0000000000002832

AUTHOR

Nissrine Zaiter

showing 3 related works from this author

Efficiency of dihydroxamic and trihydroxamic siderochelates to extract uranium and plutonium from contaminated soils

2021

International audience; Actinide-based mineral phases occurring in contaminated soils can be solubilized by organic chelators excreted by plants, such as citrate. Herein, the efficiency of citrate towards U and Pu extraction is compared to that of siderophores, whose primary function is the acquisition of iron(III) as an essential nutrient and growth factor for many soil microorganisms. To that end, we selected desferrioxamine B (DFB) as an emblematic bacterial trishydroxamic siderophore and a synthetic analog, abbreviated (LCy,Pr)H2, of the tetradentate rhodotorulic acid (RA) produced by yeasts. Firstly, the uranyl speciation with both ligands was assessed in the pH range 2–11 by potentiom…

Siderophore010504 meteorology & atmospheric scienceshydroxamic acidHealth Toxicology and Mutagenesis010501 environmental sciencesFerric Compounds01 natural sciencesActinidesSoilchemistry.chemical_compoundRadiation MonitoringEnvironmental Chemistry[CHIM]Chemical Sciencescitratesolid-liquid distributionWaste Management and DisposalEquilibrium constantChemical decomposition0105 earth and related environmental sciences[PHYS]Physics [physics]Hydroxamic acidExtraction (chemistry)General MedicineUranylPollutionPlutoniumRhodotorulic acidchemistryspeciation[SDE]Environmental SciencesUraniumSelectivityNuclear chemistry
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Dielectric relaxation phenomenon and conductivity in lead-free ceramics

2018

Abstract Relaxation phenomena and electric conductivity of (1-x) KNbO3-xK0.5Bi0.5TiO3 system where x = 0, 0.025, 0.05, 0.075, 0.1, 0.2, 0.3 have been studied at high temperature. A relaxation behavior was observed in temperature range 400 K ≤ T ≤ 550 K for orthorhombic solid solutions at room temperature. The activation energy (Ea) of this phenomenon was range from 0.68 eV for x = 0–0.489 eV for x = 0.075 with τ0 = 10−13 s. The relaxation was attributed to hopping of oxygen vacancies for solid solutions x ≤ 0.075. Substitution by K0.5Bi0.5TiO3 does not affect the electrical conductivity of KNbO3 too much, while the mobility of species such as oxygen vacancies and oxygen ions allow the incre…

Materials scienceCondensed matter physicschemistry.chemical_element02 engineering and technologyActivation energyDielectricConductivityAtmospheric temperature range010402 general chemistry021001 nanoscience & nanotechnologyCondensed Matter Physics01 natural sciencesOxygen0104 chemical sciencesElectronic Optical and Magnetic MaterialschemistryElectrical resistivity and conductivityRelaxation (physics)Electrical and Electronic Engineering0210 nano-technologySolid solutionPhysica B: Condensed Matter
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Thermodynamic studies of iron(III) complex of some new dihydroxamic acids model of rhodotorulic acid

2018

Abstract The objective of this research is to elucidate the coordination chemistry and the structure of complexes formed with siderochelates organic ligands and the physico-chemical studies of iron(III) complexation. Three dihydroxamic acids synthesized ((LCyEt)2−, (LCyPr)2− and (LO)2−) mimicking a fungal siderophore, rhodotorulic acid. They were evaluated with iron(III) chelation by potentiometric and spectrophotometric titrations in 0.1 M KNO3. These measurements revealed the formation of dileptic and trileptic complexes in excess ligand conditions. The chemical model includes five species of [Fem(L)lHh](3m−2l+h)+ with general formula: [Fe(L)]+, [Fe(L)(OH)], [Fe(L)(OH)2]−, [Fe(L)2H] and […

chemistry.chemical_classificationAbsorption spectroscopy010405 organic chemistryChemistryLigandElectrospray ionizationPotentiometric titration010402 general chemistry01 natural sciencesMedicinal chemistry0104 chemical sciencesCoordination complexInorganic ChemistryRhodotorulic acidchemistry.chemical_compoundMaterials ChemistryTitrationChelationPhysical and Theoretical ChemistryInorganica Chimica Acta
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