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MnFe2O4 nanoparticles were successfully synthesized via a simple sonochemical reaction by using 1-butyl-3-methylimidazolium bromide ionic liquid and cetyl trimethylammonium bromide as surfactant. MnFe2O4 nanoparticles with ionic liquid were added to polystyrene for preparation of magnetic polymeric nanocomposites. Structural, morphological, spectroscopic, magnetic and dielectric properties were investigated by means of transmission electron microscopy, X-ray powder diffractometry, Fourier transform infrared spectroscopy and vibrating sample magnetometry respectively. The results of thermogravimetric analysis indicated that the addition of MnFe2O4 nanoparticles with ionic liquid to polystyrene improved the thermal stability of the nanocomposite. The magnetization curves elucidate that the MnFe2O4 nanoparticles with ionic liquid/polystyrene nanocomposite has ferromagnetic behavior and improved saturation magnetization, coercivity and remanent magnetization. The electrical quantities such as dielectric constant (ε′), imaginary permittivity (ε″) and dielectric loss (tan (δ) = ε″/ε′) of MnFe2O4 nanoparticles and MnFe2O4 nanoparticles with ionic liquid/polystyrene nanocomposite were evaluated for temperature and frequency dependence. The obtained results are enhanced due to increase in the temperature and decreased with increasing frequency in MnFe2O4 nanoparticles with ionic liquid/polystyrene nanocomposite.

One of the main problems affecting the flow of cement bulk powder is the formation of cohesive arching at the outlet of the hopper, causing blockage of the silo opening and bridge formation. A simple concept is established which outlines these complications. In this context, the interactions of particles lead to a high degree of consolidation of the cement powder and an increase of adhesion force due to the small size and the large surface area of the cement particles. The results from the consolidation test and the flow properties (cohesion) show that the cement powder flow is mainly controlled by internal forces (Van der Waals and adhesion forces) and external forces. These forces have a direct influence on the powder structure, leading to a variable packing behaviour. Since the problem is attributable mainly to interparticle forces, before storage of the cement powder in the silo, the powder should be fluidised with air at a high velocity to disintegrate the cohesive structure and to overcome this undesirable property of cement flow.

In this work, two new para-xylyl linked bis-imidazolium Ionic Liquids (DILs), namely [p-C6H4(CH2ImMe)2][Cl−]2 and [p-C6H4(CH2ImMe)2+][BF4−]2, are prepared from imidazolium salts using a simple procedure in two steps. A computational study of the conformers of [p-C6H4(CH2ImMe)2], performed by means of DFT calculations with the 6-31G** basis set and the B3LYP theory, evidences that nine possible geometries of the cation are stable points of the potential energy surface and, therefore, could be experimentally found in real compounds. The infrared and Raman spectra of the nine conformers are calculated and compared to the experimental data. The occurrence of the trans configuration of the imidazolium rings in both compounds is strongly supported by this comparison. Finally, the cation-anion interactions were investigated in both DILs by means of NMR and Raman measurements, with a particular attention to the occurrence of hydrogen bonding. Both techniques indicate that hydrogen bonding is stronger in the sample containing Cl as anion. Moreover, the preferred site for hydrogen bonding is the C2 proton of the imidazolium ring; however, also the C(4) and C(5) protons of imidazolium, the methylene group and the phenyl ring participate to the hydrogen bonding.

International audience; Very recently, the hydroxyl-functionalized ionic liquids have gained immense interest and were developed for a number of interesting applications. In this work and for the first time new hydroxyl-functionalized namely; 1-(hydroxyethyl)-3-methylimidazolium dihydrogenophosphate ionic liquid [EtOHMIM+][H2PO4−] was synthesized in our laboratory. The synthesis is based on an alkylation reaction of 1-methylimidazole followed by anion exchange. The obtained IL is characterized by 1H-NMR, 13C-NMR spectroscopy. Their experimental vibrational spectroscopy have been investigated using Infrared and Raman spectroscopy, based on the infrared (IR) and Raman spectroscopies results, complete vibrational assignments have been performed. Besides, thermal properties of this hydroxyl-functionalized IL were investigated by using following techniques, (i) Thermogravimetric Analysis (TGA) and Derivative Thermogravimetry (DTG) in the temperature range from 20 to 600 C°, (ii) differential scanning calorimetry (DSC) from-100 °C to 200 °C. The thermogravimetry analysis was coupled with mass spectrometry in order to assess the influence of anion on the measured property

