Viscous friction is the fiction, or resistance to relative motion, between adjacent layers of liquid. The resistance of motion between these oil layers is called viscous friction.

粘性是液体流层问相对运动而产生的摩擦力或阻力。油层间所产生的运动阻力称为粘性摩擦力。

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Can start the flow of contacts and dynamic friction resistance is to minimize the friction resistance, it can save energy, easy to get a higher velocity.

由于流动接触可使起动磨擦阻力及动磨擦阻力为极小，因此可以节省能源，容易得到较高运动速度。

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With graphite particle content increasing from 5% to 20%, wear weight-loss and friction coefficient of the composites are obviously declined, greatly improving wear resistance of the composites.

随着石墨颗粒含量从5%增加到20%，镁合金基复合材料的耐磨性得到明显的改善，磨损质量损失与摩擦系数都降低到较低水平。

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But while this works in Latvia, a relatively marketised economy, in Greece there is a lot of friction - and not just because of organised labour resistance.

BBC: Greece: How do you save an economy from going bust?