Teaching of Chongqing Institute of Engineering"

With the advent of the"Internet+"era and the development of educational informatization,smart teaching will become an important form of education and teaching.This paper starts with the concept and characteristics of smart teaching and takes the course"Innovation and Entrepreneurship Foundation"as an example.Based on the platform of"Smart Teaching of Chongqing Institute of Engineering",smart teaching practice and research is carried out in four stages:pre-class teaching,in-class teaching,after-class teaching,and teaching evaluation.The practice has proved that this new teaching mode realizes the complementary advantages of online and offline teaching,stimulates students'interest and initiative in learning,improves the teaching quality of the course,and has good application value.

Lead zirconate(PbZrO_(3))embedded in natural rubber as electroactive elastomer composites

Perovskite lead zirconate(PbZrOz)was synthesized in an orthorhombic form at a temperature below the Curie temperature,Tc.The orthorhombic form is a noncentrosymmetric structure which is capable of spontaneous polarization.Fourier transform infrared(FTIR)spectra and X-ray diffraction(XRD)patterns confirm the siuccessful synthesis of the lead zirconate;and scanning electron microscopy(SEM)micrographs indicate that PbZrO_(3) particles are moderately dispersed in the natural rubber(NR)matrix.Without an electrical field,the particles merely act as a ferroelectric fller,which can absorb and store additional stress.Under an electrical field,particle induced dipole motents are generated,leading to interparticle interaction and a sub-stantial increase in the storage modulus.At a small amount of lead ziroonate part iculates present in the natural rubber matrix,at a volume fraction of 0.007306,the electrical conductivity increases dramatically by nearly two orders of magnitude at the electrical frequency of 500 kHz.