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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]

In order to improve the accuracy of forecasting crude oil prices, a new crude oil price forecasting method is introduced in the paper that is a combination of the FNN model and the stochastic time effective function—namely, the WT-FNN model. The FNN model keeps track of the historical values of crude oil prices and predicts future crude oil prices, and the stochastic time effective function gives greater weight to recent information and smaller weight to old information, thus making the prediction of crude oil prices more reasonable. We selected the daily data of Brent crude oil prices from 4 January 2000 to 30 September 2021 as research objects and then used the WT-FNN model to train and predict the research objects. By comparing it to the benchmark model, we found that the predictive effect of the WT-FNN model was better than the FNN model and the no-change model. The results also passed a robustness test. [ABSTRACT FROM AUTHOR]

• Rice bran protein-tannic acid emulsions were treated with ultrasound. • Ultrasonic treatment improved microstructure and properties of emulsions. • The best emulsion properties were obtained at an ultrasonic power of 400 W. Rice bran protein (RBP)-tannic acid (TA) complex was prepared and the RBP-TA emulsions were subjected to ultrasonic treatment with different powers. Ultrasonic treatment has a positive effect on improving the properties of RBP-TA emulsion. This study investigated the influence of different ultrasonic power levels on the physicochemical properties, microstructure, rheological properties, and stability of emulsions containing RBP-TA. Under the ultrasonic treatment of 400 W, the particle size, zeta potential, and adsorbed protein content of the RBP-TA emulsion were 146.86 nm, −20.7 eV, and 61.91%, respectively. At this time, the emulsion had the best emulsifying properties, apparent viscosity, energy storage modulus and loss modulus. In addition, the POV and TBARS values of RBP-TA emulsions were 6.12 and 7.60 mmol/kg, respectively. The thermal, salt ion, pH and oxidative stability of the emulsions were investigated, and it was shown that ultrasonic treatment was effective in improving the stability of RBP-TA emulsions. [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]

In this paper, free vibration and transmission properties of single and composite thin annular plate (TAP) structures are presented by wave approach. The propagation matrix, continuity matrix and reflection matrix are introduced to carry out the analysis. Using the wave approach, natural frequencies of single and composite TAP are calculated theoretically. The results obtained by this method agree well with those calculated by the classical Bessel and Hankel methods. Additionally, transfer matrix is introduced and combined with the boundary conditions to obtain the transmission behaviors of composite multilayer TAP. To thoroughly understand the composite TAP, the influences of thickness, density ratio and radius ratio on natural frequencies are investigated. This study provides very useful information for transverse vibration suppression of TAP structure. [ABSTRACT FROM AUTHOR]

• Single atom catalyst with Co-N 4 coordination has been precisely synthesized. • The interconnected 2D network can alleviate the formation of Li-dendrites. • Co-N 4 center suppress the shuttle effect and reduce the reaction energy barrier. • The correlation between the Co-N 4 sites and catalytic activity is deciphered. • The batteries exhibit superior electrochemical performance. Developing electrocatalyst to ameliorate the shuttling effect of lithium polysulfides (LiPSs), sluggish sulfur redox reaction kinetics and the rampant dendrite growth is of paramount importance for lithium-sulfur (Li-S) batteries. Yet still, the utilization of the most mainstream traditional metal electrocatalytic nanoparticles is far below expectation. Herein, we engineer an exclusive single-atom catalyst with planar Co-N 4 coupling of nitrogen-doped graphene mesh (SA-Co/NGM) to achieve exceptional atom utilization efficiency for catalytic conversion of LiPSs. High surface area and ultra-thin two-dimensional texture can not only accommodate high concentration monodispersed lithiophilic atomic Co sites, but also guarantee homogenize high-flux Li ion transport, alleviating the formation of Li-dendrites. Critically, the maximized exposure of Co-N 4 as a regulator in sulfur electrochemistry can conspicuously suppress the shuttle effect and accelerate bidirectional sulfur redox kinetics via electron delocalization, as demonstrated by a judicious combination of electro-kinetic analysis, in situ spectroscopy and density functional theory (DFT) computations. As expected, the batteries based on a SA-Co/NGM modified separator achieve an ultrahigh rate capability, exceptionally long cycle life and a distinguished favorable areal capacity under high sulfur loading. This work provides a rational design of single-atom catalysts for kinetics-boosted electrocatalysis towards long-lasting Li-S batteries. [ABSTRACT FROM AUTHOR]

