Search Results (1,762)

This study investigates the hybrid squeeze–flow damping characteristics of a previously developed magnetorheological (MR) mount, which integrates two vertically symmetric squeeze gaps and four flow channels. Based on the magnetic-circuit configuration, a damping-force prediction model was established specifically for the proposed hybrid structure. Magnetostatic finite element analysis (FEA) was conducted to compare the magnetic field characteristics under co-directional and opposite-direction coil excitation, and the influence of magnetic isolation components on the magnetic field distribution was additionally investigated. The results indicate that co-directional current excitation generates higher magnetic flux density in both the squeeze gaps and flow channels, enabling the magnetorheological fluid (MRF) to approach magnetic saturation at an excitation current of 2 A. The magnetic isolation components further improve the magnetic flux distribution and enhance the magnetic flux density in the squeeze gaps and flow channels. A one-way coupled numerical method combining magnetostatic FEA and computational fluid dynamics (CFD) was employed. The rheological properties of the MRF were derived from the magnetic flux density and incorporated into the CFD model via a user-defined function (UDF) to calculate the pressure losses and predict the damping force of the MR mount. The proposed model was experimentally validated over an excitation frequency range of 5–30 Hz at an amplitude of 0.15 mm, showing good agreement with the experimental results under most operating conditions. Beyond the experimentally validated range, the model was further employed to investigate the predicted damping characteristics under extended excitation conditions. The extrapolated numerical results indicate that the total damping force can reach 958.2512 N at an excitation amplitude of 0.3 mm and a frequency of 200 Hz. This result should be regarded as a model-based prediction rather than experimentally validated high-frequency performance. The squeeze mode provides the dominant damping contribution, while the contribution of the flow mode becomes increasingly significant with increasing excitation frequency. The results provide a basis for evaluating the potential of the hybrid squeeze–flow MR mount for vehicle engine vibration isolation. Full article

Wheat is one of the world’s most important cereal crops, and its technological quality is essential for the production of flour, dough and bakery products. Fusarium infection and the associated accumulation of mycotoxins may adversely affect grain composition, processing performance and food safety. This review summarizes current knowledge on the influence of Fusarium infection and associated mycotoxin contamination on the chemical composition and technological quality of wheat. A literature search was conducted in the Web of Science Core Collection, and eligible studies were included in the qualitative synthesis. The reviewed studies demonstrate that Fusarium infection generally reduces grain quality, gluten functionality, dough rheological properties and baking performance, although the magnitude and direction of changes depend on the Fusarium species, wheat cultivar, infection model and mycotoxin concentration. Considerable heterogeneity among experimental designs limits direct comparison of individual studies. By integrating evidence across grain, flour, dough and bread quality parameters, this review provides a comprehensive and comparative synthesis of the effects of different Fusarium species and associated mycotoxins on wheat technological quality and identifies major areas requiring further investigation. Full article

The development of plant-based functional beverages is often limited by inherent matrix defects, particularly undesirable off-flavors, astringency, and colloidal instability. Water kefir (WK), a highly resilient multispecies symbiotic consortium, offers a robust biorefining platform to address these challenges. This review systematically elucidates the underlying micro-ecological logic and biochemical mechanisms of WK-mediated plant matrix remodeling. We first detail how spatial niche differentiation and cross-feeding networks among lactic acid bacteria, yeasts, and acetic acid bacteria drive ecological homeostasis. Next, we highlight core molecular events that elevate sensory quality: protein unfolding for off-flavor elimination, enzymatic depolymerization of phenolics to mitigate astringency, and exopolysaccharide synthesis for rheological and flavor diffusion control. Finally, to overcome industrial scale-up challenges, we outline a precision fermentation framework, integrating systems multi-omics, real-time biomimetic monitoring, and sensory topological modeling. Ultimately, this synthesis provides theoretical guidance for the reverse flavor engineering and targeted nutritional design of novel plant-based beverages. Full article

