Search Results (1,921)

The synergistic effect of using D2EHPA and TOPO together to enhance the extraction of samarium(III) from aqueous media via emulsion liquid membrane (ELM) technology was explored. D2EHPA in binary mixtures with TBP and in ternary mixtures with TOPO and TBP was also tested. Among the tested extractants, a binary mixture of 0.1% (w/w) D2EHPA and 0.025% (w/w) TOPO achieved 100% samarium(III) extraction at a low loading. This mixture outperformed D2EHPA-TBP and other systems because D2EHPA strongly binds to Sm(III) ions, while TOPO increases the solubility and transport efficiency of metal complexes. Additionally, process factors that optimize performance and minimize emulsion breakage were examined. Key insights for successfully implementing the process include the following: 5 min emulsification with 0.75% Span 80 in kerosene at pH 6.7 (natural), 250 rpm stirring, a 1:1 internal/membrane phase volume ratio, a 20:200 treatment ratio, and a 0.2 N HNO₃ stripping agent. These insights produced stable, fine droplets, enabling complete recovery and rapid carrier regeneration without emulsion breakdown. Extraction kinetics accelerate with temperature up to 35 °C but declined above this limit due to emulsion rupture. The activation energy was calculated to be 33.13 kJ/mol using pseudo-first-order rate constants. This suggests that the process is diffusion-controlled rather than chemically controlled. Performance decreases with Sm(III) feed concentrations greater than 200 mg/L and in high-salt matrices (Na₂SO₄ > NaCl > KNO₃). Integrating these parameters yields a scalable, low-loading ELM framework capable of achieving complete Sm(III) separation with minimal breakage. Full article

The fragile ecological environment of the Qinghai–Tibet Plateau (QTP) is significantly affected by human activities. This study employed a self-organizing map (SOM) for cluster analysis and positive matrix factorization (PMF) to trace the source of potentially toxic elements (PTEs) in the surface water of rivers. The results revealed that the average concentration of PTEs in the rivers was generally low. However, at some sampling points, especially in areas near the Qarhan Salt Lake, the content of Cu, Hg, and Ni were high. The water quality index (WQI), contamination factor (CF), and modified contamination index (mCd) identified good water quality, while potential Ni in the Quanji and Golmud River basins were the primary contaminants of concern. The potential ecological risk index (PERI) showed a low ecological risk. The SOM yielded four clusters of water PTEs, including Hg, Cu-Ni, Pb-Cd-Zn, and As. PMF model further revealed PTE sources, with industrial sources (39.73%) as the primary anthropogenic factor, followed by natural weathering (33.44%), vehicle emissions (21.52%), and atmospheric deposition (5.31%). This study laid the foundation for the ecological monitoring of rivers on the QTP and provided a reference for balancing industrial development and ecological protection in Qarhan Salt Lake areas. Full article

Extraction of metal ions from polluted waters and immobilization of metals in contaminated soils can be conducted using zeolites—porous aluminosilicate ion exchangers. The uptake of copper and zinc ions by the Georgian natural heulandite was studied under conditions of interaction of the zeolite with solutions (“liquid-phase” ion exchange) and powders (“solid-state” ion exchange) of the corresponding salts. The aim of the study was to compare the effect of the two procedures on the chemical composition and structure of the zeolite. It was found that the “liquid-phase” procedure provides a higher degree of uptake, particularly of zinc ions. Ion-exchange causes slight dealumination without decationization. Uptake of divalent ions occurs mainly through the leaching of sodium ions. According to X-ray data of ion-exchanged samples, the uptake of copper and zinc does not change the crystal structure of the zeolite framework, but nitrogen adsorption measurements show that ion exchange affects the mesoporous structure: solution treatment reduces the specific total pore volume and leads to the appearance of pores with a diameter of 4 nm. The “solid-state” procedure leads to an increase in specific total pore volume mainly due to an increase in the number of relatively small nanosized pores. Full article

