The role of halogens in both the marine boundary layer and the stratosphere has long been recognized, while their role in the free troposphere is often not considered in global chemical models. However, a careful examination of free-tropospheric chemistry constrained by observations using a full chemical data assimilation system shows that halogens do play a significant role in the free troposp...

In the earth-ocean-atmosphere system, the halogenated species take part in the cycles of several key processes involving both gas and heterogeneous interactions. The atmospheric cycles of reactive halogens are very complex specifically for those emitted from natural sources. As far as their roles in the tropospheric chemistry, the halogen compounds particularly those containing bromine (Br) and...

Alkylaminoand cycloalkylaminotriphenylphosphonium halides react with elemental halogens or interhalogen compounds to afford alkylaminoor cycloalkylaminotriphenylphosphonium trihalides. The stability of these trihalides depends on the cation as well as the trihalide anion. The assignment of a trihalide structure to these compounds was based on elemental analysis and on IRand Raman spectroscopic ...

let tx be the full transformation semigroups on the set x. for an equivalence e on x, let te(x) = {α ∈ tx : ∀(x, y) ∈ e ⇔ (xα, yα) ∈ e}it is known that te(x) is a subsemigroup of tx. in this paper, we discussthe green's *-relations, certain *-ideal and certain rees quotient semigroup for te(x).

Halogens in porewater of peat bogs – the role of peat decomposition and dissolved organic matter H. Biester, D. Selimović, S. Hemmerich, and M. Petri University of Heidelberg, Institute of Environmental Geochemistry, INF 236, 69 120 Heidelberg, Germany Zweckverband Bodensee-Wasserversorgung, Betriebsund Forschungslabor, Süßenmühle 1, 78 354 Sipplingen, Germany Received: 16 August 2005 – Accepte...

The interactions between the two CX3 groups in perhalogenated ethanes, X3C–CX3 are studied, with X3C–CX3 = H3C–CH3, F3C–CF3, F3C–CCl3, and Cl3C–CCl3. Utilising the recently developed method for revealing non-covalent interactions in molecular systems by Johnson et al. [1], a previously overlooked non-covalent interaction between halogens attached to opposite carbon atoms is unearthed. Further i...

The role of volcanogenic halogen-bearing (i.e. chlorine and bromine) compounds in stratospheric ozone chemistry and climate forcing is poorly constrained. While the 1991 eruption of Pinatubo resulted in stratospheric ozone loss, it was due to heterogeneous chemistry on volcanic sulfate aerosols involving chlorine of anthropogenic rather than volcanogenic origin, since co-erupted chlorine was sc...