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Unsupported MoS2hydrodesulfurization(HDS) catalysts is sulfide in its original state, so there is no need to add toxic sulfur compounds to presulfurize the hydrogenation catalyst, which has ultra-high capacity to HDS and causing attentions. This paper focuses on summarizing the preparation, characterization and desulfurization mechanism of unsupported nano MoS2catalyst and provides its future research directions.

Abstract. The antibacterial activity of the five dimeric quaternary ammonium amphiphiles against Escherichia coli were evaluated by determining the minimum inhibitory concentration (MIC) and compared with one monomeric quaternary ammonium amphiphile. The antibacterial activity of dimeric amphiphiles is superior to the corresponding monomeric amphiphile. The action mechanism was investigated by measuring the activity of β-galactosidase from E. coli and scanning electron microscopy (SEM) imaging of E. coli cells. The result of β-galactosidase activity shows that 12-8-12 disrupts the membrane of E.coli leading to the releasing of intracellular contents and death of bacterial cells. This conclusion was supported by scanning electron microscopy, which imaged the holes on the cell membrane and irregular shape of cells caused by treatment of 12-8-12.

This paper presented a real-time measuring method of temperature fields and thermal deformations in vertical machining center. And a FEA model including the thermal contact resistance at interface for evaluating the temperature distribution and tools deformation in vertical machining center (VMC) was established. Compared with the experiment results, it is shown that the new model is much more accurate than the traditional model without considering thermal contact resistance at interface.