The black material is considered as carbon deposition, which is formed by oily-liquid medium fission product (mainly carbon black) covering inside crack during the discharge process of pulse current.

认为这些黑色覆盖物为脉冲电流在放电过程中，油性液体介质裂变产物(主要为碳黑)涂覆在裂纹内部形成的积碳。

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This article describes drainage design principle for planted roof, and puts forward that increasing drainage gradient of both roof and growing medium layer could speed up water discharge.

叙述了种植屋面的排水设计原则，提出可通过加大屋面排水坡度和种植介质表面排水坡度等措施，达到快速排放屋面积水的目的。

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The connecting wire used for the PD test of HV cables was improved based on the corona discharge theory in air medium.

利用空气介质中电晕放电理论对高压电缆局部放电试验连接导线进行了改进。

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