These desulfurizing agents proved to be excellent: reducing the total sulfur of LPG significantly and making the grade of copper stain test go down from 3 to 1.

结果表明，该脱硫剂脱硫效果很好，使液化气的铜片腐蚀从3级降至1级，总硫明显下降。

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Laser beams could be sent down fiber-optic cable to power anything currently powered by copper wire.

镭射光也可以通过地下光缆来传输能量，来代替铜线传输。

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This should all be bullish for commodities, such as copper, oil and gold, and also trickle down to boost share prices of natural resources equities.

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