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Partager le résultat de cette recherche Interroger des sources externesElaboration des nanocomposites ZnSe/SILICE , ZnO/SILICE , ZnSe/POLYSTYRENE et ZnO/POLYSTYRENE.Caractérisation structurale et optique / Azeddine Chelouche
Titre : Elaboration des nanocomposites ZnSe/SILICE , ZnO/SILICE , ZnSe/POLYSTYRENE et ZnO/POLYSTYRENE.Caractérisation structurale et optique Type de document : texte imprimé Auteurs : Azeddine Chelouche ; Université Mentouri, Editeur scientifique ; M. Sebais, Directeur de thèse Année de publication : 2007 Importance : 104 f. Note générale : 01 Disponible à la salle de recherche 02 Disponibles au magazin de la B.U.C. 01 CD Langues : Français (fre) Tags : Silice DRX ZnO Absorption optique Sol-gel Polystyrène Nanocomposites ZnSe Micro-Raman FT-IR Photoluminisescence Index. décimale : 530 Physique En ligne : ../theses/physique/CHE4903.pdf Permalink : https://bu.umc.edu.dz/md/index.php?lvl=notice_display&id=3518 Elaboration des nanocomposites ZnSe/SILICE , ZnO/SILICE , ZnSe/POLYSTYRENE et ZnO/POLYSTYRENE.Caractérisation structurale et optique [texte imprimé] / Azeddine Chelouche ; Université Mentouri, Editeur scientifique ; M. Sebais, Directeur de thèse . - 2007 . - 104 f.
01 Disponible à la salle de recherche 02 Disponibles au magazin de la B.U.C. 01 CD
Langues : Français (fre)
Tags : Silice DRX ZnO Absorption optique Sol-gel Polystyrène Nanocomposites ZnSe Micro-Raman FT-IR Photoluminisescence Index. décimale : 530 Physique En ligne : ../theses/physique/CHE4903.pdf Permalink : https://bu.umc.edu.dz/md/index.php?lvl=notice_display&id=3518 Exemplaires
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Titre : Synthèse et caractérisation des nanocomposites polypropylène argile Type de document : texte imprimé Auteurs : Fatima Zohra Benlahreche ; Université Mentouri, Editeur scientifique ; S. Bensaad, Directeur de thèse Année de publication : 2002 Importance : 105 f. Note générale : 1 Disponible à la salle de recherche
2 Disponibles au magasin de la bibliothèque centraleLangues : Français (fre) Tags : Nanocomposites Polypropylène argile Index. décimale : 661 Chimie Industrielle Permalink : https://bu.umc.edu.dz/md/index.php?lvl=notice_display&id=4516 Synthèse et caractérisation des nanocomposites polypropylène argile [texte imprimé] / Fatima Zohra Benlahreche ; Université Mentouri, Editeur scientifique ; S. Bensaad, Directeur de thèse . - 2002 . - 105 f.
1 Disponible à la salle de recherche
2 Disponibles au magasin de la bibliothèque centrale
Langues : Français (fre)
Tags : Nanocomposites Polypropylène argile Index. décimale : 661 Chimie Industrielle Permalink : https://bu.umc.edu.dz/md/index.php?lvl=notice_display&id=4516 Exemplaires
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Titre : Etude des proprietes structurales et optiques des nanocomposites Ag/SiO2 Type de document : texte imprimé Auteurs : Zakaria Nouicer, Auteur ; N. Keghouche, Directeur de thèse Editeur : Constantine : Université Mentouri Constantine Année de publication : 2015 Importance : 77 f. Format : 30 cm. Note générale : 2 copies imprimées disponibles
Langues : Français (fre) Tags : Nanocomposites Argent Silice SiO2 Silver Silica SiO2 Ag/SiO2 ?????????? ??? ????? SiO2 ????? ????????? ??? ??????? SiO2/Ag Index. décimale : 530 Physique Résumé : In this work, composite silver / silica were studied. In a first step, the Ag+ ions of various compositions (2.5, 5, 7.5 and 10%) were fixed on the silica by ion exchange. In a second step, the samples were annealed in air at temperatures ranging from 100 to 700° C. Several experimental techniques (SEM, XRD, FTIR, UV-Visible) were used to characterize the samples at various stages of development.
