TY  - JOUR
AU  - Petkovska, M
AU  - Petkovska, Ljubica T.
PY  - 2006
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/2975
AB  - The concept of higher order frequency response functions, used for investigation of weekly nonlinear systems by frequency response techniques, is applied to investigation of membrane systems. Isothermal permeation of single gases through non-porous and porous membranes is analysed for three transport mechanisms: solution-diffusion, pore-surface diffusion, and viscous-flow. In the course of definition of the transmembrane transport in dynamic conditions, a new concept of generalized membrane permeability, defined as an indefinite sequence of the permeabilities of the first, second, third,...order, dependent on the equilibrium and transport parameters of the membrane in steady-state, is introduced. A simple two-reservoir system, with variation of the volume of one reservoir, is defined and its first and second order frequency response functions are derived. It is shown that these functions can be used for identification of the transport mechanism, i.e., of the corresponding model and for estimation of the model parameters: permeabilities of different orders, as well as the separate values of the relevant equilibrium and transport parameters.
T2  - Separation Science and Technology
T1  - Application of nonlinear frequency response to investigation of membrane transport
VL  - 41
IS  - 1
SP  - 43
EP  - 72
DO  - 10.1080/01496390500445782
ER  - 

@article{
author = "Petkovska, M and Petkovska, Ljubica T.",
year = "2006",
abstract = "The concept of higher order frequency response functions, used for investigation of weekly nonlinear systems by frequency response techniques, is applied to investigation of membrane systems. Isothermal permeation of single gases through non-porous and porous membranes is analysed for three transport mechanisms: solution-diffusion, pore-surface diffusion, and viscous-flow. In the course of definition of the transmembrane transport in dynamic conditions, a new concept of generalized membrane permeability, defined as an indefinite sequence of the permeabilities of the first, second, third,...order, dependent on the equilibrium and transport parameters of the membrane in steady-state, is introduced. A simple two-reservoir system, with variation of the volume of one reservoir, is defined and its first and second order frequency response functions are derived. It is shown that these functions can be used for identification of the transport mechanism, i.e., of the corresponding model and for estimation of the model parameters: permeabilities of different orders, as well as the separate values of the relevant equilibrium and transport parameters.",
journal = "Separation Science and Technology",
title = "Application of nonlinear frequency response to investigation of membrane transport",
volume = "41",
number = "1",
pages = "43-72",
doi = "10.1080/01496390500445782"
}

Petkovska, M.,& Petkovska, L. T.. (2006). Application of nonlinear frequency response to investigation of membrane transport. in Separation Science and Technology, 41(1), 43-72.
https://doi.org/10.1080/01496390500445782

Petkovska M, Petkovska LT. Application of nonlinear frequency response to investigation of membrane transport. in Separation Science and Technology. 2006;41(1):43-72.
doi:10.1080/01496390500445782 .

Petkovska, M, Petkovska, Ljubica T., "Application of nonlinear frequency response to investigation of membrane transport" in Separation Science and Technology, 41, no. 1 (2006):43-72,
https://doi.org/10.1080/01496390500445782 . .

TY  - JOUR
AU  - Trtica, Milan
AU  - Tarasenko, Victor F.
AU  - Gaković, Biljana M.
AU  - Fedenev, AV
AU  - Petkovska, Ljubica T.
AU  - Radak, Bojan
AU  - Lipatov, EI
AU  - Shulepov, MA
PY  - 2005
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/2934
AB  - Interactions of a transversely excited atmospheric (TEA) CO2 laser and an excimer XeCl laser, pulse durations similar to 2 mu s (initial spike FWHM similar to 100 ns) and similar to 20 ns (FWHM), respectively, with polycrystalline titanium nitride (TiN) coating deposited on high quality steel AISI 316, were studied. Titanium nitride was surface modified by the laser beams, with an energy density of 20.0 J/cm(2) (TEA CO2 laser) and 2.4 J/cm(2) (XeCl laser), respectively. The energy absorbed from the CO2 laser beam is partially converted to thermal energy, which generates a series of effects such as melting, vaporization of the molten material, shock waves, etc. The energy from the excimer XeCl laser primarily leads to fast and intense target evaporation. The calculated maximum temperatures on the target surface were 3770 and 6300 K for the TEA CO2 and XcCl lasers, respectively. It is assumed that the TEA CO2 laser affects the target deeper, for a longer time than the XeCl laser. The effects of the XeCl laser are confined to a localized area, near target surface, within a short time period. Morphological modifications of the titanium nitride surface can be summarized as follows: (i) both lasers produced ablation of the TiN coating in the central zone of the irradiated area and creation of grainy structure with near homogeneous distribution; (ii) a hydrodynamic feature, like resolidified droplets of the material, appeared in the surrounding peripheral zone; (iii) the process of irradiation, in both cases, was accompanied by appearance of plasma in front of the target. Target color modifications upon laser irradiation indicate possible chemical changes, possibly oxidation. (c) 2005 Elsevier B.V. All rights reserved.
T2  - Applied Surface Science
T1  - Surface modifications of TiN coating by pulsed TEA CO2 and XeCl lasers
VL  - 252
IS  - 2
SP  - 474
EP  - 482
DO  - 10.1016/j.apsusc.2005.01.029
ER  - 

@article{
author = "Trtica, Milan and Tarasenko, Victor F. and Gaković, Biljana M. and Fedenev, AV and Petkovska, Ljubica T. and Radak, Bojan and Lipatov, EI and Shulepov, MA",
year = "2005",
abstract = "Interactions of a transversely excited atmospheric (TEA) CO2 laser and an excimer XeCl laser, pulse durations similar to 2 mu s (initial spike FWHM similar to 100 ns) and similar to 20 ns (FWHM), respectively, with polycrystalline titanium nitride (TiN) coating deposited on high quality steel AISI 316, were studied. Titanium nitride was surface modified by the laser beams, with an energy density of 20.0 J/cm(2) (TEA CO2 laser) and 2.4 J/cm(2) (XeCl laser), respectively. The energy absorbed from the CO2 laser beam is partially converted to thermal energy, which generates a series of effects such as melting, vaporization of the molten material, shock waves, etc. The energy from the excimer XeCl laser primarily leads to fast and intense target evaporation. The calculated maximum temperatures on the target surface were 3770 and 6300 K for the TEA CO2 and XcCl lasers, respectively. It is assumed that the TEA CO2 laser affects the target deeper, for a longer time than the XeCl laser. The effects of the XeCl laser are confined to a localized area, near target surface, within a short time period. Morphological modifications of the titanium nitride surface can be summarized as follows: (i) both lasers produced ablation of the TiN coating in the central zone of the irradiated area and creation of grainy structure with near homogeneous distribution; (ii) a hydrodynamic feature, like resolidified droplets of the material, appeared in the surrounding peripheral zone; (iii) the process of irradiation, in both cases, was accompanied by appearance of plasma in front of the target. Target color modifications upon laser irradiation indicate possible chemical changes, possibly oxidation. (c) 2005 Elsevier B.V. All rights reserved.",
journal = "Applied Surface Science",
title = "Surface modifications of TiN coating by pulsed TEA CO2 and XeCl lasers",
volume = "252",
number = "2",
pages = "474-482",
doi = "10.1016/j.apsusc.2005.01.029"
}

