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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

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

Electronic and Optical Properties of TiS2 Determined from Generalized Gradient Approximation Study

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Chinese Physics Letters 2015年第9期32卷 96-99页

作者： Hamza El-Kouch Larbi El Farh Jamal Sayah Allal Challioui laboratoire de mecanique & energetique Departement de Physique Faculte des Sciences Universite Mohmnmed Premier Oujda Maroc laboratoire de chimie organique macromol~culaire et produits naturels Equipe: Photochimie et Chimie Macromoleculaire Faculte des Sciences Universite Mohammed Premier Oujda. Maroc

The electronic and optical properties of TiS2 are studied of density functional theory. A linearized and augmented by using an ab-initio calculation within the frame plane wave basis set with the generalized gradient approximation as proposed by Perdew et al. is used for the energy exchange-correlation determination. The results show a metallic character of TiS2, and the plots of total and partial densities of states of TiS2 show the metallic character of the bonds and a strong hybridization between the states d of Ti and p of S below the Fermi energy. The optical properties of the material such as real and imaginary parts of dielectric constant （ε（w） = ε1（w）＋ iε2（w））, refractive index n（w）, optical reflectivity R（w）, for E / /x and E / /z are performed for the energy range of 0-.14 eV.

关键词： Ti ab Electronic and Optical Properties of TiS2 Determined from Generalized Gradient Approximation Study

Effect of Water Quality on Heavy Metal Redistribution and Mobility in Polluted Agricultural Soils in a Semi-Arid Region

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Pedosphere 2019年第6期29卷 730-739页

作者： Rim AZOUZI Abdelkrim CHAREF Lamia AYED Samia KHADHAR laboratoire Géoressources Centre des Recherches et Technologies des EauxSoliman 8020(Tunisia) laboratoire d’Analyse Traitement et Valorisation des Polluants de l’Environnement et des ProduitsFacultéde PharmacieRue AvicenneMonastir 5000(Tunisia)

Mornag Plain is a coastal area of the Mediterranean basin, which has undergone an agricultural industrial boom. The aim of this study was to investigate the different water qualities used for irrigation on heavy metal mobility in these polluted agricultural soils. The geo-accumulation indices for heavy metals (Ni, Cr, Pb, Cd, Cu, and Zn) revealed that industrial activities and used treated wastewater (TWW) contributed to soil pollution, and water irrigation always decreased this contamination. After long-term use of different water types, high perturbation of heavy metal redistribution has occurred. Groundwater use altered all heavy metal redistributions in the irrigated soil among various soil-solid and soil-solution fractions, as compared to the unirrigated soil. Slight acid water use transferred some metals from different solid phase components into water-soluble and exchangeable fractions. However, TWW use transformed some Ni, Cr, Cd, Cu, and Zn from water-soluble and exchangeable fractions to less labile fractions, particularly into organically bound fractions. Reuse of conventional water within the same soil decreased the whole soil redistribution index values, indicating tendency to return to the pattern of distribution of groundwater-irrigated soil.

关键词： Exchangeable fraction Geo-accumulation index Labile fraction Mobility factor Organically bound fraction Redistribution index Treated wastewater Water-soluble fraction

Phosphorus mobility in dam reservoir affected by redox oscillations:An experimental study

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Journal of Environmental Sciences 2019年第3期31卷 250-263页

作者： Anne Rapin Malgorzata Grybos Marion Rabiet Brice Mourier Véronique Deluchat Université de Limoges PEIRENE EA 7500 Faculté des Sciences et Techniques Université de Lyon UMR5023 laboratoire d'Ecologie des Hydrosystèmes naturels et Anthropisés Université Lyon 1ENTPE CNRS

The internal sedimentary phosphorus(P) load of aquatic systems is able to support eutrophication, especially in dam–reservoir systems where sedimentary P stock is high and where temporary anaerobic conditions occur. The aim of this study therefore is to examine the response of sedimentary P exposed to redox oscillations. Surface sediments collected in the Champsanglard dam–reservoir(on the Creuse River, France) were subjected to two aerobic phases(10 and 12 days) alternated with two anaerobic periods(21 and 27 days)through batch incubations. The studied sediment contained 77 ± 3 μmol/g DW of P, mainly associated with the ascorbate fraction(amorphous Fe/Mn oxyhydroxides). The used sediment was rich in organic matter(OM)(21% ± 1%) with primarily allochthone *** results showed that redox oscillations enhance dissolved inorganic phosphorus release at sediment/water interface. During the first anaerobic stage, the P release was mainly controlled by the dissolution/precipitation of iron minerals. The more pronounced increase of P release during the second anaerobic stage(44%) was due to various mechanisms related to the change in quality of dissolved organic matter(DOM), namely a higher SUVA254 and humification indices. The release of more refractory DOM(rDOM) served to lower the microbial metabolism activity, possibly favored iron oxyhydroxide aggregation and thus limiting iron reduction. In addition, rDOM is able to compete for mineral P sorption sites,leading to a greater P release. In reservoir with predominant allochthone OM input, the release of more aromatic DOM therefore plays an important role in P mobility.

