The results are that, the conventional component and the micro component as well as fluoride, manganese, iron exceed is main reason of bad. quality of groundwater.
To improve the homogeneity of manganese sulfide and calcium fluoride, the machinability could be enhanced.
改善硫化锰和氟化钙的分布，将会改善切削加工性。
3
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.