Fused materials from ZrO2 stabilized by CaO or MgO, or the combined additive consisting of CaO and MgO are made. With using chemical, petrographic, X-ray phase and electron microscopic researches the main characterist...Fused materials from ZrO2 stabilized by CaO or MgO, or the combined additive consisting of CaO and MgO are made. With using chemical, petrographic, X-ray phase and electron microscopic researches the main characteristics of these materials are determined. It is shown that, the materials of all compositions have low water absorption; they are characterized by equal struc-ture. The materials stabilized by the combined additive consisting of CaO and MgO are presented by generally the cubic phase and a small amount of tetragonal and monoclinic ZrO2 phases. Depending on CaO： MgO ratio in the materials the tetragonal ZrO2 phase settles down in a cubic matrix in the form of separate grains, and sites of net like structure in the form of a ＂woven＂ interlacing （2.9% of CaO and 2. 6% of MgO ）. An influence of the above mentioned fused stabilized ZrO2 materials and quantity of monoclinic zirconia, on the forming of zirconia mix on a phosphate bond and properties of＂ .fired samples is studied. The samples from mix based on ZrO2 stabilized by the combined additive consisting of 2.9% CaO and 2.6% MgO with 20% of monoclinic Zr02 are characterized by the highest properties： after .firing at 1 580 ~C open porosity of 14. 3% - 14. 8%, apparent density of 4. 67 -4. 69 g · cm^-5, cold crushing strength of 62 - 68 MPa, thermal shock resistance （ 1 300℃←→air） of 15 thermal cycles, linear growth of 0. 2%. The manufacturing technology of powders mix-ture for ramming mix based on the new fused material .from ZrO2 stabilized by the combined additive is developed and its production is mastered. From this mixture the large-size, shaped products on the phosphate bond are made at one carbon black production plant, which are installed in the combustion chamber of the carbon black production reactor.展开更多
A great deal of attention has been focused on discharge plasma as it can rapidly decompose N2O without additives,which is not only a kind of greenhouse gas but also a kind of damages to the ozone layer.The thermal equ...A great deal of attention has been focused on discharge plasma as it can rapidly decompose N2O without additives,which is not only a kind of greenhouse gas but also a kind of damages to the ozone layer.The thermal equilibrium plasma is chosen to combine with catalysts to decompose N2O,and its characteristics are analyzed in the present paper.The results indicate that NO and NO2 were formed besides N2 and O2 during N2O decomposition when N2O was treated merely by discharge plasma.Concentration of NO declined greatly when the discharge plasma was combined with catalysts.Results of Raman spectra analysis on CeO2,Ce（0.75）Zr（0.25）O2and Ce（0.5）Zr（0.5）O2 imply that the products selectivity has been obviously improved in discharge plasma decomposing N2O because of the existence of massive oxygen vacancies over the composite oxide catalysts.展开更多
文摘Fused materials from ZrO2 stabilized by CaO or MgO, or the combined additive consisting of CaO and MgO are made. With using chemical, petrographic, X-ray phase and electron microscopic researches the main characteristics of these materials are determined. It is shown that, the materials of all compositions have low water absorption; they are characterized by equal struc-ture. The materials stabilized by the combined additive consisting of CaO and MgO are presented by generally the cubic phase and a small amount of tetragonal and monoclinic ZrO2 phases. Depending on CaO： MgO ratio in the materials the tetragonal ZrO2 phase settles down in a cubic matrix in the form of separate grains, and sites of net like structure in the form of a ＂woven＂ interlacing （2.9% of CaO and 2. 6% of MgO ）. An influence of the above mentioned fused stabilized ZrO2 materials and quantity of monoclinic zirconia, on the forming of zirconia mix on a phosphate bond and properties of＂ .fired samples is studied. The samples from mix based on ZrO2 stabilized by the combined additive consisting of 2.9% CaO and 2.6% MgO with 20% of monoclinic Zr02 are characterized by the highest properties： after .firing at 1 580 ~C open porosity of 14. 3% - 14. 8%, apparent density of 4. 67 -4. 69 g · cm^-5, cold crushing strength of 62 - 68 MPa, thermal shock resistance （ 1 300℃←→air） of 15 thermal cycles, linear growth of 0. 2%. The manufacturing technology of powders mix-ture for ramming mix based on the new fused material .from ZrO2 stabilized by the combined additive is developed and its production is mastered. From this mixture the large-size, shaped products on the phosphate bond are made at one carbon black production plant, which are installed in the combustion chamber of the carbon black production reactor.
基金supported by National Natural Science Foundation of China(No.50677026)the Applied Basic Research Program of Wuhan,China(No.2015060101010068)
文摘A great deal of attention has been focused on discharge plasma as it can rapidly decompose N2O without additives,which is not only a kind of greenhouse gas but also a kind of damages to the ozone layer.The thermal equilibrium plasma is chosen to combine with catalysts to decompose N2O,and its characteristics are analyzed in the present paper.The results indicate that NO and NO2 were formed besides N2 and O2 during N2O decomposition when N2O was treated merely by discharge plasma.Concentration of NO declined greatly when the discharge plasma was combined with catalysts.Results of Raman spectra analysis on CeO2,Ce（0.75）Zr（0.25）O2and Ce（0.5）Zr（0.5）O2 imply that the products selectivity has been obviously improved in discharge plasma decomposing N2O because of the existence of massive oxygen vacancies over the composite oxide catalysts.
