Primena laserskih tehnika za određivanje optičkih parametara materijala

The influence of stimulated electromagnetic radiation in optical part of spectra (visible, UV and IR) to materials is for almost half a century the issue of research including a lot of unexplained processes and stances. From one point of view represents new form of source and from the other the relation to spontaneous sources in the same spectral area as well as the power. The issues could be divided into theoretical-experimental processes from biomodulation to destruction and to the area where coherent radiation is used in diagnostic methods for material study. In this thesis the subject was approached from theoretical-experimental side. The observation of materials was forwarded trough material response functions, meaning trough their collective role expressed using optical characteristic materials. In experimental part of the thesis a series of experiments was conducted, determining certain optical parameters for chosen samples along with spectroscopic approach. That would be the first approach for following series of experiments in which plant samples namely seeds (wheat, corn, spinach, basil, thyme) where axposed to various types of laser beams (He-Ne, Nd3+:YAG, semiconductor) on basic transitions and according to laser possibilities at higher harmonics. The results of sample irradiation with given parameters, were monitored until the end of vegetation periods. The morphological characteristic of irradiated and nonirradiated samples were monitored as well as quantitative indicators of induced modifications. In given area of energy densities and exposition doses, almost all samples shown positive influence of coherent radiation. For some of the samples a change in FT-IR spectra was observed. For use of lasers in main processes, occurring in metrology where linear and nonlinear characteristics of materials occurs, scattering, absorption and fluorescence of materials including materials of the live world (tissue, cells and their parts). These processes are observed and used for optical defining of objects, and from their values (characteristic) and from wavelength of the used light depends which effect will overcame including resonance. In the area of techniques based on static and dynamic scattering angular distributions play a considerable role in determination of objects by size and shape. So in this thesis, using chosen software, a number of angular distribution simulations was done for microorganisms, typical particles and water. Given approach could using data bases or newly measured values, without modifications, be used for other adequate samples, simplifying the experiments in advance including characteristic maxima at certain angles for chosen samples. Ecological side of laser application viewed through accidental (fire) processes contains multitude of approaches from use of lidars to sensory role of much simpler systems. In this thesis the approaches to monitoring of certain area (ground, earth, different covers, water areas, atmosphere phenomena) are perceived trough analysis of possible remote devices lidar based. It’s a principal including fire processes here analyzed, searching for possibilities of software support, covering certain experimental settings. The nature of combustion products could be also viewed by simulation of scattering processes (propane and acetylene sooth)

Synthesis and characterization of materials obtained by modification of natural zeolite (clinoptilolite) and phosphate based microporous materials with zeolitic structure

