Vinča Institute of Nuclear Sciences
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Sintered magnesium ferrite particles in decolorization of anthraquinone dye AV109: Combination of adsorption and fenton process
No full textMagnesium ferrite (MgFe2O4) particles were synthetized by sol-gel method and used in the decolorization of the Acid Violet 109 (anthraquinone dye, AV109) water solutions' by combination of adsorption and heterogeneous Fenton process. The material's morphology and elemental analysis of the surface were revealed by Scanning electron microscopy and Energy Dispersive Spectroscopy (SEM/EDS). The X-Ray Diffraction (XRD) technique was used to analyze the crystallographic phase. In the first part of the decolorization experiment, the adsorption ability of the synthesized particles was investigated. During the adsorption study influence of pH was investigated. In the second part of the decolorization experiment, the effects of the various parameters on the Fenton process were studied such as the initial concentrations of hydrogen peroxide, dye, and magnesium ferrite particles. Influence of magnesium ferrite particles structure, pH value and reaction temperature were also investigated. The decolorization reaction was followed by UV-Visible (UV-Vis) spectrophotometry. At optimal conditions, the dye decolorization was 99.1% (55.4% by adsorption and 43.7% by the Fenton process). Both the adsorption and the Fenton process obey second-order kinetics.Честице магниезујум ферита (MgFe2O4) су синтетисане сол-гел методом и коришћене су за обезбојавање воденог раствора антрахинонске боје Кисело љубичасто 109 коришћењем адсорпције и хетерогеног Фентон процеса. Морфологија материјала и елементарна анализа површине испитана је скенирајућом електронском микроскопијом и енергодисперзионом спектроскопијом (SEM/EDS). Техником рендгенске дифракције праха (XRD) извршена је кристсалографска анализа материјала. У првом делу испитивања обезбојавања, испитана је способност адсорпције коришћењем синстетисаних честица. Током испитивања ефикасности адсорпције, испитан је утицај pH вредности. У другом делу експеримента, испитан је утицај више параметара на ефикасност Фентон процеса као што су почетна концентрација водоник пероксида, боје и магнезијум ферита. Такође, испитан је и утицај структуре честица магнезијум ферита, pH вредности и температуре реакције. Обезбојавање је праћено УВ-Видљивом (UV-Vis) спектрофотометријом. При оптималним условима, ефикасност обезбојавања је износила 99.1% (55.4% адсорпцијом и 43.7% Фентон процесом). Резултати адсорпције и Фентон процеса одговарају кинетичком моделу другог реда
Synthesis and characterization of Cu(II)‑meso-HMPAO complex as a model for the development of potential 64Cu radiopharmaceutical
No full textIn this work, Cu(II) complexes with meso‑HMPAO and d,l-HMPAO were synthesized. The structural characterisation of the isolated compounds has been done by single-crystal X-ray diffraction analysis, FTIR, and mass spectroscopy. Redox properties of complexes and binding to deoxyribonucleic acid (DNA) molecule have been analysed in detail by cyclic voltammetry and DFT calculations. The results of cyclic voltammetry fully agree with the data obtained by DFT calculations and indicate that the first electron removal takes place from the metal, while the second electron is removed from the ligand. The formation of the complex leads to the shift in oxidation peaks of the ligand from ‒0.29 V to 0,47 V and from 1.18 V to 1,24 V, indicating that ligand in the complex is much more difficult to oxidize. Electrochemical data confirmed the binding between the complex and DNA molecules through guanine. DFT calculations show that the complex is suitable not only for binding purine and pyrimidine bases through a coordination bond but also for additional hydrogen and CH-π interactions of the bases with the ligand. The fluorescence titration experiments revealed a moderate binding affinity of the [Cu-HMPAO]ClO4 complex to human serum albumin (HSA). Molecular docking revealed that this ligand preferentially binds to drug binding site 3 of HSA. Therefore, the novel compounds could be of great interest for further investigation, considering the potential anticancer activity, and as a model for the development of radiopharmaceutical with 64Cu.Peer-reviewed manuscript: [https://vinar.vin.bg.ac.rs/handle/123456789/14983
