Search Results (264)

Groundwater wells are essential for sustaining biodiversity in arid and hyper-arid regions. Wells are easily affected by external disturbances, particularly in hyper-arid regions like the Siwa Oasis, where the environmental variables influencing groundwater communities remain understudied. This study assessed the quality of several groundwater wells and agricultural drains based on the physical, chemical and hydrochemical parameters. The results classified the wells and drains into three distinct groups: (1) highly mineralized, carbonated systems with high concentrations of potassium, calcium, sodium, magnesium, chloride, and sulfate, and an average electrical conductivity (EC) of 12.01 mS/cm; (2) low-mineralized wells with an average EC of 2.15 mS/cm; and (3) a moderate one averaging 7.77 mS/cm. The major ions were dominated by Na⁺ (59.3%) and Mg²⁺ (26.8%) for cations, and Cl⁻ (79.1%) and SO₄²⁻ (13.4%) for anions in meq/L. Collectively, the evaluation based on total dissolved solids (TDS), sodium percentage (Na%), sodium adsorption ratio (SAR), and the US Salinity Laboratory (USSL) diagram revealed that about 80% of the analyzed wells are unsuitable for irrigation, with only three wells (W03, W12, and W16) deemed suitable for drinking. These findings confirmed a critical vulnerability of the oasis ecosystem. The uncontrolled and extensive use of finite, non-renewable aquifers for agricultural and other purposes is directly exacerbating water salinization and soil sodicity, posing a threat to the future sustainability of the oasis’s water resources. Full article

This study investigates the effect of added sodium sulfate on the performance of high-volume slag-cement mortar (HVSCM). Herein, Na₂SO₄ (0, 1, 2, and 4 wt.% Na₂O) was used to modify HVSCM. The compressive strength, fracture properties, microstructure, and environmental impact of the synthesized samples were analyzed. The results showed that the 1 day compressive strength of HVSCM can be improved by 345.5% with the addition of 4% Na₂O (as Na₂SO₄), compared to samples without Na₂SO₄. However, the 28 day compressive strength of Na₂SO₄-activated HVSCM was 14.3–26.4% lower than that of the non-activated HVSCM, though still comparable to OPC. Regarding fracture properties, the initial fracture toughness of non-activated HVSCM was 45.6% higher than that of Ordinary Portland cement (OPC) mortar. Furthermore, Na₂SO₄ activation further increased initial fracture toughness, with the sample containing 4% Na₂O showing a 101.1% improvement over OPC. In contrast, fracture energy was not significantly influenced by Na₂SO₄ addition. Microstructurally, the enhanced fracture properties of non-activated HVSCM were attributed to a higher degree of C-(A)-S-H polymerization and a denser binder phase. Sodium sulfate introduced sodium ions to strengthen electrostatic attraction and cohesion between C-(A)-S-H globules, offsetting reduced polymerization. Environmental assessment confirms that both activated and non-activated HVSCM substantially reduce embodied energy and CO₂ relative to OPC, while the additional embodied energy associated with Na₂SO₄ activation remains limited (<12%). Overall, this work provides a comprehensive understanding of the fracture behavior of Na₂SO₄-activated HVSCM, elucidating its capacity to enhance early-age strength and fracture toughness while highlighting its limited effect on long-term strength and fracture energy. These findings support the tailored use of Na₂SO₄ activation for sustainable construction applications. Full article

