The periodic table seems to epitomize an older, well-established version of science that is more high school chemistry than high-tech wind turbines or fuel-efficient car engines.

But whole swaths of the periodic table that most people have never heard of are crucial for technology and clean energy generation. And in recent years, these materials, with names like neodymium and yttrium, have been threatened by shortages and international politics.

Last year, the Department of Energy funded a $120 million Critical Materials Institute at the Ames Laboratory in Iowa, devoted to increasing production and developing substitutes that could prevent shortages.

At Northeastern University, chemical engineer Laura Lewis sums up the scientific problem she is working on with a quick demonstration: she’ll push a shallow metal dish with a slightly rusted magnet in it across a table and challenge visitors to try and pry the magnet off. It’s possible — but very difficult.