Synthesis and optimization of new sorbents on the basis of oxide materials for removal of arsenic

Kontaminacija pijaće vode arsenom predstavlja jedan od najvećih ekoloških problema današnjice. Svetska Zdravstvena Organizacija je 1993. godine donela preporuku da koncentracija arsena u vodi za piće ne bude veća od 10 μg/L. Kao jedna od najbolje raspoloživih tehnika za smanjenje koncentracije arsena iz voda izdvojila se sorpcija. U prvom delu ove doktorske disertacije ispitan je efekat hemijske modifikacije komercijalno dostupnih sorbenata (BIRM, MGS i MTM) na efikasnost sorpcije arsena. Hemijskom modifikacijom titanom i cirkonijumom povećan je kapacitet sorpcije BIRM-a, modifikacijom titanom povećan je sorpcioni kapacitet MTM-a, dok hemijska modifikacija MGS nije uticala na sorpcioni kapacitet. MTM modifikovan titanom je uspešno uklonio As(III) ili As(V) početne koncentracije 0.2 mg/L u pH opsegu od 5 do 8 na vrednost ispod preporučene od strane Svetske Zdravstvene Organizacije. U drugom delu rada mehano-hemijskom reakcijom sintetisani su sorbenti na bazi MnO2, Fe2O3 i smeše Fe2O3:MnO2 u masenom odnosu 3:1. Ispitivanjem zavisnosti kapaciteta sorpcije od vremena trajanja mehano-hemijske sinteze, utvrđeno je da za MnO2 i Fe2O3 sa povećanjem vremena mehano-hemijske sinteze dolazi do povećanja kapaciteta sorpcije arsena. Pri mehano-hemijskoj sintezi materijala sa smešom Fe2O3:MnO2 u masenom odnosu 3:1 najbolji sorpcioni kapacitet (2.89 i 3.84 mg/g za As(III) i As(V), respektivno) je dobijen za vreme sinteze od 30 minuta. Od materijala sintetisanih mehano-hemijskom sintezom, smeša Fe2O3:MnO2 u masenom odnosu 3:1 mlevena 30 minuta se pokazala kao najbolja za uklanjanje arsena iz voda. Kinetika sorpcije na ovom sorbentu je brza, dobro je opisana pseudo-drugim redom reakcije sa doprinosom površinske difuzije i intračestične difuzije redu sorpcije. Prisustvo hlorida i sulfata ne utiče na kapacitet sorpcije materijala dok fosfati smanjuju sorpciju arsena za manje od 20 % pri koncentraciji fosfata od 10 mmol/L. Arsen sorbovan za ovaj materijal je čvrsto vezan i njegova mobilizacija pod atmosferskim uticajem je malo verovatna, što ga čini materijalom pogodnim za odlaganje na deponiji posle zasićenja. Dopovanjem titan(IV)-oksida cirkonijumom i gvožđem mikrotalasno-hidrotermalnom metodom dobijeni su materijali velike specifične površine i razvijene strukture mezopora i mikropora, koje omogućavaju brzu kinetiku i veliki kapacitet sorpcije. Na optimalnoj pH vrednosti kapaciteti sorpcije za As(III) su slični kod oba modifikata (8.23 mg/g za 10% Zr i 8.61 mg/g za 10% Fe u poređenju sa 5.52 mg/g za TiO2). Za As(V) bolji rezultati su dobiveni sa modifikatom sa gvožđem (13.72 mg/g za 10 % Zr, 17.35 mg/g za 10 % Fe u poređenju sa 7.39 za TiO2). Sa povećanjem pH vrednosti od 3 do 11 efikasnost sorpcije As(V) skoro linearno opada. Sorpcija As(III) blago raste od pH 3 do pH 9 nakon čega je primećen pad sorpcije do pH 11. Ispitivanjem efikasnosti sorbenata dopovanih cirkonijumom ili gvožđem na realnom uzorku vode, koja sadrži devet puta veću koncentraciju arsena od koncentracije preporučene od strane Svetske Zdravstvene Organizacije, uspešno je smanjena koncentracija arsena na vrednost koja je dozvoljena za upotrebu kao vode za