The Inhibited Effect of Cysteine Towards the Corrosion of Copper in Nitric Acid Solution
The detailed study of cysteine (Cys) as corrosion inhibitor for copper in nitric acid solution has been performed through weight loss, electrochemical polarization, electrochemical impedance spectroscopy (EIS) and scanning electron microscopy (SEM) measurements. The effect of inhibitor concentration, temperature and immersion time against inhibitor action was investigated. Results show that Cys may be used as an efficient inhibitor for copper in nitric acid at higher temperatures (98% at 50°C). Potentiodynamic polarization studies reveal that Cysteine acts as a mixed-type inhibitor without any change in the mechanism of hydrogen evolution. The adsorption of this compound on copper surface obeys Langmuir's adsorption isotherm and has a chemisorptions mechanism.
The inhibition of mild steel corrosion in acidic solutions by 2,5-bis(4-pyridyl)-1,3,4 -thiadiazole : Structure-activity correlation
Abstract The effect of 2,5-bis(4-pyridyl)-1,3,4-thiadiazole (4-PTH) on the corrosion of mild steel in acidic media (1 M HCl, 0.5 M H 2 SO 4 , 1 M HClO 4 ) has been investigated using weight loss measurements, electrochemical impedance spectroscopy and potentiodynamic polarisation. These studies have shown that 2,5-bis(4-pyridyl)-1,3,4-thiadiazole is good inhibitor for mild steel in 1 M HCl, 0.5 M H 2 SO 4 and 1 M HClO 4 solutions, the better performances are seen in the case of 1 M HCl solutions. But in 1 M HClO 4 , the 4-PTH stimulates corrosion at low concentrations. Polarisation curves indicate that the 4-PTH is a mixed-type inhibitor in all acidic media and E (%) is temperature-dependent. Adsorption on the mild steel surface follows the Langmuir isotherm model in all acidic media. The electronic properties obtained using the Hartree–Fock AB initio 3-21G quantum chemical approach, were correlated with the experimental efficiencies.
Evaluation of Impact of Yarn Count and Stitch Length on Pilling, Abrasion, Shrinkage and Tightness Factor of 1 ? 1 Rib Cotton Knitted Fabrics
This study investigates the impact of yarn count and stitch length of 100% cotton knitted fabrics. 1 × 1 ribs structured fabrics were used in this research work. The stitch length 2.50 mm, 2.52 mm, 2.60 mm, 2.70 mm, 2.80 mm and 2.96 mm were used of the yarn count of 26Ne, 28Ne and 36Ne. The areal densities of the grey fabrics were in various amounts. The impacts of yarn count and stitch length were measured concerning pilling resistance, abrasion resistance, and shrinkage and tightness factor. The result showed that the fabric pilling grade decreased while number of cycle increased. Abrasion resistance decreased but length wise shrinkage increased despite the fact that the stitch length increased. The results also exposed that the tightness factor of the fabric increased with the increase of the stitch length in both dyeing and washing state and finished state compared to grey state for the yarn count 26Ne and homogeneous result not found for yarn count 28Ne and 36 Ne. Evaluation of Impact of Yarn Count and Stitch Length on Pilling, Abrasion, Shrinkage and Tightness Factor of 1 × 1 Rib Cotton Knitted Fabrics