Search Results (533)

Linde Type A (LTA) zeolite was synthesised from purified Angren kaolin (Uzbekistan) by a metakaolin route. Raw kaolin was beneficiated by dispersion–decantation to reduce iron, calcined at 700 °C, and crystallised in NaOH solution at 100 °C. Products were characterised by powder X-ray diffraction (PXRD), X-ray fluorescence (XRF), Raman spectroscopy, N₂ physisorption and thermal analysis (TGA/DTA). PXRD confirmed crystalline LTA as the major phase (cubic lattice parameter a = 24.68 ± 0.02 Å), with residual quartz from the precursor. XRF gave a near-ideal bulk composition (Si/Al = 1.07, Na/Al = 0.98), confirming sodium incorporation, and Raman corroborated minor quartz and anatase impurities. The very low N₂ uptake at −196 °C reflects the restricted access of the 4 Å LTA windows rather than an absence of microporosity. Thermogravimetric analysis showed a ~13 wt% loss of zeolitic water below 300 °C, consistent with substantial hydration of the LTA framework. Locally sourced Angren kaolin can thus be converted into crystalline LTA, establishing a viable regional feedstock for a framework whose potential for molecular-sieve and ion-exchange applications remains to be evaluated by dedicated adsorption measurements. Full article

This study analyzes the structural and magnetic properties of a new composite material with a lithium borate glass matrix loaded with electric arc furnace slag, with a composition of 50Li₂O-50B₂O₃-80 wt.% slag. The amorphous nature of the obtained glass is confirmed by X-ray diffraction analysis (XRD). Differential scanning calorimetry (DSC) indicates that the material has an extremely high thermal stability as evidenced by its high glass transition temperature which is due to the reinforcing role of the slag metallic oxides. Additionally, magnetic studies reveal a highly frustrated magnetic state in the disordered system. The significant addition of mixed-valence iron ions (Fe²⁺/Fe³⁺) in the slag forms antiferromagnetic interactions in the system. These factors result in the stabilization of the spin-glass-like state. The incorporation of slag within the lithium borate matrix is a promising route to valorize this industrial by-product and to develop new functional materials. Full article

The rapid increase in electric vehicles has increased the generation of spent lithium-ion batteries (LIBs) and the need for efficient lithium recovery technologies. This study compared two distinct sulfation roasting routes, using sodium sulfate (Na₂SO₄) at 750 °C and sulfuric acid (H₂SO₄) at 550 °C, applied to black mass derived from lithium iron phosphate (LFP) and lithium nickel manganese cobalt oxide (NCM) batteries. Metal extraction efficiencies were determined by inductively coupled plasma optical emission spectrometry, while reaction products were identified by X-ray diffraction analysis. Sulfation roasting using Na₂SO₄ resulted in low lithium recovery for both materials, with maximum extractions of 5.7% for LFP and 24.5% for NCM. In contrast, H₂SO₄-assisted roasting achieved high lithium recovery from NCM black mass, reaching 90.8%, 91.5%, and 88.5% at 45, 90, and 180 min at 550 °C, respectively, with lithium predominantly converted into water-soluble lithium sulfate. Lithium extraction from LFP black mass remained below 13% under all conditions. Statistical analysis confirmed that lithium recovery at 45 min was equivalent to longer residence times, while prolonged roasting increased manganese coextraction and altered cobalt and nickel behavior. Overall, sulfuric acid-assisted sulfation roasting is an efficient and energy-favorable route for lithium recovery from NCM black mass, whereas sulfation roasting is unsuitable for LFP materials, under the tested conditions. The results highlight the importance of cathode chemistry segregation and demonstrate the feasibility of reducing processing time without compromising lithium recovery. Full article

