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Chinese Physics B 2015年第10期24卷 359-365页

作者： Youcef Megrouss Nadia Benhalima Rawia Bahoussi Nouredine Boukabcha Abdelkader Chouaih Fodil Hamzaoui laboratoire de Technologie et Proprietedu Solide(LTPS) University of Mostaganem

This work is devoted to the experimental determination of the electrostatic properties of the molecular 4-methyl-7-（salicylidene amino） coumarin（C17H13NC3） using high resolution x-ray diffraction data. The experimental results are compared with those obtained theoretically from calculation type ab initio. The experimental investigation is carried out using the molecular electron charge density distribution based on the multipolar model of Hansen and Coppens. However the theoretical calculations are conducted by using the molecular orbital B3 LYP method and the Hartree-Fock（HF） approximation with the basis set 6-31G（d,p） implemented in the Gaussian program. In addition to the structural analysis,the thermal agitation is also analyzed in terms of rigid blocks to ensure a better precision of the results. Subsequently, the electrostatic atomic and molecular properties such as the net charges, the molecular dipolar moment to highlight the nature of charge transfer existing within the molecule studied are derived. Moreover, the obtained electrostatic potential enables the localization of the electropositive and the electronegative parts of the investigated molecule. The present work reports in detail the obtained electrostatic properties of this biologically important molecule.

关键词： electron charge density electrostatic potential molecular dipole moment and x-ray diffraction

Purity-dependent Lorenz number,electron hydrodynamics and electron-phonon coupling in WTe_(2)

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Science China(Physics,Mechanics & Astronomy) 2024年第8期67卷 153-158页

作者： Wei Xie Feng Yang Liangcai Xu Xiaokang Li Zengwei Zhu Kamran Behnia Wuhan National High Magnetic Field Center and School of Physics Huazhong University of Science and TechnologyWuhan 430074China laboratoire de Physique et d’etude des matériaux(ESPCI-CNRS-Sorbonne Université)PSL University Paris 75005France

We present a study of electrical and thermal transport in Weyl semimetal WTe_(2)down to 0.3 *** Wiedemann-Franz law holds below 2 K and a downward deviation starts *** deviation is more pronounced in cleaner samples,as expected in the hydrodynamic picture of electronic transport,where a fraction of electron-electron collisions conserve *** are the dominant heat carriers and their mean-free-path does not display a Knudsen *** is presumably a consequence of weak anharmonicity,as indicated by the temperature dependence of the specific *** momentum exchange between phonons and electrons leads to quantum oscillations of the phononic thermal ***-Grüneisen picture of electron-phonon scattering breaks down at low temperature when Umklapp ph-ph collisions cease to be a sink for electronic flow of *** with semi-metallic Sb shows that normal ph-ph collisions are amplified by *** both semimetals,at cryogenic temperature,e-ph collisions degrade the phononic flow of energy but not the electronic flow of momentum.

关键词： thermal conductivity Wiedemann-Franz law electron hydrodynamics electron-phonon coupling

Morphology and Photoelectrochemical Characterization of MEH-PPV/PCBM Composite Film Doped with TiO_2 Nanoparticles

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Acta Metallurgica Sinica(English Letters) 2013年第4期26卷 373-377页

作者： Farid Habelhames Zerguine Wided Leila Lamiri Belkacem Nessark Hassina derbal-Habak laboratoire d'lectrochimie et matriaux(LEM) Facult de Technologie.Dpartement de gnie des Universit Ferhat Abbas Stif 119000Algrie ECOLE POLYTECHNIQUE LPICM LaboratoryORGATECH Team Route de Saclay ParisFrance

Poly[2-methoxy-5-（20-ethylhexyloxy）-io-phenylenevinylene] （MEH-PPV）, [6,6]-phenyl-C61-butyric acid methyl ester （PCBM） and titanium dioxide （TiO2） nanoparticles （n-type） were dissolved, mixed and deposited by physical methods （spin-coating） on indium tin-oxide （ITO） substrate. The incorporation of the titanium dioxide nanoparticles changed the morphology and increased the roughness of polymers film （MEH-PPV/PCBM）, and the photocurrent density of the composite （MEH-PPV/PCBM ＋n-TiO2） was higher than that of single MEH- PPV/PCBM film. The study showed that the presence of n-TiO2 particles in the polymeric film improves the photoelectrochemical properties of M EH-PPV/PCBM composite.

