NEPRAVIČNA PORESKA KONKURENCIJA U EVROPSKOJ UNIJI

The article deals with the issue of harmful tax competition, as a very bad phenomenon related with the globalization of the economic activities, and searching for the most adequate measures to prevent its appearance. I take into consideration the activities of the European Commission and the OECD, from nineteens till nowadays and measures that each of these organizations have taken to prevent further appearance of harmful tax practices and to lessen bad consequences of their existence.Rad se bavi pitanjem nepravične poreske konkurencije, kao izrazito štetne pojave povezane sa globalizacijom privredne aktivnosti, i pronalaženjem najadekvatnijih mera za njeno sprečavanje. Razmatraju se aktivnosti Evropske komisije i OECD-a, počev od devedesetih godina XX veka do današnjih dana i mere koje svaka od ovih organizacija preduzima na sprečavanju daljeg pojavljivanja nepravičnih poreskih režima i otklanjanje, odnosno ublažavanje štetnih posledica njihovog postojanja

Efikasno premeštanje push-pull 5-supstituisanih 4-oksotiazolidina indukovano piridinijum-hidrobromid-perbromidom pod homogenim reakcionim uslovima

Pyridinium hydrobromide perbromide (PHBP) is a highly efficient reagent for the conversion of 5-substituted-2-alkylidene-4-oxothiazolidine derivatives to the corresponding thiazolidines with two fully delocalized exocyclic double bonds at the C(2) and C(5) positions. This conversion as a two-step bromination-rearrangement process occurs in acetonitrile under homogeneous reaction conditions.Piridinijum-hidrobromid-perbromid (PHBP) je veoma efikasan reagens za konverziju 5-supstituisanih-2-alkiliden-4-oksotiazolidinskih derivata u odgovarajuće tiazolidine sa dve potpuno delokalizovane egzociklične dvogube veze u položajima C(2) i C(5). Ova konverzija je dvofazni proces bromovanja i premeštanja koji se odvija u acetonitrilu pod homogenim reakcionim uslovima

Controlling qubit arrays with anisotropic XXZ Heisenberg interaction by acting on a single qubit

We investigate anisotropic XXZ Heisenberg spin-1/2 chains with control fields acting on one of the end spins, with the aim of exploring local quantum control in arrays of interacting qubits. In this work, which uses a recent Lie-algebraic result on the local controllability of spin chains with "always-on” interactions, we determine piecewise-constant control pulses corresponding to optimal fidelities for quantum gates such as spin-flip (NOT), controlled-NOT (CNOT), and square-root-of-SWAP (). We find the minimal times for realizing different gates depending on the anisotropy parameter Δ of the model, showing that the shortest among these gate times are achieved for particular values of Δ larger than unity. To study the influence of possible imperfections in anticipated experimental realizations of qubit arrays, we analyze the robustness of the obtained results for the gate fidelities to random variations in the control-field amplitudes and finite rise time of the pulses. Finally, we discuss the implications of our study for superconducting charge-qubit array

Optimization and implementation of the wavelet based algorithms for embedded biomedical signal processing

Existing biomedical wavelet based applications exceed the computational, memory and consumption resources of low-complexity embedded systems. In order to make such systems capable to use wavelet transforms, optimization and implementation techniques are proposed. The Real Time QRS Detector and De-noising Filter are developed and implemented in 16-bit fixed point microcontroller achieving 800 Hz sampling rate, occupation of less than 500 bytes of data memory, 99.06% detection accuracy, and 1 mW power consumption. By evaluation of the obtained results it is found that the proposed techniques render negligible degradation in detection accuracy of -0.41% and SNR of -2.8%, behind 2-4 times faster calculation, 2 times less memory usage and 5% energy saving. The same approach can be applied with other signals where the embedded implementation of wavelets can be beneficial

Choline chloride-based deep eutectic solvents in CaO-catalyzed ethanolysis of expired sunflower oil

