Heterogeneous Chemistry of Nitryl Halides in Relation to Tropospheric Halogen Activation   总被引：1，自引：0，他引：1  

F. Schweitzer  Ph. Mirabel  Ch. George 《Journal of Atmospheric Chemistry》1999,34(1):101-117

The heterogeneous chemistry of nitryl chloride and nitryl bromide by salt containing solutions was studied as a function of temperature in the range from 275 to 293 K with the wetted-wall flowtube combined with FTIR and mass spectrometry detection. Uptake coefficients and values of the product Hk^1/2 on these saline solutions have been determined. For nitryl halides interacting with NaI and NaBr solutions, the values of the product Hk^1/2 are respectively 4384.7±326.7 and 103.1±18.7 M atm^-1 s^-1/2 for nitryl chloride at 275 K and 544.2±94.7 and 47.7±15.2 M atm^-1 s^-1/2 for nitryl bromide at 278 K. When reacting with NaI or NaBr solutions, these heterogeneous reactions release, as major products, the molecular forms of the halogen i.e., respectively I₂ and Br₂. A simplified reaction scheme explaining the formation of these products is presented and is inserted into a model simulating the chemistry in the marine boundary layer. The modelling effort showed Cl and BrO atoms concentrations up to 5×10⁴ and 1.8×10⁶ molecules cm^-3 respectively, which are comparable to values actually measured in field campaigns.  相似文献   

Deep infrared imaging and spectroscopy of the nearby late M‐dwarf DENIS‐P J104814 –395606     

R. Neuhuser  E.W. Guenther  J. Alves  N. Grosso  Ch. Leinert  Th. Ratzka  Th. Ott  M. Mugrauer  F. Comern  A. Eckart  W. Brandner 《Astronomische Nachrichten》2002,323(5):447-452

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Book reviews: Black Hole Gravitohydrodynamics. By Brian Punsley     

Ch. Fendt 《Astronomische Nachrichten》2003,324(5):507-508

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The sulfur species in hot rocky exoplanet atmospheres     

L. J. Janssen  P. Woitke  O. Herbort  M. Min  K. L. Chubb  Ch. Helling  L. Carone 《Astronomische Nachrichten》2023,344(10):e20230075

The first JWST observations of hot Jupiters showed an unexpected detection of SO ${}_2$ in their hydrogen-rich atmospheres. We investigate how much sulfur can be expected in the atmospheres of rocky exoplanets and which sulfur molecules can be expected to be most abundant and detectable by transmission spectroscopy. We run thermochemical equilibrium models at the crust–atmosphere interface, considering surface temperatures 500–5000 K, surface pressures 1–100 bar, and various sets of element abundances based on common rock compositions. Between 1000 and 2000 K, we find gaseous sulfur concentrations of up to 25% above the rock in our models. SO ${}_2$, SO, H ${}_2$S, and S ${}_2$ are by far the most abundant sulfur molecules. SO ${}_2$ shows potentially detectable features in transmission spectra at about 4 $\mu$m, between 7 and 8 $\mu$m, and beyond 15 $\mu$m. In contrast, the sometimes abundant H ${}_2$S molecule is difficult to detect in these spectra, which are mostly dominated by H ${}_2$O and CO ${}_2$. Although the molecule PS only occurs with concentrations ppm, it can cause a strong absorption feature between 0.3 and 0.65 $\mu$m in some of our models for high surface pressures. The detection of sulfur molecules would enable a better characterization of the planetary surface.  相似文献