International audience; Egg shell (ES) is a biological macromolecule mainly containing calcite embedded in proteins and polysaccharides, while shell membrane predominantly contains proteins. Thus ES with membrane (ESM) possesses richer protein contents than ES. In the present work, ES and ESM have been separately modified using mono-and di-cationic imidazolium ionic liquids, [C 5 mim + ][Br-] (IL) and [Bis-(PhCH 2 MIm) + ][2Cl-] (DIL). Thus four modified products have been obtained namely ES-IL, ES-DIL, ESM-IL and ESM-DIL. In order to determine physico-chemical modifications of the ES due to the interactions with the ionic liquids, the structural, spectroscopic and thermal properties of all products were investigated by means of XRD, FTIR and TG/DTA. The IR spectra display significant changes in the 1400-1550 and 2800-3100 cm-1 regions confirming the insertion of IL and DIL into the ES and ESM layers. Furthermore, the XRD results indicate that this modification process influence the crystal structure of the ES. Thermal analysis suggests that the chemical modification increases the thermal stability of the ES and ESM. It has also been ascertained that presence of proteins in the shell membrane is responsible for increasing thermal stability in the order ES < ESM < ES-IL < ESM-IL < ES-DIL < ESM-DIL.

The chemical reaction of 2-chloroethanol with 1-vinylimidazol as precursor led to the corresponding compound 1-hydroxyethyl-3-vinylimidazolium chloride [EtOHVIM+] [Cl−]. In the next step, treatment of [EtOHVIM+][Cl−] with 2,2-azobisisobutyronitril (AIBN) afforded the poly1-(hydroxyethyl)-3-vinylimidazolium chloride (poly[EtOHVIM+][Cl−]), Finally, the reaction of (poly[EtOHVIM+][Cl−]) and sulfuric acid led to poly 1-(hydroxyethyl)-3-vinylimidazolium hydrogen sulfate (poly[EtOHVIM+][HSO4−]) by replacing the [Cl−] halide by an [HSO4−] anion. The structure of these compounds was identified by 1H NMR, 13C NMR as preliminary spectroscopic characterization. To obtain information on the structure and vibrational behavior in these compounds, vibrational spectroscopy measurements were investigated by Fourier Transform-Infrared-Attenuated Total Reflectance and Fourier Transform Raman spectroscopy in the spectral range 600–4000 cm−1 and 4000–500 cm−1, respectively. The Polymerization of IL gave rise to specific marks in the Raman and IR spectra and enhanced its vibrational property. Also, in order to understand the thermal stability in these compounds, the results concerning the melting point, glass transition and decomposition were determined by thermogravimetric analysis (TGA), differential thermal (DTG), and differential scanning calorimetry (DSC). The results indicated that the poly [EtOHVIM+][HSO4−] compound showed interesting thermal properties like high temperature of degradation and low temperature of glass transition compared to poly[EtOHVIM+][Cl−].

In this study, a new para‑xylyl linked di‑imidazolium [p‑C6H4(CH2ImMe)2+] ionic liquid (DIL) containing the bis(trifluoromethanesulfonyl)imide [(CF3SO2)2N−] anion is synthesized. The method is based on the alkylation reaction of 1‑methyl imidazole, followed by anion exchange. The obtained DIL is characterized by 1H NMR, 13C NMR, 19F NMR and FT-IR spectroscopy. The melting point and the subsequent decomposition of [p‑C6H4(CH2ImMe)2+][(CF3SO2)2N−]2 are measured by using differential scanning calorimetry (DSC) and thermogravimetric (TGA) analyses in the temperature range from 25 to 700 °C. Thermal analysis indicated that this DIL melted below 100 °C and can, therefore, be classified as an ionic liquid. Vibrational spectroscopy studies were conducted by infrared (IR), Raman (FT-Raman) spectroscopy and DFT calculations. Moreover, the crystal structure is investigated by single crystal X-ray diffraction (XRD) method. The X-ray studies on [p‑C6H4(CH2ImMe)2+][(CF3SO2)2N−]2 show that it crystallizes in the monoclinic system with space group P21/c. The theoretical structural parameters such as bond lengths, bond angles and dihedral angles determined by DFT methods are in good agreement with the XRD results.

