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Partager le résultat de cette recherche Interroger des sources externesExtraction et analyse des éléments majeurs et traces contenus dans les poussières prélevées dans l’air ambiant à Constantine / Amina Kemmouche ép Ghallab
Titre : Extraction et analyse des éléments majeurs et traces contenus dans les poussières prélevées dans l’air ambiant à Constantine Type de document : texte imprimé Auteurs : Amina Kemmouche ép Ghallab, Auteur ; Hocine Ali Khodja, Directeur de thèse Editeur : جامعة الإخوة منتوري قسنطينة Année de publication : 2018 Importance : 127 f. Format : 30 cm. Note générale : 2 copies imprimées disponibles. Langues : Français (fre) Catégories : Français - Anglais
ChimieTags : PM10 extraction totale extraction partielle éléments métalliques méthode de digestion EN-14902 bulk extraction partial extraction metallic elements digestion method EN-14902 14902??????? ????????? ???????? PM10????????? ????? ????????? ?????? ??????? ???????? Index. décimale : 540 Chimie et sciences connexes Résumé : When high mineral loads in atmospheric particulate matter (PM) are present, particular attention should be paid to the selection of appropriate acidic digestion protocols for wet chemical analysis. We report on a comparative study of elemental recovery yields from five different pre-analytical acid digestion procedures for mineral-rich urban background PM10 samples collected in the city of Constantine (Northeastern Algeria). Five reference materials (NIST 1633b, UPM 1648, NAT-7, SO-2 and SO-4) were also digested according to the same protocols. The selected acidic digestion procedures are widely used for PM chemical analysis,
and comprise: P1 (HNO3/HF/HCl), P2 (HCl/HNO3), P3 (HCl/H2O2/HNO3), P4 (HNO3/HF/HClO4) and P5 (HNO3/H2O2); the latter is assisted with micro-wave digestion.
Elemental recovery yields were compared for major and trace elements typically determined in PM for source apportionment analysis and the results evidenced large differences. For most elements, the bulk extraction procedures (requiring the use of HF) allowed a full elemental recovery, particularly for elements that are associated with aluminum-silicate species and oxides that are resistant to mild acid attack. In contrast, in the extraction protocols without HF, low recovery yields were obtained for elements such as Al, Ti, Zr, Sc, and other aluminumsilicate-related elements in PM10 samples with high mineral dust load. We highlight
that the European standard digestion method EN-14902: 2005 should be applied specifically for the metals for which this method was developed, but caution should be taken when the analysis of other elements in PM is required, especially in urban areas where road and vehicle wear dust is likely to be a major component of ambient PM. When using wet chemistry analysis for PM source apportionment studies, we strongly recommend HF bulk dissolution of samples to ensure the reliability of the geochemical information when coupled with an appropriate analytical tool.
Diplôme : Doctorat En ligne : ../theses/chimie/KEM7203.pdf Format de la ressource électronique : Permalink : https://bu.umc.edu.dz/md/index.php?lvl=notice_display&id=10760 Extraction et analyse des éléments majeurs et traces contenus dans les poussières prélevées dans l’air ambiant à Constantine [texte imprimé] / Amina Kemmouche ép Ghallab, Auteur ; Hocine Ali Khodja, Directeur de thèse . - [S.l.] : جامعة الإخوة منتوري قسنطينة, 2018 . - 127 f. ; 30 cm.
2 copies imprimées disponibles.
Langues : Français (fre)
Catégories : Français - Anglais
ChimieTags : PM10 extraction totale extraction partielle éléments métalliques méthode de digestion EN-14902 bulk extraction partial extraction metallic elements digestion method EN-14902 14902??????? ????????? ???????? PM10????????? ????? ????????? ?????? ??????? ???????? Index. décimale : 540 Chimie et sciences connexes Résumé : When high mineral loads in atmospheric particulate matter (PM) are present, particular attention should be paid to the selection of appropriate acidic digestion protocols for wet chemical analysis. We report on a comparative study of elemental recovery yields from five different pre-analytical acid digestion procedures for mineral-rich urban background PM10 samples collected in the city of Constantine (Northeastern Algeria). Five reference materials (NIST 1633b, UPM 1648, NAT-7, SO-2 and SO-4) were also digested according to the same protocols. The selected acidic digestion procedures are widely used for PM chemical analysis,
and comprise: P1 (HNO3/HF/HCl), P2 (HCl/HNO3), P3 (HCl/H2O2/HNO3), P4 (HNO3/HF/HClO4) and P5 (HNO3/H2O2); the latter is assisted with micro-wave digestion.
Elemental recovery yields were compared for major and trace elements typically determined in PM for source apportionment analysis and the results evidenced large differences. For most elements, the bulk extraction procedures (requiring the use of HF) allowed a full elemental recovery, particularly for elements that are associated with aluminum-silicate species and oxides that are resistant to mild acid attack. In contrast, in the extraction protocols without HF, low recovery yields were obtained for elements such as Al, Ti, Zr, Sc, and other aluminumsilicate-related elements in PM10 samples with high mineral dust load. We highlight
that the European standard digestion method EN-14902: 2005 should be applied specifically for the metals for which this method was developed, but caution should be taken when the analysis of other elements in PM is required, especially in urban areas where road and vehicle wear dust is likely to be a major component of ambient PM. When using wet chemistry analysis for PM source apportionment studies, we strongly recommend HF bulk dissolution of samples to ensure the reliability of the geochemical information when coupled with an appropriate analytical tool.
