Read by QxMD icon Read

Acta Chimica Slovenica

Stanislav Južnič
For the first time a complete list of Tesla's High School professors is provided. The excellency of his lecturers of chemistry and related sciences is put into the limelight. The books and articles about chemistry which Tesla read in his High School times are focused together with the related published works of his teachers. The pioneering spectroscopic research of Kirchhoff and Bunsen began in Tesla's early youth and had a considerable impact on Tesla's professors, especially on Martin Sekulić.
2016: Acta Chimica Slovenica
Boris Kolar, Lovro Arnuš, Boštjan Križanec, Willie Peijnenburg, Mojca Kos Durjava
The selective uptake of polybrominated diphenyl ethers (PBDEs) by oligochaetes makes it possible to assess the bioaccumulation of individual congeners in commercial mixtures. Twenty-one congeners from three BDE commercial mixtures (TBDE-71, TBDE-79 and TBDE-83R) and as individual congeners (BDE-77, BDE-126, BDE-198 and BDE-204) were tested on Tubifex tubifex in accordance with the OECD TG 315 "Bioaccumulation in Sediment-Dwelling Benthic Oligochaetes". All the congeners that were spiked in the sediment were detected at the end of the uptake phase and at the end of the experiment...
2016: Acta Chimica Slovenica
Jin-Xian Lei, Jing Wang, Yang Huo, Zhonglu You
A hydrated hydrazone compound, 4-fluoro-N'-(2-hydroxy-3-methoxybenzylidene)benzohydrazide monohydrate (H2L · H2O), was prepared and characterized by elemental analysis, HRMS, IR, UV-Vis and 1H NMR spectroscopy. Reaction of H2L, kojic acid (5-hydroxy-2-(hydroxymethyl)-4H-pyran-4-one; Hka) and VO(acac)2 in methanol afforded a novel oxidovanadium(V) complex, [VO(ka)L]. The complex was characterized by elemental analysis, IR, UV-Vis and 1H NMR spectroscopy. Thermal analysis was also performed. Structures of H2L and the complex were further confirmed by single crystal structural X-ray diffraction...
2016: Acta Chimica Slovenica
Milena Ivanović, Maša Islamčević Razboršek, Mitja Kolar
Several phenolic acids (PAs), caffeic, vanillic, syringic, p-coumaric and ferulic acid, found in Slovenian red wines were studied using gas chromatography and mass spectrometry. For isolation of the PAs from wine samples, solid phase extraction using hydrophilic modified styrene - HLB cartridges was used. The bound PAs were extracted after basic hydrolysis and o-coumaric acid was used as the internal standard. The developed method was validated and the linear concentration range for all analytes was from 1 to 100 mg L-1 with correlation coefficients above 0...
2016: Acta Chimica Slovenica
Kirila Stojnova, Petya Racheva, Vidka Divarova, Kristina Bozhinova, Vanya Lekova
The complex formed between an anionic chelate of Mo(VI)-3,5-dinitrocatechol (3,5-DNC) with the cation of 3,3'-(3,3'-dimethoxy-4,4'-biphenylene)bis(2,5-diphenyl-2H-tetrazolium chloride) (Blue Tetrazolium Chloride, BTC) in the liquid-liquid extraction system Mo(VI)-3,5-DNC-BTC-H2O-CHCl3 was studied. The optimum conditions for the complex formation and extraction of the ion-associated complex were established by spectrophotometry. The molar ratio of the reagents was determined by independent methods. The validity of Beer's law was checked and some analytical characteristics were calculated...
2016: Acta Chimica Slovenica
Zuhal Yolcu, Serkan Demir, Ömer Andaç, Orhan Büyükgüngör
A novel trinuclear copper(II) complex [Cu3(μ-Cl)2Cl4(1-Vim)6] with monodentate 1-vinylimidazole (1-Vim) and chloro ligands has been prepared and experimentally characterized by elemental analysis, thermogravimetry (TGA, DTG, DTA), X-ray single crystal diffractometry, TOF-MS and FT-IR spectroscopies. The electronic and structural properties of the complex were further investigated by DFT/TD-DFT methods. Density functional hybrid method (B3LYP) was applied throughout the calculations. The calculated UV-Vis results based on TD-DFT approach were simulated and compared with experimental spectrum...
