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Wrapping paper has an irreplaceable role in the food industry, but the high hydrophilicity of cellulose-based wrapping paper limits its application. Here, we aim to develop a fluorine-free and stable method for preparing the superhydrophobic cellulose-based paper using KH570-modified-n-TiO2 and ε-polylysine (ε-PL) to construct a superhydrophobic surface by layer-by-layer self-assembly. The paper modified by (ε-PL/KH570-modified-n-TiO2)4 multilayers has superhydrophobic and self-cleaning properties after heat treatment. The water contact angle reaches up to 152.8° and the antibacterial rate is close to 100%. The high barrier properties to water vapor better prolong the shelf life of cherries. Therefore, the (ε-PL/KH570-modified-n-TiO2)4 multilayers modified paper can provide a new idea for food preservation. The advantage of the double-layer assembly is that even if the superhydrophobic layer of the wrapper is worn away and lost, the remaining ε-PL is still able to act as a bacterial inhibitor, ensuring that the food is not perishable. [ABSTRACT FROM AUTHOR]

In order to improve the low-temperature cracking resistance and durability of high-modulus asphalt mixture, this article proposes the use of Trinidad Lake Asphalt (TLA) and polyester fibre complex methods to obtain high-modulus asphalt mixture, based on indoor accelerated load, low bending temperature, freeze-thaw splitting and APA fatigue test to study the influence of TLA content on permanent deformation resistance performance, water stability, low-temperature crack resistance and fatigue resistance of high-modulus asphalt mixtures. Meanwhile, it reveals the mechanism of the TLA and polyester fibre composite modified on high-modulus asphalt mixture and recommends the best solution of high-modulus asphalt complex is 30% TLA + 3‰ polyester fibre. [ABSTRACT FROM AUTHOR]

Aronia melanocarpaberries are abundant in polyphenolic compounds. After juice production, the pomace of pressed berries still contains a substantial amount of polyphenolic compounds. For efficient utilization ofA. melanocarpaberries and the enhancement of polyphenolic compound yields inAronia melanocarpapomace (AMP), total phenolics (TP) and total flavonoids (TF) from AMP were extracted, using ultrasound-assisted aqueous two-phase system (UAE-ATPS) extraction method. First, the influences of ammonium sulfate concentration, ethanol–water ratio, ultrasonic time, and ultrasonic power on TP and TF yields were investigated. On this basis, process variables such as ammonium sulfate concentration (0.30–0.35 g mL−1), ethanol–water ratio (0.6–0.8), ultrasonic time (40–60 min), and ultrasonic power (175–225 W) were further optimized by implementing Box–Benhnken design with response surface methodology. The experimental results showed that optimal extraction conditions of TP from AMP were as follows: ammonium sulfate concentration of 0.324 g mL−1, ethanol–water ratio of 0.69, ultrasonic time of 52 min, and ultrasonic power of 200 W. Meanwhile, ammonium sulfate concentration of 0.320 g mL−1, ethanol–water ratio of 0.71, ultrasonic time of 50 min, and ultrasonic power of 200 W were determined as optimum extraction conditions of TF in AMP. Experimental validation was performed, where TP and TF yields reached 68.15 ± 1.04 and 11.67 ± 0.63 mg g−1, respectively. Close agreement was found between experimental and predicted values. Overall, the present results demonstrated that ultrasound-assisted aqueous two-phase system extraction method was successfully used to extract total phenolics and flavonoids inA. melanocarpapomace. [ABSTRACT FROM PUBLISHER]

A method to analyze the time-delay stability of stochastic power system with wind power connection is proposed in this paper. First, the reduced-order electromagnetic model of double fed induction generator (DFIG) suitable for time-delay stability analysis is established. Meanwhile, the mechanical power of DFIG is selected as the stochastic excitation, and the mechanical system model of the stochastic wind power is established according to the Wiener process. Second, the state equations of the power system are derived based on the stochastic differential equation (SDE). Then, the Lyapunov–Krasovskii functional considering the stochastic characteristic of wind power is constructed, and the weak infinitesimal generating operators of the functional are calculated according to thedifferential formula. On this basis, the time-delay stability criterion for the power system under stochastic excitations is formulated. Finally, the variation of system time-delay stability upper bound with the stochastic excitation intensity of wind power, excitation magnification, and damping coefficient is analyzed using generalized eigenvalue problem (GEVP). Simulation results of IEEE 16-machine 68-bus system demonstrate that the time-delay stability upper bound of the power system decreases when the excitation magnification coefficient of synchronous generator increases, and it increases when the damping coefficient of synchronous generator increases. However, the effect of stochastic excitation intensity of wind power on the time-delay upper bound is more complex, and there is a distinct concave area in the change trend. [ABSTRACT FROM AUTHOR]

