A major sector of ultrafine powders, the superconductor industry alone is expected to reach a volume of $ 225 billion/year by 2020.是什么意思_A major sector of ultrafine powders, the superconductor industry alone is expected to reach a volume of $ 225 billion/year by 2020.在線(xiàn)翻譯_英語(yǔ)_讀音_用法_例句