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This paper describes the function and working principle of the bubble generator of cyclonic static micro-bubble flotation column, the structure of the bubble generator is introduced for the nozzle, induction chamber, pipe, microvoid baffle, diffusion tube, and air suction pipe.Reuse of tailing is a high technology content, environmentally friendly and resources recycle emerging industry. Comprehensive utilization and governance of tailing can bring obvious social benefit, economic benefit and environmental benefits, resource conservation and development is a long-term strategic policy which benefits national economy sustainable development.

This thesis introduces the working principle and structure of FWX series cyclone-static micro-bubble flotation column. It makes industrial test results analysis of the FWX series cyclone-static micro-bubble flotation column adopted by a gold mine, and come at valuable conclusions on the process design and equipment optimization through the analysis of experimental data.

Based on the engineering background of Tangkou in Shandong province, this thesis carries out mining-induced stress distribution law comparative study and analysis of 2313 working face which is lying below-1100 miles, using methods of theoretical analysis, numerical simulation and field measurement, and obtains the limited synergistic effect of mining-induced stress variation and working face advancing steps under the condition of kilometer-deep shaft. That is, with the increase of working face advancing steps, there will be a corresponding increase in the advanced abutment pressure peak, sphere of influence, and the distance from the peak position to the coal wall, within its limit value. The conclusion of this study have some guidance for the safe production and support design of working face in kilometer-deep shaft.

There are large amount of roof water spray in 10# coal seam working face in Tuan Bai coal mine, and the immediate roof with bedding and fractures was fractured. There are also many fallen columns, roof integrity was affected. Varying degrees of damage appeared by adopting traditional I-beam type passive support, when encountered fault, collapse columns and other complex tectonic areas, it prone to collapse accidents. This paper analyses the adaptability of anchor net support, based on the characteristics of coal roadway with water trickling and burst cracked roof, combined field research, coal and rock sampling and underground measures and test methods; by the application of waterproof anchoring agent, making the bolt, the anchorage force meet the design requirements, and ultimately determine the design parameters. Field trails in the headentry, and by analyzing the rock pressure monitoring data, field tests showed that the effect of supporting is good.

Considering the unreasonable noise of laser scanning point data during measuring, which causes the reconstructed curve and surface rough, some problems are analyzed to deal with noise. The mathematical noise model on scanning point cloud is proposed, which consists of deterministic and random noise error, and the random error mainly consists of geometric error and measurement one. The data process is proposed to reduce noise and to simplify data. The noise process consists of obvious noise removed, random filter algorithm and data fairing with an optimized correction value. Due to redundant data about mass point cloud, method of combining deviation parameters with allowed angle is proposed to simplify point cloud. The experiments show that the proposed method has many obvious advantages than a single algorithm of data processing, such as all sorts of noise data can be removed respectively, mass data can be streamlined. And the proposed algorithm has the advantages of high reservation of curve and surface reconstruction of point cloud.

Research situation at home and abroad is described in detail about simplification methods of point cloud data. After analyzing the advantages and disadvantages of existing algorithms, an improved algorithm, a method combining with deviation parameters and allowed angles to simply mass cloud data, is proposed from several aspects of complexity, required time and memory space. The experiments show that the simplified point cloud have a great relationship with the selected tolerance value. And the point cloud after simplification has advantages of high reservation of curve and surface reconstruction perfectly, which is reserved enough data. The proposed simplification algorithm is an effective and practical method.

The effectiveness and actualities of mechanical system virtual prototyping software were summarized. The process from prototype to utility, commercialization and industrialization were analyzed in software engineering. The basic concept of practical improvement for a mechanical system virtual prototyping software was presented. The key points of the mathematical model, topology structure, constraint type, kinematic and dynamic simulation and data exchange were discussed by the theory of multibody system dynamics and the technique of object-oriented.

In the past ten years, various time domain and frequency domain methods for identifying dynamic models of mechanical structures from modal experimental data have appeared. Much attention has been given recently to so-called subspace methods for identifying state space models. In order to better identify state space models of structures, a subspace subid method for identifying parameters is used and performed, and the modal parameters of system is found in the next step. The subid method have so many advantages that, the system identification is convenient to work with the structure modal of multiple-input, multiple-output systems, and the subid algorithm performs equally well and gives well results for the case of white noise excitations as well as coloured noise excitations. Simulations are included to illustrate the ideas discussed on the Mini-Mast flexible structure.

This paper studied the seed germination rate, chlorophyll content, net photosynthetic rate, SOD activity, and Cu and Pb absorption of Agrostis stolonifera and Festuca arundinacea under Cu and Pb pollution. The results showed that Cu and Pb pollution had a significant effect on the seed germination rate of F. arundinacea. The chlorophyll content of F. arundinacea decreased dramatically under Pb and Cu-Pb pollution, while decreased slightly under Cu pollution. No significant effect of Cu and Pb was observed on the chlorophyll content of A. stolonifera. The SOD activity of A. stolonifera increased under 350 mg Cu x kg(-1) and all test concentrations of Pb, while that of F. arundinacea only increased under 700 mg Pb x kg(-1) and 350 mg Cu x kg(-1) + 1100 mg Pb x kg(-1). The net photosynthetic rate of F. arundinacea decreased more under Pb pollution than under Cu pollution, but that of A. stolonifera all decreased under Cu or Pb pollution. It was suggested that A. stolonifera was more tolerant in physiological characteristics to Cu and Pb pollution than F. arundinacea, while F. arundinacea was more tolerant to Cu than to Pb. The Cu absorption amount of F. arundinacea was relatively large, but did not increase with increasing Cu pollution. A. stolonifera had a high absorption ability of Pb, and the absorbed Pb amount was increased with increasing Pb pollution. A. stolonifera and F. arundinace could be the potential phytoremediation plants for Pb and Cu-polluted soil, respectively.