Search Results (463)

Background/Objectives: Resveratrol is a naturally occurring polyphenolic stilbene compound exhibiting a wide range of biological activities, and it has been extensively utilized as both a food additive and a pharmaceutical active ingredient. Typically, it can be directly extracted from natural sources such as grapes, mulberries, and peanuts, or obtained through catalytic hydrolysis of polydatin. To establish an efficient and optimized method for resveratrol production, we conducted a comprehensive study to refine the acid-catalyzed hydrolysis conditions of polydatin. Methods: A high-performance liquid chromatography method was developed for the quantitative determination of polydatin and resveratrol. To identify the optimal ranges of reaction temperature, HCl concentration, and ethanol concentration, single-factor experiments were conducted by evaluating their influences on hydrolysis kinetics and resveratrol yield. Based on these results, response surface methodology incorporating a Box–Behnken design was employed to optimize the hydrolysis process, using resveratrol yield as the response variable. Furthermore, time-course experiments were performed to determine the optimal reaction duration under the established optimal conditions. Results: Single-factor experiments demonstrated that increasing temperature and HCl concentration significantly accelerated hydrolysis, but resveratrol yield increased initially and then decreased with excessive increases in either factor. To further optimize the process, response surface methodology optimization experiments were conducted at temperatures of 60, 70, and 80 °C; HCl concentrations of 1.0, 1.5, and 2.0 M; and ethanol concentrations of 75%, 85%, and 95%. The optimal conditions were identified as follows: temperature, 70 °C; HCl concentration, 1.5 M; ethanol volume fraction 85%; and reaction time, 5 h. Under these conditions, the theoretical resveratrol yield was 85.68%, and the average yield from triplicate validation experiments was 86.01% (RSD = 0.56%), which was consistent with the theoretical value. Conclusions: The optimized acid-catalytic hydrolysis process using RSM is stable, feasible, and efficient, offering a promising approach for enhancing resveratrol production from polydatin. Full article

Efficient thermal management of lithium-ion batteries is critical for the safety, performance, and longevity of electric vehicles. This work numerically investigates a battery thermal management system (BTMS) for a LiFePO₄ battery, featuring a liquid-cooling plate with novel droplet-shaped turbulators and coolant with different nanofluids. Computational Fluid Dynamics (CFD) simulations were employed to analyze the effects of cooling channel geometry, nanofluid type, nanoparticle volume fraction, coolant inlet velocity, and battery discharge rate on the system’s thermal performance and pressure drop. Results show that the droplet-shaped channel reduces the maximum battery temperature by 1.64 K compared to a conventional straight channel, owing to enhanced turbulence and larger heat-transfer area. Among different coolants, the 6% Cu–water nanofluid demonstrated the highest cooling effectiveness due to its superior thermal conductivity. To balance competing objectives, a multi-objective optimization using Response Surface Methodology (RSM) and the Non-dominated Sorting Genetic Algorithm II (NSGA-II) was performed. The optimal design was achieved with a coolant velocity of 0.097 m/s and a volume fraction of Cu nanoparticle of 3.85%, which maintained the maximum battery temperature of 299.7 K with a minimal pressure drop of 26.27 Pa at a 1.03 C discharge rate. These findings highlight that a BTMS combining droplet-shaped turbulators with a Cu–water nanofluid provides a highly effective and energy-efficient thermal management strategy. Full article

This work presents a comparative study of micro- and nano-scale fillers in liquid composite molding processes, focusing on how particle size and morphology affect resin rheology, flow behavior, and filler filtration within fiber preforms. Glass microspheres and organo-modified montmorillonite were dispersed in epoxy resin and injected through glass-mat preforms at different fiber volume fractions (ranging from 0.27 to 0.47). Our study integrates rheological characterization, in situ flow-front tracking, unsaturated permeability analysis, thermogravimetric quantification of retained particles, and microstructural observations by SEM. Despite their smaller loading, nanoclay suspensions showed a markedly higher viscosity increase than microsphere systems, yet their permeability remained nearly unchanged. In contrast, microsphere-filled resins exhibited strong filtration at the flow inlet, density-driven settling near the lower tool face, and significant permeability loss. The results demonstrate that nano-fillers, although more viscous, maintain homogeneous distribution and flow continuity, whereas micro-fillers promote cake formation and local compaction. This controlled side-by-side comparison clarifies how filler size and shape govern filtration mechanisms in liquid composite molding (LCM), providing design guidelines for processing filled resin systems without compromising part quality. Full article