Black-odorous water pollution presents a serious threat to aquatic ecosystems and severely hinders the sustainable development of the ecological environment, as conventional remediation technologies often fall short in achieving the simultaneous removal of multiple pollutants. In this study, a novel composite remediation agent was developed by integrating microbial active components with modified clay minerals—sodium-modified zeolite (Na-Z) and magnesium–aluminum–lanthanum layered ternary hydroxides loaded onto sulfuric acid-modified bentonite (Mg-Al-La-LTHs@SBt)—through gel-embedding immobilization. This integrated system enabled the synergistic remediation of both overlying water and sediment pollutants. The modified clay minerals exhibited strong adsorption capacity for nitrogen and phosphorus compounds in the overlying water. Under 25 °C conditions, the composite agent achieved removal efficiencies of 58.14% for ammonium nitrogen (NH₄⁺-N) and 88.89% for total phosphorus (TP) while significantly reducing sedimentary organic matter and acid volatile sulfide (AVS). Notably, the agent retained substantial remediation efficacy even under low-temperature conditions (5 °C). High-throughput microbial community analysis revealed that the treatment enriched beneficial phyla (e.g., Proteobacteria) and beneficial genera (e.g., Thiobacillus) and suppressed sulfate-reducing groups (e.g., Desulfobacterota), promoting favorable nitrogen and sulfur transformations. These results provide a robust material and methodological basis for efficient, synergistic restoration of black-odorous water and the sustainable development of water resources. Full article

We investigated the roles and regulation of contractile and sodium ion transporter proteins in the pathogenesis of diarrhea in the acute ulcerative colitis. Acute ulcerative colitis was induced in male Sprague-Dawley rats using dextran sulfate sodium (DSS) in drinking water for seven days. The effects of nobiletin, a citrus flavonoid, were also examined. Increased myeloperoxidase activity, colon mass, and inflammatory cell infiltration were associated with damage to goblet cells and the epithelial cell lining indicating the development of acute ulcerative colitis. SERCA-2 calcium pump expression remained unchanged, whereas the phospholamban (PLN) regulatory peptide was reduced and its phosphorylated form (PLN-P) increased, suggesting a post-translational increase in SERCA-2 activity in the inflamed colon. Higher levels of IP3 were associated with a decrease in the Gαq protein levels without altering phospholipase C expression, suggesting that IP3 regulation is independent of Gαq protein signaling. In addition, the expression of sodium/hydrogen exchanger isoforms NHE-1, NHE-3 and carbonic anhydrase-1 and sodium pump activity were decreased in the inflamed colon. Nobiletin treatment of colitis selectively reversed the inflammatory and oxidative stress markers, including superoxide dismutase and catalase without restoring the expression of ion transporters. This study highlights alterations in the expression of ion transporters and their regulatory proteins in acute ulcerative colitis. These changes in the ion transporters are likely to reduce NaCl absorption and alter contractility, thereby contributing to the pathogenesis of diarrhea in the present model of acute ulcerative colitis. Nobiletin selectively ameliorates acute colitis in this model. Full article

In this study, the solvent displacement method was used. This is a low-energy technique that generates a spontaneous “oil-in-water” nanoemulsion by diffusing ethanol from the oily phase to the aqueous phase. Subsequently, chitosan, a biocompatible and biodegradable cationic polymer, was incorporated, applying ionic gelation with sodium sulfate (Na₂SO₄) to achieve uniform coatings. Atomic force microscopy (AFM) characterization revealed nanocapsules with defined morphology and regular topography. Analysis with WSxM 4.0 Beta 10 software revealed a partially ordered hexagonal arrangement, which was evidence of controlled synthesis and the potential of chitosan as a polymeric system. Full article

Myofibrillar protein (MP) aggregation in solutions with NaCl concentrations below 0.3 M results in poor solubility. Ultrasound-assisted glutaminase treatment (UGT) was applied to improve MP solubility in a low-salt solution (containing 0.1 M NaCl). The solubility increased with ultrasonic power and time, peaking at 44.34% (480 W, 15 min) and reaching 61% after UGT. Subsequently, the effect of post-sonication heat treatment (60 °C, 30 min) on the physicochemical and structural characteristics of ultrasound-enzyme treated MP (UEMP), prepared under specific ultrasonic conditions (480 W, 20 min), was systematically investigated. The findings revealed that UEMP exhibited higher hydrophobicity, sulfhydryl content, and turbidity, but reduced particle size, ζ-potential, and fluorescence, suggesting disulfide disruption and exposure of hydrophobic residues. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis revealed weakened high-molecular weight bands and intensified low-molecular weight bands. Fourier-transform infrared spectroscopy confirmed these structural rearrangements, with a blue-shifted amide A band and decreased amide I intensity. Heating further increased the hydrophobicity and fluorescence without altering the size, ζ-potential, or molecular weight. The red shift in the amide A band suggests reinforced local ordering. Rheology analysis showed non-Newtonian shear-thinning behavior, which was unchanged by UGT or heating. Collectively, UGT with moderate heating enhances MP solubility and thermal stability by disrupting stabilizing bonds and modulating the structure. Full article

