Insulating layer: coating on the electrode or hanging fixture, a part of the surface of the part of conductive material layer.

绝缘层：涂于电极或挂具的某一部分，使该部位表面不导电的材料层。

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Following that tradition, the brainiacs over at the University of Reading have developed a new nano-material electrode coating based on the cellular structure of plants.

ENGADGET: Nature-inspired nano-material builds a better electrode, points to greener future (video)