Radial vibration of the circular plate is presented using wave propagation approach and classical method containing Bessel solution and Hankel solution for calculating the natural frequency theoretically. In cylindrical coordinate system, in order to obtain natural frequency, propagation and reflection matrices are deduced at the boundaries of free-free, fixed-fixed, and fixed-free using wave propagation approach. Furthermore, radial phononic crystal is constructed by connecting two materials periodically for the analysis of band phenomenon. Also, Finite Element Simulation (FEM) is adopted to verify the theoretical results. Finally, the radial and piezoelectric effects on the band are also discussed. [ABSTRACT FROM AUTHOR]

As for studying the sub-harmonic and super-harmonic periodic motions, eigenvalue dynamics and period-doubling bifurcation tree of the nonlinear rotor system, an implicit discrete mapping method is applied to a nonlinear sliding bearing–rotor system. The nonlinear term of the rotor system is triggered by the oil film forces of the sliding bearing at both ends. In order to accurately reveal the dynamic characteristics of the system, in this paper, a thirteen-parameter polynomial oil film force model is proposed. It considers the effects of displacement and velocity on the oil film force. And, the discrete mapping method used in this paper is a semi-analytical tool for solving equations with high precision. Consequently, continuous eigenvalue diagrams and bifurcation trees of periodic solutions from Period-1 to Period-4 motions of the nonlinear rotor system are obtained. For verification, numerical simulations are completed. Numerical and semi-analytical results are compared in time–history displacement, velocity and trajectories. Furthermore, the active feedback controller is carried out to improve the stability of the system. • An implicit discrete mapping method is applied to a nonlinear sliding bearing–rotor system. • The nonlinear term of the rotor system is triggered by the oil film forces of the sliding bearing at both ends. And, the oil film force model is proposed as a thirteen-parameter polynomial in this paper. • Continuous eigenvalue diagrams and bifurcation trees of periodic solutions from Period-1 to Period-4 motions of the nonlinear rotor system are obtained. [ABSTRACT FROM AUTHOR]

• A three-dimensional Ni,Co-embedded CNT-coated N-doped hollow porous carbon (Ni/Co-CNT/NHPC) cathode has been designed and prepared for lithium-sulfur battery. • The Ni/Co-CNT/NHPC-S cathode possesses a high specific capacity of 1352 mA h g-1 and an excellent cycle stability at 1 C with low capacity decay of 0.094% per cycle over 500 cycles. • The mechanism of suppressing the shuttle effect on the cathode materials is discussed by analyzing adsorption experiments and density functional theory（DFT）calculation. Lithium-sulfur (Li-S) batteries have attracted great attentions due to their high specific capacity. However, the poor cycle stability caused by polysulfide shuttles, volume expansion and formation of lithium dendrites limit their practical applications. In the present work, to tackle the poor stability and unstable rate capability, a MOF-doping strategy is developed to construct a hollow porous carbon framework，which consists of Ni, Co particles and CNT on a N-doped shell surface (Ni/Co-CNT/NHPC). This hollow framework increases the load of S, slows down the volume changes, and can physically entrap soluble polysulfide. It is found that the CNT-coated network structure is beneficial for optimizing the conductivity and wettability of the material, which accelerates the reaction kinetics. Moreover, synergistic effect of abundant defects and Ni, Co nanoparticles strengthens the chemisorption of polysulfides, which suppresses the shuttle effect. As a consequence, the Ni/Co-CNT/NHPC-S cathode harvests a high specific capacity (1352 mA h g-1), and shows an excellent cycling stability at 1 C with low capacity decay of 0.094% over 500 cycles. [ABSTRACT FROM AUTHOR]

