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Multiferroic 0.7BiFeO 3 –0.3PbTiO 3 (BFO–PT) thin films have been prepared by a sol–gel method on Pt/Ti/SiO 2 /Si substrates. A strong dielectric dispersion was observed above 10 kHz and a relatively low dielectric loss was found at low frequencies. The BFO–PT thin films exhibit both ferroelectricity and (week) ferromagnetism with P r = 13.7 μC/cm 2 and M S = 3200 A/m at room temperature, confirming the multiferroic properties. The local polar domain structure and ferroelectric switching of the thin films were investigated by piezoresponse force microscopy.

Dispersion corrected density functional theory (DFT-D2) were employed to investigate the distribution of Al in the framework of H-[Al]MOR and the strengths of Bronsted acid sites by NH3 adsorption. Thermodynamically, the most favorable site for distribution of Al is T2O5, followed by T4O2, T1O7 and T3O1, which are a little higher in energy when Al is incorporated. It was found that the energy differences for Al in different T sites are 0.03–0.07 eV, indicating that the Al atoms might distribute in all kinds of four non-equivalent crystallographic tetrahedral sites of MOR. Moreover, it is also suggested that the location of protons plays an important role in the stability of the Al substitution site. In addition, we also computed the adsorption energies for NH3 adsorbed at each crystallographic position of H-[Al]MOR by DFT and DFT-D2, respectively. By comparison, the DFT method always underestimates the substitution energy by 0.41 eV for the adsorption of NH3, indicating that the dispersion correction is necessary to calculate the adsorption of NH3 in H-MOR. The results show that the Bronsted acid site at T2O5 is stronger than the other acid sites, and the adsorption of NH3 on the Lewis acid sites is clearly weaker than on the Bronsted acid sites.

In this study, the investigation of the three-dimensional nonlinear dynamics of a fluid-conveying pipe undergoing overall motions is carried out. Considering the effect of the internal and external fluids, and using a non-Cartesian variable along with two Cartesian variables to describe the elastic deformation, the nonlinear differential equations are derived based on Kane’s equation in combination with the Ritz method. An alternative approach to the existing methods utilizing Newtonian balance equations or Hamilton’s principle is thus provided. The equations of motion are linearized in the neighborhood of the equilibrium position to implement the multimode linear stability analysis. In addition, the time histories for the displacements are obtained with the help of the Incremental Harmonic Balance (IHB) method. The validity of the new modelling is substantiated by comparing the model and results with those proposed by Paidoussis (1998).

Xe ions at energies from 50 to 400 keV as well as from 600, 800 and 1000 keV were implanted into Si and Si1N1.375H0.603, respectively. The mean projected ranges and range stragglings are measured by Rutherford backscattering of MeV He ions. The values obtained are compared with different calculation procedures. The results show that the maximum differences between experimental and calculated values are 11%, 14% and 7% by transport of ions in matter (TRIM), projected range algorithm (PRAL) and Wang and Shi (WS) calculation procedure based on Biersack's model, respectively. The experimental range stragglings are higher than the calculated ones for the case of 50–400 keV Xe ions implanted into amorphous Si. As for the case of 600, 800 and 1000 keV Xe implanted into Si1N1.375H0.603, the maximum differences between experimental and calculated values of the mean projected range are 25%, 26% and 15% by TRIM, PRAL and WS, respectively. Also it is observed that there are significant deviations of the experimental values from the calculated values for the range straggling.

Range profiles of Hg+ implanted at energies from 50 to 400 keV in quartz crystal are measured by MeV 4He+ Rutherford backscattering. The measured projected ranges and range stragglings are compared with the Biersack theory. The result shows that the agreement between the experimental and calculated values is quite good for the projected ranges; after including second order energy loss terms, a better agreement for the range straggling is obtained.