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Partager le résultat de cette recherche Interroger des sources externesCaractérisation et analyse des cellules solaires à base de silicium multicristallin / Zohra Benmohamed
Titre : Caractérisation et analyse des cellules solaires à base de silicium multicristallin Type de document : texte imprimé Auteurs : Zohra Benmohamed ; Univ. de Constantine, Éditeur scientifique ; Mohamed Remram, Directeur de thèse Année de publication : 2009 Importance : 95 f. Format : 30 cm Note générale : 01 Disponible à la salle de recherche 02 Disponibles au magazin de la B.U.C. 01 CD Langues : Français (fre) Catégories : Français - Anglais
ElectroniqueTags : Caractérisation Analyse Cellules solaires Silicium multicristallin Impurities Dislocations Multicrystalline silicon Solar cells Efficiency
الشوائب العيوب البنيوية السليسيوم متعدد البلوراتالخلايا الشمسية المردودIndex. décimale : 621 Electronique Résumé : An understanding of the comportment of defects and Impurities in multicrystalline silicon in turn leads
to a clearer picture of the limiting mechanisms in solar cells made with this promising material, and points to
possible paths for improvement. In this study a three diagnostic approach has been adopted for the
characterization of multicrystalline silicon samples, it comprises structural, chemical and electrical analysis of
the various minority diffusion length limiting defects and impurities which are responsible for the degradation of
the performances of multicrystalline silicon solar cells.
Preferential defect etching ions provided for the structural analysis. This approach was useful in
determining the nature and distribution of the structural defects. The work then focuses on chemical
characterization of impurities and the analytical tool used for this purpose were Fourier Transform Infra-red
Spectroscopy (FTIR). The results of annealing processes shown that, Rapid Thermal Annealing can dissociate
some oxygen precipitates existing in silicon material. This dissociation is accompanied by a degradation of the
bulk diffusion length. The effect of RTA on oxygen precipitation is extensively depending on the thermal history
of the material, the initial oxygen content and the existing precipitates in the material.
The above characterization tools were well complemented by electrical characterization through
Surface photovoltage (SPV) to determined minority diffusion length.
The results of PC1D modelling on multicrystalline silicon solar cells revealed that dislocations are not
the major factor that influences electrical properties of material. Impurities which were already present in the
grown material in an inactive form in particular the growth of oxygen precipitates and metallic impurities and
which have been electrically activated in an inhomogeneous distribution are also a principal source of
deterioration of polycrystalline silicon solar cells performances.
Thus there is a scope for attaining still higher efficiencies by further optimization of growth material
and cell processes to reduce reflection loss and effectively trapping the light inside the cell.Diplôme : Doctorat en sciences En ligne : ../theses/electronique/BEN5287.pdf Format de la ressource électronique : Permalink : index.php?lvl=notice_display&id=2774 Caractérisation et analyse des cellules solaires à base de silicium multicristallin [texte imprimé] / Zohra Benmohamed ; Univ. de Constantine, Éditeur scientifique ; Mohamed Remram, Directeur de thèse . - 2009 . - 95 f. ; 30 cm.
01 Disponible à la salle de recherche 02 Disponibles au magazin de la B.U.C. 01 CD
Langues : Français (fre)
Catégories : Français - Anglais
ElectroniqueTags : Caractérisation Analyse Cellules solaires Silicium multicristallin Impurities Dislocations Multicrystalline silicon Solar cells Efficiency
الشوائب العيوب البنيوية السليسيوم متعدد البلوراتالخلايا الشمسية المردودIndex. décimale : 621 Electronique Résumé : An understanding of the comportment of defects and Impurities in multicrystalline silicon in turn leads
to a clearer picture of the limiting mechanisms in solar cells made with this promising material, and points to
possible paths for improvement. In this study a three diagnostic approach has been adopted for the
characterization of multicrystalline silicon samples, it comprises structural, chemical and electrical analysis of
the various minority diffusion length limiting defects and impurities which are responsible for the degradation of
the performances of multicrystalline silicon solar cells.
Preferential defect etching ions provided for the structural analysis. This approach was useful in
determining the nature and distribution of the structural defects. The work then focuses on chemical
characterization of impurities and the analytical tool used for this purpose were Fourier Transform Infra-red
Spectroscopy (FTIR). The results of annealing processes shown that, Rapid Thermal Annealing can dissociate
some oxygen precipitates existing in silicon material. This dissociation is accompanied by a degradation of the
bulk diffusion length. The effect of RTA on oxygen precipitation is extensively depending on the thermal history
of the material, the initial oxygen content and the existing precipitates in the material.
The above characterization tools were well complemented by electrical characterization through
Surface photovoltage (SPV) to determined minority diffusion length.
