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Трећа међународна конференција о електронској микроскопији наноструктура ELMINA 2024, 9–13. септембар 2024. Београд, Србија
No full textSerbian Academy of Sciences and Arts and the Faculty of Technology and Metallurgy,
University of Belgrade, warmly welcome you to the Conference on Electron Microscopy of
Nanostructures ELMINA 2024, the 3rd biennial meeting in the great city of Belgrade.
As the capital of Serbia, Belgrade stands as a city rich in history, culture, and scientific
heritage. Nestled at the confluence of the Sava and Danube rivers, it has served as a crossroads
of civilizations for millennia, from the ancient Celts and Romans to the Ottomans and Aus-
tro-Hungarians. Today, Belgrade is a vibrant metropolis that harmoniously blends its storied
past with a dynamic present, making it an ideal setting for our scientific gathering.
As we convene in this remarkable city, we are reminded of Belgrade’s long-standing
tradition of intellectual pursuit and innovation. University of Belgrade has been at the fore-
front of scientific progress, contributing significantly to various fields including physics, med-
icine, and engineering. The spirit of inquiry and discovery that permeates Belgrade’s academic
community mirrors our own commitment to advancing knowledge and fostering collabora-
tion.
Our gathering in Belgrade is not just an opportunity to share research and ideas; it is
also a chance to draw inspiration from the city’s unique environment. The blend of historic
landmarks such as the Belgrade Fortress and the modern architectural marvels like the Ada
Bridge symbolizes the fusion of tradition and innovation that is at the heart of scientific pro-
gress.
Furthermore, the hospitality and warmth of the Serbian people, renowned for their
generosity and conviviality, provide a welcoming atmosphere for fruitful discussions. The city’s
rich cultural tapestry, evident in its music, cuisine, and arts, offers a vibrant backdrop that will
undoubtedly enrich our experience and stimulate creative thinking.
As we embark on this journey of exploration and exchange in Belgrade, let us embrace
the opportunity to not only advance our scientific endeavors but also to immerse ourselves in
the cultural and historical richness of this extraordinary city.
ELMINA2024 conference features platform and poster presentations, and opportuni-
ties to connect with old friends and colleagues and expand your network. It continues to be
the premier small conference for scientists and students who use electron microscopy in their
research and a strictly in-person meeting, as we are convinced that nothing can substitute
this kind of scientific exchange. The program committee has developed a program spanning
advances in instrumentation and technique development, as well as applications in the analyt-
ical, biological, and physical sciences. Building on the success of previous two ELMINA con-
ferences, the program also contains interdisciplinary presentations as well as the introduction
of artificial intelligence in the field of electron microscopy. It will feature outstanding plenary
speakers, graduate and post-doctoral students, and, of course, a range of social events to en-
hance Belgrade experience. As with previous two ELMINA conferences, this year’s gathering
will be the premier place to attend for staying abreast with the latest technologies, hear about
new developments in applications across all areas of electron microscopy and microanalysis,
and most importantly spend time with colleagues.Our gathering takes place in the esteemed Solemn Hall of the Serbian Academy of
Sciences and Arts, a venue that epitomizes the nation’s dedication to intellectual excellence and
the pursuit of scientific and cultural achievements. Welcome to Belgrade, a city where the past
and the future converge, and where the spirit of scientific inquiry thrives. May our time here
be productive, inspiring, and memorable.Uređivanje zbornika međunarodnog skupa M36Cobiss ID: 15126452
Cavitation damage morphology of the centrifugally cast heat-resistant alloy – HP40 Nb
No full textIn this work, the morphology of the cavitation damage to centrifugally cast austenitic stainless alloys of the HP type was investigated. All specimens subjected to cavitation underwent detailed morphological analyses using light microscopy (LM) and scanning electron microscopy (SEM). The phase composition and lattice parameter verification were further analyzed by energy-dispersive x-ray spectroscopy (EDS) and x-ray diffraction spectroscopy (XRD). The mechanical properties of the material were evaluated by using tensile test, impact test, and macro and micro hardness measurements. The initial results indicate that the material microstructure consists of an austenitic matrix, accompanied by a continuous network of primary eutectic carbides. These carbides come in two types: one with a high concentration of Nb (visible as bright particles) and the other rich in Cr (seen as dark particles). The carbides are of the MC type, where M represents Nb, and of the complex M7C3 type, where M stands for Cr, Ni, and Fe. Carbides located within the inter-dendritic boundaries exhibit either lamellar or skeleton-like structures. The cavitation resistance of the centrifugally cast heat-resistant alloy – HP40 Nb, is primarily influenced by the morphology of the carbides and the mechanical characteristics of the austenitic matrix
