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Introduction: Hemangiopericytoma is a rare tumor arised from the pericytes, contractile spindle cells that surround the capillaries and post-capillary venules. The tumor was found equally among males and females. Case report: We report a case of a 63-year-old female who presented a giant painful mass on her right shoulder that occurred one year before admission. Limited range of motion and a sense of tingling along the affected arm was present also. An irregular, oval-shaped mass, colored dark-red, with signs of necrosis was the maximal diameter of 14cm. Routine laboratory analyzes showed results within the range of referenced values. Lung X-ray and ultrasonographic examination of the abdomen showed no signs of secondary tumor deposits, and no osteo-muscular lesions in the affected region. Ultrasonographic examination of the neck and right axillary region showed no signs of regional metastases. The surgical excision of the entire tumor was performed, with the associated subcutaneous tissue and a part of fascia underneath. Results of the histopathological analysis confirmed the diagnosis of hemangiopericytoma. The specimen showed no signs or elements of the neoplastic tissue on the edges of the resection lines. 3 years after the operation, there was found no signs of tumor relapses, regional or systemic metastases. Conclusion: Considering that there are no official clinical guides and protocols for hemangiopericytoma management, as well as the occurrence of cutaneous and subcutaneous hemangiopericytomas is exceptionally rare, more extensive research in this field and more described cases are need to gain a better understanding of that issue.

A system for NO removal from flue gas comprised of partial oxidation by H2O2 and SCR process is proposed in this study. This hybrid system is found to be extremely efficient for deNOx at ...

The work presented in this paper was dedicated to the investigation of the influence of the alkaline treatment parameters on the formation of mesopores in zeolite ZSM-5, SiO2/Al2O3=50. Concentration of NaOH, temperature and tretment duration were varied. The obtained samples were characterized using low temperature nitrogen adsorption, X ray diffraction and solid state 27Al MAS NMR spectroscopy. Formation of mesopores was found to be a process sensitive to changes of treatment parameters, which can lead to creation of hierarchical zeolites with different mesopore surfaces and distributions of pore size diameters. Also, treatment duration was found to have a lesser influence on the process, compared to other two investigated parameters. Mesopore introduction resulted in partial crystallinity reduction, in all modified samples. No significant buildup of extraframework Al was detected. U ovom radu prikazani su rezultati ispitivanja uticaja parametara alkalnog tretmana na formiranje mezopora u zeolitu ZSM-5, SiO2/Al2O3=50. Varirane su koncentracija natrijum hidroksida, temperatura i trajanje tratmana. Uzorci dobijenih hijerarhijskih formi zeolita ZSM-5 okarakterisani su metodama niskotemperaturske adsorpcije azota, rendgenskom difrakcionom analizom i 27Al MAS NMR sprektroskopijom čvrstog stanja. Utvrđeno je da je formiranje mezopora u zeolitu ZSM-5 proces osetljiv na promene ispitivanih parametara i da je moguće kreiranje hijerarhijskih ZSM-5 zeolita sa različitim veličinama mezoporoznih površina i raspodelama dijametara pora. Takođe, utvrđeno je da koncentracija NaOH i temperatura tretmana imaju značajniji uticaj na formiranje mezoporoznosti od trajanja tretmana. Dobijeni rezultati pokazuju da je formiranje mezopora ovim postupkom praćeno delimičnim smanjenjem kristaliniteta uzoraka zeolita. Na osnovu 27Al MAS NMR sprektroskopije zaključeno je da tretman nije doprineo stvaranju značajnih količina vanmrežnog aluminijuma.

Valorization of winery waste is a promising solution for waste management with additional benefit of bioactive compounds isolation. The aim of this study was to analyze the nutritional and bioactive potential of oil derived from Serbian autochthonous grape seed variety Prokupac and to compare it with known international grape varieties. Additionally, two extraction methods (ultrasound assisted extraction and cold pressing) were used in order to determine their influence on physico-chemical and nutritive characteristics of grape seed oil. Different methods, including determination of physicochemical properties, content of bioactive compounds, oxidative stability and antioxidative capacity were used for the characterization of grape seed oils. Results indicated that the higher yield was obtained by ultrasound assisted extraction compared to cold pressing. The application of ultrasound assisted extraction resulted in increased α-tocopherol content and better antioxidant capacity and oxidative stability of oil. Significant differences in bioactive composition were observed for Prokupac seed oil compared to the other grape varieties. Oil extracted from Prokupac grape seed had the lowest content of polyunsaturated and the highest content of saturated fatty acids, the highest content of α-tocopherol and consequently, the best antioxidative capacity. Prokupac grape seed has a great potential for isolation of nutritive and bioactive valuable oil.

Dual templating approach, using hexadecyltrimethylammonium bromide (CTAB), was employed in an attempt to synthesize hierarchical ZSM-5 zeolite. Amount of mesoporogen and the duration of aging of the precursor were varied. Majority of the synthesis routes resulted in phase separation, yielding separate ZSM-5 and amorphous mesoporous material. The relative amounts of the two phases were dependent on the CTAB amount ratio and also significantly on the duration of precursor aging before CTAB addition. One particular combination of the two factors led to the formation of a homogeneous hierarchical form of ZSM-5 with leafy morphology, consisting of intergrown thin crystalline sheets which formed flower-like structures. The hierarchical ZSM-5 possessed significant microporous (≈95 m2/g) and highly developed mesoporous surface (≈470 m2/g), with a relatively broad distribution of mesopore sizes (

Cu-SAPO-34 catalysts with varied Cu loadings were synthesized through ion exchange to study the influence of water on the NH3-SCR reaction. The catalytic activities were evaluated by selective catalytic reduction of NO under a reactant feed in the presence/absence of water. Transient experiments were designed to study the response of NO conversion to the presence of water. H-2-TPR and DFT calculations were performed to study the reducibility of Cu species. NH3-TPD and XPS were conducted to reveal the migration of Cu species. The results show that water could remarkably improve NO reduction activities and the promoting effect is more significant on the catalyst with low Cu loading. Both transient and permanent influences were found in this promoting phenomenon. For the transient influence, water has been proved to accelerate the re-oxidation half-cycle. Moreover, water can enhance the promoting effect of the SCR feed on the migration of Cu species. These unanchored Cu ions migrate to defect sites to form active sites, which lead to a permanent influence of water.

