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

The current methods for realization of the second with the highest accuracythrough the frequency of the hyperfine transition between two levels of theground state of the cesium 133 atom are considered. It is discussed possibleways for the future redefinition of the SI time unit with the help of opticalfrequency standards, as well as thorium and super-high frequency standards.Several constants which can be also used for definitions of the time, mass andelectric current units are analyzed.

On possible ways for future redefinition of the SI time unit