The results of PC1D modelling on multicrystalline silicon solar cells revealed that dislocations are not
the major factor that influences electrical properties of material. Impurities which were already present in the
grown material in an inactive form in particular the growth of oxygen precipitates and metallic impurities and
which have been electrically activated in an inhomogeneous distribution are also a principal source of
deterioration of polycrystalline silicon solar cells performances.
Thus there is a scope for attaining still higher efficiencies by further optimization of growth material
and cell processes to reduce reflection loss and effectively trapping the light inside the cell.Diplôme : Doctorat en sciences En ligne : ../theses/electronique/BEN5287.pdf Format de la ressource électronique : Permalink : index.php?lvl=notice_display&id=2774 Exemplaires (1)
Code-barres Cote Support Localisation Section Disponibilité BEN/5287 BEN/5287 Thèse Bibliothèque principale Thèses Disponible
Titre : Caractérisation des bactéries isolées à partir du genre Trigonella L. (Légumineuses) possant dans différents écosystèmes de l'Est algérien Type de document : texte imprimé Auteurs : Rabah Chabbi, Auteur ; Univ. de Constantine, Éditeur scientifique ; Yacine Benhizia, Directeur de thèse Année de publication : 2009 Importance : 103 f. Note générale : 01 Disponible à la salle de recherche 01 Disponible au magazin de la B.U.C. 01 CD Langues : Français (fre) Catégories : Français - Anglais
BiologieTags : Caractérisation Rhizobium Gammaproteobacteria Symbiote Trrigonella Characterization Symbiots Trogonella L وصف متعايش Index. décimale : 570 Sciences de la vie. Biologie Résumé : This work has been realized in order to evaluation and caracterisation of the
phenotypical diversity that exists within a collection of symbiots isolated from nodosities of
three Fenugreek populations originated form different regions of east Algeria.
The SDS page has revealed a great level of proteic polymorphism between the isolates. This
technique has allowed us to highlight the possible multiple infection among Trigonella L.
All the strains are infective towards Trigonella L with a relative efficiency that is
reflected by a good growing level of the obtained feet.
The fast growth of the strains and the assimilation of the charred substratum have
revealed profiles that are comparable to those of Rhizobium. In contrast, the strains have
manifested, like the Gammaproteobacteria, a great resistance to heavy metals and antibiotics.
A great tolerance to NaCl, pH, and temperature variation has been noticed for the whole
collection.
We have defined, on the base of the Azote fixative potential and the tolerance of
alkalinity, candidates that are efficient enough to be used for inoculation in the field.Diplôme : Magistère En ligne : ../theses/biologie/CHA5602.pdf Permalink : index.php?lvl=notice_display&id=1817 Caractérisation des bactéries isolées à partir du genre Trigonella L. (Légumineuses) possant dans différents écosystèmes de l'Est algérien [texte imprimé] / Rabah Chabbi, Auteur ; Univ. de Constantine, Éditeur scientifique ; Yacine Benhizia, Directeur de thèse . - 2009 . - 103 f.
01 Disponible à la salle de recherche 01 Disponible au magazin de la B.U.C. 01 CD
Langues : Français (fre)
Catégories : Français - Anglais
BiologieTags : Caractérisation Rhizobium Gammaproteobacteria Symbiote Trrigonella Characterization Symbiots Trogonella L وصف متعايش Index. décimale : 570 Sciences de la vie. Biologie Résumé : This work has been realized in order to evaluation and caracterisation of the
phenotypical diversity that exists within a collection of symbiots isolated from nodosities of
three Fenugreek populations originated form different regions of east Algeria.
The SDS page has revealed a great level of proteic polymorphism between the isolates. This
technique has allowed us to highlight the possible multiple infection among Trigonella L.
All the strains are infective towards Trigonella L with a relative efficiency that is
reflected by a good growing level of the obtained feet.
The fast growth of the strains and the assimilation of the charred substratum have
revealed profiles that are comparable to those of Rhizobium. In contrast, the strains have
manifested, like the Gammaproteobacteria, a great resistance to heavy metals and antibiotics.
A great tolerance to NaCl, pH, and temperature variation has been noticed for the whole
collection.