Binder jet 3D printing of calcium sulfate-based materials combined with phase transformation offers a versatile route for fabricating customized bone grafts; however, controlling the transformation process remains a key challenge. This study investigates the effect of post-printing hydration in sodium chloride (NaCl) solutions on the phase transformation, dimension, and compressive properties of binder jet-printed calcium sulfate (3DPCaS) toward hydroxyapatite (3DPHA) formation. The as-printed 3DPCaS primarily consisted of bassanite with minor gypsum, which progressively transformed into gypsum upon immersion in NaCl solutions of varying concentrations (1–5 M) and durations (2–30 min). Increased immersion time and moderate NaCl concentrations (2–4 M) promoted gypsum formation without inducing dimensional instability. Subsequent transformation in phosphate solution produced 3DPHA with high hydroxyapatite (HA) purity, reaching 100% conversion. Microstructural analysis revealed recrystallized, plate-like gypsum crystals that served as favorable templates for HA nucleation. The resulting 3DPHA exhibited enhanced specific modulus (up to 274.9 MPa.m³/kg) and specific strength (up to 7.5 MPa.m³/kg). The optimal condition, immersion in 4 M NaCl solution for 30 min, achieved a balance between complete HA transformation, mechanical enhancement, and dimensional stability. Controlled ionic hydration thus represents a simple, low-cost, and effective strategy for improving properties of 3DPHA bone grafts. Full article

In arid regions, the soil degradation from salinization, low organic matter content, and compaction severely limits agricultural productivity. Leguminous perennials such as alfalfa (Medicago sativa L.) have the potential to restore soil quality, but their long-term effects remain underexplored in North African drylands. This study aimed to evaluate the impacts of long-term (7–8 years) alfalfa cultivation on soil fertility and salinity in the Ziban region of Algeria. Ninety topsoil samples (0–30 cm) from cultivated and adjacent uncultivated plots were collected and analyzed, determining organic matter (OM), soil organic carbon (SOC), soil nitrogen stock (SNS), electrical conductivity (EC), sodium adsorption ratio (SAR), pH, major cations (Ca²⁺, Mg²⁺, Na⁺), sulfate (SO₄²⁻), bulk density (BD), and texture. Compared with uncultivated soils, alfalfa cultivation increased OM by 82.26%, SOC by 78.38%, and SNS by 102.99%, while reducing EC by 40.36%, SAR by 28.94% and BD by 6.16% (p < 0.05), indicating significant improvements in fertility, structure and reductions in sodicity. PCA revealed distinct gradients separating fertility–salinity parameters from compaction–sodicity in cultivated and uncultivated soils. These results confirm that alfalfa systems enhance nutrient cycling, reduce salt stress, and improve structural stability in arid agroecosystems through reduced bulk density and increased organic matter in arid agroecosystems. Integrating alfalfa into land management strategies could promote sustainable restoration of degraded soils in drylands. Further research should optimize irrigation and organic inputs to maximize these benefits under climate-stress conditions. Full article

