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Preparation and Characterization of Hydroxyapatite-Modified Natural Zeolite: Application as Adsorbent for Ni2+ and Cr3+ Ion Removal from Aqueous Solutions
No full textNatural zeolites (NatZ) are widely available, porous, crystalline aluminosilicate minerals that are commonly used as cost-effective adsorbents in water treatment processes. Despite their efficiency in removing various heavy metal ions from wastewater, NatZ show relatively low affinity toward Ni2+ and Cr3+ ions. This study aimed to develop composite adsorbents based on NatZ and hydroxyapatite using two methods, hydrothermal and mechanochemical, and their adsorption properties for the removal of Ni2+ and Cr3+ ions from aqueous solutions were investigated. X-ray powder diffraction and scanning electron microscopy analyses confirmed that under hydrothermal conditions, needle-like hydroxyapatite crystals were formed on the surface of NatZ, while the zeolite structure remained unchanged. Compared to the mechanochemically prepared sample, this adsorbent showed higher efficiency, binding 6.91 mg Ni2+/g and 16.95 mg Cr3+/g. Adsorption kinetics of the tested cations in both cases can be described by a pseudo-second-order model (R2 is higher than 0.95 for all adsorbents). It is concluded that the presence of hydroxyapatite on the zeolite surface significantly improves the adsorption performance of NatZ, demonstrating its potential for the removal of heavy metal ions in wastewater treatment
Development of κ-Carrageenan/Gelatin pH-Responsive Hydrogels for Potential Skin Regeneration Application
No full textAdvanced skin care involves innovative, multifunctional, and bio-inspired biomaterials capable of regenerating skin tissue. Here, we report the facile route for the fabrication of the bio-sourced pH-responsive hydrogels based on κ-carrageenan and gelatin, with properties desirable for the treatment of versatile skin disorders. The extensive characterization revealed differences in physicochemical properties due to chemical modifications of the hydrogels. Porosity ranged from 21.67% to 95.81%. By modifying κ-carrageenan hydrogels with gelatin, the Young's modulus values increased proportionally with the gelatin content, ranging from 0.23 to 2.90 MPa, while native κ-carrageenan hydrogels had the lowest values (0.12–0.42 MPa) and native gelatin hydrogels had the highest (10.85–18.03 MPa). Native κ-carrageenan hydrogels exhibited the most pronounced swelling (18.6–27.0), followed by gelatin-modified κ-carrageenan hydrogels (6.5–23.0) and native gelatin hydrogels (7.8–9.0). The native κ-carrageenan hydrogels also displayed the highest water vapor transmission rate (WVTR) (259.99 ± 16–279.91 ± 19 g m−2 day−1), while the presence of gelatin lowered it. The hydrogels were preliminary exposed to human fibroblasts (MRC-5 cell line) and then to Caenorhabditis elegans to reveal the effects on whole living organisms. The summarized results suggest that the hydrogels represent advantageous and versatile biocompatible biomaterials set for further investigation as delivery platforms for bioactive molecules suitable for skin tissue regeneration
Pollen–Pistil Interactions in Autochthonous Balkan Sweet Cherry Cultivars—The Impact of Genotype and Flowering Temperature
No full textThe efficacy of sweet cherry production is highly dependent on the regularity of
flowering events and genetic-determined relations between female sporophyte and male
gametophyte, which became even more important with higher flowering temperatures
caused by climate change. Special attention is paid to the genetic diversity that provides
essential sources of potential temperature-tolerance genes. Our study aimed at the genetic
and reproductive characterization of Balkan cherry cultivars of autochthonous origin
(‘Canetova’, ‘G-2’, ‘Dolga Šiška’ and ‘Ohridska Crna’), and six potential pollinizers. To
identify S-haplotypes, the polymerase chain reaction (PCR) method was used to detect the
S-ribonuclease (S-RNase) and S-haplotype-specific F-box protein (SFB) alleles, combined