This paper presents a self-reconfiguring MPPT to maximize the power extracted from solar photovoltaic panels. The proposed method is based on the reconfiguration of solar photovoltaic panels; it is particularly suitable for real-time recovery of power losses from DC-DC buck-converter during the variation of the resistive load value. The developed algorithm changes the disposition of panels in series and in parallel according to the needs. The simulation results show the reliability of the developed method.

In this study, we synthesized two ionic liquids based on imidazolium: one is a monocationic and the other is a dicationic. They are respectively 1-Propyl-3-methylimidazolium bromide ([PrMIM + ][Br − ]) and trimethylene bis-methylimidazolium bromide ([M(CH 2 ) 3 IM 2+ ][2Br − ]). The structures of these two ionic liquids which are composed of ions with atoms of the same nature were first identified by 1 H, 13 C NMR, and then compared in a study by FT-RAMAN and FTIR/ATR spectroscopies. FT-RAMAN spectras of the dicationic ionic liquid are richer in modes in the different spectral regions. Hence this richness seems to be a consequence of the passage from one to two rings in the imidazolium cation. In particular, the vibrational modes in the spectral ranges 700–600 cm −1 , 1700–1500 cm −1 and 3200–2700 cm −1 by FTIR/ATR seem to be sensitive to the change from mono to dicationic than in FT-RAMAN. The spectral range in which the intermolecular interactions are present (200-50 cm −1 ) is a marker of differentiation between the mono and the dicationic. The spectral ranges on 1700–1200 cm −1 and 3200–2700 cm −1 also show signs of upheaval between our two samples. We can also notice that there are much more active modes in FT-RAMAN spectroscopy than in FTIR/ATR spectroscopy.

A new geminal di-cationic ionic liquid (IL) containing a central cationic unit methylidene capped by a basic functionality (imidazole) is synthesized. The compound was characterized by means of1H,13C,19F NMR, IR and Raman spectroscopies and its crystal structure is confirmed by single crystal X-ray diffraction method. The X-ray studies on ([M(CH2)IM2+][2NTf $_{2}^{-}$ ]) show that it crystallizes in monoclinic system with space group: P 21/c. Thermal properties were investigated in the temperature range from 0 to 400∘C by using differential thermal (DTA) and thermogravimetric (TGA) analyses. The frequency-dependent electrical data are discussed using complex dielectric permittivity in the frequency range of (10−2–106 Hz) and in the temperature range of −50∘ to 20∘C. The outstanding dielectric and thermal properties make this IL as promising candidate for electrochemical devices.

International audience; We have used the imidazole as a starting compound for the preparation of a new ionic liquid 1-(hydroxyethyl)-3-methylimidazolium sulfate, with a yield of 98% in the two-steps synthesis. This new ionic liquid at room temperature exhibits a greater chemical activity. For the first step, we change the previous synthetic route using 2-chloroethanol as starting material, and with 1-methylimidazole to prepare the 1-(hydroxyethyl)-3-methylimidazolium chloride [EtOHMIM+][Cl-]. In the second stage, we have exchanged the anion Cl- with HSO4-. The ionic liquid shows reasonably high conductivity and thermal stability up to 340 degrees C. Our samples are characterized by H-1 NMR, C-13 NMR and FT-IR. The physical characteristics of the ionic liquid, such as solvation capacity were studied using a thermo-gravimetric Analyzer (NETZSCH DSC 204 F1) in the range of 40-400 degrees C. The results show that the Its may be used as polyelectrolyte for electrochemical applications. (C) 2016 Elsevier B.V. All rights reserved.

