Search Results (2,449)

This work reports the controlled synthesis and characterization of nanoenergetic composites composed of porous silicon (PS) impregnated with sodium perchlorate (NaClO₄) for precision energy-release applications. PS films were fabricated by electrochemical anodization of p-type silicon (10–20 Ω·cm), with systematic variation in current density (50–200 mA cm⁻²) and anodization time (10–25 min) to tailor pore morphology. The energetic behavior of the composites was evaluated through thermal ignition tests, optical emission spectroscopy (300–1000 nm), acoustic analysis (0–500 Hz), and high-speed imaging. Optimal energy release was obtained for PS films anodized at 100 mA cm⁻² for 15–20 min, attributed to their hierarchical pore architecture that facilitated complete oxidant infiltration. Overall, this work provides additional insights beyond previous reports by correlating the explosive efficiency with both anodization time—linked to PS film thickness—and current density—associated with porosity. A portable multispectral optical system with fiber-optic access to the explosion chamber was developed for in situ characterization, offering a safe and versatile approach for measurements in explosive environments. To the best of our knowledge, no prior studies have analyzed the correlation between the acoustic signatures and explosion intensity in PS–NaClO₄ systems as proposed here. Full article

Hydrometallurgy is currently the mainstream industrial process for recovering valuable components (nickel, cobalt, manganese, lithium, etc.) from spent ternary lithium-ion battery cathode materials. During the crushing of lithium batteries, cathode materials, anode materials (graphite), and electrolytes become mixed. Consequently, fluoride ions inevitably enter the leaching solution during the hydrometallurgical recycling process, with concentrations as high as 100–300 mg/L. These fluoride ions not only adversely affect the quality of the recovered precursor products but also pose environmental risks. To address this issue, this study employs a synthesized lanthanum–zirconium (La@Zr) composite material, with a specific surface area of 67.41 m²/g and a pore size of 2–50 nm, which can reduce the fluoride ion concentration in the leaching solution to below 5 mg/L, significantly lower than the 20 mg/L or higher that is typically achieved with traditional calcium salt defluorination processes, without introducing new impurities. Under optimal adsorption conditions, the lanthanum–zirconium adsorbent exhibits a fluoride ion adsorption capacity of 193.4 mg/g in the leaching solution, surpassing that of many existing metal-based adsorbents. At the same time as the valuable metals, Li, Ni, and Co, are basically not adsorbed, the selective adsorption of fluoride ions can be achieved. Adsorption isotherm studies indicate that the adsorption process follows the Langmuir model, suggesting monolayer adsorption. The secondary adsorption process is primarily governed by chemical adsorption, and elevated temperatures facilitate the removal of fluoride ions. Kinetic studies demonstrate that the adsorption process is well described by the pseudo-second-order model. After desorption and regeneration with NaOH solution, the adsorbent still has a favorable fluoride removal performance, and the adsorption rate of fluoride ions can still reach 95% after four cycles of use. With its high capacity, rapid kinetics, and excellent selectivity, the adsorbent is highly promising for large-scale implementation. Full article

This study investigates the physicochemical processes in aqueous solutions treated with a high-current (up to 300 A) pulsed multispark discharge. Pulse length was 2 μs at a 50 Hz repetition rate. The discharge occurred within bubbles of argon injected between the stainless-steel electrodes at the constant flow rate. The erosion of electrode material during the discharge led to iron and other alloy components entering the liquid. Optical emission spectra confirmed the erosion of electrode material (Fe, Cr, Ni atoms and ions). EDTA and its disodium salt were used in order to study their effect on the metal particle formation process. Treatment with deionized water led to an increase in conductivity and the generation of hydrogen peroxide (up to 1200 µM). In contrast, the presence of EDTA and its disodium salt drastically altered the reaction pathways: the H₂O₂ yield decreased, and the solution conductivity dropped substantially for the acidic form of EDTA, while the decrease was minor for EDTA-Na₂. This effect is attributed to the buffered chelation of eroded metal ions, forming stable Fe-EDTA complexes, as confirmed by a characteristic absorption band at 260 nm. The results demonstrate the critical role of complex-forming agents in modulating plasma–liquid interactions, shifting the process from direct erosion products to the formation of stable coordination compounds. Full article

