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The influence of calcium nitrite corrosion inhibitor on the durability of Portland cement mortars against sulphate solutions was investigated experimentally in the present research. For this reason, mortar specimens were produced using CEM I 42.5N cement and were immersed in different sulphate and sulphate‐chloride contaminated solutions. Sulphate resistance was evaluated according to the procedure described in ASTM C1012. The properties measured were the specimens' expansion, development of compressive strength, changes in corrosion potential and corrosion current density measurements of steel‐containing specimens.

The purpose of this paper was to find a simple and easy-operated method for filtering eco-friendly corrosion inhibitors.

The molecular structures and atomic electronegativities of the four kinds of natural reagents, iota-Carrageenan, sodium alginate, sodium dodecanesulphonate (SDS) and sodium dodecylbenzene sulfonate were calculated by Gaussian and Natural Bond Orbital, and the corrosion inhibition rates were forecasted by the calculated results. Then, the realistic corrosion inhibition efficiency were confirmed by electrochemical impedance spectroscopy and potentiodynamic polarization tests in 3.5 Wt.% sodium chloride corrosive solutions. At the same time, the function of pefloxacin mesylate (PM) was explored in this paper polarization tests in 3.5 Wt.% sodium chloride corrosive solutions.

Results showed that the order calculated by the chemical software was correct, and the corrosion inhibition of SDS was the best. Optimum addition of PM not only can reduce microbial corrosion but also can improve the corrosion inhibition by spatial cooperation.

This method can be used to filter eco-friendly corrosion inhibitors quickly. PM can be also used to improve the corrosion inhibition rate of corrosion inhibitors.

The present method to filter corrosion inhibitors was time-consuming, which needed lots of experiments to verify the corrosion inhibitive efficiency. The calculated method was simpler than others, which need complicated calculation process.

In a critical range of concentrations of chloride ions in sodium hydroxide solutions, mild steel can be anodically polarised, but the polarised state cannot be maintained. It is, however, found that the polarised state can be restored by cutting off the current for a minimum amount of time or by substituting a purely inhibitive solution for the original corrosive solution. The anodic potential accelerates the depassivation caused by chloride ions. It has been observed that cathodic polarisation is only as effective as interruption of the anodic current in restoring the polarised state. The results are discussed in relation to the occurrence of depassivation at a few random spots, and the significance of the results is pointed out from the point of view of the technique for finding out the corrosive or inhibitive character of an environment.

The performance of commercial aluminium as a sacrificial anode for cathodic protection of mild steel in 0.3% sodium chloride has been studied in alkaline compositions for anolyte based on slaked lime. The influence of several addition agents has been investigated with a view to suppressing local cell action in the above‐mentioned environment.

Humidity has a direct effect on the rate of corrosion of metals, complicated by the presence of chloride ion and the nature of the chloride salt. This is of particular interest after fire, where hydrochloric acid has inevitably been generated by combustion of chlorinated plastics such as PVC. Experience and observation suggested that the rate of corrosion after exhaustion of the original hydrochloric acid would be determined by how wet the metal surface is, and by the chloride concentration on the surface; and the wetting of the surface would depend on humidity and the nature of the chloride salt.

The discovery of the Hall‐Herqult process for the manufacture of aluminium made it possible to obtain the metal in large quantities. Soon it attained the position of a major industrial metal due to its lightness combined with strength, capacity to take up a high polish, excellent conductivity of heat and electricity. Moreover it gives a wide range of extremely valuable alloys with diverse elements such as copper, magnesium, nickel, silicon, zinc, etc.

Magnesium-aluminum layered double hydroxides (LDH) with a platelet-like morphology were synthesized through a modified co-precipitation method. The purpose of this paper is to investigate calcined Mg-Al-CO₃ LDH (CLDH) as chloride ion traps.

The morphology and chemical composition of the synthesized materials were studied through UHR-SEM, EDS, FT-IR and XRD. The chloride ion adsorption was confirmed by XRD; the characteristic diffraction peaks of the reconstructed LDH structure were revealed, similar to the one before the thermal treatment process. The effect of varying the experimental conditions on the chloride ion adsorption, such as the initial target-ion concentration, the adsorbent material dosage, the solution temperature and the solution pH was also investigated.

The experimental data fitting revealed that the Langmuir equation is a better model on the basis of correlation coefficients (R²) and that the pseudo-second kinetic model can satisfactorily describe the chloride ion uptake.

The ability of Mg-Al CLDH to recover their layered structure upon exposure to aqueous sodium chloride solutions with concentrations up to 0.3 M (10,636 mg/L) through the chloride adsorption and the simultaneous rehydration process is clearly demonstrated.

COPPER is by far the most important non‐ferrous metal used in industry. By virtue of its valuable physical and mechanical properties, long life, comparative cheapness and high scrap value, it occupies a position next only to iron and steel in commercial importance.

This paper aims to investigate the eco-friendly neodymium tartrate (NdTar) inhibitor for mild steel in sodium chloride (NaCl) solution.

The mild steel 1010 coupon was considered for the current study. Weight loss and the electrochemical methods were used to evaluate the inhibitory effects of neodymium chloride (NdCl₃) and NdTar on mild steel in NaCl solution. Scanning electron microscopy, energy-dispersive X-ray analysis and attenuated total reflectance-Fourier transform infrared spectroscopy measurements were carried out to study the morphology and composition of the film, nature of deposits and corrosion products formed in test media on the corroded steel, with the objective of further analyzing the observed behavior of the two inhibitors.

Of the two, NdTar performs better than NdCl₃ because it shields mild steel surfaces for longer. According to the results, when NdCl₃ is present in a corrosive solution, the protective film only comprises Nd/Fe oxide/hydroxide/carbonate. However, when neodymium is coupled with the tartrate group (an organic group) and then added to the NaCl solution, the inhibitor film comprises both bimetallic complexes (Fe-Tar-Nd) and metal oxide/hydroxide/carbonate, which results in a more compact film and has higher inhibition efficiency.

This study evaluated the combined effects of inorganic and organic inhibitors with those of an inorganic inhibitor used alone for mild steel in NaCl solution.