Effects of amount of Ca on crystal structure, microstructure, ferroelectric properties, and dielectric properties of the CaxSr2-xBi4Ti5O18 (CSBTi-x) ferroelectric ceramics were investigated. The results show that single-phase layered perovskite ferroelectrics were obtained and no appreciable secondary phase was found.Ca-doping results in a notable enlargement of remnant polarization 2Pr. The 2Pr of CSBT-0.15 reaches a large value, the remnant polarization 2Pr and coercive field 2Ec were 18.1µC/cm2 and 120.2kV/cm, respectively. Dielectric constant and dielectric loss of CSBT-0.15 was also measured, showing dielectric constant εr=199~194 and dielectric loss tanδ=0.02~0.014 over the range of 100 kHz~1MHz, respectively.

In this paper, we show how a MAT (Mesh-of-Appendixed-Trees) embedded into the crossed cube which is a variant of hypercube. When we seek to implement this MAT-based mapping scheme on a crossed cube machine, we solve the two following questions: an N×N MAT can be embedded into a crossed cube of 4N2 nodes and the smallest size crossed cube to embody an N×N MAT has 4N2 nodes.

Ca1-xSrxBi4Ti4O15 thin films were fabricated by sol-gel method on Pt(100)/Ti/SiO2/Si substrates. Influence of Sr content on the microstructure and ferroelectric properties of Ca1-xSrxBi4Ti4O15 thin films were systematically studied. The results indicate that Ca0.4Sr0.6Bi4Ti4O15 thin film has better ferroelectric properties with remanent polarization (2Pr) of 29.1+C/cm2, coercive field (2Ec) of 220 kV/cm. Furthermore, the film has good fatigue resistance. The better ferroelectric properties of Ca0.4Sr0.6Bi4Ti4O15 thin film originate from the relatively high concentration of a-axis oriented grains.

s. The theory teaching of the physical properties of inorganic materials in classroom has the characteristics of strong theoretical and boring content, so students prone to boredom. This course covers the mechanical deformation, brittle fracture, intensity, thermal and electrical performance of inorganic materials. Furthermore, the environmental teaching is just verification tests, lacking of the phenomenon of creativity. As a result, it’s of great significance to reform the curriculum.

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