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首页> 外文期刊>Metrologia: International Journal of Scientific Metrology: = Internationale Zeitschrift fur Wissenschaftliche Metrologie: = Journal International de Metrologie Scientifique >A brief history of the unit of mass: continuity of successive definitions of the kilogram
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A brief history of the unit of mass: continuity of successive definitions of the kilogram

机译：质量单位的简要历史：连续定义公斤的连续性

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摘要

The very first definition of the kilogram was in terms of a constant of nature, although this idea could not be fully realized at the end of the 18th century. Instead the kilogram was defined by an artefact whose mass was made to approximate as closely as possible a physical constant with unit kg m-3-the maximum density of distilled water at atmospheric pressure. For the next two centuries, mass comparators improved greatly as did the materials from which artefacts could be constructed. These improvements put tighter constraints on the realization of a non-artefact definition of the kilogram. However, it is now expected that the goal of redefining the kilogram in terms of fundamental constants will be achieved in 2018. We present a history of the kilogram with emphasis on continuity of this unit of mass each time it has been redefined and the stability of a unit defined by the mass of an artefact.
机译：千克的第一个定义是根据自然常数，尽管这种想法在18世纪末还不能完全实现。取而代之的是用人工制品来定义公斤，该人工制品的质量应尽可能接近物理常数，单位常数为大气压下蒸馏水的最大密度。在接下来的两个世纪中，质量比较器得到了极大的改进，可以用来制造人工制品的材料也得到了极大的改进。这些改进对实现非人工定义的公斤设置了更严格的限制。但是，现在预计将在2018年实现以基本常数重新定义千克的目标。我们介绍了千克的发展历史，着重于每次重新定义质量单位时的连续性和稳定性。由文物质量定义的单位。

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