Trtica, M., Tarasenko, V. F., Gaković, B. M., Fedenev, A., Petkovska, L. T., Radak, B., Lipatov, E.,& Shulepov, M.. (2005). Surface modifications of TiN coating by pulsed TEA CO2 and XeCl lasers. in Applied Surface Science, 252(2), 474-482.
https://doi.org/10.1016/j.apsusc.2005.01.029

Trtica M, Tarasenko VF, Gaković BM, Fedenev A, Petkovska LT, Radak B, Lipatov E, Shulepov M. Surface modifications of TiN coating by pulsed TEA CO2 and XeCl lasers. in Applied Surface Science. 2005;252(2):474-482.
doi:10.1016/j.apsusc.2005.01.029 .

Trtica, Milan, Tarasenko, Victor F., Gaković, Biljana M., Fedenev, AV, Petkovska, Ljubica T., Radak, Bojan, Lipatov, EI, Shulepov, MA, "Surface modifications of TiN coating by pulsed TEA CO2 and XeCl lasers" in Applied Surface Science, 252, no. 2 (2005):474-482,
https://doi.org/10.1016/j.apsusc.2005.01.029 . .

TY  - JOUR
AU  - Radak, Bojan
AU  - Petkovska, MT
AU  - Trtica, Milan
AU  - Miljanić, Šćepan S.
AU  - Petkovska, Ljubica T.
PY  - 2004
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/6404
AB  - Detection of specific molecules in the atmosphere is motivated by the need for monitoring the emission of industrial pollutants. CO2-laser photoacoustic (PA) spectroscopy was used here to obtain coincidence spectra of the vapours of three organic solvents: trichloroethylene (TCE), benzene, and dioxan. Spectra of coincidences were obtained as a function of total pressure, adding dry air to the vapour of the solvents up to 1000 mbar. A narrow cavity photoacoustic cell with window acoustic buffers was built for improved sensitivity, and is reported here. The vapour molecules studied do have some significant absorption in the CO2-laser region, or close to it, but that fact does not necessarily lead to usable coincidences with the narrow laser lines. The results reveal several prominent coincidences that can be used for practical purposes, especially in the case of trichloroethylene. (C) 2003 Elsevier B.V. All rights reserved.
T2  - Analytica Chimica Acta
T1  - Photoacoustic study of CO2-laser coincidences with absorption of some organic solvent vapours
VL  - 505
IS  - 1
SP  - 67
EP  - 71
DO  - 10.1016/S0003-2670(03)00572-5
ER  - 

@article{
author = "Radak, Bojan and Petkovska, MT and Trtica, Milan and Miljanić, Šćepan S. and Petkovska, Ljubica T.",
year = "2004",
abstract = "Detection of specific molecules in the atmosphere is motivated by the need for monitoring the emission of industrial pollutants. CO2-laser photoacoustic (PA) spectroscopy was used here to obtain coincidence spectra of the vapours of three organic solvents: trichloroethylene (TCE), benzene, and dioxan. Spectra of coincidences were obtained as a function of total pressure, adding dry air to the vapour of the solvents up to 1000 mbar. A narrow cavity photoacoustic cell with window acoustic buffers was built for improved sensitivity, and is reported here. The vapour molecules studied do have some significant absorption in the CO2-laser region, or close to it, but that fact does not necessarily lead to usable coincidences with the narrow laser lines. The results reveal several prominent coincidences that can be used for practical purposes, especially in the case of trichloroethylene. (C) 2003 Elsevier B.V. All rights reserved.",
journal = "Analytica Chimica Acta",
title = "Photoacoustic study of CO2-laser coincidences with absorption of some organic solvent vapours",
volume = "505",
number = "1",
pages = "67-71",
doi = "10.1016/S0003-2670(03)00572-5"
}

Radak, B., Petkovska, M., Trtica, M., Miljanić, Š. S.,& Petkovska, L. T.. (2004). Photoacoustic study of CO2-laser coincidences with absorption of some organic solvent vapours. in Analytica Chimica Acta, 505(1), 67-71.
https://doi.org/10.1016/S0003-2670(03)00572-5

Radak B, Petkovska M, Trtica M, Miljanić ŠS, Petkovska LT. Photoacoustic study of CO2-laser coincidences with absorption of some organic solvent vapours. in Analytica Chimica Acta. 2004;505(1):67-71.
doi:10.1016/S0003-2670(03)00572-5 .

Radak, Bojan, Petkovska, MT, Trtica, Milan, Miljanić, Šćepan S., Petkovska, Ljubica T., "Photoacoustic study of CO2-laser coincidences with absorption of some organic solvent vapours" in Analytica Chimica Acta, 505, no. 1 (2004):67-71,
https://doi.org/10.1016/S0003-2670(03)00572-5 . .

TY  - JOUR
AU  - Trtica, Milan
AU  - Gaković, Biljana M.
AU  - Petkovska, Ljubica T.
AU  - Tarasenko, Victor F.
AU  - Fedenev, AV
AU  - Lipatov, EI
AU  - Shulepov, MA
PY  - 2004
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/2752
AB  - Interaction of a transversely excited atmospheric (TEA) CO2 and excimer-KrCl laser, pulse duration similar to2 mus (FWHM of initial spike similar to100 ns) and similar to12 ns (FWHM), respectively, with polycrystalline titanium nitride (TiN) coating deposited on high quality steels, was studied. The results have shown that the titanium nitride was surface modified by the laser beam, with an energy density (ED) of 43.0 J/cm(2) (TEA CO2 laser system) and 3.3 J/cm(2) (KrCl system), respectively. The energy absorbed from the CO2 laser beam is partially converted to thermal energy, which generates a series of effects such as melting, vaporization of the molten material, shock waves, etc. The energy from the excimer-KrCl laser primarily leads to a fast and intense target evaporation. Calculated maximal temperatures, on the target surface, were 3940 and 8000 K for the TEA CO2 and the KrCl lasers, respectively. It is assumed that TEA CO2 laser,affects, the target deeper, during a longer time than the KrCl laser. The effects of the KrCl laser are confined to a localized area, near target surface, in the course of short time. The following morphological changes of titanium nitride surface were observed: (i) both types of laser caused ablation of the TiN coating in the central zone of the irradiated area, (ii) appearance of a hydrodynamic feature like resolidified droplets of material in the surrounding outer zone (cracking) in the case of the TEA CO2 laser, and (iii) appearance of wave-like microstructures (consisting of periodic parallel fringes with a period of about 20 microns) in the case of KrCl laser. Formation of the wave-like microstructures is discussed in the context of laser-induced periodic surface structure (LIPSS) effects and diffraction phenomena. The process of the CO2 and KrCl laser interaction with titanium nitride were typically accompanied by plasma formation. Plasma appeared above the target after about 40 and 1 laser pulse, respectively. (C) 2003 Elsevier B.V. All rights reserved.
T2  - Applied Surface Science
T1  - Surface modifications of TiN coating by the pulsed TEA CO2 and KrCl laser
VL  - 225
IS  - 1-4
SP  - 362
EP  - 371
DO  - 10.1016/j.apsusc.2003.10.048
ER  - 