U prvom delu disertacije ispitana je mogućnost modifikacije zeolitskog tufa iz rudnika Zlatokop (okolina Vranjske Banje) u cilju dobijanja novih adsorbenata, dok je u drugom delu opisana mogućnost sintetisanja novih mikroporoznih jedinjenja sa strukturnim svojstvima zeolita, na bazi fosfata. Zeolitski tuf modifikovan benzalkonijum‐hloridom (BC) ispitan je kao adsorbent salicilata (SA). SA‐obogaćeni zeolit je dalje ispitan kao model sistem za kontrolisano otpuštanje farmakološki aktivne supstance i kao dezinficijens u odnosu na bakterije: Gram‐negativnu Escherichia coli i Gram‐pozitivnu Staphylococcus aureus. Utvrđeno je da oko 80% salicilata pređe u rastvor sa adsorbenta tokom 5 sati. Kinetika desorpcije prati Korsmajer‐Pepasov kinetički model koji najčešće opisuje kinetiku otpuštanja farmakološki aktivnih supstanci sa različitih podloga. Zeolitski tuf modifikovan hidratisanim gvožđe(III)‐oksidom ispitan je kao adsorbent selenit‐ i selenat‐jona. Ovaj adsorbent vezuje ispitivane anjone tako što na površini adsorbenta dolazi do obrazovanja oksokompleksa i Se‐O‐Fe i Se‐O‐Si veza. Ovaj adsorbent ispitan je i kao supstrat u uzgoju medicinski značajne gljive Pleurotus ostreatus (bukovače). Gljive uzgajane na ovom supstratu usvajaju selen sa površine adsorbenta i prevode ga u selenoproteine. U drugom delu teze ispitana je strukturna uloga 3‐metilaminopropilamina (MPA) u sintezi poroznih neorganskih polimera na bazi fosfata. Praćen je uticaj temperature i vremena, molskog odnosa reaktanata i prisustva fluorid‐jona na kristalizaciju alumofosfata, metal‐supstituisanih alumofosfata i cinkfosfata. Dobijeni su različiti kristalni proizvodi od kojih su neki izostrukturni sa već poznatim alumo‐ i galofosfatima, a neki su novi kristalni proizvodi.In the first part of the dissertation, the possibility of modifying the zeolitic tuff from the mine Zlatokop (near Vranjska Banja) was investigated in order to obtain new adsorbents. The second part presents the possibility of synthesize of new phosphate‐based microporous materials with structural properties of zeolites. The zeolitic tuff modified with benzalkonium chloride (BC) was tested as an adsorbent for the salicylate‐anions (SA). SA‐enriched zeolite was further studied as a model system for the controlled release of the pharmacologically active substance as well as a disinfectant toward the pathogenic bacteria: Gram‐negative Escherichia coli and Gram‐positive Staphylococcus aureus. It was found that about 80% of the adsorbed salicylate is delivered into solution during 5 hours. The release profile of SA from BC‐modified zeolite into solution is in a good agreement with the Korsmeyer‐Peppas kinetic model, which is usually used for description of the release kinetics of the pharmacologically active substances from different substrates. The zeolitic tuff modified with hydrated iron(III) oxide was investigated as an adsorbent for selenite and selenate ions. The adsorbent binds the anions through formation of Se‐O‐Fe and Se‐O‐Si bonds and oxo‐complexes. The spent adsorbent was tested as a supplement for the cultivation of mushroom Pleurotus ostreatus. The mushrooms grown on the substrate show possibility to adopt selenium from the surface and transfer it into selenoproteins. Structural role of 3‐methylaminopropylamine (MPA) in the synthesis of the porous inorganic phosphate‐based polymers was tested in the second part of thesis. The influence of temperature and time, the mole ratio of reactants and the presence of fluoride ions on the crystallization of aluminophosphates, metalsubstituted aluminophosphates and zincophosphates was investigated. Some of the obtained crystalline products are isostructural with the known alumo‐ and galophosphates, while others are new crystalline products

Lidarske metode u ranom otkrivanju i praćenju požarnih procesa i njihovoj simulaciji

Methods for eearly detection, dynamics monitoring and surveillance of fire processes are topics which belong to the method class where high reliability, detection rate and response imply. Although various transformation processes exist for measuring and quantification of the principal parameters of fire processes, the use of optical methods (including ultraviolet, visible and infrared ranges) is increasing. Laser - quantum generator in all three parts of optical range through various measurement methods of real atmospheric parameters or fire environment are for a long time included in this area. Operation methods are related to linear and nonlinear processes enabling different ranges of measurement uncertainty. This paper is on one hand, dedicated to the analysis of up-to-date optical methods based on lidar solutions and on the other to simulation methods and possibilities of modern software tools.Metode za rano otkrivanje, praćenje dinamike i nadgledanje požarnih procesa su problematika, koja pripada klasi metoda, gde se podrazumeva visoka pouzdanost, brzina detekcije i odziva. Iako postoje različiti procesi transformacije glavnih parametara požarnih procesa u cilju merenja i kvantifikacije, ipak su optičke metode (uključujući ultraljubičasti, vidljivi i infracrveni opseg) sve više u upotrebi. Laseri - kvantni generatori, u sva tri dela optičkog područja, kroz različite metode merenja parametara atmosfere ili požarne okoline, su odavno uključeni u problematiku. Metode rada su vezane za linearne i nelinearne procese, koji omogućuju različite opsege mernih nesigurnosti. Rad je posvećen, sa jedne strane, analizi savremenih optičkih metoda baziranih na lidarskim rešenjima, a sa druge, metodama simulacije i mogućnostima savremenih softverskih alata

Optimization of ultrasound-assisted extraction of total polyphenolic compounds from Juglans nigra L. leaves