Ionic liquids (ILs) are liquid salts of differentiating to all molten salts with temperature below 100° C (arbitrarily set with reference to the boiling point of water), but a large number of them are liquids at room temperature. The properties of ionic liquids such as their wide field of electro activity, their high conductivity, and high thermal stability have made them new prime candidates in searching for a new energy systems (photovoltaic cell, battery, solar concentrator ...). The present work objective is to study the physicochemical properties of some ionic liquids based on imidazolium ([BMIM]+ [BF4]-, [BMIM]+[PF6]-, [HMIM]+ [Br] -,[BMIM]+ [Br]−) and more particularly the dielectric properties. We performed measurements by dielectric spectroscopy to see the influence of the size of the anion and the length of the alkyl chain of the cation on the conductivity of ionic liquids at different temperatures. We made also theoretical study by using data mining techniques such as the analytical method principal components (PCA), that help us to study the relationships between variables (σ RT (S / m), Tg (K) lnσ∞ (S / m), B, T0 (K), m) and their relation with ionic liquids structure.

This paper develops characterization of graphene and ionic liquids in order to develop material, which allows several applications like sensors and energy storage. Several steps were applied in order to synthesise Nano-sensor. First, we synthesised Oxide Graphene. We mix ionic liquids with (GO) in order to maximise conductivity. We add new elements like the toxic substance tetrahydrofuran, which that it was adsorbed by GO-IL. This new material constitutes needs to product the Sensor based on ionic liquid functionalized graphene modified electrode for sensitive detection of Tetrahydrofuran.

The chemical and physical properties of imidazolium-based ionic liquids are determined by the interactions between the counter-ions. The C(2) position plays an important role in these interactions, as it represents the predominant site for interionic hydrogen bonding. This study shows that the directional hydrogen bonds between highly symmetrical anions (iodide, tetrafluoroborate, hexafluorophosphate) and the C(2)-H group of the 1-methyl-3-propylimidazolium cation determine the molecular and macroscopic behavior in terms of the thermal properties. Upon replacing the C(2) proton by a methyl group, the anion repositions itself at the C(4)/(5) moiety, where it forms a new hydrogen bond, apparently with only one of the two CH groups. In addition, the larger the anion is in diameter, the more likely it will establish further interactions with other parts of the cation, such as the propyl chain.

In this study, two ionic liquids containing the bis(trifluoromethanesulfonyl)imide ( $$[(\hbox {CF}_{3}\hbox {SO}_{2})_{2}\hbox {N}^{-}]$$ ) anion are synthesized. The syntheses are based on an alkylation reaction of 1-methyl imidazole and 1,2-dimethyl imidazole followed by anion exchange. The obtained ILs are characterized by $$^{1}\hbox {H-NMR}$$ , $$^{13}\hbox {C-NMR}$$ , $$^{19}\hbox {F-NMR}$$ and FT-IR spectroscopy. Vibrational spectroscopy studies were conducted by infrared (FTIR/ATR), Raman spectroscopy and DFT calculations. The presence of methylation in the C2 position gives rise to specific marker bands in the Raman and IR spectra. In order to ascertain whether cation conformers are present in our ionic liquids, a computational study was performed using the density functional theory. The comparison of the experimental data and the computed spectra shows that three conformers of the imidazolium ions are present in both ionic liquids. Synopsis We synthesized and investigated the vibrational properties of two ionic liquids, namely, 1-methyl,3-propyl imidazolium bis(trifluoromethane-sulfonyl) imide ( $$[1\hbox {-MPrIM}^{+}][(\hbox {CF}_{3}\hbox {SO}_{2})_{2}\hbox {N}^{-}]$$ ) and 1,2-dimethyl,3-propyl imidazolium bis(trifluoromethane-sulfonyl) imide ( $$[1,2\hbox {-DMPrIM}^{+}][(\hbox {CF}_{3}\hbox {SO}_{2})_{2}\hbox {N}^{-}]$$ ). Methylation in the C2 position gives rise to specific marker bands in the Raman and IR spectra. The comparison of the experimental data and the computed spectra at DFT level shows that three conformers of the imidazolium ions are present in both ionic liquids.