Chloride-based deicing salt solutions have been contacted with concrete pastes containing slag cement at different conditions, such as slag replacement (20–80%), type (CaCl₂, MgCl₂, NaCl), and concentration (1 M–5 M) of the deicing salt, as well as temperature (ambient & −18 °C), and the extent of their reactions have been studied using XRD and ICP-OES. Also, solubility of Friedel salt (FS) has been measured in different types and concentrations of deicing salt solutions. It has been observed that the chemical deterioration arising from the formation and then dissolution of FS is more significant than the damage caused by the formation and expansion of oxychlorides in the pastes containing slag. While calcium oxychloride in its dried form can linger inside the paste for a long time, FS undergoes incongruent dissolution in CaCl₂ and MgCl₂ solutions and leaves the system. Presence of higher levels of AFm phases in pastes containing slag will further underscore this phenomenon. The extent of this chemical deterioration is relatively lower in NaCl solutions. Also, it was found that the nature of the chemical interaction changes with the concentration of the salt, as some disappeared phases might reappear and then disappear again. Using XRD and ICP-OES, this study provides a mechanistic understanding of salt-induced chemical deterioration in slag cement pastes by identifying phase-specific vulnerabilities and tracking the formation, transformation, and dissolution of key phases, such as Friedel’s salt and calcium oxychloride; additionally, the influence of various parameters have been studied, and chemical mechanisms have been proposed. Full article

The solid electrolyte interphase (SEI) is a passive layer, typically a few hundred angstroms thick, that forms on the electrode surface in the first few battery cycles when the electrode is in contact with the electrolyte in lithium-metal batteries. Composed of a combination of lithium salts and organic compounds, the SEI plays a critical role in battery performance, serving as a channel for Li-ion shuttling. Its structure typically comprises an inorganic component-rich sublayer near the electrode and an outer organic component-rich sublayer. Understanding heat transport through the SEI is crucial for improving battery pack safety, particularly since the Li-ion diffusion coefficient exhibits an exponential temperature dependence. This study employs first-principles calculations to investigate phonon-mediated temperature-dependent lattice thermal conductivity across the inorganic components of the SEI, including, LiF, Li₂O, Li₂S, Li₂CO₃, and LiOH. This study is also extended to the dependence of the grain size on thermal conductivity, considering the mosaic-structured nature of the SEI. Full article

In some cases, the catalytic processes involve the formation of self-organized supramolecular structures due to H-bonds and other non-covalent interactions. It has been suggested that the construction of self-assembled catalytic systems is a promising strategy to mimic enzyme catalysis at the model level. As a rule, the real catalysts are not the primary catalytic complexes, but rather, those that are formed during the catalytic process. In our earlier works, we have established that the effective catalysts M(II)_xL¹_y(L¹_ox)_z(L²)_n(H₂O)_m (M = Ni, Fe, L¹ = acac⁻, L² = activating electron-donating ligand) for the selective oxidation of ethylbenzene to α-phenyl ethyl hydroperoxide are the result of the transformation of primary (Ni(Fe)L¹)_x(L²)_y complexes during the oxidation of ethylbenzene. In addition, the mechanism of the transformation to active complexes is similar to the mechanism of action of NiFeARD (NiFe-acireductone dioxygenase). Based on kinetic and spectrophotometric data, we hypothesized that the high stability of effective catalytically active complexes may be associated with the formation of stable supramolecular structures due to intermolecular hydrogen bonds and possibly other non-covalent bonds. We confirmed this assumption using AFM. In this work, using AFM, we studied the possibility of forming supramolecular structures based on iron complexes with L²-crown ethers and quaternary ammonium salts, which are catalysts for the oxidation of ethylbenzene and are models of FeARD (Fe-acireductone dioxygenase). The formation of supramolecular structures based on complexes of natural Hemin with PhOH and L-histidine or Hemin with L-tyrosine and L-histidine, which are models of heme-dependent tyrosine hydroxylase and cytochrome P450-dependent monooxygenases (AFM method), may indicate the importance of outer-sphere regulatory interactions with the participation of Tyrosine and Histidine in the mechanism of action of these enzymes. Full article