The X-ray diffraction has identified several phases formed (Ag2Si2O5; Ag2SiO3 ; Ag3Si and Ag) for the respective proportions: 2.5; 5; 7.5 and 10% of Ag+ ions/SiO2.
After heat treatment, for a charge of 5%, the X-ray diffraction revealed the formation of silver silicates (Ag4SiO4; Ag6Si2O7; Ag10Si4O13) for temperatures below 500°C and Ag phase to higher temperatures (600 and 700°C).
FTIR spectra of the samples Ag/SiO2 present five bands in the region 400 to 2000 cm-1 assigned to the vibration: Si-O-Si, Ag-W, Ag-SO4, Si-O and Si-OH. The spectrum of the sample content of 2.5% Ag+ has well-resolved peaks. The increase of the Ag+ ions load causes an overlap of peaks relating to the groups: Si-O and Si-OH.
An FTIR spectrum of displacement toward the low wave numbers was observed after annealing at 200° C. For larger annealing temperatures (300 to 700° C), the spectrum is moved in the opposite direction. This correlates with the formation of large silver nanoparticles.
The UV-visible absorption spectrum of nanocomposites Ag/SiO2 has a wide band in the UV region (300 to 370 nm) for the different ion contents Ag+/SiO2. This absorption is attributed to the surface plasmon resonance. Following the heat treatment, a shift of this band to the blue is observed
Diplôme : Magistère En ligne : ../theses/physique/NOU6767.pdf Format de la ressource électronique : Permalink : https://bu.umc.edu.dz/md/index.php?lvl=notice_display&id=9846 Etude des proprietes structurales et optiques des nanocomposites Ag/SiO2 [texte imprimé] / Zakaria Nouicer, Auteur ; N. Keghouche, Directeur de thèse . - Constantine : Université Mentouri Constantine, 2015 . - 77 f. ; 30 cm.
2 copies imprimées disponibles
Langues : Français (fre)
Tags : Nanocomposites Argent Silice SiO2 Silver Silica SiO2 Ag/SiO2 ?????????? ??? ????? SiO2 ????? ????????? ??? ??????? SiO2/Ag Index. décimale : 530 Physique Résumé : In this work, composite silver / silica were studied. In a first step, the Ag+ ions of various compositions (2.5, 5, 7.5 and 10%) were fixed on the silica by ion exchange. In a second step, the samples were annealed in air at temperatures ranging from 100 to 700° C. Several experimental techniques (SEM, XRD, FTIR, UV-Visible) were used to characterize the samples at various stages of development.
The X-ray diffraction has identified several phases formed (Ag2Si2O5; Ag2SiO3 ; Ag3Si and Ag) for the respective proportions: 2.5; 5; 7.5 and 10% of Ag+ ions/SiO2.
After heat treatment, for a charge of 5%, the X-ray diffraction revealed the formation of silver silicates (Ag4SiO4; Ag6Si2O7; Ag10Si4O13) for temperatures below 500°C and Ag phase to higher temperatures (600 and 700°C).
FTIR spectra of the samples Ag/SiO2 present five bands in the region 400 to 2000 cm-1 assigned to the vibration: Si-O-Si, Ag-W, Ag-SO4, Si-O and Si-OH. The spectrum of the sample content of 2.5% Ag+ has well-resolved peaks. The increase of the Ag+ ions load causes an overlap of peaks relating to the groups: Si-O and Si-OH.
An FTIR spectrum of displacement toward the low wave numbers was observed after annealing at 200° C. For larger annealing temperatures (300 to 700° C), the spectrum is moved in the opposite direction. This correlates with the formation of large silver nanoparticles.
