Herein, we report a crosslinked (cl) hydrogel of spent tea leaves (STLs) with two monomers, 2-acrylamido-2-methyl-1-propanesulfonic acid (AMPSA) and acrylamide (Am), via free radical graft copolymerization using potassium persulfate and N, N′-Methylenebisacrylamide as the initiator and cross-linker, respectively. The as-synthesized hydrogel, STLs-cl-Poly(AMPSA-co-Am), was characterized using FTIR, FESEM-EDX, TGA, BET, zeta potential, and surface charge analysis. The STLs-cl-Poly(AMPSA-co-Am) hydrogel was evaluated for the adsorption of cationic dyes, namely, methylene blue (MB), and crystal violet (CV) from their aqueous solutions using various parameters, such as time (0–90 min), temperature (25–50 °C), pH (2.0–10.0), and concentration (25–400 ppm). The adsorption process was analyzed using kinetic models, namely pseudo-first-order, pseudo-second-order (PSO), and Elovich, and isotherm models, such as Langmuir, Freundlich, and Temkin. The maximum removal efficiencies for MB and CV were 90.50 ± 0.63% and 85.62 ± 0.59%, respectively. The adsorption process was best described by PSO and Langmuir model, confirming monolayer adsorption, with maximum adsorption capacities of 375.53 ± 6.33 and 344.05 ± 4.49 mg g−1 for MB and CV, respectively. The STLs-cl-Poly(AMPSA-co-Am) hydrogel showed high reusability for 8 cycles with a cumulative adsorption capacity of 682.76 mg g−1 for MB and 622.43 mg g−1 for CV. Thus, a novel STLs-based hydrogel was developed via free-radical graft copolymerization, in which STLs function simultaneously as a precursor and bio-filler, providing ample functional groups and a porous structure that enhance interactions with cationic dyes. This dual functionality enables effective biomass waste valorization for cost-effective, reusable, and environmentally sustainable dye removal from aqueous solutions.

Delaying Leidenfrost effect is of great importance for effective cooling of electronic devices. In this article, the effects of different droplet properties on boiling phenomena have been experimentally studied. To endow the droplets with different properties, the sodium dodecyl sulfate (SDS) and Al2O3 nanoparticles are added to deionized water. The Al2O3 nanofluids with SDS (NFWS) and without SDS (NFNS) are prepared with concentrations from 0.1% to 0.5%, respectively. Static evaporation curve tests are conducted. And images of single droplet impacting on the heated aluminum surface (70 °C to 350 °C) under various impact velocities and concentrations are captured continuously. The results indicate that the maximum evaporation time of the NFWS droplets decreases with increasing concentration. However, the peak value of the maximum evaporation time occurs at a concentration of 0.3% for the NFNS droplets. The maximum spreading factor increases as the impact velocity rises and decreases as the nanofluid concentration increases. For the NFWS droplets, a larger maximum spreading factor is observed. A boiling regime related to impact velocities and surface temperatures is presented. The Leidenfrost temperature of NFNS droplets is higher than that of NFWS droplets at low impact velocity. As the impact velocity increases, it shows an opposite trend. Finally, the predictive models for the maximum spreading factor and dynamic Leidenfrost temperature are established. The higher prediction accuracy of models can be obtained when considering the NFWS and NFNS droplets, respectively. This study can provide valuable insights into the impact behaviors of Al2O3 nanofluid on high-temperature surface.

Zeolitic imidazolate framework-8 (ZIF-8) is a highly effective metal-organic framework (MOF) that was synthesized and characterized to examine its exceptional adsorption of Allura Red (AR) using UV-Vis spectrophotometry at a wavelength of 504 nm. The highest extraction efficiency (95%) at pH 6, with an equilibrium time of 30 min, using 8 mg of adsorbent for 10 ml of solution containing 2 mg L−1 of Allura Red, was obtained without the addition of salt, with an adsorption capacity of 36.49 mg g−1. A desorption study was performed in the presence of 0.5 mol L−1 ammonia solution for Allura Red. The synthesized ZIF-8 was characterized using several techniques, including X-ray diffraction (XRD), Fourier-transform infrared (FT-IR) spectroscopy, Field emission scanning electron microscopy (FESEM), and Brunauer–Emmett–Teller (BET) surface area analysis. Significantly, the point of zero charge (pH PZC) for ZIF-8 was found to be 8, emphasizing its efficiency. A variety of isotherm models were employed to evaluate adsorption performance, including the Langmuir, Freundlich, Dubinin-Radushkevich, and Temkin models. The equilibrium data indicated that the Langmuir model best described the adsorption process of (AR). For the adsorption kinetics, the pseudo-first-order, pseudo-second-order, and intraparticle diffusion models were tested. The results clearly showed that the adsorption followed the pseudo-second-order and intraparticle diffusion models. Additionally, thermodynamic parameters, including Gibbs free energy (ΔG), entropy (ΔS), and enthalpy (ΔH), were assessed. The results clearly showed that the adsorption process was both exothermic and spontaneous, further supporting the effectiveness of ZIF-8 in removing pollutants.