We have defined, on the base of the Azote fixative potential and the tolerance of
alkalinity, candidates that are efficient enough to be used for inoculation in the field.Diplôme : Magistère En ligne : ../theses/biologie/CHA5602.pdf Permalink : index.php?lvl=notice_display&id=1817 Exemplaires (1)
Code-barres Cote Support Localisation Section Disponibilité CHA/5602 CHA/5602 Thèse Bibliothèque principale Thèses Disponible
Titre : Caractérisation de l'huile d'olive algérienne : apport des méthodes chimiothérapiques. Type de document : texte imprimé Auteurs : Hamida Benabid, Auteur ; Hacène Namoune, Directeur de thèse ; Douglas N. Rutledge, Directeur de thèse Editeur : Constantine : Université Mentouri Constantine Année de publication : 2009 Importance : 165 f. Note générale : 01 Disponible à la salle de recherche 02 Disponibles au magazin de la B.U.C. 01 CD Langues : Français (fre) Catégories : Français - Anglais
Nutrition, Alimentation et Technologies Agro-AlimentairesTags : Sciences Alimentaires Caractérisation Fluorescence Huile d'olive Régions Chimiométrie Olive oil Characterization Areas Chemometrics زيت الزيتون المناطق مصفوفات مضان كيميومتري Index. décimale : 640 Industrie Alimentaire Résumé : Olive oil is one of the oldest vegetable oils and the only one that can be consumed in its raw form without prior treatment. The well-known health benefits of olive oil are linked to its fatty acid composition in which oleic acid is the main component, and the presence of minor biomolecules, such as vitamins and natural antioxidants.
The strong demand for quality virgin olive oil is not only due to its health virtues, but also to its organoleptic properties.
In Algeria, plantations are characterized by great diversity and for the most part, by a traditional olive orchard. The consumption of oil maâsras is today a basic diet in many rural areas of the country. In these regions, oils are considered to be of good quality. The present study on olive oil produced in several olive growing regions of Algeria has the dual purpose of studying the chemical parameters and fatty acid composition by conventional analytical methods, and of characterizing these oils by spectral methods, including 3D- fluorescence spectroscopy.
Different chemometric methods: Principal Component Analysis (PCA), Canonical Discriminant Analysis (CDA), Independent Component Analysis (ICA), and PARAFAC (PARAllel FACtor analysis) are used to treat the data.
The first results indicate that the chemical composition of olive oils from different regions of Algeria is quite variable.
The Principal Component Analysis (PCA) was used for an initial exploratory analysis of the data. The first three latent variables explain 64.1% of the total variance of the samples from the five regions. Then, a Canonical Discriminant Analysis (CDA) showed that the most discriminant variables are K270 and Delta K for oil samples from the region of Constantine, the peroxide and γ-tocopherol for samples from the regions of Tizi Ouzou and Sétif, respectively.
The variations due to the presence of Rayleigh and Raman scattering in excitation– emission fluorescence matrices, distort the PARAFAC model.
A solution to eliminate the artefacts interfering with the relevant information was achieved by applying Independent Component Analysis to the row-wise unfolded array. A PARAFAC model was then built on the refolded array, reconstructed without the independent component(s) related to the “artefact signals”. The PARAFAC components obtained were interpreted by relating them to some compounds present in the analysed samples. The results of multivariate analyses show that the chemical parameters of olive oils contain enough information to distinguish the production areas of studied Algerian oil.Note de contenu : Annexes. Diplôme : Doctorat en sciences En ligne : ../theses/agronomie/BEN5330.pdf Format de la ressource électronique : Permalink : index.php?lvl=notice_display&id=4438 Caractérisation de l'huile d'olive algérienne : apport des méthodes chimiothérapiques. [texte imprimé] / Hamida Benabid, Auteur ; Hacène Namoune, Directeur de thèse ; Douglas N. Rutledge, Directeur de thèse . - Constantine : Université Mentouri Constantine, 2009 . - 165 f.
01 Disponible à la salle de recherche 02 Disponibles au magazin de la B.U.C. 01 CD
Langues : Français (fre)
Catégories : Français - Anglais
Nutrition, Alimentation et Technologies Agro-AlimentairesTags : Sciences Alimentaires Caractérisation Fluorescence Huile d'olive Régions Chimiométrie Olive oil Characterization Areas Chemometrics زيت الزيتون المناطق مصفوفات مضان كيميومتري Index. décimale : 640 Industrie Alimentaire Résumé : Olive oil is one of the oldest vegetable oils and the only one that can be consumed in its raw form without prior treatment. The well-known health benefits of olive oil are linked to its fatty acid composition in which oleic acid is the main component, and the presence of minor biomolecules, such as vitamins and natural antioxidants.
The strong demand for quality virgin olive oil is not only due to its health virtues, but also to its organoleptic properties.
In Algeria, plantations are characterized by great diversity and for the most part, by a traditional olive orchard. The consumption of oil maâsras is today a basic diet in many rural areas of the country. In these regions, oils are considered to be of good quality. The present study on olive oil produced in several olive growing regions of Algeria has the dual purpose of studying the chemical parameters and fatty acid composition by conventional analytical methods, and of characterizing these oils by spectral methods, including 3D- fluorescence spectroscopy.
