Exploring a simple, on-demanding method of manipulating ionic conduction of ionic liquids with large amplitudes is a challenging task. Here, a reversible ion-conducting switch was obtained based on photoswitchable sol−gel transitions. The device was successfully applied in an electronic circuit to switch it on/off. The ion gel was prepared by directly mixing following individual components: azobenzene (Azo), poly(Nisopropylacrylamide) (PNIPAm), and. The framework of this gel structure was particularly designed as an analogue to the physical mode of control theory: sensor/amplification/action. Light-induced isomerization of Azo acts as the light sensor to trigger the macroscopic sol−gel transition of PNIPAm assemblies. Such transition works as the amplification, which significantly affects the ionic movements, resulting in high-amplitude switching behavior. A photoswitchable ionic conductive device was demonstrated as action in this paper. Under UV irradiation, the sol-like state of Azo/PNIPAm/[C 2 mim][NTf 2 ] provided a higher ion conduction (around 1 mS/cm) while being exposed to visible light, and a lower ion conduction (0.04 mS/cm) was observed in the gel state. This photoswitchable ion conductivity device was integrated to a well-designed logic gate to switch circuits on or off. This confirms the possible practical application of the sol−gel device, which outputs stable and detectable electrical signals.The research here demonstrates a simple but effective strategy to control the ionic movements, which can be applied in optoelectronic devices. The principle can be used to design different types of molecular optoelectronic switches.

The porous PLA foams potential for tissue engineering usage are prepared by a modified solvent casting/particulate leaching method with different crystallinity. Since in typical method the porogens are solved in the solution and flow with the polymers during the casting and the crystallinity behavior of PLA chains in the limited space cannot be tracked, in this work the processing is modified by diffusing the PLA solution into a steady salt stack. With a thermal treatment before leaching while maintaining the stable structure of the porogens stack, the crystallinity of porous foams is made possible to control. The characterizations indicate the crystallization of porous foams is in a manner of lower crystallibility than the bulk materials. Pores and caves of around 250µm size are obtained in samples with different crystallinity. The macro-structures are not much impaired by the crystallization nevertheless the morphological effect of the heating process is still obvious.

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This paper addresses fixed-time trajectory tracking for a dual-arm free-floating space robot (FFSR) with the large initial errors and bounded uncertainty. A wrist-based trajectory planning method is improved by fixed-time stability to fast eliminate the error caused by singularity. Then, a novel low-chattering and global-nonsingular fixed-time terminal sliding mode control strategy is studied by state approaching angle and switching sliding mode; the practical fixed-reachable Lyapunov stability analysis is presented for a mechanical control system. In the end, the proposed trajectory planning method and controller are combined to improve the tracking accuracy of end-effector to the nanoscale. Simulation results validate the effectiveness of the proposed methodologies.