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Regular line and circle arry micro-apparatus on 65Mn plate formed by femtosecond direct writting with wavelength of 800 nm, repetition rate of 1 kHz and the pulse length of 130fs in air. Investigate the effect of pulse energy and scan speed. Found, that the increased scan speed was similar to the decreased pulse energy. Due to the circle pattern was different to the line process, the contrary phenomenon appeared, which with increased ablation energy, the width of groove was less and the depth was increased.

Regular micro-apparatus which covered with periodic nano-hole, nano-ridge and ripple structures on silicon bulk were formed by laser micro-machining with tightly focused beam of the femtosecond laser with wavelength of 800 nm, repetition rate of 1 kHz and the pulse length of 130 fs in air. The periodic nano-hole structures which focus with a 20× focusing objective lens (NA = 0.4) is reported. Investigating the relationship between the width of structures and the speed of processing.

An aqueduct of larger-span prestressed concrete arch structure for river diversion project is located in coastal areas, and raises difficult questions on deformation and stability control of the construction process due to greater wind load and poor soil. Due to the limited width of bracket erection, this paper put forward five possible construction schemes, and does the comparative analysis using three-dimensional finite element program, and gets the economic and reasonable one. Finally conduct a pressure test after the bracket erection, and verify the analysis results using measured stress and deformation data.

With femtosecond laser pulse (130 fs, 800 nm, 1 kHz pulse repetition frequency) irradiation on Au/Cr film stack, several nanostructures were obtained. The influence of laser parameters such as fluence(0.5J/cm2,2J/cm2) and the number of pulse were investigate. With single pulse irradiation, the nanoline and periodic ripple structures were obtained for the pulse fluence of 0.5J/cm2 and 2J/cm2, respectively. The formation mechanism of those nanostructures were discussed.

The plasma was generated by focusing a pulsed Nd:YAG laser at 1064nm and 10ns on the surface of ITO. We investigated the relationship between the signal intensity of LIBS and the pulse energy of laser, and found the signal of the analyze lines of In and Sn increased with the laser energy enhanced proportional. A series of measurements were made to found the optimum time delay between the laser pulse and the beginning of the LIBS spectra acquisition. Through calibration-free method we obtain the temperature of plasma,at the same time we measured the content of In and Sn by the program which writed with matlab.

The periodic microstructures on 65Mn plate were induced by the irradiation of the femtosecond laser with the laser wavelength of 800 nm and the pulse length of 130 fs. The parallel periodic ripples structures were observed at the laser fluence of 1 J/cm2 with different pulses number( N=5,50,400,800) which lied parallel to the laser electric polarization field vector. For 400 pulses, the nano-holes arrays were generated to interrupt the consistent ripples structures.For 800 pulses, initial nano-holes evolution to the grooves, which the direction were uncertainly. Further experiments have been made to induce large area consitent ripple structures by scanning, at the laser fluence of 1 J/cm2 with speed v=500μm/s. 2D arrays were induced by accurate processing control