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Structural,electronic,optical,and magnetic properties of Co-doped Cu2O

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Chinese Physics B 2017年第2期26卷 387-391页

作者： I Djabri T Rezkallah F Chemam Laboratoire de la Physique Appliquee et Theorique Departement des Sciences de la matiere Universite Laarbi tebessi tebessa Algeri

We investigate the magnetic properties of Co-doped Cu_2O. We studied first the electronic and structural properties of Cu_2O using the optimization of the lattice constant which is 4.18 . The calculated gap is found between 0.825 eV and1.5 eV, these values are in good agreement with the experimental results. The Co atoms are inserted in Cu_2O by means of the density functional theory（DFT） using LSDA, LSDA ＋U, and LSDA ＋ MBJ approximations in the WIEN2 k code, based on the supercell model by setting up 12, 24, and 48 atoms in（1×1 × 2）,（1 × 2 × 2）, and（2 × 2×2） supercells respectively with one or two copper atoms being replaced by cobalt atoms. The energy difference between the ferromagnetic and antiferromagnetic coupling of the spins located on the substitute Co has been calculated in order to obtain better insight into the magnetic exchange coupling for this particular compound. The studied compound exhibits stable integer magnetic moments of 2 μBand 4 μBwhen it is doped with 2 atoms of Co. Optical properties have also been worked out. The results obtained in this study demonstrate the importance of the magnetic effect in Cu_2O.

关键词： Cu2O electronic structure magnetic properties optical properties

Pyrolysis of olive residue/low density polyethylene mixture：Part Ⅰ Thermogravimetric kinetics

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燃料化学学报 2008年第6期36卷 672-678页

作者： ABOULKAS A E1 HARFI K El BOUADILI A Laboratoire de Recherche sur la Reactivites des Materiaux et l Optimisation des Procedes ＂REMATOP＂ Departement de chimie Faculte des Sciences Semlalia Universite Cadi Ayyad BP 2390 40001 Marrakech Maroc departement de chimie Faculte polydisciplinaire de Beni-Mellal Universite Sultan Moulay Slimane BP 592 23000 Beni-Mellal Maroc Laboratoire de Chimie Organique et Analytique Departement de chimie Faculte des Sciences et Techniques de Beni-Mellal Universite Sultan Moulay Slimane BP 523 23000 Beni-Mellal Maroc

This paper demonstrates the thermal pyrolysis of olive residue,low density polyethylene(LDPE) and olive residue/LDPE mixture in an inert atmosphere of N2 using thermogravimetric analysis(TGA).Measurements were carried out in the temperature range 300K^973K at heating rates of 2K/min,10K/min,20K/min and 50K/*** on the results obtained,three temperature regimes were selected for studying the non-isothermal kinetics of olive residue/LDPE *** first two were dominated by the olive residue pyrolysis,while the third was linked to the LDPE pyrolysis,which occurred at much higher *** between the experimental and calculated TG/DTG profiles were considered as a measurement of the extent of interactions occurring on *** maximum degradation temperatures of each component in the mixture were higher than those the individual components;thus an increase in thermal stability was *** kinetic parameters associated with thermal degradation were determined using Friedman isoconversional method.

关键词：高温分解反应低密度聚乙烯动力学 LDPE

Univoque graphs for non-integer base expansions

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Science China Mathematics 2021年第12期64卷 2667-2702页

作者： Yuru Zou Jiachang Li Jian Lu Vilmos Komornik College of Mathematics and Statistics Shenzhen UniversityShenzhen 518060China departement de Mathematique Universite de StrasbourgStrasbourg 67084France

Unique expansions in non-integer bases have been investigated in many papers during the last thirty *** are often conveniently generated by labeled directed *** give a precise description of the set of sequences generated by these *** provides a geometric explanation of many former abstract results in this *** results are illustrated by many examples.

关键词： expansions in non-integer bases univoque graph topological dynamics

Ab initio study of structural,electronic,thermo-elastic and optical properties of Pt3Zr intermetallic compound

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Chinese Physics B 2020年第4期29卷 405-414页

作者： Wahiba Metiri Khaled Cheikh departement de Physique Facultedes SciencesUniversite 20 aout 1955-Skikda BP 26Route El-Hadaiek21000 SkikdaAlgeria departement de Technologie Facultede TechnologieUniversite 20 aout 1955-Skikda BP 26Route El-Hadaiek21000 SkikdaAlgeria

