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11.
Bajuk-Bogdanović Danica Holclajtner-Antunović Ivanka Jovanović Zoran Mravik Željko Krstić Jugoslav Uskoković-Marković Snežana Vujković Milica 《Journal of Solid State Electrochemistry》2019,23(9):2747-2758
Journal of Solid State Electrochemistry - The synergistic effects between two Keggin-type heteropoly acids (HPAs) and carbon surface were examined and elucidated. An improved high rate capability... 相似文献
12.
Slobodan??iri?Email authorView authors OrcID profile Violeta?Miti? Sne?ana?Jovanovi? Marija?Ili? Jelena?Nikoli? Gordana?Stojanovi? Vesna?Stankov Jovanovi? 《Mikrochimica acta》2018,185(12):556
The authors report on a novel sorbent (thermally treated natural zeolite; clinoptilolite) for use in dispersive micro-solid phase extraction (D-μ-SPE) of polycyclic aromatic hydrocarbons (PAHs) from water samples. The method was applied to the D-μ-SPE of 16 priority PAHs which then were quantified by gas chromatography with mass spectrometric detection (GC-MS). The method was validated in terms of specificity and selectivity, linearity and linear range, accuracy, precision, uncertainty, limits of detection and quantification. Figures of merit include (a) linear analytical ranges between 2.08 and 208 ppb, and (b) detection limits in the range from 0.01 to 0.92 ppb. The method was successfully applied to the determination of PAHs in river waters. 相似文献
13.
Goran M. Petrović Marija D. Ilić Vesna P. Stankov-Jovanović Gordana S. Stojanović Snežana Č. Jovanović 《Natural product research》2018,32(3):331-334
Phytochemical analysis by GC and GC/MS of the essential oil samples obtained from fresh shoots and flowers of Saponaria officinalis L. allowed the identification of 96 components in total, comprising 94.7% and 86.0% of the total oils compositions, respectively. Regarding the shoots essential oil, the major of 87 identified volatile compounds were phytol (14.1%), tricosane-6,8-dione (13.4%), patchouli alcohol (7.9%) and tricosane (7.2%), whereas patchouli alcohol (20.0%), heneicosane (11.5%) and tricosane (8.4%) were dominant among the 66 volatiles in the flower oil. Nonterpenoid compounds had the highest contribution in S. officinalis shoots essential oil (53.7%), while in the flower oil, constituents were almost evenly distributed between the oxygenated sesquiterpenoid (41.2%) and nonterpenoid compounds (39.5%). 相似文献
14.
Hydrogen Bonding between Metal‐Ion Complexes and Noncoordinated Water: Electrostatic Potentials and Interaction Energies 下载免费PDF全文
Jelena M. Andrić Majda Z. Misini‐Ignjatović Dr. Jane S. Murray Prof. Peter Politzer Prof. Snežana D. Zarić 《Chemphyschem》2016,17(13):2035-2042
The hydrogen bonding of noncoordinated water molecules to each other and to water molecules that are coordinated to metal‐ion complexes has been investigated by means of a search of the Cambridge Structural Database (CSD) and through quantum chemical calculations. Tetrahedral and octahedral complexes that were both charged and neutral were studied. A general conclusion is that hydrogen bonds between noncoordinated water and coordinated water are much stronger than those between noncoordinated waters, whereas hydrogen bonds of water molecule in tetrahedral complexes are stronger than in octahedral complexes. We examined the possibility of correlating the computed interaction energies with the most positive electrostatic potentials on the interacting hydrogen atoms prior to interaction and obtained very good correlation. This study illustrates the fact that electrostatic potentials computed for ground‐state molecules, prior to interaction, can provide considerable insight into the interactions. 相似文献
15.
Zorica Vujić Milkica Crevar Vladimir Obradović Vesna Kuntić Snežana Uskoković-Marković 《Chromatographia》2009,70(7-8):1221-1225
A rapid and simple liquid chromatographic method with UV detection has been developed for the determination of hydrochlorothiazide (HCTZ), cilazapril (CL) and its active metabolite cilazaprilat (CLT) in urine. Sample preparation for urine consisted of solid-phase extraction using styrene-divinylbenzene (SDB-2) cartridges. The chromatographic system was a Zorbax Eclipse XDB-C18 column with a mixture of methanol and 10 mM phosphate buffer, pH 2.3 with gradient (20 to 60% of methanol) as mobile phase at a flow rate of 1.0 mL min?1. The detection was performed at the wavelength of 206 nm. Enalapril maleat was used as an internal standard. The detector response was linear in the range of 2.4–30.0, 1.6–15.0 and 1.8–20.0 μg mL?1 for HCTZ, CL and CLT, respectively. LOQ was determined to be 2.4, 1.6 and 1.8 μg mL?1 for HCTZ, CL and CLT, respectively. Both intra- and inter-day precision were within acceptable limits. The method has been applied to urine samples obtained from three hypertensive patients after intake of HCTZ and CL therapeutic dose. 相似文献
16.
