Internal cleaning work and troubleshooting must be performed by professional personnel.

仪器内部清洁工作及故障修理，必须由专业人员操作。

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The scope covers storage, handling, inspection, testing, load-out (two simultaneous vessel load-out points), internal cleaning and maintenance of flexible pipes.

合同内容包括挠性管的存储、操作、检验、测试、装运、内部清理和维护工作。

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The core method of internal cleaning was taken by improving the diesel design, combined with exhaust's aftertreatment, to study on the diesel particulate control.

本文对控制柴油机微粒的排放进行了深入的研究，采用了以改进柴油机设计为核心的机内净化措施，并与排气后处理措施相结合。

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As those in Oklahoma began the long process of cleaning up after the storm, the Internal Revenue Service announced tax relief to individuals and businesses to those impacted by the tragedy.

FORBES: IRS Announces Tax Relief For Oklahoma Tornado Victims

Its unpublished internal tests have found the brush is six times more effective than cleaning using hands, the company says.

WSJ: Sonic Facial Brushes: Deep Cleaning Faces at the Speed of Sound

It says its members' alternative suggestions for saving money include scrapping the internal market in the NHS and bringing outsourced services such as bin collection and street cleaning back under public control.

BBC: Unions urge different approach as cuts debate continues