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Partager le résultat de cette recherche Interroger des sources externesElaboration et caractérisation structurale et optique des nanocristaux du semiconducteur Sb2O3 et de l'oxyde Y2O3 dispersés dans les matrices cristallines des halogénures alcalins KBr, KCl et NaCl / Lazhar Bouhdjer
Titre : Elaboration et caractérisation structurale et optique des nanocristaux du semiconducteur Sb2O3 et de l'oxyde Y2O3 dispersés dans les matrices cristallines des halogénures alcalins KBr, KCl et NaCl Type de document : texte imprimé Auteurs : Lazhar Bouhdjer, Auteur ; M. Sebais, Directeur de thèse Editeur : constantine [Algérie] : Université Constantine 1 Année de publication : 2013 Importance : 93 f. Format : 30 cm. Note générale : 2 copies imprimées disponibles Langues : Français (fre) Tags : semi-conducteur Sb2O3 oxyde de terre rare Y2O3 Czochralski DRX FT-IR ?-Ramn absorption UV-Visible photoluminescence semiconductor (Sb2O3) rare earth oxide (Y2O3) XRD IR ?-
Ramn Uvi-Vis ???????? ???????????
????? ????????? ???????? ?????? ???? ????? ? ?????? ?? ??? ??????? ?????? ?????????? ?????? MEB (Sb2O3)??? ?????? (Y2O3)??????
?????? ?????? XIndex. décimale : 530 Physique Résumé : Preparation and structural and optical characterization of semiconductor nanocrystals
of Sb2O3 and Y2O3 oxide dispersed in a crystalline matrices of alkali halides KBr, KCl
and NaCl.
In this work antimony oxide (Sb2O3) and yttrium oxide (Y2O3) nanocrystals doped KBr, KCl and NaCl single crystals have been grown by Czochralski (Cz) method.
The effects of doping on the structural and optical properties of the host matrices have
been studied.
The structural studies of samples were performed by XRD, μ-Raman, IR spectroscopy, scanning electron microscopy (SEM) and energy dispersive X-ray analysis (EDX). The treatment of XRD spectrum confirms the existence of crystallites of dopants (Sb2O3 and Y2O3) in the nanometer regime; on the other hand, the existence of the stable monoclinic phase crystallites (Y2O3) under atmospheric conditions reconfirms presence of (Y2O3) in nanoscale.
Studies by μ-Raman and IR confirmed the presence of chemical bonds Y—O and Sb—O in the different matrices.
The morphological study using the scanning electron microscope (SEM) shows that the micron grains scattered on the surface. The volume of these aggregates is due to the fact that the nanocrystals have a tendency to reduce its free energy (Gibbs energy) of surface.
The optical absorption and photoluminescence shows that the optical gaps of the crystallites (Sb2O3 and Y2O3) have been shifted to the high energy due to the quantum confinement effect of the charges.
The samples have important intense luminescence properties in the ultraviolet range. This feature makes these materials candidates which might come in the manufacture of components for optical systems using shorter wavelengths.Diplôme : Doctorat en sciences En ligne : ../theses/physique/BOU6378.pdf Format de la ressource électronique : Permalink : https://bu.umc.edu.dz/md/index.php?lvl=notice_display&id=9379 Elaboration et caractérisation structurale et optique des nanocristaux du semiconducteur Sb2O3 et de l'oxyde Y2O3 dispersés dans les matrices cristallines des halogénures alcalins KBr, KCl et NaCl [texte imprimé] / Lazhar Bouhdjer, Auteur ; M. Sebais, Directeur de thèse . - constantine (Route ain el bey, Algérie) : Université Constantine 1, 2013 . - 93 f. ; 30 cm.
2 copies imprimées disponibles
Langues : Français (fre)
Tags : semi-conducteur Sb2O3 oxyde de terre rare Y2O3 Czochralski DRX FT-IR ?-Ramn absorption UV-Visible photoluminescence semiconductor (Sb2O3) rare earth oxide (Y2O3) XRD IR ?-
Ramn Uvi-Vis ???????? ???????????
????? ????????? ???????? ?????? ???? ????? ? ?????? ?? ??? ??????? ?????? ?????????? ?????? MEB (Sb2O3)??? ?????? (Y2O3)??????
?????? ?????? XIndex. décimale : 530 Physique Résumé : Preparation and structural and optical characterization of semiconductor nanocrystals
of Sb2O3 and Y2O3 oxide dispersed in a crystalline matrices of alkali halides KBr, KCl
and NaCl.