SCR activity of Cu-SAPO-34 catalyst was reduced by alkali metal ions. The alkali metals ions (Li+, Na+ and K+) have shown irregular influences on Cu-SAPO-34. The order of poisoning strengths under 400 °C was found to be: Na+ > K+ > Li+, which is not consistent with the basicities of their corresponding metals. Experimental results and calculations showed that the alkali metal ions readily replace H+ and Cu2+/Cu+ ions. These exchanges result in the loss of Bronsted acid sites and migration of isolated Cu2+ ions in Cu-SAPO-34, which decrease the NH3-SCR activity. Both the basicity and ion diameter will affect the exchanging behavior of an alkali ion. Na+ and Li+ ions will influence both H+ and Cu2+/Cu+ ions but K+ ions only preferably replace the H+. We hypothesize that K+ cannot enter into a small ring (6-membered ring) to replace a Cu2+/Cu+ ion because of its large ion diameter. The displaced Cu2+/Cu+ ions will transfer to adjacent unbonded Al site to form a CuAlO2 species.

Two different ways of extracting antioxidative compounds (including soluble polyphenols) from rusks made from wheat flour with added millet (Panicum miliaceum L.) were compared, i.e., solvent extraction and in vitro digestion. Wheat flour was replaced by millet flour in amounts of 10, 20 or 30 wt. % (per dry mass). Solvent extraction was realized using a mixture of ethanol and water in different percentages, with or without the addition of formic acid. The total content of phenolic compounds (TPC) was determined using Folin– –Ciocalteu reagent, while the antioxidative capacity was measured by the DPPH (2,2-diphenyl-1-picrylhydrazyl) assay. The efficiency of solvent extraction was enhanced by the addition of formic acid. The addition of millet flour in amounts up to 20 % enhanced the antioxidative properties. It was shown that in vitro digestion was more efficient in the extraction of antioxidative compounds, in comparison with solvent extraction. [Project of the Serbian Ministry of Education, Science and Technological Development, Grant no. ON 172018 and Grant no. TR 31005]

The competitive adsorption of aromatic hydrocarbons (benzene, methyl- and ethyl-benzene) and water on FeZSM-5 zeolites have been investigated by means of temperature-programmed desorption coupled with mass spectrometry (TPD/MS). The incorporation of iron in zeolite was done by aqueous ion exchange using dilute solutions of Fe complexes (ferric citrate and ferrous oxalate) and ferric nitrate. Diffuse reflectance UV–Vis spectroscopy and temperature-programmed reduction (TPR) were applied to characterize active sites on investigated zeolites. The existence of different iron species on FeZSM-5 zeolites was revealed. It has been demonstrated that the activity of the Fe exchanged zeolite depends on the iron salt used for ion exchange. The isolated, dispersed ions, which are often considered to be essential for adsorption and catalysis, were obtained with high yield only by ion exchange in the presence of ferrous oxalate. TPD/MS measurements show that aromatic hydrocarbons adsorb on specific, strong active sites in hydrated zeolites. The binding occurred when organic molecules replace water previously adsorbed at the same sites. Benzene showed non-dissociative adsorption/desorption, while new mass fragments were recorded during methyl-benzene and ethyl-benzene desorption implying their dissociative adsorption/desorption on active sites in hydrated zeolites.

Unsaturated fatty acid (FA)–modified nanocellulose (m-NC) shows potential application in improving mechanical properties of unsaturated polyester/m-NC nanocomposites (UPe/m-NC). A polyester matrix is obtained by polycondensation of maleic anhydride and products of poly(ethylene terephthalate) depolymerization with propylene glycol. Two methods of NC modification are performed: direct esterification with oleic acid, linseed, or sunflower oil FAs, and esterification/amidation with maleic acid/ethylene diamine (MA/EDA) bridging group followed by amidation with methyl ester of FAs. Increases of stress at break in the ranges from 148.8% to 181.4% and from 155.8% to193.0% for UPe/m-NC composites loaded with 1 wt% of NC modified directly or via MA/EDA cross-linker, respectively, are obtained. Results of the modeling of tensile modulus, by using the Cox–Krenchel model, show good agreement with experimentally obtained data. The effect of FAs' cross-linking capabilities on the dynamic-mechanical and thermal properties of the UPe/m-NC is studied. Cross-linking density, modulus, and Tg of the nanocomposite show appropriate relation with the unsaturation extent/structure of NC modification. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim Supporting information: [https://hdl.handle.net/21.15107/rcub_dais_3757]

Carqueja (Pterospartum tridentatum) is an endemic species and various bioactive compounds have been identified in its aqueous extract. The aim of this study was to protect the natural antioxidants from the aqueous extract of carqueja by encapsulation in Ca-alginate microbeads and Ca-alginate microbeads containing 10% and 20% (w/v) of inulin. The microbeads produced by electrostatic extrusion technique had an average diameter from 625 μm to 830 μm depending on the portion of inulin. The sphericity factor of the hydrogel microbeads had values between 0.014 and 0.026, while freeze dried microbeads had irregular shape, especially those with no excipient. The reduction in microbeads size after freeze drying process (expressed as shrinkage factor) ranged from 0.338 (alginate microbeads with 20% (w/v) of inulin) to 0.523 (plain alginate microbeads). The expressed radical scavenging activity against ABTS and DPPH radicals was found to be between 30% and 40% for encapsulated extract, while the fresh extract showed around 47% and 57% of radical scavenging activity for ABTS and DPPH radicals, respectively. The correlation between antioxidant activity and the total phenolic content were found to be positive (in both assay methods, DPPH and ABTS), which indicate that the addition of inulin didn't have influence on antioxidant activity. The presence of inulin reduced stiffness of the hydrogel, and protected bead structure from collapse upon freeze-drying. Alginate-inulin beads are envisaged to be used for delivery of aqueous P. tridentatum extract in functional food products.