2016: Acta Chimica Slovenica
Oleksii Antypenko, Sergiy Kovalenko, Bakhtiyor Rasulev, Jerzy Leszczynski
Chemical compounds with tetrazole ring are very interesting systems that can be valuable in pharmaceutical and clinical applications, especially as anticancer agents. In this work, novel 6-N-R-tetrazolo[1,5-c]quinazolin-5(6H)-ones were synthesized. A large set of IR, LC-, EI-MS, 1H, 13C NMR and elemental analysis data were collected and evaluated for their structures and purity. Details of synthesis, namely the N-alkylation, are discussed, including reactions with secondary and tertiary amides. Four new synthesized compounds (2...
2016: Acta Chimica Slovenica
Mohammad Ali Ghasemzadeh, Mohammad Hossein Abdollahi-Basir
A practical, simple and efficient method for the synthesis of polysubstituted dihydropyridines was described via multicomponent reactions of aldehydes, arylamines, dimethyl acetylenedicarboxylate and malononitrile/ethyl acetoacetate in the presence of Fe3O4@SiO2-NH2 nanocomposites. The present methodology provides a novel and efficient method for the synthesis of dihydropyridine derivatives with some advantages, such as excellent yields, short reaction times, recoverability and low catalyst loading. The nanomagnetic catalyst could be readily recovered using an external magnet and reused several times without any significant loss in activity...
2016: Acta Chimica Slovenica
Nawel Khelloul, Khaled Toubal, Nadia Benhalima, Rachida Rahmani, Abdelkader Chouaih, Ayada Djafri, Fodil Hamzaoui
The title compound (Z)-5-(4-chlorobenzylidene)-3-(2-ethoxyphenyl)-2-thioxothiazolidin-4-one (CBBTZ) was characterized by X-ray single crystal diffraction, 1H NMR and 13C NMR spectra. Theoretical investigations were carried out using HF and DFT levels of theory at 6-31G(d,p) basis set. The X-ray structure is compared with that computed. The calculated geometrical parameters are in good agreement with those determined by X-ray diffraction. The dihedral angle between the two benzene rings is 16.89(5)° indicating that the structure is non planar...
2016: Acta Chimica Slovenica
A Essam Soylem, G Mohammed Assy, M Ghania Morsi
A series of pyrimidine and thiazine derivatives was synthesized by one-pot reaction of cyclopentanone with a mixture of an aromatic aldehyde, namely o-anisaldehyde, and different ureas, namely urea, guanidine and thiourea, respectively. Furthermore, cycloaddition reaction of active methylene reagents, namely acetyl acetone, malononitrile, ethyl cyanoacetate, cyanoacetamide and N-phenyl cyanoacetamide with 2,6-bis(2-methoxybenzylidene)cyclohexanone afforded chromene and quinoline derivatives in basic medium...
2016: Acta Chimica Slovenica
Parvanak Keveh Boroujeni, Zahra Heidari, Reza Khalifeh
A novel multiwalled carbon nanotube catalyst with -SO3H functional groups was easily prepared from its starting materials and used as an efficient heterogeneous catalyst for one-pot Knoevenagel condensation, Michael addition, and cyclodehydration of 5,5-dimethyl-1,3-cyclohexanedione (dimedone) with various aromatic aldehydes. Using this method 1,8-dioxo-octahydroxanthenes were obtained in excellent yields at room temperature. The present method is superior in terms of reaction temperature, reaction time, easy work-up, high yields, and ease of recovery of catalyst...
2016: Acta Chimica Slovenica
Ruby Rani, Ashwani Kumar, Tanu Sharma, Balwinder Saini, Rajinder Kumar Bamezai
The volumetric, acoustic and viscometric methods are used for investigating the interactions of L-aspartic acid (Asp) in aqueous solution of 1,2-propanediol (PD) over a temperature of (298.15, 303.15 and 308.15) K at atmospheric pressure. Using the experimental results, the apparent molar volume, Vφ, limiting apparent molar volume, V0φ, the slope, Sv, and partial molar volume of transfer, V0φ,tr, have been calculated from density data. The apparent molar isentropic compressibility, K φ,s, limiting apparent molar isentropic compressibility, K0φ,s, its slope, Sk, and partial molar compressibility of transfer, K0φ,s, tr, have been calculated from speed of sound data...
2016: Acta Chimica Slovenica
Lara Ulčakar, Tomaž Rejec, Anton Ramšak
The ratio of conductances through carbon-ring based molecules are calculated for various positions of source-drain electrode leads on the molecule. These ratios are usually integers the so-called magic numbers. We find that deviations of the magic number ratios are either zero or quadratic in ratios of tight-binding model parameters.
