Decontamination of chemical warfare agents using perchloroethylene-Marlowet IHF-H2O-based microemulsions: wetting and extraction properties on realistic surfaces

Wellert S, Imhof H, Dolle M, Altmann H-J, Richardt A, Hellweg T. Decontamination of chemical warfare agents using perchloroethylene-Marlowet IHF-H2O-based microemulsions: wetting and extraction properties on realistic surfaces. Colloid & Polymer Science. 2008;286(4):417-426.At the present time, considerable efforts are being made to develop new media for the decontamination of a variety of toxic compounds. In the present contribution, new microemulsions with promising properties are presented. Moreover, the decontamination of surfaces, with an emphasis on varnished metal surfaces of exterior and interior equipment, is investigated using these microemulsions. Studies of the phase behavior of the system water-perchloroethylene-IHF-2-propanol are reported and the microemulsion phases are recognized. The wetting behavior on contaminated surfaces and the extraction capabilities with respect to contaminants are essential for an efficient decontamination. Hence, suitable microemulsions are identified on the basis of these properties. The decontamination efficiency of these microemulsions is first estimated on the basis of the ability to wet typical chemical nonresistant varnished steel sheets, which are authentic model systems for real surfaces. Afterwards, promising microemulsions and, as reference, different solvents are tested with respect to their capability to solubilize sulfur-mustard agent, again using realistic surfaces contaminated with this chemical warfare agent. Several microemulsions are found, which have the desired properties

Macrofossil floras of the Latady Basin, Antarctic Peninsula

New collections of plant material from the Merrick and Sweeney Mountains provide further evidence of Jurassic floral diversity in the Antarctic Peninsula. Eighteen taxa are recognised, including sphenophytes (Equisetum), ferns (Cladophlebis, Sphenopteris, Coniopteris), Bennettitales (Otozamites, Zamites, Ptilophyllum, Dicytozamites, Williamsonia), conifers (Pagiophyllum, Brachyphyllum, Elatocladus), and other seed plants (Taeniopteris, Archangelskya, Pachypteris). Many of these species occur in floras from the Botany Bay Group (Early–Middle Jurassic), and other Late Jurassic to Early Cretaceous sites across the Antarctic Peninsula. The plant material from the Latady Basin occurs in two main associations with distinct floristic compositions that reflect local environmental and taphonomic conditions. The richest localities occur in the deltaic settings, where paleosoil and leaf litter layers are preserved. In contrast, relatively little plant material is found in the wholly marine units such as those from the Hauberg Mountains