Developing highly efficient and stable electrocatalysts from inexpensive and earth-abundant elements represents a significant advancement in overall water splitting (OWS). This study focuses on the synthesis and evaluation of palladium-modified cobalt–phosphorus (PdCoP) and cobalt–iron–phosphorus (PdCoFeP) coatings for use as electrocatalysts in hydrogen evolution (HER), oxygen evolution (OER) and overall water splitting (OWS) in alkaline media. A facile electroless plating method is adopted to deposit the CoP and CoFeP coatings onto a copper surface (Cu sheet), with sodium hypophosphite (NaH₂PO₂) acting as the reducing agent. Pd crystallites were incorporated on CoP and CoFeP coatings using the galvanic displacement method. This study details morphological characterization (using SEM, EDX, and XRD), as well as electrochemical activity testing, for both HER and OER using linear sweep voltammetry (LSV) at different temperatures. The stability of the catalysts for HER was evaluated using chronoamperometry (CA) and chronopotentiometry (CP). The results show that the Pd-modified CoFeP and CoP catalysts exhibited lower overpotentials of 207 and 227 mV, respectively, for HER and 396 mV for OER at a current density of 10 mA cm⁻² compared to the unmodified CoFeP and CoP catalysts. The innovation achieved in this study lies in combining a facile, low-cost deposition method (electroless plating followed by galvanic displacement) with a novel, highly effective ternary composition (PdCoFeP) that exploits synergistic electronic and morphological effects to achieve superior bifunctional performance for alkaline OWS, achieving a low cell voltage of 1.69 V at a current density of 10 mA cm⁻². Overall, this research demonstrates that these synthesized materials are promising candidates for sustainable and economical hydrogen production. Full article

Geopolymer materials possess several outstanding advantages, including the wide availability of raw materials, an energy-saving and environmentally friendly production process, and excellent engineering technical performance. They are regarded as a new type of green building material that can achieve high-value-added resource utilization of industrial solid waste. They are one of the current research hotspots in the field of materials. Fly ash and slag, the most common industrial wastes in China, have been discharged in large quantities, significantly impacting the country’s ecological environment. Based on this, this paper primarily investigates the mechanical properties and strength formation mechanism of geopolymer paste to develop geopolymer materials with enhanced mechanical properties. This research uses metakaolin as the silicate raw material and uses sodium silicate mixed with NaOH as the alkali activator to prepare geopolymer paste. By adding fly ash and slag, the mechanical properties of the geopolymer paste are improved. The effects of the alkali activator modulus, Na₂O equivalent, and content of fly ash and slag on the setting time and strength of geopolymer paste are studied. XRD, FTIR, and SEM are employed to characterize the phase, molecular structure, and microscopic morphology of geopolymer paste, as well as to analyze the microstructure and reaction mechanism of these materials. The results show that the setting time of the geopolymer increases with the increase in modulus and shortens with the increase in Na₂O equivalent. Fly ash and slag, respectively, act as retarders and early strength promoters. The ratio of n(SiO₂)/n(A1₂O₃) (that is, the modulus of the alkali activator) of the geopolymer is an important factor affecting its strength. The metakaolin and fly ash–slag–metakaolin exhibit the best mechanical properties when their molar ratios are 2.97 and 3.26, respectively. Through microscopic characterization using XRD, FTIR, and SEM, it is observed that fly ash–slag–metakaolin exhibits the most complete polymerization reaction, generates the most amorphous silicate aluminosilicate gel, and displays the best inter-gel bonding effect, resulting in the best mechanical properties. Full article

Background/Objectives: Influenza A virus undergoes continuous antigenic drift, necessitating annual vaccine reformulation. Saudi Arabia faces unique epidemiological challenges owing to mass gatherings during religious pilgrimages and the dynamic movement of foreign workers. This study aimed to characterize the genetic diversity of hemagglutinin (HA) and neuraminidase (NA) genes of influenza A viruses circulating in Riyadh and to assess their match with vaccine strains during the 2024–2025 period. Methods: Nasopharyngeal samples (n = 363) were collected from patients presenting with influenza-like illness. RT-PCR was used for detection and subtyping. Sequence and phylogenetic analysis of the complete HA and NA gene sequences from A/H1N1pdm09 strains (n = 7) were then performed. Results: Of the 363 samples, 110 (30.3%) were positive for influenza A; among these, 68 (61.8%) were A/H1N1pdm09, and 42 (38.2%) were H3N2. Phylogenetic analysis revealed that all A/H1N1pdm09 strains belonged to clade 5a.1, distinct from vaccine strains. In comparison with the vaccine strain A/Wisconsin/67/2022, seven amino acid substitutions in the HA gene and eight in the NA gene were recorded in Saudi circulating strains. The significant genetic divergence between circulating A/H1N1pdm09 strains and current vaccine strains indicates potential vaccine mismatch. Conclusions: The significant genetic divergence between circulating A/H1N1pdm09 strains and current vaccine strains suggests potential vaccine mismatch. Continuous surveillance programs along with vaccination plans are necessary to tackle the changing influenza A virus strains in the special epidemiological context of Saudi Arabia. Full article

