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Extraordinary piezoelectric effect induced in two-dimensional rare earth monochalcogenides via reducing system dimensionality

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Journal of Materiomics 2023年第1期9卷 72-81页

作者： Neveen I.Atallah Maged El-Kemary Fabien Pascale Khaled E.El-Kelany Institute of Nanoscience and Nanotechnology Kafrelsheikh University33516Kafr el-skiekhEgypt Universite de Lorraine-Nancy CNRSLaboratoire de Physique et Chimie TheoriquesUMR 7019Vandoeuvre-les-NancyFrance

Piezoelectricity is pivotal for applications in micro/nanoelectromechanical systems(MEMS/NEMS).Inducing such a property in 2D systems via the reduction of the dimensionality of their corresponding 3D bulk is here *** on DFT theory and Gaussian-type-localized basis sets,the structural,electronic,mechanical,and piezoelectric properties of both 3D and 2D rare earth monochalcogenides RmX(Rm=Tm,Yb,Lu,and X=S,Se,Te)are investigated using the CRYSTAL *** intriguingly,the 2D LuX compounds display a buckled structure,where the Lu and X atoms protrude from the monolayer surface leading to an additional out-of-plane piezoelectric effect;(e_(31)=2104.84,1770.28,1689.79 pC/m,and d31=56.37,49.76,and 147.90 pm/V for LuS,LuSe,and LuTe,respectively).Such piezoelectric response is two orders of magnitude larger than the one of recently reported 2D ferroelectric MXenes,and is nearly thirty times larger than the commonly used AlN and GaN bulk ***,the reduced elastic constants obtained,when compared to other 2D materials,confirm the flexibility and softness of the considered 2D systems.

关键词： 2D materials Rare earth monochalcogenides DFT Gaussian basis CRYSTAL code Piezoelectric effect MEMS/NEMS

A quantum cascade laser infrared spectrometer for CO_2 stable isotope analysis：Field implementation at a hydrocarbon contaminated site under bio-remediation

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Journal of Environmental Sciences 2016年第2期28卷 60-74页

作者： Christophe Guimbaud Cécile Noel Michel Chartier Valéry Catoire Michaela Blessing Jean Christophe Gourry Claude Robert laboratoire de Physique et de chimie de l'Environnement et de l'Espace (LPC2E) CNRS et Universite d'Orleans (UMR 7328)45071 Orleans cedex 2 France Bureau de Recherches Geologiques et Minieres (BRGM) 45060 Orleans cedex 2 France

Real-time methods to monitor stable isotope ratios of CO_2 are needed to identify biogeochemical origins of CO_2 emissions from the soil–air interface. An isotope ratio infra-red spectrometer（IRIS） has been developed to measure CO_2 mixing ratio with δ~13C isotopic signature, in addition to mixing ratios of other greenhouse gases（CH_4, N2_O）. The original aspects of the instrument as well as its precision and accuracy for the determination of the isotopic signature δ~13C of CO_2 are discussed. A first application to biodegradation of hydrocarbons is presented, tested on a hydrocarbon contaminated site under aerobic bio-treatment. CO_2 flux measurements using closed chamber method is combined with the determination of the isotopic signature δ~13C of the CO_2 emission to propose a non-intrusive method to monitor in situ biodegradation of hydrocarbons. In the contaminated area, high CO_2 emissions have been measured with an isotopic signature δ~13C suggesting that CO_2 comes from petroleum hydrocarbon *** first field implementation shows that rapid and accurate measurement of isotopic signature of CO_2 emissions is particularly useful in assessing the contribution of contaminant degradation to the measured CO_2 efflux and is promising as a monitoring tool for aerobic bio-treatment.

关键词： Isotope ratio infrared spectrometry Isotopic signature δ^(13)C of CO_2 Biodegradation monitoring Hydrocarbons BTEX

Diffusion analysis and modeling of kinetic behavior for treatment of brine water using electrodialysis process

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Water Science and Engineering 2021年第1期14卷 36-45页

作者： Fadi Alakhras Emna Selmane Bel Hadj Hmida Ioannis Anastopoulos Zina Trabelsi Walid Mabrouk Noureddine Ouerfelli Jean François Fauvarque department of Chemistry College of ScienceImam Abdulrahman Bin Faisal UniversityDammam 31441Saudi Arabia laboratoire de chimie Analytique et Electrochimie Departement de ChimieUniversite de Tunis El ManarTunis 2092Tunisia department of Electronic Engineering School of EngineeringHellenic Mediterranean UniversityChania 73100Greece laboratoire de Biophysique et Technologies Medicales Universite de Tunis El ManarTunis 1006Tunisia Laboratory of Water Membranes and Environmental BiotechnologySoliman 8020Tunisia laboratoire d’Electrochimie Industrielle Conservatoire National des Arts et Metiers(CNAM)de ParisParis 75003France