with fragment analysis and S-RNase sequencing. Pollination experiments were performed
at three Balkan localities over two flowering seasons, and the fluorescence microscopy
method was used to assess the cultivars’ male/female reproductive behaviour. A novel
S-RNase allele S40 was identified in ‘Ohridska Crna’ for the first time. ‘Ohridska Crna’
also demonstrated the best adaptability to higher temperatures regarding primary ovule
longevity. This feature makes it desirable from the aspect of breeding new cultivars that
can withstand the impacts of climate change. The findings on male-female relations and
their temperature dependence open up the possibility for yield prediction and smart
horticultural decisions that can be made to guide cherry production
Corrigendum to “Synthesis and properties of in situ prepared polyurethane/PEG-MXene nanocomposites” [Prog. Org. Coat. 203 (2025) 109158] (Progress in Organic Coatings (2025) 203, (S0300944025001079), (10.1016/j.porgcoat.2025.109158))
No full textThe authors regret: - CRediT authorship contribution statement Ivan Pešić: Writing – original draft, Investigation, Data curation, Visualization, Formal analysis. Jean-Olivier Durand: Investigation, Formal analysis, Data curation, Writing – review & editing. Dana Vasiljević Radović: Validation, Formal Analysis, Investigation, Data curation. Sanja Ostojić: Validation, Formal Analysis, Investigation, Writing – review & editing. Miloš Petrović: Investigation, Validation. Vesna Radojević: Investigation, Validation. Marko Spasenović: Writing – review & editing, Validation, Resources, Project administration, Investigation, Funding acquisition, Formal analysis, Data curation. Marija V. Pergal: Writing – original draft, Writing – review & editing, Visualization, Validation, Supervision, Project administration, Resources, Methodology, Investigation, Formal analysis, Data curation, Conceptualization, Funding acquisition.- Order of the corresponding authors should be changed at the bottom of the first page as follows: [email protected]; [email protected] authors would like to apologise for any inconvenience caused.Correction to: [https://doi.org/10.1016/j.porgcoat.2025.109158]Correction to: [https://technorep.tmf.bg.ac.rs/handle/123456789/8109
Tehničko-tehnološko rešenje solidifikacije i stabilizacije (S/S) odabranih vrsta industrijskog otpada generisanih radom postrojenja za livenje i mehaničku obradu delova za automobilsku industriju
No full textTehničko rešenje kategorije M82 – Novo tehničko rešenje (metoda) primenjeno na nacionalnom nivo
Device for increasing pressure in water supply systems with measurement of accumulated drinking water quality
No full textLow pressure in water supply systems, affecting both
residential and industrial facilities, is a common issue in water
distribution networks. Water sourced from municipal systems or
shallow wells can experience pressure fluctuations or even complete
drops, particularly during summer months. Supply from rooftop or
overflow reservoirs often fails to maintain sufficient pressure to
adequately supply all taps and appliances. Low pressure can also
disrupt household devices such as washing machines, dishwashers, and
water heaters. To address these problems, pressure-boosting systems are
installed, which include additional pumps connected inline with
pipelines or accumulation tanks for cases when water supply is
interrupted. +The simplest solutions involve hydrophore units (a booster
pump combined with a pressure vessel controlled by a pressure switch).
However, noise generated by water pipes or booster pumps can cause
discomfort for residents, often due to improper pump selection or
inadequate regulation. Older centrifugal pumps with fan-cooled motors
can create system-wide vibrations, increasing overall noise levels. This
paper presents a technical solution for a pressure-boosting device in water supply systems, featuring reservoirs, recirculation pumps, water
quality measurement systems, pressure-increasing pumps with PID
control, compact electronic pressure transmitters, and expansion tanks.