关键词： Photocurrent density Electrochemical property Hybrid coating Conducting polymer Titanium dioxide Organic nanostructures

Monitoring of pesticides residues in fruits and vegetables:Method optimization and application

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Food Bioscience 2022年第6期50卷 1812-1823页

作者： Wissam Sahyoun Sopheak Net Moomen Baroudi Baghdad Ouddane Univ.Lille CNRSUMR 8516 - LASIRELaboratoire Avancé de Spectroscopie pour les Interactionsla Réactivité et l’EnvironnementF-59000LilleFrance Université Libanaise Faculté de santé publique section IIILaboratoire des Sciences de l’Eau et de l’Environnement (L.S.E.E)TripoliLebanon

QuEChERS CEN Standard Method EN 15662 method was used with some modification for better efficiency of the extraction and purification of pesticides residues in fruits and vegetables *** extracts were analyzed by GC–MS/MS for 14 multiclass pesticides in fruits and *** method was validated with real matrix with good efficiency ranging from 73 to 124%and the LODs and LOQs were 0.001–0.4μg kg−1 and 0.002–1.0μg kg−1 *** method was applied to investigate the level of pesticide residues in 58 fruits and vegetables and with four condition:with and without washing,with and without *** condition is to simulate the condition how people consume fruits and vegetables and to find out if with the sample act,the level of pesticides can be *** studied confirmed the absences or lower concentration of pesticides in organic fruits and vegetables compared to which originated from intensive agricultural where pesticides are widespread *** results were then compared to the maximum residue limits for each pesticides and in each *** results allow to conclude that washing or removing skin should be one of the solution to reduced health impact related to pesticide in fruits and vegetables.

关键词： d-SPE QuEChERS extraction GC-MS/MS Pesticides Fruits Vegetables

热喷涂FeAl涂层中纳米晶结构的XRD分析

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金属学报 2005年第10期41卷 1013-1019页

作者：嵇罡 T.Grosdidier 高泰瑞 A.Tidu 邹建新董闯 laboratoire d' etudes et de Recherches sur les matériaux les Procédés et les Surfaces EA 3316 Université de Technologie de Belfort-Montbéliard Site de Sevenans laboratoire d' etude des Textures et Application aux matériaux laboratoire d'etude des Textures et Application aux matériaux 大连理工大学三束材料改性国家重点实验室大连116024

利用超音速火焰喷涂(HVOF)和大气等离子喷涂(APS)工艺分别喷涂了雾化(微米结构的)以及球磨(纳米结构的)Fe-Al粉末制备了不同结构的涂层.两种原料粉末和喷涂工艺均引起涂层的XRD峰异常宽化.由宽化峰给出的晶粒尺寸与TEM测出的晶粒尺寸有... 详细信息

利用超音速火焰喷涂(HVOF)和大气等离子喷涂(APS)工艺分别喷涂了雾化(微米结构的)以及球磨(纳米结构的)Fe-Al粉末制备了不同结构的涂层.两种原料粉末和喷涂工艺均引起涂层的XRD峰异常宽化.由宽化峰给出的晶粒尺寸与TEM测出的晶粒尺寸有较大的差异.结合SEM、电子探针以及TEM的测试结果,同时考虑到涂层中形成的结构缺陷以及化学成分的不均匀性,证实异常宽化来自喷涂过程中由于Al的耗损导致的FeAl相中Al的成分不均匀分布.

关键词： FleAl基涂层热喷涂纳米晶结构 X射线衍射

Contamination,Fractionation and Availability of Metals in Urban Soils in the Vicinity of Former Lead and Zinc Smelters,France

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Pedosphere 2013年第2期23卷 143-159页

作者： C.WATERLOT G.BIDAR A.PELFRNE H.ROUSSEL H.FOURRIER F.DOUAY Université Lille Nord de France Groupe ISA Equipe Sols et Environnement Laboratoire Génie Civil et géoEnvironnement (LGCgE) Lille Nord de France (EA 4515) Département des Sites et Sols Pollués Agence de I'Environment et de la Matrise de I'Energie (ADEME)

