First produced in a lab back in 2004, graphene is essentially a single layer of pure carbon atoms bonded together in a honeycomb lattice so thin it's actually considered two-dimensional.

石墨烯最早在2004年诞生于一个实验室，本质上是一层由纯碳原子组成的蜂窝状晶格层，薄到竟被认为是二维物质。

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A true epithelial tissue is present only in a single layer of cells held together via occluding junctions called tight junctions.

真正的上皮组织仅存在于通过称为紧密连接的咬合带而保持在一起的单层细胞中。

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These layers are called strata and a single layer is called a stratum.

这些岩层被称作地层（strata）（stratum的复数形式）， 单个岩层称为stratum。

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L is for layers.Wearing loose, lightweight clothes, one layer on top of another, is better than wearing a single heavy layer of clothing.

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s a single cell layer of a damage cochlea.

损伤后的耳蜗只有一层薄薄的细胞膜，There’

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Nine hundred million of these zinc oxide crystals could be spread across the head of a pin in a single layer.

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Like the panel on the RT, it's optically bonded, meaning the LCD and touch panel comprise a single layer.

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Some 900 million of these zinc oxide crystals can fit in a single layer on the head of a pin.

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