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Indium doping effect on properties of ZnO nanoparticles synthesized by sol–gel method

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Chinese Physics B 2019年第4期28卷 342-348页

作者： S Mourad j.el Ghoul K Omri K Khirouni Laboratory of Physics of Materials and Nanomaterials Applied at Environment (LaPhyMNE) Faculty of Sciences in Gabes Gabes University Imam Mohammad Ibn Saud Islamic University (IMSIU) College of Sciences Department of Physics

Pure ZnO and indium-doped ZnO(In–ZO) nanoparticles with concentrations of In ranging from 0 to 5% are synthesized by a sol–gel processing technique. The structural and optical properties of ZnO and In–ZO nanoparticles are characterized by different techniques. The structural study confirms the presence of hexagonal wurtzite phase and indicates the incorporation of In^(3+) ions at the Zn^(2+) sites. However, the optical study shows a high absorption in the UV range and an important reflectance in the visible range. The optical band gap of In–ZnO sample varies between 3.16 e V and 3.22 e V. The photoluminescence(PL) analysis reveals that two emission peaks appear: one is located at 381 nm corresponding to the near-band-edge(NBE) and the other is observed in the green region. The aim of this work is to study the effect of indium doping on the structural, morphological, and optical properties of ZnO nanoparticles.

关键词： In-doped ZnO nanoparticles sol–gel process structural and optical characterization

Experimental Study on Deoxidization of Bariumand Barium Alloy

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journal of Materials Science & Technology 1999年第5期15卷 400-404页

作者： Shi, YF Chen, BP Fu, j.el Gammal, T Univ Sci & Technol Beijing Met Sch Beijing 100083 Peoples R China Rhein Westfal TH Aachen Inst Eisenhuttenkunde Aachen Germany

Based on the review of latest papers related to the application of barium alloy, the deoxidization effects of barium and barium alloy, and the dynamic characteristics of molten bath have been systematically studied by means of the convection free bath, natural convection bath, air and vacuum induction melting experiments. It was found that both the total oxygen content and soluble oxygen content in molten bath decreased rapidly. The results obtained provided practical and theoretical basis for further synthetic applications of barium alloy in metallurgical industry.

关键词： Barium

Determination and assessment of total mercury levels in local, frozen and canned fish in Lebanon

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journal of Environmental Sciences 2011年第9期23卷 1564-1569页

作者： Pierre j Obeid Bilal el-Khoury joanne Burger Samer Aouad Mira Younis Amal Aoun john Hanna el-Nakat University of Balamand Faculty of SciencesDepartment of Chemistry Nelson Biological Laboratory Division of Life SciencesRutgers University

Fish is an important constituent of the Lebanese ***,very little attention in our area is given to bring awareness regarding the effect of the toxicity of mercury （Hg） mainly through fish *** study aimed to report analytical data on total mercury levels in several fish species for the first time in thirty years and to also made individuals aware of the presence and danger from exposure to mercury through fish *** samples were selected from local Lebanese markets and fisheries and included 94 samples of which were fresh,frozen,processed,and canned *** values were reported as microgram of mercury per gram of fish based on wet *** level of mercury ranged from 0.0190 to 0.5700 μg/g in fresh samples,0.0059 to 0.0665 μg/g in frozen samples,and 0.0305 to 0.1190 μg/g in canned *** data clearly showed that higher levels of mercury were detected in local fresh fish as opposed to other types thus placing consumers at higher risk from mercury ***,the data revealed that Mallifa （yellowstripe barracuda/Sphyraena chrysotaenia）,Sargous （white seabream/Diplodus sargus）,Ghobbos （bogue/Boops boops）,and shrimp （Penaeus sp.） were among the types containing the highest amounts of *** the other hand,processed fish such as fish fillet,fish burger,small shrimp and crab are found to contain lower levels of mercury and are associated with lower exposure risks to *** population should therefore,be aware to consume limited amounts of fresh local fish to minimize exposure to mercury.

