Search Results (1,141)

The strong adhesion between cathode materials and aluminium (Al) foil substrates presents a significant challenge in the recycling of spent lithium-ion batteries (LiBs). Conventionally, high temperatures and high concentrations of costly organic solvents such as N-methyl-2-pyrrolidone (NMP), dimethylacetamide (DMAC), dimethylformamide (DMF), and dimethyl sulfoxide (DMSO) are used to enhance ultrasonication-based delamination. In this study, a novel, eco-efficient approach was demonstrated for delaminating cathode materials from Al foil using a low-concentration organic citric-acid-assisted low-power ultrasonic treatment coupled with a gentle, low-power-per-volume mechanical mixing system at room temperature. The separation mechanism was attributed to the structure disruption, possibly swelling, of the polyvinylidene fluoride (PVDF) binder using low-concentration citric acid and the cavitation effects induced by ultrasound. Key parameters influencing the delamination efficiency included the solvent type, temperature, ultrasonic power, and treatment duration. Under optimised conditions, citric acid was used as the sonication reagent, with a process temperature of 20 °C, 60 W ultrasonic power, and 80 min of ultrasonication; a delamination efficiency of approximately 92% was achieved. The recovered cathode materials exhibited low agglomeration, favouring subsequent leaching processes. This work proposes an environmentally friendly and effective method for cathode and Al foil recovery from spent LiBs, integrating manual dismantling, ultrasonic treatment, and material separation. Full article

Reliable detection of microplastics by surface-enhanced Raman scattering (SERS) is often hindered by poor particle–substrate contact and limited access to plasmonic hotspots on conventional planar substrates optimized for molecular adsorption. Here, we report a rapid microwave-assisted carbothermal shock strategy to fabricate silver nanoparticle-decorated electrospun carbon fibers (AgNPs@ECF) as a three-dimensional plasmonic platform tailored for solid microplastic sensing. Localized microwave-induced heating in a mixed ethanol–hexane system enables Ag nanoparticle nucleation and anchoring on conductive carbon fibers within 45 s, yielding a mechanically compliant, junction-rich architecture without chemical reductants or vacuum processing. The AgNPs@ECF composite was evaluated using morphologically weathered polystyrene (PS) and polyethylene terephthalate (PET) microplastics, along with size-controlled PS bead standards ranging from ~50 nm to 45 μm. Across these models, SERS response is governed primarily by particle–substrate contact geometry and near-field accessibility rather than polymer type. The strongest enhancement occurs in the sub-micrometer regime, where particles can engage multiple AgNP-decorated fiber junctions, while ultrasmall and large, smooth particles show reduced enhancement due to limited contact or rapid field decay. Spatially resolved Raman mapping and finite-difference time-domain simulations support a contact-dominated enhancement mechanism, revealing localized field confinement at particle–fiber interfaces. These results establish the design principles for three-dimensional SERS substrates targeting heterogeneous solid particulates, demonstrating that contact-accessible plasmonic architectures are critical for reliable microplastic detection under realistic solid-particle measurement conditions. Full article

Lipid-based delivery systems (LDS), including lipid nanoparticles (LNPs) and liposomes, have become indispensable tools in modern biomedicine owing to their biocompatibility, capacity to encapsulate diverse therapeutic agents, and potential for targeted delivery. Despite their clinical success, conventional batch-based manufacturing methods are hindered by variability, limited scalability, and complex processing steps, slowing their broader translation. Microfluidic technologies offer a transformative solution by enabling precise fluid handling, rapid mixing, and reproducible production of LDS with tunable physicochemical attributes such as particle size, lamellarity, and drug-loading efficiency. This review highlights advances in microfluidic design strategies, including hydrodynamic flow focusing, staggered herringbone mixers, and toroidal micromixers, and evaluates how critical parameters such as flow rate, solvent composition, and lipid concentration influence LDS performance. Furthermore, we discuss the application of microfluidics in drug delivery, nucleic acid therapeutics, and vaccine platforms, underscoring its role in improving scalability, quality control, and clinical translation. Finally, we examine current challenges, including throughput limitations and solvent handling, while outlining future directions for integrating emerging materials and additive manufacturing to optimize LDS fabrication. Collectively, microfluidic platforms provide a promising pathway for next-generation lipid nanomedicines with enhanced precision, reproducibility, and therapeutic efficacy. Full article

