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Highly PL carbon quantum dots (CQDs) were successfully prepared from C60 by introducing CTAB and H2O2 in aqueous NaOH under hydrothermal conditions. The CQDs displayed a nanoparticle aggregation-induced emission enhancement (NP-AIEE).

The self-assembly of two-dimensional (2D) graphene sheets into three-dimensional (3D) structures is an effective approach to fabricate graphene-based hierarchical architectures for practical applications. Here we report an easy and environmentally friendly method to fabricate a graphene-based multifunctional hydrogel using a biocompatible polysaccharide as both a stabilizer and a physical cross-linking agent. The as-prepared hydrogel is highly stable in a variety of harsh conditions such as strong acid, strong alkali, high ion strength solution, and organic solvent. Moreover, it shows excellent dye adsorption and antibacterial capability, and has been successfully used for miniature-scale water purification. The present work provides a new insight for the self-assembly of functionalized graphene with biomolecules, offering an alternative way to fabricate multifunctional materials for a wide range of applications.

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The contour accuracy of XY table directly driven by two linear motors was influenced by the complicated reel-time contour error model of free-form curves, uncertainty external disturbance and dynamic matching between X axis and Y axis. To establish XY table model that easily calculated and suitable for free-form curves, real-time contour error estimate method was adopted. In order to reduce uncertainty external disturbance and dynamic matching between X axis and Y axis, the iterative learning cross-coupled controller (ILCCC) was designed for current compensation on X axis and Y axis. Simulation results show that the control scheme can enhance the robustness of the system, and effectively improve the XY table of contour precision.

The high penetration of doubly-fed induction generators (DFIGs) entails a change in dynamics and operational characteristics of the power system, thus this paper investigates the small signal stability of the large-scale wind farm with DFIGs. The GE 1.5MW DFIG is modeled in power system analysis software package (PSASP), and a large-scale wind farm with DFIGs is established. Then, the two-area test system with four generators is applied to assess the effect of the large wind farm on power system inter-area oscillatory mode in which the penetration and the installation site of the wind farm are considered. Finally, the simulation results indicate that abundant penetration of DFIG-based wind power will improve the inter-area oscillatory, and the integration of wind farms with DFIGs in the receiving area makes the inter-area mode highly damped.

Electrician machine practice is an important engineering practice teaching element in the cultivation plan of undergraduate student of electricity. The task- driven teaching method is adopted in order to improve the quality of practice teaching, and to cultivate the ability of practice and creativity in the electrician machine practice. This paper discusses the mission design and implementation process which based on constructivist task-driven teaching method in the teaching of electrician machine practice, and points out several questions which should be noticed in the practice. The practice approves the application of task- driven teaching method in electrician machine practice can improve the teaching quality through excavating the student’s practice and creativity ability and cultivate the capability of independent thinking ,exploration and reclamation more effectively.