@article{SkrabaniaLaschewskyvonBerlepschetal.2009, author = {Skrabania, Katja and Laschewsky, Andr{\´e} and von Berlepsch, Hans and Boettcher, Christoph}, title = {Synthesis and micellar self-assembly of ternary hydrophilic-lipophilic-fluorophilic block copolymers with a linear PEO chain}, issn = {0743-7463}, doi = {10.1021/La900253j}, year = {2009}, abstract = {Linear amphiphilic diblock and ternary triblock copolymers were synthesized by the RAFT method in two successive steps using a poly(ethylene oxide) (PEO) macrochain transfer agent, butyl or 2-ethylhexyl acrylate, and 1H, 1H, 2H, 2H-perfluorodecyl acrylate. The diblock and the triblock copolymers, which consist of a hydrophilic, a lipophilic, and a short fluorophilic block, self-assemble in water into spherical micellar aggregates. Imaging by cryogenic transmission electron microscopy (cryo-TEM) revealed that the micellar cores of the aggregates made from these "triphilic" copolymers can undergo local phase separation to form a unique ultrastructure. In these multicompartment micelles, it appears that extended nonspherical domains, presumably made of nanocrystallites of the fluorocarbon block, are embedded in the hydrocarbon matrix forming the spherical micellar core. This novel internal structure of a micellar core is attributed to the mutual incompatibility of the fluorocarbon and hydrocarbon side chains in combination with the tendency of the used fluorocarbon acrylate monomer to undergo side-chain crystallization.}, language = {en} } @article{vonBerlepschBoettcherSkrabaniaetal.2009, author = {von Berlepsch, Hans and Boettcher, Christoph and Skrabania, Katja and Laschewsky, Andr{\´e}}, title = {Complex domain architecture of multicompartment micelles from a linear ABC triblock copolymer revealed by cryogenic electron tomography}, issn = {1359-7345}, doi = {10.1039/B903658j}, year = {2009}, abstract = {Cryo-electron tomography of raspberry-like multicompartment micelles formed by a linear ABC triblock copolymer in water revealed that the fluorocarbon domains may be dispersed all over the hydrocarbon core.}, language = {en} } @article{MarsatHeydenreichKleinpeteretal.2011, author = {Marsat, Jean-Noel and Heydenreich, Matthias and Kleinpeter, Erich and Berlepsch, Hans V. and Boettcher, Christoph and Laschewsky, Andr{\´e}}, title = {Self-Assembly into multicompartment micelles and selective solubilization by Hydrophilic-Lipophilic-Fluorophilic block copolymers}, series = {Macromolecules : a publication of the American Chemical Society}, volume = {44}, journal = {Macromolecules : a publication of the American Chemical Society}, number = {7}, publisher = {American Chemical Society}, address = {Washington}, issn = {0024-9297}, doi = {10.1021/ma200032j}, pages = {2092 -- 2105}, year = {2011}, abstract = {Amphiphilic linear ternary block copolymers (ABC) were synthesized in three consecutive steps by the reversible addition fragmentation chain transfer (RAFT) method. Using oligo(ethylene oxide) monomethyl ether acrylate, benzyl acrylate, and 1H,1H-perfluorobutyl acrylate monomers, the triblock copolymers consist of a hydrophilic (A), a lipophilic (B), and a fluorophilic (C) block. The block sequence of the triphilic copolymers was varied systematically to provide all possible variations: ABC, ACB, and BAC. All blocks have glass transition temperatures below 0 degrees C. Self-assembly into spherical micellar aggregates was observed in aqueous solution, where hydrophobic cores undergo local phase separation into various ultrastructures as shown by cryogenic transmission electron microscopy (cryo-TEM). Selective solubilization of substantial quantities of hydrocarbon and fluorocarbon low molar mass compounds by the lipophilic and fluorophilic block, respectively, is demonstrated.}, language = {en} } @article{KuckeinDierckeGonzalezManriqueetal.2017, author = {Kuckein, Christoph and Diercke, Andrea and Gonz{\´a}lez Manrique, Sergio Javier and Verma, Meetu and Loehner-Boettcher, Johannes and Socas-Navarro, H. and Balthasar, Horst and Sobotka, M. and Denker, Carsten}, title = {Ca II 8542 angstrom brightenings induced by a solar microflare}, series = {Astronomy and astrophysics : an international weekly journal}, volume = {608}, journal = {Astronomy and astrophysics : an international weekly journal}, publisher = {EDP Sciences}, address = {Les Ulis}, issn = {1432-0746}, doi = {10.1051/0004-6361/201731319}, pages = {13}, year = {2017}, abstract = {Aims. We study small-scale brightenings in Ca II 8542 angstrom line-core images to determine their nature and effect on localized heating and mass transfer in active regions. Methods. High-resolution two-dimensional spectroscopic observations of a solar active region in the