Imidazolium-based ionic liquids (ILs) are usually synthesized using non-ionic imidazole compounds as precursors. While the ILs have been extensively studied in the past, the precursors was not paid much attention to. The structural analysis of the precursors, however, may offer an opportunity to better understand the behavior of the ionic compounds of interest. In this paper, a comparative study of two ionic liquids and their imidazole precursors is presented. The precursors 1-methylimidazole [1-MIM] and 1,2-dimethylimidazole [1,2-DMIM] are compared in order to explain the influences of the methyl group at the C(2) position (methylation). Since the imidazole compounds are non-ionic, the spectroscopic properties of [1-MIM] and [1,2-DMIM] are not affected by cation-anion interactions. In addition, the products obtained by alkylation using propyl iodide leading to the corresponding IL compounds 1-methyl-3-propylimidazolium iodide [1-MPrIM + ][I − ] and 1,2-dimethyl-3-propylimidazolium iodide [1,2-DMPrIM + ][I − ] were studied. For this purpose, vibrational spectroscopy in terms of FT-Raman and FTIR in the wavenumber range from [45 to 3500 cm −1 ] and from [600 to 4000 cm −1 ], respectively, was performed. Moreover, to aid the spectral assignment, density functional theory (DFT) calculations were carried out. The aim was to investigate the vibrational structure, to understand the effects of the propyl group at the N(3) and of the methyl group at the C(2) position, and to analyze the resulting cation-anion interactions. The data indicate that the iodide ion predominantly interacts with the C(2) H group via hydrogen bonding. Upon methylation, the C(4/5) H moiety becomes the main interaction site. However, an interaction takes place only with one of the two hydrogen atoms resulting in a split of the initially degenerate CH stretching modes.

The reaction of lithium bis(trifluoromethanesulfonyl)imide with tetraphenylphosphonium bromide in water leads to the formation of tetraphenylphosphonium bis(trifluoromethanesulfonyl)imide ([PPh 4 + ][(CF 3 SO 2 ) 2 N − ]). The obtained compound was identified by means of 1 H, 13 C, 19 F and 31 P NMR spectroscopy. Although it has a structure similar to ionic liquids, it exhibits a melting point above 100 °C. Besides describing the synthesis, a detailed characterization of its conductivity and vibrational spectroscopic properties is presented. For the latter, FT-Raman and FTIR/ATR spectroscopies are used in the wavenumber range from 150 to 3500 cm −1 and from 600 to 3500 cm −1 , respectively. Density functional theory calculations reveal a minor influence of the interionic interactions on the vibrational structure. Consequently, the computational vibrational spectra of the isolated ions show a good agreement with the experimental data. A detailed vibrational assignment is presented. Furthermore, the conductivity data indicate a solid-solid phase transition about 130 K below the melting point.

A junction of emeraldine salt (ES [BF4 −]) doped by [BMIM] [BF4] may be preferred over the other junctions due to its low ideality factor and maximum rectification ratio. Schottky barrier diode based on composite of polyaniline (ES [BF4 −]) with polystyrene has been created and characterized using aluminium as Schottky contact and argent as an ohmic contact. The observed current–voltage characteristics can be satisfactorily fitted using the modified Schottky equation. Capacitance–voltage (C–V) in reverse bias and current–voltage (I–V) plots indicates a rectification. Various junction parameters were calculated from the temperature dependent I–V and C–V data and discussed. These results indicate that the composite materials have better mechanical strength and diode quality compared to the pure semiconducting polymer.

