1·Moreover, corundum and periclase have not been detected in space dust before.
而且，此前在太空尘埃中还未侦测到刚玉和方镁石。
2·A comparative test of standard clay bricks, high alumina bricks, silica bricks and periclase bricks which were used as checkers in upper parts of regenerators has been conducted.
本文介绍了用粘土砖、高铝砖、硅砖和方镁石砖作蓄热室上层格子体进行对比试验的情况。
3·The hydration of periclase in the magnesia is the theoretical basis for its expansion.