TY  - GEN
A1  - Ehlert, Christopher
A1  - Holzweber, Markus
A1  - Lippitz, Andreas
A1  - Unger, Wolfgang E. S.
A1  - Saalfrank, Peter
T1  - A detailed assignment of NEXAFS resonances of imidazolium based ionic liquids
N2  - In Near Edge X-Ray Absorption Fine Structure (NEXAFS) spectroscopy X-Ray photons are used to excite tightly bound core electrons to low-lying unoccupied orbitals of the system. This technique offers insight into the electronic structure of the system as well as useful structural information. In this work, we apply NEXAFS to two kinds of imidazolium based ionic liquids ([CnC1im]+[NTf2]- and [C4C1im]+[I]-). A combination of measurements and quantum chemical calculations of C K and N K NEXAFS resonances is presented. The simulations, based on the transition potential density functional theory method (TP-DFT), reproduce all characteristic features observed by the experiment. Furthermore, a detailed assignment of resonance features to excitation centers (carbon or nitrogen atoms) leads to a consistent interpretation of the spectra.
T3  - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe - 315 
KW  - ray absorption-spectroscopy
KW  - fine-structure
KW  - spectra
KW  - simulations
KW  - molecules
KW  - dynamics
KW  - graphene
KW  - surface
KW  - salts
Y1  - 2016
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-394417
SP  - 8654
EP  - 8661
ER  - 
TY  - GEN
A1  - Frieler, Katja
A1  - Mengel, Matthias
A1  - Levermann, Anders
T1  - Delaying future sea-level rise by storing water in Antarctica
T2  - Postprints der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe
N2  - Even if greenhouse gas emissions were stopped today, sea level would continue to rise for centuries, with the long-term sea-level commitment of a 2 degrees C warmer world significantly exceeding 2 m. In view of the potential implications for coastal populations and ecosystems worldwide, we investigate, from an ice-dynamic perspective, the possibility of delaying sea-level rise by pumping ocean water onto the surface of the Antarctic ice sheet. We find that due to wave propagation ice is discharged much faster back into the ocean than would be expected from a pure advection with surface velocities. The delay time depends strongly on the distance from the coastline at which the additional mass is placed and less strongly on the rate of sea-level rise that is mitigated. A millennium-scale storage of at least 80% of the additional ice requires placing it at a distance of at least 700 km from the coastline. The pumping energy required to elevate the potential energy of ocean water to mitigate the currently observed 3 mmyr(-1) will exceed 7% of the current global primary energy supply. At the same time, the approach offers a comprehensive protection for entire coastlines particularly including regions that cannot be protected by dikes.
T3  - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe - 533 
KW  - carbon-dioxide emissions
KW  - ice-sheet
KW  - climate-change
KW  - model
KW  - collapse
KW  - commitment
KW  - Greenland
KW  - discharge
KW  - project
KW  - surface
Y1  - 2019
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-410234
SN  - 1866-8372
IS  - 533
ER  -