Background This study involved improving solubility of ondansetron HCl (ODN-HCl) through solid dispersion followed by its inclusion into orodispersible films (ODFs) for improved chemotherapy-induced nausea and vomiting (CINV) management. Research design and methods Face-centered central composite design (FCCD) was used to optimize ODN-HCl solid dispersions through the combination of PEG 6000 and PVP K30 carriers. Solvent-evaporation method was used for SD preparation and characterized for solubility, particle size, zeta potential and polydispersity index. The optimized SD obtained integrated into ODFs of HPMC E50 matrix was evaluated for thickness, disintegration time, in-vitro drug release, and ex-vivo permeability. Results The FCCD yielded quadratic mathematical models (p < 0.0001) which indicated PEG 6000 and PVP K30 were key determinants for SD properties. Optimized SDs presented increased solubility levels of 4.5 times (0.2685 mg/ml compared to pure drug solubility of 0.0252 mg/ml) combined with lowered crystal formation that XRD and DSC measurements confirmed. The ODFs showed a quick disintegration time (<35 s) that combined with uniform drug distribution (90%) and drug release exceeding 90% within 10 min. Stability tests across six months maintained uniform results. Conclusion The FCCD-optimized SDs increased ODN-HCl solubility with ODF delivery system which supports rapid drug release for CINV therapy.

Clay-rich sandstones present significant challenges to enhanced oil recovery (EOR) due to the complex behavior of their abundant clay minerals, particularly during chemical flooding strategies. This study investigates how clay mineralogy, chemical interactions, and surfactant formulation collectively influence reservoir permeability, surfactant retention, and oil recovery efficiency. Through a critical review of recent literature, the research examines the mechanisms of clay swelling, fine particle migration, chemical adsorption, and the influence of environmental factors such as salinity and pH on surfactant-clay interactions. Experiments referenced include swelling, zeta potential, surfactant adsorption measurements, and core flooding trials under varying reservoir conditions. The results identify that montmorillonite and illite promote higher surfactant and chemical retention, exacerbating permeability loss. Specifically, surfactant retention can reach up to 0.22 mg/g of rock in high-clay-content cores, significantly increasing operational costs. While excessive surfactant adsorption by clays reduces EOR efficiency, appropriate surfactant selection and the synergistic use of low salinity or alkaline additives can mitigate detrimental effects. For instance, studies show improved oil recovery rates as high as 27.02% with optimized nonionic surfactants, and recovery factors up to 71.86% when integrating nanoparticles with surfactant systems. However, a persistent tradeoff exists between recovery gains and formation damage risks, which must be carefully balanced. Ultimately, the study underscores the necessity of matching surfactant systems and injection protocols to reservoir-specific clay mineralogy and salinity conditions. The findings provide a basis for optimizing EOR formulations to improve oil recovery in complex clay-bearing reservoirs. Meanwhile, future research should focus on developing advanced surfactants with minimal retention and exploring in situ monitoring to further reduce the impact of clays on oil production.

This study introduces a new water-soluble aminoketone/hydroxyethyl bifunctional clay shrinkage agent, HEAMC (2,6-bis-[(2-hydroxyethyl) aminomethyl] cyclohexanone), synthesized via the Mannich reaction to address clay swelling in water-sensitive oil reservoirs. FTIR spectroscopy confirmed the presence of aminoketone and hydroxyethyl groups in HEAMC. Performance evaluations showed that a 0.5 wt% HEAMC solution achieved a 34.29 ± 0.25% shrinkage rate of Na-montmorillonite (Na-MMT), surpassing the 28.57 ± 0.61% achieved with 3 wt% KCl, and demonstrated superior temperature stability up to 100 °C. Multi-scale characterization (XRD, Zeta potential, TGA, SEM) revealed that HEAMC increased Na-MMT particle size, restructured microtopography, reduced interlayer spacing, and expelled interlayer water. The dual-action mechanism involves clay particles agglomeration dewatering as the primary process, complemented by electrostatic adsorption between cationic aminoketone groups and clay negative charges, and hydrogen-bonding reinforcement by hydroxyethyl groups. This study provides a theoretical foundation for developing low-concentration, thermostable organic clay shrinkage agents by integrating clay particles agglomeration dewatering, electrostatic neutralization, and hydrogen-bonding interactions.

