Applying pump pressure then activates a sliding collar that opens access ports, enabling circulation across the upper casing interval.

然后施加泵压，使滑动箍启动，于是使进入口开启，从而能够穿过套管上段进行循环。

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China's shipping industry has lobbied against such ships, fearing they may strengthen Vale's dominance on the dry-bulk market and China's Ministry of Transport has restricted their access to its ports.

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Under the sanctions, five neighboring nations will close their borders to landlocked Mali except for humanitarian purposes and deny the nation access to their ports, freeze its accounts in regional banks and suspend its participation in cultural and sporting events.

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Under the sanctions, five neighboring nations were to close their borders to landlocked Mali except for humanitarian purposes and deny the nation access to their ports, freeze its accounts in regional banks and suspend its participation in cultural and sporting events.

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