Articles - Title in navigator

[gnrx]

Hi.
I view that, when I acces to article in my forum, in title of navigator appears:
Articles - Mozilla Firefox (I use firefox, xDD).
In others sections or in others sites, I view appears: Articles - Name of site.
How can change this value for appears "Articles - Name of site" in navigator title?
I search in phrases but I don't view the phrase for this.

Thanks and regards.