This study investigates the physicochemical interactions between cocarboxylase (a hydrophilic derivative of thiamin) and three anionic surfactants, sodium cholate (NaC), sodium deoxy cholate (NaDC), and sodium dodecyl sulfate (SDS), in aqueous media. A multi-technique approach comprising UV–Vis spectroscopy, conductivity, surface tension, and viscosity measurements was employed to examine micellization, interfacial properties, and encapsulation efficiency. The critical micelle concentration (CMC) of NaC, NaDC, and SDS decreased in the presence of cocarboxylase. The values of binding constant indicate to stronger interaction between cocarboxylase and NaDC micelles as against NaC and SDS micelles. Thermodynamic parameters indicate that the micellization and drug-micelle interaction are spontaneous processes. Morphological analysis confirmed spherical micelle formation across all systems. Overall, the finding emphasize the potential of the bile salt micelles, especially NaDC, as effective carriers for the encapsulation and delivery of hydrophilic molecules such as cocarboxylase.

The dispersion and aggregation states of particles in slurries critically influence industrial processes such as ceramic capacitor and lithium-ion battery production. Accurate evaluation of these states is especially important for highly concentrated slurries. Although laser diffraction/scattering methods are widely used to measure particle size distributions, they often require significant dilution of the slurry, raising concerns about the relevance of the data to the original state. This study examines the impact of dilution on evaluating particle dispersion and aggregation in aqueous alumina slurries. Two types of systems were analyzed: (1) simple systems with controlled pH and ionic strength, and (2) complex systems containing dispersants and binders typical of ceramic processing. Undiluted slurries were evaluated using an X-ray transmission particle size analyzer and apparent viscosity measurements. After dilution by over a thousand-fold, particle size distributions were re-measured using laser diffraction. In simple systems, particle sizes before and after dilution showed a strong correlation, but differences in dispersion states became less apparent. In contrast, complex systems with dispersants and binders exhibited marked changes in dispersion behavior upon dilution, particularly when excess dispersant was present beyond optimal adsorption. This led to a poor correlation between pre- and post-dilution states. The findings highlight that dilution can obscure the actual dispersion and aggregation behavior in concentrated slurries. Therefore, conventional dilution-based particle size measurements may not reliably reflect the true characteristics of such systems, especially in the presence of additives.

In this study, pine cone waste (PCW) was successfully transformed into valuable adsorbents by utilizing innovative activation methods. The controlled activation process employs a highly effective two-step method using KOH at a 1:2 impregnation ratio, followed by thermal activation in a tubular furnace, ensuring optimal conditions under an inert nitrogen (N2) atmosphere for maximum efficiency. The obtained activated carbon with the following characterization: specific surface area of 421 m2 g−1, pore radius of 0.32 nm, a yield of 72.6%, an ash content of 1%, a humidity rate of 3%, a pHzpc of 7.7 and iodine index of 888.5 mg g−1 was used to reduce the toxicity of parachlorophenoxyacetic acid (p-CPA) and Linuron (Lin) herbicides. Maximum capacities of 284.81 ± 7.88 mg g−1 and 63.37 ± 2.45 mg g−1 were reached for p-CPA and Lin, respectively. Data fit well Freundlich and Redlich-Peterson models, indicating multilayer adsorption with strong adsorbent-adsorbate interactions. Kinetic studies revealed the involvement of both physisorption and chemisorption mechanisms. The diffusion constant rate (kid ), decreased with the initial concentration in the p-CPA adsorption but increased in the Lin adsorption process. Thermodynamic analysis confirmed the spontaneous nature of adsorption for both herbicides, the endothermicity of p-CPA, and the exothermicity of Lin herbicides. Finally, PCW can be converted into activated carbons and effectively used for herbicides removal from water.

Mannose erythritol lipid (MEL-B) lamellar vesicles are promising biocompatible carriers for skincare, but their tendency to form unstable, micron-sized vesicles when used alone limits their application. Herein, we introduce the Gemini surfactant sodium dilauramidoglutamide lysine (DLGL) to overcome this limitation. Highly stable MEL-B-based unilamellar nanovesicles (< 100 nm) are formulated with DLGL. At an optimal DLGL/MEL-B ratio of 0.2, the binary vesicles exhibit excellent stability, showing negligible size variation (< 3 nm) across different storage temperatures and maintaining a zeta potential absolute value consistently above 30 mV. These vesicles significantly enhance the skin permeation of hydrophilic Dendrobium officinale oligosaccharides (DOOS), achieving twice the cumulative permeation compared to the pure DOOS solution at 8 h. Moreover, the formation of ternary vesicles by incorporating lecithin further enhance transdermal delivery.