The optimal weight fraction is 0.1%, for under this condition, the wear scar diameter is decreased 35.6% and lubricating oil has great time-release effect.

当铜镍复合粉体的质量分数达到0.1%时，磨斑直径降低幅度最大，达35.6%，并具有很好的长效减摩性能。

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That might not seem like much, but considering most rigid robot arms can only lift a fraction of their own weight, it represents a sizable gain in strength-to-weight ratio.

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The NX20 is the perfect match for enthusiast amateur or professional photographers looking for a highly portable camera that gives the professional look and feel of a DSLR but at a fraction of the size and weight, with the addition of an ergonomic grip to fit comfortably into the hand.

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