Soil contamination by metals from anthropogenic activities （e.g., mining and smelting） is a major concern for the environment and human health. Environmental availability of cadmium （Cd）, lead （Pb）, zinc （Zn）, copper （Cu）, and indium （In） in 27 urban soils located around two former Pb and Zn smelters in Northern France were studied by analysing the chemical forms of these metals and evaluating their phytoavailability. These metals were determined using flame or electrothermal absorption atomic spectrometry （FAAS or etAAS）, depending on their concentration levels. After optimisation of the etAAS method, characteristic mass of In in water and aqua regia were 9.9 and 18 pg, respectively, showing the high sensitivity of the analytical procedure. Metal partitioning was conducted using a four-step sequential extraction procedure. The results showed that Cd and Zn were mainly in the acid-extractable and reducible forms in the urban soils studied. In contrast, Pb and In were largely in the reducible fraction. However, in some samples, the amount of In extracted in the residual or exchangeable fraction was higher than that in the reducible fraction. Copper was mainly found in the reducible and residual fractions. A pot experiment was conducted in a glasshouse with seven soils （six contaminated and one uncontaminated） and two plant species, ryegrass and lettuce. The results showed transfer of metals from the contaminated soils to the shoots of ryegrass and the edible part of lettuce. The metal bioconcentration factor was in the order of Cd 〉〉 Cu 〉 In 〉 Zn 〉〉 Pb for lettuce leaves, whereas for ryegrass shoots, three orders were found, Cd 〉 Zn 〉 Cu 〉〉 In 〉 Pb, Cd 〉〉 In 〉 Zn 〉 Cu 〉〉Pb, and Zn 〉 Cd 〉 Cu 〉 In 〉〉 Pb, depending on the physico-chemical properties of the soils, such as pH, cation exchange capacity, carbonates, and organic matter. It was established that the metal toxicity was related to the contamination levels and the physico-chemical properties, including pH, organi

关键词： bioconcentration factor environmental availability metal toxicity sequential extraction soil physico-chemical property

Nickel ferrite spinel as catalyst precursor in the dry reforming of methane:Synthesis,characterization and catalytic properties

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Journal of Natural Gas Chemistry 2012年第5期21卷 595-604页

作者： Rafik Benrabaa Hamza Boukhlouf Axel Lfberg Annick Rubbens Rose-Nelle Vannier Elisabeth Bordes-Richard Akila Barama laboratoire de matériaux Catalytiques & Catalyse en Chimie Organique Faculté de ChimieUSTHBBP32 El Alia16111 Bab EzzouarAlgerAlgérie Unité de Catalyse et de Chimie du Solide UMR CNRS 8181Ecole Nationale Supérieure de Chimie de LilleUniversitédes Sciences et Technologies de LilleCité Scientif ique59655 Villeneuve d'AscqFrance

Dry reforming of methane by CO2 using nickel ferrite as precursor of catalysts was *** ferrite crystalline particles were prepared by coprecipitation of nitrates with NaOH or ammonia followed by calcination,or by hydrothermal synthesis without calcination *** textural and structural properties were determined by a number of analysis methods,including X-ray diffraction （XRD）,Raman spectroscopy and X-ray photoelectron spectroscopy （XPS）,among which X-ray diffraction （XRD） was at room and variable *** synthesized oxides showed the presence of micro or nanoparticles of NiFe2O4 inverse spinel,but Fe2O3 （hematite） was also present when ammonia was used for *** reducibility by hydrogen was studied by temperature-programmed reduction （TPR） and in situ XRD,which showed the influence of the preparation *** surface area （Bet）,particle size （Rietveld refinement）,as well as surface Ni/Fe atomic ratio （XPS） and the behavior upon reduction varied according to the synthesis *** catalytic reactivity was investigated using isopropanol decomposition to determine the acid/base *** catalytic performance of methane reforming with CO2 was measured with and without the pre-treatment of catalysts under H2 in 650-800 C *** catalytic conversions of methane and CO2 were quite low but they increased when the catalysts were pre-reduced.A significant contribution of reverse water gas shift reaction accounted for the low values of H2 /CO *** coking was observed as shown by the reoxidation step performed after the catalytic *** possible formation of nickel-iron alloy observed during the study of reducibility by hydrogen was invoked to account for the catalytic behavior.

