In this paper, the principle of HCBK flame -proof telephone with program control and common-battery telephone public-address is introduced.

本文介绍了集程控和共电式扩音功能于一身的HCBK系列程控防爆扩音对讲电话机的工作原理。

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Explosion-proof flexible connecting pipes is used in explosion-proof telephone station, explosion-proof terminal, explosion-proof loud-speaker inlet or outlet to conduit and protect the cable.

防爆挠线连接管用于防爆电话站、防爆接线箱、防爆扬声器的输入，输出口到布线钢管之间的过渡连接，起到保护电缆的作用。

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The cocoa-tin telephone system is another proof of the way in which solids transmit sounds.

用可可罐头盒做的电话装置是固体传导声音这一方式的另一个证明。

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"We haven't had any proof of life, we haven't had any usage of his bank cards or his telephone so we are fearing the worst, but hoping for the best, " he said on Thursday.

BBC: Missing soldier: Search for Josh Thomas focuses on river

While common sense says that those who spend work hours popping out to the store for a new pair of shoes or surfing the Web for personal use probably cost employers something in lost productivity, there's no definitive proof that employee "downtime" is any more prevalent than it was a generation ago, when telephone and watercooler banter was in.

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