Search Results (783)

Betaine, a simple natural zwitterion, is currently attracting widespread attention. Although historically labeled as an osmoregulator in agriculture and a methyl donor in animal nutrition, the molecule is now being repositioned at the forefront of green chemistry and materials science due to its unique physicochemical structure. This review critically explores the expanding horizon of betaine applications, bridging the gap between its established biological functions and its emerging roles in recently reported technologies, such as deep eutectic solvents (DESs), cocrystal engineering, and sustainable polymer synthesis. Beyond summarizing its versatile functionality across biomedicine, food science, and industrial formulations, we provide a comprehensive bibliometric analysis to map the evolution of research trends, identifying a clear focus toward industrial ecology and advanced materials. By synthesizing current advancements and discussing potential future directions, this work highlights betaine not merely as a supplement, but as a versatile molecular component with potential applications in sustainable materials and chemical engineering processes. Full article

Understanding the mechanisms of microstructure evolution and defect formation, and their influence on mechanical properties and fracture mechanisms (from crack initiation to failure stage), is essential for manufacturing high-strength, fatigue-resistant A7075 alloy by selective laser melting (SLM). In this investigation, the A7075 alloy was fabricated using a laser power of 350 W with various hatch spacings of 1.0, 1.5, and 2.0 μm, and scanning speeds of 800, 1100, and 1300 mm/s. The results show that the alloy exhibits an equiaxed grain structure, which varies from coarse grains at small hatch spacing and low scanning speed to fine grains with increasing hatch spacing and scanning speed. The alloys exhibit low tensile strength due to solidification cracking and pores. However, this tensile strength increases with hatch spacing, while it decreases with scanning speed. At small hatch spacing and low scanning speed, fracture occurs through the coalescence of pores and solidification cracking along the weakly bonded grain boundaries (GBs) due to eutectic growth along these boundaries. In contrast, with increasing hatch spacing and scanning speed, fracture occurs through solidification cracking and coalescence of pores. This research provides valuable insights into the microstructure evolution, defect formation, and fracture mechanisms of the A7075 alloy under common processing conditions. Full article

This study systematically investigates the microstructural characteristics and mechanical properties of resistance spot-welded joints in 3 mm thick non-heat-treatable die-cast AlSi₇MnMg alloy, with particular focus on the influence of element segregation and secondary phase behavior on fracture mechanisms and the process window. The results indicate that the weld nugget exhibits a typical dual structure consisting of columnar and equiaxed grain zones, with a corresponding “M”-shaped microhardness profile. Significant segregation of Si, Fe, and Mn elements at the nugget boundary was observed, leading to the formation of low-melting-point eutectic regions and secondary phase bands. These features induce microporosity along segregation trajectories, serving as crack initiation sites and resulting in a notably narrowed spot welding process window. From the perspective of microstructure and solute behavior during non-equilibrium solidification, this work elucidates the intrinsic mechanisms governing joint performance and process stability in non-heat-treatable die-cast aluminum alloys, providing a theoretical basis for their engineering applications. Full article

The sustainable conversion of agricultural waste biomass, particularly crop residues such as corn stover, into high-value products is vital for reducing their open-field burning and mitigating environmental hazards. The hydrothermal carbonization (HTC) process integrated with natural deep eutectic solvents (NADES) presents an alternative approach for valorizing biomass into lignin-rich solid fuels and fermentable sugars for bioethanol production. In this study, corn stover was subjected to HTC using deionized (DI) water, a xylose-based NADES (ChCl:Xy:W), and an oxalic acid-based NADES (ChCl:OA:W) in a 150–300 °C temperature range to optimize both solid fuel and sugar stream yields. Characterization, including fiber analysis, SEM, FTIR, EDS, and bomb calorimetry, was conducted to evaluate structural, compositional, and energetic transformations. The results explored the HTC process, restructuring the biomass, promoting extensive hemicellulose solubilization and cellulose depolymerization, as well as substantially enriching lignin and polymerized compounds with increasing temperature. In addition, the DI water at 300 °C generated a lignin-rich residue, the Xy-based NADES effectively removed ash and extractives, and the OA-based NADES produced the most carbon-dense hydrochar with the highest calorific value. Collectively, these findings demonstrate that solvent-assisted HTC may be employed as a possible strategy for the valorization of agricultural residues into high-energy solid fuels. Full article

