The characterization of historical mortars was performed by thermal analysis (TG-DTG), simultaneo... more The characterization of historical mortars was performed by thermal analysis (TG-DTG), simultaneous infrared spectroscopy (TG-FTIR) and inductively coupled plasma atomic emission spectrometry (ICP-AES). The samples were taken from St. John Church (Tartu, ...
Proceedings of The Estonian Academy of Sciences, 2008
Landfill disposal is the onl y reasonable option for cyclone ash due to its elev ated concentrati... more Landfill disposal is the onl y reasonable option for cyclone ash due to its elev ated concentrations of the heavy metals Cd (25 mg kg-1; d.w.), Zn (3630 mg kg-1; d.w.), Ba (4260 mg kg-1; d.w.), and Hg (1.7 mg kg-1; d.w.). The distribution of heavy metals (i.e. Cd, Cu, Pb, Cr, Zn, As, V, and Ba) after a three-stage
The spectrochemical and thermal analysis of different archaeological samples as bricks, terra-cot... more The spectrochemical and thermal analysis of different archaeological samples as bricks, terra-cotta and local clays were carried out. The concentration of major and minor elements of samples was determined by sequential inductively coupled plasma atomic emission spectrometry. The method was tested by determining Si, Al, Fe, Ca, Mg, Mn, Pb, Cu, Zn, Ti, Na and K in the standard solutions and reference material GXR-4. The precision of the determination (relative standard deviation) ranged from 0.4 to 1.54%. The clay minerals are the main materials for the production of bricks and terra-cotta figures. Thermogravimetric (TG) and differential (TG-DTG) analysis and Fourier transform infrared spectrometry (FTIR) methods can be used for the study of characteristic reactions, associated with the course of the heating. The TG-DTG curves were obtained in the temperature range 25-900 degrees C, and the dynamic experiment was carried out in the air and nitrogen atmosphere. The infrared evolved gas analysis was performed using FTIR in the dynamic nitrogen atmosphere.
A case study of ISO GUM-based estimation of measurement uncertainty of quantitative surface eleme... more A case study of ISO GUM-based estimation of measurement uncertainty of quantitative surface elemental analysis is presented. The analytical task was the measurement of iron content in the ink writing on the surface of an 18 th century manuscript by electron probe microanalysis using a scanning electron microscope equipped with an energy-dispersive Xray spectrometer (SEM=EDS). The problems that arise in uncertainty estimation of quantitative surface analysis are outlined (defining the measurand, preparing calibration standards, non-uniformity of the surface, etc) and ways of overcoming them are suggested. The average iron content on the ink-covered surface of the sample manuscript was found to be 0.12 AE 0.04 mg mm À2 (at confidence level 95.5%). Paper sheets with ink lines of known iron contents were used as calibration standards. The main source of uncertainty was the variability of the parallel measurement results from different locations of the sample surface (mostly due to the variations in the surface structure of paper), which contributed 78% of the total uncertainty. It is concluded that EPMA using a SEM=EDS is suitable for at least semi-quantitative determination of iron in the writing of ink-written manuscripts. Several specific issues in uncertainty analysis are pointed out that need further investigation.
The trace element analysis of superconductor oxides YBa 2 Cu 3 O 72x was performed by use of a PU... more The trace element analysis of superconductor oxides YBa 2 Cu 3 O 72x was performed by use of a PU 7000 sequential inductively coupled plasma atomic emission spectrometer (ICP-AES). The manganese emission line at 259.373 nm was used to ®nd the optimum viewing position in the plasma for the determination of Ca, Mg, Fe, Mn, Al, Ni, Si and Sr. The different emission lines were compared and matrix effects of major elements (Cu, Ba and Y) were studied. A scan of emission lines Mn II at 259.373 nm, Mg II at 280.270 nm, Fe II at 259.940 nm, Al I at 309.271, Ni II at 221.647 nm, Ca II at 396.847 nm, Si I at 251.611 nm and Sr II at 407.771 nm was performed. The detection limits (DL) of the elements were in the range 0.002±0.006 mg l 21 and the practical detection limits (PDL) were between 2.0610 25 and 1.2610 -4 (% m/m). The precision of the determination (RSD) ranged from 1.4 to 3.2% and was dependent on the element and its concentration.
