M. El Moudane - Academia.edu (original) (raw)
Papers by M. El Moudane
Inorganic Chemistry Communications
Inorganic Chemistry Communications
Journal of Alloys and Compounds
Inorganic Chemistry Communications
Pb-free solders: Surface tension calculation of the Ag-Bi-Sn ternary alloys at 873 K R. M´Chaar 1
The glass forming region has been determined in the ternary system BiPO4-NbOPO4P2O5. Glasses with... more The glass forming region has been determined in the ternary system BiPO4-NbOPO4P2O5. Glasses with compositions xBiPO4-(90-x)P2O5-10NbOPO4 (20x35 mol%) and 20BiPO4-(80-x)P2O5-xNbOPO4 (5x30 mol%) were prepared. Their physical, electrical and structural such as density, molar volume, ionic conductivity and FT-IR spectroscopy have been studied in order to understand the structural role of Bi2O3 and Nb2O5 in these glasses. The density of these glasses increases and their molar volume decreases with Bi2O3 and Nb2O5 contents. FT-IR study shows absorption peaks around 1200 cm, 1100 cm, 1000 cm, 900 cm, 780-730 cm, and 520-480 cm corresponding to (PO2)s, (PO3)as, (PO3)s, (P-O-P)as, (P-O-P)s and the bending vibration () of P-O bonds, respectively. The ionic conductivity diminishes substantially with increasing concentration of either Bi2O3 or Nb2O5. The variation in is related to the decrease in O concentration, their mobilty and in the glass network polarization. A correlation betwe...
Glasses with composition 20K2O-xMnO-(80-x)P2O5 with 0≤ x ≤30 mol% were prepared by conventional m... more Glasses with composition 20K2O-xMnO-(80-x)P2O5 with 0≤ x ≤30 mol% were prepared by conventional melt quenching technique at 1100°C mixtures of K2CO3, MnCO3 and NH4H2PO4. Their density, molar volume, glass transition temperature and infrared spectroscopy have been investigated. Differential Scanning Calorimetry (DSC) measurements give the variation of glass transition temperature (Tg) from 225°C for x=0 to 440°C for x=30 mol %. The density () measurements increase from 2.28 to 2.89 g.cm -3 . The evolution of infrared spectra with the composition is studied and the oxide forming character is discussed. When manganese oxide is added to potassium phosphate glass, phosphate chains are depolymerized by the incorporation of distorted (4) units through P-O-Mn bonds. it is assumed to be presented as [MnO4/2] 2structural units a corner sharing geometry and the electrical neutrality in the system is achieved by the conversion of [POO3/2] into [PO4/2] + units.
The results of the calculation of integral enthalpies of mixing in liquid state for ternary Au-In... more The results of the calculation of integral enthalpies of mixing in liquid state for ternary Au-In-Zn alloys using the general solution model of Chou are presented in this paper. Five selected sections with xIn/xZn = 1/3, 1/2, 1/1, 2/1 and 3/1 were investigated at 973K. The other traditional geometric models such as Kohler, and Toop are also included in calculations for comparison and discussion. The Kohler-values are more exothermic than those obtained by Toop’s model. The results obtained by Chou’s model show that Au-In-Zn ternary system is asymmetric.
Surface tensions of the Ag-Bi-Sn ternary system alloys are calculated from the surface tensions o... more Surface tensions of the Ag-Bi-Sn ternary system alloys are calculated from the surface tensions of the Ag-Bi, Ag-Sn and Bi-Sn sub-binary systems by using geometric models (Kohler, Toop and Hillert). At the same time, the surface tension of the Ag-Bi-Sn ternary alloys at 873K and their sub-binary systems are predicted on the basis of Butler’s equation in combination with thermodynamic data. Except for the asymmetric Toop and Hillert models, the agreement between the calculated results and experimental data is quite good using Kohler and Butler’s models. With increasing amount of Bismuth the surface tension decreases slightly. The rich-silver cross-section shows that silver has no appreciable effect on increasing the surface tension.
In this paper, the general solution model of Chou has been used to predict the integral enthalpie... more In this paper, the general solution model of Chou has been used to predict the integral enthalpies of mixing of liquid In-SnZn ternary alloys in five selected sections, xIn/xSn = 0.15/0.85, 0.34/0.66, 0.50/0.50, 0.67/0.33 and 0.85/0.15. The other traditional models such as Kohler, Muggianu, Toop and Hillert are also included in calculations. Comparison with literature data was done and showed reasonable agreement with Toop and Hillert asymmetric models.
