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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]

In this study, the structure and flavor characteristics of soybean meal hydrolysates-reducing sugars Maillard reaction products (MRPs) were evaluated. Sugars added to the soybean meal enzymatic hydrolysates increased the Maillard reactivity in the following order: hexose < pentose. Results indicated that the intrinsic fluorescence intensity of MRPs increased, whereas the absorption peak intensity of the infrared spectrum changed significantly. Molecular weight analysis results showed that the MRPs were mainly distributed between 128-500 and 500–1000 Da. Furthermore, the bitter amino acid content (9.29 mg/g) and umami amino acid content (3.60 mg/g) were relatively high in ribose-MRPs. The umami, richness and bitterness values of pentose-MRPs were higher than those of hexose-MRPs. Moreover, the analysis of volatile substances showed that the ribose-MRPs presented a stronger caramel aroma, nutty flavor, and grilled meat flavor. • Reducing sugar types affected the structure and flavor of Maillard reaction products. • Soybean meal enzymatic hydrolysates were prepared by two-step enzymolysis. • Maillard reaction products were mainly distributed between 128-500 and 500–1000 Da. • Ribose-Maillard reaction products showed a stronger flavor characteristic. [ABSTRACT FROM AUTHOR]

[Display omitted] • A double carbon encapsulated porous composite with compact interface was designed. • The P-Si@rGO@C electrode exhibited inspiring rate-capability and long-cycling life. • The storage mechanism was explored via reaction kinetics, Ex-situ tests, and DFT. • A Li x Si prelithiation suspension was provided to enhance the ICE of the full cell. Developing high-performance composites with fast charging and superior cycle life is paramount for lithium-ion batteries (LIBs). Herein, we synthesized a double-shell carbon-coated porous structure composite with a compact surface (P-Si@rGO@C) using low-cost commercial micron-sized silicon (Si) instead of nanoscale silicon. Results reveal that the unique P-Si@rGO@C features high adaptability to volume expansion, accelerates electron/ion transmission rate, and forms a stable solid electrolyte interphase (SEI) film. This phenomenon arises from the synergistic effect of abundant internal voids and an external double-layer carbon shell with a dense surface. Specifically, the P-Si@rGO@C anode exhibits a high initial coulombic efficiency (ICE) (88.0 %), impressive rate-capability (612.1 mAh/g at 2C), and exceptional long-term cyclability (972.2 mAh/g over 500 cycles at 0.5C). Further kinetic studies elucidate the diffusion-capacitance hybrid energy storage mechanism and reveal an improved Li+ diffusion coefficient (from 3.47 × 10-11 to 2.85 × 10-9 cm2 s-1). Ex-situ characterization confirms the crystal phase change of micron-sized Si and the formation of a stable LiF-rich SEI. Theoretical calculations support these findings by demonstrating an enhancement in the adsorption ability of Si to Li+ (from -0.89 to -0.97 eV) and a reduction in the energy migration barrier (from 0.35 to 0.18 eV). Additionally, practical Li x Si powder is shown to increase the ICE of full cells from 67.4 % to 87.9 %. Furthermore, a pouch cell utilizing the prelithiated P-Si@rGO@C anode paired with LiNi 1/3 Co 1/3 Mn 1/3 O 2 (NCM111) cathode delivers a high initial reversible capacity of 7.2 mAh and 76.8 % capacity retention after 100 cycles. This work provides insights into the application of commercial silicon-aluminum alloy powder in the anode of high-energy LIBs. [ABSTRACT FROM AUTHOR]

