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Bioagrotehničke metode u organskoj biljnoj proizvodnji
No full textMetode koje se primenjuju u organskoj proizvodnji su odavno poznate i njihova primena je u stalnom rastu, zbog čega se kao takve sve više usvajaju od strane šire poljoprivredne, ali i urbane zajednice. Pored fizičkih i mehaničkih mera i klasičnih agrotehničkih metoda, u prethodnom periodu se sve više koriste biološke i njihova kombinacija, tzv. bioagrotehničke metode (mere). Njihovom primenom može se lakše prilagoditi neizbežnim klimatskim promenama uz poštovanje i očuvanje biodiverziteta, održavanje kvaliteta zemljišta, poboljšanje uslova životne sredine, te zaštite zdravlja i dobrobiti ljudi i domaćih životinja, a u cilju da proizvedena hrana osigurava zdravlje i zaštitu životne sredine, kao i da po mogućstvu poseduje i visoki nutritivni kvalitet.
Posledice učestalog i neadekvatnog korišćenja agrohemikalija (pesticida i mineralnih ubriva), a pre svega zaga enje voda, vazduha i zemljišta, smanjena biološka aktivnost, smanjena mikrobiološka brojnost i aktivnost u zemljištu, te spora razgradnja plastika, više su nego zastrašujuće (Bao et al., 2024). Takav odnos može naštetiti prvo ciljanim, a potom i neciljanim biljkama, insektima, pticama, sisarima i vodozemcima, a u krajnoj meri divljim i domaćim životinjama, kao i ljudima. S tim u vezi, da bi se sačuvao ekosistem, preciznije agroekosistem, Evropska Кomisija je u decembru 2019. godine, usvojila Evropski zeleni plan i nekoliko strategija koje ure uju ovu oblast. Prva je Strategija Evropske unije za zemljište koja postavlja niz ambicioznih i neophodnih ciljeva za obnavljanje zemljišta u EU. Ova strategija se do 2030. godine u velikoj meri „oslanja“ na Evropski zeleni plan...http://polj.uns.ac.rs/sites/default/files/udzbenici/Monografija_Izazovi_i_trendovi.pd
Tehnološki postupak uvodjenja lanika (Camelina sativa L. Crantz) u organsku ratarsku proizvodnju
No full textPredloženo tehničko rešenje odnosi se na uvođenje lanika (Camelina sativa (L.) Crantz) u sistem organske ratarske proizvodnje kroz iznalaženje i razvoj optimalnog agrotehničkog modela. Cilj predloženog tehničkog rešenja bio je definisanje ključnih elemenata proizvodne prakse u skladu sa principima organske poljoprivrede, sa naglaskom na proširenje plodoreda, dugoročnu održivost proizvodnog sistema i povećanje agrobiodiverziteta. Posebna pažnja posvećuje se i obezbeđivanju zdravstveno bezbednih i visokokvalitetnih sirovina, što je od suštinskog značaja za organsku proizvodnju. Inovativnost predloženog tehničkog rešenja leži u činjenici da lanik u Srbiji nije do sada gajen u organskoj proizvodnji. Agrotehnički model koji je razvijen obuhvata sve faze proizvodnje, počev od određivanja optimalnog mesta lanika u plodoredu, preko izbora načina obrade zemljišta i adekvatne predsetvene pripreme, do preciziranja metoda i vremena setve. U okviru modela razmatraju se i mere nege useva koje su u skladu sa organskim standardima, kao i vreme i način žetve koji obezbeđuju očuvanje kvaliteta i prinos useva.
Uvođenje manje zastupljenih ili do sada nezastupljenih vrsta u Srbiji, kao što je lanik, u organsku poljoprivredu u potpunosti je u skladu sa evropskim strategijama koje promovišu prelaz ka raznovrsnijim, održivijim i ekološki prihvatljivijim sistemima proizvodnje hrane. Razvijanje metode proizvodnje lanika u organskoj proizvodnji predstavlja inovativan pristup jer uključuje prilagođene agrotehničke mere za novu vrstu, proširuje plodored u skladu sa principima održive poljoprivrede i nudi direktnu primenu u realnim uslovima organske proizvodnje.
