Ningbo ninggang permanent magnetic materials ltd . is set up in 1987 , specially exploit and manufacture smco , ndfeb magnets and various of magn . . . . . 宁波宁港永磁材料有限公司建于1987年，专业从事开发与生产钐钴钕铁硼等磁性材料及各种应用器件。
3.
Ningbo ninggang permanent magnetic materials ltd ( ngyc ) . is set up in 1987 , specially exploit and manufacture smco , ndfeb magnets and various of magn . . . . . 宁波宁港永磁材料有限公司建于1987年，专业从事开发与生产钐钴、钕铁硼等磁性材料及各种应用器件。
4.
Abstract : by experiment , the effect of b2o3 on high - temperature performance of magn esium refractory was analysed systematically . the mechanism of boron contaminatio n in the process of magnesium oxide synthesis with bittern or sea water and the way of preparing magnesium oxide with low boron content were described 文摘:通过实验，系统分析和阐述了b2o3对镁质耐火材料高温性能的影响，卤(海)水合成氧化镁过程中硼污染的机理，以及制取低硼氧化镁的有效途径。