In this study, a series of xFe₂O₃–Na₂O–CaO–SiO₂ glass-ceramics containing 0–28 wt.% Fe₂O₃ were prepared via the conventional melt-quenching technique. The resulting samples, designated S1–S4, were subsequently subjected to thermal treatment and investigated with respect to their structural, thermal, and optical characteristics. Differential scanning calorimetry analysis revealed the influence of the Fe₂O₃ concentration on the glass transition temperature and crystallization behavior of the samples. Structural analysis of the samples revealed that crystalline silicate and iron oxide phases constituted the predominant crystalline phases, with their overall crystallinity being strongly dependent on the Fe₂O₃ content and thermal treatment. Fourier transform infrared spectroscopy evidenced structural modifications of the silicate network induced by iron incorporation, while ultraviolet–visible–near infrared spectroscopy highlighted the presence of Fe²⁺/Fe³⁺ ions and their associated electronic transitions. The results indicate that increasing the Fe₂O₃ content significantly affects the network structure, redox state, and thermal behavior of the glass-ceramic system, leading to enhanced absorption properties. Full article

Selenium (Se) is a beneficial element that enhances plant antioxidant capacity, improves fruit quality, and contributes to the biofortification of horticultural crops. However, information regarding its effects on mineral nutrient balance and antioxidant metabolism in pomegranate remains limited. This study investigated the effects of foliar selenium (Se) application on fruit yield, mineral nutrient balance, antioxidant metabolism, and fruit quality of pomegranate (Punica granatum L.) cv. ‘Malas Saveh’ during the 2022 and 2023 growing seasons under orchard conditions in Iran. Trees were treated with sodium selenate at different concentrations using a randomized complete block design. In 2022, Se was applied at 0, 2, 4, and 6 mg L⁻¹, while in 2023, based on the results of the first-year screening phase, the concentration range was expanded to 0, 6, 8, and 10 mg L⁻¹ to further investigate plant responses to higher Se levels. Foliar Se application significantly increased fruit yield, fruit number, and Se accumulation in both leaves and fruits, confirming the effectiveness of Se biofortification. Selenium treatments also improved the nutritional composition of pomegranate fruits by increasing the concentrations of nitrogen (N), phosphorus (P), potassium (K), iron (Fe), and zinc (Zn), whereas manganese (Mn) concentrations declined, suggesting an antagonistic interaction between Se and Mn uptake. Significant improvements were observed in fruit quality traits, including soluble solids content, titratable acidity, vitamin C, total phenolics, anthocyanins, and antioxidant activity. The 6 mg L⁻¹ treatment in 2022 and the 8–10 mg L⁻¹ treatments in 2023 resulted in the most pronounced physiological and biochemical responses, with 10 mg L⁻¹ showing no further significant improvement for several key traits. Selenium application also enhanced the antioxidant defense system through increased activities of catalase (CAT), superoxide dismutase (SOD), peroxidase (POD), phenylalanine ammonia-lyase (PAL), and ascorbate peroxidase (APX), while reducing hydrogen peroxide (H₂O₂), malondialdehyde (MDA), and membrane ion leakage. Principal component analysis further confirmed the strong positive association between higher Se concentrations and improved mineral and biochemical characteristics. Overall, foliar Se application effectively enhanced pomegranate productivity, nutritional quality, antioxidant capacity, and physiological performance, highlighting its potential as a sustainable agronomic practice for the production of high-quality Se-enriched fruits. Full article