A novel Co/Zn-ferrite molecularly imprinted polymer-based electrochemical assay for sensing of gallic acid in plant extracts, wine, and herbal supplement
No full textIn this study, a new molecularly imprinted polymer (MIP)–based sensor platform was developed for the electrochemical determination of gallic acid (GAL) in plant extracts, wine, and herbal supplements. Gallic acid is known for its natural antioxidant properties, which play an important role in preventing cell deterioration that can lead to various diseases. In addition, gallic acid has therapeutic potential due to its anticancer, antiinflammatory, antimicrobial, and neuroprotective properties. Accurate analysis of gallic acid in complex matrices, in mixed samples where different components coexist, is necessary to evaluate the efficacy and safety of this compound. Cobalt ferrite-zinc-dihydro caffeic acid (CFO_Zn_DHCA) nanoparticles, sphere-like in shape and 5 ± 1 nm in size, were incorporated into the MIP-based electrochemical sensor design to enhance the active surface area and porosity of the glassy carbon electrode (GCE) surface. The functional monomer chosen for this study was aminophenyl boronic acid (3-APBA). In the GAL/CFO_Zn_DHCA/3-APBA@MIP-GCE sensor, which was developed using photopolymerization (PP), 3-APBA as a functional monomer was designed, and obtained in the presence of basic monomer (HEMA), cross-linker (EGDMA), and initiator (2-hydroxy-2-methyl propiophenone) by keeping it under a UV lamp at 365 nm. It aims to detect GAL in real samples such as Punica granatum (pomegranate) peel, Camellia sinensis (green and black tea leaves), wine, and herbal supplements. Morphological and electrochemical characterizations of the designed GAL/CFO_Zn_DHCA/3-APBA@MIP-GCE sensor were carried out using scanning electron microscopy (SEM), cyclic voltammetry (CV), and electrochemical impedance spectroscopy (EIS). The linear range for the determination of GAL using the indirect method (5.0 mM [Fe(CN)6]−3/−4) was found to be 1.0 × 10−13 M-1.0 × 10−12 M, and the limit of detection (LOD) and limit of quantification (LOQ) for standard solutions were calculated as 1.29 × 10−14 and 4.29 × 10−14 M, respectively. As a result of the study, the developed MIP-based electrochemical sensor was suitable for detecting GAL with high specificity, selectivity, and sensitivity. Recovery studies were performed to determine the practical applicability of the sensor, and the results were satisfactory. This innovative sensor platform stands out as a reliable and sensitive analytical tool for determining GAL
Methods of Zonal Model Application in Numerical Simulations †
No full textThis paper describes the recent attempts to apply the zonal model of thermal radiation in numerical simulations of pulverized coal-fired furnaces. Three methods are described: temporary correction of the total exchange areas (TCTEA), repeated run of the numerical simulation (RRNS), and current correction of the total exchange areas (CCTEA). The TCTEA and RRNS methods are based on successive runs of the numerical simulation. The CCTEA method is proof that the zonal model can be used in numerical simulations by the correction of the total exchange areas on the basis of current and initialized surface zone emissivity
Corrosion stability and biological activity of anodized cpTi for dental application
