They stacked rocks with center holes (tube or doughnut shaped) from the surface to the deep stone layer as a guide for their drills (similar to today's guide tubes).

管状或中空管状的中心孔从地表到深石岩石层放满石头，以作为铁转的探头，作用类似今天的导管。

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Core memory a type of memory that stores information on magnetically charged doughnut shaped cores. mass storage is currently mostly on magnetic disk drum or taoe rather than core.

磁心贮记器磁心像炸糖环的形状，存贮信息。它是磁化贮记器的一种。大量的信息存贮，现在多采用磁碟、碟鼓或磁带，用磁心贮记器较少。

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The Van Allen belts are two doughnut-shaped rings of charged particles-one nestled inside the other-that encircle our planet.

范艾伦辐射带是由带电粒子组成的两个甜甜圈形状的环状物——其中一个挨靠在另一个内部——环绕着我们地球。

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It isn't the kind of doughnut-shaped, the rich inner and poorer outer, that Paris has.

BBC: London's homeless families could rise by 5,000

Navalny works at a doughnut-shaped conference table, behind drifts of paper and a laptop bristling with memory sticks.

NEWYORKER: Net Impact

That technique uses a magnetic field to hold large volumes of the same isotopes of hydrogen inside a doughnut-shaped vessel, called a tokamak.

ECONOMIST: Nuclear fusion