Structural,elastic,electronic and optical properties of the Pt3Zr intermetallic compound are investigated using first principles calculations based on the density functional theory(DFT)within the generalized gradient approximation(GGA)and the local density approximation(LDA).The Pt3Zr compound is predicted to be of cubic L12 and hexagonal D024 *** calculated equilibrium ground-state properties(lattice parameters a and c,bulk modulus B and its pressure derivative B',formation enthalpy ΔH)of the Pt3Zr compound,for both cubic and hexagonal phases,show good agreement with the experimental results and other theoretical *** constants(C11,C12,C13,C33,C44,and C55)are *** predicted elastic properties such as Young's modulus E and shear modulus GH,Poisson ratioν,anisotropic ratio A,Kleinman parameter ξ,Cauchy pressure(C12-C44),ratios B/C44 and B/G,and Vickers hardness Hv indicate the stiffness,hardness and ductility of the *** characteristic parameters such as debye temperature θD and melting temperature Tm are *** properties such as density of states(DOS)and electronic specific heat γ are also *** calculated results reveal that the Fermi level is on the psedogap for the D024 structure and on the antibonding side for the L12 *** optical property functions(real partε1(ω)and imaginary part ε2(ω)of dielectric function),optical conductivity σ(ω),refraction index n(ω),reflectivity R(ω),absorption α(ω)and extinction coefficients k(ω)and loss function L(ω)are also investigated for the first time for Pt3Zr in a large gamme of energy from 0 to 70 eV.

关键词： density functional theory intermetallic density of states L12 D024 optical properties

Data-driven drug repositioning using olfactory omics profiles:challenges and perspectives in neurodegeneration

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Neural Regeneration Research 2025年第7期20卷 1997-1998页

作者： Paz Cartas-Cejudo Adriana Cortés Mercedes Lachén-Montes Elena Anaya-Cubero Joaquín Fernández-Irigoyen Enrique Santamaría Clinical Neuroproteomics Unit Proteomics PlatformNavarrabiomedHospitalario Universitario de Navarra(HUN)Universidad Pública de Navarra(UPNA)IdiSNANavarra Institute for Health ResearchPamplonaSpain

Data-driven drug repositioning using olfactory omics profiles-challenges and perspectives in neurodegeneration:Neurodegenerative diseases are characterized by progressive degeneration and loss of neuronal function in the central nervous *** diseases are often characterized as proteinopathies,which are disorders primarily driven by the aggregation or misfolding of specific amyloid proteins within cells,leading to their dysfunction and eventual *** the gain-of-function hypothesis related to the aggregation of these proteins,recently,an alternative hypothesis regarding the loss-of-function of the soluble monomeric proteins during the process of aggregation into amyloids is gaining *** last event is called proteinopenia and refers to conditions characterized by a deficiency or decrease in the levels of specific soluble proteins in the body(Ezzat et al.,2023).It has been demonstrated that levels of soluble proteins involved in neurodegenerative diseases are decreased.

关键词： diseases drug amyloid

Olfactory receptors in neural regeneration in the central nervous system

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Neural Regeneration Research 2025年第9期20卷 2480-2494页

作者： Rafael Franco Claudia Garrigós Toni Capó Joan Serrano-Marín Rafael Rivas-Santisteban Jaume Lillo Molecular Neurobiology Laboratory Department of Biochemistry and Molecular BiomedicineFacultat de BiologiaUniversitat de BarcelonaBarcelonaSpain CiberNed Network Center for Biomedical Research in Neurodegenerative Diseases Spanish National Health Institute Carlos ⅢMadridSpain School of Chemistry Universitat de BarcelonaBarcelonaSpain department of Biochemistry and Physiology School of Pharmacy and Food SciencesUniversitat de BarcelonaBarcelonaSpain Laboratory of Computational Medicine Biostatistics UnitFaculty of MedicineAutonomous University of BarcelonaCampus BellaterraBarcelonaSpain

Olfactory receptors are crucial for detecting odors and play a vital role in our sense of smell,influencing behaviors from food choices to emotional *** receptors also contribute to our perception of flavor and have potential applications in medical diagnostics and environmental *** ability of the olfactory system to regenerate its sensory neurons provides a unique model to study neural regeneration,a phenomenon largely absent in the central nervous *** gained from how olfactory neurons continuously replace themselves and reestablish functional connections can provide strategies to promote similar regenerative processes in the central nervous system,where damage often results in permanent *** the molecular and cellular mechanisms underpinning olfactory neuron regeneration could pave the way for developing therapeutic approaches to treat spinal co rd injuries and neurodegenerative diseases like Alzheimer's *** ctory receptors are found in almost any cell of eve ry orga n/tissue of the mammalian *** ectopic expression provides insights into the chemical structures that can activate olfactory *** addition to odors,olfactory receptors in ectopic expression may respond to endogenous compounds and molecules produced by mucosal colonizing *** analysis of the function of olfactory receptors in ectopic expression provides valuable information on the signaling pathway engaged upon receptor activation and the receptor's role in proliferation and cell differentiation *** review explo res the ectopic expression of olfa ctory receptors and the role they may play in neural regeneration within the central nervous system,with particular attention to compounds that can activate these receptors to initiate regenerative *** suggests that olfactory receptors could serve as potential therapeutic targets for enhancing neural repair and recovery following central nervous syste