Abstract UVVis spectrophotometric (UVVis) and flame atomic absorption spectrometric (FAAS) anal... more Abstract UVVis spectrophotometric (UVVis) and flame atomic absorption spectrometric (FAAS) analysis for iron determination in a pharmaceutical product were compared in terms of uncertainty budgets. Both methods are selective for iron; no interference due to other ...
The elemental composition of superconductor oxides YBa2Cu308_x were determined by inductively cou... more The elemental composition of superconductor oxides YBa2Cu308_x were determined by inductively coupled plasma atomic emission spectrometry (ICP-AES) and complexometric titration. Samples were dissolved in dilute HCl. A sequential PU 7000 Philips inductively coupled plasma atomic emission spectrometer was used for the measurements. A comparison of the different atom and ion emission lines of yttrium, barium and copper was carried out. The effect of changes of forward radio frequency (RF) power coupled into the plasma on emission intensity of various spectral lines was studied. The RF power was changed from 0.8 to 1.2 kW. The changes in the net intensities (%) of the emission lines of Cu(1) at 324.754 nm, Cu(I1) at 224.7OOnm. Ba(I1) at 455.403, Ba(II) at 493.409nm, Y(I1) at 371.030nm and Y(II) at 360.073nm were calculated. The indicator 1-(2-Pyridylazo)-2-Naphthol (PAN) and different buffers were used for the complexometric titration of Cu, Y and Ba. No statistically significant differences were found between the results of ICP-AES and chemical methods of analysis.
The characterisation of rare earth elements carbonates (REECs) was performed by thermal analysis ... more The characterisation of rare earth elements carbonates (REECs) was performed by thermal analysis (TG-DTG) combined with simultaneous infrared evolved gas analysis-Fourier transform infrared (EGA-FTIR) spectroscopy. The TG-DTG curves were obtained using the Perkin-Elmer PC series TGA-7 thermogravimetric analyser in the temperature range 25-800 • C both in dynamic air and nitrogen atmosphere.
The characterization of historical mortars was performed by thermal analysis (TG-DTG), simultaneo... more The characterization of historical mortars was performed by thermal analysis (TG-DTG), simultaneous infrared spectroscopy (TG-FTIR) and inductively coupled plasma atomic emission spectrometry (ICP-AES). The samples were taken from St. John Church (Tartu, ...
Proceedings of The Estonian Academy of Sciences, 2008
Landfill disposal is the onl y reasonable option for cyclone ash due to its elev ated concentrati... more Landfill disposal is the onl y reasonable option for cyclone ash due to its elev ated concentrations of the heavy metals Cd (25 mg kg-1; d.w.), Zn (3630 mg kg-1; d.w.), Ba (4260 mg kg-1; d.w.), and Hg (1.7 mg kg-1; d.w.). The distribution of heavy metals (i.e. Cd, Cu, Pb, Cr, Zn, As, V, and Ba) after a three-stage
The spectrochemical and thermal analysis of different archaeological samples as bricks, terra-cot... more The spectrochemical and thermal analysis of different archaeological samples as bricks, terra-cotta and local clays were carried out. The concentration of major and minor elements of samples was determined by sequential inductively coupled plasma atomic emission spectrometry. The method was tested by determining Si, Al, Fe, Ca, Mg, Mn, Pb, Cu, Zn, Ti, Na and K in the standard solutions and reference material GXR-4. The precision of the determination (relative standard deviation) ranged from 0.4 to 1.54%. The clay minerals are the main materials for the production of bricks and terra-cotta figures. Thermogravimetric (TG) and differential (TG-DTG) analysis and Fourier transform infrared spectrometry (FTIR) methods can be used for the study of characteristic reactions, associated with the course of the heating. The TG-DTG curves were obtained in the temperature range 25-900 degrees C, and the dynamic experiment was carried out in the air and nitrogen atmosphere. The infrared evolved gas analysis was performed using FTIR in the dynamic nitrogen atmosphere.
