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The processed discharges from Tangier Automotive City’s (TAC) Chrafate Wastewater Treatment Plant (WWTP) contaminate the Jouamaa Hakama groundwater and the Ouljat Echatt river. We aimed to study the unknown interactions between surface water (SW) and groundwater (GW). A total of nine Jouamaa Hakama GW samples and eleven Ouljat Echatt SW samples were taken and analyzed in 2021 and 2022 to determine 16 physical and chemical parameters (pH, temperature (T), electrical conductivity (EC), dissolved oxygen (DO), total hardness (TH), turbidity (TURB), and total dissolved solids (TDS), cations: Na+, K+, Mg2+ and Ca2+, anions: Cl−, CO32−, HCO3−, NO3−, and SO42−). For exploitation of the data, we used a methodology based on hydrochemical modeling (HM), principal component analysis (PCA), Water Quality Index (WQI), Irrigation Water Quality Index (IWQI), inverse distance weighted interpolation (IDW) using Geographic Information Systems (GIS), and regression analysis (RA). We studied the interaction of the surface water of the river (contaminated by discharges from the WWTP) with the shallow groundwater on a strip of 100 m on either side of the river to understand the transverse and longitudinal dispersion of this pollution The investigations indicated that the major ions found in GW and SW were characterized in a different order in the anion list order Cl− > CO32− > NO3− > HCO3− > SO42− and Cl− > SO42− > CO32− > NO3− > HCO3−, respectively, while the concentrations of cations showed the same order for both: Na+ > Ca2+ > Mg2+ > K+. As a result, GW showed in the Piper diagram the type of sodium chloride to magnesium carbonate, while SW belongs to the sodium chloride to magnesium sulfate type. The WQI showed that the river waters are all unsuitable for use (WQI > 100), while the GW is of poor quality (WQI > 76). Moreover, the results of the GW–SW interaction along the river revealed a significant relationship (R2 = 0.85), which means that strong circulation and the infiltration of contaminated SW into shallow GW occur in this area. The approaches followed have been proven effective in evaluating water quality for human and animal uses. These results can help decision-makers in the region take suitable management measures to mitigate this environmental problem.

Consumption of polluted water has harmful impacts on human health. This study examined the quality of groundwater in the Benslimane area for drinking purposes based on the Water quality index (WQI), Nitrate pollution index (NPI), and Total risk quotient (THQ) for different age groups. A total of 120 groundwater samples were collected for physicochemical analyses. The results showed WQI values ranging from 157.7 to 472.7 and an average of 279.4, with a total absence of water of excellent or good quality, and about 62.5% of the groundwater samples were of very poor quality for consumption. Nitrate concentrations ranged from 1 to 270 mg/L with an average of 64 mg/L, and 56.7% had values above the World Health Organization safety level of 50 mg/L. The NPI showed that 78.3% of the sampled sites showed very high pollution as a result of intense anthropogenic activities. High contamination is observed in the north and east of the region for arboriculture, grapes, maize, and vegetables as opposed to cereals. The health risk associated with nitrates, based on oral exposure, was much higher than dermal contact. The total risk quotient for both pathways was 0.02 to 6.58, 0.02 to 6.12, 0.06 to 17.06, and 0.05 to 13.35 for women, men, children, and infants, respectively. A total of 65, 63.3, 82.0, and 78.3% of groundwater samples presented a non-cancer health risk for women, men, children, and infants, respectively. Therefore, this study can help identify contaminated areas in order to track corrective safety measures to control groundwater quality in the region and improve sanitary conditions.