Predloženo tehničko rešenje razvijano je na lokaciji Bački Petrovac, u uslovima organske proizvodnje tokom dve vegetacione sezone (2021/2022 i 2022/2023), na karbonatnom černozemu u dvopoljnom plodoredu sa pšenicom kao predusevom. Zemljišni i klimatski uslovi ovog lokaliteta veoma su slični uslovima u proizvodnji kod korisnika „SOYA FOOD ORGANIC“. Ogled je postavljen po metodologiji za ispitivanje sorti lanika radi priznavanja sorti, sa primenom organskih đubriva i konzervacijske obrade zemljišta i setvom visokokvalitetnog, netretiranog semena dve sorte lanika NS Slatka i NS Zlatka.
Prilikom razvoja tehnološkog postupka proizvodnje lanika u organskom sistemu, ispitivani su efekti sorte i roka setve na niz agroekonomskih i kvalitativnih parametara. Analizirani su prinos, visina biljke, broj bočnih grana, broj semena po biljci, masa semena po biljci, kao i sadržaj ulja i proteina u semenu. Dobijeni rezultati su statistički obrađeni primenom analize varijanse (ANOVA), uz procenu značajnosti razlika između tretmana, čime je obezbeđena pouzdanost u interpretaciji uticaja ispitivanih faktora.
Rezultati eksperimenta pokazali su značajne razlike između jesenje i prolećne setve, kao i razlike između sorti lanika tokom dve vegetacione sezone. U prvoj godini (2021/2022), prosečan prinos u jesenjoj setvi iznosio je 1493,25 kg/ha, a u drugoj godini (2022/2023) 1699,05 kg/ha. U jesenjoj setvi prve godine, NS Slatka je ostvarila prinos od 1682,5 kg ha-1, znatno veći u odnosu na NS Zlatku sa 1304,0 kg ha-1. Razlika je bila statistički značajna i prisutna i u broju semena po biljci (2251,25 naspram 1741,25 semena NS Slatka, odnosno NS Zlatka redom) i masi semena po biljci (2,15 g naspram 1,70 g NS Slatka, odnosno NS Zlatka redom). U drugoj godini u jesenjoj setvi, NS Slatka je ponovo dala veći prinos (1715,7 kg ha-1) u odnosu na NS Zlatku (1682,4 kg ha-1), ali razlika nije bila statistički značajna. Takođe je zabeležen viši sadržaj ulja kod NS Slatke (34,75%) u odnosu na NS Zlatku (32,89%), kao i veća masa semena po biljci (2,19 g naspram 2,18 g). U prolećnoj setvi, prinos je bio niži u obe godine u odnosu na jesenju setvu, ali su biljke bile više i imale su više bočnih grana. U drugoj godini u prolećnoj setvi, NS Slatka je ostvarila statistički značajno veći prinos (1482,6 kg ha-1) u odnosu na NS Zlatku (1366,7 kg ha-1), kao i viši sadržaj ulja (32,14% prema 29,21%). Sa druge strane, NS Zlatka je u prolećnoj setvi imala znatno veću visinu biljaka (91,17 cm) u odnosu na NS Slatku (83,83 cm). Sadržaj proteina u semenu nije značajno varirao u zavisnosti od vremena setve ili sorte u obe godine, što ukazuje na njegovu stabilnost kao parametra. Rezultati istraživanja naglašavaju važnost odabiranja odgovarajućeg vremena setve i sorte za postizanje optimalnih prinosa i kvaliteta u organskoj proizvodnji lanika.