关键词： total mercury fish Lebanon

Imaging atomic-scale chemistry from fused multi-modal electron microscopy

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npj Computational Materials 2022年第1期8卷 164-171页

作者： jonathan schwartz Zichao Wendy Di Yi jiang Alyssa j.Fielitz Don-Hyung Ha Sanjaya D.Perera Ismail el Baggari Richard D.Robinson jeffrey A.Fessler Colin Ophus Steve Rozeveld Robert Hovden Department of Materials Science and Engineering University of MichiganAnn ArborMIUSA Mathematics and Computer Science Division Argonne National LaboratoryLemontILUSA Advanced Photon Source Facility Argonne National LaboratoryLemontILUSA Dow Chemical Co. MidlandMIUSA Department of Material Science and Engineering Cornell UniversityIthacaNew YorkUSA School of Integrative Engineering Chung-Ang UniversitySeoulRepublic of Korea Department of Physics Cornell UniversityIthacaNYUSA The Rowland Institute at Harvard CambridgeMAUSA Department of electrical Engineering and Computer Science University of MichiganAnn ArborMIUSA National Center for electron Microscopy Lawrence Berkeley National LaboratoryMolecular FoundryBerkeleyCAUSA Applied Physics Program University of MIchiganAnn ArborMIUnited States

Efforts to map atomic-scale chemistry at low doses with minimal noise using electron microscopes are fundamentally limited by inelastic ***,fused multi-modal electron microscopy offers high signal-to-noise ratio(SNR)recovery of material chemistry at nano-and atomic-resolution by coupling correlated information encoded within both elastic scattering(high-angle annular dark-field(HAADF))and inelastic spectroscopic signals(electron energy loss(EelS)or energy-dispersive x-ray(EDX)).By linking these simultaneously acquired signals,or modalities,the chemical distribution within nanomaterials can be imaged at significantly lower doses with existing detector *** many cases,the dose requirements can be reduced by over one order of *** high SNR recovery of chemistry is tested against simulated and experimental atomic resolution data of heterogeneous nanomaterials.

关键词： materials chemistry fused

On the Set of Grouplikes of a Coring

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Acta Mathematica Sinica,English Series 2012年第1期28卷 195-204页

作者： L.el KAOUTIT j.GóMEZ-TORRECILLAS Departamento de lgebra.Facultad de Educación y Humanidades Universidad de GranadaEl Greco No 10E-51002 CeutaEspaa Departamento de lgebra.Facultad de Ciencias Universidad de GranadaE18071 GranadaEspaa

We focus our attention to the set Gr（ξ） of grouplike elements of a coring ξover a ring A. We do some observations on the actions of the groups U（A） and Aut（ξ~） of units of A and of automorphisms of corings of ξ, respectively, on Gr（ξ）, and on the subset Gal（ξ）of all Galois grouplike elements. Among them, we give conditions on ξ under which Gal（ξ） is a group, in such a way that there is an exact sequence of groups el → U（Ag） → U（A） → Gal（ξ） → el, where Ag is the subalgebra of coinvaxiants for some g ∈ Gal（ξ）.

关键词： Galois corings division ring extensions non-abelian cohomology

Influence of manganese rate on structural, optical and electrochemical properties of CeO_(2) thin films deposited by spray pyrolysis:Supercapacitor applications

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journal of Rare Earths 2022年第10期40卷 1611-1618页

作者： j.Zimou K.Nouneh A.Talbi L.el Gana A.el-Habib R.Hsissou M.Addou Laboratory of Materials Physics and Subatomic Department of PhysicsFaculty of ScienceIbn Tofail UniversityBP 13314000KenitraMoroco Thin Film and Nanomaterial Research Team Faculty of Science and TechiquesAbdelmalek Essadi UniversityTangerMorocco Laboratory of Organic Chemistry Catalysis and EnvironmentFaculty of SciencesIbn Tofail UniversityBP 24214000KenitraMorocco

