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Primena fosfatnih stakala kao đubriva u proizvodnji cveća-agristakla AglasJ2 i AglasA2
No full textAgristakla predstvljaju inovativni oblik đubriva koja hranljive materije otpuštaju postepeno, u skladu sa potrebama biljke. Za razliku od tradicionalnih đubriva, ona smanjuju gubitke hranljivih materija ispiranjem i isparavanjem. Time se povećava iskorišćenost đubriva i smanjuje potreba za čestom prihranom. Njihova upotreba pozitivno utiče na zemljište jer sprečava zakiseljavanje i prekomerno zaslanjivanje. Takođe, smanjuje se opasnost odzagađenja podzemnih i površinskih voda nitratima i fosfatima. Na taj način agristakla doprinose održivoj poljoprivredi i očuvanju životne sredine. Cilj ovog tehničkog rešenja je da dizajnira tehnološki postupak za dobijanje novih, korisnih materijala-agristakala, AglasJ2 i AglasA2, i da proceni efikasnost njihove primene kao đubriva sa kontrolisanim rastvaranjem u proizvodnji različitih vrsta cveća. Tehničkim rešenjem definisani su sastavi agristakala, optimizovano je njihovo dobijanje, stakla su fizički i hemijski (sa aspekta hemijske postojanosti u neutralnoj i kiseloj sredini) okarakterisana. Prikazani su uticaji oba agristakla na rast i razvijenost dve vrste cveća (kadifice i ruža) i definisane su preporučene doze. Sumiranjem rezultata može se zaključiti da se primenom agristakala, AglasJ2 i AglasA2,povećava usvajanje neophodnih biogenih elemenata od strane biljaka jer su lako dostupni i ne dolazi do zakiseljavanja zemljišta. Time direktno utiču na povećanje estetske vrednosti cveća, odnosno na njihovu tržišnu vrednost. Ispitivana agristakla, kao nova ekološka đubriva,pokazala su se veoma efikasnim u proizvodnji rasada cveća i sadnica ruža, te bi njihova komercijalna primena mogla biti visoko konkurentna u odnosu na postojeća spororazlagajuća đubriva i đubriva sa kontrolisanim rastvaranjem
Diffusion Models Of Drug Released In Poly(Vinyl Alcohol)/Chitosan/Gentamicin Hydrogels
No full textThe aim of this work was to synthesize and characterize the poly(vinyl
alcohol)/chitosan/gentamicin (PVA/CHI/Gent) hydrogel aimed for wound dressing
and to predict diffusion behaviour using novel General fractional derivative
model (GFD). The PVA/CHI/Gent hydrogel was prepared by physical cross
linking of poly(vinyl alcohol)/chitosan dispersion using freezing-thawing method,
then swollen for 48 h in gentamicin solution at 37oC, and characterized by
FE-SEM and FTIR. The concentration of released gentamicin was determined
using a high-performance liquid chromatography (HPLC) coupled with mass
spectrometry (MS). The experimental gentamicin release profile verified the initial
burst release effect, i.e. 60 % loaded antibiotic was released within first 48
h which could be very useful in preventing biofilm formation, followed by slow
release of gentamicin in a later time period. Diffusion mechanism of gentamicin
release was studied by comparison of novel GFD and Korsmeyer-Peppas,
Makoid-Banakar and Kopcha diffusion models. It was proven that our novel
diffusion GFD model better fitted with experimental data, and enabled the determination
of diffusion coefficient precisely for the entire time period
Bridging policy gaps through ISO 59000 standards in European waste management transitions
No full textThe European Union faces significant challenges in meeting its 2025-2035 circular economy targets, with 18 member states at risk of missing municipal waste recycling goals. This paper examines how the newly published ISO 59000 standards family (ISO 59004, ISO 59010, and ISO 59020) addresses these implementation gaps. By analyzing the standards’ requirements and obligations, this paper examines the potential to harmonize measurement methodologies, facilitate value network transitions, and establish transparent circularity performance indicators across diverse organizational contexts. The findings show that the standards focus on systems thinking, resource traceability, and core indicators, and that they provide practical solutions to the current deficiencies in European waste management. The paper contributes to closing the gap between theory and practice in circular economy implementation by mapping specific standard provisions to EU policy challenges and identifying potential implementation barriers that require policy attention and organizational capacity-building
Evaluating the human health risk from consuming plants growing in the metal(loid)-contaminated mine waste site
No full textThe area of the Bor mining complex is considered to be one of the most polluted areas in Serbia. Long-term mine activities left historical pollution and significant amounts of deposited mine wastes. The old mine tailing site in Bor was formed by applying non-selective disposal of extracted rocks, resulting in heterogeneity of physico-chemical conditions that hindered the full development of vegetation coverage.