@article{
author = "Trtica, Milan and Gaković, Biljana M. and Petkovska, Ljubica T. and Tarasenko, Victor F. and Fedenev, AV and Lipatov, EI and Shulepov, MA",
year = "2004",
abstract = "Interaction of a transversely excited atmospheric (TEA) CO2 and excimer-KrCl laser, pulse duration similar to2 mus (FWHM of initial spike similar to100 ns) and similar to12 ns (FWHM), respectively, with polycrystalline titanium nitride (TiN) coating deposited on high quality steels, was studied. The results have shown that the titanium nitride was surface modified by the laser beam, with an energy density (ED) of 43.0 J/cm(2) (TEA CO2 laser system) and 3.3 J/cm(2) (KrCl system), respectively. The energy absorbed from the CO2 laser beam is partially converted to thermal energy, which generates a series of effects such as melting, vaporization of the molten material, shock waves, etc. The energy from the excimer-KrCl laser primarily leads to a fast and intense target evaporation. Calculated maximal temperatures, on the target surface, were 3940 and 8000 K for the TEA CO2 and the KrCl lasers, respectively. It is assumed that TEA CO2 laser,affects, the target deeper, during a longer time than the KrCl laser. The effects of the KrCl laser are confined to a localized area, near target surface, in the course of short time. The following morphological changes of titanium nitride surface were observed: (i) both types of laser caused ablation of the TiN coating in the central zone of the irradiated area, (ii) appearance of a hydrodynamic feature like resolidified droplets of material in the surrounding outer zone (cracking) in the case of the TEA CO2 laser, and (iii) appearance of wave-like microstructures (consisting of periodic parallel fringes with a period of about 20 microns) in the case of KrCl laser. Formation of the wave-like microstructures is discussed in the context of laser-induced periodic surface structure (LIPSS) effects and diffraction phenomena. The process of the CO2 and KrCl laser interaction with titanium nitride were typically accompanied by plasma formation. Plasma appeared above the target after about 40 and 1 laser pulse, respectively. (C) 2003 Elsevier B.V. All rights reserved.",
journal = "Applied Surface Science",
title = "Surface modifications of TiN coating by the pulsed TEA CO2 and KrCl laser",
volume = "225",
number = "1-4",
pages = "362-371",
doi = "10.1016/j.apsusc.2003.10.048"
}

Trtica, M., Gaković, B. M., Petkovska, L. T., Tarasenko, V. F., Fedenev, A., Lipatov, E.,& Shulepov, M.. (2004). Surface modifications of TiN coating by the pulsed TEA CO2 and KrCl laser. in Applied Surface Science, 225(1-4), 362-371.
https://doi.org/10.1016/j.apsusc.2003.10.048

Trtica M, Gaković BM, Petkovska LT, Tarasenko VF, Fedenev A, Lipatov E, Shulepov M. Surface modifications of TiN coating by the pulsed TEA CO2 and KrCl laser. in Applied Surface Science. 2004;225(1-4):362-371.
doi:10.1016/j.apsusc.2003.10.048 .

Trtica, Milan, Gaković, Biljana M., Petkovska, Ljubica T., Tarasenko, Victor F., Fedenev, AV, Lipatov, EI, Shulepov, MA, "Surface modifications of TiN coating by the pulsed TEA CO2 and KrCl laser" in Applied Surface Science, 225, no. 1-4 (2004):362-371,
https://doi.org/10.1016/j.apsusc.2003.10.048 . .

TY  - JOUR
AU  - Nešković, Olivera M.
AU  - Veljković, Miomir V.
AU  - Veličković, Suzana
AU  - Petkovska, Ljubica T.
AU  - Perić-Grujić, Aleksandra A.
PY  - 2003
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/2605
AB  - Ionization energies of hypervalent Li2F, Li2Cl and Na2Cl molecules detected by surface ionization electron impact neutralization mass spectrometry are reported. The ionization energies were 3.78 +/- 0.2 eV for Li2F, 4.93 +/- 0.2 eV for Li2Cl, and 4.21 +/- 0.2 eV for Na2Cl. The ionization energies (IE) agree with theoretical ionization energies calculated by ab initio methods,(1) supporting the theoretical prediction that Li2F has a hyperlithiated configuration in which the odd electron delocalizes over the two lithiums and with photoionization measurement.(2) The first ionization energy of Na2Cl was experimentally confirmed earlier(3-7) and for Li2Cl as well.(8) We have developed and used this new approach for the problem-in the present work ions were first formed by surface ionization, followed by electron attachment (neutralization). Copyright (C) 2002 John Wiley Sons, Ltd.
T2  - Rapid Communications in Mass Spectrometry
T1  - Ionization energies of hypervalent Li2F, Li2Cl and Na2Cl molecules obtained by surface ionization electron impact neutralization mass spectrometry
VL  - 17
IS  - 3
SP  - 212
EP  - 214
DO  - 10.1002/rcm.896
ER  - 

@article{
author = "Nešković, Olivera M. and Veljković, Miomir V. and Veličković, Suzana and Petkovska, Ljubica T. and Perić-Grujić, Aleksandra A.",
year = "2003",
abstract = "Ionization energies of hypervalent Li2F, Li2Cl and Na2Cl molecules detected by surface ionization electron impact neutralization mass spectrometry are reported. The ionization energies were 3.78 +/- 0.2 eV for Li2F, 4.93 +/- 0.2 eV for Li2Cl, and 4.21 +/- 0.2 eV for Na2Cl. The ionization energies (IE) agree with theoretical ionization energies calculated by ab initio methods,(1) supporting the theoretical prediction that Li2F has a hyperlithiated configuration in which the odd electron delocalizes over the two lithiums and with photoionization measurement.(2) The first ionization energy of Na2Cl was experimentally confirmed earlier(3-7) and for Li2Cl as well.(8) We have developed and used this new approach for the problem-in the present work ions were first formed by surface ionization, followed by electron attachment (neutralization). Copyright (C) 2002 John Wiley Sons, Ltd.",
journal = "Rapid Communications in Mass Spectrometry",
title = "Ionization energies of hypervalent Li2F, Li2Cl and Na2Cl molecules obtained by surface ionization electron impact neutralization mass spectrometry",
volume = "17",
number = "3",
pages = "212-214",
doi = "10.1002/rcm.896"
}

Nešković, O. M., Veljković, M. V., Veličković, S., Petkovska, L. T.,& Perić-Grujić, A. A.. (2003). Ionization energies of hypervalent Li2F, Li2Cl and Na2Cl molecules obtained by surface ionization electron impact neutralization mass spectrometry. in Rapid Communications in Mass Spectrometry, 17(3), 212-214.
https://doi.org/10.1002/rcm.896

Nešković OM, Veljković MV, Veličković S, Petkovska LT, Perić-Grujić AA. Ionization energies of hypervalent Li2F, Li2Cl and Na2Cl molecules obtained by surface ionization electron impact neutralization mass spectrometry. in Rapid Communications in Mass Spectrometry. 2003;17(3):212-214.
doi:10.1002/rcm.896 .