Choline chloride (ChCl)-based deep eutectic solvents (DESs) with different amides or polyols as hydrogen bond donors were tested as cosolvents in the ethanolysis of expired sunflower oil catalyzed by either calcined or non-calcined CaO. These cosolvents promoted the ethanolysis by a successful activation of non-calcined CaO, which was ascribed to the CaCO3 and Ca(OH)2 dissolution from the surface of the solid catalyst particles. With both calcined and non-calcined CaO, the polyol-based solvents gave higher fatty acid ethyl esters (FAEE) content than the amide-based solvents. Among the amide-based DESs, choline chloride:urea (ChCl:U) was the most efficient activator of non-calcined CaO. Choline chloride:ethylene glycol (ChCl:EG) and choline chloride:propylene glycol (ChCl:PG) were more efficient than choline chloride:glycerol (ChCl:G) even with non-calcined CaO. However, ChCl:G might be more suitable than the others since the use of glycerol, a by-product of the ethanolysis, could reduce the overall biodiesel production costs. FTIR and XRD analyses of the used and separated CaO were performed in order to get more insight into the catalytically active phase(s). Also, the mechanisms of the CaO activation in the presence of the DESs were considered. The phase separation of the reaction mixture was faster in the presence of the DESs. Since ChCl:U and ChCl:G DESs are nontoxic, biodegradable, biorenewable and “green” solvents and provide the elimination of the calcination step of CaO, thus reducing the overall process costs, the non-calcined CaO catalytic systems with these DESs are recommended for further optimization. © 2018 Elsevier B.V.Published version: [https://hdl.handle.net/21.15107/rcub_dais_3694]This is the peer reviewed version of the following article: Troter, D.Z., Todorović, Z.B., Đokić-Stojanović, D.R., Veselinović, L.M., Zdujić, M.V., Veljković, V.B., 2018. Choline chloride-based deep eutectic solvents in CaO-catalyzed ethanolysis of expired sunflower oil. Journal of Molecular Liquids 266, 557–567. [https://doi.org/10.1016/j.molliq.2018.06.106]Supplementary information: [https://hdl.handle.net/21.15107/rcub_dais_3772

Examination of elements of galactocentric orbits of the thin disk stars from the solar neighbourhood by varying potential of the galaxy.

Циљ ове дисертације је да се одреди вредност динамичких константи...The goal of this dissertation is to determine values of local dynamical constants. This goal is achieved through examination of multiple samples of selected stars near the Sun. The selection is done by using planar and vertical eccentricities as sampling criteria. The solution for calculating eccentricities is given. In the next step a large sample of stars is selected by defining upper limits for eccentricities and vertical amplitude. Then nested subsamples are formed in two ways: in the first one upper eccentricity limit is subjected to decreasing, in the other one this is the case with upper amplitude of oscillations perpendicular to the plane. The values of the local dynamical constants are deduced by analysing this material

Photochemistry of methyl hypobromite (CH₃OBr): excited states and photoabsorption spectrum

The singlet and triplet excited states of CH3OBr with excitation energies up to ∼9.5 eV are studied using the multi-reference configuration interaction with singles and doubles method (MRCI-SD) and several single-reference methods, including time-dependent density functional theory (TD-DFT), coupled-cluster (linear-response CC2 and equation-of-motion CCSD and CCSD(T)), and algebraic diagrammatic construction (ADC(2)). Among the single-reference methods, coupled-cluster gives vertical excitation energies and oscillator strengths comparable to the MRCI-SD values for the majority of excited states. The absorption cross section in the gas phase in the region between 2 and 8.5 eV was simulated with CCSD using the nuclear ensemble approach. The computed spectrum predicts two intense absorption bands. The first band, peaked at ∼7.0 eV, is induced by Rydberg excitation. The second band has a strong overlap between a broad σσ* transition and three Rydberg transitions, resulting in two peaks at 7.7 and 7.9 eV. The spectrum also features a low-intensity band peaking at ∼4.6 eV due to nσ* excitation. The intensity of this band is influenced by spin–orbit coupling effects. We analyzed the dissociation pathways along the O–Br and C–O coordinates by computing rigid potential energy curves of the ground and the lowest-lying singlet and triplet excited states, and discussed the possible dissociation products. Due to the specific electronic structure of the excited states, characterized by multireference, double excitations, and Rydberg states occurring in the low-energy region, their correct description along dissociation coordinates is feasible only with MRCI-SD

La-doped and La/Mn-co-doped Barium Titanate Ceramics

Barium titanate ceramics doped with 0.3 mol.% lanthanum and co-doped with 0.3 mol.% lanthanum and 0.05 mol.% manganese were investigated. The powders were prepared by a modified polymeric precursor method based on the Pechini process. The ceramics were obtained by sintering at 1300 degrees C for 8 h. The influence of dopants on structural changes and grain size reduction was analyzed. The presence of dopants influenced the tetragonality of the barium titanate crystal structure. Reduction of polygonal grain size with dopant addition was noticed. In the doped ceramics, characteristic phase transitions were shifted to lower temperatures in comparison with pure barium titanate. The dielectric permittivity value showed the tendency of a slight increase with lanthanum addition and further increase with adding of manganese. La as a single dopant increased the diffuseness of phase transitions indicating the formation of a diffuse ferroelectric material but in the co-doped ceramics the phase transition diffuseness decreased. The resistivity of the co-doped ceramics was higher than for lanthanum doped ceramics, indicating possible segregation of manganese at grain boundaries that influenced the total resistivity of the material

