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Preparation and Characterization of Sol-Gel derived Au Nanoparticle Dispersed Y_2O_3∶Eu Films

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Journal of Rare Earths 2005年第5期23卷 600-606页

作者：郭海张慰萍董宁楼立人尹民 Tillement O Mugnier J Bernstein E Brevet P F Structure Research Laboratory University of Science and Technology of China Academia Sinica Hefei 230026 China Department of Physics University of Science and Technology of China Hefei 230026 China department of Physics University of Science and Technology of China Hefei 230026 China laboratoire de Physico-chimie des materiaux Luminescents CNRS-UMR 5620 Universite Claude Bernard Lyon I 43 Boulevard du 11 Novembre 1918 69622 Villeurbanne Cedex France laboratoire de Spectrometrie Ionieque et Moleculaire CNRS-UMR 5579 Universite Claude Bernard Lyon I 43 Boulevard du 11 Novembre 1918 69622 Villeurbanne Cedex France department de Physique des materiaux CNRS-UMR 5586 Universite Claude Bernard Lyon I 43 Boulevard du 11 Novembre 1918 69622 Villeurbanne Cedex France laboratoire de Spectrometrie Ionieque et Moleculaire CNRS-UMR 5579 Universite Claude Bernard Lyon I 43 Boulevard du 11 Novembre 1918 69622 Villeurbanne Cedex France)

Gold nanoparticles dispersed Y2O3 films were prepared through a sol-gel method by using yttrium acetate and Au nanoparticles colloid as precursors. The films were characterized by X-ray diffraction （XRD）, transmission electron microscopy （TEM） and UV-VIS absorption spectra. XRD patterns and TEM images of Y2O3 ＋ Au films give the same resuits on structure and particle size as that of pure Y2O3 films. The surface plasma resonance （SPR） of Au nanoparticles in Y2O3 ＋ Au film was observed around 550 nm in the absorption spectrum and its position shifts to red with increasing annealing temperature is caused by the increase of dielectric constant of Y2O3 matrix and the size of Au nanoparticles. The second and third order nonlinear optical effects of Y2O3 ＋ Au films were also observed. The photoluminescent properties of Y2O3 ： Eu ＋ Au films were investigated and results indicate that there exist an energy transfer from Eu^3 ＋ to Au nanoparticles and this energy transfer decreases the emission of Eu^3 ＋ in Y2O3 ： Eu ＋ Au film.

关键词： sol-gel Y2O3 + Au films nanocomposite photoluminescence rare earths

Static and dynamic stability responses of multilayer functionally graded carbon nanotubes reinforced composite nanoplates via quasi 3D nonlocal strain gradient theory

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defence Technology（防务技术） 2022年第10期18卷 1778-1809页

作者： Ahmed Amine Daikh Mohamed Sid Ahmed Houari Mohamed Ouejdi Belarbi Salwa A.Mohamed Mohamed A.Eltaher laboratoire D'Etude des Structures et de Mecanique des materiaux Departement de Genie CivilFacultedes Sciences et de La TechnologieUniversite Mustapha Stambouli B.P.305R.P.29000MascaraAlgeria laboratoire de Genie Energetique et materiaux LGEMUniversite de BiskraB.P.145R.P07000BiskraAlgeria department of Engineering Mathematics Zagazig UniversityP.O.Box 44519ZagazigEgypt Faculty of Engineering Mechanical Engineering DepartmentKing Abdulaziz UniversityP.O.Box 80204JeddahSaudi Arabia Faculty of Engineering Mechanical Design and Production DepartmentZagazig UniversityP.O.Box 44519ZagazigEgypt

This manuscript presents the comprehensive study of thickness stretching effects on the free vibration,static stability and bending of multilayer functionally graded(FG)carbon nanotubes reinforced composite(CNTRC)*** nanoscale and microstructure influences are considered through a modified nonlocal strain gradient continuum *** on power-law functions,four different patterns of CNTs distribution are considered in this analysis,a uniform distribution UD,FG-V CNTRC,FG-X CNTRC,and FG-O CNTRC.A 3D kinematic shear deformation theory is proposed to include the stretching influence,which is neglected in classical ***'s principle is applied to derive the governing equations of motion and associated boundary *** solutions are developed based on Galerkin method to solve the governing equilibrium equations based on the generalized higher-order shear deformation theory and the nonlocal strain gradient theory and get the static bending,buckling loads,and natural frequencies of *** with previous works is presented.A detailed parametric analysis is carried out to highlight the impact of thickness stretching,length scale parameter(nonlocal),material scale parameter(gradient),CNTs distribution pattern,geometry of the plate,various boundary conditions and the total number of layers on the stresses,deformation,critical buckling loads and vibration *** new results are also reported in the current study,which will serve as a benchmark for future research.

