function janelaSecundaria (URL,largura,altura)
	{
	xtop=((screen.height-altura)-((screen.height-altura)%2))/2;
	yleft=((screen.width-largura)-((screen.width-largura)%2))/2;
config="width="+largura+",height="+altura+",top="+xtop+",left="+yleft+", scrollbars=yes, status=NO, titlebar=NO";
	 window.open(URL,"janela1",config)
	}