A new method based on fault chains and the Markov process for analyzing time-delay power system stability is proposed in this article. First, reasonable fault chains are formed using the fault chain generation method based on network power flow. Second, by combining the fault chains and Markov processes, a class of Lyapunov–Krasovskii functionals considering the Markov jump is established. Free weighting items constructed with the Markov process transfer rate matrix and Newton–Leibniz formula, respectively, are then introduced to the weak infinitesimal operators in the Lyapunov–Krasovskii functional. Meanwhile, to lower the conservativeness of the method, the whole time-varying time-delay interval has been divided into two subintervals. Finally, the time-delay upper bound that the power system can bear in the case of cascading faults is calculated by means of the generalized eigenvalue problem. The efficiency and feasibility of the proposed method in solving the maximum time delay in the case of cascading faults have been validated by the dynamic time-domain simulation results. Comparative results with other methods show the proposed method has low conservativeness. [ABSTRACT FROM AUTHOR]

A kind of launching platform driven by two permanent magnet synchronous motor (PMSM) motors which is used to launch kinetic load to hit the target, always faces strong parameter uncertainties and strong external disturbance such as the air current impulsion, which would degrade their tracking accuracy greatly. In this paper, an adaptive robust nonlinear controller is proposed for high-accuracy motion control of the launching platform, in which the adaption law is designed to estimate the unknown coupling coefficients of torque disturbance and feed-forward cancellation technique is used to compensate the coupling torque disturbance and some other constant disturbances. In addition, a nonlinear robust feedback term is designed to inhibit the influence of the parameter estimation error and the other model uncertainty to stabilise the closed-loop system. Considering that some system states are immeasurable due to cost-reduction, volume/weight limitations and structure restriction or heavy measurement noise is usually associated with the measurements, which may also deteriorate the achievable performance of full-state feedback controllers; a high-order sliding-mode observer is used to estimate the unmeasured system states, and it is synthesised with the adaptive robust controller via feed-forward cancellation method. The intermediary virtual control law and the final control law are derived by integrating the backstepping method. Furthermore, the controller theoretically guarantees a prescribed tracking transient performance and final tracking accuracy while achieving asymptotic tracking performance in the presence of parametric uncertainties only, which is very important for high-accuracy tracking control of launching platform. Extensive comparative experimental results are obtained to verify the high performance nature of the proposed control strategy. [ABSTRACT FROM AUTHOR]

The use of gravel–sand mulch is a traditional water-conservation technique in the semi-arid Loess Plateau of North-western China. In this study, we investigated the 16-year effects of this mulch on soil physicochemical properties (total organic C, N and P; bulk density; Ca, Cu, Fe, Mg, Mn and Zn; soil texture; pH), microbial biomass C, N and P and enzymatic activities (peroxidase, dehydrogenase, invertase,β-glucosidase, alkaline phosphomonoesterase and urease) in a field trial in China's Gaolan County. We examined how these parameters changed after 7, 11 and 16 years of mulching. After 16 years, soil bulk density and sand content increased significantly. Soil Ca and Cu contents did not change significantly during the study period, but Fe, Mg, Mn and Zn contents all decreased significantly after 16 years. The total N increased significantly after 11 years, but total C and N both decreased dramatically and significantly after 16 years (by 22% and 13%, respectively, compared to the control). The mulch significantly increased microbial biomass C (by 29% after 11 years), with similar results for N and P, but these positive effects were lost after 16 years. Enzyme activities revealed changes in the soil microbial community over time; the mulch increased enzyme activities until 11 years, followed by a significant decrease that suggested degradation of soil quality after long-term mulching. The positive effects of the mulch (increasing soil temperature) could explain the high microbial biomass and enzyme activities after 11 years. However, long-term increases in soil bulk density and sand content (caused by mixing of the mulch layer with the surface soil) and a lack of inputs of organic matter (caused by the barrier created by the mulch layer) led to degradation of the soil after 16 years. [ABSTRACT FROM AUTHOR]