Rapid point of care assessment of pulmonary surfactant composition by measuring the lecithin/sphingomyelin (L/S) ratio could improve management of patients with neonatal respiratory distress syndrome (nRDS). Attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR) offers a practical route to making such measurements, but the influence of the sample solvent prior to drying on measurement repeatability is poorly understood. We compare films dried from dichloromethane (DCM) and water (AQ) solvents (DCM-dry route vs. AQ-dry route) by ATR-FTIR and show that spectra from the AQ-dry route increased the signal-to-noise ratio (SNR) of a representative (2920 cm⁻¹) absorption peak for the mixture from 20.13 to 128.20 and for human endotracheal aspirate (ETA) from 6.33 to 8.13. A mixed nested analysis of variance (ANOVA) showed that drying route accounted for 89.52% of mixture peak height variance and reduced percent relative standard deviation (%RSD) from 23.5% to 16.2%, corroborated by multivariate analysis for ETA. We further demonstrate that partial least squares regression (PLSR) models trained on AQ-dry mixture spectra predicted L/S (R² = 0.91; root mean square error (RMSE) = 0.31) with 95% prediction interval grey-zone interpretation around L/S = 2.2, complemented by a receiver operating characteristic area under the curve (ROC-AUC) of 0.978. Full article

Volatile organic compound (VOC) emissions from industrial parks are a crucial source of urban air pollution. This study assessed VOC emissions and their impact on secondary pollution from three key industries—packaging and printing, pharmaceutical manufacturing, and furniture manufacturing—in a typical industrial park in the Guanzhong region of China. The results revealed considerable variation in organized outlet VOC concentrations between the different industries, with the highest level observed in furniture manufacturing (3449.9 ± 437.6 µg/m³) and the lowest level discovered for pharmaceutical manufacturing (410.9 ± 205.5 μg/m³). The VOCs were mainly aromatics (40.7%) and alkanes (21.8%), with pentane, isopentane, xylene, and ethylbenzene the most abundant species. Although organized emissions (1151.6 t/y) constituted the primary source of emissions, fugitive emissions (358.1 t/y) remained a major contributor and primarily contributed aromatics and alkanes. Critically, reactivity-based assessment demonstrated that alkenes and aromatics were the principal contributors to the ozone formation potential (>80%). With regard to the secondary organic aerosol formation potential, aromatics were overwhelmingly dominant, accounting for approximately 87% of the total potential, with xylene and ethylbenzene in furniture manufacturing alone contributing 72.9%. The findings highlight the importance of prioritizing controls on highly reactive alkenes and aromatics. Fugitive emission management during storage, mixing, and curing stages should be enhanced and solvents should be substituted to effectively control VOC emissions in industrial parks. Full article

Volatile organic compounds (VOCs) are ubiquitous environmental pollutants, and mixed VOC exposure has been linked to systemic inflammation. However, evidence remains limited regarding source-oriented VOC exposure patterns and their associations with inflammatory biomarkers in the general population. Using data from 1812 Korean adults participating in the Korea National Health and Nutrition Examination Survey (KNHANES) from July 2020 to August 2021, we identified source-oriented urinary VOC exposure patterns through factor analysis, yielding combustion-dominant and solvent-dominant indices. Environmental relevance was evaluated using an airborne VOC index, and associations with white blood cell (WBC) count were examined using generalized linear models, including interaction analyses by smoking status (defined specifically as conventional cigarette users). Both urinary indices were significantly associated with the airborne VOC index (p < 0.05), supporting their environmental validity. In models without interaction terms, the solvent-dominant index was positively associated with WBC count (β = 0.091, p = 0.030), while the combustion-dominant index did not reach statistical significance (β = 0.107, p = 0.081). However, significant interactions by smoking were observed for both indices (p for interaction < 0.001). Among conventional smokers, higher exposure to both combustion-dominant β = 0.614, p < 0.001) and solvent-dominant β = 0.571, p < 0.001) patterns was significantly associated with increased WBC counts, whereas no such associations were found among non-smokers. These findings indicate that while VOC patterns impact systemic inflammation, the associations are significantly modified by cigarette smoking. Our results underscore the importance of source-oriented approaches and the explicit evaluation of effect modification when assessing the health impacts of mixed VOC exposure. Full article

