Aqueous Extract of Kalmegh (<i>Andrographis paniculata</i>) Leaves as Green Inhibitor for Mild Steel in Hydrochloric Acid Solution

<table class="table-group" id="tab5"><tr><td><table class="table"><tr><td class="thead-hr" colspan="2"><hr/></td></tr><tr class="thead"><td align="left">Frequency (<svg height="16.049999" id="M156" style="vertical-align:-0.16379pt" version="1.1" viewbox="0 0 34.549999 16.049999" width="34.549999" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink">
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t-52 18.5v23q79 14 139 41v-81q3 2 29 20.5t44 29.5q45 28 81 28t66 -22t46 -61q25 20 83 57q39 26 76 26q59 0 93 -40t34 -113v-193q0 -49 10.5 -60.5t54.5 -16.5v-26z" id="x6D"></path></g>
<g transform="matrix(.012,-0,0,-.012,21.175,7.613)"><path d="M535 230h-483v50h483v-50z" id="x2212"></path></g><g transform="matrix(.012,-0,0,-.012,28.16,7.613)"><path d="M384 0h-275v27q67 5 81.5 18.5t14.5 68.5v385q0 38 -7.5 47.5t-40.5 10.5l-48 2v24q85 15 178 52v-521q0 -55 14.5 -68.5t82.5 -18.5v-27z" id="x31"></path></g>
</svg>)</td><td align="center">     Band assignment</td></tr><tr><td class="thead-hr" colspan="2"><hr/></td></tr><tr><td align="left">1080</td><td align="center"> C–O stretching</td></tr><tr><td align="left">1226</td><td align="center"> C–O stretching</td></tr><tr><td align="left">1373</td><td align="center">  C–H bending (methyl)</td></tr><tr><td align="left">1725</td><td align="center"> C=O stretching</td></tr><tr><td align="left">2880</td><td align="center"> C–H stretching</td></tr><tr><td align="left">3268</td><td align="center"> O–H stretching</td></tr><tr class="table-tr"><td colspan="2"><hr class="tbody-hr"/></td></tr></table></td></tr></table>

Prominent peaks obtained from reflectance FTIR spectroscopy.

International Journal of Corrosion

tab5

Table 5

Table 5: Aqueous Extract of Kalmegh (<i>Andrographis paniculata</i>) Leaves as Green Inhibitor for Mild Steel in Hydrochloric Acid Solution 

International Journal of Corrosion

Aqueous Extract of Kalmegh (Andrographis paniculata) Leaves as Green Inhibitor for Mild Steel in Hydrochloric Acid Solution

Table 5