Background: High-grade serous ovarian carcinoma (HGSOC) is the most common and lethal subtype of epithelial ovarian cancer and is frequently diagnosed at advanced stages. Because currently available blood-based biomarkers have limited performance in early-stage disease, there is a need to identify circulating biomarker candidates associated with early-stage HGSOC. In this retrospective multi-institutional case–control study, we evaluated whether serum extracellular vesicle (EV)-associated protein signatures distinguish early-stage HGSOC from healthy controls. Methods: Serum samples (n = 252) were obtained retrospectively from multiple institutions and included healthy controls and patients with early- and advanced-stage HGSOC. EV-associated proteins were profiled using liquid chromatography–tandem mass spectrometry (LC–MS/MS) and proximity extension assay (PEA) to identify candidate proteins enriched in early-stage HGSOC. Selected candidates were evaluated by enzyme-linked immunosorbent assay (ELISA), and tissue-level expression was examined in early-stage HGSOC specimens. A multimarker combination model was generated using a smoothed empirical estimate of hyper-volume under the manifold (SHUM) approach and internally assessed by leave-one-out cross-validation. Results: Ten EV-associated serum proteins were prioritized on the basis of differential expression and fold change and were confirmed to be expressed in early-stage HGSOC tissues. In ELISA-based analyses, the combined 10-protein EV panel distinguished early-stage HGSOC from healthy controls with an area under the curve (AUC) of 0.99 in the study dataset, whereas MUC16 (CA-125) showed substantially lower performance in this comparison. The SHUM-based model yielded a true-positive rate of 0.971, a false-positive rate of 0.057, and a Matthews correlation coefficient of 0.915 in the analyzed cohort. Several candidate proteins were differentially enriched in EV fractions but not in matched whole serum. Conclusions: Serum EV-associated proteins are altered in early-stage HGSOC and define a multi-protein signature associated with this disease state in a retrospective case–control setting. These findings support further evaluation of EV-based biomarker candidates in clinically representative and prospectively collected cohorts that include benign gynecologic conditions, symptomatic patients, and pre-diagnostic samples. Full article

Entrained gas in hydraulic oil undermines system stability. A rapid engineering method for predicting the separation efficiency of gas–liquid cyclone separators is still lacking. This study proposes an engineering-oriented predictive framework by combining the split ratio, the characteristic scale of the locus of zero vertical velocity envelope, and the axial residence time. A relative migration index, derived from maximum tangential velocity and axial residence time, is coupled with a relative overflow-pipe insertion indicator to characterize the interaction between swirl intensity and effective separation space. The separation-capability transition is described using a coupled logistic mapping. Model coefficients are identified via Eulerian–Eulerian simulations on a calibration set. The model was evaluated on isolated simulation validation sets with varying geometries and inlet gas volume fractions, yielding an R² of 0.762 and a root mean square error (RMSE) of 0.07. Particle Image Velocimetry validation tests on one representative prototype geometry gave RMSE values of 0.061 for simulation versus test and 0.108 for prediction versus test. The framework captures the macroscopic trend of separation efficiency within the investigated range, with the caveat that part of the model coefficients and intermediate inputs remain conditioned by simulation-derived quantities. Full article

