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Aiming at the poor machining quality of workpiece caused by lack of systematic theory and blind selection of processing parameters of ultrasonic cutting honeycomb composites, study on ultrasonic cutting force and selection of processing parameters of ultrasonic cutting honeycomb composites on straight blade cutter were carried out. The theory model between ultrasonic cutting force and procees parameters was established base on analysis of tool's kinematics characteristic. Based on model, the change of cutting force caused by ultrasonic vibration energy was investigated. The influence rules of processing parameters on ultrasonic cutting force were investigated through simulation analysis on the Matlab software. The results indicate that ultrasonic cutting can effectively reduce cutting force compared with traditional machining, nose angle and blade surface angle has the most significant influence on cutting force, the next is top angle, however swinging angle has minimal influence on cutting force, and lays the good theory foundation for reasonable selection and further optimization of proceesing parameters. [ABSTRACT FROM AUTHOR]

Abstract: Nano-TiO2 colloids have been successively prepared by focused, pulsed laser ablation (PLA) at the interface of solid titanium dioxide and flowing liquid. Three factors influenced the luminescence of the nano-TiO2 colloids. The first factor was the flowing rates of the flowing liquid. The second factor was the pulsed laser output power. The third factor was the age of the colloids. The nano-TiO2 colloids products were characterized by transmission electron microscopy (TEM), ultraviolet visible spectroscopy (UV–vis) and fluorescence spectroscopy. The results revealed that anhydrous ethanol was the best flowing liquid, and cyclohexane or water was found to be not suitable for this system; under the conditions of the lowest flowing rates of the flowing liquids in the range of 0.017–0.15mL/s, the highest pulsed laser output power in the range of 100–250mJ/pulse and with the proper aging time of the colloids, nano-TiO2 ethanol colloids with strong fluorescence emission intensity at about 414nm can be obtained. [Copyright &y& Elsevier]

Abstract: A sort of surface fine-decorated in situ Tb2O3 nanoparticles in ethanol sols were successively prepared by focused pulsed laser ablation at the interface of Tb2O3 target submerged in flowing liquid containing modifiers, and it is found that the nanoTb2O3 sol decorated by acac and 2,2′-bipy can emit very intense characteristic fluorescence at 549nm of Tb3+ ions, which is different from nondecorated nanoTb2O3 ethanol sols with only low fluorescence at 415nm. [Copyright &y& Elsevier]