VOA慢速英语2014 Remember Your Chemistry Classes?

（单词翻译）

As It Is - Remember Your Chemistry Classes?

An international team of researchers recently reported creation of a new element that is 40 percent heavier than lead.

The researchers successfully developed what they are calling Element Number 117 at a laboratory in Germany. It is identified by that number because its nucleus¹ contains that same number of particles --called protons. Element Number 117 has a temporary name -- ununseptium.

If you remember your chemistry classes in school, you will recall that about 90 elements in the Periodic Table are found in nature. But others that were created in laboratories appear only in very small amounts.

The Periodic Table lines up -- or organizes -- chemical elements in order of atomic number. The elements made in laboratories -- such as 117 -- are extremely unstable². They last only minutes before breaking down into long-lasting elements.

Creation of new elements helps scientists better-understand the chemistry and physics of atoms. But such production may also lead to the discovery of new technologies.

Russian and other scientists had reported the creation of Element 117 in 2010. But the group that confirms new elements requires at least two successful independent experiments to confirm their existence. That group -- the International Union of Pure and Applied³ Chemistry -- will give the element a permanent name.

A report on the new element appears in the journal Physical Review Letters.