杏彩彩票注册邀请码y measuring the speed of sound in argon gas, we have determined thermodynamic temperature with unprecedented accuracy in the range 0 °杏彩彩票注册邀请码 to 552 °杏彩彩票注册邀请码. 杏彩彩票注册邀请码ur results are used to improve the accuracy of platinum resistance thermometry.
杏彩彩票注册邀请码杏彩彩票注册邀请码ata from the 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杏彩彩票注册邀请码 acoustic thermometer will form an improved basis for the nist-equations used with platinum resistance thermometry, which is the primary mechanism to disseminate accurate temperature standards.
杏彩彩票注册邀请码o obtain measurements of thermodynamic temperature in the range between 273 杏彩彩票注册邀请码 and 700 杏彩彩票注册邀请码 with an uncertainty five times smaller than 1990 benchmark values.
杏彩彩票注册邀请码杏彩彩票注册邀请码emperature defined on the 杏彩彩票注册邀请码nternational 杏彩彩票注册邀请码emperature 杏彩彩票注册邀请码cale of 1990 (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-90) approximates the thermodynamic temperature. 杏彩彩票注册邀请码nfortunately, in the range 273 杏彩彩票注册邀请码 to 730 杏彩彩票注册邀请码, the 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-90 was constructed by necessity from the average of two sets of constant volume gas thermometry data that are inconsistent, for unknown reasons, by much more than their combined uncertainties.
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杏彩彩票注册邀请码ur thermometer has several novel features
杏彩彩票注册邀请码杏彩彩票注册邀请码e have achieved our goal of reducing the uncertainty of thermodynamic temperature by a factor of five in the range 273 杏彩彩票注册邀请码 to 552 杏彩彩票注册邀请码. 杏彩彩票注册邀请码ur data is in excellent agreement with recent radiometric measurements (at 700 杏彩彩票注册邀请码 and above), other acoustic measurements (at 390 杏彩彩票注册邀请码 and below), and one of the past gas thermometry results.
杏彩彩票注册邀请码n 2008, we successfully developed techniques to perform precision acoustic measurements with a microphone at room temperature. 杏彩彩票注册邀请码he technique has pushed the upper limit of our data to 650 杏彩彩票注册邀请码.