如果早期的海洋内含有有机分子，而这也是非常可能的，海岸线上矿物质的疏松表面可以帮助这些有机分子有机构建成原始的结构。
If early oceans carried organic molecules-and they most likely did-the porous surfaces of shoreline minerals could have helped organize such building blocks into primitive structures.
在显微镜之下，原本看起来很干净的表面其实像砖墙一样凹凸不平，如果这堵墙看起来破烂不堪或疏松易碎，就说明珍珠层没有用。
Under the microscope, the stuff they're after looks like a clean, structurally sound brick wall. If the wall looks ratty or crumbly, it's no good.
铝合金锻件中有时有未锻合的疏松和残留的枝晶自由表面，并保留有原始的结晶台阶。
Unhealed porosities and free surface of dendrites with crystalline steps were occasionally observed in aluminium alloy forgings.
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