procedure TForm2.Notebook1PageChanged(Sender: TObject);
begin try
menu_update1.Enabled :=true;
form1.a_page.tag:=NoteBook1.PageIndex;
AddThisArticletotheResearchProject1.Enabled :=(Notebook1.PageIndex <> 1)and(Notebook1.PageIndex <> 4)and(Notebook1.PageIndex <> 10);
AddAllImagestotheResearchProject1.Enabled := AddThisArticletotheResearchProject1.Enabled;
except end;End;