The clinoptilolite-rich tuff (NZ) from Zlatokop deposit (Vranjska Banja, Serbia) has been studied as a nitrogen carrier for grass production. Mechanism of binding ammonium cations present in water solutions by NZ has been examined as well as possibility of adsorption of ammonia released in fresh cattle manure during its fermentation. The NH4+ binding from solutions proceeds via an ion-exchange process which follows the pseudo-second-order kinetics. Adsorption isotherms studied at 298-318 K follow the Freundlich isotherm equation. The NZ readily adsorbs ammonia liberated from manure and an addition of 10 wt.% of NZ to manure can preserve up to 90% of ammonia. The potential benefit of this effect has been examined in greenhouse pot experiments with the Italian ryegrass (Lolium multiflorum, var. Macho) using three different types of soil (silty, clayey and sandy). The zeta potential measurements show that stability of their colloidal dispersions differs mutually and that addition of the NZ differently affects the stability and nitrogen cycling. All results indicate that NZ can be applied in grass production. [Projekat Ministarstva nauke Republike Srbije, br. 172018 and Norwegian Programme in Higher Education, Research and Development HERD]

Besides its importance concerning fundamental studies on gas adsorption in narrow pores, investigation of commensurate freezing of fluid within the zeolite is of practical importance in application of zeolite in the process of adsorption, separation and catalysis. In this work the adsorption of n-hexane on HZSM-5 and its transition metal ion-exchanged modified forms was studied at 303 K by means of microcalorimetry. The thermal molar entropies of adsorption were calculated and thus, the freezing like behaviour of n-hexane inside the structure of zeolite as a confinement media was noticed. This effect is governed by the attractive interactions between n-hexane molecules and the pore walls, and is also influenced by the length of the pores and the nature of charge-balancing cations. Among the investigated zeolites, solid like phase of n-hexane in the pores of zeolites with Fe2+ ions is the most like a solid n-hexane bulk, while the presence of Cu2+ ions contribute to the lowest ordering obtained solid like phase of n-hexane. [Projekat Ministarstva nauke Republike Srbije, br. 172018]

Room temperature adsorption of CO and N2O using isothermal calorimetry and in situ FTIR spectroscopy on bimetallic and monometallic forms of Cu, Fe and Mn exchanged zeolite ZSM-5 was studied. The two complementary techniques allowed the assessment of the strengths of interactions as well as the identification of the cations active in adsorption. In bimetallic samples containing Cu, a synergistic effect was observed for CO adsorption, i.e higher strengths of adsorption were detected than for corresponding monometallic samples. Such an effect was not detected for N2O. Furthermore, FTIR measurements revealed that N2O adsorption was somewhat restricted for the cation which was introduced the first in bimetallic samples. These findings imply the importance of the order of cation introduction and the procedure of ion exchange process for the adsorptive properties of bimetallic ZSM-5 and, consequently, catalytic reactions where adsorption of N2O is an important reaction step.

In this paper, synthesis of porous wollastonite-based ceramics was reported. Ceramic precursor, methylhydrocyclosiloxane, together with micro-sized CaCO3, was used as starting material. After 20 min of ultrasound treatment, and calcination at 250 oC for 30 min, yeast as a pore-forming agent was added to the as-obtained powders. Sintering regime was set up based on the results obtained by differential thermal analysis. Prepared mixture was pressed into pallets and sintered at 900 oC for 1 h. After the sintering regime, porous wollastonite-based ceramics was obtained. The phase composition of the sintered samples as well as microstructures was analyzed by X-ray diffraction method and SEM. In a batch test, the influence of pH, contact time and initial ion concentration on adsorption efficiency of As+5, Cr+6, and phosphate ions on synthesized wollastonite-based ceramics were studied. Time-dependent adsorption was best described by pseudo-second-order kinetic model and Weber-Morris model that predicted intra-particle diffusion as a rate-controlling step of overall process. High adsorption capacities 39.97, 21.87, and 15.29 mgg-1 were obtained for As+5, Cr+6, and phosphate ions, respectively.

Keeping of red wine in bottles is very important for its maturation and quality. However, there are numerous changes that happen during that period, usually caused by oxidative processes and changes in structure and content of polyphenolic compounds. The goal of this study was to determine the effects of Inactivated dry yeast (IDY) products on aging, phenolics content, colour stability and sensory characteristics of red wine Prokupac (Serbian autochthonous variety). The treatment of wine was done by 3 different IDYP (Lallemand, Canada): Optimum White, Opti Less and Noblesse, applied as 0.2 g/L and 0.4 g /L during 15 days. Subsequently, wine clarification was done, followed by filtration and bottling. Untreated wines were used for comparison. Wine was subjected to accelerated aging (10 days at 55 ° C) and also to normal aging conditions during one year. To determine the influence of IDYP following parameters were monitored: dissolved O2, free and total SO2, sugar free extract, content of total phenolics, flavonoids, flavan-3-ols and anthocyanins, percent of polymeric color, color tint, color intensity and sensory characteristics (Panel method). The obtained results clearly show that IDY products are good scavengers of oxygen and have a positive impact on wine quality preservation and its organoleptic characteristics. However, a slight decrease of polyphenols content was detected.

