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Adsorption desulfurization is a potential new method for deep desulfurization of fuel oil. The development of adsorbents with high adsorption capacity and selectivity is the core of deep adsorption desulfurization. The adsorption behavior of thiophene in MCM-41 mesoporous materials modified by various metal ions was studied in order to understand the adsorption desulfurization process of molecular sieves. The Fe-, Co-, and Zn-modified MCM-41 materials were prepared using a one-step in situ hydrothermal synthesis method. The modified MCM-41 molecular sieves maintained the mesoporous structure, and the metal ions had specific dispersion on the surface of the molecular sieves. Adsorption of thiophene on the surfaces of molecular sieves had both physical and chemical characteristics. The adsorption desulfurization performance of the modified molecular sieve was superior to that of the pure silica molecular sieve. In the simulated gasoline with sulfur content of 220 μg/g, when the amount of adsorbent used was 100 mg, the adsorptive desulfurization performance tended to be in equilibrium, and the optimum adsorption temperature was 30°C. Fe-MCM-41 and MCM-41 molecular sieves reached adsorption equilibrium after ~60 min, but the desulfurization rate of Co-MCM-41 and Zn-MCM-41 still increased slightly. The kinetic simulation results indicated that the pseudo-second-order kinetics adsorption model described well the adsorption process of thiophene on molecular sieves. The molecular sieve Fe-MCM-41 had the best desulfurization performance with an equilibrium adsorption capacity of 14.02 mg/g and the desulfurization rate was ~90%.

This work aims to explore the sources of raw materials of archaic serpentine jade artifacts by comparing their trace element content. The major and trace elements of serpentine jade samples from different deposits in China are determined by external-beam proton-induced X-ray emission (PIXE). Trace element concentrations are also measured by inductively coupled plasma atomic emission spectroscopy for comparison. The relationship between the trace element content and the mechanism of serpentine formation is discussed. The results indicate that Type I jade has a small amount of Ni in it and almost no Cr and Co while significant amount of Cr, Co and Ni was found in Type II jade. Thus, this could be used to distinguish the two kinds of serpentine jade formed by different mechanisms.

Ferromagnetic glass ceramics with magnetism and biological activity could be used for magnetic induction hyperthermia. In this study Fe2O3-CaO-SiO2 glass-ceramics were prepared by sol-gel method. The sample was characterized by X-ray diffraction (XRD) and differential thermal analysis (DTA). The results showed that the major phases of the sample are wollastonite and magnetite and the crystallization activation energy of sample is 189.3KJ/mol, which would provide a theoretical basis for the establishment of the optimum process conditions of heat treatment technology.