Nešković, Olivera M., Veljković, Miomir V., Veličković, Suzana, Petkovska, Ljubica T., Perić-Grujić, Aleksandra A., "Ionization energies of hypervalent Li2F, Li2Cl and Na2Cl molecules obtained by surface ionization electron impact neutralization mass spectrometry" in Rapid Communications in Mass Spectrometry, 17, no. 3 (2003):212-214,
https://doi.org/10.1002/rcm.896 . .

TY  - JOUR
AU  - Petkovska, Menka
AU  - Petkovska, Ljubica T.
PY  - 2003
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/2639
AB  - One of the characteristic examples of the inability of the classical linear frequency response (FR) method to identify the correct kinetic mechanism is adsorption of some substances (p-xylene, 2-butane, propane or n-hexane) on silicalite-1. The linear FR resulted with bimodal FR characteristic functions, which fitted equally well to three different kinetic models: nonisothermal micropore diffusion, two independent isothermal diffusion processes, and an isothermal diffusion-rearrangement process. We show that the second order frequency response functions (FRFs), obtained from the nonlinear FR, can be used for discrimination among these three mechanisms. Starting from the nonlinear models, we derive the theoretical expressions for the first and second order FRFs corresponding to these three mechanisms and show that different shapes of the second order FRFs are obtained for each mechanism. This would enable identification of the real mechanism from nonlinear FR data.
T2  - Adsorption
T1  - Use of nonlinear frequency response for discriminating adsorption kinetics mechanisms resulting with bimodal characteristic functions
VL  - 9
IS  - 2
SP  - 133
EP  - 142
DO  - 10.1023/A:1024241326422
ER  - 

@article{
author = "Petkovska, Menka and Petkovska, Ljubica T.",
year = "2003",
abstract = "One of the characteristic examples of the inability of the classical linear frequency response (FR) method to identify the correct kinetic mechanism is adsorption of some substances (p-xylene, 2-butane, propane or n-hexane) on silicalite-1. The linear FR resulted with bimodal FR characteristic functions, which fitted equally well to three different kinetic models: nonisothermal micropore diffusion, two independent isothermal diffusion processes, and an isothermal diffusion-rearrangement process. We show that the second order frequency response functions (FRFs), obtained from the nonlinear FR, can be used for discrimination among these three mechanisms. Starting from the nonlinear models, we derive the theoretical expressions for the first and second order FRFs corresponding to these three mechanisms and show that different shapes of the second order FRFs are obtained for each mechanism. This would enable identification of the real mechanism from nonlinear FR data.",
journal = "Adsorption",
title = "Use of nonlinear frequency response for discriminating adsorption kinetics mechanisms resulting with bimodal characteristic functions",
volume = "9",
number = "2",
pages = "133-142",
doi = "10.1023/A:1024241326422"
}

Petkovska, M.,& Petkovska, L. T.. (2003). Use of nonlinear frequency response for discriminating adsorption kinetics mechanisms resulting with bimodal characteristic functions. in Adsorption, 9(2), 133-142.
https://doi.org/10.1023/A:1024241326422

Petkovska M, Petkovska LT. Use of nonlinear frequency response for discriminating adsorption kinetics mechanisms resulting with bimodal characteristic functions. in Adsorption. 2003;9(2):133-142.
doi:10.1023/A:1024241326422 .

Petkovska, Menka, Petkovska, Ljubica T., "Use of nonlinear frequency response for discriminating adsorption kinetics mechanisms resulting with bimodal characteristic functions" in Adsorption, 9, no. 2 (2003):133-142,
https://doi.org/10.1023/A:1024241326422 . .

TY  - JOUR
AU  - Stojić, Dragica Lj.
AU  - Miljanić, Šćepan S.
AU  - Grozdić, Tomislav D.
AU  - Petkovska, Ljubica T.
AU  - Jaksic, MM
PY  - 2000
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/2351
AB  - Single Ti and Ni metals, their intermetallic phases (stable and unstable) and alloys along the Ti-Ni phase diagram, have been investigated as cathode materials for separation of hydrogen isotopes (protium and deuterium, H/D) by water electrolysis from alkaline solutions. The HID separation factors obtained were compared with the hydridic features and electrocatalytic properties for the hydrogen evolution (HER), enthalpies of intermetallic formation, and in common with similar behavior of transition elements along the Periodic Table, therefrom a close correlation amongst them resulted. The Ti-Ni intermetallic phases, as hypo-hyper-d-electronic combination of transition metals, obey typical volcano plots for all the mutually compared properties along their phase diagram. The TiNi3 alloy with an average d(8)-electronic configuration creates maximal electrocatalytic activity for both hydrogen evolution and HID electrochemical separation processes, as well as maximal enthalpy of formation. At the same time the best hydridic intermetallic phases (Ti2Ni and TiNi) and alloys (between d(4) and d(5)) exhibit lower values upon each specific curve. The similarity between those properties suggests that, alike along individual transition series, there exist the same electronic configuration causes which correlate them and determine the whole electrode kinetics. (C) 2000 International Association for Hydrogen Energy. Published by Elsevier Science Ltd. All rights reserved.
T2  - International Journal of Hydrogen Energy
T1  - Electrochemical H/D isotope separation efficiencies on Ti-Ni intermetallic phases and alloys in relation to their hydridic and catalytic properties
VL  - 25
IS  - 9
SP  - 819
EP  - 823
DO  - 10.1016/S0360-3199(99)00106-8
ER  - 

