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In recent years, aerogels have received more and more attention from researchers due to their properties such as low density, high porosity, high specific surface area and low thermal conductivity. Polysaccharide-based aerogel is a solid porous nanomaterial with three-dimensional network structure prepared by using polysaccharide as the precursor material and transforming the liquid phase in the gel with gas phase through a drying method. In addition to the characteristics of traditional aerogel materials, polysaccharide-based aerogels also have the advantages of non-toxicity, easy availability of raw materials, biocompatibility and biodegradability. This article summarizes the preparation methods of polysaccharide-based aerogels, and reviews the properties and applications of different types of polysaccharide-based aerogels prepared with different precursor materials, so as to provide a reference for the research and application of polysaccharide-based aerogel materials in food packaging.

This study investigates the impact of Environmental, Social, and Governance (ESG) performance on the green technological innovation (GTI) of Chinese A-share-listed companies, using data from 2009 to 2022. The findings indicate that strong ESG performance significantly enhances GTI, with this effect being more pronounced in state-owned firms and non-high-tech sectors, demonstrating heterogeneity across firm types. Mechanism analysis reveals that ESG performance facilitates GTI by mitigating financing constraints and boosting R&D investments. Moreover, the study identifies a non-linear relationship, wherein the effect of ESG on GTI varies with firm size and environmental regulation intensity, as confirmed through a threshold model. This study not only deepens the theoretical framework linking corporate ESG performance with GTI but also uncovers the practical mechanisms through which ESG performance drives GTI, providing both practical insights and theoretical foundations for governments to formulate corporate green transition policies. [ABSTRACT FROM AUTHOR]

Metasurfaces have the capability to boost the generation of distinct colors by improving the interaction between surface materials and photons. We present a straightforward and polarization-tunable aluminum nitride metasurface. This metasurface enables the display and concealment of the composition pattern and exhibits color switching by modifying the polarization state of the incident light. We further explore the impact of different substrates on metasurface performance. The results indicate that the full width at half maximum of the reflectance curves increases with the increase of the refractive index between the nanostructures and the substrate material, which leads to a broader dispersion of the structural colors in the spectrum. Moreover, the sizes of the nanostructures can be gradually reduced for the substrate with a high refractive index. These findings not only offer polarization-tunable structural color metasurfaces but also provide essential insights in selecting nanostructure and substrate materials, which will help in the design of nanostructures for such metasurfaces. [ABSTRACT FROM AUTHOR]

Aiming at the functional requirements of mobile mechanisms with multiple modes，a design scheme based on single-loop kinematic chains is proposed.Firstly，according to the single-loop freedom formula，the conditions satisfying the single-loop and can be active are determined，and the combination relationships among the order of the constrained screw system，the number of bars，the number of kinematic pairs and the degree of freedom of the single-loop kinematic chains are obtained.Secondly，based on the screw theory，the geometric conditions of the axis of kinematic pairs under different constrained screw orders are obtained by using the virtual work principle.Taking the R and P pairs as the design units，all the possible combinations of the single-loop kinematic chains under different degrees of freedom are enumerated，and then the constructed single-loop kinematic chains are used as the body or branch to construct a kind of mobile mechanisms with multiple modes.Finally，the steps of type synthesis of mobile mechanisms with multiple modes and some design cases are given，which verifies the feasibility and practicability of the proposed design theory and design method.

Aromatic amino acids (AAA), including phenylalanine (Phe), tyrosine (Tyr), and tryptophan (Trp), are essential building blocks of proteins, however, they have been implicated in multiple amino acid metabolism diseases, such as phenylketonuria, tyrosinemia, and glutaric acidemia type I. Dietary therapy is indispensable for patients with AAA metabolism disorder. This review briefly describes the pathogenesis and nutritional treatment guidelines of several AAA metabolic diseases. The techniques of protein hydrolysis and AAA removal from raw protein materials are very important in the development of special medical foods (SMFs) for above diseases. Therefore, existing protein hydrolysis techniques including enzymatic and microbial hydrolysis are reviewed, and the widely applied AAA removing methods including ultrafiltration and adsorption by active carbon and resin are also discussed. In addition, the application of several promising materials to remove AAA with better selectivity, such as molecular imprinting polymer, cyclodextrin, TiO2 and carbohydrate-based reverse micelle are prospected. This review may promote the development of SMFs for AAA metabolic diseases, and provide potential directions for processing technology improvement. [ABSTRACT FROM AUTHOR]

Fractional order systems have a wider range of applications. Hidden attractors are a peculiar phenomenon in nonlinear systems. In this paper, we construct a fractional-order chaotic system with hidden attractors based on the Sprott C system. According to the Adomain decomposition method, we numerically simulate from several algorithms and study the dynamic characteristics of the system through bifurcation diagram, phase diagram, spectral entropy, and C0 complexity. The results of spectral entropy and C0 complexity simulations show that the system is highly complex. In order to apply such research results to engineering practice, for such fractional-order chaotic systems with hidden attractors, we design a controller to synchronize according to the finite-time stability theory. The simulation results show that the synchronization time is short and the robustness is stable. This paper lays the foundation for the study of fractional order systems with hidden attractors.

Memristor is a kind of nonlinear resistance with memory function, which is a typical nonlinear circuit component. In this paper, the problem of a simple chaotic circuit based on the memristor was studied. We constructed a new simple circuit of multiple memorizing components, summarized the mathematical model and found seven types of chaotic attractors without reference to classical circuits that substituted memristors for elements in the original circuit. Traditional methods of dynamic analysis are used to analyze the equilibrium point and stability of the system. Furthermore, we analyzed the dynamical behavior with the varying coefficient of the system specifically. In order to reduce the deviation from the actual physical circuit system as much as possible so as to facilitate the follow-up research of scholars, we solved the problem of Hopf bifurcation in this system under the condition of time delay through the use of the canonical form and Hopf bifurcation theory. Theoretical analysis and simulation results show that there existed the state transition in seven chaotic attractors of system and the bifurcation was stable when we changed the parameter τ slightly. As a small unit circuit, this paper lays a foundation for the research and control of large-scale system with memorizing components. [ABSTRACT FROM AUTHOR]