if(document.getElementById('relative'))document.getElementById('relative').innerHTML='<div>前一篇：<a href=\"/other/chem_knowledge/show.asp?id=194001\" target=\"_self\">信用证的种类</a></div>\n<div>后一篇：<a href=\"/other/chem_knowledge/show.asp?id=194039\" target=\"_self\">氯甲烷简要介绍</a></div>\n';