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In this study, the PVDF-BTO composite film was prepared by the casting method. Through FTIR, SEM and other phase structure and microstructure analysis of the composite film, it was found that the introduction of BTO can promote the growth of β-PVDF. The relative content of β-PVDF in PVDF-BTO composite film reached 62.7%, indicating that BTO acts as a nucleating agent in PVDF. PVDF-BTO composite piezoelectric film is obtained after high temperature stretching and field polarization. After testing the electrical properties of the composite piezoelectric film, it is found that the piezoelectric performance of the PVDF-BTO composite film is higher than that of the pure PVDF film. It shows that the blending of BTO and PVDF to prepare the film promotes the deflection of the electrical properties of the film to the inherent electrical properties of BTO. The influence of different polarization intensities on the piezoelectric properties of composite materials was studied. The results show that the optimal polarization intensity of the PVDF-BTO composite piezoelectric film is 30 KV/mm, and the highest piezoelectric constant d33 is 13 pC/N.

We introduce a method to study anisotropic flow parameter vn as a collective probe to Quark Gluon Plasma in relativistic heavy ion collisions. The emphasis is put on the use of the Fourier expansion of initial spatial azimuthal distributions of participant nucleons in the overlapped region. The coefficients n of Fourier expansion are called the spatial anisotropy parameter for the n-th harmonic. We propose that collective dynamics can be studied by vn/n. In this paper, we will discuss in particular the second (n = 2) and the fourth (n = 4) harmonics.

Chaotic characteristics in the iteration of logistic map(one-dimensional discrete dynamic system) are simulated and analyzed. The circuit implementation of a kind of chaotic amplifier model is based on the chaotic characteristics that chaos is sensitively dependent on its initial conditions, and the circuit simulation result is given using simulation program with integrated circuit emphasis for personal computer (PSPICE), and is compared with linear amplifier. Advantages and disadvantages of such a model are indicated.

Tensile tests on two similar 75-μm-thick aluminium sheet materials were carried out inside a scanning electron microscope equipped with an electron backscatter detector. The materials were subjected to simulated brazing prior to the test because this type of material is used for fins in automotive heat exchangers. Grain sizes were large relative to sheet thickness and ND-rotated cube and P texture components dominated the recrystallization textures; their volume fractions differed strongly in the two different materials, though. Strains over the microscope image fields were determined from positions of constituent particles or from grain sizes; the two methods gave consistent results. Grains with high Schmid factors accumulated significantly more deformation than grains with low Schmid factors. Cracks nucleated in high-Schmid factor grains, or in groups of such grains, at the specimen edges. When only low-Schmid factor grains were present at the specimen edges, the crack nucleated inside the specimen. The subsequent crack growth was intragranular and occurred at approximately 90° relative to the load direction.

Using the shower parton distributions determined by the recombination model, we predict the fragmentation functions for heavy baryons. Then we obtain the completed fragmentation functions of heavy quarks (c and b) splitting into their hadrons (mesons and baryons containing one heavy valence quark). The calculated process shows that the fragmentation functions for mesons and baryons are not independent if the hadronization of the shower partons is taken into account.