In this work antimony oxide (Sb2O3) and yttrium oxide (Y2O3) nanocrystals doped KBr, KCl and NaCl single crystals have been grown by Czochralski (Cz) method.
The effects of doping on the structural and optical properties of the host matrices have
been studied.
The structural studies of samples were performed by XRD, μ-Raman, IR spectroscopy, scanning electron microscopy (SEM) and energy dispersive X-ray analysis (EDX). The treatment of XRD spectrum confirms the existence of crystallites of dopants (Sb2O3 and Y2O3) in the nanometer regime; on the other hand, the existence of the stable monoclinic phase crystallites (Y2O3) under atmospheric conditions reconfirms presence of (Y2O3) in nanoscale.
Studies by μ-Raman and IR confirmed the presence of chemical bonds Y—O and Sb—O in the different matrices.
The morphological study using the scanning electron microscope (SEM) shows that the micron grains scattered on the surface. The volume of these aggregates is due to the fact that the nanocrystals have a tendency to reduce its free energy (Gibbs energy) of surface.
The optical absorption and photoluminescence shows that the optical gaps of the crystallites (Sb2O3 and Y2O3) have been shifted to the high energy due to the quantum confinement effect of the charges.
The samples have important intense luminescence properties in the ultraviolet range. This feature makes these materials candidates which might come in the manufacture of components for optical systems using shorter wavelengths.Diplôme : Doctorat en sciences En ligne : ../theses/physique/BOU6378.pdf Format de la ressource électronique : Permalink : https://bu.umc.edu.dz/md/index.php?lvl=notice_display&id=9379 Exemplaires
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Titre : Etude structurale et optique de matériaux composites Type de document : texte imprimé Auteurs : Mouloud Hemara, Auteur ; Zeineddine Ouili, Directeur de thèse Editeur : Constantine : Université Mentouri Constantine Année de publication : 2015 Importance : 75 f. Format : 30 cm. Note générale : 2 copies imprimées disponibles
Langues : Français (fre) Tags : composites nanocomposites oxyde niobium (Nb2O5 ) Czochralski DRX ?-Raman FT-IR absorption UV-Visible radioluminescence niobium oxide ( Nb2O5 ) XRD UV-Visible absorption ???????? ?????? ?????? ????? ????????? Nb2O5 ????? ???? ????? ?????? ???? ??? ????? ??????? ????? ??????? ???????? ?????? ?? ?????? ?????? ?????? ? ??? ???????? ????????? ??????? Index. décimale : 530 Physique Résumé : This work is the development of single crystals KBr and KCl pure and doped with Nb crystallites was carried out by the drawing method according to the principle of Czochralski growth .
The structural study and optical different matrices , alkali halides to know the effects of doping on their properties.
The structural analysis of the samples prepared was carried out by the X-ray diffraction and IR spectroscopy and micro -Raman .
XRD revealed the incorporation of Nb crystallite in the crystal matrix , and produces another Nano phase ( Nb2O5 ) .
The μ -Raman and FT-IR spectroscopy to confirm the results of the characterization by X-ray diffraction as regards the presence of the phase Nb2O5 and existed the Nb- O chemical bond in the crystal matrices KBr and KCl .
The optical absorption study for the nanocomposites prepared Nb / Nb and KBr / KCl show a transparent matrices in the Visible and Ultraviolet related field , When these matrices are doped with Nb2O5 nanocrystallites their optical gap decrease.
The optical characterization radioluminescence for samples prepared shown that this low-intensity luminescence in the visible range when excited by radiation X.
Diplôme : Magistère En ligne : ../theses/physique/HEM6747.pdf Permalink : https://bu.umc.edu.dz/md/index.php?lvl=notice_display&id=9869 Etude structurale et optique de matériaux composites [texte imprimé] / Mouloud Hemara, Auteur ; Zeineddine Ouili, Directeur de thèse . - Constantine : Université Mentouri Constantine, 2015 . - 75 f. ; 30 cm.
2 copies imprimées disponibles
Langues : Français (fre)
Tags : composites nanocomposites oxyde niobium (Nb2O5 ) Czochralski DRX ?-Raman FT-IR absorption UV-Visible radioluminescence niobium oxide ( Nb2O5 ) XRD UV-Visible absorption ???????? ?????? ?????? ????? ????????? Nb2O5 ????? ???? ????? ?????? ???? ??? ????? ??????? ????? ??????? ???????? ?????? ?? ?????? ?????? ?????? ? ??? ???????? ????????? ??????? Index. décimale : 530 Physique Résumé : This work is the development of single crystals KBr and KCl pure and doped with Nb crystallites was carried out by the drawing method according to the principle of Czochralski growth .