The study of soil quality in irrigated areas is necessary to evaluate the sustainability of the agricultural production system. Indeed, the assessment of this quality is based on the physicochemical and biological characterization of soil parameters, as well as the knowledge of their spatial distribution and their evolution over time. This work aims to make a diagnosis of the current situation of soil quality of SidiYahya in the Gharb plain, Morocco. For this, sampling was carried out from 33 sites distributed over the studied plain during 2019. In this study, different soil properties including specifically texture, pH, electrical conductivity (EC), organic matter (OM), phosphorus (P2O5), and potassium (K2O) were measured while exchangeable sodium percentage (ESP) was calculated using the standard formula. Based on the observed soil properties a map was prepared by using a geographic information system (GIS), which was based specifically on the inverse distance weighted (IDW) spatial interpolation method. Data were processed using different statistical tools like descriptive statistics, correlation, and principal component analysis (PCA). Results of the study revealed that 70% of the soils have a heavy clayey texture with a predominance of vertisols (55%). Further, the study area soil is mainly alkaline (70%), poor in organic matter (61%) and phosphorus (52%), while very rich in potassium (70%), and non-saline (88%) contents. Soil pH was reported to be the least variable whereas sand, phosphorus, and salinity were the highest variable. IDW allowed mapping the soil properties by moving from punctual information to whole extent information. Furthermore, correlations were found between various soil properties by using PCA, 3 principal components (PCs) were able to extract 76% of the information from the 9 initial soil properties. Collected soil samples were grouped into 3 groups, based on their scores on the 3 PCs. Based on these two kinds of information, delineation of management zones can be established for a site-specific supply of agricultural inputs leading to better management of soil and water resources for securing their sustainable use.

Phosphate glasses of the ternary system Bi2O3-Nb2O5-P2O5 were studied in two compositional series, namely xBi2O3-5Nb2O5-(95−x)P2O5 (serie B), with x = 10–17,5 mol% Bi2O3, and 10Bi2O3−xNb2O5-(90−x)P2O5 (serie N), with x = 2,5–15 mol% Nb2O5. Seven homogeneous glassy samples were prepared, and their amorphous structure were confirmed by X-ray diffraction. The dielectric properties such as dielectric constant ( e ′ ) and dielectric loss (tanδ) were determined as a function of temperature ranging from 100 °C to 500 °C at a fixed applied frequency of 16 kHz. Replacing P2O5 by Bi2O3 or Nb2O5 decreases the dielectric parameters in both series. These results are attributed to the increase in the cross-link density and the rigidity of the glass, leading therefore to a decrease of the polarization. The usual increasing behavior of ( e ′ ) and (tanδ) with temperature may be explained by the augmentation of the orientation polarization and the electrical conduction losses values.

Conservation agriculture (CA) is characterized by three principles: minimum tillage, even the total absence of tillage in the case of direct seeding (NT), permanent soil cover by mulch, and diversification of crops. Its main objective is to control soil degradation by conserving the physical and biological properties and fertility of the soil, which leads to an improvement in productivity, while preserving the environment. Conventional tillage (CT) used in the arid and semi-arid environments of Morocco (particularly in the study site area of Merchouch) compromise the productivity of established crops in these regions. The work presented consists in the study of the impact of NT on the physico-chemical properties of the soil, especially organic matter (SOM), bulk density (BD), soil moisture (θg), and structural stability (SS) in semi-arid zones. The results show that the use of the NT system positively influences the accumulation of SOM, especially at the soil surface horizon (0-5cm). Concerning θg, there is a significant difference between the two treatments (NT and CT) at the average of the three depths and especially at the horizon 20-40 cm so NT increases the water retention capacity. This study also shows that the mean weight diameter (MWD) of the 3 tests (water, ethanol, and rehumectation) is higher for NT compared to CT. This shows that no-till helped to build a good soil structure over time, which is highly desirable for improving agricultural productivity and conserving natural resources, especially water.

In Morocco, agriculture is an important sector of the economy, accounting for 15 to 20% of Gross Domestic Product. However, it has faced several challenges: intensive tillage of land that has accelerated water erosion, seriously threatening water and soil potential, low plant cover density and misuse of traditional agricultural practices, causing a decrease in organic matter levels and destroying aggregate stability. Climate change is making water and soil management in agriculture more and more complicated. The major challenge for Moroccan agriculture is to increase agricultural production while preserving natural resources. The objective of our study is to evaluate the effect of no tillage (NT) on the physico- chemical properties of soil in the El Koudia experimental station, Rabat, Morocco. The crop is durum wheat, Arrehane variety. Soil samples are pre-dried, ground and screened to 0.2mm for organic matter (OM) analysis and 2mm for the remainder of the analyses. Plugs, canned, are then sintered, screened and dried for structural stability tests. The results show that no tillage (NT) favours the accumulation of surface OM, particularly at the 0-5cm horizon unlike conventional tillage (CT). The NT promotes structural stability, with a mean weight diameter (MWD) = 0.94mm for the NT compared to 0.83mm for the CT. These results show that soils ploughed in CT are more exposed to erosion degradation than soils not ploughed (NT). In addition, NT preserves soil moisture and promotes additional water retention of 5 to 10%.

