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A seed-induced preparation method was developed to synthesize ZSM-5 crystals, in which two different kinds of ZSM-5 crystals were used as seeds. The different preparation methods for seeds led to the difference in the morphology and Al distribution. The results showed that the synthesized zeolites showed nanosheet morphology regardless of the types of seeds. However, the different types of seed led to the difference of synthesized zeolites in the pore structure, acid properties, and defect sites. Catalytic activity for the methanol to propylene (MTP) reaction of sample synthesized from sheet-like seed was better than that synthesized from spherical seed. On the contrary, the further hydrothermal treated sample induced by spherical seed demonstrated much a longer lifetime and higher propene selectivity in the MTP reaction compared to that induced by sheet-like seed. Its excellent catalytic performance can be attributed to the proper acidity, faster diffusion rate, and fewer framework defects after hydrothermal treatment.

A series of HZSM-5/MCM-41 composite molecular sieves (HZM-Ns (x)) were prepared by employing nano-ZSM-5 zeolites with the SiO 2 /Al 2 O 3 ratios (x) of 50, 100 and 150 as the source. These materials were characterized by X-ray diffraction, Fourier transform infrared spectroscopy, scanning electron microscopy, energy dispersive spectroscopy, transmission electron microscopy, N 2 adsorptiondesorption measurement, and NH 3 temperature-programmed desorption. The catalytic cracking of endothermic hydrocarbon fuels over the HZM-Ns with ndecane as model was evaluated at atmospheric pressure and 500°C. The effect of the parent zeolite, mesopore and SiO 2 /Al 2 O 3 ratio on the structure, acidity, and catalytic performance of HZM-Ns was investigated. The HZM-Ns exhibited a skeletal matrix with nano-sized HZSM-5 particles (200-300 nm) with a controllable acidity well dispersed in and microporous-mesoporous hierarchical pores. The mesoporous structure improved the diffusion of the reactants and products in the pores, and the HZSM-5 nanoparticles uniformly dispersed in the MCM-41 matrix supplied a proper acidity, shorter channels, and a higher specific surface area for reaction. These resulted in a high catalytic activity, a high selectivity to light olefins and a long lifetime for n-decane catalytic cracking. The HZM-N (150) exhibited the excellent conversion, a high selectivity to light olefins and a long lifetime due to low diffusion resistance, high specific surface area, and appropriate acid distribution and strength, with the increasing SiO 2 / Al 2 O 3 ratio.

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26The wettability and hydrophobicity of super-hydrophobic (SH) meshes is greatly influenced 27 by their topographic structures, chemical composition and coating process. In this study, the 28 properties of copper and stainless steel meshes, coated with super-hydrophobic electrolessly 29 deposited silver were investigated. A new method to test the pressure resistance of super-30hydrophobic mesh was applied to avoid any deformation of mesh. Results showed that SH 31 copper mesh and SH stainless steel meshes with the same pore size have almost the same 32 contact angle and the same hydrophobicity. SH copper mesh with a pore size of 122 μm can 33 resist water pressure of 4900 Pa and a decrease of pore size of mesh can increase the pressure 34 resistance of SH copper mesh. The SH copper mesh modified with 0.1M HS(CH2)10COOH 35 solution in ethanol has a controllable water permeation property by simply adjusting the pH of 36 water solution. SH copper mesh shows super-oleophilicity with organic solvents and so with a 37 water contact angle of 0° and it can be an effective tool for organic solvents/water separation. 38The separation efficiency of SH copper mesh for separating mixtures of organic solvent and 39 water can be as high as 99.8%. 40 41