By comparison the density of silica aerogels - the world's lightest solid materials - is only as low as 1.0mg per cubic cm.

相比之下，世界上最轻的固体材料——硅土气凝胶的密度最小也要每立方厘米1.0毫克。

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The dimension of the cases are 17cm high, 30 cm wide and 50 cm long with a volume of about 0.026 cubic meter. The gross weight is 23.5kg.

纸盒的尺寸为高17 cm，宽30 cm，长50 cm，体积为0.026 m3，毛重为23.5 kg。

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