In order to assess the health risk of As, Cd, Co, Cu, Mn, Ni, Pb, and Zn transfer to biota and further by the consumption at given area, their concentration from plant rhizosphere area of soils developed on three main distinguished lithological groups present at the old mine tailing site (andesite-A, altered andesite – AA, and fine-grained material – FM) is accessed. The plant bioavailable fraction of metal(loid) is considered to be a more reliable parameter for indirect health risk assessment by biota consumption than total metal(loid) concentration [1]. The non-carcinogenic (THQ) and carcinogenic (CR) risks were determined for consuming a biota grown on the investigated soil, based on the plant bioavailable soil fraction (Na2EDTA extracted). The indirect models for biota consumption assessment based on the soil concentration have been developed by the U.S. Department of Energy (DOE), Oak Ridge Operations Office (RAIS). Results show that THQsum risks exceeded 1 for soils from all investigated lithological groups (median values: THQsumA=29.02, THQsumAA=2.94 and THQsumFM=3.53), indicating the existing non-carcinogenic risk during long-term consumption of plants grown on the investigated sites. Additionally, carcinogenic risk to biota is present for all investigated sites as CR >1 × 10-6 (median values: CRsumA= 0.0023, CRsumAA= 0.00018, and CrsumFM= 0.00018).
Results of health risk assessments applied to biota consumption in this area may be used in the decision-making process for evaluating the adequate reclamation route and for decision-making when switching to selective waste disposal practices. In this case, due to the increased health risk at all main lithological groups present at the investigation site, agricultural reclamation route involving growing of different plant categories for human and cattle consumption, such as crops, palatable and medicinal plants, should be avoided prior to soil remediation or use of metal-accumulating plants for lowering the soil metal(loid) content in this area
Luminescent Multi-Iron Oxide Composite for Efficient Photocatalytic Decontamination of a Broad Spectrum of Pollutants in Aqueous Solutions
No full textWater contamination caused by both organic compounds and microbiological agents represents a persistent global challenge, urging the development of advanced, efficient, and environmentally friendly treatment technologies. Recent research highlights significant progress in iron oxide-based photocatalysts for water treatment applications, owing to their abundance, non-toxicity, and tunable optical properties [1,2]. Despite these advantages, challenges such as limited charge separation and suboptimal visible-light absorption remain key obstacles to their broader implementation [3]. In this study, we report the synthesis, characterization, and photocatalytic performance of a novel luminescent multi-iron oxide (LMIO) composite engineered for the broad-spectrum degradation of pollutants in aqueous solutions. The LMIO composite was synthesized via a precipitation route followed by thermal treatment, resulting in a nanostructured material with high surface area and strong light responsiveness. Comprehensive structural and optical analyses (XRD, FTIR, FESEM-EDS, PL) confirmed the successful integration of multiple iron oxide phases and luminescent centers, which facilitate enhanced charge separation and extended light absorption. Photocatalytic experiments under light irradiation demonstrated nearly 100% degradation of representative organic dyes (methylene blue and brilliant green), alongside complete inactivation of common wastewater pathogens (Staphylococcus aureus). The composite exhibited high stability and reusability over repeated cycles, underscoring its potential for real-world
applications. The superior performance of the LMIO composite is attributed to the synergistic interaction between its iron oxide phases and photoluminescent sites, leading to efficient generation of reactive oxygen species (ROS) and rapid pollutant breakdown. These findings establish LMIO as a promising multifunctional photocatalyst for sustainable water purification, capable of simultaneously eliminating chemical and biological contaminants
Influence of local factors on the deposition of pleistocene alluvial sediments in the lower Sava river valley
