在邮票的票面上凿出有关文字或图形的孔洞，称凿孔，主要是用以标明特殊用途及防盗，如公文凿孔、欠资凿孔、样票凿孔、公司略字凿孔及防盗凿孔等。
与在电极上凿孔不同的是，他们在电极上覆盖一层碳纳米管，每个只有5纳米(十亿分之一米)宽。
Instead of digging holes in the electrodes, they are coating them with a forest of carbon nanotubes, each five nanometres (billionths of a metre) wide.
在水尚未流经缆绳前，研究团队无法确定，融化的水是会流入粒雪中，还是会聚积在钻头的周围。如果是后者，将会使凿孔因冻结而封闭。
Until water flowed through the tether, the team could not tell if the meltwater was draining into the firn or accumulating around the drill, which could freeze the borehole shut.
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