Tehničko rešenje razvijeno za organskog proizvođača „SOYA FOOD ORGANIC“ pokazalo je da uvođenje lanika u dvopoljni plodored uspešno proširuje plodosmenu, unapređuje bidiverzitet i usklađuje je sa propisima organske proizvodnje. Zahvaljujući kratkom vegetacionom periodu, otpornosti na stresne uslove i efikasnosti u kontroli korova, lanik se pokazao kao ekonomično i agrotehnički opravdano rešenje. Dobijeni rezultati dodatno ističu značaj, aktuelnost i inovativnost tehnologije gajenja lanika u organskoj proizvodnji, jer otvaraju nove mogućnosti za obezbeđivanje zdravstveno bezbednih sirovina namenjenih proizvodnji visokokvalitetnog organskog ulja i drugih finalnih proizvoda
Formation of Pt/Ru Bimetallic Deposits on TiO2 Nanotube Arrays via Galvanic Displacement: Synergistic Interactions Enhancing Hydrogen Evolution Electrocatalysis
No full textProton exchange membrane water electrolysis powered by renewable energy offers a promising route for the high-rate production of ultrapure green hydrogen. However, large-scale commercialization hinges on the development of cost-effective and durable electrocatalysts for the hydrogen evolution reaction (HER) in acidic media. A widely adopted approach to reduce the platinum group metal (PGM) content and enhance mass activity involves immobilizing PGMs on conductive supports with high surface area. Our previous work demonstrated that galvanic deposition of monometallic PGMs on self-ordered TiO2 nanotube (TNT) arrays yields highly active HER catalysts with low PGM loading [1–4]. Here, we extend this strategy to synthesize bimetallic Pt/Ru deposits on nanograss-engineered, H-intercalated TNT arrays using both one-step and two-step galvanic displacement [5]. Simultaneous deposition produces alloyed Pt–Ru nanoclusters (<50 nm), while sequential Ru and Pt deposition yields ~5 nm Ru nanoparticles coated with polydisperse Pt deposits, including atomic islands and subnanometric shells as the dominant fraction. These Pt|Ru nanointerfaces facilitate strong electronic interactions, evidenced by charge
transfer from Pt to Ru. The Pt/Ru atomic ratio and the proportion of Pt surface sites in the composites are generally higher for the two-step procedure and increase with extended platinization time. The most active catalyst, Ru-30min@Pt-30min, balances the exposure of catalytically enhanced Pt|Ru interfaces with an abundance
of Pt sites. With ultralow loadings (10.4 μgRu cm–2 and 2.1 μgPt cm–2), it achieves a
HER overpotential of just 58 mV at 100 mA cm–2 in 1.0 M HClO4, and a PGM mass
activity of 19.9 A mg–1 at η = 80 mV, showing a 3.5-fold increase over a (Pt/C)/Ti disk.
Theoretical calculations confirm that Pt modification of Ru and hydrogenated TiO2
surfaces tunes the hydrogen adsorption free energy, creating a favorable energetic
landscape for fast HER kinetics in acidic environments
ZnO-nanostructured electrochemical sensor for efficient detection of glyphosate in water
No full textGlyphosate is a widely used broad-spectrum herbicide for controlling grassy weeds, despite having potential health hazards. Herein, we report on a solid-state electrochemical sensor based on ZnO nanoparticles (ZnO NPs) for on-site detection of glyphosate. Accordingly, ZnO NPs was drop-cast on the surface of a disposable screen-printed carbon electrode. Eco-friendly ZnO NPs of only 7 nm crystallite sizes were obtained by green sol-gel synthesis using lemon (Citrus limon) waste aqueous extract as the green reducing and capping/stabilizing agent and Zn nitrate precursor as evidenced by scanning electron microscopy (SEM), transmission electron
microscopy (TEM), X-ray diffraction and diffuse reflectance. SEM confirmed successful electrode functionalization with the synthesized nanoparticles. Under laboratory conditions in acetate buffer (pH 5), the sensor demonstrated excellent selectivity and sensitivity, with a detection limit of 0.648 μM, a wide linear detection range (0.5 μM to 7.5 mM), and a rapid detection time of 30 min. When tested in river water, the sensor achieved a detection limit of 0.96 μM using differential pulse voltammetry. It also exceptionally tolerated interference from similar organophosphorus compounds and ions commonly found in river water. The excellent detection performance of the sensor was attributed to the strong coordination interactions between Zn atoms and phosphonate/carboxylate groups that are enhanced by a hydrogen bond at acidic pH, as determined by chemical calculations. This disposable sensor offers a cost-effective, efficient, and environmentally friendly solution for monitoring glyphosate in water systems
The Influence of Bacterial Inoculants and a Biofertilizer on Maize Cultivation and the Associated Shift in Bacteriobiota During the Growing Season
