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In this study, Janus nanoparticles were prepared and used to construct Pickering emulsion as an emulsifier in presence of lipase. The results showed that Janus nanoparticles could be used to stable water phase in emulsion and the average particle size of emulsion was 60 μm. Phytosterol ester was successfully synthesized in Pickering emulsion catalytic system by using oleic acid as acyl accepter, and the phytosterol conversion reached 91.65 ± 2.07% under the following conditions: emulsifier amount of 1.0 wt%, oil-water ratio of 6:1, phytosterol concentration of 110 mmol/L, lipase dosage of 20 g/L, reaction temperature of 45 °C. Compared with biphasic catalytic system, Pickering emulsion catalytic system could enhance the catalytic efficiency and shorten the reaction time due to large interface area and short molecule diffusion distance. At the end of reaction, Janus nanoparticles could be recovered by simple centrifugation, the relative activity of lipase remained 72.89 ± 1.83% after repeated use for 6 times. Overall, this paper provides a novel and high efficiency interfacial biocatalysis technique for the synthesis of phytosteryl oleate. [Display omitted] • The preparation method of the Janus nanoparticles is simple and effective. • The Janus nanoparticles with great amphiphilicity and emulsification. • Pickering emulsion exhibit higher catalytic efficiency. • The compounds of phytosteryl oleate are analyzed by HPLC and LC-MS. [ABSTRACT FROM AUTHOR]

• A comprehensive stiffness model of intermediate bearing is presented. • A reduced model of dual rotor-bearing-casing coupling system is developed. • The effects of typical parameters on the vibration of the system are discussed. • The mechanism of the comprehensive stiffness and system vibration is revealed. This paper focuses on the vibrational properties of a dual rotor-casing coupled system with nonlinear clearance in the intermediate bearing, considering both the oil film stiffness and Hertzian contact stiffness between rolling elements and raceways. A comprehensive stiffness model for the intermediate bearing has been developed based on elastohydrodynamic lubrication (EHL) and Hertz contact theory. Subsequently, a dynamical model of the dual rotor-bearing-casing system is established using the finite element method, thereby verifying the feasibility of simulating the casing with beam elements. The dimensionality of the system equation is reduced using the fixed-interface component mode synthesis (CMS) method, and the resulting reduced-dimensionality equation is solved using the improved Newmark- β method. The effects of casing support, rotational speed, and radial clearance on the vibration characteristics of the system are investigated. Then, the comprehensive stiffness and coupled vibration characteristics of the system are analyzed to elucidate its intrinsic mechanism. Finally, the contact characteristics within the intermediate bearing under dynamic load are also studied. The results indicate that the support stiffness of the casing has a more significant impact on the second resonance caused by both the inner and outer rotors. The system is prone to experiencing varying compliance (VC) resonance at low rotational speeds. The excessive bearing clearance leads to complex vibrational characteristics of the system, making it challenging to predict its motion. The impact of minor changes in stiffness on system vibration is small when the comprehensive stiffness is large. At this time, the limited effect of oil film stiffness allows it to be disregarded in terms of comprehensive stiffness. Furthermore, the speed significantly influences the contact characteristics within the intermediate bearing under the unbalanced force of the rotor and gravity. [ABSTRACT FROM AUTHOR]

Adversarial examples have a simple additive structure that the clean sample is added with delicate devised noise. Inspired by such an observation, we find that the prediction of the network on adversarial examples can also be decoupled into a simple additive structure, which is the sum of clean samples and adversarial perturbations in terms of the model prediction (called the decoupling principle). Thus, our findings can be served as a useful tool to gain insight into the underlying relationship between the inputs and the outputs of the model. However, although the adversarial examples generated by existing attack methods can satisfy the decoupling principle, the proportion is small. In this paper, we formulate the above issues as an optimization problem with multi-constrains, and we propose a generative model to generate adversarial examples that satisfy the decoupling principle and simultaneously obtain high attack performance. Specifically, we first adopt the adversarial loss to ensure the attack performance. Then, we devise a decouple loss to guarantee the decoupling principle. Moreover, we treat the Euclidean distances of perturbation as regularization terms to maintain visual quality. Extensive experiments against various networks on ImageNet and CIFAR10 show that the proposed method performs better than comparison methods in the comprehensive metric. Furthermore, transferability results suggested that adversarial examples that satisfy the decoupling principle show better transferability. • We find that the prediction of adversarial examples can be decoupled into the summation of clean samples and perturbations in terms of the model prediction, which can be a useful tool to gain insight into the underlying relationship between the inputs and the outputs. • We propose a generative model-based method to craft the adversarial perturbation, which satisfies the decoupling principle and simultaneously has superior attack performance. Moreover, the decouple loss is devised to guide the generative model for ensuring the decoupling principle. • We conduct extensive experiments against different networks on the complex ImageNet and simple CIFAR10 datasets. Experiment results suggest that the proposed method outperforms the comparison methods by a large margin in the devised metric that balance the attack performance and decoupling principle. [ABSTRACT FROM AUTHOR]