The UV-visible absorption spectrum of nanocomposites Ag/SiO2 has a wide band in the UV region (300 to 370 nm) for the different ion contents Ag+/SiO2. This absorption is attributed to the surface plasmon resonance. Following the heat treatment, a shift of this band to the blue is observed
Diplôme : Magistère En ligne : ../theses/physique/NOU6767.pdf Format de la ressource électronique : Permalink : https://bu.umc.edu.dz/md/index.php?lvl=notice_display&id=9846 Exemplaires
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Titre : Elaboration et caractérisation de nanocomposites hybrides : Oxydes métalliques/polymères Type de document : texte imprimé Auteurs : Bariza Troudi, Auteur ; Ouahiba Halimi, Directeur de thèse Editeur : جامعة الإخوة منتوري قسنطينة Année de publication : 2017 Importance : 121 f. Format : 30 cm. Note générale : 2 copies imprimées disponibles
Langues : Français (fre) Tags : Synthèse hydrothermale Nanocomposites Films minces CuO/PS CuO/PVC PbO/PS PbO/PVC DRX FT-IR Raman AFM Absorption UV-Visible photoluminescence Hydrothermal synthesis thin films UV-Visible Absorption ?????? ?????? ????? ????? ???????? ??? ????????- ???? ???????? ?????? Index. décimale : 530 Physique Résumé : Thin films of metal oxides/polymers nanocomposites were deposited on glass substrates by Spin-Coating and Dip-Coating techniques. The nanocomposites were elaborated by inserting, in the matrices of polystyrene (PS) and polyvinyl chloride (PVC) polymers, of nanoparticles of metal oxides such as copper oxide (CuO) and lead oxide (PbO). The nanoparticles of semiconductor CuO and PbO were synthesized beforehand by the hydrothermal method. The xray diffraction characterization of the obtained powders have revealed a monoclinic phase for CuO crystallites and an orthorhombic phase for PbO. The size of the crystallites of the two semiconductors is of a nanometic order. Calcul the of gap energy indicate a shift towards high energies compared to massive crystals. This shift is due to the effect of the quantum confinement induced by the nanometric size of the crystallites of the semiconductors. These nanocrystals are used for the preparation of the nanocomposites of CuO/PS, CuO/PVC, PbO/PS and PbO/PVC by
simple insertion of CuO and PbO nanoparticles in the PS and PVC polymers. The analysis of the elaborated nanocomposites by X-ray diffraction has allowed to notice the incorporation of the CuO and PbO crystallites into the PS and PVC polymers matrixes and analysis by Raman and infrared spectroscopies has confirmed the presence of CuO and PbO crystallites in the PS and PVC matrixes by revealing specific vibration modes to the Cu-O and Pb-O bonds. The surface morphology and topography of thin films of nanocomposites were highlighted with the help of atomic force microscopy (AFM) and have shown homogeneous dispersion of CuO and PbO crystallites and a low surface roughness. the characterization by measurement of the optical absorption in the UV-Visible domain allows to observe the increase in optical absorption which is attributed to CuO and PbO nanocrystallites because PS and PVC are optically transparent in the UV-Visible domain. A shift of the gap energy of the nanocomposites compared with the gap energy of the pure polymers and the massive crystallites of CuO and PbO was observed. This variation in gap energy is the result of the new optical behavior of the prepared nanocomposites.
The optical characterization by the measure of the photoluminescence has shown that the elaborated samples present intense luminescence bands in the visible range, hence the possibility of consider these matrices as optically active media and can be used for the making devices of specific optics properties.
Diplôme : Doctorat en sciences En ligne : ../theses/physique/TRO7142.pdf Format de la ressource électronique : Permalink : https://bu.umc.edu.dz/md/index.php?lvl=notice_display&id=10460 Elaboration et caractérisation de nanocomposites hybrides : Oxydes métalliques/polymères [texte imprimé] / Bariza Troudi, Auteur ; Ouahiba Halimi, Directeur de thèse . - [S.l.] : جامعة الإخوة منتوري قسنطينة, 2017 . - 121 f. ; 30 cm.
