The pelitic mineralogy of the magnetite gneiss and presence of detrital zircon demonstrate that the protoliths were not a pure chemical sediment.

磁铁矿片麻岩的泥质矿物特征和碎屑锆石的存在表明，原岩不是一个纯化学沉积体。

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The result of the laboratory analysis of the lacustrine chemical sediment samples from Dongdagou in the Datong Basin shows that the chemical matter is a hydromagnesite.

大同盆地东大沟湖成化学沉积物样品的实验室分析结果表明，该化学物质是水菱镁矿。

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The advantages and disadvantages of the catalysts prepared by rapid quenching method, chemical sediment method, and chemical reduction impregnation method were discussed.

阐述了淬冷法、 化学沉积法、 化学还原浸渍法制备的非晶态合金催化剂的优缺点。

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In any case, the world-class agriculture in the delta employs advanced seed technology and chemical fertilisers, and does not depend on river-borne sediment of negligible nutrient value.

ECONOMIST: Letters