0000000000204955

AUTHOR

Aleksej Zarkov

0000-0002-3574-2296

showing 9 related works from this author

Effect of Mn doping on the low-temperature synthesis of tricalcium phosphate (TCP) polymorphs

2019

Abstract Effect of Mn doping on the low-temperature synthesis of tricalcium phosphate (TCP) polymorphs was demonstrated in α- and β-TCP polymorphs prepared by wet precipitation method under identical conditions and annealed at 700 °C. Calcium phosphates with Mn doping level in the range from 1 to 5 mol% were studied and the formation of desired polymorph was controlled by varying Mn content in as-prepared precipitates. It was found that increasing Mn content resulted in the formation of β-TCP, while α-TCP was obtained with low Mn doping level, whereas a mixture of two polymorphs was obtained for intermediate Mn concentrations. Moreover, doping with Mn ions allowed the synthesis of β-TCP at …

010302 applied physicsMaterials sciencePrecipitation (chemistry)Scanning electron microscopeDopingInfrared spectroscopy02 engineering and technology021001 nanoscience & nanotechnology01 natural sciencesIonlaw.inventionlaw0103 physical sciencesMaterials ChemistryCeramics and CompositesFourier transform infrared spectroscopyInductively coupled plasma0210 nano-technologyElectron paramagnetic resonanceNuclear chemistryJournal of the European Ceramic Society
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Heterogeneous fenton oxidation using magnesium ferrite nanoparticles for ibuprofen removal from wastewater: optimization and kinetics studies

2020

In this study, the catalytic properties of Fenton-like catalyst based on magnesium ferrite nanoparticles for IBP degradation were examined. Structural and morphological studies showed the low crystallinity and mesoporous structure for the catalyst obtained via a glycine-nitrate method. The influences of catalyst dosage, oxidant concentration, and solution pH on the pollutant degradation were investigated. The pseudo-first-order model describes kinetic data, and under optimal condition (catalyst dose of 0.5 g L-1, H2O2 concentration of 20.0 mM, and pH of 8.0), apparent rate constant reached 0.091 min-1. It was shown that Fenton reaction was mainly induced by iron atoms on the catalyst surfac…

inorganic chemicalshapetusMaterials scienceArticle SubjectKineticsNanoparticlejätevesi02 engineering and technology010501 environmental sciences01 natural sciencesCatalysisCrystallinitykatalyytitReaction rate constantT1-995General Materials ScienceTechnology (General)jäteveden käsittely0105 earth and related environmental sciencesvedenpuhdistusmagnesium ferrite ; ibuprofen removal ; fenton oxidationlääkeaineet021001 nanoscience & nanotechnologyibuprofeeniWastewaterChemical engineeringnanohiukkasetLeaching (metallurgy)0210 nano-technologyMesoporous material
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Impact of gadolinium on the structure and magnetic properties of nanocrystalline powders of iron oxides produced by the extraction-pyrolytic method

2020

The work has been done in frame of the TransFerr project. It has received funding from the European Union’s Horizon 2020 research and innovation program under the Marie Sklodowska-Curie grant agreement No. 778070. This research was also supported by Latvian Research Council project lzp-2018/1-0214. A.I.P. appreciates support from the Estonian Research Council grant (PUT PRG619).

Gadolinium impactMaterials scienceiron oxidesValeric acidGadoliniumIron oxidechemistry.chemical_element02 engineering and technologyThermal treatmentCoercivitymagnetization010402 general chemistryValerateExtraction-pyrolitic methodIron oxidesMagnetizationlcsh:Technology7. Clean energy01 natural sciencesArticlechemistry.chemical_compoundnanostructures:NATURAL SCIENCES:Physics [Research Subject Categories]extraction–pyrolitic methodGeneral Materials Sciencecoercivitylcsh:Microscopylcsh:QC120-168.85chemistry.chemical_classificationlcsh:QH201-278.5lcsh:TExtraction (chemistry)gadolinium impact021001 nanoscience & nanotechnologyNanocrystalline materialNanostructures0104 chemical sciencesiron oxides ; nanostructures ; gadolinium impact ; extraction–pyrolitic method ; magnetization ; coercivitychemistrylcsh:TA1-2040Magnetic nanoparticleslcsh:Descriptive and experimental mechanicslcsh:Electrical engineering. Electronics. Nuclear engineeringlcsh:Engineering (General). Civil engineering (General)0210 nano-technologylcsh:TK1-9971Nuclear chemistry
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Morphological and optical property study of Li doped ZnO produced by microwave-assisted solvothermal synthesis