@article{
author = "Stojić, Dragica Lj. and Miljanić, Šćepan S. and Grozdić, Tomislav D. and Petkovska, Ljubica T. and Jaksic, MM",
year = "2000",
abstract = "Single Ti and Ni metals, their intermetallic phases (stable and unstable) and alloys along the Ti-Ni phase diagram, have been investigated as cathode materials for separation of hydrogen isotopes (protium and deuterium, H/D) by water electrolysis from alkaline solutions. The HID separation factors obtained were compared with the hydridic features and electrocatalytic properties for the hydrogen evolution (HER), enthalpies of intermetallic formation, and in common with similar behavior of transition elements along the Periodic Table, therefrom a close correlation amongst them resulted. The Ti-Ni intermetallic phases, as hypo-hyper-d-electronic combination of transition metals, obey typical volcano plots for all the mutually compared properties along their phase diagram. The TiNi3 alloy with an average d(8)-electronic configuration creates maximal electrocatalytic activity for both hydrogen evolution and HID electrochemical separation processes, as well as maximal enthalpy of formation. At the same time the best hydridic intermetallic phases (Ti2Ni and TiNi) and alloys (between d(4) and d(5)) exhibit lower values upon each specific curve. The similarity between those properties suggests that, alike along individual transition series, there exist the same electronic configuration causes which correlate them and determine the whole electrode kinetics. (C) 2000 International Association for Hydrogen Energy. Published by Elsevier Science Ltd. All rights reserved.",
journal = "International Journal of Hydrogen Energy",
title = "Electrochemical H/D isotope separation efficiencies on Ti-Ni intermetallic phases and alloys in relation to their hydridic and catalytic properties",
volume = "25",
number = "9",
pages = "819-823",
doi = "10.1016/S0360-3199(99)00106-8"
}

Stojić, D. Lj., Miljanić, Š. S., Grozdić, T. D., Petkovska, L. T.,& Jaksic, M.. (2000). Electrochemical H/D isotope separation efficiencies on Ti-Ni intermetallic phases and alloys in relation to their hydridic and catalytic properties. in International Journal of Hydrogen Energy, 25(9), 819-823.
https://doi.org/10.1016/S0360-3199(99)00106-8

Stojić DL, Miljanić ŠS, Grozdić TD, Petkovska LT, Jaksic M. Electrochemical H/D isotope separation efficiencies on Ti-Ni intermetallic phases and alloys in relation to their hydridic and catalytic properties. in International Journal of Hydrogen Energy. 2000;25(9):819-823.
doi:10.1016/S0360-3199(99)00106-8 .

Stojić, Dragica Lj., Miljanić, Šćepan S., Grozdić, Tomislav D., Petkovska, Ljubica T., Jaksic, MM, "Electrochemical H/D isotope separation efficiencies on Ti-Ni intermetallic phases and alloys in relation to their hydridic and catalytic properties" in International Journal of Hydrogen Energy, 25, no. 9 (2000):819-823,
https://doi.org/10.1016/S0360-3199(99)00106-8 . .

TY  - JOUR
AU  - Ostojić, GM
AU  - Radak, Bojan
AU  - Petkovska, Ljubica T.
PY  - 2000
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/6291
AB  - A theoretical model of a waveguide CO2-laser was made to optimize the dimensions of the waveguide tube and resonator, i.e., to obtain the best mode structure while maximizing the output power. The results were used to design and build the laser itself around a quartz waveguide tube of 25.5 cm and 3 mm inner diameter. A simple, low-cost, and efficient VMOS based current stabilization was applied; which stabilized the current to within +/-0.5%. The working laser frequency selection and/or frequency stabilization was controlled by a piezo micro-positioner, which was coupled with an output power meter via a PC computer and driven by self-made software developed for the purpose. The experimental test of the laser showed good agreement with the model.
T2  - Journal of the Serbian Chemical Society
T1  - A frequency stabilized waveguide CO2-laser for photoacoustic spectroscopy of gases
VL  - 65
IS  - 5-6
SP  - 381
EP  - 389
UR  - https://hdl.handle.net/21.15107/rcub_vinar_6291
ER  - 

@article{
author = "Ostojić, GM and Radak, Bojan and Petkovska, Ljubica T.",
year = "2000",
abstract = "A theoretical model of a waveguide CO2-laser was made to optimize the dimensions of the waveguide tube and resonator, i.e., to obtain the best mode structure while maximizing the output power. The results were used to design and build the laser itself around a quartz waveguide tube of 25.5 cm and 3 mm inner diameter. A simple, low-cost, and efficient VMOS based current stabilization was applied; which stabilized the current to within +/-0.5%. The working laser frequency selection and/or frequency stabilization was controlled by a piezo micro-positioner, which was coupled with an output power meter via a PC computer and driven by self-made software developed for the purpose. The experimental test of the laser showed good agreement with the model.",
journal = "Journal of the Serbian Chemical Society",
title = "A frequency stabilized waveguide CO2-laser for photoacoustic spectroscopy of gases",
volume = "65",
number = "5-6",
pages = "381-389",
url = "https://hdl.handle.net/21.15107/rcub_vinar_6291"
}

Ostojić, G., Radak, B.,& Petkovska, L. T.. (2000). A frequency stabilized waveguide CO2-laser for photoacoustic spectroscopy of gases. in Journal of the Serbian Chemical Society, 65(5-6), 381-389.
https://hdl.handle.net/21.15107/rcub_vinar_6291

Ostojić G, Radak B, Petkovska LT. A frequency stabilized waveguide CO2-laser for photoacoustic spectroscopy of gases. in Journal of the Serbian Chemical Society. 2000;65(5-6):381-389.
https://hdl.handle.net/21.15107/rcub_vinar_6291 .

Ostojić, GM, Radak, Bojan, Petkovska, Ljubica T., "A frequency stabilized waveguide CO2-laser for photoacoustic spectroscopy of gases" in Journal of the Serbian Chemical Society, 65, no. 5-6 (2000):381-389,
https://hdl.handle.net/21.15107/rcub_vinar_6291 .

TY  - JOUR
AU  - Petkovska, Ljubica T.
PY  - 2000
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/2354
AB  - Carbon-dioxide spectra of some higher transitions in the 9-11 mu m region were studied. Spectra of the sequence ([10(0)1,02(0)1](I,II)-00(0)2) and hot (01(1)1-11(1)0) bands were calculated as a function of temperature. The positions of the re-vibrational transitions and their intensities were determined as a function of temperature. For lines in hot and sequence transitions whose positions are close to some of the regular lines ([10(0)0,02(0)0](I,II)-00(0)1)(1) absorption coefficients of adjacent lines were calculated as functions of line center distances and temperature. The resulting values of the absorption coefficient for conditions of constant pressure or constant volume were determined.
T2  - Spectroscopy Letters
T1  - Sequence and hot transitions in the CO2 molecule; Interference of adjacent lines belonging to different transitions as a function of temperature
VL  - 33
IS  - 3
SP  - 283
EP  - 300
DO  - 10.1080/00387010009350077
ER  - 

@article{
author = "Petkovska, Ljubica T.",
year = "2000",
abstract = "Carbon-dioxide spectra of some higher transitions in the 9-11 mu m region were studied. Spectra of the sequence ([10(0)1,02(0)1](I,II)-00(0)2) and hot (01(1)1-11(1)0) bands were calculated as a function of temperature. The positions of the re-vibrational transitions and their intensities were determined as a function of temperature. For lines in hot and sequence transitions whose positions are close to some of the regular lines ([10(0)0,02(0)0](I,II)-00(0)1)(1) absorption coefficients of adjacent lines were calculated as functions of line center distances and temperature. The resulting values of the absorption coefficient for conditions of constant pressure or constant volume were determined.",
journal = "Spectroscopy Letters",
title = "Sequence and hot transitions in the CO2 molecule; Interference of adjacent lines belonging to different transitions as a function of temperature",
volume = "33",
number = "3",
pages = "283-300",
doi = "10.1080/00387010009350077"
}

Petkovska, L. T.. (2000). Sequence and hot transitions in the CO2 molecule; Interference of adjacent lines belonging to different transitions as a function of temperature. in Spectroscopy Letters, 33(3), 283-300.
https://doi.org/10.1080/00387010009350077

Petkovska LT. Sequence and hot transitions in the CO2 molecule; Interference of adjacent lines belonging to different transitions as a function of temperature. in Spectroscopy Letters. 2000;33(3):283-300.
doi:10.1080/00387010009350077 .