(Bi_0.5Na_0.5)TiO₃-based lead-free ferroelectric ceramics are among the most extensively researched energy storage materials today. In this paper, (1 − x)Bi_0.46Sr_0.06Na_0.5TiO_3−xCaTiO₃ ceramics were synthesized through a solid-phase sintering method by synergistically adjusting CaTiO₃ components after introducing Sr²⁺ at the A-site. The XRD patterns revealed that all samples formed a single perovskite solid solution, with the 111 and 200 peaks shifting to higher levels as the CaTiO₃ increased, indicating a gradual decrease in cell volume. The SEM images exhibited dense crystals without any apparent porosity, which were formed by the different components of the ceramics. Through energy storage, dielectric, and charge–discharge performance tests, it was found that with a 10%mol CaTiO₃ addition, the samples obtained a maximum breakdown field strength of 260 kV/cm and corresponding saturation polarization strength of 32.80 μC/cm² and thereby exhibited a reversible energy storage density valued 3.52 J/cm³. In addition, the dielectric constant varied by less than 10% within the temperature range of 63.7 °C to 132.7 °C and presented good frequency (10–250 Hz) stability at 180 kV/cm. Moreover, the ceramics demonstrated a maximum current density reaching 349.58 A/cm² and a maximum power density of 18.90 MW/cm³ for their charge–discharge performance, all of which makes them suitable for pulse system applications. Full article

The high-efficiency and clean utilization of coal resources is a key strategy for new energy development, and converting coal into carbon materials offers a promising route to valorize bituminous coal. However, fabricating high-performance bituminous coal-derived carbon for sodium ion (Na⁺) insertion/extraction remains a major challenge, as it is difficult to regulate the carbon’s microstructural properties to match Na⁺ storage demands. Herein, we propose a molten salt-assisted carbonization strategy to prepare bituminous coal-derived hard carbon (HC) for use as a sodium-ion battery (SIB) anode material, and we focus on regulating the structure of carbon. The results show that as-prepared HC exhibits significantly enhanced electrochemical performance for Na⁺ storage when the molar ratio of NaCl to KCl is 1:1. The optimized material achieves a reversible capacity of 366.7 mAh g⁻¹ at the current density of 100 mA g⁻¹ after 60 cycles and retains 99% of its initial capacity after 500 cycles at a current density of 1 A g⁻¹. The main finding is that the lattice spacing can be regulated by tuning the composition of the molten salt, and anode performance is enhanced remarkably by changes in the HC structure. This work provides a feasible strategy for designing and preparing a bituminous coal-derived carbon anode material for use in the energy storage field. Full article

The discharge of dye-laden effluents remains an environmental challenge since conventional treatments remove color but not the organic load. This study systematically compared anodic oxidation (AO), electro-Fenton (EF), and photoelectro-Fenton (PEF) processes for three representative industrial dyes, such as Coriasol Red CB, Brown RBH, and Blue VT, and their ternary mixture, using boron-doped diamond (BDD) and Ti/IrO₂–SnO₂–Sb₂O₅ (MMO) anodes. Experiments were conducted in a batch reactor with 50 mM Na₂SO₄ at pH = 3.0 and current densities of 20–60 mA cm⁻². Kinetic analysis showed that AO-BDD was most effective at low pollutant loads, EF-BDD became superior at medium loads due to efficient H₂O₂ electrogeneration, and PEF-MMO dominated at higher loads by fast UVA photolysis of surface Fe(OH)²⁺ complexes. In a ternary mixture of 120 mg L⁻¹ of dyes, EF-BDD and PEF-MMO achieved >98% decolorization in 22–23 min with pseudo-first-order rate constants of 0.111–0.136 min⁻¹, whereas AO processes remained slower. COD assays revealed partial mineralization of 60–80%, with EF-BDD providing the most consistent reduction and PEF-MMO minimizing treatment time. These findings confirm that decolorization overestimates efficiency, and electrode selection must be tailored to dye structure and effluent composition. Process selection rules allow us to conclude that EF-BDD is the best robust dark option, and PEF-MMO, when UVA is available, offers practical guidelines for cost-effective electrochemical treatment of textile wastewater. Full article

