function janelaSecundaria (URL, largura ,altura)
{
    //window.open(URL,"janela1","width=430,height=430, top=400, left=300, status=yes, scrollbars=NO")
var esquerda = (screen.width - largura)/2;
var topo = (screen.height - altura)/2;

window.open(URL,'','height=' + altura + ', width=' + largura + ', top=' + topo + ', left=' + esquerda + ', status=yes');
}