Objectives: Surfactants are commonly incorporated into amorphous solid dispersions (ASDs) to improve manufacturing and enhance the dissolution of poorly water-soluble drugs. However, their impact on in vitro dissolution, in vivo bioavailability, and in vitro-in vivo correlation (IVIVC) remains poorly understood, impeding the rational design of ASDs. This study aimed to elucidate the impact of six surfactants: anionic sodium lauroyl glutamate (SLG), sodium taurocholate (NaTC), sodium lauryl sulfate (SLS), and non-ionic polysorbate 80 (TW80), poloxamer 188 (P188), and polyoxyethylene lauryl ether (Brij-35), on the performance of paclitaxel (PTX)/HPMC-AS ASD. Methods: Binary PTX/HPMC-AS and ternary PTX/HPMC-AS/surfactant ASDs were prepared via rotary evaporation for FT-IR study. For dissolution and pharmacokinetic studies, low drug-loading formulations were prepared by physically blending PTX/HPMC-AS ASD with surfactants. Drug–polymer–surfactant interactions were investigated using NMR and FT-IR techniques. Dissolution performance was systematically evaluated by analyzing: (1) solubility of crystalline PTX in HPMC-AS/surfactant solutions; (2) supersaturation sustaining capacity in HPMC-AS/surfactant solutions; (3) surfactant effects on ASD dissolution and supersaturation generation; and (4) phase transformation during ASD dissolution. In vivo bioavailability was assessed in rats. Results: Findings revealed surfactant-specific effects: (1) SLG and P188 minimally affected bioavailability of PTX/HPMC-AS ASD (p > 0.05), consistent with their negligible effect on dissolution, attributable to incompatibility with PTX/HPMC-AS and weak molecular interactions; (2) TW80 significantly reduced bioavailability (p < 0.001) by inducing crystallization; thereby diminishing the amorphous advantage; (3) NaTC, Brij-35, and SLS markedly increased bioavailability (p < 0.001), owing to their compatibility with PTX and HPMC-AS, which enhanced dissolution and maintained amorphous state of precipitates. Surfactants appear to modulate ASD performance by governing supersaturation generation in solution and maintaining amorphous stability in the undissolved solid. Conclusions: The dissolution and bioavailability of ASDs are fundamentally controlled by compatibility between drug, polymer, and surfactant. Surfactant selection critically impacts ASD bioavailability. Comprehensive dissolution characterization, including supersaturation kinetics and precipitate phase analysis, enables prediction of bioavailability. Integrating molecular-level interaction analysis with multidimensional dissolution profiling is therefore essential for rational ASD design. Full article

Sulfonated carbon catalysts, as a type of solid protonic acid, have been widely recommended for various applications. However, syntheses of them typically require strict conditions, posing challenges in efficiency and environmental impact. Herein, we report a rapid, acid-free method to introduce sulfonic and sulfate ester groups onto carbon nanotubes (CNTs) by simply stirring them in an aqueous sodium persulfate solution (Na₂S₂O₈) at room temperature. Within 45 min, the treated CNTs reached sulfur-containing acid densities up to 0.34 mmol g⁻¹ without thermal treatment and hazardous reagents. The resulting catalyst demonstrated effective performance in terms of cellulose hydrolysis, attaining 31.6% conversion and 23.2% glucose yield. The process requires only the energy input of magnetic stirring, underscoring its environmental and practical advantages. This simple approach provides a sustainable and cost-effective alternative for the preparation of carbon-based catalysts, offering significant potential for biomass conversion and other green-chemistry applications. Full article