The Lion Man sculpture (UNESCO World heritage), a left mammoth tusk and mammoth ivory fragments from the excavations in the Hohlenstein-Stadel cave, Lone valley, Swabian Alb, Germany, were non-invasively analysed by means of external ion beam analysis (IBA) at the microfocus beamline at the particle accelerator AGLAE. The Lion Man was reconstructed from about three hundred mammoth ivory fragments, while the tusk is a separate find, and the fragments are individual pieces that could not be placed in the Lion Man. A characteristic trace element fingerprint, based on zinc, bromine and strontium contents, was established according to previous IBA studies of Aurignacian-era mammoth ivory and allowed for a comparison of the mammoth ivory objects. The specific Hohlenstein-Stadel cave trace element fingerprint could be distinguished from that of other Aurignacian sites in Europe but closely resembles that of the contemporary ivories from the neighbouring Hohle Fels cave. Although this study highlights that the Lion Man sculpture is chemically inhomogeneous due to diagenetic alterations, the left tusk and individual ivory fragments are chemically very similar to the Lion Man. However, further analyses are required to relate them to the same animal. Secondary minerals such as black manganese oxide dendrites and iron-rich aluminosilicates could be identified on the Lion Man and the other ivory objects at the surface. While dendrites are a characteristic diagenetic feature of mammoth ivory, the origin of iron-rich aluminosilicates can be linked either to sediment traces or surface treatment and use wear of the sculpture. Iron-rich zones are identified on particular parts of the Lion Man, namely, at the snout and at the left forearm with decorative signs. The snout is also particularly enriched in carbon, whose origin still needs to be clarified. Full article

The application of a huge number of lithium-ion batteries (LIBs) to electric vehicles has produced much solid waste. If not disposed properly, the solid waste may cause environmental pollution and is, per se, a waste of resources. Therefore, recycling valuable metals from LIBs is considered an ideal option for preventing environmental pollution and alleviating waste. Taking sulfuric acid (H₂SO₄) as the leaching agent and glucose (C₆H₁₂O₆) as the reducing agent, the ultrasonic-assisted reducing leaching was used to recycle lithium (Li) and iron (Fe) from spent lithium iron phosphate (LFP) batteries. Based on experimental results of conventional leaching, the research aimed to examine the influence of ultrasonic treatment on leaching rates of Li and Fe. Results show that the leaching rates of Li and Fe are separately 96.53% and 96.8% when the concentration of H₂SO₄ is 2 mol/L, the concentration of C₆H₁₂O₆ is 2 mol/L, the liquid–solid ratio is 15 mL/g, leaching temperature is 70 °C, leaching time is 60 min, and ultrasonic power is 100 W. Compared with conventional leaching, the leaching rates of Li and Fe separately increase by 10.84% and 12.33% through ultrasonic-assisted leaching under the same experimental conditions. Kinetics analysis of ultrasonic-assisted reducing leaching indicates that the activation energies of Li and Fe are 10.84 kJ/mol and 16.24 kJ/mol, respectively. The ultrasonic-assisted reducing leaching process of Li and Fe from LFP batteries is controlled by diffusion. Full article

Iron (Fe) contamination of water sources has become an increasing environmental concern, creating the need for effective, environmentally friendly, and cost-effective technologies for Fe(III) removal from aqueous systems. In the present work, the possibility of using the sulfuric acid-activated carbon made of Vigna trilobata rind waste for treating water contaminated with Fe ions was explored. The characteristics of the synthesized material were identified by physical, chemical, and spectroscopic methods, and its Fe ion sorption efficiency was studied experimentally in batch mode under various conditions. Equilibrium, kinetics, and thermodynamics of Fe ion removal by the prepared adsorbent were determined. The obtained adsorbent had a BET surface area of 20.55 m² g⁻¹ and showed high experimental adsorption capacity with the highest observed uptake of 19.81 mg g⁻¹. Based on the experimental results, the equilibrium data could be best described by the Langmuir equation (R² = 0.978). Kinetic analysis showed that the rate-limiting step in Fe ion sorption was intraparticle diffusion (R² = 0.921). Thermodynamic calculations indicated that the adsorption process occurred spontaneously (ΔG° = −4.31 to −6.53 kJ mol⁻¹) and endothermically (ΔH° = +7.11 kJ mol⁻¹). A comparative analysis showed that the sorption capacity of the studied adsorbent corresponded to that reported for the analogous materials produced from other biomasses. Full article

