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Journal of Environmental Sciences 2011年第5期23卷 860-867页

作者： Bochra Bejaoui Kefi Latifa Latrous El Atrache Hafedh Kochkar Abdelhamid Ghorbel laboratoire des matériaux Utiles Institut National de Recherche et d'Analyse Physico-chimiqueple technologique Sidi-Thabet 2020 Tunis Tunisia laboratoire de chimie analytique et Electrochimie Département de Chimie Facultédes Sciences de TunisCampus Universitaire2092 EL Manar TunisTunisia laboratoire de chimie des matériaux et Catalyse Facultédes Sciences de TunisCampus Universitaire2092 EL Manar Tunis Tunisia

An analytical method based on TiO2 nanotubes solid-phase extraction （SPE） combined with gas chromatography （GC） was established for the analysis of seven polycyclic aromatic hydrocarbons （PAHs）： acenaphtylene, acenaphthene, anthracene, fluorene, phenanthrene, fluoranthene and pyrene. Factors affecting the extraction efficiency including the eluent type and its volume, adsorbent amount, sample volume, sample pH and sample flow rate were optimized. The characteristic data of analytical performance were determined to investigate the sensitivity and precision of the method. Under the optimized extraction conditions, the method showed good linearity in the range of 0.01-0.8 μg/mL, repeatability of the extraction （RSd were between 6.7% and 13.5%, n = 5） and satisfactory detection limits （0.017-0.059 μg/mL）. The developed method was successfully applied to the analysis of surface water （tap, river and dam） samples. The recoveries of PAHs spiked in environmental water samples ranged from 90% to 100%. All the results indicated the potential application of titanate nanotubes as solid-phase extraction adsorbents to pre-treat water samples.

关键词： Ti02 nanotubes hydrothermal treatment solid phase extraction gas chromatography polycyclic aromatic hydrocarbons

Synthesis, Structural Study and Phase Transitions Characterization by Thermal Analysis and Vibrational Spectroscopy of an Ammonium Rubidium Arsenate Tellurate

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Chemical Research in Chinese Universities 2016年第6期32卷 902-911页

作者： GHORBEL Khouloud LITAIEm Hajer KTARI Lilia GARCIA-GRANdA Santiago dAmmAK mohamed laboratoire de chimie Inorganique(LCI) Universitd de Sfax Facultd des Sciences de Sfax BP 1171 Sfax 3000 Tunisia laboratoire de chimie Physique et analytique Faeulte de Chimie Universitte d 'Oviedo Oviedo 33006 Espagne

The Rb2.42（NH4）0.58（HAsO4）（H2AsO4）. Te（OH）6 crystals（denoted by RbNAsTe） crystallize in the monoc-linic system, space group P21/n with the following parameters： a=1.3059（5） nm, b=0.6755（3） nm, c=1.6675（6） rim,β=94.126（4）°, Z=4 and V=1.46733（10） nm^3. Thermal analyses（dSC, dTA and TG） confirm the presence of the phasetransition and the temperatttre of the decomposition. The vibrational spectroscopy study at room temperature showthe presence and the independence of anionic groups, cationic groups, and give more importance to the hydrogenbonds. Raman spectra were recorded in the temperature range of 298--503 K. The temperature dependence of theRaman line shift, intensity reduction and the half width detects the phase transitions and confirms their nature. So, thephase transition at 453 K corresponds to the superprotonic-ionic conduction phase transition, and those at 483 and491 K correspond to the decomposition of our material.

关键词： RbNAsTe X-Ray diffraction differential scanning calorimetry Phase transition Raman spectrometry

RING OPENING POLYmERIZATION OF TetRAHYdROFURAN CATALYSEd BY mAGHNITE-H^+

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Chinese Journal of Polymer Science 2012年第1期30卷 56-62页

作者： Khadidja Benkenfoud Amine Harrane mohammed Belbachir laboratoire de chimie des Polymeres departement de chimie Faculte des SciencesUniversite d'Oran Es-SeniaBP No 1524 El M'Naouar31000 OranAlgeria

The cationic ring-opening polymerization of tetrahydrofiiran using maghnite-H~＋ is ***-H~＋,is a non-toxic solid catalyst issued from proton exchanged montmorillonite ***,also called ＂poly（butandiol） ether＂,with acetate and hydroxyl end groups was successfully *** of reaction temperature, weight ratio of initiator/monomer and reaction time on the conversion of monomer and on the molecular weight are investigated.A cationic mechanism of the reaction was *** chemistry can be considered as a suitable route for preparing poly（THF） as a soft segment for thermoplastic elastomers.