The influence of modification and vacuum/supercritical CO2 (scCO2) drying methods on the surface properties, morphology and thermal stability of cellulose nanocrystals (NC) was presented in this study. Introduction of reactive vinyl groups on NC surface was performed by either direct esterification with oleic acid, linseed or sunflower oil fatty acids; or by amidation of maleic acid/ethylene diamine with methyl ester of fatty acid. Obtained modified NC (m-NC) were characterized using FTIR and Raman spectroscopy; and by determination of acid, iodine and ester values. Structural analysis of m-NC showed varieties of forms, from spongy to nanostructural non-uniform layered morphology with observable agglomeration, which confirmed morphology dependence on modification/processing methods Thermogravimetry-MS spectrometry showed different thermal stability and degradation pathways of NC/m-NC. Incorporation of 1 wt% of reactive m-NC in unsaturated polyester lead to high performance nanocomposites and contributed to increase of stress at break in the range from 76 to 93%. This is the peer-reviewed version of the article: Rusmirović, J.D., Ivanović, J.Z., Pavlović, V.B., Rakić, V.M., Rančić, M.P., Djokić, V., Marinković, A.D., 2017. Novel modified nanocellulose applicable as reinforcement in high-performance nanocomposites. Carbohydrate Polymers 164, 64–74. [https://doi.org/10.1016/j.carbpol.2017.01.086] Supporting information: [https://hdl.handle.net/21.15107/rcub_dais_5980] Published version: [https://hdl.handle.net/21.15107/rcub_dais_2380]

The goal of this work was to investigate the relationship between antioxidants' content and the oxidative stabilities of grape seed oils obtained from the Cabernet Sauvignon variety. The samples of grape seed oils were obtained by ultrasound assisted extraction. The time of extraction was varied, while the other relevant parameters: extraction temperature, solvent to solid ratio and sonication power were kept constant. For the sake of comparison, the extraction was also done using the conventional Soxhlet method. For all the oil samples obtained, the contents of total phenolic compounds (TPC), alpha-tocopherol and fatty acids were determined using relevant analytic methods. Importantly, in the present study, the modern analytical techniques for estimation of antioxidant capacity (measuring the chemiluminescence intensity of a luminol-hemin solution) and oxidative stability [differential scanning calorimetry (DSC), coupled with thermogravimetry (TG)] were proposed. The obtained results prove that ultrasonic irradiation enables effective extraction of grape seed oil. It was shown that the extractive yields and the amounts of total phenolic compounds and alpha-tocopherol increase with time of extraction; the optimum time was determined. Results obtained in this work show that, for both oxidative stability and antioxidant capacity, TPC have a more important role then alpha-tocopherol.

The surface modification of nanocrystalline TiO2 particles (45 angstrom) with catecholate-type ligands having different electron donating/electron withdrawing substituent groups, specifically 3-methylcatechol, 4-methylcatechol, 3-methoxycatechol, 3,4-dihydroxybenzaldehyde and 4-nitrocatechol, was found to alter the optical properties of nanoparticles in a similar way to catechol. The formation of the inner-sphere charge-transfer (CT) complexes results in a red shift of the semiconductor absorption compared to unmodified nanocrystallites and a reduction of the effective band gap, being slightly less pronounced in the case of electron withdrawing substituents. The investigated ligands have the optimal geometry for binding to surface Ti atoms, resulting in ring coordination complexes of the catecholate type (binuclear bidentate binding-bridging) thus restoring six-coordinated octahedral geometry of surface Ti atoms. From the absorption measurements (Benesi-Hildebrand plot), the stability constants in methanol/water = 90/10 solutions at pH 2 in the order of 10(3) M-1 have been determined. The binding structures were investigated by using FTIR spectroscopy. Thermal stability of CT-complexes was investigated by using TG/DSC/MS analysis. Quantum chemical calculations on model systems using density functional theory (DFT) were performed to obtain the vibrational frequencies of charge transfer complexes, and the calculated values were compared with the experimental data.

Catalytic dehydration of fructose and its conversion to 5-hydroxymethylfurfural was studied using tungstated zirconia oxides, with various tungsten oxide loadings (1–20 wt.%). The samples were prepared by incipient wetness impregnation and thoroughly characterized using a combination of different techniques: structural, thermal and calorimetric analyses. Zirconia was predominantly present in the investigated samples in the tetragonal phase when the WO3 loading was above 10 wt.%. The samples exhibited amphoteric characteristics, as they adsorbed both ammonia and sulfur dioxide on their surface. The number of surface acid sites increased with increasing WO3 content. Fructose dehydration tests evidenced the formation of 5-hydroxymethylfurfural and by-products (formic and levulinic acids). The results show that the ratio of basic to acidic sites of the solid catalysts is the key parameter for the selectivity in 5-HMF, while the global fructose conversion was mainly related to the presence of acid sites of a given strength with 150 > Qdiff > 100 kJ·molNH3− 1.

EAU:ENERGIE+VRA:AAU; In this study, adsorption of salicylic acid, acetylsalicylic acid and atenolol from aqueous solutions onto clinoptilolite modified with sorbed metallic cations (Cu(II), Zn(II), Ni(II) or Mn(II)) have been probed. Natural clays (kaolin and bentonite, pure or ion-exchanged by octadecyl dimethyl benzyl ammonium chloride) have been also probed as adsorbents. The adsorption was studied at 30 degrees C by titration microcalorimetry, employed to obtain the heats evolved as a result of adsorption. Adsorption experiments were performed under the same conditions, the equilibrium adsorbate concentrations were determined by fluorescence spectrophotometry. The maximal adsorption capacities of investigated solids against target pharmaceuticals lie in the range of 10(-5)-10(-6) mol/g. Modified minerals have shown different capacities in comparison with natural ones. The adsorption capacities are dependent on the characteristics of pharmaceutically active compound. The results obtained in this work show that natural materials can be used effectively in the removal of investigated pharmaceuticals by adsorption. (C) 2012 Elsevier Inc. All rights reserved.

Rakic, Vesna Damjanovic, Ljiljana Rac, Vladislav Stosic, Dusan Dondur, Vera Auroux, Aline; The present work is focused on the adsorption of nicotine from aqueous solutions. Based on the data available in the literature, serious concern is claimed regarding the appearance of nicotine in ground, surface and municipal wastewaters. In order to investigate the possibility of abatement by adsorption, three different types of zeolites (BEA, MFI and HEU) have been applied as adsorbents. In addition, the adsorption was per-formed on activated carbon, a solid customarily used for removal of pollutants from water. The adsorption of nicotine was studied by isothermal microcalorimetry, which provided the heats evolved as a result of adsorption. The values of these heats revealed that the investigated solids are energetically heterogeneous for the adsorption of nicotine from aqueous solution. Additionally, the amounts of adsorbed pollutant were determined and presented in the form of adsorption isotherms. The obtained adsorption isotherms were interpreted using Langmuir, Freundlich, and Sips equations; the latter was found to express high level of agreement with experimental data of nicotine adsorption on the investigated solids. The possibilities to regenerate the adsorbents were examined by means of thermogravimetry coupled with mass spectrometry. From all obtained results, it was possible to distinguish zeolite BEA as a material which possesses the capacity for adsorption of nicotine comparable to that of activated carbon. (C) 2009 Elsevier Ltd. All rights reserved.