Petkovska, Ljubica T., "Sequence and hot transitions in the CO2 molecule; Interference of adjacent lines belonging to different transitions as a function of temperature" in Spectroscopy Letters, 33, no. 3 (2000):283-300,
https://doi.org/10.1080/00387010009350077 . .

TY  - JOUR
AU  - Čakar, Mira M.
AU  - Vasić, Vesna M.
AU  - Petkovska, Ljubica T.
AU  - Stojić, Dragica Lj.
AU  - Avramov-Ivic, M
AU  - Milovanović, GA
PY  - 1999
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/2258
AB  - Newly synthesized oximes, mono and bis imidazole derivatives, which promise to be more effective acetylcholinesterase reactivators than standard antidotes used, were investigated by spectrophotometric and electrochemical methods. The electrochemical investigations confirmed the existence of overlapping equilibria, obtained by spectrophotometric methods. Dissociation constants of those oximes were also obtained by numerical treatment of overlapping equilibria, using the Lavendberg-Marquardt least square method, and when compared with the same for some similar compounds, were found to be very effective acetylcholinesterase reactivators. The distribution of ionic forms of the investigated oximes, as a dependence of pH values, was calculated from the obtained values of dissociation constants. The results indicated that many oxime anions will be available at physiological pH 7.4 and a relative increased ability to reactivate inhibited acetylcholinesterase could be expected. (C) 1999 Elsevier Science B.V. All rights reserved.
T2  - Journal of Pharmaceutical and Biomedical Analysis
T1  - Spectrophotometric and electrochemical study of protolytic equilibria of some oximes-acetylcholinesterase reactivators
VL  - 20
IS  - 4
SP  - 655
EP  - 662
DO  - 10.1016/S0731-7085(99)00056-4
ER  - 

@article{
author = "Čakar, Mira M. and Vasić, Vesna M. and Petkovska, Ljubica T. and Stojić, Dragica Lj. and Avramov-Ivic, M and Milovanović, GA",
year = "1999",
abstract = "Newly synthesized oximes, mono and bis imidazole derivatives, which promise to be more effective acetylcholinesterase reactivators than standard antidotes used, were investigated by spectrophotometric and electrochemical methods. The electrochemical investigations confirmed the existence of overlapping equilibria, obtained by spectrophotometric methods. Dissociation constants of those oximes were also obtained by numerical treatment of overlapping equilibria, using the Lavendberg-Marquardt least square method, and when compared with the same for some similar compounds, were found to be very effective acetylcholinesterase reactivators. The distribution of ionic forms of the investigated oximes, as a dependence of pH values, was calculated from the obtained values of dissociation constants. The results indicated that many oxime anions will be available at physiological pH 7.4 and a relative increased ability to reactivate inhibited acetylcholinesterase could be expected. (C) 1999 Elsevier Science B.V. All rights reserved.",
journal = "Journal of Pharmaceutical and Biomedical Analysis",
title = "Spectrophotometric and electrochemical study of protolytic equilibria of some oximes-acetylcholinesterase reactivators",
volume = "20",
number = "4",
pages = "655-662",
doi = "10.1016/S0731-7085(99)00056-4"
}

Čakar, M. M., Vasić, V. M., Petkovska, L. T., Stojić, D. Lj., Avramov-Ivic, M.,& Milovanović, G.. (1999). Spectrophotometric and electrochemical study of protolytic equilibria of some oximes-acetylcholinesterase reactivators. in Journal of Pharmaceutical and Biomedical Analysis, 20(4), 655-662.
https://doi.org/10.1016/S0731-7085(99)00056-4

Čakar MM, Vasić VM, Petkovska LT, Stojić DL, Avramov-Ivic M, Milovanović G. Spectrophotometric and electrochemical study of protolytic equilibria of some oximes-acetylcholinesterase reactivators. in Journal of Pharmaceutical and Biomedical Analysis. 1999;20(4):655-662.
doi:10.1016/S0731-7085(99)00056-4 .

Čakar, Mira M., Vasić, Vesna M., Petkovska, Ljubica T., Stojić, Dragica Lj., Avramov-Ivic, M, Milovanović, GA, "Spectrophotometric and electrochemical study of protolytic equilibria of some oximes-acetylcholinesterase reactivators" in Journal of Pharmaceutical and Biomedical Analysis, 20, no. 4 (1999):655-662,
https://doi.org/10.1016/S0731-7085(99)00056-4 . .

TY  - JOUR
AU  - Sovilj, Sofija P.
AU  - Vasić, Vesna M.
AU  - Stojić, Dragica Lj.
AU  - Stojčeva-Radovanović, Blaga C.
AU  - Petkovska, Ljubica T.
PY  - 1998
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/2157
AB  - The effect of the substituents, solvent polarities and hydrogen ion concentration on the electronic structure and UV/VIS absorption spectra of some Schiff bases, derivatives of N-(R-benzylidene)benzidine (R = o-NO2 and o-OH, p-OH) and N-(R-furfurylidene)benzidine (R = H and 5 - NO2), have been studied. The spectral shifts obtained in various organic solvents were discussed on the basis of the specific solute - solvent interactions through the formation of hydrogen bonds between hydrogen-bond donor (HBD) solvents and the benzidine nitrogen atom of the Schiff bases. Some interpretations of the electronic aspects of this type of hydrogen bonding were discussed as well as the stabilization effects due to the solvation. Finally, the pK values of the compounds were determined.
T2  - Spectroscopy Letters
T1  - Spectrophotometric studies of the influence of organic solvents and substituents on some Schiff bases
VL  - 31
IS  - 5
SP  - 1107
EP  - 1122
DO  - 10.1080/00387019808003288
ER  - 