关键词： montmorillonite maghnite Ring opening polymerization THF

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

Synthesis and Electrical Properties of Well-Ordered Layered α-moO_3 Nanosheets

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Nano-micro Letters 2011年第4期3卷 242-248页

作者： R.Naouel H.dhaouadi F.Touati N.Gharbi laboratoire de chimie de la matière Condensée Université de Tunis.Institut Préparatoire aux Etudes d’Ingénieur de Tunis "laboratoire des matériaux Utiles" Institut National de Recherche et d’analyse Physico-chimique

α-moO_3 ordered nanosheets have been synthesized under hydrothermal conditions using commercial moO_3 and hydroquinone as structuring agent. X-ray diffraction(XRd), scanning electron microscope(SEm) and transmission electron microscopy(TEm) were used to analyse the obtained material. The conductivity mechanism of the molybdenum ordered nanosheets has been investigated using combined complex impedance and modulus *** temperature dependence of the conductivity, which was between 473 and 573 K, is very close to the Arrhenius' law, with an activation energy of 0.76 eV. However, the conductivity of the material increases with temperature. It shows a typical negative temperature coefficient resistance(NTCR) similar to that of a semiconductor. The dielectric properties of the moO_3 compound have been studied in the temperature range of 473-573 K as well as the frequency range of 10 Hz to 13 mHz. The ac-conductivity for high frequency σac(ω)obeys the universal power law.

关键词： Electron microscopy Hydrothermal synthesis X-ray diffraction Electrical properties

Structure, Thermal Behavior and Characterization of a New Hybrid Iron Fluoride FeF4（2,2′-bipyridine）（H2O）2

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Chemical Research in Chinese Universities 2015年第1期31卷 16-20页

作者： mouna SmIdA Hager LITAIEm mohamed dAmmAK Santiago GARCIA-GRANdA laboratoire de chimie Inorganique Faculte des Sciences de Sfax Universite de Sfax 3000Sfax Tunisie departement de chimie Physique Analytique Faculte de Chimie Universite d'Oviedo-CINN 33006 Oviedo Spain

New crystal of FeF4（2,2′-bipyridine）（H2O）2 was prepared by hydrothermal synthesis. Crystalline structure determination is performed from single crystal X-ray diffraction data. The unit cell is monoclinic space group P21/n, with cell parameters a=0.9046（5） nm, b=0.7502（5） nm, c=1.9539（5） nm,β=93.307（5）°, V=1.3238（12） nm^3 and Z=4. The structure of FeF4（2,2＇-bipyridine）（H2O）2 is built up from FeF4N2 octahedra coordinated by two nitrogen atoms of the 2,2＇-bipyridine molecules, and four fluorine atoms as well as uncoordinated H2O molecules. Thermal analysis of the title compound showed that the decomposition introduced four steps. IR spectra confirmed the presence of 2,2＇-bipyridine molecules. The optical absorption was measured at the corresponding 2max using UV-Vis diffuse reflectance spectrum.

关键词： Hydrothermal synthesis Hybrid Iron fluoride

Anti-inflammatory and analgesic activities with gastroprotective effect of semi-purified fractions and isolation of pure compounds from mediterranean gorgonian Eunicella singularis

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Asian Pacific Journal of Tropical medicine 2015年第8期8卷 598-603页

作者： monia deghrigue Carmen Festa Lotfi Ghribi maria Valeria d’Auria Simona de marino Hichem Ben Jannet Abderrahman Bouraoui laboratoire de développement chimique galénique et pharmacologique des médicaments (LR12ES09).Equipe de Pharmacologie marineFaculté de pharmacie de MonastirUniversité de Monastir department of Pharmacy University of Naples "Federico II" laboratoire de chimie hétérocyclique produits naturels et réactivité. Equipe de chimie médicinale et produits naturels (LR11ES39)Faculté des sciences de MonastirUniversité de Monastir laboratoire de chimie hétérocyclique produits naturels et réactivité.Equipe de chimie médicinale et produits naturels (LR11ES39)Faculté des sciences de MonastirUniversité de Monastir

Objective: To explore anti-inflammatory activities of organic extract and its semi-purified fractions(ethanol, acetone, methanol/dichloromethane) from the mediterranean gorgonian Eunicella singularis. methods: The anti-inflammatory and analgesic activities were evaluated, using the carrageenan-induced rat paw edema model and the acetic acid writhing test in mice. The gastroprotective activity was determined using HCl/et OH induced gastric ulcers in rats. The purification and structure elucidation of compound(s) from the more effective fraction were determined by chromatographic and spectroscopic methods and in comparison with data reported in the literature. Results: The fraction F-et OH showed an important antiinflammatory activity associated with significant analgesic and gastroprotective properties. The purification and structure elucidation of compound(s) from this fraction lead to the identification of one diterpenoid and four sterols. Conclusions: These results suggested that components from the active fraction can be used to treat various anti-inflammatory diseases.

