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Comparative mineralogical analysis of two zeolitic tuff Slanci and Zlatokop
No full textThe paper presents the comparative results of quantitative X-ray powder analysis and cation exchange
capacity for zeolitic tuffs Slanci and Zlatokop. The basic mineral composition is represented by Caclinoptilolite
(Zlatokop) and Ca-heulandite (Slanci), feldspars, quartz and clay appear as accompanying
components. The X-ray powder diffraction method on a polycrystalline sample and the Sirquant software
program were used to determine the quantitative composition
High-temperature mechanical response of Co-free non-equiatomic CrMnFeNi alloy
No full textThe equiatomic Cantor alloy CrMnFeCoNi is considered a reference high-entropy alloy due of its high
strength, radiation resistance, and thermal stability, and suitability for structural applications. However, cobalt, which is added to stabilize the FCC phase and improve strength, produces long-lived radioactive isotopes
under neutron irradiation and limits its use in nuclear systems. For this reason, development of Co-free alloys
has become important. In this study, we investigated the non-equiatomic Cr15Mn13Fe39Ni33 alloy, designed
within the INNUMAT project as a candidate for nuclear applications. The aim was to examine its mechanical behavior in the temperature range 25–700 °C using a combination
of experiments and molecular dynamics simulations. Tensile tests, SEM-EBSD, and XRD were applied to
characterize phase stability, texture, and microstructure evolution. In parallel, atomistic simulations were used
to follow dislocation activity, stacking fault formation, and twinning, and to compare the response of single- and polycrystals with experimental observations. Results show that strength decreases with temperature due to thermally activated mechanisms and
microstructural changes. Both experiments and simulations indicate the presence of stacking faults, twins, and
grain boundary activity, with strong dependence on grain orientation ([111] grains soften gradually, while
[110] grains lose strength rapidly above 550°C). The chemical design of the alloy, with no Co and higher Ni, raises the stacking fault energy and changes deformation mechanisms compared to the Cantor alloy. Despite
the compositional complexity, Schmid’s law remains valid in describing slip activity and anisotropic
deformation. The study confirms that Co-free HEAs are suitable for structural applications in nuclear environments by
showing that they have favorable mechanical properties at high temperatures in addition to radiation
resistance
Application of sustainable fertilizers: biochar and phosphate glass effects at rose flowering
No full textControlled release fertilizers (CRF) provide nutrients that dissolve gradually, remaining available to plants longer than conventional fertilizers. This study investigates the influence of phosphate glass and biochar, as prospective controlled-release fertilizers, on the growth and development of rose seedlings. Biochar is the product of thermochemical conversion of biomass, where organic substances are thermally broken down at specific process parameters, in a reduced oxygen atmosphere. Phosphate glass (45.4P₂O₅·25.6K₂O·14.5CaO·3.1SiO₂·9.3MgO·1.2ZnO·0.9MnO) was synthesized from reagent grade materials by melting at 1230 °C for 1 h in a porcelain crucible and quenching on steel. Different dosages of plum stone biochar (PS) and phosphate glass (PG) were tested on rose plantings. The addition of PS and PG had no significant influence on the number of branches, but higher doses (3 g of PG and 10 g of PS) favored flower formation. Chemical analysis at the end of the cycle showed increased phosphorus and manganese in all samples, higher zinc with 2 g PG, and elevated calcium in all variants. Overall, addition of PG and PSB to the soil samples improved rose growth
Phytoremediation potential of metallophytes in Europe: Progress, enhancement strategies, and biomass utilization
No full textPhytoremediation is a plant-driven process, widely regarded as a cost-effective and environmentally friendly in
situ approach for remediating contaminated soil and water by taking up contaminants including potentially toxic
elements (PTEs). In the last two decades, substantial research has focused on elucidating the mechanisms of
phytoremediation and enhancing its efficiency, primarily through the identification of optimal plant species and
the use of various amendments. Nevertheless, real-scale application of phytoremediation remains rare, and
several critical questions need to be addressed, including selection of most effective species, improved effec-
tiveness of phytoremediation process, and managing the safe utilisation of contaminated biomass. This review
specifically focuses on phytoremediation of potentially toxic metals and metalloids in major metallophyte groups
(wild herbaceous species, trees, and agricultural crops) recognizing the most efficient species for the anthro-
pogenically influenced soils in Europe. It summarises the current state of knowledge regarding the use of
respective plant species, highlighting the phytoremediation efficiency, critically examining existing and novel
phytoremediation enhancement strategies and biomass utilisation pathways for each particular group. Future
perspectives and research needed to refine the efficiency and economic viability of the phytoremediation process
in Europe lay in better recognition of underlying physiological mechanism for metal stress tolerance, particularly
among the most effective species and genera, application of synergistic enhancing techniques for delineated
group of metallophytes and development of sustainable and cost-effective biomass utilisation routes
Role of the local diffusion fields in electrolytic formation of zinc irregular forms from the alkaline electrolyte
No full textThe alkaline electrolytes are a component of Zn-air secondary batteries, representing promising candidate for energy storage with numerous advantages relative to the other battery types, such as Li-air, Al-air, and Mg-air. One of the largest challenge in a development of this battery type is a formation of irregular forms of nanostructured characteristics during the charging process, such as dendrites, irregular and regular crystal grains of various shape including those having hexagonal shapes. The formation and growth of all these forms occur in conditions of the diffusion control of the electrodeposition process, and while a mechanism of formation and growth of dendrites is relatively well investigated, it is not case with a mechanism of a growth of crystal grains, especially those with a hexagonal shape. For that reason, this study aims to investigate it.