The design ensures silent operation while maintaining constant pressure
in the water supply network. The device has been installed and tested in
the Tonanti Hotel, Vrnjačka Banja, Serbia
Exploring the role of crude laccase from c. Trogii 2smkn in the biodegradation of brilliant green dye: impact of temperature and ph, phytotoxicity assessment and antimicrobial activity
No full textBrilliant Green dye is widely used in industries such as paper, textiles, rubber, and plastics,
primarily for dyeing wood and silk. However, it poses serious health risks, including toxicity
through skin and eye contact, ingestion, and inhalation, which can lead to organ damage if
exposure is prolonged. Therefore, the removal of Brilliant Green dye from water is an important
environmental concern. This study investigates the potential of crude laccase, extracted from the
white rot fungus Coriolopsis trogii 2SMKN, to biodegrade this harmful triphenylmethane dye.
The white rot fungus was cultivated on lignocellulosic agro-industrial waste (brewerʼs spent
grain) at 28°C in the dark for six days, producing crude laccase with a total activity of 31.43
IU/g. To test the dye decolorization efficiency, experiments were conducted at temperatures
ranging from 20°C to 50°C and pH values between 2.5 and 6.0. The best decolorization rate of
69% was achieved at pH 2.5 and 30°C after 90 min, while only 12% of decolorization was
observed at pH 6 and 50°C under the same conditions. After complete dye decolorization,
phytotoxicity tests were performed on Triticum aestivum, an agriculturally important crop. The
results showed a germination index of 102%, suggesting that the biodegradation products had a
phytostimulatory effect. In contrast, test of antimicrobial activity indicated that undegraded dye
inhibited the growth of Candida albicans and Lactobacillus rhamnosus by 42% and 30%,
respectively, while it had no effect on Saccharomyces cerevisiae. The biodegradation products,
however, did not inhibit any of the tested microorganisms. These findings indicate that crude
laccases from fungi, when optimal conditions are applied, can effectively decolorize Brilliant
Green dye in a relatively short period. Furthermore, the biodegradation products have potential
as phytostimulants, offering promising applications in agriculture. This study highlights the
utility of fungal enzymes in the bioremediation of harmful dyes, as well as their potential role in
promoting sustainable farming practices
Laboratories Accredited According to ISO/IEC 17025:2017 in the Science and Higher Education System
No full textKoličina proizvoda prisutnih na tržištu se iz dana u dan povećava, a jedan od ključnih faktora koji diktira opstanak na istom je kvalitet. Za širok spektar proizvoda postoje zakonom definisane minimalne performanse koje se moraju ispuniti u pogledu zaštite životne sredine i zdravlja ljudi. Ispitivanje ovih performansi vrši se u laboratorijama za ispitivanje, a ukol-iko su te laboratorije akreditovane prema standardu ISO/IEC 17025 rezulta-ti tih ispitivanja prihvaćeni su u celom svetu. Iako mnoge visokoškolske i naučno-istraživačke organizacije u svetu poseduju laboratorije za ispitivan-je i/ili laboratorije za etaloniranje u kojima se obavlja obrazovni i naučno-istraživačkim rad, samo mali broj njih je akreditovan prema standardu ISO/IEC 17025. Akreditacija laboratorija u okviru sistema nauke i visokog obrazovanja sa sobom donosi niz benefita poput prisustva velikog broja kvalifikovanih kadrova i razvoja akademskog preduzetništva. U okviru ovog rada izvršeno je ispitivanje korelacije između društveno-političkih faktora poput bruto društvenog proizvoda, broja stanovnika i broja studena-ta u državama bivše Jugoslavije sa brojem akreditovanih laboratorija za ispitivanje i etaloniranje u sistemu nauke i visokog obrazovanja. Nakon toga izvršena je analiza dodeljenih inicijalnih akreditacija i obima akreditacija u ovim laboratorijama. Rezultati su pokazali najveći korelacio-ni koeficijent između broja akreditovanih laboratorija u sistemu nauke i visokog obrazovanja sa brojem studenta, dok je udeo ovih laboratorija na fakultetima je iznosi 7,52% , dok je na naučnim insitutima ovaj udeo iznosi 8%The quantity of products available on the market is increasing daily, and quality is one of the key factors determining their survival. For a wide range of products, legally defined minimum performance requirements must be met concerning environmental protection and human health. The testing of these