class="lineno">   21</span>&#160;                                            unit=<span class="stringliteral">&quot;angstrom&quot;</span>))</div><div class="line"><a name="l00022"></a><span class="lineno">   22</span>&#160;node.addInput(<span class="stringliteral">&quot;ion_conc&quot;</span>, BSS.Gateway.Float(help=<span class="stringliteral">&quot;The ionic concentration in mol/litre.&quot;</span>,</div><div class="line"><a name="l00023"></a><span class="lineno">   23</span>&#160;                          