Scale-up synthesis in doped semiconductor metal oxide plasmonic nanocrystal batch reaction dispersion mixture processes often leads to significant changes in rheological behavior and flow characteristics, especially when using high-viscosity organic media. In this study, the rheological and hydrodynamic properties during the scale-up of a nanocrystal dispersion system where oleyl alcohol was used as a reaction solution medium were investigated. The flow field in a mechanically stirred 4 L pilot reactor was numerically analyzed using ANSYS Fluent based on experimentally obtained viscosity and density data of oleyl alcohol. At 290 °C, coincident with the nucleation and growth of plasmonic-doped metal oxide nanocrystals, solvent viscosity decreases to a corresponding Reynolds number of 9.2 × 10⁵, indicating that the dramatic viscosity reduction in oleyl alcohol above synthetic temperature batch reaction conditions drives a sharp increase in Reynolds number into a strongly turbulent mixing regime at synthetically relevant temperatures. The simulation results revealed that the scale-up process induces notable variations in shear rate distribution, local turbulence intensity, and overall mixing efficiency. These findings suggest that understanding rheological transitions under scale-up conditions is essential for optimizing nanoparticle synthesis and dispersion uniformity in industrial applications. Full article

Developing molecular electrocatalysts with controllable and predictable properties remains a central challenge in hydrogen evolution reaction (HER) catalysis. Herein, four Sb(III) corrole complexes (1–4) bearing zero to three p-cyano-substituted meso-phenyl groups (-CN Ph) were synthesized to investigate the effect of electron-withdrawing substituents on their catalytic HER performance, in which complexes 2–4 are newly reported. All prepared complexes were well characterized via UV–vis, NMR, HRMS, and XPS. SEM–EDS and UV–vis analyses indicated their uniform dispersion and excellent stability under organic and neutral aqueous solvent electrolysis conditions. When using TsOH as the proton source in DMF, complex 4 exhibited the highest activity with a TOF of 42.19 s⁻¹ at an overpotential of 895 mV. In mixed aqueous–organic media, the Faradaic efficiency of complex 4 reached 85.5%. The HER activity increases with the increasing number of cyano groups, and this observation has been rationalized via DFT calculations, which indicates a ligand-centered reduction and supports a possible ECEC pathway for the HER. These results highlight that cyano functionalization can modulate the electronic properties of Sb(III) corroles, thereby enhancing HER performance. This is helpful for designing efficient Sb(III) corrole-based HER catalysts. Full article

The formation of recyclable polyethylene materials is significantly limited by traditional crosslinking methods, which involve solvent-heavy processes and permanent chemical bonds that cannot be undone. Herein, we report an environmentally friendly and scalable approach to construct a thermo-reversible polyethylene network (PE-g-DA) via solvent-free, one-step melt processing based on furan–maleimide Diels–Alder (D–A) dynamic covalent chemistry. Furan-functionalized polyethylene was dynamically crosslinked with bismaleimide during melt mixing, fully compatible with conventional polyolefin processing techniques. FTIR spectroscopy, temperature-dependent solubility, and differential scanning calorimetry collectively confirm the reversible formation and dissociation of D–A adducts, enabling thermal switching of the network structure. Equilibrium swelling experiments based on the Flory–Rehner model indicate that the crosslink density can be precisely controlled by varying the bismaleimide content. As a result, PE-g-DA exhibits significantly enhanced tensile strength while maintaining high ductility at moderate crosslink densities. Notably, the dynamic network allows efficient thermal reprocessing, with recycled samples retaining approximately 93% and 80% of their original tensile strength after the first and second reprocessing cycles, respectively. Moreover, intrinsic thermal self-healing behavior is directly visualized by scanning electron microscopy at 120 °C. This work demonstrates that combining dynamic Diels–Alder chemistry with solvent-free melt processing offers a practical and sustainable route to recyclable, reprocessable, and self-healable polyethylene materials with clear potential for large-scale industrial production. Full article