Seawater desalination has emerged as a crucial solution for addressing global freshwater scarcity. However, it generates significant volumes of concentrated brine waste. This brine is rich in dissolved salts and minerals, primarily, chloride (55%), sodium (30%), sulfate (8%), magnesium (4%), calcium (1%), potassium (1%), bicarbonate (0.4%), and bromide (0.2%), which are often discharged into marine environments, posing ecological challenges. This study presents a comprehensive global review of innovative technologies for recovering these constituents as valuable products, thereby enhancing the sustainability and economic viability of desalination. The paper evaluates a range of proven and emerging recovery methods, including membrane separation, nanofiltration, electrodialysis, thermal crystallization, solar evaporation, chemical precipitation, and electrochemical extraction. Each technique is analyzed for its effectiveness in isolating salts (NaCl, KCl, and CaSO₄) and minerals (Mg(OH)₂ and Br₂), with a discussion of process-specific constraints, recovery efficiencies, and product purities. Furthermore, the study incorporates a detailed techno-economic assessment, highlighting revenue potential, capital and operational expenditures, and breakeven timelines. Simulated case studies of a 100,000 m³/day seawater reverse osmosis (SWRO) facility demonstrates that a sequential brine recovery process and associated energy balances, supported by pilot-scale data from ongoing global initiatives, can achieve over 90% total salt recovery while producing marketable products such as NaCl, Mg(OH)₂, and Br₂. The estimated revenue from recovered materials ranges between USD 4.5 and 6.8 million per year, offsetting 65–90% of annual desalination operating costs. The analysis indicates a payback period of 3–5 years, depending on recovery efficiency and product pricing, underscoring the economic viability of large-scale brine valorization alongside its environmental benefits. By transforming waste brine into a source of commercial commodities, desalination facilities can move toward circular economy models and achieve greater sustainability. A practical integration framework is proposed for both new and existing SWRO plants, with a focus on aligning with the principles of a circular economy. By transforming waste brine into a resource stream for commercial products, desalination facilities can reduce environmental discharge and generate additional revenue. The study concludes with actionable recommendations and insights to guide policymakers, engineers, and investors in advancing brine mining toward full-scale implementation. Full article

Natural deep eutectic solvents (NaDES) represent novel biodegradable green extraction solvents obtained from natural metabolites such as sugars and organic acids. NaDES-based extracts have demonstrated better performance in in vitro assays compared to those obtained using conventional solvents. In this study, extracts of bilberry leaves (BL), bilberry fruits (BF), and green tea leaves (TL) were prepared using the following NaDES, respectively—malic acid + glycerol (MG), citric acid + sorbitol (CS), and tartaric acid + sorbitol (TS), whose formation was confirmed via FTIR spectroscopy. With the aim to evaluate the effect of gels loaded with NaDES extracts on skin biophysical parameters 2 h prior their application, as well as their anti-irritation potential against sodium lauryl sulfate–induced irritation, an in vivo study involving human volunteers was conducted. The results indicated that all extract-loaded gels exhibited notable anti-irritation potential, reducing artificially induced irritation and improving elevated skin parameters including transepidermal water loss (TEWL), erythema index (EI), and pH. The ΔTEWL at CS–BF site was 8.20 ± 0.34, while at TS–TL was 5.63 ± 0.30. The short-term efficacy study revealed increased skin hydration across all treated sites, preservation of skin pH within physiological limits, and reduction in EI at the site treated with TS–TL gel. Further in vivo studies are planned for confirming long-term skin effects. Full article

Pegmatite ores, the primary and technologically advanced lithium (Li)-bearing minerals, comprise various rare metal-based elements, including niobium (Nb), tantalum (Ta), tin (Sn), and beryllium. With increasing Li demand, global exploitation of pegmatite ores has generated vast tailings, mainly comprising quartz and feldspar. However, the process for comprehensively utilizing valuable minerals from pegmatite ores remains undeveloped, and the persistent gap between laboratory studies and industrial practice hinders the sustainable advancement of the pegmatite mineral processing industry. Herein, a comprehensive utilization beneficiation process was designed and validated at both laboratory- and pilot-scale levels. Locked-circuit flotation tests at the laboratory-scale on spodumene and feldspar yielded (i) an Li concentrate with an Li₂O grade of 5.80% and recovery of 88.62%, and (ii) a feldspar concentrate with a (K₂O + Na₂O) grade of 11.41% and good recoveries of K₂O (81.30%) and Na₂O (84.81%). In a 72 h continuous pilot-scale test, an Li flotation concentrate with an Li₂O grade of 5.72% and recovery of 86.78%, and a final Li concentrate with an Li₂O grade of 5.89% and recovery of 86.56% were obtained. Using Li flotation tailings as feed, a feldspar concentrate with a (K₂O + Na₂O) grade of 11.41% was obtained, achieving K₂O and Na₂O recoveries of >75%. The proposed process realizes nearly overall mineral recovery from the pegmatite ores, producing qualified concentrates of Li, Nb–Ta, Sn, feldspar, and quartz. In water reuse feasibility tests, ferrous sulfate (FeSO₄) was identified as the optimum flocculant at a dosage of 1000 g m⁻³. In the locked-circuit test with returned water, the consumption of sodium hydroxide (NaOH), sodium carbonate (Na₂CO₃), and EMT-12 (collector) was reduced by 18.75%, 3.33%, and 3.45%, respectively, while the flotation indices of the Li concentrate (Li₂O grade of 5.77% and recovery of 86.47%) were slightly lower than those in freshwater. In addition to increasing economic benefits, the process offers considerable reductions in tailings disposal, full utilization of multiple elements, and a potential decrease in water and reagent consumption. This study provides important guidelines for the mineral processing of Li pegmatite and other associated multimetallic ores. Full article

