These CDs have a dye layer that the CD writer can darken or leave clear. The clear and dark spots are the digital code.

这种光盘有一种染色层，光盘刻录机可以将其涂黑或者留一些空白，这些黑点和空白点就是数码。

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Within the solar cell, the dye is paintedin a thin layer on a porous titanium dioxide scaffold to collect light and, ina series of steps, create power.

在太阳能电池内，染料涂在多孔的二氧化钛支架上来收集光线，然后经过一系列步骤，就产生了电流。

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Suitable for heavy & Bulky fittings, e. g. : Al Dye & Anodize, multi-layer circuit board and barrel plating.

适用于重型配件处理，如铝氧化及电镀，多层线路板制造，大型滚桶电镀等。

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If you want black, or white, or any other colour, then you need to anodise so that you can dye that layer.

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The real reason, I suspect, that this has been done on the iPhone is that it is this anodised layer that you can then dye to pretty much any colour you want.

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The system the researchers tested used a type of solar cell known as dye-sensitized solar cells, a lightweight and inexpensive type where the active layer is composed of titanium dioxide, rather than the silicon used in conventional solar cells.

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