metals

Most forms of steel abruptly become brittle at temperatures below about -25°C unless they are mixed with other metals.

Rather than adding other metals, they developed a complex mechanical process involving repeated heating and very severe mechanical deformation, known as temp-forming.

So scientists have strived to find a solution by mixing it with expensive metals such as nickel.

This is partly driven by the rising price of raw materials and metals.

Together, the value of these metals is estimated to be about $52 billion.

A Swiss study reported that while the weight of electronic goods represented by precious metals was relatively small in comParison to total waste, the concentration of gold and other precious metals was higher in so-called e-waste than in nature.

Consider again the cell-phone, and imagine the mines that produced those metals, the factories needed to make the box and packaging (包装) It came in.

Electronic devices contain valuable metals such as gold and silver.

Electronic wastes also contain many poisonous metals.

Even when the machines are recycled and the harmful metals removed, the recycling process often is carried out in poor countries, in practically uncontrolled ways which allow many poisonous substances to escape into the environment.

Natural minerals contain more precious metals.

The percentage of precious metals is heavy in e-waste.