通过煤质特征、 矿物学和元素的组相关性分析，概括了引起这两种类型煤常量和微量元素之间差弄的地质原因。

Through analyses of relativity on coal quality and mineralogy and elements, summarized geological reasons caused differences between norm al and trace elements in the two types of coal.

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矿泉水不仅含有人体必需的常量元素，而且含有各种对人体有益的矿物质和微量元素。

Mineral water contains not only common elements necessary to human body, but also all kinds of minerals and trace elements which are good for human health.

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本文报道1986～1987年对252例正常妊娠孕妇及其新生儿进行了头发和血清9种微量元素和常量元素的测定。

Between December 1986 and December 1987, the determinations of nine kinds: of trace and common elements in hair and serum of 252 normal pregnant women and their infants are reported.

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