The present work focuses on the combination of ceria mixed with another oxide from group III, using the sol-gel method. B2O3- Al2O3- Ga2O3- or In2O3-CeO2 mixed oxides have been prepared in order to improve the catalytic properties of these materials. The structural, textural, and surface properties of these catalysts have been fully characterized by means of a variety of techniques (Brunauer-Emmett-Teller, BET; X-ray diffraction analysis, XRD; Raman; scanning electron microscopy, SEM; thermogravimetric analysis, TG; and temperature-programmed reduction/oxidation, TPR-TPO). The highest surface area was achieved for the Al2O3-CeO2 mixed oxide. Only the fluorite structure of CeO2 was observed by XRD for all prepared mixed oxides; the presence of oxygen vacancies was proven by Raman spectroscopy. The acid-base properties were estimated by the adsorption of probe molecules (NH3 and SO2); two methods, microcalorimetry and X-ray photoelectron spectroscopy (XPS), have been employed for that purpose. All investigated mixed oxides express surface amphoteric character; however, it seems that surface basicity is more pronounced than surface acidity. The surface bacisity, which is mainly of the Bronsted type, has been found as dependent on the character of the group III metal. Red-ox properties were investigated for the In2O3-CeO2 sample, the achieved degree of reduction being 34%. TPR/TPO experiments performed up to 830 degrees C irreversibly changed the morphology and the structure of the samples, leading to the crystallization of In2O3.

L-histidine, a naturally occurring amino acid, was incorporated inside the supercages of FAU type zeolite in a form of Me-complex entity (Me = Cu(II), Zn(II), Fe(III)). The preparation was done either by ion-exchange procedure, or previously prepared Me-histidine complex was incorporated into the a cages of Y zeolite by occlusion. The preparation procedure was found to be a very important factor, as well as the amount of metal complex loaded on the zeolite. The characterization of obtained samples was performed using Diffuse Reflectance Ultraviolet-Visible Spectroscopy (DRUV-Vis), 13C MAS NMR and Infrared Spectroscopy (FTIR). It was noticed that 1-hostidine interacted with the zeolitic framework, and with the extra-framework cation, as well. The results obtained by TG-DSC/MAS technique, revealed that the thermal stability of incorporated histidine was increased, in comparison with that one of pure histidine. U ovom radu, Me-histidin (Me = Zn(II), Cu(II), Fe(III)) kompleksi ugrađivani su u strukturu Yzeolita, primenom dva različita postupka: (1) Me-histidin kompleksi su pravljeni u dejonizovanoj vodi i zatim mešani sa NaY zeolitom, (2) histidinje rastvoren u vodi i u rastvor su dodavani jonski izmenjeni Y zeoliti. UV-spektroskopijom tečne faze je utvrđeno da je proces imobilizacije izvršen za 24 h. Ovako dobijem čvrsti materijali su detaljno okarakterisani hemijski i metodama XRD, NMR, IR, DR UV-VIS, dok su njihove termalne stabilnosti ispitivane primenom TG-DSC/MAS tehnike. Dobijem rezultati omogućili su poređenje osobina sintetisanih uzoraka.

The plant alkaloid, nicotine, is a strongly toxic heterocyclic compound: the lethal dose for an adult human being (40-60 mg) is importantly lower in comparison with the other known poisons such as arsenic or strychni­ne. Cigarettes represent "the most toxic and addictive form of nicotine". Besides the negative effects of nicotine on public health produced by self-administration, recently another potentially very dangerous effect has been recognized: because of its miscibility with water, nicotine can be found in industrial wastewaters, and consequently, in groundwater. Therefore, the problem of nicotine removal from aqueous solutions has became an interesting topic. In this work, the removal of nicotine has been probed by adsorption on solid materials. Adsorption of nicotine on different zeolites (clinoptilolite, ZSM-5 and beta zeolite) and on activated carbon was investigated from aqueous solutions, at 298 K. The obtained results are presented as adsorption isotherms: the amount of adsorbed nicotine as a function of equilibrium concentration. These data were obtained from the residual amount of nicotine in the aqueous phase, by the use of UV spectroscopy. The highest amounts of adsorbed nicotine was found for activated carbon and p zeolite (~ mmol·g-1). The attempt to modify the adsorption properties of ZSM-5 zeolite has been also done: ZSM-5 was modified by ion-exchange with VIII group metal (Cu2+ and Fe3+). In addition, the adsorption of nicotine on ZSM-5 zeolite with different Si/Al ratios has been done. It has been noticed that ion-exchange did not improve the adsorption possibilities, while the adsorption was importantly lower in the case of higher silicon content in ZMS-5 structure. 13C NMR spectra were collected for suspensions formed of solid adsorbent and aqueous solution of nicotine; in this way, the part of nicotine molecule which is most probably connected with the adsorbent was recognized. U ovom radu ispitivana je adsorpcija nikotina iz vodenih rastvora na različitim zeolitima (klinoptilolitu, ZSM-5 i beta zeolitu) kao i na aktivnom uglju visoke specifične površine; na 298K. Dobijeni rezultati prikazani su u formi adsorpcionih izotermi: količina adsorbovanog nikotina u funkciji od ravnotežnih koncentracija nikotina. Ovi podaci dobijeni su iz određivanja količine nikotina preostale u vodenoj fazi, metodom UV spektroskopije. Najveće količine adsorbovanog nikotina utvrđene su na aktivnom uglju i beta zeolitu (~ mmol/g). Iz 13C NMR spektara snimljenih iz suspenzije: čvrsti adsorbent-vodeni rastvor nikotina, utvrđen je atom ugljenika preko koga se molekul nikotina najverovatnije vezuje sa površinama zeolita.

