Vinča Institute of Nuclear Sciences
Repository of the Vinča Institute of Nuclear Sciences (VinaR)Not a member yet
15953 research outputs found
Sort by
Spectroscopic and Morphological Properties of Co0.9Gd0.1MoO4 Nanopowders
No full textThe glycine nitrate procedure (GNP) stands out as the most effective and reliable method for controlling the composition and morphology during the synthesis of Co0.9Gd0.1MoO4 [1]. This combustion process ensures precise control over stoichiometry, homogeneity, and purity, allowing us to produce high- quality Co0.9Gd0.1MoO4 with confidence. We conducted a thorough analysis of the samples synthesized using this method, employing a range of advanced characterization techniques, including Differential Thermal Analysis (DTA), X-ray Diffraction (XRD), Fourier Transform Infrared Spectroscopy (FT-IR), Field Emission Scanning Electron Microscopy (FESEM), and nitrogen adsorption methods. The results revealed a high degree of anisotropy in the particles' shape and size, forming distinct agglomerates. Additionally, we observed significant differences in the microstructure, notably the development of well- defined plate-like crystals. Crucially, the color of the synthesized sample transformed from darker to lighter shades following thermal treatments. We also noted considerable changes in the dominant wavelength (in nanometers) and color purity between the initial sample and the sample heated to 1100 °C, primarily driven by variations in cobalt concentration. This highlights the effectiveness of the GNP in achieving controlled and reproducible synthesis outcomes.Advances in Solid State Physics and New Materials - 30 years of the Center for Solid State Physics and New Materials at the Institute of Physics Belgrade, 19 – 23 May 2025, Belgrade, Serbia
DFT Study of Glutamine (L) Interactions with Pristine and Au / Ag / Cu Doped TiO₂ Surfaces: Energy Landscape and Potential Biomedical Applications
No full textThis study connects inorganic and organic systems through a theoretical investigation of the energy landscape of a molecule–substrate interaction, focusing on glutamine (L) adsorbed on pristine and doped TiO₂ crystal modification, anatase, in a vacuum. We explored potential inorganic–organic interactions within these systems, depending on the properties of the TiO₂ material under investigation, which may have applications as a possible anticancer agent or nanoscale therapeutic. Glutamine was selected as the model molecule due to its important role in cancer metabolism—it serves as an alternative to glucose for fueling the tricarboxylic acid (TCA) cycle in cancer cells, with many tumor cells relying on extracellular glutamine for survival [1,2]. To simulate the interactions between nanoparticles and an amino acid molecule, we constructed systems with different glutamine conformations onto quasi-2D slab surfaces of anatase TiO₂, oriented along the (001) and (101) planes, both in their pristine form and doped with Au, Ag, or Cu. Ab initio calculations were performed using Density Functional Theory (DFT) with the LDA and GGA-PBE functionals, employing two different computational codes—CRYSTAL17 and Quantum Espresso [3]. Given the low symmetry and high atomic complexity of these systems, the calculations were computationally intensive and required substantial memory resources. To optimize the search for low-energy configurations of molecule on ceramic-type surfaces, we implemented an iterative approach that alternated between doped and undoped surfaces, which proved to be highly efficient for identifying stable structures in inorganic–organic systems of this nature. The most important result of this study might be that even without exposing the system to high temperatures or irradiation by high-energy photons, we find that just the simple adsorption process of glutamine on TiO2 surfaces can locally release enough energy to lead to a break-up of the molecule. Furthermore, by selecting different types of doping of the anatase substrate and varying the initial orientation of the molecule, this nanocrystalline material can be used for fine- tuning the physical and chemical interactions with the glutamine molecule or inducing a break-up of, or a dissociation of H atoms from the molecule (Figure 1), which provides important insights for future research and potential applications in biomedicine.Advances in Solid State Physics and New Materials - 30 years of the Center for Solid State Physics and New Materials at the Institute of Physics Belgrade, 19 – 23 May 2025, Belgrade, Serbia
Co/β zeolite for ORR in alkaline media
No full textOpen Readings 2025 : 68th international conference for students of Physics and Natural sciences : May 13th–16th, 2025, Vilnius, Lithuania
Nitrogen-doped graphene quantum dot-aromatic amino acid hybrids: synthesis, interface interactions, and photoluminescence properties
No full textNitrogen-doped graphene quantum dots (NGQDs) were synthesized through a straightforward and rapid hydrothermal method using citric acid and urea as precursors. The resulting NGQDs were non-covalently functionalized (conjugated) with aromatic amino acids, specifically phenylalanine (Phe) and tryptophan (Trp). Atomic force microscopy analysis revealed that the NGQDs exhibit a disk-like morphology, with an average diameter of approximately 60 nm and an average height of around 0.4 nm. Following conjugation, the height of the particles increased to approximately 3 nm. UV-vis spectroscopy confirmed the successful conjugation of the amino acids to the NGQD nanostructures. Density functional theory (DFT) numerical calculations were conducted using three different N-doped clusters to further investigate the nature of the non-covalent interactions between NGQDs and the respective amino acids. Photoluminescence spectra demonstrated stable and intense fluorescence signals for both hybrids in the UV region. The most significant changes were observed in the case of Trp conjugation. Unlike phenylalanine, the non-covalent bonding of tryptophan to NGQDs significantly influenced the visible emission at around 500 nm, which originates from the surface states of the quantum dots.18th Photonics Workshop : International conference; March 16-20, 2025; Kopaonik, Serbia