@article{
author = "Sovilj, Sofija P. and Vasić, Vesna M. and Stojić, Dragica Lj. and Stojčeva-Radovanović, Blaga C. and Petkovska, Ljubica T.",
year = "1998",
abstract = "The effect of the substituents, solvent polarities and hydrogen ion concentration on the electronic structure and UV/VIS absorption spectra of some Schiff bases, derivatives of N-(R-benzylidene)benzidine (R = o-NO2 and o-OH, p-OH) and N-(R-furfurylidene)benzidine (R = H and 5 - NO2), have been studied. The spectral shifts obtained in various organic solvents were discussed on the basis of the specific solute - solvent interactions through the formation of hydrogen bonds between hydrogen-bond donor (HBD) solvents and the benzidine nitrogen atom of the Schiff bases. Some interpretations of the electronic aspects of this type of hydrogen bonding were discussed as well as the stabilization effects due to the solvation. Finally, the pK values of the compounds were determined.",
journal = "Spectroscopy Letters",
title = "Spectrophotometric studies of the influence of organic solvents and substituents on some Schiff bases",
volume = "31",
number = "5",
pages = "1107-1122",
doi = "10.1080/00387019808003288"
}

Sovilj, S. P., Vasić, V. M., Stojić, D. Lj., Stojčeva-Radovanović, B. C.,& Petkovska, L. T.. (1998). Spectrophotometric studies of the influence of organic solvents and substituents on some Schiff bases. in Spectroscopy Letters, 31(5), 1107-1122.
https://doi.org/10.1080/00387019808003288

Sovilj SP, Vasić VM, Stojić DL, Stojčeva-Radovanović BC, Petkovska LT. Spectrophotometric studies of the influence of organic solvents and substituents on some Schiff bases. in Spectroscopy Letters. 1998;31(5):1107-1122.
doi:10.1080/00387019808003288 .

Sovilj, Sofija P., Vasić, Vesna M., Stojić, Dragica Lj., Stojčeva-Radovanović, Blaga C., Petkovska, Ljubica T., "Spectrophotometric studies of the influence of organic solvents and substituents on some Schiff bases" in Spectroscopy Letters, 31, no. 5 (1998):1107-1122,
https://doi.org/10.1080/00387019808003288 . .

TY  - JOUR
AU  - Radak, Bojan
AU  - Pastirk, Igor
AU  - Ristić, Gordana
AU  - Petkovska, Ljubica T.
PY  - 1998
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/2147
AB  - Carbon dioxide laser coincidences were investigated by photoacoustic detection at laser lines 10P(28) and 9P(28) with ethene and at 10P(20) and 10P(16) with ammonia. The intensities of coincidences were measured as a function of pressure of a buffer gas (dry air) and pure gas. The intensities of two ammonia coincidences show an inversion with pressure. A method of eliminating all pressure effects other than those of spectral nature from the PA signal was introduced. This enabled deriving the pressure broadening coefficients of the coinciding absorption lines. (C) 1998 Published by Elsevier Science B.V.
T2  - Infrared Physics and Technology
T1  - Pressure effects on CO2-laser coincidences with ethene and ammonia investigated by photoacoustic detection
VL  - 39
IS  - 1
SP  - 7
EP  - 13
DO  - 10.1016/S1350-4495(97)00035-2
ER  - 

@article{
author = "Radak, Bojan and Pastirk, Igor and Ristić, Gordana and Petkovska, Ljubica T.",
year = "1998",
abstract = "Carbon dioxide laser coincidences were investigated by photoacoustic detection at laser lines 10P(28) and 9P(28) with ethene and at 10P(20) and 10P(16) with ammonia. The intensities of coincidences were measured as a function of pressure of a buffer gas (dry air) and pure gas. The intensities of two ammonia coincidences show an inversion with pressure. A method of eliminating all pressure effects other than those of spectral nature from the PA signal was introduced. This enabled deriving the pressure broadening coefficients of the coinciding absorption lines. (C) 1998 Published by Elsevier Science B.V.",
journal = "Infrared Physics and Technology",
title = "Pressure effects on CO2-laser coincidences with ethene and ammonia investigated by photoacoustic detection",
volume = "39",
number = "1",
pages = "7-13",
doi = "10.1016/S1350-4495(97)00035-2"
}

Radak, B., Pastirk, I., Ristić, G.,& Petkovska, L. T.. (1998). Pressure effects on CO2-laser coincidences with ethene and ammonia investigated by photoacoustic detection. in Infrared Physics and Technology, 39(1), 7-13.
https://doi.org/10.1016/S1350-4495(97)00035-2

Radak B, Pastirk I, Ristić G, Petkovska LT. Pressure effects on CO2-laser coincidences with ethene and ammonia investigated by photoacoustic detection. in Infrared Physics and Technology. 1998;39(1):7-13.
doi:10.1016/S1350-4495(97)00035-2 .

Radak, Bojan, Pastirk, Igor, Ristić, Gordana, Petkovska, Ljubica T., "Pressure effects on CO2-laser coincidences with ethene and ammonia investigated by photoacoustic detection" in Infrared Physics and Technology, 39, no. 1 (1998):7-13,
https://doi.org/10.1016/S1350-4495(97)00035-2 . .

TY  - JOUR
AU  - Ristić, Gordana
AU  - Petkovska, Ljubica T.
AU  - Bogdanov, Žarko
AU  - Zec, Slavica
AU  - Miljanić, Šćepan S.
PY  - 1998
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/2129
AB  - A tungsten filament, 0.12 mm in diameter, was conditioned by heating in a mixture of methane and hydrogen of three different concentration ratios. The filament was heated by an electric current. The procedure was carried out stepwise keeping either the voltage or the temperature of the filament constant. Changes in the filament material were monitored by resistance and temperature measurements. The chemical composition was checked using X-ray diffraction (XRD) analysis. The final state of the filament was investigated and photographed using the scanning-electron microscopy (SEM) technique.
T2  - Journal of the Serbian Chemical Society
T1  - Conditioning of the filament for diamond deposition by hot-filament chemical vapour deposition method
VL  - 63
IS  - 3
SP  - 231
EP  - 235
UR  - https://hdl.handle.net/21.15107/rcub_vinar_2129
ER  - 

@article{
author = "Ristić, Gordana and Petkovska, Ljubica T. and Bogdanov, Žarko and Zec, Slavica and Miljanić, Šćepan S.",
year = "1998",
abstract = "A tungsten filament, 0.12 mm in diameter, was conditioned by heating in a mixture of methane and hydrogen of three different concentration ratios. The filament was heated by an electric current. The procedure was carried out stepwise keeping either the voltage or the temperature of the filament constant. Changes in the filament material were monitored by resistance and temperature measurements. The chemical composition was checked using X-ray diffraction (XRD) analysis. The final state of the filament was investigated and photographed using the scanning-electron microscopy (SEM) technique.",
journal = "Journal of the Serbian Chemical Society",
title = "Conditioning of the filament for diamond deposition by hot-filament chemical vapour deposition method",
volume = "63",
number = "3",
pages = "231-235",
url = "https://hdl.handle.net/21.15107/rcub_vinar_2129"
}

Ristić, G., Petkovska, L. T., Bogdanov, Ž., Zec, S.,& Miljanić, Š. S.. (1998). Conditioning of the filament for diamond deposition by hot-filament chemical vapour deposition method. in Journal of the Serbian Chemical Society, 63(3), 231-235.
https://hdl.handle.net/21.15107/rcub_vinar_2129

Ristić G, Petkovska LT, Bogdanov Ž, Zec S, Miljanić ŠS. Conditioning of the filament for diamond deposition by hot-filament chemical vapour deposition method. in Journal of the Serbian Chemical Society. 1998;63(3):231-235.
https://hdl.handle.net/21.15107/rcub_vinar_2129 .