Concrete-faced rockfill dams (CFRDs) constructed in narrow and steep valleys are strongly influenced by the mechanical interaction between the dam body and abutment bedrock. Under long-term construction and reservoir impoundment, time-dependent frictional slip along the dam–abutment interface may alter deformation transfer within the dam system. This study investigated the Dashixia extra-high CFRD through large-scale contact rheological tests and three-dimensional finite element analysis. A contact rheological model was established from interface tests and incorporated into a full-scale numerical model considering valley topography, staged construction, and reservoir impoundment. The influence of contact rheology on dam deformation, face-slab response, and peripheral-joint behavior was evaluated. The results show that contact rheology has little effect on global dam settlement but significantly increases horizontal displacement and redistributes local deformation near the abutments. Under the normal reservoir water level, the maximum upstream displacement, downstream displacement, and settlement increase by 0.7, 3.4, and 1.5 cm, respectively. Meanwhile, the maximum peripheral-joint settlement increases from 43.7 to 69.8 mm, and the maximum tensile opening increases from 8.7 to 12.8 mm. For the Dashixia CFRD, inclusion of dam–abutment contact rheology increases the predicted maximum peripheral-joint settlement and tensile opening by 59.7% and 47.1%, respectively, highlighting the greater sensitivity of local joint deformation compared with global dam settlement. Full article

Background: Three-dimensional printing (3DP) is rapidly advancing personalised medicine, yet systematic performance comparison with conventional manufacturing remains limited, particularly for plant-based formulations. Methods: This study compared tablets containing plant-based APIs (cannabidiol, apigenin, and luteolin) produced via conventional hot moulding and semi-solid extrusion (SSE) 3DP. The formulations were evaluated for physicochemical, mechanical, rheological, structural, and drug-release properties. Results: Both manufacturing methods produced tablets with comparable dimensions and mass; however, pronounced formulation-dependent differences were observed in mechanical strength, rheology, and microstructure. The molecular modelling predictions were consistent with the experimental findings. Agar–pectin exhibited the strongest predicted polymer–polymer and polymer–API interactions, including multiple hydrogen bonds, and formed a comparatively dense and cohesive matrix associated with slower API release. In contrast, the weaker interactions predicted for gelatine–pectin were associated with a less cohesive and more porous matrix that facilitated medium penetration, API diffusion, and drug release. SSE printlets generally exhibited greater porosity and more heterogeneous internal architectures than moulded tablets, resulting in enhanced drug release of approximately 95%. Micro-CT analysis provided important structural confirmation; API incorporation increased the void volume of gelatine–pectin printlets from 1.15% to 8.77%, demonstrating that disruption of polymer interactions contributed to pore formation and enhanced molecular diffusion. The observed release behaviour correlated with predicted molecular interactions and experimentally observed microstructural features, where increased porosity and weaker polymer–API interactions facilitated enhanced drug diffusion. Conclusions: Overall, SSE-3DP outperformed conventional moulding, demonstrating superior tunability and performance. This work provides a mechanistically informed strategy for designing plant-based, personalised natural products using 3DP technologies. Full article

Viscosity is a key quality parameter in cosmetic manufacturing, yet conventional rheological measurements require direct contact with the sample and are not suitable for continuous monitoring of the same specimen. This study investigates the feasibility of electromechanical impedance (EMI) sensing as a proof-of-concept approach for non-destructive monitoring of viscosity changes in cosmetic gels. Hydroxyethyl cellulose (HEC)-based model gels with HEC concentrations ranging from 0.0 to 1.0 wt% were prepared, providing viscosities between 1 and 794 cP. An acrylic-coated piezoelectric (PZT) sensor embedded in each gel was used to measure the electrical admittance spectra. The resonance peak conductance decreased progressively with increasing viscosity, whereas the resonance frequency remained nearly constant, indicating that resonance peak conductance is sensitive to viscosity-related changes in the surrounding gel. Continuous monitoring over 24 h under naturally varying temperature conditions further demonstrated that the EMI response changed consistently with the thermal behavior of the gel. These findings demonstrate the feasibility of EMI sensing as a non-destructive technique for continuously monitoring viscosity-related changes in cosmetic gels and provide a foundation for future studies using practical cosmetic formulations. Full article