In this study,the removal of monovalent and divalent cations,Nat,Kt,Mg2t,and Ca2t,in a diluted solution from Chott-El Jerid Lake,Tunisia,was investigated with the electrodialysis *** process was tested using two cation-exchange membranes:sulfonated polyether sulfone cross-linked with 10%hexamethylenediamine(HEXCl)and sulfonated polyether sulfone grafted with octylamine(S-PESOS).The commercially available membrane Nafion®was used for *** results showed that Nafion®and S-PESOS membranes had similar removal behaviors,and the investigated cations were ranked in the following descending order in terms of their demineralization rates:Nat>Ca2t>Mg2t>*** cations were more effectively removed by HEXCl than by monovalent *** plots based on the WebereMorris model showed a strong *** reveals that intra-particle diffusion was not the removal rate-determining step,and the removal process was controlled by two or more concurrent *** Boyd plots did not pass through their origin,and the sole controlling step was determined by film-diffusion resistance,especially after a long period of ***,a semi-empirical model was established to simulate the temporal variation of the treatment process,and the physical significance and values of model parameters were compared for the three *** findings of this study indicate that HEXCl and S-PESOS membranes can be efficiently utilized for water softening,especially when effluents are highly loaded with calcium and magnesium ions.

关键词： Ionic exchange membrane Electrodialysis Brine water Boyd diffusion model Intraparticle diffusion

A fully bio-sourced adsorbent of heavy metals in water fabricated by immobilization of quinine on cellulose paper

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Journal of Environmental Sciences 2019年第10期31卷 174-183页

作者： Ehu C.Aka Medy C.Nongbe Tchirioua Ekou Lynda Ekou Vincent Coeffard Francois-Xavier Felpin Universite de Nantes CNRS UMR 6230CEISAM2 rue de la Houssinière44322 Nantes Cedex 3France Universite Nangui Abrogoua Laboratoire de Thermodynamique et de Physico-Chimie du Milieu02 BP 801 Abidjan 02Cote d'lvoire

The fabrication of a fully bio-sourced adsorbent of Cd(Ⅱ)by covalent immobilization of quinine on cellulose paper is *** double bond of commercially available quinine was converted to a terminal alkyne function which was reacted with cellulose paper,chemically modified with azide functions,through a 1,3-dipolar cycloaddition,leading to *** adsorption efficiency of Cell-Quin was investigated to determine the optimal pH,contact time and dose of adsorbent,ultimately leading to high levels of *** mechanism of adsorption of Cell-Quin was deeply rationalized through kinetic experiments and isotherm *** also showed that Cell-Quin could adsorb other heavy metals such as Cu(Ⅱ),Pb(Ⅱ),Ni(Ⅱ)and Zn(Ⅱ).

关键词： Cellulose paper Quinine Heavy metal removal Adsorbent

Effects of acid treatments on Moroccan Tarfaya oil shale and pyrolysis of oil shale and their kerogen

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燃料化学学报 2009年第6期37卷 659-667页

作者： ABOULKAS A El HARFI K laboratoire de Recherche sur la Reactivites des Materiaux et IOptimisation des Procedes 《REMATOP》 Departement de chimie Faculte des Sciences Semlalia Universite Cadi Ayyad BP 2390 40001 Marrakech Maroc laboratoire lnterdisciplinaire de Recherche en Sciences et Techniques Faculte polydisciplinaire de Beni-Mellal Universite Sultan Moulay Slimane BP 592 23000 Beni-Mellal Maroc

In this study,the kerogen of oil shale from Moroccan Tarfaya deposits was isolated and the changes in the initial organic matter during the removal of the mineral matrix were *** extraction of the oil shale increases the intensity of the peaks in the X-ray *** spectra and X-ray diffractograms reveal the presence of mineral,calcite,quartz,kaolinite,and pyrite in the mineral matrix of the oil *** and hydrofluoric acids dissolution do not alter the organic *** nonisothermal weight loss measurements indicate that thermal decomposition of the isolated kerogen can be described by first-order reaction.A single kinetic expression is valid over the temperature range of kerogen pyrolysis between 433K and ***,the results indicate that the removal of mineral matter causes a decrease in the activation energies of the pyrolysis reactions of oil shale.

