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The corrosion of metals poses a threat to the economy, the environment, and human health due to undesirable reactions and contaminated products. Corrosion inhibitors, including natural products, can play a key role in protecting metallic materials, especially under challenging conditions. In this study, the roots of the Inula viscosa plant were examined for their ability to act as corrosion inhibitors in a 1 M hydrochloric acid (HCl) solution. Different extracts of the plant were evaluated for their corrosion inhibition capacity in a 1 M HCl solution. The effectiveness of different plant extracts was assessed, including an aqueous extract, an ethanolic extract, and a combined water–ethanol extract. Compounds present in the roots of Inula viscosa were identified using high-performance liquid chromatography. The electrochemical properties of the extracts were studied using various techniques such as open circuit potential, electrochemical impedance spectroscopy, and potentiodynamic polarization. Additionally, surface analysis after immersion was performed using scanning electron microscopy. Electrochemical data revealed that Inula viscosa root (IVR) extracts acted as mixed-type corrosion inhibitors with pronounced cathodic characteristics. The inhibitory efficiency was closely related to the concentration of Inula viscosa (I. viscosa), showing a significant increase with higher concentrations. This resulted in a decrease in corrosion current and an increase in polarization resistance. Notably, inhibitory efficiency reached high levels, up to 97.7% in mixed extract which represents a mixture between water and ethanol. In our study, it was observed that the mixed extract (water + ethanol) allowed for a greater corrosion inhibition compared to the other solvents studied, 97.7%. Surface analyses confirmed the formation of an organic film layer on the steel surface, attributed to the bonding of functional groups and heteroatoms in I. viscosa components. Therefore, this study paves the way for the potential integration of I. viscosa as a promising corrosion inhibition material, offering durable protection against steel corrosion and opening avenues for various related applications.

Under sustainable development conditions, water quality and quantity play a crucial role in meeting basic human needs. To meet the growing demand for water, surface water quality management is an important aspect. Consequently, water quality must be monitored and assessed via the use of innovative techniques, such as water quality index (SEQ-Water).For that purpose, water quality of Oued Fez catchment areas was evaluated according to Moroccan water quality guidelines by using the weighted quality index (SEQ-Water), physicochemical parameters, trace elements and bacteriological characterization. Five Sites were chosen after a diagnosis based on different criteria such as activity and density of population. These sites were Amont oued Fez (S1), Oued Fez (S2), Oued Ljawahir (S3), Oued Tgat (S4) and Oued Ain Smen (S5). Physicochemical quality was determined by evaluating Chemical Oxygen Demand (COD), total Kjeldhal nitrogen (NTK), suspended solids (SS), nitrates (NO3-), nitrites (NO2-), ammonium (NH4+), sulphates (SO42-), total phosphorus (TP) and trace elements (Cr, Cd, Cu, Ni, Co, Pb and Zn). Bacteriological analyses were carried out by testing enumeration of total coliforms (TC) and fecal coliforms (FC).Except Oued Ain Smen, physico-chemical parameters exceed by far the Moroccan standards of surface water quality. High concentrations of Se, Cd, Pb and As were detected. Fecal and total coliforms were also present at all sites, and varied from 1150 CF/100 mL to 100,000 CF/100 mL. All results were statistically validated with a p value

