The article brings a discussion to the technology of melting high impurity black copper with a tilting furnace. It is a good attempt of new adopted smelting technology.

对倾动炉处理高杂质黑铜的冶炼技术进行了多方面的论述，对新的冶炼操作方式进行有益的尝试。

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In several reactions a colour change indicates the formation of new products. For example, green copper carbonate reacts, when heated, to form black copper oxide and carbon dioxide gas.

在一些反应中颜色会发生变化，它表明产生了新的物质，例如，绿色的碳酸铜在加热时会分解为黑色的氧化铜和二氧化碳气体。

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Depending on individual habitats, which extend from the tropical forests of Costa Rica to Brazil, their coloring can be yellow, gold, copper, red, green, blue, or black.

它们遍布于哥斯达黎加、巴西等热带雨林中，其肤色通常为黄色、金色、铜色、红色、绿色、蓝色或黑色。

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You see, the day you start selling black market copper wire to pay for Diet Coke is the day you realize you have a serious problem.

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Smearing a small copper plate with black ink, Francesca rubbed the excess away, carefully pushing it into the etched grooves.

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She was dressed in stylish business clothes black patent-leather high heels, a knee-length, copper-colored dress, and a short-waisted black jacket and looked more like a media executive than a food-industry chieftain.

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