This study evaluated the performance of a constant-current two-compartment bipolar membrane electrodialysis (BMED) system comprising cation exchange membranes and bipolar membranes for the recovery of sodium hydroxide (NaOH) from sodium sulfate (Na₂SO₄) solution. Key operating parameters, current density, feed concentration, initial base concentration, and solution volume, were systematically varied to investigate their effects on ion transport, NaOH concentration, current efficiency, and energy consumption. At 450 A/m² with 1.30 M Na₂SO₄, 0.10 M initial NaOH, and 1.00 L solution volume, the system achieved a NaOH recovery yield of 69.21%, a final concentration of 2.13 M, a current efficiency of 36.39%, and an energy consumption of 1.82 kWh/kg Na₂SO₄ processed, corresponding to 4.72 kWh/kg NaOH produced, indicating optimal energy efficiency and process stability. To maximize concentration, the highest NaOH concentration of 2.85 M was obtained at the same current density by reducing the initial NaOH volume to 0.50 L, although this led to increased water transport and higher energy consumption (2.31 kWh/kg Na₂SO₄; 5.99 kWh/kg NaOH), compromising process efficiency. Full article

Aqueous zinc-ion batteries (ZIBs) have emerged as a promising candidate for large-scale energy storage due to their inherent safety, low cost, and environmental friendliness. However, manganese dioxide (MnO₂)-based cathodes, which are widely studied for ZIBs owing to their high theoretical capacity and low cost, face severe capacity fading issues that hinder the commercialization of ZIBs. This performance degradation mainly stems from the weak van der Waals forces between MnO₂ layers leading to structural collapse during repeated Zn²⁺ insertion and extraction; it is also exacerbated by irreversible Mn dissolution via Mn³⁺ disproportionation that depletes active materials, and further aggravated by dynamic electrolyte pH fluctuations promoting insulating zinc hydroxide sulfate (ZHS) formation to block ion diffusion channels. To address these interconnected challenges, in this study, a synergistic strategy was developed combining crystal engineering and pH buffer regulation. We synthesized three MnO₂ polymorphs (α-, δ-, γ-MnO₂), identified δ-MnO₂ with flower-like microspheres as optimal, and introduced sodium dihydrogen phosphate (NaH₂PO₄) as a pH buffer (stabilizing pH at 2.8 ± 0.2). The modified electrolyte improved δ-MnO₂ wettability (contact angle of 17.8° in NaH₂PO₄-modified electrolyte vs. 26.1° in base electrolyte) and reduced charge transfer resistance (Rct = 78.17 Ω), enabling the optimized cathode to retain 117.25 mAh g⁻¹ (82.16% retention) after 2500 cycles at 1 A g⁻¹. This work provides an effective strategy for stable MnO₂-based ZIBs, promoting their application in renewable energy storage. Full article