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Supplementary material for the article: Abduarahman, M. A.; Vuksanović, M. M.; Milošević, M.; Egelja, A.; Savić, A.; Veličković, Z. ; Marinković, A. Mn-Fe Layered Double Hydroxide Modified CelluloseBased Membrane for Sustainable Anionic Pollutant Removal. Journal of Polymers and the Environment 2024. https://doi.org/10.1007/s10924-024-03192-x
No full textThis study aimed to investigate the adsorption of As(V), phosphate, and textile dye Acid Green 25 (AG-25) on layered double hydroxides Mn-Fe_LDH and corresponding membranes (wCell/Mn-Fe_LDH). The wCell membrane, derived from waste tobacco boxes, was formed by cross-linking of epoxy and amino modified cellulose fibers with epoxy modified Mn-Fe_LDH and lysine as cross-linker. Structural and morphological analyses were conducted for Mn-Fe_LDH and wCell/Mn-Fe_LDH. The batch system explored pH, contact time, temperature, and initial concentration effects on wCell/Mn-Fe_LDH adsorption efficiency. Adsorption capacities of 82.71, 106.9, and 130.3 mg g−1 were achieved for As(V), phosphate, and AG-25, respectively, indicating effective anionic species removal. Kinetic analysis suggested intraparticle diffusion as the rate-limiting step. Thermodynamic parameters and ionic strength effects indicated a physisorption mechanism for AG-25 and surface complexation for As(V) and phosphate. Biodegradation experiments after five adsorption/desorption cycles revealed the membrane’s decomposition, with phosphate’s strong bonding releasing essential elements valuable for soil fertilization. Effluent wastewater treatment demonstrated low environmental impact through the formation of insoluble As(V) salts and photocatalytic dye degradation.Related to: [https://technorep.tmf.bg.ac.rs/handle/123456789/7322]Supplementary material for: [https://doi.org/10.1007/s10924-024-03192-x
Supplementary material for the article: Ljubić, V.; Perendija, J.; Cvetković, S.; Rogan, J.; Trivunac, K.; Stojanović, M. ; Popović, M. Removal of Ni2+ ions from Contaminated Water by New Exopolysaccharide Extracted from K. oxytoca J7 as Biosorbent. Journal of Polymers and the Environment 2024, 32, 1105–1121. https://doi.org/10.1007/s10924-023-03031-5
No full textNowadays, exopolysaccharides (EPS) produced from bacterial cells are manufactured for their use in different industries in the world, mainly in the food, pharmaceutical, and wastewater industries. The characteristics of EPS, such as being biodegradable, safe, high adsorption capacity, and reusable, make them significant and potential applications in the purification of contaminated water of heavy metals. In this study, the possible application in biosorption Ni2+ ions from contaminated water was assessed using this exopolysaccharide as a biosorbent. The new exopolysaccharide from the bacterial strain K. oxytoca J7 was extracted, isolated, and characterized using SEM, FTIR, XRD, TGA/DTG, and MALDI-TOF MS analysis. Likewise, the cytotoxic activity was performed for EPS from K. oxytoca J7 strain. The aim of this study was to investigate the possible application of non-toxic exopolysaccharide in the purification of contaminated water by removing Ni2+ ions. The results obtained from the biosorption study showed that the Langmuir model is well suited to describe the adsorption process of Ni2+ ions by EPS from K. oxytoca J7, with a maximum adsorption capacity of 269.97 mg g–1. The importance of this study is the possible use of natural nontoxic exopolysaccharide extracted from the pathogen microorganism, K. oxytoca J7, for the removal of Ni2+ ions from the contaminated water.Related to: [https://technorep.tmf.bg.ac.rs/handle/123456789/6609]Supplementary material for: [https://doi.org/10.1007/s10924-023-03031-5
Supplementary material for the article: Simić, Z. V.; Radović, I. R.; Kijevčanin, M. Lj. Measurement and Correlation of Liquid–Liquid Equilibrium Data for Ternary Systems Water + C1–C3 Alcohols + Diethyl Adipate at 298.15 K and Atmospheric Pressure. Journal of Chemical and Engineering Data 2024. https://doi.org/10.1021/acs.jced.3c00708