The safe exploitation of marine natural gas hydrates, a promising cleaner energy resource, is hindered by reservoir instability during drilling. The inherent temperature–pressure sensitivity and cementation of hydrate-bearing sediments leads to severe operational risks, including borehole collapse, gas invasion, and even blowouts. This review synthesizes the complex instability mechanisms and evaluates the state of the art in inhibitive, wellbore-stabilizing drilling fluids. The analysis first deconstructs the multiphysics-coupled failure process, where drilling-induced disturbances trigger a cascade of thermodynamic decomposition, kinetic-driven gas release, and geomechanical strength degradation. Subsequently, current drilling fluid strategies are critically assessed. This includes evaluating the limitations of conventional thermodynamic inhibitors (salts, alcohols, and amines) and the advancing role of kinetic inhibitors and anti-agglomerants. Innovations in wellbore reinforcement using nanomaterials and functional polymers to counteract mechanical failure are also highlighted. Finally, a forward-looking perspective is proposed, emphasizing the need for multiscale predictive models that bridge molecular interactions with macroscopic behavior. Future research should prioritize the development of “smart”, multifunctional, and green drilling fluid materials, integrated with real-time monitoring and control systems. This integrated approach is essential for unlocking the potential of marine gas hydrates safely and efficiently. Full article

A theoretical study was performed using Density Functional Theory (DFT) to investigate the impact of π-conjugated aliphatic chain growth on the chemical and electronic properties of hybrid antimony pentachloride salts with pyridine- and imidazolium-based cations. Ten molecular systems were optimized to determine their ground-state geometry. Using conceptual DFT, parameters such as chemical hardness, electrophilicity index, electroaccepting power, and electrodonating power were studied. The energy gap was obtained for all ten molecular systems, ranging from −4.038 to −3.706 eV as the chain length increased, favoring intramolecular charge transfer in long-chain systems. Natural bond orbital (NBO) analysis showed charge redistribution between anion and cation as the π-conjugated aliphatic chain grows. At the same time, non-covalent interaction (NCI) studies revealed key attractions and repulsive interactions, such as H···Cl and Cl···π, which are modulated by chain length. These results demonstrate that the structural modification of the cation allows for the fine-tuning of the electronic properties of ionic liquids (ILs). Increasing the conjugated aliphatic chain length was observed to reduce the chemical hardness and electrophilicity index, as well as affecting the Egap of the molecular systems. This work demonstrates that there is an optimal size for the inorganic ion, allowing it to form an optimal IL compound. Full article

Urban tree planting on single-family-home lots represents a critical yet underexplored component of municipal greening strategies. This study examines residents’ perceptions of tree planting in Westpointe, a diverse neighborhood in Salt Lake City, Utah, as part of the city’s Reimagine Nature Public Lands Master Plan development effort. Through a mixed-methods approach combining qualitative interviews (n = 24) and a tree signup initiative extended to 86 residents, with 51 participating, this research explores the complex interplay of demographic, economic, social, and infrastructure factors influencing residents’ willingness to plant trees on single-family-home lots. The findings reveal significant variations based on gender, with women expressing more positive environmental and aesthetic motivations, while men focused on practical concerns including maintenance and property damage. Age emerged as another critical factor, with older adults (65+) expressing concerns about long-term maintenance capabilities, while younger families (25–44) demonstrated future-oriented thinking about shade and property values. Property characteristics, particularly yard size, significantly influenced receptiveness, with owners of larger yards (>5000 sq ft) showing greater willingness compared to those with smaller properties, who cited space constraints. Additional barriers, i.e., maintenance, financial, and knowledge barriers, included irrigation costs, lack of horticultural knowledge, pest concerns, and proximity to underground utilities. Geographic analysis revealed that Spanish-speaking social networks were particularly effective in promoting tree planting. The study contributes to urban forestry literature by providing nuanced insights into single-family homeowners’ tree-planting decisions and offers targeted recommendations for municipal programs. These include gender-specific outreach strategies, age-appropriate support services, sliding-scale subsidy programs based on property size, and comprehensive education initiatives. The findings inform evidence-based approaches to increase urban canopy coverage through private property plantings, ultimately supporting climate resilience and environmental justice goals in diverse urban neighborhoods. Full article