The conventional fabrication of concrete block moulds is characterised by persistent challenges related to standardisation, protracted redesign processes, and an absence of structural validation, all of which undermine regulatory compliance. This study proposes a standardised parametric modelling process aimed at ensuring compliance with the technical criteria of the INEN-3066 and ASTM C90 standards. An integrative methodology combining QFD/VOC matrices with CAD-CAE tools was used to parameterise three commercial mould configurations (10, 15, and 20 cm) in SolidWorks 2023. A finite element analysis (FEA) was subsequently conducted in ANSYS 2025 R1 under iterative overloads of up to 10,000 N, complemented by a rheological analysis in SolidWorks Plastics. The results show that the “male” (punch) components exhibit consistently high stiffness, maintaining fatigue safety factors above 1.61 across all three configurations. In contrast, the “female” (die) components are the more vulnerable link in the assembly: the fatigue safety factor of the 10 cm die drops below the required threshold of 1.0 at 4000 N, compared with 6175.6 N and 9254 N for the 15 and 20 cm configurations, respectively. The rheological analysis further confirmed the feasibility of an ultrafast injection cycle, with cavity filling times below 0.11 s and injection pressures ranging from 6.105 to 12.9 MPa across all formats. It is posited that, in accordance with the parametric model, a reinforced-wall geometry should be adopted for the 10 cm die, characterised by an augmentation of wall thickness by 15% and enlarged fillet radii. This is projected to elevate its fatigue-critical load beyond 4500 N without necessitating any alteration in the external block dimensions. These findings indicate that parametric CAD-CAE-CFD digitalisation can anticipate structural failures before manufacturing, offering a computational pathway toward regulatory compliance that should be confirmed through physical prototype testing. Full article

Background/Objectives: The aim of this study was to develop and apply a novel integrated approach for predicting local mucosal tolerability of spray-dried chitosan/mannitol microspheres previously developed for nose-to-brain donepezil delivery. Methods: Microspheres were prepared by ultrasonic spray-drying, and process reproducibility was evaluated based on particle size distribution, entrapment efficiency, and process yield across independent batches. A lactose-based formulation served as a comparative control. A novel biomimetic model was developed to investigate water evaporation under simulated nasal conditions, enabling prediction of formulation dehydration and crust-like layer formation on the nasal mucosa during nasal residence time. Donepezil-loaded chitosan microspheres and their physical mixture with mannitol were used as controls. Analyses were complemented by solid-state and rheological characterization to elucidate the effects of formulation composition and processing on the observed behavior. Irritation potential was further assessed using the established slug mucosal irritation (SMI) assay. Results: Reproducible microsphere size distribution (Dv10 11.5 ± 1.1 µm, RSD 9.6%; Dv50 28.4 ± 3.9 µm, RSD 13.7; Dv90 61.3 ± 8.4 µm, RSD 8.4%), entrapment efficiency (99.6 ± 1.8%, RSD 1.8%) and process yield (40.9 ± 5.5%, RSD 13.3%) confirmed the robustness of the ultrasonic spray-drying. Replacing mannitol with lactose failed to achieve the desired particle size distribution, highlighting the key role of mannitol under the investigated processing conditions. The biomimetic model coupled with rheological studies demonstrated that chitosan-based gels formed by microsphere swelling in simulated nasal fluid, maintain viscosity, resist dehydration, and undergo rehydration. Additionally, mannitol enhanced water retention and reduced evaporation without increasing occlusivity or the risk of mucosal dehydration. Furthermore, powders containing mannitol exhibited a lower irritation potential in the SMI assay compared to chitosan microspheres alone. Conclusions: Mannitol is a critical determinant of the performance of donepezil-loaded chitosan-based microspheres, contributing to the desired particle size distribution, process reproducibility, favorable hydration and improved mucosal tolerability, thereby supporting the suitability of this platform for nasal donepezil delivery. Full article

Air-operated double-diaphragm (AODD) pumps in industrial sludge transfer suffer from gradual performance degradation due to rheological variations and component wear, yet conventional monitoring relies on scarce labeled fault data. This paper presents an unsupervised multi-sensor framework that requires no fault labels, integrating physics-informed dual health indices, HI-P (sludge load) and HI-V (mechanical stress), with a Gaussian Mixture Model anomaly detector and a physics residual attribution module. Governing equations motivate the use of these indices from five sensors: inlet and outlet flow meters (100 Hz), an air pressure transducer (100 Hz), and inlet and outlet accelerometers (1652 Hz). Trained on one healthy baseline day (86,218 one-second windows), the Gaussian Mixture Model achieves 100% day-level classification performance on the evaluated dataset (F1 = 1.00) across 455,201 test windows from nine operating days, with window-level receiver operating characteristic area under the curve (ROC-AUC) = 0.8580 and precision–recall AUC (PR-AUC) = 0.9082. Residual attribution analytically confirms that pressure residuals drive Episode 1 (HI-P peak 3.63 times baseline, Cohen’s d = 1.70) and vibration residuals drive Episode 2 (HI-V peak 5.44 times the baseline, d = 4.10), providing empirical support for the proposed physics-informed formulation without requiring fault labels. Comparisons with four unsupervised benchmarks confirm that this is the only approach that simultaneously enables label-free operation, physics-driven features, exact attribution, real-world deployment, and perfect day-level F1. Full article

