Mohamed First University

Oujda, Morocco

Mohamed First University

Oujda, Morocco
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Gharibi E.,Mohamed First University | Jabri M.,Mohamed First University | Jabri M.,LafargeHolcim Company | Ramdani A.,Mohamed First University
Journal of Materials and Environmental Science | Year: 2017

In our study we have evaluated the effect of magnesium (Mg) insertion on the stability and the hydration process of tri-calcium silicate which is considered as the main phase of Portland cement clinker. We have concluded that the substitution of calcium by magnesium in the silicate phase involves several phenomena, such as a weak increase of portlandite (Ca(OH)2) rate, a diminution of the Ca/Si ratio and an augmentation of the average silicate chain lengths. In addition, we have concluded that these aspects are due only to the dopage of Mg into C3S and not to the alteration of its hydration mechanism. Then, we confirmed that the insertion of Mg is beneficial to maintain the stability of C3S. At first, we synthesized a pure and doped product with Mg and then studied the effect of Mg insertion on the stability and the hydration of C3S. Many investigation techniques have been used such as: X-ray diffraction XRD, thermogravimetric analysis TGA, differential Scanning Calorimetry DSC, nuclear magnetic resonance29Si MAS-NMR and Electron Probe Micro-Analyzer (EPMA). © 2017, University of Mohammed Premier Oujda Morocco.


Leouifoudi I.,Sultan Moulay Slimane University | Harnafi H.,Mohamed First University | Zyad A.,Sultan Moulay Slimane University
Advances in Pharmacological Sciences | Year: 2015

Natural polyphenols extracts have been usually associated with great bioactive properties. In this work, we investigated in vitro antioxidant and antimicrobial potential of the phenolic olive mill wastewater extracts (OWWE) and the olive cake extracts (OCE). Using the Folin Ciocalteux method, OWWE contained higher total phenol content compared to OCE (8.90 ± 0.728 g/L versus 0.95 ± 0.017 mg/g). The phenolic compounds identification was carried out with a performance liquid chromatograph coupled to tandem mass spectrometry equipment (HPLC-ESI-MS). With this method, a list of polyphenols from OWWE and OCE was obtained. The antioxidant activity was measured in aqueous (DPPH) and emulsion (BCBT) systems. Using the DPPH assay, the results show that OWWE was more active than OCE and interestingly the extracts originating from mountainous areas were more active than those produced from plain areas (E C 50 = 12.1 ± 5.6 g/mL; E C 50 = 157.7 ± 34.9 g/mL, resp.). However, when the antioxidant activity was reversed in the BCBT, OCE produced from plain area was more potent than mountainous OCE. Testing by the gel diffusion assay, all the tested extracts have showed significant spectrum antibacterial activity against Staphylococcus aureus, whereas the biophenols extracts showed more limited activity against Escherichia coli and Streptococcus faecalis. © 2015 Inass Leouifoudi et al.


PubMed | Mohamed First University and Sultan Moulay Slimane University
Type: | Journal: Advances in pharmacological sciences | Year: 2015

Natural polyphenols extracts have been usually associated with great bioactive properties. In this work, we investigated in vitro antioxidant and antimicrobial potential of the phenolic olive mill wastewater extracts (OWWE) and the olive cake extracts (OCE). Using the Folin Ciocalteux method, OWWE contained higher total phenol content compared to OCE (8.90 0.728g/L versus 0.95 0.017mg/g). The phenolic compounds identification was carried out with a performance liquid chromatograph coupled to tandem mass spectrometry equipment (HPLC-ESI-MS). With this method, a list of polyphenols from OWWE and OCE was obtained. The antioxidant activity was measured in aqueous (DPPH) and emulsion (BCBT) systems. Using the DPPH assay, the results show that OWWE was more active than OCE and interestingly the extracts originating from mountainous areas were more active than those produced from plain areas (EC50 = 12.1 5.6g/mL; EC50 = 157.7 34.9g/mL, resp.). However, when the antioxidant activity was reversed in the BCBT, OCE produced from plain area was more potent than mountainous OCE. Testing by the gel diffusion assay, all the tested extracts have showed significant spectrum antibacterial activity against Staphylococcus aureus, whereas the biophenols extracts showed more limited activity against Escherichia coli and Streptococcus faecalis.


PubMed | Mohamed First University and University of Paris Descartes
Type: Journal Article | Journal: Presse medicale (Paris, France : 1983) | Year: 2016

Laron syndrome is a rare cause of short stature due to an abnormality of growth hormone receptor (GHR). It is characterized by poor phenotype-genotype correlation and geographic predilection essentially in the Mediterranean rim, the Middle East and Indian subcontinent. This syndrome corresponds to an endogenous and exogenous complete insensitivity of GH and manifests by early hypoglycemia, an extremely severe short stature and dysmorphic features contrasting with high levels of circulating GH. To date, treatment with recombinant IGF1 is the only treatment option that has improved the terrible prognosis in these patients but does not actually realize the conditions for genuine replacement therapy.


