Materials which have magnetic properties similar to iron are ferromagnetic.具有类似于铁那样的磁性的材料就是铁磁物质.A number of rather exotic ferromagnetic materials have been studied to this end.为此,研究了许多颇为奇特的铁磁材料.It is sometimes difficult ...
内置有断路器，防止设备过载。There is an internal circuit breaker to protect the instrument from overload.断路器一般浸在油罐内.The circuit - breaker is generally immersed in a tank of oil.他们围住了他,非要关掉断路器.They had him surrounded and were determine...