Islet transplantation has great potential for curing type 1 diabetes; however, long-term islet survival using conventional immunosuppression remains elusive. We present a novel strategy for inducing long-lasting islet graft survival in diabetic NOD mice in the absence of posttransplant immunosuppression by initial treatment with antilymphocyte serum (ALS) followed by coadministration of donor pancreatic lymph node cells (PLNCs). When treated with ALS/PLNC, diabetic NOD mice become normoglycemic and tolerated minor antigen-disparate islet grafts for >100 days and syngeneic islet grafts indefinitely. Donor T-cells are required for graft prolongation, and tolerant hosts have long-term donor T-cell chimerism. Strikingly, host autoreactive T-cells from mice with long-surviving islet grafts predominantly produce interleukin-4, whereas autoreactive T-cells from mice that rejected their islet grafts predominantly produce interferon-gamma. We thus demonstrate a clinically relevant approach for ablation of recurrent autoimmunity in islet transplantation, involving donor lymphocyte-driven alteration of pathogenic autoreactive T-cells. [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]

• 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]

Although the fully grouted tension anchorage system (T-anchorage system) has been widely used in the field of anchoring of earthen heritage sites, it has always suffered from the failure of the bolt–slurry interface debonding and the strong attenuation of the shear stress of the bolt–slurry interface along the embedment length. In this article, a new type of fully grouted tension–compression composite anchorage system (TC-anchorage system) is proposed, which is made up of a pressure bearing system with the same diameter of the anchor hole at the end of the tension bolt. The in situ anchorage, pull-out test and interfacial stress–strain monitoring were carried out for the T-anchorage systems and the TC-anchorage systems. This was based on the preliminary analysis and comparison of the structure and working mechanism of the two anchorage systems. The test results show that: the average ultimate load of the TC-anchorage system is about 40% higher than that of the T-anchorage system. TC-anchorage systems have the characteristics of small elastic deformation and large plastic deformation. The strain at the bolt–slurry interface varies progressively along the embedded length with the increase of load in a positive skewness–bimodal–negative skewness curve. The working mechanism of TC-anchorage systems includes three progressive stages: bolt–slurry interface debonding, conical slurry formation and slurry extrusion. The research conclusion provides a reference for the application of TC-anchorage systems in the protection and reinforcement of earthen heritage sites. [ABSTRACT FROM AUTHOR]

In the field of oil refining, the presence of excessive residual phosphorus in crude oil can significantly impact its quality, thereby emphasizing the necessity for compact and convenient testing equipment. This study primarily focuses on developing of self-powered biosensor (SPB) using immobilizing Choline Oxidase with a photoactive ternary nanocomposite complex (CHOx-BiOI-rGO-Fe 3 O 4 NPs-ITO) as the anode and utilizing a Pt electrode as the cathode. The successful preparation of the ternary composite photoelectrode for the anode was confirmed through a range of characterization techniques, including X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), Transmission electron microscopy (TEM), Scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), N 2 absorption/desorption, Dynamic light scattering (DLS), and Ultraviolet–visible diffuse reflection spectrometer (UV–vis DRS). The electrochemical and photoelectrochemical properties were assessed using an electrochemical workstation, revealing a significant enhancement photoelectrical responsiveness attributed to the formation of heterojunction structures. The SPB exhibited a remarkable linear relationship between the instantaneous photocurrent and phosphatidylcholine (PC) concentration, with a regression equation of I (μA) = 39.62071C (mM) + 3.47271. The linear range covered a concentration range of 0.01–10 mM, and the detection limit (S/N = 3) was determined to be 0.008 mM. It demonstrated excellent reproducibility and storage stability, positioning it a promising alternative to High-performance liquid chromatography (HPLC) for accurate quantification of PC content in rhodotorula glutinis oil. The standard recovery PC content ranged from 98.48% to 103.53%, with a relative standard deviation (RSD) ranging from 1.4% to 2.4%. This research presents a convenient and precise detection device that has the potential to address the issue of lagging detection in the oil refining process. [Display omitted] [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]