To achieve energy conservation, emission reduction, and green low-carbon goals for gas storage facilities, it is crucial to efficiently recover and utilize waste heat during gas injection while maintaining natural gas cooling rates. However, existing sensible and latent heat storage technologies cannot sustain long-term thermal storage or seasonal utilization of waste heat. Thermal chemical energy storage, with its high energy density and low thermal loss during prolonged storage, offers an effective solution for efficient recovery and long-term storage of waste heat in gas storage facilities. This study proposes a novel heat recovery method by combining a moving bed with mixed hydrated salts (CaCl₂·6H₂O and MgSO₄·7H₂O). By constructing both small-scale and full-scale three-dimensional models in Fluent, which couple the desorption and endothermic processes of hydrated salts, the study analyzes the temperature and flow fields within the moving bed during heat exchange, thereby verifying the feasibility of this approach. Furthermore, the effects of key parameters, including the inlet temperatures of hydrated salt particles and natural gas, flow velocity, and mass flow ratio on critical performance indicators such as the outlet temperatures of natural gas and hydrated salts, the overall heat transfer coefficient, the waste heat recovery efficiency, and the mass fraction of hydrated salt desorption are systematically investigated. The results indicate that in the small-scale model (1164 × 312 × 49 mm) the outlet temperatures of natural gas and mixed hydrated salts are 79.8 °C and 49.3 °C, respectively, with a waste heat recovery efficiency of only 33.6%. This low recovery rate is primarily due to the insufficient residence time of high-velocity natural gas (10.5 m·s⁻¹) and hydrated salt particles (2 mm·s⁻¹) in the moving bed, which limits heat exchange efficiency. In contrast, the full-scale moving bed (3000 × 1500 × 90 mm) not only accounts for variations in natural gas inlet temperature during the three-stage compression process but also allows for optimized operational adjustments. These optimizations ensure a natural gas outlet temperature of 41.3 °C, a hydrated salt outlet temperature of 82.5 °C, a significantly improved waste heat recovery efficiency of 94.2%, and a hydrated salt desorption mass fraction of 69.2%. This configuration enhances the safety of the gas injection system while maximizing both natural gas waste heat recovery and the efficient utilization of mixed hydrated salts. These findings provide essential theoretical guidance and data support for the effective recovery and seasonal utilization of waste heat in gas storage reservoirs. Full article

This study investigates key factors affecting the adsorption behavior of proteins on the multimodal chromatographic adsorbent Capto MMC, aiming to enhance selective protein separation strategies. Batch equilibrium experiments were conducted using six model proteins to explore the combined effects of pH, ionic strength, and the nature of salts (kosmotropic and chaotropic) on protein–ligand interactions. Given that the Capto MMC ligand supports multiple interaction modes beyond cation exchange, particular focus was placed on acidic proteins (pI 4–5), which exhibited binding even at moderately elevated pH values—conditions ineffective for conventional cation exchangers. Hydrophobic interactions were identified as critical for stable binding of proteins like BSA and fetuin, while hydrophilic proteins such as ovalbumin showed minimal adsorption. Chromatographic column experiments were performed to evaluate elution performance under various buffer conditions, revealing that prolonged adsorption phases can reduce recovery yields for proteins with less stable tertiary structures. The findings highlight how salt type, pH, and protein hydrophobicity interplay to modulate multimodal binding mechanisms, providing practical insights for the design of tailored purification protocols. Full article

Particulate matter (PM), a complex mixture of solid particles and liquid droplets, originates from both natural sources, such as sand, pollen, and marine salts, and anthropogenic activities, including vehicle emissions and industrial processes. While PM itself is not inherently toxic in all its forms, it often acts as a carrier of xenobiotic toxicants, such as heavy metals and organic pollutants, which adhere to its surface. This combination can result in synergistic toxic effects, significantly enhancing the potential harm to biological systems. Due to its small size and composition, PM can penetrate deep into the respiratory tract, acting as a physical “shuttle” that facilitates the distribution and bioavailability of toxic substances to distant organs. The omnipresence of PM in the environment leads to unavoidable and constant exposure, contributing to increased morbidity and mortality rates, particularly among vulnerable populations like the elderly, children, and individuals with pre-existing health conditions. This exposure also imposes a substantial financial burden on healthcare systems, as treating PM-related illnesses requires significant medical resources and leads to higher healthcare costs. Addressing these challenges necessitates effective mitigation strategies, including reducing PM exposure, improving air quality, and exploring novel approaches such as AI-based exposure prediction and nutritional interventions to protect public health and minimize the adverse effects of PM pollution. Full article

