These coarse, imitation homes were commissioned and owned almost exclusively by the middle classes, as evidence of their prosperity.

这些粗糙的，仿制的房子几乎专为中产阶级所定制，也为他们所拥有，作为他们财富的证明。

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These porous sheets, which together form a coarse white powder, vastly outperformed sheets that did not have the pores, and commercially available chunks of boron nitride that is not made up of the tiny sheets.

BBC: 'White graphene' soaks up pollutants and can be re-used