The results of the calculation of integral enthalpies of mixing in liquid state for ternary Ag-In... more The results of the calculation of integral enthalpies of mixing in liquid state for ternary Ag-In-Zn alloys using the general solution model of Chou are presented in this paper. Five selected sections with xIn/xZn = 1/1, 1/2, 2/1, 1/3 and 3/1 were investigated at 773K. The other traditional geometric models such as Kohler, Muggianu, Toop and Hillert are also included in calculations for comparison and discussion.
The partial and integral enthalpies of mixing of liquid binary Bi-Ni alloys were determined at 12... more The partial and integral enthalpies of mixing of liquid binary Bi-Ni alloys were determined at 1273 and 1573 K. The calorimetric measurements were carried out using two different calorimeters. A Calvet-type twin microcalorimeter system (HT-1000) was used for T = 1273 K with a drop calorimetric technique. For higher temperature T = 1573 K a multi High-Temperature micro-calorimeter (MHTC) has been used with a manual drop. The experimental data at 1273 and 1573 K have been compared to each other and to the assessed results available in the literature. Finally, the experimental binary data were evaluated by means of a standard RedlichKister polynomial fit.
The surface tensions, viscosities and molar volumes of liquid Ag-Bi-Sn alloys were calculated and... more The surface tensions, viscosities and molar volumes of liquid Ag-Bi-Sn alloys were calculated and presented in this paper. These physical properties have been estimated using the Kohler’s model for surface tension and molar volume and Seetharaman’s model for viscosity. The calculations were done along three selected sections with xSn/xBi = 1/2, 1/1 and 2/1 at different temperatures from 873 to 1273 K. The results show that up to 40 at. % Ag, no influence of the surface tension and no significant dependence on temperature has been noted. With increasing temperature the viscosity decreases smoothly. Both surface tension and viscosity increase significantly at high Ag-concentrations. The molar volume decreases linearly with increasing Ag-compositions and the calculated values are similar to those of additive molar volumes. Received 20 June 2016 Revised 05 Mar 2017 Accepted 09 Mar 2017
This paper deals with the investigation of the electrical conductivity and dielectric properties,... more This paper deals with the investigation of the electrical conductivity and dielectric properties, including dielectric constant (ε'), dielectric losses (tanδ) and ionic conductivity (ζ) as a function of temperature ranging from room temperature to 540 °C at a fixed applied frequency of 100 kHz for some phosphate glasses in the ternary K2O-MnO-P2O5 system. The compositions chosen for the study are (50-x)K2O-xMnO-50P2O5 (20-35 mol%) and xK2O-20MnO-(80-x)P2O5 (15-30 mol%), which were prepared by the conventional melt quenching technique. The amorphous nature of the samples was asserted by X–ray diffraction. The values of the dielectric parameters (viz., ɛ', tan δ and ζ) decrease by increasing manganese oxide concentration and increase by increasing temperature. The observed decrease in the dielectric parameters, with increasing amount of MnO, can be explained as the result of formation of more compact and integrated glass structure, leading to a decrease of the polarization. Th...
Silybum Marianum oil (SMO) was tested as corrosion inhibitor for carbon steel in 1 M HCl using po... more Silybum Marianum oil (SMO) was tested as corrosion inhibitor for carbon steel in 1 M HCl using potentiodynamic polarization (PDP), electrochemical impedance spectroscopy (EIS) and scanning electron microscope (SEM). The effect of temperature on the corrosion behavior of carbon steel in 1 M HCl with addition of SMO was studied in the temperature range of 303-333 K. The experimental results reveal that SMO has a good inhibiting effect on the metal tested in 1 M HCl solution. Potentiodynamic polarization (PDP) studies clearly reveal that it acts essentially as a mixed mode of action. The protection efficiency increases with increasing of inhibitor concentration to attain 89.1 % at 3g L -1 . EIS results show that the charge transfer resistance Rct increases with increasing of SMO concentration. The change in the impedance parameters (Rct and Cdl) with concentration of SMO is indicative of the adsorption of molecules leading to the formation of a protective layer on the surface of carbon...
Results of thermodynamic predicting methods applied to the quaternary metallic X-In-Sn-Zn (X = Ag... more Results of thermodynamic predicting methods applied to the quaternary metallic X-In-Sn-Zn (X = Ag and Au) systems based on their sub-binary systems are presented in this work. The general solution model of Chou has been used to estimate the integral enthalpies of mixing of the investigated systems. The other traditional models such as Muggianu and Toop are also included in estimations for comparison. The estimations were carried out at 773 K along five starting ternary compositions InxSnyZnz with additions of Ag or Au. In the Ag-In-Sn-Zn system, the estimated enthalpies of mixing using Chou’s model are close to those predicted by a symmetric Muggianu’s model, while for the Au-In-Sn-Zn, the values obtained by Chou’s model are in good agreement with those of an asymmetric Toop’s model.