Composite hydrogel based on acrylic acid and acrylamide, modified with metal ions (Ni²⁺, Al³⁺, Fe²⁺, Fe³⁺) with concentration 0.3 wt%, were synthesized in water or polyethylene glycol (with a molecular weight of 400 Da) at three monomer ratios (7/3, 1/1, 3/7). Dynamic mechanical analysis shows that the equilibrium modulus of elasticity ($G_e$) of unmodified hydrogels increases with acrylamide content due to higher crosslinking density ($n_e$) and smaller cell size. ${AlCl}_3$ or ${NiCl}_2$ strengthen the structure ($G_e$ increases +53.5% in a 1/1 ratio), while iron salts cause softening (decreases to 90% when using ${FeC}_2{O}_4$). Partial replacement of polyethylene glycol reduces the elasticity but when using ${AlCl}_3$ happens synergistic increase $n_e$ 1.9 times in the ratio 3/7. The self-healing efficiency reaches ~100% for ${FeCl}_3$ in PEG gel in a ratio of 1/1 and 72.1% for ${Fe\left({NH}_4\right)}_2{\left({SO}_4\right)}_2$ hydrogel in 3/7. The electrical conductivity of hydrogels increases in the range of ${Al}^{3+}>{Ni}^{2+}>{Fe}^{3+}$, while matrix based on polyethylene glycol reduces the conductivity by an order of magnitude. For ${Ni}^{2+}$-containing samples, pinched hysteresis loops are observed in both water and polyethylene glycol. In contrast, ${Al}^{3+}$ causes rapid passivation in the water matrix, while in the matrix based on polyethylene glycol, the current–voltage characteristics follow ohmic behavior. The results demonstrate the possibility of directional regulation of the mechanical, electrical, and self-healing efficiency of hydrogels by selecting the ratio of monomers, the nature of the ion modifier, and the type of solvent. Full article

Metallic particle contaminants have been shown to have a detrimental effect on the reliability, performance and capacity of lithium-ion battery cells. In addition, they pose a significant safety risk. Typical contaminants, such as iron (Fe), copper (Cu) and aluminium (Al), often enter the cell via mechanical abrasion from production equipment, as burrs during electrode cutting, or through environmental exposure during handling. In such instances, the degradation mechanisms are known to accelerate, dendrite formation is increased, and, in the most unfavourable circumstances, thermal runaway is the likely outcome. Contaminants that do not affect cell behavior during formation and the initial cycles, yet only compromise safety at a subsequent stage, are of particular concern. Affected cells are known to pass end-of-line testing and make their way into the market as latent safety risks. Consequently, there is an urgent requirement for non-destructive diagnostic methods that are capable of identifying latent defects. The issue under discussion is approached in the present paper through the utilization of an innovative methodology that integrates the distribution of relaxation time (DRT) analysis of electrochemical impedance spectroscopy (EIS) data with machine learning techniques. The objective of this integrated approach is to facilitate the detection of critically contaminated pouch cells with a high degree of sensitivity. Full article

Hydroperoxides (R–OOH, organic hydroperoxides) constitute a relatively small but structurally diverse class of natural metabolites occurring in higher plants, fungi, and marine organisms. Their formation is closely associated with oxidative processes involving redox-active metal ions, particularly iron and copper, which promote reactive oxygen species (ROS) generation and the oxidative transformation of steroids and triterpenoids. In the present study, approximately 1500 naturally occurring steroids and triterpenoids were screened using the PASS (Prediction of Activity Spectra for Substances) platform to identify compounds with potential relevance to neurodegenerative disorders. Among the analyzed compounds, only 17 hydroperoxide-containing steroids and triterpenoids exhibited notable predicted anti-dementia activity and were selected for detailed evaluation. The selected compounds displayed a broad spectrum of predicted biological activities, including antineoplastic, anti-inflammatory, antiulcerative, antithrombotic, hepatoprotective, and neuroprotective effects. Several hydroperoxide-containing triterpenoids demonstrated particularly high predicted anti-dementia activity, with a norlupane-type hydroperoxide exhibiting the highest probability of activity (Pa = 0.972). The biological significance of these compounds may be related to the unique redox properties of the hydroperoxide functionality, which can participate in both oxidative and adaptive signaling processes. Because hydroperoxides interact with transition metal ions and reactive oxygen species, they occupy a complex position at the interface between oxidative stress, cellular defense mechanisms, and neurodegeneration. The present analysis highlights hydroperoxide-containing steroids and triterpenoids as an underexplored class of natural products with potential relevance to dementia research. However, the reported activities are based primarily on computational predictions and should be interpreted as indicators of pharmacological potential rather than experimentally validated therapeutic effects. Further investigations involving blood–brain barrier permeability assessment, biochemical studies, cellular assays, animal models, and clinical evaluation will be required to determine the true therapeutic value of these compounds in neurodegenerative diseases. Full article