关键词： 3D shear deformation theory Free vibration Buckling Bending Galerkin method Functionally graded nanotube Nonlocal strain gradient theory

Electronic structure and magnetic properties of rare-earth perovskite gallates from first principles

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Chinese Physics B 2017年第1期26卷 375-385页

作者： A Dahani H Alamri B Merabet A Zaoui S Kacimi A Boukortt M Bejar laboratoire de Physique Computationnelle des materiaux Universite Dfillali Liabes de Sidi Bel-Abbes Sidi Bel-Abbes 22000 Algeria Universite Moulay Tahar Faculte de Technologie Saida 20000 Algeria Umm AI-Qura University Physics Department-University College Makkah Saudi Arabia Universite Mustapha Stambouli Faculte de Technologie Mascara 29000 Algeria Elaboration Characterization Physico-Mechanics of Materials and Metallurgical Laboratory ECP3M Faculty of Sciences and Technology Abdelhamid Ibn Badis University of Mostaganem Mostaganem 27000 Algeria laboratoire de Physique Appliquee Faculte des Sciences Universite de Sfax Sfax 3000 Tunisia

The density functional calculation is performed for centrosymmetric（La–Pm） GaO3 rare earth gallates, using a full potential linear augmented plane wave method with the LSDA and LSDA＋U exchange correlation to treat highly correlated electrons due to the very localized 4f orbitals of rare earth elements, and explore the influence of U = 0.478 Ry on the magnetic phase stability and the densities of states. LSDA＋U calculation shows that the ferromagnetic（FM） state of RGaO3 is energetically more favorable than the anti-ferromagnetic（AFM） one, except for LaGaO3 where the NM state is the lowest in energy. The energy band gaps of RGaO3 are found to be in the range of 3.8–4.0 eV, indicating the semiconductor character with a large gap.

关键词： DFT+U+SO strongly correlated electron systems magnetism rare earth gallates perovskites

Extraction and Characterization of Aucoumea klaineana Pierre (Okoume) Extractives

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Journal of Renewable Materials 2019年第6期7卷 517-522页

作者： Engozogho Anris Starlin Peguy Bikoro Bi Athomo Arsene Vidal Marcia denaud Louis Safou Tchiama Rodrigue Charrier Bertrand CNRS/Univ Pau&Pays Adour Institut des Sciences Analytiques et de Physico-Chimie pour l’Environnement et les Matériaux-XylomatUMR525440004Mont de MarsanFrance laboratoire de Recherche et de Valorisation du Matériau Bois(LaReVa Bois).Ecole Normale Supérieure d’Enseignement Technique(ENSET).BP.3989 LibrevilleGabon laboratoire des Substances Naturelles et de Synthèses Organométalliques(LASNSOM).Unitéde Recherche en chimie(URChi).BP.941 Universitédes Sciences et Techniques de Masuku.Franceville Gabon laboratoire Bourguignon des Matériaux et Procédé ClunyFrance Ecole Catholique d'Arts et Métiers(ECAM) 40 Montée Saint Barthéllemy69321Lyon cedex O5France-Lyon

In order to promote convenient strategies for the utilization of wood wastes from aucoumea klaineana pierre(okoume)timber industry,various chemical analysis were carried out on samples from different *** extractives content of the bark,sapwood and heartwood of okoume were *** analyses were performed and the stiasny number was *** was found that the bark was richer in fatty acid of high molecular weight while the sapwood was rich in fatty acid of low molecular *** condensed tannins content varied according to the origin and the part of the *** new findings should be useful for green okoume based tannin adhesives.