The inhibiting effect of essential oil of Carum Carvi (Carum.C) on the corrosion of carbon steel ... more The inhibiting effect of essential oil of Carum Carvi (Carum.C) on the corrosion of carbon steel in 1M HCl solution has been investigated by different techniques such as weight loss, potentiodynamic polarization and electrochemical impedance (EIS) methods at different concentrations of inhibitor ranging from 0,6 to 3 g/L. Essential oil from Carum Carvi was obtained by Clevenger-type water distillation. The essential oil was identified by gas chromatography-mass Spectrometry (GC and GC/MS). The major compounds identified are: Carvone (67.3 %) and Limonene (28.8 %). The results of polarization show that the inhibition efficiency increases with increasing the Carum.C oil concentration to attain a maximum value of 92 % at 3 g/L. The Nyquist plots showed also that increasing oil concentration, charge-transfer resistance increased and double-layer capacitance decreased, involving increased inhibition efficiency. The study of the effect of the temperature (303 343 K) on the behavior of the...
Chemical Data Collections
MATEC Web of Conferences
Homogeneous phosphate glasses having the general formula 20K 2 O-xMnO-(80-x)P 2 O 5 were synthesi... more Homogeneous phosphate glasses having the general formula 20K 2 O-xMnO-(80-x)P 2 O 5 were synthesized using a melt-quenching method. The amorphous nature of the samples was asserted by X-ray diffraction. The glasses are studied in order to evaluate the influence of MnO addition on the chemical and mechanical properties, such as, dissolution rate, average compressive strength (Rc), Young's modulus (E) and limit strain (Ɛ lim). Some studies show that the addition of MnO significantly reduces the degradation rate (D R) of soluble phosphate glasses and enhanced chemical stability of both alkali-resistance and acid-resistance. MnO interfere with the chemical structure of the glass, and consequently improve their mechanical properties. Indeed, the mechanical measurements showed that the glass structure was modified by the addition of MnO oxide, becoming more rigid, and as a result, increasing the compressive strength (Rc), Young's modulus (E). These new materials could be an important opportunity for applications in the fields of building, construction, civil engineering, etc…
Materials Today: Proceedings
Inorganic Chemistry Communications
Inorganic Chemistry Communications
Journal of Alloys and Compounds
Inorganic Chemistry Communications
Pb-free solders: Surface tension calculation of the Ag-Bi-Sn ternary alloys at 873 K R. M´Chaar 1
The glass forming region has been determined in the ternary system BiPO4-NbOPO4P2O5. Glasses with... more The glass forming region has been determined in the ternary system BiPO4-NbOPO4P2O5. Glasses with compositions xBiPO4-(90-x)P2O5-10NbOPO4 (20x35 mol%) and 20BiPO4-(80-x)P2O5-xNbOPO4 (5x30 mol%) were prepared. Their physical, electrical and structural such as density, molar volume, ionic conductivity and FT-IR spectroscopy have been studied in order to understand the structural role of Bi2O3 and Nb2O5 in these glasses. The density of these glasses increases and their molar volume decreases with Bi2O3 and Nb2O5 contents. FT-IR study shows absorption peaks around 1200 cm, 1100 cm, 1000 cm, 900 cm, 780-730 cm, and 520-480 cm corresponding to (PO2)s, (PO3)as, (PO3)s, (P-O-P)as, (P-O-P)s and the bending vibration () of P-O bonds, respectively. The ionic conductivity diminishes substantially with increasing concentration of either Bi2O3 or Nb2O5. The variation in is related to the decrease in O concentration, their mobilty and in the glass network polarization. A correlation betwe...
Glasses with composition 20K2O-xMnO-(80-x)P2O5 with 0≤ x ≤30 mol% were prepared by conventional m... more Glasses with composition 20K2O-xMnO-(80-x)P2O5 with 0≤ x ≤30 mol% were prepared by conventional melt quenching technique at 1100°C mixtures of K2CO3, MnCO3 and NH4H2PO4. Their density, molar volume, glass transition temperature and infrared spectroscopy have been investigated. Differential Scanning Calorimetry (DSC) measurements give the variation of glass transition temperature (Tg) from 225°C for x=0 to 440°C for x=30 mol %. The density () measurements increase from 2.28 to 2.89 g.cm -3 . The evolution of infrared spectra with the composition is studied and the oxide forming character is discussed. When manganese oxide is added to potassium phosphate glass, phosphate chains are depolymerized by the incorporation of distorted (4) units through P-O-Mn bonds. it is assumed to be presented as [MnO4/2] 2structural units a corner sharing geometry and the electrical neutrality in the system is achieved by the conversion of [POO3/2] into [PO4/2] + units.