Diplôme : Doctorat En ligne : ../theses/chimie/KEM7203.pdf Format de la ressource électronique : Permalink : https://bu.umc.edu.dz/md/index.php?lvl=notice_display&id=10760 Exemplaires (1)
Code-barres Cote Support Localisation Section Disponibilité KEM/7203 KEM/7203 Thèse Bibliothèque principale Thèses Disponible
Titre : Contribution à l'étude de l'action d'agents polluants sur des végétaux bioindicateurs Type de document : texte imprimé Auteurs : Saida Zaimeche, Auteur ; Chaabane Rahmoune, Directeur de thèse Editeur : جامعة الإخوة منتوري قسنطينة Année de publication : 2015 Importance : 173 f. Format : 30 cm. Note générale : 2 copies imprimes disponibles Langues : Français (fre) Catégories : Français - Anglais
BiologieTags : Ecotoxicologie pollution des écosystèmes Metallic elements Bioaccumulation Chlorella sp. Lemna minor Phragmites communis Typha latifolia Physiologic and BioChimical parameters ??????? ??????? ??????????? ? ???????????? Index. décimale : 570 Sciences de la vie. Biologie Résumé : The aim of this study could put in evidence the parameters determined the
contamination of water course of the locality of Oued Athmenia with elements traces
metallic and evaluated their potential effects on aquatic vegetable species.
Four aquatic species; unicellular alga Chlorella sp. and macrophytes floating as well as
emergent plants (Lemna minor, phragmites communis and Typha latifolia) were
examined for their bioaccumulation of metallic elements.
Beside this multitude of pollutants rejected in the environment, this species could or not
adapted and therefore responded to the presence of these contaminants? Specially, that
these contaminants can enter in competition with some ions necessary for their essential
metabolites and replaced them at the active sites of several enzymes, which could cause
decreased performance energetic, significant disturbance in their physiological and
biochemical functioning.
In the other hand, during this experimentation, the duck weed Lemna minor was more
sensitive to the environment stress by the decline of their biomass, especially in the
stations localized downstream.
Chlorella sp. first link of the food chain, without root can be preserved of the influence
of the substratum can reflected the quality of water course.
Phragmites communis and Typha latifolia were demonstrated their capacity to
accumulate high contents of these elements, but apparition of morphological (visual)
symptoms of clorosis on above ground part.
Finally, these species take into consideration in this study could give overall assessment
of the quality of these water courses and the bioaccumulation of these elements in their
organisms was an index of pollution. Beside this, these species were demonstrated their
capacity to accumulate and to remove pollutants from this aquatic environment it’s very
important to preserve this aquatic flora, seeing their function in this environment.Diplôme : Doctorat en sciences En ligne : ../theses/biologie/ZAI6847.pdf Format de la ressource électronique : Permalink : https://bu.umc.edu.dz/md/index.php?lvl=notice_display&id=10144 Contribution à l'étude de l'action d'agents polluants sur des végétaux bioindicateurs [texte imprimé] / Saida Zaimeche, Auteur ; Chaabane Rahmoune, Directeur de thèse . - [S.l.] : جامعة الإخوة منتوري قسنطينة, 2015 . - 173 f. ; 30 cm.
2 copies imprimes disponibles
Langues : Français (fre)
Catégories : Français - Anglais
BiologieTags : Ecotoxicologie pollution des écosystèmes Metallic elements Bioaccumulation Chlorella sp. Lemna minor Phragmites communis Typha latifolia Physiologic and BioChimical parameters ??????? ??????? ??????????? ? ???????????? Index. décimale : 570 Sciences de la vie. Biologie Résumé : The aim of this study could put in evidence the parameters determined the
contamination of water course of the locality of Oued Athmenia with elements traces
metallic and evaluated their potential effects on aquatic vegetable species.
Four aquatic species; unicellular alga Chlorella sp. and macrophytes floating as well as
emergent plants (Lemna minor, phragmites communis and Typha latifolia) were
examined for their bioaccumulation of metallic elements.
Beside this multitude of pollutants rejected in the environment, this species could or not
adapted and therefore responded to the presence of these contaminants? Specially, that
these contaminants can enter in competition with some ions necessary for their essential
metabolites and replaced them at the active sites of several enzymes, which could cause
decreased performance energetic, significant disturbance in their physiological and
biochemical functioning.
In the other hand, during this experimentation, the duck weed Lemna minor was more
sensitive to the environment stress by the decline of their biomass, especially in the
stations localized downstream.
Chlorella sp. first link of the food chain, without root can be preserved of the influence
of the substratum can reflected the quality of water course.
Phragmites communis and Typha latifolia were demonstrated their capacity to
accumulate high contents of these elements, but apparition of morphological (visual)
symptoms of clorosis on above ground part.
Finally, these species take into consideration in this study could give overall assessment
of the quality of these water courses and the bioaccumulation of these elements in their
organisms was an index of pollution. Beside this, these species were demonstrated their
capacity to accumulate and to remove pollutants from this aquatic environment it’s very
important to preserve this aquatic flora, seeing their function in this environment.Diplôme : Doctorat en sciences En ligne : ../theses/biologie/ZAI6847.pdf Format de la ressource électronique : Permalink : https://bu.umc.edu.dz/md/index.php?lvl=notice_display&id=10144 Exemplaires (1)
Code-barres Cote Support Localisation Section Disponibilité ZAI/6847 ZAI/6847 Thèse Bibliothèque principale Thèses Disponible