On compact topological edge modes in photonic ribbon lattices
No full textTopological insulation and the associated unidirectional propagation of edge modes have opened new avenues for light control, enabling the design of novel photonic devices with enhanced performance and stability [1]. The number of topologically protected edge modes, determined via the bulk-edge correspondence, is linked to changes in the bulk k- space Hamiltonian and is quantified by topological invariants such as the winding number (Zak phase) in 1D and Chern numbers in 2D systems. This framework inherently implies a nonzero band curvature. In contrast, flatband (dispersionless) systems offer a distinct route for light control by supporting highly compact localized modes (CLMs). While topological protection and flatband localization are typically considered opposing effects, their interplay can significantly enhance the robustness of edge modes. Recent studies have demonstrated the existence of compact topologically protected modes [2,3]. Here, we systematically analyze this phenomenon in quasi-1D ribbon photonic lattices, considering four graphene-like ribbon configurations where the band curvature can be tuned by introducing an artificial magnetic flux in specific plaquettes. We investigate the emergence of compact topological edge modes in the presence of ribbon symmetries and geometric constraints. Additionally, we examine the robustness of CLMs against disorder and nonlinear effects and identify optimal lattice configurations for device design. Initial experimental efforts in realizing SP states [2], provide promising confirmation of our approach.18th Photonics Workshop : International conference; March 16-20, 2025; Kopaonik, Serbia
European metrology network for radiation protection: Quality infrastructure for a stronger Europe
No full textTo better protect European citizens, the EU's radiation protection regulations have become increasingly more sophisticated. Innovative technological developments and new threats can lead to new radiation exposure scenarios. Measures to respond to these new needs come by regulation and include for example increasingly restrictive exposure limits, the introduction of new reference values, and enhanced quality assurance requirements for legal dose assessment. Can metrology support the increasing needs laid down by regulation and ensure by this that Europe has a world-leading metrology capability, based on high-quality scientific research and an effective and inclusive infrastructure, that meets the rapidly advancing needs of end users? To do this, EURAMET has set up European Metrology Networks (EMN). Currently there are twelve EMNs: Advanced Manufacturing, Clean Energy, Climate and Ocean Observation, Energy Gases, Laboratory Medicine, Mathematics and Statistics, Pollution Monitoring, Quantum Technologies, Radiation Protection, Safe and Sustainable Food, Smart Electricity Grids and Smart Specialisation in Northern Europe. The European Metrology Network for Radiation Protection (EMN RP) responds to the technical developments and aims to act as a single point of contact to cover the metrological needs related to radiation protection. To enable quality assurance in all areas, the network fosters a harmonised, sustainable, coordinated and smartly specialised infrastructure to underpin the needs expressed by stakeholders and in the European regulations for radiation protection. This includes the close cooperation with organisations that are key in the international work for radiation protection like IAEA and ICRP or key for metrology like BIPM with CCRI and EURAMET with TC-IR. A special focus of the EMN is a cooperation with regulators and standardization bodies to actively contribute to the generation of new and to the revision of existing standards (ISO, IEC and CEN/CENELEC). The aim of the network is to support quality management in all radiation protection issues, to support the development of more harmonised service procedures and capabilities, analyse the needs and give support to research, and by this to contribute to the improvement of radiation protection as a whole. By doing so, the EMN for Radiation Protection improves the understanding of general metrology aims: quality assurance, quality of data and low uncertainties in measurements. The EMN for Radiation Protection presents within this contribution a research agenda designed to ensure that suitable reference fields and standards can be developed to support radiation protection regulations, to address knowledge transfer requirements and to provide input to international standards. Based on the possibilities offered by European funding programmes (Euratom and Horizon Europe), the EMN members propose joint research projects with the intention to develop solutions suitable for practical applications, develop new calibration services and facilitate the launch of new technologies. © 2025Part of special issue Proceedings of the XXIV IMEKO World Congres
Temperature-dependent photoluminescence of the synthesized Sb2S3 particles: From nanoparticles to crystalline samples