Cadmium (Cd) is one of the most toxic heavy metals in the environment, and it severely represses photosynthesis, growth, development and nutrient uptake in photosynthetic organisms. Excessive cadmium (Cd) taken up by plants seriously threatens global food security and human health. Therefore, designing an eco-friendly and sustainable strategy that can reduce the accumulation of Cd in plants is a major challenge. Phosphorus (P), as an essential nutrient for plant growth, has been shown to play a pivotal role in mediating Cd-induced stress response. However, the molecular mechanisms underlying the crosstalk between phosphate signaling and Cd stress response remain largely uncharacterized, especially the role of the core phosphate homeostasis regulator Phosphate Starvation Response 1 (PSR1). Here, we used the model green microalga Chlamydomonas reinhardtii to investigate the physiological and transcriptomic responses to Cd stress in wild type (WT, CC-125) and PSR1 loss-of-function mutant (Crpsr1, CC-4267). Our results showed that the Crpsr1 mutant exhibited significantly enhanced Cd tolerance compared with WT under P-sufficient conditions, with a better growth phenotype and a significantly lower Cd accumulation. Transcriptome analysis revealed distinct gene expression profiles between WT and the Crpsr1 mutant in response to Cd treatment. Gene Ontology (GO) enrichment analysis showed that differentially expressed genes (DEGs) were mainly involved in primary metabolism, protein kinase activity, ion binding and transmembrane transport, which are critical processes for mitigating Cd stress. Notably, key genes associated with iron uptake and homeostasis were significantly upregulated in the Crpsr1 mutant under Cd stress, indicating a potential regulatory link between PSR1, iron homeostasis and Cd tolerance. Taken together, our findings establish a functional association between the central phosphate signaling regulator PSR1 and Cd stress response in green microalgae, and provide novel candidate genes and regulatory networks for developing engineered microalgae with enhanced Cd phytoremediation capacity. Full article

Lithium-ion batteries (LIBs) release significant amounts of toxic, corrosive, and flammable gases when they enter thermal runaway (TR). These emissions can be hazardous to human health, damage nearby equipment, pose fire and explosion risks, and degrade air quality. This study measured concentrations for a range of hazardous gases released from TR-driven combustion of cylindrical lithium iron phosphate (LFP) and pouch-style lithium cobalt oxide (LCO) LIB cells. Gas emissions were measured by dedicated analyzers and Fourier transform infrared spectroscopic (FTIR) analysis, and emission factors were calculated. Dangerous concentrations of hydrogen fluoride (HF) were observed, reaching up to 50 ppm from the combustion of single LIB cells. Large amounts of combustible electrolyte solvents and light hydrocarbons were released in some cases, depending on cell combustion behavior. Electrolyte solvents, hydrogen chloride (HCl), and particles were released earlier than other species and should be targeted for early TR detection. Gas emissions were correlated with cell state of charge (SOC) and combustion behavior. Cells at high SOCs had higher peak concentrations of HF, HCl, CO, and flammable hydrocarbons, and these peaks happened sooner after cell failure than for low-SOC tests. Full article