The fabricated VS 4 /Ni 3 S 2 /NF NBs was prepared by self-templated strategy, with exposed abundant hetero-interfaces and high active disulfide (S 2 2-) sites. The density functional theory revealed the reversible conversion catalysis mechanism of bridge S 2 2- during HER process, jointly promoting the HER performance. [Display omitted] • A novel VS 4 nanoparticle decorated Ni 3 S 2 nanobelt array was synthesized via one-step organic ligand-assisted solvothermal method. • The abundant disulfide (S 2 2-) moieties grafted on the hetero-interfaces of VS 4 /Ni 3 S 2 led to strong electronic interaction and promote the chemisorption of H-containing intermediates. • The density functional theory reveals the reversible conversion catalysis mechanism about disulfide (S 2 2-) sites during HER process. • The findings provide fresh insights for developing potential polysulfides as high-performance hydrogen-evolving electrocatalysts from water splitting. Elaborate and rational design of cost-effective and high-efficiency non-noble metal electrocatalysts for pushing forward the sustainable hydrogen fuel production is of great significance. Herein, a novel VS 4 nanoparticle decorated Ni 3 S 2 nanobelt array in-situ grown on nickel foam (VS 4 /Ni 3 S 2 /NF NBs) was prepared by a self-templated synthesis strategy. Benefitting from the unique nanobelt array structure, abundant highly active bridge S 2 2- sites and strong electronic interaction between VS 4 and Ni 3 S 2 on the heterointerface, the integrated VS 4 /Ni 3 S 2 /NF NBs exhibited excellent electrocatalytic hydrogen evolution activity and robust stability. The density functional theory (DFT) further revealed the reversible conversion catalysis mechanism of bridging S 2 2- sites in VS 4 /Ni 3 S 2 /NF NBs during HER process. Notably, bidentate bridging S S bonds as the predominant catalytically active centers can spontaneously open once H adsorbed its surface, leading to the aggregation of negative charges on S atoms and thus facilitating the generation of H* intermediates, and spontaneously close when H* desorption is going to form H 2. Our work provides fresh insights for developing potential polysulfides as high-performance hydrogen-evolving electrocatalysts for prospective clean energy production from water splitting. [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]

In this paper, an exact analytical solution is proposed to investigate the free in-plane vibration of sector plates. The highly complex and coupled differential equations of in-plane vibration motion are decoupled by invoking Helmholtz decomposition. The method of separation of variables is used to solve the resulting uncoupled Helmholtz equations. Applying the boundary conditions at both radial edges, the compatible eigenvalue problems for sector plates are obtained. Then, applying the boundary conditions at inner and outer circumferential edges, the corresponding characteristic equations can be solved to obtain the natural frequencies and the associated mode shapes. The results from the proposed method agree very well with the results from the available literature and the FEM. Significant influence of the boundary conditions and the geometric parameters on the free in-plane vibration characteristics of sector plates is investigated and addressed. The superficial frequency veering "aberration" between neighboring modes is discussed and found in fact to be an eigenvalue crossing phenomenon. It is proved that for a sector plate, only with simply supported radial edges, there exists an exact analytical solution. The proposed exact analytical solution can provide not only the detailed characteristics of the free in-plane vibration of sector plates but also the benchmark for further study. [ABSTRACT FROM AUTHOR]

Neuroprotection refers to the relative preservation of neuronal structure and function. Neuroprotective agents refer to substances that are capable of preserving brain function and structure. Currently, there are no neuroprotective agents available that can effectively relieve the progression of Parkinson’s disease. In this work, five novel 4-aminopyridine derivatives, including three amides and two ureas, were designed, synthesized, and evaluated using the rat PC12 mice pheochromocytoma cell line as an in vitro model. As well as human Rho kinase inhibitory experiment was performed. Among them, compound 3 , which exhibited high cell viability, low cytotoxicity and good efficacy of inhibition on α-synuclein, oxidation, inflammation and Rho kinase, was profound as potential agents for Parkinson’s disease (PD). [ABSTRACT FROM AUTHOR]

This paper proposes a unified semi-analytical method for the free in-plane and out-of-plane vibrations of arbitrarily shaped plates with clamped edges. The method is derived using boundary conformal mapping (BCM). The BCM is first proposed here to overcome the mathematical difficulty in describing the clamped boundary conditions of complex or/and irregular shaped plates. Elliptical, rectangular and horseshoe plates with clamped edges are studied to demonstrate the proposed method. After that, another two groups of arbitrarily shaped plates including three polygonal plates and three curve-edged plates are studied. The efficiency of the proposed method is checked through a convergence study. Results from the proposed method agree well with the available results in the literature and with finite element results. All the case studies demonstrate that the proposed method is versatile and gives good accuracy for both the in-plane and out-of-plane vibrations of arbitrarily shaped plates with clamped edges. New results from the proposed method can serve as benchmarks for further study on the vibration of plates, especially of irregular shaped plates. • Free in-plane and out-of-plane vibration solutions for clamped plates are proposed. • Solutions are semi-analytical, generalized and apply to arbitrarily shaped plates. • Boundary conformal mapping (BCM) is introduced to obtain the solutions. • BCM overcomes mathematical difficulty in describing irregular shaped boundary conditions. • BCM method is versatile and has excellent accuracy. [ABSTRACT FROM AUTHOR]