No full textThis research paper examines the findings of a study on temperature-dependent photoluminescence (TDPL) for various synthesized samples of the semiconductor Sb2S3 with different sizes. The samples include different sizes of nanoparticles and crystalline Sb2S3. TDPL is a powerful optical characterization method that provides valuable information about the quality of the synthesized material for potential application in photovoltaic solar cells. Despite its limited research, this semiconductor exhibits potential for use in solar cell applications. The study detected broad photoluminescence (PL) emission at a low temperature of 4 K, and it disappeared at higher temperatures in larger synthesized nanoparticles of at least 100 nm, as well as in the crystalline sample. However, the study recorded the PL spectrum for nanoparticles around 10 nm at both low (4 K) and room temperature, highlighting the significance of particle size in solar cell materials. These findings have implications for various applications and contribute to the understanding of carrier transport and localized states in semiconductor-synthesized materials. © 2025 Elsevier B.V
High-entropy spinel oxides: Self-propagating synthesis and densification by spark plasma sintering
No full textThe self-propagating room temperature method was utilized to synthesize high-entropy spinel oxides (HESOs): (Co,Cr,Fe,Mn,Ni)3O4-δ, (Mg,Cr,Fe,Mn,Ni)3O4-δ, (Mg,Co,Fe,Cr,Mn)3O4-δ, (Mn,Zn,Fe,Ni,Cr)3O4-δ, and (Co,Mn,Zn,Fe,Cr)3O4-δ. After thermal treatment at 1000 °C, XRD analysis confirmed their single-phased spinel structure. Densification by spark plasma sintering was successfully used for the first time on HESOs, resulting in relative densities from 94 % to 99 % while retaining the spinel structure. SEM/EDS mapping displayed a homogenous, dense microstructure with minimal porosity. (Mn,Zn,Fe,Ni,Cr)3O4-δ displayed the highest bending strength (171.5 MPa) and Young’s modulus (188 GPa). (Mg,Co,Fe,Cr,Mn)3O4-δ demonstrated the highest hardness (8.8 GPa), while (Mg,Cr,Fe,Mn,Ni)3O4-δ exhibited the highest indentation fracture toughness (1.5 MPa m–1/2). The lowest thermal diffusivity (0.67 – 0.51 mm2 s–1) was recorded for (Co,Mn,Zn,Fe,Cr)3O4-δ, while (Co,Cr,Fe,Mn,Ni)3O4-δ, had the highest thermal diffusivity (0.82 – 0.58 mm2 s–1). The study demonstrated a simple and efficacious method of synthesizing and densifying HESOs with structural, mechanical, and thermal properties favourable for different applications
The catalytic effect of cobalt and influence of mechanical milling on hydrogen storage system MgH2 – Co using small milling time
No full textThe addition of cobalt to MgH₂ powder and forming MgH₂ - Co composites was investigated for small milling times. The composite powders were synthesized for 15, 30, and 45 min and characterized by XRD, SEM-EDS, PSD, DSC, and TPD methods. During TPD analysis, a kinetic model for the hydrogen desorption process was also determined. The hydrogen desorption reaction in catalyzed samples is described by the Avrami-Erofeev model with the value of parameter n=4. The Ea (apparent activation energy) for the hydrogen desorption reaction was decreased with the increase in milling time and the addition of transition metal. The uniform distribution of transition metal decreases hydrogen desorption temperature by more than 100 °C compared to the pure MgH₂ and purely milled MgH₂. The quantity ratio of released hydrogen reached the highest value (LT/HT=3.38) for a sample with the highest amount (20 wt.%) of additive and the longest milling time (45 min). LT maxima appear at 310 °C, significantly reducing desorption temperature compared to commercial MgH₂ (480 °C). The short milling times improve desorption properties by lowering the hydrogen desorption temperature enhancing the effect of catalyst. In this approach, mechanosynthesis can be analyzed as two independent processes—grinding and catalytic effects. For the studied milling times, the catalytic influence of Co is dominant in the hydrogen desorption process.FEMS EUROMAT 2025 : 18th European Congress and Exhibition on Advanced Materials and Processes : 14-18 September 2025, Granada, Spain
Comparative assessment of PM2.5 data from remote satellite observations and by the low-cost sensor network in Serbia
No full textFine particulate matter (PM2.5) can harm human health, so it’s important to monitor its levels in large cities
where air quality is often poor[1]. Typically, national and government agencies use ground-based networks to
track PM2.5 concentrations. However, these networks don’t always cover all areas well, especially in
less-developed countries [2], leading to gaps in data and long periods without air quality measurements. Recent
advances in satellite technology and affordable air quality sensors offer new ways to fill these gaps [3].
Satellites can measure aerosol optical depth (AOD), which helps estimate PM2.5 levels and improve the
coverage of ground-based observations. Researchers have developed various statistical models, including
machine learning and geographically and temporally weighted regression [4], to better understand the link
between AOD and PM2.5 concentrations.
In this study, we have combined data from three sources: data from a low-cost sensor network [5] deployed at
12 locations in 4 cities in Serbia, satellite data from ECMWF/CAMS/NRT and
MODIS/006/MCD19A2_GRANULES with spatial resolutions 44528 m and 1000 m, respectively, and data
obtained from the Serbian Environment Protection Agency (SEPA) [6], for the period May 2022 to June 2023.
The results indicate different correlation between satellite data and low-cost sensor data for different sites, but
at most of the sites the best correlation is observed in the summer and in the winter periods.
This study will contribute to the ability to assess PM2.5 concentrations by alternative methods (satellite and
low-cost sensors) in regions with limited reference ground-based monitoring.Dept. of Earth and Geoenvironmental Sciences, 1-4 July, 2025, Bari, Italy