International audience; The ability to stabilize the sensitivity of a magnetoresistance sensor in unstable thermal environments is a key parameter in many high precision measurements. Here, we propose a method to stabilize the sensitivity of a highly sensitive and low noise magnetic sensor based on a planar Hall Effect crossed junction. The stability is achieved by controlling the interplay between Zeeman energy, exchange bias energy, and anisotropy energy as a function of the temperature of the sensor stack comprising a trilayer structure NiFe/Cu/IrMn (10/0.12/10 nm). The high thermal stability of the sensor sensitivity of 4.5 ± 0.15 × 10−3 V/A/T/K is achieved when the external magnetic field is set around ±2 ± 0.04 mT and the applied current is fixed at 20 mA in the temperature range of 110 K–360 K. This method improves the magnetic sensor detection by about an order of magnitude, enabling its deployment in various research fields, particularly to study magnetic properties of small quantities of magnetic materials toward the detection of single magnetic objects, which was impossible before.

Two new dicationic ionic liquids were synthesized: bis-methyl imidazolium methylidene hexafluorophosphate [M(CH2)IM2 +][2PF 6 − ] and bis-methyl imidazolium propylidene hexafluorophosphate [M(CH2)3IM2 +][2PF 6 − ]. Their structures were identified by H, C, P, F NMR, FTIR/ATR, and FT-Raman spectroscopies in order to study the effect of cation alkyl chain length on vibration behaviors. Several changes were recorded, which were related to alkyl chain length. A frequency shift was observed in some modes while others remained insensitive. A greater number of peaks was found in the FTIR/ATR spectra and the FT-Raman spectra with increasing alkyl chain length, which indicated that chain length influences the N–C connection twisting. More peaks with strong intensity appeared for longer alkyl chain lengths.

In this paper, we present a new approach for estimating the one-diode model parameters of a photovoltaic solar panel according to the irradiance and temperature. These parameters are given, at a known irradiance and temperature, from the knowledge of three operating points: short circuit, open circuit, and maximum power. In the first step, the adopted approach concerns the resolution of the system of equations constituting the three operating points to write all the model parameters according to series resistance. Secondly, we make an iterative resolution at the optimal operating point by using the Newton--Raphson method to calculate the series resistance value as well as the model parameters. Once the last ones are identified, we consider other equations for taking into account the irradiance and temperature effect. The simulation results show the convergence speed of the model parameters and the possibility of visualizing the electrical behavior of the panel according to the irradiance and temperature. With the identified model, we can develop algorithms of maximum power point tracking and make simulations of PV systems.

Ionic liquids like 1-butyl-3-methylimidazolium chloride ([BMIM] Cl, 1-butyl-3-methyl-imidazolium hexafluorophosphate [BMIM] PF6, 1-butyl-3-methyl-imidazolium tetrafluorobrate [BMIM] BF4, 1-butyl-3-methyl-imidazolium bis (trifluoromethylsulfonyl) imide [BMIM] NTf2) were used as doping elements in polyaniline. Pure polyaniline (EB) and polyaniline doped with different anions of ionic liquids (ESs) were chemically synthesized using ammonium peroxydisulphate (APS) and ionic liquids as oxidants. Junctions have been prepared by evaporating chalcogenide materials (ZnSe, CdSe) on conducting polyaniline (EB & ESs) pellets using a vacuum evaporation technique. I-V characteristics of junctions have been studied at room temperature using the Keithley electrometer 6517A. I-V measurements show the rectification effect. A junction of ES [BF4 −] anion may be preferred over the other junctions due to its low ideality factor and maximum rectification ratio.

In a previous paper, we investigated the comparison between monocationic and dicationic ionic liquids. In this study three new dicationic ionic liquids were synthesized, labeled: bis-methyl imidazolium methylidene iodide [M(CH2)IM2+][2I−], bis-methyl imidazolium methylidene hexafluorophosphate [M(CH2)IM2+][2PF6−], bis-methyl imidazolium methylidene bis (trifluoromethanesulfonyl) imide [M(CH2)IM2+][2NTf2−]. In order to study the effect of the nature of the anion on the vibrational behaviors, their structures were identified by H, C, P, F NMR, FTIR/ATR and FT-RAMAN spectroscopies. However, we observe very different vibrational modes between ionic liquids following the chosen anion. According to the type of anion, the interaction anion–cation is translated by different intensities for the same vibrational mode, by frequency shifts and by appearance of modes specific to the anion.