2016: Acta Chimica Slovenica
Joachim Maier
The vast majority of electrochemical processes can be modelled by resistors and capacitors. These will then be, in addition to usual circuit elements, electrochemical and chemical resistors or chemical capacitors. The paper shows the significance of understanding these parameters and their connections in given systems for a variety of timely scientific examples. This rationale mirrors one of the intellectual facets, if not the most important one, of Janko Jamnik's scientific work.
2016: Acta Chimica Slovenica
Robert Dominko, Manu U M Patel, Marjan Bele, Stane Pejovnik
The electrochemical characteristics of sulfurized polyacrylonitrile composite (PAN/S) cathodes were compared with the commonly used carbon/S-based composite material. The difference in the working mechanism of these composites was examined. Analytical investigations were performed on both kinds of cathode electrode composites by using two reliable analytical techniques, in-situ UV-Visible spectroscopy and a four-electrode Swagelok cell. This study differentiates the working mechanisms of PAN/S composites from conventional elemental sulphur/carbon composite and also sheds light on factors that could be responsible for capacity fading in the case of PAN/S composites...
2016: Acta Chimica Slovenica
Hao Zheng, Rui Wang, Jieyun Zheng, Jian Gao, Hong Li
The electronic and ionic conductivity of the LiF-Ti nanocomposite films prepared by the co-sputtering have been investigated by the method of impedance spectrum (IS), current-voltage curves (IV) and isothermal transient ionic current (ITIC) measurements. It is found that the ionic conductivity of the obtained LiF-Ti nanocomposite film is very low. After electrochemical and chemical lithiation, ionic conductivities of the lithiated composite films are increased to be 10-3 and 10-4 S/cm separately. This phenomenon indicates that the phase boundary between LiF and Ti could be the ionic conducting channels for external lithium in the LiF-Ti nanocomposite...
2016: Acta Chimica Slovenica
Ingrid Milošev, Nataša Kovačević, Anton Kokalj
We report on the combined experimental and computational study of imidazole- and benzimidazole-based corrosion inhibitors containing methyl and/or mercapto groups. Electrochemical measurements and long-term immersion tests were performed on iron in NaCl solution, whilst computational study explicitly addresses the molecular level details of the bonding on iron surface by means of density functional theory calculations (DFT). Experimental data were the basis for the determination of inhibition efficiency and mechanism...
2016: Acta Chimica Slovenica
Dajana Japić, Marjan Marinšek, Zorica Crnjak Orel
The influence of ZnO nanoparticles on the thermal degradation behavior of poly(methyl methacrylate) (PMMA) was tested using thermoanalytical techniques. The studied materials were investigated using TG, DTA, EGA, XRD, SEM and TEM. The ZnO nanoparticles were synthesized via precipitation by adding LiOH into Zn2+ water/ethylene glycol solutions. The ZnO-PMMA nanocomposites were prepared by adding the appropriate amount of ZnO into MMA and subsequent MMA radical polymerization. According to the experimental results and model-free isoconversional activation energy calculations, the addition of ZnO into PMMA played a double role...
2016: Acta Chimica Slovenica
Mogens B Mogensen, Erik Hennesø
Lithium anodes passivated by LiCl layers in different types of liquid cathodes (catholytes) based on LiAlCl4 in SOCl2 or SO2 have been studied by means of impedance spectroscopy. The impedance spectra have been fitted with two equivalent circuits using a nonlinear least squares fit program. Information about the ionic conductivity and the structure of the layers has been extracted. A new physical description, which is able to explain the circuit parameters, is proposed. It assumes that the LiCl-layer contains a large number of narrow tunnels and cracks filled with liquid catholyte...
2016: Acta Chimica Slovenica
Juergen Fleig, Alexander Schmid, Ghislain M Rupp, Christoph Slouka, Edvinas Navickas, Lukas Andrejs, Herbert Hutter, Lukas Volgger, Andreas Nenning
The oxygen stoichiometry of mixed conducting oxides depends on the oxygen chemical potential and thus on the oxygen partial pressure in the gas phase. Also voltages may change the local oxygen stoichiometry and the amount to which such changes take place is quantified by the chemical capacitance of the sample. Impedance spectroscopy can be used to probe this chemical capacitance. Impedance measurements on different oxides ((La,Sr)FeO3-δ = LSF, Sr(Ti,Fe)O3-δ = STF, and Pb(Zr,Ti)O3 = PZT) are presented, and demonstrate how the chemical capacitance may affect impedance spectra in different types of electrochemical cells...
2016: Acta Chimica Slovenica
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"