English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Tools annual

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools monthly

Global: Zendy Plus monthly

Presents the access of premium content as premium feature

Premium Content

Global: Zendy Plus annual

Global: Zendy Free Plan

Single pressure refractive index gas thermometry (SPRIGT) is a novel primarythermometry, jointly developed by TIPC of CAS in China and LNE-Cnam in France.To realize a competitive uncertainty of 0.25 mK for thermodynamic temperaturemeasurements, high-stability and low-uncertainty of microwave resonancefrequency measurements better than 2 ppb should be achieved. This articledescribes how to realize high-stability and low-uncertainty of resonancefrequency measurements in a copper microwave cavity by experimentaloptimization methods based on Allan analysis of variance. In this manner, 10-12level accuracy and stability of microwave resonance frequency measurements wererealized with an integration time of 3 hours, which is nearly 20 times betterthan those without optimization in our previous work (Sci. Bull 2019; 64:286-288). It has potential applications in gas metrology and other researchfields, where high-stability and low-uncertainty microwave measurements arenecessary. Besides, microwave measurements were carried out isobarically atpressures of (30, 60, 90, and 120) kPa over the temperature range of (5 to 26)K, with good microwave mode consistency for the determined thermodynamictemperatures. These will provide strong support for the success of theimplementation of SPRIGT in China.

Resonance frequency measurement with accuracy and stability at the 10-12 level in a copper microwave cavity below 26 K by experimental optimization