near-infrared Ca II 8542 angstrom line were acquired with the GREGOR Fabry-Perot Interferometer attached to the 1.5-m GREGOR telescope. Inversions of the spectra were carried out using the NICOLE code to infer temperatures and line-of-sight (LOS) velocities. Response functions of the Ca II line were computed for temperature and LOS velocity variations. Filtergrams of the Atmospheric Imaging Assembly (AIA) and magnetograms of the Helioseismic and Magnetic Imager (HMI) were coaligned to match the ground-based observations and to follow the Ca II brightenings along all available layers of the atmosphere. Results. We identified three brightenings of sizes up to 2 ' x 2 ' that appeared in the Ca II 8542 angstrom line-core images. Their lifetimes were at least 1.5 min. We found evidence that the brightenings belonged to the footpoints of a microflare (MF). The properties of the observed brightenings disqualified the scenarios of Ellerman bombs or Interface Region Imaging Spectrograph (IRIS) bombs. However, this MF shared some common properties with flaring active-region fibrils or flaring arch filaments (FAFs): (1) FAFs and MFs are both apparent in chromospheric and coronal layers according to the AIA channels; and (2) both show flaring arches with lifetimes of about 3.0-3.5 min and lengths of similar to 20 ' next to the brightenings. The inversions revealed heating by 600 K at the footpoint location in the ambient chromosphere during the impulsive phase. Connecting the footpoints, a dark filamentary structure appeared in the Ca II line-core images. Before the start of the MF, the spectra of this structure already indicated average blueshifts, meaning upward motions of the plasma along the LOS. During the impulsive phase, these velocities increased up to -2.2 km s(-1). The structure did not disappear during the observations. Downflows dominated at the footpoints. However, in the upper photosphere, slight upflows occurred during the impulsive phase. Hence, bidirectional flows are present in the footpoints of the MF.}, language = {en} } @article{HeinrichBalanzateguiBensetal.2018, author = {Heinrich, Ingo and Balanzategui, Daniel and Bens, Oliver and Blasch, Gerald and Blume, Theresa and Boettcher, Falk and Borg, Erik and Brademann, Brian and Brauer, Achim and Conrad, Christopher and Dietze, Elisabeth and Dr{\"a}ger, Nadine and Fiener, Peter and Gerke, Horst H. and G{\"u}ntner, Andreas and Heine, Iris and Helle, Gerhard and Herbrich, Marcus and Harfenmeister, Katharina and Heussner, Karl-Uwe and Hohmann, Christian and Itzerott, Sibylle and Jurasinski, Gerald and Kaiser, Knut and Kappler, Christoph and Koebsch, Franziska and Liebner, Susanne and Lischeid, Gunnar and Merz, Bruno and Missling, Klaus Dieter and Morgner, Markus and Pinkerneil, Sylvia and Plessen, Birgit and Raab, Thomas and Ruhtz, Thomas and Sachs, Torsten and Sommer, Michael and Spengler, Daniel and Stender, Vivien and St{\"u}ve, Peter and Wilken, Florian}, title = {Interdisciplinary Geo-ecological Research across Time Scales in the Northeast German Lowland Observatory (TERENO-NE)}, series = {Vadose zone journal}, volume = {17}, journal = {Vadose zone journal}, number = {1}, publisher = {Soil Science Society of America}, address = {Madison}, issn = {1539-1663}, doi = {10.2136/vzj2018.06.0116}, pages = {25}, year = {2018}, abstract = {The Northeast German Lowland Observatory (TERENO-NE) was established to investigate the regional impact of climate and land use change. TERENO-NE focuses on the Northeast German lowlands, for which a high vulnerability has been determined due to increasing temperatures and decreasing amounts of precipitation projected for the coming decades. To facilitate in-depth evaluations of the effects of climate and land use changes and to separate the effects of natural and anthropogenic drivers in the region, six sites were chosen for comprehensive monitoring. In addition, at selected sites, geoarchives were used to substantially extend the instrumental records back in time. It is this combination of diverse disciplines working across different time scales that makes the observatory TERENO-NE a unique observation platform. We provide information about the general characteristics of the observatory and its six monitoring sites and present examples of interdisciplinary research activities at some of these sites. We also illustrate how monitoring improves process understanding, how remote sensing techniques are fine-tuned by the most comprehensive ground-truthing site DEMMIN, how soil erosion dynamics have evolved, how greenhouse gas monitoring of rewetted peatlands can reveal unexpected mechanisms, and how proxy data provides a long-term perspective of current ongoing changes.}, language = {en} }