Plant polyphenols are valuable secondary metabolites with significant bioactivities; however, their efficient extraction faces multiple challenges, including the structural complexity arising from their coexistence in free and bound forms within plant matrices, as well as their sensitivity to oxidation and heat. Although emerging green extraction technologies such as deep eutectic solvents, supercritical fluid extraction, and physical field enhancement show potential, current research largely remains method-oriented, lacking an in-depth understanding of the coupling mechanisms between molecular interactions and mass transfer processes. This review explicitly proposes a “mechanism-driven, synergistic integration” framework for the green extraction of plant polyphenols. By systematically analyzing the molecular basis of extractability and the complementarity among emerging technologies, this framework provides theoretical guidance and a practical blueprint for transitioning from empirical optimization to intelligent, synergistic system design. Specifically, it begins by systematically dissecting the structural characteristics of polyphenols and their interactions with cell wall components to clarify the molecular basis of extractability. Next, it critically reviews the mechanisms, advantages, and engineering bottlenecks of representative green technologies, with a focus on how synergistic integration strategies based on complementary mechanisms can overcome the limitations of single technologies to achieve higher extraction efficiency and selectivity. Furthermore, it evaluates the application of response surface methodology and artificial neural networks in process modeling. Finally, it highlights critical challenges such as industrial scale-up, sustainability assessment, and intelligent manufacturing. This review advocates a paradigm shift from optimizing single techniques toward designing intelligent, synergistic systems grounded in mechanistic insights. Full article

A series of chitosan-based films was obtained by combining the covalent crosslinking of chitosan with dialdehyde starch (DAS) and plasticization using a choline chloride–malonic acid deep eutectic solvent (DES), thereby engineering their structural, mechanical, and surface properties for advanced packaging applications. DAS was synthesized via periodate oxidation of potato starch and characterized by FTIR and quantification of aldehyde groups through acid–base titration, enabling precise control of the –NH₂ (chitosan) to –CHO (DAS) molar ratios (40:1, 20:1, 10:1) used for film formation. Chitosan films (neat, DAS-crosslinked, DES-plasticized, and DES-plasticized/DAS-crosslinked) were obtained by solution casting, with constant total chitosan and/or Ch+DES mass across formulations, and subsequently examined in terms of molecular structure, density, mechanical characteristics, micro- and nanoscale morphology, color, wettability, and surface free energy. The most significant changes relevant to potential applications were observed in mechanical properties and surface free energy. The incorporation of DAS and DES into chitosan resulted in a significant reduction in Young’s modulus from 1150 MPa to 130 MPa, accompanied by a significant increase in elongation at break—from 10% to almost 90%. Moreover, it should be noticed that the addition of DAS and DES led to a nearly twofold increase in surface free energy, from 32.5 to 59.9 mJ m⁻². While previous studies have predominantly focused on single modifications of chitosan—either covalent crosslinking with dialdehyde starch (DAS) or plasticization with deep eutectic solvents (DES)—this work introduces a pioneering dual-modification strategy that simultaneously integrates both techniques, representing the first systematic investigation of their synergistic effects unattainable through individual approaches. Full article

