Les Critères d’Indexation dans le Directory of Open Access Journals (DOAJ)

Le DOAJ est le répertoire international des revues académiques en libre accès et évaluées par des pairs. Il couvre toutes les revues scientifiques et universitaires, dans toutes les disciplines et dans plusieurs langues. Devenu un outil incontournable, le DOAJ contribue efficacement à la diffusion de la science à travers l’inclusion dans sa plateforme des revues, en accès libre, qui adhèrent aux critères de qualité, d'ouverture et de transparence. Dans cet article, nous citerons les critères exigés aux revues pour être intégrées dans le répertoire de DOAJ. Ces revues font l'objet d’une expertise de la part l’équipe de DOAJ selon plusieurs critères de qualité et d'ouverture

ﻛﯾﻔﯾﺔ ﻧﺷر ﺑﺣﺛك وﻓﻘﺎً ﻟﻧظﺎم اﻟوﺻول اﻟﺣر

ﻛﯾﻔﯾﺔ ﻧﺷر ﺑﺣﺛك وﻓﻘﺎً ﻟﻧظﺎم اﻟوﺻول اﻟﺣر ﻣﺟﺎﻧﺎ و ﺑطرﯾﻘﺔ ﻗﺎﻧوﻧﯾ

How to make your research open access ( Arabic version)

ﻛﯾﻔﯾﺔ ﻧﺷر ﺑﺣﺛك وﻓﻘﺎً ﻟﻧظﺎم اﻟوﺻول اﻟﺣر ﻣﺟﺎﻧﺎ و ﺑطرﯾﻘﺔ ﻗﺎﻧوﻧﯾ

Directory of Open Access Journals (DOAJ): mise au point sur les critères d'indexation des revues

<p>•Introduction</p> <p>•Présentation succinct de DOAJ</p> <p>•Mission de DOAJ</p> <p>Le processus d’évaluation d’une revue scientifique par le DOAJ</p> <p>• Les critères d’indexation dans le DOAJ</p> <p>• Les critères basiques sur le contenu du site web de la revue</p> <p>• Les critères sur le contenu de l’article publié dans la revue</p> <p>• Comment choisir une revue pour publier vos travaux de recherche?</p> <p>Recommandations</p

Nouveaux alliages zinc-terres rares pour des applications anticorrosion (élaboration, propriétés et traitements de surfaces)

De nouveaux alliages Zn-TR1-5 %mass.(TR = Ce, La et Mischmetal : Ce 75%/La25%) ont été synthétisés par fusion sous atmosphère contrôlée et coulés sous forme de plaques. Dans ces nouveaux matériaux, les terre rare sont localisées exclusivement dans des phases intermétalliques dispersées de manière homogène dans la matrice de zinc : Zn11Ce, Zn13La ou Zn11Ce1-xLax and Zn13CeyLa1-y. Le comportement électrochimique de ces nouveaux alliages a été étudié dans un milieu corrosif de référence simulant les conditions atmosphériques. En parallèle, les phases intermétalliques pures Zn11Ce and Zn13La ont été synthétisées et leur influence électrochimique a été évaluée par voltamétrie et couplage galvanique. Les résultats montrent que les deux phases intermétalliques sont des sites cathodiques préférentiels de la réduction du dioxygène et induisent une inhibition cathodique de la corrosion des alliages Zn-TR par rapport au zinc pur. Ce phénomène est plus marqué dans le cas des alliages au lanthane. Dans le cas spécifique des alliages au cérium, une inhibition anodique a également été observée et corrélée avec une modification chimique des produits de corrosion (composés majoritairement d'hydrozincite). En fait, une faible quantitéhomogène de cérium a pu être mise en évidence dans la couche de corrosion par spectrométrie dispersive en longueur d'onde. D'après les résultats d'expériences de précipitation contrôlée de sels de cérium et zinc en milieu carbonaté, la présence de cérium dans la couche de corrosion et son caractère protecteur pourraient être attribués à la formation d'un composé mixte double lamellaire zinc-cérium. L'addition de moins de 2%mass. de cérium ou lanthane permet d'améliorer la résistance à la corrosion du zinc. Cependant, lorsque la teneur en terre-rare augmente, l'effet de couplage galvanique devient plus important et rend les alliages moins résistants que le zinc purNew Zn-RE1-5 wt.% alloys (RE=Ce, La and Mischmetal: Ce 75%/ La 25%) were synthesized by melting under controlled atmosphere and cast in plates. In these materials, rare earth metal are exclusively present in intermetallic phases homogeneously dispersed in the zinc matrix: Zn11Ce, Zn13La or Zn11Ce1-xLax and Zn13CeyLa1-y. The electrochemical behavior of these new alloys was investigated in a reference corrosivemedium. In parallel, the pure intermetallic phases Zn11Ce and Zn13La were synthesized and their electrochemical influence was studied by voltametry and galvanic coupling. Results show that both intermetallic phases act as preferential cathodic sites of dioxygen reduction and induce a cathodic inhibition of the corrosion of the Zn-RE alloys by comparison with pure zinc. This phenomenon is much more significant in the case of lanthanum containing alloys. In the specific case of cerium addition to zinc, an anodic inhibition was also observed and correlated with a chemical modification of the corrosion products (mainly made of hydrozincite). Actually, low quantities of cerium (less than 1 at.%) have been detected homogeneously in the corrosion layer by wave-length dispersive spectrometry. From results of controlled precipitation experiments of cerium and zinc salts performed in carbonated medium, the presence of cerium in the corrosionlayer and its protective character could be attributed to the formation of a mixed double lamellar zinc-cerium product. Therefore, addition to zinc of less than 2 wt.% of cerium or lanthanum allow to improve the corrosion resistance of zinc. However, by increasing the rare earth content in the alloys, the galvanic coupling phenomenon becomes more important and makes the alloys less resistant than pure zincMETZ-SCD (574632105) / SudocNANCY1-Bib. numérique (543959902) / SudocNANCY2-Bibliotheque electronique (543959901) / SudocNANCY-INPL-Bib. électronique (545479901) / SudocSudocFranceF