Elastane is ubiquitous in polyester-based textiles and complicates depolymerization-based recycling because it can undergo thermal degradation and chemical bond cleavage, consuming reagents and forming low-molecular by-products that may compromise monomer quality. Here, we investigate alkaline PET depolymerization of PET/elastane blends under an intentional base-competition scenario in a laboratory kneader. Pure PET (100/0) and PET/EL blends (95/5 and 85/15, wt/wt) were processed under quasi-solid-state conditions at 140 °C for 5 min using solid NaOH dosed at 2.1 mol per mol PET repeat unit and pelletized feedstocks to ensure scale-relevant mixing and reproducible chamber filling. Torque and bulk-temperature profiles were similar across compositions, and isolated terephthalic acid yields remained in a narrow corridor (68–71%), indicating that PET depolymerization is not measurably impaired by 5–15 wt% elastane within this reaction window. Differential scanning calorimetry of water-insoluble residues revealed pronounced changes in elastane-related thermal transitions, evidencing elastane modification during treatment. Targeted ¹H NMR screening of recovered TA against a 4,4′-methylenedianiline spiked reference showed no detectable co-isolated aromatic diamines. Overall, the study demonstrates robust monomer recovery from mixed PET/EL textiles under solid-NaOH, short-residence, solvent-lean processing, while identifying residue analytics as the key bottleneck for quantifying elastane fate and closing component balances. Full article

Background/Objectives: We conducted this study to develop a generic amiodarone tablet pharmaceutically equivalent to the reference drug. This development is crucial for securing a stable supply chain for this orphan drug, which currently faces domestic market instability. Amiodarone, a national essential medicine, often experiences unstable supply due to its limited profitability. Methods: To secure this stable supply chain, we employed a factorial design, utilizing a Quality by Design (QbD) approach, to create the most suitable formulation. Initially, we observed a limitation where the formulation exhibited a flowability of 25% based on the Carr’s Index, which exceeded the target of 20%. To address this challenge, we incorporated lactose monohydrate during the pre-mixing stage rather than the post-mixing stage. Subsequently, we identified the binder content and the amount of granulation solvent as Critical Material Attributes (CMAs), and we performed a Design of Experiments (DoE). Result: Based on these investigations, we determined that the optimal prescription utilizes 5.71% povidone K25 and 40 mg/T of purified water. The final formulation successfully achieved an excellent flowability of 15.8%. Furthermore, this formulation showed a dissolution and bioequivalence PK profile equivalent to the reference drug in pH 1.2, 4.0, and 6.8 buffer solutions, each containing 1% Tween 80. Conclusions: Ultimately, the developed formulation is anticipated to establish a stable domestic supply chain and concurrently reduce national healthcare costs. These research findings also establish the groundwork for future continuous manufacturing implementation. Full article

N-cinnamoyl anthranilic acids are synthesized in a single, eco-friendly step by condensing various cinnamic acids with free 2-aminobenzoic acid derivatives using the mixed carbonic anhydride method. Subsequently, converting the resulting N-cinnamoyl anthranilic acids into their corresponding mixed carbonic anhydrides rapidly and efficiently affords 2-styryl-benzo[d][1,3]oxazin-4-ones. The method employs green solvents, such as acetone and 2-methyltetrahydrofuran; does not require metal catalysts or reflux conditions; and yields the desired final products without chromatographic purification. Full article

Quaternary Ni-Zn-Mg-Al metallic mixed oxide (MMO) catalysts were synthesized by co-precipitation from layered double hydroxide precursors. The effect of varying Zn content on physicochemical properties and catalytic performance was evaluated. Mg-Al and ternary Ni-Mg-Al and Zn-Mg-Al catalysts were synthetized for comparative purposes. XRD, N₂ sorption, MP-AES, CO₂-TPD, NH₃-TPD, SEM, and EDS characterized the materials’ physicochemical properties. The tested reaction was the transesterification between glycerol and dimethyl carbonate to obtain glycerol carbonate to improve the biodiesel industry. The catalyst containing both Ni and Zn showed the highest glycerol conversion among the evaluated materials. This was related to the increased number and strength of surface basic and acid active sites. Specifically, a high density of strong basic sites and acid ones in the quaternary catalysts was required for the reaction mechanism. The catalyst with 20 at% of Zn (MMO-Ni₁₅Zn₂₀) achieved the highest glycerol carbonate yield (89.6%) under mild reaction conditions and was solvent-free. MMO-Ni₁₅Zn₂₀ catalytic performance was associated with its high total basicity and predominance of strong basic sites and a moderate amount of acid sites. The differences observed between catalytic performances suggest that these results depend on the influence of structural, textural, acid, and basic properties. Reuse tests of the MMO-Ni₁₅Zn₂₀ catalyst showed moderate stability, with a progressive decrease in activity due to the loss of strong basic sites and the formation of agglomerated regions. Nevertheless, MMO-Ni₁₅Zn₂₀ maintained a GC selectivity of 100% in the successive cycles. Full article