Background: In pediatric practice, dose individualization often requires the manipulation of solid oral dosage forms, such as dispersing capsules in water and administering only part of the volume. Despite its frequent use, this practice is poorly documented and may lead to inaccurate dosing. Objectives: This study aimed to assess the actual dose administered when compounded hard gelatin capsules are dispersed in water and partially withdrawn, and to evaluate the influence of different manipulation protocols on dose recovery. Methods: Ten active pharmaceutical ingredients (APIs) routinely compounded as pediatric hard gelatin capsules were studied. Content uniformity was first verified according to European Pharmacopoeia (EP) requirements. One capsule was dispersed in 2 mL of water, and 1 mL was withdrawn using three protocols: (1) no mixing, (2) gentle manual mixing with immediate sampling, and (3) gentle manual mixing followed by a 10 s resting period before sampling. Drug content in the withdrawn volume was quantified using validated HPLC-UV methods. Results are expressed as the mean percentage of the theoretical dose ± standard deviation. Results: All capsules complied with EP content uniformity criteria. However, partial volume administration resulted in marked and protocol-dependent deviations from the theoretical dose. Without mixing, recovered doses ranged from 17% to 58% of the target dose, with high variability. Gentle mixing improved dose recovery, particularly for APIs forming solutions, such as captopril, thiamine hydrochloride, and clonidine hydrochloride, which achieved values close to 90%. In contrast, APIs forming suspensions consistently resulted in underdosing, even after mixing, with further reductions observed after a short resting period, indicating rapid sedimentation. Conclusions: Fractional administration of dispersed hard gelatin capsules leads to unpredictable and often clinically relevant underdosing, especially for poorly soluble APIs. Whenever possible, capsules should be compounded at the prescribed dose, and liquid formulations should be preferred when dose fractionation is required. Full article

Gas–liquid multiphase pumps are essential for deep-sea oil and gas production; however, their performance is severely limited under high gas volume fraction (GVF > 30%) conditions due to inefficient energy transfer and flow instability. In this study, a hybrid sensitivity analysis framework combining the Morris screening method and Sobol global sensitivity analysis is developed to quantitatively investigate the effects of impeller geometric parameters on pump performance at a GVF of 80%. Euler–Euler two-phase CFD simulations coupled with Python-based automated sampling are employed. The results show that the impeller outer diameter, axial length, and blade wrap angle are the three most influential parameters. The impeller outer diameter contributes 35.7% to the pressure rise, while an axial length exceeding 44 mm induces axial backflow and reduces efficiency by 8.2%. A critical wrap angle of 114° is identified for gas–liquid energy distribution, beyond which large-scale gas vortices intensify flow instability. Based on these findings, a hierarchical optimization strategy is proposed, resulting in a 6.8% improvement in efficiency and a 12.3% increase in pressure rise. Full article

Wuweiganlu (WGL) is a traditional formulation widely applied in the treatment of rheumatoid arthritis (RA), yet the identity of its bioactive constituents remains inadequately defined. In this study, ultra-performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry (UPLC-Q-TOF-MS) and untargeted serum metabolomics were employed to characterize the active components of WGL. Fraxin was identified as a principal compound from WGL. To investigate its therapeutic mechanism in RA, a series of in silico and experimental approaches were conducted. Network pharmacology analysis and RNA sequencing identified heat shock protein family member 8 (HSPA8) as a potential molecular target of Fraxin, which was further validated by molecular docking studies. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses indicated that Fraxin exerts its effects primarily by modulating cell apoptosis through the PI3K signaling pathway. In vitro experiments demonstrated that Fraxin significantly reduced inflammatory responses and downregulated HSPA8 expression in lipopolysaccharide (LPS)-stimulated fibroblast-like synoviocytes (FLs) and macrophages. In vivo, Fraxin administration markedly reduced paw swelling, alleviated bone deformities, and improved bone volume fraction (BV/TV) in male IL1RA-deficient mice exhibiting spontaneous arthritis. Histological analysis confirmed that Fraxin attenuated joint inflammation by modulating the inflammatory microenvironment. Additionally, Fraxin inhibited synovial hyperplasia by regulating mitochondrial membrane potential collapse in FLs. Functional assays revealed that this regulation occurred via the inhibition of HSPA8/PI3K/AKT signaling axis, thereby suppressing aberrant FLS proliferation and contributing to the attenuation of RA progression. Full article

This study investigates the development of a high-density W-Ni-Fe alloy using liquid-phase sintering and examines its microstructure and mechanical properties. Critical parameters, including sintering time and heating rate, were optimized to achieve enhanced density, microhardness, tensile strength, and γ-ray shielding properties. The results show that optimal sintering conditions (45 min at a heating rate of 30 K/min and a sintering temperature of 1753 K) lead to a uniform dispersion of tungsten particles, with a high-volume fraction of tungsten in the matrix and enhanced bonding within the γ(Ni-Fe) matrix. The alloy achieved a density of 16.99 g/cm³ and exhibited superior mechanical performance, with a tensile strength of 846.66 MPa and an elongation of 10.5%, as well as excellent γ-ray attenuation capabilities. These results demonstrate its suitability for nuclear applications. Full article