The structural study and optical different matrices , alkali halides to know the effects of doping on their properties.
The structural analysis of the samples prepared was carried out by the X-ray diffraction and IR spectroscopy and micro -Raman .
XRD revealed the incorporation of Nb crystallite in the crystal matrix , and produces another Nano phase ( Nb2O5 ) .
The μ -Raman and FT-IR spectroscopy to confirm the results of the characterization by X-ray diffraction as regards the presence of the phase Nb2O5 and existed the Nb- O chemical bond in the crystal matrices KBr and KCl .
The optical absorption study for the nanocomposites prepared Nb / Nb and KBr / KCl show a transparent matrices in the Visible and Ultraviolet related field , When these matrices are doped with Nb2O5 nanocrystallites their optical gap decrease.
The optical characterization radioluminescence for samples prepared shown that this low-intensity luminescence in the visible range when excited by radiation X.
Diplôme : Magistère En ligne : ../theses/physique/HEM6747.pdf Permalink : https://bu.umc.edu.dz/md/index.php?lvl=notice_display&id=9869 Exemplaires
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Titre : Elaboration et caractérisation de matériaux composites à base des nanoparticules du semi-conducteur CuO et de l’oxyde de terre rare Dy2O3 dispersées dans les matrices diélectriques KBr, KCl et NaCl. Type de document : texte imprimé Auteurs : Samiya Addala, Auteur ; O. Halimi, Directeur de thèse Editeur : Constantine : Université Mentouri Constantine Année de publication : 2015 Importance : 106 f. Format : 30 cm. Note générale : 2 copies imprimées disponibles
Langues : Français (fre) Tags : NaCl KCl KBr semiconducteur (CuO) oxyde de terre rare (Dy2O3) Czochralski DRX FT-IR µ-Ramn MEB-EDX UV-Visible photoluminescence semiconductor (CuO) rare earth oxide (Dy2O3) XRD IR ?-Ramn Uvi-Vis ???????? ??????????? ??? ?????? )CuO( ??????)Dy2O3) ????? ????????? ?????? ???? X ????????
?????? ???? ????? ? ?????? ?? ??? ??????? ?????? ?????????? ?????? MEBIndex. décimale : 530 Physique Résumé : Elaboration and characterization of composite materials based on nanoparticles of the semiconductor CuO and the rare earth oxide Dy2O3 dispersed in the dielectric matrix of KBr, KCl and NaCl In this work copper oxide (CuO) and dysprosium oxide (Dy2O3) nanocrystals doped KBr, KCl and NaCl single crystals have been grown by Czochralski (Cz) method.
The effects of doping on the structural and optical properties of the host matrices have been studied.
The structural studies of samples were performed by XRD, μ-Raman, IR spectroscopy, scanning electron microscopy (SEM) and energy dispersive X-ray analysis (EDX).The treatment of XRD spectrum confirms the existence of crystallites of dopants (Sb2O3 and Y2O3) in the nanometer regime;Studies by μ-Raman and IR confirmed the
presence of chemical bonds Dy—Oand Cu—O in the different matrices.
The morphological study using the scanning electron microscope (SEM) shows that the micron grains scattered on the surface. The microscopic size of these aggregates is due to the fact that the nanocrystals have a tendency to reduce its free energy (Gibbs energy) of surface. The energy dispersive X-ray analysis (EDX) spectrum indicates that
the NaCl:CuO single crystal has a very high purity.
The optical absorption and photoluminescence shows that the optical gaps of the crystallites (CuO and Dy2O3) have been shifted to the high energy due to the quantum confinement effect of the charges.
The samples have important intense luminescence properties in the ultraviolet range. This feature makes these materials candidates which might come in the manufacture of components for optical systems using shorter wavelengths.
Diplôme : Doctorat en sciences En ligne : ../theses/physique/ADD6746.pdf Format de la ressource électronique : Permalink : https://bu.umc.edu.dz/md/index.php?lvl=notice_display&id=9870 Elaboration et caractérisation de matériaux composites à base des nanoparticules du semi-conducteur CuO et de l’oxyde de terre rare Dy2O3 dispersées dans les matrices diélectriques KBr, KCl et NaCl. [texte imprimé] / Samiya Addala, Auteur ; O. Halimi, Directeur de thèse . - Constantine : Université Mentouri Constantine, 2015 . - 106 f. ; 30 cm.