Carbon steel is a commonly used alloy in petroleum refining equipment. Nonetheless, its weak corrosion resistance is a perpetual problem for these industries. In the present study, we manifest the usefulness of a novel 1,2,4-triazole derivative, namely 5-hexylsulfanyl-1,2,4-triazole (HST) in inhibiting the carbon steel (CS) corrosion in 1.0 M HCl using mass loss measurements, electrochemical, scanning electron microscopy coupled with X-ray detection (SEM-EDX), X-Ray diffraction (XRD) and computational techniques. We deduced from the gravimetric study that the optimal concentration of HST is 10−3 M. Its inhibition efficiency can reach 97 % based on electrochemical data. Electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization (PDP) results suggest an increased impedance in the presence of HST and mixed nature of inhibitor action, respectively. The compound HST mitigates corrosion at the temperature range of 298 K–338 K, with an inhibition efficiency of 89 % at 338 K. Free Gibbs energy obtained from the Langmuir isotherm model suggests that the inhibitor molecules hinder the acid attack mainly by chemisorption. A computational study based on Density Functional Theory (DFT) and Molecular Dynamics (MD) simulations was performed in an attempt to identify the factors most associated with anti-corrosive properties of the tested compound.

The performance of two 1,2,4-triazole derivatives bearing an alkyl chain of variable length named 5-octylsulfanyl-1,2,4-triazole (TR8) and 5-decylsulfanyl-1,2,4-triazole (TR10) against mild steel (MS) corrosion in 1.0 M HCl was first evaluated utilizing experimental methods such as weight loss (WL), electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization (PDP) techniques. Then, theoretical methods like Density Functional Theory (DFT) and molecular dynamics (MD) simulations were used to explore corrosion inhibition mechanisms. Effect of molecules on the MS surface was analyzed by scanning electron microscope (SEM) and atomic force microscopy (AFM). A correlation between corrosion inhibition properties and physicochemical and electronic properties as determined by DFT and MD was demonstrated. 1,2,4-triazole derivatives behave as effective inhibitors for MS corrosion in HCl at all concentrations tested with better efficacy at an optimal concentration of 10−3 M. The maximum inhibition efficiencies (based on EIS results) were obtained 92% and 88% for TR10 and TR8, respectively. The adsorption is following the Langmuir isotherm model. Theoretical studies clearly showed that differences in carbon chain length alter inhibition performances of inhibitors and were found to be compatible with experimental results.

Lithium–Lead–Bismuth phosphates glasses having, a composition 30Li 3 PO 4 –(70 − x )Pb 3 (PO 4 ) 2 – x BiPO 4 (45 ≤ x ≤ 60 mol%) were prepared by using the melt quenching method 1000 °C. The thermal stability of theses glasses increases with the substitution of Bi 2 O 3 with PbO. The ionic conductivity of all compositions have been measured over a wide temperature (200–500 °C) and frequency range (1–106 Hz). The ionic conductivity data below and above T g follows Arrhenius and Vogel–Tamman–Fulcher (VTF) relationship, respectively. The activation energies are estimated and discussed. The dependence in frequency of AC conductivity is found to obey Jonscher’s relation.

Some physicochemical properties such as surface tension, molar volume, density and viscosity of liquid Sn–Ag–Cu alloys have been calculated using Kohler, Muggianu, Toop and Hillert geometrical models along three cross-sections namely [Formula: see text]/[Formula: see text], 1/1 and 2/1. Indeed, Guggenheim, Kozlov–Romanov–Petrov and Kaptay equations have also been extended to estimate the surface tension and viscosity based on the thermodynamic data of the investigated system over wide temperature ranges of 823–1123[Formula: see text]K and 773–1173[Formula: see text]K, respectively. The results show that the three investigated properties, surface tension, density and viscosity, decrease with increasing tin for all studied models. On the other hand, a different behavior of these properties as a function of the temperature was noted. This evolution depends on the composition of the studied alloys. On the contrary, the molar volume increases with increase of temperature and tin compositions. It should be noted that the surface tension, density and molar volume show a linear dependence on temperature for all the investigated compositions. For viscosity, a curvilinear dependence has been observed. The calculated surface tensions and densities were compared with those reported experimentally for Sn–Ag–Cu alloys along the cross-section [Formula: see text]/[Formula: see text][Formula: see text]1/1.