Wired for stability: evaluating the electrical performance of a solution-processed zinc oxide-modified silver nanowire transparent electrode
No full textSilver nanowires (AgNWs) have gained much attention owing to their optoelectronic and mechanical properties and are therefore potential candidates to tackle intrinsic drawbacks of currently applied transparent electrodes in various (opto)electronic devices. In order for AgNWs to be justifiably considered as viable, it is necessary to address their insufficient stability by coupling them with another constituent into a nanocomposite. For this purpose, ZnO was chosen because of its low cost, solution processability and barrier properties. In this paper, a fully solution processed AgNW/ZnO TE film was investigated in order to understand the effect of ZnO coating on the electrical stability of AgNWs, including the mechanism of degradation during their exposure to high electrical current densities. The nanocomposite transparent electrode was processed with ZnO coatings to determine their effect on its optoelectronic properties and electrical stability, where the ZnO triple coated AgNW demonstrated the best combination of optoelectronic properties and stability at the highest working voltage
Recycled jute nonvowen material modified with PANI/TiO2 nanocomposite for removal of metal ions from water
No full textWater bodies polluted with heavy metal ions pose a big environmental issue. Another global concern is related to huge amounts of textile waste that is usually landfilled or incinerated. Keeping in mind that one of the pillars of circular economy model is recycling, an effort has been made to face both environmental problems by recycling the carpet fringes based on jute fibers and to manufacture nonwoven sorbent (NWS) by needle punch process, which can be utilized for the removal of heavy metal ions from water. In order to enhance the sorption capacity of NWS, it was in situ coated with polyaniline (PANI). PANI is easy to synthesize, environmentally benign and cheap polymer that posses plenty of amino and imino groups capable to form coordinate bonds with metal ions. To overcome the problem of uneven coating of jute fibers with PANI, the synthesis was performed in the presence of TiO2 nanostructures that control the polymerization of aniline. The effect of PANI/TiO2 nanocomposite containing TiO2 nanoparticles (NPs) and TiO2 nanotubes (NTs) on the sorption of Pb2+ and Cu2+ ions was investigated. The sorption behavior of NWS was studied by discussing the influence of contact time, pH, temperature and initial concentration on uptake of metal ions. The morphology of fiber surface was analyzed by FESEM. Surface chemistry was assessed by FTIR and Raman spectroscopy while electrokinetic properties were evaluated by -potential measurements.
FTIR and Raman spectroscopy indicated the formation of emeraldine base form of PANI whereas FESEM proved the formation of even polymer coating all over the jute fibers. The shape of TiO2 nanostructures did not influence the morphology and chemistry of in situ synthesized PANI/TiO2 nanocomposite and sorption behavior, confirming their restricted role in imparting uniform polymer coating. The isoelectric points of modified samples were shifted towards higher pH values.
The pseudo-second order kinetic model fitted well the experimental data. Experimental data best fitted Langmuir isotherm model. Modification of NWS with PANI/TiO2 nanocomposite led to significant increase in uptake of both metal ions, but the sorption capacities of NWS and modified NWSs for Pb2+ ions were considerably larger than for Cu2+ ions. The sorption was not significantly influenced by temperature. The influence of pH was evaluated in the pH range between pH 3.0-5.5. As expected, the largest uptakes for both metal ions were obtained at pH 5.0-5.5. This is attributed to a negative charge on the surface of NWS modified with PANI/TiO2 nanocomposites beyond the isoelectric point, due to deprotonation of amine groups of PANI. Modified NWs could be regenerated in 0.1 M HNO3 solution and reused at least 5 times with only slight drop in sorption efficiency.
This low-cost and biodegradable sorbent could be used for efficient removal of metal ions from water
Modification of recycled jute nonwoven material with PANI/TiO2 nanocomposite for removal of Zn2+ ions from water
No full textPollution of water bodies with heavy metal ions and the generation of enormous quantities of textile waste, which is commonly burned or landfilled, pose serious environmental problems. Taking into account that recycling is one of the principles of the circular economy model, this study aimed to face these environmental issues by producing nonwoven sorbent (NWS) based on recycled carpet fringes made of jute fibers. NWS was in situ coated with polyaniline (PANI) to improve the sorption capability.
