To improve the magnetorheological (MR) properties and dispersion stability of the carbonyl iron (CI) particles, bidisperse magnetorheological (BMR) fluids consisting of magnetic micron-sized CI and nanoparticles dual-coated with gelatin and multi-walled carbon nanotubes (MWCNTs) were synthesized for the first time. Gelatin was used as a grafting agent to improve the stability of bidisperse magnetic particles and restrict the oxidation of nanoparticles (Fe 3 O 4 ). And a dense network composed of MWCNTs on the surface of gelatin-coated bidisperse particles was fabricated based on the self-assembly of MWCNTs to produce considerably rough surfaces. The influence of functional dual-coated layer on rheological performance such as shear stress and yield stress behavior was investigated by a rotational rheometer upon various magnetic field applications. Additionally, the dispersion stability was measured through sedimentation tests. The results showed that CI-Fe 3 O 4 -Gelatin-MWCNTs (CI-Fe 3 O 4 -G-NT) magnetic microspheres possessed enhanced MR properties compared with those from CI-Fe 3 O 4 -Gelatin (CI-Fe 3 O 4 -G) microspheres, while the dispersion stability of CI-Fe 3 O 4 -G-NT microspheres was still maintained.

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relationship model of environmental regulations, green innovation, environmental dynamism and intelligent upgrade is established. Based on the data of Chinese manufacturing listed companies in the process of intelligent upgrade, this article quantitatively analyzes the relationship between environmental regulations, green innovation, environmental dynamism and intelligent upgrading. This article quantitatively studies the role of environmental regulations in promoting intelligent upgrading. It proves the mediating role of green innovation between environmental regulations and intelligent transformation and upgrading. The mediating role of environmental dynamics between green innovation and intelligent upgrading is discussed. The article strives to provide theoretical guidance and practical inspiration for the intelligent upgrading of manufacturing enterprises. The possible marginal contributions of this paper are as follows: Firstly, the impact mechanism of environmental regulations on the intelligent upgrade of manufacturing enterprises is clarified. By constructing a mechanism model of environmental regulations on the intelligent upgrading of manufacturing enterprises, the direct and indirect effects of environmental regulations on the intelligent upgrading of manufacturing enterprises are analyzed. Secondly, it reveals the important role of green innovation in environmental regulations and intelligent upgrading of manufacturing enterprises. By analyzing the relationship between green innovation and the intelligent upgrading of manufacturing enterprises, green innovation and environmental regulations, it verifies the intermediary role of green innovation in environmental regulations and intelligent upgrading of manufacturing enterprises. Thirdly, clarify the regulatory role of environmental dynamism between green innovation and the intelligent upgrading of manufacturing enterprises. This article analyzes the relationship between environmental dynamism and green innovation and the intelligent upgrade of manufacturing companies, and empirically examines the regulatory role of environmental dynamism between green innovation and the intelligent upgrade of manufacturing companies. The rest of this article is organized as follows. "Literature review" section summarizes and reviews relevant important literature. "Research hypotheses" presents research hypotheses among environmental regulations, green innovation, environmental dynamism, and intelligent upgrades. "Materials and method" section presents the research design and method of this paper. "Empirical results and discussion" section verifies the research hypothesis, gives the research results, and discusses the results. "Conclusion and implications" section draws conclusions and theoretical implications.

Bionic artificial muscle made from chitosan gel is an emerging type of the ionic electro active polymer with advantages of large deformation, low cost and environmental protection etc, which leads to a research focus and wide application in the fields of bionic engineering and intelligence material recently. In this paper, effects and improvement mechanisms of the direct casting and genipin cross-linking processes on response speed properties of the chitosan gel artificial muscle (CGAM) were mainly studied. Based on in-depth analysis of the CGAM response mechanism, a platform was built for testing the response performance of the CGAM, then its equivalent circuit and mathematical models were also established. Furthermore, control experiments were carried out to test and analyze several performances of the CGAM on response speed, electrical conductivity, mechanical properties and microstructure with different control variables. The experimental results illustrated that the CGAM assembled by direct casting enabled its electric actuating membrane and non-metallic electrode membrane tightly attached together with low contact resistance, which dramatically promoted the electrical conductivity of the CGAM resulting in nearly doubled response speed. Besides, different concentrations of genipin were adopted to cross-link the CGAM actuating membranes, and then it was found that the response speed of the uncross-linked CGAM was fast in the initial stage, but as time increased, it declined rapidly with poor steadiness. While there was no obvious decrease over time on the response speed of the CGAM cross-linked with low genipin concentration. Namely, its stability was getting better and better. In addition, the response speed of the CGAM cross-linked with low concentration of genipin was roughly the same as uncross-linked CGAM, which was quicker than that of high concentration. In this work, its internal mechanisms, feasible assembly technique and green modification method were provided to further explore the practical applications significantly.

In this study, a novel flexible conductive sodium alginate/chitosan (SA/CS) foam with double-network structure based on dual-coated magnetic particles (MPs) was prepared by a biological crosslinking process of natural biopolymers. The structural characterization, response deformation and magnetic-field-dependent electric performance for different foams were investigated, and they were significantly dependent on the mass ratio of SA/CS, the contents of glycerol and MPs. By increasing SA and CS, the electrostatic interactions of double-network enhanced, leading to an increase in its binding force with the MPs, so the magnetic-responsive performance was strongly improved. Meanwhile, the resistance displayed a remarkable variation under the magnetic fields. For instance, the resistance of the sample with a mass ratio of 3:3 decreased with the magnetic flux densities (0.10-0.40 T) and it ranged from 14.8-6.83 kΩ, which reduced by about 53.9%. Moreover, the periodic measurements were applied so as to verify its recoverability and repeatability. Furthermore, a possible mechanism was provided to explain the magnetic-responsive behavior of the samples. Because of the superior magnetic controllability and preeminent mechanical performance, the conductive porous foam is promising in the fields of artificial electric skins, soft sensors and actuators.

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Biomimetic is the field of engineering in which biological creatures and their functions are investigated and are used as the basis for the design and manufacturing of machines. Ionic Polymer Metal Composite (IPMC) is a smart material which has demonstrated a meaningful bending and tip force after the application of a low voltage. It is light-weighted, flexible, easily actuated, multi-directional applicable and requires simple manufacturing. Resultantly, IPMC has attracted scientists and researchers to analyze it further and consider it for any industrial and biomimetic applications. Presently, the research on IPMC is bi-directional oriented. A few groups of researchers are busy to find out the causes for the weaknesses of the material and to find out any remedy for them. The second class of scientists is exploring new areas of applications where IPMC material can be used. Although, the application zone of IPMC is ranging from micropumps diaphragms to surgical holding devices, this paper provides an overview of the IPMC application in biomimetic and biomedical field.