For heat, there is one silver cylinder-shaped grate, perforated evenly with holes the size of children's fingers.
取暖用的是一个银色圆柱状取暖炉，上面均匀地分布着孩子手指大小的小孔。
The first grate has double spherical nets with the same center and outside the second one there is a shield cylinder to make electron congregate.
它采用四极枪结构，两个栅极，第一栅极采用双层同心球面网，第二栅极外还添加了屏蔽筒。
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