No full textThe anodic oxidation of titanium implants is a practical, cost-effective method to enhance implant success, especially due to rising hypersensitivity concerns. This study investigated the electrochemical behavior, surface characteristics, and biocompatibility of anodized commercially pure titanium (cpTi, grade IV). Anodization is performed on polished, cleaned cpTi sheet samples in 1 M H2SO4 using a constant voltage of 15 V for 15 and 45 min. The color of the oxide layer is evaluated using the CIELab color space, while composition is analyzed by a scanning electron microscope (SEM) equipped with an energy dispersive spectrometer (EDS). Additionally, X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) are performed to identify and monitor the phase transformations of the formed titanium oxides. Corrosion measurements are performed in 9 g L−1 NaCl, pH = 7.4, and show the excellent corrosion stability of the anodized samples in comparison with pure titanium. The biological response is assessed by determining mitochondrial activity and gene expression in human fibroblasts. Anodized surfaces, particularly Ti-45, promote higher mitochondrial activity and the upregulation of adhesion-related genes (N-cadherin and Vimentin) in human gingival fibroblasts, indicating improved biocompatibility and the potential for enhanced early soft tissue integration
Co/β zeolite for OER in alkaline media
No full textIntroduction A three-dimensional intersecting channel system called a zeolite β consists of pores and channels built from TO4 (T = Si, Al) tetrahedral units. Zeolites are porous crystalline solids with a large surface area that could be treated by unique cation exchange [1–3]. Zeolite-modified electrodes (ZMEs) attract huge attention for electrocatalytic and electroanalytical purposes. Here, we present ion-exchanged β zeolite with cobalt (Co/β) examined for oxygen evolution reaction (OER) in alkaline media. Methods Here presented Co/β zeolite was characterized by scanning electron microscopy with energy dispersive spectroscopy (SEM-EDS) and tested by linear sweep voltammetry (LSV) at 20 mV s-1 at 1800 rpm in 1 M KOH solution. All potentials given here are converted vs. reversible hydrogen electrode (RHE). Discussion Figure 1. clearly shows that Co/β zeolite is highly active for OER with a current density of 23 mA cm-2 at 2 V. This value is almost three times higher than Ce-β with 7.3 mA cm-2 [1]. 1.66 V was noticed for the onset potential (Eonset) at 1 mA cm-2 with an overpotential at Eonset of 460 mV (ηonset). Approximate values are obtained for similar zeolite OER electrocatalysts [1–3]. The Tafel slope of 93 mV dec-1 was calculated for Co/β which is significantly lower than the Tafel slopes obtained for similar zeolite OER electrocatalysts [1–3]. Conclusion Here examined Co/β zeolite for OER in alkaline media shows promising kinetics parameters and could be applied as a potential candidate for electrochemical energy conversion and storage devices, such as unitized regenerative fuel cells (URFCs) and metal-air batteries (MABs).The 24th biennial conference EcoBalt2025 : Octoberv 8-10, Vilnius, Lithuania
Intercomparison of professional and domestic radon devices
No full textU radu je prikazana interkomparacija između profesionalnih radonskih detektora: RTM1688-2, RAD7, RadonScout Professional i ugljenih kanistera kod kojih je data merna nesigurnost, jeftinijih detektora za kućnu upotrebu: 3 Corentium Home i ViewPlus i uređaja RadonEye koji je nešto između. Aktivni detektori su izlagani 7 dana u realnim uslovima u radnoj prostoriji Instituta za nuklearne nauke “Vinča”, dok su ugljeni kanistri u tom periodu izlagani 2 puta po 2 dana. Visok stepen Pearson-ove korelacije od 0,75 do 0,92, između RTM1688-2, RAD7, RadonScout Professional i RadonEye detektora koji su merili koncentracije radona na svakih sat vremena, ukazuje da pomenuta 4 detektora dobro prate varijaciju radona u zatvorenim prostorijama tokom vremena. Interkomparacija je vršena 2 puta u periodu od dva dana, kada su rezultati svih 9 detektora bili dostupni. Testom za autlajere je utvđeno da nema atipičnih rezultata merenja i svi detektori su iskorišćeni pri proceni robustne srednje vrednosti. Z - testom je utvrđeno da ne postoji statistički značajna razlika između srednje vrednosti koncentracije radona dobijene