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This paper compares the microstructure and electrochemical properties of the diamond-like carbon films obtained by two different deposition methods - microwave electron cyclotron resonance plasma enhanced chemical vapor deposition (MWECR-PECVD) techniques and electro-deposition – chosen for their low cost and capacity to produce films. The microstructure of the DLC films are investigated by Raman spectroscopy, FTIR spectroscopy, and electrochemical behavior is investigated by potentiodynamic and electrochemical impedance spectroscopy (EIS). Raman spectroscopy indicates that all the films deposited by different techniques show amorphous structure and typical characteristic of DLC film. FTIR spectrum results indicate that these DLC films are a-C:H films. As a result of EIS, the DLC films made by different methods showed obviously different electrochemical characters. The obtained results show that the DLC films deposited using the PECVD methods provided the better results, presenting a high corrosion resistance , high adherence to substrate, and a denser and more uniform surface.

Based on Shandong Renping Bayer red mud as the raw material, analyzing its basic characteristics, the result is that the content of total iron in red mud is 29.55%. Gas-based high-temperature direct reduction experiments are made by using a gas mixture of CO and H2O as a reducing agent. And then the reduction effect was investigated by magnetic separation experiments, to realize that separation of iron minerals from red mud. The results show that the consequent of the magnetic separation is improved obviously with the temperature rising. Under these conditions, namely, the roasting temperature being 1050°C, the roasting time lasting 90 minutes, the reduction gas rate being 0.7 m3/min, the magnetic field being 2.2A, and three magnetic separations, the iron recovery ratio in red mud is over 97%.

A low-cost raw material, bittern obtained from the production process of sea salt, was used to prepare magnesium oxysulfate hydrate (MgSO4·5Mg (OH)2·2H2O, abbreviated as 152MOS) whiskers via hydrothermal synthesis with ammonia and magnesium sulfate as the other starting raw materials. The bittern was firstly filtered and then used directly without de-coloring. X-ray powder diffraction (XRD), transmission electron microscope (TEM), selected area electron diffraction (SAED), energy dispersive X-ray spectroscopy (EDX) and scanning electron microscope (SEM) were employed to investigate the composition and morphology of the products. It was found that the 152MOS whiskers synthesized from bittern at 190°C for 3 hours exhibited fanlike morphology. The formation of the fanlike whiskers was inhibited and most of the whiskers presented as single fibers when ethanol was used as crystal control agent in the hydrothermal process. From the two-dimensional steps observed at tips of the whiskers, a possible growth mechanism was speculated that it was the extension of dislocations that made the growth of the whiskers.