Discuss the differences between children's first language acquisition and adults'second language acquisition from four aspects:age, motivation, environment, learning process and content in order to help adults...Discuss the differences between children's first language acquisition and adults'second language acquisition from four aspects:age, motivation, environment, learning process and content in order to help adults to learn L2 more efficiently by applying some of the knacks for L1 to L2.展开更多
文摘Discuss the differences between children's first language acquisition and adults'second language acquisition from four aspects:age, motivation, environment, learning process and content in order to help adults to learn L2 more efficiently by applying some of the knacks for L1 to L2.
文摘以MnO2,Ca(OH)2和La(OH)3为反应原料,在惰性气氛、低温(500℃)熔融KOH体系中合成了具有菱形钙钛矿结构Ca,K共掺杂的La0.64Ca0.25K0.11MnO3纳米材料,并对Mn的价态及磁学性能等进行了讨论.X射线光电子能谱(XPS)分析结果表明,La0.64Ca0.25K0.11MnO3纳米材料中的Mn具有三重混合价态,其零场冷却低温磁化率曲线表现出顺磁-铁磁转变,居里温度(Tc)为280 K.
