采用柠檬酸络合燃烧法制备了纳米钙钛矿型复合氧化物 AMnO_3(A 为 La,Ce,Pr,Nd)和 La_(0.8)M_(0.2)MnO_3(M 为 K,Cs,Sr)催化剂。采用 X 射线衍射、H_2-程序升温还原和扫描电子显微镜等方法对催化剂试样进行了表征,利用程序升温反应评价...采用柠檬酸络合燃烧法制备了纳米钙钛矿型复合氧化物 AMnO_3(A 为 La,Ce,Pr,Nd)和 La_(0.8)M_(0.2)MnO_3(M 为 K,Cs,Sr)催化剂。采用 X 射线衍射、H_2-程序升温还原和扫描电子显微镜等方法对催化剂试样进行了表征,利用程序升温反应评价了催化剂用于同时消除柴油机尾气中炭颗粒和 NO 的催化活性。研究结果表明,A 位阳离子种类及 A 位掺杂离子的种类对催化剂的活性都有影响。A 位离子为 La 的催化剂(LaMnO_3)活性最好;用低价金属离子部分取代 A 位离子,催化剂活性得到改善,其中以K离子取代效果最好;LaMnO_3和 La_(0.8)K_(0.2)MnO_3催化剂的炭颗粒燃烧温度范围分别为321～521℃和311～425℃,NO 的转化率分别为7.6%和16.4%。展开更多
A new dinucleating 36 membered octoazadiphenol macrocyclic ligand, 3,6,9,12,20,23,26,29 octoaza 35,36 dihydroxy 16,33 dimethyl tricyclo hexatriacontane 1(34),14,16,18(36),31,32 hexene, ODTH, was synthesized by NaBH4 h...A new dinucleating 36 membered octoazadiphenol macrocyclic ligand, 3,6,9,12,20,23,26,29 octoaza 35,36 dihydroxy 16,33 dimethyl tricyclo hexatriacontane 1(34),14,16,18(36),31,32 hexene, ODTH, was synthesized by NaBH4 hydrogenation of the corresponding Schiff base obtained from the condensation between triethylenetetraamine and diformyl p cresol. It was characterized by elemental analysis, IR, UV Vis, 1H NMR and MS. The protonation constants of ODTH and the stability constants of its complexes with Cu?in 1∶1 and 1∶2 system(metal ODTH), have been determined potentiometrically at 25.0℃and μ=0.100 mol·L-1 KCl. Potentiometric equilibrium studies indicate that a variety of deprotonated and protonated mononuclear and dinuclear, as well as hydroxy bridged complexes, form in the pH range 2～12 in aqueous solution. The species distributions and the characteristics of ODTH and the complexes are also described.展开更多
文摘采用柠檬酸络合燃烧法制备了纳米钙钛矿型复合氧化物 AMnO_3(A 为 La,Ce,Pr,Nd)和 La_(0.8)M_(0.2)MnO_3(M 为 K,Cs,Sr)催化剂。采用 X 射线衍射、H_2-程序升温还原和扫描电子显微镜等方法对催化剂试样进行了表征,利用程序升温反应评价了催化剂用于同时消除柴油机尾气中炭颗粒和 NO 的催化活性。研究结果表明,A 位阳离子种类及 A 位掺杂离子的种类对催化剂的活性都有影响。A 位离子为 La 的催化剂(LaMnO_3)活性最好;用低价金属离子部分取代 A 位离子,催化剂活性得到改善,其中以K离子取代效果最好;LaMnO_3和 La_(0.8)K_(0.2)MnO_3催化剂的炭颗粒燃烧温度范围分别为321～521℃和311～425℃,NO 的转化率分别为7.6%和16.4%。
文摘A new dinucleating 36 membered octoazadiphenol macrocyclic ligand, 3,6,9,12,20,23,26,29 octoaza 35,36 dihydroxy 16,33 dimethyl tricyclo hexatriacontane 1(34),14,16,18(36),31,32 hexene, ODTH, was synthesized by NaBH4 hydrogenation of the corresponding Schiff base obtained from the condensation between triethylenetetraamine and diformyl p cresol. It was characterized by elemental analysis, IR, UV Vis, 1H NMR and MS. The protonation constants of ODTH and the stability constants of its complexes with Cu?in 1∶1 and 1∶2 system(metal ODTH), have been determined potentiometrically at 25.0℃and μ=0.100 mol·L-1 KCl. Potentiometric equilibrium studies indicate that a variety of deprotonated and protonated mononuclear and dinuclear, as well as hydroxy bridged complexes, form in the pH range 2～12 in aqueous solution. The species distributions and the characteristics of ODTH and the complexes are also described.
