THAIS CORREA
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Artigo IPEN-doc 28401 Methane detection in the lower troposphere related to the burning of biomass and leakage in a petrochemical pole, using Raman lidar technique2021 - MACEDO, FERNANDA de M.; CORREA, THAIS; ARAUJO, ELAINE C.; ANDRADE, IZABEL da S.; GUARDANI, ROBERTO; VESELOVSKII, IGOR; LANDULFO, EDUARDOFugitive emissions, defined as unintended or irregular leaks of gases and vapors, are an important source of pollutants to the atmosphere, which is difficult to monitor and control. These sources are present in different sites, especially in regions that are growing in size and economic activity. In this study, we present the results of the capability to detect methane profiles at low troposphere combining data retrieval correlations between a rotacional/vibracional Raman lidar (RVRL) and a cavity ring-down spectrometer (CRDS). The measurements were made at two different sites, metropolitan area of São Paulo (MSP) and industrial area of Cubatão (IC). The lidar is based on a tripled Nd:YAG laser with a 20 Hz repetition rate, operating on the 355 nm wavelength elastic channel, the 353 nm and 396 nm wavelength inelastic channels. A measurement protocol was established, considering acquisition time for signal accumulation, climatic conditions and data above and below the planetary boundary layer. The idea was to establish specific measurement procedures for situations related to product leakage in the oil process and natural events, such as biomass burning. With over 150 hours of data acquisition, the results pointed the possibility of analyzing data from distances up to 1500 m with an initial resolution of 7.5 m which was extended to 100 - 300 m after data smoothing for obtaining final results. The concentration was calculated from the ratio between the methane Raman backscatter signal and the nitrogen signal, at 396 nm and 353 nm, respectively. The temporal variation of methane concentrations was correlated with CRDS data, in order to obtain a first degree calibration.Artigo IPEN-doc 27050 Correlation study between air quality data and the Lidar system in Cubatao, Sao Paulo2017 - ARAUJO, ELAINE C.; ANDRADE, IZABEL da S.; MACEDO, FERNANDA de M.; CORREA, THAIS; SALANI, MARIA H.G. de A.; COSTA, RENATA F. da; RAMOS, SERGIANA dos P.; MARQUES, MARCIA T.A.; LOPES, DANIEL S.; GUARDANI, MARIA L.G.; LANDULFO, EDUARDO; GUARDANI, ROBERTOWe present here the results of two methods with a scanning multiwavelength elastic lidar system and Beta Ray method (CETESB) realized in an industrial area. The objective is a comparer of these two methods to identify fixed sources of aerosol and to monitor plume dispersion. The results of the two aligned techniques indicate that can provide information on the concentration, spatial and temporal distribution of aerosol.Artigo IPEN-doc 26790 Correlation between two different real time data acquisition systems2019 - MACEDO, FERNANDA M.; CORREA, THAIS; ARAUJO, ELAINE; ANDRADE, IZABEL; ARLEQUES, ANTONIO G.; MIRANDA, JULIANA T. de M.; SILVA, JONATAN da; GUARDANI, ROBERTO; VESELOVSKII, IGOR; LANDULFO, EDUARDOFugitive emissions, defined as unintended or irregular leaks of gases and vapors, these are an important source of pollutants to the atmosphere, which is difficult to monitor and control. These sources are present in different sites, including megacities like São Paulo that are growing in size and economic activity. At the same time, there is a remarkable growth in concerns about the environmental issues associated with these activities. In a constantly changing world, with increasing concentrations of greenhouse gases (GHGs), among them methane (CH4) and volatile organic compounds (VOC), mitigation of atmospheric emission of these gases to contain global warming, make field campaigns in the metropolitan region of São Paulo very relevant. Optical remote sensing techniques as lidar can attend the need for real time and trustable information on fugitive emissions. The Cavity Ringdown Laser Spectroscopy (CRDS) technique was adopted because it is widely used in the detection of gas samples that absorb light at specific wavelengths and also for their ability to detect mole fractions up to the parts per trillion level. The Raman lidar system used includes a commercial laser pulsed Nd:YAG Quantel S.A., model CFR 200, with wavelengths of 355 nm, 353 nm and 396 nm, 120 mJ pulse power, with laser repetition rate of 20 Hz and pulse width of 20 s, with a spatial resolution of 7,5 m. The system includes an ethernet interface, used together with LabView software to control the measurement and readout of the acquired data. The mixing ratio of CH4 can be observed within the planetary boundary layer. The measured methane profiles correlate with the acquisitions made with the CRDS, however, an additional contribution of control data in which the Raman lines detect with high sensitivity.Artigo IPEN-doc 24723 Monitoring the industrial sources of aerosol in Cubatao, Brazil, using a scanning elastic lidar and a lidar doppler2018 - COSTA, RENATA F. da; MARQUES, MARCIA T.A.; MACEDO, FERNANDA de M.; ANDRADE, IZABEL da S.; ARAUJO, ELAINE C.; CORREA, THAIS; SALANI, MARIA H.G. de A.; LOPES, DANIEL S.; GUARDANI, MARIA L.G.; LANDULFO, EDUARDO; GUARDANI, ROBERTOField campaigns with a scanning multiwavelength elastic lidar coupled with a Doppler system to monitor industrial atmospheric aerosol emissions were carried out, with the objective of monitoring aerosol emission sources and plume dispersion. Since the technique provides information on the spatial and temporal distribution of aerosol concentration, the implementation of a systematic monitoring procedure is proposed as a valuable tool in air quality monitoring applied to regions of interest.