Research progress of permanent ferrite magnet materials

Permanent ferrite magnet materials are extensively employed due to their exceptional magnetic properties and cost-effectiveness.The fast development in electromobile and household appliance industries contributes to a new progress in permanent ferrite materials.This paper reviews the deveolpement and progress of permanent ferrite magnet industry in recent years.The emergence of new raw material,the advancement of perparation methods and manufacturing techniques,and the potential applications of permanent ferrite materials are introduced and discussed.Specifically,nanocrystallization plays a crucial role in achieving high performance at a low cost and reducing reliance on rare earth resources,and therefore it could be a promising development trendency.

老年性白内障患者角膜散光状态的初步分析

目的:分析老年性白内障患者角膜散光状态的分布情况。方法对84例(149眼)老年性白内障患者采用IOLMaster测量角膜散光情况。对患者角膜散光度数的大小,散光类型的分布情况,眼轴与角膜散光度数的相关性等进行分析。结果患者平均年龄(72.16±3.78)岁,角膜散光的平均值为0.96D(0.05D-4.96D),角膜散光≥1.0D的占63.1%,其中逆规性散光占40.9%。结论角膜散光检查分析对老年性白内障手术切口的选择及联合角膜散光矫正术有一定参考和指导意义。