Mariusz P. Mitoraj Goran V. Janjić Vesna B. Medaković Dušan Ž. Veljković Artur Michalak Snežana D. Zarić Miloš K. Milčić 《Journal of computational chemistry》2015,36(3):171-180
The water/aromatic parallel alignment interactions are interactions where the water molecule or one of its O? H bonds is parallel to the aromatic ring plane. The calculated energies of the interactions are significant, up to ΔECCSD(T)(limit) = ?2.45 kcal mol?1 at large horizontal displacement, out of benzene ring and CH bond region. These interactions are stronger than CH···O water/benzene interactions, but weaker than OH···π interactions. To investigate the nature of water/aromatic parallel alignment interactions, energy decomposition methods, symmetry‐adapted perturbation theory, and extended transition state‐natural orbitals for chemical valence (NOCV), were used. The calculations have shown that, for the complexes at large horizontal displacements, major contribution to interaction energy comes from electrostatic interactions between monomers, and for the complexes at small horizontal displacements, dispersion interactions are dominant binding force. The NOCV‐based analysis has shown that in structures with strong interaction energies charge transfer of the type π → σ*(O? H) between the monomers also exists. © 2014 Wiley Periodicals, Inc. 相似文献
17.
Najat Aburas Aleksandar Loli? Nikola Stevanovi? Tatjana Tripkovi? Sne?ana Nikoli?-Mandi? Rada Bao?i? 《Journal of the Iranian Chemical Society》2012,9(6):859-864
This study describes the effects of the substituents on electrochemical behavior and antioxidant activity of the six tetradentate Schiff bases, containing ethane-1,2-diamine or propane-1,2-diamine as the amine part and pentane-2,4-dione and/or 1-phenylbutane-1,3-dione as ??-diketone, and corresponding copper(II) complexes. Cyclic voltammograms of these compounds were recorded in dimethylsulfoxide and 0.1?M sodium perchlorate as supporting electrolyte with glassy carbon as working electrode at different scan rates. The voltammograms of Schiff bases alone showed only one irreversible peak. Voltammograms recorded for complexes showed the presence of quasi-reversible processes taking place at the metal center and reversible process at the ligand part. Both steric and inductive effects of substituents and structure of imine bridge of Schiff base ligands as well as complexes were discussed. These effects appear relevant for the antioxidant activity. Antioxidant activity of the investigated compounds expressed as Trolox equivalent antioxidant capacity is also discussed. The electrochemical behavior showed a high correlation with the antioxidant activity for investigated compounds. 相似文献
18.
Zorica D. Petrović Jelena Đorović Dušica Simijonović Snežana Trifunović Vladimir P. Petrović 《Chemical Papers》2018,72(9):2171-2180
N-Salicylidene and N-vanillidene anil Schiff bases SB-1–5 were evaluated for their iron-coordinating properties. For this purpose, reactions with Fe(III) chloride were performed. The obtained results showed that salicylaldehyde bases SB-1 and SB-2 are the best coordinating ligands among the investigated SBs. The corresponding complexes are obtained in good yield and investigated using UV–Vis spectrophotometry and IR spectroscopy. The inhibitory potential of SB-1–5 against iron-containing enzyme lipoxygenase (LOX) was also tested. Salicylidene bases exerted better activity then vanilliden. The cytotoxic in vitro activities against human breast carcinoma MDA-MB-231 and human colon carcinoma HCT-116 cell lines were determined. Based on these results, SB-1 and SB-2 can be considered as interesting compounds for further in vivo investigations. 相似文献
19.
Neda O. Đorđević Miroslav M. Novaković Dalibor M. Stanković Jelena J. Mutić Snežana B. Pajović 《Natural product research》2018,32(3):247-251
The overall aim of this paper was to compare the multielement composition and antioxidant capacity of two Montenegrin Merlot wines obtained from specific vine clones (VCR1 and VCR 101) along with commercial Merlot wine throughout the consecutive vintages in 2010 and 2011. Elemental composition was analysed using inductively coupled plasma optical emission spectrometry (ICP-OES) and inductively coupled plasma mass spectrometry (ICP-MS). Additionally, antioxidant capacity was assessed by cyclic voltammetry. VCR 1 wine from 2011 stood out for its elemental composition. On the other hand, antioxidant capacity of VCR 101 wines was the highest one for the both vintages. According to the experimental data obtained, all three wines are good source of essential elements and products with a significant antioxidant activity and specific geographical origin. 相似文献
20.
Jovana Lj Pavlović Snežana M. Mitić Milan N. Mitić Aleksandra N. Pavlović Ružica J. Micić Milan B. Stojković 《Analytical letters》2018,51(9):1417-1432
The contents of 17 elements in thirteen strawberry cultivars grown in the five districts of Southern Serbia were determined using inductively coupled plasma optical emission spectrometry (ICP-OES). The most abundant elements are K (875–1148 mg?·?kg?1 fresh weight), P (307–664 mg?·?kg?1 fresh weight), Ca (192–256 mg?·?kg?1 fresh weight), and Mg (111–189 mg?·?kg?1 fresh weight) in all samples. Strawberries were also found to be a good source of Sr (8.05–18.6 mg?·?kg?1 fresh weight) and Fe (3.09–10.4 mg?·?kg?1 fresh weight). The contents of As and Cd were below the detection limit (0.0828 mg?·?kg?1 and 0.0205 mg?·?kg?1, respectively) in all strawberry samples, while the contents of Ni, Cr, and Cu were below the recommended tolerable levels proposed by Joint Food and Agriculture Organization of the United Nations and World Health Organization Expert Committee on Food Additives, and did not a pose a health risk for the consumer. The application of Duncan’s test showed significant differences between contents of analyzed elements in all strawberry cultivars. The highest mean levels of analyzed elements were detected in strawberries grown in the Topli?ki, Jablani?ki, and P?injski districts. The spike recovery test was used to verify the accuracy of the method, and the spike recovery was in the range 93.8–107.8%. The contents of the metals in strawberry samples were also comparable with values previously reported in the literature. 相似文献