Ristić, Gordana, Petkovska, Ljubica T., Bogdanov, Žarko, Zec, Slavica, Miljanić, Šćepan S., "Conditioning of the filament for diamond deposition by hot-filament chemical vapour deposition method" in Journal of the Serbian Chemical Society, 63, no. 3 (1998):231-235,
https://hdl.handle.net/21.15107/rcub_vinar_2129 .

TY  - JOUR
AU  - Ristić, Gordana
AU  - Petkovska, Ljubica T.
AU  - Bogdanov, Žarko
AU  - Zec, Slavica
AU  - Miljanić, Šćepan S.
PY  - 1998
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/46
AB  - A tungsten filament, 0.12 mm in diameter, was conditioned by heating in a mixture of methane and hydrogen of three different concentration ratios. The filament was heated by an electric current. The procedure was carried out stepwise keeping either the voltage or the temperature of the filament constant. Changes in the filament material were monitored by resistance and temperature measurements. The chemical composition was checked using X-ray diffraction (XRD) analysis. The final state of the filament was investigated and photographed using the scanning-electron microscopy (SEM) technique.
T2  - Journal of the Serbian Chemical Society
T1  - Conditioning of the filament for diamond deposition by hot-filament chemical vapour deposition method
VL  - 63
IS  - 3
SP  - 231
EP  - 235
UR  - https://hdl.handle.net/21.15107/rcub_vinar_46
ER  - 

@article{
author = "Ristić, Gordana and Petkovska, Ljubica T. and Bogdanov, Žarko and Zec, Slavica and Miljanić, Šćepan S.",
year = "1998",
abstract = "A tungsten filament, 0.12 mm in diameter, was conditioned by heating in a mixture of methane and hydrogen of three different concentration ratios. The filament was heated by an electric current. The procedure was carried out stepwise keeping either the voltage or the temperature of the filament constant. Changes in the filament material were monitored by resistance and temperature measurements. The chemical composition was checked using X-ray diffraction (XRD) analysis. The final state of the filament was investigated and photographed using the scanning-electron microscopy (SEM) technique.",
journal = "Journal of the Serbian Chemical Society",
title = "Conditioning of the filament for diamond deposition by hot-filament chemical vapour deposition method",
volume = "63",
number = "3",
pages = "231-235",
url = "https://hdl.handle.net/21.15107/rcub_vinar_46"
}

Ristić, G., Petkovska, L. T., Bogdanov, Ž., Zec, S.,& Miljanić, Š. S.. (1998). Conditioning of the filament for diamond deposition by hot-filament chemical vapour deposition method. in Journal of the Serbian Chemical Society, 63(3), 231-235.
https://hdl.handle.net/21.15107/rcub_vinar_46

Ristić G, Petkovska LT, Bogdanov Ž, Zec S, Miljanić ŠS. Conditioning of the filament for diamond deposition by hot-filament chemical vapour deposition method. in Journal of the Serbian Chemical Society. 1998;63(3):231-235.
https://hdl.handle.net/21.15107/rcub_vinar_46 .

Ristić, Gordana, Petkovska, Ljubica T., Bogdanov, Žarko, Zec, Slavica, Miljanić, Šćepan S., "Conditioning of the filament for diamond deposition by hot-filament chemical vapour deposition method" in Journal of the Serbian Chemical Society, 63, no. 3 (1998):231-235,
https://hdl.handle.net/21.15107/rcub_vinar_46 .

TY  - JOUR
AU  - Petkovska, Ljubica T.
AU  - Miljanić, Šćepan S.
PY  - 1997
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/2096
AB  - Photoacoustic (PA) coincidence absorption spectra of ammonia and its deuterated forms with carbon-dioxide laser emission were obtained. In addition, a simple isotope synthesis procedure was developed for that purpose. The strongest coincidence for the NH, molecule was found with laser line 9R(30) at 1084.628 cm(-1). Laser PA spectra of samples with different deuterium content indicate that coincidences with laser lines 10R(14) and 10R(30) at 971.93 and 982.10 cm(-1) respectively, correspond to NH2D, while one with 10R(20) at 975.93 cm(-1) is attributed to NHD2. The data obtained are discussed in relation to their uses in isotope chemistry and analysis. They are in agreement with results published by other authors. (C) 1997 Elsevier Science B.V.
T2  - Infrared Physics and Technology
T1  - CO2-laser photoacoustic spectroscopy of deuterated ammonia
VL  - 38
IS  - 6
SP  - 331
EP  - 336
DO  - 10.1016/S1350-4495(97)00022-4
ER  - 

@article{
author = "Petkovska, Ljubica T. and Miljanić, Šćepan S.",
year = "1997",
abstract = "Photoacoustic (PA) coincidence absorption spectra of ammonia and its deuterated forms with carbon-dioxide laser emission were obtained. In addition, a simple isotope synthesis procedure was developed for that purpose. The strongest coincidence for the NH, molecule was found with laser line 9R(30) at 1084.628 cm(-1). Laser PA spectra of samples with different deuterium content indicate that coincidences with laser lines 10R(14) and 10R(30) at 971.93 and 982.10 cm(-1) respectively, correspond to NH2D, while one with 10R(20) at 975.93 cm(-1) is attributed to NHD2. The data obtained are discussed in relation to their uses in isotope chemistry and analysis. They are in agreement with results published by other authors. (C) 1997 Elsevier Science B.V.",
journal = "Infrared Physics and Technology",
title = "CO2-laser photoacoustic spectroscopy of deuterated ammonia",
volume = "38",
number = "6",
pages = "331-336",
doi = "10.1016/S1350-4495(97)00022-4"
}

Petkovska, L. T.,& Miljanić, Š. S.. (1997). CO2-laser photoacoustic spectroscopy of deuterated ammonia. in Infrared Physics and Technology, 38(6), 331-336.
https://doi.org/10.1016/S1350-4495(97)00022-4

Petkovska LT, Miljanić ŠS. CO2-laser photoacoustic spectroscopy of deuterated ammonia. in Infrared Physics and Technology. 1997;38(6):331-336.
doi:10.1016/S1350-4495(97)00022-4 .

Petkovska, Ljubica T., Miljanić, Šćepan S., "CO2-laser photoacoustic spectroscopy of deuterated ammonia" in Infrared Physics and Technology, 38, no. 6 (1997):331-336,
https://doi.org/10.1016/S1350-4495(97)00022-4 . .