关键词： Extractibles fatty acids tannins polyphenols stiasny number TGA

Field-effect passivation on silicon nanowire solar cells

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Nano Research 2015年第2期8卷 673-681页

作者： Anna Dalmau Mallorqui Esther Alarcon-Llado Ignasi Canales Mundet Amirreza Kiani Benedicte demaurex Stefaan de Wolf Andreas Menzel Margrit Zacharias Anna Fontcuberta i Morra laboratoire des materiaux Semiconducteurs Ecole Polytechnique Federale de Lausanne 1015 Lausanne Switzerland Photovoltaics and Thin Film Electronics Laboratory Institute o fMicroengineering (IMT) E-cole Polytechnique Federale de Lausanne 2000 Neuchotel Switzerland Nanotechnology Institute of Microsystems Engineering(IMTEK) Albert-Ludwigs-University 79110 Freiburg Germany

Surface recombination represents a handicap for high-efficiency solar cells. This is especially important for nanowire array solar cells, where the surface-to-volume ratio is greatly enhanced. Here, the effect of different passivation materials on the effective recombination and on the device performance is experimentally analyzed. Our solar cells are large area top-down axial n-p junction silicon nanowires fabricated by means of Near-Field Phase-Shift Lithography （NF-PSL）. We report an efficiency of 9.9% for the best cell, passivated with a SiO2/SiNx stack. The impact of the presence of a surface fixed charge density at the silicon/oxide interface is studied.

关键词： field-effect passivation nanowire surface recombination solar cell

Versatile synthesis of cadalene and iso-cadalene from himachalene mixtures:Evidence and application of unprecedented rearrangements

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Chinese Chemical Letters 2020年第7期31卷 1851-1854页

作者： Mustapha Ait El Had Abdelouahd Oukhrib Mohamed Zaki Martine Urrutigoity Ahmed Benharref Remi Chauvin laboratoire de chimie Biomoleculaire Substances Naturelies et Reactivite(URAC 16)Faculte des Sciences SemlaliaUniversite Cadi AyyadB.P.2390MarrakechMorocco CNRS LCC(Laboratoire de Chimie de Coordination)BP 4409931077Toulouse Cedex 4France INP-ENSIACET 4 allee Emile Monso31030Toulouse CedexFrance Universite de Toulouse UPSICT-FR 259931062Toulouse Cedex 9France

From a mixture of α-,β-and y-himachalenes extracted from waste wood of Atlas cedar(Cedrus atlantica),cadalene(1,6-dimethyl-4-isopropylnaphthalene)and iso-cadalene(1,6-dimethyl-3-isopropylnaphthalene)were produced in two steps with up to 71%±5%yield through the ar-himachalene intermediate using I2 and/or AlCl3 as *** selectivity is shown to sharply depend on the operating conditions:while I2/AlCl3 in dichloromethane promotes the formation of cadalene,the formation of iso-cadalene is favored in the presence of AlCl3 in *** bicyclic aromatic compounds were thus obtained through unique rearrangements involving sequential C—C bond cleavage/fo rmation and hydride transfer *** the absence of AlCl3 or I2,dihydrocurcumene was also found to be formed with up to 70%selectivity.A tentative mechanism is proposed and discussed.

关键词： Aromatic reactivity Cadalenes Dihydrocurcumene Himachalenes Rearrangements

Preparation and Characterization of Hybrid Luminescence Mesoporous MCM-48 Doped with Eu( Ⅲ ) Complex

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Journal of Rare Earths 2004年第Z1期22卷 144-146页

作者： Meng Qingguo Li Huanrong Peng Chunyun Zhang Hongjie Boutinaud P Franville A C Mahiou R Key Laboratory of Rare Earth Chemistry and Physics Changchun Institute of Applied Chemistry Chinese Academy of Sciences Changchun 130022 China laboratoire des materiaux Inorganiques UMR CNRS 6002 Universite Blaise-Pascal et ENSCCF 24 Avenue des LandaisF-63177 Aubiere CedexFrance Key Laboratory of Rare Earth Chemistry and Physics Changchun Institute of Applied Chemistry Chinese Academy of Sciences Changchun 130022 China Key Laboratory of Rare Earth Chemistry and Physics Changchun Institute of Applied Chemistry Chinese Academy of Sciences Changchun 130022 China Key Laboratory of Rare Earth Chemistry and Physics Changchun Institute of Applied Chemistry Chinese Academy of Sciences Changchun 130022 China Laboratoire des Materiaux Inorganiques UMR CNRS 6002 Universite Blaise-Pascal et ENSCCF 24 Avenue des Landais F-63177 Aubiere Cedex France Laboratoire des Materiaux Inorganiques UMR CNRS 6002 Universite Blaise-Pascal et ENSCCF 24 Avenue des Landais F-63177 Aubiere Cedex France Laboratoire des Materiaux Inorganiques UMR CNRS 6002 Universite Blaise-Pascal et ENSCCF 24 Avenue des Landais F-63177 Aubiere Cedex France