Carqueja (Pterospartum tridentatum) is an endemic species and various bioactive compounds have been identified in its aqueous extract. The aim of this study was to protect the natural antioxidants from the aqueous extract of carqueja by encapsulation in Ca-alginate microbeads and Ca-alginate microbeads containing 10% and 20% (w/v) of inulin. The microbeads produced by electrostatic extrusion technique had an average diameter from 625 μm to 830 μm depending on the portion of inulin. The sphericity factor of the hydrogel microbeads had values between 0.014 and 0.026, while freeze dried microbeads had irregular shape, especially those with no excipient. The reduction in microbeads size after freeze drying process (expressed as shrinkage factor) ranged from 0.338 (alginate microbeads with 20% (w/v) of inulin) to 0.523 (plain alginate microbeads). The expressed radical scavenging activity against ABTS and DPPH radicals was found to be between 30% and 40% for encapsulated extract, while the fresh extract showed around 47% and 57% of radical scavenging activity for ABTS and DPPH radicals, respectively. The correlation between antioxidant activity and the total phenolic content were found to be positive (in both assay methods, DPPH and ABTS), which indicate that the addition of inulin didn't have influence on antioxidant activity. The presence of inulin reduced stiffness of the hydrogel, and protected bead structure from collapse upon freeze-drying. Alginate-inulin beads are envisaged to be used for delivery of aqueous P. tridentatum extract in functional food products.

Covalent sidewall functionalization of multiwalled carbon nanotubes (MWCNTs) has been performed using two approaches, direct and indirect cycloaddition through diethyl malonate, based on the Bingel reaction. The results revealed that functionalized MWCNTs demonstrated enhanced electrical properties and significantly lower sheet resistance, especially after electric field thermal assisted annealing at 80 °C was performed. The presence of 1,3-dicarbonyl compounds caused the surface of MWCNTs to be more hydrophilic, approachable for the electrolyte and improved the capacitance performance of Au/MWCNTs electrodes. The modified MWCNTs have been incorporated into nanocomposites by using solution mixing method with polyaniline and drop-casting resulting mixture on the paper substrate. The reduction in the sheet resistance with increasing the content of MWCNTs in the prepared nanocomposite films has been achieved.

In this study, calcium alginate beads immobilizing D-limonene (solid systems) have been manufactured starting from emulsions of this flavor in sodium alginate (liquid systems). The effects of alginate concentration (0.02 and 0.03 g/mL) and flavor content (5 and 10 % w/w) on viscosity, conductivity and stability of emulsions were investigated. The flavor droplets in emulsions are bigger as polymer solution is more concentrated and contains more of the flavor. When emulsions have been subjected to electrostatic extrusion and upon Na+-Ca2+ ion exchange, smaller (similar to 960 to similar to 1450 mm) and less spherical beads were obtained (sphericity factor 0.003-0.21) compared to beads produced by simple dripping technique (without electrostatic field). When wet beads were air dried, they shrunk less if they had higher content of the flavor. Novel mathematical model describing swelling kinetics of dried beads is developed. In this work, D-limonene was efficiently immobilized within Ca-alginate beads (immobilization efficiency similar to 50 to similar to 77%) and its thermal stability was confirmed by TG/MS analysis. This is peer-reviewed version of the artcle: S. Lević, I.P. Lijaković, V. Đorđević, V. Rac, V. Rakić, T.Š. Knudsen, V. Pavlović, B. Bugarski, V. Nedović, Characterization of sodium alginate/d-limonene emulsions and respective calcium alginate/d-limonene beads produced by electrostatic extrusion, Food Hydrocoll. 45 (2015) 111–123 [https://doi.org/10.1016/j.foodhyd.2014.10.001] Published version: [http://cer.ihtm.bg.ac.rs/handle/123456789/1762]

In this work, the values of entropy changes related to n-hexane adsorption onto cation exchanged Y zeolite were calculated from differential heats. Various transition metal cations (Co2+, Ni2+, Zn2+ and Cd2+) were introduced into the lattice of the parent NaY, and the existence of enthalpy-entropy compensation effect related to n-hexane adsorption, id. est, the linearity of -ΔH vs. -ΔS plots was examined. The compensation effect was confirmed for all investigated zeolites. The compensation effect can be comprehended as governed by ion-induced dipole interaction between highly polarizing cationic centers in zeolite and nonopolar n-hexane molecules. Finally, the compensation effect and so the compensation temperature were found to depend on the type of charge-balancing cation (charge, size and electronic configuration). [Projekat Ministarstva nauke Republike Srbije, br. 172018]

Perovskite type catalysts La 0.7 Sr 0.3 Cr 1− x Ru x O 3 (0.025 ≤ x ≤ 0.100) were synthesized by annealing a mixture of metal oxides and carbonates gradually up to 1000 °C in air, and characterized by XRPD, XPS, TPD, SEM-EDS and the van der Pauw method. The CO oxidation activity was investigated in a differential recycle reactor. According to the XRPD results, all samples achieved a perovskite structure, with a small presence of SrCrO 4 phase. The XPS results revealed that the surface composition of all samples differed considerably from the stoichiometric value with an important segregation of strontium and mainly ruthenium with regard to chromium at the surface of the catalysts. The sharp decrease of resistivity with increasing surface concentration of ruthenium and the independence of the resistivity on temperature for the sample with x = 0.100 imply the possible presence of SrRuO 3 , La–Ru–O and highly dispersed RuO 2 (invisible by XRPD), known as good electric conductors, at the surface. The CO oxidation activity increases with increasing the degree of substitution ( x ). The surface concentrations of ruthenium are almost the same in the samples with x = 0.075 and 0.100. Those samples showed the similar values of resistivity in whole investigated temperature range and very close CO oxidation activity, which indicates that the concentration of Ru 4+ in the surface region and its stability are determining factors for the CO oxidation activity. The main results of this study are that ruthenium perovskites have a high thermal stability and CO oxidation activity.