Chemotypes and radical scavenging activity of the essential oils from Artemisia arborescens L. growing in three areas of Bejaia (Algeria)

International audienceArtemisia arborescens L. is a medicinal and aromatic plant used in traditional medicine for its therapeutic properties to treat lung diseases, gastrointestinal disorders, diabetes and inflammations. The leaves of A. arborescens L. were harvested in Amizour, Cap Bouak and Sahel (Bejaia, Algeria) and their essential oils were analyzed by Gas Chromatography/Flame Ionization Detector and Gas Chromatography/Mass Spectrometry. The main constituents were β-thujone in the essential oil of Cap Bouak (59.8%), camphor in the volatile oil of Sahel (58.7%) and chamazulene in that of Amizour (31.4%). The radical scavenging activity of these essential oils was evaluated against DPPH and ABTS radicals by calculation of IC50. The best activity against DPPH and ABTS radicals were that of Sahel essential oil with IC50 DPPH = 133.0 µg/mL and IC50 ABTS = 211.6 µg/mL. The Spearman test revealed no significant correlations between IC50 DPPH and the chemical composition of the essential oil from A. arborescens L., while correlations with IC50 ABTS indicated that hydrocarbon monoterpenes, oxygenated monoterpenes and hydrocarbon sesquiterpenes promote activity against ABTS radical. These results can give prospects of using essential oils from A. arborescens L. as a natural adjunct in medicine formulations to treat diseases caused by oxidative stress

Correlation between chemical composition and antioxidant activity of the essential oils from leaves and berries of Schinus molle L. growing in two areas of Bejaia (Algeria)

International audienceSchinus molle L. is a medicinal and aromatic plant used in traditional medicine for his therapeutic properties. The leaves and berries of Schinus molle L. were collected in Iheddaden and Amriw (Bejaia, Algeria) and the essential oils were isolated by hydrodistillation with yields between 0.26 and 0.80%. The chemotype of the essential oils was sesquiterpene group, cadinene and cadinols subgroups. The cadinene subgroup was obtained from Iheddaden leaves and Amriw samples (leaves and berries) with proportions between 16.1 and 23.4%, while the cadinols subgroup was only shown with Iheddaden berries (30.5%). The antioxidant activities of the essential oils from leaves and berries of Schinus molle L. were low: IC50 DPPH were between 6.9 and 8.6 mg/mL, when IC50 ABTS varied between 0.7 and 5.0 mg/mL. Principal component analysis indicates that high proportions of oxygenated sesquiterpenes promote the antioxidant activity of essential oils from Schinus molle L. against ABTS radical, while the antioxidant activity against the DPPH radical requires the combination of the different chemical families contained in the essential oils of Schinus molle L

EMULSION LIQUID MEMBRANE EXTRACTION OF CERIUM IONS FROM ACIDIC SOLUTION USING CYANEX 301

Membrane processes for separation of chemical species from a mixture are gaining in importance and are emerging as a viable alternative to conventional separation processes. The emulsion liquid membrane (ELM) technique was regarded as an emerging separation technology and was extensively examined for potential applications in such fields as hydrometallurgy, environmental engineering, biochemical engineering, pharmaceutical engineering, and food technology. In the present work, the removal of Cerium ions from acidic solution by using an emulsion liquid membrane (ELM) technique was investigated and we obtained > 98% efficiency with the treatment. For the transport of Ce(III) ions using Cyanex 301 as extractant, the effects of extractant and surfactant concentrations, mixing speed, concentration and type of stripping solution, phase ratio, treatment ratio, and nature of diluent on the extraction rate were studies. Under the optimum conditions, solvent extraction and stripping of Ce(III) ions were investigated

New zinc-rare earth alloys: Influence of intermetallic compounds on the corrosion resistance

International audienceNew ZnRE 1-2 wt.% alloys (RE = Ce, La and Mischmetal) were synthesized. Microstructural analyses reveal that rare-earth metals are exclusively present in intermetallic phases contained within the zinc matrix: CeZn11 or LaZn13 in binary alloys; Ce1-xLaxZn11 and CeyLa1-yZn13 in Zn-Mischmetal alloys. This phase equilibrium is confirmed by a thermodynamic description of the Zn-rich corner of Zn-Ce-La system. Both intermetallic phases CeZn11 and LaZn13 induce a cathodic inhibition of the corrosion of the ZnRE alloys in comparison with pure zinc. In the specific case of cerium addition, a significant anodic inhibition is also observed