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Copyright © 2020, Springer Science Business Media, LLC, part of Springer Nature ; In this study, yttrium aluminium garnet (YAG) specimens in which yttrium was partially substituted by lanthanum Y3-xLaxAl5O12 (YLaAG) were prepared by an aqueous sol-gel method. YLaAG samples were analyzed by X-ray diffraction (XRD), solid state nuclear magnetic resonance (NMR) and electron paramagnetic resonance (EPR) methods. The presence of Ce3+ ions as an impurity originating from starting material was determined, therefore, luminescence measurements of YLaAG samples were also recorded. It was demonstrated that luminescent properties are strongly dependent on the phase composition of synthesized species. The XRD analysis results showed that only low substitution of yttrium by lanthanum is possible in Y3-xLaxAl5O12 without destroying garnet crystal structure. It was also demonstrated, that solid state NMR and EPR methods are indispensable tools for the explanation of processes and properties observed in the newly synthesized Y3-xLaxAl5O12 compounds. --- / / / --- This is the preprint version of the following article: Laurikenas, A., Sakalauskas, D., Marsalka, A. et al. Investigation of lanthanum substitution effects in yttrium aluminium garnet: importance of solid state NMR and EPR methods. J Sol-Gel Sci Technol (2020). https://doi.org/10.1007/s10971-020-05445-2, which has been published in final form at https://link.springer.com/article/10.1007/s10971-020-05445-2. This article may be used for non-commercial purposes in accordance with Springer Terms and Conditions for Sharing and Self-Archiving. ; This work was supported by a Research grant NEGEMAT (No. S-MIP-19-59) from the Research Council of Lithuania. 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.

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. ; In this work, a series of Mn2+-doped α-tricalcium phosphate (α-TCP) powders was synthesized by wet co-precipitation method followed by high-temperature annealing and thermal quenching. It was shown that Mn2+-doped α-TCP polymorph can be successfully synthesized with a doping level up to 1 mol%. All Mn-doped samples exhibited a broadband emission in the range from 525 to 825 nm with a maximum centered at around 630 nm. The highest emission intensity was observed for the sample with the highest content of Mn. The crystal structure and purity were evaluated by powder X-ray diffraction (XRD), Fourier-transform infrared (FTIR) and electron paramagnetic resonance (EPR) spectroscopies. Scanning electron microscopy (SEM) was used to investigate the morphological features of the synthesized products. Optical properties were investigated by means of photoluminescence measurements. Excitation spectra, emission spectra and decay curves of the samples were studied. Temperature-dependent photoluminescence measurements were performed as well. --- / / / --- This is the preprint version of the following article: Lauryna Sinusaite, Andris Antuzevics, Anatoli I. Popov, Uldis Rogulis, Martynas Misevicius, Arturas Katelnikovas, Aivaras Kareiva, Aleksej Zarkov, Synthesis and luminescent properties of Mn-doped alpha-tricalcium phosphate, Ceramics International 47 (4) (2021), https://doi.org/10.1016/j.ceramint.2020.10.114, which has been published in final form at https://www.sciencedirect.com/science/article/pii/S0272884220331540. This article may be used for non-commercial purposes in accordance with Elsevier Terms and Conditions for Sharing and Self-Archiving. This work is licensed under a CC BY-NC-ND 4.0 license. ; European Social Fund 09.3.3-LMT-K-712-19-0069; 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 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). ; Interest in magnetic nanoparticles is primarily due to their practical use. In this work, for the production of nanocrystalline powders of pure and gadolinium doped iron oxides, the extraction-pyrolytic method (EPM) was used. As a precursor, either iron-containing extract (iron (III) caproate in caproic acid) or its mixture with gadolinium-containing extract (gadolinium (III) valerate in valeric acid) was used. The mixed precursor contained 0.5 mol %, 2.5 mol %, 12.5 mol %, 50 mol %, and 75 mol % gadolinium in relation to the iron content. The formation of iron oxide phases, depending on the preparation conditions, was investigated. According to the results obtained, it was demonstrated that the presence of more than 2.5 mol % gadolinium additive in the mixed precursor inhibits the magnetite-to-hematite transformation process during thermal treatment. Produced samples were characterized by XRD and SEM methods, and the magnetic properties were studied. ; H2020 Marie Sklodowska-Curie grant agreement No. 778070; Latvian Science Council project lzp-2018/1-0214; Estonian Research Council grant (PUT PRG619); 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

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. ; In the present work, Fe3+ and Zn2+ co-substituted β-tricalcium phosphate (β-TCP) has been synthesized by wet co-precipitation method. Co-substitution level in the range from 1 to 5 mol% has been studied. Thermal decomposition of as-prepared precipitates was shown to be affected by introducing of foreign ions, decreasing the decomposition temperature of precursor. It was determined that partial substitution of Ca2+ by Fe3+ and Zn2+ ions leads to the change in lattice parameters, which gradually decrease as doping level increases. Lattice distortion was also confirmed by means of Raman spectroscopy, which showed gradual change of the peaks shape in the Raman spectra. Rietveld refinement and electron paramagnetic resonance study confirmed that Fe3+ ions occupy only one Ca crystallographic site until Fe3+ and Zn2+ substitution level reaches 5 mol%. All co-substituted samples revealed paramagnetic behavior, magnetization of powders was determined to be linearly dependent on concentration of Fe3+ ions. Cytotoxicity of the synthesized species was estimated by in vivo assay using zebrafish (Danio rerio) and revealed non-toxic nature of the samples. Preparation of ceramic bodies from the powders was performed, however the results obtained on Vickers hardness of the ceramics did not show improvement in mechanical properties induced by co-substitution. --- / / / --- This is the preprint version of the following article: Lauryna Sinusaite, Anton Popov, Andris Antuzevics, Kestutis Mazeika, Dalis Baltrunas, Jen-Chang Yang, Jiun Lin Horng, Shengfang Shi, Tohru Sekino, Kunio Ishikawa, Aivaras Kareiva, Aleksej Zarkov, Fe and Zn co-substituted beta-tricalcium phosphate (β-TCP): Synthesis, structural, magnetic, mechanical and biological properties, Materials Science and Engineering: C 112, 110918 (2020), https://doi.org/10.1016/j.msec.2020.110918, which has been published in final form at https://www.sciencedirect.com/science/article/abs/pii/S0928493119344285#!. This article may be used for non-commercial purposes in accordance with Elsevier Terms and Conditions for Sharing and Self-Archiving. This work is licensed under a CC BY-NC-ND license. ; European Social Fund under the No. 09.3.3- LMT-K-712; 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.