The relevance of this study is determined by the need for new technological solutions to enhance the productivity of wells producing heavy and highly viscous crude oil. The work investigates multicomponent Al–Ga–In–Sn alloys as reactive systems capable of generating heat and hydrogen upon contact with water. The focus is placed on optimizing melting parameters and assessing how alloy composition and structural features affect reactivity. Phase composition was analyzed by X-ray diffraction, microstructure by SEM-EDX, and elemental composition by XRF. The results show that the hydrogen generation rate and heat release depend on melting temperature, holding time, and ratios of activating metals, as well as the physicochemical properties of the formation water, particularly salinity and pH. Reaction enthalpy and conversion efficiency were quantified. The highest hydrogen output and thermal effect were observed for the following compositions—90 wt.% Al, 5 wt.% Ga, 2.5 wt.% In, 2.5 wt.% Sn; and 85 wt.% Al, 5 wt.% Ga, 5 wt.% In, 5 wt.% Sn (825 °C, 30 min). Rapid heat and gas release is attributed to the eutectic structure and micro-galvanic interaction, which eliminate the induction period. These findings demonstrate the potential of such alloys for in situ heating, enhanced oil recovery, and autonomous hydrogen-energy applications. Full article

Polyphenols are a structurally diverse group of plant secondary metabolites widely recognized for their antioxidant, anti-inflammatory, antimicrobial, and chemoprotective properties, which have stimulated their extensive use in food, pharmaceutical, nutraceutical, and cosmetic products. However, their chemical heterogeneity, wide polarity range, and strong interactions with plant matrices pose major challenges for efficient extraction, separation, and reliable analytical characterization. This review provides a critical overview of contemporary strategies for the extraction, separation, and identification of polyphenols from plant-derived matrices. Conventional extraction methods, including maceration, Soxhlet extraction, and percolation, are discussed alongside modern green technologies such as ultrasound-assisted extraction, microwave-assisted extraction, pressurized liquid extraction, and supercritical fluid extraction. Particular emphasis is placed on environmentally friendly solvents, including ethanol, natural deep eutectic solvents, and ionic liquids, as sustainable alternatives that improve extraction efficiency while reducing environmental impact. The review further highlights chromatographic separation approaches—partition, adsorption, ion-exchange, size-exclusion, and affinity chromatography—and underlines the importance of hyphenated analytical platforms (LC–MS, LC–MS/MS, and LC–NMR) for comprehensive polyphenol profiling. Key analytical challenges, including matrix effects, compound instability, and limited availability of reference standards, are addressed, together with perspectives on industrial implementation, quality control, and standardization. Full article

Traditional polysaccharide extraction suffers from low efficiency and high energy consumption, while deep eutectic solvents (DESs) are promising sustainable solvents. This study used DES ChCl-LA (1:2) with ultrasonic assistance to extract polysaccharides from red alga A.taxiformis. Optimized via single-factor experiments and response surface methodology (350 W, 1:30 g/mL, 75 °C), the yield reached 11.28% ± 0.50% (1.5 times higher than that obtained by water extraction). Structural characterization revealed that the DES extract was an acidic polysaccharide, mainly composed of galactose (89.2%), glucose (4.9%), xylose (4.9%), and glucuronic acid (1.0%), with a weight-average molecular weight of 99.88 kDa. Density functional theory and molecular dynamics simulations showed that ChCl-LA enhanced galactose solubility via stronger hydrogen bonding (−25.33 vs. −5.06 kcal/mol for water). Notably, the immunological activity of the DES-extracted polysaccharide was significantly compromised compared to the water-extracted counterpart (p < 0.05). At a concentration of 0.25 mg/mL, the water-extracted polysaccharide-treated group exhibited a 33.98% higher neutral red phagocytosis rate in macrophages, a nitric oxide (NO) secretion level of 34.14 μmol/L (94.98% higher) compared with the DES-extracted polysaccharide group, as well as significantly higher secretion levels of tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6). The observed disparity in bioactivity is likely due to the distinct chemical profiles resulting from the two extraction methods, including the significantly reduced molecular weight and potential alterations of sulfation degree, monosaccharide composition, and protein content in the DES-extracted polysaccharide. This mechanistic perspective is supported by the relevant literature on the structure–activity relationships of polysaccharides. This study demonstrates the potential of ChCl-LA and elucidates the complex effects of extraction methods on polysaccharide’s structure and function, thereby informing the high-value utilization of A. taxiformis in functional foods. Full article