No full textMaize (Zea mays L.) relies heavily on nitrogen and phosphorus inputs, typically
supplied through organic and inorganic fertilizers. However, excessive agrochemical
use threatens soil fertility and environmental health. Sustainable alternatives, such as
poultry manure (PM) and plant growth-promoting rhizobacteria (PGPR), offer promising
solutions. This study examines the effects of a phytobiotic bacterial formulation (PHY),
composed of Bacillus subtilis and Microbacterium sp., applied alone and in combination with
PM, on maize’s rhizosphere bacteriobiome across key growth stages. Field trials included
four treatments: a control, PHY-coated seeds, PM, and combined PHY_PM. The results
show that early in development, the PM-treated rhizospheres increased the abundance
of beneficial genera such as Sphingomonas, Microvirga, and Streptomyces, though levels
declined in later stages. The PHY_PM-treated roots in the seedling phase showed a reduced
abundance of taxa like Chryseobacterium, Pedobacter, Phyllobacterium, Sphingobacterium, and
Stenotrophomonas, but this effect did not persist. In the PM-treated roots, Flavisolibacter
was significantly enriched at harvesting. Overall, beneficial bacteria improved microbial
evenness, and the PHY_PM treatment promoted bacterial diversity and maize growth.
A genome analysis of the PHY strains revealed plant-beneficial traits, including nutrient
mobilization, stress resilience, and biocontrol potential. This study highlights the complementarity
of PM and PGPR, showing how their integration reshapes bacteriobiome and
correlates with plant parameters in sustainable agriculture
An Estimate of Penetration Depth of Rigid Rods Through Materials Susceptible to Microcracking: Part 1 - Theory
No full textThe present study proposes an approximate model focused on a simplified estimate of depth of penetration of rigid projectiles into quasibrittle solids. Penetration at normal incidence of a slender, rigid rod into massive targets, made of materials predisposed to microcracking due to their inferior tensile strength and heterogeneous structure, is an event characterized by a high level of aleatory variability and epistemic uncertainty. This inherent stochasticity is incorporated into a model developed based on particle dynamics simulations that provide the key modeling ingredient – an estimate of the radial traction necessary to dynamically expand a cylindrical cavity. The penetration depth expressions are derived for the conical and ogive nose projectiles. The related theoretical considerations for spherical nose projectiles are developed to the point where using the cylindrical cavity approximation becomes debatable. The novel use of the power-law radial traction dependence upon the expansion rate yields equations of penetration resistance and penetration depth defined in terms of hypergeometric functions. These expressions are readily evaluated by modern tools for technical computing
Physiological Performance of Poplar and Willow Clones Growing on Metal-Contaminated Landfills
No full textThis study evaluated the physiological responses and biomass production of selected poplar and willow clones cultivated in form of phytoremediation buffer plantations on landfills in Vinča (near Belgrade) and Novi Sad, Serbia. Key parameters assessed included net photosynthesis (A), transpiration (E), stomatal conductance (gs), and water use efficiency (WUE). Results indicated a significant Clone × Site interaction for net photosynthesis, suggesting environmental-specific clone responses. Transpiration and stomatal conductance exhibited site-stable expression between sites, implying conservative traits or similar hydrological conditions during measurements. Particularly, total site values for physiological parameters were higher at the Novi Sad site, likely due to continuous access of plants to groundwater. The weak correlation between WUE and biomass production suggests that favorable water conditions at both sites diminished the importance of water use efficiency for biomass accumulation. Poplar clone S1-8 exhibited the highest biomass production and leaf-level gas exchange traits (A, E, gs, WUE), reflecting a fast-growth strategy through increased gas exchange. This clone’s consistent productivity across sites classifies it as a generalist, while willow clone 378 and poplar clone 135/81, with significantly higher biomasses at the Novi Sad site than at the Vinča site, can be considered as specialists. Use of both generalist and specialist clones in multiclonal plantations may enhance phytoremediation and biomass production stability across variable sites. These findings underscore the importance of selecting appropriate clones for phytoremediation on landfills and on contaminated lands in general