2 copies imprimées disponibles
Langues : Français (fre)
Tags : NaCl KCl KBr semiconducteur (CuO) oxyde de terre rare (Dy2O3) Czochralski DRX FT-IR µ-Ramn MEB-EDX UV-Visible photoluminescence semiconductor (CuO) rare earth oxide (Dy2O3) XRD IR ?-Ramn Uvi-Vis ???????? ??????????? ??? ?????? )CuO( ??????)Dy2O3) ????? ????????? ?????? ???? X ????????
?????? ???? ????? ? ?????? ?? ??? ??????? ?????? ?????????? ?????? MEBIndex. décimale : 530 Physique Résumé : Elaboration and characterization of composite materials based on nanoparticles of the semiconductor CuO and the rare earth oxide Dy2O3 dispersed in the dielectric matrix of KBr, KCl and NaCl In this work copper oxide (CuO) and dysprosium oxide (Dy2O3) nanocrystals doped KBr, KCl and NaCl single crystals have been grown by Czochralski (Cz) method.
The effects of doping on the structural and optical properties of the host matrices have been studied.
The structural studies of samples were performed by XRD, μ-Raman, IR spectroscopy, scanning electron microscopy (SEM) and energy dispersive X-ray analysis (EDX).The treatment of XRD spectrum confirms the existence of crystallites of dopants (Sb2O3 and Y2O3) in the nanometer regime;Studies by μ-Raman and IR confirmed the
presence of chemical bonds Dy—Oand Cu—O in the different matrices.
The morphological study using the scanning electron microscope (SEM) shows that the micron grains scattered on the surface. The microscopic size of these aggregates is due to the fact that the nanocrystals have a tendency to reduce its free energy (Gibbs energy) of surface. The energy dispersive X-ray analysis (EDX) spectrum indicates that
the NaCl:CuO single crystal has a very high purity.
The optical absorption and photoluminescence shows that the optical gaps of the crystallites (CuO and Dy2O3) have been shifted to the high energy due to the quantum confinement effect of the charges.
The samples have important intense luminescence properties in the ultraviolet range. This feature makes these materials candidates which might come in the manufacture of components for optical systems using shorter wavelengths.
Diplôme : Doctorat en sciences En ligne : ../theses/physique/ADD6746.pdf Format de la ressource électronique : Permalink : https://bu.umc.edu.dz/md/index.php?lvl=notice_display&id=9870 Exemplaires
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Titre : Etude des propriétés structurales et optiques des matrices cristallines KCl et KBr dopées par les agrégats des terres rares Er, Ce et Lu Type de document : texte imprimé Auteurs : Sadek Kara, Auteur ; M. Sebais, Directeur de thèse Editeur : جامعة الإخوة منتوري قسنطينة Année de publication : 2017 Importance : 104 f. Format : 30 cm. Note générale : 2 copies imprimées disponibles
Langues : Français (fre) Tags : chlorure de terre rare (ErCl3, CeCl3) oxyde de terre rare Lu2O3 Czochralski DRX FT-IR, ?-Ramn absorption UV-visible photoluminescence radio-luminescence Rare earth chloride (ErCl3, CeCl3) rare earth oxide Lu2O3 UV-Visible absorption Radio-luminescence ?????? ??????? ??????? ??????? ) (CeCl3?ErCl3????? ??????? ??????? ???????) (Lu2O3?????
???????????????? ???? X???????? ?????? ???? ????? ? ?????? ?? ??? ??????? ??????? ??????Index. décimale : 530 Physique Résumé : The aim of this work is to develop and characterize the single crystals of alkali
halide (KCl and KBr) doped with rare earth elements (Er, Ce and Lu) using the crystal
growth technique from melt phase according to the principle of the Czochralski method.
The single crystals obtained are on cylindrical morphology. For the purposes of their
characterization, the single crystals are cut by pellet cleavage whose plane faces are
perpendicular to the growth axis which is parallel to the crystallographic axis of KCl or
KBr.
Structural studies on elaborated materials using X-ray diffraction, FT-IR and
Raman spectroscopies have shown that the KCl and KBr monocrystals (pure and
doped) have a monocrystalline character, and in these crystalline matrices theaggregates
of rare earths elements (ErCl3, CeCl3 and Lu2O3) are incorporated. The presence of
these aggregates induced stresses in the crystal lattice of the matrices KCl and KBr.
Certain impurities such as H2O and CO2 have also been revealed and their come from
the environment during the growth operation (uncontrolled atmosphere) or the
characterization of the samples.