piće.Contamination of drinking water with arsenic represents one of the biggest environmental problems today. World Health Organization in 1993. recommended that the amount of arsenic in drinking water should not be higher than 10 μg/L. Sorption is considered as one of the best available techniques for removal of arsenic from water. In the first part of doctoral thesis effect of chemical modification of commercially available sorbents (BIRM, MGS and MTM) was investigated. Chemical modification of BIRM with Ti and Zr increased sorption capacity, modification with Ti increase of sorption capacity of MTM while chemical modification of MGS didn`t affect it`s sorption capability. MTM modified with Ti successfully removed As(III) or As(V) initial concentration 0.2 mg/L, in pH range from 5 - 8 to value below recommended by World Health Organization. In the second part of work mechano-chemical reaction was used for synthesis of sorbents on the basis of MnO2, Fe2O3 and mixture of Fe2O3:MnO2 in weight ratio 3:1. Investigating dependence of sorption capacity from duration of mechano-chemical synthesis was found that, for MnO2 and Fe2O3, with increase of duration of mechano-chemical synthesis, sorption capacity for arsenic increases. For mechano-chemical synthesis of material on the basis of Fe2O3:MnO2 mixture in weight ratio 3:1, the best sorption capacity (2.89 and 3.84 mg/g for As(III) and As(V), respectively) was achieved with the synthesis time of 30 minutes. From materials that were mechano-chemically synthesized, Fe2O3:MnO2 mixture in weight ratio 3:1 milled for 30 minutes proved to be the best for arsenic removal from water. Kinetic of sorption on this sorbent was fast, with good correlation with pseudo-second rate model and contribution of intraparticle diffusion and surface diffusion to the rate of sorption. Presence of chloride and sulphate anions didn`t affect on sorption capacity of materials while presence 10 mmol/L of phosphates decreased arsenic sorption for less than 20 %. Arsenic is strongly sorbed for this material and it`s mobilization under atmospheric conditions is less likely, which makes it suitable for disposal on land fields after saturation. Doping of titan(IV)-oxide with zirconium and iron using microwave-hydrothermal method, materials with high specific surface area and developed mesopore and micropore volume were obtained, what enables fast kinetic of sorption and high sorption capacities. At optimal pH value, capacity of As(III) sorption are similar for both modificates (8.23 mg/g for 10% Zr and 8.61 mg/g for 10 % Fe in comparison with 5.52 mg/g for TiO2). For As(V) better results were achieved with Fe modificate (13.72 mg/g for 10 % Zr, 17.35 mg/g for 10 % Fe in comparison with 7.39 mg/g for TiO2). With increase of pH value from 3 to 11 efficiency of As(V) sorption almost linearly decreases. Sorption of As(III) slowly increase from pH 3 to 9 after which decrease of sorption is observed until pH 11. Investigating efficiency of Zr and Fe doped sorbents on natural water sample, which contains nine times higher concentration of arsenic than value recommended by World Health Organization, arsenic concentration was successfully decreased to value which allows water to be consumed by humans