The ultrasound-assisted extraction of Juglans nigra L. leaves was optimized with respect to total phenolic content (TP) of the extracts by varying the concentration of aqueous ethanol solution (E) and different solvent-to-solid ratio (S). The influence and optimum of the operating parameters (E and S) was examined using response surface methodology (RSM). The statistical criteria indicated the adequacy, reliability and precision of the developed RSM model. RSM showed that maximum extraction yield of TP 28.59 mg g(-1) of draw plant was achieved at the optimal values of 50% E and 20 kg kg(-1) S. Using the modelled optimized conditions, the detected relative difference between the predicted and the experimental yield was +/- 2.3 %. The determined TP content in the extracts varied from 12.54 to 29.26 mg GAE g(-1) of dry plant indicated that J. nigra is a valuable source of phenolic substances. The extracts of J. nigra leaves obtained under optimal conditions showed good antioxidant activity (IC50 = = 18.91 +/- 0.03 mu g cm(-3)) which was determined by the scavenging effect on 2,2-diphenyl-1-picrylhydrazyl radical. The optimization of the TP extraction process is the important step in improving techno-economics of the potential commercial preparation of J. nigra extracts, as natural source of antioxidants

The applicability of species- and trichothecene-specific primers in monitoring the Fusarium graminearum species complex and its impact on the surveillance of fusarium head blight in winter wheat in Serbia

Monitoring changes in the prevalence of Fusarium species and toxin production is an important tool for the integrated control of Fusarium head blight (FHB). However, methods for the high-throughput screening of Fusarium populations have been developed using isolates with limited geographic origins. In this study, we used species- and trichothecene-specific primers to monitor the F. graminearum species complex (FGSC) originating from Serbia. We also tested the applicability of the primers to the surveillance of FHB. We analyzed two hundred and ten isolates collected from thirty two locations and five winter wheat varieties over a three-year period. Using multiple correspondence analysis (MCA), we investigated associations between Fusarium-damaged kernels (FDK) and location, variety, members of the FGSC, and their predisposition for mycotoxin production. The results revealed that the species-specific primers were not specific for 11% of the F. graminearum population. The primer sets were 98.5%, 95.2%, and 92.4% effective in the multilocus genotyping of Tri7, Tri3, and Tri5 genes, respectively. We found that individual wheat varieties were associated with isolates that could not be characterized using species- and trichothecene-specific primers. Alternaria spp. had a significant influence (p < 0.001) on grain infection with F. graminearum, indicating the necessity to further investigate its impact on the pathogenesis of the F. graminearum clade

Removal of arsenic(III) oxyanions from wastewater using aminosilane -modified natural and synthetic zeolite

Silanization of the natural and synthetic zeolites as well as their use as adsorbents for removing arsenic(III) oxyanions from wastewater are the topic of this paper. Two types of zeolite were used: natural zeolite-clinoptilolite from Zlatokop deposit, Vranjska Banja, Serbia, previously converted to H+-form and synthetic zeolite, mordenite. The modification was performed with solution (3-aminopropyl) triethoxysilane (APTES). The presence of APTES on the surface of zeolite was confirmed using TG/DSC and FTIR analysis. The results showed that natural aminosilane-modified zeolite has a higher adsorption capacity for arsenic(III) oxyanions compared to mordenite prepared in the same way. The kinetic data follow the Lagergren pseudo-second-order model. This model implies a chemical interaction between AsO33–- ions and functional groups on the silanized zeolite surface.9th Croatian-Slovenian-Serbian Symposium on Zeolites, 23rd-25th September 2021, Split, Croati

Adsorpcija korisnih metala iz kondenzata dobijenog vakuum pirolizom baterija na alumosilikatnim mineralima