In this study, the plasticizing effect of a deep eutectic solvent (DES) on polylactic acid (PLA) films mixed with sumac extract (SE) was investigated. DES (ChCl-Lev), consisting of choline chloride (ChCl) and levunic acid (Lev), was used. Chemical analysis confirmed the synthesis of ChCl–Lev and demonstrated the effective integration of the ChCl–Lev and SE system into PLA films. Incorporation of ChCl–Lev into the film led to an approximately 76% increase in elongation at break. This increase continued at approximately 49% in the film with 1% SE (SE1_ChCl-Lev10) additive. Antioxidant activity increased with SE content, reaching ABTS and DPPH scavenging activities of 96% and 83% at 1% SE (SE1_ChCl-Lev10) and 98% and 91% at 10% SE (SE10_ChCl-Lev10). Furthermore, antibacterial activity increased significantly as SE concentration increased; the film containing 10% SE showed strong inhibition against Staphylococcus aureus at a rate of 96.95 ± 0.32, while the inhibition rate against Escherichia coli also increased to 26.68 ± 2.89, whereas no antibacterial activity was observed in pure PLA. Considering these findings, it is anticipated that films produced using an innovative strategy could be a potential candidate for packaging, active food contact materials, and biomedical applications. Full article

Tight oil reservoirs are widely recognized as a critical successor in global unconventional energy development and are generally characterized by distinct geological features, including fine pore throats, pronounced heterogeneity, and a high concentration of clay minerals (e.g., montmorillonite and mixed-layer illite/smectite). Severe hydration, swelling, and fines migration are readily induced during water injection or conventional water-based fluid operations, thereby resulting in irreversible impairment of reservoir permeability. Despite the excellent injectivity and capacity for viscosity reduction associated with CO₂ flooding, sweep efficiency is severely compromised by viscous fingering and gas channeling, which are induced by the inherent low viscosity of the gas. While CO₂ foam technology is widely acknowledged as a pivotal solution for addressing mobility control challenges, its implementation is hindered by a primary technical bottleneck: the incompatibility between traditional water-based foam systems and strongly water-sensitive reservoirs. A dual challenge comprising water injectivity constraints and gas channeling is presented by strongly water-sensitive tight oil reservoirs. To address these impediments, three emerging low-damage CO₂ foam systems are critically evaluated in this review. First, the synergistic mechanisms of novel quaternary ammonium salts and polymers in inhibiting clay hydration and enhancing foam stability within modified water-based systems are elucidated. Next, the physical isolation strategy of substituting the water phase with a non-aqueous phase (oil/organic solvent) in organic emulsion systems is analyzed, highlighting advantages in wettability alteration and the mitigation of water blocking. Finally, the prospect of waterless operations using CO₂-soluble foam systems—wherein supercritical CO₂ is utilized as a surfactant carrier to generate foam or viscosify fluids via in situ formation water—is discussed. It is revealed by comparative analysis that: (1) Modified water-based systems are identified as the most economically viable option for reservoirs with moderate water sensitivity, wherein cationic stabilizers are utilized to inhibit hydration; (2) Superior wettability alteration and the elimination of aqueous phase damage are provided by organic emulsion systems, rendering them ideal for ultra-sensitive, high-value reservoirs, despite higher solvent costs; (3) CO₂-soluble systems are recognized as the future direction for “waterless” flooding, specifically tailored for ultra-tight formations (<0.1 mD) where injectivity is critical. Current challenges, such as surfactant solubility, high-temperature stability, and cost control, are identified through a comparative analysis of these three systems with respect to structure-activity relationships, rheological properties, damage control capabilities, and economic feasibility. What is more, an outlook is provided on the molecular design of future environmentally sustainable, cost-effective CO₂-philic materials and smart injection strategies. Consequently, theoretical foundations and technical support are established for the efficient exploitation of strongly water-sensitive tight oil reservoirs. By bridging the gap between reservoir damage control and mobility enhancement, this study identifies viable strategies for enhanced oil recovery. Crucially, it supports carbon neutrality and sustainable energy targets via CCUS integration. Full article