Inversion polymorphism in populations of Drosophila subobscura from urban and non-urban environments

Populations of Drosophila subobscura from the urban area of Belgrade and from the locality, Deliblato, which is not under strong anthropogenic influence, were studied with the aim to characterize and compare their genetic structure by examining chromosomal inversion polymorphism. Additional analysis and comparison of this type of polymorphism with several other populations from different habitats in the central Balkans, was done. The obtained results indicate higher heterozygosity in the population from Belgrade. Despite being ecologically marginal and under strong and complex influences, this population did not show a decline in the number of inversions and it is not highly differentiated compared to the referent populations.

The effect of lead on the developmental stability of Drosophila subobscura through selection in laboratory conditions

Fluctuating asymmetry (FA), the increased variation of bilateral symmetry in a sample of individuals, can indicate disturbance in developmental stability caused by environmental and/or genomic stress. This developmental instability was analyzed in Drosophila subobscura maintained for seven generations on two different concentrations of lead in laboratory conditions. The FA4 index showed that the genotypes reared on the higher lead concentration were in developmental homeostasis, except for males in the F7 generation, for both wing size parameters. The results show that different degrees of lead pollution cause different responses to selection of the exposed population in laboratory conditions

Thermal mass impact on energy performance of a low, medium and heavy mass building in Belgrade

Heavy mass materials used in building structures and architecture can significantly affect building energy performance and occupant comfort. The purpose of this study was to investigate if thermal mass can improve the internal environment of a building, resulting in lower energy requirements from the mechanical systems. The study was focused on passive building energy performance and compared annual space heating and cooling energy requirements for an office building in Belgrade with several different applications of thermal mass. A three-dimensional building model was generated to represent a typical office building. Building shape, orientation, glazing to wall ratio, envelope insulation thickness, and indoor design conditions were held constant while location and thickness of building mass (concrete) was varied between cases in a series of energy simulations. The results were compared and discussed in terms of the building space heating and cooling energy and demand affected by thermal mass. The simulation results indicated that with addition of thermal mass to the building envelope and structure: 100% of all simulated cases experienced reduced annual space heating energy requirements, 67% of all simulated cases experienced reduced annual space cooling energy requirements, 83% of all simulated cases experienced reduced peak space heating demand and 50% of all simulated cases experienced reduced peak space cooling demand. The study demonstrated that there exists a potential for reducing space heating and cooling energy requirements with heavy mass construction in the analyzed climate region (Belgrade, Serbia)

Sexual selection can reduce mutational load in Drosophila subobscura

According to theoretical predictions sexual selection can reduce mutational load through male mating success. Males of good genetic quality should be more successful in matings, compared to the males of low genetic quality, thus in this way females can prevent deleterious alleles to be transmitted to the next generation. We tested this hypothesis through set up of two experimental groups from same genetic pool, where in one group genetic quality was manipulated by ionizing radiation. Within each group opportunity for choosing mates was imposed: males and females had no choice or had multiple choice. Mutational load was measured through the variability of different fitness components: fecundity and egg-to-adult viability. Our results indicate that sexual selection can reduce mutational load, only for fecundity. Group with the presence of female choice exhibited higher fecundity than group in which sexual selection was experimentally eliminated, but only in 'irradiated' group. There was no overall difference in egg-to-adult viability between different sexual selection regimes in any of the group. It should be considered that sexual selection can cause sexual conflict, and potential opposite effects of sexual selection and sexual conflict on fitness. Genetic structure of populations, in terms of the level of mutational load, is an important factor which can determinate the role of sexual selection.Prema teorijskim očekivanjima seksualna selekcija može smanjivati mutaciona opterećenja u populacijama, preko uspešnosti mužjaka u parenju. Mužjaci koji su boljeg genetičkog kvaliteta bi trebalo da budu uspešniji u parenju od mužjaka lošijeg genetičkog kvaliteta. Na taj način bi ženke mogle da smanje prenošenje štetnih alela u sledeću generaciju. Ova hipoteza je testirana uspostavljanjem dve eksperimentalne grupe od istog genetičkog pula jedinki, pri čemu su u jednoj mutacije indukovane jonizujućim zračenjem. Unutar svake grupe je nametnuta mogućnost izbora u parenju: mužjaci i ženke nisu imali izbor, ili su imali višestruki izbor. Mutaciona opterećenja su merena preko dve komponente adaptivne vrednosti: fekunditeta i preživljavanja od stadijuma jaja do adulta. Dobijeni rezultati ukazuju da seksualna selekcija može imati uticaj na smanjivanje mutacionih opterećenja ali samo za fekunditet. U prisustvu seksualne selekcije su vrednosti fekunditeta bile veće u odnosu na vrednosti koje su dobijene kad je seksualna selekcija eksperimentalno uklonjena, ali samo u okviru 'ozračene' grupe. Razlike u preživljavanju od jaja do adulta između različitih režima seksualne selekcije nisu dobijene ni u jednoj od grupa. Kako seksualna selekcija često uzrokuje i seksualni konflikt, treba uzeti u obzir njihovo potencijalno delovanje u suprotnim pravcima na adaptivnu vrednost. Genetička struktura populacija, koja podrazumeva i veličinu mutacionih opterećenja, može biti važan faktor od koga će i zavisiti delovanje seksualne selekcija na adaptivnu vrednost.Projekat ministarstva br. 17301

