The corrosion behavior of P110 casing steel in simulated concrete liquid and simulated annulus fluid was investigated to reveal the corrosion pattern and protective properties of corrosion products in the two environments. Potentiodynamic polarization curves, electrochemical impedance spectroscopy (EIS), Mott–Schottky tests, and electrochemical noise (EN) tests were used to study the corrosion behavior of P110 casing steel in simulated concrete liquid and simulated annulus fluid saturated with CO₂. Scanning electron microscopy (SEM) combined with Energy-Dispersive Spectrometer (EDS) mapping was used to characterize the corrosion morphology and elemental distribution of P110 casing steel. The results show that the corrosion resistance of P110 casing steel deteriorates with the increasing immersion days in the simulated annulus fluid, the impedance decreases gradually, and the corrosion-product film shows a loose and porous structure. In the simulated concrete liquid, under the condition of containing a low concentration of Cl⁻, the protection of the corrosion products gradually increases with the extension of immersion days. With the increasing concentration of Cl⁻ and the extension of immersion days, the electrochemical noise resistance and charge transfer resistance of P110 steel decrease gradually, and the protective property of the corrosion-product film decreases, which is capable of forming steady pitting corrosion.

In the process of petroleum exploitation, in order to effectively inhibit the corrosion damage of acid to metal equipment. Mannich base corrosion inhibitors are generally added to inhibit the corrosion damage of acid. In order to enhance the solubility of Mannich base corrosion inhibitor. This paper intends to introduce hydrophilic groups to enhance the solubility of the Mannich base corrosion inhibitor. In this paper, two efficient corrosion inhibitors 3-(2-hydroxyethylamino)-1-phenylpropan-1-one (MY1) and 3-(2-aminoethylamino)-1-phenylpropan-1-one (MY2), were synthesized based on the Mannich reaction, using formaldehyde, acetophenone and ethanolamine/ethylenediamine as reaction raw materials. The corrosion inhibition performance of the inhibitor on N80 steel in 15% (mass fraction) hydrochloric acid solution was studied by means of the static weight loss method, electrochemical test and optical contact angle analysis. It could be seen from the static weight loss method that the corrosion rate in the hydrochloric acid solution before and after adding 0.7% (mass fraction) corrosion inhibitor concentration decreased from 129.39 g·m⁻²·h⁻¹ to 1.45 g·m⁻²·h⁻¹ and 2.79 g·m⁻²·h⁻¹, respectively. The corrosion inhibition rate could reach 98%, indicating that both inhibitors had good corrosion inhibition performance, and the corrosion inhibition effect of MY1 was better than that of MY2. It was found from the electrochemical tests that the two inhibitors were mixed corrosion inhibitors mainly inhibiting the anodic reaction, and both inhibitors belonged to spontaneous adsorption, and their adsorption behaviors followed the Langmuir adsorption isotherm. In addition, the surface of N80 steel was characterized by SEM, EDS elemental mapping and contact angle measurement. The results show that a dense hydrophobic film is formed on the surface of the steel sheet after the addition of a corrosion inhibitor, which prevents corrosion.

The global energy crisis significantly raises the research on renewable energy materials and devices both in academic and industrial community. Besides the electrochemical energy such as batteries, the solar energy is another choice to develop renewable clean energy. During the last ten years, the perovskite solar cells (PSCs) has been a hot research topic and developed fast. However, large-scale production of PSCs is still hindered by the high cost of their fabrication process, because the perovskite films are known to be sensitive to oxygen and water. Therefore, developing a composition engineering in air for PSCs with high solar energy conversion efficiency is urgently required in the field. Herein, it is found that the crystallization and morphology of CH3NH3PbI3 (MAPbI(3)) perovskite films prepared in air are dependent on the processing methods. The perovskite grain size becomes larger when the concentration of CH3NH3I (MAI) solution was increased from 20 mg/mL to 70 mg/mL, which is beneficial for charge carrier transport and device performance. Thanks to the optimal perovskite fabrication process, the champion PSC has been fabricated in open air and it shows IP: 1193.14.78 On: Wed 26 Aug 2020 05 49:03 a power conversion efficiency (PCE) of 14.9%. More importantly, the PSC fabricated with our method shows Copyright: American Scientific Pubishers good stability. This work provides an effective composition engineering to fabricate PSCs in air with both high Delivered by ngenta PCE and stability.