As an important tangible carrier of historical and cultural heritage, ancient city walls embody the historical memory of urban development and serve as evidence of engineering evolution. However, due to prolonged exposure to complex natural environments and human activities, they are highly susceptible to various types of defects, such as cracks, missing bricks, salt crystallization, and vegetation erosion. To enhance the capability of cultural heritage conservation, this paper focuses on the ancient city wall of Jingzhou and proposes a multi-stage defect-detection framework based on computer vision technology. The proposed system establishes a processing pipeline that includes image processing, 2D defect detection, depth estimation, and 3D reconstruction. On the processing end, the Restormer and SG-LLIE models are introduced for image deblurring and illumination enhancement, respectively, improving the quality of wall images. The system incorporates the LFS-GAN model to augment defect samples. On the detection end, YOLOv12 is used as the 2D recognition network to detect common defects based on the generated samples. A depth estimation module is employed to assist in the verification of ancient wall defects. Finally, a Gaussian Splatting point-cloud reconstruction method is used to achieve a 3D visual representation of the defects. Experimental results show that the proposed system effectively detects multiple types of defects in ancient city walls, providing both a theoretical foundation and technical support for the intelligent monitoring of cultural heritage. Full article

Hericium coralloides is a highly valued gourmet and medicinal species with growing market demand across East Asia, though industrial production remains limited by cultivation challenges. This study investigated the molecular characteristics, biological traits, domestication potential, and cultivation protocols of Hericium coralloides strains collected from the Changbaishan Nature Reserve (Jiling, China). Optimal conditions for mycelial growth included mannose as the preferred carbon source, peptone as the nitrogen source, 30 °C incubation temperature, pH 5.5, and magnesium sulfate as the essential inorganic salt. The fruiting bodies had a protein content of 2.43% g/100 g (fresh sample meter). Total amino acids comprised 53.3% of the total amino acid profile, while essential amino acids accounted for 114.11% relative to non-essential amino acids, indicating high nutritional value. Under optimized domestication conditions—70% hardwood chips, 20% cottonseed hulls, 8% bran, 1% malic acid, and 1% gypsum—bags reached full colonization in 28 days, with a 15-day maturation phase and initial fruiting occurring after 12–14 days. The interval between flushes was 10–12 days. The average yield reached 318.65 ± 31.74 g per bag, with a biological conversion rate of 63.73%. These findings demonstrate that Hericium coralloides possesses significant potential for edible and commercial applications. This study provides a robust theoretical foundation and resource reference for its artificial cultivation, supporting its broader industrial and economic utilization. Full article

Basalt-fiber-reinforced polymer (BFRP) composites, utilizing a natural high-performance inorganic fiber, exhibit excellent weathering resistance, including tolerance to high and low temperatures, salt fog, and acid/alkali corrosion. They also possess superior mechanical properties such as high strength and modulus, making them widely applicable in aerospace and shipbuilding. This study experimentally investigated the mechanical properties of BFRP plates under various strain rates (10⁻⁴ s⁻¹ to 10³ s⁻¹) and directions using an electronic universal testing machine and a split Hopkinson pressure bar (SHPB).The results demonstrate significant strain rate dependency and pronounced anisotropy. Based on experimental data, relationships linking the strength of BFRP composites in different directions to strain rate were established. These relationships effectively predict mechanical properties within the tested strain rate range, providing reliable data for numerical simulations and valuable support for structural design and engineering applications. The developed strain rate relationships were successfully validated through finite element simulations of low-velocity impact. Full article