performances is conducted in testing laboratories, and if these laboratories are accredited according to the ISO/IEC 17025 standard, their test results are recognized worldwide. Although many higher education and scientific institutions have testing and/or calibration laboratories for educational and research purposes, only a small number of them are accredited under the ISO/IEC 17025 standard. The accreditation of laboratories within the science and higher education system offers numerous benefits, such as the presence of a large number of qualified personnel and the development of academic entrepreneurship. This study examines the correlation between socio-political factors—such as Gross Domestic Product (GDP), population size, and the number of students in the countries of the former Yugoslavia—and the number of accredited testing and calibration laboratories in the science and higher education system. Additionally, an analysis was conducted on the allocation of initial accreditations and the scope of accreditations in these laboratories. The results revealed the highest correlation coefficient between the number of accredited laboratories in the science and higher education system and the number of students. The share of these laboratories within universities is 7.52%, while in scientific institutes, this share amounts to 8
Advanced Approach towards Electrochemical Oxidation and Determination of Aripiprazole Using Gold and Boron-Doped Diamond Electrodes
No full textThe antipsychotic drug aripiprazole (ARP) can be determined at the trace level in biological samples employing an easy-to-use and
very sensitive electrochemical approach. The cyclic voltammetric behavior of ARP at the gold (Au) electrode and the boron-doped
diamond electrode (BDDE) was investigated and suggested that the ARP oxidation process is irreversible and adsorptioncontrolled.
The morphology of ARP on the Au electrode surface was studied using optical microscopy and atomic force
microscopy techniques. The various experimental parameters of the SW-AdSV method were optimized for the quantitative
determination of ARP at the anodically pretreated BDDE (+2.4 V; 60 s). Under optimized conditions (pH 3.0; accumulation
potential (Eacc) of 0.5 V and accumulation time (tacc) of 180 s), a linear concentration range was from 0.10 ng ml−1 to
16.91 ng ml−1, while the relative standard deviation did not exceed 4.6%, and the evaluated detection limit (LOD) was
0.03 ng ml−1. The interference study confirmed adequate selectivity of the proposed SW-AdSV method and BDDE towards ARP.
During the analysis of ARP in spiked urine sample, good recovery and reproducibility were achieved, suggesting a good
application capability and reliability of the developed voltammetric method for monitoring ARP in biological samples
Characterization and Thermodynamic Study of Sulfidation of Secondary Alkaline Lead Slag
No full textSecondary alkaline lead slag, a major byproduct of lead smelting and lead-acid battery recycling, contains both valuable metals (Pb, Zn, Cu, Sn) and toxic elements (As, Cr, Sb), posing considerable environmental challenges while offering opportunities for metal recovery. Efficient recycling of this slag is crucial for minimizing environmental risks and maximizing resource utilization. This study investigates the sulfidation process as a promising metallurgical approach to selectively recover valuable metals while stabilizing hazardous elements. The research includes the physical and chemical characterization of the secondary alkaline lead slag and a comprehensive thermodynamic analysis to assess its thermodynamic properties and behavior within the examined system. Thermodynamic modeling was performed using HSC Chemistry® ver. 10, optimized key process parameters, including temperature, sulfur addition, and potential additives, to enhance recovery efficiency. The physical characterization of lead slag included measurements of bulk density, moisture content, and granulometric composition, while elemental composition was analyzed using X-ray fluorescence spectrometry (XRF) and inductively coupled plasma optical emission spectrometry (ICP-OES). Phase composition was determined via X-ray diffraction (XRD), and slag morphology was examined using scanning electron microscopy (SEM). The thermodynamic analysis confirmed the feasibility and effectiveness of the lead slag sulfidation, demonstrating favorable conditions for selective metal recovery and the stabilization of hazardous components