To overcome the problem of uneven PANI coating of jute fibers, PANI synthesis was carried out in the presence of TiO2 nanotubes (NTs), which regulate the aniline polymerization process. The influence of PANI/NTs nanocomposite on the sorption of Zn2+ ions was evaluated. The sorption capacity of untreated and PANI/NTs treated NWS was investigated as a function of temperature, pH, and ion concentration. FESEM analysis revealed a uniform PANI/NTs coating on the surface of jute fibers. Raman and FTIR spectroscopy confirmed the presence of an emeraldine base form of PANI in nanocomposites. The modification of NWS with PANI/NTs coating resulted in considerably improved sorption efficiency. These sorbents withstand at least five sorption cycles without significant changes in Zn2+ ions uptake
Synthesis and characterization of LiTiO2 adsorbent
No full textTiO2-based nanomaterials, such as layered titanates, have attracted much attention due to their
potential applications in lithium batteries, photocatalysis, adsorption, and humidity sensors. To
obtain LiTiO2, nanoanatase powder was hydrothermally treated in 3 M LiOH at 120 ºC for
18 h. The sample was characterized by XRPD, TG/DTA, SEM, and UV-VIS analysis.
Nanoanatase showed high reactivity towards Li+ cations by forming the LiTiO2, which was
revealed by XRPD. The stability of the compound was confirmed by TG/DTA. The adsorption
capacity of the obtained LiTiO2 nanopowder towards the harmful industrial dye Ethyl Violet
(EV) was tested and compared with that of the activated carbon (AC), the most commonly used
adsorbent for the wastewater treatment. LiTiO2 showed even thirteen times more intensive
adsorption than the commercial AC by completely removing EV within 5 minutes, which opens
the chance for practical application of LiTiO2 in wastewater treatment
Нов третман за обезбојување на бои со помош на микрореакторски систем и реагенс на фентон
No full textWastewater treatments in the textile industry faces many challenges, particularly due to the residues of used dyes, which are pollutants characterized by high chemical stability. One promising technology for addressing the issue is an advanced oxidation process (AOP), often utilizing Fenton's reagent as
the oxidizing component. This study focuses on the degradation of the anthraquinone dye Acid Violet
109 using Fenton's reagent in a microfluidic reactor. The microreactor system consists of plunger pump
units, a mixer, and a polytetrafluoroethylene (PTFE) tube. The influences of various process parameters
have been analyzed, including the concentration of Fe2+, microreactor characteristics, the Fe2+/H2O2 molar
ratio, and the total flow rate of the reaction mixture. The results show that treatment with Fenton's reagent
is successful, with efficiencies between 82 and 99 %.Прочистувањето на отпадните води во текстилната индустрија се соочува со многу
предизвици, особено поради остатоците од употребените бои, кои претставуваат загадувачи што
се карактеризираат со висока хемиска стабилност. Една ветувачка технологија за решавање на
проблемот е напреден процес на оксидација (AOP), честопати користејќи го реагенсот на Фентон
како оксидациска компонента. Оваа студија се фокусира на разградувањето на антрахинонската
боја Acid Violet 109 со користење на реагенсот на Фентон во микрофлуиден реактор. Системот на
микрореактор се состои од пумпни единици со клип, миксер и цевка од политетрафлуороетилен
(PTFE). Анализирани се влијанијата на различните параметри на процесот, вклучувајќи ја
концентрацијата на Fe2+, карактеристиките на микрореакторот, моларниот однос Fe2+/H2O2 и
вкупната брзина на проток на реакционата смеса. Резултатите покажуваат дека третманот со
реагенсот на Фентон е успешен, со ефикасност помеѓу 82 и 99 %
An integrated approach to the waste management in the automotive industry
No full textIntegrisan pristup podrazumeva izbor adekvatnih i bezbednih načina smanjenja količine, reci
klaže i unapređenja upravljanja otpadom, adekvatan predtretman. Radom postrojenja za livenje i
mašinsku obradu automobilskih delova generiše se opasan (otpadni premazi, emulzije i muljevi) i
neopasan (prašina i pesak) industrijski otpad. Integrisan pristup upravljanja otpadom obuhvatio je
korišćenje aluminosilikata iz neopasnog otpada u tretmanu opasnog organskog otpada uz is
korišćenje organske faze otpada. U skladu sa najbolje dostupnim tehnikama, primenjeni su procesi
stabilizacije i solidifikacije (S/S) otpada sa dodatkom letećeg pepela i bentonita. Efikasnost predlože nih procesa procenjena je na osnovu rezultata ispitivanja finalnih proizvoda tretmana: uljne faze (sadržaj vode, kalorijska moć, koncentracija hloroida, viskozitet) i očvrslih solidifikata (XRD, SEM EDS i TG-DTG analize). Pritisna čvrstoća (0,50 - 0,81 MPa) i hidraulična konduktivnost (2,58·10-7 - 9,42·10-9 m/s) očvrslih solidifikata ukazale su na potencijalno uspešan proces imobilizacije odabranih vrsta industrijskog otpada. Međutim, analiza parametara za odlaganje otpada (EN 12457 test) je ukazala na potrebu kontrolisanog sadržaja migratornih elemenata u aditivima (leteći pepeo) i organske komponente u otpadmom mulju i emulzijama. Na osnovu dobijenih rezultata, određeni su bilansi potrošnje sirovina i aditiva za S/S tretman otpada i dobijanje očvrslih solidifikata za odlag anje, bez negativnih posledica po životnu sredinu.Integrated management implies adequate and safe ways to prevent, recycle, and manage waste.