Performance deterioration and unstable operation are common when multistage centrifugal pumps handle gas–liquid mixtures. Here, we investigate a two-stage centrifugal pump over a wide speed range and inlet gas volume fractions (IGVFs) using experiments and CFD. The two-phase flow is simulated with a Eulerian–Eulerian two-fluid approach (liquid as the continuous phase; gas as a dispersed bubbly phase with a representative bubble diameter of 0.3 mm). Turbulence is closed using the SST k–ω model for the liquid phase and the built-in dispersed-phase turbulence treatment in ANSYS CFX. Transient pressure signals are analyzed in the time and frequency domains (FFT) to assess how rotational speed affects void-fraction distribution, overall performance, and the dominant unsteady components within the adopted modeling framework. The results show that IGVF primarily controls gas accumulation in the impeller passages: as IGVF increases, the gas phase evolves from dispersed bubbles to a central core, whereas speed mainly alters the detailed morphology via centrifugal effects. Similarity-law scaling is strongly speed-dependent in this pump: agreement is better at higher speeds and deteriorates at lower speeds where viscous effects become more influential. The dominant unsteady content also changes with speed, shifting from low-speed broadband features associated with gas redistribution to high-speed periodic components linked to blade–vane rotor–stator interaction (RSI). In addition, the downstream stage exhibits more uniform void fraction and more regular periodic signatures, consistent with an inter-stage flow-rectification effect. These observations provide practical guidance for hydraulic design and variable-speed operation of multistage pumps under gas entrainment. Full article

This research investigates wettability-induced, preferential, pressure-driven bubble nucleation of gases from a multi-gas dissolved liquid system in hydrophilic and hydrophobic glass vials. The hydrophobic glass surfaces were prepared using (heptadecafluoro-1,1,2,2-tetrahydrodecyl)triethoxysilane (HT). Degassed deionized water in a vial, placed inside a pressure cell, was saturated with a precisely controlled mixture of CO₂ and CH₄ gases at either 6000 mbar or 3000 mbar for 24 h. To initiate the pressure-driven bubble nucleation process, a 500 mbar step-down pressure was applied to the pressure cell every 15 min until bubble nucleation was observed. CH₄ and CO₂ volume fractions were measured using micro-gas chromatography (Micro-GC), while a digital microscope was employed to observe the bubble nucleation process. No bubble nucleation was observed in the case of the hydrophilic vial even when the system pressure was brought to atmospheric pressure. In the case of the hydrophobic vial, the average onset bubble nucleation pressures were 4800 mbar and 2000 mbar for 6000 mbar and 3000 mbar saturation pressures, respectively. The average feed gas concentrations during saturation were 84.44 ± 0.14% and 15.44 ± 0.2% of CH₄ and CO₂, respectively, while at the onset pressure for bubble nucleation, the concentrations shifted to 85.24 ± 0.48% and 13.12 ± 0.52% of CH₄ and CO₂, respectively, when the saturation pressure was 6000 mbar. The average feed gas concentrations during saturation were 85.12 ± 0.28% and 14.67 ± 0.1% of CH₄ and CO₂, respectively, and the average concentrations of CH₄ and CO₂ gases at onset pressure for bubble nucleation were 86.06 ± 1.21% and 12.03 ± 1.03%, respectively, when the saturation pressure was 3000 mbar. The increase in CH₄ concentration is attributed to its preferential separation during the bubble nucleation process. Full article