A new mononuclear eddy identification method based on sea level anomaly (SLA) data was developed and described in this study. To solve the multinuclear eddy problem, we employed two strategies to split the eddies into individual eddies: the closest angle and the closest distance strategies. Each strategy produces an eddy with only one SLA extremum. The splitting procedure is based on these strategies. No artificial threshold is needed with these strategies, but a threshold for strategy choice is required. The splitting strategies are adaptable to various identification methods. The examples indicate that the splitting procedure clearly captures the mixing of eddies. When applied to the global ocean, the proposed method obtained similar and more reasonable results. The splitting procedure is linear without any iteration; thus, it is very fast (the time complexity isO(N), whereNis the number of multinuclear eddy pixels). In statistics, the proposed method can identify approximately 30–40% more eddies than the multinuclear eddy method. [ABSTRACT FROM AUTHOR]

This study was performed to explore the function and mechanism of Dvl3 in RA-FLS by exosome intervention. The expression pattern of Dvl3 was examined by IHC, WB, and qPCR. Modified exosomes obtained from culturing supernatant of RA-FLS infected with Dvl3 over expression (OE) lentivirus were administrated to the target RA-FLS. The ability of survival, migration, and the production of inflammatory factor influenced by exosomal Dvl3 were detected by CKK8 kits, Tunel, migration test, qPCR, and enzyme-linked immunosorbent assay (ELISA) respectively; Flow cytometry analysis was conducted to explorer the inflammatory moderate role of exosomes on CD4+ T cells. The possible downstream pathways of Dvl3 were screened by qPCR and WB and verified by double luciferase reporter experiment. The expression level of Dvl3 was significantly increased in RA and CIA. Exosomes from the OE group could significantly promote cell proliferation activity, migration/invasion ability. The augment of TNF-α, IL-1β, IL-17, and IL-21 was observed in exosomal Dvl3-OE group. Th1 and Th17 cells polarisation and cytokines related were both enhanced by Exosomal Dvl3. Over expression of Dvl3 was accompanied by the significant increase of β-catenin and RhoA activities. This study discovered the high expression of Dvl3 of exosomes derived from RA patients which may possessed the ability to promote phenotypic transformation of RA-FLS through Wnt pathway. [ABSTRACT FROM AUTHOR]

This study makes a significant contribution to the field of groundwater potential mapping (GWPM) by exploring the application of ensemble learning models (ELMs), specifically boosting ensemble models (BEMs), which have not been fully utilized in GWPM. By employing six ELMs (random forest, AdaBoost, XGBoost, CatBoost, GBDT and LightGBM), along with Tree-structured Parzen Estimator in Luoning County, China, this study identifies key indicators (topographic position index, distance to rivers and topographic wetness index) and demonstrates the superior model performance of XGBoost compared to other ELMs. Additionally, correlation analysis confirms the accuracy of XGBoost in predicting relationships between important indicators and groundwater potentials. Finally, the findings provide valuable insights for sustainable groundwater management strategies in Luoning County and emphasize the need for further exploration of ELMs, development of comprehensive performance evaluation and indicator systems, reduction of the inconsistencies between indicators and predication results and practical research to support future sustainable groundwater management. [ABSTRACT FROM AUTHOR]

To explore the effect of doxycycline on vasculogenic mimicry (VM) formation and the potential mechanism in human pterygium fibroblasts in order to find novel targets for pterygium therapy. First, we demonstrate the existence of VM in 73 pterygium specimens by CD31 and periodic acid Schiff (PAS) dual staining. Then we used cell counting kit-8, clone formation assay and flow cytometry to prove the inhibitory effect of doxycycline on cell proliferation and apoptosis. The VM formation was evaluated through wound healing assay, cell transwell assay and three-dimensional cell culture combined with PAS staining. Finally, we used Western blot to testify the correlation of the VM and the factors in protein level preliminarily. Our results showed that VM existed in human pterygium specimens exactly. Otherwise, in human pterygium fibroblasts, doxycycline induced a dose-dependent inhibitory effect on cell proliferation and apoptosis induction. Besides, doxycycline significantly suppressed vasculogenic mimicry tube formation, cell migration and invasion. Furthermore, doxycycline impaired the expression of MMP-9, MMP-2 and VEGF which may related to pterygium VM formation. Doxycycline decelerated pterygium progression might be through inhibiting VM formation according to the downregulation of MMP-9, MMP-2 and VEGF, which may provide the basis of further studies involving doxycycline for pterygium treatment. [ABSTRACT FROM AUTHOR]

