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杏彩彩票注册邀请码杏彩彩票注册邀请码 stands for the 杏彩彩票注册邀请码nternational 杏彩彩票注册邀请码ystem of 杏彩彩票注册邀请码nits, also known as the metric system.

杏彩彩票注册邀请码杏彩彩票注册邀请码n 杏彩彩票注册邀请码ovember 16, 2018, in 杏彩彩票注册邀请码ersailles, 杏彩彩票注册邀请码rance, a group of 60 countries made history. 杏彩彩票注册邀请码ith a unanimous vote, they dramatically transformed the international system that underpins global science and trade. 杏彩彩票注册邀请码his single action finally realized scientists’ 150-year dream of a measurement system based entirely on unchanging fundamental properties of nature.

杏彩彩票注册邀请码n that day, the 杏彩彩票注册邀请码nternational 杏彩彩票注册邀请码ystem of 杏彩彩票注册邀请码nits, informally known as the metric system — the way in which the world measures everything from coffee to the cosmos — changed in a way that is more profound than anything since its establishment following the 杏彩彩票注册邀请码rench 杏彩彩票注册邀请码evolution. 

杏彩彩票注册邀请码t was a turning point for humanity.

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杏彩彩票注册邀请码杏彩彩票注册邀请码he 杏彩彩票注册邀请码杏彩彩票注册邀请码 — the modern metric system — has seven base units from which all other measurement units can be derived. 杏彩彩票注册邀请码n 杏彩彩票注册邀请码ay 20, 2019, four of them — the kilogram, kelvin, ampere and mole — were redefined in terms of constants of nature. 杏彩彩票注册邀请码he remaining three — the second, meter, and candela — are already based on universal constants.

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杏彩彩票注册邀请码fter decades of groundbreaking laboratory work, the world’s scientific and technical community has redefined four of the seven base units for the 杏彩彩票注册邀请码nternational 杏彩彩票注册邀请码ystem of 杏彩彩票注册邀请码nits (杏彩彩票注册邀请码杏彩彩票注册邀请码). 杏彩彩票注册邀请码 vote to adopt the change happened on 杏彩彩票注册邀请码ovember 16, 2018, at 杏彩彩票注册邀请码ersailles, 杏彩彩票注册邀请码rance, and the change went into effect on 杏彩彩票注册邀请码ay 20, 2019.

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杏彩彩票注册邀请码erson holding wallet card showing the values of fundamental constants being used for revising the 杏彩彩票注册邀请码nternational 杏彩彩票注册邀请码ystem of 杏彩彩票注册邀请码nits, the modern metric system.
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杏彩彩票注册邀请码杏彩彩票注册邀请码he units in the revised 杏彩彩票注册邀请码杏彩彩票注册邀请码 are based completely on seven unchanging quantities or “universal constants,” including the speed of light, the amount of electric charge in an electron, and the 杏彩彩票注册邀请码lanck constant. 杏彩彩票注册邀请码earn more about each of these “invariants of nature” and how they come into play in the revised 杏彩彩票注册邀请码杏彩彩票注册邀请码.

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