Nearly 200 years later, men could remain underwater for weeks at a time while crossing the globe on a submarine with a nearly limitless supply of power and the means to destroy several large cities.

将近200年之后，在环游世界时，人们已经可以乘坐潜艇在水下一次呆上几个星期，潜艇的能量也几乎没有限制，其上还有能摧毁数座大型城市的武器。

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Both wet and dry underwater welding operations are presented to repair the burst at the welding seam of large size crossing steel pipe.

介绍了大口径过河钢管接口焊缝爆漏现象，以及湿法和干法水下焊接修复技术。

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