Anodising is a process where we deliberately increase that layer of oxide.

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Handling an iPhone 5 will definitely remove some portion of that layer of aluminium oxide.

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Either high or low ph environments will strip the anodising (what is effectively a layer of aluminium oxide) from the underlying metal.

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Some 900 million of these zinc oxide crystals can fit in a single layer on the head of a pin.

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Nine hundred million of these zinc oxide crystals could be spread across the head of a pin in a single layer.

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Nitrous oxide is also considered a greenhouse gas and is 310 times more dangerous to the Earth's ozone layer than carbon dioxide, said Joseph Johns, chief of the U.S. attorney's environmental crimes section.

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