Uticaj kosolvenata na etanolizu suncokretovog ulja katalizovanoj kalcijum-oksidom: doktorske disertacije

In this dissertation, the influence of different organic solvents (triethanolamine, diethanolamine, ethylene glycol, methyl ethyl ketone, n-hexane, triethylamine, ethylene glycol dimethyl ether, glycerol, tetrahydrofuran and dioxane) as cosolventethanolysis of sunflower oil catalyzed by calcinated CaO. Ethanolysis was performed as a heterogeneous base-catalyzed process in which calcinated CaO in a stirred batch reactor was used as a catalyst. The reaction conditions were: temperature 70 °C, ethanol:oil molar ratio 12:1, catalyst concentration 1.374 mol·dm-3 and cosolvent amount 20% by weight of oil. Without cosolvent, the reaction is relatively slow, because the EEMK content of 89.7 ± 1.73% was obtained only after 4 h of reaction. Of the cosolvents used, only diethanolamine, triethanolamine and ethylene glycol had a positive effect on the rate of ethanolysis reaction, with the use of triethanolamine and ethylene glycol achieved the highest EEMK content of 93.1±2.1 and 94.1± 1.5%, respectively, after 0,5 h reaction. Based on the experimental results, triethanolamine and the cosolvent that had the greatest positive effect on the rate of the transesterification reaction of the safety profile were selected, triethanolamine was selected as the best cosolvent of the reaction ethanolysis reaction catalyzed by CaO. The reaction with triethanolamine was optimized with respect to temperature (61,6-78,4 °C), ethanol:oil molar ratio (7:1-17:1) and cosolvent amount (3-36%, by weight of oil) using a central composite rotatable experimental design (RCCD) in combination with a response surface methodology (RSM). The optimal reaction conditions are: molar ratio ethanol:oil 9:1, temperature 75 °C and cosolvent amount 30% ( to the mass of oil), where the predicted value of EEMK content after only 20 min of reaction was 98,8%, while the experimentally obtained value was 97,9 ± 1,3%. High EEMK contents were also obtained during the application of expired sunflower oil, hemp oil and waste lard. X-ray diffraction analysis (XRD) was used to understand the structural changes of CaO catalysts. The CaO catalyst could be used without any additional treatment in two consecutive cycles. Due to the leaching of calcium into the product, an additional purification process must be included in the entire production process

Vodonična veza u push-pull 5-supstituisanim 2-alkiliden-4-oksotiazolidinima: 1H-NMR spektroskopsko proučavanje

Application of dynamic H-1-NMR spectroscopy added to the understanding of the hydrogen bonds existing in the structurally related 5-substituted-2-alklidene-4-oxothiazolidines in polar and apolar solvents. The equilibrated mixtures of these topical push-pull alkenes in CDCl3 consist of the intramolecularly H-bonded (E)-isomer and intermolecularly H-bonded (Z)-isomer in varying proportions which depend on the solvent polarity. For the representative of the series. (Z)-2-(5-ethoxycarbonylmethyl-4-oxothiazolidin-2-ylidene)-1-phenylethanone, a concentration effect on the degree of intermolecular hydrogen bonding in apolar CDCl3 has been studied.Primenom dinamičke 1H-NMR spektroskopije došlo se do boljeg razumevanja o vrsti vodoničnih veza koje postoje u strukturno sličnim 5-supstituisanim 2-alkiliden-4-oksotiazolidinima u polarnim i apolarnim rastvaračima. Uravnotežene smese ovih tipičnih push-pull alkena u CDCl3 sadrže (E)-izomer vezan intramolekulskom vodoničnom vezom kao i intermolekulski vodoničnom vezom vezan (Z)-izomer u različitim odnosima, koji zavise od polarnosti rastvarača. U slučaju tipičnog predstavnika serije (Z)-2-(5-etoksikarbonilmetil-4-oksotiazolidin- 2-iliden)-1-feniletanona uticaj koncentracije na stepen stvaranja intermolekulske vodonične veze u apolarnom CDCl3 je takođe proučavan