Inorganic mineral elements in tea are about 27 species, including phosphorus, potassium, sulfur, magnesium, manganese, fluoride, aluminum, calcium, sodium, iron, copper, zinc, selenium and other.

茶叶中的无机矿质元素约有27种，包括磷、钾、硫、镁、锰、氟、铝、钙、钠、铁、铜、锌、硒等多种。

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Control technology on indoor pollution of coal combustion in rural area, especially the progress in technique of coal fluoride-sulfur fixing was introduced in this paper.

介绍了针对农村室内燃煤污染的清洁技术，特别是固氟固硫技术研究的进展。

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