The results of the calculation of integral enthalpies of mixing in liquid state for ternary Au-In... more The results of the calculation of integral enthalpies of mixing in liquid state for ternary Au-In-Zn alloys using the general solution model of Chou are presented in this paper. Five selected sections with xIn/xZn = 1/3, 1/2, 1/1, 2/1 and 3/1 were investigated at 973K. The other traditional geometric models such as Kohler, and Toop are also included in calculations for comparison and discussion. The Kohler-values are more exothermic than those obtained by Toop’s model. The results obtained by Chou’s model show that Au-In-Zn ternary system is asymmetric.
Surface tensions of the Ag-Bi-Sn ternary system alloys are calculated from the surface tensions o... more Surface tensions of the Ag-Bi-Sn ternary system alloys are calculated from the surface tensions of the Ag-Bi, Ag-Sn and Bi-Sn sub-binary systems by using geometric models (Kohler, Toop and Hillert). At the same time, the surface tension of the Ag-Bi-Sn ternary alloys at 873K and their sub-binary systems are predicted on the basis of Butler’s equation in combination with thermodynamic data. Except for the asymmetric Toop and Hillert models, the agreement between the calculated results and experimental data is quite good using Kohler and Butler’s models. With increasing amount of Bismuth the surface tension decreases slightly. The rich-silver cross-section shows that silver has no appreciable effect on increasing the surface tension.
In this paper, the general solution model of Chou has been used to predict the integral enthalpie... more In this paper, the general solution model of Chou has been used to predict the integral enthalpies of mixing of liquid In-SnZn ternary alloys in five selected sections, xIn/xSn = 0.15/0.85, 0.34/0.66, 0.50/0.50, 0.67/0.33 and 0.85/0.15. The other traditional models such as Kohler, Muggianu, Toop and Hillert are also included in calculations. Comparison with literature data was done and showed reasonable agreement with Toop and Hillert asymmetric models.
The results of the calculation of integral enthalpies of mixing in liquid state for ternary Ag-In... more The results of the calculation of integral enthalpies of mixing in liquid state for ternary Ag-In-Zn alloys using the general solution model of Chou are presented in this paper. Five selected sections with xIn/xZn = 1/1, 1/2, 2/1, 1/3 and 3/1 were investigated at 773K. The other traditional geometric models such as Kohler, Muggianu, Toop and Hillert are also included in calculations for comparison and discussion.
The partial and integral enthalpies of mixing of liquid binary Bi-Ni alloys were determined at 12... more The partial and integral enthalpies of mixing of liquid binary Bi-Ni alloys were determined at 1273 and 1573 K. The calorimetric measurements were carried out using two different calorimeters. A Calvet-type twin microcalorimeter system (HT-1000) was used for T = 1273 K with a drop calorimetric technique. For higher temperature T = 1573 K a multi High-Temperature micro-calorimeter (MHTC) has been used with a manual drop. The experimental data at 1273 and 1573 K have been compared to each other and to the assessed results available in the literature. Finally, the experimental binary data were evaluated by means of a standard RedlichKister polynomial fit.
The surface tensions, viscosities and molar volumes of liquid Ag-Bi-Sn alloys were calculated and... more The surface tensions, viscosities and molar volumes of liquid Ag-Bi-Sn alloys were calculated and presented in this paper. These physical properties have been estimated using the Kohler’s model for surface tension and molar volume and Seetharaman’s model for viscosity. The calculations were done along three selected sections with xSn/xBi = 1/2, 1/1 and 2/1 at different temperatures from 873 to 1273 K. The results show that up to 40 at. % Ag, no influence of the surface tension and no significant dependence on temperature has been noted. With increasing temperature the viscosity decreases smoothly. Both surface tension and viscosity increase significantly at high Ag-concentrations. The molar volume decreases linearly with increasing Ag-compositions and the calculated values are similar to those of additive molar volumes. Received 20 June 2016 Revised 05 Mar 2017 Accepted 09 Mar 2017
This paper deals with the investigation of the electrical conductivity and dielectric properties,... more This paper deals with the investigation of the electrical conductivity and dielectric properties, including dielectric constant (ε'), dielectric losses (tanδ) and ionic conductivity (ζ) as a function of temperature ranging from room temperature to 540 °C at a fixed applied frequency of 100 kHz for some phosphate glasses in the ternary K2O-MnO-P2O5 system. The compositions chosen for the study are (50-x)K2O-xMnO-50P2O5 (20-35 mol%) and xK2O-20MnO-(80-x)P2O5 (15-30 mol%), which were prepared by the conventional melt quenching technique. The amorphous nature of the samples was asserted by X–ray diffraction. The values of the dielectric parameters (viz., ɛ', tan δ and ζ) decrease by increasing manganese oxide concentration and increase by increasing temperature. The observed decrease in the dielectric parameters, with increasing amount of MnO, can be explained as the result of formation of more compact and integrated glass structure, leading to a decrease of the polarization. Th...