2 copies imprimées disponibles
Langues : Français (fre)
Tags : Synthèse hydrothermale Nanocomposites Films minces CuO/PS CuO/PVC PbO/PS PbO/PVC DRX FT-IR Raman AFM Absorption UV-Visible photoluminescence Hydrothermal synthesis thin films UV-Visible Absorption ?????? ?????? ????? ????? ???????? ??? ????????- ???? ???????? ?????? Index. décimale : 530 Physique Résumé : Thin films of metal oxides/polymers nanocomposites were deposited on glass substrates by Spin-Coating and Dip-Coating techniques. The nanocomposites were elaborated by inserting, in the matrices of polystyrene (PS) and polyvinyl chloride (PVC) polymers, of nanoparticles of metal oxides such as copper oxide (CuO) and lead oxide (PbO). The nanoparticles of semiconductor CuO and PbO were synthesized beforehand by the hydrothermal method. The xray diffraction characterization of the obtained powders have revealed a monoclinic phase for CuO crystallites and an orthorhombic phase for PbO. The size of the crystallites of the two semiconductors is of a nanometic order. Calcul the of gap energy indicate a shift towards high energies compared to massive crystals. This shift is due to the effect of the quantum confinement induced by the nanometric size of the crystallites of the semiconductors. These nanocrystals are used for the preparation of the nanocomposites of CuO/PS, CuO/PVC, PbO/PS and PbO/PVC by
simple insertion of CuO and PbO nanoparticles in the PS and PVC polymers. The analysis of the elaborated nanocomposites by X-ray diffraction has allowed to notice the incorporation of the CuO and PbO crystallites into the PS and PVC polymers matrixes and analysis by Raman and infrared spectroscopies has confirmed the presence of CuO and PbO crystallites in the PS and PVC matrixes by revealing specific vibration modes to the Cu-O and Pb-O bonds. The surface morphology and topography of thin films of nanocomposites were highlighted with the help of atomic force microscopy (AFM) and have shown homogeneous dispersion of CuO and PbO crystallites and a low surface roughness. the characterization by measurement of the optical absorption in the UV-Visible domain allows to observe the increase in optical absorption which is attributed to CuO and PbO nanocrystallites because PS and PVC are optically transparent in the UV-Visible domain. A shift of the gap energy of the nanocomposites compared with the gap energy of the pure polymers and the massive crystallites of CuO and PbO was observed. This variation in gap energy is the result of the new optical behavior of the prepared nanocomposites.
The optical characterization by the measure of the photoluminescence has shown that the elaborated samples present intense luminescence bands in the visible range, hence the possibility of consider these matrices as optically active media and can be used for the making devices of specific optics properties.
Diplôme : Doctorat en sciences En ligne : ../theses/physique/TRO7142.pdf Format de la ressource électronique : Permalink : https://bu.umc.edu.dz/md/index.php?lvl=notice_display&id=10460 Exemplaires (1)
Code-barres Cote Support Localisation Section Disponibilité TRO/7142 TRO/7142 Thèse Bibliothèque principale Thèses Disponible
Titre : Elaboration et caracterisation structurale et optique de matrices dielectriques dopees par des nanomateriaux Type de document : texte imprimé Auteurs : Bouzid Bouamra, Auteur ; M. Sebais, Directeur de thèse Editeur : Constantine : Université Mentouri Constantine Année de publication : 2015 Importance : 72 f. Format : 30 cm. Note générale : 2 copies imprimées disponibles
Langues : Français (fre) Tags : Nanocomposites KBr/KSr2Br5 KCl/KSr2Cl5 Monocristaux KBr et KCl DRX Absorption optique Radioluminescence Single crystals KBr and KCl XRD optical absorption ?????? ????????KCl?KBr ???????? ?????? ?????????? ??????? Index. décimale : 530 Physique Résumé : This work focused on the development and characterization of single crystals of KCl and KBr pure and doped by the particles of SrCl2 (H2O). The prepared nanocompositesKBr /KSr2Br5 andKCl / KSr2Cl5 were the subject of a structural and optical characterization by various methods suited to the study of the properties of nanomaterials. Simples (single crystals) of the materials prepared using the Czochralski method have cylindrical morphology with a diameter of 08 to 20mm and up to 80mm length. Several complementary techniques were used to structurally and optically characterize the elaborated materials to highlight their structural features and their optical properties.
The characterization by X-ray diffraction showed:
- That pure matrices of KCl and KBr have cubic single crystal structure and have orientation along the crystallographic axis [100].
- That the doped matrices kept their appearance despite the incorporation of nanoparticles after doping.
- That during the preparation of the samples which occurs at high temperature, the doping particles have chemically reacted with the host matrix and permit the in situ synthesis of the particles of KSr2Cl5andKSr2Br5.
- That the crystallites size of KSr2Cl5 and KSr2Br5 are nanoscale order
- That the quality of the synthesized crystallites KSr2Cl5 and KSr2Br5 is good sight of the
importance of the intensity of the diffraction peaks The characterization by Raman and IR spectroscopy has not given clear informations as there is little prior scientific work on the vibration modes of the elaborated compounds to compare and confirm our results.