Processes of casting and machining parts for the automotive industry produce industrial waste, hazardous (coatings, emulsions, and sludges) and non-hazardous (dust and sand). The integrated approach to waste management included the use of non-hazardous alumino-silicate waste materials in
the treatment of hazardous oil waste with utilization of the organic phase. The stabilization and solidification (S/S) of waste with the addition of fly ash and bentonite was applied. The effectiveness of
the proposed techniques was evaluated based on the results of the testing of the final product: the oil phase (water content, calorific value, viscosity) and hardened solidificates (XRD, SEM-EDS, TGDTG analyses). The unconfined compressive strength (0.50-0.81 MPa) and hydraulic conductivity
(2.58·10-7
- 9.42·10-9 m/s) of solidificates indicated a potentially successful process of immobilization
of selected types of industrial waste. However, the results of leaching test (EN 12457 test) indicated
that the content of migratory elements in additives (fly ash) and the content of the organic component
in the sludge and emulsions must be controlled. Based on the results, raw materials and additives
consumption for S/S treatment was defined for the final waste disposal, without negative environmental consequences
Laccasesʼ production by white rot fungi on agro-industrial waste and their application in the degradation of xenobiotics with a phenolic structure
No full textPredmet istraživanja ove doktorske disertacije je analiza mogućnosti iskorišćenja agroindustrijskog lignoceluloznog otpada za proizvodnju lakaza gljivama bele truleži i primena proizvedenih slobodnih i imobilisanih lakaza u uklanjanju ksenobiotika iz grupe azo boja i tetraciklina. Analiziran je potencijal pet sojeva (Bjerkandera adusta TMF1, Fomes fomentarius TMF2, Schizophyllum commune TMF3, Coriolopsis trogii 2SMKN i Ganoderma resinaceum NMKSS) za proizvodnju lakaza i hidrolaza kvalitativnim, semi-kvantitativnim i kvantitativnim metodama. Dva najpotentnija soja, C. trogii 2SMKN (aktivnost lakaze 107,39 IU/g) i G. resinaceum NMKSS (aktivnost lakaze 24,48 IU/g) gajena na otpadnom pivskom ječmu, korišćena su za dalja istraživanja.
Proizvedene lakaze su okarakterisane i korišćene u biorazgradnji ksenobiotika, pri čemu je lakaza C. trogii 2SMKN efikasno obezbojila 98,95% Orange G za 30 minuta, dok je lakaza G. resinaceum NMKSS razgradila 91,32% amracina za 24 sata. Instrumentalne analize (HPLC, LC-MS, GC-MS) i testovi fitotoksičnosti i antimikrobne aktivnosti potvrdili su efikasnost biorazgradnje. Imobilizacija lakaza je vršena adsorpcijom na reciklirani agroindustrijski otpad, pri čemu su optimizovani uslovi imobilizacije i potvrđena ponovna upotreba u više ciklusa. Imobilisane lakaze su pokazale veću efikasnost u biorazgradnji azo boja i tetraciklina u odnosu na komercijalne lakaze, nadmašujući ih do 12 puta.
