Few តិចតួច Yet ទោះជាយ៉ាងនេះក្តី MP3 Players ប្រដាប់ចាក់ចម្រៀង Mp3
Denied បដិសេធ rare earth metals លោហធាតុដីកម្រមាន
four billion dollars worth ចំនួន៤ពាន់លានដូល្លារ So
ហេតុដូច្នេះហើយ
mine ជីក Well នែ periodic table of the elements តារាងនៃធាតុ physicist អ្នករូបនិយម properties គុណសម្បត្តិ
magnets មេដែក hybrid vehicles រថយន្តប្រើប្រេងឥន្ធនៈនិងអគ្គីសនី
X-rays កាំរស្មីអិចស៍
Few
people have ever heard of the natural elements known as rare earth metals
before a recent dispute between China and Japan.
Yet these
metals are used in devices like smartphones, flat screen televisions, hybrid
care batteries, MP3 Players and
military equipment. In September, Japan detained a Chinese ship captain near
disputed islands in the East China Sea. China denied
that it stop exports rare earth metals to Japan to force his release. But the
incident raised concerns.
Japan is the world’s biggest importer of rare earth metals. And China produces
ninety-seven percent of the world supply. China says it sold almost four billion dollars’ worth in two thousand eight. But marketing professor George
Halley at the University of New Haven in Connecticut says China has always kept
prices low.
He says: “So
unlikely other minerals the price of rare earth elements has actually fallen.”
Some countries with rare earth metals no long mine them—including the United States. One
reason is the low-cost imports from China. Another reason is concern about
environmental damage. So what are these rare earth metals? Well, most of them are not rare; but is just their
name. Several are most common than copper, lead or silver.
People who remember the periodic
table of the elements from chemistry class might recognize them.
Rare earth includes the fifteen lanthanide metals along with yttrium and
scandium. Samual Bader, a physicist
at the Argonne National Laboratory near Chicago, says rare earths are often
found together. But Mr. Bader explains that the same properties that make them hard to refine also
make them valuable. He says: “Rare earth metals provide the world’s strongest
commercial magnets. This is why
they’re important. It’s that simple.” Rare earth magnets are lightweight and
unaffected by conditions like high temperatures. So they work well in places
like electric motors in hybrid vehicles
or generator for wind turbines.
Physicist used super- powerful magnets to speed particles
and control radiation like X-rays. Goerge Halley says
they are found in electronics, fiber options and other products. They are
important not just for economic success of the United States, but for defense
and job creation at home. Next week, we’ll talk more about rare earth metals,
and an American company that plan to start mining them again.
No comments:
Post a Comment