Although, post annealing is an efficient way to annihilate/restructure deficiencies in self-assembly (SA) ZnO nanorods (ZNRs), the detailed investigation about the surface properties of annealed SA-ZNRs is a long standing issue and the major discrepancy is mainly due to single step annealing. We demonstrate the strategic two step annealing process to create reliable structural configuration in SA-ZNRs during the first round of annealing at 800 °C in vacuum (VA process), and create intrinsic defects in the second step of annealing in oxygen rich atmosphere (OA process) to correlate the formation of the defects related to green/orange-red emission. SA-ZNRs annealed in VA-OA processes reveal positive correlations between the oxygen flow rate and formation of oxygen interstitials (Oi) and zinc vacancies (VZn). The OA-VA processes exhibit the relation of residual Oi and additional Vo. According to VA-OA and OA-VA processes, we propose that the green emission in ZnO annealed in oxygen poor/rich condition is mainly due to the formation of Vo/VZn and annealing at oxygen rich condition creates Oi that lead to strong orange-red emission. Rather than O1s, we propose a reliable method by considering the peak shift of Zn2p in XPS to inspect the ZnO matrix, which has good interdependence with the characteristics of PL.

Post-annealing treatment is a necessary process to create/eliminate/repair defects in self–assembly (SA) metal oxide by providing enough thermal energy to the O atoms to overcome the migration energy barrier in ZnO. The height of migration energy barrier is dependent on the depth from the surface, which is hard to be estimated by theoretical calculations, as well as the optical analyses. SA ZnO nanorods (ZNRs) have high surface-to-volume ratio to provide complete picture between the optical and surface properties obtained by photoluminescence (PL) and ultraviolet/X-ray photoemission spectroscopy (UPS/XPS), which is used to investigate the evolution of structure and chemical states of the surface layers to reveal mutual agreement on all observations in PL, XPS, and UPS. We demonstrate variation of the surface structure of SA-ZNRs by scanning over a range of annealing temperatures and time to regulate the structure variation of SA-ZNRs, and their optical analyses agrees well with PL, XPS and UPS, which indicates the dependence of migration energy barriers on the depth from the surface of ZNR. The results reveal the well ZNRs formed at 570 °C and the further oxidation process and the formation of hydroperoxide on the Zn-rich surface of ZNRs at 640 °C.

The theoretical composition was made from MgO-rich MgAl2O4 (MR66) and alumina powder. The static crucible method was used to study alkali-resistance of the block samples. It has been observed that alkali steam permeated into the hole and reacted with corundum particles that produced β-Al2O3 by means of XRD, SEM and EDS. It led to volume expansion, cracks and melting erosion of corundum particles. The specimen of the 32% content of MgO has good physical and chemical properties and excellent alkali erosion performance. So the specimen is suitable for oxy-fuel combustion for glass melting furnace.

Unfired specimens were made with different aluninum content (0,2%,4%,6%,8%) respectively ,using high pure magnesia , magnesia-spinel and Aluninum as the main raw material. Unfired specimens were treated under the condition:110°C×24h drying,then 300°C×6h heating treatment.The properties and microstructure of the specimens were analyzed to investigate the reaction mechanism of these speciments and RH refinery slag.The result are shown that the addition of aluninum improves cold crushing strength of specimens,reaching to 63Mpa. The specimen with aluninum content of 8% shown the best slag resistance. The reaction mechanism between aluninum-magnesia-spinel complosite material and RH slag is different from magnesite-chrome brick. The major penetration element is Ca, and the Ca elment penetrated into the matrix reacts with corundum turning out a CA2 protective layer which can stop penetrating of slag.

Using alumina-rich MgAl2O4 spinel AR78 and 97 fused magnesite as raw materials, brine as the binder, magnesia alumina spinel bricks close to theoretical composition have been prepared. The phase composition and microstructure of the specimens were analyzed and characterized. The alkali resistance property of specimens was researched using static crucible method. The erosion mechanism of alkali vapor to specimens was studied by XRD, SEM and EDS. The results show that: (1) The alkali resistance property of MgAl2O4 spinel bricks were improved obviously when the addition of magnesite is more than 7%. (2) The alkali resistance property of MgAl2O4 spinel bricks is the best when the addition of magnesite is 10.3%.