Temperature-programmed desorption coupled with mass spectrometer as a detector (TPD), IR and C-13 NMR measurements are used to study the adsorption of n-hexane on hydrated HZSM-5 and NH(4)ZSM-5 zeolites. The C-13 NMR measurements show that n-hexane can access the pore structure of ZSM-5 zeolites previously saturated with water. TPD spectra of n-hexane are monitored in the temperature region 50-300 degrees C, in the case of fully or partially hydrated samples; two-stage desorption of n-hexane is found. Simultaneous desorption of water and n-hexane in the same temperature region are found, in all investigated samples.

In this work, the free energy changes and entropy changes of adsorption of n-hexane on zeolites of the MxNa87-2xX (M=Co,Ni,Zn,Cd) type were determined using their isosteric sorption heats. It was found that the exchange of Na ions in NaX with bivalent cations (Co, Ni, Zn, Cd) significantly alters the adsorption characteristics of NaX zeolite. The free energy changes and entropy changes of n-hexane adsorption were dependent on the surface coverage and on the nature of the charge-balancing cation. The specific influence of the exchanged cations on the free energy changes and entropy changes of sorption of n-hexane originates from the size, location and electronic configuration of the cation. U ovom radu su određene promene slobodne energije i promena entropije adsorpcije n-heksana na zeolitima tipa MxNa87-2xX (M=Co,Ni,Zn,Cd) na osnovu izosternih toplota sorpcije. Pokazano je da izmena Na+ jona u NaX zeolitu dvovalentnim katjonima (Co,Ni,Zn,Cd) značajno menja adsorpcione karakteristike NaX zeolita. Takođe je utvrđeno da promena slobodne energije i promena entropije adsorpcije n-heksana zavisi i od stepena pokrivenosti površine zeolita.

The active sites of hydrogen-exchanged Y zeolite (HY) and dealuminated (HDY) zeolites are investigated by TPD of carbon monoxide. Only the high temperature TPD spectra of CO (TM»620-690°C) were observed, meaning that CO molecules interact with very strong acid sites. The amounts of CO bonded on these sites are small (less than 1 molecule per unit cell). The strong influence of dealumination on the coverage degree is found. The calculated values for kinetic parameters indicate chemisorption of CO in the investigated systems (Edes»240 kJ mol-1, A»1011 s-1).

EAU:ENERGIE+DST:SBE:VRA:AAU; Mesoporous Nb2O5 MeO2 (Me = Ti, Zr, Ce) mixed oxides were successfully prepared using evaporation-induced self-assembly (EISA) method. The structural and textural properties of these materials have been fully characterized using appropriate techniques (low-temperature adsorption-desorption of nitrogen, thermogravimetric analysis, X-ray diffraction analysis (XRD) transmission electron microscopy (TEM), scanning electron microscopy (SEM) and Raman spectroscopy). Acid-base properties were estimated by adsorption microcalorimetry of NH3 and SO2 molecules in order to determine the population, strength and strength distribution of acidic or basic sites. Formation of mesoporous structure was confirmed by the results of XRD, TEM and BET techniques. Results of adsorption microcalorimetry technique showed that the type of transition metal oxide added to niobia has a decisive role for acidic-basic character of investigated mixed oxides. Among the investigated mixed oxide formulations only Nb2O5-CeO2 was amphoteric, while the other samples showed prominent acidic character. All the investigated materials are catalytically active in fructose dehydration; conversion of fructose and selectivity to 5-hydroxymethylfurfural (5-HMF) and levulinic acid (LA) are proved to be dependant on the number of acidic sites on the surface of catalysts. Furthermore, presence of the basic sites on the surface of the catalyst decreases the activity in the fructose dehydration reaction, as in the case of Nb2O5-CeO2 sample. (C) 2014 Elsevier B.V. All rights reserved.

The acidity of hierarchical USY, Beta and ZSM-5 zeolites obtained by alkaline treatment was investigated. Samples were characterized by low temperature nitrogen adsorption, X ray diffraction and solid-state 27Al MAS NMR. Acidity of parent and mesoporous samples was estimated through the adsorption of typical probe molecules – measurements were conducted in both gas phase (microcalorimetry/volumetry of ammonia adsorption, FTIR spectrometry of pyridine adsorption/desorption) and aqueous phase (calorimetry of phenylethylamine adsorption). Quantitative distributions in strength of the acid sites were determined, as well as acid sites concentrations. No significant changes in total acidity were detected for ZSM-5. Acid sites strength was decreased in modified Beta and USY zeolites. The samples were probed as catalysts for the dehydration of fructose. Higher selectivities towards 5-hydroxymethylfurfural were detected for all modified zeolites, compared to the parent ones.

The interactions of carbon monoxide with Lewis acid sites of zeolites were investigated using microcalorimetric and temperature programmed desorption (TPD) techniques. Carbon monoxide was adsorbed at 25°C on transition-metal ion-exchanged FAU (Y and X) and MOR type zeolites. The differential heats of adsorption ( Q dif ) indicate the heterogeneity of the acid sites, in all the investigated systems. The specific interactions of CO with the strongest acid sites were recognized. The results of TPD confirm that CO molecules were adsorbed on the sites of different strength.

SSCI-VIDE+ATARI+VRA:RAC:OOT:AAU; International audience; In this study, the adsorption of pharmaceutically active compounds - salicylic acid, acetylsalicylic acid, atenolol and diclofenac-Na onto activated carbons has been studied. Three different commercial activated carbons, possessing similar to 650, 900 or 1500 m(2) g(-1) surface areas were used as solid adsorbents. These materials were fully characterized - their textural, surface features and points of zero charge have been determined. The adsorption was studied from aqueous solutions at 303 K using batch adsorption experiments and titration microcalorimetry, which was employed in order to obtain the heats evolved as a result of adsorption. The maximal adsorption capacities of investigated solids for all target pharmaceuticals are in the range of 10(-4) mol g(-1). The obtained maximal retention capacities are correlated with the textural properties of applied activated carbon. The roles of acid/base features of activated carbons and of molecular structures of adsorbate molecules have been discussed. The obtained results enabled to estimate the possibility to use the activated carbons in the removal of pharmaceuticals by adsorption. (C) 2014 Elsevier B.V. All rights reserved.

