Abstract The inhibition effect of Thymus zygis subsp. gracilis (TZ) on mild steel corrosion in 1 m hydrochloric acid has been investigated by weight loss measurements, surface analysis [scanning electron microscopy (SEM)-energy-dispersive X-ray (EDX), three-dimensional (3D) profilometry, and Fourier transform infrared analysis], potentiodynamic polarization, and electrochemical impedance spectroscopy (EIS). Gravimetric results indicate that TZ exhibits good inhibition efficiency of 80.40% attained at 3 g/l. Polarization measurements show that the studied inhibitor is a mixed type. EIS measurements revealed that the charge transfer resistance increases with increasing concentration of TZ, which suggests a Langmuir adsorption isotherm model. Based on SEM-EDX and 3D profilometry, it appears that the surface is remarkably improved in the presence of TZ oil compared to that exposed to the acid medium without TZ oil. From the obtained results, it can be concluded that this oil is a new natural substance that can be used against material corrosion in aggressive medium.

中文翻译：

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Thymus zygis subsp. 缓蚀和吸附行为的评价。在 1 m HCl 中低碳钢表面的 gracilis 挥发性化合物

摘要 Thymus zygis subsp. 的抑制作用。已通过重量损失测量、表面分析 [扫描电子显微镜 (SEM)-能量色散 X 射线 (EDX)、三维 (3D) 轮廓测定法和傅里叶变换红外分析]、动电位极化和电化学阻抗谱 (EIS)。重量分析结果表明，TZ 在 3 克/升时表现出良好的抑制效率，达到 80.40%。极化测量表明所研究的抑制剂是一种混合型。EIS 测量显示电荷转移电阻随着 TZ 浓度的增加而增加，这表明朗缪尔吸附等温线模型。基于 SEM-EDX 和 3D 轮廓测量，与暴露在不含 TZ 油的酸性介质中的表面相比，在存在 TZ 油的情况下，表面似乎得到了显着改善。从获得的结果可以得出结论，这种油是一种新的天然物质，可用于抵抗腐蚀性介质中的材料腐蚀。