function centralize(e) {
		  e.moveTo(
			  ((screen.width/2) - (e.innerWidth ? e.innerWidth : e.document.body.offsetWidth)/2),
		  	((screen.height/2) - (e.innerHeight ? e.innerHeight : e.document.body.offsetHeight)/2)
		  );
	  }
		function abreJanela(url,largura,altura) {
			centralize(window.open(url,"",'toolbar=no, left=400 ,screenX=0, screenY=0, directories=no,status=no,menubar=no,scrollbars=no,resizable=yes,width='+largura+',height='+altura));
		}