关键词：页岩矿物方解石氢氟酸

盐酸溶液中钢铁腐蚀的绿色缓蚀剂柠檬油精(英文)

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物理化学学报 2009年第7期25卷 1254-1258页

作者： CHAIEB E. BOUYANZER A. HAMMOUTI B. BERRABAH M. laboratoire de chimie Appliquée et Environnement Faculté des Sciences

The inhibition of steel corrosion in hydrochloric acid solutions by limonene, which was extracted from citrus and orange fruit, was studied using measurements of mass loss, electrochemical polarisation and electrochemical impedance spectroscopy (EIS) methods. Naturally, the substance reduced the rate of corrosion. The linearity of the cathodic curves for all concentrations indicated that the law of Tafel was followed. The effectiveness of inhibition increased with the increase in concentration of limonene and this exceeded 72% at 0.220 g·L-1. The inhibition efficiency is temperature independent in the temperature range of 298-328 K. Adsorption of the substance on the surface of steel obeys the Frumkin isotherm model.

关键词：钢腐蚀金属氯化氢 EIS

Photoresponse and H2 gas sensing properties of highly oriented Al and Al/Sb doped ZnO thin films

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Progress in Natural Science:Materials International 2013年第6期23卷 519-523页

作者： Hannane Benelmadjat Boubekeur Boudine Aissa Keffous Noureddine Gabouze laboratoire de Physico-chimie des Semi-Conducteurs Departement de PhysiqueFaculte des Sciences ExactesUniversite Mentouri-Route Ain Elbey laboratoire de Cristallographie Departement de PhysiqueFaculte des Sciences ExactesUniversite Mentouri-Route Ain Elbey Silicon Technology development Unit

ZnO:Al and ZnO:Al/Sb thin films have been prepared and *** thin films were deposited on Si substrates by the sol-gel *** structural,optical and electrical properties of ZnO films have been investigated by spectrophotometry,ellipsometry,X-ray diffraction and current-voltage *** is found that the films exhibit wurtzite structure with a highly c-axis orientation perpendicular to the surface of the substrate,a high reflectivity in the infrared region and a response to ***,it has been found that Si/（ZnO:Al/Sb）/Al photodiode is promising in photoconduction device while Si/（ZnO:Al）/Al can be used as gas sensor responding to the low H2concentrations.

关键词： Zinc oxide Co-doping Thin films Gas sensing Photoresponse

(E) Enol ethers from the stereoselective reduction of α-alkoxy-β-ketophosphonates and Wittig type reaction

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Science China Chemistry 2010年第9期53卷 1937-1945页

作者： DAYOUB Wissam DOUTHEAU Alain laboratoire de Catalyse et Synthèse Organique Institut de Chimie et Biochimie Moléculaires et Supramoléculaires(ICBMS)CNRSUMR5246Université Lyon 1 Institut National des Sciences Appliquées de Lyon Laboratoire de Chimie Organique et BioorganiqueICBMS UMR 5246 CNRS Université Lyon 1 INSA Lyon

When α-alkoxy-β-ketophosphonates,prepared by the Rh(Ⅱ) mediated insertion reaction of α-diazo-β-ketophosphonates into the OH bond of primary alcohols,were reduced either by NaBH4 in the presence of CaCl2 or by DIBAL,they respectively gave the corresponding anti or syn stereomeric hydroxyphosphonates with pronounced to complete *** to the action of potassium tert-butoxyde,syn isomers led to the corresponding pure(E) enol ethers in moderate to good *** the same conditions anti isomers led to a mixture of(Z) and(E) enol ethers in rather poor *** sequence was applied to the preparation of some allyl-vinyl ethers with a(E) configuration for the vinylic double bond.

关键词： α-alkoxy-β-ketophosphonates reduction insertion rhodiocarbenoids Wittig-Wadsworth-Emmons enol ethers

CLASSICAL HEISENBERG MAGNETIC CHAINS SHOWING CATIONIC SITE OCCUPATIONS CORRELATIONS

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Chinese Physics Letters 1989年第11期6卷 518-521页

作者： R.Georges XU Qiang laboratoire de chimie du Solide Universitéde Bordeaux I33405TalenceCEDEX Kamerling Onnes Laboratorium Nieuwsteeg 18P.O.Box 95062300RALeydenThe Netherlands

We propose a model for calculating the magnetic susceptibility of classical Heisenberg chains,showing nearest neighbor correlated cationic *** result formally looks like expressions obtained for random chains where the neighboring cationic species are not *** the present result the intervening scalar parameters are replaced,by vector and matricial expressions.

关键词： chains cationic CLASS