7In this study, we report a single electrodeposition process to fabricate multilayered 8 chitosan/layered double hydroxides (LDHs) hybrid hydrogel for stimuli responsive protein release. 9LDHs nanoplatelets with regular hexagonal shape were synthesized by hydrothermal method and 10 a model protein, insulin, was adsorbed to the surface of LDHs (INS-LDHs) caused by electrostatic 11 interactions. The insulin loading ratio could reach 20% (w/w) and the INS-LDHs were 12 characterized by energy dispersive spectrometer (EDS), Fourier transform infrared spectroscopy 13 (FT-IR), thermogravimetric analysis (TG) and zeta potential measurements. Co-electrodeposition 14 of chitosan and INS-LDHs generated an inorganic and organic composite hydrogel with 15 multilayered structure, as revealed by scanning electron microscopy (SEM). The hybrid hydrogel 16 dramatically reduced the burst release of insulin from INS-LDHs. Significantly, the release of 17 insulin was sensitive to the presence of anions, pHs and external potentials. Our results suggest 18 that co-electrodeposition of stimuli-responsive polymer and nanoplatelets is an alternative and 19 facile method to construct hierarchically structured hybrid hydrogel and the great potential of the 20 multilayered structure in drug delivery. 21 22

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As an efficient manufacturing method for gears, shaping technology developed for non-circular helical gears will greatly break through the dilemma of their applications; especially for those gears with part of pitch curves being concave, being not able to be hobbed. Two fundamental linkage-models for external non-circular helical gears were built based on the meshing theory of non-circular gears in this article. According to four linkage methods in plane and two kinds of additional rotation in vertical direction, eight shaping strategies and their practical linkage-models (1)-(8) were developed. Taking a three-order elliptic helical gear as an example, the kinematic characteristics of the eight practical linkagemodels were analyzed, which reveals that equal arc-length of gear billet (models (3) and (4)) have the highest accuracy under a given efficiency. The dynamic characteristics of models (3) and (4) were analyzed, which shows that model (4) (equal arc-length of gear billet and additional rotation on shaper cutter) is better in performance, and is an optimal one. The optimal linkage-model was demonstrated to be valid by a virtual shaping, and be able to shape those non-circular helical gears with part of pitch curves being concave. Moreover, the accuracy among every gear tooth is uniform. The theory developed and the results of the virtual shaping were illustrated with a shaping experiment. The train of thought and the results will be useful for any external non-circular helical gears with free pitch curves.

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