The growth of the hexagonal grains formed in the moment of nucleation inside the diffusion layer of the macroelectrode depends on their orientation towards bulk of the electrolyte. These grains can be oriented towards the bulk of electrolyte by either the tip or lateral side, and the local diffusion fields, such as the spherical and cylindrical ones, formed around their tips or the lateral sides are responsible for their final shape. The spherical diffusion layer is formed around the tip of hexagonal crystal grain oriented by the tip towards the bulk of the electrolyte and Zn crystals of elongated shape are formed in the growth process. The cylindrical diffusion layer is formed around the lateral side of hexagonal Zn crystal oriented by the lateral side towards the bulk of electrolyte, and this orientation of Zn grain survives the growth process. Mathematical model has been developed to show that the rate of growth in the conditions of the spherical diffusion is larger than that in the conditions of the cylindrical diffusion, that is confirmed by morphological analysis of Zn crystal grains obtained with various times of the electrodeposition
Experimental analysis of exposed concrete slabs through image analysis
No full textThe paper presents a comparative analysis of eight concrete slabs prepared under
laboratory conditions. The slabs were cast using formwork of varying quality, cured for 1 and 7
days, and compacted for 7s and 10 s. The comparison of properties, specifically the pore surface
area of different diameters, was conducted using image analysis software. The results show that
curing conditions had no significant effect on the surface characteristics of exposed concrete, while
both the type of formwork and compaction duration demonstrated a more significant influence
Characterization and Evaluation of Biomass Waste Biochar for Turfgrass Growing Medium Enhancement in a Pot Experiment
No full textThe sustainable management of urban grasslands is crucial for resilient city ecosystems.
With increasing urbanization, improving soil quality to support turfgrass growth has
become a priority. This study evaluates biochar produced from Paulownia leaves (PLB),
a low-cost byproduct of Paulownia cultivation, as a growing medium amendment. Raw
leaves (PL) and PLB were characterized by SEM, FTIR, and elemental analysis to assess
physicochemical changes. A three-month pot experiment under outdoor conditions was
conducted with turfgrass plots exposed to different irrigation and fertilization regimes.
Growing medium pH, moisture, electrical conductivity, cation exchange capacity, nutrient
availability, grass chlorophyll content, and uptake were monitored. The application of PLB
improved the growing medium structure, raised the pH by up to one unit, and enhanced
pigment accumulation in turfgrass samples. When combined with nitrogen fertilizer, PLB
significantly increased turfgrass visual quality, whereas under limited irrigation, PLB
alone improved seedling establishment compared to controls. Statistical analysis confirmed
significant treatment effects by ANOVA, and PCA provided a precise classification of treatment
groups. These findings indicate that PLB can improve nutrient efficiency, turfgrass
resilience, and organic waste management
Rudničke vode: Uticaj na životnu sredinu i inovativne metode tretmana
No full textRudarstvo i metalurgija su industrije koje imaju značajnu ulogu u globalnoj ekonomiji. Sa druge strane, prilikom rudarskih aktivnosti proizvode se značajne količine otpadnih voda. Njihovo nekontrolisano ispuštanje može imati veoma negativan uticaj na životnu sredinu i zdravlje ljudi, usled visokog sadržaja teških metala, sulfata i drugih zagađujućih materija, kao i niske pH vrednosti. U ovom radu analizaran je uticaj otpadnih voda iz rudarskih aktivnosti na vodu, zemljište i zdravlje ljudi i prikazane su neke od novih tehnologija koje se koriste za njihov tretman. Alternativni adsorbenti, poput pirinčane ljuske, zeolita, kukuruzne stabljike, komposta od hrane i čelične šljake, pokazali su efikasnost u uklanjanju teških metala, nudeći ekonomičnu i održivu alternativu tretmana. U radu su predstavljene četiri tehnologije (SAVMIN®, SPARRO®, Biogeni H2S i DESALX®) koje su već u primeni na većim skalama i koje su se pokazale veoma uspešnim i ekonomičnim. Pored toga, prikazan je predlog jedne inovativne i obećavajuće metode, koja kombinuje fizičke, biološke i mikrobiološke procese za efikasniji tretman ovih voda
Obtaining organo-zeolite by surface modification
No full textThe aim of this work was to investigate the influence of dodigen concentration on the formation of organo-zeolite. In this work, organo-zeolite was successfully obtained
with different concentrations of dodigen and it was shown that the modification reaction takes place by the mechanism of cation exchange.Cilj ovog rada bio je da se ispita uticaj koncentracije dodigena na građenje
organo-zeolita.U radu je upešno dobijen organo-zeolit pri različitim koncentracijama dodigena
i pokazano je da se reakcija modifikacije odvija mehanizmom katjonske izmene
Determination of the morphology of TiO2 particles obtained by green synthesis using waste biomass
No full textNanoparticles have become essential in diverse applications, notably in photocatalysis and wastewater treatment. The morphology of photocatalytic materials significantly influences their efficiency. In this study titanium dioxide (TiO₂) nanoparticles were synthesized using mandarin peel extract via a green chemistry approach, offering a simple, cost-effective, and eco-friendly alternative to conventional methods of synthesis. The main focus was on the morphological characterization of the synthesized TiO₂ nanoparticles using scanning electron microscopy (SEM) coupled with energy dispersive X-ray spectroscopy (EDS). SEM analysis revealed rod-shaped particles with sizes ranging from 120 to 260 nm, uniformly distributed and aggregated across the sample. This morphology is favorable for photocatalytic applications due to increased surface area. EDS confirmed the elemental composition, indicating the successful formation of TiO₂. The study highlights the potential of agrowaste-based synthesis for producing functional nanomaterials with applications in photocatalysis and wastewater treatment