Tác giả: J. Lenihan

Of the 90 chemical elements that occur in nature, only a dozen are found in easily measurable amounts in the human body. The rest are trace elements, present at such low concentrations that most of …

Of the 90 chemical elements that occur in nature, only a dozen are found in easily measurable amounts in the human body. The rest are trace elements, present at such low concentrations that most of …