中文摘要：

采用溶胶-凝胶法制备了多晶La0.6Sr0.05Na0.35MnO3粉体样品,用固相反应法制备了La0.6Sr0.05Na0.35MnO3＋xAgNO3（x=0.08,0.16）的粉体样品,块体于1 673K烧结得到.结果在样品中发现了Ag和Mn3O4相,对母体样品的晶格常数和晶胞体积都有微小影响;样品的居里温度随掺杂AgNO3含量的增加而增加;在1.8T磁场下La0.6Sr0.05Na0.35MnO3＋0.16AgNO3的块体材料在283K出现磁电阻峰值,为27%;La0.6Sr0.05Na0.35MnO3＋0.08AgNO3块体也在283K左右出现峰值,为32%,在210～260K时磁电阻随温度变化不大.

英文摘要：

La_（0.6）Sr_（0.05）Na_（0.35）MnO_3 polycrystalline sample was synthesized by sol-gel method.The La_（0.6）Sr_（0.05）Na_（0.35）MnO_3 ＋xAgNO3（x=0.08,0.16） was prepared by conventional solid state reaction method and the palletized samples were heated at 1 673K.Ag and Mn3O4were found in the samples,and thus they had a minor impact on the lattice constant of the parent sample and the cell volume;Curie temperature increased with the doping of AgNO3content increases;Under an applid filed of 1.8T,there is a MR maximum 27% of La_（0.6）Sr_（0.05）Na_（0.35）MnO_3＋0.16AgNO 3 at 283K;and a MR maximum 32% of La 0.6 Sr 0.05 Na 0.35 MnO3＋0.08AgNO3 at 283K.At 210～260K,there is little change in magnetoresistance of these two samples.So temperature stability of magnetoresistance is improved,which supplies a new method to improve magnetoresistance and temperature stability of magnetoresistance.