No full textThis paper investigates the feasibility of using diethyl adipate (DEA), a green organic solvent, as a separation agent for extracting various alcohols from aqueous solutions. In order to achieve this, liquid-liquid equilibria (LLE) experiments were carried out for four ternary systems: {water + methanol + DEA}, {water + ethanol + DEA}, {water + 1-propanol + DEA}, and {water + 2-propanol + DEA} at 298.15 K and atmospheric pressure. LLE experiments involve determination of certain thermodynamic data such as binodal curves and cloud-point data. Binodal curve data were determined by the cloud-point method using the titration technique, while the tie-line data were determined by optimizing the parameters based on the experimental measurements of the refractive index. Additionally, the distribution coefficients and the separation factors were calculated within the immiscibility region. Hand and Othmer-Tobias correlations were used to examine the reliability of the tie-line data. Also, the experimental ternary LLE data were correlated using the UNIversal QUAsiChemical (UNIQUAC) activity coefficient models. The results confirm that that DEA is a suitable choice for extracting methanol, ethanol, 1-propanol, and 2-propanol from water. The potential of DEA as a separation agent followed the sequence methanol < ethanol < 2-propanol < 1-propanol. UNIQUAC model proved to be effective in correlating the LLE data.Related to: [https://technorep.tmf.bg.ac.rs/handle/123456789/7342]Supplementary material for: [https://doi.org/10.1021/acs.jced.3c00708
Gelatin-/Alginate-Based Hydrogel Scaffolds Reinforced with TiO2 Nanoparticles for Simultaneous Release of Allantoin, Caffeic Acid, and Quercetin as Multi-Target Wound Therapy Platform
No full textThis study proposes synthesis and evaluation of gelatin-/alginate-based hydrogel scaffolds reinforced with titanium dioxide (TiO2) nanoparticles which, through their combination with allantoin, quercetin, and caffeic acid, provide multi-target therapy directed on all phases of the wound healing process. These scaffolds provide the simultaneous release of bioactive agents and concurrently support cell/tissue repair through the replicated structure of a native extracellular matrix. The hydrogel scaffolds were synthesized via a crosslinking reaction using EDC as a crosslinker for gelatin. Synthesized hydrogel scaffolds and the effect of TiO2 on their properties were characterized by structural, mechanical, morphological, and swelling properties, and the porosity, wettability, adhesion to skin tissue, and simultaneous release features. The biocompatibility of the scaffolds was tested in vitro on fibroblasts (MRC5 cells) and in vivo (Caenorhabditis elegans) in a survival probe. The scaffolds revealed porous interconnected morphology, porosity of 88.33 to 96.76%, elastic modulus of 1.53 to 4.29 MPa, full hydrophilicity, favorable skin adhesivity, and biocompatibility. The simultaneous release was investigated in vitro indicating dependence on the scaffold’s composition and type of bioactive agents. The novel scaffolds designed as multi-target therapy have significant promise for improved wound healing in a beneficial and non-invasive manner
Catalytic hydrogenation reaction micro-kinetic model for dibenzyltoluene as liquid organic hydrogen carrier
No full textThe implementation of the liquid organic hydrogen carrier (LOHC) technology for efficient energy storage requires the development of a reliable kinetic model for both hydrogenation and dehydrogenation processes. In this research study, the catalytic hydrocarbon saturation for a dibenzyltoluene (DBT) mixture solution, containing dibenzylbenzene (DBB), dibenzylethylbenzene (DBEB) and impurities has been performed in the presence of Ru/Al2O3 particles. The influence of different reaction conditions, such as temperature, pressure, initial reactant concentration, catalyst amount and stirring speed has been examined. A measurement-based system micro-kinetics, based on the Langmuir–Hinshelwood mechanism with dissociative H2 surface adsorption, has been derived. H2 thermodynamic solubility equilibrium was defined through Henry's law. The adsorbing, desorption and reactivity of inert solvent molecules was not considered to be relevant. The mass transfer resistance over 1000 rpm stirring speed was negligible. Relative- and mean squared error of representation were 40.9% and 1.00×10−4, respectively. Expressions gave an excellent data prediction for the profile period trends with