关键词： adenosine receptors adrenergic receptors ectopic expression G proteincoupled receptors glia neurons

Field-induced phase transitions in chiral smectic liquid crystals studied by the constant current method

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Chinese Physics B 2016年第5期25卷 373-379页

作者： H Dhaouadi R Zgueb O Riahi F Trabelsi T Othman departement de physiqu Faculte des Sciences de Tunis Laboratoire de physique de la matiere molle et de modelisation electromagnetique (LP3ME) Universite Tunis Elmanar Campus universitaire 2092 Tunis Tunisia

In ferroelectric liquid crystals, phase transitions can be induced by an electric field. The current constant method allows these transition to be quickly localized and thus the（E, T） phase diagram of the studied product can be *** this work, we make a slight modification to the measurement principles based on this method. This modification allows the characteristic parameters of ferroelectric liquid crystal to be quantitatively measured. The use of a current square signal highlights a phenomenon of ferroelectric hysteresis with remnant polarization at null field, which points out an effect of memory in this compound.

关键词： chiral smectic liquid crystal constant current method ferroelectric polarization dielectric permittivity

First-principles study and electronic structures of Mn-doped ultrathin ZnO nanofilms

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Chinese Physics B 2012年第10期21卷 362-368页

作者： E.Salmani A.Benyoussef H.Ez-Zahraouy E.H.Saidi O.Mounkachi LMPHE(URAC 12) Departement de PhysiqueFacult'e des SciencesUniversit'e Mohammed V-AgdalRabatMorocco LPHE Departement de PhysiqueFacult'e des SciencesUniversit'e Mohammed V-AgdalRabatMorocco Institute of Nanomaterials and Nanotechnology MAScIRRabatMorocco

The first-principles density functional calculation is used to investigate the electronic structures and magnetic properties of Mn-doped and N-co-doped ZnO *** band structure calculation shows that the band gaps of ZnO films with 2,4,and 6 layers are larger than the band gap of the bulk with wurtzite structure and decrease with the increase of film ***,the four-layer ZnO nanofilms exhibit ferromagnetic phases for Mn concentrations less than 24% and 12% for Mn-doping performed in the whole layers and two layers of the film respectively,while they exhibit spin glass phases for higher Mn *** is also found,on the one hand,that the spin glass phase turns into the ferromagnetic one,with the substitution of nitrogen atoms for oxygen atoms,for nitrogen concentrations higher than 16% and 5% for Mn-doping performed in the whole layers and two layers of the film *** the other hand,the spin-glass state is more stable for ZnO bulk containing 5% of Mn impurities,while the ferromagnetic phase is stable by introducing the p-type carriers into the bulk ***,it is shown that using the effective field theory for ferromagnetic system,the Curie temperature is close to the room temperature for the undamped Ruderman-Kittel-Kasuya-Yoshida（RKKY） interaction.

关键词： ultra thin film ZnO ab initio electronic structure magnetic properties effective field theory

Chemical Indicator of Spinel During Partial Melting and Subsolidus Equilibration of Mantle Peridotite:Experimental Study and Application to Natural Rocks

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Acta Geologica Sinica(English Edition) 1995年第4期69卷 420-435页

作者： Jacques Kornprobst Daniel Vielzeuf departement de Geologie et Mineralogie University Blaise Pascal63038 Clermont-Ferrand FranceDepartement de Geologie et Mineralogie University Blaise Pascal63038 Clermont-Ferrand France

Systematic experimental studies on partial melting and subsolidus equilibration of three reconstituted spinel-peridotites have been carried out at temperatures ranging from 1000 to 1380℃ and pressures of 1.0 and 1.5 GPa. The results shows (1) during partial melting, Mg# [=Mg/(Mg+Fe)]and Cr# [=Cr/(Cr-Al)]of spinel increase with an increase in degrees of melting) (2) during subsolidus equilibration, with increasing temperatures, Mg# of spinel increases but Cr# of spinel remains almost unchanged in dunite and increases slightly in Iherzolite and harzburgite. The negative and quasi-linear Mg# -Cr# correlation of spinel represents an isotherm of total non-equilibrium. The same results have been obtained by means of mathematical modelling. It is also proved by Mg# -Cr# correlation of spinel in natural peridotites. As a result of the spinel subsolidus equilibration, only variation of Cr# of spinel is limited, and then Cr# of spinel can be used to estimate the relative degree of melting undergone by host rocks. The bigger Cr# of spinel is, the higher the degree of melting will be. By contrast, during crystallization magma, Mg# and Cr# of spinel decrease with decreasing temperatures. Likewise, Cr# of spinel in basalts may be used to indicate the feature of Cr2O3/Al2O3 of magma, and the compositional zoning of spinel may be used to study the evolution of magma (cooling rate and contamination).

关键词： peridotite spinel partial melfing subsolidus equilibration experimental study and application