The fluid catalytic cracking (FCC) process plays a critical role in maximizing gasoline yield; however, its operation is highly complex due to nonlinear process interactions in feedstock composition. In the present study, a data-driven, ensemble learning framework is developed to enhance gasoline yield prediction accuracy. A three-stage feature selection strategy integrating the Variance Inflation Factor (VIF), Recursive Feature Elimination with Cross-Validation (RFECV) and Sensitivity Analysis was employed to identify the most informative variables prior to model development. Particle Swarm Optimization (PSO) was used for hyperparameter optimization of the proposed Extremely Randomized Trees-based model (XRTR). Model performance was evaluated against baseline models, and the proposed VIF–RFECV–PSO–XRTR framework demonstrated superior predictive performance for improved gasoline yield. In single train–test evaluation, the model achieved R2 = 92.26%, RMSE = 0.3750, and MAE = 0.1008. Cross-validation further confirmed its robustness, with R2 = 92.20% (±0.55) at k fold = 10.
The occurrence of vibrational resonance (VR) in a modulated spatially varying periodic system is investigated in this study. A modulation profile possessing a harmonic order is exerted on a spatially periodic function to yield a modulated landscape. The dual-frequency driven modulated system is subsequently treated within the separation of motion scheme, to yield a quantifier for VR in the form of response amplitude. Applying a linearly damped regime, within the domain of the fast field drive and for different values of the harmonic order, multiple resonances were detected in the response profile for particular values of the weak excitation frequency component. All analytical deductions were confirmed through numerical simulations, which demonstrated a reasonable level of agreement. Comparisons with related studies reveal the distinctive influence of harmonic order modulation in enhancing and transforming VR responses for specific operating values of field parameters. The impact of the modulating function in transforming features of the forced system, viz., effective potential and resonant frequency under VR analysis, provides avenues of active enrichment of the output signal at the low frequency. These unique characteristics may provide pertinent prospects for dynamical systems that adopt spatially periodic states.
In the present study, ultrasonication combined with enzymatic covalent bonding with arabinoxylan (AX) induced by laccase were used to modify the conformational and functional properties of whey protein concentrate (WPC), and the effects on high internal phase emulsions (HIPEs) were also investigated. The results showed that the optimal covalent reaction mass ratio of AX to WPC was 3:2 through characterization, and 10 min ultrasonication-pretreatment of WPC facilitated the formation of WPC-AX conjugates and improvement of solubility and emulsifying property. The WPC-AX conjugates can quickly adhere to the oil-water interface and form a more compact three-dimensional network structure. The formation of this structure can slow down the oxidation rate of the encapsulated oil droplets. The HIPEs formed by WPC-AX conjugates exhibited smaller droplet size, uniform microstructure, elasticity-dominated characteristics with a significant increase in apparent viscosity and better stability during the process of gastric digestion.
High internal phase emulsions (HIPEs) prepared from protein-polysaccharide complex systems are attracting attention for their potential applications in the food, pharmaceutical and cosmetic fields. In the present study, whey protein concentrate (WPC) was used as a raw material and was structurally and functionally modified by pH 12 shift pretreatment (0, 30, 60, and 90 min), which induced partial unfolding of proteins and exposure of active groups. Subsequently, horseradish peroxidase (HRP)-catalyzed glycosylation grafting of arabinoxylan (AX) and transglutaminase (TGase)-mediated covalent coupling of carboxymethyl chitosan (CMCS) were employed for dual modification of the pretreated WPC. The structural and functional traits of the modified WPC, including degree of interactions with polysaccharides, Fourier transform infrared spectroscopy, fluorescence spectra, solubility, emulsification properties and interfacial adsorption behavior, and the effects on HIPEs were systematically investigated. The optimal enzymatic glycosylation modification conditions were determined to be pH 12 shift pretreatment for 30 min, at which WPC exhibited the highest grafting degree with AX and CMCS, and WPCAX conjugates achieved optimal emulsifying activity and solubility among all the samples including WPC and WPC/AX mixtures, validating the synergistic effect of pH shift and enzymatic glycosylation. Microstructural analysis of optical morphology and CLSM images showed that the glycosylated WPC-stabilized HIPEs had smaller droplets and more homogeneous droplet distribution compared with that of HIPEs stabilized by WPC and WPC/ AX(CMCS) mixture. 30-WPC-AX emulsion exhibited the best freeze-thaw stability, with no water-oil segregation after three freeze-thaw cycles. 30-WPC-CMCS emulsions had larger G' and G", and higher apparent viscosity than natural WPC and 30-WPC-AX emulsions. This study is of great significance for the preparation of food-grade HIPEs, which are also informative in the study of protein-polysaccharide conjugates in oil-water interfacial stability.
This study developed whey protein concentrate (WPC)-polysaccharide (arabinoxylan and carboxymethyl chitosan) conjugates via high-pressure homogenization (HPH)-assisted enzymatic glycosylation for stabilizing oil-in-water high internal phase emulsions (HIPEs). Optimal conjugation at 30 MPa significantly enhanced the functional properties of WPC, including solubility, emulsifying, and foaming activities, while reducing its particle size and increasing absolute zeta potential. Meanwhile, structural analysis indicated protein unfolding, evidenced by a decrease in ordered secondary structures (α-helix, β-sheet, β-turn) and an increase in random coils, which facilitated the adsorption of the conjugation at the oil-water interface. Compared with the control group, the HIPEs stabilized by the conjugates exhibited smaller droplet size, higher absolute zeta potential, uniform microstructure, significantly improved oxidative stability, elasticity-dominated characteristics with a significant increase in apparent viscosity, and excellent storage stability during the storage period.