za svaki detektor ponaosob i referentne srednje vrednosti, i da se jeftini radonski uređaji za kućnu upotrebu mogu koristiti za merenje dvodnevne prosečne koncentracije radona.In this paper intercomparison between different classes of radon devices is presented. For professional radon detectors were considered RTM1688-2, RAD7, RadonScout Professional and charcoal canisters, which gave measurement uncertainty, and cheaper detectors declared by producesr for domestic usage: 3 Corentium Home devices and one ViewPlus device and the RadonEye device which is something in between. The active detectors, that have sampling time set for 1 hour, were exposed for 7 days in real conditions in the working room of the Institute of Nuclear Sciences Vinča , while the charcoal canisters were exposed two times for 2 days within the same 7 days period. The high values of Pearson's correlation coefficient, ranging from 0.75 to 0.92, between the RTM1688-2, RAD7, RadonScout Professional and RadonEye detectors that measured hourly radon concentrations, indicate that all detectors nicely follow a radon diurnal (hourly) variation. The intercomparison was performed two times over a period of two days, when the results of all 9 detectors were available. The test for outliers found that there were no extreme measured values and thus all detectors were used in the estimation of the robust mean value. With the ζ and Z tests, it was determined that there is no statistically significant difference between the mean value of the radon concentration obtained for each individual detector and the reference mean value, concluding that low cost radon devices could be used for measurement of two days average radon concentration.XXXIII симпозијум ДЗЗСЦГ [Друштва за заштиту од зрачења Србије и Црне Горе] : 1-3. октобар 2025. године
Preliminary results of testing the SMRZ-M23 scintillation survey meter prototype with a 0.4 L NaI(Tl) detector
No full textU radu je opisan prototip scintilacionog merača radioaktivnog zračenja SMRZ-M23 sa detektorom NaI(Tl) zapremine 0,4 L. Prikazani su rezultati ispitivanja linearnosti odziva detektora na polja zračenja izvora Cs-137 i Co-60, kao i energetski odziv na zračenje izvora Co-60, Ba-133 i Ra-226. Ispitana je i osetljivost detekcije izvora Ra-226. Uređaj se uspešno može koristiti za detekciju izvora gama zračenja zbog svoje visoke osetljivosti koja je oko 660 puta viša od detektora baziranih na Gajger-Milerovim brojačima. Takođe, njime je moguće mapiranje jačine doze zračenja zbog ugrađene interne memorije, a može biti i stacionarni merač priključivanjem na računar uz pomoć korišćenja razvijenog softvera.Dosimetry properties of the scintillation detector-based survey meter prototype SMRZ-M23 are presented. The dosimeter utilizes a NaI(Tl) detector with a volume of 0.4 L. Response linearity in the Cs-137 and Co-60 reference radiation fields, as well as the energy response to Co-60, Ba-133 and Ra-226 sources, are presented. The sensitivity of the Ra-226 source detection was also tested. The device can be successfully used for detecting radiation sources due to its high sensitivity, which is about 660 times higher than detectors based on Geiger-Müller detectors. It can also be used for mapping radiation dose rates due to its internal memory and as a stationary meter by connecting it to a computer using the developed software.XXXIII симпозијум ДЗЗСЦГ [Друштва за заштиту од зрачења Србије и Црне Горе] : 1-3. октобар 2025. године
Terahertz quantum cascade laser modeling for applications in imaging, sensing, and metrology
No full textIn the talk we present our recent modeling results for THz frequency QCLs including electronic structure and transport calculations of exemplary GaAs-based devices, investigation of alternative material platforms based on wide-bandgap semiconductors, modeling passive mode-locking with saturable absorber, and study of optical feedback effects. Moreover, we employ a machine learning framework for THz QCL design optimization. Methods include a Schrödinger-Poisson solver for calculating eigenenergies and wave functions, a density matrix carrier transport model, Maxwell-Bloch equations for passive mode-locking and self-mixing dynamics, and a multi-layer perceptron neural network to predict the laser transition figure of merit