The preparation of hybrid mesoporous MCM-48 grafted by vinyl group via post-grafting process was reported and studied by X-ray diffraction, BET and 29Si solid MAS *** organic β-diketonate Europium complex the corresp... 详细信息

关键词： mesoporous hybrid materials rare earths

Effect of Strontium on Structure and Superficial Area of La_(2)O_(3)

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Advances in Materials Physics and Chemistry 2012年第1期2卷 31-36页

作者： Radia Imane Fertout Madani Ghelamallah Soufi Kacimi laboratoire de materiaux et Catalyse Departement de ChimieFaculte des SciencesUniversite Djillali LiabesSidi Bel AbbesAlgerie laboratoire de materiaux Applications et EnvironnementDepartement des Sciences de la MatiereFaculte des Sciences et de la TechnologieUniversite de MascaraMascaraAlgerie Centre Universitaire d’Ain-Temouchent(CUAT) Ain-TemouchentAlgerie

Recently, lanthanum oxide doped by group IIA elements may strongly influence solid state reaction. A series of samples, noted LaSrX (where X = % atomic of strontium) have been prepared by hydrolysis, in neutral medium from La2O3 and SrCO3. These samples were calcined under air at 450?C and 1150?C then characterized by specific surface area (BET), X-ray diffraction, scanning electron microscopy (SEM), thermogravimetry (TG) and differential thermal analysis (DTA). Obtained results show that after calcinations at: 1) 450?C, the addition of strontium is without effect on surface of La2O3 and the XRD analysis revealed no interaction between lanthanum oxide and strontium carbonate;2) 1150?C, the sintering of the samples is very important, reduction of 70% of surfaces compared to the samples calcined at 450?C;XRD results show that LaSrX are formed principally by two oxides: SrLa2O4 and La2O3, which is confirmed by SEM method. The reaction between La2O3 and SrCO3 showed three endothermic weight losses;elimination of water, a partial dehydroxylation of La(OH)3 and formation of La2O2CO3 and La2(CO3)3.

关键词： La_(2)O_(3) Strontium Calcination Surface Structure TG-DTA

Synthesis, Crystal Structure and Infrared Characterization of Bis(4-dimethylamino-pyridinium) Tetrachlorocuprate

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American Journal of Analytical Chemistry 2015年第5期6卷 446-456页

作者： Mahjouba Ben Nasr Frédéric Lefebvre Chérif Ben Nasr laboratoire de chimie des Matériaux Faculté des Sciences de Bizerte Université de Carthage Zarzouna Tunisie laboratoire de chimie Organométallique de Surface (LCOMS) Ecole Supérieure de Chimie Physique Electronique Villeurbanne France

The chemical preparation, crystal structure and spectroscopic characterization of a novel organic-inorganic hybrid material, bis(4-dimethylaminopyridinium) tetrachlorocuprate, have been reported. This compound crystallizes in the monoclinic system in space group C2/c and cell parameters a = 12.4356 (18), b = 12.0901 (17), c = 14.094 (2) Å, β = 115.303 (2)°, Z = 4 and V = 1915.8 (5) Å3. In the title salt, (C7H11N2)2CuCl4, both 4-dimethylaminopyridinium cations are protonated at their pyridine N atoms. The geometry of the CuCl2-4 ions is intermediate between tetrahedral and square planar. The atomic arrangement can be described by an alternation of inorganic layers built up by tetrachlorocuprate anions and organic layers formed by 4-dimethylaminopyridinium cations. The organic layers are located in sandwich between the inorganic layers. The anionic and cationic layers are held together by N-H···Cl and C-H···Cl hydrogen bonds into a three-dimensional network. The individual cations are π-π stacked with their neighbors at a distance of 3.7622 (5) Å. The vibrational absorption bands were identified by infrared spectroscopy and DFT calculations allowed their attribution.

关键词： Crystal Structure 4-Dimethylaminopyridine Hydrogen Bonds π-π Interactions DFT Calculations