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In this paper, a ball mill gear reducer was regarded as the research object. Based on the HMM pattern recognition theory, DHMM methods that were used in fault diagnosis had been researched. The vibration signal was required a series transformations which are feature extraction, normalization, scalarization and quantization to get the sequence collections. Then the quantified sequence collections were trained to get the DHMM parameter, or the Viterbi Algorithm which was used for the quantified sequence collections to calculate the maximum probability, thereby the DHMM fault models library was established or the type of fault was recognized. Experiments of five kinds of fault model diagnosis were carried out in this article.

This paper studied the photocatalytic reduction kinetics of bromate in aqueous dispersion of TiO2 and investigated the effects of experimental parameters, including initial concentration of BrO3-, pH, TiO2 dosage, anion and cation. The results indicate that the process of photocatalytic reduction of bromate follows a zero-order kinetics. In all the investigated experimental parameters, the initial bromate concentration, pH and anion have great effect on the photocatalytic reduction kinetics. The processes of photocatalytic reduction of bromate show the pseudo first-order kinetics at initial bromate concentration of 0.39 μmolL-1, pH=5.0, or in presence of HCO3-/CO32-, NO3-, SO42-, respectively.

A series of Ir-supported catalysts were prepared by incipient impregnation method. The activity of Ir catalyst for the simultaneous removal of soot and NOx in the presence of rich-oxygen and H2O as well as SO2 has been studied, and the effects of calcination temperature, calcination time, calcination atmosphere, loading, carrier and precursor on its catalytic performance has also been investigated. Ir catalyst exhibits a high activity. With the calcination temperature increasing, Ir catalytic activity increases firstly and then decreases, and the optimal calcination temperature is 900°C. With the calcination time prolonged, Ir catalytic activity also increases firstly and then decreases, and the optimal calcination time is 3h. The optimal calcination atmosphere is 1.5vol.% H2/N2. Support material and precursor have a little effect on the catalytic activity, and the order is Ir/TiO2 > Ir/ZrO2 > Ir/SiO2 > Ir/Al2O3 > Ir/ZSM-5 and IrCl (CO)[P(C6H5)3]2/ZrO2 > H2IrCl6·6H2O/ZrO2 > IrCl4·4H2O/ZrO2.

The effects of various inorganic anions (SO42−, NO3−, HCO3−/CO32−, Cl− and I−) on the photocatalytic reduction of BrO3- were investigated under UV light irradiation. The effects of the inorganic anions depend strongly on the property of radical scavenging and adsorption. At the concentration of 1.56 μmol/L, NO3−, SO42−, HCO3−/CO32−, Cl− and I− exhibit the property of radical scavenging and promote the reduction of bromate. At higher concentration than 1.56 μmol/L, NO3−, SO42−, and HCO3−/CO32− exhibit the property of adsorption and decrease the promotion of the reduction of bromate. Cl− has little effect on the reduction of bromate, it is due to the ability of the radical scavenging is lower than that of Br−. Only I− has a higher promotion of the reduction of bromate at higher concentration than 15. 64 μmol/L, it is due to the strongly reduction potential E0(•I/ I−).

Self-combustion of oil shale has been occurring and widespread in a long term while oil shale was considerably piled in Fushun dumping sites. After collecting samples of high- and low-grade oil shale from Fushun West Open Mine, the self-combusted oil shale from Fushun West Dumping Site, and designing the indoor high-temperature incineration experiments to simulate the self- combustion process, we tested trace elements in them and their ashes of 700°C, 1000°C by means of ICP-MS. Based on the analysis and comparison of the test dada, we studied content characteristics and migration pattern of elements during self-combustion. The results showed that elements were distributed in the similar way in samples and contents of Zr, Sr, Cr, V, Zn, Ni, Rb and Li were very high. A large amounts of trace elements were found to enter the atmosphere through volatilization in the process of Self-combustion, especially those higher volatile elements, such as Sb, Zn, Pb, W, Sn, Ta and Cd, while a few elements preferred to concentrate in solid-phase ashes. Different distribution and migration capacities of elements might be the main reason for the higher concentration of some elements in self-combusted oil shale than their background values in Liaoning soil.