We have theoretically studied fundamental shot noise properties in single- and dual-gated silicene nanostructures. It is demonstrated here that due to the intrinsic spin–orbit gap, the Fano factor (F) in the biased structures does not coincide with the characteristic value F = 1/3, a value frequently reported for a graphene system. Under gate-field modulations, the F in the gated structure can be efficiently engineered and the specific evolution of the F versus the field strength is symmetric with the center of spectra oppositely shifting away from the zero field condition for the valley or spin-coupled spinor states. This field-dependent hysteretic loop thus offers some flexible methods to distinguish one spinor state from its valley or spin-coupled state via their numerical difference in the F once the incident beam is spin or valley-polarized.

The centrifugal pump is the common mechanical equipment, which is extensively applied in the water conservancy, ships and other projects, and the blade structure is a very important part in the centrifugal pump. In this paper, the stress distribution and concentration of single blade in the impeller are analyzed under the different pressure field of the blade structure surface, and the fatigue failure of blade is also studied. The research results show that the we can get the stress and strain of the blade accurately and intuitively through the analysis for the blade structure, the stress concentration of the centrifugal pump blade is mainly in the root and junction of the wheel cover, and the import value of stress concentration is larger than the outlet; the stress concentration may be caused easily as the stress increases rapidly in the blade, which has a great impact on the fatigue strength, the fatigue limit of the blade with the stress concentration is decreased more obviously than the fatigue limit of the smooth blade.

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Wire Suspension is widely used in sensors, especially support the DVD actuator in each of side. The mechanics model of it can be regarded as cantilever beam. The dynamic model of the gear is established by FEM（Finite element method）and modal analyses of the wire suspension are investigated by ANSYS software.

The lens actuator is the important mechanical-electrical component in the optical disk reading/recording system. According to the error signals from the optical pickup reading/writing process, namely the focusing and tracking error signals, the focusing coils as well as the tracking coils are applied the corresponding corrective current (or voltage), thus, the force generated by the current-on coils in the magnetic field will real-time actuate the objective lens to make the focusing spot precisely fall on the disc information track, realizing the data reading/writing. As wire suspension type, the suspension model determines the wire design process. According to the material mechanics, the force distribution on the wires is analyzed and the four wire suspension model is set up, thus, the wire parameters are designated and the natural frequency as well as the static sensitivity of the moving part can be determined. After serial material experiments using Instron 5848 Microtester, better treatment for the wire fabrication is adopted with 1.5 hour aging and sliver cover-layer.Moreover, the actuator with the suspension wire is tested by the laser vibrometer and results show the good performance of the actuator, which proves the feasibility of the suspension model. Although the suspension model is set up on the four wire suspension actuator used in DVD-ROM, it can also be used in the six wire suspension actuator in the HD DVD and Blu-Ray.