Optical investigations by absorption, photoluminescence and radioluminescence
were carried out to demonstrate the optical properties of KCl and KBr single crystals
doped with rare earth elements Er, Ce and Lu and also to confirm the presence of
dopants in the host matrices. Observation of the optical absorption spectra shows that
all the samples studied are transparent in the IR domain but have an important
absorption in the UV-VIS domain. Bands corresponding to the absorption by the doping
elements and to the colored centers present in the matrices KCl and KBr are also visible
on the spectra.
The photoluminescence of the samples shows an emission bands due to radiative
electronic transitions of the rare earth elements, demonstrating that the matrices studied
can be considered as luminophores. The relatively high concentration of the doping
elements leads to a decrease in the intensity of the observed luminescence bands; this
decrease may be due to a mutual influence of the rare earth atoms incorporated in the
KCl and KBr matrices. The analysis by radio-luminescence shows intense emission
bands and shows that the elaborated materials can be used as scintillators for the
detection of X-rays.Diplôme : Doctorat en sciences En ligne : ../theses/physique/KAR7113.pdf Format de la ressource électronique : Permalink : https://bu.umc.edu.dz/md/index.php?lvl=notice_display&id=10488 Etude des propriétés structurales et optiques des matrices cristallines KCl et KBr dopées par les agrégats des terres rares Er, Ce et Lu [texte imprimé] / Sadek Kara, Auteur ; M. Sebais, Directeur de thèse . - [S.l.] : جامعة الإخوة منتوري قسنطينة, 2017 . - 104 f. ; 30 cm.
2 copies imprimées disponibles
Langues : Français (fre)
Tags : chlorure de terre rare (ErCl3, CeCl3) oxyde de terre rare Lu2O3 Czochralski DRX FT-IR, ?-Ramn absorption UV-visible photoluminescence radio-luminescence Rare earth chloride (ErCl3, CeCl3) rare earth oxide Lu2O3 UV-Visible absorption Radio-luminescence ?????? ??????? ??????? ??????? ) (CeCl3?ErCl3????? ??????? ??????? ???????) (Lu2O3?????
???????????????? ???? X???????? ?????? ???? ????? ? ?????? ?? ??? ??????? ??????? ??????Index. décimale : 530 Physique Résumé : The aim of this work is to develop and characterize the single crystals of alkali
halide (KCl and KBr) doped with rare earth elements (Er, Ce and Lu) using the crystal
growth technique from melt phase according to the principle of the Czochralski method.
The single crystals obtained are on cylindrical morphology. For the purposes of their
characterization, the single crystals are cut by pellet cleavage whose plane faces are
perpendicular to the growth axis which is parallel to the crystallographic axis of KCl or
KBr.
Structural studies on elaborated materials using X-ray diffraction, FT-IR and
Raman spectroscopies have shown that the KCl and KBr monocrystals (pure and
doped) have a monocrystalline character, and in these crystalline matrices theaggregates
of rare earths elements (ErCl3, CeCl3 and Lu2O3) are incorporated. The presence of
these aggregates induced stresses in the crystal lattice of the matrices KCl and KBr.
Certain impurities such as H2O and CO2 have also been revealed and their come from
the environment during the growth operation (uncontrolled atmosphere) or the
characterization of the samples.
Optical investigations by absorption, photoluminescence and radioluminescence
were carried out to demonstrate the optical properties of KCl and KBr single crystals
doped with rare earth elements Er, Ce and Lu and also to confirm the presence of
dopants in the host matrices. Observation of the optical absorption spectra shows that
all the samples studied are transparent in the IR domain but have an important
absorption in the UV-VIS domain. Bands corresponding to the absorption by the doping
elements and to the colored centers present in the matrices KCl and KBr are also visible
on the spectra.
The photoluminescence of the samples shows an emission bands due to radiative
electronic transitions of the rare earth elements, demonstrating that the matrices studied
can be considered as luminophores. The relatively high concentration of the doping
elements leads to a decrease in the intensity of the observed luminescence bands; this
decrease may be due to a mutual influence of the rare earth atoms incorporated in the
KCl and KBr matrices. The analysis by radio-luminescence shows intense emission
bands and shows that the elaborated materials can be used as scintillators for the
detection of X-rays.Diplôme : Doctorat en sciences En ligne : ../theses/physique/KAR7113.pdf Format de la ressource électronique : Permalink : https://bu.umc.edu.dz/md/index.php?lvl=notice_display&id=10488 Exemplaires
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