Different chemometric methods: Principal Component Analysis (PCA), Canonical Discriminant Analysis (CDA), Independent Component Analysis (ICA), and PARAFAC (PARAllel FACtor analysis) are used to treat the data.
The first results indicate that the chemical composition of olive oils from different regions of Algeria is quite variable.
The Principal Component Analysis (PCA) was used for an initial exploratory analysis of the data. The first three latent variables explain 64.1% of the total variance of the samples from the five regions. Then, a Canonical Discriminant Analysis (CDA) showed that the most discriminant variables are K270 and Delta K for oil samples from the region of Constantine, the peroxide and γ-tocopherol for samples from the regions of Tizi Ouzou and Sétif, respectively.
The variations due to the presence of Rayleigh and Raman scattering in excitation– emission fluorescence matrices, distort the PARAFAC model.
A solution to eliminate the artefacts interfering with the relevant information was achieved by applying Independent Component Analysis to the row-wise unfolded array. A PARAFAC model was then built on the refolded array, reconstructed without the independent component(s) related to the “artefact signals”. The PARAFAC components obtained were interpreted by relating them to some compounds present in the analysed samples. The results of multivariate analyses show that the chemical parameters of olive oils contain enough information to distinguish the production areas of studied Algerian oil.Note de contenu : Annexes. Diplôme : Doctorat en sciences En ligne : ../theses/agronomie/BEN5330.pdf Format de la ressource électronique : Permalink : index.php?lvl=notice_display&id=4438 Exemplaires (1)
Code-barres Cote Support Localisation Section Disponibilité BEN/5330 BEN/5330 Thèse Bibliothèque principale Thèses Disponible
Titre : Caractérisation de quelques variétés de vigne autochtones (Vitis Vinifera L.) Type de document : texte imprimé Auteurs : Univ. de Constantine, Éditeur scientifique Année de publication : 2004 Importance : 77 f. Note générale : 01 Disponible à la salle de recherche
02 Disponibles au magasin de la bibliothèque centraleLangues : Français (fre) Catégories : Français - Anglais
BiologieTags : Rendement Caractérisation Croissance Cépage Vigueur Nouaison Autochtone Ampélographie Reconstruction feuille moyenne Index. décimale : 570 Sciences de la vie. Biologie Permalink : index.php?lvl=notice_display&id=1527 Caractérisation de quelques variétés de vigne autochtones (Vitis Vinifera L.) [texte imprimé] / Univ. de Constantine, Éditeur scientifique . - 2004 . - 77 f.
01 Disponible à la salle de recherche
02 Disponibles au magasin de la bibliothèque centrale
Langues : Français (fre)
Catégories : Français - Anglais
BiologieTags : Rendement Caractérisation Croissance Cépage Vigueur Nouaison Autochtone Ampélographie Reconstruction feuille moyenne Index. décimale : 570 Sciences de la vie. Biologie Permalink : index.php?lvl=notice_display&id=1527 Exemplaires (1)
Code-barres Cote Support Localisation Section Disponibilité LAI/4028 LAI/4028 Thèse Bibliothèque principale Thèses Disponible
Titre : Elaboration et caractérisation du diseleniures de niobium NbSe2 et du materiau hybride PANi-NbSe2 Type de document : texte imprimé Auteurs : Noureddine Kerai ; Univ. de Constantine, Éditeur scientifique ; Z. Ouili, Directeur de thèse Année de publication : 2007 Importance : 77 f. Note générale : 01 Disponible à la salle de recherche 02 Disponibles au magazin de la B.U.C. 01 CD Langues : Français (fre) Catégories : Français - Anglais
PhysiqueTags : Caractérisation Polymère MEB Dichalcogenides MX2 NbSe2 Elaboration Dicvol 04 Index. décimale : 530 Physique En ligne : ../theses/physique/KER4906.pdf Permalink : index.php?lvl=notice_display&id=3512 Elaboration et caractérisation du diseleniures de niobium NbSe2 et du materiau hybride PANi-NbSe2 [texte imprimé] / Noureddine Kerai ; Univ. de Constantine, Éditeur scientifique ; Z. Ouili, Directeur de thèse . - 2007 . - 77 f.
01 Disponible à la salle de recherche 02 Disponibles au magazin de la B.U.C. 01 CD
Langues : Français (fre)
Catégories : Français - Anglais
PhysiqueTags : Caractérisation Polymère MEB Dichalcogenides MX2 NbSe2 Elaboration Dicvol 04 Index. décimale : 530 Physique En ligne : ../theses/physique/KER4906.pdf Permalink : index.php?lvl=notice_display&id=3512 Exemplaires (1)
Code-barres Cote Support Localisation Section Disponibilité KER/4906 KER/4906 Thèse Bibliothèque principale Thèses Disponible Permalink
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