Multifunctional reusable Ag-decorated ZnO nanostructured photocatalyst obtained by green synthesis
No full textThis work examined an environmentally friendly precipitation method for preparing zinc oxide decorated with silver using chitosan as a non-toxic reducing agent. The obtained powders were characterized in detail by XRPD, FESEM, HRTEM/SAED, PSD, and UV–VIS techniques. Ag/ZnO samples contained wurtzite spherical nanoparticles with an average crystallite size of about 25 nm and cubic Ag distributed on the surface. Compared to the unmodified ZnO, modification with Ag increased absorption of the visible light regarding the formation of additional charge carriers, i.e. hot electrons, due to the surface plasmon resonance effect. The recyclable Ag/ZnO photocatalyst with an optimal content of 1.5 mol. % of Ag, was successfully applied under simulated solar light for the degradation of four industrial dyes: Reactive Orange 16, Mordant Blue 9, Acid Green 25, and Ethyl Violet. High repeatability and reproducibility were confirmed. The kinetics and full mechanism of the photodegradation process through the simultaneous and synergistic influence of light-harvesting Ag and ZnO were also suggested
Possibility to use local ponded ash as supplementary cementitious material
No full textProduction of Portland cement, the main binder material used in construction, contributes to ~5% of global CO2 emissions. In order to reduce the negative environmental impact of cement production, cement producers and users adopted various strategies, mostly based on more extensive use of supplementary cementitious materials (SCMs) and reduction of cement clinker content in cements. This resulted in shortage of CEM I in markets and raised reasonable concerns about future availability of traditionally used SCMs, such as fly ash. On the other hand, more than 400 ha of arable land in Serbia are taken by landfills where fly ash produced by the local thermal power plants is already being disposed.
The aim of this work is development of sustainable low carbon footprint binder with low cement clinker content, in which a portion of CEM II is substituted by ponded fly ash (PA). Two PA samples from “Nikola Tesla” power plant were used: one recently disposed (sample from the active landfill, PAA), and the PA sample taken from the closed, passive, landfill (sample PAP). Mechanical activation was used as a method to improve properties of the PA samples and increase their content in the binder. It was found that up to 20 wt.% of mechanically activated PAA could be used as the cement substitute while maintaining excellent mechanical properties of the used CEM II, thus providing 52.5 MPa 28-days compressive strength. At the same time, binder samples that contained up to 30 wt.% of mechanically activated PAP showed good mechanical properties, and developed compressive strength higher than 42.5 MPa after 28 days of curing
Natural Sunlight Driven Photocatalytic Degradation of Methylene Blue and Rhodamine B over Nanocrystalline Zn2SnO4/SnO2
No full textThe natural sunlight driven photocatalytic degradation of organic pollutants is a sustainable
solution for water purification. The use of heterojunction nanocomposites in this process
shows promise for improved photodegradation efficiency. In this work, nanocrystalline
Zn2SnO4/SnO2 obtained by the solid-state synthesis method was tested as a heterojunction
photocatalyst material for the degradation of methylene blue (MB) and Rhodamine B
(RhB) dyes as single and multicomponent systems in natural sunlight. Characterization of
the structure and morphology of the synthesized nanocomposite using X-ray diffraction
(XRD), Fourier transform infrared spectroscopy (FTIR), field emission scanning electron
microscopy (FESEM), transmission electron microscopy (TEM) combined with energy
dispersive X-ray spectroscopy (EDS), and photoluminescence (PL) spectroscopy confirmed
the formation of Zn2SnO4/SnO2 and heterojunctions between Zn2SnO4 and the SnO2
nanoparticles. A photodegradation efficiency of 99.1% was achieved in 120 min with 50 mg
of the photocatalyst for the degradation of MB and 70.6% for the degradation of RhB under
the same conditions. In the multicomponent system, the degradation efficiency of 97.9% for
MB and 53.2% for RhB was obtained with only 15 mg of the photocatalyst. The degradation
of MB occurred through N-demethylation and the formation of azure intermediates and
degradation of RhB occurred through sequential deethylation and fragmentation of the
xanthene ring, both in single and multicomponent systems