High-performance self-powered ultraviolet (UV) photodetectors (PDs) based on mixed-dimensional 3D BiOCl nanosheet array/2D ZnO nanoparticle films heterojunction were fabricated via facile spin-coating and impregnation methods. Under zero bias, compared to the pristine ZnO PD exhibiting a large dark current (≈2 μA) and slow response time (>20 s/>20 s), the optimized 2-BiOCl-ZnO heterojunction PD demonstrated a dramatically suppressed dark current (≈1 nA), along with an ultrahigh on/off ratio (22,748) and a shorter response time (17.44 ms/14 ms) under 365 nm light illumination. This optimized device also achieved a remarkable responsivity of 1.08 A·W⁻¹ and a detectivity of 2.48 × 10¹³ Jones at 354 nm. The built-in electric field formed at the BiOCl-ZnO heterojunction interface, the improved light absorption enabled by the mixed-dimensional heterostructure, and the optimized charge carrier separation and transport within the device were responsible for the enhanced self-powered performance. Due to its fascinating photoelectric properties, this PD was applied as a self-powered signal receiver in a UV optical communication system, demonstrating the ability to achieve efficient and high-speed message transmission. The rational construction of BiOCl-based heterojunction has proved to be an efficient pathway to achieving self-powered photodetection. These results demonstrate that the rational construction of heterojunctions holds great potential for fabricating high-performance PDs. Full article

Fe₄₂Mn₂₈Cr₁₅Co₁₀Si₅ is a highly strain-hardenable high-entropy alloy (HEA) that is challenging to machine with traditional metal cutting tools. The electrochemical behavior of this HEA was examined in nitrate- and chloride-based electrolytes to understand the electrochemical machining (ECM) process. Potentiodynamic and potentiostatic tests were conducted on this alloy in 1 M and 2.35 M NaNO₃ solutions, with and without additions of 0.01 M nitric acid and 0.01 M citric acid. A 20% NaCl solution was also tested as an electrolyte. Nitrate solutions caused passivation of the HEA, while no passivation was observed in chloride solutions. Surface analysis with X-ray photoelectron spectrometry (XPS) indicated that adding citric acid helped reduce surface passivation. The Faradaic efficiency of ECM increased with higher applied voltage. The chloride solution showed higher Faradaic efficiency than nitrate-based solutions. Specifically, the Faradaic efficiency of 20% NaCl at 10 V is 57.4%, compared to 21.9% for 20% NaNO₃ + 0.01 M citric acid at 10 V. Electrochemical parameters, including anodic and cathodic exchange current densities, Tafel slopes, and corrosion current densities, were calculated from the experimental data. The corrosion current densities in the 20% nitrate solutions ranged from 2.35 to 3.2 × 10⁻⁵ A/cm², while the 20% chloride solution had a lower corrosion rate at 1.45 × 10⁻⁵ A/cm². These electrochemical parameters can help predict the dissolution behavior of the HEA in nitrate and chloride solutions and aid in optimizing the ECM process. Full article

This study investigates the influence of magnetic fields on the electrochemical corrosion behavior of aerospace-grade H62 brass alloy in 3.5 wt% NaCl solution and its underlying 10 mechanisms. Employing electrochemical testing techniques combined with surface characterization methods, we explored the effects of magnetic field intensity (25–100 mT) and orientation (parallel and perpendicular to electrode surface) on the corrosion kinetics and corrosion product evolution of H62 brass alloy. Results demonstrate that magnetic fields significantly accelerate the corrosion process of H62 brass alloy. Under parallel magnetic field (100 mT), the corrosion current density increased from 0.49 μA/cm² to 3.66 μA/cm², approximately 7.5 times that of the non-magnetic condition, while perpendicular magnetic field increased it to 1.73 μA/cm², approximately 3.5 times the baseline value. The charge transfer resistance decreased from 3382 Ω·cm² to 1335 Ω·cm². Magnetic field orientation determines the fundamental differences in corrosion acceleration mechanisms. Parallel magnetic fields primarily enhance mass transfer processes through Lorentz force-driven magnetohydrodynamic (MHD) effects, resulting in intensified uniform corrosion; perpendicular magnetic fields alter interfacial ion distribution through magnetic gradient forces, inducing localized corrosion tendencies. Magnetic fields promote the transformation of protective Cu₂O films into porous Cu₂(OH)₃Cl, reducing the protective capability of corrosion product layers. Full article

