Large-area ZnO nanorod arrays have been synthesized successfully on a stainless steel grid at a mild growth temperature of around 400 degrees C. The as-grown ZnO nanorods have uniform diameters of about 30-50 nm with approximately 5 nm tips. Patterned growth can be realized by engineering the shape of the grid in the growth. Photoluminescence demonstrates a sharp strong UV peak and a broad green band. The growth method provides a promising way of producing nanorod arrays with good controllability in patterns and morphologies, which will be critical in potential application such as high-efficiency filtering and catalysts.

Apparent molar volumes (V Φ ) of hexane-1,2,3,4,5,6-hexol in aqueous solutions of 1-and 2-propanols were obtained from densities of ternary solutions, accurately measured with a quartz vibrating-tube densimeter at several temperatures in the range from (293.15 to 313.15) K. Refractive indexes (n D ) measurements were also made for hexane-1,2,3,4,5,6-hexol + propanol + water at T ) 298.15 K. The data of V Φ have been used to deduce the limiting partial molar volumes of hexane-1,2,3,4,5,6-hexol (V 0 Φ ) and limiting partial molar volumes of transfer (∆ trs V 0 Φ ) from water to different alcohol solutions at different concentrations. From the values of n D , molar refractive indexes (R D ) were calculated. Then the changes of these parameters were discussed in the light of interaction between solute and solvent and the different locations of the hydroxyl group in propanol isomers.

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Supramolecular 2,3-pyridinedicarboxylate intercalated NiAl-layered double hydroxides (2,3-pyridinedicarboxylate-NiAl-LDHs) has been prepared by direct coprecipitation method. The solid product was found to have a greatly expanded LDH structure. Possible orientation of 2,3-pyridinedicarboxylate between the interlayer region has been proposed. Furthermore, its thermal decomposition process was studied by the use of TG-MS and in situ HT-XRD.

The sulfur-transfer catalyst is widely used to remove the sulfur oxides (SO x ) from the flue gas in the fluid catalytic cracking (FCC) units. This paper reports the influence of the pore structure of the Ce/MgAl hydrotalcite-derived mixed oxides on its SO x pick-up capacity. The Ce/MgAl hydrotalcites precursors were synthesized by the separate nucleation and aging steps (SNAS), and then were calcined in air at 800°C to prepare the Ce/MgAl mixed oxides. And in our preparations, the pore structures of the Ce/MgAl mixed oxides were controlled by modifying the aging time of the hydrotalcites precursors. It is found that with the aging time of 4 to 6 h produced the largest pore volume (the largest total pore volume and the least pore less than 10 nm) and resulted in the largest SO x pick-up capacity. The fluid catalytic cracking (FCC) process, a petroleum refining process applied commercially on a very large scale, is one of the major sources of SO x emission. In order to meet the increasing stringent environmental regulations, most refineries used the sulfur-transfer catalysts in their FCC units [1][2][3][4][5]. So far, Ce/MgAl hydrotalcite-derived mixed oxides system has been the most popular one for the sulfur-transfer catalyst in the FCC processing. Yet previous studies in this field have mainly focused on the respective and/or synergistic role of their chemical composition [3,[6][7][8][9][10][11][12] as well as the preparation processes. For example, we reported the preparation of Ce/MgAl hydrotalcite-derived mixed oxides prepared by impregnation, conventional coprecipitation and SNAS (separate nucleation and aging steps) approaches and following by their properties studies. It was confirmed that sample prepared via the SNAS method possessed both the highest rate and the largest capacity during the SO x pick-up process [13]. However, the catalyst's pore structure, which is actually one important factor in controlling the catalyst's performance in SO x pick up capacity, have not been studied carefully.In this work, the SNAS method was applied in the synthesis of the Ce/MgAl hydrotalcites precursors, followed by the aging process with different time. And finally the mixed oxides were gotten by calcination. Both the precursors and the catalysts were characterized carefully and the relationship between the SO x pick-up capacity of the catalysts and their pore size distributions was studied. Experimental Preparation of Ce/MgAl hydrotalcite-derived mixed oxides by SNAS methodCe/MgAl hydrotalcite precursorss were synthesized by coprecipitation using separate nucleation and aging steps (SNAS) in our laboratory [14]. Then, the precursors were