The formation pressure system of ultra-deep wells is complex, and managed pressure cementing (MPC) is a commonly used technical means of safety control and cementing quality improvement. During the MPC process, pump switching operations can induce substantial annular back-pressure. The attenuation of annular back-pressure within the wellbore serves as a pivotal foundation for the precise determination of back-pressure compensation values in ultra-deep wells. Building upon the one-dimensional transient flow model of the wellbore, we developed a transient transmission model for annular back-pressure and solved it using the finite difference method. The computational results were validated against experimental data, thereby elucidating the attenuation pattern of annular pressure waves in ultra-deep wells. The findings reveal that the primary controlling factors for the attenuation of pressure waves encompass well depth, the elastic modulus of the wellbore rock, and the rheological model of the drilling fluid. As well depth increases, the pressure wave exhibits a linear decrease, with discontinuities occurring at the casing and open-hole sections. The rate of pressure wave attenuation accelerates within the open-hole interval. The lower the elastic modulus of the open-hole segment, the more rapid the attenuation rate of the pressure wave becomes. The attenuation laws of annular fluids with different rheological models are ranked as follows: Power-law model > Herschel–Bulkley model > Bingham model. Under the computed well conditions, the pressure of the power-law fluid decreases to 85% of its initial back-pressure value. This research provides theoretical underpinnings for the design and execution of on-site MPC operations. Full article

Background: Diabetic foot ulcers (DFUs) are chronic wounds characterized by persistent inflammation, oxidative stress, impaired angiogenesis, and defective extracellular matrix remodeling. Current therapeutic approaches remain insufficient for refractory diabetic wounds due to limited drug retention and inadequate regulation of the wound microenvironment. This study aimed to develop a centipede-derived protein fraction-loaded nanocapsule hybrid hydrogel for sustained bioactive delivery and diabetic wound repair. Methods: A bioactive protein fraction was isolated from processed medicinal centipede material and screened using cellular compatibility assays. The selected tropomyosin-containing protein fraction was incorporated into nanocapsules and subsequently integrated into a gallic acid-modified polyacrylamide hydrogel matrix. The physicochemical properties, antioxidant activity, rheological behavior, and protein release characteristics of the nanocapsule-hydrogel system were systematically evaluated. A streptozotocin-induced diabetic rat wound model was established to assess therapeutic efficacy through wound closure analysis, histological staining, and immunohistochemical evaluation. Results: The prepared nanocapsules exhibited a spherical morphology, nanoscale size distribution, and sustained protein delivery capability. The PAM-GA hydrogel demonstrated antioxidant activity, injectability, shear-thinning behavior, self-healing ability, and enhanced retention of protein release. In vivo experiments showed that the PT@NC@PAM-GA hydrogel significantly accelerated wound closure and promoted tissue regeneration, accompanied by enhanced angiogenesis, collagen deposition, and reduced inflammatory responses. Conclusions: The centipede-derived protein fraction-loaded nanocapsule hybrid hydrogel effectively integrates bioactive protein delivery with a multifunctional hydrogel matrix, providing a potential strategy for sustained treatment of diabetic foot ulcers. Full article

The formation of oil–water emulsions following reservoir-water breakthrough is widely observed during oil production. The viscosity of these polydisperse systems may increase sharply with increasing water cut, creating substantial operational difficulties in well-gathering systems and increasing hydraulic pressure losses. The rheological behaviour of oil emulsions is influenced by the phase ratio, flow velocity, degree of dispersion, temperature and several other parameters. However, no generally applicable model is currently available for describing the rheological behaviour and predicting the properties of oil emulsions, which are anomalous and rheologically complex systems. Therefore, developing a reliable method for estimating the viscosity of stable emulsions while accounting for increasing water content is of considerable practical importance. This study evaluates existing empirical correlations used to characterise the rheological properties of oil emulsions. The analysis shows that their application under oilfield conditions is associated with several limitations and that, in many cases, they are unsuitable for solving practical engineering problems. Accordingly, a mathematical model was developed and validated for estimating and predicting the viscosity of structurally stable oil emulsions as a function of water cut. The proposed model demonstrated good agreement with the experimental data and may be used for engineering calculations related to the production and transportation of water-cut oil. Full article

