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The static and dynamic corrosion experimental platforms of supercritical fluid reactor were used for the static and dynamic corrosion test of Q235, 304, 316L, P91, N80 and 3Cr13 in the supercritical water pseudo-critical region (22.5 MPa, 375.6 ℃) and gas-like region (22.5 MPa, 407.6 ℃) for 72 h. The results show that the dynamic corrosion rate of materials in supercritical water environment is significantly higher than the static corrosion rate, and the flow accelerates the corrosion process, in which 304 is increased by more than 4 times; the strengthening effect of dynamic conditions on corrosion mass gain is weakened with the decrease of corrosion resistance. The factors that exacerbate corrosion under dynamic conditions are: flow shear force accelerates the movement of the corrosive medium in the supercritical fluid to the substrate surface, promoting the corrosion chemical reaction; the flow shear force scours the material surface, promotes the dissolution of Fe on the material surface, and accelerates the corrosion chemical reaction; the erosion effect of shear force promotes the detachment of corrosion product crystals during the formation process of the wall, accelerating the corrosion process.

Soft tissue integration is one major difficulty in the wide applications of metal materials in soft tissue-related areas. The inevitable inflammatory response and subsequent fibrous reaction toward the metal implant is one key response for metal implant-soft tissue integration. It is of great importance to modulate this inflammatory-fibrous response, which is mainly mediated by the multidirectional interaction between fibroblasts and macrophages. In this study, macrophages are induced to generate M1 and M2 macrophage immune microenvironments. Their cytokine profiles have been proven to have potentially multi-regulatory effects on fibroblasts. The multi-reparative effects of soft tissue cells (human gingival fibroblasts) cultured on metal material (titanium alloy disks) in M1 and M2 immune microenvironments are then dissected. Fibroblasts in the M1 immune microenvironment tend to aggravate the inflammatory response in a pro-inflammatory positive feedback loop, while M2 immune microenvironment enhances multiple functions of fibroblasts in soft tissue integration, including soft tissue regeneration, cell adhesion on materials, and contraction to immobilize soft tissue. Enlighted by the close interaction between macrophages and fibroblasts, we propose the concept of an “inflammatory-fibrous complex” to disclose possible methods of precisely and effectively modulating inflammatory and fibrous responses, thus advancing the development of metal soft tissue materials.

Improving the corrosion protection level of metal materials for ocean engineering equipment is of great significance for the improvement of the abilities to explore ocean resources. The macro corrosion mechanism of such metal materials have been investigated extensively, but the micro corrosion mechanism is still unclear. In this paper, the research progress of molecular dynamics simulation of metal materials for ocean engineering equipment was summarized. Besides, the potential function and model describing the reaction between metal and solution/gas, and the influence of different factors on metal corrosion were introduced respectively. Finally, in order to provide a reference for the study of more efficient and inexpensive corrosion protection methods, the problems existing in the current calculation and simulation of metal material corrosion were also analyzed and the prospects were put forward.

With the development of electronic information technology and people's pursuit of convenient life, smart flexible wearable devices have attracted the attention of many scholars. In the development of smart wearable devices, flexible conductive materials play a vital role. As the most basic flexible conductive textile material, conductive yarn is widely used in smart wearable products. However, most traditional textile materials are insulating materials and cannot directly form conductive yarns and smart wearable products. The preparation methods and application research progress of metal-based conductive yarns, carbon-based conductive yarns, and conductive polymer-based conductive yarns, as well as the application research progress in wearable strain sensors, wearable supercapacitors, wearable electric heating devices and other aspects were introduced. The problems that need to be solved in the research of conductive yarns in recent years were analyzed, mainly including improving the conductivity, flexibility and environmental stability of conductive yarns. In addition, in view of the convenience, comfort, washing durability, and sensitivity required by smart wearable devices, it was proposed that the sensitivity, durability of flexible conductive yarn and the combination of textile materials and conductive materials have become the main development of wearable flexibles smart product.

This research article presents metal material cleaner by applied high frequency ultrasonics is one choice to utilize the sound energy. This method is to transfer ultrasonics energy to the cleaning unit.In this research, the IC# SG3525A is used to generate frequency at 28 kHz. The IC#TLP250 is a optocoupler which is used to interface between the output of the IC#SG3525A and the input of the isolated drive circuit. The high frequency circuit is used to drive the gate of Power MOSFETs#IRFP450 in half-bridge Inverter circuit. Then, the output signal is transferred to high frequency transformer to step up the voltage. After that, the receiving A/C 350 watt drives the seven ultrasonic transducers in order to transfer electric energy to mechanical vibrating energy by the frequency of ultrasonics. In addition, there is a timekeeper to control the work duration. This metal material cleaner by ultrasonic can increase the ability of cleaning for the huge material parts and it can be used in another cleaning industry.