a relatively accurate estimation of H2 intermediates' rate selectivity, H2-covered area approximation and pathway rate-determining steps. Due to the lack of commercially available standard chemical compounds for quantitative analysis techniques, a novel experiment-based numerical calibration method was developed. Mean field (micro)kinetics represent an advancement in the mesoscale mechanistic understanding of physical interface phenomena. This also enables catalysis structure–activity relationships, unlocking the methodology for new LOHC reaching beyond traditional, such as ammonia, methanol and formate, which do not release H2 alone. Integrated multiscale simulations could include fluidics later on
Study on thermal stability of water-based polyurethanes derived from hydroxypropyl terminated poly(dimethylsiloxane)
No full textIn this paper, thermal and thermo-oxidative stability of three water-based polyurethanes (PUs) derived from hydroxypropyl terminated poly(dimethylsiloxane) (HPT-PDMS) were studied. The structural properties of the synthesized samples were investigated by 1H NMR measurements, while characterization of their surface, performed by atomic force microscopy, revealed the existence of microphase-separated structures. According to the results obtained by thermogravimetric analysis (TGA), thermo-oxidative and thermal stability of the investigated water-based PUs decreases with decreasing HPT-PDMS content. Furthermore, obtained results also suggest that both, thermo-oxidative and thermal degradation reaction of water-based PUs occurred as a three-step process. In both atmospheres the first step of degradation is attributed to the degradation of weak urethane and urea bonds and the second step to the decomposition of polysiloxane chains. In order to undertake a detail investigation of thermal degradation process of water-based PUs, TG measurements in nitrogen atmosphere at four different heating rates (5, 10, 15 and 20 °C/min) were performed. Different iso-conversional model-free methods, such as Ozawa-Flynn-Wall, Kissinger-Akahira-Sunose and Friedman, were applied to determine apparent activation energy of thermal degradation reaction (Ea) of water-based PUs, at different conversions (α). Deviation in parallelism of the obtained fitted lines confirmed that thermal degradation reaction of water-based PUs occurred in three successive steps, followed by different degradation mechanism. Since linear fitting of the experimental data by Friedman method had the lowest correlation coefficient, Ozawa-Flynn-Wall and Kissinger-Akahira-Sunose methods were considered to be the most reliable for Ea calculation. A comprehensive analysis of the obtained results revealed that, despite their similar structure, each water-based PU shows unique profile of Ea = f(α) plot
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). 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.This is the peer reviewed version of the following article: Matić, T., Ležaja Zebić, M., Miletić, V., Trajković, I., Milošević, M., Racić, A.,& Veljović, Đ.. (2024). Hydroxyapatite-based dental inserts: microstructure, mechanical properties, bonding efficiency and fracture resistance of molars with occlusal restorations. in Journal of Biomedical Materials Research Part B: Applied Biomaterials. John Wiley and Sons Inc., 112(1), e35331., which has been published in final form at [https://doi.org/10.1002/jbm.b.35331]. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Use of Self-Archived Versions. This article may not be enhanced, enriched or otherwise transformed into a derivative work, without express permission from Wiley or by statutory rights under applicable legislation. Copyright notices must not be removed, obscured or modified. The article must be linked to Wiley’s version of record on Wiley Online Library and any embedding, framing or otherwise making available the article or pages thereof by third parties from platforms, services and websites other than Wiley Online Library must be prohibited
Assessment of groundwater suitability for drinking and irrigation in the Jadar river valley
No full textPodzemne vode su ključan izvor slatke vode neophodan za regionalni razvoj i očuvanje
ekologije, što čini bezbednost njihovog korišćenja od presudnog značaja za dobrobit ljudi.
