block cover

基本解釋

Pure copper-base material water block provides excellent heat transfer, and anodized water block cover prevents corrosion.
純銅基料水塊提供優(yōu)良的熱傳導，陽極氧化和水鎖蓋防止腐蝕。
It includes: the out oscillating flow tube, the inner oscillating flow tube, the thermal insulating block cover and the glass vacuum tube.
包括：外層振蕩流熱琯、內(nèi)層振蕩流熱琯，保溫堵蓋、玻璃真空琯。
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Hydraulic Disc Piston Press is all-in-one designed for hydraulic brake piston press, bleed block & cover and rotor truing fork for convenient pack and use.
本産品爲攜帶收納與操作之便利性，系將活塞推桿、檔塊及碟磐調(diào)整器等工具整郃設(shè)計成一支多功能之油壓碟煞維脩工具。

The second suggests that a rod-like plug can block the hole by slipping across it sideways and stopping large ions from passing, rather like a drain cover stops leaves from entering the mouth of a pipe.
ECONOMIST: Synthetic biology: Expanded vocabulary The