0000000000620364

AUTHOR

Gerhard Geipel

showing 3 related works from this author

Mixed complexes of alkaline earth uranyl cabonates: A laser-induced time-resolved fluorescence spectroscopic study

2008

The interaction of the alkaline earth ions Mg2+, Sr2+ and Ba2+ with the uranyl tricarbonate complex has been studied by time resolved laser-induced fluorescence spectroscopy. In contrast to the non-luminescent uranyl tricarbonate complex the formed products show slight luminescence properties. These have been used to determine the stoichiometry and complex stabilities of the formed compounds. As the alkaline earth elements are located in an outer shell of the complex the influence of the type of the alkaline earth element on the stability constant is not very drastic. Therefore all obtained data were averaged in order to derive an common stability constant for the described complexes. These…

LuminescenceLightAnalytical chemistryCarbonateschemistry.chemical_elementFluorescence spectroscopyAnalytical ChemistryPhosphatesuraniumchemistry.chemical_compoundAlkaline earth elementscarbonatecomplex formationluminescenceMagnesiumInstrumentationSpectroscopyIonsAlkaline earth metalModels StatisticalTemperatureBariumHydrogen-Ion ConcentrationUranylAtomic and Molecular Physics and OpticsCarbonSpectrometry FluorescencechemistryStability constants of complexesBariumStrontiumUraniumTime-resolved spectroscopyLuminescenceStoichiometry
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Spectroscopic characterization of alkaline earth uranyl carbonates

2005

A series of alkaline uranyl carbonates, M[UO{sub 2}(CO{sub 3}){sub 3}].nH{sub 2}O (M=Mg{sub 2}, Ca{sub 2}, Sr{sub 2}, Ba{sub 2}, Na{sub 2}Ca, and CaMg) was synthesized and characterized by inductively coupled plasma mass spectrometry (ICP-MS) and atomic absorption spectrometry (AAS) after nitric acid digestion, X-ray powder diffraction (XRD), and thermal analysis (TGA/DTA). The molecular structure of these compounds was characterized by extended X-ray absorption fine-structure (EXAFS) spectroscopy and X-ray photoelectron spectroscopy (XPS). Crystalline Ba{sub 2}[UO{sub 2}(CO{sub 3}){sub 3}].6H{sub 2}O was obtained for the first time. The EXAFS analysis showed that this compound consists of …

spectroscopysynthesisAbsorption spectroscopyTRLFSAnalytical chemistryElectron spectroscopyUranyl carbonateuraniumInorganic Chemistrycarbonatechemistry.chemical_compoundXPSMaterials ChemistrystructurePhysical and Theoretical ChemistrySpectroscopyX-ray spectroscopyExtended X-ray absorption fine structureChemistryCondensed Matter PhysicsUranylalkaline earthElectronic Optical and Magnetic MaterialsEXAFSX-ray crystallographyCeramics and CompositesJournal of Solid State Chemistry
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Uranium speciation in plants

2002

The chemical characterization of the radionuclide species is essential for a reliable assessment of the migration of radionuclides and heavy metals into the geological and biological environment on the load pathway soil - plant - animal - human. Only a few is known about the speciation of uranium in plants. Therefore we investigate the change of speciation during the transfer of uranium from initial solution into plant. Various plants (lupins, dandelion e.g.) were grown in an agricultural test field and in the laboratory on contaminated soils (up to concentration of 1g U/kg soil) and as hydroponics in the uranium containing solutions (uranium concentration: 10-5 M - 10-2 M, pH: 3 - 8). For …

inorganic chemicalsChemistryChemical speciationfungiUranium phosphateRadiochemistrytechnology industry and agriculturefood and beverageschemistry.chemical_elementUraniumcomplex mixturesUranyl carbonateFluorescence spectroscopychemistry.chemical_compoundEnvironmental chemistryGenetic algorithmSpectroscopy
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