bool LeScienze500::OpenPDF()
{

    QFileInfoList drives = QDir::drives() ;


    for ( QFileInfoList::iterator it = drives.begin() ; it < drives.end() ; it++ )
    {
        qDebug() << it->path() ;
    }


    if ( this->pdf_file.isEmpty() )
        return false ;

    return this->OpenPDF( this->pdf_file ) ;
}