In this paper, some geometrical models such as Kohler, Muggianu, Toop, and Hillert have been used to estimate the molar volume of Au–Bi–Sn ternary systems based on the data of sub-binary systems over a wide temperature range (673–973[Formula: see text]K). The density of Au–Bi–Sn alloys was calculated from the calculated molar volume and using theoretical equation along three cross-sections [Formula: see text]/[Formula: see text]/2, 1/1 and 2/1. In addition, the viscosity of Au–Bi–Sn alloys was calculated by using Seetharaman–Sichen equation over a wide temperature range (673–1273[Formula: see text]K). The density of these alloys show linear dependence on temperature for all investigated compositions, while the molar volumes increase with increasing temperature and Sn compositions. The results show, as a function of temperature, that the increase in concentration of tin influences the viscosity of the Au–Bi–Sn alloys. The calculated values of density of Au–Bi–Sn alloys are compared with the experimental values reported in the literature, and a good agreement was observed.

A series of hexa(alkylsulfonyl)benzenes were studied electrochemically in aprotic media at a platinum electrode. It was found that the voltammetric behaviour strongly depends on the bulkiness of the alkyl groups as well as on parameters like temperature and/or sweep rate. It is pointed out that the title compounds can exist in two forms possessing quite different standard potentials. The ratio between these two structures is strongly influenced by an inner structure reorganization following electron transfer.

o-Bis(alkylsulfonyl)benzenes taken as disulfonylbenzene model substrates lead unexpectedly, under cathodic reduction performed in aprotic media in the presence of an excess of alkyl halide, to an alkylation concomitantly with a monocleavage reaction. The formation mechanism of these alkylated aromatic monosulfones is discussed on the basis of an electron-transfer reaction between the sulfone anion radical and the organic halide followed by a radical coupling. Comportement e′lectrochimique des polysulfones aromatiques. II. Re′duction cathodique des o-bis(alkylsulfonyl)benzenes en milieu aprotique en pre′sence d'haloge′nures aliphatiques. Les o-bis(alkylsulfonyl)benzenes pris comme substrats modeles des disulfonylbenzenes conduisent, de facon inattendue, lors de leur re′duction cathodique en milieu aprotique en pre′sence d'un exces d'haloge′nure d'alkyle, a une alkylation concomitante a la re′action de monoclivage. Le me′canisme de formation de ces monosulfones aromatiques alkyle′es, base′ sur une re′action de transfert d'e′lectron entre le radical anion de la sulfone et l'haloge′nure organique suivi par un couplage radicalaire, est discute′.

The electrochemical reduction of the carbene 1 reversibly yielded the corresponding radical anion 2 , which was characterized by ESR measurements. Ab initio calculations provided a better understanding of its structure and stability.

Bulky hexa[alkylsulfonyl] benzenes are considered to be strong π-acceptors. They are reduced in totally irreversible processes quite unexpectedly when compared with other aromatic tri-, tetra- and pentasulfonyl benzenes. Electron transfer could favor a structural change in relation to the extreme bulkiness of these substrates.

In this paper, the surface tension, molar volume and density of liquid Ag–Cu–Sn alloys have been calculated using Kohler, Muggianu, Toop, and Hillert models. In addition, the surface tension and viscosity of the Ag–Cu–Sn ternary alloys at different temperatures have been predicted on the basis of Guggenheim and Seetharaman–Sichen equations, respectively. The results show that density and viscosity decrease with increasing tin and increasing temperature for the all studied models. While the surface tension shows a different tendency, especially for the Kohler and Muggianu symmetric models. On the other hand, the molar volume increases with increase of temperature and tin compositions. The calculated values of surface tension and density of Ag–Cu–Sn alloys are compared with the available experimental values and a good agreement was observed.

Phosphine-borane complexes are very stable reagents. When borane is added to the phosphene, these complexes have a reactivity similar to phosphine-oxide. Alkylation reactions and olefination reactions (Horner type 1 ) with these complexes are easily obtained.