[Display omitted] • Stability, degradation and in vitro simulation characteristics of emulsions. • Oleogel-in-water emulsion with 3 % hemp seed protein had better stability. • The half-life of cannabinol in oleogel-in-water emulsion was 131.82 days. • Bioaccessibility of cannabinol in oleogel-in-water emulsion was 58.0 %. The present study focused on investigating the stability and in vitro simulation characteristics of oil-in-water (O/W) and oleogel-in-water (Og/W) emulsions. Compared with O/W emulsion, the Og/W emulsion exhibited superior stability, with a more evenly spread droplet distribution, and the Og/W emulsion containing 3 % hemp seed protein (HSP) showed better stability against environmental factors, including heat treatment, ionic strength, and changes in pH. Additionally, the stability of Δ9-tetrahydrocannabinol (Δ9-THC) and cannabinol (CBN) and the in vitro digestion of hemp seed oil (HSO) were evaluated. The half-life of CBN in the Og/W emulsion was found to be 131.82 days, with a degradation rate of 0.00527. The in vitro simulation results indicated that the Og/W emulsion effectively delayed the intestinal digestion of HSO, and the bioaccessibility of Δ9-THC and CBN reached 56.0 % and 58.0 %, respectively. The study findings demonstrated that the Og/W emulsion constructed with oleogel and HSP, exhibited excellent stability. [ABSTRACT FROM AUTHOR]

[Display omitted] • Sn-1-lysophosphatidylcholine underwent acyl migration due to structural instability. • Acyl migration rate was higher under acidic or alkaline conditions. • Nitrogen/vacuum increased yield of conjugated linoleic acid lysophosphatidylcholine. • The maximum yield was achieved when the vacuum pressure was 13.3 KPa. Sn -Glycerol-3 - phosphatidylcholine (GPC) was prepared by hydrolysis of phosphatidylcholine (PC) catalyzed by phospholipase A 1 (PLA 1). Nitrogen flow assisted the esterification of conjugated linoleic acid (CLA) and GPC to produce conjugated linoleic acid lysophosphatidylcholine (LPC − CLA). The effects of different reaction conditions on the PC conversion and acyl migration rates were investigated, and the acyl migration mechanism under acidic and alkaline conditions was studied. In addition, the optimum conditions for the esterification of CLA and GPC were selected. The optimal condition for the hydrolysis of PC was an enzyme loading of 5 %, pH of 5, reaction temperature of 50 ℃, and reaction time of 3 h. The results also showed that the maximum esterification rate reached 82.37 % at an enzyme loading of 15 %, CLA/GPC molar ratio of 50:1, and vacuum pressure of 13.3 kPa. This study not only improved the bioavailability of PC but also effectively increased the content of LPC − CLA. [ABSTRACT FROM AUTHOR]