Naučni doprinos disertacije ogleda se u identifikaciji i karakterizaciji viših gljiva kao potentnih proizvođača enzima na agroindustrijskom otpadu, kao i u demonstraciji cirkularne ekonomije kroz ponovnu upotrebu otpada kao nosača za imobilizaciju. Proizvedene lakaze, slobodne i imobilisane, pokazale su visoku efikasnost u biorazgradnji ksenobiotika, što može doprineti razvoju održivih tehnologija za zaštitu životne sredine.The subject of this doctoral dissertation is the analysis of the potential for using agro-industrial lignocellulosic waste for the production of laccases by white rot fungi and the application of produced free and immobilized laccases in the removal of xenobiotics from the group of azo dyes and tetracyclines. The potential of five isolates (Bjerkandera adusta TMF1, Fomes fomentarius TMF2, Schizophyllum commune TMF3, Coriolopsis trogii 2SMKN, and Ganoderma resinaceum NMKSS) to produce laccases and hydrolases was analyzed using qualitative, semi-quantitative, and quantitative methods. The two most potent isolates, C. trogii 2SMKN (laccase activity 638.7 U/g) and G. resinaceum NMKSS (laccase activity 187.3 U/g), which are grown, were used for further research.
The produced laccases were characterized and used in the biodegradation of xenobiotics, where the laccase from C. trogii 2SMKN efficiently decolorized 98.95% of Orange G in 30 minutes, while the laccase from G. resinaceum NMKSS degraded 91.32% of amracine in 24 hours. Instrumental analyses (HPLC, LC-MS, GC-MS) and tests of phytotoxicity and antimicrobial activity confirmed the efficiency of biodegradation. Laccase immobilization was performed by adsorption onto recycled agro-industrial waste, optimizing the immobilization conditions and confirming reuse in multiple cycles. Immobilized laccases showed greater efficiency in the biodegradation of azo dyes and tetracyclines compared to commercial laccases, outperforming them by up to 12 times.
The scientific contribution of this dissertation is reflected in the identification and characterization of higher fungi as potent enzyme producers on agro-industrial waste, as well as in demonstrating circular economy through the reuse of waste as carriers for immobilization. The produced laccases, both free and immobilized, exhibited high efficiency in the biodegradation of xenobiotics, which can contribute to the development of sustainable technologies for environmental protection
Hydroxyapatite-based dental inserts: microstructure, mechanical properties, bonding efficiency and fracture resistance of molars with occlusal restorations
No full textThis study aimed to (1) comparatively analyze properties of Sr- and Mg-substituted
hydroxyapatite (HAP)-based dental inserts; (2) evaluate insert bonding to restorative
materials, and (3) evaluate the effect of doped HAP inserts on fracture resistance
(FR) of human molars with large occlusal restorations. By ion-doping with Sr or Mg,
3 insert types were obtained and characterized using XRD, SEM, Vickers hardness and
fracture toughness. Shear bond strength (SBS) was determined between acid etched or
unetched inserts and following materials: Maxcem cement (Kerr); Filtek Z250
(3M) bonded with Single Bond Universal (SBU; 3M) or Clearfil Universal (Cf; Kuraray).
Modified Class I cavities were prepared in 16 intact molars and restored using insert
+ composite or composite only (control) (n = 8/group). FR of restored molars was
determined by static load until fracture upon thermal cycling. Fracture toughness was
similar between Sr/Mg-doped inserts (0.94–1.04 MPam 1/2 p = .429). Mg-doped
inserts showed greater hardness (range 4.78–5.15 GPa) than Sr6 inserts (3.74
± 0.31 GPa; p < .05). SBS for SBU and Cf adhesives (range 7.19–15.93 MPa) was higher
than for Maxcem (range 3.07–5.95 MPa) (p < .05). There was no significant difference
in FR between molars restored with insert-containing and control restorations (3.00
± 0.30 kN and 3.22 ± 0.42 kN, respectively; p > .05). HAP-based inserts doped with
Mg/Sr had different composition and mechanical properties. Adhesive bonding to
inserts resulted in greater bond strength than cementation, which may be improved by
insert acid-etching. Ion-doped HAP inserts did not affect FR of restored molars. In conclusion,
HAP-based dental inserts may potentially replace dentin in large cavities, without
affecting fracture resistance of restored teeth.Peer reviewed manuscript: [https://technorep.tmf.bg.ac.rs/handle/123456789/7495