2021

Abstract ZnO materials have been at the centre of many studies for decades. Doping of ZnO by lithium atoms is a prospective approach for compensation of n-type conductivity in the unintentionally doped ZnO aimed at obtaining p-type semiconductor. In this study, we have synthesized ZnO rod-like powders doped with lithium ions (0–0.65 atom%) by the new microwave-assisted solvothermal method in order to obtain greater photoluminescence intensity of ZnO emissions in the UV region. The obtained powders contain nanoparticles from 20 nm up to 250 nm depending on Li content. X-ray diffractometry and Raman spectroscopy were employed to characterise the structure of ZnO powders, scanning electron mic…

PhotoluminescenceMaterials scienceScanning electron microscopeMechanical EngineeringSolvothermal synthesisDopingZnO ; microwave-assisted ; solvothermal ; synthesis ; doping ; Li ; nanoparticlesAnalytical chemistrychemistry.chemical_elementNanoparticleCarrier lifetimeCondensed Matter Physicssymbols.namesakechemistryMechanics of MaterialssymbolsGeneral Materials ScienceLithiumRaman spectroscopy
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Synthesis, structural and luminescent properties of Mn-doped calcium pyrophosphate (Ca2P2O7) polymorphs

2022

The study was partially funded by the Swedish Research Council FORMAS project “Utilization of solid inorganic waste from the aquaculture industry as wood reinforcement material for flame retardancy” (grant no. 2018-01198). Vilnius University is highly acknowledged for financial support from the Science Promotion Foundation (MSF-JM-5/2021). This project has also received funding from European Social Fund (project No 09.3.3-LMT-K-712-19-0069) under grant agreement with the Research Council of Lithuania (LMTLT). The authors acknowledge the Center of Spectroscopic Characterization of Materials and Electronic/Molecular Processes ("SPECTROVERSUM" www.spectroversum.ff.vu.lt ) at the Lithuanian Nat…

calcium pyrophosphate ; polymorphs ; Mn doping ; photoluminescence.Multidisciplinary:NATURAL SCIENCES::Physics [Research Subject Categories]Scientific Reports
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Investigation of lanthanum substitution effects in yttrium aluminium garnet: importance of solid state NMR and EPR methods

2020

Copyright © 2020, Springer Science Business Media, LLC, part of Springer Nature

Materials scienceGeneralLiterature_INTRODUCTORYANDSURVEYchemistry.chemical_elementComputingMilieux_LEGALASPECTSOFCOMPUTING02 engineering and technologyCrystal structure010402 general chemistry01 natural sciencesGeneralLiterature_MISCELLANEOUSlaw.inventionBiomaterialschemistry.chemical_compoundLanthanumlawImpurityYttrium aluminium garnet:NATURAL SCIENCES:Physics [Research Subject Categories]Materials ChemistryLanthanumElectron paramagnetic resonanceHardware_MEMORYSTRUCTURESGeneral ChemistryYttrium021001 nanoscience & nanotechnologyCondensed Matter PhysicsSubstitution effectNMR0104 chemical sciencesElectronic Optical and Magnetic MaterialschemistrySolid-state nuclear magnetic resonanceComputingMethodologies_DOCUMENTANDTEXTPROCESSINGCeramics and CompositesPhysical chemistryEPR0210 nano-technologyLuminescenceJournal of Sol-Gel Science and Technology
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Synthesis and luminescent properties of Mn-doped alpha-tricalcium phosphate

2021

This project has received funding from European Social Fund (project No 09.3.3-LMT-K-712-19-0069) under grant agreement with the Research Council of Lithuania (LMTLT). Institute of Solid State Physics, University of Latvia as the Center of Excellence has received funding from the European Union’s Horizon 2020 Framework Programme H2020-WIDESPREAD-01-2016-2017-TeamingPhase2 under grant agreement No. 739508, project CAMART². The World Federation of Scientists is highly acknowledged for the National Scholarship to AZ. © 2021. This work is licensed under a CC BY-NC-ND 4.0 license.

