 enteric pathogens. These assays enabled prompt detection of GI within 10–12 min and of GII within 12–17 min after the reaction was initiated. Onsite validation reveals all template detection below 15 min, demonstrating its potential feasibility in point-of-care applications. Including the sample preparation time, test results were obtained in less than 1 h. Conclusions: This method is a rapid, reliable, and scalable solution for detecting human norovirus in POCT settings for both clinical diagnosis and public health surveillance. Full article

Infectious diseases poses a growing public health challenge. The COVID-19 pandemic has further emphasized the urgent need for rapid, accessible diagnostics. This study presents the development of an integrated, flexible point-of-care (POC) diagnostic system for the rapid detection of Corynebacterium diphtheriae, the pathogen responsible for diphtheria. The system comprises a microfluidic polymerase chain reaction (micro-PCR) device and an electrochemical DNA biosensor, both fabricated on flexible substrates. The micro-PCR platform offers rapid DNA amplification overcoming the time limitations of conventional thermocyclers. The biosensor utilizes specific molecular recognition and an electrochemical transducer to detect the amplified DNA fragment, providing a clear and direct indication of the pathogen’s presence. The combined system demonstrates the effective amplification and detection of a gene fragment from a toxic strain of C. diphtheriae, chosen due to its increasing incidence. The design leverages lab-on-a-chip (LOC) and microfluidic technologies to minimize reagent use, reduce cost, and support portability. Key challenges in microsystem design—such as flow control, material selection, and reagent compatibility—were addressed through optimized fabrication techniques and system integration. This work highlights the feasibility of using flexible, integrated microfluidic and biosensor platforms for the rapid, on-site detection of infectious agents. The modular and scalable nature of the system suggests potential for adaptation to a wide range of pathogens, supporting broader applications in global health diagnostics. The approach provides a promising foundation for next-generation POC diagnostic tools. Full article

Nanoparticles (NPs) synthesised through biogenic routes have emerged as a sustainable and innovative platform for biomedical applications such as antibacterial, anticancer, antiviral, anti-inflammatory, drug delivery, wound healing, and imaging diagnostics. Among these, silver nanoparticles (AgNPs) have attracted significant attention due to their unique physicochemical properties and therapeutic potential. This review examines the biogenic synthesis of AgNPs, focusing on microbial, plant-based, and biomolecule-assisted approaches. It highlights how reaction conditions, such as pH, temperature, and media composition, influence nanoparticle size, shape, and functionality. Particular emphasis is placed on microbial synthesis for its eco-friendly and scalable nature. The mechanisms of AgNP formation and their structural impact on biomedical performance are discussed. Key applications are examined including antimicrobial therapies, cancer treatment, drug delivery, and theranostics. Finally, the review addresses current challenges, such as reproducibility, scalability, morphological control, and biosafety, and outlines future directions for engineering AgNPs with tailored properties, paving the way for sustainable and effective next-generation biomedical solutions. Full article