Baterije su jedan od najčešće korišćenih izvora energije. Međutim, nakon upotrebe, one predstavljaju ekološki problem. Kao rešenje, nameće se reciklaža kojom iskorišćene baterije postaju sekundarni izvori korisnih metala što njihovu proizvodnju čini ekonomski značajno isplativijom. Da bi se postupak reciklaže prilagodio očuvanju životne sredine neophodno je pronalaženje ekološki prihvatljivih i efikasnih postupaka. Kao moguće rešenje nameće se postupak kojim bi se, nakon vakuum pirolize baterija, korisni metali vezali na odgovarajući adsorbent te ponovo iskoristili. Kao adsorbenti ispitani su alumosilikatni minerali: lako dostupan i ekonomski isplativ prirodni zeolit ležišta Zlatokop, Vranjska Banja, i sintetički zeolit A, dobijen laboratorijskom sintezom iz otpadnog letećeg pepela deponije termoelektrane Morava, Svilajnac. Rendgenskom difrakcijom praha potvrđeno je da sintetisani uzorak pripada strukturnom tipu LTA, odnosno zeolitu A, kao i da u zeolitnom tufu dominira klinoptilolit, najzastupljeniji prirodni zeolit. Ispitivanjem termičkih svojstava pokazno je da su oba zeolita stabilna do 800 °C. Efikasnost adsorpcije ispitana je iz višekomponetnog kondenzata u kome su bili prisutni joni Cd(II), Pb(II) i Hg(II). Dobijeni rezultati pokazali su da prirodni zeolit ima najveći afinitet prema kadmijumu (98%), zatim prema olovu (65%) i živi (45%). Jedino u slučaju žive brzina mešanja pozitivno utiče na stepen adsorpcije. Zeolit A pokazao je maksimalnu efikasnost (100%) u odnosu na olovo(II) i kadmijum(II), dok živu(II) nije vezao što bi se moglo pripisati kompeticiji prisutnih jona u rastvoru, manjoj specifičnoj površini, kao i manjem kapacitetu katjonske izmene u poređenju sa prirodnim zeolitom. Podaci dobijeni ispitivanjem kinetike adsorpcije pokazali su da se maksimalna efikasnost ostvaruje za vrlo kratko vreme korišćenjem kako prirodnog, tako i zeolita dobijenog iz otapadnih sirovina čime je moguće valorizovati korisne metale iz istrošenih baterija i na taj način produžiti njihov vek trajanja.Book of Abstract

Analitički i numerički aparati za primene lasera u dijagnostičke svrhe u linearnoj i nelinearnoj oblasti

Primena lasera sa procesima rasejanja i interakcije zahteva rešavanje teorijskih problema, koji se razvojem računarskih alata svode na brze provere. Zadaci u vezi metroloških problematika pokrivaju zadatake sa angularnom raspodelom, monohromatskih i polihromatskih problema matrice rasejanja, specijalne funkcije ili komponentni prilaz definisanim geometrijama i koherentnih osobina snopa, rasejavača i ugla posmattranja. Laserski snopovi velikog intenziteta izazivaju niz efekata u atmosferi ili u prolazu kroz materijal, uključujući i disturbanse u rezonatorima zbog uticaja elastičnih i neelastičnih rasejanja i promene koeficijenata refleksije elemenata (ogledala), koji su u radnom prostoru kvantnog generatora-pojačavača. Rad se bavi izabranom problematikom teorijsko-analitičko-numeričke prirode i pored pozivanja na zadatke iz prakse, analizira podrške informacione tehnologije

Analitički i numerički aparati za primene lasera u dijagnostičke svrhe u linearnoj i nelinearnoj oblasti

Primena lasera sa procesima rasejanja i interakcije zahteva rešavanje teorijskih problema, koji se razvojem računarskih alata svode na brze provere. Zadaci u vezi metroloških problematika pokrivaju zadatake sa angularnom raspodelom, monohromatskih i polihromatskih problema matrice rasejanja, specijalne funkcije ili komponentni prilaz definisanim geometrijama i koherentnih osobina snopa, rasejavača i ugla posmattranja. Laserski snopovi velikog intenziteta izazivaju niz efekata u atmosferi ili u prolazu kroz materijal, uključujući i disturbanse u rezonatorima zbog uticaja elastičnih i neelastičnih rasejanja i promene koeficijenata refleksije elemenata (ogledala), koji su u radnom prostoru kvantnog generatora-pojačavača. Rad se bavi izabranom problematikom teorijsko-analitičko-numeričke prirode i pored pozivanja na zadatke iz prakse, analizira podrške informacione tehnologije

Theoretical support of modern issues related to laser techniques, applications of coherent radiation and modern technologies

Modern problems of the Earth’s population are increasing in the areas related to the basic concepts of survival of living beings, but also with opposite views, if parallels are made between energy and ecology. Many new technologies are searching for their way towards development and must be viewed from several points of view. Inthis paper, the issue is addressed through modern laser techniques in terms of obtaining energy for various purposes concerning selected roles in medicine, as well as the impact on flora, fauna and as a support to other technologies both classical and modern. Contemporary attributes of lasers and other quantum generators in termsof coherence, power and intensity densities have significantly increased, although some predictions from the time of the first quantum generator masers, like gammarasers (and X raser) are still relatively far from commercial concepts. Some of the possible contemporary implementations of quantum generators in measurements control and processing schemes, along with other possible applications of various laser types, have been estimated. The paper focuses on the characterization of today’s problems with Covid-19 virus, only from the engineering point of view. The lexical side of the issue is also included, as well as the social management needswith the application of modern technologies, including help from natural sciences