Silybum Marianum oil (SMO) was tested as corrosion inhibitor for carbon steel in 1 M HCl using po... more Silybum Marianum oil (SMO) was tested as corrosion inhibitor for carbon steel in 1 M HCl using potentiodynamic polarization (PDP), electrochemical impedance spectroscopy (EIS) and scanning electron microscope (SEM). The effect of temperature on the corrosion behavior of carbon steel in 1 M HCl with addition of SMO was studied in the temperature range of 303-333 K. The experimental results reveal that SMO has a good inhibiting effect on the metal tested in 1 M HCl solution. Potentiodynamic polarization (PDP) studies clearly reveal that it acts essentially as a mixed mode of action. The protection efficiency increases with increasing of inhibitor concentration to attain 89.1 % at 3g L -1 . EIS results show that the charge transfer resistance Rct increases with increasing of SMO concentration. The change in the impedance parameters (Rct and Cdl) with concentration of SMO is indicative of the adsorption of molecules leading to the formation of a protective layer on the surface of carbon...
Results of thermodynamic predicting methods applied to the quaternary metallic X-In-Sn-Zn (X = Ag... more Results of thermodynamic predicting methods applied to the quaternary metallic X-In-Sn-Zn (X = Ag and Au) systems based on their sub-binary systems are presented in this work. The general solution model of Chou has been used to estimate the integral enthalpies of mixing of the investigated systems. The other traditional models such as Muggianu and Toop are also included in estimations for comparison. The estimations were carried out at 773 K along five starting ternary compositions InxSnyZnz with additions of Ag or Au. In the Ag-In-Sn-Zn system, the estimated enthalpies of mixing using Chou’s model are close to those predicted by a symmetric Muggianu’s model, while for the Au-In-Sn-Zn, the values obtained by Chou’s model are in good agreement with those of an asymmetric Toop’s model.
The inhibiting effect of essential oil of Carum Carvi (Carum.C) on the corrosion of carbon steel ... more The inhibiting effect of essential oil of Carum Carvi (Carum.C) on the corrosion of carbon steel in 1M HCl solution has been investigated by different techniques such as weight loss, potentiodynamic polarization and electrochemical impedance (EIS) methods at different concentrations of inhibitor ranging from 0,6 to 3 g/L. Essential oil from Carum Carvi was obtained by Clevenger-type water distillation. The essential oil was identified by gas chromatography-mass Spectrometry (GC and GC/MS). The major compounds identified are: Carvone (67.3 %) and Limonene (28.8 %). The results of polarization show that the inhibition efficiency increases with increasing the Carum.C oil concentration to attain a maximum value of 92 % at 3 g/L. The Nyquist plots showed also that increasing oil concentration, charge-transfer resistance increased and double-layer capacitance decreased, involving increased inhibition efficiency. The study of the effect of the temperature (303 343 K) on the behavior of the...
Chemical Data Collections
MATEC Web of Conferences
Homogeneous phosphate glasses having the general formula 20K 2 O-xMnO-(80-x)P 2 O 5 were synthesi... more Homogeneous phosphate glasses having the general formula 20K 2 O-xMnO-(80-x)P 2 O 5 were synthesized using a melt-quenching method. The amorphous nature of the samples was asserted by X-ray diffraction. The glasses are studied in order to evaluate the influence of MnO addition on the chemical and mechanical properties, such as, dissolution rate, average compressive strength (Rc), Young's modulus (E) and limit strain (Ɛ lim). Some studies show that the addition of MnO significantly reduces the degradation rate (D R) of soluble phosphate glasses and enhanced chemical stability of both alkali-resistance and acid-resistance. MnO interfere with the chemical structure of the glass, and consequently improve their mechanical properties. Indeed, the mechanical measurements showed that the glass structure was modified by the addition of MnO oxide, becoming more rigid, and as a result, increasing the compressive strength (Rc), Young's modulus (E). These new materials could be an important opportunity for applications in the fields of building, construction, civil engineering, etc…
Materials Today: Proceedings