в течение длительного времени

I

The transform boundary will not remain for long in its original location.

The pressure increase acts over a long period (of time).

II

There is no prospect of exhaustion of this metal for a long time to come.

An open vessel filled with a superfluid will not stay filled for long.

The neutrino was long thought to be mass-less.

Источник: Русско-английский научно-технический словарь на Gufo.me