We demonstrate the preparation of hierarchical porous structure composite particles containing sodalite cores,and outer zeolitic imidazolate framework-8 (ZIF-8) shells. The synthesis involved first synthesis of sodalite zeolites by hydrothermal reaction from alkali-activated kaolin with polyacrylamide acting as structure-directing agent, and followed by the directly in stu growth ZIF-8 nanoparticles shells over the sodalite microparticles. The resulting core shell structure ZIF-8@Sodalite composites were characterized by powder X-ray diffraction (PXRD) and scanning electron microscope (SEM) Nitrogen adsorption, Fourier Transform infrared spectroscopy (FTIR), hermogravimetry analysis (TGA) and differential thermal analysis (DTA). SEM picture showed ZIF-8 particles adhesive on the surface of Sodalite. The composites have a nitrogen sorption capability as high as around 120 cm3/g and a BET surface area of over 328.86 m2/g, which are much higher than that of pure sodalites. The weight percentage of ZIF-8 loading on sodalite external surface can be calculated to be approximately 12% by mass loss on the TG curves. It is believed that the designed ZIF-8@Sodalite particles could broaden the application areas of zeolites in heterogeneous catalysis.
The quality of the kaolin is always measured by iron contents since this element gives undesirable reddish color which limits the usage of this type of minerals. Reducing the iron contents to increase the value of kaolin by bleaching process is investigated. The effects of factors which can improve the whiteness of kaolin have been studied. The dosage of sodium dithionite, pH value, solid-to-liquid ratio and reaction time were chose as factors based on mono-factor experimental results. Orthogonal experiments were carried out and the optimum processing conditions of the reductive bleaching were obtained as the dosage of sodium dithionite 3%, pH 2, solid-to-liquid ratio 1:3 and reaction time 45min. After bleaching process described above, we obtained a great improvement in the whiteness from 69.93% to 81.31% and a decrease of Fe2O3 content from 0.52% to 0.40% of the kaolin.
Three kinds of porous materials were synthesized using calcined kaolin with small molecular amine templates by hydrothermal methods. Sodium silicate was chose as silicon sources and three different amines namely acetamide, ethylenediamine and hexamethylenetetramine were chose as the organic templates. The physicochemical properties of obtained samples were characterized by X-ray diffraction, infrared spectrum and scanning electron microscopy.Crystallinity and morphology of samples were investigated. The influence of small molecular amines templates was discussed.
The effect of slag treatment with Copper addition in silicon purification by metallurgical methods was examined in this paper. The microstructures and contents of Si-Cu alloy after slag refining were investigated by XRD and ICP, respectively. The majority phases in the Si-Cu alloy were Cu3Si and Si. The partition ratio of boron (LB) between slag and silicon was studied with and without Cu addition. Experimental results show that slag treatment with Cu addition can improve the LBin CaO-SiO2-CaF2slag system, where a maximum boron removal ratio of 85% could be achieved.
The e-government is an important content of the national government informational progress, it has far-reaching significance, it's security also faces many threats and challenges, it has frequent occurrence of security incidents. To control such a huge security risk and avoid huge losses, and protect the security of e-government, this paper constructs the e-government security plan system, in the design of the system, the security protection of e-government system and institution, emergency response system and mechanism are made as a major part of the design, security protection include security management and technology, and quantitatively analyze the security services performance assessment standards, and detailedly design security services performance assessment algorithm, and the algorithm is integrated into the security management and is verified by an instance, the plan system can do a better safety risk assessment, can control certain risks and losses.
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