Large perturbations of ammonium and organic acids content in the Summit-Greenland ice core. Fingerprint from forest fires?

Biomass burning is influencing the atmospheric chemistry by emitting large amounts of reactive species such as hydrocarbons, organic acids and nitrogen compounds [Andreae et al., 1988]. Polar ice cores provide a unique record of precipitation whose chemistry reflects the atmospheric composition at the time of deposition. The analysis of such ice samples therefore allows an estimate to be made of the concentration of atmospheric impurities in the past. During the first season of the deep drill operation (GRIP) at Summit, Central Greenland (72° 34' N, 37° 38'W) continuous ammonium (NH4+) measurements were performed between 100 and 600 m depth covering the time period from 330 to 2500 years B.P. The NH4+ concentrations show seasonal variations between 1–20 ng.g−1 with some sporadic high values up to 600 ng.g−1 in narrow layers. The chemical fingerprint points to biomass burning causing the high ammonium peaks

A Mesh Adaptation Strategy to Predict Pressure Losses in LES of Swirled Flows

The research leading to these results has received funding from the European Research Council under the European Union’s Seventh Framework Program (FP/2007-2013) / ERC Grant Agreement ERC-AdG 319067-INTECOCIS

Je schneller desto besser? - Zeit im Management

Obwohl in der Ökonomik relativ wenig thematisiert, ist die «Zeit» für den ökonomischen Erfolg in der heutigen Wirtschaft von entscheidender Bedeutung. Der Schnellere gewinnt den Wettbewerb, nicht der Grössere. Produktiver ist, wer weniger Zeit braucht, und rationalisieren heisst Zeit sparen: Je mehr man gleichzeitig tun kann, desto besser! Wer die Kontrolle über die Zeit hat, hat das Sagen. Im alten Ägypten waren das die Astronomen. Wie wird Zeit in heutigen Organisationen kontrolliert ? Dazu werden zwei System- und zwei Personenprobleme sowie zwei Empfehlungen skizziert