function open_win(janela, win_w, win_h, url, scrollbar, resizable, status)
{
	var w = screen.width;
	var h = screen.height;
	w = w - win_w;
	h = h - win_h;
	w = w/2;
	h = h/2;
	zoom = window.open(url, janela, 'width='+win_w+', height='+win_h+', toolbar=no,copyhistory=no,location=no,status='+status+',menubar=no,scrollbars='+scrollbar+',resizable='+resizable+',top='+h+',left='+w+'');
	zoom.focus();
}