In this study, a pectin polysaccharide named DESP was extracted using a deep eutectic solvent (DES) from sweet potato residue (SPR) and the extract was optimized through response surface methodology (RSM). The DESP, based on choline chloride–urea (ChCl-Ur), was characterized for yield, molecular weight (Mw), and monosaccharide composition. Fourier-transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), ¹H-nuclearmagnetic resonance (¹H-NMR), and scanning electron microscopy (SEM) were used to analyze the structure. Optimal extraction conditions for DESP were ChCl-Ur in a molar ratio of 1:2, water content of 75 wt.%, extraction time of 125.7 min, extraction temperature of 83.2 °C, and a liquid-to-solid ratio of 37.0 mL·g⁻¹. The optimized extraction yield was 5.6% ± 0.09%, which was 2.4 times higher than that of hot-water-extracted sweet potato pectin (HWSP, 2.32%). The monosaccharide analysis revealed that galacturonic acid (GalA) was the most abundant saccharide, followed by glucose (Glc), galactose (Gal), arabinose (Ara), and rhamnose (Rha). The Mw of DESP was 20.90 kDa, which was lower than that of HWSP and HASP. In addition, DESP exhibited certain anti-inflammatory activity. Full article

The microstructure and wear behaviors of Mg₂Si/Al composites with 0 wt.%, 5 wt.%, and 10 wt.% SiC particles were studied using XRD, OM observation, SEM observation, EDS analysis, an extraction experiment, a hardness test, and the dry sliding wear test. It is shown by the results that after the addition of 10 wt.% SiC particles, the population of primary Mg₂Si particles increased, while the mean size of these particles reduced from 40 ± 10 μm (in the SiC-free composite) to 25 ± 8 μm. Both the matrix and the eutectic structure were refined. The tetrakaidecahedral morphologies of Mg₂Si crystals were confirmed by the results of extraction tests. The wear test results with GCr15 steel as the friction pair show that the Mg₂Si/Al composite with 10 wt.% SiC particles displayed more favorable wear resistance than the specimens with 0 wt.% and 5 wt.% SiC particle additions under both constant load and constant sliding velocity conditions. Under applied loads of 10 N, 20 N, and 30 N at a fixed sliding speed of 300 r/min, the wear rate of the Mg₂Si-Al composites reinforced with 10 wt.% SiC particles was 36.01%, 48.29%, and 23.32% lower than that of the SiC-free composites, respectively. When the sliding speed was set to 300 r/min, 550 r/min, 750 r/min, and 1000 r/min under a constant applied load of 20 N, the wear rate of the 10 wt.% SiC-reinforced Mg₂Si-Al composites was reduced by 40.37%, 40.87%, 26.20%, and 25.78%, respectively, compared with the SiC-free counterparts. The wear failure mechanisms of (Mg₂Si + SiC_P)/Al composites were mainly adhesive wear and abrasive wear, but the proportion of oxidation wear increased after the addition of the SiC particles. Full article

Background/Objectives: Capric acid (CA)–therapeutic deep eutectic systems (THEDES) are emerging as a distinct class of biofunctional matrices capable of reshaping drug solubilization, permeability, and bioactivity. Methods: Relevant studies on CA–THEDES were identified through targeted database searches and screened for evidence on their design, mechanisms, and pharmaceutical performance. Results: This review synthesizes current evidence on their structural design, mechanistic behavior, and pharmaceutical performance, revealing several unifying principles. Across multiple drug classes, CA consistently drives strong, directional hydrogen bonding and drug amorphization, resulting in marked solubility enhancement and stabilization of non-crystalline or supersaturated states relative to crystalline drugs or conventional solvent systems. Its amphiphilic C10 chain further contributes to membrane fluidization, which explains the improved transdermal and transmucosal permeation repeatedly observed in CA-THEDES. Additionally, synergistic antimicrobial and anticancer effects reported in several systems confirm that CA acts not only as a solvent component but as a bioactive co-therapeutic. Collectively, the reviewed data show that CA serves as a structurally determinant element whose dual hydrogen-bonding and membrane-interacting roles underpin the high pharmaceutical performance of these systems. However, gaps remain in long-term stability, toxicological profiling, and regulatory classification. Emerging Artificial Intelligence (AI) and Machine Learning (ML)-guided predictive approaches offer promising solutions by enabling rational selection of eutectic partners, optimal ratios, and property optimization through computational screening. Conclusions: Overall, CA-THEDES represent a rationally designable platform for next-generation drug delivery, where solvent functionality and therapeutic activity converge within a single, green formulation system. Full article

