Results 51 to 60 of about 2,611 (211)

Retrievals of formaldehyde from ground-based FTIR and MAX-DOAS observations at the Jungfraujoch station and comparisons with GEOS-Chem and IMAGES model simulations [PDF]

Atmospheric Measurement Techniques, 2015
As an ubiquitous product of the oxidation of many volatile organic compounds (VOCs), formaldehyde (HCHO) plays a key role as a short-lived and reactive intermediate in the atmospheric photo-oxidation pathways leading to the formation of
B. Franco, F. Hendrick, M. Van Roozendael, J.-F. Müller, T. Stavrakou, E. A. Marais, B. Bovy, W. Bader, C. Fayt, C. Hermans, B. Lejeune, G. Pinardi, C. Servais, E. Mahieu   +13 more
doaj   +1 more source

Neural Network–Assisted Metasurface Retroreflector With Wide‐Angle Adaptivity

Electron, EarlyView.
This work proposes a wide‐angle, multi‐polarization, self‐sensing, and self‐adaptive intelligent metasurface retroreflector, with a planar profile and ultrathin thickness. By integrating a pre‐trained artificial neural network (ANN), the metasurface retroreflector can recognize the incident angle and promptly adapt to changes in the incoming wave.
Jing Ning, Xunfan Wang, Kun Duan, Weixu Yang, Junming Zhao, Tian Jiang, Ke Chen, Yijun Feng   +7 more
wiley   +1 more source

Validation of OMI, GOME-2A and GOME-2B tropospheric NO₂, SO₂ and HCHO products using MAX-DOAS observations from 2011 to 2014 in Wuxi, China: investigation of the effects of priori profiles and aerosols on the satellite products [PDF]

Atmospheric Chemistry and Physics, 2017
Tropospheric vertical column densities (VCDs) of NO2, SO2 and HCHO derived from the Ozone Monitoring Instrument (OMI) on AURA and the Global Ozone Monitoring Experiment 2 aboard METOP-A (GOME-2A) and METOP-B (GOME-2B) are widely used to characterize the ...
Y. Wang, S. Beirle, J. Lampel, M. Koukouli, I. De Smedt, N. Theys, A. Li, D. Wu, P. Xie, C. Liu, M. Van Roozendael, T. Stavrakou, J.-F. Müller, T. Wagner   +13 more
doaj   +1 more source

MAX-DOAS measurements of atmospheric trace gases in Ny-Ålesund [PDF]

, 2003
Abstract. A new approach to derive tropospheric concentrations of some atmospheric trace gases from ground-based UV/vis measurements is described. The instrument, referred to as the MAX-DOAS, is based on the well-known UV/vis instruments, which use the sunlight scattered in the zenith sky as the light source and the method of Differential Optical ...
Wittrock, F., Oetjen, H., Richter, A., Fietkau, S., Medeke, T., Rozanov, A., Burrows, J. P.   +6 more
openaire   +2 more sources

Intercomparison of MAX-DOAS Vertical Profile Retrieval Algorithms: Studies using Synthetic Data [PDF]

Atmospheric Measurement Techniques, 2018
Abstract. Multi-Axis Differential Optical Absorption Spectroscopy (MAX-DOAS) is a widely used measurement technique for the detection of a variety of atmospheric trace gases. Using inverse modelling, the observation of trace gas column densities along different lines of sight enables the retrieval of aerosol and trace gas vertical profiles in the ...
U. Frieß, S. Beirle, L. Alvarado Bonilla, T. Bösch, M. M. Friedrich, F. Hendrick, A. Piters, A. Richter, M. van Roozendael, V. V. Rozanov, E. Spinei, E. Spinei, J.-L. Tirpitz, T. Vlemmix, T. Wagner, Y. Wang   +15 more
openaire   +5 more sources

D‐amino acid oxidase as a chemogenetic tool for spatiotemporally controlled hydrogen peroxide production: The oxygen connection

British Journal of Pharmacology, EarlyView.
Abstract Background and Purpose D‐amino acid oxidase (DAO) has been developed as a chemogenetic tool, to precisely manipulate redox levels in tissues and cells by generating H2O2 in the presence of D‐amino acids. The enzyme's significant oxygen consumption during H2O2 production may influence cellular oxygen levels.
Wiebke Maurer, Anke Zieseniss, Vamsi Priya Vikram, Yamin Chen, Laura Bauer, Annette Hillemann, Peter Rehling, Maithily S. Nanadikar, Diane de Zélicourt, Vartan Kurtcuoglu, Dörthe M. Katschinski   +10 more
wiley   +1 more source

Studies of the horizontal inhomogeneities in NO₂ concentrations above a shipping lane using ground-based multi-axis differential optical absorption spectroscopy (MAX-DOAS) measurements and validation with airborne imaging DOAS measurements [PDF]

Atmospheric Measurement Techniques, 2019
This study describes a novel application of an “onion-peeling” approach to multi-axis differential optical absorption spectroscopy (MAX-DOAS) measurements of shipping emissions aiming at investigating the strong horizontal inhomogeneities in NO2 over a ...
A. Seyler, A. C. Meier, F. Wittrock, L. Kattner, L. Kattner, B. Mathieu-Üffing, B. Mathieu-Üffing, B. Mathieu-Üffing, E. Peters, E. Peters, A. Richter, T. Ruhtz, A. Schönhardt, S. Schmolke, J. P. Burrows   +14 more
doaj   +1 more source

Parameterization retrieval of trace gas volume mixing ratios from airborne MAX-DOAS [PDF]

Atmospheric Measurement Techniques, 2016
Abstract. We present a parameterization retrieval of volume mixing ratios (VMR) from differential slant column density (dSCD) measurements by airborne multi-axis differential optical absorption spectroscopy (AMAX-DOAS). The method makes use of the fact that horizontally recorded limb spectra (elevation angle 0°) are strongly sensitive to the ...
B. Dix, T. K. Koenig, T. K. Koenig, R. Volkamer, R. Volkamer   +4 more
openaire   +4 more sources

Snow‐Covered Insights From Above and Below: High‐Frequency Measurement of Nitrogen Dioxide From Space and Ground

Geophysical Research Letters, Volume 53, Issue 6, 28 March 2026.
Abstract The Tropospheric Emissions: Monitoring of Pollution (TEMPO) satellite provides hourly air quality measurements over North America. This study evaluates TEMPO NO2 ${\text{NO}}_{2}$ observations over snow‐covered surfaces, highlighting its ability to capture sharp spatial and temporal gradients in NO2 ${\text{NO}}_{2}$ vertical column densities ...
D. Griffin, X. Zhao, C. McLinden, N. Yazdani, C. R. Nowlan, G. González Abad, V. Fioletov, Elisabeth Galarneau, Cris Mihele, Sumi Wren, Yushan Su, Lukas Fehr, Adam Bourassa   +12 more
wiley   +1 more source

Enhancing MAX-DOAS atmospheric remote sensing by multispectral polarimetry

, 2021
Multi-AXis Differential Optical Absorption Spectroscopy (MAX-DOAS) is a well-established remote sensing technique for the detection of atmospheric aerosol and trace gases. Ultra-violet and visible radiation spectra of skylight are analysed to obtain information on different atmospheric parameters.
openaire   +2 more sources