This paper aims to investigate the seismic behavior and failure mechanism of novel type of blind bolted concrete-filled steel tubular (CFST) composite frames under seismic loading. The composite frames are composed of square or circular CFST columns and steel-concrete composite beams with steel-bars truss deck (SBTD); the steel beams and the CFST columns are assembled by blind bolts and end plates. The failure modes, hysteretic behavior, strength and rigidity degradation, ductility and energy-dissipating performance of all specimens were analyzed and discussed. The influence of composite action of the floor slab on the performance of blind bolted CFST composite frames were also explored under seismic loading. The experimental results showed that the blind bolted CFST composite frames with the SBTD concrete slabs exhibited good hysteretic behavior, large ductility and high energy dissipation. The stiffness and strength of the frame increased greatly with the presence of the SBTD concrete slab. These test studies could promote the engineering design and application of the blind bolted CFST composite frames. [ABSTRACT FROM AUTHOR]

Karst rocky desertification (KRD) has become one of the most serious ecological and environmental problems in karst areas. At present, mapping KRD with a high accuracy and on a large scale is still a difficult problem in the control of KRD. In this study, a random forest (RF) based on maximum information coefficient and correlation coefficient feature selection is proposed to predict KRD. Nine predictors stood out as feature factors to estimate KRD. Rock exposure was the most important predictor, followed by fractional vegetation cover for the prediction of KRD processes. The kappa and classification accuracy indexes were to evaluate the performance of the model. We recorded overall accuracy rate and kappa index values of 94.7% and 0.92 for the testing datasets respectively. The RF model was then used to predict the KRD in 2001, 2011, 2016, and 2020, and it was found that the KRD in the study area has exhibited a positive trend of improvement. Therefore, the use of multisource remote sensing data combined with the RF model can obtain better prediction results of KRD, thereby providing a new idea for large-scale estimation of the KRD in peak-cluster depression. [ABSTRACT FROM AUTHOR]

The optimal allocation of educational resources has been a hot issue, and exploring the accessibility of educational facilities in poor mountainous areas helps to reasonably plan the layout of educational facilities and promote the balanced development of education. Taking the rocky desertification area in Yunnan, Guangxi, and Guizhou (YGGRD) as the study area, based on the POI data of educational facilities in the YGGRD in 2000, 2010 and 2019, this study explored the evolution of the accessibility of educational facilities in the YGGRD through raster accessibility. And the influencing factors were analyzed by the ordinary least square method (OLS) and geographically weighted regression model (GWR), and evaluated the model through cross validation. The results show that the overall accessibility of educational facilities improved significantly from 2000 to 2019. Educational facilities mainly have good accessibility and average accessibility. Poor accessibility areas are concentrated in the interprovincial border regions, and the boundary effect is significant. County accessibility, population density and rural per capita disposable income have a great impact on the accessibility of educational facilities in the YGGRD. It is suggested to strengthen the construction of educational facilities in the interprovincial border regions, relocate and integrate villages, and improve the education quality of township schools to improve the supply of rural educational resources. [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, the coupling effect between the crankshaft torsional vibration and the low speed diesel engine block vibration is investigated. Using finite element method (FEM), a model of low speed diesel engine is established to study the vibration response. The mode results of FEM agree very well with the test. The additional torques acting on the low-speed diesel engine caused by torsional vibration are discussed in detail. The vibration response of the low-speed diesel engine considering the effect of torsional vibration is studied using FEM simulation. By analyzing the effect of torsional vibration, the results demonstrate that the crankshaft torsional vibrations have important effects on the engine block vibration. The results from this study can provide useful theoretical guidance to predict vibration of low-speed diesel engine. [ABSTRACT FROM AUTHOR]

