盖玻片是由经过优良化学阻力和平滑处理的纯白色光学玻璃制作而成的，无气泡和刮痕。

Microscope cover glasses are made of pure white borosilicate glass with excellent chemical resistance and flatness, and are free of bubbles and scratches.

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粘度：原油粘度是指原油在流动时所引起的内部摩擦阻力，原油粘度大小取决于温度、压力、溶解气量及其化学组成。

Viscosity: viscosity is the crude oil in the flow caused by the internal frictional resistance, crude oil viscosity depends on temperature, pressure, dissolved gas and its chemical composition.

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采用化学清洗和空气爆破相结合的方法，清除换热器中由变换气及催化剂粉末等形成的垢物，降低换热器的阻力，提高热效。

Combining the chemical cleaning and air blasting method, this paper introduces a new method of removing the deposit resulting from the shift gas and catalyst powder, etc.

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