Zelene inovacije za zdraviju i održiviju budućnost kroz projekat VIVENDI
No full textThree-quarters of cancer-fighting agents in medical use are derived from natural sources. However, their extraction from biomass requires significant quantities of volatile and toxic organic solvents, posing substantial risks to human health and the environment. Additionally, these bioactive compounds (BACs) often exhibit low bioavailability after administration, insolubility in water, and instability. Addressing these challenges, the Vivendi project (Green Innovation: Unlocking the Bioactive Potential of Biomass for Enhanced Pharmaceuticals and Foods through Eco-Friendly Sustainable Technologies), under the call Dijaspora2023, addresses these challenges by developing an integrated, eco-friendly extraction and formulation strategy that replaces conventional solvents with sustainable alternatives and enhances BAC stability through micellar encapsulation. A novel liquid–solid membrane extraction process, employing a membrane micromixer, has been applied for the first time to simultaneously isolate and micellize target compounds. Two model systems are investigated: (i) one-step extraction of BAC from raspberry using bio-based ionic liquids and natural deep eutectic solvents, and (ii) extraction of parthenolide from feverfew using an aqueous biphasic system formed with biocompatible Pluronic-type biopolymers and bio-based ionic liquids. To further improve stability, BACs are microencapsulated using different encapsulation techniques (spray and freeze-drying, and Lego-Inspired Microfluidic encapsulation), using different biopolymers, and thoroughly characterized with advanced analytical techniques. The knowledge generated within the VIVENDI project will enable the valorization of biomass and herbal residues, reduce industrial waste, and establish a novel, cost-effective green technology for BAC isolation and preservation, leveraging the multidisciplinary expertise of the VIVENDI consortium members.Tri četvrtine lekova koji se koriste u borbi protiv kancera potiču iz prirodnih izvora. Međutim, njihova ekstrakcija iz biomase zahteva upotrebu isparljivih i toksičnih organskih rastvarača, što predstavlja značajan rizik po zdravlje ljudi i životnu sredinu. Pored toga, bioaktivna jedinjenja (BAC) često imaju nisku bioraspoloživost, slabu rastvorljivost u vodi i nestabilnost. Projekat VIVENDI (Green Innovation: Unlocking the Bioactive Potential of Biomass for Enhanced Pharmaceuticals and Foods through Eco-Friendly Sustainable Technologies), koji se realizuje u okviru poziva Dijaspora2023, razvija integrisanu, ekološki prihvatljivu strategiju ekstrakcije i formulacije. Ova strategija zamenjuje konvencionalne rastvarače održivim alternativama i povećava stabilnost BAC jedinjenja primenom micelarne enkapsulacije. Po prvi put se primenjuje novi proces tečno–čvrsto membranske ekstrakcije, koji koristi membranski mikromikser za simultanu izolaciju (ekstrakciju) i micelizaciju ciljnih bioaktivnih jedinjenja. Ispituju se dva model sistema: (i) jednostepena ekstrakcija bioaktivnih jedinjenja iz otpada maline korišćenjem bio-baziranih jonskih tečnosti i prirodnih dubokih eutektičkih rastvarača; i (ii) ekstrakcija partenolida iz Tanacetum parthenium L. pomoću vodenog bifaznog sistema formiranog biokompatibilnim biopolimerima tipa Pluronic i bio-baziranim jonskim tečnostima. Stečena znanja tokom realizacije ovog projekta omogućiće valorizaciju biomase i biljnih ostataka nakon prerade, smanjenje industrijskog otpada i razvoj nove, isplative zelene tehnologije za izolaciju i očuvanje bioaktivnih jedinjenja, uz oslanjanje na multidisciplinarnu ekspertizu članova VIVENDI konzorcijuma.Poster: [https://vinar.vin.bg.ac.rs/handle/123456789/16167