></a><span class="lineno">   16</span>&#160;                                              <span class="stringliteral">&#39;SF4&#39;</span>,  <span class="comment"># iron/sulfur cluster</span></div><div class="line"><a name="l00017"></a><span class="lineno">   17</span>&#160;                                              <span class="stringliteral">&#39;EOH&#39;</span>,  <span class="comment"># ethanol</span></div><div class="line"><a name="l00018"></a><span class="lineno">   18</span>&#160;                  