关键词： Phosphorus Sediment Redox Iron Organic matter

Selective and taxon-dependent effects of semi-feral cattle grazing on tree regeneration in an old-growth Mediterranean mountain forest

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Forest Ecosystems 2020年第1期7卷 128-140页

作者： Xavier Fortuny Christopher Carcaillet Sandrine Chauchard Ecole Pratique des Hautes Etudes(EPHE) PSL University75014 ParisFrance laboratoire d’ cologie des Hydrosystèmes naturels et Anthropisés(UMR5023 CNRS UniversitéLyon 1ENTPE)69622 VilleurbanneFrance Universitéde Lorraine AgroParisTechINRAEUMR Silva54000 NancyFrance

Background:In Mediterranean mountain socio-ecosystems,both grazing by livestock and the dry season may influence tree ***,the relative contributions of these drivers are poorly known,even though present and future canopy composition might result from past and present variations in climate and herbivore *** study aims to test how semi-feral cattle presence and season affect tree ***:The study was conducted using permanent plots inside and outside a cattle exclosure in an old-growth Mediterranean *** and seedlings were counted five times per year(winter,early spring,middle spring,summer,fall)and monitored over 7 ***:Semi-feral cattle exclusion increased Acer,Fagus,Ilex,Pinus,Prunus and Quercus sapling densities and increased Acer,Fraxinus,Ilex,Quercus and Sorbus seedling ***,the dry season did not exert any noticeable effects on the sapling or seedling densities of any of the studied ***:Semi-feral cattle presence may limit tree regeneration through taxon-dependent effects,which suggests that the current decrease in grazing livestock across the Mediterranean basin will modify recruitment processes and,likely,future forest ***:Semi-feral cattle presence acts as a selective driver of tree community composition.

关键词： Cattle Climate Experiment Herbivory Forest pastoralism

Synthesis of(±)-phthalascidin 622

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Science China Chemistry 2010年第9期53卷 1888-1898页

作者： CHRISTIAN R.Razafindrabe SYLVAIN Aubry BENJAMIN Bourdon MARTA Andriantsiferana STEPHANE Pellet-Rostaing MARC Lemaire laboratoire de Chimie des produits naturels et Biotechnologie(LPNB) Université d'Antananarivo17 Cité Mahatazana-Ampandrianomby101 Antananarivo ICBMS Institut de Chimie et Biochimie Moléculaires et SupramoléculairesCNRSUMR5246Laboratoire de Catalyse et Synthèse Organique ICSM institut de Chimie Séparative de MarcouleCNRS/CEA/UM2/ENSCMUMR 5257Laboratoire de Tri Ionique par des Systèmes Moléculaires auto-assemblés

A synthesis of functionalized phenolic α-amino-alcohols(±)-8 and(±)-16 as synthetic precursors of the catechol tetrahydroisoquinoline structure of phthalascidin 650 was disclosed.(±)-8 was prepared in 5 steps from the commercially available *** from 3-methyl catechol 5,8 steps gave rise to the synthesis of phenolic α-amino-alcohol(±)-16 in 27% overall *** synthetic strategy involved the elaboration of fully functionalized aromatic aldehyde 13 and its transformation into a phenolic α-amino-alcohol(±)-16,through a Knoevenagel condensation,simultaneous reduction of nitroketene and ester functions,and hydrogenolysis of the benzyl protecting *** pentacycle(±)-4 was obtained after 4 additional *** Pictet-Spengler cyclisation between the phenolic α-amino-alcohol(±)-16 and the N-protected α-amino-aldehyde 4 allowed to obtain(1,3')-bis-tetrahydroisoquinoline 17 with N-methylated and N-Fmoc *** last step was a Swern oxidation allowing the expected intramolecular condensation.

关键词： phthalascidin ecteinascidin (1 3’)-bis-tetrahydroisoquinoline Pictet-Spengler Bishler-Napieralsky

Synthesis and Photophysical Properties of Novel Rod-shaped and Star Shaped Fluorescent Phosphane Derivatives

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复旦学报（自然科学版） 2007年第5期46卷 590-,592页

作者： Isabelle Leray Minh-Huong Ha-Thi Véronique Michelet laboratoire PPSM ENS-Cachan61 Avenue du Président Wilson94235 CachanFrance laboratoire de Synthèse Sélective Organique et produits naturels ENSCPUMR 757311 rue Pierre et Marie Curie 75231 Paris Cedex 05France

1 Results Over the past few years significant research has been directed toward the development of organic materials for potential application in molecular photonic devices[1] and the development of sensors[2].Interest in these materials is primarily due to the infinite numbers of possible molecular structures with the desired properties,by virtue of the tremendous capabilities of organic *** the development of a new fluorescent molecular sensor consisting of a recognition moiety linked to a f...

关键词： synthesis photophysical procperties fluorescent phosphane derivatives

A new friedelane triterpenoid and saponin with moderate antimicrobial activity from the stems of Drypetes laciniata

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Chinese Chemical Letters 2011年第2期22卷 171-174页

作者： Simone Veronique Fannang Victor Kuete Celine Mbazoa Djama Marlise Diane J.Dongfack Jean Duplex Wansi Francois Tillequin Elisabeth Seguin Elizabeth Chosson Jean Wandji laboratoire de Synthese et de produits naturels Departement de Chimie Organique de l'Universite de Yaounde-1Faculte des SciencesP.O.Box 812 YaoundeCameroon Department of Biochemistry University of DschangFaculty of ScienceP.O.Box 67 DschangCameroon laboratoire de Pharmacognosie de l'Universite Paris descartes UMR/CNRS No.8638Faculte des Sciences Biologiques et Pharmaceutiques4-Avenue de l'Observatoire75006 ParisFrance Department of Chemistry University of DoualaFaculty of ScienceP.O.Box 24157 DoualaCameroon laboratoire de Pharmacognosie UFR de Medecine Pharmacie Rouen22-Bld Gambetta76183 Rouen Cedex 1France

A new friedelane-type triterpene named 3β-hydroxyfriedelane-7,12,22-trione,as well as nine known compounds were isolated from the whole stems of Drypetes laciniata Hutch.（Euphorbiaceae）.Their structures were established on the basis of spectroscopic *** new triterpene derivative and a known saponin were tested for antimicrobial and antifungal activities and they appeared to be moderate active.

关键词： Drypetes laciniata Euphorbiaceae Stem Friedelane-type triterpenoid Antimicrobial activity