关键词： dry reforming of methane NiFe2O4 spinel hydrothermal synthesis coprecipitation isopropanol decomposition

Feasibility Study of the Synthesis of Isocyanate-Free Polyurethanes from Catechin

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Journal of Renewable materials 2022年第5期10卷 1175-1184页

作者： Wissem Sahmim Febrina dellarose Boer Hubert Chapuis Firmin Obounou-Akong Antonio Pizzi Philippe Gérardin Christine Gérardin-Charbonnier Facultédes Sciences et Technologies Laboratoire d’Etudes et de Recherche sur le Matériau BoisEA 4370-USC INRAEUniversitéde LorraineNancy54506France laboratoire d’etudes et de Recherche sur le matériau Bois EA 4370-USC INRAEUniversitéde LorraineEpinal88000France

With the current trend of increasing efforts to develop non-isocyanate-based polyurethanes(NIPUs),this study aimed to check the feasibility of the development of a method using cyclic carbonate modified catechin and amine to synthesis non-isocyanate urethane with the objective to further extend these results to polyurethane *** methods used in this study consist of four steps:glycidilation of catechin,hydrolysis of epoxide,cyclic carbonate synthesis,and carbamate synthesis through condensation of *** resulting products were analyzed using FTIR(Fourier transform infrared)spectroscopy and NMR(nuclear magnetic resonance)*** results showed that carbamate could be successfully obtained through this four-steps synthesis,opening the possibility to further developments for the synthesis of polyurethanes starting from catechin and condensed tannins.

关键词： Catechin cyclic carbonate isocyanate-free glycidilation carbamate

Microwave Synthesis of Large Few-Layer Graphene Sheets in Aqueous Solution of Ammonia

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Nano Research 2010年第2期3卷 126-137页

作者： Izabela Janowska Kambiz Chizari Ovidiu Ersen Spyridon Zafeiratos Driss Soubane Victor Da Costa Virginie Speisser Christine Boeglin matthieu Houllé Dominique Bégin Dominique Plee Marc-Jacques Ledoux Cuong Pham-Huu laboratoire des matériaux Surfaces et Procédés pour la Catalyse(LMSPC)UMR7515 CNRS-Universitéde Strasbourg 25rue Becquerel67087 Strasbourg Cedex 08France Institut de Physique et Chimie des matériaux de Strasbourg(IPCMS) UMR7504 CNRS-Universitéde Strasbourg 23rue du Loess67037 Strasbourg Cedex 02France Arkema Groupement de Recherche de Lacq(GRL)BP 3464170 LACQFrance

Few-layer graphene (FLG) sheets with sizes exceeding several micrometers have been synthesized by exfoliation of expanded graphite in aqueous solution of ammonia under microwave irradiation, with an overall yield approaching 8 wt.%. Transmission electron microscopy (in bright-field and dark-field modes) together with electron diffraction patterns and atomic force microscopy confirmed that this graphene material consisted mostly of mono-, bi- or few-layer graphene (less than ten layers). The high degree of surface reduction was confirmed by X-ray photoelectron and infrared spectroscopies. In addition, the high stability of the FLG in the liquid medium facilitates the deposition of the graphene material onto several substrates via low-cost solution-phase processing techniques, opening the way to subsequent applications of the material.

关键词： Graphene transmission electron microscopy(TEM) expanded graphite exfoliation microwaves

A Simplified Numerical Study of the Kr/Cl_2 Plasma Chemistry in Dielectric Barrier Discharge

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Plasma Science and Technology 2013年第4期15卷 343-349页

作者： N.LARBI DAHO BACHIR A.BELASRI laboratoire de physique des plasmas mat'eriaux conducteurs et leurs applications LPPMCA Universit'e USTO'MBOran Algeria

In this paper, the generation of excimers and exciplexe radiation in mixtures of rare gas with halogen by homogeneous dielectric barrier discharge （DBD） is investigated. The typical characteristics of an excilamp based on KrCI＊ exciplexe molecules and the kinetic processes for the formation and the decay of this molecules in the Kr/Cl2 mixture are studied. The computer model developed is based on the Kr/Cl2 mixture chemistry, the equivalent electric circuit and the Boltzmann equations. The importance in the kinetic processes of some species such as the metastable state of Krypton （Kr＊（3P0,2）） and the negative ion of chloride （C1-） is considered. The results illustrate the time variations of charged species （ne, Kr＋, CI-, Cl＋, Cl＋, Kr＋）, excited atoms and molecules （Kr＊（3p0,2）, Kr＊（3P1）, Cl＊, Cl2）, the excimers （Kr, KrCl＊（B）, KrCI＊（C）, Kr2Cl＊） and the UV photon concentrations （in 222 nm, 235 nm, 258 nm and 325 nm range）. The effects of chlorine concentration and the total gas pressure in the Kr-Cl2 discharge on the electric parameters and radiation emissions are investigated.

关键词： rare gas kinetic homogenous discharge dielectric barrier discharge KrCl*excilamp