Aromatic and medicinal plants in ecosystems are subject to various climatic disturbances that impact their morphological and physiological processes. Although plants have mechanisms to adapt to their climatic conditions, such as periods of drought and lack of precipitation, their metabolism is still affected. This study aimed to predict and evaluate the behavior of Salvia officinalis under climatic disturbances. Over a period of 4 years in a controlled environment, three treatments were applied to the plant: Treatment 1 with normal monthly average temperature and precipitation in the first year; Treatment 2 with a temperature increase of 5°C and a 50% reduction in water supply in the second year; and Treatment 3 with a temperature increase of 10°C and a 75% reduction in water supply in the fourth year. The results show that the percentage of primary metabolites, including nutritional values, changed with increasing temperature and decreasing precipitation. Treatment 1 had 7.13% protein, 6.21% carbohydrate, 1.35% lipid, and 4% dietary fiber, while Treatment 2 had 7.05% protein, 5.12% carbohydrate, 1.01% lipid, and 3.01% dietary fiber, and Treatment 3 had 6.86% protein, 3.02% carbohydrate, 0.52% lipid, and 2.34% dietary fiber. The mineral composition of the plant also changed with each treatment, with Mg decreasing from 10.02 to 8.55 to 0.05%, Fe decreasing from 8.18 to 8 to 7.62%, K decreasing from 5.55 to 5.05 to 4.02%, Mn decreasing from 5.54 to 5.11 to 3.48%, Ca decreasing from 4.65 to 2.75 to 1.23%, and P decreasing from 3.37 to 3.05 to 2.25%. Regarding secondary metabolites, the percentage of alkaloids, flavonoids, saponins, coumarins, tannins, and essential oil yield changed as well. Treatment 2 showed an increase in secondary metabolites, while Treatment 3 showed a decrease. Alkaloids increased from 9.56 to 13.68 to 11.3%, flavonoids increased from 7.53 to 13.48 to 10.49%, saponins increased from 5.23 to 7.44 to 6%, coumarins increased from 3.35 to 4.85 to 3.99%, tannins increased from 2.26 to 3.22 to 2.62%, and essential oil yield increased from 0.53 to 0.80 to 0.62%. Gas chromatography analysis revealed that the major compounds of the essential oils of Salvia officinalis, such as α-thujone, manool, β-caryophyllene, α-humulene, viridiflorol, 1,8-cineol, and camphor, were also modified by temperature and water stress.

Two novel ecological ionic-liquid derivatives based on imidazolium (ILs), namely, 3-(2-ethoxy-2-oxoethyl)-1-phenethyl-1H-imidazol-3-ium-chloride [OE-IM+, Cl-] and 3-(4-ethoxy-4-oxobutyl)-1-phenethyl-1H-imidazol-3-ium-chloride [OB-IM+, Cl-] was studied by Electrochemical Impedance Spectroscopy (EIS), Potentiodynamic Polarization (PP), SEM/EDX analysis and theoretical calculations. It is found that the studied ionic liquids exhibit high inhibition performance for Mild steel (MS) in 1 M HCl. Hence the formation of a barrier layer that retards redox reactions and therefore prevents the corrosion process of MS. Inhibition efficiency for all the compounds increases with their concentration and follows the order [OE-IM+, Cl-] < [OB-IM+, Cl-], indicating effective performance was achieved as the length of the alkyl chain attached to the imidazolium ring extended. Furthermore, DFT and MD simulations were used, revealing the impact of molecular configuration on the anticorrosive properties of these chemicals. [ABSTRACT FROM AUTHOR]

As a corrosion inhibitor for mild steel in a molar hydrochloric acid medium, we investigated the potential of Eucalyptus globulus essential oil (EuEO). Through electrochemical impedance spectroscopy (EIS), potentiodynamic polarization curves, and theoretical methods, including DFT/B3LYP 6-31G (d, p) and Monte Carlo simulations, the interactions between the EuEO components and the steel surface were analyzed. D-Allose, Betulinaldehyde, and Uvaol were identified as the major active compounds in the GC-MS analysis. The experimental results showed that EuEO reached an inhibitory efficiency as high as 97% at a 1 g/L concentration. The findings suggest that EuEO operates as a mixed-type inhibitor, reducing both cathodic and anodic reactions, as well as building up a protective coating on the steel surface. Simulations also confirmed that EuEO molecules function as electron donors and acceptors, enhancing corrosion resistance. [ABSTRACT FROM AUTHOR]

This research investigates the adsorption potential of pine cone powder (PCP) for the removal of copper ions (Cu(II)) from aqueous solutions. The process of adsorption was reasonably fast, completed within a time of 60 min. The pseudo-second order kinetic model describes properly the Cu(II) adsorption by PCP. The adsorbent was characterised by various instrumental techniques and batch experiments were conducted to investigate the effect of PCP dose, solution pH, particle size and initial Cu(II) concentration on adsorption efficiency. Optimum Cu(II) removal occurred at a slightly acidic pH, with a particle size less than 100 μm. The effective PCP dose was estimated to be 36 g L-1. The increase in the initial concentration of Cu (II) was accompanied by a reduction in the rate of its reduction by almost half. The Langmuir model was the best fitting isotherm with a maximum adsorption capacity of 9.08 mg g-1. The thermodynamic parameters values showed that the Cu(II) adsorption was a spontaneous and endothermic process. The results of this research suggest that Cu(II) could be removed through an environmentally friendly process using PCP as low-cost natural waste.