• A fracture failure of a marine diesel engine timing gear is investigated in detail. • Both experimental and numerical investigations are performed. • Influence of associated structures is considered while analyzing the fracture. • Two models, one is with inclusion and the other is non-inclusion, are constructed. • Results indicate the fracture is a fatigue fracture and is caused by the inclusion. In this paper, a fracture failure of a marine diesel engine timing gear in a chemical tanker was investigated in detail using both experimental analysis and numerical analysis. The experimental analysis includes macroscopical inspection, Scanning Electron Microscope analysis, Energy Dispersive Spectroscopy analysis, metallographic investigation and mechanical property investigation. The numerical analysis includes torsional vibration analysis and finite element method (FEM) simulations. In the torsional vibration analysis, the coupling influence of the associated structures on the timing gear system was taken into account, not only analyzing the fault gear itself. In the FEM simulations, two models, one is with inclusion and the other is non-inclusion, were constructed. Both investigations indicate that the fracture is a fatigue fracture and the initial cracks are caused by the inclusion. Further investigation should pay attention to finding a way to overcome the problem of fatigue fracture. [ABSTRACT FROM AUTHOR]

Planetary gears are one part of the whole transmission chain, and the dynamics and vibration characteristics of them are strongly coupled with external rotors. In this paper, to demonstrate the interaction between multistage planetary gears and external rotors as well as investigate the lateral-torsional coupling characteristics of them, a coupling model of a two-stage planetary gear rotor system is proposed. In such a model, the two-stage planetary gear subsystem is established as a lumped-parameter model and the external rotor subsystem is established as a finite element model. The vibration mode distribution properties and lateral-torsional coupling characteristics are both analyzed by modal strain energy. Three different conditions are considered: uncoupled, partially coupled, and fully coupled. The results indicate that the coupling among multiple subsystems and the lateral-torsional coupling mainly exist in the low-mode region. Natural frequencies dominated by the two-stage planetary gear subsystem are sensitive to coupled conditions, whereas natural frequencies dominated by the input rotor subsystem are remarkably insensitive to coupled conditions. Furthermore, the natural frequency of the first torsional mode can be obtained only in the fully coupled condition. Experiments are implemented to obtain natural frequencies, and the experiment results validate the numerical results. [ABSTRACT FROM AUTHOR]

A novel image analysis method for improving the reading performance of the radio frequency identification (RFID) system is proposed by arranging the geometric distribution of multiple tags reasonably based on flood fill and direct linear transformation (DLT) in this paper. An image collecting system is projected to collect the image of RFID tags, and an online detection system is designed to measure the reading distance. The proposed system has good performance of instantaneity and robustness, in which tags could be identified rapidly with the tray turning. The 2-D distribution images of tags are processed using the flood-fill technique. Furthermore, the 3-D distribution images of tags are analyzed based on DLT. Subsequently, a tag network is established, in which a tag is described as a node. Finally, support vector machine is introduced to predict the reading distance and corresponding distribution for a given number of tags after training the measured reading distance of RFID tags under various geometric distributions. The results show that the optimal geometric distribution of tags could be obtained by analyzing the images of tags and the predicted reading distance of tags. This method can improve the dynamic performance of multiple tags in the RFID system effectively. [ABSTRACT FROM PUBLISHER]

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]

