According to the shell material can be divided into economic and luxury.

根据外壳材料又可分为经济适用型和豪华型。

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The higher impurity composition of tower shell material was the main reason occurring the crack of this type.

而塔体材料中较高的杂质成分，是引起这种开裂的最主要原因。

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The shell material used in diversity: Aluminum Alloy, color steel plate, stainless steel plate, galvanized plate etc.

外壳所用材质多样：铝合金、彩钢板、不锈钢板、镀铝锌板等。

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Each shell contains a small amount of explosive material, and some is used to produce whistles and other effects.

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In order to clone a human, scientists would remove the nucleus of an egg and extract its genetic material, leaving just its shell.

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In this research the scientists created a synthetic viral shell, but lacking its pathogenic RNA interior - the genetic material the virus uses to replicate itself.

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