然后可以将氢气输入到存储系统中，并在需要附加或备用电源时用于发电。

The hydrogen gas could then be fed into a storage system and used to generate electricity when additional or backup power is needed.

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在她的费用申请被驳回后，她从小额备用金中取了钱。

After having her expense claims overruled, she took the money from petty cash.

《柯林斯英汉双解大词典》

在备用配置中，备用服务器在等待生产服务器发生故障时是空闲的。

In a standby configuration, the standby server will be idle while it waits for the production server to fail.

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