Accurate wellbore-pressure prediction is essential for safe drilling and pressure management in ultra-deep wells, where high temperature and pressure strongly alter drilling-fluid rheology. Existing rheological-parameter models are often calibrated for specific fluids and narrow temperature–pressure ranges, limiting their use in ultra-deep-well hydraulics. We measured three water-based drilling fluids at temperatures and pressures up to 210 °C and 206.5 MPa, compared seven rheological models, and developed a multidimensional evaluation method considering global fitting accuracy, extreme-condition performance, low-shear-rate representation, absolute shear-stress deviation, and model complexity. Using ambient-condition Herschel–Bulkley (H-B) parameters as baselines, we proposed a temperature–pressure (T-P)-coupled correction model requiring fluid-specific calibration to predict H-B parameters over the tested range. The fluids exhibited temperature-induced thinning, pressure-induced thickening, and shear-thinning behavior. The H-B model showed the best overall performance, with mean R² values above 0.997 and mean absolute percentage errors below 2.5% for all fluids. Substituting the corrected parameters into the H-B equation yielded mean shear-stress errors no greater than 4.04%. Field validation showed that the T-P-coupled model reduced the mean circulating-pressure-loss error from 2.72% to 0.78%. This approach provides practical inputs for rheology estimation and circulating-pressure calculation in ultra-deep wells under wide temperature and pressure conditions. Full article

Satellite droplets and macroscopic distortions, induced by the non-Newtonian rheological behavior of ceramic inks, severely compromise the 3D inkjet printing of multilayer ceramics. To address these issues, we establish a two-phase fluid dynamics model coupling the Level Set method with the Carreau fluid model. The synergistic regulation mechanisms of the piezoelectric driving waveform, initial jet velocity, and pulse width under a high-shear field are elucidated. The results demonstrate that under the excitation of a rectangular pulse with an initial jet velocity of 6 m/s and a pulse width of 10–30 µs, the inertial force, surface tension, and internal non-Newtonian viscous dissipation of the fluid reach an optimal dynamic balance. This facilitates the on-demand ejection of spherical droplets while mitigating the formation of satellite droplets. Based on this, a 10 mm × 10 mm × 2 mm multilayer alumina ceramic packaging substrate was successfully fabricated, with the maximum relative dimensional error reduced from 2.6% to 1.4%. This study provides new insights into improving the 3D inkjet printing accuracy of ceramic devices. Full article

Cataracts are the leading cause of reversible blindness worldwide; this condition results from the aggregation of lens proteins. Currently, surgery remains the only treatment; however, there is growing interest in non-surgical approaches, including the use of bioactive compounds incorporated into nanostructured systems designed to enhance solubility, enable controlled release, and improve bioavailability and bioactivity. Among the bioactive compounds investigated, curcumin has attracted considerable attention due to its antioxidant and anti-inflammatory properties, positioning it as a potential anticataractogenic agent. In the present study, curcumin-loaded nanoemulsion was developed via ultrasonication and characterized by average particle size, D90 percentile, ζ potential, and rheological behavior. In addition, its anti-cataract efficacy was evaluated both using an in vivo model in rats and an ex vivo model employing human cataract samples. The resulting curcumin-loaded nanoemulsion exhibited an average particle size of 152 ± 19.79 nm with a monomodal distribution, along with good physical stability over time. The nanoemulsion exhibited apparent viscosity between 30 and 25 mPa·s, at shear rate values (100 to 0 s⁻¹), indicating slight shear-thinning behavior. Regarding the effect on cataracts, in the in vivo model, cataract reversal was observed. Furthermore, ex vivo isothermal titration calorimetry (ITC) analyses indicated exothermic heat exchange between the curcumin nanoemulsions and cataract fragments, consistent with binding interactions occurring within lens components, likely involving crystallin proteins. These findings provide biophysical and in vivo evidence that intravitreally administered curcumin-loaded nanoemulsions not only prevent but actively reverse lens opacity, positioning them as a promising non-surgical therapeutic approach for cataract treatment. Full article