EAU:ENERGIE+RAC:VRA:DST:AAU; The influence of the alkaline treatment on the acidity of zeolite ZSM-5 (SiO2/Al2O3 = 23, 50 and 80) modified by desilication was investigated. The samples were characterized by X-ray diffraction, low temperature adsorption of nitrogen and solid-state Al-27 MAS NMR. Acidity of the samples was investigated using microcalorimetry-volumetry of ammonia adsorption at 423 K. Acid sites accessibility and intracrystalline diffusion were estimated by the thermokinetic parameter. The desilication process was shown to be Si/Al ratio dependant. Relative enhancement of mesopore surface decreased in the following order of SiO2/Al2O3: 50 >80 >23. Pore size distribution broadened and mesopore sizes increased with increasing Si/Al ratio. For samples with SiO2/Al2O3 = 50 and 80 almost full preservation of acid sites strength and distribution was achieved. Significant alteration of the acidity was found for the mesoporous sample with SiO2/Al2O3 = 23. Thermokinetic parameter values indicate facilitated intracristalline diffusion for mesoporous samples. (C) 2013 Elsevier B.V. All rights reserved.

This chapter presents the fundamentals, the experimental setups and the applications of temperature-programmed desorption (TPD), method used to investigate the events that take place at the surface of solid material while its temperature is changed in a controlled manner. At the beginning, fundamental principles of adsorption and desorption phenomena, as well as the data concerning first experimental setups are given. Further, important information related to the construction of nowadays used equipment and the organization of common experiments are underlined. The significance of data directly obtained from temperature-programmed experiment—TPD profile, which are the area under it and the position of peak maximum, are highlighted. Particular attention is given to the results that can be derived from these data—characterization of active sites that can be found on the surface of solid material and determination of kinetic and thermodynamic parameters of desorption process. In this regard, the influence of important experimental parameters on derived values is explained. Besides, the distinctions between TPD experiments performed in ultra-high vacuum and in the flow systems (differences in experimental setups and in the derivation of kinetic and thermodynamic parameters) are explained. Also, the modification of temperature-programmed techniques, known as temperature-programmed oxidation and temperature-programmed reduction are shortly explained and compared with temperature-programmed desorption method. In the end, a brief comparison of the TPD and adsorption calorimetry, two most widely used techniques for the study of acid/base properties of catalysts, is given.

This text reviews the possibilities to apply microcalorimetry and thermo-analytical methods of analysis in the fields related to the environment pollution. At the beginning, short overview of chemical species that can be found as common pollutants in the atmosphere, waters and soils is given. Further, it is shown how the mentioned techniques can be applied for direct investigation of some event that includes specific pollutants. The possibilities to use calorimetry and thermo-analytical methods for the characterization of substances used either as adsorbents or catalysts in the processes of pollutants’ abatement are presented. Besides, it is shown how all mentioned methods can provide data useful in the removal of certain pollutant. The importance of microcalorimetry and thermo-analytical methods in environment protection is underlined.

Članak se bavi sudijskim građanskopravnim imunitetom (privilegijom) sa istorijskog, uporednopravnog i pozitivnopravnog aspekta. Razvoj ideje, zakonodavstva i prakse ograničene odgovornosti sudije za naknadu štete prikazan je na primerima vodećih država anglo-američkog i evropskog kontinentalnopravnog kruga. Razmatran je i uticaj evropskih sudskih instanci na obim sudijskog imuniteta u nekim nacionalnim pravima. Posebno je prikazan razvoj sudijskog imuniteta u Srbiji – naročito najnovije težnje ka njegovom proširenju., Until today, judicial immunity has been explained by the need to secure independence of judges and courts. High requirements for election of judges and the demanding conditions for their dismissal were until recently considered to be sufficient to guarantee legality of judicial conduct of proceedings and correctness of judicial adjudication, so that the idea of disciplinary liability of judges had difficulties finding its advocates in the states successors of former Yugoslavia. In cases where judges cause damages by their work, the damage will be regularly compensated by the state, which can, in turn, under specific conditions raise a recourse claim against the judge. This paper outlines some important points in the historic development of judicial immunity for damage compensation in England, USA, Germany and France. The contemporary laws and regulations and the leading cases of these countries are presented as well, including some relevant information on situation in some other European countries. The main argument for establishing judicial immunity in civil cases, ie the need to guarantee judicial independence, is met in this paper by criticism, in particular from the viewpoint of current and announced legislative developments in Serbia. The author initiates her critical analysis by the submission that direct judicial liability is currently only an exception to the rule that the state covers the damages caused by judicial work, while the right of recourse of the state against a judge is generally limited to cases in which the damages were caused intentionally or by gross negligence. National legislations display a trend of further limiting civil liability of judges, and thereby also of the state, for compensation of damages, effectively broadening judicial immunity. On the contrary, European Court of Human Rights and the Court of Justice of the EU tend to extend the liability of the state, and thereby also the civil liability of judges. The binding force of the European judicial institutions for the national courts has in recent times led to effective limitation of judicial immunity. In her concluding remarks, the author presents and explains her analysis of most recent tendencies in the development of judicial immunity in civil matters in Serbia. They are the following: under current rules of civil procedure, injured parties have difficulties securing their right of access to court when they decide to sue the state for damages caused by judges; the right of state to recourse claims against judges is planned to be limited, in the announced amendments of the Law on Judges, only to cases where judges have committed damages intentionally. Such an approach is considered to be inappropriate. It can secure neither real judicial independence, nor the rule of law. In addition, this approach discourages formation of reliable corpus of case law regarding civil immunity of judges.