No full textThe Quaternary period was characterized by cyclic climate change, with alternating cold and warm stages. A case study of the alluvial sediments at water supply wellfield of the City of Belgrade shows how climate change has influenced the formation of alluvial sediments in the riparian area of the Sava River (Sava River ditch, in the southeastern part of the Pannonian Basin). A stratigraphic analysis of the Quaternary sediments of two boreholes on the location a BGS water well is presented in the paper, along with the methods, results, indications and hypotheses about their origin and the characteristics of the strata in the context of Pleistocene climate change and the local tectonic setting. The results indicate that alluvial sedimentation and the characteristics of these sediments are predominantly determined by the tectonic and geological setting, as well as local conditions of the area surrounding the object locations, supported by lateral streams and tributaries
Green synthesis of CuFe2O4 nanoparticles from bioresource extracts and their applications in different areas: a review
No full textIn this review, copper ferrite (CuFe2O4) nanoparticles (NPs) have attracted interest due to their unique properties and potential applications in biomedicine, environmental remediation, energy storage, and catalysis. The fabrication of CuFe2O4 NPs using green synthesis method has gained attention as an eco-friendly alternative to conventional synthesis methods. We have provided a critical evaluation and comparison of the applications of CuFe2O4 NPs fabricated by the green synthesis method using bioresource extracts of such as plant, bacteria, fungi, virus, and algae. We highlight the advantages of using green synthesis methods, including reduced toxicity, lower energy consumption, and decreased environmental impact. We also discuss the challenges associated with the synthesis of CuFe2O4 NPs using bioresource extracts and provide future perspectives for the use of green synthesis methods in this area. This review aims to provide insights into the applications of CuFe2O4 NPs fabricated by the green synthesis method and to guide future research in this area
The edaphic factor and orchids: Gymnadenia conopsea from contrasting geologies in the Central Balkans
No full textEdaphic stress is one of the main factors affecting plant fitness, but it is still poorly understood, even in rare plants such as orchids. Gymnadenia conopsea is a terrestrial orchid that grows on different geological substrates, making it a model species for the study of adaptive responses to edaphic factors, including metals in soil. The samples of plant tissues of G. conopsea growing on carbonate, ultramafic and siliceous substrates in Serbia and the associated rhizosphere soil were collected and analysed for elemental concentrations. Two different strategies for the distribution of macro- and trace elements were found, corresponding to the trend generally observed in orchids. Trace elements (As, B, Cr, Co, Fe, Mn, and Ni) remain mainly in the underground organs and only a small proportion is transferred to the shoots. It was the opposite for the macroelements (Ca, Mg, K and P) with the highest accumulation occurred in the leaves and inflorescences. The tolerance of G. conopsea to the different geological substrates results from the moderate metal concentrations in the soils analysed and the exclusion strategy of the species, which is the most common response to metal induced stress in orchids
Comparative Analysis of Cystine and Cysteine as Green Corrosion Inhibitors of Aluminium Alloy AA7075-T6
No full textCystine and cysteine as green corrosion inhibitors of the 7075 aluminium alloy in 0.1 M NaCl solution were analysed and compared. The inhibitive efficiency of the inhibitors was analysed by applying linear polarization resistance (LPR) and electrochemical impedance spectroscopy (EIS) methods. Different concentrations of both inhibitors in NaCl solution were tested under different temperatures and times to determine the corrosion kinetic and thermodynamic parameters. Optical microscopy (OM) and scanning electron microscopy (SEM) were used for analysis of the aluminium alloy surface before and after the electrochemical measurements. The hydrophilicity of the alloy surface with tested inhibitors was compared by applying contact angle measurements. The results showed that cystine and cysteine are effective corrosion inhibitors, with different characteristics and duration of protection on the tested aluminium alloy. Cysteine showed better efficiency for short-term applications while cystine provided more stable protection over a longer period