Chergui A.,Mohamed first University | El Hafid L.,Mohamed first University | Melhaoui M.,Mohamed first University
Research Journal of Pharmaceutical, Biological and Chemical Sciences | Year: 2012

Though the soil of coastal areas of the Nador lagoon is very rich in total limestone, it's very poor in nitrogen, in organic matter, in phosphorus (P2O5) and in active limestone. Furthermore the substrate of the beach and the fixed dunes are salty with a relatively high content of Potassium (K2O), while the embryonic dunes, mobile dunes and the semi fixed dunes are not salty and have a relatively low level of potassium. Besides, the distribution of coastal dune vegetation could be controlled by the Salinity level and the potassium concentration.


Hirech K.,Mohamed First University | Melhaoui M.,Mohamed First University | Yaden F.,Mohamed First University | Baghaz E.,Mohamed First University | Kassmi K.,Mohamed First University
Energy Procedia | Year: 2013

In this article, we present the results related to the design, the realization and the experimentation of an autonomous PV system equipped with a solar regulator and digital MPPT command. The solar regulator controls the state of charge of batteries, and in the same time the energy supplied by photovoltaic panels is optimized to the maximum independently of weather. This late function is ensured by a DC/DC converter of Boost-type and a digital MPPT command based on the use of a microcontroller. The results obtained during days with weather perturbations, showed the robustness of the PV system (stability, optimal functioning of PV panels), the good control of charge of batteries under the maximum of energy supplied by the PV panels, according to three phases, determinate the state of charge and the protection against the overcharge and the deep discharge. © 2013 The Authors. Published by Elsevier Ltd.


Baghaz E.,Mohamed First University | Melhaoui M.,Mohamed First University | Yaden F.,Mohamed First University | Hirech K.,Mohamed First University | Kassmi K.,Mohamed First University
Energy Procedia | Year: 2013

In this paper, we present experimental results of a photovoltaic system (PV) provided with two analog and digital MPPT commands. The disadvantage of these commands is that they are suffering from divergence problems caused by a sudden change in weather conditions (light, temperature,) or load variations. Therefore, we developed a CDCS circuit for the analog MPPT command to optimize the reliability of PV system independently of weather conditions changes or load variations. The functioning of the PV system during whole days shows a very good agreement between the experiment and the optimal simulation of the electric properties of the PV panel (voltage, current and power). The low losses of electrical energy produced by the PV panel (lower than 5 %) and the smooth functioning of the DC/DC converter used (efficiency upper to 80 %) reveal the good functioning and reliability of the systems using both types of MPPT commands conceived and realized during this work. © 2013 The Authors. Published by Elsevier Ltd.


Hirech K.,Mohamed First University | Melhaoui M.,Mohamed First University | Malek R.,Mohamed First University | Kassmi K.,Mohamed First University
Lecture Notes in Electrical Engineering | Year: 2016

In this work, we present the results concerning the design, implementation and test of a photovoltaic installation with two regulation systems, one is a commercial regulator and the other is designed in this work. This latter optimizes the installation operation by a new approach with improved control blocks: MPPT, charging/discharging process, estimates the state of charge and manages the energy between blocks. The regulation systems experiment during 4 days with weather disturbances shows the robustness of the designed one which improves the battery life: the accuracy and speed on the maximization of the power supplied by panels, precision of the state of charge estimation, improvement of the energy management at the charge/discharge. © Springer International Publishing Switzerland 2016.


Mezroui S.,Mohamed First University | Azizi A.,Mohamed First University | Ziane M.,Mohamed First University
International Conference on Multimedia Computing and Systems -Proceedings | Year: 2014

Buchmann and Williams presented in 1988 a key exchange system based on the quadratic imaginary fields. In this paper, we introduce a key exchange protocol based on some imaginary biquadratic fields which is inspired by the Buchmann-Williams' method. We also give the theoretical method in order to generalize the Buchmann-Williams protocol to other fields extensions. © 2014 IEEE.


Chergui A.,Mohamed first University | El Hafid L.,Mohamed first University | Melhaoui M.,Mohamed first University
Journal of Materials and Environmental Science | Year: 2011

The bordering dunes in Saidia are coastal habitats of great ecological importance. The most typical plant is Ammophila arenaria (or Marram Grass) which plays numerous ecological roles. One of these roles is the fixation of sand. The anatomy and the physiognomy of this plant enable it a perfect adaptation for hydric and salt stress in these dunes. The marram grass develops on a sandy soil structure. The moisture of this substrate increases with the depth while the salinity decreases. The intensity of these two factors varies according to the climatic conditions. In the experimental conditions, a sandy ground with daily watering yields a better vegetal growth of the Marram Grass starting from Cuttings of rhizomes.

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