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Cr Si–M (M Ni, Mo, Ni Mo) resistive films were prepared by magnetron sputtering technique at the same process conditions. Experimental results shows that the metal M can reduce the temperature coefficient of resistance (TCR) of Si-rich Cr Si resistive films, and that the resistive films follow the sequence of Cr Si Mo (6.34 at%) < Cr Si Ni (9.97 at%) < Cr Si Ni (6.08 at%) Mo (2.47 at%) according to TCR tending to zero. XRD analysis reveals that CrSi 2 is the main conductive phase in the prepared Cr Si–M resistive films. In order to explore the reasons that M can reduce the TCR of Si-rich Cr Si resistive films, first principles was used to study the influence of M on the performance of CrSi 2 from state density and band structure. The first-principles study on M-doped CrSi 2 shows that M may exist in CrSi 2 semiconductor in the form of deep level impurity, and an energy band model on both Ni and Mo-doped CrSi 2 is constructed to reflect the results of first-principles simulation. Based on the established model, a mechanism is proposed that deep level impurities as electron traps capturing electrons and the formation of tight-binding excitons can suppress the non-equilibrium hot carriers against being contributed to the conductivity of CrSi 2 semiconductor. As a result, the TCR of Si-rich Cr Si resistive films is reduced due to the doping of M as deep level impurity. [ABSTRACT FROM AUTHOR]

This paper investigates the free transverse vibration of a wrinkled annular thin film. The non-dimensional Hamilton motion equation of the wrinkled annular thin film is established, which is solved by using the finite difference method to acquire the vibration frequency and mode. The predicted vibration characteristics are verified by the experimental measurements based on the digital image correlation (DIC) technique. The results show that wrinkles have great effects on the vibration of the annular thin film. Especially for the heavily wrinkled cases, the local–global interactive mode dominates the vibration of the annular thin film. The frequency increases as the wrinkling level increases which is mainly due to the increased nonlinear geometric stiffness. The results provide favorable supports for understanding the role of nonlinear wrinkling on the vibration of thin films. [ABSTRACT FROM AUTHOR]

Abstract: Based on Wuʼs elimination method and homotopy analysis method (HAM), an algorithm is proposed to compute accurate analytic approximation of periodical oscillations with high nonlinearity. A Maple package is developed for periodically oscillating systems of center and limit cycle types, which delivers accurate approximations of frequency, mean of motion and amplitude of oscillation automatically. Since HAM is valid for highly nonlinear problems, the package can be used to find accurate approximate solutions of nonlinear oscillation systems with strong nonlinearity. For systems with physical parameters, it can provide possible constraint conditions on parameters. Several examples are given to illustrate the validity and effectiveness of the algorithm and the Maple package. This package is freely available online, which provides an easy-to-use tool for scientist and engineer to solve accurate approximations of periodic oscillations of dynamic systems with high nonlinearity. [Copyright &y& Elsevier]