中文摘要：

以粒径为700nm的球形Fe304为晶种，将晶种加入到含有FeS04·7H20、FeCl3·6H2O与尿素的混合溶液中，在磁场诱导下制备链状Fes04。研究了磁场强度、晶种添加量、分散剂聚乙烯吡咯烷酮（PVP）质量浓度以及反应时间对产品形貌的影响。研究结果表明，随着磁场强度的增大、晶种量的增加，链状粒子数目显著增多；适量的PVP能使链状粒子分散平行排列。合成链状Fe3O4粒子的最佳工艺条件为磁场强度0．35T，晶种用量10％，PvP质量浓度7．5g／L，反应18h。磁性能测试表明，该链状Fe304粒子具有亚铁磁性，磁饱和强度为72．3emu／g，矫顽力为381Oe。

英文摘要：

One-dimensional chain-like magnetite particles were prepared by a seed-mediated growth method un- der the induction of magnetic field. The seeds, 700nm in size, were added into the mixture of FeSO4 · 7H20,FeCIa · 6H20 and urea. The effects of magnetic field intensity, seed amount, dispersant polyvinylpyrrolidone（PVP） concen- 0 tration and reaction time on the morphology of samples were discussed. The results showed that the number of chain- like particles increased with an increase of both magnetic field and seed amount. Appropriate PVP was favorable to ob- tain parallel chains. The optimum conditions for preparation of chain-like particles are 0. 35T magnetic field, 10% seed, 7. 5g/L PVP and 18h reaction time. Magnetic measurements reveal that magnetite chains are ferromagnetic with a saturation magnetization of 72.3emu/g and coercivity of 381Oe.