Tricalcium phosphateMaterials scienceCenter of excellenceLibrary science02 engineering and technologyEuropean Social Fund01 natural sciences7. Clean energyMn doping0103 physical sciences:NATURAL SCIENCES:Physics [Research Subject Categories]Materials Chemistrymedia_common.cataloged_instanceMn dopedEuropean unionPhotoluminescenceLicensemedia_common010302 applied physicsProcess Chemistry and Technology021001 nanoscience & nanotechnologySurfaces Coatings and FilmsElectronic Optical and Magnetic MaterialsAlpha-tricalcium phosphateScholarshipα-TCPResearch councilCeramics and Composites0210 nano-technologyCeramics International
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Fe and Zn co-substituted beta-tricalcium phosphate (β-TCP): Synthesis, structural, magnetic, mechanical and biological properties

2020

This work was supported by the European Social Fund under the No. 09.3.3- LMT-K-712 “Development of Competences of Scientists, other Researchers and Students through Practical Research Activities” measure. AK would like to express sincere gratitude for Fellowship administrated by The Japan Society for the Promotion of Science (JSPS). Fellow’s ID No.: L12546. Authors are grateful to R. Vargalis (Vilnius University) for taking SEM images. © 2020. This work is licensed under a CC BY-NC-ND license.

inorganic chemicalsCalcium PhosphatesMaterials scienceEmbryo NonmammalianCytotoxicityIronStructural analysisBioengineering02 engineering and technology010402 general chemistrySpectrum Analysis Raman01 natural scienceslaw.inventionIonBiomaterialsParamagnetismMagnetizationsymbols.namesakeMagneticsSpectroscopy MossbauerlawHardnessBeta-tricalcium phosphateMagnetic properties:NATURAL SCIENCES:Physics [Research Subject Categories]AnimalsElectron paramagnetic resonanceZebrafishFe3+ and Zn2+ co-substitutionRietveld refinementThermal decompositionTemperature021001 nanoscience & nanotechnology0104 chemical sciencesCrystallographyZincMechanics of MaterialsVickers hardness testsymbolsPowders0210 nano-technologyRaman spectroscopyMaterials Science and Engineering: C
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The influence of Fe3+ doping on thermally induced crystallization and phase evolution of amorphous calcium phosphate

2021

The present study investigates thermally induced crystallization and phase evolution of amorphous calcium phosphate (ACP) partially substituted with Fe3+ ions (M/P = 1.5 : 1). It was demonstrated that the presence of Fe3+ ions radically changes the crystallization behavior of ACP and completely prevents the formation of α-tricalcium phosphate (α-TCP, Ca3(PO4)2), which is the first crystalline phase obtained from non-substituted ACP upon thermal treatment. Surprisingly, calcium deficient hydroxyapatite (CDHA) was obtained instead of α-TCP. Such unusual crystallization behavior was observed with a doping level as low as 0.1 mol% with respect to Ca ions. Moreover, it was shown that the presenc…

chemistry.chemical_element02 engineering and technologyGeneral ChemistryThermal treatmentCalcium010402 general chemistry021001 nanoscience & nanotechnologyCondensed Matter PhysicsPhosphate01 natural sciences0104 chemical scienceslaw.inventionCrystallographychemistry.chemical_compoundchemistrylawPhase (matter)General Materials ScienceAmorphous calcium phosphateCrystallization0210 nano-technologyThermal analysisElectron paramagnetic resonanceCrystEngComm
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