Four new coordination polymers, [Cd(3-TPTP)Cl]2(3-HTPTP = 4′-(3-tetrazolylphenyl)2,2′:6′2′′-terpyridine,1),{[Cd(3-TPTP)(pBDC)0.5]∙4H2O}n(pH2BDC = 1,4-benzenedicarboxylic acid,2), {[Mn(3-TPTP)(mBDC)0.5]∙5H2O}n(mH2BDC = 1,3-benzenedicarboxylic acid,3), and [Pb(3-TPTP)(H2O)2]∙OH (4), were obtained. Compounds1–3are composed of binuclear [M2(3-TPTP)2] ring as building unit. In1, the binuclear rings pack into a 3-D supramolecular framework via various hydrogen bonds. In2and3, the binuclear rings are connected bymBDC2−andpBDC2−, respectively, resulting in two types of 1-D chains. In4, the mononuclear [Pb(3-TPTP)] units are connected by Pb⋯N weak interactions, giving a chiral 1-D coordination chain, which is further connected by O–H⋯N interaction to form a chiral 3-D supramolecular framework. The phase purity of1–4and luminescence properties of1,2, and4were also investigated. [ABSTRACT FROM PUBLISHER]

A day dispatch strategy for the integrated system (IS) of wind/photovoltaic/pumped-storage/gas-turbine-power/energy-storage plant is proposed in this paper based on the time-frequency scales of power of wind/photovoltaic (PWP). Based on the day-ahead dispatch strategy, the day dispatch optimization model of the IS is first established, and then according to the patulous short-time prediction (PSP) and ultra-short-time prediction (UP) of PWP, the day rolling and real-time scheduling strategies are put forward based on the time-frequency scales of PWP. Finally, the cone programming method is applied to optimize the day dispatch schedule. Simulation results show that the proposed strategy can compensate for the error in the day-ahead dispatch strategy based on short-time prediction (SP) of PWP. Thus, as an important supplement to the day-ahead dispatch strategy, this method is proved to be an effective solution to the power fluctuation problem in large-scale wind/photovoltaic integration, realizing a smooth power output, as well as guaranteeing the economical, efficient, and environmentally friendly operation of the system. [ABSTRACT FROM AUTHOR]

Due to the impossibility for the equilibrium-point eigenvalue method to reflect the oscillation characteristic of the fault system correctly, and the difficulty in choosing the window length using a trajectory eigenvalue method, a model-trajectory method is proposed to analyze the eigenvalue of a fault system. First, the system is equated by the mutual factor after fault clearance. Then the branch current and power of the post-fault system is calculated by the branch current of the original and the fault component network, respectively. Furthermore, the equivalent model of the system is built and linearized at each measuring point. By combining the linearized model with the actual disturbed trajectory, the time series of the eigenvalue of the fault system is calculated. Simulation results of 2-generator system and a 16-generator system illustrate that the model-trajectory method is able to describe the time-varying oscillation characteristic of a fault system effectively and accurately. [ABSTRACT FROM PUBLISHER]

In view of the reduced low-frequency oscillation damping effect caused by inaccurate modeling of the power system due to various uncertainties, a Youla parameterization robust control strategy considering system uncertainties is proposed in this article. First, the uncertainties of the measurement error and parameter estimation are described by the perturbation matrix, and the convex polytopic model is utilized to describe uncertainties caused by variation of the operating point. Then, by solving theH2/H∞inequalities, the Youla parameterization matrix is gained. Finally, the output error of the actual system to the nominal system is introduced to the output feedback control link via the Youla parameterization matrix. Thus, tracking control of the output error can be realized, as well asH2/H∞robust control of the system. Simulation results show that the proposed method is immune to internal and external uncertainties. Compared with control methods without considering uncertainties, the proposed method is capable of damping low-frequency oscillation faster and more effectively with better robust performance. [ABSTRACT FROM AUTHOR]