function externalLinks() {
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    return;
  }

  var anchors = document.getElementsByTagName("a");

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    if (anchor.href && anchor.href.substr(0,7) == "http://"
      && anchor.href.substr(0,30) != "http://www.nanotecexpo.com.br/") {
      anchor.target = "_blank";
    }
  }
 }

window.onload = externalLinks;