AC servo system has been widely used in many fields with its high performance and the fast development of intelligent control strategy. Targeted at the single-axis motion control applications in industrial automation, a kind of single-axis motion control system, based on FM354 controlled by S7-300 PLC, is designed. The system consists of three to the position, speed and current closed-loop control to achieve precise position control. The position loop is implemented by FM354. The speed loop and current loop are encapsulated in the servo driver. Through monitoring and comparing the dynamic performance with traditional systems, it can find out the bench runs smoothly and positioning accurately, perfectly meeting the technological and application requirements. It also can be applied to a variety of occasions and used for multi-axis extension.

Aiming at the shortcoming of Lebus grooving with conventional lathe,a new NC machining method was put forward based on synchronously following technology,and the detailed algorithm was explained.The results of simulation and testing show that the method is effective in Lebus grooving by NC.

For the shortcoming of the manual finding round billet centre in the processing technic of hot rolling seamless steel tube,it puts forward an automatic finding centre method based on laser real-time synchronous scanning the round billet outline,and the centre is simultaneously calculated by on-line least square method.The structure and working principle of the PLC self-centering control system is related and analyzed.The test shows that the system is very good to meet the billet self-centering requirements.

A rapid liquid chromatograph-electro-spray ionization(ESI) tandem mass spectrometric method was developed for the quantification of lafutidine in human plasma.Separation was performed using a Kromasil CN column(4.6 mm×150 mm,5 μm)maintained at 30℃ and the mobile phase consisting of a mixture of methyl alcohol and water(containing 20 mmol·L-1 ammonium acetate and 0.05% formic acid)(97∶3) was delivered at a flow rate of 1.0 mL·min-1;The analytes were analyzed by ESI in a multiple reaction monitoring(MRM) mode.The precursor to product ion transition of m/z 432.20→351.15 and m/z 275.10→230.05 were used to measure lafutidine and IS,respectively.The linearity ranged from 1.98 to 396 ng·mL-1(r=0.9991) and the limit of detection of lafutidine in human plasma was 1.98 ng·mL-1.The intra-and inter-assay precisions,accuracy and absolute recovery met the requirements of bioanalytical method,significant matrix effect was absent.The method is selective and suitable for the quantification of lafutidine in human plasma clinically.