In the measurement of real radio frequency identification (RFID) system, due to the relative and absolute systematic errors, biased estimators do happen in the practical measurement, which are difficult to be analysed. In order to get effective biased estimators, the linear and nonlinear functions in the measurement of RFID tags are taken as a paradigm to study the equivalence between the bias‐corrected estimators and biased estimators. The measurement curve of optimum distribution angles of multiple tags is analysed in particular based on Fisher information determinant (FID), which could be used to evaluate the optimum performance of multiple RFID tags system. The results demonstrate the bias‐corrected estimators of the single tag's reading distance and multiple tags' measurement curve of optimum distribution angles in RFID system could be obtained by calculating the corresponding biased estimators. Particularly, the biased estimator of multiple tags' measurement curve of optimum distribution angles reaches the CRB when and only when the bias‐corrected estimator reaches its corresponding CRB. Finally, the general expression of the biased CRB case in UHF RFID measurement is obtained. This study could be used as an evaluation tool for the measurement uncertainty limit of biased estimators. [ABSTRACT FROM AUTHOR]

• We developed an integrated model to quantify biodiversity by habitat quality. • Cultivated land mainly transfers into woodland, with some of construction land. • Biodiversity habitat quality under ecological protection scenarios is best. • The biodiversity of the upper and lower reaches in 2030 shows trend of improvement. The temporal and spatial dynamics of biodiversity and its future trends are of great significance for maintaining biodiversity pattern and ensuring regional ecological security in the Nanliu River Basin of Beibu Gulf. At present, most studies are concerned with the assessment of biodiversity in historical period, but few studies focused on the prediction of biodiversity under several scenarios in future years, and the history and future spatial simulation of habitat quality has not been carried out. Therefore, the establishment of biodiversity simulation studies under different scenarios in the future plays a crucial role in the sustainable development of regional social economy. This study takes Nanliu River Basin, which only flows into the sea in the Beibu Gulf, as the research object. Based on land use data and social and economic data interpreted from remote sensing data in 2000, 2010 and 2020, Conversion of Land Use and its Effects at Small Region Extent (CLUE-S) model was used to simulate and predict land use patterns for ecological protection scenarios, natural growth scenarios and food security scenarios in 2030. The Integrated Valuation of Ecosystem Service and Tradeoff (InVEST) model was used to evaluate the biodiversity of different scenarios in the past and future and discuss the habitat quality and degradation degree of biodiversity in the watershed. Results were presented as follows. In 2000–2020, an increasing trend of construction land, shrub land and water area was found in the Nanliu River basin of Beibu Gulf. The largest increase was observed in construction land, and the largest decrease was noted in cultivated land and woodland. The best habitat quality will be under the ecological protection scenario in 2030. The biodiversity in the upstream and downstream of the three scenarios showed varying degrees of improvement, and the midstream exhibited a degradation trend. The research results of this paper can make up for the vacancy of biodiversity habitat evaluation system in Nanliu River Basin at home and abroad, and have important theoretical and practical significance for promoting ecological protection and ecological planning of watershed. [ABSTRACT FROM AUTHOR]

The establishment of appropriate analytical methods to authenticate the geographic origin of poultry meat independent of paper record becomes especially important nowadays. In this study, data were analyzed in terms of both the contents of two stable isotopes (C and N) and 12 mineral elements of chicken samples from four provinces to trace their geographical origin. The results showed that classification of chicken was improved by combining both types of data, as compared to that using the mineral element data alone. The present study demonstrates that it is possible to indicate the poultry origin by applying stable isotope and multi-element analysis, which is an effective tool to trace the geographic origin of poultry. [ABSTRACT FROM AUTHOR]

This paper presents a method for structural modifications for achieving desired eigenstructures based on receptances, by adding multiple mass-spring systems to some locations of the primary system. This method has the benefit that not only neither analytical nor modal models are needed, but also the original mass and stiffness of the primary system are maintained. Moreover, when a complex structure or machine is designed for some special functions so that its inner structure is not allowed to be modified, it is an effective way in practice to achieve desired dynamical performance resulted from adding several external simple substructures. The theory is presented in this paper, which is suitable for linear undamped systems. Numerical experiment is set up, and the results of the modifications are compared with the method proposed by Braun and Ram. Both theoretical derivation and numerical results demonstrate the effectiveness of this method. [ABSTRACT FROM AUTHOR]