The effect of rod arrangement in a rod matrix on high gradient magnetic separation (HGMS) performance has been comparatively investigated through a cyclic pilot-scale centrifugal HGMS separator, with contiguously and orthogonally arranged rod matrixes respectively. The results of investigation indicate that the arrangement of rod elements in the matrix has a distinct effect on the HGMS performance, for relatively low magnetic inductions; beyond the threshold magnetic induction, the magnetic induction dominates that of the arrangement and the importance of the arrangement is significantly weakened even vanished. It was thus concluded that the combinatorial optimization for magnetic elements in the matrix improves the collision efficiency of particles with matrix, and gives a superior performance in a HGMS separator, at a lower energizing consumption.

Based on process mineralogical study of an oolitic hematite ore in SW China, the texture and structure of the ores, the occurrence of iron minerals and the dissemination of them are determined in detail, which provides scientific reference for forthcoming mineral processing technology. The mineralogical results show that the sizes of the grains are generally under 0.01mm, so the minerals cannot be liberated completely by traditional grinding technology. Moreover, the objective minerals are the assemblages of hematite and chlorite, whose amount is highly variable, so the magnetism also varies widely. Therefore, during the coming magnetic separation tests, the increment of the magnetic intensity should be strictly manipulated to determine the best condition for the ores.

The paper takes the numerical control milling machine xk8140 as the research object. The machine tools spindle system digital model is established in UG. The spindle systems natural frequency is obtained throng dynamics analysis of milling machine spindle under specific working conditions, as well as the relational of vibration and error in harmony response situation. In view of the result the rational appraisal to the spindle system structure rationality is made. Accordingly, the irrational causes removed, that noise increasing, processing quality reducing obviously and so on attribute to the irrational structure of the spindle system machine tools when the spindle rotational speed achieve 4000rpm or higher.

The activation effects of single activator and some combined activators on Yunnan copper oxide ore were studied with Drawing a conclusion that the best activation - xanthate flotation result could be obtained by using sodium sulfide and ethylenediamine phosphate as the combined activator. on this basis, the open and closed circuit flotation tests were done , and in the closed circuit flotation test ,the flotation concentrate with yield of 5.90%, copper grade of 16.01% and recovery of 74.38% was obtained

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