With the wide application of lithium-ion batteries (LIBs), many spent LIBs will face the problem of recycling and treatment in the future. The recycling of valuable substances from battery materials is particularly important. In this paper, the spent LiNi_0.5Co_0.2Mn_0.3O₂ (S-NCM523) cathode material from used LIBs was regenerated by using the eutectic lithium salt of Li₂CO₃/LiOH. The lithium element lost by S-NCM523 was supplemented through solid–liquid contact with the molten lithium salt, restoring the layered structure at high temperatures. The successful repair of the regenerated material was verified by various characterization methods, including the elimination of the rock salt phase and the lower Li⁺/Ni²⁺ disorder. This research shows that the regenerated cathode material still has a high specific discharge capacity of 146.8 mAh/g after 100 cycles, with a capacity retention rate of 96.0%. The excellent electrochemical performance of the regenerated material demonstrates the feasibility of directly regenerating spent NCM using the molten salt method. Full article

Drugs and drug candidate compounds commonly suffer from poor solubility and permeability. One promising strategy to mediate these drawbacks is use of novel solvents, such as deep eutectic compositions. The present research aims to determine the applicability of this approach for therapeutic metal complexes on the example of [Cu(Fur)₂(Phen)] (Fur = furoate-anion, Phen = 1,10-phenantroline) and [Cu(Fur)₂(Neoc)(H₂O)] (Fur = furoate-anion, Neoc = 2,9-dimetyl-1,10-phenanthroline) with molar weight of appx. 500 Da. Interaction of the metal complexes with the deep eutectic solvent (DES) reline was studied using electron paramagnetic resonance (EPR). Minimal inhibitory concentrations of the complexes dissolved in DES and dimethyl sulfoxide (DMSO) were determined and found to be equivalent in both solvents. That is, use of reline as a solvent did not alter the functional properties of the metal complexes. Changes in the transdermal permeation of the complexes in DMSO and DES were assessed using a Franz diffusion cell. It was discovered that depending on the structure of the complex, the permeability might either increase (from 15 to 30%) or decrease (from 13 to 8%) with changes in the solvent, and this can be used to develop dosing strategies. Therapeutic eutectogels were successfully produced by impregnating SiO₂ nanoparticles with the metal complex solution in DES, facilitating convenient topical application. Full article

In the present study, ten type-V natural deep eutectic solvents (NADESs) were synthesized and comprehensively characterized, based on urea as a hydrogen-bond acceptor and three different groups of donors—glycerol, organic carboxylic acids, and carbohydrates. Their physicochemical parameters, spectral characteristics (FTIR), surface tension, and solvatochromic properties were determined using Nile Red, betaine 30, and Kamlet–Taft parameters. The densities of the systems (1.243–1.361 g/cm³) and the high values of molar refraction and polarizability indicate the formation of highly organized hydrogen-bonded networks, with the incorporated carboxyl and hydroxyl groups enhancing the structural compactness of the NADES. Surface tension varied significantly (46.9–80.3 mN/m), defining systems with low, medium, and high polarity. Solvatochromic analysis revealed high E_NR, E_T(30), and E_T^N values, positioning all NADES as highly polar media, comparable or close to water, but with distinguishable H-bond donating/accepting ability depending on the third component. The normalized Kamlet–Taft parameters show that the NADES cover a broad solvent spectrum—from highly H-bond accepting to strongly H-bond donating or dipolar systems—highlighting the potential for fine-tuning the solvent according to target applications. The obtained results highlight the applicability of these NADESs as green, tunable media for the extraction and solvation of bioactive compounds. Full article