Aleksandr Tanichev
@imces.ru
Laboratory of ecological instrumentation
Junior researcher
EDUCATION
Tomsk State University
RESEARCH, TEACHING, or OTHER INTERESTS
Atomic and Molecular Physics, and Optics, Radiation, Chemistry, Ecology, Evolution, Behavior and Systematics
Scopus Publications
Scopus Publications
Dmitry V. Petrov and Aleksandr S. Tanichev
Elsevier BV
Aleksandr S. Tanichev, Dmitry V. Petrov, and Matvey A. Kostenko
Wiley
AbstractRaman spectroscopy is a promising method to analyze natural gas. Measurement of hydrocarbon concentrations is required for quality control of this fuel. Despite the presence of intense characteristic peaks of hydrocarbons in the range of 2800–3040 cm−1, researchers avoid this region due to the overlap with a methane spectrum. This paper presents a simple method to simulate the Raman spectrum of methane in natural gas at different pressures and concentrations of nitrogen, carbon dioxide, and ethane. A detailed description of the algorithm and the empirical parameters necessary for the simulation are provided. The method can be used to improve the accuracy of the Raman gas analysis of natural gas and other methane‐bearing media.
Aleksandr S. Tanichev and Dmitry V. Petrov
Elsevier BV
Aleksandr S. Tanichev and Dmitry V. Petrov
MDPI AG
Raman spectroscopy is a promising method for the analysis of natural gas. It is necessary to account for the broadening effects on spectral lines to improve measurement accuracy. In this study, the broadening coefficients for methane lines in the region of the ν2 band perturbed by propane, n-butane, and isobutane at room temperature were measured. We estimated the measurement errors of the concentration of oxygen and carbon dioxide in the case of neglecting the broadening effects on the methane spectrum by the pressure of C2–C6 alkanes. The obtained data are suited for the correct simulation of the methane spectrum in the hydrocarbon-bearing gases and can be used to improve the accuracy of the analysis of natural gas by Raman spectroscopy.
D. V. Petrov, I. I. Matrosov, A. S. Tanichev, M. A. Kostenko, and A. R. Zaripov
Pleiades Publishing Ltd
Dmitry V. Petrov, Ivan I. Matrosov, Alexey R. Zaripov, and Aleksandr S. Tanichev
MDPI AG
Raman spectroscopy is a promising method for analyzing natural gas due to its high measurement speed and the potential to monitor all molecular components simultaneously. This paper discusses the features of measurements of samples whose composition varies over a wide range (0.005–100%). Analysis of the concentrations obtained during three weeks of experiments showed that their variation is within the error caused by spectral noise. This result confirms that Raman gas analyzers can operate without frequent calibrations, unlike gas chromatographs. It was found that a variation in the gas composition can change the widths of the spectral lines of methane. As a result, the measurement error of oxygen concentration can reach 200 ppm. It is also shown that neglecting the measurement of pentanes and n-hexane leads to an increase in the calculated concentrations of other alkanes and to errors in the density and heating value of natural gas.
Aleksandr S. Tanichev and Dmitry V. Petrov
Wiley
AbstractThe in situ analysis of natural gas is one of the most promising applications of Raman spectroscopy. It is necessary to take into account the pressure effect on the spectrum of methane to improve the accuracy of this technique. This study aimed to develop and verify two methods for simulating the ν2 Raman band of methane at any spectral resolution and pressure. The first method was based on the use of the spectroscopic parameters of each single line (position, intensity, broadening, and shift coefficient). The second one was based on the use of the spectral profiles, each of which replaces a group of lines. The data required for the implementation of each method are presented in this work. A comparison of the calculated and measured spectra with a resolution of ~0.5 and ~7 cm−1 was performed. It was shown that the differences do not exceed 5% for each method in the range of 1–60 atm.
Aleksandr S. Tanichev and Dmitry V. Petrov
MDPI AG
In this work, the effect of nitrogen and carbon dioxide on the depolarization ratio of the ν1 band of methane in the pressure range of 0.1–5 MPa is studied. A high-sensitivity single-pass Raman spectrometer was used to obtain accurate results. Moreover, we took into account the overlap of the ν1 band by the ν3 and ν2 + ν4 bands using the simulation of their spectra. The depolarization ratio of the ν1 band in pure methane is within 0–0.001, and the effect of nitrogen and carbon dioxide on this parameter is negligible in the indicated pressure range. The obtained results are useful for correct simulation of the Raman spectrum of methane at different pressures, which is necessary to improve the accuracy of gas analysis methods using Raman spectroscopy.