关键词： Eunicella singularis Anti-inflammatory activity Analgesic activity Gastroprotective effect diterpenoid Sterols

SYNTHESIS OF SOLUBLE POLY(3,4-dIHYdROXY-o-TOLYLENE):REdOX POLYmER

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Chinese Journal of Polymer Science 2006年第1期24卷 41-46页

作者： Sad moulay Fatima m'zyène laboratoire de chimie-Physique moléculaire et macromoléculaire Faculté des Sciences de l'Ingénieur département de chimie Industrielle Université de BlidaRoute de SoumèaB.P.270Blida 09000Algeria. laboratoire de chimie-Physique moléculaire et macromoléculaire Faculté des Sciences de l'Ingénieur département de chimie Industrielle Université de BlidaRoute de SoumaB.P.270Blida 09000Algeria.

Conventional chloromethylation, paraformaldehyde/hydrogen chloride in acetic acid medium, was applied to 1,2- dimethoxybenzene. Chloroform-soluble poly（3,4-dimethoxy-o-tolylene） was obtained with an intrinsic viscosity of 0.034 dL g^-1. The polymer was evaluated as a condensation redox polymer precursor formed by a Friedel-Crafts reaction. Cleavage of the methoxy groups present in this polymer resulted in poly（3,4-dihydroxy-o-tolylene） which manifested a great air-oxidation resistance. The redox property of the latter polymer was found to be 1017 mV by potentiometric titration with 0.05 N ceric ammonium nitrate at 25℃. This midpotential was compared to that of catechol, a monomeric analogue, under the same titration conditions.

关键词： Poly(3,4-dimethoxy-o-tolylene) Poly(3,4-dihydroxy-o-tolylene) Redox polymer.

Adsorption properties of Rosmarinus officinalis oil as green corrosion inhibitors on C38 steel in 0.5 m H_2SO_4

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Acta metallurgica Sinica(English Letters) 2010年第1期23卷 13-20页

作者： E.El Ouariachi J.Paolini m.Bouklah A.Elidrissi A.Bouyanzer B.Hammouti J-m.desjobert J.Costa laboratoire de chimie Appliqu'ee et Environnement Facult'e des SciencesUniversit'e Mohamed PremierBP71760000 OujdaMorocco UmR CNRS 6134 Laboratoire de Chimie des Produits NaturelsUniversit'e de CorseFrance

Rosmarinus officinalis essential oil obtained by hydrodistillation was tested as corrosion inhibitor of steel in 0.5 m H2SO4 using weight loss measurements, and electrochemical .polarisation methods. Results obtained indicate that the corrosion rate is reduced and R. officinalis oil adsorbs on the metal surface and then inhibits corrosion process. Its inhibition efficiency increases with oil increasing content to reach 61% at 1 g/L. Polarisation curves indicate that RO acts as a cathodic inhibitor. The inhibition efficiency of naturally oil remains slightly constant with the rise of temperature. Chemical analysis of R. officinalis essential oil was carried out using capillary GC and GC/mS. The oil composition was characterized by high amount of oxygenated monoterpene （77%） with 1,8-cineol （52.1%） as main component. discussion of adsorption was investigated on the the isotherm adsorption of essential oil on basis of essential oil composition. Finally the steel has been also reported.

关键词： Rosmarinus officinalis oil Adsorption Corrosion Inhibition Steel 1,8-cineol

Optimised NSAIds-loaded Biocompatible Nanoparticles

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Nano-micro Letters 2010年第4期2卷 247-255页

作者： V.Gaelle ROULLIN maaite CALLEWAERT michael mOLINARI Franck deLAVOIE Aurelie SECONde marie-Christine ANdRY Institut de chimie mole culaire de Reims CNRS UMR 6229UFR Pharmacie Reims laboratoire de microscopies et d’etudes des Nanostructures UFR des SciencesUniversitéde Reims Champagne-Ardenne laboratoire de microscopie Electronique analytique INSERM UMRS 92621 rue Clement Ader51685 Reims Cedex 2France

In this formulation study,biocompatible non steroidal anti-inflammatory(NSAIds)-loaded nanoparticles were designed as models to be further integrated in a prosthesis surface functionalization.A modified spontaneous emulsion-solvent diffusion methodology was used to produce drug-loaded PLGA nanoparticles without any purification or solvent evaporation *** parameters,such as lactide/glycolide ratio,polymer concentration,solvent/non solvent ratio and non solvent phase,as well as the non ionic tensioactive P188 co-precipitation composition were systematically *** optimized formulation(mean size:145 nm,surface charge:-13 m V) was employed to encapsulate various amounts of NSAIds in a simple and scalable *** drug release was characterized in vitro by a complete release for 48 *** results encourage upcoming preliminary steps for in vivo experiments of prosthesis surface functionalization.

关键词： drug delivery systems(ddS) Biocompatible Emulsion-solvent diffusion method PLGA Glycofurol Non steroidal anti-inflammatory drugs(NSAIds)