Glass bead blasting is acceptable. Steel shot blasting is not acceptable.

可以喷玻璃砂，不可喷钢丸。

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A course material used in blast cleaning, such as sand, steel shot, glass beads or plastics.

用于喷抛清理一种流动材料，例如砂子、钢丸、玻璃珠或塑胶制品。

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Blastfurnace slag, expanded clay, broken brick and steel shot may be used where appropriate.

炉矿渣，陶粒，碎砖和钢丸也可在适当的地方使用。

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Boehner's spokesman, Michael Steel, shot back that the plan B proposal gave Democrats what they wanted -- higher tax rates on millionaires.

CNN: Obama, Boehner remain at odds on verge of fiscal cliff

Boehner's spokesman, Michael Steel, shot back that the plan B proposal gave Democrats exactly what they wanted -- higher tax rates on millionaires.

CNN: Boehner proposes short-term tax fix; Democrats say no

It is possible that there is a ring of steel just out of shot, but it seems that the students only close in on the police after the pepper spraying, rather than before, and then pull back voluntarily to allow the officers to reach the safety of their support.

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