This work introduces a novel approach to enhancing the performance of zinc anodes in zinc–air batteries through a photopolymerizable organic–inorganic hybrid coating. Electrochemical tests were conducted in a neutral NaCl electrolyte, selected to minimize electrolyte carbonation, anode corrosion, and zinc dendrite formation. The behavior of bare and coated zinc electrodes was investigated using linear sweep voltammetry, electrochemical impedance spectroscopy (EIS), potentiostatic measurements, galvanostatic discharge tests, and charge-discharge tests, while morphological and structural characterizations were carried out by Atomic Force Microscopy (AFM), Raman spectroscopy, and X-ray Diffraction (XRD). The results confirmed that the hybrid coating acts as a corrosion-resistant barrier, enhancing the reversibility and stability of zinc electrodes through a barrier mechanism. Charge–discharge tests further confirmed the improved performance of the coated electrode, obtaining at a current density of 1 mA/cm², a coulombic efficiency of 92.61% and a capacity retention of 90.18%, respectively, after 16 cycles. These findings highlight the effectiveness of the photopolymerizable hybrid coating in improving the durability and rechargeability of zinc–air batteries. Full article

Background: Longfin batfish (Platax teira) is an important economic species in southern China. In recent years, its wild population has significantly declined due to overfishing. Around 2015, breakthroughs in the artificial large-scale seedling technology for P. teira have promoted the growth of its aquaculture scale in regions such as Hainan and Guangdong. Methods: To study the genetic diversity, inbreeding status, and population structure of the current P. teira farming populations in China, we performed whole-genome resequencing technology and high-density SNP markers to analyze the genetics of four main farming populations. A total of 109 individuals from four populations (NA, ZP, XL, and XC) were sequenced, identifying 5,384,029 high-quality SNPs. Results: The results showed that the nucleotide diversity (π) of each population ranged from 0.00155 to 0.00165 and observed heterozygosity (Ho) ranged from 0.253 to 0.282, which indicated low levels of genetic diversity. The results of the ROH analysis show significant inbreeding in the NA population. Genetic differentiation analysis revealed that the genetic differentiation among NA, XC, and ZP populations was relatively low (F_ST = 0.021–0.029). Conclusions: NA, XC, and ZP populations likely share a common origin of their fry stocks. Based on a phylogenetic tree, principal component analysis (PCA), and population structure analysis, the four populations were divided into four genetic groups. This study is the first analysis of the genetic diversity and population structure of P. teira farming populations in China, laying the foundation for the establishment of a base breeding population and the implementation of genetic improvement programs. Full article

Endometrial cancer is one of the most common malignancies of the female reproductive system, with incidence rising globally due to population ageing and life-style-related risk factors. Calcium (Ca²⁺) is a ubiquitous second messenger regulating diverse physiological processes, and its dysregulation has been increasingly implicated in carcinogenesis, including endometrial. Altered expression and function of Ca²⁺ channels, pumps, exchangers, and binding proteins disrupt the finely tuned balance of Ca²⁺ influx, efflux, and intracellular storage, leading to aberrant signalling that promotes tumour proliferation, migration, survival, and metastasis. This review summarises current knowledge on the molecular “Ca²⁺ toolkit” in the human uterus, highlighting the role of voltage-gated calcium channels (VGCCs), transient receptor potential (TRP) channels, store-operated calcium entry (SOCE) components, Na⁺/Ca²⁺ exchangers, purinergic receptors, P-type ATPases (SERCA, SPCA, PMCA), ryanodine (RyR) and inositol 1,4,5-trisphosphate (IP₃R) receptors, and mitochondrial Ca²⁺ uniporter (MCU) complexes in endometrial cancer progression. Multiple Ca²⁺-handling proteins, including CACNA1D, CACNA2D1, TRPV4, TRPV1, TRPM4, MCU, and RyR1, exhibit cancer-associated overexpression or functional changes, correlating with poor prognosis and aggressive disease features. Emerging evidence supports the therapeutic potential of targeting Ca²⁺ homeostasis using small-molecule inhibitors, ion channel modulators or gene-silencing strategies. These interventions may restore Ca²⁺ balance, induce apoptosis or autophagy, and suppress metastatic behaviour. While no clinical trials have yet explicitly focused on Ca²⁺ modulation in endometrial cancer, the diversity of dysregulated Ca²⁺ pathways offers a rich landscape for novel therapeutic strategies. Targeting key components of the Ca²⁺ signalling network holds promise for improving outcomes in endometrial cancer. Full article