Carbothermal reduction of alumina into aluminium oxynitride(AlON) spinel in a flowing nitrogen atmosphere was studied.The effects of Al2O3/C ratio temperature,soaking time,heating rate molding pressure of samples,and ...Carbothermal reduction of alumina into aluminium oxynitride(AlON) spinel in a flowing nitrogen atmosphere was studied.The effects of Al2O3/C ratio temperature,soaking time,heating rate molding pressure of samples,and nitrogen flow rate on reactions were investigated.Then the stability of AlON was elucidated and AlON wa confirmed as an intermediate compound in reduction of alumina.展开更多
The slag corrosion resisance of corundum-spinel castable has been increased by adding aluminum oxynitride spinel (AlON) powder ,Its results show that corrosion resistance of this castable is remarkably imroved when 3 ...The slag corrosion resisance of corundum-spinel castable has been increased by adding aluminum oxynitride spinel (AlON) powder ,Its results show that corrosion resistance of this castable is remarkably imroved when 3 wt% of the AlON powder added ,It was assumed that solid solution between aluminum oxynitride and magnesium aluminate spinel occurred to prevent the slag penetration into castable and increase the corrosion resistance of the corundum-spinel castable However,the experimental resultsd suggest such castable containing AlON powder be much more appropriate to be used in non-oxidation condition rather than in oxidation atmosphere.展开更多
The high-purity AlON ceramics,AlON/Al2O3 and AlON/AlN multiphase ceramics were prepared by pressureless sintering under nitrogen-based atmosphere with raw materials of Al2O3,AlN and Al powders. The compositions of the...The high-purity AlON ceramics,AlON/Al2O3 and AlON/AlN multiphase ceramics were prepared by pressureless sintering under nitrogen-based atmosphere with raw materials of Al2O3,AlN and Al powders. The compositions of the phase were determined by XRD,the fracture appearance was analyzed by SEM. The results indicate:the aluminum oxynitride phase in the AlON ceramics and other multiphase ceramics exist in the form of Al5O6N,whose solid-solution zone is 33.4%(mole fraction) AlN belonging to spinel structures. The average grain size of high-purity AlON is about 3 μm. The grain boundary is smooth without other phases. The density is 2.82 g/cm3,the microhardness(10 N) and about bending strength are 1 470 MPa and 94 MPa,respectively.展开更多
The photocatalytic activity of cobalt octakis（butylthio） porphyrazine（CoPz（BuS）8） was assessed through photodegradation of the dye rhodamine B（RhB） in water under irradiation with a Xe lamp and aerated conditi...The photocatalytic activity of cobalt octakis（butylthio） porphyrazine（CoPz（BuS）8） was assessed through photodegradation of the dye rhodamine B（RhB） in water under irradiation with a Xe lamp and aerated conditions.The photocatalytic activity of CoPz（BuS）8 loaded on Al2O3 or SiO2@Fe3O4nanoparticles or coordinated with an axial azide ligand was also investigated.The results demonstrated that the photocatalytic activity of CoPz（BuS）8 loaded on Al2O3 was higher than that loaded on SiO2@Fe3O4.The kinetic curves of RhB degradation in aqueous solutions at different pH indicated the pseudo first-order kinetics of the reaction.The highest degradation rate for CoPz（BuS）8 loaded Al2O3 at pH = 4 after 160 min was 84.6%.However,the advantages of easier separation and recycling as well as the ability to terminate the reaction at any time for the CoPz（BuS）8 loaded SiO2@Fe3O4 cannot be ignored.When electron-rich NaN3 was coordinated with CoPz（BuS）8 as an axial ligand and loaded on Al2O3,the resulting catalyst produced more active oxygen species such as O2^- and HO· to promote the quicker degradation of RhB than that by the other catalysts.For the N3-coordinated CoPz（BuS）8 loaded on Al2O3,the reactions at pH = 4 and 7 distinctly deviated from first-order kinetics,and the degradation rate reached 77.6%after 80 min at pH = 4.展开更多
文摘Carbothermal reduction of alumina into aluminium oxynitride(AlON) spinel in a flowing nitrogen atmosphere was studied.The effects of Al2O3/C ratio temperature,soaking time,heating rate molding pressure of samples,and nitrogen flow rate on reactions were investigated.Then the stability of AlON was elucidated and AlON wa confirmed as an intermediate compound in reduction of alumina.
文摘The slag corrosion resisance of corundum-spinel castable has been increased by adding aluminum oxynitride spinel (AlON) powder ,Its results show that corrosion resistance of this castable is remarkably imroved when 3 wt% of the AlON powder added ,It was assumed that solid solution between aluminum oxynitride and magnesium aluminate spinel occurred to prevent the slag penetration into castable and increase the corrosion resistance of the corundum-spinel castable However,the experimental resultsd suggest such castable containing AlON powder be much more appropriate to be used in non-oxidation condition rather than in oxidation atmosphere.
基金Project(2001AA333040) supported by the High-tech Research and Development Program of China
文摘The high-purity AlON ceramics,AlON/Al2O3 and AlON/AlN multiphase ceramics were prepared by pressureless sintering under nitrogen-based atmosphere with raw materials of Al2O3,AlN and Al powders. The compositions of the phase were determined by XRD,the fracture appearance was analyzed by SEM. The results indicate:the aluminum oxynitride phase in the AlON ceramics and other multiphase ceramics exist in the form of Al5O6N,whose solid-solution zone is 33.4%(mole fraction) AlN belonging to spinel structures. The average grain size of high-purity AlON is about 3 μm. The grain boundary is smooth without other phases. The density is 2.82 g/cm3,the microhardness(10 N) and about bending strength are 1 470 MPa and 94 MPa,respectively.
基金supported by National Natural Science Foundation of China (20977115, 21272281)Natural Science Foundation of Hubei Province (2014CFB919)the Science and Technology Plan Innovation Team of Wuhan City (2015070504020220)~~
文摘The photocatalytic activity of cobalt octakis（butylthio） porphyrazine（CoPz（BuS）8） was assessed through photodegradation of the dye rhodamine B（RhB） in water under irradiation with a Xe lamp and aerated conditions.The photocatalytic activity of CoPz（BuS）8 loaded on Al2O3 or SiO2@Fe3O4nanoparticles or coordinated with an axial azide ligand was also investigated.The results demonstrated that the photocatalytic activity of CoPz（BuS）8 loaded on Al2O3 was higher than that loaded on SiO2@Fe3O4.The kinetic curves of RhB degradation in aqueous solutions at different pH indicated the pseudo first-order kinetics of the reaction.The highest degradation rate for CoPz（BuS）8 loaded Al2O3 at pH = 4 after 160 min was 84.6%.However,the advantages of easier separation and recycling as well as the ability to terminate the reaction at any time for the CoPz（BuS）8 loaded SiO2@Fe3O4 cannot be ignored.When electron-rich NaN3 was coordinated with CoPz（BuS）8 as an axial ligand and loaded on Al2O3,the resulting catalyst produced more active oxygen species such as O2^- and HO· to promote the quicker degradation of RhB than that by the other catalysts.For the N3-coordinated CoPz（BuS）8 loaded on Al2O3,the reactions at pH = 4 and 7 distinctly deviated from first-order kinetics,and the degradation rate reached 77.6%after 80 min at pH = 4.
