Supplementary material for the article: Šoštarić, T. D.; Petrović, M. S.; Pastor, F. T.; Lončarević, D. R.; Petrović, J. T.; Milojković, J. V.; Stojanović, M. D. Study of Heavy Metals Biosorption on Native and Alkali-Treated Apricot Shells and Its Application in Wastewater Treatment. Journal of Molecular Liquids 2018, 259, 340–349. https://doi.org/10.1016/j.molliq.2018.03.055

Supplementary material for: [https://doi.org/10.1016/j.molliq.2018.03.055]Related to published version: [http://cherry.chem.bg.ac.rs/handle/123456789/2152]Related to accepted version: [http://cherry.chem.bg.ac.rs/handle/123456789/2970

Particle-to-particle heterogeneous nature of Coals A case of large coal particles

In the present paper, the results of investigation of the heterogeneous nature of coals are given. Microscopic observations of coals of different rank and mineral matter content were performed. The content of minerals and macerals and the size of their grains were determined in the coal samples. Two samples of lignite rich in minerals were analyzed in detail by measuring the ash content for each particle and batches containing numerous [100] coal particles. The additional analyses were performed with the particles before and after sink-float separation. The obtained results showed an increase of heterogeneity with mineral matter content. The statistical analysis showed that many particles should be used for an experiment for obtaining reliable data with a desired level of certainty. In the case of batch experiments with 5 g Kolubara B coal (about 100 particles, size 4.76-7.0 mm), the experiment should be repeated at least 7, 19, and 100 times in order to obtain a mean value in the confidence intervals 5.0%, 2.5%, and 1.0%, respectively, for a 95% probability (if sample heterogeneity is the only cause for variations in results). However, regardless of increase of reproducibility and repeatability of obtained results, a large amount of samples and numerous repetitions of experiments cannot exclude differences in experimental results between homogenous and heterogeneous samples

Synthesis, Characterization, and Antimicrobial Activity of Silver Nanoparticles on Poly(GMA-co-EGDMA) Polymer Support

Poly(glycidyl methacrylate-co-ethylene glycol dimethacrylate) (poly(GMA-co-EGDMA) macroporous copolymer decorated with silver nanoparticles was prepared by a modification of poly(GMA-co-EGDMA) in the reaction with arginine, and consequent reduction of silver ions with amino groups. The mercury intrusion porosimetry, transmission electron microscopy, X-ray diffraction, UV-vis reflection spectroscopy, and inductively coupled plasma atomic emission measurements were used to characterize obtained composite. The coordination of silver nanoparticles to the poly(GMA-co-EGDMA) copolymer was studied using infrared spectroscopy. Time dependence and concentration dependence of the antimicrobial efficiency of composite were tested against Gram-negative bacteria Escherichia coli, Gram-positive bacteria Staphylococcus aureus, and fungus Candida albicans. The composite ensured maximum reduction of both bacteria, while the fungi reduction reached satisfactory 96.8%. Preliminary antimicrobial efficiency measurements using laboratory flow setup indicated potential applicability of composite for wastewater treatment

Charge-transfer complex formation between TiO2 nanoparticles and thiosalicylic acid: A comprehensive experimental and DFT study

Under normal conditions, titanium dioxide does not absorb visible light photons due to large band gap. Nevertheless, when titanium dioxide nanoparticles (TiO2 NPs) are surface-modified with thiosalicylic acid (TSA), their optical properties are altered owing to the formation of charge transfer complex that initiates absorption in the visible spectral range. Colloidal and sol-gel techniques were used to synthesize uniform TiO2 NPs of different sizes (average diameters in the range 4-15 nm), and effects of their subsequent modification by TSA molecules were compared with effect of modification of commercial Degussa TiO2 powder. Thorough microstructural characterization of TiO2 nanoparticulates was performed including transmission electron microscopy (TEM) and X-ray diffraction (XRD) analysis, as well as nitrogen adsorption-desorption isotherms. Optical measurements revealed that all surface-modified TiO2 samples with TSA have similar spectral features independent of their morphological differences, and, more importantly, absorption onset of modified TiO2 samples was found to be red-shifted by 1.0 eV compared to the unmodified ones. The mode of binding between TSA and surface Ti atoms was analyzed by infrared spectroscopy. Finally, the quantum chemical calculations, based on density functional theory, were performed to support optical characterization of surface-modified TiO2 with TSA. (C) 2017 Elsevier B.V. All rights reserved

Electronic structure of surface complexes between CeO2 and benzene derivatives: A comparative experimental and DFT study

Surface modification of CeO2 nano-powder, synthesized by a self-propagating room temperature method with salicylate-type ligands (salicylic acid and 5-aminosalicylic acid) as well as catecholate-type ligands (catechol, 3,4-dihydroxybenzoic acid, caffeic acid and 2,3-dihydroxy naphthalene), induces the appearance of absorption in the visible spectral region due to the interfacial charge transfer (ICT) complex formation. Thorough characterization involving transmission electron microscopy, XRD analysis, and nitrogen adsorption-desorption isotherms, revealed that loosely agglomerated CeO2 particles of the size ranging from 2 to 4 nm have cubic fluorite structure and specific surface area of 140 m2/g. The attachment of salicylate- and catecholate-type of ligands to the surface of CeO2 powders leads to the formation of colored powders with tunable absorption in the visible spectral region. The density functional theory calculations with properly design model systems were performed to estimate the alignment of energy levels of various inorganic/organic hybrids. A reasonably good agreement between calculated values and experimental data was found. © 201