This study addresses the inline dielectric characterization of liquids using a prototype planar resonant sensor with two capacitively coupled spirals, fabricated by inkjet printing on a Rogers RO4003C substrate. The device includes a central hole designed to host a sample vial or a pipe, enabling contactless characterization of liquid solutions, including biological samples. Experimental validation includes stylus profilometry and optical microscopy to verify the thickness, uniformity, and continuity of the conductive film, as well as scattering parameter measurements in the frequency range from 3.5 GHz to 4.0 GHz. The frequency response exhibits two distinct resonances; the corresponding resonance parameters for each mode (resonant frequency $f_r$, amplitude, and quality factor Q) were extracted through complex-domain fitting using Lorentzian profiles. The electrical characterization of the device was assessed as a function of the effective permittivity of water–ethanol test mixtures by varying the ethanol volume fraction. The proposed sensor showed a monotonic and nearly linear response to ethanol concentration, with frequency sensitivities of approximately 20 kHz/% and coefficients of determination up to $R^2=0.99$. Full article

The growing accumulation of coal beneficiation waste represents a significant environmental and technological challenge while simultaneously creating opportunities for the resource recovery within circular economy frameworks. This study presents the development and process-oriented evaluation of an environmentally safe technology for converting coal beneficiation waste into potassium humate, with the simultaneous recovery of molybdenum compounds via alkaline extraction. The proposed solution is designed to improve resource efficiency, reduce the volume of waste directed to landfilling, and generate a high value-added product for agricultural and technological applications. The process flow includes preliminary characterization and preparation of the waste, determination of moisture, ash, and organic matter content, and the separation of metal-bearing fractions. Alkaline extraction was carried out using potassium hydroxide under controlled temperature and reaction time conditions, followed by purification and concentration of the humate solution. The process management strategy focuses on optimizing key technological parameters, including alkali concentration, solid-to-liquid ratio, temperature, and reaction time, to maximize humate yield while preserving functional groups responsible for biological activity. Comprehensive physicochemical, thermal, and mineralogical analyses confirmed the stability of the aluminosilicate matrix and the suitability of the material for alkaline processing without adverse structural degradation. Biological tests using oat (Avena sativa) demonstrated that potassium humate derived from coal beneficiation waste exhibits higher growth-stimulating effectiveness than a conventional commercial humate. Economic analysis revealed a strong correlation between humic acid content and added value, confirming the feasibility of transforming coal beneficiation waste from an environmental burden into a valuable secondary resource. Full article

Using the seeding method, nickel-based single-crystal superalloy DD6 specimens with different growth orientations were prepared in a liquid metal cooling (LMC) directional solidification furnace. Subsequent standard heat treatment was carried out, and the influence of growth orientation on the microstructure of the (001) crystal plane of the alloy after heat treatment was investigated. Results show that with the increase in growth orientation deviation angle from the <001> orientation, the area fraction of residual eutectic content is reduced, the average size and volume of pore and γ′ strengthening phase increase, and the cubicity of the γ′ strengthening phase decreases. The growth orientation does not significantly affect the morphology of residual eutectic content or the morphology of the strengthening phase of the γ′ in the dendrite cores and interdendrite regions. However, the size uniformity of the γ′ strengthening phase in dendrite cores and the width of the γ matrix channels decrease as the growth orientation deviation angle increases. Full article

Thin liquid film flows of nanofluids over porous surfaces are central to applications ranging from microfluidic thermal management to precision coating technologies. This study investigates the hydrodynamic and thermal stability of a nanofluid flowing down a non-uniformly heated inclined porous plane subject to the Beavers-Joseph slip boundary condition. Using the long-wave approximation, a nonlinear evolution equation governing the film thickness is derived. The stability characteristics are systematically analyzed via linear stability theory, weakly nonlinear analysis, and fast Fourier transform (FFT) numerical simulations. Quantitative results indicate that the porous medium permeability, density difference, and Marangoni number act as destabilizing factors; specifically, increasing the porous parameter $\beta$ (from 0 to 0.3), the density ratio ${\zeta }_0$ (from 0 to 5), and the Marangoni number $Mn$ (from 0 to 0.3) significantly reduces the critical Reynolds number and accelerates the onset of interfacial instabilities. In contrast, increasing the nanoparticle volume fraction $\varphi$ from 0 to 0.3 exerts a dominant stabilizing effect by elevating the critical Reynolds number and shrinking the unstable wavenumber domain. Furthermore, nonlinear simulations confirm that higher nanoparticle concentrations effectively suppress the saturation amplitude of disturbances, promoting the eventual stabilization of the liquid film. Full article