The present work aimed to investigate the electrochemical properties of ITO substrates in propylene carbonate(PC) with 0.5 mol/L lithium perchlorate(LiClO_(4)) medium in the presence of elaborated thin films of cerium dioxide pure and doped with manganese at varying ***_(1-x)Mn_(x)O_(2)(x=0 wt%,2 wt%,4 wt% and 6 wt%) were successfully deposited by the spray pyrolysis(SP) technique on the glass substrate and ITO at 450℃.The effects of manganese(Mn) doped thin films Ce_(1-x)Mn_(x)O_(2) were studied and investigated by using different analyses namely X-ray diffraction(XRD) analysis,Raman spectroscopy method,UV-Vis spectrophotometer technique,atomic force microscopy(AFM) analysis and electrochemical *** data obtained present a polycrystalline with a face-centred cubic structure of fluorite *** results of undoped and Mn doped thin films show two peaks at 465 and 600 cm^(-1),due to the formation of extrinsic oxygen vacancies by the incorporation of Mn into Ce1-xMnxO_(2) *** dispersive spectroscopy(EDS) data show the presence of Ce,O,and Mn elements in the elaborated *** AFM results reveal that the surface roughness decreases with increasing Mn ***,band gap energy of thin films decreases with increasing in Mn rate due to the formation of defect state between valence and conduction *** storage capacity of the elaborated Ce_(1-x)Mn_(x)O_(2)/ITO/PC+LiClO_(4) electrode reaches a maximum of 1.997 mF in the presence of 6 wt% of Mn.

关键词： Ce1-xMnxO_(2)thin films electrochemical properties ITO substrates XRD/UV-Vis/AFM Band gap energy Storage capacity

Effect of different metal sulfate precursors on structural and catalytic performance of zirconia in dehydration of methanol to dimethyl ether

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燃料化学学报 2018年第1期46卷 67-74页

作者： Abd el-Aziz A.Said Mohamed Abd el-Aal Chemistry Department Faculty of ScienceAssiut University71516 AssiutEgypt

ZrO_2 was treated with 10% SO_4^(2-) from different metal sulfate precursors for methanol dehydration to dimethyl *** the samples exhibited tetragonal phase and no diffraction peaks corresponding to metal sulfates or metal oxides were *** FT-IR results revealed that there were different interactions between sulfate and ZrO_2,and this had a great effect on the surface area of the *** catalytic activity was measured over the catalysts in the temperature range of 100-300 ℃.The results revealed that sulfated zirconia with CuSO_4·5 H_2O and Al_2(SO_4)_3·16 H_2O showed the best catalytic *** maximum yield of DME ≈87% was obtained over CuSZ at a reaction temperature of 275 ℃.Moreover,the catalytic activity of the catalysts was correlated well with their surface acidity that measured by dehydration of isopropanol.

关键词： MSO 4/ZrO2 甲醇脱水 DME

Thermal explosion of a reactive gas mixture at constant pressure for non-uniform and uniform temperature systems

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Defence Technology（防务技术） 2022年第10期18卷 1842-1851页

作者： Saad A.el-Sayed Mechanical Power Engineering Dept.Zagazig University ZagazigAlshrkiaEgypt

In this study,the approximate and exact solutions for the stationary-state of the solids model with neglecting reactant consumption for both non-uniform and uniform temperature systems were applied on gas ignition under a constant pressure *** criticality conditions for a slab,an infinite cylinder,and a sphere are determined and discussed using dimensionless temperatures under constant ambient and surface temperatures for a non-uniform temperature *** solution for a Semenov model with convection heat loss was also *** solution of the Semenov problem for constant volume or density as a solid and constant pressure were *** critical parameterδis calculated and compared with those of Frank-Kamenetskii solution *** validation of the calculated ignition temperatures with other exact solution and experimental results were *** relation between critical parameters form Semenov and *** solution was introduced.

关键词： Thermal explosion Approximate solution Critical conditions Distributed and uniform temperature systems

Artificial Neural Networks Applied to Landslide Susceptibility Mapping in the Northern Area of the Central Rif(Morocco)

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地学前缘 2009年第S1期16卷 64-64页

作者： M.Amharrak j.el khattabi B.Louche L.Asebriy E.Carlier Earth Sciences Department Faculty of SciencesMohamed Premier University Mechanical laboratory of Lille University of Sciences and technologies of Lille Earth Sciences Department Scientific instituteB.P.703Mohammed V-Agdal University

Recently,Artificial Neural Networks(ANNs)have been used for various scientific and engineering applications essentially because they allow the modeling of a process,which starts from the database containing the variables that describe that particular *** have already been applied to the study of landslides in particular,with reference to the indirect determination of the triggering

关键词： Landslide susceptibility statistical approach artificial neural network Central Rif