A case study of ISO GUM-based estimation of measurement uncertainty of quantitative surface eleme... more A case study of ISO GUM-based estimation of measurement uncertainty of quantitative surface elemental analysis is presented. The analytical task was the measurement of iron content in the ink writing on the surface of an 18 th century manuscript by electron probe microanalysis using a scanning electron microscope equipped with an energy-dispersive Xray spectrometer (SEM=EDS). The problems that arise in uncertainty estimation of quantitative surface analysis are outlined (defining the measurand, preparing calibration standards, non-uniformity of the surface, etc) and ways of overcoming them are suggested. The average iron content on the ink-covered surface of the sample manuscript was found to be 0.12 AE 0.04 mg mm À2 (at confidence level 95.5%). Paper sheets with ink lines of known iron contents were used as calibration standards. The main source of uncertainty was the variability of the parallel measurement results from different locations of the sample surface (mostly due to the variations in the surface structure of paper), which contributed 78% of the total uncertainty. It is concluded that EPMA using a SEM=EDS is suitable for at least semi-quantitative determination of iron in the writing of ink-written manuscripts. Several specific issues in uncertainty analysis are pointed out that need further investigation.
The trace element analysis of superconductor oxides YBa 2 Cu 3 O 72x was performed by use of a PU... more The trace element analysis of superconductor oxides YBa 2 Cu 3 O 72x was performed by use of a PU 7000 sequential inductively coupled plasma atomic emission spectrometer (ICP-AES). The manganese emission line at 259.373 nm was used to ®nd the optimum viewing position in the plasma for the determination of Ca, Mg, Fe, Mn, Al, Ni, Si and Sr. The different emission lines were compared and matrix effects of major elements (Cu, Ba and Y) were studied. A scan of emission lines Mn II at 259.373 nm, Mg II at 280.270 nm, Fe II at 259.940 nm, Al I at 309.271, Ni II at 221.647 nm, Ca II at 396.847 nm, Si I at 251.611 nm and Sr II at 407.771 nm was performed. The detection limits (DL) of the elements were in the range 0.002±0.006 mg l 21 and the practical detection limits (PDL) were between 2.0610 25 and 1.2610 -4 (% m/m). The precision of the determination (RSD) ranged from 1.4 to 3.2% and was dependent on the element and its concentration.
Abstract UVVis spectrophotometric (UVVis) and flame atomic absorption spectrometric (FAAS) anal... more Abstract UVVis spectrophotometric (UVVis) and flame atomic absorption spectrometric (FAAS) analysis for iron determination in a pharmaceutical product were compared in terms of uncertainty budgets. Both methods are selective for iron; no interference due to other ...
The elemental composition of superconductor oxides YBa2Cu308_x were determined by inductively cou... more The elemental composition of superconductor oxides YBa2Cu308_x were determined by inductively coupled plasma atomic emission spectrometry (ICP-AES) and complexometric titration. Samples were dissolved in dilute HCl. A sequential PU 7000 Philips inductively coupled plasma atomic emission spectrometer was used for the measurements. A comparison of the different atom and ion emission lines of yttrium, barium and copper was carried out. The effect of changes of forward radio frequency (RF) power coupled into the plasma on emission intensity of various spectral lines was studied. The RF power was changed from 0.8 to 1.2 kW. The changes in the net intensities (%) of the emission lines of Cu(1) at 324.754 nm, Cu(I1) at 224.7OOnm. Ba(I1) at 455.403, Ba(II) at 493.409nm, Y(I1) at 371.030nm and Y(II) at 360.073nm were calculated. The indicator 1-(2-Pyridylazo)-2-Naphthol (PAN) and different buffers were used for the complexometric titration of Cu, Y and Ba. No statistically significant differences were found between the results of ICP-AES and chemical methods of analysis.
The characterisation of rare earth elements carbonates (REECs) was performed by thermal analysis ... more The characterisation of rare earth elements carbonates (REECs) was performed by thermal analysis (TG-DTG) combined with simultaneous infrared evolved gas analysis-Fourier transform infrared (EGA-FTIR) spectroscopy. The TG-DTG curves were obtained using the Perkin-Elmer PC series TGA-7 thermogravimetric analyser in the temperature range 25-800 • C both in dynamic air and nitrogen atmosphere.
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