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In the present study, sawing forces of Al2O3 ceramic and wear of metal-bonded diamond cut-off wheel were examined by counting the statistical data of diamond wear and analyzing the force signals under different sawing conditions. The experimental results demonstrated that normal grinding force reduced with the increasing of sawing speed, and rose with the increasing of workpiece feed rate and grinding depth. In all of the variables, sawing depth made the greatest effects on normal grinding froce. The percentage of whole crystal or pull-out crystal decreased and fractured crystal increased as the sawing depth increased or the sawing speed decreased. Among machining factors, sawing speed was the greatest effectors on the wear of diamond cut-off wheel.

In electrolytes TiO2-based complex ceramic coatings containing Ca and P on titanium alloy were ultimately formed containing zirconia/hydroxyapatite by Micro-arc oxidation process. As well as the biomechanics measure experiment of speciments had been done, and the datas were analysised and researched. In addition, the toughening mechanism of reinforced coating was studied in detail, and consists of the second phase toughening, phase transformation toughening and microcrack toughening.The results show that the zirconia /hydroxyapatite coating has advanced biomechanics propertys compared to the individual hydroxyapatite one.

A new kind of suspending combination ecological filter bed was constructed, which took floating baskets as basic units and took flyash cenospheres and attapulgite clay ultra light filter material as loading material. It integrated plant absorption, filter material adsorption with biofilm colonization to purify wastewater. Experiment showed that by the use of filter bed, TP, TN and COD can be removed effectively. Three kinds of plants, including green vegetables, spinach and American-four-season-green grass were cultivated in the filter bed and grew better than those planted in soils. Germination rate and speed of growth were faster than the controlled group. The application of filter bed didn't need land occupation and civil engineering construction. Meanwhile, it can restore the polluted water, reduce the operation costs and fulfill the recycling of eutrophia water.

A new method of NC machining simulation based optimization of cutting parameters is proposed. For the case of NC turning process, the method of extracting cutting parameters from NC programs is given. Based on the cutting theories, using linear weighted method, the multi-objective optimization function is constructed, and it is solved by complex method. The modification and storage strategy of parameters is also given. The application shows that the proposed method cannot only ensure the accuracy of NC code, but also provide the optimized cutting parameters under the constraints of appointed machine tools. It will be helpful for the optimization and intelligence of NC machining.

A medicinal titanium alloy hydroxyapatite coating was fabricated by microarc oxidation process, and a kind standard of simulated body fluid was configured, after that the biocompatibility experiment was carried out. The soaked coatings surface morphologies were observed and analysed by scanning electron microscopy,and the coating spectra were simultaneityly researched by X-ray diffraction. The instance of degradation and precipitate were investigated,and the transformation of Ca/P value were measured.