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This study investigated the influence of heat treatment on the interaction of large yellow croaker (Pseudosciaena crocea)roe protein isolate (pcRPI) with curcumin (Cur), and heated pcRPI (HpcRPI)-Cur and pcRPI-Cur complexes were also prepared. Fourier transform infrared spectroscopy, fluorescence spectroscopy, and surface hydrophobicity analysis indicated that pcRPI and HpcRPI bind to Cur mainly by hydrogen bonds, van der Waals interactions, and hydrophobic interactions, and compared with pcRPI, HpcRPI showed better binding effects with Cur. Molecular docking analysis also evaluated the binding site and the forces between vitellogenin, vitellogenin B and C in pcRPI and Cur. Furthermore, HpcRPI-Cur could form gels induced by glucono-δ-lactone (GDL), while pcRPI-Cur-GDL exhibited a fluid state. The HpcRPI-Cur-GDL gels showed great protective effects on Cur in the resistant gastrointestinal environment. These results indicated that heat treatment will improve the application of pcRPI as a functional material in the food field.

Different sources of proteins have various ways for facilitating the gelation process of surimi matrices, leading to the diverse combined effects with transglutaminase (TG). In this study, the effects of two plant proteins, soy protein isolate (SPI) and pea protein isolate (PPI), and two animal non-muscle proteins, egg white protein (EWP) and whey protein isolate (WPI), with TG addition on the gel properties of clam Meretrix meretrix(MM) surimi gels were investigated, and the mechanisms were explored. In the presence of TG, the exogenous protein addition significantly improved (p< 0.05) the gelation process of the MM surimi. The best improvements were obtained with the combination of EWP, where the gel strength, cooking loss and water holding capacity were enhanced by 113.08%, 67.89%, and 26.30%, respectively. The addition of SPI showed a relatively weak enhancement compared to EWP incorporation, followed by the addition of PPI and WPI. The results of optical microscopy, differential scanning calorimetry, and chemical forces demonstrated that TG preferentially promoted plant proteins to form self-aggregation in the surimi system, and SPI generated more polymers than PPI. In contrast, the interpenetration of animal proteins and MM myofibrillar proteins was improved by TG. EWP formed a double cross-linking network within the MM protein network, while WPI acted as a binder to promote protein-protein interactions. This research could provide novel insights for developing MM resources and establish a theoretical foundation for the use of composite exogenous protein additives to enhance the gel properties of MM surimi products.

The results of the electrochemical impedance spectroscopy and Tafel measurements indicate that the reduction process from triiodide to iodide at the counter electrode surface is determined by the kinetic-controlled and diffusion-limited processes.

Positive materials for nickel/metal hydride battery, nickel hydroxide doped by different metal ions were synthesized by coprecipitation, and subsequent hydrothermal treatment and anion exchange method. The structure of the samples was analyzed by XRD test, and the electrochemical performances were studied by galvanostatic charge-discharge, cyclic voltammetry and impedance tests. The obtained electrode material shows mainly β-Ni (OH)2 structure when only doping Zn2+, while α-Ni (OH)2 structure was obtained by only doping Al3+ or co-doping Al3+ and Zn2+. Ni (OH)2 co-doped Al3+ and Zn2+ had fine cyclic stability, high number of exchanged electrons per nickel atom (the maximum is 1.93), small charge-transfer and proton-diffusion resistances.

This paper researched the displacement amplification and hysteresis of parallel four-bar amplification mechanism using piezo actuator. Firstly, the displacement amplification was analyzed by employing the material bending theory. Theory and finite element model (FEM) proved that the amplification ratio of parallel four-bar mechanism is only related to the position of driving point and the guiding beam displacement is linear with the driving point input when it is fixed. Then the Preisach model was employed to model the hysteresis of guiding beam and performed to control the output displacement of the mechanism. Experiments proved that the model can effectively improve the output displacement accurate of the guiding beam and can realize random sequence output displacement using the Preisach interpolation surface.

TiO2 colloids prepared by sol-gel method were autoclaved and then deposited onto a transparent conducting oxide substrate by screen-printing. The TiO2 films electrode was characterized by XRD, SEM, AFM and Alpha-Step profilometer and then sensitized by zinc phthalocyanine (ZnPc), 2,9,16,23-tetracarboxy zinc phthalocyanine (ZnTCPc) and ZnTCPc/lauric acid respectively. Photocurrent density (I) and photovoltage (V) of the electrode were measured with the solar simulator. The ZnTCPc-sensitized electrode was found the best performance with the short-circuit photocurrent density (Isc) 16.66 3A/cm2, the open-circuit photovoltage (Voc) 277.9 mV and the fill factor (FF) 0.39. And the ZnPc-sensitized electrode was found the worst performance with Voc 114.2 mV, Isc 2.26 3A/cm2 and FF 0.31. It was also found that lauric acid promoted Voc of the the ZnTCPc sensitized system.

The nonstationary transition status of the motor start-up phase creates great threat against the stable operation of the flexible manipulator system. This article investigates the electromechanical coupling dynamics and vibration response characteristics for a flexible manipulator of an alternating current servomotor-driven linear positioning platform with considering the start-up dynamic characteristics of the motor. Based on the constructed global electromechanical coupling effect and the Lagrange–Maxwell equations, the dynamic model of the whole system is established. The electromechanical coupling vibration mechanism of the flexible manipulator is obtained by analyzing the multiphysical process and multiparameter coupling phenomenon of the whole system. The result demonstrates that the nonstationary transition status of the motor initialization phase is mainly manifested during the disturbance of the three-phase stator current. As the speed of the linear positioning platform increases, the current disturbance, arousing the change of the servo driving force of the linear positioning platform, has dominant frequency shift and frequency amplitude decrease. Then, the vibration response of the flexible manipulator is markedly affected and the variation of the high-order modes vibration response is more obvious. The analysis result is significant for improving the dynamic performance of the motor-driven flexible robot manipulator system.