A. S. Tanichev, D. V. Petrov, I. I. Matrosov, and K. K. Sharybkina
Pleiades Publishing Ltd
D. V. Petrov, I. I. Matrosov, A. R. Zaripov, A. S. Tanichev, M. A. Kostenko, and A. O. Nekhoroshev
Springer Science and Business Media LLC
Aleksandr S. Tanichev
SPIE
The study presents a method for fast modeling of the ν2 Raman band of methane at any pressure of the medium and spectral resolution of the spectrometer. For this purpose, the spectra of methane with a resolution of ~ 0.4 cm-1 in the range of 1240- 1850 cm-1 at a pressure of 1-20 atm were recorded and fitted by Voigt profiles. It was shown that the error of this method using the obtained parameters did not exceed 5% at a pressure more than 5 atm. The demonstrated algorithm can be used in fast data acquisition methods for methane-bearing media by Raman spectroscopy applications.
Dmitry V. Petrov and Aleksandr Tanichev
SPIE
The work is aimed at measuring the depolarization ratio of the ν1 Raman band of methane in nitrogen and carbon dioxide media at a pressure of 50 atm. To improve the accuracy of estimating the ν1 intensity in the depolarized spectrum, we used the simulation of the ν3 band. It was found that the environment of nitrogen and carbon dioxide has a negligible effect on the depolarization ratio of the ν1 Raman band of methane.
Matvey Kostenko, Dmitry V. Petrov, Maria Popova, and Aleksandr S. Tanichev
SPIE
This paper demonstrates the results of measuring the concentration of methane in atmospheric air using the developed laser Raman spectrometer. The integrated intensity method is used to determine concentrations from experimental spectra. Two methods of background correction near the methane peak are considered. It was found that the sensitivity limit of the spectrometer is less than 100 ppb. A comparison between measurements obtained using the presented setup and the CRDS gas analyzer showed sufficient agreement.
D. V. Petrov, I. I. Matrosov, A. R. Zaripov, and A. S. Tanichev
Springer Science and Business Media LLC
Dmitry V. Petrov, Ivan Matrosov, and Aleksandr Tanichev
SPIE
In the range of 2500–3500 cm –1 of methane Raman spectrum there are two bands (2ν4 and 2ν2) which are under Fermi resonance with an intense ν1 band. It was found that when the pressure changes from 1 to 55 atm, the peak intensity of the 2ν4 band increases by ~ 9% and peak intensity of the 2ν2 band increases by ~ 6.5% relative to the ν1 intensity. An analysis of the integrated intensities showed that in this pressure range the ratio 2ν4/ν1 increases by ~ 7%, the ratio 2ν2/ν1 (taking into account the additional contribution of the lines of the ν3 band) increases by ~ 0.7%.
Dmitry V. Petrov, Ivan I. Matrosov, Alexey R. Zaripov, Aleksandr Tanichev, and Alexey A. Kobzev
SPIE
This work is aimed to study of the ν1 band of the methane Raman spectrum in the pressure range of 1–80 atm. The wavenumber calibration was performed using the rotational–vibrational structure of the ν3 methane band. It was established, that pressure shift coefficient is about –0.02 cm–1 /atm, pressure broadening coefficient is about 0.005 cm– 1 /atm. According to the obtained experimental data, in the region of 2914–2916 cm–1 , with an increase in pressure, either the van der Waals methane complexes begin to make a noticeable contribution to the intensity of the ν1 band, or collision–induced Raman scattering increases in this range.
Yury M. Andreev, Valery A. Svetlichnyi, Alexander . Tanichev, Konstantin A. Kokh, Artem B. Kuznetsov, Gregory V. Lanskii, and Dmitry Ezhov
SPIE
We report results on comparative study of SHG in powder of promising nonlinear γ-Ga2S3 crystal. Digallium trisulfide powders with particle size from 20 μm to 500 μm were tested in comparison with powders of well-known LBO, BBO, KABO, KDP, and LN crystals under the pumping by 7 ns 1064 Nd:YAG laser. Laser-induced damage threshold of different powder fractions were determined. The γ-Ga2S3 shown high damage threshold and large SHG intensity: 56 times to that in LBO powder, 15 in BBO, 50 in KABO, 67 in KDP, and 3 in LN (for particle size: 20–50 μm), that renders it amongst the most promising crystal for frequency conversion of high-intense nanosecond radiation of near-IR lasers by optical rectification technique.