In this study, we synthesised a dicationic ionic liquids labeled bis-methyl imidazolium methylidene bis (trifluoromethanesulfonyl) imide ([M(CH2)IM2+][ 2 NTf 2 - ]). The structure was identified by NMR. In order to characterise this ionic liquid, vibrational spectroscopy studies were performed by FTIR/ATR and FT-Raman spectroscopies. A comparative study was introduced by FTIR/ATR and FT-Raman spectroscopies, between our synthesised dicationic ionic liquid and a monocationic ionic liquid ([EMIM+][ NTf 2 - ]), where the anion and the cation are similar. FTIR/ATR spectra of dicationic ionic liquid are richer in modes especially in the spectral range of 3000 cm−1. In the 1400–900 cm−1 spectral region, the mode corresponding to the vibration of the NTf 2 - anion at 1040, 1140 and 1340 cm−1 is very sensitive by the number of cation change. It was also the case for the peak at 1575 cm−1 assigned to ring in-plane symmetric/anti-symmetric stretch CH2(N) and CH3(N)CN stretch. In the 4000–2800 cm−1 spectral region, we observed few new peaks for [M(CH2)IM2+] comparatively with [EMIM+]; a splitting for the peak at 3105 cm−1 and some wavenumber shifts for various modes. For the FT-Raman spectroscopy study, we realised our study in the spectral region 4000–0 cm−1 while that of the monocationique sample is realised in the spectral region 1700–200 cm−1. We observe in the common region 19 new peaks with the passage from the mono to dicationic, what is consequent. The impact of the passage from mono to dicationic is more important for the anion contribution spectral range (1400–300 cm−1) than in the FTIR/ATR spectroscopy study. Other markers of differentiation between [M(CH2)IM2+] and [EMIM+] are observed for vibrational modes assigned to CH2(N) and CH3(N)CN stretch. We can also notice a contrast between the two spectroscopies: there are more active modes in FT-Raman than in FTIR/ATR spectroscopy.

A new palladium-bidentate complex [m-C6H4(CH2ImMe)2(PdCl2)] (III) was prepared in two steps. In the first step, [m-C6H4(CH2ImMeAgCl)2] (II) (Im = imidazole moiety) was obtained by reacting imidazolium salt [m-C6H4(CH2ImMe)2]Cl2 (I) (prepared by quaternisation of Nmethylimidazole with 1,3-bis(chloromethyl)benzene) and Ag2O in CH2Cl2. In the next step, treatment of (II) with Pd(CH3CN)2Cl2 afforded complex III which was evaluated for its catalytic activity for C-C bond-formation reactions by examining the coupling reaction of 3-iodoanisole with phenylacetylene in the Sonogashira reaction. In addition, 3-methoxybiphenyls were obtained with good to excellent yields by Suzuki coupling reactions of 3-iodoanisole with phenylboronic acids or phenylborates salts in the presence of this complex.

International audience; The results obtained in this study showed that more than 80% of methylene blue (MB) was eliminated in the first five minutes with a neutral pH at 20°C and with the variable initial concentrations of MB between 5 and 30 mg/l in the presence of 1 g/l of clay. The clay of Maghnia flocculates in the presence of the MB in solution regardless of the strength of the pH of the medium. The optimal elimination of both MB (99%) and clay (98%) has been reached when mixing 120 mg/l of MB with 0.4–0.5 g/l of clay (FMC or SMC). The same result was obtained when mixing 20 mg/l of MB with 0.16–0.2 g/l of clay (FMC or SMC). Adding a suspension from the clay of Maghnia to the wastewater textile industry has proven effective. Second-order kinetic model represents well, this elimination with a coefficient of correlation R2 ranging between 0.9991 and 1.0. Freundlich, Temkin, and Dubinin–Radushkevich models showed that the temperature between 10 and 40°C does not have a great effect on this elimination. Thermodynamic parameters ΔG°, ΔH° and ΔS° indicated that the process is spontaneous with a weak energy.