The corrosion behavior and time-dependent mechanism of 22MnB5 steel featuring a thinned Al-Si coating (60 g/m²) were systematically investigated in a chloride ion wet–dry cyclic environment, motivated by the demand for thinning and toughening development of aluminum-silicon coatings. A periodic immersion accelerated corrosion test using 3.5% NaCl solution was conducted, together with macro/microscopic morphology observation (SEM/EDS), phase analysis (XRD, FTIR), and electrochemical measurements (polarization curves, EIS). The Al-Si coated steel was studied over corrosion periods of 1, 8, 10, and 20 days to elucidate its corrosion behavior, interfacial evolution, and failure mechanism. The results indicated that the corrosion process exhibited a three-stage evolution: stable protection, rapid failure, and dynamic equilibrium. At the initial stage (1 day), a dense Al₂O₃ passive film formed on the coating surface, providing excellent substrate protection, with a corrosion current density of only 1.77 µA/cm² and a maximum charge-transfer resistance (R₂) of 652 Ω·cm². In the middle stage (8 days), Cl⁻ permeated through the cracked film, triggering selective dissolution of Al, while Si was enriched in situ to form a porous residual layer; the corrosion current density (I_corr) sharply increased to 13.25 µA/cm², and R₂ dropped to its minimum of 156.6 Ω·cm². Corrosion products at this stage were mainly Al₂O₃ and SiO₂, accompanied by small amounts of iron oxyhydroxides and hydroxides, and local coating failure began to appear. During the later stage (10–20 days), the corrosion products evolved into γ-FeOOH, α-FeOOH, and Fe₂O₃, which, together with an amorphous SiO₂ gel network enriched at the interface, formed a dual-layer composite rust layer. R2 consequently recovered from 156.6 Ω·cm² at 8 days to 424 Ω·cm² at 20 days, indicating a reduced corrosion rate and entry into a stable inhibition stage. The critical failure mechanism is that Cl⁻ preferentially penetrates the surface of the Al₂O₃ passive film, disrupting the metastable state of the coating and thereby creating pathways for corrosive media intrusion. The findings of this study can provide technical support for the safe application of such as-received coatings in non-load-bearing components with heat and corrosion resistance requirements. Full article

The pancreas is an organ with two functions: endocrine and exocrine. The proper functioning of the pancreas depends on many factors. One of these is trace elements—precise control of trace element homeostasis is important for both the endocrine and exocrine parts. This review provides a comprehensive summary of current knowledge regarding the role of trace elements: iron (Fe), copper (Cu), cobalt (Co), iodine (I), manganese (Mn), zinc (Zn), silver (Ag), cadmium (Cd), mercury (Hg), lead (Pb), and selenium (Se) in pancreatic physiology and their influence on the pathogenesis of key diseases of this organ, such as diabetes (DM), acute (AP) and chronic pancreatitis (CP), autoimmune pancreatitis (AIP), and pancreatic cancer (PC). Trace elements, including Fe, Cu, Zn, Se, and Mn, play a fundamental role in maintaining endocrine and exocrine homeostasis, participating in insulin synthesis, stabilizing digestive enzymes, and the functioning of antioxidant systems. It has been demonstrated that disturbances in their concentrations lead to the activation of pathological molecular pathways, including oxidative stress, chronic inflammation, and beta-cell apoptosis. In the context of diabetes, excess Fe promotes ferroptosis, whilst exposure to heavy metals such as Cd, Pb, and Hg induces insulin resistance and pancreatic islet dysfunction. In the course of pancreatitis, elements such as Zn and Se exhibit protective potential by stabilizing tissue barriers, whereas toxic metals impair ion transport, exacerbating fibrotic processes. Furthermore, analysis of available data indicates a significant association between heavy metal accumulation and pancreatic carcinogenesis, driven by DNA damage and oncogene modulation. Understanding pancreatic metallomics opens new prospects for early diagnosis, environmental prevention, and the development of targeted therapeutic strategies that restore the body’s micronutrient balance. Full article