U ovom radu je ispitivana pogodnost podzemnih voda za piće i navodnjavanje u dolini
reke Jadar. Pogodnost podzemnih voda za piće procenjivana je korišćenjem entropijskog
indeksa kvaliteta vode (EWQI), dok je pogodnost podzemnih voda za navodnjavanje
procenjena korišćenjem koeficijenta adsorpcije natrijuma (SAR) i procenta natrijuma
(%Na). Rezultati su pokazali da je 13,6% uzoraka imalo EWQI vrednost nižu od 100, što
su podzemne vode pogodne za piće. Proračunate SAR i %Na vrednosti kretale su se u
rasponu 0,2–744 i 4%–99,5%, pri čemu je većina uzoraka pripala kategorijama odličnog
do dobrog kvaliteta vode. Voda najlošijeg kvaliteta primećena je u centralnom delu
istraživanja područja, dok se kretajući ka obodu njen kvalitet poboljšavao.Groundwater is a vital freshwater resource crucial for regional development and ecological
preservation, making its safety imperative for human well-being. This study investigated
the suitability of groundwater for drinking and irrigation purposes in the Jadar River
valley. The suitability of groundwater for drinking was assessed using the entropyweighted water quality index (EWQI), while the suitability of groundwater for irrigation
was evaluated using the sodium adsorption ratio (SAR) and sodium percentage (%Na)
indices. The results showed that 13.6% of the samples exhibited an EWQI value below
100, suggesting groundwater suitable for drinking. The SAR and %Na of the samples
ranged from 0.2 to 744 and 4% to 99.5%, respectively, with the majority of the samples
falling within the excellent to good water quality categories. The central portion of the
study area exhibited the poorest water quality, which gradually improved towards the
periphery
Activated charcoal as a carrier of probiotics: A new approach for pathogen elimination in wounds
Get PDFAntibiotic resistance isone of the biggest threats to global health, food securityand development today[1].However, development of conventional anti-infective drugs is going slowly, so new innovative strategies and more research are urgently needed in identifying, developing, implementing and evaluating novel therapies for antibiotic-resistant infections.The two-year ProHealingAC project, funded by the Science Fundof theRepublicof Serbia, aims to use beneficial properties of ACand probiotic microorganisms in developing anew strategy for prevention and localtreatment of antibiotic-resistant infections in wounds. Previously, it has been shown that activated charcoal (AC) in conjunction with different active agents has an efficient antimicrobial activity [2,3]. The aimof this projectis to develop biocomposites (BCs) based on AC fabric, as adsorptive component, and probiotics, as bioactive component in order to achieve their synergetic activity forefficient and sustained localdelivery of bioactive agents directly into the woundarea.Also, special attention has been given to the influence of glucose level (normo-and hyperglycemia) in the microenvironment of the wound.ExcellMater Conference 2024: Innovative Biomaterials for Novel Medical Devices, Belgrade, Serbia, April 10-12, 202
Production technology and characterization of alginate-based impregnated gauze
Get PDFTraditional cotton wound dressings, like gauze and bandages, remain popular in wound care due to their affordability. However, they have drawbacks: adhering to wounds, risking tissue damage and low absorbance of secretions, requiring multiple layers, and causing discomfort. Modern alternatives, such as alginate hydrogel dressings, target these issues. Designed for moderate to intense exudate wounds, they enhance comfort and treatment effectiveness. Yet, their higher cost limits accessibility. Moreover, neither alginate nor cotton gauze offer bioactivity, while mechanical strength of alginate hydrogel may be inadequate. This work aims to develop enhanced gauzes to overcome these challenges, offering improved functionality at affordable costs and superior wound care.ExcellMater Conference 2024: Innovative Biomaterials for Novel Medical Devices, Belgrade, Serbia, April 10-12, 202