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用聚乙二醇（ＰＥＧ）和乙醇溶剂反沉淀法制备颗粒直径９．１～８６０ｎｍ的锂铁氧体纳米晶．Ｘ射线衍射分析表明这些纳米晶是纯ＬｉＦｅ５Ｏ８．用振动样品磁强计测量不同温度下的磁化和退化曲线，得出其比饱和磁化强度和矫顽力随纳米晶颗粒直径和温度的变化．利用趋近饱和定律求出不同温度下，样品的有效各向异性常数ＫＥ，发现颗粒直径为９．１ｎｍ的ＬｉＦｅ５Ｏ８纳米晶的ＫＥ比其大块材料的磁晶各向异性常数Ｋ１几乎增大１０倍．利用均匀转动反磁化和混合矫顽力模型计算纳米晶的不同温度下的矫顽力，得出与实验相符的结果
Lithium ferrite nanocrystals with diameter 9.1 ~ 860nm were prepared by reverse precipitation with polyethylene glycol (PEG) and ethanol. X-ray diffraction analysis shows that these nanocrystals are pure LiFe5O8. The magnetization and degeneration curves at different temperatures were measured with a vibrating sample magnetometer, and the change of the specific saturation magnetization and coercivity with the diameter and temperature of the nanocrystalline particles was obtained. The effective anisotropy constant KE of the sample at different temperatures is obtained by the approach of saturation, and the KE of the LiFe5O8 nanocrystal with the particle diameter of 9.1nm is found to be almost 10 greater than the magnetic crystal anisotropy constant K1 of the bulk material Times The coercivity at different temperatures of the nanocrystals was calculated by using the uniform rotational anti-magnetization and mixed coercive force model, and the experimental results were obtained