- There is an absence of Raman peaks, which means that the crystallites KSr2Cl5 and KSr2Br5 located deep (within the matrix), the emitted radiation can be absorbed (decreased) by the matrix and not detected
Characterization by measuring the optical absorption revealed:
- The pure KCl and KBr host matrices are transparent in the near infrared - visible - near
ultraviolet.
- That the prepared nanocompositesKCl / KSr2Cl5 and KBr / KSr2Br5 have absorption bands in the visible range.
- That the optical gap of the prepared nanocomposites is lower than in pure KCl and KBr matrices.
Characterization by radioluminescence at room temperature showed:
-that prepared nanocompositesKCl / KSr2Cl5 and KBr / KSr2Br5 exhibit luminescence in the visible range. This characteristic makes these materials candidates which might come in the manufacture of components for optical systems using shorter wavelengths
Diplôme : Magistère En ligne : ../theses/physique/BOU6751.pdf Format de la ressource électronique : Permalink : https://bu.umc.edu.dz/md/index.php?lvl=notice_display&id=9864 Elaboration et caracterisation structurale et optique de matrices dielectriques dopees par des nanomateriaux [texte imprimé] / Bouzid Bouamra, Auteur ; M. Sebais, Directeur de thèse . - Constantine : Université Mentouri Constantine, 2015 . - 72 f. ; 30 cm.
2 copies imprimées disponibles
Langues : Français (fre)
Tags : Nanocomposites KBr/KSr2Br5 KCl/KSr2Cl5 Monocristaux KBr et KCl DRX Absorption optique Radioluminescence Single crystals KBr and KCl XRD optical absorption ?????? ????????KCl?KBr ???????? ?????? ?????????? ??????? Index. décimale : 530 Physique Résumé : This work focused on the development and characterization of single crystals of KCl and KBr pure and doped by the particles of SrCl2 (H2O). The prepared nanocompositesKBr /KSr2Br5 andKCl / KSr2Cl5 were the subject of a structural and optical characterization by various methods suited to the study of the properties of nanomaterials. Simples (single crystals) of the materials prepared using the Czochralski method have cylindrical morphology with a diameter of 08 to 20mm and up to 80mm length. Several complementary techniques were used to structurally and optically characterize the elaborated materials to highlight their structural features and their optical properties.
The characterization by X-ray diffraction showed:
- That pure matrices of KCl and KBr have cubic single crystal structure and have orientation along the crystallographic axis [100].
- That the doped matrices kept their appearance despite the incorporation of nanoparticles after doping.
- That during the preparation of the samples which occurs at high temperature, the doping particles have chemically reacted with the host matrix and permit the in situ synthesis of the particles of KSr2Cl5andKSr2Br5.
- That the crystallites size of KSr2Cl5 and KSr2Br5 are nanoscale order
- That the quality of the synthesized crystallites KSr2Cl5 and KSr2Br5 is good sight of the
importance of the intensity of the diffraction peaks The characterization by Raman and IR spectroscopy has not given clear informations as there is little prior scientific work on the vibration modes of the elaborated compounds to compare and confirm our results.
- There is an absence of Raman peaks, which means that the crystallites KSr2Cl5 and KSr2Br5 located deep (within the matrix), the emitted radiation can be absorbed (decreased) by the matrix and not detected
Characterization by measuring the optical absorption revealed:
- The pure KCl and KBr host matrices are transparent in the near infrared - visible - near
ultraviolet.
- That the prepared nanocompositesKCl / KSr2Cl5 and KBr / KSr2Br5 have absorption bands in the visible range.
- That the optical gap of the prepared nanocomposites is lower than in pure KCl and KBr matrices.
Characterization by radioluminescence at room temperature showed:
-that prepared nanocompositesKCl / KSr2Cl5 and KBr / KSr2Br5 exhibit luminescence in the visible range. This characteristic makes these materials candidates which might come in the manufacture of components for optical systems using shorter wavelengths
Diplôme : Magistère En ligne : ../theses/physique/BOU6751.pdf Format de la ressource électronique : Permalink : https://bu.umc.edu.dz/md/index.php?lvl=notice_display&id=9864 Exemplaires
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