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A kind of theoretical analysis method in wall climbing robot design is presented in this paper. Using this method, a flexible wall climbing robot is developed that can be well adopted in small irregular places. Firstly, an optimization mechanism is given based on the effective utilization of aerodynamic attraction produced by a centrifugal blower. Kinematics model of the robot is represented, then linear velocity function and angular velocity function of the robot are deduced. Dynamic model based on Lagrange equation is established, which can be a theoretical foundation for control system design. Finally, simulation results show that the dynamic model and the method are reliable since the curves of driving torque match the change of negative pressure.

The anaerobic fermentation characteristics of green and dried corn straw pretreated by steam explosion method were investigated. The steam pressure and retention time were 1.0Mpa and 90s, TS of fermentation liquid were 2% and 4%. It was shown that the fermentation cycle of green straw is shorter than that of the dried one by 4-7 days, the gas productivity of green straw is 220 mL/gVS, which is higher than that of dried one (153 mL/gVS) while TS is 2%, but there is no significant difference between the green and dried corn straw while TS is 4%, the average methane content in biogas produced from green straw is slightly less than that of the dried one.

Perovskite KTa0.65Nb0.35O3 (KTN) thin films were grown by pulsed laser deposition (PLD) on single crystal SrTiO3 (100) substrates. X-ray diffraction (XRD) analyses illustrate epitaxially grown of KTN thin films along the (100) orientation. The surface morphology of films observed by atomic force microscope (AFM) showed that, the surface of films was smooth and uniform built from regular, ordered and dense grains with the root mean square (RMS) roughness of 5.602 nm. Linear and third-order nonlinear optical properties of the films were investigated by using transmission spectra as well as the Z-scan technique with femtosecond laser pulses, respectively. The open-aperture and closed-aperture Z-scan curves of KTN thin films were obtained in the first measurement. The calculated nonlinear refractive index was , the nonlinear absorption coefficient is = , and the real part and imaginary part of the third order nonlinear susceptibility are and respectively.