PCR amplification of seven single copy nuclear genes from the Belgrade mummy

Here we report a DNA analysis of a human mummy dated approximately 2300 years BC. We extracted the DNA and used it for further PCR amplification of the following genes: c-fms proto-oncogene for CSF-1 receptor gene (CSF1PO); coagulation factor XIII a subunit gene (F13A01); c-fes/fps proto-oncogene (FESFPS); tyrosine hydroxylase gene (TH01); thyroid peroxidase gene (TPOX), von Willebrand factor gene (vWA) and Y chromosome specific sequence. The alleles from Belgrade mummy do not differ from the most frequent alleles of all present human populations. The exception is FESFPS gene. Belgrade mummy is homozygous for this locus which contains alleles with 7 motif repeats while such allele is found in less than 0.38% of living humans.U ovom radu dati su rezultati analiza molekula DNK izolovanih iz uzorka mumije čoveka stare 2300 godina. Genomska DNK je izolovana i korišćena za PCR amplifikaciju sledećih gena: c-fms protoonkogen za CSF-l receptor gen (CSF1PO), gen za a subjedinicu humanog faktora koagulacije XIII (F13A01), c-fes/fps protoonkogen (FESFPS), gen za tirozin hidroksilazu (TH01), gen za tiroidnu peroksidazu (TROH), gen za von Willebrand-ov faktor(vWA) i specifične sekvence za Y hromozom. Aleli beogradske mumije se ne razlikuju od najučestalijih alela sadašanje humane populacije. Izuzetak je FESFPS gen. Beogradska mumija je homozigotna za ovaj lokus i ima alele sa motivom od 7 ponovaka. Učestalost ovog alela u današnjoj humanoj populaciji je manja od 0.38%.nul

Supplementary data for the article: Krstić, G.; Anđelković, B.; Choi, Y. H.; Vajs, V.; Stević, T.; Tešević, V.; Gođevac, D. Metabolic Changes in Euphorbia Palusrtis Latex after Fungal Infection. Phytochemistry 2016, 131, 17–25. https://doi.org/10.1016/j.phytochem.2016.08.005

Supplementary material for: [https://doi.org/10.1016/j.phytochem.2016.08.005]Related to published version: [http://cherry.chem.bg.ac.rs/handle/123456789/2335

Supplementary data for the article: Dimitrijević, T.; Novaković, I.; Radanović, D.; Novaković, S. B.; Rodić, M. V.; Anđelković, K.; Šumar-Ristović, M. Synthesis, Spectral and Structural Characterization and Biological Activity of Cu(II) Complexes with 4-(Diethylamino)Salicylaldehyde and α-Diimines. Journal of Coordination Chemistry 2020, 73 (4), 702–716. https://doi.org/10.1080/00958972.2020.1740212

Supplementary material for: [https://doi.org/10.1080/00958972.2020.1740212]Related to published version: [http://cherry.chem.bg.ac.rs/handle/123456789/4025

Synthesis, characterization and biological activity of Pt(II) complexes with steroidal thiosemicarbazones

In this work, Pt(II) complexes of previously synthesized steroidal thiosemicarbazones were synthesized and characterized. The ligands and their metal complexes were studied by analytical and spectroscopic data (elemental analysis, IR, 1D-NMR and 2D-NMR, HSQC, HMBC, NOESY, COSY), the analysis of which enabled complete 1H and 13C assignments of each compound including E and Z isomers. All the synthesized ligands and complexes were screened for their cytotoxic and antimicrobial activity. The results demonstrate that the new steroidal thiosemicarbazone complexes were significantly less cytotoxic than the corresponding steroidal thiosemicarbazones. In addition, complexes showed lower antimicrobial activity than the standard drugs, similar to the activity of the starting thiosemicarbazones