• Hemp seeds were pretreated with a combination of ultrasound and ethanol. • The degradation rate of Δ9-THC was 92.14 % at ultrasonic power of 200 W for 30 min. • After optimizing the extraction conditions, the oil recovery rate reached 88.38%. • The Δ9-THC in the oil sample was 9.58 mg/kg. In this study, ultrasonic-ethanol pretreatment combined with AEE was developed for oil extraction from hemp seeds. The oil yield reached a maximum of 23.32 % at 200 W ultrasonic power and 30 min ultrasonic time, at this point, the degradation rate of Δ9-THC was 83.11 %. By determining the composition of hemp seed before and after pretreatment, it was shown that ultrasonic-ethanol pretreatment reduced the protein content of the raw material. An enzyme mixture consisting of pectinase and hemicellulase (1/1/1, w/w/w) was experimentally determined to be used, and the AEE extraction conditions were optimized using the Plackett-Burman design and the Box-Behnken. The optimal conditions were determined to be pH 5, total enzyme activity of 37,800 U/g, liquid–solid ratio of 10.4 mL/g, enzyme digestion temperature of 32 °C, enzymatic time of 189 min, and oil recovery of 88.38 %. The results of confocal laser scanning microscopy (CLSM) and scanning electron microscopy (SEM) showed that the emulsion formed during ultrasonic ethanol pretreatment was not uniformly distributed, and the droplets appeared to be aggregated; and the irregular pores of hemp seed increased after pretreatment. The contents of Δ9-THC and CBN in the extracted oil samples were 9.58 mg/kg and 52.45 mg/kg, respectively. Compared with the oil extracted by Soxhlet extraction (SE), the oil extracted by this experimental method was of better quality and similar in fatty acid composition. [ABSTRACT FROM AUTHOR]

[Display omitted] • The mechanism of layered porous g - C 3 N 4 is different from layered nonporous g - C 3 N 4. • H 2 production rate decreased with increasing the electronegativity of halide ions. • RhB degradation increased with increasing the electronegativity of halide ions. • The most active species for F-doped g-C 3 N 4 are leaved holes. • The active species for pristine and Cl/Br-doped g-C 3 N 4 are superoxide radicals. Halogen doping is an effective approach to regulate the electronic structure and improve photocatalytic properties of g-C 3 N 4. Here, a salt-assisted approach was employed to prepare layered porous halogen-doped g-C 3 N 4. The effects of halogen electronegativity and pore morphology were discussed. Highly electronegative F-doped g-C 3 N 4 with smaller pore size and higher surface area displayed the enhanced absorption property on reactants. The H 2 production rate decreased and the RhB degradation significantly increased with increasing the electronegativity of layered porous g-C 3 N 4 , which was significantly different from the conventional halogen-doped g-C 3 N 4 prepared with halogenated acid and monolayer g-C 3 N 4. The decreased H 2 evolution can be ascribed to the strong adsorption property, and the strong interactions between halide ions and H+ were difficult to be disassociated. Additionally, the RhB degradation performance of halogen-doped g-C 3 N 4 significantly increased with increasing the electronegativity. The most active species that dominated the RhB degradation of F-doped g-C 3 N 4 are leaved holes (h+), which are totally different from that of the pristine g-C 3 N 4 and Cl/Br-doped g-C 3 N 4 (superoxide radicals,·O 2 –). This work helps us to well understand the role and importance of electronegativity and pore morphology on the H 2 generation and RhB degradation properties of layered porous g-C 3 N 4. [ABSTRACT FROM AUTHOR]

Oils are susceptible to oxidation, so encapsulation of them with small molecule gels and proteins through dynamic high-pressure microfluidization is an effective method of protection. In this study, conjugated linoleic acid (CLA)-rich oil-in-water oleogel emulsions (CLA-Og/W) was prepared by dynamic high-pressure microfluidization. By results, when dynamic high-pressure microfluidization pressure was 80 MPa, zeta potential of CLA-Og/W was −38 mV, the droplet size decreased to 91.3 nm. The surface roughness of the CLA-Og/W reduced to a minimum of 2.75 nm at 80 MPa. The surface tension decreased to 38.36 mN/m. The rheological properties showed that the microfluidized CLA-Og/W had favorable viscoelasticity and increased apparent viscosity. In addition, the fatty acid composition of CLA-Og/W did not change significantly compared to CLA-safflower seed oil. After 14 d of storage at 60 °C, the CLA content of CLA-Og/W was 40.19%. Consequently, CLA-Og/W treated with dynamic high-pressure microfluidization had more stable physicochemical properties and better retention of CLA. • Oleogel emulsion was prepared by dynamic high-pressure microfluidization. • Minimum droplet size obtained at 80 MPa processing pressure. • After 14 d of storage at 60 °C, the conjugated linoleic acid was 40.19%. [ABSTRACT FROM AUTHOR]